来自不受限制的appdomain的securityexception

Question

我正在尝试将插件系统添加到我的应用程序中。我已经使用一些有限的权限集创建了沙盒appdomain。当来自沙盒appdomain的代码引发应该在具有可信代码的域中处理的事件时，问题就出现了。我创建了一个简单的应用程序来显示问题。

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

namespace SandBoxTest
{
    class Program
    {
        static void Main(string[] args)
        {
            var permissionSet = new PermissionSet(PermissionState.None);
            permissionSet.AddPermission(new SecurityPermission(SecurityPermissionFlag.AllFlags));
            permissionSet.AddPermission(new ReflectionPermission(PermissionState.Unrestricted));

            var setup = new AppDomainSetup
            {
                ApplicationBase = AppDomain.CurrentDomain.BaseDirectory
            };
            var sandBoxDomain = AppDomain.CreateDomain("Sandbox", null, setup, permissionSet);
            var remoteObject = sandBoxDomain.CreateInstanceAndUnwrap(typeof (RemoteObject).Assembly.FullName, typeof (RemoteObject).FullName) as RemoteObject;
            remoteObject.EventFromSandBox += HandlerInTrustedDomainOnEventFromSandBox;
            remoteObject.RaiseEventFromSandBox();

            Console.ReadKey();
        }

        private static void HandlerInTrustedDomainOnEventFromSandBox()
        {
            File.ReadAllText(@"C:\passwords.txt");
        }
    }

    class RemoteObject : MarshalByRefObject
    {
        public event Action EventFromSandBox;

        public void RaiseEventFromSandBox()
        {
            var handler = EventFromSandBox;
            if (handler != null) 
                handler();
        }
    }
}

在此示例异常中“请求类型'System.Security.Permissions.FileIOPermission，mscorlib，Version = 4.0.0.0，Culture = neutral，PublicKeyToken = b77a5c561934e089'失败”的权限被抛出。

如果没有安全检查，我应该怎样处理来自沙盒域的事件？