source4/auth/gensec/gensec_gssapi.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Kerberos backend for GENSEC
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   7    Copyright (C) Stefan Metzmacher <metze@samba.org> 2004-2005
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "lib/events/events.h"
  26 #include "system/kerberos.h"
  27 #include "heimdal/lib/gssapi/gssapi/gssapi.h"
  28 #include "auth/kerberos/kerberos.h"
  29 #include "librpc/gen_ndr/krb5pac.h"
  30 #include "auth/auth.h"
  31 #include "lib/ldb/include/ldb.h"
  32 #include "auth/auth_sam.h"
  33 #include "librpc/rpc/dcerpc.h"
  34 #include "auth/credentials/credentials.h"
  35 #include "auth/credentials/credentials_krb5.h"
  36 #include "auth/gensec/gensec.h"
  37 #include "param/param.h"
  38
  39 enum gensec_gssapi_sasl_state
  40 {
  41         STAGE_GSS_NEG,
  42         STAGE_SASL_SSF_NEG,
  43         STAGE_SASL_SSF_ACCEPT,
  44         STAGE_DONE
  45 };
  46
  47 #define NEG_SEAL 0x4
  48 #define NEG_SIGN 0x2
  49 #define NEG_NONE 0x1
  50
  51 struct gensec_gssapi_state {
  52         gss_ctx_id_t gssapi_context;
  53         struct gss_channel_bindings_struct *input_chan_bindings;
  54         gss_name_t server_name;
  55         gss_name_t client_name;
  56         OM_uint32 want_flags, got_flags;
  57         gss_OID gss_oid;
  58
  59         DATA_BLOB session_key;
  60         DATA_BLOB pac;
  61
  62         struct smb_krb5_context *smb_krb5_context;
  63         struct gssapi_creds_container *client_cred;
  64         struct gssapi_creds_container *server_cred;
  65
  66         gss_cred_id_t delegated_cred_handle;
  67
  68         bool sasl; /* We have two different mechs in this file: One
  69                     * for SASL wrapped GSSAPI and another for normal
  70                     * GSSAPI */
  71         enum gensec_gssapi_sasl_state sasl_state;
  72         uint8_t sasl_protection; /* What was negotiated at the SASL
  73                                   * layer, independent of the GSSAPI
  74                                   * layer... */
  75
  76         size_t max_wrap_buf_size;
  77         int gss_exchange_count;
  78 };
  79
  80 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security);
  81 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security);
  82
  83 static char *gssapi_error_string(TALLOC_CTX *mem_ctx,
  84                                  OM_uint32 maj_stat, OM_uint32 min_stat,
  85                                  const gss_OID mech)
  86 {
  87         OM_uint32 disp_min_stat, disp_maj_stat;
  88         gss_buffer_desc maj_error_message;
  89         gss_buffer_desc min_error_message;
  90         char *maj_error_string, *min_error_string;
  91         OM_uint32 msg_ctx = 0;
  92
  93         char *ret;
  94
  95         maj_error_message.value = NULL;
  96         min_error_message.value = NULL;
  97         maj_error_message.length = 0;
  98         min_error_message.length = 0;
  99
 100         disp_maj_stat = gss_display_status(&disp_min_stat, maj_stat, GSS_C_GSS_CODE,
 101                            mech, &msg_ctx, &maj_error_message);
 102         disp_maj_stat = gss_display_status(&disp_min_stat, min_stat, GSS_C_MECH_CODE,
 103                            mech, &msg_ctx, &min_error_message);
 104
 105         maj_error_string = talloc_strndup(mem_ctx, (char *)maj_error_message.value, maj_error_message.length);
 106
 107         min_error_string = talloc_strndup(mem_ctx, (char *)min_error_message.value, min_error_message.length);
 108
 109         ret = talloc_asprintf(mem_ctx, "%s: %s", maj_error_string, min_error_string);
 110
 111         talloc_free(maj_error_string);
 112         talloc_free(min_error_string);
 113
 114         gss_release_buffer(&disp_min_stat, &maj_error_message);
 115         gss_release_buffer(&disp_min_stat, &min_error_message);
 116
 117         return ret;
 118 }
 119
 120
 121 static int gensec_gssapi_destructor(struct gensec_gssapi_state *gensec_gssapi_state)
 122 {
 123         OM_uint32 maj_stat, min_stat;
 124
 125         if (gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
 126                 maj_stat = gss_release_cred(&min_stat,
 127                                             &gensec_gssapi_state->delegated_cred_handle);
 128         }
 129
 130         if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
 131                 maj_stat = gss_delete_sec_context (&min_stat,
 132                                                    &gensec_gssapi_state->gssapi_context,
 133                                                    GSS_C_NO_BUFFER);
 134         }
 135
 136         if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
 137                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->server_name);
 138         }
 139         if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
 140                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->client_name);
 141         }
 142         return 0;
 143 }
 144
 145 static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 146 {
 147         struct gensec_gssapi_state *gensec_gssapi_state;
 148         krb5_error_code ret;
 149         struct gsskrb5_send_to_kdc send_to_kdc;
 150
 151         gensec_gssapi_state = talloc(gensec_security, struct gensec_gssapi_state);
 152         if (!gensec_gssapi_state) {
 153                 return NT_STATUS_NO_MEMORY;
 154         }
 155
 156         gensec_gssapi_state->gss_exchange_count = 0;
 157         gensec_gssapi_state->max_wrap_buf_size
 158                 = lp_parm_int(gensec_security->lp_ctx, NULL, "gensec_gssapi", "max wrap buf size", 65536);
 159
 160         gensec_gssapi_state->sasl = false;
 161         gensec_gssapi_state->sasl_state = STAGE_GSS_NEG;
 162
 163         gensec_security->private_data = gensec_gssapi_state;
 164
 165         gensec_gssapi_state->gssapi_context = GSS_C_NO_CONTEXT;
 166         gensec_gssapi_state->server_name = GSS_C_NO_NAME;
 167         gensec_gssapi_state->client_name = GSS_C_NO_NAME;
 168
 169         /* TODO: Fill in channel bindings */
 170         gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
 171
 172         gensec_gssapi_state->want_flags = 0;
 173         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "mutual", true)) {
 174                 gensec_gssapi_state->want_flags |= GSS_C_MUTUAL_FLAG;
 175         }
 176         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "delegation", true)) {
 177                 gensec_gssapi_state->want_flags |= GSS_C_DELEG_FLAG;
 178         }
 179         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "replay", true)) {
 180                 gensec_gssapi_state->want_flags |= GSS_C_REPLAY_FLAG;
 181         }
 182         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "sequence", true)) {
 183                 gensec_gssapi_state->want_flags |= GSS_C_SEQUENCE_FLAG;
 184         }
 185
 186         gensec_gssapi_state->got_flags = 0;
 187
 188         gensec_gssapi_state->session_key = data_blob(NULL, 0);
 189         gensec_gssapi_state->pac = data_blob(NULL, 0);
 190
 191         gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 192
 193         talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 194
 195         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 196                 gensec_gssapi_state->want_flags |= GSS_C_INTEG_FLAG;
 197         }
 198         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 199                 gensec_gssapi_state->want_flags |= GSS_C_CONF_FLAG;
 200         }
 201         if (gensec_security->want_features & GENSEC_FEATURE_DCE_STYLE) {
 202                 gensec_gssapi_state->want_flags |= GSS_C_DCE_STYLE;
 203         }
 204
 205         gensec_gssapi_state->gss_oid = GSS_C_NULL_OID;
 206
 207         send_to_kdc.func = smb_krb5_send_and_recv_func;
 208         send_to_kdc.ptr = gensec_security->event_ctx;
 209
 210         ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
 211         if (ret) {
 212                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 213                 talloc_free(gensec_gssapi_state);
 214                 return NT_STATUS_INTERNAL_ERROR;
