Skip to content

Add support for eCash address #8

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
Fabcien wants to merge 1 commit into
base: master
Choose a base branch
from
Open

Add support for eCash address #8

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
250 changes: 222 additions & 28 deletions CashAddress.php
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -125,10 +125,12 @@ class CashAddress {
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -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];
const EXPAND_PREFIX_UNPROCESSED = [2, 9, 20, 3, 15, 9, 14, 3, 1, 19, 8, 0];
const EXPAND_PREFIX_TESTNET_UNPROCESSED = [2, 3, 8, 20, 5, 19, 20, 0];
const EXPAND_PREFIX = 1058337025301;
const EXPAND_PREFIX_TESTNET = 584719417569;
const BCH_EXPAND_PREFIX_UNPROCESSED = [2, 9, 20, 3, 15, 9, 14, 3, 1, 19, 8, 0];
const BCH_EXPAND_PREFIX_TESTNET_UNPROCESSED = [2, 3, 8, 20, 5, 19, 20, 0];
const BCH_EXPAND_PREFIX = 1058337025301;
const BCH_EXPAND_PREFIX_TESTNET = 584719417569;
const ECASH_EXPAND_PREFIX_UNPROCESSED = [5, 3, 1, 19, 8, 0];
const ECASH_EXPAND_PREFIX_TESTNET_UNPROCESSED = [5, 3, 20, 5, 19, 20, 0];
const BASE16 = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -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, 10, 11, 12,
Expand Down Expand Up @@ -351,10 +353,10 @@ static public function old2new($oldAddress)
$payloadConverted = self::convertBits($data, 8, 5, true);
$arr = array_merge($payloadConverted, [0, 0, 0, 0, 0, 0, 0, 0]);
if ($realNet) {
$expand_prefix = self::EXPAND_PREFIX;
$expand_prefix = self::BCH_EXPAND_PREFIX;
$ret = 'bitcoincash:';
} else {
$expand_prefix = self::EXPAND_PREFIX_TESTNET;
$expand_prefix = self::BCH_EXPAND_PREFIX_TESTNET;
$ret = 'bchtest:';
}
$mod = self::polymod($arr, $expand_prefix);
Expand All @@ -368,11 +370,7 @@ static public function old2new($oldAddress)
}

$combined = array_merge($payloadConverted, $checksum);
$combined_len = sizeof($combined);
for ($i = 0; $i < $combined_len; $i++)
{
$ret .= self::CHARSET[$combined[$i]];
}
$ret .= self::bechEncode($combined);

return $ret;
}
Expand All @@ -392,46 +390,36 @@ static public function decodeNewAddr($inputNew, $shouldFixErrors, &$isTestnetAdd
$inputNew = strtolower($inputNew);
if (strpos($inputNew, ':') === false) {
$afterPrefix = 0;
$expand_prefix = self::EXPAND_PREFIX;
$expand_prefix = self::BCH_EXPAND_PREFIX;
$isTestnetAddressResult = false;
}
else if (substr($inputNew, 0, 12) === 'bitcoincash:')
{
$afterPrefix = 12;
$expand_prefix = self::EXPAND_PREFIX;
$expand_prefix = self::BCH_EXPAND_PREFIX;
$isTestnetAddressResult = false;
}
else if (substr($inputNew, 0, 8) === 'bchtest:')
{
$afterPrefix = 8;
$expand_prefix = self::EXPAND_PREFIX_TESTNET;
$expand_prefix = self::BCH_EXPAND_PREFIX_TESTNET;
$isTestnetAddressResult = true;
}
else
{
throw new CashAddressException('Unknown address type');
}

$data = [];
$len = strlen($inputNew);
for (; $afterPrefix < $len; $afterPrefix++)
{
$i = ord($inputNew[$afterPrefix]);
if ($i > 127 || (($i = self::BECH_ALPHABET[$i]) === -1))
{
throw new CashAddressException('Unexpected character in address!');
}
array_push($data, $i);
}
$data = self::bechDecode(substr($inputNew, $afterPrefix));

$checksum = self::polyMod($data, $expand_prefix);

if ($checksum !== 0)
{
if ($expand_prefix === self::EXPAND_PREFIX_TESTNET) {
$unexpand_prefix = self::EXPAND_PREFIX_TESTNET_UNPROCESSED;
if ($expand_prefix === self::BCH_EXPAND_PREFIX_TESTNET) {
$unexpand_prefix = self::BCH_EXPAND_PREFIX_TESTNET_UNPROCESSED;
} else {
$unexpand_prefix = self::EXPAND_PREFIX_UNPROCESSED;
$unexpand_prefix = self::BCH_EXPAND_PREFIX_UNPROCESSED;
}
// Checksum is wrong!
// Try to fix up to two errors
Expand Down Expand Up @@ -603,6 +591,212 @@ private static function doubleSha256ByteArray($byteArray) {
}
return $hashArray;
}

/**
* Internal function to decode a Bech32 encoded address.
* @param string $address The address to be decoded
* @return array $addressData The decoded address data
*/
private static function bechDecode($address) {
$addressData = [];
$len = strlen($address);
for ($pos = 0; $pos < $len; $pos++)
{
$i = ord($address[$pos]);
if ($i > 127 || (($i = self::BECH_ALPHABET[$i]) === -1))
{
throw new CashAddressException('Unexpected character in address!');
}
array_push($addressData, $i);
}

return $addressData;
}

/**
* Internal function to encode cash address data using Bech32 encoding.
* @param array $addressData The address data to encode
* @return string $address The encoded address
*/
private static function bechEncode($addressData) {
$address = '';
$data_len = sizeof($addressData);

for ($i = 0; $i < $data_len; $i++)
{
$address .= self::CHARSET[$addressData[$i]];
}

return $address;
}

/**
* Internal function to check if the given prefix matches the address
* @param string $prefix The prefix to check the address against
* @param string $addressNoPrefix The address and checksum without the
* prefix
* @return bool $prefixMatch True if the prefix matches the address
*/
private static function checkPrefix($prefixData, $addressNoPrefix) {
$addressData = self::bechDecode($addressNoPrefix);
return self::polymod(array_merge($prefixData, $addressData)) === 0;
}

