net/tls/tls_sw.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  * Copyright (c) 2016-2017, Lance Chao <lancerchao@fb.com>. All rights reserved.
   5  * Copyright (c) 2016, Fridolin Pokorny <fridolin.pokorny@gmail.com>. All rights reserved.
   6  * Copyright (c) 2016, Nikos Mavrogiannopoulos <nmav@gnutls.org>. All rights reserved.
   7  * Copyright (c) 2018, Covalent IO, Inc. http://covalent.io
   8  *
   9  * This software is available to you under a choice of one of two
  10  * licenses.  You may choose to be licensed under the terms of the GNU
  11  * General Public License (GPL) Version 2, available from the file
  12  * COPYING in the main directory of this source tree, or the
  13  * OpenIB.org BSD license below:
  14  *
  15  *     Redistribution and use in source and binary forms, with or
  16  *     without modification, are permitted provided that the following
  17  *     conditions are met:
  18  *
  19  *      - Redistributions of source code must retain the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer.
  22  *
  23  *      - Redistributions in binary form must reproduce the above
  24  *        copyright notice, this list of conditions and the following
  25  *        disclaimer in the documentation and/or other materials
  26  *        provided with the distribution.
  27  *
  28  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  29  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  30  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  31  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  32  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  33  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  34  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  35  * SOFTWARE.
  36  */
  37
  38 #include <linux/bug.h>
  39 #include <linux/sched/signal.h>
  40 #include <linux/module.h>
  41 #include <linux/kernel.h>
  42 #include <linux/splice.h>
  43 #include <crypto/aead.h>
  44
  45 #include <net/strparser.h>
  46 #include <net/tls.h>
  47 #include <trace/events/sock.h>
  48
  49 #include "tls.h"
  50
  51 struct tls_decrypt_arg {
  52         struct_group(inargs,
  53         bool zc;
  54         bool async;
  55         bool async_done;
  56         u8 tail;
  57         );
  58
  59         struct sk_buff *skb;
  60 };
  61
  62 struct tls_decrypt_ctx {
  63         struct sock *sk;
  64         u8 iv[TLS_MAX_IV_SIZE];
  65         u8 aad[TLS_MAX_AAD_SIZE];
  66         u8 tail;
  67         bool free_sgout;
  68         struct scatterlist sg[];
  69 };
  70
  71 noinline void tls_err_abort(struct sock *sk, int err)
  72 {
  73         WARN_ON_ONCE(err >= 0);
  74         /* sk->sk_err should contain a positive error code. */
  75         WRITE_ONCE(sk->sk_err, -err);
  76         /* Paired with smp_rmb() in tcp_poll() */
  77         smp_wmb();
  78         sk_error_report(sk);
  79 }
  80
  81 static int __skb_nsg(struct sk_buff *skb, int offset, int len,
  82                      unsigned int recursion_level)
  83 {
  84         int start = skb_headlen(skb);
  85         int i, chunk = start - offset;
  86         struct sk_buff *frag_iter;
  87         int elt = 0;
  88
  89         if (unlikely(recursion_level >= 24))
  90                 return -EMSGSIZE;
  91
  92         if (chunk > 0) {
  93                 if (chunk > len)
  94                         chunk = len;
  95                 elt++;
  96                 len -= chunk;
  97                 if (len == 0)
  98                         return elt;
  99                 offset += chunk;
 100         }
 101
 102         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 103                 int end;
 104
 105                 WARN_ON(start > offset + len);
 106
 107                 end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]);
 108                 chunk = end - offset;
 109                 if (chunk > 0) {
 110                         if (chunk > len)
 111                                 chunk = len;
 112                         elt++;
 113                         len -= chunk;
 114                         if (len == 0)
 115                                 return elt;
 116                         offset += chunk;
 117                 }
 118                 start = end;
 119         }
 120
 121         if (unlikely(skb_has_frag_list(skb))) {
 122                 skb_walk_frags(skb, frag_iter) {
 123                         int end, ret;
 124
 125                         WARN_ON(start > offset + len);
 126
 127                         end = start + frag_iter->len;
 128                         chunk = end - offset;
 129                         if (chunk > 0) {
 130                                 if (chunk > len)
 131                                         chunk = len;
 132                                 ret = __skb_nsg(frag_iter, offset - start, chunk,
 133                                                 recursion_level + 1);
 134                                 if (unlikely(ret < 0))
 135                                         return ret;
 136                                 elt += ret;
 137                                 len -= chunk;
 138                                 if (len == 0)
 139                                         return elt;
 140                                 offset += chunk;
 141                         }
 142                         start = end;
 143                 }
 144         }
 145         BUG_ON(len);
 146         return elt;
 147 }
 148
 149 /* Return the number of scatterlist elements required to completely map the
 150  * skb, or -EMSGSIZE if the recursion depth is exceeded.
 151  */
 152 static int skb_nsg(struct sk_buff *skb, int offset, int len)
 153 {
 154         return __skb_nsg(skb, offset, len, 0);
 155 }
 156
 157 static int tls_padding_length(struct tls_prot_info *prot, struct sk_buff *skb,
 158                               struct tls_decrypt_arg *darg)
 159 {
 160         struct strp_msg *rxm = strp_msg(skb);
 161         struct tls_msg *tlm = tls_msg(skb);
 162         int sub = 0;
 163
 164         /* Determine zero-padding length */
 165         if (prot->version == TLS_1_3_VERSION) {
 166                 int offset = rxm->full_len - TLS_TAG_SIZE - 1;
 167                 char content_type = darg->zc ? darg->tail : 0;
 168                 int err;
 169
 170                 while (content_type == 0) {
 171                         if (offset < prot->prepend_size)
 172                                 return -EBADMSG;
 173                         err = skb_copy_bits(skb, rxm->offset + offset,
 174                                             &content_type, 1);
 175                         if (err)
 176                                 return err;
 177                         if (content_type)
 178                                 break;
 179                         sub++;
 180                         offset--;
 181                 }
 182                 tlm->control = content_type;
 183         }
 184         return sub;
 185 }
 186
 187 static void tls_decrypt_done(void *data, int err)
 188 {
 189         struct aead_request *aead_req = data;
 190         struct crypto_aead *aead = crypto_aead_reqtfm(aead_req);
 191         struct scatterlist *sgout = aead_req->dst;
 192         struct tls_sw_context_rx *ctx;
 193         struct tls_decrypt_ctx *dctx;
 194         struct tls_context *tls_ctx;
 195         struct scatterlist *sg;
 196         unsigned int pages;
 197         struct sock *sk;
 198         int aead_size;
 199
 200         /* If requests get too backlogged crypto API returns -EBUSY and calls
 201          * ->complete(-EINPROGRESS) immediately followed by ->complete(0)
 202          * to make waiting for backlog to flush with crypto_wait_req() easier.
 203          * First wait converts -EBUSY -> -EINPROGRESS, and the second one
 204          * -EINPROGRESS -> 0.
 205          * We have a single struct crypto_async_request per direction, this
 206          * scheme doesn't help us, so just ignore the first ->complete().
 207          */
 208         if (err == -EINPROGRESS)
 209                 return;
 210
 211         aead_size = sizeof(*aead_req) + crypto_aead_reqsize(aead);
 212         aead_size = ALIGN(aead_size, __alignof__(*dctx));
 213         dctx = (void *)((u8 *)aead_req + aead_size);
 214
 215         sk = dctx->sk;
 216         tls_ctx = tls_get_ctx(sk);
 217         ctx = tls_sw_ctx_rx(tls_ctx);
 218
 219         /* Propagate if there was an err */
 220         if (err) {
 221                 if (err == -EBADMSG)
 222                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
 223                 ctx->async_wait.err = err;
 224                 tls_err_abort(sk, err);
 225         }
 226
 227         /* Free the destination pages if skb was not decrypted inplace */
 228         if (dctx->free_sgout) {
 229                 /* Skip the first S/G entry as it points to AAD */
 230                 for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) {
 231                         if (!sg)
 232                                 break;
 233                         put_page(sg_page(sg));
 234                 }
 235         }
 236
 237         kfree(aead_req);
 238
 239         if (atomic_dec_and_test(&ctx->decrypt_pending))
 240                 complete(&ctx->async_wait.completion);
 241 }
 242
 243 static int tls_decrypt_async_wait(struct tls_sw_context_rx *ctx)
 244 {
 245         if (!atomic_dec_and_test(&ctx->decrypt_pending))
 246                 crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
 247         atomic_inc(&ctx->decrypt_pending);
 248
 249         return ctx->async_wait.err;
 250 }
 251
 252 static int tls_do_decryption(struct sock *sk,
 253                              struct scatterlist *sgin,
 254                              struct scatterlist *sgout,
 255                              char *iv_recv,
 256                              size_t data_len,
 257                              struct aead_request *aead_req,
 258                              struct tls_decrypt_arg *darg)
 259 {
 260         struct tls_context *tls_ctx = tls_get_ctx(sk);
 261         struct tls_prot_info *prot = &tls_ctx->prot_info;
 262         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
 263         int ret;
 264
 265         aead_request_set_tfm(aead_req, ctx->aead_recv);
 266         aead_request_set_ad(aead_req, prot->aad_size);
 267         aead_request_set_crypt(aead_req, sgin, sgout,
 268                                data_len + prot->tag_size,
 269                                (u8 *)iv_recv);
 270
 271         if (darg->async) {
 272                 aead_request_set_callback(aead_req,
 273                                           CRYPTO_TFM_REQ_MAY_BACKLOG,
 274                                           tls_decrypt_done, aead_req);
 275                 DEBUG_NET_WARN_ON_ONCE(atomic_read(&ctx->decrypt_pending) < 1);
 276                 atomic_inc(&ctx->decrypt_pending);
 277         } else {
 278                 DECLARE_CRYPTO_WAIT(wait);
 279
 280                 aead_request_set_callback(aead_req,
 281                                           CRYPTO_TFM_REQ_MAY_BACKLOG,
 282                                           crypto_req_done, &wait);
 283                 ret = crypto_aead_decrypt(aead_req);
 284                 if (ret == -EINPROGRESS || ret == -EBUSY)
 285                         ret = crypto_wait_req(ret, &wait);
 286                 return ret;
 287         }
 288
 289         ret = crypto_aead_decrypt(aead_req);
 290         if (ret == -EINPROGRESS)
 291                 return 0;
 292
 293         if (ret == -EBUSY) {
 294                 ret = tls_decrypt_async_wait(ctx);
 295                 darg->async_done = true;
 296                 /* all completions have run, we're not doing async anymore */
 297                 darg->async = false;
 298                 return ret;
 299         }
 300
 301         atomic_dec(&ctx->decrypt_pending);
 302         darg->async = false;
 303
 304         return ret;
 305 }
 306
 307 static void tls_trim_both_msgs(struct sock *sk, int target_size)
 308 {
 309         struct tls_context *tls_ctx = tls_get_ctx(sk);
 310         struct tls_prot_info *prot = &tls_ctx->prot_info;
 311         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 312         struct tls_rec *rec = ctx->open_rec;
 313
 314         sk_msg_trim(sk, &rec->msg_plaintext, target_size);
 315         if (target_size > 0)
 316                 target_size += prot->overhead_size;
 317         sk_msg_trim(sk, &rec->msg_encrypted, target_size);
 318 }
 319
 320 static int tls_alloc_encrypted_msg(struct sock *sk, int len)
 321 {
 322         struct tls_context *tls_ctx = tls_get_ctx(sk);
 323         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 324         struct tls_rec *rec = ctx->open_rec;
 325         struct sk_msg *msg_en = &rec->msg_encrypted;
 326
 327         return sk_msg_alloc(sk, msg_en, len, 0);
 328 }
 329
 330 static int tls_clone_plaintext_msg(struct sock *sk, int required)
 331 {
 332         struct tls_context *tls_ctx = tls_get_ctx(sk);
 333         struct tls_prot_info *prot = &tls_ctx->prot_info;
 334         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 335         struct tls_rec *rec = ctx->open_rec;
 336         struct sk_msg *msg_pl = &rec->msg_plaintext;
 337         struct sk_msg *msg_en = &rec->msg_encrypted;
 338         int skip, len;
 339
 340         /* We add page references worth len bytes from encrypted sg
 341          * at the end of plaintext sg. It is guaranteed that msg_en
 342          * has enough required room (ensured by caller).
 343          */
 344         len = required - msg_pl->sg.size;
 345
 346         /* Skip initial bytes in msg_en's data to be able to use
 347          * same offset of both plain and encrypted data.
