1 /* 2 * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved. 3 * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved. 4 * Copyright (c) 2016-2017, Lance Chao <lancerchao@fb.com>. All rights reserved. 5 * Copyright (c) 2016, Fridolin Pokorny <fridolin.pokorny@gmail.com>. All rights reserved. 6 * Copyright (c) 2016, Nikos Mavrogiannopoulos <nmav@gnutls.org>. All rights reserved. 7 * 8 * This software is available to you under a choice of one of two 9 * licenses. You may choose to be licensed under the terms of the GNU 10 * General Public License (GPL) Version 2, available from the file 11 * COPYING in the main directory of this source tree, or the 12 * OpenIB.org BSD license below: 13 * 14 * Redistribution and use in source and binary forms, with or 15 * without modification, are permitted provided that the following 16 * conditions are met: 17 * 18 * - Redistributions of source code must retain the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer. 21 * 22 * - Redistributions in binary form must reproduce the above 23 * copyright notice, this list of conditions and the following 24 * disclaimer in the documentation and/or other materials 25 * provided with the distribution. 26 * 27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 28 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 29 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 30 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 31 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 32 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 33 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 34 * SOFTWARE. 35 */ 36 37 #include <linux/sched/signal.h> 38 #include <linux/module.h> 39 #include <crypto/aead.h> 40 41 #include <net/strparser.h> 42 #include <net/tls.h> 43 44 #define MAX_IV_SIZE TLS_CIPHER_AES_GCM_128_IV_SIZE 45 46 static int __skb_nsg(struct sk_buff *skb, int offset, int len, 47 unsigned int recursion_level) 48 { 49 int start = skb_headlen(skb); 50 int i, chunk = start - offset; 51 struct sk_buff *frag_iter; 52 int elt = 0; 53 54 if (unlikely(recursion_level >= 24)) 55 return -EMSGSIZE; 56 57 if (chunk > 0) { 58 if (chunk > len) 59 chunk = len; 60 elt++; 61 len -= chunk; 62 if (len == 0) 63 return elt; 64 offset += chunk; 65 } 66 67 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 68 int end; 69 70 WARN_ON(start > offset + len); 71 72 end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]); 73 chunk = end - offset; 74 if (chunk > 0) { 75 if (chunk > len) 76 chunk = len; 77 elt++; 78 len -= chunk; 79 if (len == 0) 80 return elt; 81 offset += chunk; 82 } 83 start = end; 84 } 85 86 if (unlikely(skb_has_frag_list(skb))) { 87 skb_walk_frags(skb, frag_iter) { 88 int end, ret; 89 90 WARN_ON(start > offset + len); 91 92 end = start + frag_iter->len; 93 chunk = end - offset; 94 if (chunk > 0) { 95 if (chunk > len) 96 chunk = len; 97 ret = __skb_nsg(frag_iter, offset - start, chunk, 98 recursion_level + 1); 99 if (unlikely(ret < 0)) 100 return ret; 101 elt += ret; 102 len -= chunk; 103 if (len == 0) 104 return elt; 105 offset += chunk; 106 } 107 start = end; 108 } 109 } 110 BUG_ON(len); 111 return elt; 112 } 113 114 /* Return the number of scatterlist elements required to completely map the 115 * skb, or -EMSGSIZE if the recursion depth is exceeded. 116 */ 117 static int skb_nsg(struct sk_buff *skb, int offset, int len) 118 { 119 return __skb_nsg(skb, offset, len, 0); 120 } 121 122 static void tls_decrypt_done(struct crypto_async_request *req, int err) 123 { 124 struct aead_request *aead_req = (struct aead_request *)req; 125 struct scatterlist *sgout = aead_req->dst; 126 struct tls_sw_context_rx *ctx; 127 struct tls_context *tls_ctx; 128 struct scatterlist *sg; 129 struct sk_buff *skb; 130 unsigned int pages; 131 int pending; 132 133 skb = (struct sk_buff *)req->data; 134 tls_ctx = tls_get_ctx(skb->sk); 135 ctx = tls_sw_ctx_rx(tls_ctx); 136 pending = atomic_dec_return(&ctx->decrypt_pending); 137 138 /* Propagate if there was an err */ 139 if (err) { 140 ctx->async_wait.err = err; 141 tls_err_abort(skb->sk, err); 142 } 143 144 /* After using skb->sk to propagate sk through crypto async callback 145 * we need to NULL it again. 146 */ 147 skb->sk = NULL; 148 149 /* Release the skb, pages and memory allocated for crypto req */ 150 kfree_skb(skb); 151 152 /* Skip the first S/G entry as it points to AAD */ 153 for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) { 154 if (!sg) 155 break; 156 put_page(sg_page(sg)); 157 } 158 159 kfree(aead_req); 160 161 if (!pending && READ_ONCE(ctx->async_notify)) 162 complete(&ctx->async_wait.completion); 163 } 164 165 static int tls_do_decryption(struct sock *sk, 166 struct sk_buff *skb, 167 struct scatterlist *sgin, 168 struct scatterlist *sgout, 169 char *iv_recv, 170 size_t data_len, 171 struct aead_request *aead_req, 172 bool async) 173 { 174 struct tls_context *tls_ctx = tls_get_ctx(sk); 175 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 176 int ret; 177 178 aead_request_set_tfm(aead_req, ctx->aead_recv); 179 aead_request_set_ad(aead_req, TLS_AAD_SPACE_SIZE); 180 aead_request_set_crypt(aead_req, sgin, sgout, 181 data_len + tls_ctx->rx.tag_size, 182 (u8 *)iv_recv); 183 184 if (async) { 185 /* Using skb->sk to push sk through to crypto async callback 186 * handler. This allows propagating errors up to the socket 187 * if needed. It _must_ be cleared in the async handler 188 * before kfree_skb is called. We _know_ skb->sk is NULL 189 * because it is a clone from strparser. 