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
  38 enum gensec_gssapi_sasl_state
  39 {
  40         STAGE_GSS_NEG,
  41         STAGE_SASL_SSF_NEG,
  42         STAGE_SASL_SSF_ACCEPT,
  43         STAGE_DONE
  44 };
  45
  46 #define NEG_SEAL 0x4
  47 #define NEG_SIGN 0x2
  48 #define NEG_NONE 0x1
  49
  50 struct gensec_gssapi_state {
  51         gss_ctx_id_t gssapi_context;
  52         struct gss_channel_bindings_struct *input_chan_bindings;
  53         gss_name_t server_name;
  54         gss_name_t client_name;
  55         OM_uint32 want_flags, got_flags;
  56         const gss_OID_desc *gss_oid;
  57
  58         DATA_BLOB session_key;
  59         DATA_BLOB pac;
  60
  61         struct smb_krb5_context *smb_krb5_context;
  62         struct gssapi_creds_container *client_cred;
  63         struct gssapi_creds_container *server_cred;
  64
  65         gss_cred_id_t delegated_cred_handle;
  66
  67         BOOL sasl; /* We have two different mechs in this file: One
  68                     * for SASL wrapped GSSAPI and another for normal
  69                     * GSSAPI */
  70         enum gensec_gssapi_sasl_state sasl_state;
  71         uint8_t sasl_protection; /* What was negotiated at the SASL
  72                                   * layer, independent of the GSSAPI
  73                                   * layer... */
  74
  75         size_t max_wrap_buf_size;
  76         int gss_exchange_count;
  77 };
  78
  79 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security);
  80 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security);
  81
  82 static char *gssapi_error_string(TALLOC_CTX *mem_ctx,
  83                                  OM_uint32 maj_stat, OM_uint32 min_stat,
  84                                  const gss_OID_desc *mech)
  85 {
  86         OM_uint32 disp_min_stat, disp_maj_stat;
  87         gss_buffer_desc maj_error_message;
  88         gss_buffer_desc min_error_message;
  89         char *maj_error_string, *min_error_string;
  90         OM_uint32 msg_ctx = 0;
  91
  92         char *ret;
  93
  94         maj_error_message.value = NULL;
  95         min_error_message.value = NULL;
  96         maj_error_message.length = 0;
  97         min_error_message.length = 0;
  98
  99         disp_maj_stat = gss_display_status(&disp_min_stat, maj_stat, GSS_C_GSS_CODE,
 100                            mech, &msg_ctx, &maj_error_message);
 101         disp_maj_stat = gss_display_status(&disp_min_stat, min_stat, GSS_C_MECH_CODE,
 102                            mech, &msg_ctx, &min_error_message);
 103
 104         maj_error_string = talloc_strndup(mem_ctx, (char *)maj_error_message.value, maj_error_message.length);
 105
 106         min_error_string = talloc_strndup(mem_ctx, (char *)min_error_message.value, min_error_message.length);
 107
 108         ret = talloc_asprintf(mem_ctx, "%s: %s", maj_error_string, min_error_string);
 109
 110         talloc_free(maj_error_string);
 111         talloc_free(min_error_string);
 112
 113         gss_release_buffer(&disp_min_stat, &maj_error_message);
 114         gss_release_buffer(&disp_min_stat, &min_error_message);
 115
 116         return ret;
 117 }
 118
 119
 120 static int gensec_gssapi_destructor(struct gensec_gssapi_state *gensec_gssapi_state)
 121 {
 122         OM_uint32 maj_stat, min_stat;
 123
 124         if (gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
 125                 maj_stat = gss_release_cred(&min_stat,
 126                                             &gensec_gssapi_state->delegated_cred_handle);
 127         }
 128
 129         if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
 130                 maj_stat = gss_delete_sec_context (&min_stat,
 131                                                    &gensec_gssapi_state->gssapi_context,
 132                                                    GSS_C_NO_BUFFER);
 133         }
 134
 135         if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
 136                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->server_name);
 137         }
 138         if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
 139                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->client_name);
 140         }
 141         return 0;
 142 }
 143
 144 static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 145 {
 146         struct gensec_gssapi_state *gensec_gssapi_state;
 147         krb5_error_code ret;
 148         struct gsskrb5_send_to_kdc send_to_kdc;
 149
 150         gensec_gssapi_state = talloc(gensec_security, struct gensec_gssapi_state);
 151         if (!gensec_gssapi_state) {
 152                 return NT_STATUS_NO_MEMORY;
 153         }
 154
 155         gensec_gssapi_state->gss_exchange_count = 0;
 156         gensec_gssapi_state->max_wrap_buf_size
 157                 = lp_parm_int(-1, "gensec_gssapi", "max wrap buf size", 65536);
 158
 159         gensec_gssapi_state->sasl = False;
 160         gensec_gssapi_state->sasl_state = STAGE_GSS_NEG;
 161
 162         gensec_security->private_data = gensec_gssapi_state;
 163
 164         gensec_gssapi_state->gssapi_context = GSS_C_NO_CONTEXT;
 165         gensec_gssapi_state->server_name = GSS_C_NO_NAME;
 166         gensec_gssapi_state->client_name = GSS_C_NO_NAME;
 167
 168         /* TODO: Fill in channel bindings */
 169         gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
 170
 171         gensec_gssapi_state->want_flags = 0;
 172         if (lp_parm_bool(-1, "gensec_gssapi", "mutual", True)) {
 173                 gensec_gssapi_state->want_flags |= GSS_C_MUTUAL_FLAG;
 174         }
 175         if (lp_parm_bool(-1, "gensec_gssapi", "delegation", True)) {
 176                 gensec_gssapi_state->want_flags |= GSS_C_DELEG_FLAG;
 177         }
 178         if (lp_parm_bool(-1, "gensec_gssapi", "replay", True)) {
 179                 gensec_gssapi_state->want_flags |= GSS_C_REPLAY_FLAG;
 180         }
 181         if (lp_parm_bool(-1, "gensec_gssapi", "sequence", True)) {
 182                 gensec_gssapi_state->want_flags |= GSS_C_SEQUENCE_FLAG;
 183         }
 184
 185         gensec_gssapi_state->got_flags = 0;
 186
 187         gensec_gssapi_state->session_key = data_blob(NULL, 0);
 188         gensec_gssapi_state->pac = data_blob(NULL, 0);
 189
 190         gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 191
 192         talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 193
 194         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 195                 gensec_gssapi_state->want_flags |= GSS_C_INTEG_FLAG;
 196         }
 197         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 198                 gensec_gssapi_state->want_flags |= GSS_C_CONF_FLAG;
 199         }
 200         if (gensec_security->want_features & GENSEC_FEATURE_DCE_STYLE) {
 201                 gensec_gssapi_state->want_flags |= GSS_C_DCE_STYLE;
 202         }
 203
 204         gensec_gssapi_state->gss_oid = GSS_C_NULL_OID;
 205
 206         send_to_kdc.func = smb_krb5_send_and_recv_func;
 207         send_to_kdc.ptr = gensec_security->event_ctx;
 208
 209         ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
 210         if (ret) {
 211                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 212                 talloc_free(gensec_gssapi_state);
 213                 return NT_STATUS_INTERNAL_ERROR;
 214         }
 215         if (lp_realm() && *lp_realm()) {
 216                 char *upper_realm = strupper_talloc(gensec_gssapi_state, lp_realm());
 217                 if (!upper_realm) {
 218                         DEBUG(1,("gensec_krb5_start: could not uppercase realm: %s\n", lp_realm()));
