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 cifs_ses *ses)
  41{
  42        struct list_head *tmp;
  43        struct cifs_ses *tmp_ses;
  44
  45        list_for_each(tmp, &ses->server->smb_ses_list) {
  46                tmp_ses = list_entry(tmp, struct cifs_ses,
  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 cifs_ses *ses)
  65{
  66        __u16 vcnum = 0;
  67        struct list_head *tmp;
  68        struct cifs_ses *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 cifs_ses,
  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 cifs_ses *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(min_t(u32,
 128                                        CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
 129                                        USHRT_MAX));
 130        pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);
 131        pSMB->req.VcNumber = get_next_vcnum(ses);
 132
 133        /* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
 134
 135        /* BB verify whether signing required on neg or just on auth frame
 136           (and NTLM case) */
 137
 138        capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
 139                        CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
 140
 141        if (ses->server->sec_mode &
 142            (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
 143                pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
 144
 145        if (ses->capabilities & CAP_UNICODE) {
 146                pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
 147                capabilities |= CAP_UNICODE;
 148        }
 149        if (ses->capabilities & CAP_STATUS32) {
 150                pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
 151                capabilities |= CAP_STATUS32;
 152        }
 153        if (ses->capabilities & CAP_DFS) {
 154                pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
 155                capabilities |= CAP_DFS;
 156        }
 157        if (ses->capabilities & CAP_UNIX)
 158                capabilities |= CAP_UNIX;
 159
 160        return capabilities;
 161}
 162
 163static void
 164unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
 165{
 166        char *bcc_ptr = *pbcc_area;
 167        int bytes_ret = 0;
 168
 169        /* Copy OS version */
 170        bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
 171                                    nls_cp);
 172        bcc_ptr += 2 * bytes_ret;
 173        bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
 174                                    32, nls_cp);
 175        bcc_ptr += 2 * bytes_ret;
 176        bcc_ptr += 2; /* trailing null */
 177
 178        bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
 179                                    32, nls_cp);
 180        bcc_ptr += 2 * bytes_ret;
 181        bcc_ptr += 2; /* trailing null */
 182
 183        *pbcc_area = bcc_ptr;
 184}
 185
 186static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
 187                                   const struct nls_table *nls_cp)
 188{
 189        char *bcc_ptr = *pbcc_area;
 190        int bytes_ret = 0;
 191
 192        /* copy domain */
 193        if (ses->domainName == NULL) {
 194                /* Sending null domain better than using a bogus domain name (as
 195                we did briefly in 2.6.18) since server will use its default */
 196                *bcc_ptr = 0;
 197                *(bcc_ptr+1) = 0;
 198                bytes_ret = 0;
 199        } else
 200                bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
 201                                            256, nls_cp);
 202        bcc_ptr += 2 * bytes_ret;
 203        bcc_ptr += 2;  /* account for null terminator */
 204
 205        *pbcc_area = bcc_ptr;
 206}
 207
 208
 209static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
 210                                   const struct nls_table *nls_cp)
 211{
 212        char *bcc_ptr = *pbcc_area;
 213        int bytes_ret = 0;
 214
 215        /* BB FIXME add check that strings total less
 216        than 335 or will need to send them as arrays */
 217
 218        /* unicode strings, must be word aligned before the call */
 219/*      if ((long) bcc_ptr % 2) {
 220                *bcc_ptr = 0;
 221                bcc_ptr++;
 222        } */
 223        /* copy user */
 224        if (ses->user_name == NULL) {
 225                /* null user mount */