190 */ 191 skb->sk = sk; 192 aead_request_set_callback(aead_req, 193 CRYPTO_TFM_REQ_MAY_BACKLOG, 194 tls_decrypt_done, skb); 195 atomic_inc(&ctx->decrypt_pending); 196 } else { 197 aead_request_set_callback(aead_req, 198 CRYPTO_TFM_REQ_MAY_BACKLOG, 199 crypto_req_done, &ctx->async_wait); 200 } 201 202 ret = crypto_aead_decrypt(aead_req); 203 if (ret == -EINPROGRESS) { 204 if (async) 205 return ret; 206 207 ret = crypto_wait_req(ret, &ctx->async_wait); 208 } 209 210 if (async) 211 atomic_dec(&ctx->decrypt_pending); 212 213 return ret; 214 } 215 216 static void trim_sg(struct sock *sk, struct scatterlist *sg, 217 int *sg_num_elem, unsigned int *sg_size, int target_size) 218 { 219 int i = *sg_num_elem - 1; 220 int trim = *sg_size - target_size; 221 222 if (trim <= 0) { 223 WARN_ON(trim < 0); 224 return; 225 } 226 227 *sg_size = target_size; 228 while (trim >= sg[i].length) { 229 trim -= sg[i].length; 230 sk_mem_uncharge(sk, sg[i].length); 231 put_page(sg_page(&sg[i])); 232 i--; 233 234 if (i < 0) 235 goto out; 236 } 237 238 sg[i].length -= trim; 239 sk_mem_uncharge(sk, trim); 240 241 out: 242 *sg_num_elem = i + 1; 243 } 244 245 static void trim_both_sgl(struct sock *sk, int target_size) 246 { 247 struct tls_context *tls_ctx = tls_get_ctx(sk); 248 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 249 struct tls_rec *rec = ctx->open_rec; 250 251 trim_sg(sk, &rec->sg_plaintext_data[1], 252 &rec->sg_plaintext_num_elem, 253 &rec->sg_plaintext_size, 254 target_size); 255 256 if (target_size > 0) 257 target_size += tls_ctx->tx.overhead_size; 258 259 trim_sg(sk, &rec->sg_encrypted_data[1], 260 &rec->sg_encrypted_num_elem, 261 &rec->sg_encrypted_size, 262 target_size); 263 } 264 265 static int alloc_encrypted_sg(struct sock *sk, int len) 266 { 267 struct tls_context *tls_ctx = tls_get_ctx(sk); 268 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 269 struct tls_rec *rec = ctx->open_rec; 270 int rc = 0; 271 272 rc = sk_alloc_sg(sk, len, 273 &rec->sg_encrypted_data[1], 0, 274 &rec->sg_encrypted_num_elem, 275 &rec->sg_encrypted_size, 0); 276 277 if (rc == -ENOSPC) 278 rec->sg_encrypted_num_elem = 279 ARRAY_SIZE(rec->sg_encrypted_data) - 1; 280 281 return rc; 282 } 283 284 static int move_to_plaintext_sg(struct sock *sk, int required_size) 285 { 286 struct tls_context *tls_ctx = tls_get_ctx(sk); 287 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 288 struct tls_rec *rec = ctx->open_rec; 289 struct scatterlist *plain_sg = &rec->sg_plaintext_data[1]; 290 struct scatterlist *enc_sg = &rec->sg_encrypted_data[1]; 291 int enc_sg_idx = 0; 292 int skip, len; 293 294 if (rec->sg_plaintext_num_elem == MAX_SKB_FRAGS) 295 return -ENOSPC; 296 297 /* We add page references worth len bytes from enc_sg at the 298 * end of plain_sg. It is guaranteed that sg_encrypted_data 299 * has enough required room (ensured by caller). 300 */ 301 len = required_size - rec->sg_plaintext_size; 302 303 /* Skip initial bytes in sg_encrypted_data to be able 304 * to use same offset of both plain and encrypted data. 305 */ 306 skip = tls_ctx->tx.prepend_size + rec->sg_plaintext_size; 307 308 while (enc_sg_idx < rec->sg_encrypted_num_elem) { 309 if (enc_sg[enc_sg_idx].length > skip) 310 break; 311 312 skip -= enc_sg[enc_sg_idx].length; 313 enc_sg_idx++; 314 } 315 316 /* unmark the end of plain_sg*/ 317 sg_unmark_end(plain_sg + rec->sg_plaintext_num_elem - 1); 318 319 while (len) { 320 struct page *page = sg_page(&enc_sg[enc_sg_idx]); 321 int bytes = enc_sg[enc_sg_idx].length - skip; 322 int offset = enc_sg[enc_sg_idx].offset + skip; 323 324 if (bytes > len) 325 bytes = len; 326 else 327 enc_sg_idx++; 328 329 /* Skipping is required only one time */ 330 skip = 0; 331 332 /* Increment page reference */ 333 get_page(page); 334 335 sg_set_page(&plain_sg[rec->sg_plaintext_num_elem], page, 336 bytes, offset); 337 338 sk_mem_charge(sk, bytes); 339 340 len -= bytes; 341 rec->sg_plaintext_size += bytes; 342 343 rec->sg_plaintext_num_elem++; 344 345 if (rec->sg_plaintext_num_elem == MAX_SKB_FRAGS) 346 return -ENOSPC; 347 } 348 349 return 0; 350 } 351 352 static void free_sg(struct sock *sk, struct scatterlist *sg, 353 int *sg_num_elem, unsigned int *sg_size) 354 { 355 int i, n = *sg_num_elem; 356 357 for (i = 0; i < n; ++i) { 358 sk_mem_uncharge(sk, sg[i].length); 359 put_page(sg_page(&sg[i])); 360 } 361 *sg_num_elem = 0; 362 *sg_size = 0; 363 } 364 365 static void tls_free_open_rec(struct sock *sk) 366 { 367 struct tls_context *tls_ctx = tls_get_ctx(sk); 368 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 369 struct tls_rec *rec = ctx->open_rec; 370 371 /* Return if there is no open record */ 372 if (!rec) 373 return; 374 375 free_sg(sk, &rec->sg_encrypted_data[1], 376 &rec->sg_encrypted_num_elem, 377 &rec->sg_encrypted_size); 378 379 free_sg(sk, &rec->sg_plaintext_data[1], 380 &rec->sg_plaintext_num_elem, 381 &rec->sg_plaintext_size); 382 383 kfree(rec); 384 } 385 386 int tls_tx_records(struct sock *sk, int flags) 387 { 388 struct tls_context *tls_ctx = tls_get_ctx(sk); 389 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 390 struct tls_rec *rec, *tmp; 391 int tx_flags, rc = 0; 392 393 if (tls_is_partially_sent_record(tls_ctx)) { 394 rec = list_first_entry(&ctx->tx_list, 395 struct tls_rec, list); 396 397 if (flags == -1) 398 tx_flags = rec->tx_flags; 399 else 400 tx_flags = flags; 401 402 rc = tls_push_partial_record(sk, tls_ctx, tx_flags); 403 if (rc) 404 goto tx_err; 405 406 /* Full record has been transmitted. 407 * Remove the head of tx_list 408 */ 409 list_del(&rec->list); 410 free_sg(sk, &rec->sg_plaintext_data[1], 411 &rec->sg_plaintext_num_elem, &rec->sg_plaintext_size); 412 413 kfree(rec); 414 } 415 416 /* Tx all ready records */ 417 list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) { 418 if (READ_ONCE(rec->tx_ready)) { 419 if (flags == -1) 420 tx_flags = rec->tx_flags; 421 else 422 tx_flags = flags; 423 424 rc = tls_push_sg(sk, tls_ctx, 425 &rec->sg_encrypted_data[1], 426 0, tx_flags); 427 if (rc) 428 goto tx_err; 429 430 list_del(&rec->list); 431 free_sg(sk, &rec->sg_plaintext_data[1], 432 &rec->sg_plaintext_num_elem, 433 &rec->sg_plaintext_size); 434 435 kfree(rec); 436 } else { 437 break; 438 } 439 } 440 441 tx_err: 442 if (rc < 0 && rc != -EAGAIN) 443 tls_err_abort(sk, EBADMSG); 444 445 return rc; 446 } 447 448 static void tls_encrypt_done(struct crypto_async_request *req, int err) 449 { 450 struct aead_request *aead_req = (struct aead_request *)req; 451 struct sock *sk = req->data; 452 struct tls_context *tls_ctx = tls_get_ctx(sk); 453 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 454 struct tls_rec *rec; 455 bool ready = false; 456 int pending; 457 458 rec = container_of(aead_req, struct tls_rec, aead_req); 459 460 rec->sg_encrypted_data[1].offset -= tls_ctx->tx.prepend_size; 461 rec->sg_encrypted_data[1].length += tls_ctx->tx.prepend_size; 462 463 464 /* Check if error is previously set on socket */ 465 if (err || sk->sk_err) { 466 rec = NULL; 467 468 /* If err is already set on