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 /* device_offload_lock is used to synchronize tls_dev_add 42 * against NETDEV_DOWN notifications. 43 */ 44 static DECLARE_RWSEM(device_offload_lock); 45 46 static void tls_device_gc_task(struct work_struct *work); 47 48 static DECLARE_WORK(tls_device_gc_work, tls_device_gc_task); 49 static LIST_HEAD(tls_device_gc_list); 50 static LIST_HEAD(tls_device_list); 51 static DEFINE_SPINLOCK(tls_device_lock); 52 53 static void tls_device_free_ctx(struct tls_context *ctx) 54 { 55 if (ctx->tx_conf == TLS_HW) { 56 kfree(tls_offload_ctx_tx(ctx)); 57 kfree(ctx->tx.rec_seq); 58 kfree(ctx->tx.iv); 59 } 60 61 if (ctx->rx_conf == TLS_HW) 62 kfree(tls_offload_ctx_rx(ctx)); 63 64 tls_ctx_free(NULL, ctx); 65 } 66 67 static void tls_device_gc_task(struct work_struct *work) 68 { 69 struct tls_context *ctx, *tmp; 70 unsigned long flags; 71 LIST_HEAD(gc_list); 72 73 spin_lock_irqsave(&tls_device_lock, flags); 74 list_splice_init(&tls_device_gc_list, &gc_list); 75 spin_unlock_irqrestore(&tls_device_lock, flags); 76 77 list_for_each_entry_safe(ctx, tmp, &gc_list, list) { 78 struct net_device *netdev = ctx->netdev; 79 80 if (netdev && ctx->tx_conf == TLS_HW) { 81 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 82 TLS_OFFLOAD_CTX_DIR_TX); 83 dev_put(netdev); 84 ctx->netdev = NULL; 85 } 86 87 list_del(&ctx->list); 88 tls_device_free_ctx(ctx); 89 } 90 } 91 92 static void tls_device_queue_ctx_destruction(struct tls_context *ctx) 93 { 94 unsigned long flags; 95 96 spin_lock_irqsave(&tls_device_lock, flags); 97 list_move_tail(&ctx->list, &tls_device_gc_list); 98 99 /* schedule_work inside the spinlock 100 * to make sure tls_device_down waits for that work. 101 */ 102 schedule_work(&tls_device_gc_work); 103 104 spin_unlock_irqrestore(&tls_device_lock, flags); 105 } 106 107 /* We assume that the socket is already connected */ 108 static struct net_device *get_netdev_for_sock(struct sock *sk) 109 { 110 struct dst_entry *dst = sk_dst_get(sk); 111 struct net_device *netdev = NULL; 112 113 if (likely(dst)) { 114 netdev = dst->dev; 115 dev_hold(netdev); 116 } 117 118 dst_release(dst); 119 120 return netdev; 121 } 122 123 static void destroy_record(struct tls_record_info *record) 124 { 125 int i; 126 127 for (i = 0; i < record->num_frags; i++) 128 __skb_frag_unref(&record->frags[i]); 129 kfree(record); 130 } 131 132 static void delete_all_records(struct tls_offload_context_tx *offload_ctx) 133 { 134 struct tls_record_info *info, *temp; 135 136 list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) { 137 list_del(&info->list); 138 destroy_record(info); 139 } 140 141 offload_ctx->retransmit_hint = NULL; 142 } 143 144 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq) 145 { 146 struct tls_context *tls_ctx = tls_get_ctx(sk); 147 struct tls_record_info *info, *temp; 148 struct tls_offload_context_tx *ctx; 149 u64 deleted_records = 0; 150 unsigned long flags; 151 152 if (!tls_ctx) 153 return; 154 155 ctx = tls_offload_ctx_tx(tls_ctx); 156 157 spin_lock_irqsave(&ctx->lock, flags); 158 info = ctx->retransmit_hint; 159 if (info && !before(acked_seq, info->end_seq)) 160 ctx->retransmit_hint = NULL; 161 162 list_for_each_entry_safe(info, temp, &ctx->records_list, list) { 163 if (before(acked_seq, info->end_seq)) 164 break; 165 list_del(&info->list); 166 167 destroy_record(info); 168 deleted_records++; 169 } 170 171 ctx->unacked_record_sn += deleted_records; 172 spin_unlock_irqrestore(&ctx->lock, flags); 173 } 174 175 /* At this point, there should be no references on this 176 * socket and no in-flight SKBs associated with this 177 * socket, so it is safe to free all the resources. 