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 LIST_HEAD(tls_device_down_list);
  54 static DEFINE_SPINLOCK(tls_device_lock);
  55
  56 static void tls_device_free_ctx(struct tls_context *ctx)
  57 {
  58         if (ctx->tx_conf == TLS_HW) {
  59                 kfree(tls_offload_ctx_tx(ctx));
  60                 kfree(ctx->tx.rec_seq);
  61                 kfree(ctx->tx.iv);
  62         }
  63
  64         if (ctx->rx_conf == TLS_HW)
  65                 kfree(tls_offload_ctx_rx(ctx));
  66
  67         tls_ctx_free(NULL, ctx);
  68 }
  69
  70 static void tls_device_gc_task(struct work_struct *work)
  71 {
  72         struct tls_context *ctx, *tmp;
  73         unsigned long flags;
  74         LIST_HEAD(gc_list);
  75
  76         spin_lock_irqsave(&tls_device_lock, flags);
  77         list_splice_init(&tls_device_gc_list, &gc_list);
  78         spin_unlock_irqrestore(&tls_device_lock, flags);
  79
  80         list_for_each_entry_safe(ctx, tmp, &gc_list, list) {
  81                 struct net_device *netdev = ctx->netdev;
  82
  83                 if (netdev && ctx->tx_conf == TLS_HW) {
  84                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
  85                                                         TLS_OFFLOAD_CTX_DIR_TX);
  86                         dev_put(netdev);
  87                         ctx->netdev = NULL;
  88                 }
  89
  90                 list_del(&ctx->list);
  91                 tls_device_free_ctx(ctx);
  92         }
  93 }
  94
  95 static void tls_device_queue_ctx_destruction(struct tls_context *ctx)
  96 {
  97         unsigned long flags;
  98
  99         spin_lock_irqsave(&tls_device_lock, flags);
 100         list_move_tail(&ctx->list, &tls_device_gc_list);
 101
 102         /* schedule_work inside the spinlock
 103          * to make sure tls_device_down waits for that work.
 104          */
 105         schedule_work(&tls_device_gc_work);
 106
 107         spin_unlock_irqrestore(&tls_device_lock, flags);
 108 }
 109
 110 /* We assume that the socket is already connected */
 111 static struct net_device *get_netdev_for_sock(struct sock *sk)
 112 {
 113         struct dst_entry *dst = sk_dst_get(sk);
 114         struct net_device *netdev = NULL;
 115
 116         if (likely(dst)) {
 117                 netdev = netdev_sk_get_lowest_dev(dst->dev, sk);
 118                 dev_hold(netdev);
 119         }
 120
 121         dst_release(dst);
 122
 123         return netdev;
 124 }
 125
 126 static void destroy_record(struct tls_record_info *record)
 127 {
 128         int i;
 129
 130         for (i = 0; i < record->num_frags; i++)
 131                 __skb_frag_unref(&record->frags[i], false);
 132         kfree(record);
 133 }
 134
 135 static void delete_all_records(struct tls_offload_context_tx *offload_ctx)
 136 {
 137         struct tls_record_info *info, *temp;
 138
 139         list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) {
 140                 list_del(&info->list);
 141                 destroy_record(info);
 142         }
 143
 144         offload_ctx->retransmit_hint = NULL;
 145 }
 146
 147 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq)
 148 {
 149         struct tls_context *tls_ctx = tls_get_ctx(sk);
 150         struct tls_record_info *info, *temp;
 151         struct tls_offload_context_tx *ctx;
 152         u64 deleted_records = 0;
 153         unsigned long flags;
 154
 155         if (!tls_ctx)
 156                 return;
 157
 158         ctx = tls_offload_ctx_tx(tls_ctx);
 159
 160         spin_lock_irqsave(&ctx->lock, flags);
 161         info = ctx->retransmit_hint;
 162         if (info && !before(acked_seq, info->end_seq))
 163                 ctx->retransmit_hint = NULL;
 164
 165         list_for_each_entry_safe(info, temp, &ctx->records_list, list) {
 166                 if (before(acked_seq, info->end_seq))
 167                         break;
 168                 list_del(&info->list);
 169
 170                 destroy_record(info);
 171                 deleted_records++;
 172         }
 173
 174         ctx->unacked_record_sn += deleted_records;
 175         spin_unlock_irqrestore(&ctx->lock, flags);
 176 }
 177
 178 /* At this point, there should be no references on this
 179  * socket and no in-flight SKBs associated with this
 180  * socket, so it is safe to free all the resources.
