linux/fs/cifs/sess.c
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   1/*
   2 *   fs/cifs/sess.c
   3 *
   4 *   SMB/CIFS session setup handling routines
   5 *
   6 *   Copyright (c) International Business Machines  Corp., 2006, 2009
   7 *   Author(s): Steve French (sfrench@us.ibm.com)
   8 *
   9 *   This library is free software; you can redistribute it and/or modify
  10 *   it under the terms of the GNU Lesser General Public License as published
  11 *   by the Free Software Foundation; either version 2.1 of the License, or
  12 *   (at your option) any later version.
  13 *
  14 *   This library is distributed in the hope that it will be useful,
  15 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  17 *   the GNU Lesser General Public License for more details.
  18 *
  19 *   You should have received a copy of the GNU Lesser General Public License
  20 *   along with this library; if not, write to the Free Software
  21 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22 */
  23
  24#include "cifspdu.h"
  25#include "cifsglob.h"
  26#include "cifsproto.h"
  27#include "cifs_unicode.h"
  28#include "cifs_debug.h"
  29#include "ntlmssp.h"
  30#include "nterr.h"
  31#include <linux/utsname.h>
  32#include <linux/slab.h>
  33#include "cifs_spnego.h"
  34
  35/*
  36 * Checks if this is the first smb session to be reconnected after
  37 * the socket has been reestablished (so we know whether to use vc 0).
  38 * Called while holding the cifs_tcp_ses_lock, so do not block
  39 */
  40static bool is_first_ses_reconnect(struct cifsSesInfo *ses)
  41{
  42        struct list_head *tmp;
  43        struct cifsSesInfo *tmp_ses;
  44
  45        list_for_each(tmp, &ses->server->smb_ses_list) {
  46                tmp_ses = list_entry(tmp, struct cifsSesInfo,
  47                                     smb_ses_list);
  48                if (tmp_ses->need_reconnect == false)
  49                        return false;
  50        }
  51        /* could not find a session that was already connected,
  52           this must be the first one we are reconnecting */
  53        return true;
  54}
  55
  56/*
  57 *      vc number 0 is treated specially by some servers, and should be the
  58 *      first one we request.  After that we can use vcnumbers up to maxvcs,
  59 *      one for each smb session (some Windows versions set maxvcs incorrectly
  60 *      so maxvc=1 can be ignored).  If we have too many vcs, we can reuse
  61 *      any vc but zero (some servers reset the connection on vcnum zero)
  62 *
  63 */
  64static __le16 get_next_vcnum(struct cifsSesInfo *ses)
  65{
  66        __u16 vcnum = 0;
  67        struct list_head *tmp;
  68        struct cifsSesInfo *tmp_ses;
  69        __u16 max_vcs = ses->server->max_vcs;
  70        __u16 i;
  71        int free_vc_found = 0;
  72
  73        /* Quoting the MS-SMB specification: "Windows-based SMB servers set this
  74        field to one but do not enforce this limit, which allows an SMB client
  75        to establish more virtual circuits than allowed by this value ... but
  76        other server implementations can enforce this limit." */
  77        if (max_vcs < 2)
  78                max_vcs = 0xFFFF;
  79
  80        spin_lock(&cifs_tcp_ses_lock);
  81        if ((ses->need_reconnect) && is_first_ses_reconnect(ses))
  82                        goto get_vc_num_exit;  /* vcnum will be zero */
  83        for (i = ses->server->srv_count - 1; i < max_vcs; i++) {
  84                if (i == 0) /* this is the only connection, use vc 0 */
  85                        break;
  86
  87                free_vc_found = 1;
  88
  89                list_for_each(tmp, &ses->server->smb_ses_list) {
  90                        tmp_ses = list_entry(tmp, struct cifsSesInfo,
  91                                             smb_ses_list);
  92                        if (tmp_ses->vcnum == i) {
  93                                free_vc_found = 0;
  94                                break; /* found duplicate, try next vcnum */
  95                        }
  96                }
  97                if (free_vc_found)
  98                        break; /* we found a vcnumber that will work - use it */
  99        }
 100
 101        if (i == 0)
 102                vcnum = 0; /* for most common case, ie if one smb session, use
 103                              vc zero.  Also for case when no free vcnum, zero
 104                              is safest to send (some clients only send zero) */
 105        else if (free_vc_found == 0)