 215         }
 216         if (lp_realm(gensec_security->lp_ctx) && *lp_realm(gensec_security->lp_ctx)) {
 217                 char *upper_realm = strupper_talloc(gensec_gssapi_state, lp_realm(gensec_security->lp_ctx));
 218                 if (!upper_realm) {
 219                         DEBUG(1,("gensec_krb5_start: could not uppercase realm: %s\n", lp_realm(gensec_security->lp_ctx)));
 220                         talloc_free(gensec_gssapi_state);
 221                         return NT_STATUS_NO_MEMORY;
 222                 }
 223                 ret = gsskrb5_set_default_realm(upper_realm);
 224                 talloc_free(upper_realm);
 225                 if (ret) {
 226                         DEBUG(1,("gensec_krb5_start: gsskrb5_set_default_realm failed\n"));
 227                         talloc_free(gensec_gssapi_state);
 228                         return NT_STATUS_INTERNAL_ERROR;
 229                 }
 230         }
 231
 232         /* don't do DNS lookups of any kind, it might/will fail for a netbios name */
 233         ret = gsskrb5_set_dns_canonicalize(lp_parm_bool(gensec_security->lp_ctx, NULL, "krb5", "set_dns_canonicalize", false));
 234         if (ret) {
 235                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_dns_canonicalize failed\n"));
 236                 talloc_free(gensec_gssapi_state);
 237                 return NT_STATUS_INTERNAL_ERROR;
 238         }
 239
 240         ret = smb_krb5_init_context(gensec_gssapi_state,
 241                                     gensec_security->event_ctx,
 242                                     gensec_security->lp_ctx,
 243                                     &gensec_gssapi_state->smb_krb5_context);
 244         if (ret) {
 245                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n",
 246                          error_message(ret)));
 247                 talloc_free(gensec_gssapi_state);
 248                 return NT_STATUS_INTERNAL_ERROR;
 249         }
 250         return NT_STATUS_OK;
 251 }
 252
 253 static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
 254 {
 255         NTSTATUS nt_status;
 256         int ret;
 257         struct gensec_gssapi_state *gensec_gssapi_state;
 258         struct cli_credentials *machine_account;
 259         struct gssapi_creds_container *gcc;
 260
 261         nt_status = gensec_gssapi_start(gensec_security);
 262         if (!NT_STATUS_IS_OK(nt_status)) {
 263                 return nt_status;
 264         }
 265
 266         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 267
 268         machine_account = gensec_get_credentials(gensec_security);
 269
 270         if (!machine_account) {
 271                 DEBUG(3, ("No machine account credentials specified\n"));
 272                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 273         } else {
 274                 ret = cli_credentials_get_server_gss_creds(machine_account, gensec_security->lp_ctx, &gcc);
 275                 if (ret) {
 276                         DEBUG(1, ("Aquiring acceptor credentials failed: %s\n",
 277                                   error_message(ret)));
 278                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 279                 }
 280         }
 281
 282         gensec_gssapi_state->server_cred = gcc;
 283         return NT_STATUS_OK;
 284
 285 }
 286
 287 static NTSTATUS gensec_gssapi_sasl_server_start(struct gensec_security *gensec_security)
 288 {
 289         NTSTATUS nt_status;
 290         struct gensec_gssapi_state *gensec_gssapi_state;
 291         nt_status = gensec_gssapi_server_start(gensec_security);
 292
 293         if (NT_STATUS_IS_OK(nt_status)) {
 294                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 295                 gensec_gssapi_state->sasl = true;
 296         }
 297         return nt_status;
 298 }
 299
 300 static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
 301 {
 302         struct gensec_gssapi_state *gensec_gssapi_state;
 303         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 304         krb5_error_code ret;
 305         NTSTATUS nt_status;
 306         gss_buffer_desc name_token;
 307         gss_OID name_type;
 308         OM_uint32 maj_stat, min_stat;
 309         const char *hostname = gensec_get_target_hostname(gensec_security);
 310         const char *principal;
 311         struct gssapi_creds_container *gcc;
 312
 313         if (!hostname) {
 314                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 315                 return NT_STATUS_INVALID_PARAMETER;
 316         }
 317         if (is_ipaddress(hostname)) {
 318                 DEBUG(2, ("Cannot do GSSAPI to an IP address\n"));
 319                 return NT_STATUS_INVALID_PARAMETER;
 320         }
 321         if (strcmp(hostname, "localhost") == 0) {
 322                 DEBUG(2, ("GSSAPI to 'localhost' does not make sense\n"));
 323                 return NT_STATUS_INVALID_PARAMETER;
 324         }
 325
 326         nt_status = gensec_gssapi_start(gensec_security);
 327         if (!NT_STATUS_IS_OK(nt_status)) {
 328                 return nt_status;
 329         }
 330
 331         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 332
 333         gensec_gssapi_state->gss_oid = gss_mech_krb5;
 334
 335         principal = gensec_get_target_principal(gensec_security);
 336         if (principal && lp_client_use_spnego_principal(gensec_security->lp_ctx)) {
 337                 name_type = GSS_C_NULL_OID;
 338         } else {
 339                 principal = talloc_asprintf(gensec_gssapi_state, "%s@%s",
 340                                             gensec_get_target_service(gensec_security),
 341                                             hostname);
 342
 343                 name_type = GSS_C_NT_HOSTBASED_SERVICE;
 344         }
 345         name_token.value  = discard_const_p(uint8_t, principal);
 346         name_token.length = strlen(principal);
 347
 348
 349         maj_stat = gss_import_name (&min_stat,
 350                                     &name_token,
 351                                     name_type,
 352                                     &gensec_gssapi_state->server_name);
 353         if (maj_stat) {
 354                 DEBUG(2, ("GSS Import name of %s failed: %s\n",
 355                           (char *)name_token.value,
 356                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 357                 return NT_STATUS_INVALID_PARAMETER;
 358         }
 359
 360         ret = cli_credentials_get_client_gss_creds(creds, gensec_security->lp_ctx, &gcc);
 361         switch (ret) {
 362         case 0:
 363                 break;
 364         case KRB5KDC_ERR_PREAUTH_FAILED:
 365                 return NT_STATUS_LOGON_FAILURE;
 366         case KRB5_KDC_UNREACH:
 367                 DEBUG(3, ("Cannot reach a KDC we require to contact %s\n", principal));
 368                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 369         default:
 370                 DEBUG(1, ("Aquiring initiator credentials failed\n"));
 371                 return NT_STATUS_UNSUCCESSFUL;
 372         }
 373
 374         gensec_gssapi_state->client_cred = gcc;
 375         if (!talloc_reference(gensec_gssapi_state, gcc)) {
 376                 return NT_STATUS_NO_MEMORY;
 377         }
 378
 379         return NT_STATUS_OK;
 380 }
 381
 382 static NTSTATUS gensec_gssapi_sasl_client_start(struct gensec_security *gensec_security)
 383 {
 384         NTSTATUS nt_status;
 385         struct gensec_gssapi_state *gensec_gssapi_state;
 386         nt_status = gensec_gssapi_client_start(gensec_security);
 387
 388         if (NT_STATUS_IS_OK(nt_status)) {
 389                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 390                 gensec_gssapi_state->sasl = true;
 391         }
 392         return nt_status;
 393 }
 394
 395
 396 /**
 397  * Check if the packet is one for this mechansim
 398  *
 399  * @param gensec_security GENSEC state
 400  * @param in The request, as a DATA_BLOB
 401  * @return Error, INVALID_PARAMETER if it's not a packet for us
 402  *                or NT_STATUS_OK if the packet is ok.
