source4/auth/gensec/gensec_gssapi.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    Kerberos backend for GENSEC
   5
   6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2005
   7    Copyright (C) Stefan Metzmacher <metze@samba.org> 2004-2005
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 3 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  22 */
  23
  24 #include "includes.h"
  25 #include "lib/events/events.h"
  26 #include "system/kerberos.h"
  27 #include "auth/kerberos/kerberos.h"
  28 #include "librpc/gen_ndr/krb5pac.h"
  29 #include "auth/auth.h"
  30 #include "lib/ldb/include/ldb.h"
  31 #include "auth/auth_sam.h"
  32 #include "librpc/rpc/dcerpc.h"
  33 #include "auth/credentials/credentials.h"
  34 #include "auth/credentials/credentials_krb5.h"
  35 #include "auth/gensec/gensec.h"
  36 #include "auth/gensec/gensec_proto.h"
  37 #include "param/param.h"
  38 #include "auth/session_proto.h"
  39 #include <gssapi/gssapi.h>
  40 #include <gssapi/gssapi_krb5.h>
  41
  42 enum gensec_gssapi_sasl_state
  43 {
  44         STAGE_GSS_NEG,
  45         STAGE_SASL_SSF_NEG,
  46         STAGE_SASL_SSF_ACCEPT,
  47         STAGE_DONE
  48 };
  49
  50 #define NEG_SEAL 0x4
  51 #define NEG_SIGN 0x2
  52 #define NEG_NONE 0x1
  53
  54 struct gensec_gssapi_state {
  55         gss_ctx_id_t gssapi_context;
  56         struct gss_channel_bindings_struct *input_chan_bindings;
  57         gss_name_t server_name;
  58         gss_name_t client_name;
  59         OM_uint32 want_flags, got_flags;
  60         gss_OID gss_oid;
  61
  62         DATA_BLOB session_key;
  63         DATA_BLOB pac;
  64
  65         struct smb_krb5_context *smb_krb5_context;
  66         struct gssapi_creds_container *client_cred;
  67         struct gssapi_creds_container *server_cred;
  68
  69         gss_cred_id_t delegated_cred_handle;
  70
  71         bool sasl; /* We have two different mechs in this file: One
  72                     * for SASL wrapped GSSAPI and another for normal
  73                     * GSSAPI */
  74         enum gensec_gssapi_sasl_state sasl_state;
  75         uint8_t sasl_protection; /* What was negotiated at the SASL
  76                                   * layer, independent of the GSSAPI
  77                                   * layer... */
  78
  79         size_t max_wrap_buf_size;
  80         int gss_exchange_count;
  81         size_t sig_size;
  82 };
  83
  84 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security);
  85 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security);
  86
  87 static char *gssapi_error_string(TALLOC_CTX *mem_ctx,
  88                                  OM_uint32 maj_stat, OM_uint32 min_stat,
  89                                  const gss_OID mech)
  90 {
  91         OM_uint32 disp_min_stat, disp_maj_stat;
  92         gss_buffer_desc maj_error_message;
  93         gss_buffer_desc min_error_message;
  94         char *maj_error_string, *min_error_string;
  95         OM_uint32 msg_ctx = 0;
  96
  97         char *ret;
  98
  99         maj_error_message.value = NULL;
 100         min_error_message.value = NULL;
 101         maj_error_message.length = 0;
 102         min_error_message.length = 0;
 103
 104         disp_maj_stat = gss_display_status(&disp_min_stat, maj_stat, GSS_C_GSS_CODE,
 105                            mech, &msg_ctx, &maj_error_message);
 106         disp_maj_stat = gss_display_status(&disp_min_stat, min_stat, GSS_C_MECH_CODE,
 107                            mech, &msg_ctx, &min_error_message);
 108
 109         maj_error_string = talloc_strndup(mem_ctx, (char *)maj_error_message.value, maj_error_message.length);
 110
 111         min_error_string = talloc_strndup(mem_ctx, (char *)min_error_message.value, min_error_message.length);
 112
 113         ret = talloc_asprintf(mem_ctx, "%s: %s", maj_error_string, min_error_string);
 114
 115         talloc_free(maj_error_string);
 116         talloc_free(min_error_string);
 117
 118         gss_release_buffer(&disp_min_stat, &maj_error_message);
 119         gss_release_buffer(&disp_min_stat, &min_error_message);
 120
 121         return ret;
 122 }
 123
 124
 125 static int gensec_gssapi_destructor(struct gensec_gssapi_state *gensec_gssapi_state)
 126 {
 127         OM_uint32 maj_stat, min_stat;
 128
 129         if (gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
 130                 maj_stat = gss_release_cred(&min_stat,
 131                                             &gensec_gssapi_state->delegated_cred_handle);
 132         }
 133
 134         if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
 135                 maj_stat = gss_delete_sec_context (&min_stat,
 136                                                    &gensec_gssapi_state->gssapi_context,
 137                                                    GSS_C_NO_BUFFER);
 138         }
 139
 140         if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
 141                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->server_name);
 142         }
 143         if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
 144                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->client_name);
 145         }
 146         return 0;
 147 }
 148
 149 static NTSTATUS gensec_gssapi_start(struct gensec_security *gensec_security)
 150 {
 151         struct gensec_gssapi_state *gensec_gssapi_state;
 152         krb5_error_code ret;
 153         struct gsskrb5_send_to_kdc send_to_kdc;
 154
 155         gensec_gssapi_state = talloc(gensec_security, struct gensec_gssapi_state);
 156         if (!gensec_gssapi_state) {
 157                 return NT_STATUS_NO_MEMORY;
 158         }
 159
 160         gensec_gssapi_state->gss_exchange_count = 0;
 161         gensec_gssapi_state->max_wrap_buf_size
 162                 = lp_parm_int(gensec_security->lp_ctx, NULL, "gensec_gssapi", "max wrap buf size", 65536);
 163
 164         gensec_gssapi_state->sasl = false;
 165         gensec_gssapi_state->sasl_state = STAGE_GSS_NEG;
 166
 167         gensec_security->private_data = gensec_gssapi_state;
 168
 169         gensec_gssapi_state->gssapi_context = GSS_C_NO_CONTEXT;
 170         gensec_gssapi_state->server_name = GSS_C_NO_NAME;
 171         gensec_gssapi_state->client_name = GSS_C_NO_NAME;
 172
 173         /* TODO: Fill in channel bindings */
 174         gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
 175
 176         gensec_gssapi_state->want_flags = 0;
 177         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "mutual", true)) {
 178                 gensec_gssapi_state->want_flags |= GSS_C_MUTUAL_FLAG;
 179         }
 180         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "delegation", true)) {
 181                 gensec_gssapi_state->want_flags |= GSS_C_DELEG_FLAG;
 182         }
 183         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "replay", true)) {
 184                 gensec_gssapi_state->want_flags |= GSS_C_REPLAY_FLAG;
 185         }
 186         if (lp_parm_bool(gensec_security->lp_ctx, NULL, "gensec_gssapi", "sequence", true)) {
 187                 gensec_gssapi_state->want_flags |= GSS_C_SEQUENCE_FLAG;
 188         }
 189
 190         gensec_gssapi_state->got_flags = 0;
 191
 192         gensec_gssapi_state->session_key = data_blob(NULL, 0);
 193         gensec_gssapi_state->pac = data_blob(NULL, 0);
 194
 195         gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 196         gensec_gssapi_state->sig_size = 0;
