sys/netinet6/esp_output.c

   1 /*      $FreeBSD: src/sys/netinet6/esp_output.c,v 1.1.2.4 2003/05/06 06:46:58 suz Exp $ */
   2 /*      $DragonFly: src/sys/netinet6/esp_output.c,v 1.9 2006/10/24 06:18:42 hsu Exp $   */
   3 /*      $KAME: esp_output.c,v 1.44 2001/07/26 06:53:15 jinmei Exp $     */
   4
   5 /*
   6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "opt_inet.h"
  35 #include "opt_inet6.h"
  36
  37 /*
  38  * RFC1827/2406 Encapsulated Security Payload.
  39  */
  40
  41 #include <sys/param.h>
  42 #include <sys/systm.h>
  43 #include <sys/mbuf.h>
  44 #include <sys/domain.h>
  45 #include <sys/protosw.h>
  46 #include <sys/socket.h>
  47 #include <sys/socketvar.h>
  48 #include <sys/errno.h>
  49 #include <sys/time.h>
  50 #include <sys/syslog.h>
  51
  52 #include <net/if.h>
  53 #include <net/route.h>
  54
  55 #include <netinet/in.h>
  56 #include <netinet/in_systm.h>
  57 #include <netinet/ip.h>
  58 #include <netinet/in_var.h>
  59
  60 #ifdef INET6
  61 #include <netinet/ip6.h>
  62 #include <netinet6/ip6_var.h>
  63 #include <netinet/icmp6.h>
  64 #endif
  65
  66 #include <netinet6/ipsec.h>
  67 #ifdef INET6
  68 #include <netinet6/ipsec6.h>
  69 #endif
  70 #include <netinet6/ah.h>
  71 #ifdef INET6
  72 #include <netinet6/ah6.h>
  73 #endif
  74 #include <netinet6/esp.h>
  75 #ifdef INET6
  76 #include <netinet6/esp6.h>
  77 #endif
  78 #include <netproto/key/key.h>
  79 #include <netproto/key/keydb.h>
  80
  81 #include <net/net_osdep.h>
  82
  83 static int esp_output (struct mbuf *, u_char *, struct mbuf *,
  84         struct ipsecrequest *, int);
  85
  86 /*
  87  * compute ESP header size.
  88  */
  89 size_t
  90 esp_hdrsiz(struct ipsecrequest *isr)
  91 {
  92         struct secasvar *sav;
  93         const struct esp_algorithm *algo;
  94         const struct ah_algorithm *aalgo;
  95         size_t ivlen;
  96         size_t authlen;
  97         size_t hdrsiz;
  98
  99         /* sanity check */
 100         if (isr == NULL)
 101                 panic("esp_hdrsiz: NULL was passed.");
 102
 103         sav = isr->sav;
 104
 105         if (isr->saidx.proto != IPPROTO_ESP)
 106                 panic("unsupported mode passed to esp_hdrsiz");
 107
 108         if (sav == NULL)
 109                 goto estimate;
 110         if (sav->state != SADB_SASTATE_MATURE &&
 111             sav->state != SADB_SASTATE_DYING)
 112                 goto estimate;
 113
 114         /* we need transport mode ESP. */
 115         algo = esp_algorithm_lookup(sav->alg_enc);
 116         if (!algo)
 117                 goto estimate;
 118         ivlen = sav->ivlen;
 119         if (ivlen < 0)
 120                 goto estimate;
 121
 122         /*
 123          * XXX
 124          * right now we don't calcurate the padding size.  simply
 125          * treat the padding size as constant, for simplicity.
 126          *
 127          * XXX variable size padding support
 128          */
 129         if (sav->flags & SADB_X_EXT_OLD) {
 130                 /* RFC 1827 */
 131                 hdrsiz = sizeof(struct esp) + ivlen + 9;
 132         } else {
 133                 /* RFC 2406 */
 134                 aalgo = ah_algorithm_lookup(sav->alg_auth);
 135                 if (aalgo && sav->replay && sav->key_auth)
 136                         authlen = (aalgo->sumsiz)(sav);
 137                 else
 138                         authlen = 0;
 139                 hdrsiz = sizeof(struct newesp) + ivlen + 9 + authlen;
 140         }
 141
 142         return hdrsiz;
 143
 144 estimate:
 145         /*
 146          * ASSUMING:
 147          *      sizeof(struct newesp) > sizeof(struct esp).
