net/tls/tls_device.c

   1 /* Copyright (c) 2018, Mellanox Technologies All rights reserved.
   2  *
   3  * This software is available to you under a choice of one of two
   4  * licenses.  You may choose to be licensed under the terms of the GNU
   5  * General Public License (GPL) Version 2, available from the file
   6  * COPYING in the main directory of this source tree, or the
   7  * OpenIB.org BSD license below:
   8  *
   9  *     Redistribution and use in source and binary forms, with or
  10  *     without modification, are permitted provided that the following
  11  *     conditions are met:
  12  *
  13  *      - Redistributions of source code must retain the above
  14  *        copyright notice, this list of conditions and the following
  15  *        disclaimer.
  16  *
  17  *      - Redistributions in binary form must reproduce the above
  18  *        copyright notice, this list of conditions and the following
  19  *        disclaimer in the documentation and/or other materials
  20  *        provided with the distribution.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  26  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  27  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  28  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  29  * SOFTWARE.
  30  */
  31
  32 #include <crypto/aead.h>
  33 #include <linux/highmem.h>
  34 #include <linux/module.h>
  35 #include <linux/netdevice.h>
  36 #include <net/dst.h>
  37 #include <net/inet_connection_sock.h>
  38 #include <net/tcp.h>
  39 #include <net/tls.h>
  40
  41 #include "tls.h"
  42 #include "trace.h"
  43
  44 /* device_offload_lock is used to synchronize tls_dev_add
  45  * against NETDEV_DOWN notifications.
  46  */
  47 static DECLARE_RWSEM(device_offload_lock);
  48
  49 static struct workqueue_struct *destruct_wq __read_mostly;
  50
  51 static LIST_HEAD(tls_device_list);
  52 static LIST_HEAD(tls_device_down_list);
  53 static DEFINE_SPINLOCK(tls_device_lock);
  54
  55 static void tls_device_free_ctx(struct tls_context *ctx)
  56 {
  57         if (ctx->tx_conf == TLS_HW) {
  58                 kfree(tls_offload_ctx_tx(ctx));
  59                 kfree(ctx->tx.rec_seq);
  60                 kfree(ctx->tx.iv);
  61         }
  62
  63         if (ctx->rx_conf == TLS_HW)
  64                 kfree(tls_offload_ctx_rx(ctx));
  65
  66         tls_ctx_free(NULL, ctx);
  67 }
  68
  69 static void tls_device_tx_del_task(struct work_struct *work)
  70 {
  71         struct tls_offload_context_tx *offload_ctx =
  72                 container_of(work, struct tls_offload_context_tx, destruct_work);
  73         struct tls_context *ctx = offload_ctx->ctx;
  74         struct net_device *netdev;
  75
  76         /* Safe, because this is the destroy flow, refcount is 0, so
  77          * tls_device_down can't store this field in parallel.
  78          */
  79         netdev = rcu_dereference_protected(ctx->netdev,
  80                                            !refcount_read(&ctx->refcount));
  81
  82         netdev->tlsdev_ops->tls_dev_del(netdev, ctx, TLS_OFFLOAD_CTX_DIR_TX);
  83         dev_put(netdev);
  84         ctx->netdev = NULL;
  85         tls_device_free_ctx(ctx);
  86 }
  87
  88 static void tls_device_queue_ctx_destruction(struct tls_context *ctx)
  89 {
  90         struct net_device *netdev;
  91         unsigned long flags;
  92         bool async_cleanup;
  93
  94         spin_lock_irqsave(&tls_device_lock, flags);
  95         if (unlikely(!refcount_dec_and_test(&ctx->refcount))) {
  96                 spin_unlock_irqrestore(&tls_device_lock, flags);
  97                 return;
  98         }
  99
 100         list_del(&ctx->list); /* Remove from tls_device_list / tls_device_down_list */
 101
 102         /* Safe, because this is the destroy flow, refcount is 0, so
 103          * tls_device_down can't store this field in parallel.
 104          */
 105         netdev = rcu_dereference_protected(ctx->netdev,
 106                                            !refcount_read(&ctx->refcount));
 107
 108         async_cleanup = netdev && ctx->tx_conf == TLS_HW;
 109         if (async_cleanup) {
 110                 struct tls_offload_context_tx *offload_ctx = tls_offload_ctx_tx(ctx);
 111
 112                 /* queue_work inside the spinlock
 113                  * to make sure tls_device_down waits for that work.
 114                  */
 115                 queue_work(destruct_wq, &offload_ctx->destruct_work);
 116         }
 117         spin_unlock_irqrestore(&tls_device_lock, flags);
 118
 119         if (!async_cleanup)
 120                 tls_device_free_ctx(ctx);
 121 }
 122
 123 /* We assume that the socket is already connected */
 124 static struct net_device *get_netdev_for_sock(struct sock *sk)
 125 {
 126         struct dst_entry *dst = sk_dst_get(sk);
 127         struct net_device *netdev = NULL;
 128
 129         if (likely(dst)) {
 130                 netdev = netdev_sk_get_lowest_dev(dst->dev, sk);
 131                 dev_hold(netdev);
 132         }
 133
 134         dst_release(dst);
 135
 136         return netdev;
 137 }
 138
 139 static void destroy_record(struct tls_record_info *record)
 140 {
 141         int i;
 142
 143         for (i = 0; i < record->num_frags; i++)
 144                 __skb_frag_unref(&record->frags[i], false);
 145         kfree(record);
 146 }
 147
 148 static void delete_all_records(struct tls_offload_context_tx *offload_ctx)
 149 {
 150         struct tls_record_info *info, *temp;
 151
 152         list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) {
 153                 list_del(&info->list);
 154                 destroy_record(info);
 155         }
 156
 157         offload_ctx->retransmit_hint = NULL;
 158 }
 159
 160 static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq)
 161 {
 162         struct tls_context *tls_ctx = tls_get_ctx(sk);
 163         struct tls_record_info *info, *temp;
 164         struct tls_offload_context_tx *ctx;
 165         u64 deleted_records = 0;
 166         unsigned long flags;
 167
 168         if (!tls_ctx)
 169                 return;
 170
 171         ctx = tls_offload_ctx_tx(tls_ctx);
 172
 173         spin_lock_irqsave(&ctx->lock, flags);
 174         info = ctx->retransmit_hint;
 175         if (info && !before(acked_seq, info->end_seq))
 176                 ctx->retransmit_hint = NULL;
 177
 178         list_for_each_entry_safe(info, temp, &ctx->records_list, list) {
 179                 if (before(acked_seq, info->end_seq))
 180                         break;
 181                 list_del(&info->list);
 182
 183                 destroy_record(info);
 184                 deleted_records++;
 185         }
 186
 187         ctx->unacked_record_sn += deleted_records;
 188         spin_unlock_irqrestore(&ctx->lock, flags);
 189 }
 190
 191 /* At this point, there should be no references on this
 192  * socket and no in-flight SKBs associated with this
 193  * socket, so it is safe to free all the resources.
