fs/cifs/cifsencrypt.c

   1 /*
   2  *   fs/cifs/cifsencrypt.c
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2005,2013
   5  *   Author(s): Steve French (sfrench@us.ibm.com)
   6  *
   7  *   This library is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU Lesser General Public License as published
   9  *   by the Free Software Foundation; either version 2.1 of the License, or
  10  *   (at your option) any later version.
  11  *
  12  *   This library is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  15  *   the GNU Lesser General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU Lesser General Public License
  18  *   along with this library; if not, write to the Free Software
  19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21
  22 #include <linux/fs.h>
  23 #include <linux/slab.h>
  24 #include "cifspdu.h"
  25 #include "cifsglob.h"
  26 #include "cifs_debug.h"
  27 #include "cifs_unicode.h"
  28 #include "cifsproto.h"
  29 #include "ntlmssp.h"
  30 #include <linux/ctype.h>
  31 #include <linux/random.h>
  32 #include <linux/highmem.h>
  33
  34 static int
  35 cifs_crypto_shash_md5_allocate(struct TCP_Server_Info *server)
  36 {
  37         int rc;
  38         unsigned int size;
  39
  40         if (server->secmech.sdescmd5 != NULL)
  41                 return 0; /* already allocated */
  42
  43         server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
  44         if (IS_ERR(server->secmech.md5)) {
  45                 cifs_dbg(VFS, "could not allocate crypto md5\n");
  46                 rc = PTR_ERR(server->secmech.md5);
  47                 server->secmech.md5 = NULL;
  48                 return rc;
  49         }
  50
  51         size = sizeof(struct shash_desc) +
  52                         crypto_shash_descsize(server->secmech.md5);
  53         server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
  54         if (!server->secmech.sdescmd5) {
  55                 crypto_free_shash(server->secmech.md5);
  56                 server->secmech.md5 = NULL;
  57                 return -ENOMEM;
  58         }
  59         server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
  60         server->secmech.sdescmd5->shash.flags = 0x0;
  61
  62         return 0;
  63 }
  64
  65 /*
  66  * Calculate and return the CIFS signature based on the mac key and SMB PDU.
  67  * The 16 byte signature must be allocated by the caller. Note we only use the
  68  * 1st eight bytes and that the smb header signature field on input contains
  69  * the sequence number before this function is called. Also, this function
  70  * should be called with the server->srv_mutex held.
  71  */
  72 static int cifs_calc_signature(struct smb_rqst *rqst,
  73                         struct TCP_Server_Info *server, char *signature)
  74 {
  75         int i;
  76         int rc;
  77         struct kvec *iov = rqst->rq_iov;
  78         int n_vec = rqst->rq_nvec;
  79
  80         if (iov == NULL || signature == NULL || server == NULL)
  81                 return -EINVAL;
  82
  83         if (!server->secmech.sdescmd5) {
  84                 rc = cifs_crypto_shash_md5_allocate(server);
  85                 if (rc) {
  86                         cifs_dbg(VFS, "%s: Can't alloc md5 crypto\n", __func__);
  87                         return -1;
  88                 }
  89         }
  90
  91         rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
  92         if (rc) {
  93                 cifs_dbg(VFS, "%s: Could not init md5\n", __func__);
  94                 return rc;
  95         }
  96
  97         rc = crypto_shash_update(&server->secmech.sdescmd5->shash,
  98                 server->session_key.response, server->session_key.len);
  99         if (rc) {
 100                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 101                 return rc;
 102         }
 103
 104         for (i = 0; i < n_vec; i++) {
 105                 if (iov[i].iov_len == 0)