 348          */
 349         skip = prot->prepend_size + msg_pl->sg.size;
 350
 351         return sk_msg_clone(sk, msg_pl, msg_en, skip, len);
 352 }
 353
 354 static struct tls_rec *tls_get_rec(struct sock *sk)
 355 {
 356         struct tls_context *tls_ctx = tls_get_ctx(sk);
 357         struct tls_prot_info *prot = &tls_ctx->prot_info;
 358         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 359         struct sk_msg *msg_pl, *msg_en;
 360         struct tls_rec *rec;
 361         int mem_size;
 362
 363         mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send);
 364
 365         rec = kzalloc(mem_size, sk->sk_allocation);
 366         if (!rec)
 367                 return NULL;
 368
 369         msg_pl = &rec->msg_plaintext;
 370         msg_en = &rec->msg_encrypted;
 371
 372         sk_msg_init(msg_pl);
 373         sk_msg_init(msg_en);
 374
 375         sg_init_table(rec->sg_aead_in, 2);
 376         sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size);
 377         sg_unmark_end(&rec->sg_aead_in[1]);
 378
 379         sg_init_table(rec->sg_aead_out, 2);
 380         sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size);
 381         sg_unmark_end(&rec->sg_aead_out[1]);
 382
 383         rec->sk = sk;
 384
 385         return rec;
 386 }
 387
 388 static void tls_free_rec(struct sock *sk, struct tls_rec *rec)
 389 {
 390         sk_msg_free(sk, &rec->msg_encrypted);
 391         sk_msg_free(sk, &rec->msg_plaintext);
 392         kfree(rec);
 393 }
 394
 395 static void tls_free_open_rec(struct sock *sk)
 396 {
 397         struct tls_context *tls_ctx = tls_get_ctx(sk);
 398         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 399         struct tls_rec *rec = ctx->open_rec;
 400
 401         if (rec) {
 402                 tls_free_rec(sk, rec);
 403                 ctx->open_rec = NULL;
 404         }
 405 }
 406
 407 int tls_tx_records(struct sock *sk, int flags)
 408 {
 409         struct tls_context *tls_ctx = tls_get_ctx(sk);
 410         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 411         struct tls_rec *rec, *tmp;
 412         struct sk_msg *msg_en;
 413         int tx_flags, rc = 0;
 414
 415         if (tls_is_partially_sent_record(tls_ctx)) {
 416                 rec = list_first_entry(&ctx->tx_list,
 417                                        struct tls_rec, list);
 418
 419                 if (flags == -1)
 420                         tx_flags = rec->tx_flags;
 421                 else
 422                         tx_flags = flags;
 423
 424                 rc = tls_push_partial_record(sk, tls_ctx, tx_flags);
 425                 if (rc)
 426                         goto tx_err;
 427
 428                 /* Full record has been transmitted.
 429                  * Remove the head of tx_list
 430                  */
 431                 list_del(&rec->list);
 432                 sk_msg_free(sk, &rec->msg_plaintext);
 433                 kfree(rec);
 434         }
 435
 436         /* Tx all ready records */
 437         list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
 438                 if (READ_ONCE(rec->tx_ready)) {
 439                         if (flags == -1)
 440                                 tx_flags = rec->tx_flags;
 441                         else
 442                                 tx_flags = flags;
 443
 444                         msg_en = &rec->msg_encrypted;
 445                         rc = tls_push_sg(sk, tls_ctx,
 446                                          &msg_en->sg.data[msg_en->sg.curr],
 447                                          0, tx_flags);
 448                         if (rc)
 449                                 goto tx_err;
 450
 451                         list_del(&rec->list);
 452                         sk_msg_free(sk, &rec->msg_plaintext);
 453                         kfree(rec);
 454                 } else {
 455                         break;
 456                 }
 457         }
 458
 459 tx_err:
 460         if (rc < 0 && rc != -EAGAIN)
 461                 tls_err_abort(sk, -EBADMSG);
 462
 463         return rc;
 464 }
 465
 466 static void tls_encrypt_done(void *data, int err)
 467 {
 468         struct tls_sw_context_tx *ctx;
 469         struct tls_context *tls_ctx;
 470         struct tls_prot_info *prot;
 471         struct tls_rec *rec = data;
 472         struct scatterlist *sge;
 473         struct sk_msg *msg_en;
 474         struct sock *sk;
 475
 476         if (err == -EINPROGRESS) /* see the comment in tls_decrypt_done() */
 477                 return;
 478
 479         msg_en = &rec->msg_encrypted;
 480
 481         sk = rec->sk;
 482         tls_ctx = tls_get_ctx(sk);
 483         prot = &tls_ctx->prot_info;
 484         ctx = tls_sw_ctx_tx(tls_ctx);
 485
 486         sge = sk_msg_elem(msg_en, msg_en->sg.curr);
 487         sge->offset -= prot->prepend_size;
 488         sge->length += prot->prepend_size;
 489
 490         /* Check if error is previously set on socket */
 491         if (err || sk->sk_err) {
 492                 rec = NULL;
 493
 494                 /* If err is already set on socket, return the same code */
 495                 if (sk->sk_err) {
 496                         ctx->async_wait.err = -sk->sk_err;
 497                 } else {
 498                         ctx->async_wait.err = err;
 499                         tls_err_abort(sk, err);
 500                 }
 501         }
 502
 503         if (rec) {
 504                 struct tls_rec *first_rec;
 505
 506                 /* Mark the record as ready for transmission */
 507                 smp_store_mb(rec->tx_ready, true);
 508
 509                 /* If received record is at head of tx_list, schedule tx */
 510                 first_rec = list_first_entry(&ctx->tx_list,
 511                                              struct tls_rec, list);
 512                 if (rec == first_rec) {
 513                         /* Schedule the transmission */
 514                         if (!test_and_set_bit(BIT_TX_SCHEDULED,
 515                                               &ctx->tx_bitmask))
 516                                 schedule_delayed_work(&ctx->tx_work.work, 1);
 517                 }
 518         }
 519
 520         if (atomic_dec_and_test(&ctx->encrypt_pending))
 521                 complete(&ctx->async_wait.completion);
 522 }
 523
 524 static int tls_encrypt_async_wait(struct tls_sw_context_tx *ctx)
 525 {
 526         if (!atomic_dec_and_test(&ctx->encrypt_pending))
 527                 crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
 528         atomic_inc(&ctx->encrypt_pending);
 529
 530         return ctx->async_wait.err;
 531 }
 532
 533 static int tls_do_encryption(struct sock *sk,
 534                              struct tls_context *tls_ctx,
 535                              struct tls_sw_context_tx *ctx,
 536                              struct aead_request *aead_req,
 537                              size_t data_len, u32 start)
 538 {
 539         struct tls_prot_info *prot = &tls_ctx->prot_info;
 540         struct tls_rec *rec = ctx->open_rec;
 541         struct sk_msg *msg_en = &rec->msg_encrypted;
 542         struct scatterlist *sge = sk_msg_elem(msg_en, start);
 543         int rc, iv_offset = 0;
 544
 545         /* For CCM based ciphers, first byte of IV is a constant */
 546         switch (prot->cipher_type) {
 547         case TLS_CIPHER_AES_CCM_128:
 548                 rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE;
 549                 iv_offset = 1;
 550                 break;
 551         case TLS_CIPHER_SM4_CCM:
 552                 rec->iv_data[0] = TLS_SM4_CCM_IV_B0_BYTE;
 553                 iv_offset = 1;
 554                 break;
 555         }
 556
 557         memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv,
 558                prot->iv_size + prot->salt_size);
 559
 560         tls_xor_iv_with_seq(prot, rec->iv_data + iv_offset,
 561                             tls_ctx->tx.rec_seq);
 562
 563         sge->offset += prot->prepend_size;
 564         sge->length -= prot->prepend_size;
 565
 566         msg_en->sg.curr = start;
 567
 568         aead_request_set_tfm(aead_req, ctx->aead_send);
 569         aead_request_set_ad(aead_req, prot->aad_size);
 570         aead_request_set_crypt(aead_req, rec->sg_aead_in,
 571                                rec->sg_aead_out,
 572                                data_len, rec->iv_data);
 573
 574         aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
 575                                   tls_encrypt_done, rec);
 576
 577         /* Add the record in tx_list */
 578         list_add_tail((struct list_head *)&rec->list, &ctx->tx_list);
 579         DEBUG_NET_WARN_ON_ONCE(atomic_read(&ctx->encrypt_pending) < 1);
 580         atomic_inc(&ctx->encrypt_pending);
 581
 582         rc = crypto_aead_encrypt(aead_req);
 583         if (rc == -EBUSY) {
 584                 rc = tls_encrypt_async_wait(ctx);
 585                 rc = rc ?: -EINPROGRESS;
 586         }
 587         if (!rc || rc != -EINPROGRESS) {
 588                 atomic_dec(&ctx->encrypt_pending);
 589                 sge->offset -= prot->prepend_size;
 590                 sge->length += prot->prepend_size;
 591         }
 592
 593         if (!rc) {
 594                 WRITE_ONCE(rec->tx_ready, true);
 595         } else if (rc != -EINPROGRESS) {
 596                 list_del(&rec->list);
 597                 return rc;
 598         }
 599
 600         /* Unhook the record from context if encryption is not failure */
 601         ctx->open_rec = NULL;
 602         tls_advance_record_sn(sk, prot, &tls_ctx->tx);
 603         return rc;
 604 }
 605
 606 static int tls_split_open_record(struct sock *sk, struct tls_rec *from,
 607                                  struct tls_rec **to, struct sk_msg *msg_opl,
 608                                  struct sk_msg *msg_oen, u32 split_point,
 609                                  u32 tx_overhead_size, u32 *orig_end)
 610 {
 611         u32 i, j, bytes = 0, apply = msg_opl->apply_bytes;
 612         struct scatterlist *sge, *osge, *nsge;
 613         u32 orig_size = msg_opl->sg.size;
 614         struct scatterlist tmp = { };
 615         struct sk_msg *msg_npl;
 616         struct tls_rec *new;
 617         int ret;
 618
 619         new = tls_get_rec(sk);
 620         if (!new)
 621                 return -ENOMEM;
 622         ret = sk_msg_alloc(sk, &new->msg_encrypted, msg_opl->sg.size +
 623                            tx_overhead_size, 0);
 624         if (ret < 0) {
 625                 tls_free_rec(sk, new);
 626                 return ret;
 627         }
 628
 629         *orig_end = msg_opl->sg.end;
 630         i = msg_opl->sg.start;
 631         sge = sk_msg_elem(msg_opl, i);
 632         while (apply && sge->length) {
 633                 if (sge->length > apply) {
 634                         u32 len = sge->length - apply;
 635
 636                         get_page(sg_page(sge));
 637                         sg_set_page(&tmp, sg_page(sge), len,
 638                                     sge->offset + apply);
 639                         sge->length = apply;
 640                         bytes += apply;
 641                         apply = 0;
 642                 } else {
 643                         apply -= sge->length;
 644                         bytes += sge->length;
 645                 }
 646
 647                 sk_msg_iter_var_next(i);
 648                 if (i == msg_opl->sg.end)
 649                         break;
 650                 sge = sk_msg_elem(msg_opl, i);
 651         }
 652
 653         msg_opl->sg.end = i;
 654         msg_opl->sg.curr = i;
 655         msg_opl->sg.copybreak = 0;
 656         msg_opl->apply_bytes = 0;
 657         msg_opl->sg.size = bytes;
 658
 659         msg_npl = &new->msg_plaintext;
 660         msg_npl->apply_bytes = apply;
 661         msg_npl->sg.size = orig_size - bytes;
 662
 663         j = msg_npl->sg.start;
 664         nsge = sk_msg_elem(msg_npl, j);
 665         if (tmp.length) {
 666                 memcpy(nsge, &tmp, sizeof(*nsge));
 667                 sk_msg_iter_var_next(j);
 668                 nsge = sk_msg_elem(msg_npl, j);
 669         }
 670
 671         osge = sk_msg_elem(msg_opl, i);
 672         while (osge->length) {
 673                 memcpy(nsge, osge, sizeof(*nsge));
 674                 sg_unmark_end(nsge);
 675                 sk_msg_iter_var_next(i);
 676                 sk_msg_iter_var_next(j);
 677                 if (i == *orig_end)
 678                         break;
 679                 osge = sk_msg_elem(msg_opl, i);
 680                 nsge = sk_msg_elem(msg_npl, j);
 681         }
 682
 683         msg_npl->sg.end = j;
 684         msg_npl->sg.curr = j;
 685         msg_npl->sg.copybreak = 0;
 686
 687         *to = new;
 688         return 0;
 689 }
 690
 691 static void tls_merge_open_record(struct sock *sk, struct tls_rec *to,
 692                                   struct tls_rec *from, u32 orig_end)
 693 {
 694         struct sk_msg *msg_npl = &from->msg_plaintext;
 695         struct sk_msg *msg_opl = &to->msg_plaintext;
 696         struct scatterlist *osge, *nsge;
 697         u32 i, j;
 698
 699         i = msg_opl->sg.end;
 700         sk_msg_iter_var_prev(i);
 701         j = msg_npl->sg.start;
 702
 703         osge = sk_msg_elem(msg_opl, i);
 704         nsge = sk_msg_elem(msg_npl, j);
 705
 706         if (sg_page(osge) == sg_page(nsge) &&
 707             osge->offset + osge->length == nsge->offset) {
 708                 osge->length += nsge->length;
 709                 put_page(sg_page(nsge));
 710         }
 711
 712         msg_opl->sg.end = orig_end;
 713         msg_opl->sg.curr = orig_end;
 714         msg_opl->sg.copybreak = 0;
 715         msg_opl->apply_bytes = msg_opl->sg.size + msg_npl->sg.size;
 716         msg_opl->sg.size += msg_npl->sg.size;
 717
 718         sk_msg_free(sk, &to->msg_encrypted);
 719         sk_msg_xfer_full(&to->msg_encrypted, &from->msg_encrypted);
 720
 721         kfree(from);
 722 }
 723
 724 static int tls_push_record(struct sock *sk, int flags,
 725                            unsigned char record_type)
 726 {
 727         struct tls_context *tls_ctx = tls_get_ctx(sk);
 728         struct tls_prot_info *prot = &tls_ctx->prot_info;
 729         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 730         struct tls_rec *rec = ctx->open_rec, *tmp = NULL;
 731         u32 i, split_point, orig_end;
 732         struct sk_msg *msg_pl, *msg_en;
 733         struct aead_request *req;
 734         bool split;
 735         int rc;
 736
 737         if (!rec)
 738                 return 0;
 739
 740         msg_pl = &rec->msg_plaintext;
 741         msg_en = &rec->msg_encrypted;
 742
 743         split_point = msg_pl->apply_bytes;
 744         split = split_point && split_point < msg_pl->sg.size;
 745         if (unlikely((!split &&
 746                       msg_pl->sg.size +
 747                       prot->overhead_size > msg_en->sg.size) ||
 748                      (split &&
 749                       split_point +
 750                       prot->overhead_size > msg_en->sg.size))) {
 751                 split = true;
 752                 split_point = msg_en->sg.size;
 753         }
 754         if (split) {
 755                 rc = tls_split_open_record(sk, rec, &tmp, msg_pl, msg_en,
 756                                            split_point, prot->overhead_size,
 757                                            &orig_end);
 758                 if (rc < 0)
 759                         return rc;
 760                 /* This can happen if above tls_split_open_record allocates
 761                  * a single large encryption buffer instead of two smaller
 762                  * ones. In this case adjust pointers and continue without
 763                  * split.
