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 void tls_device_gc_task(struct work_struct *work);
  50
  51 static DECLARE_WORK(tls_device_gc_work, tls_device_gc_task);
  52 static LIST_HEAD(tls_device_gc_list);
  53 static LIST_HEAD(tls_device_list);
  54 static LIST_HEAD(tls_device_down_list);
  55 static DEFINE_SPINLOCK(tls_device_lock);
  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                 kfree(ctx->tx.rec_seq);
  62                 kfree(ctx->tx.iv);
  63         }
  64
  65         if (ctx->rx_conf == TLS_HW)
  66                 kfree(tls_offload_ctx_rx(ctx));
  67
  68         tls_ctx_free(NULL, ctx);
  69 }
  70
  71 static void tls_device_gc_task(struct work_struct *work)
  72 {
  73         struct tls_context *ctx, *tmp;
  74         unsigned long flags;
  75         LIST_HEAD(gc_list);
  76
  77         spin_lock_irqsave(&tls_device_lock, flags);
  78         list_splice_init(&tls_device_gc_list, &gc_list);
  79         spin_unlock_irqrestore(&tls_device_lock, flags);
  80
  81         list_for_each_entry_safe(ctx, tmp, &gc_list, list) {
  82                 struct net_device *netdev = ctx->netdev;
  83
  84                 if (netdev && ctx->tx_conf == TLS_HW) {
  85                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
  86                                                         TLS_OFFLOAD_CTX_DIR_TX);
  87                         dev_put(netdev);
  88                         ctx->netdev = NULL;
  89                 }
  90
  91                 list_del(&ctx->list);
  92                 tls_device_free_ctx(ctx);
  93         }
  94 }
  95
  96 static void tls_device_queue_ctx_destruction(struct tls_context *ctx)
  97 {
  98         unsigned long flags;
  99
 100         spin_lock_irqsave(&tls_device_lock, flags);
 101         if (unlikely(!refcount_dec_and_test(&ctx->refcount)))
 102                 goto unlock;
 103
 104         list_move_tail(&ctx->list, &tls_device_gc_list);
 105
 106         /* schedule_work inside the spinlock
 107          * to make sure tls_device_down waits for that work.
 108          */
 109         schedule_work(&tls_device_gc_work);
 110 unlock:
 111         spin_unlock_irqrestore(&tls_device_lock, flags);
 112 }
 113
 114 /* We assume that the socket is already connected */
 115 static struct net_device *get_netdev_for_sock(struct sock *sk)
 116 {
 117         struct dst_entry *dst = sk_dst_get(sk);
 118         struct net_device *netdev = NULL;
 119
 120         if (likely(dst)) {
 121                 netdev = netdev_sk_get_lowest_dev(dst->dev, sk);
 122                 dev_hold(netdev);
 123         }
 124
 125         dst_release(dst);
 126
 127         return netdev;
 128 }
 129
 130 static void destroy_record(struct tls_record_info *record)
 131 {
 132         int i;
 133
 134         for (i = 0; i < record->num_frags; i++)
 135                 __skb_frag_unref(&record->frags[i], false);
 136         kfree(record);
 137 }
 138
 139 static void delete_all_records(struct tls_offload_context_tx *offload_ctx)
 140 {
 141         struct tls_record_info *info, *temp;
 142
 143         list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) {
 144                 list_del(&info->list);
 145                 destroy_record(info);
 146         }
 147
 148         offload_ctx->retransmit_hint = NULL;
 149 }
 150
 151 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq)
 152 {
 153         struct tls_context *tls_ctx = tls_get_ctx(sk);
 154         struct tls_record_info *info, *temp;
 155         struct tls_offload_context_tx *ctx;
 156         u64 deleted_records = 0;
 157         unsigned long flags;
 158
 159         if (!tls_ctx)
 160                 return;
 161
 162         ctx = tls_offload_ctx_tx(tls_ctx);
 163
 164         spin_lock_irqsave(&ctx->lock, flags);
 165         info = ctx->retransmit_hint;
 166         if (info && !before(acked_seq, info->end_seq))
 167                 ctx->retransmit_hint = NULL;
 168
 169         list_for_each_entry_safe(info, temp, &ctx->records_list, list) {
 170                 if (before(acked_seq, info->end_seq))
 171                         break;
 172                 list_del(&info->list);
 173
 174                 destroy_record(info);
 175                 deleted_records++;
 176         }
 177
 178         ctx->unacked_record_sn += deleted_records;
 179         spin_unlock_irqrestore(&ctx->lock, flags);
 180 }
 181
 182 /* At this point, there should be no references on this
 183  * socket and no in-flight SKBs associated with this
 184  * socket, so it is safe to free all the resources.
