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, see <http://www.gnu.org/licenses/>. 16 * 17 * Authors 18 * 19 * Mitsuru KANDA @USAGI : IPv6 Support 20 * Kazunori MIYAZAWA @USAGI : 21 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 22 * 23 * This file is derived from net/ipv4/esp.c 24 */ 25 26 #define pr_fmt(fmt) "IPv6: " fmt 27 28 #include <crypto/aead.h> 29 #include <crypto/authenc.h> 30 #include <linux/err.h> 31 #include <linux/module.h> 32 #include <net/ip.h> 33 #include <net/xfrm.h> 34 #include <net/esp.h> 35 #include <linux/scatterlist.h> 36 #include <linux/kernel.h> 37 #include <linux/pfkeyv2.h> 38 #include <linux/random.h> 39 #include <linux/slab.h> 40 #include <linux/spinlock.h> 41 #include <net/ip6_route.h> 42 #include <net/icmp.h> 43 #include <net/ipv6.h> 44 #include <net/protocol.h> 45 #include <linux/icmpv6.h> 46 47 #include <linux/highmem.h> 48 49 struct esp_skb_cb { 50 struct xfrm_skb_cb xfrm; 51 void *tmp; 52 }; 53 54 #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) 55 56 static u32 esp6_get_mtu(struct xfrm_state *x, int mtu); 57 58 /* 59 * Allocate an AEAD request structure with extra space for SG and IV. 60 * 61 * For alignment considerations the upper 32 bits of the sequence number are 62 * placed at the front, if present. Followed by the IV, the request and finally 63 * the SG list. 64 * 65 * TODO: Use spare space in skb for this where possible. 66 */ 67 static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqihlen) 68 { 69 unsigned int len; 70 71 len = seqihlen; 72 73 len += crypto_aead_ivsize(aead); 74 75 if (len) { 76 len += crypto_aead_alignmask(aead) & 77 ~(crypto_tfm_ctx_alignment() - 1); 78 len = ALIGN(len, crypto_tfm_ctx_alignment()); 79 } 80 81 len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); 82 len = ALIGN(len, __alignof__(struct scatterlist)); 83 84 len += sizeof(struct scatterlist) * nfrags; 85 86 return kmalloc(len, GFP_ATOMIC); 87 } 88 89 static inline __be32 *esp_tmp_seqhi(void *tmp) 90 { 91 return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); 92 } 93 94 static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) 95 { 96 return crypto_aead_ivsize(aead) ? 97 PTR_ALIGN((u8 *)tmp + seqhilen, 98 crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; 99 } 100 101 static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) 102 { 103 struct aead_request *req; 104 105 req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), 106 crypto_tfm_ctx_alignment()); 107 aead_request_set_tfm(req, aead); 108 return req; 109 } 110 111 static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, 112 struct aead_request *req) 113 { 114 return (void *)ALIGN((unsigned long)(req + 1) + 115 crypto_aead_reqsize(aead), 116 __alignof__(struct scatterlist)); 117 } 118 119 static void esp_ssg_unref(struct xfrm_state *x, void *tmp) 120 { 121 __be32 *seqhi; 122 struct crypto_aead *aead = x->data; 123 int seqhilen = 0; 124 u8 *iv; 125 struct aead_request *req; 126 struct scatterlist *sg; 127 128 if (x->props.flags & XFRM_STATE_ESN) 129 seqhilen += sizeof(__be32); 130 131 seqhi = esp_tmp_seqhi(tmp); 132 iv = esp_tmp_iv(aead, tmp, seqhilen); 133 req = esp_tmp_req(aead, iv); 134 135 /* Unref skb_frag_pages in the src scatterlist if necessary. 