 194  */
 195 void tls_device_sk_destruct(struct sock *sk)
 196 {
 197         struct tls_context *tls_ctx = tls_get_ctx(sk);
 198         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 199
 200         tls_ctx->sk_destruct(sk);
 201
 202         if (tls_ctx->tx_conf == TLS_HW) {
 203                 if (ctx->open_record)
 204                         destroy_record(ctx->open_record);
 205                 delete_all_records(ctx);
 206                 crypto_free_aead(ctx->aead_send);
 207                 clean_acked_data_disable(inet_csk(sk));
 208         }
 209
 210         tls_device_queue_ctx_destruction(tls_ctx);
 211 }
 212 EXPORT_SYMBOL_GPL(tls_device_sk_destruct);
 213
 214 void tls_device_free_resources_tx(struct sock *sk)
 215 {
 216         struct tls_context *tls_ctx = tls_get_ctx(sk);
 217
 218         tls_free_partial_record(sk, tls_ctx);
 219 }
 220
 221 void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq)
 222 {
 223         struct tls_context *tls_ctx = tls_get_ctx(sk);
 224
 225         trace_tls_device_tx_resync_req(sk, got_seq, exp_seq);
 226         WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags));
 227 }
 228 EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request);
 229
 230 static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx,
 231                                  u32 seq)
 232 {
 233         struct net_device *netdev;
 234         struct sk_buff *skb;
 235         int err = 0;
 236         u8 *rcd_sn;
 237
 238         skb = tcp_write_queue_tail(sk);
 239         if (skb)
 240                 TCP_SKB_CB(skb)->eor = 1;
 241
 242         rcd_sn = tls_ctx->tx.rec_seq;
 243
 244         trace_tls_device_tx_resync_send(sk, seq, rcd_sn);
 245         down_read(&device_offload_lock);
 246         netdev = rcu_dereference_protected(tls_ctx->netdev,
 247                                            lockdep_is_held(&device_offload_lock));
 248         if (netdev)
 249                 err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq,
 250                                                          rcd_sn,
 251                                                          TLS_OFFLOAD_CTX_DIR_TX);
 252         up_read(&device_offload_lock);
 253         if (err)
 254                 return;
 255
 256         clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags);
 257 }
 258
 259 static void tls_append_frag(struct tls_record_info *record,
 260                             struct page_frag *pfrag,
 261                             int size)
 262 {
 263         skb_frag_t *frag;
 264
 265         frag = &record->frags[record->num_frags - 1];
 266         if (skb_frag_page(frag) == pfrag->page &&
 267             skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) {
 268                 skb_frag_size_add(frag, size);
 269         } else {
 270                 ++frag;
 271                 __skb_frag_set_page(frag, pfrag->page);
 272                 skb_frag_off_set(frag, pfrag->offset);
 273                 skb_frag_size_set(frag, size);
 274                 ++record->num_frags;
 275                 get_page(pfrag->page);
 276         }
 277
 278         pfrag->offset += size;
 279         record->len += size;
 280 }
 281
 282 static int tls_push_record(struct sock *sk,
 283                            struct tls_context *ctx,
 284                            struct tls_offload_context_tx *offload_ctx,
 285                            struct tls_record_info *record,
 286                            int flags)
 287 {
 288         struct tls_prot_info *prot = &ctx->prot_info;
 289         struct tcp_sock *tp = tcp_sk(sk);
 290         skb_frag_t *frag;
 291         int i;
 292
 293         record->end_seq = tp->write_seq + record->len;
 294         list_add_tail_rcu(&record->list, &offload_ctx->records_list);
 295         offload_ctx->open_record = NULL;
 296
 297         if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
 298                 tls_device_resync_tx(sk, ctx, tp->write_seq);
 299
 300         tls_advance_record_sn(sk, prot, &ctx->tx);
 301
 302         for (i = 0; i < record->num_frags; i++) {
 303                 frag = &record->frags[i];
 304                 sg_unmark_end(&offload_ctx->sg_tx_data[i]);
 305                 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
 306                             skb_frag_size(frag), skb_frag_off(frag));
 307                 sk_mem_charge(sk, skb_frag_size(frag));
 308                 get_page(skb_frag_page(frag));
 309         }
 310         sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
 311
 312         /* all ready, send */
 313         return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
 314 }
 315
 316 static int tls_device_record_close(struct sock *sk,
 317                                    struct tls_context *ctx,
 318                                    struct tls_record_info *record,
 319                                    struct page_frag *pfrag,
 320                                    unsigned char record_type)
 321 {
 322         struct tls_prot_info *prot = &ctx->prot_info;
 323         int ret;
 324
 325         /* append tag
 326          * device will fill in the tag, we just need to append a placeholder
 327          * use socket memory to improve coalescing (re-using a single buffer
 328          * increases frag count)
 329          * if we can't allocate memory now, steal some back from data
 330          */
 331         if (likely(skb_page_frag_refill(prot->tag_size, pfrag,
 332                                         sk->sk_allocation))) {
 333                 ret = 0;
 334                 tls_append_frag(record, pfrag, prot->tag_size);
 335         } else {
 336                 ret = prot->tag_size;
 337                 if (record->len <= prot->overhead_size)
 338                         return -ENOMEM;
 339         }
 340
 341         /* fill prepend */
 342         tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
 343                          record->len - prot->overhead_size,
 344                          record_type);
 345         return ret;
 346 }
 347
 348 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
 349                                  struct page_frag *pfrag,
 350                                  size_t prepend_size)
 351 {
 352         struct tls_record_info *record;
 353         skb_frag_t *frag;
 354
 355         record = kmalloc(sizeof(*record), GFP_KERNEL);
 356         if (!record)
 357                 return -ENOMEM;
 358
 359         frag = &record->frags[0];
 360         __skb_frag_set_page(frag, pfrag->page);
 361         skb_frag_off_set(frag, pfrag->offset);
 362         skb_frag_size_set(frag, prepend_size);
 363
 364         get_page(pfrag->page);
 365         pfrag->offset += prepend_size;
 366
 367         record->num_frags = 1;
 368         record->len = prepend_size;
 369         offload_ctx->open_record = record;
 370         return 0;
 371 }
 372
 373 static int tls_do_allocation(struct sock *sk,
 374                              struct tls_offload_context_tx *offload_ctx,
 375                              struct page_frag *pfrag,
 376                              size_t prepend_size)
 377 {
 378         int ret;
 379
 380         if (!offload_ctx->open_record) {
 381                 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
 382                                                    sk->sk_allocation))) {
 383                         READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
 384                         sk_stream_moderate_sndbuf(sk);
 385                         return -ENOMEM;
 386                 }
 387
 388                 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
 389                 if (ret)
 390                         return ret;
 391
 392                 if (pfrag->size > pfrag->offset)
