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 struct crypto_aead *aead = x->data; 122 int seqhilen = 0; 123 u8 *iv; 124 struct aead_request *req; 125 struct scatterlist *sg; 126 127 if (x->props.flags & XFRM_STATE_ESN) 128 seqhilen += sizeof(__be32); 129 130 iv = esp_tmp_iv(aead, tmp, seqhilen); 131 req = esp_tmp_req(aead, iv); 132 133 /* Unref skb_frag_pages in the src scatterlist if necessary. 134 * Skip the first sg which comes from skb->data. 135 */ 136 if (req->src != req->dst) 137 for (sg = sg_next(req->src); sg; sg = sg_next(sg)) 138 put_page(sg_page(sg)); 139 } 140 141 static void esp_output_done(struct crypto_async_request *base, int err) 142 { 143 struct sk_buff *skb = base->data; 144 void *tmp; 145 struct dst_entry *dst = skb_dst(skb); 146 struct xfrm_state *x = dst->xfrm; 147 148 tmp = ESP_SKB_CB(skb)->tmp; 149 esp_ssg_unref(x, tmp); 150 kfree(tmp); 151 xfrm_output_resume(skb, err); 152 } 153 154 /* Move ESP header back into place. */ 155 static void esp_restore_header(struct sk_buff *skb, unsigned int offset) 156 { 157 struct ip_esp_hdr *esph = (void *)(skb->data + offset); 158 void *tmp = ESP_SKB_CB(skb)->tmp; 159 __be32 *seqhi = esp_tmp_seqhi(tmp); 160 161 esph->seq_no = esph->spi; 162 esph->spi = *seqhi; 163 } 164 165 static void esp_output_restore_header(struct sk_buff *skb) 166 { 167 esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); 168 } 169 170 static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb, 171 struct xfrm_state *x, 172 struct ip_esp_hdr *esph, 173 __be32 *seqhi) 174 { 175 /* For ESN we move the header forward by 4 bytes to 176 * accomodate the high bits. We will move it back after 177 * encryption. 178 */ 179 if ((x->props.flags & XFRM_STATE_ESN)) { 180 struct xfrm_offload *xo = xfrm_offload(skb); 181 182 esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); 183 *seqhi = esph->spi; 184 if (xo) 185 esph->seq_no = htonl(xo->seq.hi); 186 else 187 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); 188 } 189 190 esph->spi = x->id.spi; 191 192 return esph; 193 } 194 195 static void esp_output_done_esn(struct crypto_async_request *base, int err) 196 { 197 struct sk_buff *skb = base->data; 198 199 esp_output_restore_header(skb); 200 esp_output_done(base, err); 201 } 202 203 static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) 204 { 205 /* Fill padding... */ 206 if (tfclen) { 207 memset(tail, 0, tfclen); 208 tail += tfclen; 209 } 210 do { 211 int i; 212 for (i = 0; i < plen - 2; i++) 213 tail[i] = i + 1; 214 } while (0); 215 tail[plen - 2] = plen - 2; 216 tail[plen - 1] = proto; 217 } 218 219 int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) 220 { 221 u8 *tail; 222 u8 *vaddr; 223 int nfrags; 224 struct page *page; 225 struct sk_buff *trailer; 226 int tailen = esp->tailen; 227 228 if (!skb_cloned(skb)) { 229 if (tailen <= skb_tailroom(skb)) { 230 nfrags = 1; 231 trailer = skb; 232 tail = skb_tail_pointer(trailer); 233 234 goto skip_cow; 235 } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) 236 && !skb_has_frag_list(skb)) { 237 int allocsize; 238 struct sock *sk = skb->sk; 239 struct page_frag *pfrag = &x->xfrag; 240 241 esp->inplace = false; 242 243 allocsize = ALIGN(tailen, L1_CACHE_BYTES); 244 245 spin_lock_bh(&x->lock); 246 247 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 248 spin_unlock_bh(&x->lock); 249 goto cow; 250 } 251 252 