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 "tls.h"
  42 #include "trace.h"
  43
  44 /* device_offload_lock is used to synchronize tls_dev_add
  45  * against NETDEV_DOWN notifications.
  46  */
  47 static DECLARE_RWSEM(device_offload_lock);
  48
  49 static struct workqueue_struct *destruct_wq __read_mostly;
  50
  51 static LIST_HEAD(tls_device_list);
  52 static LIST_HEAD(tls_device_down_list);
  53 static DEFINE_SPINLOCK(tls_device_lock);
  54
  55 static struct page *dummy_page;
  56
  57 static void tls_device_free_ctx(struct tls_context *ctx)
  58 {
  59         if (ctx->tx_conf == TLS_HW)
  60                 kfree(tls_offload_ctx_tx(ctx));
  61
  62         if (ctx->rx_conf == TLS_HW)
  63                 kfree(tls_offload_ctx_rx(ctx));
  64
  65         tls_ctx_free(NULL, ctx);
  66 }
  67
  68 static void tls_device_tx_del_task(struct work_struct *work)
  69 {
  70         struct tls_offload_context_tx *offload_ctx =
  71                 container_of(work, struct tls_offload_context_tx, destruct_work);
  72         struct tls_context *ctx = offload_ctx->ctx;
  73         struct net_device *netdev;
  74
  75         /* Safe, because this is the destroy flow, refcount is 0, so
  76          * tls_device_down can't store this field in parallel.
  77          */
  78         netdev = rcu_dereference_protected(ctx->netdev,
  79                                            !refcount_read(&ctx->refcount));
  80
  81         netdev->tlsdev_ops->tls_dev_del(netdev, ctx, TLS_OFFLOAD_CTX_DIR_TX);
  82         dev_put(netdev);
  83         ctx->netdev = NULL;
  84         tls_device_free_ctx(ctx);
  85 }
  86
  87 static void tls_device_queue_ctx_destruction(struct tls_context *ctx)
  88 {
  89         struct net_device *netdev;
  90         unsigned long flags;
  91         bool async_cleanup;
  92
  93         spin_lock_irqsave(&tls_device_lock, flags);
  94         if (unlikely(!refcount_dec_and_test(&ctx->refcount))) {
  95                 spin_unlock_irqrestore(&tls_device_lock, flags);
  96                 return;
  97         }
  98
  99         list_del(&ctx->list); /* Remove from tls_device_list / tls_device_down_list */
 100
 101         /* Safe, because this is the destroy flow, refcount is 0, so
 102          * tls_device_down can't store this field in parallel.
 103          */
 104         netdev = rcu_dereference_protected(ctx->netdev,
 105                                            !refcount_read(&ctx->refcount));
 106
 107         async_cleanup = netdev && ctx->tx_conf == TLS_HW;
 108         if (async_cleanup) {
 109                 struct tls_offload_context_tx *offload_ctx = tls_offload_ctx_tx(ctx);
 110
 111                 /* queue_work inside the spinlock
 112                  * to make sure tls_device_down waits for that work.
 113                  */
 114                 queue_work(destruct_wq, &offload_ctx->destruct_work);
 115         }
 116         spin_unlock_irqrestore(&tls_device_lock, flags);
 117
 118         if (!async_cleanup)
 119                 tls_device_free_ctx(ctx);
 120 }
 121
 122 /* We assume that the socket is already connected */
 123 static struct net_device *get_netdev_for_sock(struct sock *sk)
 124 {
 125         struct dst_entry *dst = sk_dst_get(sk);
 126         struct net_device *netdev = NULL;
 127
 128         if (likely(dst)) {
 129                 netdev = netdev_sk_get_lowest_dev(dst->dev, sk);
 130                 dev_hold(netdev);
 131         }
 132
 133         dst_release(dst);
 134
 135         return netdev;
 136 }
 137
 138 static void destroy_record(struct tls_record_info *record)
 139 {
 140         int i;
 141
 142         for (i = 0; i < record->num_frags; i++)
 143                 __skb_frag_unref(&record->frags[i], false);
 144         kfree(record);
 145 }
 146
 147 static void delete_all_records(struct tls_offload_context_tx *offload_ctx)
 148 {
 149         struct tls_record_info *info, *temp;
 150
 151         list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) {
 152                 list_del(&info->list);
 153                 destroy_record(info);
 154         }
 155
 156         offload_ctx->retransmit_hint = NULL;
 157 }
 158
 159 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq)
 160 {
 161         struct tls_context *tls_ctx = tls_get_ctx(sk);
 162         struct tls_record_info *info, *temp;
 163         struct tls_offload_context_tx *ctx;
 164         u64 deleted_records = 0;
 165         unsigned long flags;
 166
 167         if (!tls_ctx)
 168                 return;
 169
 170         ctx = tls_offload_ctx_tx(tls_ctx);
 171
 172         spin_lock_irqsave(&ctx->lock, flags);
 173         info = ctx->retransmit_hint;
 174         if (info && !before(acked_seq, info->end_seq))
 175                 ctx->retransmit_hint = NULL;
 176
 177         list_for_each_entry_safe(info, temp, &ctx->records_list, list) {
 178                 if (before(acked_seq, info->end_seq))
 179                         break;
 180                 list_del(&info->list);
 181
 182                 destroy_record(info);
 183                 deleted_records++;
 184         }
 185
 186         ctx->unacked_record_sn += deleted_records;
 187         spin_unlock_irqrestore(&ctx->lock, flags);
 188 }
 189
 190 /* At this point, there should be no references on this
 191  * socket and no in-flight SKBs associated with this
 192  * socket, so it is safe to free all the resources.
