auth/gensec/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> 2004-2005
   8    Copyright (C) Stefan Metzmacher <metze@samba.org>  2004-2008
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 3 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20
  21    You should have received a copy of the GNU General Public License
  22    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23 */
  24
  25 #include "includes.h"
  26 #include "../libcli/auth/spnego.h"
  27 #include "librpc/gen_ndr/ndr_dcerpc.h"
  28 #include "auth/credentials/credentials.h"
  29 #include "auth/gensec/gensec.h"
  30 #include "auth/gensec/gensec_internal.h"
  31 #include "param/param.h"
  32 #include "lib/util/asn1.h"
  33
  34 #undef strcasecmp
  35
  36 _PUBLIC_ NTSTATUS gensec_spnego_init(void);
  37
  38 enum spnego_state_position {
  39         SPNEGO_SERVER_START,
  40         SPNEGO_CLIENT_START,
  41         SPNEGO_SERVER_TARG,
  42         SPNEGO_CLIENT_TARG,
  43         SPNEGO_FALLBACK,
  44         SPNEGO_DONE
  45 };
  46
  47 struct spnego_state {
  48         enum spnego_message_type expected_packet;
  49         enum spnego_state_position state_position;
  50         struct gensec_security *sub_sec_security;
  51         bool no_response_expected;
  52
  53         const char *neg_oid;
  54
  55         DATA_BLOB mech_types;
  56
  57         /*
  58          * The following is used to implement
  59          * the update token fragmentation
  60          */
  61         size_t in_needed;
  62         DATA_BLOB in_frag;
  63         size_t out_max_length;
  64         DATA_BLOB out_frag;
  65         NTSTATUS out_status;
  66 };
  67
  68
  69 static NTSTATUS gensec_spnego_client_start(struct gensec_security *gensec_security)
  70 {
  71         struct spnego_state *spnego_state;
  72
  73         spnego_state = talloc_zero(gensec_security, struct spnego_state);
  74         if (!spnego_state) {
  75                 return NT_STATUS_NO_MEMORY;
  76         }
  77
  78         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_INIT;
  79         spnego_state->state_position = SPNEGO_CLIENT_START;
  80         spnego_state->sub_sec_security = NULL;
  81         spnego_state->no_response_expected = false;
  82         spnego_state->mech_types = data_blob(NULL, 0);
  83         spnego_state->out_max_length = gensec_max_update_size(gensec_security);
  84         spnego_state->out_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
  85
  86         gensec_security->private_data = spnego_state;
  87         return NT_STATUS_OK;
  88 }
  89
  90 static NTSTATUS gensec_spnego_server_start(struct gensec_security *gensec_security)
  91 {
  92         struct spnego_state *spnego_state;
  93
  94         spnego_state = talloc_zero(gensec_security, struct spnego_state);
  95         if (!spnego_state) {
  96                 return NT_STATUS_NO_MEMORY;
  97         }
  98
  99         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_INIT;
 100         spnego_state->state_position = SPNEGO_SERVER_START;
 101         spnego_state->sub_sec_security = NULL;
 102         spnego_state->no_response_expected = false;
 103         spnego_state->mech_types = data_blob(NULL, 0);
 104         spnego_state->out_max_length = gensec_max_update_size(gensec_security);
 105         spnego_state->out_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 106
 107         gensec_security->private_data = spnego_state;
 108         return NT_STATUS_OK;
 109 }
 110
 111 /*
 112   wrappers for the spnego_*() functions
 113 */
 114 static NTSTATUS gensec_spnego_unseal_packet(struct gensec_security *gensec_security,
 115                                             uint8_t *data, size_t length,
 116                                             const uint8_t *whole_pdu, size_t pdu_length,
 117                                             const DATA_BLOB *sig)
 118 {
 119         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 120
 121         if (spnego_state->state_position != SPNEGO_DONE
 122             && spnego_state->state_position != SPNEGO_FALLBACK) {
 123                 return NT_STATUS_INVALID_PARAMETER;
 124         }
 125
 126         return gensec_unseal_packet(spnego_state->sub_sec_security,
 127                                     data, length,
 128                                     whole_pdu, pdu_length,
 129                                     sig);
 130 }
 131
 132 static NTSTATUS gensec_spnego_check_packet(struct gensec_security *gensec_security,
 133                                            const uint8_t *data, size_t length,
 134                                            const uint8_t *whole_pdu, size_t pdu_length,
 135                                            const DATA_BLOB *sig)
 136 {
 137         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 138
 139         if (spnego_state->state_position != SPNEGO_DONE
 140             && spnego_state->state_position != SPNEGO_FALLBACK) {
 141                 return NT_STATUS_INVALID_PARAMETER;
 142         }
 143
 144         return gensec_check_packet(spnego_state->sub_sec_security,
 145                                    data, length,
 146                                    whole_pdu, pdu_length,
 147                                    sig);
 148 }
 149
 150 static NTSTATUS gensec_spnego_seal_packet(struct gensec_security *gensec_security,
 151                                           TALLOC_CTX *mem_ctx,
 152                                           uint8_t *data, size_t length,
 153                                           const uint8_t *whole_pdu, size_t pdu_length,
 154                                           DATA_BLOB *sig)
 155 {
 156         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 157
 158         if (spnego_state->state_position != SPNEGO_DONE
 159             && spnego_state->state_position != SPNEGO_FALLBACK) {
 160                 return NT_STATUS_INVALID_PARAMETER;
 161         }
 162
 163         return gensec_seal_packet(spnego_state->sub_sec_security,
 164                                   mem_ctx,
 165                                   data, length,
 166                                   whole_pdu, pdu_length,
 167                                   sig);
 168 }
 169
 170 static NTSTATUS gensec_spnego_sign_packet(struct gensec_security *gensec_security,
 171                                           TALLOC_CTX *mem_ctx,
 172                                           const uint8_t *data, size_t length,
 173                                           const uint8_t *whole_pdu, size_t pdu_length,
 174                                           DATA_BLOB *sig)
 175 {
 176         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 177
 178         if (spnego_state->state_position != SPNEGO_DONE
 179             && spnego_state->state_position != SPNEGO_FALLBACK) {
 180                 return NT_STATUS_INVALID_PARAMETER;
 181         }
 182
 183         return gensec_sign_packet(spnego_state->sub_sec_security,
 184                                   mem_ctx,
 185                                   data, length,
 186                                   whole_pdu, pdu_length,
 187                                   sig);
 188 }
 189
 190 static NTSTATUS gensec_spnego_wrap(struct gensec_security *gensec_security,
 191                                    TALLOC_CTX *mem_ctx,
 192                                    const DATA_BLOB *in,
 193                                    DATA_BLOB *out)
 194 {
 195         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 196
 197         if (spnego_state->state_position != SPNEGO_DONE
 198             && spnego_state->state_position != SPNEGO_FALLBACK) {
 199                 DEBUG(1, ("gensec_spnego_wrap: wrong state for wrap\n"));
 200                 return NT_STATUS_INVALID_PARAMETER;
 201         }
 202
 203         return gensec_wrap(spnego_state->sub_sec_security,
 204                            mem_ctx, in, out);
 205 }
 206
 207 static NTSTATUS gensec_spnego_unwrap(struct gensec_security *gensec_security,
 208                                      TALLOC_CTX *mem_ctx,
 209                                      const DATA_BLOB *in,
 210                                      DATA_BLOB *out)
 211 {
 212         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 213
 214         if (spnego_state->state_position != SPNEGO_DONE
 215             && spnego_state->state_position != SPNEGO_FALLBACK) {
 216                 DEBUG(1, ("gensec_spnego_unwrap: wrong state for unwrap\n"));