 219                         talloc_free(gensec_gssapi_state);
 220                         return NT_STATUS_NO_MEMORY;
 221                 }
 222                 ret = gsskrb5_set_default_realm(upper_realm);
 223                 talloc_free(upper_realm);
 224                 if (ret) {
 225                         DEBUG(1,("gensec_krb5_start: gsskrb5_set_default_realm failed\n"));
 226                         talloc_free(gensec_gssapi_state);
 227                         return NT_STATUS_INTERNAL_ERROR;
 228                 }
 229         }
 230
 231         /* don't do DNS lookups of any kind, it might/will fail for a netbios name */
 232         ret = gsskrb5_set_dns_canonicalize(lp_parm_bool(-1, "krb5", "set_dns_canonicalize", false));
 233         if (ret) {
 234                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_dns_canonicalize failed\n"));
 235                 talloc_free(gensec_gssapi_state);
 236                 return NT_STATUS_INTERNAL_ERROR;
 237         }
 238
 239         ret = smb_krb5_init_context(gensec_gssapi_state,
 240                                     gensec_security->event_ctx,
 241                                     &gensec_gssapi_state->smb_krb5_context);
 242         if (ret) {
 243                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n",
 244                          error_message(ret)));
 245                 talloc_free(gensec_gssapi_state);
 246                 return NT_STATUS_INTERNAL_ERROR;
 247         }
 248         return NT_STATUS_OK;
 249 }
 250
 251 static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
 252 {
 253         NTSTATUS nt_status;
 254         int ret;
 255         struct gensec_gssapi_state *gensec_gssapi_state;
 256         struct cli_credentials *machine_account;
 257         struct gssapi_creds_container *gcc;
 258
 259         nt_status = gensec_gssapi_start(gensec_security);
 260         if (!NT_STATUS_IS_OK(nt_status)) {
 261                 return nt_status;
 262         }
 263
 264         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 265
 266         machine_account = gensec_get_credentials(gensec_security);
 267
 268         if (!machine_account) {
 269                 DEBUG(3, ("No machine account credentials specified\n"));
 270                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 271         } else {
 272                 ret = cli_credentials_get_server_gss_creds(machine_account, &gcc);
 273                 if (ret) {
 274                         DEBUG(1, ("Aquiring acceptor credentials failed: %s\n",
 275                                   error_message(ret)));
 276                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 277                 }
 278         }
 279
 280         gensec_gssapi_state->server_cred = gcc;
 281         return NT_STATUS_OK;
 282
 283 }
 284
 285 static NTSTATUS gensec_gssapi_sasl_server_start(struct gensec_security *gensec_security)
 286 {
 287         NTSTATUS nt_status;
 288         struct gensec_gssapi_state *gensec_gssapi_state;
 289         nt_status = gensec_gssapi_server_start(gensec_security);
 290
 291         if (NT_STATUS_IS_OK(nt_status)) {
 292                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 293                 gensec_gssapi_state->sasl = True;
 294         }
 295         return nt_status;
 296 }
 297
 298 static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
 299 {
 300         struct gensec_gssapi_state *gensec_gssapi_state;
 301         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 302         krb5_error_code ret;
 303         NTSTATUS nt_status;
 304         gss_buffer_desc name_token;
 305         gss_OID name_type;
 306         OM_uint32 maj_stat, min_stat;
 307         const char *hostname = gensec_get_target_hostname(gensec_security);
 308         const char *principal;
 309         struct gssapi_creds_container *gcc;
 310
 311         if (!hostname) {
 312                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 313                 return NT_STATUS_INVALID_PARAMETER;
 314         }
 315         if (is_ipaddress(hostname)) {
 316                 DEBUG(2, ("Cannot do GSSAPI to an IP address\n"));
 317                 return NT_STATUS_INVALID_PARAMETER;
 318         }
 319         if (strcmp(hostname, "localhost") == 0) {
 320                 DEBUG(2, ("GSSAPI to 'localhost' does not make sense\n"));
 321                 return NT_STATUS_INVALID_PARAMETER;
 322         }
 323
 324         nt_status = gensec_gssapi_start(gensec_security);
 325         if (!NT_STATUS_IS_OK(nt_status)) {
 326                 return nt_status;
 327         }
 328
 329         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 330
 331         gensec_gssapi_state->gss_oid = gss_mech_krb5;
 332
 333         principal = gensec_get_target_principal(gensec_security);
 334         if (principal && lp_client_use_spnego_principal()) {
 335                 name_type = GSS_C_NULL_OID;
 336         } else {
 337                 principal = talloc_asprintf(gensec_gssapi_state, "%s@%s",
 338                                             gensec_get_target_service(gensec_security),
 339                                             hostname);
 340
 341                 name_type = GSS_C_NT_HOSTBASED_SERVICE;
 342         }
 343         name_token.value  = discard_const_p(uint8_t, principal);
 344         name_token.length = strlen(principal);
 345
 346
 347         maj_stat = gss_import_name (&min_stat,
 348                                     &name_token,
 349                                     name_type,
 350                                     &gensec_gssapi_state->server_name);
 351         if (maj_stat) {
 352                 DEBUG(2, ("GSS Import name of %s failed: %s\n",
 353                           (char *)name_token.value,
 354                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 355                 return NT_STATUS_INVALID_PARAMETER;
 356         }
 357
 358         ret = cli_credentials_get_client_gss_creds(creds, &gcc);
 359         switch (ret) {
 360         case 0:
 361                 break;
 362         case KRB5KDC_ERR_PREAUTH_FAILED:
 363                 return NT_STATUS_LOGON_FAILURE;
 364         case KRB5_KDC_UNREACH:
 365                 DEBUG(3, ("Cannot reach a KDC we require to contact %s\n", principal));
 366                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 367         default:
 368                 DEBUG(1, ("Aquiring initiator credentails failed\n"));
 369                 return NT_STATUS_UNSUCCESSFUL;
 370         }
 371
 372         gensec_gssapi_state->client_cred = gcc;
 373         if (!talloc_reference(gensec_gssapi_state, gcc)) {
 374                 return NT_STATUS_NO_MEMORY;
 375         }
 376
 377         return NT_STATUS_OK;
 378 }
 379
 380 static NTSTATUS gensec_gssapi_sasl_client_start(struct gensec_security *gensec_security)
 381 {
 382         NTSTATUS nt_status;
 383         struct gensec_gssapi_state *gensec_gssapi_state;
 384         nt_status = gensec_gssapi_client_start(gensec_security);
 385
 386         if (NT_STATUS_IS_OK(nt_status)) {
 387                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 388                 gensec_gssapi_state->sasl = True;
 389         }
 390         return nt_status;
 391 }
 392
 393
 394 /**
 395  * Check if the packet is one for this mechansim
 396  *
 397  * @param gensec_security GENSEC state
 398  * @param in The request, as a DATA_BLOB
 399  * @return Error, INVALID_PARAMETER if it's not a packet for us
 400  *                or NT_STATUS_OK if the packet is ok.