 403  */
 404
 405 static NTSTATUS gensec_gssapi_magic(struct gensec_security *gensec_security,
 406                                     const DATA_BLOB *in)
 407 {
 408         if (gensec_gssapi_check_oid(in, GENSEC_OID_KERBEROS5)) {
 409                 return NT_STATUS_OK;
 410         } else {
 411                 return NT_STATUS_INVALID_PARAMETER;
 412         }
 413 }
 414
 415
 416 /**
 417  * Next state function for the GSSAPI GENSEC mechanism
 418  *
 419  * @param gensec_gssapi_state GSSAPI State
 420  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 421  * @param in The request, as a DATA_BLOB
 422  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 423  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 424  *                or NT_STATUS_OK if the user is authenticated.
 425  */
 426
 427 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 428                                    TALLOC_CTX *out_mem_ctx,
 429                                    const DATA_BLOB in, DATA_BLOB *out)
 430 {
 431         struct gensec_gssapi_state *gensec_gssapi_state
 432                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 433         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 434         OM_uint32 maj_stat, min_stat;
 435         OM_uint32 min_stat2;
 436         gss_buffer_desc input_token, output_token;
 437         gss_OID gss_oid_p = NULL;
 438         input_token.length = in.length;
 439         input_token.value = in.data;
 440
 441         switch (gensec_gssapi_state->sasl_state) {
 442         case STAGE_GSS_NEG:
 443         {
 444                 switch (gensec_security->gensec_role) {
 445                 case GENSEC_CLIENT:
 446                 {
 447                         maj_stat = gss_init_sec_context(&min_stat,
 448                                                         gensec_gssapi_state->client_cred->creds,
 449                                                         &gensec_gssapi_state->gssapi_context,
 450                                                         gensec_gssapi_state->server_name,
 451                                                         gensec_gssapi_state->gss_oid,
 452                                                         gensec_gssapi_state->want_flags,
 453                                                         0,
 454                                                         gensec_gssapi_state->input_chan_bindings,
 455                                                         &input_token,
 456                                                         &gss_oid_p,
 457                                                         &output_token,
 458                                                         &gensec_gssapi_state->got_flags, /* ret flags */
 459                                                         NULL);
 460                         if (gss_oid_p) {
 461                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 462                         }
 463                         break;
 464                 }
 465                 case GENSEC_SERVER:
 466                 {
 467                         maj_stat = gss_accept_sec_context(&min_stat,
 468                                                           &gensec_gssapi_state->gssapi_context,
 469                                                           gensec_gssapi_state->server_cred->creds,
 470                                                           &input_token,
 471                                                           gensec_gssapi_state->input_chan_bindings,
 472                                                           &gensec_gssapi_state->client_name,
 473                                                           &gss_oid_p,
 474                                                           &output_token,
 475                                                           &gensec_gssapi_state->got_flags,
 476                                                           NULL,
 477                                                           &gensec_gssapi_state->delegated_cred_handle);
 478                         if (gss_oid_p) {
 479                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 480                         }
 481                         break;
 482                 }
 483                 default:
 484                         return NT_STATUS_INVALID_PARAMETER;
 485
 486                 }
 487
 488                 gensec_gssapi_state->gss_exchange_count++;
 489
 490                 if (maj_stat == GSS_S_COMPLETE) {
 491                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 492                         gss_release_buffer(&min_stat2, &output_token);
 493
 494                         if (gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG) {
 495                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 496                         } else {
 497                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 498                         }
 499
 500                         /* We may have been invoked as SASL, so there
 501                          * is more work to do */
 502                         if (gensec_gssapi_state->sasl) {
 503                                 /* Due to a very subtle interaction
 504                                  * with SASL and the LDAP libs, we
 505                                  * must ensure the data pointer is
 506                                  * != NULL, but the length is 0.