136 * Skip the first sg which comes from skb->data. 137 */ 138 if (req->src != req->dst) 139 for (sg = sg_next(req->src); sg; sg = sg_next(sg)) 140 put_page(sg_page(sg)); 141 } 142 143 static void esp_output_done(struct crypto_async_request *base, int err) 144 { 145 struct sk_buff *skb = base->data; 146 void *tmp; 147 struct dst_entry *dst = skb_dst(skb); 148 struct xfrm_state *x = dst->xfrm; 149 150 tmp = ESP_SKB_CB(skb)->tmp; 151 esp_ssg_unref(x, tmp); 152 kfree(tmp); 153 xfrm_output_resume(skb, err); 154 } 155 156 /* Move ESP header back into place. */ 157 static void esp_restore_header(struct sk_buff *skb, unsigned int offset) 158 { 159 struct ip_esp_hdr *esph = (void *)(skb->data + offset); 160 void *tmp = ESP_SKB_CB(skb)->tmp; 161 __be32 *seqhi = esp_tmp_seqhi(tmp); 162 163 esph->seq_no = esph->spi; 164 esph->spi = *seqhi; 165 } 166 167 static void esp_output_restore_header(struct sk_buff *skb) 168 { 169 esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); 170 } 171 172 static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb, 173 struct ip_esp_hdr *esph, 174 __be32 *seqhi) 175 { 176 struct xfrm_state *x = skb_dst(skb)->xfrm; 177 178 /* For ESN we move the header forward by 4 bytes to 179 * accomodate the high bits. We will move it back after 180 * encryption. 181 */ 182 if ((x->props.flags & XFRM_STATE_ESN)) { 183 esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); 184 *seqhi = esph->spi; 185 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); 186 } 187 188 esph->spi = x->id.spi; 189 190 return esph; 191 } 192 193 static void esp_output_done_esn(struct crypto_async_request *base, int err) 194 { 195 struct sk_buff *skb = base->data; 196 197 esp_output_restore_header(skb); 198 esp_output_done(base, err); 199 } 200 201 static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) 202 { 203 /* Fill padding... */ 204 if (tfclen) { 205 memset(tail, 0, tfclen); 206 tail += tfclen; 207 } 208 do { 209 int i; 210 for (i = 0; i < plen - 2; i++) 211 tail[i] = i + 1; 212 } while (0); 213 tail[plen - 2] = plen - 2; 214 tail[plen - 1] = proto; 215 } 216 217 static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) 218 { 219 int err; 220 struct ip_esp_hdr *esph; 221 struct crypto_aead *aead; 222 struct aead_request *req; 223 struct scatterlist *sg, *dsg; 224 struct sk_buff *trailer; 225 struct page *page; 226 void *tmp; 227 int blksize; 228 int clen; 229 int alen; 230 int plen; 231 int ivlen; 232 int tfclen; 233 int nfrags; 234 int assoclen; 235 int seqhilen; 236 int tailen; 237 u8 *iv; 238 u8 *tail; 239 u8 *vaddr; 240 __be32 *seqhi; 241 __be64 seqno; 242 __u8 proto = *skb_mac_header(skb); 243 244 /* skb is pure payload to encrypt */ 245 aead = x->data; 246 alen = crypto_aead_authsize(aead); 247 ivlen = crypto_aead_ivsize(aead); 248 249 tfclen = 0; 250 if (x->tfcpad) { 251 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); 252 u32 padto; 253 254 padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached)); 255 if (skb->len < padto) 256 tfclen = padto - skb->len; 257 } 258 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 259 clen = ALIGN(skb->len + 2 + tfclen, blksize); 260 plen = clen - skb->len - tfclen; 261 tailen = tfclen + plen + alen; 262 263 assoclen = sizeof(*esph); 264 seqhilen = 0; 265 266 if (x->props.flags & XFRM_STATE_ESN) { 267 seqhilen += sizeof(__be32); 268 assoclen += seqhilen; 269 } 270 271 *skb_mac_header(skb) = IPPROTO_ESP; 272 esph = ip_esp_hdr(skb); 273 274 if (!skb_cloned(skb)) { 275 if (tailen <= skb_availroom(skb)) { 276 nfrags = 1; 277 trailer = skb; 278 tail = skb_tail_pointer(trailer); 279 280 goto skip_cow; 281 } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) 282 && !skb_has_frag_list(skb)) { 283 int allocsize; 284 struct sock *sk = skb->sk; 285 struct page_frag *pfrag = &x->xfrag; 286 287 allocsize = ALIGN(tailen, L1_CACHE_BYTES); 288 289 spin_lock_bh(&x->lock); 290 291 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 292 spin_unlock_bh(&x->lock); 293 goto cow; 294 } 295 296 page = pfrag->page; 297 get_page(page); 298 299 vaddr = kmap_atomic(page); 300 301 tail = vaddr + pfrag->offset; 302 303 