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/gen_ndr/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_internal.h"
  38 #include "auth/gensec/gensec_proto.h"
  39 #include "auth/gensec/gensec_toplevel_proto.h"
  40 #include "param/param.h"
  41 #include "auth/session_proto.h"
  42 #include "gensec_gssapi.h"
  43 #include "lib/util/util_net.h"
  44 #include "auth/kerberos/pac_utils.h"
  45 #include "auth/kerberos/gssapi_helper.h"
  46
  47 #ifndef gss_mech_spnego
  48 gss_OID_desc spnego_mech_oid_desc =
  49                 { 6, discard_const_p(void, "\x2b\x06\x01\x05\x05\x02") };
  50 #define gss_mech_spnego (&spnego_mech_oid_desc)
  51 #endif
  52
  53 _PUBLIC_ NTSTATUS gensec_gssapi_init(void);
  54
  55 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security);
  56 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security);
  57 static size_t gensec_gssapi_sig_size(struct gensec_security *gensec_security, size_t data_size);
  58
  59 static int gensec_gssapi_destructor(struct gensec_gssapi_state *gensec_gssapi_state)
  60 {
  61         OM_uint32 min_stat;
  62
  63         if (gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
  64                 gss_release_cred(&min_stat,
  65                                  &gensec_gssapi_state->delegated_cred_handle);
  66         }
  67
  68         if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
  69                 gss_delete_sec_context(&min_stat,
  70                                        &gensec_gssapi_state->gssapi_context,
  71                                        GSS_C_NO_BUFFER);
  72         }
  73
  74         if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
  75                 gss_release_name(&min_stat,
  76                                  &gensec_gssapi_state->server_name);
  77         }
  78         if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
  79                 gss_release_name(&min_stat,
  80                                  &gensec_gssapi_state->client_name);
  81         }
  82
  83         return 0;
  84 }
  85
  86 static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
  87 {
  88         struct gensec_gssapi_state *gensec_gssapi_state;
  89         krb5_error_code ret;
  90         const char *realm;
  91
  92         gensec_gssapi_state = talloc_zero(gensec_security, struct gensec_gssapi_state);
  93         if (!gensec_gssapi_state) {
  94                 return NT_STATUS_NO_MEMORY;
  95         }
  96
  97         gensec_security->private_data = gensec_gssapi_state;
  98
  99         gensec_gssapi_state->gssapi_context = GSS_C_NO_CONTEXT;
 100
 101         /* TODO: Fill in channel bindings */
 102         gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
 103
 104         gensec_gssapi_state->server_name = GSS_C_NO_NAME;
 105         gensec_gssapi_state->client_name = GSS_C_NO_NAME;
 106
 107         gensec_gssapi_state->gss_want_flags = 0;
 108         gensec_gssapi_state->expire_time = GENSEC_EXPIRE_TIME_INFINITY;
 109
 110         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation_by_kdc_policy", true)) {
 111                 gensec_gssapi_state->gss_want_flags |= GSS_C_DELEG_POLICY_FLAG;
 112         }
 113         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "mutual", true)) {
 114                 gensec_gssapi_state->gss_want_flags |= GSS_C_MUTUAL_FLAG;
 115         }
 116         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation", true)) {
 117                 gensec_gssapi_state->gss_want_flags |= GSS_C_DELEG_FLAG;
 118         }
 119         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "replay", true)) {
 120                 gensec_gssapi_state->gss_want_flags |= GSS_C_REPLAY_FLAG;
 121         }
 122         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "sequence", true)) {
 123                 gensec_gssapi_state->gss_want_flags |= GSS_C_SEQUENCE_FLAG;
 124         }
 125
 126         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 127                 gensec_gssapi_state->gss_want_flags |= GSS_C_INTEG_FLAG;
 128         }
 129         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 130                 gensec_gssapi_state->gss_want_flags |= GSS_C_INTEG_FLAG;
 131                 gensec_gssapi_state->gss_want_flags |= GSS_C_CONF_FLAG;
 132         }
 133         if (gensec_security->want_features & GENSEC_FEATURE_DCE_STYLE) {
 134                 gensec_gssapi_state->gss_want_flags |= GSS_C_DCE_STYLE;
 135         }
 136
 137         gensec_gssapi_state->gss_got_flags = 0;
 138
 139         switch (gensec_security->ops->auth_type) {
 140         case DCERPC_AUTH_TYPE_SPNEGO:
 141                 gensec_gssapi_state->gss_oid = gss_mech_spnego;
 142                 break;
 143         case DCERPC_AUTH_TYPE_KRB5:
 144         default:
 145                 gensec_gssapi_state->gss_oid =
 146                         discard_const_p(void, gss_mech_krb5);
 147                 break;
 148         }
 149
 150         ret = smb_krb5_init_context(gensec_gssapi_state,
 151                                     gensec_security->settings->lp_ctx,
 152                                     &gensec_gssapi_state->smb_krb5_context);