 106                         continue;
 107                 if (iov[i].iov_base == NULL) {
 108                         cifs_dbg(VFS, "null iovec entry\n");
 109                         return -EIO;
 110                 }
 111                 /* The first entry includes a length field (which does not get
 112                    signed that occupies the first 4 bytes before the header */
 113                 if (i == 0) {
 114                         if (iov[0].iov_len <= 8) /* cmd field at offset 9 */
 115                                 break; /* nothing to sign or corrupt header */
 116                         rc =
 117                         crypto_shash_update(&server->secmech.sdescmd5->shash,
 118                                 iov[i].iov_base + 4, iov[i].iov_len - 4);
 119                 } else {
 120                         rc =
 121                         crypto_shash_update(&server->secmech.sdescmd5->shash,
 122                                 iov[i].iov_base, iov[i].iov_len);
 123                 }
 124                 if (rc) {
 125                         cifs_dbg(VFS, "%s: Could not update with payload\n",
 126                                  __func__);
 127                         return rc;
 128                 }
 129         }
 130
 131         /* now hash over the rq_pages array */
 132         for (i = 0; i < rqst->rq_npages; i++) {
 133                 struct kvec p_iov;
 134
 135                 cifs_rqst_page_to_kvec(rqst, i, &p_iov);
 136                 crypto_shash_update(&server->secmech.sdescmd5->shash,
 137                                         p_iov.iov_base, p_iov.iov_len);
 138                 kunmap(rqst->rq_pages[i]);
 139         }
 140
 141         rc = crypto_shash_final(&server->secmech.sdescmd5->shash, signature);
 142         if (rc)
 143                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 144
 145         return rc;
 146 }
 147
 148 /* must be called with server->srv_mutex held */
 149 int cifs_sign_rqst(struct smb_rqst *rqst, struct TCP_Server_Info *server,
 150                    __u32 *pexpected_response_sequence_number)
 151 {
 152         int rc = 0;
 153         char smb_signature[20];
 154         struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
 155
 156         if ((cifs_pdu == NULL) || (server == NULL))
 157                 return -EINVAL;
 158
 159         if (!(cifs_pdu->Flags2 & SMBFLG2_SECURITY_SIGNATURE) ||
 160             server->tcpStatus == CifsNeedNegotiate)
 161                 return rc;
 162
 163         if (!server->session_estab) {
 164                 memcpy(cifs_pdu->Signature.SecuritySignature, "BSRSPYL", 8);
 165                 return rc;
 166         }
 167
 168         cifs_pdu->Signature.Sequence.SequenceNumber =
 169                                 cpu_to_le32(server->sequence_number);
 170         cifs_pdu->Signature.Sequence.Reserved = 0;
 171
 172         *pexpected_response_sequence_number = ++server->sequence_number;
 173         ++server->sequence_number;
 174
 175         rc = cifs_calc_signature(rqst, server, smb_signature);
 176         if (rc)
 177                 memset(cifs_pdu->Signature.SecuritySignature, 0, 8);
 178         else
 179                 memcpy(cifs_pdu->Signature.SecuritySignature, smb_signature, 8);
 180
 181         return rc;
 182 }
 183
 184 int cifs_sign_smbv(struct kvec *iov, int n_vec, struct TCP_Server_Info *server,
 185                    __u32 *pexpected_response_sequence)
 186 {
 187         struct smb_rqst rqst = { .rq_iov = iov,
 188                                  .rq_nvec = n_vec };
 189
 190         return cifs_sign_rqst(&rqst, server, pexpected_response_sequence);
 191 }
 192
 193 /* must be called with server->srv_mutex held */
 194 int cifs_sign_smb(struct smb_hdr *cifs_pdu, struct TCP_Server_Info *server,
 195                   __u32 *pexpected_response_sequence_number)
 196 {
 197         struct kvec iov;
 198
 199         iov.iov_base = cifs_pdu;
 200         iov.iov_len = be32_to_cpu(cifs_pdu->smb_buf_length) + 4;
