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                 rc = tls_device_copy_data(page_address(pfrag->page) +
 487                                           pfrag->offset, copy, msg_iter);
 488                 if (rc)
 489                         goto handle_error;
 490                 tls_append_frag(record, pfrag, copy);
 491
 492                 size -= copy;
 493                 if (!size) {
 494 last_record:
 495                         tls_push_record_flags = flags;
 496                         if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) {
 497                                 more = true;
 498                                 break;
 499                         }
 500
 501                         done = true;
 502                 }
 503
 504                 if (done || record->len >= max_open_record_len ||
 505                     (record->num_frags >= MAX_SKB_FRAGS - 1)) {
 506                         rc = tls_device_record_close(sk, tls_ctx, record,
 507                                                      pfrag, record_type);
 508                         if (rc) {
 509                                 if (rc > 0) {
 510                                         size += rc;
 511                                 } else {
 512                                         size = orig_size;
 513                                         destroy_record(record);
 514                                         ctx->open_record = NULL;
 515                                         break;
 516                                 }
 517                         }
 518
 519                         rc = tls_push_record(sk,
 520                                              tls_ctx,
 521                                              ctx,
 522                                              record,
 523                                              tls_push_record_flags);
 524                         if (rc < 0)
 525                                 break;
 526                 }
 527         } while (!done);
 528
 529         tls_ctx->pending_open_record_frags = more;
 530
 531         if (orig_size - size > 0)
 532                 rc = orig_size - size;
 533
 534         return rc;
 535 }
 536
 537 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 538 {
 539         unsigned char record_type = TLS_RECORD_TYPE_DATA;
 540         struct tls_context *tls_ctx = tls_get_ctx(sk);
 541         int rc;
 542
 543         mutex_lock(&tls_ctx->tx_lock);
 544         lock_sock(sk);
 545
 546         if (unlikely(msg->msg_controllen)) {
 547                 rc = tls_proccess_cmsg(sk, msg, &record_type);
 548                 if (rc)
 549                         goto out;
 550         }
 551
 552         rc = tls_push_data(sk, &msg->msg_iter, size,
 553                            msg->msg_flags, record_type);
 554
 555 out:
 556         release_sock(sk);
 557         mutex_unlock(&tls_ctx->tx_lock);
 558         return rc;
 559 }
 560
 561 int tls_device_sendpage(struct sock *sk, struct page *page,
 562                         int offset, size_t size, int flags)
 563 {
 564         struct tls_context *tls_ctx = tls_get_ctx(sk);
 565         struct iov_iter msg_iter;
 566         char *kaddr;
 567         struct kvec iov;
 568         int rc;
 569
 570         if (flags & MSG_SENDPAGE_NOTLAST)
 571                 flags |= MSG_MORE;
 572
 573         mutex_lock(&tls_ctx->tx_lock);
 574         lock_sock(sk);
 575
 576         if (flags & MSG_OOB) {
 577                 rc = -EOPNOTSUPP;
 578                 goto out;
 579         }
 580
 581         kaddr = kmap(page);
 582         iov.iov_base = kaddr + offset;
 583         iov.iov_len = size;
 584         iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);
 585         rc = tls_push_data(sk, &msg_iter, size,
 586                            flags, TLS_RECORD_TYPE_DATA);
 587         kunmap(page);
 588
 589 out:
 590         release_sock(sk);
 591         mutex_unlock(&tls_ctx->tx_lock);
 592         return rc;
 593 }
 594
 595 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
 596                                        u32 seq, u64 *p_record_sn)
 597 {
 598         u64 record_sn = context->hint_record_sn;
 599         struct tls_record_info *info, *last;
 600
 601         info = context->retransmit_hint;
 602         if (!info ||
 603             before(seq, info->end_seq - info->len)) {
 604                 /* if retransmit_hint is irrelevant start
 605                  * from the beginning of the list
 606                  */
 607                 info = list_first_entry_or_null(&context->records_list,
 608                                                 struct tls_record_info, list);
 609                 if (!info)
 610                         return NULL;
 611                 /* send the start_marker record if seq number is before the
 612                  * tls offload start marker sequence number. This record is
 613                  * required to handle TCP packets which are before TLS offload
 614                  * started.
 615                  *  And if it's not start marker, look if this seq number
 616                  * belongs to the list.