 106                vcnum = 1;  /* we can not reuse vc=0 safely, since some servers
 107                                reset all uids on that, but 1 is ok. */
 108        else
 109                vcnum = i;
 110        ses->vcnum = vcnum;
 111get_vc_num_exit:
 112        spin_unlock(&cifs_tcp_ses_lock);
 113
 114        return cpu_to_le16(vcnum);
 115}
 116
 117static __u32 cifs_ssetup_hdr(struct cifsSesInfo *ses, SESSION_SETUP_ANDX *pSMB)
 118{
 119        __u32 capabilities = 0;
 120
 121        /* init fields common to all four types of SessSetup */
 122        /* Note that offsets for first seven fields in req struct are same  */
 123        /*      in CIFS Specs so does not matter which of 3 forms of struct */
 124        /*      that we use in next few lines                               */
 125        /* Note that header is initialized to zero in header_assemble */
 126        pSMB->req.AndXCommand = 0xFF;
 127        pSMB->req.MaxBufferSize = cpu_to_le16(ses->server->maxBuf);
 128        pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);
 129        pSMB->req.VcNumber = get_next_vcnum(ses);
 130
 131        /* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
 132
 133        /* BB verify whether signing required on neg or just on auth frame
 134           (and NTLM case) */
 135
 136        capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
 137                        CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
 138
 139        if (ses->server->secMode &
 140            (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
 141                pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
 142
 143        if (ses->capabilities & CAP_UNICODE) {
 144                pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
 145                capabilities |= CAP_UNICODE;
 146        }
 147        if (ses->capabilities & CAP_STATUS32) {
 148                pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
 149                capabilities |= CAP_STATUS32;
 150        }
 151        if (ses->capabilities & CAP_DFS) {
 152                pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
 153                capabilities |= CAP_DFS;
 154        }
 155        if (ses->capabilities & CAP_UNIX)
 156                capabilities |= CAP_UNIX;
 157
 158        return capabilities;
 159}
 160
 161static void
 162unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
 163{
 164        char *bcc_ptr = *pbcc_area;
 165        int bytes_ret = 0;
 166
 167        /* Copy OS version */
 168        bytes_ret = cifs_strtoUCS((__le16 *)bcc_ptr, "Linux version ", 32,
 169                                  nls_cp);
 170        bcc_ptr += 2 * bytes_ret;
 171        bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, init_utsname()->release,
 172                                  32, nls_cp);
 173        bcc_ptr += 2 * bytes_ret;
 174        bcc_ptr += 2; /* trailing null */
 175
 176        bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
 177                                  32, nls_cp);
 178        bcc_ptr += 2 * bytes_ret;
 179        bcc_ptr += 2; /* trailing null */
 180
 181        *pbcc_area = bcc_ptr;
 182}
 183
 184static void unicode_domain_string(char **pbcc_area, struct cifsSesInfo *ses,
 185                                   const struct nls_table *nls_cp)
 186{
 187        char *bcc_ptr = *pbcc_area;
 188        int bytes_ret = 0;
 189
 190        /* copy domain */
 191        if (ses->domainName == NULL) {
 192                /* Sending null domain better than using a bogus domain name (as
 193                we did briefly in 2.6.18) since server will use its default */
 194                *bcc_ptr = 0;
 195                *(bcc_ptr+1) = 0;
 196                bytes_ret = 0;
 197        } else
 198                bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->domainName,
 199                                          256, nls_cp);
 200        bcc_ptr += 2 * bytes_ret;
 201        bcc_ptr += 2;  /* account for null terminator */
 202
 203        *pbcc_area = bcc_ptr;
 204}
 205
 206
 207static void unicode_ssetup_strings(char **pbcc_area, struct cifsSesInfo *ses,
 208                                   const struct nls_table *nls_cp)
 209{
 210        char *bcc_ptr = *pbcc_area;
 211        int bytes_ret = 0;
 212
 213        /* BB FIXME add check that strings total less
 214        than 335 or will need to send them as arrays */
 215
 216        /* unicode strings, must be word aligned before the call */
