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_fill_page_desc(frag, pfrag->page, pfrag->offset,
 272                                         size);
 273                 ++record->num_frags;
 274                 get_page(pfrag->page);
 275         }
 276
 277         pfrag->offset += size;
 278         record->len += size;
 279 }
 280
 281 static int tls_push_record(struct sock *sk,
 282                            struct tls_context *ctx,
 283                            struct tls_offload_context_tx *offload_ctx,
 284                            struct tls_record_info *record,
 285                            int flags)
 286 {
 287         struct tls_prot_info *prot = &ctx->prot_info;
 288         struct tcp_sock *tp = tcp_sk(sk);
 289         skb_frag_t *frag;
 290         int i;
 291
 292         record->end_seq = tp->write_seq + record->len;
 293         list_add_tail_rcu(&record->list, &offload_ctx->records_list);
 294         offload_ctx->open_record = NULL;
 295
 296         if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags))
 297                 tls_device_resync_tx(sk, ctx, tp->write_seq);
 298
 299         tls_advance_record_sn(sk, prot, &ctx->tx);
 300
 301         for (i = 0; i < record->num_frags; i++) {
 302                 frag = &record->frags[i];
 303                 sg_unmark_end(&offload_ctx->sg_tx_data[i]);
 304                 sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag),
 305                             skb_frag_size(frag), skb_frag_off(frag));
 306                 sk_mem_charge(sk, skb_frag_size(frag));
 307                 get_page(skb_frag_page(frag));
 308         }
 309         sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]);
 310
 311         /* all ready, send */
 312         return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags);
 313 }
 314
 315 static int tls_device_record_close(struct sock *sk,
 316                                    struct tls_context *ctx,
 317                                    struct tls_record_info *record,
 318                                    struct page_frag *pfrag,
 319                                    unsigned char record_type)
 320 {
 321         struct tls_prot_info *prot = &ctx->prot_info;
 322         int ret;
 323
 324         /* append tag
 325          * device will fill in the tag, we just need to append a placeholder
 326          * use socket memory to improve coalescing (re-using a single buffer
 327          * increases frag count)
 328          * if we can't allocate memory now, steal some back from data
 329          */
 330         if (likely(skb_page_frag_refill(prot->tag_size, pfrag,
 331                                         sk->sk_allocation))) {
 332                 ret = 0;
 333                 tls_append_frag(record, pfrag, prot->tag_size);
 334         } else {
 335                 ret = prot->tag_size;
 336                 if (record->len <= prot->overhead_size)
 337                         return -ENOMEM;
 338         }
 339
 340         /* fill prepend */
 341         tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]),
 342                          record->len - prot->overhead_size,
 343                          record_type);
 344         return ret;
 345 }
 346
 347 static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx,
 348                                  struct page_frag *pfrag,
 349                                  size_t prepend_size)
 350 {
 351         struct tls_record_info *record;
 352         skb_frag_t *frag;
 353
 354         record = kmalloc(sizeof(*record), GFP_KERNEL);
 355         if (!record)
 356                 return -ENOMEM;
 357
 358         frag = &record->frags[0];
 359         skb_frag_fill_page_desc(frag, pfrag->page, pfrag->offset,
 360                                 prepend_size);
 361
 362         get_page(pfrag->page);
 363         pfrag->offset += prepend_size;
 364
 365         record->num_frags = 1;
 366         record->len = prepend_size;
 367         offload_ctx->open_record = record;
 368         return 0;
 369 }
 370
 371 static int tls_do_allocation(struct sock *sk,
 372                              struct tls_offload_context_tx *offload_ctx,
 373                              struct page_frag *pfrag,
 374                              size_t prepend_size)
 375 {
 376         int ret;
 377
 378         if (!offload_ctx->open_record) {
 379                 if (unlikely(!skb_page_frag_refill(prepend_size, pfrag,
 380                                                    sk->sk_allocation))) {
 381                         READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk);
 382                         sk_stream_moderate_sndbuf(sk);
 383                         return -ENOMEM;
 384                 }
 385
 386                 ret = tls_create_new_record(offload_ctx, pfrag, prepend_size);
 387                 if (ret)
 388                         return ret;
 389
 390                 if (pfrag->size > pfrag->offset)
 391                         return 0;
 392         }
 393
 394         if (!sk_page_frag_refill(sk, pfrag))
 395                 return -ENOMEM;
 396
 397         return 0;
 398 }
 399
 400 static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i)
 401 {
 402         size_t pre_copy, nocache;
 403
 404         pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1);
 405         if (pre_copy) {
 406                 pre_copy = min(pre_copy, bytes);
 407                 if (copy_from_iter(addr, pre_copy, i) != pre_copy)
 408                         return -EFAULT;
 409                 bytes -= pre_copy;
 410                 addr += pre_copy;
 411         }
 412
 413         nocache = round_down(bytes, SMP_CACHE_BYTES);
 414         if (copy_from_iter_nocache(addr, nocache, i) != nocache)
 415                 return -EFAULT;
 416         bytes -= nocache;
 417         addr += nocache;
 418
 419         if (bytes && copy_from_iter(addr, bytes, i) != bytes)
 420                 return -EFAULT;
 421
 422         return 0;
 423 }
 424
 425 static int tls_push_data(struct sock *sk,
 426                          struct iov_iter *iter,
 427                          size_t size, int flags,
 428                          unsigned char record_type)
 429 {
 430         struct tls_context *tls_ctx = tls_get_ctx(sk);
 431         struct tls_prot_info *prot = &tls_ctx->prot_info;
 432         struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx);
 433         struct tls_record_info *record;
 434         int tls_push_record_flags;
 435         struct page_frag *pfrag;
 436         size_t orig_size = size;
 437         u32 max_open_record_len;
 438         bool more = false;
 439         bool done = false;
 440         int copy, rc = 0;
 441         long timeo;
 442
 443         if (flags &
 444             ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST |
 445               MSG_SPLICE_PAGES))
 446                 return -EOPNOTSUPP;
 447
 448         if (unlikely(sk->sk_err))
 449                 return -sk->sk_err;
 450
 451         flags |= MSG_SENDPAGE_DECRYPTED;
 452         tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST;
 453
 454         timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
 455         if (tls_is_partially_sent_record(tls_ctx)) {
 456                 rc = tls_push_partial_record(sk, tls_ctx, flags);
 457                 if (rc < 0)
 458                         return rc;
 459         }
 460
 461         pfrag = sk_page_frag(sk);
 462
 463         /* TLS_HEADER_SIZE is not counted as part of the TLS record, and
 464          * we need to leave room for an authentication tag.
