public ulong GetNextMessageId()
{
// Documentation says that message id should be unixtime * 2^32.
// But the real world calculations in other client software looking very weird.
// Have no idea how it is actually calculated.
ulong messageId = UnixTimeUtils.GetCurrentUnixTimestampMilliseconds();
messageId = (messageId * 4294967 + (messageId * 296 / 1000)) & X4Mask;
if (messageId <= _lastMessageId)
{
messageId = _lastMessageId + 4;
}
_lastMessageId = messageId;
return(messageId);
}
protected override async Task HandleInternalAsync(IMessage responseMessage)
{
#region Notice of Ignored Error Message
/* In certain cases, a server may notify a client that its incoming message was ignored for whatever reason.
* Note that such a notification cannot be generated unless a message is correctly decoded by the server.
*
* bad_msg_notification#a7eff811 bad_msg_id:long bad_msg_seqno:int error_code:int = BadMsgNotification;
* bad_server_salt#edab447b bad_msg_id:long bad_msg_seqno:int error_code:int new_server_salt:long = BadMsgNotification;
*
* Here, error_code can also take on the following values:
*
* 16: msg_id too low (most likely, client time is wrong; it would be worthwhile to synchronize it using msg_id notifications
* and re-send the original message with the “correct” msg_id or wrap it in a container with a new msg_id if the original
* message had waited too long on the client to be transmitted)
* 17: msg_id too high (similar to the previous case, the client time has to be synchronized, and the message re-sent with the correct msg_id)
* 18: incorrect two lower order msg_id bits (the server expects client message msg_id to be divisible by 4)
* 19: container msg_id is the same as msg_id of a previously received message (this must never happen)
* 20: message too old, and it cannot be verified whether the server has received a message with this msg_id or not
* 32: msg_seqno too low (the server has already received a message with a lower msg_id but with either a higher or an equal and odd seqno)
* 33: msg_seqno too high (similarly, there is a message with a higher msg_id but with either a lower or an equal and odd seqno)
* 34: an even msg_seqno expected (irrelevant message), but odd received
* 35: odd msg_seqno expected (relevant message), but even received
* 48: incorrect server salt (in this case, the bad_server_salt response is received with the correct salt, and the message is to be re-sent with it)
* 64: invalid container.
* The intention is that error_code values are grouped (error_code >> 4): for example, the codes 0x40 - 0x4f correspond to errors in container decomposition.
*
* Notifications of an ignored message do not require acknowledgment (i.e., are irrelevant).
*
* Important: if server_salt has changed on the server or if client time is incorrect, any query will result in a notification in the above format.
* The client must check that it has, in fact, recently sent a message with the specified msg_id, and if that is the case,
* update its time correction value (the difference between the client’s and the server’s clocks) and the server salt based on msg_id
* and the server_salt notification, so as to use these to (re)send future messages.
* In the meantime, the original message (the one that caused the error message to be returned) must also be re-sent with a better msg_id and/or server_salt.
*
* In addition, the client can update the server_salt value used to send messages to the server,
* based on the values of RPC responses or containers carrying an RPC response,
* provided that this RPC response is actually a match for the query sent recently.
* (If there is doubt, it is best not to update since there is risk of a replay attack).
*
* https://core.telegram.org/mtproto/service_messages_about_messages#notice-of-ignored-error-message
*/
#endregion
var response = (IBadMsgNotification)responseMessage.Body;
var errorCode = (ErrorCode)response.ErrorCode;
Console.WriteLine(string.Format("Bad message notification received with error code: {0} ({1}).", response.ErrorCode, errorCode));
Console.WriteLine("Searching for bad message in the request manager...");
IRequest request = _requestsManager.Get(response.BadMsgId);
if (request == null)
{
Console.WriteLine(string.Format("Bad message (MsgId: 0x{0:X}) was NOT found. Ignored.", response.BadMsgId));
return;
}
if (request.Message.Seqno != response.BadMsgSeqno)
{
Console.WriteLine(
string.Format(
"Bad message (MsgId: 0x{0:X}) was found, but message sequence number is not the same ({1}) as server expected ({2}). Ignored.",
response.BadMsgId,
request.Message.Seqno,
response.BadMsgSeqno));
return;
}
var badServerSalt = response as BadServerSalt;
if (badServerSalt != null)
{
if (errorCode != ErrorCode.IncorrectServerSalt)
{
Console.WriteLine(string.Format("Error code must be '{0}' for a BadServerSalt notification, but found '{1}'.", ErrorCode.IncorrectServerSalt, errorCode));
}
Console.WriteLine(
string.Format(
"Bad server salt was in outgoing message (MsgId = 0x{0:X}, Seqno = {1}). Error code = {2}.",
badServerSalt.BadMsgId,
badServerSalt.BadMsgSeqno,
errorCode));
Console.WriteLine("Setting new salt.");
_connection.UpdateSalt(badServerSalt.NewServerSalt);
Console.WriteLine("Resending bad message with the new salt.");
await request.SendAsync();
return;
}
var badMsgNotification = response as BadMsgNotification;
if (badMsgNotification != null)
{
// TODO: implement.
switch (errorCode)
{
case ErrorCode.MsgIdIsTooSmall:
case ErrorCode.MsgIdIsTooBig:
case ErrorCode.MsgIdDuplicate:
case ErrorCode.MsgTooOld:
case ErrorCode.MsgIdBadTwoLowBytes:
ulong time = (ulong)(responseMessage.MsgId / 4294967296.0 * 1000);
ulong currentTime = UnixTimeUtils.GetCurrentUnixTimestampMilliseconds();
var timeDelta = ((long)time - (long)currentTime);
_connection.MessageIdGenerator.TimeDifference = timeDelta;
Disa.Framework.Utils.DebugPrint("Time drift set to: " + _connection.MessageIdGenerator.TimeDifference);
var newMessageId = _connection.MessageIdGenerator.GetNextMessageId();
var oldMessageId = request.Message.MsgId;
var message = new Message(newMessageId, request.Message.Seqno, request.Message.Body);
request.UpdateMessage(message);
_requestsManager.Change(newMessageId, oldMessageId);
await request.SendAsync();
break;
case ErrorCode.MsgSeqnoIsTooLow:
case ErrorCode.MsgSeqnoIsTooBig:
case ErrorCode.MsgSeqnoNotEven:
case ErrorCode.MsgSeqnoNotOdd:
case ErrorCode.IncorrectServerSalt:
case ErrorCode.InvalidContainer:
throw new NotImplementedException();
default:
throw new ArgumentOutOfRangeException();
}
}
}
