xref: /netbsd/sys/external/bsd/ipf/netinet/ip_nat.c (revision c3377fcb)
1 /*	$NetBSD: ip_nat.c,v 1.26 2022/02/02 05:40:58 msaitoh Exp $	*/
2 
3 /*
4  * Copyright (C) 2012 by Darren Reed.
5  *
6  * See the IPFILTER.LICENCE file for details on licencing.
7  */
8 #if defined(KERNEL) || defined(_KERNEL)
9 # undef KERNEL
10 # undef KERNEL
11 # define        KERNEL	1
12 # define        KERNEL	1
13 #endif
14 #include <sys/errno.h>
15 #include <sys/types.h>
16 #include <sys/param.h>
17 #include <sys/time.h>
18 #include <sys/file.h>
19 #if defined(_KERNEL) && \
20     (defined(__NetBSD_Version) && (__NetBSD_Version >= 399002000))
21 # include <sys/kauth.h>
22 #endif
23 #if !defined(_KERNEL)
24 # include <stdio.h>
25 # include <string.h>
26 # include <stdlib.h>
27 # define KERNEL
28 # ifdef _OpenBSD__
29 struct file;
30 # endif
31 # include <sys/uio.h>
32 # undef KERNEL
33 #endif
34 #if defined(_KERNEL) && \
35     defined(__FreeBSD_version) && (__FreeBSD_version >= 220000)
36 # include <sys/filio.h>
37 # include <sys/fcntl.h>
38 #else
39 # include <sys/ioctl.h>
40 #endif
41 #if !defined(AIX)
42 # include <sys/fcntl.h>
43 #endif
44 #if !defined(linux)
45 # include <sys/protosw.h>
46 #endif
47 #include <sys/socket.h>
48 #if defined(_KERNEL)
49 # include <sys/systm.h>
50 # if !defined(__SVR4) && !defined(__svr4__)
51 #  include <sys/mbuf.h>
52 # endif
53 #endif
54 #if defined(__SVR4) || defined(__svr4__)
55 # include <sys/filio.h>
56 # include <sys/byteorder.h>
57 # ifdef KERNEL
58 #  include <sys/dditypes.h>
59 # endif
60 # include <sys/stream.h>
61 # include <sys/kmem.h>
62 #endif
63 #if _FreeBSD_version >= 300000
64 # include <sys/queue.h>
65 #endif
66 #include <net/if.h>
67 #if _FreeBSD_version >= 300000
68 # include <net/if_var.h>
69 #endif
70 #ifdef sun
71 # include <net/af.h>
72 #endif
73 #include <netinet/in.h>
74 #include <netinet/in_systm.h>
75 #include <netinet/ip.h>
76 
77 #ifdef RFC1825
78 # include <vpn/md5.h>
79 # include <vpn/ipsec.h>
80 extern struct ifnet vpnif;
81 #endif
82 
83 #if !defined(linux)
84 # include <netinet/ip_var.h>
85 #endif
86 #include <netinet/tcp.h>
87 #include <netinet/udp.h>
88 #include <netinet/ip_icmp.h>
89 #include "netinet/ip_compat.h"
90 #include "netinet/ipl.h"
91 #include "netinet/ip_fil.h"
92 #include "netinet/ip_nat.h"
93 #include "netinet/ip_frag.h"
94 #include "netinet/ip_state.h"
95 #include "netinet/ip_proxy.h"
96 #include "netinet/ip_lookup.h"
97 #include "netinet/ip_dstlist.h"
98 #include "netinet/ip_sync.h"
99 #if FREEBSD_GE_REV(300000)
100 # include <sys/malloc.h>
101 #endif
102 #ifdef HAS_SYS_MD5_H
103 # include <sys/md5.h>
104 #else
105 # include "md5.h"
106 #endif
107 /* END OF INCLUDES */
108 
109 #undef	SOCKADDR_IN
110 #define	SOCKADDR_IN	struct sockaddr_in
111 
112 #if !defined(lint)
113 #if defined(__NetBSD__)
114 #include <sys/cdefs.h>
115 __KERNEL_RCSID(0, "$NetBSD: ip_nat.c,v 1.26 2022/02/02 05:40:58 msaitoh Exp $");
116 #else
117 static const char sccsid[] = "@(#)ip_nat.c	1.11 6/5/96 (C) 1995 Darren Reed";
118 static const char rcsid[] = "@(#)Id: ip_nat.c,v 1.1.1.2 2012/07/22 13:45:27 darrenr Exp";
119 #endif
120 #endif
121 
122 
123 #define	NATFSUM(n,v,f)	((v) == 4 ? (n)->f.in4.s_addr : (n)->f.i6[0] + \
124 			 (n)->f.i6[1] + (n)->f.i6[2] + (n)->f.i6[3])
125 #define	NBUMP(x)	softn->(x)++
126 #define	NBUMPD(x, y)	do { \
127 				softn->x.y++; \
128 				DT(y); \
129 			} while (0)
130 #define	NBUMPSIDE(y,x)	softn->ipf_nat_stats.ns_side[y].x++
131 #define	NBUMPSIDED(y,x)	do { softn->ipf_nat_stats.ns_side[y].x++; \
132 			     DT(x); } while (0)
133 #define	NBUMPSIDEX(y,x,z) \
134 			do { softn->ipf_nat_stats.ns_side[y].x++; \
135 			     DT(z); } while (0)
136 #define	NBUMPSIDEDF(y,x)do { softn->ipf_nat_stats.ns_side[y].x++; \
137 			     DT1(x, fr_info_t *, fin); } while (0)
138 
139 frentry_t	ipfnatblock;
140 
141 static const ipftuneable_t ipf_nat_tuneables[] = {
142 	/* nat */
143 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_lock) },
144 		"nat_lock",	0,	1,
145 		stsizeof(ipf_nat_softc_t, ipf_nat_lock),
146 		IPFT_RDONLY,		NULL,	NULL },
147 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_table_sz) },
148 		"nat_table_size", 1,	0x7fffffff,
149 		stsizeof(ipf_nat_softc_t, ipf_nat_table_sz),
150 		0,			NULL,	ipf_nat_rehash },
151 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_table_max) },
152 		"nat_table_max", 1,	0x7fffffff,
153 		stsizeof(ipf_nat_softc_t, ipf_nat_table_max),
154 		0,			NULL,	NULL },
155 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_maprules_sz) },
156 		"nat_rules_size", 1,	0x7fffffff,
157 		stsizeof(ipf_nat_softc_t, ipf_nat_maprules_sz),
158 		0,			NULL,	ipf_nat_rehash_rules },
159 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_rdrrules_sz) },
160 		"rdr_rules_size", 1,	0x7fffffff,
161 		stsizeof(ipf_nat_softc_t, ipf_nat_rdrrules_sz),
162 		0,			NULL,	ipf_nat_rehash_rules },
163 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_hostmap_sz) },
164 		"hostmap_size",	1,	0x7fffffff,
165 		stsizeof(ipf_nat_softc_t, ipf_nat_hostmap_sz),
166 		0,			NULL,	ipf_nat_hostmap_rehash },
167 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_maxbucket) },
168 		"nat_maxbucket",1,	0x7fffffff,
169 		stsizeof(ipf_nat_softc_t, ipf_nat_maxbucket),
170 		0,			NULL,	NULL },
171 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_logging) },
172 		"nat_logging",	0,	1,
173 		stsizeof(ipf_nat_softc_t, ipf_nat_logging),
174 		0,			NULL,	NULL },
175 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_doflush) },
176 		"nat_doflush",	0,	1,
177 		stsizeof(ipf_nat_softc_t, ipf_nat_doflush),
178 		0,			NULL,	NULL },
179 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_table_wm_low) },
180 		"nat_table_wm_low",	1,	99,
181 		stsizeof(ipf_nat_softc_t, ipf_nat_table_wm_low),
182 		0,			NULL,	NULL },
183 	{ { (void *)offsetof(ipf_nat_softc_t, ipf_nat_table_wm_high) },
184 		"nat_table_wm_high",	2,	100,
185 		stsizeof(ipf_nat_softc_t, ipf_nat_table_wm_high),
186 		0,			NULL,	NULL },
187 	{ { 0 },
188 		NULL,			0,	0,
189 		0,
190 		0,			NULL,	NULL }
191 };
192 
193 /* ======================================================================== */
194 /* How the NAT is organised and works.                                      */
195 /*                                                                          */
196 /* Inside (interface y) NAT       Outside (interface x)                     */
197 /* -------------------- -+- -------------------------------------           */
198 /* Packet going          |   out, processsed by ipf_nat_checkout() for x    */
199 /* ------------>         |   ------------>                                  */
200 /* src=10.1.1.1          |   src=192.1.1.1                                  */
201 /*                       |                                                  */
202 /*                       |   in, processed by ipf_nat_checkin() for x       */
203 /* <------------         |   <------------                                  */
204 /* dst=10.1.1.1          |   dst=192.1.1.1                                  */
205 /* -------------------- -+- -------------------------------------           */
206 /* ipf_nat_checkout() - changes ip_src and if required, sport               */
207 /*             - creates a new mapping, if required.                        */
208 /* ipf_nat_checkin()  - changes ip_dst and if required, dport               */
209 /*                                                                          */
210 /* In the NAT table, internal source is recorded as "in" and externally     */
211 /* seen as "out".                                                           */
212 /* ======================================================================== */
213 
214 
215 #if SOLARIS && !defined(INSTANCES)
216 extern	int		pfil_delayed_copy;
217 #endif
218 
219 static	int	ipf_nat_flush_entry(ipf_main_softc_t *, void *);
220 static	int	ipf_nat_getent(ipf_main_softc_t *, void *, int);
221 static	int	ipf_nat_getsz(ipf_main_softc_t *, void *, int);
222 static	int	ipf_nat_putent(ipf_main_softc_t *, void *, int);
223 static	void	ipf_nat_addmap(ipf_nat_softc_t *, ipnat_t *);
224 static	void	ipf_nat_addrdr(ipf_nat_softc_t *, ipnat_t *);
225 static	int	ipf_nat_builddivertmp(ipf_nat_softc_t *, ipnat_t *);
226 static	int	ipf_nat_clearlist(ipf_main_softc_t *, ipf_nat_softc_t *);
227 static	int	ipf_nat_cmp_rules(ipnat_t *, ipnat_t *);
228 static	int	ipf_nat_decap(fr_info_t *, nat_t *);
229 static	void	ipf_nat_delrule(ipf_main_softc_t *, ipf_nat_softc_t *,
230 				     ipnat_t *, int);
231 static	int	ipf_nat_extraflush(ipf_main_softc_t *, ipf_nat_softc_t *, int);
232 static	int	ipf_nat_finalise(fr_info_t *, nat_t *);
233 static	int	ipf_nat_flushtable(ipf_main_softc_t *, ipf_nat_softc_t *);
234 static	int	ipf_nat_getnext(ipf_main_softc_t *, ipftoken_t *,
235 				ipfgeniter_t *, ipfobj_t *);
236 static	int	ipf_nat_gettable(ipf_main_softc_t *, ipf_nat_softc_t *, char *);
237 static	hostmap_t *ipf_nat_hostmap(ipf_nat_softc_t *, ipnat_t *,
238 				   struct in_addr, struct in_addr,
239 				   struct in_addr, u_32_t);
240 static	int	ipf_nat_icmpquerytype(int);
241 static	int	ipf_nat_iterator(ipf_main_softc_t *, ipftoken_t *,
242 				 ipfgeniter_t *, ipfobj_t *);
243 static	int	ipf_nat_match(fr_info_t *, ipnat_t *);
244 static	int	ipf_nat_matcharray(nat_t *, int *, u_long);
245 static	int	ipf_nat_matchflush(ipf_main_softc_t *, ipf_nat_softc_t *,
246 				   void *);
247 static	void	ipf_nat_mssclamp(tcphdr_t *, u_32_t, fr_info_t *, u_short *);
248 static	int	ipf_nat_newmap(fr_info_t *, nat_t *, natinfo_t *);
249 static	int	ipf_nat_newdivert(fr_info_t *, nat_t *, natinfo_t *);
250 static	int	ipf_nat_newrdr(fr_info_t *, nat_t *, natinfo_t *);
251 static	int	ipf_nat_newrewrite(fr_info_t *, nat_t *, natinfo_t *);
252 static	int	ipf_nat_nextaddr(fr_info_t *, nat_addr_t *, u_32_t *, u_32_t *);
253 static	int	ipf_nat_nextaddrinit(ipf_main_softc_t *, char *,
254 				     nat_addr_t *, int, void *);
255 static	int	ipf_nat_resolverule(ipf_main_softc_t *, ipnat_t *);
256 static	int	ipf_nat_ruleaddrinit(ipf_main_softc_t *,
257 				     ipf_nat_softc_t *, ipnat_t *);
258 static	void	ipf_nat_rule_fini(ipf_main_softc_t *, ipnat_t *);
259 static	int	ipf_nat_rule_init(ipf_main_softc_t *, ipf_nat_softc_t *,
260 				       ipnat_t *);
261 static	int	ipf_nat_siocaddnat(ipf_main_softc_t *, ipf_nat_softc_t *,
262 					ipnat_t *, int);
263 static	void	ipf_nat_siocdelnat(ipf_main_softc_t *, ipf_nat_softc_t *,
264 					ipnat_t *, int);
265 static	void	ipf_nat_tabmove(ipf_nat_softc_t *, nat_t *);
266 
267 /* ------------------------------------------------------------------------ */
268 /* Function:    ipf_nat_main_load                                           */
269 /* Returns:     int - 0 == success, -1 == failure                           */
270 /* Parameters:  Nil                                                         */
271 /*                                                                          */
272 /* The only global NAT structure that needs to be initialised is the filter */
273 /* rule that is used with blocking packets.                                 */
274 /* ------------------------------------------------------------------------ */
275 int
ipf_nat_main_load(void)276 ipf_nat_main_load(void)
277 {
278 	bzero((char *)&ipfnatblock, sizeof(ipfnatblock));
279 	ipfnatblock.fr_flags = FR_BLOCK|FR_QUICK;
280 	ipfnatblock.fr_ref = 1;
281 
282 	return 0;
283 }
284 
285 
286 /* ------------------------------------------------------------------------ */
287 /* Function:    ipf_nat_main_unload                                         */
288 /* Returns:     int - 0 == success, -1 == failure                           */
289 /* Parameters:  Nil                                                         */
290 /*                                                                          */
291 /* A null-op function that exists as a placeholder so that the flow in      */
292 /* other functions is obvious.                                              */
293 /* ------------------------------------------------------------------------ */
294 int
ipf_nat_main_unload(void)295 ipf_nat_main_unload(void)
296 {
297 	return 0;
298 }
299 
300 
301 /* ------------------------------------------------------------------------ */
302 /* Function:    ipf_nat_soft_create                                         */
303 /* Returns:     void * - NULL = failure, else pointer to NAT context        */
304 /* Parameters:  softc(I) - pointer to soft context main structure           */
305 /*                                                                          */
306 /* Allocate the initial soft context structure for NAT and populate it with */
307 /* some default values. Creating the tables is left until we call _init so  */
308 /* that sizes can be changed before we get under way.                       */
309 /* ------------------------------------------------------------------------ */
310 void *
ipf_nat_soft_create(ipf_main_softc_t * softc)311 ipf_nat_soft_create(ipf_main_softc_t *softc)
312 {
313 	ipf_nat_softc_t *softn;
314 
315 	KMALLOC(softn, ipf_nat_softc_t *);
316 	if (softn == NULL)
317 		return NULL;
318 
319 	bzero((char *)softn, sizeof(*softn));
320 
321 	softn->ipf_nat_tune = ipf_tune_array_copy(softn,
322 						  sizeof(ipf_nat_tuneables),
323 						  ipf_nat_tuneables);
324 	if (softn->ipf_nat_tune == NULL) {
325 		ipf_nat_soft_destroy(softc, softn);
326 		return NULL;
327 	}
328 	if (ipf_tune_array_link(softc, softn->ipf_nat_tune) == -1) {
329 		ipf_nat_soft_destroy(softc, softn);
330 		return NULL;
331 	}
332 
333 	softn->ipf_nat_list_tail = &softn->ipf_nat_list;
334 
335 	softn->ipf_nat_table_max = NAT_TABLE_MAX;
336 	softn->ipf_nat_table_sz = NAT_TABLE_SZ;
337 	softn->ipf_nat_maprules_sz = NAT_SIZE;
338 	softn->ipf_nat_rdrrules_sz = RDR_SIZE;
339 	softn->ipf_nat_hostmap_sz = HOSTMAP_SIZE;
340 	softn->ipf_nat_doflush = 0;
341 #ifdef  IPFILTER_LOG
342 	softn->ipf_nat_logging = 1;
343 #else
344 	softn->ipf_nat_logging = 0;
345 #endif
346 
347 	softn->ipf_nat_defage = DEF_NAT_AGE;
348 	softn->ipf_nat_defipage = IPF_TTLVAL(60);
349 	softn->ipf_nat_deficmpage = IPF_TTLVAL(3);
350 	softn->ipf_nat_table_wm_high = 99;
351 	softn->ipf_nat_table_wm_low = 90;
352 
353 	return softn;
354 }
355 
356 /* ------------------------------------------------------------------------ */
357 /* Function:    ipf_nat_soft_destroy                                        */
358 /* Returns:     Nil                                                         */
359 /* Parameters:  softc(I) - pointer to soft context main structure           */
360 /*                                                                          */
361 /* ------------------------------------------------------------------------ */
362 void
ipf_nat_soft_destroy(ipf_main_softc_t * softc,void * arg)363 ipf_nat_soft_destroy(ipf_main_softc_t *softc, void *arg)
364 {
365 	ipf_nat_softc_t *softn = arg;
366 
367 	if (softn->ipf_nat_tune != NULL) {
368 		ipf_tune_array_unlink(softc, softn->ipf_nat_tune);
369 		KFREES(softn->ipf_nat_tune, sizeof(ipf_nat_tuneables));
370 		softn->ipf_nat_tune = NULL;
371 	}
372 
373 	KFREE(softn);
374 }
375 
376 
377 /* ------------------------------------------------------------------------ */
378 /* Function:    ipf_nat_init                                                */
379 /* Returns:     int - 0 == success, -1 == failure                           */
380 /* Parameters:  softc(I) - pointer to soft context main structure           */
381 /*                                                                          */
382 /* Initialise all of the NAT locks, tables and other structures.            */
383 /* ------------------------------------------------------------------------ */
384 int
ipf_nat_soft_init(ipf_main_softc_t * softc,void * arg)385 ipf_nat_soft_init(ipf_main_softc_t *softc, void *arg)
386 {
387 	ipf_nat_softc_t *softn = arg;
388 	ipftq_t *tq;
389 	int i;
390 
391 	KMALLOCS(softn->ipf_nat_table[0], nat_t **, \
392 		 sizeof(nat_t *) * softn->ipf_nat_table_sz);
393 
394 	if (softn->ipf_nat_table[0] != NULL) {
395 		bzero((char *)softn->ipf_nat_table[0],
396 		      softn->ipf_nat_table_sz * sizeof(nat_t *));
397 	} else {
398 		return -1;
399 	}
400 
401 	KMALLOCS(softn->ipf_nat_table[1], nat_t **, \
402 		 sizeof(nat_t *) * softn->ipf_nat_table_sz);
403 
404 	if (softn->ipf_nat_table[1] != NULL) {
405 		bzero((char *)softn->ipf_nat_table[1],
406 		      softn->ipf_nat_table_sz * sizeof(nat_t *));
407 	} else {
408 		return -2;
409 	}
410 
411 	KMALLOCS(softn->ipf_nat_map_rules, ipnat_t **, \
412 		 sizeof(ipnat_t *) * softn->ipf_nat_maprules_sz);
413 
414 	if (softn->ipf_nat_map_rules != NULL) {
415 		bzero((char *)softn->ipf_nat_map_rules,
416 		      softn->ipf_nat_maprules_sz * sizeof(ipnat_t *));
417 	} else {
418 		return -3;
419 	}
420 
421 	KMALLOCS(softn->ipf_nat_rdr_rules, ipnat_t **, \
422 		 sizeof(ipnat_t *) * softn->ipf_nat_rdrrules_sz);
423 
424 	if (softn->ipf_nat_rdr_rules != NULL) {
425 		bzero((char *)softn->ipf_nat_rdr_rules,
426 		      softn->ipf_nat_rdrrules_sz * sizeof(ipnat_t *));
427 	} else {
428 		return -4;
429 	}
430 
431 	KMALLOCS(softn->ipf_hm_maptable, hostmap_t **, \
432 		 sizeof(hostmap_t *) * softn->ipf_nat_hostmap_sz);
433 
434 	if (softn->ipf_hm_maptable != NULL) {
435 		bzero((char *)softn->ipf_hm_maptable,
436 		      sizeof(hostmap_t *) * softn->ipf_nat_hostmap_sz);
437 	} else {
438 		return -5;
439 	}
440 	softn->ipf_hm_maplist = NULL;
441 
442 	KMALLOCS(softn->ipf_nat_stats.ns_side[0].ns_bucketlen, u_int *,
443 		 softn->ipf_nat_table_sz * sizeof(u_int));
444 
445 	if (softn->ipf_nat_stats.ns_side[0].ns_bucketlen == NULL) {
446 		return -6;
447 	}
448 	bzero((char *)softn->ipf_nat_stats.ns_side[0].ns_bucketlen,
449 	      softn->ipf_nat_table_sz * sizeof(u_int));
450 
451 	KMALLOCS(softn->ipf_nat_stats.ns_side[1].ns_bucketlen, u_int *,
452 		 softn->ipf_nat_table_sz * sizeof(u_int));
453 
454 	if (softn->ipf_nat_stats.ns_side[1].ns_bucketlen == NULL) {
455 		return -7;
456 	}
457 
458 	bzero((char *)softn->ipf_nat_stats.ns_side[1].ns_bucketlen,
459 	      softn->ipf_nat_table_sz * sizeof(u_int));
460 
461 	if (softn->ipf_nat_maxbucket == 0) {
462 		for (i = softn->ipf_nat_table_sz; i > 0; i >>= 1)
463 			softn->ipf_nat_maxbucket++;
464 		softn->ipf_nat_maxbucket *= 2;
465 	}
466 
467 	ipf_sttab_init(softc, softn->ipf_nat_tcptq);
468 	/*
469 	 * Increase this because we may have "keep state" following this too
470 	 * and packet storms can occur if this is removed too quickly.
471 	 */
472 	softn->ipf_nat_tcptq[IPF_TCPS_CLOSED].ifq_ttl = softc->ipf_tcplastack;
473 	softn->ipf_nat_tcptq[IPF_TCP_NSTATES - 1].ifq_next =
474 							&softn->ipf_nat_udptq;
475 
476 	IPFTQ_INIT(&softn->ipf_nat_udptq, softn->ipf_nat_defage,
477 		   "nat ipftq udp tab");
478 	softn->ipf_nat_udptq.ifq_next = &softn->ipf_nat_udpacktq;
479 
480 	IPFTQ_INIT(&softn->ipf_nat_udpacktq, softn->ipf_nat_defage,
481 		   "nat ipftq udpack tab");
482 	softn->ipf_nat_udpacktq.ifq_next = &softn->ipf_nat_icmptq;
483 
484 	IPFTQ_INIT(&softn->ipf_nat_icmptq, softn->ipf_nat_deficmpage,
485 		   "nat icmp ipftq tab");
486 	softn->ipf_nat_icmptq.ifq_next = &softn->ipf_nat_icmpacktq;
487 
488 	IPFTQ_INIT(&softn->ipf_nat_icmpacktq, softn->ipf_nat_defage,
489 		   "nat icmpack ipftq tab");
490 	softn->ipf_nat_icmpacktq.ifq_next = &softn->ipf_nat_iptq;
491 
492 	IPFTQ_INIT(&softn->ipf_nat_iptq, softn->ipf_nat_defipage,
493 		   "nat ip ipftq tab");
494 	softn->ipf_nat_iptq.ifq_next = &softn->ipf_nat_pending;
495 
496 	IPFTQ_INIT(&softn->ipf_nat_pending, 1, "nat pending ipftq tab");
497 	softn->ipf_nat_pending.ifq_next = NULL;
498 
499 	for (i = 0, tq = softn->ipf_nat_tcptq; i < IPF_TCP_NSTATES; i++, tq++) {
500 		if (tq->ifq_ttl < softn->ipf_nat_deficmpage)
501 			tq->ifq_ttl = softn->ipf_nat_deficmpage;
502 #ifdef LARGE_NAT
503 		else if (tq->ifq_ttl > softn->ipf_nat_defage)
504 			tq->ifq_ttl = softn->ipf_nat_defage;
505 #endif
506 	}
507 
508 	/*
509 	 * Increase this because we may have "keep state" following
510 	 * this too and packet storms can occur if this is removed
511 	 * too quickly.
512 	 */
513 	softn->ipf_nat_tcptq[IPF_TCPS_CLOSED].ifq_ttl = softc->ipf_tcplastack;
514 
515 	MUTEX_INIT(&softn->ipf_nat_new, "ipf nat new mutex");
516 	MUTEX_INIT(&softn->ipf_nat_io, "ipf nat io mutex");
517 
518 	softn->ipf_nat_inited = 1;
519 
520 	return 0;
521 }
522 
523 
524 /* ------------------------------------------------------------------------ */
525 /* Function:    ipf_nat_soft_fini                                           */
526 /* Returns:     Nil                                                         */
527 /* Parameters:  softc(I) - pointer to soft context main structure           */
528 /*                                                                          */
529 /* Free all memory used by NAT structures allocated at runtime.             */
530 /* ------------------------------------------------------------------------ */
531 int
ipf_nat_soft_fini(ipf_main_softc_t * softc,void * arg)532 ipf_nat_soft_fini(ipf_main_softc_t *softc, void *arg)
533 {
534 	ipf_nat_softc_t *softn = arg;
535 	ipftq_t *ifq, *ifqnext;
536 
537 	(void) ipf_nat_clearlist(softc, softn);
538 	(void) ipf_nat_flushtable(softc, softn);
539 
540 	/*
541 	 * Proxy timeout queues are not cleaned here because although they
542 	 * exist on the NAT list, ipf_proxy_unload is called after unload
543 	 * and the proxies actually are responsible for them being created.
544 	 * Should the proxy timeouts have their own list?  There's no real
545 	 * justification as this is the only complication.
546 	 */
547 	for (ifq = softn->ipf_nat_utqe; ifq != NULL; ifq = ifqnext) {
548 		ifqnext = ifq->ifq_next;
549 		if (ipf_deletetimeoutqueue(ifq) == 0)
550 			ipf_freetimeoutqueue(softc, ifq);
551 	}
552 
553 	if (softn->ipf_nat_table[0] != NULL) {
554 		KFREES(softn->ipf_nat_table[0],
555 		       sizeof(nat_t *) * softn->ipf_nat_table_sz);
556 		softn->ipf_nat_table[0] = NULL;
557 	}
558 	if (softn->ipf_nat_table[1] != NULL) {
559 		KFREES(softn->ipf_nat_table[1],
560 		       sizeof(nat_t *) * softn->ipf_nat_table_sz);
561 		softn->ipf_nat_table[1] = NULL;
562 	}
563 	if (softn->ipf_nat_map_rules != NULL) {
564 		KFREES(softn->ipf_nat_map_rules,
565 		       sizeof(ipnat_t *) * softn->ipf_nat_maprules_sz);
566 		softn->ipf_nat_map_rules = NULL;
567 	}
568 	if (softn->ipf_nat_rdr_rules != NULL) {
569 		KFREES(softn->ipf_nat_rdr_rules,
570 		       sizeof(ipnat_t *) * softn->ipf_nat_rdrrules_sz);
571 		softn->ipf_nat_rdr_rules = NULL;
572 	}
573 	if (softn->ipf_hm_maptable != NULL) {
574 		KFREES(softn->ipf_hm_maptable,
575 		       sizeof(hostmap_t *) * softn->ipf_nat_hostmap_sz);
576 		softn->ipf_hm_maptable = NULL;
577 	}
578 	if (softn->ipf_nat_stats.ns_side[0].ns_bucketlen != NULL) {
579 		KFREES(softn->ipf_nat_stats.ns_side[0].ns_bucketlen,
580 		       sizeof(u_int) * softn->ipf_nat_table_sz);
581 		softn->ipf_nat_stats.ns_side[0].ns_bucketlen = NULL;
582 	}
583 	if (softn->ipf_nat_stats.ns_side[1].ns_bucketlen != NULL) {
584 		KFREES(softn->ipf_nat_stats.ns_side[1].ns_bucketlen,
585 		       sizeof(u_int) * softn->ipf_nat_table_sz);
586 		softn->ipf_nat_stats.ns_side[1].ns_bucketlen = NULL;
587 	}
588 
589 	if (softn->ipf_nat_inited == 1) {
590 		softn->ipf_nat_inited = 0;
591 		ipf_sttab_destroy(softn->ipf_nat_tcptq);
592 
593 		MUTEX_DESTROY(&softn->ipf_nat_new);
594 		MUTEX_DESTROY(&softn->ipf_nat_io);
595 
596 		MUTEX_DESTROY(&softn->ipf_nat_udptq.ifq_lock);
597 		MUTEX_DESTROY(&softn->ipf_nat_udpacktq.ifq_lock);
598 		MUTEX_DESTROY(&softn->ipf_nat_icmptq.ifq_lock);
599 		MUTEX_DESTROY(&softn->ipf_nat_icmpacktq.ifq_lock);
600 		MUTEX_DESTROY(&softn->ipf_nat_iptq.ifq_lock);
601 		MUTEX_DESTROY(&softn->ipf_nat_pending.ifq_lock);
602 	}
603 
604 	return 0;
605 }
606 
607 
608 /* ------------------------------------------------------------------------ */
609 /* Function:    ipf_nat_setlock                                             */
610 /* Returns:     Nil                                                         */
611 /* Parameters:  arg(I) - pointer to soft state information                  */
612 /*              tmp(I) - new lock value                                     */
613 /*                                                                          */
614 /* Set the "lock status" of NAT to the value in tmp.                        */
615 /* ------------------------------------------------------------------------ */
616 void
ipf_nat_setlock(void * arg,int tmp)617 ipf_nat_setlock(void *arg, int tmp)
618 {
619 	ipf_nat_softc_t *softn = arg;
620 
621 	softn->ipf_nat_lock = tmp;
622 }
623 
624 
625 /* ------------------------------------------------------------------------ */
626 /* Function:    ipf_nat_addrdr                                              */
627 /* Returns:     Nil                                                         */
628 /* Parameters:  n(I) - pointer to NAT rule to add                           */
629 /*                                                                          */
630 /* Adds a redirect rule to the hash table of redirect rules and the list of */
631 /* loaded NAT rules.  Updates the bitmask indicating which netmasks are in  */
632 /* use by redirect rules.                                                   */
633 /* ------------------------------------------------------------------------ */
634 static void
ipf_nat_addrdr(ipf_nat_softc_t * softn,ipnat_t * n)635 ipf_nat_addrdr(ipf_nat_softc_t *softn, ipnat_t *n)
636 {
637 	ipnat_t **np;
638 	u_32_t j;
639 	u_int hv;
640 	u_int rhv;
641 	int k;
642 
643 	if (n->in_odstatype == FRI_NORMAL) {
644 		k = count4bits(n->in_odstmsk);
645 		ipf_inet_mask_add(k, &softn->ipf_nat_rdr_mask);
646 		j = (n->in_odstaddr & n->in_odstmsk);
647 		rhv = NAT_HASH_FN(j, 0, 0xffffffff);
648 	} else {
649 		ipf_inet_mask_add(0, &softn->ipf_nat_rdr_mask);
650 		j = 0;
651 		rhv = 0;
652 	}
653 	hv = rhv % softn->ipf_nat_rdrrules_sz;
654 	np = softn->ipf_nat_rdr_rules + hv;
655 	while (*np != NULL)
656 		np = &(*np)->in_rnext;
657 	n->in_rnext = NULL;
658 	n->in_prnext = np;
659 	n->in_hv[0] = hv;
660 	n->in_use++;
661 	*np = n;
662 }
663 
664 
665 /* ------------------------------------------------------------------------ */
666 /* Function:    ipf_nat_addmap                                              */
667 /* Returns:     Nil                                                         */
668 /* Parameters:  n(I) - pointer to NAT rule to add                           */
669 /*                                                                          */
670 /* Adds a NAT map rule to the hash table of rules and the list of  loaded   */
671 /* NAT rules.  Updates the bitmask indicating which netmasks are in use by  */
672 /* redirect rules.                                                          */
673 /* ------------------------------------------------------------------------ */
674 static void
ipf_nat_addmap(ipf_nat_softc_t * softn,ipnat_t * n)675 ipf_nat_addmap(ipf_nat_softc_t *softn, ipnat_t *n)
676 {
677 	ipnat_t **np;
678 	u_32_t j;
679 	u_int hv;
680 	u_int rhv;
681 	int k;
682 
683 	if (n->in_osrcatype == FRI_NORMAL) {
684 		k = count4bits(n->in_osrcmsk);
685 		ipf_inet_mask_add(k, &softn->ipf_nat_map_mask);
686 		j = (n->in_osrcaddr & n->in_osrcmsk);
687 		rhv = NAT_HASH_FN(j, 0, 0xffffffff);
688 	} else {
689 		ipf_inet_mask_add(0, &softn->ipf_nat_map_mask);
690 		j = 0;
691 		rhv = 0;
692 	}
693 	hv = rhv % softn->ipf_nat_maprules_sz;
694 	np = softn->ipf_nat_map_rules + hv;
695 	while (*np != NULL)
696 		np = &(*np)->in_mnext;
697 	n->in_mnext = NULL;
698 	n->in_pmnext = np;
699 	n->in_hv[1] = rhv;
700 	n->in_use++;
701 	*np = n;
702 }
703 
704 
705 /* ------------------------------------------------------------------------ */
706 /* Function:    ipf_nat_delrdr                                              */
707 /* Returns:     Nil                                                         */
708 /* Parameters:  n(I) - pointer to NAT rule to delete                        */
709 /*                                                                          */
710 /* Removes a redirect rule from the hash table of redirect rules.           */
711 /* ------------------------------------------------------------------------ */
712 void
ipf_nat_delrdr(ipf_nat_softc_t * softn,ipnat_t * n)713 ipf_nat_delrdr(ipf_nat_softc_t *softn, ipnat_t *n)
714 {
715 	if (n->in_odstatype == FRI_NORMAL) {
716 		int k = count4bits(n->in_odstmsk);
717 		ipf_inet_mask_del(k, &softn->ipf_nat_rdr_mask);
718 	} else {
719 		ipf_inet_mask_del(0, &softn->ipf_nat_rdr_mask);
720 	}
721 	if (n->in_rnext)
722 		n->in_rnext->in_prnext = n->in_prnext;
723 	*n->in_prnext = n->in_rnext;
724 	n->in_use--;
725 }
726 
727 
728 /* ------------------------------------------------------------------------ */
729 /* Function:    ipf_nat_delmap                                              */
730 /* Returns:     Nil                                                         */
731 /* Parameters:  n(I) - pointer to NAT rule to delete                        */
732 /*                                                                          */
733 /* Removes a NAT map rule from the hash table of NAT map rules.             */
734 /* ------------------------------------------------------------------------ */
735 void
ipf_nat_delmap(ipf_nat_softc_t * softn,ipnat_t * n)736 ipf_nat_delmap(ipf_nat_softc_t *softn, ipnat_t *n)
737 {
738 	if (n->in_osrcatype == FRI_NORMAL) {
739 		int k = count4bits(n->in_osrcmsk);
740 		ipf_inet_mask_del(k, &softn->ipf_nat_map_mask);
741 	} else {
742 		ipf_inet_mask_del(0, &softn->ipf_nat_map_mask);
743 	}
744 	if (n->in_mnext != NULL)
745 		n->in_mnext->in_pmnext = n->in_pmnext;
746 	*n->in_pmnext = n->in_mnext;
747 	n->in_use--;
748 }
749 
750 
751 /* ------------------------------------------------------------------------ */
752 /* Function:    ipf_nat_hostmap                                             */
753 /* Returns:     struct hostmap* - NULL if no hostmap could be created,      */
754 /*                                else a pointer to the hostmapping to use  */
755 /* Parameters:  np(I)   - pointer to NAT rule                               */
756 /*              real(I) - real IP address                                   */
757 /*              map(I)  - mapped IP address                                 */
758 /*              port(I) - destination port number                           */
759 /* Write Locks: ipf_nat                                                     */
760 /*                                                                          */
761 /* Check if an ip address has already been allocated for a given mapping    */
762 /* that is not doing port based translation.  If is not yet allocated, then */
763 /* create a new entry if a non-NULL NAT rule pointer has been supplied.     */
764 /* ------------------------------------------------------------------------ */
765 static struct hostmap *
ipf_nat_hostmap(ipf_nat_softc_t * softn,ipnat_t * np,struct in_addr src,struct in_addr dst,struct in_addr map,u_32_t port)766 ipf_nat_hostmap(ipf_nat_softc_t *softn, ipnat_t *np, struct in_addr src,
767     struct in_addr dst, struct in_addr map, u_32_t port)
768 {
769 	hostmap_t *hm;
770 	u_int hv, rhv;
771 
772 	hv = (src.s_addr ^ dst.s_addr);
773 	hv += src.s_addr;
774 	hv += dst.s_addr;
775 	rhv = hv;
776 	hv %= softn->ipf_nat_hostmap_sz;
777 	for (hm = softn->ipf_hm_maptable[hv]; hm; hm = hm->hm_hnext)
778 		if ((hm->hm_osrcip.s_addr == src.s_addr) &&
779 		    (hm->hm_odstip.s_addr == dst.s_addr) &&
780 		    ((np == NULL) || (np == hm->hm_ipnat)) &&
781 		    ((port == 0) || (port == hm->hm_port))) {
782 			softn->ipf_nat_stats.ns_hm_addref++;
783 			hm->hm_ref++;
784 			return hm;
785 		}
786 
787 	if (np == NULL) {
788 		softn->ipf_nat_stats.ns_hm_nullnp++;
789 		return NULL;
790 	}
791 
792 	KMALLOC(hm, hostmap_t *);
793 	if (hm) {
794 		hm->hm_next = softn->ipf_hm_maplist;
795 		hm->hm_pnext = &softn->ipf_hm_maplist;
796 		if (softn->ipf_hm_maplist != NULL)
797 			softn->ipf_hm_maplist->hm_pnext = &hm->hm_next;
798 		softn->ipf_hm_maplist = hm;
799 		hm->hm_hnext = softn->ipf_hm_maptable[hv];
800 		hm->hm_phnext = softn->ipf_hm_maptable + hv;
801 		if (softn->ipf_hm_maptable[hv] != NULL)
802 			softn->ipf_hm_maptable[hv]->hm_phnext = &hm->hm_hnext;
803 		softn->ipf_hm_maptable[hv] = hm;
804 		hm->hm_ipnat = np;
805 		np->in_use++;
806 		hm->hm_osrcip = src;
807 		hm->hm_odstip = dst;
808 		hm->hm_nsrcip = map;
809 		hm->hm_ndstip.s_addr = 0;
810 		hm->hm_ref = 1;
811 		hm->hm_port = port;
812 		hm->hm_hv = rhv;
813 		hm->hm_v = 4;
814 		softn->ipf_nat_stats.ns_hm_new++;
815 	} else {
816 		softn->ipf_nat_stats.ns_hm_newfail++;
817 	}
818 	return hm;
819 }
820 
821 
822 /* ------------------------------------------------------------------------ */
823 /* Function:    ipf_nat_hostmapdel                                          */
824 /* Returns:     Nil                                                         */
825 /* Parameters:  hmp(I) - pointer to hostmap structure pointer               */
826 /* Write Locks: ipf_nat                                                     */
827 /*                                                                          */
828 /* Decrement the references to this hostmap structure by one.  If this      */
829 /* reaches zero then remove it and free it.                                 */
830 /* ------------------------------------------------------------------------ */
831 void
ipf_nat_hostmapdel(ipf_main_softc_t * softc,struct hostmap ** hmp)832 ipf_nat_hostmapdel(ipf_main_softc_t *softc, struct hostmap **hmp)
833 {
834 	struct hostmap *hm;
835 
836 	hm = *hmp;
837 	*hmp = NULL;
838 
839 	hm->hm_ref--;
840 	if (hm->hm_ref == 0) {
841 		ipf_nat_rule_deref(softc, &hm->hm_ipnat);
842 		if (hm->hm_hnext)
843 			hm->hm_hnext->hm_phnext = hm->hm_phnext;
844 		*hm->hm_phnext = hm->hm_hnext;
845 		if (hm->hm_next)
846 			hm->hm_next->hm_pnext = hm->hm_pnext;
847 		*hm->hm_pnext = hm->hm_next;
848 		KFREE(hm);
849 	}
850 }
851 
852 
853 /* ------------------------------------------------------------------------ */
854 /* Function:    ipf_fix_outcksum                                            */
855 /* Returns:     Nil                                                         */
856 /* Parameters:  fin(I) - pointer to packet information                      */
857 /*              sp(I)  - location of 16bit checksum to update               */
858 /*              n((I)  - amount to adjust checksum by                       */
859 /*                                                                          */
860 /* Adjusts the 16bit checksum by "n" for packets going out.                 */
861 /* ------------------------------------------------------------------------ */
862 void
ipf_fix_outcksum(int cksum,u_short * sp,u_32_t n,u_32_t partial)863 ipf_fix_outcksum(int cksum, u_short *sp, u_32_t n, u_32_t partial)
864 {
865 	u_short sumshort;
866 	u_32_t sum1;
867 
868 	if (n == 0)
869 		return;
870 
871 	if (cksum == 4) {
872 		*sp = 0;
873 		return;
874 	}
875 	if (cksum == 2) {
876 		sum1 = partial;
877 		sum1 = (sum1 & 0xffff) + (sum1 >> 16);
878 		*sp = htons(sum1);
879 		return;
880 	}
881 	sum1 = (~ntohs(*sp)) & 0xffff;
882 	sum1 += (n);
883 	sum1 = (sum1 >> 16) + (sum1 & 0xffff);
884 	/* Again */
885 	sum1 = (sum1 >> 16) + (sum1 & 0xffff);
886 	sumshort = ~(u_short)sum1;
887 	*(sp) = htons(sumshort);
888 }
889 
890 
891 /* ------------------------------------------------------------------------ */
892 /* Function:    ipf_fix_incksum                                             */
893 /* Returns:     Nil                                                         */
894 /* Parameters:  fin(I) - pointer to packet information                      */
895 /*              sp(I)  - location of 16bit checksum to update               */
896 /*              n((I)  - amount to adjust checksum by                       */
897 /*                                                                          */
898 /* Adjusts the 16bit checksum by "n" for packets going in.                  */
899 /* ------------------------------------------------------------------------ */
900 void
ipf_fix_incksum(int cksum,u_short * sp,u_32_t n,u_32_t partial)901 ipf_fix_incksum(int cksum, u_short *sp, u_32_t n, u_32_t partial)
902 {
903 	u_short sumshort;
904 	u_32_t sum1;
905 
906 	if (n == 0)
907 		return;
908 
909 	if (cksum == 4) {
910 		*sp = 0;
911 		return;
912 	}
913 	if (cksum == 2) {
914 		sum1 = partial;
915 		sum1 = (sum1 & 0xffff) + (sum1 >> 16);
916 		*sp = htons(sum1);
917 		return;
918 	}
919 
920 	sum1 = (~ntohs(*sp)) & 0xffff;
921 	sum1 += ~(n) & 0xffff;
922 	sum1 = (sum1 >> 16) + (sum1 & 0xffff);
923 	/* Again */
924 	sum1 = (sum1 >> 16) + (sum1 & 0xffff);
925 	sumshort = ~(u_short)sum1;
926 	*(sp) = htons(sumshort);
927 }
928 
929 
930 /* ------------------------------------------------------------------------ */
931 /* Function:    ipf_fix_datacksum                                           */
932 /* Returns:     Nil                                                         */
933 /* Parameters:  sp(I)  - location of 16bit checksum to update               */
934 /*              n((I)  - amount to adjust checksum by                       */
935 /*                                                                          */
936 /* Fix_datacksum is used *only* for the adjustments of checksums in the     */
937 /* data section of an IP packet.                                            */
938 /*                                                                          */
