xref: /freebsd/sys/netpfil/pf/pf_lb.c (revision 87384c51e047349fdbcf4f07fe52d900ce108040)
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_krule	*pf_match_translation(struct pf_pdesc *, struct mbuf *,
62 			    int, int, struct pfi_kkif *,
63 			    struct pf_addr *, u_int16_t, struct pf_addr *,
64 			    uint16_t, int, struct pf_kanchor_stackframe *);
65 static int pf_get_sport(sa_family_t, uint8_t, struct pf_krule *,
66     struct pf_addr *, uint16_t, struct pf_addr *, uint16_t, struct pf_addr *,
67     uint16_t *, uint16_t, uint16_t, struct pf_ksrc_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_krule *
127 pf_match_translation(struct pf_pdesc *pd, struct mbuf *m, int off,
128     int direction, struct pfi_kkif *kif, struct pf_addr *saddr, u_int16_t sport,
129     struct pf_addr *daddr, uint16_t dport, int rs_num,
130     struct pf_kanchor_stackframe *anchor_stack)
131 {
132 	struct pf_krule		*r, *rm = NULL;
133 	struct pf_kruleset	*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 != 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 		pf_counter_u64_add(&r->evaluations, 1);
153 		if (pfi_kkif_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 				if (rm->action == PF_NONAT ||
195 				    rm->action == PF_NORDR ||
196 				    rm->action == PF_NOBINAT) {
197 					rm = NULL;
198 				}
199 				break;
200 			} else
201 				pf_step_into_anchor(anchor_stack, &asd,
202 				    &ruleset, rs_num, &r, NULL, NULL);
203 		}
204 		if (r == NULL)
205 			pf_step_out_of_anchor(anchor_stack, &asd, &ruleset,
206 			    rs_num, &r, NULL, NULL);
207 	}
208 
209 	if (tag > 0 && pf_tag_packet(m, pd, tag))
210 		return (NULL);
211 	if (rtableid >= 0)
212 		M_SETFIB(m, rtableid);
213 
214 	return (rm);
215 }
216 
217 static int
218 pf_get_sport(sa_family_t af, u_int8_t proto, struct pf_krule *r,
219     struct pf_addr *saddr, uint16_t sport, struct pf_addr *daddr,
220     uint16_t dport, struct pf_addr *naddr, uint16_t *nport, uint16_t low,
221     uint16_t high, struct pf_ksrc_node **sn)
222 {
223 	struct pf_state_key_cmp	key;
224 	struct pf_addr		init_addr;
225 
226 	bzero(&init_addr, sizeof(init_addr));
227 	if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
228 		return (1);
229 
230 	bzero(&key, sizeof(key));
231 	key.af = af;
232 	key.proto = proto;
233 	key.port[0] = dport;
234 	PF_ACPY(&key.addr[0], daddr, key.af);
235 
236 	do {
237 		PF_ACPY(&key.addr[1], naddr, key.af);
238 
239 		/*
240 		 * port search; start random, step;
241 		 * similar 2 portloop in in_pcbbind
242 		 */
243 		if (!(proto == IPPROTO_TCP || proto == IPPROTO_UDP ||
244 		    proto == IPPROTO_ICMP) || (low == 0 && high == 0)) {
245 			/*
246 			 * XXX bug: icmp states don't use the id on both sides.
