source4/auth/gensec/gensec_gssapi.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Kerberos backend for GENSEC
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   7    Copyright (C) Stefan Metzmacher <metze@samba.org> 2004-2005
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "lib/events/events.h"
  26 #include "system/kerberos.h"
  27 #include "heimdal/lib/gssapi/gssapi/gssapi.h"
  28 #include "auth/kerberos/kerberos.h"
  29 #include "librpc/gen_ndr/krb5pac.h"
  30 #include "auth/auth.h"
  31 #include "lib/ldb/include/ldb.h"
  32 #include "auth/auth_sam.h"
  33 #include "librpc/rpc/dcerpc.h"
  34 #include "auth/credentials/credentials.h"
  35 #include "auth/credentials/credentials_krb5.h"
  36 #include "auth/gensec/gensec.h"
  37 #include "auth/gensec/gensec_proto.h"
  38 #include "param/param.h"
  39 #include "auth/session_proto.h"
  40
  41 enum gensec_gssapi_sasl_state
  42 {
  43         STAGE_GSS_NEG,
  44         STAGE_SASL_SSF_NEG,
  45         STAGE_SASL_SSF_ACCEPT,
  46         STAGE_DONE
  47 };
  48
  49 #define NEG_SEAL 0x4
  50 #define NEG_SIGN 0x2
  51 #define NEG_NONE 0x1
  52
  53 struct gensec_gssapi_state {
  54         gss_ctx_id_t gssapi_context;
  55         struct gss_channel_bindings_struct *input_chan_bindings;
  56         gss_name_t server_name;
  57         gss_name_t client_name;
  58         OM_uint32 want_flags, got_flags;
  59         gss_OID gss_oid;
  60
  61         DATA_BLOB session_key;
  62         DATA_BLOB pac;
  63
  64         struct smb_krb5_context *smb_krb5_context;
  65         struct gssapi_creds_container *client_cred;
  66         struct gssapi_creds_container *server_cred;
  67
  68         gss_cred_id_t delegated_cred_handle;
  69
  70         bool sasl; /* We have two different mechs in this file: One
  71                     * for SASL wrapped GSSAPI and another for normal
  72                     * GSSAPI */
  73         enum gensec_gssapi_sasl_state sasl_state;
  74         uint8_t sasl_protection; /* What was negotiated at the SASL
  75                                   * layer, independent of the GSSAPI
  76                                   * layer... */
  77
  78         size_t max_wrap_buf_size;
  79         int gss_exchange_count;
  80 };
  81
  82 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security);
  83 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security);
  84
  85 static char *gssapi_error_string(TALLOC_CTX *mem_ctx,
  86                                  OM_uint32 maj_stat, OM_uint32 min_stat,
  87                                  const gss_OID mech)
  88 {
  89         OM_uint32 disp_min_stat, disp_maj_stat;
  90         gss_buffer_desc maj_error_message;
  91         gss_buffer_desc min_error_message;
  92         char *maj_error_string, *min_error_string;
  93         OM_uint32 msg_ctx = 0;
  94
  95         char *ret;
  96
  97         maj_error_message.value = NULL;
  98         min_error_message.value = NULL;
  99         maj_error_message.length = 0;
 100         min_error_message.length = 0;
 101
 102         disp_maj_stat = gss_display_status(&disp_min_stat, maj_stat, GSS_C_GSS_CODE,
 103                            mech, &msg_ctx, &maj_error_message);
 104         disp_maj_stat = gss_display_status(&disp_min_stat, min_stat, GSS_C_MECH_CODE,
 105                            mech, &msg_ctx, &min_error_message);
 106
 107         maj_error_string = talloc_strndup(mem_ctx, (char *)maj_error_message.value, maj_error_message.length);
 108
 109         min_error_string = talloc_strndup(mem_ctx, (char *)min_error_message.value, min_error_message.length);
 110
 111         ret = talloc_asprintf(mem_ctx, "%s: %s", maj_error_string, min_error_string);
 112
 113         talloc_free(maj_error_string);
 114         talloc_free(min_error_string);
 115
 116         gss_release_buffer(&disp_min_stat, &maj_error_message);
 117         gss_release_buffer(&disp_min_stat, &min_error_message);
 118
 119         return ret;
 120 }
 121
 122
 123 static int gensec_gssapi_destructor(struct gensec_gssapi_state *gensec_gssapi_state)
 124 {
 125         OM_uint32 maj_stat, min_stat;
 126
 127         if (gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
 128                 maj_stat = gss_release_cred(&min_stat,
 129                                             &gensec_gssapi_state->delegated_cred_handle);
 130         }
 131
 132         if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
 133                 maj_stat = gss_delete_sec_context (&min_stat,
 134                                                    &gensec_gssapi_state->gssapi_context,
 135                                                    GSS_C_NO_BUFFER);
 136         }
 137
 138         if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
 139                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->server_name);
 140         }
 141         if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
 142                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->client_name);
 143         }
 144         return 0;
 145 }
 146
 147 static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 148 {
 149         struct gensec_gssapi_state *gensec_gssapi_state;
 150         krb5_error_code ret;
 151         struct gsskrb5_send_to_kdc send_to_kdc;
 152
 153         gensec_gssapi_state = talloc(gensec_security, struct gensec_gssapi_state);
 154         if (!gensec_gssapi_state) {
 155                 return NT_STATUS_NO_MEMORY;
 156         }
 157
 158         gensec_gssapi_state->gss_exchange_count = 0;
 159         gensec_gssapi_state->max_wrap_buf_size
 160                 = lp_parm_int(gensec_security->lp_ctx, NULL, "gensec_gssapi", "max wrap buf size", 65536);
 161
 162         gensec_gssapi_state->sasl = false;
 163         gensec_gssapi_state->sasl_state = STAGE_GSS_NEG;
 164
 165         gensec_security->private_data = gensec_gssapi_state;
 166
 167         gensec_gssapi_state->gssapi_context = GSS_C_NO_CONTEXT;
 168         gensec_gssapi_state->server_name = GSS_C_NO_NAME;
 169         gensec_gssapi_state->client_name = GSS_C_NO_NAME;
 170
 171         /* TODO: Fill in channel bindings */
 172         gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
 173
 174         gensec_gssapi_state->want_flags = 0;
 175         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "mutual", true)) {
 176                 gensec_gssapi_state->want_flags |= GSS_C_MUTUAL_FLAG;
 177         }
 178         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "delegation", true)) {
 179                 gensec_gssapi_state->want_flags |= GSS_C_DELEG_FLAG;
 180         }
 181         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "replay", true)) {
 182                 gensec_gssapi_state->want_flags |= GSS_C_REPLAY_FLAG;
 183         }
 184         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "sequence", true)) {
 185                 gensec_gssapi_state->want_flags |= GSS_C_SEQUENCE_FLAG;
 186         }
 187
 188         gensec_gssapi_state->got_flags = 0;
 189
 190         gensec_gssapi_state->session_key = data_blob(NULL, 0);
 191         gensec_gssapi_state->pac = data_blob(NULL, 0);
 192
 193         gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 194
 195         talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 196
 197         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 198                 gensec_gssapi_state->want_flags |= GSS_C_INTEG_FLAG;
 199         }
 200         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 201                 gensec_gssapi_state->want_flags |= GSS_C_CONF_FLAG;
 202         }
 203         if (gensec_security->want_features & GENSEC_FEATURE_DCE_STYLE) {
 204                 gensec_gssapi_state->want_flags |= GSS_C_DCE_STYLE;
 205         }
 206
 207         gensec_gssapi_state->gss_oid = GSS_C_NULL_OID;
 208
 209         send_to_kdc.func = smb_krb5_send_and_recv_func;
 210         send_to_kdc.ptr = gensec_security->event_ctx;
 211
 212         ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
 213         if (ret) {
 214                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 215                 talloc_free(gensec_gssapi_state);
 216                 return NT_STATUS_INTERNAL_ERROR;
 217         }
 218         if (lp_realm(gensec_security->lp_ctx) && *lp_realm(gensec_security->lp_ctx)) {
