fs/cifs/smb2transport.c

   1 /*
   2  *   fs/cifs/smb2transport.c
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2002, 2011
   5  *                 Etersoft, 2012
   6  *   Author(s): Steve French (sfrench@us.ibm.com)
   7  *              Jeremy Allison (jra@samba.org) 2006
   8  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
   9  *
  10  *   This library is free software; you can redistribute it and/or modify
  11  *   it under the terms of the GNU Lesser General Public License as published
  12  *   by the Free Software Foundation; either version 2.1 of the License, or
  13  *   (at your option) any later version.
  14  *
  15  *   This library is distributed in the hope that it will be useful,
  16  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  18  *   the GNU Lesser General Public License for more details.
  19  *
  20  *   You should have received a copy of the GNU Lesser General Public License
  21  *   along with this library; if not, write to the Free Software
  22  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23  */
  24
  25 #include <linux/fs.h>
  26 #include <linux/list.h>
  27 #include <linux/wait.h>
  28 #include <linux/net.h>
  29 #include <linux/delay.h>
  30 #include <linux/uaccess.h>
  31 #include <asm/processor.h>
  32 #include <linux/mempool.h>
  33 #include <linux/highmem.h>
  34 #include <crypto/aead.h>
  35 #include "smb2pdu.h"
  36 #include "cifsglob.h"
  37 #include "cifsproto.h"
  38 #include "smb2proto.h"
  39 #include "cifs_debug.h"
  40 #include "smb2status.h"
  41 #include "smb2glob.h"
  42
  43 static int
  44 smb2_crypto_shash_allocate(struct TCP_Server_Info *server)
  45 {
  46         return cifs_alloc_hash("hmac(sha256)",
  47                                &server->secmech.hmacsha256,
  48                                &server->secmech.sdeschmacsha256);
  49 }
  50
  51 static int
  52 smb3_crypto_shash_allocate(struct TCP_Server_Info *server)
  53 {
  54         struct cifs_secmech *p = &server->secmech;
  55         int rc;
  56
  57         rc = cifs_alloc_hash("hmac(sha256)",
  58                              &p->hmacsha256,
  59                              &p->sdeschmacsha256);
  60         if (rc)
  61                 goto err;
  62
  63         rc = cifs_alloc_hash("cmac(aes)", &p->cmacaes, &p->sdesccmacaes);
  64         if (rc)
  65                 goto err;
  66
  67         return 0;
  68 err:
  69         cifs_free_hash(&p->hmacsha256, &p->sdeschmacsha256);
  70         return rc;
  71 }
  72
  73 #ifdef CONFIG_CIFS_SMB311
  74 int
  75 smb311_crypto_shash_allocate(struct TCP_Server_Info *server)
  76 {
  77         struct cifs_secmech *p = &server->secmech;
  78         int rc = 0;
  79
  80         rc = cifs_alloc_hash("hmac(sha256)",
  81                              &p->hmacsha256,
  82                              &p->sdeschmacsha256);
  83         if (rc)
  84                 return rc;
  85
  86         rc = cifs_alloc_hash("cmac(aes)", &p->cmacaes, &p->sdesccmacaes);
  87         if (rc)
  88                 goto err;
  89
  90         rc = cifs_alloc_hash("sha512", &p->sha512, &p->sdescsha512);
  91         if (rc)
  92                 goto err;
  93
  94         return 0;
  95
  96 err:
  97         cifs_free_hash(&p->cmacaes, &p->sdesccmacaes);
  98         cifs_free_hash(&p->hmacsha256, &p->sdeschmacsha256);
  99         return rc;
 100 }
 101 #endif
 102
 103 static struct cifs_ses *
 104 smb2_find_smb_ses_unlocked(struct TCP_Server_Info *server, __u64 ses_id)
 105 {
 106         struct cifs_ses *ses;
 107
 108         list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
 109                 if (ses->Suid != ses_id)
 110                         continue;
 111                 return ses;
 112         }
 113
 114         return NULL;
 115 }
 116
 117 struct cifs_ses *
 118 smb2_find_smb_ses(struct TCP_Server_Info *server, __u64 ses_id)
 119 {
 120         struct cifs_ses *ses;
 121
 122         spin_lock(&cifs_tcp_ses_lock);