 764                  */
 765                 if (!msg_pl->sg.size) {
 766                         tls_merge_open_record(sk, rec, tmp, orig_end);
 767                         msg_pl = &rec->msg_plaintext;
 768                         msg_en = &rec->msg_encrypted;
 769                         split = false;
 770                 }
 771                 sk_msg_trim(sk, msg_en, msg_pl->sg.size +
 772                             prot->overhead_size);
 773         }
 774
 775         rec->tx_flags = flags;
 776         req = &rec->aead_req;
 777
 778         i = msg_pl->sg.end;
 779         sk_msg_iter_var_prev(i);
 780
 781         rec->content_type = record_type;
 782         if (prot->version == TLS_1_3_VERSION) {
 783                 /* Add content type to end of message.  No padding added */
 784                 sg_set_buf(&rec->sg_content_type, &rec->content_type, 1);
 785                 sg_mark_end(&rec->sg_content_type);
 786                 sg_chain(msg_pl->sg.data, msg_pl->sg.end + 1,
 787                          &rec->sg_content_type);
 788         } else {
 789                 sg_mark_end(sk_msg_elem(msg_pl, i));
 790         }
 791
 792         if (msg_pl->sg.end < msg_pl->sg.start) {
 793                 sg_chain(&msg_pl->sg.data[msg_pl->sg.start],
 794                          MAX_SKB_FRAGS - msg_pl->sg.start + 1,
 795                          msg_pl->sg.data);
 796         }
 797
 798         i = msg_pl->sg.start;
 799         sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]);
 800
 801         i = msg_en->sg.end;
 802         sk_msg_iter_var_prev(i);
 803         sg_mark_end(sk_msg_elem(msg_en, i));
 804
 805         i = msg_en->sg.start;
 806         sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]);
 807
 808         tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size,
 809                      tls_ctx->tx.rec_seq, record_type, prot);
 810
 811         tls_fill_prepend(tls_ctx,
 812                          page_address(sg_page(&msg_en->sg.data[i])) +
 813                          msg_en->sg.data[i].offset,
 814                          msg_pl->sg.size + prot->tail_size,
 815                          record_type);
 816
 817         tls_ctx->pending_open_record_frags = false;
 818
 819         rc = tls_do_encryption(sk, tls_ctx, ctx, req,
 820                                msg_pl->sg.size + prot->tail_size, i);
 821         if (rc < 0) {
 822                 if (rc != -EINPROGRESS) {
 823                         tls_err_abort(sk, -EBADMSG);
 824                         if (split) {
 825                                 tls_ctx->pending_open_record_frags = true;
 826                                 tls_merge_open_record(sk, rec, tmp, orig_end);
 827                         }
 828                 }
 829                 ctx->async_capable = 1;
 830                 return rc;
 831         } else if (split) {
 832                 msg_pl = &tmp->msg_plaintext;
 833                 msg_en = &tmp->msg_encrypted;
 834                 sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size);
 835                 tls_ctx->pending_open_record_frags = true;
 836                 ctx->open_rec = tmp;
 837         }
 838
 839         return tls_tx_records(sk, flags);
 840 }
 841
 842 static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk,
 843                                bool full_record, u8 record_type,
 844                                ssize_t *copied, int flags)
 845 {
 846         struct tls_context *tls_ctx = tls_get_ctx(sk);
 847         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 848         struct sk_msg msg_redir = { };
 849         struct sk_psock *psock;
 850         struct sock *sk_redir;
 851         struct tls_rec *rec;
 852         bool enospc, policy, redir_ingress;
 853         int err = 0, send;
 854         u32 delta = 0;
 855
 856         policy = !(flags & MSG_SENDPAGE_NOPOLICY);
 857         psock = sk_psock_get(sk);
 858         if (!psock || !policy) {
 859                 err = tls_push_record(sk, flags, record_type);
 860                 if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) {
 861                         *copied -= sk_msg_free(sk, msg);
 862                         tls_free_open_rec(sk);
 863                         err = -sk->sk_err;
 864                 }
 865                 if (psock)
 866                         sk_psock_put(sk, psock);
 867                 return err;
 868         }
 869 more_data:
 870         enospc = sk_msg_full(msg);
 871         if (psock->eval == __SK_NONE) {
 872                 delta = msg->sg.size;
 873                 psock->eval = sk_psock_msg_verdict(sk, psock, msg);
 874                 delta -= msg->sg.size;
 875         }
 876         if (msg->cork_bytes && msg->cork_bytes > msg->sg.size &&
 877             !enospc && !full_record) {
 878                 err = -ENOSPC;
 879                 goto out_err;
 880         }
 881         msg->cork_bytes = 0;
 882         send = msg->sg.size;
 883         if (msg->apply_bytes && msg->apply_bytes < send)
 884                 send = msg->apply_bytes;
 885
 886         switch (psock->eval) {
 887         case __SK_PASS:
 888                 err = tls_push_record(sk, flags, record_type);
 889                 if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) {
 890                         *copied -= sk_msg_free(sk, msg);
 891                         tls_free_open_rec(sk);
 892                         err = -sk->sk_err;
 893                         goto out_err;
 894                 }
 895                 break;
 896         case __SK_REDIRECT:
 897                 redir_ingress = psock->redir_ingress;
 898                 sk_redir = psock->sk_redir;
 899                 memcpy(&msg_redir, msg, sizeof(*msg));
 900                 if (msg->apply_bytes < send)
 901                         msg->apply_bytes = 0;
 902                 else
 903                         msg->apply_bytes -= send;
 904                 sk_msg_return_zero(sk, msg, send);
 905                 msg->sg.size -= send;
 906                 release_sock(sk);
 907                 err = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress,
 908                                             &msg_redir, send, flags);
 909                 lock_sock(sk);
 910                 if (err < 0) {
 911                         *copied -= sk_msg_free_nocharge(sk, &msg_redir);
 912                         msg->sg.size = 0;
 913                 }
 914                 if (msg->sg.size == 0)
 915                         tls_free_open_rec(sk);
 916                 break;
 917         case __SK_DROP:
 918         default:
 919                 sk_msg_free_partial(sk, msg, send);
 920                 if (msg->apply_bytes < send)
 921                         msg->apply_bytes = 0;
 922                 else
 923                         msg->apply_bytes -= send;
 924                 if (msg->sg.size == 0)
 925                         tls_free_open_rec(sk);
 926                 *copied -= (send + delta);
 927                 err = -EACCES;
 928         }
 929
 930         if (likely(!err)) {
 931                 bool reset_eval = !ctx->open_rec;
 932
 933                 rec = ctx->open_rec;
 934                 if (rec) {
 935                         msg = &rec->msg_plaintext;
 936                         if (!msg->apply_bytes)
 937                                 reset_eval = true;
 938                 }
 939                 if (reset_eval) {
 940                         psock->eval = __SK_NONE;
 941                         if (psock->sk_redir) {
 942                                 sock_put(psock->sk_redir);
 943                                 psock->sk_redir = NULL;
 944                         }
 945                 }
 946                 if (rec)
 947                         goto more_data;
 948         }
 949  out_err:
 950         sk_psock_put(sk, psock);
 951         return err;
 952 }
 953
 954 static int tls_sw_push_pending_record(struct sock *sk, int flags)
 955 {
 956         struct tls_context *tls_ctx = tls_get_ctx(sk);
 957         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
 958         struct tls_rec *rec = ctx->open_rec;
 959         struct sk_msg *msg_pl;
 960         size_t copied;
 961
 962         if (!rec)
 963                 return 0;
 964
 965         msg_pl = &rec->msg_plaintext;
 966         copied = msg_pl->sg.size;
 967         if (!copied)
 968                 return 0;
 969
 970         return bpf_exec_tx_verdict(msg_pl, sk, true, TLS_RECORD_TYPE_DATA,
 971                                    &copied, flags);
 972 }
 973
 974 static int tls_sw_sendmsg_splice(struct sock *sk, struct msghdr *msg,
 975                                  struct sk_msg *msg_pl, size_t try_to_copy,
 976                                  ssize_t *copied)
 977 {
 978         struct page *page = NULL, **pages = &page;
 979
 980         do {
 981                 ssize_t part;
 982                 size_t off;
 983
 984                 part = iov_iter_extract_pages(&msg->msg_iter, &pages,
 985                                               try_to_copy, 1, 0, &off);
 986                 if (part <= 0)
 987                         return part ?: -EIO;
 988
 989                 if (WARN_ON_ONCE(!sendpage_ok(page))) {
 990                         iov_iter_revert(&msg->msg_iter, part);
 991                         return -EIO;
 992                 }
 993
 994                 sk_msg_page_add(msg_pl, page, part, off);
 995                 msg_pl->sg.copybreak = 0;
 996                 msg_pl->sg.curr = msg_pl->sg.end;
 997                 sk_mem_charge(sk, part);
 998                 *copied += part;
 999                 try_to_copy -= part;
1000         } while (try_to_copy && !sk_msg_full(msg_pl));
1001
1002         return 0;
1003 }
1004
1005 static int tls_sw_sendmsg_locked(struct sock *sk, struct msghdr *msg,
1006                                  size_t size)
1007 {
1008         long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1009         struct tls_context *tls_ctx = tls_get_ctx(sk);
1010         struct tls_prot_info *prot = &tls_ctx->prot_info;
1011         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1012         bool async_capable = ctx->async_capable;
1013         unsigned char record_type = TLS_RECORD_TYPE_DATA;
1014         bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1015         bool eor = !(msg->msg_flags & MSG_MORE);
1016         size_t try_to_copy;
1017         ssize_t copied = 0;
1018         struct sk_msg *msg_pl, *msg_en;
1019         struct tls_rec *rec;
1020         int required_size;
1021         int num_async = 0;
1022         bool full_record;
1023         int record_room;
1024         int num_zc = 0;
1025         int orig_size;
1026         int ret = 0;
1027
1028         if (!eor && (msg->msg_flags & MSG_EOR))
1029                 return -EINVAL;
1030
1031         if (unlikely(msg->msg_controllen)) {
1032                 ret = tls_process_cmsg(sk, msg, &record_type);
1033                 if (ret) {
1034                         if (ret == -EINPROGRESS)
1035                                 num_async++;
1036                         else if (ret != -EAGAIN)
1037                                 goto send_end;
1038                 }
1039         }
1040
1041         while (msg_data_left(msg)) {
1042                 if (sk->sk_err) {
1043                         ret = -sk->sk_err;
1044                         goto send_end;
1045                 }
1046
1047                 if (ctx->open_rec)
1048                         rec = ctx->open_rec;
1049                 else
1050                         rec = ctx->open_rec = tls_get_rec(sk);
1051                 if (!rec) {
1052                         ret = -ENOMEM;
1053                         goto send_end;
1054                 }
1055
1056                 msg_pl = &rec->msg_plaintext;
1057                 msg_en = &rec->msg_encrypted;
1058
1059                 orig_size = msg_pl->sg.size;
1060                 full_record = false;
1061                 try_to_copy = msg_data_left(msg);
1062                 record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size;
1063                 if (try_to_copy >= record_room) {
1064                         try_to_copy = record_room;
1065                         full_record = true;
1066                 }
1067
1068                 required_size = msg_pl->sg.size + try_to_copy +
1069                                 prot->overhead_size;
1070
1071                 if (!sk_stream_memory_free(sk))
1072                         goto wait_for_sndbuf;
1073
1074 alloc_encrypted:
1075                 ret = tls_alloc_encrypted_msg(sk, required_size);
1076                 if (ret) {
1077                         if (ret != -ENOSPC)
1078                                 goto wait_for_memory;
1079
1080                         /* Adjust try_to_copy according to the amount that was
1081                          * actually allocated. The difference is due
1082                          * to max sg elements limit
1083                          */
1084                         try_to_copy -= required_size - msg_en->sg.size;
1085                         full_record = true;
1086                 }
1087
1088                 if (try_to_copy && (msg->msg_flags & MSG_SPLICE_PAGES)) {
1089                         ret = tls_sw_sendmsg_splice(sk, msg, msg_pl,
1090                                                     try_to_copy, &copied);
1091                         if (ret < 0)
1092                                 goto send_end;
1093                         tls_ctx->pending_open_record_frags = true;