esp_output_fill_trailer(tail, tfclen, plen, proto); 304 305 kunmap_atomic(vaddr); 306 307 nfrags = skb_shinfo(skb)->nr_frags; 308 309 __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, 310 tailen); 311 skb_shinfo(skb)->nr_frags = ++nfrags; 312 313 pfrag->offset = pfrag->offset + allocsize; 314 nfrags++; 315 316 skb->len += tailen; 317 skb->data_len += tailen; 318 skb->truesize += tailen; 319 if (sk) 320 atomic_add(tailen, &sk->sk_wmem_alloc); 321 322 skb_push(skb, -skb_network_offset(skb)); 323 324 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 325 esph->spi = x->id.spi; 326 327 tmp = esp_alloc_tmp(aead, nfrags + 2, seqhilen); 328 if (!tmp) { 329 spin_unlock_bh(&x->lock); 330 err = -ENOMEM; 331 goto error; 332 } 333 seqhi = esp_tmp_seqhi(tmp); 334 iv = esp_tmp_iv(aead, tmp, seqhilen); 335 req = esp_tmp_req(aead, iv); 336 sg = esp_req_sg(aead, req); 337 dsg = &sg[nfrags]; 338 339 esph = esp_output_set_esn(skb, esph, seqhi); 340 341 sg_init_table(sg, nfrags); 342 skb_to_sgvec(skb, sg, 343 (unsigned char *)esph - skb->data, 344 assoclen + ivlen + clen + alen); 345 346 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); 347 348 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 349 spin_unlock_bh(&x->lock); 350 err = -ENOMEM; 351 goto error; 352 } 353 354 skb_shinfo(skb)->nr_frags = 1; 355 356 page = pfrag->page; 357 get_page(page); 358 /* replace page frags in skb with new page */ 359 __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); 360 pfrag->offset = pfrag->offset + allocsize; 361 362 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); 363 skb_to_sgvec(skb, dsg, 364 (unsigned char *)esph - skb->data, 365 assoclen + ivlen + clen + alen); 366 367 spin_unlock_bh(&x->lock); 368 369 goto skip_cow2; 370 } 371 } 372 373 cow: 374 err = skb_cow_data(skb, tailen, &trailer); 375 if (err < 0) 376 goto error; 377 nfrags = err; 378 379 tail = skb_tail_pointer(trailer); 380 esph = ip_esp_hdr(skb); 381 382 skip_cow: 383 esp_output_fill_trailer(tail, tfclen, plen, proto); 384 385 pskb_put(skb, trailer, clen - skb->len + alen); 386 skb_push(skb, -skb_network_offset(skb)); 387 388 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 389 esph->spi = x->id.spi; 390 391 tmp = esp_alloc_tmp(aead, nfrags, seqhilen); 392 if (!tmp) { 393 err = -ENOMEM; 394 goto error; 395 } 396 397 seqhi = esp_tmp_seqhi(tmp); 398 iv = esp_tmp_iv(aead, tmp, seqhilen); 399 req = esp_tmp_req(aead, iv); 400 sg = esp_req_sg(aead, req); 401 dsg = sg; 402 403 esph = esp_output_set_esn(skb, esph, seqhi); 404 405 sg_init_table(sg, nfrags); 406 skb_to_sgvec(skb, sg, 407 (unsigned char *)esph - skb->data, 408 assoclen + ivlen + clen + alen); 409 410 skip_cow2: 411 if ((x->props.flags & XFRM_STATE_ESN)) 412 aead_request_set_callback(req, 0, esp_output_done_esn, skb); 413 else 414 aead_request_set_callback(req, 0, esp_output_done, skb); 415 416 aead_request_set_crypt(req, sg, dsg, ivlen + clen, iv); 417 aead_request_set_ad(req, assoclen); 418 419 seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + 420 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); 421 422 memset(iv, 0, ivlen); 423 memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&seqno + 8 - min(ivlen, 8), 424 min(ivlen, 8)); 425 426 ESP_SKB_CB(skb)->tmp = tmp; 427 err = crypto_aead_encrypt(req); 428 429 switch (err) { 430 case -EINPROGRESS: 431 goto error; 432 433 case -EBUSY: 434 err = NET_XMIT_DROP; 435 break; 436 437 case 0: 438 if ((x->props.flags & XFRM_STATE_ESN)) 439 esp_output_restore_header(skb); 440 } 441 442 if (sg != dsg) 443 esp_ssg_unref(x, tmp); 444 kfree(tmp); 445 446 error: 447 return err; 448 } 449 450 static int esp_input_done2(struct sk_buff *skb, int err) 451 { 452 struct xfrm_state *x = xfrm_input_state(skb); 453 struct crypto_aead *aead = x->data; 454 int alen = crypto_aead_authsize(aead); 455 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 456 int elen = skb->len - hlen; 457 int hdr_len = skb_network_header_len(skb); 458 int padlen; 459 u8 nexthdr[2]; 460 461 kfree(ESP_SKB_CB(skb)->tmp); 462 463 if (unlikely(err)) 464 goto out; 465 466 if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2)) 467 BUG(); 468 469 err = -EINVAL; 470 padlen = nexthdr[0]; 471 if (padlen + 2 + alen >= elen) { 472 net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", 473 padlen + 2, elen - alen); 474 goto out; 475 } 476 477 /* ... check padding bits here. Silly. :-) */ 478 479 pskb_trim(skb, skb->len - alen - padlen - 2); 480 __skb_pull(skb, hlen); 481 if (x->props.mode == XFRM_MODE_TUNNEL) 482 skb_reset_transport_header(skb); 483 else 484 skb_set_transport_header(skb, -hdr_len); 485 486 err = nexthdr[1]; 487 488 /* RFC4303: Drop dummy packets without any error */ 489 if (err == IPPROTO_NONE) 490 err = -EINVAL; 491 492 out: 493 return err; 494 } 495 496 static void esp_input_done(struct crypto_async_request *base, int err) 497 { 498 struct sk_buff *skb = base->data; 499 500 xfrm_input_resume(skb, esp_input_done2(skb, err)); 501 } 502 503 static void esp_input_restore_header(struct sk_buff *skb) 504 { 505 esp_restore_header(skb, 0); 506 __skb_pull(skb, 4); 507 } 508 509 static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) 510 { 511 struct xfrm_state *x = xfrm_input_state(skb); 512 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)skb->data; 513 514 /* For ESN we move the header forward by 4 bytes to 515 * accomodate the high bits. We will move it back after 516 * decryption. 517 */ 518 if ((x->props.flags & XFRM_STATE_ESN)) { 519 esph = (void *)skb_push(skb, 4); 520 *seqhi = esph->spi; 521 esph->spi = esph->seq_no; 522 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; 523 } 524 } 525 526 static void esp_input_done_esn(struct crypto_async_request *base, int err) 527 { 528 struct sk_buff *skb = base->data; 529 530 esp_input_restore_header(skb); 531 esp_input_done(base, err); 532 } 533 534 static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) 535 { 536 struct ip_esp_hdr *esph; 537 struct crypto_aead *aead = x->data; 538 struct aead_request *req; 539 struct sk_buff *trailer; 540 int ivlen = crypto_aead_ivsize(aead); 541 int elen = skb->len - sizeof(*esph) - ivlen; 542 int nfrags; 543 int assoclen; 544 int seqhilen; 545 int ret = 0; 546 void *tmp; 547 __be32 *seqhi; 548 u8 *iv; 549 struct scatterlist *sg; 550 551 if (!pskb_may_pull(skb, sizeof(*esph) + ivlen)) { 552 ret = -EINVAL; 553 goto out; 554 } 555 556 if (elen <= 0) { 557 ret = -EINVAL; 558 goto out; 559 } 560 561 assoclen = sizeof(*esph); 562 seqhilen = 0; 563 564 if (x->props.flags & XFRM_STATE_ESN) { 565 seqhilen += sizeof(__be32); 566 assoclen += seqhilen; 567 } 568 569 if (!skb_cloned(skb)) { 570 if (!skb_is_nonlinear(skb)) { 571 nfrags = 1; 572 573 goto skip_cow; 574 } else if (!skb_has_frag_list(skb)) { 575 nfrags = skb_shinfo(skb)->nr_frags; 576 nfrags++; 577 578 goto skip_cow; 579 } 580 } 581 582 nfrags = skb_cow_data(skb, 0, &trailer); 583 if (nfrags < 0) { 584 ret = -EINVAL; 585 goto out; 586 } 587 588 skip_cow: 589 ret = -ENOMEM; 590 tmp = esp_alloc_tmp(aead, nfrags, seqhilen); 591 if (!tmp) 592 goto out; 593 594 ESP_SKB_CB(skb)->tmp = tmp; 595 seqhi = esp_tmp_seqhi(tmp); 596 iv = esp_tmp_iv(aead, tmp, seqhilen); 597 req = esp_tmp_req(aead, iv); 598 sg = esp_req_sg(aead, req); 599 600 esp_input_set_header(skb, seqhi); 601 602 sg_init_table(sg, nfrags); 603 skb_to_sgvec(skb, sg, 0, skb->len); 604 605 skb->ip_summed = CHECKSUM_NONE; 