 197
 198         talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 199
 200         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 201                 gensec_gssapi_state->want_flags |= GSS_C_INTEG_FLAG;
 202         }
 203         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 204                 gensec_gssapi_state->want_flags |= GSS_C_CONF_FLAG;
 205         }
 206         if (gensec_security->want_features & GENSEC_FEATURE_DCE_STYLE) {
 207                 gensec_gssapi_state->want_flags |= GSS_C_DCE_STYLE;
 208         }
 209
 210         gensec_gssapi_state->gss_oid = GSS_C_NULL_OID;
 211
 212         send_to_kdc.func = smb_krb5_send_and_recv_func;
 213         send_to_kdc.ptr = gensec_security->event_ctx;
 214
 215         ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
 216         if (ret) {
 217                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 218                 talloc_free(gensec_gssapi_state);
 219                 return NT_STATUS_INTERNAL_ERROR;
 220         }
 221         if (lp_realm(gensec_security->lp_ctx) && *lp_realm(gensec_security->lp_ctx)) {
 222                 char *upper_realm = strupper_talloc(gensec_gssapi_state, lp_realm(gensec_security->lp_ctx));
 223                 if (!upper_realm) {
 224                         DEBUG(1,("gensec_krb5_start: could not uppercase realm: %s\n", lp_realm(gensec_security->lp_ctx)));
 225                         talloc_free(gensec_gssapi_state);
 226                         return NT_STATUS_NO_MEMORY;
 227                 }
 228                 ret = gsskrb5_set_default_realm(upper_realm);
 229                 talloc_free(upper_realm);
 230                 if (ret) {
 231                         DEBUG(1,("gensec_krb5_start: gsskrb5_set_default_realm failed\n"));
 232                         talloc_free(gensec_gssapi_state);
 233                         return NT_STATUS_INTERNAL_ERROR;
 234                 }
 235         }
 236
 237         /* don't do DNS lookups of any kind, it might/will fail for a netbios name */
 238         ret = gsskrb5_set_dns_canonicalize(lp_parm_bool(gensec_security->lp_ctx, NULL, "krb5", "set_dns_canonicalize", false));
 239         if (ret) {
 240                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_dns_canonicalize failed\n"));
 241                 talloc_free(gensec_gssapi_state);
 242                 return NT_STATUS_INTERNAL_ERROR;
 243         }
 244
 245         ret = smb_krb5_init_context(gensec_gssapi_state,
 246                                     gensec_security->event_ctx,
 247                                     gensec_security->lp_ctx,
 248                                     &gensec_gssapi_state->smb_krb5_context);
 249         if (ret) {
 250                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n",
 251                          error_message(ret)));
 252                 talloc_free(gensec_gssapi_state);
 253                 return NT_STATUS_INTERNAL_ERROR;
 254         }
 255         return NT_STATUS_OK;
 256 }
 257
 258 static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
 259 {
 260         NTSTATUS nt_status;
 261         int ret;
 262         struct gensec_gssapi_state *gensec_gssapi_state;
 263         struct cli_credentials *machine_account;
 264         struct gssapi_creds_container *gcc;
 265
 266         nt_status = gensec_gssapi_start(gensec_security);
 267         if (!NT_STATUS_IS_OK(nt_status)) {
 268                 return nt_status;
 269         }
 270
 271         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 272
 273         machine_account = gensec_get_credentials(gensec_security);
 274
 275         if (!machine_account) {
 276                 DEBUG(3, ("No machine account credentials specified\n"));
 277                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 278         } else {
 279                 ret = cli_credentials_get_server_gss_creds(machine_account,
 280                                                            gensec_security->event_ctx,
 281                                                            gensec_security->lp_ctx, &gcc);
 282                 if (ret) {
 283                         DEBUG(1, ("Aquiring acceptor credentials failed: %s\n",
 284                                   error_message(ret)));
 285                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 286                 }
 287         }
 288
 289         gensec_gssapi_state->server_cred = gcc;
 290         return NT_STATUS_OK;
 291
 292 }
 293
 294 static NTSTATUS gensec_gssapi_sasl_server_start(struct gensec_security *gensec_security)
 295 {
 296         NTSTATUS nt_status;
 297         struct gensec_gssapi_state *gensec_gssapi_state;
 298         nt_status = gensec_gssapi_server_start(gensec_security);
 299
 300         if (NT_STATUS_IS_OK(nt_status)) {
 301                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 302                 gensec_gssapi_state->sasl = true;
 303         }
 304         return nt_status;
 305 }
 306
 307 static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
 308 {
 309         struct gensec_gssapi_state *gensec_gssapi_state;
 310         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 311         krb5_error_code ret;
 312         NTSTATUS nt_status;
 313         gss_buffer_desc name_token;
 314         gss_OID name_type;
 315         OM_uint32 maj_stat, min_stat;
 316         const char *hostname = gensec_get_target_hostname(gensec_security);
 317         const char *principal;
 318         struct gssapi_creds_container *gcc;
 319
 320         if (!hostname) {
 321                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 322                 return NT_STATUS_INVALID_PARAMETER;
 323         }
 324         if (is_ipaddress(hostname)) {
 325                 DEBUG(2, ("Cannot do GSSAPI to an IP address\n"));
 326                 return NT_STATUS_INVALID_PARAMETER;
 327         }
 328         if (strcmp(hostname, "localhost") == 0) {
 329                 DEBUG(2, ("GSSAPI to 'localhost' does not make sense\n"));
 330                 return NT_STATUS_INVALID_PARAMETER;
 331         }
 332
 333         nt_status = gensec_gssapi_start(gensec_security);
 334         if (!NT_STATUS_IS_OK(nt_status)) {
 335                 return nt_status;
 336         }
 337
 338         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 339
 340         gensec_gssapi_state->gss_oid = gss_mech_krb5;
 341
 342         principal = gensec_get_target_principal(gensec_security);
 343         if (principal && lp_client_use_spnego_principal(gensec_security->lp_ctx)) {
 344                 name_type = GSS_C_NULL_OID;
 345         } else {
 346                 principal = talloc_asprintf(gensec_gssapi_state, "%s@%s",
 347                                             gensec_get_target_service(gensec_security),
 348                                             hostname);
 349
 350                 name_type = GSS_C_NT_HOSTBASED_SERVICE;
 351         }
 352         name_token.value  = discard_const_p(uint8_t, principal);
 353         name_token.length = strlen(principal);
 354
 355
 356         maj_stat = gss_import_name (&min_stat,
 357                                     &name_token,
 358                                     name_type,
 359                                     &gensec_gssapi_state->server_name);
 360         if (maj_stat) {
 361                 DEBUG(2, ("GSS Import name of %s failed: %s\n",
