auth/ntlmssp/ntlmssp_server.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    handle NTLMSSP, server side
   5
   6    Copyright (C) Andrew Tridgell      2001
   7    Copyright (C) Andrew Bartlett 2001-2010
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program 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 the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  21 */
  22
  23 #include "includes.h"
  24 #include "auth/ntlmssp/ntlmssp.h"
  25 #include "auth/ntlmssp/ntlmssp_private.h"
  26 #include "../librpc/gen_ndr/ndr_ntlmssp.h"
  27 #include "auth/ntlmssp/ntlmssp_ndr.h"
  28 #include "../libcli/auth/libcli_auth.h"
  29 #include "../lib/crypto/crypto.h"
  30 #include "auth/gensec/gensec.h"
  31 #include "auth/common_auth.h"
  32
  33 /**
  34  * Determine correct target name flags for reply, given server role
  35  * and negotiated flags
  36  *
  37  * @param ntlmssp_state NTLMSSP State
  38  * @param neg_flags The flags from the packet
  39  * @param chal_flags The flags to be set in the reply packet
  40  * @return The 'target name' string.
  41  */
  42
  43 const char *ntlmssp_target_name(struct ntlmssp_state *ntlmssp_state,
  44                                 uint32_t neg_flags, uint32_t *chal_flags)
  45 {
  46         if (neg_flags & NTLMSSP_REQUEST_TARGET) {
  47                 *chal_flags |= NTLMSSP_NEGOTIATE_TARGET_INFO;
  48                 *chal_flags |= NTLMSSP_REQUEST_TARGET;
  49                 if (ntlmssp_state->server.is_standalone) {
  50                         *chal_flags |= NTLMSSP_TARGET_TYPE_SERVER;
  51                         return ntlmssp_state->server.netbios_name;
  52                 } else {
  53                         *chal_flags |= NTLMSSP_TARGET_TYPE_DOMAIN;
  54                         return ntlmssp_state->server.netbios_domain;
  55                 };
  56         } else {
  57                 return "";
  58         }
  59 }
  60
  61 /**
  62  * Next state function for the NTLMSSP Negotiate packet
  63  *
  64  * @param gensec_security GENSEC state
  65  * @param out_mem_ctx Memory context for *out
  66  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
  67  * @param out The reply, as an allocated DATA_BLOB, caller to free.
  68  * @return Errors or MORE_PROCESSING_REQUIRED if (normal) a reply is required.
  69  */
  70
  71 NTSTATUS gensec_ntlmssp_server_negotiate(struct gensec_security *gensec_security,
  72                                          TALLOC_CTX *out_mem_ctx,
  73                                          const DATA_BLOB request, DATA_BLOB *reply)
  74 {
  75         struct gensec_ntlmssp_context *gensec_ntlmssp =
  76                 talloc_get_type_abort(gensec_security->private_data,
  77                                       struct gensec_ntlmssp_context);
  78         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
  79         struct auth4_context *auth_context = gensec_security->auth_context;
  80         DATA_BLOB struct_blob;
  81         uint32_t neg_flags = 0;
  82         uint32_t ntlmssp_command, chal_flags;
  83         uint8_t cryptkey[8];
  84         const char *target_name;
  85         NTSTATUS status;
  86
  87         /* parse the NTLMSSP packet */
  88 #if 0
  89         file_save("ntlmssp_negotiate.dat", request.data, request.length);
  90 #endif
  91
  92         if (request.length) {
  93                 if ((request.length < 16) || !msrpc_parse(ntlmssp_state, &request, "Cdd",
  94                                                           "NTLMSSP",
  95                                                           &ntlmssp_command,
  96                                                           &neg_flags)) {
  97                         DEBUG(1, ("ntlmssp_server_negotiate: failed to parse NTLMSSP Negotiate of length %u\n",
  98                                 (unsigned int)request.length));
  99                         dump_data(2, request.data, request.length);
 100                         return NT_STATUS_INVALID_PARAMETER;
 101                 }
 102                 debug_ntlmssp_flags(neg_flags);
 103
 104                 if (DEBUGLEVEL >= 10) {
