net/tls/tls_main.c

   1 /*
   2  * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
   3  * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #include <linux/module.h>
  35
  36 #include <net/tcp.h>
  37 #include <net/inet_common.h>
  38 #include <linux/highmem.h>
  39 #include <linux/netdevice.h>
  40 #include <linux/sched/signal.h>
  41 #include <linux/inetdevice.h>
  42
  43 #include <net/tls.h>
  44
  45 MODULE_AUTHOR("Mellanox Technologies");
  46 MODULE_DESCRIPTION("Transport Layer Security Support");
  47 MODULE_LICENSE("Dual BSD/GPL");
  48 MODULE_ALIAS_TCP_ULP("tls");
  49
  50 enum {
  51         TLSV4,
  52         TLSV6,
  53         TLS_NUM_PROTS,
  54 };
  55
  56 static struct proto *saved_tcpv6_prot;
  57 static DEFINE_MUTEX(tcpv6_prot_mutex);
  58 static LIST_HEAD(device_list);
  59 static DEFINE_MUTEX(device_mutex);
  60 static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
  61 static struct proto_ops tls_sw_proto_ops;
  62
  63 static void update_sk_prot(struct sock *sk, struct tls_context *ctx)
  64 {
  65         int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
  66
  67         sk->sk_prot = &tls_prots[ip_ver][ctx->tx_conf][ctx->rx_conf];
  68 }
  69
  70 int wait_on_pending_writer(struct sock *sk, long *timeo)
  71 {
  72         int rc = 0;
  73         DEFINE_WAIT_FUNC(wait, woken_wake_function);
  74
  75         add_wait_queue(sk_sleep(sk), &wait);
  76         while (1) {
  77                 if (!*timeo) {
  78                         rc = -EAGAIN;
  79                         break;
  80                 }
  81
  82                 if (signal_pending(current)) {
  83                         rc = sock_intr_errno(*timeo);
  84                         break;
  85                 }
  86
  87                 if (sk_wait_event(sk, timeo, !sk->sk_write_pending, &wait))
  88                         break;
  89         }
  90         remove_wait_queue(sk_sleep(sk), &wait);
  91         return rc;
  92 }
  93
  94 int tls_push_sg(struct sock *sk,
  95                 struct tls_context *ctx,
  96                 struct scatterlist *sg,
  97                 u16 first_offset,
  98                 int flags)
  99 {
 100         int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
 101         int ret = 0;
 102         struct page *p;
 103         size_t size;
 104         int offset = first_offset;
 105
 106         size = sg->length - offset;
 107         offset += sg->offset;
 108
 109         ctx->in_tcp_sendpages = true;
 110         while (1) {
 111                 if (sg_is_last(sg))
 112                         sendpage_flags = flags;
 113
 114                 /* is sending application-limited? */
 115                 tcp_rate_check_app_limited(sk);
 116                 p = sg_page(sg);
 117 retry:
 118                 ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
 119
 120                 if (ret != size) {
 121                         if (ret > 0) {
 122                                 offset += ret;
 123                                 size -= ret;
 124                                 goto retry;
 125                         }
 126
 127                         offset -= sg->offset;
 128                         ctx->partially_sent_offset = offset;
 129                         ctx->partially_sent_record = (void *)sg;
 130                         ctx->in_tcp_sendpages = false;
 131                         return ret;
 132                 }
 133
 134                 put_page(p);
 135                 sk_mem_uncharge(sk, sg->length);
 136                 sg = sg_next(sg);
 137                 if (!sg)
 138                         break;
 139
 140                 offset = sg->offset;
 141                 size = sg->length;
 142         }
 143
 144         clear_bit(TLS_PENDING_CLOSED_RECORD, &ctx->flags);
 145         ctx->in_tcp_sendpages = false;
 146         ctx->sk_write_space(sk);
 147
 148         return 0;
 149 }
 150
 151 static int tls_handle_open_record(struct sock *sk, int flags)
 152 {
 153         struct tls_context *ctx = tls_get_ctx(sk);
 154
 155         if (tls_is_pending_open_record(ctx))
 156                 return ctx->push_pending_record(sk, flags);
 157
 158         return 0;
 159 }
 160
 161 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
 162                       unsigned char *record_type)
 163 {
 164         struct cmsghdr *cmsg;
