ParagonIE_Sodium_Compat::crypto_stream_xchacha20( int $len, string $nonce, string $key, bool $dontFallback = false ): string

3519    public static function crypto_stream_xchacha20(3520        $len,3521        $nonce,3522        #[\SensitiveParameter]3523        $key,3524        $dontFallback = false3525    ) {3526        /* Type checks: */3527        ParagonIE_Sodium_Core_Util::declareScalarType($len, 'int', 1);3528        ParagonIE_Sodium_Core_Util::declareScalarType($nonce, 'string', 2);3529        ParagonIE_Sodium_Core_Util::declareScalarType($key, 'string', 3);3530 3531        /* Input validation: */3532        if (ParagonIE_Sodium_Core_Util::strlen($nonce) !== self::CRYPTO_STREAM_XCHACHA20_NONCEBYTES) {3533            throw new SodiumException('Argument 2 must be CRYPTO_SECRETBOX_XCHACHA20_NONCEBYTES long.');3534        }3535        if (ParagonIE_Sodium_Core_Util::strlen($key) !== self::CRYPTO_STREAM_XCHACHA20_KEYBYTES) {3536            throw new SodiumException('Argument 3 must be CRYPTO_STREAM_XCHACHA20_KEYBYTES long.');3537        }3538 3539        if (self::useNewSodiumAPI() && !$dontFallback) {3540            return sodium_crypto_stream_xchacha20($len, $nonce, $key);3541        }3542        if (PHP_INT_SIZE === 4) {3543            return ParagonIE_Sodium_Core32_XChaCha20::stream($len, $nonce, $key);3544        }3545        return ParagonIE_Sodium_Core_XChaCha20::stream($len, $nonce, $key);3546    }