private void SendUnfragmentedSessionConfirmed()
{
var ri = new BufLen(Session.MyRouterContext.MyRouterInfo.ToByteArray());
SendMessage(
SSUHeader.MessageTypes.SessionConfirmed,
Session.MACKey,
Session.SharedKey,
(start, writer) =>
{
writer.Write8((byte)((0 << 4) + 1));
writer.WriteFlip16((ushort)ri.Length);
writer.Write(ri);
Session.SignOnTimeA = BufUtils.Flip32(SSUHost.SSUTime(DateTime.UtcNow));
writer.Write32(Session.SignOnTimeA);
var padding = BufUtils.Get16BytePadding(Session.MyRouterContext.Certificate.SignatureLength + (writer - start));
writer.Write(BufUtils.Random(padding));
var baddr = new BufLen(Session.RemoteEP.Address.GetAddressBytes());
var bport = BufUtils.Flip16BL((ushort)Session.RemoteEP.Port);
#if LOG_ALL_TRANSPORT
Logging.LogTransport(string.Format("SSU SessionConfirmedState {0}: X for signature {1}.",
Session.DebugId, Request.X.Key));
Logging.LogTransport(string.Format("SSU SessionConfirmedState {0}: Y for signature {1}.",
Session.DebugId, Request.Y.Key));
Logging.LogTransport(string.Format("SSU SessionConfirmedState {0}: Alice address for signature {1}. Port {2}.",
Session.DebugId, Request.SCMessage.Address, Request.SCMessage.Port));
Logging.LogTransport(string.Format("SSU SessionConfirmedState {0}: Bob address for signature {1}. Port {2}.",
Session.DebugId, baddr, bport));
Logging.LogTransport(string.Format("SSU SessionConfirmedState {0}: Relay tag {1}. Signon time {2}.",
Session.DebugId, Request.SCMessage.RelayTag, (BufLen)Session.SignOnTimeA));
#endif
var sign = I2PSignature.DoSign(Session.MyRouterContext.PrivateSigningKey,
Request.X.Key, Request.Y.Key,
Request.SCMessage.Address, Request.SCMessage.Port,
baddr, bport,
Request.SCMessage.RelayTag, (BufLen)Session.SignOnTimeA
);
writer.Write(sign);
#if LOG_ALL_TRANSPORT
Logging.LogTransport(string.Format("SessionConfirmedState {0}: sending unfragmented SessionConfirmed. {1} bytes [0x{1:X}].",
Session.DebugId,
writer - start - SSUHeader.FIXED_HEADER_SIZE));
#endif
return(true);
});
}
private BufLen ReadBlock()
{
var inbufend = 2 + BlockLength + 4;
inbufend += BufUtils.Get16BytePadding(inbufend);
while (InBufPos < inbufend)
{
if (MySocket.Available > 0)
{
var len = MySocket.Receive(InBuf, InBufPos, inbufend - InBufPos, SocketFlags.None);
if (len == 0)
{
throw new EndOfStreamEncounteredException();
}
InBufPos += len;
}
else
{
Thread.Sleep(400);
if (!MySocket.Connected)
{
throw new EndOfStreamEncounteredException();
}
}
}
Cipher.ProcessBytes(new BufLen(InBuf, 16, InBufPos - 16));
var checksum = LZUtils.Adler32(1, new BufLen(InBuf, 0, InBufPos - 4));
var blocksum = BufUtils.Flip32(InBuf, InBufPos - 4);
if (checksum != blocksum)
{
throw new ChecksumFailureException("NTCPReader: Received Adler checksum mismatch.");
}
var result = new BufLen(InBuf, 2, BlockLength);
BlockLength = -1;
#if LOG_ALL_TRANSPORT
Logging.LogTransport(string.Format("NTCPReader +{1}+ block received: {0} bytes [0x{0:X}]", result.Length, Context.TransportInstance));
#endif
return(result.Clone());
}
private void SendUnfragmentedSessionConfirmed()
{
var ri = new BufLen(Session.MyRouterContext.MyRouterInfo.ToByteArray());
SendMessage(
SSUHeader.MessageTypes.SessionConfirmed,
Session.MACKey,
Session.SharedKey,
(start, writer) =>
{
writer.Write8((byte)((0 << 4) + 1));