 165         int rc = -EINVAL;
 166
 167         for_each_cmsghdr(cmsg, msg) {
 168                 if (!CMSG_OK(msg, cmsg))
 169                         return -EINVAL;
 170                 if (cmsg->cmsg_level != SOL_TLS)
 171                         continue;
 172
 173                 switch (cmsg->cmsg_type) {
 174                 case TLS_SET_RECORD_TYPE:
 175                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
 176                                 return -EINVAL;
 177
 178                         if (msg->msg_flags & MSG_MORE)
 179                                 return -EINVAL;
 180
 181                         rc = tls_handle_open_record(sk, msg->msg_flags);
 182                         if (rc)
 183                                 return rc;
 184
 185                         *record_type = *(unsigned char *)CMSG_DATA(cmsg);
 186                         rc = 0;
 187                         break;
 188                 default:
 189                         return -EINVAL;
 190                 }
 191         }
 192
 193         return rc;
 194 }
 195
 196 int tls_push_pending_closed_record(struct sock *sk, struct tls_context *ctx,
 197                                    int flags, long *timeo)
 198 {
 199         struct scatterlist *sg;
 200         u16 offset;
 201
 202         if (!tls_is_partially_sent_record(ctx))
 203                 return ctx->push_pending_record(sk, flags);
 204
 205         sg = ctx->partially_sent_record;
 206         offset = ctx->partially_sent_offset;
 207
 208         ctx->partially_sent_record = NULL;
 209         return tls_push_sg(sk, ctx, sg, offset, flags);
 210 }
 211
 212 static void tls_write_space(struct sock *sk)
 213 {
 214         struct tls_context *ctx = tls_get_ctx(sk);
 215
 216         /* We are already sending pages, ignore notification */
 217         if (ctx->in_tcp_sendpages)
 218                 return;
 219
 220         if (!sk->sk_write_pending && tls_is_pending_closed_record(ctx)) {
 221                 gfp_t sk_allocation = sk->sk_allocation;
 222                 int rc;
 223                 long timeo = 0;
 224
 225                 sk->sk_allocation = GFP_ATOMIC;
 226                 rc = tls_push_pending_closed_record(sk, ctx,
 227                                                     MSG_DONTWAIT |
 228                                                     MSG_NOSIGNAL,
 229                                                     &timeo);
 230                 sk->sk_allocation = sk_allocation;
 231
 232                 if (rc < 0)
 233                         return;
 234         }
 235
 236         ctx->sk_write_space(sk);
 237 }
 238
 239 static void tls_sk_proto_close(struct sock *sk, long timeout)
 240 {
 241         struct tls_context *ctx = tls_get_ctx(sk);
 242         long timeo = sock_sndtimeo(sk, 0);
 243         void (*sk_proto_close)(struct sock *sk, long timeout);
 244         bool free_ctx = false;
 245
 246         lock_sock(sk);
 247         sk_proto_close = ctx->sk_proto_close;
 248
 249         if ((ctx->tx_conf == TLS_HW_RECORD && ctx->rx_conf == TLS_HW_RECORD) ||
 250             (ctx->tx_conf == TLS_BASE && ctx->rx_conf == TLS_BASE)) {
 251                 free_ctx = true;
 252                 goto skip_tx_cleanup;
 253         }
 254
 255         if (!tls_complete_pending_work(sk, ctx, 0, &timeo))
 256                 tls_handle_open_record(sk, 0);
 257
 258         if (ctx->partially_sent_record) {
 259                 struct scatterlist *sg = ctx->partially_sent_record;
 260
 261                 while (1) {
 262                         put_page(sg_page(sg));
 263                         sk_mem_uncharge(sk, sg->length);
 264
 265                         if (sg_is_last(sg))
 266                                 break;
 267                         sg++;
 268                 }
 269         }
 270
 271         /* We need these for tls_sw_fallback handling of other packets */
 272         if (ctx->tx_conf == TLS_SW) {
 273                 kfree(ctx->tx.rec_seq);
 274                 kfree(ctx->tx.iv);
 275                 tls_sw_free_resources_tx(sk);
 276         }
 277
 278         if (ctx->rx_conf == TLS_SW) {
 279                 kfree(ctx->rx.rec_seq);
 280                 kfree(ctx->rx.iv);
 281                 tls_sw_free_resources_rx(sk);
 282         }
 283
 284 #ifdef CONFIG_TLS_DEVICE
 285         if (ctx->rx_conf == TLS_HW)