 465          */
 466         max_open_record_len = TLS_MAX_PAYLOAD_SIZE +
 467                               prot->prepend_size;
 468         do {
 469                 rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size);
 470                 if (unlikely(rc)) {
 471                         rc = sk_stream_wait_memory(sk, &timeo);
 472                         if (!rc)
 473                                 continue;
 474
 475                         record = ctx->open_record;
 476                         if (!record)
 477                                 break;
 478 handle_error:
 479                         if (record_type != TLS_RECORD_TYPE_DATA) {
 480                                 /* avoid sending partial
 481                                  * record with type !=
 482                                  * application_data
 483                                  */
 484                                 size = orig_size;
 485                                 destroy_record(record);
 486                                 ctx->open_record = NULL;
 487                         } else if (record->len > prot->prepend_size) {
 488                                 goto last_record;
 489                         }
 490
 491                         break;
 492                 }
 493
 494                 record = ctx->open_record;
 495
 496                 copy = min_t(size_t, size, max_open_record_len - record->len);
 497                 if (copy && (flags & MSG_SPLICE_PAGES)) {
 498                         struct page_frag zc_pfrag;
 499                         struct page **pages = &zc_pfrag.page;
 500                         size_t off;
 501
 502                         rc = iov_iter_extract_pages(iter, &pages,
 503                                                     copy, 1, 0, &off);
 504                         if (rc <= 0) {
 505                                 if (rc == 0)
 506                                         rc = -EIO;
 507                                 goto handle_error;
 508                         }
 509                         copy = rc;
 510
 511                         if (WARN_ON_ONCE(!sendpage_ok(zc_pfrag.page))) {
 512                                 iov_iter_revert(iter, copy);
 513                                 rc = -EIO;
 514                                 goto handle_error;
 515                         }
 516
 517                         zc_pfrag.offset = off;
 518                         zc_pfrag.size = copy;
 519                         tls_append_frag(record, &zc_pfrag, copy);
 520                 } else if (copy) {
 521                         copy = min_t(size_t, copy, pfrag->size - pfrag->offset);
 522
 523                         rc = tls_device_copy_data(page_address(pfrag->page) +
 524                                                   pfrag->offset, copy,
 525                                                   iter);
 526                         if (rc)
 527                                 goto handle_error;
 528                         tls_append_frag(record, pfrag, copy);
 529                 }
 530
 531                 size -= copy;
 532                 if (!size) {
 533 last_record:
 534                         tls_push_record_flags = flags;
 535                         if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) {
 536                                 more = true;
 537                                 break;
 538                         }
 539
 540                         done = true;
 541                 }
 542
 543                 if (done || record->len >= max_open_record_len ||
 544                     (record->num_frags >= MAX_SKB_FRAGS - 1)) {
 545                         rc = tls_device_record_close(sk, tls_ctx, record,
 546                                                      pfrag, record_type);
 547                         if (rc) {
 548                                 if (rc > 0) {
 549                                         size += rc;
 550                                 } else {
 551                                         size = orig_size;
 552                                         destroy_record(record);
 553                                         ctx->open_record = NULL;
 554                                         break;
 555                                 }
 556                         }
 557
 558                         rc = tls_push_record(sk,
 559                                              tls_ctx,
 560                                              ctx,
 561                                              record,
 562                                              tls_push_record_flags);
 563                         if (rc < 0)
 564                                 break;
 565                 }
 566         } while (!done);
 567
 568         tls_ctx->pending_open_record_frags = more;
 569
 570         if (orig_size - size > 0)
 571                 rc = orig_size - size;
 572
 573         return rc;
 574 }
 575
 576 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
 577 {
 578         unsigned char record_type = TLS_RECORD_TYPE_DATA;
 579         struct tls_context *tls_ctx = tls_get_ctx(sk);
 580         int rc;
 581
 582         if (!tls_ctx->zerocopy_sendfile)
 583                 msg->msg_flags &= ~MSG_SPLICE_PAGES;
 584
 585         mutex_lock(&tls_ctx->tx_lock);
 586         lock_sock(sk);
 587
 588         if (unlikely(msg->msg_controllen)) {
 589                 rc = tls_process_cmsg(sk, msg, &record_type);
 590                 if (rc)
 591                         goto out;
 592         }
 593
 594         rc = tls_push_data(sk, &msg->msg_iter, size, msg->msg_flags,
 595                            record_type);
 596
 597 out:
 598         release_sock(sk);
 599         mutex_unlock(&tls_ctx->tx_lock);
 600         return rc;
 601 }
 602
 603 void tls_device_splice_eof(struct socket *sock)
 604 {
 605         struct sock *sk = sock->sk;
 606         struct tls_context *tls_ctx = tls_get_ctx(sk);
