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package Digest::base; |
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|
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use strict; |
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use vars qw($VERSION); |
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$VERSION = "1.00"; |
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|
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# subclass is supposed to implement at least these |
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sub new; |
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sub clone; |
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sub add; |
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sub digest; |
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|
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sub reset { |
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my $self = shift; |
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$self->new(@_); # ugly |
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} |
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|
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sub addfile { |
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my ($self, $handle) = @_; |
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|
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my $n; |
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my $buf = ""; |
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|
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while (($n = read($handle, $buf, 4*1024))) { |
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$self->add($buf); |
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} |
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unless (defined $n) { |
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require Carp; |
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Carp::croak("Read failed: $!"); |
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} |
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|
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$self; |
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} |
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|
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sub add_bits { |
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my $self = shift; |
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my $bits; |
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my $nbits; |
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if (@_ == 1) { |
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my $arg = shift; |
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$bits = pack("B*", $arg); |
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$nbits = length($arg); |
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} |
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else { |
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($bits, $nbits) = @_; |
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} |
| 47 |
if (($nbits % 8) != 0) { |
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require Carp; |
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Carp::croak("Number of bits must be multiple of 8 for this algorithm"); |
| 50 |
} |
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return $self->add(substr($bits, 0, $nbits/8)); |
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} |
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|
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sub hexdigest { |
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my $self = shift; |
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return unpack("H*", $self->digest(@_)); |
| 57 |
} |
| 58 |
|
| 59 |
sub b64digest { |
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my $self = shift; |
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require MIME::Base64; |
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my $b64 = MIME::Base64::encode($self->digest(@_), ""); |
| 63 |
$b64 =~ s/=+$//; |
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return $b64; |
| 65 |
} |
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|
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1; |
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|
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__END__ |
| 70 |
|
| 71 |
=head1 NAME |
| 72 |
|
| 73 |
Digest::base - Digest base class |
| 74 |
|
| 75 |
=head1 SYNOPSIS |
| 76 |
|
| 77 |
package Digest::Foo; |
| 78 |
use base 'Digest::base'; |
| 79 |
|
| 80 |
=head1 DESCRIPTION |
| 81 |
|
| 82 |
The C<Digest::base> class provide implementations of the methods |
| 83 |
C<addfile> and C<add_bits> in terms of C<add>, and of the methods |
| 84 |
C<hexdigest> and C<b64digest> in terms of C<digest>. |
| 85 |
|
| 86 |
Digest implementations might want to inherit from this class to get |
| 87 |
this implementations of the alternative I<add> and I<digest> methods. |
| 88 |
A minimal subclass needs to implement the following methods by itself: |
| 89 |
|
| 90 |
new |
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clone |
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add |
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digest |
| 94 |
|
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The arguments and expected behaviour of these methods are described in |
| 96 |
L<Digest>. |
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|
| 98 |
=head1 SEE ALSO |
| 99 |
|
| 100 |
L<Digest> |
