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/tls.h>
  45
  46 MODULE_AUTHOR("Mellanox Technologies");
  47 MODULE_DESCRIPTION("Transport Layer Security Support");
  48 MODULE_LICENSE("Dual BSD/GPL");
  49 MODULE_ALIAS_TCP_ULP("tls");
  50
  51 enum {
  52         TLSV4,
  53         TLSV6,
  54         TLS_NUM_PROTS,
  55 };
  56
  57 static struct proto *saved_tcpv6_prot;
  58 static DEFINE_MUTEX(tcpv6_prot_mutex);
  59 static struct proto *saved_tcpv4_prot;
  60 static DEFINE_MUTEX(tcpv4_prot_mutex);
  61 static LIST_HEAD(device_list);
  62 static DEFINE_SPINLOCK(device_spinlock);
  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                          struct proto *base);
  67
  68 static 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         sk->sk_prot = &tls_prots[ip_ver][ctx->tx_conf][ctx->rx_conf];
  73 }
  74
  75 int wait_on_pending_writer(struct sock *sk, long *timeo)
  76 {
  77         int rc = 0;
  78         DEFINE_WAIT_FUNC(wait, woken_wake_function);
  79
  80         add_wait_queue(sk_sleep(sk), &wait);
  81         while (1) {
  82                 if (!*timeo) {
  83                         rc = -EAGAIN;
  84                         break;
  85                 }
  86
  87                 if (signal_pending(current)) {
  88                         rc = sock_intr_errno(*timeo);
  89                         break;
  90                 }
  91
  92                 if (sk_wait_event(sk, timeo, !sk->sk_write_pending, &wait))
  93                         break;
  94         }
  95         remove_wait_queue(sk_sleep(sk), &wait);
  96         return rc;
  97 }
  98
  99 int tls_push_sg(struct sock *sk,
 100                 struct tls_context *ctx,
 101                 struct scatterlist *sg,
 102                 u16 first_offset,
 103                 int flags)
 104 {
 105         int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
 106         int ret = 0;
 107         struct page *p;
 108         size_t size;
 109         int offset = first_offset;
 110
 111         size = sg->length - offset;
 112         offset += sg->offset;
 113
 114         ctx->in_tcp_sendpages = true;
 115         while (1) {
 116                 if (sg_is_last(sg))
 117                         sendpage_flags = flags;
 118
 119                 /* is sending application-limited? */
 120                 tcp_rate_check_app_limited(sk);
 121                 p = sg_page(sg);
 122 retry:
 123                 ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
 124
 125                 if (ret != size) {
 126                         if (ret > 0) {
 127                                 offset += ret;
 128                                 size -= ret;
 129                                 goto retry;
 130                         }
 131
 132                         offset -= sg->offset;
 133                         ctx->partially_sent_offset = offset;
 134                         ctx->partially_sent_record = (void *)sg;
 135                         ctx->in_tcp_sendpages = false;
 136                         return ret;
 137                 }
 138
 139                 put_page(p);
 140                 sk_mem_uncharge(sk, sg->length);
 141                 sg = sg_next(sg);
 142                 if (!sg)
 143                         break;
 144
 145                 offset = sg->offset;
 146                 size = sg->length;
 147         }
 148
 149         ctx->in_tcp_sendpages = false;
 150
 151         return 0;
 152 }
 153
 154 static int tls_handle_open_record(struct sock *sk, int flags)
 155 {
 156         struct tls_context *ctx = tls_get_ctx(sk);
 157
 158         if (tls_is_pending_open_record(ctx))
 159                 return ctx->push_pending_record(sk, flags);
 160
 161         return 0;
 162 }
 163
 164 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
 165                       unsigned char *record_type)
 166 {
 167         struct cmsghdr *cmsg;
 168         int rc = -EINVAL;
 169
 170         for_each_cmsghdr(cmsg, msg) {
 171                 if (!CMSG_OK(msg, cmsg))
 172                         return -EINVAL;
 173                 if (cmsg->cmsg_level != SOL_TLS)
 174                         continue;
 175
 176                 switch (cmsg->cmsg_type) {
 177                 case TLS_SET_RECORD_TYPE:
 178                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
 179                                 return -EINVAL;
 180
 181                         if (msg->msg_flags & MSG_MORE)
