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Diffstat (limited to 'text_cmds/md5/md5.1')
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diff --git a/text_cmds/md5/md5.1 b/text_cmds/md5/md5.1 new file mode 100644 index 0000000..01df82b --- /dev/null +++ b/text_cmds/md5/md5.1 @@ -0,0 +1,95 @@ +.\" $FreeBSD: src/sbin/md5/md5.1,v 1.24 2005/03/10 09:56:39 cperciva Exp $ +.Dd June 6, 2004 +.Dt MD5 1 +.Os +.Sh NAME +.Nm md5 +.Nd calculate a message-digest fingerprint (checksum) for a file +.Sh SYNOPSIS +.Nm md5 +.Op Fl pqrtx +.Op Fl s Ar string +.Op Ar +.Sh DESCRIPTION +The +.Nm +utility takes as input a message of arbitrary length and produces as +output a +.Dq fingerprint +or +.Dq message digest +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 +.Tn MD5 +algorithm is intended for digital signature applications, where a +large file must be +.Dq compressed +in a secure manner before being encrypted with a private +(secret) +key under a public-key cryptosystem such as +.Tn RSA . +.Pp +.Tn MD5's +designer Ron Rivest has stated "md5 and sha1 are both clearly broken (in terms +of collision-resistance)". +So +.Tn MD5 +should be avoided when creating new protocols, or implementing protocols with better options. +.Tn SHA256 +and +.Tn SHA512 +are better options as they have been more resilient to attacks (as of 2009). +.Pp +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. +.Bl -tag -width indent +.It Fl s Ar string +Print a checksum of the given +.Ar string . +.It Fl p +Echo stdin to stdout and append the checksum to stdout. +.It Fl q +Quiet mode - only the checksum is printed out. +Overrides the +.Fl r +option. +.It Fl r +Reverses the format of the output. +This helps with visual diffs. +Does nothing +when combined with the +.Fl ptx +options. +.It Fl t +Run a built-in time trial. +.It Fl x +Run a built-in test script. +.El +.Sh EXIT STATUS +The +.Nm +utility exits 0 on success, +and 1 if at least one of the input files could not be read. +.Sh SEE ALSO +.Xr cksum 1 , +.Xr md5 3 , +.Xr ripemd 3 , +.Xr sha 3 , +.Xr CC_SHA256_Init 3 +.Rs +.%A R. Rivest +.%T The MD5 Message-Digest Algorithm +.%O RFC1321 +.Rs +.%A Vlastimil Klima +.%T Finding MD5 Collisions - a Toy For a Notebook +.%O Cryptology ePrint Archive: Report 2005/075 +.Re +.Sh ACKNOWLEDGMENTS +This program is placed in the public domain for free general use by +RSA Data Security. |