 362                           (char *)name_token.value,
 363                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 364                 return NT_STATUS_INVALID_PARAMETER;
 365         }
 366
 367         ret = cli_credentials_get_client_gss_creds(creds,
 368                                                    gensec_security->event_ctx,
 369                                                    gensec_security->lp_ctx, &gcc);
 370         switch (ret) {
 371         case 0:
 372                 break;
 373         case KRB5KDC_ERR_PREAUTH_FAILED:
 374                 return NT_STATUS_LOGON_FAILURE;
 375         case KRB5_KDC_UNREACH:
 376                 DEBUG(3, ("Cannot reach a KDC we require to contact %s\n", principal));
 377                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 378         default:
 379                 DEBUG(1, ("Aquiring initiator credentials failed\n"));
 380                 return NT_STATUS_UNSUCCESSFUL;
 381         }
 382
 383         gensec_gssapi_state->client_cred = gcc;
 384         if (!talloc_reference(gensec_gssapi_state, gcc)) {
 385                 return NT_STATUS_NO_MEMORY;
 386         }
 387
 388         return NT_STATUS_OK;
 389 }
 390
 391 static NTSTATUS gensec_gssapi_sasl_client_start(struct gensec_security *gensec_security)
 392 {
 393         NTSTATUS nt_status;
 394         struct gensec_gssapi_state *gensec_gssapi_state;
 395         nt_status = gensec_gssapi_client_start(gensec_security);
 396
 397         if (NT_STATUS_IS_OK(nt_status)) {
 398                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 399                 gensec_gssapi_state->sasl = true;
 400         }
 401         return nt_status;
 402 }
 403
 404
 405 /**
 406  * Check if the packet is one for this mechansim
 407  *
 408  * @param gensec_security GENSEC state
 409  * @param in The request, as a DATA_BLOB
 410  * @return Error, INVALID_PARAMETER if it's not a packet for us
 411  *                or NT_STATUS_OK if the packet is ok.
 412  */
 413
 414 static NTSTATUS gensec_gssapi_magic(struct gensec_security *gensec_security,
 415                                     const DATA_BLOB *in)
 416 {
 417         if (gensec_gssapi_check_oid(in, GENSEC_OID_KERBEROS5)) {
 418                 return NT_STATUS_OK;
 419         } else {
 420                 return NT_STATUS_INVALID_PARAMETER;
 421         }
 422 }
 423
 424
 425 /**
 426  * Next state function for the GSSAPI GENSEC mechanism
 427  *
 428  * @param gensec_gssapi_state GSSAPI State
 429  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 430  * @param in The request, as a DATA_BLOB
 431  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 432  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 433  *                or NT_STATUS_OK if the user is authenticated.
 434  */
 435
 436 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 437                                    TALLOC_CTX *out_mem_ctx,
 438                                    const DATA_BLOB in, DATA_BLOB *out)
 439 {
 440         struct gensec_gssapi_state *gensec_gssapi_state
 441                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 442         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 443         OM_uint32 maj_stat, min_stat;
 444         OM_uint32 min_stat2;
 445         gss_buffer_desc input_token, output_token;
 446         gss_OID gss_oid_p = NULL;
 447         input_token.length = in.length;
 448         input_token.value = in.data;
 449
 450         switch (gensec_gssapi_state->sasl_state) {
 451         case STAGE_GSS_NEG:
 452         {
 453                 switch (gensec_security->gensec_role) {
 454                 case GENSEC_CLIENT:
 455                 {
 456                         maj_stat = gss_init_sec_context(&min_stat,
 457                                                         gensec_gssapi_state->client_cred->creds,
 458                                                         &gensec_gssapi_state->gssapi_context,
 459                                                         gensec_gssapi_state->server_name,
 460                                                         gensec_gssapi_state->gss_oid,
 461                                                         gensec_gssapi_state->want_flags,
 462                                                         0,
 463                                                         gensec_gssapi_state->input_chan_bindings,
 464                                                         &input_token,
 465                                                         &gss_oid_p,
 466                                                         &output_token,
 467                                                         &gensec_gssapi_state->got_flags, /* ret flags */
 468                                                         NULL);
 469                         if (gss_oid_p) {
 470                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 471                         }
 472                         break;
 473                 }
 474                 case GENSEC_SERVER:
 475                 {
 476                         maj_stat = gss_accept_sec_context(&min_stat,
 477                                                           &gensec_gssapi_state->gssapi_context,
 478                                                           gensec_gssapi_state->server_cred->creds,
 479                                                           &input_token,
 480                                                           gensec_gssapi_state->input_chan_bindings,
 481                                                           &gensec_gssapi_state->client_name,
 482                                                           &gss_oid_p,
 483                                                           &output_token,
 484                                                           &gensec_gssapi_state->got_flags,
 485                                                           NULL,
 486                                                           &gensec_gssapi_state->delegated_cred_handle);
 487                         if (gss_oid_p) {
 488                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 489                         }
 490                         break;
 491                 }
 492                 default:
 493                         return NT_STATUS_INVALID_PARAMETER;
 494
 495                 }
 496
 497                 gensec_gssapi_state->gss_exchange_count++;
 498
 499                 if (maj_stat == GSS_S_COMPLETE) {
 500                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 501                         gss_release_buffer(&min_stat2, &output_token);
 502
 503                         if (gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG) {
 504                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 505                         } else {
 506                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 507                         }
 508
 509                         /* We may have been invoked as SASL, so there
 510                          * is more work to do */
 511                         if (gensec_gssapi_state->sasl) {
 512                                 /* Due to a very subtle interaction
 513                                  * with SASL and the LDAP libs, we
 514                                  * must ensure the data pointer is
 515                                  * != NULL, but the length is 0.
