decode_asn1.py 文件源码

def _decode_authority_key_identifier(backend, akid):
    akid = backend._ffi.cast("AUTHORITY_KEYID *", akid)
    akid = backend._ffi.gc(akid, backend._lib.AUTHORITY_KEYID_free)
    key_identifier = None
    authority_cert_issuer = None

    if akid.keyid != backend._ffi.NULL:
        key_identifier = backend._ffi.buffer(
            akid.keyid.data, akid.keyid.length
        )[:]

    if akid.issuer != backend._ffi.NULL:
        authority_cert_issuer = _decode_general_names(
            backend, akid.issuer
        )

    authority_cert_serial_number = _asn1_integer_to_int_or_none(
        backend, akid.serial
    )

    return x509.AuthorityKeyIdentifier(
        key_identifier, authority_cert_issuer, authority_cert_serial_number
    )