I have to migrate from Keyczar to Tink, if the old data can be decrypted directly by Tink, we can just migrate to Tink. But Keyczar used AES-CBC mode for the encryption, I tried to find if Tink supports this but couldn't.
I could not find any option to decrypt AES-CBC, there are a lot of resources available to do the same in the case of AES-GCM though.