The XSUM package of checksum utilities is FreeWare from David R. Conrad
consisting of the following files:

README          This file
XSUM.MAN        The manual, formatted (suitable for printing).
XSUM.DOC        The manual in `plain ASCII' form.
CRC.EXE         Program which generates 32-bit CRCs of files.
MDX.EXE         Program which generates MD4 and MD5 message digests.

This package may be used and distributed freely as long as no changes
are made, all files are distributed, and no more than a nominal fee is
charged for distribution.

No guarantees are made, but you may send bug reports to the author by
any of the ways described in the manual or at the address below.

A note on viruses: The programs have been pronounced clean by F-Prot
2.07, VIRx 2.6d, and CatchMte 1.5.  My thanks to Fridrik Skulason of
Frisk Software, Ross Greenberg of Datawatch Corp., and Tartakan Yetiser
of VDS.  The programs will refuse to run if they are infected with a
non-stealth file infecting virus.

A note on checksums: CRC is intended for error detection.  It is not
suitable for authentication or validation since it is trivial to forge.
MD4 and MD5, however, are `one-way' hash functions.  It is asserted
that it is computationally infeasible to create a file with a specific
message digest.

MD4 and MD5 refer to The RSA Data Security, Inc. MD4 Message-Digest
Algorithm and The RSA Data Security, Inc. MD5 Message-Digest Algorithm.

David R. Conrad, 18 April 1993
David_Conrad@mts.cc.wayne.edu
