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/ah_input.c,v 1.1.2.6 2002/04/28 05:40:26 suz Exp $ */ |
30 | /* $KAME: ah_input.c,v 1.67 2002/01/07 11:39:56 kjc 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 | * RFC1826/2402 authentication header. |
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/in_var.h> |
87 | #include <netinet/ip.h> |
88 | #include <netinet/ip_var.h> |
89 | #include <netinet/ip_ecn.h> |
90 | #include <netinet/in_pcb.h> |
91 | #if INET6 |
92 | #include <netinet6/ip6_ecn.h> |
93 | #endif |
94 | |
95 | #if INET6 |
96 | #include <netinet/ip6.h> |
97 | #include <netinet6/ip6_var.h> |
98 | #include <netinet6/in6_pcb.h> |
99 | #include <netinet/icmp6.h> |
100 | #include <netinet6/ip6protosw.h> |
101 | #endif |
102 | |
103 | #include <netinet6/ipsec.h> |
104 | #if INET6 |
105 | #include <netinet6/ipsec6.h> |
106 | #endif |
107 | #include <netinet6/ah.h> |
108 | #if INET6 |
109 | #include <netinet6/ah6.h> |
110 | #endif |
111 | #include <netkey/key.h> |
112 | #include <netkey/keydb.h> |
113 | #if IPSEC_DEBUG |
114 | #include <netkey/key_debug.h> |
115 | #else |
116 | #define KEYDEBUG(lev,arg) |
117 | #endif |
118 | |
119 | #include <net/kpi_protocol.h> |
120 | #include <netinet/kpi_ipfilter_var.h> |
121 | #include <mach/sdt.h> |
122 | |
123 | #include <net/net_osdep.h> |
124 | |
125 | #define IPLEN_FLIPPED |
126 | |
127 | #if INET |
128 | void |
129 | ah4_input(struct mbuf *m, int off) |
130 | { |
131 | struct ip *ip; |
132 | struct ah *ah; |
133 | u_int32_t spi; |
134 | const struct ah_algorithm *algo; |
135 | size_t siz; |
136 | size_t siz1; |
137 | u_char *cksum; |
138 | struct secasvar *sav = NULL; |
139 | u_int16_t nxt; |
140 | size_t hlen; |
141 | size_t stripsiz = 0; |
142 | sa_family_t ifamily; |
143 | |
144 | if (m->m_len < off + sizeof(struct newah)) { |
145 | m = m_pullup(m, off + sizeof(struct newah)); |
146 | if (!m) { |
147 | ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;" |
148 | "dropping the packet for simplicity\n" )); |
149 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
150 | goto fail; |
151 | } |
152 | } |
153 | |
154 | /* Expect 32-bit aligned data pointer on strict-align platforms */ |
155 | MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); |
156 | |
157 | ip = mtod(m, struct ip *); |
158 | ah = (struct ah *)(void *)(((caddr_t)ip) + off); |
159 | nxt = ah->ah_nxt; |
160 | #ifdef _IP_VHL |
161 | hlen = IP_VHL_HL(ip->ip_vhl) << 2; |
162 | #else |
163 | hlen = ip->ip_hl << 2; |
164 | #endif |
165 | |
166 | /* find the sassoc. */ |
167 | spi = ah->ah_spi; |
168 | |
169 | if ((sav = key_allocsa(AF_INET, |
170 | (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst, |
171 | IPPROTO_AH, spi)) == 0) { |
172 | ipseclog((LOG_WARNING, |
173 | "IPv4 AH input: no key association found for spi %u\n" , |
174 | (u_int32_t)ntohl(spi))); |
175 | IPSEC_STAT_INCREMENT(ipsecstat.in_nosa); |
176 | goto fail; |
177 | } |
178 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
179 | printf("DP ah4_input called to allocate SA:0x%llx\n" , |
180 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
181 | if (sav->state != SADB_SASTATE_MATURE |
182 | && sav->state != SADB_SASTATE_DYING) { |
183 | ipseclog((LOG_DEBUG, |
184 | "IPv4 AH input: non-mature/dying SA found for spi %u\n" , |
185 | (u_int32_t)ntohl(spi))); |
186 | IPSEC_STAT_INCREMENT(ipsecstat.in_badspi); |
187 | goto fail; |
188 | } |
189 | |
190 | algo = ah_algorithm_lookup(sav->alg_auth); |
191 | if (!algo) { |
192 | ipseclog((LOG_DEBUG, "IPv4 AH input: " |
193 | "unsupported authentication algorithm for spi %u\n" , |
194 | (u_int32_t)ntohl(spi))); |
195 | IPSEC_STAT_INCREMENT(ipsecstat.in_badspi); |
196 | goto fail; |
197 | } |
198 | |
199 | siz = (*algo->sumsiz)(sav); |
200 | siz1 = ((siz + 3) & ~(4 - 1)); |
201 | |
202 | /* |
203 | * sanity checks for header, 1. |
204 | */ |
205 | { |
206 | int sizoff; |
207 | |
208 | sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; |
209 | |
210 | /* |
211 | * Here, we do not do "siz1 == siz". This is because the way |