 286                 tls_device_offload_cleanup_rx(sk);
 287
 288         if (ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW) {
 289 #else
 290         {
 291 #endif
 292                 kfree(ctx);
 293                 ctx = NULL;
 294         }
 295
 296 skip_tx_cleanup:
 297         release_sock(sk);
 298         sk_proto_close(sk, timeout);
 299         /* free ctx for TLS_HW_RECORD, used by tcp_set_state
 300          * for sk->sk_prot->unhash [tls_hw_unhash]
 301          */
 302         if (free_ctx)
 303                 kfree(ctx);
 304 }
 305
 306 static int do_tls_getsockopt_tx(struct sock *sk, char __user *optval,
 307                                 int __user *optlen)
 308 {
 309         int rc = 0;
 310         struct tls_context *ctx = tls_get_ctx(sk);
 311         struct tls_crypto_info *crypto_info;
 312         int len;
 313
 314         if (get_user(len, optlen))
 315                 return -EFAULT;
 316
 317         if (!optval || (len < sizeof(*crypto_info))) {
 318                 rc = -EINVAL;
 319                 goto out;
 320         }
 321
 322         if (!ctx) {
 323                 rc = -EBUSY;
 324                 goto out;
 325         }
 326
 327         /* get user crypto info */
 328         crypto_info = &ctx->crypto_send;
 329
 330         if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
 331                 rc = -EBUSY;
 332                 goto out;
 333         }
 334
 335         if (len == sizeof(*crypto_info)) {
 336                 if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
 337                         rc = -EFAULT;
 338                 goto out;
 339         }
 340
 341         switch (crypto_info->cipher_type) {
 342         case TLS_CIPHER_AES_GCM_128: {
 343                 struct tls12_crypto_info_aes_gcm_128 *
 344                   crypto_info_aes_gcm_128 =
 345                   container_of(crypto_info,
 346                                struct tls12_crypto_info_aes_gcm_128,
 347                                info);
 348
 349                 if (len != sizeof(*crypto_info_aes_gcm_128)) {
 350                         rc = -EINVAL;
 351                         goto out;
 352                 }
 353                 lock_sock(sk);
 354                 memcpy(crypto_info_aes_gcm_128->iv,
 355                        ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
 356                        TLS_CIPHER_AES_GCM_128_IV_SIZE);
 357                 memcpy(crypto_info_aes_gcm_128->rec_seq, ctx->tx.rec_seq,
 358                        TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
 359                 release_sock(sk);
 360                 if (copy_to_user(optval,
 361                                  crypto_info_aes_gcm_128,
 362                                  sizeof(*crypto_info_aes_gcm_128)))
 363                         rc = -EFAULT;
 364                 break;
 365         }
 366         default:
 367                 rc = -EINVAL;
 368         }
 369
 370 out:
 371         return rc;
 372 }
 373
 374 static int do_tls_getsockopt(struct sock *sk, int optname,
 375                              char __user *optval, int __user *optlen)
 376 {
 377         int rc = 0;
 378
 379         switch (optname) {
 380         case TLS_TX:
 381                 rc = do_tls_getsockopt_tx(sk, optval, optlen);
 382                 break;
 383         default:
 384                 rc = -ENOPROTOOPT;
 385                 break;
 386         }
 387         return rc;
 388 }
 389
 390 static int tls_getsockopt(struct sock *sk, int level, int optname,
 391                           char __user *optval, int __user *optlen)
 392 {
 393         struct tls_context *ctx = tls_get_ctx(sk);
 394
 395         if (level != SOL_TLS)
 396                 return ctx->getsockopt(sk, level, optname, optval, optlen);
 397
 398         return do_tls_getsockopt(sk, optname, optval, optlen);
 399 }
 400
 401 static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
 402                                   unsigned int optlen, int tx)
 403 {
 404         struct tls_crypto_info *crypto_info;
 405         struct tls_context *ctx = tls_get_ctx(sk);
 406         int rc = 0;
 407         int conf;
 408
 409         if (!optval || (optlen < sizeof(*crypto_info))) {
 410                 rc = -EINVAL;
 411                 goto out;
 412         }
 413
 414         if (tx)
