MACBOOK ENCRYPTION HOW TO

HMAC is widely supported in most languages so finding an implementation shouldn't be an issue. This means you'll need two keys, one for 3DES and one for HMAC.

I'd recommend you use HMAC to compute a MAC for the encrypted message (HMAC(C)). I'd also recommend using something other than CBC-MAC because CBC-MAC does not provide good security. If you are using 3DES to encrypt I would recommend first encrypting your message (let's call it C).

Once there is an encryption done through CBC-MAC, how can we de-crypt >them? Triple-DES would not work for my case. If they match then the recipient knows the message was not tampered with. What the recipient does is first compute the MAC of the encrypted message, and then checks if it matches the MAC that was sent with the encrypted message. A MAC is generally send along with an encrypted message. The reason MACs exist is that even if I cannot read an encrypted messages, I can still possibly modify the encrypted message without the recipient knowing it was modified (this has caused all sorts of nasty problems in the real world).

MAC provides integrity, which means that message has not been tampered with somewhere between the sender and recipient.

Encryption provides confidentiality, which means (in the symmetric crypto case) that only someone with the correct key can read the contents of a message.

I'll try to give a brief rundown of each. MAC and encryption are two very separate things. If you're using 3DES it would be 64 bits.ДЇrom MAC to Encryption, how exactly does it work? What is MAC doing? So your MAC should be the size of the block cipher which is probably not 4 bits. What CBC-MAC does is simply take the last block of ciphertext that is output and calls that the MAC. Here's a visual of how CBC mode works via Wikipedia.

MACBOOK ENCRYPTION HOW TO

Can any one tell me how to de-crypt CBC-MAC.CBC-MAC at the end would give a 4 bit MAC. I just figured out Triple DES encryption and decryption for credit card.

Macbook encryption