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 err = skb_to_sgvec(skb, sg, 350 (unsigned char *)esph - skb->data, 351 assoclen + ivlen + esp->clen + alen); 352 if (unlikely(err < 0)) 353 goto error; 354 355 if (!esp->inplace) { 356 int allocsize; 357 struct page_frag *pfrag = &x->xfrag; 358 359 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); 360 361 spin_lock_bh(&x->lock); 362 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 363 spin_unlock_bh(&x->lock); 364 goto error; 365 } 366 367 skb_shinfo(skb)->nr_frags = 1; 368 369 page = pfrag->page; 370 get_page(page); 371 /* replace page frags in skb with new page */ 372 __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); 373 pfrag->offset = pfrag->offset + allocsize; 374 spin_unlock_bh(&x->lock); 375 376 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); 377 err = skb_to_sgvec(skb, dsg, 378 (unsigned char *)esph - skb->data, 379 assoclen + ivlen + esp->clen + alen); 380 if (unlikely(err < 0)) 381 goto error; 382 } 383 384 if ((x->props.flags & XFRM_STATE_ESN)) 385 aead_request_set_callback(req, 0, esp_output_done_esn, skb); 386 else 387 aead_request_set_callback(req, 0, esp_output_done, skb); 388 389 aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv); 390 aead_request_set_ad(req, assoclen); 391 392 memset(iv, 0, ivlen); 393 memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8), 394 min(ivlen, 8)); 395 396 ESP_SKB_CB(skb)->tmp = tmp; 397 err = crypto_aead_encrypt(req); 398 399 switch (err) { 400 case -EINPROGRESS: 401 goto error; 402 403 case -EBUSY: 404 err = NET_XMIT_DROP; 405 break; 406 407 case 0: 408 if ((x->props.flags & XFRM_STATE_ESN)) 409 esp_output_restore_header(skb); 410 } 411 412 if (sg != dsg) 413 esp_ssg_unref(x, tmp); 414 kfree(tmp); 415 416 error: 417 return err; 418 } 419 EXPORT_SYMBOL_GPL(esp6_output_tail); 420 421 static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) 422 { 423 int alen; 424 int blksize; 425 struct ip_esp_hdr *esph; 426 struct crypto_aead *aead; 427 struct esp_info esp; 428 429 esp.inplace = true; 430 431 esp.proto = *skb_mac_header(skb); 432 *skb_mac_header(skb) = IPPROTO_ESP; 433 434 /* skb is pure payload to encrypt */ 435 436 aead = x->data; 437 alen = crypto_aead_authsize(aead); 438 439 esp.tfclen = 0; 440 if (x->tfcpad) { 441 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); 442 u32 padto; 443 444 padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached)); 445 if (skb->len < padto) 446 esp.tfclen = padto - skb->len; 447 } 448 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 449 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); 450 esp.plen = esp.clen - skb->len - esp.tfclen; 451 esp.tailen = esp.tfclen + esp.plen + alen; 452 453 esp.nfrags = esp6_output_head(x, skb, &esp); 454 if (esp.nfrags < 0) 455 return esp.nfrags; 456 457 esph = ip_esp_hdr(skb); 458 esph->spi = x->id.spi; 459 460 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 461 esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + 462 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); 463 464 skb_push(skb, -skb_network_offset(skb)); 465 466 return esp6_output_tail(x, skb, &esp); 467 } 468 469 int esp6_input_done2(struct sk_buff *skb, int err) 470 { 471 struct xfrm_state *x = xfrm_input_state(skb); 472 struct xfrm_offload *xo = xfrm_offload(skb); 473 struct crypto_aead *aead = x->data; 474 int alen = crypto_aead_authsize(aead); 475 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 476 int elen = skb->len - hlen; 477 int hdr_len = skb_network_header_len(skb); 478 int padlen; 479 u8 nexthdr[2]; 480 481 if (!xo || (xo && !