For an academic application, I use AES-GCM
to encrypt my frames between 2 parties.
To enhance security, and reduce the possibility of replay, I'd like to use a TimeStamp
in my frame exchanges. But, as I use the GCM mode, I need to tranmsit the Initialisation Vector
besides the ciphertext
(and the MAC).
My idea is : could it be possible to use the IV as TimeStamp as well ?
The IV
would thus be used for decryption of the ciphetext
, and then to check if the message is not too old.
Thus, a modification in the TimeStamp
will make the ciphertext
un-decryptable.
The next step wil be to produce a TimeStamp
in a long form, as not to reduce security. Any ideas how to emit a TimeStamp
like this ?