page = pfrag->page; 253 get_page(page); 254 255 vaddr = kmap_atomic(page); 256 257 tail = vaddr + pfrag->offset; 258 259 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); 260 261 kunmap_atomic(vaddr); 262 263 nfrags = skb_shinfo(skb)->nr_frags; 264 265 __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, 266 tailen); 267 skb_shinfo(skb)->nr_frags = ++nfrags; 268 269 pfrag->offset = pfrag->offset + allocsize; 270 271 spin_unlock_bh(&x->lock); 272 273 nfrags++; 274 275 skb->len += tailen; 276 skb->data_len += tailen; 277 skb->truesize += tailen; 278 if (sk) 279 refcount_add(tailen, &sk->sk_wmem_alloc); 280 281 goto out; 282 } 283 } 284 285 cow: 286 nfrags = skb_cow_data(skb, tailen, &trailer); 287 if (nfrags < 0) 288 goto out; 289 tail = skb_tail_pointer(trailer); 290 291 skip_cow: 292 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); 293 pskb_put(skb, trailer, tailen); 294 295 out: 296 return nfrags; 297 } 298 EXPORT_SYMBOL_GPL(esp6_output_head); 299 300 int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) 301 { 302 u8 *iv; 303 int alen; 304 void *tmp; 305 int ivlen; 306 int assoclen; 307 int seqhilen; 308 __be32 *seqhi; 309 struct page *page; 310 struct ip_esp_hdr *esph; 311 struct aead_request *req; 312 struct crypto_aead *aead; 313 struct scatterlist *sg, *dsg; 314 int err = -ENOMEM; 315 316 assoclen = sizeof(struct ip_esp_hdr); 317 seqhilen = 0; 318 319 if (x->props.flags & XFRM_STATE_ESN) { 320 seqhilen += sizeof(__be32); 321 assoclen += sizeof(__be32); 322 } 323 324 aead = x->data; 325 alen = crypto_aead_authsize(aead); 326 ivlen = crypto_aead_ivsize(aead); 327 328 tmp = esp_alloc_tmp(aead, esp->nfrags + 2, seqhilen); 329 if (!tmp) 330 goto error; 331 332 seqhi = esp_tmp_seqhi(tmp); 333 iv = esp_tmp_iv(aead, tmp, seqhilen); 334 req = esp_tmp_req(aead, iv); 335 sg = esp_req_sg(aead, req); 336 337 if (esp->inplace) 338 dsg = sg; 339 else 340 dsg = &sg[esp->nfrags]; 341 342 esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi); 343 344 sg_init_table(sg, esp->nfrags); 345 err = skb_to_sgvec(skb, sg, 346 (unsigned char *)esph - skb->data, 347 assoclen + ivlen + esp->clen + alen); 348 if (unlikely(err < 0)) 349 goto error_free; 350 351 if (!esp->inplace) { 352 int allocsize; 353 struct page_frag *pfrag = &x->xfrag; 354 355 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); 356 357 spin_lock_bh(&x->lock); 358 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { 359 spin_unlock_bh(&x->lock); 360 goto error_free; 361 } 362 363 skb_shinfo(skb)->nr_frags = 1; 364 365 page = pfrag->page; 366 get_page(page); 367 /* replace page frags in skb with new page */ 368 __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); 369 pfrag->offset = pfrag->offset + allocsize; 370 spin_unlock_bh(&x->lock); 371 372 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); 373 err = skb_to_sgvec(skb, dsg, 374 (unsigned char *)esph - skb->data, 375 assoclen + ivlen + esp->clen + alen); 376 if (unlikely(err < 0)) 377 goto error_free; 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 -ENOSPC: 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); 410 411 error_free: 412 kfree(tmp); 413 error: 414 return err; 415 } 416 EXPORT_SYMBOL_GPL(esp6_output_tail); 417 418 static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) 419 { 420 int alen; 421 int blksize; 422 struct ip_esp_hdr *esph; 423 struct