 193  */
 194 void tls_device_sk_destruct(struct sock *sk)
 195 {
 196         struct tls_context *tls_ctx = tls_get_ctx(sk);
 197         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 198
 199         tls_ctx->sk_destruct(sk);
 200
 201         if (tls_ctx->tx_conf == TLS_HW) {
 202                 if (ctx->open_record)
 203                         destroy_record(ctx->open_record);
 204                 delete_all_records(ctx);
 205                 crypto_free_aead(ctx->aead_send);
 206                 clean_acked_data_disable(inet_csk(sk));
 207         }
 208
 209         tls_device_queue_ctx_destruction(tls_ctx);
 210 }
 211 EXPORT_SYMBOL_GPL(tls_device_sk_destruct);
 212
 213 void tls_device_free_resources_tx(struct sock *sk)
 214 {
 215         struct tls_context *tls_ctx = tls_get_ctx(sk);
 216
 217         tls_free_partial_record(sk, tls_ctx);
 218 }
 219
 220 void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq)
 221 {
 222         struct tls_context *tls_ctx = tls_get_ctx(sk);
 223
 224         trace_tls_device_tx_resync_req(sk, got_seq, exp_seq);
 225         WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags));
 226 }
 227 EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request);
 228
 229 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
 230                                  u32 seq)
 231 {
 232         struct net_device *netdev;
 233         struct sk_buff *skb;
 234         int err = 0;
 235         u8 *rcd_sn;
 236
 237         skb = tcp_write_queue_tail(sk);
 238         if (skb)
 239                 TCP_SKB_CB(skb)->eor = 1;
 240
 241         rcd_sn = tls_ctx->tx.rec_seq;
 242
 243         trace_tls_device_tx_resync_send(sk, seq, rcd_sn);
 244         down_read(&device_offload_lock);
 245         netdev = rcu_dereference_protected(tls_ctx->netdev,
 246                                            lockdep_is_held(&device_offload_lock));
 247         if (netdev)
 248                 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq,
 249                                                          rcd_sn,
 250                                                          TLS_OFFLOAD_CTX_DIR_TX);
 251         up_read(&device_offload_lock);
 252         if (err)
 253                 return;
 254
 255         clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
 256 }
 257
 258 static void tls_append_frag(struct tls_record_info *record,
 259                             struct page_frag *pfrag,
 260                             int size)
 261 {
 262         skb_frag_t *frag;
 263
 264         frag = &record->frags[record->num_frags - 1];
 265         if (skb_frag_page(frag) == pfrag->page &&
 266             skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
 267                 skb_frag_size_add(frag, size);
 268         } else {
 269                 ++frag;
 270                 skb_frag_fill_page_desc(frag, pfrag->page, pfrag->offset,
 271                                         size);
 272                 ++record->num_frags;
 273                 get_page(pfrag->page);
 274         }
 275
 276         pfrag->offset += size;
 277         record->len += size;
 278 }
 279
 280 static int tls_push_record(struct sock *sk,
 281                            struct tls_context *ctx,
 282                            struct tls_offload_context_tx *offload_ctx,
 283                            struct tls_record_info *record,
 284                            int flags)
 285 {
 286         struct tls_prot_info *prot = &ctx->prot_info;
 287         struct tcp_sock *tp = tcp_sk(sk);
 288         skb_frag_t *frag;
 289         int i;
 290
 291         record->end_seq = tp->write_seq + record->len;
 292         list_add_tail_rcu(&record->list, &offload_ctx->records_list);
 293         offload_ctx->open_record = NULL;
 294
 295         if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
 296                 tls_device_resync_tx(sk, ctx, tp->write_seq);
 297
 298         tls_advance_record_sn(sk, prot, &ctx->tx);
 299
 300         for (i = 0; i < record->num_frags; i++) {
 301                 frag = &record->frags[i];
 302                 sg_unmark_end(&offload_ctx->sg_tx_data[i]);
 303                 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
 304                             skb_frag_size(frag), skb_frag_off(frag));
 305                 sk_mem_charge(sk, skb_frag_size(frag));
 306                 get_page(skb_frag_page(frag));
 307         }
 308         sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
 309
 310         /* all ready, send */
 311         return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
 312 }
 313
 314 static void tls_device_record_close(struct sock *sk,
 315                                     struct tls_context *ctx,
 316                                     struct tls_record_info *record,
 317                                     struct page_frag *pfrag,
 318                                     unsigned char record_type)
 319 {
 320         struct tls_prot_info *prot = &ctx->prot_info;
 321         struct page_frag dummy_tag_frag;
 322
 323         /* append tag
 324          * device will fill in the tag, we just need to append a placeholder
 325          * use socket memory to improve coalescing (re-using a single buffer
 326          * increases frag count)
 327          * if we can't allocate memory now use the dummy page
 328          */
 329         if (unlikely(pfrag->size - pfrag->offset < prot->tag_size) &&
 330             !skb_page_frag_refill(prot->tag_size, pfrag, sk->sk_allocation)) {
 331                 dummy_tag_frag.page = dummy_page;
 332                 dummy_tag_frag.offset = 0;
 333                 pfrag = &dummy_tag_frag;
 334         }
 335         tls_append_frag(record, pfrag, prot->tag_size);
 336
 337         /* fill prepend */
 338         tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
 339                          record->len - prot->overhead_size,
 340                          record_type);
 341 }
 342
 343 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
 344                                  struct page_frag *pfrag,
 345                                  size_t prepend_size)
 346 {
 347         struct tls_record_info *record;
 348         skb_frag_t *frag;
 349
 350         record = kmalloc(sizeof(*record), GFP_KERNEL);
 351         if (!record)
 352                 return -ENOMEM;
 353
 354         frag = &record->frags[0];
 355         skb_frag_fill_page_desc(frag, pfrag->page, pfrag->offset,
 356                                 prepend_size);
 357
 358         get_page(pfrag->page);
 359         pfrag->offset += prepend_size;
 360
 361         record->num_frags = 1;
 362         record->len = prepend_size;
 363         offload_ctx->open_record = record;
 364         return 0;
 365 }
 366
 367 static int tls_do_allocation(struct sock *sk,
 368                              struct tls_offload_context_tx *offload_ctx,
 369                              struct page_frag *pfrag,
 370                              size_t prepend_size)
 371 {
 372         int ret;
 373
 374         if (!offload_ctx->open_record) {
 375                 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
 376                                                    sk->sk_allocation))) {
 377                         READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
 378                         sk_stream_moderate_sndbuf(sk);
 379                         return -ENOMEM;
 380                 }
 381
 382                 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
 383                 if (ret)