socket, return the same code */ 469 if (sk->sk_err) { 470 ctx->async_wait.err = sk->sk_err; 471 } else { 472 ctx->async_wait.err = err; 473 tls_err_abort(sk, err); 474 } 475 } 476 477 if (rec) { 478 struct tls_rec *first_rec; 479 480 /* Mark the record as ready for transmission */ 481 smp_store_mb(rec->tx_ready, true); 482 483 /* If received record is at head of tx_list, schedule tx */ 484 first_rec = list_first_entry(&ctx->tx_list, 485 struct tls_rec, list); 486 if (rec == first_rec) 487 ready = true; 488 } 489 490 pending = atomic_dec_return(&ctx->encrypt_pending); 491 492 if (!pending && READ_ONCE(ctx->async_notify)) 493 complete(&ctx->async_wait.completion); 494 495 if (!ready) 496 return; 497 498 /* Schedule the transmission */ 499 if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) 500 schedule_delayed_work(&ctx->tx_work.work, 2); 501 } 502 503 static int tls_do_encryption(struct sock *sk, 504 struct tls_context *tls_ctx, 505 struct tls_sw_context_tx *ctx, 506 struct aead_request *aead_req, 507 size_t data_len) 508 { 509 struct tls_rec *rec = ctx->open_rec; 510 struct scatterlist *plain_sg = rec->sg_plaintext_data; 511 struct scatterlist *enc_sg = rec->sg_encrypted_data; 512 int rc; 513 514 /* Skip the first index as it contains AAD data */ 515 rec->sg_encrypted_data[1].offset += tls_ctx->tx.prepend_size; 516 rec->sg_encrypted_data[1].length -= tls_ctx->tx.prepend_size; 517 518 /* If it is inplace crypto, then pass same SG list as both src, dst */ 519 if (rec->inplace_crypto) 520 plain_sg = enc_sg; 521 522 aead_request_set_tfm(aead_req, ctx->aead_send); 523 aead_request_set_ad(aead_req, TLS_AAD_SPACE_SIZE); 524 aead_request_set_crypt(aead_req, plain_sg, enc_sg, 525 data_len, tls_ctx->tx.iv); 526 527 aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG, 528 tls_encrypt_done, sk); 529 530 /* Add the record in tx_list */ 531 list_add_tail((struct list_head *)&rec->list, &ctx->tx_list); 532 atomic_inc(&ctx->encrypt_pending); 533 534 rc = crypto_aead_encrypt(aead_req); 535 if (!rc || rc != -EINPROGRESS) { 536 atomic_dec(&ctx->encrypt_pending); 537 rec->sg_encrypted_data[1].offset -= tls_ctx->tx.prepend_size; 538 rec->sg_encrypted_data[1].length += tls_ctx->tx.prepend_size; 539 } 540 541 if (!rc) { 542 WRITE_ONCE(rec->tx_ready, true); 543 } else if (rc != -EINPROGRESS) { 544 list_del(&rec->list); 545 return rc; 546 } 547 548 /* Unhook the record from context if encryption is not failure */ 549 ctx->open_rec = NULL; 550 tls_advance_record_sn(sk, &tls_ctx->tx); 551 return rc; 552 } 553 554 static int tls_push_record(struct sock *sk, int flags, 555 unsigned char record_type) 556 { 557 struct tls_context *tls_ctx = tls_get_ctx(sk); 558 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 559 struct tls_rec *rec = ctx->open_rec; 560 struct aead_request *req; 561 int rc; 562 563 if (!rec) 564 return 0; 565 566 rec->tx_flags = flags; 567 req = &rec->aead_req; 568 569 sg_mark_end(rec->sg_plaintext_data + rec->sg_plaintext_num_elem); 570 sg_mark_end(rec->sg_encrypted_data + rec->sg_encrypted_num_elem); 571 572 tls_make_aad(rec->aad_space, rec->sg_plaintext_size, 573 tls_ctx->tx.rec_seq, tls_ctx->tx.rec_seq_size, 574 record_type); 575 576 tls_fill_prepend(tls_ctx, 577 page_address(sg_page(&rec->sg_encrypted_data[1])) + 578 rec->sg_encrypted_data[1].offset, 579 rec->sg_plaintext_size, record_type); 580 581 tls_ctx->pending_open_record_frags = 0; 582 583 rc = tls_do_encryption(sk, tls_ctx, ctx, req, rec->sg_plaintext_size); 584 if (rc == -EINPROGRESS) 585 return -EINPROGRESS; 586 587 if (rc < 0) { 588 tls_err_abort(sk, EBADMSG); 589 return rc; 590 } 591 592 return tls_tx_records(sk, flags); 593 } 594 595 static int tls_sw_push_pending_record(struct sock *sk, int flags) 596 { 597 return tls_push_record(sk, flags, TLS_RECORD_TYPE_DATA); 598 } 599 600 static int zerocopy_from_iter(struct sock *sk, struct iov_iter *from, 601 int length, int *pages_used, 602 unsigned int *size_used, 603 struct scatterlist *to, int to_max_pages, 604 bool charge) 605 { 606 struct page *pages[MAX_SKB_FRAGS]; 607 608 size_t offset; 609 ssize_t copied, use; 610 int i = 0; 611 unsigned int size = *size_used; 612 int num_elem = *pages_used; 613 int rc = 0; 614 int maxpages; 615 616 while (length > 0) { 617 i = 0; 618 maxpages = to_max_pages - num_elem; 619 if (maxpages == 0) { 620 rc = -EFAULT; 621 goto out; 622 } 623 copied = iov_iter_get_pages(from, pages, 624 length, 625 maxpages, &offset); 626 if (copied <= 0) { 627 rc = -EFAULT; 628 goto out; 629 } 630 631 iov_iter_advance(from, copied); 632 633 length -= copied; 634 size += copied; 635 while (copied) { 636 use = min_t(int, copied, PAGE_SIZE - offset); 637 638 sg_set_page(&to[num_elem], 639 pages[i], use, offset); 640 sg_unmark_end(&to[num_elem]); 641 if (charge) 642 sk_mem_charge(sk, use); 643 644 offset = 0; 645 copied -= use; 646 647 ++i; 648 ++num_elem; 649 } 650 } 651 652 /* Mark the end in the last sg entry if newly added */ 653 if (num_elem > *pages_used) 654 sg_mark_end(&to[num_elem - 1]); 655 out: 656 if (rc) 657 iov_iter_revert(from, size - *size_used); 658 *size_used = size; 659 *pages_used = num_elem; 660 661 return rc; 662 } 663 664 static int memcopy_from_iter(struct sock *sk, struct iov_iter *from, 665 int bytes) 666 { 667 struct tls_context *tls_ctx = tls_get_ctx(sk); 668 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 669 struct tls_rec *rec = ctx->open_rec; 670 struct scatterlist *sg = &rec->sg_plaintext_data[1]; 671 int copy, i, rc = 0; 672 673 for (i = tls_ctx->pending_open_record_frags; 674 i < rec->sg_plaintext_num_elem; ++i) { 675 copy = sg[i].length; 676 if (copy_from_iter( 677 page_address(sg_page(&sg[i])) + sg[i].offset, 678 copy, from) != copy) { 679 rc = -EFAULT; 680 goto out; 681 } 682 bytes -= copy; 683 684 ++tls_ctx->pending_open_record_frags; 685 686 if (!bytes) 687 break; 688 } 689 690 out: 691 return rc; 692 } 693 694 static struct tls_rec *get_rec(struct sock *sk) 695 { 696 struct tls_context *tls_ctx = tls_get_ctx(sk); 697 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 698 struct tls_rec *rec; 699 int mem_size; 700 701 /* Return if we already have an open record */ 702 if (ctx->open_rec) 703 return ctx->open_rec; 704 705 mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send); 