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 "auth/kerberos/kerberos.h"
  28 #include "librpc/gen_ndr/krb5pac.h"
  29 #include "auth/auth.h"
  30 #include <ldb.h>
  31 #include "auth/auth_sam.h"
  32 #include "librpc/rpc/dcerpc.h"
  33 #include "auth/credentials/credentials.h"
  34 #include "auth/credentials/credentials_krb5.h"
  35 #include "auth/gensec/gensec.h"
  36 #include "auth/gensec/gensec_proto.h"
  37 #include "auth/gensec/gensec_toplevel_proto.h"
  38 #include "param/param.h"
  39 #include "auth/session_proto.h"
  40 #include <gssapi/gssapi.h>
  41 #include <gssapi/gssapi_krb5.h>
  42 #include <gssapi/gssapi_spnego.h>
  43 #include "gensec_gssapi.h"
  44 #include "lib/util/util_net.h"
  45
  46 _PUBLIC_ NTSTATUS gensec_gssapi_init(void);
  47
  48 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security);
  49 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security);
  50
  51 static int gensec_gssapi_destructor(struct gensec_gssapi_state *gensec_gssapi_state)
  52 {
  53         OM_uint32 maj_stat, min_stat;
  54
  55         if (gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
  56                 maj_stat = gss_release_cred(&min_stat,
  57                                             &gensec_gssapi_state->delegated_cred_handle);
  58         }
  59
  60         if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
  61                 maj_stat = gss_delete_sec_context (&min_stat,
  62                                                    &gensec_gssapi_state->gssapi_context,
  63                                                    GSS_C_NO_BUFFER);
  64         }
  65
  66         if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
  67                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->server_name);
  68         }
  69         if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
  70                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->client_name);
  71         }
  72
  73         if (gensec_gssapi_state->lucid) {
  74                 gss_krb5_free_lucid_sec_context(&min_stat, gensec_gssapi_state->lucid);
  75         }
  76
  77         return 0;
  78 }
  79
  80 static NTSTATUS gensec_gssapi_init_lucid(struct gensec_gssapi_state *gensec_gssapi_state)
  81 {
  82         OM_uint32 maj_stat, min_stat;
  83
  84         if (gensec_gssapi_state->lucid) {
  85                 return NT_STATUS_OK;
  86         }
  87
  88         maj_stat = gss_krb5_export_lucid_sec_context(&min_stat,
  89                                                      &gensec_gssapi_state->gssapi_context,
  90                                                      1,
  91                                                      (void **)&gensec_gssapi_state->lucid);
  92         if (maj_stat != GSS_S_COMPLETE) {
  93                 DEBUG(0,("gensec_gssapi_init_lucid: %s\n",
  94                         gssapi_error_string(gensec_gssapi_state,
  95                                             maj_stat, min_stat,
  96                                             gensec_gssapi_state->gss_oid)));
  97                 return NT_STATUS_INTERNAL_ERROR;
  98         }
  99
 100         if (gensec_gssapi_state->lucid->version != 1) {
 101                 DEBUG(0,("gensec_gssapi_init_lucid: lucid version[%d] != 1\n",
 102                         gensec_gssapi_state->lucid->version));
 103                 gss_krb5_free_lucid_sec_context(&min_stat, gensec_gssapi_state->lucid);
 104                 gensec_gssapi_state->lucid = NULL;
 105                 return NT_STATUS_INTERNAL_ERROR;
 106         }
 107
 108         return NT_STATUS_OK;
 109 }
 110
 111 static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 112 {
 113         struct gensec_gssapi_state *gensec_gssapi_state;
 114         krb5_error_code ret;
 115         const char *realm;
 116
 117         gensec_gssapi_state = talloc_zero(gensec_security, struct gensec_gssapi_state);
 118         if (!gensec_gssapi_state) {
 119                 return NT_STATUS_NO_MEMORY;
 120         }
 121
 122         gensec_security->private_data = gensec_gssapi_state;
 123
 124         gensec_gssapi_state->gssapi_context = GSS_C_NO_CONTEXT;
 125
 126         /* TODO: Fill in channel bindings */
 127         gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
 128
 129         gensec_gssapi_state->server_name = GSS_C_NO_NAME;
 130         gensec_gssapi_state->client_name = GSS_C_NO_NAME;
 131
 132         gensec_gssapi_state->gss_want_flags = 0;
 133
 134         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation_by_kdc_policy", true)) {
 135                 gensec_gssapi_state->gss_want_flags |= GSS_C_DELEG_POLICY_FLAG;
 136         }
 137         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "mutual", true)) {
 138                 gensec_gssapi_state->gss_want_flags |= GSS_C_MUTUAL_FLAG;
 139         }
 140         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation", true)) {
 141                 gensec_gssapi_state->gss_want_flags |= GSS_C_DELEG_FLAG;
 142         }
 143         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "replay", true)) {
 144                 gensec_gssapi_state->gss_want_flags |= GSS_C_REPLAY_FLAG;
 145         }
 146         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "sequence", true)) {
 147                 gensec_gssapi_state->gss_want_flags |= GSS_C_SEQUENCE_FLAG;
 148         }
 149
 150         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 151                 gensec_gssapi_state->gss_want_flags |= GSS_C_INTEG_FLAG;
 152         }
 153         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 154                 gensec_gssapi_state->gss_want_flags |= GSS_C_INTEG_FLAG;
 155                 gensec_gssapi_state->gss_want_flags |= GSS_C_CONF_FLAG;
 156         }
 157         if (gensec_security->want_features & GENSEC_FEATURE_DCE_STYLE) {
 158                 gensec_gssapi_state->gss_want_flags |= GSS_C_DCE_STYLE;
 159         }
 160
 161         gensec_gssapi_state->gss_got_flags = 0;
 162
 163         switch (gensec_security->ops->auth_type) {
 164         case DCERPC_AUTH_TYPE_SPNEGO:
 165                 gensec_gssapi_state->gss_oid = gss_mech_spnego;
 166                 break;
 167         case DCERPC_AUTH_TYPE_KRB5:
 168         default:
 169                 gensec_gssapi_state->gss_oid = gss_mech_krb5;
 170                 break;
 171         }
 172
 173         ret = smb_krb5_init_context(gensec_gssapi_state,
 174                                     NULL,
 175                                     gensec_security->settings->lp_ctx,
 176                                     &gensec_gssapi_state->smb_krb5_context);
 177         if (ret) {
 178                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n",
 179                          error_message(ret)));
 180                 talloc_free(gensec_gssapi_state);
 181                 return NT_STATUS_INTERNAL_ERROR;
 182         }
 183
 184         gensec_gssapi_state->client_cred = NULL;
 185         gensec_gssapi_state->server_cred = NULL;
 186
 187         gensec_gssapi_state->lucid = NULL;
 188
 189         gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 190
 191         gensec_gssapi_state->sasl = false;
 192         gensec_gssapi_state->sasl_state = STAGE_GSS_NEG;
 193         gensec_gssapi_state->sasl_protection = 0;
 194
 195         gensec_gssapi_state->max_wrap_buf_size
 196                 = gensec_setting_int(gensec_security->settings, "gensec_gssapi", "max wrap buf size", 65536);
 197         gensec_gssapi_state->gss_exchange_count = 0;
 198         gensec_gssapi_state->sig_size = 0;
 199
 200         talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 201
 202         realm = lpcfg_realm(gensec_security->settings->lp_ctx);
 203         if (realm != NULL) {
 204                 ret = gsskrb5_set_default_realm(realm);
 205                 if (ret) {
 206                         DEBUG(1,("gensec_krb5_start: gsskrb5_set_default_realm failed\n"));
 207                         talloc_free(gensec_gssapi_state);