178 */ 179 static void tls_device_sk_destruct(struct sock *sk) 180 { 181 struct tls_context *tls_ctx = tls_get_ctx(sk); 182 struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx); 183 184 tls_ctx->sk_destruct(sk); 185 186 if (tls_ctx->tx_conf == TLS_HW) { 187 if (ctx->open_record) 188 destroy_record(ctx->open_record); 189 delete_all_records(ctx); 190 crypto_free_aead(ctx->aead_send); 191 clean_acked_data_disable(inet_csk(sk)); 192 } 193 194 if (refcount_dec_and_test(&tls_ctx->refcount)) 195 tls_device_queue_ctx_destruction(tls_ctx); 196 } 197 198 void tls_device_free_resources_tx(struct sock *sk) 199 { 200 struct tls_context *tls_ctx = tls_get_ctx(sk); 201 202 tls_free_partial_record(sk, tls_ctx); 203 } 204 205 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx, 206 u32 seq) 207 { 208 struct net_device *netdev; 209 struct sk_buff *skb; 210 int err = 0; 211 u8 *rcd_sn; 212 213 skb = tcp_write_queue_tail(sk); 214 if (skb) 215 TCP_SKB_CB(skb)->eor = 1; 216 217 rcd_sn = tls_ctx->tx.rec_seq; 218 219 down_read(&device_offload_lock); 220 netdev = tls_ctx->netdev; 221 if (netdev) 222 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, 223 rcd_sn, 224 TLS_OFFLOAD_CTX_DIR_TX); 225 up_read(&device_offload_lock); 226 if (err) 227 return; 228 229 clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags); 230 } 231 232 static void tls_append_frag(struct tls_record_info *record, 233 struct page_frag *pfrag, 234 int size) 235 { 236 skb_frag_t *frag; 237 238 frag = &record->frags[record->num_frags - 1]; 239 if (skb_frag_page(frag) == pfrag->page && 240 skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) { 241 skb_frag_size_add(frag, size); 242 } else { 243 ++frag; 244 __skb_frag_set_page(frag, pfrag->page); 245 skb_frag_off_set(frag, pfrag->offset); 246 skb_frag_size_set(frag, size); 247 ++record->num_frags; 248 get_page(pfrag->page); 249 } 250 251 pfrag->offset += size; 252 record->len += size; 253 } 254 255 static int tls_push_record(struct sock *sk, 256 struct tls_context *ctx, 257 struct tls_offload_context_tx *offload_ctx, 258 struct tls_record_info *record, 259 int flags) 260 { 261 struct tls_prot_info *prot = &ctx->prot_info; 262 struct tcp_sock *tp = tcp_sk(sk); 263 skb_frag_t *frag; 264 int i; 265 266 record->end_seq = tp->write_seq + record->len; 267 list_add_tail_rcu(&record->list, &offload_ctx->records_list); 268 offload_ctx->open_record = NULL; 269 270 if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags)) 271 tls_device_resync_tx(sk, ctx, tp->write_seq); 272 273 tls_advance_record_sn(sk, prot, &ctx->tx); 274 275 for (i = 0; i < record->num_frags; i++) { 276 frag = &record->frags[i]; 277 sg_unmark_end(&offload_ctx->sg_tx_data[i]); 278 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag), 279 skb_frag_size(frag), skb_frag_off(frag)); 280 sk_mem_charge(sk, skb_frag_size(frag)); 281 get_page(skb_frag_page(frag)); 282 } 283 sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]); 284 285 /* all ready, send */ 286 return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags); 287 } 288 289 static int tls_device_record_close(struct sock *sk, 290 struct tls_context *ctx, 291 struct tls_record_info *record, 292 struct page_frag *pfrag, 293 unsigned char record_type) 294 { 295 struct tls_prot_info *prot = &ctx->prot_info; 296 int ret; 297 298 /* append tag 299 * device will fill in the tag, we just need to append a placeholder 300 * use socket memory to improve coalescing (re-using a single buffer 301 * increases frag count) 302 * if we can't allocate memory now, steal some back from data 303 */ 304 if (likely(skb_page_frag_refill(prot->tag_size, pfrag, 305 sk->sk_allocation))) { 306 ret = 0; 307 tls_append_frag(record, pfrag, prot->tag_size); 308 } else { 309 ret = prot->tag_size; 310 if (record->len <= prot->overhead_size) 311 return -ENOMEM; 312 } 313 314 /* fill prepend */ 315 tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]), 316 record->len - prot->overhead_size, 317 record_type, prot->version); 318 return ret; 319 } 320 321 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx, 322 struct page_frag *pfrag, 323 size_t prepend_size) 324 { 325 struct tls_record_info *record; 326 skb_frag_t *frag; 327 328 record = kmalloc(sizeof(*record), GFP_KERNEL); 329 if (!record) 330 return -ENOMEM; 331 332 frag = &record->frags[0]; 333 __skb_frag_set_page(frag, pfrag->page); 334 skb_frag_off_set(frag, pfrag->offset); 335 skb_frag_size_set(frag, prepend_size); 