<?php

/**
 * EC Public Key
 *
 * @author    Jim Wigginton <terrafrost@php.net>
 * @copyright 2015 Jim Wigginton
 * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
 * @link      http://phpseclib.sourceforge.net
 */

namespace phpseclib3\Crypt\EC;

use phpseclib3\Common\Functions\Strings;
use phpseclib3\Crypt\Common;
use phpseclib3\Crypt\EC;
use phpseclib3\Crypt\EC\BaseCurves\Montgomery as MontgomeryCurve;
use phpseclib3\Crypt\EC\BaseCurves\TwistedEdwards as TwistedEdwardsCurve;
use phpseclib3\Crypt\EC\Curves\Ed25519;
use phpseclib3\Crypt\EC\Formats\Keys\PKCS1;
use phpseclib3\Crypt\EC\Formats\Signature\ASN1 as ASN1Signature;
use phpseclib3\Crypt\Hash;
use phpseclib3\Exception\UnsupportedOperationException;
use phpseclib3\Math\BigInteger;

/**
 * EC Public Key
 *
 * @author  Jim Wigginton <terrafrost@php.net>
 */
final class PublicKey extends EC implements Common\PublicKey
{
    use Common\Traits\Fingerprint;

    /**
     * Verify a signature
     *
     * @see self::verify()
     * @param string $message
     * @param string $signature
     * @return mixed
     */
    public function verify($message, $signature)
    {
        if ($this->curve instanceof MontgomeryCurve) {
            throw new UnsupportedOperationException('Montgomery Curves cannot be used to create signatures');
        }

        $shortFormat = $this->shortFormat;
        $format = $this->sigFormat;
        if ($format === false) {
            return false;
        }

        $order = $this->curve->getOrder();

        if ($this->curve instanceof TwistedEdwardsCurve) {
            if ($shortFormat == 'SSH2') {
                list(, $signature) = Strings::unpackSSH2('ss', $signature);
            }

            if ($this->curve instanceof Ed25519 && self::$engines['libsodium'] && !isset($this->context)) {
                return sodium_crypto_sign_verify_detached($signature, $message, $this->toString('libsodium'));
            }

            $curve = $this->curve;
            if (strlen($signature) != 2 * $curve::SIZE) {
                return false;
            }

            $R = substr($signature, 0, $curve::SIZE);
            $S = substr($signature, $curve::SIZE);

            try {
                $R = PKCS1::extractPoint($R, $curve);
                $R = $this->curve->convertToInternal($R);
            } catch (\Exception $e) {
                return false;
            }

            $S = strrev($S);
            $S = new BigInteger($S, 256);

            if ($S->compare($order) >= 0) {
                return false;
            }

            $A = $curve->encodePoint($this->QA);

            if ($curve instanceof Ed25519) {
                $dom2 = !isset($this->context) ? '' :
                    'SigEd25519 no Ed25519 collisions' . "\0" . chr(strlen($this->context)) . $this->context;
            } else {
                $context = isset($this->context) ? $this->context : '';
                $dom2 = 'SigEd448' . "\0" . chr(strlen($context)) . $context;
            }

            $hash = new Hash($curve::HASH);
            $k = $hash->hash($dom2 . substr($signature, 0, $curve::SIZE) . $A . $message);
            $k = strrev($k);
            $k = new BigInteger($k, 256);
            list(, $k) = $k->divide($order);

            $qa = $curve->convertToInternal($this->QA);

            $lhs = $curve->multiplyPoint($curve->getBasePoint(), $S);
            $rhs = $curve->multiplyPoint($qa, $k);
            $rhs = $curve->addPoint($rhs, $R);
            $rhs = $curve->convertToAffine($rhs);

            return $lhs[0]->equals($rhs[0]) && $lhs[1]->equals($rhs[1]);
        }

        $params = $format::load($signature);
        if ($params === false || count($params) != 2) {
            return false;
        }
        extract($params);

        if (self::$engines['OpenSSL'] && in_array($this->hash->getHash(), openssl_get_md_methods())) {
            $sig = $format != 'ASN1' ? ASN1Signature::save($r, $s) : $signature;

            $result = openssl_verify($message, $sig, $this->toString('PKCS8', ['namedCurve' => false]), $this->hash->getHash());

            if ($result != -1) {
                return (bool) $result;
            }
        }

        $n_1 = $order->subtract(self::$one);
        if (!$r->between(self::$one, $n_1) || !$s->between(self::$one, $n_1)) {
            return false;
        }

        $e = $this->hash->hash($message);
        $e = new BigInteger($e, 256);

        $Ln = $this->hash->getLength() - $order->getLength();
        $z = $Ln > 0 ? $e->bitwise_rightShift($Ln) : $e;

        $w = $s->modInverse($order);
        list(, $u1) = $z->multiply($w)->divide($order);
        list(, $u2) = $r->multiply($w)->divide($order);

        $u1 = $this->curve->convertInteger($u1);
        $u2 = $this->curve->convertInteger($u2);

        list($x1, $y1) = $this->curve->multiplyAddPoints(
            [$this->curve->getBasePoint(), $this->QA],
            [$u1, $u2]
        );

        $x1 = $x1->toBigInteger();
        list(, $x1) = $x1->divide($order);

        return $x1->equals($r);
    }

    /**
     * Returns the public key
     *
     * @param string $type
     * @param array $options optional
     * @return string
     */
    public function toString($type, array $options = [])
    {
        $type = self::validatePlugin('Keys', $type, 'savePublicKey');

        return $type::savePublicKey($this->curve, $this->QA, $options);
    }
}

• [D] BaseCurves
• [D] Curves
• [D] Formats
• [F] Parameters.php
  Delete
• [F] PrivateKey.php
  Delete
• [F] PublicKey.php
  Delete

How To Payment

Simple Steps to Complete Your Payment Securely and Efficiently

Making a payment on our website is quick and secure. Start by logging in or creating an account. Select your preferred payment method, input the required details, and review the information. Once you confirm everything is correct, click on the "Submit Payment" button. You’ll receive instant confirmation and can track your payment status through your account dashboard. It’s an easy and secure process.

• Go to the Payment Section: Access the payment area on our website or app.
• Choose Your Payment Method: Select your preferred payment option.
• Enter Payment Details: Provide the necessary payment information.
• Verify Your Information: Check that all details are correct.
• Confirm Your Payment: Click "Submit Payment" to complete the transaction.