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 <tevent.h>
  27 #include "lib/util/tevent_ntstatus.h"
  28 #include "../libcli/auth/spnego.h"
  29 #include "librpc/gen_ndr/ndr_dcerpc.h"
  30 #include "auth/credentials/credentials.h"
  31 #include "auth/gensec/gensec.h"
  32 #include "auth/gensec/gensec_internal.h"
  33 #include "param/param.h"
  34 #include "lib/util/asn1.h"
  35 #include "lib/util/base64.h"
  36
  37 #undef strcasecmp
  38
  39 _PUBLIC_ NTSTATUS gensec_spnego_init(TALLOC_CTX *ctx);
  40
  41 enum spnego_state_position {
  42         SPNEGO_SERVER_START,
  43         SPNEGO_CLIENT_START,
  44         SPNEGO_SERVER_TARG,
  45         SPNEGO_CLIENT_TARG,
  46         SPNEGO_FALLBACK,
  47         SPNEGO_DONE
  48 };
  49
  50 struct spnego_state {
  51         enum spnego_message_type expected_packet;
  52         enum spnego_state_position state_position;
  53         struct gensec_security *sub_sec_security;
  54         bool sub_sec_ready;
  55
  56         const char *neg_oid;
  57
  58         DATA_BLOB mech_types;
  59         size_t num_targs;
  60         bool downgraded;
  61         bool mic_requested;
  62         bool needs_mic_sign;
  63         bool needs_mic_check;
  64         bool may_skip_mic_check;
  65         bool done_mic_check;
  66
  67         bool simulate_w2k;
  68
  69         /*
  70          * The following is used to implement
  71          * the update token fragmentation
  72          */
  73         size_t in_needed;
  74         DATA_BLOB in_frag;
  75         size_t out_max_length;
  76         DATA_BLOB out_frag;
  77         NTSTATUS out_status;
  78 };
  79
  80 static void gensec_spnego_update_sub_abort(struct spnego_state *spnego_state)
  81 {
  82         spnego_state->sub_sec_ready = false;
  83         TALLOC_FREE(spnego_state->sub_sec_security);
  84 }
  85
  86 static NTSTATUS gensec_spnego_client_start(struct gensec_security *gensec_security)
  87 {
  88         struct spnego_state *spnego_state;
  89
  90         spnego_state = talloc_zero(gensec_security, struct spnego_state);
  91         if (!spnego_state) {
  92                 return NT_STATUS_NO_MEMORY;
  93         }
  94
  95         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_INIT;
  96         spnego_state->state_position = SPNEGO_CLIENT_START;
  97         spnego_state->sub_sec_security = NULL;
  98         spnego_state->sub_sec_ready = false;
  99         spnego_state->mech_types = data_blob_null;
 100         spnego_state->out_max_length = gensec_max_update_size(gensec_security);
 101         spnego_state->out_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 102
 103         spnego_state->simulate_w2k = gensec_setting_bool(gensec_security->settings,
 104                                                 "spnego", "simulate_w2k", false);
 105
 106         gensec_security->private_data = spnego_state;
 107         return NT_STATUS_OK;
 108 }
 109
 110 static NTSTATUS gensec_spnego_server_start(struct gensec_security *gensec_security)
 111 {
 112         struct spnego_state *spnego_state;
 113
 114         spnego_state = talloc_zero(gensec_security, struct spnego_state);
 115         if (!spnego_state) {
 116                 return NT_STATUS_NO_MEMORY;
 117         }
 118
 119         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_INIT;
 120         spnego_state->state_position = SPNEGO_SERVER_START;
 121         spnego_state->sub_sec_security = NULL;
 122         spnego_state->sub_sec_ready = false;
 123         spnego_state->mech_types = data_blob_null;
 124         spnego_state->out_max_length = gensec_max_update_size(gensec_security);
 125         spnego_state->out_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 126
 127         spnego_state->simulate_w2k = gensec_setting_bool(gensec_security->settings,
 128                                                 "spnego", "simulate_w2k", false);
 129
 130         gensec_security->private_data = spnego_state;
 131         return NT_STATUS_OK;
 132 }
 133
 134 /** Fallback to another GENSEC mechanism, based on magic strings
 135  *
 136  * This is the 'fallback' case, where we don't get SPNEGO, and have to
 137  * try all the other options (and hope they all have a magic string
 138  * they check)
 139 */
 140
 141 static NTSTATUS gensec_spnego_server_try_fallback(struct gensec_security *gensec_security,
 142                                                   struct spnego_state *spnego_state,
 143                                                   TALLOC_CTX *mem_ctx,
 144                                                   const DATA_BLOB in)
 145 {
 146         int i,j;
 147         const struct gensec_security_ops **all_ops;
 148
 149         all_ops = gensec_security_mechs(gensec_security, mem_ctx);
 150
 151         for (i=0; all_ops && all_ops[i]; i++) {
 152                 bool is_spnego;
 153                 NTSTATUS nt_status;
 154
 155                 if (gensec_security != NULL &&
 156                     !gensec_security_ops_enabled(all_ops[i], gensec_security))
 157                 {
 158                         continue;
 159                 }
 160
 161                 if (!all_ops[i]->oid) {
 162                         continue;
 163                 }
 164
 165                 is_spnego = false;
 166                 for (j=0; all_ops[i]->oid[j]; j++) {
 167                         if (strcasecmp(GENSEC_OID_SPNEGO,all_ops[i]->oid[j]) == 0) {
 168                                 is_spnego = true;
 169                         }
 170                 }
 171                 if (is_spnego) {
 172                         continue;
 173                 }
 174
 175                 if (!all_ops[i]->magic) {
 176                         continue;
 177                 }
 178
 179                 nt_status = all_ops[i]->magic(gensec_security, &in);
 180                 if (!NT_STATUS_IS_OK(nt_status)) {
 181                         continue;
 182                 }
 183
 184                 spnego_state->state_position = SPNEGO_FALLBACK;
 185
 186                 nt_status = gensec_subcontext_start(spnego_state,
 187                                                     gensec_security,
 188                                                     &spnego_state->sub_sec_security);
 189
 190                 if (!NT_STATUS_IS_OK(nt_status)) {
 191                         return nt_status;
 192                 }
 193                 /* select the sub context */
 194                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 195                                                      all_ops[i]);
 196                 if (!NT_STATUS_IS_OK(nt_status)) {
 197                         return nt_status;
 198                 }
 199
 200                 return NT_STATUS_OK;
 201         }
 202         DEBUG(1, ("Failed to parse SPNEGO request\n"));
 203         return NT_STATUS_INVALID_PARAMETER;
 204 }
 205
 206 /*
 207    Parse the netTokenInit, either from the client, to the server, or
 208    from the server to the client.