 181  */
 182 void tls_device_sk_destruct(struct sock *sk)
 183 {
 184         struct tls_context *tls_ctx = tls_get_ctx(sk);
 185         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 186
 187         tls_ctx->sk_destruct(sk);
 188
 189         if (tls_ctx->tx_conf == TLS_HW) {
 190                 if (ctx->open_record)
 191                         destroy_record(ctx->open_record);
 192                 delete_all_records(ctx);
 193                 crypto_free_aead(ctx->aead_send);
 194                 clean_acked_data_disable(inet_csk(sk));
 195         }
 196
 197         if (refcount_dec_and_test(&tls_ctx->refcount))
 198                 tls_device_queue_ctx_destruction(tls_ctx);
 199 }
 200 EXPORT_SYMBOL_GPL(tls_device_sk_destruct);
 201
 202 void tls_device_free_resources_tx(struct sock *sk)
 203 {
 204         struct tls_context *tls_ctx = tls_get_ctx(sk);
 205
 206         tls_free_partial_record(sk, tls_ctx);
 207 }
 208
 209 void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq)
 210 {
 211         struct tls_context *tls_ctx = tls_get_ctx(sk);
 212
 213         trace_tls_device_tx_resync_req(sk, got_seq, exp_seq);
 214         WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags));
 215 }
 216 EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request);
 217
 218 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
 219                                  u32 seq)
 220 {
 221         struct net_device *netdev;
 222         struct sk_buff *skb;
 223         int err = 0;
 224         u8 *rcd_sn;
 225
 226         skb = tcp_write_queue_tail(sk);
 227         if (skb)
 228                 TCP_SKB_CB(skb)->eor = 1;
 229
 230         rcd_sn = tls_ctx->tx.rec_seq;
 231
 232         trace_tls_device_tx_resync_send(sk, seq, rcd_sn);
 233         down_read(&device_offload_lock);
 234         netdev = tls_ctx->netdev;
 235         if (netdev)
 236                 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq,
 237                                                          rcd_sn,
 238                                                          TLS_OFFLOAD_CTX_DIR_TX);
 239         up_read(&device_offload_lock);
 240         if (err)
 241                 return;
 242
 243         clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
 244 }
 245
 246 static void tls_append_frag(struct tls_record_info *record,
 247                             struct page_frag *pfrag,
 248                             int size)
 249 {
 250         skb_frag_t *frag;
 251
 252         frag = &record->frags[record->num_frags - 1];
 253         if (skb_frag_page(frag) == pfrag->page &&
 254             skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
 255                 skb_frag_size_add(frag, size);
 256         } else {
 257                 ++frag;
 258                 __skb_frag_set_page(frag, pfrag->page);
 259                 skb_frag_off_set(frag, pfrag->offset);
 260                 skb_frag_size_set(frag, size);
 261                 ++record->num_frags;
 262                 get_page(pfrag->page);
 263         }
 264
 265         pfrag->offset += size;
 266         record->len += size;
 267 }
 268
 269 static int tls_push_record(struct sock *sk,
 270                            struct tls_context *ctx,
 271                            struct tls_offload_context_tx *offload_ctx,
 272                            struct tls_record_info *record,
 273                            int flags)
 274 {
 275         struct tls_prot_info *prot = &ctx->prot_info;
 276         struct tcp_sock *tp = tcp_sk(sk);
 277         skb_frag_t *frag;
 278         int i;
 279
 280         record->end_seq = tp->write_seq + record->len;
 281         list_add_tail_rcu(&record->list, &offload_ctx->records_list);
 282         offload_ctx->open_record = NULL;
 283
 284         if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
 285                 tls_device_resync_tx(sk, ctx, tp->write_seq);
 286
 287         tls_advance_record_sn(sk, prot, &ctx->tx);
 288
 289         for (i = 0; i < record->num_frags; i++) {
 290                 frag = &record->frags[i];
 291                 sg_unmark_end(&offload_ctx->sg_tx_data[i]);
 292                 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
 293                             skb_frag_size(frag), skb_frag_off(frag));
 294                 sk_mem_charge(sk, skb_frag_size(frag));
 295                 get_page(skb_frag_page(frag));
 296         }
 297         sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
 298
 299         /* all ready, send */
 300         return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
 301 }
 302
 303 static int tls_device_record_close(struct sock *sk,
 304                                    struct tls_context *ctx,
 305                                    struct tls_record_info *record,
 306                                    struct page_frag *pfrag,
 307                                    unsigned char record_type)
 308 {
 309         struct tls_prot_info *prot = &ctx->prot_info;
 310         int ret;
 311
 312         /* append tag
 313          * device will fill in the tag, we just need to append a placeholder
 314          * use socket memory to improve coalescing (re-using a single buffer
 315          * increases frag count)
 316          * if we can't allocate memory now, steal some back from data
 317          */
 318         if (likely(skb_page_frag_refill(prot->tag_size, pfrag,
 319                                         sk->sk_allocation))) {
 320                 ret = 0;
 321                 tls_append_frag(record, pfrag, prot->tag_size);
 322         } else {
 323                 ret = prot->tag_size;
 324                 if (record->len <= prot->overhead_size)
 325                         return -ENOMEM;
 326         }
 327
 328         /* fill prepend */
 329         tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
 330                          record->len - prot->overhead_size,
 331                          record_type);
 332         return ret;
 333 }
 334
 335 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
 336                                  struct page_frag *pfrag,
 337                                  size_t prepend_size)
 338 {
 339         struct tls_record_info *record;
 340         skb_frag_t *frag;
 341
 342         record = kmalloc(sizeof(*record), GFP_KERNEL);
 343         if (!record)
 344                 return -ENOMEM;
 345
 346         frag = &record->frags[0];
 347         __skb_frag_set_page(frag, pfrag->page);
 348         skb_frag_off_set(frag, pfrag->offset);
 349         skb_frag_size_set(frag, prepend_size);
 350
 351         get_page(pfrag->page);
 352         pfrag->offset += prepend_size;
 353
 354         record->num_frags = 1;
 355         record->len = prepend_size;
 356         offload_ctx->open_record = record;
 357         return 0;
 358 }
 359
 360 static int tls_do_allocation(struct sock *sk,
 361                              struct tls_offload_context_tx *offload_ctx,
 362                              struct page_frag *pfrag,
 363                              size_t prepend_size)
 364 {
 365         int ret;
 366
 367         if (!offload_ctx->open_record) {
 368                 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
 369                                                    sk->sk_allocation))) {
 370                         READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