 105                         struct NEGOTIATE_MESSAGE *negotiate = talloc(
 106                                 ntlmssp_state, struct NEGOTIATE_MESSAGE);
 107                         if (negotiate != NULL) {
 108                                 status = ntlmssp_pull_NEGOTIATE_MESSAGE(
 109                                         &request, negotiate, negotiate);
 110                                 if (NT_STATUS_IS_OK(status)) {
 111                                         NDR_PRINT_DEBUG(NEGOTIATE_MESSAGE,
 112                                                         negotiate);
 113                                 }
 114                                 TALLOC_FREE(negotiate);
 115                         }
 116                 }
 117         }
 118
 119         ntlmssp_handle_neg_flags(ntlmssp_state, neg_flags, ntlmssp_state->allow_lm_key);
 120
 121         /* Ask our caller what challenge they would like in the packet */
 122         if (auth_context->get_ntlm_challenge) {
 123                 status = auth_context->get_ntlm_challenge(auth_context, cryptkey);
 124                 if (!NT_STATUS_IS_OK(status)) {
 125                         DEBUG(1, ("gensec_ntlmssp_server_negotiate: failed to get challenge: %s\n",
 126                                   nt_errstr(status)));
 127                         return status;
 128                 }
 129         } else {
 130                 DEBUG(1, ("gensec_ntlmssp_server_negotiate: backend doesn't give a challenge\n"));
 131                 return NT_STATUS_NOT_IMPLEMENTED;
 132         }
 133
 134         /* The flags we send back are not just the negotiated flags,
 135          * they are also 'what is in this packet'.  Therfore, we
 136          * operate on 'chal_flags' from here on
 137          */
 138
 139         chal_flags = ntlmssp_state->neg_flags;
 140
 141         /* get the right name to fill in as 'target' */
 142         target_name = ntlmssp_target_name(ntlmssp_state,
 143                                           neg_flags, &chal_flags);
 144         if (target_name == NULL)
 145                 return NT_STATUS_INVALID_PARAMETER;
 146
 147         ntlmssp_state->chal = data_blob_talloc(ntlmssp_state, cryptkey, 8);
 148         ntlmssp_state->internal_chal = data_blob_talloc(ntlmssp_state,
 149                                                         cryptkey, 8);
 150
 151         /* This creates the 'blob' of names that appears at the end of the packet */
 152         if (chal_flags & NTLMSSP_NEGOTIATE_TARGET_INFO)
 153         {
 154                 status = msrpc_gen(ntlmssp_state, &struct_blob, "aaaaa",
 155                           MsvAvNbDomainName, target_name,
 156                           MsvAvNbComputerName, ntlmssp_state->server.netbios_name,
 157                           MsvAvDnsDomainName, ntlmssp_state->server.dns_domain,
 158                           MsvAvDnsComputerName, ntlmssp_state->server.dns_name,
 159                           MsvAvEOL, "");
 160                 if (!NT_STATUS_IS_OK(status)) {
 161                         return status;
 162                 }
 163         } else {
 164                 struct_blob = data_blob_null;
 165         }
 166
 167         {
 168                 /* Marshal the packet in the right format, be it unicode or ASCII */
 169                 const char *gen_string;
 170                 DATA_BLOB version_blob = data_blob_null;
 171
 172                 if (chal_flags & NTLMSSP_NEGOTIATE_VERSION) {
 173                         enum ndr_err_code err;
 174                         struct ntlmssp_VERSION vers;
 175
 176                         /* "What Windows returns" as a version number. */
 177                         ZERO_STRUCT(vers);
 178                         vers.ProductMajorVersion = NTLMSSP_WINDOWS_MAJOR_VERSION_6;
 179                         vers.ProductMinorVersion = NTLMSSP_WINDOWS_MINOR_VERSION_1;
 180                         vers.ProductBuild = 0;
 181                         vers.NTLMRevisionCurrent = NTLMSSP_REVISION_W2K3;
 182
 183                         err = ndr_push_struct_blob(&version_blob,