 219                 char *upper_realm = strupper_talloc(gensec_gssapi_state, lp_realm(gensec_security->lp_ctx));
 220                 if (!upper_realm) {
 221                         DEBUG(1,("gensec_krb5_start: could not uppercase realm: %s\n", lp_realm(gensec_security->lp_ctx)));
 222                         talloc_free(gensec_gssapi_state);
 223                         return NT_STATUS_NO_MEMORY;
 224                 }
 225                 ret = gsskrb5_set_default_realm(upper_realm);
 226                 talloc_free(upper_realm);
 227                 if (ret) {
 228                         DEBUG(1,("gensec_krb5_start: gsskrb5_set_default_realm failed\n"));
 229                         talloc_free(gensec_gssapi_state);
 230                         return NT_STATUS_INTERNAL_ERROR;
 231                 }
 232         }
 233
 234         /* don't do DNS lookups of any kind, it might/will fail for a netbios name */
 235         ret = gsskrb5_set_dns_canonicalize(lp_parm_bool(gensec_security->lp_ctx, NULL, "krb5", "set_dns_canonicalize", false));
 236         if (ret) {
 237                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_dns_canonicalize failed\n"));
 238                 talloc_free(gensec_gssapi_state);
 239                 return NT_STATUS_INTERNAL_ERROR;
 240         }
 241
 242         ret = smb_krb5_init_context(gensec_gssapi_state,
 243                                     gensec_security->event_ctx,
 244                                     gensec_security->lp_ctx,
 245                                     &gensec_gssapi_state->smb_krb5_context);
 246         if (ret) {
 247                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n",
 248                          error_message(ret)));
 249                 talloc_free(gensec_gssapi_state);
 250                 return NT_STATUS_INTERNAL_ERROR;
 251         }
 252         return NT_STATUS_OK;
 253 }
 254
 255 static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
 256 {
 257         NTSTATUS nt_status;
 258         int ret;
 259         struct gensec_gssapi_state *gensec_gssapi_state;
 260         struct cli_credentials *machine_account;
 261         struct gssapi_creds_container *gcc;
 262
 263         nt_status = gensec_gssapi_start(gensec_security);
 264         if (!NT_STATUS_IS_OK(nt_status)) {
 265                 return nt_status;
 266         }
 267
 268         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 269
 270         machine_account = gensec_get_credentials(gensec_security);
 271
 272         if (!machine_account) {
 273                 DEBUG(3, ("No machine account credentials specified\n"));
 274                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 275         } else {
 276                 ret = cli_credentials_get_server_gss_creds(machine_account,
 277                                                            gensec_security->event_ctx,
 278                                                            gensec_security->lp_ctx, &gcc);
 279                 if (ret) {
 280                         DEBUG(1, ("Aquiring acceptor credentials failed: %s\n",
 281                                   error_message(ret)));
 282                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 283                 }
 284         }
 285
 286         gensec_gssapi_state->server_cred = gcc;
 287         return NT_STATUS_OK;
 288
 289 }
 290
 291 static NTSTATUS gensec_gssapi_sasl_server_start(struct gensec_security *gensec_security)
 292 {
 293         NTSTATUS nt_status;
 294         struct gensec_gssapi_state *gensec_gssapi_state;
 295         nt_status = gensec_gssapi_server_start(gensec_security);
 296
 297         if (NT_STATUS_IS_OK(nt_status)) {
 298                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 299                 gensec_gssapi_state->sasl = true;
 300         }
 301         return nt_status;
 302 }
 303
 304 static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
 305 {
 306         struct gensec_gssapi_state *gensec_gssapi_state;
 307         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 308         krb5_error_code ret;
 309         NTSTATUS nt_status;
 310         gss_buffer_desc name_token;
 311         gss_OID name_type;
 312         OM_uint32 maj_stat, min_stat;
 313         const char *hostname = gensec_get_target_hostname(gensec_security);
 314         const char *principal;
 315         struct gssapi_creds_container *gcc;
 316
 317         if (!hostname) {
 318                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 319                 return NT_STATUS_INVALID_PARAMETER;
 320         }
 321         if (is_ipaddress(hostname)) {
 322                 DEBUG(2, ("Cannot do GSSAPI to an IP address\n"));
 323                 return NT_STATUS_INVALID_PARAMETER;
 324         }
 325         if (strcmp(hostname, "localhost") == 0) {
 326                 DEBUG(2, ("GSSAPI to 'localhost' does not make sense\n"));
 327                 return NT_STATUS_INVALID_PARAMETER;
 328         }
 329
 330         nt_status = gensec_gssapi_start(gensec_security);
 331         if (!NT_STATUS_IS_OK(nt_status)) {
 332                 return nt_status;
 333         }
 334
 335         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 336
 337         gensec_gssapi_state->gss_oid = gss_mech_krb5;
 338
 339         principal = gensec_get_target_principal(gensec_security);
 340         if (principal && lp_client_use_spnego_principal(gensec_security->lp_ctx)) {
 341                 name_type = GSS_C_NULL_OID;
 342         } else {
 343                 principal = talloc_asprintf(gensec_gssapi_state, "%s@%s",
 344                                             gensec_get_target_service(gensec_security),
 345                                             hostname);
 346
 347                 name_type = GSS_C_NT_HOSTBASED_SERVICE;
 348         }
 349         name_token.value  = discard_const_p(uint8_t, principal);
 350         name_token.length = strlen(principal);
 351
 352
 353         maj_stat = gss_import_name (&min_stat,
 354                                     &name_token,
 355                                     name_type,
 356                                     &gensec_gssapi_state->server_name);
 357         if (maj_stat) {
 358                 DEBUG(2, ("GSS Import name of %s failed: %s\n",
 359                           (char *)name_token.value,
 360                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 361                 return NT_STATUS_INVALID_PARAMETER;
 362         }
 363
 364         ret = cli_credentials_get_client_gss_creds(creds,
 365                                                    gensec_security->event_ctx,
 366                                                    gensec_security->lp_ctx, &gcc);
 367         switch (ret) {
 368         case 0:
 369                 break;
 370         case KRB5KDC_ERR_PREAUTH_FAILED:
 371                 return NT_STATUS_LOGON_FAILURE;
 372         case KRB5_KDC_UNREACH:
 373                 DEBUG(3, ("Cannot reach a KDC we require to contact %s\n", principal));
 374                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 375         default:
 376                 DEBUG(1, ("Aquiring initiator credentials failed\n"));
 377                 return NT_STATUS_UNSUCCESSFUL;
 378         }
 379
 380         gensec_gssapi_state->client_cred = gcc;
 381         if (!talloc_reference(gensec_gssapi_state, gcc)) {
 382                 return NT_STATUS_NO_MEMORY;
 383         }
 384
 385         return NT_STATUS_OK;
 386 }
 387
 388 static NTSTATUS gensec_gssapi_sasl_client_start(struct gensec_security *gensec_security)
 389 {
 390         NTSTATUS nt_status;
 391         struct gensec_gssapi_state *gensec_gssapi_state;
 392         nt_status = gensec_gssapi_client_start(gensec_security);
 393
 394         if (NT_STATUS_IS_OK(nt_status)) {
 395                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 396                 gensec_gssapi_state->sasl = true;
 397         }
 398         return nt_status;
 399 }
 400
 401
 402 /**
 403  * Check if the packet is one for this mechansim
 404  *
 405  * @param gensec_security GENSEC state
 406  * @param in The request, as a DATA_BLOB
 407  * @return Error, INVALID_PARAMETER if it's not a packet for us
 408  *                or NT_STATUS_OK if the packet is ok.
