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Issue with WebMethod being Static in C# ASP.NET Codebehind

Due to a problem caused by having multiple forms on a single page, I used an AJAX call to a WebMethod to submit my form instead of using ASP controls. However, in doing this, the previous method I had used to create a new entry into my database no longer works because a WebMethod must be static.
I have authenticated my user already using ASPX authentication, and am trying to retrieve the username and ID of that user with codebehind. The user has already been authenticated on Page_Load, but it seems I cannot access this information through my WebMethod. Is this possible to do inside of a static WebMethod? Thank you for all of your help in advance!
[WebMethod]
public static void CreateJob()
{
Submit_Job();
}
public static void Submit_Job()
{
if (Page.User.Identity.IsAuthenticated)
{
try
{
string username = Context.User.Identity.Name;
}
catch
{
Context.GetOwinContext().Authentication.SignOut();
}
}
var manager = new UserManager();
var usernameDatabase = new ApplicationUser() { UserName = username };
usernameDatabase = manager.Find(username, "password here");
if (usernameDatabase != null)
{
IdentityHelper.SignIn(manager, usernameDatabase, isPersistent: false);
string jobTitle = Request.Form["jobTitle"];
using (var ctx = new CreateUserContext(ConfigurationManager.ConnectionStrings["myconnectionstring"].ConnectionString))
{
Job job = new Job()
{
job_title = jobTitle
};
ctx.Jobs.Add(job);
ctx.SaveChanges();
}
}
}
Edit:
There are errors for example with Page.User.Identity.IsAuthenticated -- Page, Context, and Request all appear that they cannot be static.
The specific error:
(An object reference is required for the non-static field, method, or property 'Control.Page') as well as with Context and Request.

Moving it from a simple comment
I had the same issue recently.
Luckily, whenever a user signs in our application, we store the user information encrypted into a session variable, so I retrieve that information, pass it to our user's class constructor, which decrypts it and I can use my logged in users info without a hassle.
So, my solution is to store the users info in the Session, but be careful what you store. Maybe serialize the users object and store in the session, then, whenever you need it
public void Page_Load()
{
// Retrieve authenticated user information
UserClass userObject = GetUserCredentials();
// Call a method that turns the authenticated user object into a string that contains the users session information. Given the sensivity of this information, might want to try to encrypt it or offuscate it. Store it in a session variable as a string
Session["UserContext"] = userObject.SerializeUser()
/* rest of the page code goes here */
}
[WebMethod(EnableSession=true)]
public static void CreateJob()
{
Submit_Job();
}
public static void Submit_Job()
{
// Lets get the authenticated user information through the session variable. Due to the static nature of the method, we can't access the Session variables directly, so we call it using the current HttpContext
string serializedUserInfo = )HttpContext.Current.Session["UserContext"].ToString();
// Let's create the users object. In my case, we have a overcharged constructor that receives the users serialized/encrypted information, descrypts it, deserializes it, and return a instance of the class with the deserialized information
UserClass userObject = new UserClass(serializedUserInfo);
// Do whatever the method has to do now!
}
On the subject of serialization, a quick google search with "c# object serialization" will bring you several good matches. XML and JSON are 2 of the most used kind of serialization, specially on web methods. Binary serialization is a good option to also obfuscate information of the logged in user