 182                                 return -EINVAL;
 183
 184                         rc = tls_handle_open_record(sk, msg->msg_flags);
 185                         if (rc)
 186                                 return rc;
 187
 188                         *record_type = *(unsigned char *)CMSG_DATA(cmsg);
 189                         rc = 0;
 190                         break;
 191                 default:
 192                         return -EINVAL;
 193                 }
 194         }
 195
 196         return rc;
 197 }
 198
 199 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
 200                             int flags)
 201 {
 202         struct scatterlist *sg;
 203         u16 offset;
 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 bool tls_free_partial_record(struct sock *sk, struct tls_context *ctx)
 213 {
 214         struct scatterlist *sg;
 215
 216         sg = ctx->partially_sent_record;
 217         if (!sg)
 218                 return false;
 219
 220         while (1) {
 221                 put_page(sg_page(sg));
 222                 sk_mem_uncharge(sk, sg->length);
 223
 224                 if (sg_is_last(sg))
 225                         break;
 226                 sg++;
 227         }
 228         ctx->partially_sent_record = NULL;
 229         return true;
 230 }
 231
 232 static void tls_write_space(struct sock *sk)
 233 {
 234         struct tls_context *ctx = tls_get_ctx(sk);
 235
 236         /* If in_tcp_sendpages call lower protocol write space handler
 237          * to ensure we wake up any waiting operations there. For example
 238          * if do_tcp_sendpages where to call sk_wait_event.
 239          */
 240         if (ctx->in_tcp_sendpages) {
 241                 ctx->sk_write_space(sk);
 242                 return;
 243         }
 244
 245 #ifdef CONFIG_TLS_DEVICE
 246         if (ctx->tx_conf == TLS_HW)
 247                 tls_device_write_space(sk, ctx);
 248         else
 249 #endif
 250                 tls_sw_write_space(sk, ctx);
 251
 252         ctx->sk_write_space(sk);
 253 }
 254
 255 /**
 256  * tls_ctx_free() - free TLS ULP context
 257  * @sk:  socket to with @ctx is attached
 258  * @ctx: TLS context structure
 259  *
 260  * Free TLS context. If @sk is %NULL caller guarantees that the socket
 261  * to which @ctx was attached has no outstanding references.
 262  */
 263 void tls_ctx_free(struct sock *sk, struct tls_context *ctx)
 264 {
 265         if (!ctx)
 266                 return;
 267
 268         memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
 269         memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
 270
 271         if (sk)
 272                 kfree_rcu(ctx, rcu);
 273         else
 274                 kfree(ctx);
 275 }
 276
 277 static void tls_sk_proto_cleanup(struct sock *sk,
 278                                  struct tls_context *ctx, long timeo)
 279 {
 280         if (unlikely(sk->sk_write_pending) &&
 281             !wait_on_pending_writer(sk, &timeo))
 282                 tls_handle_open_record(sk, 0);
 283
 284         /* We need these for tls_sw_fallback handling of other packets */
 285         if (ctx->tx_conf == TLS_SW) {
 286                 kfree(ctx->tx.rec_seq);
 287                 kfree(ctx->tx.iv);
 288                 tls_sw_release_resources_tx(sk);
 289         } else if (ctx->tx_conf == TLS_HW) {
 290                 tls_device_free_resources_tx(sk);
 291         }
 292
 293         if (ctx->rx_conf == TLS_SW)
 294                 tls_sw_release_resources_rx(sk);
 295         else if (ctx->rx_conf == TLS_HW)
 296                 tls_device_offload_cleanup_rx(sk);
 297 }
 298
 299 static void tls_sk_proto_close(struct sock *sk, long timeout)
 300 {
 301         struct inet_connection_sock *icsk = inet_csk(sk);
 302         struct tls_context *ctx = tls_get_ctx(sk);
 303         long timeo = sock_sndtimeo(sk, 0);
 304         bool free_ctx;
 305
 306         if (ctx->tx_conf == TLS_SW)
 307                 tls_sw_cancel_work_tx(ctx);
 308
 309         lock_sock(sk);
 310         free_ctx = ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW;
 311
 312         if (ctx->tx_conf != TLS_BASE || ctx->rx_conf != TLS_BASE)
 313                 tls_sk_proto_cleanup(sk, ctx, timeo);
 314
 315         write_lock_bh(&sk->sk_callback_lock);
 316         if (free_ctx)
 317                 rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
 318         sk->sk_prot = ctx->sk_proto;
