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 = kmap(page);
 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         iov.iov_base = kaddr + offset;
 580         iov.iov_len = size;
 581         iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);
 582         rc = tls_push_data(sk, &msg_iter, size,
 583                            flags, TLS_RECORD_TYPE_DATA);
 584         kunmap(page);
 585
 586 out:
 587         release_sock(sk);
 588         mutex_unlock(&tls_ctx->tx_lock);
 589         return rc;
 590 }
 591
 592 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
 593                                        u32 seq, u64 *p_record_sn)
 594 {
 595         u64 record_sn = context->hint_record_sn;
 596         struct tls_record_info *info, *last;
 597
 598         info = context->retransmit_hint;
 599         if (!info ||
 600             before(seq, info->end_seq - info->len)) {
 601                 /* if retransmit_hint is irrelevant start
 602                  * from the beggining of the list
 603                  */
 604                 info = list_first_entry_or_null(&context->records_list,
 605                                                 struct tls_record_info, list);
 606                 if (!info)
 607                         return NULL;
 608                 /* send the start_marker record if seq number is before the
 609                  * tls offload start marker sequence number. This record is
 610                  * required to handle TCP packets which are before TLS offload
 611                  * started.
 612                  *  And if it's not start marker, look if this seq number
 613                  * belongs to the list.
 614                  */
 615                 if (likely(!tls_record_is_start_marker(info))) {
 616                         /* we have the first record, get the last record to see
 617                          * if this seq number belongs to the list.
 618                          */
 619                         last = list_last_entry(&context->records_list,
 620                                                struct tls_record_info, list);
 621
 622                         if (!between(seq, tls_record_start_seq(info),
 623                                      last->end_seq))
 624                                 return NULL;
 625                 }
 626                 record_sn = context->unacked_record_sn;
 627         }
 628
 629         /* We just need the _rcu for the READ_ONCE() */
 630         rcu_read_lock();
 631         list_for_each_entry_from_rcu(info, &context->records_list, list) {
 632                 if (before(seq, info->end_seq)) {
 633                         if (!context->retransmit_hint ||
 634                             after(info->end_seq,
 635                                   context->retransmit_hint->end_seq)) {
 636                                 context->hint_record_sn = record_sn;
 637                                 context->retransmit_hint = info;
 638                         }
 639                         *p_record_sn = record_sn;
 640                         goto exit_rcu_unlock;
 641                 }
 642                 record_sn++;
 643         }
 644         info = NULL;
 645
 646 exit_rcu_unlock:
 647         rcu_read_unlock();
 648         return info;
 649 }
 650 EXPORT_SYMBOL(tls_get_record);
 651
 652 static int tls_device_push_pending_record(struct sock *sk, int flags)
 653 {
 654         struct iov_iter msg_iter;
 655
 656         iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0);
 657         return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA);
 658 }
 659
 660 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 661 {
 662         if (tls_is_partially_sent_record(ctx)) {
 663                 gfp_t sk_allocation = sk->sk_allocation;
 664
 665                 WARN_ON_ONCE(sk->sk_write_pending);
 666
 667                 sk->sk_allocation = GFP_ATOMIC;
 668                 tls_push_partial_record(sk, ctx,
 669                                         MSG_DONTWAIT | MSG_NOSIGNAL |
 670                                         MSG_SENDPAGE_DECRYPTED);
 671                 sk->sk_allocation = sk_allocation;
 672         }
 673 }
 674
 675 static void tls_device_resync_rx(struct tls_context *tls_ctx,
 676                                  struct sock *sk, u32 seq, u8 *rcd_sn)
 677 {
 678         struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
 679         struct net_device *netdev;
 680
 681         if (WARN_ON(test_and_set_bit(TLS_RX_SYNC_RUNNING, &tls_ctx->flags)))
 682                 return;
 683
 684         trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
 685         netdev = READ_ONCE(tls_ctx->netdev);
 686         if (netdev)
 687                 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
 688                                                    TLS_OFFLOAD_CTX_DIR_RX);
 689         clear_bit_unlock(TLS_RX_SYNC_RUNNING, &tls_ctx->flags);
 690         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
 691 }
 692
 693 static bool
 694 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
 695                            s64 resync_req, u32 *seq)
 696 {