 208                         return NT_STATUS_INTERNAL_ERROR;
 209                 }
 210         }
 211
 212         /* don't do DNS lookups of any kind, it might/will fail for a netbios name */
 213         ret = gsskrb5_set_dns_canonicalize(gensec_setting_bool(gensec_security->settings, "krb5", "set_dns_canonicalize", false));
 214         if (ret) {
 215                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_dns_canonicalize failed\n"));
 216                 talloc_free(gensec_gssapi_state);
 217                 return NT_STATUS_INTERNAL_ERROR;
 218         }
 219
 220         return NT_STATUS_OK;
 221 }
 222
 223 static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
 224 {
 225         NTSTATUS nt_status;
 226         int ret;
 227         struct gensec_gssapi_state *gensec_gssapi_state;
 228         struct cli_credentials *machine_account;
 229         struct gssapi_creds_container *gcc;
 230
 231         nt_status = gensec_gssapi_start(gensec_security);
 232         if (!NT_STATUS_IS_OK(nt_status)) {
 233                 return nt_status;
 234         }
 235
 236         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 237
 238         machine_account = gensec_get_credentials(gensec_security);
 239
 240         if (!machine_account) {
 241                 DEBUG(3, ("No machine account credentials specified\n"));
 242                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 243         } else {
 244                 ret = cli_credentials_get_server_gss_creds(machine_account,
 245                                                            gensec_security->settings->lp_ctx, &gcc);
 246                 if (ret) {
 247                         DEBUG(1, ("Aquiring acceptor credentials failed: %s\n",
 248                                   error_message(ret)));
 249                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 250                 }
 251         }
 252
 253         gensec_gssapi_state->server_cred = gcc;
 254         return NT_STATUS_OK;
 255
 256 }
 257
 258 static NTSTATUS gensec_gssapi_sasl_server_start(struct gensec_security *gensec_security)
 259 {
 260         NTSTATUS nt_status;
 261         struct gensec_gssapi_state *gensec_gssapi_state;
 262         nt_status = gensec_gssapi_server_start(gensec_security);
 263
 264         if (NT_STATUS_IS_OK(nt_status)) {
 265                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 266                 gensec_gssapi_state->sasl = true;
 267         }
 268         return nt_status;
 269 }
 270
 271 static NTSTATUS gensec_gssapi_client_creds(struct gensec_security *gensec_security,
 272                                            struct tevent_context *ev)
 273 {
 274         struct gensec_gssapi_state *gensec_gssapi_state;
 275         struct gssapi_creds_container *gcc;
 276         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 277         const char *error_string;
 278         int ret;
 279
 280         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 281
 282         /* Only run this the first time the update() call is made */
 283         if (gensec_gssapi_state->client_cred) {
 284                 return NT_STATUS_OK;
 285         }
 286
 287         ret = cli_credentials_get_client_gss_creds(creds,
 288                                                    ev,
 289                                                    gensec_security->settings->lp_ctx, &gcc, &error_string);
 290         switch (ret) {
 291         case 0:
 292                 break;
 293         case EINVAL:
 294                 DEBUG(3, ("Cannot obtain client GSS credentials we need to contact %s : %s\n", gensec_gssapi_state->target_principal, error_string));
 295                 return NT_STATUS_INVALID_PARAMETER;
 296         case KRB5KDC_ERR_PREAUTH_FAILED:
 297         case KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN:
 298                 DEBUG(1, ("Wrong username or password: %s\n", error_string));
 299                 return NT_STATUS_LOGON_FAILURE;
 300         case KRB5_KDC_UNREACH:
 301                 DEBUG(3, ("Cannot reach a KDC we require to contact %s : %s\n", gensec_gssapi_state->target_principal, error_string));
 302                 return NT_STATUS_NO_LOGON_SERVERS;
 303         case KRB5_CC_NOTFOUND:
 304         case KRB5_CC_END:
 305                 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));
 306                 return NT_STATUS_TIME_DIFFERENCE_AT_DC;
 307         default:
 308                 DEBUG(1, ("Aquiring initiator credentials failed: %s\n", error_string));
 309                 return NT_STATUS_UNSUCCESSFUL;
 310         }
 311
 312         gensec_gssapi_state->client_cred = gcc;
 313         if (!talloc_reference(gensec_gssapi_state, gcc)) {
 314                 return NT_STATUS_NO_MEMORY;
 315         }
 316
 317         return NT_STATUS_OK;
 318 }
 319
 320 static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
 321 {
 322         struct gensec_gssapi_state *gensec_gssapi_state;
 323         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 324         NTSTATUS nt_status;
 325         gss_buffer_desc name_token;
 326         gss_OID name_type;
 327         OM_uint32 maj_stat, min_stat;
 328         const char *hostname = gensec_get_target_hostname(gensec_security);
 329
 330         if (!hostname) {
 331                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 332                 return NT_STATUS_INVALID_PARAMETER;
 333         }
 334         if (is_ipaddress(hostname)) {
 335                 DEBUG(2, ("Cannot do GSSAPI to an IP address\n"));
 336                 return NT_STATUS_INVALID_PARAMETER;
 337         }
 338         if (strcmp(hostname, "localhost") == 0) {
 339                 DEBUG(2, ("GSSAPI to 'localhost' does not make sense\n"));
 340                 return NT_STATUS_INVALID_PARAMETER;
 341         }
 342
 343         nt_status = gensec_gssapi_start(gensec_security);
 344         if (!NT_STATUS_IS_OK(nt_status)) {
 345                 return nt_status;
 346         }
 347
 348         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 349
 350         if (cli_credentials_get_impersonate_principal(creds)) {
 351                 gensec_gssapi_state->gss_want_flags &= ~(GSS_C_DELEG_FLAG|GSS_C_DELEG_POLICY_FLAG);
 352         }
 353
 354         gensec_gssapi_state->target_principal = gensec_get_target_principal(gensec_security);
 355         if (gensec_gssapi_state->target_principal) {
 356                 name_type = GSS_C_NULL_OID;
 357         } else {
 358                 gensec_gssapi_state->target_principal = talloc_asprintf(gensec_gssapi_state, "%s/%s@%s",
 359                                             gensec_get_target_service(gensec_security),
 360                                             hostname, lpcfg_realm(gensec_security->settings->lp_ctx));
 361
 362                 name_type = GSS_C_NT_USER_NAME;
 363         }
 364         name_token.value  = discard_const_p(uint8_t, gensec_gssapi_state->target_principal);
 365         name_token.length = strlen(gensec_gssapi_state->target_principal);
 366
 367
 368         maj_stat = gss_import_name (&min_stat,
 369                                     &name_token,
 370                                     name_type,
 371                                     &gensec_gssapi_state->server_name);
 372         if (maj_stat) {
 373                 DEBUG(2, ("GSS Import name of %s failed: %s\n",
 374                           (char *)name_token.value,
 375                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 376                 return NT_STATUS_INVALID_PARAMETER;
 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  * Next state function for the GSSAPI GENSEC mechanism
 398  *
 399  * @param gensec_gssapi_state GSSAPI State
 400  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 401  * @param in The request, as a DATA_BLOB
 402  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 403  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 404  *                or NT_STATUS_OK if the user is authenticated.
