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 #include <linux/inet_diag.h>
  43
  44 #include <net/snmp.h>
  45 #include <net/tls.h>
  46 #include <net/tls_toe.h>
  47
  48 MODULE_AUTHOR("Mellanox Technologies");
  49 MODULE_DESCRIPTION("Transport Layer Security Support");
  50 MODULE_LICENSE("Dual BSD/GPL");
  51 MODULE_ALIAS_TCP_ULP("tls");
  52
  53 enum {
  54         TLSV4,
  55         TLSV6,
  56         TLS_NUM_PROTS,
  57 };
  58
  59 static const struct proto *saved_tcpv6_prot;
  60 static DEFINE_MUTEX(tcpv6_prot_mutex);
  61 static const struct proto *saved_tcpv4_prot;
  62 static DEFINE_MUTEX(tcpv4_prot_mutex);
  63 static struct proto tls_prots[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
  64 static struct proto_ops tls_sw_proto_ops;
  65 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
  66                          const struct proto *base);
  67
  68 void update_sk_prot(struct sock *sk, struct tls_context *ctx)
  69 {
  70         int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
  71
  72         WRITE_ONCE(sk->sk_prot,
  73                    &tls_prots[ip_ver][ctx->tx_conf][ctx->rx_conf]);
  74 }
  75
  76 int wait_on_pending_writer(struct sock *sk, long *timeo)
  77 {
  78         int rc = 0;
  79         DEFINE_WAIT_FUNC(wait, woken_wake_function);
  80
  81         add_wait_queue(sk_sleep(sk), &wait);
  82         while (1) {
  83                 if (!*timeo) {
  84                         rc = -EAGAIN;
  85                         break;
  86                 }
  87
  88                 if (signal_pending(current)) {
  89                         rc = sock_intr_errno(*timeo);
  90                         break;
  91                 }
  92
  93                 if (sk_wait_event(sk, timeo, !sk->sk_write_pending, &wait))
  94                         break;
  95         }
  96         remove_wait_queue(sk_sleep(sk), &wait);
  97         return rc;
  98 }
  99
 100 int tls_push_sg(struct sock *sk,
 101                 struct tls_context *ctx,
 102                 struct scatterlist *sg,
 103                 u16 first_offset,
 104                 int flags)
 105 {
 106         int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
 107         int ret = 0;
 108         struct page *p;
 109         size_t size;
 110         int offset = first_offset;
 111
 112         size = sg->length - offset;
 113         offset += sg->offset;
 114
 115         ctx->in_tcp_sendpages = true;
 116         while (1) {
 117                 if (sg_is_last(sg))
 118                         sendpage_flags = flags;
 119
 120                 /* is sending application-limited? */
 121                 tcp_rate_check_app_limited(sk);
 122                 p = sg_page(sg);
 123 retry:
 124                 ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
 125
 126                 if (ret != size) {
 127                         if (ret > 0) {
 128                                 offset += ret;
 129                                 size -= ret;
 130                                 goto retry;
 131                         }
 132
 133                         offset -= sg->offset;
 134                         ctx->partially_sent_offset = offset;
 135                         ctx->partially_sent_record = (void *)sg;
 136                         ctx->in_tcp_sendpages = false;
 137                         return ret;
 138                 }
 139
 140                 put_page(p);
 141                 sk_mem_uncharge(sk, sg->length);
 142                 sg = sg_next(sg);
 143                 if (!sg)
 144                         break;
 145
 146                 offset = sg->offset;
 147                 size = sg->length;
 148         }
 149
 150         ctx->in_tcp_sendpages = false;
 151
 152         return 0;
 153 }
 154
 155 static int tls_handle_open_record(struct sock *sk, int flags)
 156 {
 157         struct tls_context *ctx = tls_get_ctx(sk);
 158
 159         if (tls_is_pending_open_record(ctx))
 160                 return ctx->push_pending_record(sk, flags);
 161
 162         return 0;
 163 }
 164
 165 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
 166                       unsigned char *record_type)
 167 {
 168         struct cmsghdr *cmsg;
 169         int rc = -EINVAL;
 170
 171         for_each_cmsghdr(cmsg, msg) {
