/// <summary>
/// Sends a contact request to the specified Bluetooth device.
/// </summary>
/// <param name="device">The device to send the request to.</param>
/// <param name="myAddress">The local address to send to the device.</param>
/// <returns>The Erebus address of the device if the request was accepted; otherwise null.</returns>
public static ErebusAddress?RequestAddContact(RfcommDeviceService device, ErebusAddress myAddress)
{
Log.RecordEvent(typeof(BluetoothUtils), $"Attempting to add Bluetooth device '{device.ConnectionHostName.CanonicalName}' as a contact.", LogEntrySeverity.Info);
try
{
var socket = new StreamSocket();
new Func <Task>(async() =>
{
await socket.ConnectAsync(device.ConnectionHostName, RfcommAddContactService.AsString(), SocketProtectionLevel.BluetoothEncryptionWithAuthentication);
})().Wait();
using (var r = new BinaryReader(socket.InputStream.AsStreamForRead()))
using (var w = new BinaryWriter(socket.OutputStream.AsStreamForWrite()))
{
w.Write(myAddress);
var addr = r.ReadErebusAddress();
var vkp = PlatformServiceProvider.Create("VerificationKeyProvider");
var local = vkp.CreatePrivateKey();
w.Write(local.Item2.Length);
w.Write(local.Item2);
vkp.AddKeyPair(addr, local.Item1, r.ReadBytes(r.ReadInt32()));
Log.RecordEvent(typeof(BluetoothUtils), $"Successfully negotiated contact with {addr} via Bluetooth RFCOMM.", LogEntrySeverity.Info);
return(addr);
}
}
catch (Exception e)
{
Log.RecordEvent(typeof(BluetoothUtils), $"Exception adding contact: {e.Message}; assuming other user rejected request.", LogEntrySeverity.Error);
return(null);
}
}
void retrieveKeys(ErebusAddress other)
{
var keys = PlatformServiceProvider.Create("VerificationKeyProvider").GetKeyPair(other);
myKey = keys.Item1;
otherKey = keys.Item2;
}
bool core(ErebusAddress addr, bool request, Guid id, byte[] otherKey, Predicate <int> pinCheck)
{
var vkp = PlatformServiceProvider.Create("VerificationKeyProvider");
var k = vkp.CreatePrivateKey();
byte[] lp = k.Item2;
using (var ewh = new EventWaitHandle(false, EventResetMode.ManualReset))
{
bool l = false, r = false;
lock (arh)
arh[id] = a =>
{
r = a;
ewh.Set();
lock (arh)
arh.Remove(id);
};
if (request)
{
using (var kewh = new EventWaitHandle(false, EventResetMode.ManualReset))
{
lock (hrh)
hrh[id] = _k =>
{
otherKey = _k;
kewh.Set();
};
SendPacket(new ErebusEndpoint(addr, 1), new byte[] { 0 }.Concat(id.ToByteArray()).Concat(lp).ToArray());
kewh.WaitOne();
}
}
else
{
SendPacket(new ErebusEndpoint(addr, 1), new byte[] { 1 }.Concat(id.ToByteArray()).Concat(lp).ToArray());
}
var hash = WinRTCrypto.HashAlgorithmProvider.OpenAlgorithm(HashAlgorithm.Sha512).HashData((request ? lp.Concat(otherKey) : otherKey.Concat(lp)).ToArray());
for (int i = 4; i < hash.Length; ++i)
{
hash[i % 4] ^= hash[i];
}
l = pinCheck(BitConverter.ToInt32(hash, 0));
SendPacket(new ErebusEndpoint(addr, 1), new[] { (byte)(l ? 2 : 3) }.Concat(id.ToByteArray()).ToArray());
if (l)
{
ewh.WaitOne();
if (r)
{
vkp.AddKeyPair(addr, k.Item1, otherKey);
return(true);
}
}
}
return(false);
}
Task listenProcess() => Task.Run(async() =>
{
var p = await RfcommServiceProvider.CreateAsync(BluetoothUtils.RfcommAddContactService);
using (var l = new StreamSocketListener())
{
l.ConnectionReceived += (sender, e) =>
{
using (var r = new BinaryReader(e.Socket.InputStream.AsStreamForRead()))
using (var w = new BinaryWriter(e.Socket.OutputStream.AsStreamForWrite()))
{
w.Write(true);
r.ReadBoolean();
var _addr = r.ReadErebusAddress();
if (h(_addr, e.Socket.Information.RemoteHostName.DisplayName))
{
w.Write(addr);
var vkp = PlatformServiceProvider.Create("VerificationKeyProvider");
var local = vkp.CreatePrivateKey();
w.Write(local.Item2.Length);
w.Write(local.Item2);
vkp.AddKeyPair(addr, local.Item1, r.ReadBytes(r.ReadInt32()));
Log.RecordEvent(this, $"Successfully negotiated contact with {_addr} via Bluetooth RFCOMM.", LogEntrySeverity.Info);
}
}
};
await l.BindServiceNameAsync(BluetoothUtils.RfcommAddContactService.AsString(), SocketProtectionLevel.BluetoothEncryptionWithAuthentication);
using (var w = new DataWriter())
{
w.WriteByte(37);
var name = "Erebus Contact Request Service";
w.WriteByte((byte)name.Length);
w.UnicodeEncoding = UnicodeEncoding.Utf8;
w.WriteString(name);
p.SdpRawAttributes.Add(0x100, w.DetachBuffer());
}
p.StartAdvertising(l);
while (process)
{
await Task.Delay(10);
}
p.StopAdvertising();
}
});