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 "lib/util/util_file.h"
      25             : #include "passdb/machine_sid.h"
      26             : #include "secrets.h"
      27             : #include "dbwrap/dbwrap.h"
      28             : #include "../libcli/security/security.h"
      29             : 
      30             : /* NOTE! the global_sam_sid is the SID of our local SAM. This is only
      31             :    equal to the domain SID when we are a DC, otherwise its our
      32             :    workstation SID */
      33             : static struct dom_sid *global_sam_sid=NULL;
      34             : 
      35             : #undef DBGC_CLASS
      36             : #define DBGC_CLASS DBGC_PASSDB
      37             : 
      38             : /****************************************************************************
      39             :  Read a SID from a file. This is for compatibility with the old MACHINE.SID
      40             :  style of SID storage
      41             : ****************************************************************************/
      42             : 
      43          20 : static bool read_sid_from_file(const char *fname, struct dom_sid *sid)
      44             : {
      45           2 :         char **lines;
      46           2 :         int numlines;
      47           2 :         bool ret;
      48             : 
      49          20 :         lines = file_lines_load(fname, &numlines,0, NULL);
      50             : 
      51          20 :         if (!lines || numlines < 1) {
      52          20 :                 TALLOC_FREE(lines);
      53          20 :                 return False;
      54             :         }
      55             : 
      56           0 :         ret = string_to_sid(sid, lines[0]);
      57           0 :         TALLOC_FREE(lines);
      58           0 :         return ret;
      59             : }
      60             : 
      61             : /*
      62             :   generate a random sid - used to build our own sid if we don't have one
      63             : */
      64          20 : static void generate_random_sid(struct dom_sid *sid)
      65             : {
      66           2 :         int i;
      67           2 :         uchar raw_sid_data[12];
      68             : 
      69          20 :         *sid = (struct dom_sid) {
      70             :                 .sid_rev_num = 1,
      71             :                 .id_auth[5] = 5,
      72             :         };
      73             : 
      74          20 :         sid->sub_auths[sid->num_auths++] = 21;
      75             : 
      76          20 :         generate_random_buffer(raw_sid_data, 12);
      77          82 :         for (i = 0; i < 3; i++)
      78          60 :                 sid->sub_auths[sid->num_auths++] = IVAL(raw_sid_data, i*4);
      79          20 : }
      80             : 
      81             : /****************************************************************************
      82             :  Generate the global machine sid.
      83             : ****************************************************************************/
      84             : 
      85        1668 : static struct dom_sid *pdb_generate_sam_sid(void)
      86             : {
      87          17 :         struct dom_sid domain_sid;
      88        1668 :         char *fname = NULL;
      89          17 :         struct dom_sid *sam_sid;
      90             : 
      91        1668 :         if(!(sam_sid=SMB_MALLOC_P(struct dom_sid)))
      92           0 :                 return NULL;
      93             : 
      94        1668 :         if ( IS_DC ) {
      95         816 :                 if (secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
      96         801 :                         sid_copy(sam_sid, &domain_sid);
      97         801 :                         return sam_sid;
      98             :                 }
      99             :         }
     100             : 
     101         867 :         if (secrets_fetch_domain_sid(lp_netbios_name(), sam_sid)) {
     102             : 
     103             :                 /* We got our sid. If not a pdc/bdc, we're done. */
     104         847 :                 if ( !IS_DC )
     105         830 :                         return sam_sid;
     106             : 
     107          15 :                 if (!secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
     108             : 
     109             :                         /* No domain sid and we're a pdc/bdc. Store it */
     110             : 
     111          15 :                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
     112           0 :                                 DEBUG(0,("pdb_generate_sam_sid: Can't store domain SID as a pdc/bdc.\n"));
     113           0 :                                 SAFE_FREE(sam_sid);
     114           0 :                                 return NULL;
     115             :                         }
     116          14 :                         return sam_sid;
     117             :                 }
     118             : 
     119           0 :                 if (!dom_sid_equal(&domain_sid, sam_sid)) {
     120             : 
     121             :                         /* Domain name sid doesn't match global sam sid. Re-store domain sid as 'local' sid. */
     122             : 
     123           0 :                         DEBUG(0,("pdb_generate_sam_sid: Mismatched SIDs as a pdc/bdc.\n"));
     124           0 :                         if (!secrets_store_domain_sid(lp_netbios_name(), &domain_sid)) {
     125           0 :                                 DEBUG(0,("pdb_generate_sam_sid: Can't re-store domain SID for local sid as PDC/BDC.\n"));
     126           0 :                                 SAFE_FREE(sam_sid);
     127           0 :                                 return NULL;
     128             :                         }
     129           0 :                         return sam_sid;
     130             :                 }
     131             : 
     132           0 :                 return sam_sid;
     133             :         }
     134             : 
     135             :         /* check for an old MACHINE.SID file for backwards compatibility */
     136          20 :         if (asprintf(&fname, "%s/MACHINE.SID", lp_private_dir()) == -1) {