 393                         return 0;
 394         }
 395
 396         if (!sk_page_frag_refill(sk, pfrag))
 397                 return -ENOMEM;
 398
 399         return 0;
 400 }
 401
 402 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
 403 {
 404         size_t pre_copy, nocache;
 405
 406         pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
 407         if (pre_copy) {
 408                 pre_copy = min(pre_copy, bytes);
 409                 if (copy_from_iter(addr, pre_copy, i) != pre_copy)
 410                         return -EFAULT;
 411                 bytes -= pre_copy;
 412                 addr += pre_copy;
 413         }
 414
 415         nocache = round_down(bytes, SMP_CACHE_BYTES);
 416         if (copy_from_iter_nocache(addr, nocache, i) != nocache)
 417                 return -EFAULT;
 418         bytes -= nocache;
 419         addr += nocache;
 420
 421         if (bytes && copy_from_iter(addr, bytes, i) != bytes)
 422                 return -EFAULT;
 423
 424         return 0;
 425 }
 426
 427 union tls_iter_offset {
 428         struct iov_iter *msg_iter;
 429         int offset;
 430 };
 431
 432 static int tls_push_data(struct sock *sk,
 433                          union tls_iter_offset iter_offset,
 434                          size_t size, int flags,
 435                          unsigned char record_type,
 436                          struct page *zc_page)
 437 {
 438         struct tls_context *tls_ctx = tls_get_ctx(sk);
 439         struct tls_prot_info *prot = &tls_ctx->prot_info;
 440         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 441         struct tls_record_info *record;
 442         int tls_push_record_flags;
 443         struct page_frag *pfrag;
 444         size_t orig_size = size;
 445         u32 max_open_record_len;
 446         bool more = false;
 447         bool done = false;
 448         int copy, rc = 0;
 449         long timeo;
 450
 451         if (flags &
 452             ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST))
 453                 return -EOPNOTSUPP;
 454
 455         if (unlikely(sk->sk_err))
 456                 return -sk->sk_err;
 457
 458         flags |= MSG_SENDPAGE_DECRYPTED;
 459         tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST;
 460
 461         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
 462         if (tls_is_partially_sent_record(tls_ctx)) {
 463                 rc = tls_push_partial_record(sk, tls_ctx, flags);
 464                 if (rc < 0)
 465                         return rc;
 466         }
 467
 468         pfrag = sk_page_frag(sk);
 469
 470         /* TLS_HEADER_SIZE is not counted as part of the TLS record, and
 471          * we need to leave room for an authentication tag.
 472          */
 473         max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
 474                               prot->prepend_size;
 475         do {
 476                 rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
 477                 if (unlikely(rc)) {
 478                         rc = sk_stream_wait_memory(sk, &timeo);
 479                         if (!rc)
 480                                 continue;
 481
 482                         record = ctx->open_record;
 483                         if (!record)
 484                                 break;
 485 handle_error:
 486                         if (record_type != TLS_RECORD_TYPE_DATA) {
 487                                 /* avoid sending partial
 488                                  * record with type !=
 489                                  * application_data
 490                                  */
 491                                 size = orig_size;
 492                                 destroy_record(record);
 493                                 ctx->open_record = NULL;
 494                         } else if (record->len > prot->prepend_size) {
 495                                 goto last_record;
 496                         }
 497
 498                         break;
 499                 }
 500
 501                 record = ctx->open_record;
 502
 503                 copy = min_t(size_t, size, max_open_record_len - record->len);
 504                 if (copy && zc_page) {
 505                         struct page_frag zc_pfrag;
 506
 507                         zc_pfrag.page = zc_page;
 508                         zc_pfrag.offset = iter_offset.offset;
 509                         zc_pfrag.size = copy;
 510                         tls_append_frag(record, &zc_pfrag, copy);
 511
 512                         iter_offset.offset += copy;
 513                 } else if (copy) {
 514                         copy = min_t(size_t, copy, pfrag->size - pfrag->offset);
 515
 516                         rc = tls_device_copy_data(page_address(pfrag->page) +
 517                                                   pfrag->offset, copy,
 518                                                   iter_offset.msg_iter);
 519                         if (rc)
 520                                 goto handle_error;
 521                         tls_append_frag(record, pfrag, copy);
 522                 }
 523
 524                 size -= copy;
 525                 if (!size) {
 526 last_record:
 527                         tls_push_record_flags = flags;
 528                         if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) {
 529                                 more = true;
 530                                 break;
 531                         }
 532
 533                         done = true;
 534                 }
 535
 536                 if (done || record->len >= max_open_record_len ||
 537                     (record->num_frags >= MAX_SKB_FRAGS - 1)) {
 538                         rc = tls_device_record_close(sk, tls_ctx, record,
 539                                                      pfrag, record_type);
 540                         if (rc) {
 541                                 if (rc > 0) {
 542                                         size += rc;
 543                                 } else {
 544                                         size = orig_size;
 545                                         destroy_record(record);
 546                                         ctx->open_record = NULL;
 547                                         break;
 548                                 }
 549                         }
 550
 551                         rc = tls_push_record(sk,
 552                                              tls_ctx,
 553                                              ctx,
 554                                              record,
 555                                              tls_push_record_flags);
 556                         if (rc < 0)
 557                                 break;
 558                 }
 559         } while (!done);
 560
 561         tls_ctx->pending_open_record_frags = more;
 562
 563         if (orig_size - size > 0)
 564                 rc = orig_size - size;
 565
 566         return rc;
 567 }
 568
 569 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 570 {
 571         unsigned char record_type = TLS_RECORD_TYPE_DATA;
 572         struct tls_context *tls_ctx = tls_get_ctx(sk);
 573         union tls_iter_offset iter;
 574         int rc;
 575
 576         mutex_lock(&tls_ctx->tx_lock);
 577         lock_sock(sk);
 578
 579         if (unlikely(msg->msg_controllen)) {
 580                 rc = tls_process_cmsg(sk, msg, &record_type);
 581                 if (rc)
 582                         goto out;
 583         }
 584
 585         iter.msg_iter = &msg->msg_iter;
 586         rc = tls_push_data(sk, iter, size, msg->msg_flags, record_type, NULL);
 587
 588 out:
 589         release_sock(sk);
 590         mutex_unlock(&tls_ctx->tx_lock);
 591         return rc;
 592 }
 593
 594 int tls_device_sendpage(struct sock *sk, struct page *page,
