<?php
if (class_exists('ParagonIE_Sodium_Core_ChaCha20', false)) {
return;
}
/**
* Class ParagonIE_Sodium_Core_ChaCha20
*/
class ParagonIE_Sodium_Core_ChaCha20 extends ParagonIE_Sodium_Core_Util
{
/**
* Bitwise left rotation
*
* @internal You should not use this directly from another application
*
* @param int $v
* @param int $n
* @return int
*/
public static function rotate($v, $n)
{
$v &= 0xffffffff;
$n &= 31;
return (int) (
0xffffffff & (
($v << $n)
|
($v >> (32 - $n))
)
);
}
/**
* The ChaCha20 quarter round function. Works on four 32-bit integers.
*
* @internal You should not use this directly from another application
*
* @param int $a
* @param int $b
* @param int $c
* @param int $d
* @return array<int, int>
*/
protected static function quarterRound($a, $b, $c, $d)
{
# a = PLUS(a,b); d = ROTATE(XOR(d,a),16);
/** @var int $a */
$a = ($a + $b) & 0xffffffff;
$d = self::rotate($d ^ $a, 16);
# c = PLUS(c,d); b = ROTATE(XOR(b,c),12);
/** @var int $c */
$c = ($c + $d) & 0xffffffff;
$b = self::rotate($b ^ $c, 12);
# a = PLUS(a,b); d = ROTATE(XOR(d,a), 8);
/** @var int $a */
$a = ($a + $b) & 0xffffffff;
$d = self::rotate($d ^ $a, 8);
# c = PLUS(c,d); b = ROTATE(XOR(b,c), 7);
/** @var int $c */
$c = ($c + $d) & 0xffffffff;
$b = self::rotate($b ^ $c, 7);
return array((int) $a, (int) $b, (int) $c, (int) $d);
}
/**
* @internal You should not use this directly from another application
*
* @param ParagonIE_Sodium_Core_ChaCha20_Ctx $ctx
* @param string $message
*
* @return string
* @throws TypeError
* @throws SodiumException
*/
public static function encryptBytes(
ParagonIE_Sodium_Core_ChaCha20_Ctx $ctx,
$message = ''
) {
$bytes = self::strlen($message);
/*
j0 = ctx->input[0];
j1 = ctx->input[1];
j2 = ctx->input[2];
j3 = ctx->input[3];
j4 = ctx->input[4];
j5 = ctx->input[5];
j6 = ctx->input[6];
j7 = ctx->input[7];
j8 = ctx->input[8];
j9 = ctx->input[9];
j10 = ctx->input[10];
j11 = ctx->input[11];
j12 = ctx->input[12];
j13 = ctx->input[13];
j14 = ctx->input[14];
j15 = ctx->input[15];
*/
$j0 = (int) $ctx[0];
$j1 = (int) $ctx[1];
$j2 = (int) $ctx[2];
$j3 = (int) $ctx[3];
$j4 = (int) $ctx[4];
$j5 = (int) $ctx[5];
$j6 = (int) $ctx[6];
$j7 = (int) $ctx[7];
$j8 = (int) $ctx[8];
$j9 = (int) $ctx[9];
$j10 = (int) $ctx[10];
$j11 = (int) $ctx[11];
$j12 = (int) $ctx[12];
$j13 = (int) $ctx[13];
$j14 = (int) $ctx[14];
$j15 = (int) $ctx[15];
$c = '';
for (;;) {
if ($bytes < 64) {
$message .= str_repeat("\x00", 64 - $bytes);
}
$x0 = (int) $j0;
$x1 = (int) $j1;
$x2 = (int) $j2;
$x3 = (int) $j3;
$x4 = (int) $j4;
$x5 = (int) $j5;
$x6 = (int) $j6;
$x7 = (int) $j7;
$x8 = (int) $j8;
$x9 = (int) $j9;
$x10 = (int) $j10;
$x11 = (int) $j11;
$x12 = (int) $j12;
$x13 = (int) $j13;
$x14 = (int) $j14;
$x15 = (int) $j15;
# for (i = 20; i > 0; i -= 2) {
for ($i = 20; $i > 0; $i -= 2) {
# QUARTERROUND( x0, x4, x8, x12)
list($x0, $x4, $x8, $x12) = self::quarterRound($x0, $x4, $x8, $x12);
# QUARTERROUND( x1, x5, x9, x13)
list($x1, $x5, $x9, $x13) = self::quarterRound($x1, $x5, $x9, $x13);
# QUARTERROUND( x2, x6, x10, x14)
list($x2, $x6, $x10, $x14) = self::quarterRound($x2, $x6, $x10, $x14);