 201
 202         return cifs_sign_smbv(&iov, 1, server,
 203                               pexpected_response_sequence_number);
 204 }
 205
 206 int cifs_verify_signature(struct smb_rqst *rqst,
 207                           struct TCP_Server_Info *server,
 208                           __u32 expected_sequence_number)
 209 {
 210         unsigned int rc;
 211         char server_response_sig[8];
 212         char what_we_think_sig_should_be[20];
 213         struct smb_hdr *cifs_pdu = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
 214
 215         if (cifs_pdu == NULL || server == NULL)
 216                 return -EINVAL;
 217
 218         if (!server->session_estab)
 219                 return 0;
 220
 221         if (cifs_pdu->Command == SMB_COM_LOCKING_ANDX) {
 222                 struct smb_com_lock_req *pSMB =
 223                         (struct smb_com_lock_req *)cifs_pdu;
 224             if (pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)
 225                         return 0;
 226         }
 227
 228         /* BB what if signatures are supposed to be on for session but
 229            server does not send one? BB */
 230
 231         /* Do not need to verify session setups with signature "BSRSPYL "  */
 232         if (memcmp(cifs_pdu->Signature.SecuritySignature, "BSRSPYL ", 8) == 0)
 233                 cifs_dbg(FYI, "dummy signature received for smb command 0x%x\n",
 234                          cifs_pdu->Command);
 235
 236         /* save off the origiginal signature so we can modify the smb and check
 237                 its signature against what the server sent */
 238         memcpy(server_response_sig, cifs_pdu->Signature.SecuritySignature, 8);
 239
 240         cifs_pdu->Signature.Sequence.SequenceNumber =
 241                                         cpu_to_le32(expected_sequence_number);
 242         cifs_pdu->Signature.Sequence.Reserved = 0;
 243
 244         mutex_lock(&server->srv_mutex);
 245         rc = cifs_calc_signature(rqst, server, what_we_think_sig_should_be);
 246         mutex_unlock(&server->srv_mutex);
 247
 248         if (rc)
 249                 return rc;
 250
 251 /*      cifs_dump_mem("what we think it should be: ",
 252                       what_we_think_sig_should_be, 16); */
 253
 254         if (memcmp(server_response_sig, what_we_think_sig_should_be, 8))
 255                 return -EACCES;
 256         else
 257                 return 0;
 258
 259 }
 260
 261 /* first calculate 24 bytes ntlm response and then 16 byte session key */
 262 int setup_ntlm_response(struct cifs_ses *ses, const struct nls_table *nls_cp)
 263 {
 264         int rc = 0;
 265         unsigned int temp_len = CIFS_SESS_KEY_SIZE + CIFS_AUTH_RESP_SIZE;
 266         char temp_key[CIFS_SESS_KEY_SIZE];
 267
 268         if (!ses)
 269                 return -EINVAL;
 270
 271         ses->auth_key.response = kmalloc(temp_len, GFP_KERNEL);
 272         if (!ses->auth_key.response)
 273                 return -ENOMEM;
 274
 275         ses->auth_key.len = temp_len;
 276
 277         rc = SMBNTencrypt(ses->password, ses->server->cryptkey,
 278                         ses->auth_key.response + CIFS_SESS_KEY_SIZE, nls_cp);
 279         if (rc) {
 280                 cifs_dbg(FYI, "%s Can't generate NTLM response, error: %d\n",
 281                          __func__, rc);
 282                 return rc;
 283         }
 284
 285         rc = E_md4hash(ses->password, temp_key, nls_cp);
 286         if (rc) {
 287                 cifs_dbg(FYI, "%s Can't generate NT hash, error: %d\n",
 288                          __func__, rc);
 289                 return rc;
 290         }
 291
 292         rc = mdfour(ses->auth_key.response, temp_key, CIFS_SESS_KEY_SIZE);
 293         if (rc)
 294                 cifs_dbg(FYI, "%s Can't generate NTLM session key, error: %d\n",
 295                          __func__, rc);
 296
 297         return rc;
 298 }
 299
 300 #ifdef CONFIG_CIFS_WEAK_PW_HASH
