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); 260 261 ESP_SKB_CB(skb)->tmp = tmp; 262 err = crypto_aead_givencrypt(req); 263 if (err == -EINPROGRESS) 264 goto error; 265 266 if (err == -EBUSY) 267 err = NET_XMIT_DROP; 268 269 kfree(tmp); 270 271 error: 272 return err; 273 } 274 275 static int esp_input_done2(struct sk_buff *skb, int err) 276 { 277 const struct iphdr *iph; 278 struct xfrm_state *x = xfrm_input_state(skb); 279 struct crypto_aead *aead = x->data; 280 int alen = crypto_aead_authsize(aead); 281 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 282 int elen = skb->len - hlen; 283 int ihl; 284 u8 nexthdr[2]; 285 int padlen; 286 287 kfree(ESP_SKB_CB(skb)->tmp); 288 289 if (unlikely(err)) 290 goto out; 291 292 if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) 293 BUG(); 294 295 err = -EINVAL; 296 padlen = nexthdr[0]; 297 if (padlen + 2 + alen >= elen) 298 goto out; 299 300 /* ... check padding bits here. Silly. :-) */ 301 302 iph = ip_hdr(skb); 303 ihl = iph->ihl * 4; 304 305 if (x->encap) { 306 struct xfrm_encap_tmpl *encap = x->encap; 307 struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); 308 309 /* 310 * 1) if the NAT-T peer's IP or port changed then 311 * advertize the change to the keying daemon. 312 * This is an inbound SA, so just compare 313 * SRC ports. 314 */ 315 if (iph->saddr != x->props.saddr.a4 || 316 uh->source != encap->encap_sport) { 317 xfrm_address_t ipaddr; 318 319 ipaddr.a4 = iph->saddr; 320 km_new_mapping(x, &ipaddr, uh->source); 321 322 /* XXX: perhaps add an extra 323 * policy check here, to see 324 * if we should allow or 325 * reject a packet from a 326 * different source 327 * address/port. 328 */ 329 } 330 331 /* 332 * 2) ignore UDP/TCP checksums in case 333 * of NAT-T in Transport Mode, or 334 * perform other post-processing fixes 335 * as per draft-ietf-ipsec-udp-encaps-06, 336 * section 3.1.2 337 */ 338 if (x->props.mode == XFRM_MODE_TRANSPORT) 339 skb->ip_summed = CHECKSUM_UNNECESSARY; 340 } 341 342 pskb_trim(skb, skb->len - alen - padlen - 2); 343 __skb_pull(skb, hlen); 344 if (x->props.mode == XFRM_MODE_TUNNEL) 345 skb_reset_transport_header(skb); 346 else 347 skb_set_transport_header(skb, -ihl); 348 349 err = nexthdr[1]; 350 351 /* RFC4303: Drop dummy packets without any error */ 352 if (err == IPPROTO_NONE) 353 err = -EINVAL; 354 355 out: 356 return err; 357 } 358 359 static void esp_input_done(struct crypto_async_request *base, int err) 360 { 361 struct sk_buff *skb = base->data; 362 363 xfrm_input_resume(skb, esp_input_done2(skb, err)); 364 } 365 366 /* 367 * Note: detecting truncated vs. non-truncated authentication data is very 368 * expensive, so we only support truncated data, which is the recommended 369 * and common case. 370 */ 371 static int esp_input(struct xfrm_state *x, struct sk_buff *skb) 372 { 373 struct ip_esp_hdr *esph; 374 struct crypto_aead *aead = x->data; 375 struct aead_request *req; 376 struct sk_buff *trailer; 377 int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead); 378 int nfrags; 379 int assoclen; 380 int sglists; 381 int seqhilen; 382 __be32 *seqhi; 383 void *tmp; 384 u8 *iv; 385 struct scatterlist *sg; 386 struct scatterlist *asg; 387 int err = -EINVAL; 388 389 if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) 390 goto out; 391 392 if (elen <= 0) 393 goto out; 394 395 err = skb_cow_data(skb, 0, &trailer); 396 if (err < 0) 397 goto out; 398 399 nfrags = err; 400 401 assoclen = sizeof(*esph); 402 sglists = 1; 403 seqhilen = 0; 404 405 if (x->props.flags & XFRM_STATE_ESN) { 406 sglists += 2; 407 seqhilen += sizeof(__be32); 408 assoclen += seqhilen; 409 } 410 411 err = -ENOMEM; 412 tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); 413 if (!tmp) 414 goto out; 415 416 ESP_SKB_CB(skb)->tmp = tmp; 417 seqhi = esp_tmp_seqhi(tmp); 418 iv = esp_tmp_iv(aead, tmp, seqhilen); 419 req = esp_tmp_req(aead, iv); 420 asg = esp_req_sg(aead, req); 