ASP.NET Security: single entry of role names

We're building an ASP.NET app, and have a requirement to use the corporate LDAP system (Siteminder) for authentication (upside: no login dialogs). Roles are created in the LDAP tool, and users are assigned to the roles by userland managers (read: the structure has to be easily understood). Currently, all apps that use the system use a dual-entry process whereby the roles identified in the app are hand-entered into the LDAP system and users are assigned, then app functions are assigned to their role mirrors in an app-based control panel. This works, but it bothers me that dual-entry is required.
What I would like to achieve is something where the app queries the LDAP system to get a list of roles that are assigned to the app (which is identified in the LDAP system) and populate the role:function control panel with them. This part seems really straightforward. However, I lose clarity when it comes to figuring out what to put in the Authorize attribute:
[Authorize(Roles = "Admin, Moderator")]
would become... what?
[Authorize(LoadedRoles(r => r.FindAll("some expression that describes the roles that have a particular permission")))]
I'm seriously into blue sky territory here. I read this question, and liked - from an architectural standpoint - the answer that suggested making the permissions the roles. But that might not be acceptable to the userland managers that needed to manage users. On the other hand, this question turns things into non-string resources, but I can't conceive of how to translate that into "roles that have this sort of function included".
Any suggestions?
Update:
Based on the advice of #venerik below, I've made some progress. For the time being, I'm encapsulating everything in the [AuthorizeFunctionAttribute], and will farm the individual pieces out where they belong later. To that end, I created three variables:
private IList<KeyValuePair<long, string>> Roles;
private IList<KeyValuePair<long, string>> Functions;
private IList<RoleFunction> RoleFunctions;
...then put static data in them:
Roles = new ICollection<KeyValuePair<long, string>>();
Roles.Add(KeyValuePair<long, string>(1, "Basic User"));
Roles.Add(KeyValuePair<long, string>(2, "Administrator"));
Functions = new ICollection<KeyValuePair<long, string>>();
Functions.Add(KeyValuePair<long,string>(1,"List Things"));
Functions.Add(KeyValuePair<long,string>(2,"Add Or Edit Things"));
Functions.Add(KeyValuePair<long,string>(3,"Delete Things"));
...and finally bound them together (in a complicated manner that lays the groundwork for the future):
RoleFunctions = new IList<RoleFunction>();
RoleFunctions.Add(
new RoleFunction
{
RoleId = Roles.Where( r => r.Value == "Basic User").FirstOrDefault().Key,
FunctionId = Functions.Where( f => f.Value == "List Things" ).FirstOrDefault().Key,
isAuthorized = true
},
new RoleFunction
{
RoleId = Roles.Where( r => r.Value == "Administrator").FirstOrDefault().Key,
FunctionId = Functions.Where( f => f.Value == "Add or Edit Things" ).FirstOrDefault().Key,
isAuthorized = true
},
// More binding...
);
I feel good about this so far. So I went researching AuthorizeCore to see what I needed to do there. However, per the comment at the bottom of the page, it's not very helpful. I more or less get that at the end, the method needs to return a bool value. And I get that I need to check that one of the User.Roles array fits the permission that's passed in through [AuthorizeFunction("List Things")].
Update (again):
I've got the following code, which seems like it will do what I need (one method needs fleshing out):
/// <summary>An authorization attribute that takes "function name" as a parameter
/// and checks to see if the logged-in user is authorized to use that function.
/// </summary>
public class AuthorizeFunctionAttribute : AuthorizeAttribute
{
private IList<KeyValuePair<long, string>> Roles;
private IList<KeyValuePair<long, string>> Functions;
private IList<RoleFunction> RoleFunctions;
public string Function { get; private set; }
public AuthorizeFunctionAttribute(string FunctionName)
{
Function = FunctionName;
Roles = SetApplicationRoles();
Functions = SetApplicationFunctions();
RoleFunctions = SetRoleFunctions();
}
protected virtual bool AuthorizeCore(HttpContextBase httpContext)
{
bool userIsAuthorized = false;
foreach (string ur in GetUserRoles(httpContext.Current.Request.Headers["SM_USER"]))
{
long roleId = Roles.Where( sr => sr.Value == ur )
.First().Key;
long functionId = Functions.Where( sf => sf.Value == Function )
.First().Key;
// If any role is authorized for this function, set userIsAuthorized to true.
// DO NOT set userIsAuthorized to false within this loop.
if (RoleFunctions.Where(rf => rf.RoleId == roleId && rf.FunctionId == functionId)
.First().isAuthorized)
{
userIsAuthorized = true;
}
}
return userIsAuthorized;
}
Previously I didn't know enough about the underlying bits of creating a custom attribute to get out of my own way. However, this MSDN article told me what should have been obvious to me in the beginning: build it yourself. So, once I get the GetUserRoles() method put together, I should be underway.

I think you can solve this using a custom AuthorizeAttribute. In a project I worked close to they used that to access Active Directory (as described in this answer).
In your case it would look something like:
public class AuthorizeWithLDAPAttribute(string functionName) : AuthorizeAttribute
{
protected virtual bool AuthorizeCore(HttpContextBase httpContext)
{
// check LDAP to verify that user has
// a role that's linked to `functionName`
}
}
Next you can use this attribute on your controllers and/or methods:
[AuthorizeWithLDAP("functionName1")]
public class BlogController : Controller
{
....
[AuthorizeWithLDAP("functionName2")]
public ViewResult Index()
{
return View();
}
}
The controller is now only accessible to users whose role are linked to functionName1 and the method is only accessible to users whose role are linked to functionName1 and functionName2

