void receive_service_auth_message(Channel channel, ref EncKeys keys, KeyPair picoEphemeralKey, Nonce picoNonce, ref IntPtr serviceEphemKey, ref Nonce serviceNonce)
{
Json json = new Json();
PicoBuffer buf = new PicoBuffer(0);
PicoBuffer iv = new PicoBuffer(0);
PicoBuffer cleartext = new PicoBuffer(0);
channel.read(buf);
json.deserialize(buf);
Assert.AreEqual(json.get_decimal("sessionId"), 0);
serviceEphemKey = CryptoSupport.read_base64_string_public_key(json.get_string("serviceEphemPublicKey"));
buf.clear();
Base64.decode(json.get_string("serviceNonce"), buf);
serviceNonce = new Nonce();
serviceNonce.set_buffer(buf);
Base64.decode(json.get_string("iv"), iv);
// Generate shared secrets
PicoBuffer sharedSecret;
IntPtr vEphemPriv;
SigmaKeyDeriv sigmakeyderiv;
sharedSecret = new PicoBuffer(0);
vEphemPriv = picoEphemeralKey.getprivatekey();
KeyAgreement.generate_secret(vEphemPriv, serviceEphemKey, sharedSecret);
sigmakeyderiv = new SigmaKeyDeriv();
sigmakeyderiv.set(sharedSecret, picoNonce, serviceNonce);
sharedSecret.delete();
keys.pMacKey = new PicoBuffer(0);
keys.pEncKey = new PicoBuffer(0);
keys.vMacKey = new PicoBuffer(0);
keys.vEncKey = new PicoBuffer(0);
keys.sharedKey = new PicoBuffer(0);
sigmakeyderiv.get_next_key(keys.pMacKey, 256);
sigmakeyderiv.get_next_key(keys.pEncKey, 128);
sigmakeyderiv.get_next_key(keys.vMacKey, 256);
sigmakeyderiv.get_next_key(keys.vEncKey, 128);
sigmakeyderiv.get_next_key(keys.sharedKey, 128);
sigmakeyderiv.delete();
buf.clear();
Base64.decode(json.get_string("encryptedData"), buf);
CryptoSupport.decrypt(keys.vEncKey, iv, buf, cleartext);
int start = 0;
int next = 0;
PicoBuffer servicePublicKeyBytes = new PicoBuffer(0);
PicoBuffer serviceSignature = new PicoBuffer(0);
PicoBuffer serviceMac = new PicoBuffer(0);
next = cleartext.copy_lengthprepend(start, servicePublicKeyBytes);
IntPtr servicePublicKey = CryptoSupport.read_buffer_public_key(servicePublicKeyBytes);
Assert.IsTrue(next > start);
next = cleartext.copy_lengthprepend(start, serviceSignature);
Assert.IsTrue(next > start);
next = cleartext.copy_lengthprepend(start, serviceMac);
Assert.IsTrue(next > start);
// TODO assert signature
json.delete();
buf.delete();
cleartext.delete();
servicePublicKeyBytes.delete();
serviceSignature.delete();
serviceMac.delete();
}