421 sg = asg + sglists; 422 423 skb->ip_summed = CHECKSUM_NONE; 424 425 esph = (struct ip_esp_hdr *)skb->data; 426 427 /* Get ivec. This can be wrong, check against another impls. */ 428 iv = esph->enc_data; 429 430 sg_init_table(sg, nfrags); 431 skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen); 432 433 if ((x->props.flags & XFRM_STATE_ESN)) { 434 sg_init_table(asg, 3); 435 sg_set_buf(asg, &esph->spi, sizeof(__be32)); 436 *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; 437 sg_set_buf(asg + 1, seqhi, seqhilen); 438 sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); 439 } else 440 sg_init_one(asg, esph, sizeof(*esph)); 441 442 aead_request_set_callback(req, 0, esp_input_done, skb); 443 aead_request_set_crypt(req, sg, sg, elen, iv); 444 aead_request_set_assoc(req, asg, assoclen); 445 446 err = crypto_aead_decrypt(req); 447 if (err == -EINPROGRESS) 448 goto out; 449 450 err = esp_input_done2(skb, err); 451 452 out: 453 return err; 454 } 455 456 static u32 esp4_get_mtu(struct xfrm_state *x, int mtu) 457 { 458 struct crypto_aead *aead = x->data; 459 u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 460 unsigned int net_adj; 461 462 switch (x->props.mode) { 463 case XFRM_MODE_TRANSPORT: 464 case XFRM_MODE_BEET: 465 net_adj = sizeof(struct iphdr); 466 break; 467 case XFRM_MODE_TUNNEL: 468 net_adj = 0; 469 break; 470 default: 471 BUG(); 472 } 473 474 return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - 475 net_adj) & ~(blksize - 1)) + net_adj - 2; 476 } 477 478 static int esp4_err(struct sk_buff *skb, u32 info) 479 { 480 struct net *net = dev_net(skb->dev); 481 const struct iphdr *iph = (const struct iphdr *)skb->data; 482 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); 483 struct xfrm_state *x; 484 485 switch (icmp_hdr(skb)->type) { 486 case ICMP_DEST_UNREACH: 487 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) 488 return 0; 489 case ICMP_REDIRECT: 490 break; 491 default: 492 return 0; 493 } 494 495 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 496 esph->spi, IPPROTO_ESP, AF_INET); 497 if (!x) 498 return 0; 499 500 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) 501 ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0); 502 else 503 ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0); 504 xfrm_state_put(x); 505 506 return 0; 507 } 508 509 static void esp_destroy(struct xfrm_state *x) 510 { 511 struct crypto_aead *aead = x->data; 512 513 if (!aead) 514 return; 515 516 crypto_free_aead(aead); 517 } 518 519 static int esp_init_aead(struct xfrm_state *x) 520 { 521 struct crypto_aead *aead; 522 int err; 523 524 aead = crypto_alloc_aead(x->aead->alg_name, 0, 0); 525 err = PTR_ERR(aead); 526 if (IS_ERR(aead)) 527 goto error; 528 529 x->data = aead; 530 531 err = crypto_aead_setkey(aead, x->aead->alg_key, 532 (x->aead->alg_key_len + 7) / 8); 533 if (err) 534 goto error; 535 536 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); 537 if (err) 538 goto error; 539 540 error: 541 return err; 542 } 543 544 static int esp_init_authenc(struct xfrm_state *x) 545 { 546 struct crypto_aead *aead; 547 struct crypto_authenc_key_param *param; 548 struct rtattr *rta; 549 char *key; 550 char *p; 551 char authenc_name[CRYPTO_MAX_ALG_NAME]; 552 unsigned int keylen; 553 int err; 554 555 err = -EINVAL; 556 if (x->ealg == NULL) 557 goto error; 558 559 err = -ENAMETOOLONG; 560 561 if ((x->props.flags & XFRM_STATE_ESN)) { 562 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 563 "authencesn(%s,%s)", 564 x->aalg ? x->aalg->alg_name : "digest_null", 565 x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) 566 goto error; 567 } else { 568 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 569 "authenc(%s,%s)", 570 x->aalg ? x->aalg->alg_name : "digest_null", 571 x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) 572 goto error; 573 } 574 575 aead = crypto_alloc_aead(authenc_name, 