 617                  */
 618                 if (likely(!tls_record_is_start_marker(info))) {
 619                         /* we have the first record, get the last record to see
 620                          * if this seq number belongs to the list.
 621                          */
 622                         last = list_last_entry(&context->records_list,
 623                                                struct tls_record_info, list);
 624
 625                         if (!between(seq, tls_record_start_seq(info),
 626                                      last->end_seq))
 627                                 return NULL;
 628                 }
 629                 record_sn = context->unacked_record_sn;
 630         }
 631
 632         /* We just need the _rcu for the READ_ONCE() */
 633         rcu_read_lock();
 634         list_for_each_entry_from_rcu(info, &context->records_list, list) {
 635                 if (before(seq, info->end_seq)) {
 636                         if (!context->retransmit_hint ||
 637                             after(info->end_seq,
 638                                   context->retransmit_hint->end_seq)) {
 639                                 context->hint_record_sn = record_sn;
 640                                 context->retransmit_hint = info;
 641                         }
 642                         *p_record_sn = record_sn;
 643                         goto exit_rcu_unlock;
 644                 }
 645                 record_sn++;
 646         }
 647         info = NULL;
 648
 649 exit_rcu_unlock:
 650         rcu_read_unlock();
 651         return info;
 652 }
 653 EXPORT_SYMBOL(tls_get_record);
 654
 655 static int tls_device_push_pending_record(struct sock *sk, int flags)
 656 {
 657         struct iov_iter msg_iter;
 658
 659         iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0);
 660         return tls_push_data(sk, &msg_iter, 0, flags, TLS_RECORD_TYPE_DATA);
 661 }
 662
 663 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 664 {
 665         if (tls_is_partially_sent_record(ctx)) {
 666                 gfp_t sk_allocation = sk->sk_allocation;
 667
 668                 WARN_ON_ONCE(sk->sk_write_pending);
 669
 670                 sk->sk_allocation = GFP_ATOMIC;
 671                 tls_push_partial_record(sk, ctx,
 672                                         MSG_DONTWAIT | MSG_NOSIGNAL |
 673                                         MSG_SENDPAGE_DECRYPTED);
 674                 sk->sk_allocation = sk_allocation;
 675         }
 676 }
 677
 678 static void tls_device_resync_rx(struct tls_context *tls_ctx,
 679                                  struct sock *sk, u32 seq, u8 *rcd_sn)
 680 {
 681         struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
 682         struct net_device *netdev;
 683
 684         trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
 685         rcu_read_lock();
 686         netdev = READ_ONCE(tls_ctx->netdev);
 687         if (netdev)
 688                 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
 689                                                    TLS_OFFLOAD_CTX_DIR_RX);
 690         rcu_read_unlock();
 691         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
 692 }
 693
 694 static bool
 695 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
 696                            s64 resync_req, u32 *seq, u16 *rcd_delta)
 697 {
 698         u32 is_async = resync_req & RESYNC_REQ_ASYNC;
 699         u32 req_seq = resync_req >> 32;
 700         u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
 701         u16 i;
 702
 703         *rcd_delta = 0;
 704
 705         if (is_async) {
 706                 /* shouldn't get to wraparound:
 707                  * too long in async stage, something bad happened
 708                  */
 709                 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
 710                         return false;
 711
 712                 /* asynchronous stage: log all headers seq such that
 713                  * req_seq <= seq <= end_seq, and wait for real resync request
 714                  */
 715                 if (before(*seq, req_seq))
 716                         return false;
 717                 if (!after(*seq, req_end) &&
 718                     resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
 719                         resync_async->log[resync_async->loglen++] = *seq;
 720
 721                 resync_async->rcd_delta++;
 722
 723                 return false;
 724         }
 725
 726         /* synchronous stage: check against the logged entries and
 727          * proceed to check the next entries if no match was found
 728          */
 729         for (i = 0; i < resync_async->loglen; i++)
 730                 if (req_seq == resync_async->log[i] &&
 731                     atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) {
 732                         *rcd_delta = resync_async->rcd_delta - i;
 733                         *seq = req_seq;
 734                         resync_async->loglen = 0;
