fs/cifs/cifsencrypt.c

   1 /*
   2  *   fs/cifs/cifsencrypt.c
   3  *
   4  *   Encryption and hashing operations relating to NTLM, NTLMv2.  See MS-NLMP
   5  *   for more detailed information
   6  *
   7  *   Copyright (C) International Business Machines  Corp., 2005,2013
   8  *   Author(s): Steve French (sfrench@us.ibm.com)
   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/slab.h>
  27 #include "cifspdu.h"
  28 #include "cifsglob.h"
  29 #include "cifs_debug.h"
  30 #include "cifs_unicode.h"
  31 #include "cifsproto.h"
  32 #include "ntlmssp.h"
  33 #include <linux/ctype.h>
  34 #include <linux/random.h>
  35 #include <linux/highmem.h>
  36 #include <crypto/skcipher.h>
  37 #include <crypto/aead.h>
  38
  39 static int
  40 cifs_crypto_shash_md5_allocate(struct TCP_Server_Info *server)
  41 {
  42         int rc;
  43         unsigned int size;
  44
  45         if (server->secmech.sdescmd5 != NULL)
  46                 return 0; /* already allocated */
  47
  48         server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
  49         if (IS_ERR(server->secmech.md5)) {
  50                 cifs_dbg(VFS, "could not allocate crypto md5\n");
  51                 rc = PTR_ERR(server->secmech.md5);
  52                 server->secmech.md5 = NULL;
  53                 return rc;
  54         }
  55
  56         size = sizeof(struct shash_desc) +
  57                         crypto_shash_descsize(server->secmech.md5);
  58         server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
  59         if (!server->secmech.sdescmd5) {
  60                 crypto_free_shash(server->secmech.md5);
  61                 server->secmech.md5 = NULL;
  62                 return -ENOMEM;
  63         }
  64         server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
  65         server->secmech.sdescmd5->shash.flags = 0x0;
  66
  67         return 0;
  68 }
  69
  70 int __cifs_calc_signature(struct smb_rqst *rqst,
  71                         struct TCP_Server_Info *server, char *signature,
  72                         struct shash_desc *shash)
  73 {
  74         int i;
  75         int rc;
  76         struct kvec *iov = rqst->rq_iov;
  77         int n_vec = rqst->rq_nvec;
  78
  79         if (n_vec < 2 || iov[0].iov_len != 4)
  80                 return -EIO;
  81
  82         for (i = 1; i < n_vec; i++) {
  83                 if (iov[i].iov_len == 0)
  84                         continue;
  85                 if (iov[i].iov_base == NULL) {
  86                         cifs_dbg(VFS, "null iovec entry\n");
  87                         return -EIO;
  88                 }
  89                 if (i == 1 && iov[1].iov_len <= 4)
  90                         break; /* nothing to sign or corrupt header */
  91                 rc = crypto_shash_update(shash,
  92                                          iov[i].iov_base, iov[i].iov_len);
  93                 if (rc) {
  94                         cifs_dbg(VFS, "%s: Could not update with payload\n",
  95                                  __func__);
  96                         return rc;
  97                 }
  98         }
  99
 100         /* now hash over the rq_pages array */
 101         for (i = 0; i < rqst->rq_npages; i++) {
 102                 void *kaddr = kmap(rqst->rq_pages[i]);
 103                 size_t len = rqst->rq_pagesz;
 104
 105                 if (i == rqst->rq_npages - 1)
 106                         len = rqst->rq_tailsz;
 107
 108                 crypto_shash_update(shash, kaddr, len);
 109
 110                 kunmap(rqst->rq_pages[i]);
 111         }
 112
 113         rc = crypto_shash_final(shash, signature);
 114         if (rc)
 115                 cifs_dbg(VFS, "%s: Could not generate hash\n", __func__);
 116
 117         return rc;
 118 }
 119
 120 /*
 121  * Calculate and return the CIFS signature based on the mac key and SMB PDU.
 122  * The 16 byte signature must be allocated by the caller. Note we only use the
 123  * 1st eight bytes and that the smb header signature field on input contains
 124  * the sequence number before this function is called. Also, this function
 125  * should be called with the server->srv_mutex held.