 217/*      if ((long) bcc_ptr % 2) {
 218                *bcc_ptr = 0;
 219                bcc_ptr++;
 220        } */
 221        /* copy user */
 222        if (ses->user_name == NULL) {
 223                /* null user mount */
 224                *bcc_ptr = 0;
 225                *(bcc_ptr+1) = 0;
 226        } else {
 227                bytes_ret = cifs_strtoUCS((__le16 *) bcc_ptr, ses->user_name,
 228                                          MAX_USERNAME_SIZE, nls_cp);
 229        }
 230        bcc_ptr += 2 * bytes_ret;
 231        bcc_ptr += 2; /* account for null termination */
 232
 233        unicode_domain_string(&bcc_ptr, ses, nls_cp);
 234        unicode_oslm_strings(&bcc_ptr, nls_cp);
 235
 236        *pbcc_area = bcc_ptr;
 237}
 238
 239static void ascii_ssetup_strings(char **pbcc_area, struct cifsSesInfo *ses,
 240                                 const struct nls_table *nls_cp)
 241{
 242        char *bcc_ptr = *pbcc_area;
 243
 244        /* copy user */
 245        /* BB what about null user mounts - check that we do this BB */
 246        /* copy user */
 247        if (ses->user_name != NULL)
 248                strncpy(bcc_ptr, ses->user_name, MAX_USERNAME_SIZE);
 249        /* else null user mount */
 250
 251        bcc_ptr += strnlen(ses->user_name, MAX_USERNAME_SIZE);
 252        *bcc_ptr = 0;
 253        bcc_ptr++; /* account for null termination */
 254
 255        /* copy domain */
 256
 257        if (ses->domainName != NULL) {
 258                strncpy(bcc_ptr, ses->domainName, 256);
 259                bcc_ptr += strnlen(ses->domainName, 256);
 260        } /* else we will send a null domain name
 261             so the server will default to its own domain */
 262        *bcc_ptr = 0;
 263        bcc_ptr++;
 264
 265        /* BB check for overflow here */
 266
 267        strcpy(bcc_ptr, "Linux version ");
 268        bcc_ptr += strlen("Linux version ");
 269        strcpy(bcc_ptr, init_utsname()->release);
 270        bcc_ptr += strlen(init_utsname()->release) + 1;
 271
 272        strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
 273        bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
 274
 275        *pbcc_area = bcc_ptr;
 276}
 277
 278static void
 279decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifsSesInfo *ses,
 280                      const struct nls_table *nls_cp)
 281{
 282        int len;
 283        char *data = *pbcc_area;
 284
 285        cFYI(1, "bleft %d", bleft);
 286
 287        kfree(ses->serverOS);
 288        ses->serverOS = cifs_strndup_from_ucs(data, bleft, true, nls_cp);
 289        cFYI(1, "serverOS=%s", ses->serverOS);
 290        len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
 291        data += len;
 292        bleft -= len;
 293        if (bleft <= 0)
 294                return;
 295
 296        kfree(ses->serverNOS);
 297        ses->serverNOS = cifs_strndup_from_ucs(data, bleft, true, nls_cp);
 298        cFYI(1, "serverNOS=%s", ses->serverNOS);
 299        len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
 300        data += len;
 301        bleft -= len;
 302        if (bleft <= 0)
 303                return;
 304
 305        kfree(ses->serverDomain);
 306        ses->serverDomain = cifs_strndup_from_ucs(data, bleft, true, nls_cp);
 307        cFYI(1, "serverDomain=%s", ses->serverDomain);
 308
 309        return;
 310}
 311
 312static int decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
 313                               struct cifsSesInfo *ses,
 314                               const struct nls_table *nls_cp)
 315{
 316        int rc = 0;
 317        int len;
 318        char *bcc_ptr = *pbcc_area;
 319
 320        cFYI(1, "decode sessetup ascii. bleft %d", bleft);
 321
 322        len = strnlen(bcc_ptr, bleft);
 323        if (len >= bleft)
 324                return rc;
 325
 326        kfree(ses->serverOS);
 327
 328        ses->serverOS = kzalloc(len + 1, GFP_KERNEL);
 329        if (ses->serverOS)
 330                strncpy(ses->serverOS, bcc_ptr, len);
 331        if (strncmp(ses->serverOS, "OS/2", 4) == 0) {
 332                        cFYI(1, "OS/2 server");
 333                        ses->flags |= CIFS_SES_OS2;
 334        }
 335
 336        bcc_ptr += len + 1;
 337        bleft -= len + 1;
 338
 339        len = strnlen(bcc_ptr, bleft);
 340        if (len >= bleft)
 341                return rc;
 342
 343        kfree(ses->serverNOS);
 344
 345        ses->serverNOS = kzalloc(len + 1, GFP_KERNEL);
 346        if (ses->serverNOS)
 347                strncpy(ses->serverNOS, bcc_ptr, len);
