crypto/algif_aead.c

   1 /*
   2  * algif_aead: User-space interface for AEAD algorithms
   3  *
   4  * Copyright (C) 2014, Stephan Mueller <smueller@chronox.de>
   5  *
   6  * This file provides the user-space API for AEAD ciphers.
   7  *
   8  * This file is derived from algif_skcipher.c.
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 2 of the License, or (at your option)
  13  * any later version.
  14  */
  15
  16 #include <crypto/internal/aead.h>
  17 #include <crypto/scatterwalk.h>
  18 #include <crypto/if_alg.h>
  19 #include <linux/init.h>
  20 #include <linux/list.h>
  21 #include <linux/kernel.h>
  22 #include <linux/mm.h>
  23 #include <linux/module.h>
  24 #include <linux/net.h>
  25 #include <net/sock.h>
  26
  27 struct aead_sg_list {
  28         unsigned int cur;
  29         struct scatterlist sg[ALG_MAX_PAGES];
  30 };
  31
  32 struct aead_async_rsgl {
  33         struct af_alg_sgl sgl;
  34         struct list_head list;
  35 };
  36
  37 struct aead_async_req {
  38         struct scatterlist *tsgl;
  39         struct aead_async_rsgl first_rsgl;
  40         struct list_head list;
  41         struct kiocb *iocb;
  42         unsigned int tsgls;
  43         char iv[];
  44 };
  45
  46 struct aead_ctx {
  47         struct aead_sg_list tsgl;
  48         struct aead_async_rsgl first_rsgl;
  49         struct list_head list;
  50
  51         void *iv;
  52
  53         struct af_alg_completion completion;
  54
  55         unsigned long used;
  56
  57         unsigned int len;
  58         bool more;
  59         bool merge;
  60         bool enc;
  61
  62         size_t aead_assoclen;
  63         struct aead_request aead_req;
  64 };
  65
  66 static inline int aead_sndbuf(struct sock *sk)
  67 {
  68         struct alg_sock *ask = alg_sk(sk);
  69         struct aead_ctx *ctx = ask->private;
  70
  71         return max_t(int, max_t(int, sk->sk_sndbuf & PAGE_MASK, PAGE_SIZE) -
  72                           ctx->used, 0);
  73 }
  74
  75 static inline bool aead_writable(struct sock *sk)
  76 {
  77         return PAGE_SIZE <= aead_sndbuf(sk);
  78 }
  79
  80 static inline bool aead_sufficient_data(struct aead_ctx *ctx)
  81 {
  82         unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req));
  83
  84         return ctx->used >= ctx->aead_assoclen + as;
  85 }
  86
  87 static void aead_reset_ctx(struct aead_ctx *ctx)
  88 {
  89         struct aead_sg_list *sgl = &ctx->tsgl;
  90
  91         sg_init_table(sgl->sg, ALG_MAX_PAGES);
  92         sgl->cur = 0;
  93         ctx->used = 0;
  94         ctx->more = 0;
  95         ctx->merge = 0;
  96 }
  97
  98 static void aead_put_sgl(struct sock *sk)
  99 {
 100         struct alg_sock *ask = alg_sk(sk);
 101         struct aead_ctx *ctx = ask->private;
 102         struct aead_sg_list *sgl = &ctx->tsgl;
 103         struct scatterlist *sg = sgl->sg;
 104         unsigned int i;
 105
 106         for (i = 0; i < sgl->cur; i++) {
 107                 if (!sg_page(sg + i))
 108                         continue;
 109
 110                 put_page(sg_page(sg + i));
 111                 sg_assign_page(sg + i, NULL);
 112         }
 113         aead_reset_ctx(ctx);
 114 }
 115
 116 static void aead_wmem_wakeup(struct sock *sk)
 117 {
 118         struct socket_wq *wq;
 119
 120         if (!aead_writable(sk))
 121                 return;
 122
 123         rcu_read_lock();
 124         wq = rcu_dereference(sk->sk_wq);
 125         if (skwq_has_sleeper(wq))
 126                 wake_up_interruptible_sync_poll(&wq->wait, POLLIN |
 127                                                            POLLRDNORM |
 128                                                            POLLRDBAND);
 129         sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
 130         rcu_read_unlock();
 131 }
 132
 133 static int aead_wait_for_data(struct sock *sk, unsigned flags)
 134 {
 135         DEFINE_WAIT_FUNC(wait, woken_wake_function);
 136         struct alg_sock *ask = alg_sk(sk);
 137         struct aead_ctx *ctx = ask->private;
 138         long timeout;
 139         int err = -ERESTARTSYS;
 140
 141         if (flags & MSG_DONTWAIT)
 142                 return -EAGAIN;
 143
 144         sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
