net/tls/tls_device.c

   1 /* Copyright (c) 2018, Mellanox Technologies All rights reserved.
   2  *
   3  * This software is available to you under a choice of one of two
   4  * licenses.  You may choose to be licensed under the terms of the GNU
   5  * General Public License (GPL) Version 2, available from the file
   6  * COPYING in the main directory of this source tree, or the
   7  * OpenIB.org BSD license below:
   8  *
   9  *     Redistribution and use in source and binary forms, with or
  10  *     without modification, are permitted provided that the following
  11  *     conditions are met:
  12  *
  13  *      - Redistributions of source code must retain the above
  14  *        copyright notice, this list of conditions and the following
  15  *        disclaimer.
  16  *
  17  *      - Redistributions in binary form must reproduce the above
  18  *        copyright notice, this list of conditions and the following
  19  *        disclaimer in the documentation and/or other materials
  20  *        provided with the distribution.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  26  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  27  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  28  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  29  * SOFTWARE.
  30  */
  31
  32 #include <crypto/aead.h>
  33 #include <linux/highmem.h>
  34 #include <linux/module.h>
  35 #include <linux/netdevice.h>
  36 #include <net/dst.h>
  37 #include <net/inet_connection_sock.h>
  38 #include <net/tcp.h>
  39 #include <net/tls.h>
  40
  41 #include "trace.h"
  42
  43 /* device_offload_lock is used to synchronize tls_dev_add
  44  * against NETDEV_DOWN notifications.
  45  */
  46 static DECLARE_RWSEM(device_offload_lock);
  47
  48 static void tls_device_gc_task(struct work_struct *work);
  49
  50 static DECLARE_WORK(tls_device_gc_work, tls_device_gc_task);
  51 static LIST_HEAD(tls_device_gc_list);
  52 static LIST_HEAD(tls_device_list);
  53 static DEFINE_SPINLOCK(tls_device_lock);
  54
  55 static void tls_device_free_ctx(struct tls_context *ctx)
  56 {
  57         if (ctx->tx_conf == TLS_HW) {
  58                 kfree(tls_offload_ctx_tx(ctx));
  59                 kfree(ctx->tx.rec_seq);
  60                 kfree(ctx->tx.iv);
  61         }
  62
  63         if (ctx->rx_conf == TLS_HW)
  64                 kfree(tls_offload_ctx_rx(ctx));
  65
  66         tls_ctx_free(NULL, ctx);
  67 }
  68
  69 static void tls_device_gc_task(struct work_struct *work)
  70 {
  71         struct tls_context *ctx, *tmp;
  72         unsigned long flags;
  73         LIST_HEAD(gc_list);
  74
  75         spin_lock_irqsave(&tls_device_lock, flags);
  76         list_splice_init(&tls_device_gc_list, &gc_list);
  77         spin_unlock_irqrestore(&tls_device_lock, flags);
  78
  79         list_for_each_entry_safe(ctx, tmp, &gc_list, list) {
  80                 struct net_device *netdev = ctx->netdev;
  81
  82                 if (netdev && ctx->tx_conf == TLS_HW) {
  83                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
  84                                                         TLS_OFFLOAD_CTX_DIR_TX);
  85                         dev_put(netdev);
  86                         ctx->netdev = NULL;
  87                 }
  88
  89                 list_del(&ctx->list);
  90                 tls_device_free_ctx(ctx);
  91         }
  92 }
  93
  94 static void tls_device_queue_ctx_destruction(struct tls_context *ctx)
  95 {
  96         unsigned long flags;
  97
  98         spin_lock_irqsave(&tls_device_lock, flags);
  99         list_move_tail(&ctx->list, &tls_device_gc_list);
 100
 101         /* schedule_work inside the spinlock
 102          * to make sure tls_device_down waits for that work.
 103          */
 104         schedule_work(&tls_device_gc_work);
 105
 106         spin_unlock_irqrestore(&tls_device_lock, flags);
 107 }
 108
 109 /* We assume that the socket is already connected */
 110 static struct net_device *get_netdev_for_sock(struct sock *sk)
 111 {
 112         struct dst_entry *dst = sk_dst_get(sk);
 113         struct net_device *netdev = NULL;
 114
 115         if (likely(dst)) {
 116                 netdev = dst->dev;
 117                 dev_hold(netdev);
 118         }
 119
 120         dst_release(dst);
 121
 122         return netdev;
 123 }
 124
 125 static void destroy_record(struct tls_record_info *record)
 126 {
 127         int i;
 128
 129         for (i = 0; i < record->num_frags; i++)
 130                 __skb_frag_unref(&record->frags[i]);
 131         kfree(record);
 132 }
 133
 134 static void delete_all_records(struct tls_offload_context_tx *offload_ctx)
 135 {
 136         struct tls_record_info *info, *temp;
 137
 138         list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) {
 139                 list_del(&info->list);
 140                 destroy_record(info);
 141         }
 142
 143         offload_ctx->retransmit_hint = NULL;
 144 }
 145
 146 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq)
 147 {
 148         struct tls_context *tls_ctx = tls_get_ctx(sk);
 149         struct tls_record_info *info, *temp;
 150         struct tls_offload_context_tx *ctx;
 151         u64 deleted_records = 0;
 152         unsigned long flags;
 153
 154         if (!tls_ctx)
 155                 return;
 156
 157         ctx = tls_offload_ctx_tx(tls_ctx);
 158
 159         spin_lock_irqsave(&ctx->lock, flags);
 160         info = ctx->retransmit_hint;
 161         if (info && !before(acked_seq, info->end_seq))
 162                 ctx->retransmit_hint = NULL;
 163
 164         list_for_each_entry_safe(info, temp, &ctx->records_list, list) {
 165                 if (before(acked_seq, info->end_seq))
 166                         break;
 167                 list_del(&info->list);
 168
 169                 destroy_record(info);
 170                 deleted_records++;
 171         }
 172
 173         ctx->unacked_record_sn += deleted_records;
 174         spin_unlock_irqrestore(&ctx->lock, flags);
 175 }
 176
 177 /* At this point, there should be no references on this
 178  * socket and no in-flight SKBs associated with this
 179  * socket, so it is safe to free all the resources.