 185  */
 186 void tls_device_sk_destruct(struct sock *sk)
 187 {
 188         struct tls_context *tls_ctx = tls_get_ctx(sk);
 189         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 190
 191         tls_ctx->sk_destruct(sk);
 192
 193         if (tls_ctx->tx_conf == TLS_HW) {
 194                 if (ctx->open_record)
 195                         destroy_record(ctx->open_record);
 196                 delete_all_records(ctx);
 197                 crypto_free_aead(ctx->aead_send);
 198                 clean_acked_data_disable(inet_csk(sk));
 199         }
 200
 201         tls_device_queue_ctx_destruction(tls_ctx);
 202 }
 203 EXPORT_SYMBOL_GPL(tls_device_sk_destruct);
 204
 205 void tls_device_free_resources_tx(struct sock *sk)
 206 {
 207         struct tls_context *tls_ctx = tls_get_ctx(sk);
 208
 209         tls_free_partial_record(sk, tls_ctx);
 210 }
 211
 212 void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq)
 213 {
 214         struct tls_context *tls_ctx = tls_get_ctx(sk);
 215
 216         trace_tls_device_tx_resync_req(sk, got_seq, exp_seq);
 217         WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags));
 218 }
 219 EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request);
 220
 221 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
 222                                  u32 seq)
 223 {
 224         struct net_device *netdev;
 225         struct sk_buff *skb;
 226         int err = 0;
 227         u8 *rcd_sn;
 228
 229         skb = tcp_write_queue_tail(sk);
 230         if (skb)
 231                 TCP_SKB_CB(skb)->eor = 1;
 232
 233         rcd_sn = tls_ctx->tx.rec_seq;
 234
 235         trace_tls_device_tx_resync_send(sk, seq, rcd_sn);
 236         down_read(&device_offload_lock);
 237         netdev = tls_ctx->netdev;
 238         if (netdev)
 239                 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq,
 240                                                          rcd_sn,
 241                                                          TLS_OFFLOAD_CTX_DIR_TX);
 242         up_read(&device_offload_lock);
 243         if (err)
 244                 return;
 245
 246         clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
 247 }
 248
 249 static void tls_append_frag(struct tls_record_info *record,
 250                             struct page_frag *pfrag,
 251                             int size)
 252 {
 253         skb_frag_t *frag;
 254
 255         frag = &record->frags[record->num_frags - 1];
 256         if (skb_frag_page(frag) == pfrag->page &&
 257             skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
 258                 skb_frag_size_add(frag, size);
 259         } else {
 260                 ++frag;
 261                 __skb_frag_set_page(frag, pfrag->page);
 262                 skb_frag_off_set(frag, pfrag->offset);
 263                 skb_frag_size_set(frag, size);
 264                 ++record->num_frags;
 265                 get_page(pfrag->page);
 266         }
 267
 268         pfrag->offset += size;
 269         record->len += size;
 270 }
 271
 272 static int tls_push_record(struct sock *sk,
 273                            struct tls_context *ctx,
 274                            struct tls_offload_context_tx *offload_ctx,
 275                            struct tls_record_info *record,
 276                            int flags)
 277 {
 278         struct tls_prot_info *prot = &ctx->prot_info;
 279         struct tcp_sock *tp = tcp_sk(sk);
 280         skb_frag_t *frag;
 281         int i;
 282
 283         record->end_seq = tp->write_seq + record->len;
 284         list_add_tail_rcu(&record->list, &offload_ctx->records_list);
 285         offload_ctx->open_record = NULL;
 286
 287         if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
 288                 tls_device_resync_tx(sk, ctx, tp->write_seq);
 289
 290         tls_advance_record_sn(sk, prot, &ctx->tx);
 291
 292         for (i = 0; i < record->num_frags; i++) {
 293                 frag = &record->frags[i];
 294                 sg_unmark_end(&offload_ctx->sg_tx_data[i]);
 295                 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
 296                             skb_frag_size(frag), skb_frag_off(frag));
 297                 sk_mem_charge(sk, skb_frag_size(frag));
 298                 get_page(skb_frag_page(frag));
 299         }
 300         sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
 301
 302         /* all ready, send */
 303         return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
 304 }
 305
 306 static int tls_device_record_close(struct sock *sk,
 307                                    struct tls_context *ctx,
 308                                    struct tls_record_info *record,
 309                                    struct page_frag *pfrag,
 310                                    unsigned char record_type)
 311 {
 312         struct tls_prot_info *prot = &ctx->prot_info;
 313         int ret;
 314
 315         /* append tag
 316          * device will fill in the tag, we just need to append a placeholder
 317          * use socket memory to improve coalescing (re-using a single buffer
 318          * increases frag count)
 319          * if we can't allocate memory now, steal some back from data
 320          */
 321         if (likely(skb_page_frag_refill(prot->tag_size, pfrag,
 322                                         sk->sk_allocation))) {
 323                 ret = 0;
 324                 tls_append_frag(record, pfrag, prot->tag_size);
 325         } else {
 326                 ret = prot->tag_size;
 327                 if (record->len <= prot->overhead_size)
 328                         return -ENOMEM;
 329         }
 330
 331         /* fill prepend */
 332         tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
 333                          record->len - prot->overhead_size,
 334                          record_type);
 335         return ret;
 336 }
 337
 338 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
 339                                  struct page_frag *pfrag,
 340                                  size_t prepend_size)
 341 {
 342         struct tls_record_info *record;
 343         skb_frag_t *frag;
 344
 345         record = kmalloc(sizeof(*record), GFP_KERNEL);
 346         if (!record)
 347                 return -ENOMEM;
 348
 349         frag = &record->frags[0];
 350         __skb_frag_set_page(frag, pfrag->page);
 351         skb_frag_off_set(frag, pfrag->offset);
 352         skb_frag_size_set(frag, prepend_size);
 353
 354         get_page(pfrag->page);
 355         pfrag->offset += prepend_size;
 356
 357         record->num_frags = 1;
 358         record->len = prepend_size;
 359         offload_ctx->open_record = record;
 360         return 0;
 361 }
 362
 363 static int tls_do_allocation(struct sock *sk,
 364                              struct tls_offload_context_tx *offload_ctx,
 365                              struct page_frag *pfrag,
 366                              size_t prepend_size)
 367 {
 368         int ret;
 369
 370         if (!offload_ctx->open_record) {
 371                 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
 372                                                    sk->sk_allocation))) {
 373                         READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
 374                         sk_stream_moderate_sndbuf(sk);
 375                         return -ENOMEM;
 376                 }
 377
 378                 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
 379                 if (ret)
 380                         return ret;
 381
 382                 if (pfrag->size > pfrag->offset)
