1 /* $FreeBSD: stable/10/sys/netipsec/ipsec.c 299627 2016-05-13 08:49:29Z ngie $ */
2 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */
3
4 /*-
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * IPsec controller part.
35 */
36
37 #include "opt_inet.h"
38 #include "opt_inet6.h"
39 #include "opt_ipsec.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/malloc.h>
44 #include <sys/mbuf.h>
45 #include <sys/domain.h>
46 #include <sys/priv.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/errno.h>
51 #include <sys/time.h>
52 #include <sys/kernel.h>
53 #include <sys/syslog.h>
54 #include <sys/sysctl.h>
55 #include <sys/proc.h>
56
57 #include <net/if.h>
58 #include <net/vnet.h>
59
60 #include <netinet/in.h>
61 #include <netinet/in_systm.h>
62 #include <netinet/ip.h>
63 #include <netinet/ip_var.h>
64 #include <netinet/in_var.h>
65 #include <netinet/udp.h>
66 #include <netinet/udp_var.h>
67 #include <netinet/tcp.h>
68 #include <netinet/udp.h>
69
70 #include <netinet/ip6.h>
71 #ifdef INET6
72 #include <netinet6/ip6_var.h>
73 #endif
74 #include <netinet/in_pcb.h>
75 #ifdef INET6
76 #include <netinet/icmp6.h>
77 #endif
78
79 #include <sys/types.h>
80 #include <netipsec/ipsec.h>
81 #ifdef INET6
82 #include <netipsec/ipsec6.h>
83 #endif
84 #include <netipsec/ah_var.h>
85 #include <netipsec/esp_var.h>
86 #include <netipsec/ipcomp.h> /*XXX*/
87 #include <netipsec/ipcomp_var.h>
88
89 #include <netipsec/key.h>
90 #include <netipsec/keydb.h>
91 #include <netipsec/key_debug.h>
92
93 #include <netipsec/xform.h>
94
95 #include <machine/in_cksum.h>
96
97 #include <opencrypto/cryptodev.h>
98
99 #ifdef IPSEC_DEBUG
100 VNET_DEFINE(int, ipsec_debug) = 1;
101 #else
102 VNET_DEFINE(int, ipsec_debug) = 0;
103 #endif
104
105 /* NB: name changed so netstat doesn't use it. */
106 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec4stat);
107 VNET_PCPUSTAT_SYSINIT(ipsec4stat);
108
109 #ifdef VIMAGE
110 VNET_PCPUSTAT_SYSUNINIT(ipsec4stat);
111 #endif /* VIMAGE */
112
113 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */
114 /* DF bit on encap. 0: clear 1: set 2: copy */
115 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0;
116 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE;
117 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE;
118 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE;
119 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE;
120 VNET_DEFINE(struct secpolicy, ip4_def_policy);
121 /* ECN ignore(-1)/forbidden(0)/allowed(1) */
122 VNET_DEFINE(int, ip4_ipsec_ecn) = 0;
123 VNET_DEFINE(int, ip4_esp_randpad) = -1;
124
125 /*
126 * Crypto support requirements:
127 *
128 * 1 require hardware support
129 * -1 require software support
130 * 0 take anything
131 */
132 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE;
133
134 FEATURE(ipsec, "Internet Protocol Security (IPsec)");
135 #ifdef IPSEC_NAT_T
136 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')");
137 #endif
138
139 SYSCTL_DECL(_net_inet_ipsec);
140
141 /* net.inet.ipsec */
142 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy,
143 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0,
144 "IPsec default policy.");
145 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
146 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0,
147 "Default ESP transport mode level");
148 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
149 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0,
150 "Default ESP tunnel mode level.");
151 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
152 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0,
153 "AH transfer mode default level.");
154 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
155 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0,
156 "AH tunnel mode default level.");
157 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos,
158 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0,
159 "If set clear type-of-service field when doing AH computation.");
160 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask,
161 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0,
162 "If not set clear offset field mask when doing AH computation.");
163 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit,
164 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0,
165 "Do not fragment bit on encap.");
166 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn,
167 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0,
168 "Explicit Congestion Notification handling.");
169 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug,
170 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0,
171 "Enable IPsec debugging output when set.");
172 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support,
173 CTLFLAG_RW, &VNET_NAME(crypto_support), 0,
174 "Crypto driver selection.");
175 SYSCTL_VNET_PCPUSTAT(_net_inet_ipsec, OID_AUTO, ipsecstats, struct ipsecstat,
176 ipsec4stat, "IPsec IPv4 statistics.");
177
178 #ifdef REGRESSION
179 /*
180 * When set to 1, IPsec will send packets with the same sequence number.
181 * This allows to verify if the other side has proper replay attacks detection.
182 */
183 VNET_DEFINE(int, ipsec_replay) = 0;
184 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay,
185 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0,
186 "Emulate replay attack");
187 /*
188 * When set 1, IPsec will send packets with corrupted HMAC.
189 * This allows to verify if the other side properly detects modified packets.
190 */
191 VNET_DEFINE(int, ipsec_integrity) = 0;
192 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity,
193 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0,
194 "Emulate man-in-the-middle attack");
195 #endif
196
197 #ifdef INET6
198 VNET_PCPUSTAT_DEFINE(struct ipsecstat, ipsec6stat);
199 VNET_PCPUSTAT_SYSINIT(ipsec6stat);
200
201 #ifdef VIMAGE
202 VNET_PCPUSTAT_SYSUNINIT(ipsec6stat);
203 #endif /* VIMAGE */
204
205 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE;
206 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE;
207 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE;
208 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE;
209 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
210
211 SYSCTL_DECL(_net_inet6_ipsec6);
212
213 /* net.inet6.ipsec6 */
214 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW,
215 &VNET_NAME(ip4_def_policy).policy, 0,
216 "IPsec default policy.");
217 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV,
218 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0,
219 "Default ESP transport mode level.");
220 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV,
221 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0,
222 "Default ESP tunnel mode level.");
223 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV,
224 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0,
225 "AH transfer mode default level.");
226 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV,
227 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0,
228 "AH tunnel mode default level.");
229 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN,
230 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0,
231 "Explicit Congestion Notification handling.");
232 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW,
233 &VNET_NAME(ipsec_debug), 0,
234 "Enable IPsec debugging output when set.");
235 SYSCTL_VNET_PCPUSTAT(_net_inet6_ipsec6, IPSECCTL_STATS, ipsecstats,
236 struct ipsecstat, ipsec6stat, "IPsec IPv6 statistics.");
237 #endif /* INET6 */
238
239 static int ipsec_setspidx_inpcb(struct mbuf *, struct inpcb *);
240 static int ipsec_setspidx(struct mbuf *, struct secpolicyindex *, int);
241 static void ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *, int);
242 static int ipsec4_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *);
243 #ifdef INET6
244 static void ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *, int);
245 static int ipsec6_setspidx_ipaddr(struct mbuf *, struct secpolicyindex *);
246 #endif
247 static void ipsec_delpcbpolicy(struct inpcbpolicy *);
248 static struct secpolicy *ipsec_deepcopy_policy(struct secpolicy *src);
249 static void vshiftl(unsigned char *, int, int);
250
251 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy");
252
253 /*
254 * Return a held reference to the default SP.