     137           0 :                 SAFE_FREE(sam_sid);
     138           0 :                 return NULL;
     139             :         }
     140             : 
     141          20 :         if (read_sid_from_file(fname, sam_sid)) {
     142             :                 /* remember it for future reference and unlink the old MACHINE.SID */
     143           0 :                 if (!secrets_store_domain_sid(lp_netbios_name(), sam_sid)) {
     144           0 :                         DEBUG(0,("pdb_generate_sam_sid: Failed to store SID from file.\n"));
     145           0 :                         SAFE_FREE(fname);
     146           0 :                         SAFE_FREE(sam_sid);
     147           0 :                         return NULL;
     148             :                 }
     149           0 :                 unlink(fname);
     150           0 :                 if ( !IS_DC ) {
     151           0 :                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
     152           0 :                                 DEBUG(0,("pdb_generate_sam_sid: Failed to store domain SID from file.\n"));
     153           0 :                                 SAFE_FREE(fname);
     154           0 :                                 SAFE_FREE(sam_sid);
     155           0 :                                 return NULL;
     156             :                         }
     157             :                 }
     158             : 
     159             :                 /* Stored the old sid from MACHINE.SID successfully.*/
     160           0 :                 SAFE_FREE(fname);
     161           0 :                 return sam_sid;
     162             :         }
     163             : 
     164          20 :         SAFE_FREE(fname);
     165             : 
     166             :         /* we don't have the SID in secrets.tdb, we will need to
     167             :            generate one and save it */
     168          20 :         generate_random_sid(sam_sid);
     169             : 
     170          20 :         if (!secrets_store_domain_sid(lp_netbios_name(), sam_sid)) {
     171           0 :                 DEBUG(0,("pdb_generate_sam_sid: Failed to store generated machine SID.\n"));
     172           0 :                 SAFE_FREE(sam_sid);
     173           0 :                 return NULL;
     174             :         }
     175          20 :         if ( IS_DC ) {
     176           0 :                 if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
     177           0 :                         DEBUG(0,("pdb_generate_sam_sid: Failed to store generated domain SID.\n"));
     178           0 :                         SAFE_FREE(sam_sid);
     179           0 :                         return NULL;
     180             :                 }
     181             :         }
     182             : 
     183          18 :         return sam_sid;
     184             : }
     185             : 
     186             : /* return our global_sam_sid */
     187      653123 : struct dom_sid *get_global_sam_sid(void)
     188             : {
     189        1536 :         struct db_context *db;
     190             : 
     191      653123 :         if (global_sam_sid != NULL)
     192      649936 :                 return global_sam_sid;
     193             : 
     194             :         /*
     195             :          * memory for global_sam_sid is allocated in
     196             :          * pdb_generate_sam_sid() as needed
     197             :          *
     198             :          * Note: this is guarded by a transaction
     199             :          *       to prevent races on startup which
     200             :          *       can happen with some dbwrap backends
     201             :          */
     202             : 
     203        1668 :         db = secrets_db_ctx();
     204        1668 :         if (!db) {
     205           0 :                 smb_panic("could not open secrets db");
     206             :         }
     207             : 
     208        1668 :         if (dbwrap_transaction_start(db) != 0) {
     209           0 :                 smb_panic("could not start transaction on secrets db");
     210             :         }
     211             : 
     212        1668 :         if (!(global_sam_sid = pdb_generate_sam_sid())) {
     213           0 :                 dbwrap_transaction_cancel(db);
     214           0 :                 smb_panic("could not generate a machine SID");
     215             :         }
     216             : 
     217        1668 :         if (dbwrap_transaction_commit(db) != 0) {
     218           0 :                 smb_panic("could not start commit secrets db");
     219             :         }
     220             : 
     221        1668 :         return global_sam_sid;
     222             : }
     223             : 
     224             : /**
     225             :  * Force get_global_sam_sid to requery the backends
     226             :  */
     227         487 : void reset_global_sam_sid(void) 
     228             : {
     229         487 :         SAFE_FREE(global_sam_sid);
     230         487 : }
     231             : 
     232             : /*****************************************************************
     233             :  Check if the SID is our sam SID (S-1-5-21-x-y-z).
     234             : *****************************************************************/
     235             : 
     236      191585 : bool sid_check_is_our_sam(const struct dom_sid *sid)
     237             : {
     238      191585 :         return dom_sid_equal(sid, get_global_sam_sid());
     239             : }
     240             : 
     241             : /*****************************************************************
     242             :  Check if the SID is our domain SID (S-1-5-21-x-y-z).
     243             : *****************************************************************/
     244             : 
     245      125864 : bool sid_check_is_in_our_sam(const struct dom_sid *sid)
     246             : {
     247         325 :         struct dom_sid dom_sid;
     248             : 
     249      125864 :         sid_copy(&dom_sid, sid);
     250      125864 :         sid_split_rid(&dom_sid, NULL);
     251      125864 :         return sid_check_is_our_sam(&dom_sid);
     252             : }