939 /* The only situation in which you need to do this is when NAT'ing an       */
940 /* ICMP error message. Such a message, contains in its body the IP header   */
941 /* of the original IP packet, that causes the error.                        */
942 /*                                                                          */
943 /* You can't use fix_incksum or fix_outcksum in that case, because for the  */
944 /* kernel the data section of the ICMP error is just data, and no special   */
945 /* processing like hardware cksum or ntohs processing have been done by the */
946 /* kernel on the data section.                                              */
947 /* ------------------------------------------------------------------------ */
948 void
ipf_fix_datacksum(u_short * sp,u_32_t n)949 ipf_fix_datacksum(u_short *sp, u_32_t n)
950 {
951 	u_short sumshort;
952 	u_32_t sum1;
953 
954 	if (n == 0)
955 		return;
956 
957 	sum1 = (~ntohs(*sp)) & 0xffff;
958 	sum1 += (n);
959 	sum1 = (sum1 >> 16) + (sum1 & 0xffff);
960 	/* Again */
961 	sum1 = (sum1 >> 16) + (sum1 & 0xffff);
962 	sumshort = ~(u_short)sum1;
963 	*(sp) = htons(sumshort);
964 }
965 
966 
967 /* ------------------------------------------------------------------------ */
968 /* Function:    ipf_nat_ioctl                                               */
969 /* Returns:     int - 0 == success, != 0 == failure                         */
970 /* Parameters:  softc(I) - pointer to soft context main structure           */
971 /*              data(I)  - pointer to ioctl data                            */
972 /*              cmd(I)   - ioctl command integer                            */
973 /*              mode(I)  - file mode bits used with open                    */
974 /*              uid(I)   - uid of calling process                           */
975 /*              ctx(I)   - pointer used as key for finding context          */
976 /*                                                                          */
977 /* Processes an ioctl call made to operate on the IP Filter NAT device.     */
978 /* ------------------------------------------------------------------------ */
979 int
ipf_nat_ioctl(ipf_main_softc_t * softc,void * data,ioctlcmd_t cmd,int mode,int uid,void * ctx)980 ipf_nat_ioctl(ipf_main_softc_t *softc, void *data, ioctlcmd_t cmd, int mode,
981    int uid, void *ctx)
982 {
983 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
984 	int error = 0, ret, arg, getlock;
985 	ipnat_t *nat, *nt, *n;
986 	ipnat_t *natd = NULL;
987 	SPL_INT(s);
988 
989 #if BSD_GE_YEAR(199306) && defined(_KERNEL)
990 # if NETBSD_GE_REV(399002000)
991 	if ((mode & FWRITE) && kauth_authorize_network(
992 	    kauth_cred_get(), KAUTH_NETWORK_FIREWALL,
993 	    KAUTH_REQ_NETWORK_FIREWALL_FW, NULL, NULL, NULL))
994 # else
995 #  if defined(__FreeBSD_version) && (__FreeBSD_version >= 500034)
996 	if (securelevel_ge(curthread->td_ucred, 3) && (mode & FWRITE))
997 #  else
998 	if ((securelevel >= 3) && (mode & FWRITE))
999 #  endif
1000 # endif
1001 	{
1002 		IPFERROR(60001);
1003 		return EPERM;
1004 	}
1005 #endif
1006 
1007 #if defined(__osf__) && defined(_KERNEL)
1008 	getlock = 0;
1009 #else
1010 	getlock = (mode & NAT_LOCKHELD) ? 0 : 1;
1011 #endif
1012 
1013 	n = NULL;
1014 	nt = NULL;
1015 	nat = NULL;
1016 
1017 	if ((cmd == (ioctlcmd_t)SIOCADNAT) || (cmd == (ioctlcmd_t)SIOCRMNAT) ||
1018 	    (cmd == (ioctlcmd_t)SIOCPURGENAT)) {
1019 		KMALLOC(natd, ipnat_t *);
1020 		if (natd == NULL) {
1021 			error = ENOMEM;
1022 			goto done;
1023 		}
1024 		if (mode & NAT_SYSSPACE) {
1025 			bcopy(data, natd, sizeof(*natd));
1026 			nat = natd;
1027 			error = 0;
1028 		} else {
1029 			bzero(natd, sizeof(*natd));
1030 			error = ipf_inobj(softc, data, NULL, natd,
1031 					  IPFOBJ_IPNAT);
1032 			if (error != 0)
1033 				goto done;
1034 
1035 			if (natd->in_size < sizeof(ipnat_t)) {
1036 				error = EINVAL;
1037 				goto done;
1038 			}
1039 			KMALLOCS(nt, ipnat_t *, natd->in_size);
1040 			if (nt == NULL) {
1041 				IPFERROR(60070);
1042 				error = ENOMEM;
1043 				goto done;
1044 			}
1045 			bzero(nt, natd->in_size);
1046 			error = ipf_inobjsz(softc, data, nt, IPFOBJ_IPNAT,
1047 					    natd->in_size);
1048 			if (error)
1049 				goto done;
1050 			nat = nt;
1051 		}
1052 
1053 		/*
1054 		 * For add/delete, look to see if the NAT entry is
1055 		 * already present
1056 		 */
1057 		nat->in_flags &= IPN_USERFLAGS;
1058 		if ((nat->in_redir & NAT_MAPBLK) == 0) {
1059 			if (nat->in_osrcatype == FRI_NORMAL ||
1060 			    nat->in_osrcatype == FRI_NONE)
1061 				nat->in_osrcaddr &= nat->in_osrcmsk;
1062 			if (nat->in_odstatype == FRI_NORMAL ||
1063 			    nat->in_odstatype == FRI_NONE)
1064 				nat->in_odstaddr &= nat->in_odstmsk;
1065 			if ((nat->in_flags & (IPN_SPLIT|IPN_SIPRANGE)) == 0) {
1066 				if (nat->in_nsrcatype == FRI_NORMAL)
1067 					nat->in_nsrcaddr &= nat->in_nsrcmsk;
1068 				if (nat->in_ndstatype == FRI_NORMAL)
1069 					nat->in_ndstaddr &= nat->in_ndstmsk;
1070 			}
1071 		}
1072 
1073 		error = ipf_nat_rule_init(softc, softn, nat);
1074 		if (error != 0)
1075 			goto done;
1076 
1077 		MUTEX_ENTER(&softn->ipf_nat_io);
1078 		for (n = softn->ipf_nat_list; n != NULL; n = n->in_next)
1079 			if (ipf_nat_cmp_rules(nat, n) == 0)
1080 				break;
1081 	}
1082 
1083 	switch (cmd)
1084 	{
1085 #ifdef  IPFILTER_LOG
1086 	case SIOCIPFFB :
1087 	{
1088 		int tmp;
1089 
1090 		if (!(mode & FWRITE)) {
1091 			IPFERROR(60002);
1092 			error = EPERM;
1093 		} else {
1094 			tmp = ipf_log_clear(softc, IPL_LOGNAT);
1095 			error = BCOPYOUT(&tmp, data, sizeof(tmp));
1096 			if (error != 0) {
1097 				IPFERROR(60057);
1098 				error = EFAULT;
1099 			}
1100 		}
1101 		break;
1102 	}
1103 
1104 	case SIOCSETLG :
1105 		if (!(mode & FWRITE)) {
1106 			IPFERROR(60003);
1107 			error = EPERM;
1108 		} else {
1109 			error = BCOPYIN(data, &softn->ipf_nat_logging,
1110 					sizeof(softn->ipf_nat_logging));
1111 			if (error != 0)
1112 				error = EFAULT;
1113 		}
1114 		break;
1115 
1116 	case SIOCGETLG :
1117 		error = BCOPYOUT(&softn->ipf_nat_logging, data,
1118 				 sizeof(softn->ipf_nat_logging));
1119 		if (error != 0) {
1120 			IPFERROR(60004);
1121 			error = EFAULT;
1122 		}
1123 		break;
1124 
1125 	case FIONREAD :
1126 		arg = ipf_log_bytesused(softc, IPL_LOGNAT);
1127 		error = BCOPYOUT(&arg, data, sizeof(arg));
1128 		if (error != 0) {
1129 			IPFERROR(60005);
1130 			error = EFAULT;
1131 		}
1132 		break;
1133 #endif
1134 	case SIOCADNAT :
1135 		if (!(mode & FWRITE)) {
1136 			IPFERROR(60006);
1137 			error = EPERM;
1138 		} else if (n != NULL) {
1139 			KMALLOC(natd, ipnat_t *);
1140 			if (natd == NULL) {
1141 				error = ENOMEM;
1142 				goto done;
1143 			}
1144 			bzero(natd, sizeof(*natd));
1145 			natd->in_flineno = n->in_flineno;
1146 			(void) ipf_outobj(softc, data, &natd, IPFOBJ_IPNAT);
1147 			IPFERROR(60007);
1148 			error = EEXIST;
1149 		} else if (nt == NULL) {
1150 			IPFERROR(60008);
1151 			error = ENOMEM;
1152 		}
1153 		if (error != 0) {
1154 			MUTEX_EXIT(&softn->ipf_nat_io);
1155 			break;
1156 		}
1157 		if (nat != nt)
1158 			bcopy((char *)nat, (char *)nt, sizeof(*n));
1159 		error = ipf_nat_siocaddnat(softc, softn, nt, getlock);
1160 		MUTEX_EXIT(&softn->ipf_nat_io);
1161 		if (error == 0) {
1162 			nat = NULL;
1163 			nt = NULL;
1164 		}
1165 		break;
1166 
1167 	case SIOCRMNAT :
1168 	case SIOCPURGENAT :
1169 		if (!(mode & FWRITE)) {
1170 			IPFERROR(60009);
1171 			error = EPERM;
1172 			n = NULL;
1173 		} else if (n == NULL) {
1174 			IPFERROR(60010);
1175 			error = ESRCH;
1176 		}
1177 
1178 		if (error != 0) {
1179 			MUTEX_EXIT(&softn->ipf_nat_io);
1180 			break;
1181 		}
1182 		if (cmd == (ioctlcmd_t)SIOCPURGENAT) {
1183 			error = ipf_outobjsz(softc, data, n, IPFOBJ_IPNAT,
1184 					     n->in_size);
1185 			if (error) {
1186 				MUTEX_EXIT(&softn->ipf_nat_io);
1187 				goto done;
1188 			}
1189 			n->in_flags |= IPN_PURGE;
1190 		}
1191 		ipf_nat_siocdelnat(softc, softn, n, getlock);
1192 
1193 		MUTEX_EXIT(&softn->ipf_nat_io);
1194 		n = NULL;
1195 		break;
1196 
1197 	case SIOCGNATS :
1198 	    {
1199 		natstat_t *nsp = &softn->ipf_nat_stats;
1200 
1201 		nsp->ns_side[0].ns_table = softn->ipf_nat_table[0];
1202 		nsp->ns_side[1].ns_table = softn->ipf_nat_table[1];
1203 		nsp->ns_list = softn->ipf_nat_list;
1204 		nsp->ns_maptable = softn->ipf_hm_maptable;
1205 		nsp->ns_maplist = softn->ipf_hm_maplist;
1206 		nsp->ns_nattab_sz = softn->ipf_nat_table_sz;
1207 		nsp->ns_nattab_max = softn->ipf_nat_table_max;
1208 		nsp->ns_rultab_sz = softn->ipf_nat_maprules_sz;
1209 		nsp->ns_rdrtab_sz = softn->ipf_nat_rdrrules_sz;
1210 		nsp->ns_hostmap_sz = softn->ipf_nat_hostmap_sz;
1211 		nsp->ns_instances = softn->ipf_nat_instances;
1212 		nsp->ns_ticks = softc->ipf_ticks;
1213 #ifdef IPFILTER_LOGGING
1214 		nsp->ns_log_ok = ipf_log_logok(softc, IPF_LOGNAT);
1215 		nsp->ns_log_fail = ipf_log_failures(softc, IPF_LOGNAT);
1216 #else
1217 		nsp->ns_log_ok = 0;
1218 		nsp->ns_log_fail = 0;
1219 #endif
1220 		error = ipf_outobj(softc, data, nsp, IPFOBJ_NATSTAT);
1221 		break;
1222 	    }
1223 
1224 	case SIOCGNATL :
1225 	    {
1226 		natlookup_t nl;
1227 
1228 		error = ipf_inobj(softc, data, NULL, &nl, IPFOBJ_NATLOOKUP);
1229 		if (error == 0) {
1230 			void *ptr;
1231 
1232 			if (getlock) {
1233 				READ_ENTER(&softc->ipf_nat);
1234 			}
1235 
1236 			switch (nl.nl_v)
1237 			{
1238 			case 4 :
1239 				ptr = ipf_nat_lookupredir(softc, &nl);
1240 				break;
1241 #ifdef USE_INET6
1242 			case 6 :
1243 				ptr = ipf_nat6_lookupredir(softc, &nl);
1244 				break;
1245 #endif
1246 			default:
1247 				ptr = NULL;
1248 				break;
1249 			}
1250 
1251 			if (getlock) {
1252 				RWLOCK_EXIT(&softc->ipf_nat);
1253 			}
1254 			if (ptr != NULL) {
1255 				error = ipf_outobj(softc, data, &nl,
1256 						   IPFOBJ_NATLOOKUP);
1257 			} else {
1258 				IPFERROR(60011);
1259 				error = ESRCH;
1260 			}
1261 		}
1262 		break;
1263 	    }
1264 
1265 	case SIOCIPFFL :	/* old SIOCFLNAT & SIOCCNATL */
1266 		if (!(mode & FWRITE)) {
1267 			IPFERROR(60012);
1268 			error = EPERM;
1269 			break;
1270 		}
1271 		if (getlock) {
1272 			WRITE_ENTER(&softc->ipf_nat);
1273 		}
1274 
1275 		error = BCOPYIN(data, &arg, sizeof(arg));
1276 		if (error != 0) {
1277 			IPFERROR(60013);
1278 			error = EFAULT;
1279 		} else {
1280 			if (arg == 0)
1281 				ret = ipf_nat_flushtable(softc, softn);
1282 			else if (arg == 1)
1283 				ret = ipf_nat_clearlist(softc, softn);
1284 			else
1285 				ret = ipf_nat_extraflush(softc, softn, arg);
1286 			ipf_proxy_flush(softc->ipf_proxy_soft, arg);
1287 		}
1288 
1289 		if (getlock) {
1290 			RWLOCK_EXIT(&softc->ipf_nat);
1291 		}
1292 		if (error == 0) {
1293 			error = BCOPYOUT(&ret, data, sizeof(ret));
1294 		}
1295 		break;
1296 
1297 	case SIOCMATCHFLUSH :
1298 		if (!(mode & FWRITE)) {
1299 			IPFERROR(60014);
1300 			error = EPERM;
1301 			break;
1302 		}
1303 		if (getlock) {
1304 			WRITE_ENTER(&softc->ipf_nat);
1305 		}
1306 
1307 		error = ipf_nat_matchflush(softc, softn, data);
1308 
1309 		if (getlock) {
1310 			RWLOCK_EXIT(&softc->ipf_nat);
1311 		}
1312 		break;
1313 
1314 	case SIOCPROXY :
1315 		error = ipf_proxy_ioctl(softc, data, cmd, mode, ctx);
1316 		break;
1317 
1318 	case SIOCSTLCK :
1319 		if (!(mode & FWRITE)) {
1320 			IPFERROR(60015);
1321 			error = EPERM;
1322 		} else {
1323 			error = ipf_lock(data, &softn->ipf_nat_lock);
1324 		}
1325 		break;
1326 
1327 	case SIOCSTPUT :
1328 		if ((mode & FWRITE) != 0) {
1329 			error = ipf_nat_putent(softc, data, getlock);
1330 		} else {
1331 			IPFERROR(60016);
1332 			error = EACCES;
1333 		}
1334 		break;
1335 
1336 	case SIOCSTGSZ :
1337 		if (softn->ipf_nat_lock) {
1338 			error = ipf_nat_getsz(softc, data, getlock);
1339 		} else {
1340 			IPFERROR(60017);
1341 			error = EACCES;
1342 		}
1343 		break;
1344 
1345 	case SIOCSTGET :
1346 		if (softn->ipf_nat_lock) {
1347 			error = ipf_nat_getent(softc, data, getlock);
1348 		} else {
1349 			IPFERROR(60018);
1350 			error = EACCES;
1351 		}
1352 		break;
1353 
1354 	case SIOCGENITER :
1355 	    {
1356 		ipfgeniter_t iter;
1357 		ipftoken_t *token;
1358 		ipfobj_t obj;
1359 
1360 		error = ipf_inobj(softc, data, &obj, &iter, IPFOBJ_GENITER);
1361 		if (error != 0)
1362 			break;
1363 
1364 		SPL_SCHED(s);
1365 		token = ipf_token_find(softc, iter.igi_type, uid, ctx);
1366 		if (token != NULL) {
1367 			error  = ipf_nat_iterator(softc, token, &iter, &obj);
1368 			WRITE_ENTER(&softc->ipf_tokens);
1369 			ipf_token_deref(softc, token);
1370 			RWLOCK_EXIT(&softc->ipf_tokens);
1371 		}
1372 		SPL_X(s);
1373 		break;
1374 	    }
1375 
1376 	case SIOCIPFDELTOK :
1377 		error = BCOPYIN(data, &arg, sizeof(arg));
1378 		if (error == 0) {
1379 			SPL_SCHED(s);
1380 			error = ipf_token_del(softc, arg, uid, ctx);
1381 			SPL_X(s);
1382 		} else {
1383 			IPFERROR(60019);
1384 			error = EFAULT;
1385 		}
1386 		break;
1387 
1388 	case SIOCGTQTAB :
1389 		error = ipf_outobj(softc, data, softn->ipf_nat_tcptq,
1390 				   IPFOBJ_STATETQTAB);
1391 		break;
1392 
1393 	case SIOCGTABL :
1394 		error = ipf_nat_gettable(softc, softn, data);
1395 		break;
1396 
1397 	default :
1398 		IPFERROR(60020);
1399 		error = EINVAL;
1400 		break;
1401 	}
1402 done:
1403 	if (nat != NULL)
1404 		ipf_nat_rule_fini(softc, nat);
1405 	if (natd != NULL)
1406 		KFREE(natd);
1407 	if (nt != NULL)
1408 		KFREES(nt, nt->in_size);
1409 	return error;
1410 }
1411 
1412 
1413 /* ------------------------------------------------------------------------ */
1414 /* Function:    ipf_nat_siocaddnat                                          */
1415 /* Returns:     int - 0 == success, != 0 == failure                         */
1416 /* Parameters:  softc(I) - pointer to soft context main structure           */
1417 /*              softn(I) - pointer to NAT context structure                 */
1418 /*              n(I)       - pointer to new NAT rule                        */
1419 /*              np(I)      - pointer to where to insert new NAT rule        */
1420 /*              getlock(I) - flag indicating if lock on  is held            */
1421 /* Mutex Locks: ipf_nat_io                                                  */
1422 /*                                                                          */
1423 /* Handle SIOCADNAT.  Resolve and calculate details inside the NAT rule     */
1424 /* from information passed to the kernel, then add it  to the appropriate   */
1425 /* NAT rule table(s).                                                       */
1426 /* ------------------------------------------------------------------------ */
1427 static int
ipf_nat_siocaddnat(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,ipnat_t * n,int getlock)1428 ipf_nat_siocaddnat(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, ipnat_t *n,
1429 	int getlock)
1430 {
1431 	int error = 0;
1432 
1433 	if (ipf_nat_resolverule(softc, n) != 0) {
1434 		IPFERROR(60022);
1435 		return ENOENT;
1436 	}
1437 
1438 	if ((n->in_age[0] == 0) && (n->in_age[1] != 0)) {
1439 		IPFERROR(60023);
1440 		return EINVAL;
1441 	}
1442 
1443 	if (n->in_redir == (NAT_DIVERTUDP|NAT_MAP)) {
1444 		/*
1445 		 * Prerecord whether or not the destination of the divert
1446 		 * is local or not to the interface the packet is going
1447 		 * to be sent out.
1448 		 */
1449 		n->in_dlocal = ipf_deliverlocal(softc, n->in_v[1],
1450 						n->in_ifps[1], &n->in_ndstip6);
1451 	}
1452 
1453 	if (getlock) {
1454 		WRITE_ENTER(&softc->ipf_nat);
1455 	}
1456 	n->in_next = NULL;
1457 	n->in_pnext = softn->ipf_nat_list_tail;
1458 	*n->in_pnext = n;
1459 	softn->ipf_nat_list_tail = &n->in_next;
1460 	n->in_use++;
1461 
1462 	if (n->in_redir & NAT_REDIRECT) {
1463 		n->in_flags &= ~IPN_NOTDST;
1464 		switch (n->in_v[0])
1465 		{
1466 		case 4 :
1467 			ipf_nat_addrdr(softn, n);
1468 			break;
1469 #ifdef USE_INET6
1470 		case 6 :
1471 			ipf_nat6_addrdr(softn, n);
1472 			break;
1473 #endif
1474 		default :
1475 			break;
1476 		}
1477 		ATOMIC_INC32(softn->ipf_nat_stats.ns_rules_rdr);
1478 	}
1479 
1480 	if (n->in_redir & (NAT_MAP|NAT_MAPBLK)) {
1481 		n->in_flags &= ~IPN_NOTSRC;
1482 		switch (n->in_v[0])
1483 		{
1484 		case 4 :
1485 			ipf_nat_addmap(softn, n);
1486 			break;
1487 #ifdef USE_INET6
1488 		case 6 :
1489 			ipf_nat6_addmap(softn, n);
1490 			break;
1491 #endif
1492 		default :
1493 			break;
1494 		}
1495 		ATOMIC_INC32(softn->ipf_nat_stats.ns_rules_map);
1496 	}
1497 
1498 	if (n->in_age[0] != 0)
1499 		n->in_tqehead[0] = ipf_addtimeoutqueue(softc,
1500 						       &softn->ipf_nat_utqe,
1501 						       n->in_age[0]);
1502 
1503 	if (n->in_age[1] != 0)
1504 		n->in_tqehead[1] = ipf_addtimeoutqueue(softc,
1505 						       &softn->ipf_nat_utqe,
1506 						       n->in_age[1]);
1507 
1508 	MUTEX_INIT(&n->in_lock, "ipnat rule lock");
1509 
1510 	n = NULL;
1511 	ATOMIC_INC32(softn->ipf_nat_stats.ns_rules);
1512 #if SOLARIS && !defined(INSTANCES)
1513 	pfil_delayed_copy = 0;
1514 #endif
1515 	if (getlock) {
1516 		RWLOCK_EXIT(&softc->ipf_nat);			/* WRITE */
1517 	}
1518 
1519 	return error;
1520 }
1521 
1522 
1523 /* ------------------------------------------------------------------------ */
1524 /* Function:    ipf_nat_ruleaddrinit                                        */
1525 /* Parameters:  softc(I) - pointer to soft context main structure           */
1526 /*              softn(I) - pointer to NAT context structure                 */
1527 /*              n(I)     - pointer to NAT rule                              */
1528 /*                                                                          */
1529 /* Initialise all of the NAT address structures in a NAT rule.              */
1530 /* ------------------------------------------------------------------------ */
1531 static int
ipf_nat_ruleaddrinit(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,ipnat_t * n)1532 ipf_nat_ruleaddrinit(ipf_main_softc_t *softc, ipf_nat_softc_t *softn,
1533     ipnat_t *n)
1534 {
1535 	int idx, error;
1536 
1537 	if ((n->in_ndst.na_atype == FRI_LOOKUP) &&
1538 	    (n->in_ndst.na_type != IPLT_DSTLIST)) {
1539 		IPFERROR(60071);
1540 		return EINVAL;
1541 	}
1542 	if ((n->in_nsrc.na_atype == FRI_LOOKUP) &&
1543 	    (n->in_nsrc.na_type != IPLT_DSTLIST)) {
1544 		IPFERROR(60069);
1545 		return EINVAL;
1546 	}
1547 
1548 	if (n->in_redir == NAT_BIMAP) {
1549 		n->in_ndstaddr = n->in_osrcaddr;
1550 		n->in_ndstmsk = n->in_osrcmsk;
1551 		n->in_odstaddr = n->in_nsrcaddr;
1552 		n->in_odstmsk = n->in_nsrcmsk;
1553 
1554 	}
1555 
1556 	if (n->in_redir & NAT_REDIRECT)
1557 		idx = 1;
1558 	else
1559 		idx = 0;
1560 	/*
1561 	 * Initialise all of the address fields.
1562 	 */
1563 	error = ipf_nat_nextaddrinit(softc, n->in_names, &n->in_osrc, 1,
1564 				     n->in_ifps[idx]);
1565 	if (error != 0)
1566 		return error;
1567 
1568 	error = ipf_nat_nextaddrinit(softc, n->in_names, &n->in_odst, 1,
1569 				     n->in_ifps[idx]);
1570 	if (error != 0)
1571 		return error;
1572 
1573 	error = ipf_nat_nextaddrinit(softc, n->in_names, &n->in_nsrc, 1,
1574 				     n->in_ifps[idx]);
1575 	if (error != 0)
1576 		return error;
1577 
1578 	error = ipf_nat_nextaddrinit(softc, n->in_names, &n->in_ndst, 1,
1579 				     n->in_ifps[idx]);
1580 	if (error != 0)
1581 		return error;
1582 
1583 	if (n->in_redir & NAT_DIVERTUDP)
1584 		ipf_nat_builddivertmp(softn, n);
1585 
1586 	return 0;
1587 }
1588 
1589 
1590 /* ------------------------------------------------------------------------ */
1591 /* Function:    ipf_nat_resolvrule                                          */
1592 /* Returns:     Nil                                                         */
1593 /* Parameters:  softc(I) - pointer to soft context main structure           */
1594 /*              n(I)     - pointer to NAT rule                              */
1595 /*                                                                          */
1596 /* Handle SIOCADNAT.  Resolve and calculate details inside the NAT rule     */
1597 /* from information passed to the kernel, then add it  to the appropriate   */
1598 /* NAT rule table(s).                                                       */
1599 /* ------------------------------------------------------------------------ */
1600 static int
ipf_nat_resolverule(ipf_main_softc_t * softc,ipnat_t * n)1601 ipf_nat_resolverule(ipf_main_softc_t *softc, ipnat_t *n)
1602 {
1603 	char *base;
1604 
1605 	base = n->in_names;
1606 
1607 	n->in_ifps[0] = ipf_resolvenic(softc, base + n->in_ifnames[0],
1608 				       n->in_v[0]);
1609 
1610 	if (n->in_ifnames[1] == -1) {
1611 		n->in_ifnames[1] = n->in_ifnames[0];
1612 		n->in_ifps[1] = n->in_ifps[0];
1613 	} else {
1614 		n->in_ifps[1] = ipf_resolvenic(softc, base + n->in_ifnames[1],
1615 					       n->in_v[1]);
1616 	}
1617 
1618 	if (n->in_plabel != -1) {
1619 		if (n->in_redir & NAT_REDIRECT)
1620 			n->in_apr = ipf_proxy_lookup(softc->ipf_proxy_soft,
1621 						     n->in_pr[0],
1622 						     base + n->in_plabel);
1623 		else
1624 			n->in_apr = ipf_proxy_lookup(softc->ipf_proxy_soft,
1625 						     n->in_pr[1],
1626 						     base + n->in_plabel);
1627 		if (n->in_apr == NULL)
1628 			return -1;
1629 	}
1630 	return 0;
1631 }
1632 
1633 
1634 /* ------------------------------------------------------------------------ */
1635 /* Function:    ipf_nat_siocdelnat                                          */
1636 /* Returns:     int - 0 == success, != 0 == failure                         */
1637 /* Parameters:  softc(I)   - pointer to soft context main structure         */
1638 /*              softn(I)   - pointer to NAT context structure               */
1639 /*              n(I)       - pointer to new NAT rule                        */
1640 /*              getlock(I) - flag indicating if lock on  is held            */
1641 /* Mutex Locks: ipf_nat_io                                                  */
1642 /*                                                                          */
1643 /* Handle SIOCADNAT.  Resolve and calculate details inside the NAT rule     */
1644 /* from information passed to the kernel, then add it  to the appropriate   */
1645 /* NAT rule table(s).                                                       */
1646 /* ------------------------------------------------------------------------ */
1647 static void
ipf_nat_siocdelnat(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,ipnat_t * n,int getlock)1648 ipf_nat_siocdelnat(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, ipnat_t *n,
1649 	int getlock)
1650 {
1651 #ifdef IPF_NAT6
1652 	int i;
1653 #endif
1654 
1655 	if (getlock) {
1656 		WRITE_ENTER(&softc->ipf_nat);
1657 	}
1658 
1659 	ipf_nat_delrule(softc, softn, n, 1);
1660 
1661 	if (getlock) {
1662 		RWLOCK_EXIT(&softc->ipf_nat);			/* READ/WRITE */
1663 	}
1664 }
1665 
1666 
1667 /* ------------------------------------------------------------------------ */
1668 /* Function:    ipf_nat_getsz                                               */
1669 /* Returns:     int - 0 == success, != 0 is the error value.                */
1670 /* Parameters:  softc(I)   - pointer to soft context main structure         */
1671 /*              data(I)    - pointer to natget structure with kernel        */
1672 /*                           pointer get the size of.                       */
1673 /*              getlock(I) - flag indicating whether or not the caller      */
1674 /*                           holds a lock on ipf_nat                        */
1675 /*                                                                          */
1676 /* Handle SIOCSTGSZ.                                                        */
1677 /* Return the size of the nat list entry to be copied back to user space.   */
1678 /* The size of the entry is stored in the ng_sz field and the enture natget */
1679 /* structure is copied back to the user.                                    */
1680 /* ------------------------------------------------------------------------ */
1681 static int
ipf_nat_getsz(ipf_main_softc_t * softc,void * data,int getlock)1682 ipf_nat_getsz(ipf_main_softc_t *softc, void *data, int getlock)
1683 {
1684 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
1685 	ap_session_t *aps;
1686 	nat_t *nat, *n;
1687 	natget_t ng;
1688 	int error;
1689 
1690 	error = BCOPYIN(data, &ng, sizeof(ng));
1691 	if (error != 0) {
1692 		IPFERROR(60024);
1693 		return EFAULT;
1694 	}
1695 
1696 	if (getlock) {
1697 		READ_ENTER(&softc->ipf_nat);
1698 	}
1699 
1700 	nat = ng.ng_ptr;
1701 	if (!nat) {
1702 		nat = softn->ipf_nat_instances;
1703 		ng.ng_sz = 0;
1704 		/*
1705 		 * Empty list so the size returned is 0.  Simple.
1706 		 */
1707 		if (nat == NULL) {
1708 			if (getlock) {
1709 				RWLOCK_EXIT(&softc->ipf_nat);
1710 			}
1711 			error = BCOPYOUT(&ng, data, sizeof(ng));
1712 			if (error != 0) {
1713 				IPFERROR(60025);
1714 				return EFAULT;
1715 			}
1716 			return 0;
1717 		}
1718 	} else {
1719 		/*
1720 		 * Make sure the pointer we're copying from exists in the
1721 		 * current list of entries.  Security precaution to prevent
1722 		 * copying of random kernel data.
1723 		 */
1724 		for (n = softn->ipf_nat_instances; n; n = n->nat_next)
1725 			if (n == nat)
1726 				break;
1727 		if (n == NULL) {
1728 			if (getlock) {
1729 				RWLOCK_EXIT(&softc->ipf_nat);
1730 			}
1731 			IPFERROR(60026);
1732 			return ESRCH;
1733 		}
1734 	}
1735 
1736 	/*
1737 	 * Include any space required for proxy data structures.
1738 	 */
1739 	ng.ng_sz = sizeof(nat_save_t);
1740 	aps = nat->nat_aps;
1741 	if (aps != NULL) {
1742 		ng.ng_sz += sizeof(ap_session_t) - 4;
1743 		if (aps->aps_data != 0)
1744 			ng.ng_sz += aps->aps_psiz;
1745 	}
1746 	if (getlock) {
1747 		RWLOCK_EXIT(&softc->ipf_nat);
1748 	}
1749 
1750 	error = BCOPYOUT(&ng, data, sizeof(ng));
1751 	if (error != 0) {
1752 		IPFERROR(60027);
1753 		return EFAULT;
1754 	}
1755 	return 0;
1756 }
1757 
1758 
1759 /* ------------------------------------------------------------------------ */
1760 /* Function:    ipf_nat_getent                                              */
1761 /* Returns:     int - 0 == success, != 0 is the error value.                */
1762 /* Parameters:  softc(I)   - pointer to soft context main structure         */
1763 /*              data(I)    - pointer to natget structure with kernel pointer*/
1764 /*                           to NAT structure to copy out.                  */
1765 /*              getlock(I) - flag indicating whether or not the caller      */
1766 /*                           holds a lock on ipf_nat                        */
1767 /*                                                                          */
1768 /* Handle SIOCSTGET.                                                        */
1769 /* Copies out NAT entry to user space.  Any additional data held for a      */
1770 /* proxy is also copied, as to is the NAT rule which was responsible for it */
1771 /* ------------------------------------------------------------------------ */
1772 static int
ipf_nat_getent(ipf_main_softc_t * softc,void * data,int getlock)1773 ipf_nat_getent(ipf_main_softc_t *softc, void *data, int getlock)
1774 {
1775 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
1776 	int error, outsize;
1777 	ap_session_t *aps;
1778 	nat_save_t *ipn, ipns;
1779 	nat_t *n, *nat;
1780 
1781 	error = ipf_inobj(softc, data, NULL, &ipns, IPFOBJ_NATSAVE);
1782 	if (error != 0)
1783 		return error;
1784 
1785 	if ((ipns.ipn_dsize < sizeof(ipns)) || (ipns.ipn_dsize > 81920)) {
1786 		IPFERROR(60028);
1787 		return EINVAL;
1788 	}
1789 
1790 	KMALLOCS(ipn, nat_save_t *, ipns.ipn_dsize);
1791 	if (ipn == NULL) {
1792 		IPFERROR(60029);
1793 		return ENOMEM;
1794 	}
1795 
1796 	if (getlock) {
1797 		READ_ENTER(&softc->ipf_nat);
1798 	}
1799 
1800 	ipn->ipn_dsize = ipns.ipn_dsize;
1801 	nat = ipns.ipn_next;
1802 	if (nat == NULL) {
1803 		nat = softn->ipf_nat_instances;
1804 		if (nat == NULL) {
1805 			if (softn->ipf_nat_instances == NULL) {
1806 				IPFERROR(60030);
1807 				error = ENOENT;
1808 			}
1809 			goto finished;
1810 		}
1811 	} else {
1812 		/*
1813 		 * Make sure the pointer we're copying from exists in the
1814 		 * current list of entries.  Security precaution to prevent
1815 		 * copying of random kernel data.
1816 		 */
1817 		for (n = softn->ipf_nat_instances; n; n = n->nat_next)
1818 			if (n == nat)
1819 				break;
1820 		if (n == NULL) {
1821 			IPFERROR(60031);
1822 			error = ESRCH;
1823 			goto finished;
1824 		}
1825 	}
1826 	ipn->ipn_next = nat->nat_next;
1827 
1828 	/*
1829 	 * Copy the NAT structure.
1830 	 */
1831 	bcopy((char *)nat, &ipn->ipn_nat, sizeof(*nat));
1832 
1833 	/*
1834 	 * If we have a pointer to the NAT rule it belongs to, save that too.
1835 	 */
1836 	if (nat->nat_ptr != NULL)
1837 		bcopy((char *)nat->nat_ptr, (char *)&ipn->ipn_ipnat,
1838 		      ipn->ipn_ipnat.in_size);
1839 
1840 	/*
1841 	 * If we also know the NAT entry has an associated filter rule,
1842 	 * save that too.
1843 	 */
1844 	if (nat->nat_fr != NULL)
1845 		bcopy((char *)nat->nat_fr, (char *)&ipn->ipn_fr,
1846 		      sizeof(ipn->ipn_fr));
1847 
1848 	/*
1849 	 * Last but not least, if there is an application proxy session set
1850 	 * up for this NAT entry, then copy that out too, including any
1851 	 * private data saved along side it by the proxy.
1852 	 */
1853 	aps = nat->nat_aps;
1854 	outsize = ipn->ipn_dsize - sizeof(*ipn) + sizeof(ipn->ipn_data);
1855 	if (aps != NULL) {
1856 		char *s;
1857 
1858 		if (outsize < sizeof(*aps)) {
1859 			IPFERROR(60032);
1860 			error = ENOBUFS;
1861 			goto finished;
1862 		}
1863 
1864 		s = ipn->ipn_data;
1865 		bcopy((char *)aps, s, sizeof(*aps));
1866 		s += sizeof(*aps);
1867 		outsize -= sizeof(*aps);
1868 		if ((aps->aps_data != NULL) && (outsize >= aps->aps_psiz))
1869 			bcopy(aps->aps_data, s, aps->aps_psiz);
1870 		else {
1871 			IPFERROR(60033);
1872 			error = ENOBUFS;
1873 		}
1874 	}
1875 	if (error == 0) {
1876 		if (getlock) {
1877 			READ_ENTER(&softc->ipf_nat);
1878 			getlock = 0;
1879 		}
1880 		error = ipf_outobjsz(softc, data, ipn, IPFOBJ_NATSAVE,
1881 				     ipns.ipn_dsize);
1882 	}
1883 
1884 finished:
1885 	if (getlock) {
1886 		READ_ENTER(&softc->ipf_nat);
1887 	}
1888 	if (ipn != NULL) {
1889 		KFREES(ipn, ipns.ipn_dsize);
1890 	}
1891 	return error;
1892 }
1893 
1894 
1895 /* ------------------------------------------------------------------------ */
1896 /* Function:    ipf_nat_putent                                              */
1897 /* Returns:     int - 0 == success, != 0 is the error value.                */
1898 /* Parameters:  softc(I)   - pointer to soft context main structure         */
1899 /*              data(I)    - pointer to natget structure with NAT           */
1900 /*                           structure information to load into the kernel  */
1901 /*              getlock(I) - flag indicating whether or not a write lock    */
1902 /*                           on is already held.                            */
1903 /*                                                                          */
1904 /* Handle SIOCSTPUT.                                                        */
1905 /* Loads a NAT table entry from user space, including a NAT rule, proxy and */
1906 /* firewall rule data structures, if pointers to them indicate so.          */
1907 /* ------------------------------------------------------------------------ */
1908 static int
ipf_nat_putent(ipf_main_softc_t * softc,void * data,int getlock)1909 ipf_nat_putent(ipf_main_softc_t *softc, void *data, int getlock)
1910 {
1911 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
1912 	nat_save_t *ipn, *ipnn;
1913 	ap_session_t *aps;
1914 	nat_t *n, *nat;
1915 	frentry_t *fr;
1916 	fr_info_t *fin;
1917 	ipnat_t *in;
1918 	int error;
1919 
1920 	KMALLOC(ipn, nat_save_t *);
1921 	if (ipn == NULL)
1922 		return ENOMEM;
1923 	error = ipf_inobj(softc, data, NULL, ipn, IPFOBJ_NATSAVE);
1924 	if (error != 0)
1925 		return error;
1926 
1927 	/*
1928 	 * Initialise early because of code at junkput label.
1929 	 */
1930 	n = NULL;
1931 	in = NULL;
1932 	aps = NULL;
1933 	nat = NULL;
1934 	ipnn = NULL;
1935 	fin = NULL;
1936 	fr = NULL;
1937 
1938 	/*
1939 	 * New entry, copy in the rest of the NAT entry if it's size is more
1940 	 * than just the nat_t structure.
1941 	 */
1942 	if (ipn->ipn_dsize > sizeof(*ipn)) {
1943 		if (ipn->ipn_dsize > 81920) {
1944 			IPFERROR(60034);
1945 			error = ENOMEM;
1946 			goto junkput;
1947 		}
1948 
1949 		KMALLOCS(ipnn, nat_save_t *, ipn->ipn_dsize);
1950 		if (ipnn == NULL) {
1951 			IPFERROR(60035);
1952 			return ENOMEM;
1953 		}
1954 
1955 		bzero(ipnn, ipn->ipn_dsize);
1956 		error = ipf_inobjsz(softc, data, ipnn, IPFOBJ_NATSAVE,
1957 				    ipn->ipn_dsize);
1958 		if (error != 0) {
1959 			goto junkput;
1960 		}
1961 	} else
1962 		ipnn = ipn;
1963 
1964 	KMALLOC(nat, nat_t *);
1965 	if (nat == NULL) {
1966 		IPFERROR(60037);
1967 		error = ENOMEM;
1968 		goto junkput;
1969 	}
1970 
1971 	bcopy((char *)&ipnn->ipn_nat, (char *)nat, sizeof(*nat));
1972 
1973 	switch (nat->nat_v[0])
1974 	{
1975 	case 4:
1976 #ifdef USE_IENT6
1977 	case 6 :
1978 #endif
1979 		break;
1980 	default :
1981 		IPFERROR(60061);
1982 		error = EPROTONOSUPPORT;
1983 		goto junkput;
1984 		/*NOTREACHED*/
1985 	}
1986 
1987 	/*
1988 	 * Initialize all these so that ipf_nat_delete() doesn't cause a crash.
1989 	 */
1990 	bzero((char *)nat, offsetof(struct nat, nat_tqe));
1991 	nat->nat_tqe.tqe_pnext = NULL;
1992 	nat->nat_tqe.tqe_next = NULL;
1993 	nat->nat_tqe.tqe_ifq = NULL;
1994 	nat->nat_tqe.tqe_parent = nat;
1995 
1996 	/*
1997 	 * Restore the rule associated with this nat session
1998 	 */
1999 	in = ipnn->ipn_nat.nat_ptr;
2000 	if (in != NULL) {
2001 		KMALLOCS(in, ipnat_t *, ipnn->ipn_ipnat.in_size);
2002 		nat->nat_ptr = in;
2003 		if (in == NULL) {
2004 			IPFERROR(60038);
2005 			error = ENOMEM;
2006 			goto junkput;
2007 		}
2008 		bcopy((char *)&ipnn->ipn_ipnat, (char *)in,
2009 		      ipnn->ipn_ipnat.in_size);
2010 		in->in_use = 1;
2011 		in->in_flags |= IPN_DELETE;
2012 
2013 		ATOMIC_INC32(softn->ipf_nat_stats.ns_rules);
2014 
2015 		if (ipf_nat_resolverule(softc, in) != 0) {
2016 			IPFERROR(60039);
2017 			error = ESRCH;
2018 			goto junkput;
2019 		}
2020 	}
2021 
2022 	/*
2023 	 * Check that the NAT entry doesn't already exist in the kernel.
2024 	 *
2025 	 * For NAT_OUTBOUND, we're lookup for a duplicate MAP entry.  To do
2026 	 * this, we check to see if the inbound combination of addresses and
2027 	 * ports is already known.  Similar logic is applied for NAT_INBOUND.
2028 	 *
2029 	 */
2030 	KMALLOC(fin, fr_info_t *);
2031 	if (fin == NULL) {
2032 		error = ENOMEM;
2033 		goto junkput;
2034 	}
2035 	bzero(fin, sizeof(*fin));
2036 	fin->fin_v = nat->nat_v[0];
2037 	fin->fin_p = nat->nat_pr[0];
2038 	fin->fin_rev = nat->nat_rev;
2039 	fin->fin_ifp = nat->nat_ifps[0];
2040 	fin->fin_data[0] = ntohs(nat->nat_ndport);
2041 	fin->fin_data[1] = ntohs(nat->nat_nsport);
2042 
2043 	switch (nat->nat_dir)
2044 	{
2045 	case NAT_OUTBOUND :
2046 	case NAT_DIVERTOUT :
2047 		if (getlock) {
2048 			READ_ENTER(&softc->ipf_nat);
2049 		}
2050 
2051 		fin->fin_v = nat->nat_v[1];
2052 		if (nat->nat_v[1] == 4) {
2053 			n = ipf_nat_inlookup(fin, nat->nat_flags, fin->fin_p,
2054 					     nat->nat_ndstip, nat->nat_nsrcip);
2055 #ifdef USE_INET6
2056 		} else if (nat->nat_v[1] == 6) {
2057 			n = ipf_nat6_inlookup(fin, nat->nat_flags, fin->fin_p,
2058 					      &nat->nat_ndst6.in6,
2059 					      &nat->nat_nsrc6.in6);
2060 #endif
2061 		}
2062 
2063 		if (getlock) {
2064 			RWLOCK_EXIT(&softc->ipf_nat);
2065 		}
2066 		if (n != NULL) {
2067 			IPFERROR(60040);
2068 			error = EEXIST;
2069 			goto junkput;
2070 		}
2071 		break;
2072 
2073 	case NAT_INBOUND :
2074 	case NAT_DIVERTIN :
2075 		if (getlock) {
2076 			READ_ENTER(&softc->ipf_nat);
2077 		}
2078 
2079 		if (fin->fin_v == 4) {
2080 			n = ipf_nat_outlookup(fin, nat->nat_flags, fin->fin_p,
2081 					      nat->nat_ndstip,
2082 					      nat->nat_nsrcip);
2083 #ifdef USE_INET6
2084 		} else if (fin->fin_v == 6) {
2085 			n = ipf_nat6_outlookup(fin, nat->nat_flags, fin->fin_p,
2086 					       &nat->nat_ndst6.in6,
2087 					       &nat->nat_nsrc6.in6);
2088 #endif
2089 		}
2090 
2091 		if (getlock) {
2092 			RWLOCK_EXIT(&softc->ipf_nat);
2093 		}
2094 		if (n != NULL) {
2095 			IPFERROR(60041);
2096 			error = EEXIST;
2097 			goto junkput;
2098 		}
2099 		break;
2100 
2101 	default :
2102 		IPFERROR(60042);
2103 		error = EINVAL;
2104 		goto junkput;
2105 	}
2106 
2107 	/*
2108 	 * Restore ap_session_t structure.  Include the private data allocated
2109 	 * if it was there.
2110 	 */
2111 	aps = nat->nat_aps;
2112 	if (aps != NULL) {
2113 		KMALLOC(aps, ap_session_t *);
2114 		nat->nat_aps = aps;
2115 		if (aps == NULL) {
2116 			IPFERROR(60043);
2117 			error = ENOMEM;
2118 			goto junkput;
2119 		}
2120 		bcopy(ipnn->ipn_data, (char *)aps, sizeof(*aps));
2121 		if (in != NULL)
2122 			aps->aps_apr = in->in_apr;
2123 		else
2124 			aps->aps_apr = NULL;
2125 		if (aps->aps_psiz != 0) {
2126 			if (aps->aps_psiz > 81920) {
2127 				IPFERROR(60044);
2128 				error = ENOMEM;
2129 				goto junkput;
2130 			}
2131 			KMALLOCS(aps->aps_data, void *, aps->aps_psiz);
2132 			if (aps->aps_data == NULL) {
2133 				IPFERROR(60045);
2134 				error = ENOMEM;
2135 				goto junkput;
2136 			}
2137 			bcopy(ipnn->ipn_data + sizeof(*aps), aps->aps_data,
2138 			      aps->aps_psiz);
2139 		} else {
2140 			aps->aps_psiz = 0;
2141 			aps->aps_data = NULL;
2142 		}
2143 	}
2144 
2145 	/*
2146 	 * If there was a filtering rule associated with this entry then
2147 	 * build up a new one.