 226                *bcc_ptr = 0;
 227                *(bcc_ptr+1) = 0;
 228        } else {
 229                bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
 230                                            MAX_USERNAME_SIZE, nls_cp);
 231        }
 232        bcc_ptr += 2 * bytes_ret;
 233        bcc_ptr += 2; /* account for null termination */
 234
 235        unicode_domain_string(&bcc_ptr, ses, nls_cp);
 236        unicode_oslm_strings(&bcc_ptr, nls_cp);
 237
 238        *pbcc_area = bcc_ptr;
 239}
 240
 241static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
 242                                 const struct nls_table *nls_cp)
 243{
 244        char *bcc_ptr = *pbcc_area;
 245
 246        /* copy user */
 247        /* BB what about null user mounts - check that we do this BB */
 248        /* copy user */
 249        if (ses->user_name != NULL) {
 250                strncpy(bcc_ptr, ses->user_name, MAX_USERNAME_SIZE);
 251                bcc_ptr += strnlen(ses->user_name, MAX_USERNAME_SIZE);
 252        }
 253        /* else null user mount */
 254        *bcc_ptr = 0;
 255        bcc_ptr++; /* account for null termination */
 256
 257        /* copy domain */
 258        if (ses->domainName != NULL) {
 259                strncpy(bcc_ptr, ses->domainName, 256);
 260                bcc_ptr += strnlen(ses->domainName, 256);
 261        } /* else we will send a null domain name
 262             so the server will default to its own domain */
 263        *bcc_ptr = 0;
 264        bcc_ptr++;
 265
 266        /* BB check for overflow here */
 267
 268        strcpy(bcc_ptr, "Linux version ");
 269        bcc_ptr += strlen("Linux version ");
 270        strcpy(bcc_ptr, init_utsname()->release);
 271        bcc_ptr += strlen(init_utsname()->release) + 1;
 272
 273        strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
 274        bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
 275
 276        *pbcc_area = bcc_ptr;
 277}
 278
 279static void
 280decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
 281                      const struct nls_table *nls_cp)
 282{
 283        int len;
 284        char *data = *pbcc_area;
 285
 286        cFYI(1, "bleft %d", bleft);
 287
 288        kfree(ses->serverOS);
 289        ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
 290        cFYI(1, "serverOS=%s", ses->serverOS);
 291        len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
 292        data += len;
 293        bleft -= len;
 294        if (bleft <= 0)
 295                return;
 296
 297        kfree(ses->serverNOS);
 298        ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
 299        cFYI(1, "serverNOS=%s", ses->serverNOS);
 300        len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
 301        data += len;
 302        bleft -= len;
 303        if (bleft <= 0)
 304                return;
 305
 306        kfree(ses->serverDomain);
 307        ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
 308        cFYI(1, "serverDomain=%s", ses->serverDomain);
 309
 310        return;
 311}
 312
 313static int decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
 314                               struct cifs_ses *ses,
 315                               const struct nls_table *nls_cp)
 316{
 317        int rc = 0;
 318        int len;
 319        char *bcc_ptr = *pbcc_area;
 320
 321        cFYI(1, "decode sessetup ascii. bleft %d", bleft);
 322
 323        len = strnlen(bcc_ptr, bleft);
 324        if (len >= bleft)
 325                return rc;
 326
 327        kfree(ses->serverOS);
 328
 329        ses->serverOS = kzalloc(len + 1, GFP_KERNEL);
 330        if (ses->serverOS)
 331                strncpy(ses->serverOS, bcc_ptr, len);
 332        if (strncmp(ses->serverOS, "OS/2", 4) == 0) {
 333                        cFYI(1, "OS/2 server");
 334                        ses->flags |= CIFS_SES_OS2;
 335        }
 336
 337        bcc_ptr += len + 1;
 338        bleft -= len + 1;
 339
 340        len = strnlen(bcc_ptr, bleft);
 341        if (len >= bleft)
 342                return rc;
 343
 344        kfree(ses->serverNOS);
 345
 346        ses->serverNOS = kzalloc(len + 1, GFP_KERNEL);
 347        if (ses->serverNOS)
 348                strncpy(ses->serverNOS, bcc_ptr, len);
 349
 350        bcc_ptr += len + 1;
 351        bleft -= len + 1;
 352
 353        len = strnlen(bcc_ptr, bleft);
 354        if (len > bleft)
 355                return rc;
 356
