1 /* $FreeBSD: src/sys/netinet6/ip6_fw.c,v 1.2.2.10 2003/08/03 17:52:54 ume Exp $ */
2 /* $KAME: ip6_fw.c,v 1.21 2001/01/24 01:25:32 itojun Exp $ */
3
4 /*
5 * Copyright (C) 1998, 1999, 2000 and 2001 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * Copyright (c) 1993 Daniel Boulet
35 * Copyright (c) 1994 Ugen J.S.Antsilevich
36 * Copyright (c) 1996 Alex Nash
37 *
38 * Redistribution and use in source forms, with and without modification,
39 * are permitted provided that this entire comment appears intact.
40 *
41 * Redistribution in binary form may occur without any restrictions.
42 * Obviously, it would be nice if you gave credit where credit is due
43 * but requiring it would be too onerous.
44 *
45 * This software is provided ``AS IS'' without any warranties of any kind.
46 */
47
48 /*
49 * Implement IPv6 packet firewall
50 */
51
52 #if !defined(KLD_MODULE)
53 #include "opt_ip6fw.h"
54 #include "opt_inet.h"
55 #include "opt_inet6.h"
56 #endif
57
58 #ifdef IP6DIVERT
59 #error "NOT SUPPORTED IPV6 DIVERT"
60 #endif
61 #ifdef IP6FW_DIVERT_RESTART
62 #error "NOT SUPPORTED IPV6 DIVERT"
63 #endif
64
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/malloc.h>
68 #include <sys/mbuf.h>
69 #include <sys/queue.h>
70 #include <sys/kernel.h>
71 #include <sys/socket.h>
72 #include <sys/socketvar.h>
73 #include <sys/syslog.h>
74 #include <sys/thread2.h>
75 #include <sys/time.h>
76 #include <net/if.h>
77 #include <net/route.h>
78 #include <netinet/in_systm.h>
79 #include <netinet/in.h>
80 #include <netinet/ip.h>
81
82 #include <netinet/ip6.h>
83 #include <netinet6/ip6_var.h>
84 #include <netinet6/in6_var.h>
85 #include <netinet/icmp6.h>
86
87 #include <netinet/in_pcb.h>
88
89 #include "ip6_fw.h"
90 #include <netinet/ip_var.h>
91 #include <netinet/tcp.h>
92 #include <netinet/tcp_seq.h>
93 #include <netinet/tcp_timer.h>
94 #include <netinet/tcp_var.h>
95 #include <netinet/udp.h>
96
97 #include <sys/sysctl.h>
98
99 #include <net/net_osdep.h>
100
101 MALLOC_DEFINE(M_IP6FW, "Ip6Fw/Ip6Acct", "Ip6Fw/Ip6Acct chain's");
102
103 static int fw6_debug = 1;
104 #ifdef IPV6FIREWALL_VERBOSE
105 static int fw6_verbose = 1;
106 #else
107 static int fw6_verbose = 0;
108 #endif
109 #ifdef IPV6FIREWALL_VERBOSE_LIMIT
110 static int fw6_verbose_limit = IPV6FIREWALL_VERBOSE_LIMIT;
111 #else
112 static int fw6_verbose_limit = 0;
113 #endif
114
115 LIST_HEAD (ip6_fw_head, ip6_fw_chain) ip6_fw_chain;
116
117 #ifdef SYSCTL_NODE
118 SYSCTL_DECL(_net_inet6_ip6);
119 SYSCTL_NODE(_net_inet6_ip6, OID_AUTO, fw, CTLFLAG_RW, 0, "Firewall");
120 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, enable, CTLFLAG_RW,
121 &ip6_fw_enable, 0, "Enable ip6fw");
122 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, debug, CTLFLAG_RW, &fw6_debug, 0, "");
123 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, verbose, CTLFLAG_RW, &fw6_verbose, 0, "");
124 SYSCTL_INT(_net_inet6_ip6_fw, OID_AUTO, verbose_limit, CTLFLAG_RW, &fw6_verbose_limit, 0, "");
125 #endif
126
127 #define dprintf(a) do { \
128 if (fw6_debug) \
129 kprintf a; \
130 } while (0)
131 #define SNPARGS(buf, len) buf + len, sizeof(buf) > len ? sizeof(buf) - len : 0
132
133 static int add_entry6 (struct ip6_fw_head *chainptr, struct ip6_fw *frwl);
134 static int del_entry6 (struct ip6_fw_head *chainptr, u_short number);
135 static int zero_entry6 (struct mbuf *m);
136 static struct ip6_fw *check_ip6fw_struct (struct ip6_fw *m);
137 static struct ip6_fw *check_ip6fw_mbuf (struct mbuf *fw);
138 static int ip6opts_match (struct ip6_hdr **ip6, struct ip6_fw *f,
139 struct mbuf **m,
140 int *off, int *nxt, u_short *offset);
141 static int port_match6 (u_short *portptr, int nports, u_short port,
142 int range_flag);
143 static int tcp6flg_match (struct tcphdr *tcp6, struct ip6_fw *f);
144 static int icmp6type_match (struct icmp6_hdr * icmp, struct ip6_fw * f);
145 static void ip6fw_report (struct ip6_fw *f, struct ip6_hdr *ip6,
146 struct ifnet *rif, struct ifnet *oif, int off, int nxt);
147
148 static int ip6_fw_chk (struct ip6_hdr **pip6,
149 struct ifnet *oif, u_int16_t *cookie, struct mbuf **m);
150 static int ip6_fw_ctl (int stage, struct mbuf **mm);
151
152 static char err_prefix[] = "ip6_fw_ctl:";
153
154 /*
155 * Returns 1 if the port is matched by the vector, 0 otherwise
156 */
157 static __inline int
port_match6(u_short * portptr,int nports,u_short port,int range_flag)158 port_match6(u_short *portptr, int nports, u_short port, int range_flag)
159 {
160 if (!nports)
161 return 1;
162 if (range_flag) {
163 if (portptr[0] <= port && port <= portptr[1]) {
164 return 1;
165 }
166 nports -= 2;
167 portptr += 2;
168 }
169 while (nports-- > 0) {
170 if (*portptr++ == port) {
171 return 1;
172 }
173 }
174 return 0;
175 }
176
177 static int
tcp6flg_match(struct tcphdr * tcp6,struct ip6_fw * f)178 tcp6flg_match(struct tcphdr *tcp6, struct ip6_fw *f)
179 {
180 u_char flg_set, flg_clr;
181
182 /*
183 * If an established connection is required, reject packets that
184 * have only SYN of RST|ACK|SYN set. Otherwise, fall through to
185 * other flag requirements.