247 			 * (traceroute -I through nat)
248 			 */
249 			key.port[1] = sport;
250 			if (!pf_find_state_all_exists(&key, PF_IN)) {
251 				*nport = sport;
252 				return (0);
253 			}
254 		} else if (low == high) {
255 			key.port[1] = htons(low);
256 			if (!pf_find_state_all_exists(&key, PF_IN)) {
257 				*nport = htons(low);
258 				return (0);
259 			}
260 		} else {
261 			uint32_t tmp;
262 			uint16_t cut;
263 
264 			if (low > high) {
265 				tmp = low;
266 				low = high;
267 				high = tmp;
268 			}
269 			/* low < high */
270 			cut = arc4random() % (1 + high - low) + low;
271 			/* low <= cut <= high */
272 			for (tmp = cut; tmp <= high && tmp <= 0xffff; ++tmp) {
273 				key.port[1] = htons(tmp);
274 				if (!pf_find_state_all_exists(&key, PF_IN)) {
275 					*nport = htons(tmp);
276 					return (0);
277 				}
278 			}
279 			tmp = cut;
280 			for (tmp -= 1; tmp >= low && tmp <= 0xffff; --tmp) {
281 				key.port[1] = htons(tmp);
282 				if (!pf_find_state_all_exists(&key, PF_IN)) {
283 					*nport = htons(tmp);
284 					return (0);
285 				}
286 			}
287 		}
288 
289 		switch (r->rpool.opts & PF_POOL_TYPEMASK) {
290 		case PF_POOL_RANDOM:
291 		case PF_POOL_ROUNDROBIN:
292 			/*
293 			 * pick a different source address since we're out
294 			 * of free port choices for the current one.
295 			 */
296 			if (pf_map_addr(af, r, saddr, naddr, &init_addr, sn))
297 				return (1);
298 			break;
299 		case PF_POOL_NONE:
300 		case PF_POOL_SRCHASH:
301 		case PF_POOL_BITMASK:
302 		default:
303 			return (1);
304 		}
305 	} while (! PF_AEQ(&init_addr, naddr, af) );
306 	return (1);					/* none available */
307 }
308 
309 static int
310 pf_get_mape_sport(sa_family_t af, u_int8_t proto, struct pf_krule *r,
311     struct pf_addr *saddr, uint16_t sport, struct pf_addr *daddr,
312     uint16_t dport, struct pf_addr *naddr, uint16_t *nport,
313     struct pf_ksrc_node **sn)
314 {
315 	uint16_t psmask, low, highmask;
316 	uint16_t i, ahigh, cut;
317 	int ashift, psidshift;
318 
319 	ashift = 16 - r->rpool.mape.offset;
320 	psidshift = ashift - r->rpool.mape.psidlen;
321 	psmask = r->rpool.mape.psid & ((1U << r->rpool.mape.psidlen) - 1);
322 	psmask = psmask << psidshift;
323 	highmask = (1U << psidshift) - 1;
324 
325 	ahigh = (1U << r->rpool.mape.offset) - 1;
326 	cut = arc4random() & ahigh;
327 	if (cut == 0)
328 		cut = 1;
329 
330 	for (i = cut; i <= ahigh; i++) {
331 		low = (i << ashift) | psmask;
332 		if (!pf_get_sport(af, proto, r, saddr, sport, daddr, dport,
333 		    naddr, nport, low, low | highmask, sn))
334 			return (0);
335 	}
336 	for (i = cut - 1; i > 0; i--) {
337 		low = (i << ashift) | psmask;
338 		if (!pf_get_sport(af, proto, r, saddr, sport, daddr, dport,
339 		    naddr, nport, low, low | highmask, sn))
340 			return (0);
341 	}
342 	return (1);
343 }
344 
345 int
346 pf_map_addr(sa_family_t af, struct pf_krule *r, struct pf_addr *saddr,
347     struct pf_addr *naddr, struct pf_addr *init_addr, struct pf_ksrc_node **sn)
348 {
349 	struct pf_kpool		*rpool = &r->rpool;
