public static async void WsTraceRoute(HttpListenerContext ctx)
{
WebSocketContext wsc;
WebSocket ws;
try {
wsc = await ctx.AcceptWebSocketAsync(null);
ws = wsc.WebSocket;
} catch (WebSocketException ex) {
ctx.Response.Close();
Logging.Err(ex);
return;
}
string sessionId = ctx.Request.Cookies["sessionid"]?.Value ?? null;
if (sessionId is null)
{
ctx.Response.Close();
return;
}
object send_lock = new object();
try {
while (ws.State == WebSocketState.Open)
{
byte[] buff = new byte[2048];
WebSocketReceiveResult receiveResult = await ws.ReceiveAsync(new ArraySegment <byte>(buff), CancellationToken.None);
if (!Session.CheckAccess(sessionId)) //check session
{
ctx.Response.Close();
return;
}
if (receiveResult.MessageType == WebSocketMessageType.Close)
{
await ws.CloseAsync(WebSocketCloseStatus.NormalClosure, "", CancellationToken.None);
break;
}
string hostname = Encoding.Default.GetString(buff, 0, receiveResult.Count);
hostname = hostname.Trim();
if (hostname.Length == 0)
{
await ws.SendAsync(Strings.INV, WebSocketMessageType.Text, true, CancellationToken.None);
continue;
}
const short timeout = 2000; //2s
const short ttl = 30;
List <string> list = new List <string>();
new Thread(async() => {
List <IPAddress> ipList = new List <IPAddress>();
string lastAddress = "";
using (System.Net.NetworkInformation.Ping p = new System.Net.NetworkInformation.Ping())
for (short i = 1; i < ttl; i++)
{
if (ws.State != WebSocketState.Open)
{
break;
}
string result = $"{hostname}{(char)127}";
try {
PingReply reply = p.Send(hostname, timeout, TRACE_ROUTE_BUFFER, new PingOptions(i, true));
if (reply.Status == IPStatus.Success || reply.Status == IPStatus.TtlExpired)
{
if (lastAddress == reply.Address.ToString())
{
break;
}
else
{
lastAddress = reply.Address.ToString();
}
result += $"{reply.Address}{(char)127}{reply.RoundtripTime}";
ipList.Add(reply.Address);
}
else if (reply.Status == IPStatus.TimedOut)
{
result += "Timed Out";
}
else
{
break;
}
} catch (Exception ex) {
Logging.Err(ex);
break;
}
lock (send_lock) //once send per socket
ws.SendAsync(new ArraySegment <byte>(Encoding.UTF8.GetBytes(result), 0, result.Length), WebSocketMessageType.Text, true, CancellationToken.None);
}
List <Task <string> > tasks = new List <Task <string> >();
for (int j = 0; j < ipList.Count; j++)
{
tasks.Add(Dns.DnsLookupAsync(ipList[j]));
}
string[] hostnameArray = await Task.WhenAll(tasks);
string hostnames = $"[hostnames]{(char)127}{hostname}{(char)127}";
for (int i = 0; i < hostnameArray.Length; i++)
{
if (hostnameArray[i].Length > 0 && hostnameArray[i] != ipList[i].ToString())
{
hostnames += $"{ipList[i]}{(char)127}{hostnameArray[i]}{(char)127}";
}
}
if (hostnames.EndsWith(((char)127).ToString()))
{
hostnames = hostnames.Substring(0, hostnames.Length - 1);
}
lock (send_lock) {
ws.SendAsync(new ArraySegment <byte>(Encoding.UTF8.GetBytes(hostnames), 0, hostnames.Length), WebSocketMessageType.Text, true, CancellationToken.None);
string over = "over" + ((char)127).ToString() + hostname;
ws.SendAsync(new ArraySegment <byte>(Encoding.UTF8.GetBytes(over), 0, over.Length), WebSocketMessageType.Text, true, CancellationToken.None);
}
}).Start();
}
} catch (Exception ex) {
Logging.Err(ex);
}
}