 384                         return ret;
 385
 386                 if (pfrag->size > pfrag->offset)
 387                         return 0;
 388         }
 389
 390         if (!sk_page_frag_refill(sk, pfrag))
 391                 return -ENOMEM;
 392
 393         return 0;
 394 }
 395
 396 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
 397 {
 398         size_t pre_copy, nocache;
 399
 400         pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
 401         if (pre_copy) {
 402                 pre_copy = min(pre_copy, bytes);
 403                 if (copy_from_iter(addr, pre_copy, i) != pre_copy)
 404                         return -EFAULT;
 405                 bytes -= pre_copy;
 406                 addr += pre_copy;
 407         }
 408
 409         nocache = round_down(bytes, SMP_CACHE_BYTES);
 410         if (copy_from_iter_nocache(addr, nocache, i) != nocache)
 411                 return -EFAULT;
 412         bytes -= nocache;
 413         addr += nocache;
 414
 415         if (bytes && copy_from_iter(addr, bytes, i) != bytes)
 416                 return -EFAULT;
 417
 418         return 0;
 419 }
 420
 421 static int tls_push_data(struct sock *sk,
 422                          struct iov_iter *iter,
 423                          size_t size, int flags,
 424                          unsigned char record_type)
 425 {
 426         struct tls_context *tls_ctx = tls_get_ctx(sk);
 427         struct tls_prot_info *prot = &tls_ctx->prot_info;
 428         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 429         struct tls_record_info *record;
 430         int tls_push_record_flags;
 431         struct page_frag *pfrag;
 432         size_t orig_size = size;
 433         u32 max_open_record_len;
 434         bool more = false;
 435         bool done = false;
 436         int copy, rc = 0;
 437         long timeo;
 438
 439         if (flags &
 440             ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
 441               MSG_SPLICE_PAGES | MSG_EOR))
 442                 return -EOPNOTSUPP;
 443
 444         if ((flags & (MSG_MORE | MSG_EOR)) == (MSG_MORE | MSG_EOR))
 445                 return -EINVAL;
 446
 447         if (unlikely(sk->sk_err))
 448                 return -sk->sk_err;
 449
 450         flags |= MSG_SENDPAGE_DECRYPTED;
 451         tls_push_record_flags = flags | MSG_MORE;
 452
 453         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
 454         if (tls_is_partially_sent_record(tls_ctx)) {
 455                 rc = tls_push_partial_record(sk, tls_ctx, flags);
 456                 if (rc < 0)
 457                         return rc;
 458         }
 459
 460         pfrag = sk_page_frag(sk);
 461
 462         /* TLS_HEADER_SIZE is not counted as part of the TLS record, and
 463          * we need to leave room for an authentication tag.
 464          */
 465         max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
 466                               prot->prepend_size;
 467         do {
 468                 rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
 469                 if (unlikely(rc)) {
 470                         rc = sk_stream_wait_memory(sk, &timeo);
 471                         if (!rc)
 472                                 continue;
 473
 474                         record = ctx->open_record;
 475                         if (!record)
 476                                 break;
 477 handle_error:
 478                         if (record_type != TLS_RECORD_TYPE_DATA) {
 479                                 /* avoid sending partial
 480                                  * record with type !=
 481                                  * application_data
 482                                  */
 483                                 size = orig_size;
 484                                 destroy_record(record);
 485                                 ctx->open_record = NULL;
 486                         } else if (record->len > prot->prepend_size) {
 487                                 goto last_record;
 488                         }
 489
 490                         break;
 491                 }
 492
 493                 record = ctx->open_record;
 494
 495                 copy = min_t(size_t, size, max_open_record_len - record->len);
 496                 if (copy && (flags & MSG_SPLICE_PAGES)) {
 497                         struct page_frag zc_pfrag;
 498                         struct page **pages = &zc_pfrag.page;
 499                         size_t off;
 500
 501                         rc = iov_iter_extract_pages(iter, &pages,
 502                                                     copy, 1, 0, &off);
 503                         if (rc <= 0) {
 504                                 if (rc == 0)
 505                                         rc = -EIO;
 506                                 goto handle_error;
 507                         }
 508                         copy = rc;
 509
 510                         if (WARN_ON_ONCE(!sendpage_ok(zc_pfrag.page))) {
 511                                 iov_iter_revert(iter, copy);
 512                                 rc = -EIO;
 513                                 goto handle_error;
 514                         }
 515
 516                         zc_pfrag.offset = off;
 517                         zc_pfrag.size = copy;
 518                         tls_append_frag(record, &zc_pfrag, copy);
 519                 } else if (copy) {
 520                         copy = min_t(size_t, copy, pfrag->size - pfrag->offset);
 521
 522                         rc = tls_device_copy_data(page_address(pfrag->page) +
 523                                                   pfrag->offset, copy,
 524                                                   iter);
 525                         if (rc)
 526                                 goto handle_error;
 527                         tls_append_frag(record, pfrag, copy);
 528                 }
 529
 530                 size -= copy;
 531                 if (!size) {
 532 last_record:
 533                         tls_push_record_flags = flags;
 534                         if (flags & MSG_MORE) {
 535                                 more = true;
 536                                 break;
 537                         }
 538
 539                         done = true;
 540                 }
 541
 542                 if (done || record->len >= max_open_record_len ||
 543                     (record->num_frags >= MAX_SKB_FRAGS - 1)) {
 544                         tls_device_record_close(sk, tls_ctx, record,
 545                                                 pfrag, record_type);
 546
 547                         rc = tls_push_record(sk,
 548                                              tls_ctx,
 549                                              ctx,
 550                                              record,
 551                                              tls_push_record_flags);
 552                         if (rc < 0)
 553                                 break;
 554                 }
 555         } while (!done);
 556
 557         tls_ctx->pending_open_record_frags = more;
 558
 559         if (orig_size - size > 0)
 560                 rc = orig_size - size;
 561
 562         return rc;
 563 }
 564
 565 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 566 {
 567         unsigned char record_type = TLS_RECORD_TYPE_DATA;
 568         struct tls_context *tls_ctx = tls_get_ctx(sk);
 569         int rc;
 570
 571         if (!tls_ctx->zerocopy_sendfile)
 572                 msg->msg_flags &= ~MSG_SPLICE_PAGES;
 573
 574         mutex_lock(&tls_ctx->tx_lock);