 595                         int offset, size_t size, int flags)
 596 {
 597         struct tls_context *tls_ctx = tls_get_ctx(sk);
 598         union tls_iter_offset iter_offset;
 599         struct iov_iter msg_iter;
 600         char *kaddr;
 601         struct kvec iov;
 602         int rc;
 603
 604         if (flags & MSG_SENDPAGE_NOTLAST)
 605                 flags |= MSG_MORE;
 606
 607         mutex_lock(&tls_ctx->tx_lock);
 608         lock_sock(sk);
 609
 610         if (flags & MSG_OOB) {
 611                 rc = -EOPNOTSUPP;
 612                 goto out;
 613         }
 614
 615         if (tls_ctx->zerocopy_sendfile) {
 616                 iter_offset.offset = offset;
 617                 rc = tls_push_data(sk, iter_offset, size,
 618                                    flags, TLS_RECORD_TYPE_DATA, page);
 619                 goto out;
 620         }
 621
 622         kaddr = kmap(page);
 623         iov.iov_base = kaddr + offset;
 624         iov.iov_len = size;
 625         iov_iter_kvec(&msg_iter, ITER_SOURCE, &iov, 1, size);
 626         iter_offset.msg_iter = &msg_iter;
 627         rc = tls_push_data(sk, iter_offset, size, flags, TLS_RECORD_TYPE_DATA,
 628                            NULL);
 629         kunmap(page);
 630
 631 out:
 632         release_sock(sk);
 633         mutex_unlock(&tls_ctx->tx_lock);
 634         return rc;
 635 }
 636
 637 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
 638                                        u32 seq, u64 *p_record_sn)
 639 {
 640         u64 record_sn = context->hint_record_sn;
 641         struct tls_record_info *info, *last;
 642
 643         info = context->retransmit_hint;
 644         if (!info ||
 645             before(seq, info->end_seq - info->len)) {
 646                 /* if retransmit_hint is irrelevant start
 647                  * from the beginning of the list
 648                  */
 649                 info = list_first_entry_or_null(&context->records_list,
 650                                                 struct tls_record_info, list);
 651                 if (!info)
 652                         return NULL;
 653                 /* send the start_marker record if seq number is before the
 654                  * tls offload start marker sequence number. This record is
 655                  * required to handle TCP packets which are before TLS offload
 656                  * started.
 657                  *  And if it's not start marker, look if this seq number
 658                  * belongs to the list.
 659                  */
 660                 if (likely(!tls_record_is_start_marker(info))) {
 661                         /* we have the first record, get the last record to see
 662                          * if this seq number belongs to the list.
 663                          */
 664                         last = list_last_entry(&context->records_list,
 665                                                struct tls_record_info, list);
 666
 667                         if (!between(seq, tls_record_start_seq(info),
 668                                      last->end_seq))
 669                                 return NULL;
 670                 }
 671                 record_sn = context->unacked_record_sn;
 672         }
 673
 674         /* We just need the _rcu for the READ_ONCE() */
 675         rcu_read_lock();
 676         list_for_each_entry_from_rcu(info, &context->records_list, list) {
 677                 if (before(seq, info->end_seq)) {
 678                         if (!context->retransmit_hint ||
 679                             after(info->end_seq,
 680                                   context->retransmit_hint->end_seq)) {
 681                                 context->hint_record_sn = record_sn;
 682                                 context->retransmit_hint = info;
 683                         }
 684                         *p_record_sn = record_sn;
 685                         goto exit_rcu_unlock;
 686                 }
 687                 record_sn++;
 688         }
 689         info = NULL;
 690
 691 exit_rcu_unlock:
 692         rcu_read_unlock();
 693         return info;
 694 }
 695 EXPORT_SYMBOL(tls_get_record);
 696
 697 static int tls_device_push_pending_record(struct sock *sk, int flags)
 698 {
 699         union tls_iter_offset iter;
 700         struct iov_iter msg_iter;
 701
 702         iov_iter_kvec(&msg_iter, ITER_SOURCE, NULL, 0, 0);
 703         iter.msg_iter = &msg_iter;
 704         return tls_push_data(sk, iter, 0, flags, TLS_RECORD_TYPE_DATA, NULL);
 705 }
 706
 707 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 708 {
 709         if (tls_is_partially_sent_record(ctx)) {
 710                 gfp_t sk_allocation = sk->sk_allocation;
 711
 712                 WARN_ON_ONCE(sk->sk_write_pending);
 713
 714                 sk->sk_allocation = GFP_ATOMIC;
 715                 tls_push_partial_record(sk, ctx,
 716                                         MSG_DONTWAIT | MSG_NOSIGNAL |
 717                                         MSG_SENDPAGE_DECRYPTED);
 718                 sk->sk_allocation = sk_allocation;
 719         }
 720 }
 721
 722 static void tls_device_resync_rx(struct tls_context *tls_ctx,
 723                                  struct sock *sk, u32 seq, u8 *rcd_sn)
 724 {
 725         struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
 726         struct net_device *netdev;
 727
 728         trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
 729         rcu_read_lock();
 730         netdev = rcu_dereference(tls_ctx->netdev);
 731         if (netdev)
 732                 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
 733                                                    TLS_OFFLOAD_CTX_DIR_RX);
 734         rcu_read_unlock();
 735         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
 736 }
 737
 738 static bool
 739 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
 740                            s64 resync_req, u32 *seq, u16 *rcd_delta)
 741 {
 742         u32 is_async = resync_req & RESYNC_REQ_ASYNC;
 743         u32 req_seq = resync_req >> 32;
 744         u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
 745         u16 i;
 746
 747         *rcd_delta = 0;
 748
 749         if (is_async) {
 750                 /* shouldn't get to wraparound:
 751                  * too long in async stage, something bad happened
 752                  */
 753                 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
 754                         return false;
 755
 756                 /* asynchronous stage: log all headers seq such that
 757                  * req_seq <= seq <= end_seq, and wait for real resync request
 758                  */
 759                 if (before(*seq, req_seq))
 760                         return false;
 761                 if (!after(*seq, req_end) &&
 762                     resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
 763                         resync_async->log[resync_async->loglen++] = *seq;
 764
 765                 resync_async->rcd_delta++;
 766
 767                 return false;
 768         }
 769
 770         /* synchronous stage: check against the logged entries and
 771          * proceed to check the next entries if no match was found
 772          */
 773         for (i = 0; i < resync_async->loglen; i++)
 774                 if (req_seq == resync_async->log[i] &&
 775                     atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) {
 776                         *rcd_delta = resync_async->rcd_delta - i;
 777                         *seq = req_seq;
 778                         resync_async->loglen = 0;
 779                         resync_async->rcd_delta = 0;
 780                         return true;
 781                 }
 782
 783         resync_async->loglen = 0;
