1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C)2002 USAGI/WIDE Project 4 * 5 * Authors 6 * 7 * Mitsuru KANDA @USAGI : IPv6 Support 8 * Kazunori MIYAZAWA @USAGI : 9 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 10 * 11 * This file is derived from net/ipv4/esp.c 12 */ 13 14 #define pr_fmt(fmt) "IPv6: " fmt 15 16 #include <crypto/aead.h> 17 #include <crypto/authenc.h> 18 #include <linux/err.h> 19 #include <linux/module.h> 20 #include <net/ip.h> 21 #include <net/xfrm.h> 22 #include <net/esp.h> 23 #include <linux/scatterlist.h> 24 #include <linux/kernel.h> 25 #include <linux/pfkeyv2.h> 26 #include <linux/random.h> 27 #include <linux/slab.h> 28 #include <linux/spinlock.h> 29 #include <net/ip6_route.h> 30 #include <net/icmp.h> 31 #include <net/ipv6.h> 32 #include <net/protocol.h> 33 #include <linux/icmpv6.h> 34 35 #include <linux/highmem.h> 36 37 struct esp_skb_cb { 38 struct xfrm_skb_cb xfrm; 39 void *tmp; 40 }; 41 42 #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) 43 44 /* 45 * Allocate an AEAD request structure with extra space for SG and IV. 46 * 47 * For alignment considerations the upper 32 bits of the sequence number are 48 * placed at the front, if present. Followed by the IV, the request and finally 49 * the SG list. 50 * 51 * TODO: Use spare space in skb for this where possible. 52 */ 53 static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqihlen) 54 { 55 unsigned int len; 56 57 len = seqihlen; 58 59 len += crypto_aead_ivsize(aead); 60 61 if (len) { 62 len += crypto_aead_alignmask(aead) & 63 ~(crypto_tfm_ctx_alignment() - 1); 64 len = ALIGN(len, crypto_tfm_ctx_alignment()); 65 } 66 67 len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); 68 len = ALIGN(len, __alignof__(struct scatterlist)); 69 70 len += sizeof(struct scatterlist) * nfrags; 71 72 return kmalloc(len, GFP_ATOMIC); 73 } 74 75 static inline __be32 *esp_tmp_seqhi(void *tmp) 76 { 77 return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); 78 } 79 80 static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) 81 { 82 return crypto_aead_ivsize(aead) ? 83 PTR_ALIGN((u8 *)tmp + seqhilen, 84 crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; 85 } 86 87 static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) 88 { 89 struct aead_request *req; 90 91 req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), 92 crypto_tfm_ctx_alignment()); 93 aead_request_set_tfm(req, aead); 94 return req; 95 } 96 97 static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, 98 struct aead_request *req) 99 { 100 return (void *)ALIGN((unsigned long)(req + 1) + 101 crypto_aead_reqsize(aead), 102 __alignof__(struct scatterlist)); 103 } 104 105 static void esp_ssg_unref(struct xfrm_state *x, void *tmp) 106 { 107 struct crypto_aead *aead = x->data; 108 int seqhilen = 0; 109 u8 *iv; 110 struct aead_request *req; 111 struct scatterlist *sg; 112 113 if (x->props.flags & XFRM_STATE_ESN) 114 seqhilen += sizeof(__be32); 115 116 iv = esp_tmp_iv(aead, tmp, seqhilen); 117 req = esp_tmp_req(aead, iv); 118 119 /* Unref skb_frag_pages in the src scatterlist if necessary. 120 * Skip the first sg which comes from skb->data. 121 */ 122 if (req->src != req->dst) 123 for (sg = sg_next(req->src); sg; sg = sg_next(sg)) 124 put_page(sg_page(sg)); 125 } 126 127 static void esp_output_done(struct crypto_async_request *base, int err) 128 { 129 struct sk_buff *skb = base->data; 130 struct xfrm_offload *xo = xfrm_offload(skb); 131 void *tmp; 132 struct xfrm_state *x; 133 134 if (xo && (xo->flags & XFRM_DEV_RESUME)) { 135 struct sec_path *sp = skb_sec_path(skb); 136 137 x = sp->xvec[sp->len - 1]; 138 } else { 139 x = skb_dst(skb)->xfrm; 140 } 141 