def reencrypt(
self, rekey: Tuple[tuple, Tuple[bytes,
bytes]], ciphertext: Tuple[bytes,
bytes]
) -> Tuple[Tuple[bytes, bytes], Tuple[bytes, bytes]]:
"""
Re-encrypt for public key
rekey is (rk, encrypted_eph), same as output of rekey()
ciphertext is a tuple in the same format as output of encrypt()
Output is two tuples: data encrypted with an ephemeral key
and the ephemeral private key encrypted for recepient (Bob)
"""
rk, encrypted_eph = rekey
rk = umbral.RekeyFrag(rk[0],
ec.deserialize(self.pre.ecgroup, rk[1]),
pre=PRE)
ekey, edata = ciphertext
ekey = umbral.EncryptedKey(ekey=ec.deserialize(self.pre.ecgroup,
ekey[0]),
re_id=ekey[1])
ekey = self.pre.reencrypt(rk, ekey)
ekey = (ec.serialize(ekey.ekey), ekey.re_id)
return (ekey, edata), encrypted_eph
def ecies_reencrypt(
rekey: Union[bytes, umbral.RekeyFrag],
enc_key: Union[bytes, umbral.EncryptedKey],
) -> umbral.EncryptedKey:
"""
Re-encrypts the key provided.
:param rekey: Re-encryption key to use
:param enc_key: Encrypted key to re-encrypt
:return: The re-encrypted key
"""
if type(rekey) == bytes:
rekey = umbral.RekeyFrag(None, priv_bytes2ec(rekey))
if type(enc_key) == bytes:
enc_key = umbral.EncryptedKey(priv_bytes2ec(enc_key), None)
return PRE.reencrypt(rekey, enc_key)