 607         struct iov_iter iter = {};
 608
 609         if (!tls_is_partially_sent_record(tls_ctx))
 610                 return;
 611
 612         mutex_lock(&tls_ctx->tx_lock);
 613         lock_sock(sk);
 614
 615         if (tls_is_partially_sent_record(tls_ctx)) {
 616                 iov_iter_bvec(&iter, ITER_SOURCE, NULL, 0, 0);
 617                 tls_push_data(sk, &iter, 0, 0, TLS_RECORD_TYPE_DATA);
 618         }
 619
 620         release_sock(sk);
 621         mutex_unlock(&tls_ctx->tx_lock);
 622 }
 623
 624 int tls_device_sendpage(struct sock *sk, struct page *page,
 625                         int offset, size_t size, int flags)
 626 {
 627         struct bio_vec bvec;
 628         struct msghdr msg = { .msg_flags = flags | MSG_SPLICE_PAGES, };
 629
 630         if (flags & MSG_SENDPAGE_NOTLAST)
 631                 msg.msg_flags |= MSG_MORE;
 632
 633         if (flags & MSG_OOB)
 634                 return -EOPNOTSUPP;
 635
 636         bvec_set_page(&bvec, page, size, offset);
 637         iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size);
 638         return tls_device_sendmsg(sk, &msg, size);
 639 }
 640
 641 struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context,
 642                                        u32 seq, u64 *p_record_sn)
 643 {
 644         u64 record_sn = context->hint_record_sn;
 645         struct tls_record_info *info, *last;
 646
 647         info = context->retransmit_hint;
 648         if (!info ||
 649             before(seq, info->end_seq - info->len)) {
 650                 /* if retransmit_hint is irrelevant start
 651                  * from the beginning of the list
 652                  */
 653                 info = list_first_entry_or_null(&context->records_list,
 654                                                 struct tls_record_info, list);
 655                 if (!info)
 656                         return NULL;
 657                 /* send the start_marker record if seq number is before the
 658                  * tls offload start marker sequence number. This record is
 659                  * required to handle TCP packets which are before TLS offload
 660                  * started.
 661                  *  And if it's not start marker, look if this seq number
 662                  * belongs to the list.
 663                  */
 664                 if (likely(!tls_record_is_start_marker(info))) {
 665                         /* we have the first record, get the last record to see
 666                          * if this seq number belongs to the list.
 667                          */
 668                         last = list_last_entry(&context->records_list,
 669                                                struct tls_record_info, list);
 670
 671                         if (!between(seq, tls_record_start_seq(info),
 672                                      last->end_seq))
 673                                 return NULL;
 674                 }
 675                 record_sn = context->unacked_record_sn;
 676         }
 677
 678         /* We just need the _rcu for the READ_ONCE() */
 679         rcu_read_lock();
 680         list_for_each_entry_from_rcu(info, &context->records_list, list) {
 681                 if (before(seq, info->end_seq)) {
 682                         if (!context->retransmit_hint ||
 683                             after(info->end_seq,
 684                                   context->retransmit_hint->end_seq)) {
 685                                 context->hint_record_sn = record_sn;
 686                                 context->retransmit_hint = info;
 687                         }
 688                         *p_record_sn = record_sn;
 689                         goto exit_rcu_unlock;
 690                 }
 691                 record_sn++;
 692         }
 693         info = NULL;
 694
 695 exit_rcu_unlock:
 696         rcu_read_unlock();
 697         return info;
 698 }
 699 EXPORT_SYMBOL(tls_get_record);
 700
 701 static int tls_device_push_pending_record(struct sock *sk, int flags)
 702 {
 703         struct iov_iter iter;
 704
 705         iov_iter_kvec(&iter, ITER_SOURCE, NULL, 0, 0);
 706         return tls_push_data(sk, &iter, 0, flags, TLS_RECORD_TYPE_DATA);
 707 }
 708
 709 void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 710 {
 711         if (tls_is_partially_sent_record(ctx)) {
 712                 gfp_t sk_allocation = sk->sk_allocation;
 713
 714                 WARN_ON_ONCE(sk->sk_write_pending);
 715
 716                 sk->sk_allocation = GFP_ATOMIC;
 717                 tls_push_partial_record(sk, ctx,
 718                                         MSG_DONTWAIT | MSG_NOSIGNAL |
 719                                         MSG_SENDPAGE_DECRYPTED);
 720                 sk->sk_allocation = sk_allocation;
 721         }
 722 }
 723
 724 static void tls_device_resync_rx(struct tls_context *tls_ctx,
 725                                  struct sock *sk, u32 seq, u8 *rcd_sn)
 726 {
 727         struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx);
 728         struct net_device *netdev;
 729
 730         trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type);
 731         rcu_read_lock();
 732         netdev = rcu_dereference(tls_ctx->netdev);
 733         if (netdev)
 734                 netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn,
 735                                                    TLS_OFFLOAD_CTX_DIR_RX);
 736         rcu_read_unlock();
 737         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC);
 738 }
 739
 740 static bool
 741 tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async,
 742                            s64 resync_req, u32 *seq, u16 *rcd_delta)
 743 {
 744         u32 is_async = resync_req & RESYNC_REQ_ASYNC;
 745         u32 req_seq = resync_req >> 32;
 746         u32 req_end = req_seq + ((resync_req >> 16) & 0xffff);
 747         u16 i;
 748
 749         *rcd_delta = 0;
 750
 751         if (is_async) {
