Clash Royale CLAN TAG#URR8PPP

Perl SHA-256 algorithm generates output different from the equivalent Java

I have the following Java code:

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;

public class MyClass

public static void main(String args)

byte salt =
84, 65, -51, 83, -4, -17, -32, 61,
-26, 33, -106, -81, -14, 70, -30, 59,
41, -19, -1, 19, -104, -100, -31, 31,
57, -6, -115, -99, 0, 38, -123, -11
;

byte password = 100, 112, 107, 57, 52, 110, 50 ;

try

MessageDigest messageDigest;

messageDigest = MessageDigest.getInstance("SHA-256");

messageDigest.reset();
messageDigest.update(salt);

byte hash = messageDigest.digest(password);

for (int i = 1; i < 1000; i++)

messageDigest.reset();
hash = messageDigest.digest(hash);


StringBuffer stringBuffer = new StringBuffer(hash.length * 2);

for (int i = 0; i < hash.length; i++)

stringBuffer.append(Character.forDigit(hash[i] >> 4 & 0xF, 16));
stringBuffer.append(Character.forDigit(hash[i] & 0xF, 16));


System.out.println("HashArray: " + Arrays.toString(hash));
System.out.println("HashString: " + stringBuffer.toString());

catch (NoSuchAlgorithmException e)
e.printStackTrace();





The output is

HashArray: [-127, -38, -46, -2, 51, -2, -83, -42, 3, 83, -78, -72, -115, -28, 108, 58, -76, -35, -13, 33, 63, -96, 104, 101, -76, 23, 102, -28, -60, 4, 85, 82]


and

HashString: 81dad2fe33feadd60353b2b88de46c3ab4ddf3213fa06865b41766e4c4045552


I tried to translate the Java code to Perl, but I have a understanding problem. In Java, I use two arrays to generate the hash. If I use the same arrays in Perl, I don't get the same result.

Here is my Perl code:

use strict;
use warnings;

use Digest::SHA 'sha256';

my @salt = (
"84", "65", -"51", "83", "-4", "-17", "-32", "61",
"-26", "33", "-106", "-81", "-14", "70", "-30", "59",
"41", "-19", "-1", "19", "-104", "-100", "-31", "31",
"57", "-6", "-115", "-99", "0", "38", "-123", "-11"
);

my @password = ( "100", "112", "107", "57", "52", "110", "50" );

my $alg = 256;
my $sha = Digest::SHA->new($alg);

$sha->add(@salt);
$sha->add(@password);

for ( my $i = 1; $i < 1000; $i++ )
$sha->add(@password)


my $output = $sha->hexdigest;
print "nHash: $outputn";


Output is

Hash: 3883ae8f7438cc7e8fac86d25aa5789c4434294a70ea13d5e8f547fc7a8e45c2


Can someone explain how to get the Perl code to produce the same output as the Java?

-"51"

"-51"

1 Answer
1

Two problems:

The Java version works with bytes, the Perl version with strings of digits. Use pack to convert the strings to their byte equivalents.

In the Java version, you are applying the hash to the hash computed so far, in the Perl code, you just hash the same value again and again.

#!/usr/bin/perl
use warnings;
use strict;

use Digest::SHA 'sha256';

my @salt = (84, 65, -51, 83, -4, -17, -32, 61, -26, 33, -106, -81,
-14, 70, -30, 59, 41, -19, -1, 19, -104, -100, -31, 31,
57, -6, -115, -99, 0, 38, -123, -11);

my @password = (100, 112, 107, 57, 52, 110, 50);

my $alg = 256;
my $sha = Digest::SHA->new($alg);

$sha->add(pack 'c*', @salt);
$sha->add(pack 'c*', @password);

$sha->add($sha->digest) for 1 .. 999;

my $output = $sha->hexdigest;
print "nHash: $outputn";


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