 507                                  *
 508                                  * This ensures we send a 'zero
 509                                  * length' (rather than NULL) response
 510                                  */
 511
 512                                 if (!out->data) {
 513                                         out->data = (uint8_t *)talloc_strdup(out_mem_ctx, "\0");
 514                                 }
 515
 516                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 517                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 518                         } else {
 519                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 520
 521                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 522                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly sealed\n"));
 523                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 524                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly signed\n"));
 525                                 } else {
 526                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 527                                 }
 528
 529                                 return NT_STATUS_OK;
 530                         }
 531                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 532                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 533                         gss_release_buffer(&min_stat2, &output_token);
 534
 535                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 536                 } else if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
 537                         switch (min_stat) {
 538                         case KRB5_KDC_UNREACH:
 539                                 DEBUG(3, ("Cannot reach a KDC we require: %s\n",
 540                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 541                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 542                         case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 543                                 DEBUG(3, ("Server is not registered with our KDC: %s\n",
 544                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 545                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 546                         case KRB5KRB_AP_ERR_MSG_TYPE:
 547                                 /* garbage input, possibly from the auto-mech detection */
 548                                 return NT_STATUS_INVALID_PARAMETER;
 549                         default:
 550                                 DEBUG(1, ("GSS Update(krb5)(%d) Update failed: %s\n",
 551                                           gensec_gssapi_state->gss_exchange_count,
 552                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 553                                 return nt_status;
 554                         }
 555                 } else {
 556                         DEBUG(1, ("GSS Update(%d) failed: %s\n",
 557                                   gensec_gssapi_state->gss_exchange_count,
 558                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 559                         return nt_status;
 560                 }
 561                 break;
 562         }
 563
 564         /* These last two stages are only done if we were invoked as SASL */
 565         case STAGE_SASL_SSF_NEG:
 566         {
 567                 switch (gensec_security->gensec_role) {
 568                 case GENSEC_CLIENT:
 569                 {
 570                         uint8_t maxlength_proposed[4];
 571                         uint8_t maxlength_accepted[4];
 572                         uint8_t security_supported;
 573                         int conf_state;
 574                         gss_qop_t qop_state;
 575                         input_token.length = in.length;
 576                         input_token.value = in.data;
 577
 578                         /* As a client, we have just send a
 579                          * zero-length blob to the server (after the
 580                          * normal GSSAPI exchange), and it has replied
 581                          * with it's SASL negotiation */
 582
 583                         maj_stat = gss_unwrap(&min_stat,
 584                                               gensec_gssapi_state->gssapi_context,
 585                                               &input_token,
 586                                               &output_token,
 587                                               &conf_state,
 588                                               &qop_state);
 589                         if (GSS_ERROR(maj_stat)) {
 590                                 DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 591                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 592                                 return NT_STATUS_ACCESS_DENIED;
 593                         }
 594
 595                         if (output_token.length < 4) {
 596                                 return NT_STATUS_INVALID_PARAMETER;
 597                         }
 598
 599                         memcpy(maxlength_proposed, output_token.value, 4);
 600                         gss_release_buffer(&min_stat, &output_token);
 601
 602                         /* first byte is the proposed security */
 603                         security_supported = maxlength_proposed[0];
 604                         maxlength_proposed[0] = '\0';
 605
 606                         /* Rest is the proposed max wrap length */
 607                         gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_proposed, 0),
 608                                                                      gensec_gssapi_state->max_wrap_buf_size);
 609                         gensec_gssapi_state->sasl_protection = 0;
 610                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 611                                 if (security_supported & NEG_SEAL) {
 612                                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 613                                 }
 614                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 615                                 if (security_supported & NEG_SIGN) {
 616                                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 617                                 }
 618                         } else if (security_supported & NEG_NONE) {
 619                                 gensec_gssapi_state->sasl_protection |= NEG_NONE;
 620                         } else {
 621                                 DEBUG(1, ("Remote server does not support unprotected connections"));
 622                                 return NT_STATUS_ACCESS_DENIED;
 623                         }
 624
 625                         /* Send back the negotiated max length */
 626
 627                         RSIVAL(maxlength_accepted, 0, gensec_gssapi_state->max_wrap_buf_size);
 628
 629                         maxlength_accepted[0] = gensec_gssapi_state->sasl_protection;
 630
 631                         input_token.value = maxlength_accepted;
 632                         input_token.length = sizeof(maxlength_accepted);
 633
 634                         maj_stat = gss_wrap(&min_stat,
 635                                             gensec_gssapi_state->gssapi_context,
 636                                             false,
 637                                             GSS_C_QOP_DEFAULT,
 638                                             &input_token,
 639                                             &conf_state,
 640                                             &output_token);
 641                         if (GSS_ERROR(maj_stat)) {
 642                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 643                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 644                                 return NT_STATUS_ACCESS_DENIED;
 645                         }
 646
 647                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 648                         gss_release_buffer(&min_stat, &output_token);
 649
 650                         /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 651                         gensec_gssapi_state->sasl_state = STAGE_DONE;
 652
 653                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 654                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly sealed\n"));
 655                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 656                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly signed\n"));
 657                         } else {
 658                                 DEBUG(3, ("SASL/GSSAPI Connection to server will have no cryptographicly protection\n"));
 659                         }
 660
 661                         return NT_STATUS_OK;
 662                 }
 663                 case GENSEC_SERVER:
 664                 {
 665                         uint8_t maxlength_proposed[4];
 666                         uint8_t security_supported = 0x0;
 667                         int conf_state;
 668
 669                         /* As a server, we have just been sent a zero-length blob (note this, but it isn't fatal) */
 670                         if (in.length != 0) {
 671                                 DEBUG(1, ("SASL/GSSAPI: client sent non-zero length starting SASL negotiation!\n"));
 672                         }
 673
 674                         /* Give the client some idea what we will support */
 675
 676                         RSIVAL(maxlength_proposed, 0, gensec_gssapi_state->max_wrap_buf_size);
 677                         /* first byte is the proposed security */
 678                         maxlength_proposed[0] = '\0';
 679
 680                         gensec_gssapi_state->sasl_protection = 0;
 681                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 682                                 security_supported |= NEG_SEAL;
 683                         }
 684                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 685                                 security_supported |= NEG_SIGN;
 686                         }
 687                         if (security_supported == 0) {
 688                                 /* If we don't support anything, this must be 0 */
 689                                 RSIVAL(maxlength_proposed, 0, 0x0);
 690                         }
 691
 692                         /* TODO:  We may not wish to support this */
 693                         security_supported |= NEG_NONE;
 694                         maxlength_proposed[0] = security_supported;
 695
 696                         input_token.value = maxlength_proposed;