 357        /* No domain field in LANMAN case. Domain is
 358           returned by old servers in the SMB negprot response */
 359        /* BB For newer servers which do not support Unicode,
 360           but thus do return domain here we could add parsing
 361           for it later, but it is not very important */
 362        cFYI(1, "ascii: bytes left %d", bleft);
 363
 364        return rc;
 365}
 366
 367int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
 368                                    struct cifs_ses *ses)
 369{
 370        unsigned int tioffset; /* challenge message target info area */
 371        unsigned int tilen; /* challenge message target info area length  */
 372
 373        CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
 374
 375        if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
 376                cERROR(1, "challenge blob len %d too small", blob_len);
 377                return -EINVAL;
 378        }
 379
 380        if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
 381                cERROR(1, "blob signature incorrect %s", pblob->Signature);
 382                return -EINVAL;
 383        }
 384        if (pblob->MessageType != NtLmChallenge) {
 385                cERROR(1, "Incorrect message type %d", pblob->MessageType);
 386                return -EINVAL;
 387        }
 388
 389        memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
 390        /* BB we could decode pblob->NegotiateFlags; some may be useful */
 391        /* In particular we can examine sign flags */
 392        /* BB spec says that if AvId field of MsvAvTimestamp is populated then
 393                we must set the MIC field of the AUTHENTICATE_MESSAGE */
 394        ses->ntlmssp->server_flags = le32_to_cpu(pblob->NegotiateFlags);
 395        tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
 396        tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
 397        if (tioffset > blob_len || tioffset + tilen > blob_len) {
 398                cERROR(1, "tioffset + tilen too high %u + %u", tioffset, tilen);
 399                return -EINVAL;
 400        }
 401        if (tilen) {
 402                ses->auth_key.response = kmalloc(tilen, GFP_KERNEL);
 403                if (!ses->auth_key.response) {
 404                        cERROR(1, "Challenge target info allocation failure");
 405                        return -ENOMEM;
 406                }
 407                memcpy(ses->auth_key.response, bcc_ptr + tioffset, tilen);
 408                ses->auth_key.len = tilen;
 409        }
 410
 411        return 0;
 412}
 413
 414/* BB Move to ntlmssp.c eventually */
 415
 416/* We do not malloc the blob, it is passed in pbuffer, because
 417   it is fixed size, and small, making this approach cleaner */
 418void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
 419                                         struct cifs_ses *ses)
 420{
 421        NEGOTIATE_MESSAGE *sec_blob = (NEGOTIATE_MESSAGE *)pbuffer;
 422        __u32 flags;
 423
 424        memset(pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
 425        memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
 426        sec_blob->MessageType = NtLmNegotiate;
 427
 428        /* BB is NTLMV2 session security format easier to use here? */
 429        flags = NTLMSSP_NEGOTIATE_56 |  NTLMSSP_REQUEST_TARGET |
 430                NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
 431                NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
 432        if (ses->server->sec_mode &
 433                        (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
 434                flags |= NTLMSSP_NEGOTIATE_SIGN;
 435                if (!ses->server->session_estab)
 436                        flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
 437        }
 438
 439        sec_blob->NegotiateFlags = cpu_to_le32(flags);
 440
 441        sec_blob->WorkstationName.BufferOffset = 0;
 442        sec_blob->WorkstationName.Length = 0;
 443        sec_blob->WorkstationName.MaximumLength = 0;
 444
 445        /* Domain name is sent on the Challenge not Negotiate NTLMSSP request */
 446        sec_blob->DomainName.BufferOffset = 0;
 447        sec_blob->DomainName.Length = 0;
 448        sec_blob->DomainName.MaximumLength = 0;
 449}
 450
 451/* We do not malloc the blob, it is passed in pbuffer, because its
 452   maximum possible size is fixed and small, making this approach cleaner.
