1 #define pr_fmt(fmt) "IPsec: " fmt 2 3 #include <crypto/aead.h> 4 #include <crypto/authenc.h> 5 #include <linux/err.h> 6 #include <linux/module.h> 7 #include <net/ip.h> 8 #include <net/xfrm.h> 9 #include <net/esp.h> 10 #include <linux/scatterlist.h> 11 #include <linux/kernel.h> 12 #include <linux/pfkeyv2.h> 13 #include <linux/rtnetlink.h> 14 #include <linux/slab.h> 15 #include <linux/spinlock.h> 16 #include <linux/in6.h> 17 #include <net/icmp.h> 18 #include <net/protocol.h> 19 #include <net/udp.h> 20 21 struct esp_skb_cb { 22 struct xfrm_skb_cb xfrm; 23 void *tmp; 24 }; 25 26 #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) 27 28 static u32 esp4_get_mtu(struct xfrm_state *x, int mtu); 29 30 /* 31 * Allocate an AEAD request structure with extra space for SG and IV. 32 * 33 * For alignment considerations the IV is placed at the front, followed 34 * by the request and finally the SG list. 35 * 36 * TODO: Use spare space in skb for this where possible. 37 */ 38 static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqhilen) 39 { 40 unsigned int len; 41 42 len = seqhilen; 43 44 len += crypto_aead_ivsize(aead); 45 46 if (len) { 47 len += crypto_aead_alignmask(aead) & 48 ~(crypto_tfm_ctx_alignment() - 1); 49 len = ALIGN(len, crypto_tfm_ctx_alignment()); 50 } 51 52 len += sizeof(struct aead_givcrypt_request) + crypto_aead_reqsize(aead); 53 len = ALIGN(len, __alignof__(struct scatterlist)); 54 55 len += sizeof(struct scatterlist) * nfrags; 56 57 return kmalloc(len, GFP_ATOMIC); 58 } 59 60 static inline __be32 *esp_tmp_seqhi(void *tmp) 61 { 62 return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); 63 } 64 static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) 65 { 66 return crypto_aead_ivsize(aead) ? 67 PTR_ALIGN((u8 *)tmp + seqhilen, 68 crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; 69 } 70 71 static inline struct aead_givcrypt_request *esp_tmp_givreq( 72 struct crypto_aead *aead, u8 *iv) 73 { 74 struct aead_givcrypt_request *req; 75 76 req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), 77 crypto_tfm_ctx_alignment()); 78 aead_givcrypt_set_tfm(req, aead); 79 return req; 80 } 81 82 static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) 83 { 84 struct aead_request *req; 85 86 req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), 87 crypto_tfm_ctx_alignment()); 88 aead_request_set_tfm(req, aead); 89 return req; 90 } 91 92 static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, 93 struct aead_request *req) 94 { 95 return (void *)ALIGN((unsigned long)(req + 1) + 96 crypto_aead_reqsize(aead), 97 __alignof__(struct scatterlist)); 98 } 99 100 static inline struct scatterlist *esp_givreq_sg( 101 struct crypto_aead *aead, struct aead_givcrypt_request *req) 102 { 103 return (void *)ALIGN((unsigned long)(req + 1) + 104 crypto_aead_reqsize(aead), 105 __alignof__(struct scatterlist)); 106 } 107 108 static void esp_output_done(struct crypto_async_request *base, int err) 109 { 110 struct sk_buff *skb = base->data; 111 112 kfree(ESP_SKB_CB(skb)->tmp); 113 xfrm_output_resume(skb, err); 114 } 115 116 static int esp_output(struct xfrm_state *x, struct sk_buff *skb) 117 { 118 int err; 119 struct ip_esp_hdr *esph; 120 struct crypto_aead *aead; 121 struct aead_givcrypt_request *req; 122 struct scatterlist *sg; 123 struct scatterlist *asg; 124 struct sk_buff *trailer; 125 void *tmp; 126 u8 *iv; 127 u8 *tail; 128 int blksize; 129 int clen; 130 int alen; 131 int plen; 132 int tfclen; 133 int nfrags; 134 int assoclen; 135 int sglists; 136 int seqhilen; 137 __be32 *seqhi; 138 139 /* skb is pure payload to encrypt */ 140 141 aead = x->data; 142 alen = crypto_aead_authsize(aead); 143 144 tfclen = 0; 145 if (x->tfcpad) { 146 