Line data    Source code

       1             : /*
       2             :    Unix SMB/CIFS implementation.
       3             :    Password and authentication handling
       4             :    Copyright (C) Jeremy Allison                 1996-2002
       5             :    Copyright (C) Andrew Tridgell                2002
       6             :    Copyright (C) Gerald (Jerry) Carter          2000
       7             :    Copyright (C) Stefan (metze) Metzmacher      2002
       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             :    You should have received a copy of the GNU General Public License
      20             :    along with this program.  If not, see <http://www.gnu.org/licenses/>.
      21             : */
      22             : 
      23             : #include "includes.h"
      24             : #include "passdb/machine_sid.h"
      25             : #include "secrets.h"
      26             : #include "dbwrap/dbwrap.h"
      27             : #include "../libcli/security/security.h"
      28             : 
      29             : /* NOTE! the global_sam_sid is the SID of our local SAM. This is only
      30             :    equal to the domain SID when we are a DC, otherwise its our
      31             :    workstation SID */
      32             : static struct dom_sid *global_sam_sid=NULL;
      33             : 
      34             : #undef DBGC_CLASS
      35             : #define DBGC_CLASS DBGC_PASSDB
      36             : 
      37             : /****************************************************************************
      38             :  Read a SID from a file. This is for compatibility with the old MACHINE.SID
      39             :  style of SID storage
      40             : ****************************************************************************/
      41             : 
      42         140 : static bool read_sid_from_file(const char *fname, struct dom_sid *sid)
      43             : {
      44          16 :         char **lines;
      45          16 :         int numlines;
      46          16 :         bool ret;
      47             : 
      48         140 :         lines = file_lines_load(fname, &numlines,0, NULL);
      49             : 
      50         140 :         if (!lines || numlines < 1) {
      51         140 :                 TALLOC_FREE(lines);
      52         140 :                 return False;
      53             :         }
      54             : 
      55           0 :         ret = string_to_sid(sid, lines[0]);
      56           0 :         TALLOC_FREE(lines);
      57           0 :         return ret;
      58             : }
      59             : 
      60             : /*
      61             :   generate a random sid - used to build our own sid if we don't have one
      62             : */
      63         140 : static void generate_random_sid(struct dom_sid *sid)
      64             : {
      65          16 :         int i;
      66          16 :         uchar raw_sid_data[12];
      67             : 
      68         140 :         *sid = (struct dom_sid) {
      69             :                 .sid_rev_num = 1,
      70             :                 .id_auth[5] = 5,
      71             :         };
      72             : 
      73         140 :         sid->sub_auths[sid->num_auths++] = 21;
      74             : 
      75         140 :         generate_random_buffer(raw_sid_data, 12);
      76         576 :         for (i = 0; i < 3; i++)
      77         420 :                 sid->sub_auths[sid->num_auths++] = IVAL(raw_sid_data, i*4);
      78         140 : }
      79             : 
      80             : /****************************************************************************
      81             :  Generate the global machine sid.
      82             : ****************************************************************************/
      83             : 
      84        2051 : static struct dom_sid *pdb_generate_sam_sid(void)
      85             : {
      86          50 :         struct dom_sid domain_sid;
      87        2051 :         char *fname = NULL;
      88          50 :         struct dom_sid *sam_sid;
      89             : 
      90        2051 :         if(!(sam_sid=SMB_MALLOC_P(struct dom_sid)))
      91           0 :                 return NULL;
      92             : 
      93        2051 :         if ( IS_DC ) {
      94         768 :                 if (secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
      95         757 :                         sid_copy(sam_sid, &domain_sid);
      96         757 :                         return sam_sid;
      97             :                 }
      98             :         }
      99             : 
     100        1294 :         if (secrets_fetch_domain_sid(lp_netbios_name(), sam_sid)) {
     101             : 
     102             :                 /* We got our sid. If not a pdc/bdc, we're done. */
     103        1154 :                 if ( !IS_DC )
     104        1121 :                         return sam_sid;
     105             : 
     106          11 :                 if (!secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
     107             : 
     108             :                         /* No domain sid and we're a pdc/bdc. Store it */
     109             : 
     110          11 :                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
     111           0 :                                 DEBUG(0,("pdb_generate_sam_sid: Can't store domain SID as a pdc/bdc.\n"));
     112           0 :                                 SAFE_FREE(sam_sid);
     113           0 :                                 return NULL;
     114             :                         }
     115          10 :                         return sam_sid;
     116             :                 }
     117             : 
     118           0 :                 if (!dom_sid_equal(&domain_sid, sam_sid)) {
     119             : 
     120             :                         /* Domain name sid doesn't match global sam sid. Re-store domain sid as 'local' sid. */
     121             : 
     122           0 :                         DEBUG(0,("pdb_generate_sam_sid: Mismatched SIDs as a pdc/bdc.\n"));
     123           0 :                         if (!secrets_store_domain_sid(lp_netbios_name(), &domain_sid)) {
     124           0 :                                 DEBUG(0,("pdb_generate_sam_sid: Can't re-store domain SID for local sid as PDC/BDC.\n"));
     125           0 :                                 SAFE_FREE(sam_sid);
     126           0 :                                 return NULL;
     127             :                         }
     128           0 :                         return sam_sid;