 405  */
 406
 407 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 408                                      TALLOC_CTX *out_mem_ctx,
 409                                      struct tevent_context *ev,
 410                                      const DATA_BLOB in, DATA_BLOB *out)
 411 {
 412         struct gensec_gssapi_state *gensec_gssapi_state
 413                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 414         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 415         OM_uint32 maj_stat, min_stat;
 416         OM_uint32 min_stat2;
 417         gss_buffer_desc input_token, output_token;
 418         gss_OID gss_oid_p = NULL;
 419         input_token.length = in.length;
 420         input_token.value = in.data;
 421
 422         switch (gensec_gssapi_state->sasl_state) {
 423         case STAGE_GSS_NEG:
 424         {
 425                 switch (gensec_security->gensec_role) {
 426                 case GENSEC_CLIENT:
 427                 {
 428                         struct gsskrb5_send_to_kdc send_to_kdc;
 429                         krb5_error_code ret;
 430
 431                         nt_status = gensec_gssapi_client_creds(gensec_security, ev);
 432                         if (!NT_STATUS_IS_OK(nt_status)) {
 433                                 return nt_status;
 434                         }
 435
 436                         send_to_kdc.func = smb_krb5_send_and_recv_func;
 437                         send_to_kdc.ptr = ev;
 438
 439                         min_stat = gsskrb5_set_send_to_kdc(&send_to_kdc);
 440                         if (min_stat) {
 441                                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 442                                 return NT_STATUS_INTERNAL_ERROR;
 443                         }
 444
 445                         maj_stat = gss_init_sec_context(&min_stat,
 446                                                         gensec_gssapi_state->client_cred->creds,
 447                                                         &gensec_gssapi_state->gssapi_context,
 448                                                         gensec_gssapi_state->server_name,
 449                                                         gensec_gssapi_state->gss_oid,
 450                                                         gensec_gssapi_state->gss_want_flags,
 451                                                         0,
 452                                                         gensec_gssapi_state->input_chan_bindings,
 453                                                         &input_token,
 454                                                         &gss_oid_p,
 455                                                         &output_token,
 456                                                         &gensec_gssapi_state->gss_got_flags, /* ret flags */
 457                                                         NULL);
 458                         if (gss_oid_p) {
 459                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 460                         }
 461
 462                         send_to_kdc.func = smb_krb5_send_and_recv_func;
 463                         send_to_kdc.ptr = NULL;
 464
 465                         ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
 466                         if (ret) {
 467                                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 468                                 return NT_STATUS_INTERNAL_ERROR;
 469                         }
 470
 471                         break;
 472                 }
 473                 case GENSEC_SERVER:
 474                 {
 475                         maj_stat = gss_accept_sec_context(&min_stat,
 476                                                           &gensec_gssapi_state->gssapi_context,
 477                                                           gensec_gssapi_state->server_cred->creds,
 478                                                           &input_token,
 479                                                           gensec_gssapi_state->input_chan_bindings,
 480                                                           &gensec_gssapi_state->client_name,
 481                                                           &gss_oid_p,
 482                                                           &output_token,
 483                                                           &gensec_gssapi_state->gss_got_flags,
 484                                                           NULL,
 485                                                           &gensec_gssapi_state->delegated_cred_handle);
 486                         if (gss_oid_p) {
 487                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 488                         }
 489                         break;
 490                 }
 491                 default:
 492                         return NT_STATUS_INVALID_PARAMETER;
 493
 494                 }
 495
 496                 gensec_gssapi_state->gss_exchange_count++;
 497
 498                 if (maj_stat == GSS_S_COMPLETE) {
 499                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 500                         gss_release_buffer(&min_stat2, &output_token);
 501
 502                         if (gensec_gssapi_state->gss_got_flags & GSS_C_DELEG_FLAG) {
 503                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 504                         } else {
 505                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 506                         }
 507
 508                         /* We may have been invoked as SASL, so there
 509                          * is more work to do */
 510                         if (gensec_gssapi_state->sasl) {
 511                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 512                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 513                         } else {
 514                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 515
 516                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 517                                         DEBUG(5, ("GSSAPI Connection will be cryptographically sealed\n"));
 518                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 519                                         DEBUG(5, ("GSSAPI Connection will be cryptographically signed\n"));
 520                                 } else {
 521                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 522                                 }
 523
 524                                 return NT_STATUS_OK;
 525                         }
 526                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 527                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 528                         gss_release_buffer(&min_stat2, &output_token);
 529
 530                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 531                 } else if (maj_stat == GSS_S_CONTEXT_EXPIRED) {
 532                         gss_cred_id_t creds;
 533                         gss_name_t name;
 534                         gss_buffer_desc buffer;
 535                         OM_uint32 lifetime = 0;
 536                         gss_cred_usage_t usage;
 537                         const char *role = NULL;
 538                         DEBUG(0, ("GSS %s Update(krb5)(%d) Update failed, credentials expired during GSSAPI handshake!\n",
 539                                   role,
 540                                   gensec_gssapi_state->gss_exchange_count));
 541
 542
 543                         switch (gensec_security->gensec_role) {
 544                         case GENSEC_CLIENT:
 545                                 creds = gensec_gssapi_state->client_cred->creds;
 546                                 role = "client";
 547                         case GENSEC_SERVER:
 548                                 creds = gensec_gssapi_state->server_cred->creds;
 549                                 role = "server";
 550                         }
 551
 552                         maj_stat = gss_inquire_cred(&min_stat,
 553                                                     creds,
 554                                                     &name, &lifetime, &usage, NULL);
 555
 556                         if (maj_stat == GSS_S_COMPLETE) {
 557                                 const char *usage_string;
 558                                 switch (usage) {
 559                                 case GSS_C_BOTH:
 560                                         usage_string = "GSS_C_BOTH";
 561                                         break;
 562                                 case GSS_C_ACCEPT:
 563                                         usage_string = "GSS_C_ACCEPT";
 564                                         break;
 565                                 case GSS_C_INITIATE:
 566                                         usage_string = "GSS_C_INITIATE";
 567                                         break;
 568                                 }
 569                                 maj_stat = gss_display_name(&min_stat, name, &buffer, NULL);
 570                                 if (maj_stat) {
 571                                         buffer.value = NULL;
 572                                         buffer.length = 0;
 573                                 }
 574                                 if (lifetime > 0) {
 575                                         DEBUG(0, ("GSSAPI gss_inquire_cred indicates expiry of %*.*s in %u sec for %s\n",