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); 147 u32 padto; 148 149 padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached)); 150 if (skb->len < padto) 151 tfclen = padto - skb->len; 152 } 153 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 154 clen = ALIGN(skb->len + 2 + tfclen, blksize); 155 plen = clen - skb->len - tfclen; 156 157 err = skb_cow_data(skb, tfclen + plen + alen, &trailer); 158 if (err < 0) 159 goto error; 160 nfrags = err; 161 162 assoclen = sizeof(*esph); 163 sglists = 1; 164 seqhilen = 0; 165 166 if (x->props.flags & XFRM_STATE_ESN) { 167 sglists += 2; 168 seqhilen += sizeof(__be32); 169 assoclen += seqhilen; 170 } 171 172 tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); 173 if (!tmp) { 174 err = -ENOMEM; 175 goto error; 176 } 177 178 seqhi = esp_tmp_seqhi(tmp); 179 iv = esp_tmp_iv(aead, tmp, seqhilen); 180 req = esp_tmp_givreq(aead, iv); 181 asg = esp_givreq_sg(aead, req); 182 sg = asg + sglists; 183 184 /* Fill padding... */ 185 tail = skb_tail_pointer(trailer); 186 if (tfclen) { 187 memset(tail, 0, tfclen); 188 tail += tfclen; 189 } 190 do { 191 int i; 192 for (i = 0; i < plen - 2; i++) 193 tail[i] = i + 1; 194 } while (0); 195 tail[plen - 2] = plen - 2; 196 tail[plen - 1] = *skb_mac_header(skb); 197 pskb_put(skb, trailer, clen - skb->len + alen); 198 199 skb_push(skb, -skb_network_offset(skb)); 200 esph = ip_esp_hdr(skb); 201 *skb_mac_header(skb) = IPPROTO_ESP; 202 203 /* this is non-NULL only with UDP Encapsulation */ 204 if (x->encap) { 205 struct xfrm_encap_tmpl *encap = x->encap; 206 struct udphdr *uh; 207 __be32 *udpdata32; 208 __be16 sport, dport; 209 int encap_type; 210 211 spin_lock_bh(&x->lock); 212 sport = encap->encap_sport; 213 dport = encap->encap_dport; 214 encap_type = encap->encap_type; 215 spin_unlock_bh(&x->lock); 216 217 uh = (struct udphdr *)esph; 218 uh->source = sport; 219 uh->dest = dport; 220 uh->len = htons(skb->len - skb_transport_offset(skb)); 221 uh->check = 0; 222 223 switch (encap_type) { 224 default: 225 case UDP_ENCAP_ESPINUDP: 226 esph = (struct ip_esp_hdr *)(uh + 1); 227 break; 228 case UDP_ENCAP_ESPINUDP_NON_IKE: 229 udpdata32 = (__be32 *)(uh + 1); 230 udpdata32[0] = udpdata32[1] = 0; 231 esph = (struct ip_esp_hdr *)(udpdata32 + 2); 232 break; 233 } 234 235 *skb_mac_header(skb) = IPPROTO_UDP; 236 } 237 238 esph->spi = x->id.spi; 239 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 240 241 sg_init_table(sg, nfrags); 242 skb_to_sgvec(skb, sg, 243 esph->enc_data + crypto_aead_ivsize(aead) - skb->data, 244 clen + alen); 245 246 if ((x->props.flags & XFRM_STATE_ESN)) { 247 sg_init_table(asg, 3); 248 sg_set_buf(asg, &esph->spi, sizeof(__be32)); 249 *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); 250 sg_set_buf(asg + 1, seqhi, seqhilen); 251 sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); 252 } else 253 sg_init_one(asg, esph, sizeof(*esph)); 254 255 aead_givcrypt_set_callback(req, 0, esp_output_done, skb); 256 aead_givcrypt_set_crypt(req, sg, sg, clen, iv); 257 aead_givcrypt_set_assoc(req, asg, assoclen); 258 aead_givcrypt_set_giv(req, esph->enc_data, 259 XFRM_SKB_CB(skb)->seq.output.low + 260 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); 261 262 ESP_SKB_CB(skb)->tmp = tmp; 263 err = crypto_aead_givencrypt(req); 264 if (err == -EINPROGRESS) 265 goto error; 266 267 if (err == -EBUSY) 268 err = NET_XMIT_DROP; 269 270 kfree(tmp); 271 272 error: 273 return err; 274 } 275 276 static int esp_input_done2(struct sk_buff *skb, int err) 277 { 278 const struct iphdr *iph; 279 struct xfrm_state *x = xfrm_input_state(skb); 280 struct crypto_aead *aead = x->data; 281 int alen = crypto_aead_authsize(aead); 282 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 