1 /* 2 * Copyright (C)2002 USAGI/WIDE Project 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 17 * 18 * Authors 19 * 20 * Mitsuru KANDA @USAGI : IPv6 Support 21 * Kazunori MIYAZAWA @USAGI : 22 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 23 * 24 * This file is derived from net/ipv4/ah.c. 25 */ 26 27 #include <crypto/hash.h> 28 #include <linux/module.h> 29 #include <net/ip.h> 30 #include <net/ah.h> 31 #include <linux/crypto.h> 32 #include <linux/pfkeyv2.h> 33 #include <linux/string.h> 34 #include <linux/scatterlist.h> 35 #include <net/icmp.h> 36 #include <net/ipv6.h> 37 #include <net/protocol.h> 38 #include <net/xfrm.h> 39 40 #define IPV6HDR_BASELEN 8 41 42 struct tmp_ext { 43 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 44 struct in6_addr saddr; 45 #endif 46 struct in6_addr daddr; 47 char hdrs[0]; 48 }; 49 50 struct ah_skb_cb { 51 struct xfrm_skb_cb xfrm; 52 void *tmp; 53 }; 54 55 #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) 56 57 static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, 58 unsigned int size) 59 { 60 unsigned int len; 61 62 len = size + crypto_ahash_digestsize(ahash) + 63 (crypto_ahash_alignmask(ahash) & 64 ~(crypto_tfm_ctx_alignment() - 1)); 65 66 len = ALIGN(len, crypto_tfm_ctx_alignment()); 67 68 len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); 69 len = ALIGN(len, __alignof__(struct scatterlist)); 70 71 len += sizeof(struct scatterlist) * nfrags; 72 73 return kmalloc(len, GFP_ATOMIC); 74 } 75 76 static inline struct tmp_ext *ah_tmp_ext(void *base) 77 { 78 return base + IPV6HDR_BASELEN; 79 } 80 81 static inline u8 *ah_tmp_auth(u8 *tmp, unsigned int offset) 82 { 83 return tmp + offset; 84 } 85 86 static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, 87 unsigned int offset) 88 { 89 return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); 90 } 91 92 static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, 93 u8 *icv) 94 { 95 struct ahash_request *req; 96 97 req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), 98 crypto_tfm_ctx_alignment()); 99 100 ahash_request_set_tfm(req, ahash); 101 102 return req; 103 } 104 105 static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, 106 struct ahash_request *req) 107 { 108 return (void *)ALIGN((unsigned long)(req + 1) + 109 crypto_ahash_reqsize(ahash), 110 __alignof__(struct scatterlist)); 111 } 112 113 static int zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr) 114 { 115 u8 *opt = (u8 *)opthdr; 116 int len = ipv6_optlen(opthdr); 117 int off = 0; 118 int optlen = 0; 119 120 off += 2; 121 len -= 2; 122 123 while (len > 0) { 124 125 switch (opt[off]) { 126 127 case IPV6_TLV_PAD0: 128 optlen = 1; 129 break; 130 default: 131 if (len < 2) 132 goto bad; 133 optlen = opt[off+1]+2; 134 if (len < optlen) 135 goto bad; 136 if (opt[off] & 0x20) 137 memset(&opt[off+2], 0, opt[off+1]); 138 break; 139 } 140 141 off += optlen; 142 len -= optlen; 143 } 144 if (len == 0) 145 return 1; 146 147 bad: 148 return 0; 149 } 150 151 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 152 /** 153 * ipv6_rearrange_destopt - rearrange IPv6 destination options header 154 * @iph: IPv6 header 155 * @destopt: destionation options header 156 */ 157 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) 158 { 159 u8 *opt = (u8 *)destopt; 160 int len = ipv6_optlen(destopt); 161 int off = 0; 162 int optlen = 0; 163 164 off += 2; 165 len -= 2; 166 167 while (len > 0) { 168 169 switch (opt[off]) { 170 171 case IPV6_TLV_PAD0: 172 optlen = 1; 173 break; 174 default: 175 if (len < 2) 176 goto bad; 177 optlen = opt[off+1]+2; 178 if (len < optlen) 179 goto bad; 180 181 /* Rearrange the source address in @iph and the 182 * addresses in home address option for final source. 183 * See 11.3.2 of RFC 3775 for details. 