 153         if (ret) {
 154                 DEBUG(1,("gensec_gssapi_start: smb_krb5_init_context failed (%s)\n",
 155                          error_message(ret)));
 156                 talloc_free(gensec_gssapi_state);
 157                 return NT_STATUS_INTERNAL_ERROR;
 158         }
 159
 160         gensec_gssapi_state->client_cred = NULL;
 161         gensec_gssapi_state->server_cred = NULL;
 162
 163         gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 164
 165         gensec_gssapi_state->sasl = false;
 166         gensec_gssapi_state->sasl_state = STAGE_GSS_NEG;
 167         gensec_gssapi_state->sasl_protection = 0;
 168
 169         gensec_gssapi_state->max_wrap_buf_size
 170                 = gensec_setting_int(gensec_security->settings, "gensec_gssapi", "max wrap buf size", 65536);
 171         gensec_gssapi_state->gss_exchange_count = 0;
 172         gensec_gssapi_state->sig_size = 0;
 173
 174         talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 175
 176 #ifdef SAMBA4_USES_HEIMDAL
 177         realm = lpcfg_realm(gensec_security->settings->lp_ctx);
 178         if (realm != NULL) {
 179                 ret = gsskrb5_set_default_realm(realm);
 180                 if (ret) {
 181                         DEBUG(1,("gensec_gssapi_start: gsskrb5_set_default_realm failed\n"));
 182                         talloc_free(gensec_gssapi_state);
 183                         return NT_STATUS_INTERNAL_ERROR;
 184                 }
 185         }
 186
 187         /* don't do DNS lookups of any kind, it might/will fail for a netbios name */
 188         ret = gsskrb5_set_dns_canonicalize(gensec_setting_bool(gensec_security->settings, "krb5", "set_dns_canonicalize", false));
 189         if (ret) {
 190                 DEBUG(1,("gensec_gssapi_start: gsskrb5_set_dns_canonicalize failed\n"));
 191                 talloc_free(gensec_gssapi_state);
 192                 return NT_STATUS_INTERNAL_ERROR;
 193         }
 194 #endif
 195         return NT_STATUS_OK;
 196 }
 197
 198 static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
 199 {
 200         NTSTATUS nt_status;
 201         int ret;
 202         struct gensec_gssapi_state *gensec_gssapi_state;
 203         struct cli_credentials *machine_account;
 204         struct gssapi_creds_container *gcc;
 205
 206         nt_status = gensec_gssapi_start(gensec_security);
 207         if (!NT_STATUS_IS_OK(nt_status)) {
 208                 return nt_status;
 209         }
 210
 211         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 212
 213         machine_account = gensec_get_credentials(gensec_security);
 214
 215         if (!machine_account) {
 216                 DEBUG(3, ("No machine account credentials specified\n"));
 217                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 218         } else {
 219                 ret = cli_credentials_get_server_gss_creds(machine_account,
 220                                                            gensec_security->settings->lp_ctx, &gcc);
 221                 if (ret) {
 222                         DEBUG(1, ("Aquiring acceptor credentials failed: %s\n",
 223                                   error_message(ret)));
 224                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 225                 }
 226         }
 227
 228         gensec_gssapi_state->server_cred = gcc;
 229         return NT_STATUS_OK;
 230
 231 }
 232
 233 static NTSTATUS gensec_gssapi_sasl_server_start(struct gensec_security *gensec_security)
 234 {
 235         NTSTATUS nt_status;
 236         struct gensec_gssapi_state *gensec_gssapi_state;
 237         nt_status = gensec_gssapi_server_start(gensec_security);
 238
 239         if (NT_STATUS_IS_OK(nt_status)) {
 240                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 241                 gensec_gssapi_state->sasl = true;
 242         }
 243         return nt_status;
 244 }
 245
 246 static NTSTATUS gensec_gssapi_client_creds(struct gensec_security *gensec_security,
 247                                            struct tevent_context *ev)
 248 {
 249         struct gensec_gssapi_state *gensec_gssapi_state;
 250         struct gssapi_creds_container *gcc;
 251         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 252         const char *error_string;
 253         int ret;
 254
 255         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 256
 257         /* Only run this the first time the update() call is made */
 258         if (gensec_gssapi_state->client_cred) {
 259                 return NT_STATUS_OK;
 260         }
 261
 262         ret = cli_credentials_get_client_gss_creds(creds,
 263                                                    ev,
 264                                                    gensec_security->settings->lp_ctx, &gcc, &error_string);
 265         switch (ret) {
 266         case 0:
 267                 break;
 268         case EINVAL:
 269                 DEBUG(3, ("Cannot obtain client GSS credentials we need to contact %s : %s\n", gensec_gssapi_state->target_principal, error_string));
 270                 return NT_STATUS_INVALID_PARAMETER;