 575         lock_sock(sk);
 576
 577         if (unlikely(msg->msg_controllen)) {
 578                 rc = tls_process_cmsg(sk, msg, &record_type);
 579                 if (rc)
 580                         goto out;
 581         }
 582
 583         rc = tls_push_data(sk, &msg->msg_iter, size, msg->msg_flags,
 584                            record_type);
 585
 586 out:
 587         release_sock(sk);
 588         mutex_unlock(&tls_ctx->tx_lock);
 589         return rc;
 590 }
 591
 592 void tls_device_splice_eof(struct socket *sock)
 593 {
 594         struct sock *sk = sock->sk;
 595         struct tls_context *tls_ctx = tls_get_ctx(sk);
 596         struct iov_iter iter = {};
 597
 598         if (!tls_is_partially_sent_record(tls_ctx))
 599                 return;
 600
 601         mutex_lock(&tls_ctx->tx_lock);
 602         lock_sock(sk);
 603
 604         if (tls_is_partially_sent_record(tls_ctx)) {
 605                 iov_iter_bvec(&iter, ITER_SOURCE, NULL, 0, 0);
 606                 tls_push_data(sk, &iter, 0, 0, TLS_RECORD_TYPE_DATA);
 607         }
 608
 609         release_sock(sk);
 610         mutex_unlock(&tls_ctx->tx_lock);
 611 }
 612
 613 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
 614                                        u32 seq, u64 *p_record_sn)
 615 {
 616         u64 record_sn = context->hint_record_sn;
 617         struct tls_record_info *info, *last;
 618
 619         info = context->retransmit_hint;
 620         if (!info ||
 621             before(seq, info->end_seq - info->len)) {
 622                 /* if retransmit_hint is irrelevant start
 623                  * from the beginning of the list
 624                  */
 625                 info = list_first_entry_or_null(&context->records_list,
 626                                                 struct tls_record_info, list);
 627                 if (!info)
 628                         return NULL;
 629                 /* send the start_marker record if seq number is before the
 630                  * tls offload start marker sequence number. This record is
 631                  * required to handle TCP packets which are before TLS offload
 632                  * started.
 633                  *  And if it's not start marker, look if this seq number
 634                  * belongs to the list.
 635                  */
 636                 if (likely(!tls_record_is_start_marker(info))) {
 637                         /* we have the first record, get the last record to see
 638                          * if this seq number belongs to the list.
 639                          */
 640                         last = list_last_entry(&context->records_list,
 641                                                struct tls_record_info, list);
 642
 643                         if (!between(seq, tls_record_start_seq(info),
 644                                      last->end_seq))
 645                                 return NULL;
 646                 }
 647                 record_sn = context->unacked_record_sn;
 648         }
 649
 650         /* We just need the _rcu for the READ_ONCE() */
 651         rcu_read_lock();
 652         list_for_each_entry_from_rcu(info, &context->records_list, list) {
 653                 if (before(seq, info->end_seq)) {
 654                         if (!context->retransmit_hint ||
 655                             after(info->end_seq,
 656                                   context->retransmit_hint->end_seq)) {
 657                                 context->hint_record_sn = record_sn;
 658                                 context->retransmit_hint = info;
 659                         }
 660                         *p_record_sn = record_sn;
 661                         goto exit_rcu_unlock;
 662                 }
 663                 record_sn++;
 664         }
 665         info = NULL;
 666
 667 exit_rcu_unlock:
 668         rcu_read_unlock();
 669         return info;
 670 }
 671 EXPORT_SYMBOL(tls_get_record);
 672
 673 static int tls_device_push_pending_record(struct sock *sk, int flags)
 674 {
 675         struct iov_iter iter;
 676
 677         iov_iter_kvec(&iter, ITER_SOURCE, NULL, 0, 0);
 678         return tls_push_data(sk, &iter, 0, flags, TLS_RECORD_TYPE_DATA);
 679 }
 680
 681 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 682 {
 683         if (tls_is_partially_sent_record(ctx)) {
 684                 gfp_t sk_allocation = sk->sk_allocation;
 685
 686                 WARN_ON_ONCE(sk->sk_write_pending);
 687
 688                 sk->sk_allocation = GFP_ATOMIC;
 689                 tls_push_partial_record(sk, ctx,
 690                                         MSG_DONTWAIT | MSG_NOSIGNAL |
 691                                         MSG_SENDPAGE_DECRYPTED);
 692                 sk->sk_allocation = sk_allocation;
 693         }
 694 }
 695
 696 static void tls_device_resync_rx(struct tls_context *tls_ctx,
 697                                  struct sock *sk, u32 seq, u8 *rcd_sn)
 698 {
 699         struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
 700         struct net_device *netdev;
 701
 702         trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
 703         rcu_read_lock();
 704         netdev = rcu_dereference(tls_ctx->netdev);
 705         if (netdev)
 706                 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
 707                                                    TLS_OFFLOAD_CTX_DIR_RX);
 708         rcu_read_unlock();
 709         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
 710 }
 711
 712 static bool
 713 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
 714                            s64 resync_req, u32 *seq, u16 *rcd_delta)
 715 {
 716         u32 is_async = resync_req & RESYNC_REQ_ASYNC;
 717         u32 req_seq = resync_req >> 32;
 718         u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
 719         u16 i;
 720
 721         *rcd_delta = 0;
 722
 723         if (is_async) {
 724                 /* shouldn't get to wraparound:
 725                  * too long in async stage, something bad happened
 726                  */
 727                 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
 728                         return false;
 729
 730                 /* asynchronous stage: log all headers seq such that
 731                  * req_seq <= seq <= end_seq, and wait for real resync request
 732                  */
 733                 if (before(*seq, req_seq))
 734                         return false;
 735                 if (!after(*seq, req_end) &&
 736                     resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
 737                         resync_async->log[resync_async->loglen++] = *seq;
 738
 739                 resync_async->rcd_delta++;
 740
 741                 return false;
 742         }
 743
 744         /* synchronous stage: check against the logged entries and
 745          * proceed to check the next entries if no match was found
 746          */
 747         for (i = 0; i < resync_async->loglen; i++)
 748                 if (req_seq == resync_async->log[i] &&
 749                     atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) {
 750                         *rcd_delta = resync_async->rcd_delta - i;
 751                         *seq = req_seq;
 752                         resync_async->loglen = 0;
 753                         resync_async->rcd_delta = 0;
 754                         return true;
 755                 }
 756
 757         resync_async->loglen = 0;
 758         resync_async->rcd_delta = 0;
 759
 760         if (req_seq == *seq &&
