Module irmaseal_core::kem::mr

This module contains a generic implementation shell around all three KEMs to use in a multi-recipient setting. This feature requires the alloc crate.

Example usage:

In this example we encapsulate a session key for two recipients.

use ibe::kem::IBKEM;
use ibe::kem::mr::{MultiRecipient, MultiRecipientCiphertext};
use ibe::kem::cgw_kv::CGWKV;
use ibe::Derive;

let mut rng = rand::thread_rng();

let ids = ["email:w.geraedts@sarif.nl", "email:l.botros@cs.ru.nl"];
let derived: Vec<<CGWKV as IBKEM>::Id> = ids.iter().map(|id| <CGWKV as IBKEM>::Id::derive_str(id)).collect();

// Create a master key pair.
let (pk, sk) = CGWKV::setup(&mut rng);

// Generate USKs for both identities.
let usk1 = CGWKV::extract_usk(None, &sk, &derived[0], &mut rng);
let usk2 = CGWKV::extract_usk(None, &sk, &derived[1], &mut rng);

// Encapsulate a single session key for two recipients.
let (cts, k) = CGWKV::multi_encaps(&pk, &derived[..], &mut rng);

// NOTE: Here we would send ciphertext over the network.

let k1 = CGWKV::multi_decaps(Some(&pk), &usk1, &cts[0]).unwrap();
let k2 = CGWKV::multi_decaps(Some(&pk), &usk2, &cts[1]).unwrap();

assert_eq!(k, k1);
assert_eq!(k, k2);

Structs

MultiRecipientCiphertext

A multi-recipient ciphertext.

Traits

MultiRecipient

Trait that captures multi-recipient encapsulation/decapsulation.