 217                 return NT_STATUS_INVALID_PARAMETER;
 218         }
 219
 220         return gensec_unwrap(spnego_state->sub_sec_security,
 221                              mem_ctx, in, out);
 222 }
 223
 224 static NTSTATUS gensec_spnego_wrap_packets(struct gensec_security *gensec_security,
 225                                            TALLOC_CTX *mem_ctx,
 226                                            const DATA_BLOB *in,
 227                                            DATA_BLOB *out,
 228                                            size_t *len_processed)
 229 {
 230         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 231
 232         if (spnego_state->state_position != SPNEGO_DONE
 233             && spnego_state->state_position != SPNEGO_FALLBACK) {
 234                 DEBUG(1, ("gensec_spnego_wrap: wrong state for wrap\n"));
 235                 return NT_STATUS_INVALID_PARAMETER;
 236         }
 237
 238         return gensec_wrap_packets(spnego_state->sub_sec_security,
 239                                    mem_ctx, in, out,
 240                                    len_processed);
 241 }
 242
 243 static NTSTATUS gensec_spnego_packet_full_request(struct gensec_security *gensec_security,
 244                                                 DATA_BLOB blob, size_t *size)
 245 {
 246         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 247
 248         if (spnego_state->state_position != SPNEGO_DONE
 249             && spnego_state->state_position != SPNEGO_FALLBACK) {
 250                 DEBUG(1, ("gensec_spnego_unwrap: wrong state for unwrap\n"));
 251                 return NT_STATUS_INVALID_PARAMETER;
 252         }
 253
 254         return gensec_packet_full_request(spnego_state->sub_sec_security,
 255                                           blob, size);
 256 }
 257
 258 static NTSTATUS gensec_spnego_unwrap_packets(struct gensec_security *gensec_security,
 259                                              TALLOC_CTX *mem_ctx,
 260                                              const DATA_BLOB *in,
 261                                              DATA_BLOB *out,
 262                                              size_t *len_processed)
 263 {
 264         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 265
 266         if (spnego_state->state_position != SPNEGO_DONE
 267             && spnego_state->state_position != SPNEGO_FALLBACK) {
 268                 DEBUG(1, ("gensec_spnego_unwrap: wrong state for unwrap\n"));
 269                 return NT_STATUS_INVALID_PARAMETER;
 270         }
 271
 272         return gensec_unwrap_packets(spnego_state->sub_sec_security,
 273                                      mem_ctx, in, out,
 274                                      len_processed);
 275 }
 276
 277 static size_t gensec_spnego_sig_size(struct gensec_security *gensec_security, size_t data_size)
 278 {
 279         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 280
 281         if (spnego_state->state_position != SPNEGO_DONE
 282             && spnego_state->state_position != SPNEGO_FALLBACK) {
 283                 return 0;
 284         }
 285
 286         return gensec_sig_size(spnego_state->sub_sec_security, data_size);
 287 }
 288
 289 static size_t gensec_spnego_max_input_size(struct gensec_security *gensec_security)
 290 {
 291         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 292
 293         if (spnego_state->state_position != SPNEGO_DONE
 294             && spnego_state->state_position != SPNEGO_FALLBACK) {
 295                 return 0;
 296         }
 297
 298         return gensec_max_input_size(spnego_state->sub_sec_security);
 299 }
 300
 301 static size_t gensec_spnego_max_wrapped_size(struct gensec_security *gensec_security)
 302 {
 303         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 304
 305         if (spnego_state->state_position != SPNEGO_DONE
 306             && spnego_state->state_position != SPNEGO_FALLBACK) {
 307                 return 0;
 308         }
 309
 310         return gensec_max_wrapped_size(spnego_state->sub_sec_security);
 311 }
 312
 313 static NTSTATUS gensec_spnego_session_key(struct gensec_security *gensec_security,
 314                                           TALLOC_CTX *mem_ctx,
 315                                           DATA_BLOB *session_key)
 316 {
 317         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 318         if (!spnego_state->sub_sec_security) {
 319                 return NT_STATUS_INVALID_PARAMETER;
 320         }
 321
 322         return gensec_session_key(spnego_state->sub_sec_security,
 323                                   mem_ctx,
 324                                   session_key);
 325 }
 326
 327 static NTSTATUS gensec_spnego_session_info(struct gensec_security *gensec_security,
 328                                            TALLOC_CTX *mem_ctx,
 329                                            struct auth_session_info **session_info)
 330 {
 331         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 332         if (!spnego_state->sub_sec_security) {
 333                 return NT_STATUS_INVALID_PARAMETER;
 334         }
 335
 336         return gensec_session_info(spnego_state->sub_sec_security,
 337                                    mem_ctx,
 338                                    session_info);
 339 }
 340
 341 /** Fallback to another GENSEC mechanism, based on magic strings
 342  *
 343  * This is the 'fallback' case, where we don't get SPNEGO, and have to
 344  * try all the other options (and hope they all have a magic string
 345  * they check)
 346 */
 347
 348 static NTSTATUS gensec_spnego_server_try_fallback(struct gensec_security *gensec_security,
 349                                                   struct spnego_state *spnego_state,
 350                                                   struct tevent_context *ev,
 351                                                   TALLOC_CTX *out_mem_ctx,
 352                                                   const DATA_BLOB in, DATA_BLOB *out)
 353 {
 354         int i,j;
 355         struct gensec_security_ops **all_ops
 356                 = gensec_security_mechs(gensec_security, out_mem_ctx);
 357         for (i=0; all_ops[i]; i++) {
 358                 bool is_spnego;
 359                 NTSTATUS nt_status;
 360
 361                 if (gensec_security != NULL &&
 362                                 !gensec_security_ops_enabled(all_ops[i], gensec_security))
 363                     continue;
 364
 365                 if (!all_ops[i]->oid) {
 366                         continue;
 367                 }
 368
 369                 is_spnego = false;
 370                 for (j=0; all_ops[i]->oid[j]; j++) {
 371                         if (strcasecmp(GENSEC_OID_SPNEGO,all_ops[i]->oid[j]) == 0) {
 372                                 is_spnego = true;
 373                         }
 374                 }
 375                 if (is_spnego) {
 376                         continue;
 377                 }
 378
 379                 if (!all_ops[i]->magic) {
 380                         continue;
 381                 }
 382
 383                 nt_status = all_ops[i]->magic(gensec_security, &in);
 384                 if (!NT_STATUS_IS_OK(nt_status)) {
 385                         continue;
 386                 }
 387
 388                 spnego_state->state_position = SPNEGO_FALLBACK;
 389
 390                 nt_status = gensec_subcontext_start(spnego_state,
 391                                                     gensec_security,
 392                                                     &spnego_state->sub_sec_security);
 393
 394                 if (!NT_STATUS_IS_OK(nt_status)) {
 395                         return nt_status;
 396                 }
 397                 /* select the sub context */
 398                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 399                                                      all_ops[i]);
 400                 if (!NT_STATUS_IS_OK(nt_status)) {
 401                         return nt_status;
 402                 }
 403                 nt_status = gensec_update(spnego_state->sub_sec_security,
 404                                           ev, out_mem_ctx, in, out);
 405                 return nt_status;
 406         }
 407         DEBUG(1, ("Failed to parse SPNEGO request\n"));
 408         return NT_STATUS_INVALID_PARAMETER;
 409 }
 410
 411 /*
 412    Parse the netTokenInit, either from the client, to the server, or
 413    from the server to the client.
