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         const struct gensec_security_ops **all_ops;
 356
 357         all_ops = gensec_security_mechs(gensec_security, out_mem_ctx);
 358
 359         for (i=0; all_ops && all_ops[i]; i++) {
 360                 bool is_spnego;
 361                 NTSTATUS nt_status;
 362
 363                 if (gensec_security != NULL &&
 364                                 !gensec_security_ops_enabled(all_ops[i], gensec_security))
 365                     continue;
 366
 367                 if (!all_ops[i]->oid) {
 368                         continue;
 369                 }
 370
 371                 is_spnego = false;
 372                 for (j=0; all_ops[i]->oid[j]; j++) {
 373                         if (strcasecmp(GENSEC_OID_SPNEGO,all_ops[i]->oid[j]) == 0) {
 374                                 is_spnego = true;
 375                         }
 376                 }
 377                 if (is_spnego) {
 378                         continue;
 379                 }
 380
 381                 if (!all_ops[i]->magic) {
 382                         continue;
 383                 }
 384
 385                 nt_status = all_ops[i]->magic(gensec_security, &in);
 386                 if (!NT_STATUS_IS_OK(nt_status)) {
 387                         continue;
 388                 }
 389
 390                 spnego_state->state_position = SPNEGO_FALLBACK;
 391
 392                 nt_status = gensec_subcontext_start(spnego_state,
 393                                                     gensec_security,
 394                                                     &spnego_state->sub_sec_security);
 395
 396                 if (!NT_STATUS_IS_OK(nt_status)) {
 397                         return nt_status;
 398                 }
 399                 /* select the sub context */
 400                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 401                                                      all_ops[i]);
 402                 if (!NT_STATUS_IS_OK(nt_status)) {
 403                         return nt_status;
 404                 }
 405                 nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 406                                           ev, out_mem_ctx, in, out);
 407                 return nt_status;
 408         }
 409         DEBUG(1, ("Failed to parse SPNEGO request\n"));
 410         return NT_STATUS_INVALID_PARAMETER;
 411 }
 412
 413 /*
 414    Parse the netTokenInit, either from the client, to the server, or
 415    from the server to the client.
 416 */
 417
 418 static NTSTATUS gensec_spnego_parse_negTokenInit(struct gensec_security *gensec_security,
 419                                                  struct spnego_state *spnego_state,
 420                                                  TALLOC_CTX *out_mem_ctx,
 421                                                  struct tevent_context *ev,
 422                                                  const char * const *mechType,
 423                                                  const DATA_BLOB unwrapped_in, DATA_BLOB *unwrapped_out)
 424 {
 425         int i;
 426         NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 427         DATA_BLOB null_data_blob = data_blob(NULL,0);
 428         bool ok;
 429
 430         const struct gensec_security_ops_wrapper *all_sec
 431                 = gensec_security_by_oid_list(gensec_security,
 432                                               out_mem_ctx,
 433                                               mechType,
 434                                               GENSEC_OID_SPNEGO);
 435
 436         ok = spnego_write_mech_types(spnego_state,
 437                                      mechType,
 438                                      &spnego_state->mech_types);
 439         if (!ok) {
 440                 DEBUG(1, ("SPNEGO: Failed to write mechTypes\n"));
 441                 return NT_STATUS_NO_MEMORY;
 442         }
 443
 444         if (spnego_state->state_position == SPNEGO_SERVER_START) {
 445                 uint32_t j;
 446                 for (j=0; mechType && mechType[j]; j++) {
 447                         for (i=0; all_sec && all_sec[i].op; i++) {
 448                                 if (strcmp(mechType[j], all_sec[i].oid) != 0) {
 449                                         continue;
 450                                 }
 451
 452                                 nt_status = gensec_subcontext_start(spnego_state,
 453                                                                     gensec_security,
 454                                                                     &spnego_state->sub_sec_security);
 455                                 if (!NT_STATUS_IS_OK(nt_status)) {
 456                                         return nt_status;
 457                                 }
 458                                 /* select the sub context */
 459                                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 460                                                                      all_sec[i].op);
 461                                 if (!NT_STATUS_IS_OK(nt_status)) {
 462                                         talloc_free(spnego_state->sub_sec_security);
 463                                         spnego_state->sub_sec_security = NULL;
 464                                         break;
 465                                 }
 466
 467                                 if (j > 0) {
 468                                         /* no optimistic token */
 469                                         spnego_state->neg_oid = all_sec[i].oid;
 470                                         *unwrapped_out = data_blob_null;
 471                                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 472                                         break;
 473                                 }
 474
 475                                 nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 476                                                           out_mem_ctx,
 477                                                           ev,
 478                                                           unwrapped_in,
 479                                                           unwrapped_out);
 480                                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER) ||
 481                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_CANT_ACCESS_DOMAIN_INFO)) {
 482                                         /* Pretend we never started it (lets the first run find some incompatible demand) */
 483
 484                                         DEBUG(1, ("SPNEGO(%s) NEG_TOKEN_INIT failed to parse contents: %s\n",
 485                                                   spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 486                                         talloc_free(spnego_state->sub_sec_security);
