public void ScanAsync(IPAddress[] ipAddresses, CancellationToken cancellationToken)
{
// Start the scan in a separat task
Task.Run(() =>
{
_progressValue = 0;
// Create dns client and set options
if (ResolveHostname)
{
DnsLookupClient = UseCustomDNSServer ? new LookupClient(new IPEndPoint(CustomDNSServer, CustomDNSPort)) : new LookupClient();
DnsLookupClient.UseCache = DNSUseCache;
DnsLookupClient.Recursion = DNSRecursion;
DnsLookupClient.Timeout = DNSTimeout;
DnsLookupClient.Retries = DNSRetries;
DnsLookupClient.UseTcpOnly = DNSUseTCPOnly;
}
// Modify the ThreadPool for better performance
ThreadPool.GetMinThreads(out var workerThreads, out var completionPortThreads);
ThreadPool.SetMinThreads(workerThreads + Threads, completionPortThreads + Threads);
try
{
var parallelOptions = new ParallelOptions
{
CancellationToken = cancellationToken,
MaxDegreeOfParallelism = Threads
};
Parallel.ForEach(ipAddresses, parallelOptions, ipAddress =>
{
var pingInfo = new PingInfo();
var pingable = false;
// PING
using (var ping = new System.Net.NetworkInformation.Ping())
{
for (var i = 0; i < ICMPAttempts; i++)
{
try
{
var pingReply = ping.Send(ipAddress, ICMPTimeout, ICMPBuffer);
if (pingReply != null && IPStatus.Success == pingReply.Status)
{
if (ipAddress.AddressFamily == System.Net.Sockets.AddressFamily.InterNetwork)
{
pingInfo = new PingInfo(pingReply.Address, pingReply.Buffer.Length, pingReply.RoundtripTime, pingReply.Options.Ttl, pingReply.Status);
}
else
{
pingInfo = new PingInfo(pingReply.Address, pingReply.Buffer.Length, pingReply.RoundtripTime, pingReply.Status);
}
pingable = true;
break; // Continue with the next checks...
}
if (pingReply != null)
{
pingInfo = new PingInfo(ipAddress, pingReply.Status);
}
}
catch (PingException)
{ }
// Don't scan again, if the user has canceled (when more than 1 attempt)
if (cancellationToken.IsCancellationRequested)
{
break;
}
}
}
if (pingable || ShowScanResultForAllIPAddresses)
{
// DNS
var hostname = string.Empty;
if (ResolveHostname)
{
try
{
var dnsQueryResponse = DnsLookupClient.QueryReverse(ipAddress);
if (dnsQueryResponse != null && !dnsQueryResponse.HasError)
{
hostname = dnsQueryResponse.Answers.PtrRecords().FirstOrDefault()?.PtrDomainName;
}
else
{
hostname = DNSShowErrorMessage ? dnsQueryResponse.ErrorMessage : "";
}
}
catch (Exception ex)
{
hostname = DNSShowErrorMessage ? ex.Message : "";
}
}
// ARP
PhysicalAddress macAddress = null;
var vendor = string.Empty;
if (ResolveMACAddress)
{
// Get info from arp table
var arpTableInfo = ARP.GetTable().FirstOrDefault(p => p.IPAddress.ToString() == ipAddress.ToString());
if (arpTableInfo != null)
{
macAddress = arpTableInfo.MACAddress;
}
// Check if it is the local mac
if (macAddress == null)
{
var networkInferfaceInfo = NetworkInterface.GetNetworkInterfaces().FirstOrDefault(p => p.IPv4Address.Contains(ipAddress));
if (networkInferfaceInfo != null)
{
macAddress = networkInferfaceInfo.PhysicalAddress;
}
}
// Vendor lookup
if (macAddress != null)
{
var info = OUILookup.Lookup(macAddress.ToString()).FirstOrDefault();
if (info != null)
{
vendor = info.Vendor;
}
}
}
OnHostFound(new HostFoundArgs(pingInfo, hostname, macAddress, vendor));
}
IncreaseProcess();
});
OnScanComplete();
}
catch (OperationCanceledException) // If user has canceled
{
// Check if the scan is already complete...
if (ipAddresses.Length == _progressValue)
{
OnScanComplete();
}
else
{
OnUserHasCanceled();
}
}
finally
{
// Reset the ThreadPool to default
ThreadPool.GetMinThreads(out workerThreads, out completionPortThreads);
ThreadPool.SetMinThreads(workerThreads - Threads, completionPortThreads - Threads);
}
}, cancellationToken);
}