 126  */
 127 static int cifs_calc_signature(struct smb_rqst *rqst,
 128                         struct TCP_Server_Info *server, char *signature)
 129 {
 130         int rc;
 131
 132         if (!rqst->rq_iov || !signature || !server)
 133                 return -EINVAL;
 134
 135         if (!server->secmech.sdescmd5) {
 136                 rc = cifs_crypto_shash_md5_allocate(server);
 137                 if (rc) {
 138                         cifs_dbg(VFS, "%s: Can't alloc md5 crypto\n", __func__);
 139                         return -1;
 140                 }
 141         }
 142
 143         rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
 144         if (rc) {
 145                 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
 146                 return rc;
 147         }
 148
 149         rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
 150                 server->session_key.response, server->session_key.len);
 151         if (rc) {
 152                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 153                 return rc;
 154         }
 155
 156         return __cifs_calc_signature(rqst, server, signature,
 157                                      &server->secmech.sdescmd5->shash);
 158 }
 159
 160 /* must be called with server->srv_mutex held */
 161 int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
 162                    __u32 *pexpected_response_sequence_number)
 163 {
 164         int rc = 0;
 165         char smb_signature[20];
 166         struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
 167
 168         if (rqst->rq_iov[0].iov_len != 4 ||
 169             rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
 170                 return -EIO;
 171
 172         if ((cifs_pdu == NULL) || (server == NULL))
 173                 return -EINVAL;
 174
 175         if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
 176             server->tcpStatus == CifsNeedNegotiate)
 177                 return rc;
 178
 179         if (!server->session_estab) {
 180                 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
 181                 return rc;
 182         }
 183
 184         cifs_pdu->Signature.Sequence.SequenceNumber =
 185                                 cpu_to_le32(server->sequence_number);
 186         cifs_pdu->Signature.Sequence.Reserved = 0;
 187
 188         *pexpected_response_sequence_number = ++server->sequence_number;
 189         ++server->sequence_number;
 190
 191         rc = cifs_calc_signature(rqst, server, smb_signature);
 192         if (rc)
 193                 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
 194         else
 195                 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
 196
 197         return rc;
 198 }
 199
 200 int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
 201                    __u32 *pexpected_response_sequence)
 202 {
 203         struct smb_rqst rqst = { .rq_iov = iov,
 204                                  .rq_nvec = n_vec };
 205
 206         return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
 207 }
 208
 209 /* must be called with server->srv_mutex held */
 210 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
 211                   __u32 *pexpected_response_sequence_number)
 212 {
 213         struct kvec iov[2];
 214
 215         iov[0].iov_base = cifs_pdu;
 216         iov[0].iov_len = 4;
 217         iov[1].iov_base = (char *)cifs_pdu + 4;
 218         iov[1].iov_len = be32_to_cpu(cifs_pdu->smb_buf_length);
 219
 220         return cifs_sign_smbv(iov, 2, server,
 221                               pexpected_response_sequence_number);
 222 }
 223
 224 int cifs_verify_signature(struct smb_rqst *rqst,
 225                           struct TCP_Server_Info *server,
 226                           __u32 expected_sequence_number)
 227 {
 228         unsigned int rc;
 229         char server_response_sig[8];
 230         char what_we_think_sig_should_be[20];
 231         struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
 232
 233         if (rqst->rq_iov[0].iov_len != 4 ||
 234             rqst->rq_iov[0].iov_base + 4 != rqst->rq_iov[1].iov_base)
 235                 return -EIO;
 236
 237         if (cifs_pdu == NULL || server == NULL)
 238                 return -EINVAL;
 239
 240         if (!server->session_estab)
 241                 return 0;
 242
 243         if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
 244                 struct smb_com_lock_req *pSMB =
 245                         (struct smb_com_lock_req *)cifs_pdu;
 246             if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
 247                         return 0;
 248         }
 249
 250         /* BB what if signatures are supposed to be on for session but
 251            server does not send one? BB */
 252
 253         /* Do not need to verify session setups with signature "BSRSPYL "  */
 254         if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
 255                 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
 256                          cifs_pdu->Command);
 257
 258         /* save off the origiginal signature so we can modify the smb and check
 259                 its signature against what the server sent */
 260         memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
 261
 262         cifs_pdu->Signature.Sequence.SequenceNumber =
 263                                         cpu_to_le32(expected_sequence_number);
 264         cifs_pdu->Signature.Sequence.Reserved = 0;
 265
 266         mutex_lock(&server->srv_mutex);
