// Everyone except player 1 creates a new keypair and sends it around to everyone else.
DecryptionKey broadcastNewKey(Map<VerificationKey, Address> changeAddresses)
throws TimeoutException, InterruptedException, IOException, FormatException {
DecryptionKey dk = null;
dk = crypto.makeDecryptionKey();
// Broadcast the public key and store it in the set with everyone else's.
encryptionKeys.put(vk, dk.EncryptionKey());
changeAddresses.put(vk, change);
Message message = messages.make().attach(dk.EncryptionKey());
if (change != null) {
message = message.attach(change);
}
mailbox.broadcast(message, phase.get());
return dk;
}
// In the shuffle phase, we have to receive a set of strings from the previous player and
// decrypt them all.
final Message decryptAll(Message message, DecryptionKey key, int expected)
throws IOException, InterruptedException, FormatException {
Message decrypted = messages.make();
int count = 0;
Set<String> addrs = new HashSet<>(); // Used to check that all addresses are different.
while (!message.isEmpty()) {
String encrypted = message.readString();
message = message.rest();
addrs.add(encrypted);
count++;
decrypted = decrypted.attach(key.decrypt(encrypted));
}
if (addrs.size() != count || count != expected) {
phase.set(Phase.Blame);
mailbox.broadcast(
messages.make().attach(Blame.ShuffleFailure(players.get(N))), phase.get());
return null;
}
return decrypted;
}