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); 511 512 iter_offset.offset += copy; 513 } else if (copy) { 514 copy = min_t(size_t, copy, pfrag->size - pfrag->offset); 515 516 rc = tls_device_copy_data(page_address(pfrag->page) + 517 pfrag->offset, copy, 518 iter_offset.msg_iter); 519 if (rc) 520 goto handle_error; 521 tls_append_frag(record, pfrag, copy); 522 } 523 524 size -= copy; 525 if (!size) { 526 last_record: 527 tls_push_record_flags = flags; 528 if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) { 529 more = true; 530 break; 531 } 532 533 done = true; 534 } 535 536 if (done || record->len >= max_open_record_len || 537 (record->num_frags >= MAX_SKB_FRAGS - 1)) { 538 rc = tls_device_record_close(sk, tls_ctx, record, 539 pfrag, record_type); 540 if (rc) { 541 if (rc > 0) { 542 size += rc; 543 } else { 544 size = orig_size; 545 destroy_record(record); 546 ctx->open_record = NULL; 547 break; 548 } 549 } 550 551 rc = tls_push_record(sk, 552 tls_ctx, 553 ctx, 554 record, 555 tls_push_record_flags); 556 if (rc < 0) 557 break; 558 } 559 } while (!done); 560 561 tls_ctx->pending_open_record_frags = more; 562 563 if (orig_size - size > 0) 564 rc = orig_size - size; 565 566 return rc; 567 } 568 569 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) 570 { 571 unsigned char record_type = TLS_RECORD_TYPE_DATA; 572 struct tls_context *tls_ctx = tls_get_ctx(sk); 573 union tls_iter_offset iter; 574 int rc; 575 576 mutex_lock(&tls_ctx->tx_lock); 577 lock_sock(sk); 578 579 if (unlikely(msg->msg_controllen)) { 580 rc = tls_process_cmsg(sk, msg, &record_type); 581 if (rc) 582 goto out; 583 } 584 585 iter.msg_iter = &msg->msg_iter; 586 rc = tls_push_data(sk, iter, size, msg->msg_flags, record_type, NULL); 587 588 out: 589 release_sock(sk); 590 mutex_unlock(&tls_ctx->tx_lock); 591 return rc; 592 } 593 594 int tls_device_sendpage(struct sock *sk, struct page *page, 595 int offset, size_t size, int flags) 596 { 597 struct tls_context *tls_ctx = tls_get_ctx(sk); 598 union tls_iter_offset iter_offset; 599 struct iov_iter msg_iter; 600 char *kaddr; 601 struct kvec iov; 602 int rc; 603 604 if (flags & MSG_SENDPAGE_NOTLAST) 605 flags |= MSG_MORE; 606 607 mutex_lock(&tls_ctx->tx_lock); 608 lock_sock(sk); 609 610 if (flags & MSG_OOB) { 611 rc = -EOPNOTSUPP; 612 goto out; 613 } 614 615 if (tls_ctx->zerocopy_sendfile) { 616 iter_offset.offset = offset; 617 rc = tls_push_data(sk, iter_offset, size, 618 flags, TLS_RECORD_TYPE_DATA, page); 619 goto out; 620 } 621 622 kaddr = kmap(page); 623 iov.iov_base = kaddr + offset; 624 iov.iov_len = size; 625 iov_iter_kvec(&msg_iter, ITER_SOURCE, &iov, 1, size); 626 iter_offset.msg_iter = &msg_iter; 627 rc = tls_push_data(sk, iter_offset, size, flags, TLS_RECORD_TYPE_DATA, 628 NULL); 629 kunmap(page); 630 631 out: 632 release_sock(sk); 633 mutex_unlock(&tls_ctx->tx_lock); 634 return rc; 635 } 636 637 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 638 u32 seq, u64 *p_record_sn) 639 { 640 u64 record_sn = context->hint_record_sn; 641 struct tls_record_info *info, *last; 642 643 info = context->retransmit_hint; 644 if (!info || 645 before(seq, info->end_seq - info->len)) { 646 /* if retransmit_hint is irrelevant start 647 * from the beginning of the list 648 */ 649 info = list_first_entry_or_null(&context->records_list, 650 struct tls_record_info, list); 651 if (!info) 652 return NULL; 653 /* send the start_marker record if seq number is before the 654 * tls offload start marker sequence number. This record is 655 * required to handle TCP packets which are before TLS offload 656 * started. 