706 707 rec = kzalloc(mem_size, sk->sk_allocation); 708 if (!rec) 709 return NULL; 710 711 sg_init_table(&rec->sg_plaintext_data[0], 712 ARRAY_SIZE(rec->sg_plaintext_data)); 713 sg_init_table(&rec->sg_encrypted_data[0], 714 ARRAY_SIZE(rec->sg_encrypted_data)); 715 716 sg_set_buf(&rec->sg_plaintext_data[0], rec->aad_space, 717 sizeof(rec->aad_space)); 718 sg_set_buf(&rec->sg_encrypted_data[0], rec->aad_space, 719 sizeof(rec->aad_space)); 720 721 ctx->open_rec = rec; 722 rec->inplace_crypto = 1; 723 724 return rec; 725 } 726 727 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) 728 { 729 long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 730 struct tls_context *tls_ctx = tls_get_ctx(sk); 731 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 732 struct crypto_tfm *tfm = crypto_aead_tfm(ctx->aead_send); 733 bool async_capable = tfm->__crt_alg->cra_flags & CRYPTO_ALG_ASYNC; 734 unsigned char record_type = TLS_RECORD_TYPE_DATA; 735 bool is_kvec = msg->msg_iter.type & ITER_KVEC; 736 bool eor = !(msg->msg_flags & MSG_MORE); 737 size_t try_to_copy, copied = 0; 738 struct tls_rec *rec; 739 int required_size; 740 int num_async = 0; 741 bool full_record; 742 int record_room; 743 int num_zc = 0; 744 int orig_size; 745 int ret = 0; 746 747 if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL)) 748 return -ENOTSUPP; 749 750 lock_sock(sk); 751 752 /* Wait till there is any pending write on socket */ 753 if (unlikely(sk->sk_write_pending)) { 754 ret = wait_on_pending_writer(sk, &timeo); 755 if (unlikely(ret)) 756 goto send_end; 757 } 758 759 if (unlikely(msg->msg_controllen)) { 760 ret = tls_proccess_cmsg(sk, msg, &record_type); 761 if (ret) { 762 if (ret == -EINPROGRESS) 763 num_async++; 764 else if (ret != -EAGAIN) 765 goto send_end; 766 } 767 } 768 769 while (msg_data_left(msg)) { 770 if (sk->sk_err) { 771 ret = -sk->sk_err; 772 goto send_end; 773 } 774 775 rec = get_rec(sk); 776 if (!rec) { 777 ret = -ENOMEM; 778 goto send_end; 779 } 780 781 orig_size = rec->sg_plaintext_size; 782 full_record = false; 783 try_to_copy = msg_data_left(msg); 784 record_room = TLS_MAX_PAYLOAD_SIZE - rec->sg_plaintext_size; 785 if (try_to_copy >= record_room) { 786 try_to_copy = record_room; 787 full_record = true; 788 } 789 790 required_size = rec->sg_plaintext_size + try_to_copy + 791 tls_ctx->tx.overhead_size; 792 793 if (!sk_stream_memory_free(sk)) 794 goto wait_for_sndbuf; 795 796 alloc_encrypted: 797 ret = alloc_encrypted_sg(sk, required_size); 798 if (ret) { 799 if (ret != -ENOSPC) 800 goto wait_for_memory; 801 802 /* Adjust try_to_copy according to the amount that was 803 * actually allocated. The difference is due 804 * to max sg elements limit 805 */ 806 try_to_copy -= required_size - rec->sg_encrypted_size; 807 full_record = true; 808 } 809 810 if (!is_kvec && (full_record || eor) && !async_capable) { 811 ret = zerocopy_from_iter(sk, &msg->msg_iter, 812 try_to_copy, &rec->sg_plaintext_num_elem, 813 &rec->sg_plaintext_size, 814 &rec->sg_plaintext_data[1], 815 ARRAY_SIZE(rec->sg_plaintext_data) - 1, 816 true); 817 if (ret) 818 goto fallback_to_reg_send; 819 820 rec->inplace_crypto = 0; 821 822 num_zc++; 823 copied += try_to_copy; 824 ret = tls_push_record(sk, msg->msg_flags, record_type); 825 if (ret) { 826 if (ret == -EINPROGRESS) 827 num_async++; 828 else if (ret != -EAGAIN) 829 goto send_end; 830 } 831 continue; 832 833 fallback_to_reg_send: 834 trim_sg(sk, &rec->sg_plaintext_data[1], 835 &rec->sg_plaintext_num_elem, 836 &rec->sg_plaintext_size, 837 orig_size); 838 } 839 840 required_size = rec->sg_plaintext_size + try_to_copy; 841 842 ret = move_to_plaintext_sg(sk, required_size); 843 if (ret) { 844 if (ret != -ENOSPC) 845 goto send_end; 846 847 /* Adjust try_to_copy according to the amount that was 848 * actually allocated. The difference is due 849 * to max sg elements limit 850 */ 851 try_to_copy -= required_size - rec->sg_plaintext_size; 852 full_record = true; 853 854 trim_sg(sk, &rec->sg_encrypted_data[1], 855 &rec->sg_encrypted_num_elem, 856 &rec->sg_encrypted_size, 857 rec->sg_plaintext_size + 858 tls_ctx->tx.overhead_size); 859 } 860 861 ret = memcopy_from_iter(sk, &msg->msg_iter, try_to_copy); 862 if (ret) 863 goto trim_sgl; 864 865 copied += try_to_copy; 866 if (full_record || eor) { 867 ret = tls_push_record(sk, msg->msg_flags, record_type); 868 if (ret) { 869 if (ret == -EINPROGRESS) 870 num_async++; 871 else if (ret != -EAGAIN) 872 goto send_end; 873 } 874 } 875 876 continue; 877 878 wait_for_sndbuf: 879 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 880 wait_for_memory: 881 ret = sk_stream_wait_memory(sk, &timeo); 882 if (ret) { 883 trim_sgl: 884 trim_both_sgl(sk, orig_size); 885 goto send_end; 886 } 887 888 if (rec->sg_encrypted_size < required_size) 889 goto alloc_encrypted; 890 } 891 892 if (!num_async) { 893 goto send_end; 894 } else if (num_zc) { 895 /* Wait for pending encryptions to get completed */ 896 smp_store_mb(ctx->async_notify, true); 897 898 if (atomic_read(&ctx->encrypt_pending)) 899 crypto_wait_req(-EINPROGRESS, &ctx->async_wait); 900 else 901 reinit_completion(&ctx->async_wait.completion); 902 903 WRITE_ONCE(ctx->async_notify, false); 904 905 if (ctx->async_wait.err) { 906 ret = ctx->async_wait.err; 907 copied = 0; 908 } 909 } 910 911 /* Transmit if any encryptions have completed */ 912 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { 913 cancel_delayed_work(&ctx->tx_work.work); 914 tls_tx_records(sk, msg->msg_flags); 915 } 916 917 send_end: 918 ret = sk_stream_error(sk, msg->msg_flags, ret); 919 920 release_sock(sk); 921 return copied ? copied : ret; 922 } 923 924 int tls_sw_sendpage(struct sock *sk, struct page *page, 925 int offset, size_t size, int flags) 926 { 927 long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); 928 struct tls_context *tls_ctx = tls_get_ctx(sk); 929 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 930 unsigned char record_type = TLS_RECORD_TYPE_DATA; 931 size_t orig_size = size; 932 struct scatterlist *sg; 933 struct tls_rec *rec; 934 int num_async = 0; 935 bool full_record; 936 int record_room; 937 int ret = 0; 938 bool eor; 939 940 if (flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | 941 MSG_SENDPAGE_NOTLAST)) 942 return -ENOTSUPP; 943 944 /* No MSG_EOR from splice, only look at MSG_MORE */ 945 eor = !