 409  */
 410
 411 static NTSTATUS gensec_gssapi_magic(struct gensec_security *gensec_security,
 412                                     const DATA_BLOB *in)
 413 {
 414         if (gensec_gssapi_check_oid(in, GENSEC_OID_KERBEROS5)) {
 415                 return NT_STATUS_OK;
 416         } else {
 417                 return NT_STATUS_INVALID_PARAMETER;
 418         }
 419 }
 420
 421
 422 /**
 423  * Next state function for the GSSAPI GENSEC mechanism
 424  *
 425  * @param gensec_gssapi_state GSSAPI State
 426  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 427  * @param in The request, as a DATA_BLOB
 428  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 429  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 430  *                or NT_STATUS_OK if the user is authenticated.
 431  */
 432
 433 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 434                                    TALLOC_CTX *out_mem_ctx,
 435                                    const DATA_BLOB in, DATA_BLOB *out)
 436 {
 437         struct gensec_gssapi_state *gensec_gssapi_state
 438                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 439         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 440         OM_uint32 maj_stat, min_stat;
 441         OM_uint32 min_stat2;
 442         gss_buffer_desc input_token, output_token;
 443         gss_OID gss_oid_p = NULL;
 444         input_token.length = in.length;
 445         input_token.value = in.data;
 446
 447         switch (gensec_gssapi_state->sasl_state) {
 448         case STAGE_GSS_NEG:
 449         {
 450                 switch (gensec_security->gensec_role) {
 451                 case GENSEC_CLIENT:
 452                 {
 453                         maj_stat = gss_init_sec_context(&min_stat,
 454                                                         gensec_gssapi_state->client_cred->creds,
 455                                                         &gensec_gssapi_state->gssapi_context,
 456                                                         gensec_gssapi_state->server_name,
 457                                                         gensec_gssapi_state->gss_oid,
 458                                                         gensec_gssapi_state->want_flags,
 459                                                         0,
 460                                                         gensec_gssapi_state->input_chan_bindings,
 461                                                         &input_token,
 462                                                         &gss_oid_p,
 463                                                         &output_token,
 464                                                         &gensec_gssapi_state->got_flags, /* ret flags */
 465                                                         NULL);
 466                         if (gss_oid_p) {
 467                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 468                         }
 469                         break;
 470                 }
 471                 case GENSEC_SERVER:
 472                 {
 473                         maj_stat = gss_accept_sec_context(&min_stat,
 474                                                           &gensec_gssapi_state->gssapi_context,
 475                                                           gensec_gssapi_state->server_cred->creds,
 476                                                           &input_token,
 477                                                           gensec_gssapi_state->input_chan_bindings,
 478                                                           &gensec_gssapi_state->client_name,
 479                                                           &gss_oid_p,
 480                                                           &output_token,
 481                                                           &gensec_gssapi_state->got_flags,
 482                                                           NULL,
 483                                                           &gensec_gssapi_state->delegated_cred_handle);
 484                         if (gss_oid_p) {
 485                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 486                         }
 487                         break;
 488                 }
 489                 default:
 490                         return NT_STATUS_INVALID_PARAMETER;
 491
 492                 }
 493
 494                 gensec_gssapi_state->gss_exchange_count++;
 495
 496                 if (maj_stat == GSS_S_COMPLETE) {
 497                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 498                         gss_release_buffer(&min_stat2, &output_token);
 499
 500                         if (gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG) {
 501                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 502                         } else {
 503                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 504                         }
 505
 506                         /* We may have been invoked as SASL, so there
 507                          * is more work to do */
 508                         if (gensec_gssapi_state->sasl) {
 509                                 /* Due to a very subtle interaction
 510                                  * with SASL and the LDAP libs, we
 511                                  * must ensure the data pointer is
 512                                  * != NULL, but the length is 0.
