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 "system/gssapi.h"
  28 #include "auth/kerberos/kerberos.h"
  29 #include "librpc/gen_ndr/krb5pac.h"
  30 #include "auth/auth.h"
  31 #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 "auth/gensec/gensec_proto.h"
  38 #include "auth/gensec/gensec_toplevel_proto.h"
  39 #include "param/param.h"
  40 #include "auth/session_proto.h"
  41 #include "gensec_gssapi.h"
  42 #include "lib/util/util_net.h"
  43 #include "auth/kerberos/pac_utils.h"
  44
  45 _PUBLIC_ NTSTATUS gensec_gssapi_init(void);
  46
  47 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security);
  48 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security);
  49
  50 static int gensec_gssapi_destructor(struct gensec_gssapi_state *gensec_gssapi_state)
  51 {
  52         OM_uint32 maj_stat, min_stat;
  53
  54         if (gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
  55                 maj_stat = gss_release_cred(&min_stat,
  56                                             &gensec_gssapi_state->delegated_cred_handle);
  57         }
  58
  59         if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
  60                 maj_stat = gss_delete_sec_context (&min_stat,
  61                                                    &gensec_gssapi_state->gssapi_context,
  62                                                    GSS_C_NO_BUFFER);
  63         }
  64
  65         if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
  66                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->server_name);
  67         }
  68         if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
  69                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->client_name);
  70         }
  71
  72         if (gensec_gssapi_state->lucid) {
  73                 gss_krb5_free_lucid_sec_context(&min_stat, gensec_gssapi_state->lucid);
  74         }
  75
  76         return 0;
  77 }
  78
  79 static NTSTATUS gensec_gssapi_init_lucid(struct gensec_gssapi_state *gensec_gssapi_state)
  80 {
  81         OM_uint32 maj_stat, min_stat;
  82
  83         if (gensec_gssapi_state->lucid) {
  84                 return NT_STATUS_OK;
  85         }
  86
  87         maj_stat = gss_krb5_export_lucid_sec_context(&min_stat,
  88                                                      &gensec_gssapi_state->gssapi_context,
  89                                                      1,
  90                                                      (void **)&gensec_gssapi_state->lucid);
  91         if (maj_stat != GSS_S_COMPLETE) {
  92                 DEBUG(0,("gensec_gssapi_init_lucid: %s\n",
  93                         gssapi_error_string(gensec_gssapi_state,
  94                                             maj_stat, min_stat,
  95                                             gensec_gssapi_state->gss_oid)));
  96                 return NT_STATUS_INTERNAL_ERROR;
  97         }
  98
  99         if (gensec_gssapi_state->lucid->version != 1) {
 100                 DEBUG(0,("gensec_gssapi_init_lucid: lucid version[%d] != 1\n",
 101                         gensec_gssapi_state->lucid->version));
 102                 gss_krb5_free_lucid_sec_context(&min_stat, gensec_gssapi_state->lucid);
 103                 gensec_gssapi_state->lucid = NULL;
 104                 return NT_STATUS_INTERNAL_ERROR;
 105         }
 106
 107         return NT_STATUS_OK;
 108 }
 109
 110 static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 111 {
 112         struct gensec_gssapi_state *gensec_gssapi_state;
 113         krb5_error_code ret;
 114         const char *realm;
 115
 116         gensec_gssapi_state = talloc_zero(gensec_security, struct gensec_gssapi_state);
 117         if (!gensec_gssapi_state) {
 118                 return NT_STATUS_NO_MEMORY;
 119         }
 120
 121         gensec_security->private_data = gensec_gssapi_state;
 122
 123         gensec_gssapi_state->gssapi_context = GSS_C_NO_CONTEXT;
 124
 125         /* TODO: Fill in channel bindings */
 126         gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
 127
 128         gensec_gssapi_state->server_name = GSS_C_NO_NAME;
 129         gensec_gssapi_state->client_name = GSS_C_NO_NAME;
 130
 131         gensec_gssapi_state->gss_want_flags = 0;
 132
 133         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation_by_kdc_policy", true)) {
 134                 gensec_gssapi_state->gss_want_flags |= GSS_C_DELEG_POLICY_FLAG;
 135         }
 136         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "mutual", true)) {
 137                 gensec_gssapi_state->gss_want_flags |= GSS_C_MUTUAL_FLAG;
 138         }
 139         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation", true)) {
 140                 gensec_gssapi_state->gss_want_flags |= GSS_C_DELEG_FLAG;
 141         }
 142         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "replay", true)) {
 143                 gensec_gssapi_state->gss_want_flags |= GSS_C_REPLAY_FLAG;
 144         }
 145         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "sequence", true)) {
 146                 gensec_gssapi_state->gss_want_flags |= GSS_C_SEQUENCE_FLAG;
 147         }
 148
 149         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 150                 gensec_gssapi_state->gss_want_flags |= GSS_C_INTEG_FLAG;
 151         }
 152         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 153                 gensec_gssapi_state->gss_want_flags |= GSS_C_INTEG_FLAG;
 154                 gensec_gssapi_state->gss_want_flags |= GSS_C_CONF_FLAG;
 155         }
 156         if (gensec_security->want_features & GENSEC_FEATURE_DCE_STYLE) {
 157                 gensec_gssapi_state->gss_want_flags |= GSS_C_DCE_STYLE;
 158         }
 159
 160         gensec_gssapi_state->gss_got_flags = 0;
 161
 162         switch (gensec_security->ops->auth_type) {
 163         case DCERPC_AUTH_TYPE_SPNEGO:
 164                 gensec_gssapi_state->gss_oid = gss_mech_spnego;
 165                 break;
 166         case DCERPC_AUTH_TYPE_KRB5:
 167         default:
 168                 gensec_gssapi_state->gss_oid = gss_mech_krb5;
 169                 break;
 170         }
 171
 172         ret = smb_krb5_init_context(gensec_gssapi_state,
 173                                     NULL,
 174                                     gensec_security->settings->lp_ctx,
 175                                     &gensec_gssapi_state->smb_krb5_context);
 176         if (ret) {
 177                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n",
 178                          error_message(ret)));
 179                 talloc_free(gensec_gssapi_state);
 180                 return NT_STATUS_INTERNAL_ERROR;
 181         }
 182
 183         gensec_gssapi_state->client_cred = NULL;
 184         gensec_gssapi_state->server_cred = NULL;
 185
 186         gensec_gssapi_state->lucid = NULL;
 187
 188         gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 189
 190         gensec_gssapi_state->sasl = false;
 191         gensec_gssapi_state->sasl_state = STAGE_GSS_NEG;
 192         gensec_gssapi_state->sasl_protection = 0;
 193
 194         gensec_gssapi_state->max_wrap_buf_size
 195                 = gensec_setting_int(gensec_security->settings, "gensec_gssapi", "max wrap buf size", 65536);
 196         gensec_gssapi_state->gss_exchange_count = 0;
 197         gensec_gssapi_state->sig_size = 0;
 198
 199         talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 200
 201         realm = lpcfg_realm(gensec_security->settings->lp_ctx);
 202         if (realm != NULL) {
 203                 ret = gsskrb5_set_default_realm(realm);
 204                 if (ret) {
 205                         DEBUG(1,("gensec_krb5_start: gsskrb5_set_default_realm failed\n"));
 206                         talloc_free(gensec_gssapi_state);
 207                         return NT_STATUS_INTERNAL_ERROR;
 208                 }
 209         }
 210
 211         /* don't do DNS lookups of any kind, it might/will fail for a netbios name */
 212         ret = gsskrb5_set_dns_canonicalize(gensec_setting_bool(gensec_security->settings, "krb5", "set_dns_canonicalize", false));
 213         if (ret) {
 214                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_dns_canonicalize failed\n"));
