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/gensec/gensec_internal.h"
  32 #include "auth/common_auth.h"
  33
  34 /**
  35  * Determine correct target name flags for reply, given server role
  36  * and negotiated flags
  37  *
  38  * @param ntlmssp_state NTLMSSP State
  39  * @param neg_flags The flags from the packet
  40  * @param chal_flags The flags to be set in the reply packet
  41  * @return The 'target name' string.
  42  */
  43
  44 const char *ntlmssp_target_name(struct ntlmssp_state *ntlmssp_state,
  45                                 uint32_t neg_flags, uint32_t *chal_flags)
  46 {
  47         if (neg_flags & NTLMSSP_REQUEST_TARGET) {
  48                 *chal_flags |= NTLMSSP_NEGOTIATE_TARGET_INFO;
  49                 *chal_flags |= NTLMSSP_REQUEST_TARGET;
  50                 if (ntlmssp_state->server.is_standalone) {
  51                         *chal_flags |= NTLMSSP_TARGET_TYPE_SERVER;
  52                         return ntlmssp_state->server.netbios_name;
  53                 } else {
  54                         *chal_flags |= NTLMSSP_TARGET_TYPE_DOMAIN;
  55                         return ntlmssp_state->server.netbios_domain;
  56                 };
  57         } else {
  58                 return "";
  59         }
  60 }
  61
  62 /**
  63  * Next state function for the NTLMSSP Negotiate packet
  64  *
  65  * @param gensec_security GENSEC state
  66  * @param out_mem_ctx Memory context for *out
  67  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
  68  * @param out The reply, as an allocated DATA_BLOB, caller to free.
  69  * @return Errors or MORE_PROCESSING_REQUIRED if (normal) a reply is required.
  70  */
  71
  72 NTSTATUS gensec_ntlmssp_server_negotiate(struct gensec_security *gensec_security,
  73                                          TALLOC_CTX *out_mem_ctx,
  74                                          const DATA_BLOB request, DATA_BLOB *reply)
  75 {
  76         struct gensec_ntlmssp_context *gensec_ntlmssp =
  77                 talloc_get_type_abort(gensec_security->private_data,
  78                                       struct gensec_ntlmssp_context);
  79         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
  80         struct auth4_context *auth_context = gensec_security->auth_context;
  81         DATA_BLOB struct_blob;
  82         uint32_t neg_flags = 0;
  83         uint32_t ntlmssp_command, chal_flags;
  84         uint8_t cryptkey[8];
  85         const char *target_name;
  86         NTSTATUS status;
  87
  88         /* parse the NTLMSSP packet */
  89 #if 0
  90         file_save("ntlmssp_negotiate.dat", request.data, request.length);
  91 #endif
  92
  93         if (request.length) {
  94                 if ((request.length < 16) || !msrpc_parse(ntlmssp_state, &request, "Cdd",
  95                                                           "NTLMSSP",
  96                                                           &ntlmssp_command,
  97                                                           &neg_flags)) {
  98                         DEBUG(1, ("ntlmssp_server_negotiate: failed to parse NTLMSSP Negotiate of length %u\n",
  99                                 (unsigned int)request.length));
 100                         dump_data(2, request.data, request.length);
 101                         return NT_STATUS_INVALID_PARAMETER;
 102                 }
 103                 debug_ntlmssp_flags(neg_flags);
 104
 105                 if (DEBUGLEVEL >= 10) {
 106                         struct NEGOTIATE_MESSAGE *negotiate = talloc(
 107                                 ntlmssp_state, struct NEGOTIATE_MESSAGE);
 108                         if (negotiate != NULL) {
 109                                 status = ntlmssp_pull_NEGOTIATE_MESSAGE(
 110                                         &request, negotiate, negotiate);
 111                                 if (NT_STATUS_IS_OK(status)) {
 112                                         NDR_PRINT_DEBUG(NEGOTIATE_MESSAGE,
 113                                                         negotiate);
 114                                 }
 115                                 TALLOC_FREE(negotiate);
 116                         }
 117                 }
 118         }
 119
 120         ntlmssp_handle_neg_flags(ntlmssp_state, neg_flags, ntlmssp_state->allow_lm_key);
 121
 122         /* Ask our caller what challenge they would like in the packet */
 123         if (auth_context->get_ntlm_challenge) {
 124                 status = auth_context->get_ntlm_challenge(auth_context, cryptkey);
 125                 if (!NT_STATUS_IS_OK(status)) {
 126                         DEBUG(1, ("gensec_ntlmssp_server_negotiate: failed to get challenge: %s\n",