 784         resync_async->rcd_delta = 0;
 785
 786         if (req_seq == *seq &&
 787             atomic64_try_cmpxchg(&resync_async->req,
 788                                  &resync_req, 0))
 789                 return true;
 790
 791         return false;
 792 }
 793
 794 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
 795 {
 796         struct tls_context *tls_ctx = tls_get_ctx(sk);
 797         struct tls_offload_context_rx *rx_ctx;
 798         u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 799         u32 sock_data, is_req_pending;
 800         struct tls_prot_info *prot;
 801         s64 resync_req;
 802         u16 rcd_delta;
 803         u32 req_seq;
 804
 805         if (tls_ctx->rx_conf != TLS_HW)
 806                 return;
 807         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags)))
 808                 return;
 809
 810         prot = &tls_ctx->prot_info;
 811         rx_ctx = tls_offload_ctx_rx(tls_ctx);
 812         memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 813
 814         switch (rx_ctx->resync_type) {
 815         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
 816                 resync_req = atomic64_read(&rx_ctx->resync_req);
 817                 req_seq = resync_req >> 32;
 818                 seq += TLS_HEADER_SIZE - 1;
 819                 is_req_pending = resync_req;
 820
 821                 if (likely(!is_req_pending) || req_seq != seq ||
 822                     !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
 823                         return;
 824                 break;
 825         case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
 826                 if (likely(!rx_ctx->resync_nh_do_now))
 827                         return;
 828
 829                 /* head of next rec is already in, note that the sock_inq will
 830                  * include the currently parsed message when called from parser
 831                  */
 832                 sock_data = tcp_inq(sk);
 833                 if (sock_data > rcd_len) {
 834                         trace_tls_device_rx_resync_nh_delay(sk, sock_data,
 835                                                             rcd_len);
 836                         return;
 837                 }
 838
 839                 rx_ctx->resync_nh_do_now = 0;
 840                 seq += rcd_len;
 841                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 842                 break;
 843         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
 844                 resync_req = atomic64_read(&rx_ctx->resync_async->req);
 845                 is_req_pending = resync_req;
 846                 if (likely(!is_req_pending))
 847                         return;
 848
 849                 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
 850                                                 resync_req, &seq, &rcd_delta))
 851                         return;
 852                 tls_bigint_subtract(rcd_sn, rcd_delta);
 853                 break;
 854         }
 855
 856         tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
 857 }
 858
 859 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
 860                                            struct tls_offload_context_rx *ctx,
 861                                            struct sock *sk, struct sk_buff *skb)
 862 {
 863         struct strp_msg *rxm;
 864
 865         /* device will request resyncs by itself based on stream scan */
 866         if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
 867                 return;
 868         /* already scheduled */
 869         if (ctx->resync_nh_do_now)
 870                 return;
 871         /* seen decrypted fragments since last fully-failed record */
 872         if (ctx->resync_nh_reset) {
 873                 ctx->resync_nh_reset = 0;
 874                 ctx->resync_nh.decrypted_failed = 1;
 875                 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
 876                 return;
 877         }
 878
 879         if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
 880                 return;
 881
 882         /* doing resync, bump the next target in case it fails */
 883         if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
 884                 ctx->resync_nh.decrypted_tgt *= 2;
 885         else
 886                 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
 887
 888         rxm = strp_msg(skb);
 889
 890         /* head of next rec is already in, parser will sync for us */
 891         if (tcp_inq(sk) > rxm->full_len) {
 892                 trace_tls_device_rx_resync_nh_schedule(sk);
 893                 ctx->resync_nh_do_now = 1;
 894         } else {
 895                 struct tls_prot_info *prot = &tls_ctx->prot_info;
 896                 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 897
 898                 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 899                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 900
 901                 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
 902                                      rcd_sn);
 903         }
 904 }
 905
 906 static int
 907 tls_device_reencrypt(struct sock *sk, struct tls_context *tls_ctx)
 908 {
 909         struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
 910         const struct tls_cipher_size_desc *cipher_sz;
 911         int err, offset, copy, data_len, pos;
 912         struct sk_buff *skb, *skb_iter;
 913         struct scatterlist sg[1];
 914         struct strp_msg *rxm;
 915         char *orig_buf, *buf;
 916
 917         switch (tls_ctx->crypto_recv.info.cipher_type) {
 918         case TLS_CIPHER_AES_GCM_128:
 919         case TLS_CIPHER_AES_GCM_256:
 920                 break;
 921         default:
 922                 return -EINVAL;
 923         }
 924         cipher_sz = &tls_cipher_size_desc[tls_ctx->crypto_recv.info.cipher_type];
 925
 926         rxm = strp_msg(tls_strp_msg(sw_ctx));
 927         orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv,
 928                            sk->sk_allocation);
 929         if (!orig_buf)
 930                 return -ENOMEM;
 931         buf = orig_buf;
 932
 933         err = tls_strp_msg_cow(sw_ctx);
 934         if (unlikely(err))
 935                 goto free_buf;
 936
 937         skb = tls_strp_msg(sw_ctx);
 938         rxm = strp_msg(skb);
 939         offset = rxm->offset;
 940
 941         sg_init_table(sg, 1);
 942         sg_set_buf(&sg[0], buf,
 943                    rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv);
 944         err = skb_copy_bits(skb, offset, buf, TLS_HEADER_SIZE + cipher_sz->iv);
 945         if (err)
 946                 goto free_buf;
 947
 948         /* We are interested only in the decrypted data not the auth */
 949         err = decrypt_skb(sk, sg);
 950         if (err != -EBADMSG)
 951                 goto free_buf;
 952         else
 953                 err = 0;
 954
 955         data_len = rxm->full_len - cipher_sz->tag;
 956
 957         if (skb_pagelen(skb) > offset) {
 958                 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 959
 960                 if (skb->decrypted) {
 961                         err = skb_store_bits(skb, offset, buf, copy);
 962                         if (err)
 963                                 goto free_buf;
 964                 }
 965
 966                 offset += copy;
 967                 buf += copy;
 968         }
 969
 970         pos = skb_pagelen(skb);
 971         skb_walk_frags(skb, skb_iter) {
 972                 int frag_pos;
 973
 974                 /* Practically all frags must belong to msg if reencrypt
 975                  * is needed with current strparser and coalescing logic,
 976                  * but strparser may "get optimized", so let's be safe.