 414 */
 415
 416 static NTSTATUS gensec_spnego_parse_negTokenInit(struct gensec_security *gensec_security,
 417                                                  struct spnego_state *spnego_state,
 418                                                  TALLOC_CTX *out_mem_ctx,
 419                                                  struct tevent_context *ev,
 420                                                  const char **mechType,
 421                                                  const DATA_BLOB unwrapped_in, DATA_BLOB *unwrapped_out)
 422 {
 423         int i;
 424         NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 425         DATA_BLOB null_data_blob = data_blob(NULL,0);
 426         bool ok;
 427
 428         const struct gensec_security_ops_wrapper *all_sec
 429                 = gensec_security_by_oid_list(gensec_security,
 430                                               out_mem_ctx,
 431                                               mechType,
 432                                               GENSEC_OID_SPNEGO);
 433
 434         ok = spnego_write_mech_types(spnego_state,
 435                                      mechType,
 436                                      &spnego_state->mech_types);
 437         if (!ok) {
 438                 DEBUG(1, ("SPNEGO: Failed to write mechTypes\n"));
 439                 return NT_STATUS_NO_MEMORY;
 440         }
 441
 442         if (spnego_state->state_position == SPNEGO_SERVER_START) {
 443                 uint32_t j;
 444                 for (j=0; mechType && mechType[j]; j++) {
 445                         for (i=0; all_sec && all_sec[i].op; i++) {
 446                                 if (strcmp(mechType[j], all_sec[i].oid) != 0) {
 447                                         continue;
 448                                 }
 449
 450                                 nt_status = gensec_subcontext_start(spnego_state,
 451                                                                     gensec_security,
 452                                                                     &spnego_state->sub_sec_security);
 453                                 if (!NT_STATUS_IS_OK(nt_status)) {
 454                                         return nt_status;
 455                                 }
 456                                 /* select the sub context */
 457                                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 458                                                                      all_sec[i].op);
 459                                 if (!NT_STATUS_IS_OK(nt_status)) {
 460                                         talloc_free(spnego_state->sub_sec_security);
 461                                         spnego_state->sub_sec_security = NULL;
 462                                         break;
 463                                 }
 464
 465                                 if (j > 0) {
 466                                         /* no optimistic token */
 467                                         spnego_state->neg_oid = all_sec[i].oid;
 468                                         *unwrapped_out = data_blob_null;
 469                                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 470                                         break;
 471                                 }
 472
 473                                 nt_status = gensec_update(spnego_state->sub_sec_security,
 474                                                           out_mem_ctx,
 475                                                           ev,
 476                                                           unwrapped_in,
 477                                                           unwrapped_out);
 478                                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER) ||
 479                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_CANT_ACCESS_DOMAIN_INFO)) {
 480                                         /* Pretend we never started it (lets the first run find some incompatible demand) */
 481
 482                                         DEBUG(1, ("SPNEGO(%s) NEG_TOKEN_INIT failed to parse contents: %s\n",
 483                                                   spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 484                                         talloc_free(spnego_state->sub_sec_security);
 485                                         spnego_state->sub_sec_security = NULL;
 486                                         break;
 487                                 }
 488
 489                                 spnego_state->neg_oid = all_sec[i].oid;
 490                                 break;
 491                         }
 492                         if (spnego_state->sub_sec_security) {
 493                                 break;
 494                         }
 495                 }
 496
 497                 if (!spnego_state->sub_sec_security) {
 498                         DEBUG(1, ("SPNEGO: Could not find a suitable mechtype in NEG_TOKEN_INIT\n"));
 499                         return NT_STATUS_INVALID_PARAMETER;
 500                 }
 501         }
 502
 503         /* Having tried any optimistic token from the client (if we
 504          * were the server), if we didn't get anywhere, walk our list
 505          * in our preference order */
 506
 507         if (!spnego_state->sub_sec_security) {
 508                 for (i=0; all_sec && all_sec[i].op; i++) {
 509                         nt_status = gensec_subcontext_start(spnego_state,
 510                                                             gensec_security,
 511                                                             &spnego_state->sub_sec_security);
 512                         if (!NT_STATUS_IS_OK(nt_status)) {
 513                                 return nt_status;
 514                         }
 515                         /* select the sub context */
 516                         nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 517                                                              all_sec[i].op);
 518                         if (!NT_STATUS_IS_OK(nt_status)) {
 519                                 talloc_free(spnego_state->sub_sec_security);
 520                                 spnego_state->sub_sec_security = NULL;
 521                                 continue;
 522                         }
 523
 524                         spnego_state->neg_oid = all_sec[i].oid;
 525
 526                         /* only get the helping start blob for the first OID */
 527                         nt_status = gensec_update(spnego_state->sub_sec_security,
 528                                                   out_mem_ctx,
 529                                                   ev,
 530                                                   null_data_blob,
 531                                                   unwrapped_out);
 532
 533                         /* it is likely that a NULL input token will
 534                          * not be liked by most server mechs, but if
 535                          * we are in the client, we want the first
 536                          * update packet to be able to abort the use
 537                          * of this mech */
 538                         if (spnego_state->state_position != SPNEGO_SERVER_START) {
 539                                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER) ||
 540                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_LOGON_SERVERS) ||
 541                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_TIME_DIFFERENCE_AT_DC) ||
 542                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_CANT_ACCESS_DOMAIN_INFO)) {
 543                                         /* Pretend we never started it (lets the first run find some incompatible demand) */
 544
 545                                         DEBUG(3, ("SPNEGO(%s) NEG_TOKEN_INIT failed: %s\n",
 546                                                   spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 547                                         talloc_free(spnego_state->sub_sec_security);
 548                                         spnego_state->sub_sec_security = NULL;
 549                                         continue;
 550                                 }
 551                         }
 552
 553                         break;
 554                 }
 555         }
 556
 557         if (spnego_state->sub_sec_security) {
 558                 /* it is likely that a NULL input token will
 559                  * not be liked by most server mechs, but this
 560                  * does the right thing in the CIFS client.
