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_proto_ops[TLS_NUM_PROTS][TLS_NUM_CONFIG][TLS_NUM_CONFIG];
  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         WRITE_ONCE(sk->sk_socket->ops,
  75                    &tls_proto_ops[ip_ver][ctx->tx_conf][ctx->rx_conf]);
  76 }
  77
  78 int wait_on_pending_writer(struct sock *sk, long *timeo)
  79 {
  80         int rc = 0;
  81         DEFINE_WAIT_FUNC(wait, woken_wake_function);
  82
  83         add_wait_queue(sk_sleep(sk), &wait);
  84         while (1) {
  85                 if (!*timeo) {
  86                         rc = -EAGAIN;
  87                         break;
  88                 }
  89
  90                 if (signal_pending(current)) {
  91                         rc = sock_intr_errno(*timeo);
  92                         break;
  93                 }
  94
  95                 if (sk_wait_event(sk, timeo, !sk->sk_write_pending, &wait))
  96                         break;
  97         }
  98         remove_wait_queue(sk_sleep(sk), &wait);
  99         return rc;
 100 }
 101
 102 int tls_push_sg(struct sock *sk,
 103                 struct tls_context *ctx,
 104                 struct scatterlist *sg,
 105                 u16 first_offset,
 106                 int flags)
 107 {
 108         int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
 109         int ret = 0;
 110         struct page *p;
 111         size_t size;
 112         int offset = first_offset;
 113
 114         size = sg->length - offset;
 115         offset += sg->offset;
 116
 117         ctx->in_tcp_sendpages = true;
 118         while (1) {
 119                 if (sg_is_last(sg))
 120                         sendpage_flags = flags;
 121
 122                 /* is sending application-limited? */
 123                 tcp_rate_check_app_limited(sk);
 124                 p = sg_page(sg);
 125 retry:
 126                 ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
 127
 128                 if (ret != size) {
 129                         if (ret > 0) {
 130                                 offset += ret;
 131                                 size -= ret;
 132                                 goto retry;
 133                         }
 134
 135                         offset -= sg->offset;
 136                         ctx->partially_sent_offset = offset;
 137                         ctx->partially_sent_record = (void *)sg;
 138                         ctx->in_tcp_sendpages = false;
 139                         return ret;
 140                 }
 141
 142                 put_page(p);
 143                 sk_mem_uncharge(sk, sg->length);
 144                 sg = sg_next(sg);
 145                 if (!sg)
 146                         break;
 147
 148                 offset = sg->offset;
 149                 size = sg->length;
 150         }
 151
 152         ctx->in_tcp_sendpages = false;
 153
 154         return 0;
 155 }
 156
 157 static int tls_handle_open_record(struct sock *sk, int flags)
 158 {
 159         struct tls_context *ctx = tls_get_ctx(sk);
 160
 161         if (tls_is_pending_open_record(ctx))
 162                 return ctx->push_pending_record(sk, flags);
 163
 164         return 0;
 165 }
 166
 167 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
 168                       unsigned char *record_type)
 169 {
 170         struct cmsghdr *cmsg;
 171         int rc = -EINVAL;
 172
 173         for_each_cmsghdr(cmsg, msg) {
 174                 if (!CMSG_OK(msg, cmsg))
 175                         return -EINVAL;
 176                 if (cmsg->cmsg_level != SOL_TLS)
 177                         continue;
 178
 179                 switch (cmsg->cmsg_type) {
 180                 case TLS_SET_RECORD_TYPE:
 181                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
 182                                 return -EINVAL;
 183
 184                         if (msg->msg_flags & MSG_MORE)
 185                                 return -EINVAL;
 186
 187                         rc = tls_handle_open_record(sk, msg->msg_flags);
 188                         if (rc)
 189                                 return rc;
 190
 191                         *record_type = *(unsigned char *)CMSG_DATA(cmsg);
 192                         rc = 0;
 193                         break;
 194                 default:
 195                         return -EINVAL;
 196                 }
 197         }
 198
 199         return rc;
 200 }
 201
 202 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
 203                             int flags)
 204 {
 205         struct scatterlist *sg;
 206         u16 offset;
 207
 208         sg = ctx->partially_sent_record;
 209         offset = ctx->partially_sent_offset;
 210
 211         ctx->partially_sent_record = NULL;
 212         return tls_push_sg(sk, ctx, sg, offset, flags);
 213 }
 214
 215 void tls_free_partial_record(struct sock *sk, struct tls_context *ctx)
 216 {
 217         struct scatterlist *sg;
 218
 219         for (sg = ctx->partially_sent_record; sg; sg = sg_next(sg)) {
 220                 put_page(sg_page(sg));
 221                 sk_mem_uncharge(sk, sg->length);
 222         }
 223         ctx->partially_sent_record = NULL;
 224 }
 225
 226 static void tls_write_space(struct sock *sk)
 227 {
 228         struct tls_context *ctx = tls_get_ctx(sk);
 229
 230         /* If in_tcp_sendpages call lower protocol write space handler
 231          * to ensure we wake up any waiting operations there. For example
 232          * if do_tcp_sendpages where to call sk_wait_event.