657 * And if it's not start marker, look if this seq number 658 * belongs to the list. 659 */ 660 if (likely(!tls_record_is_start_marker(info))) { 661 /* we have the first record, get the last record to see 662 * if this seq number belongs to the list. 663 */ 664 last = list_last_entry(&context->records_list, 665 struct tls_record_info, list); 666 667 if (!between(seq, tls_record_start_seq(info), 668 last->end_seq)) 669 return NULL; 670 } 671 record_sn = context->unacked_record_sn; 672 } 673 674 /* We just need the _rcu for the READ_ONCE() */ 675 rcu_read_lock(); 676 list_for_each_entry_from_rcu(info, &context->records_list, list) { 677 if (before(seq, info->end_seq)) { 678 if (!context->retransmit_hint || 679 after(info->end_seq, 680 context->retransmit_hint->end_seq)) { 681 context->hint_record_sn = record_sn; 682 context->retransmit_hint = info; 683 } 684 *p_record_sn = record_sn; 685 goto exit_rcu_unlock; 686 } 687 record_sn++; 688 } 689 info = NULL; 690 691 exit_rcu_unlock: 692 rcu_read_unlock(); 693 return info; 694 } 695 EXPORT_SYMBOL(tls_get_record); 696 697 static int tls_device_push_pending_record(struct sock *sk, int flags) 698 { 699 union tls_iter_offset iter; 700 struct iov_iter msg_iter; 701 702 iov_iter_kvec(&msg_iter, ITER_SOURCE, NULL, 0, 0); 703 iter.msg_iter = &msg_iter; 704 return tls_push_data(sk, iter, 0, flags, TLS_RECORD_TYPE_DATA, NULL); 705 } 706 707 void tls_device_write_space(struct sock *sk, struct tls_context *ctx) 708 { 709 if (tls_is_partially_sent_record(ctx)) { 710 gfp_t sk_allocation = sk->sk_allocation; 711 712 WARN_ON_ONCE(sk->sk_write_pending); 713 714 sk->sk_allocation = GFP_ATOMIC; 715 tls_push_partial_record(sk, ctx, 716 MSG_DONTWAIT | MSG_NOSIGNAL | 717 MSG_SENDPAGE_DECRYPTED); 718 sk->sk_allocation = sk_allocation; 719 } 720 } 721 722 static void tls_device_resync_rx(struct tls_context *tls_ctx, 723 struct sock *sk, u32 seq, u8 *rcd_sn) 724 { 725 struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); 726 struct net_device *netdev; 727 728 trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type); 729 rcu_read_lock(); 730 netdev = rcu_dereference(tls_ctx->netdev); 731 if (netdev) 732 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn, 733 TLS_OFFLOAD_CTX_DIR_RX); 734 rcu_read_unlock(); 735 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC); 736 } 737 738 static bool 739 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async, 740 s64 resync_req, u32 *seq, u16 *rcd_delta) 741 { 742 u32 is_async = resync_req & RESYNC_REQ_ASYNC; 743 u32 req_seq = resync_req >> 32; 744 u32 req_end = req_seq + ((resync_req >> 16) & 0xffff); 745 u16 i; 746 747 *rcd_delta = 0; 748 749 if (is_async) { 750 /* shouldn't get to wraparound: 751 * too long in async stage, something bad happened 752 */ 753 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX)) 754 return false; 755 756 /* asynchronous stage: log all headers seq such that 757 * req_seq <= seq <= end_seq, and wait for real resync request 758 */ 759 if (before(*seq, req_seq)) 760 return false; 761 if (!after(*seq, req_end) && 762 resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX) 763 resync_async->log[resync_async->loglen++] = *seq; 764 765 resync_async->rcd_delta++; 766 767 return false; 768 } 769 770 /* synchronous stage: check against the logged entries and 771 * proceed to check the next entries if no match was found 772 */ 773 for (i = 0; i < resync_async->loglen; i++) 774 if (req_seq == resync_async->log[i] && 775 atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) { 776 *rcd_delta = resync_async->rcd_delta - i; 777 *seq = req_seq; 778 resync_async->loglen = 0; 779 resync_async->rcd_delta = 0; 780 return true; 781 } 782 783 resync_async->loglen = 0; 784 resync_async->rcd_delta = 0; 785 786 if (req_seq == *seq && 787 atomic64_try_cmpxchg(&resync_async->req, 788 &resync_req, 0)) 789 return true; 790 791 return false; 792 } 793 794 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq) 795 { 796 struct tls_context *tls_ctx = tls_get_ctx(sk); 797 struct tls_offload_context_rx *rx_ctx; 798 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; 799 u32 sock_data, is_req_pending; 800 struct tls_prot_info *prot; 801 s64 resync_req; 802 u16 rcd_delta; 803 u32 req_seq; 804 805 if (tls_ctx->rx_conf != TLS_HW) 806 return; 807 if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) 808 return; 809 810 prot = &tls_ctx->prot_info; 811 rx_ctx = tls_offload_ctx_rx(tls_ctx); 812 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); 813 814 switch (rx_ctx->resync_type) { 815 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ: 816 resync_req = atomic64_read(&rx_ctx->resync_req); 817 req_seq = resync_req >> 32; 818 seq += TLS_HEADER_SIZE - 1; 819 is_req_pending = resync_req; 820 821 if (likely(!is_req_pending) || req_seq != seq || 822 !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0)) 823 return; 824 break; 825 case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT: 826 if (likely(!rx_ctx->resync_nh_do_now)) 827 return; 828 829 /* head of next rec is already in, note that the sock_inq will 830 * include the currently parsed message when called from parser 831 */ 832 sock_data = tcp_inq(sk); 833 if (sock_data > rcd_len) { 834 trace_tls_device_rx_resync_nh_delay(sk, sock_data, 835 rcd_len); 836 return; 837 } 838 839 rx_ctx->resync_nh_do_now = 0; 840 seq += rcd_len; 841 tls_bigint_increment(rcd_sn, prot->rec_seq_size); 842 break; 843 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC: 844 resync_req = atomic64_read(&rx_ctx->resync_async->req); 845 is_req_pending = resync_req; 846 if (likely(!is_req_pending)) 847 return; 848 849 if (!tls_device_rx_resync_async(rx_ctx->resync_async, 850 resync_req, &seq, &rcd_delta)) 851 return; 852 tls_bigint_subtract(rcd_sn, rcd_delta); 853 break; 854 } 855 856 tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn); 857 } 858 859 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx, 860 struct tls_offload_context_rx *ctx, 861 struct sock *sk, struct sk_buff *skb) 862 { 863 struct strp_msg *rxm; 864 865 /* device will request resyncs by itself based on stream scan */ 866 if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT) 867 return; 868 /* already scheduled */ 869 if (ctx->resync_nh_do_now) 870 return; 871 /* seen decrypted fragments since last fully-failed record */ 872 if (ctx->resync_nh_reset) { 873 ctx->resync_nh_reset = 0; 874 ctx->resync_nh.decrypted_failed = 1; 875 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL; 876 return; 877 } 878 879 if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt) 880 return; 881 882 /* doing resync, bump the next target in case it fails */ 883 if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL) 884 ctx->resync_nh.decrypted_tgt *= 2; 885 else 886 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL; 887 888 rxm = strp_msg(skb); 889 890 /* head of next rec is already in, parser will sync for us */ 891 if (tcp_inq(sk) > rxm->full_len) { 892 trace_tls_device_rx_resync_nh_schedule(sk); 893 ctx->resync_nh_do_now = 1; 894 } else { 895 struct tls_prot_info *prot = &tls_ctx->prot_info; 896 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; 897 898 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); 899 tls_bigint_increment(rcd_sn, prot->rec_seq_size); 900 901 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq, 902 rcd_sn); 903 } 904 } 905 906 static int 907 tls_device_reencrypt(struct sock *sk, struct tls_context *tls_ctx) 908 { 909 struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx); 910 const struct tls_cipher_size_desc *cipher_sz; 911 int err, offset, copy, data_len, pos; 912 struct sk_buff *skb, *skb_iter; 913 struct scatterlist sg[1]; 914 struct strp_msg *rxm; 915 char *orig_buf, *buf; 916 917 switch (tls_ctx->crypto_recv.info.cipher_type) { 918 case TLS_CIPHER_AES_GCM_128: 919 case TLS_CIPHER_AES_GCM_256: 920 break; 921 default: 922 return -EINVAL; 923 } 924 cipher_sz = &tls_cipher_size_desc[tls_ctx->crypto_recv.info.cipher_type]; 925 926 rxm = strp_msg(tls_strp_msg(sw_ctx)); 927 orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv, 928 sk->sk_allocation); 929 if (!orig_buf) 930 return -ENOMEM; 931 buf = orig_buf; 932 933 err = tls_strp_msg_cow(sw_ctx); 934 if (unlikely(err)) 935 goto free_buf; 936 937 skb = tls_strp_msg(sw_ctx); 938 rxm = strp_msg(skb); 939 offset = rxm->offset; 940 941 sg_init_table(sg, 1); 942 sg_set_buf(&sg[0], buf, 943 rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv); 944 err = skb_copy_bits(skb, offset, buf, TLS_HEADER_SIZE + cipher_sz->iv); 945 if (err) 946 goto free_buf; 947 948 /* We are interested only in the decrypted data not the auth */ 949 err = decrypt_skb(sk, sg); 950 if (err != -EBADMSG) 951 goto free_buf; 952 else 953 err = 0; 954 955 data_len = rxm->full_len - cipher_sz->tag; 956 957 if (skb_pagelen(skb) > offset) { 958 copy = min_t(int, skb_pagelen(skb) - offset, data_len); 959 960 if (skb->decrypted) { 961 err = skb_store_bits(skb, offset, buf, copy); 962 if (err) 963 goto free_buf; 964 } 965 966 offset += copy; 967 buf += copy; 968 } 969 970 pos = skb_pagelen(skb); 971 skb_walk_frags(skb, skb_iter) { 972 int frag_pos; 973 974 /* Practically all frags must belong to msg if reencrypt 975 * is needed with current strparser and coalescing logic, 976 * but strparser may "get optimized", so let's be safe. 977 */ 978 if (pos + skb_iter->len <= offset) 979 goto done_with_frag; 980 if (pos >= data_len + rxm->offset) 981 break; 982 983 frag_pos = offset - pos; 984 copy = min_t(int, skb_iter->len - frag_pos, 985 data_len + rxm->offset - offset); 986 987 if (skb_iter->decrypted) { 988 err = skb_store_bits(skb_iter, frag_pos, buf, copy); 989 if (err) 990 goto free_buf; 991 } 992 993 offset += copy; 994 buf += copy; 995 done_with_frag: 996 pos += skb_iter->len; 997 } 998 999 free_buf: 1000 kfree(orig_buf); 1001 return err; 1002 } 1003 1004 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx) 1005 { 1006 struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx); 1007 struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx); 1008 struct sk_buff *skb = tls_strp_msg(sw_ctx); 1009 struct strp_msg *rxm = strp_msg(skb); 1010 int is_decrypted = skb->decrypted; 1011 int is_encrypted = !is_decrypted; 1012 struct sk_buff *skb_iter; 1013 int left; 1014 1015 left = rxm->full_len - skb->len; 1016 /* Check if all the data is decrypted already */ 1017 skb_iter = skb_shinfo(skb)->frag_list; 1018 while (skb_iter && left > 0) { 1019 is_decrypted &= skb_iter->decrypted; 1020 is_encrypted &= !skb_iter->decrypted; 1021 1022 left -= skb_iter->len; 1023 skb_iter = skb_iter->next; 1024 } 1025 1026 trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len, 1027 tls_ctx->rx.rec_seq, rxm->full_len, 1028 is_encrypted, is_decrypted); 1029 1030 if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) { 1031 if (likely(is_encrypted || is_decrypted)) 1032 return is_decrypted; 1033 1034 /* After tls_device_down disables the offload, the next SKB will 1035 * likely have initial fragments decrypted, and final ones not 1036 * decrypted. We need to reencrypt that single SKB. 1037 */ 1038 return tls_device_reencrypt(sk, tls_ctx); 1039 } 1040 1041 /* Return immediately if the record is either entirely plaintext or 1042 * entirely ciphertext. Otherwise handle reencrypt partially decrypted 1043 * record. 1044 */ 1045 if (is_decrypted) { 1046 ctx->resync_nh_reset = 1; 1047 return is_decrypted; 1048 } 1049 if (is_encrypted) { 1050 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb); 1051 return 0; 1052 } 1053 1054 ctx->resync_nh_reset = 1; 1055 return tls_device_reencrypt(sk, tls_ctx); 1056 } 1057 1058 static void tls_device_attach(struct tls_context *ctx, struct sock *sk, 1059 struct net_device *netdev) 1060 { 1061 if (sk->sk_destruct != tls_device_sk_destruct) { 1062 refcount_set(&ctx->refcount, 1); 1063 dev_hold(netdev); 1064 RCU_INIT_POINTER(ctx->netdev, netdev); 1065 spin_lock_irq(&tls_device_lock); 1066 list_add_tail(&ctx->list, &tls_device_list); 1067 spin_unlock_irq(&tls_device_lock); 1068 1069 ctx->sk_destruct = sk->sk_destruct; 1070 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct); 1071 } 1072 } 1073 1074 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx) 1075 { 1076 struct tls_context *tls_ctx = tls_get_ctx(sk); 1077 struct tls_prot_info *prot = &tls_ctx->prot_info; 1078 const struct tls_cipher_size_desc *cipher_sz; 1079 struct tls_record_info *start_marker_record; 1080 struct tls_offload_context_tx *offload_ctx; 1081 struct tls_crypto_info *crypto_info; 1082 struct net_device *netdev; 1083 char *iv, *rec_seq; 1084 struct sk_buff *skb; 1085 __be64 rcd_sn; 1086 int rc; 1087 1088 if (!ctx) 1089 return -EINVAL; 1090 1091 if (ctx->priv_ctx_tx) 1092 return -EEXIST; 1093 1094 netdev = get_netdev_for_sock(sk); 1095 if (!netdev) { 1096 pr_err_ratelimited("%s: netdev not found\n", __func__); 1097 return -EINVAL; 1098 } 1099 1100 if (!(netdev->features & NETIF_F_HW_TLS_TX)) { 1101 rc = -EOPNOTSUPP; 1102 goto release_netdev; 1103 } 1104 1105 crypto_info = &ctx->crypto_send.info; 1106 if (crypto_info->version != TLS_1_2_VERSION) { 1107 rc = -EOPNOTSUPP; 1108 goto release_netdev; 1109 } 1110 1111 switch (crypto_info->cipher_type) { 1112 case TLS_CIPHER_AES_GCM_128: 1113 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv; 1114 rec_seq = 1115 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq; 1116 break; 1117 case TLS_CIPHER_AES_GCM_256: 1118 iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv; 1119 rec_seq = 1120 ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq; 1121 break; 1122 default: 1123 rc = -EINVAL; 1124 goto release_netdev; 1125 } 1126 cipher_sz = &tls_cipher_size_desc[crypto_info->cipher_type]; 1127 1128 /* Sanity-check the rec_seq_size for stack allocations */ 1129 if (cipher_sz->rec_seq > TLS_MAX_REC_SEQ_SIZE) { 1130 rc = -EINVAL; 1131 goto release_netdev; 1132 } 1133 1134 prot->version = crypto_info->version; 1135 prot->cipher_type = crypto_info->cipher_type; 1136 prot->prepend_size = TLS_HEADER_SIZE + cipher_sz->iv; 1137 prot->tag_size = cipher_sz->tag; 1138 prot->overhead_size = prot->prepend_size + prot->tag_size; 1139 prot->iv_size = cipher_sz->iv; 1140 prot->salt_size = cipher_sz->salt; 1141 ctx->tx.iv = kmalloc(cipher_sz->iv + cipher_sz->salt, GFP_KERNEL); 1142 if (!ctx->tx.iv) { 1143 rc = -ENOMEM; 1144 goto release_netdev; 1145 } 1146 1147 memcpy(ctx->tx.iv + cipher_sz->salt, iv, cipher_sz->iv); 1148 1149 prot->rec_seq_size = cipher_sz->rec_seq; 1150 ctx->tx.rec_seq = kmemdup(rec_seq, cipher_sz->rec_seq, GFP_KERNEL); 1151 if (!ctx->tx.rec_seq) { 1152 rc = -ENOMEM; 1153 goto free_iv; 1154 } 1155 1156 start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL); 1157 if (!start_marker_record) { 1158 rc = -ENOMEM; 1159 goto free_rec_seq; 1160 } 1161 1162 offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL); 1163 if (!offload_ctx) { 1164 rc = -ENOMEM; 1165 goto free_marker_record; 1166 } 1167 1168 rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info); 1169 if (rc) 1170 goto free_offload_ctx; 1171 1172 /* start at rec_seq - 1 to account for the start marker record */ 1173 memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn)); 1174 offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1; 1175 1176 start_marker_record->end_seq = tcp_sk(sk)->write_seq; 1177 start_marker_record->len = 0; 1178 start_marker_record->num_frags = 0; 1179 1180 INIT_WORK(&offload_ctx->destruct_work, tls_device_tx_del_task); 1181 offload_ctx->ctx = ctx; 1182 1183 INIT_LIST_HEAD(&offload_ctx->records_list); 1184 list_add_tail(&start_marker_record->list, &offload_ctx->records_list); 1185 spin_lock_init(&offload_ctx->lock); 1186 sg_init_table(offload_ctx->sg_tx_data, 1187 ARRAY_SIZE(offload_ctx->sg_tx_data)); 1188 1189 clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked); 1190 ctx->push_pending_record = tls_device_push_pending_record; 1191 1192 /* TLS offload is greatly simplified if we don't send 1193 * SKBs where only part of the payload needs to be encrypted. 1194 * So mark the last skb in the write queue as end of record. 1195 */ 1196 skb = tcp_write_queue_tail(sk); 1197 if (skb) 1198 TCP_SKB_CB(skb)->eor = 1; 1199 1200 /* Avoid offloading if the device is down 1201 * We don't want to offload new flows after 1202 * the NETDEV_DOWN event 1203 * 1204 * device_offload_lock is taken in tls_devices's NETDEV_DOWN 1205 * handler thus protecting from the device going down before 1206 * ctx was added to tls_device_list. 1207 */ 1208 down_read(&device_offload_lock); 1209 if (!(netdev->flags & IFF_UP)) { 1210 rc = -EINVAL; 1211 goto release_lock; 1212 } 1213 1214 ctx->priv_ctx_tx = offload_ctx; 1215 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX, 1216 &ctx->crypto_send.info, 1217 tcp_sk(sk)->write_seq); 1218 trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX, 1219 tcp_sk(sk)->write_seq, rec_seq, rc); 1220 if (rc) 1221 goto release_lock; 1222 1223 tls_device_attach(ctx, sk, netdev); 1224 up_read(&device_offload_lock); 1225 1226 /* following this assignment tls_is_sk_tx_device_offloaded 1227 * will return true and the context might be accessed 1228 * by the netdev's xmit function. 