 383                         return 0;
 384         }
 385
 386         if (!sk_page_frag_refill(sk, pfrag))
 387                 return -ENOMEM;
 388
 389         return 0;
 390 }
 391
 392 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
 393 {
 394         size_t pre_copy, nocache;
 395
 396         pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
 397         if (pre_copy) {
 398                 pre_copy = min(pre_copy, bytes);
 399                 if (copy_from_iter(addr, pre_copy, i) != pre_copy)
 400                         return -EFAULT;
 401                 bytes -= pre_copy;
 402                 addr += pre_copy;
 403         }
 404
 405         nocache = round_down(bytes, SMP_CACHE_BYTES);
 406         if (copy_from_iter_nocache(addr, nocache, i) != nocache)
 407                 return -EFAULT;
 408         bytes -= nocache;
 409         addr += nocache;
 410
 411         if (bytes && copy_from_iter(addr, bytes, i) != bytes)
 412                 return -EFAULT;
 413
 414         return 0;
 415 }
 416
 417 union tls_iter_offset {
 418         struct iov_iter *msg_iter;
 419         int offset;
 420 };
 421
 422 static int tls_push_data(struct sock *sk,
 423                          union tls_iter_offset iter_offset,
 424                          size_t size, int flags,
 425                          unsigned char record_type,
 426                          struct page *zc_page)
 427 {
 428         struct tls_context *tls_ctx = tls_get_ctx(sk);
 429         struct tls_prot_info *prot = &tls_ctx->prot_info;
 430         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 431         struct tls_record_info *record;
 432         int tls_push_record_flags;
 433         struct page_frag *pfrag;
 434         size_t orig_size = size;
 435         u32 max_open_record_len;
 436         bool more = false;
 437         bool done = false;
 438         int copy, rc = 0;
 439         long timeo;
 440
 441         if (flags &
 442             ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
 443                 return -EOPNOTSUPP;
 444
 445         if (unlikely(sk->sk_err))
 446                 return -sk->sk_err;
 447
 448         flags |= MSG_SENDPAGE_DECRYPTED;
 449         tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST;
 450
 451         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
 452         if (tls_is_partially_sent_record(tls_ctx)) {
 453                 rc = tls_push_partial_record(sk, tls_ctx, flags);
 454                 if (rc < 0)
 455                         return rc;
 456         }
 457
 458         pfrag = sk_page_frag(sk);
 459
 460         /* TLS_HEADER_SIZE is not counted as part of the TLS record, and
 461          * we need to leave room for an authentication tag.
 462          */
 463         max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
 464                               prot->prepend_size;
 465         do {
 466                 rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
 467                 if (unlikely(rc)) {
 468                         rc = sk_stream_wait_memory(sk, &timeo);
 469                         if (!rc)
 470                                 continue;
 471
 472                         record = ctx->open_record;
 473                         if (!record)
 474                                 break;
 475 handle_error:
 476                         if (record_type != TLS_RECORD_TYPE_DATA) {
 477                                 /* avoid sending partial
 478                                  * record with type !=
 479                                  * application_data
 480                                  */
 481                                 size = orig_size;
 482                                 destroy_record(record);
 483                                 ctx->open_record = NULL;
 484                         } else if (record->len > prot->prepend_size) {
 485                                 goto last_record;
 486                         }
 487
 488                         break;
 489                 }
 490
 491                 record = ctx->open_record;
 492
 493                 copy = min_t(size_t, size, max_open_record_len - record->len);
 494                 if (copy && zc_page) {
 495                         struct page_frag zc_pfrag;
 496
 497                         zc_pfrag.page = zc_page;
 498                         zc_pfrag.offset = iter_offset.offset;
 499                         zc_pfrag.size = copy;
 500                         tls_append_frag(record, &zc_pfrag, copy);
 501                 } else if (copy) {
 502                         copy = min_t(size_t, copy, pfrag->size - pfrag->offset);
 503
 504                         rc = tls_device_copy_data(page_address(pfrag->page) +
 505                                                   pfrag->offset, copy,
 506                                                   iter_offset.msg_iter);
 507                         if (rc)
 508                                 goto handle_error;
 509                         tls_append_frag(record, pfrag, copy);
 510                 }
 511
 512                 size -= copy;
 513                 if (!size) {
 514 last_record:
 515                         tls_push_record_flags = flags;
 516                         if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) {
 517                                 more = true;
 518                                 break;
 519                         }
 520
 521                         done = true;
 522                 }
 523
 524                 if (done || record->len >= max_open_record_len ||
 525                     (record->num_frags >= MAX_SKB_FRAGS - 1)) {
 526                         rc = tls_device_record_close(sk, tls_ctx, record,
 527                                                      pfrag, record_type);
 528                         if (rc) {
 529                                 if (rc > 0) {
 530                                         size += rc;
 531                                 } else {
 532                                         size = orig_size;
 533                                         destroy_record(record);
 534                                         ctx->open_record = NULL;
 535                                         break;
 536                                 }
 537                         }
 538
 539                         rc = tls_push_record(sk,
 540                                              tls_ctx,
 541                                              ctx,
 542                                              record,
 543                                              tls_push_record_flags);
 544                         if (rc < 0)
 545                                 break;
 546                 }
 547         } while (!done);
 548
 549         tls_ctx->pending_open_record_frags = more;
 550
 551         if (orig_size - size > 0)
 552                 rc = orig_size - size;
 553
 554         return rc;
 555 }
 556
 557 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 558 {
 559         unsigned char record_type = TLS_RECORD_TYPE_DATA;
 560         struct tls_context *tls_ctx = tls_get_ctx(sk);
 561         union tls_iter_offset iter;
 562         int rc;
 563
 564         mutex_lock(&tls_ctx->tx_lock);
 565         lock_sock(sk);
 566
 567         if (unlikely(msg->msg_controllen)) {
 568                 rc = tls_process_cmsg(sk, msg, &record_type);
 569                 if (rc)
 570                         goto out;
 571         }
 572
 573         iter.msg_iter = &msg->msg_iter;
 574         rc = tls_push_data(sk, iter, size, msg->msg_flags, record_type, NULL);
 575
 576 out:
 577         release_sock(sk);
 578         mutex_unlock(&tls_ctx->tx_lock);
