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1 /*
2 * Copyright (c) 2008-2016 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29 /* $FreeBSD: src/sys/netinet6/esp_input.c,v 1.1.2.3 2001/07/03 11:01:50 ume Exp $ */
30 /* $KAME: esp_input.c,v 1.55 2001/03/23 08:08:47 itojun Exp $ */
31
32 /*
33 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
34 * All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 3. Neither the name of the project nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 */
60
61 /*
62 * RFC1827/2406 Encapsulated Security Payload.
63 */
64
65 #include <sys/param.h>
66 #include <sys/systm.h>
67 #include <sys/malloc.h>
68 #include <sys/mbuf.h>
69 #include <sys/mcache.h>
70 #include <sys/domain.h>
71 #include <sys/protosw.h>
72 #include <sys/socket.h>
73 #include <sys/errno.h>
74 #include <sys/time.h>
75 #include <sys/kernel.h>
76 #include <sys/syslog.h>
77
78 #include <net/if.h>
79 #include <net/if_ipsec.h>
80 #include <net/route.h>
81 #include <kern/cpu_number.h>
82 #include <kern/locks.h>
83
84 #include <netinet/in.h>
85 #include <netinet/in_systm.h>
86 #include <netinet/ip.h>
87 #include <netinet/ip_var.h>
88 #include <netinet/in_var.h>
89 #include <netinet/ip_ecn.h>
90 #include <netinet/in_pcb.h>
91 #include <netinet/udp.h>
92 #if INET6
93 #include <netinet6/ip6_ecn.h>
94 #endif
95
96 #if INET6
97 #include <netinet/ip6.h>
98 #include <netinet6/in6_pcb.h>
99 #include <netinet6/ip6_var.h>
100 #include <netinet/icmp6.h>
101 #include <netinet6/ip6protosw.h>
102 #endif
103
104 #include <netinet6/ipsec.h>
105 #if INET6
106 #include <netinet6/ipsec6.h>
107 #endif
108 #include <netinet6/ah.h>
109 #if INET6
110 #include <netinet6/ah6.h>
111 #endif
112 #include <netinet6/esp.h>
113 #if INET6
114 #include <netinet6/esp6.h>
115 #endif
116 #include <netkey/key.h>
117 #include <netkey/keydb.h>
118 #include <netkey/key_debug.h>
119
120 #include <net/kpi_protocol.h>
121 #include <netinet/kpi_ipfilter_var.h>
122
123 #include <net/net_osdep.h>
124 #include <mach/sdt.h>
125 #include <corecrypto/cc.h>
126
127 #include <sys/kdebug.h>
128 #define DBG_LAYER_BEG NETDBG_CODE(DBG_NETIPSEC, 1)
129 #define DBG_LAYER_END NETDBG_CODE(DBG_NETIPSEC, 3)
130 #define DBG_FNC_ESPIN NETDBG_CODE(DBG_NETIPSEC, (6 << 8))
131 #define DBG_FNC_DECRYPT NETDBG_CODE(DBG_NETIPSEC, (7 << 8))
132 #define IPLEN_FLIPPED
133
134 extern lck_mtx_t *sadb_mutex;
135
136 #if INET
137 #define ESPMAXLEN \
138 (sizeof(struct esp) < sizeof(struct newesp) \
139 ? sizeof(struct newesp) : sizeof(struct esp))
140
141 static struct ip *
142 esp4_input_strip_udp_encap(struct mbuf *m, int iphlen)
143 {
144 // strip the udp header that's encapsulating ESP
145 struct ip *ip;
146 size_t stripsiz = sizeof(struct udphdr);
147
148 ip = mtod(m, __typeof__(ip));
149 ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), iphlen);
150 m->m_data += stripsiz;
151 m->m_len -= stripsiz;
152 m->m_pkthdr.len -= stripsiz;
153 ip = mtod(m, __typeof__(ip));
154 ip->ip_len = ip->ip_len - stripsiz;
155 ip->ip_p = IPPROTO_ESP;
156 return ip;
157 }
158
159 static struct ip6_hdr *
160 esp6_input_strip_udp_encap(struct mbuf *m, int ip6hlen)
161 {
162 // strip the udp header that's encapsulating ESP
163 struct ip6_hdr *ip6;
164 size_t stripsiz = sizeof(struct udphdr);
165
166 ip6 = mtod(m, __typeof__(ip6));
167 ovbcopy((caddr_t)ip6, (caddr_t)(((u_char *)ip6) + stripsiz), ip6hlen);
168 m->m_data += stripsiz;
169 m->m_len -= stripsiz;
170 m->m_pkthdr.len -= stripsiz;
171 ip6 = mtod(m, __typeof__(ip6));
172 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz);
173 ip6->ip6_nxt = IPPROTO_ESP;
174 return ip6;
175 }
176
177 void
178 esp4_input(struct mbuf *m, int off)
179 {
180 (void)esp4_input_extended(m, off, NULL);
181 }
182
183 struct mbuf *
184 esp4_input_extended(struct mbuf *m, int off, ifnet_t interface)
185 {
186 struct ip *ip;
187 #if INET6
188 struct ip6_hdr *ip6;
189 #endif /* INET6 */
190 struct esp *esp;
191 struct esptail esptail;
192 u_int32_t spi;
193 u_int32_t seq;
194 struct secasvar *sav = NULL;
195 size_t taillen;
196 u_int16_t nxt;
197 const struct esp_algorithm *algo;
198 int ivlen;
199 size_t hlen;
200 size_t esplen;
201 sa_family_t ifamily;
202 struct mbuf *out_m = NULL;
203
204 KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_START, 0, 0, 0, 0, 0);
205 /* sanity check for alignment. */
206 if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) {
207 ipseclog((LOG_ERR, "IPv4 ESP input: packet alignment problem "
208 "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len));
209 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
210 goto bad;
211 }
212
213 if (m->m_len < off + ESPMAXLEN) {
214 m = m_pullup(m, off + ESPMAXLEN);
215 if (!m) {
216 ipseclog((LOG_DEBUG,
217 "IPv4 ESP input: can't pullup in esp4_input\n"));
218 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
219 goto bad;
220 }
221 }
222
223 m->m_pkthdr.csum_flags &= ~CSUM_RX_FLAGS;
224
225 /* Expect 32-bit aligned data pointer on strict-align platforms */
226 MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
227
228 ip = mtod(m, struct ip *);
229 // expect udp-encap and esp packets only
230 if (ip->ip_p != IPPROTO_ESP &&
231 !(ip->ip_p == IPPROTO_UDP && off >= sizeof(struct udphdr))) {
232 ipseclog((LOG_DEBUG,
233 "IPv4 ESP input: invalid protocol type\n"));
234 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