1229 */ 1230 smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb); 1231 dev_put(netdev); 1232 1233 return 0; 1234 1235 release_lock: 1236 up_read(&device_offload_lock); 1237 clean_acked_data_disable(inet_csk(sk)); 1238 crypto_free_aead(offload_ctx->aead_send); 1239 free_offload_ctx: 1240 kfree(offload_ctx); 1241 ctx->priv_ctx_tx = NULL; 1242 free_marker_record: 1243 kfree(start_marker_record); 1244 free_rec_seq: 1245 kfree(ctx->tx.rec_seq); 1246 free_iv: 1247 kfree(ctx->tx.iv); 1248 release_netdev: 1249 dev_put(netdev); 1250 return rc; 1251 } 1252 1253 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx) 1254 { 1255 struct tls12_crypto_info_aes_gcm_128 *info; 1256 struct tls_offload_context_rx *context; 1257 struct net_device *netdev; 1258 int rc = 0; 1259 1260 if (ctx->crypto_recv.info.version != TLS_1_2_VERSION) 1261 return -EOPNOTSUPP; 1262 1263 netdev = get_netdev_for_sock(sk); 1264 if (!netdev) { 1265 pr_err_ratelimited("%s: netdev not found\n", __func__); 1266 return -EINVAL; 1267 } 1268 1269 if (!(netdev->features & NETIF_F_HW_TLS_RX)) { 1270 rc = -EOPNOTSUPP; 1271 goto release_netdev; 1272 } 1273 1274 /* Avoid offloading if the device is down 1275 * We don't want to offload new flows after 1276 * the NETDEV_DOWN event 1277 * 1278 * device_offload_lock is taken in tls_devices's NETDEV_DOWN 1279 * handler thus protecting from the device going down before 1280 * ctx was added to tls_device_list. 1281 */ 1282 down_read(&device_offload_lock); 1283 if (!(netdev->flags & IFF_UP)) { 1284 rc = -EINVAL; 1285 goto release_lock; 1286 } 1287 1288 context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL); 1289 if (!context) { 1290 rc = -ENOMEM; 1291 goto release_lock; 1292 } 1293 context->resync_nh_reset = 1; 1294 1295 ctx->priv_ctx_rx = context; 1296 rc = tls_set_sw_offload(sk, ctx, 0); 1297 if (rc) 1298 goto release_ctx; 1299 1300 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX, 1301 &ctx->crypto_recv.info, 1302 tcp_sk(sk)->copied_seq); 1303 info = (void *)&ctx->crypto_recv.info; 1304 trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX, 1305 tcp_sk(sk)->copied_seq, info->rec_seq, rc); 1306 if (rc) 1307 goto free_sw_resources; 1308 1309 tls_device_attach(ctx, sk, netdev); 1310 up_read(&device_offload_lock); 1311 1312 dev_put(netdev); 1313 1314 return 0; 1315 1316 free_sw_resources: 1317 up_read(&device_offload_lock); 1318 tls_sw_free_resources_rx(sk); 1319 down_read(&device_offload_lock); 1320 release_ctx: 1321 ctx->priv_ctx_rx = NULL; 1322 release_lock: 1323 up_read(&device_offload_lock); 1324 release_netdev: 1325 dev_put(netdev); 1326 return rc; 1327 } 1328 1329 void tls_device_offload_cleanup_rx(struct sock *sk) 1330 { 1331 struct tls_context *tls_ctx = tls_get_ctx(sk); 1332 struct net_device *netdev; 1333 1334 down_read(&device_offload_lock); 1335 netdev = rcu_dereference_protected(tls_ctx->netdev, 1336 lockdep_is_held(&device_offload_lock)); 1337 if (!netdev) 1338 goto out; 1339 1340 netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx, 1341 TLS_OFFLOAD_CTX_DIR_RX); 1342 1343 if (tls_ctx->tx_conf != TLS_HW) { 1344 dev_put(netdev); 1345 rcu_assign_pointer(tls_ctx->netdev, NULL); 1346 } else { 1347 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags); 1348 } 1349 out: 1350 up_read(&device_offload_lock); 1351 tls_sw_release_resources_rx(sk); 1352 } 1353 1354 static int tls_device_down(struct net_device *netdev) 1355 { 1356 struct tls_context *ctx, *tmp; 1357 unsigned long flags; 1358 LIST_HEAD(list); 1359 1360 /* Request a write lock to block new offload attempts */ 1361 down_write(&device_offload_lock); 1362 1363 spin_lock_irqsave(&tls_device_lock, flags); 1364 list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) { 1365 struct net_device *ctx_netdev = 1366 rcu_dereference_protected(ctx->netdev, 1367 lockdep_is_held(&device_offload_lock)); 1368 1369 if (ctx_netdev != netdev || 1370 !refcount_inc_not_zero(&ctx->refcount)) 1371 continue; 1372 1373 list_move(&ctx->list, &list); 1374 } 1375 spin_unlock_irqrestore(&tls_device_lock, flags); 1376 1377 list_for_each_entry_safe(ctx, tmp, &list, list) { 1378 /* Stop offloaded TX and switch to the fallback. 