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public static GetRandomInt ( |
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| minValue | ||
| maxValue | ||
| return | ||
public void SampleTest()
{
Console.WriteLine("--> " + System.Reflection.MethodBase.GetCurrentMethod().Name);
int initRandomNumber = Crypto.GetRandomInt();
Console.WriteLine("Random int = " + initRandomNumber + ".");
Console.WriteLine("-----------------------------------------");
}
public static UdpClient CreateRandomUDPListener(IPAddress localAddress, int start, int end, ArrayList inUsePorts, out IPEndPoint localEndPoint)
{
try
{
UdpClient randomClient = null;
int attempts = 1;
localEndPoint = null;
while (attempts < 50)
{
int port = Crypto.GetRandomInt(start, end);
if (inUsePorts == null || !inUsePorts.Contains(port))
{
try
{
localEndPoint = new IPEndPoint(localAddress, port);
randomClient = new UdpClient(localEndPoint);
break;
}
catch
{
//logger.LogWarning("Warning couldn't create UDP end point for " + localAddress + ":" + port + "." + excp.Message);
}
attempts++;
}
}
//logger.LogDebug("Attempts to create UDP end point for " + localAddress + ":" + port + " was " + attempts);
return(randomClient);
}
catch
{
throw new ApplicationException("Unable to create a random UDP listener between " + start + " and " + end);
}
}
/// <summary>
/// Attempts to create and bind a new RTP, and optionally an control (RTCP), socket(s) within a specified port range.
/// The RTP and control sockets created are IPv4 and IPv6 dual mode sockets which means they can send and receive
/// either IPv4 or IPv6 packets.
/// </summary>
/// <param name="rangeStartPort">The start of the port range that the sockets should be created within.</param>
/// <param name="rangeEndPort">The end of the port range that the sockets should be created within.</param>
/// <param name="startPort">A port within the range indicated by the start and end ports to attempt to
/// bind the new socket(s) on. The main purpose of this parameter is to provide a pseudo-random way to allocate
/// the port for a new RTP socket.</param>
/// <param name="createControlSocket">True if a control (RTCP) socket should be created. Set to false if RTP
/// and RTCP are being multiplexed on the same connection.</param>
/// <param name="localAddress">Optional. If null The RTP and control sockets will be created as IPv4 and IPv6 dual mode
/// sockets which means they can send and receive either IPv4 or IPv6 packets. If the local address is specified an attempt
/// will be made to bind the RTP and optionally control listeners on it.</param>
/// <param name="rtpSocket">An output parameter that will contain the allocated RTP socket.</param>
/// <param name="controlSocket">An output parameter that will contain the allocated control (RTCP) socket.</param>
public static void CreateRtpSocket(int rangeStartPort, int rangeEndPort, int startPort, bool createControlSocket, IPAddress localAddress, out Socket rtpSocket, out Socket controlSocket)
{
if (startPort == 0)
{
startPort = Crypto.GetRandomInt(rangeStartPort, rangeEndPort);
}
else if (startPort < rangeStartPort || startPort > rangeEndPort)
{
logger.LogWarning($"The start port of {startPort} supplied to CreateRtpSocket was outside the request range of {rangeStartPort}:{rangeEndPort}. A new valid start port will be pseudo-randomly chosen.");
startPort = Crypto.GetRandomInt(rangeStartPort, rangeEndPort);
}
logger.LogDebug($"CreateRtpSocket start port {startPort}, range {rangeStartPort}:{rangeEndPort}.");
rtpSocket = null;
controlSocket = null;
bool bindSuccess = false;
int rtpPort = startPort;
// Attempt to adjust the start port for:
// - If in use ports can be checked find the first even unused port,
// - Otherwise if not even then set to the nearest even port.
if (Environment.OSVersion.Platform == PlatformID.Win32NT)
{
// On Windows we can get a list of in use UDP ports and avoid attempting to bind to them.
