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 xfrm_state *x, 174 struct ip_esp_hdr *esph, 175 __be32 *seqhi) 176 { 177 /* For ESN we move the header forward by 4 bytes to 178 * accomodate the high bits. We will move it back after 179 * encryption. 180 */ 181 if ((x->props.flags & XFRM_STATE_ESN)) { 182 struct xfrm_offload *xo = xfrm_offload(skb); 183 184 esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); 185 *seqhi = esph->spi; 186 if (xo) 187 esph->seq_no = htonl(xo->seq.hi); 188 else 189 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); 190 } 191 192 esph->spi = x->id.spi; 193 194 return esph; 195 } 196 197 static void esp_output_done_esn(struct crypto_async_request *base, int err) 198 { 199 struct sk_buff *skb = base->data; 200 201 esp_output_restore_header(skb); 202 esp_output_done(base, err); 203 } 204 205 static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) 206 { 207 /* Fill padding... */ 208 if (tfclen) { 209 memset(tail, 0, tfclen); 210 tail += tfclen; 211 } 212 do { 213 int i; 214 for (i = 0; i < plen - 2; i++) 215 tail[i] = i + 1; 216 } while (0); 217 tail[plen - 2] = plen - 2; 218 tail[plen - 1] = proto; 219 } 220 221 int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) 222 { 223 u8 *tail; 224 u8 *vaddr; 225 int nfrags; 226 struct page *page; 227 struct ip_esp_hdr *esph; 228 struct sk_buff *trailer; 229 int tailen = esp->tailen; 230 231 esph = ip_esp_hdr(skb); 232 233 if (!skb_cloned(skb)) { 234 if (tailen <= skb_availroom(skb)) { 235 nfrags = 1; 236 trailer = skb; 237 tail = skb_tail_pointer(trailer); 238 239 goto skip_cow; 240 } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) 241 && !skb_has_frag_list(skb)) { 242 int allocsize; 243 struct sock *sk = skb->sk; 244 struct page_frag *pfrag = &x->xfrag; 245 246 esp->inplace = false; 247 248 allocsize = ALIGN(tailen, L1_CACHE_BYTES); 249 250 spin_lock_bh(&x->lock); 251 252 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 253 spin_unlock_bh(&x->lock); 254 goto cow; 255 } 256 257 page = pfrag->page; 258 get_page(page); 259 260 vaddr = kmap_atomic(page); 261 262 tail = vaddr + pfrag->offset; 263 264 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); 265 266 kunmap_atomic(vaddr); 267 268 spin_unlock_bh(&x->lock); 269 270 nfrags = skb_shinfo(skb)->nr_frags; 271 272 __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, 273 tailen); 274 skb_shinfo(skb)->nr_frags = ++nfrags; 275 276 pfrag->offset = pfrag->offset + allocsize; 277 nfrags++; 278 279 skb->len += tailen; 280 skb->data_len += tailen; 281 skb->truesize += tailen; 282 if (sk) 283 atomic_add(tailen, &sk->sk_wmem_alloc); 284 285 goto out; 286 } 287 } 288 289 cow: 290 nfrags = skb_cow_data(skb, tailen, &trailer); 291 if (nfrags < 0) 292 goto out; 293 tail = skb_tail_pointer(trailer); 294 295 skip_cow: 296 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); 297 pskb_put(skb, trailer, tailen); 298 299 out: 300 return nfrags; 301 } 302 EXPORT_SYMBOL_GPL(esp6_output_head); 303 304 int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) 305 { 306 u8 *iv; 307 int alen; 308 void *tmp; 309 int ivlen; 310 int assoclen; 311 int seqhilen; 312 __be32 *seqhi; 313 struct page *page; 314 struct ip_esp_hdr *esph; 315 struct aead_request *req; 316 struct crypto_aead *aead; 317 struct scatterlist *sg, *dsg; 318 int err = -ENOMEM; 319 320 assoclen = sizeof(struct ip_esp_hdr); 321 seqhilen = 0; 322 323 if (x->props.flags & XFRM_STATE_ESN) { 324 seqhilen += sizeof(__be32); 325 assoclen += sizeof(__be32); 326 } 327 328 aead = x->data; 329 alen = crypto_aead_authsize(aead); 330 ivlen = crypto_aead_ivsize(aead); 331 332 tmp = esp_alloc_tmp(aead, esp->nfrags + 2, seqhilen); 333 if (!tmp) 334 goto error; 