 735                         resync_async->rcd_delta = 0;
 736                         return true;
 737                 }
 738
 739         resync_async->loglen = 0;
 740         resync_async->rcd_delta = 0;
 741
 742         if (req_seq == *seq &&
 743             atomic64_try_cmpxchg(&resync_async->req,
 744                                  &resync_req, 0))
 745                 return true;
 746
 747         return false;
 748 }
 749
 750 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
 751 {
 752         struct tls_context *tls_ctx = tls_get_ctx(sk);
 753         struct tls_offload_context_rx *rx_ctx;
 754         u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 755         u32 sock_data, is_req_pending;
 756         struct tls_prot_info *prot;
 757         s64 resync_req;
 758         u16 rcd_delta;
 759         u32 req_seq;
 760
 761         if (tls_ctx->rx_conf != TLS_HW)
 762                 return;
 763         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags)))
 764                 return;
 765
 766         prot = &tls_ctx->prot_info;
 767         rx_ctx = tls_offload_ctx_rx(tls_ctx);
 768         memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 769
 770         switch (rx_ctx->resync_type) {
 771         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
 772                 resync_req = atomic64_read(&rx_ctx->resync_req);
 773                 req_seq = resync_req >> 32;
 774                 seq += TLS_HEADER_SIZE - 1;
 775                 is_req_pending = resync_req;
 776
 777                 if (likely(!is_req_pending) || req_seq != seq ||
 778                     !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
 779                         return;
 780                 break;
 781         case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
 782                 if (likely(!rx_ctx->resync_nh_do_now))
 783                         return;
 784
 785                 /* head of next rec is already in, note that the sock_inq will
 786                  * include the currently parsed message when called from parser
 787                  */
 788                 sock_data = tcp_inq(sk);
 789                 if (sock_data > rcd_len) {
 790                         trace_tls_device_rx_resync_nh_delay(sk, sock_data,
 791                                                             rcd_len);
 792                         return;
 793                 }
 794
 795                 rx_ctx->resync_nh_do_now = 0;
 796                 seq += rcd_len;
 797                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 798                 break;
 799         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
 800                 resync_req = atomic64_read(&rx_ctx->resync_async->req);
 801                 is_req_pending = resync_req;
 802                 if (likely(!is_req_pending))
 803                         return;
 804
 805                 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
 806                                                 resync_req, &seq, &rcd_delta))
 807                         return;
 808                 tls_bigint_subtract(rcd_sn, rcd_delta);
 809                 break;
 810         }
 811
 812         tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
 813 }
 814
 815 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
 816                                            struct tls_offload_context_rx *ctx,
 817                                            struct sock *sk, struct sk_buff *skb)
 818 {
 819         struct strp_msg *rxm;
 820
 821         /* device will request resyncs by itself based on stream scan */
 822         if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
 823                 return;
 824         /* already scheduled */
 825         if (ctx->resync_nh_do_now)
 826                 return;
 827         /* seen decrypted fragments since last fully-failed record */
 828         if (ctx->resync_nh_reset) {
 829                 ctx->resync_nh_reset = 0;
 830                 ctx->resync_nh.decrypted_failed = 1;
 831                 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
 832                 return;
 833         }
 834
 835         if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
 836                 return;
 837
 838         /* doing resync, bump the next target in case it fails */
 839         if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
 840                 ctx->resync_nh.decrypted_tgt *= 2;
 841         else
 842                 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
 843
 844         rxm = strp_msg(skb);
 845
 846         /* head of next rec is already in, parser will sync for us */
 847         if (tcp_inq(sk) > rxm->full_len) {
 848                 trace_tls_device_rx_resync_nh_schedule(sk);
 849                 ctx->resync_nh_do_now = 1;
 850         } else {
 851                 struct tls_prot_info *prot = &tls_ctx->prot_info;
 852                 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 853
