Skip to content

Instantly share code, notes, and snippets.

@carnage carnage/breaker.php Secret
Created Aug 8, 2015

Embed
What would you like to do?
Class which breaks hashids encoding
<?php
class Breaker
{
const ONLY_PRINTABLE = 1;
private $lowerLimit = 0;
private $upperLimit = 256;
public function __construct($flags = 0)
{
if ($flags & self::ONLY_PRINTABLE) {
$this->lowerLimit = 32;
$this->upperLimit = 127;
}
}
private function swap(&$alphabet, $i, $j)
{
$temp = $alphabet[$j];
$alphabet[$j] = $alphabet[$i];
$alphabet[$i] = $temp;
}
private function findNextCharacters(array $salt, $outputIndex, $inputIndex)
{
$t = 0;
foreach ($salt as $s) {
$t = ($t + $s) % $outputIndex;
}
$return = [];
for ($i = $this->lowerLimit; $i < $this->upperLimit; $i++) {
$test = $t + $i+ $i + count($salt);
if (($test % $outputIndex) === $inputIndex) {
$return[] = $i;
}
}
return $return;
}
private function checkSalt(array $salt, $outputIndex, $inputIndex, $length, $debug = false)
{
$t = 0;
$saltIndex = 0;
for ($i = 0; $i < $length; $i++) {
$saltIndex = $i % count($salt);
$t = ($t + $salt[$saltIndex]) % $outputIndex;
}
$t += $salt[$saltIndex] + $saltIndex;
return (($t % $outputIndex) === $inputIndex);
}
public function findSalt($inputString, $outputString, $limit = 10)
{
$initialOutputIndex = strlen($inputString) - 1;
$outputOffset = strlen($inputString) - strlen($outputString);
$iterations = $initialOutputIndex - $outputOffset;
$iterationLimit = $iterations - $limit + $outputOffset;
$inputStringArray = str_split($inputString);
$terminals = [];
$stack = [[]];
$length = 0;
for ($outputIndex = $initialOutputIndex; $outputIndex > $iterationLimit; $outputIndex--) {
$tStart = microtime(true);
$target = array_search($outputString[$outputIndex-$outputOffset], $inputStringArray, true);
$length++;
$terminalsPassed = [];
foreach ($terminals as $key => $test) {
if($this->checkSalt($test, $outputIndex, $target, $length, ($key === 0))) {
$terminalsPassed[] = $test;
}
}
$terminals = $terminalsPassed;
$strings = [];
foreach ($stack as $salt) {
$chars = $this->findNextCharacters($salt, $outputIndex, $target);
foreach ($chars as $char) {
$string = $salt;
$string[] = $char;
$strings[] = $string;
$terminals[] = $string;
}
}
$stack = $strings;
$this->swap($inputStringArray, $target, $outputIndex);
echo sprintf("Loop %d Took: %.2f \n", $length, (microtime(true) - $tStart));
echo sprintf(
"Found %d new candidate salts, confirmed %d previous salts as still possible\n",
count($strings),
count($terminalsPassed)
);
}
}
}
$b = new Breaker(1);
$b->findSalt('abdegjklmnopqrvwxyzABDEGJKLMNOPQRVWXYZ1234567890', 'OXdwnqJxL41r7zAPpbayY290eNv6ZEBVGlgoQjRDMKW5', 20);
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
You can’t perform that action at this time.
You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window. Reload to refresh your session.