186 */
187 if ((f->fw_ipflg & IPV6_FW_IF_TCPEST) &&
188 ((tcp6->th_flags & (IPV6_FW_TCPF_RST | IPV6_FW_TCPF_ACK |
189 IPV6_FW_TCPF_SYN)) == IPV6_FW_TCPF_SYN))
190 return 0;
191
192 flg_set = tcp6->th_flags & f->fw_tcpf;
193 flg_clr = tcp6->th_flags & f->fw_tcpnf;
194
195 if (flg_set != f->fw_tcpf)
196 return 0;
197 if (flg_clr)
198 return 0;
199
200 return 1;
201 }
202
203 static int
icmp6type_match(struct icmp6_hdr * icmp6,struct ip6_fw * f)204 icmp6type_match(struct icmp6_hdr *icmp6, struct ip6_fw *f)
205 {
206 int type;
207
208 if (!(f->fw_flg & IPV6_FW_F_ICMPBIT))
209 return(1);
210
211 type = icmp6->icmp6_type;
212
213 /* check for matching type in the bitmap */
214 if (type < IPV6_FW_ICMPTYPES_DIM * sizeof(unsigned) * 8 &&
215 (f->fw_icmp6types[type / (sizeof(unsigned) * 8)] &
216 (1U << (type % (8 * sizeof(unsigned))))))
217 return(1);
218
219 return(0); /* no match */
220 }
221
222 static int
is_icmp6_query(struct ip6_hdr * ip6,int off)223 is_icmp6_query(struct ip6_hdr *ip6, int off)
224 {
225 const struct icmp6_hdr *icmp6;
226 int icmp6_type;
227
228 icmp6 = (struct icmp6_hdr *)((caddr_t)ip6 + off);
229 icmp6_type = icmp6->icmp6_type;
230
231 if (icmp6_type == ICMP6_ECHO_REQUEST ||
232 icmp6_type == ICMP6_MEMBERSHIP_QUERY ||
233 icmp6_type == ICMP6_WRUREQUEST ||
234 icmp6_type == ICMP6_FQDN_QUERY ||
235 icmp6_type == ICMP6_NI_QUERY)
236 return(1);
237
238 return(0);
239 }
240
241 static int
ip6opts_match(struct ip6_hdr ** pip6,struct ip6_fw * f,struct mbuf ** m,int * off,int * nxt,u_short * offset)242 ip6opts_match(struct ip6_hdr **pip6, struct ip6_fw *f, struct mbuf **m,
243 int *off, int *nxt, u_short *offset)
244 {
245 int len;
246 struct ip6_hdr *ip6 = *pip6;
247 struct ip6_ext *ip6e;
248 u_char opts, nopts, nopts_sve;
249
250 opts = f->fw_ip6opt;
251 nopts = nopts_sve = f->fw_ip6nopt;
252
253 *nxt = ip6->ip6_nxt;
254 *off = sizeof(struct ip6_hdr);
255 len = ntohs(ip6->ip6_plen) + sizeof(struct ip6_hdr);
256 while (*off < len) {
257 ip6e = (struct ip6_ext *)((caddr_t) ip6 + *off);
258 if ((*m)->m_len < *off + sizeof(*ip6e))
259 goto opts_check; /* XXX */
260
261 switch (*nxt) {
262 case IPPROTO_FRAGMENT:
263 if ((*m)->m_len >= *off + sizeof(struct ip6_frag)) {
264 struct ip6_frag *ip6f;
265
266 ip6f = (struct ip6_frag *) ((caddr_t)ip6 + *off);
267 *offset = ip6f->ip6f_offlg & IP6F_OFF_MASK;
268 }
269 opts &= ~IPV6_FW_IP6OPT_FRAG;
270 nopts &= ~IPV6_FW_IP6OPT_FRAG;
271 *off += sizeof(struct ip6_frag);
272 break;
273 case IPPROTO_AH:
274 opts &= ~IPV6_FW_IP6OPT_AH;
275 nopts &= ~IPV6_FW_IP6OPT_AH;
276 *off += (ip6e->ip6e_len + 2) << 2;
277 break;
278 default:
279 switch (*nxt) {
280 case IPPROTO_HOPOPTS:
281 opts &= ~IPV6_FW_IP6OPT_HOPOPT;
282 nopts &= ~IPV6_FW_IP6OPT_HOPOPT;
283 break;
284 case IPPROTO_ROUTING:
285 opts &= ~IPV6_FW_IP6OPT_ROUTE;
286 nopts &= ~IPV6_FW_IP6OPT_ROUTE;
287 break;
288 case IPPROTO_ESP:
289 opts &= ~IPV6_FW_IP6OPT_ESP;
290 nopts &= ~IPV6_FW_IP6OPT_ESP;
291 goto opts_check;
292 case IPPROTO_NONE:
293 opts &= ~IPV6_FW_IP6OPT_NONXT;
294 nopts &= ~IPV6_FW_IP6OPT_NONXT;
295 goto opts_check;
296 case IPPROTO_DSTOPTS:
297 opts &= ~IPV6_FW_IP6OPT_OPTS;
298 nopts &= ~IPV6_FW_IP6OPT_OPTS;
299 break;
300 default:
301 goto opts_check;
302 }
303 *off += (ip6e->ip6e_len + 1) << 3;
304 break;
305 }
306 *nxt = ip6e->ip6e_nxt;
307
308 }
309 opts_check:
310 if (f->fw_ip6opt == f->fw_ip6nopt) /* XXX */
311 return 1;
312
313 if (opts == 0 && nopts == nopts_sve)
314 return 1;
315 else
316 return 0;
317 }
318
319 static __inline int
iface_match(struct ifnet * ifp,union ip6_fw_if * ifu,int byname)320 iface_match(struct ifnet *ifp, union ip6_fw_if *ifu, int byname)
321 {
322 /* Check by name or by IP address */
323 if (byname) {
324 /* Check name */
325 if (ifu->fu_via_if.glob) {
326 if (kfnmatch(ifu->fu_via_if.name, ifp->if_xname, 0)
327 == FNM_NOMATCH)
328 return(0);
329 } else {
330 if (strncmp(ifp->if_xname, ifu->fu_via_if.name,
331 IP6FW_IFNLEN) != 0)
332 return(0);
333 }
334 return(1);
335 } else if (!IN6_IS_ADDR_UNSPECIFIED(&ifu->fu_via_ip6)) { /* Zero == wildcard */
336 struct ifaddr_container *ifac;
337
338 TAILQ_FOREACH(ifac, &ifp->if_addrheads[mycpuid], ifa_link) {
339 struct ifaddr *ifa = ifac->ifa;
340
341 if (ifa->ifa_addr == NULL)
342 continue;