 233          */
 234         if (ctx->in_tcp_sendpages) {
 235                 ctx->sk_write_space(sk);
 236                 return;
 237         }
 238
 239 #ifdef CONFIG_TLS_DEVICE
 240         if (ctx->tx_conf == TLS_HW)
 241                 tls_device_write_space(sk, ctx);
 242         else
 243 #endif
 244                 tls_sw_write_space(sk, ctx);
 245
 246         ctx->sk_write_space(sk);
 247 }
 248
 249 /**
 250  * tls_ctx_free() - free TLS ULP context
 251  * @sk:  socket to with @ctx is attached
 252  * @ctx: TLS context structure
 253  *
 254  * Free TLS context. If @sk is %NULL caller guarantees that the socket
 255  * to which @ctx was attached has no outstanding references.
 256  */
 257 void tls_ctx_free(struct sock *sk, struct tls_context *ctx)
 258 {
 259         if (!ctx)
 260                 return;
 261
 262         memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
 263         memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
 264         mutex_destroy(&ctx->tx_lock);
 265
 266         if (sk)
 267                 kfree_rcu(ctx, rcu);
 268         else
 269                 kfree(ctx);
 270 }
 271
 272 static void tls_sk_proto_cleanup(struct sock *sk,
 273                                  struct tls_context *ctx, long timeo)
 274 {
 275         if (unlikely(sk->sk_write_pending) &&
 276             !wait_on_pending_writer(sk, &timeo))
 277                 tls_handle_open_record(sk, 0);
 278
 279         /* We need these for tls_sw_fallback handling of other packets */
 280         if (ctx->tx_conf == TLS_SW) {
 281                 kfree(ctx->tx.rec_seq);
 282                 kfree(ctx->tx.iv);
 283                 tls_sw_release_resources_tx(sk);
 284                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 285         } else if (ctx->tx_conf == TLS_HW) {
 286                 tls_device_free_resources_tx(sk);
 287                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
 288         }
 289
 290         if (ctx->rx_conf == TLS_SW) {
 291                 tls_sw_release_resources_rx(sk);
 292                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
 293         } else if (ctx->rx_conf == TLS_HW) {
 294                 tls_device_offload_cleanup_rx(sk);
 295                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
 296         }
 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         WRITE_ONCE(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_conf(struct sock *sk, char __user *optval,
 336                                   int __user *optlen, int tx)
 337 {
 338         int rc = 0;
 339         struct tls_context *ctx = tls_get_ctx(sk);
 340         struct tls_crypto_info *crypto_info;
 341         struct cipher_context *cctx;
 342         int len;
 343
 344         if (get_user(len, optlen))
 345                 return -EFAULT;
 346
 347         if (!optval || (len < sizeof(*crypto_info))) {
 348                 rc = -EINVAL;
 349                 goto out;
 350         }
 351
 352         if (!ctx) {
 353                 rc = -EBUSY;
 354                 goto out;
 355         }
 356
 357         /* get user crypto info */
 358         if (tx) {
 359                 crypto_info = &ctx->crypto_send.info;
 360                 cctx = &ctx->tx;
 361         } else {
 362                 crypto_info = &ctx->crypto_recv.info;
 363                 cctx = &ctx->rx;
 364         }
 365
 366         if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
 367                 rc = -EBUSY;
 368                 goto out;
 369         }
 370
 371         if (len == sizeof(*crypto_info)) {
 372                 if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
 373                         rc = -EFAULT;
 374                 goto out;
 375         }
 376
 377         switch (crypto_info->cipher_type) {
 378         case TLS_CIPHER_AES_GCM_128: {
 379                 struct tls12_crypto_info_aes_gcm_128 *
 380                   crypto_info_aes_gcm_128 =
 381                   container_of(crypto_info,
 382                                struct tls12_crypto_info_aes_gcm_128,
 383                                info);
 384
 385                 if (len != sizeof(*crypto_info_aes_gcm_128)) {
 386                         rc = -EINVAL;
 387                         goto out;
 388                 }
 389                 lock_sock(sk);
 390                 memcpy(crypto_info_aes_gcm_128->iv,
 391                        cctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