350 	struct pf_addr		*raddr = NULL, *rmask = NULL;
351 
352 	/* Try to find a src_node if none was given and this
353 	   is a sticky-address rule. */
354 	if (*sn == NULL && r->rpool.opts & PF_POOL_STICKYADDR &&
355 	    (r->rpool.opts & PF_POOL_TYPEMASK) != PF_POOL_NONE)
356 		*sn = pf_find_src_node(saddr, r, af, 0);
357 
358 	/* If a src_node was found or explicitly given and it has a non-zero
359 	   route address, use this address. A zeroed address is found if the
360 	   src node was created just a moment ago in pf_create_state and it
361 	   needs to be filled in with routing decision calculated here. */
362 	if (*sn != NULL && !PF_AZERO(&(*sn)->raddr, af)) {
363 		/* If the supplied address is the same as the current one we've
364 		 * been asked before, so tell the caller that there's no other
365 		 * address to be had. */
366 		if (PF_AEQ(naddr, &(*sn)->raddr, af))
367 			return (1);
368 
369 		PF_ACPY(naddr, &(*sn)->raddr, af);
370 		if (V_pf_status.debug >= PF_DEBUG_NOISY) {
371 			printf("pf_map_addr: src tracking maps ");
372 			pf_print_host(saddr, 0, af);
373 			printf(" to ");
374 			pf_print_host(naddr, 0, af);
375 			printf("\n");
376 		}
377 		return (0);
378 	}
379 
380 	mtx_lock(&rpool->mtx);
381 	/* Find the route using chosen algorithm. Store the found route
382 	   in src_node if it was given or found. */
383 	if (rpool->cur->addr.type == PF_ADDR_NOROUTE) {
384 		mtx_unlock(&rpool->mtx);
385 		return (1);
386 	}
387 	if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
388 		switch (af) {
389 #ifdef INET
390 		case AF_INET:
391 			if (rpool->cur->addr.p.dyn->pfid_acnt4 < 1 &&
392 			    (rpool->opts & PF_POOL_TYPEMASK) !=
393 			    PF_POOL_ROUNDROBIN) {
394 				mtx_unlock(&rpool->mtx);
395 				return (1);
396 			}
397 			raddr = &rpool->cur->addr.p.dyn->pfid_addr4;
398 			rmask = &rpool->cur->addr.p.dyn->pfid_mask4;
399 			break;
400 #endif /* INET */
401 #ifdef INET6
402 		case AF_INET6:
403 			if (rpool->cur->addr.p.dyn->pfid_acnt6 < 1 &&
404 			    (rpool->opts & PF_POOL_TYPEMASK) !=
405 			    PF_POOL_ROUNDROBIN) {
406 				mtx_unlock(&rpool->mtx);
407 				return (1);
408 			}
409 			raddr = &rpool->cur->addr.p.dyn->pfid_addr6;
410 			rmask = &rpool->cur->addr.p.dyn->pfid_mask6;
411 			break;
412 #endif /* INET6 */
413 		}
414 	} else if (rpool->cur->addr.type == PF_ADDR_TABLE) {
415 		if ((rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_ROUNDROBIN) {
416 			mtx_unlock(&rpool->mtx);
417 			return (1); /* unsupported */
418 		}
419 	} else {
420 		raddr = &rpool->cur->addr.v.a.addr;
421 		rmask = &rpool->cur->addr.v.a.mask;
422 	}
423 
424 	switch (rpool->opts & PF_POOL_TYPEMASK) {
425 	case PF_POOL_NONE:
426 		PF_ACPY(naddr, raddr, af);
427 		break;
428 	case PF_POOL_BITMASK:
429 		PF_POOLMASK(naddr, raddr, rmask, saddr, af);
430 		break;
431 	case PF_POOL_RANDOM:
432 		if (init_addr != NULL && PF_AZERO(init_addr, af)) {
433 			switch (af) {
434 #ifdef INET
435 			case AF_INET:
436 				rpool->counter.addr32[0] = htonl(arc4random());
