jellyfin/RSSDP/SsdpDevicePublisher.cs
2018-09-12 19:26:21 +02:00

561 lines
24 KiB
C#

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Net.Http;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using MediaBrowser.Model.Net;
using MediaBrowser.Model.Threading;
using Rssdp;
namespace Rssdp.Infrastructure
{
/// <summary>
/// Provides the platform independent logic for publishing SSDP devices (notifications and search responses).
/// </summary>
public class SsdpDevicePublisher : DisposableManagedObjectBase, ISsdpDevicePublisher
{
private ISsdpCommunicationsServer _CommsServer;
private string _OSName;
private string _OSVersion;
private bool _SupportPnpRootDevice;
private IList<SsdpRootDevice> _Devices;
private IReadOnlyList<SsdpRootDevice> _ReadOnlyDevices;
private ITimer _RebroadcastAliveNotificationsTimer;
private ITimerFactory _timerFactory;
private IDictionary<string, SearchRequest> _RecentSearchRequests;
private Random _Random;
private const string ServerVersion = "1.0";
/// <summary>
/// Default constructor.
/// </summary>
public SsdpDevicePublisher(ISsdpCommunicationsServer communicationsServer, ITimerFactory timerFactory, string osName, string osVersion)
{
if (communicationsServer == null) throw new ArgumentNullException("communicationsServer");
if (osName == null) throw new ArgumentNullException("osName");
if (osName.Length == 0) throw new ArgumentException("osName cannot be an empty string.", "osName");
if (osVersion == null) throw new ArgumentNullException("osVersion");
if (osVersion.Length == 0) throw new ArgumentException("osVersion cannot be an empty string.", "osName");
_SupportPnpRootDevice = true;
_timerFactory = timerFactory;
_Devices = new List<SsdpRootDevice>();
_ReadOnlyDevices = new ReadOnlyCollection<SsdpRootDevice>(_Devices);
_RecentSearchRequests = new Dictionary<string, SearchRequest>(StringComparer.OrdinalIgnoreCase);
_Random = new Random();
_CommsServer = communicationsServer;
_CommsServer.RequestReceived += CommsServer_RequestReceived;
_OSName = osName;
_OSVersion = osVersion;
_CommsServer.BeginListeningForBroadcasts();
}
public void StartBroadcastingAliveMessages(TimeSpan interval)
{
_RebroadcastAliveNotificationsTimer = _timerFactory.Create(SendAllAliveNotifications, null, TimeSpan.FromSeconds(5), interval);
}
/// <summary>
/// Adds a device (and it's children) to the list of devices being published by this server, making them discoverable to SSDP clients.
/// </summary>
/// <remarks>
/// <para>Adding a device causes "alive" notification messages to be sent immediately, or very soon after. Ensure your device/description service is running before adding the device object here.</para>
/// <para>Devices added here with a non-zero cache life time will also have notifications broadcast periodically.</para>
/// <para>This method ignores duplicate device adds (if the same device instance is added multiple times, the second and subsequent add calls do nothing).</para>
/// </remarks>
/// <param name="device">The <see cref="SsdpDevice"/> instance to add.</param>
/// <exception cref="System.ArgumentNullException">Thrown if the <paramref name="device"/> argument is null.</exception>
/// <exception cref="System.InvalidOperationException">Thrown if the <paramref name="device"/> contains property values that are not acceptable to the UPnP 1.0 specification.</exception>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1804:RemoveUnusedLocals", MessageId = "t", Justification = "Capture task to local variable supresses compiler warning, but task is not really needed.")]
public void AddDevice(SsdpRootDevice device)
{
if (device == null) throw new ArgumentNullException("device");
ThrowIfDisposed();
TimeSpan minCacheTime = TimeSpan.Zero;
bool wasAdded = false;
lock (_Devices)
{
if (!_Devices.Contains(device))
{
_Devices.Add(device);
wasAdded = true;
minCacheTime = GetMinimumNonZeroCacheLifetime();
}
}
if (wasAdded)
{
WriteTrace("Device Added", device);
SendAliveNotifications(device, true, CancellationToken.None);
}
}
/// <summary>
/// Removes a device (and it's children) from the list of devices being published by this server, making them undiscoverable.