 172                 if (!CMSG_OK(msg, cmsg))
 173                         return -EINVAL;
 174                 if (cmsg->cmsg_level != SOL_TLS)
 175                         continue;
 176
 177                 switch (cmsg->cmsg_type) {
 178                 case TLS_SET_RECORD_TYPE:
 179                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
 180                                 return -EINVAL;
 181
 182                         if (msg->msg_flags & MSG_MORE)
 183                                 return -EINVAL;
 184
 185                         rc = tls_handle_open_record(sk, msg->msg_flags);
 186                         if (rc)
 187                                 return rc;
 188
 189                         *record_type = *(unsigned char *)CMSG_DATA(cmsg);
 190                         rc = 0;
 191                         break;
 192                 default:
 193                         return -EINVAL;
 194                 }
 195         }
 196
 197         return rc;
 198 }
 199
 200 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
 201                             int flags)
 202 {
 203         struct scatterlist *sg;
 204         u16 offset;
 205
 206         sg = ctx->partially_sent_record;
 207         offset = ctx->partially_sent_offset;
 208
 209         ctx->partially_sent_record = NULL;
 210         return tls_push_sg(sk, ctx, sg, offset, flags);
 211 }
 212
 213 void tls_free_partial_record(struct sock *sk, struct tls_context *ctx)
 214 {
 215         struct scatterlist *sg;
 216
 217         for (sg = ctx->partially_sent_record; sg; sg = sg_next(sg)) {
 218                 put_page(sg_page(sg));
 219                 sk_mem_uncharge(sk, sg->length);
 220         }
 221         ctx->partially_sent_record = NULL;
 222 }
 223
 224 static void tls_write_space(struct sock *sk)
 225 {
 226         struct tls_context *ctx = tls_get_ctx(sk);
 227
 228         /* If in_tcp_sendpages call lower protocol write space handler
 229          * to ensure we wake up any waiting operations there. For example
 230          * if do_tcp_sendpages where to call sk_wait_event.
 231          */
 232         if (ctx->in_tcp_sendpages) {
 233                 ctx->sk_write_space(sk);
 234                 return;
 235         }
 236
 237 #ifdef CONFIG_TLS_DEVICE
 238         if (ctx->tx_conf == TLS_HW)
 239                 tls_device_write_space(sk, ctx);
 240         else
 241 #endif
 242                 tls_sw_write_space(sk, ctx);
 243
 244         ctx->sk_write_space(sk);
 245 }
 246
 247 /**
 248  * tls_ctx_free() - free TLS ULP context
 249  * @sk:  socket to with @ctx is attached
 250  * @ctx: TLS context structure
 251  *
 252  * Free TLS context. If @sk is %NULL caller guarantees that the socket
 253  * to which @ctx was attached has no outstanding references.
 254  */
 255 void tls_ctx_free(struct sock *sk, struct tls_context *ctx)
 256 {
 257         if (!ctx)
 258                 return;
 259
 260         memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
 261         memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
 262         mutex_destroy(&ctx->tx_lock);
 263
 264         if (sk)
 265                 kfree_rcu(ctx, rcu);
 266         else
 267                 kfree(ctx);
 268 }
 269
 270 static void tls_sk_proto_cleanup(struct sock *sk,
 271                                  struct tls_context *ctx, long timeo)
 272 {
 273         if (unlikely(sk->sk_write_pending) &&
 274             !wait_on_pending_writer(sk, &timeo))
 275                 tls_handle_open_record(sk, 0);
 276
 277         /* We need these for tls_sw_fallback handling of other packets */
 278         if (ctx->tx_conf == TLS_SW) {
 279                 kfree(ctx->tx.rec_seq);
 280                 kfree(ctx->tx.iv);
 281                 tls_sw_release_resources_tx(sk);
 282                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 283         } else if (ctx->tx_conf == TLS_HW) {
 284                 tls_device_free_resources_tx(sk);
 285                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
 286         }
 287
 288         if (ctx->rx_conf == TLS_SW) {
 289                 tls_sw_release_resources_rx(sk);
 290                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
 291         } else if (ctx->rx_conf == TLS_HW) {
 292                 tls_device_offload_cleanup_rx(sk);