 697                         input_token.length = sizeof(maxlength_proposed);
 698
 699                         maj_stat = gss_wrap(&min_stat,
 700                                             gensec_gssapi_state->gssapi_context,
 701                                             false,
 702                                             GSS_C_QOP_DEFAULT,
 703                                             &input_token,
 704                                             &conf_state,
 705                                             &output_token);
 706                         if (GSS_ERROR(maj_stat)) {
 707                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 708                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 709                                 return NT_STATUS_ACCESS_DENIED;
 710                         }
 711
 712                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 713                         gss_release_buffer(&min_stat, &output_token);
 714
 715                         gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_ACCEPT;
 716                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 717                 }
 718                 default:
 719                         return NT_STATUS_INVALID_PARAMETER;
 720
 721                 }
 722         }
 723         /* This is s server-only stage */
 724         case STAGE_SASL_SSF_ACCEPT:
 725         {
 726                 uint8_t maxlength_accepted[4];
 727                 uint8_t security_accepted;
 728                 int conf_state;
 729                 gss_qop_t qop_state;
 730                 input_token.length = in.length;
 731                 input_token.value = in.data;
 732
 733                 maj_stat = gss_unwrap(&min_stat,
 734                                       gensec_gssapi_state->gssapi_context,
 735                                       &input_token,
 736                                       &output_token,
 737                                       &conf_state,
 738                                       &qop_state);
 739                 if (GSS_ERROR(maj_stat)) {
 740                         DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 741                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 742                         return NT_STATUS_ACCESS_DENIED;
 743                 }
 744
 745                 if (output_token.length < 4) {
 746                         return NT_STATUS_INVALID_PARAMETER;
 747                 }
 748
 749                 memcpy(maxlength_accepted, output_token.value, 4);
 750                 gss_release_buffer(&min_stat, &output_token);
 751
 752                 /* first byte is the proposed security */
 753                 security_accepted = maxlength_accepted[0];
 754                 maxlength_accepted[0] = '\0';
 755
 756                 /* Rest is the proposed max wrap length */
 757                 gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_accepted, 0),
 758                                                              gensec_gssapi_state->max_wrap_buf_size);
 759
 760                 gensec_gssapi_state->sasl_protection = 0;
 761                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 762                         if (security_accepted & NEG_SEAL) {
 763                                 gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 764                         }
 765                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 766                         if (security_accepted & NEG_SIGN) {
 767                                 gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 768                         }
 769                 } else if (security_accepted & NEG_NONE) {
 770                         gensec_gssapi_state->sasl_protection |= NEG_NONE;
 771                 } else {
 772                         DEBUG(1, ("Remote client does not support unprotected connections, but we failed to negotiate anything better"));
 773                         return NT_STATUS_ACCESS_DENIED;
 774                 }
 775
 776                 /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 777                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 778                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 779                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly sealed\n"));
 780                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 781                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly signed\n"));
 782                 } else {
 783                         DEBUG(5, ("SASL/GSSAPI Connection from client will have no cryptographic protection\n"));
 784                 }
 785
 786                 *out = data_blob(NULL, 0);
 787                 return NT_STATUS_OK;
 788         }
 789         default:
 790                 return NT_STATUS_INVALID_PARAMETER;
 791         }
 792 }
 793
 794 static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security,
 795                                    TALLOC_CTX *mem_ctx,
 796                                    const DATA_BLOB *in,
 797                                    DATA_BLOB *out)
 798 {
 799         struct gensec_gssapi_state *gensec_gssapi_state
 800                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 801         OM_uint32 maj_stat, min_stat;
 802         gss_buffer_desc input_token, output_token;
 803         int conf_state;
 804         input_token.length = in->length;
 805         input_token.value = in->data;
 806
 807         maj_stat = gss_wrap(&min_stat,
 808                             gensec_gssapi_state->gssapi_context,
 809                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 810                             GSS_C_QOP_DEFAULT,
 811                             &input_token,
 812                             &conf_state,
 813                             &output_token);
 814         if (GSS_ERROR(maj_stat)) {
 815                 DEBUG(1, ("gensec_gssapi_wrap: GSS Wrap failed: %s\n",
 816                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 817                 return NT_STATUS_ACCESS_DENIED;
 818         }
 819
 820         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 821         gss_release_buffer(&min_stat, &output_token);
 822
 823         if (gensec_gssapi_state->sasl) {
 824                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 825                 if (max_wrapped_size < out->length) {
 826                         DEBUG(1, ("gensec_gssapi_wrap: when wrapped, INPUT data (%u) is grew to be larger than SASL negotiated maximum output size (%u > %u)\n",
 827                                   (unsigned)in->length,
 828                                   (unsigned)out->length,
 829                                   (unsigned int)max_wrapped_size));
 830                         return NT_STATUS_INVALID_PARAMETER;
 831                 }
 832         }
 833
 834         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 835             && !conf_state) {
 836                 return NT_STATUS_ACCESS_DENIED;
 837         }
 838         return NT_STATUS_OK;
 839 }
 840
 841 static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security,
 842                                      TALLOC_CTX *mem_ctx,
 843                                      const DATA_BLOB *in,
 844                                      DATA_BLOB *out)
 845 {
 846         struct gensec_gssapi_state *gensec_gssapi_state
 847                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 848         OM_uint32 maj_stat, min_stat;
 849         gss_buffer_desc input_token, output_token;
 850         int conf_state;
 851         gss_qop_t qop_state;
 852         input_token.length = in->length;
 853         input_token.value = in->data;
 854
 855         if (gensec_gssapi_state->sasl) {
 856                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 857                 if (max_wrapped_size < in->length) {
 858                         DEBUG(1, ("gensec_gssapi_unwrap: WRAPPED data is larger than SASL negotiated maximum size\n"));
 859                         return NT_STATUS_INVALID_PARAMETER;
 860                 }
 861         }
 862
 863         maj_stat = gss_unwrap(&min_stat,
 864                               gensec_gssapi_state->gssapi_context,
 865                               &input_token,
 866                               &output_token,
 867                               &conf_state,
 868                               &qop_state);
 869         if (GSS_ERROR(maj_stat)) {
 870                 DEBUG(1, ("gensec_gssapi_unwrap: GSS UnWrap failed: %s\n",
 871                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 872                 return NT_STATUS_ACCESS_DENIED;
 873         }
 874
 875         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 876         gss_release_buffer(&min_stat, &output_token);
 877
 878         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 879             && !conf_state) {
 880                 return NT_STATUS_ACCESS_DENIED;
 881         }
 882         return NT_STATUS_OK;
 883 }
 884
 885 /* Find out the maximum input size negotiated on this connection */
 886
 887 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security)
 888 {
 889         struct gensec_gssapi_state *gensec_gssapi_state
 890                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 891         OM_uint32 maj_stat, min_stat;
 892         OM_uint32 max_input_size;
 893
 894         maj_stat = gss_wrap_size_limit(&min_stat,
 895                                        gensec_gssapi_state->gssapi_context,
 896                                        gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 897                                        GSS_C_QOP_DEFAULT,
 898                                        gensec_gssapi_state->max_wrap_buf_size,
 899                                        &max_input_size);
 900         if (GSS_ERROR(maj_stat)) {
 901                 TALLOC_CTX *mem_ctx = talloc_new(NULL);
 902                 DEBUG(1, ("gensec_gssapi_max_input_size: determinaing signature size with gss_wrap_size_limit failed: %s\n",
 903                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 904                 talloc_free(mem_ctx);
 905                 return 0;
 906         }
 907
 908         return max_input_size;
 909 }
 910
 911 /* Find out the maximum output size negotiated on this connection */
 912 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security)
 913 {
 914         struct gensec_gssapi_state *gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);;
 915         return gensec_gssapi_state->max_wrap_buf_size;
 916 }
 917
