/** * Generates an uncompressed and compressed EC public key. * * @param \Bitpay\PrivateKey $privateKey * * @return Bitpay\PublicKey */ public function generate(PrivateKey $privateKey = null) { if ($privateKey instanceof PrivateKey) { $this->setPrivateKey($privateKey); } if (!empty($this->hex)) { return $this; } if (is_null($this->privateKey)) { throw new \Exception('Please `setPrivateKey` before you generate a public key'); } if (!$this->privateKey->isGenerated()) { $this->privateKey->generate(); } if (!$this->privateKey->isValid()) { throw new \Exception('Private Key is invalid and cannot be used to generate a public key'); } $point = new Point('0x' . substr(Secp256k1::G, 2, 64), '0x' . substr(Secp256k1::G, 66, 64)); $R = Util::doubleAndAdd('0x' . $this->privateKey->getHex(), $point); $RxHex = Util::encodeHex($R->getX()); $RyHex = Util::encodeHex($R->getY()); $RxHex = str_pad($RxHex, 64, '0', STR_PAD_LEFT); $RyHex = str_pad($RyHex, 64, '0', STR_PAD_LEFT); $this->x = $RxHex; $this->y = $RyHex; $this->hex = sprintf('%s%s', $RxHex, $RyHex); $this->dec = Util::decodeHex($this->hex); return $this; }
/** * Decodes $data from BASE-58 format * * @param string $data * * @return string */ public static function decode($data) { for ($return = '0', $i = 0; $i < strlen($data); $i++) { $current = strpos(self::BASE58_CHARS, $data[$i]); $return = Math::mul($return, '58'); $return = Math::add($return, $current); } $return = Util::encodeHex($return); for ($i = 0; $i < strlen($data) && substr($data, $i, 1) == '1'; $i++) { $return = '00' . $return; } if (strlen($return) % 2 != 0) { $return = '0' . $return; } return $return; }
/** * Creates an ECDSA signature of $data. * * @param string * @return string * @throws \Exception */ public function sign($data) { if (!ctype_xdigit($this->hex)) { throw new \Exception('The private key must be in hex format.'); } if (empty($data)) { throw new \Exception('You did not provide any data to sign.'); } $e = Util::decodeHex(hash('sha256', $data)); do { if (substr(strtolower($this->hex), 0, 2) != '0x') { $d = '0x' . $this->hex; } else { $d = $this->hex; } $k = SecureRandom::generateRandom(32); $k_hex = '0x' . strtolower(bin2hex($k)); $n_hex = '0x' . Secp256k1::N; $Gx = '0x' . substr(Secp256k1::G, 2, 64); $Gy = '0x' . substr(Secp256k1::G, 66, 64); $P = new Point($Gx, $Gy); // Calculate a new curve point from Q=k*G (x1,y1) $R = Util::doubleAndAdd($k_hex, $P); $Rx_hex = Util::encodeHex($R->getX()); $Rx_hex = str_pad($Rx_hex, 64, '0', STR_PAD_LEFT); // r = x1 mod n $r = Math::mod('0x' . $Rx_hex, $n_hex); // s = k^-1 * (e+d*r) mod n $edr = Math::add($e, Math::mul($d, $r)); $invk = Math::invertm($k_hex, $n_hex); $kedr = Math::mul($invk, $edr); $s = Math::mod($kedr, $n_hex); // The signature is the pair (r,s) $signature = array('r' => Util::encodeHex($r), 's' => Util::encodeHex($s)); $signature['r'] = str_pad($signature['r'], 64, '0', STR_PAD_LEFT); $signature['s'] = str_pad($signature['s'], 64, '0', STR_PAD_LEFT); } while (Math::cmp($r, '0') <= 0 || Math::cmp($s, '0') <= 0); $sig = array('sig_rs' => $signature, 'sig_hex' => self::serializeSig($signature['r'], $signature['s'])); return $sig['sig_hex']['seq']; }
/** * @expectedException Exception */ public function testEncodeException() { Util::encodeHex(new \StdClass()); }