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,
  96                                   !READ_ONCE(sk->sk_write_pending), &wait))
  97                         break;
  98         }
  99         remove_wait_queue(sk_sleep(sk), &wait);
 100         return rc;
 101 }
 102
 103 int tls_push_sg(struct sock *sk,
 104                 struct tls_context *ctx,
 105                 struct scatterlist *sg,
 106                 u16 first_offset,
 107                 int flags)
 108 {
 109         int sendpage_flags = flags | MSG_SENDPAGE_NOTLAST;
 110         int ret = 0;
 111         struct page *p;
 112         size_t size;
 113         int offset = first_offset;
 114
 115         size = sg->length - offset;
 116         offset += sg->offset;
 117
 118         ctx->in_tcp_sendpages = true;
 119         while (1) {
 120                 if (sg_is_last(sg))
 121                         sendpage_flags = flags;
 122
 123                 /* is sending application-limited? */
 124                 tcp_rate_check_app_limited(sk);
 125                 p = sg_page(sg);
 126 retry:
 127                 ret = do_tcp_sendpages(sk, p, offset, size, sendpage_flags);
 128
 129                 if (ret != size) {
 130                         if (ret > 0) {
 131                                 offset += ret;
 132                                 size -= ret;
 133                                 goto retry;
 134                         }
 135
 136                         offset -= sg->offset;
 137                         ctx->partially_sent_offset = offset;
 138                         ctx->partially_sent_record = (void *)sg;
 139                         ctx->in_tcp_sendpages = false;
 140                         return ret;
 141                 }
 142
 143                 put_page(p);
 144                 sk_mem_uncharge(sk, sg->length);
 145                 sg = sg_next(sg);
 146                 if (!sg)
 147                         break;
 148
 149                 offset = sg->offset;
 150                 size = sg->length;
 151         }
 152
 153         ctx->in_tcp_sendpages = false;
 154
 155         return 0;
 156 }
 157
 158 static int tls_handle_open_record(struct sock *sk, int flags)
 159 {
 160         struct tls_context *ctx = tls_get_ctx(sk);
 161
 162         if (tls_is_pending_open_record(ctx))
 163                 return ctx->push_pending_record(sk, flags);
 164
 165         return 0;
 166 }
 167
 168 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
 169                       unsigned char *record_type)
 170 {
 171         struct cmsghdr *cmsg;
 172         int rc = -EINVAL;
 173
 174         for_each_cmsghdr(cmsg, msg) {
 175                 if (!CMSG_OK(msg, cmsg))
 176                         return -EINVAL;
 177                 if (cmsg->cmsg_level != SOL_TLS)
 178                         continue;
 179
 180                 switch (cmsg->cmsg_type) {
 181                 case TLS_SET_RECORD_TYPE:
 182                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(*record_type)))
 183                                 return -EINVAL;
 184
 185                         if (msg->msg_flags & MSG_MORE)
 186                                 return -EINVAL;
 187
 188                         rc = tls_handle_open_record(sk, msg->msg_flags);
 189                         if (rc)
 190                                 return rc;
 191
 192                         *record_type = *(unsigned char *)CMSG_DATA(cmsg);
 193                         rc = 0;
 194                         break;
 195                 default:
 196                         return -EINVAL;
 197                 }
 198         }
 199
 200         return rc;
 201 }
 202
 203 int tls_push_partial_record(struct sock *sk, struct tls_context *ctx,
 204                             int flags)
 205 {
 206         struct scatterlist *sg;
 207         u16 offset;
 208
 209         sg = ctx->partially_sent_record;
 210         offset = ctx->partially_sent_offset;
 211
 212         ctx->partially_sent_record = NULL;
 213         return tls_push_sg(sk, ctx, sg, offset, flags);
 214 }
 215
 216 void tls_free_partial_record(struct sock *sk, struct tls_context *ctx)
 217 {
 218         struct scatterlist *sg;
 219
 220         for (sg = ctx->partially_sent_record; sg; sg = sg_next(sg)) {
 221                 put_page(sg_page(sg));
 222                 sk_mem_uncharge(sk, sg->length);
 223         }
 224         ctx->partially_sent_record = NULL;
 225 }
 226
 227 static void tls_write_space(struct sock *sk)
 228 {
 229         struct tls_context *ctx = tls_get_ctx(sk);
 230
 231         /* If in_tcp_sendpages call lower protocol write space handler
 232          * to ensure we wake up any waiting operations there. For example
 233          * if do_tcp_sendpages where to call sk_wait_event.