/// </summary>
/// <remarks>
/// <para>Removing a device causes "byebye" notification messages to be sent immediately, advising clients of the device/service becoming unavailable. We recommend removing the device from the published list before shutting down the actual device/service, if possible.</para>
/// <para>This method does nothing if the device was not found in the collection.</para>
/// </remarks>
/// <param name="device">The <see cref="SsdpDevice"/> instance to add.</param>
/// <exception cref="System.ArgumentNullException">Thrown if the <paramref name="device"/> argument is null.</exception>
public async Task RemoveDevice(SsdpRootDevice device)
{
if (device == null) throw new ArgumentNullException("device");
bool wasRemoved = false;
TimeSpan minCacheTime = TimeSpan.Zero;
lock (_Devices)
{
if (_Devices.Contains(device))
{
_Devices.Remove(device);
wasRemoved = true;
minCacheTime = GetMinimumNonZeroCacheLifetime();
}
}
if (wasRemoved)
{
WriteTrace("Device Removed", device);
await SendByeByeNotifications(device, true, CancellationToken.None).ConfigureAwait(false);
}
}
/// <summary>
/// Returns a read only list of devices being published by this instance.
/// </summary>
public IEnumerable<SsdpRootDevice> Devices
{
get
{
return _ReadOnlyDevices;
}
}
/// <summary>
/// If true (default) treats root devices as both upnp:rootdevice and pnp:rootdevice types.
/// </summary>
/// <remarks>
/// <para>Enabling this option will cause devices to show up in Microsoft Windows Explorer's network screens (if discovery is enabled etc.). Windows Explorer appears to search only for pnp:rootdeivce and not upnp:rootdevice.</para>
/// <para>If false, the system will only use upnp:rootdevice for notifiation broadcasts and and search responses, which is correct according to the UPnP/SSDP spec.</para>
/// </remarks>
public bool SupportPnpRootDevice
{
get { return _SupportPnpRootDevice; }
set
{
_SupportPnpRootDevice = value;
}
}
/// <summary>
/// Stops listening for requests, stops sending periodic broadcasts, disposes all internal resources.
/// </summary>
/// <param name="disposing"></param>
protected override void Dispose(bool disposing)
{
if (disposing)
{
DisposeRebroadcastTimer();
var commsServer = _CommsServer;
if (commsServer != null)
{
commsServer.RequestReceived -= this.CommsServer_RequestReceived;
}
var tasks = Devices.ToList().Select(RemoveDevice).ToArray();
Task.WaitAll(tasks);
_CommsServer = null;
if (commsServer != null)
{
if (!commsServer.IsShared)
commsServer.Dispose();
}
_RecentSearchRequests = null;
}
}
private void ProcessSearchRequest(string mx, string searchTarget, IpEndPointInfo remoteEndPoint, IpAddressInfo receivedOnlocalIpAddress, CancellationToken cancellationToken)
{
if (String.IsNullOrEmpty(searchTarget))
{
WriteTrace(String.Format("Invalid search request received From {0}, Target is null/empty.", remoteEndPoint.ToString()));
return;
}
//WriteTrace(String.Format("Search Request Received From {0}, Target = {1}", remoteEndPoint.ToString(), searchTarget));
if (IsDuplicateSearchRequest(searchTarget, remoteEndPoint))
{
//WriteTrace("Search Request is Duplicate, ignoring.");
return;
}
//Wait on random interval up to MX, as per SSDP spec.
//Also, as per UPnP 1.1/SSDP spec ignore missing/bank MX header. If over 120, assume random value between 0 and 120.
//Using 16 as minimum as that's often the minimum system clock frequency anyway.
int maxWaitInterval = 0;
if (String.IsNullOrEmpty(mx))
{
//Windows Explorer is poorly behaved and doesn't supply an MX header value.
//if (this.SupportPnpRootDevice)
mx = "1";
//else
//return;
}
if (!Int32.TryParse(mx, out maxWaitInterval) || maxWaitInterval <= 0) return;
if (maxWaitInterval > 120)
maxWaitInterval = _Random.Next(0, 120);
//Do not block synchronously as that may tie up a threadpool thread for several seconds.
Task.Delay(_Random.Next(16, (maxWaitInterval * 1000))).ContinueWith((parentTask) =>
{
//Copying devices to local array here to avoid threading issues/enumerator exceptions.