 123         ses = smb2_find_smb_ses_unlocked(server, ses_id);
 124         spin_unlock(&cifs_tcp_ses_lock);
 125
 126         return ses;
 127 }
 128
 129 static struct cifs_tcon *
 130 smb2_find_smb_sess_tcon_unlocked(struct cifs_ses *ses, __u32  tid)
 131 {
 132         struct cifs_tcon *tcon;
 133
 134         list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 135                 if (tcon->tid != tid)
 136                         continue;
 137                 ++tcon->tc_count;
 138                 return tcon;
 139         }
 140
 141         return NULL;
 142 }
 143
 144 /*
 145  * Obtain tcon corresponding to the tid in the given
 146  * cifs_ses
 147  */
 148
 149 struct cifs_tcon *
 150 smb2_find_smb_tcon(struct TCP_Server_Info *server, __u64 ses_id, __u32  tid)
 151 {
 152         struct cifs_ses *ses;
 153         struct cifs_tcon *tcon;
 154
 155         spin_lock(&cifs_tcp_ses_lock);
 156         ses = smb2_find_smb_ses_unlocked(server, ses_id);
 157         if (!ses) {
 158                 spin_unlock(&cifs_tcp_ses_lock);
 159                 return NULL;
 160         }
 161         tcon = smb2_find_smb_sess_tcon_unlocked(ses, tid);
 162         spin_unlock(&cifs_tcp_ses_lock);
 163
 164         return tcon;
 165 }
 166
 167 int
 168 smb2_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
 169 {
 170         int rc;
 171         unsigned char smb2_signature[SMB2_HMACSHA256_SIZE];
 172         unsigned char *sigptr = smb2_signature;
 173         struct kvec *iov = rqst->rq_iov;
 174         int iov_hdr_index = rqst->rq_nvec > 1 ? 1 : 0;
 175         struct smb2_sync_hdr *shdr =
 176                 (struct smb2_sync_hdr *)iov[iov_hdr_index].iov_base;
 177         struct cifs_ses *ses;
 178
 179         ses = smb2_find_smb_ses(server, shdr->SessionId);
 180         if (!ses) {
 181                 cifs_dbg(VFS, "%s: Could not find session\n", __func__);
 182                 return 0;
 183         }
 184
 185         memset(smb2_signature, 0x0, SMB2_HMACSHA256_SIZE);
 186         memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
 187
 188         rc = smb2_crypto_shash_allocate(server);
 189         if (rc) {
 190                 cifs_dbg(VFS, "%s: shah256 alloc failed\n", __func__);
 191                 return rc;
 192         }
 193
 194         rc = crypto_shash_setkey(server->secmech.hmacsha256,
 195                 ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
 196         if (rc) {
 197                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 198                 return rc;
 199         }
 200
 201         rc = crypto_shash_init(&server->secmech.sdeschmacsha256->shash);
 202         if (rc) {
 203                 cifs_dbg(VFS, "%s: Could not init sha256", __func__);
 204                 return rc;
 205         }
 206
 207         rc = __cifs_calc_signature(rqst, iov_hdr_index,  server, sigptr,
 208                 &server->secmech.sdeschmacsha256->shash);
 209
 210         if (!rc)
 211                 memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
 212
 213         return rc;
 214 }
 215
 216 static int generate_key(struct cifs_ses *ses, struct kvec label,
 217                         struct kvec context, __u8 *key, unsigned int key_size)
 218 {
 219         unsigned char zero = 0x0;
 220         __u8 i[4] = {0, 0, 0, 1};
 221         __u8 L[4] = {0, 0, 0, 128};
 222         int rc = 0;
 223         unsigned char prfhash[SMB2_HMACSHA256_SIZE];
 224         unsigned char *hashptr = prfhash;
 225
 226         memset(prfhash, 0x0, SMB2_HMACSHA256_SIZE);
 227         memset(key, 0x0, key_size);
 228
 229         rc = smb3_crypto_shash_allocate(ses->server);
 230         if (rc) {
 231                 cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
 232                 goto smb3signkey_ret;
 233         }
 234
 235         rc = crypto_shash_setkey(ses->server->secmech.hmacsha256,
 236                 ses->auth_key.response, SMB2_NTLMV2_SESSKEY_SIZE);
 237         if (rc) {