437 				break;
438 #endif /* INET */
439 #ifdef INET6
440 			case AF_INET6:
441 				if (rmask->addr32[3] != 0xffffffff)
442 					rpool->counter.addr32[3] =
443 					    htonl(arc4random());
444 				else
445 					break;
446 				if (rmask->addr32[2] != 0xffffffff)
447 					rpool->counter.addr32[2] =
448 					    htonl(arc4random());
449 				else
450 					break;
451 				if (rmask->addr32[1] != 0xffffffff)
452 					rpool->counter.addr32[1] =
453 					    htonl(arc4random());
454 				else
455 					break;
456 				if (rmask->addr32[0] != 0xffffffff)
457 					rpool->counter.addr32[0] =
458 					    htonl(arc4random());
459 				break;
460 #endif /* INET6 */
461 			}
462 			PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
463 			PF_ACPY(init_addr, naddr, af);
464 
465 		} else {
466 			PF_AINC(&rpool->counter, af);
467 			PF_POOLMASK(naddr, raddr, rmask, &rpool->counter, af);
468 		}
469 		break;
470 	case PF_POOL_SRCHASH:
471 	    {
472 		unsigned char hash[16];
473 
474 		pf_hash(saddr, (struct pf_addr *)&hash, &rpool->key, af);
475 		PF_POOLMASK(naddr, raddr, rmask, (struct pf_addr *)&hash, af);
476 		break;
477 	    }
478 	case PF_POOL_ROUNDROBIN:
479 	    {
480 		struct pf_kpooladdr *acur = rpool->cur;
481 
482 		if (rpool->cur->addr.type == PF_ADDR_TABLE) {
483 			if (!pfr_pool_get(rpool->cur->addr.p.tbl,
484 			    &rpool->tblidx, &rpool->counter, af))
485 				goto get_addr;
486 		} else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
487 			if (!pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
488 			    &rpool->tblidx, &rpool->counter, af))
489 				goto get_addr;
490 		} else if (pf_match_addr(0, raddr, rmask, &rpool->counter, af))
491 			goto get_addr;
492 
493 	try_next:
494 		if (TAILQ_NEXT(rpool->cur, entries) == NULL)
495 			rpool->cur = TAILQ_FIRST(&rpool->list);
496 		else
497 			rpool->cur = TAILQ_NEXT(rpool->cur, entries);
498 		if (rpool->cur->addr.type == PF_ADDR_TABLE) {
499 			rpool->tblidx = -1;
500 			if (pfr_pool_get(rpool->cur->addr.p.tbl,
501 			    &rpool->tblidx, &rpool->counter, af)) {
502 				/* table contains no address of type 'af' */
503 				if (rpool->cur != acur)
504 					goto try_next;
505 				mtx_unlock(&rpool->mtx);
506 				return (1);
507 			}
508 		} else if (rpool->cur->addr.type == PF_ADDR_DYNIFTL) {
509 			rpool->tblidx = -1;
510 			if (pfr_pool_get(rpool->cur->addr.p.dyn->pfid_kt,
511 			    &rpool->tblidx, &rpool->counter, af)) {
512 				/* table contains no address of type 'af' */
513 				if (rpool->cur != acur)
514 					goto try_next;
515 				mtx_unlock(&rpool->mtx);
516 				return (1);
517 			}
518 		} else {
519 			raddr = &rpool->cur->addr.v.a.addr;
520 			rmask = &rpool->cur->addr.v.a.mask;
521 			PF_ACPY(&rpool->counter, raddr, af);
522 		}
523 
524 	get_addr:
525 		PF_ACPY(naddr, &rpool->counter, af);
526 		if (init_addr != NULL && PF_AZERO(init_addr, af))
527 			PF_ACPY(init_addr, naddr, af);
528 		PF_AINC(&rpool->counter, af);
529 		break;
530 	    }
531 	}
532 	if (*sn != NULL)
