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
 374         return NT_STATUS_OK;
 375 }
 376
 377 static NTSTATUS gensec_gssapi_sasl_client_start(struct gensec_security *gensec_security)
 378 {
 379         NTSTATUS nt_status;
 380         struct gensec_gssapi_state *gensec_gssapi_state;
 381         nt_status = gensec_gssapi_client_start(gensec_security);
 382
 383         if (NT_STATUS_IS_OK(nt_status)) {
 384                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 385                 gensec_gssapi_state->sasl = True;
 386         }
 387         return nt_status;
 388 }
 389
 390
 391 /**
 392  * Check if the packet is one for this mechansim
 393  *
 394  * @param gensec_security GENSEC state
 395  * @param in The request, as a DATA_BLOB
 396  * @return Error, INVALID_PARAMETER if it's not a packet for us
 397  *                or NT_STATUS_OK if the packet is ok.
 398  */
 399
 400 static NTSTATUS gensec_gssapi_magic(struct gensec_security *gensec_security,
 401                                     const DATA_BLOB *in)
 402 {
 403         if (gensec_gssapi_check_oid(in, GENSEC_OID_KERBEROS5)) {
 404                 return NT_STATUS_OK;
 405         } else {
 406                 return NT_STATUS_INVALID_PARAMETER;
 407         }
 408 }
 409
 410
 411 /**
 412  * Next state function for the GSSAPI GENSEC mechanism
 413  *
 414  * @param gensec_gssapi_state GSSAPI State
 415  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 416  * @param in The request, as a DATA_BLOB
 417  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 418  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 419  *                or NT_STATUS_OK if the user is authenticated.
 420  */
 421
 422 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 423                                    TALLOC_CTX *out_mem_ctx,
 424                                    const DATA_BLOB in, DATA_BLOB *out)
 425 {
 426         struct gensec_gssapi_state *gensec_gssapi_state
 427                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 428         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 429         OM_uint32 maj_stat, min_stat;
 430         OM_uint32 min_stat2;
 431         gss_buffer_desc input_token, output_token;
 432         gss_OID gss_oid_p = NULL;
 433         input_token.length = in.length;
 434         input_token.value = in.data;
 435
 436         switch (gensec_gssapi_state->sasl_state) {
 437         case STAGE_GSS_NEG:
 438         {
 439                 switch (gensec_security->gensec_role) {
 440                 case GENSEC_CLIENT:
 441                 {
 442                         maj_stat = gss_init_sec_context(&min_stat,
 443                                                         gensec_gssapi_state->client_cred->creds,
 444                                                         &gensec_gssapi_state->gssapi_context,
 445                                                         gensec_gssapi_state->server_name,
 446                                                         discard_const_p(gss_OID_desc, gensec_gssapi_state->gss_oid),
 447                                                         gensec_gssapi_state->want_flags,
 448                                                         0,
 449                                                         gensec_gssapi_state->input_chan_bindings,
 450                                                         &input_token,
 451                                                         &gss_oid_p,
 452                                                         &output_token,
 453                                                         &gensec_gssapi_state->got_flags, /* ret flags */
 454                                                         NULL);
 455                         if (gss_oid_p) {
 456                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 457                         }
 458                         break;
 459                 }
 460                 case GENSEC_SERVER:
 461                 {
 462                         maj_stat = gss_accept_sec_context(&min_stat,
 463                                                           &gensec_gssapi_state->gssapi_context,
 464                                                           gensec_gssapi_state->server_cred->creds,
 465                                                           &input_token,
 466                                                           gensec_gssapi_state->input_chan_bindings,
 467                                                           &gensec_gssapi_state->client_name,
 468                                                           &gss_oid_p,
 469                                                           &output_token,
 470                                                           &gensec_gssapi_state->got_flags,
 471                                                           NULL,
 472                                                           &gensec_gssapi_state->delegated_cred_handle);
 473                         if (gss_oid_p) {
 474                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 475                         }
 476                         break;
 477                 }
 478                 default:
 479                         return NT_STATUS_INVALID_PARAMETER;
 480
 481                 }
 482
 483                 gensec_gssapi_state->gss_exchange_count++;
 484
 485                 if (maj_stat == GSS_S_COMPLETE) {
 486                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 487                         gss_release_buffer(&min_stat2, &output_token);
 488
 489                         if (gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG) {
 490                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 491                         } else {
 492                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 493                         }
 494
 495                         /* We may have been invoked as SASL, so there
 496                          * is more work to do */
 497                         if (gensec_gssapi_state->sasl) {
 498                                 /* Due to a very subtle interaction
 499                                  * with SASL and the LDAP libs, we
 500                                  * must ensure the data pointer is
 501                                  * != NULL, but the length is 0.