 516                                  *
 517                                  * This ensures we send a 'zero
 518                                  * length' (rather than NULL) response
 519                                  */
 520
 521                                 if (!out->data) {
 522                                         out->data = (uint8_t *)talloc_strdup(out_mem_ctx, "\0");
 523                                 }
 524
 525                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 526                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 527                         } else {
 528                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 529
 530                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 531                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly sealed\n"));
 532                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 533                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly signed\n"));
 534                                 } else {
 535                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 536                                 }
 537
 538                                 return NT_STATUS_OK;
 539                         }
 540                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 541                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 542                         gss_release_buffer(&min_stat2, &output_token);
 543
 544                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 545                 } else if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
 546                         switch (min_stat) {
 547                         case KRB5_KDC_UNREACH:
 548                                 DEBUG(3, ("Cannot reach a KDC we require: %s\n",
 549                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 550                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 551                         case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 552                                 DEBUG(3, ("Server is not registered with our KDC: %s\n",
 553                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 554                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 555                         case KRB5KRB_AP_ERR_MSG_TYPE:
 556                                 /* garbage input, possibly from the auto-mech detection */
 557                                 return NT_STATUS_INVALID_PARAMETER;
 558                         default:
 559                                 DEBUG(1, ("GSS Update(krb5)(%d) Update failed: %s\n",
 560                                           gensec_gssapi_state->gss_exchange_count,
 561                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 562                                 return nt_status;
 563                         }
 564                 } else {
 565                         DEBUG(1, ("GSS Update(%d) failed: %s\n",
 566                                   gensec_gssapi_state->gss_exchange_count,
 567                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 568                         return nt_status;
 569                 }
 570                 break;
 571         }
 572
 573         /* These last two stages are only done if we were invoked as SASL */
 574         case STAGE_SASL_SSF_NEG:
 575         {
 576                 switch (gensec_security->gensec_role) {
 577                 case GENSEC_CLIENT:
 578                 {
 579                         uint8_t maxlength_proposed[4];
 580                         uint8_t maxlength_accepted[4];
 581                         uint8_t security_supported;
 582                         int conf_state;
 583                         gss_qop_t qop_state;
 584                         input_token.length = in.length;
 585                         input_token.value = in.data;
 586
 587                         /* As a client, we have just send a
 588                          * zero-length blob to the server (after the
 589                          * normal GSSAPI exchange), and it has replied
 590                          * with it's SASL negotiation */
 591
 592                         maj_stat = gss_unwrap(&min_stat,
 593                                               gensec_gssapi_state->gssapi_context,
 594                                               &input_token,
 595                                               &output_token,
 596                                               &conf_state,
 597                                               &qop_state);
 598                         if (GSS_ERROR(maj_stat)) {
 599                                 DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 600                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 601                                 return NT_STATUS_ACCESS_DENIED;
 602                         }
 603
 604                         if (output_token.length < 4) {
 605                                 return NT_STATUS_INVALID_PARAMETER;
 606                         }
 607
 608                         memcpy(maxlength_proposed, output_token.value, 4);
 609                         gss_release_buffer(&min_stat, &output_token);
 610
 611                         /* first byte is the proposed security */
 612                         security_supported = maxlength_proposed[0];
 613                         maxlength_proposed[0] = '\0';
 614
 615                         /* Rest is the proposed max wrap length */
 616                         gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_proposed, 0),
 617                                                                      gensec_gssapi_state->max_wrap_buf_size);
 618                         gensec_gssapi_state->sasl_protection = 0;
 619                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 620                                 if (security_supported & NEG_SEAL) {
 621                                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 622                                 }
 623                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 624                                 if (security_supported & NEG_SIGN) {
 625                                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 626                                 }
 627                         } else if (security_supported & NEG_NONE) {
 628                                 gensec_gssapi_state->sasl_protection |= NEG_NONE;
 629                         } else {
 630                                 DEBUG(1, ("Remote server does not support unprotected connections"));
 631                                 return NT_STATUS_ACCESS_DENIED;
 632                         }
 633
 634                         /* Send back the negotiated max length */
 635
 636                         RSIVAL(maxlength_accepted, 0, gensec_gssapi_state->max_wrap_buf_size);
 637
 638                         maxlength_accepted[0] = gensec_gssapi_state->sasl_protection;
 639
 640                         input_token.value = maxlength_accepted;
 641                         input_token.length = sizeof(maxlength_accepted);
 642
 643                         maj_stat = gss_wrap(&min_stat,
 644                                             gensec_gssapi_state->gssapi_context,
 645                                             false,
 646                                             GSS_C_QOP_DEFAULT,
 647                                             &input_token,
 648                                             &conf_state,
 649                                             &output_token);
 650                         if (GSS_ERROR(maj_stat)) {
 651                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 652                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 653                                 return NT_STATUS_ACCESS_DENIED;
 654                         }
 655
 656                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 657                         gss_release_buffer(&min_stat, &output_token);
 658
 659                         /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 660                         gensec_gssapi_state->sasl_state = STAGE_DONE;
 661
 662                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 663                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly sealed\n"));
 664                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 665                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly signed\n"));
 666                         } else {
 667                                 DEBUG(3, ("SASL/GSSAPI Connection to server will have no cryptographicly protection\n"));
 668                         }
 669
 670                         return NT_STATUS_OK;
 671                 }
 672                 case GENSEC_SERVER:
 673                 {
 674                         uint8_t maxlength_proposed[4];