 487                                         spnego_state->sub_sec_security = NULL;
 488                                         break;
 489                                 }
 490
 491                                 spnego_state->neg_oid = all_sec[i].oid;
 492                                 break;
 493                         }
 494                         if (spnego_state->sub_sec_security) {
 495                                 break;
 496                         }
 497                 }
 498
 499                 if (!spnego_state->sub_sec_security) {
 500                         DEBUG(1, ("SPNEGO: Could not find a suitable mechtype in NEG_TOKEN_INIT\n"));
 501                         return NT_STATUS_INVALID_PARAMETER;
 502                 }
 503         }
 504
 505         /* Having tried any optimistic token from the client (if we
 506          * were the server), if we didn't get anywhere, walk our list
 507          * in our preference order */
 508
 509         if (!spnego_state->sub_sec_security) {
 510                 for (i=0; all_sec && all_sec[i].op; i++) {
 511                         nt_status = gensec_subcontext_start(spnego_state,
 512                                                             gensec_security,
 513                                                             &spnego_state->sub_sec_security);
 514                         if (!NT_STATUS_IS_OK(nt_status)) {
 515                                 return nt_status;
 516                         }
 517                         /* select the sub context */
 518                         nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 519                                                              all_sec[i].op);
 520                         if (!NT_STATUS_IS_OK(nt_status)) {
 521                                 talloc_free(spnego_state->sub_sec_security);
 522                                 spnego_state->sub_sec_security = NULL;
 523                                 continue;
 524                         }
 525
 526                         spnego_state->neg_oid = all_sec[i].oid;
 527
 528                         /* only get the helping start blob for the first OID */
 529                         nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 530                                                   out_mem_ctx,
 531                                                   ev,
 532                                                   null_data_blob,
 533                                                   unwrapped_out);
 534
 535                         /* it is likely that a NULL input token will
 536                          * not be liked by most server mechs, but if
 537                          * we are in the client, we want the first
 538                          * update packet to be able to abort the use
 539                          * of this mech */
 540                         if (spnego_state->state_position != SPNEGO_SERVER_START) {
 541                                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER) ||
 542                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_LOGON_SERVERS) ||
 543                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_TIME_DIFFERENCE_AT_DC) ||
 544                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_CANT_ACCESS_DOMAIN_INFO)) {
 545                                         /* Pretend we never started it (lets the first run find some incompatible demand) */
 546
 547                                         DEBUG(3, ("SPNEGO(%s) NEG_TOKEN_INIT failed: %s\n",
 548                                                   spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 549                                         talloc_free(spnego_state->sub_sec_security);
 550                                         spnego_state->sub_sec_security = NULL;
 551                                         continue;
 552                                 }
 553                         }
 554
 555                         break;
 556                 }
 557         }
 558
 559         if (spnego_state->sub_sec_security) {
 560                 /* it is likely that a NULL input token will
 561                  * not be liked by most server mechs, but this
 562                  * does the right thing in the CIFS client.
 563                  * just push us along the merry-go-round
 564                  * again, and hope for better luck next
 565                  * time */
 566
 567                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER)) {
 568                         *unwrapped_out = data_blob(NULL, 0);
 569                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 570                 }
 571
 572                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER)
 573                     && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
 574                     && !NT_STATUS_IS_OK(nt_status)) {
 575                         DEBUG(1, ("SPNEGO(%s) NEG_TOKEN_INIT failed: %s\n",
 576                                   spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 577                         talloc_free(spnego_state->sub_sec_security);
 578                         spnego_state->sub_sec_security = NULL;
 579
 580                         /* We started the mech correctly, and the
 581                          * input from the other side was valid.
 582                          * Return the error (say bad password, invalid
 583                          * ticket) */
 584                         return nt_status;
 585                 }
 586
 587                 return nt_status; /* OK, INVALID_PARAMETER ore MORE PROCESSING */
 588         }
 589
 590         DEBUG(1, ("SPNEGO: Could not find a suitable mechtype in NEG_TOKEN_INIT\n"));
 591         /* we could re-negotiate here, but it would only work
 592          * if the client or server lied about what it could
 593          * support the first time.  Lets keep this code to
 594          * reality */
 595
 596         return nt_status;
 597 }
 598
 599 /** create a negTokenInit
 600  *
 601  * This is the same packet, no matter if the client or server sends it first, but it is always the first packet
 602 */
 603 static NTSTATUS gensec_spnego_create_negTokenInit(struct gensec_security *gensec_security,
 604                                                   struct spnego_state *spnego_state,
 605                                                   TALLOC_CTX *out_mem_ctx,
 606                                                   struct tevent_context *ev,
 607                                                   const DATA_BLOB in, DATA_BLOB *out)
 608 {
 609         int i;