 502                                  *
 503                                  * This ensures we send a 'zero
 504                                  * length' (rather than NULL) response
 505                                  */
 506
 507                                 if (!out->data) {
 508                                         out->data = (uint8_t *)talloc_strdup(out_mem_ctx, "\0");
 509                                 }
 510
 511                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 512                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 513                         } else {
 514                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 515
 516                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 517                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly sealed\n"));
 518                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 519                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly signed\n"));
 520                                 } else {
 521                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 522                                 }
 523
 524                                 return NT_STATUS_OK;
 525                         }
 526                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 527                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 528                         gss_release_buffer(&min_stat2, &output_token);
 529
 530                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 531                 } else if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
 532                         switch (min_stat) {
 533                         case KRB5_KDC_UNREACH:
 534                                 DEBUG(3, ("Cannot reach a KDC we require: %s\n",
 535                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 536                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 537                         case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 538                                 DEBUG(3, ("Server is not registered with our KDC: %s\n",
 539                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 540                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 541                         case KRB5KRB_AP_ERR_MSG_TYPE:
 542                                 /* garbage input, possibly from the auto-mech detection */
 543                                 return NT_STATUS_INVALID_PARAMETER;
 544                         default:
 545                                 DEBUG(1, ("GSS Update(krb5)(%d) Update failed: %s\n",
 546                                           gensec_gssapi_state->gss_exchange_count,
 547                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 548                                 return nt_status;
 549                         }
 550                 } else {
 551                         DEBUG(1, ("GSS Update(%d) failed: %s\n",
 552                                   gensec_gssapi_state->gss_exchange_count,
 553                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 554                         return nt_status;
 555                 }
 556                 break;
 557         }
 558
 559         /* These last two stages are only done if we were invoked as SASL */
 560         case STAGE_SASL_SSF_NEG:
 561         {
 562                 switch (gensec_security->gensec_role) {
 563                 case GENSEC_CLIENT:
 564                 {
 565                         uint8_t maxlength_proposed[4];
 566                         uint8_t maxlength_accepted[4];
 567                         uint8_t security_supported;
 568                         int conf_state;
 569                         gss_qop_t qop_state;
 570                         input_token.length = in.length;
 571                         input_token.value = in.data;
 572
 573                         /* As a client, we have just send a
 574                          * zero-length blob to the server (after the
 575                          * normal GSSAPI exchange), and it has replied
 576                          * with it's SASL negotiation */
 577
 578                         maj_stat = gss_unwrap(&min_stat,
 579                                               gensec_gssapi_state->gssapi_context,
 580                                               &input_token,
 581                                               &output_token,
 582                                               &conf_state,
 583                                               &qop_state);
 584                         if (GSS_ERROR(maj_stat)) {
 585                                 DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 586                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 587                                 return NT_STATUS_ACCESS_DENIED;
 588                         }
 589
 590                         if (output_token.length < 4) {
 591                                 return NT_STATUS_INVALID_PARAMETER;
 592                         }
 593
 594                         memcpy(maxlength_proposed, output_token.value, 4);
 595                         gss_release_buffer(&min_stat, &output_token);
 596
 597                         /* first byte is the proposed security */
 598                         security_supported = maxlength_proposed[0];
 599                         maxlength_proposed[0] = '\0';
 600
 601                         /* Rest is the proposed max wrap length */
 602                         gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_proposed, 0),
 603                                                                      gensec_gssapi_state->max_wrap_buf_size);
 604                         gensec_gssapi_state->sasl_protection = 0;
 605                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 606                                 if (security_supported & NEG_SEAL) {
 607                                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 608                                 }
 609                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 610                                 if (security_supported & NEG_SIGN) {
 611                                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 612                                 }
 613                         } else if (security_supported & NEG_NONE) {
 614                                 gensec_gssapi_state->sasl_protection |= NEG_NONE;
 615                         } else {
 616                                 DEBUG(1, ("Remote server does not support unprotected connections"));
 617                                 return NT_STATUS_ACCESS_DENIED;
 618                         }
 619
 620                         /* Send back the negotiated max length */
 621
 622                         RSIVAL(maxlength_accepted, 0, gensec_gssapi_state->max_wrap_buf_size);
 623
 624                         maxlength_accepted[0] = gensec_gssapi_state->sasl_protection;
 625
 626                         input_token.value = maxlength_accepted;
 627                         input_token.length = sizeof(maxlength_accepted);
 628
 629                         maj_stat = gss_wrap(&min_stat,
 630                                             gensec_gssapi_state->gssapi_context,
 631                                             False,