 234          */
 235         if (ctx->in_tcp_sendpages) {
 236                 ctx->sk_write_space(sk);
 237                 return;
 238         }
 239
 240 #ifdef CONFIG_TLS_DEVICE
 241         if (ctx->tx_conf == TLS_HW)
 242                 tls_device_write_space(sk, ctx);
 243         else
 244 #endif
 245                 tls_sw_write_space(sk, ctx);
 246
 247         ctx->sk_write_space(sk);
 248 }
 249
 250 /**
 251  * tls_ctx_free() - free TLS ULP context
 252  * @sk:  socket to with @ctx is attached
 253  * @ctx: TLS context structure
 254  *
 255  * Free TLS context. If @sk is %NULL caller guarantees that the socket
 256  * to which @ctx was attached has no outstanding references.
 257  */
 258 void tls_ctx_free(struct sock *sk, struct tls_context *ctx)
 259 {
 260         if (!ctx)
 261                 return;
 262
 263         memzero_explicit(&ctx->crypto_send, sizeof(ctx->crypto_send));
 264         memzero_explicit(&ctx->crypto_recv, sizeof(ctx->crypto_recv));
 265         mutex_destroy(&ctx->tx_lock);
 266
 267         if (sk)
 268                 kfree_rcu(ctx, rcu);
 269         else
 270                 kfree(ctx);
 271 }
 272
 273 static void tls_sk_proto_cleanup(struct sock *sk,
 274                                  struct tls_context *ctx, long timeo)
 275 {
 276         if (unlikely(sk->sk_write_pending) &&
 277             !wait_on_pending_writer(sk, &timeo))
 278                 tls_handle_open_record(sk, 0);
 279
 280         /* We need these for tls_sw_fallback handling of other packets */
 281         if (ctx->tx_conf == TLS_SW) {
 282                 kfree(ctx->tx.rec_seq);
 283                 kfree(ctx->tx.iv);
 284                 tls_sw_release_resources_tx(sk);
 285                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 286         } else if (ctx->tx_conf == TLS_HW) {
 287                 tls_device_free_resources_tx(sk);
 288                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
 289         }
 290
 291         if (ctx->rx_conf == TLS_SW) {
 292                 tls_sw_release_resources_rx(sk);
 293                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
 294         } else if (ctx->rx_conf == TLS_HW) {
 295                 tls_device_offload_cleanup_rx(sk);
 296                 TLS_DEC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
 297         }
 298 }
 299
 300 static void tls_sk_proto_close(struct sock *sk, long timeout)
 301 {
 302         struct inet_connection_sock *icsk = inet_csk(sk);
 303         struct tls_context *ctx = tls_get_ctx(sk);
 304         long timeo = sock_sndtimeo(sk, 0);
 305         bool free_ctx;
 306
 307         if (ctx->tx_conf == TLS_SW)
 308                 tls_sw_cancel_work_tx(ctx);
 309
 310         lock_sock(sk);
 311         free_ctx = ctx->tx_conf != TLS_HW && ctx->rx_conf != TLS_HW;
 312
 313         if (ctx->tx_conf != TLS_BASE || ctx->rx_conf != TLS_BASE)
 314                 tls_sk_proto_cleanup(sk, ctx, timeo);
 315
 316         write_lock_bh(&sk->sk_callback_lock);
 317         if (free_ctx)
 318                 rcu_assign_pointer(icsk->icsk_ulp_data, NULL);
 319         WRITE_ONCE(sk->sk_prot, ctx->sk_proto);
 320         if (sk->sk_write_space == tls_write_space)
 321                 sk->sk_write_space = ctx->sk_write_space;
 322         write_unlock_bh(&sk->sk_callback_lock);
 323         release_sock(sk);
 324         if (ctx->tx_conf == TLS_SW)
 325                 tls_sw_free_ctx_tx(ctx);
 326         if (ctx->rx_conf == TLS_SW || ctx->rx_conf == TLS_HW)
 327                 tls_sw_strparser_done(ctx);
 328         if (ctx->rx_conf == TLS_SW)
 329                 tls_sw_free_ctx_rx(ctx);
