diff --git a/sbin/md5/md5.1 b/sbin/md5/md5.1 index d7407780b16..c08c9892e82 100644 --- a/sbin/md5/md5.1 +++ b/sbin/md5/md5.1 @@ -17,7 +17,8 @@ as output a 128-bit .Dq fingerprint or .Dq message digest -of the input. It is conjectured that it is computationally infeasible to +of the input. +It is conjectured that it is computationally infeasible to produce two messages having 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 @@ -29,13 +30,17 @@ key under a public-key cryptosystem such as .Em RSA . .Pp 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 nature of finding ``collisions'' \- that is, multiple +made that its security is in some doubt. +The attacks on MD5 +are in the nature of finding +.Dq collisions +\(em 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. .Pp The following options may be used in any combination and must -precede any files named on the command line. The MD5 +precede any files named on the command line. +The MD5 sum of each file listed on the command line is printed after the options are processed. .Bl -tag -width indent @@ -45,11 +50,14 @@ Print a checksum of the given .It Fl p Echo stdin to stdout and appends the MD5 sum to stdout. .It Fl q -Quiet mode - only the MD5 sum is printed out. Overrides the +Quiet mode - only the MD5 sum is printed out. +Overrides the .Fl r option. .It Fl r -Reverses the format of the output. This helps with visual diffs. Does nothing +Reverses the format of the output. +This helps with visual diffs. +Does nothing when combined with the .Fl ptx options.