 576                                                   (int)buffer.length, (int)buffer.length, (char *)buffer.value,
 577                                                   lifetime, usage_string));
 578                                 } else {
 579                                         DEBUG(0, ("GSSAPI gss_inquire_cred indicates %*.*s has already expired for %s\n",
 580                                                   (int)buffer.length, (int)buffer.length, (char *)buffer.value,
 581                                                   usage_string));
 582                                 }
 583                                 gss_release_buffer(&min_stat, &buffer);
 584                                 gss_release_name(&min_stat, &name);
 585                         } else if (maj_stat != GSS_S_COMPLETE) {
 586                                 DEBUG(0, ("inquiry of credential lifefime via GSSAPI gss_inquire_cred failed: %s\n",
 587                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 588                         }
 589                         return NT_STATUS_INVALID_PARAMETER;
 590                 } else if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
 591                         switch (min_stat) {
 592                         case KRB5KRB_AP_ERR_TKT_NYV:
 593                                 DEBUG(1, ("Error with ticket to contact %s: possible clock skew between us and the KDC or target server: %s\n",
 594                                           gensec_gssapi_state->target_principal,
 595                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 596                                 return NT_STATUS_TIME_DIFFERENCE_AT_DC; /* Make SPNEGO ignore us, we can't go any further here */
 597                         case KRB5KRB_AP_ERR_TKT_EXPIRED:
 598                                 DEBUG(1, ("Error with ticket to contact %s: ticket is expired, possible clock skew between us and the KDC or target server: %s\n",
 599                                           gensec_gssapi_state->target_principal,
 600                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 601                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 602                         case KRB5_KDC_UNREACH:
 603                                 DEBUG(3, ("Cannot reach a KDC we require in order to obtain a ticetk to %s: %s\n",
 604                                           gensec_gssapi_state->target_principal,
 605                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 606                                 return NT_STATUS_NO_LOGON_SERVERS; /* Make SPNEGO ignore us, we can't go any further here */
 607                         case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 608                                 DEBUG(3, ("Server %s is not registered with our KDC: %s\n",
 609                                           gensec_gssapi_state->target_principal,
 610                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 611                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 612                         case KRB5KRB_AP_ERR_MSG_TYPE:
 613                                 /* garbage input, possibly from the auto-mech detection */
 614                                 return NT_STATUS_INVALID_PARAMETER;
 615                         default:
 616                                 DEBUG(1, ("GSS %s Update(krb5)(%d) Update failed: %s\n",
 617                                           gensec_security->gensec_role == GENSEC_CLIENT ? "client" : "server",
 618                                           gensec_gssapi_state->gss_exchange_count,
 619                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 620                                 return nt_status;
 621                         }
 622                 } else {
 623                         DEBUG(1, ("GSS %s Update(%d) failed: %s\n",
 624                                   gensec_security->gensec_role == GENSEC_CLIENT ? "client" : "server",
 625                                   gensec_gssapi_state->gss_exchange_count,
 626                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 627                         return nt_status;
 628                 }
 629                 break;
 630         }
 631
 632         /* These last two stages are only done if we were invoked as SASL */
 633         case STAGE_SASL_SSF_NEG:
 634         {
 635                 switch (gensec_security->gensec_role) {
 636                 case GENSEC_CLIENT:
 637                 {
 638                         uint8_t maxlength_proposed[4];
 639                         uint8_t maxlength_accepted[4];
 640                         uint8_t security_supported;
 641                         int conf_state;
 642                         gss_qop_t qop_state;
 643                         input_token.length = in.length;
 644                         input_token.value = in.data;
 645
 646                         /* As a client, we have just send a
 647                          * zero-length blob to the server (after the
 648                          * normal GSSAPI exchange), and it has replied
 649                          * with it's SASL negotiation */
 650
 651                         maj_stat = gss_unwrap(&min_stat,
 652                                               gensec_gssapi_state->gssapi_context,
 653                                               &input_token,
 654                                               &output_token,
 655                                               &conf_state,
 656                                               &qop_state);
 657                         if (GSS_ERROR(maj_stat)) {
 658                                 DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 659                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 660                                 return NT_STATUS_ACCESS_DENIED;
 661                         }
 662
 663                         if (output_token.length < 4) {
 664                                 return NT_STATUS_INVALID_PARAMETER;
 665                         }
 666
 667                         memcpy(maxlength_proposed, output_token.value, 4);
 668                         gss_release_buffer(&min_stat, &output_token);
 669
 670                         /* first byte is the proposed security */
 671                         security_supported = maxlength_proposed[0];
 672                         maxlength_proposed[0] = '\0';
 673
 674                         /* Rest is the proposed max wrap length */
 675                         gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_proposed, 0),
 676                                                                      gensec_gssapi_state->max_wrap_buf_size);
 677                         gensec_gssapi_state->sasl_protection = 0;
 678                         if (security_supported & NEG_SEAL) {
 679                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 680                                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 681                                 }
 682                         }
 683                         if (security_supported & NEG_SIGN) {
 684                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 685                                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 686                                 }
 687                         }
 688                         if (security_supported & NEG_NONE) {
 689                                 gensec_gssapi_state->sasl_protection |= NEG_NONE;
 690                         }
 691                         if (gensec_gssapi_state->sasl_protection == 0) {
 692                                 DEBUG(1, ("Remote server does not support unprotected connections\n"));
 693                                 return NT_STATUS_ACCESS_DENIED;
 694                         }
 695
 696                         /* Send back the negotiated max length */
 697
 698                         RSIVAL(maxlength_accepted, 0, gensec_gssapi_state->max_wrap_buf_size);
 699
 700                         maxlength_accepted[0] = gensec_gssapi_state->sasl_protection;
 701
 702                         input_token.value = maxlength_accepted;
 703                         input_token.length = sizeof(maxlength_accepted);
 704
 705                         maj_stat = gss_wrap(&min_stat,
 706                                             gensec_gssapi_state->gssapi_context,
 707                                             false,
 708                                             GSS_C_QOP_DEFAULT,
 709                                             &input_token,
 710                                             &conf_state,
 711                                             &output_token);
 712                         if (GSS_ERROR(maj_stat)) {
 713                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 714                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 715                                 return NT_STATUS_ACCESS_DENIED;
 716                         }
 717
 718                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 719                         gss_release_buffer(&min_stat, &output_token);
 720
 721                         /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 722                         gensec_gssapi_state->sasl_state = STAGE_DONE;
 723