 401  */
 402
 403 static NTSTATUS gensec_gssapi_magic(struct gensec_security *gensec_security,
 404                                     const DATA_BLOB *in)
 405 {
 406         if (gensec_gssapi_check_oid(in, GENSEC_OID_KERBEROS5)) {
 407                 return NT_STATUS_OK;
 408         } else {
 409                 return NT_STATUS_INVALID_PARAMETER;
 410         }
 411 }
 412
 413
 414 /**
 415  * Next state function for the GSSAPI GENSEC mechanism
 416  *
 417  * @param gensec_gssapi_state GSSAPI State
 418  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 419  * @param in The request, as a DATA_BLOB
 420  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 421  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 422  *                or NT_STATUS_OK if the user is authenticated.
 423  */
 424
 425 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 426                                    TALLOC_CTX *out_mem_ctx,
 427                                    const DATA_BLOB in, DATA_BLOB *out)
 428 {
 429         struct gensec_gssapi_state *gensec_gssapi_state
 430                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 431         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 432         OM_uint32 maj_stat, min_stat;
 433         OM_uint32 min_stat2;
 434         gss_buffer_desc input_token, output_token;
 435         gss_OID gss_oid_p = NULL;
 436         input_token.length = in.length;
 437         input_token.value = in.data;
 438
 439         switch (gensec_gssapi_state->sasl_state) {
 440         case STAGE_GSS_NEG:
 441         {
 442                 switch (gensec_security->gensec_role) {
 443                 case GENSEC_CLIENT:
 444                 {
 445                         maj_stat = gss_init_sec_context(&min_stat,
 446                                                         gensec_gssapi_state->client_cred->creds,
 447                                                         &gensec_gssapi_state->gssapi_context,
 448                                                         gensec_gssapi_state->server_name,
 449                                                         discard_const_p(gss_OID_desc, gensec_gssapi_state->gss_oid),
 450                                                         gensec_gssapi_state->want_flags,
 451                                                         0,
 452                                                         gensec_gssapi_state->input_chan_bindings,
 453                                                         &input_token,
 454                                                         &gss_oid_p,
 455                                                         &output_token,
 456                                                         &gensec_gssapi_state->got_flags, /* ret flags */
 457                                                         NULL);
 458                         if (gss_oid_p) {
 459                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 460                         }
 461                         break;
 462                 }
 463                 case GENSEC_SERVER:
 464                 {
 465                         maj_stat = gss_accept_sec_context(&min_stat,
 466                                                           &gensec_gssapi_state->gssapi_context,
 467                                                           gensec_gssapi_state->server_cred->creds,
 468                                                           &input_token,
 469                                                           gensec_gssapi_state->input_chan_bindings,
 470                                                           &gensec_gssapi_state->client_name,
 471                                                           &gss_oid_p,
 472                                                           &output_token,
 473                                                           &gensec_gssapi_state->got_flags,
 474                                                           NULL,
 475                                                           &gensec_gssapi_state->delegated_cred_handle);
 476                         if (gss_oid_p) {
 477                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 478                         }
 479                         break;
 480                 }
 481                 default:
 482                         return NT_STATUS_INVALID_PARAMETER;
 483
 484                 }
 485
 486                 gensec_gssapi_state->gss_exchange_count++;
 487
 488                 if (maj_stat == GSS_S_COMPLETE) {
 489                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 490                         gss_release_buffer(&min_stat2, &output_token);
 491
 492                         if (gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG) {
 493                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 494                         } else {
 495                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 496                         }
 497
 498                         /* We may have been invoked as SASL, so there
 499                          * is more work to do */
 500                         if (gensec_gssapi_state->sasl) {
 501                                 /* Due to a very subtle interaction
 502                                  * with SASL and the LDAP libs, we
 503                                  * must ensure the data pointer is
 504                                  * != NULL, but the length is 0.
 505                                  *
 506                                  * This ensures we send a 'zero
 507                                  * length' (rather than NULL) response
 508                                  */
 509
 510                                 if (!out->data) {
 511                                         out->data = (uint8_t *)talloc_strdup(out_mem_ctx, "\0");
 512                                 }
 513
 514                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 515                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 516                         } else {
 517                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 518
 519                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 520                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly sealed\n"));
 521                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 522                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly signed\n"));
 523                                 } else {
 524                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 525                                 }
 526
 527                                 return NT_STATUS_OK;
 528                         }
 529                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 530                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 531                         gss_release_buffer(&min_stat2, &output_token);
 532
 533                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 534                 } else if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
 535                         switch (min_stat) {
 536                         case KRB5_KDC_UNREACH:
 537                                 DEBUG(3, ("Cannot reach a KDC we require: %s\n",
 538                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 539                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 540                         case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 541                                 DEBUG(3, ("Server is not registered with our KDC: %s\n",
 542                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 543                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 544                         case KRB5KRB_AP_ERR_MSG_TYPE:
 545                                 /* garbage input, possibly from the auto-mech detection */
 546                                 return NT_STATUS_INVALID_PARAMETER;
 547                         default:
 548                                 DEBUG(1, ("GSS Update(krb5)(%d) Update failed: %s\n",
 549                                           gensec_gssapi_state->gss_exchange_count,
 550                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 551                                 return nt_status;
 552                         }
 553                 } else {
 554                         DEBUG(1, ("GSS Update(%d) failed: %s\n",
 555                                   gensec_gssapi_state->gss_exchange_count,
 556                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 557                         return nt_status;
 558                 }
 559                 break;
 560         }
 561
 562         /* These last two stages are only done if we were invoked as SASL */
 563         case STAGE_SASL_SSF_NEG:
 564         {
 565                 switch (gensec_security->gensec_role) {
 566                 case GENSEC_CLIENT:
 567                 {
 568                         uint8_t maxlength_proposed[4];
 569                         uint8_t maxlength_accepted[4];
 570                         uint8_t security_supported;
 571                         int conf_state;
 572                         gss_qop_t qop_state;
 573                         input_token.length = in.length;
 574                         input_token.value = in.data;