 209 */
 210
 211 static NTSTATUS gensec_spnego_parse_negTokenInit(struct gensec_security *gensec_security,
 212                                                  struct spnego_state *spnego_state,
 213                                                  TALLOC_CTX *out_mem_ctx,
 214                                                  struct tevent_context *ev,
 215                                                  struct spnego_data *spnego_in,
 216                                                  DATA_BLOB *unwrapped_out)
 217 {
 218         int i;
 219         NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 220         const char * const *mechType = NULL;
 221         DATA_BLOB unwrapped_in = data_blob_null;
 222         bool ok;
 223         const struct gensec_security_ops_wrapper *all_sec = NULL;
 224
 225         if (spnego_in->type != SPNEGO_NEG_TOKEN_INIT) {
 226                 return NT_STATUS_INTERNAL_ERROR;
 227         }
 228
 229         mechType = spnego_in->negTokenInit.mechTypes;
 230         unwrapped_in = spnego_in->negTokenInit.mechToken;
 231
 232         all_sec = gensec_security_by_oid_list(gensec_security,
 233                                               out_mem_ctx,
 234                                               mechType,
 235                                               GENSEC_OID_SPNEGO);
 236
 237         ok = spnego_write_mech_types(spnego_state,
 238                                      mechType,
 239                                      &spnego_state->mech_types);
 240         if (!ok) {
 241                 DEBUG(1, ("SPNEGO: Failed to write mechTypes\n"));
 242                 return NT_STATUS_NO_MEMORY;
 243         }
 244
 245         if (spnego_state->state_position == SPNEGO_SERVER_START) {
 246                 uint32_t j;
 247                 for (j=0; mechType && mechType[j]; j++) {
 248                         for (i=0; all_sec && all_sec[i].op; i++) {
 249                                 if (strcmp(mechType[j], all_sec[i].oid) != 0) {
 250                                         continue;
 251                                 }
 252
 253                                 nt_status = gensec_subcontext_start(spnego_state,
 254                                                                     gensec_security,
 255                                                                     &spnego_state->sub_sec_security);
 256                                 if (!NT_STATUS_IS_OK(nt_status)) {
 257                                         return nt_status;
 258                                 }
 259                                 /* select the sub context */
 260                                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 261                                                                      all_sec[i].op);
 262                                 if (!NT_STATUS_IS_OK(nt_status)) {
 263                                         /*
 264                                          * Pretend we never started it
 265                                          */
 266                                         gensec_spnego_update_sub_abort(spnego_state);
 267                                         break;
 268                                 }
 269
 270                                 if (j > 0) {
 271                                         /* no optimistic token */
 272                                         spnego_state->neg_oid = all_sec[i].oid;
 273                                         *unwrapped_out = data_blob_null;
 274                                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 275                                         /*
 276                                          * Indicate the downgrade and request a
 277                                          * mic.
 278                                          */
 279                                         spnego_state->downgraded = true;
 280                                         spnego_state->mic_requested = true;
 281                                         break;
 282                                 }
 283
 284                                 nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 285                                                           out_mem_ctx,
 286                                                           ev,
 287                                                           unwrapped_in,
 288                                                           unwrapped_out);
 289                                 if (NT_STATUS_IS_OK(nt_status)) {
 290                                         spnego_state->sub_sec_ready = true;
 291                                 }
 292                                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER) ||
 293                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_CANT_ACCESS_DOMAIN_INFO)) {
 294
 295                                         DEBUG(1, ("SPNEGO(%s) NEG_TOKEN_INIT failed to parse contents: %s\n",
 296                                                   spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 297
 298                                         /*
 299                                          * Pretend we never started it
 300                                          */
 301                                         gensec_spnego_update_sub_abort(spnego_state);
 302                                         break;
 303                                 }
 304
 305                                 spnego_state->neg_oid = all_sec[i].oid;
 306                                 break;
 307                         }
 308                         if (spnego_state->sub_sec_security) {
 309                                 break;
 310                         }
 311                 }
 312
 313                 if (!spnego_state->sub_sec_security) {
 314                         DEBUG(1, ("SPNEGO: Could not find a suitable mechtype in NEG_TOKEN_INIT\n"));
 315                         return NT_STATUS_INVALID_PARAMETER;
 316                 }
 317         }
 318
 319         /* Having tried any optimistic token from the client (if we
 320          * were the server), if we didn't get anywhere, walk our list
 321          * in our preference order */
 322         unwrapped_in = data_blob_null;
 323
 324         if (!spnego_state->sub_sec_security) {
 325                 for (i=0; all_sec && all_sec[i].op; i++) {
 326                         nt_status = gensec_subcontext_start(spnego_state,
 327                                                             gensec_security,
 328                                                             &spnego_state->sub_sec_security);
 329                         if (!NT_STATUS_IS_OK(nt_status)) {
 330                                 return nt_status;
 331                         }
 332                         /* select the sub context */
 333                         nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 334                                                              all_sec[i].op);
 335                         if (!NT_STATUS_IS_OK(nt_status)) {
 336                                 /*
 337                                  * Pretend we never started it.
 338                                  */
 339                                 gensec_spnego_update_sub_abort(spnego_state);
 340                                 continue;
 341                         }
 342
 343                         spnego_state->neg_oid = all_sec[i].oid;
 344
 345                         /* only get the helping start blob for the first OID */
 346                         nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 347                                                   out_mem_ctx,
 348                                                   ev,
 349                                                   unwrapped_in,
 350                                                   unwrapped_out);
 351                         if (NT_STATUS_IS_OK(nt_status)) {
 352                                 spnego_state->sub_sec_ready = true;
 353                         }
 354
 355                         /* it is likely that a NULL input token will
 356                          * not be liked by most server mechs, but if
 357                          * we are in the client, we want the first
 358                          * update packet to be able to abort the use
 359                          * of this mech */
 360                         if (spnego_state->state_position != SPNEGO_SERVER_START) {
 361                                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER) ||
 362                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_NO_LOGON_SERVERS) ||
 363                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_TIME_DIFFERENCE_AT_DC) ||
 364                                     NT_STATUS_EQUAL(nt_status, NT_STATUS_CANT_ACCESS_DOMAIN_INFO)) {
 365                                         const char *next = NULL;
 366                                         const char *principal = NULL;
 367                                         int dbg_level = DBGLVL_WARNING;
 368
 369                                         if (all_sec[i+1].op != NULL) {
 370                                                 next = all_sec[i+1].op->name;
 371                                                 dbg_level = DBGLVL_NOTICE;
 372                                         }
 373
 374                                         if (gensec_security->target.principal != NULL) {
 375                                                 principal = gensec_security->target.principal;
 376                                         } else if (gensec_security->target.service != NULL &&
 377                                                    gensec_security->target.hostname != NULL)
 378                                         {
 379                                                 principal = talloc_asprintf(spnego_state->sub_sec_security,
 380                                                                             "%s/%s",
 381                                                                             gensec_security->target.service,
 382                                                                             gensec_security->target.hostname);
 383                                         } else {
 384                                                 principal = gensec_security->target.hostname;
 385                                         }
 386
 387                                         DEBUG(dbg_level, ("SPNEGO(%s) creating NEG_TOKEN_INIT for %s failed (next[%s]): %s\n",
 388                                                           spnego_state->sub_sec_security->ops->name,
 389                                                           principal,
 390                                                           next, nt_errstr(nt_status)));
 391
 392                                         /*
 393                                          * Pretend we never started it.
 394                                          */
 395                                         gensec_spnego_update_sub_abort(spnego_state);
 396                                         continue;
 397                                 }
 398                         }
 399
 400                         break;
 401                 }
 402         }
 403
 404         if (spnego_state->sub_sec_security) {
 405                 /* it is likely that a NULL input token will
 406                  * not be liked by most server mechs, but this
 407                  * does the right thing in the CIFS client.
 408                  * just push us along the merry-go-round
 409                  * again, and hope for better luck next
 410                  * time */
 411
 412                 if (NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER)) {
 413                         *unwrapped_out = data_blob_null;
 414                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 415                 }
 416
 417                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_INVALID_PARAMETER)
 418                     && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
 419                     && !NT_STATUS_IS_OK(nt_status)) {
 420                         DEBUG(1, ("SPNEGO(%s) NEG_TOKEN_INIT failed: %s\n",
 421                                   spnego_state->sub_sec_security->ops->name, nt_errstr(nt_status)));
 422
 423                         /* We started the mech correctly, and the
 424                          * input from the other side was valid.