 453   This function returns the length of the data in the blob */
 454int build_ntlmssp_auth_blob(unsigned char *pbuffer,
 455                                        u16 *buflen,
 456                                   struct cifs_ses *ses,
 457                                   const struct nls_table *nls_cp)
 458{
 459        int rc;
 460        AUTHENTICATE_MESSAGE *sec_blob = (AUTHENTICATE_MESSAGE *)pbuffer;
 461        __u32 flags;
 462        unsigned char *tmp;
 463
 464        memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
 465        sec_blob->MessageType = NtLmAuthenticate;
 466
 467        flags = NTLMSSP_NEGOTIATE_56 |
 468                NTLMSSP_REQUEST_TARGET | NTLMSSP_NEGOTIATE_TARGET_INFO |
 469                NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
 470                NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC;
 471        if (ses->server->sec_mode &
 472           (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
 473                flags |= NTLMSSP_NEGOTIATE_SIGN;
 474                if (!ses->server->session_estab)
 475                        flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
 476        }
 477
 478        tmp = pbuffer + sizeof(AUTHENTICATE_MESSAGE);
 479        sec_blob->NegotiateFlags = cpu_to_le32(flags);
 480
 481        sec_blob->LmChallengeResponse.BufferOffset =
 482                                cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
 483        sec_blob->LmChallengeResponse.Length = 0;
 484        sec_blob->LmChallengeResponse.MaximumLength = 0;
 485
 486        sec_blob->NtChallengeResponse.BufferOffset = cpu_to_le32(tmp - pbuffer);
 487        rc = setup_ntlmv2_rsp(ses, nls_cp);
 488        if (rc) {
 489                cERROR(1, "Error %d during NTLMSSP authentication", rc);
 490                goto setup_ntlmv2_ret;
 491        }
 492        memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
 493                        ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 494        tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
 495
 496        sec_blob->NtChallengeResponse.Length =
 497                        cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 498        sec_blob->NtChallengeResponse.MaximumLength =
 499                        cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 500
 501        if (ses->domainName == NULL) {
 502                sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 503                sec_blob->DomainName.Length = 0;
 504                sec_blob->DomainName.MaximumLength = 0;
 505                tmp += 2;
 506        } else {
 507                int len;
 508                len = cifs_strtoUTF16((__le16 *)tmp, ses->domainName,
 509                                      MAX_USERNAME_SIZE, nls_cp);
 510                len *= 2; /* unicode is 2 bytes each */
 511                sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 512                sec_blob->DomainName.Length = cpu_to_le16(len);
 513                sec_blob->DomainName.MaximumLength = cpu_to_le16(len);
 514                tmp += len;
 515        }
 516
 517        if (ses->user_name == NULL) {
 518                sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 519                sec_blob->UserName.Length = 0;
 520                sec_blob->UserName.MaximumLength = 0;
 521                tmp += 2;
 522        } else {
 523                int len;
 524                len = cifs_strtoUTF16((__le16 *)tmp, ses->user_name,
 525                                      MAX_USERNAME_SIZE, nls_cp);
 526                len *= 2; /* unicode is 2 bytes each */
 527                sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 528                sec_blob->UserName.Length = cpu_to_le16(len);
 529                sec_blob->UserName.MaximumLength = cpu_to_le16(len);
 530                tmp += len;
 531        }
 532
 533        sec_blob->WorkstationName.BufferOffset = cpu_to_le32(tmp - pbuffer);
 534        sec_blob->WorkstationName.Length = 0;
 535        sec_blob->WorkstationName.MaximumLength = 0;
 536        tmp += 2;
 537
 538        if (((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) ||
 539                (ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC))
 540                        && !calc_seckey(ses)) {
 541                memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
 542                sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
 543                sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
 544                sec_blob->SessionKey.MaximumLength =
 545                                cpu_to_le16(CIFS_CPHTXT_SIZE);
 546                tmp += CIFS_CPHTXT_SIZE;
 547        } else {
 548                sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - pbuffer);
 549                sec_blob->SessionKey.Length = 0;
 550                sec_blob->SessionKey.MaximumLength = 0;
 551        }
 552
 553setup_ntlmv2_ret:
 554        *buflen = tmp - pbuffer;
 555        return rc;
 556}
 557
 558int
 559CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 560               const struct nls_table *nls_cp)
 561{
 562        int rc = 0;
 563        int wct;
 564        struct smb_hdr *smb_buf;
 565        char *bcc_ptr;
 566        char *str_area;
 567        SESSION_SETUP_ANDX *pSMB;
 568        __u32 capabilities;
 569        __u16 count;
 570        int resp_buf_type;
 571        struct kvec iov[3];
 572        enum securityEnum type;
 573        __u16 action, bytes_remaining;
 574        struct key *spnego_key = NULL;
 575        __le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
 576        u16 blob_len;
 577        char *ntlmsspblob = NULL;
 578
 579        if (ses == NULL)
 580                return -EINVAL;
 581
 582        type = ses->server->secType;
 583        cFYI(1, "sess setup type %d", type);
 584        if (type == RawNTLMSSP) {
 585                /* if memory allocation is successful, caller of this function
 586                 * frees it.