writer.WriteFlip16((ushort)ri.Length);
writer.Write(ri);
Session.SignOnTimeA = BufUtils.Flip32(SSUHost.SSUTime(DateTime.UtcNow));
writer.Write32(Session.SignOnTimeA);
var padding = BufUtils.Get16BytePadding(Session.MyRouterContext.Certificate.SignatureLength + (writer - start));
writer.Write(BufUtils.RandomBytes(padding));
var baddr = new BufLen(Session.RemoteEP.Address.GetAddressBytes());
var bport = BufUtils.Flip16BL((ushort)Session.RemoteEP.Port);
#if LOG_MUCH_TRANSPORT
Logging.LogTransport($"SSU {this}: X for signature {Request.X.Key}.");
Logging.LogTransport($"SSU {this}: Y for signature {Request.Y.Key}.");
Logging.LogTransport($"SSU {this}: Alice address for signature {Request.SCMessage.Address}. Port {Request.SCMessage.Port}.");
Logging.LogTransport($"SSU {this}: Bob address for signature {baddr}. Port {bport}.");
Logging.LogTransport($"SSU {this}: Relay tag {Request.SCMessage.RelayTag}. Signon time {(BufLen)Session.SignOnTimeA}.");
#endif
var sign = I2PSignature.DoSign(Session.MyRouterContext.PrivateSigningKey,
Request.X.Key, Request.Y.Key,
Request.SCMessage.Address, Request.SCMessage.Port,
baddr, bport,
Request.SCMessage.RelayTag, BufUtils.To32BL(Session.SignOnTimeA)
);
writer.Write(sign);
Logging.LogTransport($"SSU {this}: {Session.RemoteEP} " +
$"sending unfragmented SessionConfirmed [0x{writer - start - SSUHeader.FIXED_HEADER_SIZE:X}] bytes.");
return(true);
});
}
internal static byte[] Send(DHHandshakeContext context)
{
var msglen = RouterContext.Inst.MyRouterIdentity.Certificate.SignatureLength;
msglen += BufUtils.Get16BytePadding(msglen);
var writer = new BufRefLen(new byte[msglen]);
var SigBuf = I2PSignature.DoSign(RouterContext.Inst.PrivateSigningKey,
context.XBuf,
context.YBuf,
context.RemoteRI.IdentHash.Hash,
(BufLen)BufUtils.Flip32(context.TimestampA),
(BufLen)BufUtils.Flip32(context.TimestampB));
writer.Write(SigBuf);
writer.Write(BufUtils.Random(writer.Length));
writer.Reset();
context.Encryptor.ProcessBytes((BufLen)writer);
return(writer.ToByteArray());
}
private void SendSessionCreated()
{
SendMessage(
SSUHeader.MessageTypes.SessionCreated,
Session.MyRouterContext.IntroKey,
Session.MyRouterContext.IntroKey,
(start, writer) =>
{
writer.Write(Y.Key);
AAddr = Session.RemoteEP.Address.GetAddressBytes();
writer.Write8((byte)AAddr.Length);
writer.Write(AAddr);
APort = BufUtils.Flip16((ushort)Session.RemoteEP.Port);
writer.Write16(APort);
writer.WriteFlip32(RelayTag);
Session.SignOnTimeB = BufUtils.Flip32(SSUHost.SSUTime(DateTime.UtcNow));
writer.Write32(Session.SignOnTimeB);
var sign = I2PSignature.DoSign(Session.MyRouterContext.PrivateSigningKey,
Request.X, Y.Key,
new BufLen(AAddr), (BufLen)APort,
Request.Address, (BufLen)BufUtils.Flip16((ushort)Session.MyRouterContext.UDPPort),
(BufLen)RelayTag, (BufLen)Session.SignOnTimeB);
var signstart = new BufLen(writer);
writer.Write(sign);
var padding = BufUtils.Get16BytePadding(writer - signstart);
writer.Write(BufUtils.Random(padding));
var cipher = new CbcBlockCipher(new AesEngine());
var signcryptbuf = new BufLen(signstart, 0, writer - signstart);
cipher.Init(true, Session.SharedKey.ToParametersWithIV(new BufLen(start, 16, 16)));
cipher.ProcessBytes(signcryptbuf);
return(true);
});
}
private void SendFragmentedSessionConfirmed()
{