 697         u32 is_async = resync_req & RESYNC_REQ_ASYNC;
 698         u32 req_seq = resync_req >> 32;
 699         u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
 700
 701         if (is_async) {
 702                 /* asynchronous stage: log all headers seq such that
 703                  * req_seq <= seq <= end_seq, and wait for real resync request
 704                  */
 705                 if (between(*seq, req_seq, req_end) &&
 706                     resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
 707                         resync_async->log[resync_async->loglen++] = *seq;
 708
 709                 return false;
 710         }
 711
 712         /* synchronous stage: check against the logged entries and
 713          * proceed to check the next entries if no match was found
 714          */
 715         while (resync_async->loglen) {
 716                 if (req_seq == resync_async->log[resync_async->loglen - 1] &&
 717                     atomic64_try_cmpxchg(&resync_async->req,
 718                                          &resync_req, 0)) {
 719                         resync_async->loglen = 0;
 720                         *seq = req_seq;
 721                         return true;
 722                 }
 723                 resync_async->loglen--;
 724         }
 725
 726         if (req_seq == *seq &&
 727             atomic64_try_cmpxchg(&resync_async->req,
 728                                  &resync_req, 0))
 729                 return true;
 730
 731         return false;
 732 }
 733
 734 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
 735 {
 736         struct tls_context *tls_ctx = tls_get_ctx(sk);
 737         struct tls_offload_context_rx *rx_ctx;
 738         u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 739         u32 sock_data, is_req_pending;
 740         struct tls_prot_info *prot;
 741         s64 resync_req;
 742         u32 req_seq;
 743
 744         if (tls_ctx->rx_conf != TLS_HW)
 745                 return;
 746
 747         prot = &tls_ctx->prot_info;
 748         rx_ctx = tls_offload_ctx_rx(tls_ctx);
 749         memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 750
 751         switch (rx_ctx->resync_type) {
 752         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
 753                 resync_req = atomic64_read(&rx_ctx->resync_req);
 754                 req_seq = resync_req >> 32;
 755                 seq += TLS_HEADER_SIZE - 1;
 756                 is_req_pending = resync_req;
 757
 758                 if (likely(!is_req_pending) || req_seq != seq ||
 759                     !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
 760                         return;
 761                 break;
 762         case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
 763                 if (likely(!rx_ctx->resync_nh_do_now))
 764                         return;
 765
 766                 /* head of next rec is already in, note that the sock_inq will
 767                  * include the currently parsed message when called from parser
 768                  */
 769                 sock_data = tcp_inq(sk);
 770                 if (sock_data > rcd_len) {
 771                         trace_tls_device_rx_resync_nh_delay(sk, sock_data,
 772                                                             rcd_len);
 773                         return;
 774                 }
 775
 776                 rx_ctx->resync_nh_do_now = 0;
 777                 seq += rcd_len;
 778                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 779                 break;
 780         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
 781                 resync_req = atomic64_read(&rx_ctx->resync_async->req);
 782                 is_req_pending = resync_req;
 783                 if (likely(!is_req_pending))
 784                         return;
 785
 786                 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
 787                                                 resync_req, &seq))
 788                         return;
 789                 break;
 790         }
 791
 792         tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
 793 }
 794
 795 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
 796                                            struct tls_offload_context_rx *ctx,
 797                                            struct sock *sk, struct sk_buff *skb)
 798 {
 799         struct strp_msg *rxm;
 800
 801         /* device will request resyncs by itself based on stream scan */
 802         if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
 803                 return;
 804         /* already scheduled */
 805         if (ctx->resync_nh_do_now)
 806                 return;
 807         /* seen decrypted fragments since last fully-failed record */
 808         if (ctx->resync_nh_reset) {
 809                 ctx->resync_nh_reset = 0;
 810                 ctx->resync_nh.decrypted_failed = 1;
 811                 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
 812                 return;
 813         }
 814
 815         if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
 816                 return;
 817
 818         /* doing resync, bump the next target in case it fails */