 977                  */
 978                 if (pos + skb_iter->len <= offset)
 979                         goto done_with_frag;
 980                 if (pos >= data_len + rxm->offset)
 981                         break;
 982
 983                 frag_pos = offset - pos;
 984                 copy = min_t(int, skb_iter->len - frag_pos,
 985                              data_len + rxm->offset - offset);
 986
 987                 if (skb_iter->decrypted) {
 988                         err = skb_store_bits(skb_iter, frag_pos, buf, copy);
 989                         if (err)
 990                                 goto free_buf;
 991                 }
 992
 993                 offset += copy;
 994                 buf += copy;
 995 done_with_frag:
 996                 pos += skb_iter->len;
 997         }
 998
 999 free_buf:
1000         kfree(orig_buf);
1001         return err;
1002 }
1003
1004 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx)
1005 {
1006         struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
1007         struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
1008         struct sk_buff *skb = tls_strp_msg(sw_ctx);
1009         struct strp_msg *rxm = strp_msg(skb);
1010         int is_decrypted, is_encrypted;
1011
1012         if (!tls_strp_msg_mixed_decrypted(sw_ctx)) {
1013                 is_decrypted = skb->decrypted;
1014                 is_encrypted = !is_decrypted;
1015         } else {
1016                 is_decrypted = 0;
1017                 is_encrypted = 0;
1018         }
1019
1020         trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
1021                                    tls_ctx->rx.rec_seq, rxm->full_len,
1022                                    is_encrypted, is_decrypted);
1023
1024         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) {
1025                 if (likely(is_encrypted || is_decrypted))
1026                         return is_decrypted;
1027
1028                 /* After tls_device_down disables the offload, the next SKB will
1029                  * likely have initial fragments decrypted, and final ones not
1030                  * decrypted. We need to reencrypt that single SKB.
1031                  */
1032                 return tls_device_reencrypt(sk, tls_ctx);
1033         }
1034
1035         /* Return immediately if the record is either entirely plaintext or
1036          * entirely ciphertext. Otherwise handle reencrypt partially decrypted
1037          * record.
1038          */
1039         if (is_decrypted) {
1040                 ctx->resync_nh_reset = 1;
1041                 return is_decrypted;
1042         }
1043         if (is_encrypted) {
1044                 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
1045                 return 0;
1046         }
1047
1048         ctx->resync_nh_reset = 1;
1049         return tls_device_reencrypt(sk, tls_ctx);
1050 }
1051
1052 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
1053                               struct net_device *netdev)
1054 {
1055         if (sk->sk_destruct != tls_device_sk_destruct) {
1056                 refcount_set(&ctx->refcount, 1);
1057                 dev_hold(netdev);
1058                 RCU_INIT_POINTER(ctx->netdev, netdev);
1059                 spin_lock_irq(&tls_device_lock);
1060                 list_add_tail(&ctx->list, &tls_device_list);
1061                 spin_unlock_irq(&tls_device_lock);
1062
1063                 ctx->sk_destruct = sk->sk_destruct;
1064                 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
1065         }
1066 }
1067
1068 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
1069 {
1070         struct tls_context *tls_ctx = tls_get_ctx(sk);
1071         struct tls_prot_info *prot = &tls_ctx->prot_info;
1072         const struct tls_cipher_size_desc *cipher_sz;
1073         struct tls_record_info *start_marker_record;
1074         struct tls_offload_context_tx *offload_ctx;
1075         struct tls_crypto_info *crypto_info;
1076         struct net_device *netdev;
1077         char *iv, *rec_seq;
1078         struct sk_buff *skb;
1079         __be64 rcd_sn;
1080         int rc;
1081
1082         if (!ctx)
1083                 return -EINVAL;
1084
1085         if (ctx->priv_ctx_tx)
1086                 return -EEXIST;
1087
1088         netdev = get_netdev_for_sock(sk);
1089         if (!netdev) {
1090                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1091                 return -EINVAL;
1092         }
1093
1094         if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1095                 rc = -EOPNOTSUPP;
1096                 goto release_netdev;
1097         }
1098
1099         crypto_info = &ctx->crypto_send.info;
1100         if (crypto_info->version != TLS_1_2_VERSION) {
1101                 rc = -EOPNOTSUPP;
1102                 goto release_netdev;
1103         }
1104
1105         switch (crypto_info->cipher_type) {
1106         case TLS_CIPHER_AES_GCM_128:
1107                 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
1108                 rec_seq =
1109                  ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
1110                 break;
1111         case TLS_CIPHER_AES_GCM_256:
1112                 iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv;
1113                 rec_seq =
1114                  ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq;
1115                 break;
1116         default:
1117                 rc = -EINVAL;
1118                 goto release_netdev;
1119         }
1120         cipher_sz = &tls_cipher_size_desc[crypto_info->cipher_type];
1121
1122         /* Sanity-check the rec_seq_size for stack allocations */
1123         if (cipher_sz->rec_seq > TLS_MAX_REC_SEQ_SIZE) {
1124                 rc = -EINVAL;
1125                 goto release_netdev;
1126         }