 184                                                 ntlmssp_state,
 185                                                 &vers,
 186                                                 (ndr_push_flags_fn_t)ndr_push_ntlmssp_VERSION);
 187
 188                         if (!NDR_ERR_CODE_IS_SUCCESS(err)) {
 189                                 data_blob_free(&struct_blob);
 190                                 return NT_STATUS_NO_MEMORY;
 191                         }
 192                 }
 193
 194                 if (ntlmssp_state->unicode) {
 195                         gen_string = "CdUdbddBb";
 196                 } else {
 197                         gen_string = "CdAdbddBb";
 198                 }
 199
 200                 status = msrpc_gen(out_mem_ctx, reply, gen_string,
 201                         "NTLMSSP",
 202                         NTLMSSP_CHALLENGE,
 203                         target_name,
 204                         chal_flags,
 205                         cryptkey, 8,
 206                         0, 0,
 207                         struct_blob.data, struct_blob.length,
 208                         version_blob.data, version_blob.length);
 209
 210                 if (!NT_STATUS_IS_OK(status)) {
 211                         data_blob_free(&version_blob);
 212                         data_blob_free(&struct_blob);
 213                         return status;
 214                 }
 215
 216                 data_blob_free(&version_blob);
 217
 218                 if (DEBUGLEVEL >= 10) {
 219                         struct CHALLENGE_MESSAGE *challenge = talloc(
 220                                 ntlmssp_state, struct CHALLENGE_MESSAGE);
 221                         if (challenge != NULL) {
 222                                 challenge->NegotiateFlags = chal_flags;
 223                                 status = ntlmssp_pull_CHALLENGE_MESSAGE(
 224                                         reply, challenge, challenge);
 225                                 if (NT_STATUS_IS_OK(status)) {
 226                                         NDR_PRINT_DEBUG(CHALLENGE_MESSAGE,
 227                                                         challenge);
 228                                 }
 229                                 TALLOC_FREE(challenge);
 230                         }
 231                 }
 232         }
 233
 234         data_blob_free(&struct_blob);
 235
 236         ntlmssp_state->expected_state = NTLMSSP_AUTH;
 237
 238         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 239 }
 240
 241 struct ntlmssp_server_auth_state {
 242         DATA_BLOB user_session_key;
 243         DATA_BLOB lm_session_key;
 244         /* internal variables used by KEY_EXCH (client-supplied user session key */
 245         DATA_BLOB encrypted_session_key;
 246         bool doing_ntlm2;
 247         /* internal variables used by NTLM2 */
 248         uint8_t session_nonce[16];
 249 };
 250
 251 /**
 252  * Next state function for the Authenticate packet
 253  *
 254  * @param ntlmssp_state NTLMSSP State
 255  * @param request The request, as a DATA_BLOB
 256  * @return Errors or NT_STATUS_OK.
 257  */
 258
 259 static NTSTATUS ntlmssp_server_preauth(struct gensec_security *gensec_security,
 260                                        struct gensec_ntlmssp_context *gensec_ntlmssp,
 261                                        struct ntlmssp_server_auth_state *state,
 262                                        const DATA_BLOB request)
 263 {
 264         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 265         struct auth4_context *auth_context = gensec_security->auth_context;
 266         uint32_t ntlmssp_command, auth_flags;
 267         NTSTATUS nt_status;
 268
 269         uint8_t session_nonce_hash[16];
 270
 271         const char *parse_string;
 272
 273 #if 0
 274         file_save("ntlmssp_auth.dat", request.data, request.length);
 275 #endif
 276
 277         if (ntlmssp_state->unicode) {
 278                 parse_string = "CdBBUUUBd";
 279         } else {
 280                 parse_string = "CdBBAAABd";
 281         }
 282
 283         /* zero these out */
