source4/dsdb/samdb/ldb_modules/samba3sid.c

   1 /*
   2    samba3sid module
   3
   4    Copyright (C) Andrew Bartlett 2010
   5    Copyright (C) Andrew Tridgell 2010
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 /*
  22   add objectSid to users and groups using samba3 nextRid method
  23  */
  24
  25 #include "includes.h"
  26 #include "libcli/ldap/ldap_ndr.h"
  27 #include "ldb_module.h"
  28 #include "dsdb/samdb/samdb.h"
  29 #include "dsdb/samdb/ldb_modules/util.h"
  30 #include "libcli/security/security.h"
  31 #include "librpc/gen_ndr/ndr_security.h"
  32 #include "ldb_wrap.h"
  33 #include "param/param.h"
  34
  35 /*
  36   RID algorithm from pdb_ldap.c in source3/passdb/
  37   (loosely based on Volkers code)
  38  */
  39 static int samba3sid_next_sid(struct ldb_module *module,
  40                               TALLOC_CTX *mem_ctx, char **sid,
  41                               struct ldb_request *parent)
  42 {
  43         TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
  44         struct ldb_result *res;
  45         const char *attrs[] = { "sambaNextRid", "sambaNextUserRid",
  46                                 "sambaNextGroupRid", "sambaSID", NULL };
  47         int ret;
  48         struct ldb_context *ldb = ldb_module_get_ctx(module);
  49         struct ldb_message *msg;
  50         uint32_t sambaNextRid, sambaNextGroupRid, sambaNextUserRid, rid;
  51         const char *sambaSID;
  52
  53         ret = dsdb_module_search(module, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE,
  54                                  attrs,
  55                                  DSDB_FLAG_NEXT_MODULE |
  56                                  DSDB_SEARCH_SEARCH_ALL_PARTITIONS,
  57                                  parent,
  58                                  "(&(objectClass=sambaDomain)(sambaDomainName=%s))",
  59                                  lpcfg_sam_name(ldb_get_opaque(ldb, "loadparm")));
  60         if (ret != LDB_SUCCESS) {
  61                 ldb_asprintf_errstring(ldb,
  62                                        __location__
  63                                        ": Failed to find domain object - %s",
  64                                        ldb_errstring(ldb));
  65                 talloc_free(tmp_ctx);
  66                 return ret;
  67         }
  68         if (res->count != 1) {
  69                 ldb_asprintf_errstring(ldb,
  70                                        __location__
  71                                        ": Expected exactly 1 domain object - got %u",
  72                                        res->count);
  73                 talloc_free(tmp_ctx);
  74                 return LDB_ERR_OPERATIONS_ERROR;
  75         }
  76         msg = res->msgs[0];
  77
  78         sambaNextRid = ldb_msg_find_attr_as_uint(msg, "sambaNextRid",
  79                                                  (uint32_t) -1);
  80         sambaNextUserRid = ldb_msg_find_attr_as_uint(msg, "sambaNextUserRid",
  81                                                      (uint32_t) -1);
  82         sambaNextGroupRid = ldb_msg_find_attr_as_uint(msg, "sambaNextGroupRid",
  83                                                       (uint32_t) -1);
  84         sambaSID = ldb_msg_find_attr_as_string(msg, "sambaSID", NULL);
  85
  86         if (sambaSID == NULL) {
  87                 ldb_asprintf_errstring(ldb,
  88                                        __location__
  89                                        ": No sambaSID in %s",
  90                                        ldb_dn_get_linearized(msg->dn));
  91                 talloc_free(tmp_ctx);
  92                 return LDB_ERR_OPERATIONS_ERROR;
  93         }
  94
  95         /* choose the highest of the 3 - see pdb_ldap.c for an
  96          * explanation */
  97         rid = sambaNextRid;
  98         if ((sambaNextUserRid != (uint32_t) -1) && (sambaNextUserRid > rid)) {
  99                 rid = sambaNextUserRid;
 100         }