 575
 576                         /* As a client, we have just send a
 577                          * zero-length blob to the server (after the
 578                          * normal GSSAPI exchange), and it has replied
 579                          * with it's SASL negotiation */
 580
 581                         maj_stat = gss_unwrap(&min_stat,
 582                                               gensec_gssapi_state->gssapi_context,
 583                                               &input_token,
 584                                               &output_token,
 585                                               &conf_state,
 586                                               &qop_state);
 587                         if (GSS_ERROR(maj_stat)) {
 588                                 DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 589                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 590                                 return NT_STATUS_ACCESS_DENIED;
 591                         }
 592
 593                         if (output_token.length < 4) {
 594                                 return NT_STATUS_INVALID_PARAMETER;
 595                         }
 596
 597                         memcpy(maxlength_proposed, output_token.value, 4);
 598                         gss_release_buffer(&min_stat, &output_token);
 599
 600                         /* first byte is the proposed security */
 601                         security_supported = maxlength_proposed[0];
 602                         maxlength_proposed[0] = '\0';
 603
 604                         /* Rest is the proposed max wrap length */
 605                         gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_proposed, 0),
 606                                                                      gensec_gssapi_state->max_wrap_buf_size);
 607                         gensec_gssapi_state->sasl_protection = 0;
 608                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 609                                 if (security_supported & NEG_SEAL) {
 610                                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 611                                 }
 612                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 613                                 if (security_supported & NEG_SIGN) {
 614                                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 615                                 }
 616                         } else if (security_supported & NEG_NONE) {
 617                                 gensec_gssapi_state->sasl_protection |= NEG_NONE;
 618                         } else {
 619                                 DEBUG(1, ("Remote server does not support unprotected connections"));
 620                                 return NT_STATUS_ACCESS_DENIED;
 621                         }
 622
 623                         /* Send back the negotiated max length */
 624
 625                         RSIVAL(maxlength_accepted, 0, gensec_gssapi_state->max_wrap_buf_size);
 626
 627                         maxlength_accepted[0] = gensec_gssapi_state->sasl_protection;
 628
 629                         input_token.value = maxlength_accepted;
 630                         input_token.length = sizeof(maxlength_accepted);
 631
 632                         maj_stat = gss_wrap(&min_stat,
 633                                             gensec_gssapi_state->gssapi_context,
 634                                             False,
 635                                             GSS_C_QOP_DEFAULT,
 636                                             &input_token,
 637                                             &conf_state,
 638                                             &output_token);
 639                         if (GSS_ERROR(maj_stat)) {
 640                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 641                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 642                                 return NT_STATUS_ACCESS_DENIED;
 643                         }
 644
 645                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 646                         gss_release_buffer(&min_stat, &output_token);
 647
 648                         /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 649                         gensec_gssapi_state->sasl_state = STAGE_DONE;
 650
 651                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 652                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly sealed\n"));
 653                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 654                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly signed\n"));
 655                         } else {
 656                                 DEBUG(3, ("SASL/GSSAPI Connection to server will have no cryptographicly protection\n"));
 657                         }
 658
 659                         return NT_STATUS_OK;
 660                 }
 661                 case GENSEC_SERVER:
 662                 {
 663                         uint8_t maxlength_proposed[4];
 664                         uint8_t security_supported = 0x0;
 665                         int conf_state;
 666
 667                         /* As a server, we have just been sent a zero-length blob (note this, but it isn't fatal) */
 668                         if (in.length != 0) {
 669                                 DEBUG(1, ("SASL/GSSAPI: client sent non-zero length starting SASL negotiation!\n"));
 670                         }
 671
 672                         /* Give the client some idea what we will support */
 673
 674                         RSIVAL(maxlength_proposed, 0, gensec_gssapi_state->max_wrap_buf_size);
 675                         /* first byte is the proposed security */
 676                         maxlength_proposed[0] = '\0';
 677
 678                         gensec_gssapi_state->sasl_protection = 0;
 679                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 680                                 security_supported |= NEG_SEAL;
 681                         }
 682                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 683                                 security_supported |= NEG_SIGN;
 684                         }
 685                         if (security_supported == 0) {
 686                                 /* If we don't support anything, this must be 0 */
 687                                 RSIVAL(maxlength_proposed, 0, 0x0);
 688                         }
 689
 690                         /* TODO:  We may not wish to support this */
 691                         security_supported |= NEG_NONE;
 692                         maxlength_proposed[0] = security_supported;
 693
 694                         input_token.value = maxlength_proposed;
 695                         input_token.length = sizeof(maxlength_proposed);
 696
 697                         maj_stat = gss_wrap(&min_stat,
 698                                             gensec_gssapi_state->gssapi_context,
 699                                             False,
 700                                             GSS_C_QOP_DEFAULT,
 701                                             &input_token,
 702                                             &conf_state,
 703                                             &output_token);
 704                         if (GSS_ERROR(maj_stat)) {
 705                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 706                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 707                                 return NT_STATUS_ACCESS_DENIED;
 708                         }
 709
 710                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 711                         gss_release_buffer(&min_stat, &output_token);
 712
 713                         gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_ACCEPT;
 714                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 715                 }
 716                 default:
 717                         return NT_STATUS_INVALID_PARAMETER;
 718
 719                 }
 720         }
 721         /* This is s server-only stage */
 722         case STAGE_SASL_SSF_ACCEPT:
 723         {
 724                 uint8_t maxlength_accepted[4];
 725                 uint8_t security_accepted;
 726                 int conf_state;
 727                 gss_qop_t qop_state;
 728                 input_token.length = in.length;
 729                 input_token.value = in.data;
 730
 731                 maj_stat = gss_unwrap(&min_stat,
 732                                       gensec_gssapi_state->gssapi_context,
 733                                       &input_token,
 734                                       &output_token,
 735                                       &conf_state,
 736                                       &qop_state);
 737                 if (GSS_ERROR(maj_stat)) {
 738                         DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 739                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 740                         return NT_STATUS_ACCESS_DENIED;
 741                 }
 742
 743                 if (output_token.length < 4) {
 744                         return NT_STATUS_INVALID_PARAMETER;
 745                 }
 746
 747                 memcpy(maxlength_accepted, output_token.value, 4);
 748                 gss_release_buffer(&min_stat, &output_token);