 587                 */
 588                ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
 589                if (!ses->ntlmssp)
 590                        return -ENOMEM;
 591        }
 592
 593ssetup_ntlmssp_authenticate:
 594        if (phase == NtLmChallenge)
 595                phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
 596
 597        if (type == LANMAN) {
 598#ifndef CONFIG_CIFS_WEAK_PW_HASH
 599                /* LANMAN and plaintext are less secure and off by default.
 600                So we make this explicitly be turned on in kconfig (in the
 601                build) and turned on at runtime (changed from the default)
 602                in proc/fs/cifs or via mount parm.  Unfortunately this is
 603                needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
 604                return -EOPNOTSUPP;
 605#endif
 606                wct = 10; /* lanman 2 style sessionsetup */
 607        } else if ((type == NTLM) || (type == NTLMv2)) {
 608                /* For NTLMv2 failures eventually may need to retry NTLM */
 609                wct = 13; /* old style NTLM sessionsetup */
 610        } else /* same size: negotiate or auth, NTLMSSP or extended security */
 611                wct = 12;
 612
 613        rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
 614                            (void **)&smb_buf);
 615        if (rc)
 616                return rc;
 617
 618        pSMB = (SESSION_SETUP_ANDX *)smb_buf;
 619
 620        capabilities = cifs_ssetup_hdr(ses, pSMB);
 621
 622        /* we will send the SMB in three pieces:
 623        a fixed length beginning part, an optional
 624        SPNEGO blob (which can be zero length), and a
 625        last part which will include the strings
 626        and rest of bcc area. This allows us to avoid
 627        a large buffer 17K allocation */
 628        iov[0].iov_base = (char *)pSMB;
 629        iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
 630
 631        /* setting this here allows the code at the end of the function
 632           to free the request buffer if there's an error */
 633        resp_buf_type = CIFS_SMALL_BUFFER;
 634
 635        /* 2000 big enough to fit max user, domain, NOS name etc. */
 636        str_area = kmalloc(2000, GFP_KERNEL);
 637        if (str_area == NULL) {
 638                rc = -ENOMEM;
 639                goto ssetup_exit;
 640        }
 641        bcc_ptr = str_area;
 642
 643        ses->flags &= ~CIFS_SES_LANMAN;
 644
 645        iov[1].iov_base = NULL;
 646        iov[1].iov_len = 0;
 647
 648        if (type == LANMAN) {
 649#ifdef CONFIG_CIFS_WEAK_PW_HASH
 650                char lnm_session_key[CIFS_AUTH_RESP_SIZE];
 651
 652                pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
 653
 654                /* no capabilities flags in old lanman negotiation */
 655
 656                pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
 657
 658                /* Calculate hash with password and copy into bcc_ptr.
 659                 * Encryption Key (stored as in cryptkey) gets used if the
 660                 * security mode bit in Negottiate Protocol response states
 661                 * to use challenge/response method (i.e. Password bit is 1).