 632                                             GSS_C_QOP_DEFAULT,
 633                                             &input_token,
 634                                             &conf_state,
 635                                             &output_token);
 636                         if (GSS_ERROR(maj_stat)) {
 637                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 638                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 639                                 return NT_STATUS_ACCESS_DENIED;
 640                         }
 641
 642                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 643                         gss_release_buffer(&min_stat, &output_token);
 644
 645                         /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 646                         gensec_gssapi_state->sasl_state = STAGE_DONE;
 647
 648                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 649                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly sealed\n"));
 650                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 651                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly signed\n"));
 652                         } else {
 653                                 DEBUG(3, ("SASL/GSSAPI Connection to server will have no cryptographicly protection\n"));
 654                         }
 655
 656                         return NT_STATUS_OK;
 657                 }
 658                 case GENSEC_SERVER:
 659                 {
 660                         uint8_t maxlength_proposed[4];
 661                         uint8_t security_supported = 0x0;
 662                         int conf_state;
 663
 664                         /* As a server, we have just been sent a zero-length blob (note this, but it isn't fatal) */
 665                         if (in.length != 0) {
 666                                 DEBUG(1, ("SASL/GSSAPI: client sent non-zero length starting SASL negotiation!\n"));
 667                         }
 668
 669                         /* Give the client some idea what we will support */
 670
 671                         RSIVAL(maxlength_proposed, 0, gensec_gssapi_state->max_wrap_buf_size);
 672                         /* first byte is the proposed security */
 673                         maxlength_proposed[0] = '\0';
 674
 675                         gensec_gssapi_state->sasl_protection = 0;
 676                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 677                                 security_supported |= NEG_SEAL;
 678                         }
 679                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 680                                 security_supported |= NEG_SIGN;
 681                         }
 682                         if (security_supported == 0) {
 683                                 /* If we don't support anything, this must be 0 */
 684                                 RSIVAL(maxlength_proposed, 0, 0x0);
 685                         }
 686
 687                         /* TODO:  We may not wish to support this */
 688                         security_supported |= NEG_NONE;
 689                         maxlength_proposed[0] = security_supported;
 690
 691                         input_token.value = maxlength_proposed;
 692                         input_token.length = sizeof(maxlength_proposed);
 693
 694                         maj_stat = gss_wrap(&min_stat,
 695                                             gensec_gssapi_state->gssapi_context,
 696                                             False,
 697                                             GSS_C_QOP_DEFAULT,
 698                                             &input_token,
 699                                             &conf_state,
 700                                             &output_token);
 701                         if (GSS_ERROR(maj_stat)) {
 702                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 703                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 704                                 return NT_STATUS_ACCESS_DENIED;
 705                         }
 706
 707                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 708                         gss_release_buffer(&min_stat, &output_token);
 709
 710                         gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_ACCEPT;
 711                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 712                 }
 713                 default:
 714                         return NT_STATUS_INVALID_PARAMETER;
 715
 716                 }
 717         }
 718         /* This is s server-only stage */
 719         case STAGE_SASL_SSF_ACCEPT:
 720         {
 721                 uint8_t maxlength_accepted[4];
 722                 uint8_t security_accepted;
 723                 int conf_state;
 724                 gss_qop_t qop_state;
 725                 input_token.length = in.length;
 726                 input_token.value = in.data;
 727
 728                 maj_stat = gss_unwrap(&min_stat,
 729                                       gensec_gssapi_state->gssapi_context,
 730                                       &input_token,
 731                                       &output_token,
 732                                       &conf_state,
 733                                       &qop_state);
 734                 if (GSS_ERROR(maj_stat)) {
 735                         DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 736                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 737                         return NT_STATUS_ACCESS_DENIED;
 738                 }
 739
 740                 if (output_token.length < 4) {
 741                         return NT_STATUS_INVALID_PARAMETER;
 742                 }
 743
 744                 memcpy(maxlength_accepted, output_token.value, 4);
 745                 gss_release_buffer(&min_stat, &output_token);
 746
 747                 /* first byte is the proposed security */
 748                 security_accepted = maxlength_accepted[0];
 749                 maxlength_accepted[0] = '\0';
 750
 751                 /* Rest is the proposed max wrap length */
 752                 gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_accepted, 0),
 753                                                              gensec_gssapi_state->max_wrap_buf_size);
 754
 755                 gensec_gssapi_state->sasl_protection = 0;
 756                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 757                         if (security_accepted & NEG_SEAL) {
 758                                 gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 759                         }
 760                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 761                         if (security_accepted & NEG_SIGN) {
 762                                 gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 763                         }
 764                 } else if (security_accepted & NEG_NONE) {
 765                         gensec_gssapi_state->sasl_protection |= NEG_NONE;
 766                 } else {
 767                         DEBUG(1, ("Remote client does not support unprotected connections, but we failed to negotiate anything better"));
 768                         return NT_STATUS_ACCESS_DENIED;
 769                 }