1127
1128         prot->version = crypto_info->version;
1129         prot->cipher_type = crypto_info->cipher_type;
1130         prot->prepend_size = TLS_HEADER_SIZE + cipher_sz->iv;
1131         prot->tag_size = cipher_sz->tag;
1132         prot->overhead_size = prot->prepend_size + prot->tag_size;
1133         prot->iv_size = cipher_sz->iv;
1134         prot->salt_size = cipher_sz->salt;
1135         ctx->tx.iv = kmalloc(cipher_sz->iv + cipher_sz->salt, GFP_KERNEL);
1136         if (!ctx->tx.iv) {
1137                 rc = -ENOMEM;
1138                 goto release_netdev;
1139         }
1140
1141         memcpy(ctx->tx.iv + cipher_sz->salt, iv, cipher_sz->iv);
1142
1143         prot->rec_seq_size = cipher_sz->rec_seq;
1144         ctx->tx.rec_seq = kmemdup(rec_seq, cipher_sz->rec_seq, GFP_KERNEL);
1145         if (!ctx->tx.rec_seq) {
1146                 rc = -ENOMEM;
1147                 goto free_iv;
1148         }
1149
1150         start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1151         if (!start_marker_record) {
1152                 rc = -ENOMEM;
1153                 goto free_rec_seq;
1154         }
1155
1156         offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
1157         if (!offload_ctx) {
1158                 rc = -ENOMEM;
1159                 goto free_marker_record;
1160         }
1161
1162         rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1163         if (rc)
1164                 goto free_offload_ctx;
1165
1166         /* start at rec_seq - 1 to account for the start marker record */
1167         memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1168         offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1169
1170         start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1171         start_marker_record->len = 0;
1172         start_marker_record->num_frags = 0;
1173
1174         INIT_WORK(&offload_ctx->destruct_work, tls_device_tx_del_task);
1175         offload_ctx->ctx = ctx;
1176
1177         INIT_LIST_HEAD(&offload_ctx->records_list);
1178         list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1179         spin_lock_init(&offload_ctx->lock);
1180         sg_init_table(offload_ctx->sg_tx_data,
1181                       ARRAY_SIZE(offload_ctx->sg_tx_data));
1182
1183         clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1184         ctx->push_pending_record = tls_device_push_pending_record;
1185
1186         /* TLS offload is greatly simplified if we don't send
1187          * SKBs where only part of the payload needs to be encrypted.
1188          * So mark the last skb in the write queue as end of record.
1189          */
1190         skb = tcp_write_queue_tail(sk);
1191         if (skb)
1192                 TCP_SKB_CB(skb)->eor = 1;
1193
1194         /* Avoid offloading if the device is down
1195          * We don't want to offload new flows after
1196          * the NETDEV_DOWN event
1197          *
1198          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1199          * handler thus protecting from the device going down before
1200          * ctx was added to tls_device_list.
1201          */
1202         down_read(&device_offload_lock);
1203         if (!(netdev->flags & IFF_UP)) {
1204                 rc = -EINVAL;
1205                 goto release_lock;
1206         }
1207
1208         ctx->priv_ctx_tx = offload_ctx;
1209         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1210                                              &ctx->crypto_send.info,
1211                                              tcp_sk(sk)->write_seq);
1212         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1213                                      tcp_sk(sk)->write_seq, rec_seq, rc);
1214         if (rc)
1215                 goto release_lock;
1216
1217         tls_device_attach(ctx, sk, netdev);
1218         up_read(&device_offload_lock);
1219
1220         /* following this assignment tls_is_sk_tx_device_offloaded
1221          * will return true and the context might be accessed
1222          * by the netdev's xmit function.
1223          */
1224         smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1225         dev_put(netdev);
1226
1227         return 0;
1228
1229 release_lock:
1230         up_read(&device_offload_lock);
1231         clean_acked_data_disable(inet_csk(sk));
1232         crypto_free_aead(offload_ctx->aead_send);
1233 free_offload_ctx:
1234         kfree(offload_ctx);
1235         ctx->priv_ctx_tx = NULL;
1236 free_marker_record:
1237         kfree(start_marker_record);
1238 free_rec_seq:
1239         kfree(ctx->tx.rec_seq);
1240 free_iv:
1241         kfree(ctx->tx.iv);
1242 release_netdev:
1243         dev_put(netdev);
1244         return rc;
1245 }
1246
1247 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1248 {
1249         struct tls12_crypto_info_aes_gcm_128 *info;
1250         struct tls_offload_context_rx *context;
1251         struct net_device *netdev;
1252         int rc = 0;
1253
1254         if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1255                 return -EOPNOTSUPP;
1256
1257         netdev = get_netdev_for_sock(sk);
1258         if (!netdev) {
1259                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1260                 return -EINVAL;
1261         }
1262
1263         if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1264                 rc = -EOPNOTSUPP;
1265                 goto release_netdev;
1266         }
1267
1268         /* Avoid offloading if the device is down
1269          * We don't want to offload new flows after
1270          * the NETDEV_DOWN event
1271          *
1272          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1273          * handler thus protecting from the device going down before
1274          * ctx was added to tls_device_list.