 330         ctx->sk_proto->close(sk, timeout);
 331
 332         if (free_ctx)
 333                 tls_ctx_free(sk, ctx);
 334 }
 335
 336 static int do_tls_getsockopt_conf(struct sock *sk, char __user *optval,
 337                                   int __user *optlen, int tx)
 338 {
 339         int rc = 0;
 340         struct tls_context *ctx = tls_get_ctx(sk);
 341         struct tls_crypto_info *crypto_info;
 342         struct cipher_context *cctx;
 343         int len;
 344
 345         if (get_user(len, optlen))
 346                 return -EFAULT;
 347
 348         if (!optval || (len < sizeof(*crypto_info))) {
 349                 rc = -EINVAL;
 350                 goto out;
 351         }
 352
 353         if (!ctx) {
 354                 rc = -EBUSY;
 355                 goto out;
 356         }
 357
 358         /* get user crypto info */
 359         if (tx) {
 360                 crypto_info = &ctx->crypto_send.info;
 361                 cctx = &ctx->tx;
 362         } else {
 363                 crypto_info = &ctx->crypto_recv.info;
 364                 cctx = &ctx->rx;
 365         }
 366
 367         if (!TLS_CRYPTO_INFO_READY(crypto_info)) {
 368                 rc = -EBUSY;
 369                 goto out;
 370         }
 371
 372         if (len == sizeof(*crypto_info)) {
 373                 if (copy_to_user(optval, crypto_info, sizeof(*crypto_info)))
 374                         rc = -EFAULT;
 375                 goto out;
 376         }
 377
 378         switch (crypto_info->cipher_type) {
 379         case TLS_CIPHER_AES_GCM_128: {
 380                 struct tls12_crypto_info_aes_gcm_128 *
 381                   crypto_info_aes_gcm_128 =
 382                   container_of(crypto_info,
 383                                struct tls12_crypto_info_aes_gcm_128,
 384                                info);
 385
 386                 if (len != sizeof(*crypto_info_aes_gcm_128)) {
 387                         rc = -EINVAL;
 388                         goto out;
 389                 }
 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                 if (copy_to_user(optval,
 396                                  crypto_info_aes_gcm_128,
 397                                  sizeof(*crypto_info_aes_gcm_128)))
 398                         rc = -EFAULT;
 399                 break;
 400         }
 401         case TLS_CIPHER_AES_GCM_256: {
 402                 struct tls12_crypto_info_aes_gcm_256 *
 403                   crypto_info_aes_gcm_256 =
 404                   container_of(crypto_info,
 405                                struct tls12_crypto_info_aes_gcm_256,
 406                                info);
 407
 408                 if (len != sizeof(*crypto_info_aes_gcm_256)) {
 409                         rc = -EINVAL;
 410                         goto out;
 411                 }
 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                 if (copy_to_user(optval,
 418                                  crypto_info_aes_gcm_256,
 419                                  sizeof(*crypto_info_aes_gcm_256)))
 420                         rc = -EFAULT;
 421                 break;
 422         }
 423         default:
 424                 rc = -EINVAL;
 425         }
 426
 427 out:
 428         return rc;
 429 }
 430
 431 static int do_tls_getsockopt(struct sock *sk, int optname,
 432                              char __user *optval, int __user *optlen)
 433 {
 434         int rc = 0;
 435
 436         lock_sock(sk);
 437
 438         switch (optname) {
 439         case TLS_TX:
 440         case TLS_RX:
 441                 rc = do_tls_getsockopt_conf(sk, optval, optlen,