 293                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
 294         }
 295 }
 296
 297 static void tls_sk_proto_close(struct sock *sk, long timeout)
 298 {
 299         struct inet_connection_sock *icsk = inet_csk(sk);
 300         struct tls_context *ctx = tls_get_ctx(sk);
 301         long timeo = sock_sndtimeo(sk, 0);
 302         bool free_ctx;
 303
 304         if (ctx->tx_conf == TLS_SW)
 305                 tls_sw_cancel_work_tx(ctx);
 306
 307         lock_sock(sk);
 308         free_ctx = ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW;
 309
 310         if (ctx->tx_conf != TLS_BASE || ctx->rx_conf != TLS_BASE)
 311                 tls_sk_proto_cleanup(sk, ctx, timeo);
 312
 313         write_lock_bh(&sk->sk_callback_lock);
 314         if (free_ctx)
 315                 rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
 316         WRITE_ONCE(sk->sk_prot, ctx->sk_proto);
 317         if (sk->sk_write_space == tls_write_space)
 318                 sk->sk_write_space = ctx->sk_write_space;
 319         write_unlock_bh(&sk->sk_callback_lock);
 320         release_sock(sk);
 321         if (ctx->tx_conf == TLS_SW)
 322                 tls_sw_free_ctx_tx(ctx);
 323         if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
 324                 tls_sw_strparser_done(ctx);
 325         if (ctx->rx_conf == TLS_SW)
 326                 tls_sw_free_ctx_rx(ctx);
 327         ctx->sk_proto->close(sk, timeout);
 328
 329         if (free_ctx)
 330                 tls_ctx_free(sk, ctx);
 331 }
 332
 333 static int do_tls_getsockopt_conf(struct sock *sk, char __user *optval,
 334                                   int __user *optlen, int tx)
 335 {
 336         int rc = 0;
 337         struct tls_context *ctx = tls_get_ctx(sk);
 338         struct tls_crypto_info *crypto_info;
 339         struct cipher_context *cctx;
 340         int len;
 341
 342         if (get_user(len, optlen))
 343                 return -EFAULT;
 344
 345         if (!optval || (len < sizeof(*crypto_info))) {
 346                 rc = -EINVAL;
 347                 goto out;
 348         }
 349
 350         if (!ctx) {
 351                 rc = -EBUSY;
 352                 goto out;
 353         }
 354
 355         /* get user crypto info */
 356         if (tx) {
 357                 crypto_info = &ctx->crypto_send.info;
 358                 cctx = &ctx->tx;
 359         } else {
 360                 crypto_info = &ctx->crypto_recv.info;
 361                 cctx = &ctx->rx;
 362         }
 363
 364         if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
 365                 rc = -EBUSY;
 366                 goto out;
 367         }
 368
 369         if (len == sizeof(*crypto_info)) {
 370                 if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
 371                         rc = -EFAULT;
 372                 goto out;
 373         }
 374
 375         switch (crypto_info->cipher_type) {
 376         case TLS_CIPHER_AES_GCM_128: {
 377                 struct tls12_crypto_info_aes_gcm_128 *
 378                   crypto_info_aes_gcm_128 =
 379                   container_of(crypto_info,
 380                                struct tls12_crypto_info_aes_gcm_128,
 381                                info);
 382
 383                 if (len != sizeof(*crypto_info_aes_gcm_128)) {
 384                         rc = -EINVAL;
 385                         goto out;
 386                 }
 387                 lock_sock(sk);
 388                 memcpy(crypto_info_aes_gcm_128->iv,
 389                        cctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
 390                        TLS_CIPHER_AES_GCM_128_IV_SIZE);
 391                 memcpy(crypto_info_aes_gcm_128->rec_seq, cctx->rec_seq,
 392                        TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
 393                 release_sock(sk);
 394                 if (copy_to_user(optval,
 395                                  crypto_info_aes_gcm_128,
 396                                  sizeof(*crypto_info_aes_gcm_128)))
 397                         rc = -EFAULT;
 398                 break;
 399         }
 400         case TLS_CIPHER_AES_GCM_256: {
 401                 struct tls12_crypto_info_aes_gcm_256 *
 402                   crypto_info_aes_gcm_256 =