 371                         sk_stream_moderate_sndbuf(sk);
 372                         return -ENOMEM;
 373                 }
 374
 375                 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
 376                 if (ret)
 377                         return ret;
 378
 379                 if (pfrag->size > pfrag->offset)
 380                         return 0;
 381         }
 382
 383         if (!sk_page_frag_refill(sk, pfrag))
 384                 return -ENOMEM;
 385
 386         return 0;
 387 }
 388
 389 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
 390 {
 391         size_t pre_copy, nocache;
 392
 393         pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
 394         if (pre_copy) {
 395                 pre_copy = min(pre_copy, bytes);
 396                 if (copy_from_iter(addr, pre_copy, i) != pre_copy)
 397                         return -EFAULT;
 398                 bytes -= pre_copy;
 399                 addr += pre_copy;
 400         }
 401
 402         nocache = round_down(bytes, SMP_CACHE_BYTES);
 403         if (copy_from_iter_nocache(addr, nocache, i) != nocache)
 404                 return -EFAULT;
 405         bytes -= nocache;
 406         addr += nocache;
 407
 408         if (bytes && copy_from_iter(addr, bytes, i) != bytes)
 409                 return -EFAULT;
 410
 411         return 0;
 412 }
 413
 414 static int tls_push_data(struct sock *sk,
 415                          struct iov_iter *msg_iter,
 416                          size_t size, int flags,
 417                          unsigned char record_type)
 418 {
 419         struct tls_context *tls_ctx = tls_get_ctx(sk);
 420         struct tls_prot_info *prot = &tls_ctx->prot_info;
 421         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 422         struct tls_record_info *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         bool more = false;
 428         bool done = false;
 429         int copy, rc = 0;
 430         long timeo;
 431
 432         if (flags &
 433             ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
 434                 return -EOPNOTSUPP;
 435
 436         if (unlikely(sk->sk_err))
 437                 return -sk->sk_err;
 438
 439         flags |= MSG_SENDPAGE_DECRYPTED;
 440         tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST;
 441
 442         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
 443         if (tls_is_partially_sent_record(tls_ctx)) {
 444                 rc = tls_push_partial_record(sk, tls_ctx, flags);
 445                 if (rc < 0)
 446                         return rc;
 447         }
 448
 449         pfrag = sk_page_frag(sk);
 450
 451         /* TLS_HEADER_SIZE is not counted as part of the TLS record, and
 452          * we need to leave room for an authentication tag.
 453          */
 454         max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
 455                               prot->prepend_size;
 456         do {
 457                 rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
 458                 if (unlikely(rc)) {
 459                         rc = sk_stream_wait_memory(sk, &timeo);
 460                         if (!rc)
 461                                 continue;
 462
 463                         record = ctx->open_record;
 464                         if (!record)
 465                                 break;
 466 handle_error:
 467                         if (record_type != TLS_RECORD_TYPE_DATA) {
 468                                 /* avoid sending partial
 469                                  * record with type !=
 470                                  * application_data
 471                                  */
 472                                 size = orig_size;
 473                                 destroy_record(record);
 474                                 ctx->open_record = NULL;
 475                         } else if (record->len > prot->prepend_size) {
 476                                 goto last_record;
 477                         }
 478
 479                         break;
 480                 }
 481
 482                 record = ctx->open_record;
 483                 copy = min_t(size_t, size, (pfrag->size - pfrag->offset));
 484                 copy = min_t(size_t, copy, (max_open_record_len - record->len));
 485
 486                 if (copy) {
 487                         rc = tls_device_copy_data(page_address(pfrag->page) +
 488                                                   pfrag->offset, copy, msg_iter);
 489                         if (rc)
 490                                 goto handle_error;
 491                         tls_append_frag(record, pfrag, copy);
 492                 }
 493
 494                 size -= copy;
 495                 if (!size) {
 496 last_record:
 497                         tls_push_record_flags = flags;
 498                         if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) {
 499                                 more = true;
 500                                 break;
 501                         }
 502
 503                         done = true;
 504                 }
 505
 506                 if (done || record->len >= max_open_record_len ||
 507                     (record->num_frags >= MAX_SKB_FRAGS - 1)) {
 508                         rc = tls_device_record_close(sk, tls_ctx, record,
 509                                                      pfrag, record_type);
 510                         if (rc) {
 511                                 if (rc > 0) {
 512                                         size += rc;
 513                                 } else {
 514                                         size = orig_size;
 515                                         destroy_record(record);
 516                                         ctx->open_record = NULL;
 517                                         break;
 518                                 }
 519                         }
 520
 521                         rc = tls_push_record(sk,
 522                                              tls_ctx,
 523                                              ctx,
 524                                              record,
 525                                              tls_push_record_flags);
 526                         if (rc < 0)
 527                                 break;
 528                 }
 529         } while (!done);
 530
 531         tls_ctx->pending_open_record_frags = more;
 532
 533         if (orig_size - size > 0)
 534                 rc = orig_size - size;
 535
 536         return rc;
 537 }
 538
 539 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 540 {
 541         unsigned char record_type = TLS_RECORD_TYPE_DATA;
 542         struct tls_context *tls_ctx = tls_get_ctx(sk);
 543         int rc;
 544
 545         mutex_lock(&tls_ctx->tx_lock);
 546         lock_sock(sk);
 547
 548         if (unlikely(msg->msg_controllen)) {
 549                 rc = tls_proccess_cmsg(sk, msg, &record_type);
 550                 if (rc)
 551                         goto out;
 552         }
 553
 554         rc = tls_push_data(sk, &msg->msg_iter, size,
 555                            msg->msg_flags, record_type);
 556
 557 out:
 558         release_sock(sk);
 559         mutex_unlock(&tls_ctx->tx_lock);
 560         return rc;
 561 }
 562
 563 int tls_device_sendpage(struct sock *sk, struct page *page,