 579         return rc;
 580 }
 581
 582 int tls_device_sendpage(struct sock *sk, struct page *page,
 583                         int offset, size_t size, int flags)
 584 {
 585         struct tls_context *tls_ctx = tls_get_ctx(sk);
 586         union tls_iter_offset iter_offset;
 587         struct iov_iter msg_iter;
 588         char *kaddr;
 589         struct kvec iov;
 590         int rc;
 591
 592         if (flags & MSG_SENDPAGE_NOTLAST)
 593                 flags |= MSG_MORE;
 594
 595         mutex_lock(&tls_ctx->tx_lock);
 596         lock_sock(sk);
 597
 598         if (flags & MSG_OOB) {
 599                 rc = -EOPNOTSUPP;
 600                 goto out;
 601         }
 602
 603         if (tls_ctx->zerocopy_sendfile) {
 604                 iter_offset.offset = offset;
 605                 rc = tls_push_data(sk, iter_offset, size,
 606                                    flags, TLS_RECORD_TYPE_DATA, page);
 607                 goto out;
 608         }
 609
 610         kaddr = kmap(page);
 611         iov.iov_base = kaddr + offset;
 612         iov.iov_len = size;
 613         iov_iter_kvec(&msg_iter, WRITE, &iov, 1, size);
 614         iter_offset.msg_iter = &msg_iter;
 615         rc = tls_push_data(sk, iter_offset, size, flags, TLS_RECORD_TYPE_DATA,
 616                            NULL);
 617         kunmap(page);
 618
 619 out:
 620         release_sock(sk);
 621         mutex_unlock(&tls_ctx->tx_lock);
 622         return rc;
 623 }
 624
 625 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
 626                                        u32 seq, u64 *p_record_sn)
 627 {
 628         u64 record_sn = context->hint_record_sn;
 629         struct tls_record_info *info, *last;
 630
 631         info = context->retransmit_hint;
 632         if (!info ||
 633             before(seq, info->end_seq - info->len)) {
 634                 /* if retransmit_hint is irrelevant start
 635                  * from the beginning of the list
 636                  */
 637                 info = list_first_entry_or_null(&context->records_list,
 638                                                 struct tls_record_info, list);
 639                 if (!info)
 640                         return NULL;
 641                 /* send the start_marker record if seq number is before the
 642                  * tls offload start marker sequence number. This record is
 643                  * required to handle TCP packets which are before TLS offload
 644                  * started.
 645                  *  And if it's not start marker, look if this seq number
 646                  * belongs to the list.
 647                  */
 648                 if (likely(!tls_record_is_start_marker(info))) {
 649                         /* we have the first record, get the last record to see
 650                          * if this seq number belongs to the list.
 651                          */
 652                         last = list_last_entry(&context->records_list,
 653                                                struct tls_record_info, list);
 654
 655                         if (!between(seq, tls_record_start_seq(info),
 656                                      last->end_seq))
 657                                 return NULL;
 658                 }
 659                 record_sn = context->unacked_record_sn;
 660         }
 661
 662         /* We just need the _rcu for the READ_ONCE() */
 663         rcu_read_lock();
 664         list_for_each_entry_from_rcu(info, &context->records_list, list) {
 665                 if (before(seq, info->end_seq)) {
 666                         if (!context->retransmit_hint ||
 667                             after(info->end_seq,
 668                                   context->retransmit_hint->end_seq)) {
 669                                 context->hint_record_sn = record_sn;
 670                                 context->retransmit_hint = info;
 671                         }
 672                         *p_record_sn = record_sn;
 673                         goto exit_rcu_unlock;
 674                 }
 675                 record_sn++;
 676         }
 677         info = NULL;
 678
 679 exit_rcu_unlock:
 680         rcu_read_unlock();
 681         return info;
 682 }
 683 EXPORT_SYMBOL(tls_get_record);
 684
 685 static int tls_device_push_pending_record(struct sock *sk, int flags)
 686 {
 687         union tls_iter_offset iter;
 688         struct iov_iter msg_iter;
 689
 690         iov_iter_kvec(&msg_iter, WRITE, NULL, 0, 0);
 691         iter.msg_iter = &msg_iter;
 692         return tls_push_data(sk, iter, 0, flags, TLS_RECORD_TYPE_DATA, NULL);
 693 }
 694
 695 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 696 {
 697         if (tls_is_partially_sent_record(ctx)) {
 698                 gfp_t sk_allocation = sk->sk_allocation;
 699
 700                 WARN_ON_ONCE(sk->sk_write_pending);
 701
 702                 sk->sk_allocation = GFP_ATOMIC;
 703                 tls_push_partial_record(sk, ctx,
 704                                         MSG_DONTWAIT | MSG_NOSIGNAL |
 705                                         MSG_SENDPAGE_DECRYPTED);
 706                 sk->sk_allocation = sk_allocation;
 707         }
 708 }
 709
 710 static void tls_device_resync_rx(struct tls_context *tls_ctx,
 711                                  struct sock *sk, u32 seq, u8 *rcd_sn)
 712 {
 713         struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
 714         struct net_device *netdev;
 715
 716         trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
 717         rcu_read_lock();
 718         netdev = READ_ONCE(tls_ctx->netdev);
 719         if (netdev)
 720                 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
 721                                                    TLS_OFFLOAD_CTX_DIR_RX);
 722         rcu_read_unlock();
 723         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
 724 }
 725
 726 static bool
 727 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
 728                            s64 resync_req, u32 *seq, u16 *rcd_delta)
 729 {
 730         u32 is_async = resync_req & RESYNC_REQ_ASYNC;
 731         u32 req_seq = resync_req >> 32;
 732         u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
 733         u16 i;
 734
 735         *rcd_delta = 0;
 736
 737         if (is_async) {
 738                 /* shouldn't get to wraparound:
 739                  * too long in async stage, something bad happened
 740                  */
 741                 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
 742                         return false;
 743
 744                 /* asynchronous stage: log all headers seq such that
 745                  * req_seq <= seq <= end_seq, and wait for real resync request
 746                  */
 747                 if (before(*seq, req_seq))
 748                         return false;
 749                 if (!after(*seq, req_end) &&
 750                     resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
 751                         resync_async->log[resync_async->loglen++] = *seq;
 752
 753                 resync_async->rcd_delta++;
 754
 755                 return false;
 756         }
 757
 758         /* synchronous stage: check against the logged entries and
 759          * proceed to check the next entries if no match was found
 760          */
 761         for (i = 0; i < resync_async->loglen; i++)
 762                 if (req_seq == resync_async->log[i] &&
 763                     atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) {
 764                         *rcd_delta = resync_async->rcd_delta - i;
 765                         *seq = req_seq;