 610         NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 611         DATA_BLOB null_data_blob = data_blob(NULL,0);
 612         const char **mechTypes = NULL;
 613         DATA_BLOB unwrapped_out = data_blob(NULL, 0);
 614         const struct gensec_security_ops_wrapper *all_sec;
 615
 616         mechTypes = gensec_security_oids(gensec_security,
 617                                          out_mem_ctx, GENSEC_OID_SPNEGO);
 618
 619         all_sec = gensec_security_by_oid_list(gensec_security,
 620                                               out_mem_ctx,
 621                                               mechTypes,
 622                                               GENSEC_OID_SPNEGO);
 623         for (i=0; all_sec && all_sec[i].op; i++) {
 624                 struct spnego_data spnego_out;
 625                 const char **send_mech_types;
 626                 bool ok;
 627
 628                 nt_status = gensec_subcontext_start(spnego_state,
 629                                                     gensec_security,
 630                                                     &spnego_state->sub_sec_security);
 631                 if (!NT_STATUS_IS_OK(nt_status)) {
 632                         return nt_status;
 633                 }
 634                 /* select the sub context */
 635                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 636                                                      all_sec[i].op);
 637                 if (!NT_STATUS_IS_OK(nt_status)) {
 638                         talloc_free(spnego_state->sub_sec_security);
 639                         spnego_state->sub_sec_security = NULL;
 640                         continue;
 641                 }
 642
 643                 /* In the client, try and produce the first (optimistic) packet */
 644                 if (spnego_state->state_position == SPNEGO_CLIENT_START) {
 645                         nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 646                                                   out_mem_ctx,
 647                                                   ev,
 648                                                   null_data_blob,
 649                                                   &unwrapped_out);
 650
 651                         if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
 652                             && !NT_STATUS_IS_OK(nt_status)) {
 653                                 DEBUG(1, ("SPNEGO(%s) creating NEG_TOKEN_INIT failed: %s\n",
 654                                           spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 655                                 talloc_free(spnego_state->sub_sec_security);
 656                                 spnego_state->sub_sec_security = NULL;
 657                                 /* Pretend we never started it (lets the first run find some incompatible demand) */
 658
 659                                 continue;
 660                         }
 661                 }
 662
 663                 spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 664
 665                 send_mech_types = gensec_security_oids_from_ops_wrapped(out_mem_ctx,
 666                                                                         &all_sec[i]);
 667
 668                 ok = spnego_write_mech_types(spnego_state,
 669                                              send_mech_types,
 670                                              &spnego_state->mech_types);
 671                 if (!ok) {
 672                         DEBUG(1, ("SPNEGO: Failed to write mechTypes\n"));
 673                         return NT_STATUS_NO_MEMORY;
 674                 }
 675
 676                 /* List the remaining mechs as options */
 677                 spnego_out.negTokenInit.mechTypes = send_mech_types;
 678                 spnego_out.negTokenInit.reqFlags = null_data_blob;
 679                 spnego_out.negTokenInit.reqFlagsPadding = 0;
 680
 681                 if (spnego_state->state_position == SPNEGO_SERVER_START) {
 682                         spnego_out.negTokenInit.mechListMIC
 683                                 = data_blob_string_const(ADS_IGNORE_PRINCIPAL);
 684                 } else {
 685                         spnego_out.negTokenInit.mechListMIC = null_data_blob;
 686                 }
 687
 688                 spnego_out.negTokenInit.mechToken = unwrapped_out;
 689
 690                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 691                         DEBUG(1, ("Failed to write NEG_TOKEN_INIT\n"));
 692                                 return NT_STATUS_INVALID_PARAMETER;
 693                 }
 694
 695                 /* set next state */
 696                 spnego_state->neg_oid = all_sec[i].oid;
 697
 698                 if (NT_STATUS_IS_OK(nt_status)) {
 699                         spnego_state->no_response_expected = true;
 700                 }
 701
 702                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 703         }
 704         talloc_free(spnego_state->sub_sec_security);
 705         spnego_state->sub_sec_security = NULL;
 706
 707         DEBUG(1, ("Failed to setup SPNEGO negTokenInit request: %s\n", nt_errstr(nt_status)));
 708         return nt_status;
 709 }
 710
 711
 712 /** create a server negTokenTarg
 713  *
 714  * This is the case, where the client is the first one who sends data
 715 */
 716
 717 static NTSTATUS gensec_spnego_server_negTokenTarg(struct spnego_state *spnego_state,
 718                                                   TALLOC_CTX *out_mem_ctx,
 719                                                   NTSTATUS nt_status,
 720                                                   const DATA_BLOB unwrapped_out,
 721                                                   DATA_BLOB mech_list_mic,
 722                                                   DATA_BLOB *out)
 723 {
 724         struct spnego_data spnego_out;
 725         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 726
 727         /* compose reply */
 728         spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
 729         spnego_out.negTokenTarg.responseToken = unwrapped_out;
 730         spnego_out.negTokenTarg.mechListMIC = null_data_blob;
 731         spnego_out.negTokenTarg.supportedMech = NULL;
 732
 733         if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 734                 spnego_out.negTokenTarg.supportedMech = spnego_state->neg_oid;
 735                 spnego_out.negTokenTarg.negResult = SPNEGO_ACCEPT_INCOMPLETE;
 736                 spnego_state->state_position = SPNEGO_SERVER_TARG;
 737         } else if (NT_STATUS_IS_OK(nt_status)) {
 738                 if (unwrapped_out.data) {
 739                         spnego_out.negTokenTarg.supportedMech = spnego_state->neg_oid;
 740                 }
