public void Acknowledgment(N2HBinaryReader reader)
{
var bufferSize = reader.Read7BitLongValue();
if (bufferSize == 0)
{
Fail("Negative acknowledgment");
return;
}
ulong stageAckPrec = _stageAck;
var stageReaden = reader.Read7BitLongValue();
Debug.WriteLine("ack:id:{0},stage:{1},accId:{2}",Id, stageReaden,FlowId);
var stage = _stageAck + 1;
if (stageReaden > _stage)
{
Logger.FATAL(
"Acknowledgment received {0} superior than the current sending stage {1} on flowWriter {2}",
stageReaden, _stage, Id);
_stageAck = _stage;
}
else if (stageReaden <= _stageAck)
{
if (reader.BaseStream.GetAvaliableByteCounts() == 0)
Logger.Debug("Acknowledgment {0} obsolete on flowWriter {1}", stageReaden, Id);
}
else
{
_stageAck = stageReaden;
}
var maxStageRecv = stageReaden;
var pos = reader.BaseStream.Position;
while (reader.BaseStream.GetAvaliableByteCounts() > 0)
{
maxStageRecv += reader.Read7BitLongValue() + reader.Read7BitLongValue() + 2;
}
if (pos != reader.BaseStream.Position)
{
reader.BaseStream.Position = pos;
}
ulong lostCount = 0;
ulong lostStage = 0;
bool repeated = false;
bool header = true;
bool stop = false;
var messageNode = _messagesSent.First;
while (messageNode!=null)
{
var message = messageNode.Value;
//if (stop) break;
// if (message.Fragments.Count == 0) continue;
//var fragmentsLen = message.Fragments.Count;
for (var itFrag = 0; itFrag < message.Fragments.Count;)
{
if (_stageAck >= message.Fragments[itFrag].Stage)
{
stage++;
_ackCount++;
message.Fragments.RemoveAt(itFrag);
continue;
}
while (!stop)
{
if (lostCount == 0)
{
if (reader.BaseStream.GetAvaliableByteCounts() > 0)
{
lostCount = reader.Read7BitLongValue() + 1;
lostStage = stageReaden + 1;
stageReaden = lostStage + lostCount + reader.Read7BitLongValue();
}
else
{
stop = true;
break;
}
}
if (lostStage > _stage)
{
Logger.FATAL("Lost information received {0} have not been yet sent on flowWriter {1}",
lostStage, Id);
stop = true;
}
else if (lostStage <= _stageAck)
{
--lostCount;
++lostStage;
continue;
}
break;
}
if (stop) break;
if (lostStage != stage)
{
if (repeated)
{
++stage;
++itFrag;
header = true;
}
else
{
_stageAck = stage;
}
continue;
}
if (!message.Repeatable)
{
if (repeated)
{
itFrag++;
stage++;
header = true;
}
else
{
Logger.INFO("FlowWriter {0} : message {1} lost", Id, stage);
--_ackCount;
++_lostCount;
_stageAck = stage;
}
--lostCount;
++lostStage;
continue;
}
repeated = true;
if (message.Fragments[itFrag].Stage >= maxStageRecv)
{
++stage;
header = true;
--lostCount;
++lostStage;
itFrag++;
continue;
}
Logger.Debug("FlowWriter {0} : stage {1} reapeated", Id, stage);
uint available;
var fragmentOffset = message.Fragments[itFrag].Offset;
var content = message.GetReader(fragmentOffset, out available);
message.Fragments[itFrag] = new Message.FragmentInfo(fragmentOffset, _stage);
var contentSize = available;
itFrag++;
byte flags = 0;
if (fragmentOffset > 0) flags |= MESSAGE_WITH_BEFOREPART;
if (itFrag != message.Fragments.Count)
{
flags |= MESSAGE_WITH_AFTERPART;
