MD5 RSA hashing algorithm in Visual Foxpro

MD5 for VFP is derived from the RSA Data Security, Inc. MD5

Message-Digest Algorithm. MD5 is a hashing function that accepts a

string of arbitrary length and generates a 16-byte encrypted

"message digest" that is (a) unique and (b) not reversible. It is

much more reliable than a checksum. Unlike sys(2007), it does not

produce duplicates. (The probability of a duplicate is estimated

at one case in 2^64; i.e., 18 x 10^18, which should be good enough

for most of us.)

The MD5 algorithm is intended for digital signature applications,

where a large file must be "compressed" in a secure manner before

being encrypted with a private (secret) key under a public-key

cryptosystem such as RSA.

MD5 has been implemented for Visual Foxpro by Duke Lotherington, of

Visual Records in San Diego, by wrapping the C++ function into an

FLL library.

For more information, see the unofficial MD5 Homepage:

"http://userpages.umbc.edu/~mabzug1/cs/md5/md5.html

Download Code


CONTENTS:
MD5.ZIP contains the following components:
MD5.FLL the Visual Foxpro executable library
MD5.TXT This document
SOURCE.ZIP C++ source code for the library
NOTE: Library was originally called VRS.FLL.

USAGE:
Only two statements are required to use the MD5 library.
set library to MD5.FLL
HashCode = MD5HASH(AnyString) && 16-byte result

The library is very small (24k), and very fast. Execution times
are about 140 microseconds for a 256-byte string, measured on a
200-MHz Pentium II.

AUTHOR:
MD5.FLL was produced by:
Duke Lotherington, Visual Records Consulting
3944 Murphy Canyon Rd, San Diego CA 92123
duke@visualrecords.com
and may be freely used and distributed.

This document was prepared by:
Dan Covill
Middleton Consulting Inc., San Diego
dcovill@san.rr.com