 854                 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 855                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 856
 857                 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
 858                                      rcd_sn);
 859         }
 860 }
 861
 862 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)
 863 {
 864         struct strp_msg *rxm = strp_msg(skb);
 865         int err = 0, offset = rxm->offset, copy, nsg, data_len, pos;
 866         struct sk_buff *skb_iter, *unused;
 867         struct scatterlist sg[1];
 868         char *orig_buf, *buf;
 869
 870         orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE +
 871                            TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation);
 872         if (!orig_buf)
 873                 return -ENOMEM;
 874         buf = orig_buf;
 875
 876         nsg = skb_cow_data(skb, 0, &unused);
 877         if (unlikely(nsg < 0)) {
 878                 err = nsg;
 879                 goto free_buf;
 880         }
 881
 882         sg_init_table(sg, 1);
 883         sg_set_buf(&sg[0], buf,
 884                    rxm->full_len + TLS_HEADER_SIZE +
 885                    TLS_CIPHER_AES_GCM_128_IV_SIZE);
 886         err = skb_copy_bits(skb, offset, buf,
 887                             TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
 888         if (err)
 889                 goto free_buf;
 890
 891         /* We are interested only in the decrypted data not the auth */
 892         err = decrypt_skb(sk, skb, sg);
 893         if (err != -EBADMSG)
 894                 goto free_buf;
 895         else
 896                 err = 0;
 897
 898         data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE;
 899
 900         if (skb_pagelen(skb) > offset) {
 901                 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 902
 903                 if (skb->decrypted) {
 904                         err = skb_store_bits(skb, offset, buf, copy);
 905                         if (err)
 906                                 goto free_buf;
 907                 }
 908
 909                 offset += copy;
 910                 buf += copy;
 911         }
 912
 913         pos = skb_pagelen(skb);
 914         skb_walk_frags(skb, skb_iter) {
 915                 int frag_pos;
 916
 917                 /* Practically all frags must belong to msg if reencrypt
 918                  * is needed with current strparser and coalescing logic,
 919                  * but strparser may "get optimized", so let's be safe.
 920                  */
 921                 if (pos + skb_iter->len <= offset)
 922                         goto done_with_frag;
 923                 if (pos >= data_len + rxm->offset)
 924                         break;
 925
 926                 frag_pos = offset - pos;
 927                 copy = min_t(int, skb_iter->len - frag_pos,
 928                              data_len + rxm->offset - offset);
 929
 930                 if (skb_iter->decrypted) {
 931                         err = skb_store_bits(skb_iter, frag_pos, buf, copy);
 932                         if (err)
 933                                 goto free_buf;
 934                 }
 935
 936                 offset += copy;
 937                 buf += copy;
 938 done_with_frag:
 939                 pos += skb_iter->len;
 940         }
 941
 942 free_buf:
 943         kfree(orig_buf);
 944         return err;
 945 }
 946
 947 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx,
 948                          struct sk_buff *skb, struct strp_msg *rxm)
 949 {
 950         struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
 951         int is_decrypted = skb->decrypted;
 952         int is_encrypted = !is_decrypted;
 953         struct sk_buff *skb_iter;
 954
 955         /* Check if all the data is decrypted already */
 956         skb_walk_frags(skb, skb_iter) {
 957                 is_decrypted &= skb_iter->decrypted;
 958                 is_encrypted &= !skb_iter->decrypted;
 959         }
 960
 961         trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
 962                                    tls_ctx->rx.rec_seq, rxm->full_len,
 963                                    is_encrypted, is_decrypted);
 964
 965         ctx->sw.decrypted |= is_decrypted;
 966
 967         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) {
 968                 if (likely(is_encrypted || is_decrypted))
 969                         return 0;
 970
 971                 /* After tls_device_down disables the offload, the next SKB will
 972                  * likely have initial fragments decrypted, and final ones not
 973                  * decrypted. We need to reencrypt that single SKB.
 974                  */
 975                 return tls_device_reencrypt(sk, skb);
 976         }
 977
 978         /* Return immediately if the record is either entirely plaintext or
 979          * entirely ciphertext. Otherwise handle reencrypt partially decrypted
 980          * record.