1379 * tls_is_sk_tx_device_offloaded will return false. 1380 */ 1381 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw); 1382 1383 /* Stop the RX and TX resync. 1384 * tls_dev_resync must not be called after tls_dev_del. 1385 */ 1386 rcu_assign_pointer(ctx->netdev, NULL); 1387 1388 /* Start skipping the RX resync logic completely. */ 1389 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags); 1390 1391 /* Sync with inflight packets. After this point: 1392 * TX: no non-encrypted packets will be passed to the driver. 1393 * RX: resync requests from the driver will be ignored. 1394 */ 1395 synchronize_net(); 1396 1397 /* Release the offload context on the driver side. */ 1398 if (ctx->tx_conf == TLS_HW) 1399 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 1400 TLS_OFFLOAD_CTX_DIR_TX); 1401 if (ctx->rx_conf == TLS_HW && 1402 !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags)) 1403 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 1404 TLS_OFFLOAD_CTX_DIR_RX); 1405 1406 dev_put(netdev); 1407 1408 /* Move the context to a separate list for two reasons: 1409 * 1. When the context is deallocated, list_del is called. 1410 * 2. It's no longer an offloaded context, so we don't want to 1411 * run offload-specific code on this context. 1412 */ 1413 spin_lock_irqsave(&tls_device_lock, flags); 1414 list_move_tail(&ctx->list, &tls_device_down_list); 1415 spin_unlock_irqrestore(&tls_device_lock, flags); 1416 1417 /* Device contexts for RX and TX will be freed in on sk_destruct 1418 * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW. 1419 * Now release the ref taken above. 1420 */ 1421 if (refcount_dec_and_test(&ctx->refcount)) { 1422 /* sk_destruct ran after tls_device_down took a ref, and 1423 * it returned early. Complete the destruction here. 1424 */ 1425 list_del(&ctx->list); 1426 tls_device_free_ctx(ctx); 1427 } 1428 } 1429 1430 up_write(&device_offload_lock); 1431 1432 flush_workqueue(destruct_wq); 1433 1434 return NOTIFY_DONE; 1435 } 1436 1437 static int tls_dev_event(struct notifier_block *this, unsigned long event, 1438 void *ptr) 1439 { 1440 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1441 1442 if (!dev->tlsdev_ops && 1443 !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX))) 1444 return NOTIFY_DONE; 1445 1446 switch (event) { 1447 case NETDEV_REGISTER: 1448 case NETDEV_FEAT_CHANGE: 1449 if (netif_is_bond_master(dev)) 1450 return NOTIFY_DONE; 1451 if ((dev->features & NETIF_F_HW_TLS_RX) && 1452 !dev->tlsdev_ops->tls_dev_resync) 1453 return NOTIFY_BAD; 1454 1455 if (dev->tlsdev_ops && 1456 dev->tlsdev_ops->tls_dev_add && 1457 dev->tlsdev_ops->tls_dev_del) 1458 return NOTIFY_DONE; 1459 else 1460 return NOTIFY_BAD; 1461 case NETDEV_DOWN: 1462 return tls_device_down(dev); 1463 } 1464 return NOTIFY_DONE; 1465 } 1466 1467 static struct notifier_block tls_dev_notifier = { 1468 .notifier_call = tls_dev_event, 1469 }; 1470 1471 int __init tls_device_init(void) 1472 { 1473 int err; 1474 1475 destruct_wq = alloc_workqueue("ktls_device_destruct", 0, 0); 1476 if (!destruct_wq) 1477 return -ENOMEM; 1478 1479 err = register_netdevice_notifier(&tls_dev_notifier); 1480 if (err) 1481 destroy_workqueue(destruct_wq); 1482 1483 return err; 1484 } 1485 1486 void __exit tls_device_cleanup(void) 1487 { 1488 unregister_netdevice_notifier(&tls_dev_notifier); 1489 destroy_workqueue(destruct_wq); 1490 clean_acked_data_flush(); 1491 } 1492