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
  37 static int
  38 cifs_crypto_shash_md5_allocate(struct TCP_Server_Info *server)
  39 {
  40         int rc;
  41         unsigned int size;
  42
  43         if (server->secmech.sdescmd5 != NULL)
  44                 return 0; /* already allocated */
  45
  46         server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
  47         if (IS_ERR(server->secmech.md5)) {
  48                 cifs_dbg(VFS, "could not allocate crypto md5\n");
  49                 rc = PTR_ERR(server->secmech.md5);
  50                 server->secmech.md5 = NULL;
  51                 return rc;
  52         }
  53
  54         size = sizeof(struct shash_desc) +
  55                         crypto_shash_descsize(server->secmech.md5);
  56         server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
  57         if (!server->secmech.sdescmd5) {
  58                 crypto_free_shash(server->secmech.md5);
  59                 server->secmech.md5 = NULL;
  60                 return -ENOMEM;
  61         }
  62         server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
  63         server->secmech.sdescmd5->shash.flags = 0x0;
  64
  65         return 0;
  66 }
  67
  68 /*
  69  * Calculate and return the CIFS signature based on the mac key and SMB PDU.
  70  * The 16 byte signature must be allocated by the caller. Note we only use the
  71  * 1st eight bytes and that the smb header signature field on input contains
  72  * the sequence number before this function is called. Also, this function
  73  * should be called with the server->srv_mutex held.
  74  */
  75 static int cifs_calc_signature(struct smb_rqst *rqst,
  76                         struct TCP_Server_Info *server, char *signature)
  77 {
  78         int i;
  79         int rc;
  80         struct kvec *iov = rqst->rq_iov;
  81         int n_vec = rqst->rq_nvec;
  82
  83         if (iov == NULL || signature == NULL || server == NULL)
  84                 return -EINVAL;
  85
  86         if (!server->secmech.sdescmd5) {
  87                 rc = cifs_crypto_shash_md5_allocate(server);
  88                 if (rc) {
  89                         cifs_dbg(VFS, "%s: Can't alloc md5 crypto\n", __func__);
  90                         return -1;
  91                 }
  92         }
  93
  94         rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
  95         if (rc) {
  96                 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
  97                 return rc;
  98         }
  99
 100         rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
 101                 server->session_key.response, server->session_key.len);
 102         if (rc) {
 103                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 104                 return rc;
 105         }
 106
 107         for (i = 0; i < n_vec; i++) {
 108                 if (iov[i].iov_len == 0)
 109                         continue;
 110                 if (iov[i].iov_base == NULL) {
 111                         cifs_dbg(VFS, "null iovec entry\n");
 112                         return -EIO;
 113                 }
 114                 /* The first entry includes a length field (which does not get
 115                    signed that occupies the first 4 bytes before the header */
 116                 if (i == 0) {
 117                         if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
 118                                 break; /* nothing to sign or corrupt header */
 119                         rc =
 120                         crypto_shash_update(&server->secmech.sdescmd5->shash,
 121                                 iov[i].iov_base + 4, iov[i].iov_len - 4);
 122                 } else {
 123                         rc =
 124                         crypto_shash_update(&server->secmech.sdescmd5->shash,
 125                                 iov[i].iov_base, iov[i].iov_len);
 126                 }
 127                 if (rc) {
 128                         cifs_dbg(VFS, "%s: Could not update with payload\n",
 129                                  __func__);
 130                         return rc;
 131                 }
 132         }
 133
 134         /* now hash over the rq_pages array */
 135         for (i = 0; i < rqst->rq_npages; i++) {
 136                 struct kvec p_iov;
 137
 138                 cifs_rqst_page_to_kvec(rqst, i, &p_iov);
 139                 crypto_shash_update(&server->secmech.sdescmd5->shash,
 140                                         p_iov.iov_base, p_iov.iov_len);
 141                 kunmap(rqst->rq_pages[i]);
 142         }
 143
 144         rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
 145         if (rc)
 146                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 147
 148         return rc;
 149 }
 150
 151 /* must be called with server->srv_mutex held */
 152 int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
 153                    __u32 *pexpected_response_sequence_number)
 154 {
 155         int rc = 0;
 156         char smb_signature[20];
 157         struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
 158
 159         if ((cifs_pdu == NULL) || (server == NULL))
 160                 return -EINVAL;
 161
 162         if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
 163             server->tcpStatus == CifsNeedNegotiate)
 164                 return rc;
 165
 166         if (!server->session_estab) {
 167                 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
 168                 return rc;
 169         }
 170
 171         cifs_pdu->Signature.Sequence.SequenceNumber =
 172                                 cpu_to_le32(server->sequence_number);
 173         cifs_pdu->Signature.Sequence.Reserved = 0;
 174
 175         *pexpected_response_sequence_number = ++server->sequence_number;
 176         ++server->sequence_number;
 177
 178         rc = cifs_calc_signature(rqst, server, smb_signature);
 179         if (rc)
 180                 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
 181         else
 182                 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
 183
 184         return rc;