crypto_aead *aead; 424 struct esp_info esp; 425 426 esp.inplace = true; 427 428 esp.proto = *skb_mac_header(skb); 429 *skb_mac_header(skb) = IPPROTO_ESP; 430 431 /* skb is pure payload to encrypt */ 432 433 aead = x->data; 434 alen = crypto_aead_authsize(aead); 435 436 esp.tfclen = 0; 437 if (x->tfcpad) { 438 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); 439 u32 padto; 440 441 padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached)); 442 if (skb->len < padto) 443 esp.tfclen = padto - skb->len; 444 } 445 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 446 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); 447 esp.plen = esp.clen - skb->len - esp.tfclen; 448 esp.tailen = esp.tfclen + esp.plen + alen; 449 450 esp.nfrags = esp6_output_head(x, skb, &esp); 451 if (esp.nfrags < 0) 452 return esp.nfrags; 453 454 esph = ip_esp_hdr(skb); 455 esph->spi = x->id.spi; 456 457 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); 458 esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + 459 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); 460 461 skb_push(skb, -skb_network_offset(skb)); 462 463 return esp6_output_tail(x, skb, &esp); 464 } 465 466 static inline int esp_remove_trailer(struct sk_buff *skb) 467 { 468 struct xfrm_state *x = xfrm_input_state(skb); 469 struct xfrm_offload *xo = xfrm_offload(skb); 470 struct crypto_aead *aead = x->data; 471 int alen, hlen, elen; 472 int padlen, trimlen; 473 __wsum csumdiff; 474 u8 nexthdr[2]; 475 int ret; 476 477 alen = crypto_aead_authsize(aead); 478 hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 479 elen = skb->len - hlen; 480 481 if (xo && (xo->flags & XFRM_ESP_NO_TRAILER)) { 482 ret = xo->proto; 483 goto out; 484 } 485 486 ret = skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2); 487 BUG_ON(ret); 488 489 ret = -EINVAL; 490 padlen = nexthdr[0]; 491 if (padlen + 2 + alen >= elen) { 492 net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", 493 padlen + 2, elen - alen); 494 goto out; 495 } 496 497 trimlen = alen + padlen + 2; 498 if (skb->ip_summed == CHECKSUM_COMPLETE) { 499 csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0); 500 skb->csum = csum_block_sub(skb->csum, csumdiff, 501 skb->len - trimlen); 502 } 503 pskb_trim(skb, skb->len - trimlen); 504 505 ret = nexthdr[1]; 506 507 out: 508 return ret; 509 } 510 511 int esp6_input_done2(struct sk_buff *skb, int err) 512 { 513 struct xfrm_state *x = xfrm_input_state(skb); 514 struct xfrm_offload *xo = xfrm_offload(skb); 515 struct crypto_aead *aead = x->data; 516 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); 517 int hdr_len = skb_network_header_len(skb); 518 519 if (!xo || (xo && !(xo->flags & CRYPTO_DONE))) 520 kfree(ESP_SKB_CB(skb)->tmp); 521 522 if (unlikely(err)) 523 goto out; 524 525 err = esp_remove_trailer(skb); 526 if (unlikely(err < 0)) 527 goto out; 528 529 skb_postpull_rcsum(skb, skb_network_header(skb), 530 skb_network_header_len(skb)); 531 skb_pull_rcsum(skb, hlen); 532 if (x->props.mode == XFRM_MODE_TUNNEL) 533 skb_reset_transport_header(skb); 534 else 535 skb_set_transport_header(skb, -hdr_len); 536 537 /* RFC4303: Drop dummy packets without any error */ 538 if (err == IPPROTO_NONE) 539 err = -EINVAL; 540 541 out: 542 return err; 543 } 544 EXPORT_SYMBOL_GPL(esp6_input_done2); 545 546 static void esp_input_done(struct crypto_async_request *base, int