 918 static NTSTATUS gensec_gssapi_seal_packet(struct gensec_security *gensec_security,
 919                                           TALLOC_CTX *mem_ctx,
 920                                           uint8_t *data, size_t length,
 921                                           const uint8_t *whole_pdu, size_t pdu_length,
 922                                           DATA_BLOB *sig)
 923 {
 924         struct gensec_gssapi_state *gensec_gssapi_state
 925                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 926         OM_uint32 maj_stat, min_stat;
 927         gss_buffer_desc input_token, output_token;
 928         int conf_state;
 929         ssize_t sig_length;
 930
 931         input_token.length = length;
 932         input_token.value = data;
 933
 934         maj_stat = gss_wrap(&min_stat,
 935                             gensec_gssapi_state->gssapi_context,
 936                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 937                             GSS_C_QOP_DEFAULT,
 938                             &input_token,
 939                             &conf_state,
 940                             &output_token);
 941         if (GSS_ERROR(maj_stat)) {
 942                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap failed: %s\n",
 943                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 944                 return NT_STATUS_ACCESS_DENIED;
 945         }
 946
 947         if (output_token.length < input_token.length) {
 948                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
 949                           (long)output_token.length, (long)length));
 950                 return NT_STATUS_INTERNAL_ERROR;
 951         }
 952         sig_length = output_token.length - input_token.length;
 953
 954         memcpy(data, ((uint8_t *)output_token.value) + sig_length, length);
 955         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
 956
 957         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
 958         dump_data_pw("gensec_gssapi_seal_packet: clear\n", data, length);
 959         dump_data_pw("gensec_gssapi_seal_packet: sealed\n", ((uint8_t *)output_token.value) + sig_length, output_token.length - sig_length);
 960
 961         gss_release_buffer(&min_stat, &output_token);
 962
 963         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 964             && !conf_state) {
 965                 return NT_STATUS_ACCESS_DENIED;
 966         }
 967         return NT_STATUS_OK;
 968 }
 969
 970 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
 971                                             TALLOC_CTX *mem_ctx,
 972                                             uint8_t *data, size_t length,
 973                                             const uint8_t *whole_pdu, size_t pdu_length,
 974                                             const DATA_BLOB *sig)
 975 {
 976         struct gensec_gssapi_state *gensec_gssapi_state
 977                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 978         OM_uint32 maj_stat, min_stat;
 979         gss_buffer_desc input_token, output_token;
 980         int conf_state;
 981         gss_qop_t qop_state;
 982         DATA_BLOB in;
 983
 984         dump_data_pw("gensec_gssapi_unseal_packet: sig\n", sig->data, sig->length);
 985
 986         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
 987
 988         memcpy(in.data, sig->data, sig->length);
 989         memcpy(in.data + sig->length, data, length);
 990
 991         input_token.length = in.length;
 992         input_token.value = in.data;
 993
 994         maj_stat = gss_unwrap(&min_stat,
 995                               gensec_gssapi_state->gssapi_context,
 996                               &input_token,
 997                               &output_token,
 998                               &conf_state,
 999                               &qop_state);
1000         if (GSS_ERROR(maj_stat)) {
1001                 DEBUG(1, ("gensec_gssapi_unseal_packet: GSS UnWrap failed: %s\n",
1002                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1003                 return NT_STATUS_ACCESS_DENIED;
1004         }
1005
1006         if (output_token.length != length) {
1007                 return NT_STATUS_INTERNAL_ERROR;
1008         }
1009
1010         memcpy(data, output_token.value, length);
1011
1012         gss_release_buffer(&min_stat, &output_token);
1013
1014         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1015             && !conf_state) {
1016                 return NT_STATUS_ACCESS_DENIED;
1017         }
1018         return NT_STATUS_OK;
1019 }
1020
1021 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1022                                           TALLOC_CTX *mem_ctx,
1023                                           const uint8_t *data, size_t length,
1024                                           const uint8_t *whole_pdu, size_t pdu_length,
1025                                           DATA_BLOB *sig)
1026 {
1027         struct gensec_gssapi_state *gensec_gssapi_state
1028                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1029         OM_uint32 maj_stat, min_stat;
1030         gss_buffer_desc input_token, output_token;
1031         int conf_state;
1032         ssize_t sig_length = 0;
1033
1034         input_token.length = length;
1035         input_token.value = discard_const_p(uint8_t *, data);
1036
1037         maj_stat = gss_wrap(&min_stat,
1038                             gensec_gssapi_state->gssapi_context,
1039                             0,
1040                             GSS_C_QOP_DEFAULT,
1041                             &input_token,
1042                             &conf_state,
1043                             &output_token);
1044         if (GSS_ERROR(maj_stat)) {
1045                 DEBUG(1, ("GSS Wrap failed: %s\n",
1046                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1047                 return NT_STATUS_ACCESS_DENIED;
1048         }
1049
1050         if (output_token.length < input_token.length) {
1051                 DEBUG(1, ("gensec_gssapi_sign_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
1052                           (long)output_token.length, (long)length));
1053                 return NT_STATUS_INTERNAL_ERROR;
1054         }
1055
1056         /* Caller must pad to right boundary */
1057         sig_length = output_token.length - input_token.length;
1058
1059         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
1060
1061         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1062
1063         gss_release_buffer(&min_stat, &output_token);
1064
1065         return NT_STATUS_OK;
1066 }
1067
1068 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1069                                            TALLOC_CTX *mem_ctx,
1070                                            const uint8_t *data, size_t length,
1071                                            const uint8_t *whole_pdu, size_t pdu_length,
1072                                            const DATA_BLOB *sig)
1073 {
1074         struct gensec_gssapi_state *gensec_gssapi_state
1075                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1076         OM_uint32 maj_stat, min_stat;
1077         gss_buffer_desc input_token, output_token;
1078         int conf_state;
1079         gss_qop_t qop_state;
1080         DATA_BLOB in;
1081
1082         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1083
1084         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
1085
1086         memcpy(in.data, sig->data, sig->length);
1087         memcpy(in.data + sig->length, data, length);
1088
1089         input_token.length = in.length;
1090         input_token.value = in.data;
1091
1092         maj_stat = gss_unwrap(&min_stat,
1093                               gensec_gssapi_state->gssapi_context,
1094                               &input_token,
1095                               &output_token,
1096                               &conf_state,
1097                               &qop_state);
1098         if (GSS_ERROR(maj_stat)) {
1099                 DEBUG(1, ("GSS UnWrap failed: %s\n",
1100                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1101                 return NT_STATUS_ACCESS_DENIED;
1102         }
1103
1104         if (output_token.length != length) {
1105                 return NT_STATUS_INTERNAL_ERROR;
1106         }
1107
1108         gss_release_buffer(&min_stat, &output_token);
1109
1110         return NT_STATUS_OK;
1111 }
1112
1113 /* Try to figure out what features we actually got on the connection */
1114 static bool gensec_gssapi_have_feature(struct gensec_security *gensec_security,
1115                                        uint32_t feature)
1116 {
1117         struct gensec_gssapi_state *gensec_gssapi_state
1118                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1119         if (feature & GENSEC_FEATURE_SIGN) {
1120                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1121                 if (gensec_gssapi_state->sasl
1122                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1123                         return ((gensec_gssapi_state->sasl_protection & NEG_SIGN)
1124                                 && (gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG));
1125                 }
1126                 return gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG;
1127         }
1128         if (feature & GENSEC_FEATURE_SEAL) {
1129                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1130                 if (gensec_gssapi_state->sasl
1131                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1132                         return ((gensec_gssapi_state->sasl_protection & NEG_SEAL)
1133                                  && (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG));
1134                 }
1135                 return gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG;
1136         }
1137         if (feature & GENSEC_FEATURE_SESSION_KEY) {
1138                 /* Only for GSSAPI/Krb5 */
1139                 if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
1140                         return true;
1141                 }
1142         }
1143         if (feature & GENSEC_FEATURE_DCE_STYLE) {
1144                 return gensec_gssapi_state->got_flags & GSS_C_DCE_STYLE;
1145         }
1146         /* We can always do async (rather than strict request/reply) packets.  */
1147         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1148                 return true;
1149         }
1150         return false;
1151 }
1152
1153 /*
1154  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1155  * (for encrypting some passwords).
