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 #include "auth/gensec/gensec_gssapi.h"
  42
  43 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security);
  44 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security);
  45
  46 static char *gssapi_error_string(TALLOC_CTX *mem_ctx,
  47                                  OM_uint32 maj_stat, OM_uint32 min_stat,
  48                                  const gss_OID mech)
  49 {
  50         OM_uint32 disp_min_stat, disp_maj_stat;
  51         gss_buffer_desc maj_error_message;
  52         gss_buffer_desc min_error_message;
  53         char *maj_error_string, *min_error_string;
  54         OM_uint32 msg_ctx = 0;
  55
  56         char *ret;
  57
  58         maj_error_message.value = NULL;
  59         min_error_message.value = NULL;
  60         maj_error_message.length = 0;
  61         min_error_message.length = 0;
  62
  63         disp_maj_stat = gss_display_status(&disp_min_stat, maj_stat, GSS_C_GSS_CODE,
  64                            mech, &msg_ctx, &maj_error_message);
  65         disp_maj_stat = gss_display_status(&disp_min_stat, min_stat, GSS_C_MECH_CODE,
  66                            mech, &msg_ctx, &min_error_message);
  67
  68         maj_error_string = talloc_strndup(mem_ctx, (char *)maj_error_message.value, maj_error_message.length);
  69
  70         min_error_string = talloc_strndup(mem_ctx, (char *)min_error_message.value, min_error_message.length);
  71
  72         ret = talloc_asprintf(mem_ctx, "%s: %s", maj_error_string, min_error_string);
  73
  74         talloc_free(maj_error_string);
  75         talloc_free(min_error_string);
  76
  77         gss_release_buffer(&disp_min_stat, &maj_error_message);
  78         gss_release_buffer(&disp_min_stat, &min_error_message);
  79
  80         return ret;
  81 }
  82
  83
  84 static int gensec_gssapi_destructor(struct gensec_gssapi_state *gensec_gssapi_state)
  85 {
  86         OM_uint32 maj_stat, min_stat;
  87
  88         if (gensec_gssapi_state->delegated_cred_handle != GSS_C_NO_CREDENTIAL) {
  89                 maj_stat = gss_release_cred(&min_stat,
  90                                             &gensec_gssapi_state->delegated_cred_handle);
  91         }
  92
  93         if (gensec_gssapi_state->gssapi_context != GSS_C_NO_CONTEXT) {
  94                 maj_stat = gss_delete_sec_context (&min_stat,
  95                                                    &gensec_gssapi_state->gssapi_context,
  96                                                    GSS_C_NO_BUFFER);
  97         }
  98
  99         if (gensec_gssapi_state->server_name != GSS_C_NO_NAME) {
 100                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->server_name);
 101         }
 102         if (gensec_gssapi_state->client_name != GSS_C_NO_NAME) {
 103                 maj_stat = gss_release_name(&min_stat, &gensec_gssapi_state->client_name);
 104         }
 105
 106         if (gensec_gssapi_state->lucid) {
 107                 gss_krb5_free_lucid_sec_context(&min_stat, gensec_gssapi_state->lucid);
 108         }
 109
 110         return 0;
 111 }
 112
 113 static NTSTATUS gensec_gssapi_init_lucid(struct gensec_gssapi_state *gensec_gssapi_state)
 114 {
 115         OM_uint32 maj_stat, min_stat;
 116
 117         if (gensec_gssapi_state->lucid) {
 118                 return NT_STATUS_OK;
 119         }
 120
 121         maj_stat = gss_krb5_export_lucid_sec_context(&min_stat,
 122                                                      &gensec_gssapi_state->gssapi_context,
 123                                                      1,
 124                                                      (void **)&gensec_gssapi_state->lucid);
 125         if (maj_stat != GSS_S_COMPLETE) {
 126                 DEBUG(0,("gensec_gssapi_init_lucid: %s\n",
 127                         gssapi_error_string(gensec_gssapi_state,
 128                                             maj_stat, min_stat,
 129                                             gensec_gssapi_state->gss_oid)));
 130                 return NT_STATUS_INTERNAL_ERROR;
 131         }
 132
 133         if (gensec_gssapi_state->lucid->version != 1) {
 134                 DEBUG(0,("gensec_gssapi_init_lucid: lucid version[%d] != 1\n",
 135                         gensec_gssapi_state->lucid->version));
 136                 gss_krb5_free_lucid_sec_context(&min_stat, gensec_gssapi_state->lucid);
 137                 gensec_gssapi_state->lucid = NULL;
 138                 return NT_STATUS_INTERNAL_ERROR;
 139         }
 140
 141         return NT_STATUS_OK;
 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                 = gensec_setting_int(gensec_security->settings, "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         gensec_gssapi_state->lucid = NULL;
 168
 169         /* TODO: Fill in channel bindings */
 170         gensec_gssapi_state->input_chan_bindings = GSS_C_NO_CHANNEL_BINDINGS;
 171
 172         gensec_gssapi_state->want_flags = 0;
 173         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation_by_kdc_policy", true)) {
 174                 gensec_gssapi_state->want_flags |= GSS_C_DELEG_POLICY_FLAG;
 175         }
 176         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "mutual", true)) {
 177                 gensec_gssapi_state->want_flags |= GSS_C_MUTUAL_FLAG;
 178         }
 179         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "delegation", true)) {
 180                 gensec_gssapi_state->want_flags |= GSS_C_DELEG_FLAG;
 181         }
 182         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "replay", true)) {
 183                 gensec_gssapi_state->want_flags |= GSS_C_REPLAY_FLAG;
 184         }
 185         if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "sequence", true)) {
 186                 gensec_gssapi_state->want_flags |= GSS_C_SEQUENCE_FLAG;
 187         }
 188
 189         gensec_gssapi_state->got_flags = 0;
 190
 191         gensec_gssapi_state->session_key = data_blob(NULL, 0);
 192         gensec_gssapi_state->pac = data_blob(NULL, 0);
 193
 194         gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 195         gensec_gssapi_state->sig_size = 0;
 196
 197         talloc_set_destructor(gensec_gssapi_state, gensec_gssapi_destructor);
 198
 199         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
 200                 gensec_gssapi_state->want_flags |= GSS_C_INTEG_FLAG;
 201         }
 202         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
 203                 gensec_gssapi_state->want_flags |= GSS_C_CONF_FLAG;
 204         }
 205         if (gensec_security->want_features & GENSEC_FEATURE_DCE_STYLE) {
 206                 gensec_gssapi_state->want_flags |= GSS_C_DCE_STYLE;
 207         }
 208
 209         gensec_gssapi_state->gss_oid = GSS_C_NULL_OID;
 210
 211         send_to_kdc.func = smb_krb5_send_and_recv_func;
 212         send_to_kdc.ptr = gensec_security->event_ctx;
 213
 214         ret = gsskrb5_set_send_to_kdc(&send_to_kdc);
 215         if (ret) {
 216                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_send_to_kdc failed\n"));
 217                 talloc_free(gensec_gssapi_state);
 218                 return NT_STATUS_INTERNAL_ERROR;
 219         }
 220         if (lp_realm(gensec_security->settings->lp_ctx) && *lp_realm(gensec_security->settings->lp_ctx)) {
 221                 char *upper_realm = strupper_talloc(gensec_gssapi_state, lp_realm(gensec_security->settings->lp_ctx));
 222                 if (!upper_realm) {
 223                         DEBUG(1,("gensec_krb5_start: could not uppercase realm: %s\n", lp_realm(gensec_security->settings->lp_ctx)));
 224                         talloc_free(gensec_gssapi_state);
 225                         return NT_STATUS_NO_MEMORY;
 226                 }
 227                 ret = gsskrb5_set_default_realm(upper_realm);
 228                 talloc_free(upper_realm);