0, 0); 576 err = PTR_ERR(aead); 577 if (IS_ERR(aead)) 578 goto error; 579 580 x->data = aead; 581 582 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + 583 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); 584 err = -ENOMEM; 585 key = kmalloc(keylen, GFP_KERNEL); 586 if (!key) 587 goto error; 588 589 p = key; 590 rta = (void *)p; 591 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 592 rta->rta_len = RTA_LENGTH(sizeof(*param)); 593 param = RTA_DATA(rta); 594 p += RTA_SPACE(sizeof(*param)); 595 596 if (x->aalg) { 597 struct xfrm_algo_desc *aalg_desc; 598 599 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); 600 p += (x->aalg->alg_key_len + 7) / 8; 601 602 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 603 BUG_ON(!aalg_desc); 604 605 err = -EINVAL; 606 if (aalg_desc->uinfo.auth.icv_fullbits / 8 != 607 crypto_aead_authsize(aead)) { 608 pr_info("ESP: %s digestsize %u != %hu\n", 609 x->aalg->alg_name, 610 crypto_aead_authsize(aead), 611 aalg_desc->uinfo.auth.icv_fullbits / 8); 612 goto free_key; 613 } 614 615 err = crypto_aead_setauthsize( 616 aead, x->aalg->alg_trunc_len / 8); 617 if (err) 618 goto free_key; 619 } 620 621 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); 622 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); 623 624 err = crypto_aead_setkey(aead, key, keylen); 625 626 free_key: 627 kfree(key); 628 629 error: 630 return err; 631 } 632 633 static int esp_init_state(struct xfrm_state *x) 634 { 635 struct crypto_aead *aead; 636 u32 align; 637 int err; 638 639 x->data = NULL; 640 641 if (x->aead) 642 err = esp_init_aead(x); 643 else 644 err = esp_init_authenc(x); 645 646 if (err) 647 goto error; 648 649 aead = x->data; 650 651 x->props.header_len = sizeof(struct ip_esp_hdr) + 652 crypto_aead_ivsize(aead); 653 if (x->props.mode == XFRM_MODE_TUNNEL) 654 x->props.header_len += sizeof(struct iphdr); 655 else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6) 656 x->props.header_len += IPV4_BEET_PHMAXLEN; 657 if (x->encap) { 658 struct xfrm_encap_tmpl *encap = x->encap; 659 660 switch (encap->encap_type) { 661 default: 662 goto error; 663 case UDP_ENCAP_ESPINUDP: 664 x->props.header_len += sizeof(struct udphdr); 665 break; 666 case UDP_ENCAP_ESPINUDP_NON_IKE: 667 x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32); 668 break; 669 } 670 } 671 672 align = ALIGN(crypto_aead_blocksize(aead), 4); 673 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); 674 675 error: 676 return err; 677 } 678 679 static int esp4_rcv_cb(struct sk_buff *skb, int err) 680 { 681 return 0; 682 } 683 684 static const struct xfrm_type esp_type = 685 { 686 .description = "ESP4", 687 .owner = THIS_MODULE, 688 .proto = IPPROTO_ESP, 689 .flags = XFRM_TYPE_REPLAY_PROT, 690 .init_state = esp_init_state, 691 .destructor = esp_destroy, 692 .get_mtu = esp4_get_mtu, 693 .input = esp_input, 694 .output = esp_output 695 }; 696 697 static struct xfrm4_protocol esp4_protocol = { 698 .handler = xfrm4_rcv, 699 .input_handler = xfrm_input, 700 .cb_handler = esp4_rcv_cb, 701 .err_handler = esp4_err, 702 .priority = 0, 703 }; 704 705 static int __init esp4_init(void) 706 { 707 if (xfrm_register_type(&esp_type, AF_INET) < 0) { 708 pr_info("%s: can't add xfrm type\n", __func__); 709 return -EAGAIN; 710 } 711 if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) { 712 pr_info("%s: can't add protocol\n", __func__); 713 xfrm_unregister_type(&esp_type, AF_INET); 714 return -EAGAIN; 715 } 716 return 0; 717 } 718 719 static void __exit esp4_fini(void) 720 { 721 if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0) 722 pr_info("%s: can't remove protocol\n", __func__); 723 if (xfrm_unregister_type(&esp_type, AF_INET) < 0) 724 pr_info("%s: can't remove xfrm type\n", __func__); 725 } 726 727 module_init(esp4_init); 728 module_exit(esp4_fini); 729 MODULE_LICENSE("GPL"); 730 MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP); 731