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MD5(1)			     General Commands Manual			  MD5(1)

NAME
     md5,  sha1, rmd160 -- calculate a message-digest fingerprint (checksum) for
     a file

SYNOPSIS
     md5 [-pqrtx] [-s string] [file ...]
     sha1 [-pqrtx] [-s string] [file ...]
     rmd160 [-pqrtx] [-s string] [file ...]

DESCRIPTION
     The md5, sha1 and rmd160 utilities take as input  a  message  of  arbitrary
     length and produce as output a "fingerprint" or "message digest" of the in-
     put.   It	is  conjectured that it is computationally infeasible to produce
     two messages having the same message digest, or to produce any message hav-
     ing a given  prespecified	target	message  digest.   The	MD5,  SHA-1  and
     RIPEMD-160  algorithms  are  intended  for  digital signature applications,
     where a large file must be "compressed" in a secure manner before being en-
     crypted with a private (secret) key under a public-key cryptosystem such as
     RSA.

     MD5 has not yet (2001-09-03) been broken, but sufficient attacks have  been
     made that its security is in some doubt.  The attacks on MD5 are in the na-
     ture  of finding "collisions" -- that is, multiple inputs which hash to the
     same value; it is still unlikely for an attacker to be  able  to  determine
     the exact original input given a hash value.

     The  following  options may be used in any combination and must precede any
     files named on the command line.  The hexadecimal	checksum  of  each  file
     listed on the command line is printed after the options are processed.

     -s string
	     Print a checksum of the given string.

     -p      Echo stdin to stdout and append the checksum to stdout.

     -q      Quiet  mode  -  only the checksum is printed out.	Overrides the -r
	     option.

     -r      Reverses the format of the output.  This helps with  visual  diffs.
	     Does nothing when combined with the -ptx options.

     -t      Run a built-in time trial.

     -x      Run a built-in test script.

DIAGNOSTICS
     The md5, sha1 and rmd160 utilities exit 0 on success, and 1 if at least one
     of the input files could not be read.

SEE ALSO
     cksum(1), md5(3), ripemd(3), sha(3)

     R. Rivest, The MD5 Message-Digest Algorithm, RFC1321.

     J. Burrows, The Secure Hash Standard, FIPS PUB 180-1.

     D. Eastlake and P. Jones, US Secure Hash Algorithm 1, RFC 3174.

     RIPEMD-160 is part of the ISO draft standard "ISO/IEC DIS 10118-3" on dedi-
     cated hash functions.

     Secure Hash Standard (SHS): http://csrc.nist.gov/cryptval/shs.html.

     The			     RIPEMD-160 			   page:
     http://www.esat.kuleuven.ac.be/~bosselae/ripemd160.html.

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

     Support  for  SHA-1  and  RIPEMD-160  has	been  added  by Oliver Eikemeier
     <eik@FreeBSD.org>.

FreeBSD 5.3			  June 6, 2004				  MD5(1)
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