Module orion::hazardous::hmac

HMAC-SHA512 (Hash-based Message Authentication Code) as specified in the RFC 2104.

Parameters:

• secret_key: The authentication key
• data: Data to be authenticated

See RFC for more information.

Exceptions:

An exception will be thrown if:

• Either finalize() or finalize_with_dst() is called twice without a reset() in between
• update() is called after finalize() without a reset() in between

Security:

The secret key should always be generated using a CSPRNG. The gen_rand_key function in util can be used for this. The recommended length for a secret key is 64.

Example:

Generating HMAC:

use orion::hazardous::hmac;
use orion::utilities::util;

let mut key = [0u8; 64];
util::gen_rand_key(&mut key).unwrap();
let msg = "Some message.";

let mut mac = hmac::init(&key);
mac.update(msg.as_bytes()).unwrap();
mac.finalize().unwrap();

Verifying HMAC:

use orion::hazardous::hmac;
use orion::utilities::util;

let mut key = [0u8; 64];
util::gen_rand_key(&mut key).unwrap();
let msg = "Some message.";

let mut mac = hmac::init(&key);
mac.update(msg.as_bytes()).unwrap();

assert!(hmac::verify(&mac.finalize().unwrap(), &key, msg.as_bytes()).unwrap());

Structs

Hmac	HMAC-SHA512 (Hash-based Message Authentication Code) as specified in the RFC 2104.

Functions

init	Initialize Hmac struct with a given key.
verify	Verify a HMAC-SHA512 MAC in constant time.