Imported existing code

indra/llmessage/llblowfishcipher.cpp

@@ -0,0 +1,131 @@
+/** 
+ * @file llblowfishcipher.cpp
+ * @brief Wrapper around OpenSSL Blowfish encryption algorithm.
+ *
+ * $LicenseInfo:firstyear=2007&license=viewergpl$
+ * 
+ * Copyright (c) 2007-2009, Linden Research, Inc.
+ * 
+ * Second Life Viewer Source Code
+ * The source code in this file ("Source Code") is provided by Linden Lab
+ * to you under the terms of the GNU General Public License, version 2.0
+ * ("GPL"), unless you have obtained a separate licensing agreement
+ * ("Other License"), formally executed by you and Linden Lab.  Terms of
+ * the GPL can be found in doc/GPL-license.txt in this distribution, or
+ * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
+ * 
+ * There are special exceptions to the terms and conditions of the GPL as
+ * it is applied to this Source Code. View the full text of the exception
+ * in the file doc/FLOSS-exception.txt in this software distribution, or
+ * online at
+ * http://secondlifegrid.net/programs/open_source/licensing/flossexception
+ * 
+ * By copying, modifying or distributing this software, you acknowledge
+ * that you have read and understood your obligations described above,
+ * and agree to abide by those obligations.
+ * 
+ * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
+ * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
+ * COMPLETENESS OR PERFORMANCE.
+ * $/LicenseInfo$
+ */
+
+#include "linden_common.h"
+#include "llblowfishcipher.h"
+#include <openssl/evp.h>
+
+
+LLBlowfishCipher::LLBlowfishCipher(const U8* secret, size_t secret_size)
+:	LLCipher()
+{
+	llassert(secret);
+
+	mSecretSize = secret_size;
+	mSecret = new U8[mSecretSize];
+	memcpy(mSecret, secret, mSecretSize);
+}
+
+LLBlowfishCipher::~LLBlowfishCipher()
+{
+	delete [] mSecret;
+	mSecret = NULL;
+}
+
+// virtual
+U32 LLBlowfishCipher::encrypt(const U8* src, U32 src_len, U8* dst, U32 dst_len)
+{
+	if (!src || !src_len || !dst || !dst_len) return 0;
+	if (src_len > dst_len) return 0;
+
+	// OpenSSL uses "cipher contexts" to hold encryption parameters.
+    EVP_CIPHER_CTX context;
+    EVP_CIPHER_CTX_init(&context);
+
+	// We want a blowfish cyclic block chain cipher, but need to set 
+	// the key length before we pass in a key, so call EncryptInit 
+	// first with NULLs.
+	EVP_EncryptInit_ex(&context, EVP_bf_cbc(), NULL, NULL, NULL);
+	EVP_CIPHER_CTX_set_key_length(&context, (int)mSecretSize);
+	
+	// Complete initialization.  Per EVP_EncryptInit man page, the
+	// cipher pointer must be NULL.  Apparently initial_vector must
+	// be 8 bytes for blowfish, as this is the block size.
+    unsigned char initial_vector[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
+	EVP_EncryptInit_ex(&context, NULL, NULL, mSecret, initial_vector);
+
+    int blocksize = EVP_CIPHER_CTX_block_size(&context);
+    int keylen = EVP_CIPHER_CTX_key_length(&context);
+    int iv_length = EVP_CIPHER_CTX_iv_length(&context);
+    lldebugs << "LLBlowfishCipher blocksize " << blocksize
+		<< " keylen " << keylen
+		<< " iv_len " << iv_length
+		<< llendl;
+
+	int output_len = 0;
+	int temp_len = 0;
+	if (!EVP_EncryptUpdate(&context,
+			dst,
+			&output_len,
+			src,
+			src_len))
+	{
+		llwarns << "LLBlowfishCipher::encrypt EVP_EncryptUpdate failure" << llendl;
+		goto ERROR;
+	}
+
+	// There may be some final data left to encrypt if the input is
+	// not an exact multiple of the block size.
+	if (!EVP_EncryptFinal_ex(&context, (unsigned char*)(dst + output_len), &temp_len))
+	{
+		llwarns << "LLBlowfishCipher::encrypt EVP_EncryptFinal failure" << llendl;
+		goto ERROR;
+	}
+	output_len += temp_len;
+
+	EVP_CIPHER_CTX_cleanup(&context);
+	return output_len;
+
+ERROR:
+	EVP_CIPHER_CTX_cleanup(&context);
+	return 0;
+}
+
+// virtual
+U32 LLBlowfishCipher::decrypt(const U8* src, U32 src_len, U8* dst, U32 dst_len)
+{
+	llerrs << "LLBlowfishCipher decrypt unsupported" << llendl;
+	return 0;
+}
+
+// virtual
+U32 LLBlowfishCipher::requiredEncryptionSpace(U32 len) const
+{
+	// *HACK: We know blowfish uses an 8 byte block size.
+	// Oddly, sometimes EVP_Encrypt produces an extra block
+	// if the input is an exact multiple of the block size.
+	// So round up.
+	const U32 BLOCK_SIZE = 8;
+	len += BLOCK_SIZE;
+	len -= (len % BLOCK_SIZE);
+	return len;
+}