 425                          * Return the error (say bad password, invalid
 426                          * ticket) */
 427                         gensec_spnego_update_sub_abort(spnego_state);
 428                         return nt_status;
 429                 }
 430
 431                 return nt_status; /* OK, INVALID_PARAMETER ore MORE PROCESSING */
 432         }
 433
 434         DEBUG(1, ("SPNEGO: Could not find a suitable mechtype in NEG_TOKEN_INIT\n"));
 435         /* we could re-negotiate here, but it would only work
 436          * if the client or server lied about what it could
 437          * support the first time.  Lets keep this code to
 438          * reality */
 439
 440         return nt_status;
 441 }
 442
 443 /** create a negTokenInit
 444  *
 445  * This is the same packet, no matter if the client or server sends it first, but it is always the first packet
 446 */
 447 static NTSTATUS gensec_spnego_create_negTokenInit(struct gensec_security *gensec_security,
 448                                                   struct spnego_state *spnego_state,
 449                                                   TALLOC_CTX *out_mem_ctx,
 450                                                   struct tevent_context *ev,
 451                                                   DATA_BLOB *out)
 452 {
 453         int i;
 454         NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 455         const char **mechTypes = NULL;
 456         DATA_BLOB unwrapped_out = data_blob_null;
 457         const struct gensec_security_ops_wrapper *all_sec;
 458
 459         mechTypes = gensec_security_oids(gensec_security,
 460                                          out_mem_ctx, GENSEC_OID_SPNEGO);
 461
 462         all_sec = gensec_security_by_oid_list(gensec_security,
 463                                               out_mem_ctx,
 464                                               mechTypes,
 465                                               GENSEC_OID_SPNEGO);
 466         for (i=0; all_sec && all_sec[i].op; i++) {
 467                 struct spnego_data spnego_out;
 468                 const char **send_mech_types;
 469                 bool ok;
 470
 471                 nt_status = gensec_subcontext_start(spnego_state,
 472                                                     gensec_security,
 473                                                     &spnego_state->sub_sec_security);
 474                 if (!NT_STATUS_IS_OK(nt_status)) {
 475                         return nt_status;
 476                 }
 477                 /* select the sub context */
 478                 nt_status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
 479                                                      all_sec[i].op);
 480                 if (!NT_STATUS_IS_OK(nt_status)) {
 481                         gensec_spnego_update_sub_abort(spnego_state);
 482                         continue;
 483                 }
 484
 485                 /* In the client, try and produce the first (optimistic) packet */
 486                 if (spnego_state->state_position == SPNEGO_CLIENT_START) {
 487                         nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 488                                                   out_mem_ctx,
 489                                                   ev,
 490                                                   data_blob_null,
 491                                                   &unwrapped_out);
 492                         if (NT_STATUS_IS_OK(nt_status)) {
 493                                 spnego_state->sub_sec_ready = true;
 494                         }
 495
 496                         if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
 497                             && !NT_STATUS_IS_OK(nt_status)) {
 498                                 const char *next = NULL;
 499                                 const char *principal = NULL;
 500                                 int dbg_level = DBGLVL_WARNING;
 501
 502                                 if (all_sec[i+1].op != NULL) {
 503                                         next = all_sec[i+1].op->name;
 504                                         dbg_level = DBGLVL_NOTICE;
 505                                 }
 506
 507                                 if (gensec_security->target.principal != NULL) {
 508                                         principal = gensec_security->target.principal;
 509                                 } else if (gensec_security->target.service != NULL &&
 510                                            gensec_security->target.hostname != NULL)
 511                                 {
 512                                         principal = talloc_asprintf(spnego_state->sub_sec_security,
 513                                                                     "%s/%s",
 514                                                                     gensec_security->target.service,
 515                                                                     gensec_security->target.hostname);
 516                                 } else {
 517                                         principal = gensec_security->target.hostname;
 518                                 }
 519
 520                                 DEBUG(dbg_level, ("SPNEGO(%s) creating NEG_TOKEN_INIT for %s failed (next[%s]): %s\n",
 521                                           spnego_state->sub_sec_security->ops->name,
 522                                           principal,
 523                                           next, nt_errstr(nt_status)));
 524
 525                                 /*
 526                                  * Pretend we never started it
 527                                  */
 528                                 gensec_spnego_update_sub_abort(spnego_state);
 529                                 continue;
 530                         }
 531                 }
 532
 533                 spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 534
 535                 send_mech_types = gensec_security_oids_from_ops_wrapped(out_mem_ctx,
 536                                                                         &all_sec[i]);
 537
 538                 ok = spnego_write_mech_types(spnego_state,
 539                                              send_mech_types,
 540                                              &spnego_state->mech_types);
 541                 if (!ok) {
 542                         DEBUG(1, ("SPNEGO: Failed to write mechTypes\n"));
 543                         return NT_STATUS_NO_MEMORY;
 544                 }
 545
 546                 /* List the remaining mechs as options */
 547                 spnego_out.negTokenInit.mechTypes = send_mech_types;
 548                 spnego_out.negTokenInit.reqFlags = data_blob_null;
 549                 spnego_out.negTokenInit.reqFlagsPadding = 0;
 550
 551                 if (spnego_state->state_position == SPNEGO_SERVER_START) {
 552                         spnego_out.negTokenInit.mechListMIC
 553                                 = data_blob_string_const(ADS_IGNORE_PRINCIPAL);
 554                 } else {
 555                         spnego_out.negTokenInit.mechListMIC = data_blob_null;
 556                 }
 557
 558                 spnego_out.negTokenInit.mechToken = unwrapped_out;
 559
 560                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 561                         DEBUG(1, ("Failed to write NEG_TOKEN_INIT\n"));
 562                                 return NT_STATUS_INVALID_PARAMETER;
 563                 }
 564
 565                 /* set next state */
 566                 spnego_state->neg_oid = all_sec[i].oid;
 567
 568                 if (spnego_state->state_position == SPNEGO_SERVER_START) {
 569                         spnego_state->state_position = SPNEGO_SERVER_START;
 570                         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_INIT;
 571                 } else {
 572                         spnego_state->state_position = SPNEGO_CLIENT_TARG;
 573                         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 574                 }
 575
 576                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 577         }
 578         gensec_spnego_update_sub_abort(spnego_state);
 579
 580         DEBUG(10, ("Failed to setup SPNEGO negTokenInit request: %s\n", nt_errstr(nt_status)));
 581         return nt_status;
 582 }
 583
 584
 585 /** create a server negTokenTarg
 586  *
 587  * This is the case, where the client is the first one who sends data
 588 */
 589
 590 static NTSTATUS gensec_spnego_server_response(struct spnego_state *spnego_state,
 591                                               TALLOC_CTX *out_mem_ctx,
 592                                               NTSTATUS nt_status,
 593                                               const DATA_BLOB unwrapped_out,
 594                                               DATA_BLOB mech_list_mic,
 595                                               DATA_BLOB *out)
 596 {
 597         struct spnego_data spnego_out;
 598
 599         /* compose reply */
 600         spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
 601         spnego_out.negTokenTarg.responseToken = unwrapped_out;
 602         spnego_out.negTokenTarg.mechListMIC = mech_list_mic;
 603         spnego_out.negTokenTarg.supportedMech = NULL;
 604
 605         if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 606                 spnego_out.negTokenTarg.supportedMech = spnego_state->neg_oid;
 607                 if (spnego_state->mic_requested) {
 608                         spnego_out.negTokenTarg.negResult = SPNEGO_REQUEST_MIC;
 609                         spnego_state->mic_requested = false;
 610                 } else {
 611                         spnego_out.negTokenTarg.negResult = SPNEGO_ACCEPT_INCOMPLETE;
 612                 }
 613                 spnego_state->state_position = SPNEGO_SERVER_TARG;
 614         } else if (NT_STATUS_IS_OK(nt_status)) {
 615                 if (unwrapped_out.data) {
 616                         spnego_out.negTokenTarg.supportedMech = spnego_state->neg_oid;
 617                 }
 618                 spnego_out.negTokenTarg.negResult = SPNEGO_ACCEPT_COMPLETED;
 619                 spnego_state->state_position = SPNEGO_DONE;
 620         } else {
 621                 spnego_out.negTokenTarg.negResult = SPNEGO_REJECT;
 622                 spnego_out.negTokenTarg.mechListMIC = data_blob_null;
 623                 DEBUG(2, ("SPNEGO login failed: %s\n", nt_errstr(nt_status)));
 624                 spnego_state->state_position = SPNEGO_DONE;
 625         }
 626
 627         if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 628                 DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
 629                 return NT_STATUS_INVALID_PARAMETER;
 630         }
 631