 145         add_wait_queue(sk_sleep(sk), &wait);
 146         for (;;) {
 147                 if (signal_pending(current))
 148                         break;
 149                 timeout = MAX_SCHEDULE_TIMEOUT;
 150                 if (sk_wait_event(sk, &timeout, !ctx->more, &wait)) {
 151                         err = 0;
 152                         break;
 153                 }
 154         }
 155         remove_wait_queue(sk_sleep(sk), &wait);
 156
 157         sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
 158
 159         return err;
 160 }
 161
 162 static void aead_data_wakeup(struct sock *sk)
 163 {
 164         struct alg_sock *ask = alg_sk(sk);
 165         struct aead_ctx *ctx = ask->private;
 166         struct socket_wq *wq;
 167
 168         if (ctx->more)
 169                 return;
 170         if (!ctx->used)
 171                 return;
 172
 173         rcu_read_lock();
 174         wq = rcu_dereference(sk->sk_wq);
 175         if (skwq_has_sleeper(wq))
 176                 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
 177                                                            POLLRDNORM |
 178                                                            POLLRDBAND);
 179         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
 180         rcu_read_unlock();
 181 }
 182
 183 static int aead_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 184 {
 185         struct sock *sk = sock->sk;
 186         struct alg_sock *ask = alg_sk(sk);
 187         struct aead_ctx *ctx = ask->private;
 188         unsigned ivsize =
 189                 crypto_aead_ivsize(crypto_aead_reqtfm(&ctx->aead_req));
 190         struct aead_sg_list *sgl = &ctx->tsgl;
 191         struct af_alg_control con = {};
 192         long copied = 0;
 193         bool enc = 0;
 194         bool init = 0;
 195         int err = -EINVAL;
 196
 197         if (msg->msg_controllen) {
 198                 err = af_alg_cmsg_send(msg, &con);
 199                 if (err)
 200                         return err;
 201
 202                 init = 1;
 203                 switch (con.op) {
 204                 case ALG_OP_ENCRYPT:
 205                         enc = 1;
 206                         break;
 207                 case ALG_OP_DECRYPT:
 208                         enc = 0;
 209                         break;
 210                 default:
 211                         return -EINVAL;
 212                 }
 213
 214                 if (con.iv && con.iv->ivlen != ivsize)
 215                         return -EINVAL;
 216         }
 217
 218         lock_sock(sk);
 219         if (!ctx->more && ctx->used)
 220                 goto unlock;
 221
 222         if (init) {
 223                 ctx->enc = enc;
 224                 if (con.iv)
 225                         memcpy(ctx->iv, con.iv->iv, ivsize);
 226
 227                 ctx->aead_assoclen = con.aead_assoclen;
 228         }
 229
 230         while (size) {
 231                 size_t len = size;
 232                 struct scatterlist *sg = NULL;
 233
 234                 /* use the existing memory in an allocated page */
 235                 if (ctx->merge) {
 236                         sg = sgl->sg + sgl->cur - 1;
 237                         len = min_t(unsigned long, len,
 238                                     PAGE_SIZE - sg->offset - sg->length);
 239                         err = memcpy_from_msg(page_address(sg_page(sg)) +
 240                                               sg->offset + sg->length,
 241                                               msg, len);
 242                         if (err)
 243                                 goto unlock;
 244
 245                         sg->length += len;
 246                         ctx->merge = (sg->offset + sg->length) &
 247                                      (PAGE_SIZE - 1);
 248
 249                         ctx->used += len;
 250                         copied += len;
 251                         size -= len;
 252                         continue;
 253                 }
 254
 255                 if (!aead_writable(sk)) {
 256                         /* user space sent too much data */
 257                         aead_put_sgl(sk);
 258                         err = -EMSGSIZE;
 259                         goto unlock;
 260                 }
