source3/auth/token_util.c

   1 /*
   2  *  Unix SMB/CIFS implementation.
   3  *  Authentication utility functions
   4  *  Copyright (C) Andrew Tridgell 1992-1998
   5  *  Copyright (C) Andrew Bartlett 2001
   6  *  Copyright (C) Jeremy Allison 2000-2001
   7  *  Copyright (C) Rafal Szczesniak 2002
   8  *  Copyright (C) Volker Lendecke 2006
   9  *  Copyright (C) Michael Adam 2007
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; either version 3 of the License, or
  14  *  (at your option) any later version.
  15  *
  16  *  This program is distributed in the hope that it will be useful,
  17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  *  GNU General Public License for more details.
  20  *
  21  *  You should have received a copy of the GNU General Public License
  22  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  23  */
  24
  25 /* functions moved from auth/auth_util.c to minimize linker deps */
  26
  27 #include "includes.h"
  28
  29 /****************************************************************************
  30  Check for a SID in an NT_USER_TOKEN
  31 ****************************************************************************/
  32
  33 bool nt_token_check_sid ( const DOM_SID *sid, const NT_USER_TOKEN *token )
  34 {
  35         int i;
  36
  37         if ( !sid || !token )
  38                 return False;
  39
  40         for ( i=0; i<token->num_sids; i++ ) {
  41                 if ( sid_equal( sid, &token->user_sids[i] ) )
  42                         return True;
  43         }
  44
  45         return False;
  46 }
  47
  48 bool nt_token_check_domain_rid( NT_USER_TOKEN *token, uint32 rid )
  49 {
  50         DOM_SID domain_sid;
  51
  52         /* if we are a domain member, the get the domain SID, else for
  53            a DC or standalone server, use our own SID */
  54
  55         if ( lp_server_role() == ROLE_DOMAIN_MEMBER ) {
  56                 if ( !secrets_fetch_domain_sid( lp_workgroup(),
  57                                                 &domain_sid ) ) {
  58                         DEBUG(1,("nt_token_check_domain_rid: Cannot lookup "
  59                                  "SID for domain [%s]\n", lp_workgroup()));
  60                         return False;
  61                 }
  62         }
  63         else
  64                 sid_copy( &domain_sid, get_global_sam_sid() );
  65
  66         sid_append_rid( &domain_sid, rid );
  67
  68         return nt_token_check_sid( &domain_sid, token );\
  69 }
  70
  71 /******************************************************************************
  72  Create a token for the root user to be used internally by smbd.
  73  This is similar to running under the context of the LOCAL_SYSTEM account
  74  in Windows.  This is a read-only token.  Do not modify it or free() it.
  75  Create a copy if your need to change it.
  76 ******************************************************************************/
  77
  78 NT_USER_TOKEN *get_root_nt_token( void )
  79 {
  80         struct nt_user_token *token = NULL;
  81         DOM_SID u_sid, g_sid;
  82         struct passwd *pw;
  83         void *cache_data;
  84
  85         cache_data = memcache_lookup_talloc(
  86                 NULL, SINGLETON_CACHE_TALLOC,
  87                 data_blob_string_const("root_nt_token"));
  88
  89         if (cache_data != NULL) {
  90                 return talloc_get_type_abort(
  91                         cache_data, struct nt_user_token);
  92         }
  93
  94         if ( !(pw = sys_getpwnam( "root" )) ) {
  95                 DEBUG(0,("get_root_nt_token: getpwnam(\"root\") failed!\n"));
  96                 return NULL;
  97         }
  98
  99         /* get the user and primary group SIDs; although the
 100            BUILTIN\Administrators SId is really the one that matters here */
 101
 102         uid_to_sid(&u_sid, pw->pw_uid);
 103         gid_to_sid(&g_sid, pw->pw_gid);
 104
 105         token = create_local_nt_token(NULL, &u_sid, False,
 106                                       1, &global_sid_Builtin_Administrators);
 107
 108         memcache_add_talloc(
 109                 NULL, SINGLETON_CACHE_TALLOC,
 110                 data_blob_string_const("root_nt_token"), token);
 111
 112         return token;
 113 }
 114
 115
 116 /*
 117  * Add alias SIDs from memberships within the partially created token SID list
 118  */
 119
 120 NTSTATUS add_aliases(const DOM_SID *domain_sid,
 121                      struct nt_user_token *token)
 122 {
 123         uint32 *aliases;
 124         size_t i, num_aliases;
 125         NTSTATUS status;
 126         TALLOC_CTX *tmp_ctx;
 127
 128         if (!(tmp_ctx = talloc_init("add_aliases"))) {