 761             atomic64_try_cmpxchg(&resync_async->req,
 762                                  &resync_req, 0))
 763                 return true;
 764
 765         return false;
 766 }
 767
 768 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
 769 {
 770         struct tls_context *tls_ctx = tls_get_ctx(sk);
 771         struct tls_offload_context_rx *rx_ctx;
 772         u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 773         u32 sock_data, is_req_pending;
 774         struct tls_prot_info *prot;
 775         s64 resync_req;
 776         u16 rcd_delta;
 777         u32 req_seq;
 778
 779         if (tls_ctx->rx_conf != TLS_HW)
 780                 return;
 781         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags)))
 782                 return;
 783
 784         prot = &tls_ctx->prot_info;
 785         rx_ctx = tls_offload_ctx_rx(tls_ctx);
 786         memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 787
 788         switch (rx_ctx->resync_type) {
 789         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
 790                 resync_req = atomic64_read(&rx_ctx->resync_req);
 791                 req_seq = resync_req >> 32;
 792                 seq += TLS_HEADER_SIZE - 1;
 793                 is_req_pending = resync_req;
 794
 795                 if (likely(!is_req_pending) || req_seq != seq ||
 796                     !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
 797                         return;
 798                 break;
 799         case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
 800                 if (likely(!rx_ctx->resync_nh_do_now))
 801                         return;
 802
 803                 /* head of next rec is already in, note that the sock_inq will
 804                  * include the currently parsed message when called from parser
 805                  */
 806                 sock_data = tcp_inq(sk);
 807                 if (sock_data > rcd_len) {
 808                         trace_tls_device_rx_resync_nh_delay(sk, sock_data,
 809                                                             rcd_len);
 810                         return;
 811                 }
 812
 813                 rx_ctx->resync_nh_do_now = 0;
 814                 seq += rcd_len;
 815                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 816                 break;
 817         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
 818                 resync_req = atomic64_read(&rx_ctx->resync_async->req);
 819                 is_req_pending = resync_req;
 820                 if (likely(!is_req_pending))
 821                         return;
 822
 823                 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
 824                                                 resync_req, &seq, &rcd_delta))
 825                         return;
 826                 tls_bigint_subtract(rcd_sn, rcd_delta);
 827                 break;
 828         }
 829
 830         tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
 831 }
 832
 833 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
 834                                            struct tls_offload_context_rx *ctx,
 835                                            struct sock *sk, struct sk_buff *skb)
 836 {
 837         struct strp_msg *rxm;
 838
 839         /* device will request resyncs by itself based on stream scan */
 840         if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
 841                 return;
 842         /* already scheduled */
 843         if (ctx->resync_nh_do_now)
 844                 return;
 845         /* seen decrypted fragments since last fully-failed record */
 846         if (ctx->resync_nh_reset) {
 847                 ctx->resync_nh_reset = 0;
 848                 ctx->resync_nh.decrypted_failed = 1;
 849                 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
 850                 return;
 851         }
 852
 853         if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
 854                 return;
 855
 856         /* doing resync, bump the next target in case it fails */
 857         if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
 858                 ctx->resync_nh.decrypted_tgt *= 2;
 859         else
 860                 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
 861
 862         rxm = strp_msg(skb);
 863
 864         /* head of next rec is already in, parser will sync for us */
 865         if (tcp_inq(sk) > rxm->full_len) {
 866                 trace_tls_device_rx_resync_nh_schedule(sk);
 867                 ctx->resync_nh_do_now = 1;
 868         } else {
 869                 struct tls_prot_info *prot = &tls_ctx->prot_info;
 870                 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 871
 872                 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 873                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 874
 875                 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
 876                                      rcd_sn);
 877         }
 878 }
 879
 880 static int
 881 tls_device_reencrypt(struct sock *sk, struct tls_context *tls_ctx)
 882 {
 883         struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
 884         const struct tls_cipher_desc *cipher_desc;
 885         int err, offset, copy, data_len, pos;
 886         struct sk_buff *skb, *skb_iter;
 887         struct scatterlist sg[1];
 888         struct strp_msg *rxm;
 889         char *orig_buf, *buf;
 890
 891         cipher_desc = get_cipher_desc(tls_ctx->crypto_recv.info.cipher_type);
 892         DEBUG_NET_WARN_ON_ONCE(!cipher_desc || !cipher_desc->offloadable);
 893
 894         rxm = strp_msg(tls_strp_msg(sw_ctx));
 895         orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + cipher_desc->iv,
 896                            sk->sk_allocation);
 897         if (!orig_buf)
 898                 return -ENOMEM;
 899         buf = orig_buf;
 900
 901         err = tls_strp_msg_cow(sw_ctx);
 902         if (unlikely(err))
 903                 goto free_buf;
 904
 905         skb = tls_strp_msg(sw_ctx);
 906         rxm = strp_msg(skb);
 907         offset = rxm->offset;
 908
 909         sg_init_table(sg, 1);
 910         sg_set_buf(&sg[0], buf,
 911                    rxm->full_len + TLS_HEADER_SIZE + cipher_desc->iv);
 912         err = skb_copy_bits(skb, offset, buf, TLS_HEADER_SIZE + cipher_desc->iv);
 913         if (err)
 914                 goto free_buf;
 915
 916         /* We are interested only in the decrypted data not the auth */
 917         err = decrypt_skb(sk, sg);
 918         if (err != -EBADMSG)
 919                 goto free_buf;
 920         else
 921                 err = 0;
 922
 923         data_len = rxm->full_len - cipher_desc->tag;
 924
 925         if (skb_pagelen(skb) > offset) {
 926                 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 927
 928                 if (skb->decrypted) {
 929                         err = skb_store_bits(skb, offset, buf, copy);
 930                         if (err)
 931                                 goto free_buf;
 932                 }
 933
 934                 offset += copy;
 935                 buf += copy;
 936         }
 937
 938         pos = skb_pagelen(skb);
 939         skb_walk_frags(skb, skb_iter) {
 940                 int frag_pos;
 941
 942                 /* Practically all frags must belong to msg if reencrypt
 943                  * is needed with current strparser and coalescing logic,
 944                  * but strparser may "get optimized", so let's be safe.