 662                 */
 663
 664                rc = calc_lanman_hash(ses->password, ses->server->cryptkey,
 665                                 ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
 666                                        true : false, lnm_session_key);
 667
 668                ses->flags |= CIFS_SES_LANMAN;
 669                memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
 670                bcc_ptr += CIFS_AUTH_RESP_SIZE;
 671
 672                /* can not sign if LANMAN negotiated so no need
 673                to calculate signing key? but what if server
 674                changed to do higher than lanman dialect and
 675                we reconnected would we ever calc signing_key? */
 676
 677                cFYI(1, "Negotiating LANMAN setting up strings");
 678                /* Unicode not allowed for LANMAN dialects */
 679                ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
 680#endif
 681        } else if (type == NTLM) {
 682                pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
 683                pSMB->req_no_secext.CaseInsensitivePasswordLength =
 684                        cpu_to_le16(CIFS_AUTH_RESP_SIZE);
 685                pSMB->req_no_secext.CaseSensitivePasswordLength =
 686                        cpu_to_le16(CIFS_AUTH_RESP_SIZE);
 687
 688                /* calculate ntlm response and session key */
 689                rc = setup_ntlm_response(ses, nls_cp);
 690                if (rc) {
 691                        cERROR(1, "Error %d during NTLM authentication", rc);
 692                        goto ssetup_exit;
 693                }
 694
 695                /* copy ntlm response */
 696                memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
 697                                CIFS_AUTH_RESP_SIZE);
 698                bcc_ptr += CIFS_AUTH_RESP_SIZE;
 699                memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
 700                                CIFS_AUTH_RESP_SIZE);
 701                bcc_ptr += CIFS_AUTH_RESP_SIZE;
 702
 703                if (ses->capabilities & CAP_UNICODE) {
 704                        /* unicode strings must be word aligned */
 705                        if (iov[0].iov_len % 2) {
 706                                *bcc_ptr = 0;
 707                                bcc_ptr++;
 708                        }
 709                        unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
 710                } else
 711                        ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
 712        } else if (type == NTLMv2) {
 713                pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
 714
 715                /* LM2 password would be here if we supported it */
 716                pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
 717
 718                /* calculate nlmv2 response and session key */
 719                rc = setup_ntlmv2_rsp(ses, nls_cp);
 720                if (rc) {
 721                        cERROR(1, "Error %d during NTLMv2 authentication", rc);
 722                        goto ssetup_exit;
 723                }
 724                memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
 725                                ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 726                bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
 727
 728                /* set case sensitive password length after tilen may get
 729                 * assigned, tilen is 0 otherwise.
 730                 */
 731                pSMB->req_no_secext.CaseSensitivePasswordLength =
 732                        cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
 733
 734                if (ses->capabilities & CAP_UNICODE) {
 735                        if (iov[0].iov_len % 2) {
 736                                *bcc_ptr = 0;
 737                                bcc_ptr++;
 738                        }
 739                        unicode_ssetup_strings(&bcc_ptr, ses, nls_cp);
 740                } else
 741                        ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
 742        } else if (type == Kerberos) {
 743#ifdef CONFIG_CIFS_UPCALL
 744                struct cifs_spnego_msg *msg;
 745
 746                spnego_key = cifs_get_spnego_key(ses);
 747                if (IS_ERR(spnego_key)) {
 748                        rc = PTR_ERR(spnego_key);
 749                        spnego_key = NULL;
 750                        goto ssetup_exit;
 751                }
 752
 753                msg = spnego_key->payload.data;
 754                /* check version field to make sure that cifs.upcall is
 755                   sending us a response in an expected form */
 756                if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
 757                        cERROR(1, "incorrect version of cifs.upcall (expected"