212 | * RFC240[34] section 2 is written. They do not require truncation |
213 | * to 96 bits. |
214 | * For example, Microsoft IPsec stack attaches 160 bits of |
215 | * authentication data for both hmac-md5 and hmac-sha1. For hmac-sha1, |
216 | * 32 bits of padding is attached. |
217 | * |
218 | * There are two downsides to this specification. |
219 | * They have no real harm, however, they leave us fuzzy feeling. |
220 | * - if we attach more than 96 bits of authentication data onto AH, |
221 | * we will never notice about possible modification by rogue |
222 | * intermediate nodes. |
223 | * Since extra bits in AH checksum is never used, this constitutes |
224 | * no real issue, however, it is wacky. |
225 | * - even if the peer attaches big authentication data, we will never |
226 | * notice the difference, since longer authentication data will just |
227 | * work. |
228 | * |
229 | * We may need some clarification in the spec. |
230 | */ |
231 | if (siz1 < siz) { |
232 | ipseclog((LOG_NOTICE, "sum length too short in IPv4 AH input " |
233 | "(%lu, should be at least %lu): %s\n" , |
234 | (u_int32_t)siz1, (u_int32_t)siz, |
235 | ipsec4_logpacketstr(ip, spi))); |
236 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
237 | goto fail; |
238 | } |
239 | if ((ah->ah_len << 2) - sizoff != siz1) { |
240 | ipseclog((LOG_NOTICE, "sum length mismatch in IPv4 AH input " |
241 | "(%d should be %lu): %s\n" , |
242 | (ah->ah_len << 2) - sizoff, (u_int32_t)siz1, |
243 | ipsec4_logpacketstr(ip, spi))); |
244 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
245 | goto fail; |
246 | } |
247 | |
248 | if (m->m_len < off + sizeof(struct ah) + sizoff + siz1) { |
249 | m = m_pullup(m, off + sizeof(struct ah) + sizoff + siz1); |
250 | if (!m) { |
251 | ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n" )); |
252 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
253 | goto fail; |
254 | } |
255 | /* Expect 32-bit aligned data ptr on strict-align platforms */ |
256 | MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); |
257 | |
258 | ip = mtod(m, struct ip *); |
259 | ah = (struct ah *)(void *)(((caddr_t)ip) + off); |
260 | } |
261 | } |
262 | |
263 | /* |
264 | * check for sequence number. |
265 | */ |
266 | if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { |
267 | if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav)) |
268 | ; /*okey*/ |
269 | else { |
270 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahreplay); |
271 | ipseclog((LOG_WARNING, |
272 | "replay packet in IPv4 AH input: %s %s\n" , |
273 | ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); |
274 | goto fail; |
275 | } |
276 | } |
277 | |
278 | /* |
279 | * alright, it seems sane. now we are going to check the |
280 | * cryptographic checksum. |
281 | */ |
282 | cksum = _MALLOC(siz1, M_TEMP, M_NOWAIT); |
283 | if (!cksum) { |
284 | ipseclog((LOG_DEBUG, "IPv4 AH input: " |
285 | "couldn't alloc temporary region for cksum\n" )); |
286 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
287 | goto fail; |
288 | } |
289 | |
290 | /* |
291 | * some of IP header fields are flipped to the host endian. |
292 | * convert them back to network endian. VERY stupid. |
293 | */ |
294 | ip->ip_len = htons(ip->ip_len + hlen); |
295 | ip->ip_off = htons(ip->ip_off); |
296 | if (ah4_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) { |
297 | FREE(cksum, M_TEMP); |
298 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
299 | goto fail; |
300 | } |
301 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahhist[sav->alg_auth]); |
302 | /* |
303 | * flip them back. |
304 | */ |
305 | ip->ip_len = ntohs(ip->ip_len) - hlen; |
306 | ip->ip_off = ntohs(ip->ip_off); |
307 | |
308 | { |
309 | caddr_t sumpos = NULL; |
310 | |
311 | if (sav->flags & SADB_X_EXT_OLD) { |
312 | /* RFC 1826 */ |
313 | sumpos = (caddr_t)(ah + 1); |
314 | } else { |
315 | /* RFC 2402 */ |
316 | sumpos = (caddr_t)(((struct newah *)ah) + 1); |
317 | } |
318 | |
