Moving charon to libcharon.

1 files changed, 70 insertions, 0 deletions

diff --git a/src/libcharon/network/receiver.h b/src/libcharon/network/receiver.h
new file mode 100644
index 000000000..690d8dbab
--- /dev/null
+++ b/src/libcharon/network/receiver.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2005-2007 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.
+ */
+
+/**
+ * @defgroup receiver receiver
+ * @{ @ingroup network
+ */
+
+#ifndef RECEIVER_H_
+#define RECEIVER_H_
+
+typedef struct receiver_t receiver_t;
+
+#include <library.h>
+#include <utils/host.h>
+
+/**
+ * Receives packets from the socket and adds them to the job queue.
+ *
+ * The receiver starts a thread, wich reads on the blocking socket. A received
+ * packet is preparsed and a process_message_job is queued in the job queue.
+ *
+ * To endure DoS attacks, cookies are enabled when to many IKE_SAs are half
+ * open. The calculation of cookies is slightly different from the proposed
+ * method in RFC4306. We do not include a nonce, because we think the advantage
+ * we gain does not justify the overhead to parse the whole message.
+ * Instead of VersionIdOfSecret, we include a timestamp. This allows us to
+ * find out wich key was used for cookie creation. Further, we can set a
+ * lifetime for the cookie, which allows us to reuse the secret for a longer
+ * time.
+ *		 COOKIE = time | sha1( IPi | SPIi | time | secret )
+ *
+ * The secret is changed after a certain amount of cookies sent. The old
+ * secret is stored to allow a clean migration between secret changes.
+ *
+ * Further, the number of half-initiated IKE_SAs is limited per peer. This
+ * mades it impossible for a peer to flood the server with its real IP address.
+ */
+struct receiver_t {
+
+	/**
+	 * Destroys a receiver_t object.
+	 */
+	void (*destroy) (receiver_t *receiver);
+};
+
+/**
+ * Create a receiver_t object.
+ *
+ * The receiver thread will start working, get data
+ * from the socket and add those packets to the job queue.
+ *
+ * @return	receiver_t object, NULL if initialization fails
+ */
+receiver_t * receiver_create(void);
+
+#endif /** RECEIVER_H_ @}*/