IEnumerable<SsdpDevice> devices = null;
lock (_Devices)
{
if (String.Compare(SsdpConstants.SsdpDiscoverAllSTHeader, searchTarget, StringComparison.OrdinalIgnoreCase) == 0)
devices = GetAllDevicesAsFlatEnumerable().ToArray();
else if (String.Compare(SsdpConstants.UpnpDeviceTypeRootDevice, searchTarget, StringComparison.OrdinalIgnoreCase) == 0 || (this.SupportPnpRootDevice && String.Compare(SsdpConstants.PnpDeviceTypeRootDevice, searchTarget, StringComparison.OrdinalIgnoreCase) == 0))
devices = _Devices.ToArray();
else if (searchTarget.Trim().StartsWith("uuid:", StringComparison.OrdinalIgnoreCase))
devices = (from device in GetAllDevicesAsFlatEnumerable() where String.Compare(device.Uuid, searchTarget.Substring(5), StringComparison.OrdinalIgnoreCase) == 0 select device).ToArray();
else if (searchTarget.StartsWith("urn:", StringComparison.OrdinalIgnoreCase))
devices = (from device in GetAllDevicesAsFlatEnumerable() where String.Compare(device.FullDeviceType, searchTarget, StringComparison.OrdinalIgnoreCase) == 0 select device).ToArray();
}
if (devices != null)
{
var deviceList = devices.ToList();
//WriteTrace(String.Format("Sending {0} search responses", deviceList.Count));
foreach (var device in deviceList)
{
SendDeviceSearchResponses(device, remoteEndPoint, receivedOnlocalIpAddress, cancellationToken);
}
}
else
{
//WriteTrace(String.Format("Sending 0 search responses."));
}
});
}
private IEnumerable<SsdpDevice> GetAllDevicesAsFlatEnumerable()
{
return _Devices.Union(_Devices.SelectManyRecursive<SsdpDevice>((d) => d.Devices));
}
private void SendDeviceSearchResponses(SsdpDevice device, IpEndPointInfo endPoint, IpAddressInfo receivedOnlocalIpAddress, CancellationToken cancellationToken)
{
bool isRootDevice = (device as SsdpRootDevice) != null;
if (isRootDevice)
{
SendSearchResponse(SsdpConstants.UpnpDeviceTypeRootDevice, device, GetUsn(device.Udn, SsdpConstants.UpnpDeviceTypeRootDevice), endPoint, receivedOnlocalIpAddress, cancellationToken);
if (this.SupportPnpRootDevice)
SendSearchResponse(SsdpConstants.PnpDeviceTypeRootDevice, device, GetUsn(device.Udn, SsdpConstants.PnpDeviceTypeRootDevice), endPoint, receivedOnlocalIpAddress, cancellationToken);
}
SendSearchResponse(device.Udn, device, device.Udn, endPoint, receivedOnlocalIpAddress, cancellationToken);
SendSearchResponse(device.FullDeviceType, device, GetUsn(device.Udn, device.FullDeviceType), endPoint, receivedOnlocalIpAddress, cancellationToken);
}
private string GetUsn(string udn, string fullDeviceType)
{
return String.Format("{0}::{1}", udn, fullDeviceType);
}
private async void SendSearchResponse(string searchTarget, SsdpDevice device, string uniqueServiceName, IpEndPointInfo endPoint, IpAddressInfo receivedOnlocalIpAddress, CancellationToken cancellationToken)
{
var rootDevice = device.ToRootDevice();
//var additionalheaders = FormatCustomHeadersForResponse(device);
const string header = "HTTP/1.1 200 OK";
var values = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
values["EXT"] = "";
values["DATE"] = DateTime.UtcNow.ToString("r");
values["CACHE-CONTROL"] = "max-age = " + rootDevice.CacheLifetime.TotalSeconds;
values["ST"] = searchTarget;
values["SERVER"] = string.Format("{0}/{1} UPnP/1.0 RSSDP/{2}", _OSName, _OSVersion, ServerVersion);
values["USN"] = uniqueServiceName;
values["LOCATION"] = rootDevice.Location.ToString();
var message = BuildMessage(header, values);
try
{
await _CommsServer.SendMessage(System.Text.Encoding.UTF8.GetBytes(message), endPoint, receivedOnlocalIpAddress, cancellationToken).ConfigureAwait(false);
}
catch (Exception ex)
{
}
//WriteTrace(String.Format("Sent search response to " + endPoint.ToString()), device);
}
private bool IsDuplicateSearchRequest(string searchTarget, IpEndPointInfo endPoint)
{
var isDuplicateRequest = false;
var newRequest = new SearchRequest() { EndPoint = endPoint, SearchTarget = searchTarget, Received = DateTime.UtcNow };
lock (_RecentSearchRequests)
{
