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 * Copyright (c) 2018, Covalent IO, Inc. http://covalent.io 8 * 9 * This software is available to you under a choice of one of two 10 * licenses. You may choose to be licensed under the terms of the GNU 11 * General Public License (GPL) Version 2, available from the file 12 * COPYING in the main directory of this source tree, or the 13 * OpenIB.org BSD license below: 14 * 15 * Redistribution and use in source and binary forms, with or 16 * without modification, are permitted provided that the following 17 * conditions are met: 18 * 19 * - Redistributions of source code must retain the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer. 22 * 23 * - Redistributions in binary form must reproduce the above 24 * copyright notice, this list of conditions and the following 25 * disclaimer in the documentation and/or other materials 26 * provided with the distribution. 27 * 28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 29 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 30 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 31 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 32 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 33 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 34 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 35 * SOFTWARE. 36 */ 37 38 #include <linux/bug.h> 39 #include <linux/sched/signal.h> 40 #include <linux/module.h> 41 #include <linux/kernel.h> 42 #include <linux/splice.h> 43 #include <crypto/aead.h> 44 45 #include <net/strparser.h> 46 #include <net/tls.h> 47 #include <trace/events/sock.h> 48 49 #include "tls.h" 50 51 struct tls_decrypt_arg { 52 struct_group(inargs, 53 bool zc; 54 bool async; 55 bool async_done; 56 u8 tail; 57 ); 58 59 struct sk_buff *skb; 60 }; 61 62 struct tls_decrypt_ctx { 63 struct sock *sk; 64 u8 iv[TLS_MAX_IV_SIZE]; 65 u8 aad[TLS_MAX_AAD_SIZE]; 66 u8 tail; 67 bool free_sgout; 68 struct scatterlist sg[]; 69 }; 70 71 noinline void tls_err_abort(struct sock *sk, int err) 72 { 73 WARN_ON_ONCE(err >= 0); 74 /* sk->sk_err should contain a positive error code. */ 75 WRITE_ONCE(sk->sk_err, -err); 76 /* Paired with smp_rmb() in tcp_poll() */ 77 smp_wmb(); 78 sk_error_report(sk); 79 } 80 81 static int __skb_nsg(struct sk_buff *skb, int offset, int len, 82 unsigned int recursion_level) 83 { 84 int start = skb_headlen(skb); 85 int i, chunk = start - offset; 86 struct sk_buff *frag_iter; 87 int elt = 0; 88 89 if (unlikely(recursion_level >= 24)) 90 return -EMSGSIZE; 91 92 if (chunk > 0) { 93 if (chunk > len) 94 chunk = len; 95 elt++; 96 len -= chunk; 97 if (len == 0) 98 return elt; 99 offset += chunk; 100 } 101 102 for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { 103 int end; 104 105 WARN_ON(start > offset + len); 106 107 end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]); 108 chunk = end - offset; 109 if (chunk > 0) { 110 if (chunk > len) 111 chunk = len; 112 elt++; 113 len -= chunk; 114 if (len == 0) 115 return elt; 116 offset += chunk; 117 } 118 start = end; 119 } 120 121 if (unlikely(skb_has_frag_list(skb))) { 122 skb_walk_frags(skb, frag_iter) { 123 int end, ret; 124 125 WARN_ON(start > offset + len); 126 127 end = start + frag_iter->len; 128 chunk = end - offset; 129 if (chunk > 0) { 130 if (chunk > len) 131 chunk = len; 132 ret = __skb_nsg(frag_iter, offset - start, chunk, 133 recursion_level + 1); 134 if (unlikely(ret < 0)) 135 return ret; 136 elt += ret; 137 len -= chunk; 138 if (len == 0) 139 return elt; 140 offset += chunk; 141 } 142 start = end; 143 } 144 } 145 BUG_ON(len); 146 return elt; 147 } 148 149 /* Return the number of scatterlist elements required to completely map the 150 * skb, or -EMSGSIZE if the recursion depth is exceeded. 151 */ 152 static int skb_nsg(struct sk_buff *skb, int offset, int len) 153 { 154 return __skb_nsg(skb, offset, len, 0); 155 } 156 157 static int tls_padding_length(struct tls_prot_info *prot, struct sk_buff *skb, 158 struct tls_decrypt_arg *darg) 159 { 160 struct strp_msg *rxm = strp_msg(skb); 161 struct tls_msg *tlm = tls_msg(skb); 162 int sub = 0; 163 164 /* Determine zero-padding length */ 165 if (prot->version == TLS_1_3_VERSION) { 166 int offset = rxm->full_len - TLS_TAG_SIZE - 1; 167 char content_type = darg->zc ? darg->tail : 0; 168 int err; 169 170 while (content_type == 0) { 171 if (offset < prot->prepend_size) 172 return -EBADMSG; 173 err = skb_copy_bits(skb, rxm->offset + offset, 174 &content_type, 1); 175 if (err) 176 return err; 177 if (content_type) 178 break; 179 sub++; 180 offset--; 181 } 182 tlm->control = content_type; 183 } 184 return sub; 185 } 186 187 static void tls_decrypt_done(void *data, int err) 188 { 189 struct aead_request *aead_req = data; 190 struct crypto_aead *aead = crypto_aead_reqtfm(aead_req); 191 struct scatterlist *sgout = aead_req->dst; 192 struct tls_sw_context_rx *ctx; 193 struct tls_decrypt_ctx *dctx; 194 struct tls_context *tls_ctx; 195 struct scatterlist *sg; 196 unsigned int pages; 197 struct sock *sk; 198 int aead_size; 199 200 /* If requests get too backlogged crypto API returns -EBUSY and calls 201 * ->complete(-EINPROGRESS) immediately followed by ->complete(0) 202 * to make waiting for backlog to flush with crypto_wait_req() easier. 203 * First wait converts -EBUSY -> -EINPROGRESS, and the second one 204 * -EINPROGRESS -> 0. 205 * We have a single struct crypto_async_request per direction, this 206 * scheme doesn't help us, so just ignore the first ->complete(). 207 */ 208 if (err == -EINPROGRESS) 209 return; 210 211 aead_size = sizeof(*aead_req) + crypto_aead_reqsize(aead); 212 aead_size = ALIGN(aead_size, __alignof__(*dctx)); 213 dctx = (void *)((u8 *)aead_req + aead_size); 214 215 sk = dctx->sk; 216 tls_ctx = tls_get_ctx(sk); 217 ctx = tls_sw_ctx_rx(tls_ctx); 218 219 /* Propagate if there was an err */ 220 if (err) { 221 if (err == -EBADMSG) 222 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR); 223 ctx->async_wait.err = err; 224 tls_err_abort(sk, err); 225 } 226 227 /* Free the destination pages if skb was not decrypted inplace */ 228 if (dctx->free_sgout) { 229 /* Skip the first S/G entry as it points to AAD */ 230 for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) { 231 if (!sg) 232 break; 233 put_page(sg_page(sg)); 234 } 235 } 236 237 kfree(aead_req); 238 239 if (atomic_dec_and_test(&ctx->decrypt_pending)) 240 complete(&ctx->async_wait.completion); 241 } 242 243 static int tls_decrypt_async_wait(struct tls_sw_context_rx *ctx) 244 { 245 if (!atomic_dec_and_test(&ctx->decrypt_pending)) 246 crypto_wait_req(-EINPROGRESS, &ctx->async_wait); 247 atomic_inc(&ctx->decrypt_pending); 248 249 __skb_queue_purge(&ctx->async_hold); 250 return ctx->async_wait.err; 251 } 252 253 static int tls_do_decryption(struct sock *sk, 254 struct scatterlist *sgin, 255 struct scatterlist *sgout, 256 char *iv_recv, 257 size_t data_len, 258 struct aead_request *aead_req, 259 struct tls_decrypt_arg *darg) 260 { 261 struct tls_context *tls_ctx = tls_get_ctx(sk); 262 struct tls_prot_info *prot = &tls_ctx->prot_info; 263 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 264 int ret; 265 266 aead_request_set_tfm(aead_req, ctx->aead_recv); 267 aead_request_set_ad(aead_req, prot->aad_size); 268 aead_request_set_crypt(aead_req, sgin, sgout, 269 data_len + prot->tag_size, 270 (u8 *)iv_recv); 271 272 if (darg->async) { 273 aead_request_set_callback(aead_req, 274 CRYPTO_TFM_REQ_MAY_BACKLOG, 275 tls_decrypt_done, aead_req); 276 DEBUG_NET_WARN_ON_ONCE(atomic_read(&ctx->decrypt_pending) < 1); 277 atomic_inc(&ctx->decrypt_pending); 278 } else { 279 DECLARE_CRYPTO_WAIT(wait); 280 281 aead_request_set_callback(aead_req, 282 CRYPTO_TFM_REQ_MAY_BACKLOG, 283 crypto_req_done, &wait); 284 ret = crypto_aead_decrypt(aead_req); 285 if (ret == -EINPROGRESS || ret == -EBUSY) 286 ret = crypto_wait_req(ret, &wait); 287 return ret; 288 } 289 290 ret = crypto_aead_decrypt(aead_req); 291 if (ret == -EINPROGRESS) 292 return 0; 293 294 if (ret == -EBUSY) { 295 ret = tls_decrypt_async_wait(ctx); 296 darg->async_done = true; 297 /* all completions have run, we're not doing async anymore */ 298 darg->async = false; 299 return ret; 300 } 301 302 atomic_dec(&ctx->decrypt_pending); 303 darg->async = false; 304 305 return ret; 306 } 307 308 static void tls_trim_both_msgs(struct sock *sk, int target_size) 309 { 310 struct tls_context *tls_ctx = tls_get_ctx(sk); 311 struct tls_prot_info *prot = &tls_ctx->prot_info; 312 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 313 struct tls_rec *rec = ctx->open_rec; 314 315 sk_msg_trim(sk, &rec->msg_plaintext, target_size); 316 if (target_size > 0) 317 target_size += prot->overhead_size; 318 sk_msg_trim(sk, &rec->msg_encrypted, target_size); 319 } 320 321 static int tls_alloc_encrypted_msg(struct sock *sk, int len) 322 { 323 struct tls_context *tls_ctx = tls_get_ctx(sk); 324 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 325 struct tls_rec *rec = ctx->open_rec; 326 struct sk_msg *msg_en = &rec->msg_encrypted; 327 328 return sk_msg_alloc(sk, msg_en, len, 0); 329 } 330 331 static int tls_clone_plaintext_msg(struct sock *sk, int required) 332 { 333 struct tls_context *tls_ctx = tls_get_ctx(sk); 334 struct tls_prot_info *prot = &tls_ctx->prot_info; 335 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 336 struct tls_rec *rec = ctx->open_rec; 337 struct sk_msg *msg_pl = &rec->msg_plaintext; 338 struct sk_msg *msg_en = &rec->msg_encrypted; 339 int skip, len; 340 341 /* We add page references worth len bytes from encrypted sg 342 * at the end of plaintext sg. It is guaranteed that msg_en 343 * has enough required room (ensured by caller). 