1094
1095                         if (sk_msg_full(msg_pl))
1096                                 full_record = true;
1097
1098                         if (full_record || eor)
1099                                 goto copied;
1100                         continue;
1101                 }
1102
1103                 if (!is_kvec && (full_record || eor) && !async_capable) {
1104                         u32 first = msg_pl->sg.end;
1105
1106                         ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter,
1107                                                         msg_pl, try_to_copy);
1108                         if (ret)
1109                                 goto fallback_to_reg_send;
1110
1111                         num_zc++;
1112                         copied += try_to_copy;
1113
1114                         sk_msg_sg_copy_set(msg_pl, first);
1115                         ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1116                                                   record_type, &copied,
1117                                                   msg->msg_flags);
1118                         if (ret) {
1119                                 if (ret == -EINPROGRESS)
1120                                         num_async++;
1121                                 else if (ret == -ENOMEM)
1122                                         goto wait_for_memory;
1123                                 else if (ctx->open_rec && ret == -ENOSPC)
1124                                         goto rollback_iter;
1125                                 else if (ret != -EAGAIN)
1126                                         goto send_end;
1127                         }
1128                         continue;
1129 rollback_iter:
1130                         copied -= try_to_copy;
1131                         sk_msg_sg_copy_clear(msg_pl, first);
1132                         iov_iter_revert(&msg->msg_iter,
1133                                         msg_pl->sg.size - orig_size);
1134 fallback_to_reg_send:
1135                         sk_msg_trim(sk, msg_pl, orig_size);
1136                 }
1137
1138                 required_size = msg_pl->sg.size + try_to_copy;
1139
1140                 ret = tls_clone_plaintext_msg(sk, required_size);
1141                 if (ret) {
1142                         if (ret != -ENOSPC)
1143                                 goto send_end;
1144
1145                         /* Adjust try_to_copy according to the amount that was
1146                          * actually allocated. The difference is due
1147                          * to max sg elements limit
1148                          */
1149                         try_to_copy -= required_size - msg_pl->sg.size;
1150                         full_record = true;
1151                         sk_msg_trim(sk, msg_en,
1152                                     msg_pl->sg.size + prot->overhead_size);
1153                 }
1154
1155                 if (try_to_copy) {
1156                         ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter,
1157                                                        msg_pl, try_to_copy);
1158                         if (ret < 0)
1159                                 goto trim_sgl;
1160                 }
1161
1162                 /* Open records defined only if successfully copied, otherwise
1163                  * we would trim the sg but not reset the open record frags.
1164                  */
1165                 tls_ctx->pending_open_record_frags = true;
1166                 copied += try_to_copy;
1167 copied:
1168                 if (full_record || eor) {
1169                         ret = bpf_exec_tx_verdict(msg_pl, sk, full_record,
1170                                                   record_type, &copied,
1171                                                   msg->msg_flags);
1172                         if (ret) {
1173                                 if (ret == -EINPROGRESS)
1174                                         num_async++;
1175                                 else if (ret == -ENOMEM)
1176                                         goto wait_for_memory;
1177                                 else if (ret != -EAGAIN) {
1178                                         if (ret == -ENOSPC)
1179                                                 ret = 0;
1180                                         goto send_end;
1181                                 }
1182                         }
1183                 }
1184
1185                 continue;
1186
1187 wait_for_sndbuf:
1188                 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1189 wait_for_memory:
1190                 ret = sk_stream_wait_memory(sk, &timeo);
1191                 if (ret) {
1192 trim_sgl:
1193                         if (ctx->open_rec)
1194                                 tls_trim_both_msgs(sk, orig_size);
1195                         goto send_end;
1196                 }
1197
1198                 if (ctx->open_rec && msg_en->sg.size < required_size)
1199                         goto alloc_encrypted;
1200         }
1201
1202         if (!num_async) {
1203                 goto send_end;
1204         } else if (num_zc) {
1205                 int err;
1206
1207                 /* Wait for pending encryptions to get completed */
1208                 err = tls_encrypt_async_wait(ctx);
1209                 if (err) {
1210                         ret = err;
1211                         copied = 0;
1212                 }
1213         }
1214
1215         /* Transmit if any encryptions have completed */
1216         if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1217                 cancel_delayed_work(&ctx->tx_work.work);
1218                 tls_tx_records(sk, msg->msg_flags);
1219         }
1220
1221 send_end:
1222         ret = sk_stream_error(sk, msg->msg_flags, ret);
1223         return copied > 0 ? copied : ret;
1224 }
1225
1226 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
1227 {
1228         struct tls_context *tls_ctx = tls_get_ctx(sk);
1229         int ret;
1230
1231         if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL |
1232                                MSG_CMSG_COMPAT | MSG_SPLICE_PAGES | MSG_EOR |
1233                                MSG_SENDPAGE_NOPOLICY))
1234                 return -EOPNOTSUPP;
1235
1236         ret = mutex_lock_interruptible(&tls_ctx->tx_lock);
1237         if (ret)
1238                 return ret;
1239         lock_sock(sk);
1240         ret = tls_sw_sendmsg_locked(sk, msg, size);
1241         release_sock(sk);
1242         mutex_unlock(&tls_ctx->tx_lock);
1243         return ret;
1244 }
1245
1246 /*
1247  * Handle unexpected EOF during splice without SPLICE_F_MORE set.
1248  */
1249 void tls_sw_splice_eof(struct socket *sock)
1250 {
1251         struct sock *sk = sock->sk;
1252         struct tls_context *tls_ctx = tls_get_ctx(sk);
1253         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
1254         struct tls_rec *rec;
1255         struct sk_msg *msg_pl;
1256         ssize_t copied = 0;
1257         bool retrying = false;
1258         int ret = 0;
1259
1260         if (!ctx->open_rec)
1261                 return;
1262
1263         mutex_lock(&tls_ctx->tx_lock);
1264         lock_sock(sk);
1265
1266 retry:
1267         /* same checks as in tls_sw_push_pending_record() */
1268         rec = ctx->open_rec;
1269         if (!rec)
1270                 goto unlock;
1271
1272         msg_pl = &rec->msg_plaintext;
1273         if (msg_pl->sg.size == 0)
1274                 goto unlock;
1275
1276         /* Check the BPF advisor and perform transmission. */
1277         ret = bpf_exec_tx_verdict(msg_pl, sk, false, TLS_RECORD_TYPE_DATA,
1278                                   &copied, 0);
1279         switch (ret) {
1280         case 0:
1281         case -EAGAIN:
1282                 if (retrying)
1283                         goto unlock;
1284                 retrying = true;
1285                 goto retry;
1286         case -EINPROGRESS:
1287                 break;
1288         default:
1289                 goto unlock;
1290         }
1291
1292         /* Wait for pending encryptions to get completed */
1293         if (tls_encrypt_async_wait(ctx))
1294                 goto unlock;
1295
1296         /* Transmit if any encryptions have completed */
1297         if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
1298                 cancel_delayed_work(&ctx->tx_work.work);
1299                 tls_tx_records(sk, 0);
1300         }
1301
1302 unlock:
1303         release_sock(sk);
1304         mutex_unlock(&tls_ctx->tx_lock);
1305 }
1306
1307 static int
1308 tls_rx_rec_wait(struct sock *sk, struct sk_psock *psock, bool nonblock,
1309                 bool released)
1310 {
1311         struct tls_context *tls_ctx = tls_get_ctx(sk);
1312         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1313         DEFINE_WAIT_FUNC(wait, woken_wake_function);
1314         int ret = 0;
1315         long timeo;
1316
1317         timeo = sock_rcvtimeo(sk, nonblock);
1318
1319         while (!tls_strp_msg_ready(ctx)) {
1320                 if (!sk_psock_queue_empty(psock))
1321                         return 0;
1322
1323                 if (sk->sk_err)
1324                         return sock_error(sk);
1325
1326                 if (ret < 0)
1327                         return ret;
1328
1329                 if (!skb_queue_empty(&sk->sk_receive_queue)) {
1330                         tls_strp_check_rcv(&ctx->strp);
1331                         if (tls_strp_msg_ready(ctx))
1332                                 break;
1333                 }
1334
1335                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1336                         return 0;
1337
1338                 if (sock_flag(sk, SOCK_DONE))
1339                         return 0;
1340
1341                 if (!timeo)
1342                         return -EAGAIN;
1343
1344                 released = true;
1345                 add_wait_queue(sk_sleep(sk), &wait);
1346                 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1347                 ret = sk_wait_event(sk, &timeo,
1348                                     tls_strp_msg_ready(ctx) ||
1349                                     !sk_psock_queue_empty(psock),
1350                                     &wait);
1351                 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
1352                 remove_wait_queue(sk_sleep(sk), &wait);
1353
1354                 /* Handle signals */
1355                 if (signal_pending(current))
1356                         return sock_intr_errno(timeo);
1357         }
1358
1359         tls_strp_msg_load(&ctx->strp, released);
1360
1361         return 1;
1362 }
1363
1364 static int tls_setup_from_iter(struct iov_iter *from,
1365                                int length, int *pages_used,
1366                                struct scatterlist *to,
1367                                int to_max_pages)
1368 {
1369         int rc = 0, i = 0, num_elem = *pages_used, maxpages;
1370         struct page *pages[MAX_SKB_FRAGS];
1371         unsigned int size = 0;
1372         ssize_t copied, use;
1373         size_t offset;
1374
1375         while (length > 0) {
1376                 i = 0;
1377                 maxpages = to_max_pages - num_elem;
1378                 if (maxpages == 0) {
1379                         rc = -EFAULT;
1380                         goto out;
1381                 }
1382                 copied = iov_iter_get_pages2(from, pages,
1383                                             length,
1384                                             maxpages, &offset);
1385                 if (copied <= 0) {
1386                         rc = -EFAULT;
1387                         goto out;
1388                 }
1389
1390                 length -= copied;
1391                 size += copied;
1392                 while (copied) {
1393                         use = min_t(int, copied, PAGE_SIZE - offset);
1394
1395                         sg_set_page(&to[num_elem],
1396                                     pages[i], use, offset);
1397                         sg_unmark_end(&to[num_elem]);
1398                         /* We do not uncharge memory from this API */
1399
1400                         offset = 0;
1401                         copied -= use;
1402
1403                         i++;
1404                         num_elem++;
1405                 }
1406         }
1407         /* Mark the end in the last sg entry if newly added */
1408         if (num_elem > *pages_used)
1409                 sg_mark_end(&to[num_elem - 1]);
1410 out:
1411         if (rc)
1412                 iov_iter_revert(from, size);
1413         *pages_used = num_elem;
1414
1415         return rc;
1416 }
1417
1418 static struct sk_buff *
1419 tls_alloc_clrtxt_skb(struct sock *sk, struct sk_buff *skb,
1420                      unsigned int full_len)
1421 {
1422         struct strp_msg *clr_rxm;
1423         struct sk_buff *clr_skb;
1424         int err;
1425
1426         clr_skb = alloc_skb_with_frags(0, full_len, TLS_PAGE_ORDER,
1427                                        &err, sk->sk_allocation);
1428         if (!clr_skb)
1429                 return NULL;
1430
1431         skb_copy_header(clr_skb, skb);
1432         clr_skb->len = full_len;
1433         clr_skb->data_len = full_len;
1434
1435         clr_rxm = strp_msg(clr_skb);
1436         clr_rxm->offset = 0;
1437
1438         return clr_skb;
1439 }
1440
1441 /* Decrypt handlers
1442  *
1443  * tls_decrypt_sw() and tls_decrypt_device() are decrypt handlers.
