utils.py 文件源码

def generate_fingerprint(public_key):
    try:
        pub_bytes = public_key.encode('utf-8')
        # Test that the given public_key string is a proper ssh key. The
        # returned object is unused since pyca/cryptography does not have a
        # fingerprint method.
        serialization.load_ssh_public_key(
            pub_bytes, backends.default_backend())
        pub_data = base64.b64decode(public_key.split(' ')[1])
        digest = hashes.Hash(hashes.MD5(), backends.default_backend())
        digest.update(pub_data)
        md5hash = digest.finalize()
        raw_fp = binascii.hexlify(md5hash)
        if six.PY3:
            raw_fp = raw_fp.decode('ascii')
        return ':'.join(a + b for a, b in zip(raw_fp[::2], raw_fp[1::2]))
    except Exception:
        raise exception.InvalidKeypair(
            reason=_('failed to generate fingerprint'))