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 tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST; 377 int more = flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE); 378 struct tls_record_info *record = ctx->open_record; 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 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); 394 if (tls_is_partially_sent_record(tls_ctx)) { 395 rc = tls_push_partial_record(sk, tls_ctx, flags); 396 if (rc < 0) 397 return rc; 398 } 399 400 pfrag = sk_page_frag(sk); 401 402 /* TLS_HEADER_SIZE is not counted as part of the TLS record, and 403 * we need to leave room for an authentication tag. 404 */ 405 max_open_record_len = TLS_MAX_PAYLOAD_SIZE + 406 prot->prepend_size; 407 do { 408 rc = tls_do_allocation(sk, ctx, pfrag, 409 prot->prepend_size); 410 if (rc) { 411 rc = sk_stream_wait_memory(sk, &timeo); 412 if (!rc) 413 continue; 414 415 record = ctx->open_record; 416 if (!record) 417 break; 418 handle_error: 419 if (record_type != TLS_RECORD_TYPE_DATA) { 420 /* avoid sending partial 421 * record with type != 422 * application_data 423 */ 424 size = orig_size; 425 destroy_record(record); 426 ctx->open_record = NULL; 427 } else if (record->len > prot->prepend_size) { 428 goto last_record; 429 } 430 431 break; 432 } 433 434 record = ctx->open_record; 435 copy = min_t(size_t, size, (pfrag->size - pfrag->offset)); 436 copy = min_t(size_t, copy, (max_open_record_len - record->len)); 437 438 if (copy_from_iter_nocache(page_address(pfrag->page) + 439 pfrag->offset, 440 copy, msg_iter) != copy) { 441 rc = -EFAULT; 442 goto handle_error; 443 } 444 tls_append_frag(record, pfrag, copy); 445 446 size -= copy; 447 if (!size) { 448 last_record: 449 tls_push_record_flags = flags; 450 if (more) { 451 tls_ctx->pending_open_record_frags = 452 !!record->num_frags; 453 break; 454 } 455 456 done = true; 457 } 458 459 if (done || record->len >= max_open_record_len || 460 (record->num_frags >= MAX_SKB_FRAGS - 1)) { 461 rc = tls_push_record(sk, 462 tls_ctx, 463 ctx, 464 record, 465 pfrag, 466 tls_push_record_flags, 467 record_type); 468 if (rc < 0) 469 break; 470 } 471 } while (!done); 472 473 if (orig_size - size > 0) 474 rc = orig_size - size; 475 476 return rc; 477 } 478 479 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) 480 { 481 unsigned char record_type = TLS_RECORD_TYPE_DATA; 482 int rc; 483 484 lock_sock(sk); 485 486 if (unlikely(msg->msg_controllen)) { 487 rc = tls_proccess_cmsg(sk, msg, &record_type); 488 if (rc) 489 goto out; 490 } 491 492 rc = tls_push_data(sk, &msg->msg_iter, size, 493 msg->msg_flags, record_type); 494 495 out: 496 release_sock(sk); 497 return rc; 498 } 499 500 int tls_device_sendpage(struct sock *sk, struct page *page, 501 int offset, size_t size, int flags) 502 { 503 struct iov_iter msg_iter; 504 char *kaddr = kmap(page); 505 struct kvec iov; 506 int rc; 507 508 if (flags & MSG_SENDPAGE_NOTLAST) 509 flags |= MSG_MORE; 510 511 lock_sock(sk); 512 513 if (flags & MSG_OOB) { 514 rc = -ENOTSUPP; 515 goto out; 516 } 517 518 iov.iov_base = kaddr + offset; 519 iov.iov_len = size; 520 iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size); 521 rc = tls_push_data(sk, &msg_iter, size, 522 flags, TLS_RECORD_TYPE_DATA); 523 kunmap(page); 524 525 out: 526 release_sock(sk); 527 return rc; 528 } 529 530 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, 531 u32 seq, u64 *p_record_sn) 532 { 533 u64 record_sn = context->hint_record_sn; 534 struct tls_record_info *info; 535 536 info = context->retransmit_hint; 537 if (!info || 538 before(seq, info->end_seq - info->len)) { 539 /* if retransmit_hint is irrelevant