 724                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 725                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographically sealed\n"));
 726                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 727                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographically signed\n"));
 728                         } else {
 729                                 DEBUG(3, ("SASL/GSSAPI Connection to server will have no cryptographically protection\n"));
 730                         }
 731
 732                         return NT_STATUS_OK;
 733                 }
 734                 case GENSEC_SERVER:
 735                 {
 736                         uint8_t maxlength_proposed[4];
 737                         uint8_t security_supported = 0x0;
 738                         int conf_state;
 739
 740                         /* As a server, we have just been sent a zero-length blob (note this, but it isn't fatal) */
 741                         if (in.length != 0) {
 742                                 DEBUG(1, ("SASL/GSSAPI: client sent non-zero length starting SASL negotiation!\n"));
 743                         }
 744
 745                         /* Give the client some idea what we will support */
 746
 747                         RSIVAL(maxlength_proposed, 0, gensec_gssapi_state->max_wrap_buf_size);
 748                         /* first byte is the proposed security */
 749                         maxlength_proposed[0] = '\0';
 750
 751                         gensec_gssapi_state->sasl_protection = 0;
 752                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 753                                 security_supported |= NEG_SEAL;
 754                         }
 755                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 756                                 security_supported |= NEG_SIGN;
 757                         }
 758                         if (security_supported == 0) {
 759                                 /* If we don't support anything, this must be 0 */
 760                                 RSIVAL(maxlength_proposed, 0, 0x0);
 761                         }
 762
 763                         /* TODO:  We may not wish to support this */
 764                         security_supported |= NEG_NONE;
 765                         maxlength_proposed[0] = security_supported;
 766
 767                         input_token.value = maxlength_proposed;
 768                         input_token.length = sizeof(maxlength_proposed);
 769
 770                         maj_stat = gss_wrap(&min_stat,
 771                                             gensec_gssapi_state->gssapi_context,
 772                                             false,
 773                                             GSS_C_QOP_DEFAULT,
 774                                             &input_token,
 775                                             &conf_state,
 776                                             &output_token);
 777                         if (GSS_ERROR(maj_stat)) {
 778                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 779                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 780                                 return NT_STATUS_ACCESS_DENIED;
 781                         }
 782
 783                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 784                         gss_release_buffer(&min_stat, &output_token);
 785
 786                         gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_ACCEPT;
 787                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 788                 }
 789                 default:
 790                         return NT_STATUS_INVALID_PARAMETER;
 791
 792                 }
 793         }
 794         /* This is s server-only stage */
 795         case STAGE_SASL_SSF_ACCEPT:
 796         {
 797                 uint8_t maxlength_accepted[4];
 798                 uint8_t security_accepted;
 799                 int conf_state;
 800                 gss_qop_t qop_state;
 801                 input_token.length = in.length;
 802                 input_token.value = in.data;
 803
 804                 maj_stat = gss_unwrap(&min_stat,
 805                                       gensec_gssapi_state->gssapi_context,
 806                                       &input_token,
 807                                       &output_token,
 808                                       &conf_state,
 809                                       &qop_state);
 810                 if (GSS_ERROR(maj_stat)) {
 811                         DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 812                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 813                         return NT_STATUS_ACCESS_DENIED;
 814                 }
 815
 816                 if (output_token.length < 4) {
 817                         return NT_STATUS_INVALID_PARAMETER;
 818                 }
 819
 820                 memcpy(maxlength_accepted, output_token.value, 4);
 821                 gss_release_buffer(&min_stat, &output_token);
 822
 823                 /* first byte is the proposed security */
 824                 security_accepted = maxlength_accepted[0];
 825                 maxlength_accepted[0] = '\0';
 826
 827                 /* Rest is the proposed max wrap length */
 828                 gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_accepted, 0),
 829                                                              gensec_gssapi_state->max_wrap_buf_size);
 830
 831                 gensec_gssapi_state->sasl_protection = 0;
 832                 if (security_accepted & NEG_SEAL) {
 833                         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 834                                 DEBUG(1, ("Remote client wanted seal, but gensec refused\n"));
 835                                 return NT_STATUS_ACCESS_DENIED;
 836                         }
 837                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 838                 }
 839                 if (security_accepted & NEG_SIGN) {
 840                         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 841                                 DEBUG(1, ("Remote client wanted sign, but gensec refused\n"));
 842                                 return NT_STATUS_ACCESS_DENIED;
 843                         }
 844                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 845                 }
 846                 if (security_accepted & NEG_NONE) {
 847                         gensec_gssapi_state->sasl_protection |= NEG_NONE;
 848                 }
 849
 850                 /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 851                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 852                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 853                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographically sealed\n"));
 854                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 855                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographically signed\n"));
 856                 } else {
 857                         DEBUG(5, ("SASL/GSSAPI Connection from client will have no cryptographic protection\n"));
 858                 }
 859
 860                 *out = data_blob(NULL, 0);
 861                 return NT_STATUS_OK;
 862         }
 863         default:
 864                 return NT_STATUS_INVALID_PARAMETER;
 865         }
 866 }
 867
 868 static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security,
 869                                    TALLOC_CTX *mem_ctx,
 870                                    const DATA_BLOB *in,
 871                                    DATA_BLOB *out)
 872 {
 873         struct gensec_gssapi_state *gensec_gssapi_state
 874                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 875         OM_uint32 maj_stat, min_stat;
 876         gss_buffer_desc input_token, output_token;
 877         int conf_state;
 878         input_token.length = in->length;
 879         input_token.value = in->data;
 880
 881         maj_stat = gss_wrap(&min_stat,
 882                             gensec_gssapi_state->gssapi_context,
 883                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 884                             GSS_C_QOP_DEFAULT,
 885                             &input_token,
 886                             &conf_state,
 887                             &output_token);
 888         if (GSS_ERROR(maj_stat)) {
 889                 DEBUG(1, ("gensec_gssapi_wrap: GSS Wrap failed: %s\n",
 890                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 891                 return NT_STATUS_ACCESS_DENIED;
 892         }
 893
 894         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 895         gss_release_buffer(&min_stat, &output_token);
 896
 897         if (gensec_gssapi_state->sasl) {
 898                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 899                 if (max_wrapped_size < out->length) {
 900                         DEBUG(1, ("gensec_gssapi_wrap: when wrapped, INPUT data (%u) is grew to be larger than SASL negotiated maximum output size (%u > %u)\n",
 901                                   (unsigned)in->length,
 902                                   (unsigned)out->length,
 903                                   (unsigned int)max_wrapped_size));
 904                         return NT_STATUS_INVALID_PARAMETER;