 180  */
 181 void tls_device_sk_destruct(struct sock *sk)
 182 {
 183         struct tls_context *tls_ctx = tls_get_ctx(sk);
 184         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 185
 186         tls_ctx->sk_destruct(sk);
 187
 188         if (tls_ctx->tx_conf == TLS_HW) {
 189                 if (ctx->open_record)
 190                         destroy_record(ctx->open_record);
 191                 delete_all_records(ctx);
 192                 crypto_free_aead(ctx->aead_send);
 193                 clean_acked_data_disable(inet_csk(sk));
 194         }
 195
 196         if (refcount_dec_and_test(&tls_ctx->refcount))
 197                 tls_device_queue_ctx_destruction(tls_ctx);
 198 }
 199 EXPORT_SYMBOL_GPL(tls_device_sk_destruct);
 200
 201 void tls_device_free_resources_tx(struct sock *sk)
 202 {
 203         struct tls_context *tls_ctx = tls_get_ctx(sk);
 204
 205         tls_free_partial_record(sk, tls_ctx);
 206 }
 207
 208 void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq)
 209 {
 210         struct tls_context *tls_ctx = tls_get_ctx(sk);
 211
 212         trace_tls_device_tx_resync_req(sk, got_seq, exp_seq);
 213         WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags));
 214 }
 215 EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request);
 216
 217 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
 218                                  u32 seq)
 219 {
 220         struct net_device *netdev;
 221         struct sk_buff *skb;
 222         int err = 0;
 223         u8 *rcd_sn;
 224
 225         skb = tcp_write_queue_tail(sk);
 226         if (skb)
 227                 TCP_SKB_CB(skb)->eor = 1;
 228
 229         rcd_sn = tls_ctx->tx.rec_seq;
 230
 231         trace_tls_device_tx_resync_send(sk, seq, rcd_sn);
 232         down_read(&device_offload_lock);
 233         netdev = tls_ctx->netdev;
 234         if (netdev)
 235                 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq,
 236                                                          rcd_sn,
 237                                                          TLS_OFFLOAD_CTX_DIR_TX);
 238         up_read(&device_offload_lock);
 239         if (err)
 240                 return;
 241
 242         clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
 243 }
 244
 245 static void tls_append_frag(struct tls_record_info *record,
 246                             struct page_frag *pfrag,
 247                             int size)
 248 {
 249         skb_frag_t *frag;
 250
 251         frag = &record->frags[record->num_frags - 1];
 252         if (skb_frag_page(frag) == pfrag->page &&
 253             skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
 254                 skb_frag_size_add(frag, size);
 255         } else {
 256                 ++frag;
 257                 __skb_frag_set_page(frag, pfrag->page);
 258                 skb_frag_off_set(frag, pfrag->offset);
 259                 skb_frag_size_set(frag, size);
 260                 ++record->num_frags;
 261                 get_page(pfrag->page);
 262         }
 263
 264         pfrag->offset += size;
 265         record->len += size;
 266 }
 267
 268 static int tls_push_record(struct sock *sk,
 269                            struct tls_context *ctx,
 270                            struct tls_offload_context_tx *offload_ctx,
 271                            struct tls_record_info *record,
 272                            int flags)
 273 {
 274         struct tls_prot_info *prot = &ctx->prot_info;
 275         struct tcp_sock *tp = tcp_sk(sk);
 276         skb_frag_t *frag;
 277         int i;
 278
 279         record->end_seq = tp->write_seq + record->len;
 280         list_add_tail_rcu(&record->list, &offload_ctx->records_list);
 281         offload_ctx->open_record = NULL;
 282
 283         if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
 284                 tls_device_resync_tx(sk, ctx, tp->write_seq);
 285
 286         tls_advance_record_sn(sk, prot, &ctx->tx);
 287
 288         for (i = 0; i < record->num_frags; i++) {
 289                 frag = &record->frags[i];
 290                 sg_unmark_end(&offload_ctx->sg_tx_data[i]);
 291                 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
 292                             skb_frag_size(frag), skb_frag_off(frag));
 293                 sk_mem_charge(sk, skb_frag_size(frag));
 294                 get_page(skb_frag_page(frag));
 295         }
 296         sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
 297
 298         /* all ready, send */
 299         return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
 300 }
 301
 302 static int tls_device_record_close(struct sock *sk,
 303                                    struct tls_context *ctx,
 304                                    struct tls_record_info *record,
 305                                    struct page_frag *pfrag,
 306                                    unsigned char record_type)
 307 {
 308         struct tls_prot_info *prot = &ctx->prot_info;
 309         int ret;
 310
 311         /* append tag
 312          * device will fill in the tag, we just need to append a placeholder
 313          * use socket memory to improve coalescing (re-using a single buffer
