1 /* Copyright (c) 2018, Mellanox Technologies All rights reserved. 2 * 3 * This software is available to you under a choice of one of two 4 * licenses. You may choose to be licensed under the terms of the GNU 5 * General Public License (GPL) Version 2, available from the file 6 * COPYING in the main directory of this source tree, or the 7 * OpenIB.org BSD license below: 8 * 9 * Redistribution and use in source and binary forms, with or 10 * without modification, are permitted provided that the following 11 * conditions are met: 12 * 13 * - Redistributions of source code must retain the above 14 * copyright notice, this list of conditions and the following 15 * disclaimer. 16 * 17 * - Redistributions in binary form must reproduce the above 18 * copyright notice, this list of conditions and the following 19 * disclaimer in the documentation and/or other materials 20 * provided with the distribution. 21 * 22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 23 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 25 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 26 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 27 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 28 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 29 * SOFTWARE. 30 */ 31 32 #include <crypto/aead.h> 33 #include <linux/highmem.h> 34 #include <linux/module.h> 35 #include <linux/netdevice.h> 36 #include <net/dst.h> 37 #include <net/inet_connection_sock.h> 38 #include <net/tcp.h> 39 #include <net/tls.h> 40 41 #include "tls.h" 42 #include "trace.h" 43 44 /* device_offload_lock is used to synchronize tls_dev_add 45 * against NETDEV_DOWN notifications. 46 */ 47 static DECLARE_RWSEM(device_offload_lock); 48 49 static struct workqueue_struct *destruct_wq __read_mostly; 50 51 static LIST_HEAD(tls_device_list); 52 static LIST_HEAD(tls_device_down_list); 53 static DEFINE_SPINLOCK(tls_device_lock); 54 55 static void tls_device_free_ctx(struct tls_context *ctx) 56 { 57 if (ctx->tx_conf == TLS_HW) { 58 kfree(tls_offload_ctx_tx(ctx)); 59 kfree(ctx->tx.rec_seq); 60 kfree(ctx->tx.iv); 61 } 62 63 if (ctx->rx_conf == TLS_HW) 64 kfree(tls_offload_ctx_rx(ctx)); 65 66 tls_ctx_free(NULL, ctx); 67 } 68 69 static void tls_device_tx_del_task(struct work_struct *work) 70 { 71 struct tls_offload_context_tx *offload_ctx = 72 container_of(work, struct tls_offload_context_tx, destruct_work); 73 struct tls_context *ctx = offload_ctx->ctx; 74 struct net_device *netdev; 75 76 /* Safe, because this is the destroy flow, refcount is 0, so 77 * tls_device_down can't store this field in parallel. 78 */ 79 netdev = rcu_dereference_protected(ctx->netdev, 80 !refcount_read(&ctx->refcount)); 81 82 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, TLS_OFFLOAD_CTX_DIR_TX); 83 dev_put(netdev); 84 ctx->netdev = NULL; 85 tls_device_free_ctx(ctx); 86 } 87 88 static void tls_device_queue_ctx_destruction(struct tls_context *ctx) 89 { 90 struct net_device *netdev; 91 unsigned long flags; 92 bool async_cleanup; 93 94 spin_lock_irqsave(&tls_device_lock, flags); 95 if (unlikely(!refcount_dec_and_test(&ctx->refcount))) { 96 spin_unlock_irqrestore(&tls_device_lock, flags); 97 return; 98 } 99 100 list_del(&ctx->list); /* Remove from tls_device_list / tls_device_down_list */ 101 102 /* Safe, because this is the destroy flow, refcount is 0, so 103 * tls_device_down can't store this field in parallel. 104 */ 105 netdev = rcu_dereference_protected(ctx->netdev, 106 !refcount_read(&ctx->refcount)); 107 108 async_cleanup = netdev && ctx->tx_conf == TLS_HW; 109 if (async_cleanup) { 110 struct tls_offload_context_tx *offload_ctx = tls_offload_ctx_tx(ctx); 111 112 /* queue_work inside the spinlock 113 * to make sure tls_device_down waits for that work. 114 */ 115 queue_work(destruct_wq, &offload_ctx->destruct_work); 116 } 117 spin_unlock_irqrestore(&tls_device_lock, flags); 118 119 if (!async_cleanup) 120 tls_device_free_ctx(ctx); 121 } 122 123 /* We assume that the socket is already connected */ 124 static struct net_device *get_netdev_for_sock(struct sock *sk) 125 { 126 struct dst_entry *dst = sk_dst_get(sk); 127 struct net_device *netdev = NULL; 128 129 if (likely(dst)) { 130 netdev = netdev_sk_get_lowest_dev(dst->dev, sk); 131 dev_hold(netdev); 132 } 133 134 dst_release(dst); 135 136 return netdev; 137 } 138 139 static void destroy_record(struct tls_record_info *record) 140 { 141 int i; 142 143 for (i = 0; i < record->num_frags; i++) 144 __skb_frag_unref(&record->frags[i], false); 145 kfree(record); 146 } 147 148 static void delete_all_records(struct tls_offload_context_tx *offload_ctx) 149 { 150 struct tls_record_info *info, *temp; 151 152 list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) { 153 list_del(&info->list); 154 destroy_record(info); 155 } 156 157 offload_ctx->retransmit_hint = NULL; 158 } 159 160 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq) 161 { 162 struct tls_context *tls_ctx = tls_get_ctx(sk); 163 struct tls_record_info *info, *temp; 164 struct tls_offload_context_tx *ctx; 165 u64 deleted_records = 0; 166 unsigned long flags; 167 168 if (!tls_ctx) 169 return; 170 171 ctx = tls_offload_ctx_tx(tls_ctx); 172 173 spin_lock_irqsave(&ctx->lock, flags); 174 info = ctx->retransmit_hint; 175 if (info && !before(acked_seq, info->end_seq)) 176 ctx->retransmit_hint = NULL; 177 178 list_for_each_entry_safe(info, temp, &ctx->records_list, list) { 179 if (before(acked_seq, info->end_seq)) 180 break; 181 list_del(&info->list); 182 183 destroy_record(info); 184 deleted_records++; 185 } 186 187 ctx->unacked_record_sn += deleted_records; 188 spin_unlock_irqrestore(&ctx->lock, flags); 189 } 190 191 /* At this point, there should be no references on this 192 * socket and no in-flight SKBs associated with this 193 * socket, so it is safe to free all the resources. 