source/libcli/auth/spnego.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    RFC2478 Compliant SPNEGO implementation
   5
   6    Copyright (C) Jim McDonough <jmcd@us.ibm.com>      2003
   7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004
   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 2 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
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23 */
  24
  25 #include "includes.h"
  26
  27 #undef DBGC_CLASS
  28 #define DBGC_CLASS DBGC_AUTH
  29
  30 enum spnego_state_position {
  31         SPNEGO_SERVER_START,
  32         SPNEGO_CLIENT_START,
  33         SPNEGO_SERVER_TARG,
  34         SPNEGO_CLIENT_TARG,
  35         SPNEGO_FALLBACK,
  36         SPNEGO_DONE
  37 };
  38
  39 struct spnego_state {
  40         TALLOC_CTX *mem_ctx;
  41         uint_t ref_count;
  42         enum spnego_message_type expected_packet;
  43         enum spnego_state_position state_position;
  44         struct gensec_security *sub_sec_security;
  45 };
  46
  47 static NTSTATUS gensec_spnego_client_start(struct gensec_security *gensec_security)
  48 {
  49         struct spnego_state *spnego_state;
  50         TALLOC_CTX *mem_ctx = talloc_init("gensec_spnego_client_start");
  51         if (!mem_ctx) {
  52                 return NT_STATUS_NO_MEMORY;
  53         }
  54         spnego_state = talloc_p(mem_ctx, struct spnego_state);
  55
  56         if (!spnego_state) {
  57                 return NT_STATUS_NO_MEMORY;
  58         }
  59
  60         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_INIT;
  61         spnego_state->state_position = SPNEGO_CLIENT_START;
  62         spnego_state->mem_ctx = mem_ctx;
  63         spnego_state->sub_sec_security = NULL;
  64
  65         gensec_security->private_data = spnego_state;
  66         return NT_STATUS_OK;
  67 }
  68
  69 /*
  70   wrappers for the spnego_*() functions
  71 */
  72 static NTSTATUS gensec_spnego_unseal_packet(struct gensec_security *gensec_security,
  73                                      TALLOC_CTX *mem_ctx,
  74                                      uint8_t *data, size_t length, DATA_BLOB *sig)
  75 {
  76         struct spnego_state *spnego_state = gensec_security->private_data;
  77
  78         if (spnego_state->state_position != SPNEGO_DONE
  79             && spnego_state->state_position != SPNEGO_FALLBACK) {
  80                 return NT_STATUS_INVALID_PARAMETER;
  81         }
  82
  83         return gensec_unseal_packet(spnego_state->sub_sec_security,
  84                                     mem_ctx, data, length, sig);
  85 }
  86
  87 static NTSTATUS gensec_spnego_check_packet(struct gensec_security *gensec_security,
  88                                      TALLOC_CTX *mem_ctx,
  89                                      const uint8_t *data, size_t length,
  90                                      const DATA_BLOB *sig)
  91 {
  92         struct spnego_state *spnego_state = gensec_security->private_data;
  93
  94         return NT_STATUS_NOT_IMPLEMENTED;
  95         if (spnego_state->state_position != SPNEGO_DONE
  96             && spnego_state->state_position != SPNEGO_FALLBACK) {
  97                 return NT_STATUS_INVALID_PARAMETER;
  98         }
  99
 100         return gensec_check_packet(spnego_state->sub_sec_security,
 101                                 mem_ctx, data, length, sig);
 102 }
 103
 104 static NTSTATUS gensec_spnego_seal_packet(struct gensec_security *gensec_security,
 105                                     TALLOC_CTX *mem_ctx,
 106                                     uint8_t *data, size_t length,
 107                                     DATA_BLOB *sig)
 108 {
 109         struct spnego_state *spnego_state = gensec_security->private_data;
 110
 111         return NT_STATUS_NOT_IMPLEMENTED;
 112         if (spnego_state->state_position != SPNEGO_DONE
 113             && spnego_state->state_position != SPNEGO_FALLBACK) {
 114                 return NT_STATUS_INVALID_PARAMETER;
 115         }
 116
 117         return gensec_seal_packet(spnego_state->sub_sec_security,
 118                                   mem_ctx, data, length, sig);
 119 }
 120
 121 static NTSTATUS gensec_spnego_sign_packet(struct gensec_security *gensec_security,
 122                                     TALLOC_CTX *mem_ctx,
 123                                     const uint8_t *data, size_t length,
 124                                     DATA_BLOB *sig)
 125 {
 126         struct spnego_state *spnego_state = gensec_security->private_data;
 127
 128         if (spnego_state->state_position != SPNEGO_DONE
 129             && spnego_state->state_position != SPNEGO_FALLBACK) {