 215                 talloc_free(gensec_gssapi_state);
 216                 return NT_STATUS_INTERNAL_ERROR;
 217         }
 218
 219         return NT_STATUS_OK;
 220 }
 221
 222 static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
 223 {
 224         NTSTATUS nt_status;
 225         int ret;
 226         struct gensec_gssapi_state *gensec_gssapi_state;
 227         struct cli_credentials *machine_account;
 228         struct gssapi_creds_container *gcc;
 229
 230         nt_status = gensec_gssapi_start(gensec_security);
 231         if (!NT_STATUS_IS_OK(nt_status)) {
 232                 return nt_status;
 233         }
 234
 235         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 236
 237         machine_account = gensec_get_credentials(gensec_security);
 238
 239         if (!machine_account) {
 240                 DEBUG(3, ("No machine account credentials specified\n"));
 241                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 242         } else {
 243                 ret = cli_credentials_get_server_gss_creds(machine_account,
 244                                                            gensec_security->settings->lp_ctx, &gcc);
 245                 if (ret) {
 246                         DEBUG(1, ("Aquiring acceptor credentials failed: %s\n",
 247                                   error_message(ret)));
 248                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 249                 }
 250         }
 251
 252         gensec_gssapi_state->server_cred = gcc;
 253         return NT_STATUS_OK;
 254
 255 }
 256
 257 static NTSTATUS gensec_gssapi_sasl_server_start(struct gensec_security *gensec_security)
 258 {
 259         NTSTATUS nt_status;
 260         struct gensec_gssapi_state *gensec_gssapi_state;
 261         nt_status = gensec_gssapi_server_start(gensec_security);
 262
 263         if (NT_STATUS_IS_OK(nt_status)) {
 264                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 265                 gensec_gssapi_state->sasl = true;
 266         }
 267         return nt_status;
 268 }
 269
 270 static NTSTATUS gensec_gssapi_client_creds(struct gensec_security *gensec_security,
 271                                            struct tevent_context *ev)
 272 {
 273         struct gensec_gssapi_state *gensec_gssapi_state;
 274         struct gssapi_creds_container *gcc;
 275         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 276         const char *error_string;
 277         int ret;
 278
 279         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 280
 281         /* Only run this the first time the update() call is made */
 282         if (gensec_gssapi_state->client_cred) {
 283                 return NT_STATUS_OK;
 284         }
 285
 286         ret = cli_credentials_get_client_gss_creds(creds,
 287                                                    ev,
 288                                                    gensec_security->settings->lp_ctx, &gcc, &error_string);
 289         switch (ret) {
 290         case 0:
 291                 break;
 292         case EINVAL:
 293                 DEBUG(3, ("Cannot obtain client GSS credentials we need to contact %s : %s\n", gensec_gssapi_state->target_principal, error_string));
 294                 return NT_STATUS_INVALID_PARAMETER;
 295         case KRB5KDC_ERR_PREAUTH_FAILED:
 296         case KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN:
 297                 DEBUG(1, ("Wrong username or password: %s\n", error_string));
 298                 return NT_STATUS_LOGON_FAILURE;
 299         case KRB5_KDC_UNREACH:
 300                 DEBUG(3, ("Cannot reach a KDC we require to contact %s : %s\n", gensec_gssapi_state->target_principal, error_string));
 301                 return NT_STATUS_NO_LOGON_SERVERS;
 302         case KRB5_CC_NOTFOUND:
 303         case KRB5_CC_END:
 304                 DEBUG(2, ("Error obtaining ticket we require to contact %s: (possibly due to clock skew between us and the KDC) %s\n", gensec_gssapi_state->target_principal, error_string));
 305                 return NT_STATUS_TIME_DIFFERENCE_AT_DC;
 306         default:
 307                 DEBUG(1, ("Aquiring initiator credentials failed: %s\n", error_string));
 308                 return NT_STATUS_UNSUCCESSFUL;
 309         }
 310
 311         gensec_gssapi_state->client_cred = gcc;
 312         if (!talloc_reference(gensec_gssapi_state, gcc)) {
 313                 return NT_STATUS_NO_MEMORY;
 314         }
 315
 316         return NT_STATUS_OK;
 317 }
 318
 319 static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
 320 {
 321         struct gensec_gssapi_state *gensec_gssapi_state;
 322         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 323         NTSTATUS nt_status;
 324         gss_buffer_desc name_token;
 325         gss_OID name_type;
 326         OM_uint32 maj_stat, min_stat;
 327         const char *hostname = gensec_get_target_hostname(gensec_security);
 328
 329         if (!hostname) {
 330                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 331                 return NT_STATUS_INVALID_PARAMETER;
 332         }
 333         if (is_ipaddress(hostname)) {
 334                 DEBUG(2, ("Cannot do GSSAPI to an IP address\n"));
 335                 return NT_STATUS_INVALID_PARAMETER;
 336         }
 337         if (strcmp(hostname, "localhost") == 0) {
 338                 DEBUG(2, ("GSSAPI to 'localhost' does not make sense\n"));
 339                 return NT_STATUS_INVALID_PARAMETER;
 340         }
 341
 342         nt_status = gensec_gssapi_start(gensec_security);
 343         if (!NT_STATUS_IS_OK(nt_status)) {
 344                 return nt_status;
 345         }
 346
 347         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 348
 349         if (cli_credentials_get_impersonate_principal(creds)) {
 350                 gensec_gssapi_state->gss_want_flags &= ~(GSS_C_DELEG_FLAG|GSS_C_DELEG_POLICY_FLAG);
 351         }
 352
 353         gensec_gssapi_state->target_principal = gensec_get_target_principal(gensec_security);
 354         if (gensec_gssapi_state->target_principal) {
 355                 name_type = GSS_C_NULL_OID;
 356         } else {
 357                 gensec_gssapi_state->target_principal = talloc_asprintf(gensec_gssapi_state, "%s/%s@%s",
 358                                             gensec_get_target_service(gensec_security),
 359                                             hostname, lpcfg_realm(gensec_security->settings->lp_ctx));
 360
 361                 name_type = GSS_C_NT_USER_NAME;
 362         }
 363         name_token.value  = discard_const_p(uint8_t, gensec_gssapi_state->target_principal);
 364         name_token.length = strlen(gensec_gssapi_state->target_principal);
 365
 366
 367         maj_stat = gss_import_name (&min_stat,
 368                                     &name_token,
 369                                     name_type,
 370                                     &gensec_gssapi_state->server_name);
 371         if (maj_stat) {
 372                 DEBUG(2, ("GSS Import name of %s failed: %s\n",
 373                           (char *)name_token.value,
 374                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 375                 return NT_STATUS_INVALID_PARAMETER;
 376         }
 377
 378         return NT_STATUS_OK;
 379 }
 380
 381 static NTSTATUS gensec_gssapi_sasl_client_start(struct gensec_security *gensec_security)
 382 {
 383         NTSTATUS nt_status;
 384         struct gensec_gssapi_state *gensec_gssapi_state;
 385         nt_status = gensec_gssapi_client_start(gensec_security);
 386
 387         if (NT_STATUS_IS_OK(nt_status)) {
 388                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 389                 gensec_gssapi_state->sasl = true;
 390         }
 391         return nt_status;
 392 }
 393
 394
 395 /**
 396  * Next state function for the GSSAPI GENSEC mechanism
 397  *
 398  * @param gensec_gssapi_state GSSAPI State
 399  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 400  * @param in The request, as a DATA_BLOB
 401  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 402  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 403  *                or NT_STATUS_OK if the user is authenticated.