184 */ 185 if (opt[off] == IPV6_TLV_HAO) { 186 struct in6_addr final_addr; 187 struct ipv6_destopt_hao *hao; 188 189 hao = (struct ipv6_destopt_hao *)&opt[off]; 190 if (hao->length != sizeof(hao->addr)) { 191 if (net_ratelimit()) 192 printk(KERN_WARNING "destopt hao: invalid header length: %u\n", hao->length); 193 goto bad; 194 } 195 ipv6_addr_copy(&final_addr, &hao->addr); 196 ipv6_addr_copy(&hao->addr, &iph->saddr); 197 ipv6_addr_copy(&iph->saddr, &final_addr); 198 } 199 break; 200 } 201 202 off += optlen; 203 len -= optlen; 204 } 205 /* Note: ok if len == 0 */ 206 bad: 207 return; 208 } 209 #else 210 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {} 211 #endif 212 213 /** 214 * ipv6_rearrange_rthdr - rearrange IPv6 routing header 215 * @iph: IPv6 header 216 * @rthdr: routing header 217 * 218 * Rearrange the destination address in @iph and the addresses in @rthdr 219 * so that they appear in the order they will at the final destination. 220 * See Appendix A2 of RFC 2402 for details. 221 */ 222 static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr) 223 { 224 int segments, segments_left; 225 struct in6_addr *addrs; 226 struct in6_addr final_addr; 227 228 segments_left = rthdr->segments_left; 229 if (segments_left == 0) 230 return; 231 rthdr->segments_left = 0; 232 233 /* The value of rthdr->hdrlen has been verified either by the system 234 * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming 235 * packets. So we can assume that it is even and that segments is 236 * greater than or equal to segments_left. 237 * 238 * For the same reason we can assume that this option is of type 0. 239 */ 240 segments = rthdr->hdrlen >> 1; 241 242 addrs = ((struct rt0_hdr *)rthdr)->addr; 243 ipv6_addr_copy(&final_addr, addrs + segments - 1); 244 245 addrs += segments - segments_left; 246 memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs)); 247 248 ipv6_addr_copy(addrs, &iph->daddr); 249 ipv6_addr_copy(&iph->daddr, &final_addr); 250 } 251 252 static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir) 253 { 254 union { 255 struct ipv6hdr *iph; 256 struct ipv6_opt_hdr *opth; 257 struct ipv6_rt_hdr *rth; 258 char *raw; 259 } exthdr = { .iph = iph }; 260 char *end = exthdr.raw + len; 261 int nexthdr = iph->nexthdr; 262 263 exthdr.iph++; 264 265 while (exthdr.raw < end) { 266 switch (nexthdr) { 267 case NEXTHDR_DEST: 268 if (dir == XFRM_POLICY_OUT) 269 ipv6_rearrange_destopt(iph, exthdr.opth); 270 case NEXTHDR_HOP: 271 if (!zero_out_mutable_opts(exthdr.opth)) { 272 LIMIT_NETDEBUG( 273 KERN_WARNING "overrun %sopts\n", 274 nexthdr == NEXTHDR_HOP ? 275 "hop" : "dest"); 276 return -EINVAL; 277 } 278 break; 279 280 case NEXTHDR_ROUTING: 281 ipv6_rearrange_rthdr(iph, exthdr.rth); 282 break; 283 284 default : 285 return 0; 286 } 287 288 nexthdr = exthdr.opth->nexthdr; 289 exthdr.raw += ipv6_optlen(exthdr.opth); 290 } 291 292 return 0; 293 } 294 295 static void ah6_output_done(struct crypto_async_request *base, int err) 296 { 297 int extlen; 298 u8 *iph_base; 299 u8 *icv; 300 struct sk_buff *skb = base->data; 301 struct xfrm_state *x = skb_dst(skb)->xfrm; 302 struct ah_data *ahp = x->data; 303 struct ipv6hdr *top_iph = ipv6_hdr(skb); 304 struct ip_auth_hdr *ah = ip_auth_hdr(skb); 305 struct tmp_ext *iph_ext; 306 307 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr); 308 if (extlen) 309 extlen += sizeof(*iph_ext); 310 311 iph_base = AH_SKB_CB(skb)->tmp; 312 iph_ext = ah_tmp_ext(iph_base); 313 icv = ah_tmp_icv(ahp->ahash, iph_ext, extlen); 314 315 memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 316 memcpy(top_iph, iph_base, IPV6HDR_BASELEN); 317 318 if (extlen) { 319 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 320 memcpy(&top_iph->saddr, iph_ext, extlen); 321 #else 322 