344 */ 345 len = required - msg_pl->sg.size; 346 347 /* Skip initial bytes in msg_en's data to be able to use 348 * same offset of both plain and encrypted data. 349 */ 350 skip = prot->prepend_size + msg_pl->sg.size; 351 352 return sk_msg_clone(sk, msg_pl, msg_en, skip, len); 353 } 354 355 static struct tls_rec *tls_get_rec(struct sock *sk) 356 { 357 struct tls_context *tls_ctx = tls_get_ctx(sk); 358 struct tls_prot_info *prot = &tls_ctx->prot_info; 359 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 360 struct sk_msg *msg_pl, *msg_en; 361 struct tls_rec *rec; 362 int mem_size; 363 364 mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send); 365 366 rec = kzalloc(mem_size, sk->sk_allocation); 367 if (!rec) 368 return NULL; 369 370 msg_pl = &rec->msg_plaintext; 371 msg_en = &rec->msg_encrypted; 372 373 sk_msg_init(msg_pl); 374 sk_msg_init(msg_en); 375 376 sg_init_table(rec->sg_aead_in, 2); 377 sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size); 378 sg_unmark_end(&rec->sg_aead_in[1]); 379 380 sg_init_table(rec->sg_aead_out, 2); 381 sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size); 382 sg_unmark_end(&rec->sg_aead_out[1]); 383 384 rec->sk = sk; 385 386 return rec; 387 } 388 389 static void tls_free_rec(struct sock *sk, struct tls_rec *rec) 390 { 391 sk_msg_free(sk, &rec->msg_encrypted); 392 sk_msg_free(sk, &rec->msg_plaintext); 393 kfree(rec); 394 } 395 396 static void tls_free_open_rec(struct sock *sk) 397 { 398 struct tls_context *tls_ctx = tls_get_ctx(sk); 399 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 400 struct tls_rec *rec = ctx->open_rec; 401 402 if (rec) { 403 tls_free_rec(sk, rec); 404 ctx->open_rec = NULL; 405 } 406 } 407 408 int tls_tx_records(struct sock *sk, int flags) 409 { 410 struct tls_context *tls_ctx = tls_get_ctx(sk); 411 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 412 struct tls_rec *rec, *tmp; 413 struct sk_msg *msg_en; 414 int tx_flags, rc = 0; 415 416 if (tls_is_partially_sent_record(tls_ctx)) { 417 rec = list_first_entry(&ctx->tx_list, 418 struct tls_rec, list); 419 420 if (flags == -1) 421 tx_flags = rec->tx_flags; 422 else 423 tx_flags = flags; 424 425 rc = tls_push_partial_record(sk, tls_ctx, tx_flags); 426 if (rc) 427 goto tx_err; 428 429 /* Full record has been transmitted. 430 * Remove the head of tx_list 431 */ 432 list_del(&rec->list); 433 sk_msg_free(sk, &rec->msg_plaintext); 434 kfree(rec); 435 } 436 437 /* Tx all ready records */ 438 list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) { 439 if (READ_ONCE(rec->tx_ready)) { 440 if (flags == -1) 441 tx_flags = rec->tx_flags; 442 else 443 tx_flags = flags; 444 445 msg_en = &rec->msg_encrypted; 446 rc = tls_push_sg(sk, tls_ctx, 447 &msg_en->sg.data[msg_en->sg.curr], 448 0, tx_flags); 449 if (rc) 450 goto tx_err; 451 452 list_del(&rec->list); 453 sk_msg_free(sk, &rec->msg_plaintext); 454 kfree(rec); 455 } else { 456 break; 457 } 458 } 459 460 tx_err: 461 if (rc < 0 && rc != -EAGAIN && rc != -EINTR && rc != -ERESTARTSYS) 462 tls_err_abort(sk, rc); 463 464 return rc; 465 } 466 467 static void tls_encrypt_done(void *data, int err) 468 { 469 struct tls_sw_context_tx *ctx; 470 struct tls_context *tls_ctx; 471 struct tls_prot_info *prot; 472 struct tls_rec *rec = data; 473 struct scatterlist *sge; 474 struct sk_msg *msg_en; 475 struct sock *sk; 476 477 if (err == -EINPROGRESS) /* see the comment in tls_decrypt_done() */ 478 return; 479 480 msg_en = &rec->msg_encrypted; 481 482 sk = rec->sk; 483 tls_ctx = tls_get_ctx(sk); 484 prot = &tls_ctx->prot_info; 485 ctx = tls_sw_ctx_tx(tls_ctx); 486 487 sge = sk_msg_elem(msg_en, msg_en->sg.curr); 488 sge->offset -= prot->prepend_size; 489 sge->length += prot->prepend_size; 490 491 /* Check if error is previously set on socket */ 492 if (err || sk->sk_err) { 493 rec = NULL; 494 495 /* If err is already set on socket, return the same code */ 496 if (sk->sk_err) { 497 ctx->async_wait.err = -sk->sk_err; 498 } else { 499 ctx->async_wait.err = err; 500 tls_err_abort(sk, err); 501 } 502 } 503 504 if (rec) { 505 struct tls_rec *first_rec; 506 507 /* Mark the record as ready for transmission */ 508 smp_store_mb(rec->tx_ready, true); 509 510 /* If received record is at head of tx_list, schedule tx */ 511 first_rec = list_first_entry(&ctx->tx_list, 512 struct tls_rec, list); 513 if (rec == first_rec) { 514 /* Schedule the transmission */ 515 if (!test_and_set_bit(BIT_TX_SCHEDULED, 516 &ctx->tx_bitmask)) 517 schedule_delayed_work(&ctx->tx_work.work, 1); 518 } 519 } 520 521 if (atomic_dec_and_test(&ctx->encrypt_pending)) 522 complete(&ctx->async_wait.completion); 523 } 524 525 static int tls_encrypt_async_wait(struct tls_sw_context_tx *ctx) 526 { 527 if (!atomic_dec_and_test(&ctx->encrypt_pending)) 528 crypto_wait_req(-EINPROGRESS, &ctx->async_wait); 529 atomic_inc(&ctx->encrypt_pending); 530 531 return ctx->async_wait.err; 532 } 533 534 static int tls_do_encryption(struct sock *sk, 535 struct tls_context *tls_ctx, 536 struct tls_sw_context_tx *ctx, 537 struct aead_request *aead_req, 538 size_t data_len, u32 start) 539 { 540 struct tls_prot_info *prot = &tls_ctx->prot_info; 541 struct tls_rec *rec = ctx->open_rec; 542 struct sk_msg *msg_en = &rec->msg_encrypted; 543 struct scatterlist *sge = sk_msg_elem(msg_en, start); 544 int rc, iv_offset = 0; 545 546 /* For CCM based ciphers, first byte of IV is a constant */ 547 switch (prot->cipher_type) { 548 case TLS_CIPHER_AES_CCM_128: 549 rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE; 550 iv_offset = 1; 551 break; 552 case TLS_CIPHER_SM4_CCM: 553 rec->iv_data[0] = TLS_SM4_CCM_IV_B0_BYTE; 554 iv_offset = 1; 555 break; 556 } 557 558 memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv, 559 prot->iv_size + prot->salt_size); 560 561 tls_xor_iv_with_seq(prot, rec->iv_data + iv_offset, 562 tls_ctx->tx.rec_seq); 563 564 sge->offset += prot->prepend_size; 565 sge->length -= prot->prepend_size; 566 567 msg_en->sg.curr = start; 568 569 aead_request_set_tfm(aead_req, ctx->aead_send); 570 aead_request_set_ad(aead_req, prot->aad_size); 571 aead_request_set_crypt(aead_req, rec->sg_aead_in, 572 rec->sg_aead_out, 573 data_len, rec->iv_data); 574 575 aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG, 576 tls_encrypt_done, rec); 577 578 /* Add the record in tx_list */ 579 list_add_tail((struct list_head *)&rec->list, &ctx->tx_list); 580 DEBUG_NET_WARN_ON_ONCE(atomic_read(&ctx->encrypt_pending) < 1); 581 atomic_inc(&ctx->encrypt_pending); 582 583 rc = crypto_aead_encrypt(aead_req); 584 if (rc == -EBUSY) { 585 rc = tls_encrypt_async_wait(ctx); 586 rc = rc ?: -EINPROGRESS; 587 /* 588 * The async callback tls_encrypt_done() has already 589 * decremented encrypt_pending and restored the sge on 590 * both success and error. Skip the synchronous cleanup 591 * below on error, just remove the record and return. 592 */ 593 if (rc != -EINPROGRESS) { 594 list_del(&rec->list); 595 return rc; 596 } 597 } 598 if (!rc || rc != -EINPROGRESS) { 599 atomic_dec(&ctx->encrypt_pending); 600 sge->offset -= prot->prepend_size; 601 sge->length += prot->prepend_size; 602 } 603 604 if (!rc) { 605 WRITE_ONCE(rec->tx_ready, true); 606 } else if (rc != -EINPROGRESS) { 607 list_del(&rec->list); 608 return rc; 609 } 610 611 /* Unhook the record from context if encryption is not failure */ 612 ctx->open_rec = NULL; 613 tls_advance_record_sn(sk, prot, &tls_ctx->tx); 614 return rc; 615 } 616 617 static int tls_push_record(struct sock *sk, int flags, 618 unsigned char record_type) 619 { 620 struct tls_context *tls_ctx = tls_get_ctx(sk); 621 struct tls_prot_info *prot = &tls_ctx->prot_info; 622 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 623 struct tls_rec *rec = ctx->open_rec; 624 struct sk_msg *msg_pl, *msg_en; 625 struct aead_request *req; 626 int rc; 627 u32 i; 628 629 if (!rec) 630 return 0; 631 632 msg_pl = &rec->msg_plaintext; 633 msg_en = &rec->msg_encrypted; 634 635 rec->tx_flags = flags; 636 req = &rec->aead_req; 637 638 i = msg_pl->sg.end; 639 sk_msg_iter_var_prev(i); 640 641 /* msg_pl->sg.data is a ring; data[MAX+1] is reserved for the wrap 642 * link (frags won't use it). 'i' is now the last filled entry: 643 * 644 * i end start 645 * v v v [ rsv ] 646 * [ d ][ d ][ ][ ]...[ ][ d ][ d ][ d ][chain] 647 * ^ END v 648 * `-----------------------------------------' 649 * 650 * Note that SGL does not allow chain-after-chain, so for TLS 1.3, 651 * we must make sure we don't create the wrap entry and then chain 652 * link to content_type immediately at index 0. 