(flags & (MSG_MORE | MSG_SENDPAGE_NOTLAST)); 946 947 lock_sock(sk); 948 949 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); 950 951 /* Wait till there is any pending write on socket */ 952 if (unlikely(sk->sk_write_pending)) { 953 ret = wait_on_pending_writer(sk, &timeo); 954 if (unlikely(ret)) 955 goto sendpage_end; 956 } 957 958 /* Call the sk_stream functions to manage the sndbuf mem. */ 959 while (size > 0) { 960 size_t copy, required_size; 961 962 if (sk->sk_err) { 963 ret = -sk->sk_err; 964 goto sendpage_end; 965 } 966 967 rec = get_rec(sk); 968 if (!rec) { 969 ret = -ENOMEM; 970 goto sendpage_end; 971 } 972 973 full_record = false; 974 record_room = TLS_MAX_PAYLOAD_SIZE - rec->sg_plaintext_size; 975 copy = size; 976 if (copy >= record_room) { 977 copy = record_room; 978 full_record = true; 979 } 980 required_size = rec->sg_plaintext_size + copy + 981 tls_ctx->tx.overhead_size; 982 983 if (!sk_stream_memory_free(sk)) 984 goto wait_for_sndbuf; 985 alloc_payload: 986 ret = alloc_encrypted_sg(sk, required_size); 987 if (ret) { 988 if (ret != -ENOSPC) 989 goto wait_for_memory; 990 991 /* Adjust copy according to the amount that was 992 * actually allocated. The difference is due 993 * to max sg elements limit 994 */ 995 copy -= required_size - rec->sg_plaintext_size; 996 full_record = true; 997 } 998 999 get_page(page); 1000 sg = &rec->sg_plaintext_data[1] + rec->sg_plaintext_num_elem; 1001 sg_set_page(sg, page, copy, offset); 1002 sg_unmark_end(sg); 1003 1004 rec->sg_plaintext_num_elem++; 1005 1006 sk_mem_charge(sk, copy); 1007 offset += copy; 1008 size -= copy; 1009 rec->sg_plaintext_size += copy; 1010 tls_ctx->pending_open_record_frags = rec->sg_plaintext_num_elem; 1011 1012 if (full_record || eor || 1013 rec->sg_plaintext_num_elem == 1014 ARRAY_SIZE(rec->sg_plaintext_data) - 1) { 1015 rec->inplace_crypto = 0; 1016 ret = tls_push_record(sk, flags, record_type); 1017 if (ret) { 1018 if (ret == -EINPROGRESS) 1019 num_async++; 1020 else if (ret != -EAGAIN) 1021 goto sendpage_end; 1022 } 1023 } 1024 continue; 1025 wait_for_sndbuf: 1026 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1027 wait_for_memory: 1028 ret = sk_stream_wait_memory(sk, &timeo); 1029 if (ret) { 1030 trim_both_sgl(sk, rec->sg_plaintext_size); 1031 goto sendpage_end; 1032 } 1033 1034 goto alloc_payload; 1035 } 1036 1037 if (num_async) { 1038 /* Transmit if any encryptions have completed */ 1039 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { 1040 cancel_delayed_work(&ctx->tx_work.work); 1041 tls_tx_records(sk, flags); 1042 } 1043 } 1044 sendpage_end: 1045 if (orig_size > size) 1046 ret = orig_size - size; 1047 else 1048 ret = sk_stream_error(sk, flags, ret); 1049 1050 release_sock(sk); 1051 return ret; 1052 } 1053 1054 static struct sk_buff *tls_wait_data(struct sock *sk, int flags, 1055 long timeo, int *err) 1056 { 1057 struct tls_context *tls_ctx = tls_get_ctx(sk); 1058 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1059 struct sk_buff *skb; 1060 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1061 1062 while (!(skb = ctx->recv_pkt)) { 1063 if (sk->sk_err) { 1064 *err = sock_error(sk); 1065 return NULL; 1066 } 1067 1068 if (sk->sk_shutdown & RCV_SHUTDOWN) 1069 return NULL; 1070 1071 if (sock_flag(sk, SOCK_DONE)) 1072 return NULL; 1073 1074 if ((flags & MSG_DONTWAIT) || !timeo) { 1075 *err = -EAGAIN; 1076 return NULL; 1077 } 1078 1079 add_wait_queue(sk_sleep(sk), &wait); 1080 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 1081 sk_wait_event(sk, &timeo, ctx->recv_pkt != skb, &wait); 1082 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 1083 remove_wait_queue(sk_sleep(sk), &wait); 1084 1085 /* Handle signals */ 1086 if (signal_pending(current)) { 1087 *err = sock_intr_errno(timeo); 1088 return NULL; 1089 } 1090 } 1091 1092 return skb; 1093 } 1094 1095 /* This function decrypts the input skb into either out_iov or in out_sg 1096 * or in skb buffers itself. The input parameter 'zc' indicates if 1097 * zero-copy mode needs to be tried or not. With zero-copy mode, either 1098 * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are 1099 * NULL, then the decryption happens inside skb buffers itself, i.e. 1100 * zero-copy gets disabled and 'zc' is updated. 1101 */ 1102 1103 static int decrypt_internal(struct sock *sk, struct sk_buff *skb, 1104 struct iov_iter *out_iov, 1105 struct scatterlist *out_sg, 1106 int *chunk, bool *zc) 1107 { 1108 struct tls_context *tls_ctx = tls_get_ctx(sk); 1109 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1110 struct strp_msg *rxm = strp_msg(skb); 1111 int n_sgin, n_sgout, nsg, mem_size, aead_size, err, pages = 0; 1112 struct aead_request *aead_req; 1113 struct sk_buff *unused; 1114 u8 *aad, *iv, *mem = NULL; 1115 struct scatterlist *sgin = NULL; 1116 struct scatterlist *sgout = NULL; 1117 const int data_len = rxm->full_len - tls_ctx->rx.overhead_size; 1118 1119 if (*zc && (out_iov || out_sg)) { 1120 if (out_iov) 1121 n_sgout = iov_iter_npages(out_iov, INT_MAX) + 1; 1122 else 1123 n_sgout = sg_nents(out_sg); 1124 n_sgin = skb_nsg(skb, rxm->offset + tls_ctx->rx.prepend_size, 1125 rxm->full_len - tls_ctx->rx.prepend_size); 1126 } else { 1127 n_sgout = 0; 1128 *zc = false; 1129 n_sgin = skb_cow_data(skb, 0, &unused); 1130 } 1131 1132 if (n_sgin < 1) 1133 return -EBADMSG; 1134 1135 /* Increment to accommodate AAD */ 1136 n_sgin = n_sgin + 1; 1137 1138 nsg = n_sgin + n_sgout; 1139 1140 aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv); 1141 mem_size = aead_size + (nsg * sizeof(struct scatterlist)); 1142 mem_size = mem_size + TLS_AAD_SPACE_SIZE; 1143 mem_size = mem_size + crypto_aead_ivsize(ctx->aead_recv); 1144 1145 /* Allocate a single block of memory which contains 1146 * aead_req || sgin[] || sgout[] || aad || iv. 1147 * This order achieves correct alignment for aead_req, sgin, sgout. 