533 		PF_ACPY(&(*sn)->raddr, naddr, af);
534 
535 	mtx_unlock(&rpool->mtx);
536 
537 	if (V_pf_status.debug >= PF_DEBUG_NOISY &&
538 	    (rpool->opts & PF_POOL_TYPEMASK) != PF_POOL_NONE) {
539 		printf("pf_map_addr: selected address ");
540 		pf_print_host(naddr, 0, af);
541 		printf("\n");
542 	}
543 
544 	return (0);
545 }
546 
547 struct pf_krule *
548 pf_get_translation(struct pf_pdesc *pd, struct mbuf *m, int off, int direction,
549     struct pfi_kkif *kif, struct pf_ksrc_node **sn,
550     struct pf_state_key **skp, struct pf_state_key **nkp,
551     struct pf_addr *saddr, struct pf_addr *daddr,
552     uint16_t sport, uint16_t dport, struct pf_kanchor_stackframe *anchor_stack)
553 {
554 	struct pf_krule	*r = NULL;
555 	struct pf_addr	*naddr;
556 	uint16_t	*nport;
557 	uint16_t	 low, high;
558 
559 	PF_RULES_RASSERT();
560 	KASSERT(*skp == NULL, ("*skp not NULL"));
561 	KASSERT(*nkp == NULL, ("*nkp not NULL"));
562 
563 	if (direction == PF_OUT) {
564 		r = pf_match_translation(pd, m, off, direction, kif, saddr,
565 		    sport, daddr, dport, PF_RULESET_BINAT, anchor_stack);
566 		if (r == NULL)
567 			r = pf_match_translation(pd, m, off, direction, kif,
568 			    saddr, sport, daddr, dport, PF_RULESET_NAT,
569 			    anchor_stack);
570 	} else {
571 		r = pf_match_translation(pd, m, off, direction, kif, saddr,
572 		    sport, daddr, dport, PF_RULESET_RDR, anchor_stack);
573 		if (r == NULL)
574 			r = pf_match_translation(pd, m, off, direction, kif,
575 			    saddr, sport, daddr, dport, PF_RULESET_BINAT,
576 			    anchor_stack);
577 	}
578 
579 	if (r == NULL)
580 		return (NULL);
581 
582 	switch (r->action) {
583 	case PF_NONAT:
584 	case PF_NOBINAT:
585 	case PF_NORDR:
586 		return (NULL);
587 	}
588 
589 	*skp = pf_state_key_setup(pd, saddr, daddr, sport, dport);
590 	if (*skp == NULL)
591 		return (NULL);
592 	*nkp = pf_state_key_clone(*skp);
593 	if (*nkp == NULL) {
594 		uma_zfree(V_pf_state_key_z, *skp);
595 		*skp = NULL;
596 		return (NULL);
597 	}
598 
599 	/* XXX We only modify one side for now. */
600 	naddr = &(*nkp)->addr[1];
601 	nport = &(*nkp)->port[1];
602 
603 	switch (r->action) {
604 	case PF_NAT:
605 		if (pd->proto == IPPROTO_ICMP) {
606 			low  = 1;
607 			high = 65535;
608 		} else {
609 			low  = r->rpool.proxy_port[0];
610 			high = r->rpool.proxy_port[1];
611 		}
612 		if (r->rpool.mape.offset > 0) {
613 			if (pf_get_mape_sport(pd->af, pd->proto, r, saddr,
614 			    sport, daddr, dport, naddr, nport, sn)) {
615 				DPFPRINTF(PF_DEBUG_MISC,
616 				    ("pf: MAP-E port allocation (%u/%u/%u)"
617 				    " failed\n",
618 				    r->rpool.mape.offset,
619 				    r->rpool.mape.psidlen,
620 				    r->rpool.mape.psid));
621 				goto notrans;
622 			}
623 		} else if (pf_get_sport(pd->af, pd->proto, r, saddr, sport,
624 		    daddr, dport, naddr, nport, low, high, sn)) {
625 			DPFPRINTF(PF_DEBUG_MISC,
626 			    ("pf: NAT proxy port allocation (%u-%u) failed\n",
627 			    r->rpool.proxy_port[0], r->rpool.proxy_port[1]));
628 			goto notrans;
629 		}