 741                 spnego_out.negTokenTarg.negResult = SPNEGO_ACCEPT_COMPLETED;
 742                 spnego_out.negTokenTarg.mechListMIC = mech_list_mic;
 743                 spnego_state->state_position = SPNEGO_DONE;
 744         } else {
 745                 spnego_out.negTokenTarg.negResult = SPNEGO_REJECT;
 746                 DEBUG(2, ("SPNEGO login failed: %s\n", nt_errstr(nt_status)));
 747                 spnego_state->state_position = SPNEGO_DONE;
 748         }
 749
 750         if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 751                 DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
 752                 return NT_STATUS_INVALID_PARAMETER;
 753         }
 754
 755         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 756
 757         return nt_status;
 758 }
 759
 760
 761 static NTSTATUS gensec_spnego_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx,
 762                                      struct tevent_context *ev,
 763                                      const DATA_BLOB in, DATA_BLOB *out)
 764 {
 765         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 766         DATA_BLOB null_data_blob = data_blob(NULL, 0);
 767         DATA_BLOB mech_list_mic = data_blob(NULL, 0);
 768         DATA_BLOB unwrapped_out = data_blob(NULL, 0);
 769         struct spnego_data spnego_out;
 770         struct spnego_data spnego;
 771
 772         ssize_t len;
 773
 774         *out = data_blob(NULL, 0);
 775
 776         if (!out_mem_ctx) {
 777                 out_mem_ctx = spnego_state;
 778         }
 779
 780         /* and switch into the state machine */
 781
 782         switch (spnego_state->state_position) {
 783         case SPNEGO_FALLBACK:
 784                 return gensec_update_ev(spnego_state->sub_sec_security, ev,
 785                                      out_mem_ctx, in, out);
 786         case SPNEGO_SERVER_START:
 787         {
 788                 NTSTATUS nt_status;
 789                 if (in.length) {
 790
 791                         len = spnego_read_data(gensec_security, in, &spnego);
 792                         if (len == -1) {
 793                                 return gensec_spnego_server_try_fallback(gensec_security, spnego_state,
 794                                                                          out_mem_ctx, ev, in, out);
 795                         }
 796                         /* client sent NegTargetInit, we send NegTokenTarg */
 797
 798                         /* OK, so it's real SPNEGO, check the packet's the one we expect */
 799                         if (spnego.type != spnego_state->expected_packet) {
 800                                 DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 801                                           spnego_state->expected_packet));
 802                                 dump_data(1, in.data, in.length);
 803                                 spnego_free_data(&spnego);
 804                                 return NT_STATUS_INVALID_PARAMETER;
 805                         }
 806
 807                         nt_status = gensec_spnego_parse_negTokenInit(gensec_security,
 808                                                                      spnego_state,
 809                                                                      out_mem_ctx,
 810                                                                      ev,
 811                                                                      spnego.negTokenInit.mechTypes,
 812                                                                      spnego.negTokenInit.mechToken,
 813                                                                      &unwrapped_out);
 814
 815                         nt_status = gensec_spnego_server_negTokenTarg(spnego_state,
 816                                                                       out_mem_ctx,
 817                                                                       nt_status,
 818                                                                       unwrapped_out,
 819                                                                       null_data_blob,
 820                                                                       out);
 821
 822                         spnego_free_data(&spnego);
 823
 824                         return nt_status;
 825                 } else {
 826                         nt_status = gensec_spnego_create_negTokenInit(gensec_security, spnego_state,
 827                                                                       out_mem_ctx, ev, in, out);
 828                         spnego_state->state_position = SPNEGO_SERVER_START;
 829                         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_INIT;
 830                         return nt_status;
 831                 }
 832         }
 833
 834         case SPNEGO_CLIENT_START:
 835         {
 836                 /* The server offers a list of mechanisms */
 837
 838                 const char *my_mechs[] = {NULL, NULL};
 839                 NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 840
 841                 if (!in.length) {
 842                         /* client to produce negTokenInit */
 843                         nt_status = gensec_spnego_create_negTokenInit(gensec_security, spnego_state,
 844                                                                       out_mem_ctx, ev, in, out);
 845                         spnego_state->state_position = SPNEGO_CLIENT_TARG;
 846                         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 847                         return nt_status;
 848                 }
 849
 850                 len = spnego_read_data(gensec_security, in, &spnego);
 851
 852                 if (len == -1) {
 853                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 854                         dump_data(1, in.data, in.length);
 855                         return NT_STATUS_INVALID_PARAMETER;
 856                 }
 857
 858                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 859                 if (spnego.type != spnego_state->expected_packet) {
 860                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 861                                   spnego_state->expected_packet));
 862                         dump_data(1, in.data, in.length);
 863                         spnego_free_data(&spnego);
 864                         return NT_STATUS_INVALID_PARAMETER;
 865                 }
 866
 867                 if (spnego.negTokenInit.targetPrincipal
 868                     && strcmp(spnego.negTokenInit.targetPrincipal, ADS_IGNORE_PRINCIPAL) != 0) {
 869                         DEBUG(5, ("Server claims it's principal name is %s\n", spnego.negTokenInit.targetPrincipal));
 870                         if (lpcfg_client_use_spnego_principal(gensec_security->settings->lp_ctx)) {