 229                 if (ret) {
 230                         DEBUG(1,("gensec_krb5_start: gsskrb5_set_default_realm failed\n"));
 231                         talloc_free(gensec_gssapi_state);
 232                         return NT_STATUS_INTERNAL_ERROR;
 233                 }
 234         }
 235
 236         /* don't do DNS lookups of any kind, it might/will fail for a netbios name */
 237         ret = gsskrb5_set_dns_canonicalize(gensec_setting_bool(gensec_security->settings, "krb5", "set_dns_canonicalize", false));
 238         if (ret) {
 239                 DEBUG(1,("gensec_krb5_start: gsskrb5_set_dns_canonicalize failed\n"));
 240                 talloc_free(gensec_gssapi_state);
 241                 return NT_STATUS_INTERNAL_ERROR;
 242         }
 243
 244         ret = smb_krb5_init_context(gensec_gssapi_state,
 245                                     gensec_security->event_ctx,
 246                                     gensec_security->settings->lp_ctx,
 247                                     &gensec_gssapi_state->smb_krb5_context);
 248         if (ret) {
 249                 DEBUG(1,("gensec_krb5_start: krb5_init_context failed (%s)\n",
 250                          error_message(ret)));
 251                 talloc_free(gensec_gssapi_state);
 252                 return NT_STATUS_INTERNAL_ERROR;
 253         }
 254         return NT_STATUS_OK;
 255 }
 256
 257 static NTSTATUS gensec_gssapi_server_start(struct gensec_security *gensec_security)
 258 {
 259         NTSTATUS nt_status;
 260         int ret;
 261         struct gensec_gssapi_state *gensec_gssapi_state;
 262         struct cli_credentials *machine_account;
 263         struct gssapi_creds_container *gcc;
 264
 265         nt_status = gensec_gssapi_start(gensec_security);
 266         if (!NT_STATUS_IS_OK(nt_status)) {
 267                 return nt_status;
 268         }
 269
 270         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 271
 272         machine_account = gensec_get_credentials(gensec_security);
 273
 274         if (!machine_account) {
 275                 DEBUG(3, ("No machine account credentials specified\n"));
 276                 return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 277         } else {
 278                 ret = cli_credentials_get_server_gss_creds(machine_account,
 279                                                            gensec_security->event_ctx,
 280                                                            gensec_security->settings->lp_ctx, &gcc);
 281                 if (ret) {
 282                         DEBUG(1, ("Aquiring acceptor credentials failed: %s\n",
 283                                   error_message(ret)));
 284                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 285                 }
 286         }
 287
 288         gensec_gssapi_state->server_cred = gcc;
 289         return NT_STATUS_OK;
 290
 291 }
 292
 293 static NTSTATUS gensec_gssapi_sasl_server_start(struct gensec_security *gensec_security)
 294 {
 295         NTSTATUS nt_status;
 296         struct gensec_gssapi_state *gensec_gssapi_state;
 297         nt_status = gensec_gssapi_server_start(gensec_security);
 298
 299         if (NT_STATUS_IS_OK(nt_status)) {
 300                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 301                 gensec_gssapi_state->sasl = true;
 302         }
 303         return nt_status;
 304 }
 305
 306 static NTSTATUS gensec_gssapi_client_start(struct gensec_security *gensec_security)
 307 {
 308         struct gensec_gssapi_state *gensec_gssapi_state;
 309         struct cli_credentials *creds = gensec_get_credentials(gensec_security);
 310         krb5_error_code ret;
 311         NTSTATUS nt_status;
 312         gss_buffer_desc name_token;
 313         gss_OID name_type;
 314         OM_uint32 maj_stat, min_stat;
 315         const char *hostname = gensec_get_target_hostname(gensec_security);
 316         const char *principal;
 317         struct gssapi_creds_container *gcc;
 318
 319         if (!hostname) {
 320                 DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
 321                 return NT_STATUS_INVALID_PARAMETER;
 322         }
 323         if (is_ipaddress(hostname)) {
 324                 DEBUG(2, ("Cannot do GSSAPI to an IP address\n"));
 325                 return NT_STATUS_INVALID_PARAMETER;
 326         }
 327         if (strcmp(hostname, "localhost") == 0) {
 328                 DEBUG(2, ("GSSAPI to 'localhost' does not make sense\n"));
 329                 return NT_STATUS_INVALID_PARAMETER;
 330         }
 331
 332         nt_status = gensec_gssapi_start(gensec_security);
 333         if (!NT_STATUS_IS_OK(nt_status)) {
 334                 return nt_status;
 335         }
 336
 337         gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 338
 339         gensec_gssapi_state->gss_oid = gss_mech_krb5;
 340
 341         principal = gensec_get_target_principal(gensec_security);
 342         if (principal && lp_client_use_spnego_principal(gensec_security->settings->lp_ctx)) {
 343                 name_type = GSS_C_NULL_OID;
 344         } else {
 345                 principal = talloc_asprintf(gensec_gssapi_state, "%s@%s",
 346                                             gensec_get_target_service(gensec_security),
 347                                             hostname);
 348
 349                 name_type = GSS_C_NT_HOSTBASED_SERVICE;
 350         }
 351         name_token.value  = discard_const_p(uint8_t, principal);
 352         name_token.length = strlen(principal);
 353
 354
 355         maj_stat = gss_import_name (&min_stat,
 356                                     &name_token,
 357                                     name_type,
 358                                     &gensec_gssapi_state->server_name);
 359         if (maj_stat) {
 360                 DEBUG(2, ("GSS Import name of %s failed: %s\n",
 361                           (char *)name_token.value,
 362                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 363                 return NT_STATUS_INVALID_PARAMETER;
 364         }
 365
 366         ret = cli_credentials_get_client_gss_creds(creds,
 367                                                    gensec_security->event_ctx,
 368                                                    gensec_security->settings->lp_ctx, &gcc);
 369         switch (ret) {
 370         case 0:
 371                 break;
 372         case KRB5KDC_ERR_PREAUTH_FAILED:
 373                 return NT_STATUS_LOGON_FAILURE;
 374         case KRB5_KDC_UNREACH:
 375                 DEBUG(3, ("Cannot reach a KDC we require to contact %s\n", principal));
 376                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 377         default:
 378                 DEBUG(1, ("Aquiring initiator credentials failed\n"));
 379                 return NT_STATUS_UNSUCCESSFUL;
 380         }
 381
 382         gensec_gssapi_state->client_cred = gcc;
 383         if (!talloc_reference(gensec_gssapi_state, gcc)) {
 384                 return NT_STATUS_NO_MEMORY;
 385         }
 386
 387         return NT_STATUS_OK;
 388 }
 389
 390 static NTSTATUS gensec_gssapi_sasl_client_start(struct gensec_security *gensec_security)
 391 {
 392         NTSTATUS nt_status;
 393         struct gensec_gssapi_state *gensec_gssapi_state;
 394         nt_status = gensec_gssapi_client_start(gensec_security);
 395
 396         if (NT_STATUS_IS_OK(nt_status)) {
 397                 gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 398                 gensec_gssapi_state->sasl = true;
 399         }
 400         return nt_status;
 401 }
 402
 403
 404 /**
 405  * Check if the packet is one for this mechansim
 406  *
 407  * @param gensec_security GENSEC state
 408  * @param in The request, as a DATA_BLOB
 409  * @return Error, INVALID_PARAMETER if it's not a packet for us
 410  *                or NT_STATUS_OK if the packet is ok.