 561                  * just push us along the merry-go-round
 562                  * again, and hope for better luck next
 563                  * time */
 564
 565                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER)) {
 566                         *unwrapped_out = data_blob(NULL, 0);
 567                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 568                 }
 569
 570                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER)
 571                     && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
 572                     && !NT_STATUS_IS_OK(nt_status)) {
 573                         DEBUG(1, ("SPNEGO(%s) NEG_TOKEN_INIT failed: %s\n",
 574                                   spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 575                         talloc_free(spnego_state->sub_sec_security);
 576                         spnego_state->sub_sec_security = NULL;
 577
 578                         /* We started the mech correctly, and the
 579                          * input from the other side was valid.
 580                          * Return the error (say bad password, invalid
 581                          * ticket) */
 582                         return nt_status;
 583                 }
 584
 585                 return nt_status; /* OK, INVALID_PARAMETER ore MORE PROCESSING */
 586         }
 587
 588         DEBUG(1, ("SPNEGO: Could not find a suitable mechtype in NEG_TOKEN_INIT\n"));
 589         /* we could re-negotiate here, but it would only work
 590          * if the client or server lied about what it could
 591          * support the first time.  Lets keep this code to
 592          * reality */
 593
 594         return nt_status;
 595 }
 596
 597 /** create a negTokenInit
 598  *
 599  * This is the same packet, no matter if the client or server sends it first, but it is always the first packet
 600 */
 601 static NTSTATUS gensec_spnego_create_negTokenInit(struct gensec_security *gensec_security,
 602                                                   struct spnego_state *spnego_state,
 603                                                   TALLOC_CTX *out_mem_ctx,
 604                                                   struct tevent_context *ev,
 605                                                   const DATA_BLOB in, DATA_BLOB *out)
 606 {
 607         int i;
 608         NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 609         DATA_BLOB null_data_blob = data_blob(NULL,0);
 610         const char **mechTypes = NULL;
 611         DATA_BLOB unwrapped_out = data_blob(NULL, 0);
 612         const struct gensec_security_ops_wrapper *all_sec;
 613
 614         mechTypes = gensec_security_oids(gensec_security,
 615                                          out_mem_ctx, GENSEC_OID_SPNEGO);
 616
 617         all_sec = gensec_security_by_oid_list(gensec_security,
 618                                               out_mem_ctx,
 619                                               mechTypes,
 620                                               GENSEC_OID_SPNEGO);
 621         for (i=0; all_sec && all_sec[i].op; i++) {
 622                 struct spnego_data spnego_out;
 623                 const char **send_mech_types;
 624                 bool ok;
 625
 626                 nt_status = gensec_subcontext_start(spnego_state,
 627                                                     gensec_security,
 628                                                     &spnego_state->sub_sec_security);
 629                 if (!NT_STATUS_IS_OK(nt_status)) {
 630                         return nt_status;
 631                 }
 632                 /* select the sub context */
 633                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 634                                                      all_sec[i].op);
 635                 if (!NT_STATUS_IS_OK(nt_status)) {
 636                         talloc_free(spnego_state->sub_sec_security);
 637                         spnego_state->sub_sec_security = NULL;
 638                         continue;
 639                 }
 640
 641                 /* In the client, try and produce the first (optimistic) packet */
 642                 if (spnego_state->state_position == SPNEGO_CLIENT_START) {
 643                         nt_status = gensec_update(spnego_state->sub_sec_security,
 644                                                   out_mem_ctx,
 645                                                   ev,
 646                                                   null_data_blob,
 647                                                   &unwrapped_out);
 648
 649                         if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
 650                             && !NT_STATUS_IS_OK(nt_status)) {
 651                                 DEBUG(1, ("SPNEGO(%s) creating NEG_TOKEN_INIT failed: %s\n",
 652                                           spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 653                                 talloc_free(spnego_state->sub_sec_security);
 654                                 spnego_state->sub_sec_security = NULL;
 655                                 /* Pretend we never started it (lets the first run find some incompatible demand) */
 656
 657                                 continue;
 658                         }
 659                 }
 660
 661                 spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 662
 663                 send_mech_types = gensec_security_oids_from_ops_wrapped(out_mem_ctx,
 664                                                                         &all_sec[i]);
 665
 666                 ok = spnego_write_mech_types(spnego_state,
 667                                              send_mech_types,
 668                                              &spnego_state->mech_types);
 669                 if (!ok) {
 670                         DEBUG(1, ("SPNEGO: Failed to write mechTypes\n"));
 671                         return NT_STATUS_NO_MEMORY;
 672                 }
 673
 674                 /* List the remaining mechs as options */
 675                 spnego_out.negTokenInit.mechTypes = send_mech_types;
 676                 spnego_out.negTokenInit.reqFlags = null_data_blob;
 677                 spnego_out.negTokenInit.reqFlagsPadding = 0;
 678
 679                 if (spnego_state->state_position == SPNEGO_SERVER_START) {
 680                         spnego_out.negTokenInit.mechListMIC
 681                                 = data_blob_string_const(ADS_IGNORE_PRINCIPAL);
 682                 } else {
 683                         spnego_out.negTokenInit.mechListMIC = null_data_blob;
 684                 }
 685
 686                 spnego_out.negTokenInit.mechToken = unwrapped_out;
 687
 688                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 689                         DEBUG(1, ("Failed to write NEG_TOKEN_INIT\n"));
 690                                 return NT_STATUS_INVALID_PARAMETER;
 691                 }
 692
 693                 /* set next state */
 694                 spnego_state->neg_oid = all_sec[i].oid;
 695
 696                 if (NT_STATUS_IS_OK(nt_status)) {
 697                         spnego_state->no_response_expected = true;
 698                 }
 699
 700                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 701         }
 702         talloc_free(spnego_state->sub_sec_security);
 703         spnego_state->sub_sec_security = NULL;
 704
 705         DEBUG(1, ("Failed to setup SPNEGO negTokenInit request: %s\n", nt_errstr(nt_status)));
 706         return NT_STATUS_INVALID_PARAMETER;
 707 }
 708
 709
 710 /** create a server negTokenTarg
 711  *
 712  * This is the case, where the client is the first one who sends data
 713 */
 714
 715 static NTSTATUS gensec_spnego_server_negTokenTarg(struct spnego_state *spnego_state,
 716                                                   TALLOC_CTX *out_mem_ctx,
 717                                                   NTSTATUS nt_status,
 718                                                   const DATA_BLOB unwrapped_out,
 719                                                   DATA_BLOB mech_list_mic,
 720                                                   DATA_BLOB *out)
 721 {
 722         struct spnego_data spnego_out;
 723         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 724
 725         /* compose reply */
 726         spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
 727         spnego_out.negTokenTarg.responseToken = unwrapped_out;
 728         spnego_out.negTokenTarg.mechListMIC = null_data_blob;
 729         spnego_out.negTokenTarg.supportedMech = NULL;
 730
 731         if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 732                 spnego_out.negTokenTarg.supportedMech = spnego_state->neg_oid;