# QUARTERROUND( x3, x7, x11, x15)
list($x3, $x7, $x11, $x15) = self::quarterRound($x3, $x7, $x11, $x15);
# QUARTERROUND( x0, x5, x10, x15)
list($x0, $x5, $x10, $x15) = self::quarterRound($x0, $x5, $x10, $x15);
# QUARTERROUND( x1, x6, x11, x12)
list($x1, $x6, $x11, $x12) = self::quarterRound($x1, $x6, $x11, $x12);
# QUARTERROUND( x2, x7, x8, x13)
list($x2, $x7, $x8, $x13) = self::quarterRound($x2, $x7, $x8, $x13);
# QUARTERROUND( x3, x4, x9, x14)
list($x3, $x4, $x9, $x14) = self::quarterRound($x3, $x4, $x9, $x14);
}
/*
x0 = PLUS(x0, j0);
x1 = PLUS(x1, j1);
x2 = PLUS(x2, j2);
x3 = PLUS(x3, j3);
x4 = PLUS(x4, j4);
x5 = PLUS(x5, j5);
x6 = PLUS(x6, j6);
x7 = PLUS(x7, j7);
x8 = PLUS(x8, j8);
x9 = PLUS(x9, j9);
x10 = PLUS(x10, j10);
x11 = PLUS(x11, j11);
x12 = PLUS(x12, j12);
x13 = PLUS(x13, j13);
x14 = PLUS(x14, j14);
x15 = PLUS(x15, j15);
*/
/** @var int $x0 */
$x0 = ($x0 & 0xffffffff) + $j0;
/** @var int $x1 */
$x1 = ($x1 & 0xffffffff) + $j1;
/** @var int $x2 */
$x2 = ($x2 & 0xffffffff) + $j2;
/** @var int $x3 */
$x3 = ($x3 & 0xffffffff) + $j3;
/** @var int $x4 */
$x4 = ($x4 & 0xffffffff) + $j4;
/** @var int $x5 */
$x5 = ($x5 & 0xffffffff) + $j5;
/** @var int $x6 */
$x6 = ($x6 & 0xffffffff) + $j6;
/** @var int $x7 */
$x7 = ($x7 & 0xffffffff) + $j7;
/** @var int $x8 */
$x8 = ($x8 & 0xffffffff) + $j8;
/** @var int $x9 */
$x9 = ($x9 & 0xffffffff) + $j9;
/** @var int $x10 */
$x10 = ($x10 & 0xffffffff) + $j10;
/** @var int $x11 */
$x11 = ($x11 & 0xffffffff) + $j11;
/** @var int $x12 */
$x12 = ($x12 & 0xffffffff) + $j12;
/** @var int $x13 */
$x13 = ($x13 & 0xffffffff) + $j13;
/** @var int $x14 */
$x14 = ($x14 & 0xffffffff) + $j14;
/** @var int $x15 */
$x15 = ($x15 & 0xffffffff) + $j15;
/*
x0 = XOR(x0, LOAD32_LE(m + 0));
x1 = XOR(x1, LOAD32_LE(m + 4));
x2 = XOR(x2, LOAD32_LE(m + 8));
x3 = XOR(x3, LOAD32_LE(m + 12));
x4 = XOR(x4, LOAD32_LE(m + 16));
x5 = XOR(x5, LOAD32_LE(m + 20));
x6 = XOR(x6, LOAD32_LE(m + 24));
x7 = XOR(x7, LOAD32_LE(m + 28));
x8 = XOR(x8, LOAD32_LE(m + 32));
x9 = XOR(x9, LOAD32_LE(m + 36));
x10 = XOR(x10, LOAD32_LE(m + 40));
x11 = XOR(x11, LOAD32_LE(m + 44));
x12 = XOR(x12, LOAD32_LE(m + 48));
x13 = XOR(x13, LOAD32_LE(m + 52));
x14 = XOR(x14, LOAD32_LE(m + 56));
x15 = XOR(x15, LOAD32_LE(m + 60));
*/
$x0 ^= self::load_4(self::substr($message, 0, 4));
$x1 ^= self::load_4(self::substr($message, 4, 4));
$x2 ^= self::load_4(self::substr($message, 8, 4));
$x3 ^= self::load_4(self::substr($message, 12, 4));
$x4 ^= self::load_4(self::substr($message, 16, 4));
$x5 ^= self::load_4(self::substr($message, 20, 4));
$x6 ^= self::load_4(self::substr($message, 24, 4));
$x7 ^= self::load_4(self::substr($message, 28, 4));
$x8 ^= self::load_4(self::substr($message, 32, 4));
$x9 ^= self::load_4(self::substr($message, 36, 4));
$x10 ^= self::load_4(self::substr($message, 40, 4));
$x11 ^= self::load_4(self::substr($message, 44, 4));
$x12 ^= self::load_4(self::substr($message, 48, 4));
$x13 ^= self::load_4(self::substr($message, 52, 4));
$x14 ^= self::load_4(self::substr($message, 56, 4));
$x15 ^= self::load_4(self::substr($message, 60, 4));
/*
j12 = PLUSONE(j12);