 675                         uint8_t security_supported = 0x0;
 676                         int conf_state;
 677
 678                         /* As a server, we have just been sent a zero-length blob (note this, but it isn't fatal) */
 679                         if (in.length != 0) {
 680                                 DEBUG(1, ("SASL/GSSAPI: client sent non-zero length starting SASL negotiation!\n"));
 681                         }
 682
 683                         /* Give the client some idea what we will support */
 684
 685                         RSIVAL(maxlength_proposed, 0, gensec_gssapi_state->max_wrap_buf_size);
 686                         /* first byte is the proposed security */
 687                         maxlength_proposed[0] = '\0';
 688
 689                         gensec_gssapi_state->sasl_protection = 0;
 690                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 691                                 security_supported |= NEG_SEAL;
 692                         }
 693                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 694                                 security_supported |= NEG_SIGN;
 695                         }
 696                         if (security_supported == 0) {
 697                                 /* If we don't support anything, this must be 0 */
 698                                 RSIVAL(maxlength_proposed, 0, 0x0);
 699                         }
 700
 701                         /* TODO:  We may not wish to support this */
 702                         security_supported |= NEG_NONE;
 703                         maxlength_proposed[0] = security_supported;
 704
 705                         input_token.value = maxlength_proposed;
 706                         input_token.length = sizeof(maxlength_proposed);
 707
 708                         maj_stat = gss_wrap(&min_stat,
 709                                             gensec_gssapi_state->gssapi_context,
 710                                             false,
 711                                             GSS_C_QOP_DEFAULT,
 712                                             &input_token,
 713                                             &conf_state,
 714                                             &output_token);
 715                         if (GSS_ERROR(maj_stat)) {
 716                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 717                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 718                                 return NT_STATUS_ACCESS_DENIED;
 719                         }
 720
 721                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 722                         gss_release_buffer(&min_stat, &output_token);
 723
 724                         gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_ACCEPT;
 725                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 726                 }
 727                 default:
 728                         return NT_STATUS_INVALID_PARAMETER;
 729
 730                 }
 731         }
 732         /* This is s server-only stage */
 733         case STAGE_SASL_SSF_ACCEPT:
 734         {
 735                 uint8_t maxlength_accepted[4];
 736                 uint8_t security_accepted;
 737                 int conf_state;
 738                 gss_qop_t qop_state;
 739                 input_token.length = in.length;
 740                 input_token.value = in.data;
 741
 742                 maj_stat = gss_unwrap(&min_stat,
 743                                       gensec_gssapi_state->gssapi_context,
 744                                       &input_token,
 745                                       &output_token,
 746                                       &conf_state,
 747                                       &qop_state);
 748                 if (GSS_ERROR(maj_stat)) {
 749                         DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 750                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 751                         return NT_STATUS_ACCESS_DENIED;
 752                 }
 753
 754                 if (output_token.length < 4) {
 755                         return NT_STATUS_INVALID_PARAMETER;
 756                 }
 757
 758                 memcpy(maxlength_accepted, output_token.value, 4);
 759                 gss_release_buffer(&min_stat, &output_token);
 760
 761                 /* first byte is the proposed security */
 762                 security_accepted = maxlength_accepted[0];
 763                 maxlength_accepted[0] = '\0';
 764
 765                 /* Rest is the proposed max wrap length */
 766                 gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_accepted, 0),
 767                                                              gensec_gssapi_state->max_wrap_buf_size);
 768
 769                 gensec_gssapi_state->sasl_protection = 0;
 770                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 771                         if (security_accepted & NEG_SEAL) {
 772                                 gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 773                         }
 774                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 775                         if (security_accepted & NEG_SIGN) {
 776                                 gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 777                         }
 778                 } else if (security_accepted & NEG_NONE) {
 779                         gensec_gssapi_state->sasl_protection |= NEG_NONE;
 780                 } else {
 781                         DEBUG(1, ("Remote client does not support unprotected connections, but we failed to negotiate anything better"));
 782                         return NT_STATUS_ACCESS_DENIED;
 783                 }
 784
 785                 /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 786                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 787                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 788                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly sealed\n"));
 789                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 790                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly signed\n"));
 791                 } else {
 792                         DEBUG(5, ("SASL/GSSAPI Connection from client will have no cryptographic protection\n"));
 793                 }
 794
 795                 *out = data_blob(NULL, 0);
 796                 return NT_STATUS_OK;
 797         }
 798         default:
 799                 return NT_STATUS_INVALID_PARAMETER;
 800         }
 801 }
 802
 803 static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security,
 804                                    TALLOC_CTX *mem_ctx,
 805                                    const DATA_BLOB *in,
 806                                    DATA_BLOB *out)
 807 {
 808         struct gensec_gssapi_state *gensec_gssapi_state
 809                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 810         OM_uint32 maj_stat, min_stat;
 811         gss_buffer_desc input_token, output_token;
 812         int conf_state;
 813         input_token.length = in->length;
 814         input_token.value = in->data;
 815
 816         maj_stat = gss_wrap(&min_stat,
 817                             gensec_gssapi_state->gssapi_context,
 818                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 819                             GSS_C_QOP_DEFAULT,
 820                             &input_token,
 821                             &conf_state,
 822                             &output_token);
 823         if (GSS_ERROR(maj_stat)) {
 824                 DEBUG(1, ("gensec_gssapi_wrap: GSS Wrap failed: %s\n",
 825                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 826                 return NT_STATUS_ACCESS_DENIED;
 827         }
 828
 829         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 830         gss_release_buffer(&min_stat, &output_token);
 831
 832         if (gensec_gssapi_state->sasl) {
 833                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 834                 if (max_wrapped_size < out->length) {
 835                         DEBUG(1, ("gensec_gssapi_wrap: when wrapped, INPUT data (%u) is grew to be larger than SASL negotiated maximum output size (%u > %u)\n",
 836                                   (unsigned)in->length,
 837                                   (unsigned)out->length,
 838                                   (unsigned int)max_wrapped_size));
 839                         return NT_STATUS_INVALID_PARAMETER;
 840                 }
 841         }
 842
 843         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 844             && !conf_state) {
 845                 return NT_STATUS_ACCESS_DENIED;
 846         }
 847         return NT_STATUS_OK;
 848 }
 849
 850 static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security,
