ASP.net MVC 基于角色的权限控制系统的实现

浏览数：25 / 时间：2015年06月09日

一、引言

我们都知道ASP.net mvc权限控制都是实现AuthorizeAttribute类的OnAuthorization方法。

下面是最常见的实现方式：

 public class CustomAuthorizeAttribute : AuthorizeAttribute
    {
        public override void OnAuthorization(AuthorizationContext filterContext)
        {
           if (!filterContext.RequestContext.HttpContext.Request.IsAuthenticated)
            {
                filterContext.Result = new RedirectToRouteResult(new RouteValueDictionary(new { controller = "account", action = "login", returnUrl = filterContext.HttpContext.Request.Url, returnMessage = "您无权查看." }));
                return;
            }
          base.OnAuthorization(filterContext);
        }
}

然后在需要验证的Action上打上[CustomAuthorize]标签就可以了。

这种方式是比较粗粒度的解决方案，由于是已经将定义好（约定好的）权限hard code带对应的Action上，所以无法实现用户自定义权限控制。

看一下代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;

namespace Deepleo.Role.Controllers
{
    public class UserController : Controller
    {
        [UserAuthorize]
        public ActionResult Index()
        {
            return View();
        }
       [AdminAuthorize]
        public ActionResult Admin()
        {
            return View();
        }
        [UserAuthorize]
        public ActionResult Detail()
        {
            return View();
        }
    }
}

我们有一个UserController,他有3个Action:Index,Admin,Detail.其中Admin需要系统管理员权限，其他两个值需要User权限。这样就需要建立AdminAuthorizeAttribute和UserAuthorizeAttribute.这样做就无法实现用户自定义权限。

二、基于角色的权限控制系统

基于角色的权限控制系统RBAC（Role Based Access Control）是目前最流行，也是最通用的权限控制系统。

对于ASP.NET MVC来说，这套系统很容易实现：Controller下的每一个Action可以看作是一个权限，角色就相当于多个权限的组合。

然后我们新建一个RoleAuthorizeAttribute，即对角色的属性描述。

2.1 如何鉴权

这个RoleAuthorizeAttribute的关键在于如何拿到ControllerName和ActionName，查阅msdn其实很容易就实现了，不多说，直接上代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.Mvc;
using System.Web.Routing;
using Deepleo.Role.Services;

namespace Deepleo.Role.Attributes
{
    public class RoleAuthorizeAttribute : AuthorizeAttribute
    {
        public override void OnAuthorization(AuthorizationContext filterContext)
        {
            var isAuth = false;
            if (!filterContext.RequestContext.HttpContext.Request.IsAuthenticated)
            {
                isAuth = false;
            }
            else
            {
                if (filterContext.RequestContext.HttpContext.User.Identity != null)
                {
                    var roleService = new RoleService();
                    var actionDescriptor = filterContext.ActionDescriptor;
                    var controllerDescriptor = actionDescriptor.ControllerDescriptor;
                    var controller = controllerDescriptor.ControllerName;
                    var action = actionDescriptor.ActionName;
                    var ticket = (filterContext.RequestContext.HttpContext.User.Identity as FormsIdentity).Ticket;
                    var role = roleService.GetById(ticket.Version);
                    if (role != null)
                    {
                        isAuth = role.Permissions.Any(x => x.Permission.Controller.ToLower() == controller.ToLower() && x.Permission.Action.ToLower() == action.ToLower());
                    }
                }
            }
            if (!isAuth)
            {
                filterContext.Result = new RedirectToRouteResult(new RouteValueDictionary(new { controller = "account", action = "login", returnUrl = filterContext.HttpContext.Request.Url, returnMessage = "您无权查看." }));
                return;
            }
            else
            {
                base.OnAuthorization(filterContext);
            }
        }
    }
}

注意：这里用Ticket的Version存储RoleId。你也可以用其他方式。

主要是用到了 filterContext.ActionDescriptor和filterContext.ActionDescriptor。

2.2 如何生成权限控制列表

前面的role.Permissions的集合已经是定义好的权限列表。

Permissions类的定义如下:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Deepleo.Role.Entities
{
    public class PermissionDefinition
    {
        public virtual int Id
        {
            set;
            get;
        }
        public virtual int ActionNo
        {
            set;
            get;
        }

        public virtual int ControllerNo
        {
            set;
            get;
        }
        public virtual string Name
        {
            set;
            get;
        }

        public virtual string ControllerName
        {
            set;
            get;
        }
        public virtual string Controller
        {
            set;
            get;
        }
        public virtual string Action
        {
            set;
            get;
        }
        public virtual DateTime AddDate
        {
            set;
            get;
        }
    }
}