 271         case KRB5KDC_ERR_PREAUTH_FAILED:
 272         case KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN:
 273         case KRB5KRB_AP_ERR_BAD_INTEGRITY:
 274                 DEBUG(1, ("Wrong username or password: %s\n", error_string));
 275                 return NT_STATUS_LOGON_FAILURE;
 276         case KRB5KDC_ERR_CLIENT_REVOKED:
 277                 DEBUG(1, ("Account locked out: %s\n", error_string));
 278                 return NT_STATUS_ACCOUNT_LOCKED_OUT;
 279         case KRB5_KDC_UNREACH:
 280                 DEBUG(3, ("Cannot reach a KDC we require to contact %s : %s\n", gensec_gssapi_state->target_principal, error_string));
 281                 return NT_STATUS_NO_LOGON_SERVERS;
 282         case KRB5_CC_NOTFOUND:
 283         case KRB5_CC_END:
 284                 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));
 285                 return NT_STATUS_TIME_DIFFERENCE_AT_DC;
 286         default:
 287                 DEBUG(1, ("Aquiring initiator credentials failed: %s\n", error_string));
 288                 return NT_STATUS_UNSUCCESSFUL;
 289         }
 290
 291         gensec_gssapi_state->client_cred = gcc;
 292         if (!talloc_reference(gensec_gssapi_state, gcc)) {
 293                 return NT_STATUS_NO_MEMORY;
 294         }
 295
 296         return NT_STATUS_OK;
 297 }
 298
 299 static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
 300 {
 301         struct gensec_gssapi_state *gensec_gssapi_state;
 302         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 303         NTSTATUS nt_status;
 304         gss_buffer_desc name_token;
 305         gss_OID name_type;
 306         OM_uint32 maj_stat, min_stat;
 307         const char *hostname = gensec_get_target_hostname(gensec_security);
 308
 309         if (!hostname) {
 310                 DEBUG(3, ("No hostname for target computer passed in, cannot use kerberos for this connection\n"));
 311                 return NT_STATUS_INVALID_PARAMETER;
 312         }
 313         if (is_ipaddress(hostname)) {
 314                 DEBUG(2, ("Cannot do GSSAPI to an IP address\n"));
 315                 return NT_STATUS_INVALID_PARAMETER;
 316         }
 317         if (strcmp(hostname, "localhost") == 0) {
 318                 DEBUG(2, ("GSSAPI to 'localhost' does not make sense\n"));
 319                 return NT_STATUS_INVALID_PARAMETER;
 320         }
 321
 322         nt_status = gensec_gssapi_start(gensec_security);
 323         if (!NT_STATUS_IS_OK(nt_status)) {
 324                 return nt_status;
 325         }
 326
 327         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 328
 329         if (cli_credentials_get_impersonate_principal(creds)) {
 330                 gensec_gssapi_state->gss_want_flags &= ~(GSS_C_DELEG_FLAG|GSS_C_DELEG_POLICY_FLAG);
 331         }
 332
 333         gensec_gssapi_state->target_principal = gensec_get_target_principal(gensec_security);
 334         if (gensec_gssapi_state->target_principal) {
 335                 name_type = GSS_C_NULL_OID;
 336         } else {
 337                 gensec_gssapi_state->target_principal = talloc_asprintf(gensec_gssapi_state, "%s/%s@%s",
 338                                             gensec_get_target_service(gensec_security),
 339                                             hostname, lpcfg_realm(gensec_security->settings->lp_ctx));
 340
 341                 name_type = GSS_C_NT_USER_NAME;
 342         }
 343         name_token.value  = discard_const_p(uint8_t, gensec_gssapi_state->target_principal);
 344         name_token.length = strlen(gensec_gssapi_state->target_principal);
 345
 346
 347         maj_stat = gss_import_name (&min_stat,
 348                                     &name_token,
 349                                     name_type,
 350                                     &gensec_gssapi_state->server_name);
 351         if (maj_stat) {
 352                 DEBUG(2, ("GSS Import name of %s failed: %s\n",
 353                           (char *)name_token.value,
 354                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 355                 return NT_STATUS_INVALID_PARAMETER;
 356         }
 357
 358         return NT_STATUS_OK;
 359 }
 360
 361 static NTSTATUS gensec_gssapi_sasl_client_start(struct gensec_security *gensec_security)
 362 {
 363         NTSTATUS nt_status;
 364         struct gensec_gssapi_state *gensec_gssapi_state;
 365         nt_status = gensec_gssapi_client_start(gensec_security);
 366
 367         if (NT_STATUS_IS_OK(nt_status)) {
 368                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 369                 gensec_gssapi_state->sasl = true;
 370         }
 371         return nt_status;
 372 }
 373
 374
 375 /**
 376  * Next state function for the GSSAPI GENSEC mechanism
 377  *
 378  * @param gensec_gssapi_state GSSAPI State
 379  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 380  * @param in The request, as a DATA_BLOB
 381  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 382  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 383  *                or NT_STATUS_OK if the user is authenticated.