err) 547 { 548 struct sk_buff *skb = base->data; 549 550 xfrm_input_resume(skb, esp6_input_done2(skb, err)); 551 } 552 553 static void esp_input_restore_header(struct sk_buff *skb) 554 { 555 esp_restore_header(skb, 0); 556 __skb_pull(skb, 4); 557 } 558 559 static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) 560 { 561 struct xfrm_state *x = xfrm_input_state(skb); 562 563 /* For ESN we move the header forward by 4 bytes to 564 * accomodate the high bits. We will move it back after 565 * decryption. 566 */ 567 if ((x->props.flags & XFRM_STATE_ESN)) { 568 struct ip_esp_hdr *esph = skb_push(skb, 4); 569 570 *seqhi = esph->spi; 571 esph->spi = esph->seq_no; 572 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; 573 } 574 } 575 576 static void esp_input_done_esn(struct crypto_async_request *base, int err) 577 { 578 struct sk_buff *skb = base->data; 579 580 esp_input_restore_header(skb); 581 esp_input_done(base, err); 582 } 583 584 static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) 585 { 586 struct ip_esp_hdr *esph; 587 struct crypto_aead *aead = x->data; 588 struct aead_request *req; 589 struct sk_buff *trailer; 590 int ivlen = crypto_aead_ivsize(aead); 591 int elen = skb->len - sizeof(*esph) - ivlen; 592 int nfrags; 593 int assoclen; 594 int seqhilen; 595 int ret = 0; 596 void *tmp; 597 __be32 *seqhi; 598 u8 *iv; 599 struct scatterlist *sg; 600 601 if (!pskb_may_pull(skb, sizeof(*esph) + ivlen)) { 602 ret = -EINVAL; 603 goto out; 604 } 605 606 if (elen <= 0) { 607 ret = -EINVAL; 608 goto out; 609 } 610 611 assoclen = sizeof(*esph); 612 seqhilen = 0; 613 614 if (x->props.flags & XFRM_STATE_ESN) { 615 seqhilen += sizeof(__be32); 616 assoclen += seqhilen; 617 } 618 619 if (!skb_cloned(skb)) { 620 if (!skb_is_nonlinear(skb)) { 621 nfrags = 1; 622 623 goto skip_cow; 624 } else if (!skb_has_frag_list(skb)) { 625 nfrags = skb_shinfo(skb)->nr_frags; 626 nfrags++; 627 628 goto skip_cow; 629 } 630 } 631 632 nfrags = skb_cow_data(skb, 0, &trailer); 633 if (nfrags < 0) { 634 ret = -EINVAL; 635 goto out; 636 } 637 638 skip_cow: 639 ret = -ENOMEM; 640 tmp = esp_alloc_tmp(aead, nfrags, seqhilen); 641 if (!tmp) 642 goto out; 643 644 ESP_SKB_CB(skb)->tmp = tmp; 645 seqhi = esp_tmp_seqhi(tmp); 646 iv = esp_tmp_iv(aead, tmp, seqhilen); 647 req = esp_tmp_req(aead, iv); 648 sg = esp_req_sg(aead, req); 649 650 esp_input_set_header(skb, seqhi); 651 652 sg_init_table(sg, nfrags); 653 ret = skb_to_sgvec(skb, sg, 0, skb->len); 654 if (unlikely(ret < 0)) 655 goto out; 656 657 skb->ip_summed = CHECKSUM_NONE; 658 659 if ((x->props.flags & XFRM_STATE_ESN)) 660 aead_request_set_callback(req, 0, esp_input_done_esn, skb); 661 else 662 aead_request_set_callback(req, 0, esp_input_done, skb); 663 664 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); 665 aead_request_set_ad(req, assoclen); 666 667 ret = crypto_aead_decrypt(req); 668 if (ret == -EINPROGRESS) 669 goto out; 670 671 if ((x->props.flags & XFRM_STATE_ESN)) 672 esp_input_restore_header(skb); 673 674 ret = esp6_input_done2(skb, ret); 675 676 out: 677 return ret; 678 } 679 680 static u32 esp6_get_mtu(struct xfrm_state *x, int mtu) 681 { 682 struct crypto_aead *aead = x->data; 683 u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); 684 unsigned int net_adj; 685 686 if (x->props.mode != XFRM_MODE_TUNNEL) 687 net_adj = sizeof(struct ipv6hdr); 688 else 689 net_adj = 0; 