IAuthorizationPolicy Interfaccia

Definizione

Spazio dei nomi:

System.IdentityModel.Policy

Assembly:

System.ServiceModel.Primitives.dll

Pacchetto:

System.ServiceModel.Primitives v6.2.0

Origine:

IAuthorizationPolicy.cs

Definisce un set di regole per l'autorizzazione di un utente in base a un set di attestazioni.

public interface class IAuthorizationPolicy : System::IdentityModel::Policy::IAuthorizationComponent

public interface IAuthorizationPolicy : System.IdentityModel.Policy.IAuthorizationComponent

type IAuthorizationPolicy = interface
    interface IAuthorizationComponent

Public Interface IAuthorizationPolicy
Implements IAuthorizationComponent

Implementazioni

IAuthorizationComponent

Esempio

public class MyAuthorizationPolicy : IAuthorizationPolicy
{
    string id;

    public MyAuthorizationPolicy()
    {
        id =  Guid.NewGuid().ToString();
    }

    public bool Evaluate(EvaluationContext evaluationContext, ref object state)
    {
        bool bRet = false;
        CustomAuthState customstate = null;

        // If state is null, then this method has not been called before, so
        // set up a custom state.
        if (state == null)
        {
            customstate = new CustomAuthState();
            state = customstate;
        }
        else
        {
            customstate = (CustomAuthState)state;
        }

        Console.WriteLine("Inside MyAuthorizationPolicy::Evaluate");

        // If claims have not been added yet...
        if (!customstate.ClaimsAdded)
        {
            // Create an empty list of Claims.
            IList<Claim> claims = new List<Claim>();

            // Iterate through each of the claim sets in the evaluation context.
            foreach (ClaimSet cs in evaluationContext.ClaimSets)
                // Look for Name claims in the current claim set.
                foreach (Claim c in cs.FindClaims(ClaimTypes.Name, Rights.PossessProperty))
                    // Get the list of operations the given username is allowed to call.
                    foreach (string s in GetAllowedOpList(c.Resource.ToString()))
                    {
                        // Add claims to the list.
                        claims.Add(new Claim("http://example.org/claims/allowedoperation", s, Rights.PossessProperty));
                        Console.WriteLine("Claim added {0}", s);
                    }

            // Add claims to the evaluation context.
            evaluationContext.AddClaimSet(this, new DefaultClaimSet(this.Issuer,claims));

            // Record that claims have been added.
            customstate.ClaimsAdded = true;

            // Return true, which indicates this need not be called again.
            bRet = true;
        }
        else
        {
            // This point should not be reached, but just in case...
            bRet = true;
        }

        return bRet;
    }
    public ClaimSet Issuer
    {
        get { return ClaimSet.System; }
    }

    public string Id
    {
        get { return id; }
    }

    // This method returns a collection of action strings that indicate the
    // operations that the specified username is allowed to call.
    private IEnumerable<string> GetAllowedOpList(string username)
    {
        IList<string> ret = new List<string>();

        if (username == "test1")
        {
            ret.Add ( "http://Microsoft.ServiceModel.Samples/ICalculator/Add");
            ret.Add ("http://Microsoft.ServiceModel.Samples/ICalculator/Multiply");
            ret.Add("http://Microsoft.ServiceModel.Samples/ICalculator/Subtract");
        }
        else if (username == "test2")
        {
            ret.Add ( "http://Microsoft.ServiceModel.Samples/ICalculator/Add");
            ret.Add ("http://Microsoft.ServiceModel.Samples/ICalculator/Subtract");
        }
        return ret;
    }

    // internal class for state
    class CustomAuthState
    {
        bool bClaimsAdded;

        public CustomAuthState()
        {
            bClaimsAdded = false;
        }

        public bool ClaimsAdded { get { return bClaimsAdded; }
                                  set {  bClaimsAdded = value; } }
    }
}

Public Class MyAuthorizationPolicy
    Implements IAuthorizationPolicy
    Private value_id As String


    Public Sub New()
        value_id = Guid.NewGuid().ToString()

    End Sub 

    Public Function Evaluate(ByVal evaluationContext As EvaluationContext, _
         ByRef state As Object) As Boolean Implements IAuthorizationPolicy.Evaluate

        Dim bRet As Boolean = False
        Dim customstate As CustomAuthState = Nothing

        ' If state is null, then this method has not been called before, so 
        ' set up a custom state.
        If state Is Nothing Then
            customstate = New CustomAuthState()
            state = customstate
        Else
            customstate = CType(state, CustomAuthState)
        End If
        Console.WriteLine("Inside MyAuthorizationPolicy::Evaluate")