 185 }
 186
 187 int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
 188                    __u32 *pexpected_response_sequence)
 189 {
 190         struct smb_rqst rqst = { .rq_iov = iov,
 191                                  .rq_nvec = n_vec };
 192
 193         return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
 194 }
 195
 196 /* must be called with server->srv_mutex held */
 197 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
 198                   __u32 *pexpected_response_sequence_number)
 199 {
 200         struct kvec iov;
 201
 202         iov.iov_base = cifs_pdu;
 203         iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
 204
 205         return cifs_sign_smbv(&iov, 1, server,
 206                               pexpected_response_sequence_number);
 207 }
 208
 209 int cifs_verify_signature(struct smb_rqst *rqst,
 210                           struct TCP_Server_Info *server,
 211                           __u32 expected_sequence_number)
 212 {
 213         unsigned int rc;
 214         char server_response_sig[8];
 215         char what_we_think_sig_should_be[20];
 216         struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
 217
 218         if (cifs_pdu == NULL || server == NULL)
 219                 return -EINVAL;
 220
 221         if (!server->session_estab)
 222                 return 0;
 223
 224         if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
 225                 struct smb_com_lock_req *pSMB =
 226                         (struct smb_com_lock_req *)cifs_pdu;
 227             if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
 228                         return 0;
 229         }
 230
 231         /* BB what if signatures are supposed to be on for session but
 232            server does not send one? BB */
 233
 234         /* Do not need to verify session setups with signature "BSRSPYL "  */
 235         if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
 236                 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
 237                          cifs_pdu->Command);
 238
 239         /* save off the origiginal signature so we can modify the smb and check
 240                 its signature against what the server sent */
 241         memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
 242
 243         cifs_pdu->Signature.Sequence.SequenceNumber =
 244                                         cpu_to_le32(expected_sequence_number);
 245         cifs_pdu->Signature.Sequence.Reserved = 0;
 246
 247         mutex_lock(&server->srv_mutex);
 248         rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
 249         mutex_unlock(&server->srv_mutex);
 250
 251         if (rc)
 252                 return rc;
 253
 254 /*      cifs_dump_mem("what we think it should be: ",
 255                       what_we_think_sig_should_be, 16); */
 256
 257         if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
 258                 return -EACCES;
 259         else
 260                 return 0;
 261
 262 }
 263
 264 /* first calculate 24 bytes ntlm response and then 16 byte session key */
 265 int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
 266 {
 267         int rc = 0;
 268         unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
 269         char temp_key[CIFS_SESS_KEY_SIZE];
 270
 271         if (!ses)
 272                 return -EINVAL;
 273
 274         ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
 275         if (!ses->auth_key.response)
 276                 return -ENOMEM;
 277
 278         ses->auth_key.len = temp_len;
 279
 280         rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
 281                         ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
 282         if (rc) {
 283                 cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
 284                          __func__, rc);
 285                 return rc;
 286         }
 287
 288         rc = E_md4hash(ses->password, temp_key, nls_cp);
 289         if (rc) {
 290                 cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
 291                          __func__, rc);
 292                 return rc;
 293         }
 294
 295         rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
 296         if (rc)
 297                 cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
 298                          __func__, rc);
 299
 300         return rc;
 301 }
 302
 303 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 304 int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
 305                         char *lnm_session_key)
 306 {
 307         int i;
 308         int rc;
 309         char password_with_pad[CIFS_ENCPWD_SIZE];
 310
 311         memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
 312         if (password)
 313                 strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
 314
 315         if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
 316                 memcpy(lnm_session_key, password_with_pad,
 317                         CIFS_ENCPWD_SIZE);
 318                 return 0;
 319         }
 320
 321         /* calculate old style session key */
 322         /* calling toupper is less broken than repeatedly
 323         calling nls_toupper would be since that will never
 324         work for UTF8, but neither handles multibyte code pages
 325         but the only alternative would be converting to UCS-16 (Unicode)
 326         (using a routine something like UniStrupr) then
 327         uppercasing and then converting back from Unicode - which
 328         would only worth doing it if we knew it were utf8. Basically
 329         utf8 and other multibyte codepages each need their own strupper
 330         function since a byte at a time will ont work. */
 331
 332         for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
 333                 password_with_pad[i] = toupper(password_with_pad[i]);
 334
 335         rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
 336
 337         return rc;
 338 }
 339 #endif /* CIFS_WEAK_PW_HASH */
 340
 341 /* Build a proper attribute value/target info pairs blob.