/**
* Attempt to retrieve the prefix from an address. Throws on failure.
* @param string $addressNoPrefix The address and checksum without the
* prefix
* @return string $prefix The address prefix
*/
public static function getPrefix($addressNoPrefix)
{
$prefixDatas = [
'bitcoincash' => self::BCH_EXPAND_PREFIX_UNPROCESSED,
'ecash' => self::ECASH_EXPAND_PREFIX_UNPROCESSED,
'bchtest' => self::BCH_EXPAND_PREFIX_TESTNET_UNPROCESSED,
'ectest' => self::ECASH_EXPAND_PREFIX_TESTNET_UNPROCESSED,
];
foreach ($prefixDatas as $prefix => $prefixData)
{
if (self::checkPrefix($prefixData, $addressNoPrefix) === True)
{
return $prefix;
}
}

throw new CashAddressException('Cannot determine the prefix for the cash address: ' . $addressNoPrefix . '!');
return "unknown";
}

/**
* Internal function to convert the output of the polymod computation to a
* properly formatted cash address checksum.
* @param string $polymod The computed polymod value
* @return array $checksum The properly formatted checksum
*/
private static function checksum($polymod)
{
$checksum = [0, 0, 0, 0, 0, 0, 0, 0];

for ($i = 0; $i < 8; $i++)
{
// Convert the 5-bit groups in mod to checksum values.
// $checksum[$i] = ($mod >> 5*(7-$i)) & 0x1f;
$checksum[$i] = ($polymod >> (5 * (7 - $i))) & 0x1f;
}

return $checksum;
}

/**
* Internal function to build a cash address from the prefix and address.
* The address is expected to contain a checksum but might not match the
* prefix. The checksum of the output address is recomputed to match the
* given prefix.
* @param string $prefix The prefix to use for building the cash address
* @param array $prefixData The prefix formatted as the 5 lsb for each byte
* plus a trailing 0
* @param string $addressNoPrefix The address and checksum without the
* prefix
* @return string $address The new cash address
*/
private static function buildCashAddress($prefix, $prefixData, $addressNoPrefix)
{
$payload = self::bechDecode(substr($addressNoPrefix, 0, -8));

$mod = self::polymod(array_merge($prefixData, $payload, [0, 0, 0, 0, 0, 0, 0, 0]));

$addressData = array_merge($payload, self::checksum($mod));

return $prefix . ':' . self::bechEncode($addressData);
}

/**
* Internal function to split a cash address parts. If the input address has
no prefix, it is determined from the remaining of the address.
* @param string $address The cash address to split
* @return array $parts An array containg the prefix and the address content
*/
static private function splitCashAddress($address)
{
$parts = explode(':', $address);

$addressNoPrefix = $parts[0];

if (count($parts) > 2)
{
throw new CashAddressException('Multiple \':\' characters in address!');
}
else if (count($parts) > 1)
{
$prefix = $parts[0];
$addressNoPrefix = $parts[1];
}
else
{
$prefix = self::getPrefix($address);
}

return array($prefix, $addressNoPrefix);
}

/**
* Convert a Bitcoin Cash address to an eCash address
* @param string $address The Bitcoin Cash address to convert
* @return string $eCash The eCash address
*/
public static function bch2xec($address)
{
list($inputPrefix, $addressNoPrefix) = self::splitCashAddress($address);

$prefix = "";
$unexpanded_prefix = [];
if ($inputPrefix === "bitcoincash")
{
$prefix = "ecash";
$unexpanded_prefix = self::ECASH_EXPAND_PREFIX_UNPROCESSED;
}
else if ($inputPrefix === "bchtest")
{
$prefix = "ectest";
$unexpanded_prefix = self::ECASH_EXPAND_PREFIX_TESTNET_UNPROCESSED;
}
else
{
throw new CashAddressException('Wrong prefix for bitcoincash address: ' . $inputPrefix . '!');
}

return self::buildCashAddress($prefix, $unexpanded_prefix, $addressNoPrefix);
}

/**
* Convert an eCash address to a Bitcoin Cash address
* @param string $address The eCash address to convert
* @return string $bch The Bitcoin Cash address
*/
public static function xec2bch($address)
{
list($inputPrefix, $addressNoPrefix) = self::splitCashAddress($address);

$prefix = "";
$unexpanded_prefix = [];
if ($inputPrefix === "ecash")
{
$prefix = "bitcoincash";
$unexpanded_prefix = self::BCH_EXPAND_PREFIX_UNPROCESSED;
}
else if ($inputPrefix === "ectest")
{
$prefix = "bchtest";
$unexpanded_prefix = self::BCH_EXPAND_PREFIX_TESTNET_UNPROCESSED;
}
else
{
throw new CashAddressException('Wrong prefix for eCash address: ' . $inputPrefix . '!');
}

return self::buildCashAddress($prefix, $unexpanded_prefix, $addressNoPrefix);
}
}

?>
Loading