 348
 349        bcc_ptr += len + 1;
 350        bleft -= len + 1;
 351
 352        len = strnlen(bcc_ptr, bleft);
 353        if (len > bleft)
 354                return rc;
 355
 356        /* No domain field in LANMAN case. Domain is
 357           returned by old servers in the SMB negprot response */
 358        /* BB For newer servers which do not support Unicode,
 359           but thus do return domain here we could add parsing
 360           for it later, but it is not very important */
 361        cFYI(1, "ascii: bytes left %d", bleft);
 362
 363        return rc;
 364}
 365
 366static int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
 367                                    struct cifsSesInfo *ses)
 368{
 369        unsigned int tioffset; /* challenge message target info area */
 370        unsigned int tilen; /* challenge message target info area length  */
 371
 372        CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
 373
 374        if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
 375                cERROR(1, "challenge blob len %d too small", blob_len);
 376                return -EINVAL;
 377        }
 378
 379        if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
 380                cERROR(1, "blob signature incorrect %s", pblob->Signature);
 381                return -EINVAL;
 382        }
 383        if (pblob->MessageType != NtLmChallenge) {
 384                cERROR(1, "Incorrect message type %d", pblob->MessageType);
 385                return -EINVAL;
 386        }
 387
 388        memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
 389        /* BB we could decode pblob->NegotiateFlags; some may be useful */
 390        /* In particular we can examine sign flags */
 391        /* BB spec says that if AvId field of MsvAvTimestamp is populated then
 392                we must set the MIC field of the AUTHENTICATE_MESSAGE */
 393        ses->ntlmssp->server_flags = le32_to_cpu(pblob->NegotiateFlags);
 394        tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
 395        tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
 396        if (tilen) {
 397                ses->auth_key.response = kmalloc(tilen, GFP_KERNEL);
 398                if (!ses->auth_key.response) {
 399                        cERROR(1, "Challenge target info allocation failure");
 400                        return -ENOMEM;
 401                }
 402                memcpy(ses->auth_key.response, bcc_ptr + tioffset, tilen);
 403                ses->auth_key.len = tilen;
 404        }
 405
 406        return 0;
 407}
 408
 409/* BB Move to ntlmssp.c eventually */
 410
 411/* We do not malloc the blob, it is passed in pbuffer, because
 412   it is fixed size, and small, making this approach cleaner */
 413static void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
 414                                         struct cifsSesInfo *ses)
 415{
 416        NEGOTIATE_MESSAGE *sec_blob = (NEGOTIATE_MESSAGE *)pbuffer;
 417        __u32 flags;
 418
 419        memset(pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
 420        memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
 421        sec_blob->MessageType = NtLmNegotiate;
 422
 423        /* BB is NTLMV2 session security format easier to use here? */
 424        flags = NTLMSSP_NEGOTIATE_56 |  NTLMSSP_REQUEST_TARGET |
 425                NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
 426                NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
 427        if (ses->server->secMode &
 428                        (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
 429                flags |= NTLMSSP_NEGOTIATE_SIGN;
 430                if (!ses->server->session_estab)
 431                        flags |= NTLMSSP_NEGOTIATE_KEY_XCH |
 432                                NTLMSSP_NEGOTIATE_EXTENDED_SEC;
 433        }
 434
 435        sec_blob->NegotiateFlags = cpu_to_le32(flags);
 436
 437        sec_blob->WorkstationName.BufferOffset = 0;
 438        sec_blob->WorkstationName.Length = 0;
 439        sec_blob->WorkstationName.MaximumLength = 0;
 440
 441        /* Domain name is sent on the Challenge not Negotiate NTLMSSP request */
 442        sec_blob->DomainName.BufferOffset = 0;
 443        sec_blob->DomainName.Length = 0;
 444        sec_blob->DomainName.MaximumLength = 0;
 445}
 446
 447/* We do not malloc the blob, it is passed in pbuffer, because its
 448   maximum possible size is fixed and small, making this approach cleaner.