653 */ 654 if (i < msg_pl->sg.start) 655 sg_chain(msg_pl->sg.data, ARRAY_SIZE(msg_pl->sg.data), 656 msg_pl->sg.data); 657 658 rec->content_type = record_type; 659 if (prot->version == TLS_1_3_VERSION) { 660 /* Add content type to end of message. No padding added */ 661 sg_set_buf(&rec->sg_content_type, &rec->content_type, 1); 662 sg_mark_end(&rec->sg_content_type); 663 sg_chain(msg_pl->sg.data, i + 2, &rec->sg_content_type); 664 } else { 665 sg_mark_end(sk_msg_elem(msg_pl, i)); 666 } 667 668 i = msg_pl->sg.start; 669 sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]); 670 671 i = msg_en->sg.end; 672 sk_msg_iter_var_prev(i); 673 sg_mark_end(sk_msg_elem(msg_en, i)); 674 675 i = msg_en->sg.start; 676 sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]); 677 678 tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size, 679 tls_ctx->tx.rec_seq, record_type, prot); 680 681 tls_fill_prepend(tls_ctx, 682 page_address(sg_page(&msg_en->sg.data[i])) + 683 msg_en->sg.data[i].offset, 684 msg_pl->sg.size + prot->tail_size, 685 record_type); 686 687 tls_ctx->pending_open_record_frags = false; 688 689 rc = tls_do_encryption(sk, tls_ctx, ctx, req, 690 msg_pl->sg.size + prot->tail_size, i); 691 if (rc < 0) { 692 if (rc != -EINPROGRESS) 693 tls_err_abort(sk, -EBADMSG); 694 ctx->async_capable = 1; 695 return rc; 696 } 697 698 return tls_tx_records(sk, flags); 699 } 700 701 static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk, 702 u8 record_type, ssize_t *copied, int flags) 703 { 704 int err; 705 706 err = tls_push_record(sk, flags, record_type); 707 if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) { 708 *copied -= sk_msg_free(sk, msg); 709 tls_free_open_rec(sk); 710 err = -sk->sk_err; 711 } 712 return err; 713 } 714 715 static int tls_sw_push_pending_record(struct sock *sk, int flags) 716 { 717 struct tls_context *tls_ctx = tls_get_ctx(sk); 718 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 719 struct tls_rec *rec = ctx->open_rec; 720 struct sk_msg *msg_pl; 721 size_t copied; 722 723 if (!rec) 724 return 0; 725 726 msg_pl = &rec->msg_plaintext; 727 copied = msg_pl->sg.size; 728 if (!copied) 729 return 0; 730 731 return bpf_exec_tx_verdict(msg_pl, sk, TLS_RECORD_TYPE_DATA, 732 &copied, flags); 733 } 734 735 static int tls_sw_sendmsg_splice(struct sock *sk, struct msghdr *msg, 736 struct sk_msg *msg_pl, size_t try_to_copy, 737 ssize_t *copied) 738 { 739 struct page *page = NULL, **pages = &page; 740 741 do { 742 ssize_t part; 743 size_t off; 744 745 part = iov_iter_extract_pages(&msg->msg_iter, &pages, 746 try_to_copy, 1, 0, &off); 747 if (part <= 0) 748 return part ?: -EIO; 749 750 if (WARN_ON_ONCE(!sendpage_ok(page))) { 751 iov_iter_revert(&msg->msg_iter, part); 752 return -EIO; 753 } 754 755 sk_msg_page_add(msg_pl, page, part, off); 756 msg_pl->sg.copybreak = 0; 757 msg_pl->sg.curr = msg_pl->sg.end; 758 sk_mem_charge(sk, part); 759 *copied += part; 760 try_to_copy -= part; 761 } while (try_to_copy && !sk_msg_full(msg_pl)); 762 763 return 0; 764 } 765 766 static int tls_sw_sendmsg_locked(struct sock *sk, struct msghdr *msg, 767 size_t size) 768 { 769 long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 770 struct tls_context *tls_ctx = tls_get_ctx(sk); 771 struct tls_prot_info *prot = &tls_ctx->prot_info; 772 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 773 bool async_capable = ctx->async_capable; 774 unsigned char record_type = TLS_RECORD_TYPE_DATA; 775 bool is_kvec = iov_iter_is_kvec(&msg->msg_iter); 776 bool eor = !(msg->msg_flags & MSG_MORE); 777 size_t try_to_copy; 778 ssize_t copied = 0; 779 struct sk_msg *msg_pl, *msg_en; 780 struct tls_rec *rec; 781 int required_size; 782 int num_async = 0; 783 bool full_record; 784 int record_room; 785 int num_zc = 0; 786 int orig_size; 787 int ret = 0; 788 789 if (!eor && (msg->msg_flags & MSG_EOR)) 790 return -EINVAL; 791 792 if (unlikely(msg->msg_controllen)) { 793 ret = tls_process_cmsg(sk, msg, &record_type); 794 if (ret) { 795 if (ret == -EINPROGRESS) 796 num_async++; 797 else if (ret != -EAGAIN) 798 goto end; 799 } 800 } 801 802 while (msg_data_left(msg)) { 803 if (sk->sk_err) { 804 ret = -sk->sk_err; 805 goto send_end; 806 } 807 808 if (ctx->open_rec) 809 rec = ctx->open_rec; 810 else 811 rec = ctx->open_rec = tls_get_rec(sk); 812 if (!rec) { 813 ret = -ENOMEM; 814 goto send_end; 815 } 816 817 msg_pl = &rec->msg_plaintext; 818 msg_en = &rec->msg_encrypted; 819 820 orig_size = msg_pl->sg.size; 821 full_record = false; 822 try_to_copy = msg_data_left(msg); 823 record_room = tls_ctx->tx_max_payload_len - msg_pl->sg.size; 824 if (try_to_copy >= record_room) { 825 try_to_copy = record_room; 826 full_record = true; 827 } 828 829 required_size = msg_pl->sg.size + try_to_copy + 830 prot->overhead_size; 831 832 if (!sk_stream_memory_free(sk)) 833 goto wait_for_sndbuf; 834 835 /* open record may be full if we couldn't push it in the last sendmsg call */ 836 if (sk_msg_full(msg_pl)) { 837 full_record = true; 838 sk_msg_trim(sk, msg_en, 839 msg_pl->sg.size + prot->overhead_size); 840 goto copied; 841 } 842 843 alloc_encrypted: 844 ret = tls_alloc_encrypted_msg(sk, required_size); 845 if (ret) { 846 if (ret != -ENOSPC) 847 goto wait_for_memory; 848 849 /* Adjust try_to_copy according to the amount that was 850 * actually allocated. The difference is due 851 * to max sg elements limit 852 */ 853 try_to_copy -= required_size - msg_en->sg.size; 854 full_record = true; 855 } 856 857 if (try_to_copy && (msg->msg_flags & MSG_SPLICE_PAGES)) { 858 ret = tls_sw_sendmsg_splice(sk, msg, msg_pl, 859 try_to_copy, &copied); 860 if (ret < 0) 861 goto send_end; 862 tls_ctx->pending_open_record_frags = true; 863 864 if (sk_msg_full(msg_pl)) { 865 full_record = true; 866 sk_msg_trim(sk, msg_en, 867 msg_pl->sg.size + prot->overhead_size); 868 } 869 870 if (full_record || eor) 871 goto copied; 872 continue; 873 } 874 875 if (!is_kvec && (full_record || eor) && !async_capable) { 876 u32 first = msg_pl->sg.end; 877 878 ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter, 879 msg_pl, try_to_copy); 880 if (ret) 881 goto fallback_to_reg_send; 882 883 num_zc++; 884 copied += try_to_copy; 885 886 sk_msg_sg_copy_set(msg_pl, first); 887 ret = bpf_exec_tx_verdict(msg_pl, sk, 888 record_type, &copied, 889 msg->msg_flags); 890 if (ret) { 891 if (ret == -EINPROGRESS) 892 num_async++; 893 else if (ret == -ENOMEM) 894 goto wait_for_memory; 895 else if (ret != -EAGAIN) 896 goto send_end; 897 } 898 899 /* Transmit if any encryptions have completed */ 900 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { 901 cancel_delayed_work(&ctx->tx_work.work); 902 tls_tx_records(sk, msg->msg_flags); 903 } 904 905 continue; 906 fallback_to_reg_send: 907 sk_msg_trim(sk, msg_pl, orig_size); 908 } 909 910 required_size = msg_pl->sg.size + try_to_copy; 911 912 ret = tls_clone_plaintext_msg(sk, required_size); 913 if (ret) { 914 if (ret != -ENOSPC) 915 goto send_end; 916 917 /* Adjust try_to_copy according to the amount that was 918 * actually allocated. The difference is due 919 * to max sg elements limit 920 */ 921 try_to_copy -= required_size - msg_pl->sg.size; 922 full_record = true; 923 sk_msg_trim(sk, msg_en, 924 msg_pl->sg.size + prot->overhead_size); 925 } 926 927 if (try_to_copy) { 928 ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter, 929 msg_pl, try_to_copy); 930 if (ret < 0) 931 goto trim_sgl; 932 933 if (sk_msg_full(msg_pl)) { 934 full_record = true; 935 sk_msg_trim(sk, msg_en, 936 msg_pl->sg.size + prot->overhead_size); 937 } 938 } 939 940 /* Open records defined only if successfully copied, otherwise 941 * we would trim the sg but not reset the open record frags. 942 */ 943 tls_ctx->pending_open_record_frags = true; 944 copied += try_to_copy; 945 copied: 946 if (full_record || eor) { 947 ret = bpf_exec_tx_verdict(msg_pl, sk, 948 record_type, &copied, 949 msg->msg_flags); 950 if (ret) { 951 if (ret == -EINPROGRESS) 952 num_async++; 953 else if (ret == -ENOMEM) 954 goto wait_for_memory; 955 else if (ret != -EAGAIN) 956 goto send_end; 957 } 958 959 /* Transmit if any encryptions have completed */ 960 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { 961 cancel_delayed_work(&ctx->tx_work.work); 962 tls_tx_records(sk, msg->msg_flags); 963 } 964 } 965 966 continue; 967 968 wait_for_sndbuf: 969 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 970 wait_for_memory: 971 ret = sk_stream_wait_memory(sk, &timeo); 972 if (ret) { 973 trim_sgl: 974 if (ctx->open_rec) 975 tls_trim_both_msgs(sk, orig_size); 976 goto send_end; 977 } 978 979 if (ctx->open_rec && msg_en->sg.size < required_size) 980 goto alloc_encrypted; 981 } 982 983 send_end: 984 if (!num_async) { 985 goto end; 986 } else if (num_zc || eor) { 987 int err; 988 989 /* Wait for pending encryptions to get completed */ 990 err = tls_encrypt_async_wait(ctx); 991 if (err) { 992 ret = err; 993 copied = 0; 994 } 995 } 996 997 /* Transmit if any encryptions have completed */ 998 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { 999 cancel_delayed_work(&ctx->tx_work.work); 1000 tls_tx_records(sk, msg->msg_flags); 1001 } 1002 1003 end: 1004 ret = sk_stream_error(sk, msg->msg_flags, ret); 1005 return copied > 0 ? copied : ret; 1006 } 1007 1008 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) 1009 { 1010 struct tls_context *tls_ctx = tls_get_ctx(sk); 1011 int ret; 1012 1013 if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | 1014 MSG_CMSG_COMPAT | MSG_SPLICE_PAGES | MSG_EOR | 1015 MSG_SENDPAGE_NOPOLICY)) 1016 return -EOPNOTSUPP; 1017 1018 ret = mutex_lock_interruptible(&tls_ctx->tx_lock); 1019 if (ret) 1020 return ret; 1021 lock_sock(sk); 