 267         rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
 268         mutex_unlock(&server->srv_mutex);
 269
 270         if (rc)
 271                 return rc;
 272
 273 /*      cifs_dump_mem("what we think it should be: ",
 274                       what_we_think_sig_should_be, 16); */
 275
 276         if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
 277                 return -EACCES;
 278         else
 279                 return 0;
 280
 281 }
 282
 283 /* first calculate 24 bytes ntlm response and then 16 byte session key */
 284 int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
 285 {
 286         int rc = 0;
 287         unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
 288         char temp_key[CIFS_SESS_KEY_SIZE];
 289
 290         if (!ses)
 291                 return -EINVAL;
 292
 293         ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
 294         if (!ses->auth_key.response)
 295                 return -ENOMEM;
 296
 297         ses->auth_key.len = temp_len;
 298
 299         rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
 300                         ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
 301         if (rc) {
 302                 cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
 303                          __func__, rc);
 304                 return rc;
 305         }
 306
 307         rc = E_md4hash(ses->password, temp_key, nls_cp);
 308         if (rc) {
 309                 cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
 310                          __func__, rc);
 311                 return rc;
 312         }
 313
 314         rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
 315         if (rc)
 316                 cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
 317                          __func__, rc);
 318
 319         return rc;
 320 }
 321
 322 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 323 int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
 324                         char *lnm_session_key)
 325 {
 326         int i;
 327         int rc;
 328         char password_with_pad[CIFS_ENCPWD_SIZE] = {0};
 329
 330         if (password)
 331                 strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
 332
 333         if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
 334                 memcpy(lnm_session_key, password_with_pad,
 335                         CIFS_ENCPWD_SIZE);
 336                 return 0;
 337         }
 338
 339         /* calculate old style session key */
 340         /* calling toupper is less broken than repeatedly
 341         calling nls_toupper would be since that will never
 342         work for UTF8, but neither handles multibyte code pages
 343         but the only alternative would be converting to UCS-16 (Unicode)
 344         (using a routine something like UniStrupr) then
 345         uppercasing and then converting back from Unicode - which
 346         would only worth doing it if we knew it were utf8. Basically
 347         utf8 and other multibyte codepages each need their own strupper
 348         function since a byte at a time will ont work. */
 349
 350         for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
 351                 password_with_pad[i] = toupper(password_with_pad[i]);
 352
 353         rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
 354
 355         return rc;
 356 }
 357 #endif /* CIFS_WEAK_PW_HASH */
 358
 359 /* Build a proper attribute value/target info pairs blob.
 360  * Fill in netbios and dns domain name and workstation name
 361  * and client time (total five av pairs and + one end of fields indicator.
 362  * Allocate domain name which gets freed when session struct is deallocated.
 363  */
 364 static int
 365 build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
 366 {
 367         unsigned int dlen;
 368         unsigned int size = 2 * sizeof(struct ntlmssp2_name);
 369         char *defdmname = "WORKGROUP";
 370         unsigned char *blobptr;
 371         struct ntlmssp2_name *attrptr;
 372
 373         if (!ses->domainName) {
 374                 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
 375                 if (!ses->domainName)
 376                         return -ENOMEM;
 377         }
 378
 379         dlen = strlen(ses->domainName);
 380
 381         /*
 382          * The length of this blob is two times the size of a
 383          * structure (av pair) which holds name/size
 384          * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
 385          * unicode length of a netbios domain name
 386          */
 387         ses->auth_key.len = size + 2 * dlen;
 388         ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
 389         if (!ses->auth_key.response) {
 390                 ses->auth_key.len = 0;
 391                 return -ENOMEM;
 392         }
 393
 394         blobptr = ses->auth_key.response;
 395         attrptr = (struct ntlmssp2_name *) blobptr;
 396
 397         /*
 398          * As defined in MS-NTLM 3.3.2, just this av pair field
 399          * is sufficient as part of the temp
 400          */
 401         attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
 402         attrptr->length = cpu_to_le16(2 * dlen);
 403         blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
 404         cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
 405
 406         return 0;
 407 }
 408
 409 /* Server has provided av pairs/target info in the type 2 challenge
 410  * packet and we have plucked it and stored within smb session.