 261
 262                 /* allocate a new page */
 263                 len = min_t(unsigned long, size, aead_sndbuf(sk));
 264                 while (len) {
 265                         size_t plen = 0;
 266
 267                         if (sgl->cur >= ALG_MAX_PAGES) {
 268                                 aead_put_sgl(sk);
 269                                 err = -E2BIG;
 270                                 goto unlock;
 271                         }
 272
 273                         sg = sgl->sg + sgl->cur;
 274                         plen = min_t(size_t, len, PAGE_SIZE);
 275
 276                         sg_assign_page(sg, alloc_page(GFP_KERNEL));
 277                         err = -ENOMEM;
 278                         if (!sg_page(sg))
 279                                 goto unlock;
 280
 281                         err = memcpy_from_msg(page_address(sg_page(sg)),
 282                                               msg, plen);
 283                         if (err) {
 284                                 __free_page(sg_page(sg));
 285                                 sg_assign_page(sg, NULL);
 286                                 goto unlock;
 287                         }
 288
 289                         sg->offset = 0;
 290                         sg->length = plen;
 291                         len -= plen;
 292                         ctx->used += plen;
 293                         copied += plen;
 294                         sgl->cur++;
 295                         size -= plen;
 296                         ctx->merge = plen & (PAGE_SIZE - 1);
 297                 }
 298         }
 299
 300         err = 0;
 301
 302         ctx->more = msg->msg_flags & MSG_MORE;
 303         if (!ctx->more && !aead_sufficient_data(ctx)) {
 304                 aead_put_sgl(sk);
 305                 err = -EMSGSIZE;
 306         }
 307
 308 unlock:
 309         aead_data_wakeup(sk);
 310         release_sock(sk);
 311
 312         return err ?: copied;
 313 }
 314
 315 static ssize_t aead_sendpage(struct socket *sock, struct page *page,
 316                              int offset, size_t size, int flags)
 317 {
 318         struct sock *sk = sock->sk;
 319         struct alg_sock *ask = alg_sk(sk);
 320         struct aead_ctx *ctx = ask->private;
 321         struct aead_sg_list *sgl = &ctx->tsgl;
 322         int err = -EINVAL;
 323
 324         if (flags & MSG_SENDPAGE_NOTLAST)
 325                 flags |= MSG_MORE;
 326
 327         if (sgl->cur >= ALG_MAX_PAGES)
 328                 return -E2BIG;
 329
 330         lock_sock(sk);
 331         if (!ctx->more && ctx->used)
 332                 goto unlock;
 333
 334         if (!size)
 335                 goto done;
 336
 337         if (!aead_writable(sk)) {
 338                 /* user space sent too much data */
 339                 aead_put_sgl(sk);
 340                 err = -EMSGSIZE;
 341                 goto unlock;
 342         }
 343
 344         ctx->merge = 0;
 345
 346         get_page(page);
 347         sg_set_page(sgl->sg + sgl->cur, page, size, offset);
 348         sgl->cur++;
 349         ctx->used += size;
 350
 351         err = 0;
 352
 353 done:
 354         ctx->more = flags & MSG_MORE;
 355         if (!ctx->more && !aead_sufficient_data(ctx)) {
 356                 aead_put_sgl(sk);
 357                 err = -EMSGSIZE;
 358         }
 359
 360 unlock:
 361         aead_data_wakeup(sk);
 362         release_sock(sk);
 363
 364         return err ?: size;
 365 }
 366
 367 #define GET_ASYM_REQ(req, tfm) (struct aead_async_req *) \
 368                 ((char *)req + sizeof(struct aead_request) + \
 369                  crypto_aead_reqsize(tfm))
 370
 371  #define GET_REQ_SIZE(tfm) sizeof(struct aead_async_req) + \
 372         crypto_aead_reqsize(tfm) + crypto_aead_ivsize(tfm) + \
 373         sizeof(struct aead_request)
 374
 375 static void aead_async_cb(struct crypto_async_request *_req, int err)
 376 {
 377         struct sock *sk = _req->data;
 378         struct alg_sock *ask = alg_sk(sk);
 379         struct aead_ctx *ctx = ask->private;
 380         struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req);
 381         struct aead_request *req = aead_request_cast(_req);
 382         struct aead_async_req *areq = GET_ASYM_REQ(req, tfm);
