1 | /* |
2 | * Copyright (c) 2008-2023 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 | #include <netinet6/ip6_ecn.h> |
92 | |
93 | #include <netinet/ip6.h> |
94 | #include <netinet6/ip6_var.h> |
95 | #include <netinet6/in6_pcb.h> |
96 | #include <netinet/icmp6.h> |
97 | #include <netinet6/ip6protosw.h> |
98 | |
99 | #include <netinet6/ipsec.h> |
100 | #include <netinet6/ipsec6.h> |
101 | #include <netinet6/ah.h> |
102 | #include <netinet6/ah6.h> |
103 | #include <netkey/key.h> |
104 | #include <netkey/keydb.h> |
105 | #if IPSEC_DEBUG |
106 | #include <netkey/key_debug.h> |
107 | #else |
108 | #define KEYDEBUG(lev, arg) |
109 | #endif |
110 | |
111 | #include <net/kpi_protocol.h> |
112 | #include <netinet/kpi_ipfilter_var.h> |
113 | #include <mach/sdt.h> |
114 | |
115 | #include <net/net_osdep.h> |
116 | |
117 | #define IPLEN_FLIPPED |
118 | |
119 | #if INET |
120 | void |
121 | ah4_input(struct mbuf *m, int off) |
122 | { |
123 | struct ip *ip; |
124 | struct ah *ah; |
125 | u_int32_t spi; |
126 | const struct ah_algorithm *algo; |
127 | size_t siz; |
128 | size_t siz1; |
129 | u_char *cksum; |
130 | struct secasvar *sav = NULL; |
131 | u_int16_t nxt; |
132 | u_int8_t hlen; |
133 | size_t stripsiz = 0; |
134 | sa_family_t ifamily; |
135 | |
136 | if (m->m_len < off + sizeof(struct newah)) { |
137 | m = m_pullup(m, off + sizeof(struct newah)); |
138 | if (!m) { |
139 | ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;" |
140 | "dropping the packet for simplicity\n" )); |
141 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
142 | goto fail; |
143 | } |
144 | } |
145 | |
146 | /* Expect 32-bit aligned data pointer on strict-align platforms */ |
147 | MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); |
148 | |
149 | ip = mtod(m, struct ip *); |
150 | ah = (struct ah *)(void *)(((caddr_t)ip) + off); |
151 | nxt = ah->ah_nxt; |
152 | #ifdef _IP_VHL |
153 | hlen = (u_int8_t)(IP_VHL_HL(ip->ip_vhl) << 2); |
154 | #else |
155 | hlen = (u_int8_t)(ip->ip_hl << 2); |
156 | #endif |
157 | |
158 | /* find the sassoc. */ |
159 | spi = ah->ah_spi; |
160 | |
161 | if ((sav = key_allocsa(AF_INET, |
162 | (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst, IFSCOPE_NONE, |
163 | IPPROTO_AH, spi)) == 0) { |
164 | ipseclog((LOG_WARNING, |
165 | "IPv4 AH input: no key association found for spi %u\n" , |
166 | (u_int32_t)ntohl(spi))); |
167 | IPSEC_STAT_INCREMENT(ipsecstat.in_nosa); |
168 | goto fail; |
169 | } |
170 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
171 | printf("DP ah4_input called to allocate SA:0x%llx\n" , |
172 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
173 | if (sav->state != SADB_SASTATE_MATURE |
174 | && sav->state != SADB_SASTATE_DYING) { |
175 | ipseclog((LOG_DEBUG, |
176 | "IPv4 AH input: non-mature/dying SA found for spi %u\n" , |
177 | (u_int32_t)ntohl(spi))); |
178 | IPSEC_STAT_INCREMENT(ipsecstat.in_badspi); |
179 | goto fail; |
180 | } |
181 | |
182 | algo = ah_algorithm_lookup(sav->alg_auth); |
183 | if (!algo) { |
184 | ipseclog((LOG_DEBUG, "IPv4 AH input: " |
185 | "unsupported authentication algorithm for spi %u\n" , |
186 | (u_int32_t)ntohl(spi))); |
187 | IPSEC_STAT_INCREMENT(ipsecstat.in_badspi); |
188 | goto fail; |
189 | } |
190 | |
191 | siz = (*algo->sumsiz)(sav); |
192 | siz1 = ((siz + 3) & ~(4 - 1)); |
193 | |
194 | /* |
195 | * sanity checks for header, 1. |
196 | */ |
197 | { |
198 | int sizoff; |
199 | |
200 | sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; |
201 | |
202 | /* |
203 | * Here, we do not do "siz1 == siz". This is because the way |
204 | * RFC240[34] section 2 is written. They do not require truncation |
205 | * to 96 bits. |
206 | * For example, Microsoft IPsec stack attaches 160 bits of |
207 | * authentication data for both hmac-md5 and hmac-sha1. For hmac-sha1, |
208 | * 32 bits of padding is attached. |
209 | * |
210 | * There are two downsides to this specification. |
211 | * They have no real harm, however, they leave us fuzzy feeling. |
