private static function signatureToDER()

in src/JWT.php [487:510]

• 17 lines of code
• 3 McCabe index (conditional complexity)

    private static function signatureToDER($sig)
    {
        // Separate the signature into r-value and s-value
        list($r, $s) = \str_split($sig, (int) (\strlen($sig) / 2));

        // Trim leading zeros
        $r = \ltrim($r, "\x00");
        $s = \ltrim($s, "\x00");

        // Convert r-value and s-value from unsigned big-endian integers to
        // signed two's complement
        if (\ord($r[0]) > 0x7f) {
            $r = "\x00" . $r;
        }
        if (\ord($s[0]) > 0x7f) {
            $s = "\x00" . $s;
        }

        return self::encodeDER(
            self::$asn1Sequence,
            self::encodeDER(self::$asn1Integer, $r) .
            self::encodeDER(self::$asn1Integer, $s)
        );
    }