 319         if (sk->sk_write_space == tls_write_space)
 320                 sk->sk_write_space = ctx->sk_write_space;
 321         write_unlock_bh(&sk->sk_callback_lock);
 322         release_sock(sk);
 323         if (ctx->tx_conf == TLS_SW)
 324                 tls_sw_free_ctx_tx(ctx);
 325         if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
 326                 tls_sw_strparser_done(ctx);
 327         if (ctx->rx_conf == TLS_SW)
 328                 tls_sw_free_ctx_rx(ctx);
 329         ctx->sk_proto->close(sk, timeout);
 330
 331         if (free_ctx)
 332                 tls_ctx_free(sk, ctx);
 333 }
 334
 335 static int do_tls_getsockopt_tx(struct sock *sk, char __user *optval,
 336                                 int __user *optlen)
 337 {
 338         int rc = 0;
 339         struct tls_context *ctx = tls_get_ctx(sk);
 340         struct tls_crypto_info *crypto_info;
 341         int len;
 342
 343         if (get_user(len, optlen))
 344                 return -EFAULT;
 345
 346         if (!optval || (len < sizeof(*crypto_info))) {
 347                 rc = -EINVAL;
 348                 goto out;
 349         }
 350
 351         if (!ctx) {
 352                 rc = -EBUSY;
 353                 goto out;
 354         }
 355
 356         /* get user crypto info */
 357         crypto_info = &ctx->crypto_send.info;
 358
 359         if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
 360                 rc = -EBUSY;
 361                 goto out;
 362         }
 363
 364         if (len == sizeof(*crypto_info)) {
 365                 if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
 366                         rc = -EFAULT;
 367                 goto out;
 368         }
 369
 370         switch (crypto_info->cipher_type) {
 371         case TLS_CIPHER_AES_GCM_128: {
 372                 struct tls12_crypto_info_aes_gcm_128 *
 373                   crypto_info_aes_gcm_128 =
 374                   container_of(crypto_info,
 375                                struct tls12_crypto_info_aes_gcm_128,
 376                                info);
 377
 378                 if (len != sizeof(*crypto_info_aes_gcm_128)) {
 379                         rc = -EINVAL;
 380                         goto out;
 381                 }
 382                 lock_sock(sk);
 383                 memcpy(crypto_info_aes_gcm_128->iv,
 384                        ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
 385                        TLS_CIPHER_AES_GCM_128_IV_SIZE);
 386                 memcpy(crypto_info_aes_gcm_128->rec_seq, ctx->tx.rec_seq,
 387                        TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
 388                 release_sock(sk);
 389                 if (copy_to_user(optval,
 390                                  crypto_info_aes_gcm_128,
 391                                  sizeof(*crypto_info_aes_gcm_128)))
 392                         rc = -EFAULT;
 393                 break;
 394         }
 395         case TLS_CIPHER_AES_GCM_256: {
 396                 struct tls12_crypto_info_aes_gcm_256 *
 397                   crypto_info_aes_gcm_256 =
 398                   container_of(crypto_info,
 399                                struct tls12_crypto_info_aes_gcm_256,
 400                                info);
 401
 402                 if (len != sizeof(*crypto_info_aes_gcm_256)) {
 403                         rc = -EINVAL;
 404                         goto out;
 405                 }
 406                 lock_sock(sk);
 407                 memcpy(crypto_info_aes_gcm_256->iv,
 408                        ctx->tx.iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
 409                        TLS_CIPHER_AES_GCM_256_IV_SIZE);
 410                 memcpy(crypto_info_aes_gcm_256->rec_seq, ctx->tx.rec_seq,
 411                        TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
 412                 release_sock(sk);
 413                 if (copy_to_user(optval,
 414                                  crypto_info_aes_gcm_256,
 415                                  sizeof(*crypto_info_aes_gcm_256)))
 416                         rc = -EFAULT;
 417                 break;
 418         }
 419         default:
 420                 rc = -EINVAL;
 421         }
 422
 423 out:
 424         return rc;
 425 }
 426
 427 static int do_tls_getsockopt(struct sock *sk, int optname,
 428                              char __user *optval, int __user *optlen)
 429 {
 430         int rc = 0;
 431