212 | * - if we attach more than 96 bits of authentication data onto AH, |
213 | * we will never notice about possible modification by rogue |
214 | * intermediate nodes. |
215 | * Since extra bits in AH checksum is never used, this constitutes |
216 | * no real issue, however, it is wacky. |
217 | * - even if the peer attaches big authentication data, we will never |
218 | * notice the difference, since longer authentication data will just |
219 | * work. |
220 | * |
221 | * We may need some clarification in the spec. |
222 | */ |
223 | if (siz1 < siz) { |
224 | ipseclog((LOG_NOTICE, "sum length too short in IPv4 AH input " |
225 | "(%u, should be at least %u): %s\n" , |
226 | (u_int32_t)siz1, (u_int32_t)siz, |
227 | ipsec4_logpacketstr(ip, spi))); |
228 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
229 | goto fail; |
230 | } |
231 | if ((ah->ah_len << 2) - sizoff != siz1) { |
232 | ipseclog((LOG_NOTICE, "sum length mismatch in IPv4 AH input " |
233 | "(%d should be %u): %s\n" , |
234 | (ah->ah_len << 2) - sizoff, (u_int32_t)siz1, |
235 | ipsec4_logpacketstr(ip, spi))); |
236 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
237 | goto fail; |
238 | } |
239 | |
240 | if (m->m_len < off + sizeof(struct ah) + sizoff + siz1) { |
241 | VERIFY((off + sizeof(struct ah) + sizoff + siz1) <= INT_MAX); |
242 | m = m_pullup(m, (int)(off + sizeof(struct ah) + sizoff + siz1)); |
243 | if (!m) { |
244 | ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n" )); |
245 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
246 | goto fail; |
247 | } |
248 | /* Expect 32-bit aligned data ptr on strict-align platforms */ |
249 | MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); |
250 | |
251 | ip = mtod(m, struct ip *); |
252 | ah = (struct ah *)(void *)(((caddr_t)ip) + off); |
253 | } |
254 | } |
255 | |
256 | /* |
257 | * check for sequence number. |
258 | */ |
259 | if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[0] != NULL) { |
260 | if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav, 0)) { |
261 | ; /*okey*/ |
262 | } else { |
263 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahreplay); |
264 | ipseclog((LOG_WARNING, |
265 | "replay packet in IPv4 AH input: %s %s\n" , |
266 | ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); |
267 | goto fail; |
268 | } |
269 | } |
270 | |
271 | /* |
272 | * alright, it seems sane. now we are going to check the |
273 | * cryptographic checksum. |
274 | */ |
275 | cksum = (u_char *)kalloc_data(siz1, Z_NOWAIT); |
276 | if (!cksum) { |
277 | ipseclog((LOG_DEBUG, "IPv4 AH input: " |
278 | "couldn't alloc temporary region for cksum\n" )); |
279 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
280 | goto fail; |
281 | } |
282 | |
283 | /* |
284 | * some of IP header fields are flipped to the host endian. |
285 | * convert them back to network endian. VERY stupid. |
286 | */ |
287 | if ((ip->ip_len + hlen) > UINT16_MAX) { |
288 | ipseclog((LOG_DEBUG, "IPv4 AH input: " |
289 | "bad length ip header len %u, total len %u\n" , |
290 | ip->ip_len, hlen)); |
291 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
292 | goto fail; |
293 | } |
294 | |
295 | ip->ip_len = htons((u_int16_t)(ip->ip_len + hlen)); |
296 | ip->ip_off = htons(ip->ip_off); |
297 | if (ah4_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) { |
298 | kfree_data(cksum, siz1); |
299 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
300 | goto fail; |
301 | } |
302 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahhist[sav->alg_auth]); |
303 | /* |
304 | * flip them back. |
305 | */ |
306 | ip->ip_len = ntohs(ip->ip_len) - hlen; |
307 | ip->ip_off = ntohs(ip->ip_off); |
308 | |
309 | { |
310 | caddr_t sumpos = NULL; |
311 | |
312 | if (sav->flags & SADB_X_EXT_OLD) { |
313 | /* RFC 1826 */ |
314 | sumpos = (caddr_t)(ah + 1); |
315 | } else { |
316 | /* RFC 2402 */ |
317 | sumpos = (caddr_t)(((struct newah *)ah) + 1); |
318 | } |
319 | |