 442                                             optname == TLS_TX);
 443                 break;
 444         default:
 445                 rc = -ENOPROTOOPT;
 446                 break;
 447         }
 448
 449         release_sock(sk);
 450
 451         return rc;
 452 }
 453
 454 static int tls_getsockopt(struct sock *sk, int level, int optname,
 455                           char __user *optval, int __user *optlen)
 456 {
 457         struct tls_context *ctx = tls_get_ctx(sk);
 458
 459         if (level != SOL_TLS)
 460                 return ctx->sk_proto->getsockopt(sk, level,
 461                                                  optname, optval, optlen);
 462
 463         return do_tls_getsockopt(sk, optname, optval, optlen);
 464 }
 465
 466 static int do_tls_setsockopt_conf(struct sock *sk, sockptr_t optval,
 467                                   unsigned int optlen, int tx)
 468 {
 469         struct tls_crypto_info *crypto_info;
 470         struct tls_crypto_info *alt_crypto_info;
 471         struct tls_context *ctx = tls_get_ctx(sk);
 472         size_t optsize;
 473         int rc = 0;
 474         int conf;
 475
 476         if (sockptr_is_null(optval) || (optlen < sizeof(*crypto_info))) {
 477                 rc = -EINVAL;
 478                 goto out;
 479         }
 480
 481         if (tx) {
 482                 crypto_info = &ctx->crypto_send.info;
 483                 alt_crypto_info = &ctx->crypto_recv.info;
 484         } else {
 485                 crypto_info = &ctx->crypto_recv.info;
 486                 alt_crypto_info = &ctx->crypto_send.info;
 487         }
 488
 489         /* Currently we don't support set crypto info more than one time */
 490         if (TLS_CRYPTO_INFO_READY(crypto_info)) {
 491                 rc = -EBUSY;
 492                 goto out;
 493         }
 494
 495         rc = copy_from_sockptr(crypto_info, optval, sizeof(*crypto_info));
 496         if (rc) {
 497                 rc = -EFAULT;
 498                 goto err_crypto_info;
 499         }
 500
 501         /* check version */
 502         if (crypto_info->version != TLS_1_2_VERSION &&
 503             crypto_info->version != TLS_1_3_VERSION) {
 504                 rc = -EINVAL;
 505                 goto err_crypto_info;
 506         }
 507
 508         /* Ensure that TLS version and ciphers are same in both directions */
 509         if (TLS_CRYPTO_INFO_READY(alt_crypto_info)) {
 510                 if (alt_crypto_info->version != crypto_info->version ||
 511                     alt_crypto_info->cipher_type != crypto_info->cipher_type) {
 512                         rc = -EINVAL;
 513                         goto err_crypto_info;
 514                 }
 515         }
 516
 517         switch (crypto_info->cipher_type) {
 518         case TLS_CIPHER_AES_GCM_128:
 519                 optsize = sizeof(struct tls12_crypto_info_aes_gcm_128);
 520                 break;
 521         case TLS_CIPHER_AES_GCM_256: {
 522                 optsize = sizeof(struct tls12_crypto_info_aes_gcm_256);
 523                 break;
 524         }
 525         case TLS_CIPHER_AES_CCM_128:
 526                 optsize = sizeof(struct tls12_crypto_info_aes_ccm_128);
 527                 break;
 528         case TLS_CIPHER_CHACHA20_POLY1305:
 529                 optsize = sizeof(struct tls12_crypto_info_chacha20_poly1305);
 530                 break;
 531         default:
 532                 rc = -EINVAL;
 533                 goto err_crypto_info;
 534         }
 535
 536         if (optlen != optsize) {
 537                 rc = -EINVAL;
 538                 goto err_crypto_info;
 539         }
 540
 541         rc = copy_from_sockptr_offset(crypto_info + 1, optval,