 411  */
 412
 413 static NTSTATUS gensec_gssapi_magic(struct gensec_security *gensec_security,
 414                                     const DATA_BLOB *in)
 415 {
 416         if (gensec_gssapi_check_oid(in, GENSEC_OID_KERBEROS5)) {
 417                 return NT_STATUS_OK;
 418         } else {
 419                 return NT_STATUS_INVALID_PARAMETER;
 420         }
 421 }
 422
 423
 424 /**
 425  * Next state function for the GSSAPI GENSEC mechanism
 426  *
 427  * @param gensec_gssapi_state GSSAPI State
 428  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
 429  * @param in The request, as a DATA_BLOB
 430  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
 431  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
 432  *                or NT_STATUS_OK if the user is authenticated.
 433  */
 434
 435 static NTSTATUS gensec_gssapi_update(struct gensec_security *gensec_security,
 436                                    TALLOC_CTX *out_mem_ctx,
 437                                    const DATA_BLOB in, DATA_BLOB *out)
 438 {
 439         struct gensec_gssapi_state *gensec_gssapi_state
 440                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 441         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 442         OM_uint32 maj_stat, min_stat;
 443         OM_uint32 min_stat2;
 444         gss_buffer_desc input_token, output_token;
 445         gss_OID gss_oid_p = NULL;
 446         input_token.length = in.length;
 447         input_token.value = in.data;
 448
 449         switch (gensec_gssapi_state->sasl_state) {
 450         case STAGE_GSS_NEG:
 451         {
 452                 switch (gensec_security->gensec_role) {
 453                 case GENSEC_CLIENT:
 454                 {
 455                         maj_stat = gss_init_sec_context(&min_stat,
 456                                                         gensec_gssapi_state->client_cred->creds,
 457                                                         &gensec_gssapi_state->gssapi_context,
 458                                                         gensec_gssapi_state->server_name,
 459                                                         gensec_gssapi_state->gss_oid,
 460                                                         gensec_gssapi_state->want_flags,
 461                                                         0,
 462                                                         gensec_gssapi_state->input_chan_bindings,
 463                                                         &input_token,
 464                                                         &gss_oid_p,
 465                                                         &output_token,
 466                                                         &gensec_gssapi_state->got_flags, /* ret flags */
 467                                                         NULL);
 468                         if (gss_oid_p) {
 469                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 470                         }
 471                         break;
 472                 }
 473                 case GENSEC_SERVER:
 474                 {
 475                         maj_stat = gss_accept_sec_context(&min_stat,
 476                                                           &gensec_gssapi_state->gssapi_context,
 477                                                           gensec_gssapi_state->server_cred->creds,
 478                                                           &input_token,
 479                                                           gensec_gssapi_state->input_chan_bindings,
 480                                                           &gensec_gssapi_state->client_name,
 481                                                           &gss_oid_p,
 482                                                           &output_token,
 483                                                           &gensec_gssapi_state->got_flags,
 484                                                           NULL,
 485                                                           &gensec_gssapi_state->delegated_cred_handle);
 486                         if (gss_oid_p) {
 487                                 gensec_gssapi_state->gss_oid = gss_oid_p;
 488                         }
 489                         break;
 490                 }
 491                 default:
 492                         return NT_STATUS_INVALID_PARAMETER;
 493
 494                 }
 495
 496                 gensec_gssapi_state->gss_exchange_count++;
 497
 498                 if (maj_stat == GSS_S_COMPLETE) {
 499                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 500                         gss_release_buffer(&min_stat2, &output_token);
 501
 502                         if (gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG) {
 503                                 DEBUG(5, ("gensec_gssapi: credentials were delegated\n"));
 504                         } else {
 505                                 DEBUG(5, ("gensec_gssapi: NO credentials were delegated\n"));
 506                         }
 507
 508                         /* We may have been invoked as SASL, so there
 509                          * is more work to do */
 510                         if (gensec_gssapi_state->sasl) {
 511                                 /* Due to a very subtle interaction
 512                                  * with SASL and the LDAP libs, we
 513                                  * must ensure the data pointer is
 514                                  * != NULL, but the length is 0.
 515                                  *
 516                                  * This ensures we send a 'zero
 517                                  * length' (rather than NULL) response
 518                                  */
 519
 520                                 if (!out->data) {
 521                                         out->data = (uint8_t *)talloc_strdup(out_mem_ctx, "\0");
 522                                 }
 523
 524                                 gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_NEG;
 525                                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
 526                         } else {
 527                                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 528
 529                                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 530                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly sealed\n"));
 531                                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 532                                         DEBUG(5, ("GSSAPI Connection will be cryptographicly signed\n"));
 533                                 } else {
 534                                         DEBUG(5, ("GSSAPI Connection will have no cryptographic protection\n"));
 535                                 }
 536
 537                                 return NT_STATUS_OK;
 538                         }
 539                 } else if (maj_stat == GSS_S_CONTINUE_NEEDED) {
 540                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 541                         gss_release_buffer(&min_stat2, &output_token);
 542
 543                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 544                 } else if (gss_oid_equal(gensec_gssapi_state->gss_oid, gss_mech_krb5)) {
 545                         switch (min_stat) {
 546                         case KRB5_KDC_UNREACH:
 547                                 DEBUG(3, ("Cannot reach a KDC we require: %s\n",
 548                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 549                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 550                         case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
 551                                 DEBUG(3, ("Server is not registered with our KDC: %s\n",
 552                                           gssapi_error_string(gensec_gssapi_state, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 553                                 return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
 554                         case KRB5KRB_AP_ERR_MSG_TYPE:
 555                                 /* garbage input, possibly from the auto-mech detection */
 556                                 return NT_STATUS_INVALID_PARAMETER;
 557                         default:
 558                                 DEBUG(1, ("GSS Update(krb5)(%d) Update failed: %s\n",
 559                                           gensec_gssapi_state->gss_exchange_count,
 560                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 561                                 return nt_status;
 562                         }
 563                 } else {
 564                         DEBUG(1, ("GSS Update(%d) failed: %s\n",
 565                                   gensec_gssapi_state->gss_exchange_count,
 566                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 567                         return nt_status;
 568                 }
 569                 break;
 570         }
 571
 572         /* These last two stages are only done if we were invoked as SASL */
 573         case STAGE_SASL_SSF_NEG:
 574         {
 575                 switch (gensec_security->gensec_role) {
 576                 case GENSEC_CLIENT:
 577                 {