 301 int calc_lanman_hash(const char *password, const char *cryptkey, bool encrypt,
 302                         char *lnm_session_key)
 303 {
 304         int i;
 305         int rc;
 306         char password_with_pad[CIFS_ENCPWD_SIZE];
 307
 308         memset(password_with_pad, 0, CIFS_ENCPWD_SIZE);
 309         if (password)
 310                 strncpy(password_with_pad, password, CIFS_ENCPWD_SIZE);
 311
 312         if (!encrypt && global_secflags & CIFSSEC_MAY_PLNTXT) {
 313                 memcpy(lnm_session_key, password_with_pad,
 314                         CIFS_ENCPWD_SIZE);
 315                 return 0;
 316         }
 317
 318         /* calculate old style session key */
 319         /* calling toupper is less broken than repeatedly
 320         calling nls_toupper would be since that will never
 321         work for UTF8, but neither handles multibyte code pages
 322         but the only alternative would be converting to UCS-16 (Unicode)
 323         (using a routine something like UniStrupr) then
 324         uppercasing and then converting back from Unicode - which
 325         would only worth doing it if we knew it were utf8. Basically
 326         utf8 and other multibyte codepages each need their own strupper
 327         function since a byte at a time will ont work. */
 328
 329         for (i = 0; i < CIFS_ENCPWD_SIZE; i++)
 330                 password_with_pad[i] = toupper(password_with_pad[i]);
 331
 332         rc = SMBencrypt(password_with_pad, cryptkey, lnm_session_key);
 333
 334         return rc;
 335 }
 336 #endif /* CIFS_WEAK_PW_HASH */
 337
 338 /* Build a proper attribute value/target info pairs blob.
 339  * Fill in netbios and dns domain name and workstation name
 340  * and client time (total five av pairs and + one end of fields indicator.
 341  * Allocate domain name which gets freed when session struct is deallocated.
 342  */
 343 static int
 344 build_avpair_blob(struct cifs_ses *ses, const struct nls_table *nls_cp)
 345 {
 346         unsigned int dlen;
 347         unsigned int size = 2 * sizeof(struct ntlmssp2_name);
 348         char *defdmname = "WORKGROUP";
 349         unsigned char *blobptr;
 350         struct ntlmssp2_name *attrptr;
 351
 352         if (!ses->domainName) {
 353                 ses->domainName = kstrdup(defdmname, GFP_KERNEL);
 354                 if (!ses->domainName)
 355                         return -ENOMEM;
 356         }
 357
 358         dlen = strlen(ses->domainName);
 359
 360         /*
 361          * The length of this blob is two times the size of a
 362          * structure (av pair) which holds name/size
 363          * ( for NTLMSSP_AV_NB_DOMAIN_NAME followed by NTLMSSP_AV_EOL ) +
 364          * unicode length of a netbios domain name
 365          */
 366         ses->auth_key.len = size + 2 * dlen;
 367         ses->auth_key.response = kzalloc(ses->auth_key.len, GFP_KERNEL);
 368         if (!ses->auth_key.response) {
 369                 ses->auth_key.len = 0;
 370                 return -ENOMEM;
 371         }
 372
 373         blobptr = ses->auth_key.response;
 374         attrptr = (struct ntlmssp2_name *) blobptr;
 375
 376         /*
 377          * As defined in MS-NTLM 3.3.2, just this av pair field
 378          * is sufficient as part of the temp
 379          */
 380         attrptr->type = cpu_to_le16(NTLMSSP_AV_NB_DOMAIN_NAME);
 381         attrptr->length = cpu_to_le16(2 * dlen);
 382         blobptr = (unsigned char *)attrptr + sizeof(struct ntlmssp2_name);
 383         cifs_strtoUTF16((__le16 *)blobptr, ses->domainName, dlen, nls_cp);
 384
 385         return 0;
 386 }
 387
 388 /* Server has provided av pairs/target info in the type 2 challenge
 389  * packet and we have plucked it and stored within smb session.
 390  * We parse that blob here to find netbios domain name to be used
 391  * as part of ntlmv2 authentication (in Target String), if not already
 392  * specified on the command line.