 733                 spnego_out.negTokenTarg.negResult = SPNEGO_ACCEPT_INCOMPLETE;
 734                 spnego_state->state_position = SPNEGO_SERVER_TARG;
 735         } else if (NT_STATUS_IS_OK(nt_status)) {
 736                 if (unwrapped_out.data) {
 737                         spnego_out.negTokenTarg.supportedMech = spnego_state->neg_oid;
 738                 }
 739                 spnego_out.negTokenTarg.negResult = SPNEGO_ACCEPT_COMPLETED;
 740                 spnego_out.negTokenTarg.mechListMIC = mech_list_mic;
 741                 spnego_state->state_position = SPNEGO_DONE;
 742         } else {
 743                 spnego_out.negTokenTarg.negResult = SPNEGO_REJECT;
 744                 DEBUG(2, ("SPNEGO login failed: %s\n", nt_errstr(nt_status)));
 745                 spnego_state->state_position = SPNEGO_DONE;
 746         }
 747
 748         if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 749                 DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
 750                 return NT_STATUS_INVALID_PARAMETER;
 751         }
 752
 753         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 754
 755         return nt_status;
 756 }
 757
 758
 759 static NTSTATUS gensec_spnego_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx,
 760                                      struct tevent_context *ev,
 761                                      const DATA_BLOB in, DATA_BLOB *out)
 762 {
 763         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 764         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 765         DATA_BLOB mech_list_mic = data_blob(NULL, 0);
 766         DATA_BLOB unwrapped_out = data_blob(NULL, 0);
 767         struct spnego_data spnego_out;
 768         struct spnego_data spnego;
 769
 770         ssize_t len;
 771
 772         *out = data_blob(NULL, 0);
 773
 774         if (!out_mem_ctx) {
 775                 out_mem_ctx = spnego_state;
 776         }
 777
 778         /* and switch into the state machine */
 779
 780         switch (spnego_state->state_position) {
 781         case SPNEGO_FALLBACK:
 782                 return gensec_update(spnego_state->sub_sec_security, ev,
 783                                      out_mem_ctx, in, out);
 784         case SPNEGO_SERVER_START:
 785         {
 786                 NTSTATUS nt_status;
 787                 if (in.length) {
 788
 789                         len = spnego_read_data(gensec_security, in, &spnego);
 790                         if (len == -1) {
 791                                 return gensec_spnego_server_try_fallback(gensec_security, spnego_state,
 792                                                                          out_mem_ctx, ev, in, out);
 793                         }
 794                         /* client sent NegTargetInit, we send NegTokenTarg */
 795
 796                         /* OK, so it's real SPNEGO, check the packet's the one we expect */
 797                         if (spnego.type != spnego_state->expected_packet) {
 798                                 DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 799                                           spnego_state->expected_packet));
 800                                 dump_data(1, in.data, in.length);
 801                                 spnego_free_data(&spnego);
 802                                 return NT_STATUS_INVALID_PARAMETER;
 803                         }
 804
 805                         nt_status = gensec_spnego_parse_negTokenInit(gensec_security,
 806                                                                      spnego_state,
 807                                                                      out_mem_ctx,
 808                                                                      ev,
 809                                                                      spnego.negTokenInit.mechTypes,
 810                                                                      spnego.negTokenInit.mechToken,
 811                                                                      &unwrapped_out);
 812
 813                         nt_status = gensec_spnego_server_negTokenTarg(spnego_state,
 814                                                                       out_mem_ctx,
 815                                                                       nt_status,
 816                                                                       unwrapped_out,
 817                                                                       null_data_blob,
 818                                                                       out);
 819
 820                         spnego_free_data(&spnego);
 821
 822                         return nt_status;
 823                 } else {
 824                         nt_status = gensec_spnego_create_negTokenInit(gensec_security, spnego_state,
 825                                                                       out_mem_ctx, ev, in, out);
 826                         spnego_state->state_position = SPNEGO_SERVER_START;
 827                         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_INIT;
 828                         return nt_status;
 829                 }
 830         }
 831
 832         case SPNEGO_CLIENT_START:
 833         {
 834                 /* The server offers a list of mechanisms */
 835
 836                 const char *my_mechs[] = {NULL, NULL};
 837                 NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 838
 839                 if (!in.length) {
 840                         /* client to produce negTokenInit */
 841                         nt_status = gensec_spnego_create_negTokenInit(gensec_security, spnego_state,
 842                                                                       out_mem_ctx, ev, in, out);
 843                         spnego_state->state_position = SPNEGO_CLIENT_TARG;
 844                         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 845                         return nt_status;
 846                 }
 847
 848                 len = spnego_read_data(gensec_security, in, &spnego);
 849
 850                 if (len == -1) {
 851                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 852                         dump_data(1, in.data, in.length);
 853                         return NT_STATUS_INVALID_PARAMETER;
 854                 }
 855
 856                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 857                 if (spnego.type != spnego_state->expected_packet) {
 858                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 859                                   spnego_state->expected_packet));
 860                         dump_data(1, in.data, in.length);
 861                         spnego_free_data(&spnego);
 862                         return NT_STATUS_INVALID_PARAMETER;
 863                 }
 864
 865                 if (spnego.negTokenInit.targetPrincipal
 866                     && strcmp(spnego.negTokenInit.targetPrincipal, ADS_IGNORE_PRINCIPAL) != 0) {
 867                         DEBUG(5, ("Server claims it's principal name is %s\n", spnego.negTokenInit.targetPrincipal));
 868                         if (lpcfg_client_use_spnego_principal(gensec_security->settings->lp_ctx)) {
 869                                 gensec_set_target_principal(gensec_security, spnego.negTokenInit.targetPrincipal);
 870                         }
 871                 }
 872
 873                 nt_status = gensec_spnego_parse_negTokenInit(gensec_security,
 874                                                              spnego_state,
 875                                                              out_mem_ctx,
 876                                                              ev,
 877                                                              spnego.negTokenInit.mechTypes,
 878                                                              spnego.negTokenInit.mechToken,
 879                                                              &unwrapped_out);
 880
 881                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(nt_status)) {
 882                         spnego_free_data(&spnego);
 883                         return nt_status;
 884                 }
 885
 886                 my_mechs[0] = spnego_state->neg_oid;
 887                 /* compose reply */
 888                 spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 889                 spnego_out.negTokenInit.mechTypes = my_mechs;
 890                 spnego_out.negTokenInit.reqFlags = null_data_blob;
 891                 spnego_out.negTokenInit.reqFlagsPadding = 0;
 892                 spnego_out.negTokenInit.mechListMIC = null_data_blob;
 893                 spnego_out.negTokenInit.mechToken = unwrapped_out;
 894