 383         struct scatterlist *sg = areq->tsgl;
 384         struct aead_async_rsgl *rsgl;
 385         struct kiocb *iocb = areq->iocb;
 386         unsigned int i, reqlen = GET_REQ_SIZE(tfm);
 387
 388         list_for_each_entry(rsgl, &areq->list, list) {
 389                 af_alg_free_sg(&rsgl->sgl);
 390                 if (rsgl != &areq->first_rsgl)
 391                         sock_kfree_s(sk, rsgl, sizeof(*rsgl));
 392         }
 393
 394         for (i = 0; i < areq->tsgls; i++)
 395                 put_page(sg_page(sg + i));
 396
 397         sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls);
 398         sock_kfree_s(sk, req, reqlen);
 399         __sock_put(sk);
 400         iocb->ki_complete(iocb, err, err);
 401 }
 402
 403 static int aead_recvmsg_async(struct socket *sock, struct msghdr *msg,
 404                               int flags)
 405 {
 406         struct sock *sk = sock->sk;
 407         struct alg_sock *ask = alg_sk(sk);
 408         struct aead_ctx *ctx = ask->private;
 409         struct crypto_aead *tfm = crypto_aead_reqtfm(&ctx->aead_req);
 410         struct aead_async_req *areq;
 411         struct aead_request *req = NULL;
 412         struct aead_sg_list *sgl = &ctx->tsgl;
 413         struct aead_async_rsgl *last_rsgl = NULL, *rsgl;
 414         unsigned int as = crypto_aead_authsize(tfm);
 415         unsigned int i, reqlen = GET_REQ_SIZE(tfm);
 416         int err = -ENOMEM;
 417         unsigned long used;
 418         size_t outlen;
 419         size_t usedpages = 0;
 420
 421         lock_sock(sk);
 422         if (ctx->more) {
 423                 err = aead_wait_for_data(sk, flags);
 424                 if (err)
 425                         goto unlock;
 426         }
 427
 428         used = ctx->used;
 429         outlen = used;
 430
 431         if (!aead_sufficient_data(ctx))
 432                 goto unlock;
 433
 434         req = sock_kmalloc(sk, reqlen, GFP_KERNEL);
 435         if (unlikely(!req))
 436                 goto unlock;
 437
 438         areq = GET_ASYM_REQ(req, tfm);
 439         memset(&areq->first_rsgl, '\0', sizeof(areq->first_rsgl));
 440         INIT_LIST_HEAD(&areq->list);
 441         areq->iocb = msg->msg_iocb;
 442         memcpy(areq->iv, ctx->iv, crypto_aead_ivsize(tfm));
 443         aead_request_set_tfm(req, tfm);
 444         aead_request_set_ad(req, ctx->aead_assoclen);
 445         aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
 446                                   aead_async_cb, sk);
 447         used -= ctx->aead_assoclen + (ctx->enc ? as : 0);
 448
 449         /* take over all tx sgls from ctx */
 450         areq->tsgl = sock_kmalloc(sk, sizeof(*areq->tsgl) * sgl->cur,
 451                                   GFP_KERNEL);
 452         if (unlikely(!areq->tsgl))
 453                 goto free;
 454
 455         sg_init_table(areq->tsgl, sgl->cur);
 456         for (i = 0; i < sgl->cur; i++)
 457                 sg_set_page(&areq->tsgl[i], sg_page(&sgl->sg[i]),
 458                             sgl->sg[i].length, sgl->sg[i].offset);
 459
 460         areq->tsgls = sgl->cur;
 461
 462         /* create rx sgls */
 463         while (iov_iter_count(&msg->msg_iter)) {
 464                 size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter),
 465                                       (outlen - usedpages));
 466
 467                 if (list_empty(&areq->list)) {
 468                         rsgl = &areq->first_rsgl;
 469
 470                 } else {
 471                         rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
 472                         if (unlikely(!rsgl)) {
 473                                 err = -ENOMEM;
 474                                 goto free;
 475                         }
 476                 }
 477                 rsgl->sgl.npages = 0;
 478                 list_add_tail(&rsgl->list, &areq->list);
 479
 480                 /* make one iovec available as scatterlist */
 481                 err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
 482                 if (err < 0)
 483                         goto free;
 484
 485                 usedpages += err;
 486
 487                 /* chain the new scatterlist with previous one */
 488                 if (last_rsgl)