319 | if (bcmp(sumpos, cksum, siz) != 0) { |
320 | ipseclog((LOG_WARNING, |
321 | "checksum mismatch in IPv4 AH input: %s %s\n" , |
322 | ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); |
323 | FREE(cksum, M_TEMP); |
324 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthfail); |
325 | goto fail; |
326 | } |
327 | } |
328 | |
329 | FREE(cksum, M_TEMP); |
330 | |
331 | m->m_flags |= M_AUTHIPHDR; |
332 | m->m_flags |= M_AUTHIPDGM; |
333 | |
334 | #if 0 |
335 | /* |
336 | * looks okey, but we need more sanity check. |
337 | * XXX should elaborate. |
338 | */ |
339 | if (ah->ah_nxt == IPPROTO_IPIP || ah->ah_nxt == IPPROTO_IP) { |
340 | struct ip *nip; |
341 | size_t sizoff; |
342 | |
343 | sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; |
344 | |
345 | if (m->m_len < off + sizeof(struct ah) + sizoff + siz1 + hlen) { |
346 | m = m_pullup(m, off + sizeof(struct ah) |
347 | + sizoff + siz1 + hlen); |
348 | if (!m) { |
349 | ipseclog((LOG_DEBUG, |
350 | "IPv4 AH input: can't pullup\n" )); |
351 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
352 | goto fail; |
353 | } |
354 | } |
355 | |
356 | nip = (struct ip *)((u_char *)(ah + 1) + sizoff + siz1); |
357 | if (nip->ip_src.s_addr != ip->ip_src.s_addr |
358 | || nip->ip_dst.s_addr != ip->ip_dst.s_addr) { |
359 | m->m_flags &= ~M_AUTHIPHDR; |
360 | m->m_flags &= ~M_AUTHIPDGM; |
361 | } |
362 | } |
363 | #if INET6 |
364 | else if (ah->ah_nxt == IPPROTO_IPV6) { |
365 | m->m_flags &= ~M_AUTHIPHDR; |
366 | m->m_flags &= ~M_AUTHIPDGM; |
367 | } |
368 | #endif /*INET6*/ |
369 | #endif /*0*/ |
370 | |
371 | if (m->m_flags & M_AUTHIPHDR |
372 | && m->m_flags & M_AUTHIPDGM) { |
373 | #if 0 |
374 | ipseclog((LOG_DEBUG, |
375 | "IPv4 AH input: authentication succeess\n" )); |
376 | #endif |
377 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthsucc); |
378 | } else { |
379 | ipseclog((LOG_WARNING, |
380 | "authentication failed in IPv4 AH input: %s %s\n" , |
381 | ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); |
382 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthfail); |
383 | goto fail; |
384 | } |
385 | |
386 | /* |
387 | * update sequence number. |
388 | */ |
389 | if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { |
390 | if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) { |
391 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahreplay); |
392 | goto fail; |
393 | } |
394 | } |
395 | |
396 | /* was it transmitted over the IPsec tunnel SA? */ |
397 | if (sav->flags & SADB_X_EXT_OLD) { |
398 | /* RFC 1826 */ |
399 | stripsiz = sizeof(struct ah) + siz1; |
400 | } else { |
401 | /* RFC 2402 */ |
402 | stripsiz = sizeof(struct newah) + siz1; |
403 | } |
404 | if (ipsec4_tunnel_validate(m, off + stripsiz, nxt, sav, &ifamily)) { |
405 | ifaddr_t ifa; |
406 | struct sockaddr_storage addr; |
407 | struct sockaddr_in *ipaddr; |
408 | |
409 | /* |
410 | * strip off all the headers that precedes AH. |
411 | * IP xx AH IP' payload -> IP' payload |
412 | * |
413 | * XXX more sanity checks |
414 | * XXX relationship with gif? |
415 | */ |
416 | u_int8_t tos, otos; |
417 | int sum; |
418 | |
419 | if (ifamily == AF_INET6) { |
420 | ipseclog((LOG_NOTICE, "ipsec tunnel protocol mismatch " |
421 | "in IPv4 AH input: %s\n" , ipsec_logsastr(sav))); |
422 | goto fail; |
423 | } |
424 | tos = ip->ip_tos; |
425 | m_adj(m, off + stripsiz); |
426 | if (m->m_len < sizeof(*ip)) { |
427 | m = m_pullup(m, sizeof(*ip)); |
428 | if (!m) { |
429 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
430 | goto fail; |
431 | } |
432 | } |
433 | ip = mtod(m, struct ip *); |
434 | otos = ip->ip_tos; |
435 | /* ECN consideration. */ |
436 | if (ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos) == 0) { |
437 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
438 | goto fail; |
439 | } |
440 | |
441 | if (otos != ip->ip_tos) { |
442 | sum = ~ntohs(ip->ip_sum) & 0xffff; |
443 | sum += (~otos & 0xffff) + ip->ip_tos; |
444 | sum = (sum >> 16) + (sum & 0xffff); |
445 | sum += (sum >> 16); /* add carry */ |
