/**
* Construct a group session for sending messages.
*
* @param senderKeyName The (groupId, senderId, deviceId) tuple. In this case, 'senderId' should be the caller.
* @return A SenderKeyDistributionMessage that is individually distributed to each member of the group.
*/
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);
}
}
}
/**
* Construct a group session for receiving messages from senderKeyName.
*
* @param senderKeyName The (groupId, senderId, deviceId) tuple associated with the SenderKeyDistributionMessage.
* @param senderKeyDistributionMessage A received SenderKeyDistributionMessage.
*/
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
(_groupId.Equals(that._groupId) &&
_sender.Equals(that._sender));
}
public GroupCipher(ISenderKeyStore senderKeyStore, SenderKeyName senderKeyId)
{
_senderKeyStore = senderKeyStore;
_senderKeyId = senderKeyId;
}