320 | if (bcmp(s1: sumpos, s2: cksum, n: siz) != 0) { |
321 | ipseclog((LOG_WARNING, |
322 | "checksum mismatch in IPv4 AH input: %s %s\n" , |
323 | ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); |
324 | kfree_data(cksum, siz1); |
325 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthfail); |
326 | goto fail; |
327 | } |
328 | } |
329 | |
330 | kfree_data(cksum, siz1); |
331 | |
332 | m->m_flags |= M_AUTHIPHDR; |
333 | m->m_flags |= M_AUTHIPDGM; |
334 | |
335 | if (m->m_flags & M_AUTHIPHDR && m->m_flags & M_AUTHIPDGM) { |
336 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthsucc); |
337 | } else { |
338 | ipseclog((LOG_WARNING, |
339 | "authentication failed in IPv4 AH input: %s %s\n" , |
340 | ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); |
341 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthfail); |
342 | goto fail; |
343 | } |
344 | |
345 | /* |
346 | * update sequence number. |
347 | */ |
348 | if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[0] != NULL) { |
349 | if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav, 0)) { |
350 | IPSEC_STAT_INCREMENT(ipsecstat.in_ahreplay); |
351 | goto fail; |
352 | } |
353 | } |
354 | |
355 | /* was it transmitted over the IPsec tunnel SA? */ |
356 | if (sav->flags & SADB_X_EXT_OLD) { |
357 | /* RFC 1826 */ |
358 | stripsiz = sizeof(struct ah) + siz1; |
359 | } else { |
360 | /* RFC 2402 */ |
361 | stripsiz = sizeof(struct newah) + siz1; |
362 | } |
363 | if (ipsec4_tunnel_validate(m, (int)(off + stripsiz), nxt, sav, &ifamily)) { |
364 | ifaddr_t ifa; |
365 | struct sockaddr_storage addr; |
366 | struct sockaddr_in *ipaddr; |
367 | |
368 | /* |
369 | * strip off all the headers that precedes AH. |
370 | * IP xx AH IP' payload -> IP' payload |
371 | * |
372 | * XXX more sanity checks |
373 | * XXX relationship with gif? |
374 | */ |
375 | u_int8_t tos, otos; |
376 | int sum; |
377 | |
378 | if (ifamily == AF_INET6) { |
379 | ipseclog((LOG_NOTICE, "ipsec tunnel protocol mismatch " |
380 | "in IPv4 AH input: %s\n" , ipsec_logsastr(sav))); |
381 | goto fail; |
382 | } |
383 | tos = ip->ip_tos; |
384 | m_adj(m, (int)(off + stripsiz)); |
385 | if (m->m_len < sizeof(*ip)) { |
386 | m = m_pullup(m, sizeof(*ip)); |
387 | if (!m) { |
388 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
389 | goto fail; |
390 | } |
391 | } |
392 | ip = mtod(m, struct ip *); |
393 | otos = ip->ip_tos; |
394 | /* ECN consideration. */ |
395 | if (ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos) == 0) { |
396 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
397 | goto fail; |
398 | } |
399 | |
400 | if (otos != ip->ip_tos) { |
401 | sum = ~ntohs(ip->ip_sum) & 0xffff; |
402 | sum += (~otos & 0xffff) + ip->ip_tos; |
403 | sum = (sum >> 16) + (sum & 0xffff); |
404 | sum += (sum >> 16); /* add carry */ |
405 | ip->ip_sum = htons(~sum & 0xffff); |
406 | } |
407 | |
408 | if (!key_checktunnelsanity(sav, AF_INET, |
409 | (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) { |
410 | ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch " |
411 | "in IPv4 AH input: %s %s\n" , |
412 | ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav))); |
413 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
414 | goto fail; |
415 | } |
416 | |
417 | #if 1 |
418 | /* |
419 | * Should the inner packet be considered authentic? |
420 | * My current answer is: NO. |
421 | * |
422 | * host1 -- gw1 === gw2 -- host2 |
423 | * In this case, gw2 can trust the authenticity of the |
424 | * outer packet, but NOT inner. Packet may be altered |
425 | * between host1 and gw1. |
426 | * |
427 | * host1 -- gw1 === host2 |
428 | * This case falls into the same scenario as above. |
429 | * |
430 | * host1 === host2 |
431 | * This case is the only case when we may be able to leave |
432 | * M_AUTHIPHDR and M_AUTHIPDGM set. |
433 | * However, if host1 is wrongly configured, and allows |
434 | * attacker to inject some packet with src=host1 and |