235 goto bad;
236 }
237 esp = (struct esp *)(void *)(((u_int8_t *)ip) + off);
238 #ifdef _IP_VHL
239 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
240 #else
241 hlen = ip->ip_hl << 2;
242 #endif
243
244 /* find the sassoc. */
245 spi = esp->esp_spi;
246
247 if ((sav = key_allocsa_extended(AF_INET,
248 (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst,
249 IPPROTO_ESP, spi, interface)) == 0) {
250 ipseclog((LOG_WARNING,
251 "IPv4 ESP input: no key association found for spi %u\n",
252 (u_int32_t)ntohl(spi)));
253 IPSEC_STAT_INCREMENT(ipsecstat.in_nosa);
254 goto bad;
255 }
256 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
257 printf("DP esp4_input called to allocate SA:0x%llx\n",
258 (uint64_t)VM_KERNEL_ADDRPERM(sav)));
259 if (sav->state != SADB_SASTATE_MATURE
260 && sav->state != SADB_SASTATE_DYING) {
261 ipseclog((LOG_DEBUG,
262 "IPv4 ESP input: non-mature/dying SA found for spi %u\n",
263 (u_int32_t)ntohl(spi)));
264 IPSEC_STAT_INCREMENT(ipsecstat.in_badspi);
265 goto bad;
266 }
267 algo = esp_algorithm_lookup(sav->alg_enc);
268 if (!algo) {
269 ipseclog((LOG_DEBUG, "IPv4 ESP input: "
270 "unsupported encryption algorithm for spi %u\n",
271 (u_int32_t)ntohl(spi)));
272 IPSEC_STAT_INCREMENT(ipsecstat.in_badspi);
273 goto bad;
274 }
275
276 /* check if we have proper ivlen information */
277 ivlen = sav->ivlen;
278 if (ivlen < 0) {
279 ipseclog((LOG_ERR, "inproper ivlen in IPv4 ESP input: %s %s\n",
280 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
281 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
282 goto bad;
283 }
284
285 seq = ntohl(((struct newesp *)esp)->esp_seq);
286
287 /* Save ICV from packet for verification later */
288 size_t siz = 0;
289 unsigned char saved_icv[AH_MAXSUMSIZE];
290 if (algo->finalizedecrypt) {
291 siz = algo->icvlen;
292 m_copydata(m, m->m_pkthdr.len - siz, siz, (caddr_t) saved_icv);
293 goto delay_icv;
294 }
295
296 if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay
297 && (sav->alg_auth && sav->key_auth))) {
298 goto noreplaycheck;
299 }
300
301 if (sav->alg_auth == SADB_X_AALG_NULL ||
302 sav->alg_auth == SADB_AALG_NONE) {
303 goto noreplaycheck;
304 }
305
306 /*
307 * check for sequence number.
308 */
309 if (ipsec_chkreplay(seq, sav)) {
310 ; /*okey*/
311 } else {
312 IPSEC_STAT_INCREMENT(ipsecstat.in_espreplay);
313 ipseclog((LOG_WARNING,
314 "replay packet in IPv4 ESP input: %s %s\n",
315 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
316 goto bad;
317 }
318
319 /* check ICV */
320 {
321 u_char sum0[AH_MAXSUMSIZE] __attribute__((aligned(4)));
322 u_char sum[AH_MAXSUMSIZE] __attribute__((aligned(4)));
323 const struct ah_algorithm *sumalgo;
324
325 sumalgo = ah_algorithm_lookup(sav->alg_auth);
326 if (!sumalgo) {
327 goto noreplaycheck;
328 }
329 siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1));
330 if (m->m_pkthdr.len < off + ESPMAXLEN + siz) {
331 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
332 goto bad;
333 }
334 if (AH_MAXSUMSIZE < siz) {
335 ipseclog((LOG_DEBUG,
336 "internal error: AH_MAXSUMSIZE must be larger than %lu\n",
337 (u_int32_t)siz));
338 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
339 goto bad;
340 }
341
342 m_copydata(m, m->m_pkthdr.len - siz, siz, (caddr_t) &sum0[0]);
343
344 if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) {
345 ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n",
346 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
347 IPSEC_STAT_INCREMENT(ipsecstat.in_espauthfail);
348 goto bad;
349 }
350
351 if (cc_cmp_safe(siz, sum0, sum)) {
352 ipseclog((LOG_WARNING, "cc_cmp fail in IPv4 ESP input: %s %s\n",
353 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
354 IPSEC_STAT_INCREMENT(ipsecstat.in_espauthfail);
355 goto bad;
356 }
357
358 delay_icv:
359
360 /* strip off the authentication data */
361 m_adj(m, -siz);
362 ip = mtod(m, struct ip *);
363 #ifdef IPLEN_FLIPPED
364 ip->ip_len = ip->ip_len - siz;
365 #else
366 ip->ip_len = htons(ntohs(ip->ip_len) - siz);
367 #endif
368 m->m_flags |= M_AUTHIPDGM;
369 IPSEC_STAT_INCREMENT(ipsecstat.in_espauthsucc);
370 }
371
372 /*
373 * update sequence number.
374 */
375 if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
376 if (ipsec_updatereplay(seq, sav)) {
377 IPSEC_STAT_INCREMENT(ipsecstat.in_espreplay);
378 goto bad;
379 }
380 }
381
382 noreplaycheck:
383
384 /* process main esp header. */
385 if (sav->flags & SADB_X_EXT_OLD) {
386 /* RFC 1827 */
387 esplen = sizeof(struct esp);
388 } else {
389 /* RFC 2406 */
390 if (sav->flags & SADB_X_EXT_DERIV) {
391 esplen = sizeof(struct esp);
392 } else {
393 esplen = sizeof(struct newesp);
394 }
395 }
396
397 if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) {
398 ipseclog((LOG_WARNING,
399 "IPv4 ESP input: packet too short\n"));
400 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
401 goto bad;
402 }
403
404 if (m->m_len < off + esplen + ivlen) {
405 m = m_pullup(m, off + esplen + ivlen);
406 if (!m) {
407 ipseclog((LOG_DEBUG,
408 "IPv4 ESP input: can't pullup in esp4_input\n"));
409 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
410 goto bad;
411 }
412 }
413
414 /*
415 * pre-compute and cache intermediate key
416 */
417 if (esp_schedule(algo, sav) != 0) {
418 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
419 goto bad;
420 }
421
422 /*
423 * decrypt the packet.