1444  * They must transform the darg in/out argument are as follows:
1445  *       |          Input            |         Output
1446  * -------------------------------------------------------------------
1447  *    zc | Zero-copy decrypt allowed | Zero-copy performed
1448  * async | Async decrypt allowed     | Async crypto used / in progress
1449  *   skb |            *              | Output skb
1450  *
1451  * If ZC decryption was performed darg.skb will point to the input skb.
1452  */
1453
1454 /* This function decrypts the input skb into either out_iov or in out_sg
1455  * or in skb buffers itself. The input parameter 'darg->zc' indicates if
1456  * zero-copy mode needs to be tried or not. With zero-copy mode, either
1457  * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are
1458  * NULL, then the decryption happens inside skb buffers itself, i.e.
1459  * zero-copy gets disabled and 'darg->zc' is updated.
1460  */
1461 static int tls_decrypt_sg(struct sock *sk, struct iov_iter *out_iov,
1462                           struct scatterlist *out_sg,
1463                           struct tls_decrypt_arg *darg)
1464 {
1465         struct tls_context *tls_ctx = tls_get_ctx(sk);
1466         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1467         struct tls_prot_info *prot = &tls_ctx->prot_info;
1468         int n_sgin, n_sgout, aead_size, err, pages = 0;
1469         struct sk_buff *skb = tls_strp_msg(ctx);
1470         const struct strp_msg *rxm = strp_msg(skb);
1471         const struct tls_msg *tlm = tls_msg(skb);
1472         struct aead_request *aead_req;
1473         struct scatterlist *sgin = NULL;
1474         struct scatterlist *sgout = NULL;
1475         const int data_len = rxm->full_len - prot->overhead_size;
1476         int tail_pages = !!prot->tail_size;
1477         struct tls_decrypt_ctx *dctx;
1478         struct sk_buff *clear_skb;
1479         int iv_offset = 0;
1480         u8 *mem;
1481
1482         n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size,
1483                          rxm->full_len - prot->prepend_size);
1484         if (n_sgin < 1)
1485                 return n_sgin ?: -EBADMSG;
1486
1487         if (darg->zc && (out_iov || out_sg)) {
1488                 clear_skb = NULL;
1489
1490                 if (out_iov)
1491                         n_sgout = 1 + tail_pages +
1492                                 iov_iter_npages_cap(out_iov, INT_MAX, data_len);
1493                 else
1494                         n_sgout = sg_nents(out_sg);
1495         } else {
1496                 darg->zc = false;
1497
1498                 clear_skb = tls_alloc_clrtxt_skb(sk, skb, rxm->full_len);
1499                 if (!clear_skb)
1500                         return -ENOMEM;
1501
1502                 n_sgout = 1 + skb_shinfo(clear_skb)->nr_frags;
1503         }
1504
1505         /* Increment to accommodate AAD */
1506         n_sgin = n_sgin + 1;
1507
1508         /* Allocate a single block of memory which contains
1509          *   aead_req || tls_decrypt_ctx.
1510          * Both structs are variable length.
1511          */
1512         aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
1513         aead_size = ALIGN(aead_size, __alignof__(*dctx));
1514         mem = kmalloc(aead_size + struct_size(dctx, sg, size_add(n_sgin, n_sgout)),
1515                       sk->sk_allocation);
1516         if (!mem) {
1517                 err = -ENOMEM;
1518                 goto exit_free_skb;
1519         }
1520
1521         /* Segment the allocated memory */
1522         aead_req = (struct aead_request *)mem;
1523         dctx = (struct tls_decrypt_ctx *)(mem + aead_size);
1524         dctx->sk = sk;
1525         sgin = &dctx->sg[0];
1526         sgout = &dctx->sg[n_sgin];
1527
1528         /* For CCM based ciphers, first byte of nonce+iv is a constant */
1529         switch (prot->cipher_type) {
1530         case TLS_CIPHER_AES_CCM_128:
1531                 dctx->iv[0] = TLS_AES_CCM_IV_B0_BYTE;
1532                 iv_offset = 1;
1533                 break;
1534         case TLS_CIPHER_SM4_CCM:
1535                 dctx->iv[0] = TLS_SM4_CCM_IV_B0_BYTE;
1536                 iv_offset = 1;
1537                 break;
1538         }
1539
1540         /* Prepare IV */
1541         if (prot->version == TLS_1_3_VERSION ||
1542             prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) {
1543                 memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv,
1544                        prot->iv_size + prot->salt_size);
1545         } else {
1546                 err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
1547                                     &dctx->iv[iv_offset] + prot->salt_size,
1548                                     prot->iv_size);
1549                 if (err < 0)
1550                         goto exit_free;
1551                 memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv, prot->salt_size);
1552         }
1553         tls_xor_iv_with_seq(prot, &dctx->iv[iv_offset], tls_ctx->rx.rec_seq);
1554
1555         /* Prepare AAD */
1556         tls_make_aad(dctx->aad, rxm->full_len - prot->overhead_size +
1557                      prot->tail_size,
1558                      tls_ctx->rx.rec_seq, tlm->control, prot);
1559
1560         /* Prepare sgin */
1561         sg_init_table(sgin, n_sgin);
1562         sg_set_buf(&sgin[0], dctx->aad, prot->aad_size);
1563         err = skb_to_sgvec(skb, &sgin[1],
1564                            rxm->offset + prot->prepend_size,
1565                            rxm->full_len - prot->prepend_size);
1566         if (err < 0)
1567                 goto exit_free;
1568
1569         if (clear_skb) {
1570                 sg_init_table(sgout, n_sgout);
1571                 sg_set_buf(&sgout[0], dctx->aad, prot->aad_size);
1572
1573                 err = skb_to_sgvec(clear_skb, &sgout[1], prot->prepend_size,
1574                                    data_len + prot->tail_size);
1575                 if (err < 0)
1576                         goto exit_free;
1577         } else if (out_iov) {
1578                 sg_init_table(sgout, n_sgout);
1579                 sg_set_buf(&sgout[0], dctx->aad, prot->aad_size);
1580
1581                 err = tls_setup_from_iter(out_iov, data_len, &pages, &sgout[1],
1582                                           (n_sgout - 1 - tail_pages));
1583                 if (err < 0)
1584                         goto exit_free_pages;
1585
1586                 if (prot->tail_size) {
1587                         sg_unmark_end(&sgout[pages]);
1588                         sg_set_buf(&sgout[pages + 1], &dctx->tail,
1589                                    prot->tail_size);
1590                         sg_mark_end(&sgout[pages + 1]);
1591                 }
1592         } else if (out_sg) {
1593                 memcpy(sgout, out_sg, n_sgout * sizeof(*sgout));
1594         }
1595         dctx->free_sgout = !!pages;
1596
1597         /* Prepare and submit AEAD request */
1598         err = tls_do_decryption(sk, sgin, sgout, dctx->iv,
1599                                 data_len + prot->tail_size, aead_req, darg);
1600         if (err) {
1601                 if (darg->async_done)
1602                         goto exit_free_skb;
1603                 goto exit_free_pages;
1604         }
1605
1606         darg->skb = clear_skb ?: tls_strp_msg(ctx);
1607         clear_skb = NULL;
1608
1609         if (unlikely(darg->async)) {
1610                 err = tls_strp_msg_hold(&ctx->strp, &ctx->async_hold);
1611                 if (err)
1612                         __skb_queue_tail(&ctx->async_hold, darg->skb);
1613                 return err;
1614         }
1615
1616         if (unlikely(darg->async_done))
1617                 return 0;
1618
1619         if (prot->tail_size)
1620                 darg->tail = dctx->tail;
1621
1622 exit_free_pages:
1623         /* Release the pages in case iov was mapped to pages */
1624         for (; pages > 0; pages--)
1625                 put_page(sg_page(&sgout[pages]));
1626 exit_free:
1627         kfree(mem);
1628 exit_free_skb:
1629         consume_skb(clear_skb);
1630         return err;
1631 }
1632
1633 static int
1634 tls_decrypt_sw(struct sock *sk, struct tls_context *tls_ctx,
1635                struct msghdr *msg, struct tls_decrypt_arg *darg)
1636 {
1637         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1638         struct tls_prot_info *prot = &tls_ctx->prot_info;
1639         struct strp_msg *rxm;
1640         int pad, err;
1641
1642         err = tls_decrypt_sg(sk, &msg->msg_iter, NULL, darg);
1643         if (err < 0) {
1644                 if (err == -EBADMSG)
1645                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR);
1646                 return err;
1647         }
1648         /* keep going even for ->async, the code below is TLS 1.3 */
1649
1650         /* If opportunistic TLS 1.3 ZC failed retry without ZC */
1651         if (unlikely(darg->zc && prot->version == TLS_1_3_VERSION &&
1652                      darg->tail != TLS_RECORD_TYPE_DATA)) {
1653                 darg->zc = false;
1654                 if (!darg->tail)
1655                         TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXNOPADVIOL);
1656                 TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTRETRY);
1657                 return tls_decrypt_sw(sk, tls_ctx, msg, darg);
1658         }
1659
1660         pad = tls_padding_length(prot, darg->skb, darg);
1661         if (pad < 0) {
1662                 if (darg->skb != tls_strp_msg(ctx))
1663                         consume_skb(darg->skb);
1664                 return pad;
1665         }
1666
1667         rxm = strp_msg(darg->skb);
1668         rxm->full_len -= pad;
1669
1670         return 0;
1671 }
1672
1673 static int
1674 tls_decrypt_device(struct sock *sk, struct msghdr *msg,
1675                    struct tls_context *tls_ctx, struct tls_decrypt_arg *darg)
1676 {
1677         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1678         struct tls_prot_info *prot = &tls_ctx->prot_info;
1679         struct strp_msg *rxm;
1680         int pad, err;
1681
1682         if (tls_ctx->rx_conf != TLS_HW)
1683                 return 0;
1684
1685         err = tls_device_decrypted(sk, tls_ctx);
1686         if (err <= 0)
1687                 return err;
1688
1689         pad = tls_padding_length(prot, tls_strp_msg(ctx), darg);
1690         if (pad < 0)
1691                 return pad;
1692
1693         darg->async = false;
1694         darg->skb = tls_strp_msg(ctx);
1695         /* ->zc downgrade check, in case TLS 1.3 gets here */
1696         darg->zc &= !(prot->version == TLS_1_3_VERSION &&
1697                       tls_msg(darg->skb)->control != TLS_RECORD_TYPE_DATA);
1698
1699         rxm = strp_msg(darg->skb);
1700         rxm->full_len -= pad;
1701
1702         if (!darg->zc) {
1703                 /* Non-ZC case needs a real skb */
1704                 darg->skb = tls_strp_msg_detach(ctx);
1705                 if (!darg->skb)
1706                         return -ENOMEM;
1707         } else {
1708                 unsigned int off, len;
1709
1710                 /* In ZC case nobody cares about the output skb.
1711                  * Just copy the data here. Note the skb is not fully trimmed.