 851                                      TALLOC_CTX *mem_ctx,
 852                                      const DATA_BLOB *in,
 853                                      DATA_BLOB *out)
 854 {
 855         struct gensec_gssapi_state *gensec_gssapi_state
 856                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 857         OM_uint32 maj_stat, min_stat;
 858         gss_buffer_desc input_token, output_token;
 859         int conf_state;
 860         gss_qop_t qop_state;
 861         input_token.length = in->length;
 862         input_token.value = in->data;
 863
 864         if (gensec_gssapi_state->sasl) {
 865                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 866                 if (max_wrapped_size < in->length) {
 867                         DEBUG(1, ("gensec_gssapi_unwrap: WRAPPED data is larger than SASL negotiated maximum size\n"));
 868                         return NT_STATUS_INVALID_PARAMETER;
 869                 }
 870         }
 871
 872         maj_stat = gss_unwrap(&min_stat,
 873                               gensec_gssapi_state->gssapi_context,
 874                               &input_token,
 875                               &output_token,
 876                               &conf_state,
 877                               &qop_state);
 878         if (GSS_ERROR(maj_stat)) {
 879                 DEBUG(1, ("gensec_gssapi_unwrap: GSS UnWrap failed: %s\n",
 880                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 881                 return NT_STATUS_ACCESS_DENIED;
 882         }
 883
 884         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 885         gss_release_buffer(&min_stat, &output_token);
 886
 887         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 888             && !conf_state) {
 889                 return NT_STATUS_ACCESS_DENIED;
 890         }
 891         return NT_STATUS_OK;
 892 }
 893
 894 /* Find out the maximum input size negotiated on this connection */
 895
 896 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security)
 897 {
 898         struct gensec_gssapi_state *gensec_gssapi_state
 899                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 900         OM_uint32 maj_stat, min_stat;
 901         OM_uint32 max_input_size;
 902
 903         maj_stat = gss_wrap_size_limit(&min_stat,
 904                                        gensec_gssapi_state->gssapi_context,
 905                                        gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 906                                        GSS_C_QOP_DEFAULT,
 907                                        gensec_gssapi_state->max_wrap_buf_size,
 908                                        &max_input_size);
 909         if (GSS_ERROR(maj_stat)) {
 910                 TALLOC_CTX *mem_ctx = talloc_new(NULL);
 911                 DEBUG(1, ("gensec_gssapi_max_input_size: determinaing signature size with gss_wrap_size_limit failed: %s\n",
 912                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 913                 talloc_free(mem_ctx);
 914                 return 0;
 915         }
 916
 917         return max_input_size;
 918 }
 919
 920 /* Find out the maximum output size negotiated on this connection */
 921 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security)
 922 {
 923         struct gensec_gssapi_state *gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);;
 924         return gensec_gssapi_state->max_wrap_buf_size;
 925 }
 926
 927 static NTSTATUS gensec_gssapi_seal_packet(struct gensec_security *gensec_security,
 928                                           TALLOC_CTX *mem_ctx,
 929                                           uint8_t *data, size_t length,
 930                                           const uint8_t *whole_pdu, size_t pdu_length,
 931                                           DATA_BLOB *sig)
 932 {
 933         struct gensec_gssapi_state *gensec_gssapi_state
 934                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 935         OM_uint32 maj_stat, min_stat;
 936         gss_buffer_desc input_token, output_token;
 937         int conf_state;
 938         ssize_t sig_length;
 939
 940         input_token.length = length;
 941         input_token.value = data;
 942
 943         maj_stat = gss_wrap(&min_stat,
 944                             gensec_gssapi_state->gssapi_context,
 945                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 946                             GSS_C_QOP_DEFAULT,
 947                             &input_token,
 948                             &conf_state,
 949                             &output_token);
 950         if (GSS_ERROR(maj_stat)) {
 951                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap failed: %s\n",
 952                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 953                 return NT_STATUS_ACCESS_DENIED;
 954         }
 955
 956         if (output_token.length < input_token.length) {
 957                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
 958                           (long)output_token.length, (long)length));
 959                 return NT_STATUS_INTERNAL_ERROR;
 960         }
 961         sig_length = output_token.length - input_token.length;
 962
 963         memcpy(data, ((uint8_t *)output_token.value) + sig_length, length);
 964         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
 965
 966         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
 967         dump_data_pw("gensec_gssapi_seal_packet: clear\n", data, length);
 968         dump_data_pw("gensec_gssapi_seal_packet: sealed\n", ((uint8_t *)output_token.value) + sig_length, output_token.length - sig_length);
 969
 970         gss_release_buffer(&min_stat, &output_token);
 971
 972         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 973             && !conf_state) {
 974                 return NT_STATUS_ACCESS_DENIED;
 975         }
 976         return NT_STATUS_OK;
 977 }
 978
 979 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
 980                                             TALLOC_CTX *mem_ctx,
 981                                             uint8_t *data, size_t length,
 982                                             const uint8_t *whole_pdu, size_t pdu_length,
 983                                             const DATA_BLOB *sig)
 984 {
 985         struct gensec_gssapi_state *gensec_gssapi_state
 986                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 987         OM_uint32 maj_stat, min_stat;
 988         gss_buffer_desc input_token, output_token;
 989         int conf_state;
 990         gss_qop_t qop_state;
 991         DATA_BLOB in;
 992
 993         dump_data_pw("gensec_gssapi_unseal_packet: sig\n", sig->data, sig->length);
 994
 995         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
 996
 997         memcpy(in.data, sig->data, sig->length);
 998         memcpy(in.data + sig->length, data, length);
 999
1000         input_token.length = in.length;
1001         input_token.value = in.data;
1002
1003         maj_stat = gss_unwrap(&min_stat,
1004                               gensec_gssapi_state->gssapi_context,
1005                               &input_token,
1006                               &output_token,
1007                               &conf_state,
1008                               &qop_state);
1009         if (GSS_ERROR(maj_stat)) {
1010                 DEBUG(1, ("gensec_gssapi_unseal_packet: GSS UnWrap failed: %s\n",
1011                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1012                 return NT_STATUS_ACCESS_DENIED;
1013         }
1014
1015         if (output_token.length != length) {
1016                 return NT_STATUS_INTERNAL_ERROR;
1017         }
1018
1019         memcpy(data, output_token.value, length);
1020
1021         gss_release_buffer(&min_stat, &output_token);
1022
1023         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1024             && !conf_state) {
1025                 return NT_STATUS_ACCESS_DENIED;
1026         }
1027         return NT_STATUS_OK;
1028 }
1029
1030 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1031                                           TALLOC_CTX *mem_ctx,
1032                                           const uint8_t *data, size_t length,
1033                                           const uint8_t *whole_pdu, size_t pdu_length,
1034                                           DATA_BLOB *sig)
1035 {
1036         struct gensec_gssapi_state *gensec_gssapi_state
1037                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1038         OM_uint32 maj_stat, min_stat;
1039         gss_buffer_desc input_token, output_token;
1040
1041         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1042                 input_token.length = pdu_length;
1043                 input_token.value = discard_const_p(uint8_t *, whole_pdu);
1044         } else {
1045                 input_token.length = length;