 314          * increases frag count)
 315          * if we can't allocate memory now, steal some back from data
 316          */
 317         if (likely(skb_page_frag_refill(prot->tag_size, pfrag,
 318                                         sk->sk_allocation))) {
 319                 ret = 0;
 320                 tls_append_frag(record, pfrag, prot->tag_size);
 321         } else {
 322                 ret = prot->tag_size;
 323                 if (record->len <= prot->overhead_size)
 324                         return -ENOMEM;
 325         }
 326
 327         /* fill prepend */
 328         tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
 329                          record->len - prot->overhead_size,
 330                          record_type, prot->version);
 331         return ret;
 332 }
 333
 334 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
 335                                  struct page_frag *pfrag,
 336                                  size_t prepend_size)
 337 {
 338         struct tls_record_info *record;
 339         skb_frag_t *frag;
 340
 341         record = kmalloc(sizeof(*record), GFP_KERNEL);
 342         if (!record)
 343                 return -ENOMEM;
 344
 345         frag = &record->frags[0];
 346         __skb_frag_set_page(frag, pfrag->page);
 347         skb_frag_off_set(frag, pfrag->offset);
 348         skb_frag_size_set(frag, prepend_size);
 349
 350         get_page(pfrag->page);
 351         pfrag->offset += prepend_size;
 352
 353         record->num_frags = 1;
 354         record->len = prepend_size;
 355         offload_ctx->open_record = record;
 356         return 0;
 357 }
 358
 359 static int tls_do_allocation(struct sock *sk,
 360                              struct tls_offload_context_tx *offload_ctx,
 361                              struct page_frag *pfrag,
 362                              size_t prepend_size)
 363 {
 364         int ret;
 365
 366         if (!offload_ctx->open_record) {
 367                 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
 368                                                    sk->sk_allocation))) {
 369                         READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
 370                         sk_stream_moderate_sndbuf(sk);
 371                         return -ENOMEM;
 372                 }
 373
 374                 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
 375                 if (ret)
 376                         return ret;
 377
 378                 if (pfrag->size > pfrag->offset)
 379                         return 0;
 380         }
 381
 382         if (!sk_page_frag_refill(sk, pfrag))
 383                 return -ENOMEM;
 384
 385         return 0;
 386 }
 387
 388 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
 389 {
 390         size_t pre_copy, nocache;
 391
 392         pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
 393         if (pre_copy) {
 394                 pre_copy = min(pre_copy, bytes);
 395                 if (copy_from_iter(addr, pre_copy, i) != pre_copy)
 396                         return -EFAULT;
 397                 bytes -= pre_copy;
 398                 addr += pre_copy;
 399         }
 400
 401         nocache = round_down(bytes, SMP_CACHE_BYTES);
 402         if (copy_from_iter_nocache(addr, nocache, i) != nocache)
 403                 return -EFAULT;
 404         bytes -= nocache;
 405         addr += nocache;
 406
 407         if (bytes && copy_from_iter(addr, bytes, i) != bytes)
 408                 return -EFAULT;
 409
 410         return 0;
 411 }
 412
 413 static int tls_push_data(struct sock *sk,
 414                          struct iov_iter *msg_iter,
 415                          size_t size, int flags,
 416                          unsigned char record_type)
 417 {
 418         struct tls_context *tls_ctx = tls_get_ctx(sk);
 419         struct tls_prot_info *prot = &tls_ctx->prot_info;
 420         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 421         int more = flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE);
 422         struct tls_record_info *record = ctx->open_record;
 423         int tls_push_record_flags;
 424         struct page_frag *pfrag;
 425         size_t orig_size = size;
 426         u32 max_open_record_len;
 427         int copy, rc = 0;
 428         bool done = false;
 429         long timeo;
 430
 431         if (flags &
 432             ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
 433                 return -EOPNOTSUPP;
 434
 435         if (unlikely(sk->sk_err))
 436                 return -sk->sk_err;
 437
 438         flags |= MSG_SENDPAGE_DECRYPTED;
 439         tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST;
 440
 441         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
 442         if (tls_is_partially_sent_record(tls_ctx)) {
 443                 rc = tls_push_partial_record(sk, tls_ctx, flags);
 444                 if (rc < 0)
 445                         return rc;
 446         }
 447
 448         pfrag = sk_page_frag(sk);
 449
 450         /* TLS_HEADER_SIZE is not counted as part of the TLS record, and
 451          * we need to leave room for an authentication tag.