335 336 seqhi = esp_tmp_seqhi(tmp); 337 iv = esp_tmp_iv(aead, tmp, seqhilen); 338 req = esp_tmp_req(aead, iv); 339 sg = esp_req_sg(aead, req); 340 341 if (esp->inplace) 342 dsg = sg; 343 else 344 dsg = &sg[esp->nfrags]; 345 346 esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi); 347 348 sg_init_table(sg, esp->nfrags); 349 skb_to_sgvec(skb, sg, 350 (unsigned char *)esph - skb->data, 351 assoclen + ivlen + esp->clen + alen); 352 353 if (!esp->inplace) { 354 int allocsize; 355 struct page_frag *pfrag = &x->xfrag; 356 357 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); 358 359 spin_lock_bh(&x->lock); 360 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 361 spin_unlock_bh(&x->lock); 362 goto error; 363 } 364 365 skb_shinfo(skb)->nr_frags = 1; 366 367 page = pfrag->page; 368 get_page(page); 369 /* replace page frags in skb with new page */ 370 __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); 371 pfrag->offset = pfrag->offset + allocsize; 372 spin_unlock_bh(&x->lock); 373 374 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); 375 skb_to_sgvec(skb, dsg, 376 (unsigned char *)esph - skb->data, 377 assoclen + ivlen + esp->clen + alen); 378 } 379 380 if ((x->props.flags & XFRM_STATE_ESN)) 381 aead_request_set_callback(req, 0, esp_output_done_esn, skb); 382 else 383 aead_request_set_callback(req, 0, esp_output_done, skb); 384 385 aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv); 386 aead_request_set_ad(req, assoclen); 387 388 memset(iv, 0, ivlen); 389 memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8), 390 min(ivlen, 8)); 391 392 ESP_SKB_CB(skb)->tmp = tmp; 393 err = crypto_aead_encrypt(req); 394 395 switch (err) { 396 case -EINPROGRESS: 397 goto error; 398 399 case -EBUSY: 400 err = NET_XMIT_DROP; 401 break; 402 403 case 0: 404 if ((x->props.flags & XFRM_STATE_ESN)) 405 esp_output_restore_header(skb); 406 } 407 408 if (sg != dsg) 409 esp_ssg_unref(x, tmp); 410 kfree(tmp); 411 412 error: 413 return err; 414 } 415 EXPORT_SYMBOL_GPL(esp6_output_tail); 416 417 static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) 418 { 419 int alen; 420 int blksize; 421 struct ip_esp_hdr *esph; 422 struct crypto_aead *aead; 423 struct esp_info esp; 424 425 esp.inplace = true; 426 427 esp.proto = *skb_mac_header(skb); 428 *skb_mac_header(skb) = IPPROTO_ESP; 429 430 /* skb is pure payload to encrypt */ 431 432 aead = x->data; 433 alen = crypto_aead_authsize(aead); 434 435 esp.tfclen = 0; 436 if (x->tfcpad) { 437 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); 438 u32 padto; 439 440 padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached)); 441 if (skb->len < padto) 442 esp.tfclen = padto - skb->len; 443 } 444 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 445 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); 446 esp.plen = esp.clen - skb->len - esp.tfclen; 447 esp.tailen = esp.tfclen + esp.plen + alen; 448 449 esp.nfrags = esp6_output_head(x, skb, &esp); 450 if (esp.nfrags < 0) 451 return esp.nfrags; 452 453 esph = ip_esp_hdr(skb); 454 esph->spi = x->id.spi; 455 456 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 457 esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + 458 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); 459 460 skb_push(skb, -skb_network_offset(skb)); 461 462 return esp6_output_tail(x, skb, &esp); 463 } 464 465 int esp6_input_done2(struct sk_buff *skb, int err) 466 { 467 struct xfrm_state *x = xfrm_input_state(skb); 468 struct xfrm_offload *xo = xfrm_offload(skb); 469 struct crypto_aead *aead = x->data; 470 int alen = crypto_aead_authsize(aead); 471 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 472 int elen = skb->len - hlen; 473 int hdr_len = skb_network_header_len(skb); 474 int padlen; 475 u8 nexthdr[2]; 476 477 if (!xo || (xo && !