 432         switch (optname) {
 433         case TLS_TX:
 434                 rc = do_tls_getsockopt_tx(sk, optval, optlen);
 435                 break;
 436         default:
 437                 rc = -ENOPROTOOPT;
 438                 break;
 439         }
 440         return rc;
 441 }
 442
 443 static int tls_getsockopt(struct sock *sk, int level, int optname,
 444                           char __user *optval, int __user *optlen)
 445 {
 446         struct tls_context *ctx = tls_get_ctx(sk);
 447
 448         if (level != SOL_TLS)
 449                 return ctx->sk_proto->getsockopt(sk, level,
 450                                                  optname, optval, optlen);
 451
 452         return do_tls_getsockopt(sk, optname, optval, optlen);
 453 }
 454
 455 static int do_tls_setsockopt_conf(struct sock *sk, char __user *optval,
 456                                   unsigned int optlen, int tx)
 457 {
 458         struct tls_crypto_info *crypto_info;
 459         struct tls_crypto_info *alt_crypto_info;
 460         struct tls_context *ctx = tls_get_ctx(sk);
 461         size_t optsize;
 462         int rc = 0;
 463         int conf;
 464
 465         if (!optval || (optlen < sizeof(*crypto_info))) {
 466                 rc = -EINVAL;
 467                 goto out;
 468         }
 469
 470         if (tx) {
 471                 crypto_info = &ctx->crypto_send.info;
 472                 alt_crypto_info = &ctx->crypto_recv.info;
 473         } else {
 474                 crypto_info = &ctx->crypto_recv.info;
 475                 alt_crypto_info = &ctx->crypto_send.info;
 476         }
 477
 478         /* Currently we don't support set crypto info more than one time */
 479         if (TLS_CRYPTO_INFO_READY(crypto_info)) {
 480                 rc = -EBUSY;
 481                 goto out;
 482         }
 483
 484         rc = copy_from_user(crypto_info, optval, sizeof(*crypto_info));
 485         if (rc) {
 486                 rc = -EFAULT;
 487                 goto err_crypto_info;
 488         }
 489
 490         /* check version */
 491         if (crypto_info->version != TLS_1_2_VERSION &&
 492             crypto_info->version != TLS_1_3_VERSION) {
 493                 rc = -ENOTSUPP;
 494                 goto err_crypto_info;
 495         }
 496
 497         /* Ensure that TLS version and ciphers are same in both directions */
 498         if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
 499                 if (alt_crypto_info->version != crypto_info->version ||
 500                     alt_crypto_info->cipher_type != crypto_info->cipher_type) {
 501                         rc = -EINVAL;
 502                         goto err_crypto_info;
 503                 }
 504         }
 505
 506         switch (crypto_info->cipher_type) {
 507         case TLS_CIPHER_AES_GCM_128:
 508                 optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
 509                 break;
 510         case TLS_CIPHER_AES_GCM_256: {
 511                 optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
 512                 break;
 513         }
 514         case TLS_CIPHER_AES_CCM_128:
 515                 optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
 516                 break;
 517         default:
 518                 rc = -EINVAL;
 519                 goto err_crypto_info;
 520         }
 521
 522         if (optlen != optsize) {
 523                 rc = -EINVAL;
 524                 goto err_crypto_info;
 525         }
 526
 527         rc = copy_from_user(crypto_info + 1, optval + sizeof(*crypto_info),
 528                             optlen - sizeof(*crypto_info));
 529         if (rc) {
 530                 rc = -EFAULT;
 531                 goto err_crypto_info;
 532         }
 533
 534         if (tx) {
 535                 rc = tls_set_device_offload(sk, ctx);
 536                 conf = TLS_HW;
 537                 if (rc) {
 538                         rc = tls_set_sw_offload(sk, ctx, 1);
 539                         if (rc)
 540                                 goto err_crypto_info;
 541                         conf = TLS_SW;
 542                 }
 543         } else {
 544                 rc = tls_set_device_offload_rx(sk, ctx);
 545                 conf = TLS_HW;
 546                 if (rc) {
 547                         rc = tls_set_sw_offload(sk, ctx, 0);
 548                         if (rc)
 549                                 goto err_crypto_info;
 550                         conf = TLS_SW;