446 | ip->ip_sum = htons(~sum & 0xffff); |
447 | } |
448 | |
449 | if (!key_checktunnelsanity(sav, AF_INET, |
450 | (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) { |
451 | ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch " |
452 | "in IPv4 AH input: %s %s\n" , |
453 | ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); |
454 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
455 | goto fail; |
456 | } |
457 | |
458 | #if 1 |
459 | /* |
460 | * Should the inner packet be considered authentic? |
461 | * My current answer is: NO. |
462 | * |
463 | * host1 -- gw1 === gw2 -- host2 |
464 | * In this case, gw2 can trust the authenticity of the |
465 | * outer packet, but NOT inner. Packet may be altered |
466 | * between host1 and gw1. |
467 | * |
468 | * host1 -- gw1 === host2 |
469 | * This case falls into the same scenario as above. |
470 | * |
471 | * host1 === host2 |
472 | * This case is the only case when we may be able to leave |
473 | * M_AUTHIPHDR and M_AUTHIPDGM set. |
474 | * However, if host1 is wrongly configured, and allows |
475 | * attacker to inject some packet with src=host1 and |
476 | * dst=host2, you are in risk. |
477 | */ |
478 | m->m_flags &= ~M_AUTHIPHDR; |
479 | m->m_flags &= ~M_AUTHIPDGM; |
480 | #endif |
481 | |
482 | key_sa_recordxfer(sav, m); |
483 | if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 || |
484 | ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) { |
485 | IPSEC_STAT_INCREMENT(ipsecstat.in_nomem); |
486 | goto fail; |
487 | } |
488 | |
489 | bzero(&addr, sizeof(addr)); |
490 | ipaddr = (__typeof__(ipaddr))&addr; |
491 | ipaddr->sin_family = AF_INET; |
492 | ipaddr->sin_len = sizeof(*ipaddr); |
493 | ipaddr->sin_addr = ip->ip_dst; |
494 | |
495 | // update the receiving interface address based on the inner address |
496 | ifa = ifa_ifwithaddr((struct sockaddr *)&addr); |
497 | if (ifa) { |
498 | m->m_pkthdr.rcvif = ifa->ifa_ifp; |
499 | IFA_REMREF(ifa); |
500 | } |
501 | |
502 | // Input via IPSec interface |
503 | if (sav->sah->ipsec_if != NULL) { |
504 | if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) { |
505 | m = NULL; |
506 | goto done; |
507 | } else { |
508 | goto fail; |
509 | } |
510 | } |
511 | |
512 | if (proto_input(PF_INET, m) != 0) |
513 | goto fail; |
514 | nxt = IPPROTO_DONE; |
515 | } else { |
516 | /* |
517 | * strip off AH. |
518 | */ |
519 | |
520 | ip = mtod(m, struct ip *); |
521 | /* |
522 | * We do deep-copy since KAME requires that |
523 | * the packet is placed in a single external mbuf. |
524 | */ |
525 | ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off); |
526 | m->m_data += stripsiz; |
527 | m->m_len -= stripsiz; |
528 | m->m_pkthdr.len -= stripsiz; |
529 | |
530 | if (m->m_len < sizeof(*ip)) { |
531 | m = m_pullup(m, sizeof(*ip)); |
532 | if (m == NULL) { |
533 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
534 | goto fail; |
535 | } |
536 | } |
537 | ip = mtod(m, struct ip *); |
538 | #ifdef IPLEN_FLIPPED |
539 | ip->ip_len = ip->ip_len - stripsiz; |
540 | #else |
541 | ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz); |
542 | #endif |
543 | ip->ip_p = nxt; |
544 | /* forget about IP hdr checksum, the check has already been passed */ |
545 | |
546 | key_sa_recordxfer(sav, m); |
547 | if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) { |
548 | IPSEC_STAT_INCREMENT(ipsecstat.in_nomem); |
549 | goto fail; |
550 | } |
551 | |
552 | DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL, |
553 | struct ip *, ip, struct ifnet *, m->m_pkthdr.rcvif, |
554 | struct ip *, ip, struct ip6_hdr *, NULL); |
555 | |
556 | if (nxt != IPPROTO_DONE) { |
557 | // Input via IPSec interface |
558 | if (sav->sah->ipsec_if != NULL) { |
559 | ip->ip_len = htons(ip->ip_len + hlen); |
560 | ip->ip_off = htons(ip->ip_off); |
561 | ip->ip_sum = 0; |
562 | ip->ip_sum = ip_cksum_hdr_in(m, hlen); |
563 | if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) { |
564 | m = NULL; |
565 | goto done; |
566 | } else { |
567 | goto fail; |