 819         if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
 820                 ctx->resync_nh.decrypted_tgt *= 2;
 821         else
 822                 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
 823
 824         rxm = strp_msg(skb);
 825
 826         /* head of next rec is already in, parser will sync for us */
 827         if (tcp_inq(sk) > rxm->full_len) {
 828                 trace_tls_device_rx_resync_nh_schedule(sk);
 829                 ctx->resync_nh_do_now = 1;
 830         } else {
 831                 struct tls_prot_info *prot = &tls_ctx->prot_info;
 832                 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 833
 834                 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 835                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 836
 837                 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
 838                                      rcd_sn);
 839         }
 840 }
 841
 842 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
 843 {
 844         struct strp_msg *rxm = strp_msg(skb);
 845         int err = 0, offset = rxm->offset, copy, nsg, data_len, pos;
 846         struct sk_buff *skb_iter, *unused;
 847         struct scatterlist sg[1];
 848         char *orig_buf, *buf;
 849
 850         orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE +
 851                            TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation);
 852         if (!orig_buf)
 853                 return -ENOMEM;
 854         buf = orig_buf;
 855
 856         nsg = skb_cow_data(skb, 0, &unused);
 857         if (unlikely(nsg < 0)) {
 858                 err = nsg;
 859                 goto free_buf;
 860         }
 861
 862         sg_init_table(sg, 1);
 863         sg_set_buf(&sg[0], buf,
 864                    rxm->full_len + TLS_HEADER_SIZE +
 865                    TLS_CIPHER_AES_GCM_128_IV_SIZE);
 866         err = skb_copy_bits(skb, offset, buf,
 867                             TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
 868         if (err)
 869                 goto free_buf;
 870
 871         /* We are interested only in the decrypted data not the auth */
 872         err = decrypt_skb(sk, skb, sg);
 873         if (err != -EBADMSG)
 874                 goto free_buf;
 875         else
 876                 err = 0;
 877
 878         data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE;
 879
 880         if (skb_pagelen(skb) > offset) {
 881                 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 882
 883                 if (skb->decrypted) {
 884                         err = skb_store_bits(skb, offset, buf, copy);
 885                         if (err)
 886                                 goto free_buf;
 887                 }
 888
 889                 offset += copy;
 890                 buf += copy;
 891         }
 892
 893         pos = skb_pagelen(skb);
 894         skb_walk_frags(skb, skb_iter) {
 895                 int frag_pos;
 896
 897                 /* Practically all frags must belong to msg if reencrypt
 898                  * is needed with current strparser and coalescing logic,
 899                  * but strparser may "get optimized", so let's be safe.
 900                  */
 901                 if (pos + skb_iter->len <= offset)
 902                         goto done_with_frag;
 903                 if (pos >= data_len + rxm->offset)
 904                         break;
 905
 906                 frag_pos = offset - pos;
 907                 copy = min_t(int, skb_iter->len - frag_pos,
 908                              data_len + rxm->offset - offset);
 909
 910                 if (skb_iter->decrypted) {
 911                         err = skb_store_bits(skb_iter, frag_pos, buf, copy);
 912                         if (err)
 913                                 goto free_buf;
 914                 }
 915
 916                 offset += copy;
 917                 buf += copy;
 918 done_with_frag:
 919                 pos += skb_iter->len;
 920         }
 921
 922 free_buf:
 923         kfree(orig_buf);
 924         return err;
 925 }
 926
 927 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx,
 928                          struct sk_buff *skb, struct strp_msg *rxm)
 929 {
 930         struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
 931         int is_decrypted = skb->decrypted;
 932         int is_encrypted = !is_decrypted;
 933         struct sk_buff *skb_iter;
 934
 935         /* Check if all the data is decrypted already */
 936         skb_walk_frags(skb, skb_iter) {
 937                 is_decrypted &= skb_iter->decrypted;
 938                 is_encrypted &= !skb_iter->decrypted;
 939         }
 940
 941         trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
 942                                    tls_ctx->rx.rec_seq, rxm->full_len,
 943                                    is_encrypted, is_decrypted);
 944
 945         ctx->sw.decrypted |= is_decrypted;
 946
 947         /* Return immediately if the record is either entirely plaintext or
 948          * entirely ciphertext. Otherwise handle reencrypt partially decrypted
 949          * record.
