Implemented the PRF_KEYED_SHA1 algorithm in the openssl plugin

2010-03-08 13:16:12 +01:00
parent 33e4ee59ed
commit 40f130dab3
6 changed files with 208 additions and 12 deletions
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2010 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 "openssl_sha1_prf.h"
+
+#include <openssl/sha.h>
+
+typedef struct private_openssl_sha1_prf_t private_openssl_sha1_prf_t;
+
+/**
+ * Private data of an openssl_sha1_prf_t object.
+ */
+struct private_openssl_sha1_prf_t {
+
+	/**
+	 * Public openssl_sha1_prf_t interface.
+	 */
+	openssl_sha1_prf_t public;
+
+	/**
+	 * SHA1 context
+	 */
+	SHA_CTX ctx;
+};
+
+METHOD(prf_t, get_bytes, void,
+	private_openssl_sha1_prf_t *this, chunk_t seed, u_int8_t *bytes)
+{
+	SHA1_Update(&this->ctx, seed.ptr, seed.len);
+
+	if (bytes)
+	{
+		u_int32_t *hash = (u_int32_t*)bytes;
+
+		hash[0] = htonl(this->ctx.h0);
+		hash[1] = htonl(this->ctx.h1);
+		hash[2] = htonl(this->ctx.h2);
+		hash[3] = htonl(this->ctx.h3);
+		hash[4] = htonl(this->ctx.h4);
+	}
+}
+
+METHOD(prf_t, get_block_size, size_t,
+	private_openssl_sha1_prf_t *this)
+{
+	return HASH_SIZE_SHA1;
+}
+
+METHOD(prf_t, allocate_bytes, void,
+	private_openssl_sha1_prf_t *this, chunk_t seed, chunk_t *chunk)
+{
+	if (chunk)
+	{
+		*chunk = chunk_alloc(HASH_SIZE_SHA1);
+		get_bytes(this, seed, chunk->ptr);
+	}
+	else
+	{
+		get_bytes(this, seed, NULL);
+	}
+}
+
+METHOD(prf_t, get_key_size, size_t,
+	private_openssl_sha1_prf_t *this)
+{
+	return HASH_SIZE_SHA1;
+}
+
+METHOD(prf_t, set_key, void,
+	private_openssl_sha1_prf_t *this, chunk_t key)
+{
+	SHA1_Init(&this->ctx);
+
+	if (key.len >= 4)
+	{
+		this->ctx.h0 ^= untoh32(key.ptr);
+	}
+	if (key.len >= 8)
+	{
+		this->ctx.h1 ^= untoh32(key.ptr + 4);
+	}
+	if (key.len >= 12)
+	{
+		this->ctx.h2 ^= untoh32(key.ptr + 8);
+	}
+	if (key.len >= 16)
+	{
+		this->ctx.h3 ^= untoh32(key.ptr + 12);
+	}
+	if (key.len >= 20)
+	{
+		this->ctx.h4 ^= untoh32(key.ptr + 16);
+	}
+}
+
+METHOD(prf_t, destroy, void,
+	private_openssl_sha1_prf_t *this)
+{
+	free(this);
+}
+
+/**
+ * See header
+ */
+openssl_sha1_prf_t *openssl_sha1_prf_create(pseudo_random_function_t algo)
+{
+	private_openssl_sha1_prf_t *this;
+
+	if (algo != PRF_KEYED_SHA1)
+	{
+		return NULL;
+	}
+
+	INIT(this,
+		.public.prf = {
+			.get_block_size = _get_block_size,
+			.get_bytes = _get_bytes,
+			.allocate_bytes = _allocate_bytes,
+			.get_key_size = _get_key_size,
+			.set_key = _set_key,
+			.destroy = _destroy,
+		},
+	);
+
+	return &this->public;
+}
+