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 #define pr_fmt(fmt) "IPv6: " fmt 28 29 #include <crypto/hash.h> 30 #include <linux/module.h> 31 #include <linux/slab.h> 32 #include <net/ip.h> 33 #include <net/ah.h> 34 #include <linux/crypto.h> 35 #include <linux/pfkeyv2.h> 36 #include <linux/string.h> 37 #include <linux/scatterlist.h> 38 #include <net/ip6_route.h> 39 #include <net/icmp.h> 40 #include <net/ipv6.h> 41 #include <net/protocol.h> 42 #include <net/xfrm.h> 43 44 #define IPV6HDR_BASELEN 8 45 46 struct tmp_ext { 47 #if IS_ENABLED(CONFIG_IPV6_MIP6) 48 struct in6_addr saddr; 49 #endif 50 struct in6_addr daddr; 51 char hdrs[0]; 52 }; 53 54 struct ah_skb_cb { 55 struct xfrm_skb_cb xfrm; 56 void *tmp; 57 }; 58 59 #define AH_SKB_CB(__skb) ((struct ah_skb_cb *)&((__skb)->cb[0])) 60 61 static void *ah_alloc_tmp(struct crypto_ahash *ahash, int nfrags, 62 unsigned int size) 63 { 64 unsigned int len; 65 66 len = size + crypto_ahash_digestsize(ahash) + 67 (crypto_ahash_alignmask(ahash) & 68 ~(crypto_tfm_ctx_alignment() - 1)); 69 70 len = ALIGN(len, crypto_tfm_ctx_alignment()); 71 72 len += sizeof(struct ahash_request) + crypto_ahash_reqsize(ahash); 73 len = ALIGN(len, __alignof__(struct scatterlist)); 74 75 len += sizeof(struct scatterlist) * nfrags; 76 77 return kmalloc(len, GFP_ATOMIC); 78 } 79 80 static inline struct tmp_ext *ah_tmp_ext(void *base) 81 { 82 return base + IPV6HDR_BASELEN; 83 } 84 85 static inline u8 *ah_tmp_auth(u8 *tmp, unsigned int offset) 86 { 87 return tmp + offset; 88 } 89 90 static inline u8 *ah_tmp_icv(struct crypto_ahash *ahash, void *tmp, 91 unsigned int offset) 92 { 93 return PTR_ALIGN((u8 *)tmp + offset, crypto_ahash_alignmask(ahash) + 1); 94 } 95 96 static inline struct ahash_request *ah_tmp_req(struct crypto_ahash *ahash, 97 u8 *icv) 98 { 99 struct ahash_request *req; 100 101 req = (void *)PTR_ALIGN(icv + crypto_ahash_digestsize(ahash), 102 crypto_tfm_ctx_alignment()); 103 104 ahash_request_set_tfm(req, ahash); 105 106 return req; 107 } 108 109 static inline struct scatterlist *ah_req_sg(struct crypto_ahash *ahash, 110 struct ahash_request *req) 111 { 112 return (void *)ALIGN((unsigned long)(req + 1) + 113 crypto_ahash_reqsize(ahash), 114 __alignof__(struct scatterlist)); 115 } 116 117 static bool zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr) 118 { 119 u8 *opt = (u8 *)opthdr; 120 int len = ipv6_optlen(opthdr); 121 int off = 0; 122 int optlen = 0; 123 124 off += 2; 125 len -= 2; 126 127 while (len > 0) { 128 129 switch (opt[off]) { 130 131 case IPV6_TLV_PAD1: 132 optlen = 1; 133 break; 134 default: 135 if (len < 2) 136 goto bad; 137 optlen = opt[off+1]+2; 138 if (len < optlen) 139 goto bad; 140 if (opt[off] & 0x20) 141 memset(&opt[off+2], 0, opt[off+1]); 142 break; 143 } 144 145 off += optlen; 146 len -= optlen; 147 } 148 if (len == 0) 149 return true; 150 151 bad: 152 return false; 153 } 154 155 #if IS_ENABLED(CONFIG_IPV6_MIP6) 156 /** 157 * ipv6_rearrange_destopt - rearrange IPv6 destination options header 158 * @iph: IPv6 header 159 * @destopt: destionation options header 160 */ 161 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) 