 752                 /* shouldn't get to wraparound:
 753                  * too long in async stage, something bad happened
 754                  */
 755                 if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX))
 756                         return false;
 757
 758                 /* asynchronous stage: log all headers seq such that
 759                  * req_seq <= seq <= end_seq, and wait for real resync request
 760                  */
 761                 if (before(*seq, req_seq))
 762                         return false;
 763                 if (!after(*seq, req_end) &&
 764                     resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX)
 765                         resync_async->log[resync_async->loglen++] = *seq;
 766
 767                 resync_async->rcd_delta++;
 768
 769                 return false;
 770         }
 771
 772         /* synchronous stage: check against the logged entries and
 773          * proceed to check the next entries if no match was found
 774          */
 775         for (i = 0; i < resync_async->loglen; i++)
 776                 if (req_seq == resync_async->log[i] &&
 777                     atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) {
 778                         *rcd_delta = resync_async->rcd_delta - i;
 779                         *seq = req_seq;
 780                         resync_async->loglen = 0;
 781                         resync_async->rcd_delta = 0;
 782                         return true;
 783                 }
 784
 785         resync_async->loglen = 0;
 786         resync_async->rcd_delta = 0;
 787
 788         if (req_seq == *seq &&
 789             atomic64_try_cmpxchg(&resync_async->req,
 790                                  &resync_req, 0))
 791                 return true;
 792
 793         return false;
 794 }
 795
 796 void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq)
 797 {
 798         struct tls_context *tls_ctx = tls_get_ctx(sk);
 799         struct tls_offload_context_rx *rx_ctx;
 800         u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 801         u32 sock_data, is_req_pending;
 802         struct tls_prot_info *prot;
 803         s64 resync_req;
 804         u16 rcd_delta;
 805         u32 req_seq;
 806
 807         if (tls_ctx->rx_conf != TLS_HW)
 808                 return;
 809         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags)))
 810                 return;
 811
 812         prot = &tls_ctx->prot_info;
 813         rx_ctx = tls_offload_ctx_rx(tls_ctx);
 814         memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 815
 816         switch (rx_ctx->resync_type) {
 817         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ:
 818                 resync_req = atomic64_read(&rx_ctx->resync_req);
 819                 req_seq = resync_req >> 32;
 820                 seq += TLS_HEADER_SIZE - 1;
 821                 is_req_pending = resync_req;
 822
 823                 if (likely(!is_req_pending) || req_seq != seq ||
 824                     !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
 825                         return;
 826                 break;
 827         case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT:
 828                 if (likely(!rx_ctx->resync_nh_do_now))
 829                         return;
 830
 831                 /* head of next rec is already in, note that the sock_inq will
 832                  * include the currently parsed message when called from parser
 833                  */
 834                 sock_data = tcp_inq(sk);
 835                 if (sock_data > rcd_len) {
 836                         trace_tls_device_rx_resync_nh_delay(sk, sock_data,
 837                                                             rcd_len);
 838                         return;
 839                 }
 840
 841                 rx_ctx->resync_nh_do_now = 0;
 842                 seq += rcd_len;
 843                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 844                 break;
 845         case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC:
 846                 resync_req = atomic64_read(&rx_ctx->resync_async->req);
 847                 is_req_pending = resync_req;
 848                 if (likely(!is_req_pending))
 849                         return;
 850
 851                 if (!tls_device_rx_resync_async(rx_ctx->resync_async,
 852                                                 resync_req, &seq, &rcd_delta))
 853                         return;
 854                 tls_bigint_subtract(rcd_sn, rcd_delta);
 855                 break;
 856         }
 857
 858         tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn);
 859 }
 860
 861 static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx,
 862                                            struct tls_offload_context_rx *ctx,
 863                                            struct sock *sk, struct sk_buff *skb)
 864 {
 865         struct strp_msg *rxm;
 866
 867         /* device will request resyncs by itself based on stream scan */
 868         if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT)
 869                 return;
 870         /* already scheduled */
 871         if (ctx->resync_nh_do_now)
 872                 return;
 873         /* seen decrypted fragments since last fully-failed record */
 874         if (ctx->resync_nh_reset) {
 875                 ctx->resync_nh_reset = 0;
 876                 ctx->resync_nh.decrypted_failed = 1;
 877                 ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL;
 878                 return;
 879         }
 880
 881         if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt)
 882                 return;
 883
 884         /* doing resync, bump the next target in case it fails */
 885         if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL)
 886                 ctx->resync_nh.decrypted_tgt *= 2;
 887         else
 888                 ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL;
