[p5sagit/p5-mst-13.2.git] / ext / Digest / MD5 / MD5.pm

package Digest::MD5;

use strict;
use vars qw($VERSION @ISA @EXPORT_OK);

$VERSION = '2.23';  # $Date: 2003/01/19 04:42:15 $

require Exporter;
*import = \&Exporter::import;
@EXPORT_OK = qw(md5 md5_hex md5_base64);

require DynaLoader;
@ISA=qw(DynaLoader);

eval {
    Digest::MD5->bootstrap($VERSION);
};
if ($@) {
    my $olderr = $@;
    eval {
	# 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
    };
    if ($@) {
	# restore the original error
	die $olderr;
    }
}
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<Digest::MD5> 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<Digest::MD5> 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<Digest::MD5>
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.

The base64 encoded string returned is not padded to be a multiple of 4
bytes long.  If you want interoperability with other base64 encoded
md5 digests you might want to append the string "==" to the result.

=back

=head1 METHODS

The following methods are available:

=over 4

=item $md5 = Digest::MD5->new

The constructor returns a new C<Digest::MD5> 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 an 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->clone

This is a copy constructor returning a clone of the $md5 object. It is
useful when you do not want to destroy the digests state, but need an
intermediate value of the digest, e.g. when calculating digests
iteratively on a continuous data stream in order to obtain a copy which
may be destroyed.

=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.

In most cases you want to make sure that the $io_handle is set up to
be in binmode().

=item $md5->digest

Return the binary digest for the message.

Note that the C<digest> operation is effectively a destructive,
read-once operation. Once it has been performed, the C<Digest::MD5>
object is automatically C<reset> and can be used to calculate another
digest value.  Call $md5->clone->digest if you want to calculate the
digest without reseting the digest state.

=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.

The base64 encoded string returned is not padded to be a multiple of 4
bytes long.  If you want interoperability with other base64 encoded
md5 digests you might want to append the string "==" to the result.

=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 (<FILE>) {
        $md5->add($_);
    }
    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";

Perl 5.8 support Unicode characters in strings.  Since the MD5
algorithm is only defined for strings of bytes, it can not be used on
strings that contains chars with ordinal number above 255.  The MD5
functions and methods will croak if you try to feed them such input
data:

    use Digest::MD5 qw(md5_hex);

    my $str = "abc\x{300}";
    print md5_hex($str), "\n";  # croaks
    # Wide character in subroutine entry

What you can do is calculate the MD5 checksum of the UTF-8
representation of such strings.  This is achieved by filtering the
string through encode_utf8() function:

    use Digest::MD5 qw(md5_hex);
    use Encode qw(encode_utf8);

    my $str = "abc\x{300}";
    print md5_hex(encode_utf8($str)), "\n";
    # 8c2d46911f3f5a326455f0ed7a8ed3b3

=head1 SEE ALSO

L<Digest>,
L<Digest::MD2>,
L<Digest::SHA1>,
L<Digest::HMAC>

L<md5sum(1)>

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 1998-2003 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<N.Winton@axion.bt.co.uk>).