 871                                 gensec_set_target_principal(gensec_security, spnego.negTokenInit.targetPrincipal);
 872                         }
 873                 }
 874
 875                 nt_status = gensec_spnego_parse_negTokenInit(gensec_security,
 876                                                              spnego_state,
 877                                                              out_mem_ctx,
 878                                                              ev,
 879                                                              spnego.negTokenInit.mechTypes,
 880                                                              spnego.negTokenInit.mechToken,
 881                                                              &unwrapped_out);
 882
 883                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(nt_status)) {
 884                         spnego_free_data(&spnego);
 885                         return nt_status;
 886                 }
 887
 888                 my_mechs[0] = spnego_state->neg_oid;
 889                 /* compose reply */
 890                 spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 891                 spnego_out.negTokenInit.mechTypes = my_mechs;
 892                 spnego_out.negTokenInit.reqFlags = null_data_blob;
 893                 spnego_out.negTokenInit.reqFlagsPadding = 0;
 894                 spnego_out.negTokenInit.mechListMIC = null_data_blob;
 895                 spnego_out.negTokenInit.mechToken = unwrapped_out;
 896
 897                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 898                         DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_INIT\n"));
 899                                 return NT_STATUS_INVALID_PARAMETER;
 900                 }
 901
 902                 /* set next state */
 903                 spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 904                 spnego_state->state_position = SPNEGO_CLIENT_TARG;
 905
 906                 if (NT_STATUS_IS_OK(nt_status)) {
 907                         spnego_state->no_response_expected = true;
 908                 }
 909
 910                 spnego_free_data(&spnego);
 911                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 912         }
 913         case SPNEGO_SERVER_TARG:
 914         {
 915                 NTSTATUS nt_status;
 916                 bool new_spnego = false;
 917
 918                 if (!in.length) {
 919                         return NT_STATUS_INVALID_PARAMETER;
 920                 }
 921
 922                 len = spnego_read_data(gensec_security, in, &spnego);
 923
 924                 if (len == -1) {
 925                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 926                         dump_data(1, in.data, in.length);
 927                         return NT_STATUS_INVALID_PARAMETER;
 928                 }
 929
 930                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 931                 if (spnego.type != spnego_state->expected_packet) {
 932                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 933                                   spnego_state->expected_packet));
 934                         dump_data(1, in.data, in.length);
 935                         spnego_free_data(&spnego);
 936                         return NT_STATUS_INVALID_PARAMETER;
 937                 }
 938
 939                 if (!spnego_state->sub_sec_security) {
 940                         DEBUG(1, ("SPNEGO: Did not setup a mech in NEG_TOKEN_INIT\n"));
 941                         spnego_free_data(&spnego);
 942                         return NT_STATUS_INVALID_PARAMETER;
 943                 }
 944
 945                 nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 946                                           out_mem_ctx, ev,
 947                                           spnego.negTokenTarg.responseToken,
 948                                           &unwrapped_out);
 949                 if (NT_STATUS_IS_OK(nt_status) && spnego.negTokenTarg.mechListMIC.length > 0) {
 950                         new_spnego = true;
 951                         nt_status = gensec_check_packet(spnego_state->sub_sec_security,
 952                                                         spnego_state->mech_types.data,
 953                                                         spnego_state->mech_types.length,
 954                                                         spnego_state->mech_types.data,
 955                                                         spnego_state->mech_types.length,
 956                                                         &spnego.negTokenTarg.mechListMIC);
 957                         if (!NT_STATUS_IS_OK(nt_status)) {
 958                                 DEBUG(2,("GENSEC SPNEGO: failed to verify mechListMIC: %s\n",
 959                                         nt_errstr(nt_status)));
 960                         }
 961                 }
 962                 if (NT_STATUS_IS_OK(nt_status) && new_spnego) {
 963                         nt_status = gensec_sign_packet(spnego_state->sub_sec_security,
 964                                                        out_mem_ctx,
 965                                                        spnego_state->mech_types.data,
 966                                                        spnego_state->mech_types.length,
 967                                                        spnego_state->mech_types.data,
 968                                                        spnego_state->mech_types.length,
 969                                                        &mech_list_mic);
 970                         if (!NT_STATUS_IS_OK(nt_status)) {
 971                                 DEBUG(2,("GENSEC SPNEGO: failed to sign mechListMIC: %s\n",
 972                                         nt_errstr(nt_status)));
 973                         }
 974                 }
 975
 976                 nt_status = gensec_spnego_server_negTokenTarg(spnego_state,
 977                                                               out_mem_ctx,
 978                                                               nt_status,
 979                                                               unwrapped_out,
 980                                                               mech_list_mic,
 981                                                               out);
 982
 983                 spnego_free_data(&spnego);
 984
 985                 return nt_status;
 986         }
 987         case SPNEGO_CLIENT_TARG:
 988         {
 989                 NTSTATUS nt_status;
 990                 if (!in.length) {
 991                         return NT_STATUS_INVALID_PARAMETER;
 992                 }
 993
