4 use vars qw($VERSION @ISA @EXPORT_OK);
6 $VERSION = '2.16'; # $Date: 2001/09/07 05:45:14 $
9 *import = \&Exporter::import;
10 @EXPORT_OK = qw(md5 md5_hex md5_base64);
16 Digest::MD5->bootstrap($VERSION);
21 # Try to load the pure perl version
22 require Digest::Perl::MD5;
24 Digest::Perl::MD5->import(qw(md5 md5_hex md5_base64));
25 push(@ISA, "Digest::Perl::MD5"); # make OO interface work
28 # restore the original error
41 Digest::MD5 - Perl interface to the MD5 Algorithm
46 use Digest::MD5 qw(md5 md5_hex md5_base64);
49 $digest = md5_hex($data);
50 $digest = md5_base64($data);
55 $ctx = Digest::MD5->new;
60 $digest = $ctx->digest;
61 $digest = $ctx->hexdigest;
62 $digest = $ctx->b64digest;
66 The C<Digest::MD5> module allows you to use the RSA Data Security
67 Inc. MD5 Message Digest algorithm from within Perl programs. The
68 algorithm takes as input a message of arbitrary length and produces as
69 output a 128-bit "fingerprint" or "message digest" of the input.
71 The C<Digest::MD5> module provide a procedural interface for simple
72 use, as well as an object oriented interface that can handle messages
73 of arbitrary length and which can read files directly.
75 A binary digest will be 16 bytes long. A hex digest will be 32
76 characters long. A base64 digest will be 22 characters long.
80 The following functions can be exported from the C<Digest::MD5>
81 module. No functions are exported by default.
87 This function will concatenate all arguments, calculate the MD5 digest
88 of this "message", and return it in binary form.
90 =item md5_hex($data,...)
92 Same as md5(), but will return the digest in hexadecimal form.
94 =item md5_base64($data,...)
96 Same as md5(), but will return the digest as a base64 encoded string.
98 The base64 encoded string returned is not padded to be a multiple of 4
99 bytes long. If you want interoperability with other base64 encoded
100 md5 digests you might want to append the string "==" to the result.
106 The following methods are available:
110 =item $md5 = Digest::MD5->new
112 The constructor returns a new C<Digest::MD5> object which encapsulate
113 the state of the MD5 message-digest algorithm. You can add data to
114 the object and finally ask for the digest.
116 If called as an instance method (i.e. $md5->new) it will just reset the
117 state the object to the state of a newly created object. No new
118 object is created in this case.
122 This is just an alias for $md5->new.
124 =item $md5->add($data,...)
126 The $data provided as argument are appended to the message we
127 calculate the digest for. The return value is the $md5 object itself.
129 =item $md5->addfile($io_handle)
131 The $io_handle is read until EOF and the content is appended to the
132 message we calculate the digest for. The return value is the $md5
135 In most cases you want to make sure that the $io_handle is set up to
140 Return the binary digest for the message.
142 Note that the C<digest> operation is effectively a destructive,
143 read-once operation. Once it has been performed, the C<Digest::MD5>
144 object is automatically C<reset> and can be used to calculate another
147 =item $md5->hexdigest
149 Same as $md5->digest, but will return the digest in hexadecimal form.
151 =item $md5->b64digest
153 Same as $md5->digest, but will return the digest as a base64 encoded
156 The base64 encoded string returned is not padded to be a multiple of 4
157 bytes long. If you want interoperability with other base64 encoded
158 md5 digests you might want to append the string "==" to the result.
165 The simplest way to use this library is to import the md5_hex()
166 function (or one of its cousins):
168 use Digest::MD5 qw(md5_hex);
169 print "Digest is ", md5_hex("foobarbaz"), "\n";
171 The above example would print out the message
173 Digest is 6df23dc03f9b54cc38a0fc1483df6e21
175 provided that the implementation is working correctly. The same
176 checksum can also be calculated in OO style:
180 $md5 = Digest::MD5->new;
181 $md5->add('foo', 'bar');
183 $digest = $md5->hexdigest;
185 print "Digest is $digest\n";
187 With OO style you can break the message arbitrary. This means that we
188 are no longer limited to have space for the whole message in memory, i.e.
189 we can handle messages of any size.
191 This is useful when calculating checksum for files:
195 my $file = shift || "/etc/passwd";
196 open(FILE, $file) or die "Can't open '$file': $!";
199 $md5 = Digest::MD5->new;
204 print $md5->b64digest, " $file\n";
206 Or we can use the builtin addfile method for more efficient reading of
211 my $file = shift || "/etc/passwd";
212 open(FILE, $file) or die "Can't open '$file': $!";
215 print Digest::MD5->new->addfile(*FILE)->hexdigest, " $file\n";
230 This library is free software; you can redistribute it and/or
231 modify it under the same terms as Perl itself.
233 Copyright 1998-2001 Gisle Aas.
234 Copyright 1995-1996 Neil Winton.
235 Copyright 1991-1992 RSA Data Security, Inc.
237 The MD5 algorithm is defined in RFC 1321. The basic C code
238 implementing the algorithm is derived from that in the RFC and is
239 covered by the following copyright:
245 Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
248 License to copy and use this software is granted provided that it
249 is identified as the "RSA Data Security, Inc. MD5 Message-Digest
250 Algorithm" in all material mentioning or referencing this software
253 License is also granted to make and use derivative works provided
254 that such works are identified as "derived from the RSA Data
255 Security, Inc. MD5 Message-Digest Algorithm" in all material
256 mentioning or referencing the derived work.
258 RSA Data Security, Inc. makes no representations concerning either
259 the merchantability of this software or the suitability of this
260 software for any particular purpose. It is provided "as is"
261 without express or implied warranty of any kind.
263 These notices must be retained in any copies of any part of this
264 documentation and/or software.
268 This copyright does not prohibit distribution of any version of Perl
269 containing this extension under the terms of the GNU or Artistic
274 The original MD5 interface was written by Neil Winton
275 (C<N.Winton@axion.bt.co.uk>).
277 This release was made by Gisle Aas <gisle@ActiveState.com>