diff --git a/src/3rdparty/md5/md5.h b/src/3rdparty/md5/md5.h
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+/* $Id$ */
+
+/** @file md5.h Functions to create MD5 checksums. */
+
+/*
+  Copyright (C) 1999, 2002 Aladdin Enterprises.  All rights reserved.
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+
+  L. Peter Deutsch
+  ghost@aladdin.com
+
+ */
+
+/*
+  Independent implementation of MD5 (RFC 1321).
+
+  This code implements the MD5 Algorithm defined in RFC 1321, whose
+  text is available at
+  http://www.ietf.org/rfc/rfc1321.txt
+  The code is derived from the text of the RFC, including the test suite
+  (section A.5) but excluding the rest of Appendix A.  It does not include
+  any code or documentation that is identified in the RFC as being
+  copyrighted.
+
+  The original and principal author of md5.h is L. Peter Deutsch
+  <ghost@aladdin.com>.  Other authors are noted in the change history
+  that follows (in reverse chronological order):
+
+  2007-12-24 Changed to C++ and adapted to OpenTTD source
+  2002-04-13 lpd Removed support for non-ANSI compilers; removed
+             references to Ghostscript; clarified derivation from RFC 1321;
+             now handles byte order either statically or dynamically.
+  1999-11-04 lpd Edited comments slightly for automatic TOC extraction.
+  1999-10-18 lpd Fixed typo in header comment (ansi2knr rather than md5);
+             added conditionalization for C++ compilation from Martin
+             Purschke <purschke@bnl.gov>.
+  1999-05-03 lpd Original version.
+ */
+
+#ifndef MD5_INCLUDED
+#define MD5_INCLUDED
+
+/*
+ * This package supports both compile-time and run-time determination of CPU
+ * byte order.  If ARCH_IS_BIG_ENDIAN is defined as 0, the code will be
+ * compiled to run only on little-endian CPUs; if ARCH_IS_BIG_ENDIAN is
+ * defined as non-zero, the code will be compiled to run only on big-endian
+ * CPUs; if ARCH_IS_BIG_ENDIAN is not defined, the code will be compiled to
+ * run on either big- or little-endian CPUs, but will run slightly less
+ * efficiently on either one than if ARCH_IS_BIG_ENDIAN is defined.
+ */
+
+struct Md5 {
+private:
+	uint32 count[2]; ///< message length in bits, lsw first
+	uint32 abcd[4];  ///< digest buffer
+	uint8 buf[64];   ///< accumulate block
+
+	void Process(const uint8 *data);
+
+public:
+	Md5();
+	void Append(const void *data, const size_t nbytes);
+	void Finish(uint8 digest[16]);
+};
+
+#endif /* MD5_INCLUDED */