 130                 return NT_STATUS_INVALID_PARAMETER;
 131         }
 132
 133         return gensec_sign_packet(spnego_state->sub_sec_security,
 134                                   mem_ctx, data, length, sig);
 135 }
 136
 137 static NTSTATUS gensec_spnego_session_key(struct gensec_security *gensec_security,
 138                                     DATA_BLOB *session_key)
 139 {
 140         struct spnego_state *spnego_state = gensec_security->private_data;
 141         if (!spnego_state->sub_sec_security) {
 142                 return NT_STATUS_INVALID_PARAMETER;
 143         }
 144
 145         return gensec_session_key(spnego_state->sub_sec_security,
 146                                   session_key);
 147 }
 148
 149 /** Fallback to another GENSEC mechanism, based on magic strings
 150  *
 151  * This is the 'fallback' case, where we don't get SPNEGO, and have to
 152  * try all the other options (and hope they all have a magic string
 153  * they check)
 154 */
 155
 156 static NTSTATUS gensec_spnego_server_try_fallback(struct gensec_security *gensec_security,
 157                                                   struct spnego_state *spnego_state,
 158                                                   TALLOC_CTX *out_mem_ctx,
 159                                                   const DATA_BLOB in, DATA_BLOB *out)
 160 {
 161         int i;
 162         int num_ops;
 163         const struct gensec_security_ops **all_ops = gensec_security_all(&num_ops);
 164         for (i=0; i < num_ops; i++) {
 165                 NTSTATUS nt_status;
 166                 if (!all_ops[i]->oid) {
 167                         continue;
 168                 }
 169                 nt_status = gensec_subcontext_start(gensec_security,
 170                                                     &spnego_state->sub_sec_security);
 171                 if (!NT_STATUS_IS_OK(nt_status)) {
 172                         return nt_status;
 173                 }
 174                 /* select the sub context */
 175                 nt_status = gensec_start_mech_by_oid(spnego_state->sub_sec_security,
 176                                                      all_ops[i]->oid);
 177                 if (!NT_STATUS_IS_OK(nt_status)) {
 178                         gensec_end(&spnego_state->sub_sec_security);
 179                                         continue;
 180                 }
 181                 nt_status = gensec_update(spnego_state->sub_sec_security,
 182                                                           out_mem_ctx, in, out);
 183                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 184                         spnego_state->state_position = SPNEGO_FALLBACK;
 185                         return nt_status;
 186                 }
 187                 gensec_end(&spnego_state->sub_sec_security);
 188         }
 189         DEBUG(1, ("Failed to parse SPNEGO request\n"));
 190         return NT_STATUS_INVALID_PARAMETER;
 191
 192 }
 193
 194 /** create a client netTokenInit
 195  *
 196  * This is the case, where the client is the first one who sends data
 197 */
 198
 199 static NTSTATUS gensec_spnego_client_netTokenInit(struct gensec_security *gensec_security,
 200                                                   struct spnego_state *spnego_state,
 201                                                   TALLOC_CTX *out_mem_ctx,
 202                                                   const DATA_BLOB in, DATA_BLOB *out)
 203 {
 204         NTSTATUS nt_status;
 205         int i;
 206         int num_ops;
 207         char **mechTypes = NULL;
 208         const struct gensec_security_ops **all_ops = gensec_security_all(&num_ops);
 209         DATA_BLOB null_data_blob = data_blob(NULL,0);
 210         DATA_BLOB unwrapped_out = data_blob(NULL,0);
 211
 212         if (num_ops < 1) {
 213                 DEBUG(1, ("no GENSEC backends available\n"));
 214                 return NT_STATUS_INVALID_PARAMETER;
 215         }
 216
 217         /* build a mechTypes list we want to offer */
 218         for (i=0; i < num_ops; i++) {
 219                 if (!all_ops[i]->oid) {
 220                         continue;
 221                 }
 222
 223                 /* skip SPNEGO itself */
 224                 if (strcmp(OID_SPNEGO,all_ops[i]->oid)==0) {
 225                         continue;
 226                 }
 227
 228                 mechTypes = talloc_realloc_p(out_mem_ctx, mechTypes, char *, i+2);
 229                 if (!mechTypes) {
 230                         DEBUG(1, ("talloc_realloc_p(out_mem_ctx, mechTypes, char *, i+1) failed\n"));