 403                   container_of(crypto_info,
 404                                struct tls12_crypto_info_aes_gcm_256,
 405                                info);
 406
 407                 if (len != sizeof(*crypto_info_aes_gcm_256)) {
 408                         rc = -EINVAL;
 409                         goto out;
 410                 }
 411                 lock_sock(sk);
 412                 memcpy(crypto_info_aes_gcm_256->iv,
 413                        cctx->iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
 414                        TLS_CIPHER_AES_GCM_256_IV_SIZE);
 415                 memcpy(crypto_info_aes_gcm_256->rec_seq, cctx->rec_seq,
 416                        TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
 417                 release_sock(sk);
 418                 if (copy_to_user(optval,
 419                                  crypto_info_aes_gcm_256,
 420                                  sizeof(*crypto_info_aes_gcm_256)))
 421                         rc = -EFAULT;
 422                 break;
 423         }
 424         default:
 425                 rc = -EINVAL;
 426         }
 427
 428 out:
 429         return rc;
 430 }
 431
 432 static int do_tls_getsockopt(struct sock *sk, int optname,
 433                              char __user *optval, int __user *optlen)
 434 {
 435         int rc = 0;
 436
 437         switch (optname) {
 438         case TLS_TX:
 439         case TLS_RX:
 440                 rc = do_tls_getsockopt_conf(sk, optval, optlen,
 441                                             optname == TLS_TX);
 442                 break;
 443         default:
 444                 rc = -ENOPROTOOPT;
 445                 break;
 446         }
 447         return rc;
 448 }
 449
 450 static int tls_getsockopt(struct sock *sk, int level, int optname,
 451                           char __user *optval, int __user *optlen)
 452 {
 453         struct tls_context *ctx = tls_get_ctx(sk);
 454
 455         if (level != SOL_TLS)
 456                 return ctx->sk_proto->getsockopt(sk, level,
 457                                                  optname, optval, optlen);
 458
 459         return do_tls_getsockopt(sk, optname, optval, optlen);
 460 }
 461
 462 static int do_tls_setsockopt_conf(struct sock *sk, sockptr_t optval,
 463                                   unsigned int optlen, int tx)
 464 {
 465         struct tls_crypto_info *crypto_info;
 466         struct tls_crypto_info *alt_crypto_info;
 467         struct tls_context *ctx = tls_get_ctx(sk);
 468         size_t optsize;
 469         int rc = 0;
 470         int conf;
 471
 472         if (sockptr_is_null(optval) || (optlen < sizeof(*crypto_info))) {
 473                 rc = -EINVAL;
 474                 goto out;
 475         }
 476
 477         if (tx) {
 478                 crypto_info = &ctx->crypto_send.info;
 479                 alt_crypto_info = &ctx->crypto_recv.info;
 480         } else {
 481                 crypto_info = &ctx->crypto_recv.info;
 482                 alt_crypto_info = &ctx->crypto_send.info;
 483         }
 484
 485         /* Currently we don't support set crypto info more than one time */
 486         if (TLS_CRYPTO_INFO_READY(crypto_info)) {
 487                 rc = -EBUSY;
 488                 goto out;
 489         }
 490
 491         rc = copy_from_sockptr(crypto_info, optval, sizeof(*crypto_info));
 492         if (rc) {
 493                 rc = -EFAULT;
 494                 goto err_crypto_info;
 495         }
 496
 497         /* check version */
 498         if (crypto_info->version != TLS_1_2_VERSION &&
 499             crypto_info->version != TLS_1_3_VERSION) {
 500                 rc = -EINVAL;
 501                 goto err_crypto_info;
 502         }
 503
 504         /* Ensure that TLS version and ciphers are same in both directions */
 505         if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
 506                 if (alt_crypto_info->version != crypto_info->version ||
 507                     alt_crypto_info->cipher_type != crypto_info->cipher_type) {
 508                         rc = -EINVAL;
 509                         goto err_crypto_info;
 510                 }
 511         }
 512
 513         switch (crypto_info->cipher_type) {
 514         case TLS_CIPHER_AES_GCM_128:
 515                 optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
