def decrypt(self, senderKeyMessageBytes):
"""
:type senderKeyMessageBytes: bytearray
"""
try:
record = self.senderKeyStore.loadSenderKey(self.senderKeyName)
if record.isEmpty():
raise NoSessionException("No sender key for: %s" % self.senderKeyName)
senderKeyMessage = SenderKeyMessage(serialized=bytes(senderKeyMessageBytes))
senderKeyState = record.getSenderKeyState(senderKeyMessage.getKeyId())
senderKeyMessage.verifySignature(senderKeyState.getSigningKeyPublic())
senderKey = self.getSenderKey(senderKeyState, senderKeyMessage.getIteration())
plaintext = self.getPlainText(senderKey.getIv(), senderKey.getCipherKey(), senderKeyMessage.getCipherText())
self.senderKeyStore.storeSenderKey(self.senderKeyName, record)
return plaintext
except (InvalidKeyException, InvalidKeyIdException) as e:
raise InvalidMessageException(e)