 632         spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 633         spnego_state->num_targs++;
 634
 635         return nt_status;
 636 }
 637
 638 static NTSTATUS gensec_spnego_update_client(struct gensec_security *gensec_security,
 639                                             TALLOC_CTX *out_mem_ctx,
 640                                             struct tevent_context *ev,
 641                                             const DATA_BLOB in, DATA_BLOB *out)
 642 {
 643         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
 644         DATA_BLOB mech_list_mic = data_blob_null;
 645         DATA_BLOB unwrapped_out = data_blob_null;
 646         struct spnego_data spnego_out;
 647         struct spnego_data spnego;
 648         ssize_t len;
 649
 650         *out = data_blob_null;
 651
 652         /* and switch into the state machine */
 653
 654         switch (spnego_state->state_position) {
 655         case SPNEGO_CLIENT_START:
 656         {
 657                 /* The server offers a list of mechanisms */
 658
 659                 const char *my_mechs[] = {NULL, NULL};
 660                 NTSTATUS nt_status = NT_STATUS_INVALID_PARAMETER;
 661                 bool ok;
 662                 const char *tp = NULL;
 663
 664                 if (!in.length) {
 665                         /* client to produce negTokenInit */
 666                         return gensec_spnego_create_negTokenInit(gensec_security,
 667                                                                  spnego_state,
 668                                                                  out_mem_ctx,
 669                                                                  ev, out);
 670                 }
 671
 672                 len = spnego_read_data(gensec_security, in, &spnego);
 673
 674                 if (len == -1) {
 675                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 676                         dump_data(1, in.data, in.length);
 677                         return NT_STATUS_INVALID_PARAMETER;
 678                 }
 679
 680                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 681                 if (spnego.type != spnego_state->expected_packet) {
 682                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 683                                   spnego_state->expected_packet));
 684                         dump_data(1, in.data, in.length);
 685                         spnego_free_data(&spnego);
 686                         return NT_STATUS_INVALID_PARAMETER;
 687                 }
 688
 689                 tp = spnego.negTokenInit.targetPrincipal;
 690                 if (tp != NULL && strcmp(tp, ADS_IGNORE_PRINCIPAL) != 0) {
 691                         DEBUG(5, ("Server claims it's principal name is %s\n", tp));
 692                         if (lpcfg_client_use_spnego_principal(gensec_security->settings->lp_ctx)) {
 693                                 gensec_set_target_principal(gensec_security, tp);
 694                         }
 695                 }
 696
 697                 nt_status = gensec_spnego_parse_negTokenInit(gensec_security,
 698                                                              spnego_state,
 699                                                              out_mem_ctx,
 700                                                              ev,
 701                                                              &spnego,
 702                                                              &unwrapped_out);
 703
 704                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(nt_status)) {
 705                         spnego_free_data(&spnego);
 706                         return nt_status;
 707                 }
 708
 709                 my_mechs[0] = spnego_state->neg_oid;
 710                 /* compose reply */
 711                 spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 712                 spnego_out.negTokenInit.mechTypes = my_mechs;
 713                 spnego_out.negTokenInit.reqFlags = data_blob_null;
 714                 spnego_out.negTokenInit.reqFlagsPadding = 0;
 715                 spnego_out.negTokenInit.mechListMIC = data_blob_null;
 716                 spnego_out.negTokenInit.mechToken = unwrapped_out;
 717
 718                 if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
 719                         DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_INIT\n"));
 720                                 return NT_STATUS_INVALID_PARAMETER;
 721                 }
 722
 723                 ok = spnego_write_mech_types(spnego_state,
 724                                              my_mechs,
 725                                              &spnego_state->mech_types);
 726                 if (!ok) {
 727                         DEBUG(1, ("SPNEGO: Failed to write mechTypes\n"));
 728                         return NT_STATUS_NO_MEMORY;
 729                 }
 730
 731                 /* set next state */
 732                 spnego_state->expected_packet = SPNEGO_NEG_TOKEN_TARG;
 733                 spnego_state->state_position = SPNEGO_CLIENT_TARG;
 734
 735                 spnego_free_data(&spnego);
 736                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 737         }
 738
 739         case SPNEGO_CLIENT_TARG:
 740         {
 741                 NTSTATUS nt_status = NT_STATUS_INTERNAL_ERROR;
 742                 const struct spnego_negTokenTarg *ta = NULL;
 743
 744                 if (!in.length) {
 745                         return NT_STATUS_INVALID_PARAMETER;
 746                 }
 747
 748                 len = spnego_read_data(gensec_security, in, &spnego);
 749
 750                 if (len == -1) {
 751                         DEBUG(1, ("Invalid SPNEGO request:\n"));
 752                         dump_data(1, in.data, in.length);
 753                         return NT_STATUS_INVALID_PARAMETER;
 754                 }
 755
 756                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
 757                 if (spnego.type != spnego_state->expected_packet) {
 758                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
 759                                   spnego_state->expected_packet));
 760                         dump_data(1, in.data, in.length);
 761                         spnego_free_data(&spnego);
 762                         return NT_STATUS_INVALID_PARAMETER;
 763                 }
 764                 ta = &spnego.negTokenTarg;
 765
 766                 spnego_state->num_targs++;
 767
 768                 if (ta->negResult == SPNEGO_REJECT) {
 769                         return NT_STATUS_LOGON_FAILURE;
 770                 }
 771
 772                 if (spnego.negTokenTarg.negResult == SPNEGO_REQUEST_MIC) {
 773                         spnego_state->mic_requested = true;
 774                 }
 775
 776                 /* Server didn't like our choice of mech, and chose something else */
 777                 if (((ta->negResult == SPNEGO_ACCEPT_INCOMPLETE) ||
 778                      (ta->negResult == SPNEGO_REQUEST_MIC)) &&
 779                     ta->supportedMech != NULL&&
 780                     strcmp(ta->supportedMech, spnego_state->neg_oid) != 0) {
 781                         DEBUG(3,("GENSEC SPNEGO: client preferred mech (%s) not accepted, server wants: %s\n",
 782                                  gensec_get_name_by_oid(gensec_security, spnego_state->neg_oid),
 783                                  gensec_get_name_by_oid(gensec_security, ta->supportedMech)));
 784                         spnego_state->downgraded = true;
 785                         gensec_spnego_update_sub_abort(spnego_state);
 786                         nt_status = gensec_subcontext_start(spnego_state,
 787                                                             gensec_security,
 788                                                             &spnego_state->sub_sec_security);
 789                         if (!NT_STATUS_IS_OK(nt_status)) {
 790                                 spnego_free_data(&spnego);
 791                                 return nt_status;
 792                         }
 793                         /* select the sub context */
 794                         nt_status = gensec_start_mech_by_oid(spnego_state->sub_sec_security,
 795                                                              ta->supportedMech);
 796                         if (!NT_STATUS_IS_OK(nt_status)) {
 797                                 spnego_free_data(&spnego);
 798                                 return nt_status;
 799                         }
 800
 801                         spnego_state->neg_oid = talloc_strdup(spnego_state,
 802                                                 ta->supportedMech);
 803                         if (spnego_state->neg_oid == NULL) {
 804                                 spnego_free_data(&spnego);
 805                                 return NT_STATUS_NO_MEMORY;
 806                         };
 807                 }
 808
 809                 if (spnego.negTokenTarg.mechListMIC.length > 0) {
 810                         DATA_BLOB *m = &spnego.negTokenTarg.mechListMIC;
 811                         const DATA_BLOB *r = &spnego.negTokenTarg.responseToken;
 812
 813                         /*
 814                          * Windows 2000 has a bug, it repeats the
 815                          * responseToken in the mechListMIC field.
 816                          */
 817                         if (m->length == r->length) {
 818                                 int cmp;
 819
 820                                 cmp = memcmp(m->data, r->data, m->length);
 821                                 if (cmp == 0) {
 822                                         data_blob_free(m);
 823                                 }
 824                         }
 825                 }
 826
 827                 if (spnego.negTokenTarg.mechListMIC.length > 0) {
 828                         if (spnego_state->sub_sec_ready) {
 829                                 spnego_state->needs_mic_check = true;
 830                         }
 831                 }
 832
 833                 if (spnego_state->needs_mic_check) {
 834                         if (spnego.negTokenTarg.responseToken.length != 0) {
 835                                 DEBUG(1, ("SPNEGO: Did not setup a mech in NEG_TOKEN_INIT\n"));
 836                                 spnego_free_data(&spnego);
 837                                 return NT_STATUS_INVALID_PARAMETER;
 838                         }
 839
 840                         if (spnego.negTokenTarg.mechListMIC.length == 0
 841                             && spnego_state->may_skip_mic_check) {
 842                                 /*
 843                                  * In this case we don't require
 844                                  * a mechListMIC from the server.