 489                         af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
 490
 491                 last_rsgl = rsgl;
 492
 493                 /* we do not need more iovecs as we have sufficient memory */
 494                 if (outlen <= usedpages)
 495                         break;
 496
 497                 iov_iter_advance(&msg->msg_iter, err);
 498         }
 499         err = -EINVAL;
 500         /* ensure output buffer is sufficiently large */
 501         if (usedpages < outlen)
 502                 goto free;
 503
 504         aead_request_set_crypt(req, areq->tsgl, areq->first_rsgl.sgl.sg, used,
 505                                areq->iv);
 506         err = ctx->enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req);
 507         if (err) {
 508                 if (err == -EINPROGRESS) {
 509                         sock_hold(sk);
 510                         err = -EIOCBQUEUED;
 511                         aead_reset_ctx(ctx);
 512                         goto unlock;
 513                 } else if (err == -EBADMSG) {
 514                         aead_put_sgl(sk);
 515                 }
 516                 goto free;
 517         }
 518         aead_put_sgl(sk);
 519
 520 free:
 521         list_for_each_entry(rsgl, &areq->list, list) {
 522                 af_alg_free_sg(&rsgl->sgl);
 523                 if (rsgl != &areq->first_rsgl)
 524                         sock_kfree_s(sk, rsgl, sizeof(*rsgl));
 525         }
 526         if (areq->tsgl)
 527                 sock_kfree_s(sk, areq->tsgl, sizeof(*areq->tsgl) * areq->tsgls);
 528         if (req)
 529                 sock_kfree_s(sk, req, reqlen);
 530 unlock:
 531         aead_wmem_wakeup(sk);
 532         release_sock(sk);
 533         return err ? err : outlen;
 534 }
 535
 536 static int aead_recvmsg_sync(struct socket *sock, struct msghdr *msg, int flags)
 537 {
 538         struct sock *sk = sock->sk;
 539         struct alg_sock *ask = alg_sk(sk);
 540         struct aead_ctx *ctx = ask->private;
 541         unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req));
 542         struct aead_sg_list *sgl = &ctx->tsgl;
 543         struct aead_async_rsgl *last_rsgl = NULL;
 544         struct aead_async_rsgl *rsgl, *tmp;
 545         int err = -EINVAL;
 546         unsigned long used = 0;
 547         size_t outlen = 0;
 548         size_t usedpages = 0;
 549
 550         lock_sock(sk);
 551
 552         /*
 553          * AEAD memory structure: For encryption, the tag is appended to the
 554          * ciphertext which implies that the memory allocated for the ciphertext
 555          * must be increased by the tag length. For decryption, the tag
 556          * is expected to be concatenated to the ciphertext. The plaintext
 557          * therefore has a memory size of the ciphertext minus the tag length.
 558          *
 559          * The memory structure for cipher operation has the following
 560          * structure:
 561          *      AEAD encryption input:  assoc data || plaintext
 562          *      AEAD encryption output: cipherntext || auth tag
 563          *      AEAD decryption input:  assoc data || ciphertext || auth tag
 564          *      AEAD decryption output: plaintext
 565          */
 566
 567         if (ctx->more) {
 568                 err = aead_wait_for_data(sk, flags);
 569                 if (err)
 570                         goto unlock;
 571         }
 572
 573         used = ctx->used;
 574
 575         /*
 576          * Make sure sufficient data is present -- note, the same check is
 577          * is also present in sendmsg/sendpage. The checks in sendpage/sendmsg
 578          * shall provide an information to the data sender that something is
 579          * wrong, but they are irrelevant to maintain the kernel integrity.
 580          * We need this check here too in case user space decides to not honor
 581          * the error message in sendmsg/sendpage and still call recvmsg. This
 582          * check here protects the kernel integrity.
 583          */
 584         if (!aead_sufficient_data(ctx))
 585                 goto unlock;
 586
 587         outlen = used;
 588
 589         /*
 590          * The cipher operation input data is reduced by the associated data
 591          * length as this data is processed separately later on.