 127                                   nt_errstr(status)));
 128                         return status;
 129                 }
 130         } else {
 131                 DEBUG(1, ("gensec_ntlmssp_server_negotiate: backend doesn't give a challenge\n"));
 132                 return NT_STATUS_NOT_IMPLEMENTED;
 133         }
 134
 135         /* The flags we send back are not just the negotiated flags,
 136          * they are also 'what is in this packet'.  Therfore, we
 137          * operate on 'chal_flags' from here on
 138          */
 139
 140         chal_flags = ntlmssp_state->neg_flags;
 141
 142         /* get the right name to fill in as 'target' */
 143         target_name = ntlmssp_target_name(ntlmssp_state,
 144                                           neg_flags, &chal_flags);
 145         if (target_name == NULL)
 146                 return NT_STATUS_INVALID_PARAMETER;
 147
 148         ntlmssp_state->chal = data_blob_talloc(ntlmssp_state, cryptkey, 8);
 149         ntlmssp_state->internal_chal = data_blob_talloc(ntlmssp_state,
 150                                                         cryptkey, 8);
 151
 152         /* This creates the 'blob' of names that appears at the end of the packet */
 153         if (chal_flags & NTLMSSP_NEGOTIATE_TARGET_INFO)
 154         {
 155                 status = msrpc_gen(ntlmssp_state, &struct_blob, "aaaaa",
 156                           MsvAvNbDomainName, target_name,
 157                           MsvAvNbComputerName, ntlmssp_state->server.netbios_name,
 158                           MsvAvDnsDomainName, ntlmssp_state->server.dns_domain,
 159                           MsvAvDnsComputerName, ntlmssp_state->server.dns_name,
 160                           MsvAvEOL, "");
 161                 if (!NT_STATUS_IS_OK(status)) {
 162                         return status;
 163                 }
 164         } else {
 165                 struct_blob = data_blob_null;
 166         }
 167
 168         {
 169                 /* Marshal the packet in the right format, be it unicode or ASCII */
 170                 const char *gen_string;
 171                 const DATA_BLOB version_blob = ntlmssp_version_blob();
 172
 173                 if (ntlmssp_state->unicode) {
 174                         gen_string = "CdUdbddBb";
 175                 } else {
 176                         gen_string = "CdAdbddBb";
 177                 }
 178
 179                 status = msrpc_gen(out_mem_ctx, reply, gen_string,
 180                         "NTLMSSP",
 181                         NTLMSSP_CHALLENGE,
 182                         target_name,
 183                         chal_flags,
 184                         cryptkey, 8,
 185                         0, 0,
 186                         struct_blob.data, struct_blob.length,
 187                         version_blob.data, version_blob.length);
 188
 189                 if (!NT_STATUS_IS_OK(status)) {
 190                         data_blob_free(&struct_blob);
 191                         return status;
 192                 }
 193
 194                 if (DEBUGLEVEL >= 10) {
 195                         struct CHALLENGE_MESSAGE *challenge = talloc(
 196                                 ntlmssp_state, struct CHALLENGE_MESSAGE);
 197                         if (challenge != NULL) {
 198                                 challenge->NegotiateFlags = chal_flags;
 199                                 status = ntlmssp_pull_CHALLENGE_MESSAGE(
 200                                         reply, challenge, challenge);
 201                                 if (NT_STATUS_IS_OK(status)) {
 202                                         NDR_PRINT_DEBUG(CHALLENGE_MESSAGE,
 203                                                         challenge);
 204                                 }
 205                                 TALLOC_FREE(challenge);
 206                         }
 207                 }
 208         }
 209
 210         data_blob_free(&struct_blob);
 211
 212         ntlmssp_state->expected_state = NTLMSSP_AUTH;
 213
 214         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 215 }
 216
 217 struct ntlmssp_server_auth_state {
 218         DATA_BLOB user_session_key;
 219         DATA_BLOB lm_session_key;
 220         /* internal variables used by KEY_EXCH (client-supplied user session key */
 221         DATA_BLOB encrypted_session_key;
 222         bool doing_ntlm2;
 223         /* internal variables used by NTLM2 */
 224         uint8_t session_nonce[16];
 225 };
 226
 227 /**
 228  * Next state function for the Authenticate packet
 229  *
 230  * @param ntlmssp_state NTLMSSP State
 231  * @param request The request, as a DATA_BLOB
 232  * @return Errors or NT_STATUS_OK.