IPGlobalProperties ipGlobalProperties = IPGlobalProperties.GetIPGlobalProperties();
var udpListeners = ipGlobalProperties.GetActiveUdpListeners();
var portRange = Enumerable.Range(rangeStartPort, rangeEndPort - rangeStartPort).OrderBy(x => (x > startPort) ? x : x + rangeEndPort);
var inUsePorts = udpListeners.Where(x => x.Port >= rangeStartPort && x.Port <= rangeEndPort).Select(x => x.Port);
logger.LogDebug($"In use UDP ports count {inUsePorts.Count()}.");
rtpPort = portRange.Except(inUsePorts).Where(x => x % 2 == 0).FirstOrDefault();
}
else
{
// If the start port isn't even adjust it so it is. The original RTP specification required RTP ports to be even
// numbered and the control port to be the RTP port + 1.
if (rtpPort % 2 != 0)
{
rtpPort = (rtpPort + 1) > rangeEndPort ? rtpPort - 1 : rtpPort + 1;
}
}
for (int bindAttempts = 0; bindAttempts <= MAXIMUM_RTP_PORT_BIND_ATTEMPTS; bindAttempts++)
{
//lock (_allocatePortsMutex)
//{
int controlPort = (createControlSocket == true) ? rtpPort + 1 : 0;
try
{
// The potential ports have been found now try and use them.
if (localAddress != null)
{
rtpSocket = new Socket(localAddress.AddressFamily, SocketType.Dgram, ProtocolType.Udp);
rtpSocket.ReceiveBufferSize = RTP_RECEIVE_BUFFER_SIZE;
rtpSocket.SendBufferSize = RTP_SEND_BUFFER_SIZE;
rtpSocket.Bind(new IPEndPoint(localAddress, rtpPort));
}
else
{
// Create a dual mode IPv4/IPv6 socket.
rtpSocket = new Socket(SocketType.Dgram, ProtocolType.Udp);
rtpSocket.ReceiveBufferSize = RTP_RECEIVE_BUFFER_SIZE;
rtpSocket.SendBufferSize = RTP_SEND_BUFFER_SIZE;
var bindAddress = (Socket.OSSupportsIPv6) ? IPAddress.IPv6Any : IPAddress.Any;
rtpSocket.Bind(new IPEndPoint(bindAddress, rtpPort));
}
if (controlPort != 0)
{
if (localAddress != null)
{
controlSocket = new Socket(localAddress.AddressFamily, SocketType.Dgram, ProtocolType.Udp);
controlSocket.Bind(new IPEndPoint(localAddress, controlPort));
}
else
{
// Create a dual mode IPv4/IPv6 socket.
controlSocket = new Socket(SocketType.Dgram, ProtocolType.Udp);
var bindAddress = (Socket.OSSupportsIPv6) ? IPAddress.IPv6Any : IPAddress.Any;
controlSocket.Bind(new IPEndPoint(bindAddress, controlPort));
}
logger.LogDebug($"Successfully bound RTP socket {rtpSocket.LocalEndPoint} and control socket {controlSocket.LocalEndPoint}.");
}
else
{
logger.LogDebug($"Successfully bound RTP socket {rtpSocket.LocalEndPoint}.");
}
bindSuccess = true;
break;
}
catch (SocketException sockExcp)
{
if (sockExcp.SocketErrorCode != SocketError.AddressAlreadyInUse)
{
if (controlPort != 0)
{
logger.LogWarning($"Socket error {sockExcp.ErrorCode} binding to address {localAddress} and RTP port {rtpPort} and/or control port of {controlPort}, attempt {bindAttempts}.");
}
else
{
logger.LogWarning($"Socket error {sockExcp.ErrorCode} binding to address {localAddress} and RTP port {rtpPort}, attempt {bindAttempts}.");
}
}
else
{
logger.LogWarning($"SocketException in NetServices.CreateRtpSocket. {sockExcp}");
}
}
catch (Exception excp)
{
logger.LogWarning($"Exception in NetServices.CreateRtpSocket. {excp}");
}
// Adjust the start port for the next attempt.
int step = Crypto.GetRandomInt(RTP_STEP_MIN, RTP_STEM_MAX);
step = (step % 2 == 0) ? step : step + 1;
rtpPort = (rtpPort + step + 1) > rangeEndPort ? rangeStartPort + step : rtpPort + step;
//}
}
if (!bindSuccess)
{
throw new ApplicationException($"RTP socket allocation failure range {rangeStartPort}:{rangeEndPort}.");
}
}
