Added interface for DNS resolvers

src/libstrongswan/resolver/resolver.h

@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2011-2012 Reto Guadagnini
+ * Hochschule fuer Technik Rapperswil
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+/**
+ * @defgroup resolveri resolver
+ * @{ @ingroup resolver
+ */
+
+#ifndef RESOLVER_H_
+#define RESOLVER_H_
+
+typedef struct resolver_t resolver_t;
+
+/**
+ * Constructor function which creates resolver instances.
+ *
+ * Creates a new DNS resolver with settings from the file resolv_conf and
+ * keys from the file ta_file as DNSSEC trust anchor.
+ *
+ * @param resolv_conf	path to the file resolv.conf
+ * @param ta_file		path to a file with the DNSSEC trust anchors
+ * @return				resolver instance
+ */
+typedef resolver_t* (*resolver_constructor_t)(char *resolv_conf, char *ta_file);
+
+#include <resolver/resolver_response.h>
+#include <resolver/rr_set.h>
+#include <resolver/rr.h>
+
+/**
+ * Interface of a security-aware DNS resolver.
+ *
+ */
+struct resolver_t {
+
+	/**
+	 * Perform a DNS query.
+	 *
+	 * @param domain		domain (FQDN) to query
+	 * @param rr_class		class of the desired RRs
+	 * @param rr_type		type of the desired RRs
+	 * @return				response to the query, NULL on failure
+	 */
+	resolver_response_t *(*query)(resolver_t *this, char *domain,
+								  rr_class_t rr_class, rr_type_t rr_type);
+
+	/**
+	 * Destroy the resolver instance.
+	 */
+	void (*destroy)(resolver_t *this);
+};
+
+#endif /** RESOLVER_H_ @}*/