 233  */
 234
 235 static NTSTATUS ntlmssp_server_preauth(struct gensec_security *gensec_security,
 236                                        struct gensec_ntlmssp_context *gensec_ntlmssp,
 237                                        struct ntlmssp_server_auth_state *state,
 238                                        const DATA_BLOB request)
 239 {
 240         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 241         struct auth4_context *auth_context = gensec_security->auth_context;
 242         uint32_t ntlmssp_command, auth_flags;
 243         NTSTATUS nt_status;
 244
 245         uint8_t session_nonce_hash[16];
 246
 247         const char *parse_string;
 248
 249 #if 0
 250         file_save("ntlmssp_auth.dat", request.data, request.length);
 251 #endif
 252
 253         if (ntlmssp_state->unicode) {
 254                 parse_string = "CdBBUUUBd";
 255         } else {
 256                 parse_string = "CdBBAAABd";
 257         }
 258
 259         /* zero these out */
 260         data_blob_free(&ntlmssp_state->session_key);
 261         data_blob_free(&ntlmssp_state->lm_resp);
 262         data_blob_free(&ntlmssp_state->nt_resp);
 263
 264         ntlmssp_state->user = NULL;
 265         ntlmssp_state->domain = NULL;
 266         ntlmssp_state->client.netbios_name = NULL;
 267
 268         /* now the NTLMSSP encoded auth hashes */
 269         if (!msrpc_parse(ntlmssp_state, &request, parse_string,
 270                          "NTLMSSP",
 271                          &ntlmssp_command,
 272                          &ntlmssp_state->lm_resp,
 273                          &ntlmssp_state->nt_resp,
 274                          &ntlmssp_state->domain,
 275                          &ntlmssp_state->user,
 276                          &ntlmssp_state->client.netbios_name,
 277                          &state->encrypted_session_key,
 278                          &auth_flags)) {
 279                 DEBUG(10, ("ntlmssp_server_auth: failed to parse NTLMSSP (nonfatal):\n"));
 280                 dump_data(10, request.data, request.length);
 281
 282                 /* zero this out */
 283                 data_blob_free(&state->encrypted_session_key);
 284                 auth_flags = 0;
 285
 286                 /* Try again with a shorter string (Win9X truncates this packet) */
 287                 if (ntlmssp_state->unicode) {
 288                         parse_string = "CdBBUUU";
 289                 } else {
 290                         parse_string = "CdBBAAA";
 291                 }
 292
 293                 /* now the NTLMSSP encoded auth hashes */
 294                 if (!msrpc_parse(ntlmssp_state, &request, parse_string,
 295                                  "NTLMSSP",
 296                                  &ntlmssp_command,
 297                                  &ntlmssp_state->lm_resp,
 298                                  &ntlmssp_state->nt_resp,
 299                                  &ntlmssp_state->domain,
 300                                  &ntlmssp_state->user,
 301                                  &ntlmssp_state->client.netbios_name)) {
 302                         DEBUG(1, ("ntlmssp_server_auth: failed to parse NTLMSSP (tried both formats):\n"));
 303                         dump_data(2, request.data, request.length);
 304
 305                         return NT_STATUS_INVALID_PARAMETER;
 306                 }
 307         }
 308
 309         talloc_steal(state, state->encrypted_session_key.data);
 310
 311         if (auth_flags)
 312                 ntlmssp_handle_neg_flags(ntlmssp_state, auth_flags, ntlmssp_state->allow_lm_key);
 313
 314         if (DEBUGLEVEL >= 10) {
 315                 struct AUTHENTICATE_MESSAGE *authenticate = talloc(
 316                         ntlmssp_state, struct AUTHENTICATE_MESSAGE);
 317                 if (authenticate != NULL) {