 551                 }
 552                 tls_sw_strparser_arm(sk, ctx);
 553         }
 554
 555         if (tx)
 556                 ctx->tx_conf = conf;
 557         else
 558                 ctx->rx_conf = conf;
 559         update_sk_prot(sk, ctx);
 560         if (tx) {
 561                 ctx->sk_write_space = sk->sk_write_space;
 562                 sk->sk_write_space = tls_write_space;
 563         } else {
 564                 sk->sk_socket->ops = &tls_sw_proto_ops;
 565         }
 566         goto out;
 567
 568 err_crypto_info:
 569         memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
 570 out:
 571         return rc;
 572 }
 573
 574 static int do_tls_setsockopt(struct sock *sk, int optname,
 575                              char __user *optval, unsigned int optlen)
 576 {
 577         int rc = 0;
 578
 579         switch (optname) {
 580         case TLS_TX:
 581         case TLS_RX:
 582                 lock_sock(sk);
 583                 rc = do_tls_setsockopt_conf(sk, optval, optlen,
 584                                             optname == TLS_TX);
 585                 release_sock(sk);
 586                 break;
 587         default:
 588                 rc = -ENOPROTOOPT;
 589                 break;
 590         }
 591         return rc;
 592 }
 593
 594 static int tls_setsockopt(struct sock *sk, int level, int optname,
 595                           char __user *optval, unsigned int optlen)
 596 {
 597         struct tls_context *ctx = tls_get_ctx(sk);
 598
 599         if (level != SOL_TLS)
 600                 return ctx->sk_proto->setsockopt(sk, level, optname, optval,
 601                                                  optlen);
 602
 603         return do_tls_setsockopt(sk, optname, optval, optlen);
 604 }
 605
 606 static struct tls_context *create_ctx(struct sock *sk)
 607 {
 608         struct inet_connection_sock *icsk = inet_csk(sk);
 609         struct tls_context *ctx;
 610
 611         ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
 612         if (!ctx)
 613                 return NULL;
 614
 615         rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
 616         ctx->sk_proto = sk->sk_prot;
 617         return ctx;
 618 }
 619
 620 static void tls_build_proto(struct sock *sk)
 621 {
 622         int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
 623
 624         /* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
 625         if (ip_ver == TLSV6 &&
 626             unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv6_prot))) {
 627                 mutex_lock(&tcpv6_prot_mutex);
 628                 if (likely(sk->sk_prot != saved_tcpv6_prot)) {
 629                         build_protos(tls_prots[TLSV6], sk->sk_prot);
 630                         smp_store_release(&saved_tcpv6_prot, sk->sk_prot);
 631                 }
 632                 mutex_unlock(&tcpv6_prot_mutex);
 633         }
 634
 635         if (ip_ver == TLSV4 &&
 636             unlikely(sk->sk_prot != smp_load_acquire(&saved_tcpv4_prot))) {
 637                 mutex_lock(&tcpv4_prot_mutex);
 638                 if (likely(sk->sk_prot != saved_tcpv4_prot)) {
 639                         build_protos(tls_prots[TLSV4], sk->sk_prot);
 640                         smp_store_release(&saved_tcpv4_prot, sk->sk_prot);
 641                 }
 642                 mutex_unlock(&tcpv4_prot_mutex);
 643         }
 644 }
 645
 646 static void tls_hw_sk_destruct(struct sock *sk)
 647 {
 648         struct tls_context *ctx = tls_get_ctx(sk);
 649         struct inet_connection_sock *icsk = inet_csk(sk);
 650
 651         ctx->sk_destruct(sk);
 652         /* Free ctx */
 653         rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
 654         tls_ctx_free(sk, ctx);
 655 }
 656
 657 static int tls_hw_prot(struct sock *sk)
 658 {
 659         struct tls_context *ctx;
 660         struct tls_device *dev;
 661         int rc = 0;
 662
 663         spin_lock_bh(&device_spinlock);
 664         list_for_each_entry(dev, &device_list, dev_list) {
 665                 if (dev->feature && dev->feature(dev)) {
 666                         ctx = create_ctx(sk);
 667                         if (!ctx)
 668                                 goto out;
 669
 670                         spin_unlock_bh(&device_spinlock);
 671                         tls_build_proto(sk);
 672                         ctx->sk_destruct = sk->sk_destruct;
 673                         sk->sk_destruct = tls_hw_sk_destruct;
