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