343 if (ifa->ifa_addr->sa_family != AF_INET6)
344 continue;
345 if (!IN6_ARE_ADDR_EQUAL(&ifu->fu_via_ip6,
346 &(((struct sockaddr_in6 *)
347 (ifa->ifa_addr))->sin6_addr)))
348 continue;
349 return(1);
350 }
351 return(0);
352 }
353 return(1);
354 }
355
356 static void
ip6fw_report(struct ip6_fw * f,struct ip6_hdr * ip6,struct ifnet * rif,struct ifnet * oif,int off,int nxt)357 ip6fw_report(struct ip6_fw *f, struct ip6_hdr *ip6,
358 struct ifnet *rif, struct ifnet *oif, int off, int nxt)
359 {
360 static int counter;
361 struct tcphdr *const tcp6 = (struct tcphdr *) ((caddr_t) ip6+ off);
362 struct udphdr *const udp = (struct udphdr *) ((caddr_t) ip6+ off);
363 struct icmp6_hdr *const icmp6 = (struct icmp6_hdr *) ((caddr_t) ip6+ off);
364 int count;
365 char *action;
366 char action2[32], proto[102], name[18];
367 int len;
368
369 count = f ? f->fw_pcnt : ++counter;
370 if (fw6_verbose_limit != 0 && count > fw6_verbose_limit)
371 return;
372
373 /* Print command name */
374 ksnprintf(SNPARGS(name, 0), "ip6fw: %d", f ? f->fw_number : -1);
375
376 action = action2;
377 if (!f)
378 action = "Refuse";
379 else {
380 switch (f->fw_flg & IPV6_FW_F_COMMAND) {
381 case IPV6_FW_F_DENY:
382 action = "Deny";
383 break;
384 case IPV6_FW_F_REJECT:
385 if (f->fw_reject_code == IPV6_FW_REJECT_RST)
386 action = "Reset";
387 else
388 action = "Unreach";
389 break;
390 case IPV6_FW_F_ACCEPT:
391 action = "Accept";
392 break;
393 case IPV6_FW_F_COUNT:
394 action = "Count";
395 break;
396 case IPV6_FW_F_DIVERT:
397 ksnprintf(SNPARGS(action2, 0), "Divert %d",
398 f->fw_divert_port);
399 break;
400 case IPV6_FW_F_TEE:
401 ksnprintf(SNPARGS(action2, 0), "Tee %d",
402 f->fw_divert_port);
403 break;
404 case IPV6_FW_F_SKIPTO:
405 ksnprintf(SNPARGS(action2, 0), "SkipTo %d",
406 f->fw_skipto_rule);
407 break;
408 default:
409 action = "UNKNOWN";
410 break;
411 }
412 }
413
414 switch (nxt) {
415 case IPPROTO_TCP:
416 len = ksnprintf(SNPARGS(proto, 0), "TCP [%s]",
417 ip6_sprintf(&ip6->ip6_src));
418 if (off > 0)
419 len += ksnprintf(SNPARGS(proto, len), ":%d ",
420 ntohs(tcp6->th_sport));
421 else
422 len += ksnprintf(SNPARGS(proto, len), " ");
423 len += ksnprintf(SNPARGS(proto, len), "[%s]",
424 ip6_sprintf(&ip6->ip6_dst));
425 if (off > 0)
426 ksnprintf(SNPARGS(proto, len), ":%d",
427 ntohs(tcp6->th_dport));
428 break;
429 case IPPROTO_UDP:
430 len = ksnprintf(SNPARGS(proto, 0), "UDP [%s]",
431 ip6_sprintf(&ip6->ip6_src));
432 if (off > 0)
433 len += ksnprintf(SNPARGS(proto, len), ":%d ",
434 ntohs(udp->uh_sport));
435 else
436 len += ksnprintf(SNPARGS(proto, len), " ");
437 len += ksnprintf(SNPARGS(proto, len), "[%s]",
438 ip6_sprintf(&ip6->ip6_dst));
439 if (off > 0)
440 ksnprintf(SNPARGS(proto, len), ":%d",
441 ntohs(udp->uh_dport));
442 break;
443 case IPPROTO_ICMPV6:
444 if (off > 0)
445 len = ksnprintf(SNPARGS(proto, 0), "IPV6-ICMP:%u.%u ",
446 icmp6->icmp6_type, icmp6->icmp6_code);
447 else
448 len = ksnprintf(SNPARGS(proto, 0), "IPV6-ICMP ");
449 len += ksnprintf(SNPARGS(proto, len), "[%s]",
450 ip6_sprintf(&ip6->ip6_src));
451 ksnprintf(SNPARGS(proto, len), " [%s]",
452 ip6_sprintf(&ip6->ip6_dst));
453 break;
454 default:
455 len = ksnprintf(SNPARGS(proto, 0), "P:%d [%s]", nxt,
456 ip6_sprintf(&ip6->ip6_src));
457 ksnprintf(SNPARGS(proto, len), " [%s]",
458 ip6_sprintf(&ip6->ip6_dst));
459 break;
460 }
461
462 if (oif)
463 log(LOG_SECURITY | LOG_INFO, "%s %s %s out via %s\n",
464 name, action, proto, if_name(oif));
465 else if (rif)
466 log(LOG_SECURITY | LOG_INFO, "%s %s %s in via %s\n",
467 name, action, proto, if_name(rif));
468 else
469 log(LOG_SECURITY | LOG_INFO, "%s %s %s",
470 name, action, proto);
471 if (fw6_verbose_limit != 0 && count == fw6_verbose_limit)
472 log(LOG_SECURITY | LOG_INFO, "ip6fw: limit reached on entry %d\n",
473 f ? f->fw_number : -1);
474 }
475
476 /*
477 * Parameters:
478 *
479 * ip Pointer to packet header (struct ip6_hdr *)
480 * hlen Packet header length
481 * oif Outgoing interface, or NULL if packet is incoming
482 * #ifndef IP6FW_DIVERT_RESTART
483 * *cookie Ignore all divert/tee rules to this port (if non-zero)
484 * #else
485 * *cookie Skip up to the first rule past this rule number;
486 * #endif
487 * *m The packet; we set to NULL when/if we nuke it.