194 */ 195 void tls_device_sk_destruct(struct sock *sk) 196 { 197 struct tls_context *tls_ctx = tls_get_ctx(sk); 198 struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx); 199 200 tls_ctx->sk_destruct(sk); 201 202 if (tls_ctx->tx_conf == TLS_HW) { 203 if (ctx->open_record) 204 destroy_record(ctx->open_record); 205 delete_all_records(ctx); 206 crypto_free_aead(ctx->aead_send); 207 clean_acked_data_disable(inet_csk(sk)); 208 } 209 210 tls_device_queue_ctx_destruction(tls_ctx); 211 } 212 EXPORT_SYMBOL_GPL(tls_device_sk_destruct); 213 214 void tls_device_free_resources_tx(struct sock *sk) 215 { 216 struct tls_context *tls_ctx = tls_get_ctx(sk); 217 218 tls_free_partial_record(sk, tls_ctx); 219 } 220 221 void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq) 222 { 223 struct tls_context *tls_ctx = tls_get_ctx(sk); 224 225 trace_tls_device_tx_resync_req(sk, got_seq, exp_seq); 226 WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags)); 227 } 228 EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request); 229 230 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx, 231 u32 seq) 232 { 233 struct net_device *netdev; 234 struct sk_buff *skb; 235 int err = 0; 236 u8 *rcd_sn; 237 238 skb = tcp_write_queue_tail(sk); 239 if (skb) 240 TCP_SKB_CB(skb)->eor = 1; 241 242 rcd_sn = tls_ctx->tx.rec_seq; 243 244 trace_tls_device_tx_resync_send(sk, seq, rcd_sn); 245 down_read(&device_offload_lock); 246 netdev = rcu_dereference_protected(tls_ctx->netdev, 247 lockdep_is_held(&device_offload_lock)); 248 if (netdev) 249 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, 250 rcd_sn, 251 TLS_OFFLOAD_CTX_DIR_TX); 252 up_read(&device_offload_lock); 253 if (err) 254 return; 255 256 clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags); 257 } 258 259 static void tls_append_frag(struct tls_record_info *record, 260 struct page_frag *pfrag, 261 int size) 262 { 263 skb_frag_t *frag; 264 265 frag = &record->frags[record->num_frags - 1]; 266 if (skb_frag_page(frag) == pfrag->page && 267 skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) { 268 skb_frag_size_add(frag, size); 269 } else { 270 ++frag; 271 __skb_frag_set_page(frag, pfrag->page); 272 skb_frag_off_set(frag, pfrag->offset); 273 skb_frag_size_set(frag, size); 274 ++record->num_frags; 275 get_page(pfrag->page); 276 } 277 278 pfrag->offset += size; 279 record->len += size; 280 } 281 282 static int tls_push_record(struct sock *sk, 283 struct tls_context *ctx, 284 struct tls_offload_context_tx *offload_ctx, 285 struct tls_record_info *record, 286 int flags) 287 { 288 struct tls_prot_info *prot = &ctx->prot_info; 289 struct tcp_sock *tp = tcp_sk(sk); 290 skb_frag_t *frag; 291 int i; 292 293 record->end_seq = tp->write_seq + record->len; 294 list_add_tail_rcu(&record->list, &offload_ctx->records_list); 295 offload_ctx->open_record = NULL; 296 297 if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags)) 298 tls_device_resync_tx(sk, ctx, tp->write_seq); 299 300 tls_advance_record_sn(sk, prot, &ctx->tx); 301 302 for (i = 0; i < record->num_frags; i++) { 303 frag = &record->frags[i]; 304 sg_unmark_end(&offload_ctx->sg_tx_data[i]); 305 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag), 306 skb_frag_size(frag), skb_frag_off(frag)); 307 sk_mem_charge(sk, skb_frag_size(frag)); 308 get_page(skb_frag_page(frag)); 309 } 310 sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]); 311 312 /* all ready, send */ 313 return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags); 314 } 315 316 static int tls_device_record_close(struct sock *sk, 317 struct tls_context *ctx, 318 struct tls_record_info *record, 319 struct page_frag *pfrag, 320 unsigned char record_type) 321 { 322 struct tls_prot_info *prot = &ctx->prot_info; 323 int ret; 324 325 /* append tag 326 * device will fill in the tag, we just need to append a placeholder 327 * use socket memory to improve coalescing (re-using a single buffer 328 * increases frag count) 329 * if we can't allocate memory now, steal some back from data 330 */ 331 if (likely(skb_page_frag_refill(prot->tag_size, pfrag, 332 sk->sk_allocation))) { 333 ret = 0; 334 tls_append_frag(record, pfrag, prot->tag_size); 335 } else { 336 ret = prot->tag_size; 337 if (record->len <= prot->overhead_size) 338 return -ENOMEM; 339 } 340 341 /* fill prepend */ 342 tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]), 343 record->len - prot->overhead_size, 344 record_type); 345 return ret; 346 } 347 348 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx, 349 struct page_frag *pfrag, 350 size_t prepend_size) 351 { 352 struct tls_record_info *record; 353 skb_frag_t *frag; 354 355 record = kmalloc(sizeof(*record), GFP_KERNEL); 356 if (!record) 357 return -ENOMEM; 358 359 frag = &record->frags[0]; 360 __skb_frag_set_page(frag, pfrag->page); 361 skb_frag_off_set(frag, pfrag->offset); 362 