 148          *      esp_max_ivlen() = max ivlen for CBC mode
 149          *      9 = (maximum padding length without random padding length)
 150          *         + (Pad Length field) + (Next Header field).
 151          *      16 = maximum ICV we support.
 152          */
 153         return sizeof(struct newesp) + esp_max_ivlen() + 9 + 16;
 154 }
 155
 156 /*
 157  * Modify the packet so that the payload is encrypted.
 158  * The mbuf (m) must start with IPv4 or IPv6 header.
 159  * On failure, free the given mbuf and return NULL.
 160  *
 161  * on invocation:
 162  *      m   nexthdrp md
 163  *      v   v        v
 164  *      IP ......... payload
 165  * during the encryption:
 166  *      m   nexthdrp mprev md
 167  *      v   v        v     v
 168  *      IP ............... esp iv payload pad padlen nxthdr
 169  *                         <--><-><------><--------------->
 170  *                         esplen plen    extendsiz
 171  *                             ivlen
 172  *                         <-----> esphlen
 173  *      <-> hlen
 174  *      <-----------------> espoff
 175  */
 176 static int
 177 esp_output(struct mbuf *m, u_char *nexthdrp, struct mbuf *md,
 178            struct ipsecrequest *isr, int af)
 179 {
 180         struct mbuf *n;
 181         struct mbuf *mprev;
 182         struct esp *esp;
 183         struct esptail *esptail;
 184         struct secasvar *sav = isr->sav;
 185         const struct esp_algorithm *algo;
 186         u_int32_t spi;
 187         u_int8_t nxt = 0;
 188         size_t plen;    /* payload length to be encrypted */
 189         size_t espoff;
 190         int ivlen;
 191         int afnumber;
 192         size_t extendsiz;
 193         int error = 0;
 194         struct ipsecstat *stat;
 195
 196         switch (af) {
 197 #ifdef INET
 198         case AF_INET:
 199                 afnumber = 4;
 200                 stat = &ipsecstat;
 201                 break;
 202 #endif
 203 #ifdef INET6
 204         case AF_INET6:
 205                 afnumber = 6;
 206                 stat = &ipsec6stat;
 207                 break;
 208 #endif
 209         default:
 210                 ipseclog((LOG_ERR, "esp_output: unsupported af %d\n", af));
 211                 return 0;       /* no change at all */
 212         }
 213
 214         /* some sanity check */
 215         if ((sav->flags & SADB_X_EXT_OLD) == 0 && !sav->replay) {
 216                 switch (af) {
 217 #ifdef INET
 218                 case AF_INET:
 219                     {
 220                         struct ip *ip;
 221
 222                         ip = mtod(m, struct ip *);
 223                         ipseclog((LOG_DEBUG, "esp4_output: internal error: "
 224                                 "sav->replay is null: %x->%x, SPI=%u\n",
 225                                 (u_int32_t)ntohl(ip->ip_src.s_addr),
 226                                 (u_int32_t)ntohl(ip->ip_dst.s_addr),
 227                                 (u_int32_t)ntohl(sav->spi)));
 228                         ipsecstat.out_inval++;
 229                         break;
 230                     }
 231 #endif /* INET */
 232 #ifdef INET6
 233                 case AF_INET6:
 234                         ipseclog((LOG_DEBUG, "esp6_output: internal error: "
 235                                 "sav->replay is null: SPI=%u\n",
 236                                 (u_int32_t)ntohl(sav->spi)));
 237                         ipsec6stat.out_inval++;
 238                         break;
 239 #endif /* INET6 */
 240                 default:
 241                         panic("esp_output: should not reach here");
 242                 }
 243                 m_freem(m);
 244                 return EINVAL;
 245         }
 246
 247         algo = esp_algorithm_lookup(sav->alg_enc);
 248         if (!algo) {
 249                 ipseclog((LOG_ERR, "esp_output: unsupported algorithm: "
 250                     "SPI=%u\n", (u_int32_t)ntohl(sav->spi)));
 251                 m_freem(m);
 252                 return EINVAL;
 253         }
 254         spi = sav->spi;
 255         ivlen = sav->ivlen;
 256         /* should be okey */
 257         if (ivlen < 0) {
 258                 panic("invalid ivlen");
 259         }
 260
 261     {
 262         /*
 263          * insert ESP header.