 578                         uint8_t maxlength_proposed[4];
 579                         uint8_t maxlength_accepted[4];
 580                         uint8_t security_supported;
 581                         int conf_state;
 582                         gss_qop_t qop_state;
 583                         input_token.length = in.length;
 584                         input_token.value = in.data;
 585
 586                         /* As a client, we have just send a
 587                          * zero-length blob to the server (after the
 588                          * normal GSSAPI exchange), and it has replied
 589                          * with it's SASL negotiation */
 590
 591                         maj_stat = gss_unwrap(&min_stat,
 592                                               gensec_gssapi_state->gssapi_context,
 593                                               &input_token,
 594                                               &output_token,
 595                                               &conf_state,
 596                                               &qop_state);
 597                         if (GSS_ERROR(maj_stat)) {
 598                                 DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 599                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 600                                 return NT_STATUS_ACCESS_DENIED;
 601                         }
 602
 603                         if (output_token.length < 4) {
 604                                 return NT_STATUS_INVALID_PARAMETER;
 605                         }
 606
 607                         memcpy(maxlength_proposed, output_token.value, 4);
 608                         gss_release_buffer(&min_stat, &output_token);
 609
 610                         /* first byte is the proposed security */
 611                         security_supported = maxlength_proposed[0];
 612                         maxlength_proposed[0] = '\0';
 613
 614                         /* Rest is the proposed max wrap length */
 615                         gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_proposed, 0),
 616                                                                      gensec_gssapi_state->max_wrap_buf_size);
 617                         gensec_gssapi_state->sasl_protection = 0;
 618                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 619                                 if (security_supported & NEG_SEAL) {
 620                                         gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 621                                 }
 622                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 623                                 if (security_supported & NEG_SIGN) {
 624                                         gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 625                                 }
 626                         } else if (security_supported & NEG_NONE) {
 627                                 gensec_gssapi_state->sasl_protection |= NEG_NONE;
 628                         } else {
 629                                 DEBUG(1, ("Remote server does not support unprotected connections"));
 630                                 return NT_STATUS_ACCESS_DENIED;
 631                         }
 632
 633                         /* Send back the negotiated max length */
 634
 635                         RSIVAL(maxlength_accepted, 0, gensec_gssapi_state->max_wrap_buf_size);
 636
 637                         maxlength_accepted[0] = gensec_gssapi_state->sasl_protection;
 638
 639                         input_token.value = maxlength_accepted;
 640                         input_token.length = sizeof(maxlength_accepted);
 641
 642                         maj_stat = gss_wrap(&min_stat,
 643                                             gensec_gssapi_state->gssapi_context,
 644                                             false,
 645                                             GSS_C_QOP_DEFAULT,
 646                                             &input_token,
 647                                             &conf_state,
 648                                             &output_token);
 649                         if (GSS_ERROR(maj_stat)) {
 650                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 651                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 652                                 return NT_STATUS_ACCESS_DENIED;
 653                         }
 654
 655                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 656                         gss_release_buffer(&min_stat, &output_token);
 657
 658                         /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 659                         gensec_gssapi_state->sasl_state = STAGE_DONE;
 660
 661                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 662                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly sealed\n"));
 663                         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 664                                 DEBUG(3, ("SASL/GSSAPI Connection to server will be cryptographicly signed\n"));
 665                         } else {
 666                                 DEBUG(3, ("SASL/GSSAPI Connection to server will have no cryptographicly protection\n"));
 667                         }
 668
 669                         return NT_STATUS_OK;
 670                 }
 671                 case GENSEC_SERVER:
 672                 {
 673                         uint8_t maxlength_proposed[4];
 674                         uint8_t security_supported = 0x0;
 675                         int conf_state;
 676
 677                         /* As a server, we have just been sent a zero-length blob (note this, but it isn't fatal) */
 678                         if (in.length != 0) {
 679                                 DEBUG(1, ("SASL/GSSAPI: client sent non-zero length starting SASL negotiation!\n"));
 680                         }
 681
 682                         /* Give the client some idea what we will support */
 683
 684                         RSIVAL(maxlength_proposed, 0, gensec_gssapi_state->max_wrap_buf_size);
 685                         /* first byte is the proposed security */
 686                         maxlength_proposed[0] = '\0';
 687
 688                         gensec_gssapi_state->sasl_protection = 0;
 689                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 690                                 security_supported |= NEG_SEAL;
 691                         }
 692                         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 693                                 security_supported |= NEG_SIGN;
 694                         }
 695                         if (security_supported == 0) {
 696                                 /* If we don't support anything, this must be 0 */
 697                                 RSIVAL(maxlength_proposed, 0, 0x0);
 698                         }
 699
 700                         /* TODO:  We may not wish to support this */
 701                         security_supported |= NEG_NONE;
 702                         maxlength_proposed[0] = security_supported;
 703
 704                         input_token.value = maxlength_proposed;
 705                         input_token.length = sizeof(maxlength_proposed);
 706
 707                         maj_stat = gss_wrap(&min_stat,
 708                                             gensec_gssapi_state->gssapi_context,
 709                                             false,
 710                                             GSS_C_QOP_DEFAULT,
 711                                             &input_token,
 712                                             &conf_state,
 713                                             &output_token);
 714                         if (GSS_ERROR(maj_stat)) {
 715                                 DEBUG(1, ("GSS Update(SSF_NEG): GSS Wrap failed: %s\n",
 716                                           gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 717                                 return NT_STATUS_ACCESS_DENIED;
 718                         }
 719
 720                         *out = data_blob_talloc(out_mem_ctx, output_token.value, output_token.length);
 721                         gss_release_buffer(&min_stat, &output_token);
 722
 723                         gensec_gssapi_state->sasl_state = STAGE_SASL_SSF_ACCEPT;
 724                         return NT_STATUS_MORE_PROCESSING_REQUIRED;
 725                 }
 726                 default:
 727                         return NT_STATUS_INVALID_PARAMETER;
 728
 729                 }
 730         }
 731         /* This is s server-only stage */
 732         case STAGE_SASL_SSF_ACCEPT:
 733         {
 734                 uint8_t maxlength_accepted[4];
 735                 uint8_t security_accepted;
 736                 int conf_state;
 737                 gss_qop_t qop_state;
 738                 input_token.length = in.length;
 739                 input_token.value = in.data;
 740
 741                 maj_stat = gss_unwrap(&min_stat,
 742                                       gensec_gssapi_state->gssapi_context,
 743                                       &input_token,
 744                                       &output_token,
 745                                       &conf_state,
 746                                       &qop_state);