488 *
489 * Return value:
490 *
491 * 0 The packet is to be accepted and routed normally OR
492 * the packet was denied/rejected and has been dropped;
493 * in the latter case, *m is equal to NULL upon return.
494 * port Divert the packet to port.
495 */
496
497 static int
ip6_fw_chk(struct ip6_hdr ** pip6,struct ifnet * oif,u_int16_t * cookie,struct mbuf ** m)498 ip6_fw_chk(struct ip6_hdr **pip6,
499 struct ifnet *oif, u_int16_t *cookie, struct mbuf **m)
500 {
501 struct ip6_fw_chain *chain;
502 struct ip6_fw *rule = NULL;
503 struct ip6_hdr *ip6 = *pip6;
504 struct ifnet *const rif = (*m)->m_pkthdr.rcvif;
505 u_short offset = 0;
506 int off = sizeof(struct ip6_hdr), nxt = ip6->ip6_nxt;
507 u_short src_port, dst_port;
508 #ifdef IP6FW_DIVERT_RESTART
509 u_int16_t skipto = *cookie;
510 #else
511 u_int16_t ignport = ntohs(*cookie);
512 #endif
513
514 *cookie = 0;
515 /*
516 * Go down the chain, looking for enlightment
517 * #ifdef IP6FW_DIVERT_RESTART
518 * If we've been asked to start at a given rule immediatly, do so.
519 * #endif
520 */
521 chain = LIST_FIRST(&ip6_fw_chain);
522 #ifdef IP6FW_DIVERT_RESTART
523 if (skipto) {
524 if (skipto >= 65535)
525 goto dropit;
526 while (chain && (chain->rule->fw_number <= skipto)) {
527 chain = LIST_NEXT(chain, chain);
528 }
529 if (! chain) goto dropit;
530 }
531 #endif /* IP6FW_DIVERT_RESTART */
532 for (; chain; chain = LIST_NEXT(chain, chain)) {
533 struct ip6_fw *const f = chain->rule;
534
535 if (oif) {
536 /* Check direction outbound */
537 if (!(f->fw_flg & IPV6_FW_F_OUT))
538 continue;
539 } else {
540 /* Check direction inbound */
541 if (!(f->fw_flg & IPV6_FW_F_IN))
542 continue;
543 }
544
545 #define IN6_ARE_ADDR_MASKEQUAL(x,y,z) (\
546 (((x)->s6_addr32[0] & (y)->s6_addr32[0]) == (z)->s6_addr32[0]) && \
547 (((x)->s6_addr32[1] & (y)->s6_addr32[1]) == (z)->s6_addr32[1]) && \
548 (((x)->s6_addr32[2] & (y)->s6_addr32[2]) == (z)->s6_addr32[2]) && \
549 (((x)->s6_addr32[3] & (y)->s6_addr32[3]) == (z)->s6_addr32[3]))
550
551 /* If src-addr doesn't match, not this rule. */
552 if (((f->fw_flg & IPV6_FW_F_INVSRC) != 0) ^
553 (!IN6_ARE_ADDR_MASKEQUAL(&ip6->ip6_src,&f->fw_smsk,&f->fw_src)))
554 continue;
555
556 /* If dest-addr doesn't match, not this rule. */
557 if (((f->fw_flg & IPV6_FW_F_INVDST) != 0) ^
558 (!IN6_ARE_ADDR_MASKEQUAL(&ip6->ip6_dst,&f->fw_dmsk,&f->fw_dst)))
559 continue;
560
561 #undef IN6_ARE_ADDR_MASKEQUAL
562 /* Interface check */
563 if ((f->fw_flg & IF6_FW_F_VIAHACK) == IF6_FW_F_VIAHACK) {
564 struct ifnet *const iface = oif ? oif : rif;
565
566 /* Backwards compatibility hack for "via" */
567 if (!iface || !iface_match(iface,
568 &f->fw_in_if, f->fw_flg & IPV6_FW_F_OIFNAME))
569 continue;
570 } else {
571 /* Check receive interface */
572 if ((f->fw_flg & IPV6_FW_F_IIFACE)
573 && (!rif || !iface_match(rif,
574 &f->fw_in_if, f->fw_flg & IPV6_FW_F_IIFNAME)))
575 continue;
576 /* Check outgoing interface */
577 if ((f->fw_flg & IPV6_FW_F_OIFACE)
578 && (!oif || !iface_match(oif,
579 &f->fw_out_if, f->fw_flg & IPV6_FW_F_OIFNAME)))
580 continue;
581 }
582
583 /* Check IP options */
584 if (!ip6opts_match(&ip6, f, m, &off, &nxt, &offset))
585 continue;
586
587 /* Fragments */
588 if ((f->fw_flg & IPV6_FW_F_FRAG) && !offset)
589 continue;
590
591 /* Check protocol; if wildcard, match */
592 if (f->fw_prot == IPPROTO_IPV6)
593 goto got_match;
594
595 /* If different, don't match */
596 if (nxt != f->fw_prot)
597 continue;
598
599 #define PULLUP_TO(len) do { \
600 if ((*m)->m_len < (len) \
601 && (*m = m_pullup(*m, (len))) == NULL) {\
602 goto dropit; \
603 } \
604 *pip6 = ip6 = mtod(*m, struct ip6_hdr *); \
605 } while (0)
606
607 /* Protocol specific checks */
608 switch (nxt) {
609 case IPPROTO_TCP:
610 {
611 struct tcphdr *tcp6;
612
613 if (offset == 1) { /* cf. RFC 1858 */
614 PULLUP_TO(off + 4); /* XXX ? */
615 goto bogusfrag;
616 }
617 if (offset != 0) {
618 /*
619 * TCP flags and ports aren't available in this
620 * packet -- if this rule specified either one,
621 * we consider the rule a non-match.