(xo->flags & CRYPTO_DONE))) 482 kfree(ESP_SKB_CB(skb)->tmp); 483 484 if (unlikely(err)) 485 goto out; 486 487 if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2)) 488 BUG(); 489 490 err = -EINVAL; 491 padlen = nexthdr[0]; 492 if (padlen + 2 + alen >= elen) { 493 net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", 494 padlen + 2, elen - alen); 495 goto out; 496 } 497 498 /* ... check padding bits here. Silly. :-) */ 499 500 pskb_trim(skb, skb->len - alen - padlen - 2); 501 __skb_pull(skb, hlen); 502 if (x->props.mode == XFRM_MODE_TUNNEL) 503 skb_reset_transport_header(skb); 504 else 505 skb_set_transport_header(skb, -hdr_len); 506 507 err = nexthdr[1]; 508 509 /* RFC4303: Drop dummy packets without any error */ 510 if (err == IPPROTO_NONE) 511 err = -EINVAL; 512 513 out: 514 return err; 515 } 516 EXPORT_SYMBOL_GPL(esp6_input_done2); 517 518 static void esp_input_done(struct crypto_async_request *base, int err) 519 { 520 struct sk_buff *skb = base->data; 521 522 xfrm_input_resume(skb, esp6_input_done2(skb, err)); 523 } 524 525 static void esp_input_restore_header(struct sk_buff *skb) 526 { 527 esp_restore_header(skb, 0); 528 __skb_pull(skb, 4); 529 } 530 531 static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) 532 { 533 struct xfrm_state *x = xfrm_input_state(skb); 534 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)skb->data; 535 536 /* For ESN we move the header forward by 4 bytes to 537 * accomodate the high bits. We will move it back after 538 * decryption. 539 */ 540 if ((x->props.flags & XFRM_STATE_ESN)) { 541 esph = skb_push(skb, 4); 542 *seqhi = esph->spi; 543 esph->spi = esph->seq_no; 544 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; 545 } 546 } 547 548 static void esp_input_done_esn(struct crypto_async_request *base, int err) 549 { 550 struct sk_buff *skb = base->data; 551 552 esp_input_restore_header(skb); 553 esp_input_done(base, err); 554 } 555 556 static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) 557 { 558 struct ip_esp_hdr *esph; 559 struct crypto_aead *aead = x->data; 560 struct aead_request *req; 561 struct sk_buff *trailer; 562 int ivlen = crypto_aead_ivsize(aead); 563 int elen = skb->len - sizeof(*esph) - ivlen; 564 int nfrags; 565 int assoclen; 566 int seqhilen; 567 int ret = 0; 568 void *tmp; 569 __be32 *seqhi; 570 u8 *iv; 571 struct scatterlist *sg; 572 573 if (!pskb_may_pull(skb, sizeof(*esph) + ivlen)) { 574 ret = -EINVAL; 575 goto out; 576 } 577 578 if (elen <= 0) { 579 ret = -EINVAL; 580 goto out; 581 } 582 583 assoclen = sizeof(*esph); 584 seqhilen = 0; 585 586 if (x->props.flags & XFRM_STATE_ESN) { 587 seqhilen += sizeof(__be32); 588 assoclen += seqhilen; 589 } 590 591 if (!skb_cloned(skb)) { 592 if (!skb_is_nonlinear(skb)) { 593 nfrags = 1; 594 595 goto skip_cow; 596 } else if (!skb_has_frag_list(skb)) { 597 nfrags = skb_shinfo(skb)->nr_frags; 598 nfrags++; 599 600 goto skip_cow; 601 } 602 } 603 604 nfrags = skb_cow_data(skb, 0, &trailer); 605 if (nfrags < 0) { 606 ret = -EINVAL; 607 goto out; 608 } 609 610 skip_cow: 611 ret = -ENOMEM; 612 tmp = esp_alloc_tmp(aead, nfrags, seqhilen); 613 if (!tmp) 614 goto out; 615 616 ESP_SKB_CB(skb)->tmp = tmp; 617 seqhi = esp_tmp_seqhi(tmp); 618 iv = esp_tmp_iv(aead, tmp, seqhilen); 619 req = esp_tmp_req(aead, iv); 620 sg = esp_req_sg(aead, req); 621 622 esp_input_set_header(skb, seqhi); 623 624 sg_init_table(sg, nfrags); 625 ret = skb_to_sgvec(skb, sg, 0, skb->len); 626 if (unlikely(ret < 0)) 627 goto out; 628 629 skb->ip_summed = CHECKSUM_NONE; 630 631 if ((x->props.flags & XFRM_STATE_ESN)) 632 aead_request_set_callback(req, 0, esp_input_done_esn, skb); 633 else 634 aead_request_set_callback(req, 0, esp_input_done, skb); 635 636 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); 