 404  */
 405
 406 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 407                                      TALLOC_CTX *out_mem_ctx,
 408                                      struct tevent_context *ev,
 409                                      const DATA_BLOB in, DATA_BLOB *out)
 410 {
 411         struct gensec_gssapi_state *gensec_gssapi_state
 412                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 413         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 414         OM_uint32 maj_stat, min_stat;
 415         OM_uint32 min_stat2;
 416         gss_buffer_desc input_token, output_token;
 417         gss_OID gss_oid_p = NULL;
 418         input_token.length = in.length;
 419         input_token.value = in.data;
 420
 421         switch (gensec_gssapi_state->sasl_state) {
 422         case STAGE_GSS_NEG:
 423         {
 424                 switch (gensec_security->gensec_role) {
 425                 case GENSEC_CLIENT:
 426                 {
 427                         struct gsskrb5_send_to_kdc send_to_kdc;
 428                         krb5_error_code ret;
 429
 430                         nt_status = gensec_gssapi_client_creds(gensec_security, ev);
 431                         if (!NT_STATUS_IS_OK(nt_status)) {
 432                                 return nt_status;
 433                         }
 434
 435 #ifdef SAMBA4_USES_HEIMDAL
 436                         send_to_kdc.func = smb_krb5_send_and_recv_func;
 437                         send_to_kdc.ptr = ev;
 438 #endif
 439
 440                         min_stat = gsskrb5_set_send_to_kdc(&send_to_kdc);
 441                         if (min_stat) {
 442                                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 443                                 return NT_STATUS_INTERNAL_ERROR;
 444                         }
 445
 446                         maj_stat = gss_init_sec_context(&min_stat,
 447                                                         gensec_gssapi_state->client_cred->creds,
 448                                                         &gensec_gssapi_state->gssapi_context,
 449                                                         gensec_gssapi_state->server_name,
 450                                                         gensec_gssapi_state->gss_oid,
 451                                                         gensec_gssapi_state->gss_want_flags,
 452                                                         0,
 453                                                         gensec_gssapi_state->input_chan_bindings,
 454                                                         &input_token,
 455                                                         &gss_oid_p,
 456                                                         &output_token,
 457                                                         &gensec_gssapi_state->gss_got_flags, /* ret flags */
 458                                                         NULL);
 459                         if (gss_oid_p) {
 460                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 461                         }
 462
 463 #ifdef SAMBA4_USES_HEIMDAL
 464                         send_to_kdc.func = smb_krb5_send_and_recv_func;
 465                         send_to_kdc.ptr = NULL;
 466 #endif
 467
 468                         ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
 469                         if (ret) {
 470                                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 471                                 return NT_STATUS_INTERNAL_ERROR;
 472                         }
 473
 474                         break;
 475                 }
 476                 case GENSEC_SERVER:
 477                 {
 478                         maj_stat = gss_accept_sec_context(&min_stat,
 479                                                           &gensec_gssapi_state->gssapi_context,
 480                                                           gensec_gssapi_state->server_cred->creds,
 481                                                           &input_token,
 482                                                           gensec_gssapi_state->input_chan_bindings,
 483                                                           &gensec_gssapi_state->client_name,
 484                                                           &gss_oid_p,
 485                                                           &output_token,
 486                                                           &gensec_gssapi_state->gss_got_flags,
 487                                                           NULL,
 488                                                           &gensec_gssapi_state->delegated_cred_handle);
 489                         if (gss_oid_p) {
 490                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 491                         }
 492                         break;
 493                 }
 494                 default:
 495                         return NT_STATUS_INVALID_PARAMETER;
 496
 497                 }
 498
 499                 gensec_gssapi_state->gss_exchange_count++;
 500
 501                 if (maj_stat == GSS_S_COMPLETE) {
 502                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 503                         gss_release_buffer(&min_stat2, &output_token);
 504
 505                         if (gensec_gssapi_state->gss_got_flags & GSS_C_DELEG_FLAG) {
 506                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 507                         } else {
 508                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 509                         }
 510
 511                         /* We may have been invoked as SASL, so there
 512                          * is more work to do */
 513                         if (gensec_gssapi_state->sasl) {
 514                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 515                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 516                         } else {
 517                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 518
 519                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 520                                         DEBUG(5, ("GSSAPI Connection will be cryptographically sealed\n"));
 521                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 522                                         DEBUG(5, ("GSSAPI Connection will be cryptographically signed\n"));
 523                                 } else {
 524                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 525                                 }
 526
 527                                 return NT_STATUS_OK;
 528                         }
 529                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 530                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 531                         gss_release_buffer(&min_stat2, &output_token);
 532
 533                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 534                 } else if (maj_stat == GSS_S_CONTEXT_EXPIRED) {
 535                         gss_cred_id_t creds;
 536                         gss_name_t name;
 537                         gss_buffer_desc buffer;
 538                         OM_uint32 lifetime = 0;
 539                         gss_cred_usage_t usage;
 540                         const char *role = NULL;
 541                         DEBUG(0, ("GSS %s Update(krb5)(%d) Update failed, credentials expired during GSSAPI handshake!\n",
 542                                   role,
 543                                   gensec_gssapi_state->gss_exchange_count));
 544
 545
 546                         switch (gensec_security->gensec_role) {
 547                         case GENSEC_CLIENT:
 548                                 creds = gensec_gssapi_state->client_cred->creds;
 549                                 role = "client";
 550                         case GENSEC_SERVER:
 551                                 creds = gensec_gssapi_state->server_cred->creds;
 552                                 role = "server";
 553                         }
 554
 555                         maj_stat = gss_inquire_cred(&min_stat,
 556                                                     creds,
 557                                                     &name, &lifetime, &usage, NULL);
 558
 559                         if (maj_stat == GSS_S_COMPLETE) {
 560                                 const char *usage_string;
 561                                 switch (usage) {
 562                                 case GSS_C_BOTH:
 563                                         usage_string = "GSS_C_BOTH";
 564                                         break;
 565                                 case GSS_C_ACCEPT:
 566                                         usage_string = "GSS_C_ACCEPT";
 567                                         break;
 568                                 case GSS_C_INITIATE:
 569                                         usage_string = "GSS_C_INITIATE";
 570                                         break;
 571                                 }
 572                                 maj_stat = gss_display_name(&min_stat, name, &buffer, NULL);
 573                                 if (maj_stat) {
 574                                         buffer.value = NULL;
 575                                         buffer.length = 0;
 576                                 }
 577                                 if (lifetime > 0) {