622 */
623 if (f->fw_nports != 0 ||
624 f->fw_tcpf != f->fw_tcpnf)
625 continue;
626
627 break;
628 }
629 PULLUP_TO(off + 14);
630 tcp6 = (struct tcphdr *) ((caddr_t)ip6 + off);
631 if (((f->fw_tcpf != f->fw_tcpnf) ||
632 (f->fw_ipflg & IPV6_FW_IF_TCPEST)) &&
633 !tcp6flg_match(tcp6, f))
634 continue;
635 src_port = ntohs(tcp6->th_sport);
636 dst_port = ntohs(tcp6->th_dport);
637 goto check_ports;
638 }
639
640 case IPPROTO_UDP:
641 {
642 struct udphdr *udp;
643
644 if (offset != 0) {
645 /*
646 * Port specification is unavailable -- if this
647 * rule specifies a port, we consider the rule
648 * a non-match.
649 */
650 if (f->fw_nports != 0)
651 continue;
652
653 break;
654 }
655 PULLUP_TO(off + 4);
656 udp = (struct udphdr *) ((caddr_t)ip6 + off);
657 src_port = ntohs(udp->uh_sport);
658 dst_port = ntohs(udp->uh_dport);
659 check_ports:
660 if (!port_match6(&f->fw_pts[0],
661 IPV6_FW_GETNSRCP(f), src_port,
662 f->fw_flg & IPV6_FW_F_SRNG))
663 continue;
664 if (!port_match6(&f->fw_pts[IPV6_FW_GETNSRCP(f)],
665 IPV6_FW_GETNDSTP(f), dst_port,
666 f->fw_flg & IPV6_FW_F_DRNG))
667 continue;
668 break;
669 }
670
671 case IPPROTO_ICMPV6:
672 {
673 struct icmp6_hdr *icmp;
674
675 if (offset != 0) /* Type isn't valid */
676 break;
677 PULLUP_TO(off + 2);
678 icmp = (struct icmp6_hdr *) ((caddr_t)ip6 + off);
679 if (!icmp6type_match(icmp, f))
680 continue;
681 break;
682 }
683 #undef PULLUP_TO
684
685 bogusfrag:
686 if (fw6_verbose)
687 ip6fw_report(NULL, ip6, rif, oif, off, nxt);
688 goto dropit;
689 }
690
691 got_match:
692 #ifndef IP6FW_DIVERT_RESTART
693 /* Ignore divert/tee rule if socket port is "ignport" */
694 switch (f->fw_flg & IPV6_FW_F_COMMAND) {
695 case IPV6_FW_F_DIVERT:
696 case IPV6_FW_F_TEE:
697 if (f->fw_divert_port == ignport)
698 continue; /* ignore this rule */
699 break;
700 }
701
702 #endif /* IP6FW_DIVERT_RESTART */
703 /* Update statistics */
704 f->fw_pcnt += 1;
705 f->fw_bcnt += ntohs(ip6->ip6_plen);
706 f->timestamp = time_second;
707
708 /* Log to console if desired */
709 if ((f->fw_flg & IPV6_FW_F_PRN) && fw6_verbose)
710 ip6fw_report(f, ip6, rif, oif, off, nxt);
711
712 /* Take appropriate action */
713 switch (f->fw_flg & IPV6_FW_F_COMMAND) {
714 case IPV6_FW_F_ACCEPT:
715 return(0);
716 case IPV6_FW_F_COUNT:
717 continue;
718 case IPV6_FW_F_DIVERT:
719 #ifdef IP6FW_DIVERT_RESTART
720 *cookie = f->fw_number;
721 #else
722 *cookie = htons(f->fw_divert_port);
723 #endif /* IP6FW_DIVERT_RESTART */
724 return(f->fw_divert_port);
725 case IPV6_FW_F_TEE:
726 /*
727 * XXX someday tee packet here, but beware that you
728 * can't use m_copym() or m_copypacket() because
729 * the divert input routine modifies the mbuf
730 * (and these routines only increment reference
731 * counts in the case of mbuf clusters), so need
732 * to write custom routine.
733 */
734 continue;
735 case IPV6_FW_F_SKIPTO:
736 #ifdef DIAGNOSTIC
737 while (chain->chain.le_next
738 && chain->chain.le_next->rule->fw_number
739 < f->fw_skipto_rule)
740 #else
741 while (chain->chain.le_next->rule->fw_number
742 < f->fw_skipto_rule)
743 #endif
744 chain = chain->chain.le_next;
745 continue;
746 }
747
748 /* Deny/reject this packet using this rule */
749 rule = f;
750 break;
751 }
752
753 #ifdef DIAGNOSTIC
754 /* Rule 65535 should always be there and should always match */
755 if (!chain)
756 panic("ip6_fw: chain");
757 #endif
758
759 /*
760 * At this point, we're going to drop the packet.
761 * Send a reject notice if all of the following are true:
762 *
763 * - The packet matched a reject rule
764 * - The packet is not an ICMP packet, or is an ICMP query packet
765 * - The packet is not a multicast or broadcast packet
766 */
767 if ((rule->fw_flg & IPV6_FW_F_COMMAND) == IPV6_FW_F_REJECT
768 && (nxt != IPPROTO_ICMPV6 || is_icmp6_query(ip6, off))
769 && !((*m)->m_flags & (M_BCAST|M_MCAST))
770 && !IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
771 switch (rule->fw_reject_code) {
772 case IPV6_FW_REJECT_RST:
773 #if 1 /* not tested */
774 {
775 struct tcphdr *const tcp =
776 (struct tcphdr *) ((caddr_t)ip6 + off);
777 struct {
778 struct ip6_hdr ip6;
779 struct tcphdr th;
780 } ti;
781 tcp_seq ack, seq;
782 int flags;
783
784 if (offset != 0 || (tcp->th_flags & TH_RST))
785 break;
786
787 ti.ip6 = *ip6;
788 ti.th = *tcp;
789 ti.th.th_seq = ntohl(ti.th.th_seq);
790 ti.th.th_ack = ntohl(ti.th.th_ack);
791 ti.ip6.ip6_nxt = IPPROTO_TCP;
792 if (ti.th.th_flags & TH_ACK) {
793 ack = 0;
794 seq = ti.th.th_ack;
795 flags = TH_RST;
796 } else {
797 ack = ti.th.th_seq;
798 if (((*m)->m_flags & M_PKTHDR) != 0) {
799 ack += (*m)->m_pkthdr.len - off
800 - (ti.th.th_off << 2);
801 } else if (ip6->ip6_plen) {
802 ack += ntohs(ip6->ip6_plen) + sizeof(*ip6)
803 - off - (ti.th.th_off << 2);
804 } else {
805 m_freem(*m);
806 *m = NULL;
807 break;
808 }
809 seq = 0;
810 flags = TH_RST|TH_ACK;
811 }
812 bcopy(&ti, ip6, sizeof(ti));
813 tcp_respond(NULL, ip6, (struct tcphdr *)(ip6 + 1),
814 *m, ack, seq, flags);
815 *m = NULL;
816 break;
817 }
818 #endif
819 default: /* Send an ICMP unreachable using code */
820 if (oif)
821 (*m)->m_pkthdr.rcvif = oif;
822 icmp6_error(*m, ICMP6_DST_UNREACH,
823 rule->fw_reject_code, 0);
824 *m = NULL;
825 break;
826 }
827 }
828
829 dropit:
830 /*
831 * Finally, drop the packet.