 384  */
 385
 386 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 387                                      TALLOC_CTX *out_mem_ctx,
 388                                      struct tevent_context *ev,
 389                                      const DATA_BLOB in, DATA_BLOB *out)
 390 {
 391         struct gensec_gssapi_state *gensec_gssapi_state
 392                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 393         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 394         OM_uint32 maj_stat, min_stat;
 395         OM_uint32 min_stat2;
 396         gss_buffer_desc input_token = { 0, NULL };
 397         gss_buffer_desc output_token = { 0, NULL };
 398
 399         gss_OID gss_oid_p = NULL;
 400         OM_uint32 time_req = 0;
 401         OM_uint32 time_rec = 0;
 402         struct timeval tv;
 403
 404         time_req = gensec_setting_int(gensec_security->settings,
 405                                       "gensec_gssapi", "requested_life_time",
 406                                       time_req);
 407
 408         input_token.length = in.length;
 409         input_token.value = in.data;
 410
 411         switch (gensec_gssapi_state->sasl_state) {
 412         case STAGE_GSS_NEG:
 413         {
 414                 switch (gensec_security->gensec_role) {
 415                 case GENSEC_CLIENT:
 416                 {
 417 #ifdef SAMBA4_USES_HEIMDAL
 418                         struct gsskrb5_send_to_kdc send_to_kdc;
 419 #endif
 420                         krb5_error_code ret;
 421
 422                         nt_status = gensec_gssapi_client_creds(gensec_security, ev);
 423                         if (!NT_STATUS_IS_OK(nt_status)) {
 424                                 return nt_status;
 425                         }
 426
 427 #ifdef SAMBA4_USES_HEIMDAL
 428                         send_to_kdc.func = smb_krb5_send_and_recv_func;
 429                         send_to_kdc.ptr = ev;
 430
 431                         min_stat = gsskrb5_set_send_to_kdc(&send_to_kdc);
 432                         if (min_stat) {
 433                                 DEBUG(1,("gensec_gssapi_update: gsskrb5_set_send_to_kdc failed\n"));
 434                                 return NT_STATUS_INTERNAL_ERROR;
 435                         }
 436 #endif
 437                         maj_stat = gss_init_sec_context(&min_stat,
 438                                                         gensec_gssapi_state->client_cred->creds,
 439                                                         &gensec_gssapi_state->gssapi_context,
 440                                                         gensec_gssapi_state->server_name,
 441                                                         gensec_gssapi_state->gss_oid,
 442                                                         gensec_gssapi_state->gss_want_flags,
 443                                                         time_req,
 444                                                         gensec_gssapi_state->input_chan_bindings,
 445                                                         &input_token,
 446                                                         &gss_oid_p,
 447                                                         &output_token,
 448                                                         &gensec_gssapi_state->gss_got_flags, /* ret flags */
 449                                                         &time_rec);
 450                         if (gss_oid_p) {
 451                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 452                         }
 453
 454 #ifdef SAMBA4_USES_HEIMDAL
 455                         send_to_kdc.func = smb_krb5_send_and_recv_func;
 456                         send_to_kdc.ptr = NULL;
 457
 458                         ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
 459                         if (ret) {
 460                                 DEBUG(1,("gensec_gssapi_update: gsskrb5_set_send_to_kdc failed\n"));
 461                                 return NT_STATUS_INTERNAL_ERROR;
 462                         }
 463 #endif
 464                         break;
 465                 }
 466                 case GENSEC_SERVER:
 467                 {
 468                         maj_stat = gss_accept_sec_context(&min_stat,
 469                                                           &gensec_gssapi_state->gssapi_context,
 470                                                           gensec_gssapi_state->server_cred->creds,
 471                                                           &input_token,
 472                                                           gensec_gssapi_state->input_chan_bindings,
 473                                                           &gensec_gssapi_state->client_name,
 474                                                           &gss_oid_p,
 475                                                           &output_token,
 476                                                           &gensec_gssapi_state->gss_got_flags,
 477                                                           &time_rec,
 478                                                           &gensec_gssapi_state->delegated_cred_handle);
 479                         if (gss_oid_p) {
 480                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 481                         }
 482                         break;
 483                 }
 484                 default:
 485                         return NT_STATUS_INVALID_PARAMETER;
 486
 487                 }
 488
 489                 gensec_gssapi_state->gss_exchange_count++;
 490
 491                 if (maj_stat == GSS_S_COMPLETE) {
 492                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 493                         gss_release_buffer(&min_stat2, &output_token);
 494
 495                         if (gensec_gssapi_state->gss_got_flags & GSS_C_DELEG_FLAG &&
 496                             gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
 497                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 498                         } else {
 499                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 500                         }
 501
 502                         tv = timeval_current_ofs(time_rec, 0);
 503                         gensec_gssapi_state->expire_time = timeval_to_nttime(&tv);
 504
 505                         /* We may have been invoked as SASL, so there
 506                          * is more work to do */
 507                         if (gensec_gssapi_state->sasl) {
 508                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 509                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 510                         } else {
 511                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 512
 513                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 514                                         DEBUG(5, ("GSSAPI Connection will be cryptographically sealed\n"));
 515                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 516                                         DEBUG(5, ("GSSAPI Connection will be cryptographically signed\n"));
 517                                 } else {
 518                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 519                                 }
 520
 521                                 return NT_STATUS_OK;