 231                         return NT_STATUS_NO_MEMORY;
 232                 }
 233
 234                 mechTypes[i] = all_ops[i]->oid;
 235                 mechTypes[i+1] = NULL;
 236         }
 237
 238         if (!mechTypes) {
 239                 DEBUG(1, ("no GENSEC OID backends available\n"));
 240                 return NT_STATUS_INVALID_PARAMETER;
 241         }
 242
 243         nt_status = gensec_subcontext_start(gensec_security,
 244                                             &spnego_state->sub_sec_security);
 245         if (!NT_STATUS_IS_OK(nt_status)) {
 246                 return nt_status;
 247         }
 248         /* select our preferred mech */
 249         nt_status = gensec_start_mech_by_oid(spnego_state->sub_sec_security,
 250                                              mechTypes[0]);
 251         if (!NT_STATUS_IS_OK(nt_status)) {
 252                 gensec_end(&spnego_state->sub_sec_security);
 253                         return nt_status;
 254         }
 255         nt_status = gensec_update(spnego_state->sub_sec_security,
 256                                   out_mem_ctx, in, &unwrapped_out);
 257         if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 258                 struct spnego_data spnego_out;
 259                 spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 260                 spnego_out.negTokenInit.mechTypes = mechTypes;
 261                 spnego_out.negTokenInit.reqFlags = 0;
 262                 spnego_out.negTokenInit.mechListMIC = null_data_blob;
 263                 spnego_out.negTokenInit.mechToken = unwrapped_out;
 264
 265                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 266                         DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_INIT\n"));
 267                                 return NT_STATUS_INVALID_PARAMETER;
 268                 }
 269
 270                 /* set next state */
 271                 spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 272                 spnego_state->state_position = SPNEGO_CLIENT_TARG;
 273                 return nt_status;
 274         }
 275         gensec_end(&spnego_state->sub_sec_security);
 276
 277         DEBUG(1, ("Failed to setup SPNEGO netTokenInit request\n"));
 278         return NT_STATUS_INVALID_PARAMETER;
 279 }
 280
 281 static NTSTATUS gensec_spnego_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx,
 282                                const DATA_BLOB in, DATA_BLOB *out)
 283 {
 284         struct spnego_state *spnego_state = gensec_security->private_data;
 285         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 286         DATA_BLOB unwrapped_out = data_blob(NULL, 0);
 287         struct spnego_data spnego_out;
 288         struct spnego_data spnego;
 289
 290         ssize_t len;
 291
 292         if (!out_mem_ctx) {
 293                 out_mem_ctx = spnego_state->mem_ctx;
 294         }
 295
 296         /* and switch into the state machine */
 297
 298         switch (spnego_state->state_position) {
 299         case SPNEGO_FALLBACK:
 300                 return gensec_update(spnego_state->sub_sec_security,
 301                                      out_mem_ctx, in, out);
 302         case SPNEGO_SERVER_START:
 303         {
 304                 if (in.length) {
 305                         len = spnego_read_data(in, &spnego);
 306                         if (len == -1) {
 307                                 return gensec_spnego_server_try_fallback(gensec_security, spnego_state, out_mem_ctx, in, out);
 308                         } else {
 309                                 /* client sent NegTargetInit */
 310                         }
 311                 } else {
 312                         /* server needs to send NegTargetInit */
 313                 }
 314                 return NT_STATUS_INVALID_PARAMETER;
 315         }
 316
 317         case SPNEGO_CLIENT_START:
 318         {
 319                 /* The server offers a list of mechanisms */
 320
 321                 char **mechType;
 322                 char *my_mechs[] = {NULL, NULL};
 323                 int i;
 324                 NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 325
 326                 if (!in.length) {
 327                         /* client to produce negTokenInit */
 328                         return gensec_spnego_client_netTokenInit(gensec_security, spnego_state, out_mem_ctx, in, out);
 329                 }
 330
 331                 len = spnego_read_data(in, &spnego);
 332
 333                 if (len == -1) {
 334                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 335                         dump_data(1, (const char *)in.data, in.length);