 895                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 896                         DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_INIT\n"));
 897                                 return NT_STATUS_INVALID_PARAMETER;
 898                 }
 899
 900                 /* set next state */
 901                 spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 902                 spnego_state->state_position = SPNEGO_CLIENT_TARG;
 903
 904                 if (NT_STATUS_IS_OK(nt_status)) {
 905                         spnego_state->no_response_expected = true;
 906                 }
 907
 908                 spnego_free_data(&spnego);
 909                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 910         }
 911         case SPNEGO_SERVER_TARG:
 912         {
 913                 NTSTATUS nt_status;
 914                 bool new_spnego = false;
 915
 916                 if (!in.length) {
 917                         return NT_STATUS_INVALID_PARAMETER;
 918                 }
 919
 920                 len = spnego_read_data(gensec_security, in, &spnego);
 921
 922                 if (len == -1) {
 923                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 924                         dump_data(1, in.data, in.length);
 925                         return NT_STATUS_INVALID_PARAMETER;
 926                 }
 927
 928                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 929                 if (spnego.type != spnego_state->expected_packet) {
 930                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 931                                   spnego_state->expected_packet));
 932                         dump_data(1, in.data, in.length);
 933                         spnego_free_data(&spnego);
 934                         return NT_STATUS_INVALID_PARAMETER;
 935                 }
 936
 937                 if (!spnego_state->sub_sec_security) {
 938                         DEBUG(1, ("SPNEGO: Did not setup a mech in NEG_TOKEN_INIT\n"));
 939                         spnego_free_data(&spnego);
 940                         return NT_STATUS_INVALID_PARAMETER;
 941                 }
 942
 943                 nt_status = gensec_update(spnego_state->sub_sec_security,
 944                                           out_mem_ctx, ev,
 945                                           spnego.negTokenTarg.responseToken,
 946                                           &unwrapped_out);
 947                 if (NT_STATUS_IS_OK(nt_status) && spnego.negTokenTarg.mechListMIC.length > 0) {
 948                         new_spnego = true;
 949                         nt_status = gensec_check_packet(spnego_state->sub_sec_security,
 950                                                         spnego_state->mech_types.data,
 951                                                         spnego_state->mech_types.length,
 952                                                         spnego_state->mech_types.data,
 953                                                         spnego_state->mech_types.length,
 954                                                         &spnego.negTokenTarg.mechListMIC);
 955                         if (!NT_STATUS_IS_OK(nt_status)) {
 956                                 DEBUG(2,("GENSEC SPNEGO: failed to verify mechListMIC: %s\n",
 957                                         nt_errstr(nt_status)));
 958                         }
 959                 }
 960                 if (NT_STATUS_IS_OK(nt_status) && new_spnego) {
 961                         nt_status = gensec_sign_packet(spnego_state->sub_sec_security,
 962                                                        out_mem_ctx,
 963                                                        spnego_state->mech_types.data,
 964                                                        spnego_state->mech_types.length,
 965                                                        spnego_state->mech_types.data,
 966                                                        spnego_state->mech_types.length,
 967                                                        &mech_list_mic);
 968                         if (!NT_STATUS_IS_OK(nt_status)) {
 969                                 DEBUG(2,("GENSEC SPNEGO: failed to sign mechListMIC: %s\n",
 970                                         nt_errstr(nt_status)));
 971                         }
 972                 }
 973
 974                 nt_status = gensec_spnego_server_negTokenTarg(spnego_state,
 975                                                               out_mem_ctx,
 976                                                               nt_status,
 977                                                               unwrapped_out,
 978                                                               mech_list_mic,
 979                                                               out);
 980
 981                 spnego_free_data(&spnego);
 982
 983                 return nt_status;
 984         }
 985         case SPNEGO_CLIENT_TARG:
 986         {
 987                 NTSTATUS nt_status;
 988                 if (!in.length) {
 989                         return NT_STATUS_INVALID_PARAMETER;
 990                 }
 991
 992                 len = spnego_read_data(gensec_security, in, &spnego);
 993
 994                 if (len == -1) {
 995                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 996                         dump_data(1, in.data, in.length);
 997                         return NT_STATUS_INVALID_PARAMETER;
 998                 }
 999
1000                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
1001                 if (spnego.type != spnego_state->expected_packet) {
1002                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
1003                                   spnego_state->expected_packet));
1004                         dump_data(1, in.data, in.length);
1005                         spnego_free_data(&spnego);
1006                         return NT_STATUS_INVALID_PARAMETER;
1007                 }
1008
1009                 if (spnego.negTokenTarg.negResult == SPNEGO_REJECT) {
1010                         spnego_free_data(&spnego);
1011                         return NT_STATUS_ACCESS_DENIED;
1012                 }
1013
1014                 /* Server didn't like our choice of mech, and chose something else */
1015                 if ((spnego.negTokenTarg.negResult == SPNEGO_ACCEPT_INCOMPLETE) &&
1016                     spnego.negTokenTarg.supportedMech &&
1017                     strcmp(spnego.negTokenTarg.supportedMech, spnego_state->neg_oid) != 0) {
1018                         DEBUG(3,("GENSEC SPNEGO: client preferred mech (%s) not accepted, server wants: %s\n",
1019                                  gensec_get_name_by_oid(gensec_security, spnego.negTokenTarg.supportedMech),
1020                                  gensec_get_name_by_oid(gensec_security, spnego_state->neg_oid)));
1021
1022                         talloc_free(spnego_state->sub_sec_security);
1023                         nt_status = gensec_subcontext_start(spnego_state,
1024                                                             gensec_security,
1025                                                             &spnego_state->sub_sec_security);
1026                         if (!NT_STATUS_IS_OK(nt_status)) {
1027                                 spnego_free_data(&spnego);
1028                                 return nt_status;
1029                         }
1030                         /* select the sub context */
1031                         nt_status = gensec_start_mech_by_oid(spnego_state->sub_sec_security,
1032                                                              spnego.negTokenTarg.supportedMech);
1033                         if (!NT_STATUS_IS_OK(nt_status)) {
1034                                 spnego_free_data(&spnego);
1035                                 return nt_status;
1036                         }
1037
1038                         nt_status = gensec_update(spnego_state->sub_sec_security,
1039                                                   out_mem_ctx, ev,
1040                                                   spnego.negTokenTarg.responseToken,
1041                                                   &unwrapped_out);
1042                         spnego_state->neg_oid = talloc_strdup(spnego_state, spnego.negTokenTarg.supportedMech);
1043                 } else if (spnego_state->no_response_expected) {
1044                         if (spnego.negTokenTarg.negResult != SPNEGO_ACCEPT_COMPLETED) {
1045                                 DEBUG(3,("GENSEC SPNEGO: client GENSEC accepted, but server rejected (bad password?)\n"));
1046                                 nt_status = NT_STATUS_INVALID_PARAMETER;