 749
 750                 /* first byte is the proposed security */
 751                 security_accepted = maxlength_accepted[0];
 752                 maxlength_accepted[0] = '\0';
 753
 754                 /* Rest is the proposed max wrap length */
 755                 gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_accepted, 0),
 756                                                              gensec_gssapi_state->max_wrap_buf_size);
 757
 758                 gensec_gssapi_state->sasl_protection = 0;
 759                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 760                         if (security_accepted & NEG_SEAL) {
 761                                 gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 762                         }
 763                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 764                         if (security_accepted & NEG_SIGN) {
 765                                 gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 766                         }
 767                 } else if (security_accepted & NEG_NONE) {
 768                         gensec_gssapi_state->sasl_protection |= NEG_NONE;
 769                 } else {
 770                         DEBUG(1, ("Remote client does not support unprotected connections, but we failed to negotiate anything better"));
 771                         return NT_STATUS_ACCESS_DENIED;
 772                 }
 773
 774                 /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 775                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 776                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 777                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly sealed\n"));
 778                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 779                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly signed\n"));
 780                 } else {
 781                         DEBUG(5, ("SASL/GSSAPI Connection from client will have no cryptographic protection\n"));
 782                 }
 783
 784                 *out = data_blob(NULL, 0);
 785                 return NT_STATUS_OK;
 786         }
 787         default:
 788                 return NT_STATUS_INVALID_PARAMETER;
 789         }
 790 }
 791
 792 static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security,
 793                                    TALLOC_CTX *mem_ctx,
 794                                    const DATA_BLOB *in,
 795                                    DATA_BLOB *out)
 796 {
 797         struct gensec_gssapi_state *gensec_gssapi_state
 798                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 799         OM_uint32 maj_stat, min_stat;
 800         gss_buffer_desc input_token, output_token;
 801         int conf_state;
 802         input_token.length = in->length;
 803         input_token.value = in->data;
 804
 805         maj_stat = gss_wrap(&min_stat,
 806                             gensec_gssapi_state->gssapi_context,
 807                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 808                             GSS_C_QOP_DEFAULT,
 809                             &input_token,
 810                             &conf_state,
 811                             &output_token);
 812         if (GSS_ERROR(maj_stat)) {
 813                 DEBUG(1, ("gensec_gssapi_wrap: GSS Wrap failed: %s\n",
 814                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 815                 return NT_STATUS_ACCESS_DENIED;
 816         }
 817
 818         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 819         gss_release_buffer(&min_stat, &output_token);
 820
 821         if (gensec_gssapi_state->sasl) {
 822                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 823                 if (max_wrapped_size < out->length) {
 824                         DEBUG(1, ("gensec_gssapi_wrap: when wrapped, INPUT data (%u) is grew to be larger than SASL negotiated maximum output size (%u > %u)\n",
 825                                   (unsigned)in->length,
 826                                   (unsigned)out->length,
 827                                   (unsigned int)max_wrapped_size));
 828                         return NT_STATUS_INVALID_PARAMETER;
 829                 }
 830         }
 831
 832         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 833             && !conf_state) {
 834                 return NT_STATUS_ACCESS_DENIED;
 835         }
 836         return NT_STATUS_OK;
 837 }
 838
 839 static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security,
 840                                      TALLOC_CTX *mem_ctx,
 841                                      const DATA_BLOB *in,
 842                                      DATA_BLOB *out)
 843 {
 844         struct gensec_gssapi_state *gensec_gssapi_state
 845                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 846         OM_uint32 maj_stat, min_stat;
 847         gss_buffer_desc input_token, output_token;
 848         int conf_state;
 849         gss_qop_t qop_state;
 850         input_token.length = in->length;
 851         input_token.value = in->data;
 852
 853         if (gensec_gssapi_state->sasl) {
 854                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 855                 if (max_wrapped_size < in->length) {
 856                         DEBUG(1, ("gensec_gssapi_unwrap: WRAPPED data is larger than SASL negotiated maximum size\n"));
 857                         return NT_STATUS_INVALID_PARAMETER;
 858                 }
 859         }
 860
 861         maj_stat = gss_unwrap(&min_stat,
 862                               gensec_gssapi_state->gssapi_context,
 863                               &input_token,
 864                               &output_token,
 865                               &conf_state,
 866                               &qop_state);
 867         if (GSS_ERROR(maj_stat)) {
 868                 DEBUG(1, ("gensec_gssapi_unwrap: GSS UnWrap failed: %s\n",
 869                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 870                 return NT_STATUS_ACCESS_DENIED;
 871         }
 872
 873         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 874         gss_release_buffer(&min_stat, &output_token);
 875
 876         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 877             && !conf_state) {
 878                 return NT_STATUS_ACCESS_DENIED;
 879         }
 880         return NT_STATUS_OK;
 881 }
 882
 883 /* Find out the maximum input size negotiated on this connection */
 884
 885 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security)
 886 {
 887         struct gensec_gssapi_state *gensec_gssapi_state
 888                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 889         OM_uint32 maj_stat, min_stat;
 890         OM_uint32 max_input_size;
 891
 892         maj_stat = gss_wrap_size_limit(&min_stat,
 893                                        gensec_gssapi_state->gssapi_context,
 894                                        gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 895                                        GSS_C_QOP_DEFAULT,
 896                                        gensec_gssapi_state->max_wrap_buf_size,
 897                                        &max_input_size);
 898         if (GSS_ERROR(maj_stat)) {
 899                 TALLOC_CTX *mem_ctx = talloc_new(NULL);
 900                 DEBUG(1, ("gensec_gssapi_max_input_size: determinaing signature size with gss_wrap_size_limit failed: %s\n",
 901                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 902                 talloc_free(mem_ctx);
 903                 return 0;
 904         }
 905
 906         return max_input_size;
 907 }
 908
 909 /* Find out the maximum output size negotiated on this connection */
 910 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security)
 911 {
 912         struct gensec_gssapi_state *gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);;
 913         return gensec_gssapi_state->max_wrap_buf_size;
 914 }
 915
 916 static NTSTATUS gensec_gssapi_seal_packet(struct gensec_security *gensec_security,
 917                                           TALLOC_CTX *mem_ctx,
 918                                           uint8_t *data, size_t length,
 919                                           const uint8_t *whole_pdu, size_t pdu_length,
 920                                           DATA_BLOB *sig)
 921 {
 922         struct gensec_gssapi_state *gensec_gssapi_state
 923                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 924         OM_uint32 maj_stat, min_stat;
 925         gss_buffer_desc input_token, output_token;
 926         int conf_state;
 927         ssize_t sig_length;
 928
 929         input_token.length = length;
 930         input_token.value = data;
 931
 932         maj_stat = gss_wrap(&min_stat,
 933                             gensec_gssapi_state->gssapi_context,
 934                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 935                             GSS_C_QOP_DEFAULT,
 936                             &input_token,
 937                             &conf_state,
 938                             &output_token);
 939         if (GSS_ERROR(maj_stat)) {
 940                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap failed: %s\n",