 945                  */
 946                 if (pos + skb_iter->len <= offset)
 947                         goto done_with_frag;
 948                 if (pos >= data_len + rxm->offset)
 949                         break;
 950
 951                 frag_pos = offset - pos;
 952                 copy = min_t(int, skb_iter->len - frag_pos,
 953                              data_len + rxm->offset - offset);
 954
 955                 if (skb_iter->decrypted) {
 956                         err = skb_store_bits(skb_iter, frag_pos, buf, copy);
 957                         if (err)
 958                                 goto free_buf;
 959                 }
 960
 961                 offset += copy;
 962                 buf += copy;
 963 done_with_frag:
 964                 pos += skb_iter->len;
 965         }
 966
 967 free_buf:
 968         kfree(orig_buf);
 969         return err;
 970 }
 971
 972 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx)
 973 {
 974         struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
 975         struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
 976         struct sk_buff *skb = tls_strp_msg(sw_ctx);
 977         struct strp_msg *rxm = strp_msg(skb);
 978         int is_decrypted, is_encrypted;
 979
 980         if (!tls_strp_msg_mixed_decrypted(sw_ctx)) {
 981                 is_decrypted = skb->decrypted;
 982                 is_encrypted = !is_decrypted;
 983         } else {
 984                 is_decrypted = 0;
 985                 is_encrypted = 0;
 986         }
 987
 988         trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
 989                                    tls_ctx->rx.rec_seq, rxm->full_len,
 990                                    is_encrypted, is_decrypted);
 991
 992         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) {
 993                 if (likely(is_encrypted || is_decrypted))
 994                         return is_decrypted;
 995
 996                 /* After tls_device_down disables the offload, the next SKB will
 997                  * likely have initial fragments decrypted, and final ones not
 998                  * decrypted. We need to reencrypt that single SKB.
 999                  */
1000                 return tls_device_reencrypt(sk, tls_ctx);
1001         }
1002
1003         /* Return immediately if the record is either entirely plaintext or
1004          * entirely ciphertext. Otherwise handle reencrypt partially decrypted
1005          * record.
1006          */
1007         if (is_decrypted) {
1008                 ctx->resync_nh_reset = 1;
1009                 return is_decrypted;
1010         }
1011         if (is_encrypted) {
1012                 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
1013                 return 0;
1014         }
1015
1016         ctx->resync_nh_reset = 1;
1017         return tls_device_reencrypt(sk, tls_ctx);
1018 }
1019
1020 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
1021                               struct net_device *netdev)
1022 {
1023         if (sk->sk_destruct != tls_device_sk_destruct) {
1024                 refcount_set(&ctx->refcount, 1);
1025                 dev_hold(netdev);
1026                 RCU_INIT_POINTER(ctx->netdev, netdev);
1027                 spin_lock_irq(&tls_device_lock);
1028                 list_add_tail(&ctx->list, &tls_device_list);
1029                 spin_unlock_irq(&tls_device_lock);
1030
1031                 ctx->sk_destruct = sk->sk_destruct;
1032                 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
1033         }
1034 }
1035
1036 static struct tls_offload_context_tx *alloc_offload_ctx_tx(struct tls_context *ctx)
1037 {
1038         struct tls_offload_context_tx *offload_ctx;
1039         __be64 rcd_sn;
1040
1041         offload_ctx = kzalloc(sizeof(*offload_ctx), GFP_KERNEL);
1042         if (!offload_ctx)
1043                 return NULL;
1044
1045         INIT_WORK(&offload_ctx->destruct_work, tls_device_tx_del_task);
1046         INIT_LIST_HEAD(&offload_ctx->records_list);
1047         spin_lock_init(&offload_ctx->lock);
1048         sg_init_table(offload_ctx->sg_tx_data,
1049                       ARRAY_SIZE(offload_ctx->sg_tx_data));
1050
1051         /* start at rec_seq - 1 to account for the start marker record */
1052         memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1053         offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1054
1055         offload_ctx->ctx = ctx;
1056
1057         return offload_ctx;
1058 }
1059
1060 int tls_set_device_offload(struct sock *sk)
1061 {
1062         struct tls_record_info *start_marker_record;
1063         struct tls_offload_context_tx *offload_ctx;
1064         const struct tls_cipher_desc *cipher_desc;
1065         struct tls_crypto_info *crypto_info;
1066         struct tls_prot_info *prot;
1067         struct net_device *netdev;
1068         struct tls_context *ctx;
1069         struct sk_buff *skb;
1070         char *iv, *rec_seq;
1071         int rc;
1072
1073         ctx = tls_get_ctx(sk);
1074         prot = &ctx->prot_info;
1075
1076         if (ctx->priv_ctx_tx)
1077                 return -EEXIST;
1078
1079         netdev = get_netdev_for_sock(sk);
1080         if (!netdev) {
1081                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1082                 return -EINVAL;