630 		break;
631 	case PF_BINAT:
632 		switch (direction) {
633 		case PF_OUT:
634 			if (r->rpool.cur->addr.type == PF_ADDR_DYNIFTL){
635 				switch (pd->af) {
636 #ifdef INET
637 				case AF_INET:
638 					if (r->rpool.cur->addr.p.dyn->
639 					    pfid_acnt4 < 1)
640 						goto notrans;
641 					PF_POOLMASK(naddr,
642 					    &r->rpool.cur->addr.p.dyn->
643 					    pfid_addr4,
644 					    &r->rpool.cur->addr.p.dyn->
645 					    pfid_mask4, saddr, AF_INET);
646 					break;
647 #endif /* INET */
648 #ifdef INET6
649 				case AF_INET6:
650 					if (r->rpool.cur->addr.p.dyn->
651 					    pfid_acnt6 < 1)
652 						goto notrans;
653 					PF_POOLMASK(naddr,
654 					    &r->rpool.cur->addr.p.dyn->
655 					    pfid_addr6,
656 					    &r->rpool.cur->addr.p.dyn->
657 					    pfid_mask6, saddr, AF_INET6);
658 					break;
659 #endif /* INET6 */
660 				}
661 			} else
662 				PF_POOLMASK(naddr,
663 				    &r->rpool.cur->addr.v.a.addr,
664 				    &r->rpool.cur->addr.v.a.mask, saddr,
665 				    pd->af);
666 			break;
667 		case PF_IN:
668 			if (r->src.addr.type == PF_ADDR_DYNIFTL) {
669 				switch (pd->af) {
670 #ifdef INET
671 				case AF_INET:
672 					if (r->src.addr.p.dyn-> pfid_acnt4 < 1)
673 						goto notrans;
674 					PF_POOLMASK(naddr,
675 					    &r->src.addr.p.dyn->pfid_addr4,
676 					    &r->src.addr.p.dyn->pfid_mask4,
677 					    daddr, AF_INET);
678 					break;
679 #endif /* INET */
680 #ifdef INET6
681 				case AF_INET6:
682 					if (r->src.addr.p.dyn->pfid_acnt6 < 1)
683 						goto notrans;
684 					PF_POOLMASK(naddr,
685 					    &r->src.addr.p.dyn->pfid_addr6,
686 					    &r->src.addr.p.dyn->pfid_mask6,
687 					    daddr, AF_INET6);
688 					break;
689 #endif /* INET6 */
690 				}
691 			} else
692 				PF_POOLMASK(naddr, &r->src.addr.v.a.addr,
693 				    &r->src.addr.v.a.mask, daddr, pd->af);
694 			break;
695 		}
696 		break;
697 	case PF_RDR: {
698 		if (pf_map_addr(pd->af, r, saddr, naddr, NULL, sn))
699 			goto notrans;
700 		if ((r->rpool.opts & PF_POOL_TYPEMASK) == PF_POOL_BITMASK)
701 			PF_POOLMASK(naddr, naddr, &r->rpool.cur->addr.v.a.mask,
702 			    daddr, pd->af);
703 
704 		if (r->rpool.proxy_port[1]) {
705 			uint32_t	tmp_nport;
706 
707 			tmp_nport = ((ntohs(dport) - ntohs(r->dst.port[0])) %
708 			    (r->rpool.proxy_port[1] - r->rpool.proxy_port[0] +
709 			    1)) + r->rpool.proxy_port[0];
710 
711 			/* Wrap around if necessary. */
712 			if (tmp_nport > 65535)
713 				tmp_nport -= 65535;
714 			*nport = htons((uint16_t)tmp_nport);
715 		} else if (r->rpool.proxy_port[0])
716 			*nport = htons(r->rpool.proxy_port[0]);
717 		break;
718 	}
719 	default:
720 		panic("%s: unknown action %u", __func__, r->action);
721 	}
722 
723 	/* Return success only if translation really happened. */
724 	if (bcmp(*skp, *nkp, sizeof(struct pf_state_key_cmp)))
725 		return (r);
726 
727 notrans:
728 	uma_zfree(V_pf_state_key_z, *nkp);
729 	uma_zfree(V_pf_state_key_z, *skp);
730 	*skp = *nkp = NULL;
731 	*sn = NULL;
732 
733 	return (NULL);
734 }
735