435 | * dst=host2, you are in risk. |
436 | */ |
437 | m->m_flags &= ~M_AUTHIPHDR; |
438 | m->m_flags &= ~M_AUTHIPDGM; |
439 | #endif |
440 | |
441 | key_sa_recordxfer(sav, m->m_pkthdr.len); |
442 | if (ipsec_incr_history_count(m, IPPROTO_AH, spi) != 0 || |
443 | ipsec_incr_history_count(m, IPPROTO_IPV4, 0) != 0) { |
444 | IPSEC_STAT_INCREMENT(ipsecstat.in_nomem); |
445 | goto fail; |
446 | } |
447 | |
448 | bzero(s: &addr, n: sizeof(addr)); |
449 | ipaddr = (__typeof__(ipaddr)) & addr; |
450 | ipaddr->sin_family = AF_INET; |
451 | ipaddr->sin_len = sizeof(*ipaddr); |
452 | ipaddr->sin_addr = ip->ip_dst; |
453 | |
454 | // update the receiving interface address based on the inner address |
455 | ifa = ifa_ifwithaddr((struct sockaddr *)&addr); |
456 | if (ifa) { |
457 | m->m_pkthdr.rcvif = ifa->ifa_ifp; |
458 | ifa_remref(ifa); |
459 | } |
460 | |
461 | // Input via IPsec interface |
462 | lck_mtx_lock(sadb_mutex); |
463 | ifnet_t ipsec_if = sav->sah->ipsec_if; |
464 | if (ipsec_if != NULL) { |
465 | // If an interface is found, add a reference count before dropping the lock |
466 | ifnet_reference(interface: ipsec_if); |
467 | } |
468 | lck_mtx_unlock(sadb_mutex); |
469 | if (ipsec_if != NULL) { |
470 | errno_t inject_error = ipsec_inject_inbound_packet(interface: ipsec_if, packet: m); |
471 | ifnet_release(interface: ipsec_if); |
472 | if (inject_error == 0) { |
473 | m = NULL; |
474 | goto done; |
475 | } else { |
476 | goto fail; |
477 | } |
478 | } |
479 | |
480 | if (proto_input(PF_INET, packet: m) != 0) { |
481 | goto fail; |
482 | } |
483 | nxt = IPPROTO_DONE; |
484 | } else { |
485 | /* |
486 | * strip off AH. |
487 | */ |
488 | |
489 | ip = mtod(m, struct ip *); |
490 | /* |
491 | * We do deep-copy since KAME requires that |
492 | * the packet is placed in a single external mbuf. |
493 | */ |
494 | ovbcopy(from: (caddr_t)ip, to: (caddr_t)(((u_char *)ip) + stripsiz), len: off); |
495 | m->m_data += stripsiz; |
496 | m->m_len -= stripsiz; |
497 | m->m_pkthdr.len -= stripsiz; |
498 | |
499 | if (m->m_len < sizeof(*ip)) { |
500 | m = m_pullup(m, sizeof(*ip)); |
501 | if (m == NULL) { |
502 | IPSEC_STAT_INCREMENT(ipsecstat.in_inval); |
503 | goto fail; |
504 | } |
505 | } |
506 | ip = mtod(m, struct ip *); |
507 | #ifdef IPLEN_FLIPPED |
508 | ip->ip_len = (u_short)(ip->ip_len - stripsiz); |
509 | #else |
510 | ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz); |
511 | #endif |
512 | ip->ip_p = (u_char)nxt; |
513 | /* forget about IP hdr checksum, the check has already been passed */ |
514 | |
515 | key_sa_recordxfer(sav, m->m_pkthdr.len); |
516 | if (ipsec_incr_history_count(m, IPPROTO_AH, spi) != 0) { |
517 | IPSEC_STAT_INCREMENT(ipsecstat.in_nomem); |
518 | goto fail; |
519 | } |
520 | |
521 | DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL, |
522 | struct ip *, ip, struct ifnet *, m->m_pkthdr.rcvif, |
523 | struct ip *, ip, struct ip6_hdr *, NULL); |
524 | |
525 | if (nxt != IPPROTO_DONE) { |
526 | // Input via IPsec interface |
527 | lck_mtx_lock(sadb_mutex); |
528 | ifnet_t ipsec_if = sav->sah->ipsec_if; |
529 | if (ipsec_if != NULL) { |
530 | // If an interface is found, add a reference count before dropping the lock |
531 | ifnet_reference(interface: ipsec_if); |
532 | } |
533 | lck_mtx_unlock(sadb_mutex); |
534 | if (ipsec_if != NULL) { |
535 | ip->ip_len = htons(ip->ip_len + hlen); |
536 | ip->ip_off = htons(ip->ip_off); |
537 | ip->ip_sum = 0; |
538 | ip->ip_sum = ip_cksum_hdr_in(m, hlen); |
539 | errno_t inject_error = ipsec_inject_inbound_packet(interface: ipsec_if, packet: m); |
540 | ifnet_release(interface: ipsec_if); |
541 | if (inject_error == 0) { |
542 | m = NULL; |
543 | goto done; |
544 | } else { |
545 | goto fail; |
546 | } |
547 | } |
548 | |
549 | if ((ip_protox[nxt]->pr_flags & PR_LASTHDR) != 0 && |
550 | ipsec4_in_reject(m, NULL)) { |
551 | IPSEC_STAT_INCREMENT(ipsecstat.in_polvio); |
552 | goto fail; |
553 | } |
554 | ip_proto_dispatch_in(m, hlen: off, proto: (u_int8_t)nxt, ipfref: 0); |