(xo->flags & CRYPTO_DONE))) 478 kfree(ESP_SKB_CB(skb)->tmp); 479 480 if (unlikely(err)) 481 goto out; 482 483 if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2)) 484 BUG(); 485 486 err = -EINVAL; 487 padlen = nexthdr[0]; 488 if (padlen + 2 + alen >= elen) { 489 net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", 490 padlen + 2, elen - alen); 491 goto out; 492 } 493 494 /* ... check padding bits here. Silly. :-) */ 495 496 pskb_trim(skb, skb->len - alen - padlen - 2); 497 __skb_pull(skb, hlen); 498 if (x->props.mode == XFRM_MODE_TUNNEL) 499 skb_reset_transport_header(skb); 500 else 501 skb_set_transport_header(skb, -hdr_len); 502 503 err = nexthdr[1]; 504 505 /* RFC4303: Drop dummy packets without any error */ 506 if (err == IPPROTO_NONE) 507 err = -EINVAL; 508 509 out: 510 return err; 511 } 512 EXPORT_SYMBOL_GPL(esp6_input_done2); 513 514 static void esp_input_done(struct crypto_async_request *base, int err) 515 { 516 struct sk_buff *skb = base->data; 517 518 xfrm_input_resume(skb, esp6_input_done2(skb, err)); 519 } 520 521 static void esp_input_restore_header(struct sk_buff *skb) 522 { 523 esp_restore_header(skb, 0); 524 __skb_pull(skb, 4); 525 } 526 527 static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) 528 { 529 struct xfrm_state *x = xfrm_input_state(skb); 530 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)skb->data; 531 532 /* For ESN we move the header forward by 4 bytes to 533 * accomodate the high bits. We will move it back after 534 * decryption. 535 */ 536 if ((x->props.flags & XFRM_STATE_ESN)) { 537 esph = (void *)skb_push(skb, 4); 538 *seqhi = esph->spi; 539 esph->spi = esph->seq_no; 540 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; 541 } 542 } 543 544 static void esp_input_done_esn(struct crypto_async_request *base, int err) 545 { 546 struct sk_buff *skb = base->data; 547 548 esp_input_restore_header(skb); 549 esp_input_done(base, err); 550 } 551 552 static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) 553 { 554 struct ip_esp_hdr *esph; 555 struct crypto_aead *aead = x->data; 556 struct aead_request *req; 557 struct sk_buff *trailer; 558 int ivlen = crypto_aead_ivsize(aead); 559 int elen = skb->len - sizeof(*esph) - ivlen; 560 int nfrags; 561 int assoclen; 562 int seqhilen; 563 int ret = 0; 564 void *tmp; 565 __be32 *seqhi; 566 u8 *iv; 567 struct scatterlist *sg; 568 569 if (!pskb_may_pull(skb, sizeof(*esph) + ivlen)) { 570 ret = -EINVAL; 571 goto out; 572 } 573 574 if (elen <= 0) { 575 ret = -EINVAL; 576 goto out; 577 } 578 579 assoclen = sizeof(*esph); 580 seqhilen = 0; 581 582 if (x->props.flags & XFRM_STATE_ESN) { 583 seqhilen += sizeof(__be32); 584 assoclen += seqhilen; 585 } 586 587 if (!skb_cloned(skb)) { 588 if (!skb_is_nonlinear(skb)) { 589 nfrags = 1; 590 591 goto skip_cow; 592 } else if (!skb_has_frag_list(skb)) { 593 nfrags = skb_shinfo(skb)->nr_frags; 594 nfrags++; 595 596 goto skip_cow; 597 } 598 } 599 600 nfrags = skb_cow_data(skb, 0, &trailer); 601 if (nfrags < 0) { 602 ret = -EINVAL; 603 goto out; 604 } 605 606 skip_cow: 607 ret = -ENOMEM; 608 tmp = esp_alloc_tmp(aead, nfrags, seqhilen); 609 if (!tmp) 610 goto out; 611 612 ESP_SKB_CB(skb)->tmp = tmp; 613 seqhi = esp_tmp_seqhi(tmp); 614 iv = esp_tmp_iv(aead, tmp, seqhilen); 615 req = esp_tmp_req(aead, iv); 616 sg = esp_req_sg(aead, req); 617 618 esp_input_set_header(skb, seqhi); 619 620 sg_init_table(sg, nfrags); 621 skb_to_sgvec(skb, sg, 0, skb->len); 622 623 skb->ip_summed = CHECKSUM_NONE; 624 625 if ((x->props.flags & XFRM_STATE_ESN)) 626 aead_request_set_callback(req, 0, esp_input_done_esn, skb); 627 else 628 aead_request_set_callback(req, 