255 */
256 static struct secpolicy *
key_allocsp_default(const char * where,int tag)257 key_allocsp_default(const char* where, int tag)
258 {
259 struct secpolicy *sp;
260
261 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
262 printf("DP key_allocsp_default from %s:%u\n", where, tag));
263
264 sp = &V_ip4_def_policy;
265 if (sp->policy != IPSEC_POLICY_DISCARD &&
266 sp->policy != IPSEC_POLICY_NONE) {
267 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n",
268 sp->policy, IPSEC_POLICY_NONE));
269 sp->policy = IPSEC_POLICY_NONE;
270 }
271 key_addref(sp);
272
273 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
274 printf("DP key_allocsp_default returns SP:%p (%u)\n",
275 sp, sp->refcnt));
276 return (sp);
277 }
278 #define KEY_ALLOCSP_DEFAULT() \
279 key_allocsp_default(__FILE__, __LINE__)
280
281 /*
282 * For OUTBOUND packet having a socket. Searching SPD for packet,
283 * and return a pointer to SP.
284 * OUT: NULL: no apropreate SP found, the following value is set to error.
285 * 0 : bypass
286 * EACCES : discard packet.
287 * ENOENT : ipsec_acquire() in progress, maybe.
288 * others : error occured.
289 * others: a pointer to SP
290 *
291 * NOTE: IPv6 mapped adddress concern is implemented here.
292 */
293 struct secpolicy *
ipsec_getpolicy(struct tdb_ident * tdbi,u_int dir)294 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir)
295 {
296 struct secpolicy *sp;
297
298 IPSEC_ASSERT(tdbi != NULL, ("null tdbi"));
299 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
300 ("invalid direction %u", dir));
301
302 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir);
303 if (sp == NULL) /*XXX????*/
304 sp = KEY_ALLOCSP_DEFAULT();
305 IPSEC_ASSERT(sp != NULL, ("null SP"));
306 return (sp);
307 }
308
309 /*
310 * For OUTBOUND packet having a socket. Searching SPD for packet,
311 * and return a pointer to SP.
312 * OUT: NULL: no apropreate SP found, the following value is set to error.
313 * 0 : bypass
314 * EACCES : discard packet.
315 * ENOENT : ipsec_acquire() in progress, maybe.
316 * others : error occured.
317 * others: a pointer to SP
318 *
319 * NOTE: IPv6 mapped adddress concern is implemented here.
320 */
321 static struct secpolicy *
ipsec_getpolicybysock(struct mbuf * m,u_int dir,struct inpcb * inp,int * error)322 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error)
323 {
324 struct inpcbpolicy *pcbsp;
325 struct secpolicy *currsp = NULL; /* Policy on socket. */
326 struct secpolicy *sp;
327
328 IPSEC_ASSERT(m != NULL, ("null mbuf"));
329 IPSEC_ASSERT(inp != NULL, ("null inpcb"));
330 IPSEC_ASSERT(error != NULL, ("null error"));
331 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
332 ("invalid direction %u", dir));
333
334 /* Set spidx in pcb. */
335 *error = ipsec_setspidx_inpcb(m, inp);
336 if (*error)
337 return (NULL);
338
339 pcbsp = inp->inp_sp;
340 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp"));
341 switch (dir) {
342 case IPSEC_DIR_INBOUND:
343 currsp = pcbsp->sp_in;
344 break;
345 case IPSEC_DIR_OUTBOUND:
346 currsp = pcbsp->sp_out;
347 break;
348 }
349 IPSEC_ASSERT(currsp != NULL, ("null currsp"));
350
351 if (pcbsp->priv) { /* When privilieged socket. */
352 switch (currsp->policy) {
353 case IPSEC_POLICY_BYPASS:
354 case IPSEC_POLICY_IPSEC:
355 key_addref(currsp);
356 sp = currsp;
357 break;
358
359 case IPSEC_POLICY_ENTRUST:
360 /* Look for a policy in SPD. */
361 sp = KEY_ALLOCSP(&currsp->spidx, dir);
362 if (sp == NULL) /* No SP found. */
363 sp = KEY_ALLOCSP_DEFAULT();
364 break;
365
366 default:
367 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n",
368 __func__, currsp->policy));
369 *error = EINVAL;
370 return (NULL);
371 }
372 } else { /* Unpriv, SPD has policy. */
373 sp = KEY_ALLOCSP(&currsp->spidx, dir);
374 if (sp == NULL) { /* No SP found. */
375 switch (currsp->policy) {
376 case IPSEC_POLICY_BYPASS:
377 ipseclog((LOG_ERR, "%s: Illegal policy for "
378 "non-priviliged defined %d\n",
379 __func__, currsp->policy));
380 *error = EINVAL;
381 return (NULL);
382
383 case IPSEC_POLICY_ENTRUST:
384 sp = KEY_ALLOCSP_DEFAULT();
385 break;
386
387 case IPSEC_POLICY_IPSEC:
388 key_addref(currsp);
389 sp = currsp;
390 break;
391
392 default:
393 ipseclog((LOG_ERR, "%s: Invalid policy for "
394 "PCB %d\n", __func__, currsp->policy));
395 *error = EINVAL;
396 return (NULL);
397 }
398 }
399 }
400 IPSEC_ASSERT(sp != NULL,
401 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy));
402 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
403 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n",
404 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt));
405 return (sp);
406 }
407
408 /*
409 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet,
410 * and return a pointer to SP.
411 * OUT: positive: a pointer to the entry for security policy leaf matched.
412 * NULL: no apropreate SP found, the following value is set to error.
413 * 0 : bypass
414 * EACCES : discard packet.
415 * ENOENT : ipsec_acquire() in progress, maybe.
416 * others : error occured.