637 aead_request_set_ad(req, assoclen); 638 639 ret = crypto_aead_decrypt(req); 640 if (ret == -EINPROGRESS) 641 goto out; 642 643 if ((x->props.flags & XFRM_STATE_ESN)) 644 esp_input_restore_header(skb); 645 646 ret = esp6_input_done2(skb, ret); 647 648 out: 649 return ret; 650 } 651 652 static u32 esp6_get_mtu(struct xfrm_state *x, int mtu) 653 { 654 struct crypto_aead *aead = x->data; 655 u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 656 unsigned int net_adj; 657 658 if (x->props.mode != XFRM_MODE_TUNNEL) 659 net_adj = sizeof(struct ipv6hdr); 660 else 661 net_adj = 0; 662 663 return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - 664 net_adj) & ~(blksize - 1)) + net_adj - 2; 665 } 666 667 static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 668 u8 type, u8 code, int offset, __be32 info) 669 { 670 struct net *net = dev_net(skb->dev); 671 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 672 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); 673 struct xfrm_state *x; 674 675 if (type != ICMPV6_PKT_TOOBIG && 676 type != NDISC_REDIRECT) 677 return 0; 678 679 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 680 esph->spi, IPPROTO_ESP, AF_INET6); 681 if (!x) 682 return 0; 683 684 if (type == NDISC_REDIRECT) 685 ip6_redirect(skb, net, skb->dev->ifindex, 0, 686 sock_net_uid(net, NULL)); 687 else 688 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 689 xfrm_state_put(x); 690 691 return 0; 692 } 693 694 static void esp6_destroy(struct xfrm_state *x) 695 { 696 struct crypto_aead *aead = x->data; 697 698 if (!aead) 699 return; 700 701 crypto_free_aead(aead); 702 } 703 704 static int esp_init_aead(struct xfrm_state *x) 705 { 706 char aead_name[CRYPTO_MAX_ALG_NAME]; 707 struct crypto_aead *aead; 708 int err; 709 u32 mask = 0; 710 711 err = -ENAMETOOLONG; 712 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", 713 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) 714 goto error; 715 716 if (x->xso.offload_handle) 717 mask |= CRYPTO_ALG_ASYNC; 718 719 aead = crypto_alloc_aead(aead_name, 0, mask); 720 err = PTR_ERR(aead); 721 if (IS_ERR(aead)) 722 goto error; 723 724 x->data = aead; 725 726 err = crypto_aead_setkey(aead, x->aead->alg_key, 727 (x->aead->alg_key_len + 7) / 8); 728 if (err) 729 goto error; 730 731 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); 732 if (err) 733 goto error; 734 735 error: 736 return err; 737 } 738 739 static int esp_init_authenc(struct xfrm_state *x) 740 { 741 struct crypto_aead *aead; 742 struct crypto_authenc_key_param *param; 743 struct rtattr *rta; 744 char *key; 745 char *p; 746 char authenc_name[CRYPTO_MAX_ALG_NAME]; 747 unsigned int keylen; 748 int err; 749 u32 mask = 0; 750 751 err = -EINVAL; 752 if (!x->ealg) 753 goto error; 754 755 err = -ENAMETOOLONG; 756 757 if ((x->props.flags & XFRM_STATE_ESN)) { 758 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 759 "%s%sauthencesn(%s,%s)%s", 760 x->geniv ?: "", x->geniv ? "(" : "", 761 x->aalg ? x->aalg->alg_name : "digest_null", 762 x->ealg->alg_name, 763 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) 764 goto error; 765 } else { 766 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 767 "%s%sauthenc(%s,%s)%s", 768 x->geniv ?: "", x->geniv ? "(" : "", 769 x->aalg ? x->aalg->alg_name : "digest_null", 770 x->ealg->alg_name, 771 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) 772 goto error; 773 } 774 775 if (x->xso.offload_handle) 776 mask |= CRYPTO_ALG_ASYNC; 777 778 aead = crypto_alloc_aead(authenc_name, 0, mask); 779 err = PTR_ERR(aead); 780 if (IS_ERR(aead)) 781 goto error; 782 783 x->data = aead; 784 785 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + 786 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); 787 err = -ENOMEM; 788 key = kmalloc(keylen, GFP_KERNEL); 789 if (!key) 790 goto error; 791 792 p = key; 793 rta = (void *)p; 794 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 795 rta->rta_len = RTA_LENGTH(sizeof(*param)); 796 param = RTA_DATA(rta); 797 p += RTA_SPACE(sizeof(*param)); 798 799 if (x->aalg) { 800 struct xfrm_algo_desc *aalg_desc; 801 802 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); 803 p += (x->aalg->alg_key_len + 7) / 8; 804 805 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 806 BUG_ON(!aalg_desc); 807 808 err = -EINVAL; 809 if (aalg_desc->uinfo.auth.icv_fullbits / 8 != 810 crypto_aead_authsize(aead)) { 811 pr_info("ESP: %s digestsize %u != %hu\n", 812 x->aalg->alg_name, 813 crypto_aead_authsize(aead), 814 aalg_desc->uinfo.auth.icv_fullbits / 8); 815 goto free_key; 816 } 817 818 err = crypto_aead_setauthsize( 819 aead, x->aalg->alg_trunc_len / 8); 820 if (err) 821 goto free_key; 822 } 823 824 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); 825 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); 826 827 err = crypto_aead_setkey(aead, key, keylen); 828 829 free_key: 830 kfree(key); 831 832 error: 833 return err; 834 } 835 836 static int esp6_init_state(struct xfrm_state *x) 837 { 838 struct crypto_aead *aead; 839 u32 align; 840 int err; 841 842 if (x->encap) 843 return -EINVAL; 844 845 x->data = NULL; 846 847 if (x->aead) 848 err = esp_init_aead(x); 849 else 850 err = esp_init_authenc(x); 851 852 if (err) 853 goto error; 854 855 aead = x->data; 856 857 x->props.header_len = sizeof(struct ip_esp_hdr) + 858 crypto_aead_ivsize(aead); 859 switch (x->props.mode) { 860 case XFRM_MODE_BEET: 861 if (x->sel.family != AF_INET6) 862 x->props.header_len += IPV4_BEET_PHMAXLEN + 863 (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); 864 break; 865 case XFRM_MODE_TRANSPORT: 866 break; 867 case XFRM_MODE_TUNNEL: 868 x->props.header_len += sizeof(struct ipv6hdr); 869 break; 870 default: 871 goto error; 872 } 873 874 align = ALIGN(crypto_aead_blocksize(aead), 4); 875 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); 876 877 error: 878 return err; 879 } 880 881 static int esp6_rcv_cb(struct sk_buff *skb, int err) 882 { 883 return 0; 884 } 885 886 static const struct xfrm_type esp6_type = { 887 .description = "ESP6", 888 .owner = THIS_MODULE, 889 .proto = IPPROTO_ESP, 890 .flags = XFRM_TYPE_REPLAY_PROT, 891 .init_state = esp6_init_state, 892 .destructor = esp6_destroy, 893 .get_mtu = esp6_get_mtu, 894 .input = esp6_input, 895 .output = esp6_output, 896 .hdr_offset = xfrm6_find_1stfragopt, 897 }; 898 899 static struct xfrm6_protocol esp6_protocol = { 900 .handler = xfrm6_rcv, 901 .cb_handler = esp6_rcv_cb, 902 .err_handler = esp6_err, 903 .priority = 0, 904 }; 905 906 static int __init esp6_init(void) 907 { 908 if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { 909 pr_info("%s: can't add xfrm type\n", __func__); 910 return -EAGAIN; 911 } 912 if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { 913 pr_info("%s: can't add protocol\n", __func__); 914 xfrm_unregister_type(&esp6_type, AF_INET6); 915 return -EAGAIN; 916 } 917 918 return 0; 919 } 920 921 static void __exit esp6_fini(void) 922 { 923 if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) 924 pr_info("%s: can't remove protocol\n", __func__); 925 if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0) 926 pr_info("%s: can't remove xfrm type\n", __func__); 927 } 928 929 module_init(esp6_init); 930 module_exit(esp6_fini); 931 932 MODULE_LICENSE("GPL"); 933 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP); 934