1 files changed, 139 insertions, 0 deletions
diff --git a/src/libstrongswan/crypto/signers/mac_signer.c b/src/libstrongswan/crypto/signers/mac_signer.c
new file mode 100644
index 000000000..7c52aa305
--- /dev/null
+++ b/src/libstrongswan/crypto/signers/mac_signer.c
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2005-2008 Martin Willi
+ * Copyright (C) 2005 Jan Hutter
+ * 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.
+ */
+
+#include "mac_signer.h"
+
+typedef struct private_signer_t private_signer_t;
+
+/**
+ * Private data of a mac_signer_t object.
+ */
+struct private_signer_t {
+
+	/**
+	 * Public interface
+	 */
+	signer_t public;
+
+	/**
+	 * MAC to use
+	 */
+	mac_t *mac;
+
+	/**
+	 * Truncation of MAC output
+	 */
+	size_t truncation;
+};
+
+METHOD(signer_t, get_signature, bool,
+	private_signer_t *this, chunk_t data, u_int8_t *buffer)
+{
+	if (buffer)
+	{
+		u_int8_t mac[this->mac->get_mac_size(this->mac)];
+
+		if (!this->mac->get_mac(this->mac, data, mac))
+		{
+			return FALSE;
+		}
+		memcpy(buffer, mac, this->truncation);
+		return TRUE;
+	}
+	return this->mac->get_mac(this->mac, data, NULL);
+}
+
+METHOD(signer_t, allocate_signature, bool,
+	private_signer_t *this, chunk_t data, chunk_t *chunk)
+{
+	if (chunk)
+	{
+		u_int8_t mac[this->mac->get_mac_size(this->mac)];
+
+		if (!this->mac->get_mac(this->mac, data, mac))
+		{
+			return FALSE;
+		}
+		*chunk = chunk_alloc(this->truncation);
+		memcpy(chunk->ptr, mac, this->truncation);
+		return TRUE;
+	}
+	return this->mac->get_mac(this->mac, data, NULL);
+}
+
+METHOD(signer_t, verify_signature, bool,
+	private_signer_t *this, chunk_t data, chunk_t signature)
+{
+	u_int8_t mac[this->mac->get_mac_size(this->mac)];
+
+	if (signature.len != this->truncation)
+	{
+		return FALSE;
+	}
+	return this->mac->get_mac(this->mac, data, mac) &&
+		   memeq(signature.ptr, mac, this->truncation);
+}
+
+METHOD(signer_t, get_key_size, size_t,
+	private_signer_t *this)
+{
+	return this->mac->get_mac_size(this->mac);
+}
+
+METHOD(signer_t, get_block_size, size_t,
+	private_signer_t *this)
+{
+	return this->truncation;
+}
+
+METHOD(signer_t, set_key, bool,
+	private_signer_t *this, chunk_t key)
+{
+	return this->mac->set_key(this->mac, key);
+}
+
+METHOD(signer_t, destroy, void,
+	private_signer_t *this)
+{
+	this->mac->destroy(this->mac);
+	free(this);
+}
+
+/*
+ * Described in header
+ */
+signer_t *mac_signer_create(mac_t *mac, size_t len)
+{
+	private_signer_t *this;
+
+	INIT(this,
+		.public = {
+			.get_signature = _get_signature,
+			.allocate_signature = _allocate_signature,
+			.verify_signature = _verify_signature,
+			.get_block_size = _get_block_size,
+			.get_key_size = _get_key_size,
+			.set_key = _set_key,
+			.destroy = _destroy,
+		},
+		.truncation = min(len, mac->get_mac_size(mac)),
+		.mac = mac,
+	);
+
+	return &this->public;
+}
+