 941                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 942                 return NT_STATUS_ACCESS_DENIED;
 943         }
 944
 945         if (output_token.length < input_token.length) {
 946                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
 947                           (long)output_token.length, (long)length));
 948                 return NT_STATUS_INTERNAL_ERROR;
 949         }
 950         sig_length = output_token.length - input_token.length;
 951
 952         memcpy(data, ((uint8_t *)output_token.value) + sig_length, length);
 953         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
 954
 955         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
 956         dump_data_pw("gensec_gssapi_seal_packet: clear\n", data, length);
 957         dump_data_pw("gensec_gssapi_seal_packet: sealed\n", ((uint8_t *)output_token.value) + sig_length, output_token.length - sig_length);
 958
 959         gss_release_buffer(&min_stat, &output_token);
 960
 961         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 962             && !conf_state) {
 963                 return NT_STATUS_ACCESS_DENIED;
 964         }
 965         return NT_STATUS_OK;
 966 }
 967
 968 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
 969                                             TALLOC_CTX *mem_ctx,
 970                                             uint8_t *data, size_t length,
 971                                             const uint8_t *whole_pdu, size_t pdu_length,
 972                                             const DATA_BLOB *sig)
 973 {
 974         struct gensec_gssapi_state *gensec_gssapi_state
 975                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 976         OM_uint32 maj_stat, min_stat;
 977         gss_buffer_desc input_token, output_token;
 978         int conf_state;
 979         gss_qop_t qop_state;
 980         DATA_BLOB in;
 981
 982         dump_data_pw("gensec_gssapi_unseal_packet: sig\n", sig->data, sig->length);
 983
 984         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
 985
 986         memcpy(in.data, sig->data, sig->length);
 987         memcpy(in.data + sig->length, data, length);
 988
 989         input_token.length = in.length;
 990         input_token.value = in.data;
 991
 992         maj_stat = gss_unwrap(&min_stat,
 993                               gensec_gssapi_state->gssapi_context,
 994                               &input_token,
 995                               &output_token,
 996                               &conf_state,
 997                               &qop_state);
 998         if (GSS_ERROR(maj_stat)) {
 999                 DEBUG(1, ("gensec_gssapi_unseal_packet: GSS UnWrap failed: %s\n",
1000                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1001                 return NT_STATUS_ACCESS_DENIED;
1002         }
1003
1004         if (output_token.length != length) {
1005                 return NT_STATUS_INTERNAL_ERROR;
1006         }
1007
1008         memcpy(data, output_token.value, length);
1009
1010         gss_release_buffer(&min_stat, &output_token);
1011
1012         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1013             && !conf_state) {
1014                 return NT_STATUS_ACCESS_DENIED;
1015         }
1016         return NT_STATUS_OK;
1017 }
1018
1019 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1020                                           TALLOC_CTX *mem_ctx,
1021                                           const uint8_t *data, size_t length,
1022                                           const uint8_t *whole_pdu, size_t pdu_length,
1023                                           DATA_BLOB *sig)
1024 {
1025         struct gensec_gssapi_state *gensec_gssapi_state
1026                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1027         OM_uint32 maj_stat, min_stat;
1028         gss_buffer_desc input_token, output_token;
1029         int conf_state;
1030         ssize_t sig_length = 0;
1031
1032         input_token.length = length;
1033         input_token.value = discard_const_p(uint8_t *, data);
1034
1035         maj_stat = gss_wrap(&min_stat,
1036                             gensec_gssapi_state->gssapi_context,
1037                             0,
1038                             GSS_C_QOP_DEFAULT,
1039                             &input_token,
1040                             &conf_state,
1041                             &output_token);
1042         if (GSS_ERROR(maj_stat)) {
1043                 DEBUG(1, ("GSS Wrap failed: %s\n",
1044                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1045                 return NT_STATUS_ACCESS_DENIED;
1046         }
1047
1048         if (output_token.length < input_token.length) {
1049                 DEBUG(1, ("gensec_gssapi_sign_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
1050                           (long)output_token.length, (long)length));
1051                 return NT_STATUS_INTERNAL_ERROR;
1052         }
1053
1054         /* Caller must pad to right boundary */
1055         sig_length = output_token.length - input_token.length;
1056
1057         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
1058
1059         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1060
1061         gss_release_buffer(&min_stat, &output_token);
1062
1063         return NT_STATUS_OK;
1064 }
1065
1066 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1067                                            TALLOC_CTX *mem_ctx,
1068                                            const uint8_t *data, size_t length,
1069                                            const uint8_t *whole_pdu, size_t pdu_length,
1070                                            const DATA_BLOB *sig)
1071 {
1072         struct gensec_gssapi_state *gensec_gssapi_state
1073                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1074         OM_uint32 maj_stat, min_stat;
1075         gss_buffer_desc input_token, output_token;
1076         int conf_state;
1077         gss_qop_t qop_state;
1078         DATA_BLOB in;
1079
1080         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1081
1082         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
1083
1084         memcpy(in.data, sig->data, sig->length);
1085         memcpy(in.data + sig->length, data, length);
1086
1087         input_token.length = in.length;
1088         input_token.value = in.data;
1089
1090         maj_stat = gss_unwrap(&min_stat,
1091                               gensec_gssapi_state->gssapi_context,
1092                               &input_token,
1093                               &output_token,
1094                               &conf_state,
1095                               &qop_state);
1096         if (GSS_ERROR(maj_stat)) {
1097                 DEBUG(1, ("GSS UnWrap failed: %s\n",
1098                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1099                 return NT_STATUS_ACCESS_DENIED;
1100         }
1101
1102         if (output_token.length != length) {
1103                 return NT_STATUS_INTERNAL_ERROR;
1104         }
1105
1106         gss_release_buffer(&min_stat, &output_token);
1107
1108         return NT_STATUS_OK;
1109 }
1110
1111 /* Try to figure out what features we actually got on the connection */
1112 static BOOL gensec_gssapi_have_feature(struct gensec_security *gensec_security,
1113                                        uint32_t feature)
1114 {
1115         struct gensec_gssapi_state *gensec_gssapi_state
1116                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1117         if (feature & GENSEC_FEATURE_SIGN) {
1118                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1119                 if (gensec_gssapi_state->sasl
1120                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1121                         return ((gensec_gssapi_state->sasl_protection & NEG_SIGN)
1122                                 && (gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG));
1123                 }
1124                 return gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG;
1125         }
1126         if (feature & GENSEC_FEATURE_SEAL) {
1127                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1128                 if (gensec_gssapi_state->sasl
1129                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1130                         return ((gensec_gssapi_state->sasl_protection & NEG_SEAL)
1131                                  && (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG));
1132                 }
1133                 return gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG;
1134         }
1135         if (feature & GENSEC_FEATURE_SESSION_KEY) {
1136                 /* Only for GSSAPI/Krb5 */
1137                 if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
1138                         return True;
1139                 }
1140         }
1141         if (feature & GENSEC_FEATURE_DCE_STYLE) {
1142                 return gensec_gssapi_state->got_flags & GSS_C_DCE_STYLE;
1143         }
1144         /* We can always do async (rather than strict request/reply) packets.  */
1145         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1146                 return True;
1147         }
1148         return False;
1149 }
1150
1151 /*
1152  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1153  * (for encrypting some passwords).