832 */
833 if (*m) {
834 m_freem(*m);
835 *m = NULL;
836 }
837 return(0);
838 }
839
840 static int
add_entry6(struct ip6_fw_head * chainptr,struct ip6_fw * frwl)841 add_entry6(struct ip6_fw_head *chainptr, struct ip6_fw *frwl)
842 {
843 struct ip6_fw *ftmp = NULL;
844 struct ip6_fw_chain *fwc = NULL, *fcp, *fcpl = NULL;
845 u_short nbr = 0;
846
847 fwc = kmalloc(sizeof *fwc, M_IP6FW, M_INTWAIT);
848 ftmp = kmalloc(sizeof *ftmp, M_IP6FW, M_INTWAIT);
849
850 bcopy(frwl, ftmp, sizeof(struct ip6_fw));
851 ftmp->fw_in_if.fu_via_if.name[IP6FW_IFNLEN - 1] = '\0';
852 ftmp->fw_pcnt = 0L;
853 ftmp->fw_bcnt = 0L;
854 fwc->rule = ftmp;
855
856 crit_enter();
857
858 if (!chainptr->lh_first) {
859 LIST_INSERT_HEAD(chainptr, fwc, chain);
860 crit_exit();
861 return(0);
862 } else if (ftmp->fw_number == (u_short)-1) {
863 if (fwc) kfree(fwc, M_IP6FW);
864 if (ftmp) kfree(ftmp, M_IP6FW);
865 crit_exit();
866 dprintf(("%s bad rule number\n", err_prefix));
867 return (EINVAL);
868 }
869
870 /* If entry number is 0, find highest numbered rule and add 100 */
871 if (ftmp->fw_number == 0) {
872 LIST_FOREACH(fcp, chainptr, chain) {
873 if (fcp->rule->fw_number != (u_short)-1)
874 nbr = fcp->rule->fw_number;
875 else
876 break;
877 }
878 if (nbr < (u_short)-1 - 100)
879 nbr += 100;
880 ftmp->fw_number = nbr;
881 }
882
883 /* Got a valid number; now insert it, keeping the list ordered */
884 LIST_FOREACH(fcp, chainptr, chain) {
885 if (fcp->rule->fw_number > ftmp->fw_number) {
886 if (fcpl) {
887 LIST_INSERT_AFTER(fcpl, fwc, chain);
888 } else {
889 LIST_INSERT_HEAD(chainptr, fwc, chain);
890 }
891 break;
892 } else {
893 fcpl = fcp;
894 }
895 }
896
897 crit_exit();
898 return (0);
899 }
900
901 static int
del_entry6(struct ip6_fw_head * chainptr,u_short number)902 del_entry6(struct ip6_fw_head *chainptr, u_short number)
903 {
904 struct ip6_fw_chain *fcp;
905
906 crit_enter();
907
908 fcp = chainptr->lh_first;
909 if (number != (u_short)-1) {
910 for (; fcp; fcp = fcp->chain.le_next) {
911 if (fcp->rule->fw_number == number) {
912 LIST_REMOVE(fcp, chain);
913 crit_exit();
914 kfree(fcp->rule, M_IP6FW);
915 kfree(fcp, M_IP6FW);
916 return 0;
917 }
918 }
919 }
920
921 crit_exit();
922 return (EINVAL);
923 }
924
925 static int
zero_entry6(struct mbuf * m)926 zero_entry6(struct mbuf *m)
927 {
928 struct ip6_fw *frwl;
929 struct ip6_fw_chain *fcp;
930
931 if (m && m->m_len != 0) {
932 if (m->m_len != sizeof(struct ip6_fw))
933 return(EINVAL);
934 frwl = mtod(m, struct ip6_fw *);
935 }
936 else
937 frwl = NULL;
938
939 /*
940 * It's possible to insert multiple chain entries with the
941 * same number, so we don't stop after finding the first
942 * match if zeroing a specific entry.