 845                                  *
 846                                  * This works around bugs in the Azure
 847                                  * and Apple spnego implementations.
 848                                  *
 849                                  * See
 850                                  * https://bugzilla.samba.org/show_bug.cgi?id=11994
 851                                  */
 852                                 spnego_state->needs_mic_check = false;
 853                                 nt_status = NT_STATUS_OK;
 854                                 goto client_response;
 855                         }
 856
 857                         nt_status = gensec_check_packet(spnego_state->sub_sec_security,
 858                                                         spnego_state->mech_types.data,
 859                                                         spnego_state->mech_types.length,
 860                                                         spnego_state->mech_types.data,
 861                                                         spnego_state->mech_types.length,
 862                                                         &spnego.negTokenTarg.mechListMIC);
 863                         if (!NT_STATUS_IS_OK(nt_status)) {
 864                                 DEBUG(2,("GENSEC SPNEGO: failed to verify mechListMIC: %s\n",
 865                                         nt_errstr(nt_status)));
 866                                 spnego_free_data(&spnego);
 867                                 return nt_status;
 868                         }
 869                         spnego_state->needs_mic_check = false;
 870                         spnego_state->done_mic_check = true;
 871                         goto client_response;
 872                 }
 873
 874                 if (!spnego_state->sub_sec_ready) {
 875                         nt_status = gensec_update_ev(spnego_state->sub_sec_security,
 876                                                   out_mem_ctx, ev,
 877                                                   spnego.negTokenTarg.responseToken,
 878                                                   &unwrapped_out);
 879                         if (NT_STATUS_IS_OK(nt_status)) {
 880                                 spnego_state->sub_sec_ready = true;
 881                         }
 882                         if (!NT_STATUS_IS_OK(nt_status)) {
 883                                 goto client_response;
 884                         }
 885                 } else {
 886                         nt_status = NT_STATUS_OK;
 887                 }
 888
 889                 if (!spnego_state->done_mic_check) {
 890                         bool have_sign = true;
 891                         bool new_spnego = false;
 892
 893                         have_sign = gensec_have_feature(spnego_state->sub_sec_security,
 894                                                         GENSEC_FEATURE_SIGN);
 895                         if (spnego_state->simulate_w2k) {
 896                                 have_sign = false;
 897                         }
 898                         new_spnego = gensec_have_feature(spnego_state->sub_sec_security,
 899                                                          GENSEC_FEATURE_NEW_SPNEGO);
 900
 901                         switch (spnego.negTokenTarg.negResult) {
 902                         case SPNEGO_ACCEPT_COMPLETED:
 903                         case SPNEGO_NONE_RESULT:
 904                                 if (spnego_state->num_targs == 1) {
 905                                         /*
 906                                          * the first exchange doesn't require
 907                                          * verification
 908                                          */
 909                                         new_spnego = false;
 910                                 }
 911
 912                                 break;
 913
 914                         case SPNEGO_ACCEPT_INCOMPLETE:
 915                                 if (spnego.negTokenTarg.mechListMIC.length > 0) {
 916                                         new_spnego = true;
 917                                         break;
 918                                 }
 919
 920                                 if (spnego_state->downgraded) {
 921                                         /*
 922                                          * A downgrade should be protected if
 923                                          * supported
 924                                          */
 925                                         break;
 926                                 }
 927
 928                                 /*
 929                                  * The caller may just asked for
 930                                  * GENSEC_FEATURE_SESSION_KEY, this
 931                                  * is only reflected in the want_features.
 932                                  *
 933                                  * As it will imply
 934                                  * gensec_have_features(GENSEC_FEATURE_SIGN)
 935                                  * to return true.
 936                                  */
 937                                 if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 938                                         break;
 939                                 }
 940                                 if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 941                                         break;
 942                                 }
 943                                 /*
 944                                  * Here we're sure our preferred mech was
 945                                  * selected by the server and our caller doesn't
 946                                  * need GENSEC_FEATURE_SIGN nor
 947                                  * GENSEC_FEATURE_SEAL support.
 948                                  *
 949                                  * In this case we don't require
 950                                  * a mechListMIC from the server.
 951                                  *
 952                                  * This works around bugs in the Azure
 953                                  * and Apple spnego implementations.
 954                                  *
 955                                  * See
 956                                  * https://bugzilla.samba.org/show_bug.cgi?id=11994
 957                                  */
 958                                 spnego_state->may_skip_mic_check = true;
 959                                 break;
 960
 961                         case SPNEGO_REQUEST_MIC:
 962                                 if (spnego.negTokenTarg.mechListMIC.length > 0) {
 963                                         new_spnego = true;
 964                                 }
 965                                 break;
 966                         default:
 967                                 break;
 968                         }
 969
 970                         if (spnego_state->mic_requested) {
 971                                 if (have_sign) {
 972                                         new_spnego = true;
 973                                 }
 974                         }
 975
 976                         if (have_sign && new_spnego) {
 977                                 spnego_state->needs_mic_check = true;
 978                                 spnego_state->needs_mic_sign = true;
 979                         }
 980                 }
 981
 982                 if (spnego.negTokenTarg.mechListMIC.length > 0) {
 983                         nt_status = gensec_check_packet(spnego_state->sub_sec_security,
 984                                                         spnego_state->mech_types.data,
 985                                                         spnego_state->mech_types.length,
 986                                                         spnego_state->mech_types.data,
 987                                                         spnego_state->mech_types.length,
 988                                                         &spnego.negTokenTarg.mechListMIC);
 989                         if (!NT_STATUS_IS_OK(nt_status)) {
 990                                 DEBUG(2,("GENSEC SPNEGO: failed to verify mechListMIC: %s\n",
 991                                         nt_errstr(nt_status)));
 992                                 spnego_free_data(&spnego);
 993                                 return nt_status;
 994                         }
 995                         spnego_state->needs_mic_check = false;
 996                         spnego_state->done_mic_check = true;
 997                 }
 998
 999                 if (spnego_state->needs_mic_sign) {
1000                         nt_status = gensec_sign_packet(spnego_state->sub_sec_security,
1001                                                        out_mem_ctx,
1002                                                        spnego_state->mech_types.data,
1003                                                        spnego_state->mech_types.length,
1004                                                        spnego_state->mech_types.data,
1005                                                        spnego_state->mech_types.length,
1006                                                        &mech_list_mic);
1007                         if (!NT_STATUS_IS_OK(nt_status)) {
1008                                 DEBUG(2,("GENSEC SPNEGO: failed to sign mechListMIC: %s\n",
1009                                         nt_errstr(nt_status)));
1010                                 spnego_free_data(&spnego);
1011                                 return nt_status;
1012                         }
1013                         spnego_state->needs_mic_sign = false;
1014                 }
1015
1016                 if (spnego_state->needs_mic_check) {
1017                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
1018                 }
1019
1020  client_response:
1021                 spnego_free_data(&spnego);
1022
1023                 if (!NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
1024                         && !NT_STATUS_IS_OK(nt_status)) {
1025                         DEBUG(1, ("SPNEGO(%s) login failed: %s\n",
1026                                   spnego_state->sub_sec_security->ops->name,
1027                                   nt_errstr(nt_status)));
1028                         return nt_status;
1029                 }
1030
1031                 if (unwrapped_out.length || mech_list_mic.length) {
1032                         /* compose reply */
1033                         spnego_out.type = SPNEGO_NEG_TOKEN_TARG;
1034                         spnego_out.negTokenTarg.negResult = SPNEGO_NONE_RESULT;
1035                         spnego_out.negTokenTarg.supportedMech = NULL;
1036                         spnego_out.negTokenTarg.responseToken = unwrapped_out;
1037                         spnego_out.negTokenTarg.mechListMIC = mech_list_mic;