 452          */
 453         max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
 454                               prot->prepend_size;
 455         do {
 456                 rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
 457                 if (unlikely(rc)) {
 458                         rc = sk_stream_wait_memory(sk, &timeo);
 459                         if (!rc)
 460                                 continue;
 461
 462                         record = ctx->open_record;
 463                         if (!record)
 464                                 break;
 465 handle_error:
 466                         if (record_type != TLS_RECORD_TYPE_DATA) {
 467                                 /* avoid sending partial
 468                                  * record with type !=
 469                                  * application_data
 470                                  */
 471                                 size = orig_size;
 472                                 destroy_record(record);
 473                                 ctx->open_record = NULL;
 474                         } else if (record->len > prot->prepend_size) {
 475                                 goto last_record;
 476                         }
 477
 478                         break;
 479                 }
 480
 481                 record = ctx->open_record;
 482                 copy = min_t(size_t, size, (pfrag->size - pfrag->offset));
 483                 copy = min_t(size_t, copy, (max_open_record_len - record->len));
 484
 485                 rc = tls_device_copy_data(page_address(pfrag->page) +
 486                                           pfrag->offset, copy, msg_iter);
 487                 if (rc)
 488                         goto handle_error;
 489                 tls_append_frag(record, pfrag, copy);
 490
 491                 size -= copy;
 492                 if (!size) {
 493 last_record:
 494                         tls_push_record_flags = flags;
 495                         if (more) {
 496                                 tls_ctx->pending_open_record_frags =
 497                                                 !!record->num_frags;
 498                                 break;
 499                         }
 500
 501                         done = true;
 502                 }
 503
 504                 if (done || record->len >= max_open_record_len ||
 505                     (record->num_frags >= MAX_SKB_FRAGS - 1)) {
 506                         rc = tls_device_record_close(sk, tls_ctx, record,
 507                                                      pfrag, record_type);
 508                         if (rc) {
 509                                 if (rc > 0) {
 510                                         size += rc;
 511                                 } else {
 512                                         size = orig_size;
 513                                         destroy_record(record);
 514                                         ctx->open_record = NULL;
 515                                         break;
 516                                 }
 517                         }
 518
 519                         rc = tls_push_record(sk,
 520                                              tls_ctx,
 521                                              ctx,
 522                                              record,
 523                                              tls_push_record_flags);
 524                         if (rc < 0)
 525                                 break;
 526                 }
 527         } while (!done);
 528
 529         if (orig_size - size > 0)
 530                 rc = orig_size - size;
 531
 532         return rc;
 533 }
 534
 535 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 536 {
 537         unsigned char record_type = TLS_RECORD_TYPE_DATA;
 538         struct tls_context *tls_ctx = tls_get_ctx(sk);
 539         int rc;
 540
 541         mutex_lock(&tls_ctx->tx_lock);
 542         lock_sock(sk);
 543
 544         if (unlikely(msg->msg_controllen)) {
 545                 rc = tls_proccess_cmsg(sk, msg, &record_type);
 546                 if (rc)
 547                         goto out;
 548         }
 549
 550         rc = tls_push_data(sk, &msg->msg_iter, size,
 551                            msg->msg_flags, record_type);
 552
 553 out:
 554         release_sock(sk);
 555         mutex_unlock(&tls_ctx->tx_lock);
 556         return rc;
 557 }
 558
 559 int tls_device_sendpage(struct sock *sk, struct page *page,
 560                         int offset, size_t size, int flags)
 561 {
 562         struct tls_context *tls_ctx = tls_get_ctx(sk);
 563         struct iov_iter msg_iter;
 564         char *kaddr;
 565         struct kvec iov;
 566         int rc;
 567
 568         if (flags & MSG_SENDPAGE_NOTLAST)
 569                 flags |= MSG_MORE;
 570
 571         mutex_lock(&tls_ctx->tx_lock);
 572         lock_sock(sk);
 573
 574         if (flags & MSG_OOB) {
 575                 rc = -EOPNOTSUPP;
 576                 goto out;
 577         }
 578
 579         kaddr = kmap(page);
 580         iov.iov_base = kaddr + offset;
 581         iov.iov_len = size;
 582         iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);
 583         rc = tls_push_data(sk, &msg_iter, size,
 584                            flags, TLS_RECORD_TYPE_DATA);
 585         kunmap(page);
 586
 587 out:
 588         release_sock(sk);
 589         mutex_unlock(&tls_ctx->tx_lock);
 590         return rc;
 591 }
 592
 593 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
 594                                        u32 seq, u64 *p_record_sn)
 595 {
 596         u64 record_sn = context->hint_record_sn;
 597         struct tls_record_info *info, *last;
 598
 599         info = context->retransmit_hint;
 600         if (!info ||
 601             before(seq, info->end_seq - info->len)) {
 602                 /* if retransmit_hint is irrelevant start
 603                  * from the beggining of the list
 604                  */
 605                 info = list_first_entry_or_null(&context->records_list,
 606                                                 struct tls_record_info, list);
 607                 if (!info)
 608                         return NULL;
 609                 /* send the start_marker record if seq number is before the
 610                  * tls offload start marker sequence number. This record is
 611                  * required to handle TCP packets which are before TLS offload
 612                  * started.
 613                  *  And if it's not start marker, look if this seq number
 614                  * belongs to the list.
 615                  */
 616                 if (likely(!tls_record_is_start_marker(info))) {
 617                         /* we have the first record, get the last record to see
 618                          * if this seq number belongs to the list.