var ri = new BufLen(Session.MyRouterContext.MyRouterInfo.ToByteArray());
var rireader = new BufRefLen(ri);
var datafragments = new List <BufLen>();
while (rireader.Length > 0)
{
datafragments.Add(rireader.ReadBufLen(Math.Min(rireader.Length, 472)));
}
for (int i = 0; i < datafragments.Count; ++i)
{
#if LOG_ALL_TRANSPORT
Logging.LogTransport(string.Format("SessionConfirmedState {0}: sending fragment {1} of {2}, {3} bytes [0x{3:X}].",
Session.DebugId,
i + 1,
datafragments.Count + 1,
datafragments[i].Length));
#endif
SendMessage(
SSUHeader.MessageTypes.SessionConfirmed,
Session.MACKey,
Session.SharedKey,
(start, writer) =>
{
writer.Write8((byte)((i << 4) + datafragments.Count + 1));
writer.WriteFlip16((ushort)datafragments[i].Length);
writer.Write(datafragments[i]);
return(true);
});
}
SendMessage(
SSUHeader.MessageTypes.SessionConfirmed,
Session.MACKey,
Session.SharedKey,
(start, writer) =>
{
var frag = datafragments.Count;
writer.Write8((byte)((frag << 4) + frag + 1));
writer.WriteFlip16(0);
Session.SignOnTimeA = BufUtils.Flip32(SSUHost.SSUTime(DateTime.UtcNow));
writer.Write32(Session.SignOnTimeA);
var padding = BufUtils.Get16BytePadding(Session.MyRouterContext.Certificate.SignatureLength + (writer - start));
writer.Write(BufUtils.Random(padding));
var baddr = new BufLen(Session.RemoteEP.Address.GetAddressBytes());
var sign = I2PSignature.DoSign(Session.MyRouterContext.PrivateSigningKey,
Request.X.Key, Request.Y.Key,
Request.SCMessage.Address, Request.SCMessage.Port,
baddr, BufUtils.Flip16BL((ushort)Session.RemoteEP.Port),
Request.SCMessage.RelayTag, (BufLen)Session.SignOnTimeA
);
writer.Write(sign);
#if LOG_ALL_TRANSPORT
Logging.LogTransport(string.Format("SessionConfirmedState {0}: sending fragment {1} of {2}, {3} bytes [0x{3:X}].",
Session.DebugId,
frag + 1,
datafragments.Count + 1,
writer - start - SSUHeader.FIXED_HEADER_SIZE));
#endif
return(true);
});
}
public override SSUState HandleMessage(SSUHeader header, BufRefLen reader)
{
var tstime = SSUHost.SSUDateTime(header.TimeStamp);
if (header.MessageType != SSUHeader.MessageTypes.SessionCreated)
{
#if LOG_ALL_TRANSPORT
Logging.LogTransport("SSU SessionRequestState: Received unexpected message " + tstime.ToString() + " : " + header.Flag.ToString());
#endif
return(this);
}
SCMessage = new SessionCreated(reader, Session.RemoteRouter.Certificate);
Session.RelayTag = SCMessage.RelayTag;
Y = new I2PPublicKey((BufRefLen)SCMessage.Y, Session.RemoteRouter.Certificate);
BufUtils.DHI2PToSessionAndMAC(out Session.SharedKey, out Session.MACKey,
Y.ToBigInteger().ModPow(PrivateKey.ToBigInteger(), I2PConstants.ElGamalP));
var ipaddr = new IPAddress(SCMessage.Address.ToByteArray());
ushort port = SCMessage.Port.PeekFlip16(0);
Session.SignOnTimeB = SCMessage.SignOnTime.Peek32(0);
var btime = SSUHost.SSUDateTime(BufUtils.Flip32(Session.SignOnTimeB));
#if LOG_ALL_TRANSPORT
Logging.LogTransport("SSU SessionRequestState " + Session.DebugId + " : Received SessionCreated. " + tstime.ToString() + " : " + btime.ToString());
#endif
Session.Host.ReportedAddress(ipaddr);
if (!I2PSignature.SupportedSignatureType(Session.RemoteRouter.Certificate.SignatureType))
{
throw new SignatureCheckFailureException("SSU SessionRequestState " + Session.DebugId + " : " +
"Received non supported signature type: " +
