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@esterTion
Last active February 20, 2024 18:49
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using System;
class LightWeightEncryptor
{
private readonly byte[] swizzleBytes; // 0x10
private readonly int Coef; // 0x18
private readonly int Offset; // 0x1C
public LightWeightEncryptor(uint seed, int initSpin, int tableSize)
{
var xorShift = new XorShift();
xorShift.Init(seed);
if (initSpin >= 1)
{
do
{
xorShift.Next();
--initSpin;
} while (initSpin > 0);
}
swizzleBytes = new byte[tableSize];
xorShift.MakeSwizzleTable(swizzleBytes);
Coef = (int)(xorShift.Next() & 0xF) + 3;
Offset = (int)(xorShift.Next() & 0x1F) + 1;
}
public void Modify(byte[] dataBytes, int offset, int count, long streamOffset, int salt)
{
uint v13 = 0;
uint v14 = (uint)swizzleBytes.Length - 1;
do {
byte v18 = dataBytes[offset + v13];
uint v20 = (uint)(Offset + (streamOffset + offset + salt + v13) * Coef) & v14;
if (v20 >= swizzleBytes.Length)
{
throw new IndexOutOfRangeException();
}
dataBytes[offset + v13] = (byte)(swizzleBytes[v20] ^ v18);
++v13;
} while (count != v13);
}
//public byte[] Transform(byte[] inputBytes, int inputOffset, int inputCount) { }
}
class XorShift
{
private readonly object lockObject; // 0x10
private uint seed; // 0x18
private uint y; // 0x1C
public XorShift() { }
public void Init(uint seed) {
this.seed = seed;
y = seed;
}
public uint Next() {
uint v3 = y ^ (y << 13);
uint v4 = v3 ^ (v3 >> 17) ^ (32 * (v3 ^ (v3 >> 17)));
y = v4;
return v4;
}
public void MakeSwizzleTable(byte[] dest) {
if (dest.Length >= 1)
{
uint v4 = 0;
uint v5 = (uint)dest.Length;
do
{
uint result = this.Next();
dest[v4++] = (byte)((uint)result >> 3);
} while (v5 != v4);
}
}
public static void SwizzleBytes(byte[] target, byte[] swizzle, int coef, int offset, int start) { }
//public int Range(int min, int max) { }
//public float NextFloat() { }
}
<?php
class LightWeightEncryptor {
private $swizzleBytes; // byte[] 0x10
private $Coef = 1; // int 0x18
private $offset = 0; // int 0x1c
function __construct($seed, $initSpin, $tableSize)
{
$XorShift = new XorShift();
$XorShift->Init($seed & 0x7fffffff);
if ($initSpin >= 1) {
do {
$XorShift->Next();
--$initSpin;
} while ($initSpin);
}
$this->swizzleBytes = str_repeat(chr(0), $tableSize);
$XorShift->MakeSwizzleTable($this->swizzleBytes);
$this->Coef = ($XorShift->Next() & 0xf) + 3;
$result = $XorShift->Next();
$this->offset = ($result & 0x1f) + 1;
return $this;
}
function Modify(string &$dataBytes, $offset, $count, $streamOffset, $salt) {
$v13 = 0;
$v14 = strlen($this->swizzleBytes) - 1;
do {
$v20 = ($this->offset + ($streamOffset + $offset + $salt + $v13) * $this->Coef) & $v14;
$dataBytes[$offset + $v13] = $this->swizzleBytes[$v20] ^ $dataBytes[$offset + $v13];
++$v13;
} while ($count != $v13);
}
function Transform($inputBytes, $inputOffset, $inputCount) {
throw new BadMethodCallException();
}
}
class RijndaelEncryptor {
private $key;
private $iv;
private $isDecrypt;
function __construct($pw, $salt, bool $isDecrypt)
{
$rijnIter = 117;
$buf = openssl_pbkdf2($pw, $salt, 32, $rijnIter);
$this->key = substr($buf, 0, 16);
$this->iv = substr($buf, 16, 16);
$this->isDecrypt = $isDecrypt;
}
function Modify(string &$dataBytes, $offset, $count, $streamOffset, $salt) {
throw new BadMethodCallException();
}
function Transform($inputBytes, $inputOffset, $inputCount) {
$data = substr($inputBytes, $inputOffset, $inputCount);
if ($this->isDecrypt) {
return openssl_decrypt($data, 'AES-128-CBC', $this->key, OPENSSL_RAW_DATA+OPENSSL_ZERO_PADDING, $this->iv);
} else {
return openssl_encrypt($data, 'AES-128-CBC', $this->key, OPENSSL_RAW_DATA+OPENSSL_ZERO_PADDING, $this->iv);
}
}
}
class XorShift {
private $lockObject; // object 0x10
private $seed; // uint 0x18
private $y; //uint 0x1c
function __construct()
{
return $this;
}
function Init($seed) {
$this->seed = $seed;
$this->y = $seed;
}
function Next() {
$v3 = $this->y ^ (($this->y << 13) & 0xffffffff);
$v4 = $v3 ^ ($v3 >> 17) ^ (32 * ($v3 ^ ($v3 >> 17))) & 0xffffffff;
$this->y = $v4;
return $v4;
}
function MakeSwizzleTable(string &$dest) {
$v5 = strlen($dest);
if ($v5 >= 1) {
$v4 = 0;
do {
$result = $this->Next();
$dest[$v4++] = chr(($result >> 3) & 0xff);
} while ($v5 != $v4);
}
}
static function SwizzleBytes(&$target, $swizzle, $coef, $offset, $start) {
$count = strlen($target);
if ($count >= 1) {
$mask = strlen($swizzle) - 1;
$k = $count + $start;
for ($i = 0; $i < $count; ) {
$k = ($offset + $k * $coef) & 0xffffffff;
$target[$i] = $target[$i] ^ $swizzle[$k & $mask];
$i++;
}
}
}
function Range($min, $max) {
//
}
function NextFloat() {
//
}
}
@chrrox
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chrrox commented Aug 19, 2021

Nice job.
0x75 CD B2 CF 19 DB 08 3F

0xB5 40 92 3C 7E 45 E8 B2

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