0, esp_input_done, skb); 629 630 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); 631 aead_request_set_ad(req, assoclen); 632 633 ret = crypto_aead_decrypt(req); 634 if (ret == -EINPROGRESS) 635 goto out; 636 637 if ((x->props.flags & XFRM_STATE_ESN)) 638 esp_input_restore_header(skb); 639 640 ret = esp6_input_done2(skb, ret); 641 642 out: 643 return ret; 644 } 645 646 static u32 esp6_get_mtu(struct xfrm_state *x, int mtu) 647 { 648 struct crypto_aead *aead = x->data; 649 u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 650 unsigned int net_adj; 651 652 if (x->props.mode != XFRM_MODE_TUNNEL) 653 net_adj = sizeof(struct ipv6hdr); 654 else 655 net_adj = 0; 656 657 return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - 658 net_adj) & ~(blksize - 1)) + net_adj - 2; 659 } 660 661 static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 662 u8 type, u8 code, int offset, __be32 info) 663 { 664 struct net *net = dev_net(skb->dev); 665 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 666 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); 667 struct xfrm_state *x; 668 669 if (type != ICMPV6_PKT_TOOBIG && 670 type != NDISC_REDIRECT) 671 return 0; 672 673 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 674 esph->spi, IPPROTO_ESP, AF_INET6); 675 if (!x) 676 return 0; 677 678 if (type == NDISC_REDIRECT) 679 ip6_redirect(skb, net, skb->dev->ifindex, 0, 680 sock_net_uid(net, NULL)); 681 else 682 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 683 xfrm_state_put(x); 684 685 return 0; 686 } 687 688 static void esp6_destroy(struct xfrm_state *x) 689 { 690 struct crypto_aead *aead = x->data; 691 692 if (!aead) 693 return; 694 695 crypto_free_aead(aead); 696 } 697 698 static int esp_init_aead(struct xfrm_state *x) 699 { 700 char aead_name[CRYPTO_MAX_ALG_NAME]; 701 struct crypto_aead *aead; 702 int err; 703 u32 mask = 0; 704 705 err = -ENAMETOOLONG; 706 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", 707 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) 708 goto error; 709 710 if (x->xso.offload_handle) 711 mask |= CRYPTO_ALG_ASYNC; 712 713 aead = crypto_alloc_aead(aead_name, 0, mask); 714 err = PTR_ERR(aead); 715 if (IS_ERR(aead)) 716 goto error; 717 718 x->data = aead; 719 720 err = crypto_aead_setkey(aead, x->aead->alg_key, 721 (x->aead->alg_key_len + 7) / 8); 722 if (err) 723 goto error; 724 725 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); 726 if (err) 727 goto error; 728 729 error: 730 return err; 731 } 732 733 static int esp_init_authenc(struct xfrm_state *x) 734 { 735 struct crypto_aead *aead; 736 struct crypto_authenc_key_param *param; 737 struct rtattr *rta; 738 char *key; 739 char *p; 740 char authenc_name[CRYPTO_MAX_ALG_NAME]; 741 unsigned int keylen; 742 int err; 743 u32 mask = 0; 744 745 err = -EINVAL; 746 if (!x->ealg) 747 goto error; 748 749 err = -ENAMETOOLONG; 750 751 if ((x->props.flags & XFRM_STATE_ESN)) { 752 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 753 "%s%sauthencesn(%s,%s)%s", 754 x->geniv ?: "", x->geniv ? "(" : "", 755 x->aalg ? x->aalg->alg_name : "digest_null", 756 x->ealg->alg_name, 757 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) 758 goto error; 759 } else { 760 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 761 "%s%sauthenc(%s,%s)%s", 762 x->geniv ?: "", x->geniv ? "(" : "", 763 x->aalg ? x->aalg->alg_name : "digest_null", 764 x->ealg->alg_name, 765 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) 766 goto error; 767 } 768 769 if (x->xso.offload_handle) 770 mask |= CRYPTO_ALG_ASYNC; 771 772 aead = crypto_alloc_aead(authenc_name, 0, mask); 773 err = PTR_ERR(aead); 774 if (IS_ERR(aead)) 775 goto error; 776 777 x->data = aead; 778 