1156  *
1157  * This breaks all the abstractions, but what do you expect...
1158  */
1159 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1160                                           DATA_BLOB *session_key)
1161 {
1162         struct gensec_gssapi_state *gensec_gssapi_state
1163                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1164         OM_uint32 maj_stat, min_stat;
1165         krb5_keyblock *subkey;
1166
1167         if (gensec_gssapi_state->session_key.data) {
1168                 *session_key = gensec_gssapi_state->session_key;
1169                 return NT_STATUS_OK;
1170         }
1171
1172         maj_stat = gsskrb5_get_initiator_subkey(&min_stat,
1173                                                 gensec_gssapi_state->gssapi_context,
1174                                                 &subkey);
1175         if (maj_stat != 0) {
1176                 DEBUG(1, ("NO session key for this mech\n"));
1177                 return NT_STATUS_NO_USER_SESSION_KEY;
1178         }
1179
1180         DEBUG(10, ("Got KRB5 session key of length %d\n",
1181                    (int)KRB5_KEY_LENGTH(subkey)));
1182         gensec_gssapi_state->session_key = data_blob_talloc(gensec_gssapi_state,
1183                                                             KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
1184         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context, subkey);
1185         *session_key = gensec_gssapi_state->session_key;
1186         dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
1187
1188         return NT_STATUS_OK;
1189 }
1190
1191 /* Get some basic (and authorization) information about the user on
1192  * this session.  This uses either the PAC (if present) or a local
1193  * database lookup */
1194 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1195                                            struct auth_session_info **_session_info)
1196 {
1197         NTSTATUS nt_status;
1198         TALLOC_CTX *mem_ctx;
1199         struct gensec_gssapi_state *gensec_gssapi_state
1200                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1201         struct auth_serversupplied_info *server_info = NULL;
1202         struct auth_session_info *session_info = NULL;
1203         struct PAC_LOGON_INFO *logon_info;
1204         OM_uint32 maj_stat, min_stat;
1205         gss_buffer_desc name_token;
1206         gss_buffer_desc pac;
1207         krb5_keyblock *keyblock;
1208         time_t authtime;
1209         krb5_principal principal;
1210         char *principal_string;
1211         DATA_BLOB pac_blob;
1212
1213         if ((gensec_gssapi_state->gss_oid->length != gss_mech_krb5->length)
1214             || (memcmp(gensec_gssapi_state->gss_oid->elements, gss_mech_krb5->elements,
1215                        gensec_gssapi_state->gss_oid->length) != 0)) {
1216                 DEBUG(1, ("NO session info available for this mech\n"));
1217                 return NT_STATUS_INVALID_PARAMETER;
1218         }
1219
1220         mem_ctx = talloc_named(gensec_gssapi_state, 0, "gensec_gssapi_session_info context");
1221         NT_STATUS_HAVE_NO_MEMORY(mem_ctx);
1222
1223         maj_stat = gss_display_name (&min_stat,
1224                                      gensec_gssapi_state->client_name,
1225                                      &name_token,
1226                                      NULL);
1227         if (GSS_ERROR(maj_stat)) {
1228                 DEBUG(1, ("GSS display_name failed: %s\n",
1229                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1230                 talloc_free(mem_ctx);
1231                 return NT_STATUS_FOOBAR;
1232         }
1233
1234         principal_string = talloc_strndup(mem_ctx,
1235                                           (const char *)name_token.value,
1236                                           name_token.length);
1237
1238         gss_release_buffer(&min_stat, &name_token);
1239
1240         if (!principal_string) {
1241                 talloc_free(mem_ctx);
1242                 return NT_STATUS_NO_MEMORY;
1243         }
1244
1245         maj_stat = gsskrb5_extract_authz_data_from_sec_context(&min_stat,
1246                                                                gensec_gssapi_state->gssapi_context,
1247                                                                KRB5_AUTHDATA_WIN2K_PAC,
1248                                                                &pac);
1249
1250
1251         if (maj_stat == 0) {
1252                 pac_blob = data_blob_talloc(mem_ctx, pac.value, pac.length);
1253                 gss_release_buffer(&min_stat, &pac);
1254
1255         } else {
1256                 pac_blob = data_blob(NULL, 0);
1257         }
1258
1259         /* IF we have the PAC - otherwise we need to get this
1260          * data from elsewere - local ldb, or (TODO) lookup of some
1261          * kind...
1262          */
1263         if (pac_blob.length) {
1264                 krb5_error_code ret;
1265                 union netr_Validation validation;
1266
1267                 maj_stat = gsskrb5_extract_authtime_from_sec_context(&min_stat,
1268                                                                      gensec_gssapi_state->gssapi_context,
1269                                                                      &authtime);
1270
1271                 if (GSS_ERROR(maj_stat)) {
1272                         DEBUG(1, ("gsskrb5_extract_authtime_from_sec_context: %s\n",
1273                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1274                         talloc_free(mem_ctx);
1275                         return NT_STATUS_FOOBAR;
1276                 }
1277
1278                 maj_stat = gsskrb5_extract_service_keyblock(&min_stat,
1279                                                             gensec_gssapi_state->gssapi_context,
1280                                                             &keyblock);
1281
1282                 if (GSS_ERROR(maj_stat)) {
1283                         DEBUG(1, ("gsskrb5_copy_service_keyblock failed: %s\n",
1284                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1285                         talloc_free(mem_ctx);
1286                         return NT_STATUS_FOOBAR;
1287                 }
1288
1289                 ret = krb5_parse_name_flags(gensec_gssapi_state->smb_krb5_context->krb5_context,
1290                                             principal_string,
1291                                             KRB5_PRINCIPAL_PARSE_MUST_REALM,
1292                                             &principal);
1293                 if (ret) {
1294                         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context,
1295                                            keyblock);
1296                         talloc_free(mem_ctx);
1297                         return NT_STATUS_INVALID_PARAMETER;
1298                 }
1299
1300                 /* decode and verify the pac */
1301                 nt_status = kerberos_pac_logon_info(mem_ctx, lp_iconv_convenience(gensec_security->lp_ctx), &logon_info, pac_blob,
1302                                                     gensec_gssapi_state->smb_krb5_context->krb5_context,
1303                                                     NULL, keyblock, principal, authtime, NULL);
1304                 krb5_free_principal(gensec_gssapi_state->smb_krb5_context->krb5_context, principal);
1305                 krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context,
1306                                    keyblock);
1307
1308                 if (!NT_STATUS_IS_OK(nt_status)) {
1309                         talloc_free(mem_ctx);
1310                         return nt_status;
1311                 }
1312                 validation.sam3 = &logon_info->info3;
1313                 nt_status = make_server_info_netlogon_validation(gensec_gssapi_state,
1314                                                                  NULL,
1315                                                                  3, &validation,
1316                                                                  &server_info);
1317                 if (!NT_STATUS_IS_OK(nt_status)) {
1318                         talloc_free(mem_ctx);