 449   This function returns the length of the data in the blob */
 450static int build_ntlmssp_auth_blob(unsigned char *pbuffer,
 451                                        u16 *buflen,
 452                                   struct cifsSesInfo *ses,
 453                                   const struct nls_table *nls_cp)
 454{
 455        int rc;
 456        AUTHENTICATE_MESSAGE *sec_blob = (AUTHENTICATE_MESSAGE *)pbuffer;
 457        __u32 flags;
 458        unsigned char *tmp;
 459
 460        memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
 461        sec_blob->MessageType = NtLmAuthenticate;
 462
 463        flags = NTLMSSP_NEGOTIATE_56 |
 464                NTLMSSP_REQUEST_TARGET | NTLMSSP_NEGOTIATE_TARGET_INFO |
 465                NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
 466                NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
 467        if (ses->server->secMode &
 468           (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
 469                flags |= NTLMSSP_NEGOTIATE_SIGN;
 470        if (ses->server->secMode & SECMODE_SIGN_REQUIRED)
 471                flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
 472
 473        tmp = pbuffer + sizeof(AUTHENTICATE_MESSAGE);
 474        sec_blob->NegotiateFlags = cpu_to_le32(flags);
 475
 476        sec_blob->LmChallengeResponse.BufferOffset =
 477                                cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
 478        sec_blob->LmChallengeResponse.Length = 0;
 479        sec_blob->LmChallengeResponse.MaximumLength = 0;
 480
 481        sec_blob->NtChallengeResponse.BufferOffset = cpu_to_le32(tmp - pbuffer);
 482        rc = setup_ntlmv2_rsp(ses, nls_cp);
 483        if (rc) {
 484                cERROR(1, "Error %d during NTLMSSP authentication", rc);
 485                goto setup_ntlmv2_ret;
 486        }
 487        memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
 488                        ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 489        tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
 490
 491        sec_blob->NtChallengeResponse.Length =
 492                        cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 493        sec_blob->NtChallengeResponse.MaximumLength =
 494                        cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 495
 496        if (ses->domainName == NULL) {
 497                sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 498                sec_blob->DomainName.Length = 0;
 499                sec_blob->DomainName.MaximumLength = 0;
 500                tmp += 2;
 501        } else {
 502                int len;
 503                len = cifs_strtoUCS((__le16 *)tmp, ses->domainName,
 504                                    MAX_USERNAME_SIZE, nls_cp);
 505                len *= 2; /* unicode is 2 bytes each */
 506                sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 507                sec_blob->DomainName.Length = cpu_to_le16(len);
 508                sec_blob->DomainName.MaximumLength = cpu_to_le16(len);
 509                tmp += len;
 510        }
 511
 512        if (ses->user_name == NULL) {
 513                sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 514                sec_blob->UserName.Length = 0;
 515                sec_blob->UserName.MaximumLength = 0;
 516                tmp += 2;
 517        } else {
 518                int len;
 519                len = cifs_strtoUCS((__le16 *)tmp, ses->user_name,
 520                                    MAX_USERNAME_SIZE, nls_cp);
 521                len *= 2; /* unicode is 2 bytes each */
 522                sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 523                sec_blob->UserName.Length = cpu_to_le16(len);
 524                sec_blob->UserName.MaximumLength = cpu_to_le16(len);
 525                tmp += len;
 526        }
 527
 528        sec_blob->WorkstationName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 529        sec_blob->WorkstationName.Length = 0;
 530        sec_blob->WorkstationName.MaximumLength = 0;
 531        tmp += 2;
 532
 533        if (((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) ||
 534                (ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC))
 535                        && !calc_seckey(ses)) {
 536                memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
 537                sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
 538                sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
 539                sec_blob->SessionKey.MaximumLength =
 540                                cpu_to_le16(CIFS_CPHTXT_SIZE);
 541                tmp += CIFS_CPHTXT_SIZE;
 542        } else {
 543                sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
 544                sec_blob->SessionKey.Length = 0;
 545                sec_blob->SessionKey.MaximumLength = 0;
 546        }
 547
 548setup_ntlmv2_ret:
 549        *buflen = tmp - pbuffer;
 550        return rc;
 551}
 552
 553int
 554CIFS_SessSetup(unsigned int xid, struct cifsSesInfo *ses,
 555               const struct nls_table *nls_cp)
 556{
 557        int rc = 0;
 558        int wct;
 559        struct smb_hdr *smb_buf;
 560        char *bcc_ptr;
 561        char *str_area;
 562        SESSION_SETUP_ANDX *pSMB;
 563        __u32 capabilities;
 564        __u16 count;
 565        int resp_buf_type;
 566        struct kvec iov[3];
 567        enum securityEnum type;
 568        __u16 action, bytes_remaining;
 569        struct key *spnego_key = NULL;
 570        __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
 571        u16 blob_len;
 572        char *ntlmsspblob = NULL;
 573
 574        if (ses == NULL)
 575                return -EINVAL;
 576
 577        type = ses->server->secType;
 578        cFYI(1, "sess setup type %d", type);
 579        if (type == RawNTLMSSP) {
 580                /* if memory allocation is successful, caller of this function
 581                 * frees it.
 582                 */
 583                ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
 584                if (!ses->ntlmssp)
 585                        return -ENOMEM;
 586        }
 587
 588ssetup_ntlmssp_authenticate:
 589        if (phase == NtLmChallenge)
 590                phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
 591
 592        if (type == LANMAN) {
 593#ifndef CONFIG_CIFS_WEAK_PW_HASH
 594                /* LANMAN and plaintext are less secure and off by default.
