public static function decode()

in classes/jwt.php [47:79]

• 29 lines of code
• 11 McCabe index (conditional complexity)

    public static function decode($encoded) {
        if (empty($encoded) || !is_string($encoded)) {
            throw new \moodle_exception('errorjwtempty', 'auth_oidc');
        }
        $jwtparts = explode('.', $encoded);
        if (count($jwtparts) !== 3) {
            throw new \moodle_exception('errorjwtmalformed', 'auth_oidc');
        }

        $header = base64_decode($jwtparts[0]);
        if (!empty($header)) {
            $header = @json_decode($header, true);
        }
        if (empty($header) || !is_array($header)) {
            throw new \moodle_exception('errorjwtcouldnotreadheader', 'auth_oidc');
        }
        if (!isset($header['alg'])) {
            throw new \moodle_exception('errorjwtinvalidheader', 'auth_oidc');
        }

        $jwsalgs = ['HS256', 'HS384', 'HS512', 'RS256', 'RS384', 'RS512', 'ES256', 'ES384', 'ES512', 'PS256', 'none'];
        if (in_array($header['alg'], $jwsalgs, true) === true) {
            $body = static::decode_jws($jwtparts);
        } else {
            throw new \moodle_exception('errorjwtunsupportedalg', 'auth_oidc');
        }

        if (empty($body) || !is_array($body)) {
            throw new \moodle_exception('errorjwtbadpayload', 'auth_oidc');
        }

        return [$header, $body];
    }