568 | } |
569 | } |
570 | |
571 | if ((ip_protox[nxt]->pr_flags & PR_LASTHDR) != 0 && |
572 | ipsec4_in_reject(m, NULL)) { |
573 | IPSEC_STAT_INCREMENT(ipsecstat.in_polvio); |
574 | goto fail; |
575 | } |
576 | ip_proto_dispatch_in(m, off, nxt, 0); |
577 | } else |
578 | m_freem(m); |
579 | m = NULL; |
580 | } |
581 | done: |
582 | if (sav) { |
583 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
584 | printf("DP ah4_input call free SA:0x%llx\n" , |
585 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
586 | key_freesav(sav, KEY_SADB_UNLOCKED); |
587 | } |
588 | IPSEC_STAT_INCREMENT(ipsecstat.in_success); |
589 | return; |
590 | |
591 | fail: |
592 | if (sav) { |
593 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
594 | printf("DP ah4_input call free SA:0x%llx\n" , |
595 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
596 | key_freesav(sav, KEY_SADB_UNLOCKED); |
597 | } |
598 | if (m) |
599 | m_freem(m); |
600 | return; |
601 | } |
602 | #endif /* INET */ |
603 | |
604 | #if INET6 |
605 | int |
606 | ah6_input(struct mbuf **mp, int *offp, int proto) |
607 | { |
608 | #pragma unused(proto) |
609 | struct mbuf *m = *mp; |
610 | int off = *offp; |
611 | struct ip6_hdr *ip6; |
612 | struct ah *ah; |
613 | u_int32_t spi; |
614 | const struct ah_algorithm *algo; |
615 | size_t siz; |
616 | size_t siz1; |
617 | u_char *cksum; |
618 | struct secasvar *sav = NULL; |
619 | u_int16_t nxt; |
620 | size_t stripsiz = 0; |
621 | sa_family_t ifamily; |
622 | |
623 | IP6_EXTHDR_CHECK(m, off, sizeof(struct ah), {return IPPROTO_DONE;}); |
624 | ah = (struct ah *)(void *)(mtod(m, caddr_t) + off); |
625 | /* Expect 32-bit aligned data pointer on strict-align platforms */ |
626 | MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); |
627 | |
628 | ip6 = mtod(m, struct ip6_hdr *); |
629 | nxt = ah->ah_nxt; |
630 | |
631 | /* find the sassoc. */ |
632 | spi = ah->ah_spi; |
633 | |
634 | if (ntohs(ip6->ip6_plen) == 0) { |
635 | ipseclog((LOG_ERR, "IPv6 AH input: " |
636 | "AH with IPv6 jumbogram is not supported.\n" )); |
637 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
638 | goto fail; |
639 | } |
640 | |
641 | if ((sav = key_allocsa(AF_INET6, |
642 | (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst, |
643 | IPPROTO_AH, spi)) == 0) { |
644 | ipseclog((LOG_WARNING, |
645 | "IPv6 AH input: no key association found for spi %u\n" , |
646 | (u_int32_t)ntohl(spi))); |
647 | IPSEC_STAT_INCREMENT(ipsec6stat.in_nosa); |
648 | goto fail; |
649 | } |
650 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
651 | printf("DP ah6_input called to allocate SA:0x%llx\n" , |
652 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
653 | if (sav->state != SADB_SASTATE_MATURE |
654 | && sav->state != SADB_SASTATE_DYING) { |
655 | ipseclog((LOG_DEBUG, |
656 | "IPv6 AH input: non-mature/dying SA found for spi %u; " , |
657 | (u_int32_t)ntohl(spi))); |
658 | IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi); |
659 | goto fail; |
660 | } |
661 | |
662 | algo = ah_algorithm_lookup(sav->alg_auth); |
663 | if (!algo) { |
664 | ipseclog((LOG_DEBUG, "IPv6 AH input: " |
665 | "unsupported authentication algorithm for spi %u\n" , |
666 | (u_int32_t)ntohl(spi))); |
667 | IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi); |
668 | goto fail; |
669 | } |
670 | |
671 | siz = (*algo->sumsiz)(sav); |
672 | siz1 = ((siz + 3) & ~(4 - 1)); |
673 | |
674 | /* |
675 | * sanity checks for header, 1. |
676 | */ |
677 | { |
678 | int sizoff; |
679 | |
680 | sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; |
681 | |
682 | /* |
683 | * Here, we do not do "siz1 == siz". See ah4_input() for complete |
684 | * description. |
685 | */ |
686 | if (siz1 < siz) { |
687 | ipseclog((LOG_NOTICE, "sum length too short in IPv6 AH input " |
688 | "(%lu, should be at least %lu): %s\n" , |
689 | (u_int32_t)siz1, (u_int32_t)siz, |
690 | ipsec6_logpacketstr(ip6, spi))); |
691 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
692 | goto fail; |
693 | } |