 564                         int offset, size_t size, int flags)
 565 {
 566         struct tls_context *tls_ctx = tls_get_ctx(sk);
 567         struct iov_iter msg_iter;
 568         char *kaddr;
 569         struct kvec iov;
 570         int rc;
 571
 572         if (flags & MSG_SENDPAGE_NOTLAST)
 573                 flags |= MSG_MORE;
 574
 575         mutex_lock(&tls_ctx->tx_lock);
 576         lock_sock(sk);
 577
 578         if (flags & MSG_OOB) {
 579                 rc = -EOPNOTSUPP;
 580                 goto out;
 581         }
 582
 583         kaddr = kmap(page);
 584         iov.iov_base = kaddr + offset;
 585         iov.iov_len = size;
 586         iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);
 587         rc = tls_push_data(sk, &msg_iter, size,
 588                            flags, TLS_RECORD_TYPE_DATA);
 589         kunmap(page);
 590
 591 out:
 592         release_sock(sk);
 593         mutex_unlock(&tls_ctx->tx_lock);
 594         return rc;
 595 }
 596
 597 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
 598                                        u32 seq, u64 *p_record_sn)
 599 {
 600         u64 record_sn = context->hint_record_sn;
 601         struct tls_record_info *info, *last;
 602
 603         info = context->retransmit_hint;
 604         if (!info ||
 605             before(seq, info->end_seq - info->len)) {
 606                 /* if retransmit_hint is irrelevant start
 607                  * from the beginning of the list
 608                  */
 609                 info = list_first_entry_or_null(&context->records_list,
 610                                                 struct tls_record_info, list);
 611                 if (!info)
 612                         return NULL;
 613                 /* send the start_marker record if seq number is before the
 614                  * tls offload start marker sequence number. This record is
 615                  * required to handle TCP packets which are before TLS offload
 616                  * started.
 617                  *  And if it's not start marker, look if this seq number
 618                  * belongs to the list.
 619                  */
 620                 if (likely(!tls_record_is_start_marker(info))) {
 621                         /* we have the first record, get the last record to see
 622                          * if this seq number belongs to the list.
 623                          */
 624                         last = list_last_entry(&context->records_list,
 625                                                struct tls_record_info, list);
 626
 627                         if (!between(seq, tls_record_start_seq(info),
 628                                      last->end_seq))
 629                                 return NULL;
 630                 }
 631                 record_sn = context->unacked_record_sn;
 632         }
 633
 634         /* We just need the _rcu for the READ_ONCE() */
 635         rcu_read_lock();
 636         list_for_each_entry_from_rcu(info, &context->records_list, list) {
 637                 if (before(seq, info->end_seq)) {
 638                         if (!context->retransmit_hint ||
 639                             after(info->end_seq,
 640                                   context->retransmit_hint->end_seq)) {
 641                                 context->hint_record_sn = record_sn;
 642                                 context->retransmit_hint = info;
 643                         }
 644                         *p_record_sn = record_sn;
 645                         goto exit_rcu_unlock;
 646                 }
 647                 record_sn++;
 648         }
 649         info = NULL;
 650
 651 exit_rcu_unlock:
 652         rcu_read_unlock();
 653         return info;
 654 }
 655 EXPORT_SYMBOL(tls_get_record);
 656
 657 static int tls_device_push_pending_record(struct sock *sk, int flags)
 658 {
 659         struct iov_iter msg_iter;
 660
 661         iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0);
 662         return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA);
 663 }
 664
 665 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 666 {
 667         if (tls_is_partially_sent_record(ctx)) {
 668                 gfp_t sk_allocation = sk->sk_allocation;
 669
 670                 WARN_ON_ONCE(sk->sk_write_pending);
 671
 672                 sk->sk_allocation = GFP_ATOMIC;
 673                 tls_push_partial_record(sk, ctx,
 674                                         MSG_DONTWAIT | MSG_NOSIGNAL |
 675                                         MSG_SENDPAGE_DECRYPTED);
 676                 sk->sk_allocation = sk_allocation;
 677         }
 678 }
 679
 680 static void tls_device_resync_rx(struct tls_context *tls_ctx,
 681                                  struct sock *sk, u32 seq, u8 *rcd_sn)
 682 {
 683         struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
 684         struct net_device *netdev;
 685
 686         trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
 687         rcu_read_lock();
 688         netdev = READ_ONCE(tls_ctx->netdev);
 689         if (netdev)
 690                 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
 691                                                    TLS_OFFLOAD_CTX_DIR_RX);
 692         rcu_read_unlock();
 693         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
 694 }
 695
 696 static bool
 697 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
 698                            s64 resync_req, u32 *seq, u16 *rcd_delta)
 699 {
 700         u32 is_async = resync_req & RESYNC_REQ_ASYNC;
 701         u32 req_seq = resync_req >> 32;
 702         u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
 703         u16 i;
 704
 705         *rcd_delta = 0;
 706
 707         if (is_async) {
 708                 /* shouldn't get to wraparound:
 709                  * too long in async stage, something bad happened
 710                  */
 711                 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
 712                         return false;
 713
 714                 /* asynchronous stage: log all headers seq such that
 715                  * req_seq <= seq <= end_seq, and wait for real resync request
 716                  */
 717                 if (before(*seq, req_seq))
 718                         return false;
 719                 if (!after(*seq, req_end) &&
 720                     resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
 721                         resync_async->log[resync_async->loglen++] = *seq;
 722
 723                 resync_async->rcd_delta++;
 724
 725                 return false;
 726         }
 727
 728         /* synchronous stage: check against the logged entries and
 729          * proceed to check the next entries if no match was found
 730          */
 731         for (i = 0; i < resync_async->loglen; i++)
 732                 if (req_seq == resync_async->log[i] &&
 733                     atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) {
 734                         *rcd_delta = resync_async->rcd_delta - i;
 735                         *seq = req_seq;
 736                         resync_async->loglen = 0;
 737                         resync_async->rcd_delta = 0;
 738                         return true;
 739                 }
 740
 741         resync_async->loglen = 0;
 742         resync_async->rcd_delta = 0;