 889
 890         rxm = strp_msg(skb);
 891
 892         /* head of next rec is already in, parser will sync for us */
 893         if (tcp_inq(sk) > rxm->full_len) {
 894                 trace_tls_device_rx_resync_nh_schedule(sk);
 895                 ctx->resync_nh_do_now = 1;
 896         } else {
 897                 struct tls_prot_info *prot = &tls_ctx->prot_info;
 898                 u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE];
 899
 900                 memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size);
 901                 tls_bigint_increment(rcd_sn, prot->rec_seq_size);
 902
 903                 tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq,
 904                                      rcd_sn);
 905         }
 906 }
 907
 908 static int
 909 tls_device_reencrypt(struct sock *sk, struct tls_context *tls_ctx)
 910 {
 911         struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
 912         const struct tls_cipher_size_desc *cipher_sz;
 913         int err, offset, copy, data_len, pos;
 914         struct sk_buff *skb, *skb_iter;
 915         struct scatterlist sg[1];
 916         struct strp_msg *rxm;
 917         char *orig_buf, *buf;
 918
 919         switch (tls_ctx->crypto_recv.info.cipher_type) {
 920         case TLS_CIPHER_AES_GCM_128:
 921         case TLS_CIPHER_AES_GCM_256:
 922                 break;
 923         default:
 924                 return -EINVAL;
 925         }
 926         cipher_sz = &tls_cipher_size_desc[tls_ctx->crypto_recv.info.cipher_type];
 927
 928         rxm = strp_msg(tls_strp_msg(sw_ctx));
 929         orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv,
 930                            sk->sk_allocation);
 931         if (!orig_buf)
 932                 return -ENOMEM;
 933         buf = orig_buf;
 934
 935         err = tls_strp_msg_cow(sw_ctx);
 936         if (unlikely(err))
 937                 goto free_buf;
 938
 939         skb = tls_strp_msg(sw_ctx);
 940         rxm = strp_msg(skb);
 941         offset = rxm->offset;
 942
 943         sg_init_table(sg, 1);
 944         sg_set_buf(&sg[0], buf,
 945                    rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv);
 946         err = skb_copy_bits(skb, offset, buf, TLS_HEADER_SIZE + cipher_sz->iv);
 947         if (err)
 948                 goto free_buf;
 949
 950         /* We are interested only in the decrypted data not the auth */
 951         err = decrypt_skb(sk, sg);
 952         if (err != -EBADMSG)
 953                 goto free_buf;
 954         else
 955                 err = 0;
 956
 957         data_len = rxm->full_len - cipher_sz->tag;
 958
 959         if (skb_pagelen(skb) > offset) {
 960                 copy = min_t(int, skb_pagelen(skb) - offset, data_len);
 961
 962                 if (skb->decrypted) {
 963                         err = skb_store_bits(skb, offset, buf, copy);
 964                         if (err)
 965                                 goto free_buf;
 966                 }
 967
 968                 offset += copy;
 969                 buf += copy;
 970         }
 971
 972         pos = skb_pagelen(skb);
 973         skb_walk_frags(skb, skb_iter) {
 974                 int frag_pos;
 975
 976                 /* Practically all frags must belong to msg if reencrypt
 977                  * is needed with current strparser and coalescing logic,
 978                  * but strparser may "get optimized", so let's be safe.
 979                  */
 980                 if (pos + skb_iter->len <= offset)
 981                         goto done_with_frag;
 982                 if (pos >= data_len + rxm->offset)
 983                         break;
 984
 985                 frag_pos = offset - pos;
 986                 copy = min_t(int, skb_iter->len - frag_pos,
 987                              data_len + rxm->offset - offset);
 988
 989                 if (skb_iter->decrypted) {
 990                         err = skb_store_bits(skb_iter, frag_pos, buf, copy);
 991                         if (err)
 992                                 goto free_buf;
 993                 }
 994
 995                 offset += copy;
 996                 buf += copy;
 997 done_with_frag:
 998                 pos += skb_iter->len;
 999         }
1000
1001 free_buf:
1002         kfree(orig_buf);
1003         return err;
1004 }
1005
1006 int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx)
1007 {
1008         struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx);
1009         struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx);
1010         struct sk_buff *skb = tls_strp_msg(sw_ctx);
1011         struct strp_msg *rxm = strp_msg(skb);
1012         int is_decrypted, is_encrypted;
1013
1014         if (!tls_strp_msg_mixed_decrypted(sw_ctx)) {
1015                 is_decrypted = skb->decrypted;
1016                 is_encrypted = !is_decrypted;
1017         } else {
1018                 is_decrypted = 0;
1019                 is_encrypted = 0;
1020         }
1021
1022         trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len,
1023                                    tls_ctx->rx.rec_seq, rxm->full_len,
1024                                    is_encrypted, is_decrypted);
1025
1026         if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) {
1027                 if (likely(is_encrypted || is_decrypted))
1028                         return is_decrypted;
1029
1030                 /* After tls_device_down disables the offload, the next SKB will
1031                  * likely have initial fragments decrypted, and final ones not
1032                  * decrypted. We need to reencrypt that single SKB.
1033                  */
1034                 return tls_device_reencrypt(sk, tls_ctx);
1035         }
1036
1037         /* Return immediately if the record is either entirely plaintext or
1038          * entirely ciphertext. Otherwise handle reencrypt partially decrypted
1039          * record.