162 { 163 u8 *opt = (u8 *)destopt; 164 int len = ipv6_optlen(destopt); 165 int off = 0; 166 int optlen = 0; 167 168 off += 2; 169 len -= 2; 170 171 while (len > 0) { 172 173 switch (opt[off]) { 174 175 case IPV6_TLV_PAD1: 176 optlen = 1; 177 break; 178 default: 179 if (len < 2) 180 goto bad; 181 optlen = opt[off+1]+2; 182 if (len < optlen) 183 goto bad; 184 185 /* Rearrange the source address in @iph and the 186 * addresses in home address option for final source. 187 * See 11.3.2 of RFC 3775 for details. 188 */ 189 if (opt[off] == IPV6_TLV_HAO) { 190 struct in6_addr final_addr; 191 struct ipv6_destopt_hao *hao; 192 193 hao = (struct ipv6_destopt_hao *)&opt[off]; 194 if (hao->length != sizeof(hao->addr)) { 195 net_warn_ratelimited("destopt hao: invalid header length: %u\n", 196 hao->length); 197 goto bad; 198 } 199 final_addr = hao->addr; 200 hao->addr = iph->saddr; 201 iph->saddr = final_addr; 202 } 203 break; 204 } 205 206 off += optlen; 207 len -= optlen; 208 } 209 /* Note: ok if len == 0 */ 210 bad: 211 return; 212 } 213 #else 214 static void ipv6_rearrange_destopt(struct ipv6hdr *iph, struct ipv6_opt_hdr *destopt) {} 215 #endif 216 217 /** 218 * ipv6_rearrange_rthdr - rearrange IPv6 routing header 219 * @iph: IPv6 header 220 * @rthdr: routing header 221 * 222 * Rearrange the destination address in @iph and the addresses in @rthdr 223 * so that they appear in the order they will at the final destination. 224 * See Appendix A2 of RFC 2402 for details. 225 */ 226 static void ipv6_rearrange_rthdr(struct ipv6hdr *iph, struct ipv6_rt_hdr *rthdr) 227 { 228 int segments, segments_left; 229 struct in6_addr *addrs; 230 struct in6_addr final_addr; 231 232 segments_left = rthdr->segments_left; 233 if (segments_left == 0) 234 return; 235 rthdr->segments_left = 0; 236 237 /* The value of rthdr->hdrlen has been verified either by the system 238 * call if it is locally generated, or by ipv6_rthdr_rcv() for incoming 239 * packets. So we can assume that it is even and that segments is 240 * greater than or equal to segments_left. 241 * 242 * For the same reason we can assume that this option is of type 0. 243 */ 244 segments = rthdr->hdrlen >> 1; 245 246 addrs = ((struct rt0_hdr *)rthdr)->addr; 247 final_addr = addrs[segments - 1]; 248 249 addrs += segments - segments_left; 250 memmove(addrs + 1, addrs, (segments_left - 1) * sizeof(*addrs)); 251 252 addrs[0] = iph->daddr; 253 iph->daddr = final_addr; 254 } 255 256 static int ipv6_clear_mutable_options(struct ipv6hdr *iph, int len, int dir) 257 { 258 union { 259 struct ipv6hdr *iph; 260 struct ipv6_opt_hdr *opth; 261 struct ipv6_rt_hdr *rth; 262 char *raw; 263 } exthdr = { .iph = iph }; 264 char *end = exthdr.raw + len; 265 int nexthdr = iph->nexthdr; 266 267 exthdr.iph++; 268 269 while (exthdr.raw < end) { 270 switch (nexthdr) { 271 case NEXTHDR_DEST: 272 if (dir == XFRM_POLICY_OUT) 273 ipv6_rearrange_destopt(iph, exthdr.opth); 274 case NEXTHDR_HOP: 275 if (!zero_out_mutable_opts(exthdr.opth)) { 276 LIMIT_NETDEBUG( 277 KERN_WARNING "overrun %sopts\n", 278 nexthdr == NEXTHDR_HOP ? 