Handling data access in multi tenant site

I would appreciate some pointers regarding data access/control in a MVC based multi tenant site:
Is there a better/more secure/elegant way to make sure that in a multi tenant site the user can handle only its own data.
There are number of tenants using same app: firstTenant.myapp.com, secondTenant.myapp.com...
//
// GET: /Customer/
// show this tenant's customer info only
public ViewResult Index()
{
//get TenantID from on server cache
int TenantID = Convert.ToInt16( new AppSettings()["TenantID"]);
return View(context.Customers.ToList().Where(c => c.TenantID == TenantID));
}
If a user logs in for the first time and there is no server side cache for this tenant/user- AppSettings checks in db and stores TenantID in the cache.
Each table in database contains the field TenantID and is used to limit access to data only to appropriate Tenant.
So, to come to the point, instead of checking in each action in each controller if data belong to current tenant, can I do something more 'productive'?
Example:
When firstTenant admin tries editing some info for user 4, url has:
http://firstTenant.myapp.com/User/Edit/4
Let's say that user with ID 2 belongs to secondTenant. Admin from firstTenant puts
http://firstTenant.myapp.com/User/Edit/2 in url, and tries getting info which is not owned by his company.
In order to prevent this in the controller I check if the info being edited is actually owned by current tenant.
//
// GET: /User/Edit/
public ActionResult Edit(int id)
{
//set tennant ID
int TenanatID = Convert.ToInt32(new AppSettings()["TenantID"]);
//check if asked info is actually owned by this tennant
User user = context.Userss.Where(u => u.TenantID == TenantID).SingleOrDefault(u => u.UserID == id);
//in case this tenant doesn't have this user ID, ie.e returned User == null
//something is wrong, so handle bad request
//
return View(user);
}
Basically this sort of setneeds to be placed in every controller where there is an access to any data. Is there (and how) a better way to handle this? (Filters, attributes...)

I choose to use action filters to do this. It may not be the most elegant solution, but it is the cleanest of the solutions we've tried so far.
I keep the tenant (in our case, it's a team) in the URL like this: https://myapp.com/{team}/tasks/details/1234
I use custom bindings to map {team} into an actual Team object so my action methods look like this:
[AjaxAuthorize, TeamMember, TeamTask("id")]
public ActionResult Details(Team team, Task id)
The TeamMember attribute verifies that the currently logged in user actually belongs to the team. It also verifies that the team actually exists:
public class TeamMemberAttribute : ActionFilterAttribute
{
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
base.OnActionExecuting(filterContext);
var httpContext = filterContext.RequestContext.HttpContext;
Team team = filterContext.ActionParameters["team"] as Team;
long userId = long.Parse(httpContext.User.Identity.Name);
if (team == null || team.Members.Where(m => m.Id == userId).Count() == 0)
{
httpContext.Response.StatusCode = 403;
ViewResult insufficientPermssions = new ViewResult();
insufficientPermssions.ViewName = "InsufficientPermissions";
filterContext.Result = insufficientPermssions;
}
}
}
Similarly, the TeamTask attribute ensures that the task in question actually belongs to the team.

Since my app is using subdomains (sub1.app.com, sub2.app.com.....) I basically choose to:
a) use something like the following code to cache info about tenants and
b) to call an action filter on each controller as suggested by Ragesh & Doc:
(Following code is from the blog on : http://www.developer.com/design/article.php/10925_3801931_2/Introduction-to-Multi-Tenant-Architecture.htm )
// <summary>
// This class is used to manage the Cached AppSettings
// from the Database
// </summary>
public class AppSettings
{
// <summary>
// This indexer is used to retrieve AppSettings from Memory
// </summary>
public string this[string Name]
{
get
{
//See if we have an AppSettings Cache Item
if (HttpContext.Current.Cache["AppSettings"] == null)
{
int? TenantID = 0;
//Look up the URL and get the Tenant Info
using (ApplContext dc =
new ApplContext())
{
Site result =
dc.Sites
.Where(a => a.Host ==
HttpContext.Current.Request.Url.
Host.ToLower())
.FirstOrDefault();
if (result != null)
{
TenantID = result.SiteID;
}
}
AppSettings.LoadAppSettings(TenantID);
}
Hashtable ht =
(Hashtable)HttpContext.Current.Cache["AppSettings"];
if (ht.ContainsKey(Name))
{
return ht[Name].ToString();
}
else
{
return string.Empty;
}
}
}
// <summary>
// This Method is used to load the app settings from the
// database into memory
// </summary>
public static void LoadAppSettings(int? TenantID)
{
Hashtable ht = new Hashtable();
//Now Load the AppSettings
using (ShoelaceContext dc =
new ShoelaceContext())
{
//settings are turned off
// no specific settings per user needed currently
//var results = dc.AppSettings.Where(a =>
// a.in_Tenant_Id == TenantID);
//foreach (var appSetting in results)
//{
// ht.Add(appSetting.vc_Name, appSetting.vc_Value);
//}
ht.Add("TenantID", TenantID);
}
//Add it into Cache (Have the Cache Expire after 1 Hour)
HttpContext.Current.Cache.Add("AppSettings",
ht, null,
System.Web.Caching.Cache.NoAbsoluteExpiration,
new TimeSpan(1, 0, 0),
System.Web.Caching.CacheItemPriority.NotRemovable, null);
}
}