 743
 744         if (req_seq == *seq &&
 745             atomic64_try_cmpxchg(&resync_async->req,
 746                                  &resync_req, 0))
 747                 return true;
 748
 749         return false;
 750 }
 751
 752 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
 753 {
 754         struct tls_context *tls_ctx = tls_get_ctx(sk);
 755         struct tls_offload_context_rx *rx_ctx;
 756         u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 757         u32 sock_data, is_req_pending;
 758         struct tls_prot_info *prot;
 759         s64 resync_req;
 760         u16 rcd_delta;
 761         u32 req_seq;
 762
 763         if (tls_ctx->rx_conf != TLS_HW)
 764                 return;
 765         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags)))
 766                 return;
 767
 768         prot = &tls_ctx->prot_info;
 769         rx_ctx = tls_offload_ctx_rx(tls_ctx);
 770         memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 771
 772         switch (rx_ctx->resync_type) {
 773         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
 774                 resync_req = atomic64_read(&rx_ctx->resync_req);
 775                 req_seq = resync_req >> 32;
 776                 seq += TLS_HEADER_SIZE - 1;
 777                 is_req_pending = resync_req;
 778
 779                 if (likely(!is_req_pending) || req_seq != seq ||
 780                     !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
 781                         return;
 782                 break;
 783         case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
 784                 if (likely(!rx_ctx->resync_nh_do_now))
 785                         return;
 786
 787                 /* head of next rec is already in, note that the sock_inq will
 788                  * include the currently parsed message when called from parser
 789                  */
 790                 sock_data = tcp_inq(sk);
 791                 if (sock_data > rcd_len) {
 792                         trace_tls_device_rx_resync_nh_delay(sk, sock_data,
 793                                                             rcd_len);
 794                         return;
 795                 }
 796
 797                 rx_ctx->resync_nh_do_now = 0;
 798                 seq += rcd_len;
 799                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 800                 break;
 801         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
 802                 resync_req = atomic64_read(&rx_ctx->resync_async->req);
 803                 is_req_pending = resync_req;
 804                 if (likely(!is_req_pending))
 805                         return;
 806
 807                 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
 808                                                 resync_req, &seq, &rcd_delta))
 809                         return;
 810                 tls_bigint_subtract(rcd_sn, rcd_delta);
 811                 break;
 812         }
 813
 814         tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
 815 }
 816
 817 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
 818                                            struct tls_offload_context_rx *ctx,
 819                                            struct sock *sk, struct sk_buff *skb)
 820 {
 821         struct strp_msg *rxm;
 822
 823         /* device will request resyncs by itself based on stream scan */
 824         if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
 825                 return;
 826         /* already scheduled */
 827         if (ctx->resync_nh_do_now)
 828                 return;
 829         /* seen decrypted fragments since last fully-failed record */
 830         if (ctx->resync_nh_reset) {
 831                 ctx->resync_nh_reset = 0;
 832                 ctx->resync_nh.decrypted_failed = 1;
 833                 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
 834                 return;
 835         }
 836
 837         if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
 838                 return;
 839
 840         /* doing resync, bump the next target in case it fails */
 841         if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
 842                 ctx->resync_nh.decrypted_tgt *= 2;
 843         else
 844                 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
 845
 846         rxm = strp_msg(skb);
 847
 848         /* head of next rec is already in, parser will sync for us */
 849         if (tcp_inq(sk) > rxm->full_len) {
 850                 trace_tls_device_rx_resync_nh_schedule(sk);
 851                 ctx->resync_nh_do_now = 1;
 852         } else {
 853                 struct tls_prot_info *prot = &tls_ctx->prot_info;
 854                 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 855
 856                 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 857                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 858
 859                 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
 860                                      rcd_sn);
 861         }
 862 }
 863
 864 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
 865 {
 866         struct strp_msg *rxm = strp_msg(skb);
 867         int err = 0, offset = rxm->offset, copy, nsg, data_len, pos;
 868         struct sk_buff *skb_iter, *unused;
 869         struct scatterlist sg[1];
 870         char *orig_buf, *buf;
 871
 872         orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE +
 873                            TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation);
 874         if (!orig_buf)
 875                 return -ENOMEM;
 876         buf = orig_buf;
 877
 878         nsg = skb_cow_data(skb, 0, &unused);
 879         if (unlikely(nsg < 0)) {
 880                 err = nsg;
 881                 goto free_buf;
 882         }
 883
 884         sg_init_table(sg, 1);
 885         sg_set_buf(&sg[0], buf,
 886                    rxm->full_len + TLS_HEADER_SIZE +
 887                    TLS_CIPHER_AES_GCM_128_IV_SIZE);
 888         err = skb_copy_bits(skb, offset, buf,
 889                             TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
 890         if (err)
 891                 goto free_buf;
 892
 893         /* We are interested only in the decrypted data not the auth */
 894         err = decrypt_skb(sk, skb, sg);
 895         if (err != -EBADMSG)
 896                 goto free_buf;
 897         else
 898                 err = 0;
 899
 900         data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE;
 901
 902         if (skb_pagelen(skb) > offset) {
 903                 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 904
 905                 if (skb->decrypted) {
 906                         err = skb_store_bits(skb, offset, buf, copy);
 907                         if (err)
 908                                 goto free_buf;
 909                 }
 910
 911                 offset += copy;
 912                 buf += copy;
 913         }
 914
 915         pos = skb_pagelen(skb);
 916         skb_walk_frags(skb, skb_iter) {
 917                 int frag_pos;
 918
 919                 /* Practically all frags must belong to msg if reencrypt
 920                  * is needed with current strparser and coalescing logic,
 921                  * but strparser may "get optimized", so let's be safe.