279 "hop" : "dest"); 280 return -EINVAL; 281 } 282 break; 283 284 case NEXTHDR_ROUTING: 285 ipv6_rearrange_rthdr(iph, exthdr.rth); 286 break; 287 288 default : 289 return 0; 290 } 291 292 nexthdr = exthdr.opth->nexthdr; 293 exthdr.raw += ipv6_optlen(exthdr.opth); 294 } 295 296 return 0; 297 } 298 299 static void ah6_output_done(struct crypto_async_request *base, int err) 300 { 301 int extlen; 302 u8 *iph_base; 303 u8 *icv; 304 struct sk_buff *skb = base->data; 305 struct xfrm_state *x = skb_dst(skb)->xfrm; 306 struct ah_data *ahp = x->data; 307 struct ipv6hdr *top_iph = ipv6_hdr(skb); 308 struct ip_auth_hdr *ah = ip_auth_hdr(skb); 309 struct tmp_ext *iph_ext; 310 311 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr); 312 if (extlen) 313 extlen += sizeof(*iph_ext); 314 315 iph_base = AH_SKB_CB(skb)->tmp; 316 iph_ext = ah_tmp_ext(iph_base); 317 icv = ah_tmp_icv(ahp->ahash, iph_ext, extlen); 318 319 memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 320 memcpy(top_iph, iph_base, IPV6HDR_BASELEN); 321 322 if (extlen) { 323 #if IS_ENABLED(CONFIG_IPV6_MIP6) 324 memcpy(&top_iph->saddr, iph_ext, extlen); 325 #else 326 memcpy(&top_iph->daddr, iph_ext, extlen); 327 #endif 328 } 329 330 kfree(AH_SKB_CB(skb)->tmp); 331 xfrm_output_resume(skb, err); 332 } 333 334 static int ah6_output(struct xfrm_state *x, struct sk_buff *skb) 335 { 336 int err; 337 int nfrags; 338 int extlen; 339 u8 *iph_base; 340 u8 *icv; 341 u8 nexthdr; 342 struct sk_buff *trailer; 343 struct crypto_ahash *ahash; 344 struct ahash_request *req; 345 struct scatterlist *sg; 346 struct ipv6hdr *top_iph; 347 struct ip_auth_hdr *ah; 348 struct ah_data *ahp; 349 struct tmp_ext *iph_ext; 350 351 ahp = x->data; 352 ahash = ahp->ahash; 353 354 if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 355 goto out; 356 nfrags = err; 357 358 skb_push(skb, -skb_network_offset(skb)); 359 extlen = skb_network_header_len(skb) - sizeof(struct ipv6hdr); 360 if (extlen) 361 extlen += sizeof(*iph_ext); 362 363 err = -ENOMEM; 364 iph_base = ah_alloc_tmp(ahash, nfrags, IPV6HDR_BASELEN + extlen); 365 if (!iph_base) 366 goto out; 367 368 iph_ext = ah_tmp_ext(iph_base); 369 icv = ah_tmp_icv(ahash, iph_ext, extlen); 370 req = ah_tmp_req(ahash, icv); 371 sg = ah_req_sg(ahash, req); 372 373 ah = ip_auth_hdr(skb); 374 memset(ah->auth_data, 0, ahp->icv_trunc_len); 375 376 top_iph = ipv6_hdr(skb); 377 top_iph->payload_len = htons(skb->len - sizeof(*top_iph)); 378 379 nexthdr = *skb_mac_header(skb); 380 *skb_mac_header(skb) = IPPROTO_AH; 381 382 /* When there are no extension headers, we only need to save the first 383 * 8 bytes of the base IP header. 384 */ 385 memcpy(iph_base, top_iph, IPV6HDR_BASELEN); 386 387 if (extlen) { 388 #if IS_ENABLED(CONFIG_IPV6_MIP6) 389 memcpy(iph_ext, &top_iph->saddr, extlen); 390 #else 391 memcpy(iph_ext, &top_iph->daddr, extlen); 392 #endif 393 err = ipv6_clear_mutable_options(top_iph, 394 extlen - sizeof(*iph_ext) + 395 sizeof(*top_iph), 396 XFRM_POLICY_OUT); 397 if (err) 398 goto out_free; 399 } 400 401 ah->nexthdr = nexthdr; 402 403 top_iph->priority = 0; 404 top_iph->flow_lbl[0] = 0; 405 top_iph->flow_lbl[1] = 0; 406 top_iph->flow_lbl[2] = 