 595                So we make this explicitly be turned on in kconfig (in the
 596                build) and turned on at runtime (changed from the default)
 597                in proc/fs/cifs or via mount parm.  Unfortunately this is
 598                needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
 599                return -EOPNOTSUPP;
 600#endif
 601                wct = 10; /* lanman 2 style sessionsetup */
 602        } else if ((type == NTLM) || (type == NTLMv2)) {
 603                /* For NTLMv2 failures eventually may need to retry NTLM */
 604                wct = 13; /* old style NTLM sessionsetup */
 605        } else /* same size: negotiate or auth, NTLMSSP or extended security */
 606                wct = 12;
 607
 608        rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
 609                            (void **)&smb_buf);
 610        if (rc)
 611                return rc;
 612
 613        pSMB = (SESSION_SETUP_ANDX *)smb_buf;
 614
 615        capabilities = cifs_ssetup_hdr(ses, pSMB);
 616
 617        /* we will send the SMB in three pieces:
 618        a fixed length beginning part, an optional
 619        SPNEGO blob (which can be zero length), and a
 620        last part which will include the strings
 621        and rest of bcc area. This allows us to avoid
 622        a large buffer 17K allocation */
 623        iov[0].iov_base = (char *)pSMB;
 624        iov[0].iov_len = smb_buf->smb_buf_length + 4;
 625
 626        /* setting this here allows the code at the end of the function
 627           to free the request buffer if there's an error */
 628        resp_buf_type = CIFS_SMALL_BUFFER;
 629
 630        /* 2000 big enough to fit max user, domain, NOS name etc. */
 631        str_area = kmalloc(2000, GFP_KERNEL);
 632        if (str_area == NULL) {
 633                rc = -ENOMEM;
 634                goto ssetup_exit;
 635        }
 636        bcc_ptr = str_area;
 637
 638        ses->flags &= ~CIFS_SES_LANMAN;
 639
 640        iov[1].iov_base = NULL;
 641        iov[1].iov_len = 0;
 642
 643        if (type == LANMAN) {
 644#ifdef CONFIG_CIFS_WEAK_PW_HASH
 645                char lnm_session_key[CIFS_AUTH_RESP_SIZE];
 646
 647                pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
 648
 649                /* no capabilities flags in old lanman negotiation */
 650
 651                pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
 652
 653                /* Calculate hash with password and copy into bcc_ptr.
 654                 * Encryption Key (stored as in cryptkey) gets used if the
 655                 * security mode bit in Negottiate Protocol response states
 656                 * to use challenge/response method (i.e. Password bit is 1).
 657                 */
 658
 659                calc_lanman_hash(ses->password, ses->server->cryptkey,
 660                                 ses->server->secMode & SECMODE_PW_ENCRYPT ?
 661                                        true : false, lnm_session_key);
 662
 663                ses->flags |= CIFS_SES_LANMAN;
 664                memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
 665                bcc_ptr += CIFS_AUTH_RESP_SIZE;
 666
 667                /* can not sign if LANMAN negotiated so no need
 668                to calculate signing key? but what if server
 669                changed to do higher than lanman dialect and
 670                we reconnected would we ever calc signing_key? */
 671
 672                cFYI(1, "Negotiating LANMAN setting up strings");
 673                /* Unicode not allowed for LANMAN dialects */
 674                ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
 675#endif
 676        } else if (type == NTLM) {
 677                pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
 678                pSMB->req_no_secext.CaseInsensitivePasswordLength =
 679                        cpu_to_le16(CIFS_AUTH_RESP_SIZE);
 680                pSMB->req_no_secext.CaseSensitivePasswordLength =
 681                        cpu_to_le16(CIFS_AUTH_RESP_SIZE);
 682
 683                /* calculate ntlm response and session key */
 684                rc = setup_ntlm_response(ses);
 685                if (rc) {
 686                        cERROR(1, "Error %d during NTLM authentication", rc);
 687                        goto ssetup_exit;
 688                }
 689
 690                /* copy ntlm response */
 691                memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
 692                                CIFS_AUTH_RESP_SIZE);
 693                bcc_ptr += CIFS_AUTH_RESP_SIZE;
 694                memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
 695                                CIFS_AUTH_RESP_SIZE);
 696                bcc_ptr += CIFS_AUTH_RESP_SIZE;
 697
 698                if (ses->capabilities & CAP_UNICODE) {
 699                        /* unicode strings must be word aligned */
 700                        if (iov[0].iov_len % 2) {
 701                                *bcc_ptr = 0;
 702                                bcc_ptr++;
 703                        }
 704                        unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
 705                } else
 706                        ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
 707        } else if (type == NTLMv2) {
 708                pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
 709
 710                /* LM2 password would be here if we supported it */
 711                pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
 712
 713                /* calculate nlmv2 response and session key */
 714                rc = setup_ntlmv2_rsp(ses, nls_cp);
 715                if (rc) {
 716                        cERROR(1, "Error %d during NTLMv2 authentication", rc);
 717                        goto ssetup_exit;
 718                }
 719                memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
 720                                ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 721                bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
 722
 723                /* set case sensitive password length after tilen may get
 724                 * assigned, tilen is 0 otherwise.
