Method add_extension

src/cryptography/x509/base.py:498–519

Adds an X.509 extension to the certificate.

(
        self, extval: ExtensionType, critical: bool
    )

        )

    def add_extension(
        self, extval: ExtensionType, critical: bool
    ) -> CertificateBuilder:
        """
        Adds an X.509 extension to the certificate.
        """
        if not isinstance(extval, ExtensionType):
            raise TypeError("extension must be an ExtensionType")

        extension = Extension(extval.oid, critical, extval)
        _reject_duplicate_extension(extension, self._extensions)

        return CertificateBuilder(
            self._issuer_name,
            self._subject_name,
            self._public_key,
            self._serial_number,
            self._not_valid_before,
            self._not_valid_after,
            [*self._extensions, extension],
            self._public_key_rsa_padding,
        )

    def sign(
        self,