 592          */
 593         used -= ctx->aead_assoclen + (ctx->enc ? as : 0);
 594
 595         /* convert iovecs of output buffers into scatterlists */
 596         while (iov_iter_count(&msg->msg_iter)) {
 597                 size_t seglen = min_t(size_t, iov_iter_count(&msg->msg_iter),
 598                                       (outlen - usedpages));
 599
 600                 if (list_empty(&ctx->list)) {
 601                         rsgl = &ctx->first_rsgl;
 602                 } else {
 603                         rsgl = sock_kmalloc(sk, sizeof(*rsgl), GFP_KERNEL);
 604                         if (unlikely(!rsgl)) {
 605                                 err = -ENOMEM;
 606                                 goto unlock;
 607                         }
 608                 }
 609                 rsgl->sgl.npages = 0;
 610                 list_add_tail(&rsgl->list, &ctx->list);
 611
 612                 /* make one iovec available as scatterlist */
 613                 err = af_alg_make_sg(&rsgl->sgl, &msg->msg_iter, seglen);
 614                 if (err < 0)
 615                         goto unlock;
 616                 usedpages += err;
 617                 /* chain the new scatterlist with previous one */
 618                 if (last_rsgl)
 619                         af_alg_link_sg(&last_rsgl->sgl, &rsgl->sgl);
 620
 621                 last_rsgl = rsgl;
 622
 623                 /* we do not need more iovecs as we have sufficient memory */
 624                 if (outlen <= usedpages)
 625                         break;
 626                 iov_iter_advance(&msg->msg_iter, err);
 627         }
 628
 629         err = -EINVAL;
 630         /* ensure output buffer is sufficiently large */
 631         if (usedpages < outlen)
 632                 goto unlock;
 633
 634         sg_mark_end(sgl->sg + sgl->cur - 1);
 635         aead_request_set_crypt(&ctx->aead_req, sgl->sg, ctx->first_rsgl.sgl.sg,
 636                                used, ctx->iv);
 637         aead_request_set_ad(&ctx->aead_req, ctx->aead_assoclen);
 638
 639         err = af_alg_wait_for_completion(ctx->enc ?
 640                                          crypto_aead_encrypt(&ctx->aead_req) :
 641                                          crypto_aead_decrypt(&ctx->aead_req),
 642                                          &ctx->completion);
 643
 644         if (err) {
 645                 /* EBADMSG implies a valid cipher operation took place */
 646                 if (err == -EBADMSG)
 647                         aead_put_sgl(sk);
 648
 649                 goto unlock;
 650         }
 651
 652         aead_put_sgl(sk);
 653         err = 0;
 654
 655 unlock:
 656         list_for_each_entry_safe(rsgl, tmp, &ctx->list, list) {
 657                 af_alg_free_sg(&rsgl->sgl);
 658                 if (rsgl != &ctx->first_rsgl)
 659                         sock_kfree_s(sk, rsgl, sizeof(*rsgl));
 660                 list_del(&rsgl->list);
 661         }
 662         INIT_LIST_HEAD(&ctx->list);
 663         aead_wmem_wakeup(sk);
 664         release_sock(sk);
 665
 666         return err ? err : outlen;
 667 }
 668
 669 static int aead_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored,
 670                         int flags)
 671 {
 672         return (msg->msg_iocb && !is_sync_kiocb(msg->msg_iocb)) ?
 673                 aead_recvmsg_async(sock, msg, flags) :
 674                 aead_recvmsg_sync(sock, msg, flags);
 675 }
 676
 677 static unsigned int aead_poll(struct file *file, struct socket *sock,
 678                               poll_table *wait)
 679 {
 680         struct sock *sk = sock->sk;
 681         struct alg_sock *ask = alg_sk(sk);
 682         struct aead_ctx *ctx = ask->private;
 683         unsigned int mask;
 684
 685         sock_poll_wait(file, sk_sleep(sk), wait);
 686         mask = 0;
 687
 688         if (!ctx->more)
 689                 mask |= POLLIN | POLLRDNORM;
 690
 691         if (aead_writable(sk))
 692                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 693
 694         return mask;
 695 }
 696
 697 static struct proto_ops algif_aead_ops = {
 698         .family         =       PF_ALG,
 699
 700         .connect        =       sock_no_connect,
 701         .socketpair     =       sock_no_socketpair,