 411  * We parse that blob here to find netbios domain name to be used
 412  * as part of ntlmv2 authentication (in Target String), if not already
 413  * specified on the command line.
 414  * If this function returns without any error but without fetching
 415  * domain name, authentication may fail against some server but
 416  * may not fail against other (those who are not very particular
 417  * about target string i.e. for some, just user name might suffice.
 418  */
 419 static int
 420 find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
 421 {
 422         unsigned int attrsize;
 423         unsigned int type;
 424         unsigned int onesize = sizeof(struct ntlmssp2_name);
 425         unsigned char *blobptr;
 426         unsigned char *blobend;
 427         struct ntlmssp2_name *attrptr;
 428
 429         if (!ses->auth_key.len || !ses->auth_key.response)
 430                 return 0;
 431
 432         blobptr = ses->auth_key.response;
 433         blobend = blobptr + ses->auth_key.len;
 434
 435         while (blobptr + onesize < blobend) {
 436                 attrptr = (struct ntlmssp2_name *) blobptr;
 437                 type = le16_to_cpu(attrptr->type);
 438                 if (type == NTLMSSP_AV_EOL)
 439                         break;
 440                 blobptr += 2; /* advance attr type */
 441                 attrsize = le16_to_cpu(attrptr->length);
 442                 blobptr += 2; /* advance attr size */
 443                 if (blobptr + attrsize > blobend)
 444                         break;
 445                 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
 446                         if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
 447                                 break;
 448                         if (!ses->domainName) {
 449                                 ses->domainName =
 450                                         kmalloc(attrsize + 1, GFP_KERNEL);
 451                                 if (!ses->domainName)
 452                                                 return -ENOMEM;
 453                                 cifs_from_utf16(ses->domainName,
 454                                         (__le16 *)blobptr, attrsize, attrsize,
 455                                         nls_cp, NO_MAP_UNI_RSVD);
 456                                 break;
 457                         }
 458                 }
 459                 blobptr += attrsize; /* advance attr  value */
 460         }
 461
 462         return 0;
 463 }
 464
 465 /* Server has provided av pairs/target info in the type 2 challenge
 466  * packet and we have plucked it and stored within smb session.
 467  * We parse that blob here to find the server given timestamp
 468  * as part of ntlmv2 authentication (or local current time as
 469  * default in case of failure)
 470  */
 471 static __le64
 472 find_timestamp(struct cifs_ses *ses)
 473 {
 474         unsigned int attrsize;
 475         unsigned int type;
 476         unsigned int onesize = sizeof(struct ntlmssp2_name);
 477         unsigned char *blobptr;
 478         unsigned char *blobend;
 479         struct ntlmssp2_name *attrptr;
 480         struct timespec ts;
 481
 482         if (!ses->auth_key.len || !ses->auth_key.response)
 483                 return 0;
 484
 485         blobptr = ses->auth_key.response;
 486         blobend = blobptr + ses->auth_key.len;
 487
 488         while (blobptr + onesize < blobend) {
 489                 attrptr = (struct ntlmssp2_name *) blobptr;
 490                 type = le16_to_cpu(attrptr->type);
 491                 if (type == NTLMSSP_AV_EOL)
 492                         break;
 493                 blobptr += 2; /* advance attr type */
 494                 attrsize = le16_to_cpu(attrptr->length);
 495                 blobptr += 2; /* advance attr size */
 496                 if (blobptr + attrsize > blobend)
 497                         break;
 498                 if (type == NTLMSSP_AV_TIMESTAMP) {
 499                         if (attrsize == sizeof(u64))
 500                                 return *((__le64 *)blobptr);
 501                 }
 502                 blobptr += attrsize; /* advance attr value */
 503         }
 504
 505         ktime_get_real_ts(&ts);
 506         return cpu_to_le64(cifs_UnixTimeToNT(ts));
 507 }
 508
 509 static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
 510                             const struct nls_table *nls_cp)
 511 {
 512         int rc = 0;
 513         int len;
 514         char nt_hash[CIFS_NTHASH_SIZE];
 515         __le16 *user;
 516         wchar_t *domain;
 517         wchar_t *server;
 518
 519         if (!ses->server->secmech.sdeschmacmd5) {
 520                 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
 521                 return -1;
 522         }
 523
 524         /* calculate md4 hash of password */
 525         E_md4hash(ses->password, nt_hash, nls_cp);
 526
 527         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
 528                                 CIFS_NTHASH_SIZE);
 529         if (rc) {