contentSize = message.Fragments[itFrag].Offset - fragmentOffset;
}
var size = contentSize + 4;
var bandWriter = Band.Writer;
if (!header && size > bandWriter.AvaliableBufferCounts)
{
Band.Flush();
header = true;
}
if (header) size += HeaderSize(stage);
if (size > bandWriter.AvaliableBufferCounts) Band.Flush();
size -= 3;
Flush(Band.WriteMessage((byte)(header ? 0x10 : 0x11), (ushort)size), stage, flags, header,
content, (ushort)contentSize);
available -= contentSize;
header = false;
--lostCount;
++lostStage;
++stage;
}
if (message.Fragments.Count == 0)
{
if (message.Repeatable) --_repeatable;
if (_ackCount > 0)
{
uint available;
uint size;
var reader1 = message.MemAck(out available, out size);
AckMessageHandler(_ackCount, _lostCount, reader1, available, size);
_ackCount = _lostCount = 0;
}
_messagesSent.Remove(messageNode);
Debug.WriteLine("sentremove{0} on flowWriter {1}", _stageAck, Id);
message.Recycle();
}
messageNode = messageNode.Next;
}
if (lostCount > 0 && reader.BaseStream.GetAvaliableByteCounts() > 0)
Logger.FATAL("Some lost information received have not been yet sent on flowWriter {0}", Id);
// rest messages repeatable?
if (_repeatable == 0)
_trigger.Stop();
else if (_stageAck > stageAckPrec || repeated)
_trigger.Reset();
}
private byte PerformHandshake(byte id, N2HBinaryReader reader, long oldPos)
{
//Logger.Debug("PerformHandshake{0}", id);
switch (id)
{
case 0x30:
reader.ReadByte();
var epdLen = reader.ReadByte() - 1;
var type = reader.ReadByte();
var epd = reader.ReadBytes(epdLen);
var tag = reader.ReadBytes(16);
Writer.Write((byte)tag.Length);
Writer.Write(tag);
if (type == 0x0F)
return Handler.PerformHandshake(tag, Writer,Peer.Address, epd);
if (type == 0x0a)
{
var tagstr = tag.BytesToString();
var attempt = GetHelloAttempt<HelloAttempt>(tagstr);
ushort port;
string host;
RtmfpUtils.UnpackUrl(epd.BytesToString(), out host, out port, out Peer.Path,out Peer.Properties);
var addresses = new List<string>();
Peer.OnHandshake(attempt.Count + 1, addresses);
if (addresses.Count > 0)
{
for (var i = 0; i < addresses.Count; i++)
{
if (addresses[i] == "again")
{
addresses[i] = host + ":" + port;
Writer.WriteAddress(new IPEndPoint(IPAddress.Parse(host),port),i==0 );
}
}
return 0x71;
}
CreateCookie(Writer, attempt, tag, epd.BytesToString());
Writer.Write(_certificat);
return 0x70;
}
else
{
Logger.FATAL("Unkown handshake first way with '{0}' type", type);
}
return 0;
case 0x38:
FarId = reader.ReadUInt32();
if (reader.Read7BitLongValue() != CookieComputing.COOKIE_SIZE)
{
return 0;
}
var cookieKey = reader.ReadBytes(CookieComputing.COOKIE_SIZE).BytesToString();
reader.BaseStream.Position -= CookieComputing.COOKIE_SIZE;
if (!_cookies.ContainsKey(cookieKey))
{
Logger.WARN("Cookie {0} unknown, maybe already connected (udpBuffer congested?)", cookieKey);
return 0;
}
var cookie = _cookies[cookieKey];
cookie.PeerAddress = Peer.Address;
if (cookie.FarId == 0)
{
cookie.FarId = FarId;
reader.BaseStream.Position += CookieComputing.COOKIE_SIZE;
var size = reader.Read7BitLongValue();
