added API for random number generators, served through credential factory

ported randomizer_t to a rng_t on top of /dev/(u)random (plugin random)

src/libstrongswan/crypto/rngs/rng.c

@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2008 Martin Willi
+ * 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.
+ *
+ * $Id$
+ */
+
+#include "rng.h"
+
+ENUM(rng_quality_names, RNG_WEAK, RNG_REAL,
+	"RNG_WEAK",
+	"RNG_STRONG",
+	"RNG_REAL",
+);

src/libstrongswan/crypto/rngs/rng.h

@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2008 Martin Willi
+ * 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.
+ *
+ * $Id: rng.h 3619 2008-03-19 14:02:52Z martin $
+ */
+ 
+/**
+ * @defgroup rng rng
+ * @{ @ingroup crypto
+ */
+
+#ifndef RNG_H_
+#define RNG_H_
+
+typedef enum rng_quality_t rng_quality_t;
+typedef struct rng_t rng_t;
+
+#include <library.h>
+
+/**
+ * Quality of generated random bytes.
+ */
+enum rng_quality_t {
+	/** weak randomness, usable for nonces, IVs */
+	RNG_WEAK,
+	/** stronger randomness, usable for session keys */
+	RNG_STRONG,
+	/** real random, key material */
+	RNG_REAL,
+};
+
+/**
+ * enum name for rng_quality_t.
+ */
+extern enum_name_t *rng_quality_names;
+
+/**
+ * Generic interface for random number generators.
+ */
+struct rng_t {
+
+	/**
+	 * Generates random bytes and writes them in the buffer.
+	 *
+	 * @param len		number of bytes to get
+	 * @param buffer	pointer where the generated bytes will be written
+	 */
+	void (*get_bytes) (rng_t *this, u_int len, u_int8_t *buffer);
+	
+	/**
+	 * Generates random bytes and allocate space for them.
+	 * 
+	 * @param len		number of bytes to get
+	 * @param chunk		chunk which will hold generated bytes
+	 */
+	void (*allocate_bytes) (rng_t *this, u_int len, chunk_t *chunk);
+	
+	/**
+	 * Destroys a rng object.
+	 */
+	void (*destroy) (rng_t *this);
+};
+
+#endif /*RNG_H_ @} */