 264          * XXX inserts ESP header right after IPv4 header.  should
 265          * chase the header chain.
 266          * XXX sequential number
 267          */
 268 #ifdef INET
 269         struct ip *ip = NULL;
 270 #endif
 271 #ifdef INET6
 272         struct ip6_hdr *ip6 = NULL;
 273 #endif
 274         size_t esplen;  /* sizeof(struct esp/newesp) */
 275         size_t esphlen; /* sizeof(struct esp/newesp) + ivlen */
 276         size_t hlen = 0;        /* ip header len */
 277
 278         if (sav->flags & SADB_X_EXT_OLD) {
 279                 /* RFC 1827 */
 280                 esplen = sizeof(struct esp);
 281         } else {
 282                 /* RFC 2406 */
 283                 if (sav->flags & SADB_X_EXT_DERIV)
 284                         esplen = sizeof(struct esp);
 285                 else
 286                         esplen = sizeof(struct newesp);
 287         }
 288         esphlen = esplen + ivlen;
 289
 290         for (mprev = m; mprev && mprev->m_next != md; mprev = mprev->m_next)
 291                 ;
 292         if (mprev == NULL || mprev->m_next != md) {
 293                 ipseclog((LOG_DEBUG, "esp%d_output: md is not in chain\n",
 294                     afnumber));
 295                 m_freem(m);
 296                 return EINVAL;
 297         }
 298
 299         plen = 0;
 300         for (n = md; n; n = n->m_next)
 301                 plen += n->m_len;
 302
 303         switch (af) {
 304 #ifdef INET
 305         case AF_INET:
 306                 ip = mtod(m, struct ip *);
 307 #ifdef _IP_VHL
 308                 hlen = IP_VHL_HL(ip->ip_vhl) << 2;
 309 #else
 310                 hlen = ip->ip_hl << 2;
 311 #endif
 312                 break;
 313 #endif
 314 #ifdef INET6
 315         case AF_INET6:
 316                 ip6 = mtod(m, struct ip6_hdr *);
 317                 hlen = sizeof(*ip6);
 318                 break;
 319 #endif
 320         }
 321
 322         /* make the packet over-writable */
 323         mprev->m_next = NULL;
 324         if ((md = ipsec_copypkt(md)) == NULL) {
 325                 m_freem(m);
 326                 error = ENOBUFS;
 327                 goto fail;
 328         }
 329         mprev->m_next = md;
 330
 331         espoff = m->m_pkthdr.len - plen;
 332
 333         /*
 334          * grow the mbuf to accomodate ESP header.