 392                        TLS_CIPHER_AES_GCM_128_IV_SIZE);
 393                 memcpy(crypto_info_aes_gcm_128->rec_seq, cctx->rec_seq,
 394                        TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
 395                 release_sock(sk);
 396                 if (copy_to_user(optval,
 397                                  crypto_info_aes_gcm_128,
 398                                  sizeof(*crypto_info_aes_gcm_128)))
 399                         rc = -EFAULT;
 400                 break;
 401         }
 402         case TLS_CIPHER_AES_GCM_256: {
 403                 struct tls12_crypto_info_aes_gcm_256 *
 404                   crypto_info_aes_gcm_256 =
 405                   container_of(crypto_info,
 406                                struct tls12_crypto_info_aes_gcm_256,
 407                                info);
 408
 409                 if (len != sizeof(*crypto_info_aes_gcm_256)) {
 410                         rc = -EINVAL;
 411                         goto out;
 412                 }
 413                 lock_sock(sk);
 414                 memcpy(crypto_info_aes_gcm_256->iv,
 415                        cctx->iv + TLS_CIPHER_AES_GCM_256_SALT_SIZE,
 416                        TLS_CIPHER_AES_GCM_256_IV_SIZE);
 417                 memcpy(crypto_info_aes_gcm_256->rec_seq, cctx->rec_seq,
 418                        TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
 419                 release_sock(sk);
 420                 if (copy_to_user(optval,
 421                                  crypto_info_aes_gcm_256,
 422                                  sizeof(*crypto_info_aes_gcm_256)))
 423                         rc = -EFAULT;
 424                 break;
 425         }
 426         default:
 427                 rc = -EINVAL;
 428         }
 429
 430 out:
 431         return rc;
 432 }
 433
 434 static int do_tls_getsockopt(struct sock *sk, int optname,
 435                              char __user *optval, int __user *optlen)
 436 {
 437         int rc = 0;
 438
 439         switch (optname) {
 440         case TLS_TX:
 441         case TLS_RX:
 442                 rc = do_tls_getsockopt_conf(sk, optval, optlen,
 443                                             optname == TLS_TX);
 444                 break;
 445         default:
 446                 rc = -ENOPROTOOPT;
 447                 break;
 448         }
 449         return rc;
 450 }
 451
 452 static int tls_getsockopt(struct sock *sk, int level, int optname,
 453                           char __user *optval, int __user *optlen)
 454 {
 455         struct tls_context *ctx = tls_get_ctx(sk);
 456
 457         if (level != SOL_TLS)
 458                 return ctx->sk_proto->getsockopt(sk, level,
 459                                                  optname, optval, optlen);
 460
 461         return do_tls_getsockopt(sk, optname, optval, optlen);
 462 }
 463
 464 static int do_tls_setsockopt_conf(struct sock *sk, sockptr_t optval,
 465                                   unsigned int optlen, int tx)
 466 {
 467         struct tls_crypto_info *crypto_info;
 468         struct tls_crypto_info *alt_crypto_info;
 469         struct tls_context *ctx = tls_get_ctx(sk);
 470         size_t optsize;
 471         int rc = 0;
 472         int conf;
 473
 474         if (sockptr_is_null(optval) || (optlen < sizeof(*crypto_info))) {
 475                 rc = -EINVAL;
 476                 goto out;
 477         }
 478
 479         if (tx) {
 480                 crypto_info = &ctx->crypto_send.info;
 481                 alt_crypto_info = &ctx->crypto_recv.info;
 482         } else {
 483                 crypto_info = &ctx->crypto_recv.info;
 484                 alt_crypto_info = &ctx->crypto_send.info;
 485         }
 486
 487         /* Currently we don't support set crypto info more than one time */
 488         if (TLS_CRYPTO_INFO_READY(crypto_info)) {
 489                 rc = -EBUSY;
 490                 goto out;
 491         }
 492
 493         rc = copy_from_sockptr(crypto_info, optval, sizeof(*crypto_info));
 494         if (rc) {
 495                 rc = -EFAULT;
 496                 goto err_crypto_info;
 497         }
 498
 499         /* check version */
 500         if (crypto_info->version != TLS_1_2_VERSION &&
 501             crypto_info->version != TLS_1_3_VERSION) {
 502                 rc = -EINVAL;
 503                 goto err_crypto_info;
 504         }
 505
 506         /* Ensure that TLS version and ciphers are same in both directions */