 619                          */
 620                         last = list_last_entry(&context->records_list,
 621                                                struct tls_record_info, list);
 622
 623                         if (!between(seq, tls_record_start_seq(info),
 624                                      last->end_seq))
 625                                 return NULL;
 626                 }
 627                 record_sn = context->unacked_record_sn;
 628         }
 629
 630         /* We just need the _rcu for the READ_ONCE() */
 631         rcu_read_lock();
 632         list_for_each_entry_from_rcu(info, &context->records_list, list) {
 633                 if (before(seq, info->end_seq)) {
 634                         if (!context->retransmit_hint ||
 635                             after(info->end_seq,
 636                                   context->retransmit_hint->end_seq)) {
 637                                 context->hint_record_sn = record_sn;
 638                                 context->retransmit_hint = info;
 639                         }
 640                         *p_record_sn = record_sn;
 641                         goto exit_rcu_unlock;
 642                 }
 643                 record_sn++;
 644         }
 645         info = NULL;
 646
 647 exit_rcu_unlock:
 648         rcu_read_unlock();
 649         return info;
 650 }
 651 EXPORT_SYMBOL(tls_get_record);
 652
 653 static int tls_device_push_pending_record(struct sock *sk, int flags)
 654 {
 655         struct iov_iter msg_iter;
 656
 657         iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0);
 658         return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA);
 659 }
 660
 661 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 662 {
 663         if (tls_is_partially_sent_record(ctx)) {
 664                 gfp_t sk_allocation = sk->sk_allocation;
 665
 666                 WARN_ON_ONCE(sk->sk_write_pending);
 667
 668                 sk->sk_allocation = GFP_ATOMIC;
 669                 tls_push_partial_record(sk, ctx,
 670                                         MSG_DONTWAIT | MSG_NOSIGNAL |
 671                                         MSG_SENDPAGE_DECRYPTED);
 672                 sk->sk_allocation = sk_allocation;
 673         }
 674 }
 675
 676 static void tls_device_resync_rx(struct tls_context *tls_ctx,
 677                                  struct sock *sk, u32 seq, u8 *rcd_sn)
 678 {
 679         struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
 680         struct net_device *netdev;
 681
 682         if (WARN_ON(test_and_set_bit(TLS_RX_SYNC_RUNNING, &tls_ctx->flags)))
 683                 return;
 684
 685         trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
 686         netdev = READ_ONCE(tls_ctx->netdev);
 687         if (netdev)
 688                 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
 689                                                    TLS_OFFLOAD_CTX_DIR_RX);
 690         clear_bit_unlock(TLS_RX_SYNC_RUNNING, &tls_ctx->flags);
 691         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
 692 }
 693
 694 static bool
 695 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
 696                            s64 resync_req, u32 *seq)
 697 {
 698         u32 is_async = resync_req & RESYNC_REQ_ASYNC;
 699         u32 req_seq = resync_req >> 32;
 700         u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
 701
 702         if (is_async) {
 703                 /* asynchronous stage: log all headers seq such that
 704                  * req_seq <= seq <= end_seq, and wait for real resync request
 705                  */
 706                 if (between(*seq, req_seq, req_end) &&
 707                     resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
 708                         resync_async->log[resync_async->loglen++] = *seq;
 709
 710                 return false;
 711         }
 712
 713         /* synchronous stage: check against the logged entries and
 714          * proceed to check the next entries if no match was found
 715          */
 716         while (resync_async->loglen) {
 717                 if (req_seq == resync_async->log[resync_async->loglen - 1] &&
 718                     atomic64_try_cmpxchg(&resync_async->req,
 719                                          &resync_req, 0)) {
 720                         resync_async->loglen = 0;
 721                         *seq = req_seq;
 722                         return true;
 723                 }
 724                 resync_async->loglen--;
 725         }
 726
 727         if (req_seq == *seq &&
 728             atomic64_try_cmpxchg(&resync_async->req,
 729                                  &resync_req, 0))
 730                 return true;
 731
 732         return false;
 733 }
 734
 735 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
 736 {
 737         struct tls_context *tls_ctx = tls_get_ctx(sk);
 738         struct tls_offload_context_rx *rx_ctx;
 739         u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 740         u32 sock_data, is_req_pending;
 741         struct tls_prot_info *prot;
 742         s64 resync_req;
 743         u32 req_seq;
 744
 745         if (tls_ctx->rx_conf != TLS_HW)
 746                 return;
 747
 748         prot = &tls_ctx->prot_info;
 749         rx_ctx = tls_offload_ctx_rx(tls_ctx);
 750         memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 751
 752         switch (rx_ctx->resync_type) {
 753         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
 754                 resync_req = atomic64_read(&rx_ctx->resync_req);
 755                 req_seq = resync_req >> 32;
 756                 seq += TLS_HEADER_SIZE - 1;
 757                 is_req_pending = resync_req;
 758
 759                 if (likely(!is_req_pending) || req_seq != seq ||
 760                     !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
 761                         return;
 762                 break;
 763         case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
 764                 if (likely(!rx_ctx->resync_nh_do_now))
 765                         return;
 766
 767                 /* head of next rec is already in, note that the sock_inq will
 768                  * include the currently parsed message when called from parser
 769                  */
 770                 sock_data = tcp_inq(sk);
 771                 if (sock_data > rcd_len) {
 772                         trace_tls_device_rx_resync_nh_delay(sk, sock_data,
 773                                                             rcd_len);
 774                         return;
 775                 }
 776
 777                 rx_ctx->resync_nh_do_now = 0;
 778                 seq += rcd_len;
 779                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 780                 break;