424 */
425 if (!algo->decrypt) {
426 panic("internal error: no decrypt function");
427 }
428 KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_START, 0, 0, 0, 0, 0);
429 if ((*algo->decrypt)(m, off, sav, algo, ivlen)) {
430 /* m is already freed */
431 m = NULL;
432 ipseclog((LOG_ERR, "decrypt fail in IPv4 ESP input: %s\n",
433 ipsec_logsastr(sav)));
434 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
435 KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 1, 0, 0, 0, 0);
436 goto bad;
437 }
438 KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 2, 0, 0, 0, 0);
439 IPSEC_STAT_INCREMENT(ipsecstat.in_esphist[sav->alg_enc]);
440
441 m->m_flags |= M_DECRYPTED;
442
443 if (algo->finalizedecrypt) {
444 if ((*algo->finalizedecrypt)(sav, saved_icv, algo->icvlen)) {
445 ipseclog((LOG_ERR, "packet decryption ICV failure\n"));
446 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
447 KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 1, 0, 0, 0, 0);
448 goto bad;
449 }
450 }
451
452 /*
453 * find the trailer of the ESP.
454 */
455 m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail),
456 (caddr_t)&esptail);
457 nxt = esptail.esp_nxt;
458 taillen = esptail.esp_padlen + sizeof(esptail);
459
460 if (m->m_pkthdr.len < taillen
461 || m->m_pkthdr.len - taillen < hlen) { /*?*/
462 ipseclog((LOG_WARNING,
463 "bad pad length in IPv4 ESP input: %s %s\n",
464 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
465 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
466 goto bad;
467 }
468
469 /* strip off the trailing pad area. */
470 m_adj(m, -taillen);
471 ip = mtod(m, struct ip *);
472 #ifdef IPLEN_FLIPPED
473 ip->ip_len = ip->ip_len - taillen;
474 #else
475 ip->ip_len = htons(ntohs(ip->ip_len) - taillen);
476 #endif
477 if (ip->ip_p == IPPROTO_UDP) {
478 // offset includes the outer ip and udp header lengths.
479 if (m->m_len < off) {
480 m = m_pullup(m, off);
481 if (!m) {
482 ipseclog((LOG_DEBUG,
483 "IPv4 ESP input: invalid udp encapsulated ESP packet length \n"));
484 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
485 goto bad;
486 }
487 }
488
489 // check the UDP encap header to detect changes in the source port, and then strip the header
490 off -= sizeof(struct udphdr); // off no longer includes the udphdr's size
491 // if peer is behind nat and this is the latest esp packet
492 if ((sav->flags & SADB_X_EXT_NATT_DETECTED_PEER) != 0 &&
493 (sav->flags & SADB_X_EXT_OLD) == 0 &&
494 seq && sav->replay &&
495 seq >= sav->replay->lastseq) {
496 struct udphdr *encap_uh = (__typeof__(encap_uh))(void *)((caddr_t)ip + off);
497 if (encap_uh->uh_sport &&
498 ntohs(encap_uh->uh_sport) != sav->remote_ike_port) {
499 sav->remote_ike_port = ntohs(encap_uh->uh_sport);
500 }
501 }
502 ip = esp4_input_strip_udp_encap(m, off);
503 esp = (struct esp *)(void *)(((u_int8_t *)ip) + off);
504 }
505
506 /* was it transmitted over the IPsec tunnel SA? */
507 if (ipsec4_tunnel_validate(m, off + esplen + ivlen, nxt, sav, &ifamily)) {
508 ifaddr_t ifa;
509 struct sockaddr_storage addr;
510
511 /*
512 * strip off all the headers that precedes ESP header.
513 * IP4 xx ESP IP4' payload -> IP4' payload
514 *
515 * XXX more sanity checks
516 * XXX relationship with gif?
517 */
518 u_int8_t tos, otos;
519 int sum;
520
521 tos = ip->ip_tos;
522 m_adj(m, off + esplen + ivlen);
523 if (ifamily == AF_INET) {
524 struct sockaddr_in *ipaddr;
525
526 if (m->m_len < sizeof(*ip)) {
527 m = m_pullup(m, sizeof(*ip));
528 if (!m) {
529 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
530 goto bad;
531 }
532 }
533 ip = mtod(m, struct ip *);
534 /* ECN consideration. */
535
536 otos = ip->ip_tos;
537 if (ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos) == 0) {
538 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
539 goto bad;
540 }
541
542 if (otos != ip->ip_tos) {
543 sum = ~ntohs(ip->ip_sum) & 0xffff;
544 sum += (~otos & 0xffff) + ip->ip_tos;
545 sum = (sum >> 16) + (sum & 0xffff);
546 sum += (sum >> 16); /* add carry */
547 ip->ip_sum = htons(~sum & 0xffff);
548 }
549
550 if (!key_checktunnelsanity(sav, AF_INET,
551 (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) {
552 ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
553 "in ESP input: %s %s\n",
554 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
555 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
556 goto bad;
557 }
558
559 bzero(&addr, sizeof(addr));
560 ipaddr = (__typeof__(ipaddr)) & addr;
561 ipaddr->sin_family = AF_INET;
562 ipaddr->sin_len = sizeof(*ipaddr);
563 ipaddr->sin_addr = ip->ip_dst;
564 #if INET6
565 } else if (ifamily == AF_INET6) {
566 struct sockaddr_in6 *ip6addr;
567
568 /*
569 * m_pullup is prohibited in KAME IPv6 input processing
570 * but there's no other way!
571 */
572 if (m->m_len < sizeof(*ip6)) {
573 m = m_pullup(m, sizeof(*ip6));
574 if (!m) {
575 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
576 goto bad;
577 }
578 }
579
580 /*
581 * Expect 32-bit aligned data pointer on strict-align
582 * platforms.