1038
1039                         if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
1040                                 DEBUG(1, ("Failed to write SPNEGO reply to NEG_TOKEN_TARG\n"));
1041                                 return NT_STATUS_INVALID_PARAMETER;
1042                         }
1043
1044                         spnego_state->num_targs++;
1045                         spnego_state->state_position = SPNEGO_CLIENT_TARG;
1046                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
1047                 } else {
1048
1049                         /* all done - server has accepted, and we agree */
1050                         *out = data_blob_null;
1051
1052                         if (ta->negResult != SPNEGO_ACCEPT_COMPLETED) {
1053                                 /* unless of course it did not accept */
1054                                 DEBUG(1,("gensec_update ok but not accepted\n"));
1055                                 nt_status = NT_STATUS_INVALID_PARAMETER;
1056                         }
1057
1058                         spnego_state->state_position = SPNEGO_DONE;
1059                 }
1060
1061                 return nt_status;
1062         }
1063
1064         default:
1065                 break;
1066         }
1067
1068         smb_panic(__location__);
1069         return NT_STATUS_INTERNAL_ERROR;
1070 }
1071
1072 static NTSTATUS gensec_spnego_update_server(struct gensec_security *gensec_security,
1073                                             TALLOC_CTX *out_mem_ctx,
1074                                             struct tevent_context *ev,
1075                                             const DATA_BLOB in, DATA_BLOB *out)
1076 {
1077         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1078         DATA_BLOB mech_list_mic = data_blob_null;
1079         DATA_BLOB unwrapped_out = data_blob_null;
1080         struct spnego_data spnego;
1081         ssize_t len;
1082
1083         /* and switch into the state machine */
1084
1085         switch (spnego_state->state_position) {
1086         case SPNEGO_SERVER_START:
1087         {
1088                 NTSTATUS nt_status;
1089
1090                 if (in.length == 0) {
1091                         return gensec_spnego_create_negTokenInit(gensec_security,
1092                                                                  spnego_state,
1093                                                                  out_mem_ctx,
1094                                                                  ev, out);
1095                 }
1096
1097                 len = spnego_read_data(gensec_security, in, &spnego);
1098                 if (len == -1) {
1099                         /*
1100                          * This is the 'fallback' case, where we don't get
1101                          * SPNEGO, and have to try all the other options (and
1102                          * hope they all have a magic string they check)
1103                          */
1104                         nt_status = gensec_spnego_server_try_fallback(gensec_security,
1105                                                                       spnego_state,
1106                                                                       out_mem_ctx,
1107                                                                       in);
1108                         if (!NT_STATUS_IS_OK(nt_status)) {
1109                                 return nt_status;
1110                         }
1111
1112                         return gensec_update_ev(spnego_state->sub_sec_security,
1113                                                 out_mem_ctx, ev,
1114                                                 in, out);
1115                 }
1116                 /* client sent NegTargetInit, we send NegTokenTarg */
1117
1118                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
1119                 if (spnego.type != spnego_state->expected_packet) {
1120                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
1121                                   spnego_state->expected_packet));
1122                         dump_data(1, in.data, in.length);
1123                         spnego_free_data(&spnego);
1124                         return NT_STATUS_INVALID_PARAMETER;
1125                 }
1126
1127                 nt_status = gensec_spnego_parse_negTokenInit(gensec_security,
1128                                                              spnego_state,
1129                                                              out_mem_ctx,
1130                                                              ev,
1131                                                              &spnego,
1132                                                              &unwrapped_out);
1133
1134                 if (spnego_state->simulate_w2k) {
1135                         /*
1136                          * Windows 2000 returns the unwrapped token
1137                          * also in the mech_list_mic field.
1138                          *
1139                          * In order to verify our client code,
1140                          * we need a way to have a server with this
1141                          * broken behaviour
1142                          */
1143                         mech_list_mic = unwrapped_out;
1144                 }
1145
1146                 nt_status = gensec_spnego_server_response(spnego_state,
1147                                                           out_mem_ctx,
1148                                                           nt_status,
1149                                                           unwrapped_out,
1150                                                           mech_list_mic,
1151                                                           out);
1152
1153                 spnego_free_data(&spnego);
1154
1155                 return nt_status;
1156         }
1157
1158         case SPNEGO_SERVER_TARG:
1159         {
1160                 NTSTATUS nt_status;
1161                 bool have_sign = true;
1162                 bool new_spnego = false;
1163
1164                 if (!in.length) {
1165                         return NT_STATUS_INVALID_PARAMETER;
1166                 }
1167
1168                 len = spnego_read_data(gensec_security, in, &spnego);
1169
1170                 if (len == -1) {
1171                         DEBUG(1, ("Invalid SPNEGO request:\n"));
1172                         dump_data(1, in.data, in.length);
1173                         return NT_STATUS_INVALID_PARAMETER;
1174                 }
1175
1176                 /* OK, so it's real SPNEGO, check the packet's the one we expect */
1177                 if (spnego.type != spnego_state->expected_packet) {
1178                         DEBUG(1, ("Invalid SPNEGO request: %d, expected %d\n", spnego.type,
1179                                   spnego_state->expected_packet));
1180                         dump_data(1, in.data, in.length);
1181                         spnego_free_data(&spnego);
1182                         return NT_STATUS_INVALID_PARAMETER;
1183                 }
1184
1185                 spnego_state->num_targs++;
1186
1187                 if (!spnego_state->sub_sec_security) {
1188                         DEBUG(1, ("SPNEGO: Did not setup a mech in NEG_TOKEN_INIT\n"));
1189                         spnego_free_data(&spnego);
1190                         return NT_STATUS_INVALID_PARAMETER;
1191                 }
1192
1193                 if (spnego_state->needs_mic_check) {
1194                         if (spnego.negTokenTarg.responseToken.length != 0) {
1195                                 DEBUG(1, ("SPNEGO: Did not setup a mech in NEG_TOKEN_INIT\n"));
1196                                 spnego_free_data(&spnego);
1197                                 return NT_STATUS_INVALID_PARAMETER;
1198                         }
1199
1200                         nt_status = gensec_check_packet(spnego_state->sub_sec_security,
1201                                                         spnego_state->mech_types.data,
1202                                                         spnego_state->mech_types.length,
1203                                                         spnego_state->mech_types.data,
1204                                                         spnego_state->mech_types.length,
1205                                                         &spnego.negTokenTarg.mechListMIC);
1206                         if (NT_STATUS_IS_OK(nt_status)) {
1207                                 spnego_state->needs_mic_check = false;
1208                                 spnego_state->done_mic_check = true;
1209                         } else {
1210                                 DEBUG(2,("GENSEC SPNEGO: failed to verify mechListMIC: %s\n",
1211                                         nt_errstr(nt_status)));
1212                         }
1213                         goto server_response;
1214                 }
1215
1216                 if (!spnego_state->sub_sec_ready) {
1217                         nt_status = gensec_update_ev(spnego_state->sub_sec_security,
1218                                                      out_mem_ctx, ev,
1219                                                      spnego.negTokenTarg.responseToken,
1220                                                      &unwrapped_out);
1221                         if (NT_STATUS_IS_OK(nt_status)) {
1222                                 spnego_state->sub_sec_ready = true;
1223                         }
1224                         if (!NT_STATUS_IS_OK(nt_status)) {
1225                                 goto server_response;
1226                         }
1227                 } else {
1228                         nt_status = NT_STATUS_OK;
1229                 }
1230
1231                 have_sign = gensec_have_feature(spnego_state->sub_sec_security,
1232                                                 GENSEC_FEATURE_SIGN);
1233                 if (spnego_state->simulate_w2k) {
1234                         have_sign = false;
1235                 }
1236                 new_spnego = gensec_have_feature(spnego_state->sub_sec_security,
1237                                                  GENSEC_FEATURE_NEW_SPNEGO);
1238                 if (spnego.negTokenTarg.mechListMIC.length > 0) {
1239                         new_spnego = true;
1240                 }
1241
1242                 if (have_sign && new_spnego) {
1243                         spnego_state->needs_mic_check = true;
1244                         spnego_state->needs_mic_sign = true;
1245                 }
1246
1247                 if (have_sign && spnego.negTokenTarg.mechListMIC.length > 0) {
1248                         nt_status = gensec_check_packet(spnego_state->sub_sec_security,
1249                                                         spnego_state->mech_types.data,
1250                                                         spnego_state->mech_types.length,
