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