xref: /freebsd/sys/netpfil/pf/pf_lb.c (revision 42249ef2)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2001 Daniel Hartmeier
5  * Copyright (c) 2002 - 2008 Henning Brauer
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  *
12  *    - Redistributions of source code must retain the above copyright
13  *      notice, this list of conditions and the following disclaimer.
14  *    - Redistributions in binary form must reproduce the above
15  *      copyright notice, this list of conditions and the following
16  *      disclaimer in the documentation and/or other materials provided
17  *      with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
23  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
25  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
27  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
29  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  *
32  * Effort sponsored in part by the Defense Advanced Research Projects
33  * Agency (DARPA) and Air Force Research Laboratory, Air Force
34  * Materiel Command, USAF, under agreement number F30602-01-2-0537.
35  *
36  *	$OpenBSD: pf_lb.c,v 1.2 2009/02/12 02:13:15 sthen Exp $
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include "opt_pf.h"
43 #include "opt_inet.h"
44 #include "opt_inet6.h"
45 
46 #include <sys/param.h>
47 #include <sys/lock.h>
48 #include <sys/mbuf.h>
49 #include <sys/socket.h>
50 #include <sys/sysctl.h>
51 
52 #include <net/if.h>
53 #include <net/vnet.h>
54 #include <net/pfvar.h>
55 #include <net/if_pflog.h>
56 
57 #define DPFPRINTF(n, x)	if (V_pf_status.debug >= (n)) printf x
58 
59 static void		 pf_hash(struct pf_addr *, struct pf_addr *,
60 			    struct pf_poolhashkey *, sa_family_t);
61 static struct pf_rule	*pf_match_translation(struct pf_pdesc *, struct mbuf *,
62 			    int, int, struct pfi_kif *,
63 			    struct pf_addr *, u_int16_t, struct pf_addr *,
64 			    uint16_t, int, struct pf_anchor_stackframe *);
65 static int pf_get_sport(sa_family_t, uint8_t, struct pf_rule *,
66     struct pf_addr *, uint16_t, struct pf_addr *, uint16_t, struct pf_addr *,
67     uint16_t *, uint16_t, uint16_t, struct pf_src_node **);
68 
69 #define mix(a,b,c) \
70 	do {					\
71 		a -= b; a -= c; a ^= (c >> 13);	\
72 		b -= c; b -= a; b ^= (a << 8);	\
73 		c -= a; c -= b; c ^= (b >> 13);	\
74 		a -= b; a -= c; a ^= (c >> 12);	\
75 		b -= c; b -= a; b ^= (a << 16);	\
76 		c -= a; c -= b; c ^= (b >> 5);	\
77 		a -= b; a -= c; a ^= (c >> 3);	\
78 		b -= c; b -= a; b ^= (a << 10);	\
79 		c -= a; c -= b; c ^= (b >> 15);	\
80 	} while (0)
81 
82 /*
83  * hash function based on bridge_hash in if_bridge.c
84  */
85 static void
86 pf_hash(struct pf_addr *inaddr, struct pf_addr *hash,
87     struct pf_poolhashkey *key, sa_family_t af)
88 {
89 	u_int32_t	a = 0x9e3779b9, b = 0x9e3779b9, c = key->key32[0];
90 
91 	switch (af) {
92 #ifdef INET
93 	case AF_INET:
94 		a += inaddr->addr32[0];
95 		b += key->key32[1];
96 		mix(a, b, c);
97 		hash->addr32[0] = c + key->key32[2];
98 		break;
99 #endif /* INET */
100 #ifdef INET6
101 	case AF_INET6:
102 		a += inaddr->addr32[0];
103 		b += inaddr->addr32[2];
104 		mix(a, b, c);
105 		hash->addr32[0] = c;
106 		a += inaddr->addr32[1];
107 		b += inaddr->addr32[3];
108 		c += key->key32[1];
109 		mix(a, b, c);
110 		hash->addr32[1] = c;
111 		a += inaddr->addr32[2];
112 		b += inaddr->addr32[1];
113 		c += key->key32[2];
114 		mix(a, b, c);
115 		hash->addr32[2] = c;
116 		a += inaddr->addr32[3];
117 		b += inaddr->addr32[0];
118 		c += key->key32[3];
119 		mix(a, b, c);
120 		hash->addr32[3] = c;
121 		break;
122 #endif /* INET6 */
123 	}
124 }
125 
126 static struct pf_rule *
127 pf_match_translation(struct pf_pdesc *pd, struct mbuf *m, int off,
128     int direction, struct pfi_kif *kif, struct pf_addr *saddr, u_int16_t sport,
129     struct pf_addr *daddr, uint16_t dport, int rs_num,
130     struct pf_anchor_stackframe *anchor_stack)
131 {
132 	struct pf_rule		*r, *rm = NULL;
133 	struct pf_ruleset	*ruleset = NULL;
134 	int			 tag = -1;
135 	int			 rtableid = -1;
136 	int			 asd = 0;
137 
138 	r = TAILQ_FIRST(pf_main_ruleset.rules[rs_num].active.ptr);
139 	while (r && rm == NULL) {
140 		struct pf_rule_addr	*src = NULL, *dst = NULL;
141 		struct pf_addr_wrap	*xdst = NULL;
142 
143 		if (r->action == PF_BINAT && direction == PF_IN) {
144 			src = &r->dst;
145 			if (r->rpool.cur != NULL)
146 				xdst = &r->rpool.cur->addr;
147 		} else {
148 			src = &r->src;
149 			dst = &r->dst;
150 		}
151 
152 		r->evaluations++;
153 		if (pfi_kif_match(r->kif, kif) == r->ifnot)
154 			r = r->skip[PF_SKIP_IFP].ptr;
155 		else if (r->direction && r->direction != direction)
156 			r = r->skip[PF_SKIP_DIR].ptr;
157 		else if (r->af && r->af != pd->af)
158 			r = r->skip[PF_SKIP_AF].ptr;
159 		else if (r->proto && r->proto != pd->proto)
160 			r = r->skip[PF_SKIP_PROTO].ptr;
161 		else if (PF_MISMATCHAW(&src->addr, saddr, pd->af,
162 		    src->neg, kif, M_GETFIB(m)))
163 			r = r->skip[src == &r->src ? PF_SKIP_SRC_ADDR :
164 			    PF_SKIP_DST_ADDR].ptr;
165 		else if (src->port_op && !pf_match_port(src->port_op,
166 		    src->port[0], src->port[1], sport))
167 			r = r->skip[src == &r->src ? PF_SKIP_SRC_PORT :
168 			    PF_SKIP_DST_PORT].ptr;
169 		else if (dst != NULL &&
170 		    PF_MISMATCHAW(&dst->addr, daddr, pd->af, dst->neg, NULL,
171 		    M_GETFIB(m)))
172 			r = r->skip[PF_SKIP_DST_ADDR].ptr;
173 		else if (xdst != NULL && PF_MISMATCHAW(xdst, daddr, pd->af,
174 		    0, NULL, M_GETFIB(m)))
175 			r = TAILQ_NEXT(r, entries);
176 		else if (dst != NULL && dst->port_op &&
177 		    !pf_match_port(dst->port_op, dst->port[0],
178 		    dst->port[1], dport))
179 			r = r->skip[PF_SKIP_DST_PORT].ptr;
180 		else if (r->match_tag && !pf_match_tag(m, r, &tag,
181 		    pd->pf_mtag ? pd->pf_mtag->tag : 0))
182 			r = TAILQ_NEXT(r, entries);
183 		else if (r->os_fingerprint != PF_OSFP_ANY && (pd->proto !=
184 		    IPPROTO_TCP || !pf_osfp_match(pf_osfp_fingerprint(pd, m,
185 		    off, pd->hdr.tcp), r->os_fingerprint)))
186 			r = TAILQ_NEXT(r, entries);
187 		else {
188 			if (r->tag)
189 				tag = r->tag;