142 tmp = ESP_SKB_CB(skb)->tmp; 143 esp_ssg_unref(x, tmp); 144 kfree(tmp); 145 146 if (xo && (xo->flags & XFRM_DEV_RESUME)) { 147 if (err) { 148 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR); 149 kfree_skb(skb); 150 return; 151 } 152 153 skb_push(skb, skb->data - skb_mac_header(skb)); 154 secpath_reset(skb); 155 xfrm_dev_resume(skb); 156 } else { 157 xfrm_output_resume(skb, err); 158 } 159 } 160 161 /* Move ESP header back into place. */ 162 static void esp_restore_header(struct sk_buff *skb, unsigned int offset) 163 { 164 struct ip_esp_hdr *esph = (void *)(skb->data + offset); 165 void *tmp = ESP_SKB_CB(skb)->tmp; 166 __be32 *seqhi = esp_tmp_seqhi(tmp); 167 168 esph->seq_no = esph->spi; 169 esph->spi = *seqhi; 170 } 171 172 static void esp_output_restore_header(struct sk_buff *skb) 173 { 174 esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); 175 } 176 177 static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb, 178 struct xfrm_state *x, 179 struct ip_esp_hdr *esph, 180 __be32 *seqhi) 181 { 182 /* For ESN we move the header forward by 4 bytes to 183 * accomodate the high bits. We will move it back after 184 * encryption. 185 */ 186 if ((x->props.flags & XFRM_STATE_ESN)) { 187 struct xfrm_offload *xo = xfrm_offload(skb); 188 189 esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); 190 *seqhi = esph->spi; 191 if (xo) 192 esph->seq_no = htonl(xo->seq.hi); 193 else 194 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); 195 } 196 197 esph->spi = x->id.spi; 198 199 return esph; 200 } 201 202 static void esp_output_done_esn(struct crypto_async_request *base, int err) 203 { 204 struct sk_buff *skb = base->data; 205 206 esp_output_restore_header(skb); 207 esp_output_done(base, err); 208 } 209 210 int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) 211 { 212 u8 *tail; 213 u8 *vaddr; 214 int nfrags; 215 struct page *page; 216 struct sk_buff *trailer; 217 int tailen = esp->tailen; 218 219 if (!skb_cloned(skb)) { 220 if (tailen <= skb_tailroom(skb)) { 221 nfrags = 1; 222 trailer = skb; 223 tail = skb_tail_pointer(trailer); 224 225 goto skip_cow; 226 } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) 227 && !skb_has_frag_list(skb)) { 228 int allocsize; 229 struct sock *sk = skb->sk; 230 struct page_frag *pfrag = &x->xfrag; 231 232 esp->inplace = false; 233 234 allocsize = ALIGN(tailen, L1_CACHE_BYTES); 235 236 spin_lock_bh(&x->lock); 237 238 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 239 spin_unlock_bh(&x->lock); 240 goto cow; 241 } 242 243 page = pfrag->page; 244 get_page(page); 245 246 vaddr = kmap_atomic(page); 247 248 tail = vaddr + pfrag->offset; 249 250 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); 251 252 kunmap_atomic(vaddr); 253 254 nfrags = skb_shinfo(skb)->nr_frags; 255 256 __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, 257 tailen); 258 skb_shinfo(skb)->nr_frags = ++nfrags; 259 260 pfrag->offset = pfrag->offset + allocsize; 261 262 spin_unlock_bh(&x->lock); 263 264 nfrags++; 265 266 skb->len += tailen; 267 skb->data_len += tailen; 268 skb->truesize += tailen; 269 if (sk && sk_fullsock(sk)) 270 refcount_add(tailen, &sk->sk_wmem_alloc); 271 272 goto out; 273 } 274 } 275 276 cow: 277 nfrags = skb_cow_data(skb, tailen, &trailer); 278 if (nfrags < 0) 279 goto out; 280 tail = skb_tail_pointer(trailer); 281 282 skip_cow: 283 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); 284 pskb_put(skb, trailer, tailen); 285 286 out: 287 return nfrags; 288 } 289 EXPORT_SYMBOL_GPL(esp6_output_head); 290 291 int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) 292 { 293 u8 *iv; 294 int alen; 295 void *tmp; 296 int ivlen; 297 int assoclen; 298 int