 981          */
 982         if (is_decrypted) {
 983                 ctx->resync_nh_reset = 1;
 984                 return 0;
 985         }
 986         if (is_encrypted) {
 987                 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
 988                 return 0;
 989         }
 990
 991         ctx->resync_nh_reset = 1;
 992         return tls_device_reencrypt(sk, skb);
 993 }
 994
 995 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
 996                               struct net_device *netdev)
 997 {
 998         if (sk->sk_destruct != tls_device_sk_destruct) {
 999                 refcount_set(&ctx->refcount, 1);
1000                 dev_hold(netdev);
1001                 ctx->netdev = netdev;
1002                 spin_lock_irq(&tls_device_lock);
1003                 list_add_tail(&ctx->list, &tls_device_list);
1004                 spin_unlock_irq(&tls_device_lock);
1005
1006                 ctx->sk_destruct = sk->sk_destruct;
1007                 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
1008         }
1009 }
1010
1011 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
1012 {
1013         u16 nonce_size, tag_size, iv_size, rec_seq_size, salt_size;
1014         struct tls_context *tls_ctx = tls_get_ctx(sk);
1015         struct tls_prot_info *prot = &tls_ctx->prot_info;
1016         struct tls_record_info *start_marker_record;
1017         struct tls_offload_context_tx *offload_ctx;
1018         struct tls_crypto_info *crypto_info;
1019         struct net_device *netdev;
1020         char *iv, *rec_seq;
1021         struct sk_buff *skb;
1022         __be64 rcd_sn;
1023         int rc;
1024
1025         if (!ctx)
1026                 return -EINVAL;
1027
1028         if (ctx->priv_ctx_tx)
1029                 return -EEXIST;
1030
1031         start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1032         if (!start_marker_record)
1033                 return -ENOMEM;
1034
1035         offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
1036         if (!offload_ctx) {
1037                 rc = -ENOMEM;
1038                 goto free_marker_record;
1039         }
1040
1041         crypto_info = &ctx->crypto_send.info;
1042         if (crypto_info->version != TLS_1_2_VERSION) {
1043                 rc = -EOPNOTSUPP;
1044                 goto free_offload_ctx;
1045         }
1046
1047         switch (crypto_info->cipher_type) {
1048         case TLS_CIPHER_AES_GCM_128:
1049                 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1050                 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
1051                 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1052                 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
1053                 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
1054                 salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
1055                 rec_seq =
1056                  ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
1057                 break;
1058         default:
1059                 rc = -EINVAL;
1060                 goto free_offload_ctx;
1061         }
1062
1063         /* Sanity-check the rec_seq_size for stack allocations */
1064         if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
1065                 rc = -EINVAL;
1066                 goto free_offload_ctx;
1067         }
1068
1069         prot->version = crypto_info->version;
1070         prot->cipher_type = crypto_info->cipher_type;
1071         prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
1072         prot->tag_size = tag_size;
1073         prot->overhead_size = prot->prepend_size + prot->tag_size;
1074         prot->iv_size = iv_size;
1075         prot->salt_size = salt_size;
1076         ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
1077                              GFP_KERNEL);
1078         if (!ctx->tx.iv) {
1079                 rc = -ENOMEM;
1080                 goto free_offload_ctx;
1081         }
1082
1083         memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
1084
1085         prot->rec_seq_size = rec_seq_size;
1086         ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
1087         if (!ctx->tx.rec_seq) {
1088                 rc = -ENOMEM;
1089                 goto free_iv;
1090         }
1091
1092         rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1093         if (rc)
1094                 goto free_rec_seq;
1095
1096         /* start at rec_seq - 1 to account for the start marker record */
1097         memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1098         offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1099
1100         start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1101         start_marker_record->len = 0;
1102         start_marker_record->num_frags = 0;
1103
1104         INIT_LIST_HEAD(&offload_ctx->records_list);
1105         list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1106         spin_lock_init(&offload_ctx->lock);
1107         sg_init_table(offload_ctx->sg_tx_data,
1108                       ARRAY_SIZE(offload_ctx->sg_tx_data));
1109
1110         clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1111         ctx->push_pending_record = tls_device_push_pending_record;
1112
1113         /* TLS offload is greatly simplified if we don't send
1114          * SKBs where only part of the payload needs to be encrypted.
1115          * So mark the last skb in the write queue as end of record.
1116          */
1117         skb = tcp_write_queue_tail(sk);
1118         if (skb)
1119                 TCP_SKB_CB(skb)->eor = 1;
1120
1121         netdev = get_netdev_for_sock(sk);
1122         if (!netdev) {
1123                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1124                 rc = -EINVAL;
1125                 goto disable_cad;
1126         }
1127
1128         if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1129                 rc = -EOPNOTSUPP;
1130                 goto release_netdev;
1131         }
1132
1133         /* Avoid offloading if the device is down
1134          * We don't want to offload new flows after
1135          * the NETDEV_DOWN event
1136          *
1137          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1138          * handler thus protecting from the device going down before
1139          * ctx was added to tls_device_list.
