decode_asn1.py 文件源码

def _decode_extended_key_usage(backend, sk):
    sk = backend._ffi.cast("Cryptography_STACK_OF_ASN1_OBJECT *", sk)
    sk = backend._ffi.gc(sk, backend._lib.sk_ASN1_OBJECT_free)
    num = backend._lib.sk_ASN1_OBJECT_num(sk)
    ekus = []

    for i in range(num):
        obj = backend._lib.sk_ASN1_OBJECT_value(sk, i)
        backend.openssl_assert(obj != backend._ffi.NULL)
        oid = x509.ObjectIdentifier(_obj2txt(backend, obj))
        ekus.append(oid)

    return x509.ExtendedKeyUsage(ekus)