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 <linux/slab.h> 30 #include <net/ip.h> 31 #include <net/ah.h> 32 #include <linux/crypto.h> 33 #include <linux/pfkeyv2.h> 34 #include <linux/string.h> 35 #include <linux/scatterlist.h> 36 #include <net/icmp.h> 37 #include <net/ipv6.h> 38 #include <net/protocol.h> 39 #include <net/xfrm.h> 40 41 #define IPV6HDR_BASELEN 8 42 43 struct tmp_ext { 44 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 45 struct in6_addr saddr; 46 #endif 47 struct in6_addr daddr; 48 char hdrs[0]; 49 }; 50 51 struct ah_skb_cb { 52 struct xfrm_skb_cb xfrm; 53 void *tmp; 54 }; 55 56 #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) 57 58 static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, 59 unsigned int size) 60 { 61 unsigned int len; 62 63 len = size + crypto_ahash_digestsize(ahash) + 64 (crypto_ahash_alignmask(ahash) & 65 ~(crypto_tfm_ctx_alignment() - 1)); 66 67 len = ALIGN(len, crypto_tfm_ctx_alignment()); 68 69 len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); 70 len = ALIGN(len, __alignof__(struct scatterlist)); 71 72 len += sizeof(struct scatterlist) * nfrags; 73 74 return kmalloc(len, GFP_ATOMIC); 75 } 76 77 static inline struct tmp_ext *ah_tmp_ext(void *base) 78 { 79 return base + IPV6HDR_BASELEN; 80 } 81 82 static inline u8 *ah_tmp_auth(u8 *tmp, unsigned int offset) 83 { 84 return tmp + offset; 85 } 86 87 static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, 88 unsigned int offset) 89 { 90 return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); 91 } 92 93 static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, 94 u8 *icv) 95 { 96 struct ahash_request *req; 97 98 req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), 99 crypto_tfm_ctx_alignment()); 100 101 ahash_request_set_tfm(req, ahash); 102 103 return req; 104 } 105 106 static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, 107 struct ahash_request *req) 108 { 109 return (void *)ALIGN((unsigned long)(req + 1) + 110 crypto_ahash_reqsize(ahash), 111 __alignof__(struct scatterlist)); 112 } 113 114 static int zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr) 115 { 116 u8 *opt = (u8 *)opthdr; 117 int len = ipv6_optlen(opthdr); 118 int off = 0; 119 int optlen = 0; 120 121 off += 2; 122 len -= 2; 123 124 while (len > 0) { 125 126 switch (opt[off]) { 127 128 case IPV6_TLV_PAD0: 129 optlen = 1; 130 break; 131 default: 132 if (len < 2) 133 goto bad; 134 optlen = opt[off+1]+2; 135 if (len < optlen) 136 goto bad; 137 if (opt[off] & 0x20) 138 memset(&opt[off+2], 0, opt[off+1]); 139 break; 140 } 141 142 off += optlen; 143 len -= optlen; 144 } 145 if (len == 0) 146 return 1; 147 148 bad: 149 return 0; 150 } 151 152 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 153 /** 154 * ipv6_rearrange_destopt - rearrange IPv6 destination options header 155 * @iph: IPv6 header 156 * @destopt: destionation options header 157 */ 158 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) 159 { 160 u8 *opt = (u8 *)destopt; 161 int len = ipv6_optlen(destopt); 162 int off = 0; 163 int optlen = 0; 164 165 off += 2; 166 len -= 2; 167 168 while (len > 0) { 169 170 switch (opt[off]) { 171 172 case IPV6_TLV_PAD0: 173 optlen = 1; 174 break; 175 default: 176 if (len < 2) 177 goto bad; 178 optlen = opt[off+1]+2; 179 if (len < optlen) 180 goto bad; 181 182 /* Rearrange the source address in @iph and the 183 * addresses in home address option for final source. 184 * See 11.3.2 of RFC 3775 for details. 