 674                         ctx->rx_conf = TLS_HW_RECORD;
 675                         ctx->tx_conf = TLS_HW_RECORD;
 676                         update_sk_prot(sk, ctx);
 677                         spin_lock_bh(&device_spinlock);
 678                         rc = 1;
 679                         break;
 680                 }
 681         }
 682 out:
 683         spin_unlock_bh(&device_spinlock);
 684         return rc;
 685 }
 686
 687 static void tls_hw_unhash(struct sock *sk)
 688 {
 689         struct tls_context *ctx = tls_get_ctx(sk);
 690         struct tls_device *dev;
 691
 692         spin_lock_bh(&device_spinlock);
 693         list_for_each_entry(dev, &device_list, dev_list) {
 694                 if (dev->unhash) {
 695                         kref_get(&dev->kref);
 696                         spin_unlock_bh(&device_spinlock);
 697                         dev->unhash(dev, sk);
 698                         kref_put(&dev->kref, dev->release);
 699                         spin_lock_bh(&device_spinlock);
 700                 }
 701         }
 702         spin_unlock_bh(&device_spinlock);
 703         ctx->sk_proto->unhash(sk);
 704 }
 705
 706 static int tls_hw_hash(struct sock *sk)
 707 {
 708         struct tls_context *ctx = tls_get_ctx(sk);
 709         struct tls_device *dev;
 710         int err;
 711
 712         err = ctx->sk_proto->hash(sk);
 713         spin_lock_bh(&device_spinlock);
 714         list_for_each_entry(dev, &device_list, dev_list) {
 715                 if (dev->hash) {
 716                         kref_get(&dev->kref);
 717                         spin_unlock_bh(&device_spinlock);
 718                         err |= dev->hash(dev, sk);
 719                         kref_put(&dev->kref, dev->release);
 720                         spin_lock_bh(&device_spinlock);
 721                 }
 722         }
 723         spin_unlock_bh(&device_spinlock);
 724
 725         if (err)
 726                 tls_hw_unhash(sk);
 727         return err;
 728 }
 729
 730 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
 731                          struct proto *base)
 732 {
 733         prot[TLS_BASE][TLS_BASE] = *base;
 734         prot[TLS_BASE][TLS_BASE].setsockopt     = tls_setsockopt;
 735         prot[TLS_BASE][TLS_BASE].getsockopt     = tls_getsockopt;
 736         prot[TLS_BASE][TLS_BASE].close          = tls_sk_proto_close;
 737
 738         prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 739         prot[TLS_SW][TLS_BASE].sendmsg          = tls_sw_sendmsg;
 740         prot[TLS_SW][TLS_BASE].sendpage         = tls_sw_sendpage;
 741
 742         prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
 743         prot[TLS_BASE][TLS_SW].recvmsg            = tls_sw_recvmsg;
 744         prot[TLS_BASE][TLS_SW].stream_memory_read = tls_sw_stream_read;
 745         prot[TLS_BASE][TLS_SW].close              = tls_sk_proto_close;
 746
 747         prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
 748         prot[TLS_SW][TLS_SW].recvmsg            = tls_sw_recvmsg;
 749         prot[TLS_SW][TLS_SW].stream_memory_read = tls_sw_stream_read;
 750         prot[TLS_SW][TLS_SW].close              = tls_sk_proto_close;
 751
 752 #ifdef CONFIG_TLS_DEVICE
 753         prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 754         prot[TLS_HW][TLS_BASE].sendmsg          = tls_device_sendmsg;
 755         prot[TLS_HW][TLS_BASE].sendpage         = tls_device_sendpage;
 756
 757         prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
 758         prot[TLS_HW][TLS_SW].sendmsg            = tls_device_sendmsg;
 759         prot[TLS_HW][TLS_SW].sendpage           = tls_device_sendpage;
 760
 761         prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
 762
 763         prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
 764
 765         prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
 766 #endif
 767
 768         prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
 769         prot[TLS_HW_RECORD][TLS_HW_RECORD].hash         = tls_hw_hash;
 770         prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash       = tls_hw_unhash;
 771 }
 772
 773 static int tls_init(struct sock *sk)
 774 {
 775         struct tls_context *ctx;
 776         int rc = 0;
 777
 778         if (tls_hw_prot(sk))
 779                 return 0;
 780
 781         /* The TLS ulp is currently supported only for TCP sockets
 782          * in ESTABLISHED state.