690 691 return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - 692 net_adj) & ~(blksize - 1)) + net_adj - 2; 693 } 694 695 static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 696 u8 type, u8 code, int offset, __be32 info) 697 { 698 struct net *net = dev_net(skb->dev); 699 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; 700 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); 701 struct xfrm_state *x; 702 703 if (type != ICMPV6_PKT_TOOBIG && 704 type != NDISC_REDIRECT) 705 return 0; 706 707 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, 708 esph->spi, IPPROTO_ESP, AF_INET6); 709 if (!x) 710 return 0; 711 712 if (type == NDISC_REDIRECT) 713 ip6_redirect(skb, net, skb->dev->ifindex, 0, 714 sock_net_uid(net, NULL)); 715 else 716 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); 717 xfrm_state_put(x); 718 719 return 0; 720 } 721 722 static void esp6_destroy(struct xfrm_state *x) 723 { 724 struct crypto_aead *aead = x->data; 725 726 if (!aead) 727 return; 728 729 crypto_free_aead(aead); 730 } 731 732 static int esp_init_aead(struct xfrm_state *x) 733 { 734 char aead_name[CRYPTO_MAX_ALG_NAME]; 735 struct crypto_aead *aead; 736 int err; 737 u32 mask = 0; 738 739 err = -ENAMETOOLONG; 740 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", 741 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) 742 goto error; 743 744 if (x->xso.offload_handle) 745 mask |= CRYPTO_ALG_ASYNC; 746 747 aead = crypto_alloc_aead(aead_name, 0, mask); 748 err = PTR_ERR(aead); 749 if (IS_ERR(aead)) 750 goto error; 751 752 x->data = aead; 753 754 err = crypto_aead_setkey(aead, x->aead->alg_key, 755 (x->aead->alg_key_len + 7) / 8); 756 if (err) 757 goto error; 758 759 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); 760 if (err) 761 goto error; 762 763 error: 764 return err; 765 } 766 767 static int esp_init_authenc(struct xfrm_state *x) 768 { 769 struct crypto_aead *aead; 770 struct crypto_authenc_key_param *param; 771 struct rtattr *rta; 772 char *key; 773 char *p; 774 char authenc_name[CRYPTO_MAX_ALG_NAME]; 775 unsigned int keylen; 776 int err; 777 u32 mask = 0; 778 779 err = -EINVAL; 780 if (!x->ealg) 781 goto error; 782 783 err = -ENAMETOOLONG; 784 785 if ((x->props.flags & XFRM_STATE_ESN)) { 786 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 787 "%s%sauthencesn(%s,%s)%s", 788 x->geniv ?: "", x->geniv ? "(" : "", 789 x->aalg ? x->aalg->alg_name : "digest_null", 790 x->ealg->alg_name, 791 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) 792 goto error; 793 } else { 794 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, 795 "%s%sauthenc(%s,%s)%s", 796 x->geniv ?: "", x->geniv ? "(" : "", 797 x->aalg ? x->aalg->alg_name : "digest_null", 798 x->ealg->alg_name, 799 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) 800 goto error; 801 } 802 803 if (x->xso.offload_handle) 804 mask |= CRYPTO_ALG_ASYNC; 805 806 aead = crypto_alloc_aead(authenc_name, 0, mask); 807 err = PTR_ERR(aead); 808 if (IS_ERR(aead)) 809 goto error; 810 811 x->data = aead; 812 813 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + 814 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); 815 err = -ENOMEM; 816 key = kmalloc(keylen, GFP_KERNEL); 817 if (!key) 818 goto error; 819 820 p = key; 821 rta = (void *)p; 822 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 823 rta->rta_len = RTA_LENGTH(sizeof(*param)); 