SmtpPermission.cs :  » 2.6.4-mono-.net-core » System.Net » System » Net » Mail » C# / CSharp Open Source

//
// System.Net.Mail.SmtpPermission
//
// Authors:
//  Sebastien Pouliot  <sebastien@ximian.com>
//
// Copyright (C) 2006 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

#if NET_2_0

using System.Security;
using System.Security.Permissions;

namespace System.Net.Mail{

  [Serializable]
  public sealed class SmtpPermission : CodeAccessPermission, IUnrestrictedPermission {

    private const int version = 1;

    private bool unrestricted;
    private SmtpAccess access;


    public SmtpPermission (bool unrestricted)
      : base ()
    {
      this.unrestricted = unrestricted;
      access = unrestricted ? SmtpAccess.ConnectToUnrestrictedPort : SmtpAccess.None;
    }

    public SmtpPermission (PermissionState state)
      : base ()
    {
      unrestricted = (state == PermissionState.Unrestricted);
      access =  unrestricted ? SmtpAccess.ConnectToUnrestrictedPort : SmtpAccess.None;
    }

    public SmtpPermission (SmtpAccess access)
      : base ()
    {
      // this ctor can accept invalid enum values
      this.access = access;
    }
    

    public SmtpAccess Access {
      get { return access; }
    }


    public void AddPermission (SmtpAccess access)
    {
      if (!unrestricted && (access > this.access)) {
        this.access = access;
      }
    }

    public override IPermission Copy ()
    {
      if (unrestricted) {
        return new SmtpPermission (true);
      } else {
        return new SmtpPermission (access);
      }
    }

    public override IPermission Intersect (IPermission target)
    {
      SmtpPermission sp = Cast (target);
      if (sp == null)
        return null;

      if (unrestricted && sp.unrestricted)
        return new SmtpPermission (true);
      else if (access > sp.access)
        return new SmtpPermission (sp.access);
      else
        return new SmtpPermission (access);
    }
    
    public override bool IsSubsetOf (IPermission target) 
    {
      SmtpPermission sp = Cast (target);
      if (sp == null)
        return IsEmpty ();

      if (unrestricted) {
        return sp.unrestricted;
      } else {
        return (access <= sp.access);
      }
    }

    public bool IsUnrestricted () 
    {
      return unrestricted;
    }

    public override SecurityElement ToXml ()
    {
      SecurityElement se = PermissionHelper.Element (typeof (SmtpPermission), version);
      if (unrestricted) {
        se.AddAttribute ("Unrestricted", "true");
      } else {
        switch (access) {
        case SmtpAccess.ConnectToUnrestrictedPort:
          se.AddAttribute ("Access", "ConnectToUnrestrictedPort");
          break;
        case SmtpAccess.Connect:
          se.AddAttribute ("Access", "Connect");
          break;
        // note: SmtpAccess.None and invalid values aren't serialized to XML
        }
      }
      return se;
    }
    
    public override void FromXml (SecurityElement securityElement)
    {
      PermissionHelper.CheckSecurityElement (securityElement, "securityElement", version, version);
    
      // LAMESPEC: it says to throw an ArgumentNullException in this case        
      if (securityElement.Tag != "IPermission")
        throw new ArgumentException ("securityElement");
        
      if (PermissionHelper.IsUnrestricted (securityElement))
        access = SmtpAccess.Connect;
      else
        access = SmtpAccess.None;
    }    
    
    public override IPermission Union (IPermission target) 
    {
      SmtpPermission sp = Cast (target);
      if (sp == null)
        return Copy ();

      if (unrestricted || sp.unrestricted)
        return new SmtpPermission (true);
      else if (access > sp.access)
        return new SmtpPermission (access);
      else
        return new SmtpPermission (sp.access);
    }

    // Internal helpers methods

    private bool IsEmpty ()
    {
      return (!unrestricted && (access == SmtpAccess.None));
    }

    private SmtpPermission Cast (IPermission target)
    {
      if (target == null)
        return null;

      SmtpPermission sp = (target as SmtpPermission);
      if (sp == null) {
        PermissionHelper.ThrowInvalidPermission (target, typeof (SmtpPermission));
      }

      return sp;
    }
  }
}

#endif