 335          * before: IP ... payload
 336          * after:  IP ... ESP IV payload
 337          */
 338         if (M_LEADINGSPACE(md) < esphlen || (md->m_flags & M_EXT)) {
 339                 MGET(n, MB_DONTWAIT, MT_DATA);
 340                 if (!n) {
 341                         m_freem(m);
 342                         error = ENOBUFS;
 343                         goto fail;
 344                 }
 345                 n->m_len = esphlen;
 346                 mprev->m_next = n;
 347                 n->m_next = md;
 348                 m->m_pkthdr.len += esphlen;
 349                 esp = mtod(n, struct esp *);
 350         } else {
 351                 md->m_len += esphlen;
 352                 md->m_data -= esphlen;
 353                 m->m_pkthdr.len += esphlen;
 354                 esp = mtod(md, struct esp *);
 355         }
 356
 357         nxt = *nexthdrp;
 358         *nexthdrp = IPPROTO_ESP;
 359         switch (af) {
 360 #ifdef INET
 361         case AF_INET:
 362                 if (esphlen < (IP_MAXPACKET - ntohs(ip->ip_len)))
 363                         ip->ip_len = htons(ntohs(ip->ip_len) + esphlen);
 364                 else {
 365                         ipseclog((LOG_ERR,
 366                             "IPv4 ESP output: size exceeds limit\n"));
 367                         ipsecstat.out_inval++;
 368                         m_freem(m);
 369                         error = EMSGSIZE;
 370                         goto fail;
 371                 }
 372                 break;
 373 #endif
 374 #ifdef INET6
 375         case AF_INET6:
 376                 /* total packet length will be computed in ip6_output() */
 377                 break;
 378 #endif
 379         }
 380     }
 381
 382         /* initialize esp header. */
 383         esp->esp_spi = spi;
 384         if ((sav->flags & SADB_X_EXT_OLD) == 0) {
 385                 struct newesp *nesp;
 386                 nesp = (struct newesp *)esp;
 387                 if (sav->replay->count == ~0) {
 388                         if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) {
 389                                 /* XXX Is it noisy ? */
 390                                 ipseclog((LOG_WARNING,
 391                                     "replay counter overflowed. %s\n",
 392                                     ipsec_logsastr(sav)));
 393                                 stat->out_inval++;
 394                                 m_freem(m);
 395                                 return EINVAL;
 396                         }
 397                 }
 398                 sav->replay->count++;
 399                 /*
 400                  * XXX sequence number must not be cycled, if the SA is
 401                  * installed by IKE daemon.
 402                  */
 403                 nesp->esp_seq = htonl(sav->replay->count & 0xffffffff);
 404         }
 405
 406     {
 407         /*
 408          * find the last mbuf. make some room for ESP trailer.
 409          */
 410 #ifdef INET
 411         struct ip *ip = NULL;
 412 #endif
 413         size_t padbound;
 414         u_char *extend;
 415         int i;
 416         int randpadmax;
 417
 418         if (algo->padbound)
 419                 padbound = algo->padbound;
 420         else
 421                 padbound = 4;
 422         /* ESP packet, including nxthdr field, must be length of 4n */
 423         if (padbound < 4)
 424                 padbound = 4;
 425
 426         extendsiz = padbound - (plen % padbound);
 427         if (extendsiz == 1)
 428                 extendsiz = padbound + 1;
 429
 430         /* random padding */
 431         switch (af) {
 432 #ifdef INET
 433         case AF_INET:
 434                 randpadmax = ip4_esp_randpad;
 435                 break;
 436 #endif
 437 #ifdef INET6
 438         case AF_INET6:
 439                 randpadmax = ip6_esp_randpad;
 440                 break;
 441 #endif
 442         default:
 443                 randpadmax = -1;
 444                 break;
 445         }
 446         if (randpadmax < 0 || plen + extendsiz >= randpadmax)
 447                 ;
 448         else {
 449                 int n;
 450
 451                 /* round */
 452                 randpadmax = (randpadmax / padbound) * padbound;
 453                 n = (randpadmax - plen + extendsiz) / padbound;
 454
 455                 if (n > 0)
 456                         n = (krandom() % n) * padbound;
 457                 else
 458                         n = 0;
 459
 460                 /*
 461                  * make sure we do not pad too much.
 462                  * MLEN limitation comes from the trailer attachment
 463                  * code below.
 464                  * 256 limitation comes from sequential padding.
 465                  * also, the 1-octet length field in ESP trailer imposes
 466                  * limitation (but is less strict than sequential padding
 467                  * as length field do not count the last 2 octets).
 468                  */
 469                 if (extendsiz + n <= MLEN && extendsiz + n < 256)
 470                         extendsiz += n;
 471         }
 472
 473 #ifdef DIAGNOSTIC
 474         if (extendsiz > MLEN || extendsiz >= 256)
 475                 panic("extendsiz too big in esp_output");
 476 #endif
 477
 478         n = m;
 479         while (n->m_next)
 480                 n = n->m_next;
 481
 482         /*
 483          * if M_EXT, the external mbuf data may be shared among
 484          * two consequtive TCP packets, and it may be unsafe to use the
 485          * trailing space.
