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Merged
merged 1 commit into from
Nov 13, 2019
Merged

Add bech32 validation for BTC and LTC #11

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129 changes: 129 additions & 0 deletions src/Utils/Bech32Decoder.php
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@@ -0,0 +1,129 @@
<?php

namespace Merkeleon\PhpCryptocurrencyAddressValidation\Utils;

/**
* @see https://github.com/Bit-Wasp/bech32/blob/master/src/bech32.php
*/
class Bech32Decoder
{
const GENERATOR = [0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3];
const CHARKEY_KEY = [
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
15, -1, 10, 17, 21, 20, 26, 30, 7, 5, -1, -1, -1, -1, -1, -1,
-1, 29, -1, 24, 13, 25, 9, 8, 23, -1, 18, 22, 31, 27, 19, -1,
1, 0, 3, 16, 11, 28, 12, 14, 6, 4, 2, -1, -1, -1, -1, -1,
-1, 29, -1, 24, 13, 25, 9, 8, 23, -1, 18, 22, 31, 27, 19, -1,
1, 0, 3, 16, 11, 28, 12, 14, 6, 4, 2, -1, -1, -1, -1, -1
];

/**
* @throws Bech32Exception
* @param string $sBech - the bech32 encoded string
* @return array - returns [$hrp, $dataChars]
*/
static public function decodeRaw($sBech)
{
$length = \strlen($sBech);
if ($length < 8) {
throw new Bech32Exception("Bech32 string is too short");
}
$chars = array_values(unpack('C*', $sBech));
$haveUpper = false;
$haveLower = false;
$positionOne = -1;
for ($i = 0; $i < $length; $i++) {
$x = $chars[$i];
if ($x < 33 || $x > 126) {
throw new Bech32Exception('Out of range character in bech32 string');
}
if ($x >= 0x61 && $x <= 0x7a) {
$haveLower = true;
}
if ($x >= 0x41 && $x <= 0x5a) {
$haveUpper = true;
$x = $chars[$i] = $x + 0x20;
}
// find location of last '1' character
if ($x === 0x31) {
$positionOne = $i;
}
}
if ($haveUpper && $haveLower) {
throw new Bech32Exception('Data contains mixture of higher/lower case characters');
}
if ($positionOne === -1) {
throw new Bech32Exception("Missing separator character");
}
if ($positionOne < 1) {
throw new Bech32Exception("Empty HRP");
}
if (($positionOne + 7) > $length) {
throw new Bech32Exception('Too short checksum');
}
$hrp = \pack("C*", ...\array_slice($chars, 0, $positionOne));
$data = [];
for ($i = $positionOne + 1; $i < $length; $i++) {
$data[] = ($chars[$i] & 0x80) ? -1 : self::CHARKEY_KEY[$chars[$i]];
}
if (!self::verifyChecksum($hrp, $data)) {
throw new Bech32Exception('Invalid bech32 checksum');
}

return [$hrp, array_slice($data, 0, -6)];
}

/**
* Verifies the checksum given $hrp and $convertedDataChars.
*
* @param string $hrp
* @param int[] $convertedDataChars
* @return bool
*/
private static function verifyChecksum($hrp, array $convertedDataChars)
{
$expandHrp = self::hrpExpand($hrp, \strlen($hrp));
$r = \array_merge($expandHrp, $convertedDataChars);
$poly = self::polyMod($r, \count($r));
return $poly === 1;
}

/**
* Expands the human readable part into a character array for checksumming.
* @param string $hrp
* @param int $hrpLen
* @return int[]
*/
private static function hrpExpand($hrp, $hrpLen)
{
$expand1 = [];
$expand2 = [];
for ($i = 0; $i < $hrpLen; $i++) {
$o = \ord($hrp[$i]);
$expand1[] = $o >> 5;
$expand2[] = $o & 31;
}
return \array_merge($expand1, [0], $expand2);
}