 318                         NTSTATUS status;
 319                         authenticate->NegotiateFlags = auth_flags;
 320                         status = ntlmssp_pull_AUTHENTICATE_MESSAGE(
 321                                 &request, authenticate, authenticate);
 322                         if (NT_STATUS_IS_OK(status)) {
 323                                 NDR_PRINT_DEBUG(AUTHENTICATE_MESSAGE,
 324                                                 authenticate);
 325                         }
 326                         TALLOC_FREE(authenticate);
 327                 }
 328         }
 329
 330         DEBUG(3,("Got user=[%s] domain=[%s] workstation=[%s] len1=%lu len2=%lu\n",
 331                  ntlmssp_state->user, ntlmssp_state->domain,
 332                  ntlmssp_state->client.netbios_name,
 333                  (unsigned long)ntlmssp_state->lm_resp.length,
 334                  (unsigned long)ntlmssp_state->nt_resp.length));
 335
 336 #if 0
 337         file_save("nthash1.dat",  &ntlmssp_state->nt_resp.data,  &ntlmssp_state->nt_resp.length);
 338         file_save("lmhash1.dat",  &ntlmssp_state->lm_resp.data,  &ntlmssp_state->lm_resp.length);
 339 #endif
 340
 341         /* NTLM2 uses a 'challenge' that is made of up both the server challenge, and a
 342            client challenge
 343
 344            However, the NTLM2 flag may still be set for the real NTLMv2 logins, be careful.
 345         */
 346         if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
 347                 if (ntlmssp_state->nt_resp.length == 24 && ntlmssp_state->lm_resp.length == 24) {
 348                         MD5_CTX md5_session_nonce_ctx;
 349                         state->doing_ntlm2 = true;
 350
 351                         memcpy(state->session_nonce, ntlmssp_state->internal_chal.data, 8);
 352                         memcpy(&state->session_nonce[8], ntlmssp_state->lm_resp.data, 8);
 353
 354                         SMB_ASSERT(ntlmssp_state->internal_chal.data && ntlmssp_state->internal_chal.length == 8);
 355
 356                         MD5Init(&md5_session_nonce_ctx);
 357                         MD5Update(&md5_session_nonce_ctx, state->session_nonce, 16);
 358                         MD5Final(session_nonce_hash, &md5_session_nonce_ctx);
 359
 360                         /* LM response is no longer useful */
 361                         data_blob_free(&ntlmssp_state->lm_resp);
 362
 363                         /* We changed the effective challenge - set it */
 364                         if (auth_context->set_ntlm_challenge) {
 365                                 nt_status = auth_context->set_ntlm_challenge(auth_context,
 366                                                                              session_nonce_hash,
 367                                                                              "NTLMSSP callback (NTLM2)");
 368                                 if (!NT_STATUS_IS_OK(nt_status)) {
 369                                         DEBUG(1, ("gensec_ntlmssp_server_negotiate: failed to get challenge: %s\n",
 370                                                   nt_errstr(nt_status)));
 371                                         return nt_status;
 372                                 }
 373                         } else {
 374                                 DEBUG(1, ("gensec_ntlmssp_server_negotiate: backend doesn't have facility for challenge to be set\n"));
 375
 376                                 return NT_STATUS_NOT_IMPLEMENTED;
 377                         }
 378
 379                         /* LM Key is incompatible. */
 380                         ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 381                 }
 382         }
 383         return NT_STATUS_OK;
 384 }
 385
 386 /**
 387  * Check the password on an NTLMSSP login.