memcpy(&top_iph->daddr, iph_ext, extlen); 323 #endif 324 } 325 326 err = ah->nexthdr; 327 328 kfree(AH_SKB_CB(skb)->tmp); 329 xfrm_output_resume(skb, err); 330 } 331 332 static int ah6_output(struct xfrm_state *x, struct sk_buff *skb) 333 { 334 int err; 335 int nfrags; 336 int extlen; 337 u8 *iph_base; 338 u8 *icv; 339 u8 nexthdr; 340 struct sk_buff *trailer; 341 struct crypto_ahash *ahash; 342 struct ahash_request *req; 343 struct scatterlist *sg; 344 struct ipv6hdr *top_iph; 345 struct ip_auth_hdr *ah; 346 struct ah_data *ahp; 347 struct tmp_ext *iph_ext; 348 349 ahp = x->data; 350 ahash = ahp->ahash; 351 352 if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 353 goto out; 354 nfrags = err; 355 356 skb_push(skb, -skb_network_offset(skb)); 357 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr); 358 if (extlen) 359 extlen += sizeof(*iph_ext); 360 361 err = -ENOMEM; 362 iph_base = ah_alloc_tmp(ahash, nfrags, IPV6HDR_BASELEN + extlen); 363 if (!iph_base) 364 goto out; 365 366 iph_ext = ah_tmp_ext(iph_base); 367 icv = ah_tmp_icv(ahash, iph_ext, extlen); 368 req = ah_tmp_req(ahash, icv); 369 sg = ah_req_sg(ahash, req); 370 371 ah = ip_auth_hdr(skb); 372 memset(ah->auth_data, 0, ahp->icv_trunc_len); 373 374 top_iph = ipv6_hdr(skb); 375 top_iph->payload_len = htons(skb->len - sizeof(*top_iph)); 376 377 nexthdr = *skb_mac_header(skb); 378 *skb_mac_header(skb) = IPPROTO_AH; 379 380 /* When there are no extension headers, we only need to save the first 381 * 8 bytes of the base IP header. 382 */ 383 memcpy(iph_base, top_iph, IPV6HDR_BASELEN); 384 385 if (extlen) { 386 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 387 memcpy(iph_ext, &top_iph->saddr, extlen); 388 #else 389 memcpy(iph_ext, &top_iph->daddr, extlen); 390 #endif 391 err = ipv6_clear_mutable_options(top_iph, 392 extlen - sizeof(*iph_ext) + 393 sizeof(*top_iph), 394 XFRM_POLICY_OUT); 395 if (err) 396 goto out_free; 397 } 398 399 ah->nexthdr = nexthdr; 400 401 top_iph->priority = 0; 402 top_iph->flow_lbl[0] = 0; 403 top_iph->flow_lbl[1] = 0; 404 top_iph->flow_lbl[2] = 0; 405 top_iph->hop_limit = 0; 406 407 ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; 408 409 ah->reserved = 0; 410 ah->spi = x->id.spi; 411 ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output); 412 413 sg_init_table(sg, nfrags); 414 skb_to_sgvec(skb, sg, 0, skb->len); 415 416 ahash_request_set_crypt(req, sg, icv, skb->len); 417 ahash_request_set_callback(req, 0, ah6_output_done, skb); 418 419 AH_SKB_CB(skb)->tmp = iph_base; 420 421 err = crypto_ahash_digest(req); 422 if (err) { 423 if (err == -EINPROGRESS) 424 goto out; 425 426 if (err == -EBUSY) 427 err = NET_XMIT_DROP; 428 goto out_free; 429 } 430 431 memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 432 memcpy(top_iph, iph_base, IPV6HDR_BASELEN); 433 434 if (extlen) { 435 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 436 memcpy(&top_iph->saddr, iph_ext, extlen); 437 #else 438 memcpy(&top_iph->daddr, iph_ext, extlen); 439 #endif 440 } 441 442 out_free: 443 kfree(iph_base); 444 out: 445 return err; 446 } 447 448 static void ah6_input_done(struct crypto_async_request *base, int err) 449 { 450 u8 *auth_data; 451 u8 *icv; 452 u8 *work_iph; 453 struct sk_buff *skb = base->data; 454 struct xfrm_state *x = xfrm_input_state(skb); 455 struct ah_data *ahp = x->data; 456 struct ip_auth_hdr *ah = ip_auth_hdr(skb); 457 int hdr_len = skb_network_header_len(skb); 458 int ah_hlen = (ah->hdrlen + 2) << 2; 459 460 work_iph = AH_SKB_CB(skb)->tmp; 461 auth_data = ah_tmp_auth(work_iph, hdr_len); 462 icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len); 463 464 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 465 if (err) 466 goto out; 467 468 skb->network_header += ah_hlen; 469 memcpy(skb_network_header(skb), work_iph, hdr_len); 