1 files changed, 103 insertions, 0 deletions
diff --git a/src/libstrongswan/plugins/gcrypt/gcrypt_rng.c b/src/libstrongswan/plugins/gcrypt/gcrypt_rng.c
new file mode 100644
index 000000000..64b4eb8d0
--- /dev/null
+++ b/src/libstrongswan/plugins/gcrypt/gcrypt_rng.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2009 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.
+ */
+
+#include "gcrypt_rng.h"
+
+#include <gcrypt.h>
+
+typedef struct private_gcrypt_rng_t private_gcrypt_rng_t;
+
+/**
+ * Private data of an gcrypt_rng_t object.
+ */
+struct private_gcrypt_rng_t {
+
+	/**
+	 * Public gcrypt_rng_t interface.
+	 */
+	gcrypt_rng_t public;
+	
+	/**
+	 * RNG quality of this instance
+	 */
+	rng_quality_t quality;
+};
+
+/**
+ * Implementation of gcrypt_rng_t.get_bytes.
+ */
+static void get_bytes(private_gcrypt_rng_t *this, size_t bytes,
+					  u_int8_t *buffer)
+{
+	switch (this->quality)
+	{
+		case RNG_WEAK:
+			gcry_create_nonce(buffer, bytes);
+			break;
+		case RNG_STRONG:
+			gcry_randomize(buffer, bytes, GCRY_STRONG_RANDOM);
+			break;
+		case RNG_TRUE:
+			gcry_randomize(buffer, bytes, GCRY_VERY_STRONG_RANDOM);
+			break;
+	}
+}
+
+/**
+ * Implementation of gcrypt_rng_t.allocate_bytes.
+ */
+static void allocate_bytes(private_gcrypt_rng_t *this, size_t bytes,
+						   chunk_t *chunk)
+{
+	*chunk = chunk_alloc(bytes);
+	get_bytes(this, chunk->len, chunk->ptr);
+}
+
+/**
+ * Implementation of gcrypt_rng_t.destroy.
+ */
+static void destroy(private_gcrypt_rng_t *this)
+{
+	free(this);
+}
+
+/*
+ * Described in header.
+ */
+gcrypt_rng_t *gcrypt_rng_create(rng_quality_t quality)
+{
+	private_gcrypt_rng_t *this;
+	
+	switch (quality)
+	{
+		case RNG_WEAK:
+		case RNG_STRONG:
+		case RNG_TRUE:
+			break;
+		default:
+			return NULL;
+	}
+	
+	this = malloc_thing(private_gcrypt_rng_t);
+	
+	this->public.rng.get_bytes = (void (*) (rng_t *, size_t, u_int8_t*)) get_bytes;
+	this->public.rng.allocate_bytes = (void (*) (rng_t *, size_t, chunk_t*)) allocate_bytes;
+	this->public.rng.destroy = (void (*) (rng_t *))destroy;
+	
+	this->quality = quality;
+	
+	return &this->public;
+}
+