1148 */ 1149 mem = kmalloc(mem_size, sk->sk_allocation); 1150 if (!mem) 1151 return -ENOMEM; 1152 1153 /* Segment the allocated memory */ 1154 aead_req = (struct aead_request *)mem; 1155 sgin = (struct scatterlist *)(mem + aead_size); 1156 sgout = sgin + n_sgin; 1157 aad = (u8 *)(sgout + n_sgout); 1158 iv = aad + TLS_AAD_SPACE_SIZE; 1159 1160 /* Prepare IV */ 1161 err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE, 1162 iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 1163 tls_ctx->rx.iv_size); 1164 if (err < 0) { 1165 kfree(mem); 1166 return err; 1167 } 1168 memcpy(iv, tls_ctx->rx.iv, TLS_CIPHER_AES_GCM_128_SALT_SIZE); 1169 1170 /* Prepare AAD */ 1171 tls_make_aad(aad, rxm->full_len - tls_ctx->rx.overhead_size, 1172 tls_ctx->rx.rec_seq, tls_ctx->rx.rec_seq_size, 1173 ctx->control); 1174 1175 /* Prepare sgin */ 1176 sg_init_table(sgin, n_sgin); 1177 sg_set_buf(&sgin[0], aad, TLS_AAD_SPACE_SIZE); 1178 err = skb_to_sgvec(skb, &sgin[1], 1179 rxm->offset + tls_ctx->rx.prepend_size, 1180 rxm->full_len - tls_ctx->rx.prepend_size); 1181 if (err < 0) { 1182 kfree(mem); 1183 return err; 1184 } 1185 1186 if (n_sgout) { 1187 if (out_iov) { 1188 sg_init_table(sgout, n_sgout); 1189 sg_set_buf(&sgout[0], aad, TLS_AAD_SPACE_SIZE); 1190 1191 *chunk = 0; 1192 err = zerocopy_from_iter(sk, out_iov, data_len, &pages, 1193 chunk, &sgout[1], 1194 (n_sgout - 1), false); 1195 if (err < 0) 1196 goto fallback_to_reg_recv; 1197 } else if (out_sg) { 1198 memcpy(sgout, out_sg, n_sgout * sizeof(*sgout)); 1199 } else { 1200 goto fallback_to_reg_recv; 1201 } 1202 } else { 1203 fallback_to_reg_recv: 1204 sgout = sgin; 1205 pages = 0; 1206 *chunk = 0; 1207 *zc = false; 1208 } 1209 1210 /* Prepare and submit AEAD request */ 1211 err = tls_do_decryption(sk, skb, sgin, sgout, iv, 1212 data_len, aead_req, *zc); 1213 if (err == -EINPROGRESS) 1214 return err; 1215 1216 /* Release the pages in case iov was mapped to pages */ 1217 for (; pages > 0; pages--) 1218 put_page(sg_page(&sgout[pages])); 1219 1220 kfree(mem); 1221 return err; 1222 } 1223 1224 static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb, 1225 struct iov_iter *dest, int *chunk, bool *zc) 1226 { 1227 struct tls_context *tls_ctx = tls_get_ctx(sk); 1228 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1229 struct strp_msg *rxm = strp_msg(skb); 1230 int err = 0; 1231 1232 #ifdef CONFIG_TLS_DEVICE 1233 err = tls_device_decrypted(sk, skb); 1234 if (err < 0) 1235 return err; 1236 #endif 1237 if (!ctx->decrypted) { 1238 err = decrypt_internal(sk, skb, dest, NULL, chunk, zc); 1239 if (err < 0) { 1240 if (err == -EINPROGRESS) 1241 tls_advance_record_sn(sk, &tls_ctx->rx); 1242 1243 return err; 1244 } 1245 } else { 1246 *zc = false; 1247 } 1248 1249 rxm->offset += tls_ctx->rx.prepend_size; 1250 rxm->full_len -= tls_ctx->rx.overhead_size; 1251 tls_advance_record_sn(sk, &tls_ctx->rx); 1252 ctx->decrypted = true; 1253 ctx->saved_data_ready(sk); 1254 1255 return err; 1256 } 1257 1258 int decrypt_skb(struct sock *sk, struct sk_buff *skb, 1259 struct scatterlist *sgout) 1260 { 1261 bool zc = true; 1262 int chunk; 1263 1264 return decrypt_internal(sk, skb, NULL, sgout, &chunk, &zc); 1265 } 1266 1267 static bool tls_sw_advance_skb(struct sock *sk, struct sk_buff *skb, 1268 unsigned int len) 1269 { 1270 struct tls_context *tls_ctx = tls_get_ctx(sk); 1271 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1272 1273 if (skb) { 1274 struct strp_msg *rxm = strp_msg(skb); 1275 1276 if (len < rxm->full_len) { 1277 rxm->offset += len; 1278 rxm->full_len -= len; 1279 return false; 1280 } 1281 kfree_skb(skb); 1282 } 1283 1284 /* Finished with message */ 1285 ctx->recv_pkt = NULL; 1286 __strp_unpause(&ctx->strp); 1287 1288 return true; 1289 } 1290 1291 int tls_sw_recvmsg(struct sock *sk, 1292 struct msghdr *msg, 1293 size_t len, 1294 int nonblock, 1295 int flags, 1296 int *addr_len) 1297 { 1298 struct tls_context *tls_ctx = tls_get_ctx(sk); 1299 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1300 unsigned char control; 1301 struct strp_msg *rxm; 1302 struct sk_buff *skb; 1303 ssize_t copied = 0; 1304 bool cmsg = false; 1305 int target, err = 0; 1306 long timeo; 1307 bool is_kvec = msg->msg_iter.type & ITER_KVEC; 1308 int num_async = 0; 1309 1310 flags |= nonblock; 1311 1312 if (unlikely(flags & MSG_ERRQUEUE)) 1313 return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR); 1314 1315 lock_sock(sk); 1316 1317 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1318 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1319 do { 1320 bool zc = false; 1321 bool async = false; 1322 int chunk = 0; 1323 1324 skb = tls_wait_data(sk, flags, timeo, &err); 1325 if (!skb) 1326 goto recv_end; 1327 1328 rxm = strp_msg(skb); 1329 1330 if (!cmsg) { 1331 int cerr; 1332 1333 cerr = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE, 1334 sizeof(ctx->control), &ctx->control); 1335 cmsg = true; 1336 control = ctx->control; 1337 if (ctx->control != TLS_RECORD_TYPE_DATA) { 1338 if (cerr || msg->msg_flags & MSG_CTRUNC) { 1339 err = -EIO; 1340 goto recv_end; 1341 } 1342 } 1343 } else if (control != ctx->control) { 1344 goto recv_end; 1345 } 1346 1347 if (!ctx->decrypted) { 1348 int to_copy = rxm->full_len - tls_ctx->rx.overhead_size; 1349 1350 if (!is_kvec && to_copy <= len && 1351 likely(!(flags & MSG_PEEK))) 1352 zc = true; 1353 1354 err = decrypt_skb_update(sk, skb, &msg->msg_iter, 1355 &chunk, &zc); 1356 if (err < 0 && err != -EINPROGRESS) { 1357 tls_err_abort(sk, EBADMSG); 1358 goto recv_end; 1359 } 1360 1361 if (err == -EINPROGRESS) { 1362 async = true; 1363 num_async++; 1364 goto pick_next_record; 1365 } 1366 1367 ctx->decrypted = true; 1368 } 1369 1370 if (!zc) { 1371 chunk = min_t(unsigned int, rxm->full_len, len); 1372 1373 err = skb_copy_datagram_msg(skb, rxm->offset, msg, 1374 chunk); 1375 if (err < 0) 1376 goto recv_end; 1377 } 1378 1379 pick_next_record: 1380 copied += chunk; 1381 len -= chunk; 1382 if (likely(!