 905                 }
 906         }
 907
 908         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 909             && !conf_state) {
 910                 return NT_STATUS_ACCESS_DENIED;
 911         }
 912         return NT_STATUS_OK;
 913 }
 914
 915 static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security,
 916                                      TALLOC_CTX *mem_ctx,
 917                                      const DATA_BLOB *in,
 918                                      DATA_BLOB *out)
 919 {
 920         struct gensec_gssapi_state *gensec_gssapi_state
 921                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 922         OM_uint32 maj_stat, min_stat;
 923         gss_buffer_desc input_token, output_token;
 924         int conf_state;
 925         gss_qop_t qop_state;
 926         input_token.length = in->length;
 927         input_token.value = in->data;
 928
 929         if (gensec_gssapi_state->sasl) {
 930                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 931                 if (max_wrapped_size < in->length) {
 932                         DEBUG(1, ("gensec_gssapi_unwrap: WRAPPED data is larger than SASL negotiated maximum size\n"));
 933                         return NT_STATUS_INVALID_PARAMETER;
 934                 }
 935         }
 936
 937         maj_stat = gss_unwrap(&min_stat,
 938                               gensec_gssapi_state->gssapi_context,
 939                               &input_token,
 940                               &output_token,
 941                               &conf_state,
 942                               &qop_state);
 943         if (GSS_ERROR(maj_stat)) {
 944                 DEBUG(1, ("gensec_gssapi_unwrap: GSS UnWrap failed: %s\n",
 945                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 946                 return NT_STATUS_ACCESS_DENIED;
 947         }
 948
 949         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 950         gss_release_buffer(&min_stat, &output_token);
 951
 952         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 953             && !conf_state) {
 954                 return NT_STATUS_ACCESS_DENIED;
 955         }
 956         return NT_STATUS_OK;
 957 }
 958
 959 /* Find out the maximum input size negotiated on this connection */
 960
 961 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security)
 962 {
 963         struct gensec_gssapi_state *gensec_gssapi_state
 964                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 965         OM_uint32 maj_stat, min_stat;
 966         OM_uint32 max_input_size;
 967
 968         maj_stat = gss_wrap_size_limit(&min_stat,
 969                                        gensec_gssapi_state->gssapi_context,
 970                                        gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 971                                        GSS_C_QOP_DEFAULT,
 972                                        gensec_gssapi_state->max_wrap_buf_size,
 973                                        &max_input_size);
 974         if (GSS_ERROR(maj_stat)) {
 975                 TALLOC_CTX *mem_ctx = talloc_new(NULL);
 976                 DEBUG(1, ("gensec_gssapi_max_input_size: determinaing signature size with gss_wrap_size_limit failed: %s\n",
 977                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 978                 talloc_free(mem_ctx);
 979                 return 0;
 980         }
 981
 982         return max_input_size;
 983 }
 984
 985 /* Find out the maximum output size negotiated on this connection */
 986 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security)
 987 {
 988         struct gensec_gssapi_state *gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);;
 989         return gensec_gssapi_state->max_wrap_buf_size;
 990 }
 991
 992 static NTSTATUS gensec_gssapi_seal_packet(struct gensec_security *gensec_security,
 993                                           TALLOC_CTX *mem_ctx,
 994                                           uint8_t *data, size_t length,
 995                                           const uint8_t *whole_pdu, size_t pdu_length,
 996                                           DATA_BLOB *sig)
 997 {
 998         struct gensec_gssapi_state *gensec_gssapi_state
 999                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1000         OM_uint32 maj_stat, min_stat;
1001         gss_buffer_desc input_token, output_token;
1002         int conf_state;
1003         ssize_t sig_length;
1004
1005         input_token.length = length;
1006         input_token.value = data;
1007
1008         maj_stat = gss_wrap(&min_stat,
1009                             gensec_gssapi_state->gssapi_context,
1010                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
1011                             GSS_C_QOP_DEFAULT,
1012                             &input_token,
1013                             &conf_state,
1014                             &output_token);
1015         if (GSS_ERROR(maj_stat)) {
1016                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap failed: %s\n",
1017                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1018                 return NT_STATUS_ACCESS_DENIED;
1019         }
1020
1021         if (output_token.length < input_token.length) {
1022                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
1023                           (long)output_token.length, (long)length));
1024                 return NT_STATUS_INTERNAL_ERROR;
1025         }
1026         sig_length = output_token.length - input_token.length;
1027
1028         memcpy(data, ((uint8_t *)output_token.value) + sig_length, length);
1029         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
1030
1031         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1032         dump_data_pw("gensec_gssapi_seal_packet: clear\n", data, length);
1033         dump_data_pw("gensec_gssapi_seal_packet: sealed\n", ((uint8_t *)output_token.value) + sig_length, output_token.length - sig_length);
1034
1035         gss_release_buffer(&min_stat, &output_token);
1036
1037         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1038             && !conf_state) {
1039                 return NT_STATUS_ACCESS_DENIED;
1040         }
1041         return NT_STATUS_OK;
1042 }
1043
1044 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
1045                                             uint8_t *data, size_t length,
1046                                             const uint8_t *whole_pdu, size_t pdu_length,
1047                                             const DATA_BLOB *sig)
1048 {
1049         struct gensec_gssapi_state *gensec_gssapi_state
1050                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1051         OM_uint32 maj_stat, min_stat;
1052         gss_buffer_desc input_token, output_token;
1053         int conf_state;
1054         gss_qop_t qop_state;
1055         DATA_BLOB in;
1056
1057         dump_data_pw("gensec_gssapi_unseal_packet: sig\n", sig->data, sig->length);
1058
1059         in = data_blob_talloc(gensec_security, NULL, sig->length + length);
1060
1061         memcpy(in.data, sig->data, sig->length);
1062         memcpy(in.data + sig->length, data, length);
1063
1064         input_token.length = in.length;
1065         input_token.value = in.data;
1066
1067         maj_stat = gss_unwrap(&min_stat,
1068                               gensec_gssapi_state->gssapi_context,
1069                               &input_token,
1070                               &output_token,
1071                               &conf_state,
1072                               &qop_state);
1073         talloc_free(in.data);
1074         if (GSS_ERROR(maj_stat)) {
1075                 char *error_string = gssapi_error_string(NULL, maj_stat, min_stat, gensec_gssapi_state->gss_oid);
1076                 DEBUG(1, ("gensec_gssapi_unseal_packet: GSS UnWrap failed: %s\n",
1077                           error_string));
1078                 talloc_free(error_string);
1079                 return NT_STATUS_ACCESS_DENIED;
1080         }
1081
1082         if (output_token.length != length) {
1083                 return NT_STATUS_INTERNAL_ERROR;
1084         }
1085
1086         memcpy(data, output_token.value, length);
1087
1088         gss_release_buffer(&min_stat, &output_token);
1089
1090         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1091             && !conf_state) {
1092                 return NT_STATUS_ACCESS_DENIED;
1093         }
1094         return NT_STATUS_OK;
1095 }
1096
1097 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1098                                           TALLOC_CTX *mem_ctx,
1099                                           const uint8_t *data, size_t length,
1100                                           const uint8_t *whole_pdu, size_t pdu_length,
1101                                           DATA_BLOB *sig)
1102 {
1103         struct gensec_gssapi_state *gensec_gssapi_state
1104                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1105         OM_uint32 maj_stat, min_stat;
1106         gss_buffer_desc input_token, output_token;
1107
1108         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1109                 input_token.length = pdu_length;
1110                 input_token.value = discard_const_p(uint8_t *, whole_pdu);
1111         } else {
1112                 input_token.length = length;
1113                 input_token.value = discard_const_p(uint8_t *, data);