943 */
944 crit_enter();
945 for (fcp = ip6_fw_chain.lh_first; fcp; fcp = fcp->chain.le_next)
946 if (!frwl || frwl->fw_number == fcp->rule->fw_number) {
947 fcp->rule->fw_bcnt = fcp->rule->fw_pcnt = 0;
948 fcp->rule->timestamp = 0;
949 }
950 crit_exit();
951
952 if (fw6_verbose) {
953 if (frwl)
954 log(LOG_SECURITY | LOG_NOTICE,
955 "ip6fw: Entry %d cleared.\n", frwl->fw_number);
956 else
957 log(LOG_SECURITY | LOG_NOTICE,
958 "ip6fw: Accounting cleared.\n");
959 }
960
961 return(0);
962 }
963
964 static struct ip6_fw *
check_ip6fw_mbuf(struct mbuf * m)965 check_ip6fw_mbuf(struct mbuf *m)
966 {
967 /* Check length */
968 if (m->m_len != sizeof(struct ip6_fw)) {
969 dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len,
970 (int)sizeof(struct ip6_fw)));
971 return (NULL);
972 }
973 return(check_ip6fw_struct(mtod(m, struct ip6_fw *)));
974 }
975
976 static struct ip6_fw *
check_ip6fw_struct(struct ip6_fw * frwl)977 check_ip6fw_struct(struct ip6_fw *frwl)
978 {
979 /* Check for invalid flag bits */
980 if ((frwl->fw_flg & ~IPV6_FW_F_MASK) != 0) {
981 dprintf(("%s undefined flag bits set (flags=%x)\n",
982 err_prefix, frwl->fw_flg));
983 return (NULL);
984 }
985 /* Must apply to incoming or outgoing (or both) */
986 if (!(frwl->fw_flg & (IPV6_FW_F_IN | IPV6_FW_F_OUT))) {
987 dprintf(("%s neither in nor out\n", err_prefix));
988 return (NULL);
989 }
990 /* Empty interface name is no good */
991 if (((frwl->fw_flg & IPV6_FW_F_IIFNAME)
992 && !*frwl->fw_in_if.fu_via_if.name)
993 || ((frwl->fw_flg & IPV6_FW_F_OIFNAME)
994 && !*frwl->fw_out_if.fu_via_if.name)) {
995 dprintf(("%s empty interface name\n", err_prefix));
996 return (NULL);
997 }
998 /* Sanity check interface matching */
999 if ((frwl->fw_flg & IF6_FW_F_VIAHACK) == IF6_FW_F_VIAHACK) {
1000 ; /* allow "via" backwards compatibility */
1001 } else if ((frwl->fw_flg & IPV6_FW_F_IN)
1002 && (frwl->fw_flg & IPV6_FW_F_OIFACE)) {
1003 dprintf(("%s outgoing interface check on incoming\n",
1004 err_prefix));
1005 return (NULL);
1006 }
1007 /* Sanity check port ranges */
1008 if ((frwl->fw_flg & IPV6_FW_F_SRNG) && IPV6_FW_GETNSRCP(frwl) < 2) {
1009 dprintf(("%s src range set but n_src_p=%d\n",
1010 err_prefix, IPV6_FW_GETNSRCP(frwl)));
1011 return (NULL);
1012 }
1013 if ((frwl->fw_flg & IPV6_FW_F_DRNG) && IPV6_FW_GETNDSTP(frwl) < 2) {
1014 dprintf(("%s dst range set but n_dst_p=%d\n",
1015 err_prefix, IPV6_FW_GETNDSTP(frwl)));
1016 return (NULL);
1017 }
1018 if (IPV6_FW_GETNSRCP(frwl) + IPV6_FW_GETNDSTP(frwl) > IPV6_FW_MAX_PORTS) {
1019 dprintf(("%s too many ports (%d+%d)\n",
1020 err_prefix, IPV6_FW_GETNSRCP(frwl), IPV6_FW_GETNDSTP(frwl)));
1021 return (NULL);
1022 }
1023 /*
1024 * Protocols other than TCP/UDP don't use port range
1025 */
1026 if ((frwl->fw_prot != IPPROTO_TCP) &&
1027 (frwl->fw_prot != IPPROTO_UDP) &&
1028 (IPV6_FW_GETNSRCP(frwl) || IPV6_FW_GETNDSTP(frwl))) {
1029 dprintf(("%s port(s) specified for non TCP/UDP rule\n",
1030 err_prefix));
1031 return(NULL);
1032 }
1033
1034 /*
1035 * Rather than modify the entry to make such entries work,
1036 * we reject this rule and require user level utilities
1037 * to enforce whatever policy they deem appropriate.
1038 */
1039 if ((frwl->fw_src.s6_addr32[0] & (~frwl->fw_smsk.s6_addr32[0])) ||
1040 (frwl->fw_src.s6_addr32[1] & (~frwl->fw_smsk.s6_addr32[1])) ||
1041 (frwl->fw_src.s6_addr32[2] & (~frwl->fw_smsk.s6_addr32[2])) ||
1042 (frwl->fw_src.s6_addr32[3] & (~frwl->fw_smsk.s6_addr32[3])) ||
1043 (frwl->fw_dst.s6_addr32[0] & (~frwl->fw_dmsk.s6_addr32[0])) ||
1044 (frwl->fw_dst.s6_addr32[1] & (~frwl->fw_dmsk.s6_addr32[1])) ||
1045 (frwl->fw_dst.s6_addr32[2] & (~frwl->fw_dmsk.s6_addr32[2])) ||
1046 (frwl->fw_dst.s6_addr32[3] & (~frwl->fw_dmsk.s6_addr32[3]))) {
1047 dprintf(("%s rule never matches\n", err_prefix));
1048 return(NULL);
1049 }
1050
1051 if ((frwl->fw_flg & IPV6_FW_F_FRAG) &&
1052 (frwl->fw_prot == IPPROTO_UDP || frwl->fw_prot == IPPROTO_TCP)) {
1053 if (frwl->fw_nports) {
1054 dprintf(("%s cannot mix 'frag' and ports\n", err_prefix));
1055 return(NULL);
1056 }
1057 if (frwl->fw_prot == IPPROTO_TCP &&
1058 frwl->fw_tcpf != frwl->fw_tcpnf) {
1059 dprintf(("%s cannot mix 'frag' with TCP flags\n", err_prefix));
1060 return(NULL);
1061 }
1062 }
1063
1064 /* Check command specific stuff */
1065 switch (frwl->fw_flg & IPV6_FW_F_COMMAND)
1066 {
1067 case IPV6_FW_F_REJECT:
1068 if (frwl->fw_reject_code >= 0x100
1069 && !(frwl->fw_prot == IPPROTO_TCP
1070 && frwl->fw_reject_code == IPV6_FW_REJECT_RST)) {
1071 dprintf(("%s unknown reject code\n", err_prefix));
1072 return(NULL);
1073 }
1074 break;
1075 case IPV6_FW_F_DIVERT: /* Diverting to port zero is invalid */
1076 case IPV6_FW_F_TEE:
1077 if (frwl->fw_divert_port == 0) {
1078 dprintf(("%s can't divert to port 0\n", err_prefix));
1079 return (NULL);
1080 }
1081 break;