336 337 get_page(pfrag->page); 338 pfrag->offset += prepend_size; 339 340 record->num_frags = 1; 341 record->len = prepend_size; 342 offload_ctx->open_record = record; 343 return 0; 344 } 345 346 static int tls_do_allocation(struct sock *sk, 347 struct tls_offload_context_tx *offload_ctx, 348 struct page_frag *pfrag, 349 size_t prepend_size) 350 { 351 int ret; 352 353 if (!offload_ctx->open_record) { 354 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag, 355 sk->sk_allocation))) { 356 sk->sk_prot->enter_memory_pressure(sk); 357 sk_stream_moderate_sndbuf(sk); 358 return -ENOMEM; 359 } 360 361 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size); 362 if (ret) 363 return ret; 364 365 if (pfrag->size > pfrag->offset) 366 return 0; 367 } 368 369 if (!sk_page_frag_refill(sk, pfrag)) 370 return -ENOMEM; 371 372 return 0; 373 } 374 375 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i) 376 { 377 size_t pre_copy, nocache; 378 379 pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1); 380 if (pre_copy) { 381 pre_copy = min(pre_copy, bytes); 382 if (copy_from_iter(addr, pre_copy, i) != pre_copy) 383 return -EFAULT; 384 bytes -= pre_copy; 385 addr += pre_copy; 386 } 387 388 nocache = round_down(bytes, SMP_CACHE_BYTES); 389 if (copy_from_iter_nocache(addr, nocache, i) != nocache) 390 return -EFAULT; 391 bytes -= nocache; 392 addr += nocache; 393 394 if (bytes && copy_from_iter(addr, bytes, i) != bytes) 395 return -EFAULT; 396 397 return 0; 398 } 399 400 static int tls_push_data(struct sock *sk, 401 struct iov_iter *msg_iter, 402 size_t size, int flags, 403 unsigned char record_type) 404 { 405 struct tls_context *tls_ctx = tls_get_ctx(sk); 406 struct tls_prot_info *prot = &tls_ctx->prot_info; 407 struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx); 408 int more = flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE); 409 struct tls_record_info *record = ctx->open_record; 410 int tls_push_record_flags; 411 struct page_frag *pfrag; 412 size_t orig_size = size; 413 u32 max_open_record_len; 414 int copy, rc = 0; 415 bool done = false; 416 long timeo; 417 418 if (flags & 419 ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST)) 420 return -ENOTSUPP; 421 422 if (sk->sk_err) 423 return -sk->sk_err; 424 425 flags |= MSG_SENDPAGE_DECRYPTED; 426 tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST; 427 428 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); 429 if (tls_is_partially_sent_record(tls_ctx)) { 430 rc = tls_push_partial_record(sk, tls_ctx, flags); 431 if (rc < 0) 432 return rc; 433 } 434 435 pfrag = sk_page_frag(sk); 436 437 /* TLS_HEADER_SIZE is not counted as part of the TLS record, and 438 * we need to leave room for an authentication tag. 439 */ 440 max_open_record_len = TLS_MAX_PAYLOAD_SIZE + 441 prot->prepend_size; 442 do { 443 rc = tls_do_allocation(sk, ctx, pfrag, 444 prot->prepend_size); 445 if (rc) { 446 rc = sk_stream_wait_memory(sk, &timeo); 447 if (!rc) 448 continue; 449 450 record = ctx->open_record; 451 if (!record) 452 break; 453 handle_error: 454 if (record_type != TLS_RECORD_TYPE_DATA) { 455 /* avoid sending partial 456 * record with type != 457 * application_data 458 */ 459 size = orig_size; 460 destroy_record(record); 461 ctx->open_record = NULL; 462 } else if (record->len > prot->prepend_size) { 463 goto last_record; 464 } 465 466 break; 467 } 468 469 record = ctx->open_record; 470 copy = min_t(size_t, size, (pfrag->size - pfrag->offset)); 471 copy = min_t(size_t, copy, (max_open_record_len - record->len)); 472 473 rc = tls_device_copy_data(page_address(pfrag->page) + 474 pfrag->offset, copy, msg_iter); 475 if (rc) 476 goto handle_error; 477 tls_append_frag(record, pfrag, copy); 478 479 size -= copy; 480 if (!size) { 481 last_record: 482 tls_push_record_flags = flags; 483 if (more) { 484 tls_ctx->pending_open_record_frags = 485 !!record->num_frags; 486 break; 487 } 488 489 done = true; 490 } 491 492 if (done || record->len >= max_open_record_len || 493 (record->num_frags >= MAX_SKB_FRAGS - 1)) { 494 rc = tls_device_record_close(sk, tls_ctx, record, 495 pfrag, record_type); 496 if (rc) { 497 if (rc > 0) { 498 size += rc; 499 } else { 500 size = orig_size; 501 destroy_record(record); 502 ctx->open_record = NULL; 503 break; 504 } 505 } 506 507 rc = tls_push_record(sk, 508 tls_ctx, 509 ctx, 510 record, 511 tls_push_record_flags); 512 if (rc < 0) 513 break; 514 } 515 } while (!done); 516 517 if (orig_size - size > 0) 518 rc = orig_size - size; 519 520 return rc; 521 } 522 523 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) 524 { 525 unsigned char record_type = TLS_RECORD_TYPE_DATA; 526 int rc; 527 528 lock_sock(sk); 529 530 if (unlikely(msg->msg_controllen)) { 531 rc = tls_proccess_cmsg(sk, msg, &record_type); 532 if (rc) 533 goto out; 534 } 535 536 rc = tls_push_data(sk, &msg->msg_iter, size, 537 msg->msg_flags, record_type); 538 539 out: 540 release_sock(sk); 541 return rc; 542 } 543 544 int tls_device_sendpage(struct sock *sk, struct page *page, 545 int offset, size_t size, int flags) 546 { 547 struct iov_iter msg_iter; 548 char *kaddr = kmap(page); 549 struct kvec iov; 550 int rc; 551 552 if (flags & MSG_SENDPAGE_NOTLAST) 553 flags |= MSG_MORE; 554 555 lock_sock(sk); 556 557 if (flags & MSG_OOB) { 558 rc = -ENOTSUPP; 559 goto out; 560 } 561 562 iov.iov_base = kaddr + offset; 563 iov.iov_len = size; 564 iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size); 565 rc = tls_push_data(sk, &msg_iter, size, 566 flags, TLS_RECORD_TYPE_DATA); 567 kunmap(page); 568 569 out: 570 release_sock(sk); 571 return rc; 572 } 573 574 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 575 u32 seq, u64 *p_record_sn) 576 { 577 u64 record_sn = context->hint_record_sn; 578 struct tls_record_info *info; 579 580 info = context->retransmit_hint; 581 if (!info || 582 before(seq, info->end_seq - info->len)) { 583 /* if retransmit_hint is irrelevant start 584 * from the beggining of the list 585 */ 586 info = list_first_entry_or_null(&context->records_list, 587 struct tls_record_info, list); 588 if (!info) 589 return NULL; 590 record_sn = context->unacked_record_sn; 591 } 592 593 /* We just need the _rcu for the READ_ONCE() */ 594 rcu_read_lock(); 595 list_for_each_entry_from_rcu(info, &context->records_list, list) { 596 if (before(seq, info->end_seq)) { 597 if (!context->retransmit_hint || 598 after(info->end_seq, 599 context->retransmit_hint->end_seq)) { 600 context->hint_record_sn = record_sn; 601 context->retransmit_hint = info; 602 } 603 *p_record_sn = record_sn; 604 goto exit_rcu_unlock; 605 } 606 record_sn++; 607 } 608 info = NULL; 609 610 exit_rcu_unlock: 611 rcu_read_unlock(); 612 return info; 613 } 614 EXPORT_SYMBOL(tls_get_record); 615 616 static int tls_device_push_pending_record(struct sock *sk, int flags) 617 { 618 struct iov_iter msg_iter; 619 620 iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0); 621 return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA); 622 } 623 624 void tls_device_write_space(struct sock *sk, struct tls_context *ctx) 625 { 626 if (!sk->sk_write_pending && tls_is_partially_sent_record(ctx)) { 627 gfp_t sk_allocation = sk->sk_allocation; 628 629 sk->sk_allocation = GFP_ATOMIC; 630 tls_push_partial_record(sk, ctx, 631 MSG_DONTWAIT | MSG_NOSIGNAL | 632 MSG_SENDPAGE_DECRYPTED); 633 sk->sk_allocation = sk_allocation; 634 } 635 } 636 637 static void tls_device_resync_rx(struct tls_context *tls_ctx, 638 struct sock *sk, u32 seq, u8 *rcd_sn) 639 { 640 struct net_device *netdev; 641 642 if (WARN_ON(test_and_set_bit(TLS_RX_SYNC_RUNNING, &tls_ctx->flags))) 643 return; 644 netdev = READ_ONCE(tls_ctx->netdev); 645 if (netdev) 646 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn, 647 TLS_OFFLOAD_CTX_DIR_RX); 648 clear_bit_unlock(TLS_RX_SYNC_RUNNING, &tls_ctx->flags); 649 } 650 651 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq) 652 { 653 struct tls_context *tls_ctx = tls_get_ctx(sk); 654 struct tls_offload_context_rx *rx_ctx; 655 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; 656 struct tls_prot_info *prot; 657 u32 is_req_pending; 658 s64 resync_req; 659 u32 req_seq; 660 661 if (tls_ctx->rx_conf != TLS_HW) 662 return; 663 664 prot = &tls_ctx->prot_info; 665 rx_ctx = tls_offload_ctx_rx(tls_ctx); 666 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); 667 668 switch (rx_ctx->resync_type) { 669 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ: 670 resync_req = atomic64_read(&rx_ctx->resync_req); 671 req_seq = resync_req >> 32; 672 seq += TLS_HEADER_SIZE - 1; 673 is_req_pending = resync_req; 674 675 if (likely(!is_req_pending) || req_seq != seq || 676 !