If you want to execute common code like this on every Action in the Controller, you can do this:
protected override void OnActionExecuting(ActionExecutingContext filterContext)
{
base.OnActionExecuting(filterContext);
// do your magic here, you can check the session and/or call the database
}

We have developed a multi tenant application using ASP.NET MVC as well and including the tenant ID in every query is a completely acceptable and really necessary thing to do. I'm not sure where you are hosting your application but if you can use SQL Azure they have a new product called Federations that allows you to easily manage multi tenant data. One nice feature is that when you open the connection you can specify the tenant ID and all queries executed thereafter will only effect that tenants data. It is essentially just including their tenant ID in every request for you so you don't have to do it manually. (Note that federating data is not a new concept, Microsoft just released their own implementation of it recently)

How do you access an asp.net code behind session object member variable in javascript?

I have a class that handles all of my session variables in my asp.net application. Moreover, I sometimes store objects in the session variables so as to allow me to code very similar to a normal .net application.
For example, here is an object in a session variable:
public cUser User
{
get { return (cUser)HttpContext.Current.Session["CurrentUser"]; }
set { HttpContext.Current.Session["CurrentUser"] = value; }
}
And here is the instance of MySessionClass:
public static MySessinClass Current
{
get
{
MySessionClass session = (MySessionClass)HttpContext.Current.Session["MySessionClass"];
if (session == null) {
session = new MySessionClass();
HttpContext.Current.Session["MySessionClass"] = session;
}
return session;
}
}
So, in my code behind aspx page, I would just do something such as
int userID = MySessionClass.Current.User.UserID;
This works great and I love it. However, I want to apply the same principle in javascript from my aspx page:
var userID = <%=MySessionClass.Current.User.UserID%>;
However, when I access that webpage, I get an error saying that it does not recognize the MySessionClass object.
So, given the context that I am in, what would be the best way to reference that UserID variable, from the object, from the session, in javascript? Maybe my syntax to reference it is off or I am going at it the wrong way. Any help would be appreciated, thank you.

Since you've defined it as a static member, you would need to qualify your reference with the page type:
var userID = <%=MyPageType.MySessionClass.Current.User.UserID%>;
That should be enough.

How to get userID for username in ASMX webservice

I'm trying to store a user's post into an access database through a web method. I want to store the logged-in user's username, user's post, and the post datetime.
So far, I can store an existing user post by hard coding. But I want to store posts by any logged-in users. I was told I need to get userID for username.
Thus, I've found and tried adding the following codes:
//GetUser() returns current user information
MembershipUser user = Membership.GetUser();
//Returns the UserID and converts to a string
string UserID = user.ProviderUserKey.ToString();
When I tried debugging with breakpoints, the first one was okay. But for the second one, VS 2010 said that "object reference not set to an instance of an object." How do I fix it?
VS suggested adding "new," which didn't work. It also suggested to catch NullReferenceException, but I don't know how to use the codes they provided:
public class EHClass
{
void ReadFile(int index)
{
// To run this code, substitute a valid path from your local machine
string path = #"UsersDB_in_App_Data";
System.IO.StreamReader file = new System.IO.StreamReader(path);
char[] buffer = new char[10];
try
{
file.ReadBlock(buffer, index, buffer.Length);
}
catch (System.IO.IOException e)
{
Console.WriteLine("Error reading from {0}. Message = {1}", path, e.Message);
}
finally
{
if (file != null)
{
file.Close();
}
}
// Do something with buffer...
}
}
Can you give me suggestions of what I need to do, or an alternative way to go about getting userID for username?

You didn't indicate what type of MembershipUser you have, but the ProviderUserKey is totally dependent on the underlying data store.
For example, the sql membership provider stores this value as a GUID.
If there is a possibility that this property won't contain any useful data, then you need to test it for existence before accessing it:
//Returns the UserID and converts to a string
string UserID;
if ((myObject != null) && (myObject.ProviderUserKey != null)) {
UserId = myObject.ProviderUserKey.ToString();
} else {
UserId = String.Empty;
}
In addition, unless you are using WSE in a straight asmx web service, I don't think that the memebership provider will have any valid data to operate on.
If this is the case, you will probably need to switch to WCF or implement WSE (NOT recommended).

The exception you're getting means that either myObject (the current user) is null or myObject.ProviderUserKey is null. I'd suggest that when you get to the breakpoint after myObject is set you should inspect the value of myObject and see whether it is null.
Depending on what is actually null affects where you look for the problem. If myObject is null then you'll need to look at the code to get the current user, and check whether someone is actually logged in etc. etc. If ProviderUserKey is null, consider whether you need this ID or would be better off with just using the username directly, check whether the membership provider actually provides that property in any meaningful way.

instead you can use this code directly....
string UserID = MembershipUser.ProviderUserKey.ToString();