1022 ret = tls_sw_sendmsg_locked(sk, msg, size); 1023 release_sock(sk); 1024 mutex_unlock(&tls_ctx->tx_lock); 1025 return ret; 1026 } 1027 1028 /* 1029 * Handle unexpected EOF during splice without SPLICE_F_MORE set. 1030 */ 1031 void tls_sw_splice_eof(struct socket *sock) 1032 { 1033 struct sock *sk = sock->sk; 1034 struct tls_context *tls_ctx = tls_get_ctx(sk); 1035 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 1036 struct tls_rec *rec; 1037 struct sk_msg *msg_pl; 1038 ssize_t copied = 0; 1039 bool retrying = false; 1040 int ret = 0; 1041 1042 if (!ctx->open_rec) 1043 return; 1044 1045 mutex_lock(&tls_ctx->tx_lock); 1046 lock_sock(sk); 1047 1048 retry: 1049 /* same checks as in tls_sw_push_pending_record() */ 1050 rec = ctx->open_rec; 1051 if (!rec) 1052 goto unlock; 1053 1054 msg_pl = &rec->msg_plaintext; 1055 if (msg_pl->sg.size == 0) 1056 goto unlock; 1057 1058 /* Perform transmission. */ 1059 ret = bpf_exec_tx_verdict(msg_pl, sk, TLS_RECORD_TYPE_DATA, 1060 &copied, 0); 1061 switch (ret) { 1062 case 0: 1063 case -EAGAIN: 1064 if (retrying) 1065 goto unlock; 1066 retrying = true; 1067 goto retry; 1068 case -EINPROGRESS: 1069 break; 1070 default: 1071 goto unlock; 1072 } 1073 1074 /* Wait for pending encryptions to get completed */ 1075 if (tls_encrypt_async_wait(ctx)) 1076 goto unlock; 1077 1078 /* Transmit if any encryptions have completed */ 1079 if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { 1080 cancel_delayed_work(&ctx->tx_work.work); 1081 tls_tx_records(sk, 0); 1082 } 1083 1084 unlock: 1085 release_sock(sk); 1086 mutex_unlock(&tls_ctx->tx_lock); 1087 } 1088 1089 /* When has_copied is true the caller has already moved bytes to 1090 * userspace. Report sk_err but leave it set so the next read 1091 * surfaces it instead of a spurious EOF, otherwise sk_err is 1092 * consumed via sock_error(). 1093 */ 1094 static int 1095 tls_rx_rec_wait(struct sock *sk, bool nonblock, bool released, bool has_copied) 1096 { 1097 struct tls_context *tls_ctx = tls_get_ctx(sk); 1098 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1099 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1100 int ret = 0; 1101 long timeo; 1102 1103 /* a rekey is pending, let userspace deal with it */ 1104 if (unlikely(ctx->key_update_pending)) 1105 return -EKEYEXPIRED; 1106 1107 timeo = sock_rcvtimeo(sk, nonblock); 1108 1109 while (!tls_strp_msg_ready(ctx)) { 1110 if (sk->sk_err) { 1111 if (has_copied) 1112 return -READ_ONCE(sk->sk_err); 1113 return sock_error(sk); 1114 } 1115 1116 if (ret < 0) 1117 return ret; 1118 1119 if (sk_flush_backlog(sk)) 1120 released = true; 1121 if (!skb_queue_empty(&sk->sk_receive_queue)) { 1122 /* Defer notification to the exit point; this thread 1123 * will consume the record directly. 1124 */ 1125 tls_strp_check_rcv(&ctx->strp, false); 1126 if (tls_strp_msg_ready(ctx)) 1127 break; 1128 } 1129 1130 /* sk_flush_backlog() can run tcp_reset(), which sets 1131 * sk_err and then sk_shutdown via tcp_done(). Recheck 1132 * sk_err here so a connection abort surfaces as the 1133 * actual error rather than a clean EOF. 1134 */ 1135 if (sk->sk_err) { 1136 if (has_copied) 1137 return -READ_ONCE(sk->sk_err); 1138 return sock_error(sk); 1139 } 1140 if (sk->sk_shutdown & RCV_SHUTDOWN) 1141 return 0; 1142 1143 if (sock_flag(sk, SOCK_DONE)) 1144 return 0; 1145 1146 if (!timeo) 1147 return -EAGAIN; 1148 1149 released = true; 1150 add_wait_queue(sk_sleep(sk), &wait); 1151 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 1152 ret = sk_wait_event(sk, &timeo, 1153 tls_strp_msg_ready(ctx), &wait); 1154 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 1155 remove_wait_queue(sk_sleep(sk), &wait); 1156 1157 /* Handle signals */ 1158 if (signal_pending(current)) 1159 return sock_intr_errno(timeo); 1160 } 1161 1162 if (unlikely(!tls_strp_msg_load(&ctx->strp, released))) 1163 return tls_rx_rec_wait(sk, nonblock, false, has_copied); 1164 1165 return 1; 1166 } 1167 1168 static int tls_setup_from_iter(struct iov_iter *from, 1169 int length, int *pages_used, 1170 struct scatterlist *to, 1171 int to_max_pages) 1172 { 1173 int rc = 0, i = 0, num_elem = *pages_used, maxpages; 1174 struct page *pages[MAX_SKB_FRAGS]; 1175 unsigned int size = 0; 1176 ssize_t copied, use; 1177 size_t offset; 1178 1179 while (length > 0) { 1180 i = 0; 1181 maxpages = to_max_pages - num_elem; 1182 if (maxpages == 0) { 1183 rc = -EFAULT; 1184 goto out; 1185 } 1186 copied = iov_iter_get_pages2(from, pages, 1187 length, 1188 maxpages, &offset); 1189 if (copied <= 0) { 1190 rc = -EFAULT; 1191 goto out; 1192 } 1193 1194 length -= copied; 1195 size += copied; 1196 while (copied) { 1197 use = min_t(int, copied, PAGE_SIZE - offset); 1198 1199 sg_set_page(&to[num_elem], 1200 pages[i], use, offset); 1201 sg_unmark_end(&to[num_elem]); 1202 /* We do not uncharge memory from this API */ 1203 1204 offset = 0; 1205 copied -= use; 1206 1207 i++; 1208 num_elem++; 1209 } 1210 } 1211 /* Mark the end in the last sg entry if newly added */ 1212 if (num_elem > *pages_used) 1213 sg_mark_end(&to[num_elem - 1]); 1214 out: 1215 if (rc) 1216 iov_iter_revert(from, size); 1217 *pages_used = num_elem; 1218 1219 return rc; 1220 } 1221 1222 static struct sk_buff * 1223 tls_alloc_clrtxt_skb(struct sock *sk, struct sk_buff *skb, 1224 unsigned int full_len) 1225 { 1226 struct strp_msg *clr_rxm; 1227 struct sk_buff *clr_skb; 1228 int err; 1229 1230 clr_skb = alloc_skb_with_frags(0, full_len, TLS_PAGE_ORDER, 1231 &err, sk->sk_allocation); 1232 if (!clr_skb) 1233 return NULL; 1234 1235 skb_copy_header(clr_skb, skb); 1236 clr_skb->len = full_len; 1237 clr_skb->data_len = full_len; 1238 1239 clr_rxm = strp_msg(clr_skb); 1240 clr_rxm->offset = 0; 1241 1242 return clr_skb; 1243 } 1244 1245 /* Decrypt handlers 1246 * 1247 * tls_decrypt_sw() and tls_decrypt_device() are decrypt handlers. 1248 * They must transform the darg in/out argument are as follows: 1249 * | Input | Output 1250 * ------------------------------------------------------------------- 1251 * zc | Zero-copy decrypt allowed | Zero-copy performed 1252 * async | Async decrypt allowed | Async crypto used / in progress 1253 * skb | * | Output skb 1254 * 1255 * If ZC decryption was performed darg.skb will point to the input skb. 1256 */ 1257 1258 /* This function decrypts the input skb into either out_iov or in out_sg 1259 * or in skb buffers itself. The input parameter 'darg->zc' indicates if 1260 * zero-copy mode needs to be tried or not. With zero-copy mode, either 1261 * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are 1262 * NULL, then the decryption happens inside skb buffers itself, i.e. 1263 * zero-copy gets disabled and 'darg->zc' is updated. 1264 */ 1265 static int tls_decrypt_sg(struct sock *sk, struct iov_iter *out_iov, 1266 struct scatterlist *out_sg, 1267 struct tls_decrypt_arg *darg) 1268 { 1269 struct tls_context *tls_ctx = tls_get_ctx(sk); 1270 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1271 struct tls_prot_info *prot = &tls_ctx->prot_info; 1272 int n_sgin, n_sgout, aead_size, err, pages = 0; 1273 struct sk_buff *skb = tls_strp_msg(ctx); 1274 const struct strp_msg *rxm = strp_msg(skb); 1275 const struct tls_msg *tlm = tls_msg(skb); 1276 struct aead_request *aead_req; 1277 struct scatterlist *sgin = NULL; 1278 struct scatterlist *sgout = NULL; 1279 const int data_len = rxm->full_len - prot->overhead_size; 1280 int tail_pages = !!prot->tail_size; 1281 struct tls_decrypt_ctx *dctx; 1282 struct sk_buff *clear_skb; 1283 int iv_offset = 0; 1284 u8 *mem; 1285 1286 n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size, 1287 rxm->full_len - prot->prepend_size); 1288 if (n_sgin < 1) 1289 return n_sgin ?: -EBADMSG; 1290 1291 if (darg->zc && (out_iov || out_sg)) { 1292 clear_skb = NULL; 1293 1294 if (out_iov) 1295 n_sgout = 1 + tail_pages + 1296 iov_iter_npages_cap(out_iov, INT_MAX, data_len); 1297 else 1298 n_sgout = sg_nents(out_sg); 1299 } else { 1300 darg->zc = false; 1301 1302 clear_skb = tls_alloc_clrtxt_skb(sk, skb, rxm->full_len); 1303 if (!clear_skb) 1304 return -ENOMEM; 1305 1306 n_sgout = 1 + skb_shinfo(clear_skb)->nr_frags; 1307 } 1308 1309 /* Increment to accommodate AAD */ 1310 n_sgin = n_sgin + 1; 1311 1312 /* Allocate a single block of memory which contains 1313 * aead_req || tls_decrypt_ctx. 1314 * Both structs are variable length. 