Imported existing code

indra/llmessage/llnullcipher.cpp

@@ -0,0 +1,64 @@
+/** 
+ * @file llnullcipher.cpp
+ * @brief Implementation of a cipher which does not encrypt.
+ *
+ * $LicenseInfo:firstyear=2003&license=viewergpl$
+ * 
+ * Copyright (c) 2003-2009, 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 "llnullcipher.h"
+
+///----------------------------------------------------------------------------
+/// Class LLNullCipher
+///----------------------------------------------------------------------------
+
+U32  LLNullCipher::encrypt(const U8* src, U32 src_len, U8* dst, U32 dst_len)
+{
+	if((src_len == dst_len) && src && dst)
+	{
+		memmove(dst, src, src_len);
+		return src_len;
+	}
+	return 0;
+}
+
+U32 LLNullCipher::decrypt(const U8* src, U32 src_len, U8* dst, U32 dst_len)
+{
+	if((src_len == dst_len) && src && dst)
+	{
+		memmove(dst, src, src_len);
+		return src_len;
+	}
+	return 0;
+}
+
+U32 LLNullCipher::requiredEncryptionSpace(U32 len) const
+{
+	return len;
+}