 766                         resync_async->loglen = 0;
 767                         resync_async->rcd_delta = 0;
 768                         return true;
 769                 }
 770
 771         resync_async->loglen = 0;
 772         resync_async->rcd_delta = 0;
 773
 774         if (req_seq == *seq &&
 775             atomic64_try_cmpxchg(&resync_async->req,
 776                                  &resync_req, 0))
 777                 return true;
 778
 779         return false;
 780 }
 781
 782 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
 783 {
 784         struct tls_context *tls_ctx = tls_get_ctx(sk);
 785         struct tls_offload_context_rx *rx_ctx;
 786         u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 787         u32 sock_data, is_req_pending;
 788         struct tls_prot_info *prot;
 789         s64 resync_req;
 790         u16 rcd_delta;
 791         u32 req_seq;
 792
 793         if (tls_ctx->rx_conf != TLS_HW)
 794                 return;
 795         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags)))
 796                 return;
 797
 798         prot = &tls_ctx->prot_info;
 799         rx_ctx = tls_offload_ctx_rx(tls_ctx);
 800         memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 801
 802         switch (rx_ctx->resync_type) {
 803         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
 804                 resync_req = atomic64_read(&rx_ctx->resync_req);
 805                 req_seq = resync_req >> 32;
 806                 seq += TLS_HEADER_SIZE - 1;
 807                 is_req_pending = resync_req;
 808
 809                 if (likely(!is_req_pending) || req_seq != seq ||
 810                     !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
 811                         return;
 812                 break;
 813         case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
 814                 if (likely(!rx_ctx->resync_nh_do_now))
 815                         return;
 816
 817                 /* head of next rec is already in, note that the sock_inq will
 818                  * include the currently parsed message when called from parser
 819                  */
 820                 sock_data = tcp_inq(sk);
 821                 if (sock_data > rcd_len) {
 822                         trace_tls_device_rx_resync_nh_delay(sk, sock_data,
 823                                                             rcd_len);
 824                         return;
 825                 }
 826
 827                 rx_ctx->resync_nh_do_now = 0;
 828                 seq += rcd_len;
 829                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 830                 break;
 831         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
 832                 resync_req = atomic64_read(&rx_ctx->resync_async->req);
 833                 is_req_pending = resync_req;
 834                 if (likely(!is_req_pending))
 835                         return;
 836
 837                 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
 838                                                 resync_req, &seq, &rcd_delta))
 839                         return;
 840                 tls_bigint_subtract(rcd_sn, rcd_delta);
 841                 break;
 842         }
 843
 844         tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
 845 }
 846
 847 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
 848                                            struct tls_offload_context_rx *ctx,
 849                                            struct sock *sk, struct sk_buff *skb)
 850 {
 851         struct strp_msg *rxm;
 852
 853         /* device will request resyncs by itself based on stream scan */
 854         if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
 855                 return;
 856         /* already scheduled */
 857         if (ctx->resync_nh_do_now)
 858                 return;
 859         /* seen decrypted fragments since last fully-failed record */
 860         if (ctx->resync_nh_reset) {
 861                 ctx->resync_nh_reset = 0;
 862                 ctx->resync_nh.decrypted_failed = 1;
 863                 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
 864                 return;
 865         }
 866
 867         if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
 868                 return;
 869
 870         /* doing resync, bump the next target in case it fails */
 871         if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
 872                 ctx->resync_nh.decrypted_tgt *= 2;
 873         else
 874                 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
 875
 876         rxm = strp_msg(skb);
 877
 878         /* head of next rec is already in, parser will sync for us */
 879         if (tcp_inq(sk) > rxm->full_len) {
 880                 trace_tls_device_rx_resync_nh_schedule(sk);
 881                 ctx->resync_nh_do_now = 1;
 882         } else {
 883                 struct tls_prot_info *prot = &tls_ctx->prot_info;
 884                 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 885
 886                 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 887                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 888
 889                 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
 890                                      rcd_sn);
 891         }
 892 }
 893
 894 static int
 895 tls_device_reencrypt(struct sock *sk, struct tls_sw_context_rx *sw_ctx)
 896 {
 897         int err, offset, copy, data_len, pos;
 898         struct sk_buff *skb, *skb_iter;
 899         struct scatterlist sg[1];
 900         struct strp_msg *rxm;
 901         char *orig_buf, *buf;
 902
 903         rxm = strp_msg(tls_strp_msg(sw_ctx));
 904         orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE +
 905                            TLS_CIPHER_AES_GCM_128_IV_SIZE, sk->sk_allocation);
 906         if (!orig_buf)
 907                 return -ENOMEM;
 908         buf = orig_buf;
 909
 910         err = tls_strp_msg_cow(sw_ctx);
 911         if (unlikely(err))
 912                 goto free_buf;
 913
 914         skb = tls_strp_msg(sw_ctx);
 915         rxm = strp_msg(skb);
 916         offset = rxm->offset;
 917
 918         sg_init_table(sg, 1);
 919         sg_set_buf(&sg[0], buf,
 920                    rxm->full_len + TLS_HEADER_SIZE +
 921                    TLS_CIPHER_AES_GCM_128_IV_SIZE);
 922         err = skb_copy_bits(skb, offset, buf,
 923                             TLS_HEADER_SIZE + TLS_CIPHER_AES_GCM_128_IV_SIZE);
 924         if (err)
 925                 goto free_buf;
 926
 927         /* We are interested only in the decrypted data not the auth */
 928         err = decrypt_skb(sk, sg);
 929         if (err != -EBADMSG)
 930                 goto free_buf;
 931         else
 932                 err = 0;
 933
 934         data_len = rxm->full_len - TLS_CIPHER_AES_GCM_128_TAG_SIZE;
 935
 936         if (skb_pagelen(skb) > offset) {
 937                 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 938
 939                 if (skb->decrypted) {
 940                         err = skb_store_bits(skb, offset, buf, copy);
 941                         if (err)
 942                                 goto free_buf;
 943                 }
 944
 945                 offset += copy;
 946                 buf += copy;
 947         }
 948
 949         pos = skb_pagelen(skb);
 950         skb_walk_frags(skb, skb_iter) {
 951                 int frag_pos;
 952
 953                 /* Practically all frags must belong to msg if reencrypt
 954                  * is needed with current strparser and coalescing logic,
 955                  * but strparser may "get optimized", so let's be safe.