190 			if (r->rtableid >= 0)
191 				rtableid = r->rtableid;
192 			if (r->anchor == NULL) {
193 				rm = r;
194 			} else
195 				pf_step_into_anchor(anchor_stack, &asd,
196 				    &ruleset, rs_num, &r, NULL, NULL);
197 		}
198 		if (r == NULL)
199 			pf_step_out_of_anchor(anchor_stack, &asd, &ruleset,
200 			    rs_num, &r, NULL, NULL);
201 	}
202 
203 	if (tag > 0 && pf_tag_packet(m, pd, tag))
204 		return (NULL);
205 	if (rtableid >= 0)
206 		M_SETFIB(m, rtableid);
207 
208 	if (rm != NULL && (rm->action == PF_NONAT ||
209 	    rm->action == PF_NORDR || rm->action == PF_NOBINAT))
210 		return (NULL);
211 	return (rm);
212 }
213 
214 static int
215 pf_get_sport(sa_family_t af, u_int8_t proto, struct pf_rule *r,
216     struct pf_addr *saddr, uint16_t sport, struct pf_addr *daddr,
217     uint16_t dport, struct pf_addr *naddr, uint16_t *nport, uint16_t low,
218     uint16_t high, struct pf_src_node **sn)
219 {
220 	struct pf_state_key_cmp	key;
221 	struct pf_addr		init_addr;
222 
223 	bzero(&init_addr, sizeof(init_addr));
224 	if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
225 		return (1);
226 
227 	if (proto == IPPROTO_ICMP) {
228 		low = 1;
229 		high = 65535;
230 	}
231 
232 	bzero(&key, sizeof(key));
233 	key.af = af;
234 	key.proto = proto;
235 	key.port[0] = dport;
236 	PF_ACPY(&key.addr[0], daddr, key.af);
237 
238 	do {
239 		PF_ACPY(&key.addr[1], naddr, key.af);
240 
241 		/*
242 		 * port search; start random, step;
243 		 * similar 2 portloop in in_pcbbind
244 		 */
245 		if (!(proto == IPPROTO_TCP || proto == IPPROTO_UDP ||
246 		    proto == IPPROTO_ICMP) || (low == 0 && high == 0)) {
247 			/*
248 			 * XXX bug: icmp states don't use the id on both sides.
249 			 * (traceroute -I through nat)
250 			 */
251 			key.port[1] = sport;
252 			if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
253 				*nport = sport;
254 				return (0);
255 			}
256 		} else if (low == high) {
257 			key.port[1] = htons(low);
258 			if (pf_find_state_all(&key, PF_IN, NULL) == NULL) {
259 				*nport = htons(low);
260 				return (0);
261 			}
262 		} else {
263 			uint32_t tmp;
264 			uint16_t cut;
265 
266 			if (low > high) {
267 				tmp = low;
268 				low = high;
269 				high = tmp;
270 			}
271 			/* low < high */
272 			cut = arc4random() % (1 + high - low) + low;
273 			/* low <= cut <= high */
274 			for (tmp = cut; tmp <= high && tmp <= 0xffff; ++tmp) {
275 				key.port[1] = htons(tmp);
276 				if (pf_find_state_all(&key, PF_IN, NULL) ==
277 				    NULL) {
278 					*nport = htons(tmp);
279 					return (0);
280 				}
281 			}
282 			tmp = cut;
283 			for (tmp -= 1; tmp >= low && tmp <= 0xffff; --tmp) {
284 				key.port[1] = htons(tmp);
285 				if (pf_find_state_all(&key, PF_IN, NULL) ==
286 				    NULL) {
287 					*nport = htons(tmp);
288 					return (0);
289 				}
290 			}
291 		}
292 
293 		switch (r->rpool.opts & PF_POOL_TYPEMASK) {
294 		case PF_POOL_RANDOM:
295 		case PF_POOL_ROUNDROBIN:
296 			/*
297 			 * pick a different source address since we're out
298 			 * of free port choices for the current one.