1251                                                         spnego_state->mech_types.data,
1252                                                         spnego_state->mech_types.length,
1253                                                         &spnego.negTokenTarg.mechListMIC);
1254                         if (!NT_STATUS_IS_OK(nt_status)) {
1255                                 DEBUG(2,("GENSEC SPNEGO: failed to verify mechListMIC: %s\n",
1256                                         nt_errstr(nt_status)));
1257                                 goto server_response;
1258                         }
1259
1260                         spnego_state->needs_mic_check = false;
1261                         spnego_state->done_mic_check = true;
1262                 }
1263
1264                 if (spnego_state->needs_mic_sign) {
1265                         nt_status = gensec_sign_packet(spnego_state->sub_sec_security,
1266                                                        out_mem_ctx,
1267                                                        spnego_state->mech_types.data,
1268                                                        spnego_state->mech_types.length,
1269                                                        spnego_state->mech_types.data,
1270                                                        spnego_state->mech_types.length,
1271                                                        &mech_list_mic);
1272                         if (!NT_STATUS_IS_OK(nt_status)) {
1273                                 DEBUG(2,("GENSEC SPNEGO: failed to sign mechListMIC: %s\n",
1274                                         nt_errstr(nt_status)));
1275                                 goto server_response;
1276                         }
1277                         spnego_state->needs_mic_sign = false;
1278                 }
1279
1280                 if (spnego_state->needs_mic_check) {
1281                         nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
1282                 }
1283
1284  server_response:
1285                 nt_status = gensec_spnego_server_response(spnego_state,
1286                                                           out_mem_ctx,
1287                                                           nt_status,
1288                                                           unwrapped_out,
1289                                                           mech_list_mic,
1290                                                           out);
1291
1292                 spnego_free_data(&spnego);
1293
1294                 return nt_status;
1295         }
1296
1297         default:
1298                 break;
1299         }
1300
1301         smb_panic(__location__);
1302         return NT_STATUS_INTERNAL_ERROR;
1303 }
1304
1305 struct gensec_spnego_update_state {
1306         struct gensec_security *gensec;
1307         struct spnego_state *spnego;
1308         DATA_BLOB full_in;
1309         NTSTATUS status;
1310         DATA_BLOB out;
1311 };
1312
1313 static void gensec_spnego_update_cleanup(struct tevent_req *req,
1314                                          enum tevent_req_state req_state)
1315 {
1316         struct gensec_spnego_update_state *state =
1317                 tevent_req_data(req,
1318                 struct gensec_spnego_update_state);
1319
1320         switch (req_state) {
1321         case TEVENT_REQ_USER_ERROR:
1322         case TEVENT_REQ_TIMED_OUT:
1323         case TEVENT_REQ_NO_MEMORY:
1324                 /*
1325                  * A fatal error, further updates are not allowed.
1326                  */
1327                 state->spnego->state_position = SPNEGO_DONE;
1328                 break;
1329         default:
1330                 break;
1331         }
1332 }
1333
1334 static NTSTATUS gensec_spnego_update_in(struct gensec_security *gensec_security,
1335                                         const DATA_BLOB in, TALLOC_CTX *mem_ctx,
1336                                         DATA_BLOB *full_in);
1337 static NTSTATUS gensec_spnego_update_out(struct gensec_security *gensec_security,
1338                                          TALLOC_CTX *out_mem_ctx,
1339                                          DATA_BLOB *_out);
1340
1341 static struct tevent_req *gensec_spnego_update_send(TALLOC_CTX *mem_ctx,
1342                                                     struct tevent_context *ev,
1343                                                     struct gensec_security *gensec_security,
1344                                                     const DATA_BLOB in)
1345 {
1346         struct spnego_state *spnego_state =
1347                 talloc_get_type_abort(gensec_security->private_data,
1348                 struct spnego_state);
1349         struct tevent_req *req = NULL;
1350         struct gensec_spnego_update_state *state = NULL;
1351         NTSTATUS status;
1352
1353         req = tevent_req_create(mem_ctx, &state,
1354                                 struct gensec_spnego_update_state);
1355         if (req == NULL) {
1356                 return NULL;
1357         }
1358         state->gensec = gensec_security;
1359         state->spnego = spnego_state;
1360         tevent_req_set_cleanup_fn(req, gensec_spnego_update_cleanup);
1361
1362         if (spnego_state->out_frag.length > 0) {
1363                 if (in.length > 0) {
1364                         tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
1365                         return tevent_req_post(req, ev);
1366                 }
1367
1368                 status = gensec_spnego_update_out(gensec_security,
1369                                                   state, &state->out);
1370                 state->status = status;
1371                 if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
1372                         tevent_req_done(req);
1373                         return tevent_req_post(req, ev);
1374                 }
1375                 if (tevent_req_nterror(req, status)) {
1376                         return tevent_req_post(req, ev);
1377                 }
1378
1379                 tevent_req_done(req);
1380                 return tevent_req_post(req, ev);
1381         }
1382
1383         status = gensec_spnego_update_in(gensec_security, in,
1384                                          state, &state->full_in);
1385         state->status = status;
1386         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
1387                 tevent_req_done(req);
1388                 return tevent_req_post(req, ev);
1389         }
1390         if (tevent_req_nterror(req, status)) {
1391                 return tevent_req_post(req, ev);
1392         }
1393
1394         /* and switch into the state machine */
1395
1396         switch (spnego_state->state_position) {
1397         case SPNEGO_FALLBACK:
1398                 status = gensec_update_ev(spnego_state->sub_sec_security,
1399                                           state, ev,
1400                                           state->full_in,
1401                                           &spnego_state->out_frag);
1402                 break;
1403
1404         case SPNEGO_CLIENT_START:
1405         case SPNEGO_CLIENT_TARG:
1406                 status = gensec_spnego_update_client(gensec_security,
1407                                                      state, ev,
1408                                                      state->full_in,
1409                                                      &spnego_state->out_frag);
1410                 break;
1411
1412         case SPNEGO_SERVER_START:
1413         case SPNEGO_SERVER_TARG:
1414                 status = gensec_spnego_update_server(gensec_security,
1415                                                      state, ev,
1416                                                      state->full_in,
1417                                                      &spnego_state->out_frag);
1418                 break;
1419
1420         default:
1421                 smb_panic(__location__);
1422                 return NULL;
1423         }
1424
1425         if (NT_STATUS_IS_OK(status)) {
1426                 bool reset_full = true;
1427
1428                 reset_full = !spnego_state->done_mic_check;
1429
1430                 status = gensec_may_reset_crypto(spnego_state->sub_sec_security,
1431                                                  reset_full);
1432         }
1433         if (!NT_STATUS_IS_OK(status) &&
1434             !NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
1435                 tevent_req_nterror(req, status);
1436                 return tevent_req_post(req, ev);
1437         }
1438
1439         spnego_state->out_status = status;
1440
1441         status = gensec_spnego_update_out(gensec_security,
1442                                           state, &state->out);
1443         state->status = status;
1444         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
1445                 tevent_req_done(req);
1446                 return tevent_req_post(req, ev);
1447         }
1448         if (tevent_req_nterror(req, status)) {
1449                 return tevent_req_post(req, ev);
1450         }
1451
1452         tevent_req_done(req);
1453         return tevent_req_post(req, ev);
1454 }
1455
1456 static NTSTATUS gensec_spnego_update_in(struct gensec_security *gensec_security,
1457                                         const DATA_BLOB in, TALLOC_CTX *mem_ctx,
1458                                         DATA_BLOB *full_in)
1459 {
1460         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1461         size_t expected;
1462         bool ok;
1463
1464         *full_in = data_blob_null;
1465
1466         switch (spnego_state->state_position) {
1467         case SPNEGO_FALLBACK:
1468                 *full_in = in;
1469                 spnego_state->in_needed = 0;
1470                 return NT_STATUS_OK;
1471
1472         case SPNEGO_CLIENT_START:
1473         case SPNEGO_CLIENT_TARG:
1474         case SPNEGO_SERVER_START:
1475         case SPNEGO_SERVER_TARG:
1476                 break;
1477
1478         case SPNEGO_DONE:
1479         default:
1480                 return NT_STATUS_INVALID_PARAMETER;
1481         }
1482
1483         if (spnego_state->in_needed == 0) {
1484                 size_t size = 0;
1485                 int ret;
1486
1487                 /*
1488                  * try to work out the size of the full
1489                  * input token, it might be fragmented
1490                  */
1491                 ret = asn1_peek_full_tag(in,  ASN1_APPLICATION(0), &size);
1492                 if ((ret != 0) && (ret != EAGAIN)) {
1493                         ret = asn1_peek_full_tag(in, ASN1_CONTEXT(1), &size);
1494                 }
1495
1496                 if ((ret == 0) || (ret == EAGAIN)) {
1497                         spnego_state->in_needed = size;
1498                 } else {
1499                         /*
1500                          * If it is not an asn1 message
1501                          * just call the next layer.