 284         data_blob_free(&ntlmssp_state->session_key);
 285         data_blob_free(&ntlmssp_state->lm_resp);
 286         data_blob_free(&ntlmssp_state->nt_resp);
 287
 288         ntlmssp_state->user = NULL;
 289         ntlmssp_state->domain = NULL;
 290         ntlmssp_state->client.netbios_name = NULL;
 291
 292         /* now the NTLMSSP encoded auth hashes */
 293         if (!msrpc_parse(ntlmssp_state, &request, parse_string,
 294                          "NTLMSSP",
 295                          &ntlmssp_command,
 296                          &ntlmssp_state->lm_resp,
 297                          &ntlmssp_state->nt_resp,
 298                          &ntlmssp_state->domain,
 299                          &ntlmssp_state->user,
 300                          &ntlmssp_state->client.netbios_name,
 301                          &state->encrypted_session_key,
 302                          &auth_flags)) {
 303                 DEBUG(10, ("ntlmssp_server_auth: failed to parse NTLMSSP (nonfatal):\n"));
 304                 dump_data(10, request.data, request.length);
 305
 306                 /* zero this out */
 307                 data_blob_free(&state->encrypted_session_key);
 308                 auth_flags = 0;
 309
 310                 /* Try again with a shorter string (Win9X truncates this packet) */
 311                 if (ntlmssp_state->unicode) {
 312                         parse_string = "CdBBUUU";
 313                 } else {
 314                         parse_string = "CdBBAAA";
 315                 }
 316
 317                 /* now the NTLMSSP encoded auth hashes */
 318                 if (!msrpc_parse(ntlmssp_state, &request, parse_string,
 319                                  "NTLMSSP",
 320                                  &ntlmssp_command,
 321                                  &ntlmssp_state->lm_resp,
 322                                  &ntlmssp_state->nt_resp,
 323                                  &ntlmssp_state->domain,
 324                                  &ntlmssp_state->user,
 325                                  &ntlmssp_state->client.netbios_name)) {
 326                         DEBUG(1, ("ntlmssp_server_auth: failed to parse NTLMSSP (tried both formats):\n"));
 327                         dump_data(2, request.data, request.length);
 328
 329                         return NT_STATUS_INVALID_PARAMETER;
 330                 }
 331         }
 332
 333         talloc_steal(state, state->encrypted_session_key.data);
 334
 335         if (auth_flags)
 336                 ntlmssp_handle_neg_flags(ntlmssp_state, auth_flags, ntlmssp_state->allow_lm_key);
 337
 338         if (DEBUGLEVEL >= 10) {
 339                 struct AUTHENTICATE_MESSAGE *authenticate = talloc(
 340                         ntlmssp_state, struct AUTHENTICATE_MESSAGE);
 341                 if (authenticate != NULL) {
 342                         NTSTATUS status;
 343                         authenticate->NegotiateFlags = auth_flags;
 344                         status = ntlmssp_pull_AUTHENTICATE_MESSAGE(
 345                                 &request, authenticate, authenticate);
 346                         if (NT_STATUS_IS_OK(status)) {
 347                                 NDR_PRINT_DEBUG(AUTHENTICATE_MESSAGE,
 348                                                 authenticate);
 349                         }
 350                         TALLOC_FREE(authenticate);
 351                 }
 352         }
 353
 354         DEBUG(3,("Got user=[%s] domain=[%s] workstation=[%s] len1=%lu len2=%lu\n",
 355                  ntlmssp_state->user, ntlmssp_state->domain,
 356                  ntlmssp_state->client.netbios_name,
 357                  (unsigned long)ntlmssp_state->lm_resp.length,
 358                  (unsigned long)ntlmssp_state->nt_resp.length));
 359
 360 #if 0
 361         file_save("nthash1.dat",  &ntlmssp_state->nt_resp.data,  &ntlmssp_state->nt_resp.length);
 362         file_save("lmhash1.dat",  &ntlmssp_state->lm_resp.data,  &ntlmssp_state->lm_resp.length);
 363 #endif
 364
 365         /* NTLM2 uses a 'challenge' that is made of up both the server challenge, and a