1040          */
1041         if (is_decrypted) {
1042                 ctx->resync_nh_reset = 1;
1043                 return is_decrypted;
1044         }
1045         if (is_encrypted) {
1046                 tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb);
1047                 return 0;
1048         }
1049
1050         ctx->resync_nh_reset = 1;
1051         return tls_device_reencrypt(sk, tls_ctx);
1052 }
1053
1054 static void tls_device_attach(struct tls_context *ctx, struct sock *sk,
1055                               struct net_device *netdev)
1056 {
1057         if (sk->sk_destruct != tls_device_sk_destruct) {
1058                 refcount_set(&ctx->refcount, 1);
1059                 dev_hold(netdev);
1060                 RCU_INIT_POINTER(ctx->netdev, netdev);
1061                 spin_lock_irq(&tls_device_lock);
1062                 list_add_tail(&ctx->list, &tls_device_list);
1063                 spin_unlock_irq(&tls_device_lock);
1064
1065                 ctx->sk_destruct = sk->sk_destruct;
1066                 smp_store_release(&sk->sk_destruct, tls_device_sk_destruct);
1067         }
1068 }
1069
1070 int tls_set_device_offload(struct sock *sk, struct tls_context *ctx)
1071 {
1072         struct tls_context *tls_ctx = tls_get_ctx(sk);
1073         struct tls_prot_info *prot = &tls_ctx->prot_info;
1074         const struct tls_cipher_size_desc *cipher_sz;
1075         struct tls_record_info *start_marker_record;
1076         struct tls_offload_context_tx *offload_ctx;
1077         struct tls_crypto_info *crypto_info;
1078         struct net_device *netdev;
1079         char *iv, *rec_seq;
1080         struct sk_buff *skb;
1081         __be64 rcd_sn;
1082         int rc;
1083
1084         if (!ctx)
1085                 return -EINVAL;
1086
1087         if (ctx->priv_ctx_tx)
1088                 return -EEXIST;
1089
1090         netdev = get_netdev_for_sock(sk);
1091         if (!netdev) {
1092                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1093                 return -EINVAL;
1094         }
1095
1096         if (!(netdev->features & NETIF_F_HW_TLS_TX)) {
1097                 rc = -EOPNOTSUPP;
1098                 goto release_netdev;
1099         }
1100
1101         crypto_info = &ctx->crypto_send.info;
1102         if (crypto_info->version != TLS_1_2_VERSION) {
1103                 rc = -EOPNOTSUPP;
1104                 goto release_netdev;
1105         }
1106
1107         switch (crypto_info->cipher_type) {
1108         case TLS_CIPHER_AES_GCM_128:
1109                 iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv;
1110                 rec_seq =
1111                  ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq;
1112                 break;
1113         case TLS_CIPHER_AES_GCM_256:
1114                 iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv;
1115                 rec_seq =
1116                  ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq;
1117                 break;
1118         default:
1119                 rc = -EINVAL;
1120                 goto release_netdev;
1121         }
1122         cipher_sz = &tls_cipher_size_desc[crypto_info->cipher_type];
1123
1124         /* Sanity-check the rec_seq_size for stack allocations */
1125         if (cipher_sz->rec_seq > TLS_MAX_REC_SEQ_SIZE) {
1126                 rc = -EINVAL;
1127                 goto release_netdev;
1128         }
1129
1130         prot->version = crypto_info->version;
1131         prot->cipher_type = crypto_info->cipher_type;
1132         prot->prepend_size = TLS_HEADER_SIZE + cipher_sz->iv;
1133         prot->tag_size = cipher_sz->tag;
1134         prot->overhead_size = prot->prepend_size + prot->tag_size;
1135         prot->iv_size = cipher_sz->iv;
1136         prot->salt_size = cipher_sz->salt;
1137         ctx->tx.iv = kmalloc(cipher_sz->iv + cipher_sz->salt, GFP_KERNEL);
1138         if (!ctx->tx.iv) {
1139                 rc = -ENOMEM;
1140                 goto release_netdev;
1141         }
1142
1143         memcpy(ctx->tx.iv + cipher_sz->salt, iv, cipher_sz->iv);
1144
1145         prot->rec_seq_size = cipher_sz->rec_seq;
1146         ctx->tx.rec_seq = kmemdup(rec_seq, cipher_sz->rec_seq, GFP_KERNEL);
1147         if (!ctx->tx.rec_seq) {
1148                 rc = -ENOMEM;
1149                 goto free_iv;
1150         }
1151
1152         start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL);
1153         if (!start_marker_record) {
1154                 rc = -ENOMEM;
1155                 goto free_rec_seq;
1156         }
1157
1158         offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL);
1159         if (!offload_ctx) {
1160                 rc = -ENOMEM;
1161                 goto free_marker_record;
1162         }
1163
1164         rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info);
1165         if (rc)
1166                 goto free_offload_ctx;
1167
1168         /* start at rec_seq - 1 to account for the start marker record */
1169         memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn));
1170         offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1;
1171
1172         start_marker_record->end_seq = tcp_sk(sk)->write_seq;
1173         start_marker_record->len = 0;
1174         start_marker_record->num_frags = 0;
1175
1176         INIT_WORK(&offload_ctx->destruct_work, tls_device_tx_del_task);
1177         offload_ctx->ctx = ctx;
1178
1179         INIT_LIST_HEAD(&offload_ctx->records_list);
1180         list_add_tail(&start_marker_record->list, &offload_ctx->records_list);
1181         spin_lock_init(&offload_ctx->lock);
1182         sg_init_table(offload_ctx->sg_tx_data,
1183                       ARRAY_SIZE(offload_ctx->sg_tx_data));
1184
1185         clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked);
1186         ctx->push_pending_record = tls_device_push_pending_record;
1187
1188         /* TLS offload is greatly simplified if we don't send
1189          * SKBs where only part of the payload needs to be encrypted.