 783          * Supporting sockets in LISTEN state will require us
 784          * to modify the accept implementation to clone rather then
 785          * share the ulp context.
 786          */
 787         if (sk->sk_state != TCP_ESTABLISHED)
 788                 return -ENOTSUPP;
 789
 790         tls_build_proto(sk);
 791
 792         /* allocate tls context */
 793         write_lock_bh(&sk->sk_callback_lock);
 794         ctx = create_ctx(sk);
 795         if (!ctx) {
 796                 rc = -ENOMEM;
 797                 goto out;
 798         }
 799
 800         ctx->tx_conf = TLS_BASE;
 801         ctx->rx_conf = TLS_BASE;
 802         update_sk_prot(sk, ctx);
 803 out:
 804         write_unlock_bh(&sk->sk_callback_lock);
 805         return rc;
 806 }
 807
 808 static void tls_update(struct sock *sk, struct proto *p)
 809 {
 810         struct tls_context *ctx;
 811
 812         ctx = tls_get_ctx(sk);
 813         if (likely(ctx))
 814                 ctx->sk_proto = p;
 815         else
 816                 sk->sk_prot = p;
 817 }
 818
 819 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
 820 {
 821         u16 version, cipher_type;
 822         struct tls_context *ctx;
 823         struct nlattr *start;
 824         int err;
 825
 826         start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
 827         if (!start)
 828                 return -EMSGSIZE;
 829
 830         rcu_read_lock();
 831         ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
 832         if (!ctx) {
 833                 err = 0;
 834                 goto nla_failure;
 835         }
 836         version = ctx->prot_info.version;
 837         if (version) {
 838                 err = nla_put_u16(skb, TLS_INFO_VERSION, version);
 839                 if (err)
 840                         goto nla_failure;
 841         }
 842         cipher_type = ctx->prot_info.cipher_type;
 843         if (cipher_type) {
 844                 err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
 845                 if (err)
 846                         goto nla_failure;
 847         }
 848         err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
 849         if (err)
 850                 goto nla_failure;
 851
 852         err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
 853         if (err)
 854                 goto nla_failure;
 855
 856         rcu_read_unlock();
 857         nla_nest_end(skb, start);
 858         return 0;
 859
 860 nla_failure:
 861         rcu_read_unlock();
 862         nla_nest_cancel(skb, start);
 863         return err;
 864 }
 865
 866 static size_t tls_get_info_size(const struct sock *sk)
 867 {
 868         size_t size = 0;
 869
 870         size += nla_total_size(0) +             /* INET_ULP_INFO_TLS */
 871                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_VERSION */
 872                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_CIPHER */
 873                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_RXCONF */
 874                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_TXCONF */
 875                 0;
 876
 877         return size;
 878 }
 879
 880 void tls_register_device(struct tls_device *device)
 881 {
 882         spin_lock_bh(&device_spinlock);
 883         list_add_tail(&device->dev_list, &device_list);
 884         spin_unlock_bh(&device_spinlock);
 885 }
 886 EXPORT_SYMBOL(tls_register_device);
 887
 888 void tls_unregister_device(struct tls_device *device)
 889 {
 890         spin_lock_bh(&device_spinlock);
 891         list_del(&device->dev_list);
 892         spin_unlock_bh(&device_spinlock);
 893 }
 894 EXPORT_SYMBOL(tls_unregister_device);
 895
 896 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
 897         .name                   = "tls",
 898         .owner                  = THIS_MODULE,
 899         .init                   = tls_init,
 900         .update                 = tls_update,
 901         .get_info               = tls_get_info,
 902         .get_info_size          = tls_get_info_size,
 903 };
 904
 905 static int __init tls_register(void)
 906 {
 907         tls_sw_proto_ops = inet_stream_ops;
 908         tls_sw_proto_ops.splice_read = tls_sw_splice_read;
 909
 910         tls_device_init();
 911         tcp_register_ulp(&tcp_tls_ulp_ops);
 912
 913         return 0;
 914 }
 915
 916 static void __exit tls_unregister(void)
 917 {
 918         tcp_unregister_ulp(&tcp_tls_ulp_ops);
 919         tls_device_cleanup();
 920 }
 921
 922 module_init(tls_register);
 923 module_exit(tls_unregister);