 522                         }
 523                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 524                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 525                         gss_release_buffer(&min_stat2, &output_token);
 526
 527                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 528                 } else if (maj_stat == GSS_S_CONTEXT_EXPIRED) {
 529                         gss_cred_id_t creds = NULL;
 530                         gss_name_t name;
 531                         gss_buffer_desc buffer;
 532                         OM_uint32 lifetime = 0;
 533                         gss_cred_usage_t usage;
 534                         const char *role = NULL;
 535                         DEBUG(0, ("GSS %s Update(krb5)(%d) Update failed, credentials expired during GSSAPI handshake!\n",
 536                                   role,
 537                                   gensec_gssapi_state->gss_exchange_count));
 538
 539
 540                         switch (gensec_security->gensec_role) {
 541                         case GENSEC_CLIENT:
 542                                 creds = gensec_gssapi_state->client_cred->creds;
 543                                 role = "client";
 544                                 break;
 545                         case GENSEC_SERVER:
 546                                 creds = gensec_gssapi_state->server_cred->creds;
 547                                 role = "server";
 548                                 break;
 549                         }
 550
 551                         maj_stat = gss_inquire_cred(&min_stat,
 552                                                     creds,
 553                                                     &name, &lifetime, &usage, NULL);
 554
 555                         if (maj_stat == GSS_S_COMPLETE) {
 556                                 const char *usage_string = NULL;
 557                                 switch (usage) {
 558                                 case GSS_C_BOTH:
 559                                         usage_string = "GSS_C_BOTH";
 560                                         break;
 561                                 case GSS_C_ACCEPT:
 562                                         usage_string = "GSS_C_ACCEPT";
 563                                         break;
 564                                 case GSS_C_INITIATE:
 565                                         usage_string = "GSS_C_INITIATE";
 566                                         break;
 567                                 }
 568                                 maj_stat = gss_display_name(&min_stat, name, &buffer, NULL);
 569                                 if (maj_stat) {
 570                                         buffer.value = NULL;
 571                                         buffer.length = 0;
 572                                 }
 573                                 if (lifetime > 0) {
 574                                         DEBUG(0, ("GSSAPI gss_inquire_cred indicates expiry of %*.*s in %u sec for %s\n",
 575                                                   (int)buffer.length, (int)buffer.length, (char *)buffer.value,
 576                                                   lifetime, usage_string));
 577                                 } else {
 578                                         DEBUG(0, ("GSSAPI gss_inquire_cred indicates %*.*s has already expired for %s\n",
 579                                                   (int)buffer.length, (int)buffer.length, (char *)buffer.value,
 580                                                   usage_string));
 581                                 }
 582                                 gss_release_buffer(&min_stat, &buffer);
 583                                 gss_release_name(&min_stat, &name);
 584                         } else if (maj_stat != GSS_S_COMPLETE) {
 585                                 DEBUG(0, ("inquiry of credential lifefime via GSSAPI gss_inquire_cred failed: %s\n",
 586                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 587                         }
 588                         return NT_STATUS_INVALID_PARAMETER;
 589                 } else if (smb_gss_oid_equal(gensec_gssapi_state->gss_oid,
 590                                              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 ticket 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_LOGON_FAILURE;
 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_LOGON_FAILURE;
 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: determining 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         bool hdr_signing = false;
1001         size_t sig_size = 0;
1002         NTSTATUS status;
1003
1004         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1005                 hdr_signing = true;
1006         }
1007
1008         sig_size = gensec_gssapi_sig_size(gensec_security, length);
1009
1010         status = gssapi_seal_packet(gensec_gssapi_state->gssapi_context,
1011                                     gensec_gssapi_state->gss_oid,
1012                                     hdr_signing, sig_size,
1013                                     data, length,
1014                                     whole_pdu, pdu_length,
1015                                     mem_ctx, sig);
1016         if (!NT_STATUS_IS_OK(status)) {
1017                 DEBUG(0, ("gssapi_seal_packet(hdr_signing=%u,sig_size=%ju,"
1018                           "data=%ju,pdu=%ju) failed: %s\n",
1019                           hdr_signing, sig_size, length, pdu_length,
1020                           nt_errstr(status)));
1021                 return status;
1022         }
1023
1024         return NT_STATUS_OK;
1025 }
1026
1027 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
1028                                             uint8_t *data, size_t length,
1029                                             const uint8_t *whole_pdu, size_t pdu_length,
1030                                             const DATA_BLOB *sig)
1031 {
1032         struct gensec_gssapi_state *gensec_gssapi_state
1033                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1034         bool hdr_signing = false;
1035         NTSTATUS status;
1036
1037         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1038                 hdr_signing = true;
1039         }
1040
1041         status = gssapi_unseal_packet(gensec_gssapi_state->gssapi_context,
1042                                       gensec_gssapi_state->gss_oid,
1043                                       hdr_signing,
1044                                       data, length,
1045                                       whole_pdu, pdu_length,
1046                                       sig);
1047         if (!NT_STATUS_IS_OK(status)) {
1048                 DEBUG(0, ("gssapi_unseal_packet(hdr_signing=%u,sig_size=%ju,"
1049                           "data=%ju,pdu=%ju) failed: %s\n",
1050                           hdr_signing, sig->length, length, pdu_length,
1051                           nt_errstr(status)));
1052                 return status;
1053         }
1054
1055         return NT_STATUS_OK;
1056 }
1057
1058 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1059                                           TALLOC_CTX *mem_ctx,
1060                                           const uint8_t *data, size_t length,
1061                                           const uint8_t *whole_pdu, size_t pdu_length,
