package Digest::MD5; use strict; use vars qw($VERSION @ISA @EXPORT_OK); $VERSION = '2.11'; # $Date: 2000/08/19 17:37:00 $ require Exporter; *import = \&Exporter::import; @EXPORT_OK = qw(md5 md5_hex md5_base64); require DynaLoader; @ISA=qw(DynaLoader); eval { Digest::MD5->bootstrap($VERSION); }; if ($@) { # Try to load the pure perl version require Digest::Perl::MD5; Digest::Perl::MD5->import(qw(md5 md5_hex md5_base64)); push(@ISA, "Digest::Perl::MD5"); # make OO interface work } else { *reset = \&new; } 1; __END__ =head1 NAME Digest::MD5 - Perl interface to the MD5 Algorithm =head1 SYNOPSIS # Functional style use Digest::MD5 qw(md5 md5_hex md5_base64); $digest = md5($data); $digest = md5_hex($data); $digest = md5_base64($data); # OO style use Digest::MD5; $ctx = Digest::MD5->new; $ctx->add($data); $ctx->addfile(*FILE); $digest = $ctx->digest; $digest = $ctx->hexdigest; $digest = $ctx->b64digest; =head1 DESCRIPTION The C module allows you to use the RSA Data Security Inc. MD5 Message Digest algorithm from within Perl programs. The algorithm takes as input a message of arbitrary length and produces as output a 128-bit "fingerprint" or "message digest" of the input. The C module provide a procedural interface for simple use, as well as an object oriented interface that can handle messages of arbitrary length and which can read files directly. A binary digest will be 16 bytes long. A hex digest will be 32 characters long. A base64 digest will be 22 characters long. =head1 FUNCTIONS The following functions can be exported from the C module. No functions are exported by default. =over 4 =item md5($data,...) This function will concatenate all arguments, calculate the MD5 digest of this "message", and return it in binary form. =item md5_hex($data,...) Same as md5(), but will return the digest in hexadecimal form. =item md5_base64($data,...) Same as md5(), but will return the digest as a base64 encoded string. =back =head1 METHODS The following methods are available: =over 4 =item $md5 = Digest::MD5->new The constructor returns a new C object which encapsulate the state of the MD5 message-digest algorithm. You can add data to the object and finally ask for the digest. If called as a instance method (i.e. $md5->new) it will just reset the state the object to the state of a newly created object. No new object is created in this case. =item $md5->reset This is just an alias for $md5->new. =item $md5->add($data,...) The $data provided as argument are appended to the message we calculate the digest for. The return value is the $md5 object itself. =item $md5->addfile($io_handle) The $io_handle is read until EOF and the content is appended to the message we calculate the digest for. The return value is the $md5 object itself. =item $md5->digest Return the binary digest for the message. Note that the C operation is effectively a destructive, read-once operation. Once it has been performed, the C object is automatically C and can be used to calculate another digest value. =item $md5->hexdigest Same as $md5->digest, but will return the digest in hexadecimal form. =item $md5->b64digest Same as $md5->digest, but will return the digest as a base64 encoded string. =back =head1 EXAMPLES The simplest way to use this library is to import the md5_hex() function (or one of its cousins): use Digest::MD5 qw(md5_hex); print "Digest is ", md5_hex("foobarbaz"), "\n"; The above example would print out the message Digest is 6df23dc03f9b54cc38a0fc1483df6e21 provided that the implementation is working correctly. The same checksum can also be calculated in OO style: use Digest::MD5; $md5 = Digest::MD5->new; $md5->add('foo', 'bar'); $md5->add('baz'); $digest = $md5->hexdigest; print "Digest is $digest\n"; With OO style you can break the message arbitrary. This means that we are no longer limited to have space for the whole message in memory, i.e. we can handle messages of any size. This is useful when calculating checksum for files: use Digest::MD5; my $file = shift || "/etc/passwd"; open(FILE, $file) or die "Can't open '$file': $!"; binmode(FILE); $md5 = Digest::MD5->new; while () { $md5->add($_); } close(FILE); print $md5->b64digest, " $file\n"; Or we can use the builtin addfile method for more efficient reading of the file: use Digest::MD5; my $file = shift || "/etc/passwd"; open(FILE, $file) or die "Can't open '$file': $!"; binmode(FILE); print Digest::MD5->new->addfile(*FILE)->hexdigest, " $file\n"; =head1 SEE ALSO L, L, L, L L RFC 1321 =head1 COPYRIGHT This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. Copyright 1998-2000 Gisle Aas. Copyright 1995-1996 Neil Winton. Copyright 1991-1992 RSA Data Security, Inc. The MD5 algorithm is defined in RFC 1321. The basic C code implementing the algorithm is derived from that in the RFC and is covered by the following copyright: =over 4 =item Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All rights reserved. License to copy and use this software is granted provided that it is identified as the "RSA Data Security, Inc. MD5 Message-Digest Algorithm" in all material mentioning or referencing this software or this function. License is also granted to make and use derivative works provided that such works are identified as "derived from the RSA Data Security, Inc. MD5 Message-Digest Algorithm" in all material mentioning or referencing the derived work. RSA Data Security, Inc. makes no representations concerning either the merchantability of this software or the suitability of this software for any particular purpose. It is provided "as is" without express or implied warranty of any kind. These notices must be retained in any copies of any part of this documentation and/or software. =back This copyright does not prohibit distribution of any version of Perl containing this extension under the terms of the GNU or Artistic licenses. =head1 AUTHORS The original MD5 interface was written by Neil Winton (C). This release was made by Gisle Aas =cut