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ServiceSecurityContext Class

Definition

Represents the security context of a remote party. On the client, represents the service identity and, on the service, represents the client identity.

public ref class ServiceSecurityContext
public class ServiceSecurityContext
type ServiceSecurityContext = class
Public Class ServiceSecurityContext
Inheritance
ServiceSecurityContext

Examples

The following example uses the ServiceSecurityContext class to provide information about the current security context. The code creates an instance of the StreamWriter class to write the information to a file.

// When this method runs, the caller must be an authenticated user
// and the ServiceSecurityContext is not a null instance.
public double Add(double n1, double n2)
{
    // Write data from the ServiceSecurityContext to a file using the StreamWriter class.
    using (StreamWriter sw = new StreamWriter(@"c:\ServiceSecurityContextInfo.txt"))
    {
        // Write the primary identity and Windows identity. The primary identity is derived from
        // the credentials used to authenticate the user. The Windows identity may be a null string.
        sw.WriteLine("PrimaryIdentity: {0}", ServiceSecurityContext.Current.PrimaryIdentity.Name);
        sw.WriteLine("WindowsIdentity: {0}", ServiceSecurityContext.Current.WindowsIdentity.Name);

        // Write the claimsets in the authorization context. By default, there is only one claimset
        // provided by the system.
        foreach (ClaimSet claimset in ServiceSecurityContext.Current.AuthorizationContext.ClaimSets)
        {
            foreach (Claim claim in claimset)
            {
                // Write out each claim type, claim value, and the right. There are two
                // possible values for the right: "identity" and "possessproperty".
                sw.WriteLine("Claim Type: {0}, Resource: {1} Right: {2}",
                    claim.ClaimType,
                    claim.Resource.ToString(),
                    claim.Right);
                sw.WriteLine();
            }
        }
    }
    return n1 + n2;
}
' When this method runs, the caller must be an authenticated user and the ServiceSecurityContext 
' is not a null instance. 
Public Function Add(ByVal n1 As Double, ByVal n2 As Double) As Double Implements ICalculator.Add
    ' Write data from the ServiceSecurityContext to a file using the StreamWriter class.
    Dim sw As New StreamWriter("c:\ServiceSecurityContextInfo.txt")
    Try
        ' Write the primary identity and Windows identity. The primary identity is derived from 
        ' the credentials used to authenticate the user. The Windows identity may be a null string.
        sw.WriteLine("PrimaryIdentity: {0}", ServiceSecurityContext.Current.PrimaryIdentity.Name)
        sw.WriteLine("WindowsIdentity: {0}", ServiceSecurityContext.Current.WindowsIdentity.Name)

        ' Write the claimsets in the authorization context. By default, there is only one claimset
        ' provided by the system. 
        Dim claimset As ClaimSet
        For Each claimset In ServiceSecurityContext.Current.AuthorizationContext.ClaimSets
            Dim claim As Claim
            For Each claim In claimset
                ' Write out each claim type, claim value, and the right. There are two
                ' possible values for the right: "identity" and "possessproperty". 
                sw.WriteLine("Claim Type: {0}, Resource: {1} Right: {2}", _
                claim.ClaimType, _
                claim.Resource.ToString(), _
                claim.Right)
                sw.WriteLine()
            Next claim
        Next claimset
    Finally
        sw.Dispose()
    End Try
    Return n1 + n2
End Function

The following example shows an implementation of the CheckAccessCore method that uses the ServiceSecurityContext to parse a set of claims.

public class MyServiceAuthorizationManager : ServiceAuthorizationManager
{
    protected override bool CheckAccessCore(OperationContext operationContext)
    {
        // Extract the action URI from the OperationContext. Match this against the claims
        // in the AuthorizationContext.
        string action = operationContext.RequestContext.RequestMessage.Headers.Action;
        Console.WriteLine("action: {0}", action);

        // Iterate through the various claimsets in the AuthorizationContext.
        foreach(ClaimSet cs in operationContext.ServiceSecurityContext.AuthorizationContext.ClaimSets)
        {
            // Examine only those claim sets issued by System.
            if (cs.Issuer == ClaimSet.System)
            {
                // Iterate through claims of type "http://example.org/claims/allowedoperation".
                foreach (Claim c in cs.FindClaims("http://example.org/claims/allowedoperation",
                    Rights.PossessProperty))
                {
                    // Write the Claim resource to the console.
                    Console.WriteLine("resource: {0}", c.Resource.ToString());