start 540 * from the beggining of the list 541 */ 542 info = list_first_entry(&context->records_list, 543 struct tls_record_info, list); 544 record_sn = context->unacked_record_sn; 545 } 546 547 list_for_each_entry_from(info, &context->records_list, list) { 548 if (before(seq, info->end_seq)) { 549 if (!context->retransmit_hint || 550 after(info->end_seq, 551 context->retransmit_hint->end_seq)) { 552 context->hint_record_sn = record_sn; 553 context->retransmit_hint = info; 554 } 555 *p_record_sn = record_sn; 556 return info; 557 } 558 record_sn++; 559 } 560 561 return NULL; 562 } 563 EXPORT_SYMBOL(tls_get_record); 564 565 static int tls_device_push_pending_record(struct sock *sk, int flags) 566 { 567 struct iov_iter msg_iter; 568 569 iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0); 570 return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA); 571 } 572 573 void tls_device_write_space(struct sock *sk, struct tls_context *ctx) 574 { 575 if (!sk->sk_write_pending && tls_is_partially_sent_record(ctx)) { 576 gfp_t sk_allocation = sk->sk_allocation; 577 578 sk->sk_allocation = GFP_ATOMIC; 579 tls_push_partial_record(sk, ctx, MSG_DONTWAIT | MSG_NOSIGNAL); 580 sk->sk_allocation = sk_allocation; 581 } 582 } 583 584 static void tls_device_resync_rx(struct tls_context *tls_ctx, 585 struct sock *sk, u32 seq, u8 *rcd_sn) 586 { 587 struct net_device *netdev; 588 589 if (WARN_ON(test_and_set_bit(TLS_RX_SYNC_RUNNING, &tls_ctx->flags))) 590 return; 591 netdev = READ_ONCE(tls_ctx->netdev); 592 if (netdev) 593 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn, 594 TLS_OFFLOAD_CTX_DIR_RX); 595 clear_bit_unlock(TLS_RX_SYNC_RUNNING, &tls_ctx->flags); 596 } 597 598 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq) 599 { 600 struct tls_context *tls_ctx = tls_get_ctx(sk); 601 struct tls_offload_context_rx *rx_ctx; 602 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; 603 struct tls_prot_info *prot; 604 u32 is_req_pending; 605 s64 resync_req; 606 u32 req_seq; 607 608 if (tls_ctx->rx_conf != TLS_HW) 609 return; 610 611 prot = &tls_ctx->prot_info; 612 rx_ctx = tls_offload_ctx_rx(tls_ctx); 613 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); 614 615 switch (rx_ctx->resync_type) { 616 case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ: 617 resync_req = atomic64_read(&rx_ctx->resync_req); 618 req_seq = resync_req >> 32; 619 seq += TLS_HEADER_SIZE - 1; 620 is_req_pending = resync_req; 621 622 if (likely(!is_req_pending) || req_seq != seq || 623 !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0)) 624 return; 625 break; 626 case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT: 627 if (likely(!rx_ctx->resync_nh_do_now)) 628 return; 629 630 /* head of next rec is already in, note that the sock_inq will 631 * include the currently parsed message when called from parser 632 */ 633 if (tcp_inq(sk) > rcd_len) 634 return; 635 636 rx_ctx->resync_nh_do_now = 0; 637 seq += rcd_len; 638 tls_bigint_increment(rcd_sn, prot->rec_seq_size); 639 break; 640 } 641 642 tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn); 643 } 644 645 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx, 646 struct tls_offload_context_rx *ctx, 647 struct sock *sk, struct sk_buff *skb) 648 { 649 struct strp_msg *rxm; 650 651 /* device will request resyncs by itself based on stream scan */ 652 if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT) 653 return; 654 /* already scheduled */ 655 if (ctx->resync_nh_do_now) 656 return; 657 /* seen decrypted fragments since last fully-failed record */ 658 if (ctx->resync_nh_reset) { 659 ctx->resync_nh_reset = 0; 660 ctx->resync_nh.decrypted_failed = 1; 661 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL; 662 return; 663 } 664 665 if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt) 666 return; 667 668 /* doing resync, bump the next target in case it fails */ 669 if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL) 670 ctx->resync_nh.decrypted_tgt *= 2; 671 else 672 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL; 673 674 rxm = strp_msg(skb); 675 676 /* head of next rec is already in, parser will sync for us */ 677 if (tcp_inq(sk) > rxm->full_len) { 678 ctx->resync_nh_do_now = 1; 679 } else { 680 struct tls_prot_info *prot = &tls_ctx->prot_info; 681 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; 682 683 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); 684 tls_bigint_increment(rcd_sn, prot->rec_seq_size); 685 686 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq, 687 rcd_sn); 688 } 689 } 690 691 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb) 692 { 693 struct strp_msg *rxm = strp_msg(skb); 694 int err = 0, offset = rxm->offset, copy, nsg, data_len, pos; 695 struct sk_buff *skb_iter, *unused; 696 struct scatterlist sg[1]; 697 char *orig_buf, *buf; 698 699 orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + 700 TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation); 701 if (!orig_buf) 702 return -ENOMEM; 703 buf = orig_buf; 704 705 nsg = skb_cow_data(skb, 0, &unused); 706 if (unlikely(nsg < 0)) { 707 err = nsg; 708 goto free_buf; 709 } 710 711 sg_init_table(sg, 1); 712 sg_set_buf(&sg[0], buf, 713 rxm->full_len + TLS_HEADER_SIZE + 714 TLS_CIPHER_AES_GCM_128_IV_SIZE); 715 err = skb_copy_bits(skb, offset, buf, 716 TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE); 717 if (err) 718 goto free_buf; 719 720 /* We are interested only in the decrypted data not the auth */ 721 err = decrypt_skb(sk, skb, sg); 722 if (err != -EBADMSG) 723 goto free_buf; 724 else 725 err = 0; 726 727 data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE; 728 729 if (skb_pagelen(skb) > offset) { 730 copy = min_t(int, skb_pagelen(skb) - offset, data_len); 731 732 if (skb->decrypted) { 733 err = skb_store_bits(skb, offset, buf, copy); 734 if (err) 735 goto free_buf; 736 } 737 738 offset += copy; 739 buf += copy; 740 } 741 742 pos = skb_pagelen(skb); 743 skb_walk_frags(skb, skb_iter) { 744 int frag_pos; 745 746 /* Practically all frags must belong to msg if reencrypt 747 * is needed with current strparser and coalescing logic, 748 * but strparser may "get optimized", so let's be safe. 749 */ 750 if (pos + skb_iter->len <= offset) 751 goto done_with_frag; 752 if (pos >= data_len + rxm->offset) 753 break; 754 755 frag_pos = offset - pos; 756 copy = min_t(int, skb_iter->len - frag_pos, 757 data_len + rxm->offset - offset); 758 759 if (skb_iter->decrypted) { 760 err = skb_store_bits(skb_iter, frag_pos, buf, copy); 761 if (err) 762 goto free_buf; 763 } 764 765 offset += copy; 766 buf += copy; 767 done_with_frag: 768 pos += skb_iter->len; 769 } 770 771 free_buf: 772 kfree(orig_buf); 773 return err; 774 } 775 776 int tls_device_decrypted(struct sock *sk, struct sk_buff *skb) 777 { 778 struct tls_context *tls_ctx = tls_get_ctx(sk); 779 struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx); 780 int is_decrypted = skb->decrypted; 781 int is_encrypted = !is_decrypted; 782 struct sk_buff *skb_iter; 783 784 /* Check if all the data is decrypted already */ 785 skb_walk_frags(skb, skb_iter) { 786 is_decrypted &= skb_iter->decrypted; 787 is_encrypted &= !skb_iter->decrypted; 788 } 789 790 ctx->sw.decrypted |= is_decrypted; 791 792 /* Return immediately if the record is either entirely plaintext or 793 * entirely ciphertext. Otherwise handle reencrypt partially decrypted 794 * record. 