 922                  */
 923                 if (pos + skb_iter->len <= offset)
 924                         goto done_with_frag;
 925                 if (pos >= data_len + rxm->offset)
 926                         break;
 927
 928                 frag_pos = offset - pos;
 929                 copy = min_t(int, skb_iter->len - frag_pos,
 930                              data_len + rxm->offset - offset);
 931
 932                 if (skb_iter->decrypted) {
 933                         err = skb_store_bits(skb_iter, frag_pos, buf, copy);
 934                         if (err)
 935                                 goto free_buf;
 936                 }
 937
 938                 offset += copy;
 939                 buf += copy;
 940 done_with_frag:
 941                 pos += skb_iter->len;
 942         }
 943
 944 free_buf:
 945         kfree(orig_buf);
 946         return err;
 947 }
 948
 949 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx,
 950                          struct sk_buff *skb, struct strp_msg *rxm)
 951 {
 952         struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
 953         int is_decrypted = skb->decrypted;
 954         int is_encrypted = !is_decrypted;
 955         struct sk_buff *skb_iter;
 956
 957         /* Check if all the data is decrypted already */
 958         skb_walk_frags(skb, skb_iter) {
 959                 is_decrypted &= skb_iter->decrypted;
 960                 is_encrypted &= !skb_iter->decrypted;
 961         }
 962
 963         trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
 964                                    tls_ctx->rx.rec_seq, rxm->full_len,
 965                                    is_encrypted, is_decrypted);
 966
 967         ctx->sw.decrypted |= is_decrypted;
 968
 969         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) {
 970                 if (likely(is_encrypted || is_decrypted))
 971                         return 0;
 972
 973                 /* After tls_device_down disables the offload, the next SKB will
 974                  * likely have initial fragments decrypted, and final ones not
 975                  * decrypted. We need to reencrypt that single SKB.
 976                  */
 977                 return tls_device_reencrypt(sk, skb);
 978         }
 979
 980         /* Return immediately if the record is either entirely plaintext or
 981          * entirely ciphertext. Otherwise handle reencrypt partially decrypted
 982          * record.
 983          */
 984         if (is_decrypted) {
 985                 ctx->resync_nh_reset = 1;
 986                 return 0;
 987         }
 988         if (is_encrypted) {
 989                 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
 990                 return 0;
 991         }
 992
 993         ctx->resync_nh_reset = 1;
 994         return tls_device_reencrypt(sk, skb);
 995 }
 996
 997 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
 998                               struct net_device *netdev)
 999 {
1000         if (sk->sk_destruct != tls_device_sk_destruct) {
1001                 refcount_set(&ctx->refcount, 1);
1002                 dev_hold(netdev);
1003                 ctx->netdev = netdev;
1004                 spin_lock_irq(&tls_device_lock);
1005                 list_add_tail(&ctx->list, &tls_device_list);
1006                 spin_unlock_irq(&tls_device_lock);
1007
1008                 ctx->sk_destruct = sk->sk_destruct;
1009                 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
1010         }
1011 }
1012
1013 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
1014 {
1015         u16 nonce_size, tag_size, iv_size, rec_seq_size, salt_size;
1016         struct tls_context *tls_ctx = tls_get_ctx(sk);
1017         struct tls_prot_info *prot = &tls_ctx->prot_info;
1018         struct tls_record_info *start_marker_record;
1019         struct tls_offload_context_tx *offload_ctx;
1020         struct tls_crypto_info *crypto_info;
1021         struct net_device *netdev;
1022         char *iv, *rec_seq;
1023         struct sk_buff *skb;
1024         __be64 rcd_sn;
1025         int rc;
1026
1027         if (!ctx)
1028                 return -EINVAL;
1029
1030         if (ctx->priv_ctx_tx)
1031                 return -EEXIST;
1032
1033         start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1034         if (!start_marker_record)
1035                 return -ENOMEM;
1036
1037         offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
1038         if (!offload_ctx) {
1039                 rc = -ENOMEM;
1040                 goto free_marker_record;
1041         }
1042
1043         crypto_info = &ctx->crypto_send.info;
1044         if (crypto_info->version != TLS_1_2_VERSION) {
1045                 rc = -EOPNOTSUPP;
1046                 goto free_offload_ctx;
1047         }
1048
1049         switch (crypto_info->cipher_type) {
1050         case TLS_CIPHER_AES_GCM_128:
1051                 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1052                 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
1053                 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1054                 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
1055                 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
1056                 salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
1057                 rec_seq =
1058                  ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
1059                 break;
1060         default:
1061                 rc = -EINVAL;
1062                 goto free_offload_ctx;
1063         }
1064
1065         /* Sanity-check the rec_seq_size for stack allocations */
1066         if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
1067                 rc = -EINVAL;
1068                 goto free_offload_ctx;
1069         }
1070
1071         prot->version = crypto_info->version;
1072         prot->cipher_type = crypto_info->cipher_type;
1073         prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
1074         prot->tag_size = tag_size;
1075         prot->overhead_size = prot->prepend_size + prot->tag_size;
1076         prot->iv_size = iv_size;
1077         prot->salt_size = salt_size;
1078         ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
1079                              GFP_KERNEL);
1080         if (!ctx->tx.iv) {
1081                 rc = -ENOMEM;
1082                 goto free_offload_ctx;
1083         }
1084
1085         memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
1086
1087         prot->rec_seq_size = rec_seq_size;
1088         ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
1089         if (!ctx->tx.rec_seq) {
1090                 rc = -ENOMEM;
1091                 goto free_iv;
1092         }
1093
1094         rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1095         if (rc)
1096                 goto free_rec_seq;
1097
1098         /* start at rec_seq - 1 to account for the start marker record */
1099         memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1100         offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1101
1102         start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1103         start_marker_record->len = 0;
1104         start_marker_record->num_frags = 0;
1105
1106         INIT_LIST_HEAD(&offload_ctx->records_list);
1107         list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1108         spin_lock_init(&offload_ctx->lock);
1109         sg_init_table(offload_ctx->sg_tx_data,
1110                       ARRAY_SIZE(offload_ctx->sg_tx_data));
1111
1112         clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1113         ctx->push_pending_record = tls_device_push_pending_record;
1114
1115         /* TLS offload is greatly simplified if we don't send
1116          * SKBs where only part of the payload needs to be encrypted.