 342  * Fill in netbios and dns domain name and workstation name
 343  * and client time (total five av pairs and + one end of fields indicator.
 344  * Allocate domain name which gets freed when session struct is deallocated.
 345  */
 346 static int
 347 build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
 348 {
 349         unsigned int dlen;
 350         unsigned int size = 2 * sizeof(struct ntlmssp2_name);
 351         char *defdmname = "WORKGROUP";
 352         unsigned char *blobptr;
 353         struct ntlmssp2_name *attrptr;
 354
 355         if (!ses->domainName) {
 356                 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
 357                 if (!ses->domainName)
 358                         return -ENOMEM;
 359         }
 360
 361         dlen = strlen(ses->domainName);
 362
 363         /*
 364          * The length of this blob is two times the size of a
 365          * structure (av pair) which holds name/size
 366          * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
 367          * unicode length of a netbios domain name
 368          */
 369         ses->auth_key.len = size + 2 * dlen;
 370         ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
 371         if (!ses->auth_key.response) {
 372                 ses->auth_key.len = 0;
 373                 return -ENOMEM;
 374         }
 375
 376         blobptr = ses->auth_key.response;
 377         attrptr = (struct ntlmssp2_name *) blobptr;
 378
 379         /*
 380          * As defined in MS-NTLM 3.3.2, just this av pair field
 381          * is sufficient as part of the temp
 382          */
 383         attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
 384         attrptr->length = cpu_to_le16(2 * dlen);
 385         blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
 386         cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
 387
 388         return 0;
 389 }
 390
 391 /* Server has provided av pairs/target info in the type 2 challenge
 392  * packet and we have plucked it and stored within smb session.
 393  * We parse that blob here to find netbios domain name to be used
 394  * as part of ntlmv2 authentication (in Target String), if not already
 395  * specified on the command line.
 396  * If this function returns without any error but without fetching
 397  * domain name, authentication may fail against some server but
 398  * may not fail against other (those who are not very particular
 399  * about target string i.e. for some, just user name might suffice.
 400  */
 401 static int
 402 find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
 403 {
 404         unsigned int attrsize;
 405         unsigned int type;
 406         unsigned int onesize = sizeof(struct ntlmssp2_name);
 407         unsigned char *blobptr;
 408         unsigned char *blobend;
 409         struct ntlmssp2_name *attrptr;
 410
 411         if (!ses->auth_key.len || !ses->auth_key.response)
 412                 return 0;
 413
 414         blobptr = ses->auth_key.response;
 415         blobend = blobptr + ses->auth_key.len;
 416
 417         while (blobptr + onesize < blobend) {
 418                 attrptr = (struct ntlmssp2_name *) blobptr;
 419                 type = le16_to_cpu(attrptr->type);
 420                 if (type == NTLMSSP_AV_EOL)
 421                         break;
 422                 blobptr += 2; /* advance attr type */
 423                 attrsize = le16_to_cpu(attrptr->length);
 424                 blobptr += 2; /* advance attr size */
 425                 if (blobptr + attrsize > blobend)
 426                         break;
 427                 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
 428                         if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
 429                                 break;
 430                         if (!ses->domainName) {
 431                                 ses->domainName =
 432                                         kmalloc(attrsize + 1, GFP_KERNEL);
 433                                 if (!ses->domainName)
 434                                                 return -ENOMEM;
 435                                 cifs_from_utf16(ses->domainName,
 436                                         (__le16 *)blobptr, attrsize, attrsize,
 437                                         nls_cp, NO_MAP_UNI_RSVD);
 438                                 break;
 439                         }
 440                 }
 441                 blobptr += attrsize; /* advance attr  value */
 442         }
 443
 444         return 0;
 445 }
 446
 447 /* Server has provided av pairs/target info in the type 2 challenge
 448  * packet and we have plucked it and stored within smb session.