if (!j12) {
j13 = PLUSONE(j13);
}
*/
++$j12;
if ($j12 & 0xf0000000) {
throw new SodiumException('Overflow');
}
/*
STORE32_LE(c + 0, x0);
STORE32_LE(c + 4, x1);
STORE32_LE(c + 8, x2);
STORE32_LE(c + 12, x3);
STORE32_LE(c + 16, x4);
STORE32_LE(c + 20, x5);
STORE32_LE(c + 24, x6);
STORE32_LE(c + 28, x7);
STORE32_LE(c + 32, x8);
STORE32_LE(c + 36, x9);
STORE32_LE(c + 40, x10);
STORE32_LE(c + 44, x11);
STORE32_LE(c + 48, x12);
STORE32_LE(c + 52, x13);
STORE32_LE(c + 56, x14);
STORE32_LE(c + 60, x15);
*/
$block = self::store32_le((int) ($x0 & 0xffffffff)) .
self::store32_le((int) ($x1 & 0xffffffff)) .
self::store32_le((int) ($x2 & 0xffffffff)) .
self::store32_le((int) ($x3 & 0xffffffff)) .
self::store32_le((int) ($x4 & 0xffffffff)) .
self::store32_le((int) ($x5 & 0xffffffff)) .
self::store32_le((int) ($x6 & 0xffffffff)) .
self::store32_le((int) ($x7 & 0xffffffff)) .
self::store32_le((int) ($x8 & 0xffffffff)) .
self::store32_le((int) ($x9 & 0xffffffff)) .
self::store32_le((int) ($x10 & 0xffffffff)) .
self::store32_le((int) ($x11 & 0xffffffff)) .
self::store32_le((int) ($x12 & 0xffffffff)) .
self::store32_le((int) ($x13 & 0xffffffff)) .
self::store32_le((int) ($x14 & 0xffffffff)) .
self::store32_le((int) ($x15 & 0xffffffff));
/* Partial block */
if ($bytes < 64) {
$c .= self::substr($block, 0, $bytes);
break;
}
/* Full block */
$c .= $block;
$bytes -= 64;
if ($bytes <= 0) {
break;
}
$message = self::substr($message, 64);
}
/* end for(;;) loop */
$ctx[12] = $j12;
$ctx[13] = $j13;
return $c;
}
/**
* @internal You should not use this directly from another application
*
* @param int $len
* @param string $nonce
* @param string $key
* @return string
* @throws SodiumException
* @throws TypeError
*/
public static function stream($len = 64, $nonce = '', $key = '')
{
return self::encryptBytes(
new ParagonIE_Sodium_Core_ChaCha20_Ctx($key, $nonce),
str_repeat("\x00", $len)
);
}
/**
* @internal You should not use this directly from another application
*
* @param int $len
* @param string $nonce
* @param string $key
* @return string
* @throws SodiumException
* @throws TypeError
*/
public static function ietfStream($len, $nonce = '', $key = '')
{
return self::encryptBytes(
new ParagonIE_Sodium_Core_ChaCha20_IetfCtx($key, $nonce),
str_repeat("\x00", $len)
);
}
/**
* @internal You should not use this directly from another application
*
* @param string $message
* @param string $nonce
* @param string $key
* @param string $ic
* @return string
* @throws SodiumException
* @throws TypeError
*/
public static function ietfStreamXorIc($message, $nonce = '', $key = '', $ic = '')
{
return self::encryptBytes(
new ParagonIE_Sodium_Core_ChaCha20_IetfCtx($key, $nonce, $ic),
$message
);
}
/**
* @internal You should not use this directly from another application
*
* @param string $message
* @param string $nonce
* @param string $key
* @param string $ic
* @return string
* @throws SodiumException
* @throws TypeError
*/
public static function streamXorIc($message, $nonce = '', $key = '', $ic = '')
{
return self::encryptBytes(
new ParagonIE_Sodium_Core_ChaCha20_Ctx($key, $nonce, $ic),
$message
);
}
}