 758                                   " %d but got %d)",
 759                                   CIFS_SPNEGO_UPCALL_VERSION, msg->version);
 760                        rc = -EKEYREJECTED;
 761                        goto ssetup_exit;
 762                }
 763
 764                ses->auth_key.response = kmalloc(msg->sesskey_len, GFP_KERNEL);
 765                if (!ses->auth_key.response) {
 766                        cERROR(1, "Kerberos can't allocate (%u bytes) memory",
 767                                        msg->sesskey_len);
 768                        rc = -ENOMEM;
 769                        goto ssetup_exit;
 770                }
 771                memcpy(ses->auth_key.response, msg->data, msg->sesskey_len);
 772                ses->auth_key.len = msg->sesskey_len;
 773
 774                pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
 775                capabilities |= CAP_EXTENDED_SECURITY;
 776                pSMB->req.Capabilities = cpu_to_le32(capabilities);
 777                iov[1].iov_base = msg->data + msg->sesskey_len;
 778                iov[1].iov_len = msg->secblob_len;
 779                pSMB->req.SecurityBlobLength = cpu_to_le16(iov[1].iov_len);
 780
 781                if (ses->capabilities & CAP_UNICODE) {
 782                        /* unicode strings must be word aligned */
 783                        if ((iov[0].iov_len + iov[1].iov_len) % 2) {
 784                                *bcc_ptr = 0;
 785                                bcc_ptr++;
 786                        }
 787                        unicode_oslm_strings(&bcc_ptr, nls_cp);
 788                        unicode_domain_string(&bcc_ptr, ses, nls_cp);
 789                } else
 790                /* BB: is this right? */
 791                        ascii_ssetup_strings(&bcc_ptr, ses, nls_cp);
 792#else /* ! CONFIG_CIFS_UPCALL */
 793                cERROR(1, "Kerberos negotiated but upcall support disabled!");
 794                rc = -ENOSYS;
 795                goto ssetup_exit;
 796#endif /* CONFIG_CIFS_UPCALL */
 797        } else if (type == RawNTLMSSP) {
 798                if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
 799                        cERROR(1, "NTLMSSP requires Unicode support");
 800                        rc = -ENOSYS;
 801                        goto ssetup_exit;
 802                }
 803
 804                cFYI(1, "ntlmssp session setup phase %d", phase);
 805                pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
 806                capabilities |= CAP_EXTENDED_SECURITY;
 807                pSMB->req.Capabilities |= cpu_to_le32(capabilities);
 808                switch(phase) {
 809                case NtLmNegotiate:
 810                        build_ntlmssp_negotiate_blob(
 811                                pSMB->req.SecurityBlob, ses);
 812                        iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
 813                        iov[1].iov_base = pSMB->req.SecurityBlob;
 814                        pSMB->req.SecurityBlobLength =
 815                                cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
 816                        break;
 817                case NtLmAuthenticate:
 818                        /*
 819                         * 5 is an empirical value, large enough to hold
 820                         * authenticate message plus max 10 of av paris,
 821                         * domain, user, workstation names, flags, etc.
 822                         */
 823                        ntlmsspblob = kzalloc(
 824                                5*sizeof(struct _AUTHENTICATE_MESSAGE),
 825                                GFP_KERNEL);
 826                        if (!ntlmsspblob) {
 827                                cERROR(1, "Can't allocate NTLMSSP blob");
 828                                rc = -ENOMEM;
 829                                goto ssetup_exit;
 830                        }
 831
 832                        rc = build_ntlmssp_auth_blob(ntlmsspblob,
 833                                                &blob_len, ses, nls_cp);
 834                        if (rc)
 835                                goto ssetup_exit;
 836                        iov[1].iov_len = blob_len;
 837                        iov[1].iov_base = ntlmsspblob;
 838                        pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
 839                        /*
 840                         * Make sure that we tell the server that we are using
 841                         * the uid that it just gave us back on the response
 842                         * (challenge)
 843                         */
 844                        smb_buf->Uid = ses->Suid;
 845                        break;
 846                default:
 847                        cERROR(1, "invalid phase %d", phase);
 848                        rc = -ENOSYS;
 849                        goto ssetup_exit;
 850                }