 770
 771                 /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 772                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 773                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 774                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly sealed\n"));
 775                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 776                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly signed\n"));
 777                 } else {
 778                         DEBUG(5, ("SASL/GSSAPI Connection from client will have no cryptographic protection\n"));
 779                 }
 780
 781                 *out = data_blob(NULL, 0);
 782                 return NT_STATUS_OK;
 783         }
 784         default:
 785                 return NT_STATUS_INVALID_PARAMETER;
 786         }
 787 }
 788
 789 static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security,
 790                                    TALLOC_CTX *mem_ctx,
 791                                    const DATA_BLOB *in,
 792                                    DATA_BLOB *out)
 793 {
 794         struct gensec_gssapi_state *gensec_gssapi_state
 795                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 796         OM_uint32 maj_stat, min_stat;
 797         gss_buffer_desc input_token, output_token;
 798         int conf_state;
 799         input_token.length = in->length;
 800         input_token.value = in->data;
 801
 802         maj_stat = gss_wrap(&min_stat,
 803                             gensec_gssapi_state->gssapi_context,
 804                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 805                             GSS_C_QOP_DEFAULT,
 806                             &input_token,
 807                             &conf_state,
 808                             &output_token);
 809         if (GSS_ERROR(maj_stat)) {
 810                 DEBUG(1, ("gensec_gssapi_wrap: GSS Wrap failed: %s\n",
 811                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 812                 return NT_STATUS_ACCESS_DENIED;
 813         }
 814
 815         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 816         gss_release_buffer(&min_stat, &output_token);
 817
 818         if (gensec_gssapi_state->sasl) {
 819                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 820                 if (max_wrapped_size < out->length) {
 821                         DEBUG(1, ("gensec_gssapi_wrap: when wrapped, INPUT data (%u) is grew to be larger than SASL negotiated maximum output size (%u > %u)\n",
 822                                   (unsigned)in->length,
 823                                   (unsigned)out->length,
 824                                   (unsigned int)max_wrapped_size));
 825                         return NT_STATUS_INVALID_PARAMETER;
 826                 }
 827         }
 828
 829         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 830             && !conf_state) {
 831                 return NT_STATUS_ACCESS_DENIED;
 832         }
 833         return NT_STATUS_OK;
 834 }
 835
 836 static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security,
 837                                      TALLOC_CTX *mem_ctx,
 838                                      const DATA_BLOB *in,
 839                                      DATA_BLOB *out)
 840 {
 841         struct gensec_gssapi_state *gensec_gssapi_state
 842                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 843         OM_uint32 maj_stat, min_stat;
 844         gss_buffer_desc input_token, output_token;
 845         int conf_state;
 846         gss_qop_t qop_state;
 847         input_token.length = in->length;
 848         input_token.value = in->data;
 849
 850         if (gensec_gssapi_state->sasl) {
 851                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 852                 if (max_wrapped_size < in->length) {
 853                         DEBUG(1, ("gensec_gssapi_unwrap: WRAPPED data is larger than SASL negotiated maximum size\n"));
 854                         return NT_STATUS_INVALID_PARAMETER;
 855                 }
 856         }
 857
 858         maj_stat = gss_unwrap(&min_stat,
 859                               gensec_gssapi_state->gssapi_context,
 860                               &input_token,
 861                               &output_token,
 862                               &conf_state,
 863                               &qop_state);
 864         if (GSS_ERROR(maj_stat)) {
 865                 DEBUG(1, ("gensec_gssapi_unwrap: GSS UnWrap failed: %s\n",
 866                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 867                 return NT_STATUS_ACCESS_DENIED;
 868         }
 869
 870         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 871         gss_release_buffer(&min_stat, &output_token);
 872
 873         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 874             && !conf_state) {
 875                 return NT_STATUS_ACCESS_DENIED;
 876         }
 877         return NT_STATUS_OK;
 878 }
 879
 880 /* Find out the maximum input size negotiated on this connection */
 881
 882 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security)
 883 {
 884         struct gensec_gssapi_state *gensec_gssapi_state
 885                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 886         OM_uint32 maj_stat, min_stat;
 887         OM_uint32 max_input_size;
 888
 889         maj_stat = gss_wrap_size_limit(&min_stat,
 890                                        gensec_gssapi_state->gssapi_context,
 891                                        gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 892                                        GSS_C_QOP_DEFAULT,
 893                                        gensec_gssapi_state->max_wrap_buf_size,
 894                                        &max_input_size);
 895         if (GSS_ERROR(maj_stat)) {
 896                 TALLOC_CTX *mem_ctx = talloc_new(NULL);
 897                 DEBUG(1, ("gensec_gssapi_max_input_size: determinaing signature size with gss_wrap_size_limit failed: %s\n",
 898                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 899                 talloc_free(mem_ctx);
 900                 return 0;
 901         }
 902
 903         return max_input_size;
 904 }
 905
 906 /* Find out the maximum output size negotiated on this connection */
 907 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security)
 908 {
 909         struct gensec_gssapi_state *gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);;
 910         return gensec_gssapi_state->max_wrap_buf_size;
 911 }
 912
 913 static NTSTATUS gensec_gssapi_seal_packet(struct gensec_security *gensec_security,
 914                                           TALLOC_CTX *mem_ctx,
 915                                           uint8_t *data, size_t length,
 916                                           const uint8_t *whole_pdu, size_t pdu_length,
 917                                           DATA_BLOB *sig)
 918 {
 919         struct gensec_gssapi_state *gensec_gssapi_state
 920                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 921         OM_uint32 maj_stat, min_stat;
 922         gss_buffer_desc input_token, output_token;
 923         int conf_state;
 924         ssize_t sig_length;
 925
 926         input_token.length = length;