 956                  */
 957                 if (pos + skb_iter->len <= offset)
 958                         goto done_with_frag;
 959                 if (pos >= data_len + rxm->offset)
 960                         break;
 961
 962                 frag_pos = offset - pos;
 963                 copy = min_t(int, skb_iter->len - frag_pos,
 964                              data_len + rxm->offset - offset);
 965
 966                 if (skb_iter->decrypted) {
 967                         err = skb_store_bits(skb_iter, frag_pos, buf, copy);
 968                         if (err)
 969                                 goto free_buf;
 970                 }
 971
 972                 offset += copy;
 973                 buf += copy;
 974 done_with_frag:
 975                 pos += skb_iter->len;
 976         }
 977
 978 free_buf:
 979         kfree(orig_buf);
 980         return err;
 981 }
 982
 983 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx)
 984 {
 985         struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
 986         struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
 987         struct sk_buff *skb = tls_strp_msg(sw_ctx);
 988         struct strp_msg *rxm = strp_msg(skb);
 989         int is_decrypted = skb->decrypted;
 990         int is_encrypted = !is_decrypted;
 991         struct sk_buff *skb_iter;
 992
 993         /* Check if all the data is decrypted already */
 994         skb_walk_frags(skb, skb_iter) {
 995                 is_decrypted &= skb_iter->decrypted;
 996                 is_encrypted &= !skb_iter->decrypted;
 997         }
 998
 999         trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
1000                                    tls_ctx->rx.rec_seq, rxm->full_len,
1001                                    is_encrypted, is_decrypted);
1002
1003         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) {
1004                 if (likely(is_encrypted || is_decrypted))
1005                         return is_decrypted;
1006
1007                 /* After tls_device_down disables the offload, the next SKB will
1008                  * likely have initial fragments decrypted, and final ones not
1009                  * decrypted. We need to reencrypt that single SKB.
1010                  */
1011                 return tls_device_reencrypt(sk, sw_ctx);
1012         }
1013
1014         /* Return immediately if the record is either entirely plaintext or
1015          * entirely ciphertext. Otherwise handle reencrypt partially decrypted
1016          * record.
1017          */
1018         if (is_decrypted) {
1019                 ctx->resync_nh_reset = 1;
1020                 return is_decrypted;
1021         }
1022         if (is_encrypted) {
1023                 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
1024                 return 0;
1025         }
1026
1027         ctx->resync_nh_reset = 1;
1028         return tls_device_reencrypt(sk, sw_ctx);
1029 }
1030
1031 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
1032                               struct net_device *netdev)
1033 {
1034         if (sk->sk_destruct != tls_device_sk_destruct) {
1035                 refcount_set(&ctx->refcount, 1);
1036                 dev_hold(netdev);
1037                 ctx->netdev = netdev;
1038                 spin_lock_irq(&tls_device_lock);
1039                 list_add_tail(&ctx->list, &tls_device_list);
1040                 spin_unlock_irq(&tls_device_lock);
1041
1042                 ctx->sk_destruct = sk->sk_destruct;
1043                 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
1044         }
1045 }
1046
1047 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
1048 {
1049         u16 nonce_size, tag_size, iv_size, rec_seq_size, salt_size;
1050         struct tls_context *tls_ctx = tls_get_ctx(sk);
1051         struct tls_prot_info *prot = &tls_ctx->prot_info;
1052         struct tls_record_info *start_marker_record;
1053         struct tls_offload_context_tx *offload_ctx;
1054         struct tls_crypto_info *crypto_info;
1055         struct net_device *netdev;
1056         char *iv, *rec_seq;
1057         struct sk_buff *skb;
1058         __be64 rcd_sn;
1059         int rc;
1060
1061         if (!ctx)
1062                 return -EINVAL;
1063
1064         if (ctx->priv_ctx_tx)
1065                 return -EEXIST;
1066
1067         netdev = get_netdev_for_sock(sk);
1068         if (!netdev) {
1069                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1070                 return -EINVAL;
1071         }
1072
1073         if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1074                 rc = -EOPNOTSUPP;
1075                 goto release_netdev;
1076         }
1077
1078         crypto_info = &ctx->crypto_send.info;
1079         if (crypto_info->version != TLS_1_2_VERSION) {
1080                 rc = -EOPNOTSUPP;
1081                 goto release_netdev;
1082         }
1083
1084         switch (crypto_info->cipher_type) {
1085         case TLS_CIPHER_AES_GCM_128:
1086                 nonce_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1087                 tag_size = TLS_CIPHER_AES_GCM_128_TAG_SIZE;
1088                 iv_size = TLS_CIPHER_AES_GCM_128_IV_SIZE;
1089                 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
1090                 rec_seq_size = TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE;
1091                 salt_size = TLS_CIPHER_AES_GCM_128_SALT_SIZE;
1092                 rec_seq =
1093                  ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
1094                 break;
1095         default:
1096                 rc = -EINVAL;
1097                 goto release_netdev;
1098         }
1099
1100         /* Sanity-check the rec_seq_size for stack allocations */
1101         if (rec_seq_size > TLS_MAX_REC_SEQ_SIZE) {