1315 */ 1316 aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv); 1317 aead_size = ALIGN(aead_size, __alignof__(*dctx)); 1318 mem = kmalloc(aead_size + struct_size(dctx, sg, size_add(n_sgin, n_sgout)), 1319 sk->sk_allocation); 1320 if (!mem) { 1321 err = -ENOMEM; 1322 goto exit_free_skb; 1323 } 1324 1325 /* Segment the allocated memory */ 1326 aead_req = (struct aead_request *)mem; 1327 dctx = (struct tls_decrypt_ctx *)(mem + aead_size); 1328 dctx->sk = sk; 1329 sgin = &dctx->sg[0]; 1330 sgout = &dctx->sg[n_sgin]; 1331 1332 /* For CCM based ciphers, first byte of nonce+iv is a constant */ 1333 switch (prot->cipher_type) { 1334 case TLS_CIPHER_AES_CCM_128: 1335 dctx->iv[0] = TLS_AES_CCM_IV_B0_BYTE; 1336 iv_offset = 1; 1337 break; 1338 case TLS_CIPHER_SM4_CCM: 1339 dctx->iv[0] = TLS_SM4_CCM_IV_B0_BYTE; 1340 iv_offset = 1; 1341 break; 1342 } 1343 1344 /* Prepare IV */ 1345 if (prot->version == TLS_1_3_VERSION || 1346 prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) { 1347 memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv, 1348 prot->iv_size + prot->salt_size); 1349 } else { 1350 err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE, 1351 &dctx->iv[iv_offset] + prot->salt_size, 1352 prot->iv_size); 1353 if (err < 0) 1354 goto exit_free; 1355 memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv, prot->salt_size); 1356 } 1357 tls_xor_iv_with_seq(prot, &dctx->iv[iv_offset], tls_ctx->rx.rec_seq); 1358 1359 /* Prepare AAD */ 1360 tls_make_aad(dctx->aad, rxm->full_len - prot->overhead_size + 1361 prot->tail_size, 1362 tls_ctx->rx.rec_seq, tlm->control, prot); 1363 1364 /* Prepare sgin */ 1365 sg_init_table(sgin, n_sgin); 1366 sg_set_buf(&sgin[0], dctx->aad, prot->aad_size); 1367 err = skb_to_sgvec(skb, &sgin[1], 1368 rxm->offset + prot->prepend_size, 1369 rxm->full_len - prot->prepend_size); 1370 if (err < 0) 1371 goto exit_free; 1372 1373 if (clear_skb) { 1374 sg_init_table(sgout, n_sgout); 1375 sg_set_buf(&sgout[0], dctx->aad, prot->aad_size); 1376 1377 err = skb_to_sgvec(clear_skb, &sgout[1], prot->prepend_size, 1378 data_len + prot->tail_size); 1379 if (err < 0) 1380 goto exit_free; 1381 } else if (out_iov) { 1382 sg_init_table(sgout, n_sgout); 1383 sg_set_buf(&sgout[0], dctx->aad, prot->aad_size); 1384 1385 err = tls_setup_from_iter(out_iov, data_len, &pages, &sgout[1], 1386 (n_sgout - 1 - tail_pages)); 1387 if (err < 0) 1388 goto exit_free_pages; 1389 1390 if (prot->tail_size) { 1391 sg_unmark_end(&sgout[pages]); 1392 sg_set_buf(&sgout[pages + 1], &dctx->tail, 1393 prot->tail_size); 1394 sg_mark_end(&sgout[pages + 1]); 1395 } 1396 } else if (out_sg) { 1397 memcpy(sgout, out_sg, n_sgout * sizeof(*sgout)); 1398 } 1399 dctx->free_sgout = !!pages; 1400 1401 /* Prepare and submit AEAD request */ 1402 err = tls_do_decryption(sk, sgin, sgout, dctx->iv, 1403 data_len + prot->tail_size, aead_req, darg); 1404 if (err) { 1405 if (darg->async_done) 1406 goto exit_free_skb; 1407 goto exit_free_pages; 1408 } 1409 1410 darg->skb = clear_skb ?: tls_strp_msg(ctx); 1411 clear_skb = NULL; 1412 1413 if (unlikely(darg->async)) { 1414 err = tls_strp_msg_hold(&ctx->strp, &ctx->async_hold); 1415 if (err) { 1416 err = tls_decrypt_async_wait(ctx); 1417 darg->async = false; 1418 } 1419 return err; 1420 } 1421 1422 if (unlikely(darg->async_done)) 1423 return 0; 1424 1425 if (prot->tail_size) 1426 darg->tail = dctx->tail; 1427 1428 exit_free_pages: 1429 /* Release the pages in case iov was mapped to pages */ 1430 for (; pages > 0; pages--) 1431 put_page(sg_page(&sgout[pages])); 1432 exit_free: 1433 kfree(mem); 1434 exit_free_skb: 1435 consume_skb(clear_skb); 1436 return err; 1437 } 1438 1439 static int 1440 tls_decrypt_sw(struct sock *sk, struct tls_context *tls_ctx, 1441 struct msghdr *msg, struct tls_decrypt_arg *darg) 1442 { 1443 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1444 struct tls_prot_info *prot = &tls_ctx->prot_info; 1445 struct strp_msg *rxm; 1446 int pad, err; 1447 1448 err = tls_decrypt_sg(sk, &msg->msg_iter, NULL, darg); 1449 if (err < 0) { 1450 if (err == -EBADMSG) 1451 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR); 1452 return err; 1453 } 1454 /* keep going even for ->async, the code below is TLS 1.3 */ 1455 1456 /* If opportunistic TLS 1.3 ZC failed retry without ZC */ 1457 if (unlikely(darg->zc && prot->version == TLS_1_3_VERSION && 1458 darg->tail != TLS_RECORD_TYPE_DATA)) { 1459 iov_iter_revert(&msg->msg_iter, strp_msg(darg->skb)->full_len - 1460 prot->overhead_size); 1461 darg->zc = false; 1462 if (!darg->tail) 1463 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXNOPADVIOL); 1464 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTRETRY); 1465 return tls_decrypt_sw(sk, tls_ctx, msg, darg); 1466 } 1467 1468 pad = tls_padding_length(prot, darg->skb, darg); 1469 if (pad < 0) { 1470 if (darg->skb != tls_strp_msg(ctx)) 1471 consume_skb(darg->skb); 1472 return pad; 1473 } 1474 1475 rxm = strp_msg(darg->skb); 1476 rxm->full_len -= pad; 1477 1478 return 0; 1479 } 1480 1481 static int 1482 tls_decrypt_device(struct sock *sk, struct msghdr *msg, 1483 struct tls_context *tls_ctx, struct tls_decrypt_arg *darg) 1484 { 1485 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1486 struct tls_prot_info *prot = &tls_ctx->prot_info; 1487 struct strp_msg *rxm; 1488 int pad, err; 1489 1490 if (tls_ctx->rx_conf != TLS_HW) 1491 return 0; 1492 1493 err = tls_device_decrypted(sk, tls_ctx); 1494 if (err <= 0) 1495 return err; 1496 1497 pad = tls_padding_length(prot, tls_strp_msg(ctx), darg); 1498 if (pad < 0) 1499 return pad; 1500 1501 darg->async = false; 1502 darg->skb = tls_strp_msg(ctx); 1503 /* ->zc downgrade check, in case TLS 1.3 gets here */ 1504 darg->zc &= !(prot->version == TLS_1_3_VERSION && 1505 tls_msg(darg->skb)->control != TLS_RECORD_TYPE_DATA); 1506 1507 rxm = strp_msg(darg->skb); 1508 rxm->full_len -= pad; 1509 1510 if (!darg->zc) { 1511 /* Non-ZC case needs a real skb */ 1512 darg->skb = tls_strp_msg_detach(ctx); 1513 if (!darg->skb) 1514 return -ENOMEM; 1515 } else { 1516 unsigned int off, len; 1517 1518 /* In ZC case nobody cares about the output skb. 1519 * Just copy the data here. Note the skb is not fully trimmed. 1520 */ 1521 off = rxm->offset + prot->prepend_size; 1522 len = rxm->full_len - prot->overhead_size; 1523 1524 err = skb_copy_datagram_msg(darg->skb, off, msg, len); 1525 if (err) 1526 return err; 1527 } 1528 return 1; 1529 } 1530 1531 static int tls_check_pending_rekey(struct sock *sk, struct tls_context *ctx, 1532 struct sk_buff *skb) 1533 { 1534 const struct strp_msg *rxm = strp_msg(skb); 1535 const struct tls_msg *tlm = tls_msg(skb); 1536 char hs_type; 1537 int err; 1538 1539 if (likely(tlm->control != TLS_RECORD_TYPE_HANDSHAKE)) 1540 return 0; 1541 1542 if (rxm->full_len < 1) 1543 return 0; 1544 1545 err = skb_copy_bits(skb, rxm->offset, &hs_type, 1); 1546 if (err < 0) { 1547 DEBUG_NET_WARN_ON_ONCE(1); 1548 return err; 1549 } 1550 1551 if (hs_type == TLS_HANDSHAKE_KEYUPDATE) { 1552 struct tls_sw_context_rx *rx_ctx = ctx->priv_ctx_rx; 1553 1554 WRITE_ONCE(rx_ctx->key_update_pending, true); 1555 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXREKEYRECEIVED); 1556 } 1557 1558 return 0; 1559 } 1560 1561 /* On decrypt failure the connection is aborted (sk_err set) before 1562 * returning a negative errno. 1563 */ 1564 static int tls_rx_one_record(struct sock *sk, struct msghdr *msg, 1565 struct tls_decrypt_arg *darg) 1566 { 1567 struct tls_context *tls_ctx = tls_get_ctx(sk); 1568 struct tls_prot_info *prot = &tls_ctx->prot_info; 1569 struct strp_msg *rxm; 1570 int err; 1571 1572 err = tls_decrypt_device(sk, msg, tls_ctx, darg); 1573 if (!err) 1574 err = tls_decrypt_sw(sk, tls_ctx, msg, darg); 1575 if (err < 0) { 1576 tls_err_abort(sk, -EBADMSG); 1577 return err; 1578 } 1579 1580 rxm = strp_msg(darg->skb); 1581 rxm->offset += prot->prepend_size; 1582 rxm->full_len -= prot->overhead_size; 1583 tls_advance_record_sn(sk, prot, &tls_ctx->rx); 1584 1585 return tls_check_pending_rekey(sk, tls_ctx, darg->skb); 1586 } 1587 1588 int decrypt_skb(struct sock *sk, struct scatterlist *sgout) 1589 { 1590 struct tls_decrypt_arg darg = { .zc = true, }; 1591 1592 return tls_decrypt_sg(sk, NULL, sgout, &darg); 1593 } 1594 1595 /* All records returned from a recvmsg() call must have the same type. 1596 * 0 is not a valid content type. Use it as "no type reported, yet". 1597 */ 1598 static int tls_record_content_type(struct msghdr *msg, struct tls_msg *tlm, 1599 u8 *control) 1600 { 1601 int err; 1602 1603 if (!*control) { 1604 *control = tlm->control; 1605 if (!*control) 1606 return -EBADMSG; 1607 1608 err = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE, 1609 sizeof(*control), control); 1610 if (*control != TLS_RECORD_TYPE_DATA) { 1611 if (err || msg->msg_flags & MSG_CTRUNC) 1612 return -EIO; 1613 } 1614 } else if (*control != tlm->control) { 1615 return 0; 1616 } 1617 1618 return 1; 1619 } 1620 1621 /* The deferred announce is fired once on reader exit by 1622 * tls_rx_reader_release(). 1623 */ 1624 static void tls_rx_rec_done(struct tls_sw_context_rx *ctx) 1625 { 1626 tls_strp_msg_consume(&ctx->strp); 1627 tls_strp_check_rcv(&ctx->strp, false); 1628 } 1629 1630 /* This function traverses the rx_list in tls receive context to copies the 1631 * decrypted records into the buffer provided by caller zero copy is not 1632 * true. Further, the records are removed from the rx_list if it is not a peek 1633 * case and the record has been consumed completely. 