283 int elen = skb->len - hlen; 284 int ihl; 285 u8 nexthdr[2]; 286 int padlen; 287 288 kfree(ESP_SKB_CB(skb)->tmp); 289 290 if (unlikely(err)) 291 goto out; 292 293 if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) 294 BUG(); 295 296 err = -EINVAL; 297 padlen = nexthdr[0]; 298 if (padlen + 2 + alen >= elen) 299 goto out; 300 301 /* ... check padding bits here. Silly. :-) */ 302 303 iph = ip_hdr(skb); 304 ihl = iph->ihl * 4; 305 306 if (x->encap) { 307 struct xfrm_encap_tmpl *encap = x->encap; 308 struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); 309 310 /* 311 * 1) if the NAT-T peer's IP or port changed then 312 * advertize the change to the keying daemon. 313 * This is an inbound SA, so just compare 314 * SRC ports. 315 */ 316 if (iph->saddr != x->props.saddr.a4 || 317 uh->source != encap->encap_sport) { 318 xfrm_address_t ipaddr; 319 320 ipaddr.a4 = iph->saddr; 321 km_new_mapping(x, &ipaddr, uh->source); 322 323 /* XXX: perhaps add an extra 324 * policy check here, to see 325 * if we should allow or 326 * reject a packet from a 327 * different source 328 * address/port. 329 */ 330 } 331 332 /* 333 * 2) ignore UDP/TCP checksums in case 334 * of NAT-T in Transport Mode, or 335 * perform other post-processing fixes 336 * as per draft-ietf-ipsec-udp-encaps-06, 337 * section 3.1.2 338 */ 339 if (x->props.mode == XFRM_MODE_TRANSPORT) 340 skb->ip_summed = CHECKSUM_UNNECESSARY; 341 } 342 343 pskb_trim(skb, skb->len - alen - padlen - 2); 344 __skb_pull(skb, hlen); 345 if (x->props.mode == XFRM_MODE_TUNNEL) 346 skb_reset_transport_header(skb); 347 else 348 skb_set_transport_header(skb, -ihl); 349 350 err = nexthdr[1]; 351 352 /* RFC4303: Drop dummy packets without any error */ 353 if (err == IPPROTO_NONE) 354 err = -EINVAL; 355 356 out: 357 return err; 358 } 359 360 static void esp_input_done(struct crypto_async_request *base, int err) 361 { 362 struct sk_buff *skb = base->data; 363 364 xfrm_input_resume(skb, esp_input_done2(skb, err)); 365 } 366 367 /* 368 * Note: detecting truncated vs. non-truncated authentication data is very 369 * expensive, so we only support truncated data, which is the recommended 370 * and common case. 371 */ 372 static int esp_input(struct xfrm_state *x, struct sk_buff *skb) 373 { 374 struct ip_esp_hdr *esph; 375 struct crypto_aead *aead = x->data; 376 struct aead_request *req; 377 struct sk_buff *trailer; 378 int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead); 379 int nfrags; 380 int assoclen; 381 int sglists; 382 int seqhilen; 383 __be32 *seqhi; 384 void *tmp; 385 u8 *iv; 386 struct scatterlist *sg; 387 struct scatterlist *asg; 388 int err = -EINVAL; 389 390 if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) 391 goto out; 392 393 if (elen <= 0) 394 goto out; 395 396 err = skb_cow_data(skb, 0, &trailer); 397 if (err < 0) 398 goto out; 399 400 nfrags = err; 401 402 assoclen = sizeof(*esph); 403 sglists = 1; 404 seqhilen = 0; 405 406 if (x->props.flags & XFRM_STATE_ESN) { 407 sglists += 2; 408 seqhilen += sizeof(__be32); 409 assoclen += seqhilen; 410 } 411 412 err = -ENOMEM; 413 tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); 414 if (!tmp) 415 goto out; 416 417 ESP_SKB_CB(skb)->tmp = tmp; 418 seqhi = esp_tmp_seqhi(tmp); 419 iv = esp_tmp_iv(aead, tmp, seqhilen); 420 req = esp_tmp_req(aead, iv); 421 asg = esp_req_sg(aead, req); 422 sg = asg + sglists; 423 424 skb->ip_summed = CHECKSUM_NONE; 425 426 esph = (struct ip_esp_hdr *)skb->data; 427 428 /* Get ivec. This can be wrong, check against another impls. */ 429 iv = esph->enc_data; 430 431 sg_init_table(sg, nfrags); 432 skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen); 433 434 if ((x->props.flags & XFRM_STATE_ESN)) { 435 