 747                 if (GSS_ERROR(maj_stat)) {
 748                         DEBUG(1, ("gensec_gssapi_update: GSS UnWrap of SASL protection negotiation failed: %s\n",
 749                                   gssapi_error_string(out_mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 750                         return NT_STATUS_ACCESS_DENIED;
 751                 }
 752
 753                 if (output_token.length < 4) {
 754                         return NT_STATUS_INVALID_PARAMETER;
 755                 }
 756
 757                 memcpy(maxlength_accepted, output_token.value, 4);
 758                 gss_release_buffer(&min_stat, &output_token);
 759
 760                 /* first byte is the proposed security */
 761                 security_accepted = maxlength_accepted[0];
 762                 maxlength_accepted[0] = '\0';
 763
 764                 /* Rest is the proposed max wrap length */
 765                 gensec_gssapi_state->max_wrap_buf_size = MIN(RIVAL(maxlength_accepted, 0),
 766                                                              gensec_gssapi_state->max_wrap_buf_size);
 767
 768                 gensec_gssapi_state->sasl_protection = 0;
 769                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 770                         if (security_accepted & NEG_SEAL) {
 771                                 gensec_gssapi_state->sasl_protection |= NEG_SEAL;
 772                         }
 773                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 774                         if (security_accepted & NEG_SIGN) {
 775                                 gensec_gssapi_state->sasl_protection |= NEG_SIGN;
 776                         }
 777                 } else if (security_accepted & NEG_NONE) {
 778                         gensec_gssapi_state->sasl_protection |= NEG_NONE;
 779                 } else {
 780                         DEBUG(1, ("Remote client does not support unprotected connections, but we failed to negotiate anything better"));
 781                         return NT_STATUS_ACCESS_DENIED;
 782                 }
 783
 784                 /* quirk:  This changes the value that gensec_have_feature returns, to be that after SASL negotiation */
 785                 gensec_gssapi_state->sasl_state = STAGE_DONE;
 786                 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
 787                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly sealed\n"));
 788                 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
 789                         DEBUG(5, ("SASL/GSSAPI Connection from client will be cryptographicly signed\n"));
 790                 } else {
 791                         DEBUG(5, ("SASL/GSSAPI Connection from client will have no cryptographic protection\n"));
 792                 }
 793
 794                 *out = data_blob(NULL, 0);
 795                 return NT_STATUS_OK;
 796         }
 797         default:
 798                 return NT_STATUS_INVALID_PARAMETER;
 799         }
 800 }
 801
 802 static NTSTATUS gensec_gssapi_wrap(struct gensec_security *gensec_security,
 803                                    TALLOC_CTX *mem_ctx,
 804                                    const DATA_BLOB *in,
 805                                    DATA_BLOB *out)
 806 {
 807         struct gensec_gssapi_state *gensec_gssapi_state
 808                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 809         OM_uint32 maj_stat, min_stat;
 810         gss_buffer_desc input_token, output_token;
 811         int conf_state;
 812         input_token.length = in->length;
 813         input_token.value = in->data;
 814
 815         maj_stat = gss_wrap(&min_stat,
 816                             gensec_gssapi_state->gssapi_context,
 817                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 818                             GSS_C_QOP_DEFAULT,
 819                             &input_token,
 820                             &conf_state,
 821                             &output_token);
 822         if (GSS_ERROR(maj_stat)) {
 823                 DEBUG(1, ("gensec_gssapi_wrap: GSS Wrap failed: %s\n",
 824                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 825                 return NT_STATUS_ACCESS_DENIED;
 826         }
 827
 828         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 829         gss_release_buffer(&min_stat, &output_token);
 830
 831         if (gensec_gssapi_state->sasl) {
 832                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 833                 if (max_wrapped_size < out->length) {
 834                         DEBUG(1, ("gensec_gssapi_wrap: when wrapped, INPUT data (%u) is grew to be larger than SASL negotiated maximum output size (%u > %u)\n",
 835                                   (unsigned)in->length,
 836                                   (unsigned)out->length,
 837                                   (unsigned int)max_wrapped_size));
 838                         return NT_STATUS_INVALID_PARAMETER;
 839                 }
 840         }
 841
 842         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 843             && !conf_state) {
 844                 return NT_STATUS_ACCESS_DENIED;
 845         }
 846         return NT_STATUS_OK;
 847 }
 848
 849 static NTSTATUS gensec_gssapi_unwrap(struct gensec_security *gensec_security,
 850                                      TALLOC_CTX *mem_ctx,
 851                                      const DATA_BLOB *in,
 852                                      DATA_BLOB *out)
 853 {
 854         struct gensec_gssapi_state *gensec_gssapi_state
 855                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 856         OM_uint32 maj_stat, min_stat;
 857         gss_buffer_desc input_token, output_token;
 858         int conf_state;
 859         gss_qop_t qop_state;
 860         input_token.length = in->length;
 861         input_token.value = in->data;
 862
 863         if (gensec_gssapi_state->sasl) {
 864                 size_t max_wrapped_size = gensec_gssapi_max_wrapped_size(gensec_security);
 865                 if (max_wrapped_size < in->length) {
 866                         DEBUG(1, ("gensec_gssapi_unwrap: WRAPPED data is larger than SASL negotiated maximum size\n"));
 867                         return NT_STATUS_INVALID_PARAMETER;
 868                 }
 869         }
 870
 871         maj_stat = gss_unwrap(&min_stat,
 872                               gensec_gssapi_state->gssapi_context,
 873                               &input_token,
 874                               &output_token,
 875                               &conf_state,
 876                               &qop_state);
 877         if (GSS_ERROR(maj_stat)) {
 878                 DEBUG(1, ("gensec_gssapi_unwrap: GSS UnWrap failed: %s\n",
 879                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 880                 return NT_STATUS_ACCESS_DENIED;
 881         }
 882
 883         *out = data_blob_talloc(mem_ctx, output_token.value, output_token.length);
 884         gss_release_buffer(&min_stat, &output_token);
 885
 886         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 887             && !conf_state) {
 888                 return NT_STATUS_ACCESS_DENIED;
 889         }
 890         return NT_STATUS_OK;
 891 }
 892
 893 /* Find out the maximum input size negotiated on this connection */
 894
 895 static size_t gensec_gssapi_max_input_size(struct gensec_security *gensec_security)
 896 {
 897         struct gensec_gssapi_state *gensec_gssapi_state
 898                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 899         OM_uint32 maj_stat, min_stat;
 900         OM_uint32 max_input_size;
 901
 902         maj_stat = gss_wrap_size_limit(&min_stat,
 903                                        gensec_gssapi_state->gssapi_context,
 904                                        gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 905                                        GSS_C_QOP_DEFAULT,
 906                                        gensec_gssapi_state->max_wrap_buf_size,
 907                                        &max_input_size);
 908         if (GSS_ERROR(maj_stat)) {
 909                 TALLOC_CTX *mem_ctx = talloc_new(NULL);
 910                 DEBUG(1, ("gensec_gssapi_max_input_size: determinaing signature size with gss_wrap_size_limit failed: %s\n",
 911                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 912                 talloc_free(mem_ctx);
 913                 return 0;
 914         }
 915
 916         return max_input_size;
 917 }
 918
 919 /* Find out the maximum output size negotiated on this connection */
 920 static size_t gensec_gssapi_max_wrapped_size(struct gensec_security *gensec_security)
 921 {
 922         struct gensec_gssapi_state *gensec_gssapi_state = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);;
 923         return gensec_gssapi_state->max_wrap_buf_size;
 924 }
 925
 926 static NTSTATUS gensec_gssapi_seal_packet(struct gensec_security *gensec_security,
 927                                           TALLOC_CTX *mem_ctx,
 928                                           uint8_t *data, size_t length,
 929                                           const uint8_t *whole_pdu, size_t pdu_length,
 930                                           DATA_BLOB *sig)
 931 {
 932         struct gensec_gssapi_state *gensec_gssapi_state