 415                 crypto_info = &ctx->crypto_send;
 416         else
 417                 crypto_info = &ctx->crypto_recv;
 418
 419         /* Currently we don't support set crypto info more than one time */
 420         if (TLS_CRYPTO_INFO_READY(crypto_info)) {
 421                 rc = -EBUSY;
 422                 goto out;
 423         }
 424
 425         rc = copy_from_user(crypto_info, optval, sizeof(*crypto_info));
 426         if (rc) {
 427                 rc = -EFAULT;
 428                 goto err_crypto_info;
 429         }
 430
 431         /* check version */
 432         if (crypto_info->version != TLS_1_2_VERSION) {
 433                 rc = -ENOTSUPP;
 434                 goto err_crypto_info;
 435         }
 436
 437         switch (crypto_info->cipher_type) {
 438         case TLS_CIPHER_AES_GCM_128: {
 439                 if (optlen != sizeof(struct tls12_crypto_info_aes_gcm_128)) {
 440                         rc = -EINVAL;
 441                         goto err_crypto_info;
 442                 }
 443                 rc = copy_from_user(crypto_info + 1, optval + sizeof(*crypto_info),
 444                                     optlen - sizeof(*crypto_info));
 445                 if (rc) {
 446                         rc = -EFAULT;
 447                         goto err_crypto_info;
 448                 }
 449                 break;
 450         }
 451         default:
 452                 rc = -EINVAL;
 453                 goto err_crypto_info;
 454         }
 455
 456         if (tx) {
 457 #ifdef CONFIG_TLS_DEVICE
 458                 rc = tls_set_device_offload(sk, ctx);
 459                 conf = TLS_HW;
 460                 if (rc) {
 461 #else
 462                 {
 463 #endif
 464                         rc = tls_set_sw_offload(sk, ctx, 1);
 465                         conf = TLS_SW;
 466                 }
 467         } else {
 468 #ifdef CONFIG_TLS_DEVICE
 469                 rc = tls_set_device_offload_rx(sk, ctx);
 470                 conf = TLS_HW;
 471                 if (rc) {
 472 #else
 473                 {
 474 #endif
 475                         rc = tls_set_sw_offload(sk, ctx, 0);
 476                         conf = TLS_SW;
 477                 }
 478         }
 479
 480         if (rc)
 481                 goto err_crypto_info;
 482
 483         if (tx)
 484                 ctx->tx_conf = conf;
 485         else
 486                 ctx->rx_conf = conf;
 487         update_sk_prot(sk, ctx);
 488         if (tx) {
 489                 ctx->sk_write_space = sk->sk_write_space;
 490                 sk->sk_write_space = tls_write_space;
 491         } else {
 492                 sk->sk_socket->ops = &tls_sw_proto_ops;
 493         }
 494         goto out;
 495
 496 err_crypto_info:
 497         memset(crypto_info, 0, sizeof(*crypto_info));
 498 out:
 499         return rc;
 500 }
 501
 502 static int do_tls_setsockopt(struct sock *sk, int optname,
 503                              char __user *optval, unsigned int optlen)
 504 {
 505         int rc = 0;
 506
 507         switch (optname) {
 508         case TLS_TX:
 509         case TLS_RX:
 510                 lock_sock(sk);
 511                 rc = do_tls_setsockopt_conf(sk, optval, optlen,
 512                                             optname == TLS_TX);
 513                 release_sock(sk);
 514                 break;
 515         default:
 516                 rc = -ENOPROTOOPT;
 517                 break;
 518         }
 519         return rc;
 520 }
 521
 522 static int tls_setsockopt(struct sock *sk, int level, int optname,
 523                           char __user *optval, unsigned int optlen)
 524 {
 525         struct tls_context *ctx = tls_get_ctx(sk);
 526
 527         if (level != SOL_TLS)
 528                 return ctx->setsockopt(sk, level, optname, optval, optlen);
 529
 530         return do_tls_setsockopt(sk, optname, optval, optlen);
 531 }
 532
 533 static struct tls_context *create_ctx(struct sock *sk)
 534 {
 535         struct inet_connection_sock *icsk = inet_csk(sk);
 536         struct tls_context *ctx;
 537
 538         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
 539         if (!ctx)
 540                 return NULL;
 541
 542         icsk->icsk_ulp_data = ctx;
 543         return ctx;
 544 }
 545
 546 static int tls_hw_prot(struct sock *sk)
 547 {
 548         struct tls_context *ctx;