694 | if ((ah->ah_len << 2) - sizoff != siz1) { |
695 | ipseclog((LOG_NOTICE, "sum length mismatch in IPv6 AH input " |
696 | "(%d should be %lu): %s\n" , |
697 | (ah->ah_len << 2) - sizoff, (u_int32_t)siz1, |
698 | ipsec6_logpacketstr(ip6, spi))); |
699 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
700 | goto fail; |
701 | } |
702 | IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1, |
703 | {return IPPROTO_DONE;}); |
704 | } |
705 | |
706 | /* |
707 | * check for sequence number. |
708 | */ |
709 | if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { |
710 | if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav)) |
711 | ; /*okey*/ |
712 | else { |
713 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahreplay); |
714 | ipseclog((LOG_WARNING, |
715 | "replay packet in IPv6 AH input: %s %s\n" , |
716 | ipsec6_logpacketstr(ip6, spi), |
717 | ipsec_logsastr(sav))); |
718 | goto fail; |
719 | } |
720 | } |
721 | |
722 | /* |
723 | * alright, it seems sane. now we are going to check the |
724 | * cryptographic checksum. |
725 | */ |
726 | cksum = _MALLOC(siz1, M_TEMP, M_NOWAIT); |
727 | if (!cksum) { |
728 | ipseclog((LOG_DEBUG, "IPv6 AH input: " |
729 | "couldn't alloc temporary region for cksum\n" )); |
730 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
731 | goto fail; |
732 | } |
733 | |
734 | if (ah6_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) { |
735 | FREE(cksum, M_TEMP); |
736 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
737 | goto fail; |
738 | } |
739 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahhist[sav->alg_auth]); |
740 | |
741 | { |
742 | caddr_t sumpos = NULL; |
743 | |
744 | if (sav->flags & SADB_X_EXT_OLD) { |
745 | /* RFC 1826 */ |
746 | sumpos = (caddr_t)(ah + 1); |
747 | } else { |
748 | /* RFC 2402 */ |
749 | sumpos = (caddr_t)(((struct newah *)ah) + 1); |
750 | } |
751 | |
752 | if (bcmp(sumpos, cksum, siz) != 0) { |
753 | ipseclog((LOG_WARNING, |
754 | "checksum mismatch in IPv6 AH input: %s %s\n" , |
755 | ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); |
756 | FREE(cksum, M_TEMP); |
757 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthfail); |
758 | goto fail; |
759 | } |
760 | } |
761 | |
762 | FREE(cksum, M_TEMP); |
763 | |
764 | m->m_flags |= M_AUTHIPHDR; |
765 | m->m_flags |= M_AUTHIPDGM; |
766 | |
767 | #if 0 |
768 | /* |
769 | * looks okey, but we need more sanity check. |
770 | * XXX should elaborate. |
771 | */ |
772 | if (ah->ah_nxt == IPPROTO_IPV6) { |
773 | struct ip6_hdr *nip6; |
774 | size_t sizoff; |
775 | |
776 | sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; |
777 | |
778 | IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1 |
779 | + sizeof(struct ip6_hdr), |
780 | {return IPPROTO_DONE;}); |
781 | |
782 | nip6 = (struct ip6_hdr *)((u_char *)(ah + 1) + sizoff + siz1); |
783 | if (!IN6_ARE_ADDR_EQUAL(&nip6->ip6_src, &ip6->ip6_src) |
784 | || !IN6_ARE_ADDR_EQUAL(&nip6->ip6_dst, &ip6->ip6_dst)) { |
785 | m->m_flags &= ~M_AUTHIPHDR; |
786 | m->m_flags &= ~M_AUTHIPDGM; |
787 | } |
788 | } else if (ah->ah_nxt == IPPROTO_IPIP) { |
789 | m->m_flags &= ~M_AUTHIPHDR; |
790 | m->m_flags &= ~M_AUTHIPDGM; |
791 | } else if (ah->ah_nxt == IPPROTO_IP) { |
792 | m->m_flags &= ~M_AUTHIPHDR; |
793 | m->m_flags &= ~M_AUTHIPDGM; |
794 | } |
795 | #endif |
796 | |
797 | if (m->m_flags & M_AUTHIPHDR |
798 | && m->m_flags & M_AUTHIPDGM) { |
799 | #if 0 |
800 | ipseclog((LOG_DEBUG, |
801 | "IPv6 AH input: authentication succeess\n" )); |
802 | #endif |
803 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthsucc); |
804 | } else { |
805 | ipseclog((LOG_WARNING, |
806 | "authentication failed in IPv6 AH input: %s %s\n" , |
807 | ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); |
808 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthfail); |
809 | goto fail; |
810 | } |
811 | |
812 | /* |
813 | * update sequence number. |
814 | */ |
815 | if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) { |
816 | if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) { |