1082 case IPV6_FW_F_DENY:
1083 case IPV6_FW_F_ACCEPT:
1084 case IPV6_FW_F_COUNT:
1085 case IPV6_FW_F_SKIPTO:
1086 break;
1087 default:
1088 dprintf(("%s invalid command\n", err_prefix));
1089 return(NULL);
1090 }
1091
1092 return frwl;
1093 }
1094
1095 static int
ip6_fw_ctl(int stage,struct mbuf ** mm)1096 ip6_fw_ctl(int stage, struct mbuf **mm)
1097 {
1098 int error;
1099 struct mbuf *m;
1100
1101 if (stage == IPV6_FW_GET) {
1102 struct ip6_fw_chain *fcp = ip6_fw_chain.lh_first;
1103 *mm = m = m_get(M_WAITOK, MT_DATA); /* XXX */
1104 if (sizeof *(fcp->rule) > MLEN)
1105 MCLGET(m, M_WAITOK);
1106 for (; fcp; fcp = fcp->chain.le_next) {
1107 bcopy(fcp->rule, m->m_data, sizeof *(fcp->rule));
1108 m->m_len = sizeof *(fcp->rule);
1109 m->m_next = m_get(M_WAITOK, MT_DATA); /* XXX */
1110 m = m->m_next;
1111 if (sizeof *(fcp->rule) > MLEN)
1112 MCLGET(m, M_WAITOK);
1113 m->m_len = 0;
1114 }
1115 return (0);
1116 }
1117 m = *mm;
1118 /* only allow get calls if secure mode > 2 */
1119 if (securelevel > 2) {
1120 if (m) {
1121 m_freem(m);
1122 *mm = NULL;
1123 }
1124 return(EPERM);
1125 }
1126 if (stage == IPV6_FW_FLUSH) {
1127 while (ip6_fw_chain.lh_first != NULL &&
1128 ip6_fw_chain.lh_first->rule->fw_number != (u_short)-1) {
1129 struct ip6_fw_chain *fcp = ip6_fw_chain.lh_first;
1130 crit_enter();
1131 LIST_REMOVE(ip6_fw_chain.lh_first, chain);
1132 crit_exit();
1133 kfree(fcp->rule, M_IP6FW);
1134 kfree(fcp, M_IP6FW);
1135 }
1136 if (m) {
1137 m_freem(m);
1138 *mm = NULL;
1139 }
1140 return (0);
1141 }
1142 if (stage == IPV6_FW_ZERO) {
1143 error = zero_entry6(m);
1144 if (m) {
1145 m_freem(m);
1146 *mm = NULL;
1147 }
1148 return (error);
1149 }
1150 if (m == NULL) {
1151 kprintf("%s NULL mbuf ptr\n", err_prefix);
1152 return (EINVAL);
1153 }
1154
1155 if (stage == IPV6_FW_ADD) {
1156 struct ip6_fw *frwl = check_ip6fw_mbuf(m);
1157
1158 if (!frwl)
1159 error = EINVAL;
1160 else
1161 error = add_entry6(&ip6_fw_chain, frwl);
1162 if (m) {
1163 m_freem(m);
1164 *mm = NULL;
1165 }
1166 return error;
1167 }
1168 if (stage == IPV6_FW_DEL) {
1169 if (m->m_len != sizeof(struct ip6_fw)) {
1170 dprintf(("%s len=%d, want %d\n", err_prefix, m->m_len,
1171 (int)sizeof(struct ip6_fw)));
1172 error = EINVAL;
1173 } else if (mtod(m, struct ip6_fw *)->fw_number == (u_short)-1) {
1174 dprintf(("%s can't delete rule 65535\n", err_prefix));
1175 error = EINVAL;
1176 } else
1177 error = del_entry6(&ip6_fw_chain,
1178 mtod(m, struct ip6_fw *)->fw_number);
1179 if (m) {
1180 m_freem(m);
1181 *mm = NULL;
1182 }
1183 return error;
1184 }
1185
1186 dprintf(("%s unknown request %d\n", err_prefix, stage));
1187 if (m) {
1188 m_freem(m);
1189 *mm = NULL;
1190 }
1191 return (EINVAL);
1192 }
1193
1194 void
ip6_fw_init(void)1195 ip6_fw_init(void)
1196 {
1197 struct ip6_fw default_rule;
1198
1199 ip6_fw_chk_ptr = ip6_fw_chk;
1200 ip6_fw_ctl_ptr = ip6_fw_ctl;
1201 LIST_INIT(&ip6_fw_chain);
1202
1203 bzero(&default_rule, sizeof default_rule);
1204 default_rule.fw_prot = IPPROTO_IPV6;
1205 default_rule.fw_number = (u_short)-1;
1206 #ifdef IPV6FIREWALL_DEFAULT_TO_ACCEPT
1207 default_rule.fw_flg |= IPV6_FW_F_ACCEPT;
1208 #else
1209 default_rule.fw_flg |= IPV6_FW_F_DENY;
1210 #endif
1211 default_rule.fw_flg |= IPV6_FW_F_IN | IPV6_FW_F_OUT;
1212 if (check_ip6fw_struct(&default_rule) == NULL ||
1213 add_entry6(&ip6_fw_chain, &default_rule))
1214 panic(__func__);
1215
1216 kprintf("IPv6 packet filtering initialized, ");
1217 #ifdef IPV6FIREWALL_DEFAULT_TO_ACCEPT
1218 kprintf("default to accept, ");
1219 #endif
1220 #ifndef IPV6FIREWALL_VERBOSE
1221 kprintf("logging disabled\n");
1222 #else
1223 if (fw6_verbose_limit == 0)
1224 kprintf("unlimited logging\n");
1225 else
1226 kprintf("logging limited to %d packets/entry\n",
1227 fw6_verbose_limit);
1228 #endif
1229 }
1230
1231 static ip6_fw_chk_t *old_chk_ptr;
1232 static ip6_fw_ctl_t *old_ctl_ptr;
1233
1234 static int
ip6fw_modevent(module_t mod,int type,void * unused)1235 ip6fw_modevent(module_t mod, int type, void *unused)
1236 {
1237 switch (type) {
1238 case MOD_LOAD:
1239 crit_enter();
1240
1241 old_chk_ptr = ip6_fw_chk_ptr;
1242 old_ctl_ptr = ip6_fw_ctl_ptr;
1243
1244 ip6_fw_init();
1245 crit_exit();
1246 return 0;
1247 case MOD_UNLOAD:
1248 crit_enter();
1249 ip6_fw_chk_ptr = old_chk_ptr;
1250 ip6_fw_ctl_ptr = old_ctl_ptr;
1251 while (LIST_FIRST(&ip6_fw_chain) != NULL) {
1252 struct ip6_fw_chain *fcp = LIST_FIRST(&ip6_fw_chain);
1253 LIST_REMOVE(LIST_FIRST(&ip6_fw_chain), chain);
1254 kfree(fcp->rule, M_IP6FW);
1255 kfree(fcp, M_IP6FW);
1256 }
1257
1258 crit_exit();
1259 kprintf("IPv6 firewall unloaded\n");
1260 return 0;
1261 default:
1262 break;
1263 }
1264 return 0;
1265 }
1266
1267 static moduledata_t ip6fwmod = {
1268 "ip6fw",
1269 ip6fw_modevent,
1270 0
1271 };
1272 DECLARE_MODULE(ip6fw, ip6fwmod, SI_SUB_PSEUDO, SI_ORDER_ANY);
1273