 725                 */
 726                pSMB->req_no_secext.CaseSensitivePasswordLength =
 727                        cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 728
 729                if (ses->capabilities & CAP_UNICODE) {
 730                        if (iov[0].iov_len % 2) {
 731                                *bcc_ptr = 0;
 732                                bcc_ptr++;
 733                        }
 734                        unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
 735                } else
 736                        ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
 737        } else if (type == Kerberos) {
 738#ifdef CONFIG_CIFS_UPCALL
 739                struct cifs_spnego_msg *msg;
 740
 741                spnego_key = cifs_get_spnego_key(ses);
 742                if (IS_ERR(spnego_key)) {
 743                        rc = PTR_ERR(spnego_key);
 744                        spnego_key = NULL;
 745                        goto ssetup_exit;
 746                }
 747
 748                msg = spnego_key->payload.data;
 749                /* check version field to make sure that cifs.upcall is
 750                   sending us a response in an expected form */
 751                if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
 752                        cERROR(1, "incorrect version of cifs.upcall (expected"
 753                                   " %d but got %d)",
 754                                   CIFS_SPNEGO_UPCALL_VERSION, msg->version);
 755                        rc = -EKEYREJECTED;
 756                        goto ssetup_exit;
 757                }
 758
 759                ses->auth_key.response = kmalloc(msg->sesskey_len, GFP_KERNEL);
 760                if (!ses->auth_key.response) {
 761                        cERROR(1, "Kerberos can't allocate (%u bytes) memory",
 762                                        msg->sesskey_len);
 763                        rc = -ENOMEM;
 764                        goto ssetup_exit;
 765                }
 766                memcpy(ses->auth_key.response, msg->data, msg->sesskey_len);
 767                ses->auth_key.len = msg->sesskey_len;
 768
 769                pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
 770                capabilities |= CAP_EXTENDED_SECURITY;
 771                pSMB->req.Capabilities = cpu_to_le32(capabilities);
 772                iov[1].iov_base = msg->data + msg->sesskey_len;
 773                iov[1].iov_len = msg->secblob_len;
 774                pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
 775
 776                if (ses->capabilities & CAP_UNICODE) {
 777                        /* unicode strings must be word aligned */
 778                        if ((iov[0].iov_len + iov[1].iov_len) % 2) {
 779                                *bcc_ptr = 0;
 780                                bcc_ptr++;
 781                        }
 782                        unicode_oslm_strings(&bcc_ptr, nls_cp);
 783                        unicode_domain_string(&bcc_ptr, ses, nls_cp);
 784                } else
 785                /* BB: is this right? */
 786                        ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
 787#else /* ! CONFIG_CIFS_UPCALL */
 788                cERROR(1, "Kerberos negotiated but upcall support disabled!");
 789                rc = -ENOSYS;
 790                goto ssetup_exit;
 791#endif /* CONFIG_CIFS_UPCALL */
 792        } else if (type == RawNTLMSSP) {
 793                if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
 794                        cERROR(1, "NTLMSSP requires Unicode support");
 795                        rc = -ENOSYS;
 796                        goto ssetup_exit;
 797                }
 798
 799                cFYI(1, "ntlmssp session setup phase %d", phase);
 800                pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
 801                capabilities |= CAP_EXTENDED_SECURITY;
 802                pSMB->req.Capabilities |= cpu_to_le32(capabilities);
 803                switch(phase) {
 804                case NtLmNegotiate:
 805                        build_ntlmssp_negotiate_blob(
 806                                pSMB->req.SecurityBlob, ses);
 807                        iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
 808                        iov[1].iov_base = pSMB->req.SecurityBlob;
 809                        pSMB->req.SecurityBlobLength =
 810                                cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
 811                        break;
 812                case NtLmAuthenticate:
 813                        /*
 814                         * 5 is an empirical value, large enough to hold
 815                         * authenticate message plus max 10 of av paris,
 816                         * domain, user, workstation names, flags, etc.