 393  * If this function returns without any error but without fetching
 394  * domain name, authentication may fail against some server but
 395  * may not fail against other (those who are not very particular
 396  * about target string i.e. for some, just user name might suffice.
 397  */
 398 static int
 399 find_domain_name(struct cifs_ses *ses, const struct nls_table *nls_cp)
 400 {
 401         unsigned int attrsize;
 402         unsigned int type;
 403         unsigned int onesize = sizeof(struct ntlmssp2_name);
 404         unsigned char *blobptr;
 405         unsigned char *blobend;
 406         struct ntlmssp2_name *attrptr;
 407
 408         if (!ses->auth_key.len || !ses->auth_key.response)
 409                 return 0;
 410
 411         blobptr = ses->auth_key.response;
 412         blobend = blobptr + ses->auth_key.len;
 413
 414         while (blobptr + onesize < blobend) {
 415                 attrptr = (struct ntlmssp2_name *) blobptr;
 416                 type = le16_to_cpu(attrptr->type);
 417                 if (type == NTLMSSP_AV_EOL)
 418                         break;
 419                 blobptr += 2; /* advance attr type */
 420                 attrsize = le16_to_cpu(attrptr->length);
 421                 blobptr += 2; /* advance attr size */
 422                 if (blobptr + attrsize > blobend)
 423                         break;
 424                 if (type == NTLMSSP_AV_NB_DOMAIN_NAME) {
 425                         if (!attrsize || attrsize >= CIFS_MAX_DOMAINNAME_LEN)
 426                                 break;
 427                         if (!ses->domainName) {
 428                                 ses->domainName =
 429                                         kmalloc(attrsize + 1, GFP_KERNEL);
 430                                 if (!ses->domainName)
 431                                                 return -ENOMEM;
 432                                 cifs_from_utf16(ses->domainName,
 433                                         (__le16 *)blobptr, attrsize, attrsize,
 434                                         nls_cp, false);
 435                                 break;
 436                         }
 437                 }
 438                 blobptr += attrsize; /* advance attr  value */
 439         }
 440
 441         return 0;
 442 }
 443
 444 static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
 445                             const struct nls_table *nls_cp)
 446 {
 447         int rc = 0;
 448         int len;
 449         char nt_hash[CIFS_NTHASH_SIZE];
 450         __le16 *user;
 451         wchar_t *domain;
 452         wchar_t *server;
 453
 454         if (!ses->server->secmech.sdeschmacmd5) {
 455                 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
 456                 return -1;
 457         }
 458
 459         /* calculate md4 hash of password */
 460         E_md4hash(ses->password, nt_hash, nls_cp);
 461
 462         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5, nt_hash,
 463                                 CIFS_NTHASH_SIZE);
 464         if (rc) {
 465                 cifs_dbg(VFS, "%s: Could not set NT Hash as a key\n", __func__);
 466                 return rc;
 467         }
 468
 469         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 470         if (rc) {
 471                 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
 472                 return rc;
 473         }
 474
 475         /* convert ses->user_name to unicode */
 476         len = ses->user_name ? strlen(ses->user_name) : 0;
 477         user = kmalloc(2 + (len * 2), GFP_KERNEL);
 478         if (user == NULL) {
 479                 rc = -ENOMEM;
 480                 return rc;
 481         }
 482
 483         if (len) {
 484                 len = cifs_strtoUTF16(user, ses->user_name, len, nls_cp);
 485                 UniStrupr(user);
 486         } else {
 487                 memset(user, '\0', 2);
 488         }
 489
 490         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 491                                 (char *)user, 2 * len);
 492         kfree(user);
 493         if (rc) {
 494                 cifs_dbg(VFS, "%s: Could not update with user\n", __func__);
 495                 return rc;