417 */
418 struct secpolicy *
ipsec_getpolicybyaddr(struct mbuf * m,u_int dir,int flag,int * error)419 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error)
420 {
421 struct secpolicyindex spidx;
422 struct secpolicy *sp;
423
424 IPSEC_ASSERT(m != NULL, ("null mbuf"));
425 IPSEC_ASSERT(error != NULL, ("null error"));
426 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
427 ("invalid direction %u", dir));
428
429 sp = NULL;
430 if (key_havesp(dir)) {
431 /* Make an index to look for a policy. */
432 *error = ipsec_setspidx(m, &spidx,
433 (flag & IP_FORWARDING) ? 0 : 1);
434 if (*error != 0) {
435 DPRINTF(("%s: setpidx failed, dir %u flag %u\n",
436 __func__, dir, flag));
437 return (NULL);
438 }
439 spidx.dir = dir;
440
441 sp = KEY_ALLOCSP(&spidx, dir);
442 }
443 if (sp == NULL) /* No SP found, use system default. */
444 sp = KEY_ALLOCSP_DEFAULT();
445 IPSEC_ASSERT(sp != NULL, ("null SP"));
446 return (sp);
447 }
448
449 struct secpolicy *
ipsec4_checkpolicy(struct mbuf * m,u_int dir,u_int flag,int * error,struct inpcb * inp)450 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error,
451 struct inpcb *inp)
452 {
453 struct secpolicy *sp;
454
455 *error = 0;
456 if (inp == NULL)
457 sp = ipsec_getpolicybyaddr(m, dir, flag, error);
458 else
459 sp = ipsec_getpolicybysock(m, dir, inp, error);
460 if (sp == NULL) {
461 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error"));
462 IPSECSTAT_INC(ips_out_inval);
463 return (NULL);
464 }
465 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error));
466 switch (sp->policy) {
467 case IPSEC_POLICY_ENTRUST:
468 default:
469 printf("%s: invalid policy %u\n", __func__, sp->policy);
470 /* FALLTHROUGH */
471 case IPSEC_POLICY_DISCARD:
472 IPSECSTAT_INC(ips_out_polvio);
473 *error = -EINVAL; /* Packet is discarded by caller. */
474 break;
475 case IPSEC_POLICY_BYPASS:
476 case IPSEC_POLICY_NONE:
477 KEY_FREESP(&sp);
478 sp = NULL; /* NB: force NULL result. */
479 break;
480 case IPSEC_POLICY_IPSEC:
481 if (sp->req == NULL) /* Acquire a SA. */
482 *error = key_spdacquire(sp);
483 break;
484 }
485 if (*error != 0) {
486 KEY_FREESP(&sp);
487 sp = NULL;
488 }
489 return (sp);
490 }
491
492 static int
ipsec_setspidx_inpcb(struct mbuf * m,struct inpcb * inp)493 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp)
494 {
495 int error;
496
497 IPSEC_ASSERT(inp != NULL, ("null inp"));
498 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
499 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL,
500 ("null sp_in || sp_out"));
501
502 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1);
503 if (error == 0) {
504 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND;
505 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx;
506 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND;
507 } else {
508 bzero(&inp->inp_sp->sp_in->spidx,
509 sizeof (inp->inp_sp->sp_in->spidx));
510 bzero(&inp->inp_sp->sp_out->spidx,
511 sizeof (inp->inp_sp->sp_in->spidx));
512 }
513 return (error);
514 }
515
516 /*
517 * Configure security policy index (src/dst/proto/sport/dport)
518 * by looking at the content of mbuf.
519 * The caller is responsible for error recovery (like clearing up spidx).
520 */
521 static int
ipsec_setspidx(struct mbuf * m,struct secpolicyindex * spidx,int needport)522 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport)
523 {
524 struct ip *ip = NULL;
525 struct ip ipbuf;
526 u_int v;
527 struct mbuf *n;
528 int len;
529 int error;
530
531 IPSEC_ASSERT(m != NULL, ("null mbuf"));
532
533 /*
534 * Validate m->m_pkthdr.len. We see incorrect length if we
535 * mistakenly call this function with inconsistent mbuf chain
536 * (like 4.4BSD tcp/udp processing). XXX Should we panic here?
537 */
538 len = 0;
539 for (n = m; n; n = n->m_next)
540 len += n->m_len;
541 if (m->m_pkthdr.len != len) {
542 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
543 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n",
544 __func__, len, m->m_pkthdr.len));
545 return (EINVAL);
546 }
547
548 if (m->m_pkthdr.len < sizeof(struct ip)) {
549 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
550 printf("%s: pkthdr len(%d) too small (v4), ignored.\n",
551 __func__, m->m_pkthdr.len));
552 return (EINVAL);
553 }
554
555 if (m->m_len >= sizeof(*ip))
556 ip = mtod(m, struct ip *);
557 else {
558 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf);
559 ip = &ipbuf;
560 }
561 v = ip->ip_v;
562 switch (v) {
563 case 4:
564 error = ipsec4_setspidx_ipaddr(m, spidx);
565 if (error)
566 return (error);
567 ipsec4_get_ulp(m, spidx, needport);
568 return (0);
569 #ifdef INET6
570 case 6:
571 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) {
572 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
573 printf("%s: pkthdr len(%d) too small (v6), "
574 "ignored\n", __func__, m->m_pkthdr.len));
575 return (EINVAL);
576 }
577 error = ipsec6_setspidx_ipaddr(m, spidx);
578 if (error)
579 return (error);
580 ipsec6_get_ulp(m, spidx, needport);
581 return (0);
582 #endif
583 default:
584 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
585 printf("%s: " "unknown IP version %u, ignored.\n",
586 __func__, v));
587 return (EINVAL);
588 }
589 }
590
591 static void
ipsec4_get_ulp(struct mbuf * m,struct secpolicyindex * spidx,int needport)592 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
593 {
594 u_int8_t nxt;
595 int off;
596
597 /* Sanity check. */
598 IPSEC_ASSERT(m != NULL, ("null mbuf"));
599 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short"));
600
601 if (m->m_len >= sizeof (struct ip)) {
602 struct ip *ip = mtod(m, struct ip *);
603 if (ip->ip_off & htons(IP_MF | IP_OFFMASK))
604 goto done;
605 off = ip->ip_hl << 2;
606 nxt = ip->ip_p;
607 } else {
608 struct ip ih;
609
610 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih);
611 if (ih.ip_off & htons(IP_MF | IP_OFFMASK))
612 goto done;
613 off = ih.ip_hl << 2;
614 nxt = ih.ip_p;
615 }
616
617 while (off < m->m_pkthdr.len) {
618 struct ip6_ext ip6e;
619 struct tcphdr th;
620 struct udphdr uh;
621
622 switch (nxt) {
623 case IPPROTO_TCP:
624 spidx->ul_proto = nxt;
625 if (!needport)
626 goto done_proto;
627 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
628 goto done;
629 m_copydata(m, off, sizeof (th), (caddr_t) &th);
630 spidx->src.sin.sin_port = th.th_sport;
631 spidx->dst.sin.sin_port = th.th_dport;
632 return;
633 case IPPROTO_UDP:
634 spidx->ul_proto = nxt;
635 if (!needport)
636 goto done_proto;
637 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
638 goto done;
639 m_copydata(m, off, sizeof (uh), (caddr_t) &uh);
640 spidx->src.sin.sin_port = uh.uh_sport;
641 spidx->dst.sin.sin_port = uh.uh_dport;
642 return;
643 case IPPROTO_AH:
644 if (off + sizeof(ip6e) > m->m_pkthdr.len)
645 goto done;
646 /* XXX Sigh, this works but is totally bogus. */
647 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e);
648 off += (ip6e.ip6e_len + 2) << 2;
649 nxt = ip6e.ip6e_nxt;
650 break;
651 case IPPROTO_ICMP:
652 default:
653 /* XXX Intermediate headers??? */
654 spidx->ul_proto = nxt;
655 goto done_proto;
656 }
657 }
658 done:
659 spidx->ul_proto = IPSEC_ULPROTO_ANY;
660 done_proto:
661 spidx->src.sin.sin_port = IPSEC_PORT_ANY;
662 spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
663 }
664
665 /* Assumes that m is sane. */
666 static int
ipsec4_setspidx_ipaddr(struct mbuf * m,struct secpolicyindex * spidx)667 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
668 {
669 static const struct sockaddr_in template = {
670 sizeof (struct sockaddr_in),
671 AF_INET,
672 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 }
673 };
674
675 spidx->src.sin = template;
676 spidx->dst.sin = template;
677
678 if (m->m_len < sizeof (struct ip)) {
679 m_copydata(m, offsetof(struct ip, ip_src),
680 sizeof (struct in_addr),
681 (caddr_t) &spidx->src.sin.sin_addr);
682 m_copydata(m, offsetof(struct ip, ip_dst),
683 sizeof (struct in_addr),
684 (caddr_t) &spidx->dst.sin.sin_addr);
685 } else {
686 struct ip *ip = mtod(m, struct ip *);
687 spidx->src.sin.sin_addr = ip->ip_src;
688 spidx->dst.sin.sin_addr = ip->ip_dst;
689 }
690
691 spidx->prefs = sizeof(struct in_addr) << 3;
692 spidx->prefd = sizeof(struct in_addr) << 3;
693
694 return (0);
695 }
696
697 #ifdef INET6
698 static void
ipsec6_get_ulp(struct mbuf * m,struct secpolicyindex * spidx,int needport)699 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
700 {
701 int off, nxt;
702 struct tcphdr th;
703 struct udphdr uh;
704 struct icmp6_hdr ih;
705
706 /* Sanity check. */
707 if (m == NULL)
708 panic("%s: NULL pointer was passed.\n", __func__);
709
710 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
711 printf("%s:\n", __func__); kdebug_mbuf(m));
712
713 /* Set default. */
714 spidx->ul_proto = IPSEC_ULPROTO_ANY;
715 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY;
716 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY;
717
718 nxt = -1;
719 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
720 if (off < 0 || m->m_pkthdr.len < off)
721 return;
722
723 switch (nxt) {
724 case IPPROTO_TCP:
725 spidx->ul_proto = nxt;
726 if (!needport)
727 break;
728 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
729 break;
730 m_copydata(m, off, sizeof(th), (caddr_t)&th);
731 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport;
732 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport;
733 break;
734 case IPPROTO_UDP:
735 spidx->ul_proto = nxt;
736 if (!needport)
737 break;
738 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
739 break;
740 m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
741 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport;
742 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport;
743 break;
744 case IPPROTO_ICMPV6:
745 spidx->ul_proto = nxt;
746 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
747 break;
748 m_copydata(m, off, sizeof(ih), (caddr_t)&ih);
749 ((struct sockaddr_in6 *)&spidx->src)->sin6_port =
750 htons((uint16_t)ih.icmp6_type);
751 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port =
752 htons((uint16_t)ih.icmp6_code);
753 break;
754 default:
755 /* XXX Intermediate headers??? */
756 spidx->ul_proto = nxt;
757 break;
758 }
759 }
760
761 /* Assumes that m is sane. */
762 static int
ipsec6_setspidx_ipaddr(struct mbuf * m,struct secpolicyindex * spidx)763 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
764 {
765 struct ip6_hdr *ip6 = NULL;
766 struct ip6_hdr ip6buf;
767 struct sockaddr_in6 *sin6;
768
769 if (m->m_len >= sizeof(*ip6))
770 ip6 = mtod(m, struct ip6_hdr *);
771 else {
772 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf);
773 ip6 = &ip6buf;
774 }
775
776 sin6 = (struct sockaddr_in6 *)&spidx->src;
777 bzero(sin6, sizeof(*sin6));
778 sin6->sin6_family = AF_INET6;
779 sin6->sin6_len = sizeof(struct sockaddr_in6);
780 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src));
781 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
782 sin6->sin6_addr.s6_addr16[1] = 0;
783 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]);
784 }
785 spidx->prefs = sizeof(struct in6_addr) << 3;
786
787 sin6 = (struct sockaddr_in6 *)&spidx->dst;
788 bzero(sin6, sizeof(*sin6));
789 sin6->sin6_family = AF_INET6;
790 sin6->sin6_len = sizeof(struct sockaddr_in6);
791 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst));
792 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
793 sin6->sin6_addr.s6_addr16[1] = 0;
794 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
795 }
796 spidx->prefd = sizeof(struct in6_addr) << 3;
797
798 return (0);
799 }
800 #endif
801
802 static void
ipsec_delpcbpolicy(struct inpcbpolicy * p)803 ipsec_delpcbpolicy(struct inpcbpolicy *p)
804 {
805
806 free(p, M_IPSEC_INPCB);
807 }
808
809 /* Initialize policy in PCB. */
810 int
ipsec_init_policy(struct socket * so,struct inpcbpolicy ** pcb_sp)811 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp)
812 {
813 struct inpcbpolicy *new;
814
815 /* Sanity check. */
816 if (so == NULL || pcb_sp == NULL)
817 panic("%s: NULL pointer was passed.\n", __func__);
818
819 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy),
820 M_IPSEC_INPCB, M_NOWAIT|M_ZERO);
821 if (new == NULL) {
822 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
823 return (ENOBUFS);
824 }
825
826 new->priv = IPSEC_IS_PRIVILEGED_SO(so);
827
828 if ((new->sp_in = KEY_NEWSP()) == NULL) {
829 ipsec_delpcbpolicy(new);
830 return (ENOBUFS);
831 }
832 new->sp_in->state = IPSEC_SPSTATE_ALIVE;
833 new->sp_in->policy = IPSEC_POLICY_ENTRUST;
834
835 if ((new->sp_out = KEY_NEWSP()) == NULL) {
836 KEY_FREESP(&new->sp_in);
837 ipsec_delpcbpolicy(new);
838 return (ENOBUFS);
839 }
840 new->sp_out->state = IPSEC_SPSTATE_ALIVE;
841 new->sp_out->policy = IPSEC_POLICY_ENTRUST;
842
843 *pcb_sp = new;
844
845 return (0);
846 }
847
848 /* Copy old IPsec policy into new. */
849 int
ipsec_copy_policy(struct inpcbpolicy * old,struct inpcbpolicy * new)850 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new)
851 {
852 struct secpolicy *sp;
853
854 sp = ipsec_deepcopy_policy(old->sp_in);
855 if (sp) {
856 KEY_FREESP(&new->sp_in);
857 new->sp_in = sp;
858 } else
859 return (ENOBUFS);
860
861 sp = ipsec_deepcopy_policy(old->sp_out);
862 if (sp) {
863 KEY_FREESP(&new->sp_out);
864 new->sp_out = sp;
865 } else
866 return (ENOBUFS);
867
868 new->priv = old->priv;
869
870 return (0);
871 }
872
873 struct ipsecrequest *
ipsec_newisr(void)874 ipsec_newisr(void)
875 {
876 struct ipsecrequest *p;
877
878 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO);
879 if (p != NULL)
880 IPSECREQUEST_LOCK_INIT(p);
881 return (p);
882 }
883
884 void
ipsec_delisr(struct ipsecrequest * p)885 ipsec_delisr(struct ipsecrequest *p)
886 {
887
888 IPSECREQUEST_LOCK_DESTROY(p);
889 free(p, M_IPSEC_SR);
890 }
891
892 /* Deep-copy a policy in PCB. */
893 static struct secpolicy *
ipsec_deepcopy_policy(struct secpolicy * src)894 ipsec_deepcopy_policy(struct secpolicy *src)
895 {
896 struct ipsecrequest *newchain = NULL;
897 struct ipsecrequest *p;
898 struct ipsecrequest **q;
899 struct ipsecrequest *r;
900 struct secpolicy *dst;
901
902 if (src == NULL)
903 return (NULL);
904 dst = KEY_NEWSP();
905 if (dst == NULL)
906 return (NULL);
907
908 /*
909 * Deep-copy IPsec request chain. This is required since struct
910 * ipsecrequest is not reference counted.