 578                                         DEBUG(0, ("GSSAPI gss_inquire_cred indicates expiry of %*.*s in %u sec for %s\n",
 579                                                   (int)buffer.length, (int)buffer.length, (char *)buffer.value,
 580                                                   lifetime, usage_string));
 581                                 } else {
 582                                         DEBUG(0, ("GSSAPI gss_inquire_cred indicates %*.*s has already expired for %s\n",
 583                                                   (int)buffer.length, (int)buffer.length, (char *)buffer.value,
 584                                                   usage_string));
 585                                 }
 586                                 gss_release_buffer(&min_stat, &buffer);
 587                                 gss_release_name(&min_stat, &name);
 588                         } else if (maj_stat != GSS_S_COMPLETE) {
 589                                 DEBUG(0, ("inquiry of credential lifefime via GSSAPI gss_inquire_cred failed: %s\n",
 590                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 591                         }
 592                         return NT_STATUS_INVALID_PARAMETER;
 593                 } else if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
 594                         switch (min_stat) {
 595                         case KRB5KRB_AP_ERR_TKT_NYV:
 596                                 DEBUG(1, ("Error with ticket to contact %s: possible clock skew between us and the KDC or target server: %s\n",
 597                                           gensec_gssapi_state->target_principal,
 598                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 599                                 return NT_STATUS_TIME_DIFFERENCE_AT_DC; /* Make SPNEGO ignore us, we can't go any further here */
 600                         case KRB5KRB_AP_ERR_TKT_EXPIRED:
 601                                 DEBUG(1, ("Error with ticket to contact %s: ticket is expired, possible clock skew between us and the KDC or target server: %s\n",
 602                                           gensec_gssapi_state->target_principal,
 603                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 604                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 605                         case KRB5_KDC_UNREACH:
 606                                 DEBUG(3, ("Cannot reach a KDC we require in order to obtain a ticetk to %s: %s\n",
 607                                           gensec_gssapi_state->target_principal,
 608                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 609                                 return NT_STATUS_NO_LOGON_SERVERS; /* Make SPNEGO ignore us, we can't go any further here */
 610                         case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 611                                 DEBUG(3, ("Server %s is not registered with our KDC: %s\n",
 612                                           gensec_gssapi_state->target_principal,
 613                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 614                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 615                         case KRB5KRB_AP_ERR_MSG_TYPE:
 616                                 /* garbage input, possibly from the auto-mech detection */
 617                                 return NT_STATUS_INVALID_PARAMETER;
 618                         default:
 619                                 DEBUG(1, ("GSS %s Update(krb5)(%d) Update failed: %s\n",
 620                                           gensec_security->gensec_role == GENSEC_CLIENT ? "client" : "server",
 621                                           gensec_gssapi_state->gss_exchange_count,
 622                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 623                                 return nt_status;
 624                         }
 625                 } else {
 626                         DEBUG(1, ("GSS %s Update(%d) failed: %s\n",
 627                                   gensec_security->gensec_role == GENSEC_CLIENT ? "client" : "server",
 628                                   gensec_gssapi_state->gss_exchange_count,
 629                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 630                         return nt_status;
 631                 }
 632                 break;
 633         }
 634
 635         /* These last two stages are only done if we were invoked as SASL */
 636         case STAGE_SASL_SSF_NEG:
 637         {
 638                 switch (gensec_security->gensec_role) {
 639                 case GENSEC_CLIENT:
 640                 {
 641                         uint8_t maxlength_proposed[4];
 642                         uint8_t maxlength_accepted[4];
 643                         uint8_t security_supported;
 644                         int conf_state;
 645                         gss_qop_t qop_state;
 646                         input_token.length = in.length;
 647                         input_token.value = in.data;
 648
 649                         /* As a client, we have just send a
 650                          * zero-length blob to the server (after the
 651                          * normal GSSAPI exchange), and it has replied
 652                          * with it's SASL negotiation */
 653
 654                         maj_stat = gss_unwrap(&min_stat,
 655                                               gensec_gssapi_state->gssapi_context,
 656                                               &input_token,
 657                                               &output_token,
 658                                               &conf_state,
 659                                               &qop_state);
 660                         if (GSS_ERROR(maj_stat)) {
 661                                 DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 662                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 663                                 return NT_STATUS_ACCESS_DENIED;
 664                         }
 665
 666                         if (output_token.length < 4) {
 667                                 return NT_STATUS_INVALID_PARAMETER;
 668                         }
 669
 670                         memcpy(maxlength_proposed, output_token.value, 4);
 671                         gss_release_buffer(&min_stat, &output_token);
 672
 673                         /* first byte is the proposed security */
 674                         security_supported = maxlength_proposed[0];
 675                         maxlength_proposed[0] = '\0';
 676
 677                         /* Rest is the proposed max wrap length */
 678                         gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_proposed, 0),
 679                                                                      gensec_gssapi_state->max_wrap_buf_size);
 680                         gensec_gssapi_state->sasl_protection = 0;
 681                         if (security_supported & NEG_SEAL) {
 682                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 683                                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 684                                 }
 685                         }
 686                         if (security_supported & NEG_SIGN) {
 687                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 688                                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 689                                 }
 690                         }
 691                         if (security_supported & NEG_NONE) {
 692                                 gensec_gssapi_state->sasl_protection |= NEG_NONE;
 693                         }
 694                         if (gensec_gssapi_state->sasl_protection == 0) {
 695                                 DEBUG(1, ("Remote server does not support unprotected connections\n"));
 696                                 return NT_STATUS_ACCESS_DENIED;
 697                         }
 698
 699                         /* Send back the negotiated max length */
 700
 701                         RSIVAL(maxlength_accepted, 0, gensec_gssapi_state->max_wrap_buf_size);
 702
 703                         maxlength_accepted[0] = gensec_gssapi_state->sasl_protection;
 704
 705                         input_token.value = maxlength_accepted;
 706                         input_token.length = sizeof(maxlength_accepted);
 707
 708                         maj_stat = gss_wrap(&min_stat,
 709                                             gensec_gssapi_state->gssapi_context,
 710                                             false,
 711                                             GSS_C_QOP_DEFAULT,
 712                                             &input_token,
 713                                             &conf_state,
 714                                             &output_token);
 715                         if (GSS_ERROR(maj_stat)) {
 716                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 717                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 718                                 return NT_STATUS_ACCESS_DENIED;
 719                         }
 720
 721                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 722                         gss_release_buffer(&min_stat, &output_token);
 723
 724                         /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 725                         gensec_gssapi_state->sasl_state = STAGE_DONE;
