<?php
if (class_exists('ParagonIE_Sodium_Core32_ChaCha20', false)) {
return;
}
class ParagonIE_Sodium_Core32_ChaCha20 extends ParagonIE_Sodium_Core32_Util
{
protected static function quarterRound(ParagonIE_Sodium_Core32_Int32 $a, ParagonIE_Sodium_Core32_Int32 $b, ParagonIE_Sodium_Core32_Int32 $c, ParagonIE_Sodium_Core32_Int32 $d)
{
$a = $a->addInt32($b);
$d = $d->xorInt32($a)->rotateLeft(16);
$c = $c->addInt32($d);
$b = $b->xorInt32($c)->rotateLeft(12);
$a = $a->addInt32($b);
$d = $d->xorInt32($a)->rotateLeft(8);
$c = $c->addInt32($d);
$b = $b->xorInt32($c)->rotateLeft(7);
return array($a, $b, $c, $d);
}
public static function encryptBytes(ParagonIE_Sodium_Core32_ChaCha20_Ctx $ctx, $message = '')
{
$bytes = self::strlen($message);
$j0 = $ctx[0];
$j1 = $ctx[1];
$j2 = $ctx[2];
$j3 = $ctx[3];
$j4 = $ctx[4];
$j5 = $ctx[5];
$j6 = $ctx[6];
$j7 = $ctx[7];
$j8 = $ctx[8];
$j9 = $ctx[9];
$j10 = $ctx[10];
$j11 = $ctx[11];
$j12 = $ctx[12];
$j13 = $ctx[13];
$j14 = $ctx[14];
$j15 = $ctx[15];
$c = '';
for (;;) {
if ($bytes < 64) {
$message .= str_repeat("\0", 64 - $bytes);
}
$x0 = clone $j0;
$x1 = clone $j1;
$x2 = clone $j2;
$x3 = clone $j3;
$x4 = clone $j4;
$x5 = clone $j5;
$x6 = clone $j6;
$x7 = clone $j7;
$x8 = clone $j8;
$x9 = clone $j9;
$x10 = clone $j10;
$x11 = clone $j11;
$x12 = clone $j12;
$x13 = clone $j13;
$x14 = clone $j14;
$x15 = clone $j15;
for ($i = 20; $i > 0; $i -= 2) {
list($x0, $x4, $x8, $x12) = self::quarterRound($x0, $x4, $x8, $x12);
list($x1, $x5, $x9, $x13) = self::quarterRound($x1, $x5, $x9, $x13);
list($x2, $x6, $x10, $x14) = self::quarterRound($x2, $x6, $x10, $x14);
list($x3, $x7, $x11, $x15) = self::quarterRound($x3, $x7, $x11, $x15);
list($x0, $x5, $x10, $x15) = self::quarterRound($x0, $x5, $x10, $x15);
list($x1, $x6, $x11, $x12) = self::quarterRound($x1, $x6, $x11, $x12);
list($x2, $x7, $x8, $x13) = self::quarterRound($x2, $x7, $x8, $x13);
list($x3, $x4, $x9, $x14) = self::quarterRound($x3, $x4, $x9, $x14);
}
$x0 = $x0->addInt32($j0);
$x1 = $x1->addInt32($j1);
$x2 = $x2->addInt32($j2);
$x3 = $x3->addInt32($j3);
$x4 = $x4->addInt32($j4);
$x5 = $x5->addInt32($j5);
$x6 = $x6->addInt32($j6);
$x7 = $x7->addInt32($j7);
$x8 = $x8->addInt32($j8);
$x9 = $x9->addInt32($j9);
$x10 = $x10->addInt32($j10);
$x11 = $x11->addInt32($j11);
$x12 = $x12->addInt32($j12);
$x13 = $x13->addInt32($j13);
$x14 = $x14->addInt32($j14);
$x15 = $x15->addInt32($j15);
$x0 = $x0->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 0, 4)));
$x1 = $x1->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 4, 4)));
$x2 = $x2->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 8, 4)));
$x3 = $x3->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 12, 4)));
$x4 = $x4->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 16, 4)));
$x5 = $x5->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 20, 4)));
$x6 = $x6->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 24, 4)));
$x7 = $x7->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 28, 4)));
$x8 = $x8->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 32, 4)));
$x9 = $x9->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 36, 4)));
$x10 = $x10->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 40, 4)));
$x11 = $x11->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 44, 4)));
$x12 = $x12->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 48, 4)));
$x13 = $x13->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 52, 4)));
$x14 = $x14->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 56, 4)));
$x15 = $x15->xorInt32(ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($message, 60, 4)));
$j12 = $j12->addInt(1);
if ($j12->limbs[0] === 0 && $j12->limbs[1] === 0) {
$j13 = $j13->addInt(1);
}
$block = $x0->toReverseString() . $x1->toReverseString() . $x2->toReverseString() . $x3->toReverseString() . $x4->toReverseString() . $x5->toReverseString() . $x6->toReverseString() . $x7->toReverseString() . $x8->toReverseString() . $x9->toReverseString() . $x10->toReverseString() . $x11->toReverseString() . $x12->toReverseString() . $x13->toReverseString() . $x14->toReverseString() . $x15->toReverseString();
if ($bytes < 64) {
$c .= self::substr($block, 0, $bytes);
break;
}
$c .= $block;
$bytes -= 64;
if ($bytes <= 0) {
break;
}
$message = self::substr($message, 64);
}
$ctx[12] = $j12;
$ctx[13] = $j13;
return $c;
}
public static function stream($len = 64, $nonce = '', $key = '')
{
return self::encryptBytes(new ParagonIE_Sodium_Core32_ChaCha20_Ctx($key, $nonce), str_repeat("\0", $len));
}
public static function ietfStream($len, $nonce = '', $key = '')
{
return self::encryptBytes(new ParagonIE_Sodium_Core32_ChaCha20_IetfCtx($key, $nonce), str_repeat("\0", $len));
}
public static function ietfStreamXorIc($message, $nonce = '', $key = '', $ic = '')
{
return self::encryptBytes(new ParagonIE_Sodium_Core32_ChaCha20_IetfCtx($key, $nonce, $ic), $message);
}
public static function streamXorIc($message, $nonce = '', $key = '', $ic = '')
{
return self::encryptBytes(new ParagonIE_Sodium_Core32_ChaCha20_Ctx($key, $nonce, $ic), $message);
}
}