911 */
912 q = &newchain;
913 for (p = src->req; p; p = p->next) {
914 *q = ipsec_newisr();
915 if (*q == NULL)
916 goto fail;
917 (*q)->saidx.proto = p->saidx.proto;
918 (*q)->saidx.mode = p->saidx.mode;
919 (*q)->level = p->level;
920 (*q)->saidx.reqid = p->saidx.reqid;
921
922 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src));
923 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst));
924
925 (*q)->sp = dst;
926
927 q = &((*q)->next);
928 }
929
930 dst->req = newchain;
931 dst->state = src->state;
932 dst->policy = src->policy;
933 /* Do not touch the refcnt fields. */
934
935 return (dst);
936
937 fail:
938 for (p = newchain; p; p = r) {
939 r = p->next;
940 ipsec_delisr(p);
941 p = NULL;
942 }
943 KEY_FREESP(&dst);
944 return (NULL);
945 }
946
947 /* Set policy and IPsec request if present. */
948 static int
ipsec_set_policy_internal(struct secpolicy ** pcb_sp,int optname,caddr_t request,size_t len,struct ucred * cred)949 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname,
950 caddr_t request, size_t len, struct ucred *cred)
951 {
952 struct sadb_x_policy *xpl;
953 struct secpolicy *newsp = NULL;
954 int error;
955
956 /* Sanity check. */
957 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL)
958 return (EINVAL);
959 if (len < sizeof(*xpl))
960 return (EINVAL);
961 xpl = (struct sadb_x_policy *)request;
962
963 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
964 printf("%s: passed policy\n", __func__);
965 kdebug_sadb_x_policy((struct sadb_ext *)xpl));
966
967 /* Check policy type. */
968 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */
969 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD
970 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE)
971 return (EINVAL);
972
973 /* Check privileged socket. */
974 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) {
975 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0);
976 if (error)
977 return (EACCES);
978 }
979
980 /* Allocating new SP entry. */
981 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL)
982 return (error);
983
984 newsp->state = IPSEC_SPSTATE_ALIVE;
985
986 /* Clear old SP and set new SP. */
987 KEY_FREESP(pcb_sp);
988 *pcb_sp = newsp;
989 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
990 printf("%s: new policy\n", __func__);
991 kdebug_secpolicy(newsp));
992
993 return (0);
994 }
995
996 int
ipsec_set_policy(struct inpcb * inp,int optname,caddr_t request,size_t len,struct ucred * cred)997 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request,
998 size_t len, struct ucred *cred)
999 {
1000 struct sadb_x_policy *xpl;
1001 struct secpolicy **pcb_sp;
1002
1003 /* Sanity check. */
1004 if (inp == NULL || request == NULL)
1005 return (EINVAL);
1006 if (len < sizeof(*xpl))
1007 return (EINVAL);
1008 xpl = (struct sadb_x_policy *)request;
1009
1010 /* Select direction. */
1011 switch (xpl->sadb_x_policy_dir) {
1012 case IPSEC_DIR_INBOUND:
1013 pcb_sp = &inp->inp_sp->sp_in;
1014 break;
1015 case IPSEC_DIR_OUTBOUND:
1016 pcb_sp = &inp->inp_sp->sp_out;
1017 break;
1018 default:
1019 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1020 xpl->sadb_x_policy_dir));
1021 return (EINVAL);
1022 }
1023
1024 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred));
1025 }
1026
1027 int
ipsec_get_policy(struct inpcb * inp,caddr_t request,size_t len,struct mbuf ** mp)1028 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len,
1029 struct mbuf **mp)
1030 {
1031 struct sadb_x_policy *xpl;
1032 struct secpolicy *pcb_sp;
1033
1034 /* Sanity check. */
1035 if (inp == NULL || request == NULL || mp == NULL)
1036 return (EINVAL);
1037 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
1038 if (len < sizeof(*xpl))
1039 return (EINVAL);
1040 xpl = (struct sadb_x_policy *)request;
1041
1042 /* Select direction. */
1043 switch (xpl->sadb_x_policy_dir) {
1044 case IPSEC_DIR_INBOUND:
1045 pcb_sp = inp->inp_sp->sp_in;
1046 break;
1047 case IPSEC_DIR_OUTBOUND:
1048 pcb_sp = inp->inp_sp->sp_out;
1049 break;
1050 default:
1051 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1052 xpl->sadb_x_policy_dir));
1053 return (EINVAL);
1054 }
1055
1056 /* Sanity check. Should be an IPSEC_ASSERT. */
1057 if (pcb_sp == NULL)
1058 return (EINVAL);
1059
1060 *mp = key_sp2msg(pcb_sp);
1061 if (!*mp) {
1062 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
1063 return (ENOBUFS);
1064 }
1065
1066 (*mp)->m_type = MT_DATA;
1067 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1068 printf("%s:\n", __func__); kdebug_mbuf(*mp));
1069
1070 return (0);
1071 }
1072
1073 /* Delete policy in PCB. */
1074 int
ipsec_delete_pcbpolicy(struct inpcb * inp)1075 ipsec_delete_pcbpolicy(struct inpcb *inp)
1076 {
1077 IPSEC_ASSERT(inp != NULL, ("null inp"));
1078
1079 if (inp->inp_sp == NULL)
1080 return (0);
1081
1082 if (inp->inp_sp->sp_in != NULL)
1083 KEY_FREESP(&inp->inp_sp->sp_in);
1084
1085 if (inp->inp_sp->sp_out != NULL)
1086 KEY_FREESP(&inp->inp_sp->sp_out);
1087
1088 ipsec_delpcbpolicy(inp->inp_sp);
1089 inp->inp_sp = NULL;
1090
1091 return (0);
1092 }
1093
1094 /*
1095 * Return current level.