                    // If the Claim resource matches the action URI then return true to allow access.
                    if (action == c.Resource.ToString())
                        return true;
                }
            }
        }

        // If this point is reached, return false to deny access.
         return false;
    }
}
Public Class MyServiceAuthorizationManager
    Inherits ServiceAuthorizationManager
    
    Protected Overrides Function CheckAccessCore(ByVal operationContext As OperationContext) As Boolean 
        ' Extract the action URI from the OperationContext. Match this against the claims
        ' in the AuthorizationContext.
        Dim action As String = operationContext.RequestContext.RequestMessage.Headers.Action
        Console.WriteLine("action: {0}", action)
        
        ' Iterate through the various claimsets in the authorizationcontext.
        Dim cs As ClaimSet
        For Each cs In  operationContext.ServiceSecurityContext.AuthorizationContext.ClaimSets
            ' Examine only those claim sets issued by System.
            If cs.Issuer Is ClaimSet.System Then
                ' Iterate through claims of type "http://example.org/claims/allowedoperation".
                Dim c As Claim
                For Each c In  cs.FindClaims("http://example.org/claims/allowedoperation", _
                        Rights.PossessProperty)
                    ' Write the Claim resource to the console.
                    Console.WriteLine("resource: {0}", c.Resource.ToString())
                    
                    ' If the Claim resource matches the action URI then return true to allow access.
                    If action = c.Resource.ToString() Then
                        Return True
                    End If
                Next c
            End If
        Next cs 
        ' If we get here, return false, denying access.
        Return False
    
    End Function 
End Class

Remarks

The data is part of the SecurityMessageProperty for a message.

Use this class to obtain information about a remote security context at runtime. A security context is created when a client is successfully authenticated and authorized to access a method. When a message is successfully authenticated and authorized, the security information from the client and for the current service instance can be obtained from an instance of this class.

You can retrieve an instance of the ServiceSecurityContext from the Current property of the OperationContext class, or use it from within a service operation method, as shown in the following example.

Parsing a ClaimSet

A common use of the class is to retrieve the current set of claims for the purpose of identifying or authorizing a client when accessing a method. The ClaimSet class contains a collection of Claim objects, and each can be parsed to determine whether a specific claim is present. If the specified claim is provided, authorization can be granted. This functionality is provided by overriding the CheckAccessCore method of the ServiceAuthorizationManager class. For a complete example, see the Authorization Policy.

Note that under some circumstances, the IsAuthenticated property of the IIdentity interface returns true even if the remote client is authenticated as an anonymous user. (The PrimaryIdentity property returns an implementation of the IIdentity interface.) The following circumstances must be true for this to occur:

  • The service uses Windows authentication.

  • The service allows anonymous logons.

  • The binding is a <customBinding>.

  • The custom binding includes a <security> element.

  • The <security> element includes a <secureConversationBootstrap> with the requireSecurityContextCancellation attribute set to false.

Constructors

ServiceSecurityContext(AuthorizationContext, ReadOnlyCollection<IAuthorizationPolicy>)

Initializes a new instance of the ServiceSecurityContext class with the specified authorization parameters and collection of policies.

ServiceSecurityContext(AuthorizationContext)

Initializes a new instance of the ServiceSecurityContext class with the specified authorization parameters.

ServiceSecurityContext(ReadOnlyCollection<IAuthorizationPolicy>)

Initializes a new instance of the ServiceSecurityContext class with the collection of policies object.

Properties

Anonymous

Returns an instance of the ServiceSecurityContext class that contains an empty collection of claims, identities, and other context data that is usually used to represent an anonymous party.

AuthorizationContext

Gets the authorization information for an instance of this class. The AuthorizationContext contains a collection of ClaimSet that the application can interrogate and retrieve the information of the party.

AuthorizationPolicies

Gets the collection of policies associated with an instance of this class.

Current

Gets the current ServiceSecurityContext.

IsAnonymous

Gets a value that indicates whether the current client has provided credentials to the service.

PrimaryIdentity

Gets the primary identity associated with the current setting.

WindowsIdentity

Gets the Windows identity of the current setting.

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Applies to

See also