 513                                  *
 514                                  * This ensures we send a 'zero
 515                                  * length' (rather than NULL) response
 516                                  */
 517
 518                                 if (!out->data) {
 519                                         out->data = (uint8_t *)talloc_strdup(out_mem_ctx, "\0");
 520                                 }
 521
 522                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 523                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 524                         } else {
 525                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 526
 527                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 528                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly sealed\n"));
 529                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 530                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly signed\n"));
 531                                 } else {
 532                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 533                                 }
 534
 535                                 return NT_STATUS_OK;
 536                         }
 537                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 538                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 539                         gss_release_buffer(&min_stat2, &output_token);
 540
 541                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 542                 } else if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
 543                         switch (min_stat) {
 544                         case KRB5_KDC_UNREACH:
 545                                 DEBUG(3, ("Cannot reach a KDC we require: %s\n",
 546                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 547                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 548                         case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 549                                 DEBUG(3, ("Server is not registered with our KDC: %s\n",
 550                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 551                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 552                         case KRB5KRB_AP_ERR_MSG_TYPE:
 553                                 /* garbage input, possibly from the auto-mech detection */
 554                                 return NT_STATUS_INVALID_PARAMETER;
 555                         default:
 556                                 DEBUG(1, ("GSS Update(krb5)(%d) Update failed: %s\n",
 557                                           gensec_gssapi_state->gss_exchange_count,
 558                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 559                                 return nt_status;
 560                         }
 561                 } else {
 562                         DEBUG(1, ("GSS Update(%d) failed: %s\n",
 563                                   gensec_gssapi_state->gss_exchange_count,
 564                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 565                         return nt_status;
 566                 }
 567                 break;
 568         }
 569
 570         /* These last two stages are only done if we were invoked as SASL */
 571         case STAGE_SASL_SSF_NEG:
 572         {
 573                 switch (gensec_security->gensec_role) {
 574                 case GENSEC_CLIENT:
 575                 {
 576                         uint8_t maxlength_proposed[4];
 577                         uint8_t maxlength_accepted[4];
 578                         uint8_t security_supported;
 579                         int conf_state;
 580                         gss_qop_t qop_state;
 581                         input_token.length = in.length;
 582                         input_token.value = in.data;
 583
 584                         /* As a client, we have just send a
 585                          * zero-length blob to the server (after the
 586                          * normal GSSAPI exchange), and it has replied
 587                          * with it's SASL negotiation */
 588
 589                         maj_stat = gss_unwrap(&min_stat,
 590                                               gensec_gssapi_state->gssapi_context,
 591                                               &input_token,
 592                                               &output_token,
 593                                               &conf_state,
 594                                               &qop_state);
 595                         if (GSS_ERROR(maj_stat)) {
 596                                 DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 597                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 598                                 return NT_STATUS_ACCESS_DENIED;
 599                         }
 600
 601                         if (output_token.length < 4) {
 602                                 return NT_STATUS_INVALID_PARAMETER;
 603                         }
 604
 605                         memcpy(maxlength_proposed, output_token.value, 4);
 606                         gss_release_buffer(&min_stat, &output_token);
 607
 608                         /* first byte is the proposed security */
 609                         security_supported = maxlength_proposed[0];
 610                         maxlength_proposed[0] = '\0';
 611
 612                         /* Rest is the proposed max wrap length */
 613                         gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_proposed, 0),
 614                                                                      gensec_gssapi_state->max_wrap_buf_size);
 615                         gensec_gssapi_state->sasl_protection = 0;
 616                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 617                                 if (security_supported & NEG_SEAL) {
 618                                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 619                                 }
 620                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 621                                 if (security_supported & NEG_SIGN) {
 622                                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 623                                 }
 624                         } else if (security_supported & NEG_NONE) {
 625                                 gensec_gssapi_state->sasl_protection |= NEG_NONE;
 626                         } else {
 627                                 DEBUG(1, ("Remote server does not support unprotected connections"));
 628                                 return NT_STATUS_ACCESS_DENIED;
 629                         }
 630
 631                         /* Send back the negotiated max length */
 632
 633                         RSIVAL(maxlength_accepted, 0, gensec_gssapi_state->max_wrap_buf_size);
 634
 635                         maxlength_accepted[0] = gensec_gssapi_state->sasl_protection;
 636
 637                         input_token.value = maxlength_accepted;
 638                         input_token.length = sizeof(maxlength_accepted);
 639
 640                         maj_stat = gss_wrap(&min_stat,
 641                                             gensec_gssapi_state->gssapi_context,
 642                                             false,
 643                                             GSS_C_QOP_DEFAULT,
 644                                             &input_token,
 645                                             &conf_state,
 646                                             &output_token);
 647                         if (GSS_ERROR(maj_stat)) {
 648                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 649                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 650                                 return NT_STATUS_ACCESS_DENIED;
 651                         }
 652
 653                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 654                         gss_release_buffer(&min_stat, &output_token);
 655
 656                         /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 657                         gensec_gssapi_state->sasl_state = STAGE_DONE;
 658
 659                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 660                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly sealed\n"));
 661                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 662                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly signed\n"));
 663                         } else {
 664                                 DEBUG(3, ("SASL/GSSAPI Connection to server will have no cryptographicly protection\n"));
 665                         }
 666
 667                         return NT_STATUS_OK;
 668                 }
 669                 case GENSEC_SERVER:
 670                 {
 671                         uint8_t maxlength_proposed[4];
 672                         uint8_t security_supported = 0x0;
 673                         int conf_state;
 674
 675                         /* As a server, we have just been sent a zero-length blob (note this, but it isn't fatal) */
 676                         if (in.length != 0) {
 677                                 DEBUG(1, ("SASL/GSSAPI: client sent non-zero length starting SASL negotiation!\n"));
 678                         }
 679
 680                         /* Give the client some idea what we will support */
 681
 682                         RSIVAL(maxlength_proposed, 0, gensec_gssapi_state->max_wrap_buf_size);
 683                         /* first byte is the proposed security */
 684                         maxlength_proposed[0] = '\0';
 685
 686                         gensec_gssapi_state->sasl_protection = 0;
 687                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 688                                 security_supported |= NEG_SEAL;
 689                         }
 690                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 691                                 security_supported |= NEG_SIGN;
 692                         }
 693                         if (security_supported == 0) {
 694                                 /* If we don't support anything, this must be 0 */
 695                                 RSIVAL(maxlength_proposed, 0, 0x0);
 696                         }
 697