 927         input_token.value = data;
 928
 929         maj_stat = gss_wrap(&min_stat,
 930                             gensec_gssapi_state->gssapi_context,
 931                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 932                             GSS_C_QOP_DEFAULT,
 933                             &input_token,
 934                             &conf_state,
 935                             &output_token);
 936         if (GSS_ERROR(maj_stat)) {
 937                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap failed: %s\n",
 938                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 939                 return NT_STATUS_ACCESS_DENIED;
 940         }
 941
 942         if (output_token.length < input_token.length) {
 943                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
 944                           (long)output_token.length, (long)length));
 945                 return NT_STATUS_INTERNAL_ERROR;
 946         }
 947         sig_length = output_token.length - input_token.length;
 948
 949         memcpy(data, ((uint8_t *)output_token.value) + sig_length, length);
 950         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
 951
 952         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
 953         dump_data_pw("gensec_gssapi_seal_packet: clear\n", data, length);
 954         dump_data_pw("gensec_gssapi_seal_packet: sealed\n", ((uint8_t *)output_token.value) + sig_length, output_token.length - sig_length);
 955
 956         gss_release_buffer(&min_stat, &output_token);
 957
 958         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 959             && !conf_state) {
 960                 return NT_STATUS_ACCESS_DENIED;
 961         }
 962         return NT_STATUS_OK;
 963 }
 964
 965 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
 966                                             TALLOC_CTX *mem_ctx,
 967                                             uint8_t *data, size_t length,
 968                                             const uint8_t *whole_pdu, size_t pdu_length,
 969                                             const DATA_BLOB *sig)
 970 {
 971         struct gensec_gssapi_state *gensec_gssapi_state
 972                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 973         OM_uint32 maj_stat, min_stat;
 974         gss_buffer_desc input_token, output_token;
 975         int conf_state;
 976         gss_qop_t qop_state;
 977         DATA_BLOB in;
 978
 979         dump_data_pw("gensec_gssapi_unseal_packet: sig\n", sig->data, sig->length);
 980
 981         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
 982
 983         memcpy(in.data, sig->data, sig->length);
 984         memcpy(in.data + sig->length, data, length);
 985
 986         input_token.length = in.length;
 987         input_token.value = in.data;
 988
 989         maj_stat = gss_unwrap(&min_stat,
 990                               gensec_gssapi_state->gssapi_context,
 991                               &input_token,
 992                               &output_token,
 993                               &conf_state,
 994                               &qop_state);
 995         if (GSS_ERROR(maj_stat)) {
 996                 DEBUG(1, ("gensec_gssapi_unseal_packet: GSS UnWrap failed: %s\n",
 997                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 998                 return NT_STATUS_ACCESS_DENIED;
 999         }
1000
1001         if (output_token.length != length) {
1002                 return NT_STATUS_INTERNAL_ERROR;
1003         }
1004
1005         memcpy(data, output_token.value, length);
1006
1007         gss_release_buffer(&min_stat, &output_token);
1008
1009         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1010             && !conf_state) {
1011                 return NT_STATUS_ACCESS_DENIED;
1012         }
1013         return NT_STATUS_OK;
1014 }
1015
1016 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1017                                           TALLOC_CTX *mem_ctx,
1018                                           const uint8_t *data, size_t length,
1019                                           const uint8_t *whole_pdu, size_t pdu_length,
1020                                           DATA_BLOB *sig)
1021 {
1022         struct gensec_gssapi_state *gensec_gssapi_state
1023                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1024         OM_uint32 maj_stat, min_stat;
1025         gss_buffer_desc input_token, output_token;
1026         int conf_state;
1027         ssize_t sig_length = 0;
1028
1029         input_token.length = length;
1030         input_token.value = discard_const_p(uint8_t *, data);
1031
1032         maj_stat = gss_wrap(&min_stat,
1033                             gensec_gssapi_state->gssapi_context,
1034                             0,
1035                             GSS_C_QOP_DEFAULT,
1036                             &input_token,
1037                             &conf_state,
1038                             &output_token);
1039         if (GSS_ERROR(maj_stat)) {
1040                 DEBUG(1, ("GSS Wrap failed: %s\n",
1041                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1042                 return NT_STATUS_ACCESS_DENIED;
1043         }
1044
1045         if (output_token.length < input_token.length) {
1046                 DEBUG(1, ("gensec_gssapi_sign_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
1047                           (long)output_token.length, (long)length));
1048                 return NT_STATUS_INTERNAL_ERROR;
1049         }
1050
1051         /* Caller must pad to right boundary */
1052         sig_length = output_token.length - input_token.length;
1053
1054         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
1055
1056         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1057
1058         gss_release_buffer(&min_stat, &output_token);
1059
1060         return NT_STATUS_OK;
1061 }
1062
1063 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1064                                            TALLOC_CTX *mem_ctx,
1065                                            const uint8_t *data, size_t length,
1066                                            const uint8_t *whole_pdu, size_t pdu_length,
1067                                            const DATA_BLOB *sig)
1068 {
1069         struct gensec_gssapi_state *gensec_gssapi_state
1070                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1071         OM_uint32 maj_stat, min_stat;
1072         gss_buffer_desc input_token, output_token;
1073         int conf_state;
1074         gss_qop_t qop_state;
1075         DATA_BLOB in;
1076
1077         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1078
1079         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
1080
1081         memcpy(in.data, sig->data, sig->length);
1082         memcpy(in.data + sig->length, data, length);
1083
1084         input_token.length = in.length;
1085         input_token.value = in.data;
1086
1087         maj_stat = gss_unwrap(&min_stat,
1088                               gensec_gssapi_state->gssapi_context,
1089                               &input_token,
1090                               &output_token,
1091                               &conf_state,
1092                               &qop_state);
1093         if (GSS_ERROR(maj_stat)) {
1094                 DEBUG(1, ("GSS UnWrap failed: %s\n",