 933                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 934         OM_uint32 maj_stat, min_stat;
 935         gss_buffer_desc input_token, output_token;
 936         int conf_state;
 937         ssize_t sig_length;
 938
 939         input_token.length = length;
 940         input_token.value = data;
 941
 942         maj_stat = gss_wrap(&min_stat,
 943                             gensec_gssapi_state->gssapi_context,
 944                             gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL),
 945                             GSS_C_QOP_DEFAULT,
 946                             &input_token,
 947                             &conf_state,
 948                             &output_token);
 949         if (GSS_ERROR(maj_stat)) {
 950                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap failed: %s\n",
 951                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
 952                 return NT_STATUS_ACCESS_DENIED;
 953         }
 954
 955         if (output_token.length < input_token.length) {
 956                 DEBUG(1, ("gensec_gssapi_seal_packet: GSS Wrap length [%ld] *less* than caller length [%ld]\n",
 957                           (long)output_token.length, (long)length));
 958                 return NT_STATUS_INTERNAL_ERROR;
 959         }
 960         sig_length = output_token.length - input_token.length;
 961
 962         memcpy(data, ((uint8_t *)output_token.value) + sig_length, length);
 963         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, sig_length);
 964
 965         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
 966         dump_data_pw("gensec_gssapi_seal_packet: clear\n", data, length);
 967         dump_data_pw("gensec_gssapi_seal_packet: sealed\n", ((uint8_t *)output_token.value) + sig_length, output_token.length - sig_length);
 968
 969         gss_release_buffer(&min_stat, &output_token);
 970
 971         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
 972             && !conf_state) {
 973                 return NT_STATUS_ACCESS_DENIED;
 974         }
 975         return NT_STATUS_OK;
 976 }
 977
 978 static NTSTATUS gensec_gssapi_unseal_packet(struct gensec_security *gensec_security,
 979                                             TALLOC_CTX *mem_ctx,
 980                                             uint8_t *data, size_t length,
 981                                             const uint8_t *whole_pdu, size_t pdu_length,
 982                                             const DATA_BLOB *sig)
 983 {
 984         struct gensec_gssapi_state *gensec_gssapi_state
 985                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
 986         OM_uint32 maj_stat, min_stat;
 987         gss_buffer_desc input_token, output_token;
 988         int conf_state;
 989         gss_qop_t qop_state;
 990         DATA_BLOB in;
 991
 992         dump_data_pw("gensec_gssapi_unseal_packet: sig\n", sig->data, sig->length);
 993
 994         in = data_blob_talloc(mem_ctx, NULL, sig->length + length);
 995
 996         memcpy(in.data, sig->data, sig->length);
 997         memcpy(in.data + sig->length, data, length);
 998
 999         input_token.length = in.length;
1000         input_token.value = in.data;
1001
1002         maj_stat = gss_unwrap(&min_stat,
1003                               gensec_gssapi_state->gssapi_context,
1004                               &input_token,
1005                               &output_token,
1006                               &conf_state,
1007                               &qop_state);
1008         if (GSS_ERROR(maj_stat)) {
1009                 DEBUG(1, ("gensec_gssapi_unseal_packet: GSS UnWrap failed: %s\n",
1010                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1011                 return NT_STATUS_ACCESS_DENIED;
1012         }
1013
1014         if (output_token.length != length) {
1015                 return NT_STATUS_INTERNAL_ERROR;
1016         }
1017
1018         memcpy(data, output_token.value, length);
1019
1020         gss_release_buffer(&min_stat, &output_token);
1021
1022         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)
1023             && !conf_state) {
1024                 return NT_STATUS_ACCESS_DENIED;
1025         }
1026         return NT_STATUS_OK;
1027 }
1028
1029 static NTSTATUS gensec_gssapi_sign_packet(struct gensec_security *gensec_security,
1030                                           TALLOC_CTX *mem_ctx,
1031                                           const uint8_t *data, size_t length,
1032                                           const uint8_t *whole_pdu, size_t pdu_length,
1033                                           DATA_BLOB *sig)
1034 {
1035         struct gensec_gssapi_state *gensec_gssapi_state
1036                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1037         OM_uint32 maj_stat, min_stat;
1038         gss_buffer_desc input_token, output_token;
1039
1040         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1041                 input_token.length = pdu_length;
1042                 input_token.value = discard_const_p(uint8_t *, whole_pdu);
1043         } else {
1044                 input_token.length = length;
1045                 input_token.value = discard_const_p(uint8_t *, data);
1046         }
1047
1048         maj_stat = gss_get_mic(&min_stat,
1049                             gensec_gssapi_state->gssapi_context,
1050                             GSS_C_QOP_DEFAULT,
1051                             &input_token,
1052                             &output_token);
1053         if (GSS_ERROR(maj_stat)) {
1054                 DEBUG(1, ("GSS GetMic failed: %s\n",
1055                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1056                 return NT_STATUS_ACCESS_DENIED;
1057         }
1058
1059         *sig = data_blob_talloc(mem_ctx, (uint8_t *)output_token.value, output_token.length);
1060
1061         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1062
1063         gss_release_buffer(&min_stat, &output_token);
1064
1065         return NT_STATUS_OK;
1066 }
1067
1068 static NTSTATUS gensec_gssapi_check_packet(struct gensec_security *gensec_security,
1069                                            TALLOC_CTX *mem_ctx,
1070                                            const uint8_t *data, size_t length,
1071                                            const uint8_t *whole_pdu, size_t pdu_length,
1072                                            const DATA_BLOB *sig)
1073 {
1074         struct gensec_gssapi_state *gensec_gssapi_state
1075                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1076         OM_uint32 maj_stat, min_stat;
1077         gss_buffer_desc input_token;
1078         gss_buffer_desc input_message;
1079         gss_qop_t qop_state;
1080
1081         dump_data_pw("gensec_gssapi_seal_packet: sig\n", sig->data, sig->length);
1082
1083         if (gensec_security->want_features & GENSEC_FEATURE_SIGN_PKT_HEADER) {
1084                 input_message.length = pdu_length;
1085                 input_message.value = discard_const(whole_pdu);
1086         } else {
1087                 input_message.length = length;
1088                 input_message.value = discard_const(data);
1089         }
1090
1091         input_token.length = sig->length;
1092         input_token.value = sig->data;
1093
1094         maj_stat = gss_verify_mic(&min_stat,
1095                               gensec_gssapi_state->gssapi_context,
1096                               &input_message,
1097                               &input_token,
1098                               &qop_state);
1099         if (GSS_ERROR(maj_stat)) {
1100                 DEBUG(1, ("GSS VerifyMic failed: %s\n",
1101                           gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1102                 return NT_STATUS_ACCESS_DENIED;
1103         }
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         if (feature & GENSEC_FEATURE_NEW_SPNEGO) {
1142                 NTSTATUS status;
1143
1144                 if (!(gensec_gssapi_state->got_flags & GSS_C_INTEG_FLAG)) {
1145                         return false;
1146                 }
1147
1148                 if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "force_new_spnego", false)) {
1149                         return true;
1150                 }
1151                 if (gensec_setting_bool(gensec_security->settings, "gensec_gssapi", "disable_new_spnego", false)) {
1152                         return false;
1153                 }
1154
1155                 status = gensec_gssapi_init_lucid(gensec_gssapi_state);
1156                 if (!NT_STATUS_IS_OK(status)) {
1157                         return false;
1158                 }
1159
1160                 if (gensec_gssapi_state->lucid->protocol == 1) {
1161                         return true;
1162                 }
1163
1164                 return false;
1165         }
1166         /* We can always do async (rather than strict request/reply) packets.  */
1167         if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
1168                 return true;
1169         }
1170         return false;
1171 }
1172
1173 /*
1174  * Extract the 'sesssion key' needed by SMB signing and ncacn_np
1175  * (for encrypting some passwords).
1176  *
1177  * This breaks all the abstractions, but what do you expect...