     129             :                 }
     130             : 
     131           0 :                 return sam_sid;
     132             :         }
     133             : 
     134             :         /* check for an old MACHINE.SID file for backwards compatibility */
     135         140 :         if (asprintf(&fname, "%s/MACHINE.SID", lp_private_dir()) == -1) {
     136           0 :                 SAFE_FREE(sam_sid);
     137           0 :                 return NULL;
     138             :         }
     139             : 
     140         140 :         if (read_sid_from_file(fname, sam_sid)) {
     141             :                 /* remember it for future reference and unlink the old MACHINE.SID */
     142           0 :                 if (!secrets_store_domain_sid(lp_netbios_name(), sam_sid)) {
     143           0 :                         DEBUG(0,("pdb_generate_sam_sid: Failed to store SID from file.\n"));
     144           0 :                         SAFE_FREE(fname);
     145           0 :                         SAFE_FREE(sam_sid);
     146           0 :                         return NULL;
     147             :                 }
     148           0 :                 unlink(fname);
     149           0 :                 if ( !IS_DC ) {
     150           0 :                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
     151           0 :                                 DEBUG(0,("pdb_generate_sam_sid: Failed to store domain SID from file.\n"));
     152           0 :                                 SAFE_FREE(fname);
     153           0 :                                 SAFE_FREE(sam_sid);
     154           0 :                                 return NULL;
     155             :                         }
     156             :                 }
     157             : 
     158             :                 /* Stored the old sid from MACHINE.SID successfully.*/
     159           0 :                 SAFE_FREE(fname);
     160           0 :                 return sam_sid;
     161             :         }
     162             : 
     163         140 :         SAFE_FREE(fname);
     164             : 
     165             :         /* we don't have the SID in secrets.tdb, we will need to
     166             :            generate one and save it */
     167         140 :         generate_random_sid(sam_sid);
     168             : 
     169         140 :         if (!secrets_store_domain_sid(lp_netbios_name(), sam_sid)) {
     170           0 :                 DEBUG(0,("pdb_generate_sam_sid: Failed to store generated machine SID.\n"));
     171           0 :                 SAFE_FREE(sam_sid);
     172           0 :                 return NULL;
     173             :         }
     174         140 :         if ( IS_DC ) {
     175           0 :                 if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
     176           0 :                         DEBUG(0,("pdb_generate_sam_sid: Failed to store generated domain SID.\n"));
     177           0 :                         SAFE_FREE(sam_sid);
     178           0 :                         return NULL;
     179             :                 }
     180             :         }
     181             : 
     182         124 :         return sam_sid;
     183             : }
     184             : 
     185             : /* return our global_sam_sid */
     186      650912 : struct dom_sid *get_global_sam_sid(void)
     187             : {
     188        1586 :         struct db_context *db;
     189             : 
     190      650912 :         if (global_sam_sid != NULL)
     191      647325 :                 return global_sam_sid;
     192             : 
     193             :         /*
     194             :          * memory for global_sam_sid is allocated in
     195             :          * pdb_generate_sam_sid() as needed
     196             :          *
     197             :          * Note: this is guarded by a transaction
     198             :          *       to prevent races on startup which
     199             :          *       can happen with some dbwrap backends
     200             :          */
     201             : 
     202        2051 :         db = secrets_db_ctx();
     203        2051 :         if (!db) {
     204           0 :                 smb_panic("could not open secrets db");
     205             :         }
     206             : 
     207        2051 :         if (dbwrap_transaction_start(db) != 0) {
     208           0 :                 smb_panic("could not start transaction on secrets db");
     209             :         }
     210             : 
     211        2051 :         if (!(global_sam_sid = pdb_generate_sam_sid())) {
     212           0 :                 dbwrap_transaction_cancel(db);
     213           0 :                 smb_panic("could not generate a machine SID");
     214             :         }
     215             : 
     216        2051 :         if (dbwrap_transaction_commit(db) != 0) {
     217           0 :                 smb_panic("could not start commit secrets db");
     218             :         }
     219             : 
     220        2051 :         return global_sam_sid;
     221             : }
     222             : 
     223             : /**
     224             :  * Force get_global_sam_sid to requery the backends
     225             :  */
     226         269 : void reset_global_sam_sid(void) 
     227             : {
     228         269 :         SAFE_FREE(global_sam_sid);
     229         269 : }
     230             : 
     231             : /*****************************************************************
     232             :  Check if the SID is our sam SID (S-1-5-21-x-y-z).
     233             : *****************************************************************/
     234             : 
     235      191121 : bool sid_check_is_our_sam(const struct dom_sid *sid)
     236             : {
     237      191121 :         return dom_sid_equal(sid, get_global_sam_sid());
     238             : }
     239             : 
     240             : /*****************************************************************
     241             :  Check if the SID is our domain SID (S-1-5-21-x-y-z).
     242             : *****************************************************************/
     243             : 
     244      123186 : bool sid_check_is_in_our_sam(const struct dom_sid *sid)
     245             : {
     246         325 :         struct dom_sid dom_sid;
     247             : 
     248      123186 :         sid_copy(&dom_sid, sid);
     249      123186 :         sid_split_rid(&dom_sid, NULL);
     250      123186 :         return sid_check_is_our_sam(&dom_sid);
     251             : }