 781         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
 782                 resync_req = atomic64_read(&rx_ctx->resync_async->req);
 783                 is_req_pending = resync_req;
 784                 if (likely(!is_req_pending))
 785                         return;
 786
 787                 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
 788                                                 resync_req, &seq))
 789                         return;
 790                 break;
 791         }
 792
 793         tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
 794 }
 795
 796 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
 797                                            struct tls_offload_context_rx *ctx,
 798                                            struct sock *sk, struct sk_buff *skb)
 799 {
 800         struct strp_msg *rxm;
 801
 802         /* device will request resyncs by itself based on stream scan */
 803         if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
 804                 return;
 805         /* already scheduled */
 806         if (ctx->resync_nh_do_now)
 807                 return;
 808         /* seen decrypted fragments since last fully-failed record */
 809         if (ctx->resync_nh_reset) {
 810                 ctx->resync_nh_reset = 0;
 811                 ctx->resync_nh.decrypted_failed = 1;
 812                 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
 813                 return;
 814         }
 815
 816         if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
 817                 return;
 818
 819         /* doing resync, bump the next target in case it fails */
 820         if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
 821                 ctx->resync_nh.decrypted_tgt *= 2;
 822         else
 823                 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
 824
 825         rxm = strp_msg(skb);
 826
 827         /* head of next rec is already in, parser will sync for us */
 828         if (tcp_inq(sk) > rxm->full_len) {
 829                 trace_tls_device_rx_resync_nh_schedule(sk);
 830                 ctx->resync_nh_do_now = 1;
 831         } else {
 832                 struct tls_prot_info *prot = &tls_ctx->prot_info;
 833                 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 834
 835                 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 836                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 837
 838                 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
 839                                      rcd_sn);
 840         }
 841 }
 842
 843 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
 844 {
 845         struct strp_msg *rxm = strp_msg(skb);
 846         int err = 0, offset = rxm->offset, copy, nsg, data_len, pos;
 847         struct sk_buff *skb_iter, *unused;
 848         struct scatterlist sg[1];
 849         char *orig_buf, *buf;
 850
 851         orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE +
 852                            TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation);
 853         if (!orig_buf)
 854                 return -ENOMEM;
 855         buf = orig_buf;
 856
 857         nsg = skb_cow_data(skb, 0, &unused);
 858         if (unlikely(nsg < 0)) {
 859                 err = nsg;
 860                 goto free_buf;
 861         }
 862
 863         sg_init_table(sg, 1);
 864         sg_set_buf(&sg[0], buf,
 865                    rxm->full_len + TLS_HEADER_SIZE +
 866                    TLS_CIPHER_AES_GCM_128_IV_SIZE);
 867         err = skb_copy_bits(skb, offset, buf,
 868                             TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
 869         if (err)
 870                 goto free_buf;
 871
 872         /* We are interested only in the decrypted data not the auth */
 873         err = decrypt_skb(sk, skb, sg);
 874         if (err != -EBADMSG)
 875                 goto free_buf;
 876         else
 877                 err = 0;
 878
 879         data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE;
 880
 881         if (skb_pagelen(skb) > offset) {
 882                 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 883
 884                 if (skb->decrypted) {
 885                         err = skb_store_bits(skb, offset, buf, copy);
 886                         if (err)
 887                                 goto free_buf;
 888                 }
 889
 890                 offset += copy;
 891                 buf += copy;
 892         }
 893
 894         pos = skb_pagelen(skb);
 895         skb_walk_frags(skb, skb_iter) {
 896                 int frag_pos;
 897
 898                 /* Practically all frags must belong to msg if reencrypt
 899                  * is needed with current strparser and coalescing logic,
 900                  * but strparser may "get optimized", so let's be safe.
 901                  */
 902                 if (pos + skb_iter->len <= offset)
 903                         goto done_with_frag;
 904                 if (pos >= data_len + rxm->offset)
 905                         break;
 906
 907                 frag_pos = offset - pos;
 908                 copy = min_t(int, skb_iter->len - frag_pos,
 909                              data_len + rxm->offset - offset);
 910
 911                 if (skb_iter->decrypted) {
 912                         err = skb_store_bits(skb_iter, frag_pos, buf, copy);
 913                         if (err)
 914                                 goto free_buf;
 915                 }
 916
 917                 offset += copy;
 918                 buf += copy;
 919 done_with_frag:
 920                 pos += skb_iter->len;
 921         }
 922
 923 free_buf:
 924         kfree(orig_buf);
 925         return err;
 926 }
 927
 928 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx,
 929                          struct sk_buff *skb, struct strp_msg *rxm)
 930 {
 931         struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
 932         int is_decrypted = skb->decrypted;
 933         int is_encrypted = !is_decrypted;
 934         struct sk_buff *skb_iter;
 935
 936         /* Check if all the data is decrypted already */
 937         skb_walk_frags(skb, skb_iter) {
 938                 is_decrypted &= skb_iter->decrypted;
 939                 is_encrypted &= !skb_iter->decrypted;
 940         }
 941
 942         trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
 943                                    tls_ctx->rx.rec_seq, rxm->full_len,
 944                                    is_encrypted, is_decrypted);
 945
 946         ctx->sw.decrypted |= is_decrypted;
 947
 948         /* Return immediately if the record is either entirely plaintext or
 949          * entirely ciphertext. Otherwise handle reencrypt partially decrypted
 950          * record.