1062                                           DATA_BLOB *sig)
1063 {
1064         struct gensec_gssapi_state *gensec_gssapi_state
1065                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1066         bool hdr_signing = false;
1067         NTSTATUS status;
1068
1069         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1070                 hdr_signing = true;
1071         }
1072
1073         status = gssapi_sign_packet(gensec_gssapi_state->gssapi_context,
1074                                     gensec_gssapi_state->gss_oid,
1075                                     hdr_signing,
1076                                     data, length,
1077                                     whole_pdu, pdu_length,
1078                                     mem_ctx, sig);
1079         if (!NT_STATUS_IS_OK(status)) {
1080                 DEBUG(0, ("gssapi_sign_packet(hdr_signing=%u,"
1081                           "data=%ju,pdu=%ju) failed: %s\n",
1082                           hdr_signing, length, pdu_length,
1083                           nt_errstr(status)));
1084                 return status;
1085         }
1086
1087         return NT_STATUS_OK;
1088 }
1089
1090 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1091                                            const uint8_t *data, size_t length,
1092                                            const uint8_t *whole_pdu, size_t pdu_length,
1093                                            const DATA_BLOB *sig)
1094 {
1095         struct gensec_gssapi_state *gensec_gssapi_state
1096                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1097         bool hdr_signing = false;
1098         NTSTATUS status;
1099
1100         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1101                 hdr_signing = true;
1102         }
1103
1104         status = gssapi_check_packet(gensec_gssapi_state->gssapi_context,
1105                                      gensec_gssapi_state->gss_oid,
1106                                      hdr_signing,
1107                                      data, length,
1108                                      whole_pdu, pdu_length,
1109                                      sig);
1110         if (!NT_STATUS_IS_OK(status)) {
1111                 DEBUG(0, ("gssapi_check_packet(hdr_signing=%u,sig_size=%ju,"
1112                           "data=%ju,pdu=%ju) failed: %s\n",
1113                           hdr_signing, sig->length, length, pdu_length,
1114                           nt_errstr(status)));
1115                 return status;
1116         }
1117
1118         return NT_STATUS_OK;
1119 }
1120
1121 /* Try to figure out what features we actually got on the connection */
1122 static bool gensec_gssapi_have_feature(struct gensec_security *gensec_security,
1123                                        uint32_t feature)
1124 {
1125         struct gensec_gssapi_state *gensec_gssapi_state
1126                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1127         if (feature & GENSEC_FEATURE_SIGN) {
1128                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1129                 if (gensec_gssapi_state->sasl
1130                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1131                         return ((gensec_gssapi_state->sasl_protection & NEG_SIGN)
1132                                 && (gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG));
1133                 }
1134                 return gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG;
1135         }
1136         if (feature & GENSEC_FEATURE_SEAL) {
1137                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1138                 if (gensec_gssapi_state->sasl
1139                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1140                         return ((gensec_gssapi_state->sasl_protection & NEG_SEAL)
1141                                  && (gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG));
1142                 }
1143                 return gensec_gssapi_state->gss_got_flags & GSS_C_CONF_FLAG;
1144         }
1145         if (feature & GENSEC_FEATURE_SESSION_KEY) {
1146                 /* Only for GSSAPI/Krb5 */
1147                 if (smb_gss_oid_equal(gensec_gssapi_state->gss_oid,
1148                                       gss_mech_krb5)) {
1149                         return true;
1150                 }
1151         }
1152         if (feature & GENSEC_FEATURE_DCE_STYLE) {
1153                 return gensec_gssapi_state->gss_got_flags & GSS_C_DCE_STYLE;
1154         }
1155         if (feature & GENSEC_FEATURE_NEW_SPNEGO) {
1156                 NTSTATUS status;
1157                 uint32_t keytype;
1158
1159                 if (!(gensec_gssapi_state->gss_got_flags & GSS_C_INTEG_FLAG)) {
1160                         return false;
1161                 }
1162
1163                 if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "force_new_spnego", false)) {
1164                         return true;
1165                 }
1166                 if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "disable_new_spnego", false)) {
1167                         return false;
1168                 }
1169
1170                 status = gssapi_get_session_key(gensec_gssapi_state,
1171                                                 gensec_gssapi_state->gssapi_context, NULL, &keytype);
1172                 /*
1173                  * We should do a proper sig on the mechListMic unless
1174                  * we know we have to be backwards compatible with
1175                  * earlier windows versions.
1176                  *
1177                  * Negotiating a non-krb5
1178                  * mech for example should be regarded as having
1179                  * NEW_SPNEGO
1180                  */
1181                 if (NT_STATUS_IS_OK(status)) {
1182                         switch (keytype) {
1183                         case ENCTYPE_DES_CBC_CRC:
1184                         case ENCTYPE_DES_CBC_MD5:
1185                         case ENCTYPE_ARCFOUR_HMAC:
1186                         case ENCTYPE_DES3_CBC_SHA1:
1187                                 return false;
1188                         }
1189                 }
1190                 return true;
1191         }
1192         /* We can always do async (rather than strict request/reply) packets.  */
1193         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1194                 return true;
1195         }
1196         if (feature & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1197                 if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
1198                         return true;
1199                 }
1200
1201                 if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
1202                         return true;
1203                 }
1204
1205                 return false;
1206         }
1207         return false;
1208 }
1209
1210 static NTTIME gensec_gssapi_expire_time(struct gensec_security *gensec_security)
1211 {
1212         struct gensec_gssapi_state *gensec_gssapi_state =
1213                 talloc_get_type_abort(gensec_security->private_data,
1214                 struct gensec_gssapi_state);
1215
1216         return gensec_gssapi_state->expire_time;
1217 }
1218
1219 /*
1220  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1221  * (for encrypting some passwords).