/**
* @param int[] $values
* @param int $numValues
* @return int
*/
private static function polyMod(array $values, $numValues)
{
$chk = 1;
for ($i = 0; $i < $numValues; $i++) {
$top = $chk >> 25;
$chk = ($chk & 0x1ffffff) << 5 ^ $values[$i];
for ($j = 0; $j < 5; $j++) {
$value = (($top >> $j) & 1) ? self::GENERATOR[$j] : 0;
$chk ^= $value;
}
}
return $chk;
}
}
8 changes: 8 additions & 0 deletions src/Utils/Bech32Exception.php
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@@ -0,0 +1,8 @@
<?php

namespace Merkeleon\PhpCryptocurrencyAddressValidation\Utils;

class Bech32Exception extends \Exception
{

}
16 changes: 16 additions & 0 deletions src/Validation/BTC.php
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Expand Up @@ -2,6 +2,8 @@

namespace Merkeleon\PhpCryptocurrencyAddressValidation\Validation;

use Merkeleon\PhpCryptocurrencyAddressValidation\Utils\Bech32Decoder;
use Merkeleon\PhpCryptocurrencyAddressValidation\Utils\Bech32Exception;
use Merkeleon\PhpCryptocurrencyAddressValidation\Validation;

class BTC extends Validation
Expand All @@ -11,4 +13,18 @@ class BTC extends Validation
'1' => '00',
'3' => '05'
];

public function validate($address)
{
$valid = parent::validate($address);

if (!$valid) {
// maybe it's a bech32 address
try {
$valid = is_array($decoded = Bech32Decoder::decodeRaw($address)) && 'bc' === $decoded[0];
} catch (Bech32Exception $exception) {}
}

return $valid;
}
}
16 changes: 16 additions & 0 deletions src/Validation/LTC.php
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Expand Up @@ -2,6 +2,8 @@

namespace Merkeleon\PhpCryptocurrencyAddressValidation\Validation;

use Merkeleon\PhpCryptocurrencyAddressValidation\Utils\Bech32Decoder;
use Merkeleon\PhpCryptocurrencyAddressValidation\Utils\Bech32Exception;
use Merkeleon\PhpCryptocurrencyAddressValidation\Validation;

class LTC extends Validation
Expand All @@ -17,6 +19,20 @@ class LTC extends Validation
'3' => '05'
];

public function validate($address)
{
$valid = parent::validate($address);

if (!$valid) {
// maybe it's a bech32 address
try {
$valid = is_array($decoded = Bech32Decoder::decodeRaw($address)) && 'ltc' === $decoded[0];
} catch (Bech32Exception $exception) {}
}

return $valid;
}

protected function validateVersion($version)
{
if (!$this->deprecatedAllowed && in_array($this->addressVersion, self::DEPRECATED_ADDRESS_VERSIONS)) {
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4 changes: 3 additions & 1 deletion tests/BTCTest.php
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Expand Up @@ -14,7 +14,9 @@ public function testValidator()
$testData = [
['1QLbGuc3WGKKKpLs4pBp9H6jiQ2MgPkXRp', true],
['3QJmV3qfvL9SuYo34YihAf3sRCW3qSinyC', true],
['LbTjMGN7gELw4KbeyQf6cTCq859hD18guE', false]
['LbTjMGN7gELw4KbeyQf6cTCq859hD18guE', false],
['bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq', true],
['ltc1qy4rwhdkujk35ga26774gqmng67kgggtqnsx9vp0xgzp3wz3yjkhqashszw', false]
];

foreach ($testData as $row) {
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2 changes: 2 additions & 0 deletions tests/LTCTest.php
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Expand Up @@ -15,6 +15,8 @@ public function testValidator()
['3CDJNfdWX8m2NwuGUV3nhXHXEeLygMXoAj', true],
['LbTjMGN7gELw4KbeyQf6cTCq859hD18guE', true],
['MJRSgZ3UUFcTBTBAaN38XAXvZLwRe8WVw7', true],
['ltc1qy4rwhdkujk35ga26774gqmng67kgggtqnsx9vp0xgzp3wz3yjkhqashszw', true],
['bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq', false]
];

foreach ($testData as $row) {
Expand Down