1154  *
1155  * This breaks all the abstractions, but what do you expect...
1156  */
1157 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1158                                           DATA_BLOB *session_key)
1159 {
1160         struct gensec_gssapi_state *gensec_gssapi_state
1161                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1162         OM_uint32 maj_stat, min_stat;
1163         krb5_keyblock *subkey;
1164
1165         if (gensec_gssapi_state->session_key.data) {
1166                 *session_key = gensec_gssapi_state->session_key;
1167                 return NT_STATUS_OK;
1168         }
1169
1170         maj_stat = gsskrb5_get_initiator_subkey(&min_stat,
1171                                                 gensec_gssapi_state->gssapi_context,
1172                                                 &subkey);
1173         if (maj_stat != 0) {
1174                 DEBUG(1, ("NO session key for this mech\n"));
1175                 return NT_STATUS_NO_USER_SESSION_KEY;
1176         }
1177
1178         DEBUG(10, ("Got KRB5 session key of length %d\n",
1179                    (int)KRB5_KEY_LENGTH(subkey)));
1180         gensec_gssapi_state->session_key = data_blob_talloc(gensec_gssapi_state,
1181                                                             KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
1182         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context, subkey);
1183         *session_key = gensec_gssapi_state->session_key;
1184         dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
1185
1186         return NT_STATUS_OK;
1187 }
1188
1189 /* Get some basic (and authorization) information about the user on
1190  * this session.  This uses either the PAC (if present) or a local
1191  * database lookup */
1192 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1193                                            struct auth_session_info **_session_info)
1194 {
1195         NTSTATUS nt_status;
1196         TALLOC_CTX *mem_ctx;
1197         struct gensec_gssapi_state *gensec_gssapi_state
1198                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1199         struct auth_serversupplied_info *server_info = NULL;
1200         struct auth_session_info *session_info = NULL;
1201         struct PAC_LOGON_INFO *logon_info;
1202         OM_uint32 maj_stat, min_stat;
1203         gss_buffer_desc name_token;
1204         gss_buffer_desc pac;
1205         krb5_keyblock *keyblock;
1206         time_t authtime;
1207         krb5_principal principal;
1208         char *principal_string;
1209         DATA_BLOB pac_blob;
1210
1211         if ((gensec_gssapi_state->gss_oid->length != gss_mech_krb5->length)
1212             || (memcmp(gensec_gssapi_state->gss_oid->elements, gss_mech_krb5->elements,
1213                        gensec_gssapi_state->gss_oid->length) != 0)) {
1214                 DEBUG(1, ("NO session info available for this mech\n"));
1215                 return NT_STATUS_INVALID_PARAMETER;
1216         }
1217
1218         mem_ctx = talloc_named(gensec_gssapi_state, 0, "gensec_gssapi_session_info context");
1219         NT_STATUS_HAVE_NO_MEMORY(mem_ctx);
1220
1221         maj_stat = gss_display_name (&min_stat,
1222                                      gensec_gssapi_state->client_name,
1223                                      &name_token,
1224                                      NULL);
1225         if (GSS_ERROR(maj_stat)) {
1226                 DEBUG(1, ("GSS display_name failed: %s\n",
1227                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1228                 talloc_free(mem_ctx);
1229                 return NT_STATUS_FOOBAR;
1230         }
1231
1232         principal_string = talloc_strndup(mem_ctx, name_token.value, name_token.length);
1233
1234         gss_release_buffer(&min_stat, &name_token);
1235
1236         if (!principal_string) {
1237                 talloc_free(mem_ctx);
1238                 return NT_STATUS_NO_MEMORY;
1239         }
1240
1241         maj_stat = gsskrb5_extract_authz_data_from_sec_context(&min_stat,
1242                                                                gensec_gssapi_state->gssapi_context,
1243                                                                KRB5_AUTHDATA_WIN2K_PAC,
1244                                                                &pac);
1245
1246
1247         if (maj_stat == 0) {
1248                 pac_blob = data_blob_talloc(mem_ctx, pac.value, pac.length);
1249                 gss_release_buffer(&min_stat, &pac);
1250
1251         } else {
1252                 pac_blob = data_blob(NULL, 0);
1253         }
1254
1255         /* IF we have the PAC - otherwise we need to get this
1256          * data from elsewere - local ldb, or (TODO) lookup of some
1257          * kind...
1258          */
1259         if (pac_blob.length) {
1260                 krb5_error_code ret;
1261                 union netr_Validation validation;
1262
1263                 maj_stat = gsskrb5_extract_authtime_from_sec_context(&min_stat,
1264                                                                      gensec_gssapi_state->gssapi_context,
1265                                                                      &authtime);
1266
1267                 if (GSS_ERROR(maj_stat)) {
1268                         DEBUG(1, ("gsskrb5_extract_authtime_from_sec_context: %s\n",
1269                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1270                         talloc_free(mem_ctx);
1271                         return NT_STATUS_FOOBAR;
1272                 }
1273
1274                 maj_stat = gsskrb5_extract_service_keyblock(&min_stat,
1275                                                             gensec_gssapi_state->gssapi_context,
1276                                                             &keyblock);
1277
1278                 if (GSS_ERROR(maj_stat)) {
1279                         DEBUG(1, ("gsskrb5_copy_service_keyblock failed: %s\n",
1280                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1281                         talloc_free(mem_ctx);
1282                         return NT_STATUS_FOOBAR;
1283                 }
1284
1285                 ret = krb5_parse_name_flags(gensec_gssapi_state->smb_krb5_context->krb5_context,
1286                                             principal_string,
1287                                             KRB5_PRINCIPAL_PARSE_MUST_REALM,
1288                                             &principal);
1289                 if (ret) {
1290                         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context,
1291                                            keyblock);
1292                         talloc_free(mem_ctx);
1293                         return NT_STATUS_INVALID_PARAMETER;
1294                 }
1295
1296                 /* decode and verify the pac */
1297                 nt_status = kerberos_pac_logon_info(mem_ctx, &logon_info, pac_blob,
1298                                                     gensec_gssapi_state->smb_krb5_context->krb5_context,
1299                                                     NULL, keyblock, principal, authtime, NULL);
1300                 krb5_free_principal(gensec_gssapi_state->smb_krb5_context->krb5_context, principal);
1301                 krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context,
1302                                    keyblock);
1303
1304                 if (!NT_STATUS_IS_OK(nt_status)) {
1305                         talloc_free(mem_ctx);
1306                         return nt_status;
1307                 }
1308                 validation.sam3 = &logon_info->info3;
1309                 nt_status = make_server_info_netlogon_validation(gensec_gssapi_state,
1310                                                                  NULL,
1311                                                                  3, &validation,
1312                                                                  &server_info);
1313                 if (!NT_STATUS_IS_OK(nt_status)) {
1314                         talloc_free(mem_ctx);