This release was made by Gisle Aas <gisle@ActiveState.com>

=cut
Commit	Line	Data
3357b1b1	1	package Digest::MD5;
	2
	3	use strict;
	4	use vars qw($VERSION @ISA @EXPORT_OK);
	5
77e6095e	6	$VERSION = '2.23'; # $Date: 2003/01/19 04:42:15 $
3357b1b1	7
	8	require Exporter;
	9	*import = \&Exporter::import;
	10	@EXPORT_OK = qw(md5 md5_hex md5_base64);
	11
	12	require DynaLoader;
	13	@ISA=qw(DynaLoader);
	14
	15	eval {
	16	Digest::MD5->bootstrap($VERSION);
	17	};
	18	if ($@) {
db2a39d5	19	my $olderr = $@;
	20	eval {
	21	# Try to load the pure perl version
	22	require Digest::Perl::MD5;
	23
	24	Digest::Perl::MD5->import(qw(md5 md5_hex md5_base64));
	25	push(@ISA, "Digest::Perl::MD5"); # make OO interface work
	26	};
	27	if ($@) {
	28	# restore the original error
	29	die $olderr;
	30	}
3357b1b1	31	}
	32	else {
	33	*reset = \&new;
	34	}
	35
	36	1;
	37	__END__
	38
	39	=head1 NAME
	40
	41	Digest::MD5 - Perl interface to the MD5 Algorithm
	42
	43	=head1 SYNOPSIS
	44
	45	# Functional style
	46	use Digest::MD5 qw(md5 md5_hex md5_base64);
	47
	48	$digest = md5($data);
	49	$digest = md5_hex($data);
	50	$digest = md5_base64($data);
	51
	52	# OO style
	53	use Digest::MD5;
	54
	55	$ctx = Digest::MD5->new;
	56
	57	$ctx->add($data);
	58	$ctx->addfile(*FILE);
	59
	60	$digest = $ctx->digest;
	61	$digest = $ctx->hexdigest;
	62	$digest = $ctx->b64digest;
	63
	64	=head1 DESCRIPTION
	65
	66	The C<Digest::MD5> module allows you to use the RSA Data Security
	67	Inc. MD5 Message Digest algorithm from within Perl programs. The
	68	algorithm takes as input a message of arbitrary length and produces as
	69	output a 128-bit "fingerprint" or "message digest" of the input.
	70
	71	The C<Digest::MD5> module provide a procedural interface for simple
	72	use, as well as an object oriented interface that can handle messages
	73	of arbitrary length and which can read files directly.
	74
	75	A binary digest will be 16 bytes long. A hex digest will be 32
	76	characters long. A base64 digest will be 22 characters long.
	77
	78	=head1 FUNCTIONS
	79
	80	The following functions can be exported from the C<Digest::MD5>
	81	module. No functions are exported by default.
	82
	83	=over 4
	84
	85	=item md5($data,...)
	86
	87	This function will concatenate all arguments, calculate the MD5 digest
	88	of this "message", and return it in binary form.
	89
	90	=item md5_hex($data,...)
	91
	92	Same as md5(), but will return the digest in hexadecimal form.
	93
	94	=item md5_base64($data,...)
95
96	Same as md5(), but will return the digest as a base64 encoded string.
97
db2a39d5	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.
	101
3357b1b1	102	=back
	103
	104	=head1 METHODS
	105
	106	The following methods are available:
	107
	108	=over 4
	109
	110	=item $md5 = Digest::MD5->new
	111
	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.
	115
d1be9408	116	If called as an instance method (i.e. $md5->new) it will just reset the
3357b1b1	117	state the object to the state of a newly created object. No new
	118	object is created in this case.
	119
f62a1bde	120	=item $md5->clone
	121
	122	This is a copy constructor returning a clone of the $md5 object. It is
	123	useful when you do not want to destroy the digests state, but need an
	124	intermediate value of the digest, e.g. when calculating digests
	125	iteratively on a continuous data stream in order to obtain a copy which
	126	may be destroyed.
	127
3357b1b1	128	=item $md5->reset
	129
	130	This is just an alias for $md5->new.
	131
	132	=item $md5->add($data,...)
	133
	134	The $data provided as argument are appended to the message we
	135	calculate the digest for. The return value is the $md5 object itself.
	136
	137	=item $md5->addfile($io_handle)
	138
	139	The $io_handle is read until EOF and the content is appended to the
	140	message we calculate the digest for. The return value is the $md5
	141	object itself.
	142
	143	In most cases you want to make sure that the $io_handle is set up to
	144	be in binmode().
	145
	146	=item $md5->digest
	147
	148	Return the binary digest for the message.
	149
	150	Note that the C<digest> operation is effectively a destructive,
	151	read-once operation. Once it has been performed, the C<Digest::MD5>
	152	object is automatically C<reset> and can be used to calculate another
f62a1bde	153	digest value. Call $md5->clone->digest if you want to calculate the
f62a1bde	154	digest without reseting the digest state.
3357b1b1	155
	156	=item $md5->hexdigest
	157
	158	Same as $md5->digest, but will return the digest in hexadecimal form.
	159
	160	=item $md5->b64digest
	161
	162	Same as $md5->digest, but will return the digest as a base64 encoded