1117          * So mark the last skb in the write queue as end of record.
1118          */
1119         skb = tcp_write_queue_tail(sk);
1120         if (skb)
1121                 TCP_SKB_CB(skb)->eor = 1;
1122
1123         netdev = get_netdev_for_sock(sk);
1124         if (!netdev) {
1125                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1126                 rc = -EINVAL;
1127                 goto disable_cad;
1128         }
1129
1130         if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1131                 rc = -EOPNOTSUPP;
1132                 goto release_netdev;
1133         }
1134
1135         /* Avoid offloading if the device is down
1136          * We don't want to offload new flows after
1137          * the NETDEV_DOWN event
1138          *
1139          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1140          * handler thus protecting from the device going down before
1141          * ctx was added to tls_device_list.
1142          */
1143         down_read(&device_offload_lock);
1144         if (!(netdev->flags & IFF_UP)) {
1145                 rc = -EINVAL;
1146                 goto release_lock;
1147         }
1148
1149         ctx->priv_ctx_tx = offload_ctx;
1150         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1151                                              &ctx->crypto_send.info,
1152                                              tcp_sk(sk)->write_seq);
1153         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1154                                      tcp_sk(sk)->write_seq, rec_seq, rc);
1155         if (rc)
1156                 goto release_lock;
1157
1158         tls_device_attach(ctx, sk, netdev);
1159         up_read(&device_offload_lock);
1160
1161         /* following this assignment tls_is_sk_tx_device_offloaded
1162          * will return true and the context might be accessed
1163          * by the netdev's xmit function.
1164          */
1165         smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1166         dev_put(netdev);
1167
1168         return 0;
1169
1170 release_lock:
1171         up_read(&device_offload_lock);
1172 release_netdev:
1173         dev_put(netdev);
1174 disable_cad:
1175         clean_acked_data_disable(inet_csk(sk));
1176         crypto_free_aead(offload_ctx->aead_send);
1177 free_rec_seq:
1178         kfree(ctx->tx.rec_seq);
1179 free_iv:
1180         kfree(ctx->tx.iv);
1181 free_offload_ctx:
1182         kfree(offload_ctx);
1183         ctx->priv_ctx_tx = NULL;
1184 free_marker_record:
1185         kfree(start_marker_record);
1186         return rc;
1187 }
1188
1189 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1190 {
1191         struct tls12_crypto_info_aes_gcm_128 *info;
1192         struct tls_offload_context_rx *context;
1193         struct net_device *netdev;
1194         int rc = 0;
1195
1196         if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1197                 return -EOPNOTSUPP;
1198
1199         netdev = get_netdev_for_sock(sk);
1200         if (!netdev) {
1201                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1202                 return -EINVAL;
1203         }
1204
1205         if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1206                 rc = -EOPNOTSUPP;
1207                 goto release_netdev;
1208         }
1209
1210         /* Avoid offloading if the device is down
1211          * We don't want to offload new flows after
1212          * the NETDEV_DOWN event
1213          *
1214          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1215          * handler thus protecting from the device going down before
1216          * ctx was added to tls_device_list.