skb_frag_size_set(frag, prepend_size); 363 364 get_page(pfrag->page); 365 pfrag->offset += prepend_size; 366 367 record->num_frags = 1; 368 record->len = prepend_size; 369 offload_ctx->open_record = record; 370 return 0; 371 } 372 373 static int tls_do_allocation(struct sock *sk, 374 struct tls_offload_context_tx *offload_ctx, 375 struct page_frag *pfrag, 376 size_t prepend_size) 377 { 378 int ret; 379 380 if (!offload_ctx->open_record) { 381 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag, 382 sk->sk_allocation))) { 383 READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk); 384 sk_stream_moderate_sndbuf(sk); 385 return -ENOMEM; 386 } 387 388 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size); 389 if (ret) 390 return ret; 391 392 if (pfrag->size > pfrag->offset) 393 return 0; 394 } 395 396 if (!sk_page_frag_refill(sk, pfrag)) 397 return -ENOMEM; 398 399 return 0; 400 } 401 402 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i) 403 { 404 size_t pre_copy, nocache; 405 406 pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1); 407 if (pre_copy) { 408 pre_copy = min(pre_copy, bytes); 409 if (copy_from_iter(addr, pre_copy, i) != pre_copy) 410 return -EFAULT; 411 bytes -= pre_copy; 412 addr += pre_copy; 413 } 414 415 nocache = round_down(bytes, SMP_CACHE_BYTES); 416 if (copy_from_iter_nocache(addr, nocache, i) != nocache) 417 return -EFAULT; 418 bytes -= nocache; 419 addr += nocache; 420 421 if (bytes && copy_from_iter(addr, bytes, i) != bytes) 422 return -EFAULT; 423 424 return 0; 425 } 426 427 union tls_iter_offset { 428 struct iov_iter *msg_iter; 429 int offset; 430 }; 431 432 static int tls_push_data(struct sock *sk, 433 union tls_iter_offset iter_offset, 434 size_t size, int flags, 435 unsigned char record_type, 436 struct page *zc_page) 437 { 438 struct tls_context *tls_ctx = tls_get_ctx(sk); 439 struct tls_prot_info *prot = &tls_ctx->prot_info; 440 struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx); 441 struct tls_record_info *record; 442 int tls_push_record_flags; 443 struct page_frag *pfrag; 444 size_t orig_size = size; 445 u32 max_open_record_len; 446 bool more = false; 447 bool done = false; 448 int copy, rc = 0; 449 long timeo; 450 451 if (flags & 452 ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST)) 453 return -EOPNOTSUPP; 454 455 if (unlikely(sk->sk_err)) 456 return -sk->sk_err; 457 458 flags |= MSG_SENDPAGE_DECRYPTED; 459 tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST; 460 461 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); 462 if (tls_is_partially_sent_record(tls_ctx)) { 463 rc = tls_push_partial_record(sk, tls_ctx, flags); 464 if (rc < 0) 465 return rc; 466 } 467 468 pfrag = sk_page_frag(sk); 469 470 /* TLS_HEADER_SIZE is not counted as part of the TLS record, and 471 * we need to leave room for an authentication tag. 472 */ 473 max_open_record_len = TLS_MAX_PAYLOAD_SIZE + 474 prot->prepend_size; 475 do { 476 rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size); 477 if (unlikely(rc)) { 478 rc = sk_stream_wait_memory(sk, &timeo); 479 if (!rc) 480 continue; 481 482 record = ctx->open_record; 483 if (!record) 484 break; 485 handle_error: 486 if (record_type != TLS_RECORD_TYPE_DATA) { 487 /* avoid sending partial 488 * record with type != 489 * application_data 490 */ 491 size = orig_size; 492 destroy_record(record); 493 ctx->open_record = NULL; 494 } else if (record->len > prot->prepend_size) { 495 goto last_record; 496 } 497 498 break; 499 } 500 501 record = ctx->open_record; 502 503 copy = min_t(size_t, size, max_open_record_len - record->len); 504 if (copy && zc_page) { 505 struct page_frag zc_pfrag; 506 507 zc_pfrag.page = zc_page; 508 zc_pfrag.offset = iter_offset.offset; 509 zc_pfrag.size = copy; 510 tls_append_frag(record, &zc_pfrag, copy); 511 } else if (copy) { 512 copy = min_t(size_t, copy, pfrag->size - pfrag->offset); 513 514 rc = tls_device_copy_data(page_address(pfrag->page) + 515 pfrag->offset, copy, 516 iter_offset.msg_iter); 517 if (rc) 518 goto handle_error; 519 tls_append_frag(record, pfrag, copy); 520 } 521 522 size -= copy; 523 if (!size) { 524 last_record: 525 tls_push_record_flags = flags; 526 if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) { 527 more = true; 528 break; 529 } 530 531 done = true; 532 } 533 534 if (done || record->len >= max_open_record_len || 535 (record->num_frags >= MAX_SKB_FRAGS - 1)) { 536 rc = tls_device_record_close(sk, tls_ctx, record, 537 pfrag, record_type); 538 if (rc) { 539 if (rc > 0) { 540 size += rc; 541 } else { 542 size = orig_size; 543 destroy_record(record); 544 ctx->open_record = NULL; 545 break; 546 } 547 } 548 549 rc = tls_push_record(sk, 550 tls_ctx, 551 ctx, 552 record, 553 tls_push_record_flags); 554 if (rc < 0) 555 break; 556 } 557 } while (!done); 558 559 tls_ctx->pending_open_record_frags = more; 560 561 if (orig_size - size > 0) 562 rc = orig_size - size; 563 564 return rc; 565 } 566 567 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) 568 { 569 unsigned char record_type = TLS_RECORD_TYPE_DATA; 570 struct tls_context *tls_ctx = tls_get_ctx(sk); 571 union tls_iter_offset iter; 572 int rc; 573 574 mutex_lock(&tls_ctx->tx_lock); 575 lock_sock(sk); 576 577 if (unlikely(msg->msg_controllen)) { 578 rc = tls_process_cmsg(sk, msg, &record_type); 579 if (rc) 580 goto out; 581 } 582 583 iter.msg_iter = &msg->msg_iter; 584 rc = tls_push_data(sk, iter, size, msg->msg_flags, record_type, NULL); 585 586 out: 587 release_sock(sk); 588 mutex_unlock(&tls_ctx->tx_lock); 589 return rc; 590 } 591 592 int tls_device_sendpage(struct sock *sk, struct page *page, 593 int offset, size_t size, int flags) 594 { 595 struct tls_context *tls_ctx = tls_get_ctx(sk); 596 union tls_iter_offset iter_offset; 597 struct iov_iter msg_iter; 598 char *kaddr; 599 struct kvec iov; 600 int rc; 601 602 if (flags & MSG_SENDPAGE_NOTLAST) 603 flags |= MSG_MORE; 604 605 mutex_lock(&tls_ctx->tx_lock); 606 lock_sock(sk); 607 608 if (flags & MSG_OOB) { 609 rc = -EOPNOTSUPP; 610 goto out; 611 } 612 613 if (tls_ctx->zerocopy_sendfile) { 614 iter_offset.offset = offset; 615 rc = tls_push_data(sk, iter_offset, size, 616 flags, TLS_RECORD_TYPE_DATA, page); 617 goto out; 618 } 619 620 kaddr = kmap(page); 621 iov.iov_base = kaddr + offset; 622 iov.iov_len = size; 623 iov_iter_kvec(&msg_iter, ITER_SOURCE, &iov, 1, size); 624 iter_offset.msg_iter = &msg_iter; 625 rc = tls_push_data(sk, iter_offset, size, flags, TLS_RECORD_TYPE_DATA, 626 NULL); 627 kunmap(page); 628 629 out: 630 release_sock(sk); 631 mutex_unlock(&tls_ctx->tx_lock); 632 return rc; 633 } 634 635 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 636 u32 seq, u64 *p_record_sn) 637 { 638 u64 record_sn = context->hint_record_sn; 639 struct tls_record_info *info, *last; 640 641 info = context->retransmit_hint; 642 if (!info || 643 before(seq, info->end_seq - info->len)) { 644 /* if retransmit_hint is irrelevant start 645 * from the beginning of the list 646 */ 647 info = list_first_entry_or_null(&context->records_list, 648 struct tls_record_info, list); 649 if (!info) 650 return NULL; 651 /* send the start_marker record if seq number is before the 652 * tls offload start marker sequence number. This record is 653 * required to handle TCP packets which are before TLS offload 654 * started. 655 * And if it's not start marker, look if this seq number 656 * belongs to the list. 657 */ 658 if (likely(!tls_record_is_start_marker(info))) { 659 /* we have the first record, get the last record to see 660 * if this seq number belongs to the list. 661 */ 662 last = list_last_entry(&context->records_list, 663 struct tls_record_info, list); 664 665 if (!between(seq, tls_record_start_seq(info), 666 last->end_seq)) 667 return NULL; 668 } 669 record_sn = context->unacked_record_sn; 670 } 671 672 /* We just need the _rcu for the READ_ONCE() */ 673 rcu_read_lock(); 674 list_for_each_entry_from_rcu(info, &context->records_list, list) { 675 if (before(seq, info->end_seq)) { 676 if (!context->retransmit_hint || 677 after(info->end_seq, 678 context->retransmit_hint->end_seq)) { 679 context->hint_record_sn = record_sn; 680 context->retransmit_hint = info; 681 } 682 *p_record_sn = record_sn; 683 goto exit_rcu_unlock; 684 } 685 record_sn++; 686 } 687 info = NULL; 688 689 exit_rcu_unlock: 690 rcu_read_unlock(); 691 return info; 692 } 693 EXPORT_SYMBOL(tls_get_record); 694 695 static int tls_device_push_pending_record(struct sock *sk, int flags) 696 { 697 union tls_iter_offset iter; 698 struct iov_iter msg_iter; 699 700 iov_iter_kvec(&msg_iter, ITER_SOURCE, NULL, 0, 0); 701 iter.msg_iter = &msg_iter; 702 return tls_push_data(sk, iter, 0, flags, TLS_RECORD_TYPE_DATA, NULL); 703 } 704 705 void tls_device_write_space(struct sock *sk, struct tls_context *ctx) 706 { 707 if (tls_is_partially_sent_record(ctx)) { 708 gfp_t sk_allocation = sk->sk_allocation; 709 710 WARN_ON_ONCE(sk->sk_write_pending); 711 712 sk->sk_allocation = GFP_ATOMIC; 713 tls_push_partial_record(sk, ctx, 714 MSG_DONTWAIT | MSG_NOSIGNAL | 715 MSG_SENDPAGE_DECRYPTED); 716 sk->sk_allocation = sk_allocation; 717 } 718 } 719 720 static void tls_device_resync_rx(struct tls_context *tls_ctx, 721 struct sock *sk, u32 seq, u8 *rcd_sn) 722 { 723 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 724 struct net_device *netdev; 725 726 trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type); 727 rcu_read_lock(); 728 netdev = rcu_dereference(tls_ctx->netdev); 729 if (netdev) 730 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn, 731 TLS_OFFLOAD_CTX_DIR_RX); 732 rcu_read_unlock(); 733 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC); 734 } 735 736 static bool 737 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async, 738 s64 resync_req, u32 *seq, u16 *rcd_delta) 739 { 740 u32 is_async = resync_req & RESYNC_REQ_ASYNC; 741 u32 req_seq = resync_req >> 32; 742 u32 req_end = req_seq + ((resync_req >> 16) & 0xffff); 743 u16 i; 744 745 *rcd_delta = 0; 746 747 if (is_async) { 748 /* shouldn't get to wraparound: 749 * too long in async stage, something bad happened 750 */ 751 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX)) 752 return false; 753 754 /* asynchronous stage: log all headers seq such that 755 * req_seq <= seq <= end_seq, and wait for real resync request 756 */ 757 if (before(*seq, req_seq)) 758 return false; 759 if (!after(*seq, req_end) && 760 resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX) 761 resync_async->log[resync_async->loglen++] = *seq; 762 763 resync_async->rcd_delta++; 764 765 return false; 766 } 767 768 /* synchronous stage: check against the logged entries and 769 * proceed to check the next entries if no match was found 770 */ 771 for (i = 0; i < resync_async->loglen; i++) 772 if (req_seq == resync_async->log[i] && 773 atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) { 774 *rcd_delta = resync_async->rcd_delta - i; 775 *seq = req_seq; 776 resync_async->loglen = 0; 777 resync_async->rcd_delta = 0; 778 return true; 779 } 780 781 resync_async->loglen = 0; 782 resync_async->rcd_delta = 0; 783 784 if (req_seq == *seq && 785 atomic64_try_cmpxchg(&resync_async->req, 786 &resync_req, 0)) 787 return true; 788 789 return false; 790 } 791 792 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq) 793 { 794 struct tls_context *tls_ctx = tls_get_ctx(sk); 795 struct tls_offload_context_rx *rx_ctx; 796 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; 797 u32 sock_data, is_req_pending; 798 struct tls_prot_info *prot; 799 s64 resync_req; 800 u16 rcd_delta; 801 u32 req_seq; 802 803 if (tls_ctx->rx_conf != TLS_HW) 804 return; 805 if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) 806 return; 807 808 prot = &tls_ctx->prot_info; 809 rx_ctx = tls_offload_ctx_rx(tls_ctx); 810 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); 811 812 switch (rx_ctx->resync_type) { 813 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ: 814 resync_req = atomic64_read(&rx_ctx->resync_req); 815 req_seq = resync_req >> 32; 816 seq += TLS_HEADER_SIZE - 1; 817 is_req_pending = resync_req; 818 819 if (likely(!is_req_pending) || req_seq != seq || 820 !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0)) 821 return; 822 break; 823 case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT: 824 if (likely(!rx_ctx->resync_nh_do_now)) 825 return; 826 827 /* head of next rec is already in, note that the sock_inq will 828 * include the currently parsed message when called from parser 829 */ 830 sock_data = tcp_inq(sk); 831 if (sock_data > rcd_len) { 832 trace_tls_device_rx_resync_nh_delay(sk, sock_data, 833 rcd_len); 834 return; 835 } 836 837 rx_ctx->resync_nh_do_now = 0; 838 seq += rcd_len; 839 tls_bigint_increment(rcd_sn, prot->rec_seq_size); 840 break; 841 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC: 842 resync_req = atomic64_read(&rx_ctx->resync_async->req); 843 is_req_pending = resync_req; 844 if (likely(!is_req_pending)) 845 return; 846 847 if (!tls_device_rx_resync_async(rx_ctx->resync_async, 848 resync_req, &seq, &rcd_delta)) 849 return; 850 tls_bigint_subtract(rcd_sn, rcd_delta); 851 break; 852 } 853 854 tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn); 855 } 856 857 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx, 858 struct tls_offload_context_rx *ctx, 859 struct sock *sk, struct sk_buff *skb) 860 { 861 struct strp_msg *rxm; 862 863 /* device will request resyncs by itself based on stream scan */ 864 if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT) 865 return; 866 /* already scheduled */ 867 if (ctx->resync_nh_do_now) 868 return; 869 /* seen decrypted fragments since last fully-failed record */ 870 if (ctx->resync_nh_reset) { 871 ctx->resync_nh_reset = 0; 872 ctx->resync_nh.decrypted_failed = 1; 873 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL; 874 return; 875 } 876 877 if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt) 878 return; 879 880 /* doing resync, bump the next target in case it fails */ 881 if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL) 882 ctx->resync_nh.decrypted_tgt *= 2; 883 else 884 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL; 885 886 rxm = strp_msg(skb); 887 888 /* head of next rec is already in, parser will sync for us */ 889 if (tcp_inq(sk) > rxm->full_len) { 890 trace_tls_device_rx_resync_nh_schedule(sk); 891 ctx->resync_nh_do_now = 1; 892 } else { 893 struct tls_prot_info *prot = &tls_ctx->prot_info; 894 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; 895 896 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); 897 tls_bigint_increment(rcd_sn, prot->rec_seq_size); 898 899 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq, 900 rcd_sn); 901 } 902 } 903 904 static int 905 tls_device_reencrypt(struct sock *sk, struct tls_context *tls_ctx) 906 { 907 struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx); 908 const struct tls_cipher_size_desc *cipher_sz; 909 int err, offset, copy, data_len, pos; 910 struct sk_buff *skb, *skb_iter; 911 struct scatterlist sg[1]; 912 struct strp_msg *rxm; 913 char *orig_buf, *buf; 914 915 switch (tls_ctx->crypto_recv.info.cipher_type) { 916 case TLS_CIPHER_AES_GCM_128: 917 case TLS_CIPHER_AES_GCM_256: 918 break; 919 default: 920 return -EINVAL; 921 } 922 cipher_sz = &tls_cipher_size_desc[tls_ctx->crypto_recv.info.cipher_type]; 923 924 rxm = strp_msg(tls_strp_msg(sw_ctx)); 925 orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv, 926 sk->sk_allocation); 927 if (!orig_buf) 928 return -ENOMEM; 929 buf = orig_buf; 930 931 err = tls_strp_msg_cow(sw_ctx); 932 if (unlikely(err)) 933 goto free_buf; 934 935 skb = tls_strp_msg(sw_ctx); 936 rxm = strp_msg(skb); 937 offset = rxm->offset; 938 939 sg_init_table(sg, 1); 940 sg_set_buf(&sg[0], buf, 941 rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv); 942 err = skb_copy_bits(skb, offset, buf, TLS_HEADER_SIZE + cipher_sz->iv); 943 if (err) 944 goto free_buf; 945 946 /* We are interested only in the decrypted data not the auth */ 947 err = decrypt_skb(sk, sg); 948 if (err != -EBADMSG) 949 goto free_buf; 