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         int sambaNextRid, sambaNextGroupRid, sambaNextUserRid;
  50         struct ldb_message *msg;
  51         uint32_t rid;
  52         const char *sambaSID;
  53
  54         ret = dsdb_module_search(module, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE,
  55                                  attrs, DSDB_SEARCH_SEARCH_ALL_PARTITIONS,
  56                                  "(&(objectClass=sambaDomain)(sambaDomainName=%s))",
  57                                  lp_sam_name(ldb_get_opaque(ldb, "loadparm")));
  58         if (ret != LDB_SUCCESS) {
  59                 ldb_asprintf_errstring(ldb,
  60                                        __location__
  61                                        ": Failed to find domain object - %s",
  62                                        ldb_errstring(ldb));
  63                 talloc_free(tmp_ctx);
  64                 return ret;
  65         }
  66         if (res->count != 1) {
  67                 ldb_asprintf_errstring(ldb,
  68                                        __location__
  69                                        ": Expected exactly 1 domain object - got %u",
  70                                        res->count);
  71                 talloc_free(tmp_ctx);
  72                 return ret;
  73         }
  74         msg = res->msgs[0];
  75
  76         sambaNextRid = ldb_msg_find_attr_as_uint(msg, "sambaNextRid", -1);
  77         sambaNextUserRid = ldb_msg_find_attr_as_uint(msg, "sambaNextUserRid", -1);
  78         sambaNextGroupRid = ldb_msg_find_attr_as_uint(msg, "sambaNextGroupRid", -1);
  79         sambaSID = ldb_msg_find_attr_as_string(msg, "sambaSID", NULL);
  80
  81         if (sambaSID == NULL) {
  82                 ldb_asprintf_errstring(ldb,
  83                                        __location__
  84                                        ": No sambaSID in %s",
  85                                        ldb_dn_get_linearized(msg->dn));
  86                 talloc_free(tmp_ctx);
  87                 return ret;
  88         }
  89
  90         /* choose the highest of the 3 - see pdb_ldap.c for an
  91          * explanation */
  92         rid = sambaNextRid;
  93         if (sambaNextUserRid > rid) {
  94                 rid = sambaNextUserRid;
  95         }
  96         if (sambaNextGroupRid > rid) {
  97                 rid = sambaNextGroupRid;
  98         }
  99         if (rid == -1) {
 100                 ldb_asprintf_errstring(ldb,
 101                                        __location__
 102                                        ": No sambaNextRid in %s",
 103                                        ldb_dn_get_linearized(msg->dn));
 104                 talloc_free(tmp_ctx);
 105                 return ret;
 106         }
 107
 108         (*sid) = talloc_asprintf(tmp_ctx, "%s-%u", sambaSID, rid);
 109         if (!*sid) {
 110                 ldb_module_oom(module);
 111                 talloc_free(tmp_ctx);
 112                 return LDB_ERR_OPERATIONS_ERROR;
 113         }
 114
 115         ret = dsdb_module_constrainted_update_integer(module, msg->dn,
 116                                                       "sambaNextRid",
 117                                                       sambaNextRid, rid+1);
 118         if (ret != LDB_SUCCESS) {
 119                 ldb_asprintf_errstring(ldb,
 120                                        __location__
 121                                        ": Failed to update sambaNextRid - %s",
 122                                        ldb_errstring(ldb));
 123                 talloc_free(tmp_ctx);
 124                 return ret;
 125         }
 126
 127         talloc_steal(mem_ctx, *sid);
 128         talloc_free(tmp_ctx);
 129         return LDB_SUCCESS;
 130 }
 131
 132
 133
 134 /* add */
 135 static int samba3sid_add(struct ldb_module *module, struct ldb_request *req)
 136 {
 137         struct ldb_context *ldb;
 138         int ret;
 139         const struct ldb_message *msg = req->op.add.message;
 140         struct ldb_message *new_msg;
 141         char *sid;
 142         struct ldb_request *new_req;
 143
 144         ldb = ldb_module_get_ctx(module);
 145
 146         /* do not manipulate our control entries */
 147         if (ldb_dn_is_special(req->op.add.message->dn)) {
 148                 return ldb_next_request(module, req);
 149         }
 150
 151         if (!samdb_find_attribute(ldb, msg, "objectclass", "posixAccount") &&
 152             !samdb_find_attribute(ldb, msg, "objectclass", "posixGroup")) {
 153                 /* its not a user or a group */
 154                 return ldb_next_request(module, req);
 155         }
 156
 157         if (ldb_msg_find_element(msg, "sambaSID")) {
 158                 /* a SID was supplied */
 159                 return ldb_next_request(module, req);
 160         }
 161
 162         new_msg = ldb_msg_copy_shallow(req, req->op.add.message);
 163         if (!new_msg) {
 164                 ldb_module_oom(module);
 165                 return LDB_ERR_OPERATIONS_ERROR;
 166         }
 167
 168         ret = samba3sid_next_sid(module, new_msg, &sid);
 169         if (ret != LDB_SUCCESS) {
 170                 return ret;
 171         }
 172
 173         ret = ldb_msg_add_steal_string(new_msg, "sambaSID", sid);
 174         if (ret != LDB_SUCCESS) {
 175                 return ret;
 176         }
 177
 178         ret = ldb_build_add_req(&new_req, ldb, req,
 179                                 new_msg,
 180                                 req->controls,
 181                                 req, dsdb_next_callback,
 182                                 req);
 183         if (ret != LDB_SUCCESS) {
 184                 return ret;
 185         }
 186
 187         return ldb_next_request(module, new_req);
 188 }
 189
 190 _PUBLIC_ const struct ldb_module_ops ldb_samba3sid_module_ops = {
 191         .name          = "samba3sid",
 192         .add           = samba3sid_add,
 193 };
 194