 238                 cifs_dbg(VFS, "%s: Could not set with session key\n", __func__);
 239                 goto smb3signkey_ret;
 240         }
 241
 242         rc = crypto_shash_init(&ses->server->secmech.sdeschmacsha256->shash);
 243         if (rc) {
 244                 cifs_dbg(VFS, "%s: Could not init sign hmac\n", __func__);
 245                 goto smb3signkey_ret;
 246         }
 247
 248         rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
 249                                 i, 4);
 250         if (rc) {
 251                 cifs_dbg(VFS, "%s: Could not update with n\n", __func__);
 252                 goto smb3signkey_ret;
 253         }
 254
 255         rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
 256                                 label.iov_base, label.iov_len);
 257         if (rc) {
 258                 cifs_dbg(VFS, "%s: Could not update with label\n", __func__);
 259                 goto smb3signkey_ret;
 260         }
 261
 262         rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
 263                                 &zero, 1);
 264         if (rc) {
 265                 cifs_dbg(VFS, "%s: Could not update with zero\n", __func__);
 266                 goto smb3signkey_ret;
 267         }
 268
 269         rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
 270                                 context.iov_base, context.iov_len);
 271         if (rc) {
 272                 cifs_dbg(VFS, "%s: Could not update with context\n", __func__);
 273                 goto smb3signkey_ret;
 274         }
 275
 276         rc = crypto_shash_update(&ses->server->secmech.sdeschmacsha256->shash,
 277                                 L, 4);
 278         if (rc) {
 279                 cifs_dbg(VFS, "%s: Could not update with L\n", __func__);
 280                 goto smb3signkey_ret;
 281         }
 282
 283         rc = crypto_shash_final(&ses->server->secmech.sdeschmacsha256->shash,
 284                                 hashptr);
 285         if (rc) {
 286                 cifs_dbg(VFS, "%s: Could not generate sha256 hash\n", __func__);
 287                 goto smb3signkey_ret;
 288         }
 289
 290         memcpy(key, hashptr, key_size);
 291
 292 smb3signkey_ret:
 293         return rc;
 294 }
 295
 296 struct derivation {
 297         struct kvec label;
 298         struct kvec context;
 299 };
 300
 301 struct derivation_triplet {
 302         struct derivation signing;
 303         struct derivation encryption;
 304         struct derivation decryption;
 305 };
 306
 307 static int
 308 generate_smb3signingkey(struct cifs_ses *ses,
 309                         const struct derivation_triplet *ptriplet)
 310 {
 311         int rc;
 312
 313         rc = generate_key(ses, ptriplet->signing.label,
 314                           ptriplet->signing.context, ses->smb3signingkey,
 315                           SMB3_SIGN_KEY_SIZE);
 316         if (rc)
 317                 return rc;
 318
 319         rc = generate_key(ses, ptriplet->encryption.label,
 320                           ptriplet->encryption.context, ses->smb3encryptionkey,
 321                           SMB3_SIGN_KEY_SIZE);
 322         if (rc)
 323                 return rc;
 324
 325         rc = generate_key(ses, ptriplet->decryption.label,
 326                           ptriplet->decryption.context,
 327                           ses->smb3decryptionkey, SMB3_SIGN_KEY_SIZE);
 328
 329         if (rc)
 330                 return rc;
 331
 332 #ifdef CONFIG_CIFS_DEBUG_DUMP_KEYS
 333         cifs_dbg(VFS, "%s: dumping generated AES session keys\n", __func__);
 334         /*
 335          * The session id is opaque in terms of endianness, so we can't
 336          * print it as a long long. we dump it as we got it on the wire
 337          */
 338         cifs_dbg(VFS, "Session Id    %*ph\n", (int)sizeof(ses->Suid),
 339                         &ses->Suid);
 340         cifs_dbg(VFS, "Session Key   %*ph\n",
 341                  SMB2_NTLMV2_SESSKEY_SIZE, ses->auth_key.response);