 549         struct tls_device *dev;
 550         int rc = 0;
 551
 552         mutex_lock(&device_mutex);
 553         list_for_each_entry(dev, &device_list, dev_list) {
 554                 if (dev->feature && dev->feature(dev)) {
 555                         ctx = create_ctx(sk);
 556                         if (!ctx)
 557                                 goto out;
 558
 559                         ctx->hash = sk->sk_prot->hash;
 560                         ctx->unhash = sk->sk_prot->unhash;
 561                         ctx->sk_proto_close = sk->sk_prot->close;
 562                         ctx->rx_conf = TLS_HW_RECORD;
 563                         ctx->tx_conf = TLS_HW_RECORD;
 564                         update_sk_prot(sk, ctx);
 565                         rc = 1;
 566                         break;
 567                 }
 568         }
 569 out:
 570         mutex_unlock(&device_mutex);
 571         return rc;
 572 }
 573
 574 static void tls_hw_unhash(struct sock *sk)
 575 {
 576         struct tls_context *ctx = tls_get_ctx(sk);
 577         struct tls_device *dev;
 578
 579         mutex_lock(&device_mutex);
 580         list_for_each_entry(dev, &device_list, dev_list) {
 581                 if (dev->unhash)
 582                         dev->unhash(dev, sk);
 583         }
 584         mutex_unlock(&device_mutex);
 585         ctx->unhash(sk);
 586 }
 587
 588 static int tls_hw_hash(struct sock *sk)
 589 {
 590         struct tls_context *ctx = tls_get_ctx(sk);
 591         struct tls_device *dev;
 592         int err;
 593
 594         err = ctx->hash(sk);
 595         mutex_lock(&device_mutex);
 596         list_for_each_entry(dev, &device_list, dev_list) {
 597                 if (dev->hash)
 598                         err |= dev->hash(dev, sk);
 599         }
 600         mutex_unlock(&device_mutex);
 601
 602         if (err)
 603                 tls_hw_unhash(sk);
 604         return err;
 605 }
 606
 607 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
 608                          struct proto *base)
 609 {
 610         prot[TLS_BASE][TLS_BASE] = *base;
 611         prot[TLS_BASE][TLS_BASE].setsockopt     = tls_setsockopt;
 612         prot[TLS_BASE][TLS_BASE].getsockopt     = tls_getsockopt;
 613         prot[TLS_BASE][TLS_BASE].close          = tls_sk_proto_close;
 614
 615         prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 616         prot[TLS_SW][TLS_BASE].sendmsg          = tls_sw_sendmsg;
 617         prot[TLS_SW][TLS_BASE].sendpage         = tls_sw_sendpage;
 618
 619         prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
 620         prot[TLS_BASE][TLS_SW].recvmsg          = tls_sw_recvmsg;
 621         prot[TLS_BASE][TLS_SW].close            = tls_sk_proto_close;
 622
 623         prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
 624         prot[TLS_SW][TLS_SW].recvmsg    = tls_sw_recvmsg;
 625         prot[TLS_SW][TLS_SW].close      = tls_sk_proto_close;
 626
 627 #ifdef CONFIG_TLS_DEVICE
 628         prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 629         prot[TLS_HW][TLS_BASE].sendmsg          = tls_device_sendmsg;
 630         prot[TLS_HW][TLS_BASE].sendpage         = tls_device_sendpage;
 631
 632         prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
 633         prot[TLS_HW][TLS_SW].sendmsg            = tls_device_sendmsg;
 634         prot[TLS_HW][TLS_SW].sendpage           = tls_device_sendpage;
 635
 636         prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
 637
 638         prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
 639
 640         prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
 641 #endif
 642
 643         prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
 644         prot[TLS_HW_RECORD][TLS_HW_RECORD].hash         = tls_hw_hash;
 645         prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash       = tls_hw_unhash;
 646         prot[TLS_HW_RECORD][TLS_HW_RECORD].close        = tls_sk_proto_close;
 647 }
 648
 649 static int tls_init(struct sock *sk)
 650 {
 651         int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
 652         struct tls_context *ctx;
 653         int rc = 0;
 654
 655         if (tls_hw_prot(sk))
 656                 goto out;
 657
 658         /* The TLS ulp is currently supported only for TCP sockets
 659          * in ESTABLISHED state.