795 */ 796 if (is_decrypted) { 797 ctx->resync_nh_reset = 1; 798 return 0; 799 } 800 if (is_encrypted) { 801 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb); 802 return 0; 803 } 804 805 ctx->resync_nh_reset = 1; 806 return tls_device_reencrypt(sk, skb); 807 } 808 809 static void tls_device_attach(struct tls_context *ctx, struct sock *sk, 810 struct net_device *netdev) 811 { 812 if (sk->sk_destruct != tls_device_sk_destruct) { 813 refcount_set(&ctx->refcount, 1); 814 dev_hold(netdev); 815 ctx->netdev = netdev; 816 spin_lock_irq(&tls_device_lock); 817 list_add_tail(&ctx->list, &tls_device_list); 818 spin_unlock_irq(&tls_device_lock); 819 820 ctx->sk_destruct = sk->sk_destruct; 821 sk->sk_destruct = tls_device_sk_destruct; 822 } 823 } 824 825 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx) 826 { 827 u16 nonce_size, tag_size, iv_size, rec_seq_size; 828 struct tls_context *tls_ctx = tls_get_ctx(sk); 829 struct tls_prot_info *prot = &tls_ctx->prot_info; 830 struct tls_record_info *start_marker_record; 831 struct tls_offload_context_tx *offload_ctx; 832 struct tls_crypto_info *crypto_info; 833 struct net_device *netdev; 834 char *iv, *rec_seq; 835 struct sk_buff *skb; 836 int rc = -EINVAL; 837 __be64 rcd_sn; 838 839 if (!ctx) 840 goto out; 841 842 if (ctx->priv_ctx_tx) { 843 rc = -EEXIST; 844 goto out; 845 } 846 847 start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL); 848 if (!start_marker_record) { 849 rc = -ENOMEM; 850 goto out; 851 } 852 853 offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL); 854 if (!offload_ctx) { 855 rc = -ENOMEM; 856 goto free_marker_record; 857 } 858 859 crypto_info = &ctx->crypto_send.info; 860 if (crypto_info->version != TLS_1_2_VERSION) { 861 rc = -EOPNOTSUPP; 862 goto free_offload_ctx; 863 } 864 865 switch (crypto_info->cipher_type) { 866 case TLS_CIPHER_AES_GCM_128: 867 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE; 868 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE; 869 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE; 870 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv; 871 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE; 872 rec_seq = 873 ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq; 874 break; 875 default: 876 rc = -EINVAL; 877 goto free_offload_ctx; 878 } 879 880 /* Sanity-check the rec_seq_size for stack allocations */ 881 if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) { 882 rc = -EINVAL; 883 goto free_offload_ctx; 884 } 885 886 prot->prepend_size = TLS_HEADER_SIZE + nonce_size; 887 prot->tag_size = tag_size; 888 prot->overhead_size = prot->prepend_size + prot->tag_size; 889 prot->iv_size = iv_size; 890 ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE, 891 GFP_KERNEL); 892 if (!ctx->tx.iv) { 893 rc = -ENOMEM; 894 goto free_offload_ctx; 895 } 896 897 memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size); 898 899 prot->rec_seq_size = rec_seq_size; 900 ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL); 901 if (!ctx->tx.rec_seq) { 902 rc = -ENOMEM; 903 goto free_iv; 904 } 905 906 rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info); 907 if (rc) 908 goto free_rec_seq; 909 910 /* start at rec_seq - 1 to account for the start marker record */ 911 memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn)); 912 offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1; 913 914 start_marker_record->end_seq = tcp_sk(sk)->write_seq; 915 start_marker_record->len = 0; 916 start_marker_record->num_frags = 0; 917 918 INIT_LIST_HEAD(&offload_ctx->records_list); 919 list_add_tail(&start_marker_record->list, &offload_ctx->records_list); 920 spin_lock_init(&offload_ctx->lock); 921 sg_init_table(offload_ctx->sg_tx_data, 922 ARRAY_SIZE(offload_ctx->sg_tx_data)); 923 924 clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked); 925 ctx->push_pending_record = tls_device_push_pending_record; 926 927 /* TLS offload is greatly simplified if we don't send 928 * SKBs where only part of the payload needs to be encrypted. 