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 "../lib/util/util_ldb.h"
  33 #include "ldb_wrap.h"
  34 #include "param/param.h"
  35
  36 /*
  37   RID algorithm from pdb_ldap.c in source3/passdb/
  38   (loosely based on Volkers code)
  39  */
  40 static int samba3sid_next_sid(struct ldb_module *module,
  41                               TALLOC_CTX *mem_ctx, char **sid)
  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                                  "(&(objectClass=sambaDomain)(sambaDomainName=%s))",
  58                                  lpcfg_sam_name(ldb_get_opaque(ldb, "loadparm")));
  59         if (ret != LDB_SUCCESS) {
  60                 ldb_asprintf_errstring(ldb,
  61                                        __location__
  62                                        ": Failed to find domain object - %s",
  63                                        ldb_errstring(ldb));
  64                 talloc_free(tmp_ctx);
  65                 return ret;
  66         }
  67         if (res->count != 1) {
  68                 ldb_asprintf_errstring(ldb,
  69                                        __location__
  70                                        ": Expected exactly 1 domain object - got %u",
  71                                        res->count);
  72                 talloc_free(tmp_ctx);
  73                 return LDB_ERR_OPERATIONS_ERROR;
  74         }
  75         msg = res->msgs[0];
  76
  77         sambaNextRid = ldb_msg_find_attr_as_uint(msg, "sambaNextRid",
  78                                                  (uint32_t) -1);
  79         sambaNextUserRid = ldb_msg_find_attr_as_uint(msg, "sambaNextUserRid",
  80                                                      (uint32_t) -1);
  81         sambaNextGroupRid = ldb_msg_find_attr_as_uint(msg, "sambaNextGroupRid",
  82                                                       (uint32_t) -1);
  83         sambaSID = ldb_msg_find_attr_as_string(msg, "sambaSID", NULL);
  84
  85         if (sambaSID == NULL) {
  86                 ldb_asprintf_errstring(ldb,
  87                                        __location__
  88                                        ": No sambaSID in %s",
  89                                        ldb_dn_get_linearized(msg->dn));
  90                 talloc_free(tmp_ctx);
  91                 return LDB_ERR_OPERATIONS_ERROR;
  92         }
  93
  94         /* choose the highest of the 3 - see pdb_ldap.c for an
  95          * explaination */
  96         rid = sambaNextRid;
  97         if ((sambaNextUserRid != (uint32_t) -1) && (sambaNextUserRid > rid)) {
  98                 rid = sambaNextUserRid;
  99         }
 100         if ((sambaNextGroupRid != (uint32_t) -1) && (sambaNextGroupRid > rid)) {
 101                 rid = sambaNextGroupRid;
 102         }
 103         if (rid == (uint32_t) -1) {
 104                 ldb_asprintf_errstring(ldb,
 105                                        __location__
 106                                        ": No sambaNextRid in %s",
 107                                        ldb_dn_get_linearized(msg->dn));
 108                 talloc_free(tmp_ctx);
 109                 return LDB_ERR_OPERATIONS_ERROR;
 110         }
 111
 112         /* sambaNextRid is actually the previous RID .... */
 113         rid += 1;
 114
 115         (*sid) = talloc_asprintf(tmp_ctx, "%s-%u", sambaSID, rid);
 116         if (!*sid) {
 117                 talloc_free(tmp_ctx);
 118                 return ldb_module_oom(module);
 119         }
 120
 121         ret = dsdb_module_constrainted_update_uint32(module, msg->dn,
 122                                                      "sambaNextRid",
 123                                                      &sambaNextRid, &rid);
 124         if (ret != LDB_SUCCESS) {
 125                 ldb_asprintf_errstring(ldb,
 126                                        __location__
 127                                        ": Failed to update sambaNextRid - %s",
 128                                        ldb_errstring(ldb));
 129                 talloc_free(tmp_ctx);
 130                 return ret;
 131         }
 132
 133         talloc_steal(mem_ctx, *sid);
 134         talloc_free(tmp_ctx);
 135         return LDB_SUCCESS;
 136 }
 137
 138
 139
 140 /* add */
 141 static int samba3sid_add(struct ldb_module *module, struct ldb_request *req)
 142 {
 143         struct ldb_context *ldb;
 144         int ret;
 145         const struct ldb_message *msg = req->op.add.message;
 146         struct ldb_message *new_msg;
 147         char *sid;
 148         struct ldb_request *new_req;
 149
 150         ldb = ldb_module_get_ctx(module);
 151
 152         /* do not manipulate our control entries */
 153         if (ldb_dn_is_special(req->op.add.message->dn)) {
 154                 return ldb_next_request(module, req);
 155         }
 156
 157         if (!samdb_find_attribute(ldb, msg, "objectclass", "posixAccount") &&
 158             !samdb_find_attribute(ldb, msg, "objectclass", "posixGroup")) {
 159                 /* its not a user or a group */
 160                 return ldb_next_request(module, req);
 161         }
 162
 163         if (ldb_msg_find_element(msg, "sambaSID")) {
 164                 /* a SID was supplied */
 165                 return ldb_next_request(module, req);
 166         }
 167
 168         new_msg = ldb_msg_copy_shallow(req, req->op.add.message);
 169         if (!new_msg) {
 170                 return ldb_module_oom(module);
 171         }
 172
 173         ret = samba3sid_next_sid(module, new_msg, &sid);
 174         if (ret != LDB_SUCCESS) {
 175                 return ret;
 176         }
 177
 178         ret = ldb_msg_add_steal_string(new_msg, "sambaSID", sid);
 179         if (ret != LDB_SUCCESS) {
 180                 return ret;
 181         }
 182
 183         ret = ldb_build_add_req(&new_req, ldb, req,
 184                                 new_msg,
 185                                 req->controls,
 186                                 req, dsdb_next_callback,
 187                                 req);
 188         LDB_REQ_SET_LOCATION(new_req);
 189         if (ret != LDB_SUCCESS) {
 190                 return ret;
 191         }
 192
 193         return ldb_next_request(module, new_req);
 194 }
 195
 196 _PUBLIC_ const struct ldb_module_ops ldb_samba3sid_module_ops = {
 197         .name          = "samba3sid",
 198         .add           = samba3sid_add,
 199 };
 200