 726
 727                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 728                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographically sealed\n"));
 729                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 730                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographically signed\n"));
 731                         } else {
 732                                 DEBUG(3, ("SASL/GSSAPI Connection to server will have no cryptographically protection\n"));
 733                         }
 734
 735                         return NT_STATUS_OK;
 736                 }
 737                 case GENSEC_SERVER:
 738                 {
 739                         uint8_t maxlength_proposed[4];
 740                         uint8_t security_supported = 0x0;
 741                         int conf_state;
 742
 743                         /* As a server, we have just been sent a zero-length blob (note this, but it isn't fatal) */
 744                         if (in.length != 0) {
 745                                 DEBUG(1, ("SASL/GSSAPI: client sent non-zero length starting SASL negotiation!\n"));
 746                         }
 747
 748                         /* Give the client some idea what we will support */
 749
 750                         RSIVAL(maxlength_proposed, 0, gensec_gssapi_state->max_wrap_buf_size);
 751                         /* first byte is the proposed security */
 752                         maxlength_proposed[0] = '\0';
 753
 754                         gensec_gssapi_state->sasl_protection = 0;
 755                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 756                                 security_supported |= NEG_SEAL;
 757                         }
 758                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 759                                 security_supported |= NEG_SIGN;
 760                         }
 761                         if (security_supported == 0) {
 762                                 /* If we don't support anything, this must be 0 */
 763                                 RSIVAL(maxlength_proposed, 0, 0x0);
 764                         }
 765
 766                         /* TODO:  We may not wish to support this */
 767                         security_supported |= NEG_NONE;
 768                         maxlength_proposed[0] = security_supported;
 769
 770                         input_token.value = maxlength_proposed;
 771                         input_token.length = sizeof(maxlength_proposed);
 772
 773                         maj_stat = gss_wrap(&min_stat,
 774                                             gensec_gssapi_state->gssapi_context,
 775                                             false,
 776                                             GSS_C_QOP_DEFAULT,
 777                                             &input_token,
 778                                             &conf_state,
 779                                             &output_token);
 780                         if (GSS_ERROR(maj_stat)) {
 781                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 782                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 783                                 return NT_STATUS_ACCESS_DENIED;
 784                         }
 785
 786                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 787                         gss_release_buffer(&min_stat, &output_token);
 788
 789                         gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_ACCEPT;
 790                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 791                 }
 792                 default:
 793                         return NT_STATUS_INVALID_PARAMETER;
 794
 795                 }
 796         }
 797         /* This is s server-only stage */
 798         case STAGE_SASL_SSF_ACCEPT:
 799         {
 800                 uint8_t maxlength_accepted[4];
 801                 uint8_t security_accepted;
 802                 int conf_state;
 803                 gss_qop_t qop_state;
 804                 input_token.length = in.length;
 805                 input_token.value = in.data;
 806
 807                 maj_stat = gss_unwrap(&min_stat,
 808                                       gensec_gssapi_state->gssapi_context,
 809                                       &input_token,
 810                                       &output_token,
 811                                       &conf_state,
 812                                       &qop_state);
 813                 if (GSS_ERROR(maj_stat)) {
 814                         DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 815                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 816                         return NT_STATUS_ACCESS_DENIED;
 817                 }
 818
 819                 if (output_token.length < 4) {
 820                         return NT_STATUS_INVALID_PARAMETER;
 821                 }
 822
 823                 memcpy(maxlength_accepted, output_token.value, 4);
 824                 gss_release_buffer(&min_stat, &output_token);
 825
 826                 /* first byte is the proposed security */
 827                 security_accepted = maxlength_accepted[0];
 828                 maxlength_accepted[0] = '\0';
 829
 830                 /* Rest is the proposed max wrap length */
 831                 gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_accepted, 0),
 832                                                              gensec_gssapi_state->max_wrap_buf_size);
 833
 834                 gensec_gssapi_state->sasl_protection = 0;
 835                 if (security_accepted & NEG_SEAL) {
 836                         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 837                                 DEBUG(1, ("Remote client wanted seal, but gensec refused\n"));
 838                                 return NT_STATUS_ACCESS_DENIED;
 839                         }
 840                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 841                 }
 842                 if (security_accepted & NEG_SIGN) {
 843                         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 844                                 DEBUG(1, ("Remote client wanted sign, but gensec refused\n"));
 845                                 return NT_STATUS_ACCESS_DENIED;
 846                         }
 847                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 848                 }
 849                 if (security_accepted & NEG_NONE) {
 850                         gensec_gssapi_state->sasl_protection |= NEG_NONE;
 851                 }
 852
 853                 /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 854                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 855                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 856                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographically sealed\n"));
 857                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 858                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographically signed\n"));
 859                 } else {
 860                         DEBUG(5, ("SASL/GSSAPI Connection from client will have no cryptographic protection\n"));
 861                 }
 862
 863                 *out = data_blob(NULL, 0);
 864                 return NT_STATUS_OK;
 865         }
 866         default:
 867                 return NT_STATUS_INVALID_PARAMETER;
 868         }
 869 }
 870
 871 static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security,
 872                                    TALLOC_CTX *mem_ctx,
 873                                    const DATA_BLOB *in,
 874                                    DATA_BLOB *out)
 875 {
 876         struct gensec_gssapi_state *gensec_gssapi_state
 877                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 878         OM_uint32 maj_stat, min_stat;
 879         gss_buffer_desc input_token, output_token;
 880         int conf_state;
 881         input_token.length = in->length;
 882         input_token.value = in->data;
 883
 884         maj_stat = gss_wrap(&min_stat,
 885                             gensec_gssapi_state->gssapi_context,
 886                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 887                             GSS_C_QOP_DEFAULT,
 888                             &input_token,
 889                             &conf_state,
 890                             &output_token);
 891         if (GSS_ERROR(maj_stat)) {
 892                 DEBUG(1, ("gensec_gssapi_wrap: GSS Wrap failed: %s\n",
 893                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 894                 return NT_STATUS_ACCESS_DENIED;
 895         }
 896
 897         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 898         gss_release_buffer(&min_stat, &output_token);
 899
 900         if (gensec_gssapi_state->sasl) {
 901                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 902                 if (max_wrapped_size < out->length) {
 903                         DEBUG(1, ("gensec_gssapi_wrap: when wrapped, INPUT data (%u) is grew to be larger than SASL negotiated maximum output size (%u > %u)\n",
 904                                   (unsigned)in->length,
 905                                   (unsigned)out->length,
 906                                   (unsigned int)max_wrapped_size));
 907                         return NT_STATUS_INVALID_PARAMETER;