 336                         return NT_STATUS_INVALID_PARAMETER;
 337                 }
 338
 339                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 340                 if (spnego.type != spnego_state->expected_packet) {
 341                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 342                                   spnego_state->expected_packet));
 343                         dump_data(1, (const char *)in.data, in.length);
 344                         spnego_free_data(&spnego);
 345                         return NT_STATUS_INVALID_PARAMETER;
 346                 }
 347
 348                 if (spnego.negTokenInit.targetPrincipal) {
 349                         DEBUG(5, ("Server claims it's principal name is %s\n", spnego.negTokenInit.targetPrincipal));
 350                         nt_status = gensec_set_target_principal(gensec_security,
 351                                                                 spnego.negTokenInit.targetPrincipal);
 352                         if (!NT_STATUS_IS_OK(nt_status)) {
 353                                 return nt_status;
 354                         }
 355                 }
 356
 357                 mechType = spnego.negTokenInit.mechTypes;
 358                 for (i=0; mechType && mechType[i]; i++) {
 359                         nt_status = gensec_subcontext_start(gensec_security,
 360                                                             &spnego_state->sub_sec_security);
 361                         if (!NT_STATUS_IS_OK(nt_status)) {
 362                                 break;
 363                         }
 364                         /* select the sub context */
 365                         nt_status = gensec_start_mech_by_oid(spnego_state->sub_sec_security,
 366                                                              mechType[i]);
 367                         if (!NT_STATUS_IS_OK(nt_status)) {
 368                                 gensec_end(&spnego_state->sub_sec_security);
 369                                 continue;
 370                         }
 371
 372                         if (i == 0) {
 373                                 nt_status = gensec_update(spnego_state->sub_sec_security,
 374                                                           out_mem_ctx,
 375                                                           spnego.negTokenInit.mechToken,
 376                                                           &unwrapped_out);
 377                         } else {
 378                                 /* only get the helping start blob for the first OID */
 379                                 nt_status = gensec_update(spnego_state->sub_sec_security,
 380                                                           out_mem_ctx,
 381                                                           null_data_blob,
 382                                                           &unwrapped_out);
 383                         }
 384                         if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(nt_status)) {
 385                                 DEBUG(1, ("SPNEGO(%s) NEG_TOKEN_INIT failed: %s\n",
 386                                           spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 387                                 gensec_end(&spnego_state->sub_sec_security);
 388                         } else {
 389                                 break;
 390                         }
 391                 }
 392                 if (!mechType || !mechType[i]) {
 393                         DEBUG(1, ("SPNEGO: Could not find a suitable mechtype in NEG_TOKEN_INIT\n"));
 394                 }
 395
 396                 spnego_free_data(&spnego);
 397                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(nt_status)) {
 398                         return nt_status;
 399                 }
 400
 401                 /* compose reply */
 402                 my_mechs[0] = spnego_state->sub_sec_security->ops->oid;
 403
 404                 spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 405                 spnego_out.negTokenInit.mechTypes = my_mechs;
 406                 spnego_out.negTokenInit.reqFlags = 0;
 407                 spnego_out.negTokenInit.mechListMIC = null_data_blob;
 408                 spnego_out.negTokenInit.mechToken = unwrapped_out;
 409
 410                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 411                         DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_INIT\n"));
 412                                 return NT_STATUS_INVALID_PARAMETER;
 413                 }
 414
 415                 /* set next state */