583 */
584 MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
585
586 ip6 = mtod(m, struct ip6_hdr *);
587
588 /* ECN consideration. */
589 if (ip64_ecn_egress(ip4_ipsec_ecn, &tos, &ip6->ip6_flow) == 0) {
590 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
591 goto bad;
592 }
593
594 if (!key_checktunnelsanity(sav, AF_INET6,
595 (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) {
596 ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
597 "in ESP input: %s %s\n",
598 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
599 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
600 goto bad;
601 }
602
603 bzero(&addr, sizeof(addr));
604 ip6addr = (__typeof__(ip6addr)) & addr;
605 ip6addr->sin6_family = AF_INET6;
606 ip6addr->sin6_len = sizeof(*ip6addr);
607 ip6addr->sin6_addr = ip6->ip6_dst;
608 #endif /* INET6 */
609 } else {
610 ipseclog((LOG_ERR, "ipsec tunnel unsupported address family "
611 "in ESP input\n"));
612 goto bad;
613 }
614
615 key_sa_recordxfer(sav, m);
616 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 ||
617 ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) {
618 IPSEC_STAT_INCREMENT(ipsecstat.in_nomem);
619 goto bad;
620 }
621
622 // update the receiving interface address based on the inner address
623 ifa = ifa_ifwithaddr((struct sockaddr *)&addr);
624 if (ifa) {
625 m->m_pkthdr.rcvif = ifa->ifa_ifp;
626 IFA_REMREF(ifa);
627 }
628
629 /* Clear the csum flags, they can't be valid for the inner headers */
630 m->m_pkthdr.csum_flags = 0;
631
632 // Input via IPSec interface
633 if (sav->sah->ipsec_if != NULL) {
634 // Return mbuf
635 if (interface != NULL &&
636 interface == sav->sah->ipsec_if) {
637 out_m = m;
638 goto done;
639 }
640
641 if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) {
642 m = NULL;
643 goto done;
644 } else {
645 goto bad;
646 }
647 }
648
649 if (proto_input(ifamily == AF_INET ? PF_INET : PF_INET6, m) != 0) {
650 goto bad;
651 }
652
653 nxt = IPPROTO_DONE;
654 KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 2, 0, 0, 0, 0);
655 } else {
656 /*
657 * strip off ESP header and IV.
658 * even in m_pulldown case, we need to strip off ESP so that
659 * we can always compute checksum for AH correctly.
660 */
661 size_t stripsiz;
662
663 stripsiz = esplen + ivlen;
664
665 ip = mtod(m, struct ip *);
666 ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off);
667 m->m_data += stripsiz;
668 m->m_len -= stripsiz;
669 m->m_pkthdr.len -= stripsiz;
670
671 ip = mtod(m, struct ip *);
672 #ifdef IPLEN_FLIPPED
673 ip->ip_len = ip->ip_len - stripsiz;
674 #else
675 ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz);
676 #endif
677 ip->ip_p = nxt;
678
679 key_sa_recordxfer(sav, m);
680 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) {
681 IPSEC_STAT_INCREMENT(ipsecstat.in_nomem);
682 goto bad;
683 }
684
685 /*
686 * Set the csum valid flag, if we authenticated the
687 * packet, the payload shouldn't be corrupt unless
688 * it was corrupted before being signed on the other
689 * side.
690 */
691 if (nxt == IPPROTO_TCP || nxt == IPPROTO_UDP) {
692 m->m_pkthdr.csum_flags = CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
693 m->m_pkthdr.csum_data = 0xFFFF;
694 _CASSERT(offsetof(struct pkthdr, csum_data) == offsetof(struct pkthdr, csum_rx_val));
695 }
696
697 if (nxt != IPPROTO_DONE) {
698 if ((ip_protox[nxt]->pr_flags & PR_LASTHDR) != 0 &&
699 ipsec4_in_reject(m, NULL)) {
700 IPSEC_STAT_INCREMENT(ipsecstat.in_polvio);
701 goto bad;
702 }
703 KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 3, 0, 0, 0, 0);
704
705 /* translate encapsulated UDP port ? */
706 if ((sav->flags & SADB_X_EXT_NATT_MULTIPLEUSERS) != 0) {
707 struct udphdr *udp;
708
709 if (nxt != IPPROTO_UDP) { /* not UPD packet - drop it */
710 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
711 goto bad;
712 }
713
714 if (m->m_len < off + sizeof(struct udphdr)) {
715 m = m_pullup(m, off + sizeof(struct udphdr));
716 if (!m) {
717 ipseclog((LOG_DEBUG,
718 "IPv4 ESP input: can't pullup UDP header in esp4_input\n"));
719 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
720 goto bad;
721 }
722 ip = mtod(m, struct ip *);
723 }
724 udp = (struct udphdr *)(void *)(((u_int8_t *)ip) + off);
725
726 lck_mtx_lock(sadb_mutex);
727 if (sav->natt_encapsulated_src_port == 0) {
728 sav->natt_encapsulated_src_port = udp->uh_sport;
729 } else if (sav->natt_encapsulated_src_port != udp->uh_sport) { /* something wrong */
730 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
731 lck_mtx_unlock(sadb_mutex);
732 goto bad;
733 }
734 lck_mtx_unlock(sadb_mutex);
735 udp->uh_sport = htons(sav->remote_ike_port);
736 udp->uh_sum = 0;
737 }
738
739 DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL,
740 struct ip *, ip, struct ifnet *, m->m_pkthdr.rcvif,
741 struct ip *, ip, struct ip6_hdr *, NULL);
742
743 // Input via IPsec interface legacy path
744 if (sav->sah->ipsec_if != NULL) {
745 int mlen;
746 if ((mlen = m_length2(m, NULL)) < hlen) {
747 ipseclog((LOG_DEBUG,
748 "IPv4 ESP input: decrypted packet too short %d < %d\n",
749 mlen, hlen));
750 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
751 goto bad;
752 }
753 ip->ip_len = htons(ip->ip_len + hlen);
754 ip->ip_off = htons(ip->ip_off);
755 ip->ip_sum = 0;
756 ip->ip_sum = ip_cksum_hdr_in(m, hlen);
757
758 // Return mbuf
759 if (interface != NULL &&
760 interface == sav->sah->ipsec_if) {
761 out_m = m;
762 goto done;
763 }
764
765 if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) {
766 m = NULL;
767 goto done;
768 } else {
769 goto bad;
770 }
771 }
772
773 ip_proto_dispatch_in(m, off, nxt, 0);
774 } else {
775 m_freem(m);
776 }
777 m = NULL;
778 }
779
780 done:
781 if (sav) {
782 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
783 printf("DP esp4_input call free SA:0x%llx\n",
784 (uint64_t)VM_KERNEL_ADDRPERM(sav)));
785 key_freesav(sav, KEY_SADB_UNLOCKED);
786 }
787 IPSEC_STAT_INCREMENT(ipsecstat.in_success);
788 return out_m;
789 bad:
790 if (sav) {
791 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
792 printf("DP esp4_input call free SA:0x%llx\n",
793 (uint64_t)VM_KERNEL_ADDRPERM(sav)));
794 key_freesav(sav, KEY_SADB_UNLOCKED);