1502                          */
1503                         spnego_state->in_needed = in.length;
1504                 }
1505         }
1506
1507         if (spnego_state->in_needed > UINT16_MAX) {
1508                 /*
1509                  * limit the incoming message to 0xFFFF
1510                  * to avoid DoS attacks.
1511                  */
1512                 return NT_STATUS_INVALID_BUFFER_SIZE;
1513         }
1514
1515         if ((spnego_state->in_needed > 0) && (in.length == 0)) {
1516                 /*
1517                  * If we reach this, we know we got at least
1518                  * part of an asn1 message, getting 0 means
1519                  * the remote peer wants us to spin.
1520                  */
1521                 return NT_STATUS_INVALID_PARAMETER;
1522         }
1523
1524         expected = spnego_state->in_needed - spnego_state->in_frag.length;
1525         if (in.length > expected) {
1526                 /*
1527                  * we got more than expected
1528                  */
1529                 return NT_STATUS_INVALID_PARAMETER;
1530         }
1531
1532         if (in.length == spnego_state->in_needed) {
1533                 /*
1534                  * if the in.length contains the full blob
1535                  * we are done.
1536                  *
1537                  * Note: this implies spnego_state->in_frag.length == 0,
1538                  *       but we do not need to check this explicitly
1539                  *       because we already know that we did not get
1540                  *       more than expected.
1541                  */
1542                 *full_in = in;
1543                 spnego_state->in_needed = 0;
1544                 return NT_STATUS_OK;
1545         }
1546
1547         ok = data_blob_append(spnego_state, &spnego_state->in_frag,
1548                               in.data, in.length);
1549         if (!ok) {
1550                 return NT_STATUS_NO_MEMORY;
1551         }
1552
1553         if (spnego_state->in_needed > spnego_state->in_frag.length) {
1554                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
1555         }
1556
1557         *full_in = spnego_state->in_frag;
1558         talloc_steal(mem_ctx, full_in->data);
1559         spnego_state->in_frag = data_blob_null;
1560         spnego_state->in_needed = 0;
1561         return NT_STATUS_OK;
1562 }
1563
1564 static NTSTATUS gensec_spnego_update_out(struct gensec_security *gensec_security,
1565                                          TALLOC_CTX *out_mem_ctx,
1566                                          DATA_BLOB *_out)
1567 {
1568         struct spnego_state *spnego_state = (struct spnego_state *)gensec_security->private_data;
1569         DATA_BLOB out = data_blob_null;
1570         bool ok;
1571
1572         *_out = data_blob_null;
1573
1574         if (spnego_state->out_frag.length <= spnego_state->out_max_length) {
1575                 /*
1576                  * Fast path, we can deliver everything
1577                  */
1578
1579                 *_out = spnego_state->out_frag;
1580                 if (spnego_state->out_frag.length > 0) {
1581                         talloc_steal(out_mem_ctx, _out->data);
1582                         spnego_state->out_frag = data_blob_null;
1583                 }
1584
1585                 if (!NT_STATUS_IS_OK(spnego_state->out_status)) {
1586                         return spnego_state->out_status;
1587                 }
1588
1589                 /*
1590                  * We're completely done, further updates are not allowed.
1591                  */
1592                 spnego_state->state_position = SPNEGO_DONE;
1593                 return gensec_child_ready(gensec_security,
1594                                           spnego_state->sub_sec_security);
1595         }
1596
1597         out = spnego_state->out_frag;
1598
1599         /*
1600          * copy the remaining bytes
1601          */
1602         spnego_state->out_frag = data_blob_talloc(spnego_state,
1603                                         out.data + spnego_state->out_max_length,
1604                                         out.length - spnego_state->out_max_length);
1605         if (spnego_state->out_frag.data == NULL) {
1606                 return NT_STATUS_NO_MEMORY;
1607         }
1608
1609         /*
1610          * truncate the buffer
1611          */
1612         ok = data_blob_realloc(spnego_state, &out,
1613                                spnego_state->out_max_length);
1614         if (!ok) {
1615                 return NT_STATUS_NO_MEMORY;
1616         }
1617
1618         talloc_steal(out_mem_ctx, out.data);
1619         *_out = out;
1620         return NT_STATUS_MORE_PROCESSING_REQUIRED;
1621 }
1622
1623 static NTSTATUS gensec_spnego_update_recv(struct tevent_req *req,
1624                                           TALLOC_CTX *out_mem_ctx,
1625                                           DATA_BLOB *out)
1626 {
1627         struct gensec_spnego_update_state *state =
1628                 tevent_req_data(req,
1629                 struct gensec_spnego_update_state);
1630         NTSTATUS status;
1631
1632         *out = data_blob_null;
1633
1634         if (tevent_req_is_nterror(req, &status)) {
1635                 tevent_req_received(req);
1636                 return status;
1637         }
1638
1639         *out = state->out;
1640         talloc_steal(out_mem_ctx, state->out.data);
1641         status = state->status;
1642         tevent_req_received(req);
1643         return status;
1644 }
1645
1646 static const char *gensec_spnego_oids[] = {
1647         GENSEC_OID_SPNEGO,
1648         NULL
1649 };
1650
1651 static const struct gensec_security_ops gensec_spnego_security_ops = {
1652         .name             = "spnego",
1653         .sasl_name        = "GSS-SPNEGO",
1654         .auth_type        = DCERPC_AUTH_TYPE_SPNEGO,
1655         .oid              = gensec_spnego_oids,
1656         .client_start     = gensec_spnego_client_start,
1657         .server_start     = gensec_spnego_server_start,
1658         .update_send      = gensec_spnego_update_send,
1659         .update_recv      = gensec_spnego_update_recv,
1660         .seal_packet      = gensec_child_seal_packet,
1661         .sign_packet      = gensec_child_sign_packet,
1662         .sig_size         = gensec_child_sig_size,
1663         .max_wrapped_size = gensec_child_max_wrapped_size,
1664         .max_input_size   = gensec_child_max_input_size,
1665         .check_packet     = gensec_child_check_packet,
1666         .unseal_packet    = gensec_child_unseal_packet,
1667         .wrap             = gensec_child_wrap,
1668         .unwrap           = gensec_child_unwrap,
1669         .session_key      = gensec_child_session_key,
1670         .session_info     = gensec_child_session_info,
1671         .want_feature     = gensec_child_want_feature,
1672         .have_feature     = gensec_child_have_feature,
1673         .expire_time      = gensec_child_expire_time,
1674         .final_auth_type  = gensec_child_final_auth_type,
1675         .enabled          = true,
1676         .priority         = GENSEC_SPNEGO
1677 };
1678
1679 _PUBLIC_ NTSTATUS gensec_spnego_init(TALLOC_CTX *ctx)
1680 {
1681         NTSTATUS ret;
1682         ret = gensec_register(ctx, &gensec_spnego_security_ops);
1683         if (!NT_STATUS_IS_OK(ret)) {
1684                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1685                         gensec_spnego_security_ops.name));
1686                 return ret;
1687         }
1688
1689         return ret;
1690 }