Session.RemoteRouter.Certificate.SignatureType.ToString());
}
var cipher = new CbcBlockCipher(new AesEngine());
cipher.Init(false, Session.SharedKey.ToParametersWithIV(header.IV));
cipher.ProcessBytes(SCMessage.SignatureEncrBuf);
var baddr = new BufLen(Session.RemoteEP.Address.GetAddressBytes());
var sign = new I2PSignature((BufRefLen)SCMessage.Signature, Session.RemoteRouter.Certificate);
var sok = I2PSignature.DoVerify(
Session.RemoteRouter.SigningPublicKey, sign,
X.Key, Y.Key,
SCMessage.Address, SCMessage.Port,
baddr, BufUtils.Flip16BL((ushort)Session.RemoteEP.Port),
SCMessage.RelayTag, SCMessage.SignOnTime);
#if LOG_ALL_TRANSPORT
Logging.LogTransport("SSU SessionRequestState: Signature check: " + sok.ToString() + ". " + Session.RemoteRouter.Certificate.SignatureType.ToString());
#endif
if (!sok)
{
throw new SignatureCheckFailureException("SSU SessionRequestState " + Session.DebugId + ": Received SessionCreated signature check failed." +
Session.RemoteRouter.Certificate.ToString());
}
var relaytag = SCMessage.RelayTag.PeekFlip32(0);
if (relaytag != 0)
{
Session.Host.IntroductionRelayOffered(
new IntroducerInfo(
Session.RemoteEP.Address,
(ushort)Session.RemoteEP.Port,
Session.IntroKey, relaytag));
}
Logging.LogTransport("SSU SessionRequestState: Session " + Session.DebugId + " created. Moving to SessionConfirmedState.");
Session.ReportConnectionEstablished();
return(new SessionConfirmedState(Session, this));
}
private void SendFragmentedSessionConfirmed()
{
var ri = new BufLen(Session.MyRouterContext.MyRouterInfo.ToByteArray());
var rireader = new BufRefLen(ri);
var datafragments = new List <BufLen>();
while (rireader.Length > 0)
{
datafragments.Add(rireader.ReadBufLen(Math.Min(rireader.Length, 472)));
}
for (int i = 0; i < datafragments.Count; ++i)
{
Logging.LogTransport($"SSU {this}: {Session.RemoteEP} " +
$"sending fragment {i + 1} of {datafragments.Count + 1}, [0x{datafragments[i].Length:X}] bytes.");
SendMessage(
SSUHeader.MessageTypes.SessionConfirmed,
Session.MACKey,
Session.SharedKey,
(start, writer) =>
{
writer.Write8((byte)((i << 4) + datafragments.Count + 1));
writer.WriteFlip16((ushort)datafragments[i].Length);
writer.Write(datafragments[i]);
return(true);
});
}
SendMessage(
SSUHeader.MessageTypes.SessionConfirmed,
Session.MACKey,
Session.SharedKey,
(start, writer) =>
{
var frag = datafragments.Count;
writer.Write8((byte)((frag << 4) + frag + 1));
writer.WriteFlip16(0);
Session.SignOnTimeA = BufUtils.Flip32(SSUHost.SSUTime(DateTime.UtcNow));
writer.Write32(Session.SignOnTimeA);
var padding = BufUtils.Get16BytePadding(Session.MyRouterContext.Certificate.SignatureLength + (writer - start));
writer.Write(BufUtils.RandomBytes(padding));
var baddr = new BufLen(Session.RemoteEP.Address.GetAddressBytes());
var sign = I2PSignature.DoSign(Session.MyRouterContext.PrivateSigningKey,
Request.X.Key, Request.Y.Key,
Request.SCMessage.Address, Request.SCMessage.Port,
baddr, BufUtils.Flip16BL((ushort)Session.RemoteEP.Port),
Request.SCMessage.RelayTag, BufUtils.To32BL(Session.SignOnTimeA)
);
writer.Write(sign);
Logging.LogTransport($"SSU {this}: {Session.RemoteEP} " +
$"sending fragment {frag + 1} of {datafragments.Count + 1}, [0x{writer - start - SSUHeader.FIXED_HEADER_SIZE:X}] bytes.");
return(true);
});
}