1046                 input_token.value = discard_const_p(uint8_t *, data);
1047         }
1048
1049         maj_stat = gss_get_mic(&min_stat,
1050                             gensec_gssapi_state->gssapi_context,
1051                             GSS_C_QOP_DEFAULT,
1052                             &input_token,
1053                             &output_token);
1054         if (GSS_ERROR(maj_stat)) {
1055                 DEBUG(1, ("GSS GetMic failed: %s\n",
1056                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1057                 return NT_STATUS_ACCESS_DENIED;
1058         }
1059
1060         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, output_token.length);
1061
1062         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1063
1064         gss_release_buffer(&min_stat, &output_token);
1065
1066         return NT_STATUS_OK;
1067 }
1068
1069 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1070                                            TALLOC_CTX *mem_ctx,
1071                                            const uint8_t *data, size_t length,
1072                                            const uint8_t *whole_pdu, size_t pdu_length,
1073                                            const DATA_BLOB *sig)
1074 {
1075         struct gensec_gssapi_state *gensec_gssapi_state
1076                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1077         OM_uint32 maj_stat, min_stat;
1078         gss_buffer_desc input_token;
1079         gss_buffer_desc input_message;
1080         gss_qop_t qop_state;
1081
1082         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1083
1084         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1085                 input_message.length = pdu_length;
1086                 input_message.value = whole_pdu;
1087         } else {
1088                 input_message.length = length;
1089                 input_message.value = data;
1090         }
1091
1092         input_token.length = sig->length;
1093         input_token.value = sig->data;
1094
1095         maj_stat = gss_verify_mic(&min_stat,
1096                               gensec_gssapi_state->gssapi_context,
1097                               &input_message,
1098                               &input_token,
1099                               &qop_state);
1100         if (GSS_ERROR(maj_stat)) {
1101                 DEBUG(1, ("GSS VerifyMic failed: %s\n",
1102                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1103                 return NT_STATUS_ACCESS_DENIED;
1104         }
1105
1106         return NT_STATUS_OK;
1107 }
1108
1109 /* Try to figure out what features we actually got on the connection */
1110 static bool gensec_gssapi_have_feature(struct gensec_security *gensec_security,
1111                                        uint32_t feature)
1112 {
1113         struct gensec_gssapi_state *gensec_gssapi_state
1114                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1115         if (feature & GENSEC_FEATURE_SIGN) {
1116                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1117                 if (gensec_gssapi_state->sasl
1118                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1119                         return ((gensec_gssapi_state->sasl_protection & NEG_SIGN)
1120                                 && (gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG));
1121                 }
1122                 return gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG;
1123         }
1124         if (feature & GENSEC_FEATURE_SEAL) {
1125                 /* If we are going GSSAPI SASL, then we honour the second negotiation */
1126                 if (gensec_gssapi_state->sasl
1127                     && gensec_gssapi_state->sasl_state == STAGE_DONE) {
1128                         return ((gensec_gssapi_state->sasl_protection & NEG_SEAL)
1129                                  && (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG));
1130                 }
1131                 return gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG;
1132         }
1133         if (feature & GENSEC_FEATURE_SESSION_KEY) {
1134                 /* Only for GSSAPI/Krb5 */
1135                 if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
1136                         return true;
1137                 }
1138         }
1139         if (feature & GENSEC_FEATURE_DCE_STYLE) {
1140                 return gensec_gssapi_state->got_flags & GSS_C_DCE_STYLE;
1141         }
1142         /* We can always do async (rather than strict request/reply) packets.  */
1143         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1144                 return true;
1145         }
1146         return false;
1147 }
1148
1149 /*
1150  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1151  * (for encrypting some passwords).
1152  *
1153  * This breaks all the abstractions, but what do you expect...
1154  */
1155 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1156                                           DATA_BLOB *session_key)
1157 {
1158         struct gensec_gssapi_state *gensec_gssapi_state
1159                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1160         OM_uint32 maj_stat, min_stat;
1161         krb5_keyblock *subkey;
1162
1163         if (gensec_gssapi_state->session_key.data) {
1164                 *session_key = gensec_gssapi_state->session_key;
1165                 return NT_STATUS_OK;
1166         }
1167
1168         maj_stat = gsskrb5_get_subkey(&min_stat,
1169                                       gensec_gssapi_state->gssapi_context,
1170                                       &subkey);
1171         if (maj_stat != 0) {
1172                 DEBUG(1, ("NO session key for this mech\n"));
1173                 return NT_STATUS_NO_USER_SESSION_KEY;
1174         }
1175
1176         DEBUG(10, ("Got KRB5 session key of length %d\n",
1177                    (int)KRB5_KEY_LENGTH(subkey)));
1178         gensec_gssapi_state->session_key = data_blob_talloc(gensec_gssapi_state,
1179                                                             KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
1180         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context, subkey);
1181         *session_key = gensec_gssapi_state->session_key;
1182         dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
1183
1184         return NT_STATUS_OK;
1185 }
1186
1187 /* Get some basic (and authorization) information about the user on
1188  * this session.  This uses either the PAC (if present) or a local
1189  * database lookup */
1190 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1191                                            struct auth_session_info **_session_info)
1192 {
1193         NTSTATUS nt_status;
1194         TALLOC_CTX *mem_ctx;
1195         struct gensec_gssapi_state *gensec_gssapi_state
1196                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1197         struct auth_serversupplied_info *server_info = NULL;
1198         struct auth_session_info *session_info = NULL;
1199         struct PAC_LOGON_INFO *logon_info;
1200         OM_uint32 maj_stat, min_stat;
1201         gss_buffer_desc name_token;
1202         gss_buffer_desc pac;
1203         krb5_keyblock *keyblock;
1204         time_t authtime;
1205         krb5_principal principal;
1206         char *principal_string;
1207         DATA_BLOB pac_blob;
1208
1209         if ((gensec_gssapi_state->gss_oid->length != gss_mech_krb5->length)
1210             || (memcmp(gensec_gssapi_state->gss_oid->elements, gss_mech_krb5->elements,
1211                        gensec_gssapi_state->gss_oid->length) != 0)) {
1212                 DEBUG(1, ("NO session info available for this mech\n"));
1213                 return NT_STATUS_INVALID_PARAMETER;
1214         }
1215
1216         mem_ctx = talloc_named(gensec_gssapi_state, 0, "gensec_gssapi_session_info context");
1217         NT_STATUS_HAVE_NO_MEMORY(mem_ctx);
1218
1219         maj_stat = gss_display_name (&min_stat,
1220                                      gensec_gssapi_state->client_name,
1221                                      &name_token,
1222                                      NULL);
1223         if (GSS_ERROR(maj_stat)) {
1224                 DEBUG(1, ("GSS display_name failed: %s\n",
1225                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1226                 talloc_free(mem_ctx);
1227                 return NT_STATUS_FOOBAR;
1228         }
1229
1230         principal_string = talloc_strndup(mem_ctx,
1231                                           (const char *)name_token.value,
1232                                           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, lp_iconv_convenience(gensec_security->lp_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(gensec_security->lp_ctx, NULL, "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, gensec_security->event_ctx, gensec_security->lp_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, gensec_security->event_ctx, gensec_security->lp_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_conf(session_info->credentials, gensec_security->lp_ctx);