795 }
796 if (m) {
797 m_freem(m);
798 }
799 KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 4, 0, 0, 0, 0);
800 return out_m;
801 }
802 #endif /* INET */
803
804 #if INET6
805
806 int
807 esp6_input(struct mbuf **mp, int *offp, int proto)
808 {
809 return esp6_input_extended(mp, offp, proto, NULL);
810 }
811
812 int
813 esp6_input_extended(struct mbuf **mp, int *offp, int proto, ifnet_t interface)
814 {
815 #pragma unused(proto)
816 struct mbuf *m = *mp;
817 int off = *offp;
818 struct ip *ip;
819 struct ip6_hdr *ip6;
820 struct esp *esp;
821 struct esptail esptail;
822 u_int32_t spi;
823 u_int32_t seq;
824 struct secasvar *sav = NULL;
825 size_t taillen;
826 u_int16_t nxt;
827 char *nproto;
828 const struct esp_algorithm *algo;
829 int ivlen;
830 size_t esplen;
831 sa_family_t ifamily;
832
833 /* sanity check for alignment. */
834 if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) {
835 ipseclog((LOG_ERR, "IPv6 ESP input: packet alignment problem "
836 "(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len));
837 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
838 goto bad;
839 }
840
841 #ifndef PULLDOWN_TEST
842 IP6_EXTHDR_CHECK(m, off, ESPMAXLEN, {return IPPROTO_DONE;});
843 esp = (struct esp *)(void *)(mtod(m, caddr_t) + off);
844 #else
845 IP6_EXTHDR_GET(esp, struct esp *, m, off, ESPMAXLEN);
846 if (esp == NULL) {
847 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
848 return IPPROTO_DONE;
849 }
850 #endif
851 m->m_pkthdr.csum_flags &= ~CSUM_RX_FLAGS;
852
853 /* Expect 32-bit data aligned pointer on strict-align platforms */
854 MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
855
856 ip6 = mtod(m, struct ip6_hdr *);
857
858 if (ntohs(ip6->ip6_plen) == 0) {
859 ipseclog((LOG_ERR, "IPv6 ESP input: "
860 "ESP with IPv6 jumbogram is not supported.\n"));
861 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
862 goto bad;
863 }
864
865 nproto = ip6_get_prevhdr(m, off);
866 if (nproto == NULL || (*nproto != IPPROTO_ESP &&
867 !(*nproto == IPPROTO_UDP && off >= sizeof(struct udphdr)))) {
868 ipseclog((LOG_DEBUG, "IPv6 ESP input: invalid protocol type\n"));
869 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
870 goto bad;
871 }
872
873 /* find the sassoc. */
874 spi = esp->esp_spi;
875
876 if ((sav = key_allocsa_extended(AF_INET6,
877 (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst,
878 IPPROTO_ESP, spi, interface)) == 0) {
879 ipseclog((LOG_WARNING,
880 "IPv6 ESP input: no key association found for spi %u\n",
881 (u_int32_t)ntohl(spi)));
882 IPSEC_STAT_INCREMENT(ipsec6stat.in_nosa);
883 goto bad;
884 }
885 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
886 printf("DP esp6_input called to allocate SA:0x%llx\n",
887 (uint64_t)VM_KERNEL_ADDRPERM(sav)));
888 if (sav->state != SADB_SASTATE_MATURE
889 && sav->state != SADB_SASTATE_DYING) {
890 ipseclog((LOG_DEBUG,
891 "IPv6 ESP input: non-mature/dying SA found for spi %u\n",
892 (u_int32_t)ntohl(spi)));
893 IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi);
894 goto bad;
895 }
896 algo = esp_algorithm_lookup(sav->alg_enc);
897 if (!algo) {
898 ipseclog((LOG_DEBUG, "IPv6 ESP input: "
899 "unsupported encryption algorithm for spi %u\n",
900 (u_int32_t)ntohl(spi)));
901 IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi);
902 goto bad;
903 }
904
905 /* check if we have proper ivlen information */
906 ivlen = sav->ivlen;
907 if (ivlen < 0) {
908 ipseclog((LOG_ERR, "inproper ivlen in IPv6 ESP input: %s %s\n",
909 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
910 IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi);
911 goto bad;
912 }
913
914 seq = ntohl(((struct newesp *)esp)->esp_seq);
915
916 /* Save ICV from packet for verification later */
917 size_t siz = 0;
918 unsigned char saved_icv[AH_MAXSUMSIZE];
919 if (algo->finalizedecrypt) {
920 siz = algo->icvlen;
921 m_copydata(m, m->m_pkthdr.len - siz, siz, (caddr_t) saved_icv);
922 goto delay_icv;
923 }
924
925 if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay
926 && (sav->alg_auth && sav->key_auth))) {
927 goto noreplaycheck;
928 }
929
930 if (sav->alg_auth == SADB_X_AALG_NULL ||
931 sav->alg_auth == SADB_AALG_NONE) {
932 goto noreplaycheck;
933 }
934
935 /*
936 * check for sequence number.
937 */
938 if (ipsec_chkreplay(seq, sav)) {
939 ; /*okey*/
940 } else {
941 IPSEC_STAT_INCREMENT(ipsec6stat.in_espreplay);
942 ipseclog((LOG_WARNING,
943 "replay packet in IPv6 ESP input: %s %s\n",
944 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
945 goto bad;
946 }
947
948 /* check ICV */
949 {
950 u_char sum0[AH_MAXSUMSIZE] __attribute__((aligned(4)));
951 u_char sum[AH_MAXSUMSIZE] __attribute__((aligned(4)));
952 const struct ah_algorithm *sumalgo;
953
954 sumalgo = ah_algorithm_lookup(sav->alg_auth);
955 if (!sumalgo) {
956 goto noreplaycheck;
957 }
958 siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1));
959 if (m->m_pkthdr.len < off + ESPMAXLEN + siz) {
960 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
961 goto bad;
962 }
963 if (AH_MAXSUMSIZE < siz) {
964 ipseclog((LOG_DEBUG,
965 "internal error: AH_MAXSUMSIZE must be larger than %lu\n",
966 (u_int32_t)siz));
967 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
968 goto bad;
969 }
970
971 m_copydata(m, m->m_pkthdr.len - siz, siz, (caddr_t) &sum0[0]);
972
973 if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) {
974 ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n",
975 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
976 IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthfail);
977 goto bad;
978 }
979
980 if (cc_cmp_safe(siz, sum0, sum)) {
981 ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n",
982 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
983 IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthfail);
984 goto bad;
985 }
986
987 delay_icv:
988
989 /* strip off the authentication data */
990 m_adj(m, -siz);
991 ip6 = mtod(m, struct ip6_hdr *);
992 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - siz);
993
994 m->m_flags |= M_AUTHIPDGM;
995 IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthsucc);
996 }
997
998 /*
999 * update sequence number.
