MVC Membership change UserId Value - asp.net-mvc

Question

Using MVC when registering a new user a record gets created in webpages_Membership and UserProfile
The UserId by default gets created as sequential number 1, 2, 3...
my model
public class UserProfile
{
[Key]
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int UserId { get; set; }
}
When I go to edit the record in the URL it shows /profile/1
I want to change the id's value to something random e.g. profile/f8934hre987f8987f9f8 for security reasons.
Same thing I want to generate random number when details gets viewed by members so instead
/details/1 want it to be /details/783787483743874873
The ViewModel for displaying the details contains Id field as a primary key which is also gets generated sequentially.
I read using [GUID] is not great for performance.
Advice how to change it without affecting the performance? Suggestions. Thank you.
EDIT
Have similar like groupon site, when user attempts to edit his/her profile instead of showing /edit/1 have something like:
So user doesnt know how many records in the database or what record number the user is.

Answer 1

I am not 100% sure what you mean by something random. I am assuming that you mean encryption. Please take a look at this MSDN link for the details on encryption.
After that ,you can have your action method like /detail/{encrypteduserId}
Then you can have action method like below
public class Detail(string id)
{
var decryptedUserId = GetDecryptedId(id);
// GetDecryptedId gives the decrypted information.
// You can implement it based on the MSDN link
// You can use decryptedUserId to run queries on the database.
}
This way you can achieve your goals without making schema changes. This seems like a minimum possible friction approach.

Answer 2

There is no security benefit to having a random user id, so long as your site implements proper controlled access. That is, nobody should be able to access /profile/1 except the user with a user id of 1 (or another user who is authorized to do so, such as an administrator). All other users should get an error.
An even better approach is to not use an id at all. Simply get the current users ID and show the profile of the currently logged in user. Then user with userid 1 just goes to /profile and they see their profile, and user with an id of 2 goes to /profile and they see their profile and there is no way for one user to see the others.
That's not always possible however, for instance in maintenance screens where an admin is viewing other users profiles, but in that case only the authorized admin should be able to do that.
Obscuring the userid is a false sense of security, since the id will be visible anyways. You are simply fooling yourself if you think this adds any security value, unless you haven't implement proper security in the first place, in which case it's just hiding your real problem.
It also adds needless complexity, and confusion. It's equivalent to saying "I want to change the address of my house to a random number for security reasons". Think of all the problems that would cause, for dubious results.

Answer 3

Having the User ID displayed in the URL is a genuine security concern, be it a simple integer user id or some GUID (if that GUID can be used to identify a user). This is especially true in cases of Transport layer security (HTTPS) where the URL is not encrypted like the content is.
Here are a couple of ways I can think of going around this:-
1.) As suggested by Erik above, use User.Identity.Name to identify the currently logged in user. This wouldn't however work for the administrator accessing another member's profile. It would also not work for unauthenticated scenarios.
2.) Instead of creating a direct hyperlink, create a form which posts the user id as part of a custom type (model). Then use model binding to access the User ID as a property of the custom model object in the Action method. In this case, the user ID is submitted as part of the form and hence is transported over the wire encrypted (if HTTPS) and not visible in the URL. This would work in both cases where a member is trying to access his/her own profile, or when an administrator chooses a profile to access on screen.
An example of scenario 2::
public ActionResult EditProfile(UserProfile userProfile)
{
bool success = false;
if (User.Identity.IsAuthenticated)
{
if (ModelState.IsValid)
{
if (WebSecurity.UserExists(userProfile.UserName))
{
// your code to update profile here.
}
}
}
if (success)
{
ViewBag.Message = "Profile updated successfully.";
}
else
{
ViewBag.Message = "Profile not updated:";
}
return View();
}