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0)) 677 return; 678 break; 679 case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT: 680 if (likely(!rx_ctx->resync_nh_do_now)) 681 return; 682 683 /* head of next rec is already in, note that the sock_inq will 684 * include the currently parsed message when called from parser 685 */ 686 if (tcp_inq(sk) > rcd_len) 687 return; 688 689 rx_ctx->resync_nh_do_now = 0; 690 seq += rcd_len; 691 tls_bigint_increment(rcd_sn, prot->rec_seq_size); 692 break; 693 } 694 695 tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn); 696 } 697 698 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx, 699 struct tls_offload_context_rx *ctx, 700 struct sock *sk, struct sk_buff *skb) 701 { 702 struct strp_msg *rxm; 703 704 /* device will request resyncs by itself based on stream scan */ 705 if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT) 706 return; 707 /* already scheduled */ 708 if (ctx->resync_nh_do_now) 709 return; 710 /* seen decrypted fragments since last fully-failed record */ 711 if (ctx->resync_nh_reset) { 712 ctx->resync_nh_reset = 0; 713 ctx->resync_nh.decrypted_failed = 1; 714 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL; 715 return; 716 } 717 718 if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt) 719 return; 720 721 /* doing resync, bump the next target in case it fails */ 722 if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL) 723 ctx->resync_nh.decrypted_tgt *= 2; 724 else 725 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL; 726 727 rxm = strp_msg(skb); 728 729 /* head of next rec is already in, parser will sync for us */ 730 if (tcp_inq(sk) > rxm->full_len) { 731 ctx->resync_nh_do_now = 1; 732 } else { 733 struct tls_prot_info *prot = &tls_ctx->prot_info; 734 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; 735 736 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); 737 tls_bigint_increment(rcd_sn, prot->rec_seq_size); 738 739 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq, 740 rcd_sn); 741 } 742 } 743 744 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb) 745 { 746 struct strp_msg *rxm = strp_msg(skb); 747 int err = 0, offset = rxm->offset, copy, nsg, data_len, pos; 748 struct sk_buff *skb_iter, *unused; 749 struct scatterlist sg[1]; 750 char *orig_buf, *buf; 751 752 orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + 753 TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation); 754 if (!orig_buf) 755 return -ENOMEM; 756 buf = orig_buf; 757 758 nsg = skb_cow_data(skb, 0, &unused); 759 if (unlikely(nsg < 0)) { 760 err = nsg; 761 goto free_buf; 762 } 763 764 sg_init_table(sg, 1); 765 sg_set_buf(&sg[0], buf, 766 rxm->full_len + TLS_HEADER_SIZE + 767 TLS_CIPHER_AES_GCM_128_IV_SIZE); 768 err = skb_copy_bits(skb, offset, buf, 769 TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE); 770 if (err) 771 goto free_buf; 772 773 /* We are interested only in the decrypted data not the auth */ 774 err = decrypt_skb(sk, skb, sg); 775 if (err != -EBADMSG) 776 goto free_buf; 777 else 778 err = 0; 779 780 data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE; 781 782 if (skb_pagelen(skb) > offset) { 783 copy = min_t(int, skb_pagelen(skb) - offset, data_len); 784 785 if (skb->decrypted) { 786 err = skb_store_bits(skb, offset, buf, copy); 787 if (err) 788 goto free_buf; 789 } 790 791 offset += copy; 792 buf += copy; 793 } 794 795 pos = skb_pagelen(skb); 796 skb_walk_frags(skb, skb_iter) { 797 int frag_pos; 798 799 /* Practically all frags must belong to msg if