 994                 len = spnego_read_data(gensec_security, in, &spnego);
 995
 996                 if (len == -1) {
 997                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 998                         dump_data(1, in.data, in.length);
 999                         return NT_STATUS_INVALID_PARAMETER;
1000                 }
1001
1002                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
1003                 if (spnego.type != spnego_state->expected_packet) {
1004                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
1005                                   spnego_state->expected_packet));
1006                         dump_data(1, in.data, in.length);
1007                         spnego_free_data(&spnego);
1008                         return NT_STATUS_INVALID_PARAMETER;
1009                 }
1010
1011                 if (spnego.negTokenTarg.negResult == SPNEGO_REJECT) {
1012                         spnego_free_data(&spnego);
1013                         return NT_STATUS_LOGON_FAILURE;
1014                 }
1015
1016                 /* Server didn't like our choice of mech, and chose something else */
1017                 if ((spnego.negTokenTarg.negResult == SPNEGO_ACCEPT_INCOMPLETE) &&
1018                     spnego.negTokenTarg.supportedMech &&
1019                     strcmp(spnego.negTokenTarg.supportedMech, spnego_state->neg_oid) != 0) {
1020                         DEBUG(3,("GENSEC SPNEGO: client preferred mech (%s) not accepted, server wants: %s\n",
1021                                  gensec_get_name_by_oid(gensec_security, spnego.negTokenTarg.supportedMech),
1022                                  gensec_get_name_by_oid(gensec_security, spnego_state->neg_oid)));
1023
1024                         talloc_free(spnego_state->sub_sec_security);
1025                         nt_status = gensec_subcontext_start(spnego_state,
1026                                                             gensec_security,
1027                                                             &spnego_state->sub_sec_security);
1028                         if (!NT_STATUS_IS_OK(nt_status)) {
1029                                 spnego_free_data(&spnego);
1030                                 return nt_status;
1031                         }
1032                         /* select the sub context */
1033                         nt_status = gensec_start_mech_by_oid(spnego_state->sub_sec_security,
1034                                                              spnego.negTokenTarg.supportedMech);
1035                         if (!NT_STATUS_IS_OK(nt_status)) {
1036                                 spnego_free_data(&spnego);
1037                                 return nt_status;
1038                         }
1039
1040                         nt_status = gensec_update_ev(spnego_state->sub_sec_security,
1041                                                   out_mem_ctx, ev,
1042                                                   spnego.negTokenTarg.responseToken,
1043                                                   &unwrapped_out);
1044                         spnego_state->neg_oid = talloc_strdup(spnego_state, spnego.negTokenTarg.supportedMech);
1045                 } else if (spnego_state->no_response_expected) {
1046                         if (spnego.negTokenTarg.negResult != SPNEGO_ACCEPT_COMPLETED) {
1047                                 DEBUG(3,("GENSEC SPNEGO: client GENSEC accepted, but server rejected (bad password?)\n"));
1048                                 nt_status = NT_STATUS_INVALID_PARAMETER;
1049                         } else if (spnego.negTokenTarg.responseToken.length) {
1050                                 DEBUG(2,("GENSEC SPNEGO: client GENSEC accepted, but server continued negotiation!\n"));
1051                                 nt_status = NT_STATUS_INVALID_PARAMETER;
1052                         } else {
1053                                 nt_status = NT_STATUS_OK;
1054                         }
1055                         if (NT_STATUS_IS_OK(nt_status) && spnego.negTokenTarg.mechListMIC.length > 0) {
1056                                 nt_status = gensec_check_packet(spnego_state->sub_sec_security,
1057                                                                 spnego_state->mech_types.data,
1058                                                                 spnego_state->mech_types.length,
1059                                                                 spnego_state->mech_types.data,
1060                                                                 spnego_state->mech_types.length,
1061                                                                 &spnego.negTokenTarg.mechListMIC);
1062                                 if (!NT_STATUS_IS_OK(nt_status)) {
1063                                         DEBUG(2,("GENSEC SPNEGO: failed to verify mechListMIC: %s\n",
1064                                                 nt_errstr(nt_status)));
1065                                 }
1066                         }
1067                 } else {
1068                         bool new_spnego = false;
1069
1070                         nt_status = gensec_update_ev(spnego_state->sub_sec_security,
1071                                                   out_mem_ctx, ev,
1072                                                   spnego.negTokenTarg.responseToken,
1073                                                   &unwrapped_out);
1074
1075                         if (NT_STATUS_IS_OK(nt_status)
1076                             && spnego.negTokenTarg.negResult != SPNEGO_ACCEPT_COMPLETED) {
1077                                 new_spnego = gensec_have_feature(spnego_state->sub_sec_security,
1078                                                                  GENSEC_FEATURE_NEW_SPNEGO);
1079                         }
1080                         if (NT_STATUS_IS_OK(nt_status) && new_spnego) {
1081                                 nt_status = gensec_sign_packet(spnego_state->sub_sec_security,
1082                                                                out_mem_ctx,
1083                                                                spnego_state->mech_types.data,
1084                                                                spnego_state->mech_types.length,
1085                                                                spnego_state->mech_types.data,
1086                                                                spnego_state->mech_types.length,
1087                                                                &mech_list_mic);
1088                                 if (!NT_STATUS_IS_OK(nt_status)) {
1089                                         DEBUG(2,("GENSEC SPNEGO: failed to sign mechListMIC: %s\n",
1090                                                 nt_errstr(nt_status)));
