SOLIDPOD: Encryption is unauthenticated (AES-CTR with no MAC)

[anushkavidanage]

In the current solidpod implementation, data is encrypted using AESMode.sic is CTR mode. CTR is malleable: flipping a bit in ciphertext flips the same bit in the decrypted plaintext, and decryption succeeds silently. Furthermore, there is no MAC, no GCM tag, no AEAD anywhere in solidpod.

[gjwgit]

A major breaking change. All existing encrypted files on a POD will need to be migrated.

May be able to be done under the bonnet, but need to confirm the sharing case.

Need to be careful re current apps in use now.