seqhilen; 299 __be32 *seqhi; 300 struct page *page; 301 struct ip_esp_hdr *esph; 302 struct aead_request *req; 303 struct crypto_aead *aead; 304 struct scatterlist *sg, *dsg; 305 int err = -ENOMEM; 306 307 assoclen = sizeof(struct ip_esp_hdr); 308 seqhilen = 0; 309 310 if (x->props.flags & XFRM_STATE_ESN) { 311 seqhilen += sizeof(__be32); 312 assoclen += sizeof(__be32); 313 } 314 315 aead = x->data; 316 alen = crypto_aead_authsize(aead); 317 ivlen = crypto_aead_ivsize(aead); 318 319 tmp = esp_alloc_tmp(aead, esp->nfrags + 2, seqhilen); 320 if (!tmp) 321 goto error; 322 323 seqhi = esp_tmp_seqhi(tmp); 324 iv = esp_tmp_iv(aead, tmp, seqhilen); 325 req = esp_tmp_req(aead, iv); 326 sg = esp_req_sg(aead, req); 327 328 if (esp->inplace) 329 dsg = sg; 330 else 331 dsg = &sg[esp->nfrags]; 332 333 esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi); 334 335 sg_init_table(sg, esp->nfrags); 336 err = skb_to_sgvec(skb, sg, 337 (unsigned char *)esph - skb->data, 338 assoclen + ivlen + esp->clen + alen); 339 if (unlikely(err < 0)) 340 goto error_free; 341 342 if (!esp->inplace) { 343 int allocsize; 344 struct page_frag *pfrag = &x->xfrag; 345 346 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); 347 348 spin_lock_bh(&x->lock); 349 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 350 spin_unlock_bh(&x->lock); 351 goto error_free; 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 spin_unlock_bh(&x->lock); 362 363 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); 364 err = skb_to_sgvec(skb, dsg, 365 (unsigned char *)esph - skb->data, 366 assoclen + ivlen + esp->clen + alen); 367 if (unlikely(err < 0)) 368 goto error_free; 369 } 370 371 if ((x->props.flags & XFRM_STATE_ESN)) 372 aead_request_set_callback(req, 0, esp_output_done_esn, skb); 373 else 374 aead_request_set_callback(req, 0, esp_output_done, skb); 375 376 aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv); 377 aead_request_set_ad(req, assoclen); 378 379 memset(iv, 0, ivlen); 380 memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8), 381 min(ivlen, 8)); 382 383 ESP_SKB_CB(skb)->tmp = tmp; 384 err = crypto_aead_encrypt(req); 385 386 switch (err) { 387 case -EINPROGRESS: 388 goto error; 389 390 case -ENOSPC: 391 err = NET_XMIT_DROP; 392 break; 393 394 case 0: 395 if ((x->props.flags & XFRM_STATE_ESN)) 396 esp_output_restore_header(skb); 397 } 398 399 if (sg != dsg) 400 esp_ssg_unref(x, tmp); 401 402 error_free: 403 kfree(tmp); 404 error: 405 return err; 406 } 407 EXPORT_SYMBOL_GPL(esp6_output_tail); 408 409 static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) 410 { 411 int alen; 412 int blksize; 413 struct ip_esp_hdr *esph; 414 struct crypto_aead *aead; 415 struct esp_info esp; 416 417 esp.inplace = true; 418 419 esp.proto = *skb_mac_header(skb); 420 *skb_mac_header(skb) = IPPROTO_ESP; 421 422 /* skb is pure payload to encrypt */ 423 424 aead = x->data; 425 alen = crypto_aead_authsize(aead); 426 427 esp.tfclen = 0; 428 if (x->tfcpad) { 429 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); 430 u32 padto; 431 432 padto = min(x->tfcpad, xfrm_state_mtu(x, dst->child_mtu_cached)); 433 if (skb->len < padto) 434 esp.tfclen = padto - skb->len; 435 } 436 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 437 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); 438 esp.plen = esp.clen - skb->len - esp.tfclen; 439 esp.tailen = esp.tfclen + esp.plen + alen; 440 441 esp.nfrags = esp6_output_head(x, skb, &esp); 442 if (esp.nfrags < 0) 443 return esp.nfrags; 444 445 esph = ip_esp_hdr(skb); 446 esph->spi = x->id.spi; 447 448 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 449 esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + 450 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); 451 452 skb_push(skb, -skb_network_offset(skb)); 453 454 return esp6_output_tail(x, skb, &esp); 455 } 456 457 static inline int esp_remove_trailer(struct sk_buff *skb) 458 { 459 struct xfrm_state *x = xfrm_input_state(skb); 460 struct xfrm_offload *xo = xfrm_offload(skb); 461 struct crypto_aead *aead = x->data; 462 int alen, hlen, elen; 463 int padlen, trimlen; 464 __wsum csumdiff; 465 u8 nexthdr[2]; 466 int ret; 467 468 alen = crypto_aead_authsize(aead); 469 hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 470 elen = skb->len - hlen; 471 472 if (xo && (xo->flags & XFRM_ESP_NO_TRAILER)) { 473 ret = xo->proto; 474 goto out; 475 } 476 477 ret = skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2); 478 BUG_ON(ret); 479 480 ret = -EINVAL; 481 padlen = nexthdr[0]; 482 if (padlen + 2 + alen >= elen) { 483 net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", 484 padlen + 2, elen - alen); 485 goto out; 486 } 487 488 trimlen = alen + padlen + 2; 489 if (skb->ip_summed == CHECKSUM_COMPLETE) { 490 csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0); 491 skb->csum = csum_block_sub(skb->csum, csumdiff, 492 skb->len - trimlen); 493 } 494 pskb_trim(skb, skb->len - trimlen); 495 496 ret = nexthdr[1]; 497 498 out: 499 return ret; 500 } 501 502 int esp6_input_done2(struct sk_buff *skb, int err) 503 { 504 struct xfrm_state *x = xfrm_input_state(skb); 505 struct xfrm_offload *xo = xfrm_offload(skb); 506 struct crypto_aead *aead = x->data; 507 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 508 int hdr_len = skb_network_header_len(skb); 509 510 if (!xo || (xo && !(xo->flags & CRYPTO_DONE))) 511 kfree(ESP_SKB_CB(skb)->tmp); 512 513 if (unlikely(err)) 514 goto out; 515 516 err = esp_remove_trailer(skb); 517 if (unlikely(err < 0)) 518 goto out; 519 520 skb_postpull_rcsum(skb, skb_network_header(skb), 521 skb_network_header_len(skb)); 522 skb_pull_rcsum(skb, hlen); 523 if (x->props.mode == XFRM_MODE_TUNNEL) 524 skb_reset_transport_header(skb); 525 else 526 skb_set_transport_header(skb, -hdr_len); 527 528 /* RFC4303: Drop dummy packets without any error */ 529 if (err == IPPROTO_NONE) 530 err = -EINVAL; 531 532 out: 533 return err; 534 } 535 EXPORT_SYMBOL_GPL(esp6_input_done2); 536 537 static void esp_input_done(struct crypto_async_request *base, int err) 538 { 539 struct sk_buff *skb = base->data; 540 541 xfrm_input_resume(skb, esp6_input_done2(skb, err)); 542 } 543 544 static void esp_input_restore_header(struct sk_buff *skb) 545 { 546 esp_restore_header(skb, 0); 547 __skb_pull(skb, 4); 548 } 549 550 static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) 551 { 552 struct xfrm_state *x = xfrm_input_state(skb); 553 554 /* For ESN we move the header forward by 4 bytes to 555 * accomodate the high bits. We will move it back after 556 * decryption. 557 */ 558 if ((x->props.flags & XFRM_STATE_ESN)) { 559 struct ip_esp_hdr *esph = skb_push(skb, 4); 560 561 *seqhi = esph->spi; 562 esph->spi = esph->seq_no; 563 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; 564 } 565 } 566 567 static void esp_input_done_esn(struct crypto_async_request *base, int err) 568 { 569 struct sk_buff *skb = base->data; 570 571 esp_input_restore_header(skb); 572 esp_input_done(base, err); 573 } 574 575 static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) 576 { 577 struct crypto_aead *aead = x->data; 578 struct aead_request *req; 579 struct sk_buff *trailer; 580 int ivlen = crypto_aead_ivsize(aead); 581 int elen = skb->len - sizeof(struct ip_esp_hdr) - ivlen; 582 int nfrags; 583 int assoclen; 584 int seqhilen; 585 int ret = 0; 586 void *tmp; 587 __be32 *seqhi; 588 u8 *iv; 589 struct scatterlist *sg; 590 591 if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + ivlen)) { 592 ret = -EINVAL; 593 goto out; 594 } 595 596 if (elen <= 0) { 597 ret = -EINVAL; 598 goto out; 599 } 600 601 assoclen = sizeof(struct ip_esp_hdr); 602 seqhilen = 0; 603 604 if (x->props.flags & XFRM_STATE_ESN) { 605 seqhilen += sizeof(__be32); 606 assoclen += seqhilen; 607 } 608 609 if (!skb_cloned(skb)) { 610 if (!skb_is_nonlinear(skb)) { 611 nfrags = 1; 612 613 goto skip_cow; 614 } else if (!skb_has_frag_list(skb)) { 615 nfrags = skb_shinfo(skb)->nr_frags; 616 nfrags++; 617 618 goto skip_cow; 619 } 620 } 621 622 nfrags = skb_cow_data(skb, 0, &trailer); 623 if (nfrags < 0) { 624 ret = -EINVAL; 625 goto out; 626 } 627 628 skip_cow: 629 ret = -ENOMEM; 630 tmp = esp_alloc_tmp(aead, nfrags, seqhilen); 631 if (!tmp) 632 goto out; 633 634 ESP_SKB_CB(skb)->tmp = tmp; 635 seqhi = esp_tmp_seqhi(tmp); 636 iv = esp_tmp_iv(aead, tmp, seqhilen); 637 req = esp_tmp_req(aead, iv); 638 sg = esp_req_sg(aead, req); 639 640 esp_input_set_header(skb, seqhi); 641 642 sg_init_table(sg, nfrags); 643 ret = skb_to_sgvec(skb, sg, 0, skb->len); 644 if (unlikely(ret < 0)) { 645 kfree(tmp); 646 goto out; 647 } 648 649 skb->ip_summed = CHECKSUM_NONE; 650 651 if ((x->props.flags & XFRM_STATE_ESN)) 652 aead_request_set_callback(req, 0, esp_input_done_esn, skb); 653 else 654 aead_request_set_callback(req, 0, esp_input_done, skb); 655 656 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); 657 aead_request_set_ad(req, assoclen); 658 659 ret = crypto_aead_decrypt(req); 660 if (ret == -EINPROGRESS) 661 goto out; 662 663 if ((x->props.flags & XFRM_STATE_ESN)) 664 esp_input_restore_header(skb); 665 666 ret = esp6_input_done2(skb, ret); 667 668 out: 669 return ret; 670 } 671 672 static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 673 u8 type, u8 code, int offset, __be32 info) 674 { 675 struct net *net = dev_net(skb->dev); 676 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 677 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); 678 struct xfrm_state *x; 679 680 if (type != ICMPV6_PKT_TOOBIG && 681 type != NDISC_REDIRECT) 682 return 0; 683 684 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 685 esph->spi, IPPROTO_ESP, AF_INET6); 686 if (!x) 687 return 0; 688 689 if (type == NDISC_REDIRECT) 690 ip6_redirect(skb, net, skb->dev->ifindex, 0, 691 sock_net_uid(net, NULL)); 692 else 693 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 694 xfrm_state_put(x); 695 696 return 0; 697 } 698 699 static void esp6_destroy(struct xfrm_state *x) 700 { 701 struct crypto_aead *aead = x->data; 702 703 if (!aead) 704 return; 705 706 crypto_free_aead(aead); 707 } 708 709 static int esp_init_aead(struct xfrm_state *x) 710 { 711 char aead_name[CRYPTO_MAX_ALG_NAME]; 712 struct crypto_aead *aead; 713 int err; 714 715 err = -ENAMETOOLONG; 716 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", 717 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) 718 goto error; 719 720 aead = crypto_alloc_aead(aead_name, 0, 0); 721 err = PTR_ERR(aead); 722 if (IS_ERR(aead)) 723 goto error; 724 725 x->data = aead; 726 727 err = crypto_aead_setkey(aead, x->aead->alg_key, 728 (x->aead->alg_key_len + 7) / 8); 729 if (err) 730 goto error; 731 732 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); 733 if (err) 734 goto error; 735 736 error: 737 return err; 738 } 739 740 static int esp_init_authenc(struct xfrm_state *x) 741 { 742 struct crypto_aead *aead; 743 struct crypto_authenc_key_param *param; 744 struct rtattr *rta; 745 char *key; 746 char *p; 747 char authenc_name[CRYPTO_MAX_ALG_NAME]; 748 unsigned int keylen; 749 int err; 