 449  * We parse that blob here to find the server given timestamp
 450  * as part of ntlmv2 authentication (or local current time as
 451  * default in case of failure)
 452  */
 453 static __le64
 454 find_timestamp(struct cifs_ses *ses)
 455 {
 456         unsigned int attrsize;
 457         unsigned int type;
 458         unsigned int onesize = sizeof(struct ntlmssp2_name);
 459         unsigned char *blobptr;
 460         unsigned char *blobend;
 461         struct ntlmssp2_name *attrptr;
 462
 463         if (!ses->auth_key.len || !ses->auth_key.response)
 464                 return 0;
 465
 466         blobptr = ses->auth_key.response;
 467         blobend = blobptr + ses->auth_key.len;
 468
 469         while (blobptr + onesize < blobend) {
 470                 attrptr = (struct ntlmssp2_name *) blobptr;
 471                 type = le16_to_cpu(attrptr->type);
 472                 if (type == NTLMSSP_AV_EOL)
 473                         break;
 474                 blobptr += 2; /* advance attr type */
 475                 attrsize = le16_to_cpu(attrptr->length);
 476                 blobptr += 2; /* advance attr size */
 477                 if (blobptr + attrsize > blobend)
 478                         break;
 479                 if (type == NTLMSSP_AV_TIMESTAMP) {
 480                         if (attrsize == sizeof(u64))
 481                                 return *((__le64 *)blobptr);
 482                 }
 483                 blobptr += attrsize; /* advance attr value */
 484         }
 485
 486         return cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
 487 }
 488
 489 static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
 490                             const struct nls_table *nls_cp)
 491 {
 492         int rc = 0;
 493         int len;
 494         char nt_hash[CIFS_NTHASH_SIZE];
 495         __le16 *user;
 496         wchar_t *domain;
 497         wchar_t *server;
 498
 499         if (!ses->server->secmech.sdeschmacmd5) {
 500                 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
 501                 return -1;
 502         }
 503
 504         /* calculate md4 hash of password */
 505         E_md4hash(ses->password, nt_hash, nls_cp);
 506
 507         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
 508                                 CIFS_NTHASH_SIZE);
 509         if (rc) {
 510                 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
 511                 return rc;
 512         }
 513
 514         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 515         if (rc) {
 516                 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
 517                 return rc;
 518         }
 519
 520         /* convert ses->user_name to unicode */
 521         len = ses->user_name ? strlen(ses->user_name) : 0;
 522         user = kmalloc(2 + (len * 2), GFP_KERNEL);
 523         if (user == NULL) {
 524                 rc = -ENOMEM;
 525                 return rc;
 526         }
 527
 528         if (len) {
 529                 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
 530                 UniStrupr(user);
 531         } else {
 532                 memset(user, '\0', 2);
 533         }
 534
 535         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 536                                 (char *)user, 2 * len);
 537         kfree(user);
 538         if (rc) {
 539                 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
 540                 return rc;
 541         }
 542
 543         /* convert ses->domainName to unicode and uppercase */
 544         if (ses->domainName) {
 545                 len = strlen(ses->domainName);
 546
 547                 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
 548                 if (domain == NULL) {
 549                         rc = -ENOMEM;
 550                         return rc;
 551                 }
 552                 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
 553                                       nls_cp);
 554                 rc =
 555                 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 556                                         (char *)domain, 2 * len);
 557                 kfree(domain);
 558                 if (rc) {
 559                         cifs_dbg(VFS, "%s: Could not update with domain\n",
 560                                  __func__);
 561                         return rc;
 562                 }
 563         } else {
 564                 /* We use ses->serverName if no domain name available */
 565                 len = strlen(ses->serverName);
 566
 567                 server = kmalloc(2 + (len * 2), GFP_KERNEL);
 568                 if (server == NULL) {
 569                         rc = -ENOMEM;
 570                         return rc;
 571                 }
 572                 len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
 573                                         nls_cp);
 574                 rc =
 575                 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 576                                         (char *)server, 2 * len);
 577                 kfree(server);
 578                 if (rc) {
 579                         cifs_dbg(VFS, "%s: Could not update with server\n",
 580                                  __func__);
 581                         return rc;
 582                 }
 583         }
 584