 342         cifs_dbg(VFS, "Signing Key   %*ph\n",
 343                  SMB3_SIGN_KEY_SIZE, ses->smb3signingkey);
 344         cifs_dbg(VFS, "ServerIn Key  %*ph\n",
 345                  SMB3_SIGN_KEY_SIZE, ses->smb3encryptionkey);
 346         cifs_dbg(VFS, "ServerOut Key %*ph\n",
 347                  SMB3_SIGN_KEY_SIZE, ses->smb3decryptionkey);
 348 #endif
 349         return rc;
 350 }
 351
 352 int
 353 generate_smb30signingkey(struct cifs_ses *ses)
 354
 355 {
 356         struct derivation_triplet triplet;
 357         struct derivation *d;
 358
 359         d = &triplet.signing;
 360         d->label.iov_base = "SMB2AESCMAC";
 361         d->label.iov_len = 12;
 362         d->context.iov_base = "SmbSign";
 363         d->context.iov_len = 8;
 364
 365         d = &triplet.encryption;
 366         d->label.iov_base = "SMB2AESCCM";
 367         d->label.iov_len = 11;
 368         d->context.iov_base = "ServerIn ";
 369         d->context.iov_len = 10;
 370
 371         d = &triplet.decryption;
 372         d->label.iov_base = "SMB2AESCCM";
 373         d->label.iov_len = 11;
 374         d->context.iov_base = "ServerOut";
 375         d->context.iov_len = 10;
 376
 377         return generate_smb3signingkey(ses, &triplet);
 378 }
 379
 380 #ifdef CONFIG_CIFS_SMB311
 381 int
 382 generate_smb311signingkey(struct cifs_ses *ses)
 383
 384 {
 385         struct derivation_triplet triplet;
 386         struct derivation *d;
 387
 388         d = &triplet.signing;
 389         d->label.iov_base = "SMBSigningKey";
 390         d->label.iov_len = 14;
 391         d->context.iov_base = ses->preauth_sha_hash;
 392         d->context.iov_len = 64;
 393
 394         d = &triplet.encryption;
 395         d->label.iov_base = "SMBC2SCipherKey";
 396         d->label.iov_len = 16;
 397         d->context.iov_base = ses->preauth_sha_hash;
 398         d->context.iov_len = 64;
 399
 400         d = &triplet.decryption;
 401         d->label.iov_base = "SMBS2CCipherKey";
 402         d->label.iov_len = 16;
 403         d->context.iov_base = ses->preauth_sha_hash;
 404         d->context.iov_len = 64;
 405
 406         return generate_smb3signingkey(ses, &triplet);
 407 }
 408 #endif /* 311 */
 409
 410 int
 411 smb3_calc_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
 412 {
 413         int rc = 0;
 414         unsigned char smb3_signature[SMB2_CMACAES_SIZE];
 415         unsigned char *sigptr = smb3_signature;
 416         struct kvec *iov = rqst->rq_iov;
 417         int iov_hdr_index = rqst->rq_nvec > 1 ? 1 : 0;
 418         struct smb2_sync_hdr *shdr =
 419                 (struct smb2_sync_hdr *)iov[iov_hdr_index].iov_base;
 420         struct cifs_ses *ses;
 421
 422         ses = smb2_find_smb_ses(server, shdr->SessionId);
 423         if (!ses) {
 424                 cifs_dbg(VFS, "%s: Could not find session\n", __func__);
 425                 return 0;
 426         }
 427
 428         memset(smb3_signature, 0x0, SMB2_CMACAES_SIZE);
 429         memset(shdr->Signature, 0x0, SMB2_SIGNATURE_SIZE);
 430
 431         rc = crypto_shash_setkey(server->secmech.cmacaes,
 432                 ses->smb3signingkey, SMB2_CMACAES_SIZE);
 433
 434         if (rc) {
 435                 cifs_dbg(VFS, "%s: Could not set key for cmac aes\n", __func__);
 436                 return rc;
 437         }
 438
 439         /*
 440          * we already allocate sdesccmacaes when we init smb3 signing key,
 441          * so unlike smb2 case we do not have to check here if secmech are
 442          * initialized
 443          */
 444         rc = crypto_shash_init(&server->secmech.sdesccmacaes->shash);
 445         if (rc) {
 446                 cifs_dbg(VFS, "%s: Could not init cmac aes\n", __func__);
 447                 return rc;
 448         }
 449
 450         rc = __cifs_calc_signature(rqst, iov_hdr_index, server, sigptr,
 451                                    &server->secmech.sdesccmacaes->shash);
 452