606 607 if ((x->props.flags & XFRM_STATE_ESN)) 608 aead_request_set_callback(req, 0, esp_input_done_esn, skb); 609 else 610 aead_request_set_callback(req, 0, esp_input_done, skb); 611 612 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); 613 aead_request_set_ad(req, assoclen); 614 615 ret = crypto_aead_decrypt(req); 616 if (ret == -EINPROGRESS) 617 goto out; 618 619 if ((x->props.flags & XFRM_STATE_ESN)) 620 esp_input_restore_header(skb); 621 622 ret = esp_input_done2(skb, ret); 623 624 out: 625 return ret; 626 } 627 628 static u32 esp6_get_mtu(struct xfrm_state *x, int mtu) 629 { 630 struct crypto_aead *aead = x->data; 631 u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 632 unsigned int net_adj; 633 634 if (x->props.mode != XFRM_MODE_TUNNEL) 635 net_adj = sizeof(struct ipv6hdr); 636 else 637 net_adj = 0; 638 639 return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - 640 net_adj) & ~(blksize - 1)) + net_adj - 2; 641 } 642 643 static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 644 u8 type, u8 code, int offset, __be32 info) 645 { 646 struct net *net = dev_net(skb->dev); 647 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 648 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); 649 struct xfrm_state *x; 650 651 if (type != ICMPV6_PKT_TOOBIG && 652 type != NDISC_REDIRECT) 653 return 0; 654 655 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 656 esph->spi, IPPROTO_ESP, AF_INET6); 657 if (!x) 658 return 0; 659 660 if (type == NDISC_REDIRECT) 661 ip6_redirect(skb, net, skb->dev->ifindex, 0, 662 sock_net_uid(net, NULL)); 663 else 664 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 665 xfrm_state_put(x); 666 667 return 0; 668 } 669 670 static void esp6_destroy(struct xfrm_state *x) 671 { 672 struct crypto_aead *aead = x->data; 673 674 if (!aead) 675 return; 676 677 crypto_free_aead(aead); 678 } 679 680 static int esp_init_aead(struct xfrm_state *x) 681 { 682 char aead_name[CRYPTO_MAX_ALG_NAME]; 683 struct crypto_aead *aead; 684 int err; 685 686 err = -ENAMETOOLONG; 687 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", 688 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) 689 goto error; 690 691 aead = crypto_alloc_aead(aead_name, 0, 0); 692 err = PTR_ERR(aead); 693 if (IS_ERR(aead)) 694 goto error; 695 696 x->data = aead; 697 698 err = crypto_aead_setkey(aead, x->aead->alg_key, 699 (x->aead->alg_key_len + 7) / 8); 700 if (err) 701 goto error; 702 703 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); 704 if (err) 705 goto error; 706 707 error: 708 return err; 709 } 710 711 static int esp_init_authenc(struct xfrm_state *x) 712 { 713 struct crypto_aead *aead; 714 struct crypto_authenc_key_param *param; 715 struct rtattr *rta; 716 char *key; 717 char *p; 718 char authenc_name[CRYPTO_MAX_ALG_NAME]; 719 unsigned int keylen; 720 int err; 721 722 err = -EINVAL; 723 if (!x->ealg) 724 goto error; 725 726 err = -ENAMETOOLONG; 727 728 if ((x->props.flags & XFRM_STATE_ESN)) { 729 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 730 "%s%sauthencesn(%s,%s)%s", 731 x->geniv ?: "", x->geniv ? "(" : "", 732 x->aalg ? x->aalg->alg_name : "digest_null", 733 x->ealg->alg_name, 734 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) 735 goto error; 736 } else { 737 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 738 "%s%sauthenc(%s,%s)%s", 739 x->geniv ?: "", x->geniv ? "(" : "", 740 x->aalg ? x->aalg->alg_name : "digest_null", 741 x->ealg->alg_name, 742 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) 743 goto error; 744 } 745 746 aead = crypto_alloc_aead(authenc_name, 0, 0); 747 err = PTR_ERR(aead); 748 if (IS_ERR(aead)) 749 goto error; 750 751 x->data = aead; 752 753 