0; 407 top_iph->hop_limit = 0; 408 409 ah->hdrlen = (XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len) >> 2) - 2; 410 411 ah->reserved = 0; 412 ah->spi = x->id.spi; 413 ah->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 414 415 sg_init_table(sg, nfrags); 416 skb_to_sgvec(skb, sg, 0, skb->len); 417 418 ahash_request_set_crypt(req, sg, icv, skb->len); 419 ahash_request_set_callback(req, 0, ah6_output_done, skb); 420 421 AH_SKB_CB(skb)->tmp = iph_base; 422 423 err = crypto_ahash_digest(req); 424 if (err) { 425 if (err == -EINPROGRESS) 426 goto out; 427 428 if (err == -EBUSY) 429 err = NET_XMIT_DROP; 430 goto out_free; 431 } 432 433 memcpy(ah->auth_data, icv, ahp->icv_trunc_len); 434 memcpy(top_iph, iph_base, IPV6HDR_BASELEN); 435 436 if (extlen) { 437 #if IS_ENABLED(CONFIG_IPV6_MIP6) 438 memcpy(&top_iph->saddr, iph_ext, extlen); 439 #else 440 memcpy(&top_iph->daddr, iph_ext, extlen); 441 #endif 442 } 443 444 out_free: 445 kfree(iph_base); 446 out: 447 return err; 448 } 449 450 static void ah6_input_done(struct crypto_async_request *base, int err) 451 { 452 u8 *auth_data; 453 u8 *icv; 454 u8 *work_iph; 455 struct sk_buff *skb = base->data; 456 struct xfrm_state *x = xfrm_input_state(skb); 457 struct ah_data *ahp = x->data; 458 struct ip_auth_hdr *ah = ip_auth_hdr(skb); 459 int hdr_len = skb_network_header_len(skb); 460 int ah_hlen = (ah->hdrlen + 2) << 2; 461 462 work_iph = AH_SKB_CB(skb)->tmp; 463 auth_data = ah_tmp_auth(work_iph, hdr_len); 464 icv = ah_tmp_icv(ahp->ahash, auth_data, ahp->icv_trunc_len); 465 466 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 467 if (err) 468 goto out; 469 470 err = ah->nexthdr; 471 472 skb->network_header += ah_hlen; 473 memcpy(skb_network_header(skb), work_iph, hdr_len); 474 __skb_pull(skb, ah_hlen + hdr_len); 475 if (x->props.mode == XFRM_MODE_TUNNEL) 476 skb_reset_transport_header(skb); 477 else 478 skb_set_transport_header(skb, -hdr_len); 479 out: 480 kfree(AH_SKB_CB(skb)->tmp); 481 xfrm_input_resume(skb, err); 482 } 483 484 485 486 static int ah6_input(struct xfrm_state *x, struct sk_buff *skb) 487 { 488 /* 489 * Before process AH 490 * [IPv6][Ext1][Ext2][AH][Dest][Payload] 491 * |<-------------->| hdr_len 492 * 493 * To erase AH: 494 * Keeping copy of cleared headers. After AH processing, 495 * Moving the pointer of skb->network_header by using skb_pull as long 496 * as AH header length. Then copy back the copy as long as hdr_len 497 * If destination header following AH exists, copy it into after [Ext2]. 498 * 499 * |<>|[IPv6][Ext1][Ext2][Dest][Payload] 500 * There is offset of AH before IPv6 header after the process. 501 */ 502 503 u8 *auth_data; 504 u8 *icv; 505 u8 *work_iph; 506 struct sk_buff *trailer; 507 struct crypto_ahash *ahash; 508 struct ahash_request *req; 509 struct scatterlist *sg; 510 struct ip_auth_hdr *ah; 511 struct ipv6hdr *ip6h; 512 struct ah_data *ahp; 513 u16 hdr_len; 514 u16 ah_hlen; 515 int nexthdr; 516 int nfrags; 517 int err = -ENOMEM; 518 519 if (!pskb_may_pull(skb, sizeof(struct ip_auth_hdr))) 520 goto out; 521 522 /* We are going to _remove_ AH header to keep sockets happy, 523 * so... Later this can change. */ 524 if (skb_unclone(skb, GFP_ATOMIC)) 525 goto out; 526 527 skb->ip_summed = CHECKSUM_NONE; 528 529 hdr_len = skb_network_header_len(skb); 530 ah = (struct ip_auth_hdr *)skb->data; 531 ahp = x->data; 532 ahash = ahp->ahash; 533 534 nexthdr = ah->nexthdr; 535 ah_hlen = (ah->hdrlen + 2) << 2; 536 537 if (ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_full_len) && 538 ah_hlen != XFRM_ALIGN8(sizeof(*ah) + ahp->icv_trunc_len)) 539 goto out; 540 541 if (!pskb_may_pull(skb, ah_hlen)) 542 goto out; 543 544 545 if ((err = skb_cow_data(skb, 0, &trailer)) < 0) 546 goto out; 547 nfrags = err; 548 549 ah = (struct ip_auth_hdr *)skb->data; 550 ip6h = ipv6_hdr(skb); 551 552 skb_push(skb, hdr_len); 553 554 work_iph = ah_alloc_tmp(ahash, nfrags, hdr_len + ahp->icv_trunc_len); 555 if (!work_iph) 556 goto out; 557 558 auth_data = ah_tmp_auth(work_iph, hdr_len); 559 icv = ah_tmp_icv(ahash, auth_data, ahp->icv_trunc_len); 560 req = ah_tmp_req(ahash, icv); 561 sg = ah_req_sg(ahash, req); 562 563 memcpy(work_iph, ip6h, hdr_len); 564 memcpy(auth_data, ah->auth_data, ahp->icv_trunc_len); 565 memset(ah->auth_data, 0, ahp->icv_trunc_len); 566 567 if (ipv6_clear_mutable_options(ip6h, hdr_len, XFRM_POLICY_IN)) 568 goto out_free; 569 570 ip6h->priority = 0; 571 ip6h->flow_lbl[0] = 0; 572 ip6h->flow_lbl[1] = 0; 573 ip6h->flow_lbl[2] = 0; 574 ip6h->hop_limit = 0; 575 576 sg_init_table(sg, nfrags); 577 skb_to_sgvec(skb, sg, 0, skb->len); 578 579 ahash_request_set_crypt(req, sg, icv, skb->len); 580 ahash_request_set_callback(req, 0, ah6_input_done, skb); 581 582 AH_SKB_CB(skb)->tmp = work_iph; 583 584 err = crypto_ahash_digest(req); 585 if (err) { 586 if (err == -EINPROGRESS) 587 goto out; 588 589 goto out_free; 590 } 591 592 err = memcmp(icv, auth_data, ahp->icv_trunc_len) ? -EBADMSG: 0; 593 if (err) 594 goto out_free; 595 596 skb->network_header += ah_hlen; 597 memcpy(skb_network_header(skb), work_iph, hdr_len); 598 __skb_pull(skb, ah_hlen + hdr_len); 599 600 if (x->props.mode == XFRM_MODE_TUNNEL) 601 skb_reset_transport_header(skb); 602 else 603 skb_set_transport_header(skb, -hdr_len); 604 605 err = nexthdr; 606 607 out_free: 608 kfree(work_iph); 609 out: 610 return err; 611 } 612 613 static void ah6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 614 u8 type, u8 code, int offset, __be32 info) 615 { 616 struct net *net = dev_net(skb->dev); 617 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data; 618 struct ip_auth_hdr *ah = (struct ip_auth_hdr*)(skb->data+offset); 619 struct xfrm_state *x; 620 621 if (type != ICMPV6_DEST_UNREACH && 622 type != ICMPV6_PKT_TOOBIG && 623 type != NDISC_REDIRECT) 624 return; 625 626 x = xfrm_state_lookup(net, skb->mark, (xfrm_address_t *)&iph->daddr, ah->spi, IPPROTO_AH, AF_INET6); 627 if (!x) 628 return; 629 630 if (type == NDISC_REDIRECT) 631 ip6_redirect(skb, net, 0, 0); 632 else 633 ip6_update_pmtu(skb, net, info, 0, 0); 634 xfrm_state_put(x); 635 } 636 637 static int ah6_init_state(struct xfrm_state *x) 638 { 639 struct ah_data *ahp = NULL; 640 struct xfrm_algo_desc *aalg_desc; 641 struct crypto_ahash *ahash; 642 643 if (!x->aalg) 644 goto error; 645 646 if (x->encap) 647 goto error; 648 649 ahp = kzalloc(sizeof(*ahp), GFP_KERNEL); 650 if (ahp == NULL) 651 return -ENOMEM; 652 653 ahash = crypto_alloc_ahash(x->aalg->alg_name, 0, 0); 654 if (IS_ERR(ahash)) 655 goto error; 656 657 ahp->ahash = ahash; 658 if (crypto_ahash_setkey(ahash, x->aalg->alg_key, 659 (x->aalg->alg_key_len + 7) / 8)) 660 goto error; 661 662 /* 663 * Lookup the algorithm description maintained by xfrm_algo, 664 * verify crypto transform properties, and store information 665 * we need for AH processing. This lookup cannot fail here 666 * after a successful crypto_alloc_hash(). 667 */ 668 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 669 BUG_ON(!aalg_desc); 670 671 if (aalg_desc->uinfo.auth.icv_fullbits/8 != 672 crypto_ahash_digestsize(ahash)) { 673 pr_info("AH: %s digestsize %u != %hu\n", 674 x->aalg->alg_name, crypto_ahash_digestsize(ahash), 675 aalg_desc->uinfo.auth.icv_fullbits/8); 676 goto error; 677 } 678 679 ahp->icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; 680 ahp->icv_trunc_len = x->aalg->alg_trunc_len/8; 681 682 BUG_ON(ahp->icv_trunc_len > MAX_AH_AUTH_LEN); 683 684 x->props.header_len = XFRM_ALIGN8(sizeof(struct ip_auth_hdr) + 685 ahp->icv_trunc_len); 686 switch (x->props.mode) { 687 case XFRM_MODE_BEET: 688 case XFRM_MODE_TRANSPORT: 689 break; 690 case XFRM_MODE_TUNNEL: 691 x->props.header_len += sizeof(struct ipv6hdr); 692 break; 693 default: 694 goto error; 695 } 696 x->data = ahp; 697 698 return 0; 699 700 error: 701 if (ahp) { 702 crypto_free_ahash(ahp->ahash); 703 kfree(ahp); 704 } 705 return -EINVAL; 706 } 707 708 static void ah6_destroy(struct xfrm_state *x) 709 { 710 struct ah_data *ahp = x->data; 711 712 if (!ahp) 713 return; 714 715 crypto_free_ahash(ahp->ahash); 716 kfree(ahp); 717 } 718 719 static const struct xfrm_type ah6_type = 720 { 721 .description = "AH6", 722 .owner = THIS_MODULE, 723 .proto = IPPROTO_AH, 724 .flags = XFRM_TYPE_REPLAY_PROT, 725 .init_state = ah6_init_state, 726 .destructor = ah6_destroy, 727 .input = ah6_input, 728 .output = ah6_output, 729 .hdr_offset = xfrm6_find_1stfragopt, 730 }; 731 732 static const struct inet6_protocol ah6_protocol = { 733 .handler = xfrm6_rcv, 734 .err_handler = ah6_err, 735 .flags = INET6_PROTO_NOPOLICY, 736 }; 737 738 static int __init ah6_init(void) 739 { 740 if (xfrm_register_type(&ah6_type, AF_INET6) < 0) { 741 pr_info("%s: can't add xfrm type\n", __func__); 742 return -EAGAIN; 743 } 744 745 if (inet6_add_protocol(&ah6_protocol, IPPROTO_AH) < 0) { 746 pr_info("%s: can't add protocol\n", __func__); 747 xfrm_unregister_type(&ah6_type, AF_INET6); 748 return -EAGAIN; 749 } 750 751 return 0; 752 } 753 754 static void __exit ah6_fini(void) 755 { 756 if (inet6_del_protocol(&ah6_protocol, IPPROTO_AH) < 0) 757 pr_info("%s: can't remove protocol\n", __func__); 758 759 if (xfrm_unregister_type(&ah6_type, AF_INET6) < 0) 760 pr_info("%s: can't remove xfrm type\n", __func__); 761 762 } 763 764 module_init(ah6_init); 765 module_exit(ah6_fini); 766 767 MODULE_LICENSE("GPL"); 768 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_AH); 769