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 aead = crypto_alloc_aead(authenc_name, 0, 0); 776 err = PTR_ERR(aead); 777 if (IS_ERR(aead)) 778 goto error; 779 780 x->data = aead; 781 782 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + 783 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); 784 err = -ENOMEM; 785 key = kmalloc(keylen, GFP_KERNEL); 786 if (!key) 787 goto error; 788 789 p = key; 790 rta = (void *)p; 791 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 792 rta->rta_len = RTA_LENGTH(sizeof(*param)); 793 param = RTA_DATA(rta); 794 p += RTA_SPACE(sizeof(*param)); 795 796 if (x->aalg) { 797 struct xfrm_algo_desc *aalg_desc; 798 799 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); 800 p += (x->aalg->alg_key_len + 7) / 8; 801 802 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 803 BUG_ON(!aalg_desc); 804 805 err = -EINVAL; 806 if (aalg_desc->uinfo.auth.icv_fullbits / 8 != 807 crypto_aead_authsize(aead)) { 808 pr_info("ESP: %s digestsize %u != %hu\n", 809 x->aalg->alg_name, 810 crypto_aead_authsize(aead), 811 aalg_desc->uinfo.auth.icv_fullbits / 8); 812 goto free_key; 813 } 814 815 err = crypto_aead_setauthsize( 816 aead, x->aalg->alg_trunc_len / 8); 817 if (err) 818 goto free_key; 819 } 820 821 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); 822 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); 823 824 err = crypto_aead_setkey(aead, key, keylen); 825 826 free_key: 827 kfree(key); 828 829 error: 830 return err; 831 } 832 833 static int esp6_init_state(struct xfrm_state *x) 834 { 835 struct crypto_aead *aead; 836 u32 align; 837 int err; 838 839 if (x->encap) 840 return -EINVAL; 841 842 x->data = NULL; 843 844 if (x->aead) 845 err = esp_init_aead(x); 846 else 847 err = esp_init_authenc(x); 848 849 if (err) 850 goto error; 851 852 aead = x->data; 853 854 x->props.header_len = sizeof(struct ip_esp_hdr) + 855 crypto_aead_ivsize(aead); 856 switch (x->props.mode) { 857 case XFRM_MODE_BEET: 858 if (x->sel.family != AF_INET6) 859 x->props.header_len += IPV4_BEET_PHMAXLEN + 860 (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); 861 break; 862 default: 863 case XFRM_MODE_TRANSPORT: 864 break; 865 case XFRM_MODE_TUNNEL: 866 x->props.header_len += sizeof(struct ipv6hdr); 867 break; 868 } 869 870 align = ALIGN(crypto_aead_blocksize(aead), 4); 871 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); 872 873 error: 874 return err; 875 } 876 877 static int esp6_rcv_cb(struct sk_buff *skb, int err) 878 { 879 return 0; 880 } 881 882 static const struct xfrm_type esp6_type = { 883 .description = "ESP6", 884 .owner = THIS_MODULE, 885 .proto = IPPROTO_ESP, 886 .flags = XFRM_TYPE_REPLAY_PROT, 887 .init_state = esp6_init_state, 888 .destructor = esp6_destroy, 889 .input = esp6_input, 890 .output = esp6_output, 891 .hdr_offset = xfrm6_find_1stfragopt, 892 }; 893 894 static struct xfrm6_protocol esp6_protocol = { 895 .handler = xfrm6_rcv, 896 .cb_handler = esp6_rcv_cb, 897 .err_handler = esp6_err, 898 .priority = 0, 899 }; 900 901 static int __init esp6_init(void) 902 { 903 if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { 904 pr_info("%s: can't add xfrm type\n", __func__); 905 return -EAGAIN; 906 } 907 if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { 908 pr_info("%s: can't add protocol\n", __func__); 909 xfrm_unregister_type(&esp6_type, AF_INET6); 910 return -EAGAIN; 911 } 912 913 return 0; 914 } 915 916 static void __exit esp6_fini(void) 917 { 918 if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) 919 pr_info("%s: can't remove protocol\n", __func__); 920 xfrm_unregister_type(&esp6_type, AF_INET6); 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