2148 	 */
2149 	fr = nat->nat_fr;
2150 	if (fr != NULL) {
2151 		if ((nat->nat_flags & SI_NEWFR) != 0) {
2152 			KMALLOC(fr, frentry_t *);
2153 			nat->nat_fr = fr;
2154 			if (fr == NULL) {
2155 				IPFERROR(60046);
2156 				error = ENOMEM;
2157 				goto junkput;
2158 			}
2159 			ipnn->ipn_nat.nat_fr = fr;
2160 			fr->fr_ref = 1;
2161 			(void) ipf_outobj(softc, data, ipnn, IPFOBJ_NATSAVE);
2162 			bcopy((char *)&ipnn->ipn_fr, (char *)fr, sizeof(*fr));
2163 
2164 			fr->fr_ref = 1;
2165 			fr->fr_dsize = 0;
2166 			fr->fr_data = NULL;
2167 			fr->fr_type = FR_T_NONE;
2168 
2169 			MUTEX_NUKE(&fr->fr_lock);
2170 			MUTEX_INIT(&fr->fr_lock, "nat-filter rule lock");
2171 		} else {
2172 			if (getlock) {
2173 				READ_ENTER(&softc->ipf_nat);
2174 			}
2175 			for (n = softn->ipf_nat_instances; n; n = n->nat_next)
2176 				if (n->nat_fr == fr)
2177 					break;
2178 
2179 			if (n != NULL) {
2180 				MUTEX_ENTER(&fr->fr_lock);
2181 				fr->fr_ref++;
2182 				MUTEX_EXIT(&fr->fr_lock);
2183 			}
2184 			if (getlock) {
2185 				RWLOCK_EXIT(&softc->ipf_nat);
2186 			}
2187 
2188 			if (n == NULL) {
2189 				IPFERROR(60047);
2190 				error = ESRCH;
2191 				goto junkput;
2192 			}
2193 		}
2194 	}
2195 
2196 	if (ipnn != ipn) {
2197 		KFREES(ipnn, ipn->ipn_dsize);
2198 		ipnn = NULL;
2199 	}
2200 
2201 	if (getlock) {
2202 		WRITE_ENTER(&softc->ipf_nat);
2203 	}
2204 
2205 	if (fin->fin_v == 4)
2206 		error = ipf_nat_finalise(fin, nat);
2207 #ifdef USE_INET6
2208 	else
2209 		error = ipf_nat6_finalise(fin, nat);
2210 #endif
2211 
2212 	if (getlock) {
2213 		RWLOCK_EXIT(&softc->ipf_nat);
2214 	}
2215 
2216 	if (error == 0)
2217 		return 0;
2218 
2219 	IPFERROR(60048);
2220 	error = ENOMEM;
2221 
2222 junkput:
2223 	if (fin != NULL)
2224 		KFREE(fin);
2225 	if (fr != NULL) {
2226 		(void) ipf_derefrule(softc, &fr);
2227 	}
2228 
2229 	if ((ipnn != NULL) && (ipnn != ipn)) {
2230 		KFREES(ipnn, ipn->ipn_dsize);
2231 	}
2232 	if (ipn != NULL)
2233 		KFREE(ipn);
2234 	if (nat != NULL) {
2235 		if (aps != NULL) {
2236 			if (aps->aps_data != NULL) {
2237 				KFREES(aps->aps_data, aps->aps_psiz);
2238 			}
2239 			KFREE(aps);
2240 		}
2241 		if (in != NULL) {
2242 			if (in->in_apr)
2243 				ipf_proxy_deref(in->in_apr);
2244 			KFREES(in, in->in_size);
2245 		}
2246 		KFREE(nat);
2247 	}
2248 	return error;
2249 }
2250 
2251 
2252 /* ------------------------------------------------------------------------ */
2253 /* Function:    ipf_nat_delete                                              */
2254 /* Returns:     Nil                                                         */
2255 /* Parameters:  softc(I)   - pointer to soft context main structure         */
2256 /*              nat(I)     - pointer to NAT structure to delete             */
2257 /*              logtype(I) - type of LOG record to create before deleting   */
2258 /* Write Lock:  ipf_nat                                                     */
2259 /*                                                                          */
2260 /* Delete a nat entry from the various lists and table.  If NAT logging is  */
2261 /* enabled then generate a NAT log record for this event.                   */
2262 /* ------------------------------------------------------------------------ */
2263 void
ipf_nat_delete(ipf_main_softc_t * softc,struct nat * nat,int logtype)2264 ipf_nat_delete(ipf_main_softc_t *softc, struct nat *nat, int logtype)
2265 {
2266 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
2267 	int madeorphan = 0, removed = 0;
2268 	u_int bkt;
2269 	nat_stat_side_t *nss;
2270 	struct ipnat *ipn;
2271 
2272 	if (logtype != 0 && softn->ipf_nat_logging != 0)
2273 		ipf_nat_log(softc, softn, nat, logtype);
2274 
2275 	/*
2276 	 * Take it as a general indication that all the pointers are set if
2277 	 * nat_pnext is set.
2278 	 */
2279 	if (nat->nat_pnext != NULL) {
2280 		removed = 1;
2281 
2282 		bkt = nat->nat_hv[0] % softn->ipf_nat_table_sz;
2283 		nss = &softn->ipf_nat_stats.ns_side[0];
2284 		ASSERT(nss->ns_bucketlen[bkt] > 0);
2285 		nss->ns_bucketlen[bkt]--;
2286 		if (nss->ns_bucketlen[bkt] == 0) {
2287 			nss->ns_inuse--;
2288 		}
2289 
2290 		bkt = nat->nat_hv[1] % softn->ipf_nat_table_sz;
2291 		nss = &softn->ipf_nat_stats.ns_side[1];
2292 		ASSERT(nss->ns_bucketlen[bkt] > 0);
2293 		nss->ns_bucketlen[bkt]--;
2294 		if (nss->ns_bucketlen[bkt] == 0) {
2295 			nss->ns_inuse--;
2296 		}
2297 
2298 		*nat->nat_pnext = nat->nat_next;
2299 		if (nat->nat_next != NULL) {
2300 			nat->nat_next->nat_pnext = nat->nat_pnext;
2301 			nat->nat_next = NULL;
2302 		}
2303 		nat->nat_pnext = NULL;
2304 
2305 		*nat->nat_phnext[0] = nat->nat_hnext[0];
2306 		if (nat->nat_hnext[0] != NULL) {
2307 			nat->nat_hnext[0]->nat_phnext[0] = nat->nat_phnext[0];
2308 			nat->nat_hnext[0] = NULL;
2309 		}
2310 		nat->nat_phnext[0] = NULL;
2311 
2312 		*nat->nat_phnext[1] = nat->nat_hnext[1];
2313 		if (nat->nat_hnext[1] != NULL) {
2314 			nat->nat_hnext[1]->nat_phnext[1] = nat->nat_phnext[1];
2315 			nat->nat_hnext[1] = NULL;
2316 		}
2317 		nat->nat_phnext[1] = NULL;
2318 
2319 		if ((nat->nat_flags & SI_WILDP) != 0) {
2320 			ATOMIC_DEC32(softn->ipf_nat_stats.ns_wilds);
2321 		}
2322 		madeorphan = 1;
2323 	}
2324 
2325 	if (nat->nat_me != NULL) {
2326 		*nat->nat_me = NULL;
2327 		nat->nat_me = NULL;
2328 		nat->nat_ref--;
2329 		ASSERT(nat->nat_ref >= 0);
2330 	}
2331 
2332 	if (nat->nat_tqe.tqe_ifq != NULL) {
2333 		/*
2334 		 * No call to ipf_freetimeoutqueue() is made here, they are
2335 		 * garbage collected in ipf_nat_expire().
2336 		 */
2337 		(void) ipf_deletequeueentry(&nat->nat_tqe);
2338 	}
2339 
2340 	if (nat->nat_sync) {
2341 		ipf_sync_del_nat(softc->ipf_sync_soft, nat->nat_sync);
2342 		nat->nat_sync = NULL;
2343 	}
2344 
2345 	if (logtype == NL_EXPIRE)
2346 		softn->ipf_nat_stats.ns_expire++;
2347 
2348 	MUTEX_ENTER(&nat->nat_lock);
2349 	/*
2350 	 * NL_DESTROY should only be passed in when we've got nat_ref >= 2.
2351 	 * This happens when a nat'd packet is blocked and we want to throw
2352 	 * away the NAT session.
2353 	 */
2354 	if (logtype == NL_DESTROY) {
2355 		if (nat->nat_ref > 2) {
2356 			nat->nat_ref -= 2;
2357 			MUTEX_EXIT(&nat->nat_lock);
2358 			if (removed)
2359 				softn->ipf_nat_stats.ns_orphans++;
2360 			return;
2361 		}
2362 	} else if (nat->nat_ref > 1) {
2363 		nat->nat_ref--;
2364 		MUTEX_EXIT(&nat->nat_lock);
2365 		if (madeorphan == 1)
2366 			softn->ipf_nat_stats.ns_orphans++;
2367 		return;
2368 	}
2369 	ASSERT(nat->nat_ref >= 0);
2370 	MUTEX_EXIT(&nat->nat_lock);
2371 
2372 	nat->nat_ref = 0;
2373 
2374 	if (madeorphan == 0)
2375 		softn->ipf_nat_stats.ns_orphans--;
2376 
2377 	/*
2378 	 * At this point, nat_ref can be either 0 or -1
2379 	 */
2380 	softn->ipf_nat_stats.ns_proto[nat->nat_pr[0]]--;
2381 
2382 	if (nat->nat_fr != NULL) {
2383 		(void) ipf_derefrule(softc, &nat->nat_fr);
2384 	}
2385 
2386 	if (nat->nat_hm != NULL) {
2387 		ipf_nat_hostmapdel(softc, &nat->nat_hm);
2388 	}
2389 
2390 	/*
2391 	 * If there is an active reference from the nat entry to its parent
2392 	 * rule, decrement the rule's reference count and free it too if no
2393 	 * longer being used.
2394 	 */
2395 	ipn = nat->nat_ptr;
2396 	nat->nat_ptr = NULL;
2397 
2398 	if (ipn != NULL) {
2399 		ipn->in_space++;
2400 		ipf_nat_rule_deref(softc, &ipn);
2401 	}
2402 
2403 	if (nat->nat_aps != NULL) {
2404 		ipf_proxy_free(softc, nat->nat_aps);
2405 		nat->nat_aps = NULL;
2406 	}
2407 
2408 	MUTEX_DESTROY(&nat->nat_lock);
2409 
2410 	softn->ipf_nat_stats.ns_active--;
2411 
2412 	/*
2413 	 * If there's a fragment table entry too for this nat entry, then
2414 	 * dereference that as well.  This is after nat_lock is released
2415 	 * because of Tru64.
2416 	 */
2417 	ipf_frag_natforget(softc, (void *)nat);
2418 
2419 	KFREE(nat);
2420 }
2421 
2422 
2423 /* ------------------------------------------------------------------------ */
2424 /* Function:    ipf_nat_flushtable                                          */
2425 /* Returns:     int - number of NAT rules deleted                           */
2426 /* Parameters:  softc(I) - pointer to soft context main structure           */
2427 /*              softn(I) - pointer to NAT context structure                 */
2428 /* Write Lock:  ipf_nat                                                     */
2429 /*                                                                          */
2430 /* Deletes all currently active NAT sessions.  In deleting each NAT entry a */
2431 /* log record should be emitted in ipf_nat_delete() if NAT logging is       */
2432 /* enabled.                                                                 */
2433 /* ------------------------------------------------------------------------ */
2434 /*
2435  * nat_flushtable - clear the NAT table of all mapping entries.
2436  */
2437 static int
ipf_nat_flushtable(ipf_main_softc_t * softc,ipf_nat_softc_t * softn)2438 ipf_nat_flushtable(ipf_main_softc_t *softc, ipf_nat_softc_t *softn)
2439 {
2440 	nat_t *nat;
2441 	int j = 0;
2442 
2443 	/*
2444 	 * ALL NAT mappings deleted, so lets just make the deletions
2445 	 * quicker.
2446 	 */
2447 	if (softn->ipf_nat_table[0] != NULL)
2448 		bzero((char *)softn->ipf_nat_table[0],
2449 		      sizeof(softn->ipf_nat_table[0]) *
2450 		      softn->ipf_nat_table_sz);
2451 	if (softn->ipf_nat_table[1] != NULL)
2452 		bzero((char *)softn->ipf_nat_table[1],
2453 		      sizeof(softn->ipf_nat_table[1]) *
2454 		      softn->ipf_nat_table_sz);
2455 
2456 	while ((nat = softn->ipf_nat_instances) != NULL) {
2457 		ipf_nat_delete(softc, nat, NL_FLUSH);
2458 		j++;
2459 	}
2460 
2461 	return j;
2462 }
2463 
2464 
2465 /* ------------------------------------------------------------------------ */
2466 /* Function:    ipf_nat_clearlist                                           */
2467 /* Returns:     int - number of NAT/RDR rules deleted                       */
2468 /* Parameters:  softc(I) - pointer to soft context main structure           */
2469 /*              softn(I) - pointer to NAT context structure                 */
2470 /*                                                                          */
2471 /* Delete all rules in the current list of rules.  There is nothing elegant */
2472 /* about this cleanup: simply free all entries on the list of rules and     */
2473 /* clear out the tables used for hashed NAT rule lookups.                   */
2474 /* ------------------------------------------------------------------------ */
2475 static int
ipf_nat_clearlist(ipf_main_softc_t * softc,ipf_nat_softc_t * softn)2476 ipf_nat_clearlist(ipf_main_softc_t *softc, ipf_nat_softc_t *softn)
2477 {
2478 	ipnat_t *n;
2479 	int i = 0;
2480 
2481 	if (softn->ipf_nat_map_rules != NULL) {
2482 		bzero((char *)softn->ipf_nat_map_rules,
2483 		      sizeof(*softn->ipf_nat_map_rules) *
2484 		      softn->ipf_nat_maprules_sz);
2485 	}
2486 	if (softn->ipf_nat_rdr_rules != NULL) {
2487 		bzero((char *)softn->ipf_nat_rdr_rules,
2488 		      sizeof(*softn->ipf_nat_rdr_rules) *
2489 		      softn->ipf_nat_rdrrules_sz);
2490 	}
2491 
2492 	while ((n = softn->ipf_nat_list) != NULL) {
2493 		ipf_nat_delrule(softc, softn, n, 0);
2494 		i++;
2495 	}
2496 #if SOLARIS && !defined(INSTANCES)
2497 	pfil_delayed_copy = 1;
2498 #endif
2499 	return i;
2500 }
2501 
2502 
2503 /* ------------------------------------------------------------------------ */
2504 /* Function:    ipf_nat_delrule                                             */
2505 /* Returns:     Nil                                                         */
2506 /* Parameters:  softc(I) - pointer to soft context main structure           */
2507 /*              softn(I) - pointer to NAT context structure                 */
2508 /*              np(I)    - pointer to NAT rule to delete                    */
2509 /*              purge(I) - 1 == allow purge, 0 == prevent purge             */
2510 /* Locks:       WRITE(ipf_nat)                                              */
2511 /*                                                                          */
2512 /* Preventing "purge" from occuring is allowed because when all of the NAT  */
2513 /* rules are being removed, allowing the "purge" to walk through the list   */
2514 /* of NAT sessions, possibly multiple times, would be a large performance   */
2515 /* hit, on the order of O(N^2).                                             */
2516 /* ------------------------------------------------------------------------ */
2517 static void
ipf_nat_delrule(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,ipnat_t * np,int purge)2518 ipf_nat_delrule(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, ipnat_t *np,
2519 	int purge)
2520 {
2521 
2522 	if (np->in_pnext != NULL) {
2523 		*np->in_pnext = np->in_next;
2524 		if (np->in_next != NULL)
2525 			np->in_next->in_pnext = np->in_pnext;
2526 		if (softn->ipf_nat_list_tail == &np->in_next)
2527 			softn->ipf_nat_list_tail = np->in_pnext;
2528 	}
2529 
2530 	if ((purge == 1) && ((np->in_flags & IPN_PURGE) != 0)) {
2531 		nat_t *next;
2532 		nat_t *nat;
2533 
2534 		for (next = softn->ipf_nat_instances; (nat = next) != NULL;) {
2535 			next = nat->nat_next;
2536 			if (nat->nat_ptr == np)
2537 				ipf_nat_delete(softc, nat, NL_PURGE);
2538 		}
2539 	}
2540 
2541 	if ((np->in_flags & IPN_DELETE) == 0) {
2542 		if (np->in_redir & NAT_REDIRECT) {
2543 			switch (np->in_v[0])
2544 			{
2545 			case 4 :
2546 				ipf_nat_delrdr(softn, np);
2547 				break;
2548 #ifdef USE_INET6
2549 			case 6 :
2550 				ipf_nat6_delrdr(softn, np);
2551 				break;
2552 #endif
2553 			}
2554 		}
2555 		if (np->in_redir & (NAT_MAPBLK|NAT_MAP)) {
2556 			switch (np->in_v[0])
2557 			{
2558 			case 4 :
2559 				ipf_nat_delmap(softn, np);
2560 				break;
2561 #ifdef USE_INET6
2562 			case 6 :
2563 				ipf_nat6_delmap(softn, np);
2564 				break;
2565 #endif
2566 			}
2567 		}
2568 	}
2569 
2570 	np->in_flags |= IPN_DELETE;
2571 	ipf_nat_rule_deref(softc, &np);
2572 }
2573 
2574 
2575 /* ------------------------------------------------------------------------ */
2576 /* Function:    ipf_nat_newmap                                              */
2577 /* Returns:     int - -1 == error, 0 == success                             */
2578 /* Parameters:  fin(I) - pointer to packet information                      */
2579 /*              nat(I) - pointer to NAT entry                               */
2580 /*              ni(I)  - pointer to structure with misc. information needed */
2581 /*                       to create new NAT entry.                           */
2582 /*                                                                          */
2583 /* Given an empty NAT structure, populate it with new information about a   */
2584 /* new NAT session, as defined by the matching NAT rule.                    */
2585 /* ni.nai_ip is passed in uninitialised and must be set, in host byte order,*/
2586 /* to the new IP address for the translation.                               */
2587 /* ------------------------------------------------------------------------ */
2588 static int
ipf_nat_newmap(fr_info_t * fin,nat_t * nat,natinfo_t * ni)2589 ipf_nat_newmap(fr_info_t *fin, nat_t *nat, natinfo_t *ni)
2590 {
2591 	ipf_main_softc_t *softc = fin->fin_main_soft;
2592 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
2593 	u_short st_port, dport, sport, port, sp, dp;
2594 	struct in_addr in, inb;
2595 	hostmap_t *hm;
2596 	u_32_t flags;
2597 	u_32_t st_ip;
2598 	ipnat_t *np;
2599 	nat_t *natl;
2600 	int l;
2601 
2602 	/*
2603 	 * If it's an outbound packet which doesn't match any existing
2604 	 * record, then create a new port
2605 	 */
2606 	l = 0;
2607 	hm = NULL;
2608 	np = ni->nai_np;
2609 	st_ip = np->in_snip;
2610 	st_port = np->in_spnext;
2611 	flags = nat->nat_flags;
2612 
2613 	if (flags & IPN_ICMPQUERY) {
2614 		sport = fin->fin_data[1];
2615 		dport = 0;
2616 	} else {
2617 		sport = htons(fin->fin_data[0]);
2618 		dport = htons(fin->fin_data[1]);
2619 	}
2620 
2621 	/*
2622 	 * Do a loop until we either run out of entries to try or we find
2623 	 * a NAT mapping that isn't currently being used.  This is done
2624 	 * because the change to the source is not (usually) being fixed.
2625 	 */
2626 	do {
2627 		port = 0;
2628 		in.s_addr = htonl(np->in_snip);
2629 		if (l == 0) {
2630 			/*
2631 			 * Check to see if there is an existing NAT
2632 			 * setup for this IP address pair.
2633 			 */
2634 			hm = ipf_nat_hostmap(softn, np, fin->fin_src,
2635 					     fin->fin_dst, in, 0);
2636 			if (hm != NULL)
2637 				in.s_addr = hm->hm_nsrcip.s_addr;
2638 		} else if ((l == 1) && (hm != NULL)) {
2639 			ipf_nat_hostmapdel(softc, &hm);
2640 		}
2641 		in.s_addr = ntohl(in.s_addr);
2642 
2643 		nat->nat_hm = hm;
2644 
2645 		if ((np->in_nsrcmsk == 0xffffffff) && (np->in_spnext == 0)) {
2646 			if (l > 0) {
2647 				NBUMPSIDEX(1, ns_exhausted, ns_exhausted_1);
2648 				return -1;
2649 			}
2650 		}
2651 
2652 		if (np->in_redir == NAT_BIMAP &&
2653 		    np->in_osrcmsk == np->in_nsrcmsk) {
2654 			/*
2655 			 * map the address block in a 1:1 fashion
2656 			 */
2657 			in.s_addr = np->in_nsrcaddr;
2658 			in.s_addr |= fin->fin_saddr & ~np->in_osrcmsk;
2659 			in.s_addr = ntohl(in.s_addr);
2660 
2661 		} else if (np->in_redir & NAT_MAPBLK) {
2662 			if ((l >= np->in_ppip) || ((l > 0) &&
2663 			     !(flags & IPN_TCPUDP))) {
2664 				NBUMPSIDEX(1, ns_exhausted, ns_exhausted_2);
2665 				return -1;
2666 			}
2667 			/*
2668 			 * map-block - Calculate destination address.
2669 			 */
2670 			in.s_addr = ntohl(fin->fin_saddr);
2671 			in.s_addr &= ntohl(~np->in_osrcmsk);
2672 			inb.s_addr = in.s_addr;
2673 			in.s_addr /= np->in_ippip;
2674 			in.s_addr &= ntohl(~np->in_nsrcmsk);
2675 			in.s_addr += ntohl(np->in_nsrcaddr);
2676 			/*
2677 			 * Calculate destination port.
2678 			 */
2679 			if ((flags & IPN_TCPUDP) &&
2680 			    (np->in_ppip != 0)) {
2681 				port = ntohs(sport) + l;
2682 				port %= np->in_ppip;
2683 				port += np->in_ppip *
2684 					(inb.s_addr % np->in_ippip);
2685 				port += MAPBLK_MINPORT;
2686 				port = htons(port);
2687 			}
2688 
2689 		} else if ((np->in_nsrcaddr == 0) &&
2690 			   (np->in_nsrcmsk == 0xffffffff)) {
2691 			i6addr_t in6;
2692 
2693 			/*
2694 			 * 0/32 - use the interface's IP address.
2695 			 */
2696 			if ((l > 0) ||
2697 			    ipf_ifpaddr(softc, 4, FRI_NORMAL, fin->fin_ifp,
2698 				       &in6, NULL) == -1) {
2699 				NBUMPSIDEX(1, ns_new_ifpaddr, ns_new_ifpaddr_1);
2700 				return -1;
2701 			}
2702 			in.s_addr = ntohl(in6.in4.s_addr);
2703 
2704 		} else if ((np->in_nsrcaddr == 0) && (np->in_nsrcmsk == 0)) {
2705 			/*
2706 			 * 0/0 - use the original source address/port.
2707 			 */
2708 			if (l > 0) {
2709 				NBUMPSIDEX(1, ns_exhausted, ns_exhausted_3);
2710 				return -1;
2711 			}
2712 			in.s_addr = ntohl(fin->fin_saddr);
2713 
2714 		} else if ((np->in_nsrcmsk != 0xffffffff) &&
2715 			   (np->in_spnext == 0) && ((l > 0) || (hm == NULL)))
2716 			np->in_snip++;
2717 
2718 		natl = NULL;
2719 
2720 		if ((flags & IPN_TCPUDP) &&
2721 		    ((np->in_redir & NAT_MAPBLK) == 0) &&
2722 		    (np->in_flags & IPN_AUTOPORTMAP)) {
2723 			/*
2724 			 * "ports auto" (without map-block)
2725 			 */
2726 			if ((l > 0) && np->in_ppip && (l % np->in_ppip == 0)) {
2727 				if (l > np->in_space) {
2728 					return -1;
2729 				} else if ((l > np->in_ppip) &&
2730 					   np->in_nsrcmsk != 0xffffffff)
2731 					np->in_snip++;
2732 			}
2733 			if (np->in_ppip != 0) {
2734 				port = ntohs(sport);
2735 				port += (l % np->in_ppip);
2736 				port %= np->in_ppip;
2737 				port += np->in_ppip *
2738 					(ntohl(fin->fin_saddr) %
2739 					 np->in_ippip);
2740 				port += MAPBLK_MINPORT;
2741 				port = htons(port);
2742 			}
2743 
2744 		} else if (((np->in_redir & NAT_MAPBLK) == 0) &&
2745 			   (flags & IPN_TCPUDPICMP) && (np->in_spnext != 0)) {
2746 			/*
2747 			 * Standard port translation.  Select next port.
2748 			 */
2749 			if (np->in_flags & IPN_SEQUENTIAL) {
2750 				port = np->in_spnext;
2751 			} else {
2752 				port = ipf_random() % (np->in_spmax -
2753 						       np->in_spmin + 1);
2754 				port += np->in_spmin;
2755 			}
2756 			port = htons(port);
2757 			np->in_spnext++;
2758 
2759 			if (np->in_spnext > np->in_spmax) {
2760 				np->in_spnext = np->in_spmin;
2761 				if (np->in_nsrcmsk != 0xffffffff)
2762 					np->in_snip++;
2763 			}
2764 		}
2765 
2766 		if (np->in_flags & IPN_SIPRANGE) {
2767 			if (np->in_snip > ntohl(np->in_nsrcmsk))
2768 				np->in_snip = ntohl(np->in_nsrcaddr);
2769 		} else {
2770 			if ((np->in_nsrcmsk != 0xffffffff) &&
2771 			    ((np->in_snip + 1) & ntohl(np->in_nsrcmsk)) >
2772 			    ntohl(np->in_nsrcaddr))
2773 				np->in_snip = ntohl(np->in_nsrcaddr) + 1;
2774 		}
2775 
2776 		if ((port == 0) && (flags & (IPN_TCPUDPICMP|IPN_ICMPQUERY)))
2777 			port = sport;
2778 
2779 		/*
2780 		 * Here we do a lookup of the connection as seen from
2781 		 * the outside.  If an IP# pair already exists, try
2782 		 * again.  So if you have A->B becomes C->B, you can
2783 		 * also have D->E become C->E but not D->B causing
2784 		 * another C->B.  Also take protocol and ports into
2785 		 * account when determining whether a pre-existing
2786 		 * NAT setup will cause an external conflict where
2787 		 * this is appropriate.
2788 		 */
2789 		inb.s_addr = htonl(in.s_addr);
2790 		sp = fin->fin_data[0];
2791 		dp = fin->fin_data[1];
2792 		fin->fin_data[0] = fin->fin_data[1];
2793 		fin->fin_data[1] = ntohs(port);
2794 		natl = ipf_nat_inlookup(fin, flags & ~(SI_WILDP|NAT_SEARCH),
2795 					(u_int)fin->fin_p, fin->fin_dst, inb);
2796 		fin->fin_data[0] = sp;
2797 		fin->fin_data[1] = dp;
2798 
2799 		/*
2800 		 * Has the search wrapped around and come back to the
2801 		 * start ?
2802 		 */
2803 		if ((natl != NULL) &&
2804 		    (np->in_spnext != 0) && (st_port == np->in_spnext) &&
2805 		    (np->in_snip != 0) && (st_ip == np->in_snip)) {
2806 			NBUMPSIDED(1, ns_wrap);
2807 			return -1;
2808 		}
2809 		l++;
2810 	} while (natl != NULL);
2811 
2812 	/* Setup the NAT table */
2813 	nat->nat_osrcip = fin->fin_src;
2814 	nat->nat_nsrcaddr = htonl(in.s_addr);
2815 	nat->nat_odstip = fin->fin_dst;
2816 	nat->nat_ndstip = fin->fin_dst;
2817 	if (nat->nat_hm == NULL)
2818 		nat->nat_hm = ipf_nat_hostmap(softn, np, fin->fin_src,
2819 					      fin->fin_dst, nat->nat_nsrcip,
2820 					      0);
2821 
2822 	if (flags & IPN_TCPUDP) {
2823 		nat->nat_osport = sport;
2824 		nat->nat_nsport = port;	/* sport */
2825 		nat->nat_odport = dport;
2826 		nat->nat_ndport = dport;
2827 		((tcphdr_t *)fin->fin_dp)->th_sport = port;
2828 	} else if (flags & IPN_ICMPQUERY) {
2829 		nat->nat_oicmpid = fin->fin_data[1];
2830 		((icmphdr_t *)fin->fin_dp)->icmp_id = port;
2831 		nat->nat_nicmpid = port;
2832 	}
2833 	return 0;
2834 }
2835 
2836 
2837 /* ------------------------------------------------------------------------ */
2838 /* Function:    ipf_nat_newrdr                                              */
2839 /* Returns:     int - -1 == error, 0 == success (no move), 1 == success and */
2840 /*                    allow rule to be moved if IPN_ROUNDR is set.          */
2841 /* Parameters:  fin(I) - pointer to packet information                      */
2842 /*              nat(I) - pointer to NAT entry                               */
2843 /*              ni(I)  - pointer to structure with misc. information needed */
2844 /*                       to create new NAT entry.                           */
2845 /*                                                                          */
2846 /* ni.nai_ip is passed in uninitialised and must be set, in host byte order,*/
2847 /* to the new IP address for the translation.                               */
2848 /* ------------------------------------------------------------------------ */
2849 static int
ipf_nat_newrdr(fr_info_t * fin,nat_t * nat,natinfo_t * ni)2850 ipf_nat_newrdr(fr_info_t *fin, nat_t *nat, natinfo_t *ni)
2851 {
2852 	ipf_main_softc_t *softc = fin->fin_main_soft;
2853 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
2854 	u_short nport, dport, sport;
2855 	struct in_addr in, inb;
2856 	u_short sp, dp;
2857 	hostmap_t *hm;
2858 	u_32_t flags;
2859 	ipnat_t *np;
2860 	nat_t *natl;
2861 	int move;
2862 
2863 	move = 1;
2864 	hm = NULL;
2865 	in.s_addr = 0;
2866 	np = ni->nai_np;
2867 	flags = nat->nat_flags;
2868 
2869 	if (flags & IPN_ICMPQUERY) {
2870 		dport = fin->fin_data[1];
2871 		sport = 0;
2872 	} else {
2873 		sport = htons(fin->fin_data[0]);
2874 		dport = htons(fin->fin_data[1]);
2875 	}
2876 
2877 	/* TRACE sport, dport */
2878 
2879 
2880 	/*
2881 	 * If the matching rule has IPN_STICKY set, then we want to have the
2882 	 * same rule kick in as before.  Why would this happen?  If you have
2883 	 * a collection of rdr rules with "round-robin sticky", the current
2884 	 * packet might match a different one to the previous connection but
2885 	 * we want the same destination to be used.
2886 	 */
2887 	if (((np->in_flags & (IPN_ROUNDR|IPN_SPLIT)) != 0) &&
2888 	    ((np->in_flags & IPN_STICKY) != 0)) {
2889 		hm = ipf_nat_hostmap(softn, NULL, fin->fin_src, fin->fin_dst,
2890 				     in, (u_32_t)dport);
2891 		if (hm != NULL) {
2892 			in.s_addr = ntohl(hm->hm_ndstip.s_addr);
2893 			np = hm->hm_ipnat;
2894 			ni->nai_np = np;
2895 			move = 0;
2896 			ipf_nat_hostmapdel(softc, &hm);
2897 		}
2898 	}
2899 
2900 	/*
2901 	 * Otherwise, it's an inbound packet. Most likely, we don't
2902 	 * want to rewrite source ports and source addresses. Instead,
2903 	 * we want to rewrite to a fixed internal address and fixed
2904 	 * internal port.
2905 	 */
2906 	if (np->in_flags & IPN_SPLIT) {
2907 		in.s_addr = np->in_dnip;
2908 		inb.s_addr = htonl(in.s_addr);
2909 
2910 		if ((np->in_flags & (IPN_ROUNDR|IPN_STICKY)) == IPN_STICKY) {
2911 			hm = ipf_nat_hostmap(softn, NULL, fin->fin_src,
2912 					     fin->fin_dst, inb, (u_32_t)dport);
2913 			if (hm != NULL) {
2914 				in.s_addr = hm->hm_ndstip.s_addr;
2915 				move = 0;
2916 			}
2917 		}
2918 
2919 		if (hm == NULL || hm->hm_ref == 1) {
2920 			if (np->in_ndstaddr == htonl(in.s_addr)) {
2921 				np->in_dnip = ntohl(np->in_ndstmsk);
2922 				move = 0;
2923 			} else {
2924 				np->in_dnip = ntohl(np->in_ndstaddr);
2925 			}
2926 		}
2927 		if (hm != NULL)
2928 			ipf_nat_hostmapdel(softc, &hm);
2929 
2930 	} else if ((np->in_ndstaddr == 0) && (np->in_ndstmsk == 0xffffffff)) {
2931 		i6addr_t in6;
2932 
2933 		/*
2934 		 * 0/32 - use the interface's IP address.
2935 		 */
2936 		if (ipf_ifpaddr(softc, 4, FRI_NORMAL, fin->fin_ifp,
2937 			       &in6, NULL) == -1) {
2938 			NBUMPSIDEX(0, ns_new_ifpaddr, ns_new_ifpaddr_2);
2939 			return -1;
2940 		}
2941 		in.s_addr = ntohl(in6.in4.s_addr);
2942 
2943 	} else if ((np->in_ndstaddr == 0) && (np->in_ndstmsk== 0)) {
2944 		/*
2945 		 * 0/0 - use the original destination address/port.
2946 		 */
2947 		in.s_addr = ntohl(fin->fin_daddr);
2948 
2949 	} else if (np->in_redir == NAT_BIMAP &&
2950 		   np->in_ndstmsk == np->in_odstmsk) {
2951 		/*
2952 		 * map the address block in a 1:1 fashion
2953 		 */
2954 		in.s_addr = np->in_ndstaddr;
2955 		in.s_addr |= fin->fin_daddr & ~np->in_ndstmsk;
2956 		in.s_addr = ntohl(in.s_addr);
2957 	} else {
2958 		in.s_addr = ntohl(np->in_ndstaddr);
2959 	}
2960 
2961 	if ((np->in_dpnext == 0) || ((flags & NAT_NOTRULEPORT) != 0))
2962 		nport = dport;
2963 	else {
2964 		/*
2965 		 * Whilst not optimized for the case where
2966 		 * pmin == pmax, the gain is not significant.
2967 		 */
2968 		if (((np->in_flags & IPN_FIXEDDPORT) == 0) &&
2969 		    (np->in_odport != np->in_dtop)) {
2970 			nport = ntohs(dport) - np->in_odport + np->in_dpmax;
2971 			nport = htons(nport);
2972 		} else {
2973 			nport = htons(np->in_dpnext);
2974 			np->in_dpnext++;
2975 			if (np->in_dpnext > np->in_dpmax)
2976 				np->in_dpnext = np->in_dpmin;
2977 		}
2978 	}
2979 
2980 	/*
2981 	 * When the redirect-to address is set to 0.0.0.0, just
2982 	 * assume a blank `forwarding' of the packet.  We don't
2983 	 * setup any translation for this either.
2984 	 */
2985 	if (in.s_addr == 0) {
2986 		if (nport == dport) {
2987 			NBUMPSIDED(0, ns_xlate_null);
2988 			return -1;
2989 		}
2990 		in.s_addr = ntohl(fin->fin_daddr);
2991 	}
2992 
2993 	/*
2994 	 * Check to see if this redirect mapping already exists and if
2995 	 * it does, return "failure" (allowing it to be created will just
2996 	 * cause one or both of these "connections" to stop working.)
2997 	 */
2998 	inb.s_addr = htonl(in.s_addr);
2999 	sp = fin->fin_data[0];
3000 	dp = fin->fin_data[1];
3001 	fin->fin_data[1] = fin->fin_data[0];
3002 	fin->fin_data[0] = ntohs(nport);
3003 	natl = ipf_nat_outlookup(fin, flags & ~(SI_WILDP|NAT_SEARCH),
3004 			     (u_int)fin->fin_p, inb, fin->fin_src);
3005 	fin->fin_data[0] = sp;
3006 	fin->fin_data[1] = dp;
3007 	if (natl != NULL) {
3008 		DT2(ns_new_xlate_exists, fr_info_t *, fin, nat_t *, natl);
3009 		NBUMPSIDE(0, ns_xlate_exists);
3010 		return -1;
3011 	}
3012 
3013 	nat->nat_ndstaddr = htonl(in.s_addr);
3014 	nat->nat_odstip = fin->fin_dst;
3015 	nat->nat_nsrcip = fin->fin_src;
3016 	nat->nat_osrcip = fin->fin_src;
3017 	if ((nat->nat_hm == NULL) && ((np->in_flags & IPN_STICKY) != 0))
3018 		nat->nat_hm = ipf_nat_hostmap(softn, np, fin->fin_src,
3019 					      fin->fin_dst, inb, (u_32_t)dport);
3020 
3021 	if (flags & IPN_TCPUDP) {
3022 		nat->nat_odport = dport;
3023 		nat->nat_ndport = nport;
3024 		nat->nat_osport = sport;
3025 		nat->nat_nsport = sport;
3026 		((tcphdr_t *)fin->fin_dp)->th_dport = nport;
3027 	} else if (flags & IPN_ICMPQUERY) {
3028 		nat->nat_oicmpid = fin->fin_data[1];
3029 		((icmphdr_t *)fin->fin_dp)->icmp_id = nport;
3030 		nat->nat_nicmpid = nport;
3031 	}
3032 
3033 	return move;
3034 }
3035 
3036 /* ------------------------------------------------------------------------ */
3037 /* Function:    ipf_nat_add                                                 */
3038 /* Returns:     nat_t* - NULL == failure to create new NAT structure,       */
3039 /*                       else pointer to new NAT structure                  */
3040 /* Parameters:  fin(I)       - pointer to packet information                */
3041 /*              np(I)        - pointer to NAT rule                          */
3042 /*              natsave(I)   - pointer to where to store NAT struct pointer */
3043 /*              flags(I)     - flags describing the current packet          */
3044 /*              direction(I) - direction of packet (in/out)                 */
3045 /* Write Lock:  ipf_nat                                                     */
3046 /*                                                                          */
3047 /* Attempts to create a new NAT entry.  Does not actually change the packet */
3048 /* in any way.                                                              */
3049 /*                                                                          */
3050 /* This function is in three main parts: (1) deal with creating a new NAT   */
3051 /* structure for a "MAP" rule (outgoing NAT translation); (2) deal with     */
3052 /* creating a new NAT structure for a "RDR" rule (incoming NAT translation) */
3053 /* and (3) building that structure and putting it into the NAT table(s).    */
3054 /*                                                                          */
3055 /* NOTE: natsave should NOT be used to point back to an ipstate_t struct    */
3056 /*       as it can result in memory being corrupted.                        */
3057 /* ------------------------------------------------------------------------ */
3058 nat_t *
ipf_nat_add(fr_info_t * fin,ipnat_t * np,nat_t ** natsave,u_int flags,int direction)3059 ipf_nat_add(fr_info_t *fin, ipnat_t *np, nat_t **natsave, u_int flags,
3060     int direction)
3061 {
3062 	ipf_main_softc_t *softc = fin->fin_main_soft;
3063 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
3064 	hostmap_t *hm = NULL;
3065 	nat_t *nat, *natl;
3066 	natstat_t *nsp;
3067 	u_int nflags;
3068 	natinfo_t ni;
3069 	int move;
3070 
3071 	memset(&ni, 0, sizeof ni);	/* XXX gcc */
3072 	nsp = &softn->ipf_nat_stats;
3073 
3074 	if ((nsp->ns_active * 100 / softn->ipf_nat_table_max) >
3075 	    softn->ipf_nat_table_wm_high) {
3076 		softn->ipf_nat_doflush = 1;
3077 	}
3078 
3079 	if (nsp->ns_active >= softn->ipf_nat_table_max) {
3080 		NBUMPSIDED(fin->fin_out, ns_table_max);
3081 		return NULL;
3082 	}
3083 
3084 	move = 1;
3085 	nflags = np->in_flags & flags;
3086 	nflags &= NAT_FROMRULE;
3087 
3088 	ni.nai_np = np;
3089 	ni.nai_dport = 0;
3090 	ni.nai_sport = 0;
3091 
3092 	/* Give me a new nat */
3093 	KMALLOC(nat, nat_t *);
3094 	if (nat == NULL) {
3095 		NBUMPSIDED(fin->fin_out, ns_memfail);
3096 		/*
3097 		 * Try to automatically tune the max # of entries in the
3098 		 * table allowed to be less than what will cause kmem_alloc()
3099 		 * to fail and try to eliminate panics due to out of memory
3100 		 * conditions arising.
3101 		 */
3102 		if ((softn->ipf_nat_table_max > softn->ipf_nat_table_sz) &&
3103 		    (nsp->ns_active > 100)) {
3104 			softn->ipf_nat_table_max = nsp->ns_active - 100;
3105 			printf("table_max reduced to %d\n",
3106 				softn->ipf_nat_table_max);
3107 		}
3108 		return NULL;
3109 	}
3110 
3111 	if (flags & IPN_ICMPQUERY) {
3112 		/*
3113 		 * In the ICMP query NAT code, we translate the ICMP id fields
3114 		 * to make them unique. This is indepedent of the ICMP type
3115 		 * (e.g. in the unlikely event that a host sends an echo and
3116 		 * an tstamp request with the same id, both packets will have
3117 		 * their ip address/id field changed in the same way).
3118 		 */
3119 		/* The icmp_id field is used by the sender to identify the
3120 		 * process making the icmp request. (the receiver justs
3121 		 * copies it back in its response). So, it closely matches
3122 		 * the concept of source port. We overlay sport, so we can
3123 		 * maximally reuse the existing code.
3124 		 */
3125 		ni.nai_sport = fin->fin_data[1];
3126 		ni.nai_dport = 0;
3127 	}
3128 
3129 	bzero((char *)nat, sizeof(*nat));
3130 	nat->nat_flags = flags;
3131 	nat->nat_redir = np->in_redir;
3132 	nat->nat_dir = direction;
3133 	nat->nat_pr[0] = fin->fin_p;
3134 	nat->nat_pr[1] = fin->fin_p;
3135 
3136 	/*
3137 	 * Search the current table for a match and create a new mapping
3138 	 * if there is none found.
3139 	 */
3140 	if (np->in_redir & NAT_DIVERTUDP) {
3141 		move = ipf_nat_newdivert(fin, nat, &ni);
3142 
3143 	} else if (np->in_redir & NAT_REWRITE) {
3144 		move = ipf_nat_newrewrite(fin, nat, &ni);
3145 
3146 	} else if (direction == NAT_OUTBOUND) {
3147 		/*
3148 		 * We can now arrange to call this for the same connection
3149 		 * because ipf_nat_new doesn't protect the code path into
3150 		 * this function.