1634 */ 1635 static int process_rx_list(struct tls_sw_context_rx *ctx, 1636 struct msghdr *msg, 1637 u8 *control, 1638 size_t skip, 1639 size_t len, 1640 bool is_peek, 1641 bool *more) 1642 { 1643 struct sk_buff *skb = skb_peek(&ctx->rx_list); 1644 struct tls_msg *tlm; 1645 ssize_t copied = 0; 1646 int err; 1647 1648 while (skip && skb) { 1649 struct strp_msg *rxm = strp_msg(skb); 1650 tlm = tls_msg(skb); 1651 1652 err = tls_record_content_type(msg, tlm, control); 1653 if (err <= 0) 1654 goto more; 1655 1656 if (skip < rxm->full_len) 1657 break; 1658 1659 skip = skip - rxm->full_len; 1660 skb = skb_peek_next(skb, &ctx->rx_list); 1661 } 1662 1663 while (len && skb) { 1664 struct sk_buff *next_skb; 1665 struct strp_msg *rxm = strp_msg(skb); 1666 int chunk = min_t(unsigned int, rxm->full_len - skip, len); 1667 1668 tlm = tls_msg(skb); 1669 1670 err = tls_record_content_type(msg, tlm, control); 1671 if (err <= 0) 1672 goto more; 1673 1674 err = skb_copy_datagram_msg(skb, rxm->offset + skip, 1675 msg, chunk); 1676 if (err < 0) 1677 goto more; 1678 1679 len = len - chunk; 1680 copied = copied + chunk; 1681 1682 /* Consume the data from record if it is non-peek case*/ 1683 if (!is_peek) { 1684 rxm->offset = rxm->offset + chunk; 1685 rxm->full_len = rxm->full_len - chunk; 1686 1687 /* Return if there is unconsumed data in the record */ 1688 if (rxm->full_len - skip) 1689 break; 1690 } 1691 1692 /* The remaining skip-bytes must lie in 1st record in rx_list. 1693 * So from the 2nd record, 'skip' should be 0. 1694 */ 1695 skip = 0; 1696 1697 if (msg) 1698 msg->msg_flags |= MSG_EOR; 1699 1700 next_skb = skb_peek_next(skb, &ctx->rx_list); 1701 1702 if (!is_peek) { 1703 __skb_unlink(skb, &ctx->rx_list); 1704 consume_skb(skb); 1705 } 1706 1707 skb = next_skb; 1708 } 1709 err = 0; 1710 1711 out: 1712 return copied ? : err; 1713 more: 1714 if (more) 1715 *more = true; 1716 goto out; 1717 } 1718 1719 static bool 1720 tls_read_flush_backlog(struct sock *sk, struct tls_prot_info *prot, 1721 size_t len_left, size_t decrypted, ssize_t done, 1722 size_t *flushed_at) 1723 { 1724 size_t max_rec; 1725 1726 if (len_left <= decrypted) 1727 return false; 1728 1729 max_rec = prot->overhead_size - prot->tail_size + TLS_MAX_PAYLOAD_SIZE; 1730 if (done - *flushed_at < SZ_128K && tcp_inq(sk) > max_rec) 1731 return false; 1732 1733 *flushed_at = done; 1734 return sk_flush_backlog(sk); 1735 } 1736 1737 static int tls_rx_reader_acquire(struct sock *sk, struct tls_sw_context_rx *ctx, 1738 bool nonblock) 1739 { 1740 long timeo; 1741 int ret; 1742 1743 timeo = sock_rcvtimeo(sk, nonblock); 1744 1745 while (unlikely(ctx->reader_present)) { 1746 DEFINE_WAIT_FUNC(wait, woken_wake_function); 1747 1748 ctx->reader_contended = 1; 1749 1750 add_wait_queue(&ctx->wq, &wait); 1751 ret = sk_wait_event(sk, &timeo, 1752 !READ_ONCE(ctx->reader_present), &wait); 1753 remove_wait_queue(&ctx->wq, &wait); 1754 1755 if (timeo <= 0) 1756 return -EAGAIN; 1757 if (signal_pending(current)) 1758 return sock_intr_errno(timeo); 1759 if (ret < 0) 1760 return ret; 1761 } 1762 1763 WRITE_ONCE(ctx->reader_present, 1); 1764 1765 return 0; 1766 } 1767 1768 static int tls_rx_reader_lock(struct sock *sk, struct tls_sw_context_rx *ctx, 1769 bool nonblock) 1770 { 1771 int err; 1772 1773 lock_sock(sk); 1774 err = tls_rx_reader_acquire(sk, ctx, nonblock); 1775 if (err) 1776 release_sock(sk); 1777 return err; 1778 } 1779 1780 static void tls_rx_reader_release(struct sock *sk, struct tls_sw_context_rx *ctx) 1781 { 1782 /* Fire any deferred announce once per reader so that a record 1783 * parsed but not yet announced becomes visible to the next 1784 * reader. The call is idempotent through msg_announced. 1785 */ 1786 tls_rx_msg_maybe_announce(&ctx->strp); 1787 1788 if (unlikely(ctx->reader_contended)) { 1789 if (wq_has_sleeper(&ctx->wq)) 1790 wake_up(&ctx->wq); 1791 else 1792 ctx->reader_contended = 0; 1793 1794 WARN_ON_ONCE(!ctx->reader_present); 1795 } 1796 1797 WRITE_ONCE(ctx->reader_present, 0); 1798 } 1799 1800 static void tls_rx_reader_unlock(struct sock *sk, struct tls_sw_context_rx *ctx) 1801 { 1802 tls_rx_reader_release(sk, ctx); 1803 release_sock(sk); 1804 } 1805 1806 int tls_sw_recvmsg(struct sock *sk, 1807 struct msghdr *msg, 1808 size_t len, 1809 int flags) 1810 { 1811 struct tls_context *tls_ctx = tls_get_ctx(sk); 1812 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 1813 struct tls_prot_info *prot = &tls_ctx->prot_info; 1814 ssize_t decrypted = 0, async_copy_bytes = 0; 1815 unsigned char control = 0; 1816 size_t flushed_at = 0; 1817 struct strp_msg *rxm; 1818 struct tls_msg *tlm; 1819 ssize_t copied = 0; 1820 ssize_t peeked = 0; 1821 bool async = false; 1822 int target, err; 1823 bool is_kvec = iov_iter_is_kvec(&msg->msg_iter); 1824 bool is_peek = flags & MSG_PEEK; 1825 bool rx_more = false; 1826 bool released = true; 1827 bool zc_capable; 1828 1829 if (unlikely(flags & MSG_ERRQUEUE)) 1830 return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR); 1831 1832 err = tls_rx_reader_lock(sk, ctx, flags & MSG_DONTWAIT); 1833 if (err < 0) 1834 return err; 1835 1836 /* If crypto failed the connection is broken */ 1837 err = ctx->async_wait.err; 1838 if (err) 1839 goto end; 1840 1841 /* Process pending decrypted records. It must be non-zero-copy */ 1842 err = process_rx_list(ctx, msg, &control, 0, len, is_peek, &rx_more); 1843 if (err < 0) 1844 goto end; 1845 1846 /* process_rx_list() will set @control if it processed any records */ 1847 copied = err; 1848 if (len <= copied || rx_more || 1849 (control && control != TLS_RECORD_TYPE_DATA)) 1850 goto end; 1851 1852 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); 1853 len = len - copied; 1854 1855 zc_capable = !is_kvec && !is_peek && ctx->zc_capable; 1856 decrypted = 0; 1857 while (len && (decrypted + copied < target || tls_strp_msg_ready(ctx))) { 1858 struct tls_decrypt_arg darg; 1859 int to_decrypt, chunk; 1860 1861 err = tls_rx_rec_wait(sk, flags & MSG_DONTWAIT, 1862 released, !!(decrypted + copied)); 1863 if (err <= 0) 1864 goto recv_end; 1865 1866 memset(&darg.inargs, 0, sizeof(darg.inargs)); 1867 1868 rxm = strp_msg(tls_strp_msg(ctx)); 1869 tlm = tls_msg(tls_strp_msg(ctx)); 1870 1871 to_decrypt = rxm->full_len - prot->overhead_size; 1872 1873 if (zc_capable && to_decrypt <= len && 1874 tlm->control == TLS_RECORD_TYPE_DATA) 1875 darg.zc = true; 1876 1877 /* Do not use async mode if record is non-data */ 1878 if (tlm->control == TLS_RECORD_TYPE_DATA) 1879 darg.async = ctx->async_capable; 1880 else 1881 darg.async = false; 1882 1883 err = tls_rx_one_record(sk, msg, &darg); 1884 if (err < 0) 1885 goto recv_end; 1886 1887 async |= darg.async; 1888 1889 /* If the type of records being processed is not known yet, 1890 * set it to record type just dequeued. If it is already known, 1891 * but does not match the record type just dequeued, go to end. 1892 * We always get record type here since for tls1.2, record type 1893 * is known just after record is dequeued from stream parser. 1894 * For tls1.3, we disable async. 1895 */ 1896 err = tls_record_content_type(msg, tls_msg(darg.skb), &control); 1897 if (err <= 0) { 1898 DEBUG_NET_WARN_ON_ONCE(darg.zc); 1899 tls_rx_rec_done(ctx); 1900 put_on_rx_list_err: 1901 __skb_queue_tail(&ctx->rx_list, darg.skb); 1902 goto recv_end; 1903 } 1904 1905 /* periodically flush backlog, and feed strparser */ 1906 released = tls_read_flush_backlog(sk, prot, len, to_decrypt, 1907 decrypted + copied, 1908 &flushed_at); 1909 1910 /* TLS 1.3 may have updated the length by more than overhead */ 1911 rxm = strp_msg(darg.skb); 1912 chunk = rxm->full_len; 1913 tls_rx_rec_done(ctx); 1914 1915 if (!darg.zc) { 1916 bool partially_consumed = chunk > len; 1917 struct sk_buff *skb = darg.skb; 1918 1919 DEBUG_NET_WARN_ON_ONCE(darg.skb == ctx->strp.anchor); 1920 1921 if (async) { 1922 /* TLS 1.2-only, to_decrypt must be text len */ 1923 chunk = min_t(int, to_decrypt, len); 1924 async_copy_bytes += chunk; 1925 put_on_rx_list: 1926 decrypted += chunk; 1927 len -= chunk; 1928 __skb_queue_tail(&ctx->rx_list, skb); 1929 if (unlikely(control != TLS_RECORD_TYPE_DATA)) 1930 break; 1931 continue; 1932 } 1933 1934 if (partially_consumed) 1935 chunk = len; 1936 1937 err = skb_copy_datagram_msg(skb, rxm->offset, 1938 msg, chunk); 1939 if (err < 0) 1940 goto put_on_rx_list_err; 1941 1942 if (is_peek) { 1943 peeked += chunk; 1944 goto put_on_rx_list; 1945 } 1946 1947 if (partially_consumed) { 1948 rxm->offset += chunk; 1949 rxm->full_len -= chunk; 1950 goto put_on_rx_list; 1951 } 1952 1953 consume_skb(skb); 1954 } 1955 1956 decrypted += chunk; 1957 len -= chunk; 1958 1959 /* Return full control message to userspace before trying 1960 * to parse another message type 1961 */ 1962 msg->msg_flags |= MSG_EOR; 1963 if (control != TLS_RECORD_TYPE_DATA) 1964 break; 1965 } 1966 1967 recv_end: 1968 if (async) { 1969 int ret; 1970 1971 /* Wait for all previously submitted records to be decrypted */ 1972 ret = tls_decrypt_async_wait(ctx); 1973 1974 if (ret) { 1975 if (err >= 0 || err == -EINPROGRESS) 1976 err = ret; 1977 goto end; 1978 } 1979 1980 /* Drain records from the rx_list & copy if required */ 1981 if (is_peek) 1982 err = process_rx_list(ctx, msg, &control, copied + peeked, 1983 decrypted - peeked, is_peek, NULL); 1984 else 1985 err = process_rx_list(ctx, msg, &control, 0, 1986 async_copy_bytes, is_peek, NULL); 1987 1988 /* we could have copied less than we wanted, and possibly nothing */ 1989 decrypted += max(err, 0) - async_copy_bytes; 1990 } 1991 1992 copied += decrypted; 1993 1994 end: 1995 tls_rx_reader_unlock(sk, ctx); 1996 return copied ? : err; 1997 } 1998 1999 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, 2000 struct pipe_inode_info *pipe, 2001 size_t len, unsigned int flags) 2002 { 2003 struct tls_context *tls_ctx = tls_get_ctx(sock->sk); 2004 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 2005 struct strp_msg *rxm = NULL; 2006 struct sock *sk = sock->sk; 2007 struct tls_msg *tlm; 2008 struct sk_buff *skb; 2009 ssize_t copied = 0; 2010 int chunk; 2011 int err; 2012 2013 err = tls_rx_reader_lock(sk, ctx, flags & SPLICE_F_NONBLOCK); 2014 if (err < 0) 2015 return err; 2016 2017 /* If crypto failed the connection is broken */ 2018 err = ctx->async_wait.err; 2019 if (err) 2020 goto splice_read_end; 2021 2022 if (!skb_queue_empty(&ctx->rx_list)) { 2023 skb = __skb_dequeue(&ctx->rx_list); 2024 } else { 2025 struct tls_decrypt_arg darg; 2026 2027 err = tls_rx_rec_wait(sk, flags & SPLICE_F_NONBLOCK, 2028 true, false); 2029 if (err <= 0) 2030 goto splice_read_end; 2031 2032 memset(&darg.inargs, 0, sizeof(darg.inargs)); 2033 2034 err = tls_rx_one_record(sk, NULL, &darg); 2035 if (err < 0) 2036 goto splice_read_end; 2037 2038 tls_rx_rec_done(ctx); 2039 skb = darg.skb; 2040 } 2041 2042 rxm = strp_msg(skb); 2043 tlm = tls_msg(skb); 2044 2045 /* splice does not support reading control messages */ 2046 if (tlm->control != TLS_RECORD_TYPE_DATA) { 2047 err = -EINVAL; 2048 goto splice_requeue; 2049 } 2050 2051 chunk = min_t(unsigned int, rxm->full_len, len); 2052 copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags); 2053 if (copied < 0) 2054 goto splice_requeue; 2055 2056 if (copied < rxm->full_len) { 2057 rxm->offset += copied; 2058 rxm->full_len -= copied; 2059 goto splice_requeue; 2060 } 2061 2062 consume_skb(skb); 2063 2064 splice_read_end: 2065 tls_rx_reader_unlock(sk, ctx); 2066 return copied ? : err; 2067 2068 splice_requeue: 2069 __skb_queue_head(&ctx->rx_list, skb); 2070 goto splice_read_end; 2071 } 2072 2073 int tls_sw_read_sock(struct sock *sk, read_descriptor_t *desc, 2074 sk_read_actor_t read_actor) 2075 { 2076 struct tls_context *tls_ctx = tls_get_ctx(sk); 2077 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 2078 struct tls_prot_info *prot = &tls_ctx->prot_info; 2079 struct strp_msg *rxm = NULL; 2080 struct sk_buff *skb = NULL; 2081 struct sk_psock *psock; 2082 size_t flushed_at = 0; 2083 bool released = true; 2084 struct tls_msg *tlm; 2085 ssize_t copied = 0; 2086 ssize_t decrypted; 2087 int err, used; 2088 2089 psock = sk_psock_get(sk); 2090 if (psock) { 2091 sk_psock_put(sk, psock); 2092 return -EINVAL; 2093 } 2094 err = tls_rx_reader_acquire(sk, ctx, true); 2095 if (err < 0) 2096 return err; 2097 2098 /* If crypto failed the connection is broken */ 2099 err = ctx->async_wait.err; 2100 if (err) 2101 goto read_sock_end; 2102 2103 decrypted = 0; 2104 while (desc->count) { 2105 if (!skb_queue_empty(&ctx->rx_list)) { 2106 skb = __skb_dequeue(&ctx->rx_list); 2107 rxm = strp_msg(skb); 2108 tlm = tls_msg(skb); 2109 } else { 2110 struct tls_decrypt_arg darg; 2111 2112 err = tls_rx_rec_wait(sk, true, released, !!copied); 2113 if (err <= 0) 2114 goto read_sock_end; 2115 2116 memset(&darg.inargs, 0, sizeof(darg.inargs)); 2117 2118 err = tls_rx_one_record(sk, NULL, &darg); 2119 if (err < 0) 2120 goto read_sock_end; 2121 2122 released = tls_read_flush_backlog(sk, prot, INT_MAX, 2123 0, decrypted, 2124 &flushed_at); 2125 skb = darg.skb; 2126 rxm = strp_msg(skb); 2127 tlm = tls_msg(skb); 2128 decrypted += rxm->full_len; 2129 2130 tls_rx_rec_done(ctx); 2131 } 2132 2133 /* read_sock does not support reading control messages */ 2134 if (tlm->control != TLS_RECORD_TYPE_DATA) { 2135 err = -EINVAL; 2136 goto read_sock_requeue; 2137 } 2138 2139 /* An empty data record (legal in TLS 1.3) gives a zero 2140 * read_actor return, indistinguishable from the consumer 2141 * stalling; the used <= 0 path would requeue it at the 2142 * head of rx_list and block all later records. Consume it 2143 * here instead. 2144 */ 2145 if (rxm->full_len == 0) { 2146 consume_skb(skb); 2147 continue; 2148 } 2149 2150 used = read_actor(desc, skb, rxm->offset, rxm->full_len); 2151 if (used <= 0) { 2152 if (!copied) 2153 err = used; 2154 goto read_sock_requeue; 2155 } 2156 copied += used; 2157 if (used < rxm->full_len) { 2158 rxm->offset += used; 2159 rxm->full_len -= used; 2160 __skb_queue_head(&ctx->rx_list, skb); 2161 } else { 2162 consume_skb(skb); 2163 } 2164 } 2165 2166 read_sock_end: 2167 tls_rx_reader_release(sk, ctx); 2168 return copied ? : err; 2169 2170 read_sock_requeue: 2171 __skb_queue_head(&ctx->rx_list, skb); 2172 goto read_sock_end; 2173 } 2174 2175 bool tls_sw_sock_is_readable(struct sock *sk) 2176 { 2177 struct tls_context *tls_ctx = tls_get_ctx(sk); 2178 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 2179 2180 return tls_strp_msg_ready(ctx) || 2181 !skb_queue_empty(&ctx->rx_list); 2182 } 2183 2184 int tls_rx_msg_size(struct tls_strparser *strp, struct sk_buff *skb) 2185 { 2186 struct tls_context *tls_ctx = tls_get_ctx(strp->sk); 2187 struct tls_prot_info *prot = &tls_ctx->prot_info; 2188 char header[TLS_HEADER_SIZE + TLS_MAX_IV_SIZE]; 2189 size_t cipher_overhead; 2190 size_t data_len = 0; 2191 int ret; 2192 2193 /* Verify that we have a full TLS header, or wait for more data */ 2194 if (strp->stm.offset + prot->prepend_size > skb->len) 2195 return 0; 2196 2197 /* Sanity-check size of on-stack buffer. */ 2198 if (WARN_ON(prot->prepend_size > sizeof(header))) { 2199 ret = -EINVAL; 2200 goto read_failure; 2201 } 2202 2203 /* Linearize header to local buffer */ 2204 ret = skb_copy_bits(skb, strp->stm.offset, header, prot->prepend_size); 2205 if (ret < 0) 2206 goto read_failure; 2207 2208 strp->mark = header[0]; 2209 2210 data_len = ((header[4] & 0xFF) | (header[3] << 8)); 2211 2212 cipher_overhead = prot->tag_size; 2213 if (prot->version != TLS_1_3_VERSION && 2214 prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305) 2215 cipher_overhead += prot->iv_size; 2216 2217 if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead + 2218 prot->tail_size) { 2219 ret = -EMSGSIZE; 2220 goto read_failure; 2221 } 2222 if (data_len < cipher_overhead) { 2223 ret = -EBADMSG; 2224 goto read_failure; 2225 } 2226 2227 /* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */ 2228 if (header[1] != TLS_1_2_VERSION_MINOR || 2229 header[2] != TLS_1_2_VERSION_MAJOR) { 2230 ret = -EINVAL; 2231 goto read_failure; 2232 } 2233 2234 tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE, 2235 TCP_SKB_CB(skb)->seq + strp->stm.offset); 2236 return data_len + TLS_HEADER_SIZE; 2237 2238 read_failure: 2239 tls_strp_abort_strp(strp, ret); 2240 return ret; 2241 } 2242 2243 /* Fire saved_data_ready() at most once per parsed record. The 2244 * msg_announced bit is cleared by tls_strp_msg_consume() when the 2245 * record is consumed, arming the next announcement. 2246 */ 2247 void tls_rx_msg_maybe_announce(struct tls_strparser *strp) 2248 { 2249 struct tls_sw_context_rx *ctx; 2250 2251 if (!READ_ONCE(strp->msg_ready) || strp->msg_announced) 2252 return; 2253 strp->msg_announced = 1; 2254 2255 ctx = container_of(strp, struct tls_sw_context_rx, strp); 2256 ctx->saved_data_ready(strp->sk); 2257 } 2258 2259 static void tls_data_ready(struct sock *sk) 2260 { 2261 struct tls_context *tls_ctx = tls_get_ctx(sk); 2262 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 2263 gfp_t alloc_save; 2264 2265 trace_sk_data_ready(sk); 2266 2267 alloc_save = sk->sk_allocation; 2268 sk->sk_allocation = GFP_ATOMIC; 2269 tls_strp_data_ready(&ctx->strp); 2270 sk->sk_allocation = alloc_save; 2271 } 2272 2273 void tls_sw_cancel_work_tx(struct tls_context *tls_ctx) 2274 { 2275 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 2276 2277 set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask); 2278 set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask); 2279 disable_delayed_work_sync(&ctx->tx_work.work); 2280 } 2281 2282 void tls_sw_release_resources_tx(struct sock *sk) 2283 { 2284 struct tls_context *tls_ctx = tls_get_ctx(sk); 2285 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 2286 struct tls_rec *rec, *tmp; 2287 2288 /* Wait for any pending async encryptions to complete */ 2289 tls_encrypt_async_wait(ctx); 2290 2291 tls_tx_records(sk, -1); 2292 2293 /* Free up un-sent records in tx_list. First, free 2294 * the partially sent record if any at head of tx_list. 2295 */ 2296 if (tls_ctx->partially_sent_record) { 2297 tls_free_partial_record(sk, tls_ctx); 2298 rec = list_first_entry(&ctx->tx_list, 2299 struct tls_rec, list); 2300 list_del(&rec->list); 2301 sk_msg_free(sk, &rec->msg_plaintext); 2302 kfree(rec); 2303 } 2304 2305 list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) { 2306 list_del(&rec->list); 2307 sk_msg_free(sk, &rec->msg_encrypted); 2308 sk_msg_free(sk, &rec->msg_plaintext); 2309 kfree(rec); 2310 } 2311 2312 crypto_free_aead(ctx->aead_send); 2313 tls_free_open_rec(sk); 2314 } 2315 2316 void tls_sw_free_ctx_tx(struct tls_context *tls_ctx) 2317 { 2318 struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); 2319 2320 kfree(ctx); 2321 } 2322 2323 void tls_sw_release_resources_rx(struct sock *sk) 2324 { 2325 struct tls_context *tls_ctx = tls_get_ctx(sk); 2326 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 2327 2328 if (ctx->aead_recv) { 2329 __skb_queue_purge(&ctx->rx_list); 2330 crypto_free_aead(ctx->aead_recv); 2331 tls_strp_stop(&ctx->strp); 2332 /* If tls_sw_strparser_arm() was not called (cleanup paths) 2333 * we still want to tls_strp_stop(), but sk->sk_data_ready was 2334 * never swapped. 