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