 507         if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
 508                 if (alt_crypto_info->version != crypto_info->version ||
 509                     alt_crypto_info->cipher_type != crypto_info->cipher_type) {
 510                         rc = -EINVAL;
 511                         goto err_crypto_info;
 512                 }
 513         }
 514
 515         switch (crypto_info->cipher_type) {
 516         case TLS_CIPHER_AES_GCM_128:
 517                 optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
 518                 break;
 519         case TLS_CIPHER_AES_GCM_256: {
 520                 optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
 521                 break;
 522         }
 523         case TLS_CIPHER_AES_CCM_128:
 524                 optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
 525                 break;
 526         case TLS_CIPHER_CHACHA20_POLY1305:
 527                 optsize = sizeof(struct tls12_crypto_info_chacha20_poly1305);
 528                 break;
 529         default:
 530                 rc = -EINVAL;
 531                 goto err_crypto_info;
 532         }
 533
 534         if (optlen != optsize) {
 535                 rc = -EINVAL;
 536                 goto err_crypto_info;
 537         }
 538
 539         rc = copy_from_sockptr_offset(crypto_info + 1, optval,
 540                                       sizeof(*crypto_info),
 541                                       optlen - sizeof(*crypto_info));
 542         if (rc) {
 543                 rc = -EFAULT;
 544                 goto err_crypto_info;
 545         }
 546
 547         if (tx) {
 548                 rc = tls_set_device_offload(sk, ctx);
 549                 conf = TLS_HW;
 550                 if (!rc) {
 551                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
 552                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
 553                 } else {
 554                         rc = tls_set_sw_offload(sk, ctx, 1);
 555                         if (rc)
 556                                 goto err_crypto_info;
 557                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
 558                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 559                         conf = TLS_SW;
 560                 }
 561         } else {
 562                 rc = tls_set_device_offload_rx(sk, ctx);
 563                 conf = TLS_HW;
 564                 if (!rc) {
 565                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
 566                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
 567                 } else {
 568                         rc = tls_set_sw_offload(sk, ctx, 0);
 569                         if (rc)
 570                                 goto err_crypto_info;
 571                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
 572                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
 573                         conf = TLS_SW;
 574                 }
 575                 tls_sw_strparser_arm(sk, ctx);
 576         }
 577
 578         if (tx)
 579                 ctx->tx_conf = conf;
 580         else
 581                 ctx->rx_conf = conf;
 582         update_sk_prot(sk, ctx);
 583         if (tx) {
 584                 ctx->sk_write_space = sk->sk_write_space;
 585                 sk->sk_write_space = tls_write_space;
 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         ctx->sk = sk;
 640         return ctx;
 641 }
 642
 643 static void build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
 644                             const struct proto_ops *base)
 645 {
 646         ops[TLS_BASE][TLS_BASE] = *base;
 647
 648         ops[TLS_SW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
 649         ops[TLS_SW  ][TLS_BASE].sendpage_locked = tls_sw_sendpage_locked;
 650
 651         ops[TLS_BASE][TLS_SW  ] = ops[TLS_BASE][TLS_BASE];
 652         ops[TLS_BASE][TLS_SW  ].splice_read     = tls_sw_splice_read;
 653
 654         ops[TLS_SW  ][TLS_SW  ] = ops[TLS_SW  ][TLS_BASE];
 655         ops[TLS_SW  ][TLS_SW  ].splice_read     = tls_sw_splice_read;
 656
 657 #ifdef CONFIG_TLS_DEVICE
 658         ops[TLS_HW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
 659         ops[TLS_HW  ][TLS_BASE].sendpage_locked = NULL;
 660
 661         ops[TLS_HW  ][TLS_SW  ] = ops[TLS_BASE][TLS_SW  ];
 662         ops[TLS_HW  ][TLS_SW  ].sendpage_locked = NULL;
 663
 664         ops[TLS_BASE][TLS_HW  ] = ops[TLS_BASE][TLS_SW  ];
 665
