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;
}
}
internal static bool Deserialize(Stream raw, StreamCapabilities _streamCapabilities)
{
var reader = new N2HBinaryReader(raw);
//var length = raw.GetAvaliableByteCounts();
//if (length < 28)
//{
// Logger.FATAL("Not enough data");
// return false;
//}
var ver = reader.ReadUInt64();
if (ver != Utils.__STREAM_CAPABILITIES_VERSION)
{
Logger.FATAL("Invalid stream capabilities version. Wanted: {0}; Got: {1}",
Utils.__STREAM_CAPABILITIES_VERSION, ver);
return false;
}
_streamCapabilities.Clear();
_streamCapabilities.VideoCodecId = (VideoCodec)reader.ReadByte();
_streamCapabilities.AudioCodecId = (AudioCodec)reader.ReadByte();
_streamCapabilities.BandwidthHint = reader.ReadUInt32();
if (_streamCapabilities.VideoCodecId == VideoCodec.H264 && !VideoAvc.Deserialize(raw, out _streamCapabilities.Avc))
{
Logger.FATAL("Unable to deserialize avc");
return false;
}
if (_streamCapabilities.AudioCodecId == AudioCodec.Aac &&
!AudioAac.Deserialize(raw, out _streamCapabilities.Aac))
{
Logger.FATAL("Unable to deserialize aac");
return false;
}
return true;
}
public static bool Deserialize(Stream src, out VideoAvc dest)
{
dest = new VideoAvc();
if (src.GetAvaliableByteCounts() < 2)
{
Logger.FATAL("Not enough data");
return false;
}
var reader = new N2HBinaryReader(src);
var _spsLength = reader.ReadUInt16();
if (src.GetAvaliableByteCounts() < _spsLength + 2 + 8)
{
Logger.FATAL("Not enough data");
return false;
}
var psps = reader.ReadBytes(_spsLength);
var _ppsLength = reader.ReadUInt16();
if (src.GetAvaliableByteCounts() < _ppsLength + 2 + 8)
{
Logger.FATAL("Not enough data");
return false;
}
var ppps = reader.ReadBytes(_ppsLength);
dest.Init(psps, ppps);
dest._widthOverride = reader.ReadUInt32();
dest._heightOverride = reader.ReadUInt32();
return true;
}
public static bool Deserialize(Stream src, out AudioAac dest)
{
dest = new AudioAac();
var length = src.GetAvaliableByteCounts();
if (length < 4)
{
Logger.FATAL("Not enough data");
return false;
}
using (var reader = new N2HBinaryReader(src))
{
dest._aacLength = reader.ReadUInt32();
if (length < 4 + dest._aacLength)
{
Logger.FATAL("Not enough data");
return false;
}
if (!dest.Init(src, (int) dest._aacLength))
{
Logger.FATAL("Unable to init AAC");
return false;
}
}
return true;
}
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;
}
}
