aead_chacha20poly1305_ietf_decrypt example

$ad = '',
        $nonce = '',
        $key = ''
    ) {
        $subkey = ParagonIE_Sodium_Core_HChaCha20::hChaCha20(
            ParagonIE_Sodium_Core_Util::substr($nonce, 0, 16),
            $key
        );
        $nonceLast = "\x00\x00\x00\x00" .
            ParagonIE_Sodium_Core_Util::substr($nonce, 16, 8);

        return self::aead_chacha20poly1305_ietf_decrypt($message, $ad, $nonceLast, $subkey);
    }

    /** * AEAD Encryption with ChaCha20-Poly1305, IETF mode (96-bit nonce) * * @internal Do not use this directly. Use ParagonIE_Sodium_Compat. * * @param string $message * @param string $ad * @param string $nonce * @param string $key * @return string * @throws SodiumException * @throws TypeError */

        if (self::use_fallback('crypto_aead_chacha20poly1305_ietf_decrypt')) {
            return call_user_func(
                '\\Sodium\\crypto_aead_chacha20poly1305_ietf_decrypt',
                $ciphertext,
                $assocData,
                $nonce,
                $key
            );
        }
        if (PHP_INT_SIZE === 4) {
            return ParagonIE_Sodium_Crypto32::aead_chacha20poly1305_ietf_decrypt(
                $ciphertext,
                $assocData,
                $nonce,
                $key
            );
        }
        return ParagonIE_Sodium_Crypto::aead_chacha20poly1305_ietf_decrypt(
            $ciphertext,
            $assocData,
            $nonce,
            $key
        );

$ad = '',
        $nonce = '',
        $key = ''
    ) {
        $subkey = ParagonIE_Sodium_Core32_HChaCha20::hChaCha20(
            ParagonIE_Sodium_Core32_Util::substr($nonce, 0, 16),
            $key
        );
        $nonceLast = "\x00\x00\x00\x00" .
            ParagonIE_Sodium_Core32_Util::substr($nonce, 16, 8);

        return self::aead_chacha20poly1305_ietf_decrypt($message, $ad, $nonceLast, $subkey);
    }

    /** * AEAD Encryption with ChaCha20-Poly1305, IETF mode (96-bit nonce) * * @internal Do not use this directly. Use ParagonIE_Sodium_Compat. * * @param string $message * @param string $ad * @param string $nonce * @param string $key * @return string * @throws SodiumException * @throws TypeError */