 698                         /* TODO:  We may not wish to support this */
 699                         security_supported |= NEG_NONE;
 700                         maxlength_proposed[0] = security_supported;
 701
 702                         input_token.value = maxlength_proposed;
 703                         input_token.length = sizeof(maxlength_proposed);
 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                         gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_ACCEPT;
 722                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 723                 }
 724                 default:
 725                         return NT_STATUS_INVALID_PARAMETER;
 726
 727                 }
 728         }
 729         /* This is s server-only stage */
 730         case STAGE_SASL_SSF_ACCEPT:
 731         {
 732                 uint8_t maxlength_accepted[4];
 733                 uint8_t security_accepted;
 734                 int conf_state;
 735                 gss_qop_t qop_state;
 736                 input_token.length = in.length;
 737                 input_token.value = in.data;
 738
 739                 maj_stat = gss_unwrap(&min_stat,
 740                                       gensec_gssapi_state->gssapi_context,
 741                                       &input_token,
 742                                       &output_token,
 743                                       &conf_state,
 744                                       &qop_state);
 745                 if (GSS_ERROR(maj_stat)) {
 746                         DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 747                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 748                         return NT_STATUS_ACCESS_DENIED;
 749                 }
 750
 751                 if (output_token.length < 4) {
 752                         return NT_STATUS_INVALID_PARAMETER;
 753                 }
 754
 755                 memcpy(maxlength_accepted, output_token.value, 4);
 756                 gss_release_buffer(&min_stat, &output_token);
 757
 758                 /* first byte is the proposed security */
 759                 security_accepted = maxlength_accepted[0];
 760                 maxlength_accepted[0] = '\0';
 761
 762                 /* Rest is the proposed max wrap length */
 763                 gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_accepted, 0),
 764                                                              gensec_gssapi_state->max_wrap_buf_size);
 765
 766                 gensec_gssapi_state->sasl_protection = 0;
 767                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 768                         if (security_accepted & NEG_SEAL) {
 769                                 gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 770                         }
 771                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 772                         if (security_accepted & NEG_SIGN) {
 773                                 gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 774                         }
 775                 } else if (security_accepted & NEG_NONE) {
 776                         gensec_gssapi_state->sasl_protection |= NEG_NONE;
 777                 } else {
 778                         DEBUG(1, ("Remote client does not support unprotected connections, but we failed to negotiate anything better"));
 779                         return NT_STATUS_ACCESS_DENIED;
 780                 }
 781
 782                 /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 783                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 784                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 785                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly sealed\n"));
 786                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 787                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly signed\n"));
 788                 } else {
 789                         DEBUG(5, ("SASL/GSSAPI Connection from client will have no cryptographic protection\n"));
 790                 }
 791
 792                 *out = data_blob(NULL, 0);
 793                 return NT_STATUS_OK;
 794         }
 795         default:
 796                 return NT_STATUS_INVALID_PARAMETER;
 797         }
 798 }
 799
 800 static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security,
 801                                    TALLOC_CTX *mem_ctx,
 802                                    const DATA_BLOB *in,
 803                                    DATA_BLOB *out)
 804 {
 805         struct gensec_gssapi_state *gensec_gssapi_state
 806                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 807         OM_uint32 maj_stat, min_stat;
 808         gss_buffer_desc input_token, output_token;
 809         int conf_state;
 810         input_token.length = in->length;
 811         input_token.value = in->data;
 812
 813         maj_stat = gss_wrap(&min_stat,
 814                             gensec_gssapi_state->gssapi_context,
 815                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 816                             GSS_C_QOP_DEFAULT,
 817                             &input_token,
 818                             &conf_state,
 819                             &output_token);
 820         if (GSS_ERROR(maj_stat)) {
 821                 DEBUG(1, ("gensec_gssapi_wrap: GSS Wrap failed: %s\n",
 822                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 823                 return NT_STATUS_ACCESS_DENIED;
 824         }
 825
 826         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 827         gss_release_buffer(&min_stat, &output_token);
 828
 829         if (gensec_gssapi_state->sasl) {
 830                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 831                 if (max_wrapped_size < out->length) {
 832                         DEBUG(1, ("gensec_gssapi_wrap: when wrapped, INPUT data (%u) is grew to be larger than SASL negotiated maximum output size (%u > %u)\n",
 833                                   (unsigned)in->length,
 834                                   (unsigned)out->length,
 835                                   (unsigned int)max_wrapped_size));
 836                         return NT_STATUS_INVALID_PARAMETER;
 837                 }
 838         }
 839
 840         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 841             && !conf_state) {
 842                 return NT_STATUS_ACCESS_DENIED;
 843         }
 844         return NT_STATUS_OK;
 845 }
 846
 847 static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security,
 848                                      TALLOC_CTX *mem_ctx,
 849                                      const DATA_BLOB *in,
 850                                      DATA_BLOB *out)
 851 {
 852         struct gensec_gssapi_state *gensec_gssapi_state
 853                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 854         OM_uint32 maj_stat, min_stat;
 855         gss_buffer_desc input_token, output_token;
 856         int conf_state;
 857         gss_qop_t qop_state;
 858         input_token.length = in->length;
 859         input_token.value = in->data;
 860
 861         if (gensec_gssapi_state->sasl) {
 862                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 863                 if (max_wrapped_size < in->length) {
 864                         DEBUG(1, ("gensec_gssapi_unwrap: WRAPPED data is larger than SASL negotiated maximum size\n"));
 865                         return NT_STATUS_INVALID_PARAMETER;
 866                 }
 867         }
 868
 869         maj_stat = gss_unwrap(&min_stat,
 870                               gensec_gssapi_state->gssapi_context,
 871                               &input_token,
 872                               &output_token,
 873                               &conf_state,
 874                               &qop_state);
 875         if (GSS_ERROR(maj_stat)) {
 876                 DEBUG(1, ("gensec_gssapi_unwrap: GSS UnWrap failed: %s\n",
 877                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 878                 return NT_STATUS_ACCESS_DENIED;
 879         }
 880
 881         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 882         gss_release_buffer(&min_stat, &output_token);
 883
 884         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 885             && !conf_state) {
 886                 return NT_STATUS_ACCESS_DENIED;
 887         }
 888         return NT_STATUS_OK;
 889 }
 890
 891 /* Find out the maximum input size negotiated on this connection */
 892
 893 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security)
 894 {
 895         struct gensec_gssapi_state *gensec_gssapi_state
 896                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 897         OM_uint32 maj_stat, min_stat;
 898         OM_uint32 max_input_size;
 899
 900         maj_stat = gss_wrap_size_limit(&min_stat,
 901                                        gensec_gssapi_state->gssapi_context,
 902                                        gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 903                                        GSS_C_QOP_DEFAULT,
 904                                        gensec_gssapi_state->max_wrap_buf_size,
 905                                        &max_input_size);
 906         if (GSS_ERROR(maj_stat)) {
 907                 TALLOC_CTX *mem_ctx = talloc_new(NULL);
 908                 DEBUG(1, ("gensec_gssapi_max_input_size: determinaing signature size with gss_wrap_size_limit failed: %s\n",
 909                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 910                 talloc_free(mem_ctx);
 911                 return 0;
 912         }
 913
 914         return max_input_size;
 915 }
 916
 917 /* Find out the maximum output size negotiated on this connection */
 918 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security)
 919 {
 920         struct gensec_gssapi_state *gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);;
 921         return gensec_gssapi_state->max_wrap_buf_size;
 922 }
 923
 924 static NTSTATUS gensec_gssapi_seal_packet(struct gensec_security *gensec_security,
 925                                           TALLOC_CTX *mem_ctx,
 926                                           uint8_t *data, size_t length,
 927                                           const uint8_t *whole_pdu, size_t pdu_length,