1095                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1096                 return NT_STATUS_ACCESS_DENIED;
1097         }
1098
1099         if (output_token.length != length) {
1100                 return NT_STATUS_INTERNAL_ERROR;
1101         }
1102
1103         gss_release_buffer(&min_stat, &output_token);
1104
1105         return NT_STATUS_OK;
1106 }
1107
1108 /* Try to figure out what features we actually got on the connection */
1109 static BOOL gensec_gssapi_have_feature(struct gensec_security *gensec_security,
1110                                        uint32_t feature)
1111 {
1112         struct gensec_gssapi_state *gensec_gssapi_state
1113                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1114         if (feature & GENSEC_FEATURE_SIGN) {
1115                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1116                 if (gensec_gssapi_state->sasl
1117                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1118                         return ((gensec_gssapi_state->sasl_protection & NEG_SIGN)
1119                                 && (gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG));
1120                 }
1121                 return gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG;
1122         }
1123         if (feature & GENSEC_FEATURE_SEAL) {
1124                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1125                 if (gensec_gssapi_state->sasl
1126                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1127                         return ((gensec_gssapi_state->sasl_protection & NEG_SEAL)
1128                                  && (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG));
1129                 }
1130                 return gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG;
1131         }
1132         if (feature & GENSEC_FEATURE_SESSION_KEY) {
1133                 /* Only for GSSAPI/Krb5 */
1134                 if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
1135                         return True;
1136                 }
1137         }
1138         if (feature & GENSEC_FEATURE_DCE_STYLE) {
1139                 return gensec_gssapi_state->got_flags & GSS_C_DCE_STYLE;
1140         }
1141         /* We can always do async (rather than strict request/reply) packets.  */
1142         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1143                 return True;
1144         }
1145         return False;
1146 }
1147
1148 /*
1149  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1150  * (for encrypting some passwords).
1151  *
1152  * This breaks all the abstractions, but what do you expect...
1153  */
1154 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1155                                           DATA_BLOB *session_key)
1156 {
1157         struct gensec_gssapi_state *gensec_gssapi_state
1158                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1159         OM_uint32 maj_stat, min_stat;
1160         krb5_keyblock *subkey;
1161
1162         if (gensec_gssapi_state->session_key.data) {
1163                 *session_key = gensec_gssapi_state->session_key;
1164                 return NT_STATUS_OK;
1165         }
1166
1167         maj_stat = gsskrb5_get_initiator_subkey(&min_stat,
1168                                                 gensec_gssapi_state->gssapi_context,
1169                                                 &subkey);
1170         if (maj_stat != 0) {
1171                 DEBUG(1, ("NO session key for this mech\n"));
1172                 return NT_STATUS_NO_USER_SESSION_KEY;
1173         }
1174
1175         DEBUG(10, ("Got KRB5 session key of length %d\n",
1176                    (int)KRB5_KEY_LENGTH(subkey)));
1177         gensec_gssapi_state->session_key = data_blob_talloc(gensec_gssapi_state,
1178                                                             KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
1179         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context, subkey);
1180         *session_key = gensec_gssapi_state->session_key;
1181         dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
1182
1183         return NT_STATUS_OK;
1184 }
1185
1186 /* Get some basic (and authorization) information about the user on
1187  * this session.  This uses either the PAC (if present) or a local
1188  * database lookup */
1189 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1190                                            struct auth_session_info **_session_info)
1191 {
1192         NTSTATUS nt_status;
1193         TALLOC_CTX *mem_ctx;
1194         struct gensec_gssapi_state *gensec_gssapi_state
1195                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1196         struct auth_serversupplied_info *server_info = NULL;
1197         struct auth_session_info *session_info = NULL;
1198         struct PAC_LOGON_INFO *logon_info;
1199         OM_uint32 maj_stat, min_stat;
1200         gss_buffer_desc name_token;
1201         gss_buffer_desc pac;
1202         krb5_keyblock *keyblock;
1203         time_t authtime;
1204         krb5_principal principal;
1205         char *principal_string;
1206         DATA_BLOB pac_blob;
1207
1208         if ((gensec_gssapi_state->gss_oid->length != gss_mech_krb5->length)
1209             || (memcmp(gensec_gssapi_state->gss_oid->elements, gss_mech_krb5->elements,
1210                        gensec_gssapi_state->gss_oid->length) != 0)) {
1211                 DEBUG(1, ("NO session info available for this mech\n"));
1212                 return NT_STATUS_INVALID_PARAMETER;
1213         }
1214
1215         mem_ctx = talloc_named(gensec_gssapi_state, 0, "gensec_gssapi_session_info context");
1216         NT_STATUS_HAVE_NO_MEMORY(mem_ctx);
1217
1218         maj_stat = gss_display_name (&min_stat,
1219                                      gensec_gssapi_state->client_name,
1220                                      &name_token,
1221                                      NULL);
1222         if (GSS_ERROR(maj_stat)) {
1223                 DEBUG(1, ("GSS display_name failed: %s\n",
1224                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1225                 talloc_free(mem_ctx);
1226                 return NT_STATUS_FOOBAR;
1227         }
1228
1229         principal_string = talloc_strndup(mem_ctx, name_token.value, name_token.length);
1230
1231         gss_release_buffer(&min_stat, &name_token);
1232
1233         if (!principal_string) {
1234                 talloc_free(mem_ctx);
1235                 return NT_STATUS_NO_MEMORY;
1236         }
1237
1238         maj_stat = gsskrb5_extract_authz_data_from_sec_context(&min_stat,
1239                                                                gensec_gssapi_state->gssapi_context,
1240                                                                KRB5_AUTHDATA_WIN2K_PAC,
1241                                                                &pac);
1242
1243
1244         if (maj_stat == 0) {
1245                 pac_blob = data_blob_talloc(mem_ctx, pac.value, pac.length);
1246                 gss_release_buffer(&min_stat, &pac);
1247
1248         } else {
1249                 pac_blob = data_blob(NULL, 0);
1250         }
1251
1252         /* IF we have the PAC - otherwise we need to get this
1253          * data from elsewere - local ldb, or (TODO) lookup of some
1254          * kind...