 496         }
 497
 498         /* convert ses->domainName to unicode and uppercase */
 499         if (ses->domainName) {
 500                 len = strlen(ses->domainName);
 501
 502                 domain = kmalloc(2 + (len * 2), GFP_KERNEL);
 503                 if (domain == NULL) {
 504                         rc = -ENOMEM;
 505                         return rc;
 506                 }
 507                 len = cifs_strtoUTF16((__le16 *)domain, ses->domainName, len,
 508                                       nls_cp);
 509                 rc =
 510                 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 511                                         (char *)domain, 2 * len);
 512                 kfree(domain);
 513                 if (rc) {
 514                         cifs_dbg(VFS, "%s: Could not update with domain\n",
 515                                  __func__);
 516                         return rc;
 517                 }
 518         } else if (ses->serverName) {
 519                 len = strlen(ses->serverName);
 520
 521                 server = kmalloc(2 + (len * 2), GFP_KERNEL);
 522                 if (server == NULL) {
 523                         rc = -ENOMEM;
 524                         return rc;
 525                 }
 526                 len = cifs_strtoUTF16((__le16 *)server, ses->serverName, len,
 527                                         nls_cp);
 528                 rc =
 529                 crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 530                                         (char *)server, 2 * len);
 531                 kfree(server);
 532                 if (rc) {
 533                         cifs_dbg(VFS, "%s: Could not update with server\n",
 534                                  __func__);
 535                         return rc;
 536                 }
 537         }
 538
 539         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 540                                         ntlmv2_hash);
 541         if (rc)
 542                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 543
 544         return rc;
 545 }
 546
 547 static int
 548 CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
 549 {
 550         int rc;
 551         struct ntlmv2_resp *ntlmv2 = (struct ntlmv2_resp *)
 552             (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
 553         unsigned int hash_len;
 554
 555         /* The MD5 hash starts at challenge_key.key */
 556         hash_len = ses->auth_key.len - (CIFS_SESS_KEY_SIZE +
 557                 offsetof(struct ntlmv2_resp, challenge.key[0]));
 558
 559         if (!ses->server->secmech.sdeschmacmd5) {
 560                 cifs_dbg(VFS, "%s: can't generate ntlmv2 hash\n", __func__);
 561                 return -1;
 562         }
 563
 564         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
 565                                  ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
 566         if (rc) {
 567                 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
 568                          __func__);
 569                 return rc;
 570         }
 571
 572         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 573         if (rc) {
 574                 cifs_dbg(VFS, "%s: could not init hmacmd5\n", __func__);
 575                 return rc;
 576         }
 577
 578         if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED)
 579                 memcpy(ntlmv2->challenge.key,
 580                        ses->ntlmssp->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
 581         else
 582                 memcpy(ntlmv2->challenge.key,
 583                        ses->server->cryptkey, CIFS_SERVER_CHALLENGE_SIZE);
 584         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 585                                  ntlmv2->challenge.key, hash_len);
 586         if (rc) {
 587                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 588                 return rc;
 589         }
 590
 591         /* Note that the MD5 digest over writes anon.challenge_key.key */
 592         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 593                                 ntlmv2->ntlmv2_hash);
 594         if (rc)