1140          */
1141         down_read(&device_offload_lock);
1142         if (!(netdev->flags & IFF_UP)) {
1143                 rc = -EINVAL;
1144                 goto release_lock;
1145         }
1146
1147         ctx->priv_ctx_tx = offload_ctx;
1148         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1149                                              &ctx->crypto_send.info,
1150                                              tcp_sk(sk)->write_seq);
1151         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1152                                      tcp_sk(sk)->write_seq, rec_seq, rc);
1153         if (rc)
1154                 goto release_lock;
1155
1156         tls_device_attach(ctx, sk, netdev);
1157         up_read(&device_offload_lock);
1158
1159         /* following this assignment tls_is_sk_tx_device_offloaded
1160          * will return true and the context might be accessed
1161          * by the netdev's xmit function.
1162          */
1163         smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1164         dev_put(netdev);
1165
1166         return 0;
1167
1168 release_lock:
1169         up_read(&device_offload_lock);
1170 release_netdev:
1171         dev_put(netdev);
1172 disable_cad:
1173         clean_acked_data_disable(inet_csk(sk));
1174         crypto_free_aead(offload_ctx->aead_send);
1175 free_rec_seq:
1176         kfree(ctx->tx.rec_seq);
1177 free_iv:
1178         kfree(ctx->tx.iv);
1179 free_offload_ctx:
1180         kfree(offload_ctx);
1181         ctx->priv_ctx_tx = NULL;
1182 free_marker_record:
1183         kfree(start_marker_record);
1184         return rc;
1185 }
1186
1187 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1188 {
1189         struct tls12_crypto_info_aes_gcm_128 *info;
1190         struct tls_offload_context_rx *context;
1191         struct net_device *netdev;
1192         int rc = 0;
1193
1194         if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1195                 return -EOPNOTSUPP;
1196
1197         netdev = get_netdev_for_sock(sk);
1198         if (!netdev) {
1199                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1200                 return -EINVAL;
1201         }
1202
1203         if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1204                 rc = -EOPNOTSUPP;
1205                 goto release_netdev;
1206         }
1207
1208         /* Avoid offloading if the device is down
1209          * We don't want to offload new flows after
1210          * the NETDEV_DOWN event
1211          *
1212          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1213          * handler thus protecting from the device going down before
1214          * ctx was added to tls_device_list.
1215          */
1216         down_read(&device_offload_lock);
1217         if (!(netdev->flags & IFF_UP)) {
1218                 rc = -EINVAL;
1219                 goto release_lock;
1220         }
1221
1222         context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1223         if (!context) {
1224                 rc = -ENOMEM;
1225                 goto release_lock;
1226         }
1227         context->resync_nh_reset = 1;
1228
1229         ctx->priv_ctx_rx = context;
1230         rc = tls_set_sw_offload(sk, ctx, 0);
1231         if (rc)
1232                 goto release_ctx;
1233
1234         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1235                                              &ctx->crypto_recv.info,
1236                                              tcp_sk(sk)->copied_seq);
1237         info = (void *)&ctx->crypto_recv.info;
1238         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1239                                      tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1240         if (rc)
1241                 goto free_sw_resources;
1242
1243         tls_device_attach(ctx, sk, netdev);
1244         up_read(&device_offload_lock);
1245
1246         dev_put(netdev);
1247
1248         return 0;
1249
1250 free_sw_resources:
1251         up_read(&device_offload_lock);
1252         tls_sw_free_resources_rx(sk);
1253         down_read(&device_offload_lock);
1254 release_ctx:
1255         ctx->priv_ctx_rx = NULL;
1256 release_lock:
1257         up_read(&device_offload_lock);
1258 release_netdev:
1259         dev_put(netdev);
1260         return rc;
1261 }
1262
1263 void tls_device_offload_cleanup_rx(struct sock *sk)
1264 {
1265         struct tls_context *tls_ctx = tls_get_ctx(sk);
1266         struct net_device *netdev;
1267
1268         down_read(&device_offload_lock);
1269         netdev = tls_ctx->netdev;
1270         if (!netdev)
1271                 goto out;
1272
1273         netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1274                                         TLS_OFFLOAD_CTX_DIR_RX);
1275
1276         if (tls_ctx->tx_conf != TLS_HW) {
1277                 dev_put(netdev);
1278                 tls_ctx->netdev = NULL;
1279         } else {
1280                 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
1281         }
1282 out:
1283         up_read(&device_offload_lock);
1284         tls_sw_release_resources_rx(sk);
1285 }
1286
1287 static int tls_device_down(struct net_device *netdev)
1288 {
1289         struct tls_context *ctx, *tmp;
1290         unsigned long flags;
1291         LIST_HEAD(list);
1292
1293         /* Request a write lock to block new offload attempts */
1294         down_write(&device_offload_lock);
1295
1296         spin_lock_irqsave(&tls_device_lock, flags);
1297         list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1298                 if (ctx->netdev != netdev ||
1299                     !refcount_inc_not_zero(&ctx->refcount))
1300                         continue;
1301
1302                 list_move(&ctx->list, &list);
1303         }
1304         spin_unlock_irqrestore(&tls_device_lock, flags);
1305
1306         list_for_each_entry_safe(ctx, tmp, &list, list) {
1307                 /* Stop offloaded TX and switch to the fallback.