 530                 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
 531                 return rc;
 532         }
 533
 534         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 535         if (rc) {
 536                 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
 537                 return rc;
 538         }
 539
 540         /* convert ses->user_name to unicode */
 541         len = ses->user_name ? strlen(ses->user_name) : 0;
 542         user = kmalloc(2 + (len * 2), GFP_KERNEL);
 543         if (user == NULL) {
 544                 rc = -ENOMEM;
 545                 return rc;
 546         }
 547
 548         if (len) {
 549                 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
 550                 UniStrupr(user);
 551         } else {
 552                 memset(user, '\0', 2);
 553         }
 554
 555         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 556                                 (char *)user, 2 * len);
 557         kfree(user);
 558         if (rc) {
 559                 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
 560                 return rc;
 561         }
 562
 563         /* convert ses->domainName to unicode and uppercase */
 564         if (ses->domainName) {
 565                 len = strlen(ses->domainName);
 566
 567                 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
 568                 if (domain == NULL) {
 569                         rc = -ENOMEM;
 570                         return rc;
 571                 }
 572                 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
 573                                       nls_cp);
 574                 rc =
 575                 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 576                                         (char *)domain, 2 * len);
 577                 kfree(domain);
 578                 if (rc) {
 579                         cifs_dbg(VFS, "%s: Could not update with domain\n",
 580                                  __func__);
 581                         return rc;
 582                 }
 583         } else {
 584                 /* We use ses->serverName if no domain name available */
 585                 len = strlen(ses->serverName);
 586
 587                 server = kmalloc(2 + (len * 2), GFP_KERNEL);
 588                 if (server == NULL) {
 589                         rc = -ENOMEM;
 590                         return rc;
 591                 }
 592                 len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
 593                                         nls_cp);
 594                 rc =
 595                 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 596                                         (char *)server, 2 * len);
 597                 kfree(server);
 598                 if (rc) {
 599                         cifs_dbg(VFS, "%s: Could not update with server\n",
 600                                  __func__);
 601                         return rc;
 602                 }
 603         }
 604
 605         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 606                                         ntlmv2_hash);
 607         if (rc)
 608                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 609
 610         return rc;
 611 }
 612
 613 static int
 614 CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
 615 {
 616         int rc;
 617         struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
 618             (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
 619         unsigned int hash_len;
 620
 621         /* The MD5 hash starts at challenge_key.key */
 622         hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
 623                 offsetof(struct ntlmv2_resp, challenge.key[0]));
 624
 625         if (!ses->server->secmech.sdeschmacmd5) {
 626                 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
 627                 return -1;
 628         }
 629
 630         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
 631                                  ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
 632         if (rc) {
 633                 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
 634                          __func__);
 635                 return rc;
 636         }
 637
 638         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 639         if (rc) {
 640                 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
 641                 return rc;
 642         }
 643
 644         if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
 645                 memcpy(ntlmv2->challenge.key,
 646                        ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
 647         else
 648                 memcpy(ntlmv2->challenge.key,
 649                        ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
 650         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 651                                  ntlmv2->challenge.key, hash_len);
 652         if (rc) {