reencrypt 800 * is needed with current strparser and coalescing logic, 801 * but strparser may "get optimized", so let's be safe. 802 */ 803 if (pos + skb_iter->len <= offset) 804 goto done_with_frag; 805 if (pos >= data_len + rxm->offset) 806 break; 807 808 frag_pos = offset - pos; 809 copy = min_t(int, skb_iter->len - frag_pos, 810 data_len + rxm->offset - offset); 811 812 if (skb_iter->decrypted) { 813 err = skb_store_bits(skb_iter, frag_pos, buf, copy); 814 if (err) 815 goto free_buf; 816 } 817 818 offset += copy; 819 buf += copy; 820 done_with_frag: 821 pos += skb_iter->len; 822 } 823 824 free_buf: 825 kfree(orig_buf); 826 return err; 827 } 828 829 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb) 830 { 831 struct tls_context *tls_ctx = tls_get_ctx(sk); 832 struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx); 833 int is_decrypted = skb->decrypted; 834 int is_encrypted = !is_decrypted; 835 struct sk_buff *skb_iter; 836 837 /* Check if all the data is decrypted already */ 838 skb_walk_frags(skb, skb_iter) { 839 is_decrypted &= skb_iter->decrypted; 840 is_encrypted &= !skb_iter->decrypted; 841 } 842 843 ctx->sw.decrypted |= is_decrypted; 844 845 /* Return immediately if the record is either entirely plaintext or 846 * entirely ciphertext. Otherwise handle reencrypt partially decrypted 847 * record. 848 */ 849 if (is_decrypted) { 850 ctx->resync_nh_reset = 1; 851 return 0; 852 } 853 if (is_encrypted) { 854 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb); 855 return 0; 856 } 857 858 ctx->resync_nh_reset = 1; 859 return tls_device_reencrypt(sk, skb); 860 } 861 862 static void tls_device_attach(struct tls_context *ctx, struct sock *sk, 863 struct net_device *netdev) 864 { 865 if (sk->sk_destruct != tls_device_sk_destruct) { 866 refcount_set(&ctx->refcount, 1); 867 dev_hold(netdev); 868 ctx->netdev = netdev; 869 spin_lock_irq(&tls_device_lock); 870 list_add_tail(&ctx->list, &tls_device_list); 871 spin_unlock_irq(&tls_device_lock); 872 873 ctx->sk_destruct = sk->sk_destruct; 874 sk->sk_destruct = tls_device_sk_destruct; 875 } 876 } 877 878 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx) 879 { 880 u16 nonce_size, tag_size, iv_size, rec_seq_size; 881 struct tls_context *tls_ctx = tls_get_ctx(sk); 882 struct tls_prot_info *prot = &tls_ctx->prot_info; 883 struct tls_record_info *start_marker_record; 884 struct tls_offload_context_tx *offload_ctx; 885 struct tls_crypto_info *crypto_info; 886 struct net_device *netdev; 887 char *iv, *rec_seq; 888 struct sk_buff *skb; 889 __be64 rcd_sn; 890 int rc; 891 892 if (!ctx) 893 return -EINVAL; 894 895 if (ctx->priv_ctx_tx) 896 return -EEXIST; 897 898 start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL); 899 if (!start_marker_record) 900 return -ENOMEM; 901 902 offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL); 903 if (!offload_ctx) { 904 rc = -ENOMEM; 905 goto free_marker_record; 906 } 907 908 crypto_info = &ctx->crypto_send.info; 909 if (crypto_info->version != TLS_1_2_VERSION) { 910 rc = -EOPNOTSUPP; 911 goto free_offload_ctx; 912 } 913 914 switch (crypto_info->cipher_type) { 915 case TLS_CIPHER_AES_GCM_128: 916 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE; 917 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE; 918 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE; 919 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv; 920 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE; 921 rec_seq = 922 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq; 923 break; 924 default: 925 rc = -EINVAL; 926 goto free_offload_ctx; 927 } 928 929 /* Sanity-check the rec_seq_size for stack allocations */ 930 if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) { 931 rc = -EINVAL; 932 goto free_offload_ctx; 933 } 934 935 prot->version = crypto_info->version; 936 prot->cipher_type = crypto_info->cipher_type; 937 prot->prepend_size = TLS_HEADER_SIZE + nonce_size; 938 prot->tag_size = tag_size; 939 prot->overhead_size = prot->prepend_size + prot->tag_size; 940 prot->iv_size = iv_size; 941 ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 942 GFP_KERNEL); 943 if (!ctx->tx.iv) { 944 rc = -ENOMEM; 945 goto free_offload_ctx; 946 } 947 948 memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size); 949 950 prot->rec_seq_size = rec_seq_size; 951 ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL); 952 if (!ctx->tx.rec_seq) { 953 rc = -ENOMEM; 954 goto free_iv; 955 } 956 957 rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info); 958 if (rc) 959 goto free_rec_seq; 960 961 /* start at rec_seq - 1 to account for the start marker record */ 962 memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn)); 963 offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1; 964 965 start_marker_record->end_seq = tcp_sk(sk)->write_seq; 966 start_marker_record->len = 0; 967 start_marker_record->num_frags = 0; 968 969 INIT_LIST_HEAD(&offload_ctx->records_list); 970 list_add_tail(&start_marker_record->list, &offload_ctx->records_list); 971 spin_lock_init(&offload_ctx->lock); 972 sg_init_table(offload_ctx->sg_tx_data, 973 ARRAY_SIZE(offload_ctx->sg_tx_data)); 974 975 clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked); 976 ctx->push_pending_record = tls_device_push_pending_record; 977 978 /* TLS offload is greatly simplified if we don't send 979 * SKBs where only part of the payload needs to be encrypted. 980 * So mark the last skb in the write queue as end of record. 981 */ 982 skb = tcp_write_queue_tail(sk); 983 if (skb) 984 TCP_SKB_CB(skb)->eor = 1; 985 986 netdev = get_netdev_for_sock(sk); 987 if (!netdev) { 988 pr_err_ratelimited("%s: netdev not found\n", __func__); 989 rc = -EINVAL; 990 goto disable_cad; 991 } 992 993 if (!(netdev->features & NETIF_F_HW_TLS_TX)) { 994 rc = -ENOTSUPP; 995 goto release_netdev; 996 } 997 998 /* Avoid offloading if the device is down 999 * We don't want to offload new flows after 1000 * the NETDEV_DOWN event 1001 * 1002 * device_offload_lock is taken in tls_devices's NETDEV_DOWN 1003 * handler thus protecting from the device going down before 1004 * ctx was added to tls_device_list. 1005 */ 1006 down_read(&device_offload_lock); 1007 if (!(netdev->flags & IFF_UP)) { 1008 rc = -EINVAL; 1009 goto release_lock; 1010 } 1011 1012 ctx->priv_ctx_tx = offload_ctx; 1013 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX, 1014 &ctx->crypto_send.info, 1015 tcp_sk(sk)->write_seq); 1016 if (rc) 1017 goto release_lock; 1018 1019 tls_device_attach(ctx, sk, netdev); 1020 up_read(&device_offload_lock); 1021 1022 /* following this assignment tls_is_sk_tx_device_offloaded 1023 * will return true and the context might be accessed 1024 * by the netdev's xmit function. 1025 */ 1026 smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb); 1027 dev_put(netdev); 1028 1029 return 0; 1030 1031 release_lock: 1032 up_read(&device_offload_lock); 1033 release_netdev: 1034 dev_put(netdev); 1035 disable_cad: 1036 clean_acked_data_disable(inet_csk(sk)); 1037 crypto_free_aead(offload_ctx->aead_send); 1038 free_rec_seq: 1039 kfree(ctx->tx.rec_seq); 1040 free_iv: 1041 kfree(ctx->tx.iv); 1042 free_offload_ctx: 1043 kfree(offload_ctx); 1044 ctx->priv_ctx_tx = NULL; 1045 free_marker_record: 1046 kfree(start_marker_record); 1047 return rc; 1048 } 1049 1050 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx) 1051 { 1052 struct tls_offload_context_rx *context; 1053 struct net_device *netdev; 1054 int rc = 0; 1055 1056 if (ctx->crypto_recv.info.version != TLS_1_2_VERSION) 1057 return -EOPNOTSUPP; 1058 1059 netdev = get_netdev_for_sock(sk); 1060 if (!netdev) { 1061 pr_err_ratelimited("%s: netdev not found\n", __func__); 1062 return -EINVAL; 1063 } 1064 1065 if (!(netdev->features & NETIF_F_HW_TLS_RX)) { 1066 rc = -ENOTSUPP; 1067 goto release_netdev; 1068 } 1069 1070 /* Avoid offloading if the device is down 1071 * We don't want to offload new flows after 1072 * the NETDEV_DOWN event 1073 * 1074 * device_offload_lock is taken in tls_devices's NETDEV_DOWN 1075 * handler thus protecting from the device going down before 1076 * ctx was added to tls_device_list. 1077 */ 1078 down_read(&device_offload_lock); 1079 if (!