1308                  * tls_is_sk_tx_device_offloaded will return false.
1309                  */
1310                 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw);
1311
1312                 /* Stop the RX and TX resync.
1313                  * tls_dev_resync must not be called after tls_dev_del.
1314                  */
1315                 WRITE_ONCE(ctx->netdev, NULL);
1316
1317                 /* Start skipping the RX resync logic completely. */
1318                 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags);
1319
1320                 /* Sync with inflight packets. After this point:
1321                  * TX: no non-encrypted packets will be passed to the driver.
1322                  * RX: resync requests from the driver will be ignored.
1323                  */
1324                 synchronize_net();
1325
1326                 /* Release the offload context on the driver side. */
1327                 if (ctx->tx_conf == TLS_HW)
1328                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1329                                                         TLS_OFFLOAD_CTX_DIR_TX);
1330                 if (ctx->rx_conf == TLS_HW &&
1331                     !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags))
1332                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1333                                                         TLS_OFFLOAD_CTX_DIR_RX);
1334
1335                 dev_put(netdev);
1336
1337                 /* Move the context to a separate list for two reasons:
1338                  * 1. When the context is deallocated, list_del is called.
1339                  * 2. It's no longer an offloaded context, so we don't want to
1340                  *    run offload-specific code on this context.
1341                  */
1342                 spin_lock_irqsave(&tls_device_lock, flags);
1343                 list_move_tail(&ctx->list, &tls_device_down_list);
1344                 spin_unlock_irqrestore(&tls_device_lock, flags);
1345
1346                 /* Device contexts for RX and TX will be freed in on sk_destruct
1347                  * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW.
1348                  */
1349         }
1350
1351         up_write(&device_offload_lock);
1352
1353         flush_work(&tls_device_gc_work);
1354
1355         return NOTIFY_DONE;
1356 }
1357
1358 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1359                          void *ptr)
1360 {
1361         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1362
1363         if (!dev->tlsdev_ops &&
1364             !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1365                 return NOTIFY_DONE;
1366
1367         switch (event) {
1368         case NETDEV_REGISTER:
1369         case NETDEV_FEAT_CHANGE:
1370                 if (netif_is_bond_master(dev))
1371                         return NOTIFY_DONE;
1372                 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1373                     !dev->tlsdev_ops->tls_dev_resync)
1374                         return NOTIFY_BAD;
1375
1376                 if  (dev->tlsdev_ops &&
1377                      dev->tlsdev_ops->tls_dev_add &&
1378                      dev->tlsdev_ops->tls_dev_del)
1379                         return NOTIFY_DONE;
1380                 else
1381                         return NOTIFY_BAD;
1382         case NETDEV_DOWN:
1383                 return tls_device_down(dev);
1384         }
1385         return NOTIFY_DONE;
1386 }
1387
1388 static struct notifier_block tls_dev_notifier = {
1389         .notifier_call  = tls_dev_event,
1390 };
1391
1392 void __init tls_device_init(void)
1393 {
1394         register_netdevice_notifier(&tls_dev_notifier);
1395 }
1396
1397 void __exit tls_device_cleanup(void)
1398 {
1399         unregister_netdevice_notifier(&tls_dev_notifier);
1400         flush_work(&tls_device_gc_work);
1401         clean_acked_data_flush();
1402 }