 542                                       sizeof(*crypto_info),
 543                                       optlen - sizeof(*crypto_info));
 544         if (rc) {
 545                 rc = -EFAULT;
 546                 goto err_crypto_info;
 547         }
 548
 549         if (tx) {
 550                 rc = tls_set_device_offload(sk, ctx);
 551                 conf = TLS_HW;
 552                 if (!rc) {
 553                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXDEVICE);
 554                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXDEVICE);
 555                 } else {
 556                         rc = tls_set_sw_offload(sk, ctx, 1);
 557                         if (rc)
 558                                 goto err_crypto_info;
 559                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSTXSW);
 560                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRTXSW);
 561                         conf = TLS_SW;
 562                 }
 563         } else {
 564                 rc = tls_set_device_offload_rx(sk, ctx);
 565                 conf = TLS_HW;
 566                 if (!rc) {
 567                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICE);
 568                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXDEVICE);
 569                 } else {
 570                         rc = tls_set_sw_offload(sk, ctx, 0);
 571                         if (rc)
 572                                 goto err_crypto_info;
 573                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXSW);
 574                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSCURRRXSW);
 575                         conf = TLS_SW;
 576                 }
 577                 tls_sw_strparser_arm(sk, ctx);
 578         }
 579
 580         if (tx)
 581                 ctx->tx_conf = conf;
 582         else
 583                 ctx->rx_conf = conf;
 584         update_sk_prot(sk, ctx);
 585         if (tx) {
 586                 ctx->sk_write_space = sk->sk_write_space;
 587                 sk->sk_write_space = tls_write_space;
 588         }
 589         goto out;
 590
 591 err_crypto_info:
 592         memzero_explicit(crypto_info, sizeof(union tls_crypto_context));
 593 out:
 594         return rc;
 595 }
 596
 597 static int do_tls_setsockopt(struct sock *sk, int optname, sockptr_t optval,
 598                              unsigned int optlen)
 599 {
 600         int rc = 0;
 601
 602         switch (optname) {
 603         case TLS_TX:
 604         case TLS_RX:
 605                 lock_sock(sk);
 606                 rc = do_tls_setsockopt_conf(sk, optval, optlen,
 607                                             optname == TLS_TX);
 608                 release_sock(sk);
 609                 break;
 610         default:
 611                 rc = -ENOPROTOOPT;
 612                 break;
 613         }
 614         return rc;
 615 }
 616
 617 static int tls_setsockopt(struct sock *sk, int level, int optname,
 618                           sockptr_t optval, unsigned int optlen)
 619 {
 620         struct tls_context *ctx = tls_get_ctx(sk);
 621
 622         if (level != SOL_TLS)
 623                 return ctx->sk_proto->setsockopt(sk, level, optname, optval,
 624                                                  optlen);
 625
 626         return do_tls_setsockopt(sk, optname, optval, optlen);
 627 }
 628
 629 struct tls_context *tls_ctx_create(struct sock *sk)
 630 {
 631         struct inet_connection_sock *icsk = inet_csk(sk);
 632         struct tls_context *ctx;
 633
 634         ctx = kzalloc(sizeof(*ctx), GFP_ATOMIC);
