| Subject: | API Non-Conformance and pseudo-random behavior |
I have experienced multiple disorders with whirlpool, some of which I've
had trouble to classify and test for.
I believe I have 2 that I can however test for, that are likely to share
the same cause.
1. Calling ->hexdigest does not reset the state to empty.
2. Calling ->hexdigest multiple times without manually resetting the
state causes different values to be emitted without adding new data.
I have not been able to think of a good way to write a Test::More test
that exhibits the behaviour I'm experiencing, but I have however
produced a way to compare Whirlpools behaviour with MD5 as a standard.
the behaviours are drastically different.
http://gist.github.com/212780
This GIST contains
1. Output from my test script, showing how different the values are, esp
with regard to using MD5 as the standard.
2. The test script.
3. Valgrind output
4. Selected output from valgrind.
I note there are a few memory leaks that valgrind discovers in Whirlpool
itself, but how significant this is I don't know. ( Its been too long
since I last coded in C, and really not looking forward to going back ).
NB: Only the example script has been attached to this bug report to
reduce mental load for all.
All the best.
| Subject: | self_changing_state.pl |
#!/usr/bin/perl
use strict;
use warnings;
use Digest::Whirlpool;
use Digest::MD5;
use Data::Dump qw( dump );
my @digesters;
for ( 1..5 ){
push @digesters, { whirlpool => Digest::Whirlpool->new(), md5 => Digest::MD5->new() };
}
# seeing that its constant accross instances.
for ( @digesters ) {
print "Whirlpool: \n";
my $hex = $_->{whirlpool}->hexdigest();
my $hexd = $_->{whirlpool}->hexdigest();
if( $hex ne $hexd ){
print "left ne right, but no input has been added\n";
print "left: $hex\n";
print "right: $hexd\n";
} else {
print "left eq right\n";
}
print "MD5: \n";
$hex = $_->{md5}->hexdigest();
$hexd = $_->{md5}->hexdigest();
if( $hex ne $hexd ){
print "left ne right, but no input has been added\n";
print "left: $hex\n";
print "right: $hexd\n";
} else {
print "left eq right\n";
}
print "\n";
}
# seeing that within a single digester, the same empty value results in a pseudorandom sequence generation.
$digesters[0]->{whirlpool}->reset();
$digesters[0]->{md5}->reset();
for ( 1..10 ){
print "whirlpool $_ : " . $digesters[0]->{whirlpool}->hexdigest . "\n";
}
for ( 1..10 ){
print "md5 $_ : " . $digesters[0]->{md5}->hexdigest . "\n";
}
# seeing that the digester doesn't conform to the specification that the rest conform to
# with regard to hexdigest resetting the state.
print "\n";
$digesters[0]->{whirlpool}->reset();
for ( 1..10 ){
$digesters[0]->{whirlpool}->add('hello');
print "whirlpool $_ : " . $digesters[0]->{whirlpool}->hexdigest . "\n";
}
for ( 1..10 ){
$digesters[0]->{md5}->add('hello');
print "md5 $_ : " . $digesters[0]->{md5}->hexdigest . "\n";
}