185 */ 186 if (opt[off] == IPV6_TLV_HAO) { 187 struct in6_addr final_addr; 188 struct ipv6_destopt_hao *hao; 189 190 hao = (struct ipv6_destopt_hao *)&opt[off]; 191 if (hao->length != sizeof(hao->addr)) { 192 if (net_ratelimit()) 193 printk(KERN_WARNING "destopt hao: invalid header length: %u\n", hao->length); 194 goto bad; 195 } 196 ipv6_addr_copy(&final_addr, &hao->addr); 197 ipv6_addr_copy(&hao->addr, &iph->saddr); 198 ipv6_addr_copy(&iph->saddr, &final_addr); 199 } 200 break; 201 } 202 203 off += optlen; 204 len -= optlen; 205 } 206 /* Note: ok if len == 0 */ 207 bad: 208 return; 209 } 210 #else 211 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {} 212 #endif 213 214 /** 215 * ipv6_rearrange_rthdr - rearrange IPv6 routing header 216 * @iph: IPv6 header 217 * @rthdr: routing header 218 * 219 * Rearrange the destination address in @iph and the addresses in @rthdr 220 * so that they appear in the order they will at the final destination. 221 * See Appendix A2 of RFC 2402 for details. 222 */ 223 static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr) 224 { 225 int segments, segments_left; 226 struct in6_addr *addrs; 227 struct in6_addr final_addr; 228 229 segments_left = rthdr->segments_left; 230 if (segments_left == 0) 231 return; 232 rthdr->segments_left = 0; 233 234 /* The value of rthdr->hdrlen has been verified either by the system 235 * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming 236 * packets. So we can assume that it is even and that segments is 237 * greater than or equal to segments_left. 238 * 239 * For the same reason we can assume that this option is of type 0. 240 */ 241 segments = rthdr->hdrlen >> 1; 242 243 addrs = ((struct rt0_hdr *)rthdr)->addr; 244 ipv6_addr_copy(&final_addr, addrs + segments - 1); 245 246 addrs += segments - segments_left; 247 memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs)); 248 249 ipv6_addr_copy(addrs, &iph->daddr); 250 ipv6_addr_copy(&iph->daddr, &final_addr); 251 } 252 253 static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir) 254 { 255 union { 256 struct ipv6hdr *iph; 257 struct ipv6_opt_hdr *opth; 258 struct ipv6_rt_hdr *rth; 259 char *raw; 260 } exthdr = { .iph = iph }; 261 char *end = exthdr.raw + len; 262 int nexthdr = iph->nexthdr; 263 264 exthdr.iph++; 265 266 while (exthdr.raw < end) { 267 switch (nexthdr) { 268 case NEXTHDR_DEST: 269 if (dir == XFRM_POLICY_OUT) 270 ipv6_rearrange_destopt(iph, exthdr.opth); 271 case NEXTHDR_HOP: 272 if (!zero_out_mutable_opts(exthdr.opth)) { 273 LIMIT_NETDEBUG( 274 KERN_WARNING "overrun %sopts\n", 275 nexthdr == NEXTHDR_HOP ? 276 "hop" : "dest"); 277 return -EINVAL; 278 } 279 break; 280 281 case NEXTHDR_ROUTING: 282 ipv6_rearrange_rthdr(iph, exthdr.rth); 283 break; 284 285 default : 286 return 0; 287 } 288 289 nexthdr = exthdr.opth->nexthdr; 290 exthdr.raw += ipv6_optlen(exthdr.opth); 291 } 292 293 return 0; 294 } 295 296 static void ah6_output_done(struct crypto_async_request *base, int err) 297 { 298 int extlen; 299 u8 *iph_base; 300 u8 *icv; 301 struct sk_buff *skb = base->data; 302 struct xfrm_state *x = skb_dst(skb)->xfrm; 303 struct ah_data *ahp = x->data; 304 struct ipv6hdr *top_iph = ipv6_hdr(skb); 305 struct ip_auth_hdr *ah = ip_auth_hdr(skb); 306 struct tmp_ext *iph_ext; 307 308 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr); 309 if (extlen) 310 extlen += sizeof(*iph_ext); 311 312 iph_base = AH_SKB_CB(skb)->tmp; 313 iph_ext = ah_tmp_ext(iph_base); 314 icv = ah_tmp_icv(ahp->ahash, iph_ext, extlen); 315 316 memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 317 memcpy(top_iph, iph_base, IPV6HDR_BASELEN); 318 319 if (extlen) { 320 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 321 memcpy(&top_iph->saddr, iph_ext, extlen); 322 #else 323 memcpy(&top_iph->daddr, iph_ext, extlen); 324 #endif 325 } 326 327 err = ah->nexthdr; 328 329 kfree(AH_SKB_CB(skb)->tmp); 330 xfrm_output_resume(skb, err); 331 } 332 333 static int ah6_output(struct