3151 		 */
3152 		natl = ipf_nat_outlookup(fin, nflags, (u_int)fin->fin_p,
3153 				     fin->fin_src, fin->fin_dst);
3154 		if (natl != NULL) {
3155 			KFREE(nat);
3156 			nat = natl;
3157 			goto done;
3158 		}
3159 
3160 		move = ipf_nat_newmap(fin, nat, &ni);
3161 	} else {
3162 		/*
3163 		 * NAT_INBOUND is used for redirects rules
3164 		 */
3165 		natl = ipf_nat_inlookup(fin, nflags, (u_int)fin->fin_p,
3166 					fin->fin_src, fin->fin_dst);
3167 		if (natl != NULL) {
3168 			KFREE(nat);
3169 			nat = natl;
3170 			goto done;
3171 		}
3172 
3173 		move = ipf_nat_newrdr(fin, nat, &ni);
3174 	}
3175 	if (move == -1)
3176 		goto badnat;
3177 
3178 	np = ni.nai_np;
3179 
3180 	nat->nat_mssclamp = np->in_mssclamp;
3181 	nat->nat_me = natsave;
3182 	nat->nat_fr = fin->fin_fr;
3183 	nat->nat_rev = fin->fin_rev;
3184 	nat->nat_ptr = np;
3185 	nat->nat_dlocal = np->in_dlocal;
3186 
3187 	if ((np->in_apr != NULL) && ((nat->nat_flags & NAT_SLAVE) == 0)) {
3188 		if (ipf_proxy_new(fin, nat) == -1) {
3189 			NBUMPSIDED(fin->fin_out, ns_appr_fail);
3190 			goto badnat;
3191 		}
3192 	}
3193 
3194 	nat->nat_ifps[0] = np->in_ifps[0];
3195 	if (np->in_ifps[0] != NULL) {
3196 		COPYIFNAME(np->in_v[0], np->in_ifps[0], nat->nat_ifnames[0]);
3197 	}
3198 
3199 	nat->nat_ifps[1] = np->in_ifps[1];
3200 	if (np->in_ifps[1] != NULL) {
3201 		COPYIFNAME(np->in_v[1], np->in_ifps[1], nat->nat_ifnames[1]);
3202 	}
3203 
3204 	if (ipf_nat_finalise(fin, nat) == -1) {
3205 		goto badnat;
3206 	}
3207 
3208 	np->in_use++;
3209 
3210 	if ((move == 1) && (np->in_flags & IPN_ROUNDR)) {
3211 		if ((np->in_redir & (NAT_REDIRECT|NAT_MAP)) == NAT_REDIRECT) {
3212 			ipf_nat_delrdr(softn, np);
3213 			ipf_nat_addrdr(softn, np);
3214 		} else if ((np->in_redir & (NAT_REDIRECT|NAT_MAP)) == NAT_MAP) {
3215 			ipf_nat_delmap(softn, np);
3216 			ipf_nat_addmap(softn, np);
3217 		}
3218 	}
3219 
3220 	if (flags & SI_WILDP)
3221 		nsp->ns_wilds++;
3222 	nsp->ns_proto[nat->nat_pr[0]]++;
3223 
3224 	goto done;
3225 badnat:
3226 	DT2(ns_badnatnew, fr_info_t *, fin, nat_t *, nat);
3227 	NBUMPSIDE(fin->fin_out, ns_badnatnew);
3228 	if ((hm = nat->nat_hm) != NULL)
3229 		ipf_nat_hostmapdel(softc, &hm);
3230 	KFREE(nat);
3231 	nat = NULL;
3232 done:
3233 	if (nat != NULL && np != NULL)
3234 		np->in_hits++;
3235 	if (natsave != NULL)
3236 		*natsave = nat;
3237 	return nat;
3238 }
3239 
3240 
3241 /* ------------------------------------------------------------------------ */
3242 /* Function:    ipf_nat_finalise                                            */
3243 /* Returns:     int - 0 == sucess, -1 == failure                            */
3244 /* Parameters:  fin(I) - pointer to packet information                      */
3245 /*              nat(I) - pointer to NAT entry                               */
3246 /* Write Lock:  ipf_nat                                                     */
3247 /*                                                                          */
3248 /* This is the tail end of constructing a new NAT entry and is the same     */
3249 /* for both IPv4 and IPv6.                                                  */
3250 /* ------------------------------------------------------------------------ */
3251 /*ARGSUSED*/
3252 static int
ipf_nat_finalise(fr_info_t * fin,nat_t * nat)3253 ipf_nat_finalise(fr_info_t *fin, nat_t *nat)
3254 {
3255 	ipf_main_softc_t *softc = fin->fin_main_soft;
3256 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
3257 	u_32_t sum1, sum2, sumd;
3258 	frentry_t *fr;
3259 #if SOLARIS && defined(_KERNEL) && (SOLARIS2 >= 6) && defined(ICK_M_CTL_MAGIC)
3260 	qpktinfo_t *qpi = fin->fin_qpi;
3261 #endif
3262 
3263 	switch (nat->nat_pr[0])
3264 	{
3265 	case IPPROTO_ICMP :
3266 		sum1 = LONG_SUM(ntohs(nat->nat_oicmpid));
3267 		sum2 = LONG_SUM(ntohs(nat->nat_nicmpid));
3268 		CALC_SUMD(sum1, sum2, sumd);
3269 		nat->nat_sumd[0] = (sumd & 0xffff) + (sumd >> 16);
3270 
3271 		break;
3272 
3273 	default :
3274 		sum1 = LONG_SUM(ntohl(nat->nat_osrcaddr) + \
3275 				ntohs(nat->nat_osport));
3276 		sum2 = LONG_SUM(ntohl(nat->nat_nsrcaddr) + \
3277 				ntohs(nat->nat_nsport));
3278 		CALC_SUMD(sum1, sum2, sumd);
3279 		nat->nat_sumd[0] = (sumd & 0xffff) + (sumd >> 16);
3280 
3281 		sum1 = LONG_SUM(ntohl(nat->nat_odstaddr) + \
3282 				ntohs(nat->nat_odport));
3283 		sum2 = LONG_SUM(ntohl(nat->nat_ndstaddr) + \
3284 				ntohs(nat->nat_ndport));
3285 		CALC_SUMD(sum1, sum2, sumd);
3286 		nat->nat_sumd[0] += (sumd & 0xffff) + (sumd >> 16);
3287 		break;
3288 	}
3289 
3290 	/*
3291 	 * Compute the partial checksum, just in case.
3292 	 * This is only ever placed into outbound packets so care needs
3293 	 * to be taken over which pair of addresses are used.
3294 	 */
3295 	if (nat->nat_dir == NAT_OUTBOUND) {
3296 		sum1 = LONG_SUM(ntohl(nat->nat_nsrcaddr));
3297 		sum1 += LONG_SUM(ntohl(nat->nat_ndstaddr));
3298 	} else {
3299 		sum1 = LONG_SUM(ntohl(nat->nat_osrcaddr));
3300 		sum1 += LONG_SUM(ntohl(nat->nat_odstaddr));
3301 	}
3302 	sum1 += nat->nat_pr[1];
3303 	nat->nat_sumd[1] = (sum1 & 0xffff) + (sum1 >> 16);
3304 
3305 	sum1 = LONG_SUM(ntohl(nat->nat_osrcaddr));
3306 	sum2 = LONG_SUM(ntohl(nat->nat_nsrcaddr));
3307 	CALC_SUMD(sum1, sum2, sumd);
3308 	nat->nat_ipsumd = (sumd & 0xffff) + (sumd >> 16);
3309 
3310 	sum1 = LONG_SUM(ntohl(nat->nat_odstaddr));
3311 	sum2 = LONG_SUM(ntohl(nat->nat_ndstaddr));
3312 	CALC_SUMD(sum1, sum2, sumd);
3313 	nat->nat_ipsumd += (sumd & 0xffff) + (sumd >> 16);
3314 
3315 	nat->nat_v[0] = 4;
3316 	nat->nat_v[1] = 4;
3317 
3318 	if ((nat->nat_ifps[0] != NULL) && (nat->nat_ifps[0] != (void *)-1)) {
3319 		nat->nat_mtu[0] = GETIFMTU_4(nat->nat_ifps[0]);
3320 	}
3321 
3322 	if ((nat->nat_ifps[1] != NULL) && (nat->nat_ifps[1] != (void *)-1)) {
3323 		nat->nat_mtu[1] = GETIFMTU_4(nat->nat_ifps[1]);
3324 	}
3325 
3326 	if ((nat->nat_flags & SI_CLONE) == 0)
3327 		nat->nat_sync = ipf_sync_new(softc, SMC_NAT, fin, nat);
3328 
3329 	if (ipf_nat_insert(softc, softn, nat) == 0) {
3330 		if (softn->ipf_nat_logging)
3331 			ipf_nat_log(softc, softn, nat, NL_NEW);
3332 		fr = nat->nat_fr;
3333 		if (fr != NULL) {
3334 			MUTEX_ENTER(&fr->fr_lock);
3335 			fr->fr_ref++;
3336 			MUTEX_EXIT(&fr->fr_lock);
3337 		}
3338 		return 0;
3339 	}
3340 
3341 	NBUMPSIDED(fin->fin_out, ns_unfinalised);
3342 	/*
3343 	 * nat_insert failed, so cleanup time...
3344 	 */
3345 	if (nat->nat_sync != NULL)
3346 		ipf_sync_del_nat(softc->ipf_sync_soft, nat->nat_sync);
3347 	return -1;
3348 }
3349 
3350 
3351 /* ------------------------------------------------------------------------ */
3352 /* Function:    ipf_nat_insert                                              */
3353 /* Returns:     int - 0 == sucess, -1 == failure                            */
3354 /* Parameters:  softc(I) - pointer to soft context main structure           */
3355 /*              softn(I) - pointer to NAT context structure                 */
3356 /*              nat(I) - pointer to NAT structure                           */
3357 /* Write Lock:  ipf_nat                                                     */
3358 /*                                                                          */
3359 /* Insert a NAT entry into the hash tables for searching and add it to the  */
3360 /* list of active NAT entries.  Adjust global counters when complete.       */
3361 /* ------------------------------------------------------------------------ */
3362 int
ipf_nat_insert(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,nat_t * nat)3363 ipf_nat_insert(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, nat_t *nat)
3364 {
3365 	u_int hv0, hv1;
3366 	u_int sp, dp;
3367 	ipnat_t *in;
3368 	int ret;
3369 
3370 	/*
3371 	 * Try and return an error as early as possible, so calculate the hash
3372 	 * entry numbers first and then proceed.
3373 	 */
3374 	if ((nat->nat_flags & (SI_W_SPORT|SI_W_DPORT)) == 0) {
3375 		if ((nat->nat_flags & IPN_TCPUDP) != 0) {
3376 			sp = nat->nat_osport;
3377 			dp = nat->nat_odport;
3378 		} else if ((nat->nat_flags & IPN_ICMPQUERY) != 0) {
3379 			sp = 0;
3380 			dp = nat->nat_oicmpid;
3381 		} else {
3382 			sp = 0;
3383 			dp = 0;
3384 		}
3385 		hv0 = NAT_HASH_FN(nat->nat_osrcaddr, sp, 0xffffffff);
3386 		hv0 = NAT_HASH_FN(nat->nat_odstaddr, hv0 + dp, 0xffffffff);
3387 		/*
3388 		 * TRACE nat_osrcaddr, nat_osport, nat_odstaddr,
3389 		 * nat_odport, hv0
3390 		 */
3391 
3392 		if ((nat->nat_flags & IPN_TCPUDP) != 0) {
3393 			sp = nat->nat_nsport;
3394 			dp = nat->nat_ndport;
3395 		} else if ((nat->nat_flags & IPN_ICMPQUERY) != 0) {
3396 			sp = 0;
3397 			dp = nat->nat_nicmpid;
3398 		} else {
3399 			sp = 0;
3400 			dp = 0;
3401 		}
3402 		hv1 = NAT_HASH_FN(nat->nat_nsrcaddr, sp, 0xffffffff);
3403 		hv1 = NAT_HASH_FN(nat->nat_ndstaddr, hv1 + dp, 0xffffffff);
3404 		/*
3405 		 * TRACE nat_nsrcaddr, nat_nsport, nat_ndstaddr,
3406 		 * nat_ndport, hv1
3407 		 */
3408 	} else {
3409 		hv0 = NAT_HASH_FN(nat->nat_osrcaddr, 0, 0xffffffff);
3410 		hv0 = NAT_HASH_FN(nat->nat_odstaddr, hv0, 0xffffffff);
3411 		/* TRACE nat_osrcaddr, nat_odstaddr, hv0 */
3412 
3413 		hv1 = NAT_HASH_FN(nat->nat_nsrcaddr, 0, 0xffffffff);
3414 		hv1 = NAT_HASH_FN(nat->nat_ndstaddr, hv1, 0xffffffff);
3415 		/* TRACE nat_nsrcaddr, nat_ndstaddr, hv1 */
3416 	}
3417 
3418 	if ((nat->nat_dir & NAT_OUTBOUND) == NAT_OUTBOUND) {
3419 		nat->nat_hv[0] = hv0;
3420 		nat->nat_hv[1] = hv1;
3421 	} else {
3422 		nat->nat_hv[0] = hv1;
3423 		nat->nat_hv[1] = hv0;
3424 	}
3425 
3426 	MUTEX_INIT(&nat->nat_lock, "nat entry lock");
3427 
3428 	in = nat->nat_ptr;
3429 	nat->nat_ref = nat->nat_me ? 2 : 1;
3430 
3431 	nat->nat_ifnames[0][LIFNAMSIZ - 1] = '\0';
3432 	nat->nat_ifps[0] = ipf_resolvenic(softc, nat->nat_ifnames[0], 4);
3433 
3434 	if (nat->nat_ifnames[1][0] != '\0') {
3435 		nat->nat_ifnames[1][LIFNAMSIZ - 1] = '\0';
3436 		nat->nat_ifps[1] = ipf_resolvenic(softc,
3437 						  nat->nat_ifnames[1], 4);
3438 	} else if (in->in_ifnames[1] != -1) {
3439 		char *name;
3440 
3441 		name = in->in_names + in->in_ifnames[1];
3442 		if (name[1] != '\0' && name[0] != '-' && name[0] != '*') {
3443 			(void) strncpy(nat->nat_ifnames[1],
3444 				       nat->nat_ifnames[0], LIFNAMSIZ);
3445 			nat->nat_ifnames[1][LIFNAMSIZ - 1] = '\0';
3446 			nat->nat_ifps[1] = nat->nat_ifps[0];
3447 		}
3448 	}
3449 	if ((nat->nat_ifps[0] != NULL) && (nat->nat_ifps[0] != (void *)-1)) {
3450 		nat->nat_mtu[0] = GETIFMTU_4(nat->nat_ifps[0]);
3451 	}
3452 	if ((nat->nat_ifps[1] != NULL) && (nat->nat_ifps[1] != (void *)-1)) {
3453 		nat->nat_mtu[1] = GETIFMTU_4(nat->nat_ifps[1]);
3454 	}
3455 
3456 	ret = ipf_nat_hashtab_add(softc, softn, nat);
3457 	if (ret != 0)
3458 		MUTEX_DESTROY(&nat->nat_lock);
3459 	return ret;
3460 }
3461 
3462 
3463 /* ------------------------------------------------------------------------ */
3464 /* Function:    ipf_nat_hashtab_add                                         */
3465 /* Returns:     int - 0 == sucess, -1 == failure                            */
3466 /* Parameters:  softc(I) - pointer to soft context main structure           */
3467 /*              softn(I) - pointer to NAT context structure                 */
3468 /*              nat(I) - pointer to NAT structure                           */
3469 /* Write Lock:  ipf_nat                                                     */
3470 /*                                                                          */
3471 /* Handle the insertion of a NAT entry into the table/list.                 */
3472 /* ------------------------------------------------------------------------ */
3473 int
ipf_nat_hashtab_add(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,nat_t * nat)3474 ipf_nat_hashtab_add(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, nat_t *nat)
3475 {
3476 	nat_t **natp;
3477 	u_int hv0;
3478 	u_int hv1;
3479 
3480 	hv0 = nat->nat_hv[0] % softn->ipf_nat_table_sz;
3481 	hv1 = nat->nat_hv[1] % softn->ipf_nat_table_sz;
3482 
3483 	if (softn->ipf_nat_stats.ns_side[0].ns_bucketlen[hv0] >=
3484 	    softn->ipf_nat_maxbucket) {
3485 		DT1(ns_bucket_max_0, int,
3486 		    softn->ipf_nat_stats.ns_side[0].ns_bucketlen[hv0]);
3487 		NBUMPSIDE(0, ns_bucket_max);
3488 		return -1;
3489 	}
3490 
3491 	if (softn->ipf_nat_stats.ns_side[1].ns_bucketlen[hv1] >=
3492 	    softn->ipf_nat_maxbucket) {
3493 		DT1(ns_bucket_max_1, int,
3494 		    softn->ipf_nat_stats.ns_side[1].ns_bucketlen[hv1]);
3495 		NBUMPSIDE(1, ns_bucket_max);
3496 		return -1;
3497 	}
3498 
3499 	/*
3500 	 * The ordering of operations in the list and hash table insertion
3501 	 * is very important.  The last operation for each task should be
3502 	 * to update the top of the list, after all the "nexts" have been
3503 	 * done so that walking the list while it is being done does not
3504 	 * find strange pointers.
3505 	 *
3506 	 * Global list of NAT instances
3507 	 */
3508 	nat->nat_next = softn->ipf_nat_instances;
3509 	nat->nat_pnext = &softn->ipf_nat_instances;
3510 	if (softn->ipf_nat_instances)
3511 		softn->ipf_nat_instances->nat_pnext = &nat->nat_next;
3512 	softn->ipf_nat_instances = nat;
3513 
3514 	/*
3515 	 * Inbound hash table.
3516 	 */
3517 	natp = &softn->ipf_nat_table[0][hv0];
3518 	nat->nat_phnext[0] = natp;
3519 	nat->nat_hnext[0] = *natp;
3520 	if (*natp) {
3521 		(*natp)->nat_phnext[0] = &nat->nat_hnext[0];
3522 	} else {
3523 		NBUMPSIDE(0, ns_inuse);
3524 	}
3525 	*natp = nat;
3526 	NBUMPSIDE(0, ns_bucketlen[hv0]);
3527 
3528 	/*
3529 	 * Outbound hash table.
3530 	 */
3531 	natp = &softn->ipf_nat_table[1][hv1];
3532 	nat->nat_phnext[1] = natp;
3533 	nat->nat_hnext[1] = *natp;
3534 	if (*natp)
3535 		(*natp)->nat_phnext[1] = &nat->nat_hnext[1];
3536 	else {
3537 		NBUMPSIDE(1, ns_inuse);
3538 	}
3539 	*natp = nat;
3540 	NBUMPSIDE(1, ns_bucketlen[hv1]);
3541 
3542 	ipf_nat_setqueue(softc, softn, nat);
3543 
3544 	if (nat->nat_dir & NAT_OUTBOUND) {
3545 		NBUMPSIDE(1, ns_added);
3546 	} else {
3547 		NBUMPSIDE(0, ns_added);
3548 	}
3549 	softn->ipf_nat_stats.ns_active++;
3550 	return 0;
3551 }
3552 
3553 
3554 /* ------------------------------------------------------------------------ */
3555 /* Function:    ipf_nat_icmperrorlookup                                     */
3556 /* Returns:     nat_t* - point to matching NAT structure                    */
3557 /* Parameters:  fin(I) - pointer to packet information                      */
3558 /*              dir(I) - direction of packet (in/out)                       */
3559 /*                                                                          */
3560 /* Check if the ICMP error message is related to an existing TCP, UDP or    */
3561 /* ICMP query nat entry.  It is assumed that the packet is already of the   */
3562 /* the required length.                                                     */
3563 /* ------------------------------------------------------------------------ */
3564 nat_t *
ipf_nat_icmperrorlookup(fr_info_t * fin,int dir)3565 ipf_nat_icmperrorlookup(fr_info_t *fin, int dir)
3566 {
3567 	ipf_main_softc_t *softc = fin->fin_main_soft;
3568 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
3569 	int flags = 0, minlen;
3570 	icmphdr_t *orgicmp;
3571 	nat_stat_side_t *nside;
3572 	tcphdr_t *tcp = NULL;
3573 	u_short data[2];
3574 	nat_t *nat;
3575 	ip_t *oip;
3576 	u_int p;
3577 
3578 	nside = &softn->ipf_nat_stats.ns_side[fin->fin_out];
3579 	/*
3580 	 * Does it at least have the return (basic) IP header ?
3581 	 * Only a basic IP header (no options) should be with an ICMP error
3582 	 * header.  Also, if it's not an error type, then return.
3583 	 */
3584 	if ((fin->fin_hlen != sizeof(ip_t)) || !(fin->fin_flx & FI_ICMPERR)) {
3585 		ATOMIC_INCL(nside->ns_icmp_basic);
3586 		return NULL;
3587 	}
3588 
3589 	/*
3590 	 * Check packet size
3591 	 */
3592 	oip = (ip_t *)((char *)fin->fin_dp + 8);
3593 	minlen = IP_HL(oip) << 2;
3594 	if ((minlen < sizeof(ip_t)) ||
3595 	    (fin->fin_plen < ICMPERR_IPICMPHLEN + minlen)) {
3596 		ATOMIC_INCL(nside->ns_icmp_size);
3597 		return NULL;
3598 	}
3599 
3600 	/*
3601 	 * Is the buffer big enough for all of it ?  It's the size of the IP
3602 	 * header claimed in the encapsulated part which is of concern.  It
3603 	 * may be too big to be in this buffer but not so big that it's
3604 	 * outside the ICMP packet, leading to TCP deref's causing problems.
3605 	 * This is possible because we don't know how big oip_hl is when we
3606 	 * do the pullup early in ipf_check() and thus can't gaurantee it is
3607 	 * all here now.
3608 	 */
3609 #ifdef  ipf_nat_KERNEL
3610 	{
3611 	mb_t *m;
3612 
3613 	m = fin->fin_m;
3614 # if defined(MENTAT)
3615 	if ((char *)oip + fin->fin_dlen - ICMPERR_ICMPHLEN >
3616 	    (char *)m->b_wptr) {
3617 		ATOMIC_INCL(nside->ns_icmp_mbuf);
3618 		return NULL;
3619 	}
3620 # else
3621 	if ((char *)oip + fin->fin_dlen - ICMPERR_ICMPHLEN >
3622 	    (char *)fin->fin_ip + M_LEN(m)) {
3623 		ATOMIC_INCL(nside->ns_icmp_mbuf);
3624 		return NULL;
3625 	}
3626 # endif
3627 	}
3628 #endif
3629 
3630 	if (fin->fin_daddr != oip->ip_src.s_addr) {
3631 		ATOMIC_INCL(nside->ns_icmp_address);
3632 		return NULL;
3633 	}
3634 
3635 	p = oip->ip_p;
3636 	if (p == IPPROTO_TCP)
3637 		flags = IPN_TCP;
3638 	else if (p == IPPROTO_UDP)
3639 		flags = IPN_UDP;
3640 	else if (p == IPPROTO_ICMP) {
3641 		orgicmp = (icmphdr_t *)((char *)oip + (IP_HL(oip) << 2));
3642 
3643 		/* see if this is related to an ICMP query */
3644 		if (ipf_nat_icmpquerytype(orgicmp->icmp_type)) {
3645 			data[0] = fin->fin_data[0];
3646 			data[1] = fin->fin_data[1];
3647 			fin->fin_data[0] = 0;
3648 			fin->fin_data[1] = orgicmp->icmp_id;
3649 
3650 			flags = IPN_ICMPERR|IPN_ICMPQUERY;
3651 			/*
3652 			 * NOTE : dir refers to the direction of the original
3653 			 *        ip packet. By definition the icmp error
3654 			 *        message flows in the opposite direction.
3655 			 */
3656 			if (dir == NAT_INBOUND)
3657 				nat = ipf_nat_inlookup(fin, flags, p,
3658 						       oip->ip_dst,
3659 						       oip->ip_src);
3660 			else
3661 				nat = ipf_nat_outlookup(fin, flags, p,
3662 							oip->ip_dst,
3663 							oip->ip_src);
3664 			fin->fin_data[0] = data[0];
3665 			fin->fin_data[1] = data[1];
3666 			return nat;
3667 		}
3668 	}
3669 
3670 	if (flags & IPN_TCPUDP) {
3671 		minlen += 8;		/* + 64bits of data to get ports */
3672 		/* TRACE (fin,minlen) */
3673 		if (fin->fin_plen < ICMPERR_IPICMPHLEN + minlen) {
3674 			ATOMIC_INCL(nside->ns_icmp_short);
3675 			return NULL;
3676 		}
3677 
3678 		data[0] = fin->fin_data[0];
3679 		data[1] = fin->fin_data[1];
3680 		tcp = (tcphdr_t *)((char *)oip + (IP_HL(oip) << 2));
3681 		fin->fin_data[0] = ntohs(tcp->th_dport);
3682 		fin->fin_data[1] = ntohs(tcp->th_sport);
3683 
3684 		if (dir == NAT_INBOUND) {
3685 			nat = ipf_nat_inlookup(fin, flags, p, oip->ip_dst,
3686 					       oip->ip_src);
3687 		} else {
3688 			nat = ipf_nat_outlookup(fin, flags, p, oip->ip_dst,
3689 					    oip->ip_src);
3690 		}
3691 		fin->fin_data[0] = data[0];
3692 		fin->fin_data[1] = data[1];
3693 		return nat;
3694 	}
3695 	if (dir == NAT_INBOUND)
3696 		nat = ipf_nat_inlookup(fin, 0, p, oip->ip_dst, oip->ip_src);
3697 	else
3698 		nat = ipf_nat_outlookup(fin, 0, p, oip->ip_dst, oip->ip_src);
3699 
3700 	return nat;
3701 }
3702 
3703 
3704 /* ------------------------------------------------------------------------ */
3705 /* Function:    ipf_nat_icmperror                                           */
3706 /* Returns:     nat_t* - point to matching NAT structure                    */
3707 /* Parameters:  fin(I)    - pointer to packet information                   */
3708 /*              nflags(I) - NAT flags for this packet                       */
3709 /*              dir(I)    - direction of packet (in/out)                    */
3710 /*                                                                          */
3711 /* Fix up an ICMP packet which is an error message for an existing NAT      */
3712 /* session.  This will correct both packet header data and checksums.       */
3713 /*                                                                          */
3714 /* This should *ONLY* be used for incoming ICMP error packets to make sure  */
3715 /* a NAT'd ICMP packet gets correctly recognised.                           */
3716 /* ------------------------------------------------------------------------ */
3717 nat_t *
ipf_nat_icmperror(fr_info_t * fin,u_int * nflags,int dir)3718 ipf_nat_icmperror(fr_info_t *fin, u_int *nflags, int dir)
3719 {
3720 	ipf_main_softc_t *softc = fin->fin_main_soft;
3721 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
3722 	u_32_t sum1, sum2, sumd, sumd2;
3723 	struct in_addr a1, a2, a3, a4;
3724 	int flags, dlen, odst;
3725 	icmphdr_t *icmp;
3726 	u_short *csump;
3727 	tcphdr_t *tcp;
3728 	nat_t *nat;
3729 	ip_t *oip;
3730 	void *dp;
3731 
3732 	if ((fin->fin_flx & (FI_SHORT|FI_FRAGBODY))) {
3733 		NBUMPSIDED(fin->fin_out, ns_icmp_short);
3734 		return NULL;
3735 	}
3736 
3737 	/*
3738 	 * ipf_nat_icmperrorlookup() will return NULL for `defective' packets.
3739 	 */
3740 	if ((fin->fin_v != 4) || !(nat = ipf_nat_icmperrorlookup(fin, dir))) {
3741 		NBUMPSIDED(fin->fin_out, ns_icmp_notfound);
3742 		return NULL;
3743 	}
3744 
3745 	tcp = NULL;
3746 	csump = NULL;
3747 	flags = 0;
3748 	sumd2 = 0;
3749 	*nflags = IPN_ICMPERR;
3750 	icmp = fin->fin_dp;
3751 	oip = (ip_t *)&icmp->icmp_ip;
3752 	dp = (((char *)oip) + (IP_HL(oip) << 2));
3753 	if (oip->ip_p == IPPROTO_TCP) {
3754 		tcp = (tcphdr_t *)dp;
3755 		csump = (u_short *)&tcp->th_sum;
3756 		flags = IPN_TCP;
3757 	} else if (oip->ip_p == IPPROTO_UDP) {
3758 		udphdr_t *udp;
3759 
3760 		udp = (udphdr_t *)dp;
3761 		tcp = (tcphdr_t *)dp;
3762 		csump = (u_short *)&udp->uh_sum;
3763 		flags = IPN_UDP;
3764 	} else if (oip->ip_p == IPPROTO_ICMP)
3765 		flags = IPN_ICMPQUERY;
3766 	dlen = fin->fin_plen - ((char *)dp - (char *)fin->fin_ip);
3767 
3768 	/*
3769 	 * Need to adjust ICMP header to include the real IP#'s and
3770 	 * port #'s.  Only apply a checksum change relative to the
3771 	 * IP address change as it will be modified again in ipf_nat_checkout
3772 	 * for both address and port.  Two checksum changes are
3773 	 * necessary for the two header address changes.  Be careful
3774 	 * to only modify the checksum once for the port # and twice
3775 	 * for the IP#.
3776 	 */
3777 
3778 	/*
3779 	 * Step 1
3780 	 * Fix the IP addresses in the offending IP packet. You also need
3781 	 * to adjust the IP header checksum of that offending IP packet.
3782 	 *
3783 	 * Normally, you would expect that the ICMP checksum of the
3784 	 * ICMP error message needs to be adjusted as well for the
3785 	 * IP address change in oip.
3786 	 * However, this is a NOP, because the ICMP checksum is
3787 	 * calculated over the complete ICMP packet, which includes the
3788 	 * changed oip IP addresses and oip->ip_sum. However, these
3789 	 * two changes cancel each other out (if the delta for
3790 	 * the IP address is x, then the delta for ip_sum is minus x),
3791 	 * so no change in the icmp_cksum is necessary.
3792 	 *
3793 	 * Inbound ICMP
3794 	 * ------------
3795 	 * MAP rule, SRC=a,DST=b -> SRC=c,DST=b
3796 	 * - response to outgoing packet (a,b)=>(c,b) (OIP_SRC=c,OIP_DST=b)
3797 	 * - OIP_SRC(c)=nat_newsrcip,          OIP_DST(b)=nat_newdstip
3798 	 *=> OIP_SRC(c)=nat_oldsrcip,          OIP_DST(b)=nat_olddstip
3799 	 *
3800 	 * RDR rule, SRC=a,DST=b -> SRC=a,DST=c
3801 	 * - response to outgoing packet (c,a)=>(b,a) (OIP_SRC=b,OIP_DST=a)
3802 	 * - OIP_SRC(b)=nat_olddstip,          OIP_DST(a)=nat_oldsrcip
3803 	 *=> OIP_SRC(b)=nat_newdstip,          OIP_DST(a)=nat_newsrcip
3804 	 *
3805 	 * REWRITE out rule, SRC=a,DST=b -> SRC=c,DST=d
3806 	 * - response to outgoing packet (a,b)=>(c,d) (OIP_SRC=c,OIP_DST=d)
3807 	 * - OIP_SRC(c)=nat_newsrcip,          OIP_DST(d)=nat_newdstip
3808 	 *=> OIP_SRC(c)=nat_oldsrcip,          OIP_DST(d)=nat_olddstip
3809 	 *
3810 	 * REWRITE in rule, SRC=a,DST=b -> SRC=c,DST=d
3811 	 * - response to outgoing packet (d,c)=>(b,a) (OIP_SRC=b,OIP_DST=a)
3812 	 * - OIP_SRC(b)=nat_olddstip,          OIP_DST(a)=nat_oldsrcip
3813 	 *=> OIP_SRC(b)=nat_newdstip,          OIP_DST(a)=nat_newsrcip
3814 	 *
3815 	 * Outbound ICMP
3816 	 * -------------
3817 	 * MAP rule, SRC=a,DST=b -> SRC=c,DST=b
3818 	 * - response to incoming packet (b,c)=>(b,a) (OIP_SRC=b,OIP_DST=a)
3819 	 * - OIP_SRC(b)=nat_olddstip,          OIP_DST(a)=nat_oldsrcip
3820 	 *=> OIP_SRC(b)=nat_newdstip,          OIP_DST(a)=nat_newsrcip
3821 	 *
3822 	 * RDR rule, SRC=a,DST=b -> SRC=a,DST=c
3823 	 * - response to incoming packet (a,b)=>(a,c) (OIP_SRC=a,OIP_DST=c)
3824 	 * - OIP_SRC(a)=nat_newsrcip,          OIP_DST(c)=nat_newdstip
3825 	 *=> OIP_SRC(a)=nat_oldsrcip,          OIP_DST(c)=nat_olddstip
3826 	 *
3827 	 * REWRITE out rule, SRC=a,DST=b -> SRC=c,DST=d
3828 	 * - response to incoming packet (d,c)=>(b,a) (OIP_SRC=c,OIP_DST=d)
3829 	 * - OIP_SRC(c)=nat_olddstip,          OIP_DST(d)=nat_oldsrcip
3830 	 *=> OIP_SRC(b)=nat_newdstip,          OIP_DST(a)=nat_newsrcip
3831 	 *
3832 	 * REWRITE in rule, SRC=a,DST=b -> SRC=c,DST=d
3833 	 * - response to incoming packet (a,b)=>(c,d) (OIP_SRC=b,OIP_DST=a)
3834 	 * - OIP_SRC(b)=nat_newsrcip,          OIP_DST(a)=nat_newdstip
3835 	 *=> OIP_SRC(a)=nat_oldsrcip,          OIP_DST(c)=nat_olddstip
3836 	 */
3837 
3838 	if (((fin->fin_out == 0) && ((nat->nat_redir & NAT_MAP) != 0)) ||
3839 	    ((fin->fin_out == 1) && ((nat->nat_redir & NAT_REDIRECT) != 0))) {
3840 		a1.s_addr = ntohl(nat->nat_osrcaddr);
3841 		a4.s_addr = ntohl(oip->ip_src.s_addr);
3842 		a3.s_addr = ntohl(nat->nat_odstaddr);
3843 		a2.s_addr = ntohl(oip->ip_dst.s_addr);
3844 		oip->ip_src.s_addr = htonl(a1.s_addr);
3845 		oip->ip_dst.s_addr = htonl(a3.s_addr);
3846 		odst = 1;
3847 	} else {
3848 		a1.s_addr = ntohl(nat->nat_ndstaddr);
3849 		a2.s_addr = ntohl(oip->ip_dst.s_addr);
3850 		a3.s_addr = ntohl(nat->nat_nsrcaddr);
3851 		a4.s_addr = ntohl(oip->ip_src.s_addr);
3852 		oip->ip_dst.s_addr = htonl(a3.s_addr);
3853 		oip->ip_src.s_addr = htonl(a1.s_addr);
3854 		odst = 0;
3855 	}
3856 	sum1 = 0;
3857 	sum2 = 0;
3858 	sumd = 0;
3859 	CALC_SUMD(a2.s_addr, a3.s_addr, sum1);
3860 	CALC_SUMD(a4.s_addr, a1.s_addr, sum2);
3861 	sumd = sum2 + sum1;
3862 	if (sumd != 0)
3863 		ipf_fix_datacksum(&oip->ip_sum, sumd);
3864 
3865 	sumd2 = sumd;
3866 	sum1 = 0;
3867 	sum2 = 0;
3868 
3869 	/*
3870 	 * Fix UDP pseudo header checksum to compensate for the
3871 	 * IP address change.
3872 	 */
3873 	if (((flags & IPN_TCPUDP) != 0) && (dlen >= 4)) {
3874 		u_32_t sum3, sum4, sumt;
3875 
3876 		/*
3877 		 * Step 2 :
3878 		 * For offending TCP/UDP IP packets, translate the ports as
3879 		 * well, based on the NAT specification. Of course such
3880 		 * a change may be reflected in the ICMP checksum as well.
3881 		 *
3882 		 * Since the port fields are part of the TCP/UDP checksum
3883 		 * of the offending IP packet, you need to adjust that checksum
3884 		 * as well... except that the change in the port numbers should
3885 		 * be offset by the checksum change.  However, the TCP/UDP
3886 		 * checksum will also need to change if there has been an
3887 		 * IP address change.
3888 		 */
3889 		if (odst == 1) {
3890 			sum1 = ntohs(nat->nat_osport);
3891 			sum4 = ntohs(tcp->th_sport);
3892 			sum3 = ntohs(nat->nat_odport);
3893 			sum2 = ntohs(tcp->th_dport);
3894 
3895 			tcp->th_sport = htons(sum1);
3896 			tcp->th_dport = htons(sum3);
3897 		} else {
3898 			sum1 = ntohs(nat->nat_ndport);
3899 			sum2 = ntohs(tcp->th_dport);
3900 			sum3 = ntohs(nat->nat_nsport);
3901 			sum4 = ntohs(tcp->th_sport);
3902 
3903 			tcp->th_dport = htons(sum3);
3904 			tcp->th_sport = htons(sum1);
3905 		}
3906 		CALC_SUMD(sum4, sum1, sumt);
3907 		sumd += sumt;
3908 		CALC_SUMD(sum2, sum3, sumt);
3909 		sumd += sumt;
3910 
3911 		if (sumd != 0 || sumd2 != 0) {
3912 			/*
3913 			 * At this point, sumd is the delta to apply to the
3914 			 * TCP/UDP header, given the changes in both the IP
3915 			 * address and the ports and sumd2 is the delta to
3916 			 * apply to the ICMP header, given the IP address
3917 			 * change delta that may need to be applied to the
3918 			 * TCP/UDP checksum instead.
3919 			 *
3920 			 * If we will both the IP and TCP/UDP checksums
3921 			 * then the ICMP checksum changes by the address
3922 			 * delta applied to the TCP/UDP checksum.  If we
3923 			 * do not change the TCP/UDP checksum them we
3924 			 * apply the delta in ports to the ICMP checksum.
3925 			 */
3926 			if (oip->ip_p == IPPROTO_UDP) {
3927 				if ((dlen >= 8) && (*csump != 0)) {
3928 					ipf_fix_datacksum(csump, sumd);
3929 				} else {
3930 					CALC_SUMD(sum1, sum4, sumd2);
3931 					CALC_SUMD(sum3, sum2, sumt);
3932 					sumd2 += sumt;
3933 				}
3934 			} else if (oip->ip_p == IPPROTO_TCP) {
3935 				if (dlen >= 18) {
3936 					ipf_fix_datacksum(csump, sumd);
3937 				} else {
3938 					CALC_SUMD(sum1, sum4, sumd2);
3939 					CALC_SUMD(sum3, sum2, sumt);
3940 					sumd2 += sumt;
3941 				}
3942 			}
3943 			if (sumd2 != 0) {
3944 				sumd2 = (sumd2 & 0xffff) + (sumd2 >> 16);
3945 				sumd2 = (sumd2 & 0xffff) + (sumd2 >> 16);
3946 				sumd2 = (sumd2 & 0xffff) + (sumd2 >> 16);
3947 				ipf_fix_incksum(0, &icmp->icmp_cksum, sumd2, 0);
3948 			}
3949 		}
3950 	} else if (((flags & IPN_ICMPQUERY) != 0) && (dlen >= 8)) {
3951 		icmphdr_t *orgicmp;
3952 
3953 		/*
3954 		 * XXX - what if this is bogus hl and we go off the end ?
3955 		 * In this case, ipf_nat_icmperrorlookup() will have
3956 		 * returned NULL.
3957 		 */
3958 		orgicmp = (icmphdr_t *)dp;
3959 
3960 		if (odst == 1) {
3961 			if (orgicmp->icmp_id != nat->nat_osport) {
3962 
3963 				/*
3964 				 * Fix ICMP checksum (of the offening ICMP
3965 				 * query packet) to compensate the change
3966 				 * in the ICMP id of the offending ICMP
3967 				 * packet.
3968 				 *
3969 				 * Since you modify orgicmp->icmp_id with
3970 				 * a delta (say x) and you compensate that
3971 				 * in origicmp->icmp_cksum with a delta
3972 				 * minus x, you don't have to adjust the
3973 				 * overall icmp->icmp_cksum
3974 				 */
3975 				sum1 = ntohs(orgicmp->icmp_id);
3976 				sum2 = ntohs(nat->nat_oicmpid);
3977 				CALC_SUMD(sum1, sum2, sumd);
3978 				orgicmp->icmp_id = nat->nat_oicmpid;
3979 				ipf_fix_datacksum(&orgicmp->icmp_cksum, sumd);
3980 			}
3981 		} /* nat_dir == NAT_INBOUND is impossible for icmp queries */
3982 	}
3983 	return nat;
3984 }
3985 
3986 
3987 /*
3988  *       MAP-IN    MAP-OUT   RDR-IN   RDR-OUT
3989  * osrc    X       == src    == src      X
3990  * odst    X       == dst    == dst      X
3991  * nsrc  == dst      X         X      == dst
3992  * ndst  == src      X         X      == src
3993  * MAP = NAT_OUTBOUND, RDR = NAT_INBOUND
3994  */
3995 /*
3996  * NB: these lookups don't lock access to the list, it assumed that it has
3997  * already been done!
3998  */
3999 /* ------------------------------------------------------------------------ */
4000 /* Function:    ipf_nat_inlookup                                            */
4001 /* Returns:     nat_t* - NULL == no match,                                  */
4002 /*                       else pointer to matching NAT entry                 */
4003 /* Parameters:  fin(I)    - pointer to packet information                   */
4004 /*              flags(I)  - NAT flags for this packet                       */
4005 /*              p(I)      - protocol for this packet                        */
4006 /*              src(I)    - source IP address                               */
4007 /*              mapdst(I) - destination IP address                          */
4008 /*                                                                          */
4009 /* Lookup a nat entry based on the mapped destination ip address/port and   */
4010 /* real source address/port.  We use this lookup when receiving a packet,   */
4011 /* we're looking for a table entry, based on the destination address.       */
4012 /*                                                                          */
4013 /* NOTE: THE PACKET BEING CHECKED (IF FOUND) HAS A MAPPING ALREADY.         */
4014 /*                                                                          */
4015 /* NOTE: IT IS ASSUMED THAT  IS ONLY HELD WITH A READ LOCK WHEN             */
4016 /*       THIS FUNCTION IS CALLED WITH NAT_SEARCH SET IN nflags.             */
4017 /*                                                                          */
4018 /* flags   -> relevant are IPN_UDP/IPN_TCP/IPN_ICMPQUERY that indicate if   */
4019 /*            the packet is of said protocol                                */
4020 /* ------------------------------------------------------------------------ */
4021 nat_t *
ipf_nat_inlookup(fr_info_t * fin,u_int flags,u_int p,struct in_addr src,struct in_addr mapdst)4022 ipf_nat_inlookup(fr_info_t *fin, u_int flags, u_int p, struct in_addr src,
4023     struct in_addr mapdst)
4024 {
4025 	ipf_main_softc_t *softc = fin->fin_main_soft;
4026 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
4027 	u_short sport, dport;
4028 	ipnat_t *ipn;
4029 	nat_t *nat;
4030 	int nflags;
4031 	u_32_t dst;
4032 	void *ifp;
4033 	u_int hv, rhv;
4034 
4035 	ifp = fin->fin_ifp;
4036 	dst = mapdst.s_addr;
4037 
4038 	switch (p)
4039 	{
4040 	case IPPROTO_TCP :
4041 	case IPPROTO_UDP :
4042 		sport = htons(fin->fin_data[0]);
4043 		dport = htons(fin->fin_data[1]);
4044 		break;
4045 	case IPPROTO_ICMP :
4046 		sport = 0;
4047 		dport = fin->fin_data[1];
4048 		break;
4049 	default :
4050 		sport = 0;
4051 		dport = 0;
4052 		break;
4053 	}
4054 
4055 
4056 	if ((flags & SI_WILDP) != 0)
4057 		goto find_in_wild_ports;
4058 
4059 	rhv = NAT_HASH_FN(dst, dport, 0xffffffff);
4060 	rhv = NAT_HASH_FN(src.s_addr, rhv + sport, 0xffffffff);
4061 	hv = rhv % softn->ipf_nat_table_sz;
4062 	nat = softn->ipf_nat_table[1][hv];
4063 	/* TRACE dst, dport, src, sport, hv, nat */
4064 
4065 	for (; nat; nat = nat->nat_hnext[1]) {
4066 		if (nat->nat_ifps[0] != NULL) {
4067 			if ((ifp != NULL) && (ifp != nat->nat_ifps[0]))
4068 				continue;
4069 		}
4070 
4071 		if (nat->nat_pr[0] != p)
4072 			continue;
4073 
4074 		switch (nat->nat_dir)
4075 		{
4076 		case NAT_INBOUND :
4077 		case NAT_DIVERTIN :
4078 			if (nat->nat_v[0] != 4)
4079 				continue;
4080 			if (nat->nat_osrcaddr != src.s_addr ||
4081 			    nat->nat_odstaddr != dst)
4082 				continue;
4083 			if ((nat->nat_flags & IPN_TCPUDP) != 0) {
4084 				if (nat->nat_osport != sport)
4085 					continue;
4086 				if (nat->nat_odport != dport)
4087 					continue;
4088 
4089 			} else if (p == IPPROTO_ICMP) {
4090 				if (nat->nat_oicmpid != dport) {
4091 					continue;
4092 				}
4093 			}
4094 			break;
4095 		case NAT_DIVERTOUT :
4096 			if (nat->nat_dlocal)
4097 				continue;
4098 			/* FALLTHROUGH */
4099 		case NAT_OUTBOUND :
4100 			if (nat->nat_v[1] != 4)
4101 				continue;
4102 			if (nat->nat_dlocal)
4103 				continue;
4104 			if (nat->nat_dlocal)
4105 				continue;
4106 			if (nat->nat_ndstaddr != src.s_addr ||
4107 			    nat->nat_nsrcaddr != dst)
4108 				continue;
4109 			if ((nat->nat_flags & IPN_TCPUDP) != 0) {
4110 				if (nat->nat_ndport != sport)
4111 					continue;
4112 				if (nat->nat_nsport != dport)
4113 					continue;
4114 
4115 			} else if (p == IPPROTO_ICMP) {
4116 				if (nat->nat_nicmpid != dport) {
4117 					continue;
4118 				}
4119 			}
4120 			break;
4121 		}
4122 
4123 
4124 		if ((nat->nat_flags & IPN_TCPUDP) != 0) {
4125 			ipn = nat->nat_ptr;
4126 			if ((ipn != NULL) && (nat->nat_aps != NULL))
4127 				if (ipf_proxy_match(fin, nat) != 0)
4128 					continue;
4129 		}
4130 		if ((nat->nat_ifps[0] == NULL) && (ifp != NULL)) {
4131 			nat->nat_ifps[0] = ifp;
4132 			nat->nat_mtu[0] = GETIFMTU_4(ifp);
4133 		}
4134 		return nat;
4135 	}
4136 
4137 	/*
4138 	 * So if we didn't find it but there are wildcard members in the hash
4139 	 * table, go back and look for them.  We do this search and update here
4140 	 * because it is modifying the NAT table and we want to do this only
4141 	 * for the first packet that matches.  The exception, of course, is
4142 	 * for "dummy" (FI_IGNORE) lookups.