1091                                 }
1092                         }
1093                         if (NT_STATUS_IS_OK(nt_status)) {
1094                                 spnego_state->no_response_expected = true;
1095                         }
1096                 }
1097
1098                 spnego_free_data(&spnego);
1099
1100                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
1101                         && !NT_STATUS_IS_OK(nt_status)) {
1102                         DEBUG(1, ("SPNEGO(%s) login failed: %s\n",
1103                                   spnego_state->sub_sec_security->ops->name,
1104                                   nt_errstr(nt_status)));
1105                         return nt_status;
1106                 }
1107
1108                 if (unwrapped_out.length || mech_list_mic.length) {
1109                         /* compose reply */
1110                         spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
1111                         spnego_out.negTokenTarg.negResult = SPNEGO_NONE_RESULT;
1112                         spnego_out.negTokenTarg.supportedMech = NULL;
1113                         spnego_out.negTokenTarg.responseToken = unwrapped_out;
1114                         spnego_out.negTokenTarg.mechListMIC = mech_list_mic;
1115
1116                         if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
1117                                 DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
1118                                 return NT_STATUS_INVALID_PARAMETER;
1119                         }
1120
1121                         spnego_state->state_position = SPNEGO_CLIENT_TARG;
1122                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
1123                 } else {
1124
1125                         /* all done - server has accepted, and we agree */
1126                         *out = null_data_blob;
1127
1128                         if (spnego.negTokenTarg.negResult != SPNEGO_ACCEPT_COMPLETED) {
1129                                 /* unless of course it did not accept */
1130                                 DEBUG(1,("gensec_update ok but not accepted\n"));
1131                                 nt_status = NT_STATUS_INVALID_PARAMETER;
1132                         }
1133
1134                         spnego_state->state_position = SPNEGO_DONE;
1135                 }
1136
1137                 return nt_status;
1138         }
1139         case SPNEGO_DONE:
1140                 /* We should not be called after we are 'done' */
1141                 return NT_STATUS_INVALID_PARAMETER;
1142         }
1143         return NT_STATUS_INVALID_PARAMETER;
1144 }
1145
1146 static NTSTATUS gensec_spnego_update_in(struct gensec_security *gensec_security,
1147                                         const DATA_BLOB in, DATA_BLOB *full_in)
1148 {
1149         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1150         size_t expected;
1151         NTSTATUS status;
1152         bool ok;
1153
1154         *full_in = data_blob_null;
1155
1156         if (spnego_state->in_needed == 0) {
1157                 size_t size = 0;
1158
1159                 /*
1160                  * try to work out the size of the full
1161                  * input token, it might be fragmented
1162                  */
1163                 status = asn1_peek_full_tag(in,  ASN1_APPLICATION(0), &size);
1164                 if (!NT_STATUS_IS_OK(status) &&
1165                     !NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) {
1166                         status = asn1_peek_full_tag(in, ASN1_CONTEXT(1), &size);
1167                 }
1168
1169                 if (NT_STATUS_IS_OK(status) ||
1170                     NT_STATUS_EQUAL(status, STATUS_MORE_ENTRIES)) {
1171                         spnego_state->in_needed = size;
1172                 } else {
1173                         /*
1174                          * If it is not an asn1 message
1175                          * just call the next layer.
1176                          */
1177                         spnego_state->in_needed = in.length;
1178                 }
1179         }
1180
1181         if (spnego_state->in_needed > UINT16_MAX) {
1182                 /*
1183                  * limit the incoming message to 0xFFFF
1184                  * to avoid DoS attacks.
1185                  */
1186                 return NT_STATUS_INVALID_BUFFER_SIZE;
1187         }
1188
1189         if ((spnego_state->in_needed > 0) && (in.length == 0)) {
1190                 /*
1191                  * If we reach this, we know we got at least
1192                  * part of an asn1 message, getting 0 means
1193                  * the remote peer wants us to spin.
1194                  */
1195                 return NT_STATUS_INVALID_PARAMETER;
1196         }
1197
1198         expected = spnego_state->in_needed - spnego_state->in_frag.length;
1199         if (in.length > expected) {
1200                 /*
1201                  * we got more than expected
1202                  */
1203                 return NT_STATUS_INVALID_PARAMETER;
1204         }
1205
1206         if (in.length == spnego_state->in_needed) {
1207                 /*
1208                  * if the in.length contains the full blob
1209                  * we are done.
1210                  *
1211                  * Note: this implies spnego_state->in_frag.length == 0,
1212                  *       but we do not need to check this explicitly
1213                  *       because we already know that we did not get
1214                  *       more than expected.
1215                  */
1216                 *full_in = in;
1217                 return NT_STATUS_OK;
1218         }
1219
1220         ok = data_blob_append(spnego_state, &spnego_state->in_frag,
1221                               in.data, in.length);
1222         if (!ok) {
1223                 return NT_STATUS_NO_MEMORY;
1224         }
1225
1226         if (spnego_state->in_needed > spnego_state->in_frag.length) {
1227                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
1228         }
1229
1230         *full_in = spnego_state->in_frag;
1231         return NT_STATUS_OK;
1232 }
1233
1234 static NTSTATUS gensec_spnego_update_out(struct gensec_security *gensec_security,
1235                                          TALLOC_CTX *out_mem_ctx,
1236                                          DATA_BLOB *_out)
1237 {
1238         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1239         DATA_BLOB out = data_blob_null;
1240
1241         *_out = data_blob_null;
1242
1243         if (spnego_state->out_frag.length == 0) {
1244                 return spnego_state->out_status;
1245         }
1246
1247         /*
1248          * There is still more data to be delivered
1249          * to the remote peer.
