public function verifies($hash, Signature $signature)
{
if (extension_loaded('gmp') && USE_EXT == 'GMP') {
$G = $this->generator;
$n = $this->generator->getOrder();
$point = $this->point;
$r = $signature->getR();
$s = $signature->getS();
if (gmp_cmp($r, 1) < 0 || gmp_cmp($r, gmp_sub($n, 1)) > 0) {
return false;
}
if (gmp_cmp($s, 1) < 0 || gmp_cmp($s, gmp_sub($n, 1)) > 0) {
return false;
}
$c = NumberTheory::inverse_mod($s, $n);
$u1 = gmp_Utils::gmp_mod2(gmp_mul($hash, $c), $n);
$u2 = gmp_Utils::gmp_mod2(gmp_mul($r, $c), $n);
$xy = Point::add(Point::mul($u1, $G), Point::mul($u2, $point));
$v = gmp_Utils::gmp_mod2($xy->getX(), $n);
if (gmp_cmp($v, $r) == 0) {
return true;
} else {
return false;
}
} else {
if (extension_loaded('bcmath') && USE_EXT == 'BCMATH') {
$G = $this->generator;
$n = $this->generator->getOrder();
$point = $this->point;
$r = $signature->getR();
$s = $signature->getS();
if (bccomp($r, 1) == -1 || bccomp($r, bcsub($n, 1)) == 1) {
return false;
}
if (bccomp($s, 1) == -1 || bccomp($s, bcsub($n, 1)) == 1) {
return false;
}
$c = NumberTheory::inverse_mod($s, $n);
$u1 = bcmod(bcmul($hash, $c), $n);
$u2 = bcmod(bcmul($r, $c), $n);
$xy = Point::add(Point::mul($u1, $G), Point::mul($u2, $point));
$v = bcmod($xy->getX(), $n);
if (bccomp($v, $r) == 0) {
return true;
} else {
return false;
}
} else {
throw new ErrorException("Please install BCMATH or GMP");
}
}
}
public function GOST_verifies($hash, Signature $signature)
{
if (extension_loaded('gmp') && USE_EXT == 'GMP') {
$G = $this->generator;
//P
$n = $this->generator->getOrder();
//q
$point = $this->point;
//Q
$r = $signature->getR();
$s = $signature->getS();
if (gmp_cmp($r, 1) < 0 || gmp_cmp($r, gmp_sub($n, 1)) > 0) {
return false;
}
if (gmp_cmp($s, 1) < 0 || gmp_cmp($s, gmp_sub($n, 1)) > 0) {
return false;
}
//step 3 GOST
$e = gmp_Utils::gmp_mod2($hash, $n);
if (gmp_cmp($e, '0') === 0) {
$e = gmp_init('1');
}
// step 4 GOST
$v = gmp_strval(gmp_invert($e, $n));
// step 5 GOST
$z1 = gmp_Utils::gmp_mod2(gmp_mul($s, $v), $n);
$z2 = gmp_Utils::gmp_mod2(gmp_mul(gmp_neg($r), $v), $n);
// step 6 GOST
$C = Point::add(Point::mul($z1, $G), Point::mul($z2, $point));
$R = gmp_Utils::gmp_mod2($C->getX(), $n);
if (0) {
echo "n - " . $n . "\n";
echo "h - " . $hash . "\n";
echo "e - " . gmp_Utils::gmp_dechex($e) . "\n";
echo "v - " . gmp_Utils::gmp_dechex($v) . "\n";
echo "r - " . $r . "\n";
echo "s - " . $s . "\n";
echo "z1 - " . gmp_Utils::gmp_dechex($z1) . "\nz2 - " . gmp_Utils::gmp_dechex($z2) . "\n";
echo "Q - " . $point . "\nG - " . $G . "\n";
echo "C - " . $C . "\nR - " . $R . "\n";
}
if (gmp_cmp($R, $r) == 0) {
return true;
} else {
return false;
}
} else {
throw new ErrorException("Please install GMP");
}
}
/**
* Encode Signature
*
* This function accepts a signature object, and information about
* the txout being spent, and the relevant key for signing, and
* encodes the signature in DER format.
*
* @param \Signature $signature
* @return string
*/
public static function encode_signature(\Signature $signature)
{
// Pad r and s to 64 characters.
$rh = str_pad(BitcoinLib::hex_encode($signature->getR()), 64, '0', STR_PAD_LEFT);
$sh = str_pad(BitcoinLib::hex_encode($signature->getS()), 64, '0', STR_PAD_LEFT);
// Check if the first byte of each has its highest bit set,
$t1 = unpack("H*", pack('H*', substr($rh, 0, 2)) & pack('H*', '80'));
$t2 = unpack("H*", pack('H*', substr($sh, 0, 2)) & pack('H*', '80'));
// if so, the result != 00, and must be padded.
$r = $t1[1] !== '00' ? '00' . $rh : $rh;
$s = $t2[1] !== '00' ? '00' . $sh : $sh;
// Create the signature.
$der_sig = '30' . self::_dec_to_bytes(4 + (strlen($r) + strlen($s)) / 2, 1) . '02' . self::_dec_to_bytes(strlen($r) / 2, 1) . $r . '02' . self::_dec_to_bytes(strlen($s) / 2, 1) . $s . '01';
return $der_sig;
}