 653                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 654                 return rc;
 655         }
 656
 657         /* Note that the MD5 digest over writes anon.challenge_key.key */
 658         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 659                                 ntlmv2->ntlmv2_hash);
 660         if (rc)
 661                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 662
 663         return rc;
 664 }
 665
 666 static int crypto_hmacmd5_alloc(struct TCP_Server_Info *server)
 667 {
 668         int rc;
 669         unsigned int size;
 670
 671         /* check if already allocated */
 672         if (server->secmech.sdeschmacmd5)
 673                 return 0;
 674
 675         server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
 676         if (IS_ERR(server->secmech.hmacmd5)) {
 677                 cifs_dbg(VFS, "could not allocate crypto hmacmd5\n");
 678                 rc = PTR_ERR(server->secmech.hmacmd5);
 679                 server->secmech.hmacmd5 = NULL;
 680                 return rc;
 681         }
 682
 683         size = sizeof(struct shash_desc) +
 684                         crypto_shash_descsize(server->secmech.hmacmd5);
 685         server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
 686         if (!server->secmech.sdeschmacmd5) {
 687                 crypto_free_shash(server->secmech.hmacmd5);
 688                 server->secmech.hmacmd5 = NULL;
 689                 return -ENOMEM;
 690         }
 691         server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
 692         server->secmech.sdeschmacmd5->shash.flags = 0x0;
 693
 694         return 0;
 695 }
 696
 697 int
 698 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 699 {
 700         int rc;
 701         int baselen;
 702         unsigned int tilen;
 703         struct ntlmv2_resp *ntlmv2;
 704         char ntlmv2_hash[16];
 705         unsigned char *tiblob = NULL; /* target info blob */
 706         __le64 rsp_timestamp;
 707
 708         if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
 709                 if (!ses->domainName) {
 710                         if (ses->domainAuto) {
 711                                 rc = find_domain_name(ses, nls_cp);
 712                                 if (rc) {
 713                                         cifs_dbg(VFS, "error %d finding domain name\n",
 714                                                  rc);
 715                                         goto setup_ntlmv2_rsp_ret;
 716                                 }
 717                         } else {
 718                                 ses->domainName = kstrdup("", GFP_KERNEL);
 719                         }
 720                 }
 721         } else {
 722                 rc = build_avpair_blob(ses, nls_cp);
 723                 if (rc) {
 724                         cifs_dbg(VFS, "error %d building av pair blob\n", rc);
 725                         goto setup_ntlmv2_rsp_ret;
 726                 }
 727         }
 728
 729         /* Must be within 5 minutes of the server (or in range +/-2h
 730          * in case of Mac OS X), so simply carry over server timestamp
 731          * (as Windows 7 does)
 732          */
 733         rsp_timestamp = find_timestamp(ses);
 734
 735         baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
 736         tilen = ses->auth_key.len;
 737         tiblob = ses->auth_key.response;
 738
 739         ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
 740         if (!ses->auth_key.response) {
 741                 rc = -ENOMEM;
 742                 ses->auth_key.len = 0;
 743                 goto setup_ntlmv2_rsp_ret;
 744         }
 745         ses->auth_key.len += baselen;
 746
 747         ntlmv2 = (struct ntlmv2_resp *)
 748                         (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
 749         ntlmv2->blob_signature = cpu_to_le32(0x00000101);
 750         ntlmv2->reserved = 0;
 751         ntlmv2->time = rsp_timestamp;
 752
 753         get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
 754         ntlmv2->reserved2 = 0;
 755
 756         memcpy(ses->auth_key.response + baselen, tiblob, tilen);
 757
 758         mutex_lock(&ses->server->srv_mutex);
 759
 760         rc = crypto_hmacmd5_alloc(ses->server);
 761         if (rc) {
 762                 cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
 763                 goto unlock;
 764         }
 765
 766         /* calculate ntlmv2_hash */
 767         rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
 768         if (rc) {
 769                 cifs_dbg(VFS, "could not get v2 hash rc %d\n", rc);
 770                 goto unlock;
 771         }
 772
 773         /* calculate first part of the client response (CR1) */
 774         rc = CalcNTLMv2_response(ses, ntlmv2_hash);
 775         if (rc) {
 776                 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
 777                 goto unlock;
 778         }
 779
 780         /* now calculate the session key for NTLMv2 */
 781         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