929 * So mark the last skb in the write queue as end of record. 930 */ 931 skb = tcp_write_queue_tail(sk); 932 if (skb) 933 TCP_SKB_CB(skb)->eor = 1; 934 935 /* We support starting offload on multiple sockets 936 * concurrently, so we only need a read lock here. 937 * This lock must precede get_netdev_for_sock to prevent races between 938 * NETDEV_DOWN and setsockopt. 939 */ 940 down_read(&device_offload_lock); 941 netdev = get_netdev_for_sock(sk); 942 if (!netdev) { 943 pr_err_ratelimited("%s: netdev not found\n", __func__); 944 rc = -EINVAL; 945 goto release_lock; 946 } 947 948 if (!(netdev->features & NETIF_F_HW_TLS_TX)) { 949 rc = -ENOTSUPP; 950 goto release_netdev; 951 } 952 953 /* Avoid offloading if the device is down 954 * We don't want to offload new flows after 955 * the NETDEV_DOWN event 956 */ 957 if (!(netdev->flags & IFF_UP)) { 958 rc = -EINVAL; 959 goto release_netdev; 960 } 961 962 ctx->priv_ctx_tx = offload_ctx; 963 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX, 964 &ctx->crypto_send.info, 965 tcp_sk(sk)->write_seq); 966 if (rc) 967 goto release_netdev; 968 969 tls_device_attach(ctx, sk, netdev); 970 971 /* following this assignment tls_is_sk_tx_device_offloaded 972 * will return true and the context might be accessed 973 * by the netdev's xmit function. 974 */ 975 smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb); 976 dev_put(netdev); 977 up_read(&device_offload_lock); 978 goto out; 979 980 release_netdev: 981 dev_put(netdev); 982 release_lock: 983 up_read(&device_offload_lock); 984 clean_acked_data_disable(inet_csk(sk)); 985 crypto_free_aead(offload_ctx->aead_send); 986 free_rec_seq: 987 kfree(ctx->tx.rec_seq); 988 free_iv: 989 kfree(ctx->tx.iv); 990 free_offload_ctx: 991 kfree(offload_ctx); 992 ctx->priv_ctx_tx = NULL; 993 free_marker_record: 994 kfree(start_marker_record); 995 out: 996 return rc; 997 } 998 999 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx) 1000 { 1001 struct tls_offload_context_rx *context; 1002 struct net_device *netdev; 1003 int rc = 0; 1004 1005 if (ctx->crypto_recv.info.version != TLS_1_2_VERSION) 1006 return -EOPNOTSUPP; 1007 1008 /* We support starting offload on multiple sockets 1009 * concurrently, so we only need a read lock here. 1010 * This lock must precede get_netdev_for_sock to prevent races between 1011 * NETDEV_DOWN and setsockopt. 1012 */ 1013 down_read(&device_offload_lock); 1014 netdev = get_netdev_for_sock(sk); 1015 if (!netdev) { 1016 pr_err_ratelimited("%s: netdev not found\n", __func__); 1017 rc = -EINVAL; 1018 goto release_lock; 1019 } 1020 1021 if (!(netdev->features & NETIF_F_HW_TLS_RX)) { 1022 rc = -ENOTSUPP; 1023 goto release_netdev; 1024 } 1025 1026 /* Avoid offloading if the device is down 1027 * We don't want to offload new flows after 1028 * the NETDEV_DOWN event 1029 */ 1030 if (!