 908                 }
 909         }
 910
 911         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 912             && !conf_state) {
 913                 return NT_STATUS_ACCESS_DENIED;
 914         }
 915         return NT_STATUS_OK;
 916 }
 917
 918 static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security,
 919                                      TALLOC_CTX *mem_ctx,
 920                                      const DATA_BLOB *in,
 921                                      DATA_BLOB *out)
 922 {
 923         struct gensec_gssapi_state *gensec_gssapi_state
 924                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 925         OM_uint32 maj_stat, min_stat;
 926         gss_buffer_desc input_token, output_token;
 927         int conf_state;
 928         gss_qop_t qop_state;
 929         input_token.length = in->length;
 930         input_token.value = in->data;
 931
 932         if (gensec_gssapi_state->sasl) {
 933                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 934                 if (max_wrapped_size < in->length) {
 935                         DEBUG(1, ("gensec_gssapi_unwrap: WRAPPED data is larger than SASL negotiated maximum size\n"));
 936                         return NT_STATUS_INVALID_PARAMETER;
 937                 }
 938         }
 939
 940         maj_stat = gss_unwrap(&min_stat,
 941                               gensec_gssapi_state->gssapi_context,
 942                               &input_token,
 943                               &output_token,
 944                               &conf_state,
 945                               &qop_state);
 946         if (GSS_ERROR(maj_stat)) {
 947                 DEBUG(1, ("gensec_gssapi_unwrap: GSS UnWrap failed: %s\n",
 948                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 949                 return NT_STATUS_ACCESS_DENIED;
 950         }
 951
 952         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 953         gss_release_buffer(&min_stat, &output_token);
 954
 955         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 956             && !conf_state) {
 957                 return NT_STATUS_ACCESS_DENIED;
 958         }
 959         return NT_STATUS_OK;
 960 }
 961
 962 /* Find out the maximum input size negotiated on this connection */
 963
 964 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security)
 965 {
 966         struct gensec_gssapi_state *gensec_gssapi_state
 967                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 968         OM_uint32 maj_stat, min_stat;
 969         OM_uint32 max_input_size;
 970
 971         maj_stat = gss_wrap_size_limit(&min_stat,
 972                                        gensec_gssapi_state->gssapi_context,
 973                                        gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 974                                        GSS_C_QOP_DEFAULT,
 975                                        gensec_gssapi_state->max_wrap_buf_size,
 976                                        &max_input_size);
 977         if (GSS_ERROR(maj_stat)) {
 978                 TALLOC_CTX *mem_ctx = talloc_new(NULL);
 979                 DEBUG(1, ("gensec_gssapi_max_input_size: determinaing signature size with gss_wrap_size_limit failed: %s\n",
 980                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 981                 talloc_free(mem_ctx);
 982                 return 0;
 983         }
 984
 985         return max_input_size;
 986 }
 987
 988 /* Find out the maximum output size negotiated on this connection */
 989 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security)
 990 {
 991         struct gensec_gssapi_state *gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);;
 992         return gensec_gssapi_state->max_wrap_buf_size;
 993 }
 994
 995 static NTSTATUS gensec_gssapi_seal_packet(struct gensec_security *gensec_security,
 996                                           TALLOC_CTX *mem_ctx,
 997                                           uint8_t *data, size_t length,
 998                                           const uint8_t *whole_pdu, size_t pdu_length,
 999                                           DATA_BLOB *sig)
1000 {
1001         struct gensec_gssapi_state *gensec_gssapi_state
1002                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1003         OM_uint32 maj_stat, min_stat;
1004         gss_buffer_desc input_token, output_token;
1005         int conf_state;
1006         ssize_t sig_length;
1007
1008         input_token.length = length;
1009         input_token.value = data;
1010
1011         maj_stat = gss_wrap(&min_stat,
1012                             gensec_gssapi_state->gssapi_context,
1013                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
1014                             GSS_C_QOP_DEFAULT,
1015                             &input_token,
1016                             &conf_state,
1017                             &output_token);
1018         if (GSS_ERROR(maj_stat)) {
1019                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap failed: %s\n",
1020                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1021                 return NT_STATUS_ACCESS_DENIED;
1022         }
1023
1024         if (output_token.length < input_token.length) {
1025                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
1026                           (long)output_token.length, (long)length));
1027                 return NT_STATUS_INTERNAL_ERROR;
1028         }
1029         sig_length = output_token.length - input_token.length;
1030
1031         memcpy(data, ((uint8_t *)output_token.value) + sig_length, length);
1032         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
1033
1034         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1035         dump_data_pw("gensec_gssapi_seal_packet: clear\n", data, length);
1036         dump_data_pw("gensec_gssapi_seal_packet: sealed\n", ((uint8_t *)output_token.value) + sig_length, output_token.length - sig_length);
1037
1038         gss_release_buffer(&min_stat, &output_token);
1039
1040         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1041             && !conf_state) {
1042                 return NT_STATUS_ACCESS_DENIED;
1043         }
1044         return NT_STATUS_OK;
1045 }
1046
1047 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
1048                                             uint8_t *data, size_t length,
1049                                             const uint8_t *whole_pdu, size_t pdu_length,
1050                                             const DATA_BLOB *sig)
1051 {
1052         struct gensec_gssapi_state *gensec_gssapi_state
1053                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1054         OM_uint32 maj_stat, min_stat;
1055         gss_buffer_desc input_token, output_token;
1056         int conf_state;
1057         gss_qop_t qop_state;
1058         DATA_BLOB in;
1059
1060         dump_data_pw("gensec_gssapi_unseal_packet: sig\n", sig->data, sig->length);
1061
1062         in = data_blob_talloc(gensec_security, NULL, sig->length + length);
1063
1064         memcpy(in.data, sig->data, sig->length);
1065         memcpy(in.data + sig->length, data, length);
1066
1067         input_token.length = in.length;
1068         input_token.value = in.data;
1069
1070         maj_stat = gss_unwrap(&min_stat,
1071                               gensec_gssapi_state->gssapi_context,
1072                               &input_token,
1073                               &output_token,
1074                               &conf_state,
1075                               &qop_state);
1076         talloc_free(in.data);
1077         if (GSS_ERROR(maj_stat)) {
1078                 char *error_string = gssapi_error_string(NULL, maj_stat, min_stat, gensec_gssapi_state->gss_oid);
1079                 DEBUG(1, ("gensec_gssapi_unseal_packet: GSS UnWrap failed: %s\n",
1080                           error_string));
1081                 talloc_free(error_string);
1082                 return NT_STATUS_ACCESS_DENIED;
1083         }
1084
1085         if (output_token.length != length) {
1086                 return NT_STATUS_INTERNAL_ERROR;
1087         }
1088
1089         memcpy(data, output_token.value, length);
1090
1091         gss_release_buffer(&min_stat, &output_token);
1092
1093         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1094             && !conf_state) {
1095                 return NT_STATUS_ACCESS_DENIED;
1096         }
1097         return NT_STATUS_OK;
1098 }
1099
1100 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1101                                           TALLOC_CTX *mem_ctx,
1102                                           const uint8_t *data, size_t length,
1103                                           const uint8_t *whole_pdu, size_t pdu_length,
1104                                           DATA_BLOB *sig)
1105 {
1106         struct gensec_gssapi_state *gensec_gssapi_state
1107                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1108         OM_uint32 maj_stat, min_stat;
1109         gss_buffer_desc input_token, output_token;
1110
1111         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1112                 input_token.length = pdu_length;
1113                 input_token.value = discard_const_p(uint8_t *, whole_pdu);
1114         } else {
1115                 input_token.length = length;
1116                 input_token.value = discard_const_p(uint8_t *, data);