(flags & MSG_PEEK))) { 1383 u8 control = ctx->control; 1384 1385 /* For async, drop current skb reference */ 1386 if (async) 1387 skb = NULL; 1388 1389 if (tls_sw_advance_skb(sk, skb, chunk)) { 1390 /* Return full control message to 1391 * userspace before trying to parse 1392 * another message type 1393 */ 1394 msg->msg_flags |= MSG_EOR; 1395 if (control != TLS_RECORD_TYPE_DATA) 1396 goto recv_end; 1397 } else { 1398 break; 1399 } 1400 } else { 1401 /* MSG_PEEK right now cannot look beyond current skb 1402 * from strparser, meaning we cannot advance skb here 1403 * and thus unpause strparser since we'd loose original 1404 * one. 1405 */ 1406 break; 1407 } 1408 1409 /* If we have a new message from strparser, continue now. */ 1410 if (copied >= target && !ctx->recv_pkt) 1411 break; 1412 } while (len); 1413 1414 recv_end: 1415 if (num_async) { 1416 /* Wait for all previously submitted records to be decrypted */ 1417 smp_store_mb(ctx->async_notify, true); 1418 if (atomic_read(&ctx->decrypt_pending)) { 1419 err = crypto_wait_req(-EINPROGRESS, &ctx->async_wait); 1420 if (err) { 1421 /* one of async decrypt failed */ 1422 tls_err_abort(sk, err); 1423 copied = 0; 1424 } 1425 } else { 1426 reinit_completion(&ctx->async_wait.completion); 1427 } 1428 WRITE_ONCE(ctx->async_notify, false); 1429 } 1430 1431 release_sock(sk); 1432 return copied ? : err; 1433 } 1434 1435 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 1436 struct pipe_inode_info *pipe, 1437 size_t len, unsigned int flags) 1438 { 1439 struct tls_context *tls_ctx = tls_get_ctx(sock->sk); 1440 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1441 struct strp_msg *rxm = NULL; 1442 struct sock *sk = sock->sk; 1443 struct sk_buff *skb; 1444 ssize_t copied = 0; 1445 int err = 0; 1446 long timeo; 1447 int chunk; 1448 bool zc = false; 1449 1450 lock_sock(sk); 1451 1452 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 1453 1454 skb = tls_wait_data(sk, flags, timeo, &err); 1455 if (!skb) 1456 goto splice_read_end; 1457 1458 /* splice does not support reading control messages */ 1459 if (ctx->control != TLS_RECORD_TYPE_DATA) { 1460 err = -ENOTSUPP; 1461 goto splice_read_end; 1462 } 1463 1464 if (!ctx->decrypted) { 1465 err = decrypt_skb_update(sk, skb, NULL, &chunk, &zc); 1466 1467 if (err < 0) { 1468 tls_err_abort(sk, EBADMSG); 1469 goto splice_read_end; 1470 } 1471 ctx->decrypted = true; 1472 } 1473 rxm = strp_msg(skb); 1474 1475 chunk = min_t(unsigned int, rxm->full_len, len); 1476 copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags); 1477 if (copied < 0) 1478 goto splice_read_end; 1479 1480 if (likely(!(flags & MSG_PEEK))) 1481 tls_sw_advance_skb(sk, skb, copied); 1482 1483 splice_read_end: 1484 release_sock(sk); 1485 return copied ? : err; 1486 } 1487 1488 unsigned int tls_sw_poll(struct file *file, struct socket *sock, 1489 struct poll_table_struct *wait) 1490 { 1491 unsigned int ret; 1492 struct sock *sk = sock->sk; 1493 struct tls_context *tls_ctx = tls_get_ctx(sk); 1494 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1495 1496 /* Grab POLLOUT and POLLHUP from the underlying socket */ 1497 ret = ctx->sk_poll(file, sock, wait); 1498 1499 /* Clear POLLIN bits, and set based on recv_pkt */ 1500 ret &= ~(POLLIN | POLLRDNORM); 1501 if (ctx->recv_pkt) 1502 ret |= POLLIN | POLLRDNORM; 1503 1504 return ret; 1505 } 1506 1507 static int tls_read_size(struct strparser *strp, struct sk_buff *skb) 1508 { 1509 struct tls_context *tls_ctx = tls_get_ctx(strp->sk); 1510 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1511 char header[TLS_HEADER_SIZE + MAX_IV_SIZE]; 1512 struct strp_msg *rxm = strp_msg(skb); 1513 size_t cipher_overhead; 1514 size_t data_len = 0; 1515 int ret; 1516 1517 /* Verify that we have a full TLS header, or wait for more data */ 1518 if (rxm->offset + tls_ctx->rx.prepend_size > skb->len) 1519 return 0; 1520 1521 /* Sanity-check size of on-stack buffer. */ 1522 if (WARN_ON(tls_ctx->rx.prepend_size > sizeof(header))) { 1523 ret = -EINVAL; 1524 goto read_failure; 1525 } 1526 1527 /* Linearize header to local buffer */ 1528 ret = skb_copy_bits(skb, rxm->offset, header, tls_ctx->rx.prepend_size); 1529 1530 if (ret < 0) 1531 goto read_failure; 1532 1533 ctx->control = header[0]; 1534 1535 data_len = ((header[4] & 0xFF) | (header[3] << 8)); 1536 1537 cipher_overhead = tls_ctx->rx.tag_size + tls_ctx->rx.iv_size; 1538 1539 if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead) { 1540 ret = -EMSGSIZE; 1541 goto read_failure; 1542 } 1543 if (data_len < cipher_overhead) { 1544 ret = -EBADMSG; 1545 goto read_failure; 1546 } 1547 1548 if (header[1] != TLS_VERSION_MINOR(tls_ctx->crypto_recv.info.version) || 1549 header[2] != TLS_VERSION_MAJOR(tls_ctx->crypto_recv.info.version)) { 1550 ret = -EINVAL; 1551 goto read_failure; 1552 } 1553 1554 #ifdef CONFIG_TLS_DEVICE 1555 handle_device_resync(strp->sk, TCP_SKB_CB(skb)->seq + rxm->offset, 1556 *(u64*)tls_ctx->rx.rec_seq); 1557 #endif 1558 return data_len + TLS_HEADER_SIZE; 1559 1560 read_failure: 1561 tls_err_abort(strp->sk, ret); 1562 1563 return ret; 1564 } 1565 1566 static void tls_queue(struct strparser *strp, struct sk_buff *skb) 1567 { 1568 struct tls_context *tls_ctx = tls_get_ctx(strp->sk); 1569 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1570 1571 ctx->decrypted = false; 1572 1573 ctx->recv_pkt = skb; 1574 strp_pause(strp); 1575 1576 ctx->saved_data_ready(strp->sk); 1577 } 1578 1579 static void tls_data_ready(struct sock *sk) 1580 { 1581 struct tls_context *tls_ctx = tls_get_ctx(sk); 1582 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1583 1584 strp_data_ready(&ctx->strp); 1585 } 1586 1587 void tls_sw_free_resources_tx(struct sock *sk) 1588 { 1589 struct tls_context *tls_ctx = tls_get_ctx(sk); 1590 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 1591 struct tls_rec *rec, *tmp; 1592 1593 /* Wait for any pending async encryptions to complete */ 1594 smp_store_mb(ctx->async_notify, true); 1595 if (atomic_read(&ctx->encrypt_pending)) 1596 crypto_wait_req(-EINPROGRESS, &ctx->async_wait); 1597 1598 cancel_delayed_work_sync(&ctx->tx_work.work); 1599 1600 /* Tx whatever records we can transmit and abandon the rest */ 1601 tls_tx_records(sk, -1); 1602 1603 /* Free up un-sent records in tx_list. First, free 1604 * the partially sent record if any at head of tx_list. 1605 */ 1606 if (tls_ctx->partially_sent_record) { 1607 struct scatterlist *sg = tls_ctx->partially_sent_record; 1608 1609 while (1) { 1610 put_page(sg_page(sg)); 1611 sk_mem_uncharge(sk, sg->length); 1612 1613 if (sg_is_last(sg)) 1614 break; 1615 sg++; 1616 } 1617 1618 tls_ctx->partially_sent_record = NULL; 1619 1620 rec = list_first_entry(&ctx->tx_list, 1621 struct tls_rec, list); 1622 1623 free_sg(sk, &rec->sg_plaintext_data[1], 1624 &rec->sg_plaintext_num_elem, 1625 &rec->sg_plaintext_size); 1626 1627 list_del(&rec->list); 1628 kfree(rec); 1629 } 1630 1631 list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) { 