if (_RecentSearchRequests.ContainsKey(newRequest.Key))
{
var lastRequest = _RecentSearchRequests[newRequest.Key];
if (lastRequest.IsOld())
_RecentSearchRequests[newRequest.Key] = newRequest;
else
isDuplicateRequest = true;
}
else
{
_RecentSearchRequests.Add(newRequest.Key, newRequest);
if (_RecentSearchRequests.Count > 10)
CleanUpRecentSearchRequestsAsync();
}
}
return isDuplicateRequest;
}
private void CleanUpRecentSearchRequestsAsync()
{
lock (_RecentSearchRequests)
{
foreach (var requestKey in (from r in _RecentSearchRequests where r.Value.IsOld() select r.Key).ToArray())
{
_RecentSearchRequests.Remove(requestKey);
}
}
}
private void SendAllAliveNotifications(object state)
{
try
{
if (IsDisposed) return;
//WriteTrace("Begin Sending Alive Notifications For All Devices");
SsdpRootDevice[] devices;
lock (_Devices)
{
devices = _Devices.ToArray();
}
foreach (var device in devices)
{
if (IsDisposed) return;
SendAliveNotifications(device, true, CancellationToken.None);
}
//WriteTrace("Completed Sending Alive Notifications For All Devices");
}
catch (ObjectDisposedException ex)
{
WriteTrace("Publisher stopped, exception " + ex.Message);
Dispose();
}
}
private void SendAliveNotifications(SsdpDevice device, bool isRoot, CancellationToken cancellationToken)
{
if (isRoot)
{
SendAliveNotification(device, SsdpConstants.UpnpDeviceTypeRootDevice, GetUsn(device.Udn, SsdpConstants.UpnpDeviceTypeRootDevice), cancellationToken);
if (this.SupportPnpRootDevice)
SendAliveNotification(device, SsdpConstants.PnpDeviceTypeRootDevice, GetUsn(device.Udn, SsdpConstants.PnpDeviceTypeRootDevice), cancellationToken);
}
SendAliveNotification(device, device.Udn, device.Udn, cancellationToken);
SendAliveNotification(device, device.FullDeviceType, GetUsn(device.Udn, device.FullDeviceType), cancellationToken);
foreach (var childDevice in device.Devices)
{
SendAliveNotifications(childDevice, false, cancellationToken);
}
}
private void SendAliveNotification(SsdpDevice device, string notificationType, string uniqueServiceName, CancellationToken cancellationToken)
{
var rootDevice = device.ToRootDevice();
const string header = "NOTIFY * HTTP/1.1";
var values = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
// If needed later for non-server devices, these headers will need to be dynamic
values["HOST"] = "239.255.255.250:1900";
values["DATE"] = DateTime.UtcNow.ToString("r");
values["CACHE-CONTROL"] = "max-age = " + rootDevice.CacheLifetime.TotalSeconds;
values["LOCATION"] = rootDevice.Location.ToString();
values["SERVER"] = string.Format("{0}/{1} UPnP/1.0 RSSDP/{2}", _OSName, _OSVersion, ServerVersion);
values["NTS"] = "ssdp:alive";
values["NT"] = notificationType;
values["USN"] = uniqueServiceName;
var message = BuildMessage(header, values);
_CommsServer.SendMulticastMessage(message, cancellationToken);
//WriteTrace(String.Format("Sent alive notification"), device);
}
private Task SendByeByeNotifications(SsdpDevice device, bool isRoot, CancellationToken cancellationToken)
{
var tasks = new List<Task>();
if (isRoot)
{
tasks.Add(SendByeByeNotification(device, SsdpConstants.UpnpDeviceTypeRootDevice, GetUsn(device.Udn, SsdpConstants.UpnpDeviceTypeRootDevice), cancellationToken));
if (this.SupportPnpRootDevice)
tasks.Add(SendByeByeNotification(device, "pnp:rootdevice", GetUsn(device.Udn, "pnp:rootdevice"), cancellationToken));
}
tasks.Add(SendByeByeNotification(device, device.Udn, device.Udn, cancellationToken));
tasks.Add(SendByeByeNotification(device, String.Format("urn:{0}", device.FullDeviceType), GetUsn(device.Udn, device.FullDeviceType), cancellationToken));
foreach (var childDevice in device.Devices)
{
tasks.Add(SendByeByeNotifications(childDevice, false, cancellationToken));
}
return Task.WhenAll(tasks);
}
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Naming", "CA2204:Literals should be spelled correctly", MessageId = "byebye", Justification = "Correct value for this type of notification in SSDP.")]