555 | } else { |
556 | m_freem(m); |
557 | } |
558 | m = NULL; |
559 | } |
560 | done: |
561 | if (sav) { |
562 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
563 | printf("DP ah4_input call free SA:0x%llx\n" , |
564 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
565 | key_freesav(sav, KEY_SADB_UNLOCKED); |
566 | } |
567 | IPSEC_STAT_INCREMENT(ipsecstat.in_success); |
568 | return; |
569 | |
570 | fail: |
571 | if (sav) { |
572 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
573 | printf("DP ah4_input call free SA:0x%llx\n" , |
574 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
575 | key_freesav(sav, KEY_SADB_UNLOCKED); |
576 | } |
577 | if (m) { |
578 | m_freem(m); |
579 | } |
580 | return; |
581 | } |
582 | #endif /* INET */ |
583 | |
584 | int |
585 | ah6_input(struct mbuf **mp, int *offp, int proto) |
586 | { |
587 | #pragma unused(proto) |
588 | struct mbuf *m = *mp; |
589 | int off = *offp; |
590 | struct ip6_hdr *ip6 = NULL; |
591 | struct ah *ah = NULL; |
592 | u_int32_t spi = 0; |
593 | const struct ah_algorithm *algo = NULL; |
594 | size_t siz = 0; |
595 | size_t siz1 = 0; |
596 | u_char *cksum = NULL; |
597 | struct secasvar *sav = NULL; |
598 | u_int16_t nxt = IPPROTO_DONE; |
599 | size_t stripsiz = 0; |
600 | sa_family_t ifamily = AF_UNSPEC; |
601 | |
602 | IP6_EXTHDR_CHECK(m, off, sizeof(struct ah), {return IPPROTO_DONE;}); |
603 | ah = (struct ah *)(void *)(mtod(m, caddr_t) + off); |
604 | /* Expect 32-bit aligned data pointer on strict-align platforms */ |
605 | MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); |
606 | |
607 | ip6 = mtod(m, struct ip6_hdr *); |
608 | nxt = ah->ah_nxt; |
609 | |
610 | /* find the sassoc. */ |
611 | spi = ah->ah_spi; |
612 | |
613 | if (ntohs(ip6->ip6_plen) == 0) { |
614 | ipseclog((LOG_ERR, "IPv6 AH input: " |
615 | "AH with IPv6 jumbogram is not supported.\n" )); |
616 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
617 | goto fail; |
618 | } |
619 | |
620 | if ((sav = key_allocsa(AF_INET6, |
621 | (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst, ip6_input_getsrcifscope(m), |
622 | IPPROTO_AH, spi)) == 0) { |
623 | ipseclog((LOG_WARNING, |
624 | "IPv6 AH input: no key association found for spi %u\n" , |
625 | (u_int32_t)ntohl(spi))); |
626 | IPSEC_STAT_INCREMENT(ipsec6stat.in_nosa); |
627 | goto fail; |
628 | } |
629 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
630 | printf("DP ah6_input called to allocate SA:0x%llx\n" , |
631 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
632 | if (sav->state != SADB_SASTATE_MATURE |
633 | && sav->state != SADB_SASTATE_DYING) { |
634 | ipseclog((LOG_DEBUG, |
635 | "IPv6 AH input: non-mature/dying SA found for spi %u; " , |
636 | (u_int32_t)ntohl(spi))); |
637 | IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi); |
638 | goto fail; |
639 | } |
640 | |
641 | algo = ah_algorithm_lookup(sav->alg_auth); |
642 | if (!algo) { |
643 | ipseclog((LOG_DEBUG, "IPv6 AH input: " |
644 | "unsupported authentication algorithm for spi %u\n" , |
645 | (u_int32_t)ntohl(spi))); |
646 | IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi); |
647 | goto fail; |
648 | } |
649 | |
650 | siz = (*algo->sumsiz)(sav); |
651 | siz1 = ((siz + 3) & ~(4 - 1)); |
652 | |
653 | /* |
654 | * sanity checks for header, 1. |
655 | */ |
656 | { |
657 | int sizoff; |
658 | |
659 | sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4; |
660 | |
661 | /* |
662 | * Here, we do not do "siz1 == siz". See ah4_input() for complete |
663 | * description. |
664 | */ |
665 | if (siz1 < siz) { |
666 | ipseclog((LOG_NOTICE, "sum length too short in IPv6 AH input " |
667 | "(%u, should be at least %u): %s\n" , |
668 | (u_int32_t)siz1, (u_int32_t)siz, |
669 | ipsec6_logpacketstr(ip6, spi))); |
670 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
671 | goto fail; |
672 | } |
673 | if ((ah->ah_len << 2) - sizoff != siz1) { |
674 | ipseclog((LOG_NOTICE, "sum length mismatch in IPv6 AH input " |