 366            client challenge
 367
 368            However, the NTLM2 flag may still be set for the real NTLMv2 logins, be careful.
 369         */
 370         if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 371                 if (ntlmssp_state->nt_resp.length == 24 && ntlmssp_state->lm_resp.length == 24) {
 372                         struct MD5Context md5_session_nonce_ctx;
 373                         state->doing_ntlm2 = true;
 374
 375                         memcpy(state->session_nonce, ntlmssp_state->internal_chal.data, 8);
 376                         memcpy(&state->session_nonce[8], ntlmssp_state->lm_resp.data, 8);
 377
 378                         SMB_ASSERT(ntlmssp_state->internal_chal.data && ntlmssp_state->internal_chal.length == 8);
 379
 380                         MD5Init(&md5_session_nonce_ctx);
 381                         MD5Update(&md5_session_nonce_ctx, state->session_nonce, 16);
 382                         MD5Final(session_nonce_hash, &md5_session_nonce_ctx);
 383
 384                         /* LM response is no longer useful */
 385                         data_blob_free(&ntlmssp_state->lm_resp);
 386
 387                         /* We changed the effective challenge - set it */
 388                         if (auth_context->set_ntlm_challenge) {
 389                                 nt_status = auth_context->set_ntlm_challenge(auth_context,
 390                                                                              session_nonce_hash,
 391                                                                              "NTLMSSP callback (NTLM2)");
 392                                 if (!NT_STATUS_IS_OK(nt_status)) {
 393                                         DEBUG(1, ("gensec_ntlmssp_server_negotiate: failed to get challenge: %s\n",
 394                                                   nt_errstr(nt_status)));
 395                                         return nt_status;
 396                                 }
 397                         } else {
 398                                 DEBUG(1, ("gensec_ntlmssp_server_negotiate: backend doesn't have facility for challenge to be set\n"));
 399
 400                                 return NT_STATUS_NOT_IMPLEMENTED;
 401                         }
 402
 403                         /* LM Key is incompatible. */
 404                         ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 405                 }
 406         }
 407         return NT_STATUS_OK;
 408 }
 409
 410 /**
 411  * Check the password on an NTLMSSP login.
 412  *
 413  * Return the session keys used on the connection.
 414  */
 415
 416 static NTSTATUS ntlmssp_server_check_password(struct gensec_security *gensec_security,
 417                                               struct gensec_ntlmssp_context *gensec_ntlmssp,
 418                                               TALLOC_CTX *mem_ctx,
 419                                               DATA_BLOB *user_session_key, DATA_BLOB *lm_session_key)
 420 {
 421         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 422         struct auth4_context *auth_context = gensec_security->auth_context;
 423         NTSTATUS nt_status = NT_STATUS_NOT_IMPLEMENTED;
 424         struct auth_usersupplied_info *user_info;
 425
 426         user_info = talloc_zero(ntlmssp_state, struct auth_usersupplied_info);
 427         if (!user_info) {
 428                 return NT_STATUS_NO_MEMORY;
 429         }
 430
 431         user_info->logon_parameters = MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT | MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT;
 432         user_info->flags = 0;
 433         user_info->mapped_state = false;
 434         user_info->client.account_name = ntlmssp_state->user;
 435         user_info->client.domain_name = ntlmssp_state->domain;
 436         user_info->workstation_name = ntlmssp_state->client.netbios_name;
 437         user_info->remote_host = gensec_get_remote_address(gensec_security);
 438
 439         user_info->password_state = AUTH_PASSWORD_RESPONSE;
 440         user_info->password.response.lanman = ntlmssp_state->lm_resp;
 441         user_info->password.response.lanman.data = talloc_steal(user_info, ntlmssp_state->lm_resp.data);
 442         user_info->password.response.nt = ntlmssp_state->nt_resp;
 443         user_info->password.response.nt.data = talloc_steal(user_info, ntlmssp_state->nt_resp.data);
 444
 445         if (auth_context->check_ntlm_password) {
 446                 nt_status = auth_context->check_ntlm_password(auth_context,
 447                                                               gensec_ntlmssp,
 448                                                               user_info,
 449                                                               &gensec_ntlmssp->server_returned_info,
 450                                                               user_session_key, lm_session_key);
 451         }
 452         talloc_free(user_info);
 453
 454         if (!NT_STATUS_IS_OK(nt_status)) {
 455                 DEBUG(5, (__location__ ": Checking NTLMSSP password for %s\\%s failed: %s\n", user_info->client.domain_name, user_info->client.account_name, nt_errstr(nt_status)));
 456         }
 457
 458         NT_STATUS_NOT_OK_RETURN(nt_status);
 459
 460         talloc_steal(mem_ctx, user_session_key->data);
 461         talloc_steal(mem_ctx, lm_session_key->data);
 462
 463         return nt_status;
 464 }
 465
 466 /**
 467  * Next state function for the Authenticate packet
 468  * (after authentication - figures out the session keys etc)
 469  *
 470  * @param ntlmssp_state NTLMSSP State
 471  * @return Errors or NT_STATUS_OK.