1178  */
1179 static NTSTATUS gensec_gssapi_session_key(struct gensec_security *gensec_security,
1180                                           DATA_BLOB *session_key)
1181 {
1182         struct gensec_gssapi_state *gensec_gssapi_state
1183                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1184         OM_uint32 maj_stat, min_stat;
1185         krb5_keyblock *subkey;
1186
1187         if (gensec_gssapi_state->sasl_state != STAGE_DONE) {
1188                 return NT_STATUS_NO_USER_SESSION_KEY;
1189         }
1190
1191         if (gensec_gssapi_state->session_key.data) {
1192                 *session_key = gensec_gssapi_state->session_key;
1193                 return NT_STATUS_OK;
1194         }
1195
1196         maj_stat = gsskrb5_get_subkey(&min_stat,
1197                                       gensec_gssapi_state->gssapi_context,
1198                                       &subkey);
1199         if (maj_stat != 0) {
1200                 DEBUG(1, ("NO session key for this mech\n"));
1201                 return NT_STATUS_NO_USER_SESSION_KEY;
1202         }
1203
1204         DEBUG(10, ("Got KRB5 session key of length %d%s\n",
1205                    (int)KRB5_KEY_LENGTH(subkey),
1206                    (gensec_gssapi_state->sasl_state == STAGE_DONE)?" (done)":""));
1207         *session_key = data_blob_talloc(gensec_gssapi_state,
1208                                         KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
1209         krb5_free_keyblock(gensec_gssapi_state->smb_krb5_context->krb5_context, subkey);
1210         gensec_gssapi_state->session_key = *session_key;
1211         dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
1212
1213         return NT_STATUS_OK;
1214 }
1215
1216 /* Get some basic (and authorization) information about the user on
1217  * this session.  This uses either the PAC (if present) or a local
1218  * database lookup */
1219 static NTSTATUS gensec_gssapi_session_info(struct gensec_security *gensec_security,
1220                                            struct auth_session_info **_session_info)
1221 {
1222         NTSTATUS nt_status;
1223         TALLOC_CTX *mem_ctx;
1224         struct gensec_gssapi_state *gensec_gssapi_state
1225                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1226         struct auth_serversupplied_info *server_info = NULL;
1227         struct auth_session_info *session_info = NULL;
1228         OM_uint32 maj_stat, min_stat;
1229         gss_buffer_desc pac;
1230         DATA_BLOB pac_blob;
1231
1232         if ((gensec_gssapi_state->gss_oid->length != gss_mech_krb5->length)
1233             || (memcmp(gensec_gssapi_state->gss_oid->elements, gss_mech_krb5->elements,
1234                        gensec_gssapi_state->gss_oid->length) != 0)) {
1235                 DEBUG(1, ("NO session info available for this mech\n"));
1236                 return NT_STATUS_INVALID_PARAMETER;
1237         }
1238
1239         mem_ctx = talloc_named(gensec_gssapi_state, 0, "gensec_gssapi_session_info context");
1240         NT_STATUS_HAVE_NO_MEMORY(mem_ctx);
1241
1242         maj_stat = gsskrb5_extract_authz_data_from_sec_context(&min_stat,
1243                                                                gensec_gssapi_state->gssapi_context,
1244                                                                KRB5_AUTHDATA_WIN2K_PAC,
1245                                                                &pac);
1246
1247
1248         if (maj_stat == 0) {
1249                 pac_blob = data_blob_talloc(mem_ctx, pac.value, pac.length);
1250                 gss_release_buffer(&min_stat, &pac);
1251
1252         } else {
1253                 pac_blob = data_blob(NULL, 0);
1254         }
1255
1256         /* IF we have the PAC - otherwise we need to get this
1257          * data from elsewere - local ldb, or (TODO) lookup of some
1258          * kind...
1259          */
1260         if (pac_blob.length) {
1261                 nt_status = kerberos_pac_blob_to_server_info(mem_ctx,
1262                                                              gensec_security->settings->iconv_convenience,
1263                                                              pac_blob,
1264                                                              gensec_gssapi_state->smb_krb5_context->krb5_context,
1265                                                              &server_info);
1266                 if (!NT_STATUS_IS_OK(nt_status)) {
1267                         talloc_free(mem_ctx);
1268                         return nt_status;
1269                 }
1270         } else {
1271                 gss_buffer_desc name_token;
1272                 char *principal_string;
1273
1274                 maj_stat = gss_display_name (&min_stat,
1275                                              gensec_gssapi_state->client_name,
1276                                              &name_token,
1277                                              NULL);
1278                 if (GSS_ERROR(maj_stat)) {
1279                         DEBUG(1, ("GSS display_name 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                 principal_string = talloc_strndup(mem_ctx,
1286                                                   (const char *)name_token.value,
1287                                                   name_token.length);
1288
1289                 gss_release_buffer(&min_stat, &name_token);
1290
1291                 if (!principal_string) {
1292                         talloc_free(mem_ctx);
1293                         return NT_STATUS_NO_MEMORY;
1294                 }
1295
1296                 if (gensec_security->auth_context &&
1297                     !gensec_setting_bool(gensec_security->settings, "gensec", "require_pac", false)) {
1298                         DEBUG(1, ("Unable to find PAC, resorting to local user lookup: %s\n",
1299                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1300                         nt_status = gensec_security->auth_context->get_server_info_principal(mem_ctx,
1301                                                                                              gensec_security->auth_context,
1302                                                                                              principal_string,
1303                                                                                              &server_info);
1304
1305                         if (!NT_STATUS_IS_OK(nt_status)) {
1306                                 talloc_free(mem_ctx);
1307                                 return nt_status;
1308                         }
1309                 } else {
1310                         DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access: %s\n",
1311                                   principal_string,
1312                                   gssapi_error_string(mem_ctx, maj_stat, min_stat, gensec_gssapi_state->gss_oid)));
1313                         return NT_STATUS_ACCESS_DENIED;
1314                 }
1315         }
1316
1317         /* references the server_info into the session_info */
1318         nt_status = auth_generate_session_info(mem_ctx, gensec_security->event_ctx,
1319                                                gensec_security->settings->lp_ctx, server_info, &session_info);
1320         if (!NT_STATUS_IS_OK(nt_status)) {
1321                 talloc_free(mem_ctx);
1322                 return nt_status;
1323         }
1324
1325         nt_status = gensec_gssapi_session_key(gensec_security, &session_info->session_key);
1326         if (!NT_STATUS_IS_OK(nt_status)) {
1327                 talloc_free(mem_ctx);
1328                 return nt_status;
1329         }
1330
1331         if (!(gensec_gssapi_state->got_flags & GSS_C_DELEG_FLAG)) {
1332                 DEBUG(10, ("gensec_gssapi: NO delegated credentials supplied by client\n"));
1333         } else {
1334                 krb5_error_code ret;
1335                 DEBUG(10, ("gensec_gssapi: delegated credentials supplied by client\n"));
1336                 session_info->credentials = cli_credentials_init(session_info);
1337                 if (!session_info->credentials) {
1338                         talloc_free(mem_ctx);
1339                         return NT_STATUS_NO_MEMORY;
1340                 }
1341
1342                 cli_credentials_set_conf(session_info->credentials, gensec_security->settings->lp_ctx);
1343                 /* Just so we don't segfault trying to get at a username */
1344                 cli_credentials_set_anonymous(session_info->credentials);