 453         if (!rc)
 454                 memcpy(shdr->Signature, sigptr, SMB2_SIGNATURE_SIZE);
 455
 456         return rc;
 457 }
 458
 459 /* must be called with server->srv_mutex held */
 460 static int
 461 smb2_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server)
 462 {
 463         int rc = 0;
 464         struct smb2_sync_hdr *shdr =
 465                         (struct smb2_sync_hdr *)rqst->rq_iov[1].iov_base;
 466
 467         if (!(shdr->Flags & SMB2_FLAGS_SIGNED) ||
 468             server->tcpStatus == CifsNeedNegotiate)
 469                 return rc;
 470
 471         if (!server->session_estab) {
 472                 strncpy(shdr->Signature, "BSRSPYL", 8);
 473                 return rc;
 474         }
 475
 476         rc = server->ops->calc_signature(rqst, server);
 477
 478         return rc;
 479 }
 480
 481 int
 482 smb2_verify_signature(struct smb_rqst *rqst, struct TCP_Server_Info *server)
 483 {
 484         unsigned int rc;
 485         char server_response_sig[16];
 486         struct smb2_sync_hdr *shdr =
 487                         (struct smb2_sync_hdr *)rqst->rq_iov[0].iov_base;
 488
 489         if ((shdr->Command == SMB2_NEGOTIATE) ||
 490             (shdr->Command == SMB2_SESSION_SETUP) ||
 491             (shdr->Command == SMB2_OPLOCK_BREAK) ||
 492             (!server->session_estab))
 493                 return 0;
 494
 495         /*
 496          * BB what if signatures are supposed to be on for session but
 497          * server does not send one? BB
 498          */
 499
 500         /* Do not need to verify session setups with signature "BSRSPYL " */
 501         if (memcmp(shdr->Signature, "BSRSPYL ", 8) == 0)
 502                 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
 503                          shdr->Command);
 504
 505         /*
 506          * Save off the origiginal signature so we can modify the smb and check
 507          * our calculated signature against what the server sent.
 508          */
 509         memcpy(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE);
 510
 511         memset(shdr->Signature, 0, SMB2_SIGNATURE_SIZE);
 512
 513         mutex_lock(&server->srv_mutex);
 514         rc = server->ops->calc_signature(rqst, server);
 515         mutex_unlock(&server->srv_mutex);
 516
 517         if (rc)
 518                 return rc;
 519
 520         if (memcmp(server_response_sig, shdr->Signature, SMB2_SIGNATURE_SIZE))
 521                 return -EACCES;
 522         else
 523                 return 0;
 524 }
 525
 526 /*
 527  * Set message id for the request. Should be called after wait_for_free_request
 528  * and when srv_mutex is held.
 529  */
 530 static inline void
 531 smb2_seq_num_into_buf(struct TCP_Server_Info *server,
 532                       struct smb2_sync_hdr *shdr)
 533 {
 534         unsigned int i, num = le16_to_cpu(shdr->CreditCharge);
 535
 536         shdr->MessageId = get_next_mid64(server);
 537         /* skip message numbers according to CreditCharge field */
 538         for (i = 1; i < num; i++)
 539                 get_next_mid(server);
 540 }
 541
 542 static struct mid_q_entry *
 543 smb2_mid_entry_alloc(const struct smb2_sync_hdr *shdr,
 544                      struct TCP_Server_Info *server)
 545 {
 546         struct mid_q_entry *temp;
 547
 548         if (server == NULL) {
 549                 cifs_dbg(VFS, "Null TCP session in smb2_mid_entry_alloc\n");
 550                 return NULL;
 551         }
 552
 553         temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
 554         memset(temp, 0, sizeof(struct mid_q_entry));
 555         temp->mid = le64_to_cpu(shdr->MessageId);
 556         temp->pid = current->pid;
 557         temp->command = shdr->Command; /* Always LE */
 558         temp->when_alloc = jiffies;
 559         temp->server = server;
 560
 561         /*
 562          * The default is for the mid to be synchronous, so the
 563          * default callback just wakes up the current task.