 486          */
 487         if (!(n->m_flags & M_EXT) && extendsiz < M_TRAILINGSPACE(n)) {
 488                 extend = mtod(n, u_char *) + n->m_len;
 489                 n->m_len += extendsiz;
 490                 m->m_pkthdr.len += extendsiz;
 491         } else {
 492                 struct mbuf *nn;
 493
 494                 MGET(nn, MB_DONTWAIT, MT_DATA);
 495                 if (!nn) {
 496                         ipseclog((LOG_DEBUG, "esp%d_output: can't alloc mbuf",
 497                             afnumber));
 498                         m_freem(m);
 499                         error = ENOBUFS;
 500                         goto fail;
 501                 }
 502                 extend = mtod(nn, u_char *);
 503                 nn->m_len = extendsiz;
 504                 nn->m_next = NULL;
 505                 n->m_next = nn;
 506                 n = nn;
 507                 m->m_pkthdr.len += extendsiz;
 508         }
 509         switch (sav->flags & SADB_X_EXT_PMASK) {
 510         case SADB_X_EXT_PRAND:
 511                 key_randomfill(extend, extendsiz);
 512                 break;
 513         case SADB_X_EXT_PZERO:
 514                 bzero(extend, extendsiz);
 515                 break;
 516         case SADB_X_EXT_PSEQ:
 517                 for (i = 0; i < extendsiz; i++)
 518                         extend[i] = (i + 1) & 0xff;
 519                 break;
 520         }
 521
 522         /* initialize esp trailer. */
 523         esptail = (struct esptail *)
 524                 (mtod(n, u_int8_t *) + n->m_len - sizeof(struct esptail));
 525         esptail->esp_nxt = nxt;
 526         esptail->esp_padlen = extendsiz - 2;
 527
 528         /* modify IP header (for ESP header part only) */
 529         switch (af) {
 530 #ifdef INET
 531         case AF_INET:
 532                 ip = mtod(m, struct ip *);
 533                 if (extendsiz < (IP_MAXPACKET - ntohs(ip->ip_len)))
 534                         ip->ip_len = htons(ntohs(ip->ip_len) + extendsiz);
 535                 else {
 536                         ipseclog((LOG_ERR,
 537                             "IPv4 ESP output: size exceeds limit\n"));
 538                         ipsecstat.out_inval++;
 539                         m_freem(m);
 540                         error = EMSGSIZE;
 541                         goto fail;
 542                 }
 543                 break;
 544 #endif
 545 #ifdef INET6
 546         case AF_INET6:
 547                 /* total packet length will be computed in ip6_output() */
 548                 break;
 549 #endif
 550         }
 551     }
 552
 553         /*
 554          * pre-compute and cache intermediate key
 555          */
 556         error = esp_schedule(algo, sav);
 557         if (error) {
 558                 m_freem(m);
 559                 stat->out_inval++;
 560                 goto fail;
 561         }
 562
 563         /*
 564          * encrypt the packet, based on security association
 565          * and the algorithm specified.
 566          */
 567         if (!algo->encrypt)
 568                 panic("internal error: no encrypt function");
 569         if ((*algo->encrypt)(m, espoff, plen + extendsiz, sav, algo, ivlen)) {
 570                 /* m is already freed */
 571                 ipseclog((LOG_ERR, "packet encryption failure\n"));
 572                 stat->out_inval++;
 573                 error = EINVAL;
 574                 goto fail;
 575         }
 576
 577         /*
 578          * calculate ICV if required.