 416                 spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 417                 spnego_state->state_position = SPNEGO_CLIENT_TARG;
 418
 419                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 420         }
 421         case SPNEGO_SERVER_TARG:
 422         {
 423                 NTSTATUS nt_status;
 424                 if (!in.length) {
 425                         return NT_STATUS_INVALID_PARAMETER;
 426                 }
 427
 428                 len = spnego_read_data(in, &spnego);
 429
 430                 if (len == -1) {
 431                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 432                         dump_data(1, (const char *)in.data, in.length);
 433                         return NT_STATUS_INVALID_PARAMETER;
 434                 }
 435
 436                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 437                 if (spnego.type != spnego_state->expected_packet) {
 438                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 439                                   spnego_state->expected_packet));
 440                         dump_data(1, (const char *)in.data, in.length);
 441                         spnego_free_data(&spnego);
 442                         return NT_STATUS_INVALID_PARAMETER;
 443                 }
 444
 445                 nt_status = gensec_update(spnego_state->sub_sec_security,
 446                                           out_mem_ctx,
 447                                           spnego.negTokenTarg.responseToken,
 448                                           &unwrapped_out);
 449
 450                 spnego_free_data(&spnego);
 451
 452                 /* compose reply */
 453                 spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
 454                 spnego_out.negTokenTarg.supportedMech
 455                         = spnego_state->sub_sec_security->ops->oid;
 456                 spnego_out.negTokenTarg.responseToken = unwrapped_out;
 457                 spnego_out.negTokenTarg.mechListMIC = null_data_blob;
 458
 459                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 460                         spnego_out.negTokenTarg.negResult = SPNEGO_ACCEPT_INCOMPLETE;
 461                         spnego_state->state_position = SPNEGO_SERVER_TARG;
 462                 } else if (NT_STATUS_IS_OK(nt_status)) {
 463                         spnego_out.negTokenTarg.negResult = SPNEGO_ACCEPT_COMPLETED;
 464                         spnego_state->state_position = SPNEGO_DONE;
 465                 } else {
 466                         spnego_out.negTokenTarg.negResult = SPNEGO_REJECT;
 467                         DEBUG(1, ("SPNEGO(%s) login failed: %s\n",
 468                                   spnego_state->sub_sec_security->ops->name,
 469                                   nt_errstr(nt_status)));
 470                         spnego_state->state_position = SPNEGO_DONE;
 471                 }
 472
 473                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 474                         DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
 475                         return NT_STATUS_INVALID_PARAMETER;
 476                 }
 477
 478                 return nt_status;
 479         }
 480         case SPNEGO_CLIENT_TARG:
 481         {
 482                 NTSTATUS nt_status;
 483                 if (!in.length) {
 484                         return NT_STATUS_INVALID_PARAMETER;
 485                 }
 486
 487                 len = spnego_read_data(in, &spnego);
 488
 489                 if (len == -1) {
 490                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 491                         dump_data(1, (const char *)in.data, in.length);
 492                         return NT_STATUS_INVALID_PARAMETER;
 493                 }
 494
 495                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 496                 if (spnego.type != spnego_state->expected_packet) {
 497                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 498                                   spnego_state->expected_packet));
 499                         dump_data(1, (const char *)in.data, in.length);
 500                         spnego_free_data(&spnego);
 501                         return NT_STATUS_INVALID_PARAMETER;
 502                 }
 503
 504                 if (spnego.negTokenTarg.negResult == SPNEGO_REJECT) {
 505                         return NT_STATUS_ACCESS_DENIED;
 506                 }
 507
 508                 nt_status = gensec_update(spnego_state->sub_sec_security,
 509                                           out_mem_ctx,