sg_init_table(asg, 3); 436 sg_set_buf(asg, &esph->spi, sizeof(__be32)); 437 *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; 438 sg_set_buf(asg + 1, seqhi, seqhilen); 439 sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); 440 } else 441 sg_init_one(asg, esph, sizeof(*esph)); 442 443 aead_request_set_callback(req, 0, esp_input_done, skb); 444 aead_request_set_crypt(req, sg, sg, elen, iv); 445 aead_request_set_assoc(req, asg, assoclen); 446 447 err = crypto_aead_decrypt(req); 448 if (err == -EINPROGRESS) 449 goto out; 450 451 err = esp_input_done2(skb, err); 452 453 out: 454 return err; 455 } 456 457 static u32 esp4_get_mtu(struct xfrm_state *x, int mtu) 458 { 459 struct crypto_aead *aead = x->data; 460 u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 461 unsigned int net_adj; 462 463 switch (x->props.mode) { 464 case XFRM_MODE_TRANSPORT: 465 case XFRM_MODE_BEET: 466 net_adj = sizeof(struct iphdr); 467 break; 468 case XFRM_MODE_TUNNEL: 469 net_adj = 0; 470 break; 471 default: 472 BUG(); 473 } 474 475 return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - 476 net_adj) & ~(blksize - 1)) + net_adj - 2; 477 } 478 479 static int esp4_err(struct sk_buff *skb, u32 info) 480 { 481 struct net *net = dev_net(skb->dev); 482 const struct iphdr *iph = (const struct iphdr *)skb->data; 483 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); 484 struct xfrm_state *x; 485 486 switch (icmp_hdr(skb)->type) { 487 case ICMP_DEST_UNREACH: 488 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) 489 return 0; 490 case ICMP_REDIRECT: 491 break; 492 default: 493 return 0; 494 } 495 496 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 497 esph->spi, IPPROTO_ESP, AF_INET); 498 if (!x) 499 return 0; 500 501 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) 502 ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0); 503 else 504 ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0); 505 xfrm_state_put(x); 506 507 return 0; 508 } 509 510 static void esp_destroy(struct xfrm_state *x) 511 { 512 struct crypto_aead *aead = x->data; 513 514 if (!aead) 515 return; 516 517 crypto_free_aead(aead); 518 } 519 520 static int esp_init_aead(struct xfrm_state *x) 521 { 522 struct crypto_aead *aead; 523 int err; 524 525 aead = crypto_alloc_aead(x->aead->alg_name, 0, 0); 526 err = PTR_ERR(aead); 527 if (IS_ERR(aead)) 528 goto error; 529 530 x->data = aead; 531 532 err = crypto_aead_setkey(aead, x->aead->alg_key, 533 (x->aead->alg_key_len + 7) / 8); 534 if (err) 535 goto error; 536 537 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); 538 if (err) 539 goto error; 540 541 error: 542 return err; 543 } 544 545 static int esp_init_authenc(struct xfrm_state *x) 546 { 547 struct crypto_aead *aead; 548 struct crypto_authenc_key_param *param; 549 struct rtattr *rta; 550 char *key; 551 char *p; 552 char authenc_name[CRYPTO_MAX_ALG_NAME]; 553 unsigned int keylen; 554 int err; 555 556 err = -EINVAL; 557 if (!x->ealg) 558 goto error; 559 560 err = -ENAMETOOLONG; 561 562 if ((x->props.flags & XFRM_STATE_ESN)) { 563 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 564 "authencesn(%s,%s)", 565 x->aalg ? x->aalg->alg_name : "digest_null", 566 x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) 567 goto error; 568 } else { 569 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 570 "authenc(%s,%s)", 571 x->aalg ? x->aalg->alg_name : "digest_null", 572 x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) 573 goto error; 574 } 575 576 aead = crypto_alloc_aead(authenc_name, 0, 0); 577 err = PTR_ERR(aead); 578 if (IS_ERR(aead)) 579 goto error; 580 581 x->data = aead; 582 583 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + 584 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); 