 817                         */
 818                        ntlmsspblob = kzalloc(
 819                                5*sizeof(struct _AUTHENTICATE_MESSAGE),
 820                                GFP_KERNEL);
 821                        if (!ntlmsspblob) {
 822                                cERROR(1, "Can't allocate NTLMSSP blob");
 823                                rc = -ENOMEM;
 824                                goto ssetup_exit;
 825                        }
 826
 827                        rc = build_ntlmssp_auth_blob(ntlmsspblob,
 828                                                &blob_len, ses, nls_cp);
 829                        if (rc)
 830                                goto ssetup_exit;
 831                        iov[1].iov_len = blob_len;
 832                        iov[1].iov_base = ntlmsspblob;
 833                        pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
 834                        /*
 835                         * Make sure that we tell the server that we are using
 836                         * the uid that it just gave us back on the response
 837                         * (challenge)
 838                         */
 839                        smb_buf->Uid = ses->Suid;
 840                        break;
 841                default:
 842                        cERROR(1, "invalid phase %d", phase);
 843                        rc = -ENOSYS;
 844                        goto ssetup_exit;
 845                }
 846                /* unicode strings must be word aligned */
 847                if ((iov[0].iov_len + iov[1].iov_len) % 2) {
 848                        *bcc_ptr = 0;
 849                        bcc_ptr++;
 850                }
 851                unicode_oslm_strings(&bcc_ptr, nls_cp);
 852        } else {
 853                cERROR(1, "secType %d not supported!", type);
 854                rc = -ENOSYS;
 855                goto ssetup_exit;
 856        }
 857
 858        iov[2].iov_base = str_area;
 859        iov[2].iov_len = (long) bcc_ptr - (long) str_area;
 860
 861        count = iov[1].iov_len + iov[2].iov_len;
 862        smb_buf->smb_buf_length += count;
 863
 864        put_bcc_le(count, smb_buf);
 865
 866        rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
 867                          CIFS_LOG_ERROR);
 868        /* SMB request buf freed in SendReceive2 */
 869
 870        pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
 871        smb_buf = (struct smb_hdr *)iov[0].iov_base;
 872
 873        if ((type == RawNTLMSSP) && (smb_buf->Status.CifsError ==
 874                        cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))) {
 875                if (phase != NtLmNegotiate) {
 876                        cERROR(1, "Unexpected more processing error");
 877                        goto ssetup_exit;
 878                }
 879                /* NTLMSSP Negotiate sent now processing challenge (response) */
 880                phase = NtLmChallenge; /* process ntlmssp challenge */
 881                rc = 0; /* MORE_PROC rc is not an error here, but expected */
 882        }
 883        if (rc)
 884                goto ssetup_exit;
 885
 886        if ((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
 887                rc = -EIO;
 888                cERROR(1, "bad word count %d", smb_buf->WordCount);
 889                goto ssetup_exit;
 890        }
 891        action = le16_to_cpu(pSMB->resp.Action);
 892        if (action & GUEST_LOGIN)
 893                cFYI(1, "Guest login"); /* BB mark SesInfo struct? */
 894        ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
 895        cFYI(1, "UID = %d ", ses->Suid);
 896        /* response can have either 3 or 4 word count - Samba sends 3 */
 897        /* and lanman response is 3 */
 898        bytes_remaining = get_bcc(smb_buf);
 899        bcc_ptr = pByteArea(smb_buf);
 900
 901        if (smb_buf->WordCount == 4) {
 902                blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
 903                if (blob_len > bytes_remaining) {
 904                        cERROR(1, "bad security blob length %d", blob_len);
 905                        rc = -EINVAL;
 906                        goto ssetup_exit;
 907                }
 908                if (phase == NtLmChallenge) {
 909                        rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
 910                        /* now goto beginning for ntlmssp authenticate phase */
 911                        if (rc)
 912                                goto ssetup_exit;
 913                }
 914                bcc_ptr += blob_len;
 915                bytes_remaining -= blob_len;
 916        }
 917
 918        /* BB check if Unicode and decode strings */
 919        if (bytes_remaining == 0) {
 920                /* no string area to decode, do nothing */
 921        } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
 922                /* unicode string area must be word-aligned */
 923                if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
 924                        ++bcc_ptr;
 925                        --bytes_remaining;
 926                }
 927                decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
 928        } else {
 929                rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining,
 930                                         ses, nls_cp);
 931        }
 932
 933ssetup_exit:
 934        if (spnego_key) {
 935                key_revoke(spnego_key);
 936                key_put(spnego_key);
 937        }
 938        kfree(str_area);
 939        kfree(ntlmsspblob);
 940        ntlmsspblob = NULL;
 941        if (resp_buf_type == CIFS_SMALL_BUFFER) {
 942                cFYI(1, "ssetup freeing small buf %p", iov[0].iov_base);
 943                cifs_small_buf_release(iov[0].iov_base);
 944        } else if (resp_buf_type == CIFS_LARGE_BUFFER)
 945                cifs_buf_release(iov[0].iov_base);
 946
 947        /* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */
 948        if ((phase == NtLmChallenge) && (rc == 0))
 949                goto ssetup_ntlmssp_authenticate;
 950
 951        return rc;
 952}
 953