View Code

属性Controller和Action记录的是权限,ControllerName和ActionName用于显示UI，ControllerNo和ActionNo用于显示顺序控制。

这里你可以手工将所有Action录入数据库中，然后实现RolService即可。但是显然这种方法实在是太笨了，我们其实可以用反射+Attribute机制实现自动化载入权限控制表。原理很简单，我就直接上关键代码了。

以下是反射的代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Deepleo.Role.Services;
using Deepleo.Role.Attributes;
using Deepleo.Role.Entities;

namespace Deepleo.Role.Controllers
{
    public class InstallController : Controller
    {
        public ActionResult Index()
        {
            return View();
        }

        [HttpPost]
        public ActionResult Index()
        {
            try
            {
                var roleService = new RoleService();
                #region init permission
                createPermission(new UserController());
                #endregion

                var allDefinedPermissions = roleService.GetDefinedPermissions();
                #region 超级管理员角色初始化
                var adminPermissions = new List<RolePermissionInfo>();
                foreach (var d in allDefinedPermissions)
                {
                    adminPermissions.Add(new RolePermissionInfo { AddDate = DateTime.Now, Permission = d, });
                }
                int adminRoleId = roleService.AddRole(new Entities.RoleInfo
                {
                    AddDate = DateTime.Now,
                    Description = "",
                    Name = "超级管理员",
                    Permissions = adminPermissions
                });
                #endregion
                return RedirectToAction("Admin", "User");
            }
            catch (Exception ex)
            {
                ModelState.AddModelError("", ex.Message);
                return View();
            }
        }
        private void createPermission(Controller customController)
        {
            var roleService = new RoleService();

            var controllerName = "";
            var controller = ""; var controllerNo = 0;
            var actionName = ""; var action = ""; var actionNo = 0;
            var controllerDesc = new KeyValuePair<string, int>();

            var controllerType = customController.GetType();
            controller = controllerType.Name.Replace("Controller", "");//remobe controller posfix
            controllerDesc = getdesc(controllerType);
            if (!string.IsNullOrEmpty(controllerDesc.Key))
            {
                controllerName = controllerDesc.Key;
                controllerNo = controllerDesc.Value;
                foreach (var m in controllerType.GetMethods())
                {
                    var mDesc = getPropertyDesc(m);
                    if (string.IsNullOrEmpty(mDesc.Key)) continue;
                    action = m.Name;
                    actionName = mDesc.Key;
                    actionNo = mDesc.Value;
                    roleService.CreatePermissions(actionNo, controllerNo, actionName, controllerName, controller, action);
                }
            }
        }
        private KeyValuePair<string, int> getdesc(Type type)
        {
            var descriptionAttribute = (DescriptionAttribute)(type.GetCustomAttributes(false).FirstOrDefault(x => x is DescriptionAttribute));
            if (descriptionAttribute == null) return new KeyValuePair<string, int>();
            return new KeyValuePair<string, int>(descriptionAttribute.Name, descriptionAttribute.No);
        }
        private KeyValuePair<string, int> getPropertyDesc(System.Reflection.MethodInfo type)
        {
            var descriptionAttribute = (DescriptionAttribute)(type.GetCustomAttributes(false).FirstOrDefault(x => x is DescriptionAttribute));
            if (descriptionAttribute == null) return new KeyValuePair<string, int>();
            return new KeyValuePair<string, int>(descriptionAttribute.Name, descriptionAttribute.No);
        }
    }
}

View Code

以下是DescriptionAttribute的代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

namespace Deepleo.Role.Attributes
{
    public class DescriptionAttribute : Attribute
    {
        public string Name
        {
            set;
            get;
        }
        public int No
        {
            set;
            get;
        }
    }
}

View Code

然后在UserController打上DescriptionAttribute标签就可以了，如下所示：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Deepleo.Role.Attributes;

namespace Deepleo.Role.Controllers
{
    [Description(No = 1, Name = "用户")]
    public class UserController : Controller
    {
        [RoleAuthorize]
        [Description(No = 1, Name = "用户首页")]
        public ActionResult Index()
        {
            return View();
        }
        [RoleAuthorize]
        [Description(No = 1, Name = "用户管理")]
        public ActionResult Admin()
        {
            return View();
        }
        [RoleAuthorize]
        [Description(No = 1, Name = "用户详情")]
        public ActionResult Detail()
        {
            return View();
        }
    }
}