source/passdb/machine_sid.c

   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 2 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, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22 */
  23
  24 #include "includes.h"
  25
  26 /* NOTE! the global_sam_sid is the SID of our local SAM. This is only
  27    equal to the domain SID when we are a DC, otherwise its our
  28    workstation SID */
  29 static DOM_SID *global_sam_sid=NULL;
  30
  31 #undef DBGC_CLASS
  32 #define DBGC_CLASS DBGC_PASSDB
  33
  34 /****************************************************************************
  35  Read a SID from a file. This is for compatibility with the old MACHINE.SID
  36  style of SID storage
  37 ****************************************************************************/
  38 static BOOL read_sid_from_file(const char *fname, DOM_SID *sid)
  39 {
  40         char **lines;
  41         int numlines;
  42         BOOL ret;
  43
  44         lines = file_lines_load(fname, &numlines);
  45
  46         if (!lines || numlines < 1) {
  47                 if (lines) file_lines_free(lines);
  48                 return False;
  49         }
  50
  51         ret = string_to_sid(sid, lines[0]);
  52         file_lines_free(lines);
  53         return ret;
  54 }
  55
  56 /*
  57   generate a random sid - used to build our own sid if we don't have one
  58 */
  59 static void generate_random_sid(DOM_SID *sid)
  60 {
  61         int i;
  62         uchar raw_sid_data[12];
  63
  64         memset((char *)sid, '\0', sizeof(*sid));
  65         sid->sid_rev_num = 1;
  66         sid->id_auth[5] = 5;
  67         sid->num_auths = 0;
  68         sid->sub_auths[sid->num_auths++] = 21;
  69
  70         generate_random_buffer(raw_sid_data, 12);
  71         for (i = 0; i < 3; i++)
  72                 sid->sub_auths[sid->num_auths++] = IVAL(raw_sid_data, i*4);
  73 }
  74
  75 /****************************************************************************
  76  Generate the global machine sid.
  77 ****************************************************************************/
  78
  79 static DOM_SID *pdb_generate_sam_sid(void)
  80 {
  81         DOM_SID domain_sid;
  82         char *fname = NULL;
  83         BOOL is_dc = False;
  84         DOM_SID *sam_sid;
  85
  86         if(!(sam_sid=SMB_MALLOC_P(DOM_SID)))
  87                 return NULL;
  88
  89         switch (lp_server_role()) {
  90         case ROLE_DOMAIN_PDC:
  91         case ROLE_DOMAIN_BDC:
  92                 is_dc = True;
  93                 break;
  94         default:
  95                 is_dc = False;
  96                 break;
  97         }
  98
  99         if (is_dc) {
 100                 if (secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
 101                         sid_copy(sam_sid, &domain_sid);
 102                         return sam_sid;
 103                 }
 104         }
 105
 106         if (secrets_fetch_domain_sid(global_myname(), sam_sid)) {
 107
 108                 /* We got our sid. If not a pdc/bdc, we're done. */
 109                 if (!is_dc)
 110                         return sam_sid;
 111
 112                 if (!secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
 113
 114                         /* No domain sid and we're a pdc/bdc. Store it */
 115
 116                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 117                                 DEBUG(0,("pdb_generate_sam_sid: Can't store domain SID as a pdc/bdc.\n"));
 118                                 SAFE_FREE(sam_sid);
 119                                 return NULL;
 120                         }
 121                         return sam_sid;
 122                 }
 123
 124                 if (!sid_equal(&domain_sid, sam_sid)) {
 125
 126                         /* Domain name sid doesn't match global sam sid. Re-store domain sid as 'local' sid. */
 127
 128                         DEBUG(0,("pdb_generate_sam_sid: Mismatched SIDs as a pdc/bdc.\n"));
 129                         if (!secrets_store_domain_sid(global_myname(), &domain_sid)) {
 130                                 DEBUG(0,("pdb_generate_sam_sid: Can't re-store domain SID for local sid as PDC/BDC.\n"));
 131                                 SAFE_FREE(sam_sid);
 132                                 return NULL;
 133                         }
 134                         return sam_sid;
 135                 }
 136
 137                 return sam_sid;
 138
 139         }
 140
 141         /* check for an old MACHINE.SID file for backwards compatibility */
 142         asprintf(&fname, "%s/MACHINE.SID", lp_private_dir());
 143
 144         if (read_sid_from_file(fname, sam_sid)) {
 145                 /* remember it for future reference and unlink the old MACHINE.SID */
 146                 if (!secrets_store_domain_sid(global_myname(), sam_sid)) {
 147                         DEBUG(0,("pdb_generate_sam_sid: Failed to store SID from file.\n"));
 148                         SAFE_FREE(fname);
 149                         SAFE_FREE(sam_sid);
 150                         return NULL;
 151                 }
 152                 unlink(fname);
 153                 if (is_dc) {
 154                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 155                                 DEBUG(0,("pdb_generate_sam_sid: Failed to store domain SID from file.\n"));
 156                                 SAFE_FREE(fname);
 157                                 SAFE_FREE(sam_sid);
 158                                 return NULL;
 159                         }
 160                 }
 161
 162                 /* Stored the old sid from MACHINE.SID successfully.*/
 163                 SAFE_FREE(fname);
 164                 return sam_sid;
 165         }
 166
 167         SAFE_FREE(fname);
 168
 169         /* we don't have the SID in secrets.tdb, we will need to
 170            generate one and save it */
 171         generate_random_sid(sam_sid);
 172
 173         if (!secrets_store_domain_sid(global_myname(), sam_sid)) {
 174                 DEBUG(0,("pdb_generate_sam_sid: Failed to store generated machine SID.\n"));
 175                 SAFE_FREE(sam_sid);
 176                 return NULL;
 177         }
 178         if (is_dc) {
 179                 if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 180                         DEBUG(0,("pdb_generate_sam_sid: Failed to store generated domain SID.\n"));
 181                         SAFE_FREE(sam_sid);
 182                         return NULL;
 183                 }
 184         }
 185
 186         return sam_sid;
 187 }
 188
 189 /* return our global_sam_sid */
 190 DOM_SID *get_global_sam_sid(void)
 191 {
 192         if (global_sam_sid != NULL)
 193                 return global_sam_sid;
 194
 195         /* memory for global_sam_sid is allocated in
 196            pdb_generate_sam_sid() as needed */
 197
 198         if (!(global_sam_sid = pdb_generate_sam_sid())) {
 199                 smb_panic("Could not generate a machine SID\n");
 200         }
 201
 202         return global_sam_sid;
 203 }
 204
 205 /**
 206  * Force get_global_sam_sid to requery the backends
 207  */
 208 void reset_global_sam_sid(void)
 209 {
 210         SAFE_FREE(global_sam_sid);
 211 }