 388  *
 389  * Return the session keys used on the connection.
 390  */
 391
 392 static NTSTATUS ntlmssp_server_check_password(struct gensec_security *gensec_security,
 393                                               struct gensec_ntlmssp_context *gensec_ntlmssp,
 394                                               TALLOC_CTX *mem_ctx,
 395                                               DATA_BLOB *user_session_key, DATA_BLOB *lm_session_key)
 396 {
 397         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 398         struct auth4_context *auth_context = gensec_security->auth_context;
 399         NTSTATUS nt_status = NT_STATUS_NOT_IMPLEMENTED;
 400         struct auth_usersupplied_info *user_info;
 401
 402         user_info = talloc_zero(ntlmssp_state, struct auth_usersupplied_info);
 403         if (!user_info) {
 404                 return NT_STATUS_NO_MEMORY;
 405         }
 406
 407         user_info->logon_parameters = MSV1_0_ALLOW_SERVER_TRUST_ACCOUNT | MSV1_0_ALLOW_WORKSTATION_TRUST_ACCOUNT;
 408         user_info->flags = 0;
 409         user_info->mapped_state = false;
 410         user_info->client.account_name = ntlmssp_state->user;
 411         user_info->client.domain_name = ntlmssp_state->domain;
 412         user_info->workstation_name = ntlmssp_state->client.netbios_name;
 413         user_info->remote_host = gensec_get_remote_address(gensec_security);
 414
 415         user_info->password_state = AUTH_PASSWORD_RESPONSE;
 416         user_info->password.response.lanman = ntlmssp_state->lm_resp;
 417         user_info->password.response.lanman.data = talloc_steal(user_info, ntlmssp_state->lm_resp.data);
 418         user_info->password.response.nt = ntlmssp_state->nt_resp;
 419         user_info->password.response.nt.data = talloc_steal(user_info, ntlmssp_state->nt_resp.data);
 420
 421         if (auth_context->check_ntlm_password) {
 422                 nt_status = auth_context->check_ntlm_password(auth_context,
 423                                                               gensec_ntlmssp,
 424                                                               user_info,
 425                                                               &gensec_ntlmssp->server_returned_info,
 426                                                               user_session_key, lm_session_key);
 427         }
 428
 429         if (!NT_STATUS_IS_OK(nt_status)) {
 430                 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)));
 431         }
 432         TALLOC_FREE(user_info);
 433
 434         NT_STATUS_NOT_OK_RETURN(nt_status);
 435
 436         talloc_steal(mem_ctx, user_session_key->data);
 437         talloc_steal(mem_ctx, lm_session_key->data);
 438
 439         return nt_status;
 440 }
 441
 442 /**
 443  * Next state function for the Authenticate packet
 444  * (after authentication - figures out the session keys etc)
 445  *
 446  * @param ntlmssp_state NTLMSSP State
 447  * @return Errors or NT_STATUS_OK.