 666         ops[TLS_SW  ][TLS_HW  ] = ops[TLS_SW  ][TLS_SW  ];
 667
 668         ops[TLS_HW  ][TLS_HW  ] = ops[TLS_HW  ][TLS_SW  ];
 669         ops[TLS_HW  ][TLS_HW  ].sendpage_locked = NULL;
 670 #endif
 671 #ifdef CONFIG_TLS_TOE
 672         ops[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
 673 #endif
 674 }
 675
 676 static void tls_build_proto(struct sock *sk)
 677 {
 678         int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
 679         struct proto *prot = READ_ONCE(sk->sk_prot);
 680
 681         /* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
 682         if (ip_ver == TLSV6 &&
 683             unlikely(prot != smp_load_acquire(&saved_tcpv6_prot))) {
 684                 mutex_lock(&tcpv6_prot_mutex);
 685                 if (likely(prot != saved_tcpv6_prot)) {
 686                         build_protos(tls_prots[TLSV6], prot);
 687                         build_proto_ops(tls_proto_ops[TLSV6],
 688                                         sk->sk_socket->ops);
 689                         smp_store_release(&saved_tcpv6_prot, prot);
 690                 }
 691                 mutex_unlock(&tcpv6_prot_mutex);
 692         }
 693
 694         if (ip_ver == TLSV4 &&
 695             unlikely(prot != smp_load_acquire(&saved_tcpv4_prot))) {
 696                 mutex_lock(&tcpv4_prot_mutex);
 697                 if (likely(prot != saved_tcpv4_prot)) {
 698                         build_protos(tls_prots[TLSV4], prot);
 699                         build_proto_ops(tls_proto_ops[TLSV4],
 700                                         sk->sk_socket->ops);
 701                         smp_store_release(&saved_tcpv4_prot, prot);
 702                 }
 703                 mutex_unlock(&tcpv4_prot_mutex);
 704         }
 705 }
 706
 707 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
 708                          const struct proto *base)
 709 {
 710         prot[TLS_BASE][TLS_BASE] = *base;
 711         prot[TLS_BASE][TLS_BASE].setsockopt     = tls_setsockopt;
 712         prot[TLS_BASE][TLS_BASE].getsockopt     = tls_getsockopt;
 713         prot[TLS_BASE][TLS_BASE].close          = tls_sk_proto_close;
 714
 715         prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 716         prot[TLS_SW][TLS_BASE].sendmsg          = tls_sw_sendmsg;
 717         prot[TLS_SW][TLS_BASE].sendpage         = tls_sw_sendpage;
 718
 719         prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
 720         prot[TLS_BASE][TLS_SW].recvmsg            = tls_sw_recvmsg;
 721         prot[TLS_BASE][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
 722         prot[TLS_BASE][TLS_SW].close              = tls_sk_proto_close;
 723
 724         prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
 725         prot[TLS_SW][TLS_SW].recvmsg            = tls_sw_recvmsg;
 726         prot[TLS_SW][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
 727         prot[TLS_SW][TLS_SW].close              = tls_sk_proto_close;
 728
 729 #ifdef CONFIG_TLS_DEVICE
 730         prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 731         prot[TLS_HW][TLS_BASE].sendmsg          = tls_device_sendmsg;
 732         prot[TLS_HW][TLS_BASE].sendpage         = tls_device_sendpage;
 733
 734         prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
 735         prot[TLS_HW][TLS_SW].sendmsg            = tls_device_sendmsg;
 736         prot[TLS_HW][TLS_SW].sendpage           = tls_device_sendpage;
 737
 738         prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
 739
 740         prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
 741
 742         prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
 743 #endif
 744 #ifdef CONFIG_TLS_TOE
 745         prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
 746         prot[TLS_HW_RECORD][TLS_HW_RECORD].hash         = tls_toe_hash;
 747         prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash       = tls_toe_unhash;
 748 #endif
 749 }
 750
 751 static int tls_init(struct sock *sk)
 752 {
 753         struct tls_context *ctx;
 754         int rc = 0;
 755
 756         tls_build_proto(sk);
 757
 758 #ifdef CONFIG_TLS_TOE
 759         if (tls_toe_bypass(sk))
 760                 return 0;
 761 #endif
 762
 763         /* The TLS ulp is currently supported only for TCP sockets
 764          * in ESTABLISHED state.
 765          * Supporting sockets in LISTEN state will require us
 766          * to modify the accept implementation to clone rather then
 767          * share the ulp context.