675 | "(%d should be %u): %s\n" , |
676 | (ah->ah_len << 2) - sizoff, (u_int32_t)siz1, |
677 | ipsec6_logpacketstr(ip6, spi))); |
678 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
679 | goto fail; |
680 | } |
681 | VERIFY((sizeof(struct ah) + sizoff + siz1) <= INT_MAX); |
682 | IP6_EXTHDR_CHECK(m, off, (int)(sizeof(struct ah) + sizoff + siz1), |
683 | {goto fail;}); |
684 | ip6 = mtod(m, struct ip6_hdr *); |
685 | ah = (struct ah *)(void *)(mtod(m, caddr_t) + off); |
686 | } |
687 | |
688 | /* |
689 | * check for sequence number. |
690 | */ |
691 | if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[0] != NULL) { |
692 | if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav, 0)) { |
693 | ; /*okey*/ |
694 | } else { |
695 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahreplay); |
696 | ipseclog((LOG_WARNING, |
697 | "replay packet in IPv6 AH input: %s %s\n" , |
698 | ipsec6_logpacketstr(ip6, spi), |
699 | ipsec_logsastr(sav))); |
700 | goto fail; |
701 | } |
702 | } |
703 | |
704 | /* |
705 | * alright, it seems sane. now we are going to check the |
706 | * cryptographic checksum. |
707 | */ |
708 | cksum = (u_char *)kalloc_data(siz1, Z_NOWAIT); |
709 | if (!cksum) { |
710 | ipseclog((LOG_DEBUG, "IPv6 AH input: " |
711 | "couldn't alloc temporary region for cksum\n" )); |
712 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
713 | goto fail; |
714 | } |
715 | |
716 | if (ah6_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) { |
717 | kfree_data(cksum, siz1); |
718 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
719 | goto fail; |
720 | } |
721 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahhist[sav->alg_auth]); |
722 | |
723 | { |
724 | caddr_t sumpos = NULL; |
725 | |
726 | if (sav->flags & SADB_X_EXT_OLD) { |
727 | /* RFC 1826 */ |
728 | sumpos = (caddr_t)(ah + 1); |
729 | } else { |
730 | /* RFC 2402 */ |
731 | sumpos = (caddr_t)(((struct newah *)ah) + 1); |
732 | } |
733 | |
734 | if (bcmp(s1: sumpos, s2: cksum, n: siz) != 0) { |
735 | ipseclog((LOG_WARNING, |
736 | "checksum mismatch in IPv6 AH input: %s %s\n" , |
737 | ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); |
738 | kfree_data(cksum, siz1); |
739 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthfail); |
740 | goto fail; |
741 | } |
742 | } |
743 | |
744 | kfree_data(cksum, siz1); |
745 | |
746 | m->m_flags |= M_AUTHIPHDR; |
747 | m->m_flags |= M_AUTHIPDGM; |
748 | |
749 | if (m->m_flags & M_AUTHIPHDR && m->m_flags & M_AUTHIPDGM) { |
750 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthsucc); |
751 | } else { |
752 | ipseclog((LOG_WARNING, |
753 | "authentication failed in IPv6 AH input: %s %s\n" , |
754 | ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav))); |
755 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthfail); |
756 | goto fail; |
757 | } |
758 | |
759 | /* |
760 | * update sequence number. |
761 | */ |
762 | if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[0] != NULL) { |
763 | if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav, 0)) { |
764 | IPSEC_STAT_INCREMENT(ipsec6stat.in_ahreplay); |
765 | goto fail; |
766 | } |
767 | } |
768 | |
769 | /* was it transmitted over the IPsec tunnel SA? */ |
770 | if (sav->flags & SADB_X_EXT_OLD) { |
771 | /* RFC 1826 */ |
772 | stripsiz = sizeof(struct ah) + siz1; |
773 | } else { |
774 | /* RFC 2402 */ |
775 | stripsiz = sizeof(struct newah) + siz1; |
776 | } |
777 | if (ipsec6_tunnel_validate(m, (int)(off + stripsiz), nxt, sav, &ifamily)) { |
778 | ifaddr_t ifa; |
779 | struct sockaddr_storage addr; |
780 | struct sockaddr_in6 *ip6addr; |
781 | /* |
782 | * strip off all the headers that precedes AH. |
783 | * IP6 xx AH IP6' payload -> IP6' payload |
784 | * |
785 | * XXX more sanity checks |
786 | * XXX relationship with gif? |
787 | */ |
788 | u_int32_t flowinfo; /*net endian*/ |
789 | |
790 | if (ifamily == AF_INET) { |
791 | ipseclog((LOG_NOTICE, "ipsec tunnel protocol mismatch " |