1117         }
1118
1119         maj_stat = gss_get_mic(&min_stat,
1120                             gensec_gssapi_state->gssapi_context,
1121                             GSS_C_QOP_DEFAULT,
1122                             &input_token,
1123                             &output_token);
1124         if (GSS_ERROR(maj_stat)) {
1125                 DEBUG(1, ("GSS GetMic failed: %s\n",
1126                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1127                 return NT_STATUS_ACCESS_DENIED;
1128         }
1129
1130         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, output_token.length);
1131
1132         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1133
1134         gss_release_buffer(&min_stat, &output_token);
1135
1136         return NT_STATUS_OK;
1137 }
1138
1139 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1140                                            const uint8_t *data, size_t length,
1141                                            const uint8_t *whole_pdu, size_t pdu_length,
1142                                            const DATA_BLOB *sig)
1143 {
1144         struct gensec_gssapi_state *gensec_gssapi_state
1145                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1146         OM_uint32 maj_stat, min_stat;
1147         gss_buffer_desc input_token;
1148         gss_buffer_desc input_message;
1149         gss_qop_t qop_state;
1150
1151         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1152
1153         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1154                 input_message.length = pdu_length;
1155                 input_message.value = discard_const(whole_pdu);
1156         } else {
1157                 input_message.length = length;
1158                 input_message.value = discard_const(data);
1159         }
1160
1161         input_token.length = sig->length;
1162         input_token.value = sig->data;
1163
1164         maj_stat = gss_verify_mic(&min_stat,
1165                               gensec_gssapi_state->gssapi_context,
1166                               &input_message,
1167                               &input_token,
1168                               &qop_state);
1169         if (GSS_ERROR(maj_stat)) {
1170                 char *error_string = gssapi_error_string(NULL, maj_stat, min_stat, gensec_gssapi_state->gss_oid);
1171                 DEBUG(1, ("GSS VerifyMic failed: %s\n", error_string));
1172                 talloc_free(error_string);
1173
1174                 return NT_STATUS_ACCESS_DENIED;
1175         }
1176
1177         return NT_STATUS_OK;
1178 }
1179
1180 /* Try to figure out what features we actually got on the connection */
1181 static bool gensec_gssapi_have_feature(struct gensec_security *gensec_security,
1182                                        uint32_t feature)
1183 {
1184         struct gensec_gssapi_state *gensec_gssapi_state
1185                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1186         if (feature & GENSEC_FEATURE_SIGN) {
1187                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1188                 if (gensec_gssapi_state->sasl
1189                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1190                         return ((gensec_gssapi_state->sasl_protection & NEG_SIGN)
1191                                 && (gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG));
1192                 }
1193                 return gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG;
1194         }
1195         if (feature & GENSEC_FEATURE_SEAL) {
1196                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1197                 if (gensec_gssapi_state->sasl
1198                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1199                         return ((gensec_gssapi_state->sasl_protection & NEG_SEAL)
1200                                  && (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG));
1201                 }
1202                 return gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG;
1203         }
1204         if (feature & GENSEC_FEATURE_SESSION_KEY) {
1205                 /* Only for GSSAPI/Krb5 */
1206                 if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
1207                         return true;
1208                 }
1209         }
1210         if (feature & GENSEC_FEATURE_DCE_STYLE) {
1211                 return gensec_gssapi_state->gss_got_flags & GSS_C_DCE_STYLE;
1212         }
1213         if (feature & GENSEC_FEATURE_NEW_SPNEGO) {
1214                 NTSTATUS status;
1215                 uint32_t keytype;
1216
1217                 if (!(gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG)) {
1218                         return false;
1219                 }
1220
1221                 if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "force_new_spnego", false)) {
1222                         return true;
1223                 }
1224                 if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "disable_new_spnego", false)) {
1225                         return false;
1226                 }
1227
1228                 status = gssapi_get_session_key(gensec_gssapi_state,
1229                                                 gensec_gssapi_state->gssapi_context, NULL, &keytype);
1230                 /*
1231                  * We should do a proper sig on the mechListMic unless
1232                  * we know we have to be backwards compatible with
1233                  * earlier windows versions.
1234                  *
1235                  * Negotiating a non-krb5
1236                  * mech for example should be regarded as having
1237                  * NEW_SPNEGO
1238                  */
1239                 if (NT_STATUS_IS_OK(status)) {
1240                         switch (keytype) {
1241                         case ENCTYPE_DES_CBC_CRC:
1242                         case ENCTYPE_DES_CBC_MD5:
1243                         case ENCTYPE_ARCFOUR_HMAC:
1244                         case ENCTYPE_DES3_CBC_SHA1:
1245                                 return false;
1246                         }
1247                 }
1248                 return true;
1249         }
1250         /* We can always do async (rather than strict request/reply) packets.  */
1251         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1252                 return true;
1253         }
1254         return false;
1255 }
1256
1257 /*
1258  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1259  * (for encrypting some passwords).
1260  *
1261  * This breaks all the abstractions, but what do you expect...
1262  */
1263 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1264                                           TALLOC_CTX *mem_ctx,
1265                                           DATA_BLOB *session_key)
1266 {
1267         struct gensec_gssapi_state *gensec_gssapi_state
1268                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1269         return gssapi_get_session_key(mem_ctx, gensec_gssapi_state->gssapi_context, session_key, NULL);
1270 }
1271
1272 /* Get some basic (and authorization) information about the user on
1273  * this session.  This uses either the PAC (if present) or a local
1274  * database lookup */
1275 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1276                                            TALLOC_CTX *mem_ctx,
1277                                            struct auth_session_info **_session_info)
1278 {
1279         NTSTATUS nt_status;
1280         TALLOC_CTX *tmp_ctx;
1281         struct gensec_gssapi_state *gensec_gssapi_state
1282                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1283         struct auth_session_info *session_info = NULL;
1284         OM_uint32 maj_stat, min_stat;
1285         DATA_BLOB pac_blob, *pac_blob_ptr = NULL;
1286
1287         gss_buffer_desc name_token;
1288         char *principal_string;
1289
1290         tmp_ctx = talloc_named(mem_ctx, 0, "gensec_gssapi_session_info context");
1291         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
1292
1293         maj_stat = gss_display_name (&min_stat,
1294                                      gensec_gssapi_state->client_name,
1295                                      &name_token,
1296                                      NULL);
1297         if (GSS_ERROR(maj_stat)) {
1298                 DEBUG(1, ("GSS display_name failed: %s\n",
1299                           gssapi_error_string(tmp_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1300                 talloc_free(tmp_ctx);
1301                 return NT_STATUS_FOOBAR;
1302         }
1303
1304         principal_string = talloc_strndup(tmp_ctx,
1305                                           (const char *)name_token.value,
1306                                           name_token.length);
1307
1308         gss_release_buffer(&min_stat, &name_token);
1309
1310         if (!principal_string) {
1311                 talloc_free(tmp_ctx);
1312                 return NT_STATUS_NO_MEMORY;
1313         }
1314
1315         nt_status = gssapi_obtain_pac_blob(tmp_ctx,  gensec_gssapi_state->gssapi_context,
1316                                            gensec_gssapi_state->client_name,
1317                                            &pac_blob);
1318
1319         /* IF we have the PAC - otherwise we need to get this
1320          * data from elsewere - local ldb, or (TODO) lookup of some
1321          * kind...