1190          * So mark the last skb in the write queue as end of record.
1191          */
1192         skb = tcp_write_queue_tail(sk);
1193         if (skb)
1194                 TCP_SKB_CB(skb)->eor = 1;
1195
1196         /* Avoid offloading if the device is down
1197          * We don't want to offload new flows after
1198          * the NETDEV_DOWN event
1199          *
1200          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1201          * handler thus protecting from the device going down before
1202          * ctx was added to tls_device_list.
1203          */
1204         down_read(&device_offload_lock);
1205         if (!(netdev->flags & IFF_UP)) {
1206                 rc = -EINVAL;
1207                 goto release_lock;
1208         }
1209
1210         ctx->priv_ctx_tx = offload_ctx;
1211         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX,
1212                                              &ctx->crypto_send.info,
1213                                              tcp_sk(sk)->write_seq);
1214         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX,
1215                                      tcp_sk(sk)->write_seq, rec_seq, rc);
1216         if (rc)
1217                 goto release_lock;
1218
1219         tls_device_attach(ctx, sk, netdev);
1220         up_read(&device_offload_lock);
1221
1222         /* following this assignment tls_is_skb_tx_device_offloaded
1223          * will return true and the context might be accessed
1224          * by the netdev's xmit function.
1225          */
1226         smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb);
1227         dev_put(netdev);
1228
1229         return 0;
1230
1231 release_lock:
1232         up_read(&device_offload_lock);
1233         clean_acked_data_disable(inet_csk(sk));
1234         crypto_free_aead(offload_ctx->aead_send);
1235 free_offload_ctx:
1236         kfree(offload_ctx);
1237         ctx->priv_ctx_tx = NULL;
1238 free_marker_record:
1239         kfree(start_marker_record);
1240 free_rec_seq:
1241         kfree(ctx->tx.rec_seq);
1242 free_iv:
1243         kfree(ctx->tx.iv);
1244 release_netdev:
1245         dev_put(netdev);
1246         return rc;
1247 }
1248
1249 int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx)
1250 {
1251         struct tls12_crypto_info_aes_gcm_128 *info;
1252         struct tls_offload_context_rx *context;
1253         struct net_device *netdev;
1254         int rc = 0;
1255
1256         if (ctx->crypto_recv.info.version != TLS_1_2_VERSION)
1257                 return -EOPNOTSUPP;
1258
1259         netdev = get_netdev_for_sock(sk);
1260         if (!netdev) {
1261                 pr_err_ratelimited("%s: netdev not found\n", __func__);
1262                 return -EINVAL;
1263         }
1264
1265         if (!(netdev->features & NETIF_F_HW_TLS_RX)) {
1266                 rc = -EOPNOTSUPP;
1267                 goto release_netdev;
1268         }
1269
1270         /* Avoid offloading if the device is down
1271          * We don't want to offload new flows after
1272          * the NETDEV_DOWN event
1273          *
1274          * device_offload_lock is taken in tls_devices's NETDEV_DOWN
1275          * handler thus protecting from the device going down before
1276          * ctx was added to tls_device_list.
1277          */
1278         down_read(&device_offload_lock);
1279         if (!(netdev->flags & IFF_UP)) {
1280                 rc = -EINVAL;
1281                 goto release_lock;
1282         }
1283
1284         context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL);
1285         if (!context) {
1286                 rc = -ENOMEM;
1287                 goto release_lock;
1288         }
1289         context->resync_nh_reset = 1;
1290
1291         ctx->priv_ctx_rx = context;
1292         rc = tls_set_sw_offload(sk, ctx, 0);
1293         if (rc)
1294                 goto release_ctx;
1295
1296         rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX,
1297                                              &ctx->crypto_recv.info,
1298                                              tcp_sk(sk)->copied_seq);
1299         info = (void *)&ctx->crypto_recv.info;
1300         trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX,
1301                                      tcp_sk(sk)->copied_seq, info->rec_seq, rc);
1302         if (rc)
1303                 goto free_sw_resources;
1304
1305         tls_device_attach(ctx, sk, netdev);
1306         up_read(&device_offload_lock);
1307
1308         dev_put(netdev);
1309
1310         return 0;
1311
1312 free_sw_resources:
1313         up_read(&device_offload_lock);
1314         tls_sw_free_resources_rx(sk);
1315         down_read(&device_offload_lock);
1316 release_ctx:
1317         ctx->priv_ctx_rx = NULL;
1318 release_lock:
1319         up_read(&device_offload_lock);
1320 release_netdev:
1321         dev_put(netdev);
1322         return rc;
1323 }
1324
1325 void tls_device_offload_cleanup_rx(struct sock *sk)
1326 {
1327         struct tls_context *tls_ctx = tls_get_ctx(sk);
1328         struct net_device *netdev;
1329
1330         down_read(&device_offload_lock);
1331         netdev = rcu_dereference_protected(tls_ctx->netdev,
1332                                            lockdep_is_held(&device_offload_lock));
1333         if (!netdev)
1334                 goto out;
1335
1336         netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx,
1337                                         TLS_OFFLOAD_CTX_DIR_RX);
1338
1339         if (tls_ctx->tx_conf != TLS_HW) {
1340                 dev_put(netdev);
1341                 rcu_assign_pointer(tls_ctx->netdev, NULL);
1342         } else {
1343                 set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
1344         }
1345 out:
1346         up_read(&device_offload_lock);
1347         tls_sw_release_resources_rx(sk);
1348 }
1349
1350 static int tls_device_down(struct net_device *netdev)
1351 {
1352         struct tls_context *ctx, *tmp;
1353         unsigned long flags;
1354         LIST_HEAD(list);
1355
1356         /* Request a write lock to block new offload attempts */
1357         down_write(&device_offload_lock);
1358
1359         spin_lock_irqsave(&tls_device_lock, flags);
1360         list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) {
1361                 struct net_device *ctx_netdev =
1362                         rcu_dereference_protected(ctx->netdev,
1363                                                   lockdep_is_held(&device_offload_lock));
1364
1365                 if (ctx_netdev != netdev ||
1366                     !refcount_inc_not_zero(&ctx->refcount))
1367                         continue;
1368
1369                 list_move(&ctx->list, &list);
1370         }
1371         spin_unlock_irqrestore(&tls_device_lock, flags);
1372
1373         list_for_each_entry_safe(ctx, tmp, &list, list) {
1374                 /* Stop offloaded TX and switch to the fallback.