(netdev->flags & IFF_UP)) { 1080 rc = -EINVAL; 1081 goto release_lock; 1082 } 1083 1084 context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL); 1085 if (!context) { 1086 rc = -ENOMEM; 1087 goto release_lock; 1088 } 1089 context->resync_nh_reset = 1; 1090 1091 ctx->priv_ctx_rx = context; 1092 rc = tls_set_sw_offload(sk, ctx, 0); 1093 if (rc) 1094 goto release_ctx; 1095 1096 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX, 1097 &ctx->crypto_recv.info, 1098 tcp_sk(sk)->copied_seq); 1099 if (rc) 1100 goto free_sw_resources; 1101 1102 tls_device_attach(ctx, sk, netdev); 1103 up_read(&device_offload_lock); 1104 1105 dev_put(netdev); 1106 1107 return 0; 1108 1109 free_sw_resources: 1110 up_read(&device_offload_lock); 1111 tls_sw_free_resources_rx(sk); 1112 down_read(&device_offload_lock); 1113 release_ctx: 1114 ctx->priv_ctx_rx = NULL; 1115 release_lock: 1116 up_read(&device_offload_lock); 1117 release_netdev: 1118 dev_put(netdev); 1119 return rc; 1120 } 1121 1122 void tls_device_offload_cleanup_rx(struct sock *sk) 1123 { 1124 struct tls_context *tls_ctx = tls_get_ctx(sk); 1125 struct net_device *netdev; 1126 1127 down_read(&device_offload_lock); 1128 netdev = tls_ctx->netdev; 1129 if (!netdev) 1130 goto out; 1131 1132 netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx, 1133 TLS_OFFLOAD_CTX_DIR_RX); 1134 1135 if (tls_ctx->tx_conf != TLS_HW) { 1136 dev_put(netdev); 1137 tls_ctx->netdev = NULL; 1138 } 1139 out: 1140 up_read(&device_offload_lock); 1141 tls_sw_release_resources_rx(sk); 1142 } 1143 1144 static int tls_device_down(struct net_device *netdev) 1145 { 1146 struct tls_context *ctx, *tmp; 1147 unsigned long flags; 1148 LIST_HEAD(list); 1149 1150 /* Request a write lock to block new offload attempts */ 1151 down_write(&device_offload_lock); 1152 1153 spin_lock_irqsave(&tls_device_lock, flags); 1154 list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) { 1155 if (ctx->netdev != netdev || 1156 !refcount_inc_not_zero(&ctx->refcount)) 1157 continue; 1158 1159 list_move(&ctx->list, &list); 1160 } 1161 spin_unlock_irqrestore(&tls_device_lock, flags); 1162 1163 list_for_each_entry_safe(ctx, tmp, &list, list) { 1164 if (ctx->tx_conf == TLS_HW) 1165 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 1166 TLS_OFFLOAD_CTX_DIR_TX); 1167 if (ctx->rx_conf == TLS_HW) 1168 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 1169 TLS_OFFLOAD_CTX_DIR_RX); 1170 WRITE_ONCE(ctx->netdev, NULL); 1171 smp_mb__before_atomic(); /* pairs with test_and_set_bit() */ 1172 while (test_bit(TLS_RX_SYNC_RUNNING, &ctx->flags)) 1173 usleep_range(10, 200); 1174 dev_put(netdev); 1175 list_del_init(&ctx->list); 1176 1177 if (refcount_dec_and_test(&ctx->refcount)) 1178 tls_device_free_ctx(ctx); 1179 } 1180 1181 up_write(&device_offload_lock); 1182 1183 flush_work(&tls_device_gc_work); 1184 1185 return NOTIFY_DONE; 1186 } 1187 1188 static int tls_dev_event(struct notifier_block *this, unsigned long event, 1189 void *ptr) 1190 { 1191 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1192 1193 if (!dev->tlsdev_ops && 1194 !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX))) 1195 return NOTIFY_DONE; 1196 1197 switch (event) { 1198 case NETDEV_REGISTER: 1199 case NETDEV_FEAT_CHANGE: 1200 if ((dev->features & NETIF_F_HW_TLS_RX) && 1201 !dev->tlsdev_ops->tls_dev_resync) 1202 return NOTIFY_BAD; 1203 1204 if (dev->tlsdev_ops && 1205 dev->tlsdev_ops->tls_dev_add && 1206 dev->tlsdev_ops->tls_dev_del) 1207 return NOTIFY_DONE; 1208 else 1209 return NOTIFY_BAD; 1210 case NETDEV_DOWN: 1211 return tls_device_down(dev); 1212 } 1213 return NOTIFY_DONE; 1214 } 1215 1216 static struct notifier_block tls_dev_notifier = { 1217 .notifier_call = tls_dev_event, 1218 }; 1219 1220 void __init tls_device_init(void) 1221 { 1222 register_netdevice_notifier(&tls_dev_notifier); 1223 } 1224 1225 void __exit tls_device_cleanup(void) 1226 { 1227 unregister_netdevice_notifier(&tls_dev_notifier); 1228 flush_work(&tls_device_gc_work); 1229 clean_acked_data_flush(); 1230 } 1231