1096 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
1097 */
1098 u_int
ipsec_get_reqlevel(struct ipsecrequest * isr)1099 ipsec_get_reqlevel(struct ipsecrequest *isr)
1100 {
1101 u_int level = 0;
1102 u_int esp_trans_deflev, esp_net_deflev;
1103 u_int ah_trans_deflev, ah_net_deflev;
1104
1105 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument"));
1106 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family,
1107 ("af family mismatch, src %u, dst %u",
1108 isr->sp->spidx.src.sa.sa_family,
1109 isr->sp->spidx.dst.sa.sa_family));
1110
1111 /* XXX Note that we have ipseclog() expanded here - code sync issue. */
1112 #define IPSEC_CHECK_DEFAULT(lev) \
1113 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \
1114 && (lev) != IPSEC_LEVEL_UNIQUE) \
1115 ? (V_ipsec_debug \
1116 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\
1117 (lev), IPSEC_LEVEL_REQUIRE) \
1118 : 0), \
1119 (lev) = IPSEC_LEVEL_REQUIRE, \
1120 (lev) \
1121 : (lev))
1122
1123 /* Set default level. */
1124 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) {
1125 #ifdef INET
1126 case AF_INET:
1127 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev);
1128 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev);
1129 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev);
1130 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev);
1131 break;
1132 #endif
1133 #ifdef INET6
1134 case AF_INET6:
1135 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev);
1136 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev);
1137 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev);
1138 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev);
1139 break;
1140 #endif /* INET6 */
1141 default:
1142 panic("%s: unknown af %u",
1143 __func__, isr->sp->spidx.src.sa.sa_family);
1144 }
1145
1146 #undef IPSEC_CHECK_DEFAULT
1147
1148 /* Set level. */
1149 switch (isr->level) {
1150 case IPSEC_LEVEL_DEFAULT:
1151 switch (isr->saidx.proto) {
1152 case IPPROTO_ESP:
1153 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1154 level = esp_net_deflev;
1155 else
1156 level = esp_trans_deflev;
1157 break;
1158 case IPPROTO_AH:
1159 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1160 level = ah_net_deflev;
1161 else
1162 level = ah_trans_deflev;
1163 break;
1164 case IPPROTO_IPCOMP:
1165 /*
1166 * We don't really care, as IPcomp document says that
1167 * we shouldn't compress small packets.
1168 */
1169 level = IPSEC_LEVEL_USE;
1170 break;
1171 default:
1172 panic("%s: Illegal protocol defined %u\n", __func__,
1173 isr->saidx.proto);
1174 }
1175 break;
1176
1177 case IPSEC_LEVEL_USE:
1178 case IPSEC_LEVEL_REQUIRE:
1179 level = isr->level;
1180 break;
1181 case IPSEC_LEVEL_UNIQUE:
1182 level = IPSEC_LEVEL_REQUIRE;
1183 break;
1184
1185 default:
1186 panic("%s: Illegal IPsec level %u\n", __func__, isr->level);
1187 }
1188
1189 return (level);
1190 }
1191
1192 /*
1193 * Check security policy requirements against the actual
1194 * packet contents. Return one if the packet should be
1195 * reject as "invalid"; otherwiser return zero to have the
1196 * packet treated as "valid".
1197 *
1198 * OUT:
1199 * 0: valid
1200 * 1: invalid
1201 */
1202 int
ipsec_in_reject(struct secpolicy * sp,struct mbuf * m)1203 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m)
1204 {
1205 struct ipsecrequest *isr;
1206 int need_auth;
1207
1208 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1209 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1210
1211 /* Check policy. */
1212 switch (sp->policy) {
1213 case IPSEC_POLICY_DISCARD:
1214 return (1);
1215 case IPSEC_POLICY_BYPASS:
1216 case IPSEC_POLICY_NONE:
1217 return (0);
1218 }
1219
1220 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1221 ("invalid policy %u", sp->policy));
1222
1223 /* XXX Should compare policy against IPsec header history. */
1224
1225 need_auth = 0;
1226 for (isr = sp->req; isr != NULL; isr = isr->next) {
1227 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE)
1228 continue;
1229 switch (isr->saidx.proto) {
1230 case IPPROTO_ESP:
1231 if ((m->m_flags & M_DECRYPTED) == 0) {
1232 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1233 printf("%s: ESP m_flags:%x\n", __func__,
1234 m->m_flags));
1235 return (1);
1236 }
1237
1238 if (!need_auth &&
1239 isr->sav != NULL &&
1240 isr->sav->tdb_authalgxform != NULL &&
1241 (m->m_flags & M_AUTHIPDGM) == 0) {
1242 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1243 printf("%s: ESP/AH m_flags:%x\n", __func__,
1244 m->m_flags));
1245 return (1);
1246 }
1247 break;
1248 case IPPROTO_AH:
1249 need_auth = 1;
1250 if ((m->m_flags & M_AUTHIPHDR) == 0) {
1251 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1252 printf("%s: AH m_flags:%x\n", __func__,
1253 m->m_flags));
1254 return (1);
1255 }
1256 break;
1257 case IPPROTO_IPCOMP:
1258 /*
1259 * We don't really care, as IPcomp document
1260 * says that we shouldn't compress small
1261 * packets. IPComp policy should always be
1262 * treated as being in "use" level.
1263 */
1264 break;
1265 }
1266 }
1267 return (0); /* Valid. */
1268 }
1269
1270 static int
ipsec46_in_reject(struct mbuf * m,struct inpcb * inp)1271 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp)
1272 {
1273 struct secpolicy *sp;
1274 int error;
1275 int result;
1276
1277 if (!key_havesp(IPSEC_DIR_INBOUND))
1278 return 0;
1279
1280 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1281
1282 /*
1283 * Get SP for this packet.
1284 * When we are called from ip_forward(), we call
1285 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1286 */
1287 if (inp == NULL)
1288 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error);
1289 else
1290 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error);
1291
1292 if (sp != NULL) {
1293 result = ipsec_in_reject(sp, m);
1294 KEY_FREESP(&sp);
1295 } else {
1296 result = 0; /* XXX Should be panic?