 472  */
 473
 474 static NTSTATUS ntlmssp_server_postauth(struct gensec_security *gensec_security,
 475                                         struct gensec_ntlmssp_context *gensec_ntlmssp,
 476                                         struct ntlmssp_server_auth_state *state)
 477 {
 478         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 479         DATA_BLOB user_session_key = state->user_session_key;
 480         DATA_BLOB lm_session_key = state->lm_session_key;
 481         NTSTATUS nt_status = NT_STATUS_OK;
 482         DATA_BLOB session_key = data_blob(NULL, 0);
 483
 484         dump_data_pw("NT session key:\n", user_session_key.data, user_session_key.length);
 485         dump_data_pw("LM first-8:\n", lm_session_key.data, lm_session_key.length);
 486
 487         /* Handle the different session key derivation for NTLM2 */
 488         if (state->doing_ntlm2) {
 489                 if (user_session_key.data && user_session_key.length == 16) {
 490                         session_key = data_blob_talloc(ntlmssp_state,
 491                                                        NULL, 16);
 492                         hmac_md5(user_session_key.data, state->session_nonce,
 493                                  sizeof(state->session_nonce), session_key.data);
 494                         DEBUG(10,("ntlmssp_server_auth: Created NTLM2 session key.\n"));
 495                         dump_data_pw("NTLM2 session key:\n", session_key.data, session_key.length);
 496
 497                 } else {
 498                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM2 session key.\n"));
 499                         session_key = data_blob_null;
 500                 }
 501         } else if ((ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 502                 /* Ensure we can never get here on NTLMv2 */
 503                 && (ntlmssp_state->nt_resp.length == 0 || ntlmssp_state->nt_resp.length == 24)) {
 504
 505                 if (lm_session_key.data && lm_session_key.length >= 8) {
 506                         if (ntlmssp_state->lm_resp.data && ntlmssp_state->lm_resp.length == 24) {
 507                                 session_key = data_blob_talloc(ntlmssp_state,
 508                                                                NULL, 16);
 509                                 if (session_key.data == NULL) {
 510                                         return NT_STATUS_NO_MEMORY;
 511                                 }
 512                                 SMBsesskeygen_lm_sess_key(lm_session_key.data, ntlmssp_state->lm_resp.data,
 513                                                           session_key.data);
 514                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 515                         } else {
 516                                 static const uint8_t zeros[24] = {0, };
 517                                 session_key = data_blob_talloc(
 518                                         ntlmssp_state, NULL, 16);
 519                                 if (session_key.data == NULL) {
 520                                         return NT_STATUS_NO_MEMORY;
 521                                 }
 522                                 SMBsesskeygen_lm_sess_key(zeros, zeros,
 523                                                           session_key.data);
 524                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 525                         }
 526                         dump_data_pw("LM session key:\n", session_key.data,
 527                                      session_key.length);
 528                 } else {
 529                         /* LM Key not selected */
 530                         ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 531
 532                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM session key.\n"));
 533                         session_key = data_blob_null;
 534                 }
 535
 536         } else if (user_session_key.data) {
 537                 session_key = user_session_key;
 538                 DEBUG(10,("ntlmssp_server_auth: Using unmodified nt session key.\n"));
 539                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 540
 541                 /* LM Key not selected */
 542                 ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 543
 544         } else if (lm_session_key.data) {
 545                 /* Very weird to have LM key, but no user session key, but anyway.. */
 546                 session_key = lm_session_key;
 547                 DEBUG(10,("ntlmssp_server_auth: Using unmodified lm session key.\n"));
 548                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 549
 550                 /* LM Key not selected */
 551                 ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 552
 553         } else {
 554                 DEBUG(10,("ntlmssp_server_auth: Failed to create unmodified session key.\n"));
 555                 session_key = data_blob_null;
 556
 557                 /* LM Key not selected */
 558                 ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 559         }