585 err = -ENOMEM; 586 key = kmalloc(keylen, GFP_KERNEL); 587 if (!key) 588 goto error; 589 590 p = key; 591 rta = (void *)p; 592 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 593 rta->rta_len = RTA_LENGTH(sizeof(*param)); 594 param = RTA_DATA(rta); 595 p += RTA_SPACE(sizeof(*param)); 596 597 if (x->aalg) { 598 struct xfrm_algo_desc *aalg_desc; 599 600 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); 601 p += (x->aalg->alg_key_len + 7) / 8; 602 603 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 604 BUG_ON(!aalg_desc); 605 606 err = -EINVAL; 607 if (aalg_desc->uinfo.auth.icv_fullbits / 8 != 608 crypto_aead_authsize(aead)) { 609 pr_info("ESP: %s digestsize %u != %hu\n", 610 x->aalg->alg_name, 611 crypto_aead_authsize(aead), 612 aalg_desc->uinfo.auth.icv_fullbits / 8); 613 goto free_key; 614 } 615 616 err = crypto_aead_setauthsize( 617 aead, x->aalg->alg_trunc_len / 8); 618 if (err) 619 goto free_key; 620 } 621 622 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); 623 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); 624 625 err = crypto_aead_setkey(aead, key, keylen); 626 627 free_key: 628 kfree(key); 629 630 error: 631 return err; 632 } 633 634 static int esp_init_state(struct xfrm_state *x) 635 { 636 struct crypto_aead *aead; 637 u32 align; 638 int err; 639 640 x->data = NULL; 641 642 if (x->aead) 643 err = esp_init_aead(x); 644 else 645 err = esp_init_authenc(x); 646 647 if (err) 648 goto error; 649 650 aead = x->data; 651 652 x->props.header_len = sizeof(struct ip_esp_hdr) + 653 crypto_aead_ivsize(aead); 654 if (x->props.mode == XFRM_MODE_TUNNEL) 655 x->props.header_len += sizeof(struct iphdr); 656 else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6) 657 x->props.header_len += IPV4_BEET_PHMAXLEN; 658 if (x->encap) { 659 struct xfrm_encap_tmpl *encap = x->encap; 660 661 switch (encap->encap_type) { 662 default: 663 goto error; 664 case UDP_ENCAP_ESPINUDP: 665 x->props.header_len += sizeof(struct udphdr); 666 break; 667 case UDP_ENCAP_ESPINUDP_NON_IKE: 668 x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32); 669 break; 670 } 671 } 672 673 align = ALIGN(crypto_aead_blocksize(aead), 4); 674 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); 675 676 error: 677 return err; 678 } 679 680 static int esp4_rcv_cb(struct sk_buff *skb, int err) 681 { 682 return 0; 683 } 684 685 static const struct xfrm_type esp_type = 686 { 687 .description = "ESP4", 688 .owner = THIS_MODULE, 689 .proto = IPPROTO_ESP, 690 .flags = XFRM_TYPE_REPLAY_PROT, 691 .init_state = esp_init_state, 692 .destructor = esp_destroy, 693 .get_mtu = esp4_get_mtu, 694 .input = esp_input, 695 .output = esp_output 696 }; 697 698 static struct xfrm4_protocol esp4_protocol = { 699 .handler = xfrm4_rcv, 700 .input_handler = xfrm_input, 701 .cb_handler = esp4_rcv_cb, 702 .err_handler = esp4_err, 703 .priority = 0, 704 }; 705 706 static int __init esp4_init(void) 707 { 708 if (xfrm_register_type(&esp_type, AF_INET) < 0) { 709 pr_info("%s: can't add xfrm type\n", __func__); 710 return -EAGAIN; 711 } 712 if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) { 713 pr_info("%s: can't add protocol\n", __func__); 714 xfrm_unregister_type(&esp_type, AF_INET); 715 return -EAGAIN; 716 } 717 return 0; 718 } 719 720 static void __exit esp4_fini(void) 721 { 722 if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0) 723 pr_info("%s: can't remove protocol\n", __func__); 724 if (xfrm_unregister_type(&esp_type, AF_INET) < 0) 725 pr_info("%s: can't remove xfrm type\n", __func__); 726 } 727 728 module_init(esp4_init); 729 module_exit(esp4_fini); 730 MODULE_LICENSE("GPL"); 731 MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP); 732