<?php

namespace Defuse\Crypto;

use Defuse\Crypto\Exception as Ex;

final class KeyOrPassword
{
    const PBKDF2_ITERATIONS    = 100000;
    const SECRET_TYPE_KEY      = 1;
    const SECRET_TYPE_PASSWORD = 2;

    /**
     * @var int
     */
    private $secret_type = 0;

    /**
     * @var Key|string
     */
    private $secret;

    /**
     * Initializes an instance of KeyOrPassword from a key.
     *
     * @param Key $key
     *
     * @return KeyOrPassword
     */
    public static function createFromKey(Key $key)
    {
        return new KeyOrPassword(self::SECRET_TYPE_KEY, $key);
    }

    /**
     * Initializes an instance of KeyOrPassword from a password.
     *
     * @param string $password
     *
     * @return KeyOrPassword
     */
    public static function createFromPassword(
        #[\SensitiveParameter]
        $password
    )
    {
        return new KeyOrPassword(self::SECRET_TYPE_PASSWORD, $password);
    }

    /**
     * Derives authentication and encryption keys from the secret, using a slow
     * key derivation function if the secret is a password.
     *
     * @param string $salt
     *
     * @throws Ex\CryptoException
     * @throws Ex\EnvironmentIsBrokenException
     *
     * @return DerivedKeys
     */
    public function deriveKeys($salt)
    {
        Core::ensureTrue(
            Core::ourStrlen($salt) === Core::SALT_BYTE_SIZE,
            'Bad salt.'
        );

        if ($this->secret_type === self::SECRET_TYPE_KEY) {
            Core::ensureTrue($this->secret instanceof Key);
            /**
             * @psalm-suppress PossiblyInvalidMethodCall
             */
            $akey = Core::HKDF(
                Core::HASH_FUNCTION_NAME,
                $this->secret->getRawBytes(),
                Core::KEY_BYTE_SIZE,
                Core::AUTHENTICATION_INFO_STRING,
                $salt
            );
            /**
             * @psalm-suppress PossiblyInvalidMethodCall
             */
            $ekey = Core::HKDF(
                Core::HASH_FUNCTION_NAME,
                $this->secret->getRawBytes(),
                Core::KEY_BYTE_SIZE,
                Core::ENCRYPTION_INFO_STRING,
                $salt
            );
            return new DerivedKeys($akey, $ekey);
        } elseif ($this->secret_type === self::SECRET_TYPE_PASSWORD) {
            Core::ensureTrue(\is_string($this->secret));
            /* Our PBKDF2 polyfill is vulnerable to a DoS attack documented in
             * GitHub issue #230. The fix is to pre-hash the password to ensure
             * it is short. We do the prehashing here instead of in pbkdf2() so
             * that pbkdf2() still computes the function as defined by the
             * standard. */

            /**
             * @psalm-suppress PossiblyInvalidArgument
             */
            $prehash = \hash(Core::HASH_FUNCTION_NAME, $this->secret, true);

            $prekey = Core::pbkdf2(
                Core::HASH_FUNCTION_NAME,
                $prehash,
                $salt,
                self::PBKDF2_ITERATIONS,
                Core::KEY_BYTE_SIZE,
                true
            );
            $akey = Core::HKDF(
                Core::HASH_FUNCTION_NAME,
                $prekey,
                Core::KEY_BYTE_SIZE,
                Core::AUTHENTICATION_INFO_STRING,
                $salt
            );
            /* Note the cryptographic re-use of $salt here. */
            $ekey = Core::HKDF(
                Core::HASH_FUNCTION_NAME,
                $prekey,
                Core::KEY_BYTE_SIZE,
                Core::ENCRYPTION_INFO_STRING,
                $salt
            );
            return new DerivedKeys($akey, $ekey);
        } else {
            throw new Ex\EnvironmentIsBrokenException('Bad secret type.');
        }
    }

    /**
     * Constructor for KeyOrPassword.
     *
     * @param int   $secret_type
     * @param mixed $secret      (either a Key or a password string)
     */
    private function __construct(
        $secret_type,
        #[\SensitiveParameter]
        $secret
    )
    {
        // The constructor is private, so these should never throw.
        if ($secret_type === self::SECRET_TYPE_KEY) {
            Core::ensureTrue($secret instanceof Key);
        } elseif ($secret_type === self::SECRET_TYPE_PASSWORD) {
            Core::ensureTrue(\is_string($secret));
        } else {
            throw new Ex\EnvironmentIsBrokenException('Bad secret type.');
        }
        $this->secret_type = $secret_type;
        $this->secret = $secret;
    }
}

• [D] Exception
• [F] Core.php
  Delete
• [F] Crypto.php
  Delete
• [F] DerivedKeys.php
  Delete
• [F] Encoding.php
  Delete
• [F] File.php
  Delete
• [F] Key.php
  Delete
• [F] KeyOrPassword.php
  Delete
• [F] KeyProtectedByPassword.php
  Delete
• [F] RuntimeTests.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.