1359                 /* Just so we don't segfault trying to get at a username */
1360                 cli_credentials_set_anonymous(session_info->credentials);
1361
1362                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1363                                                            gensec_security->event_ctx,
1364                                                            gensec_security->lp_ctx,
1365                                                            gensec_gssapi_state->delegated_cred_handle,
1366                                                            CRED_SPECIFIED);
1367                 if (ret) {
1368                         talloc_free(mem_ctx);
1369                         return NT_STATUS_NO_MEMORY;
1370                 }
1371
1372                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1373                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1374
1375                 /* It has been taken from this place... */
1376                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1377         }
1378         talloc_steal(gensec_gssapi_state, session_info);
1379         talloc_free(mem_ctx);
1380         *_session_info = session_info;
1381
1382         return NT_STATUS_OK;
1383 }
1384
1385 size_t gensec_gssapi_sig_size(struct gensec_security *gensec_security, size_t data_size)
1386 {
1387         struct gensec_gssapi_state *gensec_gssapi_state
1388                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1389         OM_uint32 maj_stat, min_stat;
1390         gss_krb5_lucid_context_v1_t *lucid = NULL;
1391
1392         if (gensec_gssapi_state->sig_size) {
1393                 return gensec_gssapi_state->sig_size;
1394         }
1395
1396         if (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG) {
1397                 gensec_gssapi_state->sig_size = 45;
1398         } else {
1399                 gensec_gssapi_state->sig_size = 37;
1400         }
1401
1402         maj_stat = gss_krb5_export_lucid_sec_context(&min_stat,
1403                                                      &gensec_gssapi_state->gssapi_context,
1404                                                      1, (void **)&lucid);
1405         if (maj_stat != GSS_S_COMPLETE) {
1406                 return gensec_gssapi_state->sig_size;
1407         }
1408
1409         if (lucid->version != 1) {
1410                 return gensec_gssapi_state->sig_size;
1411         }
1412
1413         if (lucid->protocol == 1) {
1414                 if (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG) {
1415                         /*
1416                          * TODO: windows uses 76 here, but we don't know
1417                          *       gss_wrap works with aes keys yet
1418                          */
1419                         gensec_gssapi_state->sig_size = 76;
1420                 } else {
1421                         gensec_gssapi_state->sig_size = 28;
1422                 }
1423         } else if (lucid->protocol == 0) {
1424                 switch (lucid->rfc1964_kd.ctx_key.type) {
1425                 case KEYTYPE_DES:
1426                 case KEYTYPE_ARCFOUR:
1427                 case KEYTYPE_ARCFOUR_56:
1428                         if (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG) {
1429                                 gensec_gssapi_state->sig_size = 45;
1430                         } else {
1431                                 gensec_gssapi_state->sig_size = 37;
1432                         }
1433                         break;
1434                 case KEYTYPE_DES3:
1435                         if (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG) {
1436                                 gensec_gssapi_state->sig_size = 57;
1437                         } else {
1438                                 gensec_gssapi_state->sig_size = 49;
1439                         }
1440                         break;
1441                 }
1442         }
1443
1444         gss_krb5_free_lucid_sec_context(&min_stat, lucid);
1445
1446         return gensec_gssapi_state->sig_size;
1447 }
1448
1449 static const char *gensec_gssapi_krb5_oids[] = {
1450         GENSEC_OID_KERBEROS5_OLD,
1451         GENSEC_OID_KERBEROS5,
1452         NULL
1453 };
1454
1455 static const char *gensec_gssapi_spnego_oids[] = {
1456         GENSEC_OID_SPNEGO,
1457         NULL
1458 };
1459
1460 /* As a server, this could in theory accept any GSSAPI mech */
1461 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1462         .name           = "gssapi_spnego",
1463         .sasl_name      = "GSS-SPNEGO",
1464         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1465         .oid            = gensec_gssapi_spnego_oids,
1466         .client_start   = gensec_gssapi_client_start,
1467         .server_start   = gensec_gssapi_server_start,
1468         .magic          = gensec_gssapi_magic,
1469         .update         = gensec_gssapi_update,
1470         .session_key    = gensec_gssapi_session_key,
1471         .session_info   = gensec_gssapi_session_info,
1472         .sign_packet    = gensec_gssapi_sign_packet,
1473         .check_packet   = gensec_gssapi_check_packet,
1474         .seal_packet    = gensec_gssapi_seal_packet,
1475         .unseal_packet  = gensec_gssapi_unseal_packet,
1476         .wrap           = gensec_gssapi_wrap,
1477         .unwrap         = gensec_gssapi_unwrap,
1478         .have_feature   = gensec_gssapi_have_feature,
1479         .enabled        = false,
1480         .kerberos       = true,
1481         .priority       = GENSEC_GSSAPI
1482 };
1483
1484 /* As a server, this could in theory accept any GSSAPI mech */
1485 static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
1486         .name           = "gssapi_krb5",
1487         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1488         .oid            = gensec_gssapi_krb5_oids,
1489         .client_start   = gensec_gssapi_client_start,
1490         .server_start   = gensec_gssapi_server_start,
1491         .magic          = gensec_gssapi_magic,
1492         .update         = gensec_gssapi_update,
1493         .session_key    = gensec_gssapi_session_key,
1494         .session_info   = gensec_gssapi_session_info,
1495         .sig_size       = gensec_gssapi_sig_size,
1496         .sign_packet    = gensec_gssapi_sign_packet,
1497         .check_packet   = gensec_gssapi_check_packet,
1498         .seal_packet    = gensec_gssapi_seal_packet,
1499         .unseal_packet  = gensec_gssapi_unseal_packet,
1500         .wrap           = gensec_gssapi_wrap,
1501         .unwrap         = gensec_gssapi_unwrap,
1502         .have_feature   = gensec_gssapi_have_feature,
1503         .enabled        = true,
1504         .kerberos       = true,
1505         .priority       = GENSEC_GSSAPI
1506 };
1507
1508 /* As a server, this could in theory accept any GSSAPI mech */
1509 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1510         .name             = "gssapi_krb5_sasl",
1511         .sasl_name        = "GSSAPI",
1512         .client_start     = gensec_gssapi_sasl_client_start,
1513         .server_start     = gensec_gssapi_sasl_server_start,
1514         .update           = gensec_gssapi_update,
1515         .session_key      = gensec_gssapi_session_key,
1516         .session_info     = gensec_gssapi_session_info,
1517         .max_input_size   = gensec_gssapi_max_input_size,
1518         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1519         .wrap             = gensec_gssapi_wrap,
1520         .unwrap           = gensec_gssapi_unwrap,
1521         .have_feature     = gensec_gssapi_have_feature,
1522         .enabled          = true,
1523         .kerberos         = true,
1524         .priority         = GENSEC_GSSAPI
1525 };
1526
1527 _PUBLIC_ NTSTATUS gensec_gssapi_init(void)
1528 {
1529         NTSTATUS ret;
1530
1531         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1532         if (!NT_STATUS_IS_OK(ret)) {
1533                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1534                         gensec_gssapi_spnego_security_ops.name));
1535                 return ret;
1536         }
1537
1538         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1539         if (!NT_STATUS_IS_OK(ret)) {
1540                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1541                         gensec_gssapi_krb5_security_ops.name));
1542                 return ret;
1543         }
1544
1545         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1546         if (!NT_STATUS_IS_OK(ret)) {
1547                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1548                         gensec_gssapi_sasl_krb5_security_ops.name));
1549                 return ret;
1550         }
1551
1552         return ret;
1553 }