From: Andrew Bartlett <abartlet@samba.org>
Date: Thu, 14 Dec 2017 23:30:50 +0000 (+1300)
Subject: dns_server: Do the exact match query first, then do the wildcard lookup
X-Git-Tag: talloc-2.1.11~137
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=3efc879d98ba136d4d70e0e2d77fac9614186ab3;p=thirdparty%2Fsamba.git

dns_server: Do the exact match query first, then do the wildcard lookup

The wildcard lookup is SCOPE_ONELEVEL combined with an index on the name
attribute.  This is not as efficient as a base DN lookup, so we try for
that first.

A not-found and wildcard response will still fall back to the ONELEVEL
index.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13191

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Garming Sam <garming@catalyst.net.nz>
---

diff --git a/source4/dns_server/dnsserver_common.c b/source4/dns_server/dnsserver_common.c
index 3e161f81ac7..6c7ab802575 100644
--- a/source4/dns_server/dnsserver_common.c
+++ b/source4/dns_server/dnsserver_common.c
@@ -563,6 +563,20 @@ WERROR dns_common_wildcard_lookup(struct ldb_context *samdb,
 		return werr;
 	}
 
+	/*
+	 * Do a point search first, then fall back to a wildcard
+	 * lookup if it does not exist
+	 */
+	werr = dns_common_lookup(samdb,
+				 mem_ctx,
+				 dn,
+				 records,
+				 num_records,
+				 NULL);
+	if (!W_ERROR_EQUAL(werr, WERR_DNS_ERROR_NAME_DOES_NOT_EXIST)) {
+		return werr;
+	}
+
 	ret = dns_wildcard_lookup(samdb, mem_ctx, dn, &msg);
 	if (ret == LDB_ERR_OPERATIONS_ERROR) {
 		return DNS_ERR(SERVER_FAILURE);