MD5(1)                     OpenBSD Reference Manual                     MD5(1)

NAME
     md5 - calculate a message-digest fingerprint (checksum) for a file

SYNOPSIS
     md5 [-ptx] [-s string] [file ...]

DESCRIPTION
     md5 takes as input a message of arbitrary length and produces as output a
     128-bit "fingerprint" or "message digest" of the input.  It is conjec-
     tured that it is computationally infeasible to produce two messages hav-
     ing the same message digest, or to produce any message having a given
     prespecified target message digest.  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 un-
     der a public-key cryptosystem such as RSA.

OPTIONS
     The following four options may be used in any combination and must pre-
     cede any files named on the command line.  The MD5 sum of each file list-
     ed on the command line is printed after the options are processed.

     -s string   Prints a checksum of the given string.

     -p          Echos stdin to stdout and appends the MD5 sum to stdout.

     -t          Runs a built-in time trial.

     -x          Runs a built-in test script.

SEE ALSO
     cksum(1),  rmd160(1),  sha1(1)

     RFC 1321 describes in detail the MD2, MD4, and MD5 message-digest algo-
     rithms.

ACKNOWLEDGEMENTS
     This program is placed in the public domain for free general use by RSA
     Data Security.

OpenBSD 2.6                    February 14, 1994                             1