private Task SendByeByeNotification(SsdpDevice device, string notificationType, string uniqueServiceName, CancellationToken cancellationToken)
{
const string header = "NOTIFY * HTTP/1.1";
var values = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
// If needed later for non-server devices, these headers will need to be dynamic
values["HOST"] = "239.255.255.250:1900";
values["DATE"] = DateTime.UtcNow.ToString("r");
values["SERVER"] = string.Format("{0}/{1} UPnP/1.0 RSSDP/{2}", _OSName, _OSVersion, ServerVersion);
values["NTS"] = "ssdp:byebye";
values["NT"] = notificationType;
values["USN"] = uniqueServiceName;
var message = BuildMessage(header, values);
var sendCount = IsDisposed ? 1 : 3;
WriteTrace(String.Format("Sent byebye notification"), device);
return _CommsServer.SendMulticastMessage(message, sendCount, cancellationToken);
}
private void DisposeRebroadcastTimer()
{
var timer = _RebroadcastAliveNotificationsTimer;
_RebroadcastAliveNotificationsTimer = null;
if (timer != null)
timer.Dispose();
}
private TimeSpan GetMinimumNonZeroCacheLifetime()
{
var nonzeroCacheLifetimesQuery = (from device
in _Devices
where device.CacheLifetime != TimeSpan.Zero
select device.CacheLifetime).ToList();
if (nonzeroCacheLifetimesQuery.Any())
return nonzeroCacheLifetimesQuery.Min();
else
return TimeSpan.Zero;
}
private string GetFirstHeaderValue(System.Net.Http.Headers.HttpRequestHeaders httpRequestHeaders, string headerName)
{
string retVal = null;
IEnumerable<String> values = null;
if (httpRequestHeaders.TryGetValues(headerName, out values) && values != null)
retVal = values.FirstOrDefault();
return retVal;
}
public Action<string> LogFunction { get; set; }
private void WriteTrace(string text)
{
if (LogFunction != null)
{
LogFunction(text);
}
//System.Diagnostics.Debug.WriteLine(text, "SSDP Publisher");
}
private void WriteTrace(string text, SsdpDevice device)
{
var rootDevice = device as SsdpRootDevice;
if (rootDevice != null)
WriteTrace(text + " " + device.DeviceType + " - " + device.Uuid + " - " + rootDevice.Location);
else
WriteTrace(text + " " + device.DeviceType + " - " + device.Uuid);
}
private void CommsServer_RequestReceived(object sender, RequestReceivedEventArgs e)
{
if (this.IsDisposed) return;
if (string.Equals(e.Message.Method.Method, SsdpConstants.MSearchMethod, StringComparison.OrdinalIgnoreCase))
{
//According to SSDP/UPnP spec, ignore message if missing these headers.
// Edit: But some devices do it anyway
//if (!e.Message.Headers.Contains("MX"))
// WriteTrace("Ignoring search request - missing MX header.");
//else if (!e.Message.Headers.Contains("MAN"))
// WriteTrace("Ignoring search request - missing MAN header.");
//else
ProcessSearchRequest(GetFirstHeaderValue(e.Message.Headers, "MX"), GetFirstHeaderValue(e.Message.Headers, "ST"), e.ReceivedFrom, e.LocalIpAddress, CancellationToken.None);
}
}
private class SearchRequest
{
public IpEndPointInfo EndPoint { get; set; }
public DateTime Received { get; set; }
public string SearchTarget { get; set; }
public string Key
{
get { return this.SearchTarget + ":" + this.EndPoint.ToString(); }
}
public bool IsOld()
{
return DateTime.UtcNow.Subtract(this.Received).TotalMilliseconds > 500;
}
}
}
}