299 			 */
300 			if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
301 				return (1);
302 			break;
303 		case PF_POOL_NONE:
304 		case PF_POOL_SRCHASH:
305 		case PF_POOL_BITMASK:
306 		default:
307 			return (1);
308 		}
309 	} while (! PF_AEQ(&init_addr, naddr, af) );
310 	return (1);					/* none available */
311 }
312 
313 int
314 pf_map_addr(sa_family_t af, struct pf_rule *r, struct pf_addr *saddr,
315     struct pf_addr *naddr, struct pf_addr *init_addr, struct pf_src_node **sn)
316 {
317 	struct pf_pool		*rpool = &r->rpool;
318 	struct pf_addr		*raddr = NULL, *rmask = NULL;
319 
320 	/* Try to find a src_node if none was given and this
321 	   is a sticky-address rule. */
322 	if (*sn == NULL && r->rpool.opts & PF_POOL_STICKYADDR &&
323 	    (r->rpool.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE)
324 		*sn = pf_find_src_node(saddr, r, af, 0);
325 
326 	/* If a src_node was found or explicitly given and it has a non-zero
327 	   route address, use this address. A zeroed address is found if the
328 	   src node was created just a moment ago in pf_create_state and it
329 	   needs to be filled in with routing decision calculated here. */
330 	if (*sn != NULL && !PF_AZERO(&(*sn)->raddr, af)) {
331 		/* If the supplied address is the same as the current one we've
332 		 * been asked before, so tell the caller that there's no other
333 		 * address to be had. */
334 		if (PF_AEQ(naddr, &(*sn)->raddr, af))
335 			return (1);
336 
337 		PF_ACPY(naddr, &(*sn)->raddr, af);
338 		if (V_pf_status.debug >= PF_DEBUG_MISC) {
339 			printf("pf_map_addr: src tracking maps ");
340 			pf_print_host(saddr, 0, af);
341 			printf(" to ");
342 			pf_print_host(naddr, 0, af);
343 			printf("\n");
344 		}
345 		return (0);
346 	}
347 
348 	/* Find the route using chosen algorithm. Store the found route
349 	   in src_node if it was given or found. */
350 	if (rpool->cur->addr.type == PF_ADDR_NOROUTE)
351 		return (1);
352 	if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
353 		switch (af) {
354 #ifdef INET
355 		case AF_INET:
356 			if (rpool->cur->addr.p.dyn->pfid_acnt4 < 1 &&
357 			    (rpool->opts & PF_POOL_TYPEMASK) !=
358 			    PF_POOL_ROUNDROBIN)
359 				return (1);
360 			 raddr = &rpool->cur->addr.p.dyn->pfid_addr4;
361 			 rmask = &rpool->cur->addr.p.dyn->pfid_mask4;
362 			break;
363 #endif /* INET */
364 #ifdef INET6
365 		case AF_INET6:
366 			if (rpool->cur->addr.p.dyn->pfid_acnt6 < 1 &&
367 			    (rpool->opts & PF_POOL_TYPEMASK) !=
368 			    PF_POOL_ROUNDROBIN)
369 				return (1);
370 			raddr = &rpool->cur->addr.p.dyn->pfid_addr6;
371 			rmask = &rpool->cur->addr.p.dyn->pfid_mask6;
372 			break;
373 #endif /* INET6 */
374 		}
375 	} else if (rpool->cur->addr.type == PF_ADDR_TABLE) {
376 		if ((rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_ROUNDROBIN)
377 			return (1); /* unsupported */
378 	} else {
379 		raddr = &rpool->cur->addr.v.a.addr;
380 		rmask = &rpool->cur->addr.v.a.mask;
381 	}
382 
383 	switch (rpool->opts & PF_POOL_TYPEMASK) {
384 	case PF_POOL_NONE:
385 		PF_ACPY(naddr, raddr, af);
386 		break;
387 	case PF_POOL_BITMASK:
388 		PF_POOLMASK(naddr, raddr, rmask, saddr, af);
389 		break;