 516                 break;
 517         case TLS_CIPHER_AES_GCM_256: {
 518                 optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
 519                 break;
 520         }
 521         case TLS_CIPHER_AES_CCM_128:
 522                 optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
 523                 break;
 524         case TLS_CIPHER_CHACHA20_POLY1305:
 525                 optsize = sizeof(struct tls12_crypto_info_chacha20_poly1305);
 526                 break;
 527         default:
 528                 rc = -EINVAL;
 529                 goto err_crypto_info;
 530         }
 531
 532         if (optlen != optsize) {
 533                 rc = -EINVAL;
 534                 goto err_crypto_info;
 535         }
 536
 537         rc = copy_from_sockptr_offset(crypto_info + 1, optval,
 538                                       sizeof(*crypto_info),
 539                                       optlen - sizeof(*crypto_info));
 540         if (rc) {
 541                 rc = -EFAULT;
 542                 goto err_crypto_info;
 543         }
 544
 545         if (tx) {
 546                 rc = tls_set_device_offload(sk, ctx);
 547                 conf = TLS_HW;
 548                 if (!rc) {
 549                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
 550                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
 551                 } else {
 552                         rc = tls_set_sw_offload(sk, ctx, 1);
 553                         if (rc)
 554                                 goto err_crypto_info;
 555                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
 556                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 557                         conf = TLS_SW;
 558                 }
 559         } else {
 560                 rc = tls_set_device_offload_rx(sk, ctx);
 561                 conf = TLS_HW;
 562                 if (!rc) {
 563                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
 564                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
 565                 } else {
 566                         rc = tls_set_sw_offload(sk, ctx, 0);
 567                         if (rc)
 568                                 goto err_crypto_info;
 569                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
 570                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
 571                         conf = TLS_SW;
 572                 }
 573                 tls_sw_strparser_arm(sk, ctx);
 574         }
 575
 576         if (tx)
 577                 ctx->tx_conf = conf;
 578         else
 579                 ctx->rx_conf = conf;
 580         update_sk_prot(sk, ctx);
 581         if (tx) {
 582                 ctx->sk_write_space = sk->sk_write_space;
 583                 sk->sk_write_space = tls_write_space;
 584         } else {
 585                 sk->sk_socket->ops = &tls_sw_proto_ops;
 586         }
 587         goto out;
 588
 589 err_crypto_info:
 590         memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
 591 out:
 592         return rc;
 593 }
 594
 595 static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval,
 596                              unsigned int optlen)
 597 {
 598         int rc = 0;
 599
 600         switch (optname) {
 601         case TLS_TX:
 602         case TLS_RX:
 603                 lock_sock(sk);
 604                 rc = do_tls_setsockopt_conf(sk, optval, optlen,
 605                                             optname == TLS_TX);
 606                 release_sock(sk);
 607                 break;
 608         default:
 609                 rc = -ENOPROTOOPT;
 610                 break;
 611         }
 612         return rc;
 613 }
 614
 615 static int tls_setsockopt(struct sock *sk, int level, int optname,
 616                           sockptr_t optval, unsigned int optlen)
 617 {
 618         struct tls_context *ctx = tls_get_ctx(sk);
 619
 620         if (level != SOL_TLS)
 621                 return ctx->sk_proto->setsockopt(sk, level, optname, optval,
 622                                                  optlen);
 623
 624         return do_tls_setsockopt(sk, optname, optval, optlen);
 625 }
 626
 627 struct tls_context *tls_ctx_create(struct sock *sk)
 628 {