 951          */
 952         if (is_decrypted) {
 953                 ctx->resync_nh_reset = 1;
 954                 return 0;
 955         }
 956         if (is_encrypted) {
 957                 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
 958                 return 0;
 959         }
 960
 961         ctx->resync_nh_reset = 1;
 962         return tls_device_reencrypt(sk, skb);
 963 }
 964
 965 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
 966                               struct net_device *netdev)
 967 {
 968         if (sk->sk_destruct != tls_device_sk_destruct) {
 969                 refcount_set(&ctx->refcount, 1);
 970                 dev_hold(netdev);
 971                 ctx->netdev = netdev;
 972                 spin_lock_irq(&tls_device_lock);
 973                 list_add_tail(&ctx->list, &tls_device_list);
 974                 spin_unlock_irq(&tls_device_lock);
 975
 976                 ctx->sk_destruct = sk->sk_destruct;
 977                 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
 978         }
 979 }
 980
 981 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
 982 {
 983         u16 nonce_size, tag_size, iv_size, rec_seq_size;
 984         struct tls_context *tls_ctx = tls_get_ctx(sk);
 985         struct tls_prot_info *prot = &tls_ctx->prot_info;
 986         struct tls_record_info *start_marker_record;
 987         struct tls_offload_context_tx *offload_ctx;
 988         struct tls_crypto_info *crypto_info;
 989         struct net_device *netdev;
 990         char *iv, *rec_seq;
 991         struct sk_buff *skb;
 992         __be64 rcd_sn;
 993         int rc;
 994
 995         if (!ctx)
 996                 return -EINVAL;
 997
 998         if (ctx->priv_ctx_tx)
 999                 return -EEXIST;
1000
1001         start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1002         if (!start_marker_record)
1003                 return -ENOMEM;
1004
1005         offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
1006         if (!offload_ctx) {
1007                 rc = -ENOMEM;
1008                 goto free_marker_record;
1009         }
1010
1011         crypto_info = &ctx->crypto_send.info;
1012         if (crypto_info->version != TLS_1_2_VERSION) {
1013                 rc = -EOPNOTSUPP;
1014                 goto free_offload_ctx;
1015         }
1016
1017         switch (crypto_info->cipher_type) {
1018         case TLS_CIPHER_AES_GCM_128:
1019                 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1020                 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
1021                 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1022                 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
1023                 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
1024                 rec_seq =
1025                  ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
1026                 break;
1027         default:
1028                 rc = -EINVAL;
1029                 goto free_offload_ctx;
1030         }
1031
1032         /* Sanity-check the rec_seq_size for stack allocations */
1033         if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
1034                 rc = -EINVAL;
1035                 goto free_offload_ctx;
1036         }
1037
1038         prot->version = crypto_info->version;
1039         prot->cipher_type = crypto_info->cipher_type;
1040         prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
1041         prot->tag_size = tag_size;
1042         prot->overhead_size = prot->prepend_size + prot->tag_size;
1043         prot->iv_size = iv_size;
1044         ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
1045                              GFP_KERNEL);
1046         if (!ctx->tx.iv) {
1047                 rc = -ENOMEM;
1048                 goto free_offload_ctx;
1049         }
1050
1051         memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
1052
1053         prot->rec_seq_size = rec_seq_size;
1054         ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
1055         if (!ctx->tx.rec_seq) {
1056                 rc = -ENOMEM;
1057                 goto free_iv;
1058         }
1059
1060         rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1061         if (rc)
1062                 goto free_rec_seq;
1063
1064         /* start at rec_seq - 1 to account for the start marker record */
1065         memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1066         offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1067
1068         start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1069         start_marker_record->len = 0;
1070         start_marker_record->num_frags = 0;
1071
1072         INIT_LIST_HEAD(&offload_ctx->records_list);
1073         list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1074         spin_lock_init(&offload_ctx->lock);
1075         sg_init_table(offload_ctx->sg_tx_data,
1076                       ARRAY_SIZE(offload_ctx->sg_tx_data));
1077
1078         clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1079         ctx->push_pending_record = tls_device_push_pending_record;
1080
1081         /* TLS offload is greatly simplified if we don't send
1082          * SKBs where only part of the payload needs to be encrypted.
1083          * So mark the last skb in the write queue as end of record.
1084          */
1085         skb = tcp_write_queue_tail(sk);
1086         if (skb)
1087                 TCP_SKB_CB(skb)->eor = 1;
1088
1089         netdev = get_netdev_for_sock(sk);
1090         if (!netdev) {
1091                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1092                 rc = -EINVAL;
1093                 goto disable_cad;
1094         }
1095
1096         if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1097                 rc = -EOPNOTSUPP;
1098                 goto release_netdev;
1099         }
1100
1101         /* Avoid offloading if the device is down
1102          * We don't want to offload new flows after
1103          * the NETDEV_DOWN event
1104          *
1105          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1106          * handler thus protecting from the device going down before
1107          * ctx was added to tls_device_list.
1108          */
1109         down_read(&device_offload_lock);
1110         if (!(netdev->flags & IFF_UP)) {
1111                 rc = -EINVAL;
1112                 goto release_lock;
1113         }
1114
1115         ctx->priv_ctx_tx = offload_ctx;
1116         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1117                                              &ctx->crypto_send.info,
1118                                              tcp_sk(sk)->write_seq);
1119         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1120                                      tcp_sk(sk)->write_seq, rec_seq, rc);
1121         if (rc)
1122                 goto release_lock;
1123
1124         tls_device_attach(ctx, sk, netdev);
1125         up_read(&device_offload_lock);
1126
1127         /* following this assignment tls_is_sk_tx_device_offloaded
1128          * will return true and the context might be accessed
1129          * by the netdev's xmit function.
1130          */
1131         smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1132         dev_put(netdev);
1133
1134         return 0;
1135
1136 release_lock:
1137         up_read(&device_offload_lock);
1138 release_netdev:
1139         dev_put(netdev);
1140 disable_cad:
1141         clean_acked_data_disable(inet_csk(sk));
1142         crypto_free_aead(offload_ctx->aead_send);
1143 free_rec_seq:
1144         kfree(ctx->tx.rec_seq);
1145 free_iv:
1146         kfree(ctx->tx.iv);
1147 free_offload_ctx:
1148         kfree(offload_ctx);
1149         ctx->priv_ctx_tx = NULL;
1150 free_marker_record:
1151         kfree(start_marker_record);
1152         return rc;
1153 }
1154
1155 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1156 {
1157         struct tls12_crypto_info_aes_gcm_128 *info;
1158         struct tls_offload_context_rx *context;
1159         struct net_device *netdev;
1160         int rc = 0;
1161
1162         if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1163                 return -EOPNOTSUPP;
1164
1165         netdev = get_netdev_for_sock(sk);
1166         if (!netdev) {
1167                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1168                 return -EINVAL;
1169         }
1170
1171         if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1172                 rc = -EOPNOTSUPP;
1173                 goto release_netdev;
1174         }
1175
1176         /* Avoid offloading if the device is down
1177          * We don't want to offload new flows after
1178          * the NETDEV_DOWN event
1179          *
1180          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1181          * handler thus protecting from the device going down before
1182          * ctx was added to tls_device_list.