1047                         } else if (spnego.negTokenTarg.responseToken.length) {
1048                                 DEBUG(2,("GENSEC SPNEGO: client GENSEC accepted, but server continued negotiation!\n"));
1049                                 nt_status = NT_STATUS_INVALID_PARAMETER;
1050                         } else {
1051                                 nt_status = NT_STATUS_OK;
1052                         }
1053                         if (NT_STATUS_IS_OK(nt_status) && spnego.negTokenTarg.mechListMIC.length > 0) {
1054                                 nt_status = gensec_check_packet(spnego_state->sub_sec_security,
1055                                                                 spnego_state->mech_types.data,
1056                                                                 spnego_state->mech_types.length,
1057                                                                 spnego_state->mech_types.data,
1058                                                                 spnego_state->mech_types.length,
1059                                                                 &spnego.negTokenTarg.mechListMIC);
1060                                 if (!NT_STATUS_IS_OK(nt_status)) {
1061                                         DEBUG(2,("GENSEC SPNEGO: failed to verify mechListMIC: %s\n",
1062                                                 nt_errstr(nt_status)));
1063                                 }
1064                         }
1065                 } else {
1066                         bool new_spnego = false;
1067
1068                         nt_status = gensec_update(spnego_state->sub_sec_security,
1069                                                   out_mem_ctx, ev,
1070                                                   spnego.negTokenTarg.responseToken,
1071                                                   &unwrapped_out);
1072
1073                         if (NT_STATUS_IS_OK(nt_status)
1074                             && spnego.negTokenTarg.negResult != SPNEGO_ACCEPT_COMPLETED) {
1075                                 new_spnego = gensec_have_feature(spnego_state->sub_sec_security,
1076                                                                  GENSEC_FEATURE_NEW_SPNEGO);
1077                         }
1078                         if (NT_STATUS_IS_OK(nt_status) && new_spnego) {
1079                                 nt_status = gensec_sign_packet(spnego_state->sub_sec_security,
1080                                                                out_mem_ctx,
1081                                                                spnego_state->mech_types.data,
1082                                                                spnego_state->mech_types.length,
1083                                                                spnego_state->mech_types.data,
1084                                                                spnego_state->mech_types.length,
1085                                                                &mech_list_mic);
1086                                 if (!NT_STATUS_IS_OK(nt_status)) {
1087                                         DEBUG(2,("GENSEC SPNEGO: failed to sign mechListMIC: %s\n",
1088                                                 nt_errstr(nt_status)));
1089                                 }
1090                         }
1091                         if (NT_STATUS_IS_OK(nt_status)) {
1092                                 spnego_state->no_response_expected = true;
1093                         }
1094                 }
1095
1096                 spnego_free_data(&spnego);
1097
1098                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
1099                         && !NT_STATUS_IS_OK(nt_status)) {
1100                         DEBUG(1, ("SPNEGO(%s) login failed: %s\n",
1101                                   spnego_state->sub_sec_security->ops->name,
1102                                   nt_errstr(nt_status)));
1103                         return nt_status;
1104                 }
1105
1106                 if (unwrapped_out.length || mech_list_mic.length) {
1107                         /* compose reply */
1108                         spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
1109                         spnego_out.negTokenTarg.negResult = SPNEGO_NONE_RESULT;
1110                         spnego_out.negTokenTarg.supportedMech = NULL;
1111                         spnego_out.negTokenTarg.responseToken = unwrapped_out;
1112                         spnego_out.negTokenTarg.mechListMIC = mech_list_mic;
1113
1114                         if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
1115                                 DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
1116                                 return NT_STATUS_INVALID_PARAMETER;
1117                         }
1118
1119                         spnego_state->state_position = SPNEGO_CLIENT_TARG;
1120                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
1121                 } else {
1122
1123                         /* all done - server has accepted, and we agree */
1124                         *out = null_data_blob;
1125
1126                         if (spnego.negTokenTarg.negResult != SPNEGO_ACCEPT_COMPLETED) {
1127                                 /* unless of course it did not accept */
1128                                 DEBUG(1,("gensec_update ok but not accepted\n"));
1129                                 nt_status = NT_STATUS_INVALID_PARAMETER;
1130                         }
1131
1132                         spnego_state->state_position = SPNEGO_DONE;
1133                 }
1134
1135                 return nt_status;
1136         }
1137         case SPNEGO_DONE:
1138                 /* We should not be called after we are 'done' */
1139                 return NT_STATUS_INVALID_PARAMETER;
1140         }
1141         return NT_STATUS_INVALID_PARAMETER;
1142 }
1143
1144 static NTSTATUS gensec_spnego_update_in(struct gensec_security *gensec_security,
1145                                         const DATA_BLOB in, DATA_BLOB *full_in)
1146 {
1147         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1148         size_t expected;
1149         NTSTATUS status;
1150         bool ok;
1151
1152         *full_in = data_blob_null;
1153
1154         if (spnego_state->in_needed == 0) {
1155                 size_t size = 0;
1156
1157                 /*
1158                  * try to work out the size of the full
1159                  * input token, it might be fragmented
1160                  */
1161                 status = asn1_peek_full_tag(in,  ASN1_APPLICATION(0), &size);
1162                 if (!NT_STATUS_IS_OK(status) &&
1163                     !NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) {
1164                         status = asn1_peek_full_tag(in, ASN1_CONTEXT(1), &size);
1165                 }
1166
1167                 if (NT_STATUS_IS_OK(status) ||
1168                     NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) {
1169                         spnego_state->in_needed = size;
1170                 } else {
1171                         /*
1172                          * If it is not an asn1 message
1173                          * just call the next layer.
1174                          */
1175                         spnego_state->in_needed = in.length;
1176                 }
1177         }
1178
1179         if (spnego_state->in_needed > UINT16_MAX) {
1180                 /*
1181                  * limit the incoming message to 0xFFFF
1182                  * to avoid DoS attacks.
1183                  */
1184                 return NT_STATUS_INVALID_BUFFER_SIZE;
1185         }
1186
1187         if ((spnego_state->in_needed > 0) && (in.length == 0)) {
1188                 /*
1189                  * If we reach this, we know we got at least
1190                  * part of an asn1 message, getting 0 means
1191                  * the remote peer wants us to spin.
1192                  */
1193                 return NT_STATUS_INVALID_PARAMETER;
1194         }
1195
1196         expected = spnego_state->in_needed - spnego_state->in_frag.length;
1197         if (in.length > expected) {
1198                 /*
1199                  * we got more than expected
1200                  */
1201                 return NT_STATUS_INVALID_PARAMETER;
1202         }
1203
1204         if (in.length == spnego_state->in_needed) {
1205                 /*
1206                  * if the in.length contains the full blob
1207                  * we are done.
1208                  *
1209                  * Note: this implies spnego_state->in_frag.length == 0,
1210                  *       but we do not need to check this explicitly
1211                  *       because we already know that we did not get
1212                  *       more than expected.