 928                                           DATA_BLOB *sig)
 929 {
 930         struct gensec_gssapi_state *gensec_gssapi_state
 931                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 932         OM_uint32 maj_stat, min_stat;
 933         gss_buffer_desc input_token, output_token;
 934         int conf_state;
 935         ssize_t sig_length;
 936
 937         input_token.length = length;
 938         input_token.value = data;
 939
 940         maj_stat = gss_wrap(&min_stat,
 941                             gensec_gssapi_state->gssapi_context,
 942                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 943                             GSS_C_QOP_DEFAULT,
 944                             &input_token,
 945                             &conf_state,
 946                             &output_token);
 947         if (GSS_ERROR(maj_stat)) {
 948                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap failed: %s\n",
 949                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 950                 return NT_STATUS_ACCESS_DENIED;
 951         }
 952
 953         if (output_token.length < input_token.length) {
 954                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
 955                           (long)output_token.length, (long)length));
 956                 return NT_STATUS_INTERNAL_ERROR;
 957         }
 958         sig_length = output_token.length - input_token.length;
 959
 960         memcpy(data, ((uint8_t *)output_token.value) + sig_length, length);
 961         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
 962
 963         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
 964         dump_data_pw("gensec_gssapi_seal_packet: clear\n", data, length);
 965         dump_data_pw("gensec_gssapi_seal_packet: sealed\n", ((uint8_t *)output_token.value) + sig_length, output_token.length - sig_length);
 966
 967         gss_release_buffer(&min_stat, &output_token);
 968
 969         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 970             && !conf_state) {
 971                 return NT_STATUS_ACCESS_DENIED;
 972         }
 973         return NT_STATUS_OK;
 974 }
 975
 976 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
 977                                             TALLOC_CTX *mem_ctx,
 978                                             uint8_t *data, size_t length,
 979                                             const uint8_t *whole_pdu, size_t pdu_length,
 980                                             const DATA_BLOB *sig)
 981 {
 982         struct gensec_gssapi_state *gensec_gssapi_state
 983                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 984         OM_uint32 maj_stat, min_stat;
 985         gss_buffer_desc input_token, output_token;
 986         int conf_state;
 987         gss_qop_t qop_state;
 988         DATA_BLOB in;
 989
 990         dump_data_pw("gensec_gssapi_unseal_packet: sig\n", sig->data, sig->length);
 991
 992         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
 993
 994         memcpy(in.data, sig->data, sig->length);
 995         memcpy(in.data + sig->length, data, length);
 996
 997         input_token.length = in.length;
 998         input_token.value = in.data;
 999
1000         maj_stat = gss_unwrap(&min_stat,
1001                               gensec_gssapi_state->gssapi_context,
1002                               &input_token,
1003                               &output_token,
1004                               &conf_state,
1005                               &qop_state);
1006         if (GSS_ERROR(maj_stat)) {
1007                 DEBUG(1, ("gensec_gssapi_unseal_packet: GSS UnWrap failed: %s\n",
1008                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1009                 return NT_STATUS_ACCESS_DENIED;
1010         }
1011
1012         if (output_token.length != length) {
1013                 return NT_STATUS_INTERNAL_ERROR;
1014         }
1015
1016         memcpy(data, output_token.value, length);
1017
1018         gss_release_buffer(&min_stat, &output_token);
1019
1020         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1021             && !conf_state) {
1022                 return NT_STATUS_ACCESS_DENIED;
1023         }
1024         return NT_STATUS_OK;
1025 }
1026
1027 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1028                                           TALLOC_CTX *mem_ctx,
1029                                           const uint8_t *data, size_t length,
1030                                           const uint8_t *whole_pdu, size_t pdu_length,
1031                                           DATA_BLOB *sig)
1032 {
1033         struct gensec_gssapi_state *gensec_gssapi_state
1034                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1035         OM_uint32 maj_stat, min_stat;
1036         gss_buffer_desc input_token, output_token;
1037         int conf_state;
1038         ssize_t sig_length = 0;
1039
1040         input_token.length = length;
1041         input_token.value = discard_const_p(uint8_t *, data);
1042
1043         maj_stat = gss_wrap(&min_stat,
1044                             gensec_gssapi_state->gssapi_context,
1045                             0,
1046                             GSS_C_QOP_DEFAULT,
1047                             &input_token,
1048                             &conf_state,
1049                             &output_token);
1050         if (GSS_ERROR(maj_stat)) {
1051                 DEBUG(1, ("GSS Wrap failed: %s\n",
1052                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1053                 return NT_STATUS_ACCESS_DENIED;
1054         }
1055
1056         if (output_token.length < input_token.length) {
1057                 DEBUG(1, ("gensec_gssapi_sign_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
1058                           (long)output_token.length, (long)length));
1059                 return NT_STATUS_INTERNAL_ERROR;
1060         }
1061
1062         /* Caller must pad to right boundary */
1063         sig_length = output_token.length - input_token.length;
1064
1065         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
1066
1067         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1068
1069         gss_release_buffer(&min_stat, &output_token);
1070
1071         return NT_STATUS_OK;
1072 }
1073
1074 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1075                                            TALLOC_CTX *mem_ctx,
1076                                            const uint8_t *data, size_t length,
1077                                            const uint8_t *whole_pdu, size_t pdu_length,
1078                                            const DATA_BLOB *sig)
1079 {
1080         struct gensec_gssapi_state *gensec_gssapi_state
1081                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1082         OM_uint32 maj_stat, min_stat;
1083         gss_buffer_desc input_token, output_token;
1084         int conf_state;
1085         gss_qop_t qop_state;
1086         DATA_BLOB in;
1087
1088         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1089
1090         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
1091
1092         memcpy(in.data, sig->data, sig->length);
1093         memcpy(in.data + sig->length, data, length);
1094
1095         input_token.length = in.length;
1096         input_token.value = in.data;
1097
1098         maj_stat = gss_unwrap(&min_stat,
1099                               gensec_gssapi_state->gssapi_context,
1100                               &input_token,
1101                               &output_token,
1102                               &conf_state,
1103                               &qop_state);
1104         if (GSS_ERROR(maj_stat)) {
1105                 DEBUG(1, ("GSS UnWrap failed: %s\n",
1106                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1107                 return NT_STATUS_ACCESS_DENIED;
1108         }
1109
1110         if (output_token.length != length) {
1111                 return NT_STATUS_INTERNAL_ERROR;
1112         }
1113
1114         gss_release_buffer(&min_stat, &output_token);
1115
1116         return NT_STATUS_OK;
1117 }
1118
1119 /* Try to figure out what features we actually got on the connection */
1120 static bool gensec_gssapi_have_feature(struct gensec_security *gensec_security,
1121                                        uint32_t feature)
1122 {
1123         struct gensec_gssapi_state *gensec_gssapi_state
1124                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1125         if (feature & GENSEC_FEATURE_SIGN) {
1126                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1127                 if (gensec_gssapi_state->sasl
1128                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1129                         return ((gensec_gssapi_state->sasl_protection & NEG_SIGN)
1130                                 && (gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG));
1131                 }
1132                 return gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG;
1133         }
1134         if (feature & GENSEC_FEATURE_SEAL) {
1135                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1136                 if (gensec_gssapi_state->sasl
1137                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1138                         return ((gensec_gssapi_state->sasl_protection & NEG_SEAL)
1139                                  && (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG));
1140                 }
1141                 return gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG;
1142         }
1143         if (feature & GENSEC_FEATURE_SESSION_KEY) {
1144                 /* Only for GSSAPI/Krb5 */
1145                 if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
1146                         return true;
1147                 }
1148         }
1149         if (feature & GENSEC_FEATURE_DCE_STYLE) {
1150                 return gensec_gssapi_state->got_flags & GSS_C_DCE_STYLE;
1151         }
1152         /* We can always do async (rather than strict request/reply) packets.  */
1153         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1154                 return true;
1155         }
1156         return false;
1157 }
1158
1159 /*
1160  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1161  * (for encrypting some passwords).