1712                  */
1713                 off = rxm->offset + prot->prepend_size;
1714                 len = rxm->full_len - prot->overhead_size;
1715
1716                 err = skb_copy_datagram_msg(darg->skb, off, msg, len);
1717                 if (err)
1718                         return err;
1719         }
1720         return 1;
1721 }
1722
1723 static int tls_rx_one_record(struct sock *sk, struct msghdr *msg,
1724                              struct tls_decrypt_arg *darg)
1725 {
1726         struct tls_context *tls_ctx = tls_get_ctx(sk);
1727         struct tls_prot_info *prot = &tls_ctx->prot_info;
1728         struct strp_msg *rxm;
1729         int err;
1730
1731         err = tls_decrypt_device(sk, msg, tls_ctx, darg);
1732         if (!err)
1733                 err = tls_decrypt_sw(sk, tls_ctx, msg, darg);
1734         if (err < 0)
1735                 return err;
1736
1737         rxm = strp_msg(darg->skb);
1738         rxm->offset += prot->prepend_size;
1739         rxm->full_len -= prot->overhead_size;
1740         tls_advance_record_sn(sk, prot, &tls_ctx->rx);
1741
1742         return 0;
1743 }
1744
1745 int decrypt_skb(struct sock *sk, struct scatterlist *sgout)
1746 {
1747         struct tls_decrypt_arg darg = { .zc = true, };
1748
1749         return tls_decrypt_sg(sk, NULL, sgout, &darg);
1750 }
1751
1752 static int tls_record_content_type(struct msghdr *msg, struct tls_msg *tlm,
1753                                    u8 *control)
1754 {
1755         int err;
1756
1757         if (!*control) {
1758                 *control = tlm->control;
1759                 if (!*control)
1760                         return -EBADMSG;
1761
1762                 err = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE,
1763                                sizeof(*control), control);
1764                 if (*control != TLS_RECORD_TYPE_DATA) {
1765                         if (err || msg->msg_flags & MSG_CTRUNC)
1766                                 return -EIO;
1767                 }
1768         } else if (*control != tlm->control) {
1769                 return 0;
1770         }
1771
1772         return 1;
1773 }
1774
1775 static void tls_rx_rec_done(struct tls_sw_context_rx *ctx)
1776 {
1777         tls_strp_msg_done(&ctx->strp);
1778 }
1779
1780 /* This function traverses the rx_list in tls receive context to copies the
1781  * decrypted records into the buffer provided by caller zero copy is not
1782  * true. Further, the records are removed from the rx_list if it is not a peek
1783  * case and the record has been consumed completely.
1784  */
1785 static int process_rx_list(struct tls_sw_context_rx *ctx,
1786                            struct msghdr *msg,
1787                            u8 *control,
1788                            size_t skip,
1789                            size_t len,
1790                            bool is_peek,
1791                            bool *more)
1792 {
1793         struct sk_buff *skb = skb_peek(&ctx->rx_list);
1794         struct tls_msg *tlm;
1795         ssize_t copied = 0;
1796         int err;
1797
1798         while (skip && skb) {
1799                 struct strp_msg *rxm = strp_msg(skb);
1800                 tlm = tls_msg(skb);
1801
1802                 err = tls_record_content_type(msg, tlm, control);
1803                 if (err <= 0)
1804                         goto more;
1805
1806                 if (skip < rxm->full_len)
1807                         break;
1808
1809                 skip = skip - rxm->full_len;
1810                 skb = skb_peek_next(skb, &ctx->rx_list);
1811         }
1812
1813         while (len && skb) {
1814                 struct sk_buff *next_skb;
1815                 struct strp_msg *rxm = strp_msg(skb);
1816                 int chunk = min_t(unsigned int, rxm->full_len - skip, len);
1817
1818                 tlm = tls_msg(skb);
1819
1820                 err = tls_record_content_type(msg, tlm, control);
1821                 if (err <= 0)
1822                         goto more;
1823
1824                 err = skb_copy_datagram_msg(skb, rxm->offset + skip,
1825                                             msg, chunk);
1826                 if (err < 0)
1827                         goto more;
1828
1829                 len = len - chunk;
1830                 copied = copied + chunk;
1831
1832                 /* Consume the data from record if it is non-peek case*/
1833                 if (!is_peek) {
1834                         rxm->offset = rxm->offset + chunk;
1835                         rxm->full_len = rxm->full_len - chunk;
1836
1837                         /* Return if there is unconsumed data in the record */
1838                         if (rxm->full_len - skip)
1839                                 break;
1840                 }
1841
1842                 /* The remaining skip-bytes must lie in 1st record in rx_list.
1843                  * So from the 2nd record, 'skip' should be 0.
1844                  */
1845                 skip = 0;
1846
1847                 if (msg)
1848                         msg->msg_flags |= MSG_EOR;
1849
1850                 next_skb = skb_peek_next(skb, &ctx->rx_list);
1851
1852                 if (!is_peek) {
1853                         __skb_unlink(skb, &ctx->rx_list);
1854                         consume_skb(skb);
1855                 }
1856
1857                 skb = next_skb;
1858         }
1859         err = 0;
1860
1861 out:
1862         return copied ? : err;
1863 more:
1864         if (more)
1865                 *more = true;
1866         goto out;
1867 }
1868
1869 static bool
1870 tls_read_flush_backlog(struct sock *sk, struct tls_prot_info *prot,
1871                        size_t len_left, size_t decrypted, ssize_t done,
1872                        size_t *flushed_at)
1873 {
1874         size_t max_rec;
1875
1876         if (len_left <= decrypted)
1877                 return false;
1878
1879         max_rec = prot->overhead_size - prot->tail_size + TLS_MAX_PAYLOAD_SIZE;
1880         if (done - *flushed_at < SZ_128K && tcp_inq(sk) > max_rec)
1881                 return false;
1882
1883         *flushed_at = done;
1884         return sk_flush_backlog(sk);
1885 }
1886
1887 static int tls_rx_reader_acquire(struct sock *sk, struct tls_sw_context_rx *ctx,
1888                                  bool nonblock)
1889 {
1890         long timeo;
1891         int ret;
1892
1893         timeo = sock_rcvtimeo(sk, nonblock);
1894
1895         while (unlikely(ctx->reader_present)) {
1896                 DEFINE_WAIT_FUNC(wait, woken_wake_function);
1897
1898                 ctx->reader_contended = 1;
1899
1900                 add_wait_queue(&ctx->wq, &wait);
1901                 ret = sk_wait_event(sk, &timeo,
1902                                     !READ_ONCE(ctx->reader_present), &wait);
1903                 remove_wait_queue(&ctx->wq, &wait);
1904
1905                 if (timeo <= 0)
1906                         return -EAGAIN;
1907                 if (signal_pending(current))
1908                         return sock_intr_errno(timeo);
1909                 if (ret < 0)
1910                         return ret;
1911         }
1912
1913         WRITE_ONCE(ctx->reader_present, 1);
1914
1915         return 0;
1916 }
1917
1918 static int tls_rx_reader_lock(struct sock *sk, struct tls_sw_context_rx *ctx,
1919                               bool nonblock)
1920 {
1921         int err;
1922
1923         lock_sock(sk);
1924         err = tls_rx_reader_acquire(sk, ctx, nonblock);
1925         if (err)
1926                 release_sock(sk);
1927         return err;
1928 }
1929
1930 static void tls_rx_reader_release(struct sock *sk, struct tls_sw_context_rx *ctx)
1931 {
1932         if (unlikely(ctx->reader_contended)) {
1933                 if (wq_has_sleeper(&ctx->wq))
1934                         wake_up(&ctx->wq);
1935                 else
1936                         ctx->reader_contended = 0;
1937
1938                 WARN_ON_ONCE(!ctx->reader_present);
1939         }
1940
1941         WRITE_ONCE(ctx->reader_present, 0);
1942 }
1943
1944 static void tls_rx_reader_unlock(struct sock *sk, struct tls_sw_context_rx *ctx)
1945 {
1946         tls_rx_reader_release(sk, ctx);
1947         release_sock(sk);
1948 }
1949
1950 int tls_sw_recvmsg(struct sock *sk,
1951                    struct msghdr *msg,
1952                    size_t len,
1953                    int flags,
1954                    int *addr_len)
1955 {
1956         struct tls_context *tls_ctx = tls_get_ctx(sk);
1957         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
1958         struct tls_prot_info *prot = &tls_ctx->prot_info;
1959         ssize_t decrypted = 0, async_copy_bytes = 0;
1960         struct sk_psock *psock;
1961         unsigned char control = 0;
1962         size_t flushed_at = 0;
1963         struct strp_msg *rxm;
1964         struct tls_msg *tlm;
1965         ssize_t copied = 0;
1966         ssize_t peeked = 0;
1967         bool async = false;
1968         int target, err;
1969         bool is_kvec = iov_iter_is_kvec(&msg->msg_iter);
1970         bool is_peek = flags & MSG_PEEK;
1971         bool rx_more = false;
1972         bool released = true;
1973         bool bpf_strp_enabled;
1974         bool zc_capable;
1975
1976         if (unlikely(flags & MSG_ERRQUEUE))
1977                 return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR);
1978
1979         err = tls_rx_reader_lock(sk, ctx, flags & MSG_DONTWAIT);
1980         if (err < 0)
1981                 return err;
1982         psock = sk_psock_get(sk);
1983         bpf_strp_enabled = sk_psock_strp_enabled(psock);
1984
1985         /* If crypto failed the connection is broken */
1986         err = ctx->async_wait.err;
1987         if (err)
1988                 goto end;
1989
1990         /* Process pending decrypted records. It must be non-zero-copy */
1991         err = process_rx_list(ctx, msg, &control, 0, len, is_peek, &rx_more);
1992         if (err < 0)
1993                 goto end;
1994
1995         copied = err;
1996         if (len <= copied || (copied && control != TLS_RECORD_TYPE_DATA) || rx_more)
1997                 goto end;
1998
1999         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
2000         len = len - copied;
2001
2002         zc_capable = !bpf_strp_enabled && !is_kvec && !is_peek &&
2003                 ctx->zc_capable;
2004         decrypted = 0;
2005         while (len && (decrypted + copied < target || tls_strp_msg_ready(ctx))) {
2006                 struct tls_decrypt_arg darg;
2007                 int to_decrypt, chunk;
2008
2009                 err = tls_rx_rec_wait(sk, psock, flags & MSG_DONTWAIT,
2010                                       released);
2011                 if (err <= 0) {
2012                         if (psock) {
2013                                 chunk = sk_msg_recvmsg(sk, psock, msg, len,
2014                                                        flags);
2015                                 if (chunk > 0) {
2016                                         decrypted += chunk;
2017                                         len -= chunk;
2018                                         continue;
2019                                 }
2020                         }
2021                         goto recv_end;
2022                 }
2023
2024                 memset(&darg.inargs, 0, sizeof(darg.inargs));
2025
2026                 rxm = strp_msg(tls_strp_msg(ctx));
2027                 tlm = tls_msg(tls_strp_msg(ctx));
2028
2029                 to_decrypt = rxm->full_len - prot->overhead_size;
2030
2031                 if (zc_capable && to_decrypt <= len &&
2032                     tlm->control == TLS_RECORD_TYPE_DATA)
2033                         darg.zc = true;
2034
2035                 /* Do not use async mode if record is non-data */
2036                 if (tlm->control == TLS_RECORD_TYPE_DATA && !bpf_strp_enabled)
2037                         darg.async = ctx->async_capable;
2038                 else
2039                         darg.async = false;
2040
2041                 err = tls_rx_one_record(sk, msg, &darg);
2042                 if (err < 0) {
2043                         tls_err_abort(sk, -EBADMSG);
2044                         goto recv_end;
2045                 }
2046
2047                 async |= darg.async;
2048
2049                 /* If the type of records being processed is not known yet,
2050                  * set it to record type just dequeued. If it is already known,
2051                  * but does not match the record type just dequeued, go to end.
2052                  * We always get record type here since for tls1.2, record type
2053                  * is known just after record is dequeued from stream parser.
2054                  * For tls1.3, we disable async.