 595                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 596
 597         return rc;
 598 }
 599
 600 static int crypto_hmacmd5_alloc(struct TCP_Server_Info *server)
 601 {
 602         int rc;
 603         unsigned int size;
 604
 605         /* check if already allocated */
 606         if (server->secmech.sdeschmacmd5)
 607                 return 0;
 608
 609         server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
 610         if (IS_ERR(server->secmech.hmacmd5)) {
 611                 cifs_dbg(VFS, "could not allocate crypto hmacmd5\n");
 612                 rc = PTR_ERR(server->secmech.hmacmd5);
 613                 server->secmech.hmacmd5 = NULL;
 614                 return rc;
 615         }
 616
 617         size = sizeof(struct shash_desc) +
 618                         crypto_shash_descsize(server->secmech.hmacmd5);
 619         server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
 620         if (!server->secmech.sdeschmacmd5) {
 621                 crypto_free_shash(server->secmech.hmacmd5);
 622                 server->secmech.hmacmd5 = NULL;
 623                 return -ENOMEM;
 624         }
 625         server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
 626         server->secmech.sdeschmacmd5->shash.flags = 0x0;
 627
 628         return 0;
 629 }
 630
 631 int
 632 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 633 {
 634         int rc;
 635         int baselen;
 636         unsigned int tilen;
 637         struct ntlmv2_resp *ntlmv2;
 638         char ntlmv2_hash[16];
 639         unsigned char *tiblob = NULL; /* target info blob */
 640
 641         if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
 642                 if (!ses->domainName) {
 643                         rc = find_domain_name(ses, nls_cp);
 644                         if (rc) {
 645                                 cifs_dbg(VFS, "error %d finding domain name\n",
 646                                          rc);
 647                                 goto setup_ntlmv2_rsp_ret;
 648                         }
 649                 }
 650         } else {
 651                 rc = build_avpair_blob(ses, nls_cp);
 652                 if (rc) {
 653                         cifs_dbg(VFS, "error %d building av pair blob\n", rc);
 654                         goto setup_ntlmv2_rsp_ret;
 655                 }
 656         }
 657
 658         baselen = CIFS_SESS_KEY_SIZE + sizeof(struct ntlmv2_resp);
 659         tilen = ses->auth_key.len;
 660         tiblob = ses->auth_key.response;
 661
 662         ses->auth_key.response = kmalloc(baselen + tilen, GFP_KERNEL);
 663         if (!ses->auth_key.response) {
 664                 rc = ENOMEM;
 665                 ses->auth_key.len = 0;
 666                 goto setup_ntlmv2_rsp_ret;
 667         }
 668         ses->auth_key.len += baselen;
 669
 670         ntlmv2 = (struct ntlmv2_resp *)
 671                         (ses->auth_key.response + CIFS_SESS_KEY_SIZE);
 672         ntlmv2->blob_signature = cpu_to_le32(0x00000101);
 673         ntlmv2->reserved = 0;
 674         /* Must be within 5 minutes of the server */
 675         ntlmv2->time = cpu_to_le64(cifs_UnixTimeToNT(CURRENT_TIME));
 676         get_random_bytes(&ntlmv2->client_chal, sizeof(ntlmv2->client_chal));
 677         ntlmv2->reserved2 = 0;
 678
 679         memcpy(ses->auth_key.response + baselen, tiblob, tilen);
 680
 681         rc = crypto_hmacmd5_alloc(ses->server);
 682         if (rc) {
 683                 cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
 684                 goto setup_ntlmv2_rsp_ret;
 685         }
 686
 687         /* calculate ntlmv2_hash */
 688         rc = calc_ntlmv2_hash(ses, ntlmv2_hash, nls_cp);
 689         if (rc) {
 690                 cifs_dbg(VFS, "could not get v2 hash rc %d\n", rc);
 691                 goto setup_ntlmv2_rsp_ret;
 692         }
 693
 694         /* calculate first part of the client response (CR1) */
 695         rc = CalcNTLMv2_response(ses, ntlmv2_hash);
 696         if (rc) {
 697                 cifs_dbg(VFS, "Could not calculate CR1 rc: %d\n", rc);
 698                 goto setup_ntlmv2_rsp_ret;
 699         }
 700
 701         /* now calculate the session key for NTLMv2 */