1375                  * tls_is_skb_tx_device_offloaded will return false.
1376                  */
1377                 WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw);
1378
1379                 /* Stop the RX and TX resync.
1380                  * tls_dev_resync must not be called after tls_dev_del.
1381                  */
1382                 rcu_assign_pointer(ctx->netdev, NULL);
1383
1384                 /* Start skipping the RX resync logic completely. */
1385                 set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags);
1386
1387                 /* Sync with inflight packets. After this point:
1388                  * TX: no non-encrypted packets will be passed to the driver.
1389                  * RX: resync requests from the driver will be ignored.
1390                  */
1391                 synchronize_net();
1392
1393                 /* Release the offload context on the driver side. */
1394                 if (ctx->tx_conf == TLS_HW)
1395                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1396                                                         TLS_OFFLOAD_CTX_DIR_TX);
1397                 if (ctx->rx_conf == TLS_HW &&
1398                     !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags))
1399                         netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
1400                                                         TLS_OFFLOAD_CTX_DIR_RX);
1401
1402                 dev_put(netdev);
1403
1404                 /* Move the context to a separate list for two reasons:
1405                  * 1. When the context is deallocated, list_del is called.
1406                  * 2. It's no longer an offloaded context, so we don't want to
1407                  *    run offload-specific code on this context.
1408                  */
1409                 spin_lock_irqsave(&tls_device_lock, flags);
1410                 list_move_tail(&ctx->list, &tls_device_down_list);
1411                 spin_unlock_irqrestore(&tls_device_lock, flags);
1412
1413                 /* Device contexts for RX and TX will be freed in on sk_destruct
1414                  * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW.
1415                  * Now release the ref taken above.
1416                  */
1417                 if (refcount_dec_and_test(&ctx->refcount)) {
1418                         /* sk_destruct ran after tls_device_down took a ref, and
1419                          * it returned early. Complete the destruction here.
1420                          */
1421                         list_del(&ctx->list);
1422                         tls_device_free_ctx(ctx);
1423                 }
1424         }
1425
1426         up_write(&device_offload_lock);
1427
1428         flush_workqueue(destruct_wq);
1429
1430         return NOTIFY_DONE;
1431 }
1432
1433 static int tls_dev_event(struct notifier_block *this, unsigned long event,
1434                          void *ptr)
1435 {
1436         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1437
1438         if (!dev->tlsdev_ops &&
1439             !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX)))
1440                 return NOTIFY_DONE;
1441
1442         switch (event) {
1443         case NETDEV_REGISTER:
1444         case NETDEV_FEAT_CHANGE:
1445                 if (netif_is_bond_master(dev))
1446                         return NOTIFY_DONE;
1447                 if ((dev->features & NETIF_F_HW_TLS_RX) &&
1448                     !dev->tlsdev_ops->tls_dev_resync)
1449                         return NOTIFY_BAD;
1450
1451                 if  (dev->tlsdev_ops &&
1452                      dev->tlsdev_ops->tls_dev_add &&
1453                      dev->tlsdev_ops->tls_dev_del)
1454                         return NOTIFY_DONE;
1455                 else
1456                         return NOTIFY_BAD;
1457         case NETDEV_DOWN:
1458                 return tls_device_down(dev);
1459         }
1460         return NOTIFY_DONE;
1461 }
1462
1463 static struct notifier_block tls_dev_notifier = {
1464         .notifier_call  = tls_dev_event,
1465 };
1466
1467 int __init tls_device_init(void)
1468 {
1469         int err;
1470
1471         destruct_wq = alloc_workqueue("ktls_device_destruct", 0, 0);
1472         if (!destruct_wq)
1473                 return -ENOMEM;
1474
1475         err = register_netdevice_notifier(&tls_dev_notifier);
1476         if (err)
1477                 destroy_workqueue(destruct_wq);
1478
1479         return err;
1480 }
1481
1482 void __exit tls_device_cleanup(void)
1483 {
1484         unregister_netdevice_notifier(&tls_dev_notifier);
1485         destroy_workqueue(destruct_wq);
1486         clean_acked_data_flush();
1487 }