470 __skb_pull(skb, ah_hlen + hdr_len); 471 skb_set_transport_header(skb, -hdr_len); 472 473 err = ah->nexthdr; 474 out: 475 kfree(AH_SKB_CB(skb)->tmp); 476 xfrm_input_resume(skb, err); 477 } 478 479 480 481 static int ah6_input(struct xfrm_state *x, struct sk_buff *skb) 482 { 483 /* 484 * Before process AH 485 * [IPv6][Ext1][Ext2][AH][Dest][Payload] 486 * |<-------------->| hdr_len 487 * 488 * To erase AH: 489 * Keeping copy of cleared headers. After AH processing, 490 * Moving the pointer of skb->network_header by using skb_pull as long 491 * as AH header length. Then copy back the copy as long as hdr_len 492 * If destination header following AH exists, copy it into after [Ext2]. 493 * 494 * |<>|[IPv6][Ext1][Ext2][Dest][Payload] 495 * There is offset of AH before IPv6 header after the process. 496 */ 497 498 u8 *auth_data; 499 u8 *icv; 500 u8 *work_iph; 501 struct sk_buff *trailer; 502 struct crypto_ahash *ahash; 503 struct ahash_request *req; 504 struct scatterlist *sg; 505 struct ip_auth_hdr *ah; 506 struct ipv6hdr *ip6h; 507 struct ah_data *ahp; 508 u16 hdr_len; 509 u16 ah_hlen; 510 int nexthdr; 511 int nfrags; 512 int err = -ENOMEM; 513 514 if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr))) 515 goto out; 516 517 /* We are going to _remove_ AH header to keep sockets happy, 518 * so... Later this can change. */ 519 if (skb_cloned(skb) && 520 pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) 521 goto out; 522 523 skb->ip_summed = CHECKSUM_NONE; 524 525 hdr_len = skb_network_header_len(skb); 526 ah = (struct ip_auth_hdr *)skb->data; 527 ahp = x->data; 528 ahash = ahp->ahash; 529 530 nexthdr = ah->nexthdr; 531 ah_hlen = (ah->hdrlen + 2) << 2; 532 533 if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && 534 ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) 535 goto out; 536 537 if (!pskb_may_pull(skb, ah_hlen)) 538 goto out; 539 540 ip6h = ipv6_hdr(skb); 541 542 skb_push(skb, hdr_len); 543 544 if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 545 goto out; 546 nfrags = err; 547 548 work_iph = ah_alloc_tmp(ahash, nfrags, hdr_len + ahp->icv_trunc_len); 549 if (!work_iph) 550 goto out; 551 552 auth_data = ah_tmp_auth(work_iph, hdr_len); 553 icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len); 554 req = ah_tmp_req(ahash, icv); 555 sg = ah_req_sg(ahash, req); 556 557 memcpy(work_iph, ip6h, hdr_len); 558 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); 559 memset(ah->auth_data, 0, ahp->icv_trunc_len); 560 561 if (ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN)) 562 goto out_free; 563 564 ip6h->priority = 0; 565 ip6h->flow_lbl[0] = 0; 566 ip6h->flow_lbl[1] = 0; 567 ip6h->flow_lbl[2] = 0; 568 ip6h->hop_limit = 0; 569 570 sg_init_table(sg, nfrags); 571 skb_to_sgvec(skb, sg, 0, skb->len); 572 573 ahash_request_set_crypt(req, sg, icv, skb->len); 574 ahash_request_set_callback(req, 0, ah6_input_done, skb); 575 576 AH_SKB_CB(skb)->tmp = work_iph; 577 578 err = crypto_ahash_digest(req); 579 if (err) { 580 if (err == -EINPROGRESS) 581 goto out; 582 583 if (err == -EBUSY) 584 err = NET_XMIT_DROP; 585 goto out_free; 586 } 587 588 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 589 if (err) 590 goto out_free; 591 592 skb->network_header += ah_hlen; 593 memcpy(skb_network_header(skb), work_iph, hdr_len); 594 skb->transport_header = skb->network_header; 595 __skb_pull(skb, ah_hlen + hdr_len); 596 597 err = nexthdr; 598 599 out_free: 600 kfree(work_iph); 601 out: 602 return err; 603 } 604 605 static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 606 u8 type, u8 code, int offset, __be32 info) 607 { 608 struct net *net = dev_net(skb->dev); 609 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data; 610 struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset); 