792 | "in IPv6 AH input: %s\n" , ipsec_logsastr(sav))); |
793 | goto fail; |
794 | } |
795 | |
796 | flowinfo = ip6->ip6_flow; |
797 | m_adj(m, (int)(off + stripsiz)); |
798 | if (m->m_len < sizeof(*ip6)) { |
799 | /* |
800 | * m_pullup is prohibited in KAME IPv6 input processing |
801 | * but there's no other way! |
802 | */ |
803 | m = m_pullup(m, sizeof(*ip6)); |
804 | if (!m) { |
805 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
806 | goto fail; |
807 | } |
808 | } |
809 | ip6 = mtod(m, struct ip6_hdr *); |
810 | /* ECN consideration. */ |
811 | if (ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow) == 0) { |
812 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
813 | goto fail; |
814 | } |
815 | if (!key_checktunnelsanity(sav, AF_INET6, |
816 | (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) { |
817 | ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch " |
818 | "in IPv6 AH input: %s %s\n" , |
819 | ipsec6_logpacketstr(ip6, spi), |
820 | ipsec_logsastr(sav))); |
821 | IPSEC_STAT_INCREMENT(ipsec6stat.in_inval); |
822 | goto fail; |
823 | } |
824 | |
825 | /* |
826 | * should the inner packet be considered authentic? |
827 | * see comment in ah4_input(). |
828 | */ |
829 | m->m_flags &= ~M_AUTHIPHDR; |
830 | m->m_flags &= ~M_AUTHIPDGM; |
831 | |
832 | key_sa_recordxfer(sav, m->m_pkthdr.len); |
833 | if (ipsec_incr_history_count(m, IPPROTO_AH, spi) != 0 || |
834 | ipsec_incr_history_count(m, IPPROTO_IPV6, 0) != 0) { |
835 | IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem); |
836 | goto fail; |
837 | } |
838 | |
839 | bzero(s: &addr, n: sizeof(addr)); |
840 | ip6addr = (__typeof__(ip6addr)) & addr; |
841 | ip6addr->sin6_family = AF_INET6; |
842 | ip6addr->sin6_len = sizeof(*ip6addr); |
843 | ip6addr->sin6_addr = ip6->ip6_dst; |
844 | |
845 | // update the receiving interface address based on the inner address |
846 | ifa = ifa_ifwithaddr((struct sockaddr *)&addr); |
847 | if (ifa) { |
848 | m->m_pkthdr.rcvif = ifa->ifa_ifp; |
849 | ifa_remref(ifa); |
850 | } |
851 | |
852 | // Input via IPsec interface |
853 | lck_mtx_lock(sadb_mutex); |
854 | ifnet_t ipsec_if = sav->sah->ipsec_if; |
855 | if (ipsec_if != NULL) { |
856 | // If an interface is found, add a reference count before dropping the lock |
857 | ifnet_reference(interface: ipsec_if); |
858 | } |
859 | lck_mtx_unlock(sadb_mutex); |
860 | if (ipsec_if != NULL) { |
861 | errno_t inject_error = ipsec_inject_inbound_packet(interface: ipsec_if, packet: m); |
862 | ifnet_release(interface: ipsec_if); |
863 | if (inject_error == 0) { |
864 | m = NULL; |
865 | nxt = IPPROTO_DONE; |
866 | goto done; |
867 | } else { |
868 | goto fail; |
869 | } |
870 | } |
871 | |
872 | if (proto_input(PF_INET6, packet: m) != 0) { |
873 | goto fail; |
874 | } |
875 | nxt = IPPROTO_DONE; |
876 | } else { |
877 | /* |
878 | * strip off AH. |
879 | */ |
880 | char *prvnxtp; |
881 | |
882 | /* |
883 | * Copy the value of the next header field of AH to the |
884 | * next header field of the previous header. |
885 | * This is necessary because AH will be stripped off below. |
886 | */ |
887 | prvnxtp = ip6_get_prevhdr(m, off); /* XXX */ |
888 | *prvnxtp = (u_int8_t)nxt; |
889 | |
890 | ip6 = mtod(m, struct ip6_hdr *); |
891 | /* |
892 | * We do deep-copy since KAME requires that |
893 | * the packet is placed in a single mbuf. |
894 | */ |
895 | ovbcopy(from: (caddr_t)ip6, to: ((caddr_t)ip6) + stripsiz, len: off); |
896 | m->m_data += stripsiz; |
897 | m->m_len -= stripsiz; |
898 | m->m_pkthdr.len -= stripsiz; |
899 | ip6 = mtod(m, struct ip6_hdr *); |
900 | /* XXX jumbogram */ |
901 | ip6->ip6_plen = htons((u_int16_t)(ntohs(ip6->ip6_plen) - stripsiz)); |
902 | |
903 | key_sa_recordxfer(sav, m->m_pkthdr.len); |
904 | if (ipsec_incr_history_count(m, IPPROTO_AH, spi) != 0) { |
905 | IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem); |
906 | goto fail; |
907 | } |
908 | |
909 | // Input via IPsec interface |
910 | lck_mtx_lock(sadb_mutex); |