390 	case PF_POOL_RANDOM:
391 		if (init_addr != NULL && PF_AZERO(init_addr, af)) {
392 			switch (af) {
393 #ifdef INET
394 			case AF_INET:
395 				rpool->counter.addr32[0] = htonl(arc4random());
396 				break;
397 #endif /* INET */
398 #ifdef INET6
399 			case AF_INET6:
400 				if (rmask->addr32[3] != 0xffffffff)
401 					rpool->counter.addr32[3] =
402 					    htonl(arc4random());
403 				else
404 					break;
405 				if (rmask->addr32[2] != 0xffffffff)
406 					rpool->counter.addr32[2] =
407 					    htonl(arc4random());
408 				else
409 					break;
410 				if (rmask->addr32[1] != 0xffffffff)
411 					rpool->counter.addr32[1] =
412 					    htonl(arc4random());
413 				else
414 					break;
415 				if (rmask->addr32[0] != 0xffffffff)
416 					rpool->counter.addr32[0] =
417 					    htonl(arc4random());
418 				break;
419 #endif /* INET6 */
420 			}
421 			PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
422 			PF_ACPY(init_addr, naddr, af);
423 
424 		} else {
425 			PF_AINC(&rpool->counter, af);
426 			PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
427 		}
428 		break;
429 	case PF_POOL_SRCHASH:
430 	    {
431 		unsigned char hash[16];
432 
433 		pf_hash(saddr, (struct pf_addr *)&hash, &rpool->key, af);
434 		PF_POOLMASK(naddr, raddr, rmask, (struct pf_addr *)&hash, af);
435 		break;
436 	    }
437 	case PF_POOL_ROUNDROBIN:
438 	    {
439 		struct pf_pooladdr *acur = rpool->cur;
440 
441 		/*
442 		 * XXXGL: in the round-robin case we need to store
443 		 * the round-robin machine state in the rule, thus
444 		 * forwarding thread needs to modify rule.
445 		 *
446 		 * This is done w/o locking, because performance is assumed
447 		 * more important than round-robin precision.
448 		 *
449 		 * In the simpliest case we just update the "rpool->cur"
450 		 * pointer. However, if pool contains tables or dynamic
451 		 * addresses, then "tblidx" is also used to store machine
452 		 * state. Since "tblidx" is int, concurrent access to it can't
453 		 * lead to inconsistence, only to lost of precision.
454 		 *
455 		 * Things get worse, if table contains not hosts, but
456 		 * prefixes. In this case counter also stores machine state,
457 		 * and for IPv6 address, counter can't be updated atomically.
458 		 * Probably, using round-robin on a table containing IPv6
459 		 * prefixes (or even IPv4) would cause a panic.
460 		 */
461 
462 		if (rpool->cur->addr.type == PF_ADDR_TABLE) {
463 			if (!pfr_pool_get(rpool->cur->addr.p.tbl,
464 			    &rpool->tblidx, &rpool->counter, af))
465 				goto get_addr;
466 		} else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
467 			if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
468 			    &rpool->tblidx, &rpool->counter, af))
469 				goto get_addr;
470 		} else if (pf_match_addr(0, raddr, rmask, &rpool->counter, af))
471 			goto get_addr;
472 
473 	try_next:
474 		if (TAILQ_NEXT(rpool->cur, entries) == NULL)
475 			rpool->cur = TAILQ_FIRST(&rpool->list);
476 		else
477 			rpool->cur = TAILQ_NEXT(rpool->cur, entries);
478 		if (rpool->cur->addr.type == PF_ADDR_TABLE) {
479 			rpool->tblidx = -1;
480 			if (pfr_pool_get(rpool->cur->addr.p.tbl,
481 			    &rpool->tblidx, &rpool->counter, af)) {