1255          */
1256         if (pac_blob.length) {
1257                 krb5_error_code ret;
1258                 union netr_Validation validation;
1259
1260                 maj_stat = gsskrb5_extract_authtime_from_sec_context(&min_stat,
1261                                                                      gensec_gssapi_state->gssapi_context,
1262                                                                      &authtime);
1263
1264                 if (GSS_ERROR(maj_stat)) {
1265                         DEBUG(1, ("gsskrb5_extract_authtime_from_sec_context: %s\n",
1266                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1267                         talloc_free(mem_ctx);
1268                         return NT_STATUS_FOOBAR;
1269                 }
1270
1271                 maj_stat = gsskrb5_extract_service_keyblock(&min_stat,
1272                                                             gensec_gssapi_state->gssapi_context,
1273                                                             &keyblock);
1274
1275                 if (GSS_ERROR(maj_stat)) {
1276                         DEBUG(1, ("gsskrb5_copy_service_keyblock failed: %s\n",
1277                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1278                         talloc_free(mem_ctx);
1279                         return NT_STATUS_FOOBAR;
1280                 }
1281
1282                 ret = krb5_parse_name_flags(gensec_gssapi_state->smb_krb5_context->krb5_context,
1283                                             principal_string,
1284                                             KRB5_PRINCIPAL_PARSE_MUST_REALM,
1285                                             &principal);
1286                 if (ret) {
1287                         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context,
1288                                            keyblock);
1289                         talloc_free(mem_ctx);
1290                         return NT_STATUS_INVALID_PARAMETER;
1291                 }
1292
1293                 /* decode and verify the pac */
1294                 nt_status = kerberos_pac_logon_info(mem_ctx, &logon_info, pac_blob,
1295                                                     gensec_gssapi_state->smb_krb5_context->krb5_context,
1296                                                     NULL, keyblock, principal, authtime, NULL);
1297                 krb5_free_principal(gensec_gssapi_state->smb_krb5_context->krb5_context, principal);
1298                 krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context,
1299                                    keyblock);
1300
1301                 if (!NT_STATUS_IS_OK(nt_status)) {
1302                         talloc_free(mem_ctx);
1303                         return nt_status;
1304                 }
1305                 validation.sam3 = &logon_info->info3;
1306                 nt_status = make_server_info_netlogon_validation(gensec_gssapi_state,
1307                                                                  NULL,
1308                                                                  3, &validation,
1309                                                                  &server_info);
1310                 if (!NT_STATUS_IS_OK(nt_status)) {
1311                         talloc_free(mem_ctx);
1312                         return nt_status;
1313                 }
1314         } else if (!lp_parm_bool(-1, "gensec", "require_pac", False)) {
1315                 DEBUG(1, ("Unable to find PAC, resorting to local user lookup: %s\n",
1316                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1317                 nt_status = sam_get_server_info_principal(mem_ctx, principal_string,
1318                                                           &server_info);
1319
1320                 if (!NT_STATUS_IS_OK(nt_status)) {
1321                         talloc_free(mem_ctx);
1322                         return nt_status;
1323                 }
1324         } else {
1325                 DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access: %s\n",
1326                           principal_string,
1327                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1328                 return NT_STATUS_ACCESS_DENIED;
1329         }
1330
1331         /* references the server_info into the session_info */
1332         nt_status = auth_generate_session_info(mem_ctx, server_info, &session_info);
1333         if (!NT_STATUS_IS_OK(nt_status)) {
1334                 talloc_free(mem_ctx);
1335                 return nt_status;
1336         }
1337
1338         nt_status = gensec_gssapi_session_key(gensec_security, &session_info->session_key);
1339         if (!NT_STATUS_IS_OK(nt_status)) {
1340                 talloc_free(mem_ctx);
1341                 return nt_status;
1342         }
1343
1344         if (!(gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG)) {
1345                 DEBUG(10, ("gensec_gssapi: NO delegated credentials supplied by client\n"));
1346         } else {
1347                 krb5_error_code ret;
1348                 DEBUG(10, ("gensec_gssapi: delegated credentials supplied by client\n"));
1349                 session_info->credentials = cli_credentials_init(session_info);
1350                 if (!session_info->credentials) {
1351                         talloc_free(mem_ctx);
1352                         return NT_STATUS_NO_MEMORY;
1353                 }
1354
1355                 cli_credentials_set_event_context(session_info->credentials, gensec_security->event_ctx);
1356                 cli_credentials_set_conf(session_info->credentials);
1357                 /* Just so we don't segfault trying to get at a username */