 585         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 586                                         ntlmv2_hash);
 587         if (rc)
 588                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 589
 590         return rc;
 591 }
 592
 593 static int
 594 CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
 595 {
 596         int rc;
 597         struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
 598             (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
 599         unsigned int hash_len;
 600
 601         /* The MD5 hash starts at challenge_key.key */
 602         hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
 603                 offsetof(struct ntlmv2_resp, challenge.key[0]));
 604
 605         if (!ses->server->secmech.sdeschmacmd5) {
 606                 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
 607                 return -1;
 608         }
 609
 610         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
 611                                  ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
 612         if (rc) {
 613                 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
 614                          __func__);
 615                 return rc;
 616         }
 617
 618         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 619         if (rc) {
 620                 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
 621                 return rc;
 622         }
 623
 624         if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
 625                 memcpy(ntlmv2->challenge.key,
 626                        ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
 627         else
 628                 memcpy(ntlmv2->challenge.key,
 629                        ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
 630         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 631                                  ntlmv2->challenge.key, hash_len);
 632         if (rc) {
 633                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 634                 return rc;
 635         }
 636
 637         /* Note that the MD5 digest over writes anon.challenge_key.key */
 638         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 639                                 ntlmv2->ntlmv2_hash);
 640         if (rc)
 641                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 642
 643         return rc;
 644 }
 645
 646 static int crypto_hmacmd5_alloc(struct TCP_Server_Info *server)
 647 {
 648         int rc;
 649         unsigned int size;
 650
 651         /* check if already allocated */
 652         if (server->secmech.sdeschmacmd5)
 653                 return 0;
 654
 655         server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
 656         if (IS_ERR(server->secmech.hmacmd5)) {
 657                 cifs_dbg(VFS, "could not allocate crypto hmacmd5\n");
 658                 rc = PTR_ERR(server->secmech.hmacmd5);
 659                 server->secmech.hmacmd5 = NULL;
 660                 return rc;
 661         }
 662
 663         size = sizeof(struct shash_desc) +
 664                         crypto_shash_descsize(server->secmech.hmacmd5);
 665         server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
 666         if (!server->secmech.sdeschmacmd5) {
 667                 crypto_free_shash(server->secmech.hmacmd5);
 668                 server->secmech.hmacmd5 = NULL;
 669                 return -ENOMEM;
 670         }
 671         server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
 672         server->secmech.sdeschmacmd5->shash.flags = 0x0;
 673
 674         return 0;
 675 }
 676
 677 int
 678 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 679 {
 680         int rc;
 681         int baselen;
 682         unsigned int tilen;
 683         struct ntlmv2_resp *ntlmv2;
 684         char ntlmv2_hash[16];
 685         unsigned char *tiblob = NULL; /* target info blob */
 686         __le64 rsp_timestamp;
 687
 688         if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
 689                 if (!ses->domainName) {
 690                         rc = find_domain_name(ses, nls_cp);
 691                         if (rc) {
 692                                 cifs_dbg(VFS, "error %d finding domain name\n",
 693                                          rc);
 694                                 goto setup_ntlmv2_rsp_ret;
 695                         }
 696                 }
 697         } else {
 698                 rc = build_avpair_blob(ses, nls_cp);
 699                 if (rc) {
 700                         cifs_dbg(VFS, "error %d building av pair blob\n", rc);
 701                         goto setup_ntlmv2_rsp_ret;
 702                 }
 703         }
 704
 705         /* Must be within 5 minutes of the server (or in range +/-2h
 706          * in case of Mac OS X), so simply carry over server timestamp
 707          * (as Windows 7 does)
 708          */
 709         rsp_timestamp = find_timestamp(ses);
 710
 711         baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
 712         tilen = ses->auth_key.len;
 713         tiblob = ses->auth_key.response;
 714
 715         ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
 716         if (!ses->auth_key.response) {
 717                 rc = ENOMEM;
 718                 ses->auth_key.len = 0;
 719                 goto setup_ntlmv2_rsp_ret;
 720         }
 721         ses->auth_key.len += baselen;
 722