 510                                           spnego.negTokenTarg.responseToken,
 511                                           &unwrapped_out);
 512
 513
 514                 if (NT_STATUS_IS_OK(nt_status)
 515                     && (spnego.negTokenTarg.negResult != SPNEGO_ACCEPT_COMPLETED)) {
 516                         DEBUG(1,("gensec_update ok but not accepted\n"));
 517                         nt_status = NT_STATUS_INVALID_PARAMETER;
 518                 }
 519
 520                 spnego_free_data(&spnego);
 521
 522                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 523                         /* compose reply */
 524                         spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
 525                         spnego_out.negTokenTarg.negResult = SPNEGO_NONE_RESULT;
 526                         spnego_out.negTokenTarg.supportedMech = NULL;
 527                         spnego_out.negTokenTarg.responseToken = unwrapped_out;
 528                         spnego_out.negTokenTarg.mechListMIC = null_data_blob;
 529
 530                         if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 531                                 DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
 532                                 return NT_STATUS_INVALID_PARAMETER;
 533                         }
 534
 535                         spnego_state->state_position = SPNEGO_CLIENT_TARG;
 536                 } else if (NT_STATUS_IS_OK(nt_status)) {
 537                         /* all done - server has accepted, and we agree */
 538
 539                         if (unwrapped_out.length) {
 540                                 spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
 541                                 spnego_out.negTokenTarg.negResult = SPNEGO_NONE_RESULT;
 542                                 spnego_out.negTokenTarg.supportedMech = NULL;
 543                                 spnego_out.negTokenTarg.responseToken = unwrapped_out;
 544                                 spnego_out.negTokenTarg.mechListMIC = null_data_blob;
 545
 546                                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 547                                         DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
 548                                         return NT_STATUS_INVALID_PARAMETER;
 549                                 }
 550                         } else {
 551                                 *out = null_data_blob;
 552                         }
 553
 554                         spnego_state->state_position = SPNEGO_DONE;
 555                 } else {
 556                         DEBUG(1, ("SPNEGO(%s) login failed: %s\n",
 557                                   spnego_state->sub_sec_security->ops->name,
 558                                   nt_errstr(nt_status)));
 559                 }
 560                 return nt_status;
 561         }
 562         case SPNEGO_DONE:
 563                 return NT_STATUS_OK;
 564         }
 565         return NT_STATUS_INVALID_PARAMETER;
 566 }
 567
 568 static void gensec_spnego_end(struct gensec_security *gensec_security)
 569 {
 570         struct spnego_state *spnego_state = gensec_security->private_data;
 571
 572         if (spnego_state->sub_sec_security) {
 573                 gensec_end(&spnego_state->sub_sec_security);
 574         }
 575
 576         talloc_destroy(spnego_state->mem_ctx);
 577
 578         gensec_security->private_data = NULL;
 579 }
 580
 581 static const struct gensec_security_ops gensec_spnego_security_ops = {
 582         .name           = "spnego",
 583         .sasl_name      = "GSS-SPNEGO",
 584         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
 585         .oid            = OID_SPNEGO,
 586         .client_start   = gensec_spnego_client_start,
 587         .update         = gensec_spnego_update,
 588         .seal_packet    = gensec_spnego_seal_packet,
 589         .sign_packet    = gensec_spnego_sign_packet,
 590         .check_packet   = gensec_spnego_check_packet,
 591         .unseal_packet  = gensec_spnego_unseal_packet,
 592         .session_key    = gensec_spnego_session_key,
 593         .end            = gensec_spnego_end
 594 };
 595
 596 NTSTATUS gensec_spnego_init(void)
 597 {
 598         NTSTATUS ret;
 599         ret = register_backend("gensec", &gensec_spnego_security_ops);
 600         if (!NT_STATUS_IS_OK(ret)) {
 601                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
 602                         gensec_spnego_security_ops.name));
 603                 return ret;
 604         }
 605
 606         return ret;
 607 }