4143 	 */
4144 find_in_wild_ports:
4145 	if (!(flags & NAT_TCPUDP) || !(flags & NAT_SEARCH)) {
4146 		NBUMPSIDEX(0, ns_lookup_miss, ns_lookup_miss_0);
4147 		return NULL;
4148 	}
4149 	if (softn->ipf_nat_stats.ns_wilds == 0 || (fin->fin_flx & FI_NOWILD)) {
4150 		NBUMPSIDEX(0, ns_lookup_nowild, ns_lookup_nowild_0);
4151 		return NULL;
4152 	}
4153 
4154 	RWLOCK_EXIT(&softc->ipf_nat);
4155 
4156 	hv = NAT_HASH_FN(dst, 0, 0xffffffff);
4157 	hv = NAT_HASH_FN(src.s_addr, hv, softn->ipf_nat_table_sz);
4158 	WRITE_ENTER(&softc->ipf_nat);
4159 
4160 	nat = softn->ipf_nat_table[1][hv];
4161 	/* TRACE dst, src, hv, nat */
4162 	for (; nat; nat = nat->nat_hnext[1]) {
4163 		if (nat->nat_ifps[0] != NULL) {
4164 			if ((ifp != NULL) && (ifp != nat->nat_ifps[0]))
4165 				continue;
4166 		}
4167 
4168 		if (nat->nat_pr[0] != fin->fin_p)
4169 			continue;
4170 
4171 		switch (nat->nat_dir & (NAT_INBOUND|NAT_OUTBOUND))
4172 		{
4173 		case NAT_INBOUND :
4174 			if (nat->nat_v[0] != 4)
4175 				continue;
4176 			if (nat->nat_osrcaddr != src.s_addr ||
4177 			    nat->nat_odstaddr != dst)
4178 				continue;
4179 			break;
4180 		case NAT_OUTBOUND :
4181 			if (nat->nat_v[1] != 4)
4182 				continue;
4183 			if (nat->nat_ndstaddr != src.s_addr ||
4184 			    nat->nat_nsrcaddr != dst)
4185 				continue;
4186 			break;
4187 		}
4188 
4189 		nflags = nat->nat_flags;
4190 		if (!(nflags & (NAT_TCPUDP|SI_WILDP)))
4191 			continue;
4192 
4193 		if (ipf_nat_wildok(nat, (int)sport, (int)dport, nflags,
4194 				   NAT_INBOUND) == 1) {
4195 			if ((fin->fin_flx & FI_IGNORE) != 0)
4196 				break;
4197 			if ((nflags & SI_CLONE) != 0) {
4198 				nat = ipf_nat_clone(fin, nat);
4199 				if (nat == NULL)
4200 					break;
4201 			} else {
4202 				MUTEX_ENTER(&softn->ipf_nat_new);
4203 				softn->ipf_nat_stats.ns_wilds--;
4204 				MUTEX_EXIT(&softn->ipf_nat_new);
4205 			}
4206 
4207 			if (nat->nat_dir == NAT_INBOUND) {
4208 				if (nat->nat_osport == 0) {
4209 					nat->nat_osport = sport;
4210 					nat->nat_nsport = sport;
4211 				}
4212 				if (nat->nat_odport == 0) {
4213 					nat->nat_odport = dport;
4214 					nat->nat_ndport = dport;
4215 				}
4216 			} else if (nat->nat_dir == NAT_OUTBOUND) {
4217 				if (nat->nat_osport == 0) {
4218 					nat->nat_osport = dport;
4219 					nat->nat_nsport = dport;
4220 				}
4221 				if (nat->nat_odport == 0) {
4222 					nat->nat_odport = sport;
4223 					nat->nat_ndport = sport;
4224 				}
4225 			}
4226 			if ((nat->nat_ifps[0] == NULL) && (ifp != NULL)) {
4227 				nat->nat_ifps[0] = ifp;
4228 				nat->nat_mtu[0] = GETIFMTU_4(ifp);
4229 			}
4230 			nat->nat_flags &= ~(SI_W_DPORT|SI_W_SPORT);
4231 			ipf_nat_tabmove(softn, nat);
4232 			break;
4233 		}
4234 	}
4235 
4236 	MUTEX_DOWNGRADE(&softc->ipf_nat);
4237 
4238 	if (nat == NULL) {
4239 		NBUMPSIDE(0, ns_lookup_miss);
4240 	}
4241 	return nat;
4242 }
4243 
4244 
4245 /* ------------------------------------------------------------------------ */
4246 /* Function:    ipf_nat_tabmove                                             */
4247 /* Returns:     Nil                                                         */
4248 /* Parameters:  softn(I) - pointer to NAT context structure                 */
4249 /*              nat(I)   - pointer to NAT structure                         */
4250 /* Write Lock:  ipf_nat                                                     */
4251 /*                                                                          */
4252 /* This function is only called for TCP/UDP NAT table entries where the     */
4253 /* original was placed in the table without hashing on the ports and we now */
4254 /* want to include hashing on port numbers.                                 */
4255 /* ------------------------------------------------------------------------ */
4256 static void
ipf_nat_tabmove(ipf_nat_softc_t * softn,nat_t * nat)4257 ipf_nat_tabmove(ipf_nat_softc_t *softn, nat_t *nat)
4258 {
4259 	u_int hv0, hv1, rhv0, rhv1;
4260 	natstat_t *nsp;
4261 	nat_t **natp;
4262 
4263 	if (nat->nat_flags & SI_CLONE)
4264 		return;
4265 
4266 	nsp = &softn->ipf_nat_stats;
4267 	/*
4268 	 * Remove the NAT entry from the old location
4269 	 */
4270 	if (nat->nat_hnext[0])
4271 		nat->nat_hnext[0]->nat_phnext[0] = nat->nat_phnext[0];
4272 	*nat->nat_phnext[0] = nat->nat_hnext[0];
4273 	hv0 = nat->nat_hv[0] % softn->ipf_nat_table_sz;
4274 	hv1 = nat->nat_hv[1] % softn->ipf_nat_table_sz;
4275 
4276 	ASSERT(nsp->ns_side[0].ns_bucketlen[hv0] > 0);
4277 	nsp->ns_side[0].ns_bucketlen[hv0]--;
4278 
4279 	if (nat->nat_hnext[1])
4280 		nat->nat_hnext[1]->nat_phnext[1] = nat->nat_phnext[1];
4281 	*nat->nat_phnext[1] = nat->nat_hnext[1];
4282 	ASSERT(nsp->ns_side[1].ns_bucketlen[hv1] > 0);
4283 	nsp->ns_side[1].ns_bucketlen[hv1]--;
4284 
4285 	/*
4286 	 * Add into the NAT table in the new position
4287 	 */
4288 	rhv0 = NAT_HASH_FN(nat->nat_osrcaddr, nat->nat_osport, 0xffffffff);
4289 	rhv0 = NAT_HASH_FN(nat->nat_odstaddr, rhv0 + nat->nat_odport,
4290 			   0xffffffff);
4291 	rhv1 = NAT_HASH_FN(nat->nat_nsrcaddr, nat->nat_nsport, 0xffffffff);
4292 	rhv1 = NAT_HASH_FN(nat->nat_ndstaddr, rhv1 + nat->nat_ndport,
4293 			   0xffffffff);
4294 
4295 	if ((nat->nat_dir & NAT_OUTBOUND) == NAT_OUTBOUND) {
4296 		nat->nat_hv[0] = rhv0;
4297 		nat->nat_hv[1] = rhv1;
4298 	} else {
4299 		nat->nat_hv[0] = rhv1;
4300 		nat->nat_hv[1] = rhv0;
4301 	}
4302 
4303 	hv0 = nat->nat_hv[0] % softn->ipf_nat_table_sz;
4304 	hv1 = nat->nat_hv[1] % softn->ipf_nat_table_sz;
4305 
4306 	/* TRACE nat_osrcaddr, nat_osport, nat_odstaddr, nat_odport, hv0 */
4307 	/* TRACE nat_nsrcaddr, nat_nsport, nat_ndstaddr, nat_ndport, hv1 */
4308 
4309 	natp = &softn->ipf_nat_table[0][hv0];
4310 	if (*natp)
4311 		(*natp)->nat_phnext[0] = &nat->nat_hnext[0];
4312 	nat->nat_phnext[0] = natp;
4313 	nat->nat_hnext[0] = *natp;
4314 	*natp = nat;
4315 	nsp->ns_side[0].ns_bucketlen[hv0]++;
4316 
4317 	natp = &softn->ipf_nat_table[1][hv1];
4318 	if (*natp)
4319 		(*natp)->nat_phnext[1] = &nat->nat_hnext[1];
4320 	nat->nat_phnext[1] = natp;
4321 	nat->nat_hnext[1] = *natp;
4322 	*natp = nat;
4323 	nsp->ns_side[1].ns_bucketlen[hv1]++;
4324 }
4325 
4326 
4327 /* ------------------------------------------------------------------------ */
4328 /* Function:    ipf_nat_outlookup                                           */
4329 /* Returns:     nat_t* - NULL == no match,                                  */
4330 /*                       else pointer to matching NAT entry                 */
4331 /* Parameters:  fin(I)   - pointer to packet information                    */
4332 /*              flags(I) - NAT flags for this packet                        */
4333 /*              p(I)     - protocol for this packet                         */
4334 /*              src(I)   - source IP address                                */
4335 /*              dst(I)   - destination IP address                           */
4336 /*              rw(I)    - 1 == write lock on  held, 0 == read lock.        */
4337 /*                                                                          */
4338 /* Lookup a nat entry based on the source 'real' ip address/port and        */
4339 /* destination address/port.  We use this lookup when sending a packet out, */
4340 /* we're looking for a table entry, based on the source address.            */
4341 /*                                                                          */
4342 /* NOTE: THE PACKET BEING CHECKED (IF FOUND) HAS A MAPPING ALREADY.         */
4343 /*                                                                          */
4344 /* NOTE: IT IS ASSUMED THAT  IS ONLY HELD WITH A READ LOCK WHEN             */
4345 /*       THIS FUNCTION IS CALLED WITH NAT_SEARCH SET IN nflags.             */
4346 /*                                                                          */
4347 /* flags   -> relevant are IPN_UDP/IPN_TCP/IPN_ICMPQUERY that indicate if   */
4348 /*            the packet is of said protocol                                */
4349 /* ------------------------------------------------------------------------ */
4350 nat_t *
ipf_nat_outlookup(fr_info_t * fin,u_int flags,u_int p,struct in_addr src,struct in_addr dst)4351 ipf_nat_outlookup(fr_info_t *fin, u_int flags, u_int p, struct in_addr src,
4352    struct in_addr dst)
4353 {
4354 	ipf_main_softc_t *softc = fin->fin_main_soft;
4355 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
4356 	u_short sport, dport;
4357 	ipnat_t *ipn;
4358 	nat_t *nat;
4359 	void *ifp;
4360 	u_int hv;
4361 
4362 	ifp = fin->fin_ifp;
4363 
4364 	switch (p)
4365 	{
4366 	case IPPROTO_TCP :
4367 	case IPPROTO_UDP :
4368 		sport = htons(fin->fin_data[0]);
4369 		dport = htons(fin->fin_data[1]);
4370 		break;
4371 	case IPPROTO_ICMP :
4372 		sport = 0;
4373 		dport = fin->fin_data[1];
4374 		break;
4375 	default :
4376 		sport = 0;
4377 		dport = 0;
4378 		break;
4379 	}
4380 
4381 	if ((flags & SI_WILDP) != 0)
4382 		goto find_out_wild_ports;
4383 
4384 	hv = NAT_HASH_FN(src.s_addr, sport, 0xffffffff);
4385 	hv = NAT_HASH_FN(dst.s_addr, hv + dport, softn->ipf_nat_table_sz);
4386 	nat = softn->ipf_nat_table[0][hv];
4387 
4388 	/* TRACE src, sport, dst, dport, hv, nat */
4389 
4390 	for (; nat; nat = nat->nat_hnext[0]) {
4391 		if (nat->nat_ifps[1] != NULL) {
4392 			if ((ifp != NULL) && (ifp != nat->nat_ifps[1]))
4393 				continue;
4394 		}
4395 
4396 		if (nat->nat_pr[1] != p)
4397 			continue;
4398 
4399 		switch (nat->nat_dir)
4400 		{
4401 		case NAT_INBOUND :
4402 		case NAT_DIVERTIN :
4403 			if (nat->nat_v[1] != 4)
4404 				continue;
4405 			if (nat->nat_ndstaddr != src.s_addr ||
4406 			    nat->nat_nsrcaddr != dst.s_addr)
4407 				continue;
4408 
4409 			if ((nat->nat_flags & IPN_TCPUDP) != 0) {
4410 				if (nat->nat_ndport != sport)
4411 					continue;
4412 				if (nat->nat_nsport != dport)
4413 					continue;
4414 
4415 			} else if (p == IPPROTO_ICMP) {
4416 				if (nat->nat_nicmpid != dport) {
4417 					continue;
4418 				}
4419 			}
4420 			break;
4421 		case NAT_OUTBOUND :
4422 		case NAT_DIVERTOUT :
4423 			if (nat->nat_v[0] != 4)
4424 				continue;
4425 			if (nat->nat_osrcaddr != src.s_addr ||
4426 			    nat->nat_odstaddr != dst.s_addr)
4427 				continue;
4428 
4429 			if ((nat->nat_flags & IPN_TCPUDP) != 0) {
4430 				if (nat->nat_odport != dport)
4431 					continue;
4432 				if (nat->nat_osport != sport)
4433 					continue;
4434 
4435 			} else if (p == IPPROTO_ICMP) {
4436 				if (nat->nat_oicmpid != dport) {
4437 					continue;
4438 				}
4439 			}
4440 			break;
4441 		}
4442 
4443 		ipn = nat->nat_ptr;
4444 		if ((ipn != NULL) && (nat->nat_aps != NULL))
4445 			if (ipf_proxy_match(fin, nat) != 0)
4446 				continue;
4447 
4448 		if ((nat->nat_ifps[1] == NULL) && (ifp != NULL)) {
4449 			nat->nat_ifps[1] = ifp;
4450 			nat->nat_mtu[1] = GETIFMTU_4(ifp);
4451 		}
4452 		return nat;
4453 	}
4454 
4455 	/*
4456 	 * So if we didn't find it but there are wildcard members in the hash
4457 	 * table, go back and look for them.  We do this search and update here
4458 	 * because it is modifying the NAT table and we want to do this only
4459 	 * for the first packet that matches.  The exception, of course, is
4460 	 * for "dummy" (FI_IGNORE) lookups.
4461 	 */
4462 find_out_wild_ports:
4463 	if (!(flags & NAT_TCPUDP) || !(flags & NAT_SEARCH)) {
4464 		NBUMPSIDEX(1, ns_lookup_miss, ns_lookup_miss_1);
4465 		return NULL;
4466 	}
4467 	if (softn->ipf_nat_stats.ns_wilds == 0 || (fin->fin_flx & FI_NOWILD)) {
4468 		NBUMPSIDEX(1, ns_lookup_nowild, ns_lookup_nowild_1);
4469 		return NULL;
4470 	}
4471 
4472 	RWLOCK_EXIT(&softc->ipf_nat);
4473 
4474 	hv = NAT_HASH_FN(src.s_addr, 0, 0xffffffff);
4475 	hv = NAT_HASH_FN(dst.s_addr, hv, softn->ipf_nat_table_sz);
4476 
4477 	WRITE_ENTER(&softc->ipf_nat);
4478 
4479 	nat = softn->ipf_nat_table[0][hv];
4480 	for (; nat; nat = nat->nat_hnext[0]) {
4481 		if (nat->nat_ifps[1] != NULL) {
4482 			if ((ifp != NULL) && (ifp != nat->nat_ifps[1]))
4483 				continue;
4484 		}
4485 
4486 		if (nat->nat_pr[1] != fin->fin_p)
4487 			continue;
4488 
4489 		switch (nat->nat_dir & (NAT_INBOUND|NAT_OUTBOUND))
4490 		{
4491 		case NAT_INBOUND :
4492 			if (nat->nat_v[1] != 4)
4493 				continue;
4494 			if (nat->nat_ndstaddr != src.s_addr ||
4495 			    nat->nat_nsrcaddr != dst.s_addr)
4496 				continue;
4497 			break;
4498 		case NAT_OUTBOUND :
4499 			if (nat->nat_v[0] != 4)
4500 				continue;
4501 			if (nat->nat_osrcaddr != src.s_addr ||
4502 			    nat->nat_odstaddr != dst.s_addr)
4503 				continue;
4504 			break;
4505 		}
4506 
4507 		if (!(nat->nat_flags & (NAT_TCPUDP|SI_WILDP)))
4508 			continue;
4509 
4510 		if (ipf_nat_wildok(nat, (int)sport, (int)dport, nat->nat_flags,
4511 				   NAT_OUTBOUND) == 1) {
4512 			if ((fin->fin_flx & FI_IGNORE) != 0)
4513 				break;
4514 			if ((nat->nat_flags & SI_CLONE) != 0) {
4515 				nat = ipf_nat_clone(fin, nat);
4516 				if (nat == NULL)
4517 					break;
4518 			} else {
4519 				MUTEX_ENTER(&softn->ipf_nat_new);
4520 				softn->ipf_nat_stats.ns_wilds--;
4521 				MUTEX_EXIT(&softn->ipf_nat_new);
4522 			}
4523 
4524 			if (nat->nat_dir == NAT_OUTBOUND) {
4525 				if (nat->nat_osport == 0) {
4526 					nat->nat_osport = sport;
4527 					nat->nat_nsport = sport;
4528 				}
4529 				if (nat->nat_odport == 0) {
4530 					nat->nat_odport = dport;
4531 					nat->nat_ndport = dport;
4532 				}
4533 			} else if (nat->nat_dir == NAT_INBOUND) {
4534 				if (nat->nat_osport == 0) {
4535 					nat->nat_osport = dport;
4536 					nat->nat_nsport = dport;
4537 				}
4538 				if (nat->nat_odport == 0) {
4539 					nat->nat_odport = sport;
4540 					nat->nat_ndport = sport;
4541 				}
4542 			}
4543 			if ((nat->nat_ifps[1] == NULL) && (ifp != NULL)) {
4544 				nat->nat_ifps[1] = ifp;
4545 				nat->nat_mtu[1] = GETIFMTU_4(ifp);
4546 			}
4547 			nat->nat_flags &= ~(SI_W_DPORT|SI_W_SPORT);
4548 			ipf_nat_tabmove(softn, nat);
4549 			break;
4550 		}
4551 	}
4552 
4553 	MUTEX_DOWNGRADE(&softc->ipf_nat);
4554 
4555 	if (nat == NULL) {
4556 		NBUMPSIDE(1, ns_lookup_miss);
4557 	}
4558 	return nat;
4559 }
4560 
4561 
4562 /* ------------------------------------------------------------------------ */
4563 /* Function:    ipf_nat_lookupredir                                         */
4564 /* Returns:     nat_t* - NULL == no match,                                  */
4565 /*                       else pointer to matching NAT entry                 */
4566 /* Parameters:  softc(I) - pointer to soft context main structure           */
4567 /*              np(I)    - pointer to description of packet to find NAT     */
4568 /*                         table entry for.                                 */
4569 /*                                                                          */
4570 /* Lookup the NAT tables to search for a matching redirect                  */
4571 /* The contents of natlookup_t should imitate those found in a packet that  */
4572 /* would be translated - ie a packet coming in for RDR or going out for MAP.*/
4573 /* We can do the lookup in one of two ways, imitating an inbound or         */
4574 /* outbound  packet.  By default we assume outbound, unless IPN_IN is set.  */
4575 /* For IN, the fields are set as follows:                                   */
4576 /*     nl_real* = source information                                        */
4577 /*     nl_out* = destination information (translated)                       */
4578 /* For an out packet, the fields are set like this:                         */
4579 /*     nl_in* = source information (untranslated)                           */
4580 /*     nl_out* = destination information (translated)                       */
4581 /* ------------------------------------------------------------------------ */
4582 nat_t *
ipf_nat_lookupredir(ipf_main_softc_t * softc,natlookup_t * np)4583 ipf_nat_lookupredir(ipf_main_softc_t *softc, natlookup_t *np)
4584 {
4585 	fr_info_t fi;
4586 	nat_t *nat;
4587 
4588 	bzero((char *)&fi, sizeof(fi));
4589 	fi.fin_main_soft = softc;
4590 	if (np->nl_flags & IPN_IN) {
4591 		fi.fin_data[0] = ntohs(np->nl_realport);
4592 		fi.fin_data[1] = ntohs(np->nl_outport);
4593 	} else {
4594 		fi.fin_data[0] = ntohs(np->nl_inport);
4595 		fi.fin_data[1] = ntohs(np->nl_outport);
4596 	}
4597 	if (np->nl_flags & IPN_TCP)
4598 		fi.fin_p = IPPROTO_TCP;
4599 	else if (np->nl_flags & IPN_UDP)
4600 		fi.fin_p = IPPROTO_UDP;
4601 	else if (np->nl_flags & (IPN_ICMPERR|IPN_ICMPQUERY))
4602 		fi.fin_p = IPPROTO_ICMP;
4603 
4604 	/*
4605 	 * We can do two sorts of lookups:
4606 	 * - IPN_IN: we have the `real' and `out' address, look for `in'.
4607 	 * - default: we have the `in' and `out' address, look for `real'.
4608 	 */
4609 	if (np->nl_flags & IPN_IN) {
4610 		if ((nat = ipf_nat_inlookup(&fi, np->nl_flags, fi.fin_p,
4611 					    np->nl_realip, np->nl_outip))) {
4612 			np->nl_inip = nat->nat_odstip;
4613 			np->nl_inport = nat->nat_odport;
4614 		}
4615 	} else {
4616 		/*
4617 		 * If nl_inip is non null, this is a lookup based on the real
4618 		 * ip address. Else, we use the fake.
4619 		 */
4620 		if ((nat = ipf_nat_outlookup(&fi, np->nl_flags, fi.fin_p,
4621 					 np->nl_inip, np->nl_outip))) {
4622 
4623 			if ((np->nl_flags & IPN_FINDFORWARD) != 0) {
4624 				fr_info_t fin;
4625 				bzero((char *)&fin, sizeof(fin));
4626 				fin.fin_p = nat->nat_pr[0];
4627 				fin.fin_data[0] = ntohs(nat->nat_ndport);
4628 				fin.fin_data[1] = ntohs(nat->nat_nsport);
4629 				if (ipf_nat_inlookup(&fin, np->nl_flags,
4630 						     fin.fin_p, nat->nat_ndstip,
4631 						     nat->nat_nsrcip) != NULL) {
4632 					np->nl_flags &= ~IPN_FINDFORWARD;
4633 				}
4634 			}
4635 
4636 			np->nl_realip = nat->nat_odstip;
4637 			np->nl_realport = nat->nat_odport;
4638 		}
4639  	}
4640 
4641 	return nat;
4642 }
4643 
4644 
4645 /* ------------------------------------------------------------------------ */
4646 /* Function:    ipf_nat_match                                               */
4647 /* Returns:     int - 0 == no match, 1 == match                             */
4648 /* Parameters:  fin(I)   - pointer to packet information                    */
4649 /*              np(I)    - pointer to NAT rule                              */
4650 /*                                                                          */
4651 /* Pull the matching of a packet against a NAT rule out of that complex     */
4652 /* loop inside ipf_nat_checkin() and lay it out properly in its own function. */
4653 /* ------------------------------------------------------------------------ */
4654 static int
ipf_nat_match(fr_info_t * fin,ipnat_t * np)4655 ipf_nat_match(fr_info_t *fin, ipnat_t *np)
4656 {
4657 	ipf_main_softc_t *softc = fin->fin_main_soft;
4658 	frtuc_t *ft;
4659 	int match;
4660 
4661 	match = 0;
4662 	switch (np->in_osrcatype)
4663 	{
4664 	case FRI_NORMAL :
4665 		match = ((fin->fin_saddr & np->in_osrcmsk) != np->in_osrcaddr);
4666 		break;
4667 	case FRI_LOOKUP :
4668 		match = (*np->in_osrcfunc)(softc, np->in_osrcptr,
4669 					   4, &fin->fin_saddr, fin->fin_plen);
4670 		break;
4671 	}
4672 	match ^= ((np->in_flags & IPN_NOTSRC) != 0);
4673 	if (match)
4674 		return 0;
4675 
4676 	match = 0;
4677 	switch (np->in_odstatype)
4678 	{
4679 	case FRI_NORMAL :
4680 		match = ((fin->fin_daddr & np->in_odstmsk) != np->in_odstaddr);
4681 		break;
4682 	case FRI_LOOKUP :
4683 		match = (*np->in_odstfunc)(softc, np->in_odstptr,
4684 					   4, &fin->fin_daddr, fin->fin_plen);
4685 		break;
4686 	}
4687 
4688 	match ^= ((np->in_flags & IPN_NOTDST) != 0);
4689 	if (match)
4690 		return 0;
4691 
4692 	ft = &np->in_tuc;
4693 	if (!(fin->fin_flx & FI_TCPUDP) ||
4694 	    (fin->fin_flx & (FI_SHORT|FI_FRAGBODY))) {
4695 		if (ft->ftu_scmp || ft->ftu_dcmp)
4696 			return 0;
4697 		return 1;
4698 	}
4699 
4700 	return ipf_tcpudpchk(&fin->fin_fi, ft);
4701 }
4702 
4703 
4704 /* ------------------------------------------------------------------------ */
4705 /* Function:    ipf_nat_update                                              */
4706 /* Returns:     Nil                                                         */
4707 /* Parameters:  fin(I) - pointer to packet information                      */
4708 /*              nat(I) - pointer to NAT structure                           */
4709 /*                                                                          */
4710 /* Updates the lifetime of a NAT table entry for non-TCP packets.  Must be  */
4711 /* called with fin_rev updated - i.e. after calling ipf_nat_proto().        */
4712 /*                                                                          */
4713 /* This *MUST* be called after ipf_nat_proto() as it expects fin_rev to     */
4714 /* already be set.                                                          */
4715 /* ------------------------------------------------------------------------ */
4716 void
ipf_nat_update(fr_info_t * fin,nat_t * nat)4717 ipf_nat_update(fr_info_t *fin, nat_t *nat)
4718 {
4719 	ipf_main_softc_t *softc = fin->fin_main_soft;
4720 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
4721 	ipftq_t *ifq, *ifq2;
4722 	ipftqent_t *tqe;
4723 	ipnat_t *np = nat->nat_ptr;
4724 
4725 	tqe = &nat->nat_tqe;
4726 	ifq = tqe->tqe_ifq;
4727 
4728 	/*
4729 	 * We allow over-riding of NAT timeouts from NAT rules, even for
4730 	 * TCP, however, if it is TCP and there is no rule timeout set,
4731 	 * then do not update the timeout here.
4732 	 */
4733 	if (np != NULL) {
4734 		np->in_bytes[fin->fin_rev] += fin->fin_plen;
4735 		ifq2 = np->in_tqehead[fin->fin_rev];
4736 	} else {
4737 		ifq2 = NULL;
4738 	}
4739 
4740 	if (nat->nat_pr[0] == IPPROTO_TCP && ifq2 == NULL) {
4741 		(void) ipf_tcp_age(&nat->nat_tqe, fin, softn->ipf_nat_tcptq,
4742 				   0, 2);
4743 	} else {
4744 		if (ifq2 == NULL) {
4745 			if (nat->nat_pr[0] == IPPROTO_UDP)
4746 				ifq2 = fin->fin_rev ? &softn->ipf_nat_udpacktq :
4747 						      &softn->ipf_nat_udptq;
4748 			else if (nat->nat_pr[0] == IPPROTO_ICMP ||
4749 				 nat->nat_pr[0] == IPPROTO_ICMPV6)
4750 				ifq2 = fin->fin_rev ? &softn->ipf_nat_icmpacktq:
4751 						      &softn->ipf_nat_icmptq;
4752 			else
4753 				ifq2 = &softn->ipf_nat_iptq;
4754 		}
4755 
4756 		ipf_movequeue(softc->ipf_ticks, tqe, ifq, ifq2);
4757 	}
4758 }
4759 
4760 
4761 /* ------------------------------------------------------------------------ */
4762 /* Function:    ipf_nat_checkout                                            */
4763 /* Returns:     int - -1 == packet failed NAT checks so block it,           */
4764 /*                     0 == no packet translation occurred,                 */
4765 /*                     1 == packet was successfully translated.             */
4766 /* Parameters:  fin(I)   - pointer to packet information                    */
4767 /*              passp(I) - pointer to filtering result flags                */
4768 /*                                                                          */
4769 /* Check to see if an outcoming packet should be changed.  ICMP packets are */
4770 /* first checked to see if they match an existing entry (if an error),      */
4771 /* otherwise a search of the current NAT table is made.  If neither results */
4772 /* in a match then a search for a matching NAT rule is made.  Create a new  */
4773 /* NAT entry if a we matched a NAT rule.  Lastly, actually change the       */
4774 /* packet header(s) as required.                                            */
4775 /* ------------------------------------------------------------------------ */
4776 int
ipf_nat_checkout(fr_info_t * fin,u_32_t * passp)4777 ipf_nat_checkout(fr_info_t *fin, u_32_t *passp)
4778 {
4779 	ipnat_t *np = NULL, *npnext;
4780 	struct ifnet *ifp, *sifp;
4781 	ipf_main_softc_t *softc;
4782 	ipf_nat_softc_t *softn;
4783 	tcphdr_t *tcp = NULL;
4784 	int rval, natfailed;
4785 	u_int nflags = 0;
4786 	u_32_t ipa, iph;
4787 	int natadd = 1;
4788 	frentry_t *fr;
4789 	nat_t *nat;
4790 
4791 	if (fin->fin_v == 6) {
4792 #ifdef USE_INET6
4793 		return ipf_nat6_checkout(fin, passp);
4794 #else
4795 		return 0;
4796 #endif
4797 	}
4798 
4799 	softc = fin->fin_main_soft;
4800 	softn = softc->ipf_nat_soft;
4801 
4802 	if (softn->ipf_nat_lock != 0)
4803 		return 0;
4804 	if (softn->ipf_nat_stats.ns_rules == 0 &&
4805 	    softn->ipf_nat_instances == NULL)
4806 		return 0;
4807 
4808 	natfailed = 0;
4809 	fr = fin->fin_fr;
4810 	sifp = fin->fin_ifp;
4811 	if (fr != NULL) {
4812 		ifp = fr->fr_tifs[fin->fin_rev].fd_ptr;
4813 		if ((ifp != NULL) && (ifp != (void *)-1))
4814 			fin->fin_ifp = ifp;
4815 	}
4816 	ifp = fin->fin_ifp;
4817 
4818 	if (!(fin->fin_flx & FI_SHORT) && (fin->fin_off == 0)) {
4819 		switch (fin->fin_p)
4820 		{
4821 		case IPPROTO_TCP :
4822 			nflags = IPN_TCP;
4823 			break;
4824 		case IPPROTO_UDP :
4825 			nflags = IPN_UDP;
4826 			break;
4827 		case IPPROTO_ICMP :
4828 			/*
4829 			 * This is an incoming packet, so the destination is
4830 			 * the icmp_id and the source port equals 0
4831 			 */
4832 			if ((fin->fin_flx & FI_ICMPQUERY) != 0)
4833 				nflags = IPN_ICMPQUERY;
4834 			break;
4835 		default :
4836 			break;
4837 		}
4838 
4839 		if ((nflags & IPN_TCPUDP))
4840 			tcp = fin->fin_dp;
4841 	}
4842 
4843 	ipa = fin->fin_saddr;
4844 
4845 	READ_ENTER(&softc->ipf_nat);
4846 
4847 	if ((fin->fin_p == IPPROTO_ICMP) && !(nflags & IPN_ICMPQUERY) &&
4848 	    (nat = ipf_nat_icmperror(fin, &nflags, NAT_OUTBOUND)))
4849 		/*EMPTY*/;
4850 	else if ((fin->fin_flx & FI_FRAG) && (nat = ipf_frag_natknown(fin)))
4851 		natadd = 0;
4852 	else if ((nat = ipf_nat_outlookup(fin, nflags|NAT_SEARCH,
4853 				      (u_int)fin->fin_p, fin->fin_src,
4854 				      fin->fin_dst))) {
4855 		nflags = nat->nat_flags;
4856 	} else if (fin->fin_off == 0) {
4857 		u_32_t hv, msk, nmsk = 0;
4858 
4859 		/*
4860 		 * If there is no current entry in the nat table for this IP#,
4861 		 * create one for it (if there is a matching rule).
4862 		 */
4863 maskloop:
4864 		msk = softn->ipf_nat_map_active_masks[nmsk];
4865 		iph = ipa & msk;
4866 		hv = NAT_HASH_FN(iph, 0, softn->ipf_nat_maprules_sz);
4867 retry_roundrobin:
4868 		for (np = softn->ipf_nat_map_rules[hv]; np; np = npnext) {
4869 			npnext = np->in_mnext;
4870 			if ((np->in_ifps[1] && (np->in_ifps[1] != ifp)))
4871 				continue;
4872 			if (np->in_v[0] != 4)
4873 				continue;
4874 			if (np->in_pr[1] && (np->in_pr[1] != fin->fin_p))
4875 				continue;
4876 			if ((np->in_flags & IPN_RF) &&
4877 			    !(np->in_flags & nflags))
4878 				continue;
4879 			if (np->in_flags & IPN_FILTER) {
4880 				switch (ipf_nat_match(fin, np))
4881 				{
4882 				case 0 :
4883 					continue;
4884 				case -1 :
4885 					rval = -1;
4886 					goto outmatchfail;
4887 				case 1 :
4888 				default :
4889 					break;
4890 				}
4891 			} else if ((ipa & np->in_osrcmsk) != np->in_osrcaddr)
4892 				continue;
4893 
4894 			if ((fr != NULL) &&
4895 			    !ipf_matchtag(&np->in_tag, &fr->fr_nattag))
4896 				continue;
4897 
4898 			if (np->in_plabel != -1) {
4899 				if (((np->in_flags & IPN_FILTER) == 0) &&
4900 				    (np->in_odport != fin->fin_data[1]))
4901 					continue;
4902 				if (ipf_proxy_ok(fin, tcp, np) == 0)
4903 					continue;
4904 			}
4905 
4906 			if (np->in_flags & IPN_NO) {
4907 				np->in_hits++;
4908 				break;
4909 			}
4910 			MUTEX_ENTER(&softn->ipf_nat_new);
4911 			/*
4912 			 * If we've matched a round-robin rule but it has
4913 			 * moved in the list since we got it, start over as
4914 			 * this is now no longer correct.
4915 			 */
4916 			if (npnext != np->in_mnext) {
4917 				if ((np->in_flags & IPN_ROUNDR) != 0) {
4918 					MUTEX_EXIT(&softn->ipf_nat_new);
4919 					goto retry_roundrobin;
4920 				}
4921 				npnext = np->in_mnext;
4922 			}
4923 
4924 			nat = ipf_nat_add(fin, np, NULL, nflags, NAT_OUTBOUND);
4925 			MUTEX_EXIT(&softn->ipf_nat_new);
4926 			if (nat != NULL) {
4927 				natfailed = 0;
4928 				break;
4929 			}
4930 			natfailed = -1;
4931 		}
4932 		if ((np == NULL) && (nmsk < softn->ipf_nat_map_max)) {
4933 			nmsk++;
4934 			goto maskloop;
4935 		}
4936 	}
4937 
4938 	if (nat != NULL) {
4939 		rval = ipf_nat_out(fin, nat, natadd, nflags);
4940 		if (rval == 1) {
4941 			MUTEX_ENTER(&nat->nat_lock);
4942 			ipf_nat_update(fin, nat);
4943 			nat->nat_bytes[1] += fin->fin_plen;
4944 			nat->nat_pkts[1]++;
4945 			fin->fin_pktnum = nat->nat_pkts[1];
4946 			MUTEX_EXIT(&nat->nat_lock);
4947 		}
4948 	} else
4949 		rval = natfailed;
4950 outmatchfail:
4951 	RWLOCK_EXIT(&softc->ipf_nat);
4952 
4953 	switch (rval)
4954 	{
4955 	case -1 :
4956 		if (passp != NULL) {
4957 			DT1(frb_natv4out, fr_info_t *, fin);
4958 			NBUMPSIDED(1, ns_drop);
4959 			*passp = FR_BLOCK;
4960 			fin->fin_reason = FRB_NATV4;
4961 		}
4962 		fin->fin_flx |= FI_BADNAT;
4963 		NBUMPSIDED(1, ns_badnat);
4964 		break;
4965 	case 0 :
4966 		NBUMPSIDE(1, ns_ignored);
4967 		break;
4968 	case 1 :
4969 		NBUMPSIDE(1, ns_translated);
4970 		break;
4971 	}
4972 	fin->fin_ifp = sifp;
4973 	return rval;
4974 }
4975 
4976 /* ------------------------------------------------------------------------ */
4977 /* Function:    ipf_nat_out                                                 */
4978 /* Returns:     int - -1 == packet failed NAT checks so block it,           */
4979 /*                     1 == packet was successfully translated.             */
4980 /* Parameters:  fin(I)    - pointer to packet information                   */
4981 /*              nat(I)    - pointer to NAT structure                        */
4982 /*              natadd(I) - flag indicating if it is safe to add frag cache */
4983 /*              nflags(I) - NAT flags set for this packet                   */
4984 /*                                                                          */
4985 /* Translate a packet coming "out" on an interface.                         */
4986 /* ------------------------------------------------------------------------ */
4987 int
ipf_nat_out(fr_info_t * fin,nat_t * nat,int natadd,u_32_t nflags)4988 ipf_nat_out(fr_info_t *fin, nat_t *nat, int natadd, u_32_t nflags)
4989 {
4990 	ipf_main_softc_t *softc = fin->fin_main_soft;
4991 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
4992 	icmphdr_t *icmp;
4993 	tcphdr_t *tcp;
4994 	ipnat_t *np;
4995 	int skip;
4996 	int i;
4997 
4998 	tcp = NULL;
4999 	icmp = NULL;
5000 	np = nat->nat_ptr;
5001 
5002 	if ((natadd != 0) && (fin->fin_flx & FI_FRAG) && (np != NULL))
5003 		(void) ipf_frag_natnew(softc, fin, 0, nat);
5004 
5005 	/*
5006 	 * Fix up checksums, not by recalculating them, but
5007 	 * simply computing adjustments.
5008 	 * This is only done for STREAMS based IP implementations where the
5009 	 * checksum has already been calculated by IP.  In all other cases,
5010 	 * IPFilter is called before the checksum needs calculating so there
5011 	 * is no call to modify whatever is in the header now.
5012 	 */
5013 	if (nflags == IPN_ICMPERR) {
5014 		u_32_t s1, s2, sumd, msumd;
5015 
5016 		s1 = LONG_SUM(ntohl(fin->fin_saddr));
5017 		if (nat->nat_dir == NAT_OUTBOUND) {
5018 			s2 = LONG_SUM(ntohl(nat->nat_nsrcaddr));
5019 		} else {
5020 			s2 = LONG_SUM(ntohl(nat->nat_odstaddr));
5021 		}
5022 		CALC_SUMD(s1, s2, sumd);
5023 		msumd = sumd;
5024 
5025 		s1 = LONG_SUM(ntohl(fin->fin_daddr));
5026 		if (nat->nat_dir == NAT_OUTBOUND) {
5027 			s2 = LONG_SUM(ntohl(nat->nat_ndstaddr));
5028 		} else {
5029 			s2 = LONG_SUM(ntohl(nat->nat_osrcaddr));
5030 		}
5031 		CALC_SUMD(s1, s2, sumd);
5032 		msumd += sumd;
5033 
5034 		ipf_fix_outcksum(0, &fin->fin_ip->ip_sum, msumd, 0);
5035 	}
5036 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) || \
5037     defined(linux)
5038 	else {
5039 		/*
5040 		 * Strictly speaking, this isn't necessary on BSD
5041 		 * kernels because they do checksum calculation after
5042 		 * this code has run BUT if ipfilter is being used
5043 		 * to do NAT as a bridge, that code doesn't exist.
5044 		 */
5045 		switch (nat->nat_dir)
5046 		{
5047 		case NAT_OUTBOUND :
5048 			ipf_fix_outcksum(fin->fin_cksum & FI_CK_L4PART,
5049 					 &fin->fin_ip->ip_sum,
5050 					 nat->nat_ipsumd, 0);
5051 			break;
5052 
5053 		case NAT_INBOUND :
5054 			ipf_fix_incksum(fin->fin_cksum & FI_CK_L4PART,
5055 					&fin->fin_ip->ip_sum,
5056 					nat->nat_ipsumd, 0);
5057 			break;
5058 
5059 		default :
5060 			break;
5061 		}
5062 	}
5063 #endif
5064 
5065 	/*
5066 	 * Address assignment is after the checksum modification because
5067 	 * we are using the address in the packet for determining the
5068 	 * correct checksum offset (the ICMP error could be coming from
5069 	 * anyone...)
5070 	 */
5071 	switch (nat->nat_dir)
5072 	{
5073 	case NAT_OUTBOUND :
5074 		fin->fin_ip->ip_src = nat->nat_nsrcip;
5075 		fin->fin_saddr = nat->nat_nsrcaddr;
5076 		fin->fin_ip->ip_dst = nat->nat_ndstip;
5077 		fin->fin_daddr = nat->nat_ndstaddr;
5078 		break;
5079 
5080 	case NAT_INBOUND :
5081 		fin->fin_ip->ip_src = nat->nat_odstip;
5082 		fin->fin_saddr = nat->nat_ndstaddr;
5083 		fin->fin_ip->ip_dst = nat->nat_osrcip;
5084 		fin->fin_daddr = nat->nat_nsrcaddr;
5085 		break;
5086 
5087 	case NAT_DIVERTIN :
5088 	    {
5089 		mb_t *m;
5090 
5091 		skip = ipf_nat_decap(fin, nat);
5092 		if (skip <= 0) {
5093 			NBUMPSIDED(1, ns_decap_fail);
5094 			return -1;
5095 		}
5096 
5097 		m = fin->fin_m;
5098 
5099 #if defined(MENTAT) && defined(_KERNEL)
5100 		m->b_rptr += skip;
5101 #else
5102 		m->m_data += skip;
5103 		m->m_len -= skip;
5104 
5105 # ifdef M_PKTHDR
5106 		if (m->m_flags & M_PKTHDR)
5107 			m->m_pkthdr.len -= skip;
5108 # endif
5109 #endif
5110 
5111 		MUTEX_ENTER(&nat->nat_lock);
5112 		ipf_nat_update(fin, nat);
5113 		MUTEX_EXIT(&nat->nat_lock);
5114 		fin->fin_flx |= FI_NATED;
5115 		if (np != NULL && np->in_tag.ipt_num[0] != 0)
5116 			fin->fin_nattag = &np->in_tag;
5117 		return 1;
5118 		/* NOTREACHED */
5119 	    }
5120 
5121 	case NAT_DIVERTOUT :
5122 	    {
5123 		u_32_t s1, s2, sumd;
5124 		udphdr_t *uh;
5125 		ip_t *ip;
5126 		mb_t *m;
5127 
5128 		m = M_DUP(np->in_divmp);
5129 		if (m == NULL) {
5130 			NBUMPSIDED(1, ns_divert_dup);
5131 			return -1;
5132 		}
5133 
5134 		ip = MTOD(m, ip_t *);
5135 		ip->ip_id = htons(ipf_nextipid(fin));
5136 		s2 = ntohs(ip->ip_id);
5137 
5138 		s1 = ip->ip_len;
5139 		ip->ip_len = ntohs(ip->ip_len);
5140 		ip->ip_len += fin->fin_plen;
5141 		ip->ip_len = htons(ip->ip_len);
5142 		s2 += ntohs(ip->ip_len);
5143 		CALC_SUMD(s1, s2, sumd);
5144 
5145 		uh = (udphdr_t *)(ip + 1);
5146 		uh->uh_ulen += fin->fin_plen;
5147 		uh->uh_ulen = htons(uh->uh_ulen);
5148 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) || \
5149     defined(linux)
5150 		ipf_fix_outcksum(0, &ip->ip_sum, sumd, 0);
5151 #endif
5152 
5153 		PREP_MB_T(fin, m);
5154 
5155 		fin->fin_src = ip->ip_src;
5156 		fin->fin_dst = ip->ip_dst;
5157 		fin->fin_ip = ip;
5158 		fin->fin_plen += sizeof(ip_t) + 8;	/* UDP + IPv4 hdr */
5159 		fin->fin_dlen += sizeof(ip_t) + 8;	/* UDP + IPv4 hdr */
5160 
5161 		nflags &= ~IPN_TCPUDPICMP;
5162 
5163 		break;
5164 	    }
5165 
5166 	default :
5167 		break;
5168 	}
5169 
5170 	if (!(fin->fin_flx & FI_SHORT) && (fin->fin_off == 0)) {
5171 		u_short *csump;
5172 
5173 		if ((nat->nat_nsport != 0) && (nflags & IPN_TCPUDP)) {
5174 			tcp = fin->fin_dp;
5175 
5176 			switch (nat->nat_dir)
5177 			{
5178 			case NAT_OUTBOUND :
5179 				tcp->th_sport = nat->nat_nsport;
5180 				fin->fin_data[0] = ntohs(nat->nat_nsport);
5181 				tcp->th_dport = nat->nat_ndport;
5182 				fin->fin_data[1] = ntohs(nat->nat_ndport);
5183 				break;
5184 
5185 			case NAT_INBOUND :
5186 				tcp->th_sport = nat->nat_odport;
5187 				fin->fin_data[0] = ntohs(nat->nat_odport);
5188 				tcp->th_dport = nat->nat_osport;
5189 				fin->fin_data[1] = ntohs(nat->nat_osport);
5190 				break;
5191 			}
5192 		}
5193 
5194 		if ((nat->nat_oicmpid != 0) && (nflags & IPN_ICMPQUERY)) {
5195 			icmp = fin->fin_dp;
5196 
5197 			switch (nat->nat_dir)
5198 			{
5199 			case NAT_OUTBOUND :
5200 				icmp->icmp_id = nat->nat_nicmpid;
5201 				break;
5202 			case NAT_INBOUND :
5203 				icmp->icmp_id = nat->nat_oicmpid;
5204 				break;
5205 			}
5206 		}
5207 
5208 		csump = ipf_nat_proto(fin, nat, nflags);
5209 
5210 		/*
5211 		 * The above comments do not hold for layer 4 (or higher)
5212 		 * checksums...