 702         rc = crypto_shash_setkey(ses->server->secmech.hmacmd5,
 703                 ntlmv2_hash, CIFS_HMAC_MD5_HASH_SIZE);
 704         if (rc) {
 705                 cifs_dbg(VFS, "%s: Could not set NTLMV2 Hash as a key\n",
 706                          __func__);
 707                 goto setup_ntlmv2_rsp_ret;
 708         }
 709
 710         rc = crypto_shash_init(&ses->server->secmech.sdeschmacmd5->shash);
 711         if (rc) {
 712                 cifs_dbg(VFS, "%s: Could not init hmacmd5\n", __func__);
 713                 goto setup_ntlmv2_rsp_ret;
 714         }
 715
 716         rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,
 717                 ntlmv2->ntlmv2_hash,
 718                 CIFS_HMAC_MD5_HASH_SIZE);
 719         if (rc) {
 720                 cifs_dbg(VFS, "%s: Could not update with response\n", __func__);
 721                 goto setup_ntlmv2_rsp_ret;
 722         }
 723
 724         rc = crypto_shash_final(&ses->server->secmech.sdeschmacmd5->shash,
 725                 ses->auth_key.response);
 726         if (rc)
 727                 cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 728
 729 setup_ntlmv2_rsp_ret:
 730         kfree(tiblob);
 731
 732         return rc;
 733 }
 734
 735 int
 736 calc_seckey(struct cifs_ses *ses)
 737 {
 738         int rc;
 739         struct crypto_blkcipher *tfm_arc4;
 740         struct scatterlist sgin, sgout;
 741         struct blkcipher_desc desc;
 742         unsigned char sec_key[CIFS_SESS_KEY_SIZE]; /* a nonce */
 743
 744         get_random_bytes(sec_key, CIFS_SESS_KEY_SIZE);
 745
 746         tfm_arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC);
 747         if (IS_ERR(tfm_arc4)) {
 748                 rc = PTR_ERR(tfm_arc4);
 749                 cifs_dbg(VFS, "could not allocate crypto API arc4\n");
 750                 return rc;
 751         }
 752
 753         desc.tfm = tfm_arc4;
 754
 755         rc = crypto_blkcipher_setkey(tfm_arc4, ses->auth_key.response,
 756                                         CIFS_SESS_KEY_SIZE);
 757         if (rc) {
 758                 cifs_dbg(VFS, "%s: Could not set response as a key\n",
 759                          __func__);
 760                 return rc;
 761         }
 762
 763         sg_init_one(&sgin, sec_key, CIFS_SESS_KEY_SIZE);
 764         sg_init_one(&sgout, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
 765
 766         rc = crypto_blkcipher_encrypt(&desc, &sgout, &sgin, CIFS_CPHTXT_SIZE);
 767         if (rc) {
 768                 cifs_dbg(VFS, "could not encrypt session key rc: %d\n", rc);
 769                 crypto_free_blkcipher(tfm_arc4);
 770                 return rc;
 771         }
 772
 773         /* make secondary_key/nonce as session key */
 774         memcpy(ses->auth_key.response, sec_key, CIFS_SESS_KEY_SIZE);
 775         /* and make len as that of session key only */
 776         ses->auth_key.len = CIFS_SESS_KEY_SIZE;
 777
 778         crypto_free_blkcipher(tfm_arc4);
 779
 780         return rc;
 781 }
 782
 783 void
 784 cifs_crypto_shash_release(struct TCP_Server_Info *server)
 785 {
 786         if (server->secmech.cmacaes) {
 787                 crypto_free_shash(server->secmech.cmacaes);
 788                 server->secmech.cmacaes = NULL;
 789         }
 790
 791         if (server->secmech.hmacsha256) {
 792                 crypto_free_shash(server->secmech.hmacsha256);
 793                 server->secmech.hmacsha256 = NULL;
 794         }
 795
 796         if (server->secmech.md5) {
 797                 crypto_free_shash(server->secmech.md5);
 798                 server->secmech.md5 = NULL;
 799         }
 800
 801         if (server->secmech.hmacmd5) {
 802                 crypto_free_shash(server->secmech.hmacmd5);
 803                 server->secmech.hmacmd5 = NULL;
 804         }
 805
 806         kfree(server->secmech.sdesccmacaes);
 807         server->secmech.sdesccmacaes = NULL;
 808         kfree(server->secmech.sdeschmacsha256);
 809         server->secmech.sdeschmacsha256 = NULL;
 810         kfree(server->secmech.sdeschmacmd5);
 811         server->secmech.sdeschmacmd5 = NULL;
 812         kfree(server->secmech.sdescmd5);
 813         server->secmech.sdescmd5 = NULL;
 814 }