Tag Info

New answers tagged

0

Since you already trust the server to securely delete the plaintext message after decrypting it for a client, you can trust it to delete the encrypted versions too. So for instance the case of 3 keys K1 .. K3 and plaintext P, store K1(P), K1(K2(P)),K1(K2(K3(P))) since they all start with K1, that is the only key that can be used at first. after K1 is ...


2

As Trevis says, it's at least as safe: there's a simple reduction from the salted to the non-salted MAC, assuming the latter is secure in the standard "existential unforgeability under chosen message attacks". Assuming the adversary has full control of the salt, it also won't buy you anything security wise. In a slightly different setting, where the salt ...


2

Safe, yes, but it doesn't really give you anything. The only use for a salt is to mitigate precomputation attacks against a password. Since it is public, it gives you no extra MAC security. By the property of the MAC, no adversary can forge one without knowing the key, and by the security of your KDF (which includes the salt) no one should be able to get ...



Top 50 recent answers are included