1217          */
1218         down_read(&device_offload_lock);
1219         if (!(netdev->flags & IFF_UP)) {
1220                 rc = -EINVAL;
1221                 goto release_lock;
1222         }
1223
1224         context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1225         if (!context) {
1226                 rc = -ENOMEM;
1227                 goto release_lock;
1228         }
1229         context->resync_nh_reset = 1;
1230
1231         ctx->priv_ctx_rx = context;
1232         rc = tls_set_sw_offload(sk, ctx, 0);
1233         if (rc)
1234                 goto release_ctx;
1235
1236         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1237                                              &ctx->crypto_recv.info,
1238                                              tcp_sk(sk)->copied_seq);
1239         info = (void *)&ctx->crypto_recv.info;
1240         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1241                                      tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1242         if (rc)
1243                 goto free_sw_resources;
1244
1245         tls_device_attach(ctx, sk, netdev);
1246         up_read(&device_offload_lock);
1247
1248         dev_put(netdev);
1249
1250         return 0;
1251
1252 free_sw_resources:
1253         up_read(&device_offload_lock);
1254         tls_sw_free_resources_rx(sk);
1255         down_read(&device_offload_lock);
1256 release_ctx:
1257         ctx->priv_ctx_rx = NULL;
1258 release_lock:
1259         up_read(&device_offload_lock);
1260 release_netdev:
1261         dev_put(netdev);
1262         return rc;
1263 }
1264
1265 void tls_device_offload_cleanup_rx(struct sock *sk)
1266 {
1267         struct tls_context *tls_ctx = tls_get_ctx(sk);
1268         struct net_device *netdev;
1269
1270         down_read(&device_offload_lock);
1271         netdev = tls_ctx->netdev;
1272         if (!netdev)
1273                 goto out;
1274
1275         netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1276                                         TLS_OFFLOAD_CTX_DIR_RX);
1277
1278         if (tls_ctx->tx_conf != TLS_HW) {
1279                 dev_put(netdev);
1280                 tls_ctx->netdev = NULL;
1281         } else {
1282                 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
1283         }
1284 out:
1285         up_read(&device_offload_lock);
1286         tls_sw_release_resources_rx(sk);
1287 }
1288
1289 static int tls_device_down(struct net_device *netdev)
1290 {
1291         struct tls_context *ctx, *tmp;
1292         unsigned long flags;
1293         LIST_HEAD(list);
1294
1295         /* Request a write lock to block new offload attempts */
1296         down_write(&device_offload_lock);
1297
1298         spin_lock_irqsave(&tls_device_lock, flags);
1299         list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1300                 if (ctx->netdev != netdev ||
1301                     !refcount_inc_not_zero(&ctx->refcount))
1302                         continue;
1303
1304                 list_move(&ctx->list, &list);
1305         }
1306         spin_unlock_irqrestore(&tls_device_lock, flags);
1307
1308         list_for_each_entry_safe(ctx, tmp, &list, list) {
1309                 /* Stop offloaded TX and switch to the fallback.
1310                  * tls_is_sk_tx_device_offloaded will return false.
1311                  */
1312                 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw);
1313
1314                 /* Stop the RX and TX resync.
1315                  * tls_dev_resync must not be called after tls_dev_del.
1316                  */
1317                 WRITE_ONCE(ctx->netdev, NULL);
1318
1319                 /* Start skipping the RX resync logic completely. */
1320                 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags);
1321
1322                 /* Sync with inflight packets. After this point:
1323                  * TX: no non-encrypted packets will be passed to the driver.
1324                  * RX: resync requests from the driver will be ignored.
1325                  */
1326                 synchronize_net();
1327
1328                 /* Release the offload context on the driver side. */
1329                 if (ctx->tx_conf == TLS_HW)
1330                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1331                                                         TLS_OFFLOAD_CTX_DIR_TX);
1332                 if (ctx->rx_conf == TLS_HW &&
1333                     !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags))
1334                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1335                                                         TLS_OFFLOAD_CTX_DIR_RX);
1336
1337                 dev_put(netdev);
1338
1339                 /* Move the context to a separate list for two reasons:
1340                  * 1. When the context is deallocated, list_del is called.
1341                  * 2. It's no longer an offloaded context, so we don't want to
1342                  *    run offload-specific code on this context.
1343                  */
1344                 spin_lock_irqsave(&tls_device_lock, flags);
1345                 list_move_tail(&ctx->list, &tls_device_down_list);
1346                 spin_unlock_irqrestore(&tls_device_lock, flags);
1347
1348                 /* Device contexts for RX and TX will be freed in on sk_destruct
1349                  * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW.
1350                  * Now release the ref taken above.
1351                  */
1352                 if (refcount_dec_and_test(&ctx->refcount))
1353                         tls_device_free_ctx(ctx);
1354         }
1355
1356         up_write(&device_offload_lock);
1357
1358         flush_work(&tls_device_gc_work);
1359
1360         return NOTIFY_DONE;
1361 }
1362
1363 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1364                          void *ptr)
1365 {
1366         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1367
1368         if (!dev->tlsdev_ops &&
1369             !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1370                 return NOTIFY_DONE;
1371
1372         switch (event) {
1373         case NETDEV_REGISTER:
1374         case NETDEV_FEAT_CHANGE:
1375                 if (netif_is_bond_master(dev))
1376                         return NOTIFY_DONE;
1377                 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1378                     !dev->tlsdev_ops->tls_dev_resync)
1379                         return NOTIFY_BAD;
1380
1381                 if  (dev->tlsdev_ops &&
1382                      dev->tlsdev_ops->tls_dev_add &&
1383                      dev->tlsdev_ops->tls_dev_del)
1384                         return NOTIFY_DONE;
1385                 else
1386                         return NOTIFY_BAD;
1387         case NETDEV_DOWN:
1388                 return tls_device_down(dev);
1389         }
1390         return NOTIFY_DONE;
1391 }
1392
1393 static struct notifier_block tls_dev_notifier = {
1394         .notifier_call  = tls_dev_event,
1395 };
1396
1397 void __init tls_device_init(void)
1398 {
1399         register_netdevice_notifier(&tls_dev_notifier);
1400 }
1401
1402 void __exit tls_device_cleanup(void)
1403 {
1404         unregister_netdevice_notifier(&tls_dev_notifier);
1405         flush_work(&tls_device_gc_work);
1406         clean_acked_data_flush();
1407 }