482 				/* table contains no address of type 'af' */
483 				if (rpool->cur != acur)
484 					goto try_next;
485 				return (1);
486 			}
487 		} else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
488 			rpool->tblidx = -1;
489 			if (pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
490 			    &rpool->tblidx, &rpool->counter, af)) {
491 				/* table contains no address of type 'af' */
492 				if (rpool->cur != acur)
493 					goto try_next;
494 				return (1);
495 			}
496 		} else {
497 			raddr = &rpool->cur->addr.v.a.addr;
498 			rmask = &rpool->cur->addr.v.a.mask;
499 			PF_ACPY(&rpool->counter, raddr, af);
500 		}
501 
502 	get_addr:
503 		PF_ACPY(naddr, &rpool->counter, af);
504 		if (init_addr != NULL && PF_AZERO(init_addr, af))
505 			PF_ACPY(init_addr, naddr, af);
506 		PF_AINC(&rpool->counter, af);
507 		break;
508 	    }
509 	}
510 	if (*sn != NULL)
511 		PF_ACPY(&(*sn)->raddr, naddr, af);
512 
513 	if (V_pf_status.debug >= PF_DEBUG_MISC &&
514 	    (rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) {
515 		printf("pf_map_addr: selected address ");
516 		pf_print_host(naddr, 0, af);
517 		printf("\n");
518 	}
519 
520 	return (0);
521 }
522 
523 struct pf_rule *
524 pf_get_translation(struct pf_pdesc *pd, struct mbuf *m, int off, int direction,
525     struct pfi_kif *kif, struct pf_src_node **sn,
526     struct pf_state_key **skp, struct pf_state_key **nkp,
527     struct pf_addr *saddr, struct pf_addr *daddr,
528     uint16_t sport, uint16_t dport, struct pf_anchor_stackframe *anchor_stack)
529 {
530 	struct pf_rule	*r = NULL;
531 	struct pf_addr	*naddr;
532 	uint16_t	*nport;
533 
534 	PF_RULES_RASSERT();
535 	KASSERT(*skp == NULL, ("*skp not NULL"));
536 	KASSERT(*nkp == NULL, ("*nkp not NULL"));
537 
538 	if (direction == PF_OUT) {
539 		r = pf_match_translation(pd, m, off, direction, kif, saddr,
540 		    sport, daddr, dport, PF_RULESET_BINAT, anchor_stack);
541 		if (r == NULL)
542 			r = pf_match_translation(pd, m, off, direction, kif,
543 			    saddr, sport, daddr, dport, PF_RULESET_NAT,
544 			    anchor_stack);
545 	} else {
546 		r = pf_match_translation(pd, m, off, direction, kif, saddr,
547 		    sport, daddr, dport, PF_RULESET_RDR, anchor_stack);
548 		if (r == NULL)
549 			r = pf_match_translation(pd, m, off, direction, kif,
550 			    saddr, sport, daddr, dport, PF_RULESET_BINAT,
551 			    anchor_stack);
552 	}
553 
554 	if (r == NULL)
555 		return (NULL);
556 
557 	switch (r->action) {
558 	case PF_NONAT:
559 	case PF_NOBINAT:
560 	case PF_NORDR:
561 		return (NULL);
562 	}
563 
564 	*skp = pf_state_key_setup(pd, saddr, daddr, sport, dport);
565 	if (*skp == NULL)
566 		return (NULL);
567 	*nkp = pf_state_key_clone(*skp);
568 	if (*nkp == NULL) {
569 		uma_zfree(V_pf_state_key_z, *skp);
570 		*skp = NULL;
571 		return (NULL);
572 	}
573 
574 	/* XXX We only modify one side for now. */
575 	naddr = &(*nkp)->addr[1];
576 	nport = &(*nkp)->port[1];
577 
578 	switch (r->action) {
579 	case PF_NAT:
580 		if (pf_get_sport(pd->af, pd->proto, r, saddr, sport, daddr,
581 		    dport, naddr, nport, r->rpool.proxy_port[0],
582 		    r->rpool.proxy_port[1], sn)) {
583 			DPFPRINTF(PF_DEBUG_MISC,
