autofs-5.1.1 - move query dn calculation from do_bind() to do_connect()

From: Ian Kent <raven@themaw.net>

In the ldap lookup module the do_reconnect() call doesn't distinguish
between no entry found and service unavailable.

If service unavailable gets returned from a master map read it results
in autofs not updating the mounts. A notfound return doesn't because it
indicates the map doesn't exist so updating the mounts isn't a problem
as it can be when the source is unavailable.

Start the update of do_reconnect() by moving the query dn calculation
from do_bind() to do_connect().

Signed-off-by: Ian Kent <raven@themaw.net>
---
 CHANGELOG             |    1 +
 modules/lookup_ldap.c |   81 ++++++++++++++++++++++++++++++-------------------
 2 files changed, 51 insertions(+), 31 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index ee078bb..0be1bf2 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -4,6 +4,7 @@
 - revert fix libtirpc name clash.
 - fix left mount count return from umount_multi_triggers().
 - fix return handling in sss lookup module.
+- move query dn calculation from do_bind() to do_connect().
 
 21/04/2015 autofs-5.1.1
 =======================
diff --git a/modules/lookup_ldap.c b/modules/lookup_ldap.c
index 5da613e..ea63736 100644
--- a/modules/lookup_ldap.c
+++ b/modules/lookup_ldap.c
@@ -574,7 +574,7 @@ static int find_query_dn(unsigned logopt, LDAP *ldap, struct lookup_context *ctx
 static int do_bind(unsigned logopt, LDAP *ldap, const char *uri, struct lookup_context *ctxt)
 {
 	char *host = NULL, *nhost;
-	int rv, need_base = 1;
+	int rv;
 
 #ifdef WITH_SASL
 	debug(logopt, MODPREFIX "auth_required: %d, sasl_mech %s",
@@ -610,6 +610,7 @@ static int do_bind(unsigned logopt, LDAP *ldap, const char *uri, struct lookup_c
 	}
 	ldap_memfree(host);
 
+	uris_mutex_lock(ctxt);
 	if (!ctxt->cur_host) {
 		ctxt->cur_host = nhost;
 		if (!(ctxt->format & MAP_FLAG_FORMAT_AMD)) {
@@ -618,43 +619,21 @@ static int do_bind(unsigned logopt, LDAP *ldap, const char *uri, struct lookup_c
 		}
 	} else {
 		/* If connection host has changed update */
-		if (strcmp(ctxt->cur_host, nhost)) {
+		if (!strcmp(ctxt->cur_host, nhost))
+			free(nhost);
+		else {
 			free(ctxt->cur_host);
 			ctxt->cur_host = nhost;
-		} else {
-			free(nhost);
-			need_base = 0;
-		}
-	}
-
-	if (ctxt->schema && ctxt->qdn && !need_base)
-		return 1;
-
-	/*
-	 * If the schema isn't defined in the configuration then check for
-	 * presence of a map dn with a the common schema. Then calculate the
-	 * base dn for searches.
-	 */
-	if (!ctxt->schema) {
-		if (!find_query_dn(logopt, ldap, ctxt)) {
-			warn(logopt,
-			      MODPREFIX "failed to find valid query dn");
-			return 0;
-		}
-	} else if (!(ctxt->format & MAP_FLAG_FORMAT_AMD)) {
-		const char *class = ctxt->schema->map_class;
-		const char *key = ctxt->schema->map_attr;
-		if (!get_query_dn(logopt, ldap, ctxt, class, key)) {
-			error(logopt, MODPREFIX "failed to get query dn");
-			return 0;
 		}
 	}
+	uris_mutex_unlock(ctxt);
 
 	return 1;
 }
 
 static LDAP *do_connect(unsigned logopt, const char *uri, struct lookup_context *ctxt)
 {
+	char *cur_host = NULL;
 	LDAP *ldap;
 
 #ifdef WITH_SASL
@@ -665,13 +644,53 @@ static LDAP *do_connect(unsigned logopt, const char *uri, struct lookup_context
 #endif
 
 	ldap = init_ldap_connection(logopt, uri, ctxt);
-	if (ldap) {
-		if (!do_bind(logopt, ldap, uri, ctxt)) {
+	if (!ldap)
+		goto out;
+
+	uris_mutex_lock(ctxt);
+	if (ctxt->cur_host)
+		cur_host = ctxt->cur_host;
+	uris_mutex_unlock(ctxt);
+
+	if (!do_bind(logopt, ldap, uri, ctxt)) {
+		unbind_ldap_connection(logopt, ldap, ctxt);
+		ldap = NULL;
+		goto out;
+	}
+
+	/* If the lookup schema and the query dn are set and the
+	 * ldap host hasn't changed return.
+	 */
+	uris_mutex_lock(ctxt);
+	if (ctxt->schema && ctxt->qdn && (cur_host == ctxt->cur_host)) {
+		uris_mutex_unlock(ctxt);
+		return ldap;
+	}
+	uris_mutex_unlock(ctxt);
+
+	/*
+	 * If the schema isn't defined in the configuration then check for
+	 * presence of a map dn with a the common schema. Then calculate the
+	 * base dn for searches.
+	 */
+	if (!ctxt->schema) {
+		if (!find_query_dn(logopt, ldap, ctxt)) {
+			unbind_ldap_connection(logopt, ldap, ctxt);
+			ldap = NULL;
+			warn(logopt,
+			      MODPREFIX "failed to find valid query dn");
+			goto out;
+		}
+	} else if (!(ctxt->format & MAP_FLAG_FORMAT_AMD)) {
+		const char *class = ctxt->schema->map_class;
+		const char *key = ctxt->schema->map_attr;
+		if (!get_query_dn(logopt, ldap, ctxt, class, key)) {
 			unbind_ldap_connection(logopt, ldap, ctxt);
 			ldap = NULL;
+			error(logopt, MODPREFIX "failed to get query dn");
 		}
 	}
-
+out:
 	return ldap;
 }