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