817 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahreplay); |
818 | goto fail; |
819 | } |
820 | } |
821 | |
822 | /* was it transmitted over the IPsec tunnel SA? */ |
823 | if (sav->flags & SADB_X_EXT_OLD) { |
824 | /* RFC 1826 */ |
825 | stripsiz = sizeof(struct ah) + siz1; |
826 | } else { |
827 | /* RFC 2402 */ |
828 | stripsiz = sizeof(struct newah) + siz1; |
829 | } |
830 | if (ipsec6_tunnel_validate(m, off + stripsiz, nxt, sav, &ifamily)) { |
831 | ifaddr_t ifa; |
832 | struct sockaddr_storage addr; |
833 | struct sockaddr_in6 *ip6addr; |
834 | /* |
835 | * strip off all the headers that precedes AH. |
836 | * IP6 xx AH IP6' payload -> IP6' payload |
837 | * |
838 | * XXX more sanity checks |
839 | * XXX relationship with gif? |
840 | */ |
841 | u_int32_t flowinfo; /*net endian*/ |
842 | |
843 | if (ifamily == AF_INET) { |
844 | ipseclog((LOG_NOTICE, "ipsec tunnel protocol mismatch " |
845 | "in IPv6 AH input: %s\n" , ipsec_logsastr(sav))); |
846 | goto fail; |
847 | } |
848 | |
849 | flowinfo = ip6->ip6_flow; |
850 | m_adj(m, off + stripsiz); |
851 | if (m->m_len < sizeof(*ip6)) { |
852 | /* |
853 | * m_pullup is prohibited in KAME IPv6 input processing |
854 | * but there's no other way! |
855 | */ |
856 | m = m_pullup(m, sizeof(*ip6)); |
857 | if (!m) { |
858 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
859 | goto fail; |
860 | } |
861 | } |
862 | ip6 = mtod(m, struct ip6_hdr *); |
863 | /* ECN consideration. */ |
864 | if (ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow) == 0) { |
865 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
866 | goto fail; |
867 | } |
868 | if (!key_checktunnelsanity(sav, AF_INET6, |
869 | (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) { |
870 | ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch " |
871 | "in IPv6 AH input: %s %s\n" , |
872 | ipsec6_logpacketstr(ip6, spi), |
873 | ipsec_logsastr(sav))); |
874 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
875 | goto fail; |
876 | } |
877 | |
878 | #if 1 |
879 | /* |
880 | * should the inner packet be considered authentic? |
881 | * see comment in ah4_input(). |
882 | */ |
883 | m->m_flags &= ~M_AUTHIPHDR; |
884 | m->m_flags &= ~M_AUTHIPDGM; |
885 | #endif |
886 | |
887 | key_sa_recordxfer(sav, m); |
888 | if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 || |
889 | ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) { |
890 | IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem); |
891 | goto fail; |
892 | } |
893 | |
894 | bzero(&addr, sizeof(addr)); |
895 | ip6addr = (__typeof__(ip6addr))&addr; |
896 | ip6addr->sin6_family = AF_INET6; |
897 | ip6addr->sin6_len = sizeof(*ip6addr); |
898 | ip6addr->sin6_addr = ip6->ip6_dst; |
899 | |
900 | // update the receiving interface address based on the inner address |
901 | ifa = ifa_ifwithaddr((struct sockaddr *)&addr); |
902 | if (ifa) { |
903 | m->m_pkthdr.rcvif = ifa->ifa_ifp; |
904 | IFA_REMREF(ifa); |
905 | } |
906 | |
907 | // Input via IPSec interface |
908 | if (sav->sah->ipsec_if != NULL) { |
909 | if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) { |
910 | m = NULL; |
911 | nxt = IPPROTO_DONE; |
912 | goto done; |
913 | } else { |
914 | goto fail; |
915 | } |
916 | } |
917 | |
918 | if (proto_input(PF_INET6, m) != 0) |
919 | goto fail; |
920 | nxt = IPPROTO_DONE; |
921 | } else { |
922 | /* |
923 | * strip off AH. |
924 | */ |
925 | char *prvnxtp; |
926 | |
927 | /* |
928 | * Copy the value of the next header field of AH to the |
929 | * next header field of the previous header. |
930 | * This is necessary because AH will be stripped off below. |
931 | */ |
932 | prvnxtp = ip6_get_prevhdr(m, off); /* XXX */ |
933 | *prvnxtp = nxt; |
934 | |
935 | ip6 = mtod(m, struct ip6_hdr *); |
936 | /* |
937 | * We do deep-copy since KAME requires that |
938 | * the packet is placed in a single mbuf. |
939 | */ |
940 | ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off); |
941 | m->m_data += stripsiz; |
942 | m->m_len -= stripsiz; |