xfrm_state *x, struct sk_buff *skb) 334 { 335 int err; 336 int nfrags; 337 int extlen; 338 u8 *iph_base; 339 u8 *icv; 340 u8 nexthdr; 341 struct sk_buff *trailer; 342 struct crypto_ahash *ahash; 343 struct ahash_request *req; 344 struct scatterlist *sg; 345 struct ipv6hdr *top_iph; 346 struct ip_auth_hdr *ah; 347 struct ah_data *ahp; 348 struct tmp_ext *iph_ext; 349 350 ahp = x->data; 351 ahash = ahp->ahash; 352 353 if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 354 goto out; 355 nfrags = err; 356 357 skb_push(skb, -skb_network_offset(skb)); 358 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr); 359 if (extlen) 360 extlen += sizeof(*iph_ext); 361 362 err = -ENOMEM; 363 iph_base = ah_alloc_tmp(ahash, nfrags, IPV6HDR_BASELEN + extlen); 364 if (!iph_base) 365 goto out; 366 367 iph_ext = ah_tmp_ext(iph_base); 368 icv = ah_tmp_icv(ahash, iph_ext, extlen); 369 req = ah_tmp_req(ahash, icv); 370 sg = ah_req_sg(ahash, req); 371 372 ah = ip_auth_hdr(skb); 373 memset(ah->auth_data, 0, ahp->icv_trunc_len); 374 375 top_iph = ipv6_hdr(skb); 376 top_iph->payload_len = htons(skb->len - sizeof(*top_iph)); 377 378 nexthdr = *skb_mac_header(skb); 379 *skb_mac_header(skb) = IPPROTO_AH; 380 381 /* When there are no extension headers, we only need to save the first 382 * 8 bytes of the base IP header. 383 */ 384 memcpy(iph_base, top_iph, IPV6HDR_BASELEN); 385 386 if (extlen) { 387 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 388 memcpy(iph_ext, &top_iph->saddr, extlen); 389 #else 390 memcpy(iph_ext, &top_iph->daddr, extlen); 391 #endif 392 err = ipv6_clear_mutable_options(top_iph, 393 extlen - sizeof(*iph_ext) + 394 sizeof(*top_iph), 395 XFRM_POLICY_OUT); 396 if (err) 397 goto out_free; 398 } 399 400 ah->nexthdr = nexthdr; 401 402 top_iph->priority = 0; 403 top_iph->flow_lbl[0] = 0; 404 top_iph->flow_lbl[1] = 0; 405 top_iph->flow_lbl[2] = 0; 406 top_iph->hop_limit = 0; 407 408 ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; 409 410 ah->reserved = 0; 411 ah->spi = x->id.spi; 412 ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output); 413 414 sg_init_table(sg, nfrags); 415 skb_to_sgvec(skb, sg, 0, skb->len); 416 417 ahash_request_set_crypt(req, sg, icv, skb->len); 418 ahash_request_set_callback(req, 0, ah6_output_done, skb); 419 420 AH_SKB_CB(skb)->tmp = iph_base; 421 422 err = crypto_ahash_digest(req); 423 if (err) { 424 if (err == -EINPROGRESS) 425 goto out; 426 427 if (err == -EBUSY) 428 err = NET_XMIT_DROP; 429 goto out_free; 430 } 431 432 memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 433 memcpy(top_iph, iph_base, IPV6HDR_BASELEN); 434 435 if (extlen) { 436 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) 437 memcpy(&top_iph->saddr, iph_ext, extlen); 438 #else 439 memcpy(&top_iph->daddr, iph_ext, extlen); 440 #endif 441 } 442 443 out_free: 444 kfree(iph_base); 445 out: 446 return err; 447 } 448 449 static void ah6_input_done(struct crypto_async_request *base, int err) 450 { 451 u8 *auth_data; 452 u8 *icv; 453 u8 *work_iph; 454 struct sk_buff *skb = base->data; 455 struct xfrm_state *x = xfrm_input_state(skb); 456 struct ah_data *ahp = x->data; 457 struct ip_auth_hdr *ah = ip_auth_hdr(skb); 458 int hdr_len = skb_network_header_len(skb); 459 int ah_hlen = (ah->hdrlen + 2) << 2; 460 461 work_iph = AH_SKB_CB(skb)->tmp; 462 auth_data = ah_tmp_auth(work_iph, hdr_len); 463 icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len); 464 465 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 466 if (err) 467 goto out; 468 469 skb->network_header += ah_hlen; 470 memcpy(skb_network_header(skb), work_iph, hdr_len); 471 __skb_pull(skb, ah_hlen + hdr_len); 472 skb_set_transport_header(skb, -hdr_len); 473 474 err = ah->nexthdr; 