1222  *
1223  * This breaks all the abstractions, but what do you expect...
1224  */
1225 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1226                                           TALLOC_CTX *mem_ctx,
1227                                           DATA_BLOB *session_key)
1228 {
1229         struct gensec_gssapi_state *gensec_gssapi_state
1230                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1231         return gssapi_get_session_key(mem_ctx, gensec_gssapi_state->gssapi_context, session_key, NULL);
1232 }
1233
1234 /* Get some basic (and authorization) information about the user on
1235  * this session.  This uses either the PAC (if present) or a local
1236  * database lookup */
1237 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1238                                            TALLOC_CTX *mem_ctx,
1239                                            struct auth_session_info **_session_info)
1240 {
1241         NTSTATUS nt_status;
1242         TALLOC_CTX *tmp_ctx;
1243         struct gensec_gssapi_state *gensec_gssapi_state
1244                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1245         struct auth_session_info *session_info = NULL;
1246         OM_uint32 maj_stat, min_stat;
1247         DATA_BLOB pac_blob, *pac_blob_ptr = NULL;
1248
1249         gss_buffer_desc name_token;
1250         char *principal_string;
1251
1252         tmp_ctx = talloc_named(mem_ctx, 0, "gensec_gssapi_session_info context");
1253         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
1254
1255         maj_stat = gss_display_name (&min_stat,
1256                                      gensec_gssapi_state->client_name,
1257                                      &name_token,
1258                                      NULL);
1259         if (GSS_ERROR(maj_stat)) {
1260                 DEBUG(1, ("GSS display_name failed: %s\n",
1261                           gssapi_error_string(tmp_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1262                 talloc_free(tmp_ctx);
1263                 return NT_STATUS_FOOBAR;
1264         }
1265
1266         principal_string = talloc_strndup(tmp_ctx,
1267                                           (const char *)name_token.value,
1268                                           name_token.length);
1269
1270         gss_release_buffer(&min_stat, &name_token);
1271
1272         if (!principal_string) {
1273                 talloc_free(tmp_ctx);
1274                 return NT_STATUS_NO_MEMORY;
1275         }
1276
1277         nt_status = gssapi_obtain_pac_blob(tmp_ctx,  gensec_gssapi_state->gssapi_context,
1278                                            gensec_gssapi_state->client_name,
1279                                            &pac_blob);
1280
1281         /* IF we have the PAC - otherwise we need to get this
1282          * data from elsewere - local ldb, or (TODO) lookup of some
1283          * kind...
1284          */
1285         if (NT_STATUS_IS_OK(nt_status)) {
1286                 pac_blob_ptr = &pac_blob;
1287         }
1288         nt_status = gensec_generate_session_info_pac(tmp_ctx,
1289                                                      gensec_security,
1290                                                      gensec_gssapi_state->smb_krb5_context,
1291                                                      pac_blob_ptr, principal_string,
1292                                                      gensec_get_remote_address(gensec_security),
1293                                                      &session_info);
1294         if (!NT_STATUS_IS_OK(nt_status)) {
1295                 talloc_free(tmp_ctx);
1296                 return nt_status;
1297         }
1298
1299         nt_status = gensec_gssapi_session_key(gensec_security, session_info, &session_info->session_key);
1300         if (!NT_STATUS_IS_OK(nt_status)) {
1301                 talloc_free(tmp_ctx);
1302                 return nt_status;
1303         }
1304
1305         if (gensec_gssapi_state->gss_got_flags & GSS_C_DELEG_FLAG &&
1306             gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
1307                 krb5_error_code ret;
1308                 const char *error_string;
1309
1310                 DEBUG(10, ("gensec_gssapi: delegated credentials supplied by client\n"));
1311                 session_info->credentials = cli_credentials_init(session_info);
1312                 if (!session_info->credentials) {
1313                         talloc_free(tmp_ctx);
1314                         return NT_STATUS_NO_MEMORY;
1315                 }
1316
1317                 cli_credentials_set_conf(session_info->credentials, gensec_security->settings->lp_ctx);
1318                 /* Just so we don't segfault trying to get at a username */
1319                 cli_credentials_set_anonymous(session_info->credentials);
1320
1321                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1322                                                            gensec_security->settings->lp_ctx,
1323                                                            gensec_gssapi_state->delegated_cred_handle,
1324                                                            CRED_SPECIFIED, &error_string);
1325                 if (ret) {
1326                         talloc_free(tmp_ctx);
1327                         DEBUG(2,("Failed to get gss creds: %s\n", error_string));
1328                         return NT_STATUS_NO_MEMORY;
1329                 }
1330
1331                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1332                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1333
1334                 /* It has been taken from this place... */
1335                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1336         } else {
1337                 DEBUG(10, ("gensec_gssapi: NO delegated credentials supplied by client\n"));
1338         }
1339
1340         *_session_info = talloc_steal(mem_ctx, session_info);
1341         talloc_free(tmp_ctx);
1342