	163	string.
	164
db2a39d5	165	The base64 encoded string returned is not padded to be a multiple of 4
	166	bytes long. If you want interoperability with other base64 encoded
	167	md5 digests you might want to append the string "==" to the result.
	168
3357b1b1	169	=back
	170
	171
	172	=head1 EXAMPLES
	173
	174	The simplest way to use this library is to import the md5_hex()
	175	function (or one of its cousins):
	176
	177	use Digest::MD5 qw(md5_hex);
	178	print "Digest is ", md5_hex("foobarbaz"), "\n";
	179
	180	The above example would print out the message
	181
	182	Digest is 6df23dc03f9b54cc38a0fc1483df6e21
	183
	184	provided that the implementation is working correctly. The same
	185	checksum can also be calculated in OO style:
	186
	187	use Digest::MD5;
	188
	189	$md5 = Digest::MD5->new;
	190	$md5->add('foo', 'bar');
	191	$md5->add('baz');
	192	$digest = $md5->hexdigest;
	193
	194	print "Digest is $digest\n";
	195
	196	With OO style you can break the message arbitrary. This means that we
	197	are no longer limited to have space for the whole message in memory, i.e.
	198	we can handle messages of any size.
	199
	200	This is useful when calculating checksum for files:
	201
	202	use Digest::MD5;
	203
	204	my $file = shift \|\| "/etc/passwd";
	205	open(FILE, $file) or die "Can't open '$file': $!";
	206	binmode(FILE);
	207
	208	$md5 = Digest::MD5->new;
	209	while (<FILE>) {
	210	$md5->add($_);
	211	}
	212	close(FILE);
	213	print $md5->b64digest, " $file\n";
	214
	215	Or we can use the builtin addfile method for more efficient reading of
	216	the file:
	217
	218	use Digest::MD5;
	219
	220	my $file = shift \|\| "/etc/passwd";
	221	open(FILE, $file) or die "Can't open '$file': $!";
	222	binmode(FILE);
	223
	224	print Digest::MD5->new->addfile(*FILE)->hexdigest, " $file\n";
	225
9a03235d	226	Perl 5.8 support Unicode characters in strings. Since the MD5
	227	algorithm is only defined for strings of bytes, it can not be used on
	228	strings that contains chars with ordinal number above 255. The MD5
	229	functions and methods will croak if you try to feed them such input
	230	data:
	231
	232	use Digest::MD5 qw(md5_hex);
	233
	234	my $str = "abc\x{300}";
	235	print md5_hex($str), "\n"; # croaks
	236	# Wide character in subroutine entry
	237
	238	What you can do is calculate the MD5 checksum of the UTF-8
	239	representation of such strings. This is achieved by filtering the
	240	string through encode_utf8() function:
	241
	242	use Digest::MD5 qw(md5_hex);
	243	use Encode qw(encode_utf8);
	244
	245	my $str = "abc\x{300}";
	246	print md5_hex(encode_utf8($str)), "\n";
	247	# 8c2d46911f3f5a326455f0ed7a8ed3b3
	248
3357b1b1	249	=head1 SEE ALSO
	250
	251	L<Digest>,
	252	L<Digest::MD2>,
	253	L<Digest::SHA1>,
	254	L<Digest::HMAC>
	255
	256	L<md5sum(1)>
	257
	258	RFC 1321
	259
	260	=head1 COPYRIGHT
	261
	262	This library is free software; you can redistribute it and/or
	263	modify it under the same terms as Perl itself.
	264
f62a1bde	265	Copyright 1998-2003 Gisle Aas.
3357b1b1	266	Copyright 1995-1996 Neil Winton.
	267	Copyright 1991-1992 RSA Data Security, Inc.
	268
	269	The MD5 algorithm is defined in RFC 1321. The basic C code
	270	implementing the algorithm is derived from that in the RFC and is
	271	covered by the following copyright:
	272
	273	=over 4
	274
	275	=item
	276
	277	Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
	278	rights reserved.
	279
	280	License to copy and use this software is granted provided that it
	281	is identified as the "RSA Data Security, Inc. MD5 Message-Digest
	282	Algorithm" in all material mentioning or referencing this software
	283	or this function.
	284
	285	License is also granted to make and use derivative works provided
	286	that such works are identified as "derived from the RSA Data
	287	Security, Inc. MD5 Message-Digest Algorithm" in all material
	288	mentioning or referencing the derived work.
	289
	290	RSA Data Security, Inc. makes no representations concerning either
	291	the merchantability of this software or the suitability of this
	292	software for any particular purpose. It is provided "as is"
	293	without express or implied warranty of any kind.
	294
	295	These notices must be retained in any copies of any part of this
	296	documentation and/or software.
	297
	298	=back
	299
	300	This copyright does not prohibit distribution of any version of Perl
	301	containing this extension under the terms of the GNU or Artistic
	302	licenses.
	303
	304	=head1 AUTHORS
	305
	306	The original MD5 interface was written by Neil Winton
	307	(C<N.Winton@axion.bt.co.uk>).
	308
	309	This release was made by Gisle Aas <gisle@ActiveState.com>
	310
	311	=cut