 129                 return NT_STATUS_NO_MEMORY;
 130         }
 131
 132         aliases = NULL;
 133         num_aliases = 0;
 134
 135         status = pdb_enum_alias_memberships(tmp_ctx, domain_sid,
 136                                             token->user_sids,
 137                                             token->num_sids,
 138                                             &aliases, &num_aliases);
 139
 140         if (!NT_STATUS_IS_OK(status)) {
 141                 DEBUG(10, ("pdb_enum_alias_memberships failed: %s\n",
 142                            nt_errstr(status)));
 143                 goto done;
 144         }
 145
 146         for (i=0; i<num_aliases; i++) {
 147                 DOM_SID alias_sid;
 148                 sid_compose(&alias_sid, domain_sid, aliases[i]);
 149                 status = add_sid_to_array_unique(token, &alias_sid,
 150                                                  &token->user_sids,
 151                                                  &token->num_sids);
 152                 if (!NT_STATUS_IS_OK(status)) {
 153                         DEBUG(0, ("add_sid_to_array failed\n"));
 154                         goto done;
 155                 }
 156         }
 157
 158 done:
 159         TALLOC_FREE(tmp_ctx);
 160         return NT_STATUS_OK;
 161 }
 162
 163 /*******************************************************************
 164 *******************************************************************/
 165
 166 static NTSTATUS add_builtin_administrators( struct nt_user_token *token )
 167 {
 168         DOM_SID domadm;
 169         NTSTATUS status;
 170
 171         /* nothing to do if we aren't in a domain */
 172
 173         if ( !(IS_DC || lp_server_role()==ROLE_DOMAIN_MEMBER) ) {
 174                 return NT_STATUS_OK;
 175         }
 176
 177         /* Find the Domain Admins SID */
 178
 179         if ( IS_DC ) {
 180                 sid_copy( &domadm, get_global_sam_sid() );
 181         } else {
 182                 if ( !secrets_fetch_domain_sid( lp_workgroup(), &domadm ) )
 183                         return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
 184         }
 185         sid_append_rid( &domadm, DOMAIN_GROUP_RID_ADMINS );
 186
 187         /* Add Administrators if the user beloongs to Domain Admins */
 188
 189         if ( nt_token_check_sid( &domadm, token ) ) {
 190                 status = add_sid_to_array(token,
 191                                           &global_sid_Builtin_Administrators,
 192                                           &token->user_sids, &token->num_sids);
 193         if (!NT_STATUS_IS_OK(status)) {
 194                         return status;
 195                 }
 196         }
 197
 198         return NT_STATUS_OK;
 199 }
 200
 201 /*******************************************************************
 202 *******************************************************************/
 203
 204 static NTSTATUS create_builtin_users( void )
 205 {
 206         NTSTATUS status;
 207         DOM_SID dom_users;
 208
 209         status = pdb_create_builtin_alias( BUILTIN_ALIAS_RID_USERS );
 210         if ( !NT_STATUS_IS_OK(status) ) {
 211                 DEBUG(0,("create_builtin_users: Failed to create Users\n"));
 212                 return status;
 213         }
 214
 215         /* add domain users */
 216         if ((IS_DC || (lp_server_role() == ROLE_DOMAIN_MEMBER))
 217                 && secrets_fetch_domain_sid(lp_workgroup(), &dom_users))
 218         {
 219                 sid_append_rid(&dom_users, DOMAIN_GROUP_RID_USERS );
 220                 status = pdb_add_aliasmem( &global_sid_Builtin_Users, &dom_users);
 221                 if ( !NT_STATUS_IS_OK(status) ) {
 222                         DEBUG(0,("create_builtin_administrators: Failed to add Domain Users to"
 223                                 " Users\n"));
 224                         return status;
 225                 }
 226         }
 227
 228         return NT_STATUS_OK;
 229 }
 230
 231 /*******************************************************************
 232 *******************************************************************/
 233
 234 static NTSTATUS create_builtin_administrators( void )
 235 {
 236         NTSTATUS status;
 237         DOM_SID dom_admins, root_sid;
 238         fstring root_name;
 239         enum lsa_SidType type;
 240         TALLOC_CTX *ctx;
 241         bool ret;
 242
 243         status = pdb_create_builtin_alias( BUILTIN_ALIAS_RID_ADMINS );
 244         if ( !NT_STATUS_IS_OK(status) ) {
 245                 DEBUG(0,("create_builtin_administrators: Failed to create Administrators\n"));
 246                 return status;
 247         }
 248
 249         /* add domain admins */