1250          */
1251
1252         if (spnego_state->out_frag.length <= spnego_state->out_max_length) {
1253                 /*
1254                  * Fast path, we can deliver everything
1255                  */
1256
1257                 *_out = spnego_state->out_frag;
1258                 talloc_steal(out_mem_ctx, _out->data);
1259                 spnego_state->out_frag = data_blob_null;
1260                 return spnego_state->out_status;
1261         }
1262
1263         out = spnego_state->out_frag;
1264
1265         /*
1266          * copy the remaining bytes
1267          */
1268         spnego_state->out_frag = data_blob_talloc(spnego_state,
1269                                         out.data + spnego_state->out_max_length,
1270                                         out.length - spnego_state->out_max_length);
1271         if (spnego_state->out_frag.data == NULL) {
1272                 return NT_STATUS_NO_MEMORY;
1273         }
1274
1275         /*
1276          * truncate the buffer
1277          */
1278         data_blob_realloc(spnego_state, &out, spnego_state->out_max_length);
1279
1280         talloc_steal(out_mem_ctx, out.data);
1281         *_out = out;
1282         return NT_STATUS_MORE_PROCESSING_REQUIRED;
1283 }
1284
1285 static NTSTATUS gensec_spnego_update_wrapper(struct gensec_security *gensec_security,
1286                                              TALLOC_CTX *out_mem_ctx,
1287                                              struct tevent_context *ev,
1288                                              const DATA_BLOB in, DATA_BLOB *out)
1289 {
1290         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1291         DATA_BLOB full_in = data_blob_null;
1292         NTSTATUS status;
1293
1294         *out = data_blob_null;
1295
1296         if (spnego_state->out_frag.length > 0) {
1297                 if (in.length > 0) {
1298                         return NT_STATUS_INVALID_PARAMETER;
1299                 }
1300
1301                 return gensec_spnego_update_out(gensec_security,
1302                                                 out_mem_ctx,
1303                                                 out);
1304         }
1305
1306         status = gensec_spnego_update_in(gensec_security,
1307                                          in, &full_in);
1308         if (!NT_STATUS_IS_OK(status)) {
1309                 return status;
1310         }
1311
1312         status = gensec_spnego_update(gensec_security,
1313                                       spnego_state, ev,
1314                                       full_in,
1315                                       &spnego_state->out_frag);
1316         data_blob_free(&spnego_state->in_frag);
1317         spnego_state->in_needed = 0;
1318         if (!NT_STATUS_IS_OK(status) &&
1319             !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
1320                 return status;
1321         }
1322
1323         spnego_state->out_status = status;
1324
1325         return gensec_spnego_update_out(gensec_security,
1326                                         out_mem_ctx,
1327                                         out);
1328 }
1329
1330 static void gensec_spnego_want_feature(struct gensec_security *gensec_security,
1331                                        uint32_t feature)
1332 {
1333         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1334
1335         if (!spnego_state || !spnego_state->sub_sec_security) {
1336                 gensec_security->want_features |= feature;
1337                 return;
1338         }
1339
1340         gensec_want_feature(spnego_state->sub_sec_security,
1341                             feature);
1342 }
1343
1344 static bool gensec_spnego_have_feature(struct gensec_security *gensec_security,
1345                                        uint32_t feature)
1346 {
1347         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1348         if (!spnego_state->sub_sec_security) {
1349                 return false;
1350         }
1351
1352         return gensec_have_feature(spnego_state->sub_sec_security,
1353                                    feature);
1354 }
1355
1356 static NTTIME gensec_spnego_expire_time(struct gensec_security *gensec_security)
1357 {
1358         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1359
1360         if (!spnego_state->sub_sec_security) {
1361                 return GENSEC_EXPIRE_TIME_INFINITY;
1362         }
1363
1364         return gensec_expire_time(spnego_state->sub_sec_security);
1365 }
1366
1367 static const char *gensec_spnego_oids[] = {
1368         GENSEC_OID_SPNEGO,
1369         NULL
1370 };
1371
1372 static const struct gensec_security_ops gensec_spnego_security_ops = {
1373         .name             = "spnego",
1374         .sasl_name        = "GSS-SPNEGO",
1375         .auth_type        = DCERPC_AUTH_TYPE_SPNEGO,
1376         .oid              = gensec_spnego_oids,
1377         .client_start     = gensec_spnego_client_start,
1378         .server_start     = gensec_spnego_server_start,
1379         .update           = gensec_spnego_update_wrapper,
1380         .seal_packet      = gensec_spnego_seal_packet,
1381         .sign_packet      = gensec_spnego_sign_packet,
1382         .sig_size         = gensec_spnego_sig_size,
1383         .max_wrapped_size = gensec_spnego_max_wrapped_size,
1384         .max_input_size   = gensec_spnego_max_input_size,
1385         .check_packet     = gensec_spnego_check_packet,
1386         .unseal_packet    = gensec_spnego_unseal_packet,
1387         .packet_full_request = gensec_spnego_packet_full_request,
1388         .wrap             = gensec_spnego_wrap,
1389         .unwrap           = gensec_spnego_unwrap,
1390         .wrap_packets     = gensec_spnego_wrap_packets,
1391         .unwrap_packets   = gensec_spnego_unwrap_packets,
1392         .session_key      = gensec_spnego_session_key,
1393         .session_info     = gensec_spnego_session_info,
1394         .want_feature     = gensec_spnego_want_feature,
1395         .have_feature     = gensec_spnego_have_feature,
1396         .expire_time      = gensec_spnego_expire_time,
1397         .enabled          = true,
1398         .priority         = GENSEC_SPNEGO
1399 };
1400
1401 _PUBLIC_ NTSTATUS gensec_spnego_init(void)
1402 {
1403         NTSTATUS ret;
1404         ret = gensec_register(&gensec_spnego_security_ops);
1405         if (!NT_STATUS_IS_OK(ret)) {
1406                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1407                         gensec_spnego_security_ops.name));
1408                 return ret;
1409         }
1410
1411         return ret;
1412 }