1213                  */
1214                 *full_in = in;
1215                 return NT_STATUS_OK;
1216         }
1217
1218         ok = data_blob_append(spnego_state, &spnego_state->in_frag,
1219                               in.data, in.length);
1220         if (!ok) {
1221                 return NT_STATUS_NO_MEMORY;
1222         }
1223
1224         if (spnego_state->in_needed > spnego_state->in_frag.length) {
1225                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
1226         }
1227
1228         *full_in = spnego_state->in_frag;
1229         return NT_STATUS_OK;
1230 }
1231
1232 static NTSTATUS gensec_spnego_update_out(struct gensec_security *gensec_security,
1233                                          TALLOC_CTX *out_mem_ctx,
1234                                          DATA_BLOB *_out)
1235 {
1236         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1237         DATA_BLOB out = data_blob_null;
1238
1239         *_out = data_blob_null;
1240
1241         if (spnego_state->out_frag.length == 0) {
1242                 return spnego_state->out_status;
1243         }
1244
1245         /*
1246          * There is still more data to be delivered
1247          * to the remote peer.
1248          */
1249
1250         if (spnego_state->out_frag.length <= spnego_state->out_max_length) {
1251                 /*
1252                  * Fast path, we can deliver everything
1253                  */
1254
1255                 *_out = spnego_state->out_frag;
1256                 talloc_steal(out_mem_ctx, _out->data);
1257                 spnego_state->out_frag = data_blob_null;
1258                 return spnego_state->out_status;
1259         }
1260
1261         out = spnego_state->out_frag;
1262
1263         /*
1264          * copy the remaining bytes
1265          */
1266         spnego_state->out_frag = data_blob_talloc(spnego_state,
1267                                         out.data + spnego_state->out_max_length,
1268                                         out.length - spnego_state->out_max_length);
1269         if (spnego_state->out_frag.data == NULL) {
1270                 return NT_STATUS_NO_MEMORY;
1271         }
1272
1273         /*
1274          * truncate the buffer
1275          */
1276         data_blob_realloc(spnego_state, &out, spnego_state->out_max_length);
1277
1278         talloc_steal(out_mem_ctx, out.data);
1279         *_out = out;
1280         return NT_STATUS_MORE_PROCESSING_REQUIRED;
1281 }
1282
1283 static NTSTATUS gensec_spnego_update_wrapper(struct gensec_security *gensec_security,
1284                                              TALLOC_CTX *out_mem_ctx,
1285                                              struct tevent_context *ev,
1286                                              const DATA_BLOB in, DATA_BLOB *out)
1287 {
1288         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1289         DATA_BLOB full_in = data_blob_null;
1290         NTSTATUS status;
1291
1292         *out = data_blob_null;
1293
1294         if (spnego_state->out_frag.length > 0) {
1295                 if (in.length > 0) {
1296                         return NT_STATUS_INVALID_PARAMETER;
1297                 }
1298
1299                 return gensec_spnego_update_out(gensec_security,
1300                                                 out_mem_ctx,
1301                                                 out);
1302         }
1303
1304         status = gensec_spnego_update_in(gensec_security,
1305                                          in, &full_in);
1306         if (!NT_STATUS_IS_OK(status)) {
1307                 return status;
1308         }
1309
1310         status = gensec_spnego_update(gensec_security,
1311                                       spnego_state, ev,
1312                                       full_in,
1313                                       &spnego_state->out_frag);
1314         data_blob_free(&spnego_state->in_frag);
1315         spnego_state->in_needed = 0;
1316         if (!NT_STATUS_IS_OK(status) &&
1317             !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
1318                 return status;
1319         }
1320
1321         spnego_state->out_status = status;
1322
1323         return gensec_spnego_update_out(gensec_security,
1324                                         out_mem_ctx,
1325                                         out);
1326 }
1327
1328 static void gensec_spnego_want_feature(struct gensec_security *gensec_security,
1329                                        uint32_t feature)
1330 {
1331         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1332
1333         if (!spnego_state || !spnego_state->sub_sec_security) {
1334                 gensec_security->want_features |= feature;
1335                 return;
1336         }
1337
1338         gensec_want_feature(spnego_state->sub_sec_security,
1339                             feature);
1340 }
1341
1342 static bool gensec_spnego_have_feature(struct gensec_security *gensec_security,
1343                                        uint32_t feature)
1344 {
1345         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1346         if (!spnego_state->sub_sec_security) {
1347                 return false;
1348         }
1349
1350         return gensec_have_feature(spnego_state->sub_sec_security,
1351                                    feature);
1352 }
1353
1354 static NTTIME gensec_spnego_expire_time(struct gensec_security *gensec_security)
1355 {
1356         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1357
1358         if (!spnego_state->sub_sec_security) {
1359                 return GENSEC_EXPIRE_TIME_INFINITY;
1360         }
1361
1362         return gensec_expire_time(spnego_state->sub_sec_security);
1363 }
1364
1365 static const char *gensec_spnego_oids[] = {
1366         GENSEC_OID_SPNEGO,
1367         NULL
1368 };
1369
1370 static const struct gensec_security_ops gensec_spnego_security_ops = {
1371         .name             = "spnego",
1372         .sasl_name        = "GSS-SPNEGO",
1373         .auth_type        = DCERPC_AUTH_TYPE_SPNEGO,
1374         .oid              = gensec_spnego_oids,
1375         .client_start     = gensec_spnego_client_start,
1376         .server_start     = gensec_spnego_server_start,
1377         .update           = gensec_spnego_update_wrapper,
1378         .seal_packet      = gensec_spnego_seal_packet,
1379         .sign_packet      = gensec_spnego_sign_packet,
1380         .sig_size         = gensec_spnego_sig_size,
1381         .max_wrapped_size = gensec_spnego_max_wrapped_size,
1382         .max_input_size   = gensec_spnego_max_input_size,
1383         .check_packet     = gensec_spnego_check_packet,
1384         .unseal_packet    = gensec_spnego_unseal_packet,
1385         .packet_full_request = gensec_spnego_packet_full_request,
1386         .wrap             = gensec_spnego_wrap,
1387         .unwrap           = gensec_spnego_unwrap,
1388         .wrap_packets     = gensec_spnego_wrap_packets,
1389         .unwrap_packets   = gensec_spnego_unwrap_packets,
1390         .session_key      = gensec_spnego_session_key,
1391         .session_info     = gensec_spnego_session_info,
1392         .want_feature     = gensec_spnego_want_feature,
1393         .have_feature     = gensec_spnego_have_feature,
1394         .expire_time      = gensec_spnego_expire_time,
1395         .enabled          = true,
1396         .priority         = GENSEC_SPNEGO
1397 };
1398
1399 _PUBLIC_ NTSTATUS gensec_spnego_init(void)
1400 {
1401         NTSTATUS ret;
1402         ret = gensec_register(&gensec_spnego_security_ops);
1403         if (!NT_STATUS_IS_OK(ret)) {
1404                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1405                         gensec_spnego_security_ops.name));
1406                 return ret;
1407         }
1408
1409         return ret;
1410 }