2335 */ 2336 if (ctx->saved_data_ready) { 2337 write_lock_bh(&sk->sk_callback_lock); 2338 sk->sk_data_ready = ctx->saved_data_ready; 2339 write_unlock_bh(&sk->sk_callback_lock); 2340 } 2341 } 2342 } 2343 2344 void tls_sw_strparser_done(struct tls_context *tls_ctx) 2345 { 2346 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 2347 2348 tls_strp_done(&ctx->strp); 2349 } 2350 2351 void tls_sw_free_ctx_rx(struct tls_context *tls_ctx) 2352 { 2353 struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); 2354 2355 kfree(ctx); 2356 } 2357 2358 void tls_sw_free_resources_rx(struct sock *sk) 2359 { 2360 struct tls_context *tls_ctx = tls_get_ctx(sk); 2361 struct tls_sw_context_rx *ctx; 2362 2363 ctx = tls_sw_ctx_rx(tls_ctx); 2364 2365 tls_sw_release_resources_rx(sk); 2366 __tls_strp_done(&ctx->strp); 2367 tls_sw_free_ctx_rx(tls_ctx); 2368 } 2369 2370 /* The work handler to transmitt the encrypted records in tx_list */ 2371 static void tx_work_handler(struct work_struct *work) 2372 { 2373 struct delayed_work *delayed_work = to_delayed_work(work); 2374 struct tx_work *tx_work = container_of(delayed_work, 2375 struct tx_work, work); 2376 struct sock *sk = tx_work->sk; 2377 struct tls_context *tls_ctx = tls_get_ctx(sk); 2378 struct tls_sw_context_tx *ctx; 2379 2380 if (unlikely(!tls_ctx)) 2381 return; 2382 2383 ctx = tls_sw_ctx_tx(tls_ctx); 2384 if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask)) 2385 return; 2386 2387 if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) 2388 return; 2389 2390 if (mutex_trylock(&tls_ctx->tx_lock)) { 2391 lock_sock(sk); 2392 tls_tx_records(sk, -1); 2393 release_sock(sk); 2394 mutex_unlock(&tls_ctx->tx_lock); 2395 } else if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { 2396 /* Someone is holding the tx_lock, they will likely run Tx 2397 * and cancel the work on their way out of the lock section. 2398 * Schedule a long delay just in case. 2399 */ 2400 schedule_delayed_work(&ctx->tx_work.work, msecs_to_jiffies(10)); 2401 } 2402 } 2403 2404 static bool tls_is_tx_ready(struct tls_sw_context_tx *ctx) 2405 { 2406 struct tls_rec *rec; 2407 2408 rec = list_first_entry_or_null(&ctx->tx_list, struct tls_rec, list); 2409 if (!rec) 2410 return false; 2411 2412 return READ_ONCE(rec->tx_ready); 2413 } 2414 2415 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx) 2416 { 2417 struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx); 2418 2419 /* Schedule the transmission if tx list is ready */ 2420 if (tls_is_tx_ready(tx_ctx) && 2421 !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask)) 2422 schedule_delayed_work(&tx_ctx->tx_work.work, 0); 2423 } 2424 2425 void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx) 2426 { 2427 struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx); 2428 2429 write_lock_bh(&sk->sk_callback_lock); 2430 rx_ctx->saved_data_ready = sk->sk_data_ready; 2431 sk->sk_data_ready = tls_data_ready; 2432 write_unlock_bh(&sk->sk_callback_lock); 2433 } 2434 2435 void tls_update_rx_zc_capable(struct tls_context *tls_ctx) 2436 { 2437 struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx); 2438 2439 rx_ctx->zc_capable = tls_ctx->rx_no_pad || 2440 tls_ctx->prot_info.version != TLS_1_3_VERSION; 2441 } 2442 2443 static struct tls_sw_context_tx *init_ctx_tx(struct tls_context *ctx, struct sock *sk) 2444 { 2445 struct tls_sw_context_tx *sw_ctx_tx; 2446 2447 if (!ctx->priv_ctx_tx) { 2448 sw_ctx_tx = kzalloc_obj(*sw_ctx_tx); 2449 if (!sw_ctx_tx) 2450 return NULL; 2451 } else { 2452 sw_ctx_tx = ctx->priv_ctx_tx; 2453 } 2454 2455 crypto_init_wait(&sw_ctx_tx->async_wait); 2456 atomic_set(&sw_ctx_tx->encrypt_pending, 1); 2457 INIT_LIST_HEAD(&sw_ctx_tx->tx_list); 2458 INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler); 2459 sw_ctx_tx->tx_work.sk = sk; 2460 2461 return sw_ctx_tx; 2462 } 2463 2464 static struct tls_sw_context_rx *init_ctx_rx(struct tls_context *ctx) 2465 { 2466 struct tls_sw_context_rx *sw_ctx_rx; 2467 2468 if (!ctx->priv_ctx_rx) { 2469 sw_ctx_rx = kzalloc_obj(*sw_ctx_rx); 2470 if (!sw_ctx_rx) 2471 return NULL; 2472 } else { 2473 sw_ctx_rx = ctx->priv_ctx_rx; 2474 } 2475 2476 crypto_init_wait(&sw_ctx_rx->async_wait); 2477 atomic_set(&sw_ctx_rx->decrypt_pending, 1); 2478 init_waitqueue_head(&sw_ctx_rx->wq); 2479 skb_queue_head_init(&sw_ctx_rx->rx_list); 2480 skb_queue_head_init(&sw_ctx_rx->async_hold); 2481 2482 return sw_ctx_rx; 2483 } 2484 2485 int init_prot_info(struct tls_prot_info *prot, 2486 const struct tls_crypto_info *crypto_info, 2487 const struct tls_cipher_desc *cipher_desc) 2488 { 2489 u16 nonce_size = cipher_desc->nonce; 2490 2491 if (crypto_info->version == TLS_1_3_VERSION) { 2492 nonce_size = 0; 2493 prot->aad_size = TLS_HEADER_SIZE; 2494 prot->tail_size = 1; 2495 } else { 2496 prot->aad_size = TLS_AAD_SPACE_SIZE; 2497 prot->tail_size = 0; 2498 } 2499 2500 /* Sanity-check the sizes for stack allocations. */ 2501 if (nonce_size > TLS_MAX_IV_SIZE || prot->aad_size > TLS_MAX_AAD_SIZE) 2502 return -EINVAL; 2503 2504 prot->version = crypto_info->version; 2505 prot->cipher_type = crypto_info->cipher_type; 2506 prot->prepend_size = TLS_HEADER_SIZE + nonce_size; 2507 prot->tag_size = cipher_desc->tag; 2508 prot->overhead_size = prot->prepend_size + prot->tag_size + prot->tail_size; 2509 prot->iv_size = cipher_desc->iv; 2510 prot->salt_size = cipher_desc->salt; 2511 prot->rec_seq_size = cipher_desc->rec_seq; 2512 2513 return 0; 2514 } 2515 2516 static void tls_finish_key_update(struct sock *sk, struct tls_context *tls_ctx) 2517 { 2518 struct tls_sw_context_rx *ctx = tls_ctx->priv_ctx_rx; 2519 2520 WRITE_ONCE(ctx->key_update_pending, false); 2521 /* wake-up pre-existing poll() */ 2522 ctx->saved_data_ready(sk); 2523 } 2524 2525 int tls_set_sw_offload(struct sock *sk, int tx, 2526 struct tls_crypto_info *new_crypto_info) 2527 { 2528 struct tls_crypto_info *crypto_info, *src_crypto_info; 2529 struct tls_sw_context_tx *sw_ctx_tx = NULL; 2530 struct tls_sw_context_rx *sw_ctx_rx = NULL; 2531 const struct tls_cipher_desc *cipher_desc; 2532 char *iv, *rec_seq, *key, *salt; 2533 struct cipher_context *cctx; 2534 struct tls_prot_info *prot; 2535 struct crypto_aead **aead; 2536 struct tls_context *ctx; 2537 struct crypto_tfm *tfm; 2538 int rc = 0; 2539 2540 ctx = tls_get_ctx(sk); 2541 prot = &ctx->prot_info; 2542 2543 /* new_crypto_info != NULL means rekey */ 2544 if (!new_crypto_info) { 2545 if (tx) { 2546 ctx->priv_ctx_tx = init_ctx_tx(ctx, sk); 2547 if (!ctx->priv_ctx_tx) 2548 return -ENOMEM; 2549 } else { 2550 ctx->priv_ctx_rx = init_ctx_rx(ctx); 2551 if (!ctx->priv_ctx_rx) 2552 return -ENOMEM; 2553 } 2554 } 2555 2556 if (tx) { 2557 sw_ctx_tx = ctx->priv_ctx_tx; 2558 crypto_info = &ctx->crypto_send.info; 2559 cctx = &ctx->tx; 2560 aead = &sw_ctx_tx->aead_send; 2561 } else { 2562 sw_ctx_rx = ctx->priv_ctx_rx; 2563 crypto_info = &ctx->crypto_recv.info; 2564 cctx = &ctx->rx; 2565 aead = &sw_ctx_rx->aead_recv; 2566 } 2567 2568 src_crypto_info = new_crypto_info ?: crypto_info; 2569 2570 cipher_desc = get_cipher_desc(src_crypto_info->cipher_type); 2571 if (!cipher_desc) { 2572 rc = -EINVAL; 2573 goto free_priv; 2574 } 2575 2576 rc = init_prot_info(prot, src_crypto_info, cipher_desc); 2577 if (rc) 2578 goto free_priv; 2579 2580 iv = crypto_info_iv(src_crypto_info, cipher_desc); 2581 key = crypto_info_key(src_crypto_info, cipher_desc); 2582 salt = crypto_info_salt(src_crypto_info, cipher_desc); 2583 rec_seq = crypto_info_rec_seq(src_crypto_info, cipher_desc); 2584 2585 if (!*aead) { 2586 *aead = crypto_alloc_aead(cipher_desc->cipher_name, 0, 0); 2587 if (IS_ERR(*aead)) { 2588 rc = PTR_ERR(*aead); 2589 *aead = NULL; 2590 goto free_priv; 2591 } 2592 } 2593 2594 ctx->push_pending_record = tls_sw_push_pending_record; 2595 2596 /* setkey is the last operation that could fail during a 2597 * rekey. if it succeeds, we can start modifying the 2598 * context. 2599 */ 2600 rc = crypto_aead_setkey(*aead, key, cipher_desc->key); 2601 if (rc) { 2602 if (new_crypto_info) 2603 goto out; 2604 else 2605 goto free_aead; 2606 } 2607 2608 if (!new_crypto_info) { 2609 rc = crypto_aead_setauthsize(*aead, prot->tag_size); 2610 if (rc) 2611 goto free_aead; 2612 } 2613 2614 if (!tx && !new_crypto_info) { 2615 tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv); 2616 2617 tls_update_rx_zc_capable(ctx); 2618 sw_ctx_rx->async_capable = 2619 src_crypto_info->version != TLS_1_3_VERSION && 2620 !!(tfm->__crt_alg->cra_flags & CRYPTO_ALG_ASYNC); 2621 2622 rc = tls_strp_init(&sw_ctx_rx->strp, sk); 2623 if (rc) 2624 goto free_aead; 2625 } 2626 2627 memcpy(cctx->iv, salt, cipher_desc->salt); 2628 memcpy(cctx->iv + cipher_desc->salt, iv, cipher_desc->iv); 2629 memcpy(cctx->rec_seq, rec_seq, cipher_desc->rec_seq); 2630 2631 if (new_crypto_info) { 2632 unsafe_memcpy(crypto_info, new_crypto_info, 2633 cipher_desc->crypto_info, 2634 /* size was checked in do_tls_setsockopt_conf */); 2635 memzero_explicit(new_crypto_info, cipher_desc->crypto_info); 2636 if (!tx) 2637 tls_finish_key_update(sk, ctx); 2638 } 2639 2640 goto out; 2641 2642 free_aead: 2643 crypto_free_aead(*aead); 2644 *aead = NULL; 2645 free_priv: 2646 if (!new_crypto_info) { 2647 if (tx) { 2648 kfree(ctx->priv_ctx_tx); 2649 ctx->priv_ctx_tx = NULL; 2650 } else { 2651 kfree(ctx->priv_ctx_rx); 2652 ctx->priv_ctx_rx = NULL; 2653 } 2654 } 2655 out: 2656 return rc; 2657 } 2658