824 param = RTA_DATA(rta); 825 p += RTA_SPACE(sizeof(*param)); 826 827 if (x->aalg) { 828 struct xfrm_algo_desc *aalg_desc; 829 830 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); 831 p += (x->aalg->alg_key_len + 7) / 8; 832 833 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); 834 BUG_ON(!aalg_desc); 835 836 err = -EINVAL; 837 if (aalg_desc->uinfo.auth.icv_fullbits / 8 != 838 crypto_aead_authsize(aead)) { 839 pr_info("ESP: %s digestsize %u != %hu\n", 840 x->aalg->alg_name, 841 crypto_aead_authsize(aead), 842 aalg_desc->uinfo.auth.icv_fullbits / 8); 843 goto free_key; 844 } 845 846 err = crypto_aead_setauthsize( 847 aead, x->aalg->alg_trunc_len / 8); 848 if (err) 849 goto free_key; 850 } 851 852 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); 853 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); 854 855 err = crypto_aead_setkey(aead, key, keylen); 856 857 free_key: 858 kfree(key); 859 860 error: 861 return err; 862 } 863 864 static int esp6_init_state(struct xfrm_state *x) 865 { 866 struct crypto_aead *aead; 867 u32 align; 868 int err; 869 870 if (x->encap) 871 return -EINVAL; 872 873 x->data = NULL; 874 875 if (x->aead) 876 err = esp_init_aead(x); 877 else 878 err = esp_init_authenc(x); 879 880 if (err) 881 goto error; 882 883 aead = x->data; 884 885 x->props.header_len = sizeof(struct ip_esp_hdr) + 886 crypto_aead_ivsize(aead); 887 switch (x->props.mode) { 888 case XFRM_MODE_BEET: 889 if (x->sel.family != AF_INET6) 890 x->props.header_len += IPV4_BEET_PHMAXLEN + 891 (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); 892 break; 893 case XFRM_MODE_TRANSPORT: 894 break; 895 case XFRM_MODE_TUNNEL: 896 x->props.header_len += sizeof(struct ipv6hdr); 897 break; 898 default: 899 goto error; 900 } 901 902 align = ALIGN(crypto_aead_blocksize(aead), 4); 903 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); 904 905 error: 906 return err; 907 } 908 909 static int esp6_rcv_cb(struct sk_buff *skb, int err) 910 { 911 return 0; 912 } 913 914 static const struct xfrm_type esp6_type = { 915 .description = "ESP6", 916 .owner = THIS_MODULE, 917 .proto = IPPROTO_ESP, 918 .flags = XFRM_TYPE_REPLAY_PROT, 919 .init_state = esp6_init_state, 920 .destructor = esp6_destroy, 921 .get_mtu = esp6_get_mtu, 922 .input = esp6_input, 923 .output = esp6_output, 924 .hdr_offset = xfrm6_find_1stfragopt, 925 }; 926 927 static struct xfrm6_protocol esp6_protocol = { 928 .handler = xfrm6_rcv, 929 .cb_handler = esp6_rcv_cb, 930 .err_handler = esp6_err, 931 .priority = 0, 932 }; 933 934 static int __init esp6_init(void) 935 { 936 if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { 937 pr_info("%s: can't add xfrm type\n", __func__); 938 return -EAGAIN; 939 } 940 if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { 941 pr_info("%s: can't add protocol\n", __func__); 942 xfrm_unregister_type(&esp6_type, AF_INET6); 943 return -EAGAIN; 944 } 945 946 return 0; 947 } 948 949 static void __exit esp6_fini(void) 950 { 951 if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) 952 pr_info("%s: can't remove protocol\n", __func__); 953 if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0) 954 pr_info("%s: can't remove xfrm type\n", __func__); 955 } 956 957 module_init(esp6_init); 958 module_exit(esp6_fini); 959 960 MODULE_LICENSE("GPL"); 961 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP); 962