1000 */
1001 if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
1002 if (ipsec_updatereplay(seq, sav)) {
1003 IPSEC_STAT_INCREMENT(ipsec6stat.in_espreplay);
1004 goto bad;
1005 }
1006 }
1007
1008 noreplaycheck:
1009
1010 /* process main esp header. */
1011 if (sav->flags & SADB_X_EXT_OLD) {
1012 /* RFC 1827 */
1013 esplen = sizeof(struct esp);
1014 } else {
1015 /* RFC 2406 */
1016 if (sav->flags & SADB_X_EXT_DERIV) {
1017 esplen = sizeof(struct esp);
1018 } else {
1019 esplen = sizeof(struct newesp);
1020 }
1021 }
1022
1023 if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) {
1024 ipseclog((LOG_WARNING,
1025 "IPv6 ESP input: packet too short\n"));
1026 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1027 goto bad;
1028 }
1029
1030 #ifndef PULLDOWN_TEST
1031 IP6_EXTHDR_CHECK(m, off, esplen + ivlen, return IPPROTO_DONE); /*XXX*/
1032 #else
1033 IP6_EXTHDR_GET(esp, struct esp *, m, off, esplen + ivlen);
1034 if (esp == NULL) {
1035 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1036 m = NULL;
1037 goto bad;
1038 }
1039 #endif
1040 ip6 = mtod(m, struct ip6_hdr *); /*set it again just in case*/
1041
1042 /*
1043 * pre-compute and cache intermediate key
1044 */
1045 if (esp_schedule(algo, sav) != 0) {
1046 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1047 goto bad;
1048 }
1049
1050 /*
1051 * decrypt the packet.
1052 */
1053 if (!algo->decrypt) {
1054 panic("internal error: no decrypt function");
1055 }
1056 if ((*algo->decrypt)(m, off, sav, algo, ivlen)) {
1057 /* m is already freed */
1058 m = NULL;
1059 ipseclog((LOG_ERR, "decrypt fail in IPv6 ESP input: %s\n",
1060 ipsec_logsastr(sav)));
1061 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1062 goto bad;
1063 }
1064 IPSEC_STAT_INCREMENT(ipsec6stat.in_esphist[sav->alg_enc]);
1065
1066 m->m_flags |= M_DECRYPTED;
1067
1068 if (algo->finalizedecrypt) {
1069 if ((*algo->finalizedecrypt)(sav, saved_icv, algo->icvlen)) {
1070 ipseclog((LOG_ERR, "packet decryption ICV failure\n"));
1071 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
1072 KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 1, 0, 0, 0, 0);
1073 goto bad;
1074 }
1075 }
1076
1077 /*
1078 * find the trailer of the ESP.
1079 */
1080 m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail),
1081 (caddr_t)&esptail);
1082 nxt = esptail.esp_nxt;
1083 taillen = esptail.esp_padlen + sizeof(esptail);
1084
1085 if (m->m_pkthdr.len < taillen
1086 || m->m_pkthdr.len - taillen < sizeof(struct ip6_hdr)) { /*?*/
1087 ipseclog((LOG_WARNING,
1088 "bad pad length in IPv6 ESP input: %s %s\n",
1089 ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
1090 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1091 goto bad;
1092 }
1093
1094 /* strip off the trailing pad area. */
1095 m_adj(m, -taillen);
1096 ip6 = mtod(m, struct ip6_hdr *);
1097 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - taillen);
1098
1099 if (*nproto == IPPROTO_UDP) {
1100 // offset includes the outer ip and udp header lengths.
1101 if (m->m_len < off) {
1102 m = m_pullup(m, off);
1103 if (!m) {
1104 ipseclog((LOG_DEBUG,
1105 "IPv6 ESP input: invalid udp encapsulated ESP packet length\n"));
1106 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1107 goto bad;
1108 }
1109 }
1110
1111 // check the UDP encap header to detect changes in the source port, and then strip the header
1112 off -= sizeof(struct udphdr); // off no longer includes the udphdr's size
1113 // if peer is behind nat and this is the latest esp packet
1114 if ((sav->flags & SADB_X_EXT_NATT_DETECTED_PEER) != 0 &&
1115 (sav->flags & SADB_X_EXT_OLD) == 0 &&
1116 seq && sav->replay &&
1117 seq >= sav->replay->lastseq) {
1118 struct udphdr *encap_uh = (__typeof__(encap_uh))(void *)((caddr_t)ip6 + off);
1119 if (encap_uh->uh_sport &&
1120 ntohs(encap_uh->uh_sport) != sav->remote_ike_port) {
1121 sav->remote_ike_port = ntohs(encap_uh->uh_sport);
1122 }
1123 }
1124 ip6 = esp6_input_strip_udp_encap(m, off);
1125 esp = (struct esp *)(void *)(((u_int8_t *)ip6) + off);
1126 }
1127
1128
1129 /* was it transmitted over the IPsec tunnel SA? */
1130 if (ipsec6_tunnel_validate(m, off + esplen + ivlen, nxt, sav, &ifamily)) {
1131 ifaddr_t ifa;
1132 struct sockaddr_storage addr;
1133
1134 /*
1135 * strip off all the headers that precedes ESP header.
1136 * IP6 xx ESP IP6' payload -> IP6' payload
1137 *
1138 * XXX more sanity checks
1139 * XXX relationship with gif?
1140 */
1141 u_int32_t flowinfo; /*net endian*/
1142 flowinfo = ip6->ip6_flow;
1143 m_adj(m, off + esplen + ivlen);
1144 if (ifamily == AF_INET6) {
1145 struct sockaddr_in6 *ip6addr;
1146
1147 if (m->m_len < sizeof(*ip6)) {
1148 #ifndef PULLDOWN_TEST
1149 /*
1150 * m_pullup is prohibited in KAME IPv6 input processing
1151 * but there's no other way!