1275          */
1276         down_read(&device_offload_lock);
1277         if (!(netdev->flags & IFF_UP)) {
1278                 rc = -EINVAL;
1279                 goto release_lock;
1280         }
1281
1282         context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1283         if (!context) {
1284                 rc = -ENOMEM;
1285                 goto release_lock;
1286         }
1287         context->resync_nh_reset = 1;
1288
1289         ctx->priv_ctx_rx = context;
1290         rc = tls_set_sw_offload(sk, ctx, 0);
1291         if (rc)
1292                 goto release_ctx;
1293
1294         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1295                                              &ctx->crypto_recv.info,
1296                                              tcp_sk(sk)->copied_seq);
1297         info = (void *)&ctx->crypto_recv.info;
1298         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1299                                      tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1300         if (rc)
1301                 goto free_sw_resources;
1302
1303         tls_device_attach(ctx, sk, netdev);
1304         up_read(&device_offload_lock);
1305
1306         dev_put(netdev);
1307
1308         return 0;
1309
1310 free_sw_resources:
1311         up_read(&device_offload_lock);
1312         tls_sw_free_resources_rx(sk);
1313         down_read(&device_offload_lock);
1314 release_ctx:
1315         ctx->priv_ctx_rx = NULL;
1316 release_lock:
1317         up_read(&device_offload_lock);
1318 release_netdev:
1319         dev_put(netdev);
1320         return rc;
1321 }
1322
1323 void tls_device_offload_cleanup_rx(struct sock *sk)
1324 {
1325         struct tls_context *tls_ctx = tls_get_ctx(sk);
1326         struct net_device *netdev;
1327
1328         down_read(&device_offload_lock);
1329         netdev = rcu_dereference_protected(tls_ctx->netdev,
1330                                            lockdep_is_held(&device_offload_lock));
1331         if (!netdev)
1332                 goto out;
1333
1334         netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1335                                         TLS_OFFLOAD_CTX_DIR_RX);
1336
1337         if (tls_ctx->tx_conf != TLS_HW) {
1338                 dev_put(netdev);
1339                 rcu_assign_pointer(tls_ctx->netdev, NULL);
1340         } else {
1341                 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
1342         }
1343 out:
1344         up_read(&device_offload_lock);
1345         tls_sw_release_resources_rx(sk);
1346 }
1347
1348 static int tls_device_down(struct net_device *netdev)
1349 {
1350         struct tls_context *ctx, *tmp;
1351         unsigned long flags;
1352         LIST_HEAD(list);
1353
1354         /* Request a write lock to block new offload attempts */
1355         down_write(&device_offload_lock);
1356
1357         spin_lock_irqsave(&tls_device_lock, flags);
1358         list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1359                 struct net_device *ctx_netdev =
1360                         rcu_dereference_protected(ctx->netdev,
1361                                                   lockdep_is_held(&device_offload_lock));
1362
1363                 if (ctx_netdev != netdev ||
1364                     !refcount_inc_not_zero(&ctx->refcount))
1365                         continue;
1366
1367                 list_move(&ctx->list, &list);
1368         }
1369         spin_unlock_irqrestore(&tls_device_lock, flags);
1370
1371         list_for_each_entry_safe(ctx, tmp, &list, list) {
1372                 /* Stop offloaded TX and switch to the fallback.
1373                  * tls_is_sk_tx_device_offloaded will return false.
1374                  */
1375                 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw);
1376
1377                 /* Stop the RX and TX resync.
1378                  * tls_dev_resync must not be called after tls_dev_del.
1379                  */
1380                 rcu_assign_pointer(ctx->netdev, NULL);
1381
1382                 /* Start skipping the RX resync logic completely. */
1383                 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags);
1384
1385                 /* Sync with inflight packets. After this point:
1386                  * TX: no non-encrypted packets will be passed to the driver.
1387                  * RX: resync requests from the driver will be ignored.
1388                  */
1389                 synchronize_net();
1390
1391                 /* Release the offload context on the driver side. */
1392                 if (ctx->tx_conf == TLS_HW)
1393                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1394                                                         TLS_OFFLOAD_CTX_DIR_TX);
1395                 if (ctx->rx_conf == TLS_HW &&
1396                     !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags))
1397                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1398                                                         TLS_OFFLOAD_CTX_DIR_RX);
1399
1400                 dev_put(netdev);
1401
1402                 /* Move the context to a separate list for two reasons:
1403                  * 1. When the context is deallocated, list_del is called.
1404                  * 2. It's no longer an offloaded context, so we don't want to
1405                  *    run offload-specific code on this context.
1406                  */
1407                 spin_lock_irqsave(&tls_device_lock, flags);
1408                 list_move_tail(&ctx->list, &tls_device_down_list);
1409                 spin_unlock_irqrestore(&tls_device_lock, flags);
1410
1411                 /* Device contexts for RX and TX will be freed in on sk_destruct
1412                  * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW.
1413                  * Now release the ref taken above.
1414                  */
1415                 if (refcount_dec_and_test(&ctx->refcount)) {
1416                         /* sk_destruct ran after tls_device_down took a ref, and
1417                          * it returned early. Complete the destruction here.
1418                          */
1419                         list_del(&ctx->list);
1420                         tls_device_free_ctx(ctx);
1421                 }
1422         }
1423
1424         up_write(&device_offload_lock);
1425
1426         flush_workqueue(destruct_wq);
1427
1428         return NOTIFY_DONE;
1429 }
1430
1431 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1432                          void *ptr)
1433 {
1434         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1435
1436         if (!dev->tlsdev_ops &&
1437             !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1438                 return NOTIFY_DONE;
1439
1440         switch (event) {
1441         case NETDEV_REGISTER:
1442         case NETDEV_FEAT_CHANGE:
1443                 if (netif_is_bond_master(dev))
1444                         return NOTIFY_DONE;
1445                 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1446                     !dev->tlsdev_ops->tls_dev_resync)
1447                         return NOTIFY_BAD;
1448
1449                 if  (dev->tlsdev_ops &&
1450                      dev->tlsdev_ops->tls_dev_add &&
1451                      dev->tlsdev_ops->tls_dev_del)
1452                         return NOTIFY_DONE;
1453                 else
1454                         return NOTIFY_BAD;
1455         case NETDEV_DOWN:
1456                 return tls_device_down(dev);
1457         }
1458         return NOTIFY_DONE;
1459 }
1460
1461 static struct notifier_block tls_dev_notifier = {
1462         .notifier_call  = tls_dev_event,
1463 };
1464
1465 int __init tls_device_init(void)
1466 {
1467         int err;
1468
1469         destruct_wq = alloc_workqueue("ktls_device_destruct", 0, 0);
1470         if (!destruct_wq)
1471                 return -ENOMEM;
1472
1473         err = register_netdevice_notifier(&tls_dev_notifier);
1474         if (err)
1475                 destroy_workqueue(destruct_wq);
1476
1477         return err;
1478 }
1479
1480 void __exit tls_device_cleanup(void)
1481 {
1482         unregister_netdevice_notifier(&tls_dev_notifier);
1483         destroy_workqueue(destruct_wq);
1484         clean_acked_data_flush();
1485 }