 851                /* unicode strings must be word aligned */
 852                if ((iov[0].iov_len + iov[1].iov_len) % 2) {
 853                        *bcc_ptr = 0;
 854                        bcc_ptr++;
 855                }
 856                unicode_oslm_strings(&bcc_ptr, nls_cp);
 857        } else {
 858                cERROR(1, "secType %d not supported!", type);
 859                rc = -ENOSYS;
 860                goto ssetup_exit;
 861        }
 862
 863        iov[2].iov_base = str_area;
 864        iov[2].iov_len = (long) bcc_ptr - (long) str_area;
 865
 866        count = iov[1].iov_len + iov[2].iov_len;
 867        smb_buf->smb_buf_length =
 868                cpu_to_be32(be32_to_cpu(smb_buf->smb_buf_length) + count);
 869
 870        put_bcc(count, smb_buf);
 871
 872        rc = SendReceive2(xid, ses, iov, 3 /* num_iovecs */, &resp_buf_type,
 873                          CIFS_LOG_ERROR);
 874        /* SMB request buf freed in SendReceive2 */
 875
 876        pSMB = (SESSION_SETUP_ANDX *)iov[0].iov_base;
 877        smb_buf = (struct smb_hdr *)iov[0].iov_base;
 878
 879        if ((type == RawNTLMSSP) && (resp_buf_type != CIFS_NO_BUFFER) &&
 880            (smb_buf->Status.CifsError ==
 881                        cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))) {
 882                if (phase != NtLmNegotiate) {
 883                        cERROR(1, "Unexpected more processing error");
 884                        goto ssetup_exit;
 885                }
 886                /* NTLMSSP Negotiate sent now processing challenge (response) */
 887                phase = NtLmChallenge; /* process ntlmssp challenge */
 888                rc = 0; /* MORE_PROC rc is not an error here, but expected */
 889        }
 890        if (rc)
 891                goto ssetup_exit;
 892
 893        if ((smb_buf->WordCount != 3) && (smb_buf->WordCount != 4)) {
 894                rc = -EIO;
 895                cERROR(1, "bad word count %d", smb_buf->WordCount);
 896                goto ssetup_exit;
 897        }
 898        action = le16_to_cpu(pSMB->resp.Action);
 899        if (action & GUEST_LOGIN)
 900                cFYI(1, "Guest login"); /* BB mark SesInfo struct? */
 901        ses->Suid = smb_buf->Uid;   /* UID left in wire format (le) */
 902        cFYI(1, "UID = %llu ", ses->Suid);
 903        /* response can have either 3 or 4 word count - Samba sends 3 */
 904        /* and lanman response is 3 */
 905        bytes_remaining = get_bcc(smb_buf);
 906        bcc_ptr = pByteArea(smb_buf);
 907
 908        if (smb_buf->WordCount == 4) {
 909                blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
 910                if (blob_len > bytes_remaining) {
 911                        cERROR(1, "bad security blob length %d", blob_len);
 912                        rc = -EINVAL;
 913                        goto ssetup_exit;
 914                }
 915                if (phase == NtLmChallenge) {
 916                        rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
 917                        /* now goto beginning for ntlmssp authenticate phase */
 918                        if (rc)
 919                                goto ssetup_exit;
 920                }
 921                bcc_ptr += blob_len;
 922                bytes_remaining -= blob_len;
 923        }
 924
 925        /* BB check if Unicode and decode strings */
 926        if (bytes_remaining == 0) {
 927                /* no string area to decode, do nothing */
 928        } else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
 929                /* unicode string area must be word-aligned */
 930                if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
 931                        ++bcc_ptr;
 932                        --bytes_remaining;
 933                }
 934                decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses, nls_cp);
 935        } else {
 936                rc = decode_ascii_ssetup(&bcc_ptr, bytes_remaining,
 937                                         ses, nls_cp);
 938        }
 939
 940ssetup_exit:
 941        if (spnego_key) {
 942                key_invalidate(spnego_key);
 943                key_put(spnego_key);
 944        }
 945        kfree(str_area);
 946        kfree(ntlmsspblob);
 947        ntlmsspblob = NULL;
 948        if (resp_buf_type == CIFS_SMALL_BUFFER) {
 949                cFYI(1, "ssetup freeing small buf %p", iov[0].iov_base);
 950                cifs_small_buf_release(iov[0].iov_base);
 951        } else if (resp_buf_type == CIFS_LARGE_BUFFER)
 952                cifs_buf_release(iov[0].iov_base);
 953
 954        /* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */
 955        if ((phase == NtLmChallenge) && (rc == 0))
 956                goto ssetup_ntlmssp_authenticate;
 957
 958        return rc;
 959}
 960
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