1162  *
1163  * This breaks all the abstractions, but what do you expect...
1164  */
1165 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1166                                           DATA_BLOB *session_key)
1167 {
1168         struct gensec_gssapi_state *gensec_gssapi_state
1169                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1170         OM_uint32 maj_stat, min_stat;
1171         krb5_keyblock *subkey;
1172
1173         if (gensec_gssapi_state->session_key.data) {
1174                 *session_key = gensec_gssapi_state->session_key;
1175                 return NT_STATUS_OK;
1176         }
1177
1178         maj_stat = gsskrb5_get_initiator_subkey(&min_stat,
1179                                                 gensec_gssapi_state->gssapi_context,
1180                                                 &subkey);
1181         if (maj_stat != 0) {
1182                 DEBUG(1, ("NO session key for this mech\n"));
1183                 return NT_STATUS_NO_USER_SESSION_KEY;
1184         }
1185
1186         DEBUG(10, ("Got KRB5 session key of length %d\n",
1187                    (int)KRB5_KEY_LENGTH(subkey)));
1188         gensec_gssapi_state->session_key = data_blob_talloc(gensec_gssapi_state,
1189                                                             KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
1190         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context, subkey);
1191         *session_key = gensec_gssapi_state->session_key;
1192         dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
1193
1194         return NT_STATUS_OK;
1195 }
1196
1197 /* Get some basic (and authorization) information about the user on
1198  * this session.  This uses either the PAC (if present) or a local
1199  * database lookup */
1200 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1201                                            struct auth_session_info **_session_info)
1202 {
1203         NTSTATUS nt_status;
1204         TALLOC_CTX *mem_ctx;
1205         struct gensec_gssapi_state *gensec_gssapi_state
1206                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1207         struct auth_serversupplied_info *server_info = NULL;
1208         struct auth_session_info *session_info = NULL;
1209         struct PAC_LOGON_INFO *logon_info;
1210         OM_uint32 maj_stat, min_stat;
1211         gss_buffer_desc name_token;
1212         gss_buffer_desc pac;
1213         krb5_keyblock *keyblock;
1214         time_t authtime;
1215         krb5_principal principal;
1216         char *principal_string;
1217         DATA_BLOB pac_blob;
1218
1219         if ((gensec_gssapi_state->gss_oid->length != gss_mech_krb5->length)
1220             || (memcmp(gensec_gssapi_state->gss_oid->elements, gss_mech_krb5->elements,
1221                        gensec_gssapi_state->gss_oid->length) != 0)) {
1222                 DEBUG(1, ("NO session info available for this mech\n"));
1223                 return NT_STATUS_INVALID_PARAMETER;
1224         }
1225
1226         mem_ctx = talloc_named(gensec_gssapi_state, 0, "gensec_gssapi_session_info context");
1227         NT_STATUS_HAVE_NO_MEMORY(mem_ctx);
1228
1229         maj_stat = gss_display_name (&min_stat,
1230                                      gensec_gssapi_state->client_name,
1231                                      &name_token,
1232                                      NULL);
1233         if (GSS_ERROR(maj_stat)) {
1234                 DEBUG(1, ("GSS display_name failed: %s\n",
1235                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1236                 talloc_free(mem_ctx);
1237                 return NT_STATUS_FOOBAR;
1238         }
1239
1240         principal_string = talloc_strndup(mem_ctx,
1241                                           (const char *)name_token.value,
1242                                           name_token.length);
1243
1244         gss_release_buffer(&min_stat, &name_token);
1245
1246         if (!principal_string) {
1247                 talloc_free(mem_ctx);
1248                 return NT_STATUS_NO_MEMORY;
1249         }
1250
1251         maj_stat = gsskrb5_extract_authz_data_from_sec_context(&min_stat,
1252                                                                gensec_gssapi_state->gssapi_context,
1253                                                                KRB5_AUTHDATA_WIN2K_PAC,
1254                                                                &pac);
1255
1256
1257         if (maj_stat == 0) {
1258                 pac_blob = data_blob_talloc(mem_ctx, pac.value, pac.length);
1259                 gss_release_buffer(&min_stat, &pac);
1260
1261         } else {
1262                 pac_blob = data_blob(NULL, 0);
1263         }
1264
1265         /* IF we have the PAC - otherwise we need to get this
1266          * data from elsewere - local ldb, or (TODO) lookup of some
1267          * kind...
1268          */
1269         if (pac_blob.length) {
1270                 krb5_error_code ret;
1271                 union netr_Validation validation;
1272
1273                 maj_stat = gsskrb5_extract_authtime_from_sec_context(&min_stat,
1274                                                                      gensec_gssapi_state->gssapi_context,
1275                                                                      &authtime);
1276
1277                 if (GSS_ERROR(maj_stat)) {
1278                         DEBUG(1, ("gsskrb5_extract_authtime_from_sec_context: %s\n",
1279                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1280                         talloc_free(mem_ctx);
1281                         return NT_STATUS_FOOBAR;
1282                 }
1283
1284                 maj_stat = gsskrb5_extract_service_keyblock(&min_stat,
1285                                                             gensec_gssapi_state->gssapi_context,
1286                                                             &keyblock);
1287
1288                 if (GSS_ERROR(maj_stat)) {
1289                         DEBUG(1, ("gsskrb5_copy_service_keyblock failed: %s\n",
1290                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1291                         talloc_free(mem_ctx);
1292                         return NT_STATUS_FOOBAR;
1293                 }
1294
1295                 ret = krb5_parse_name_flags(gensec_gssapi_state->smb_krb5_context->krb5_context,
1296                                             principal_string,
1297                                             KRB5_PRINCIPAL_PARSE_MUST_REALM,
1298                                             &principal);
1299                 if (ret) {
1300                         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context,
1301                                            keyblock);
1302                         talloc_free(mem_ctx);
1303                         return NT_STATUS_INVALID_PARAMETER;
1304                 }
1305
1306                 /* decode and verify the pac */
1307                 nt_status = kerberos_pac_logon_info(mem_ctx, lp_iconv_convenience(gensec_security->lp_ctx), &logon_info, pac_blob,
1308                                                     gensec_gssapi_state->smb_krb5_context->krb5_context,
1309                                                     NULL, keyblock, principal, authtime, NULL);
1310                 krb5_free_principal(gensec_gssapi_state->smb_krb5_context->krb5_context, principal);
1311                 krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context,
1312                                    keyblock);
1313
1314                 if (!NT_STATUS_IS_OK(nt_status)) {
1315                         talloc_free(mem_ctx);
1316                         return nt_status;
1317                 }
1318                 validation.sam3 = &logon_info->info3;
1319                 nt_status = make_server_info_netlogon_validation(gensec_gssapi_state,
1320                                                                  NULL,
1321                                                                  3, &validation,
1322                                                                  &server_info);
1323                 if (!NT_STATUS_IS_OK(nt_status)) {