 950          */
 951         if (is_decrypted) {
 952                 ctx->resync_nh_reset = 1;
 953                 return 0;
 954         }
 955         if (is_encrypted) {
 956                 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
 957                 return 0;
 958         }
 959
 960         ctx->resync_nh_reset = 1;
 961         return tls_device_reencrypt(sk, skb);
 962 }
 963
 964 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
 965                               struct net_device *netdev)
 966 {
 967         if (sk->sk_destruct != tls_device_sk_destruct) {
 968                 refcount_set(&ctx->refcount, 1);
 969                 dev_hold(netdev);
 970                 ctx->netdev = netdev;
 971                 spin_lock_irq(&tls_device_lock);
 972                 list_add_tail(&ctx->list, &tls_device_list);
 973                 spin_unlock_irq(&tls_device_lock);
 974
 975                 ctx->sk_destruct = sk->sk_destruct;
 976                 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
 977         }
 978 }
 979
 980 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
 981 {
 982         u16 nonce_size, tag_size, iv_size, rec_seq_size;
 983         struct tls_context *tls_ctx = tls_get_ctx(sk);
 984         struct tls_prot_info *prot = &tls_ctx->prot_info;
 985         struct tls_record_info *start_marker_record;
 986         struct tls_offload_context_tx *offload_ctx;
 987         struct tls_crypto_info *crypto_info;
 988         struct net_device *netdev;
 989         char *iv, *rec_seq;
 990         struct sk_buff *skb;
 991         __be64 rcd_sn;
 992         int rc;
 993
 994         if (!ctx)
 995                 return -EINVAL;
 996
 997         if (ctx->priv_ctx_tx)
 998                 return -EEXIST;
 999
1000         start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1001         if (!start_marker_record)
1002                 return -ENOMEM;
1003
1004         offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
1005         if (!offload_ctx) {
1006                 rc = -ENOMEM;
1007                 goto free_marker_record;
1008         }
1009
1010         crypto_info = &ctx->crypto_send.info;
1011         if (crypto_info->version != TLS_1_2_VERSION) {
1012                 rc = -EOPNOTSUPP;
1013                 goto free_offload_ctx;
1014         }
1015
1016         switch (crypto_info->cipher_type) {
1017         case TLS_CIPHER_AES_GCM_128:
1018                 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1019                 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
1020                 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1021                 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
1022                 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
1023                 rec_seq =
1024                  ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
1025                 break;
1026         default:
1027                 rc = -EINVAL;
1028                 goto free_offload_ctx;
1029         }
1030
1031         /* Sanity-check the rec_seq_size for stack allocations */
1032         if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
1033                 rc = -EINVAL;
1034                 goto free_offload_ctx;
1035         }
1036
1037         prot->version = crypto_info->version;
1038         prot->cipher_type = crypto_info->cipher_type;
1039         prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
1040         prot->tag_size = tag_size;
1041         prot->overhead_size = prot->prepend_size + prot->tag_size;
1042         prot->iv_size = iv_size;
1043         ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
1044                              GFP_KERNEL);
1045         if (!ctx->tx.iv) {
1046                 rc = -ENOMEM;
1047                 goto free_offload_ctx;
1048         }
1049
1050         memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
1051
1052         prot->rec_seq_size = rec_seq_size;
1053         ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
1054         if (!ctx->tx.rec_seq) {
1055                 rc = -ENOMEM;
1056                 goto free_iv;
1057         }
1058
1059         rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1060         if (rc)
1061                 goto free_rec_seq;
1062
1063         /* start at rec_seq - 1 to account for the start marker record */
1064         memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1065         offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1066
1067         start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1068         start_marker_record->len = 0;
1069         start_marker_record->num_frags = 0;
1070
1071         INIT_LIST_HEAD(&offload_ctx->records_list);
1072         list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1073         spin_lock_init(&offload_ctx->lock);
1074         sg_init_table(offload_ctx->sg_tx_data,
1075                       ARRAY_SIZE(offload_ctx->sg_tx_data));
1076
1077         clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1078         ctx->push_pending_record = tls_device_push_pending_record;
1079
1080         /* TLS offload is greatly simplified if we don't send
1081          * SKBs where only part of the payload needs to be encrypted.