1114         }
1115
1116         maj_stat = gss_get_mic(&min_stat,
1117                             gensec_gssapi_state->gssapi_context,
1118                             GSS_C_QOP_DEFAULT,
1119                             &input_token,
1120                             &output_token);
1121         if (GSS_ERROR(maj_stat)) {
1122                 DEBUG(1, ("GSS GetMic failed: %s\n",
1123                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1124                 return NT_STATUS_ACCESS_DENIED;
1125         }
1126
1127         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, output_token.length);
1128
1129         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1130
1131         gss_release_buffer(&min_stat, &output_token);
1132
1133         return NT_STATUS_OK;
1134 }
1135
1136 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1137                                            const uint8_t *data, size_t length,
1138                                            const uint8_t *whole_pdu, size_t pdu_length,
1139                                            const DATA_BLOB *sig)
1140 {
1141         struct gensec_gssapi_state *gensec_gssapi_state
1142                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1143         OM_uint32 maj_stat, min_stat;
1144         gss_buffer_desc input_token;
1145         gss_buffer_desc input_message;
1146         gss_qop_t qop_state;
1147
1148         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1149
1150         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1151                 input_message.length = pdu_length;
1152                 input_message.value = discard_const(whole_pdu);
1153         } else {
1154                 input_message.length = length;
1155                 input_message.value = discard_const(data);
1156         }
1157
1158         input_token.length = sig->length;
1159         input_token.value = sig->data;
1160
1161         maj_stat = gss_verify_mic(&min_stat,
1162                               gensec_gssapi_state->gssapi_context,
1163                               &input_message,
1164                               &input_token,
1165                               &qop_state);
1166         if (GSS_ERROR(maj_stat)) {
1167                 char *error_string = gssapi_error_string(NULL, maj_stat, min_stat, gensec_gssapi_state->gss_oid);
1168                 DEBUG(1, ("GSS VerifyMic failed: %s\n", error_string));
1169                 talloc_free(error_string);
1170
1171                 return NT_STATUS_ACCESS_DENIED;
1172         }
1173
1174         return NT_STATUS_OK;
1175 }
1176
1177 /* Try to figure out what features we actually got on the connection */
1178 static bool gensec_gssapi_have_feature(struct gensec_security *gensec_security,
1179                                        uint32_t feature)
1180 {
1181         struct gensec_gssapi_state *gensec_gssapi_state
1182                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1183         if (feature & GENSEC_FEATURE_SIGN) {
1184                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1185                 if (gensec_gssapi_state->sasl
1186                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1187                         return ((gensec_gssapi_state->sasl_protection & NEG_SIGN)
1188                                 && (gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG));
1189                 }
1190                 return gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG;
1191         }
1192         if (feature & GENSEC_FEATURE_SEAL) {
1193                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1194                 if (gensec_gssapi_state->sasl
1195                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1196                         return ((gensec_gssapi_state->sasl_protection & NEG_SEAL)
1197                                  && (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG));
1198                 }
1199                 return gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG;
1200         }
1201         if (feature & GENSEC_FEATURE_SESSION_KEY) {
1202                 /* Only for GSSAPI/Krb5 */
1203                 if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
1204                         return true;
1205                 }
1206         }
1207         if (feature & GENSEC_FEATURE_DCE_STYLE) {
1208                 return gensec_gssapi_state->gss_got_flags & GSS_C_DCE_STYLE;
1209         }
1210         if (feature & GENSEC_FEATURE_NEW_SPNEGO) {
1211                 NTSTATUS status;
1212                 uint32_t keytype;
1213
1214                 if (!(gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG)) {
1215                         return false;
1216                 }
1217
1218                 if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "force_new_spnego", false)) {
1219                         return true;
1220                 }
1221                 if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "disable_new_spnego", false)) {
1222                         return false;
1223                 }
1224
1225                 status = gssapi_get_session_key(gensec_gssapi_state,
1226                                                 gensec_gssapi_state->gssapi_context, NULL, &keytype);
1227                 /*
1228                  * We should do a proper sig on the mechListMic unless
1229                  * we know we have to be backwards compatible with
1230                  * earlier windows versions.
1231                  *
1232                  * Negotiating a non-krb5
1233                  * mech for example should be regarded as having
1234                  * NEW_SPNEGO
1235                  */
1236                 if (NT_STATUS_IS_OK(status)) {
1237                         switch (keytype) {
1238                         case ENCTYPE_DES_CBC_CRC:
1239                         case ENCTYPE_DES_CBC_MD5:
1240                         case ENCTYPE_ARCFOUR_HMAC:
1241                         case ENCTYPE_DES3_CBC_SHA1:
1242                                 return false;
1243                         }
1244                 }
1245                 return true;
1246         }
1247         /* We can always do async (rather than strict request/reply) packets.  */
1248         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1249                 return true;
1250         }
1251         return false;
1252 }
1253
1254 /*
1255  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1256  * (for encrypting some passwords).
1257  *
1258  * This breaks all the abstractions, but what do you expect...
1259  */
1260 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1261                                           TALLOC_CTX *mem_ctx,
1262                                           DATA_BLOB *session_key)
1263 {
1264         struct gensec_gssapi_state *gensec_gssapi_state
1265                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1266         return gssapi_get_session_key(mem_ctx, gensec_gssapi_state->gssapi_context, session_key, NULL);
1267 }
1268
1269 /* Get some basic (and authorization) information about the user on
1270  * this session.  This uses either the PAC (if present) or a local
1271  * database lookup */
1272 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1273                                            TALLOC_CTX *mem_ctx,
1274                                            struct auth_session_info **_session_info)
1275 {
1276         NTSTATUS nt_status;
1277         TALLOC_CTX *tmp_ctx;
1278         struct gensec_gssapi_state *gensec_gssapi_state
1279                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1280         struct auth_session_info *session_info = NULL;
1281         OM_uint32 maj_stat, min_stat;
1282         DATA_BLOB pac_blob, *pac_blob_ptr = NULL;
1283
1284         gss_buffer_desc name_token;
1285         char *principal_string;
1286
1287         tmp_ctx = talloc_named(mem_ctx, 0, "gensec_gssapi_session_info context");
1288         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
1289
1290         maj_stat = gss_display_name (&min_stat,
1291                                      gensec_gssapi_state->client_name,
1292                                      &name_token,
1293                                      NULL);
1294         if (GSS_ERROR(maj_stat)) {
1295                 DEBUG(1, ("GSS display_name failed: %s\n",
1296                           gssapi_error_string(tmp_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1297                 talloc_free(tmp_ctx);
1298                 return NT_STATUS_FOOBAR;
1299         }
1300
1301         principal_string = talloc_strndup(tmp_ctx,
1302                                           (const char *)name_token.value,
1303                                           name_token.length);
1304
1305         gss_release_buffer(&min_stat, &name_token);
1306
1307         if (!principal_string) {
1308                 talloc_free(tmp_ctx);
1309                 return NT_STATUS_NO_MEMORY;
1310         }
1311
1312         nt_status = gssapi_obtain_pac_blob(tmp_ctx,  gensec_gssapi_state->gssapi_context,
1313                                            gensec_gssapi_state->client_name,
1314                                            &pac_blob);
1315
1316         /* IF we have the PAC - otherwise we need to get this
1317          * data from elsewere - local ldb, or (TODO) lookup of some
1318          * kind...