1324                         talloc_free(mem_ctx);
1325                         return nt_status;
1326                 }
1327         } else if (!lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec", "require_pac", false)) {
1328                 DEBUG(1, ("Unable to find PAC, resorting to local user lookup: %s\n",
1329                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1330                 nt_status = sam_get_server_info_principal(mem_ctx, gensec_security->event_ctx, gensec_security->lp_ctx, principal_string,
1331                                                           &server_info);
1332
1333                 if (!NT_STATUS_IS_OK(nt_status)) {
1334                         talloc_free(mem_ctx);
1335                         return nt_status;
1336                 }
1337         } else {
1338                 DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access: %s\n",
1339                           principal_string,
1340                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1341                 return NT_STATUS_ACCESS_DENIED;
1342         }
1343
1344         /* references the server_info into the session_info */
1345         nt_status = auth_generate_session_info(mem_ctx, gensec_security->event_ctx, gensec_security->lp_ctx, server_info, &session_info);
1346         if (!NT_STATUS_IS_OK(nt_status)) {
1347                 talloc_free(mem_ctx);
1348                 return nt_status;
1349         }
1350
1351         nt_status = gensec_gssapi_session_key(gensec_security, &session_info->session_key);
1352         if (!NT_STATUS_IS_OK(nt_status)) {
1353                 talloc_free(mem_ctx);
1354                 return nt_status;
1355         }
1356
1357         if (!(gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG)) {
1358                 DEBUG(10, ("gensec_gssapi: NO delegated credentials supplied by client\n"));
1359         } else {
1360                 krb5_error_code ret;
1361                 DEBUG(10, ("gensec_gssapi: delegated credentials supplied by client\n"));
1362                 session_info->credentials = cli_credentials_init(session_info);
1363                 if (!session_info->credentials) {
1364                         talloc_free(mem_ctx);
1365                         return NT_STATUS_NO_MEMORY;
1366                 }
1367
1368                 cli_credentials_set_conf(session_info->credentials, gensec_security->lp_ctx);
1369                 /* Just so we don't segfault trying to get at a username */
1370                 cli_credentials_set_anonymous(session_info->credentials);
1371
1372                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1373                                                            gensec_security->event_ctx,
1374                                                            gensec_security->lp_ctx,
1375                                                            gensec_gssapi_state->delegated_cred_handle,
1376                                                            CRED_SPECIFIED);
1377                 if (ret) {
1378                         talloc_free(mem_ctx);
1379                         return NT_STATUS_NO_MEMORY;
1380                 }
1381
1382                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1383                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1384
1385                 /* It has been taken from this place... */
1386                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1387         }
1388         talloc_steal(gensec_gssapi_state, session_info);
1389         talloc_free(mem_ctx);
1390         *_session_info = session_info;
1391
1392         return NT_STATUS_OK;
1393 }
1394
1395 static const char *gensec_gssapi_krb5_oids[] = {
1396         GENSEC_OID_KERBEROS5_OLD,
1397         GENSEC_OID_KERBEROS5,
1398         NULL
1399 };
1400
1401 static const char *gensec_gssapi_spnego_oids[] = {
1402         GENSEC_OID_SPNEGO,
1403         NULL
1404 };
1405
1406 /* As a server, this could in theory accept any GSSAPI mech */
1407 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1408         .name           = "gssapi_spnego",
1409         .sasl_name      = "GSS-SPNEGO",
1410         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1411         .oid            = gensec_gssapi_spnego_oids,
1412         .client_start   = gensec_gssapi_client_start,
1413         .server_start   = gensec_gssapi_server_start,
1414         .magic          = gensec_gssapi_magic,
1415         .update         = gensec_gssapi_update,
1416         .session_key    = gensec_gssapi_session_key,
1417         .session_info   = gensec_gssapi_session_info,
1418         .sign_packet    = gensec_gssapi_sign_packet,
1419         .check_packet   = gensec_gssapi_check_packet,
1420         .seal_packet    = gensec_gssapi_seal_packet,
1421         .unseal_packet  = gensec_gssapi_unseal_packet,
1422         .wrap           = gensec_gssapi_wrap,
1423         .unwrap         = gensec_gssapi_unwrap,
1424         .have_feature   = gensec_gssapi_have_feature,
1425         .enabled        = false,
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_krb5_security_ops = {
1432         .name           = "gssapi_krb5",
1433         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1434         .oid            = gensec_gssapi_krb5_oids,
1435         .client_start   = gensec_gssapi_client_start,
1436         .server_start   = gensec_gssapi_server_start,
1437         .magic          = gensec_gssapi_magic,
1438         .update         = gensec_gssapi_update,
1439         .session_key    = gensec_gssapi_session_key,
1440         .session_info   = gensec_gssapi_session_info,
1441         .sign_packet    = gensec_gssapi_sign_packet,
1442         .check_packet   = gensec_gssapi_check_packet,
1443         .seal_packet    = gensec_gssapi_seal_packet,
1444         .unseal_packet  = gensec_gssapi_unseal_packet,
1445         .wrap           = gensec_gssapi_wrap,
1446         .unwrap         = gensec_gssapi_unwrap,
1447         .have_feature   = gensec_gssapi_have_feature,
1448         .enabled        = true,
1449         .kerberos       = true,
1450         .priority       = GENSEC_GSSAPI
1451 };
1452
1453 /* As a server, this could in theory accept any GSSAPI mech */
1454 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1455         .name             = "gssapi_krb5_sasl",
1456         .sasl_name        = "GSSAPI",
1457         .client_start     = gensec_gssapi_sasl_client_start,
1458         .server_start     = gensec_gssapi_sasl_server_start,
1459         .update           = gensec_gssapi_update,
1460         .session_key      = gensec_gssapi_session_key,
1461         .session_info     = gensec_gssapi_session_info,
1462         .max_input_size   = gensec_gssapi_max_input_size,
1463         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1464         .wrap             = gensec_gssapi_wrap,
1465         .unwrap           = gensec_gssapi_unwrap,
1466         .have_feature     = gensec_gssapi_have_feature,
1467         .enabled          = true,
1468         .kerberos         = true,
1469         .priority         = GENSEC_GSSAPI
1470 };
1471
1472 _PUBLIC_ NTSTATUS gensec_gssapi_init(void)
1473 {
1474         NTSTATUS ret;
1475
1476         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1477         if (!NT_STATUS_IS_OK(ret)) {
1478                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1479                         gensec_gssapi_spnego_security_ops.name));
1480                 return ret;
1481         }
1482
1483         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1484         if (!NT_STATUS_IS_OK(ret)) {
1485                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1486                         gensec_gssapi_krb5_security_ops.name));
1487                 return ret;
1488         }
1489
1490         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1491         if (!NT_STATUS_IS_OK(ret)) {
1492                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1493                         gensec_gssapi_sasl_krb5_security_ops.name));
1494                 return ret;
1495         }
1496
1497         return ret;
1498 }