(netdev->flags & IFF_UP)) { 1031 rc = -EINVAL; 1032 goto release_netdev; 1033 } 1034 1035 context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL); 1036 if (!context) { 1037 rc = -ENOMEM; 1038 goto release_netdev; 1039 } 1040 context->resync_nh_reset = 1; 1041 1042 ctx->priv_ctx_rx = context; 1043 rc = tls_set_sw_offload(sk, ctx, 0); 1044 if (rc) 1045 goto release_ctx; 1046 1047 rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX, 1048 &ctx->crypto_recv.info, 1049 tcp_sk(sk)->copied_seq); 1050 if (rc) 1051 goto free_sw_resources; 1052 1053 tls_device_attach(ctx, sk, netdev); 1054 goto release_netdev; 1055 1056 free_sw_resources: 1057 up_read(&device_offload_lock); 1058 tls_sw_free_resources_rx(sk); 1059 down_read(&device_offload_lock); 1060 release_ctx: 1061 ctx->priv_ctx_rx = NULL; 1062 release_netdev: 1063 dev_put(netdev); 1064 release_lock: 1065 up_read(&device_offload_lock); 1066 return rc; 1067 } 1068 1069 void tls_device_offload_cleanup_rx(struct sock *sk) 1070 { 1071 struct tls_context *tls_ctx = tls_get_ctx(sk); 1072 struct net_device *netdev; 1073 1074 down_read(&device_offload_lock); 1075 netdev = tls_ctx->netdev; 1076 if (!netdev) 1077 goto out; 1078 1079 netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx, 1080 TLS_OFFLOAD_CTX_DIR_RX); 1081 1082 if (tls_ctx->tx_conf != TLS_HW) { 1083 dev_put(netdev); 1084 tls_ctx->netdev = NULL; 1085 } 1086 out: 1087 up_read(&device_offload_lock); 1088 tls_sw_release_resources_rx(sk); 1089 } 1090 1091 static int tls_device_down(struct net_device *netdev) 1092 { 1093 struct tls_context *ctx, *tmp; 1094 unsigned long flags; 1095 LIST_HEAD(list); 1096 1097 /* Request a write lock to block new offload attempts */ 1098 down_write(&device_offload_lock); 1099 1100 spin_lock_irqsave(&tls_device_lock, flags); 1101 list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) { 1102 if (ctx->netdev != netdev || 1103 !refcount_inc_not_zero(&ctx->refcount)) 1104 continue; 1105 1106 list_move(&ctx->list, &list); 1107 } 1108 spin_unlock_irqrestore(&tls_device_lock, flags); 1109 1110 list_for_each_entry_safe(ctx, tmp, &list, list) { 1111 if (ctx->tx_conf == TLS_HW) 1112 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 1113 TLS_OFFLOAD_CTX_DIR_TX); 1114 if (ctx->rx_conf == TLS_HW) 1115 netdev->tlsdev_ops->tls_dev_del(netdev, ctx, 1116 TLS_OFFLOAD_CTX_DIR_RX); 1117 WRITE_ONCE(ctx->netdev, NULL); 1118 smp_mb__before_atomic(); /* pairs with test_and_set_bit() */ 1119 while (test_bit(TLS_RX_SYNC_RUNNING, &ctx->flags)) 1120 usleep_range(10, 200); 1121 dev_put(netdev); 1122 list_del_init(&ctx->list); 1123 1124 if (refcount_dec_and_test(&ctx->refcount)) 1125 tls_device_free_ctx(ctx); 1126 } 1127 1128 up_write(&device_offload_lock); 1129 1130 flush_work(&tls_device_gc_work); 1131 1132 return NOTIFY_DONE; 1133 } 1134 1135 static int tls_dev_event(struct notifier_block *this, unsigned long event, 1136 void *ptr) 1137 { 1138 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 1139 1140 if (!dev->tlsdev_ops && 1141 !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX))) 1142 return NOTIFY_DONE; 1143 1144 switch (event) { 1145 case NETDEV_REGISTER: 1146 case NETDEV_FEAT_CHANGE: 1147 if ((dev->features & NETIF_F_HW_TLS_RX) && 1148 !dev->tlsdev_ops->tls_dev_resync) 1149 return NOTIFY_BAD; 1150 1151 if (dev->tlsdev_ops && 1152 dev->tlsdev_ops->tls_dev_add && 1153 dev->tlsdev_ops->tls_dev_del) 1154 return NOTIFY_DONE; 1155 else 1156 return NOTIFY_BAD; 1157 case NETDEV_DOWN: 1158 return tls_device_down(dev); 1159 } 1160 return NOTIFY_DONE; 1161 } 1162 1163 static struct notifier_block tls_dev_notifier = { 1164 .notifier_call = tls_dev_event, 1165 }; 1166 1167 void __init tls_device_init(void) 1168 { 1169 register_netdevice_notifier(&tls_dev_notifier); 1170 } 1171 1172 void __exit tls_device_cleanup(void) 1173 { 1174 unregister_netdevice_notifier(&tls_dev_notifier); 1175 flush_work(&tls_device_gc_work); 1176 clean_acked_data_flush(); 1177 } 1178