/// <summary>
/// Construct a group session for sending messages.
/// </summary>
/// <param name="senderKeyName">The (groupId, senderId, deviceId) tuple. In this case, 'senderId' should be the
/// caller.</param>
/// <returns>A SenderKeyDistributionMessage that is individually distributed to each member of the group.</returns>
public SenderKeyDistributionMessage create(SenderKeyName senderKeyName)
{
lock (GroupCipher.LOCK)
{
try
{
SenderKeyRecord senderKeyRecord = senderKeyStore.loadSenderKey(senderKeyName);
if (senderKeyRecord.isEmpty())
{
senderKeyRecord.setSenderKeyState(KeyHelper.generateSenderKeyId(),
0,
KeyHelper.generateSenderKey(),
KeyHelper.generateSenderSigningKey());
senderKeyStore.storeSenderKey(senderKeyName, senderKeyRecord);
}
SenderKeyState state = senderKeyRecord.getSenderKeyState();
return(new SenderKeyDistributionMessage(state.getKeyId(),
state.getSenderChainKey().getIteration(),
state.getSenderChainKey().getSeed(),
state.getSigningKeyPublic()));
}
catch (Exception e) when(e is InvalidKeyIdException || e is InvalidKeyException)
{
throw new Exception(e.Message);
}
}
}
/// <summary>
/// Construct a group session for receiving messages from senderKeyName.
/// </summary>
/// <param name="senderKeyName">The (groupId, senderId, deviceId) tuple associated with the SenderKeyDistributionMessage.</param>
/// <param name="senderKeyDistributionMessage">A received SenderKeyDistributionMessage.</param>
public void process(SenderKeyName senderKeyName, SenderKeyDistributionMessage senderKeyDistributionMessage)
{
lock (GroupCipher.LOCK)
{
SenderKeyRecord senderKeyRecord = senderKeyStore.loadSenderKey(senderKeyName);
senderKeyRecord.addSenderKeyState(senderKeyDistributionMessage.getId(),
senderKeyDistributionMessage.getIteration(),
senderKeyDistributionMessage.getChainKey(),
senderKeyDistributionMessage.getSignatureKey());
senderKeyStore.storeSenderKey(senderKeyName, senderKeyRecord);
}
}
public override bool Equals(Object other)
{
if (other == null)
{
return(false);
}
if (!(other is SenderKeyName))
{
return(false);
}
SenderKeyName that = (SenderKeyName)other;
return
(this.groupId.Equals(that.groupId) &&
this.sender.Equals(that.sender));
}
public GroupCipher(SenderKeyStore senderKeyStore, SenderKeyName senderKeyId)
{
this.senderKeyStore = senderKeyStore;
this.senderKeyId = senderKeyId;
}