        ' If the claims have not been added yet...
        If Not customstate.ClaimsAdded Then
            ' Create an empty list of Claims
            Dim claims As New List(Of Claim)

            ' Iterate through each of the claimsets in the evaluation context.
            Dim cs As ClaimSet
            For Each cs In evaluationContext.ClaimSets
                ' Look for Name claims in the current claim set.
                Dim c As Claim
                For Each c In cs.FindClaims(ClaimTypes.Name, Rights.PossessProperty)
                    ' Get the list of operations the given username is allowed to call.
                    Dim s As String
                    For Each s In GetAllowedOpList(c.Resource.ToString())

                        ' Add claims to the list
                        claims.Add(New Claim("http://example.org/claims/allowedoperation", _
                                    s, Rights.PossessProperty))
                        Console.WriteLine("Claim added {0}", s)
                    Next s
                Next c
            Next cs 
            
            ' Add claims to the evaluation context.
            evaluationContext.AddClaimSet(Me, New DefaultClaimSet(Me.Issuer, claims))

            ' Record that claims have been added.
            customstate.ClaimsAdded = True

            ' Return true, which indicates the method need not to be called again.
            bRet = True
        Else
            ' Should never get here, but just in case...
            bRet = True
        End If


        Return bRet

    End Function 'Evaluate

    Public ReadOnly Property Issuer() As ClaimSet Implements IAuthorizationPolicy.Issuer

        Get
            Return ClaimSet.System
        End Get
    End Property

    Public ReadOnly Property Id() As String Implements IAuthorizationPolicy.Id

        Get
            Return value_id
        End Get
    End Property
    ' This method returns a collection of action strings that indicate the 
    ' operations that the specified username is allowed to call.
    Private Shared Function GetAllowedOpList(ByVal username As String) As IEnumerable(Of String)


        Dim ret As New List(Of String)

        If username = "test1" Then
            ret.Add("http://Microsoft.ServiceModel.Samples/ICalculator/Add")
            ret.Add("http://Microsoft.ServiceModel.Samples/ICalculator/Multiply")
            ret.Add("http://Microsoft.ServiceModel.Samples/ICalculator/Subtract")
        ElseIf username = "test2" Then
            ret.Add("http://Microsoft.ServiceModel.Samples/ICalculator/Add")
            ret.Add("http://Microsoft.ServiceModel.Samples/ICalculator/Subtract")
        End If
        Return ret

    End Function 

    ' This is an internal class for state.
    Class CustomAuthState
        Private bClaimsAdded As Boolean


        Public Sub New()

        End Sub 


        Public Property ClaimsAdded() As Boolean
            Get
                Return bClaimsAdded
            End Get
            Set(ByVal value As Boolean)
                bClaimsAdded = value
            End Set
        End Property
    End Class 
End Class

Commenti

Implementare l'interfaccia IAuthorizationPolicy per aggiungere o mappare un set di attestazioni a un altro set. Dei criteri di autorizzazione esaminano un set di attestazioni e aggiungono attestazioni aggiuntive in base al set corrente. Ad esempio, dei criteri di autorizzazione possono valutare un'attestazione che contiene la data di nascita e aggiungere un'attestazione che affermi che l'utente ha più di 21 anni e aggiungere quindi un'attestazione Over21 alla classe EvaluationContext.

Le classi che implementano l'interfaccia IAuthorizationPolicy non autorizzano gli utenti, ma consentono alla classe ServiceAuthorizationManager di concedere tale autorizzazione. La classe ServiceAuthorizationManager chiama il metodo Evaluate per tutti i criteri di autorizzazione attivi. Il metodo Evaluate determina se per l'utente devono essere aggiunte ulteriori attestazioni, in base al contesto corrente. Il metodo Evaluate dei criteri di autorizzazione può essere chiamato ogni volta che vengono aggiunte attestazioni alla classe EvaluationContext da altri criteri di autorizzazione. Una volta terminati tutti i criteri di autorizzazione attivi, la classe ServiceAuthorizationManager prende decisioni di autorizzazione in base al set di attestazioni finale. La classe ServiceAuthorizationManager crea quindi una classe AuthorizationContext che contiene un set di attestazioni non modificabile che riflette queste decisioni di autorizzazione.

Proprietà

Id	Ottiene una stringa che identifica il componente di autorizzazione corrente. (Ereditato da IAuthorizationComponent)
Issuer	Ottiene un set di attestazioni che rappresenta l'emittente dei criteri di autorizzazione.

Metodi

Evaluate(EvaluationContext, Object)

Valuta se un utente soddisfa i requisiti per i criteri di autorizzazione correnti.

Vedi anche

• Esempio di criteri di autorizzazione