1152 */
1153 #else
1154 /* okay to pullup in m_pulldown style */
1155 #endif
1156 m = m_pullup(m, sizeof(*ip6));
1157 if (!m) {
1158 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1159 goto bad;
1160 }
1161 }
1162 ip6 = mtod(m, struct ip6_hdr *);
1163 /* ECN consideration. */
1164 if (ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow) == 0) {
1165 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1166 goto bad;
1167 }
1168 if (!key_checktunnelsanity(sav, AF_INET6,
1169 (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) {
1170 ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
1171 "in IPv6 ESP input: %s %s\n",
1172 ipsec6_logpacketstr(ip6, spi),
1173 ipsec_logsastr(sav)));
1174 IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
1175 goto bad;
1176 }
1177
1178 bzero(&addr, sizeof(addr));
1179 ip6addr = (__typeof__(ip6addr)) & addr;
1180 ip6addr->sin6_family = AF_INET6;
1181 ip6addr->sin6_len = sizeof(*ip6addr);
1182 ip6addr->sin6_addr = ip6->ip6_dst;
1183 } else if (ifamily == AF_INET) {
1184 struct sockaddr_in *ipaddr;
1185
1186 if (m->m_len < sizeof(*ip)) {
1187 m = m_pullup(m, sizeof(*ip));
1188 if (!m) {
1189 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
1190 goto bad;
1191 }
1192 }
1193
1194 u_int8_t otos;
1195 int sum;
1196
1197 ip = mtod(m, struct ip *);
1198 otos = ip->ip_tos;
1199 /* ECN consideration. */
1200 if (ip46_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip->ip_tos) == 0) {
1201 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
1202 goto bad;
1203 }
1204
1205 if (otos != ip->ip_tos) {
1206 sum = ~ntohs(ip->ip_sum) & 0xffff;
1207 sum += (~otos & 0xffff) + ip->ip_tos;
1208 sum = (sum >> 16) + (sum & 0xffff);
1209 sum += (sum >> 16); /* add carry */
1210 ip->ip_sum = htons(~sum & 0xffff);
1211 }
1212
1213 if (!key_checktunnelsanity(sav, AF_INET,
1214 (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) {
1215 ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
1216 "in ESP input: %s %s\n",
1217 ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
1218 IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
1219 goto bad;
1220 }
1221
1222 bzero(&addr, sizeof(addr));
1223 ipaddr = (__typeof__(ipaddr)) & addr;
1224 ipaddr->sin_family = AF_INET;
1225 ipaddr->sin_len = sizeof(*ipaddr);
1226 ipaddr->sin_addr = ip->ip_dst;
1227 }
1228
1229 key_sa_recordxfer(sav, m);
1230 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 ||
1231 ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) {
1232 IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem);
1233 goto bad;
1234 }
1235
1236 // update the receiving interface address based on the inner address
1237 ifa = ifa_ifwithaddr((struct sockaddr *)&addr);
1238 if (ifa) {
1239 m->m_pkthdr.rcvif = ifa->ifa_ifp;
1240 IFA_REMREF(ifa);
1241 }
1242
1243 // Input via IPSec interface
1244 if (sav->sah->ipsec_if != NULL) {
1245 // Return mbuf
1246 if (interface != NULL &&
1247 interface == sav->sah->ipsec_if) {
1248 goto done;
1249 }
1250
1251 if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) {
1252 m = NULL;
1253 nxt = IPPROTO_DONE;
1254 goto done;
1255 } else {
1256 goto bad;
1257 }
1258 }
1259
1260 if (proto_input(ifamily == AF_INET ? PF_INET : PF_INET6, m) != 0) {
1261 goto bad;
1262 }
1263 nxt = IPPROTO_DONE;
1264 } else {
1265 /*
1266 * strip off ESP header and IV.
1267 * even in m_pulldown case, we need to strip off ESP so that
1268 * we can always compute checksum for AH correctly.
1269 */
1270 size_t stripsiz;
1271 char *prvnxtp;
1272
1273 /*
1274 * Set the next header field of the previous header correctly.
1275 */
1276 prvnxtp = ip6_get_prevhdr(m, off); /* XXX */
1277 *prvnxtp = nxt;
1278
1279 stripsiz = esplen + ivlen;
1280
1281 ip6 = mtod(m, struct ip6_hdr *);
1282 if (m->m_len >= stripsiz + off) {
1283 ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off);
1284 m->m_data += stripsiz;
1285 m->m_len -= stripsiz;
1286 m->m_pkthdr.len -= stripsiz;
1287 } else {
1288 /*
1289 * this comes with no copy if the boundary is on
1290 * cluster
1291 */
1292 struct mbuf *n;
1293
1294 n = m_split(m, off, M_DONTWAIT);
1295 if (n == NULL) {
1296 /* m is retained by m_split */
1297 goto bad;
1298 }
1299 m_adj(n, stripsiz);
1300 /* m_cat does not update m_pkthdr.len */
1301 m->m_pkthdr.len += n->m_pkthdr.len;
1302 m_cat(m, n);
1303 }
1304
1305 #ifndef PULLDOWN_TEST
1306 /*
1307 * KAME requires that the packet to be contiguous on the
1308 * mbuf. We need to make that sure.
1309 * this kind of code should be avoided.
1310 * XXX other conditions to avoid running this part?
1311 */
1312 if (m->m_len != m->m_pkthdr.len) {
1313 struct mbuf *n = NULL;
1314 int maxlen;
1315
1316 MGETHDR(n, M_DONTWAIT, MT_HEADER); /* MAC-OK */
1317 maxlen = MHLEN;
1318 if (n) {
1319 M_COPY_PKTHDR(n, m);
1320 }
1321 if (n && m->m_pkthdr.len > maxlen) {
1322 MCLGET(n, M_DONTWAIT);
1323 maxlen = MCLBYTES;
1324 if ((n->m_flags & M_EXT) == 0) {
1325 m_free(n);
1326 n = NULL;
1327 }
1328 }
1329 if (!n) {
1330 printf("esp6_input: mbuf allocation failed\n");
1331 goto bad;
1332 }
1333
1334 if (m->m_pkthdr.len <= maxlen) {
1335 m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t));
1336 n->m_len = m->m_pkthdr.len;
1337 n->m_pkthdr.len = m->m_pkthdr.len;
1338 n->m_next = NULL;
1339 m_freem(m);
1340 } else {
1341 m_copydata(m, 0, maxlen, mtod(n, caddr_t));
1342 n->m_len = maxlen;
1343 n->m_pkthdr.len = m->m_pkthdr.len;
1344 n->m_next = m;
1345 m_adj(m, maxlen);
1346 m->m_flags &= ~M_PKTHDR;
1347 }
1348 m = n;
1349 }
1350 #endif
1351
1352 ip6 = mtod(m, struct ip6_hdr *);
1353 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz);
1354
1355 key_sa_recordxfer(sav, m);
1356 if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) {
1357 IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem);
1358 goto bad;
1359 }
1360
1361 /*
1362 * Set the csum valid flag, if we authenticated the
1363 * packet, the payload shouldn't be corrupt unless
1364 * it was corrupted before being signed on the other
1365 * side.