1358                 cli_credentials_set_anonymous(session_info->credentials);
1359
1360                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1361                                                            gensec_gssapi_state->delegated_cred_handle,
1362                                                            CRED_SPECIFIED);
1363                 if (ret) {
1364                         talloc_free(mem_ctx);
1365                         return NT_STATUS_NO_MEMORY;
1366                 }
1367
1368                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1369                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1370
1371                 /* It has been taken from this place... */
1372                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1373         }
1374         talloc_steal(gensec_gssapi_state, session_info);
1375         talloc_free(mem_ctx);
1376         *_session_info = session_info;
1377
1378         return NT_STATUS_OK;
1379 }
1380
1381 static const char *gensec_gssapi_krb5_oids[] = {
1382         GENSEC_OID_KERBEROS5_OLD,
1383         GENSEC_OID_KERBEROS5,
1384         NULL
1385 };
1386
1387 static const char *gensec_gssapi_spnego_oids[] = {
1388         GENSEC_OID_SPNEGO,
1389         NULL
1390 };
1391
1392 /* As a server, this could in theory accept any GSSAPI mech */
1393 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1394         .name           = "gssapi_spnego",
1395         .sasl_name      = "GSS-SPNEGO",
1396         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1397         .oid            = gensec_gssapi_spnego_oids,
1398         .client_start   = gensec_gssapi_client_start,
1399         .server_start   = gensec_gssapi_server_start,
1400         .magic          = gensec_gssapi_magic,
1401         .update         = gensec_gssapi_update,
1402         .session_key    = gensec_gssapi_session_key,
1403         .session_info   = gensec_gssapi_session_info,
1404         .sign_packet    = gensec_gssapi_sign_packet,
1405         .check_packet   = gensec_gssapi_check_packet,
1406         .seal_packet    = gensec_gssapi_seal_packet,
1407         .unseal_packet  = gensec_gssapi_unseal_packet,
1408         .wrap           = gensec_gssapi_wrap,
1409         .unwrap         = gensec_gssapi_unwrap,
1410         .have_feature   = gensec_gssapi_have_feature,
1411         .enabled        = False,
1412         .kerberos       = True,
1413         .priority       = GENSEC_GSSAPI
1414 };
1415
1416 /* As a server, this could in theory accept any GSSAPI mech */
1417 static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
1418         .name           = "gssapi_krb5",
1419         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1420         .oid            = gensec_gssapi_krb5_oids,
1421         .client_start   = gensec_gssapi_client_start,
1422         .server_start   = gensec_gssapi_server_start,
1423         .magic          = gensec_gssapi_magic,
1424         .update         = gensec_gssapi_update,
1425         .session_key    = gensec_gssapi_session_key,
1426         .session_info   = gensec_gssapi_session_info,
1427         .sign_packet    = gensec_gssapi_sign_packet,
1428         .check_packet   = gensec_gssapi_check_packet,
1429         .seal_packet    = gensec_gssapi_seal_packet,
1430         .unseal_packet  = gensec_gssapi_unseal_packet,
1431         .wrap           = gensec_gssapi_wrap,
1432         .unwrap         = gensec_gssapi_unwrap,
1433         .have_feature   = gensec_gssapi_have_feature,
1434         .enabled        = True,
1435         .kerberos       = True,
1436         .priority       = GENSEC_GSSAPI
1437 };
1438
1439 /* As a server, this could in theory accept any GSSAPI mech */
1440 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1441         .name             = "gssapi_krb5_sasl",
1442         .sasl_name        = "GSSAPI",
1443         .client_start     = gensec_gssapi_sasl_client_start,
1444         .server_start     = gensec_gssapi_sasl_server_start,
1445         .update           = gensec_gssapi_update,
1446         .session_key      = gensec_gssapi_session_key,
1447         .session_info     = gensec_gssapi_session_info,
1448         .max_input_size   = gensec_gssapi_max_input_size,
1449         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1450         .wrap             = gensec_gssapi_wrap,
1451         .unwrap           = gensec_gssapi_unwrap,
1452         .have_feature     = gensec_gssapi_have_feature,
1453         .enabled          = True,
1454         .kerberos         = True,
1455         .priority         = GENSEC_GSSAPI
1456 };
1457
1458 NTSTATUS gensec_gssapi_init(void)
1459 {
1460         NTSTATUS ret;
1461
1462         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1463         if (!NT_STATUS_IS_OK(ret)) {
1464                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1465                         gensec_gssapi_spnego_security_ops.name));
1466                 return ret;
1467         }
1468
1469         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1470         if (!NT_STATUS_IS_OK(ret)) {
1471                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1472                         gensec_gssapi_krb5_security_ops.name));
1473                 return ret;
1474         }
1475
1476         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1477         if (!NT_STATUS_IS_OK(ret)) {
1478                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1479                         gensec_gssapi_sasl_krb5_security_ops.name));
1480                 return ret;
1481         }
1482
1483         return ret;
1484 }