 560
 561         /* With KEY_EXCH, the client supplies the proposed session key,
 562            but encrypts it with the long-term key */
 563         if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 564                 if (!state->encrypted_session_key.data
 565                     || state->encrypted_session_key.length != 16) {
 566                         DEBUG(1, ("Client-supplied KEY_EXCH session key was of invalid length (%u)!\n",
 567                                   (unsigned)state->encrypted_session_key.length));
 568                         return NT_STATUS_INVALID_PARAMETER;
 569                 } else if (!session_key.data || session_key.length != 16) {
 570                         DEBUG(5, ("server session key is invalid (len == %u), cannot do KEY_EXCH!\n",
 571                                   (unsigned int)session_key.length));
 572                         ntlmssp_state->session_key = session_key;
 573                         talloc_steal(ntlmssp_state, session_key.data);
 574                 } else {
 575                         dump_data_pw("KEY_EXCH session key (enc):\n",
 576                                      state->encrypted_session_key.data,
 577                                      state->encrypted_session_key.length);
 578                         arcfour_crypt(state->encrypted_session_key.data,
 579                                       session_key.data,
 580                                       state->encrypted_session_key.length);
 581                         ntlmssp_state->session_key = data_blob_talloc(ntlmssp_state,
 582                                                                       state->encrypted_session_key.data,
 583                                                                       state->encrypted_session_key.length);
 584                         dump_data_pw("KEY_EXCH session key:\n",
 585                                      state->encrypted_session_key.data,
 586                                      state->encrypted_session_key.length);
 587                 }
 588         } else {
 589                 ntlmssp_state->session_key = session_key;
 590                 talloc_steal(ntlmssp_state, session_key.data);
 591         }
 592
 593         if (ntlmssp_state->session_key.length) {
 594                 nt_status = ntlmssp_sign_init(ntlmssp_state);
 595         }
 596
 597         ntlmssp_state->expected_state = NTLMSSP_DONE;
 598
 599         return nt_status;
 600 }
 601
 602
 603 /**
 604  * Next state function for the NTLMSSP Authenticate packet
 605  *
 606  * @param gensec_security GENSEC state
 607  * @param out_mem_ctx Memory context for *out
 608  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
 609  * @param out The reply, as an allocated DATA_BLOB, caller to free.
 610  * @return Errors or NT_STATUS_OK if authentication sucessful
 611  */
 612
 613 NTSTATUS gensec_ntlmssp_server_auth(struct gensec_security *gensec_security,
 614                                     TALLOC_CTX *out_mem_ctx,
 615                                     const DATA_BLOB in, DATA_BLOB *out)
 616 {
 617         struct gensec_ntlmssp_context *gensec_ntlmssp =
 618                 talloc_get_type_abort(gensec_security->private_data,
 619                                       struct gensec_ntlmssp_context);
 620         struct ntlmssp_server_auth_state *state;
 621         NTSTATUS nt_status;
 622
 623         /* zero the outbound NTLMSSP packet */
 624         *out = data_blob_null;
 625
 626         state = talloc_zero(gensec_ntlmssp, struct ntlmssp_server_auth_state);
 627         if (state == NULL) {
 628                 return NT_STATUS_NO_MEMORY;
 629         }
 630
 631         nt_status = ntlmssp_server_preauth(gensec_security, gensec_ntlmssp, state, in);
 632         if (!NT_STATUS_IS_OK(nt_status)) {
 633                 TALLOC_FREE(state);
 634                 return nt_status;
 635         }
 636
 637         /*
 638          * Note we don't check here for NTLMv2 auth settings. If NTLMv2 auth
 639          * is required (by "ntlm auth = no" and "lm auth = no" being set in the
 640          * smb.conf file) and no NTLMv2 response was sent then the password check
 641          * will fail here. JRA.
 642          */
 643
 644         /* Finally, actually ask if the password is OK */
 645         nt_status = ntlmssp_server_check_password(gensec_security, gensec_ntlmssp,
 646                                                   state,
 647                                                   &state->user_session_key,
 648                                                   &state->lm_session_key);
 649         if (!NT_STATUS_IS_OK(nt_status)) {
 650                 TALLOC_FREE(state);
 651                 return nt_status;
 652         }
 653
 654         /* When we get more async in the auth code behind
 655            ntlmssp_state->check_password, the ntlmssp_server_postpath
 656            can be done in a callback */
 657
 658         nt_status = ntlmssp_server_postauth(gensec_security, gensec_ntlmssp, state);
 659         TALLOC_FREE(state);
 660         return nt_status;
 661 }