 629         struct inet_connection_sock *icsk = inet_csk(sk);
 630         struct tls_context *ctx;
 631
 632         ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
 633         if (!ctx)
 634                 return NULL;
 635
 636         mutex_init(&ctx->tx_lock);
 637         rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
 638         ctx->sk_proto = READ_ONCE(sk->sk_prot);
 639         return ctx;
 640 }
 641
 642 static void tls_build_proto(struct sock *sk)
 643 {
 644         int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
 645         struct proto *prot = READ_ONCE(sk->sk_prot);
 646
 647         /* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
 648         if (ip_ver == TLSV6 &&
 649             unlikely(prot != smp_load_acquire(&saved_tcpv6_prot))) {
 650                 mutex_lock(&tcpv6_prot_mutex);
 651                 if (likely(prot != saved_tcpv6_prot)) {
 652                         build_protos(tls_prots[TLSV6], prot);
 653                         smp_store_release(&saved_tcpv6_prot, prot);
 654                 }
 655                 mutex_unlock(&tcpv6_prot_mutex);
 656         }
 657
 658         if (ip_ver == TLSV4 &&
 659             unlikely(prot != smp_load_acquire(&saved_tcpv4_prot))) {
 660                 mutex_lock(&tcpv4_prot_mutex);
 661                 if (likely(prot != saved_tcpv4_prot)) {
 662                         build_protos(tls_prots[TLSV4], prot);
 663                         smp_store_release(&saved_tcpv4_prot, prot);
 664                 }
 665                 mutex_unlock(&tcpv4_prot_mutex);
 666         }
 667 }
 668
 669 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
 670                          const struct proto *base)
 671 {
 672         prot[TLS_BASE][TLS_BASE] = *base;
 673         prot[TLS_BASE][TLS_BASE].setsockopt     = tls_setsockopt;
 674         prot[TLS_BASE][TLS_BASE].getsockopt     = tls_getsockopt;
 675         prot[TLS_BASE][TLS_BASE].close          = tls_sk_proto_close;
 676
 677         prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 678         prot[TLS_SW][TLS_BASE].sendmsg          = tls_sw_sendmsg;
 679         prot[TLS_SW][TLS_BASE].sendpage         = tls_sw_sendpage;
 680
 681         prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
 682         prot[TLS_BASE][TLS_SW].recvmsg            = tls_sw_recvmsg;
 683         prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
 684         prot[TLS_BASE][TLS_SW].close              = tls_sk_proto_close;
 685
 686         prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
 687         prot[TLS_SW][TLS_SW].recvmsg            = tls_sw_recvmsg;
 688         prot[TLS_SW][TLS_SW].stream_memory_read = tls_sw_stream_read;
 689         prot[TLS_SW][TLS_SW].close              = tls_sk_proto_close;
 690
 691 #ifdef CONFIG_TLS_DEVICE
 692         prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 693         prot[TLS_HW][TLS_BASE].sendmsg          = tls_device_sendmsg;
 694         prot[TLS_HW][TLS_BASE].sendpage         = tls_device_sendpage;
 695
 696         prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
 697         prot[TLS_HW][TLS_SW].sendmsg            = tls_device_sendmsg;
 698         prot[TLS_HW][TLS_SW].sendpage           = tls_device_sendpage;
 699
 700         prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
 701
 702         prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
 703
 704         prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
 705 #endif
 706 #ifdef CONFIG_TLS_TOE
 707         prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
 708         prot[TLS_HW_RECORD][TLS_HW_RECORD].hash         = tls_toe_hash;
 709         prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash       = tls_toe_unhash;
 710 #endif
 711 }
 712
 713 static int tls_init(struct sock *sk)
 714 {
 715         struct tls_context *ctx;
 716         int rc = 0;
 717
 718         tls_build_proto(sk);
 719
 720 #ifdef CONFIG_TLS_TOE
 721         if (tls_toe_bypass(sk))
 722                 return 0;
 723 #endif
 724
 725         /* The TLS ulp is currently supported only for TCP sockets
 726          * in ESTABLISHED state.
 727          * Supporting sockets in LISTEN state will require us
 728          * to modify the accept implementation to clone rather then
 729          * share the ulp context.