1183          */
1184         down_read(&device_offload_lock);
1185         if (!(netdev->flags & IFF_UP)) {
1186                 rc = -EINVAL;
1187                 goto release_lock;
1188         }
1189
1190         context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1191         if (!context) {
1192                 rc = -ENOMEM;
1193                 goto release_lock;
1194         }
1195         context->resync_nh_reset = 1;
1196
1197         ctx->priv_ctx_rx = context;
1198         rc = tls_set_sw_offload(sk, ctx, 0);
1199         if (rc)
1200                 goto release_ctx;
1201
1202         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1203                                              &ctx->crypto_recv.info,
1204                                              tcp_sk(sk)->copied_seq);
1205         info = (void *)&ctx->crypto_recv.info;
1206         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1207                                      tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1208         if (rc)
1209                 goto free_sw_resources;
1210
1211         tls_device_attach(ctx, sk, netdev);
1212         up_read(&device_offload_lock);
1213
1214         dev_put(netdev);
1215
1216         return 0;
1217
1218 free_sw_resources:
1219         up_read(&device_offload_lock);
1220         tls_sw_free_resources_rx(sk);
1221         down_read(&device_offload_lock);
1222 release_ctx:
1223         ctx->priv_ctx_rx = NULL;
1224 release_lock:
1225         up_read(&device_offload_lock);
1226 release_netdev:
1227         dev_put(netdev);
1228         return rc;
1229 }
1230
1231 void tls_device_offload_cleanup_rx(struct sock *sk)
1232 {
1233         struct tls_context *tls_ctx = tls_get_ctx(sk);
1234         struct net_device *netdev;
1235
1236         down_read(&device_offload_lock);
1237         netdev = tls_ctx->netdev;
1238         if (!netdev)
1239                 goto out;
1240
1241         netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1242                                         TLS_OFFLOAD_CTX_DIR_RX);
1243
1244         if (tls_ctx->tx_conf != TLS_HW) {
1245                 dev_put(netdev);
1246                 tls_ctx->netdev = NULL;
1247         }
1248 out:
1249         up_read(&device_offload_lock);
1250         tls_sw_release_resources_rx(sk);
1251 }
1252
1253 static int tls_device_down(struct net_device *netdev)
1254 {
1255         struct tls_context *ctx, *tmp;
1256         unsigned long flags;
1257         LIST_HEAD(list);
1258
1259         /* Request a write lock to block new offload attempts */
1260         down_write(&device_offload_lock);
1261
1262         spin_lock_irqsave(&tls_device_lock, flags);
1263         list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1264                 if (ctx->netdev != netdev ||
1265                     !refcount_inc_not_zero(&ctx->refcount))
1266                         continue;
1267
1268                 list_move(&ctx->list, &list);
1269         }
1270         spin_unlock_irqrestore(&tls_device_lock, flags);
1271
1272         list_for_each_entry_safe(ctx, tmp, &list, list) {
1273                 if (ctx->tx_conf == TLS_HW)
1274                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1275                                                         TLS_OFFLOAD_CTX_DIR_TX);
1276                 if (ctx->rx_conf == TLS_HW)
1277                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1278                                                         TLS_OFFLOAD_CTX_DIR_RX);
1279                 WRITE_ONCE(ctx->netdev, NULL);
1280                 smp_mb__before_atomic(); /* pairs with test_and_set_bit() */
1281                 while (test_bit(TLS_RX_SYNC_RUNNING, &ctx->flags))
1282                         usleep_range(10, 200);
1283                 dev_put(netdev);
1284                 list_del_init(&ctx->list);
1285
1286                 if (refcount_dec_and_test(&ctx->refcount))
1287                         tls_device_free_ctx(ctx);
1288         }
1289
1290         up_write(&device_offload_lock);
1291
1292         flush_work(&tls_device_gc_work);
1293
1294         return NOTIFY_DONE;
1295 }
1296
1297 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1298                          void *ptr)
1299 {
1300         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1301
1302         if (!dev->tlsdev_ops &&
1303             !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1304                 return NOTIFY_DONE;
1305
1306         switch (event) {
1307         case NETDEV_REGISTER:
1308         case NETDEV_FEAT_CHANGE:
1309                 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1310                     !dev->tlsdev_ops->tls_dev_resync)
1311                         return NOTIFY_BAD;
1312
1313                 if  (dev->tlsdev_ops &&
1314                      dev->tlsdev_ops->tls_dev_add &&
1315                      dev->tlsdev_ops->tls_dev_del)
1316                         return NOTIFY_DONE;
1317                 else
1318                         return NOTIFY_BAD;
1319         case NETDEV_DOWN:
1320                 return tls_device_down(dev);
1321         }
1322         return NOTIFY_DONE;
1323 }
1324
1325 static struct notifier_block tls_dev_notifier = {
1326         .notifier_call  = tls_dev_event,
1327 };
1328
1329 void __init tls_device_init(void)
1330 {
1331         register_netdevice_notifier(&tls_dev_notifier);
1332 }
1333
1334 void __exit tls_device_cleanup(void)
1335 {
1336         unregister_netdevice_notifier(&tls_dev_notifier);
1337         flush_work(&tls_device_gc_work);
1338         clean_acked_data_flush();
1339 }