1319                         return nt_status;
1320                 }
1321         } else if (!lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec", "require_pac", false)) {
1322                 DEBUG(1, ("Unable to find PAC, resorting to local user lookup: %s\n",
1323                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1324                 nt_status = sam_get_server_info_principal(mem_ctx, gensec_security->lp_ctx, principal_string,
1325                                                           &server_info);
1326
1327                 if (!NT_STATUS_IS_OK(nt_status)) {
1328                         talloc_free(mem_ctx);
1329                         return nt_status;
1330                 }
1331         } else {
1332                 DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access: %s\n",
1333                           principal_string,
1334                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1335                 return NT_STATUS_ACCESS_DENIED;
1336         }
1337
1338         /* references the server_info into the session_info */
1339         nt_status = auth_generate_session_info(mem_ctx, gensec_security->lp_ctx, server_info, &session_info);
1340         if (!NT_STATUS_IS_OK(nt_status)) {
1341                 talloc_free(mem_ctx);
1342                 return nt_status;
1343         }
1344
1345         nt_status = gensec_gssapi_session_key(gensec_security, &session_info->session_key);
1346         if (!NT_STATUS_IS_OK(nt_status)) {
1347                 talloc_free(mem_ctx);
1348                 return nt_status;
1349         }
1350
1351         if (!(gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG)) {
1352                 DEBUG(10, ("gensec_gssapi: NO delegated credentials supplied by client\n"));
1353         } else {
1354                 krb5_error_code ret;
1355                 DEBUG(10, ("gensec_gssapi: delegated credentials supplied by client\n"));
1356                 session_info->credentials = cli_credentials_init(session_info);
1357                 if (!session_info->credentials) {
1358                         talloc_free(mem_ctx);
1359                         return NT_STATUS_NO_MEMORY;
1360                 }
1361
1362                 cli_credentials_set_event_context(session_info->credentials, gensec_security->event_ctx);
1363                 cli_credentials_set_conf(session_info->credentials, gensec_security->lp_ctx);
1364                 /* Just so we don't segfault trying to get at a username */
1365                 cli_credentials_set_anonymous(session_info->credentials);
1366
1367                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1368                                                            gensec_security->lp_ctx,
1369                                                            gensec_gssapi_state->delegated_cred_handle,
1370                                                            CRED_SPECIFIED);
1371                 if (ret) {
1372                         talloc_free(mem_ctx);
1373                         return NT_STATUS_NO_MEMORY;
1374                 }
1375
1376                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1377                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1378
1379                 /* It has been taken from this place... */
1380                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1381         }
1382         talloc_steal(gensec_gssapi_state, session_info);
1383         talloc_free(mem_ctx);
1384         *_session_info = session_info;
1385
1386         return NT_STATUS_OK;
1387 }
1388
1389 static const char *gensec_gssapi_krb5_oids[] = {
1390         GENSEC_OID_KERBEROS5_OLD,
1391         GENSEC_OID_KERBEROS5,
1392         NULL
1393 };
1394
1395 static const char *gensec_gssapi_spnego_oids[] = {
1396         GENSEC_OID_SPNEGO,
1397         NULL
1398 };
1399
1400 /* As a server, this could in theory accept any GSSAPI mech */
1401 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1402         .name           = "gssapi_spnego",
1403         .sasl_name      = "GSS-SPNEGO",
1404         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1405         .oid            = gensec_gssapi_spnego_oids,
1406         .client_start   = gensec_gssapi_client_start,
1407         .server_start   = gensec_gssapi_server_start,
1408         .magic          = gensec_gssapi_magic,
1409         .update         = gensec_gssapi_update,
1410         .session_key    = gensec_gssapi_session_key,
1411         .session_info   = gensec_gssapi_session_info,
1412         .sign_packet    = gensec_gssapi_sign_packet,
1413         .check_packet   = gensec_gssapi_check_packet,
1414         .seal_packet    = gensec_gssapi_seal_packet,
1415         .unseal_packet  = gensec_gssapi_unseal_packet,
1416         .wrap           = gensec_gssapi_wrap,
1417         .unwrap         = gensec_gssapi_unwrap,
1418         .have_feature   = gensec_gssapi_have_feature,
1419         .enabled        = false,
1420         .kerberos       = true,
1421         .priority       = GENSEC_GSSAPI
1422 };
1423
1424 /* As a server, this could in theory accept any GSSAPI mech */
1425 static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
1426         .name           = "gssapi_krb5",
1427         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1428         .oid            = gensec_gssapi_krb5_oids,
1429         .client_start   = gensec_gssapi_client_start,
1430         .server_start   = gensec_gssapi_server_start,
1431         .magic          = gensec_gssapi_magic,
1432         .update         = gensec_gssapi_update,
1433         .session_key    = gensec_gssapi_session_key,
1434         .session_info   = gensec_gssapi_session_info,
1435         .sign_packet    = gensec_gssapi_sign_packet,
1436         .check_packet   = gensec_gssapi_check_packet,
1437         .seal_packet    = gensec_gssapi_seal_packet,
1438         .unseal_packet  = gensec_gssapi_unseal_packet,
1439         .wrap           = gensec_gssapi_wrap,
1440         .unwrap         = gensec_gssapi_unwrap,
1441         .have_feature   = gensec_gssapi_have_feature,
1442         .enabled        = true,
1443         .kerberos       = true,
1444         .priority       = GENSEC_GSSAPI
1445 };
1446
1447 /* As a server, this could in theory accept any GSSAPI mech */
1448 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1449         .name             = "gssapi_krb5_sasl",
1450         .sasl_name        = "GSSAPI",
1451         .client_start     = gensec_gssapi_sasl_client_start,
1452         .server_start     = gensec_gssapi_sasl_server_start,
1453         .update           = gensec_gssapi_update,
1454         .session_key      = gensec_gssapi_session_key,
1455         .session_info     = gensec_gssapi_session_info,
1456         .max_input_size   = gensec_gssapi_max_input_size,
1457         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1458         .wrap             = gensec_gssapi_wrap,
1459         .unwrap           = gensec_gssapi_unwrap,
1460         .have_feature     = gensec_gssapi_have_feature,
1461         .enabled          = true,
1462         .kerberos         = true,
1463         .priority         = GENSEC_GSSAPI
1464 };
1465
1466 _PUBLIC_ NTSTATUS gensec_gssapi_init(void)
1467 {
1468         NTSTATUS ret;
1469
1470         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1471         if (!NT_STATUS_IS_OK(ret)) {
1472                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1473                         gensec_gssapi_spnego_security_ops.name));
1474                 return ret;
1475         }
1476
1477         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1478         if (!NT_STATUS_IS_OK(ret)) {
1479                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1480                         gensec_gssapi_krb5_security_ops.name));
1481                 return ret;
1482         }
1483
1484         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1485         if (!NT_STATUS_IS_OK(ret)) {
1486                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1487                         gensec_gssapi_sasl_krb5_security_ops.name));
1488                 return ret;
1489         }
1490
1491         return ret;
1492 }