 660          * Supporting sockets in LISTEN state will require us
 661          * to modify the accept implementation to clone rather then
 662          * share the ulp context.
 663          */
 664         if (sk->sk_state != TCP_ESTABLISHED)
 665                 return -ENOTSUPP;
 666
 667         /* allocate tls context */
 668         ctx = create_ctx(sk);
 669         if (!ctx) {
 670                 rc = -ENOMEM;
 671                 goto out;
 672         }
 673         ctx->setsockopt = sk->sk_prot->setsockopt;
 674         ctx->getsockopt = sk->sk_prot->getsockopt;
 675         ctx->sk_proto_close = sk->sk_prot->close;
 676
 677         /* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
 678         if (ip_ver == TLSV6 &&
 679             unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) {
 680                 mutex_lock(&tcpv6_prot_mutex);
 681                 if (likely(sk->sk_prot != saved_tcpv6_prot)) {
 682                         build_protos(tls_prots[TLSV6], sk->sk_prot);
 683                         smp_store_release(&saved_tcpv6_prot, sk->sk_prot);
 684                 }
 685                 mutex_unlock(&tcpv6_prot_mutex);
 686         }
 687
 688         ctx->tx_conf = TLS_BASE;
 689         ctx->rx_conf = TLS_BASE;
 690         update_sk_prot(sk, ctx);
 691 out:
 692         return rc;
 693 }
 694
 695 void tls_register_device(struct tls_device *device)
 696 {
 697         mutex_lock(&device_mutex);
 698         list_add_tail(&device->dev_list, &device_list);
 699         mutex_unlock(&device_mutex);
 700 }
 701 EXPORT_SYMBOL(tls_register_device);
 702
 703 void tls_unregister_device(struct tls_device *device)
 704 {
 705         mutex_lock(&device_mutex);
 706         list_del(&device->dev_list);
 707         mutex_unlock(&device_mutex);
 708 }
 709 EXPORT_SYMBOL(tls_unregister_device);
 710
 711 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
 712         .name                   = "tls",
 713         .uid                    = TCP_ULP_TLS,
 714         .user_visible           = true,
 715         .owner                  = THIS_MODULE,
 716         .init                   = tls_init,
 717 };
 718
 719 static int __init tls_register(void)
 720 {
 721         build_protos(tls_prots[TLSV4], &tcp_prot);
 722
 723         tls_sw_proto_ops = inet_stream_ops;
 724         tls_sw_proto_ops.poll = tls_sw_poll;
 725         tls_sw_proto_ops.splice_read = tls_sw_splice_read;
 726
 727 #ifdef CONFIG_TLS_DEVICE
 728         tls_device_init();
 729 #endif
 730         tcp_register_ulp(&tcp_tls_ulp_ops);
 731
 732         return 0;
 733 }
 734
 735 static void __exit tls_unregister(void)
 736 {
 737         tcp_unregister_ulp(&tcp_tls_ulp_ops);
 738 #ifdef CONFIG_TLS_DEVICE
 739         tls_device_cleanup();
 740 #endif
 741 }
 742
 743 module_init(tls_register);
 744 module_exit(tls_unregister);