r12156: added samdb_domain_sid(), a routine to get the domain sid by looking

up the rootDomainNamingContext in the rootdse, then getting the
objectsid from the root of the domain

diff --git a/source/dsdb/samdb/samdb.c b/source/dsdb/samdb/samdb.c
index 9b63468f99cd079a450a49799edc40479bbf40bb..5e2fa94722c235224e7eef0b13326d956c43d50f 100644 (file)
--- a/source/dsdb/samdb/samdb.c
+++ b/source/dsdb/samdb/samdb.c
@@ -24,6 +24,7 @@
 #include "librpc/gen_ndr/ndr_netlogon.h"
 #include "librpc/gen_ndr/ndr_misc.h"
 #include "lib/ldb/include/ldb.h"
+#include "lib/ldb/include/ldb_errors.h"
 #include "system/time.h"
 #include "system/filesys.h"
 #include "db_wrap.h"
@@ -993,3 +994,68 @@ struct ldb_dn *samdb_base_dn(TALLOC_CTX *mem_ctx)
        }
        return ldb_dn_string_compose(mem_ctx, NULL, "cn=%s", lp_netbios_name());
 }
+
+
+/*
+  work out the domain sid for the current open ldb
+*/
+const struct dom_sid *samdb_domain_sid(struct ldb_context *ldb)
+{
+       const char *attrs[] = { "rootDomainNamingContext", NULL };
+       int ret;
+       struct ldb_result *res = NULL;
+       TALLOC_CTX *tmp_ctx = talloc_new(ldb);
+       struct dom_sid *domain_sid;
+       const char *basedn_s;
+       struct ldb_dn *basedn;
+
+       /* see if we have a cached copy */
+       domain_sid = ldb_get_opaque(ldb, "cache.domain_sid");
+       if (domain_sid) {
+               return domain_sid;
+       }
+
+       basedn = ldb_dn_explode(tmp_ctx, "");
+       if (basedn == NULL) {
+               goto failed;
+       }
+       
+       /* find the basedn of the domain from the rootdse */
+       ret = ldb_search(ldb, basedn, LDB_SCOPE_BASE, NULL, attrs, &res);
+       talloc_steal(tmp_ctx, res);
+       if (ret != LDB_SUCCESS || res->count != 1) {
+               goto failed;
+       }
+
+       basedn_s = ldb_msg_find_string(res->msgs[0], "rootDomainNamingContext", NULL);
+       if (basedn_s == NULL) {
+               goto failed;
+       }
+
+       basedn = ldb_dn_explode(tmp_ctx, basedn_s);
+       if (basedn == NULL) {
+               goto failed;
+       }
+
+       /* find the domain_sid */
+       domain_sid = samdb_search_dom_sid(ldb, tmp_ctx, basedn, 
+                                         "objectSid", "objectClass=domainDNS");
+       if (domain_sid == NULL) {
+               goto failed;
+       }
+
+       /* cache the domain_sid in the ldb */
+       if (ldb_set_opaque(ldb, "cache.domain_sid", domain_sid) != LDB_SUCCESS) {
+               goto failed;
+       }
+
+       talloc_steal(ldb, domain_sid);
+       talloc_free(tmp_ctx);
+
+       return domain_sid;
+
+failed:
+       DEBUG(1,("Failed to find domain_sid for open ldb\n"));
+       talloc_free(tmp_ctx);
+       return NULL;
+}