943 | m->m_pkthdr.len -= stripsiz; |
944 | ip6 = mtod(m, struct ip6_hdr *); |
945 | /* XXX jumbogram */ |
946 | ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz); |
947 | |
948 | key_sa_recordxfer(sav, m); |
949 | if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) { |
950 | IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem); |
951 | goto fail; |
952 | } |
953 | |
954 | // Input via IPSec interface |
955 | if (sav->sah->ipsec_if != NULL) { |
956 | if (ipsec_inject_inbound_packet(sav->sah->ipsec_if, m) == 0) { |
957 | m = NULL; |
958 | nxt = IPPROTO_DONE; |
959 | goto done; |
960 | } else { |
961 | goto fail; |
962 | } |
963 | } |
964 | } |
965 | |
966 | done: |
967 | *offp = off; |
968 | *mp = m; |
969 | if (sav) { |
970 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
971 | printf("DP ah6_input call free SA:0x%llx\n" , |
972 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
973 | key_freesav(sav, KEY_SADB_UNLOCKED); |
974 | } |
975 | IPSEC_STAT_INCREMENT(ipsec6stat.in_success); |
976 | return nxt; |
977 | |
978 | fail: |
979 | if (sav) { |
980 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
981 | printf("DP ah6_input call free SA:0x%llx\n" , |
982 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
983 | key_freesav(sav, KEY_SADB_UNLOCKED); |
984 | } |
985 | if (m) |
986 | m_freem(m); |
987 | return IPPROTO_DONE; |
988 | } |
989 | |
990 | void |
991 | ah6_ctlinput(int cmd, struct sockaddr *sa, void *d) |
992 | { |
993 | const struct newah *ahp; |
994 | struct newah ah; |
995 | struct secasvar *sav; |
996 | struct ip6_hdr *ip6; |
997 | struct mbuf *m; |
998 | struct ip6ctlparam *ip6cp = NULL; |
999 | int off = 0; |
1000 | struct sockaddr_in6 *sa6_src, *sa6_dst; |
1001 | |
1002 | if (sa->sa_family != AF_INET6 || |
1003 | sa->sa_len != sizeof(struct sockaddr_in6)) |
1004 | return; |
1005 | if ((unsigned)cmd >= PRC_NCMDS) |
1006 | return; |
1007 | |
1008 | /* if the parameter is from icmp6, decode it. */ |
1009 | if (d != NULL) { |
1010 | ip6cp = (struct ip6ctlparam *)d; |
1011 | m = ip6cp->ip6c_m; |
1012 | ip6 = ip6cp->ip6c_ip6; |
1013 | off = ip6cp->ip6c_off; |
1014 | } else { |
1015 | m = NULL; |
1016 | ip6 = NULL; |
1017 | } |
1018 | |
1019 | if (ip6) { |
1020 | /* |
1021 | * XXX: We assume that when ip6 is non NULL, |
1022 | * M and OFF are valid. |
1023 | */ |
1024 | |
1025 | /* check if we can safely examine src and dst ports */ |
1026 | if (m->m_pkthdr.len < off + sizeof(ah)) |
1027 | return; |
1028 | |
1029 | if (m->m_len < off + sizeof(ah)) { |
1030 | /* |
1031 | * this should be rare case, |
1032 | * so we compromise on this copy... |
1033 | */ |
1034 | m_copydata(m, off, sizeof(ah), (caddr_t)&ah); |
1035 | ahp = &ah; |
1036 | } else |
1037 | ahp = (struct newah *)(void *)(mtod(m, caddr_t) + off); |
1038 | |
1039 | if (cmd == PRC_MSGSIZE) { |
1040 | int valid = 0; |
1041 | |
1042 | /* |
1043 | * Check to see if we have a valid SA corresponding to |
1044 | * the address in the ICMP message payload. |
1045 | */ |
1046 | sa6_src = ip6cp->ip6c_src; |
1047 | sa6_dst = (struct sockaddr_in6 *)(void *)sa; |
1048 | sav = key_allocsa(AF_INET6, |
1049 | (caddr_t)&sa6_src->sin6_addr, |
1050 | (caddr_t)&sa6_dst->sin6_addr, |
1051 | IPPROTO_AH, ahp->ah_spi); |
1052 | if (sav) { |
1053 | if (sav->state == SADB_SASTATE_MATURE || |
1054 | sav->state == SADB_SASTATE_DYING) |
1055 | valid++; |
1056 | key_freesav(sav, KEY_SADB_UNLOCKED); |
1057 | } |
1058 | |
1059 | /* XXX Further validation? */ |
1060 | |
1061 | /* |
1062 | * Depending on the value of "valid" and routing table |
1063 | * size (mtudisc_{hi,lo}wat), we will: |
1064 | * - recalcurate the new MTU and create the |
1065 | * corresponding routing entry, or |
1066 | * - ignore the MTU change notification. |
1067 | */ |
1068 | icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); |
1069 | } |
1070 | |
1071 | /* we normally notify single pcb here */ |
1072 | } else { |
1073 | /* we normally notify any pcb here */ |
1074 | } |
1075 | } |
1076 | #endif /* INET6 */ |
1077 | |