 448  */
 449
 450 static NTSTATUS ntlmssp_server_postauth(struct gensec_security *gensec_security,
 451                                         struct gensec_ntlmssp_context *gensec_ntlmssp,
 452                                         struct ntlmssp_server_auth_state *state)
 453 {
 454         struct ntlmssp_state *ntlmssp_state = gensec_ntlmssp->ntlmssp_state;
 455         DATA_BLOB user_session_key = state->user_session_key;
 456         DATA_BLOB lm_session_key = state->lm_session_key;
 457         NTSTATUS nt_status = NT_STATUS_OK;
 458         DATA_BLOB session_key = data_blob(NULL, 0);
 459
 460         dump_data_pw("NT session key:\n", user_session_key.data, user_session_key.length);
 461         dump_data_pw("LM first-8:\n", lm_session_key.data, lm_session_key.length);
 462
 463         /* Handle the different session key derivation for NTLM2 */
 464         if (state->doing_ntlm2) {
 465                 if (user_session_key.data && user_session_key.length == 16) {
 466                         session_key = data_blob_talloc(ntlmssp_state,
 467                                                        NULL, 16);
 468                         hmac_md5(user_session_key.data, state->session_nonce,
 469                                  sizeof(state->session_nonce), session_key.data);
 470                         DEBUG(10,("ntlmssp_server_auth: Created NTLM2 session key.\n"));
 471                         dump_data_pw("NTLM2 session key:\n", session_key.data, session_key.length);
 472
 473                 } else {
 474                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM2 session key.\n"));
 475                         session_key = data_blob_null;
 476                 }
 477         } else if ((ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
 478                 /* Ensure we can never get here on NTLMv2 */
 479                 && (ntlmssp_state->nt_resp.length == 0 || ntlmssp_state->nt_resp.length == 24)) {
 480
 481                 if (lm_session_key.data && lm_session_key.length >= 8) {
 482                         if (ntlmssp_state->lm_resp.data && ntlmssp_state->lm_resp.length == 24) {
 483                                 session_key = data_blob_talloc(ntlmssp_state,
 484                                                                NULL, 16);
 485                                 if (session_key.data == NULL) {
 486                                         return NT_STATUS_NO_MEMORY;
 487                                 }
 488                                 SMBsesskeygen_lm_sess_key(lm_session_key.data, ntlmssp_state->lm_resp.data,
 489                                                           session_key.data);
 490                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 491                         } else {
 492                                 static const uint8_t zeros[24] = {0, };
 493                                 session_key = data_blob_talloc(
 494                                         ntlmssp_state, NULL, 16);
 495                                 if (session_key.data == NULL) {
 496                                         return NT_STATUS_NO_MEMORY;
 497                                 }
 498                                 SMBsesskeygen_lm_sess_key(zeros, zeros,
 499                                                           session_key.data);
 500                                 DEBUG(10,("ntlmssp_server_auth: Created NTLM session key.\n"));
 501                         }
 502                         dump_data_pw("LM session key:\n", session_key.data,
 503                                      session_key.length);
 504                 } else {
 505                         /* LM Key not selected */
 506                         ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 507
 508                         DEBUG(10,("ntlmssp_server_auth: Failed to create NTLM session key.\n"));
 509                         session_key = data_blob_null;
 510                 }
 511
 512         } else if (user_session_key.data) {
 513                 session_key = user_session_key;
 514                 DEBUG(10,("ntlmssp_server_auth: Using unmodified nt session key.\n"));
 515                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 516
 517                 /* LM Key not selected */
 518                 ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 519
 520         } else if (lm_session_key.data) {
 521                 /* Very weird to have LM key, but no user session key, but anyway.. */
 522                 session_key = lm_session_key;
 523                 DEBUG(10,("ntlmssp_server_auth: Using unmodified lm session key.\n"));
 524                 dump_data_pw("unmodified session key:\n", session_key.data, session_key.length);
 525
 526                 /* LM Key not selected */
 527                 ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 528
 529         } else {
 530                 DEBUG(10,("ntlmssp_server_auth: Failed to create unmodified session key.\n"));
 531                 session_key = data_blob_null;
 532
 533                 /* LM Key not selected */
 534                 ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