911 | ifnet_t ipsec_if = sav->sah->ipsec_if; |
912 | if (ipsec_if != NULL) { |
913 | // If an interface is found, add a reference count before dropping the lock |
914 | ifnet_reference(interface: ipsec_if); |
915 | } |
916 | lck_mtx_unlock(sadb_mutex); |
917 | if (ipsec_if != NULL) { |
918 | errno_t inject_error = ipsec_inject_inbound_packet(interface: ipsec_if, packet: m); |
919 | ifnet_release(interface: ipsec_if); |
920 | if (inject_error == 0) { |
921 | m = NULL; |
922 | nxt = IPPROTO_DONE; |
923 | goto done; |
924 | } else { |
925 | goto fail; |
926 | } |
927 | } |
928 | } |
929 | |
930 | done: |
931 | *offp = off; |
932 | *mp = m; |
933 | if (sav) { |
934 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
935 | printf("DP ah6_input call free SA:0x%llx\n" , |
936 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
937 | key_freesav(sav, KEY_SADB_UNLOCKED); |
938 | } |
939 | IPSEC_STAT_INCREMENT(ipsec6stat.in_success); |
940 | return nxt; |
941 | |
942 | fail: |
943 | if (sav) { |
944 | KEYDEBUG(KEYDEBUG_IPSEC_STAMP, |
945 | printf("DP ah6_input call free SA:0x%llx\n" , |
946 | (uint64_t)VM_KERNEL_ADDRPERM(sav))); |
947 | key_freesav(sav, KEY_SADB_UNLOCKED); |
948 | } |
949 | if (m) { |
950 | m_freem(m); |
951 | *mp = NULL; |
952 | } |
953 | return IPPROTO_DONE; |
954 | } |
955 | |
956 | void |
957 | ah6_ctlinput(int cmd, struct sockaddr *sa, void *d) |
958 | { |
959 | const struct newah *ahp; |
960 | struct newah ah; |
961 | struct secasvar *sav; |
962 | struct ip6_hdr *ip6; |
963 | struct mbuf *m; |
964 | struct ip6ctlparam *ip6cp = NULL; |
965 | int off = 0; |
966 | struct sockaddr_in6 *sa6_src, *sa6_dst; |
967 | |
968 | if (sa->sa_family != AF_INET6 || |
969 | sa->sa_len != sizeof(struct sockaddr_in6)) { |
970 | return; |
971 | } |
972 | if ((unsigned)cmd >= PRC_NCMDS) { |
973 | return; |
974 | } |
975 | |
976 | /* if the parameter is from icmp6, decode it. */ |
977 | if (d != NULL) { |
978 | ip6cp = (struct ip6ctlparam *)d; |
979 | m = ip6cp->ip6c_m; |
980 | ip6 = ip6cp->ip6c_ip6; |
981 | off = ip6cp->ip6c_off; |
982 | } else { |
983 | m = NULL; |
984 | ip6 = NULL; |
985 | } |
986 | |
987 | if (ip6) { |
988 | /* |
989 | * XXX: We assume that when ip6 is non NULL, |
990 | * M and OFF are valid. |
991 | */ |
992 | |
993 | /* check if we can safely examine src and dst ports */ |
994 | if (m->m_pkthdr.len < off + sizeof(ah)) { |
995 | return; |
996 | } |
997 | |
998 | if (m->m_len < off + sizeof(ah)) { |
999 | /* |
1000 | * this should be rare case, |
1001 | * so we compromise on this copy... |
1002 | */ |
1003 | m_copydata(m, off, sizeof(ah), (caddr_t)&ah); |
1004 | ahp = &ah; |
1005 | } else { |
1006 | ahp = (struct newah *)(void *)(mtod(m, caddr_t) + off); |
1007 | } |
1008 | |
1009 | if (cmd == PRC_MSGSIZE) { |
1010 | int valid = 0; |
1011 | |
1012 | /* |
1013 | * Check to see if we have a valid SA corresponding to |
1014 | * the address in the ICMP message payload. |
1015 | */ |
1016 | sa6_src = ip6cp->ip6c_src; |
1017 | sa6_dst = (struct sockaddr_in6 *)(void *)sa; |
1018 | sav = key_allocsa(AF_INET6, |
1019 | (caddr_t)&sa6_src->sin6_addr, |
1020 | (caddr_t)&sa6_dst->sin6_addr, |
1021 | sa6_dst->sin6_scope_id, |
1022 | IPPROTO_AH, ahp->ah_spi); |
1023 | if (sav) { |
1024 | if (sav->state == SADB_SASTATE_MATURE || |
1025 | sav->state == SADB_SASTATE_DYING) { |
1026 | valid++; |
1027 | } |
1028 | key_freesav(sav, KEY_SADB_UNLOCKED); |
1029 | } |
1030 | |
1031 | /* XXX Further validation? */ |
1032 | |
1033 | /* |
1034 | * Depending on the value of "valid" and routing table |
1035 | * size (mtudisc_{hi,lo}wat), we will: |
1036 | * - recalcurate the new MTU and create the |
1037 | * corresponding routing entry, or |
1038 | * - ignore the MTU change notification. |
1039 | */ |
1040 | icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); |
1041 | } |
1042 | |
1043 | /* we normally notify single pcb here */ |
1044 | } else { |
1045 | /* we normally notify any pcb here */ |
1046 | } |
1047 | } |
1048 | |