7 .Nd calculate a message-digest fingerprint (checksum) for a file
16 utility takes as input a message of arbitrary length and produces
22 It is conjectured that it is computationally infeasible to
23 produce two messages having the same message digest, or to produce any
24 message having a given prespecified target message digest.
25 The MD5 algorithm is intended for digital signature applications, where a
28 in a secure manner before being encrypted with a private
30 key under a public-key cryptosystem such as
33 MD5 has not yet (2001-09-03) been broken, but sufficient attacks have been
34 made that its security is in some doubt.
36 are in the nature of finding
38 \(em that is, multiple
39 inputs which hash to the same value; it is still unlikely for an attacker
40 to be able to determine the exact original input given a hash value.
42 The following options may be used in any combination and must
43 precede any files named on the command line.
45 sum of each file listed on the command line is printed after the options
47 .Bl -tag -width indent
49 Print a checksum of the given
52 Echo stdin to stdout and appends the MD5 sum to stdout.
54 Quiet mode - only the MD5 sum is printed out.
59 Reverses the format of the output.
60 This helps with visual diffs.
62 when combined with the
66 Run a built-in time trial.
68 Run a built-in test script.
73 utility exits 0 on success,
74 and 1 if at least one of the input files could not be read.
79 .%T The MD5 Message-Digest Algorithm
83 This program is placed in the public domain for free general use by