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