1102                 rc = -EINVAL;
1103                 goto release_netdev;
1104         }
1105
1106         prot->version = crypto_info->version;
1107         prot->cipher_type = crypto_info->cipher_type;
1108         prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
1109         prot->tag_size = tag_size;
1110         prot->overhead_size = prot->prepend_size + prot->tag_size;
1111         prot->iv_size = iv_size;
1112         prot->salt_size = salt_size;
1113         ctx->tx.iv = kmalloc(iv_size + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
1114                              GFP_KERNEL);
1115         if (!ctx->tx.iv) {
1116                 rc = -ENOMEM;
1117                 goto release_netdev;
1118         }
1119
1120         memcpy(ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv, iv_size);
1121
1122         prot->rec_seq_size = rec_seq_size;
1123         ctx->tx.rec_seq = kmemdup(rec_seq, rec_seq_size, GFP_KERNEL);
1124         if (!ctx->tx.rec_seq) {
1125                 rc = -ENOMEM;
1126                 goto free_iv;
1127         }
1128
1129         start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1130         if (!start_marker_record) {
1131                 rc = -ENOMEM;
1132                 goto free_rec_seq;
1133         }
1134
1135         offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
1136         if (!offload_ctx) {
1137                 rc = -ENOMEM;
1138                 goto free_marker_record;
1139         }
1140
1141         rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1142         if (rc)
1143                 goto free_offload_ctx;
1144
1145         /* start at rec_seq - 1 to account for the start marker record */
1146         memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1147         offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1148
1149         start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1150         start_marker_record->len = 0;
1151         start_marker_record->num_frags = 0;
1152
1153         INIT_LIST_HEAD(&offload_ctx->records_list);
1154         list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1155         spin_lock_init(&offload_ctx->lock);
1156         sg_init_table(offload_ctx->sg_tx_data,
1157                       ARRAY_SIZE(offload_ctx->sg_tx_data));
1158
1159         clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1160         ctx->push_pending_record = tls_device_push_pending_record;
1161
1162         /* TLS offload is greatly simplified if we don't send
1163          * SKBs where only part of the payload needs to be encrypted.
1164          * So mark the last skb in the write queue as end of record.
1165          */
1166         skb = tcp_write_queue_tail(sk);
1167         if (skb)
1168                 TCP_SKB_CB(skb)->eor = 1;
1169
1170         /* Avoid offloading if the device is down
1171          * We don't want to offload new flows after
1172          * the NETDEV_DOWN event
1173          *
1174          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1175          * handler thus protecting from the device going down before
1176          * ctx was added to tls_device_list.
1177          */
1178         down_read(&device_offload_lock);
1179         if (!(netdev->flags & IFF_UP)) {
1180                 rc = -EINVAL;
1181                 goto release_lock;
1182         }
1183
1184         ctx->priv_ctx_tx = offload_ctx;
1185         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1186                                              &ctx->crypto_send.info,
1187                                              tcp_sk(sk)->write_seq);
1188         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1189                                      tcp_sk(sk)->write_seq, rec_seq, rc);
1190         if (rc)
1191                 goto release_lock;
1192
1193         tls_device_attach(ctx, sk, netdev);
1194         up_read(&device_offload_lock);
1195
1196         /* following this assignment tls_is_sk_tx_device_offloaded
1197          * will return true and the context might be accessed
1198          * by the netdev's xmit function.
1199          */
1200         smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1201         dev_put(netdev);
1202
1203         return 0;
1204
1205 release_lock:
1206         up_read(&device_offload_lock);
1207         clean_acked_data_disable(inet_csk(sk));
1208         crypto_free_aead(offload_ctx->aead_send);
1209 free_offload_ctx:
1210         kfree(offload_ctx);
1211         ctx->priv_ctx_tx = NULL;
1212 free_marker_record:
1213         kfree(start_marker_record);
1214 free_rec_seq:
1215         kfree(ctx->tx.rec_seq);
1216 free_iv:
1217         kfree(ctx->tx.iv);
1218 release_netdev:
1219         dev_put(netdev);
1220         return rc;
1221 }
1222
1223 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1224 {
1225         struct tls12_crypto_info_aes_gcm_128 *info;
1226         struct tls_offload_context_rx *context;
1227         struct net_device *netdev;
1228         int rc = 0;
1229
1230         if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1231                 return -EOPNOTSUPP;
1232
1233         netdev = get_netdev_for_sock(sk);
1234         if (!netdev) {
1235                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1236                 return -EINVAL;
1237         }
1238
1239         if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1240                 rc = -EOPNOTSUPP;
1241                 goto release_netdev;
1242         }
1243
1244         /* Avoid offloading if the device is down
1245          * We don't want to offload new flows after
1246          * the NETDEV_DOWN event
1247          *
1248          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1249          * handler thus protecting from the device going down before
1250          * ctx was added to tls_device_list.