 635         if (!ctx)
 636                 return NULL;
 637
 638         mutex_init(&ctx->tx_lock);
 639         rcu_assign_pointer(icsk->icsk_ulp_data, ctx);
 640         ctx->sk_proto = READ_ONCE(sk->sk_prot);
 641         ctx->sk = sk;
 642         return ctx;
 643 }
 644
 645 static void build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
 646                             const struct proto_ops *base)
 647 {
 648         ops[TLS_BASE][TLS_BASE] = *base;
 649
 650         ops[TLS_SW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
 651         ops[TLS_SW  ][TLS_BASE].sendpage_locked = tls_sw_sendpage_locked;
 652
 653         ops[TLS_BASE][TLS_SW  ] = ops[TLS_BASE][TLS_BASE];
 654         ops[TLS_BASE][TLS_SW  ].splice_read     = tls_sw_splice_read;
 655
 656         ops[TLS_SW  ][TLS_SW  ] = ops[TLS_SW  ][TLS_BASE];
 657         ops[TLS_SW  ][TLS_SW  ].splice_read     = tls_sw_splice_read;
 658
 659 #ifdef CONFIG_TLS_DEVICE
 660         ops[TLS_HW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
 661         ops[TLS_HW  ][TLS_BASE].sendpage_locked = NULL;
 662
 663         ops[TLS_HW  ][TLS_SW  ] = ops[TLS_BASE][TLS_SW  ];
 664         ops[TLS_HW  ][TLS_SW  ].sendpage_locked = NULL;
 665
 666         ops[TLS_BASE][TLS_HW  ] = ops[TLS_BASE][TLS_SW  ];
 667
 668         ops[TLS_SW  ][TLS_HW  ] = ops[TLS_SW  ][TLS_SW  ];
 669
 670         ops[TLS_HW  ][TLS_HW  ] = ops[TLS_HW  ][TLS_SW  ];
 671         ops[TLS_HW  ][TLS_HW  ].sendpage_locked = NULL;
 672 #endif
 673 #ifdef CONFIG_TLS_TOE
 674         ops[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
 675 #endif
 676 }
 677
 678 static void tls_build_proto(struct sock *sk)
 679 {
 680         int ip_ver = sk->sk_family == AF_INET6 ? TLSV6 : TLSV4;
 681         struct proto *prot = READ_ONCE(sk->sk_prot);
 682
 683         /* Build IPv6 TLS whenever the address of tcpv6 _prot changes */
 684         if (ip_ver == TLSV6 &&
 685             unlikely(prot != smp_load_acquire(&saved_tcpv6_prot))) {
 686                 mutex_lock(&tcpv6_prot_mutex);
 687                 if (likely(prot != saved_tcpv6_prot)) {
 688                         build_protos(tls_prots[TLSV6], prot);
 689                         build_proto_ops(tls_proto_ops[TLSV6],
 690                                         sk->sk_socket->ops);
 691                         smp_store_release(&saved_tcpv6_prot, prot);
 692                 }
 693                 mutex_unlock(&tcpv6_prot_mutex);
 694         }
 695
 696         if (ip_ver == TLSV4 &&
 697             unlikely(prot != smp_load_acquire(&saved_tcpv4_prot))) {
 698                 mutex_lock(&tcpv4_prot_mutex);
 699                 if (likely(prot != saved_tcpv4_prot)) {
 700                         build_protos(tls_prots[TLSV4], prot);
 701                         build_proto_ops(tls_proto_ops[TLSV4],
 702                                         sk->sk_socket->ops);
 703                         smp_store_release(&saved_tcpv4_prot, prot);
 704                 }
 705                 mutex_unlock(&tcpv4_prot_mutex);
 706         }
 707 }
 708
 709 static void build_protos(struct proto prot[TLS_NUM_CONFIG][TLS_NUM_CONFIG],
 710                          const struct proto *base)
 711 {
 712         prot[TLS_BASE][TLS_BASE] = *base;
 713         prot[TLS_BASE][TLS_BASE].setsockopt     = tls_setsockopt;
 714         prot[TLS_BASE][TLS_BASE].getsockopt     = tls_getsockopt;
 715         prot[TLS_BASE][TLS_BASE].close          = tls_sk_proto_close;
 716
 717         prot[TLS_SW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 718         prot[TLS_SW][TLS_BASE].sendmsg          = tls_sw_sendmsg;
 719         prot[TLS_SW][TLS_BASE].sendpage         = tls_sw_sendpage;