 564          */
 565         temp->callback = cifs_wake_up_task;
 566         temp->callback_data = current;
 567
 568         atomic_inc(&midCount);
 569         temp->mid_state = MID_REQUEST_ALLOCATED;
 570         return temp;
 571 }
 572
 573 static int
 574 smb2_get_mid_entry(struct cifs_ses *ses, struct smb2_sync_hdr *shdr,
 575                    struct mid_q_entry **mid)
 576 {
 577         if (ses->server->tcpStatus == CifsExiting)
 578                 return -ENOENT;
 579
 580         if (ses->server->tcpStatus == CifsNeedReconnect) {
 581                 cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
 582                 return -EAGAIN;
 583         }
 584
 585         if (ses->status == CifsNew) {
 586                 if ((shdr->Command != SMB2_SESSION_SETUP) &&
 587                     (shdr->Command != SMB2_NEGOTIATE))
 588                         return -EAGAIN;
 589                 /* else ok - we are setting up session */
 590         }
 591
 592         if (ses->status == CifsExiting) {
 593                 if (shdr->Command != SMB2_LOGOFF)
 594                         return -EAGAIN;
 595                 /* else ok - we are shutting down the session */
 596         }
 597
 598         *mid = smb2_mid_entry_alloc(shdr, ses->server);
 599         if (*mid == NULL)
 600                 return -ENOMEM;
 601         spin_lock(&GlobalMid_Lock);
 602         list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q);
 603         spin_unlock(&GlobalMid_Lock);
 604         return 0;
 605 }
 606
 607 int
 608 smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 609                    bool log_error)
 610 {
 611         unsigned int len = mid->resp_buf_size;
 612         struct kvec iov[1];
 613         struct smb_rqst rqst = { .rq_iov = iov,
 614                                  .rq_nvec = 1 };
 615
 616         iov[0].iov_base = (char *)mid->resp_buf;
 617         iov[0].iov_len = len;
 618
 619         dump_smb(mid->resp_buf, min_t(u32, 80, len));
 620         /* convert the length into a more usable form */
 621         if (len > 24 && server->sign && !mid->decrypted) {
 622                 int rc;
 623
 624                 rc = smb2_verify_signature(&rqst, server);
 625                 if (rc)
 626                         cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
 627                                  rc);
 628         }
 629
 630         return map_smb2_to_linux_error(mid->resp_buf, log_error);
 631 }
 632
 633 struct mid_q_entry *
 634 smb2_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
 635 {
 636         int rc;
 637         struct smb2_sync_hdr *shdr =
 638                         (struct smb2_sync_hdr *)rqst->rq_iov[1].iov_base;
 639         struct mid_q_entry *mid;
 640
 641         smb2_seq_num_into_buf(ses->server, shdr);
 642
 643         rc = smb2_get_mid_entry(ses, shdr, &mid);
 644         if (rc)
 645                 return ERR_PTR(rc);
 646         rc = smb2_sign_rqst(rqst, ses->server);
 647         if (rc) {
 648                 cifs_delete_mid(mid);
 649                 return ERR_PTR(rc);
 650         }
 651         return mid;
 652 }
 653
 654 struct mid_q_entry *
 655 smb2_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
 656 {
 657         int rc;
 658         struct smb2_sync_hdr *shdr =
 659                         (struct smb2_sync_hdr *)rqst->rq_iov[1].iov_base;
 660         struct mid_q_entry *mid;
 661
 662         smb2_seq_num_into_buf(server, shdr);
 663
 664         mid = smb2_mid_entry_alloc(shdr, server);
 665         if (mid == NULL)
 666                 return ERR_PTR(-ENOMEM);
 667
 668         rc = smb2_sign_rqst(rqst, server);
 669         if (rc) {
 670                 DeleteMidQEntry(mid);
 671                 return ERR_PTR(rc);
 672         }
 673
 674         return mid;
 675 }
 676
 677 int
 678 smb3_crypto_aead_allocate(struct TCP_Server_Info *server)
 679 {
 680         struct crypto_aead *tfm;
 681
 682         if (!server->secmech.ccmaesencrypt) {
 683                 tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
 684                 if (IS_ERR(tfm)) {
 685                         cifs_dbg(VFS, "%s: Failed to alloc encrypt aead\n",
 686                                  __func__);
 687                         return PTR_ERR(tfm);
 688                 }
 689                 server->secmech.ccmaesencrypt = tfm;
 690         }
 691
 692         if (!server->secmech.ccmaesdecrypt) {
 693                 tfm = crypto_alloc_aead("ccm(aes)", 0, 0);
 694                 if (IS_ERR(tfm)) {
 695                         crypto_free_aead(server->secmech.ccmaesencrypt);
 696                         server->secmech.ccmaesencrypt = NULL;
 697                         cifs_dbg(VFS, "%s: Failed to alloc decrypt aead\n",
 698                                  __func__);
 699                         return PTR_ERR(tfm);
 700                 }
 701                 server->secmech.ccmaesdecrypt = tfm;
 702         }
 703
 704         return 0;
 705 }