475 out: 476 kfree(AH_SKB_CB(skb)->tmp); 477 xfrm_input_resume(skb, err); 478 } 479 480 481 482 static int ah6_input(struct xfrm_state *x, struct sk_buff *skb) 483 { 484 /* 485 * Before process AH 486 * [IPv6][Ext1][Ext2][AH][Dest][Payload] 487 * |<-------------->| hdr_len 488 * 489 * To erase AH: 490 * Keeping copy of cleared headers. After AH processing, 491 * Moving the pointer of skb->network_header by using skb_pull as long 492 * as AH header length. Then copy back the copy as long as hdr_len 493 * If destination header following AH exists, copy it into after [Ext2]. 494 * 495 * |<>|[IPv6][Ext1][Ext2][Dest][Payload] 496 * There is offset of AH before IPv6 header after the process. 497 */ 498 499 u8 *auth_data; 500 u8 *icv; 501 u8 *work_iph; 502 struct sk_buff *trailer; 503 struct crypto_ahash *ahash; 504 struct ahash_request *req; 505 struct scatterlist *sg; 506 struct ip_auth_hdr *ah; 507 struct ipv6hdr *ip6h; 508 struct ah_data *ahp; 509 u16 hdr_len; 510 u16 ah_hlen; 511 int nexthdr; 512 int nfrags; 513 int err = -ENOMEM; 514 515 if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr))) 516 goto out; 517 518 /* We are going to _remove_ AH header to keep sockets happy, 519 * so... Later this can change. */ 520 if (skb_cloned(skb) && 521 pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) 522 goto out; 523 524 skb->ip_summed = CHECKSUM_NONE; 525 526 hdr_len = skb_network_header_len(skb); 527 ah = (struct ip_auth_hdr *)skb->data; 528 ahp = x->data; 529 ahash = ahp->ahash; 530 531 nexthdr = ah->nexthdr; 532 ah_hlen = (ah->hdrlen + 2) << 2; 533 534 if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && 535 ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) 536 goto out; 537 538 if (!pskb_may_pull(skb, ah_hlen)) 539 goto out; 540 541 ip6h = ipv6_hdr(skb); 542 543 skb_push(skb, hdr_len); 544 545 if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 546 goto out; 547 nfrags = err; 548 549 work_iph = ah_alloc_tmp(ahash, nfrags, hdr_len + ahp->icv_trunc_len); 550 if (!work_iph) 551 goto out; 552 553 auth_data = ah_tmp_auth(work_iph, hdr_len); 554 icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len); 555 req = ah_tmp_req(ahash, icv); 556 sg = ah_req_sg(ahash, req); 557 558 memcpy(work_iph, ip6h, hdr_len); 559 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); 560 memset(ah->auth_data, 0, ahp->icv_trunc_len); 561 562 if (ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN)) 563 goto out_free; 564 565 ip6h->priority = 0; 566 ip6h->flow_lbl[0] = 0; 567 ip6h->flow_lbl[1] = 0; 568 ip6h->flow_lbl[2] = 0; 569 ip6h->hop_limit = 0; 570 571 sg_init_table(sg, nfrags); 572 skb_to_sgvec(skb, sg, 0, skb->len); 573 574 ahash_request_set_crypt(req, sg, icv, skb->len); 575 ahash_request_set_callback(req, 0, ah6_input_done, skb); 576 577 AH_SKB_CB(skb)->tmp = work_iph; 578 579 err = crypto_ahash_digest(req); 580 if (err) { 581 if (err == -EINPROGRESS) 582 goto out; 583 584 if (err == -EBUSY) 585 err = NET_XMIT_DROP; 586 goto out_free; 587 } 588 589 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 590 if (err) 591 goto out_free; 592 593 skb->network_header += ah_hlen; 594 memcpy(skb_network_header(skb), work_iph, hdr_len); 595 skb->transport_header = skb->network_header; 596 __skb_pull(skb, ah_hlen + hdr_len); 597 598 err = nexthdr; 599 600 out_free: 601 kfree(work_iph); 602 out: 603 return err; 604 } 605 606 static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 607 u8 type, u8 code, int offset, __be32 info) 608 { 609 struct net *net = dev_net(skb->dev); 610 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data; 611 struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset); 612 struct xfrm_state *x; 613 614 if (type != ICMPV6_DEST_UNREACH && 615 type != ICMPV6_PKT_TOOBIG) 616 return; 617 618 x = xfrm_state_lookup(net, skb->mark, (xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6); 619 if (!x) 620 return; 621 622 NETDEBUG(KERN_DEBUG "pmtu discovery on SA AH/%08x/%pI6\n", 623 ntohl(ah->spi), &iph->daddr); 624 625 xfrm_state_put(x); 626 } 627 628 static int ah6_init_state(struct xfrm_state *x) 629 { 630 struct ah_data *ahp = NULL; 631 struct xfrm_algo_desc *aalg_desc; 632 struct crypto_ahash *ahash; 633 634 if (!x->aalg) 635 goto error; 636 637 if (x->encap) 638 goto error; 639 640 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); 641 if (ahp == NULL) 642 return -ENOMEM; 643 644 ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); 645 if (IS_ERR(ahash)) 646 goto error; 647 648 ahp->ahash = ahash; 649 if (crypto_ahash_setkey(ahash, x->aalg->alg_key, 650 (x->aalg->alg_key_len + 7) / 8)) 651 goto error; 652 653 /* 654 * Lookup the algorithm description maintained by xfrm_algo, 655 * verify crypto transform properties, and store information 656 * we need for AH processing. This lookup cannot fail here 657 * after a successful crypto_alloc_hash(). 658 */ 659 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 660 BUG_ON(!aalg_desc); 661 662 if (aalg_desc->uinfo.auth.icv_fullbits/8 != 663 crypto_ahash_digestsize(ahash)) { 664 printk(KERN_INFO "AH: %s digestsize %u != %hu\n", 665 x->aalg->alg_name, crypto_ahash_digestsize(ahash), 666 aalg_desc->uinfo.auth.icv_fullbits/8); 667 goto error; 668 } 669 670 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; 671 ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; 672 673 BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN); 674 675 x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + 676 ahp->icv_trunc_len); 677 switch (x->props.mode) { 678 case XFRM_MODE_BEET: 679 case XFRM_MODE_TRANSPORT: 680 break; 681 case XFRM_MODE_TUNNEL: 682 x->props.header_len += sizeof(struct ipv6hdr); 683 break; 684 default: 685 goto error; 686 } 687 x->data = ahp; 688 689 return 0; 690 691 error: 692 if (ahp) { 693 crypto_free_ahash(ahp->ahash); 694 kfree(ahp); 695 } 696 return -EINVAL; 697 } 698 699 static void ah6_destroy(struct xfrm_state *x) 700 { 701 struct ah_data *ahp = x->data; 702 703 if (!ahp) 704 return; 705 706 crypto_free_ahash(ahp->ahash); 707 kfree(ahp); 708 } 709 710 static const struct xfrm_type ah6_type = 711 { 712 .description = "AH6", 713 .owner = THIS_MODULE, 714 .proto = IPPROTO_AH, 715 .flags = XFRM_TYPE_REPLAY_PROT, 716 .init_state = ah6_init_state, 717 .destructor = ah6_destroy, 718 .input = ah6_input, 719 .output = ah6_output, 720 .hdr_offset = xfrm6_find_1stfragopt, 721 }; 722 723 static const struct inet6_protocol ah6_protocol = { 724 .handler = xfrm6_rcv, 725 .err_handler = ah6_err, 726 .flags = INET6_PROTO_NOPOLICY, 727 }; 728 729 static int __init ah6_init(void) 730 { 731 if (xfrm_register_type(&ah6_type, AF_INET6) < 0) { 732 printk(KERN_INFO "ipv6 ah init: can't add xfrm type\n"); 733 return -EAGAIN; 734 } 735 736 if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) { 737 printk(KERN_INFO "ipv6 ah init: can't add protocol\n"); 738 xfrm_unregister_type(&ah6_type, AF_INET6); 739 return -EAGAIN; 740 } 741 742 return 0; 743 } 744 745 static void __exit ah6_fini(void) 746 { 747 if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0) 748 printk(KERN_INFO "ipv6 ah close: can't remove protocol\n"); 749 750 if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0) 751 printk(KERN_INFO "ipv6 ah close: can't remove xfrm type\n"); 752 753 } 754 755 module_init(ah6_init); 756 module_exit(ah6_fini); 757 758 MODULE_LICENSE("GPL"); 759 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH); 760