584 			    ("pf: NAT proxy port allocation (%u-%u) failed\n",
585 			    r->rpool.proxy_port[0], r->rpool.proxy_port[1]));
586 			goto notrans;
587 		}
588 		break;
589 	case PF_BINAT:
590 		switch (direction) {
591 		case PF_OUT:
592 			if (r->rpool.cur->addr.type == PF_ADDR_DYNIFTL){
593 				switch (pd->af) {
594 #ifdef INET
595 				case AF_INET:
596 					if (r->rpool.cur->addr.p.dyn->
597 					    pfid_acnt4 < 1)
598 						goto notrans;
599 					PF_POOLMASK(naddr,
600 					    &r->rpool.cur->addr.p.dyn->
601 					    pfid_addr4,
602 					    &r->rpool.cur->addr.p.dyn->
603 					    pfid_mask4, saddr, AF_INET);
604 					break;
605 #endif /* INET */
606 #ifdef INET6
607 				case AF_INET6:
608 					if (r->rpool.cur->addr.p.dyn->
609 					    pfid_acnt6 < 1)
610 						goto notrans;
611 					PF_POOLMASK(naddr,
612 					    &r->rpool.cur->addr.p.dyn->
613 					    pfid_addr6,
614 					    &r->rpool.cur->addr.p.dyn->
615 					    pfid_mask6, saddr, AF_INET6);
616 					break;
617 #endif /* INET6 */
618 				}
619 			} else
620 				PF_POOLMASK(naddr,
621 				    &r->rpool.cur->addr.v.a.addr,
622 				    &r->rpool.cur->addr.v.a.mask, saddr,
623 				    pd->af);
624 			break;
625 		case PF_IN:
626 			if (r->src.addr.type == PF_ADDR_DYNIFTL) {
627 				switch (pd->af) {
628 #ifdef INET
629 				case AF_INET:
630 					if (r->src.addr.p.dyn-> pfid_acnt4 < 1)
631 						goto notrans;
632 					PF_POOLMASK(naddr,
633 					    &r->src.addr.p.dyn->pfid_addr4,
634 					    &r->src.addr.p.dyn->pfid_mask4,
635 					    daddr, AF_INET);
636 					break;
637 #endif /* INET */
638 #ifdef INET6
639 				case AF_INET6:
640 					if (r->src.addr.p.dyn->pfid_acnt6 < 1)
641 						goto notrans;
642 					PF_POOLMASK(naddr,
643 					    &r->src.addr.p.dyn->pfid_addr6,
644 					    &r->src.addr.p.dyn->pfid_mask6,
645 					    daddr, AF_INET6);
646 					break;
647 #endif /* INET6 */
648 				}
649 			} else
650 				PF_POOLMASK(naddr, &r->src.addr.v.a.addr,
651 				    &r->src.addr.v.a.mask, daddr, pd->af);
652 			break;
653 		}
654 		break;
655 	case PF_RDR: {
656 		if (pf_map_addr(pd->af, r, saddr, naddr, NULL, sn))
657 			goto notrans;
658 		if ((r->rpool.opts & PF_POOL_TYPEMASK) == PF_POOL_BITMASK)
659 			PF_POOLMASK(naddr, naddr, &r->rpool.cur->addr.v.a.mask,
660 			    daddr, pd->af);
661 
662 		if (r->rpool.proxy_port[1]) {
663 			uint32_t	tmp_nport;
664 
665 			tmp_nport = ((ntohs(dport) - ntohs(r->dst.port[0])) %
666 			    (r->rpool.proxy_port[1] - r->rpool.proxy_port[0] +
667 			    1)) + r->rpool.proxy_port[0];
668 
669 			/* Wrap around if necessary. */
670 			if (tmp_nport > 65535)
671 				tmp_nport -= 65535;
672 			*nport = htons((uint16_t)tmp_nport);
673 		} else if (r->rpool.proxy_port[0])
674 			*nport = htons(r->rpool.proxy_port[0]);
675 		break;
676 	}
677 	default:
678 		panic("%s: unknown action %u", __func__, r->action);
679 	}
680 
681 	/* Return success only if translation really happened. */
682 	if (bcmp(*skp, *nkp, sizeof(struct pf_state_key_cmp)))
683 		return (r);
684 
685 notrans:
686 	uma_zfree(V_pf_state_key_z, *nkp);
687 	uma_zfree(V_pf_state_key_z, *skp);
688 	*skp = *nkp = NULL;
689 	*sn = NULL;
690 
691 	return (NULL);
692 }
693