611 struct xfrm_state *x; 612 613 if (type != ICMPV6_DEST_UNREACH && 614 type != ICMPV6_PKT_TOOBIG) 615 return; 616 617 x = xfrm_state_lookup(net, (xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6); 618 if (!x) 619 return; 620 621 NETDEBUG(KERN_DEBUG "pmtu discovery on SA AH/%08x/%pI6\n", 622 ntohl(ah->spi), &iph->daddr); 623 624 xfrm_state_put(x); 625 } 626 627 static int ah6_init_state(struct xfrm_state *x) 628 { 629 struct ah_data *ahp = NULL; 630 struct xfrm_algo_desc *aalg_desc; 631 struct crypto_ahash *ahash; 632 633 if (!x->aalg) 634 goto error; 635 636 if (x->encap) 637 goto error; 638 639 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); 640 if (ahp == NULL) 641 return -ENOMEM; 642 643 ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); 644 if (IS_ERR(ahash)) 645 goto error; 646 647 ahp->ahash = ahash; 648 if (crypto_ahash_setkey(ahash, x->aalg->alg_key, 649 (x->aalg->alg_key_len + 7) / 8)) 650 goto error; 651 652 /* 653 * Lookup the algorithm description maintained by xfrm_algo, 654 * verify crypto transform properties, and store information 655 * we need for AH processing. This lookup cannot fail here 656 * after a successful crypto_alloc_hash(). 657 */ 658 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 659 BUG_ON(!aalg_desc); 660 661 if (aalg_desc->uinfo.auth.icv_fullbits/8 != 662 crypto_ahash_digestsize(ahash)) { 663 printk(KERN_INFO "AH: %s digestsize %u != %hu\n", 664 x->aalg->alg_name, crypto_ahash_digestsize(ahash), 665 aalg_desc->uinfo.auth.icv_fullbits/8); 666 goto error; 667 } 668 669 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; 670 ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; 671 672 BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN); 673 674 x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + 675 ahp->icv_trunc_len); 676 switch (x->props.mode) { 677 case XFRM_MODE_BEET: 678 case XFRM_MODE_TRANSPORT: 679 break; 680 case XFRM_MODE_TUNNEL: 681 x->props.header_len += sizeof(struct ipv6hdr); 682 break; 683 default: 684 goto error; 685 } 686 x->data = ahp; 687 688 return 0; 689 690 error: 691 if (ahp) { 692 crypto_free_ahash(ahp->ahash); 693 kfree(ahp); 694 } 695 return -EINVAL; 696 } 697 698 static void ah6_destroy(struct xfrm_state *x) 699 { 700 struct ah_data *ahp = x->data; 701 702 if (!ahp) 703 return; 704 705 crypto_free_ahash(ahp->ahash); 706 kfree(ahp); 707 } 708 709 static const struct xfrm_type ah6_type = 710 { 711 .description = "AH6", 712 .owner = THIS_MODULE, 713 .proto = IPPROTO_AH, 714 .flags = XFRM_TYPE_REPLAY_PROT, 715 .init_state = ah6_init_state, 716 .destructor = ah6_destroy, 717 .input = ah6_input, 718 .output = ah6_output, 719 .hdr_offset = xfrm6_find_1stfragopt, 720 }; 721 722 static const struct inet6_protocol ah6_protocol = { 723 .handler = xfrm6_rcv, 724 .err_handler = ah6_err, 725 .flags = INET6_PROTO_NOPOLICY, 726 }; 727 728 static int __init ah6_init(void) 729 { 730 if (xfrm_register_type(&ah6_type, AF_INET6) < 0) { 731 printk(KERN_INFO "ipv6 ah init: can't add xfrm type\n"); 732 return -EAGAIN; 733 } 734 735 if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) { 736 printk(KERN_INFO "ipv6 ah init: can't add protocol\n"); 737 xfrm_unregister_type(&ah6_type, AF_INET6); 738 return -EAGAIN; 739 } 740 741 return 0; 742 } 743 744 static void __exit ah6_fini(void) 745 { 746 if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0) 747 printk(KERN_INFO "ipv6 ah close: can't remove protocol\n"); 748 749 if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0) 750 printk(KERN_INFO "ipv6 ah close: can't remove xfrm type\n"); 751 752 } 753 754 module_init(ah6_init); 755 module_exit(ah6_fini); 756 757 MODULE_LICENSE("GPL"); 758 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH); 759