1082          * So mark the last skb in the write queue as end of record.
1083          */
1084         skb = tcp_write_queue_tail(sk);
1085         if (skb)
1086                 TCP_SKB_CB(skb)->eor = 1;
1087
1088         netdev = get_netdev_for_sock(sk);
1089         if (!netdev) {
1090                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1091                 rc = -EINVAL;
1092                 goto disable_cad;
1093         }
1094
1095         if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1096                 rc = -EOPNOTSUPP;
1097                 goto release_netdev;
1098         }
1099
1100         /* Avoid offloading if the device is down
1101          * We don't want to offload new flows after
1102          * the NETDEV_DOWN event
1103          *
1104          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1105          * handler thus protecting from the device going down before
1106          * ctx was added to tls_device_list.
1107          */
1108         down_read(&device_offload_lock);
1109         if (!(netdev->flags & IFF_UP)) {
1110                 rc = -EINVAL;
1111                 goto release_lock;
1112         }
1113
1114         ctx->priv_ctx_tx = offload_ctx;
1115         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1116                                              &ctx->crypto_send.info,
1117                                              tcp_sk(sk)->write_seq);
1118         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1119                                      tcp_sk(sk)->write_seq, rec_seq, rc);
1120         if (rc)
1121                 goto release_lock;
1122
1123         tls_device_attach(ctx, sk, netdev);
1124         up_read(&device_offload_lock);
1125
1126         /* following this assignment tls_is_sk_tx_device_offloaded
1127          * will return true and the context might be accessed
1128          * by the netdev's xmit function.
1129          */
1130         smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1131         dev_put(netdev);
1132
1133         return 0;
1134
1135 release_lock:
1136         up_read(&device_offload_lock);
1137 release_netdev:
1138         dev_put(netdev);
1139 disable_cad:
1140         clean_acked_data_disable(inet_csk(sk));
1141         crypto_free_aead(offload_ctx->aead_send);
1142 free_rec_seq:
1143         kfree(ctx->tx.rec_seq);
1144 free_iv:
1145         kfree(ctx->tx.iv);
1146 free_offload_ctx:
1147         kfree(offload_ctx);
1148         ctx->priv_ctx_tx = NULL;
1149 free_marker_record:
1150         kfree(start_marker_record);
1151         return rc;
1152 }
1153
1154 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1155 {
1156         struct tls12_crypto_info_aes_gcm_128 *info;
1157         struct tls_offload_context_rx *context;
1158         struct net_device *netdev;
1159         int rc = 0;
1160
1161         if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1162                 return -EOPNOTSUPP;
1163
1164         netdev = get_netdev_for_sock(sk);
1165         if (!netdev) {
1166                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1167                 return -EINVAL;
1168         }
1169
1170         if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1171                 rc = -EOPNOTSUPP;
1172                 goto release_netdev;
1173         }
1174
1175         /* Avoid offloading if the device is down
1176          * We don't want to offload new flows after
1177          * the NETDEV_DOWN event
1178          *
1179          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1180          * handler thus protecting from the device going down before
1181          * ctx was added to tls_device_list.
