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         generate_wellknown_sids();
  90
  91         switch (lp_server_role()) {
  92         case ROLE_DOMAIN_PDC:
  93         case ROLE_DOMAIN_BDC:
  94                 is_dc = True;
  95                 break;
  96         default:
  97                 is_dc = False;
  98                 break;
  99         }
 100
 101         if (is_dc) {
 102                 if (secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
 103                         sid_copy(sam_sid, &domain_sid);
 104                         return sam_sid;
 105                 }
 106         }
 107
 108         if (secrets_fetch_domain_sid(global_myname(), sam_sid)) {
 109
 110                 /* We got our sid. If not a pdc/bdc, we're done. */
 111                 if (!is_dc)
 112                         return sam_sid;
 113
 114                 if (!secrets_fetch_domain_sid(lp_workgroup(), &domain_sid)) {
 115
 116                         /* No domain sid and we're a pdc/bdc. Store it */
 117
 118                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 119                                 DEBUG(0,("pdb_generate_sam_sid: Can't store domain SID as a pdc/bdc.\n"));
 120                                 SAFE_FREE(sam_sid);
 121                                 return NULL;
 122                         }
 123                         return sam_sid;
 124                 }
 125
 126                 if (!sid_equal(&domain_sid, sam_sid)) {
 127
 128                         /* Domain name sid doesn't match global sam sid. Re-store domain sid as 'local' sid. */
 129
 130                         DEBUG(0,("pdb_generate_sam_sid: Mismatched SIDs as a pdc/bdc.\n"));
 131                         if (!secrets_store_domain_sid(global_myname(), &domain_sid)) {
 132                                 DEBUG(0,("pdb_generate_sam_sid: Can't re-store domain SID for local sid as PDC/BDC.\n"));
 133                                 SAFE_FREE(sam_sid);
 134                                 return NULL;
 135                         }
 136                         return sam_sid;
 137                 }
 138
 139                 return sam_sid;
 140
 141         }
 142
 143         /* check for an old MACHINE.SID file for backwards compatibility */
 144         asprintf(&fname, "%s/MACHINE.SID", lp_private_dir());
 145
 146         if (read_sid_from_file(fname, sam_sid)) {
 147                 /* remember it for future reference and unlink the old MACHINE.SID */
 148                 if (!secrets_store_domain_sid(global_myname(), sam_sid)) {
 149                         DEBUG(0,("pdb_generate_sam_sid: Failed to store SID from file.\n"));
 150                         SAFE_FREE(fname);
 151                         SAFE_FREE(sam_sid);
 152                         return NULL;
 153                 }
 154                 unlink(fname);
 155                 if (is_dc) {
 156                         if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 157                                 DEBUG(0,("pdb_generate_sam_sid: Failed to store domain SID from file.\n"));
 158                                 SAFE_FREE(fname);
 159                                 SAFE_FREE(sam_sid);
 160                                 return NULL;
 161                         }
 162                 }
 163
 164                 /* Stored the old sid from MACHINE.SID successfully.*/
 165                 SAFE_FREE(fname);
 166                 return sam_sid;
 167         }
 168
 169         SAFE_FREE(fname);
 170
 171         /* we don't have the SID in secrets.tdb, we will need to
 172            generate one and save it */
 173         generate_random_sid(sam_sid);
 174
 175         if (!secrets_store_domain_sid(global_myname(), sam_sid)) {
 176                 DEBUG(0,("pdb_generate_sam_sid: Failed to store generated machine SID.\n"));
 177                 SAFE_FREE(sam_sid);
 178                 return NULL;
 179         }
 180         if (is_dc) {
 181                 if (!secrets_store_domain_sid(lp_workgroup(), sam_sid)) {
 182                         DEBUG(0,("pdb_generate_sam_sid: Failed to store generated domain SID.\n"));
 183                         SAFE_FREE(sam_sid);
 184                         return NULL;
 185                 }
 186         }
 187
 188         return sam_sid;
 189 }
 190
 191 /* return our global_sam_sid */
 192 DOM_SID *get_global_sam_sid(void)
 193 {
 194         if (global_sam_sid != NULL)
 195                 return global_sam_sid;
 196
 197         /* memory for global_sam_sid is allocated in
 198            pdb_generate_sam_sid() as needed */
 199
 200         if (!(global_sam_sid = pdb_generate_sam_sid())) {
 201                 smb_panic("Could not generate a machine SID\n");
 202         }
 203
 204         return global_sam_sid;
 205 }
 206
 207 /**
 208  * Force get_global_sam_sid to requery the backends
 209  */
 210 void reset_global_sam_sid(void)
 211 {
 212         SAFE_FREE(global_sam_sid);
 213 }