 768          */
 769         if (sk->sk_state != TCP_ESTABLISHED)
 770                 return -ENOTCONN;
 771
 772         /* allocate tls context */
 773         write_lock_bh(&sk->sk_callback_lock);
 774         ctx = tls_ctx_create(sk);
 775         if (!ctx) {
 776                 rc = -ENOMEM;
 777                 goto out;
 778         }
 779
 780         ctx->tx_conf = TLS_BASE;
 781         ctx->rx_conf = TLS_BASE;
 782         update_sk_prot(sk, ctx);
 783 out:
 784         write_unlock_bh(&sk->sk_callback_lock);
 785         return rc;
 786 }
 787
 788 static void tls_update(struct sock *sk, struct proto *p,
 789                        void (*write_space)(struct sock *sk))
 790 {
 791         struct tls_context *ctx;
 792
 793         WARN_ON_ONCE(sk->sk_prot == p);
 794
 795         ctx = tls_get_ctx(sk);
 796         if (likely(ctx)) {
 797                 ctx->sk_write_space = write_space;
 798                 ctx->sk_proto = p;
 799         } else {
 800                 /* Pairs with lockless read in sk_clone_lock(). */
 801                 WRITE_ONCE(sk->sk_prot, p);
 802                 sk->sk_write_space = write_space;
 803         }
 804 }
 805
 806 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
 807 {
 808         u16 version, cipher_type;
 809         struct tls_context *ctx;
 810         struct nlattr *start;
 811         int err;
 812
 813         start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
 814         if (!start)
 815                 return -EMSGSIZE;
 816
 817         rcu_read_lock();
 818         ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
 819         if (!ctx) {
 820                 err = 0;
 821                 goto nla_failure;
 822         }
 823         version = ctx->prot_info.version;
 824         if (version) {
 825                 err = nla_put_u16(skb, TLS_INFO_VERSION, version);
 826                 if (err)
 827                         goto nla_failure;
 828         }
 829         cipher_type = ctx->prot_info.cipher_type;
 830         if (cipher_type) {
 831                 err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
 832                 if (err)
 833                         goto nla_failure;
 834         }
 835         err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
 836         if (err)
 837                 goto nla_failure;
 838
 839         err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
 840         if (err)
 841                 goto nla_failure;
 842
 843         rcu_read_unlock();
 844         nla_nest_end(skb, start);
 845         return 0;
 846
 847 nla_failure:
 848         rcu_read_unlock();
 849         nla_nest_cancel(skb, start);
 850         return err;
 851 }
 852
 853 static size_t tls_get_info_size(const struct sock *sk)
 854 {
 855         size_t size = 0;
 856
 857         size += nla_total_size(0) +             /* INET_ULP_INFO_TLS */
 858                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_VERSION */
 859                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_CIPHER */
 860                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_RXCONF */
 861                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_TXCONF */
 862                 0;
 863
 864         return size;
 865 }
 866
 867 static int __net_init tls_init_net(struct net *net)
 868 {
 869         int err;
 870
 871         net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
 872         if (!net->mib.tls_statistics)
 873                 return -ENOMEM;
 874
 875         err = tls_proc_init(net);
 876         if (err)
 877                 goto err_free_stats;
 878
 879         return 0;
 880 err_free_stats:
 881         free_percpu(net->mib.tls_statistics);
 882         return err;
 883 }
 884
 885 static void __net_exit tls_exit_net(struct net *net)
 886 {
 887         tls_proc_fini(net);
 888         free_percpu(net->mib.tls_statistics);
 889 }
 890
 891 static struct pernet_operations tls_proc_ops = {
 892         .init = tls_init_net,
 893         .exit = tls_exit_net,
 894 };
 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         int err;
 908
 909         err = register_pernet_subsys(&tls_proc_ops);
 910         if (err)
 911                 return err;
 912
 913         err = tls_device_init();
 914         if (err) {
 915                 unregister_pernet_subsys(&tls_proc_ops);
 916                 return err;
 917         }
 918
 919         tcp_register_ulp(&tcp_tls_ulp_ops);
 920
 921         return 0;
 922 }
 923
 924 static void __exit tls_unregister(void)
 925 {
 926         tcp_unregister_ulp(&tcp_tls_ulp_ops);
 927         tls_device_cleanup();
 928         unregister_pernet_subsys(&tls_proc_ops);
 929 }
 930
 931 module_init(tls_register);
 932 module_exit(tls_unregister);