1182          */
1183         down_read(&device_offload_lock);
1184         if (!(netdev->flags & IFF_UP)) {
1185                 rc = -EINVAL;
1186                 goto release_lock;
1187         }
1188
1189         context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1190         if (!context) {
1191                 rc = -ENOMEM;
1192                 goto release_lock;
1193         }
1194         context->resync_nh_reset = 1;
1195
1196         ctx->priv_ctx_rx = context;
1197         rc = tls_set_sw_offload(sk, ctx, 0);
1198         if (rc)
1199                 goto release_ctx;
1200
1201         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1202                                              &ctx->crypto_recv.info,
1203                                              tcp_sk(sk)->copied_seq);
1204         info = (void *)&ctx->crypto_recv.info;
1205         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1206                                      tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1207         if (rc)
1208                 goto free_sw_resources;
1209
1210         tls_device_attach(ctx, sk, netdev);
1211         up_read(&device_offload_lock);
1212
1213         dev_put(netdev);
1214
1215         return 0;
1216
1217 free_sw_resources:
1218         up_read(&device_offload_lock);
1219         tls_sw_free_resources_rx(sk);
1220         down_read(&device_offload_lock);
1221 release_ctx:
1222         ctx->priv_ctx_rx = NULL;
1223 release_lock:
1224         up_read(&device_offload_lock);
1225 release_netdev:
1226         dev_put(netdev);
1227         return rc;
1228 }
1229
1230 void tls_device_offload_cleanup_rx(struct sock *sk)
1231 {
1232         struct tls_context *tls_ctx = tls_get_ctx(sk);
1233         struct net_device *netdev;
1234
1235         down_read(&device_offload_lock);
1236         netdev = tls_ctx->netdev;
1237         if (!netdev)
1238                 goto out;
1239
1240         netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1241                                         TLS_OFFLOAD_CTX_DIR_RX);
1242
1243         if (tls_ctx->tx_conf != TLS_HW) {
1244                 dev_put(netdev);
1245                 tls_ctx->netdev = NULL;
1246         }
1247 out:
1248         up_read(&device_offload_lock);
1249         tls_sw_release_resources_rx(sk);
1250 }
1251
1252 static int tls_device_down(struct net_device *netdev)
1253 {
1254         struct tls_context *ctx, *tmp;
1255         unsigned long flags;
1256         LIST_HEAD(list);
1257
1258         /* Request a write lock to block new offload attempts */
1259         down_write(&device_offload_lock);
1260
1261         spin_lock_irqsave(&tls_device_lock, flags);
1262         list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1263                 if (ctx->netdev != netdev ||
1264                     !refcount_inc_not_zero(&ctx->refcount))
1265                         continue;
1266
1267                 list_move(&ctx->list, &list);
1268         }
1269         spin_unlock_irqrestore(&tls_device_lock, flags);
1270
1271         list_for_each_entry_safe(ctx, tmp, &list, list) {
1272                 if (ctx->tx_conf == TLS_HW)
1273                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1274                                                         TLS_OFFLOAD_CTX_DIR_TX);
1275                 if (ctx->rx_conf == TLS_HW)
1276                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1277                                                         TLS_OFFLOAD_CTX_DIR_RX);
1278                 WRITE_ONCE(ctx->netdev, NULL);
1279                 smp_mb__before_atomic(); /* pairs with test_and_set_bit() */
1280                 while (test_bit(TLS_RX_SYNC_RUNNING, &ctx->flags))
1281                         usleep_range(10, 200);
1282                 dev_put(netdev);
1283                 list_del_init(&ctx->list);
1284
1285                 if (refcount_dec_and_test(&ctx->refcount))
1286                         tls_device_free_ctx(ctx);
1287         }
1288
1289         up_write(&device_offload_lock);
1290
1291         flush_work(&tls_device_gc_work);
1292
1293         return NOTIFY_DONE;
1294 }
1295
1296 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1297                          void *ptr)
1298 {
1299         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1300
1301         if (!dev->tlsdev_ops &&
1302             !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1303                 return NOTIFY_DONE;
1304
1305         switch (event) {
1306         case NETDEV_REGISTER:
1307         case NETDEV_FEAT_CHANGE:
1308                 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1309                     !dev->tlsdev_ops->tls_dev_resync)
1310                         return NOTIFY_BAD;
1311
1312                 if  (dev->tlsdev_ops &&
1313                      dev->tlsdev_ops->tls_dev_add &&
1314                      dev->tlsdev_ops->tls_dev_del)
1315                         return NOTIFY_DONE;
1316                 else
1317                         return NOTIFY_BAD;
1318         case NETDEV_DOWN:
1319                 return tls_device_down(dev);
1320         }
1321         return NOTIFY_DONE;
1322 }
1323
1324 static struct notifier_block tls_dev_notifier = {
1325         .notifier_call  = tls_dev_event,
1326 };
1327
1328 void __init tls_device_init(void)
1329 {
1330         register_netdevice_notifier(&tls_dev_notifier);
1331 }
1332
1333 void __exit tls_device_cleanup(void)
1334 {
1335         unregister_netdevice_notifier(&tls_dev_notifier);
1336         flush_work(&tls_device_gc_work);
1337         clean_acked_data_flush();
1338 }