1297 * -> No, there may be error. */
1298 }
1299 return (result);
1300 }
1301
1302 /*
1303 * Check AH/ESP integrity.
1304 * This function is called from tcp_input(), udp_input(),
1305 * and {ah,esp}4_input for tunnel mode.
1306 */
1307 int
ipsec4_in_reject(struct mbuf * m,struct inpcb * inp)1308 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp)
1309 {
1310 int result;
1311
1312 result = ipsec46_in_reject(m, inp);
1313 if (result)
1314 IPSECSTAT_INC(ips_in_polvio);
1315
1316 return (result);
1317 }
1318
1319 #ifdef INET6
1320 /*
1321 * Check AH/ESP integrity.
1322 * This function is called from tcp6_input(), udp6_input(),
1323 * and {ah,esp}6_input for tunnel mode.
1324 */
1325 int
ipsec6_in_reject(struct mbuf * m,struct inpcb * inp)1326 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp)
1327 {
1328 int result;
1329
1330 result = ipsec46_in_reject(m, inp);
1331 if (result)
1332 IPSEC6STAT_INC(ips_in_polvio);
1333
1334 return (result);
1335 }
1336 #endif
1337
1338 /*
1339 * Compute the byte size to be occupied by IPsec header.
1340 * In case it is tunnelled, it includes the size of outer IP header.
1341 * NOTE: SP passed is freed in this function.
1342 */
1343 static size_t
ipsec_hdrsiz_internal(struct secpolicy * sp)1344 ipsec_hdrsiz_internal(struct secpolicy *sp)
1345 {
1346 struct ipsecrequest *isr;
1347 size_t size;
1348
1349 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1350 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1351
1352 switch (sp->policy) {
1353 case IPSEC_POLICY_DISCARD:
1354 case IPSEC_POLICY_BYPASS:
1355 case IPSEC_POLICY_NONE:
1356 return (0);
1357 }
1358
1359 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1360 ("invalid policy %u", sp->policy));
1361
1362 size = 0;
1363 for (isr = sp->req; isr != NULL; isr = isr->next) {
1364 size_t clen = 0;
1365
1366 switch (isr->saidx.proto) {
1367 case IPPROTO_ESP:
1368 clen = esp_hdrsiz(isr->sav);
1369 break;
1370 case IPPROTO_AH:
1371 clen = ah_hdrsiz(isr->sav);
1372 break;
1373 case IPPROTO_IPCOMP:
1374 clen = sizeof(struct ipcomp);
1375 break;
1376 }
1377
1378 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
1379 switch (isr->saidx.dst.sa.sa_family) {
1380 case AF_INET:
1381 clen += sizeof(struct ip);
1382 break;
1383 #ifdef INET6
1384 case AF_INET6:
1385 clen += sizeof(struct ip6_hdr);
1386 break;
1387 #endif
1388 default:
1389 ipseclog((LOG_ERR, "%s: unknown AF %d in "
1390 "IPsec tunnel SA\n", __func__,
1391 ((struct sockaddr *)&isr->saidx.dst)->sa_family));
1392 break;
1393 }
1394 }
1395 size += clen;
1396 }
1397
1398 return (size);
1399 }
1400
1401 /*
1402 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(),
1403 * disabled ip6_ipsec_mtu() and ip6_forward().
1404 */
1405 size_t
ipsec_hdrsiz(struct mbuf * m,u_int dir,struct inpcb * inp)1406 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp)
1407 {
1408 struct secpolicy *sp;
1409 int error;
1410 size_t size;
1411
1412 if (!key_havesp(dir))
1413 return 0;
1414
1415 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1416
1417 /* Get SP for this packet.
1418 * When we are called from ip_forward(), we call
1419 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1420 */
1421 if (inp == NULL)
1422 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error);
1423 else
1424 sp = ipsec_getpolicybysock(m, dir, inp, &error);
1425
1426 if (sp != NULL) {
1427 size = ipsec_hdrsiz_internal(sp);
1428 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1429 printf("%s: size:%lu.\n", __func__,
1430 (unsigned long)size));
1431
1432 KEY_FREESP(&sp);
1433 } else {
1434 size = 0; /* XXX Should be panic?
1435 * -> No, we are called w/o knowing if
1436 * IPsec processing is needed. */
1437 }
1438 return (size);
1439 }
1440
1441 /*
1442 * Check the variable replay window.
1443 * ipsec_chkreplay() performs replay check before ICV verification.
1444 * ipsec_updatereplay() updates replay bitmap. This must be called after
1445 * ICV verification (it also performs replay check, which is usually done
1446 * beforehand).
1447 * 0 (zero) is returned if packet disallowed, 1 if packet permitted.
1448 *
1449 * Based on RFC 2401.
1450 */
1451 int
ipsec_chkreplay(u_int32_t seq,struct secasvar * sav)1452 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav)
1453 {
1454 const struct secreplay *replay;
1455 u_int32_t diff;
1456 int fr;
1457 u_int32_t wsizeb; /* Constant: bits of window size. */
1458 int frlast; /* Constant: last frame. */
1459
1460 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1461 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1462
1463 replay = sav->replay;
1464
1465 if (replay->wsize == 0)
1466 return (1); /* No need to check replay. */
1467
1468 /* Constant. */
1469 frlast = replay->wsize - 1;
1470 wsizeb = replay->wsize << 3;
1471
1472 /* Sequence number of 0 is invalid. */
1473 if (seq == 0)
1474 return (0);
1475
1476 /* First time is always okay. */
1477 if (replay->count == 0)
1478 return (1);
1479
1480 if (seq > replay->lastseq) {
1481 /* Larger sequences are okay. */
1482 return (1);
1483 } else {
1484 /* seq is equal or less than lastseq. */
1485 diff = replay->lastseq - seq;
1486
1487 /* Over range to check, i.e. too old or wrapped. */
1488 if (diff >= wsizeb)
1489 return (0);
1490
1491 fr = frlast - diff / 8;
1492
1493 /* This packet already seen? */
1494 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1495 return (0);
1496
1497 /* Out of order but good. */
1498 return (1);
1499 }
1500 }
1501
1502 /*
1503 * Check replay counter whether to update or not.