 720
 721         prot[TLS_BASE][TLS_SW] = prot[TLS_BASE][TLS_BASE];
 722         prot[TLS_BASE][TLS_SW].recvmsg            = tls_sw_recvmsg;
 723         prot[TLS_BASE][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
 724         prot[TLS_BASE][TLS_SW].close              = tls_sk_proto_close;
 725
 726         prot[TLS_SW][TLS_SW] = prot[TLS_SW][TLS_BASE];
 727         prot[TLS_SW][TLS_SW].recvmsg            = tls_sw_recvmsg;
 728         prot[TLS_SW][TLS_SW].sock_is_readable   = tls_sw_sock_is_readable;
 729         prot[TLS_SW][TLS_SW].close              = tls_sk_proto_close;
 730
 731 #ifdef CONFIG_TLS_DEVICE
 732         prot[TLS_HW][TLS_BASE] = prot[TLS_BASE][TLS_BASE];
 733         prot[TLS_HW][TLS_BASE].sendmsg          = tls_device_sendmsg;
 734         prot[TLS_HW][TLS_BASE].sendpage         = tls_device_sendpage;
 735
 736         prot[TLS_HW][TLS_SW] = prot[TLS_BASE][TLS_SW];
 737         prot[TLS_HW][TLS_SW].sendmsg            = tls_device_sendmsg;
 738         prot[TLS_HW][TLS_SW].sendpage           = tls_device_sendpage;
 739
 740         prot[TLS_BASE][TLS_HW] = prot[TLS_BASE][TLS_SW];
 741
 742         prot[TLS_SW][TLS_HW] = prot[TLS_SW][TLS_SW];
 743
 744         prot[TLS_HW][TLS_HW] = prot[TLS_HW][TLS_SW];
 745 #endif
 746 #ifdef CONFIG_TLS_TOE
 747         prot[TLS_HW_RECORD][TLS_HW_RECORD] = *base;
 748         prot[TLS_HW_RECORD][TLS_HW_RECORD].hash         = tls_toe_hash;
 749         prot[TLS_HW_RECORD][TLS_HW_RECORD].unhash       = tls_toe_unhash;
 750 #endif
 751 }
 752
 753 static int tls_init(struct sock *sk)
 754 {
 755         struct tls_context *ctx;
 756         int rc = 0;
 757
 758         tls_build_proto(sk);
 759
 760 #ifdef CONFIG_TLS_TOE
 761         if (tls_toe_bypass(sk))
 762                 return 0;
 763 #endif
 764
 765         /* The TLS ulp is currently supported only for TCP sockets
 766          * in ESTABLISHED state.
 767          * Supporting sockets in LISTEN state will require us
 768          * to modify the accept implementation to clone rather then
 769          * share the ulp context.
 770          */
 771         if (sk->sk_state != TCP_ESTABLISHED)
 772                 return -ENOTCONN;
 773
 774         /* allocate tls context */
 775         write_lock_bh(&sk->sk_callback_lock);
 776         ctx = tls_ctx_create(sk);
 777         if (!ctx) {
 778                 rc = -ENOMEM;
 779                 goto out;
 780         }
 781
 782         ctx->tx_conf = TLS_BASE;
 783         ctx->rx_conf = TLS_BASE;
 784         update_sk_prot(sk, ctx);
 785 out:
 786         write_unlock_bh(&sk->sk_callback_lock);
 787         return rc;
 788 }
 789
 790 static void tls_update(struct sock *sk, struct proto *p,
 791                        void (*write_space)(struct sock *sk))
 792 {
 793         struct tls_context *ctx;
 794
 795         WARN_ON_ONCE(sk->sk_prot == p);
 796
 797         ctx = tls_get_ctx(sk);
 798         if (likely(ctx)) {
 799                 ctx->sk_write_space = write_space;
 800                 ctx->sk_proto = p;
 801         } else {
 802                 /* Pairs with lockless read in sk_clone_lock(). */
 803                 WRITE_ONCE(sk->sk_prot, p);
 804                 sk->sk_write_space = write_space;
 805         }
 806 }
 807
 808 static int tls_get_info(const struct sock *sk, struct sk_buff *skb)
 809 {
 810         u16 version, cipher_type;
 811         struct tls_context *ctx;
 812         struct nlattr *start;
 813         int err;
 814
 815         start = nla_nest_start_noflag(skb, INET_ULP_INFO_TLS);
 816         if (!start)
 817                 return -EMSGSIZE;
 818
 819         rcu_read_lock();