 579          */
 580         if (!sav->replay)
 581                 goto noantireplay;
 582         if (!sav->key_auth)
 583                 goto noantireplay;
 584         if (sav->alg_auth == SADB_AALG_NONE)
 585                 goto noantireplay;
 586
 587     {
 588         const struct ah_algorithm *aalgo;
 589         u_char authbuf[AH_MAXSUMSIZE];
 590         struct mbuf *n;
 591         u_char *p;
 592         size_t siz;
 593 #ifdef INET
 594         struct ip *ip;
 595 #endif
 596
 597         aalgo = ah_algorithm_lookup(sav->alg_auth);
 598         if (!aalgo)
 599                 goto noantireplay;
 600         siz = ((aalgo->sumsiz)(sav) + 3) & ~(4 - 1);
 601         if (AH_MAXSUMSIZE < siz)
 602                 panic("assertion failed for AH_MAXSUMSIZE");
 603
 604         if (esp_auth(m, espoff, m->m_pkthdr.len - espoff, sav, authbuf)) {
 605                 ipseclog((LOG_ERR, "ESP checksum generation failure\n"));
 606                 m_freem(m);
 607                 error = EINVAL;
 608                 stat->out_inval++;
 609                 goto fail;
 610         }
 611
 612         n = m;
 613         while (n->m_next)
 614                 n = n->m_next;
 615
 616         if (!(n->m_flags & M_EXT) && siz < M_TRAILINGSPACE(n)) { /* XXX */
 617                 n->m_len += siz;
 618                 m->m_pkthdr.len += siz;
 619                 p = mtod(n, u_char *) + n->m_len - siz;
 620         } else {
 621                 struct mbuf *nn;
 622
 623                 MGET(nn, MB_DONTWAIT, MT_DATA);
 624                 if (!nn) {
 625                         ipseclog((LOG_DEBUG, "can't alloc mbuf in esp%d_output",
 626                             afnumber));
 627                         m_freem(m);
 628                         error = ENOBUFS;
 629                         goto fail;
 630                 }
 631                 nn->m_len = siz;
 632                 nn->m_next = NULL;
 633                 n->m_next = nn;
 634                 n = nn;
 635                 m->m_pkthdr.len += siz;
 636                 p = mtod(nn, u_char *);
 637         }
 638         bcopy(authbuf, p, siz);
 639
 640         /* modify IP header (for ESP header part only) */
 641         switch (af) {
 642 #ifdef INET
 643         case AF_INET:
 644                 ip = mtod(m, struct ip *);
 645                 if (siz < (IP_MAXPACKET - ntohs(ip->ip_len)))
 646                         ip->ip_len = htons(ntohs(ip->ip_len) + siz);
 647                 else {
 648                         ipseclog((LOG_ERR,
 649                             "IPv4 ESP output: size exceeds limit\n"));
 650                         ipsecstat.out_inval++;
 651                         m_freem(m);
 652                         error = EMSGSIZE;
 653                         goto fail;
 654                 }
 655                 break;
 656 #endif
 657 #ifdef INET6
 658         case AF_INET6:
 659                 /* total packet length will be computed in ip6_output() */
 660                 break;
 661 #endif
 662         }
 663     }
 664
 665 noantireplay:
 666         if (!m) {
 667                 ipseclog((LOG_ERR,
 668                     "NULL mbuf after encryption in esp%d_output", afnumber));
 669         } else
 670                 stat->out_success++;
 671         stat->out_esphist[sav->alg_enc]++;
 672         key_sa_recordxfer(sav, m);
 673         return 0;
 674
 675 fail:
 676 #if 1
 677         return error;
 678 #else
 679         panic("something bad in esp_output");
 680 #endif
 681 }
 682
 683 #ifdef INET
 684 int
 685 esp4_output(struct mbuf *m, struct ipsecrequest *isr)
 686 {
 687         struct ip *ip;
 688         if (m->m_len < sizeof(struct ip)) {
 689                 ipseclog((LOG_DEBUG, "esp4_output: first mbuf too short\n"));
 690                 m_freem(m);
 691                 return 0;
 692         }
 693         ip = mtod(m, struct ip *);
 694         /* XXX assumes that m->m_next points to payload */
 695         return esp_output(m, &ip->ip_p, m->m_next, isr, AF_INET);
 696 }
 697 #endif /* INET */
 698
 699 #ifdef INET6
 700 int
 701 esp6_output(struct mbuf *m, u_char *nexthdrp, struct mbuf *md,
 702             struct ipsecrequest *isr)
 703 {
 704         if (m->m_len < sizeof(struct ip6_hdr)) {
 705                 ipseclog((LOG_DEBUG, "esp6_output: first mbuf too short\n"));
 706                 m_freem(m);
 707                 return 0;
 708         }
 709         return esp_output(m, nexthdrp, md, isr, AF_INET6);
 710 }
 711 #endif /* INET6 */