1251          */
1252         down_read(&device_offload_lock);
1253         if (!(netdev->flags & IFF_UP)) {
1254                 rc = -EINVAL;
1255                 goto release_lock;
1256         }
1257
1258         context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1259         if (!context) {
1260                 rc = -ENOMEM;
1261                 goto release_lock;
1262         }
1263         context->resync_nh_reset = 1;
1264
1265         ctx->priv_ctx_rx = context;
1266         rc = tls_set_sw_offload(sk, ctx, 0);
1267         if (rc)
1268                 goto release_ctx;
1269
1270         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1271                                              &ctx->crypto_recv.info,
1272                                              tcp_sk(sk)->copied_seq);
1273         info = (void *)&ctx->crypto_recv.info;
1274         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1275                                      tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1276         if (rc)
1277                 goto free_sw_resources;
1278
1279         tls_device_attach(ctx, sk, netdev);
1280         up_read(&device_offload_lock);
1281
1282         dev_put(netdev);
1283
1284         return 0;
1285
1286 free_sw_resources:
1287         up_read(&device_offload_lock);
1288         tls_sw_free_resources_rx(sk);
1289         down_read(&device_offload_lock);
1290 release_ctx:
1291         ctx->priv_ctx_rx = NULL;
1292 release_lock:
1293         up_read(&device_offload_lock);
1294 release_netdev:
1295         dev_put(netdev);
1296         return rc;
1297 }
1298
1299 void tls_device_offload_cleanup_rx(struct sock *sk)
1300 {
1301         struct tls_context *tls_ctx = tls_get_ctx(sk);
1302         struct net_device *netdev;
1303
1304         down_read(&device_offload_lock);
1305         netdev = tls_ctx->netdev;
1306         if (!netdev)
1307                 goto out;
1308
1309         netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1310                                         TLS_OFFLOAD_CTX_DIR_RX);
1311
1312         if (tls_ctx->tx_conf != TLS_HW) {
1313                 dev_put(netdev);
1314                 tls_ctx->netdev = NULL;
1315         } else {
1316                 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
1317         }
1318 out:
1319         up_read(&device_offload_lock);
1320         tls_sw_release_resources_rx(sk);
1321 }
1322
1323 static int tls_device_down(struct net_device *netdev)
1324 {
1325         struct tls_context *ctx, *tmp;
1326         unsigned long flags;
1327         LIST_HEAD(list);
1328
1329         /* Request a write lock to block new offload attempts */
1330         down_write(&device_offload_lock);
1331
1332         spin_lock_irqsave(&tls_device_lock, flags);
1333         list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1334                 if (ctx->netdev != netdev ||
1335                     !refcount_inc_not_zero(&ctx->refcount))
1336                         continue;
1337
1338                 list_move(&ctx->list, &list);
1339         }
1340         spin_unlock_irqrestore(&tls_device_lock, flags);
1341
1342         list_for_each_entry_safe(ctx, tmp, &list, list) {
1343                 /* Stop offloaded TX and switch to the fallback.
1344                  * tls_is_sk_tx_device_offloaded will return false.
1345                  */
1346                 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw);
1347
1348                 /* Stop the RX and TX resync.
1349                  * tls_dev_resync must not be called after tls_dev_del.
1350                  */
1351                 WRITE_ONCE(ctx->netdev, NULL);
1352
1353                 /* Start skipping the RX resync logic completely. */
1354                 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags);
1355
1356                 /* Sync with inflight packets. After this point:
1357                  * TX: no non-encrypted packets will be passed to the driver.
1358                  * RX: resync requests from the driver will be ignored.
1359                  */
1360                 synchronize_net();
1361
1362                 /* Release the offload context on the driver side. */
1363                 if (ctx->tx_conf == TLS_HW)
1364                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1365                                                         TLS_OFFLOAD_CTX_DIR_TX);
1366                 if (ctx->rx_conf == TLS_HW &&
1367                     !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags))
1368                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1369                                                         TLS_OFFLOAD_CTX_DIR_RX);
1370
1371                 dev_put(netdev);
1372
1373                 /* Move the context to a separate list for two reasons:
1374                  * 1. When the context is deallocated, list_del is called.
1375                  * 2. It's no longer an offloaded context, so we don't want to
1376                  *    run offload-specific code on this context.
1377                  */
1378                 spin_lock_irqsave(&tls_device_lock, flags);
1379                 list_move_tail(&ctx->list, &tls_device_down_list);
1380                 spin_unlock_irqrestore(&tls_device_lock, flags);
1381
1382                 /* Device contexts for RX and TX will be freed in on sk_destruct
1383                  * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW.
1384                  * Now release the ref taken above.
1385                  */
1386                 if (refcount_dec_and_test(&ctx->refcount))
1387                         tls_device_free_ctx(ctx);
1388         }
1389
1390         up_write(&device_offload_lock);
1391
1392         flush_work(&tls_device_gc_work);
1393
1394         return NOTIFY_DONE;
1395 }
1396
1397 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1398                          void *ptr)
1399 {
1400         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1401
1402         if (!dev->tlsdev_ops &&
1403             !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1404                 return NOTIFY_DONE;
1405
1406         switch (event) {
1407         case NETDEV_REGISTER:
1408         case NETDEV_FEAT_CHANGE:
1409                 if (netif_is_bond_master(dev))
1410                         return NOTIFY_DONE;
1411                 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1412                     !dev->tlsdev_ops->tls_dev_resync)
1413                         return NOTIFY_BAD;
1414
1415                 if  (dev->tlsdev_ops &&
1416                      dev->tlsdev_ops->tls_dev_add &&
1417                      dev->tlsdev_ops->tls_dev_del)
1418                         return NOTIFY_DONE;
1419                 else
1420                         return NOTIFY_BAD;
1421         case NETDEV_DOWN:
1422                 return tls_device_down(dev);
1423         }
1424         return NOTIFY_DONE;
1425 }
1426
1427 static struct notifier_block tls_dev_notifier = {
1428         .notifier_call  = tls_dev_event,
1429 };
1430
1431 int __init tls_device_init(void)
1432 {
1433         return register_netdevice_notifier(&tls_dev_notifier);
1434 }
1435
1436 void __exit tls_device_cleanup(void)
1437 {
1438         unregister_netdevice_notifier(&tls_dev_notifier);
1439         flush_work(&tls_device_gc_work);
1440         clean_acked_data_flush();
1441 }