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + 754 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); 755 err = -ENOMEM; 756 key = kmalloc(keylen, GFP_KERNEL); 757 if (!key) 758 goto error; 759 760 p = key; 761 rta = (void *)p; 762 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 763 rta->rta_len = RTA_LENGTH(sizeof(*param)); 764 param = RTA_DATA(rta); 765 p += RTA_SPACE(sizeof(*param)); 766 767 if (x->aalg) { 768 struct xfrm_algo_desc *aalg_desc; 769 770 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); 771 p += (x->aalg->alg_key_len + 7) / 8; 772 773 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 774 BUG_ON(!aalg_desc); 775 776 err = -EINVAL; 777 if (aalg_desc->uinfo.auth.icv_fullbits / 8 != 778 crypto_aead_authsize(aead)) { 779 pr_info("ESP: %s digestsize %u != %hu\n", 780 x->aalg->alg_name, 781 crypto_aead_authsize(aead), 782 aalg_desc->uinfo.auth.icv_fullbits / 8); 783 goto free_key; 784 } 785 786 err = crypto_aead_setauthsize( 787 aead, x->aalg->alg_trunc_len / 8); 788 if (err) 789 goto free_key; 790 } 791 792 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); 793 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); 794 795 err = crypto_aead_setkey(aead, key, keylen); 796 797 free_key: 798 kfree(key); 799 800 error: 801 return err; 802 } 803 804 static int esp6_init_state(struct xfrm_state *x) 805 { 806 struct crypto_aead *aead; 807 u32 align; 808 int err; 809 810 if (x->encap) 811 return -EINVAL; 812 813 x->data = NULL; 814 815 if (x->aead) 816 err = esp_init_aead(x); 817 else 818 err = esp_init_authenc(x); 819 820 if (err) 821 goto error; 822 823 aead = x->data; 824 825 x->props.header_len = sizeof(struct ip_esp_hdr) + 826 crypto_aead_ivsize(aead); 827 switch (x->props.mode) { 828 case XFRM_MODE_BEET: 829 if (x->sel.family != AF_INET6) 830 x->props.header_len += IPV4_BEET_PHMAXLEN + 831 (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); 832 break; 833 case XFRM_MODE_TRANSPORT: 834 break; 835 case XFRM_MODE_TUNNEL: 836 x->props.header_len += sizeof(struct ipv6hdr); 837 break; 838 default: 839 goto error; 840 } 841 842 align = ALIGN(crypto_aead_blocksize(aead), 4); 843 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); 844 845 error: 846 return err; 847 } 848 849 static int esp6_rcv_cb(struct sk_buff *skb, int err) 850 { 851 return 0; 852 } 853 854 static const struct xfrm_type esp6_type = { 855 .description = "ESP6", 856 .owner = THIS_MODULE, 857 .proto = IPPROTO_ESP, 858 .flags = XFRM_TYPE_REPLAY_PROT, 859 .init_state = esp6_init_state, 860 .destructor = esp6_destroy, 861 .get_mtu = esp6_get_mtu, 862 .input = esp6_input, 863 .output = esp6_output, 864 .hdr_offset = xfrm6_find_1stfragopt, 865 }; 866 867 static struct xfrm6_protocol esp6_protocol = { 868 .handler = xfrm6_rcv, 869 .cb_handler = esp6_rcv_cb, 870 .err_handler = esp6_err, 871 .priority = 0, 872 }; 873 874 static int __init esp6_init(void) 875 { 876 if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { 877 pr_info("%s: can't add xfrm type\n", __func__); 878 return -EAGAIN; 879 } 880 if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { 881 pr_info("%s: can't add protocol\n", __func__); 882 xfrm_unregister_type(&esp6_type, AF_INET6); 883 return -EAGAIN; 884 } 885 886 return 0; 887 } 888 889 static void __exit esp6_fini(void) 890 { 891 if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) 892 pr_info("%s: can't remove protocol\n", __func__); 893 if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0) 894 pr_info("%s: can't remove xfrm type\n", __func__); 895 } 896 897 module_init(esp6_init); 898 module_exit(esp6_fini); 899 900 MODULE_LICENSE("GPL"); 901 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP); 902