 723         ntlmv2 = (struct ntlmv2_resp *)
 724                         (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
 725         ntlmv2->blob_signature = cpu_to_le32(0x00000101);
 726         ntlmv2->reserved = 0;
 727         ntlmv2->time = rsp_timestamp;
 728
 729         get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
 730         ntlmv2->reserved2 = 0;
 731
 732         memcpy(ses->auth_key.response + baselen, tiblob, tilen);
 733
 734         rc = crypto_hmacmd5_alloc(ses->server);
 735         if (rc) {
 736                 cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
 737                 goto setup_ntlmv2_rsp_ret;
 738         }
 739
 740         /* calculate ntlmv2_hash */
 741         rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
 742         if (rc) {
 743                 cifs_dbg(VFS, "could not get v2 hash rc %d\n", rc);
 744                 goto setup_ntlmv2_rsp_ret;
 745         }
 746
 747         /* calculate first part of the client response (CR1) */
 748         rc = CalcNTLMv2_response(ses, ntlmv2_hash);
 749         if (rc) {
 750                 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
 751                 goto setup_ntlmv2_rsp_ret;
 752         }
 753
 754         /* now calculate the session key for NTLMv2 */
 755         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
 756                 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
 757         if (rc) {
 758                 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
 759                          __func__);
 760                 goto setup_ntlmv2_rsp_ret;
 761         }
 762
 763         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 764         if (rc) {
 765                 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
 766                 goto setup_ntlmv2_rsp_ret;
 767         }
 768
 769         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 770                 ntlmv2->ntlmv2_hash,
 771                 CIFS_HMAC_MD5_HASH_SIZE);
 772         if (rc) {
 773                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 774                 goto setup_ntlmv2_rsp_ret;
 775         }
 776
 777         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 778                 ses->auth_key.response);
 779         if (rc)
 780                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 781
 782 setup_ntlmv2_rsp_ret:
 783         kfree(tiblob);
 784
 785         return rc;
 786 }
 787
 788 int
 789 calc_seckey(struct cifs_ses *ses)
 790 {
 791         int rc;
 792         struct crypto_blkcipher *tfm_arc4;
 793         struct scatterlist sgin, sgout;
 794         struct blkcipher_desc desc;
 795         unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
 796
 797         get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
 798
 799         tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
 800         if (IS_ERR(tfm_arc4)) {
 801                 rc = PTR_ERR(tfm_arc4);
 802                 cifs_dbg(VFS, "could not allocate crypto API arc4\n");
 803                 return rc;
 804         }
 805
 806         desc.tfm = tfm_arc4;
 807
 808         rc = crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,
 809                                         CIFS_SESS_KEY_SIZE);
 810         if (rc) {
 811                 cifs_dbg(VFS, "%s: Could not set response as a key\n",
 812                          __func__);
 813                 return rc;
 814         }
 815
 816         sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
 817         sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
 818
 819         rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
 820         if (rc) {
 821                 cifs_dbg(VFS, "could not encrypt session key rc: %d\n", rc);
 822                 crypto_free_blkcipher(tfm_arc4);
 823                 return rc;
 824         }
 825
 826         /* make secondary_key/nonce as session key */
 827         memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
 828         /* and make len as that of session key only */
 829         ses->auth_key.len = CIFS_SESS_KEY_SIZE;
 830
 831         crypto_free_blkcipher(tfm_arc4);
 832
 833         return rc;
 834 }
 835
 836 void
 837 cifs_crypto_shash_release(struct TCP_Server_Info *server)
 838 {
 839         if (server->secmech.cmacaes) {
 840                 crypto_free_shash(server->secmech.cmacaes);
 841                 server->secmech.cmacaes = NULL;
 842         }
 843
 844         if (server->secmech.hmacsha256) {
 845                 crypto_free_shash(server->secmech.hmacsha256);
 846                 server->secmech.hmacsha256 = NULL;
 847         }
 848
 849         if (server->secmech.md5) {
 850                 crypto_free_shash(server->secmech.md5);
 851                 server->secmech.md5 = NULL;
 852         }
 853
 854         if (server->secmech.hmacmd5) {
 855                 crypto_free_shash(server->secmech.hmacmd5);
 856                 server->secmech.hmacmd5 = NULL;
 857         }
 858
 859         kfree(server->secmech.sdesccmacaes);
 860         server->secmech.sdesccmacaes = NULL;
 861         kfree(server->secmech.sdeschmacsha256);
 862         server->secmech.sdeschmacsha256 = NULL;
 863         kfree(server->secmech.sdeschmacmd5);
 864         server->secmech.sdeschmacmd5 = NULL;
 865         kfree(server->secmech.sdescmd5);
 866         server->secmech.sdescmd5 = NULL;
 867 }