1322          */
1323         if (NT_STATUS_IS_OK(nt_status)) {
1324                 pac_blob_ptr = &pac_blob;
1325         }
1326         nt_status = gensec_generate_session_info_pac(tmp_ctx,
1327                                                      gensec_security,
1328                                                      gensec_gssapi_state->smb_krb5_context,
1329                                                      pac_blob_ptr, principal_string,
1330                                                      gensec_get_remote_address(gensec_security),
1331                                                      &session_info);
1332         if (!NT_STATUS_IS_OK(nt_status)) {
1333                 talloc_free(tmp_ctx);
1334                 return nt_status;
1335         }
1336
1337         nt_status = gensec_gssapi_session_key(gensec_security, session_info, &session_info->session_key);
1338         if (!NT_STATUS_IS_OK(nt_status)) {
1339                 talloc_free(tmp_ctx);
1340                 return nt_status;
1341         }
1342
1343         if (!(gensec_gssapi_state->gss_got_flags & GSS_C_DELEG_FLAG)) {
1344                 DEBUG(10, ("gensec_gssapi: NO delegated credentials supplied by client\n"));
1345         } else {
1346                 krb5_error_code ret;
1347                 const char *error_string;
1348
1349                 DEBUG(10, ("gensec_gssapi: delegated credentials supplied by client\n"));
1350                 session_info->credentials = cli_credentials_init(session_info);
1351                 if (!session_info->credentials) {
1352                         talloc_free(tmp_ctx);
1353                         return NT_STATUS_NO_MEMORY;
1354                 }
1355
1356                 cli_credentials_set_conf(session_info->credentials, gensec_security->settings->lp_ctx);
1357                 /* Just so we don't segfault trying to get at a username */
1358                 cli_credentials_set_anonymous(session_info->credentials);
1359
1360                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1361                                                            gensec_security->settings->lp_ctx,
1362                                                            gensec_gssapi_state->delegated_cred_handle,
1363                                                            CRED_SPECIFIED, &error_string);
1364                 if (ret) {
1365                         talloc_free(tmp_ctx);
1366                         DEBUG(2,("Failed to get gss creds: %s\n", error_string));
1367                         return NT_STATUS_NO_MEMORY;
1368                 }
1369
1370                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1371                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1372
1373                 /* It has been taken from this place... */
1374                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1375         }
1376         *_session_info = talloc_steal(mem_ctx, session_info);
1377         talloc_free(tmp_ctx);
1378
1379         return NT_STATUS_OK;
1380 }
1381
1382 static size_t gensec_gssapi_sig_size(struct gensec_security *gensec_security, size_t data_size)
1383 {
1384         struct gensec_gssapi_state *gensec_gssapi_state
1385                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1386         NTSTATUS status;
1387
1388         if (gensec_gssapi_state->sig_size) {
1389                 return gensec_gssapi_state->sig_size;
1390         }
1391
1392         if (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG) {
1393                 gensec_gssapi_state->sig_size = 45;
1394         } else {
1395                 gensec_gssapi_state->sig_size = 37;
1396         }
1397
1398         status = gensec_gssapi_init_lucid(gensec_gssapi_state);
1399         if (!NT_STATUS_IS_OK(status)) {
1400                 return gensec_gssapi_state->sig_size;
1401         }
1402
1403         if (gensec_gssapi_state->lucid->protocol == 1) {
1404                 if (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG) {
1405                         /*
1406                          * TODO: windows uses 76 here, but we don't know
1407                          *       gss_wrap works with aes keys yet
1408                          */
1409                         gensec_gssapi_state->sig_size = 76;
1410                 } else {
1411                         gensec_gssapi_state->sig_size = 28;
1412                 }
1413         } else if (gensec_gssapi_state->lucid->protocol == 0) {
1414                 switch (gensec_gssapi_state->lucid->rfc1964_kd.ctx_key.type) {
1415                 case KEYTYPE_DES:
1416                 case KEYTYPE_ARCFOUR:
1417                 case KEYTYPE_ARCFOUR_56:
1418                         if (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG) {
1419                                 gensec_gssapi_state->sig_size = 45;
1420                         } else {
1421                                 gensec_gssapi_state->sig_size = 37;
1422                         }
1423                         break;
1424                 case KEYTYPE_DES3:
1425                         if (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG) {
1426                                 gensec_gssapi_state->sig_size = 57;
1427                         } else {
1428                                 gensec_gssapi_state->sig_size = 49;
1429                         }
1430                         break;
1431                 }
1432         }
1433
1434         return gensec_gssapi_state->sig_size;
1435 }
1436
1437 static const char *gensec_gssapi_krb5_oids[] = {
1438         GENSEC_OID_KERBEROS5_OLD,
1439         GENSEC_OID_KERBEROS5,
1440         NULL
1441 };
1442
1443 static const char *gensec_gssapi_spnego_oids[] = {
1444         GENSEC_OID_SPNEGO,
1445         NULL
1446 };
1447
1448 /* As a server, this could in theory accept any GSSAPI mech */
1449 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1450         .name           = "gssapi_spnego",
1451         .sasl_name      = "GSS-SPNEGO",
1452         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1453         .oid            = gensec_gssapi_spnego_oids,
1454         .client_start   = gensec_gssapi_client_start,
1455         .server_start   = gensec_gssapi_server_start,
1456         .magic          = gensec_magic_check_krb5_oid,
1457         .update         = gensec_gssapi_update,
1458         .session_key    = gensec_gssapi_session_key,
1459         .session_info   = gensec_gssapi_session_info,
1460         .sign_packet    = gensec_gssapi_sign_packet,
1461         .check_packet   = gensec_gssapi_check_packet,
1462         .seal_packet    = gensec_gssapi_seal_packet,
1463         .unseal_packet  = gensec_gssapi_unseal_packet,
1464         .wrap           = gensec_gssapi_wrap,
1465         .unwrap         = gensec_gssapi_unwrap,
1466         .have_feature   = gensec_gssapi_have_feature,
1467         .enabled        = false,
1468         .kerberos       = true,
1469         .priority       = GENSEC_GSSAPI
1470 };
1471
1472 /* As a server, this could in theory accept any GSSAPI mech */
1473 static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
1474         .name           = "gssapi_krb5",
1475         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1476         .oid            = gensec_gssapi_krb5_oids,
1477         .client_start   = gensec_gssapi_client_start,
1478         .server_start   = gensec_gssapi_server_start,
1479         .magic          = gensec_magic_check_krb5_oid,
1480         .update         = gensec_gssapi_update,
1481         .session_key    = gensec_gssapi_session_key,
1482         .session_info   = gensec_gssapi_session_info,
1483         .sig_size       = gensec_gssapi_sig_size,
1484         .sign_packet    = gensec_gssapi_sign_packet,
1485         .check_packet   = gensec_gssapi_check_packet,
1486         .seal_packet    = gensec_gssapi_seal_packet,
1487         .unseal_packet  = gensec_gssapi_unseal_packet,
1488         .wrap           = gensec_gssapi_wrap,
1489         .unwrap         = gensec_gssapi_unwrap,
1490         .have_feature   = gensec_gssapi_have_feature,
1491         .enabled        = true,
1492         .kerberos       = true,
1493         .priority       = GENSEC_GSSAPI
1494 };
1495
1496 /* As a server, this could in theory accept any GSSAPI mech */
1497 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1498         .name             = "gssapi_krb5_sasl",
1499         .sasl_name        = "GSSAPI",
1500         .client_start     = gensec_gssapi_sasl_client_start,
1501         .server_start     = gensec_gssapi_sasl_server_start,
1502         .update           = gensec_gssapi_update,
1503         .session_key      = gensec_gssapi_session_key,
1504         .session_info     = gensec_gssapi_session_info,
1505         .max_input_size   = gensec_gssapi_max_input_size,
1506         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1507         .wrap             = gensec_gssapi_wrap,
1508         .unwrap           = gensec_gssapi_unwrap,
1509         .have_feature     = gensec_gssapi_have_feature,
1510         .enabled          = true,
1511         .kerberos         = true,
1512         .priority         = GENSEC_GSSAPI
1513 };
1514
1515 _PUBLIC_ NTSTATUS gensec_gssapi_init(void)
1516 {
1517         NTSTATUS ret;
1518
1519         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1520         if (!NT_STATUS_IS_OK(ret)) {
1521                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1522                         gensec_gssapi_spnego_security_ops.name));
1523                 return ret;
1524         }
1525
1526         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1527         if (!NT_STATUS_IS_OK(ret)) {
1528                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1529                         gensec_gssapi_krb5_security_ops.name));
1530                 return ret;
1531         }
1532
1533         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1534         if (!NT_STATUS_IS_OK(ret)) {
1535                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1536                         gensec_gssapi_sasl_krb5_security_ops.name));
1537                 return ret;
1538         }
1539
1540         return ret;
1541 }