2055                  */
2056                 err = tls_record_content_type(msg, tls_msg(darg.skb), &control);
2057                 if (err <= 0) {
2058                         DEBUG_NET_WARN_ON_ONCE(darg.zc);
2059                         tls_rx_rec_done(ctx);
2060 put_on_rx_list_err:
2061                         __skb_queue_tail(&ctx->rx_list, darg.skb);
2062                         goto recv_end;
2063                 }
2064
2065                 /* periodically flush backlog, and feed strparser */
2066                 released = tls_read_flush_backlog(sk, prot, len, to_decrypt,
2067                                                   decrypted + copied,
2068                                                   &flushed_at);
2069
2070                 /* TLS 1.3 may have updated the length by more than overhead */
2071                 rxm = strp_msg(darg.skb);
2072                 chunk = rxm->full_len;
2073                 tls_rx_rec_done(ctx);
2074
2075                 if (!darg.zc) {
2076                         bool partially_consumed = chunk > len;
2077                         struct sk_buff *skb = darg.skb;
2078
2079                         DEBUG_NET_WARN_ON_ONCE(darg.skb == ctx->strp.anchor);
2080
2081                         if (async) {
2082                                 /* TLS 1.2-only, to_decrypt must be text len */
2083                                 chunk = min_t(int, to_decrypt, len);
2084                                 async_copy_bytes += chunk;
2085 put_on_rx_list:
2086                                 decrypted += chunk;
2087                                 len -= chunk;
2088                                 __skb_queue_tail(&ctx->rx_list, skb);
2089                                 if (unlikely(control != TLS_RECORD_TYPE_DATA))
2090                                         break;
2091                                 continue;
2092                         }
2093
2094                         if (bpf_strp_enabled) {
2095                                 released = true;
2096                                 err = sk_psock_tls_strp_read(psock, skb);
2097                                 if (err != __SK_PASS) {
2098                                         rxm->offset = rxm->offset + rxm->full_len;
2099                                         rxm->full_len = 0;
2100                                         if (err == __SK_DROP)
2101                                                 consume_skb(skb);
2102                                         continue;
2103                                 }
2104                         }
2105
2106                         if (partially_consumed)
2107                                 chunk = len;
2108
2109                         err = skb_copy_datagram_msg(skb, rxm->offset,
2110                                                     msg, chunk);
2111                         if (err < 0)
2112                                 goto put_on_rx_list_err;
2113
2114                         if (is_peek) {
2115                                 peeked += chunk;
2116                                 goto put_on_rx_list;
2117                         }
2118
2119                         if (partially_consumed) {
2120                                 rxm->offset += chunk;
2121                                 rxm->full_len -= chunk;
2122                                 goto put_on_rx_list;
2123                         }
2124
2125                         consume_skb(skb);
2126                 }
2127
2128                 decrypted += chunk;
2129                 len -= chunk;
2130
2131                 /* Return full control message to userspace before trying
2132                  * to parse another message type
2133                  */
2134                 msg->msg_flags |= MSG_EOR;
2135                 if (control != TLS_RECORD_TYPE_DATA)
2136                         break;
2137         }
2138
2139 recv_end:
2140         if (async) {
2141                 int ret;
2142
2143                 /* Wait for all previously submitted records to be decrypted */
2144                 ret = tls_decrypt_async_wait(ctx);
2145                 __skb_queue_purge(&ctx->async_hold);
2146
2147                 if (ret) {
2148                         if (err >= 0 || err == -EINPROGRESS)
2149                                 err = ret;
2150                         decrypted = 0;
2151                         goto end;
2152                 }
2153
2154                 /* Drain records from the rx_list & copy if required */
2155                 if (is_peek)
2156                         err = process_rx_list(ctx, msg, &control, copied + peeked,
2157                                               decrypted - peeked, is_peek, NULL);
2158                 else
2159                         err = process_rx_list(ctx, msg, &control, 0,
2160                                               async_copy_bytes, is_peek, NULL);
2161
2162                 /* we could have copied less than we wanted, and possibly nothing */
2163                 decrypted += max(err, 0) - async_copy_bytes;
2164         }
2165
2166         copied += decrypted;
2167
2168 end:
2169         tls_rx_reader_unlock(sk, ctx);
2170         if (psock)
2171                 sk_psock_put(sk, psock);
2172         return copied ? : err;
2173 }
2174
2175 ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
2176                            struct pipe_inode_info *pipe,
2177                            size_t len, unsigned int flags)
2178 {
2179         struct tls_context *tls_ctx = tls_get_ctx(sock->sk);
2180         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2181         struct strp_msg *rxm = NULL;
2182         struct sock *sk = sock->sk;
2183         struct tls_msg *tlm;
2184         struct sk_buff *skb;
2185         ssize_t copied = 0;
2186         int chunk;
2187         int err;
2188
2189         err = tls_rx_reader_lock(sk, ctx, flags & SPLICE_F_NONBLOCK);
2190         if (err < 0)
2191                 return err;
2192
2193         if (!skb_queue_empty(&ctx->rx_list)) {
2194                 skb = __skb_dequeue(&ctx->rx_list);
2195         } else {
2196                 struct tls_decrypt_arg darg;
2197
2198                 err = tls_rx_rec_wait(sk, NULL, flags & SPLICE_F_NONBLOCK,
2199                                       true);
2200                 if (err <= 0)
2201                         goto splice_read_end;
2202
2203                 memset(&darg.inargs, 0, sizeof(darg.inargs));
2204
2205                 err = tls_rx_one_record(sk, NULL, &darg);
2206                 if (err < 0) {
2207                         tls_err_abort(sk, -EBADMSG);
2208                         goto splice_read_end;
2209                 }
2210
2211                 tls_rx_rec_done(ctx);
2212                 skb = darg.skb;
2213         }
2214
2215         rxm = strp_msg(skb);
2216         tlm = tls_msg(skb);
2217
2218         /* splice does not support reading control messages */
2219         if (tlm->control != TLS_RECORD_TYPE_DATA) {
2220                 err = -EINVAL;
2221                 goto splice_requeue;
2222         }
2223
2224         chunk = min_t(unsigned int, rxm->full_len, len);
2225         copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags);
2226         if (copied < 0)
2227                 goto splice_requeue;
2228
2229         if (chunk < rxm->full_len) {
2230                 rxm->offset += len;
2231                 rxm->full_len -= len;
2232                 goto splice_requeue;
2233         }
2234
2235         consume_skb(skb);
2236
2237 splice_read_end:
2238         tls_rx_reader_unlock(sk, ctx);
2239         return copied ? : err;
2240
2241 splice_requeue:
2242         __skb_queue_head(&ctx->rx_list, skb);
2243         goto splice_read_end;
2244 }
2245
2246 int tls_sw_read_sock(struct sock *sk, read_descriptor_t *desc,
2247                      sk_read_actor_t read_actor)
2248 {
2249         struct tls_context *tls_ctx = tls_get_ctx(sk);
2250         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2251         struct tls_prot_info *prot = &tls_ctx->prot_info;
2252         struct strp_msg *rxm = NULL;
2253         struct sk_buff *skb = NULL;
2254         struct sk_psock *psock;
2255         size_t flushed_at = 0;
2256         bool released = true;
2257         struct tls_msg *tlm;
2258         ssize_t copied = 0;
2259         ssize_t decrypted;
2260         int err, used;
2261
2262         psock = sk_psock_get(sk);
2263         if (psock) {
2264                 sk_psock_put(sk, psock);
2265                 return -EINVAL;
2266         }
2267         err = tls_rx_reader_acquire(sk, ctx, true);
2268         if (err < 0)
2269                 return err;
2270
2271         /* If crypto failed the connection is broken */
2272         err = ctx->async_wait.err;
2273         if (err)
2274                 goto read_sock_end;
2275
2276         decrypted = 0;
2277         do {
2278                 if (!skb_queue_empty(&ctx->rx_list)) {
2279                         skb = __skb_dequeue(&ctx->rx_list);
2280                         rxm = strp_msg(skb);
2281                         tlm = tls_msg(skb);
2282                 } else {
2283                         struct tls_decrypt_arg darg;
2284
2285                         err = tls_rx_rec_wait(sk, NULL, true, released);
2286                         if (err <= 0)
2287                                 goto read_sock_end;
2288
2289                         memset(&darg.inargs, 0, sizeof(darg.inargs));
2290
2291                         err = tls_rx_one_record(sk, NULL, &darg);
2292                         if (err < 0) {
2293                                 tls_err_abort(sk, -EBADMSG);
2294                                 goto read_sock_end;
2295                         }
2296
2297                         released = tls_read_flush_backlog(sk, prot, INT_MAX,
2298                                                           0, decrypted,
2299                                                           &flushed_at);
2300                         skb = darg.skb;
2301                         rxm = strp_msg(skb);
2302                         tlm = tls_msg(skb);
2303                         decrypted += rxm->full_len;
2304
2305                         tls_rx_rec_done(ctx);
2306                 }
2307
2308                 /* read_sock does not support reading control messages */
2309                 if (tlm->control != TLS_RECORD_TYPE_DATA) {
2310                         err = -EINVAL;
2311                         goto read_sock_requeue;
2312                 }
2313
2314                 used = read_actor(desc, skb, rxm->offset, rxm->full_len);
2315                 if (used <= 0) {
2316                         if (!copied)
2317                                 err = used;
2318                         goto read_sock_requeue;
2319                 }
2320                 copied += used;
2321                 if (used < rxm->full_len) {
2322                         rxm->offset += used;
2323                         rxm->full_len -= used;
2324                         if (!desc->count)
2325                                 goto read_sock_requeue;
2326                 } else {
2327                         consume_skb(skb);
2328                         if (!desc->count)
2329                                 skb = NULL;
2330                 }
2331         } while (skb);
2332
2333 read_sock_end:
2334         tls_rx_reader_release(sk, ctx);
2335         return copied ? : err;
2336
2337 read_sock_requeue:
2338         __skb_queue_head(&ctx->rx_list, skb);
2339         goto read_sock_end;
2340 }
2341
2342 bool tls_sw_sock_is_readable(struct sock *sk)
2343 {
2344         struct tls_context *tls_ctx = tls_get_ctx(sk);
2345         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2346         bool ingress_empty = true;
2347         struct sk_psock *psock;
2348
2349         rcu_read_lock();
2350         psock = sk_psock(sk);
2351         if (psock)
2352                 ingress_empty = list_empty(&psock->ingress_msg);
2353         rcu_read_unlock();
2354
2355         return !ingress_empty || tls_strp_msg_ready(ctx) ||
2356                 !skb_queue_empty(&ctx->rx_list);
2357 }
2358
2359 int tls_rx_msg_size(struct tls_strparser *strp, struct sk_buff *skb)
2360 {
2361         struct tls_context *tls_ctx = tls_get_ctx(strp->sk);
2362         struct tls_prot_info *prot = &tls_ctx->prot_info;
2363         char header[TLS_HEADER_SIZE + TLS_MAX_IV_SIZE];
2364         size_t cipher_overhead;
2365         size_t data_len = 0;
2366         int ret;
2367
2368         /* Verify that we have a full TLS header, or wait for more data */
2369         if (strp->stm.offset + prot->prepend_size > skb->len)
2370                 return 0;
2371
2372         /* Sanity-check size of on-stack buffer. */
2373         if (WARN_ON(prot->prepend_size > sizeof(header))) {
2374                 ret = -EINVAL;
2375                 goto read_failure;
2376         }
2377
2378         /* Linearize header to local buffer */
2379         ret = skb_copy_bits(skb, strp->stm.offset, header, prot->prepend_size);
2380         if (ret < 0)
2381                 goto read_failure;
2382
2383         strp->mark = header[0];
2384
2385         data_len = ((header[4] & 0xFF) | (header[3] << 8));
2386
2387         cipher_overhead = prot->tag_size;
2388         if (prot->version != TLS_1_3_VERSION &&
2389             prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305)
2390                 cipher_overhead += prot->iv_size;
2391
2392         if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead +
2393             prot->tail_size) {
2394                 ret = -EMSGSIZE;
2395                 goto read_failure;
2396         }
2397         if (data_len < cipher_overhead) {
2398                 ret = -EBADMSG;
2399                 goto read_failure;
2400         }
2401
2402         /* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */
2403         if (header[1] != TLS_1_2_VERSION_MINOR ||
2404             header[2] != TLS_1_2_VERSION_MAJOR) {
2405                 ret = -EINVAL;
2406                 goto read_failure;
2407         }
2408
2409         tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE,
2410                                      TCP_SKB_CB(skb)->seq + strp->stm.offset);
2411         return data_len + TLS_HEADER_SIZE;
2412
2413 read_failure:
2414         tls_err_abort(strp->sk, ret);
2415
2416         return ret;
2417 }
2418
2419 void tls_rx_msg_ready(struct tls_strparser *strp)
2420 {
2421         struct tls_sw_context_rx *ctx;
2422
2423         ctx = container_of(strp, struct tls_sw_context_rx, strp);
2424         ctx->saved_data_ready(strp->sk);
2425 }
2426
2427 static void tls_data_ready(struct sock *sk)
2428 {
2429         struct tls_context *tls_ctx = tls_get_ctx(sk);
2430         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2431         struct sk_psock *psock;
2432         gfp_t alloc_save;
2433
2434         trace_sk_data_ready(sk);
2435
2436         alloc_save = sk->sk_allocation;
2437         sk->sk_allocation = GFP_ATOMIC;
2438         tls_strp_data_ready(&ctx->strp);
2439         sk->sk_allocation = alloc_save;
2440
2441         psock = sk_psock_get(sk);
2442         if (psock) {
2443                 if (!list_empty(&psock->ingress_msg))
2444                         ctx->saved_data_ready(sk);
2445                 sk_psock_put(sk, psock);
2446         }
2447 }
2448
2449 void tls_sw_cancel_work_tx(struct tls_context *tls_ctx)
2450 {
2451         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2452
2453         set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask);
2454         set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask);
2455         cancel_delayed_work_sync(&ctx->tx_work.work);
2456 }
2457
2458 void tls_sw_release_resources_tx(struct sock *sk)
2459 {
2460         struct tls_context *tls_ctx = tls_get_ctx(sk);
2461         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2462         struct tls_rec *rec, *tmp;
2463
2464         /* Wait for any pending async encryptions to complete */
2465         tls_encrypt_async_wait(ctx);
2466
2467         tls_tx_records(sk, -1);
2468
2469         /* Free up un-sent records in tx_list. First, free
2470          * the partially sent record if any at head of tx_list.