5213 		 */
5214 		if (csump != NULL) {
5215 			if (nat->nat_dir == NAT_OUTBOUND)
5216 				ipf_fix_outcksum(fin->fin_cksum, csump,
5217 						 nat->nat_sumd[0],
5218 						 nat->nat_sumd[1] +
5219 						 fin->fin_dlen);
5220 			else
5221 				ipf_fix_incksum(fin->fin_cksum, csump,
5222 						nat->nat_sumd[0],
5223 						nat->nat_sumd[1] +
5224 						fin->fin_dlen);
5225 		}
5226 	}
5227 
5228 	ipf_sync_update(softc, SMC_NAT, fin, nat->nat_sync);
5229 	/* ------------------------------------------------------------- */
5230 	/* A few quick notes:                                            */
5231 	/*      Following are test conditions prior to calling the       */
5232 	/*      ipf_proxy_check routine.                                 */
5233 	/*                                                               */
5234 	/*      A NULL tcp indicates a non TCP/UDP packet.  When dealing */
5235 	/*      with a redirect rule, we attempt to match the packet's   */
5236 	/*      source port against in_dport, otherwise we'd compare the */
5237 	/*      packet's destination.                                    */
5238 	/* ------------------------------------------------------------- */
5239 	if ((np != NULL) && (np->in_apr != NULL)) {
5240 		i = ipf_proxy_check(fin, nat);
5241 		if (i == 0) {
5242 			i = 1;
5243 		} else if (i == -1) {
5244 			NBUMPSIDED(1, ns_ipf_proxy_fail);
5245 		}
5246 	} else {
5247 		i = 1;
5248 	}
5249 	fin->fin_flx |= FI_NATED;
5250 	return i;
5251 }
5252 
5253 
5254 /* ------------------------------------------------------------------------ */
5255 /* Function:    ipf_nat_checkin                                             */
5256 /* Returns:     int - -1 == packet failed NAT checks so block it,           */
5257 /*                     0 == no packet translation occurred,                 */
5258 /*                     1 == packet was successfully translated.             */
5259 /* Parameters:  fin(I)   - pointer to packet information                    */
5260 /*              passp(I) - pointer to filtering result flags                */
5261 /*                                                                          */
5262 /* Check to see if an incoming packet should be changed.  ICMP packets are  */
5263 /* first checked to see if they match an existing entry (if an error),      */
5264 /* otherwise a search of the current NAT table is made.  If neither results */
5265 /* in a match then a search for a matching NAT rule is made.  Create a new  */
5266 /* NAT entry if a we matched a NAT rule.  Lastly, actually change the       */
5267 /* packet header(s) as required.                                            */
5268 /* ------------------------------------------------------------------------ */
5269 int
ipf_nat_checkin(fr_info_t * fin,u_32_t * passp)5270 ipf_nat_checkin(fr_info_t *fin, u_32_t *passp)
5271 {
5272 	ipf_main_softc_t *softc;
5273 	ipf_nat_softc_t *softn;
5274 	u_int nflags, natadd;
5275 	ipnat_t *np, *npnext;
5276 	int rval, natfailed;
5277 	struct ifnet *ifp;
5278 	struct in_addr in;
5279 	icmphdr_t *icmp;
5280 	tcphdr_t *tcp;
5281 	u_short dport;
5282 	nat_t *nat;
5283 	u_32_t iph;
5284 
5285 	softc = fin->fin_main_soft;
5286 	softn = softc->ipf_nat_soft;
5287 
5288 	if (softn->ipf_nat_lock != 0)
5289 		return 0;
5290 	if (softn->ipf_nat_stats.ns_rules == 0 &&
5291 	    softn->ipf_nat_instances == NULL)
5292 		return 0;
5293 
5294 	tcp = NULL;
5295 	icmp = NULL;
5296 	dport = 0;
5297 	natadd = 1;
5298 	nflags = 0;
5299 	natfailed = 0;
5300 	ifp = fin->fin_ifp;
5301 
5302 	if (!(fin->fin_flx & FI_SHORT) && (fin->fin_off == 0)) {
5303 		switch (fin->fin_p)
5304 		{
5305 		case IPPROTO_TCP :
5306 			nflags = IPN_TCP;
5307 			break;
5308 		case IPPROTO_UDP :
5309 			nflags = IPN_UDP;
5310 			break;
5311 		case IPPROTO_ICMP :
5312 			icmp = fin->fin_dp;
5313 
5314 			/*
5315 			 * This is an incoming packet, so the destination is
5316 			 * the icmp_id and the source port equals 0
5317 			 */
5318 			if ((fin->fin_flx & FI_ICMPQUERY) != 0) {
5319 				nflags = IPN_ICMPQUERY;
5320 				dport = icmp->icmp_id;
5321 			} break;
5322 		default :
5323 			break;
5324 		}
5325 
5326 		if ((nflags & IPN_TCPUDP)) {
5327 			tcp = fin->fin_dp;
5328 			dport = fin->fin_data[1];
5329 		}
5330 	}
5331 
5332 	in = fin->fin_dst;
5333 
5334 	READ_ENTER(&softc->ipf_nat);
5335 
5336 	if ((fin->fin_p == IPPROTO_ICMP) && !(nflags & IPN_ICMPQUERY) &&
5337 	    (nat = ipf_nat_icmperror(fin, &nflags, NAT_INBOUND)))
5338 		/*EMPTY*/;
5339 	else if ((fin->fin_flx & FI_FRAG) && (nat = ipf_frag_natknown(fin)))
5340 		natadd = 0;
5341 	else if ((nat = ipf_nat_inlookup(fin, nflags|NAT_SEARCH,
5342 					 (u_int)fin->fin_p,
5343 					 fin->fin_src, in))) {
5344 		nflags = nat->nat_flags;
5345 	} else if (fin->fin_off == 0) {
5346 		u_32_t hv, msk, rmsk = 0;
5347 
5348 		/*
5349 		 * If there is no current entry in the nat table for this IP#,
5350 		 * create one for it (if there is a matching rule).
5351 		 */
5352 maskloop:
5353 		msk = softn->ipf_nat_rdr_active_masks[rmsk];
5354 		iph = in.s_addr & msk;
5355 		hv = NAT_HASH_FN(iph, 0, softn->ipf_nat_rdrrules_sz);
5356 retry_roundrobin:
5357 		/* TRACE (iph,msk,rmsk,hv,softn->ipf_nat_rdrrules_sz) */
5358 		for (np = softn->ipf_nat_rdr_rules[hv]; np; np = npnext) {
5359 			npnext = np->in_rnext;
5360 			if (np->in_ifps[0] && (np->in_ifps[0] != ifp))
5361 				continue;
5362 			if (np->in_v[0] != 4)
5363 				continue;
5364 			if (np->in_pr[0] && (np->in_pr[0] != fin->fin_p))
5365 				continue;
5366 			if ((np->in_flags & IPN_RF) && !(np->in_flags & nflags))
5367 				continue;
5368 			if (np->in_flags & IPN_FILTER) {
5369 				switch (ipf_nat_match(fin, np))
5370 				{
5371 				case 0 :
5372 					continue;
5373 				case -1 :
5374 					rval = -1;
5375 					goto inmatchfail;
5376 				case 1 :
5377 				default :
5378 					break;
5379 				}
5380 			} else {
5381 				if ((in.s_addr & np->in_odstmsk) !=
5382 				    np->in_odstaddr)
5383 					continue;
5384 				if (np->in_odport &&
5385 				    ((np->in_dtop < dport) ||
5386 				     (dport < np->in_odport)))
5387 					continue;
5388 			}
5389 
5390 			if (np->in_plabel != -1) {
5391 				if (!ipf_proxy_ok(fin, tcp, np)) {
5392 					continue;
5393 				}
5394 			}
5395 
5396 			if (np->in_flags & IPN_NO) {
5397 				np->in_hits++;
5398 				break;
5399 			}
5400 
5401 			MUTEX_ENTER(&softn->ipf_nat_new);
5402 			/*
5403 			 * If we've matched a round-robin rule but it has
5404 			 * moved in the list since we got it, start over as
5405 			 * this is now no longer correct.
5406 			 */
5407 			if (npnext != np->in_rnext) {
5408 				if ((np->in_flags & IPN_ROUNDR) != 0) {
5409 					MUTEX_EXIT(&softn->ipf_nat_new);
5410 					goto retry_roundrobin;
5411 				}
5412 				npnext = np->in_rnext;
5413 			}
5414 
5415 			nat = ipf_nat_add(fin, np, NULL, nflags, NAT_INBOUND);
5416 			MUTEX_EXIT(&softn->ipf_nat_new);
5417 			if (nat != NULL) {
5418 				natfailed = 0;
5419 				break;
5420 			}
5421 			natfailed = -1;
5422 		}
5423 		if ((np == NULL) && (rmsk < softn->ipf_nat_rdr_max)) {
5424 			rmsk++;
5425 			goto maskloop;
5426 		}
5427 	}
5428 
5429 	if (nat != NULL) {
5430 		rval = ipf_nat_in(fin, nat, natadd, nflags);
5431 		if (rval == 1) {
5432 			MUTEX_ENTER(&nat->nat_lock);
5433 			ipf_nat_update(fin, nat);
5434 			nat->nat_bytes[0] += fin->fin_plen;
5435 			nat->nat_pkts[0]++;
5436 			fin->fin_pktnum = nat->nat_pkts[0];
5437 			MUTEX_EXIT(&nat->nat_lock);
5438 		}
5439 	} else
5440 		rval = natfailed;
5441 inmatchfail:
5442 	RWLOCK_EXIT(&softc->ipf_nat);
5443 
5444 	switch (rval)
5445 	{
5446 	case -1 :
5447 		if (passp != NULL) {
5448 			DT1(frb_natv4in, fr_info_t *, fin);
5449 			NBUMPSIDED(0, ns_drop);
5450 			*passp = FR_BLOCK;
5451 			fin->fin_reason = FRB_NATV4;
5452 		}
5453 		fin->fin_flx |= FI_BADNAT;
5454 		NBUMPSIDED(0, ns_badnat);
5455 		break;
5456 	case 0 :
5457 		NBUMPSIDE(0, ns_ignored);
5458 		break;
5459 	case 1 :
5460 		NBUMPSIDE(0, ns_translated);
5461 		break;
5462 	}
5463 	return rval;
5464 }
5465 
5466 
5467 /* ------------------------------------------------------------------------ */
5468 /* Function:    ipf_nat_in                                                  */
5469 /* Returns:     int - -1 == packet failed NAT checks so block it,           */
5470 /*                     1 == packet was successfully translated.             */
5471 /* Parameters:  fin(I)    - pointer to packet information                   */
5472 /*              nat(I)    - pointer to NAT structure                        */
5473 /*              natadd(I) - flag indicating if it is safe to add frag cache */
5474 /*              nflags(I) - NAT flags set for this packet                   */
5475 /* Locks Held:  ipf_nat(READ)                                               */
5476 /*                                                                          */
5477 /* Translate a packet coming "in" on an interface.                          */
5478 /* ------------------------------------------------------------------------ */
5479 int
ipf_nat_in(fr_info_t * fin,nat_t * nat,int natadd,u_32_t nflags)5480 ipf_nat_in(fr_info_t *fin, nat_t *nat, int natadd, u_32_t nflags)
5481 {
5482 	ipf_main_softc_t *softc = fin->fin_main_soft;
5483 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
5484 	u_32_t sumd, ipsumd, sum1, sum2;
5485 	icmphdr_t *icmp;
5486 	tcphdr_t *tcp;
5487 	ipnat_t *np;
5488 	int skip;
5489 	int i;
5490 
5491 	tcp = NULL;
5492 	np = nat->nat_ptr;
5493 	fin->fin_fr = nat->nat_fr;
5494 
5495 	if (np != NULL) {
5496 		if ((natadd != 0) && (fin->fin_flx & FI_FRAG))
5497 			(void) ipf_frag_natnew(softc, fin, 0, nat);
5498 
5499 	/* ------------------------------------------------------------- */
5500 	/* A few quick notes:                                            */
5501 	/*      Following are test conditions prior to calling the       */
5502 	/*      ipf_proxy_check routine.                                 */
5503 	/*                                                               */
5504 	/*      A NULL tcp indicates a non TCP/UDP packet.  When dealing */
5505 	/*      with a map rule, we attempt to match the packet's        */
5506 	/*      source port against in_dport, otherwise we'd compare the */
5507 	/*      packet's destination.                                    */
5508 	/* ------------------------------------------------------------- */
5509 		if (np->in_apr != NULL) {
5510 			i = ipf_proxy_check(fin, nat);
5511 			if (i == -1) {
5512 				NBUMPSIDED(0, ns_ipf_proxy_fail);
5513 				return -1;
5514 			}
5515 		}
5516 	}
5517 
5518 	ipf_sync_update(softc, SMC_NAT, fin, nat->nat_sync);
5519 
5520 	ipsumd = nat->nat_ipsumd;
5521 	/*
5522 	 * Fix up checksums, not by recalculating them, but
5523 	 * simply computing adjustments.
5524 	 * Why only do this for some platforms on inbound packets ?
5525 	 * Because for those that it is done, IP processing is yet to happen
5526 	 * and so the IPv4 header checksum has not yet been evaluated.
5527 	 * Perhaps it should always be done for the benefit of things like
5528 	 * fast forwarding (so that it doesn't need to be recomputed) but with
5529 	 * header checksum offloading, perhaps it is a moot point.
5530 	 */
5531 
5532 	switch (nat->nat_dir)
5533 	{
5534 	case NAT_INBOUND :
5535 		if ((fin->fin_flx & FI_ICMPERR) == 0) {
5536 			fin->fin_ip->ip_src = nat->nat_nsrcip;
5537 			fin->fin_saddr = nat->nat_nsrcaddr;
5538 		} else {
5539 			sum1 = nat->nat_osrcaddr;
5540 			sum2 = nat->nat_nsrcaddr;
5541 			CALC_SUMD(sum1, sum2, sumd);
5542 			ipsumd -= sumd;
5543 		}
5544 		fin->fin_ip->ip_dst = nat->nat_ndstip;
5545 		fin->fin_daddr = nat->nat_ndstaddr;
5546 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) || \
5547      defined(__osf__) || defined(linux)
5548 		ipf_fix_outcksum(0, &fin->fin_ip->ip_sum, ipsumd, 0);
5549 #endif
5550 		break;
5551 
5552 	case NAT_OUTBOUND :
5553 		if ((fin->fin_flx & FI_ICMPERR) == 0) {
5554 			fin->fin_ip->ip_src = nat->nat_odstip;
5555 			fin->fin_saddr = nat->nat_odstaddr;
5556 		} else {
5557 			sum1 = nat->nat_odstaddr;
5558 			sum2 = nat->nat_ndstaddr;
5559 			CALC_SUMD(sum1, sum2, sumd);
5560 			ipsumd -= sumd;
5561 		}
5562 		fin->fin_ip->ip_dst = nat->nat_osrcip;
5563 		fin->fin_daddr = nat->nat_osrcaddr;
5564 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) || \
5565      defined(__osf__) || defined(linux)
5566 		ipf_fix_incksum(0, &fin->fin_ip->ip_sum, ipsumd, 0);
5567 #endif
5568 		break;
5569 
5570 	case NAT_DIVERTIN :
5571 	    {
5572 		udphdr_t *uh;
5573 		ip_t *ip;
5574 		mb_t *m;
5575 
5576 		m = M_DUP(np->in_divmp);
5577 		if (m == NULL) {
5578 			NBUMPSIDED(0, ns_divert_dup);
5579 			return -1;
5580 		}
5581 
5582 		ip = MTOD(m, ip_t *);
5583 		ip->ip_id = htons(ipf_nextipid(fin));
5584 		sum1 = ntohs(ip->ip_len);
5585 		ip->ip_len = ntohs(ip->ip_len);
5586 		ip->ip_len += fin->fin_plen;
5587 		ip->ip_len = htons(ip->ip_len);
5588 
5589 		uh = (udphdr_t *)(ip + 1);
5590 		uh->uh_ulen += fin->fin_plen;
5591 		uh->uh_ulen = htons(uh->uh_ulen);
5592 
5593 		sum2 = ntohs(ip->ip_id) + ntohs(ip->ip_len);
5594 		sum2 += ntohs(ip->ip_off) & IP_DF;
5595 		CALC_SUMD(sum1, sum2, sumd);
5596 
5597 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) || \
5598      defined(__osf__) || defined(linux)
5599 		ipf_fix_outcksum(0, &ip->ip_sum, sumd, 0);
5600 #endif
5601 		PREP_MB_T(fin, m);
5602 
5603 		fin->fin_ip = ip;
5604 		fin->fin_plen += sizeof(ip_t) + 8;	/* UDP + new IPv4 hdr */
5605 		fin->fin_dlen += sizeof(ip_t) + 8;	/* UDP + old IPv4 hdr */
5606 
5607 		nflags &= ~IPN_TCPUDPICMP;
5608 
5609 		break;
5610 	    }
5611 
5612 	case NAT_DIVERTOUT :
5613 	    {
5614 		mb_t *m;
5615 
5616 		skip = ipf_nat_decap(fin, nat);
5617 		if (skip <= 0) {
5618 			NBUMPSIDED(0, ns_decap_fail);
5619 			return -1;
5620 		}
5621 
5622 		m = fin->fin_m;
5623 
5624 #if defined(MENTAT) && defined(_KERNEL)
5625 		m->b_rptr += skip;
5626 #else
5627 		m->m_data += skip;
5628 		m->m_len -= skip;
5629 
5630 # ifdef M_PKTHDR
5631 		if (m->m_flags & M_PKTHDR)
5632 			m->m_pkthdr.len -= skip;
5633 # endif
5634 #endif
5635 
5636 		ipf_nat_update(fin, nat);
5637 		nflags &= ~IPN_TCPUDPICMP;
5638 		fin->fin_flx |= FI_NATED;
5639 		if (np != NULL && np->in_tag.ipt_num[0] != 0)
5640 			fin->fin_nattag = &np->in_tag;
5641 		return 1;
5642 		/* NOTREACHED */
5643 	    }
5644 	}
5645 	if (nflags & IPN_TCPUDP)
5646 		tcp = fin->fin_dp;
5647 
5648 	if (!(fin->fin_flx & FI_SHORT) && (fin->fin_off == 0)) {
5649 		u_short *csump;
5650 
5651 		if ((nat->nat_odport != 0) && (nflags & IPN_TCPUDP)) {
5652 			switch (nat->nat_dir)
5653 			{
5654 			case NAT_INBOUND :
5655 				tcp->th_sport = nat->nat_nsport;
5656 				fin->fin_data[0] = ntohs(nat->nat_nsport);
5657 				tcp->th_dport = nat->nat_ndport;
5658 				fin->fin_data[1] = ntohs(nat->nat_ndport);
5659 				break;
5660 
5661 			case NAT_OUTBOUND :
5662 				tcp->th_sport = nat->nat_odport;
5663 				fin->fin_data[0] = ntohs(nat->nat_odport);
5664 				tcp->th_dport = nat->nat_osport;
5665 				fin->fin_data[1] = ntohs(nat->nat_osport);
5666 				break;
5667 			}
5668 		}
5669 
5670 
5671 		if ((nat->nat_oicmpid != 0) && (nflags & IPN_ICMPQUERY)) {
5672 			icmp = fin->fin_dp;
5673 
5674 			switch (nat->nat_dir)
5675 			{
5676 			case NAT_INBOUND :
5677 				icmp->icmp_id = nat->nat_nicmpid;
5678 				break;
5679 			case NAT_OUTBOUND :
5680 				icmp->icmp_id = nat->nat_oicmpid;
5681 				break;
5682 			}
5683 		}
5684 
5685 		csump = ipf_nat_proto(fin, nat, nflags);
5686 
5687 		/*
5688 		 * The above comments do not hold for layer 4 (or higher)
5689 		 * checksums...
5690 		 */
5691 		if (csump != NULL) {
5692 			if (nat->nat_dir == NAT_OUTBOUND)
5693 				ipf_fix_incksum(0, csump, nat->nat_sumd[0], 0);
5694 			else
5695 				ipf_fix_outcksum(0, csump, nat->nat_sumd[0], 0);
5696 		}
5697 	}
5698 
5699 	fin->fin_flx |= FI_NATED;
5700 	if (np != NULL && np->in_tag.ipt_num[0] != 0)
5701 		fin->fin_nattag = &np->in_tag;
5702 	return 1;
5703 }
5704 
5705 
5706 /* ------------------------------------------------------------------------ */
5707 /* Function:    ipf_nat_proto                                               */
5708 /* Returns:     u_short* - pointer to transport header checksum to update,  */
5709 /*                         NULL if the transport protocol is not recognised */
5710 /*                         as needing a checksum update.                    */
5711 /* Parameters:  fin(I)    - pointer to packet information                   */
5712 /*              nat(I)    - pointer to NAT structure                        */
5713 /*              nflags(I) - NAT flags set for this packet                   */
5714 /*                                                                          */
5715 /* Return the pointer to the checksum field for each protocol so understood.*/
5716 /* If support for making other changes to a protocol header is required,    */
5717 /* that is not strictly 'address' translation, such as clamping the MSS in  */
5718 /* TCP down to a specific value, then do it from here.                      */
5719 /* ------------------------------------------------------------------------ */
5720 u_short *
ipf_nat_proto(fr_info_t * fin,nat_t * nat,u_int nflags)5721 ipf_nat_proto(fr_info_t *fin, nat_t *nat, u_int nflags)
5722 {
5723 	icmphdr_t *icmp;
5724 	u_short *csump;
5725 	tcphdr_t *tcp;
5726 	udphdr_t *udp;
5727 
5728 	csump = NULL;
5729 	if (fin->fin_out == 0) {
5730 		fin->fin_rev = (nat->nat_dir & NAT_OUTBOUND);
5731 	} else {
5732 		fin->fin_rev = ((nat->nat_dir & NAT_OUTBOUND) == 0);
5733 	}
5734 
5735 	switch (fin->fin_p)
5736 	{
5737 	case IPPROTO_TCP :
5738 		tcp = fin->fin_dp;
5739 
5740 		if ((nflags & IPN_TCP) != 0)
5741 			csump = &tcp->th_sum;
5742 
5743 		/*
5744 		 * Do a MSS CLAMPING on a SYN packet,
5745 		 * only deal IPv4 for now.
5746 		 */
5747 		if ((nat->nat_mssclamp != 0) && (tcp->th_flags & TH_SYN) != 0)
5748 			ipf_nat_mssclamp(tcp, nat->nat_mssclamp, fin, csump);
5749 
5750 		break;
5751 
5752 	case IPPROTO_UDP :
5753 		udp = fin->fin_dp;
5754 
5755 		if ((nflags & IPN_UDP) != 0) {
5756 			if (udp->uh_sum != 0)
5757 				csump = &udp->uh_sum;
5758 		}
5759 		break;
5760 
5761 	case IPPROTO_ICMP :
5762 		icmp = fin->fin_dp;
5763 
5764 		if ((nflags & IPN_ICMPQUERY) != 0) {
5765 			if (icmp->icmp_cksum != 0)
5766 				csump = &icmp->icmp_cksum;
5767 		}
5768 		break;
5769 
5770 #ifdef USE_INET6
5771 	case IPPROTO_ICMPV6 :
5772 	    {
5773 		struct icmp6_hdr *icmp6 = (struct icmp6_hdr *)fin->fin_dp;
5774 
5775 		icmp6 = fin->fin_dp;
5776 
5777 		if ((nflags & IPN_ICMPQUERY) != 0) {
5778 			if (icmp6->icmp6_cksum != 0)
5779 				csump = &icmp6->icmp6_cksum;
5780 		}
5781 		break;
5782 	    }
5783 #endif
5784 	}
5785 	return csump;
5786 }
5787 
5788 
5789 /* ------------------------------------------------------------------------ */
5790 /* Function:    ipf_nat_expire                                              */
5791 /* Returns:     Nil                                                         */
5792 /* Parameters:  softc(I) - pointer to soft context main structure           */
5793 /*                                                                          */
5794 /* Check all of the timeout queues for entries at the top which need to be  */
5795 /* expired.                                                                 */
5796 /* ------------------------------------------------------------------------ */
5797 void
ipf_nat_expire(ipf_main_softc_t * softc)5798 ipf_nat_expire(ipf_main_softc_t *softc)
5799 {
5800 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
5801 	ipftq_t *ifq, *ifqnext;
5802 	ipftqent_t *tqe, *tqn;
5803 	int i;
5804 	SPL_INT(s);
5805 
5806 	SPL_NET(s);
5807 	WRITE_ENTER(&softc->ipf_nat);
5808 	for (ifq = softn->ipf_nat_tcptq, i = 0; ifq != NULL;
5809 	     ifq = ifq->ifq_next) {
5810 		for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); i++) {
5811 			if (tqe->tqe_die > softc->ipf_ticks)
5812 				break;
5813 			tqn = tqe->tqe_next;
5814 			ipf_nat_delete(softc, tqe->tqe_parent, NL_EXPIRE);
5815 		}
5816 	}
5817 
5818 	for (ifq = softn->ipf_nat_utqe; ifq != NULL; ifq = ifq->ifq_next) {
5819 		for (tqn = ifq->ifq_head; ((tqe = tqn) != NULL); i++) {
5820 			if (tqe->tqe_die > softc->ipf_ticks)
5821 				break;
5822 			tqn = tqe->tqe_next;
5823 			ipf_nat_delete(softc, tqe->tqe_parent, NL_EXPIRE);
5824 		}
5825 	}
5826 
5827 	for (ifq = softn->ipf_nat_utqe; ifq != NULL; ifq = ifqnext) {
5828 		ifqnext = ifq->ifq_next;
5829 
5830 		if (((ifq->ifq_flags & IFQF_DELETE) != 0) &&
5831 		    (ifq->ifq_ref == 0)) {
5832 			ipf_freetimeoutqueue(softc, ifq);
5833 		}
5834 	}
5835 
5836 	if (softn->ipf_nat_doflush != 0) {
5837 		ipf_nat_extraflush(softc, softn, 2);
5838 		softn->ipf_nat_doflush = 0;
5839 	}
5840 
5841 	RWLOCK_EXIT(&softc->ipf_nat);
5842 	SPL_X(s);
5843 }
5844 
5845 
5846 /* ------------------------------------------------------------------------ */
5847 /* Function:    ipf_nat_sync                                                */
5848 /* Returns:     Nil                                                         */
5849 /* Parameters:  softc(I) - pointer to soft context main structure           */
5850 /*              ifp(I) - pointer to network interface                       */
5851 /*                                                                          */
5852 /* Walk through all of the currently active NAT sessions, looking for those */
5853 /* which need to have their translated address updated.                     */
5854 /* ------------------------------------------------------------------------ */
5855 void
ipf_nat_sync(ipf_main_softc_t * softc,void * ifp)5856 ipf_nat_sync(ipf_main_softc_t *softc, void *ifp)
5857 {
5858 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
5859 	u_32_t sum1, sum2, sumd;
5860 	i6addr_t in;
5861 	ipnat_t *n;
5862 	nat_t *nat;
5863 	void *ifp2;
5864 	int idx;
5865 	SPL_INT(s);
5866 
5867 	if (softc->ipf_running <= 0)
5868 		return;
5869 
5870 	/*
5871 	 * Change IP addresses for NAT sessions for any protocol except TCP
5872 	 * since it will break the TCP connection anyway.  The only rules
5873 	 * which will get changed are those which are "map ... -> 0/32",
5874 	 * where the rule specifies the address is taken from the interface.
5875 	 */
5876 	SPL_NET(s);
5877 	WRITE_ENTER(&softc->ipf_nat);
5878 
5879 	if (softc->ipf_running <= 0) {
5880 		RWLOCK_EXIT(&softc->ipf_nat);
5881 		return;
5882 	}
5883 
5884 	for (nat = softn->ipf_nat_instances; nat; nat = nat->nat_next) {
5885 		if ((nat->nat_flags & IPN_TCP) != 0)
5886 			continue;
5887 
5888 		n = nat->nat_ptr;
5889 		if (n != NULL) {
5890 			if (n->in_v[1] == 4) {
5891 				if (n->in_redir & NAT_MAP) {
5892 					if ((n->in_nsrcaddr != 0) ||
5893 					    (n->in_nsrcmsk != 0xffffffff))
5894 						continue;
5895 				} else if (n->in_redir & NAT_REDIRECT) {
5896 					if ((n->in_ndstaddr != 0) ||
5897 					    (n->in_ndstmsk != 0xffffffff))
5898 						continue;
5899 				}
5900 			}
5901 #ifdef USE_INET6
5902 			if (n->in_v[1] == 4) {
5903 				if (n->in_redir & NAT_MAP) {
5904 					if (!IP6_ISZERO(&n->in_nsrcaddr) ||
5905 					    !IP6_ISONES(&n->in_nsrcmsk))
5906 						continue;
5907 				} else if (n->in_redir & NAT_REDIRECT) {
5908 					if (!IP6_ISZERO(&n->in_ndstaddr) ||
5909 					    !IP6_ISONES(&n->in_ndstmsk))
5910 						continue;
5911 				}
5912 			}
5913 #endif
5914 		}
5915 
5916 		if (((ifp == NULL) || (ifp == nat->nat_ifps[0]) ||
5917 		     (ifp == nat->nat_ifps[1]))) {
5918 			nat->nat_ifps[0] = GETIFP(nat->nat_ifnames[0],
5919 						  nat->nat_v[0]);
5920 			if ((nat->nat_ifps[0] != NULL) &&
5921 			    (nat->nat_ifps[0] != (void *)-1)) {
5922 				nat->nat_mtu[0] = GETIFMTU_4(nat->nat_ifps[0]);
5923 			}
5924 			if (nat->nat_ifnames[1][0] != '\0') {
5925 				nat->nat_ifps[1] = GETIFP(nat->nat_ifnames[1],
5926 							  nat->nat_v[1]);
5927 			} else {
5928 				nat->nat_ifps[1] = nat->nat_ifps[0];
5929 			}
5930 			if ((nat->nat_ifps[1] != NULL) &&
5931 			    (nat->nat_ifps[1] != (void *)-1)) {
5932 				nat->nat_mtu[1] = GETIFMTU_4(nat->nat_ifps[1]);
5933 			}
5934 			ifp2 = nat->nat_ifps[0];
5935 			if (ifp2 == NULL)
5936 				continue;
5937 
5938 			/*
5939 			 * Change the map-to address to be the same as the
5940 			 * new one.
5941 			 */
5942 			sum1 = NATFSUM(nat, nat->nat_v[1], nat_nsrc6);
5943 			if (ipf_ifpaddr(softc, nat->nat_v[0], FRI_NORMAL, ifp2,
5944 				       &in, NULL) != -1) {
5945 				if (nat->nat_v[0] == 4)
5946 					nat->nat_nsrcip = in.in4;
5947 			}
5948 			sum2 = NATFSUM(nat, nat->nat_v[1], nat_nsrc6);
5949 
5950 			if (sum1 == sum2)
5951 				continue;
5952 			/*
5953 			 * Readjust the checksum adjustment to take into
5954 			 * account the new IP#.
5955 			 */
5956 			CALC_SUMD(sum1, sum2, sumd);
5957 			/* XXX - dont change for TCP when solaris does
5958 			 * hardware checksumming.
5959 			 */
5960 			sumd += nat->nat_sumd[0];
5961 			nat->nat_sumd[0] = (sumd & 0xffff) + (sumd >> 16);
5962 			nat->nat_sumd[1] = nat->nat_sumd[0];
5963 		}
5964 	}
5965 
5966 	for (n = softn->ipf_nat_list; (n != NULL); n = n->in_next) {
5967 		char *base = n->in_names;
5968 
5969 		if ((ifp == NULL) || (n->in_ifps[0] == ifp))
5970 			n->in_ifps[0] = ipf_resolvenic(softc,
5971 						       base + n->in_ifnames[0],
5972 						       n->in_v[0]);
5973 		if ((ifp == NULL) || (n->in_ifps[1] == ifp))
5974 			n->in_ifps[1] = ipf_resolvenic(softc,
5975 						       base + n->in_ifnames[1],
5976 						       n->in_v[1]);
5977 
5978 		if (n->in_redir & NAT_REDIRECT)
5979 			idx = 1;
5980 		else
5981 			idx = 0;
5982 
5983 		if (((ifp == NULL) || (n->in_ifps[idx] == ifp)) &&
5984 		    (n->in_ifps[idx] != NULL &&
5985 		     n->in_ifps[idx] != (void *)-1)) {
5986 
5987 			ipf_nat_nextaddrinit(softc, n->in_names, &n->in_osrc,
5988 					     0, n->in_ifps[idx]);
5989 			ipf_nat_nextaddrinit(softc, n->in_names, &n->in_odst,
5990 					     0, n->in_ifps[idx]);
5991 			ipf_nat_nextaddrinit(softc, n->in_names, &n->in_nsrc,
5992 					     0, n->in_ifps[idx]);
5993 			ipf_nat_nextaddrinit(softc, n->in_names, &n->in_ndst,
5994 					     0, n->in_ifps[idx]);
5995 		}
5996 	}
5997 	RWLOCK_EXIT(&softc->ipf_nat);
5998 	SPL_X(s);
5999 }
6000 
6001 
6002 /* ------------------------------------------------------------------------ */
6003 /* Function:    ipf_nat_icmpquerytype                                       */
6004 /* Returns:     int - 1 == success, 0 == failure                            */
6005 /* Parameters:  icmptype(I) - ICMP type number                              */
6006 /*                                                                          */
6007 /* Tests to see if the ICMP type number passed is a query/response type or  */
6008 /* not.                                                                     */
6009 /* ------------------------------------------------------------------------ */
6010 static int
ipf_nat_icmpquerytype(int icmptype)6011 ipf_nat_icmpquerytype(int icmptype)
6012 {
6013 
6014 	/*
6015 	 * For the ICMP query NAT code, it is essential that both the query
6016 	 * and the reply match on the NAT rule. Because the NAT structure
6017 	 * does not keep track of the icmptype, and a single NAT structure
6018 	 * is used for all icmp types with the same src, dest and id, we
6019 	 * simply define the replies as queries as well. The funny thing is,
6020 	 * although it seems silly to call a reply a query, this is exactly
6021 	 * as it is defined in the IPv4 specification
6022 	 */
6023 	switch (icmptype)
6024 	{
6025 	case ICMP_ECHOREPLY:
6026 	case ICMP_ECHO:
6027 	/* route advertisement/sollicitation is currently unsupported: */
6028 	/* it would require rewriting the ICMP data section            */
6029 	case ICMP_TSTAMP:
6030 	case ICMP_TSTAMPREPLY:
6031 	case ICMP_IREQ:
6032 	case ICMP_IREQREPLY:
6033 	case ICMP_MASKREQ:
6034 	case ICMP_MASKREPLY:
6035 		return 1;
6036 	default:
6037 		return 0;
6038 	}
6039 }
6040 
6041 
6042 /* ------------------------------------------------------------------------ */
6043 /* Function:    nat_log                                                     */
6044 /* Returns:     Nil                                                         */
6045 /* Parameters:  softc(I) - pointer to soft context main structure           */
6046 /*              softn(I) - pointer to NAT context structure                 */
6047 /*              nat(I)    - pointer to NAT structure                        */
6048 /*              action(I) - action related to NAT structure being performed */
6049 /*                                                                          */
6050 /* Creates a NAT log entry.                                                 */
6051 /* ------------------------------------------------------------------------ */
6052 void
ipf_nat_log(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,struct nat * nat,u_int action)6053 ipf_nat_log(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, struct nat *nat,
6054     u_int action)
6055 {
6056 #ifdef	IPFILTER_LOG
6057 # ifndef LARGE_NAT
6058 	struct ipnat *np;
6059 	int rulen;
6060 # endif
6061 	struct natlog natl;
6062 	void *items[1];
6063 	size_t sizes[1];
6064 	int types[1];
6065 
6066 	bcopy((char *)&nat->nat_osrc6, (char *)&natl.nl_osrcip,
6067 	      sizeof(natl.nl_osrcip));
6068 	bcopy((char *)&nat->nat_nsrc6, (char *)&natl.nl_nsrcip,
6069 	      sizeof(natl.nl_nsrcip));
6070 	bcopy((char *)&nat->nat_odst6, (char *)&natl.nl_odstip,
6071 	      sizeof(natl.nl_odstip));
6072 	bcopy((char *)&nat->nat_ndst6, (char *)&natl.nl_ndstip,
6073 	      sizeof(natl.nl_ndstip));
6074 
6075 	natl.nl_bytes[0] = nat->nat_bytes[0];
6076 	natl.nl_bytes[1] = nat->nat_bytes[1];
6077 	natl.nl_pkts[0] = nat->nat_pkts[0];
6078 	natl.nl_pkts[1] = nat->nat_pkts[1];
6079 	natl.nl_odstport = nat->nat_odport;
6080 	natl.nl_osrcport = nat->nat_osport;
6081 	natl.nl_nsrcport = nat->nat_nsport;
6082 	natl.nl_ndstport = nat->nat_ndport;
6083 	natl.nl_p[0] = nat->nat_pr[0];
6084 	natl.nl_p[1] = nat->nat_pr[1];
6085 	natl.nl_v[0] = nat->nat_v[0];
6086 	natl.nl_v[1] = nat->nat_v[1];
6087 	natl.nl_type = nat->nat_redir;
6088 	natl.nl_action = action;
6089 	natl.nl_rule = -1;
6090 
6091 	bcopy(nat->nat_ifnames[0], natl.nl_ifnames[0],
6092 	      sizeof(nat->nat_ifnames[0]));
6093 	bcopy(nat->nat_ifnames[1], natl.nl_ifnames[1],
6094 	      sizeof(nat->nat_ifnames[1]));
6095 
6096 # ifndef LARGE_NAT
6097 	if (nat->nat_ptr != NULL) {
6098 		for (rulen = 0, np = softn->ipf_nat_list; np != NULL;
6099 		     np = np->in_next, rulen++)
6100 			if (np == nat->nat_ptr) {
6101 				natl.nl_rule = rulen;
6102 				break;
6103 			}
6104 	}
6105 # endif
6106 	items[0] = &natl;
6107 	sizes[0] = sizeof(natl);
6108 	types[0] = 0;
6109 
6110 	(void) ipf_log_items(softc, IPL_LOGNAT, NULL, items, sizes, types, 1);
6111 #endif
6112 }
6113 
6114 
6115 #if defined(__OpenBSD__)
6116 /* ------------------------------------------------------------------------ */
6117 /* Function:    ipf_nat_ifdetach                                            */
6118 /* Returns:     Nil                                                         */
6119 /* Parameters:  ifp(I) - pointer to network interface                       */
6120 /*                                                                          */
6121 /* Compatibility interface for OpenBSD to trigger the correct updating of   */
6122 /* interface references within IPFilter.                                    */
6123 /* ------------------------------------------------------------------------ */
6124 void
ipf_nat_ifdetach(ifp)6125 ipf_nat_ifdetach(ifp)
6126 	void *ifp;
6127 {
6128 	ipf_main_softc_t *softc;
6129 
6130 	softc = ipf_get_softc(0);
6131 
6132 	ipf_sync(ifp);
6133 	return;
6134 }
6135 #endif
6136 
6137 
6138 /* ------------------------------------------------------------------------ */
6139 /* Function:    ipf_nat_rule_deref                                          */
6140 /* Returns:     Nil                                                         */
6141 /* Parameters:  softc(I) - pointer to soft context main structure           */
6142 /*              inp(I)   - pointer to pointer to NAT rule                   */
6143 /* Write Locks: ipf_nat                                                     */
6144 /*                                                                          */
6145 /* Dropping the refernce count for a rule means that whatever held the      */
6146 /* pointer to this rule (*inp) is no longer interested in it and when the   */
6147 /* reference count drops to zero, any resources allocated for the rule can  */
6148 /* be released and the rule itself free'd.                                  */
6149 /* ------------------------------------------------------------------------ */
6150 void
ipf_nat_rule_deref(ipf_main_softc_t * softc,ipnat_t ** inp)6151 ipf_nat_rule_deref(ipf_main_softc_t *softc, ipnat_t **inp)
6152 {
6153 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
6154 	ipnat_t *n;
6155 
6156 	n = *inp;
6157 	*inp = NULL;
6158 	n->in_use--;
6159 	if (n->in_use > 0)
6160 		return;
6161 
6162 	if (n->in_apr != NULL)
6163 		ipf_proxy_deref(n->in_apr);
6164 
6165 	ipf_nat_rule_fini(softc, n);
6166 
6167 	if (n->in_redir & NAT_REDIRECT) {
6168 		if ((n->in_flags & IPN_PROXYRULE) == 0) {
6169 			ATOMIC_DEC32(softn->ipf_nat_stats.ns_rules_rdr);
6170 		}
6171 	}
6172 	if (n->in_redir & (NAT_MAP|NAT_MAPBLK)) {
6173 		if ((n->in_flags & IPN_PROXYRULE) == 0) {
6174 			ATOMIC_DEC32(softn->ipf_nat_stats.ns_rules_map);
6175 		}
6176 	}
6177 
6178 	if (n->in_tqehead[0] != NULL) {
6179 		if (ipf_deletetimeoutqueue(n->in_tqehead[0]) == 0) {
6180 			ipf_freetimeoutqueue(softc, n->in_tqehead[0]);
6181 		}
6182 	}
6183 
6184 	if (n->in_tqehead[1] != NULL) {
6185 		if (ipf_deletetimeoutqueue(n->in_tqehead[1]) == 0) {
6186 			ipf_freetimeoutqueue(softc, n->in_tqehead[1]);
6187 		}
6188 	}
6189 
6190 	if ((n->in_flags & IPN_PROXYRULE) == 0) {
6191 		ATOMIC_DEC32(softn->ipf_nat_stats.ns_rules);
6192 	}
6193 
6194 	MUTEX_DESTROY(&n->in_lock);
6195 
6196 	KFREES(n, n->in_size);
6197 
6198 #if SOLARIS && !defined(INSTANCES)
6199 	if (softn->ipf_nat_stats.ns_rules == 0)
6200 		pfil_delayed_copy = 1;
6201 #endif
6202 }
6203 
6204 
6205 /* ------------------------------------------------------------------------ */
6206 /* Function:    ipf_nat_deref                                               */
6207 /* Returns:     Nil                                                         */
6208 /* Parameters:  softc(I) - pointer to soft context main structure           */
6209 /*              natp(I)  - pointer to pointer to NAT table entry            */
6210 /*                                                                          */
6211 /* Decrement the reference counter for this NAT table entry and free it if  */
6212 /* there are no more things using it.                                       */
6213 /*                                                                          */
6214 /* IF nat_ref == 1 when this function is called, then we have an orphan nat */
6215 /* structure *because* it only gets called on paths _after_ nat_ref has been*/
6216 /* incremented.  If nat_ref == 1 then we shouldn't decrement it here        */
6217 /* because nat_delete() will do that and send nat_ref to -1.                */
6218 /*                                                                          */
6219 /* Holding the lock on nat_lock is required to serialise nat_delete() being */
6220 /* called from a NAT flush ioctl with a deref happening because of a packet.*/
6221 /* ------------------------------------------------------------------------ */
6222 void
ipf_nat_deref(ipf_main_softc_t * softc,nat_t ** natp)6223 ipf_nat_deref(ipf_main_softc_t *softc, nat_t **natp)
6224 {
6225 	nat_t *nat;
6226 
6227 	nat = *natp;
6228 	*natp = NULL;
6229 
6230 	MUTEX_ENTER(&nat->nat_lock);
6231 	if (nat->nat_ref > 1) {
6232 		nat->nat_ref--;
6233 		ASSERT(nat->nat_ref >= 0);
6234 		MUTEX_EXIT(&nat->nat_lock);
6235 		return;
6236 	}
6237 	MUTEX_EXIT(&nat->nat_lock);
6238 
6239 	WRITE_ENTER(&softc->ipf_nat);
6240 	ipf_nat_delete(softc, nat, NL_EXPIRE);
6241 	RWLOCK_EXIT(&softc->ipf_nat);
6242 }
6243 
6244 
6245 /* ------------------------------------------------------------------------ */
6246 /* Function:    ipf_nat_clone                                               */
6247 /* Returns:     ipstate_t* - NULL == cloning failed,                        */
6248 /*                           else pointer to new state structure            */
6249 /* Parameters:  fin(I) - pointer to packet information                      */
6250 /*              is(I)  - pointer to master state structure                  */
6251 /* Write Lock:  ipf_nat                                                     */
6252 /*                                                                          */
6253 /* Create a "duplcate" state table entry from the master.                   */
6254 /* ------------------------------------------------------------------------ */
6255 nat_t *
ipf_nat_clone(fr_info_t * fin,nat_t * nat)6256 ipf_nat_clone(fr_info_t *fin, nat_t *nat)
6257 {
6258 	ipf_main_softc_t *softc = fin->fin_main_soft;
6259 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
6260 	frentry_t *fr;
6261 	nat_t *clone;
6262 	ipnat_t *np;
6263 
6264 	KMALLOC(clone, nat_t *);
6265 	if (clone == NULL) {
6266 		NBUMPSIDED(fin->fin_out, ns_clone_nomem);
6267 		return NULL;
6268 	}
6269 	bcopy((char *)nat, (char *)clone, sizeof(*clone));
6270 
6271 	MUTEX_NUKE(&clone->nat_lock);
6272 
6273 	clone->nat_rev = fin->fin_rev;
6274 	clone->nat_aps = NULL;
6275 	/*
6276 	 * Initialize all these so that ipf_nat_delete() doesn't cause a crash.
6277 	 */
6278 	clone->nat_tqe.tqe_pnext = NULL;
6279 	clone->nat_tqe.tqe_next = NULL;
6280 	clone->nat_tqe.tqe_ifq = NULL;
6281 	clone->nat_tqe.tqe_parent = clone;
6282 
6283 	clone->nat_flags &= ~SI_CLONE;
6284 	clone->nat_flags |= SI_CLONED;
6285 
6286 	if (clone->nat_hm)
6287 		clone->nat_hm->hm_ref++;
6288 
6289 	if (ipf_nat_insert(softc, softn, clone) == -1) {
6290 		KFREE(clone);
6291 		NBUMPSIDED(fin->fin_out, ns_insert_fail);
6292 		return NULL;
6293 	}
6294 
6295 	np = clone->nat_ptr;
6296 	if (np != NULL) {
6297 		if (softn->ipf_nat_logging)
6298 			ipf_nat_log(softc, softn, clone, NL_CLONE);
6299 		np->in_use++;
6300 	}
6301 	fr = clone->nat_fr;
6302 	if (fr != NULL) {
6303 		MUTEX_ENTER(&fr->fr_lock);
6304 		fr->fr_ref++;
6305 		MUTEX_EXIT(&fr->fr_lock);
6306 	}
6307 
6308 
6309 	/*
6310 	 * Because the clone is created outside the normal loop of things and
6311 	 * TCP has special needs in terms of state, initialise the timeout
6312 	 * state of the new NAT from here.
