Export (0) Print
Expand All
This topic has not yet been rated - Rate this topic

SocketPermission Class

Controls rights to make or accept connections on a transport address.

Namespace:  System.Net
Assembly:  System (in System.dll)
[SerializableAttribute]
public sealed class SocketPermission : CodeAccessPermission, 
	IUnrestrictedPermission

The SocketPermission type exposes the following members.

  NameDescription
Public methodSocketPermission(PermissionState)Initializes a new instance of the SocketPermission class that allows unrestricted access to the Socket or disallows access to the Socket.
Public methodSocketPermission(NetworkAccess, TransportType, String, Int32)Initializes a new instance of the SocketPermission class for the given transport address with the specified permission.
Top
  NameDescription
Public propertyAcceptListGets a list of EndpointPermission instances that identifies the endpoints that can be accepted under this permission instance.
Public propertyConnectListGets a list of EndpointPermission instances that identifies the endpoints that can be connected to under this permission instance.
Top
  NameDescription
Public methodAddPermissionAdds a permission to the set of permissions for a transport address.
Public methodAssertDeclares that the calling code can access the resource protected by a permission demand through the code that calls this method, even if callers higher in the stack have not been granted permission to access the resource. Using Assert can create security issues. (Inherited from CodeAccessPermission.)
Public methodCopyCreates a copy of a SocketPermission instance. (Overrides CodeAccessPermission.Copy().)
Public methodDemandForces a SecurityException at run time if all callers higher in the call stack have not been granted the permission specified by the current instance. (Inherited from CodeAccessPermission.)
Public methodDeny Obsolete. Prevents callers higher in the call stack from using the code that calls this method to access the resource specified by the current instance. (Inherited from CodeAccessPermission.)
Public methodEqualsDetermines whether the specified CodeAccessPermission object is equal to the current CodeAccessPermission. (Inherited from CodeAccessPermission.)
Public methodFromXmlReconstructs a SocketPermission instance for an XML encoding. (Overrides CodeAccessPermission.FromXml(SecurityElement).)
Public methodGetHashCodeGets a hash code for the CodeAccessPermission object that is suitable for use in hashing algorithms and data structures such as a hash table. (Inherited from CodeAccessPermission.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodIntersectReturns the logical intersection between two SocketPermission instances. (Overrides CodeAccessPermission.Intersect(IPermission).)
Public methodIsSubsetOfDetermines if the current permission is a subset of the specified permission. (Overrides CodeAccessPermission.IsSubsetOf(IPermission).)
Public methodIsUnrestrictedChecks the overall permission state of the object.
Public methodPermitOnlyPrevents callers higher in the call stack from using the code that calls this method to access all resources except for the resource specified by the current instance. (Inherited from CodeAccessPermission.)
Public methodToStringCreates and returns a string representation of the current permission object. (Inherited from CodeAccessPermission.)
Public methodToXmlCreates an XML encoding of a SocketPermission instance and its current state. (Overrides CodeAccessPermission.ToXml().)
Public methodUnionReturns the logical union between two SocketPermission instances. (Overrides CodeAccessPermission.Union(IPermission).)
Top
  NameDescription
Public fieldStatic memberAllPortsDefines a constant that represents all ports.
Top

SocketPermission instances control permission to accept connections or initiate Socket connections. A Socket permission can be established for a host name or IP address, a port number, and a transport protocol.

NoteNote

Avoid creating socket permissions using host names, as these names have to be resolved to IP addresses, and this might block the stack.

The following example demonstrates how to use the SocketPermission class to set, change, and enforce various socket access restrictions.


     // Creates a SocketPermission restricting access to and from all URIs.
     SocketPermission mySocketPermission1 = new SocketPermission(PermissionState.None);

     // The socket to which this permission will apply will allow connections from www.contoso.com.
     mySocketPermission1.AddPermission(NetworkAccess.Accept, TransportType.Tcp, "www.contoso.com", 11000);

     // Creates a SocketPermission which will allow the target Socket to connect with www.southridgevideo.com.
     SocketPermission mySocketPermission2 =
                                new SocketPermission(NetworkAccess.Connect, TransportType.Tcp, "www.southridgevideo.com", 11002);

     // Creates a SocketPermission from the union of two SocketPermissions.
     SocketPermission mySocketPermissionUnion = 
                                (SocketPermission)mySocketPermission1.Union(mySocketPermission2);

     // Checks to see if the union was successfully created by using the IsSubsetOf method. 
     if (mySocketPermission1.IsSubsetOf(mySocketPermissionUnion) && 
     	   mySocketPermission2.IsSubsetOf(mySocketPermissionUnion)){
          Console.WriteLine("This union contains permissions from both mySocketPermission1 and mySocketPermission2"); 

          // Prints the allowable accept URIs to the console.
          Console.WriteLine("This union accepts connections on :");

          IEnumerator myEnumerator = mySocketPermissionUnion.AcceptList;
	   while (myEnumerator.MoveNext()) {
               Console.WriteLine(((EndpointPermission)myEnumerator.Current).ToString());
	        }      

             // Prints the allowable connect URIs to the console.
          Console.WriteLine("This union permits connections to :");

          myEnumerator = mySocketPermissionUnion.ConnectList;
	   while (myEnumerator.MoveNext()) {
               Console.WriteLine(((EndpointPermission)myEnumerator.Current).ToString());
	        }      

           }


     // Creates a SocketPermission from the intersect of two SocketPermissions.
     SocketPermission mySocketPermissionIntersect = 
                               (SocketPermission)mySocketPermission1.Intersect(mySocketPermissionUnion);

     // mySocketPermissionIntersect should now contain the permissions of mySocketPermission1. 
     if (mySocketPermission1.IsSubsetOf(mySocketPermissionIntersect)){
          Console.WriteLine("This is expected");
     }
    // mySocketPermissionIntersect should not contain the permissios of mySocketPermission2. 
     if (mySocketPermission2.IsSubsetOf(mySocketPermissionIntersect)){
          Console.WriteLine("This should not print");
     }



// Creates a copy of the intersect SocketPermission.
     SocketPermission mySocketPermissionIntersectCopy = 
                               (SocketPermission)mySocketPermissionIntersect.Copy();

     if (mySocketPermissionIntersectCopy.Equals(mySocketPermissionIntersect)){
     Console.WriteLine("Copy successfull");
     }


     // Converts a SocketPermission to XML format and then immediately converts it back to a SocketPermission.
     mySocketPermission1.FromXml(mySocketPermission1.ToXml());


     // Checks to see if permission for this socket resource is unrestricted.  If it is, then there is no need to 
     // demand that permissions be enforced. 
     if (mySocketPermissionUnion.IsUnrestricted()){
     	
          //Do nothing.  There are no restrictions.

     }
     else{
         // Enforces the permissions found in mySocketPermissionUnion on any Socket Resources used below this statement. 
         mySocketPermissionUnion.Demand();
     }

	IPHostEntry myIpHostEntry = Dns.Resolve("www.contoso.com");
	IPEndPoint myLocalEndPoint = new IPEndPoint(myIpHostEntry.AddressList[0], 11000);

       Socket s = new Socket(myLocalEndPoint.Address.AddressFamily,
       	                           SocketType.Stream,
                                         ProtocolType.Tcp);
       try{
            s.Connect(myLocalEndPoint);
       }
       catch (Exception e){
            Console.WriteLine("Exception Thrown: " + e.ToString());
       } 

      // Perform all socket operations in here.

      s.Close();

.NET Framework

Supported in: 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Show:
© 2014 Microsoft. All rights reserved.