1343         return NT_STATUS_OK;
1344 }
1345
1346 static size_t gensec_gssapi_sig_size(struct gensec_security *gensec_security, size_t data_size)
1347 {
1348         struct gensec_gssapi_state *gensec_gssapi_state
1349                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1350         size_t sig_size;
1351
1352         if (gensec_gssapi_state->sig_size > 0) {
1353                 return gensec_gssapi_state->sig_size;
1354         }
1355
1356         sig_size = gssapi_get_sig_size(gensec_gssapi_state->gssapi_context,
1357                                        gensec_gssapi_state->gss_oid,
1358                                        gensec_gssapi_state->gss_want_flags,
1359                                        data_size);
1360
1361         gensec_gssapi_state->sig_size = sig_size;
1362         return gensec_gssapi_state->sig_size;
1363 }
1364
1365 static const char *gensec_gssapi_krb5_oids[] = {
1366         GENSEC_OID_KERBEROS5_OLD,
1367         GENSEC_OID_KERBEROS5,
1368         NULL
1369 };
1370
1371 static const char *gensec_gssapi_spnego_oids[] = {
1372         GENSEC_OID_SPNEGO,
1373         NULL
1374 };
1375
1376 /* As a server, this could in theory accept any GSSAPI mech */
1377 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1378         .name           = "gssapi_spnego",
1379         .sasl_name      = "GSS-SPNEGO",
1380         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1381         .oid            = gensec_gssapi_spnego_oids,
1382         .client_start   = gensec_gssapi_client_start,
1383         .server_start   = gensec_gssapi_server_start,
1384         .magic          = gensec_magic_check_krb5_oid,
1385         .update         = gensec_gssapi_update,
1386         .session_key    = gensec_gssapi_session_key,
1387         .session_info   = gensec_gssapi_session_info,
1388         .sign_packet    = gensec_gssapi_sign_packet,
1389         .check_packet   = gensec_gssapi_check_packet,
1390         .seal_packet    = gensec_gssapi_seal_packet,
1391         .unseal_packet  = gensec_gssapi_unseal_packet,
1392         .max_input_size   = gensec_gssapi_max_input_size,
1393         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1394         .wrap           = gensec_gssapi_wrap,
1395         .unwrap         = gensec_gssapi_unwrap,
1396         .have_feature   = gensec_gssapi_have_feature,
1397         .expire_time    = gensec_gssapi_expire_time,
1398         .enabled        = false,
1399         .kerberos       = true,
1400         .priority       = GENSEC_GSSAPI
1401 };
1402
1403 /* As a server, this could in theory accept any GSSAPI mech */
1404 static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
1405         .name           = "gssapi_krb5",
1406         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1407         .oid            = gensec_gssapi_krb5_oids,
1408         .client_start   = gensec_gssapi_client_start,
1409         .server_start   = gensec_gssapi_server_start,
1410         .magic          = gensec_magic_check_krb5_oid,
1411         .update         = gensec_gssapi_update,
1412         .session_key    = gensec_gssapi_session_key,
1413         .session_info   = gensec_gssapi_session_info,
1414         .sig_size       = gensec_gssapi_sig_size,
1415         .sign_packet    = gensec_gssapi_sign_packet,
1416         .check_packet   = gensec_gssapi_check_packet,
1417         .seal_packet    = gensec_gssapi_seal_packet,
1418         .unseal_packet  = gensec_gssapi_unseal_packet,
1419         .max_input_size   = gensec_gssapi_max_input_size,
1420         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1421         .wrap           = gensec_gssapi_wrap,
1422         .unwrap         = gensec_gssapi_unwrap,
1423         .have_feature   = gensec_gssapi_have_feature,
1424         .expire_time    = gensec_gssapi_expire_time,
1425         .enabled        = true,
1426         .kerberos       = true,
1427         .priority       = GENSEC_GSSAPI
1428 };
1429
1430 /* As a server, this could in theory accept any GSSAPI mech */
1431 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1432         .name             = "gssapi_krb5_sasl",
1433         .sasl_name        = "GSSAPI",
1434         .client_start     = gensec_gssapi_sasl_client_start,
1435         .server_start     = gensec_gssapi_sasl_server_start,
1436         .update           = gensec_gssapi_update,
1437         .session_key      = gensec_gssapi_session_key,
1438         .session_info     = gensec_gssapi_session_info,
1439         .max_input_size   = gensec_gssapi_max_input_size,
1440         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1441         .wrap             = gensec_gssapi_wrap,
1442         .unwrap           = gensec_gssapi_unwrap,
1443         .have_feature     = gensec_gssapi_have_feature,
1444         .expire_time      = gensec_gssapi_expire_time,
1445         .enabled          = true,
1446         .kerberos         = true,
1447         .priority         = GENSEC_GSSAPI
1448 };
1449
1450 _PUBLIC_ NTSTATUS gensec_gssapi_init(void)
1451 {
1452         NTSTATUS ret;
1453
1454         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1455         if (!NT_STATUS_IS_OK(ret)) {
1456                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1457                         gensec_gssapi_spnego_security_ops.name));
1458                 return ret;
1459         }
1460
1461         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1462         if (!NT_STATUS_IS_OK(ret)) {
1463                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1464                         gensec_gssapi_krb5_security_ops.name));
1465                 return ret;
1466         }
1467
1468         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1469         if (!NT_STATUS_IS_OK(ret)) {
1470                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1471                         gensec_gssapi_sasl_krb5_security_ops.name));
1472                 return ret;
1473         }
1474
1475         return ret;
1476 }