1315                         return nt_status;
1316                 }
1317         } else if (!lp_parm_bool(-1, "gensec", "require_pac", False)) {
1318                 DEBUG(1, ("Unable to find PAC, resorting to local user lookup: %s\n",
1319                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1320                 nt_status = sam_get_server_info_principal(mem_ctx, principal_string,
1321                                                           &server_info);
1322
1323                 if (!NT_STATUS_IS_OK(nt_status)) {
1324                         talloc_free(mem_ctx);
1325                         return nt_status;
1326                 }
1327         } else {
1328                 DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access: %s\n",
1329                           principal_string,
1330                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1331                 return NT_STATUS_ACCESS_DENIED;
1332         }
1333
1334         /* references the server_info into the session_info */
1335         nt_status = auth_generate_session_info(mem_ctx, server_info, &session_info);
1336         if (!NT_STATUS_IS_OK(nt_status)) {
1337                 talloc_free(mem_ctx);
1338                 return nt_status;
1339         }
1340
1341         nt_status = gensec_gssapi_session_key(gensec_security, &session_info->session_key);
1342         if (!NT_STATUS_IS_OK(nt_status)) {
1343                 talloc_free(mem_ctx);
1344                 return nt_status;
1345         }
1346
1347         if (!(gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG)) {
1348                 DEBUG(10, ("gensec_gssapi: NO delegated credentials supplied by client\n"));
1349         } else {
1350                 krb5_error_code ret;
1351                 DEBUG(10, ("gensec_gssapi: delegated credentials supplied by client\n"));
1352                 session_info->credentials = cli_credentials_init(session_info);
1353                 if (!session_info->credentials) {
1354                         talloc_free(mem_ctx);
1355                         return NT_STATUS_NO_MEMORY;
1356                 }
1357
1358                 cli_credentials_set_event_context(session_info->credentials, gensec_security->event_ctx);
1359                 cli_credentials_set_conf(session_info->credentials);
1360                 /* Just so we don't segfault trying to get at a username */
1361                 cli_credentials_set_anonymous(session_info->credentials);
1362
1363                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1364                                                            gensec_gssapi_state->delegated_cred_handle,
1365                                                            CRED_SPECIFIED);
1366                 if (ret) {
1367                         talloc_free(mem_ctx);
1368                         return NT_STATUS_NO_MEMORY;
1369                 }
1370
1371                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1372                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1373
1374                 /* It has been taken from this place... */
1375                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1376         }
1377         talloc_steal(gensec_gssapi_state, session_info);
1378         talloc_free(mem_ctx);
1379         *_session_info = session_info;
1380
1381         return NT_STATUS_OK;
1382 }
1383
1384 static const char *gensec_gssapi_krb5_oids[] = {
1385         GENSEC_OID_KERBEROS5_OLD,
1386         GENSEC_OID_KERBEROS5,
1387         NULL
1388 };
1389
1390 static const char *gensec_gssapi_spnego_oids[] = {
1391         GENSEC_OID_SPNEGO,
1392         NULL
1393 };
1394
1395 /* As a server, this could in theory accept any GSSAPI mech */
1396 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1397         .name           = "gssapi_spnego",
1398         .sasl_name      = "GSS-SPNEGO",
1399         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1400         .oid            = gensec_gssapi_spnego_oids,
1401         .client_start   = gensec_gssapi_client_start,
1402         .server_start   = gensec_gssapi_server_start,
1403         .magic          = gensec_gssapi_magic,
1404         .update         = gensec_gssapi_update,
1405         .session_key    = gensec_gssapi_session_key,
1406         .session_info   = gensec_gssapi_session_info,
1407         .sign_packet    = gensec_gssapi_sign_packet,
1408         .check_packet   = gensec_gssapi_check_packet,
1409         .seal_packet    = gensec_gssapi_seal_packet,
1410         .unseal_packet  = gensec_gssapi_unseal_packet,
1411         .wrap           = gensec_gssapi_wrap,
1412         .unwrap         = gensec_gssapi_unwrap,
1413         .have_feature   = gensec_gssapi_have_feature,
1414         .enabled        = False,
1415         .kerberos       = True,
1416         .priority       = GENSEC_GSSAPI
1417 };
1418
1419 /* As a server, this could in theory accept any GSSAPI mech */
1420 static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
1421         .name           = "gssapi_krb5",
1422         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1423         .oid            = gensec_gssapi_krb5_oids,
1424         .client_start   = gensec_gssapi_client_start,
1425         .server_start   = gensec_gssapi_server_start,
1426         .magic          = gensec_gssapi_magic,
1427         .update         = gensec_gssapi_update,
1428         .session_key    = gensec_gssapi_session_key,
1429         .session_info   = gensec_gssapi_session_info,
1430         .sign_packet    = gensec_gssapi_sign_packet,
1431         .check_packet   = gensec_gssapi_check_packet,
1432         .seal_packet    = gensec_gssapi_seal_packet,
1433         .unseal_packet  = gensec_gssapi_unseal_packet,
1434         .wrap           = gensec_gssapi_wrap,
1435         .unwrap         = gensec_gssapi_unwrap,
1436         .have_feature   = gensec_gssapi_have_feature,
1437         .enabled        = True,
1438         .kerberos       = True,
1439         .priority       = GENSEC_GSSAPI
1440 };
1441
1442 /* As a server, this could in theory accept any GSSAPI mech */
1443 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1444         .name             = "gssapi_krb5_sasl",
1445         .sasl_name        = "GSSAPI",
1446         .client_start     = gensec_gssapi_sasl_client_start,
1447         .server_start     = gensec_gssapi_sasl_server_start,
1448         .update           = gensec_gssapi_update,
1449         .session_key      = gensec_gssapi_session_key,
1450         .session_info     = gensec_gssapi_session_info,
1451         .max_input_size   = gensec_gssapi_max_input_size,
1452         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1453         .wrap             = gensec_gssapi_wrap,
1454         .unwrap           = gensec_gssapi_unwrap,
1455         .have_feature     = gensec_gssapi_have_feature,
1456         .enabled          = True,
1457         .kerberos         = True,
1458         .priority         = GENSEC_GSSAPI
1459 };
1460
1461 NTSTATUS gensec_gssapi_init(void)
1462 {
1463         NTSTATUS ret;
1464
1465         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1466         if (!NT_STATUS_IS_OK(ret)) {
1467                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1468                         gensec_gssapi_spnego_security_ops.name));
1469                 return ret;
1470         }
1471
1472         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1473         if (!NT_STATUS_IS_OK(ret)) {
1474                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1475                         gensec_gssapi_krb5_security_ops.name));
1476                 return ret;
1477         }
1478
1479         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1480         if (!NT_STATUS_IS_OK(ret)) {
1481                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1482                         gensec_gssapi_sasl_krb5_security_ops.name));
1483                 return ret;
1484         }
1485
1486         return ret;
1487 }