1083         }
1084
1085         if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1086                 rc = -EOPNOTSUPP;
1087                 goto release_netdev;
1088         }
1089
1090         crypto_info = &ctx->crypto_send.info;
1091         if (crypto_info->version != TLS_1_2_VERSION) {
1092                 rc = -EOPNOTSUPP;
1093                 goto release_netdev;
1094         }
1095
1096         cipher_desc = get_cipher_desc(crypto_info->cipher_type);
1097         if (!cipher_desc || !cipher_desc->offloadable) {
1098                 rc = -EINVAL;
1099                 goto release_netdev;
1100         }
1101
1102         rc = init_prot_info(prot, crypto_info, cipher_desc);
1103         if (rc)
1104                 goto release_netdev;
1105
1106         iv = crypto_info_iv(crypto_info, cipher_desc);
1107         rec_seq = crypto_info_rec_seq(crypto_info, cipher_desc);
1108
1109         memcpy(ctx->tx.iv + cipher_desc->salt, iv, cipher_desc->iv);
1110         memcpy(ctx->tx.rec_seq, rec_seq, cipher_desc->rec_seq);
1111
1112         start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1113         if (!start_marker_record) {
1114                 rc = -ENOMEM;
1115                 goto release_netdev;
1116         }
1117
1118         offload_ctx = alloc_offload_ctx_tx(ctx);
1119         if (!offload_ctx) {
1120                 rc = -ENOMEM;
1121                 goto free_marker_record;
1122         }
1123
1124         rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1125         if (rc)
1126                 goto free_offload_ctx;
1127
1128         start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1129         start_marker_record->len = 0;
1130         start_marker_record->num_frags = 0;
1131         list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1132
1133         clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1134         ctx->push_pending_record = tls_device_push_pending_record;
1135
1136         /* TLS offload is greatly simplified if we don't send
1137          * SKBs where only part of the payload needs to be encrypted.
1138          * So mark the last skb in the write queue as end of record.
1139          */
1140         skb = tcp_write_queue_tail(sk);
1141         if (skb)
1142                 TCP_SKB_CB(skb)->eor = 1;
1143
1144         /* Avoid offloading if the device is down
1145          * We don't want to offload new flows after
1146          * the NETDEV_DOWN event
1147          *
1148          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1149          * handler thus protecting from the device going down before
1150          * ctx was added to tls_device_list.
1151          */
1152         down_read(&device_offload_lock);
1153         if (!(netdev->flags & IFF_UP)) {
1154                 rc = -EINVAL;
1155                 goto release_lock;
1156         }
1157
1158         ctx->priv_ctx_tx = offload_ctx;
1159         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1160                                              &ctx->crypto_send.info,
1161                                              tcp_sk(sk)->write_seq);
1162         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1163                                      tcp_sk(sk)->write_seq, rec_seq, rc);
1164         if (rc)
1165                 goto release_lock;
1166
1167         tls_device_attach(ctx, sk, netdev);
1168         up_read(&device_offload_lock);
1169
1170         /* following this assignment tls_is_skb_tx_device_offloaded
1171          * will return true and the context might be accessed
1172          * by the netdev's xmit function.
1173          */
1174         smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1175         dev_put(netdev);
1176
1177         return 0;
1178
1179 release_lock:
1180         up_read(&device_offload_lock);
1181         clean_acked_data_disable(inet_csk(sk));
1182         crypto_free_aead(offload_ctx->aead_send);
1183 free_offload_ctx:
1184         kfree(offload_ctx);
1185         ctx->priv_ctx_tx = NULL;
1186 free_marker_record:
1187         kfree(start_marker_record);
1188 release_netdev:
1189         dev_put(netdev);
1190         return rc;
1191 }
1192
1193 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1194 {
1195         struct tls12_crypto_info_aes_gcm_128 *info;
1196         struct tls_offload_context_rx *context;
1197         struct net_device *netdev;
1198         int rc = 0;
1199
1200         if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1201                 return -EOPNOTSUPP;
1202
1203         netdev = get_netdev_for_sock(sk);
1204         if (!netdev) {
1205                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1206                 return -EINVAL;
1207         }
1208
1209         if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1210                 rc = -EOPNOTSUPP;
1211                 goto release_netdev;
1212         }
1213
1214         /* Avoid offloading if the device is down
1215          * We don't want to offload new flows after
1216          * the NETDEV_DOWN event
1217          *
1218          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1219          * handler thus protecting from the device going down before
1220          * ctx was added to tls_device_list.