 702         .getname        =       sock_no_getname,
 703         .ioctl          =       sock_no_ioctl,
 704         .listen         =       sock_no_listen,
 705         .shutdown       =       sock_no_shutdown,
 706         .getsockopt     =       sock_no_getsockopt,
 707         .mmap           =       sock_no_mmap,
 708         .bind           =       sock_no_bind,
 709         .accept         =       sock_no_accept,
 710         .setsockopt     =       sock_no_setsockopt,
 711
 712         .release        =       af_alg_release,
 713         .sendmsg        =       aead_sendmsg,
 714         .sendpage       =       aead_sendpage,
 715         .recvmsg        =       aead_recvmsg,
 716         .poll           =       aead_poll,
 717 };
 718
 719 static void *aead_bind(const char *name, u32 type, u32 mask)
 720 {
 721         return crypto_alloc_aead(name, type, mask);
 722 }
 723
 724 static void aead_release(void *private)
 725 {
 726         crypto_free_aead(private);
 727 }
 728
 729 static int aead_setauthsize(void *private, unsigned int authsize)
 730 {
 731         return crypto_aead_setauthsize(private, authsize);
 732 }
 733
 734 static int aead_setkey(void *private, const u8 *key, unsigned int keylen)
 735 {
 736         return crypto_aead_setkey(private, key, keylen);
 737 }
 738
 739 static void aead_sock_destruct(struct sock *sk)
 740 {
 741         struct alg_sock *ask = alg_sk(sk);
 742         struct aead_ctx *ctx = ask->private;
 743         unsigned int ivlen = crypto_aead_ivsize(
 744                                 crypto_aead_reqtfm(&ctx->aead_req));
 745
 746         WARN_ON(atomic_read(&sk->sk_refcnt) != 0);
 747         aead_put_sgl(sk);
 748         sock_kzfree_s(sk, ctx->iv, ivlen);
 749         sock_kfree_s(sk, ctx, ctx->len);
 750         af_alg_release_parent(sk);
 751 }
 752
 753 static int aead_accept_parent(void *private, struct sock *sk)
 754 {
 755         struct aead_ctx *ctx;
 756         struct alg_sock *ask = alg_sk(sk);
 757         unsigned int len = sizeof(*ctx) + crypto_aead_reqsize(private);
 758         unsigned int ivlen = crypto_aead_ivsize(private);
 759
 760         ctx = sock_kmalloc(sk, len, GFP_KERNEL);
 761         if (!ctx)
 762                 return -ENOMEM;
 763         memset(ctx, 0, len);
 764
 765         ctx->iv = sock_kmalloc(sk, ivlen, GFP_KERNEL);
 766         if (!ctx->iv) {
 767                 sock_kfree_s(sk, ctx, len);
 768                 return -ENOMEM;
 769         }
 770         memset(ctx->iv, 0, ivlen);
 771
 772         ctx->len = len;
 773         ctx->used = 0;
 774         ctx->more = 0;
 775         ctx->merge = 0;
 776         ctx->enc = 0;
 777         ctx->tsgl.cur = 0;
 778         ctx->aead_assoclen = 0;
 779         af_alg_init_completion(&ctx->completion);
 780         sg_init_table(ctx->tsgl.sg, ALG_MAX_PAGES);
 781         INIT_LIST_HEAD(&ctx->list);
 782
 783         ask->private = ctx;
 784
 785         aead_request_set_tfm(&ctx->aead_req, private);
 786         aead_request_set_callback(&ctx->aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
 787                                   af_alg_complete, &ctx->completion);
 788
 789         sk->sk_destruct = aead_sock_destruct;
 790
 791         return 0;
 792 }
 793
 794 static const struct af_alg_type algif_type_aead = {
 795         .bind           =       aead_bind,
 796         .release        =       aead_release,
 797         .setkey         =       aead_setkey,
 798         .setauthsize    =       aead_setauthsize,
 799         .accept         =       aead_accept_parent,
 800         .ops            =       &algif_aead_ops,
 801         .name           =       "aead",
 802         .owner          =       THIS_MODULE
 803 };
 804
 805 static int __init algif_aead_init(void)
 806 {
 807         return af_alg_register_type(&algif_type_aead);
 808 }
 809
 810 static void __exit algif_aead_exit(void)
 811 {
 812         int err = af_alg_unregister_type(&algif_type_aead);
 813         BUG_ON(err);
 814 }
 815
 816 module_init(algif_aead_init);
 817 module_exit(algif_aead_exit);
 818 MODULE_LICENSE("GPL");
 819 MODULE_AUTHOR("Stephan Mueller <smueller@chronox.de>");
 820 MODULE_DESCRIPTION("AEAD kernel crypto API user space interface");