1319          */
1320         if (NT_STATUS_IS_OK(nt_status)) {
1321                 pac_blob_ptr = &pac_blob;
1322         }
1323         nt_status = gensec_generate_session_info_pac(tmp_ctx,
1324                                                      gensec_security,
1325                                                      gensec_gssapi_state->smb_krb5_context,
1326                                                      pac_blob_ptr, principal_string,
1327                                                      gensec_get_remote_address(gensec_security),
1328                                                      &session_info);
1329         if (!NT_STATUS_IS_OK(nt_status)) {
1330                 talloc_free(tmp_ctx);
1331                 return nt_status;
1332         }
1333
1334         nt_status = gensec_gssapi_session_key(gensec_security, session_info, &session_info->session_key);
1335         if (!NT_STATUS_IS_OK(nt_status)) {
1336                 talloc_free(tmp_ctx);
1337                 return nt_status;
1338         }
1339
1340         if (!(gensec_gssapi_state->gss_got_flags & GSS_C_DELEG_FLAG)) {
1341                 DEBUG(10, ("gensec_gssapi: NO delegated credentials supplied by client\n"));
1342         } else {
1343                 krb5_error_code ret;
1344                 const char *error_string;
1345
1346                 DEBUG(10, ("gensec_gssapi: delegated credentials supplied by client\n"));
1347                 session_info->credentials = cli_credentials_init(session_info);
1348                 if (!session_info->credentials) {
1349                         talloc_free(tmp_ctx);
1350                         return NT_STATUS_NO_MEMORY;
1351                 }
1352
1353                 cli_credentials_set_conf(session_info->credentials, gensec_security->settings->lp_ctx);
1354                 /* Just so we don't segfault trying to get at a username */
1355                 cli_credentials_set_anonymous(session_info->credentials);
1356
1357                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1358                                                            gensec_security->settings->lp_ctx,
1359                                                            gensec_gssapi_state->delegated_cred_handle,
1360                                                            CRED_SPECIFIED, &error_string);
1361                 if (ret) {
1362                         talloc_free(tmp_ctx);
1363                         DEBUG(2,("Failed to get gss creds: %s\n", error_string));
1364                         return NT_STATUS_NO_MEMORY;
1365                 }
1366
1367                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1368                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1369
1370                 /* It has been taken from this place... */
1371                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1372         }
1373         *_session_info = talloc_steal(mem_ctx, session_info);
1374         talloc_free(tmp_ctx);
1375
1376         return NT_STATUS_OK;
1377 }
1378
1379 static size_t gensec_gssapi_sig_size(struct gensec_security *gensec_security, size_t data_size)
1380 {
1381         struct gensec_gssapi_state *gensec_gssapi_state
1382                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1383         NTSTATUS status;
1384
1385         if (gensec_gssapi_state->sig_size) {
1386                 return gensec_gssapi_state->sig_size;
1387         }
1388
1389         if (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG) {
1390                 gensec_gssapi_state->sig_size = 45;
1391         } else {
1392                 gensec_gssapi_state->sig_size = 37;
1393         }
1394
1395         status = gensec_gssapi_init_lucid(gensec_gssapi_state);
1396         if (!NT_STATUS_IS_OK(status)) {
1397                 return gensec_gssapi_state->sig_size;
1398         }
1399
1400         if (gensec_gssapi_state->lucid->protocol == 1) {
1401                 if (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG) {
1402                         /*
1403                          * TODO: windows uses 76 here, but we don't know
1404                          *       gss_wrap works with aes keys yet
1405                          */
1406                         gensec_gssapi_state->sig_size = 76;
1407                 } else {
1408                         gensec_gssapi_state->sig_size = 28;
1409                 }
1410         } else if (gensec_gssapi_state->lucid->protocol == 0) {
1411                 switch (gensec_gssapi_state->lucid->rfc1964_kd.ctx_key.type) {
1412                 case KEYTYPE_DES:
1413                 case KEYTYPE_ARCFOUR:
1414                 case KEYTYPE_ARCFOUR_56:
1415                         if (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG) {
1416                                 gensec_gssapi_state->sig_size = 45;
1417                         } else {
1418                                 gensec_gssapi_state->sig_size = 37;
1419                         }
1420                         break;
1421                 case KEYTYPE_DES3:
1422                         if (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG) {
1423                                 gensec_gssapi_state->sig_size = 57;
1424                         } else {
1425                                 gensec_gssapi_state->sig_size = 49;
1426                         }
1427                         break;
1428                 }
1429         }
1430
1431         return gensec_gssapi_state->sig_size;
1432 }
1433
1434 static const char *gensec_gssapi_krb5_oids[] = {
1435         GENSEC_OID_KERBEROS5_OLD,
1436         GENSEC_OID_KERBEROS5,
1437         NULL
1438 };
1439
1440 static const char *gensec_gssapi_spnego_oids[] = {
1441         GENSEC_OID_SPNEGO,
1442         NULL
1443 };
1444
1445 /* As a server, this could in theory accept any GSSAPI mech */
1446 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1447         .name           = "gssapi_spnego",
1448         .sasl_name      = "GSS-SPNEGO",
1449         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1450         .oid            = gensec_gssapi_spnego_oids,
1451         .client_start   = gensec_gssapi_client_start,
1452         .server_start   = gensec_gssapi_server_start,
1453         .magic          = gensec_magic_check_krb5_oid,
1454         .update         = gensec_gssapi_update,
1455         .session_key    = gensec_gssapi_session_key,
1456         .session_info   = gensec_gssapi_session_info,
1457         .sign_packet    = gensec_gssapi_sign_packet,
1458         .check_packet   = gensec_gssapi_check_packet,
1459         .seal_packet    = gensec_gssapi_seal_packet,
1460         .unseal_packet  = gensec_gssapi_unseal_packet,
1461         .wrap           = gensec_gssapi_wrap,
1462         .unwrap         = gensec_gssapi_unwrap,
1463         .have_feature   = gensec_gssapi_have_feature,
1464         .enabled        = false,
1465         .kerberos       = true,
1466         .priority       = GENSEC_GSSAPI
1467 };
1468
1469 /* As a server, this could in theory accept any GSSAPI mech */
1470 static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
1471         .name           = "gssapi_krb5",
1472         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1473         .oid            = gensec_gssapi_krb5_oids,
1474         .client_start   = gensec_gssapi_client_start,
1475         .server_start   = gensec_gssapi_server_start,
1476         .magic          = gensec_magic_check_krb5_oid,
1477         .update         = gensec_gssapi_update,
1478         .session_key    = gensec_gssapi_session_key,
1479         .session_info   = gensec_gssapi_session_info,
1480         .sig_size       = gensec_gssapi_sig_size,
1481         .sign_packet    = gensec_gssapi_sign_packet,
1482         .check_packet   = gensec_gssapi_check_packet,
1483         .seal_packet    = gensec_gssapi_seal_packet,
1484         .unseal_packet  = gensec_gssapi_unseal_packet,
1485         .wrap           = gensec_gssapi_wrap,
1486         .unwrap         = gensec_gssapi_unwrap,
1487         .have_feature   = gensec_gssapi_have_feature,
1488         .enabled        = true,
1489         .kerberos       = true,
1490         .priority       = GENSEC_GSSAPI
1491 };
1492
1493 /* As a server, this could in theory accept any GSSAPI mech */
1494 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1495         .name             = "gssapi_krb5_sasl",
1496         .sasl_name        = "GSSAPI",
1497         .client_start     = gensec_gssapi_sasl_client_start,
1498         .server_start     = gensec_gssapi_sasl_server_start,
1499         .update           = gensec_gssapi_update,
1500         .session_key      = gensec_gssapi_session_key,
1501         .session_info     = gensec_gssapi_session_info,
1502         .max_input_size   = gensec_gssapi_max_input_size,
1503         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1504         .wrap             = gensec_gssapi_wrap,
1505         .unwrap           = gensec_gssapi_unwrap,
1506         .have_feature     = gensec_gssapi_have_feature,
1507         .enabled          = true,
1508         .kerberos         = true,
1509         .priority         = GENSEC_GSSAPI
1510 };
1511
1512 _PUBLIC_ NTSTATUS gensec_gssapi_init(void)
1513 {
1514         NTSTATUS ret;
1515
1516         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1517         if (!NT_STATUS_IS_OK(ret)) {
1518                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1519                         gensec_gssapi_spnego_security_ops.name));
1520                 return ret;
1521         }
1522
1523         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1524         if (!NT_STATUS_IS_OK(ret)) {
1525                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1526                         gensec_gssapi_krb5_security_ops.name));
1527                 return ret;
1528         }
1529
1530         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1531         if (!NT_STATUS_IS_OK(ret)) {
1532                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1533                         gensec_gssapi_sasl_krb5_security_ops.name));
1534                 return ret;
1535         }
1536
1537         return ret;
1538 }