 820         ctx = rcu_dereference(inet_csk(sk)->icsk_ulp_data);
 821         if (!ctx) {
 822                 err = 0;
 823                 goto nla_failure;
 824         }
 825         version = ctx->prot_info.version;
 826         if (version) {
 827                 err = nla_put_u16(skb, TLS_INFO_VERSION, version);
 828                 if (err)
 829                         goto nla_failure;
 830         }
 831         cipher_type = ctx->prot_info.cipher_type;
 832         if (cipher_type) {
 833                 err = nla_put_u16(skb, TLS_INFO_CIPHER, cipher_type);
 834                 if (err)
 835                         goto nla_failure;
 836         }
 837         err = nla_put_u16(skb, TLS_INFO_TXCONF, tls_user_config(ctx, true));
 838         if (err)
 839                 goto nla_failure;
 840
 841         err = nla_put_u16(skb, TLS_INFO_RXCONF, tls_user_config(ctx, false));
 842         if (err)
 843                 goto nla_failure;
 844
 845         rcu_read_unlock();
 846         nla_nest_end(skb, start);
 847         return 0;
 848
 849 nla_failure:
 850         rcu_read_unlock();
 851         nla_nest_cancel(skb, start);
 852         return err;
 853 }
 854
 855 static size_t tls_get_info_size(const struct sock *sk)
 856 {
 857         size_t size = 0;
 858
 859         size += nla_total_size(0) +             /* INET_ULP_INFO_TLS */
 860                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_VERSION */
 861                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_CIPHER */
 862                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_RXCONF */
 863                 nla_total_size(sizeof(u16)) +   /* TLS_INFO_TXCONF */
 864                 0;
 865
 866         return size;
 867 }
 868
 869 static int __net_init tls_init_net(struct net *net)
 870 {
 871         int err;
 872
 873         net->mib.tls_statistics = alloc_percpu(struct linux_tls_mib);
 874         if (!net->mib.tls_statistics)
 875                 return -ENOMEM;
 876
 877         err = tls_proc_init(net);
 878         if (err)
 879                 goto err_free_stats;
 880
 881         return 0;
 882 err_free_stats:
 883         free_percpu(net->mib.tls_statistics);
 884         return err;
 885 }
 886
 887 static void __net_exit tls_exit_net(struct net *net)
 888 {
 889         tls_proc_fini(net);
 890         free_percpu(net->mib.tls_statistics);
 891 }
 892
 893 static struct pernet_operations tls_proc_ops = {
 894         .init = tls_init_net,
 895         .exit = tls_exit_net,
 896 };
 897
 898 static struct tcp_ulp_ops tcp_tls_ulp_ops __read_mostly = {
 899         .name                   = "tls",
 900         .owner                  = THIS_MODULE,
 901         .init                   = tls_init,
 902         .update                 = tls_update,
 903         .get_info               = tls_get_info,
 904         .get_info_size          = tls_get_info_size,
 905 };
 906
 907 static int __init tls_register(void)
 908 {
 909         int err;
 910
 911         err = register_pernet_subsys(&tls_proc_ops);
 912         if (err)
 913                 return err;
 914
 915         err = tls_device_init();
 916         if (err) {
 917                 unregister_pernet_subsys(&tls_proc_ops);
 918                 return err;
 919         }
 920
 921         tcp_register_ulp(&tcp_tls_ulp_ops);
 922
 923         return 0;
 924 }
 925
 926 static void __exit tls_unregister(void)
 927 {
 928         tcp_unregister_ulp(&tcp_tls_ulp_ops);
 929         tls_device_cleanup();
 930         unregister_pernet_subsys(&tls_proc_ops);
 931 }
 932
 933 module_init(tls_register);
 934 module_exit(tls_unregister);