 730          */
 731         if (sk->sk_state != TCP_ESTABLISHED)
 732                 return -ENOTCONN;
 733
 734         /* allocate tls context */
 735         write_lock_bh(&sk->sk_callback_lock);
 736         ctx = tls_ctx_create(sk);
 737         if (!ctx) {
 738                 rc = -ENOMEM;
 739                 goto out;
 740         }
 741
 742         ctx->tx_conf = TLS_BASE;
 743         ctx->rx_conf = TLS_BASE;
 744         update_sk_prot(sk, ctx);
 745 out:
 746         write_unlock_bh(&sk->sk_callback_lock);
 747         return rc;
 748 }
 749
 750 static void tls_update(struct sock *sk, struct proto *p,
 751                        void (*write_space)(struct sock *sk))
 752 {
 753         struct tls_context *ctx;
 754
 755         ctx = tls_get_ctx(sk);
 756         if (likely(ctx)) {
 757                 ctx->sk_write_space = write_space;
 758                 ctx->sk_proto = p;
 759         } else {
 760                 /* Pairs with lockless read in sk_clone_lock(). */
 761                 WRITE_ONCE(sk->sk_prot, p);
 762                 sk->sk_write_space = write_space;
 763         }
 764 }
 765
 766 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
 767 {
 768         u16 version, cipher_type;
 769         struct tls_context *ctx;
 770         struct nlattr *start;
 771         int err;
 772
 773         start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
 774         if (!start)
 775                 return -EMSGSIZE;
 776
 777         rcu_read_lock();
 778         ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
 779         if (!ctx) {
 780                 err = 0;
 781                 goto nla_failure;
 782         }
 783         version = ctx->prot_info.version;
 784         if (version) {
 785                 err = nla_put_u16(skb, TLS_INFO_VERSION, version);
 786                 if (err)
 787                         goto nla_failure;
 788         }
 789         cipher_type = ctx->prot_info.cipher_type;
 790         if (cipher_type) {
 791                 err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
 792                 if (err)
 793                         goto nla_failure;
 794         }
 795         err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
 796         if (err)
 797                 goto nla_failure;
 798
 799         err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
 800         if (err)
 801                 goto nla_failure;
 802
 803         rcu_read_unlock();
 804         nla_nest_end(skb, start);
 805         return 0;
 806
 807 nla_failure:
 808         rcu_read_unlock();
 809         nla_nest_cancel(skb, start);
 810         return err;
 811 }
 812
 813 static size_t tls_get_info_size(const struct sock *sk)
 814 {
 815         size_t size = 0;
 816
 817         size += nla_total_size(0) +             /* INET_ULP_INFO_TLS */
 818                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_VERSION */
 819                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_CIPHER */
 820                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_RXCONF */
 821                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_TXCONF */
 822                 0;
 823
 824         return size;
 825 }
 826
 827 static int __net_init tls_init_net(struct net *net)
 828 {
 829         int err;
 830
 831         net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
 832         if (!net->mib.tls_statistics)
 833                 return -ENOMEM;
 834
 835         err = tls_proc_init(net);
 836         if (err)
 837                 goto err_free_stats;
 838
 839         return 0;
 840 err_free_stats:
 841         free_percpu(net->mib.tls_statistics);
 842         return err;
 843 }
 844
 845 static void __net_exit tls_exit_net(struct net *net)
 846 {
 847         tls_proc_fini(net);
 848         free_percpu(net->mib.tls_statistics);
 849 }
 850
 851 static struct pernet_operations tls_proc_ops = {
 852         .init = tls_init_net,
 853         .exit = tls_exit_net,
 854 };
 855
 856 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
 857         .name                   = "tls",
 858         .owner                  = THIS_MODULE,
 859         .init                   = tls_init,
 860         .update                 = tls_update,
 861         .get_info               = tls_get_info,
 862         .get_info_size          = tls_get_info_size,
 863 };
 864
 865 static int __init tls_register(void)
 866 {
 867         int err;
 868
 869         err = register_pernet_subsys(&tls_proc_ops);
 870         if (err)
 871                 return err;
 872
 873         tls_sw_proto_ops = inet_stream_ops;
 874         tls_sw_proto_ops.splice_read = tls_sw_splice_read;
 875         tls_sw_proto_ops.sendpage_locked   = tls_sw_sendpage_locked;
 876
 877         tls_device_init();
 878         tcp_register_ulp(&tcp_tls_ulp_ops);
 879
 880         return 0;
 881 }
 882
 883 static void __exit tls_unregister(void)
 884 {
 885         tcp_unregister_ulp(&tcp_tls_ulp_ops);
 886         tls_device_cleanup();
 887         unregister_pernet_subsys(&tls_proc_ops);
 888 }
 889
 890 module_init(tls_register);
 891 module_exit(tls_unregister);