 250         if ((IS_DC || (lp_server_role() == ROLE_DOMAIN_MEMBER))
 251                 && secrets_fetch_domain_sid(lp_workgroup(), &dom_admins))
 252         {
 253                 sid_append_rid(&dom_admins, DOMAIN_GROUP_RID_ADMINS);
 254                 status = pdb_add_aliasmem( &global_sid_Builtin_Administrators, &dom_admins );
 255                 if ( !NT_STATUS_IS_OK(status) ) {
 256                         DEBUG(0,("create_builtin_administrators: Failed to add Domain Admins"
 257                                 " Administrators\n"));
 258                         return status;
 259                 }
 260         }
 261
 262         /* add root */
 263         if ( (ctx = talloc_init("create_builtin_administrators")) == NULL ) {
 264                 return NT_STATUS_NO_MEMORY;
 265         }
 266         fstr_sprintf( root_name, "%s\\root", get_global_sam_name() );
 267         ret = lookup_name(ctx, root_name, LOOKUP_NAME_DOMAIN, NULL, NULL,
 268                           &root_sid, &type);
 269         TALLOC_FREE( ctx );
 270
 271         if ( ret ) {
 272                 status = pdb_add_aliasmem( &global_sid_Builtin_Administrators, &root_sid );
 273                 if ( !NT_STATUS_IS_OK(status) ) {
 274                         DEBUG(0,("create_builtin_administrators: Failed to add root"
 275                                 " Administrators\n"));
 276                         return status;
 277                 }
 278         }
 279
 280         return NT_STATUS_OK;
 281 }
 282
 283
 284 /*******************************************************************
 285  Create a NT token for the user, expanding local aliases
 286 *******************************************************************/
 287
 288 struct nt_user_token *create_local_nt_token(TALLOC_CTX *mem_ctx,
 289                                             const DOM_SID *user_sid,
 290                                             bool is_guest,
 291                                             int num_groupsids,
 292                                             const DOM_SID *groupsids)
 293 {
 294         struct nt_user_token *result = NULL;
 295         int i;
 296         NTSTATUS status;
 297         gid_t gid;
 298
 299         DEBUG(10, ("Create local NT token for %s\n",
 300                    sid_string_dbg(user_sid)));
 301
 302         if (!(result = TALLOC_ZERO_P(mem_ctx, struct nt_user_token))) {
 303                 DEBUG(0, ("talloc failed\n"));
 304                 return NULL;
 305         }
 306
 307         /* Add the user and primary group sid */
 308
 309         status = add_sid_to_array(result, user_sid,
 310                                   &result->user_sids, &result->num_sids);
 311         if (!NT_STATUS_IS_OK(status)) {
 312                 return NULL;
 313         }
 314
 315         /* For guest, num_groupsids may be zero. */
 316         if (num_groupsids) {
 317                 status = add_sid_to_array(result, &groupsids[0],
 318                                           &result->user_sids,
 319                                           &result->num_sids);
 320                 if (!NT_STATUS_IS_OK(status)) {
 321                         return NULL;
 322                 }
 323         }
 324
 325         /* Add in BUILTIN sids */
 326
 327         status = add_sid_to_array(result, &global_sid_World,
 328                                   &result->user_sids, &result->num_sids);
 329         if (!NT_STATUS_IS_OK(status)) {
 330                 return NULL;
 331         }
 332         status = add_sid_to_array(result, &global_sid_Network,
 333                                   &result->user_sids, &result->num_sids);
 334         if (!NT_STATUS_IS_OK(status)) {
 335                 return NULL;
 336         }
 337
 338         if (is_guest) {
 339                 status = add_sid_to_array(result, &global_sid_Builtin_Guests,
 340                                           &result->user_sids,
 341                                           &result->num_sids);
 342                 if (!NT_STATUS_IS_OK(status)) {
 343                         return NULL;
 344                 }
 345         } else {
 346                 status = add_sid_to_array(result,
 347                                           &global_sid_Authenticated_Users,
 348                                           &result->user_sids,
 349                                           &result->num_sids);
 350                 if (!NT_STATUS_IS_OK(status)) {
 351                         return NULL;
 352                 }
 353         }
 354
 355         /* Now the SIDs we got from authentication. These are the ones from
 356          * the info3 struct or from the pdb_enum_group_memberships, depending
 357          * on who authenticated the user.