 101         if ((sambaNextGroupRid != (uint32_t) -1) && (sambaNextGroupRid > rid)) {
 102                 rid = sambaNextGroupRid;
 103         }
 104         if (rid == (uint32_t) -1) {
 105                 ldb_asprintf_errstring(ldb,
 106                                        __location__
 107                                        ": No sambaNextRid in %s",
 108                                        ldb_dn_get_linearized(msg->dn));
 109                 talloc_free(tmp_ctx);
 110                 return LDB_ERR_OPERATIONS_ERROR;
 111         }
 112
 113         /* sambaNextRid is actually the previous RID .... */
 114         rid += 1;
 115
 116         (*sid) = talloc_asprintf(tmp_ctx, "%s-%u", sambaSID, rid);
 117         if (!*sid) {
 118                 talloc_free(tmp_ctx);
 119                 return ldb_module_oom(module);
 120         }
 121
 122         ret = dsdb_module_constrainted_update_uint32(module, msg->dn,
 123                                                      "sambaNextRid",
 124                                                      &sambaNextRid, &rid, parent);
 125         if (ret != LDB_SUCCESS) {
 126                 ldb_asprintf_errstring(ldb,
 127                                        __location__
 128                                        ": Failed to update sambaNextRid - %s",
 129                                        ldb_errstring(ldb));
 130                 talloc_free(tmp_ctx);
 131                 return ret;
 132         }
 133
 134         talloc_steal(mem_ctx, *sid);
 135         talloc_free(tmp_ctx);
 136         return LDB_SUCCESS;
 137 }
 138
 139
 140
 141 /* add */
 142 static int samba3sid_add(struct ldb_module *module, struct ldb_request *req)
 143 {
 144         struct ldb_context *ldb;
 145         int ret;
 146         const struct ldb_message *msg = req->op.add.message;
 147         struct ldb_message *new_msg;
 148         char *sid;
 149         struct ldb_request *new_req;
 150
 151         ldb = ldb_module_get_ctx(module);
 152
 153         /* do not manipulate our control entries */
 154         if (ldb_dn_is_special(req->op.add.message->dn)) {
 155                 return ldb_next_request(module, req);
 156         }
 157
 158         if (!samdb_find_attribute(ldb, msg, "objectclass", "posixAccount") &&
 159             !samdb_find_attribute(ldb, msg, "objectclass", "posixGroup")) {
 160                 /* its not a user or a group */
 161                 return ldb_next_request(module, req);
 162         }
 163
 164         if (ldb_msg_find_element(msg, "sambaSID")) {
 165                 /* a SID was supplied */
 166                 return ldb_next_request(module, req);
 167         }
 168
 169         new_msg = ldb_msg_copy_shallow(req, req->op.add.message);
 170         if (!new_msg) {
 171                 return ldb_module_oom(module);
 172         }
 173
 174         ret = samba3sid_next_sid(module, new_msg, &sid, req);
 175         if (ret != LDB_SUCCESS) {
 176                 return ret;
 177         }
 178
 179         ret = ldb_msg_add_steal_string(new_msg, "sambaSID", sid);
 180         if (ret != LDB_SUCCESS) {
 181                 return ret;
 182         }
 183
 184         ret = ldb_build_add_req(&new_req, ldb, req,
 185                                 new_msg,
 186                                 req->controls,
 187                                 req, dsdb_next_callback,
 188                                 req);
 189         LDB_REQ_SET_LOCATION(new_req);
 190         if (ret != LDB_SUCCESS) {
 191                 return ret;
 192         }
 193
 194         return ldb_next_request(module, new_req);
 195 }
 196
 197 static const struct ldb_module_ops ldb_samba3sid_module_ops = {
 198         .name          = "samba3sid",
 199         .add           = samba3sid_add,
 200 };
 201
 202
 203 int ldb_samba3sid_module_init(const char *version)
 204 {
 205         LDB_MODULE_CHECK_VERSION(version);
 206         return ldb_register_module(&ldb_samba3sid_module_ops);
 207 }