1366 */
1367 if (nxt == IPPROTO_TCP || nxt == IPPROTO_UDP) {
1368 m->m_pkthdr.csum_flags = CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
1369 m->m_pkthdr.csum_data = 0xFFFF;
1370 _CASSERT(offsetof(struct pkthdr, csum_data) == offsetof(struct pkthdr, csum_rx_val));
1371 }
1372
1373 // Input via IPSec interface
1374 if (sav->sah->ipsec_if != NULL) {
1375 // Return mbuf
1376 if (interface != NULL &&
1377 interface == sav->sah->ipsec_if) {
1378 goto done;
1379 }
1380
1381 if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) {
1382 m = NULL;
1383 nxt = IPPROTO_DONE;
1384 goto done;
1385 } else {
1386 goto bad;
1387 }
1388 }
1389 }
1390
1391 done:
1392 *offp = off;
1393 *mp = m;
1394 if (sav) {
1395 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1396 printf("DP esp6_input call free SA:0x%llx\n",
1397 (uint64_t)VM_KERNEL_ADDRPERM(sav)));
1398 key_freesav(sav, KEY_SADB_UNLOCKED);
1399 }
1400 IPSEC_STAT_INCREMENT(ipsec6stat.in_success);
1401 return nxt;
1402
1403 bad:
1404 if (sav) {
1405 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
1406 printf("DP esp6_input call free SA:0x%llx\n",
1407 (uint64_t)VM_KERNEL_ADDRPERM(sav)));
1408 key_freesav(sav, KEY_SADB_UNLOCKED);
1409 }
1410 if (m) {
1411 m_freem(m);
1412 }
1413 if (interface != NULL) {
1414 *mp = NULL;
1415 }
1416 return IPPROTO_DONE;
1417 }
1418
1419 void
1420 esp6_ctlinput(int cmd, struct sockaddr *sa, void *d, __unused struct ifnet *ifp)
1421 {
1422 const struct newesp *espp;
1423 struct newesp esp;
1424 struct ip6ctlparam *ip6cp = NULL, ip6cp1;
1425 struct secasvar *sav;
1426 struct ip6_hdr *ip6;
1427 struct mbuf *m;
1428 int off = 0;
1429 struct sockaddr_in6 *sa6_src, *sa6_dst;
1430
1431 if (sa->sa_family != AF_INET6 ||
1432 sa->sa_len != sizeof(struct sockaddr_in6)) {
1433 return;
1434 }
1435 if ((unsigned)cmd >= PRC_NCMDS) {
1436 return;
1437 }
1438
1439 /* if the parameter is from icmp6, decode it. */
1440 if (d != NULL) {
1441 ip6cp = (struct ip6ctlparam *)d;
1442 m = ip6cp->ip6c_m;
1443 ip6 = ip6cp->ip6c_ip6;
1444 off = ip6cp->ip6c_off;
1445 } else {
1446 m = NULL;
1447 ip6 = NULL;
1448 }
1449
1450 if (ip6) {
1451 /*
1452 * Notify the error to all possible sockets via pfctlinput2.
1453 * Since the upper layer information (such as protocol type,
1454 * source and destination ports) is embedded in the encrypted
1455 * data and might have been cut, we can't directly call
1456 * an upper layer ctlinput function. However, the pcbnotify
1457 * function will consider source and destination addresses
1458 * as well as the flow info value, and may be able to find
1459 * some PCB that should be notified.
1460 * Although pfctlinput2 will call esp6_ctlinput(), there is
1461 * no possibility of an infinite loop of function calls,
1462 * because we don't pass the inner IPv6 header.
1463 */
1464 bzero(&ip6cp1, sizeof(ip6cp1));
1465 ip6cp1.ip6c_src = ip6cp->ip6c_src;
1466 pfctlinput2(cmd, sa, (void *)&ip6cp1);
1467
1468 /*
1469 * Then go to special cases that need ESP header information.
1470 * XXX: We assume that when ip6 is non NULL,
1471 * M and OFF are valid.
1472 */
1473
1474 /* check if we can safely examine src and dst ports */
1475 if (m->m_pkthdr.len < off + sizeof(esp)) {
1476 return;
1477 }
1478
1479 if (m->m_len < off + sizeof(esp)) {
1480 /*
1481 * this should be rare case,
1482 * so we compromise on this copy...
1483 */
1484 m_copydata(m, off, sizeof(esp), (caddr_t)&esp);
1485 espp = &esp;
1486 } else {
1487 espp = (struct newesp*)(void *)(mtod(m, caddr_t) + off);
1488 }
1489
1490 if (cmd == PRC_MSGSIZE) {
1491 int valid = 0;
1492
1493 /*
1494 * Check to see if we have a valid SA corresponding to
1495 * the address in the ICMP message payload.
1496 */
1497 sa6_src = ip6cp->ip6c_src;
1498 sa6_dst = (struct sockaddr_in6 *)(void *)sa;
1499 sav = key_allocsa(AF_INET6,
1500 (caddr_t)&sa6_src->sin6_addr,
1501 (caddr_t)&sa6_dst->sin6_addr,
1502 IPPROTO_ESP, espp->esp_spi);
1503 if (sav) {
1504 if (sav->state == SADB_SASTATE_MATURE ||
1505 sav->state == SADB_SASTATE_DYING) {
1506 valid++;
1507 }
1508 key_freesav(sav, KEY_SADB_UNLOCKED);
1509 }
1510
1511 /* XXX Further validation? */
1512
1513 /*
1514 * Depending on the value of "valid" and routing table
1515 * size (mtudisc_{hi,lo}wat), we will:
1516 * - recalcurate the new MTU and create the
1517 * corresponding routing entry, or
1518 * - ignore the MTU change notification.
1519 */
1520 icmp6_mtudisc_update((struct ip6ctlparam *)d, valid);
1521 }
1522 } else {
1523 /* we normally notify any pcb here */
1524 }
1525 }
1526 #endif /* INET6 */
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