6313 	 */
6314 	if (clone->nat_pr[0] == IPPROTO_TCP) {
6315 		(void) ipf_tcp_age(&clone->nat_tqe, fin, softn->ipf_nat_tcptq,
6316 				   clone->nat_flags, 2);
6317 	}
6318 	clone->nat_sync = ipf_sync_new(softc, SMC_NAT, fin, clone);
6319 	if (softn->ipf_nat_logging)
6320 		ipf_nat_log(softc, softn, clone, NL_CLONE);
6321 	return clone;
6322 }
6323 
6324 
6325 /* ------------------------------------------------------------------------ */
6326 /* Function:   ipf_nat_wildok                                               */
6327 /* Returns:    int - 1 == packet's ports match wildcards                    */
6328 /*                   0 == packet's ports don't match wildcards              */
6329 /* Parameters: nat(I)   - NAT entry                                         */
6330 /*             sport(I) - source port                                       */
6331 /*             dport(I) - destination port                                  */
6332 /*             flags(I) - wildcard flags                                    */
6333 /*             dir(I)   - packet direction                                  */
6334 /*                                                                          */
6335 /* Use NAT entry and packet direction to determine which combination of     */
6336 /* wildcard flags should be used.                                           */
6337 /* ------------------------------------------------------------------------ */
6338 int
ipf_nat_wildok(nat_t * nat,int sport,int dport,int flags,int dir)6339 ipf_nat_wildok(nat_t *nat, int sport, int dport, int flags, int dir)
6340 {
6341 	/*
6342 	 * When called by       dir is set to
6343 	 * nat_inlookup         NAT_INBOUND (0)
6344 	 * nat_outlookup        NAT_OUTBOUND (1)
6345 	 *
6346 	 * We simply combine the packet's direction in dir with the original
6347 	 * "intended" direction of that NAT entry in nat->nat_dir to decide
6348 	 * which combination of wildcard flags to allow.
6349 	 */
6350 	switch ((dir << 1) | (nat->nat_dir & (NAT_INBOUND|NAT_OUTBOUND)))
6351 	{
6352 	case 3: /* outbound packet / outbound entry */
6353 		if (((nat->nat_osport == sport) ||
6354 		    (flags & SI_W_SPORT)) &&
6355 		    ((nat->nat_odport == dport) ||
6356 		    (flags & SI_W_DPORT)))
6357 			return 1;
6358 		break;
6359 	case 2: /* outbound packet / inbound entry */
6360 		if (((nat->nat_osport == dport) ||
6361 		    (flags & SI_W_SPORT)) &&
6362 		    ((nat->nat_odport == sport) ||
6363 		    (flags & SI_W_DPORT)))
6364 			return 1;
6365 		break;
6366 	case 1: /* inbound packet / outbound entry */
6367 		if (((nat->nat_osport == dport) ||
6368 		    (flags & SI_W_SPORT)) &&
6369 		    ((nat->nat_odport == sport) ||
6370 		    (flags & SI_W_DPORT)))
6371 			return 1;
6372 		break;
6373 	case 0: /* inbound packet / inbound entry */
6374 		if (((nat->nat_osport == sport) ||
6375 		    (flags & SI_W_SPORT)) &&
6376 		    ((nat->nat_odport == dport) ||
6377 		    (flags & SI_W_DPORT)))
6378 			return 1;
6379 		break;
6380 	default:
6381 		break;
6382 	}
6383 
6384 	return(0);
6385 }
6386 
6387 
6388 /* ------------------------------------------------------------------------ */
6389 /* Function:    nat_mssclamp                                                */
6390 /* Returns:     Nil                                                         */
6391 /* Parameters:  tcp(I)    - pointer to TCP header                           */
6392 /*              maxmss(I) - value to clamp the TCP MSS to                   */
6393 /*              fin(I)    - pointer to packet information                   */
6394 /*              csump(I)  - pointer to TCP checksum                         */
6395 /*                                                                          */
6396 /* Check for MSS option and clamp it if necessary.  If found and changed,   */
6397 /* then the TCP header checksum will be updated to reflect the change in    */
6398 /* the MSS.                                                                 */
6399 /* ------------------------------------------------------------------------ */
6400 static void
ipf_nat_mssclamp(tcphdr_t * tcp,u_32_t maxmss,fr_info_t * fin,u_short * csump)6401 ipf_nat_mssclamp(tcphdr_t *tcp, u_32_t maxmss, fr_info_t *fin, u_short *csump)
6402 {
6403 	u_char *cp, *ep, opt;
6404 	int hlen, advance;
6405 	u_32_t mss, sumd;
6406 
6407 	hlen = TCP_OFF(tcp) << 2;
6408 	if (hlen > sizeof(*tcp)) {
6409 		cp = (u_char *)tcp + sizeof(*tcp);
6410 		ep = (u_char *)tcp + hlen;
6411 
6412 		while (cp < ep) {
6413 			opt = cp[0];
6414 			if (opt == TCPOPT_EOL)
6415 				break;
6416 			else if (opt == TCPOPT_NOP) {
6417 				cp++;
6418 				continue;
6419 			}
6420 
6421 			if (cp + 1 >= ep)
6422 				break;
6423 			advance = cp[1];
6424 			if ((cp + advance > ep) || (advance <= 0))
6425 				break;
6426 			switch (opt)
6427 			{
6428 			case TCPOPT_MAXSEG:
6429 				if (advance != 4)
6430 					break;
6431 				mss = cp[2] * 256 + cp[3];
6432 				if (mss > maxmss) {
6433 					cp[2] = maxmss / 256;
6434 					cp[3] = maxmss & 0xff;
6435 					CALC_SUMD(mss, maxmss, sumd);
6436 					ipf_fix_outcksum(0, csump, sumd, 0);
6437 				}
6438 				break;
6439 			default:
6440 				/* ignore unknown options */
6441 				break;
6442 			}
6443 
6444 			cp += advance;
6445 		}
6446 	}
6447 }
6448 
6449 
6450 /* ------------------------------------------------------------------------ */
6451 /* Function:    ipf_nat_setqueue                                            */
6452 /* Returns:     Nil                                                         */
6453 /* Parameters:  softc(I) - pointer to soft context main structure           */
6454 /*              softn(I) - pointer to NAT context structure                 */
6455 /*              nat(I)- pointer to NAT structure                            */
6456 /* Locks:       ipf_nat (read or write)                                     */
6457 /*                                                                          */
6458 /* Put the NAT entry on its default queue entry, using rev as a helped in   */
6459 /* determining which queue it should be placed on.                          */
6460 /* ------------------------------------------------------------------------ */
6461 void
ipf_nat_setqueue(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,nat_t * nat)6462 ipf_nat_setqueue(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, nat_t *nat)
6463 {
6464 	ipftq_t *oifq, *nifq;
6465 	int rev = nat->nat_rev;
6466 
6467 	if (nat->nat_ptr != NULL)
6468 		nifq = nat->nat_ptr->in_tqehead[rev];
6469 	else
6470 		nifq = NULL;
6471 
6472 	if (nifq == NULL) {
6473 		switch (nat->nat_pr[0])
6474 		{
6475 		case IPPROTO_UDP :
6476 			nifq = &softn->ipf_nat_udptq;
6477 			break;
6478 		case IPPROTO_ICMP :
6479 			nifq = &softn->ipf_nat_icmptq;
6480 			break;
6481 		case IPPROTO_TCP :
6482 			nifq = softn->ipf_nat_tcptq +
6483 			       nat->nat_tqe.tqe_state[rev];
6484 			break;
6485 		default :
6486 			nifq = &softn->ipf_nat_iptq;
6487 			break;
6488 		}
6489 	}
6490 
6491 	oifq = nat->nat_tqe.tqe_ifq;
6492 	/*
6493 	 * If it's currently on a timeout queue, move it from one queue to
6494 	 * another, else put it on the end of the newly determined queue.
6495 	 */
6496 	if (oifq != NULL)
6497 		ipf_movequeue(softc->ipf_ticks, &nat->nat_tqe, oifq, nifq);
6498 	else
6499 		ipf_queueappend(softc->ipf_ticks, &nat->nat_tqe, nifq, nat);
6500 	return;
6501 }
6502 
6503 
6504 /* ------------------------------------------------------------------------ */
6505 /* Function:    nat_getnext                                                 */
6506 /* Returns:     int - 0 == ok, else error                                   */
6507 /* Parameters:  softc(I) - pointer to soft context main structure           */
6508 /*              t(I)   - pointer to ipftoken structure                      */
6509 /*              itp(I) - pointer to ipfgeniter_t structure                  */
6510 /*                                                                          */
6511 /* Fetch the next nat/ipnat structure pointer from the linked list and      */
6512 /* copy it out to the storage space pointed to by itp_data.  The next item  */
6513 /* in the list to look at is put back in the ipftoken struture.             */
6514 /* ------------------------------------------------------------------------ */
6515 static int
ipf_nat_getnext(ipf_main_softc_t * softc,ipftoken_t * t,ipfgeniter_t * itp,ipfobj_t * objp)6516 ipf_nat_getnext(ipf_main_softc_t *softc, ipftoken_t *t, ipfgeniter_t *itp,
6517     ipfobj_t *objp)
6518 {
6519 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
6520 	hostmap_t *hm, *nexthm = NULL, zerohm;
6521 	ipnat_t *ipn, *nextipnat = NULL, zeroipn;
6522 	nat_t *nat, *nextnat = NULL, zeronat;
6523 	int error = 0;
6524 	void *nnext;
6525 
6526 	if (itp->igi_nitems != 1) {
6527 		IPFERROR(60075);
6528 		return ENOSPC;
6529 	}
6530 
6531 	READ_ENTER(&softc->ipf_nat);
6532 
6533 	switch (itp->igi_type)
6534 	{
6535 	case IPFGENITER_HOSTMAP :
6536 		hm = t->ipt_data;
6537 		if (hm == NULL) {
6538 			nexthm = softn->ipf_hm_maplist;
6539 		} else {
6540 			nexthm = hm->hm_next;
6541 		}
6542 		if (nexthm != NULL) {
6543 			ATOMIC_INC32(nexthm->hm_ref);
6544 			t->ipt_data = nexthm;
6545 		} else {
6546 			bzero(&zerohm, sizeof(zerohm));
6547 			nexthm = &zerohm;
6548 			t->ipt_data = NULL;
6549 		}
6550 		nnext = nexthm->hm_next;
6551 		break;
6552 
6553 	case IPFGENITER_IPNAT :
6554 		ipn = t->ipt_data;
6555 		if (ipn == NULL) {
6556 			nextipnat = softn->ipf_nat_list;
6557 		} else {
6558 			nextipnat = ipn->in_next;
6559 		}
6560 		if (nextipnat != NULL) {
6561 			ATOMIC_INC32(nextipnat->in_use);
6562 			t->ipt_data = nextipnat;
6563 		} else {
6564 			bzero(&zeroipn, sizeof(zeroipn));
6565 			nextipnat = &zeroipn;
6566 			t->ipt_data = NULL;
6567 		}
6568 		nnext = nextipnat->in_next;
6569 		break;
6570 
6571 	case IPFGENITER_NAT :
6572 		nat = t->ipt_data;
6573 		if (nat == NULL) {
6574 			nextnat = softn->ipf_nat_instances;
6575 		} else {
6576 			nextnat = nat->nat_next;
6577 		}
6578 		if (nextnat != NULL) {
6579 			MUTEX_ENTER(&nextnat->nat_lock);
6580 			nextnat->nat_ref++;
6581 			MUTEX_EXIT(&nextnat->nat_lock);
6582 			t->ipt_data = nextnat;
6583 		} else {
6584 			bzero(&zeronat, sizeof(zeronat));
6585 			nextnat = &zeronat;
6586 			t->ipt_data = NULL;
6587 		}
6588 		nnext = nextnat->nat_next;
6589 		break;
6590 
6591 	default :
6592 		RWLOCK_EXIT(&softc->ipf_nat);
6593 		IPFERROR(60055);
6594 		return EINVAL;
6595 	}
6596 
6597 	RWLOCK_EXIT(&softc->ipf_nat);
6598 
6599 	objp->ipfo_ptr = itp->igi_data;
6600 
6601 	switch (itp->igi_type)
6602 	{
6603 	case IPFGENITER_HOSTMAP :
6604 		error = COPYOUT(nexthm, objp->ipfo_ptr, sizeof(*nexthm));
6605 		if (error != 0) {
6606 			IPFERROR(60049);
6607 			error = EFAULT;
6608 		}
6609 		if (hm != NULL) {
6610 			WRITE_ENTER(&softc->ipf_nat);
6611 			ipf_nat_hostmapdel(softc, &hm);
6612 			RWLOCK_EXIT(&softc->ipf_nat);
6613 		}
6614 		break;
6615 
6616 	case IPFGENITER_IPNAT :
6617 		objp->ipfo_size = nextipnat->in_size;
6618 		objp->ipfo_type = IPFOBJ_IPNAT;
6619 		error = ipf_outobjk(softc, objp, nextipnat);
6620 		if (ipn != NULL) {
6621 			WRITE_ENTER(&softc->ipf_nat);
6622 			ipf_nat_rule_deref(softc, &ipn);
6623 			RWLOCK_EXIT(&softc->ipf_nat);
6624 		}
6625 		break;
6626 
6627 	case IPFGENITER_NAT :
6628 		objp->ipfo_size = sizeof(nat_t);
6629 		objp->ipfo_type = IPFOBJ_NAT;
6630 		error = ipf_outobjk(softc, objp, nextnat);
6631 		if (nat != NULL)
6632 			ipf_nat_deref(softc, &nat);
6633 
6634 		break;
6635 	}
6636 
6637 	if (nnext == NULL)
6638 		ipf_token_mark_complete(t);
6639 
6640 	return error;
6641 }
6642 
6643 
6644 /* ------------------------------------------------------------------------ */
6645 /* Function:    nat_extraflush                                              */
6646 /* Returns:     int - 0 == success, -1 == failure                           */
6647 /* Parameters:  softc(I) - pointer to soft context main structure           */
6648 /*              softn(I) - pointer to NAT context structure                 */
6649 /*              which(I) - how to flush the active NAT table                */
6650 /* Write Locks: ipf_nat                                                     */
6651 /*                                                                          */
6652 /* Flush nat tables.  Three actions currently defined:                      */
6653 /* which == 0 : flush all nat table entries                                 */
6654 /* which == 1 : flush TCP connections which have started to close but are   */
6655 /*	      stuck for some reason.                                        */
6656 /* which == 2 : flush TCP connections which have been idle for a long time, */
6657 /*	      starting at > 4 days idle and working back in successive half-*/
6658 /*	      days to at most 12 hours old.  If this fails to free enough   */
6659 /*            slots then work backwards in half hour slots to 30 minutes.   */
6660 /*            If that too fails, then work backwards in 30 second intervals */
6661 /*            for the last 30 minutes to at worst 30 seconds idle.          */
6662 /* ------------------------------------------------------------------------ */
6663 static int
ipf_nat_extraflush(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,int which)6664 ipf_nat_extraflush(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, int which)
6665 {
6666 	nat_t *nat, **natp;
6667 	ipftqent_t *tqn;
6668 	ipftq_t *ifq;
6669 	int removed;
6670 	SPL_INT(s);
6671 
6672 	removed = 0;
6673 
6674 	SPL_NET(s);
6675 	switch (which)
6676 	{
6677 	case 0 :
6678 		softn->ipf_nat_stats.ns_flush_all++;
6679 		/*
6680 		 * Style 0 flush removes everything...
6681 		 */
6682 		for (natp = &softn->ipf_nat_instances;
6683 		     ((nat = *natp) != NULL); ) {
6684 			ipf_nat_delete(softc, nat, NL_FLUSH);
6685 			removed++;
6686 		}
6687 		break;
6688 
6689 	case 1 :
6690 		softn->ipf_nat_stats.ns_flush_closing++;
6691 		/*
6692 		 * Since we're only interested in things that are closing,
6693 		 * we can start with the appropriate timeout queue.
6694 		 */
6695 		for (ifq = softn->ipf_nat_tcptq + IPF_TCPS_CLOSE_WAIT;
6696 		     ifq != NULL; ifq = ifq->ifq_next) {
6697 
6698 			for (tqn = ifq->ifq_head; tqn != NULL; ) {
6699 				nat = tqn->tqe_parent;
6700 				tqn = tqn->tqe_next;
6701 				if (nat->nat_pr[0] != IPPROTO_TCP ||
6702 				    nat->nat_pr[1] != IPPROTO_TCP)
6703 					break;
6704 				ipf_nat_delete(softc, nat, NL_EXPIRE);
6705 				removed++;
6706 			}
6707 		}
6708 
6709 		/*
6710 		 * Also need to look through the user defined queues.
6711 		 */
6712 		for (ifq = softn->ipf_nat_utqe; ifq != NULL;
6713 		     ifq = ifq->ifq_next) {
6714 			for (tqn = ifq->ifq_head; tqn != NULL; ) {
6715 				nat = tqn->tqe_parent;
6716 				tqn = tqn->tqe_next;
6717 				if (nat->nat_pr[0] != IPPROTO_TCP ||
6718 				    nat->nat_pr[1] != IPPROTO_TCP)
6719 					continue;
6720 
6721 				if ((nat->nat_tcpstate[0] >
6722 				     IPF_TCPS_ESTABLISHED) &&
6723 				    (nat->nat_tcpstate[1] >
6724 				     IPF_TCPS_ESTABLISHED)) {
6725 					ipf_nat_delete(softc, nat, NL_EXPIRE);
6726 					removed++;
6727 				}
6728 			}
6729 		}
6730 		break;
6731 
6732 		/*
6733 		 * Args 5-11 correspond to flushing those particular states
6734 		 * for TCP connections.
6735 		 */
6736 	case IPF_TCPS_CLOSE_WAIT :
6737 	case IPF_TCPS_FIN_WAIT_1 :
6738 	case IPF_TCPS_CLOSING :
6739 	case IPF_TCPS_LAST_ACK :
6740 	case IPF_TCPS_FIN_WAIT_2 :
6741 	case IPF_TCPS_TIME_WAIT :
6742 	case IPF_TCPS_CLOSED :
6743 		softn->ipf_nat_stats.ns_flush_state++;
6744 		tqn = softn->ipf_nat_tcptq[which].ifq_head;
6745 		while (tqn != NULL) {
6746 			nat = tqn->tqe_parent;
6747 			tqn = tqn->tqe_next;
6748 			ipf_nat_delete(softc, nat, NL_FLUSH);
6749 			removed++;
6750 		}
6751 		break;
6752 
6753 	default :
6754 		if (which < 30)
6755 			break;
6756 
6757 		softn->ipf_nat_stats.ns_flush_timeout++;
6758 		/*
6759 		 * Take a large arbitrary number to mean the number of seconds
6760 		 * for which which consider to be the maximum value we'll allow
6761 		 * the expiration to be.
6762 		 */
6763 		which = IPF_TTLVAL(which);
6764 		for (natp = &softn->ipf_nat_instances;
6765 		     ((nat = *natp) != NULL); ) {
6766 			if (softc->ipf_ticks - nat->nat_touched > which) {
6767 				ipf_nat_delete(softc, nat, NL_FLUSH);
6768 				removed++;
6769 			} else
6770 				natp = &nat->nat_next;
6771 		}
6772 		break;
6773 	}
6774 
6775 	if (which != 2) {
6776 		SPL_X(s);
6777 		return removed;
6778 	}
6779 
6780 	softn->ipf_nat_stats.ns_flush_queue++;
6781 
6782 	/*
6783 	 * Asked to remove inactive entries because the table is full, try
6784 	 * again, 3 times, if first attempt failed with a different criteria
6785 	 * each time.  The order tried in must be in decreasing age.
6786 	 * Another alternative is to implement random drop and drop N entries
6787 	 * at random until N have been freed up.
6788 	 */
6789 	if (softc->ipf_ticks - softn->ipf_nat_last_force_flush >
6790 	    IPF_TTLVAL(5)) {
6791 		softn->ipf_nat_last_force_flush = softc->ipf_ticks;
6792 
6793 		removed = ipf_queueflush(softc, ipf_nat_flush_entry,
6794 					 softn->ipf_nat_tcptq,
6795 					 softn->ipf_nat_utqe,
6796 					 &softn->ipf_nat_stats.ns_active,
6797 					 softn->ipf_nat_table_sz,
6798 					 softn->ipf_nat_table_wm_low);
6799 	}
6800 
6801 	SPL_X(s);
6802 	return removed;
6803 }
6804 
6805 
6806 /* ------------------------------------------------------------------------ */
6807 /* Function:    ipf_nat_flush_entry                                         */
6808 /* Returns:     0 - always succeeds                                         */
6809 /* Parameters:  softc(I) - pointer to soft context main structure           */
6810 /*              entry(I) - pointer to NAT entry                             */
6811 /* Write Locks: ipf_nat                                                     */
6812 /*                                                                          */
6813 /* This function is a stepping stone between ipf_queueflush() and           */
6814 /* nat_dlete().  It is used so we can provide a uniform interface via the   */
6815 /* ipf_queueflush() function.  Since the nat_delete() function returns void */
6816 /* we translate that to mean it always succeeds in deleting something.      */
6817 /* ------------------------------------------------------------------------ */
6818 static int
ipf_nat_flush_entry(ipf_main_softc_t * softc,void * entry)6819 ipf_nat_flush_entry(ipf_main_softc_t *softc, void *entry)
6820 {
6821 	ipf_nat_delete(softc, entry, NL_FLUSH);
6822 	return 0;
6823 }
6824 
6825 
6826 /* ------------------------------------------------------------------------ */
6827 /* Function:    ipf_nat_iterator                                            */
6828 /* Returns:     int - 0 == ok, else error                                   */
6829 /* Parameters:  softc(I) - pointer to soft context main structure           */
6830 /*              token(I) - pointer to ipftoken structure                    */
6831 /*              itp(I)   - pointer to ipfgeniter_t structure                */
6832 /*              obj(I)   - pointer to data description structure            */
6833 /*                                                                          */
6834 /* This function acts as a handler for the SIOCGENITER ioctls that use a    */
6835 /* generic structure to iterate through a list.  There are three different  */
6836 /* linked lists of NAT related information to go through: NAT rules, active */
6837 /* NAT mappings and the NAT fragment cache.                                 */
6838 /* ------------------------------------------------------------------------ */
6839 static int
ipf_nat_iterator(ipf_main_softc_t * softc,ipftoken_t * token,ipfgeniter_t * itp,ipfobj_t * obj)6840 ipf_nat_iterator(ipf_main_softc_t *softc, ipftoken_t *token, ipfgeniter_t *itp,
6841     ipfobj_t *obj)
6842 {
6843 	int error;
6844 
6845 	if (itp->igi_data == NULL) {
6846 		IPFERROR(60052);
6847 		return EFAULT;
6848 	}
6849 
6850 	switch (itp->igi_type)
6851 	{
6852 	case IPFGENITER_HOSTMAP :
6853 	case IPFGENITER_IPNAT :
6854 	case IPFGENITER_NAT :
6855 		error = ipf_nat_getnext(softc, token, itp, obj);
6856 		break;
6857 
6858 	case IPFGENITER_NATFRAG :
6859 		error = ipf_frag_nat_next(softc, token, itp);
6860 		break;
6861 	default :
6862 		IPFERROR(60053);
6863 		error = EINVAL;
6864 		break;
6865 	}
6866 
6867 	return error;
6868 }
6869 
6870 
6871 /* ------------------------------------------------------------------------ */
6872 /* Function:    ipf_nat_setpending                                          */
6873 /* Returns:     Nil                                                         */
6874 /* Parameters:  softc(I) - pointer to soft context main structure           */
6875 /*              nat(I)   - pointer to NAT structure                         */
6876 /* Locks:       ipf_nat (read or write)                                     */
6877 /*                                                                          */
6878 /* Put the NAT entry on to the pending queue - this queue has a very short  */
6879 /* lifetime where items are put that can't be deleted straight away because */
6880 /* of locking issues but we want to delete them ASAP, anyway.  In calling   */
6881 /* this function, it is assumed that the owner (if there is one, as shown   */
6882 /* by nat_me) is no longer interested in it.                                */
6883 /* ------------------------------------------------------------------------ */
6884 void
ipf_nat_setpending(ipf_main_softc_t * softc,nat_t * nat)6885 ipf_nat_setpending(ipf_main_softc_t *softc, nat_t *nat)
6886 {
6887 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
6888 	ipftq_t *oifq;
6889 
6890 	oifq = nat->nat_tqe.tqe_ifq;
6891 	if (oifq != NULL)
6892 		ipf_movequeue(softc->ipf_ticks, &nat->nat_tqe, oifq,
6893 			      &softn->ipf_nat_pending);
6894 	else
6895 		ipf_queueappend(softc->ipf_ticks, &nat->nat_tqe,
6896 				&softn->ipf_nat_pending, nat);
6897 
6898 	if (nat->nat_me != NULL) {
6899 		*nat->nat_me = NULL;
6900 		nat->nat_me = NULL;
6901 		nat->nat_ref--;
6902 		ASSERT(nat->nat_ref >= 0);
6903 	}
6904 }
6905 
6906 
6907 /* ------------------------------------------------------------------------ */
6908 /* Function:    nat_newrewrite                                              */
6909 /* Returns:     int - -1 == error, 0 == success (no move), 1 == success and */
6910 /*                    allow rule to be moved if IPN_ROUNDR is set.          */
6911 /* Parameters:  fin(I) - pointer to packet information                      */
6912 /*              nat(I) - pointer to NAT entry                               */
6913 /*              ni(I)  - pointer to structure with misc. information needed */
6914 /*                       to create new NAT entry.                           */
6915 /* Write Lock:  ipf_nat                                                     */
6916 /*                                                                          */
6917 /* This function is responsible for setting up an active NAT session where  */
6918 /* we are changing both the source and destination parameters at the same   */
6919 /* time.  The loop in here works differently to elsewhere - each iteration  */
6920 /* is responsible for changing a single parameter that can be incremented.  */
6921 /* So one pass may increase the source IP#, next source port, next dest. IP#*/
6922 /* and the last destination port for a total of 4 iterations to try each.   */
6923 /* This is done to try and exhaustively use the translation space available.*/
6924 /* ------------------------------------------------------------------------ */
6925 static int
ipf_nat_newrewrite(fr_info_t * fin,nat_t * nat,natinfo_t * nai)6926 ipf_nat_newrewrite(fr_info_t *fin, nat_t *nat, natinfo_t *nai)
6927 {
6928 	int src_search = 1;
6929 	int dst_search = 1;
6930 	fr_info_t frnat;
6931 	u_32_t flags;
6932 	u_short swap;
6933 	ipnat_t *np;
6934 	nat_t *natl;
6935 	int l = 0;
6936 	int changed;
6937 
6938 	natl = NULL;
6939 	changed = -1;
6940 	np = nai->nai_np;
6941 	flags = nat->nat_flags;
6942 	bcopy((char *)fin, (char *)&frnat, sizeof(*fin));
6943 
6944 	nat->nat_hm = NULL;
6945 
6946 	do {
6947 		changed = -1;
6948 		/* TRACE (l, src_search, dst_search, np) */
6949 
6950 		if ((src_search == 0) && (np->in_spnext == 0) &&
6951 		    (dst_search == 0) && (np->in_dpnext == 0)) {
6952 			if (l > 0)
6953 				return -1;
6954 		}
6955 
6956 		/*
6957 		 * Find a new source address
6958 		 */
6959 		if (ipf_nat_nextaddr(fin, &np->in_nsrc, &frnat.fin_saddr,
6960 				     &frnat.fin_saddr) == -1) {
6961 			return -1;
6962 		}
6963 
6964 		if ((np->in_nsrcaddr == 0) && (np->in_nsrcmsk == 0xffffffff)) {
6965 			src_search = 0;
6966 			if (np->in_stepnext == 0)
6967 				np->in_stepnext = 1;
6968 
6969 		} else if ((np->in_nsrcaddr == 0) && (np->in_nsrcmsk == 0)) {
6970 			src_search = 0;
6971 			if (np->in_stepnext == 0)
6972 				np->in_stepnext = 1;
6973 
6974 		} else if (np->in_nsrcmsk == 0xffffffff) {
6975 			src_search = 0;
6976 			if (np->in_stepnext == 0)
6977 				np->in_stepnext = 1;
6978 
6979 		} else if (np->in_nsrcmsk != 0xffffffff) {
6980 			if (np->in_stepnext == 0 && changed == -1) {
6981 				np->in_snip++;
6982 				np->in_stepnext++;
6983 				changed = 0;
6984 			}
6985 		}
6986 
6987 		if ((flags & IPN_TCPUDPICMP) != 0) {
6988 			if (np->in_spnext != 0)
6989 				frnat.fin_data[0] = np->in_spnext;
6990 
6991 			/*
6992 			 * Standard port translation.  Select next port.
6993 			 */
6994 			if ((flags & IPN_FIXEDSPORT) != 0) {
6995 				np->in_stepnext = 2;
6996 			} else if ((np->in_stepnext == 1) &&
6997 				   (changed == -1) && (natl != NULL)) {
6998 				np->in_spnext++;
6999 				np->in_stepnext++;
7000 				changed = 1;
7001 				if (np->in_spnext > np->in_spmax)
7002 					np->in_spnext = np->in_spmin;
7003 			}
7004 		} else {
7005 			np->in_stepnext = 2;
7006 		}
7007 		np->in_stepnext &= 0x3;
7008 
7009 		/*
7010 		 * Find a new destination address
7011 		 */
7012 		/* TRACE (fin, np, l, frnat) */
7013 
7014 		if (ipf_nat_nextaddr(fin, &np->in_ndst, &frnat.fin_daddr,
7015 				     &frnat.fin_daddr) == -1)
7016 			return -1;
7017 		if ((np->in_ndstaddr == 0) && (np->in_ndstmsk == 0xffffffff)) {
7018 			dst_search = 0;
7019 			if (np->in_stepnext == 2)
7020 				np->in_stepnext = 3;
7021 
7022 		} else if ((np->in_ndstaddr == 0) && (np->in_ndstmsk == 0)) {
7023 			dst_search = 0;
7024 			if (np->in_stepnext == 2)
7025 				np->in_stepnext = 3;
7026 
7027 		} else if (np->in_ndstmsk == 0xffffffff) {
7028 			dst_search = 0;
7029 			if (np->in_stepnext == 2)
7030 				np->in_stepnext = 3;
7031 
7032 		} else if (np->in_ndstmsk != 0xffffffff) {
7033 			if ((np->in_stepnext == 2) && (changed == -1) &&
7034 			    (natl != NULL)) {
7035 				changed = 2;
7036 				np->in_stepnext++;
7037 				np->in_dnip++;
7038 			}
7039 		}
7040 
7041 		if ((flags & IPN_TCPUDPICMP) != 0) {
7042 			if (np->in_dpnext != 0)
7043 				frnat.fin_data[1] = np->in_dpnext;
7044 
7045 			/*
7046 			 * Standard port translation.  Select next port.
7047 			 */
7048 			if ((flags & IPN_FIXEDDPORT) != 0) {
7049 				np->in_stepnext = 0;
7050 			} else if (np->in_stepnext == 3 && changed == -1) {
7051 				np->in_dpnext++;
7052 				np->in_stepnext++;
7053 				changed = 3;
7054 				if (np->in_dpnext > np->in_dpmax)
7055 					np->in_dpnext = np->in_dpmin;
7056 			}
7057 		} else {
7058 			if (np->in_stepnext == 3)
7059 				np->in_stepnext = 0;
7060 		}
7061 
7062 		/* TRACE (frnat) */
7063 
7064 		/*
7065 		 * Here we do a lookup of the connection as seen from
7066 		 * the outside.  If an IP# pair already exists, try
7067 		 * again.  So if you have A->B becomes C->B, you can
7068 		 * also have D->E become C->E but not D->B causing
7069 		 * another C->B.  Also take protocol and ports into
7070 		 * account when determining whether a pre-existing
7071 		 * NAT setup will cause an external conflict where
7072 		 * this is appropriate.
7073 		 *
7074 		 * fin_data[] is swapped around because we are doing a
7075 		 * lookup of the packet is if it were moving in the opposite
7076 		 * direction of the one we are working with now.
7077 		 */
7078 		if (flags & IPN_TCPUDP) {
7079 			swap = frnat.fin_data[0];
7080 			frnat.fin_data[0] = frnat.fin_data[1];
7081 			frnat.fin_data[1] = swap;
7082 		}
7083 		if (fin->fin_out == 1) {
7084 			natl = ipf_nat_inlookup(&frnat,
7085 						flags & ~(SI_WILDP|NAT_SEARCH),
7086 						(u_int)frnat.fin_p,
7087 						frnat.fin_dst, frnat.fin_src);
7088 
7089 		} else {
7090 			natl = ipf_nat_outlookup(&frnat,
7091 						 flags & ~(SI_WILDP|NAT_SEARCH),
7092 						 (u_int)frnat.fin_p,
7093 						 frnat.fin_dst, frnat.fin_src);
7094 		}
7095 		if (flags & IPN_TCPUDP) {
7096 			swap = frnat.fin_data[0];
7097 			frnat.fin_data[0] = frnat.fin_data[1];
7098 			frnat.fin_data[1] = swap;
7099 		}
7100 
7101 		/* TRACE natl, in_stepnext, l */
7102 
7103 		if ((natl != NULL) && (l > 8))	/* XXX 8 is arbitrary */
7104 			return -1;
7105 
7106 		np->in_stepnext &= 0x3;
7107 
7108 		l++;
7109 		changed = -1;
7110 	} while (natl != NULL);
7111 
7112 	nat->nat_osrcip = fin->fin_src;
7113 	nat->nat_odstip = fin->fin_dst;
7114 	nat->nat_nsrcip = frnat.fin_src;
7115 	nat->nat_ndstip = frnat.fin_dst;
7116 
7117 	if ((flags & IPN_TCPUDP) != 0) {
7118 		nat->nat_osport = htons(fin->fin_data[0]);
7119 		nat->nat_odport = htons(fin->fin_data[1]);
7120 		nat->nat_nsport = htons(frnat.fin_data[0]);
7121 		nat->nat_ndport = htons(frnat.fin_data[1]);
7122 	} else if ((flags & IPN_ICMPQUERY) != 0) {
7123 		nat->nat_oicmpid = fin->fin_data[1];
7124 		nat->nat_nicmpid = frnat.fin_data[1];
7125 	}
7126 
7127 	return 0;
7128 }
7129 
7130 
7131 /* ------------------------------------------------------------------------ */
7132 /* Function:    nat_newdivert                                               */
7133 /* Returns:     int - -1 == error, 0 == success                             */
7134 /* Parameters:  fin(I) - pointer to packet information                      */
7135 /*              nat(I) - pointer to NAT entry                               */
7136 /*              ni(I)  - pointer to structure with misc. information needed */
7137 /*                       to create new NAT entry.                           */
7138 /* Write Lock:  ipf_nat                                                     */
7139 /*                                                                          */
7140 /* Create a new NAT  divert session as defined by the NAT rule.  This is    */
7141 /* somewhat different to other NAT session creation routines because we     */
7142 /* do not iterate through either port numbers or IP addresses, searching    */
7143 /* for a unique mapping, however, a complimentary duplicate check is made.  */
7144 /* ------------------------------------------------------------------------ */
7145 static int
ipf_nat_newdivert(fr_info_t * fin,nat_t * nat,natinfo_t * nai)7146 ipf_nat_newdivert(fr_info_t *fin, nat_t *nat, natinfo_t *nai)
7147 {
7148 	ipf_main_softc_t *softc = fin->fin_main_soft;
7149 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
7150 	fr_info_t frnat;
7151 	ipnat_t *np;
7152 	nat_t *natl;
7153 	int p;
7154 
7155 	np = nai->nai_np;
7156 	bcopy((char *)fin, (char *)&frnat, sizeof(*fin));
7157 
7158 	nat->nat_pr[0] = 0;
7159 	nat->nat_osrcaddr = fin->fin_saddr;
7160 	nat->nat_odstaddr = fin->fin_daddr;
7161 	frnat.fin_saddr = htonl(np->in_snip);
7162 	frnat.fin_daddr = htonl(np->in_dnip);
7163 	if ((nat->nat_flags & IPN_TCPUDP) != 0) {
7164 		nat->nat_osport = htons(fin->fin_data[0]);
7165 		nat->nat_odport = htons(fin->fin_data[1]);
7166 	} else if ((nat->nat_flags & IPN_ICMPQUERY) != 0) {
7167 		nat->nat_oicmpid = fin->fin_data[1];
7168 	}
7169 
7170 	if (np->in_redir & NAT_DIVERTUDP) {
7171 		frnat.fin_data[0] = np->in_spnext;
7172 		frnat.fin_data[1] = np->in_dpnext;
7173 		frnat.fin_flx |= FI_TCPUDP;
7174 		p = IPPROTO_UDP;
7175 	} else {
7176 		frnat.fin_flx &= ~FI_TCPUDP;
7177 		p = IPPROTO_IPIP;
7178 	}
7179 
7180 	if (fin->fin_out == 1) {
7181 		natl = ipf_nat_inlookup(&frnat, 0, p,
7182 					frnat.fin_dst, frnat.fin_src);
7183 
7184 	} else {
7185 		natl = ipf_nat_outlookup(&frnat, 0, p,
7186 					 frnat.fin_dst, frnat.fin_src);
7187 	}
7188 
7189 	if (natl != NULL) {
7190 		NBUMPSIDED(fin->fin_out, ns_divert_exist);
7191 		return -1;
7192 	}
7193 
7194 	nat->nat_nsrcaddr = frnat.fin_saddr;
7195 	nat->nat_ndstaddr = frnat.fin_daddr;
7196 	if ((nat->nat_flags & IPN_TCPUDP) != 0) {
7197 		nat->nat_nsport = htons(frnat.fin_data[0]);
7198 		nat->nat_ndport = htons(frnat.fin_data[1]);
7199 	} else if ((nat->nat_flags & IPN_ICMPQUERY) != 0) {
7200 		nat->nat_nicmpid = frnat.fin_data[1];
7201 	}
7202 
7203 	nat->nat_pr[fin->fin_out] = fin->fin_p;
7204 	nat->nat_pr[1 - fin->fin_out] = p;
7205 
7206 	if (np->in_redir & NAT_REDIRECT)
7207 		nat->nat_dir = NAT_DIVERTIN;
7208 	else
7209 		nat->nat_dir = NAT_DIVERTOUT;
7210 
7211 	return 0;
7212 }
7213 
7214 
7215 /* ------------------------------------------------------------------------ */
7216 /* Function:    nat_builddivertmp                                           */
7217 /* Returns:     int - -1 == error, 0 == success                             */
7218 /* Parameters:  softn(I) - pointer to NAT context structure                 */
7219 /*              np(I)    - pointer to a NAT rule                            */
7220 /*                                                                          */
7221 /* For divert rules, a skeleton packet representing what will be prepended  */
7222 /* to the real packet is created.  Even though we don't have the full       */
7223 /* packet here, a checksum is calculated that we update later when we       */
7224 /* fill in the final details.  At present a 0 checksum for UDP is being set */
7225 /* here because it is expected that divert will be used for localhost.      */
7226 /* ------------------------------------------------------------------------ */
7227 static int
ipf_nat_builddivertmp(ipf_nat_softc_t * softn,ipnat_t * np)7228 ipf_nat_builddivertmp(ipf_nat_softc_t *softn, ipnat_t *np)
7229 {
7230 	udphdr_t *uh;
7231 	size_t len;
7232 	ip_t *ip;
7233 
7234 	if ((np->in_redir & NAT_DIVERTUDP) != 0)
7235 		len = sizeof(ip_t) + sizeof(udphdr_t);
7236 	else
7237 		len = sizeof(ip_t);
7238 
7239 	ALLOC_MB_T(np->in_divmp, len);
7240 	if (np->in_divmp == NULL) {
7241 		NBUMPD(ipf_nat_stats, ns_divert_build);
7242 		return -1;
7243 	}
7244 
7245 	/*
7246 	 * First, the header to get the packet diverted to the new destination
7247 	 */
7248 	ip = MTOD(np->in_divmp, ip_t *);
7249 	IP_V_A(ip, 4);
7250 	IP_HL_A(ip, 5);
7251 	ip->ip_tos = 0;
7252 	if ((np->in_redir & NAT_DIVERTUDP) != 0)
7253 		ip->ip_p = IPPROTO_UDP;
7254 	else
7255 		ip->ip_p = IPPROTO_IPIP;
7256 	ip->ip_ttl = 255;
7257 	ip->ip_off = 0;
7258 	ip->ip_sum = 0;
7259 	ip->ip_len = htons(len);
7260 	ip->ip_id = 0;
7261 	ip->ip_src.s_addr = htonl(np->in_snip);
7262 	ip->ip_dst.s_addr = htonl(np->in_dnip);
7263 	ip->ip_sum = ipf_cksum((u_short *)ip, sizeof(*ip));
7264 
7265 	if (np->in_redir & NAT_DIVERTUDP) {
7266 		uh = (udphdr_t *)(ip + 1);
7267 		uh->uh_sum = 0;
7268 		uh->uh_ulen = 8;
7269 		uh->uh_sport = htons(np->in_spnext);
7270 		uh->uh_dport = htons(np->in_dpnext);
7271 	}
7272 
7273 	return 0;
7274 }
7275 
7276 
7277 #define	MINDECAP	(sizeof(ip_t) + sizeof(udphdr_t) + sizeof(ip_t))
7278 
7279 /* ------------------------------------------------------------------------ */
7280 /* Function:    nat_decap                                                   */
7281 /* Returns:     int - -1 == error, 0 == success                             */
7282 /* Parameters:  fin(I) - pointer to packet information                      */
7283 /*              nat(I) - pointer to current NAT session                     */
7284 /*                                                                          */
7285 /* This function is responsible for undoing a packet's encapsulation in the */
7286 /* reverse of an encap/divert rule.  After removing the outer encapsulation */
7287 /* it is necessary to call ipf_makefrip() again so that the contents of 'fin'*/
7288 /* match the "new" packet as it may still be used by IPFilter elsewhere.    */
7289 /* We use "dir" here as the basis for some of the expectations about the    */
7290 /* outer header.  If we return an error, the goal is to leave the original  */
7291 /* packet information undisturbed - this falls short at the end where we'd  */
7292 /* need to back a backup copy of "fin" - expensive.                         */
7293 /* ------------------------------------------------------------------------ */
7294 static int
ipf_nat_decap(fr_info_t * fin,nat_t * nat)7295 ipf_nat_decap(fr_info_t *fin, nat_t *nat)
7296 {
7297 	ipf_main_softc_t *softc = fin->fin_main_soft;
7298 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
7299 	char *hdr;
7300 	int hlen;
7301 	int skip;
7302 	mb_t *m;
7303 
7304 	if ((fin->fin_flx & FI_ICMPERR) != 0) {
7305 		/*
7306 		 * ICMP packets don't get decapsulated, instead what we need
7307 		 * to do is change the ICMP reply from including (in the data
7308 		 * portion for errors) the encapsulated packet that we sent
7309 		 * out to something that resembles the original packet prior
7310 		 * to encapsulation.  This isn't done here - all we're doing
7311 		 * here is changing the outer address to ensure that it gets
7312 		 * targetted back to the correct system.
7313 		 */
7314 
7315 		if (nat->nat_dir & NAT_OUTBOUND) {
7316 			u_32_t sum1, sum2, sumd;
7317 
7318 			sum1 = ntohl(fin->fin_daddr);
7319 			sum2 = ntohl(nat->nat_osrcaddr);
7320 			CALC_SUMD(sum1, sum2, sumd);
7321 			fin->fin_ip->ip_dst = nat->nat_osrcip;
7322 			fin->fin_daddr = nat->nat_osrcaddr;
7323 #if !defined(_KERNEL) || defined(MENTAT) || defined(__sgi) || \
7324      defined(__osf__) || defined(linux)
7325 			ipf_fix_outcksum(0, &fin->fin_ip->ip_sum, sumd, 0);
7326 #endif
7327 		}
7328 		return 0;
7329 	}
7330 
7331 	m = fin->fin_m;
7332 	skip = fin->fin_hlen;
7333 
7334 	switch (nat->nat_dir)
7335 	{
7336 	case NAT_DIVERTIN :
7337 	case NAT_DIVERTOUT :
7338 		if (fin->fin_plen < MINDECAP)
7339 			return -1;
7340 		skip += sizeof(udphdr_t);
7341 		break;
7342 
7343 	case NAT_ENCAPIN :
7344 	case NAT_ENCAPOUT :
7345 		if (fin->fin_plen < (skip + sizeof(ip_t)))
7346 			return -1;
7347 		break;
7348 	default :
7349 		return -1;
7350 		/* NOTREACHED */
7351 	}
7352 
7353 	/*
7354 	 * The aim here is to keep the original packet details in "fin" for
7355 	 * as long as possible so that returning with an error is for the
7356 	 * original packet and there is little undoing work to do.