1504 * OUT: 0: OK
1505 * 1: NG
1506 */
1507 int
ipsec_updatereplay(u_int32_t seq,struct secasvar * sav)1508 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav)
1509 {
1510 struct secreplay *replay;
1511 u_int32_t diff;
1512 int fr;
1513 u_int32_t wsizeb; /* Constant: bits of window size. */
1514 int frlast; /* Constant: last frame. */
1515
1516 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1517 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1518
1519 replay = sav->replay;
1520
1521 if (replay->wsize == 0)
1522 goto ok; /* No need to check replay. */
1523
1524 /* Constant. */
1525 frlast = replay->wsize - 1;
1526 wsizeb = replay->wsize << 3;
1527
1528 /* Sequence number of 0 is invalid. */
1529 if (seq == 0)
1530 return (1);
1531
1532 /* First time. */
1533 if (replay->count == 0) {
1534 replay->lastseq = seq;
1535 bzero(replay->bitmap, replay->wsize);
1536 (replay->bitmap)[frlast] = 1;
1537 goto ok;
1538 }
1539
1540 if (seq > replay->lastseq) {
1541 /* seq is larger than lastseq. */
1542 diff = seq - replay->lastseq;
1543
1544 /* New larger sequence number. */
1545 if (diff < wsizeb) {
1546 /* In window. */
1547 /* Set bit for this packet. */
1548 vshiftl(replay->bitmap, diff, replay->wsize);
1549 (replay->bitmap)[frlast] |= 1;
1550 } else {
1551 /* This packet has a "way larger". */
1552 bzero(replay->bitmap, replay->wsize);
1553 (replay->bitmap)[frlast] = 1;
1554 }
1555 replay->lastseq = seq;
1556
1557 /* Larger is good. */
1558 } else {
1559 /* seq is equal or less than lastseq. */
1560 diff = replay->lastseq - seq;
1561
1562 /* Over range to check, i.e. too old or wrapped. */
1563 if (diff >= wsizeb)
1564 return (1);
1565
1566 fr = frlast - diff / 8;
1567
1568 /* This packet already seen? */
1569 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1570 return (1);
1571
1572 /* Mark as seen. */
1573 (replay->bitmap)[fr] |= (1 << (diff % 8));
1574
1575 /* Out of order but good. */
1576 }
1577
1578 ok:
1579 if (replay->count == ~0) {
1580
1581 /* Set overflow flag. */
1582 replay->overflow++;
1583
1584 /* Don't increment, no more packets accepted. */
1585 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0)
1586 return (1);
1587
1588 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n",
1589 __func__, replay->overflow, ipsec_logsastr(sav)));
1590 }
1591
1592 replay->count++;
1593
1594 return (0);
1595 }
1596
1597 /*
1598 * Shift variable length buffer to left.
1599 * IN: bitmap: pointer to the buffer
1600 * nbit: the number of to shift.
1601 * wsize: buffer size (bytes).
1602 */
1603 static void
vshiftl(unsigned char * bitmap,int nbit,int wsize)1604 vshiftl(unsigned char *bitmap, int nbit, int wsize)
1605 {
1606 int s, j, i;
1607 unsigned char over;
1608
1609 for (j = 0; j < nbit; j += 8) {
1610 s = (nbit - j < 8) ? (nbit - j): 8;
1611 bitmap[0] <<= s;
1612 for (i = 1; i < wsize; i++) {
1613 over = (bitmap[i] >> (8 - s));
1614 bitmap[i] <<= s;
1615 bitmap[i-1] |= over;
1616 }
1617 }
1618 }
1619
1620 #ifdef INET
1621 /* Return a printable string for the IPv4 address. */
1622 static char *
inet_ntoa4(struct in_addr ina)1623 inet_ntoa4(struct in_addr ina)
1624 {
1625 static char buf[4][4 * sizeof "123" + 4];
1626 unsigned char *ucp = (unsigned char *) &ina;
1627 static int i = 3;
1628
1629 /* XXX-BZ Returns static buffer. */
1630 i = (i + 1) % 4;
1631 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff,
1632 ucp[2] & 0xff, ucp[3] & 0xff);
1633 return (buf[i]);
1634 }
1635 #endif
1636
1637 /* Return a printable string for the address. */
1638 char *
ipsec_address(union sockaddr_union * sa)1639 ipsec_address(union sockaddr_union* sa)
1640 {
1641 #ifdef INET6
1642 char ip6buf[INET6_ADDRSTRLEN];
1643 #endif
1644
1645 switch (sa->sa.sa_family) {
1646 #ifdef INET
1647 case AF_INET:
1648 return (inet_ntoa4(sa->sin.sin_addr));
1649 #endif /* INET */
1650 #ifdef INET6
1651 case AF_INET6:
1652 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr));
1653 #endif /* INET6 */
1654 default:
1655 return ("(unknown address family)");
1656 }
1657 }
1658
1659 const char *
ipsec_logsastr(struct secasvar * sav)1660 ipsec_logsastr(struct secasvar *sav)
1661 {
1662 static char buf[256];
1663 char *p;
1664 struct secasindex *saidx = &sav->sah->saidx;
1665
1666 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family,
1667 ("address family mismatch"));
1668
1669 p = buf;
1670 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi));
1671 while (p && *p)
1672 p++;
1673 /* NB: only use ipsec_address on one address at a time. */
1674 snprintf(p, sizeof (buf) - (p - buf), "src=%s ",
1675 ipsec_address(&saidx->src));
1676 while (p && *p)
1677 p++;
1678 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)",
1679 ipsec_address(&saidx->dst));
1680
1681 return (buf);
1682 }
1683
1684 void
ipsec_dumpmbuf(struct mbuf * m)1685 ipsec_dumpmbuf(struct mbuf *m)
1686 {
1687 int totlen;
1688 int i;
1689 u_char *p;
1690
1691 totlen = 0;
1692 printf("---\n");
1693 while (m) {
1694 p = mtod(m, u_char *);
1695 for (i = 0; i < m->m_len; i++) {
1696 printf("%02x ", p[i]);
1697 totlen++;
1698 if (totlen % 16 == 0)
1699 printf("\n");
1700 }
1701 m = m->m_next;
1702 }
1703 if (totlen % 16 != 0)
1704 printf("\n");
1705 printf("---\n");
1706 }
1707
1708 static void
ipsec_init(const void * unused __unused)1709 ipsec_init(const void *unused __unused)
1710 {
1711
1712 SECPOLICY_LOCK_INIT(&V_ip4_def_policy);
1713 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */
1714 }
1715 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init,
1716 NULL);
1717
1718
1719 /* XXX This stuff doesn't belong here... */
1720
1721 static struct xformsw* xforms = NULL;
1722
1723 /*
1724 * Register a transform; typically at system startup.
1725 */
1726 void
xform_register(struct xformsw * xsp)1727 xform_register(struct xformsw* xsp)
1728 {
1729
1730 xsp->xf_next = xforms;
1731 xforms = xsp;
1732 }
1733
1734 /*
1735 * Initialize transform support in an sav.
1736 */
1737 int
xform_init(struct secasvar * sav,int xftype)1738 xform_init(struct secasvar *sav, int xftype)
1739 {
1740 struct xformsw *xsp;
1741
1742 if (sav->tdb_xform != NULL) /* Previously initialized. */
1743 return (0);
1744 for (xsp = xforms; xsp; xsp = xsp->xf_next)
1745 if (xsp->xf_type == xftype)
1746 return ((*xsp->xf_init)(sav, xsp));
1747 return (EINVAL);
1748 }
1749