779 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + 780 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); 781 err = -ENOMEM; 782 key = kmalloc(keylen, GFP_KERNEL); 783 if (!key) 784 goto error; 785 786 p = key; 787 rta = (void *)p; 788 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 789 rta->rta_len = RTA_LENGTH(sizeof(*param)); 790 param = RTA_DATA(rta); 791 p += RTA_SPACE(sizeof(*param)); 792 793 if (x->aalg) { 794 struct xfrm_algo_desc *aalg_desc; 795 796 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); 797 p += (x->aalg->alg_key_len + 7) / 8; 798 799 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 800 BUG_ON(!aalg_desc); 801 802 err = -EINVAL; 803 if (aalg_desc->uinfo.auth.icv_fullbits / 8 != 804 crypto_aead_authsize(aead)) { 805 pr_info("ESP: %s digestsize %u != %hu\n", 806 x->aalg->alg_name, 807 crypto_aead_authsize(aead), 808 aalg_desc->uinfo.auth.icv_fullbits / 8); 809 goto free_key; 810 } 811 812 err = crypto_aead_setauthsize( 813 aead, x->aalg->alg_trunc_len / 8); 814 if (err) 815 goto free_key; 816 } 817 818 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); 819 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); 820 821 err = crypto_aead_setkey(aead, key, keylen); 822 823 free_key: 824 kfree(key); 825 826 error: 827 return err; 828 } 829 830 static int esp6_init_state(struct xfrm_state *x) 831 { 832 struct crypto_aead *aead; 833 u32 align; 834 int err; 835 836 if (x->encap) 837 return -EINVAL; 838 839 x->data = NULL; 840 841 if (x->aead) 842 err = esp_init_aead(x); 843 else 844 err = esp_init_authenc(x); 845 846 if (err) 847 goto error; 848 849 aead = x->data; 850 851 x->props.header_len = sizeof(struct ip_esp_hdr) + 852 crypto_aead_ivsize(aead); 853 switch (x->props.mode) { 854 case XFRM_MODE_BEET: 855 if (x->sel.family != AF_INET6) 856 x->props.header_len += IPV4_BEET_PHMAXLEN + 857 (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); 858 break; 859 case XFRM_MODE_TRANSPORT: 860 break; 861 case XFRM_MODE_TUNNEL: 862 x->props.header_len += sizeof(struct ipv6hdr); 863 break; 864 default: 865 goto error; 866 } 867 868 align = ALIGN(crypto_aead_blocksize(aead), 4); 869 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); 870 871 error: 872 return err; 873 } 874 875 static int esp6_rcv_cb(struct sk_buff *skb, int err) 876 { 877 return 0; 878 } 879 880 static const struct xfrm_type esp6_type = { 881 .description = "ESP6", 882 .owner = THIS_MODULE, 883 .proto = IPPROTO_ESP, 884 .flags = XFRM_TYPE_REPLAY_PROT, 885 .init_state = esp6_init_state, 886 .destructor = esp6_destroy, 887 .get_mtu = esp6_get_mtu, 888 .input = esp6_input, 889 .output = esp6_output, 890 .hdr_offset = xfrm6_find_1stfragopt, 891 }; 892 893 static struct xfrm6_protocol esp6_protocol = { 894 .handler = xfrm6_rcv, 895 .cb_handler = esp6_rcv_cb, 896 .err_handler = esp6_err, 897 .priority = 0, 898 }; 899 900 static int __init esp6_init(void) 901 { 902 if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { 903 pr_info("%s: can't add xfrm type\n", __func__); 904 return -EAGAIN; 905 } 906 if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { 907 pr_info("%s: can't add protocol\n", __func__); 908 xfrm_unregister_type(&esp6_type, AF_INET6); 909 return -EAGAIN; 910 } 911 912 return 0; 913 } 914 915 static void __exit esp6_fini(void) 916 { 917 if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) 918 pr_info("%s: can't remove protocol\n", __func__); 919 if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0) 920 pr_info("%s: can't remove xfrm type\n", __func__); 921 } 922 923 module_init(esp6_init); 924 module_exit(esp6_fini); 925 926 MODULE_LICENSE("GPL"); 927 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP); 928