 535         }
 536
 537         /* With KEY_EXCH, the client supplies the proposed session key,
 538            but encrypts it with the long-term key */
 539         if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
 540                 if (!state->encrypted_session_key.data
 541                     || state->encrypted_session_key.length != 16) {
 542                         DEBUG(1, ("Client-supplied KEY_EXCH session key was of invalid length (%u)!\n",
 543                                   (unsigned)state->encrypted_session_key.length));
 544                         return NT_STATUS_INVALID_PARAMETER;
 545                 } else if (!session_key.data || session_key.length != 16) {
 546                         DEBUG(5, ("server session key is invalid (len == %u), cannot do KEY_EXCH!\n",
 547                                   (unsigned int)session_key.length));
 548                         ntlmssp_state->session_key = session_key;
 549                         talloc_steal(ntlmssp_state, session_key.data);
 550                 } else {
 551                         dump_data_pw("KEY_EXCH session key (enc):\n",
 552                                      state->encrypted_session_key.data,
 553                                      state->encrypted_session_key.length);
 554                         arcfour_crypt(state->encrypted_session_key.data,
 555                                       session_key.data,
 556                                       state->encrypted_session_key.length);
 557                         ntlmssp_state->session_key = data_blob_talloc(ntlmssp_state,
 558                                                                       state->encrypted_session_key.data,
 559                                                                       state->encrypted_session_key.length);
 560                         dump_data_pw("KEY_EXCH session key:\n",
 561                                      state->encrypted_session_key.data,
 562                                      state->encrypted_session_key.length);
 563                 }
 564         } else {
 565                 ntlmssp_state->session_key = session_key;
 566                 talloc_steal(ntlmssp_state, session_key.data);
 567         }
 568
 569         if (ntlmssp_state->session_key.length) {
 570                 nt_status = ntlmssp_sign_init(ntlmssp_state);
 571         }
 572
 573         ntlmssp_state->expected_state = NTLMSSP_DONE;
 574
 575         return nt_status;
 576 }
 577
 578
 579 /**
 580  * Next state function for the NTLMSSP Authenticate packet
 581  *
 582  * @param gensec_security GENSEC state
 583  * @param out_mem_ctx Memory context for *out
 584  * @param in The request, as a DATA_BLOB.  reply.data must be NULL
 585  * @param out The reply, as an allocated DATA_BLOB, caller to free.
 586  * @return Errors or NT_STATUS_OK if authentication sucessful
 587  */
 588
 589 NTSTATUS gensec_ntlmssp_server_auth(struct gensec_security *gensec_security,
 590                                     TALLOC_CTX *out_mem_ctx,
 591                                     const DATA_BLOB in, DATA_BLOB *out)
 592 {
 593         struct gensec_ntlmssp_context *gensec_ntlmssp =
 594                 talloc_get_type_abort(gensec_security->private_data,
 595                                       struct gensec_ntlmssp_context);
 596         struct ntlmssp_server_auth_state *state;
 597         NTSTATUS nt_status;
 598
 599         /* zero the outbound NTLMSSP packet */
 600         *out = data_blob_null;
 601
 602         state = talloc_zero(gensec_ntlmssp, struct ntlmssp_server_auth_state);
 603         if (state == NULL) {
 604                 return NT_STATUS_NO_MEMORY;
 605         }
 606
 607         nt_status = ntlmssp_server_preauth(gensec_security, gensec_ntlmssp, state, in);
 608         if (!NT_STATUS_IS_OK(nt_status)) {
 609                 TALLOC_FREE(state);
 610                 return nt_status;
 611         }
 612
 613         /*
 614          * Note we don't check here for NTLMv2 auth settings. If NTLMv2 auth
 615          * is required (by "ntlm auth = no" and "lm auth = no" being set in the
 616          * smb.conf file) and no NTLMv2 response was sent then the password check
 617          * will fail here. JRA.
 618          */
 619
 620         /* Finally, actually ask if the password is OK */
 621         nt_status = ntlmssp_server_check_password(gensec_security, gensec_ntlmssp,
 622                                                   state,
 623                                                   &state->user_session_key,
 624                                                   &state->lm_session_key);
 625         if (!NT_STATUS_IS_OK(nt_status)) {
 626                 TALLOC_FREE(state);
 627                 return nt_status;
 628         }
 629
 630         /* When we get more async in the auth code behind
 631            ntlmssp_state->check_password, the ntlmssp_server_postpath
 632            can be done in a callback */
 633
 634         nt_status = ntlmssp_server_postauth(gensec_security, gensec_ntlmssp, state);
 635         TALLOC_FREE(state);
 636         return nt_status;
 637 }