var buffer = reader.ReadBytes((int) size);
uint tempSize = 0;
cookie.PeerId = Target.Sha256.ComputeHash(buffer, 0, (int)size);
//Native.EVP_Digest(buffer, (uint)size, cookie.PeerId, ref tempSize, Native.EVP_sha256(), IntPtr.Zero);
reader.BaseStream.Position -= (long) size;
var initiatorKeySize = (int) (reader.Read7BitValue() - 2);
reader.BaseStream.Position += 2;
cookie.CookieComputing.InitiatorKey = new byte[initiatorKeySize];
reader.BaseStream.Read(cookie.CookieComputing.InitiatorKey, 0, initiatorKeySize);
//cookie.CookieComputing.InitiatorKey = reader.ReadBytes((int) initiatorKeySize);
cookie.CookieComputing.InitiatorNonce = reader.ReadBytes((int) reader.Read7BitValue());
Writer.BaseStream.Position = oldPos;
tempSize = reader.ReadByte();//0x58
if(tempSize!=0x58)Logger.WARN("not 0x58!!");
cookie.ComputeKeys();
}
else if(cookie.Id>0)
{
cookie.Read(Writer.BaseStream);
return 0x78;
}
return 0;
default:
Logger.FATAL("Unkown handshake packet id {0}", id);
return 0;
}
}
public override void PacketHandler(N2HBinaryReader reader)
{
if(Checked){
lock (Writer)
{
base.PacketHandler(reader);
}
return;
}
var marker = reader.ReadByte();
if (marker != 0x0b)
{
Logger.FATAL("Marker hand shake wrong:should be 0b and not {0:X}", marker);
return;
}
var time = reader.ReadUInt16();
var type = reader.ReadByte();
var length = reader.ReadUInt16();
byte[] tag;
Logger.Debug("handshake {0:X} len:{1}",type,length);
switch (type)
{
case 0x70:
tag = reader.ReadBytes(reader.ReadByte());
var cookieBytes = reader.ReadBytes(reader.ReadByte());
var targetCertificat = reader.ReadBytes((int)reader.BaseStream.GetAvaliableByteCounts());
var nonce = new byte[0];
_dh = RtmfpUtils.BeginDiffieHellman(ref nonce, true);
Peer.Id = Target.Sha256.ComputeHash(nonce, 0, nonce.Length);
HandShake38(cookieBytes, nonce);
_handshake = () => HandShake38(cookieBytes, nonce);
break;
case 0x71:
tag = reader.ReadBytes(reader.ReadByte());
var flag = reader.ReadByte();
var address = new IPEndPoint(new IPAddress(reader.ReadBytes(4)), reader.ReadInt16());
Target.Address.Port = address.Port;
Logger.Debug("redirect to {0}",address.ToString());
Handler.FarProtocol.IOHandler.Socket.Connect(Target.Address);
_handshake();
break;
case 0x78:
FarId = reader.ReadUInt32();
var targetNonce = reader.ReadBytes((int)reader.Read7BitLongValue());
var must58 = reader.ReadByte();
Debug.WriteLineIf(must58!=0x58,$"must58!{must58}");
var key = new byte[RtmfpUtils.KEY_SIZE];
Buffer.BlockCopy(targetNonce, targetNonce.Length - RtmfpUtils.KEY_SIZE, key, 0, RtmfpUtils.KEY_SIZE);
var sharedSecret = _dh.CreateSharedKey(key);
byte[] decryptKey;
byte[] encryptKey;
RtmfpUtils.ComputeAsymetricKeys(sharedSecret, _certificat, targetNonce, out encryptKey, out decryptKey);
Checked = true;
_handshakeTimeoutTimer.Stop();
AesEncrypt = new AESEngine(encryptKey, AESEngine.Direction.ENCRYPT);
AesDecrypt = new AESEngine(decryptKey);
PrevAesType = AESEngine.AESType.DEFAULT;
Application = Handler.Application;
Handler.CreateSession(Peer, null);
break;
default:
break;
}
}