2471          */
2472         if (tls_ctx->partially_sent_record) {
2473                 tls_free_partial_record(sk, tls_ctx);
2474                 rec = list_first_entry(&ctx->tx_list,
2475                                        struct tls_rec, list);
2476                 list_del(&rec->list);
2477                 sk_msg_free(sk, &rec->msg_plaintext);
2478                 kfree(rec);
2479         }
2480
2481         list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
2482                 list_del(&rec->list);
2483                 sk_msg_free(sk, &rec->msg_encrypted);
2484                 sk_msg_free(sk, &rec->msg_plaintext);
2485                 kfree(rec);
2486         }
2487
2488         crypto_free_aead(ctx->aead_send);
2489         tls_free_open_rec(sk);
2490 }
2491
2492 void tls_sw_free_ctx_tx(struct tls_context *tls_ctx)
2493 {
2494         struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
2495
2496         kfree(ctx);
2497 }
2498
2499 void tls_sw_release_resources_rx(struct sock *sk)
2500 {
2501         struct tls_context *tls_ctx = tls_get_ctx(sk);
2502         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2503
2504         if (ctx->aead_recv) {
2505                 __skb_queue_purge(&ctx->rx_list);
2506                 crypto_free_aead(ctx->aead_recv);
2507                 tls_strp_stop(&ctx->strp);
2508                 /* If tls_sw_strparser_arm() was not called (cleanup paths)
2509                  * we still want to tls_strp_stop(), but sk->sk_data_ready was
2510                  * never swapped.
2511                  */
2512                 if (ctx->saved_data_ready) {
2513                         write_lock_bh(&sk->sk_callback_lock);
2514                         sk->sk_data_ready = ctx->saved_data_ready;
2515                         write_unlock_bh(&sk->sk_callback_lock);
2516                 }
2517         }
2518 }
2519
2520 void tls_sw_strparser_done(struct tls_context *tls_ctx)
2521 {
2522         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2523
2524         tls_strp_done(&ctx->strp);
2525 }
2526
2527 void tls_sw_free_ctx_rx(struct tls_context *tls_ctx)
2528 {
2529         struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
2530
2531         kfree(ctx);
2532 }
2533
2534 void tls_sw_free_resources_rx(struct sock *sk)
2535 {
2536         struct tls_context *tls_ctx = tls_get_ctx(sk);
2537
2538         tls_sw_release_resources_rx(sk);
2539         tls_sw_free_ctx_rx(tls_ctx);
2540 }
2541
2542 /* The work handler to transmitt the encrypted records in tx_list */
2543 static void tx_work_handler(struct work_struct *work)
2544 {
2545         struct delayed_work *delayed_work = to_delayed_work(work);
2546         struct tx_work *tx_work = container_of(delayed_work,
2547                                                struct tx_work, work);
2548         struct sock *sk = tx_work->sk;
2549         struct tls_context *tls_ctx = tls_get_ctx(sk);
2550         struct tls_sw_context_tx *ctx;
2551
2552         if (unlikely(!tls_ctx))
2553                 return;
2554
2555         ctx = tls_sw_ctx_tx(tls_ctx);
2556         if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask))
2557                 return;
2558
2559         if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
2560                 return;
2561
2562         if (mutex_trylock(&tls_ctx->tx_lock)) {
2563                 lock_sock(sk);
2564                 tls_tx_records(sk, -1);
2565                 release_sock(sk);
2566                 mutex_unlock(&tls_ctx->tx_lock);
2567         } else if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) {
2568                 /* Someone is holding the tx_lock, they will likely run Tx
2569                  * and cancel the work on their way out of the lock section.
2570                  * Schedule a long delay just in case.
2571                  */
2572                 schedule_delayed_work(&ctx->tx_work.work, msecs_to_jiffies(10));
2573         }
2574 }
2575
2576 static bool tls_is_tx_ready(struct tls_sw_context_tx *ctx)
2577 {
2578         struct tls_rec *rec;
2579
2580         rec = list_first_entry_or_null(&ctx->tx_list, struct tls_rec, list);
2581         if (!rec)
2582                 return false;
2583
2584         return READ_ONCE(rec->tx_ready);
2585 }
2586
2587 void tls_sw_write_space(struct sock *sk, struct tls_context *ctx)
2588 {
2589         struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx);
2590
2591         /* Schedule the transmission if tx list is ready */
2592         if (tls_is_tx_ready(tx_ctx) &&
2593             !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask))
2594                 schedule_delayed_work(&tx_ctx->tx_work.work, 0);
2595 }
2596
2597 void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx)
2598 {
2599         struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2600
2601         write_lock_bh(&sk->sk_callback_lock);
2602         rx_ctx->saved_data_ready = sk->sk_data_ready;
2603         sk->sk_data_ready = tls_data_ready;
2604         write_unlock_bh(&sk->sk_callback_lock);
2605 }
2606
2607 void tls_update_rx_zc_capable(struct tls_context *tls_ctx)
2608 {
2609         struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx);
2610
2611         rx_ctx->zc_capable = tls_ctx->rx_no_pad ||
2612                 tls_ctx->prot_info.version != TLS_1_3_VERSION;
2613 }
2614
2615 static struct tls_sw_context_tx *init_ctx_tx(struct tls_context *ctx, struct sock *sk)
2616 {
2617         struct tls_sw_context_tx *sw_ctx_tx;
2618
2619         if (!ctx->priv_ctx_tx) {
2620                 sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL);
2621                 if (!sw_ctx_tx)
2622                         return NULL;
2623         } else {
2624                 sw_ctx_tx = ctx->priv_ctx_tx;
2625         }
2626
2627         crypto_init_wait(&sw_ctx_tx->async_wait);
2628         atomic_set(&sw_ctx_tx->encrypt_pending, 1);
2629         INIT_LIST_HEAD(&sw_ctx_tx->tx_list);
2630         INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler);
2631         sw_ctx_tx->tx_work.sk = sk;
2632
2633         return sw_ctx_tx;
2634 }
2635
2636 static struct tls_sw_context_rx *init_ctx_rx(struct tls_context *ctx)
2637 {
2638         struct tls_sw_context_rx *sw_ctx_rx;
2639
2640         if (!ctx->priv_ctx_rx) {
2641                 sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL);
2642                 if (!sw_ctx_rx)
2643                         return NULL;
2644         } else {
2645                 sw_ctx_rx = ctx->priv_ctx_rx;
2646         }
2647
2648         crypto_init_wait(&sw_ctx_rx->async_wait);
2649         atomic_set(&sw_ctx_rx->decrypt_pending, 1);
2650         init_waitqueue_head(&sw_ctx_rx->wq);
2651         skb_queue_head_init(&sw_ctx_rx->rx_list);
2652         skb_queue_head_init(&sw_ctx_rx->async_hold);
2653
2654         return sw_ctx_rx;
2655 }
2656
2657 int init_prot_info(struct tls_prot_info *prot,
2658                    const struct tls_crypto_info *crypto_info,
2659                    const struct tls_cipher_desc *cipher_desc)
2660 {
2661         u16 nonce_size = cipher_desc->nonce;
2662
2663         if (crypto_info->version == TLS_1_3_VERSION) {
2664                 nonce_size = 0;
2665                 prot->aad_size = TLS_HEADER_SIZE;
2666                 prot->tail_size = 1;
2667         } else {
2668                 prot->aad_size = TLS_AAD_SPACE_SIZE;
2669                 prot->tail_size = 0;
2670         }
2671
2672         /* Sanity-check the sizes for stack allocations. */
2673         if (nonce_size > TLS_MAX_IV_SIZE || prot->aad_size > TLS_MAX_AAD_SIZE)
2674                 return -EINVAL;
2675
2676         prot->version = crypto_info->version;
2677         prot->cipher_type = crypto_info->cipher_type;
2678         prot->prepend_size = TLS_HEADER_SIZE + nonce_size;
2679         prot->tag_size = cipher_desc->tag;
2680         prot->overhead_size = prot->prepend_size + prot->tag_size + prot->tail_size;
2681         prot->iv_size = cipher_desc->iv;
2682         prot->salt_size = cipher_desc->salt;
2683         prot->rec_seq_size = cipher_desc->rec_seq;
2684
2685         return 0;
2686 }
2687
2688 int tls_set_sw_offload(struct sock *sk, int tx)
2689 {
2690         struct tls_sw_context_tx *sw_ctx_tx = NULL;
2691         struct tls_sw_context_rx *sw_ctx_rx = NULL;
2692         const struct tls_cipher_desc *cipher_desc;
2693         struct tls_crypto_info *crypto_info;
2694         char *iv, *rec_seq, *key, *salt;
2695         struct cipher_context *cctx;
2696         struct tls_prot_info *prot;
2697         struct crypto_aead **aead;
2698         struct tls_context *ctx;
2699         struct crypto_tfm *tfm;
2700         int rc = 0;
2701
2702         ctx = tls_get_ctx(sk);
2703         prot = &ctx->prot_info;
2704
2705         if (tx) {
2706                 ctx->priv_ctx_tx = init_ctx_tx(ctx, sk);
2707                 if (!ctx->priv_ctx_tx)
2708                         return -ENOMEM;
2709
2710                 sw_ctx_tx = ctx->priv_ctx_tx;
2711                 crypto_info = &ctx->crypto_send.info;
2712                 cctx = &ctx->tx;
2713                 aead = &sw_ctx_tx->aead_send;
2714         } else {
2715                 ctx->priv_ctx_rx = init_ctx_rx(ctx);
2716                 if (!ctx->priv_ctx_rx)
2717                         return -ENOMEM;
2718
2719                 sw_ctx_rx = ctx->priv_ctx_rx;
2720                 crypto_info = &ctx->crypto_recv.info;
2721                 cctx = &ctx->rx;
2722                 aead = &sw_ctx_rx->aead_recv;
2723         }
2724
2725         cipher_desc = get_cipher_desc(crypto_info->cipher_type);
2726         if (!cipher_desc) {
2727                 rc = -EINVAL;
2728                 goto free_priv;
2729         }
2730
2731         rc = init_prot_info(prot, crypto_info, cipher_desc);
2732         if (rc)
2733                 goto free_priv;
2734
2735         iv = crypto_info_iv(crypto_info, cipher_desc);
2736         key = crypto_info_key(crypto_info, cipher_desc);
2737         salt = crypto_info_salt(crypto_info, cipher_desc);
2738         rec_seq = crypto_info_rec_seq(crypto_info, cipher_desc);
2739
2740         memcpy(cctx->iv, salt, cipher_desc->salt);
2741         memcpy(cctx->iv + cipher_desc->salt, iv, cipher_desc->iv);
2742         memcpy(cctx->rec_seq, rec_seq, cipher_desc->rec_seq);
2743
2744         if (!*aead) {
2745                 *aead = crypto_alloc_aead(cipher_desc->cipher_name, 0, 0);
2746                 if (IS_ERR(*aead)) {
2747                         rc = PTR_ERR(*aead);
2748                         *aead = NULL;
2749                         goto free_priv;
2750                 }
2751         }
2752
2753         ctx->push_pending_record = tls_sw_push_pending_record;
2754
2755         rc = crypto_aead_setkey(*aead, key, cipher_desc->key);
2756         if (rc)
2757                 goto free_aead;
2758
2759         rc = crypto_aead_setauthsize(*aead, prot->tag_size);
2760         if (rc)
2761                 goto free_aead;
2762
2763         if (sw_ctx_rx) {
2764                 tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv);
2765
2766                 tls_update_rx_zc_capable(ctx);
2767                 sw_ctx_rx->async_capable =
2768                         crypto_info->version != TLS_1_3_VERSION &&
2769                         !!(tfm->__crt_alg->cra_flags & CRYPTO_ALG_ASYNC);
2770
2771                 rc = tls_strp_init(&sw_ctx_rx->strp, sk);
2772                 if (rc)
2773                         goto free_aead;
2774         }
2775
2776         goto out;
2777
2778 free_aead:
2779         crypto_free_aead(*aead);
2780         *aead = NULL;
2781 free_priv:
2782         if (tx) {
2783                 kfree(ctx->priv_ctx_tx);
2784                 ctx->priv_ctx_tx = NULL;
2785         } else {
2786                 kfree(ctx->priv_ctx_rx);
2787                 ctx->priv_ctx_rx = NULL;
2788         }
2789 out:
2790         return rc;
2791 }