950 else 951 err = 0; 952 953 data_len = rxm->full_len - cipher_sz->tag; 954 955 if (skb_pagelen(skb) > offset) { 956 copy = min_t(int, skb_pagelen(skb) - offset, data_len); 957 958 if (skb->decrypted) { 959 err = skb_store_bits(skb, offset, buf, copy); 960 if (err) 961 goto free_buf; 962 } 963 964 offset += copy; 965 buf += copy; 966 } 967 968 pos = skb_pagelen(skb); 969 skb_walk_frags(skb, skb_iter) { 970 int frag_pos; 971 972 /* Practically all frags must belong to msg if reencrypt 973 * is needed with current strparser and coalescing logic, 974 * but strparser may "get optimized", so let's be safe. 975 */ 976 if (pos + skb_iter->len <= offset) 977 goto done_with_frag; 978 if (pos >= data_len + rxm->offset) 979 break; 980 981 frag_pos = offset - pos; 982 copy = min_t(int, skb_iter->len - frag_pos, 983 data_len + rxm->offset - offset); 984 985 if (skb_iter->decrypted) { 986 err = skb_store_bits(skb_iter, frag_pos, buf, copy); 987 if (err) 988 goto free_buf; 989 } 990 991 offset += copy; 992 buf += copy; 993 done_with_frag: 994 pos += skb_iter->len; 995 } 996 997 free_buf: 998 kfree(orig_buf); 999 return err; 1000 } 1001 1002 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx) 1003 { 1004 struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx); 1005 struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx); 1006 struct sk_buff *skb = tls_strp_msg(sw_ctx); 1007 struct strp_msg *rxm = strp_msg(skb); 1008 int is_decrypted = skb->decrypted; 1009 int is_encrypted = !is_decrypted; 1010 struct sk_buff *skb_iter; 1011 int left; 1012 1013 left = rxm->full_len - skb->len; 1014 /* Check if all the data is decrypted already */ 1015 skb_iter = skb_shinfo(skb)->frag_list; 1016 while (skb_iter && left > 0) { 1017 is_decrypted &= skb_iter->decrypted; 1018 is_encrypted &= !skb_iter->decrypted; 1019 1020 left -= skb_iter->len; 1021 skb_iter = skb_iter->next; 1022 } 1023 1024 trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len, 1025 tls_ctx->rx.rec_seq, rxm->full_len, 1026 is_encrypted, is_decrypted); 1027 1028 if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) { 1029 if (likely(is_encrypted || is_decrypted)) 1030 return is_decrypted; 1031 1032 /* After tls_device_down disables the offload, the next SKB will 1033 * likely have initial fragments decrypted, and final ones not 1034 * decrypted. We need to reencrypt that single SKB. 1035 */ 1036 return tls_device_reencrypt(sk, tls_ctx); 1037 } 1038 1039 /* Return immediately if the record is either entirely plaintext or 1040 * entirely ciphertext. Otherwise handle reencrypt partially decrypted 1041 * record. 1042 */ 1043 if (is_decrypted) { 1044 ctx->resync_nh_reset = 1; 1045 return is_decrypted; 1046 } 1047 if (is_encrypted) { 1048 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb); 1049 return 0; 1050 } 1051 1052 ctx->resync_nh_reset = 1; 1053 return tls_device_reencrypt(sk, tls_ctx); 1054 } 1055 1056 static void tls_device_attach(struct tls_context *ctx, struct sock *sk, 1057 struct net_device *netdev) 1058 { 1059 if (sk->sk_destruct != tls_device_sk_destruct) { 1060 refcount_set(&ctx->refcount, 1); 1061 dev_hold(netdev); 1062 RCU_INIT_POINTER(ctx->netdev, netdev); 1063 spin_lock_irq(&tls_device_lock); 1064 list_add_tail(&ctx->list, &tls_device_list); 1065 spin_unlock_irq(&tls_device_lock); 1066 1067 ctx->sk_destruct = sk->sk_destruct; 1068 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct); 1069 } 1070 } 1071 1072 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx) 1073 { 1074 struct tls_context *tls_ctx = tls_get_ctx(sk); 1075 struct tls_prot_info *prot = &tls_ctx->prot_info; 1076 const struct tls_cipher_size_desc *cipher_sz; 1077 struct tls_record_info *start_marker_record; 1078 struct tls_offload_context_tx *offload_ctx; 1079 struct tls_crypto_info *crypto_info; 1080 struct net_device *netdev; 1081 char *iv, *rec_seq; 1082 struct sk_buff *skb; 1083 __be64 rcd_sn; 1084 int rc; 1085 1086 if (!ctx) 1087 return -EINVAL; 1088 1089 if (ctx->priv_ctx_tx) 1090 return -EEXIST; 1091 1092 netdev = get_netdev_for_sock(sk); 1093 if (!netdev) { 1094 pr_err_ratelimited("%s: netdev not found\n", __func__); 1095 return -EINVAL; 1096 } 1097 1098 if (!(netdev->features & NETIF_F_HW_TLS_TX)) { 1099 rc = -EOPNOTSUPP; 1100 goto release_netdev; 1101 } 1102 1103 crypto_info = &ctx->crypto_send.info; 1104 if (crypto_info->version != TLS_1_2_VERSION) { 1105 rc = -EOPNOTSUPP; 1106 goto release_netdev; 1107 } 1108 1109 switch (crypto_info->cipher_type) { 1110 case TLS_CIPHER_AES_GCM_128: 1111 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv; 1112 rec_seq = 1113 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq; 1114 break; 1115 case TLS_CIPHER_AES_GCM_256: 1116 iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv; 1117 rec_seq = 1118 ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq; 1119 break; 1120 default: 1121 rc = -EINVAL; 1122 goto release_netdev; 1123 } 1124 cipher_sz = &tls_cipher_size_desc[crypto_info->cipher_type]; 1125 1126 /* Sanity-check the rec_seq_size for stack allocations */ 1127 if (cipher_sz->rec_seq > TLS_MAX_REC_SEQ_SIZE) { 1128 rc = -EINVAL; 1129 goto release_netdev; 1130 } 1131 1132 prot->version = crypto_info->version; 1133 prot->cipher_type = crypto_info->cipher_type; 1134 prot->prepend_size = TLS_HEADER_SIZE + cipher_sz->iv; 1135 prot->tag_size = cipher_sz->tag; 1136 prot->overhead_size = prot->prepend_size + prot->tag_size; 1137 prot->iv_size = cipher_sz->iv; 1138 prot->salt_size = cipher_sz->salt; 1139 ctx->tx.iv = kmalloc(cipher_sz->iv + cipher_sz->salt, GFP_KERNEL); 1140 if (!ctx->tx.iv) { 1141 rc = -ENOMEM; 1142 goto release_netdev; 1143 } 1144 1145 memcpy(ctx->tx.iv + cipher_sz->salt, iv, cipher_sz->iv); 1146 1147 prot->rec_seq_size = cipher_sz->rec_seq; 1148 ctx->tx.rec_seq = kmemdup(rec_seq, cipher_sz->rec_seq, GFP_KERNEL); 1149 if (!ctx->tx.rec_seq) { 1150 rc = -ENOMEM; 1151 goto free_iv; 1152 } 1153 1154 start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL); 1155 if (!start_marker_record) { 1156 rc = -ENOMEM; 1157 goto free_rec_seq; 1158 } 1159 1160 offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL); 1161 if (!offload_ctx) { 1162 rc = -ENOMEM; 1163 goto free_marker_record; 1164 } 1165 1166 rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info); 1167 if (rc) 1168 goto free_offload_ctx; 1169 1170 /* start at rec_seq - 1 to account for the start marker record */ 1171 memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn)); 1172 offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1; 1173 1174 start_marker_record->end_seq = tcp_sk(sk)->write_seq; 1175 start_marker_record->len = 0; 1176 start_marker_record->num_frags = 0; 1177 1178 INIT_WORK(&offload_ctx->destruct_work, tls_device_tx_del_task); 1179 offload_ctx->ctx = ctx; 1180 1181 INIT_LIST_HEAD(&offload_ctx->records_list); 1182 list_add_tail(&start_marker_record->list, &offload_ctx->records_list); 1183 spin_lock_init(&offload_ctx->lock); 1184 sg_init_table(offload_ctx->sg_tx_data, 1185 ARRAY_SIZE(offload_ctx->sg_tx_data)); 1186 1187 clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked); 1188 ctx->push_pending_record = tls_device_push_pending_record; 1189 1190 /* TLS offload is greatly simplified if we don't send 1191 * SKBs where only part of the payload needs to be encrypted. 1192 * So mark the last skb in the write queue as end of record. 1193 */ 1194 skb = tcp_write_queue_tail(sk); 1195 if (skb) 1196 TCP_SKB_CB(skb)->eor = 1; 1197 1198 /* Avoid offloading if the device is down 1199 * We don't want to offload new flows after 1200 * the NETDEV_DOWN event 1201 * 1202 * device_offload_lock is taken in tls_devices's NETDEV_DOWN 1203 * handler thus protecting from the device going down before 1204 * ctx was added to tls_device_list. 1205 */ 1206 down_read(&device_offload_lock); 1207 if (!(netdev->flags & IFF_UP)) { 1208 rc = -EINVAL; 1209 goto release_lock; 1210 } 1211 1212 ctx->priv_ctx_tx = offload_ctx; 1213 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX, 1214 &ctx->crypto_send.info, 1215 tcp_sk(sk)->write_seq); 1216 trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX, 1217 tcp_sk(sk)->write_seq, rec_seq, rc); 1218 if (rc) 1219 goto release_lock; 1220 1221 tls_device_attach(ctx, sk, netdev); 1222 up_read(&device_offload_lock); 1223 1224 /* following this assignment tls_is_sk_tx_device_offloaded 1225 * will return true and the context might be accessed 1226 * by the netdev's xmit function. 1227 */ 1228 smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb); 1229 dev_put(netdev); 1230 1231 return 0; 1232 1233 release_lock: 1234 up_read(&device_offload_lock); 1235 clean_acked_data_disable(inet_csk(sk)); 1236 crypto_free_aead(offload_ctx->aead_send); 1237 free_offload_ctx: 1238 kfree(offload_ctx); 1239 ctx->priv_ctx_tx = NULL; 1240 free_marker_record: 1241 kfree(start_marker_record); 1242 free_rec_seq: 1243 kfree(ctx->tx.rec_seq); 1244 free_iv: 1245 kfree(ctx->tx.iv); 1246 release_netdev: 1247 dev_put(netdev); 1248 return rc; 1249 } 1250 1251 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx) 1252 { 1253 struct tls12_crypto_info_aes_gcm_128 *info; 1254 struct tls_offload_context_rx *context; 1255 struct net_device *netdev; 1256 int rc = 0; 1257 1258 if (ctx->crypto_recv.info.version != TLS_1_2_VERSION) 1259 return -EOPNOTSUPP; 1260 1261 netdev = get_netdev_for_sock(sk); 1262 if (!netdev) { 1263 pr_err_ratelimited("%s: netdev not found\n", __func__); 1264 return -EINVAL; 1265 } 1266 1267 if (!(netdev->features & NETIF_F_HW_TLS_RX)) { 1268 rc = -EOPNOTSUPP; 1269 goto release_netdev; 1270 } 1271 1272 /* Avoid offloading if the device is down 1273 * We don't want to offload new flows after 1274 * the NETDEV_DOWN event 1275 * 1276 * device_offload_lock is taken in tls_devices's NETDEV_DOWN 1277 * handler thus protecting from the device going down before 1278 * ctx was added to tls_device_list. 1279 */ 1280 down_read(&device_offload_lock); 1281 if (!