 358          * Note that we start the for loop at "1" here, we already added the
 359          * first group sid as primary above. */
 360
 361         for (i=1; i<num_groupsids; i++) {
 362                 status = add_sid_to_array_unique(result, &groupsids[i],
 363                                                  &result->user_sids,
 364                                                  &result->num_sids);
 365                 if (!NT_STATUS_IS_OK(status)) {
 366                         return NULL;
 367                 }
 368         }
 369
 370         /* Deal with the BUILTIN\Administrators group.  If the SID can
 371            be resolved then assume that the add_aliasmem( S-1-5-32 )
 372            handled it. */
 373
 374         if ( !sid_to_gid( &global_sid_Builtin_Administrators, &gid ) ) {
 375                 /* We can only create a mapping if winbind is running
 376                    and the nested group functionality has been enabled */
 377
 378                 if ( lp_winbind_nested_groups() && winbind_ping() ) {
 379                         become_root();
 380                         status = create_builtin_administrators( );
 381                         if ( !NT_STATUS_IS_OK(status) ) {
 382                                 DEBUG(2,("create_local_nt_token: Failed to create BUILTIN\\Administrators group!\n"));
 383                                 /* don't fail, just log the message */
 384                         }
 385                         unbecome_root();
 386                 }
 387                 else {
 388                         status = add_builtin_administrators( result );
 389                         if ( !NT_STATUS_IS_OK(status) ) {
 390                                 /* just log a complaint but do not fail */
 391                                 DEBUG(3,("create_local_nt_token: failed to check for local Administrators"
 392                                         " membership (%s)\n", nt_errstr(status)));
 393                         }
 394                 }
 395         }
 396
 397         /* Deal with the BUILTIN\Users group.  If the SID can
 398            be resolved then assume that the add_aliasmem( S-1-5-32 )
 399            handled it. */
 400
 401         if ( !sid_to_gid( &global_sid_Builtin_Users, &gid ) ) {
 402                 /* We can only create a mapping if winbind is running
 403                    and the nested group functionality has been enabled */
 404
 405                 if ( lp_winbind_nested_groups() && winbind_ping() ) {
 406                         become_root();
 407                         status = create_builtin_users( );
 408                         if ( !NT_STATUS_IS_OK(status) ) {
 409                                 DEBUG(2,("create_local_nt_token: Failed to create BUILTIN\\Users group!\n"));
 410                                 /* don't fail, just log the message */
 411                         }
 412                         unbecome_root();
 413                 }
 414         }
 415
 416         /* Deal with local groups */
 417
 418         if (lp_winbind_nested_groups()) {
 419
 420                 become_root();
 421
 422                 /* Now add the aliases. First the one from our local SAM */
 423
 424                 status = add_aliases(get_global_sam_sid(), result);
 425
 426                 if (!NT_STATUS_IS_OK(status)) {
 427                         unbecome_root();
 428                         TALLOC_FREE(result);
 429                         return NULL;
 430                 }
 431
 432                 /* Finally the builtin ones */
 433
 434                 status = add_aliases(&global_sid_Builtin, result);
 435
 436                 if (!NT_STATUS_IS_OK(status)) {
 437                         unbecome_root();
 438                         TALLOC_FREE(result);
 439                         return NULL;
 440                 }
 441
 442                 unbecome_root();
 443         }
 444
 445
 446         get_privileges_for_sids(&result->privileges, result->user_sids,
 447                                 result->num_sids);
 448         return result;
 449 }
 450
 451 /****************************************************************************
 452  prints a NT_USER_TOKEN to debug output.
 453 ****************************************************************************/
 454
 455 void debug_nt_user_token(int dbg_class, int dbg_lev, NT_USER_TOKEN *token)
 456 {
 457         size_t     i;
 458
 459         if (!token) {
 460                 DEBUGC(dbg_class, dbg_lev, ("NT user token: (NULL)\n"));
 461                 return;
 462         }
 463
 464         DEBUGC(dbg_class, dbg_lev,
 465                ("NT user token of user %s\n",
 466                 sid_string_dbg(&token->user_sids[0]) ));
 467         DEBUGADDC(dbg_class, dbg_lev,
 468                   ("contains %lu SIDs\n", (unsigned long)token->num_sids));
 469         for (i = 0; i < token->num_sids; i++)
 470                 DEBUGADDC(dbg_class, dbg_lev,
 471                           ("SID[%3lu]: %s\n", (unsigned long)i,
 472                            sid_string_dbg(&token->user_sids[i])));
 473
 474         dump_se_priv( dbg_class, dbg_lev, &token->privileges );
 475 }
 476
 477 /****************************************************************************
 478  prints a UNIX 'token' to debug output.
 479 ****************************************************************************/
 480
 481 void debug_unix_user_token(int dbg_class, int dbg_lev, uid_t uid, gid_t gid,
 482                            int n_groups, gid_t *groups)
 483 {
 484         int     i;
 485         DEBUGC(dbg_class, dbg_lev,
 486                ("UNIX token of user %ld\n", (long int)uid));
 487
 488         DEBUGADDC(dbg_class, dbg_lev,
 489                   ("Primary group is %ld and contains %i supplementary "
 490                    "groups\n", (long int)gid, n_groups));
 491         for (i = 0; i < n_groups; i++)
 492                 DEBUGADDC(dbg_class, dbg_lev, ("Group[%3i]: %ld\n", i,
 493                         (long int)groups[i]));
 494 }
 495
 496 /* END */