7357 	 */
7358 	if (M_LEN(m) < skip + sizeof(ip_t)) {
7359 		if (ipf_pr_pullup(fin, skip + sizeof(ip_t)) == -1)
7360 			return -1;
7361 	}
7362 
7363 	hdr = MTOD(fin->fin_m, char *);
7364 	fin->fin_ip = (ip_t *)(hdr + skip);
7365 	hlen = IP_HL(fin->fin_ip) << 2;
7366 
7367 	if (ipf_pr_pullup(fin, skip + hlen) == -1) {
7368 		NBUMPSIDED(fin->fin_out, ns_decap_pullup);
7369 		return -1;
7370 	}
7371 
7372 	fin->fin_hlen = hlen;
7373 	fin->fin_dlen -= skip;
7374 	fin->fin_plen -= skip;
7375 	fin->fin_ipoff += skip;
7376 
7377 	if (ipf_makefrip(hlen, (ip_t *)hdr, fin) == -1) {
7378 		NBUMPSIDED(fin->fin_out, ns_decap_bad);
7379 		return -1;
7380 	}
7381 
7382 	return skip;
7383 }
7384 
7385 
7386 /* ------------------------------------------------------------------------ */
7387 /* Function:    nat_nextaddr                                                */
7388 /* Returns:     int - -1 == bad input (no new address),                     */
7389 /*                     0 == success and dst has new address                 */
7390 /* Parameters:  fin(I) - pointer to packet information                      */
7391 /*              na(I)  - how to generate new address                        */
7392 /*              old(I) - original address being replaced                    */
7393 /*              dst(O) - where to put the new address                       */
7394 /* Write Lock:  ipf_nat                                                     */
7395 /*                                                                          */
7396 /* This function uses the contents of the "na" structure, in combination    */
7397 /* with "old" to produce a new address to store in "dst".  Not all of the   */
7398 /* possible uses of "na" will result in a new address.                      */
7399 /* ------------------------------------------------------------------------ */
7400 static int
ipf_nat_nextaddr(fr_info_t * fin,nat_addr_t * na,u_32_t * old,u_32_t * dst)7401 ipf_nat_nextaddr(fr_info_t *fin, nat_addr_t *na, u_32_t *old, u_32_t *dst)
7402 {
7403 	ipf_main_softc_t *softc = fin->fin_main_soft;
7404 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
7405 	u_32_t amin, amax, new;
7406 	i6addr_t newip;
7407 	int error;
7408 
7409 	new = 0;
7410 	amin = na->na_addr[0].in4.s_addr;
7411 
7412 	switch (na->na_atype)
7413 	{
7414 	case FRI_RANGE :
7415 		amax = na->na_addr[1].in4.s_addr;
7416 		break;
7417 
7418 	case FRI_NETMASKED :
7419 	case FRI_DYNAMIC :
7420 	case FRI_NORMAL :
7421 		/*
7422 		 * Compute the maximum address by adding the inverse of the
7423 		 * netmask to the minimum address.
7424 		 */
7425 		amax = ~na->na_addr[1].in4.s_addr;
7426 		amax |= amin;
7427 		break;
7428 
7429 	case FRI_LOOKUP :
7430 		break;
7431 
7432 	case FRI_BROADCAST :
7433 	case FRI_PEERADDR :
7434 	case FRI_NETWORK :
7435 	default :
7436 		return -1;
7437 	}
7438 
7439 	error = -1;
7440 
7441 	if (na->na_atype == FRI_LOOKUP) {
7442 		if (na->na_type == IPLT_DSTLIST) {
7443 			error = ipf_dstlist_select_node(fin, na->na_ptr, dst,
7444 							NULL);
7445 		} else {
7446 			NBUMPSIDE(fin->fin_out, ns_badnextaddr);
7447 		}
7448 
7449 	} else if (na->na_atype == IPLT_NONE) {
7450 		/*
7451 		 * 0/0 as the new address means leave it alone.
7452 		 */
7453 		if (na->na_addr[0].in4.s_addr == 0 &&
7454 		    na->na_addr[1].in4.s_addr == 0) {
7455 			new = *old;
7456 
7457 		/*
7458 		 * 0/32 means get the interface's address
7459 		 */
7460 		} else if (na->na_addr[0].in4.s_addr == 0 &&
7461 			   na->na_addr[1].in4.s_addr == 0xffffffff) {
7462 			if (ipf_ifpaddr(softc, 4, na->na_atype,
7463 					fin->fin_ifp, &newip, NULL) == -1) {
7464 				NBUMPSIDED(fin->fin_out, ns_ifpaddrfail);
7465 				return -1;
7466 			}
7467 			new = newip.in4.s_addr;
7468 		} else {
7469 			new = htonl(na->na_nextip);
7470 		}
7471 		*dst = new;
7472 		error = 0;
7473 
7474 	} else {
7475 		NBUMPSIDE(fin->fin_out, ns_badnextaddr);
7476 	}
7477 
7478 	return error;
7479 }
7480 
7481 
7482 /* ------------------------------------------------------------------------ */
7483 /* Function:    nat_nextaddrinit                                            */
7484 /* Returns:     int - 0 == success, else error number                       */
7485 /* Parameters:  softc(I) - pointer to soft context main structure           */
7486 /*              na(I)      - NAT address information for generating new addr*/
7487 /*              initial(I) - flag indicating if it is the first call for    */
7488 /*                           this "na" structure.                           */
7489 /*              ifp(I)     - network interface to derive address            */
7490 /*                           information from.                              */
7491 /*                                                                          */
7492 /* This function is expected to be called in two scenarious: when a new NAT */
7493 /* rule is loaded into the kernel and when the list of NAT rules is sync'd  */
7494 /* up with the valid network interfaces (possibly due to them changing.)    */
7495 /* To distinguish between these, the "initial" parameter is used.  If it is */
7496 /* 1 then this indicates the rule has just been reloaded and 0 for when we  */
7497 /* are updating information.  This difference is important because in       */
7498 /* instances where we are not updating address information associated with  */
7499 /* a network interface, we don't want to disturb what the "next" address to */
7500 /* come out of ipf_nat_nextaddr() will be.                                  */
7501 /* ------------------------------------------------------------------------ */
7502 static int
ipf_nat_nextaddrinit(ipf_main_softc_t * softc,char * base,nat_addr_t * na,int initial,void * ifp)7503 ipf_nat_nextaddrinit(ipf_main_softc_t *softc, char *base, nat_addr_t *na,
7504     int initial, void *ifp)
7505 {
7506 
7507 	switch (na->na_atype)
7508 	{
7509 	case FRI_LOOKUP :
7510 		if (na->na_subtype == 0) {
7511 			na->na_ptr = ipf_lookup_res_num(softc, IPL_LOGNAT,
7512 							na->na_type,
7513 							na->na_num,
7514 							&na->na_func);
7515 		} else if (na->na_subtype == 1) {
7516 			na->na_ptr = ipf_lookup_res_name(softc, IPL_LOGNAT,
7517 							 na->na_type,
7518 							 base + na->na_num,
7519 							 &na->na_func);
7520 		}
7521 		if (na->na_func == NULL) {
7522 			IPFERROR(60060);
7523 			return ESRCH;
7524 		}
7525 		if (na->na_ptr == NULL) {
7526 			IPFERROR(60056);
7527 			return ESRCH;
7528 		}
7529 		break;
7530 
7531 	case FRI_DYNAMIC :
7532 	case FRI_BROADCAST :
7533 	case FRI_NETWORK :
7534 	case FRI_NETMASKED :
7535 	case FRI_PEERADDR :
7536 		if (ifp != NULL)
7537 			(void )ipf_ifpaddr(softc, 4, na->na_atype, ifp,
7538 					   &na->na_addr[0], &na->na_addr[1]);
7539 		break;
7540 
7541 	case FRI_SPLIT :
7542 	case FRI_RANGE :
7543 		if (initial)
7544 			na->na_nextip = ntohl(na->na_addr[0].in4.s_addr);
7545 		break;
7546 
7547 	case FRI_NONE :
7548 		na->na_addr[0].in4.s_addr &= na->na_addr[1].in4.s_addr;
7549 		return 0;
7550 
7551 	case FRI_NORMAL :
7552 		na->na_addr[0].in4.s_addr &= na->na_addr[1].in4.s_addr;
7553 		break;
7554 
7555 	default :
7556 		IPFERROR(60054);
7557 		return EINVAL;
7558 	}
7559 
7560 	if (initial && (na->na_atype == FRI_NORMAL)) {
7561 		if (na->na_addr[0].in4.s_addr == 0) {
7562 			if ((na->na_addr[1].in4.s_addr == 0xffffffff) ||
7563 			    (na->na_addr[1].in4.s_addr == 0)) {
7564 				return 0;
7565 			}
7566 		}
7567 
7568 		if (na->na_addr[1].in4.s_addr == 0xffffffff) {
7569 			na->na_nextip = ntohl(na->na_addr[0].in4.s_addr);
7570 		} else {
7571 			na->na_nextip = ntohl(na->na_addr[0].in4.s_addr) + 1;
7572 		}
7573 	}
7574 
7575 	return 0;
7576 }
7577 
7578 
7579 /* ------------------------------------------------------------------------ */
7580 /* Function:    ipf_nat_matchflush                                          */
7581 /* Returns:     int - -1 == error, 0 == success                             */
7582 /* Parameters:  softc(I) - pointer to soft context main structure           */
7583 /*              softn(I) - pointer to NAT context structure                 */
7584 /*              nat(I)   - pointer to current NAT session                   */
7585 /*                                                                          */
7586 /* ------------------------------------------------------------------------ */
7587 static int
ipf_nat_matchflush(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,void * data)7588 ipf_nat_matchflush(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, void *data)
7589 {
7590 	int *array, flushed, error;
7591 	nat_t *nat, *natnext;
7592 	ipfobj_t obj;
7593 
7594 	error = ipf_matcharray_load(softc, data, &obj, &array);
7595 	if (error != 0)
7596 		return error;
7597 
7598 	flushed = 0;
7599 
7600 	for (nat = softn->ipf_nat_instances; nat != NULL; nat = natnext) {
7601 		natnext = nat->nat_next;
7602 		if (ipf_nat_matcharray(nat, array, softc->ipf_ticks) == 0) {
7603 			ipf_nat_delete(softc, nat, NL_FLUSH);
7604 			flushed++;
7605 		}
7606 	}
7607 
7608 	obj.ipfo_retval = flushed;
7609 	error = BCOPYOUT(&obj, data, sizeof(obj));
7610 
7611 	KFREES(array, array[0] * sizeof(*array));
7612 
7613 	return error;
7614 }
7615 
7616 
7617 /* ------------------------------------------------------------------------ */
7618 /* Function:    ipf_nat_matcharray                                          */
7619 /* Returns:     int - -1 == error, 0 == success                             */
7620 /* Parameters:  fin(I) - pointer to packet information                      */
7621 /*              nat(I) - pointer to current NAT session                     */
7622 /*                                                                          */
7623 /* ------------------------------------------------------------------------ */
7624 static int
ipf_nat_matcharray(nat_t * nat,int * array,u_long ticks)7625 ipf_nat_matcharray(nat_t *nat, int *array, u_long ticks)
7626 {
7627 	int i, n, *x, e, p;
7628 
7629 	e = 0;
7630 	n = array[0];
7631 	x = array + 1;
7632 
7633 	for (; n > 0; x += 3 + x[2]) {
7634 		if (x[0] == IPF_EXP_END)
7635 			break;
7636 		e = 0;
7637 
7638 		n -= x[2] + 3;
7639 		if (n < 0)
7640 			break;
7641 
7642 		p = x[0] >> 16;
7643 		if (p != 0 && p != nat->nat_pr[1])
7644 			break;
7645 
7646 		switch (x[0])
7647 		{
7648 		case IPF_EXP_IP_PR :
7649 			for (i = 0; !e && i < x[2]; i++) {
7650 				e |= (nat->nat_pr[1] == x[i + 3]);
7651 			}
7652 			break;
7653 
7654 		case IPF_EXP_IP_SRCADDR :
7655 			if (nat->nat_v[0] == 4) {
7656 				for (i = 0; !e && i < x[2]; i++) {
7657 					e |= ((nat->nat_osrcaddr & x[i + 4]) ==
7658 					      x[i + 3]);
7659 				}
7660 			}
7661 			if (nat->nat_v[1] == 4) {
7662 				for (i = 0; !e && i < x[2]; i++) {
7663 					e |= ((nat->nat_nsrcaddr & x[i + 4]) ==
7664 					      x[i + 3]);
7665 				}
7666 			}
7667 			break;
7668 
7669 		case IPF_EXP_IP_DSTADDR :
7670 			if (nat->nat_v[0] == 4) {
7671 				for (i = 0; !e && i < x[2]; i++) {
7672 					e |= ((nat->nat_odstaddr & x[i + 4]) ==
7673 					      x[i + 3]);
7674 				}
7675 			}
7676 			if (nat->nat_v[1] == 4) {
7677 				for (i = 0; !e && i < x[2]; i++) {
7678 					e |= ((nat->nat_ndstaddr & x[i + 4]) ==
7679 					      x[i + 3]);
7680 				}
7681 			}
7682 			break;
7683 
7684 		case IPF_EXP_IP_ADDR :
7685 			for (i = 0; !e && i < x[2]; i++) {
7686 				if (nat->nat_v[0] == 4) {
7687 					e |= ((nat->nat_osrcaddr & x[i + 4]) ==
7688 					      x[i + 3]);
7689 				}
7690 				if (nat->nat_v[1] == 4) {
7691 					e |= ((nat->nat_nsrcaddr & x[i + 4]) ==
7692 					      x[i + 3]);
7693 				}
7694 				if (nat->nat_v[0] == 4) {
7695 					e |= ((nat->nat_odstaddr & x[i + 4]) ==
7696 					      x[i + 3]);
7697 				}
7698 				if (nat->nat_v[1] == 4) {
7699 					e |= ((nat->nat_ndstaddr & x[i + 4]) ==
7700 					      x[i + 3]);
7701 				}
7702 			}
7703 			break;
7704 
7705 #ifdef USE_INET6
7706 		case IPF_EXP_IP6_SRCADDR :
7707 			if (nat->nat_v[0] == 6) {
7708 				for (i = 0; !e && i < x[3]; i++) {
7709 					e |= IP6_MASKEQ(&nat->nat_osrc6,
7710 							x + i + 7, x + i + 3);
7711 				}
7712 			}
7713 			if (nat->nat_v[1] == 6) {
7714 				for (i = 0; !e && i < x[3]; i++) {
7715 					e |= IP6_MASKEQ(&nat->nat_nsrc6,
7716 							x + i + 7, x + i + 3);
7717 				}
7718 			}
7719 			break;
7720 
7721 		case IPF_EXP_IP6_DSTADDR :
7722 			if (nat->nat_v[0] == 6) {
7723 				for (i = 0; !e && i < x[3]; i++) {
7724 					e |= IP6_MASKEQ(&nat->nat_odst6,
7725 							x + i + 7,
7726 							x + i + 3);
7727 				}
7728 			}
7729 			if (nat->nat_v[1] == 6) {
7730 				for (i = 0; !e && i < x[3]; i++) {
7731 					e |= IP6_MASKEQ(&nat->nat_ndst6,
7732 							x + i + 7,
7733 							x + i + 3);
7734 				}
7735 			}
7736 			break;
7737 
7738 		case IPF_EXP_IP6_ADDR :
7739 			for (i = 0; !e && i < x[3]; i++) {
7740 				if (nat->nat_v[0] == 6) {
7741 					e |= IP6_MASKEQ(&nat->nat_osrc6,
7742 							x + i + 7,
7743 							x + i + 3);
7744 				}
7745 				if (nat->nat_v[0] == 6) {
7746 					e |= IP6_MASKEQ(&nat->nat_odst6,
7747 							x + i + 7,
7748 							x + i + 3);
7749 				}
7750 				if (nat->nat_v[1] == 6) {
7751 					e |= IP6_MASKEQ(&nat->nat_nsrc6,
7752 							x + i + 7,
7753 							x + i + 3);
7754 				}
7755 				if (nat->nat_v[1] == 6) {
7756 					e |= IP6_MASKEQ(&nat->nat_ndst6,
7757 							x + i + 7,
7758 							x + i + 3);
7759 				}
7760 			}
7761 			break;
7762 #endif
7763 
7764 		case IPF_EXP_UDP_PORT :
7765 		case IPF_EXP_TCP_PORT :
7766 			for (i = 0; !e && i < x[2]; i++) {
7767 				e |= (nat->nat_nsport == x[i + 3]) ||
7768 				     (nat->nat_ndport == x[i + 3]);
7769 			}
7770 			break;
7771 
7772 		case IPF_EXP_UDP_SPORT :
7773 		case IPF_EXP_TCP_SPORT :
7774 			for (i = 0; !e && i < x[2]; i++) {
7775 				e |= (nat->nat_nsport == x[i + 3]);
7776 			}
7777 			break;
7778 
7779 		case IPF_EXP_UDP_DPORT :
7780 		case IPF_EXP_TCP_DPORT :
7781 			for (i = 0; !e && i < x[2]; i++) {
7782 				e |= (nat->nat_ndport == x[i + 3]);
7783 			}
7784 			break;
7785 
7786 		case IPF_EXP_TCP_STATE :
7787 			for (i = 0; !e && i < x[2]; i++) {
7788 				e |= (nat->nat_tcpstate[0] == x[i + 3]) ||
7789 				     (nat->nat_tcpstate[1] == x[i + 3]);
7790 			}
7791 			break;
7792 
7793 		case IPF_EXP_IDLE_GT :
7794 			e |= (ticks - nat->nat_touched > x[3]);
7795 			break;
7796 		}
7797 		e ^= x[1];
7798 
7799 		if (!e)
7800 			break;
7801 	}
7802 
7803 	return e;
7804 }
7805 
7806 
7807 /* ------------------------------------------------------------------------ */
7808 /* Function:    ipf_nat_gettable                                            */
7809 /* Returns:     int     - 0 = success, else error                           */
7810 /* Parameters:  softc(I) - pointer to soft context main structure           */
7811 /*              softn(I) - pointer to NAT context structure                 */
7812 /*              data(I)  - pointer to ioctl data                            */
7813 /*                                                                          */
7814 /* This function handles ioctl requests for tables of nat information.      */
7815 /* At present the only table it deals with is the hash bucket statistics.   */
7816 /* ------------------------------------------------------------------------ */
7817 static int
ipf_nat_gettable(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,char * data)7818 ipf_nat_gettable(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, char *data)
7819 {
7820 	ipftable_t table;
7821 	int error;
7822 
7823 	error = ipf_inobj(softc, data, NULL, &table, IPFOBJ_GTABLE);
7824 	if (error != 0)
7825 		return error;
7826 
7827 	switch (table.ita_type)
7828 	{
7829 	case IPFTABLE_BUCKETS_NATIN :
7830 		error = COPYOUT(softn->ipf_nat_stats.ns_side[0].ns_bucketlen,
7831 				table.ita_table,
7832 				softn->ipf_nat_table_sz * sizeof(u_int));
7833 		break;
7834 
7835 	case IPFTABLE_BUCKETS_NATOUT :
7836 		error = COPYOUT(softn->ipf_nat_stats.ns_side[1].ns_bucketlen,
7837 				table.ita_table,
7838 				softn->ipf_nat_table_sz * sizeof(u_int));
7839 		break;
7840 
7841 	default :
7842 		IPFERROR(60058);
7843 		return EINVAL;
7844 	}
7845 
7846 	if (error != 0) {
7847 		IPFERROR(60059);
7848 		error = EFAULT;
7849 	}
7850 	return error;
7851 }
7852 
7853 
7854 /* ------------------------------------------------------------------------ */
7855 /* Function:    ipf_nat_settimeout                                          */
7856 /* Returns:     int  - 0 = success, else failure			    */
7857 /* Parameters:  softc(I) - pointer to soft context main structure           */
7858 /*              t(I) - pointer to tunable                                   */
7859 /*              p(I) - pointer to new tuning data                           */
7860 /*                                                                          */
7861 /* Apply the timeout change to the NAT timeout queues.                      */
7862 /* ------------------------------------------------------------------------ */
7863 int
ipf_nat_settimeout(struct ipf_main_softc_s * softc,ipftuneable_t * t,ipftuneval_t * p)7864 ipf_nat_settimeout(struct ipf_main_softc_s *softc, ipftuneable_t *t,
7865     ipftuneval_t *p)
7866 {
7867 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
7868 
7869 	if (!strncmp(t->ipft_name, "tcp_", 4))
7870 		return ipf_settimeout_tcp(t, p, softn->ipf_nat_tcptq);
7871 
7872 	if (!strcmp(t->ipft_name, "udp_timeout")) {
7873 		ipf_apply_timeout(&softn->ipf_nat_udptq, p->ipftu_int);
7874 	} else if (!strcmp(t->ipft_name, "udp_ack_timeout")) {
7875 		ipf_apply_timeout(&softn->ipf_nat_udpacktq, p->ipftu_int);
7876 	} else if (!strcmp(t->ipft_name, "icmp_timeout")) {
7877 		ipf_apply_timeout(&softn->ipf_nat_icmptq, p->ipftu_int);
7878 	} else if (!strcmp(t->ipft_name, "icmp_ack_timeout")) {
7879 		ipf_apply_timeout(&softn->ipf_nat_icmpacktq, p->ipftu_int);
7880 	} else if (!strcmp(t->ipft_name, "ip_timeout")) {
7881 		ipf_apply_timeout(&softn->ipf_nat_iptq, p->ipftu_int);
7882 	} else {
7883 		IPFERROR(60062);
7884 		return ESRCH;
7885 	}
7886 	return 0;
7887 }
7888 
7889 
7890 /* ------------------------------------------------------------------------ */
7891 /* Function:    ipf_nat_rehash                                              */
7892 /* Returns:     int  - 0 = success, else failure			    */
7893 /* Parameters:  softc(I) - pointer to soft context main structure           */
7894 /*              t(I) - pointer to tunable                                   */
7895 /*              p(I) - pointer to new tuning data                           */
7896 /*                                                                          */
7897 /* To change the size of the basic NAT table, we need to first allocate the */
7898 /* new tables (lest it fails and we've got nowhere to store all of the NAT  */
7899 /* sessions currently active) and then walk through the entire list and     */
7900 /* insert them into the table.  There are two tables here: an inbound one   */
7901 /* and an outbound one.  Each NAT entry goes into each table once.          */
7902 /* ------------------------------------------------------------------------ */
7903 int
ipf_nat_rehash(ipf_main_softc_t * softc,ipftuneable_t * t,ipftuneval_t * p)7904 ipf_nat_rehash(ipf_main_softc_t *softc, ipftuneable_t *t, ipftuneval_t *p)
7905 {
7906 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
7907 	nat_t **newtab[2], *nat, **natp;
7908 	u_int *bucketlens[2];
7909 	u_int maxbucket;
7910 	u_int newsize;
7911 	int error;
7912 	u_int hv;
7913 	int i;
7914 
7915 	newsize = p->ipftu_int;
7916 	/*
7917 	 * In case there is nothing to do...
7918 	 */
7919 	if (newsize == softn->ipf_nat_table_sz)
7920 		return 0;
7921 
7922 	newtab[0] = NULL;
7923 	newtab[1] = NULL;
7924 	bucketlens[0] = NULL;
7925 	bucketlens[1] = NULL;
7926 	/*
7927 	 * 4 tables depend on the NAT table size: the inbound looking table,
7928 	 * the outbound lookup table and the hash chain length for each.
7929 	 */
7930 	KMALLOCS(newtab[0], nat_t **, newsize * sizeof(nat_t *));
7931 	if (newtab[0] == NULL) {
7932 		error = 60063;
7933 		goto badrehash;
7934 	}
7935 
7936 	KMALLOCS(newtab[1], nat_t **, newsize * sizeof(nat_t *));
7937 	if (newtab[1] == NULL) {
7938 		error = 60064;
7939 		goto badrehash;
7940 	}
7941 
7942 	KMALLOCS(bucketlens[0], u_int *, newsize * sizeof(u_int));
7943 	if (bucketlens[0] == NULL) {
7944 		error = 60065;
7945 		goto badrehash;
7946 	}
7947 
7948 	KMALLOCS(bucketlens[1], u_int *, newsize * sizeof(u_int));
7949 	if (bucketlens[1] == NULL) {
7950 		error = 60066;
7951 		goto badrehash;
7952 	}
7953 
7954 	/*
7955 	 * Recalculate the maximum length based on the new size.
7956 	 */
7957 	for (maxbucket = 0, i = newsize; i > 0; i >>= 1)
7958 		maxbucket++;
7959 	maxbucket *= 2;
7960 
7961 	bzero((char *)newtab[0], newsize * sizeof(nat_t *));
7962 	bzero((char *)newtab[1], newsize * sizeof(nat_t *));
7963 	bzero((char *)bucketlens[0], newsize * sizeof(u_int));
7964 	bzero((char *)bucketlens[1], newsize * sizeof(u_int));
7965 
7966 	WRITE_ENTER(&softc->ipf_nat);
7967 
7968 	if (softn->ipf_nat_table[0] != NULL) {
7969 		KFREES(softn->ipf_nat_table[0],
7970 		       softn->ipf_nat_table_sz *
7971 		       sizeof(*softn->ipf_nat_table[0]));
7972 	}
7973 	softn->ipf_nat_table[0] = newtab[0];
7974 
7975 	if (softn->ipf_nat_table[1] != NULL) {
7976 		KFREES(softn->ipf_nat_table[1],
7977 		       softn->ipf_nat_table_sz *
7978 		       sizeof(*softn->ipf_nat_table[1]));
7979 	}
7980 	softn->ipf_nat_table[1] = newtab[1];
7981 
7982 	if (softn->ipf_nat_stats.ns_side[0].ns_bucketlen != NULL) {
7983 		KFREES(softn->ipf_nat_stats.ns_side[0].ns_bucketlen,
7984 		       softn->ipf_nat_table_sz * sizeof(u_int));
7985 	}
7986 	softn->ipf_nat_stats.ns_side[0].ns_bucketlen = bucketlens[0];
7987 
7988 	if (softn->ipf_nat_stats.ns_side[1].ns_bucketlen != NULL) {
7989 		KFREES(softn->ipf_nat_stats.ns_side[1].ns_bucketlen,
7990 		       softn->ipf_nat_table_sz * sizeof(u_int));
7991 	}
7992 	softn->ipf_nat_stats.ns_side[1].ns_bucketlen = bucketlens[1];
7993 
7994 	softn->ipf_nat_maxbucket = maxbucket;
7995 	softn->ipf_nat_table_sz = newsize;
7996 	/*
7997 	 * Walk through the entire list of NAT table entries and put them
7998 	 * in the new NAT table, somewhere.  Because we have a new table,
7999 	 * we need to restart the counter of how many chains are in use.
8000 	 */
8001 	softn->ipf_nat_stats.ns_side[0].ns_inuse = 0;
8002 	softn->ipf_nat_stats.ns_side[1].ns_inuse = 0;
8003 
8004 	for (nat = softn->ipf_nat_instances; nat != NULL; nat = nat->nat_next) {
8005 		nat->nat_hnext[0] = NULL;
8006 		nat->nat_phnext[0] = NULL;
8007 		hv = nat->nat_hv[0] % softn->ipf_nat_table_sz;
8008 
8009 		natp = &softn->ipf_nat_table[0][hv];
8010 		if (*natp) {
8011 			(*natp)->nat_phnext[0] = &nat->nat_hnext[0];
8012 		} else {
8013 			NBUMPSIDE(0, ns_inuse);
8014 		}
8015 		nat->nat_phnext[0] = natp;
8016 		nat->nat_hnext[0] = *natp;
8017 		*natp = nat;
8018 		NBUMPSIDE(0, ns_bucketlen[hv]);
8019 
8020 		nat->nat_hnext[1] = NULL;
8021 		nat->nat_phnext[1] = NULL;
8022 		hv = nat->nat_hv[1] % softn->ipf_nat_table_sz;
8023 
8024 		natp = &softn->ipf_nat_table[1][hv];
8025 		if (*natp) {
8026 			(*natp)->nat_phnext[1] = &nat->nat_hnext[1];
8027 		} else {
8028 			NBUMPSIDE(1, ns_inuse);
8029 		}
8030 		nat->nat_phnext[1] = natp;
8031 		nat->nat_hnext[1] = *natp;
8032 		*natp = nat;
8033 		NBUMPSIDE(1, ns_bucketlen[hv]);
8034 	}
8035 	RWLOCK_EXIT(&softc->ipf_nat);
8036 
8037 	return 0;
8038 
8039 badrehash:
8040 	if (bucketlens[1] != NULL) {
8041 		KFREES(bucketlens[0], newsize * sizeof(u_int));
8042 	}
8043 	if (bucketlens[0] != NULL) {
8044 		KFREES(bucketlens[0], newsize * sizeof(u_int));
8045 	}
8046 	if (newtab[0] != NULL) {
8047 		KFREES(newtab[0], newsize * sizeof(nat_t *));
8048 	}
8049 	if (newtab[1] != NULL) {
8050 		KFREES(newtab[1], newsize * sizeof(nat_t *));
8051 	}
8052 	IPFERROR(error);
8053 	return ENOMEM;
8054 }
8055 
8056 
8057 /* ------------------------------------------------------------------------ */
8058 /* Function:    ipf_nat_rehash_rules                                        */
8059 /* Returns:     int  - 0 = success, else failure			    */
8060 /* Parameters:  softc(I) - pointer to soft context main structure           */
8061 /*              t(I) - pointer to tunable                                   */
8062 /*              p(I) - pointer to new tuning data                           */
8063 /*                                                                          */
8064 /* All of the NAT rules hang off of a hash table that is searched with a    */
8065 /* hash on address after the netmask is applied.  There is a different table*/
8066 /* for both inbound rules (rdr) and outbound (map.)  The resizing will only */
8067 /* affect one of these two tables.                                          */
8068 /* ------------------------------------------------------------------------ */
8069 int
ipf_nat_rehash_rules(ipf_main_softc_t * softc,ipftuneable_t * t,ipftuneval_t * p)8070 ipf_nat_rehash_rules(ipf_main_softc_t *softc, ipftuneable_t *t, ipftuneval_t *p)
8071 {
8072 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
8073 	ipnat_t **newtab, *np, ***old, **npp;
8074 	u_int newsize;
8075 	u_int mask;
8076 	u_int hv;
8077 
8078 	newsize = p->ipftu_int;
8079 	/*
8080 	 * In case there is nothing to do...
8081 	 */
8082 	if (newsize == *t->ipft_pint)
8083 		return 0;
8084 
8085 	/*
8086 	 * All inbound rules have the NAT_REDIRECT bit set in in_redir and
8087 	 * all outbound rules have either NAT_MAP or MAT_MAPBLK set.
8088 	 * This if statement allows for some more generic code to be below,
8089 	 * rather than two huge gobs of code that almost do the same thing.
8090 	 */
8091 	if (t->ipft_pint == &softn->ipf_nat_rdrrules_sz) {
8092 		old = &softn->ipf_nat_rdr_rules;
8093 		mask = NAT_REDIRECT;
8094 	} else {
8095 		old = &softn->ipf_nat_map_rules;
8096 		mask = NAT_MAP|NAT_MAPBLK;
8097 	}
8098 
8099 	KMALLOCS(newtab, ipnat_t **, newsize * sizeof(ipnat_t *));
8100 	if (newtab == NULL) {
8101 		IPFERROR(60067);
8102 		return ENOMEM;
8103 	}
8104 
8105 	bzero((char *)newtab, newsize * sizeof(ipnat_t *));
8106 
8107 	WRITE_ENTER(&softc->ipf_nat);
8108 
8109 	if (*old != NULL) {
8110 		KFREES(*old, *t->ipft_pint * sizeof(ipnat_t **));
8111 	}
8112 	*old = newtab;
8113 	*t->ipft_pint = newsize;
8114 
8115 	for (np = softn->ipf_nat_list; np != NULL; np = np->in_next) {
8116 		if ((np->in_redir & mask) == 0)
8117 			continue;
8118 
8119 		if (np->in_redir & NAT_REDIRECT) {
8120 			np->in_rnext = NULL;
8121 			hv = np->in_hv[0] % newsize;
8122 			for (npp = newtab + hv; *npp != NULL; )
8123 				npp = &(*npp)->in_rnext;
8124 			np->in_prnext = npp;
8125 			*npp = np;
8126 		}
8127 		if (np->in_redir & NAT_MAP) {
8128 			np->in_mnext = NULL;
8129 			hv = np->in_hv[1] % newsize;
8130 			for (npp = newtab + hv; *npp != NULL; )
8131 				npp = &(*npp)->in_mnext;
8132 			np->in_pmnext = npp;
8133 			*npp = np;
8134 		}
8135 
8136 	}
8137 	RWLOCK_EXIT(&softc->ipf_nat);
8138 
8139 	return 0;
8140 }
8141 
8142 
8143 /* ------------------------------------------------------------------------ */
8144 /* Function:    ipf_nat_hostmap_rehash                                      */
8145 /* Returns:     int  - 0 = success, else failure			    */
8146 /* Parameters:  softc(I) - pointer to soft context main structure           */
8147 /*              t(I) - pointer to tunable                                   */
8148 /*              p(I) - pointer to new tuning data                           */
8149 /*                                                                          */
8150 /* Allocate and populate a new hash table that will contain a reference to  */
8151 /* all of the active IP# translations currently in place.                   */
8152 /* ------------------------------------------------------------------------ */
8153 int
ipf_nat_hostmap_rehash(ipf_main_softc_t * softc,ipftuneable_t * t,ipftuneval_t * p)8154 ipf_nat_hostmap_rehash(ipf_main_softc_t *softc, ipftuneable_t *t,
8155     ipftuneval_t *p)
8156 {
8157 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
8158 	hostmap_t *hm, **newtab;
8159 	u_int newsize;
8160 	u_int hv;
8161 
8162 	newsize = p->ipftu_int;
8163 	/*
8164 	 * In case there is nothing to do...
8165 	 */
8166 	if (newsize == *t->ipft_pint)
8167 		return 0;
8168 
8169 	KMALLOCS(newtab, hostmap_t **, newsize * sizeof(hostmap_t *));
8170 	if (newtab == NULL) {
8171 		IPFERROR(60068);
8172 		return ENOMEM;
8173 	}
8174 
8175 	bzero((char *)newtab, newsize * sizeof(hostmap_t *));
8176 
8177 	WRITE_ENTER(&softc->ipf_nat);
8178 	if (softn->ipf_hm_maptable != NULL) {
8179 		KFREES(softn->ipf_hm_maptable,
8180 		       softn->ipf_nat_hostmap_sz * sizeof(hostmap_t *));
8181 	}
8182 	softn->ipf_hm_maptable = newtab;
8183 	softn->ipf_nat_hostmap_sz = newsize;
8184 
8185 	for (hm = softn->ipf_hm_maplist; hm != NULL; hm = hm->hm_next) {
8186 		hv = hm->hm_hv % softn->ipf_nat_hostmap_sz;
8187 		hm->hm_hnext = softn->ipf_hm_maptable[hv];
8188 		hm->hm_phnext = softn->ipf_hm_maptable + hv;
8189 		if (softn->ipf_hm_maptable[hv] != NULL)
8190 			softn->ipf_hm_maptable[hv]->hm_phnext = &hm->hm_hnext;
8191 		softn->ipf_hm_maptable[hv] = hm;
8192 	}
8193 	RWLOCK_EXIT(&softc->ipf_nat);
8194 
8195 	return 0;
8196 }
8197 
8198 
8199 /* ------------------------------------------------------------------------ */
8200 /* Function:    ipf_nat_add_tq                                              */
8201 /* Parameters:  softc(I) - pointer to soft context main structure           */
8202 /*                                                                          */
8203 /* ------------------------------------------------------------------------ */
8204 ipftq_t *
ipf_nat_add_tq(ipf_main_softc_t * softc,int ttl)8205 ipf_nat_add_tq(ipf_main_softc_t *softc, int ttl)
8206 {
8207 	ipf_nat_softc_t *softs = softc->ipf_nat_soft;
8208 
8209 	return ipf_addtimeoutqueue(softc, &softs->ipf_nat_utqe, ttl);
8210 }
8211 
8212 /* ------------------------------------------------------------------------ */
8213 /* Function:    ipf_nat_uncreate                                            */
8214 /* Returns:     Nil                                                         */
8215 /* Parameters:  fin(I) - pointer to packet information                      */
8216 /*                                                                          */
8217 /* This function is used to remove a NAT entry from the NAT table when we   */
8218 /* decide that the create was actually in error. It is thus assumed that    */
8219 /* fin_flx will have both FI_NATED and FI_NATNEW set. Because we're dealing */
8220 /* with the translated packet (not the original), we have to reverse the    */
8221 /* lookup. Although doing the lookup is expensive (relatively speaking), it */
8222 /* is not anticipated that this will be a frequent occurance for normal     */
8223 /* traffic patterns.                                                        */
8224 /* ------------------------------------------------------------------------ */
8225 void
ipf_nat_uncreate(fr_info_t * fin)8226 ipf_nat_uncreate(fr_info_t *fin)
8227 {
8228 	ipf_main_softc_t *softc = fin->fin_main_soft;
8229 	ipf_nat_softc_t *softn = softc->ipf_nat_soft;
8230 	int nflags;
8231 	nat_t *nat;
8232 
8233 	switch (fin->fin_p)
8234 	{
8235 	case IPPROTO_TCP :
8236 		nflags = IPN_TCP;
8237 		break;
8238 	case IPPROTO_UDP :
8239 		nflags = IPN_UDP;
8240 		break;
8241 	default :
8242 		nflags = 0;
8243 		break;
8244 	}
8245 
8246 	WRITE_ENTER(&softc->ipf_nat);
8247 
8248 	if (fin->fin_out == 0) {
8249 		nat = ipf_nat_outlookup(fin, nflags, (u_int)fin->fin_p,
8250 					fin->fin_dst, fin->fin_src);
8251 	} else {
8252 		nat = ipf_nat_inlookup(fin, nflags, (u_int)fin->fin_p,
8253 				       fin->fin_src, fin->fin_dst);
8254 	}
8255 
8256 	if (nat != NULL) {
8257 		NBUMPSIDE(fin->fin_out, ns_uncreate[0]);
8258 		ipf_nat_delete(softc, nat, NL_DESTROY);
8259 	} else {
8260 		NBUMPSIDE(fin->fin_out, ns_uncreate[1]);
8261 	}
8262 
8263 	RWLOCK_EXIT(&softc->ipf_nat);
8264 }
8265 
8266 
8267 /* ------------------------------------------------------------------------ */
8268 /* Function:    ipf_nat_cmp_rules                                           */
8269 /* Returns:     int   - 0 == success, else rules do not match.              */
8270 /* Parameters:  n1(I) - first rule to compare                               */
8271 /*              n2(I) - first rule to compare                               */
8272 /*                                                                          */
8273 /* Compare two rules using pointers to each rule. A straight bcmp will not  */
8274 /* work as some fields (such as in_dst, in_pkts) actually do change once    */
8275 /* the rule has been loaded into the kernel. Whilst this function returns   */
8276 /* various non-zero returns, they're strictly to aid in debugging. Use of   */
8277 /* this function should simply care if the result is zero or not.           */
8278 /* ------------------------------------------------------------------------ */
8279 static int
ipf_nat_cmp_rules(ipnat_t * n1,ipnat_t * n2)8280 ipf_nat_cmp_rules(ipnat_t *n1, ipnat_t *n2)
8281 {
8282 	if (n1->in_size != n2->in_size)
8283 		return 1;
8284 
8285 	if (bcmp((char *)&n1->in_v, (char *)&n2->in_v,
8286 		 offsetof(ipnat_t, in_ndst) - offsetof(ipnat_t, in_v)) != 0)
8287 		return 2;
8288 
8289 	if (bcmp((char *)&n1->in_tuc, (char *)&n2->in_tuc,
8290 		 n1->in_size - offsetof(ipnat_t, in_tuc)) != 0)
8291 		return 3;
8292 	if (n1->in_ndst.na_atype != n2->in_ndst.na_atype)
8293 		return 5;
8294 	if (n1->in_ndst.na_function != n2->in_ndst.na_function)
8295 		return 6;
8296 	if (bcmp((char *)&n1->in_ndst.na_addr, (char *)&n2->in_ndst.na_addr,
8297 		 sizeof(n1->in_ndst.na_addr)))
8298 		return 7;
8299 	if (n1->in_nsrc.na_atype != n2->in_nsrc.na_atype)
8300 		return 8;
8301 	if (n1->in_nsrc.na_function != n2->in_nsrc.na_function)
8302 		return 9;
8303 	if (bcmp((char *)&n1->in_nsrc.na_addr, (char *)&n2->in_nsrc.na_addr,
8304 		 sizeof(n1->in_nsrc.na_addr)))
8305 		return 10;
8306 	if (n1->in_odst.na_atype != n2->in_odst.na_atype)
8307 		return 11;
8308 	if (n1->in_odst.na_function != n2->in_odst.na_function)
8309 		return 12;
8310 	if (bcmp((char *)&n1->in_odst.na_addr, (char *)&n2->in_odst.na_addr,
8311 		 sizeof(n1->in_odst.na_addr)))
8312 		return 13;
8313 	if (n1->in_osrc.na_atype != n2->in_osrc.na_atype)
8314 		return 14;
8315 	if (n1->in_osrc.na_function != n2->in_osrc.na_function)
8316 		return 15;
8317 	if (bcmp((char *)&n1->in_osrc.na_addr, (char *)&n2->in_osrc.na_addr,
8318 		 sizeof(n1->in_osrc.na_addr)))
8319 		return 16;
8320 	return 0;
8321 }
8322 
8323 
8324 /* ------------------------------------------------------------------------ */
8325 /* Function:    ipf_nat_rule_init                                           */
8326 /* Returns:     int   - 0 == success, else rules do not match.              */
8327 /* Parameters:  softc(I) - pointer to soft context main structure           */
8328 /*              softn(I) - pointer to NAT context structure                 */
8329 /*              n(I)     - first rule to compare                            */
8330 /*                                                                          */
8331 /* ------------------------------------------------------------------------ */
8332 static int
ipf_nat_rule_init(ipf_main_softc_t * softc,ipf_nat_softc_t * softn,ipnat_t * n)8333 ipf_nat_rule_init(ipf_main_softc_t *softc, ipf_nat_softc_t *softn, ipnat_t *n)
8334 {
8335 	int error = 0;
8336 
8337 	if ((n->in_flags & IPN_SIPRANGE) != 0)
8338 		n->in_nsrcatype = FRI_RANGE;
8339 
8340 	if ((n->in_flags & IPN_DIPRANGE) != 0)
8341 		n->in_ndstatype = FRI_RANGE;
8342 
8343 	if ((n->in_flags & IPN_SPLIT) != 0)
8344 		n->in_ndstatype = FRI_SPLIT;
8345 
8346 	if ((n->in_redir & (NAT_MAP|NAT_REWRITE|NAT_DIVERTUDP)) != 0)
8347 		n->in_spnext = n->in_spmin;
8348 
8349 	if ((n->in_redir & (NAT_REWRITE|NAT_DIVERTUDP)) != 0) {
8350 		n->in_dpnext = n->in_dpmin;
8351 	} else if (n->in_redir == NAT_REDIRECT) {
8352 		n->in_dpnext = n->in_dpmin;
8353 	}
8354 
8355 	n->in_stepnext = 0;
8356 
8357 	switch (n->in_v[0])
8358 	{
8359 	case 4 :
8360 		error = ipf_nat_ruleaddrinit(softc, softn, n);
8361 		if (error != 0)
8362 			return error;
8363 		break;
8364 #ifdef USE_INET6
8365 	case 6 :
8366 		error = ipf_nat6_ruleaddrinit(softc, softn, n);
8367 		if (error != 0)
8368 			return error;
8369 		break;
8370 #endif
8371 	default :
8372 		break;
8373 	}
8374 
8375 	if (n->in_redir == (NAT_DIVERTUDP|NAT_MAP)) {
8376 		/*
8377 		 * Prerecord whether or not the destination of the divert
8378 		 * is local or not to the interface the packet is going
8379 		 * to be sent out.
8380 		 */
8381 		n->in_dlocal = ipf_deliverlocal(softc, n->in_v[1],
8382 						n->in_ifps[1], &n->in_ndstip6);
8383 	}
8384 
8385 	return error;
8386 }
8387 
8388 
8389 /* ------------------------------------------------------------------------ */
8390 /* Function:    ipf_nat_rule_fini                                           */
8391 /* Returns:     int   - 0 == success, else rules do not match.              */
8392 /* Parameters:  softc(I) - pointer to soft context main structure           */
8393 /*              n(I)     - rule to work on                                  */
8394 /*                                                                          */
8395 /* This function is used to release any objects that were referenced during */
8396 /* the rule initialisation. This is useful both when free'ing the rule and  */
8397 /* when handling ioctls that need to initialise these fields but not        */
8398 /* actually use them after the ioctl processing has finished.               */
8399 /* ------------------------------------------------------------------------ */
8400 static void
ipf_nat_rule_fini(ipf_main_softc_t * softc,ipnat_t * n)8401 ipf_nat_rule_fini(ipf_main_softc_t *softc, ipnat_t *n)
8402 {
8403 	if (n->in_odst.na_atype == FRI_LOOKUP && n->in_odst.na_ptr != NULL)
8404 		ipf_lookup_deref(softc, n->in_odst.na_type, n->in_odst.na_ptr);
8405 
8406 	if (n->in_osrc.na_atype == FRI_LOOKUP && n->in_osrc.na_ptr != NULL)
8407 		ipf_lookup_deref(softc, n->in_osrc.na_type, n->in_osrc.na_ptr);
8408 
8409 	if (n->in_ndst.na_atype == FRI_LOOKUP && n->in_ndst.na_ptr != NULL)
8410 		ipf_lookup_deref(softc, n->in_ndst.na_type, n->in_ndst.na_ptr);
8411 
8412 	if (n->in_nsrc.na_atype == FRI_LOOKUP && n->in_nsrc.na_ptr != NULL)
8413 		ipf_lookup_deref(softc, n->in_nsrc.na_type, n->in_nsrc.na_ptr);
8414 
8415 	if (n->in_divmp != NULL)
8416 		FREE_MB_T(n->in_divmp);
8417 }
8418