1632 free_sg(sk, &rec->sg_encrypted_data[1], 1633 &rec->sg_encrypted_num_elem, 1634 &rec->sg_encrypted_size); 1635 1636 free_sg(sk, &rec->sg_plaintext_data[1], 1637 &rec->sg_plaintext_num_elem, 1638 &rec->sg_plaintext_size); 1639 1640 list_del(&rec->list); 1641 kfree(rec); 1642 } 1643 1644 crypto_free_aead(ctx->aead_send); 1645 tls_free_open_rec(sk); 1646 1647 kfree(ctx); 1648 } 1649 1650 void tls_sw_release_resources_rx(struct sock *sk) 1651 { 1652 struct tls_context *tls_ctx = tls_get_ctx(sk); 1653 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1654 1655 if (ctx->aead_recv) { 1656 kfree_skb(ctx->recv_pkt); 1657 ctx->recv_pkt = NULL; 1658 crypto_free_aead(ctx->aead_recv); 1659 strp_stop(&ctx->strp); 1660 write_lock_bh(&sk->sk_callback_lock); 1661 sk->sk_data_ready = ctx->saved_data_ready; 1662 write_unlock_bh(&sk->sk_callback_lock); 1663 release_sock(sk); 1664 strp_done(&ctx->strp); 1665 lock_sock(sk); 1666 } 1667 } 1668 1669 void tls_sw_free_resources_rx(struct sock *sk) 1670 { 1671 struct tls_context *tls_ctx = tls_get_ctx(sk); 1672 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1673 1674 tls_sw_release_resources_rx(sk); 1675 1676 kfree(ctx); 1677 } 1678 1679 /* The work handler to transmitt the encrypted records in tx_list */ 1680 static void tx_work_handler(struct work_struct *work) 1681 { 1682 struct delayed_work *delayed_work = to_delayed_work(work); 1683 struct tx_work *tx_work = container_of(delayed_work, 1684 struct tx_work, work); 1685 struct sock *sk = tx_work->sk; 1686 struct tls_context *tls_ctx = tls_get_ctx(sk); 1687 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 1688 1689 if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) 1690 return; 1691 1692 lock_sock(sk); 1693 tls_tx_records(sk, -1); 1694 release_sock(sk); 1695 } 1696 1697 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx) 1698 { 1699 struct tls_crypto_info *crypto_info; 1700 struct tls12_crypto_info_aes_gcm_128 *gcm_128_info; 1701 struct tls_sw_context_tx *sw_ctx_tx = NULL; 1702 struct tls_sw_context_rx *sw_ctx_rx = NULL; 1703 struct cipher_context *cctx; 1704 struct crypto_aead **aead; 1705 struct strp_callbacks cb; 1706 u16 nonce_size, tag_size, iv_size, rec_seq_size; 1707 char *iv, *rec_seq; 1708 int rc = 0; 1709 1710 if (!ctx) { 1711 rc = -EINVAL; 1712 goto out; 1713 } 1714 1715 if (tx) { 1716 if (!ctx->priv_ctx_tx) { 1717 sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL); 1718 if (!sw_ctx_tx) { 1719 rc = -ENOMEM; 1720 goto out; 1721 } 1722 ctx->priv_ctx_tx = sw_ctx_tx; 1723 } else { 1724 sw_ctx_tx = 1725 (struct tls_sw_context_tx *)ctx->priv_ctx_tx; 1726 } 1727 } else { 1728 if (!ctx->priv_ctx_rx) { 1729 sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL); 1730 if (!sw_ctx_rx) { 1731 rc = -ENOMEM; 1732 goto out; 1733 } 1734 ctx->priv_ctx_rx = sw_ctx_rx; 1735 } else { 1736 sw_ctx_rx = 1737 (struct tls_sw_context_rx *)ctx->priv_ctx_rx; 1738 } 1739 } 1740 1741 if (tx) { 1742 crypto_init_wait(&sw_ctx_tx->async_wait); 1743 crypto_info = &ctx->crypto_send.info; 1744 cctx = &ctx->tx; 1745 aead = &sw_ctx_tx->aead_send; 1746 INIT_LIST_HEAD(&sw_ctx_tx->tx_list); 1747 INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler); 1748 sw_ctx_tx->tx_work.sk = sk; 1749 } else { 1750 crypto_init_wait(&sw_ctx_rx->async_wait); 1751 crypto_info = &ctx->crypto_recv.info; 1752 cctx = &ctx->rx; 1753 aead = &sw_ctx_rx->aead_recv; 1754 } 1755 1756 switch (crypto_info->cipher_type) { 1757 case TLS_CIPHER_AES_GCM_128: { 1758 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE; 1759 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE; 1760 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE; 1761 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv; 1762 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE; 1763 rec_seq = 1764 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq; 1765 gcm_128_info = 1766 (struct tls12_crypto_info_aes_gcm_128 *)crypto_info; 1767 break; 1768 } 1769 default: 1770 rc = -EINVAL; 1771 goto free_priv; 1772 } 1773 1774 /* Sanity-check the IV size for stack allocations. */ 1775 if (iv_size > MAX_IV_SIZE || nonce_size > MAX_IV_SIZE) { 1776 rc = -EINVAL; 1777 goto free_priv; 1778 } 1779 1780 cctx->prepend_size = TLS_HEADER_SIZE + nonce_size; 1781 cctx->tag_size = tag_size; 1782 cctx->overhead_size = cctx->prepend_size + cctx->tag_size; 1783 cctx->iv_size = iv_size; 1784 cctx->iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 1785 GFP_KERNEL); 1786 if (!cctx->iv) { 1787 rc = -ENOMEM; 1788 goto free_priv; 1789 } 1790 memcpy(cctx->iv, gcm_128_info->salt, TLS_CIPHER_AES_GCM_128_SALT_SIZE); 1791 memcpy(cctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size); 1792 cctx->rec_seq_size = rec_seq_size; 1793 cctx->rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL); 1794 if (!cctx->rec_seq) { 1795 rc = -ENOMEM; 1796 goto free_iv; 1797 } 1798 1799 if (!*aead) { 1800 *aead = crypto_alloc_aead("gcm(aes)", 0, 0); 1801 if (IS_ERR(*aead)) { 1802 rc = PTR_ERR(*aead); 1803 *aead = NULL; 1804 goto free_rec_seq; 1805 } 1806 } 1807 1808 ctx->push_pending_record = tls_sw_push_pending_record; 1809 1810 rc = crypto_aead_setkey(*aead, gcm_128_info->key, 1811 TLS_CIPHER_AES_GCM_128_KEY_SIZE); 1812 if (rc) 1813 goto free_aead; 1814 1815 rc = crypto_aead_setauthsize(*aead, cctx->tag_size); 1816 if (rc) 1817 goto free_aead; 1818 1819 if (sw_ctx_rx) { 1820 /* Set up strparser */ 1821 memset(&cb, 0, sizeof(cb)); 1822 cb.rcv_msg = tls_queue; 1823 cb.parse_msg = tls_read_size; 1824 1825 strp_init(&sw_ctx_rx->strp, sk, &cb); 1826 1827 write_lock_bh(&sk->sk_callback_lock); 1828 sw_ctx_rx->saved_data_ready = sk->sk_data_ready; 1829 sk->sk_data_ready = tls_data_ready; 1830 write_unlock_bh(&sk->sk_callback_lock); 1831 1832 sw_ctx_rx->sk_poll = sk->sk_socket->ops->poll; 1833 1834 strp_check_rcv(&sw_ctx_rx->strp); 1835 } 1836 1837 goto out; 1838 1839 free_aead: 1840 crypto_free_aead(*aead); 1841 *aead = NULL; 1842 free_rec_seq: 1843 kfree(cctx->rec_seq); 1844 cctx->rec_seq = NULL; 1845 free_iv: 1846 kfree(cctx->iv); 1847 cctx->iv = NULL; 1848 free_priv: 1849 if (tx) { 1850 kfree(ctx->priv_ctx_tx); 1851 ctx->priv_ctx_tx = NULL; 1852 } else { 1853 kfree(ctx->priv_ctx_rx); 1854 ctx->priv_ctx_rx = NULL; 1855 } 1856 out: 1857 return rc; 1858 } 1859