(netdev->flags & IFF_UP)) { 1282 rc = -EINVAL; 1283 goto release_lock; 1284 } 1285 1286 context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL); 1287 if (!context) { 1288 rc = -ENOMEM; 1289 goto release_lock; 1290 } 1291 context->resync_nh_reset = 1; 1292 1293 ctx->priv_ctx_rx = context; 1294 rc = tls_set_sw_offload(sk, ctx, 0); 1295 if (rc) 1296 goto release_ctx; 1297 1298 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX, 1299 &ctx->crypto_recv.info, 1300 tcp_sk(sk)->copied_seq); 1301 info = (void *)&ctx->crypto_recv.info; 1302 trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX, 1303 tcp_sk(sk)->copied_seq, info->rec_seq, rc); 1304 if (rc) 1305 goto free_sw_resources; 1306 1307 tls_device_attach(ctx, sk, netdev); 1308 up_read(&device_offload_lock); 1309 1310 dev_put(netdev); 1311 1312 return 0; 1313 1314 free_sw_resources: 1315 up_read(&device_offload_lock); 1316 tls_sw_free_resources_rx(sk); 1317 down_read(&device_offload_lock); 1318 release_ctx: 1319 ctx->priv_ctx_rx = NULL; 1320 release_lock: 1321 up_read(&device_offload_lock); 1322 release_netdev: 1323 dev_put(netdev); 1324 return rc; 1325 } 1326 1327 void tls_device_offload_cleanup_rx(struct sock *sk) 1328 { 1329 struct tls_context *tls_ctx = tls_get_ctx(sk); 1330 struct net_device *netdev; 1331 1332 down_read(&device_offload_lock); 1333 netdev = rcu_dereference_protected(tls_ctx->netdev, 1334 lockdep_is_held(&device_offload_lock)); 1335 if (!netdev) 1336 goto out; 1337 1338 netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx, 1339 TLS_OFFLOAD_CTX_DIR_RX); 1340 1341 if (tls_ctx->tx_conf != TLS_HW) { 1342 dev_put(netdev); 1343 rcu_assign_pointer(tls_ctx->netdev, NULL); 1344 } else { 1345 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags); 1346 } 1347 out: 1348 up_read(&device_offload_lock); 1349 tls_sw_release_resources_rx(sk); 1350 } 1351 1352 static int tls_device_down(struct net_device *netdev) 1353 { 1354 struct tls_context *ctx, *tmp; 1355 unsigned long flags; 1356 LIST_HEAD(list); 1357 1358 /* Request a write lock to block new offload attempts */ 1359 down_write(&device_offload_lock); 1360 1361 spin_lock_irqsave(&tls_device_lock, flags); 1362 list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) { 1363 struct net_device *ctx_netdev = 1364 rcu_dereference_protected(ctx->netdev, 1365 lockdep_is_held(&device_offload_lock)); 1366 1367 if (ctx_netdev != netdev || 1368 !refcount_inc_not_zero(&ctx->refcount)) 1369 continue; 1370 1371 list_move(&ctx->list, &list); 1372 } 1373 spin_unlock_irqrestore(&tls_device_lock, flags); 1374 1375 list_for_each_entry_safe(ctx, tmp, &list, list) { 1376 /* Stop offloaded TX and switch to the fallback. 1377 * tls_is_sk_tx_device_offloaded will return false. 1378 */ 1379 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw); 1380 1381 /* Stop the RX and TX resync. 1382 * tls_dev_resync must not be called after tls_dev_del. 1383 */ 1384 rcu_assign_pointer(ctx->netdev, NULL); 1385 1386 /* Start skipping the RX resync logic completely. */ 1387 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags); 1388 1389 /* Sync with inflight packets. After this point: 1390 * TX: no non-encrypted packets will be passed to the driver. 1391 * RX: resync requests from the driver will be ignored. 1392 */ 1393 synchronize_net(); 1394 1395 /* Release the offload context on the driver side. */ 1396 if (ctx->tx_conf == TLS_HW) 1397 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 1398 TLS_OFFLOAD_CTX_DIR_TX); 1399 if (ctx->rx_conf == TLS_HW && 1400 !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags)) 1401 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 1402 TLS_OFFLOAD_CTX_DIR_RX); 1403 1404 dev_put(netdev); 1405 1406 /* Move the context to a separate list for two reasons: 1407 * 1. When the context is deallocated, list_del is called. 1408 * 2. It's no longer an offloaded context, so we don't want to 1409 * run offload-specific code on this context. 1410 */ 1411 spin_lock_irqsave(&tls_device_lock, flags); 1412 list_move_tail(&ctx->list, &tls_device_down_list); 1413 spin_unlock_irqrestore(&tls_device_lock, flags); 1414 1415 /* Device contexts for RX and TX will be freed in on sk_destruct 1416 * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW. 1417 * Now release the ref taken above. 1418 */ 1419 if (refcount_dec_and_test(&ctx->refcount)) { 1420 /* sk_destruct ran after tls_device_down took a ref, and 1421 * it returned early. Complete the destruction here. 1422 */ 1423 list_del(&ctx->list); 1424 tls_device_free_ctx(ctx); 1425 } 1426 } 1427 1428 up_write(&device_offload_lock); 1429 1430 flush_workqueue(destruct_wq); 1431 1432 return NOTIFY_DONE; 1433 } 1434 1435 static int tls_dev_event(struct notifier_block *this, unsigned long event, 1436 void *ptr) 1437 { 1438 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1439 1440 if (!dev->tlsdev_ops && 1441 !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX))) 1442 return NOTIFY_DONE; 1443 1444 switch (event) { 1445 case NETDEV_REGISTER: 1446 case NETDEV_FEAT_CHANGE: 1447 if (netif_is_bond_master(dev)) 1448 return NOTIFY_DONE; 1449 if ((dev->features & NETIF_F_HW_TLS_RX) && 1450 !dev->tlsdev_ops->tls_dev_resync) 1451 return NOTIFY_BAD; 1452 1453 if (dev->tlsdev_ops && 1454 dev->tlsdev_ops->tls_dev_add && 1455 dev->tlsdev_ops->tls_dev_del) 1456 return NOTIFY_DONE; 1457 else 1458 return NOTIFY_BAD; 1459 case NETDEV_DOWN: 1460 return tls_device_down(dev); 1461 } 1462 return NOTIFY_DONE; 1463 } 1464 1465 static struct notifier_block tls_dev_notifier = { 1466 .notifier_call = tls_dev_event, 1467 }; 1468 1469 int __init tls_device_init(void) 1470 { 1471 int err; 1472 1473 destruct_wq = alloc_workqueue("ktls_device_destruct", 0, 0); 1474 if (!destruct_wq) 1475 return -ENOMEM; 1476 1477 err = register_netdevice_notifier(&tls_dev_notifier); 1478 if (err) 1479 destroy_workqueue(destruct_wq); 1480 1481 return err; 1482 } 1483 1484 void __exit tls_device_cleanup(void) 1485 { 1486 unregister_netdevice_notifier(&tls_dev_notifier); 1487 destroy_workqueue(destruct_wq); 1488 clean_acked_data_flush(); 1489 } 1490