1345
1346                 ret = cli_credentials_set_client_gss_creds(session_info->credentials,
1347                                                            gensec_security->event_ctx,
1348                                                            gensec_security->settings->lp_ctx,
1349                                                            gensec_gssapi_state->delegated_cred_handle,
1350                                                            CRED_SPECIFIED);
1351                 if (ret) {
1352                         talloc_free(mem_ctx);
1353                         return NT_STATUS_NO_MEMORY;
1354                 }
1355
1356                 /* This credential handle isn't useful for password authentication, so ensure nobody tries to do that */
1357                 cli_credentials_set_kerberos_state(session_info->credentials, CRED_MUST_USE_KERBEROS);
1358
1359                 /* It has been taken from this place... */
1360                 gensec_gssapi_state->delegated_cred_handle = GSS_C_NO_CREDENTIAL;
1361         }
1362         talloc_steal(gensec_gssapi_state, session_info);
1363         talloc_free(mem_ctx);
1364         *_session_info = session_info;
1365
1366         return NT_STATUS_OK;
1367 }
1368
1369 static size_t gensec_gssapi_sig_size(struct gensec_security *gensec_security, size_t data_size)
1370 {
1371         struct gensec_gssapi_state *gensec_gssapi_state
1372                 = talloc_get_type(gensec_security->private_data, struct gensec_gssapi_state);
1373         NTSTATUS status;
1374
1375         if (gensec_gssapi_state->sig_size) {
1376                 return gensec_gssapi_state->sig_size;
1377         }
1378
1379         if (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG) {
1380                 gensec_gssapi_state->sig_size = 45;
1381         } else {
1382                 gensec_gssapi_state->sig_size = 37;
1383         }
1384
1385         status = gensec_gssapi_init_lucid(gensec_gssapi_state);
1386         if (!NT_STATUS_IS_OK(status)) {
1387                 return gensec_gssapi_state->sig_size;
1388         }
1389
1390         if (gensec_gssapi_state->lucid->protocol == 1) {
1391                 if (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG) {
1392                         /*
1393                          * TODO: windows uses 76 here, but we don't know
1394                          *       gss_wrap works with aes keys yet
1395                          */
1396                         gensec_gssapi_state->sig_size = 76;
1397                 } else {
1398                         gensec_gssapi_state->sig_size = 28;
1399                 }
1400         } else if (gensec_gssapi_state->lucid->protocol == 0) {
1401                 switch (gensec_gssapi_state->lucid->rfc1964_kd.ctx_key.type) {
1402                 case KEYTYPE_DES:
1403                 case KEYTYPE_ARCFOUR:
1404                 case KEYTYPE_ARCFOUR_56:
1405                         if (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG) {
1406                                 gensec_gssapi_state->sig_size = 45;
1407                         } else {
1408                                 gensec_gssapi_state->sig_size = 37;
1409                         }
1410                         break;
1411                 case KEYTYPE_DES3:
1412                         if (gensec_gssapi_state->got_flags & GSS_C_CONF_FLAG) {
1413                                 gensec_gssapi_state->sig_size = 57;
1414                         } else {
1415                                 gensec_gssapi_state->sig_size = 49;
1416                         }
1417                         break;
1418                 }
1419         }
1420
1421         return gensec_gssapi_state->sig_size;
1422 }
1423
1424 static const char *gensec_gssapi_krb5_oids[] = {
1425         GENSEC_OID_KERBEROS5_OLD,
1426         GENSEC_OID_KERBEROS5,
1427         NULL
1428 };
1429
1430 static const char *gensec_gssapi_spnego_oids[] = {
1431         GENSEC_OID_SPNEGO,
1432         NULL
1433 };
1434
1435 /* As a server, this could in theory accept any GSSAPI mech */
1436 static const struct gensec_security_ops gensec_gssapi_spnego_security_ops = {
1437         .name           = "gssapi_spnego",
1438         .sasl_name      = "GSS-SPNEGO",
1439         .auth_type      = DCERPC_AUTH_TYPE_SPNEGO,
1440         .oid            = gensec_gssapi_spnego_oids,
1441         .client_start   = gensec_gssapi_client_start,
1442         .server_start   = gensec_gssapi_server_start,
1443         .magic          = gensec_gssapi_magic,
1444         .update         = gensec_gssapi_update,
1445         .session_key    = gensec_gssapi_session_key,
1446         .session_info   = gensec_gssapi_session_info,
1447         .sign_packet    = gensec_gssapi_sign_packet,
1448         .check_packet   = gensec_gssapi_check_packet,
1449         .seal_packet    = gensec_gssapi_seal_packet,
1450         .unseal_packet  = gensec_gssapi_unseal_packet,
1451         .wrap           = gensec_gssapi_wrap,
1452         .unwrap         = gensec_gssapi_unwrap,
1453         .have_feature   = gensec_gssapi_have_feature,
1454         .enabled        = false,
1455         .kerberos       = true,
1456         .priority       = GENSEC_GSSAPI
1457 };
1458
1459 /* As a server, this could in theory accept any GSSAPI mech */
1460 static const struct gensec_security_ops gensec_gssapi_krb5_security_ops = {
1461         .name           = "gssapi_krb5",
1462         .auth_type      = DCERPC_AUTH_TYPE_KRB5,
1463         .oid            = gensec_gssapi_krb5_oids,
1464         .client_start   = gensec_gssapi_client_start,
1465         .server_start   = gensec_gssapi_server_start,
1466         .magic          = gensec_gssapi_magic,
1467         .update         = gensec_gssapi_update,
1468         .session_key    = gensec_gssapi_session_key,
1469         .session_info   = gensec_gssapi_session_info,
1470         .sig_size       = gensec_gssapi_sig_size,
1471         .sign_packet    = gensec_gssapi_sign_packet,
1472         .check_packet   = gensec_gssapi_check_packet,
1473         .seal_packet    = gensec_gssapi_seal_packet,
1474         .unseal_packet  = gensec_gssapi_unseal_packet,
1475         .wrap           = gensec_gssapi_wrap,
1476         .unwrap         = gensec_gssapi_unwrap,
1477         .have_feature   = gensec_gssapi_have_feature,
1478         .enabled        = true,
1479         .kerberos       = true,
1480         .priority       = GENSEC_GSSAPI
1481 };
1482
1483 /* As a server, this could in theory accept any GSSAPI mech */
1484 static const struct gensec_security_ops gensec_gssapi_sasl_krb5_security_ops = {
1485         .name             = "gssapi_krb5_sasl",
1486         .sasl_name        = "GSSAPI",
1487         .client_start     = gensec_gssapi_sasl_client_start,
1488         .server_start     = gensec_gssapi_sasl_server_start,
1489         .update           = gensec_gssapi_update,
1490         .session_key      = gensec_gssapi_session_key,
1491         .session_info     = gensec_gssapi_session_info,
1492         .max_input_size   = gensec_gssapi_max_input_size,
1493         .max_wrapped_size = gensec_gssapi_max_wrapped_size,
1494         .wrap             = gensec_gssapi_wrap,
1495         .unwrap           = gensec_gssapi_unwrap,
1496         .have_feature     = gensec_gssapi_have_feature,
1497         .enabled          = true,
1498         .kerberos         = true,
1499         .priority         = GENSEC_GSSAPI
1500 };
1501
1502 _PUBLIC_ NTSTATUS gensec_gssapi_init(void)
1503 {
1504         NTSTATUS ret;
1505
1506         ret = gensec_register(&gensec_gssapi_spnego_security_ops);
1507         if (!NT_STATUS_IS_OK(ret)) {
1508                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1509                         gensec_gssapi_spnego_security_ops.name));
1510                 return ret;
1511         }
1512
1513         ret = gensec_register(&gensec_gssapi_krb5_security_ops);
1514         if (!NT_STATUS_IS_OK(ret)) {
1515                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1516                         gensec_gssapi_krb5_security_ops.name));
1517                 return ret;
1518         }
1519
1520         ret = gensec_register(&gensec_gssapi_sasl_krb5_security_ops);
1521         if (!NT_STATUS_IS_OK(ret)) {
1522                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
1523                         gensec_gssapi_sasl_krb5_security_ops.name));
1524                 return ret;
1525         }
1526
1527         return ret;
1528 }