 782                 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
 783         if (rc) {
 784                 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
 785                          __func__);
 786                 goto unlock;
 787         }
 788
 789         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 790         if (rc) {
 791                 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
 792                 goto unlock;
 793         }
 794
 795         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 796                 ntlmv2->ntlmv2_hash,
 797                 CIFS_HMAC_MD5_HASH_SIZE);
 798         if (rc) {
 799                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 800                 goto unlock;
 801         }
 802
 803         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 804                 ses->auth_key.response);
 805         if (rc)
 806                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 807
 808 unlock:
 809         mutex_unlock(&ses->server->srv_mutex);
 810 setup_ntlmv2_rsp_ret:
 811         kfree(tiblob);
 812
 813         return rc;
 814 }
 815
 816 int
 817 calc_seckey(struct cifs_ses *ses)
 818 {
 819         int rc;
 820         struct crypto_skcipher *tfm_arc4;
 821         struct scatterlist sgin, sgout;
 822         struct skcipher_request *req;
 823         unsigned char *sec_key;
 824
 825         sec_key = kmalloc(CIFS_SESS_KEY_SIZE, GFP_KERNEL);
 826         if (sec_key == NULL)
 827                 return -ENOMEM;
 828
 829         get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
 830
 831         tfm_arc4 = crypto_alloc_skcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
 832         if (IS_ERR(tfm_arc4)) {
 833                 rc = PTR_ERR(tfm_arc4);
 834                 cifs_dbg(VFS, "could not allocate crypto API arc4\n");
 835                 goto out;
 836         }
 837
 838         rc = crypto_skcipher_setkey(tfm_arc4, ses->auth_key.response,
 839                                         CIFS_SESS_KEY_SIZE);
 840         if (rc) {
 841                 cifs_dbg(VFS, "%s: Could not set response as a key\n",
 842                          __func__);
 843                 goto out_free_cipher;
 844         }
 845
 846         req = skcipher_request_alloc(tfm_arc4, GFP_KERNEL);
 847         if (!req) {
 848                 rc = -ENOMEM;
 849                 cifs_dbg(VFS, "could not allocate crypto API arc4 request\n");
 850                 goto out_free_cipher;
 851         }
 852
 853         sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
 854         sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
 855
 856         skcipher_request_set_callback(req, 0, NULL, NULL);
 857         skcipher_request_set_crypt(req, &sgin, &sgout, CIFS_CPHTXT_SIZE, NULL);
 858
 859         rc = crypto_skcipher_encrypt(req);
 860         skcipher_request_free(req);
 861         if (rc) {
 862                 cifs_dbg(VFS, "could not encrypt session key rc: %d\n", rc);
 863                 goto out_free_cipher;
 864         }
 865
 866         /* make secondary_key/nonce as session key */
 867         memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
 868         /* and make len as that of session key only */
 869         ses->auth_key.len = CIFS_SESS_KEY_SIZE;
 870
 871 out_free_cipher:
 872         crypto_free_skcipher(tfm_arc4);
 873 out:
 874         kfree(sec_key);
 875         return rc;
 876 }
 877
 878 void
 879 cifs_crypto_secmech_release(struct TCP_Server_Info *server)
 880 {
 881         if (server->secmech.cmacaes) {
 882                 crypto_free_shash(server->secmech.cmacaes);
 883                 server->secmech.cmacaes = NULL;
 884         }
 885
 886         if (server->secmech.hmacsha256) {
 887                 crypto_free_shash(server->secmech.hmacsha256);
 888                 server->secmech.hmacsha256 = NULL;
 889         }
 890
 891         if (server->secmech.md5) {
 892                 crypto_free_shash(server->secmech.md5);
 893                 server->secmech.md5 = NULL;
 894         }
 895
 896         if (server->secmech.hmacmd5) {
 897                 crypto_free_shash(server->secmech.hmacmd5);
 898                 server->secmech.hmacmd5 = NULL;
 899         }
 900
 901         if (server->secmech.ccmaesencrypt) {
 902                 crypto_free_aead(server->secmech.ccmaesencrypt);
 903                 server->secmech.ccmaesencrypt = NULL;
 904         }
 905
 906         if (server->secmech.ccmaesdecrypt) {
 907                 crypto_free_aead(server->secmech.ccmaesdecrypt);
 908                 server->secmech.ccmaesdecrypt = NULL;
 909         }
 910
 911         kfree(server->secmech.sdesccmacaes);
 912         server->secmech.sdesccmacaes = NULL;
 913         kfree(server->secmech.sdeschmacsha256);
 914         server->secmech.sdeschmacsha256 = NULL;
 915         kfree(server->secmech.sdeschmacmd5);
 916         server->secmech.sdeschmacmd5 = NULL;
 917         kfree(server->secmech.sdescmd5);
 918         server->secmech.sdescmd5 = NULL;
 919 }