1221          */
1222         down_read(&device_offload_lock);
1223         if (!(netdev->flags & IFF_UP)) {
1224                 rc = -EINVAL;
1225                 goto release_lock;
1226         }
1227
1228         context = kzalloc(sizeof(*context), GFP_KERNEL);
1229         if (!context) {
1230                 rc = -ENOMEM;
1231                 goto release_lock;
1232         }
1233         context->resync_nh_reset = 1;
1234
1235         ctx->priv_ctx_rx = context;
1236         rc = tls_set_sw_offload(sk, 0);
1237         if (rc)
1238                 goto release_ctx;
1239
1240         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1241                                              &ctx->crypto_recv.info,
1242                                              tcp_sk(sk)->copied_seq);
1243         info = (void *)&ctx->crypto_recv.info;
1244         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1245                                      tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1246         if (rc)
1247                 goto free_sw_resources;
1248
1249         tls_device_attach(ctx, sk, netdev);
1250         up_read(&device_offload_lock);
1251
1252         dev_put(netdev);
1253
1254         return 0;
1255
1256 free_sw_resources:
1257         up_read(&device_offload_lock);
1258         tls_sw_free_resources_rx(sk);
1259         down_read(&device_offload_lock);
1260 release_ctx:
1261         ctx->priv_ctx_rx = NULL;
1262 release_lock:
1263         up_read(&device_offload_lock);
1264 release_netdev:
1265         dev_put(netdev);
1266         return rc;
1267 }
1268
1269 void tls_device_offload_cleanup_rx(struct sock *sk)
1270 {
1271         struct tls_context *tls_ctx = tls_get_ctx(sk);
1272         struct net_device *netdev;
1273
1274         down_read(&device_offload_lock);
1275         netdev = rcu_dereference_protected(tls_ctx->netdev,
1276                                            lockdep_is_held(&device_offload_lock));
1277         if (!netdev)
1278                 goto out;
1279
1280         netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1281                                         TLS_OFFLOAD_CTX_DIR_RX);
1282
1283         if (tls_ctx->tx_conf != TLS_HW) {
1284                 dev_put(netdev);
1285                 rcu_assign_pointer(tls_ctx->netdev, NULL);
1286         } else {
1287                 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
1288         }
1289 out:
1290         up_read(&device_offload_lock);
1291         tls_sw_release_resources_rx(sk);
1292 }
1293
1294 static int tls_device_down(struct net_device *netdev)
1295 {
1296         struct tls_context *ctx, *tmp;
1297         unsigned long flags;
1298         LIST_HEAD(list);
1299
1300         /* Request a write lock to block new offload attempts */
1301         down_write(&device_offload_lock);
1302
1303         spin_lock_irqsave(&tls_device_lock, flags);
1304         list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1305                 struct net_device *ctx_netdev =
1306                         rcu_dereference_protected(ctx->netdev,
1307                                                   lockdep_is_held(&device_offload_lock));
1308
1309                 if (ctx_netdev != netdev ||
1310                     !refcount_inc_not_zero(&ctx->refcount))
1311                         continue;
1312
1313                 list_move(&ctx->list, &list);
1314         }
1315         spin_unlock_irqrestore(&tls_device_lock, flags);
1316
1317         list_for_each_entry_safe(ctx, tmp, &list, list) {
1318                 /* Stop offloaded TX and switch to the fallback.
1319                  * tls_is_skb_tx_device_offloaded will return false.
1320                  */
1321                 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw);
1322
1323                 /* Stop the RX and TX resync.
1324                  * tls_dev_resync must not be called after tls_dev_del.
1325                  */
1326                 rcu_assign_pointer(ctx->netdev, NULL);
1327
1328                 /* Start skipping the RX resync logic completely. */
1329                 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags);
1330
1331                 /* Sync with inflight packets. After this point:
1332                  * TX: no non-encrypted packets will be passed to the driver.
1333                  * RX: resync requests from the driver will be ignored.
1334                  */
1335                 synchronize_net();
1336
1337                 /* Release the offload context on the driver side. */
1338                 if (ctx->tx_conf == TLS_HW)
1339                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1340                                                         TLS_OFFLOAD_CTX_DIR_TX);
1341                 if (ctx->rx_conf == TLS_HW &&
1342                     !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags))
1343                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1344                                                         TLS_OFFLOAD_CTX_DIR_RX);
1345
1346                 dev_put(netdev);
1347
1348                 /* Move the context to a separate list for two reasons:
1349                  * 1. When the context is deallocated, list_del is called.
1350                  * 2. It's no longer an offloaded context, so we don't want to
1351                  *    run offload-specific code on this context.
1352                  */
1353                 spin_lock_irqsave(&tls_device_lock, flags);
1354                 list_move_tail(&ctx->list, &tls_device_down_list);
1355                 spin_unlock_irqrestore(&tls_device_lock, flags);
1356
1357                 /* Device contexts for RX and TX will be freed in on sk_destruct
1358                  * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW.
1359                  * Now release the ref taken above.
1360                  */
1361                 if (refcount_dec_and_test(&ctx->refcount)) {
1362                         /* sk_destruct ran after tls_device_down took a ref, and
1363                          * it returned early. Complete the destruction here.
1364                          */
1365                         list_del(&ctx->list);
1366                         tls_device_free_ctx(ctx);
1367                 }
1368         }
1369
1370         up_write(&device_offload_lock);
1371
1372         flush_workqueue(destruct_wq);
1373
1374         return NOTIFY_DONE;
1375 }
1376
1377 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1378                          void *ptr)
1379 {
1380         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1381
1382         if (!dev->tlsdev_ops &&
1383             !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1384                 return NOTIFY_DONE;
1385
1386         switch (event) {
1387         case NETDEV_REGISTER:
1388         case NETDEV_FEAT_CHANGE:
1389                 if (netif_is_bond_master(dev))
1390                         return NOTIFY_DONE;
1391                 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1392                     !dev->tlsdev_ops->tls_dev_resync)
1393                         return NOTIFY_BAD;
1394
1395                 if  (dev->tlsdev_ops &&
1396                      dev->tlsdev_ops->tls_dev_add &&
1397                      dev->tlsdev_ops->tls_dev_del)
1398                         return NOTIFY_DONE;
1399                 else
1400                         return NOTIFY_BAD;
1401         case NETDEV_DOWN:
1402                 return tls_device_down(dev);
1403         }
1404         return NOTIFY_DONE;
1405 }
1406
1407 static struct notifier_block tls_dev_notifier = {
1408         .notifier_call  = tls_dev_event,
1409 };
1410
1411 int __init tls_device_init(void)
1412 {
1413         int err;
1414
1415         dummy_page = alloc_page(GFP_KERNEL);
1416         if (!dummy_page)
1417                 return -ENOMEM;
1418
1419         destruct_wq = alloc_workqueue("ktls_device_destruct", 0, 0);
1420         if (!destruct_wq) {
1421                 err = -ENOMEM;
1422                 goto err_free_dummy;
1423         }
1424
1425         err = register_netdevice_notifier(&tls_dev_notifier);
1426         if (err)
1427                 goto err_destroy_wq;
1428
1429         return 0;
1430
1431 err_destroy_wq:
1432         destroy_workqueue(destruct_wq);
1433 err_free_dummy:
1434         put_page(dummy_page);
1435         return err;
1436 }
1437
1438 void __exit tls_device_cleanup(void)
1439 {
1440         unregister_netdevice_notifier(&tls_dev_notifier);
1441         destroy_workqueue(destruct_wq);
1442         clean_acked_data_flush();
1443         put_page(dummy_page);
1444 }