How to save the userID with the session cookie - asp.net

When the user checks on "Log me automatically" in the login page, I have a problem that the user is logged-in on my asp.net application but the login info has not been read from database.
In the normal case (manual login) when the user attemps to login, if the login operation has been succeeded then the user info (id, privileges) is read and is saved in a session variable.
The question is: How to save the userID with the session cookie and how to login in the database when auto login.
Thanks in advance.

I suspect you're using the login control but implementing your own code to authenticate the user. To make life really easy, have a look at How To: Use Membership in ASP.NET 2.0 which will automate the "log me in automatically" feature (and many more).
If you're doing this another way, it would help to provide some sample code.

Related

Password Change from one location and Security

I am creating an asp.net web application with "Remember Me" option during Login and it has an Edit Profile module where users can change their passwords. Here is the scenario.
I logged into the website from Machine A clicking "Remember Me". So I am logged in and since a persistent cookie is created I dont need to login the next time
until my forms authentication times out.
I logged into the website from Machine B using the same account details I used above and from this machine, I changed my password. In this case How can I make the user in Machine A to login again? (Since my credentials have changed). The same scenario can happen if someone gets any user's credential and uses the application.
Thanks
You have to save the last credentials modification date in your database.
When a user try to consult a page of your website, you have to check the date specified in the cookie.
You can also make an AJAX system that verify each minute if any changes are done and, in that case, verify the validity of the credentials.
If the latest date is the "last credentials modification", then delete the cookie and ask the user to log by himself.

How do you unauthenticate User.Identity

Within an ASP.Net application I am working on, the process is as follows.
The user logs in.
If this is the first time the user has logged into the system ever, it authenticates the user then redirects to update the password
If the user updates the password, they continue on without problems
However, if the user cancels out of updating their password the user is redirected back to the login page.
Now I want to be able to unauthenticate the user at this point #4 if they deicde not to update their password. How would I go about doing that?
Check this question in SO. It contains the answer to your question and a lot more useful information:
What is the difference between Session.Abandon() and Session.Clear() in ASP.Net?
Edit: and just to be more specific, Abandon is what you're looking for.

how about allow the user login at the sametime?

In my appliation,all pages are protected,so they must login to visit the pages.
And the admin of the system can add users.
Now some people told me that I have to prevent people login at the sametime using the same account.
That's to say if there is a user named "John" logined to the system,so other people cannot login with "John" again event he know the password.
Also,if one user find that someone have logined use the account he wanted,he can make the former user offline. If so I have to judge if the current user have been offed ornot in each page. This is not a work can be done easily.
I wonder if this is necessary?
Since I found so many websites nowdays do not limit this,for exmaple,you can use the same account login your gmail/stackoverflow/yahoo and ect in different machine at the same time.
So Any one can give me a suggestion?
Update:
Now,we use the asp.net's form authenciation,(we do not use the membership yet). And in the t_user table in the databse,we have a column named "isOnline" and "last_login_time".
When user login,we set the "isOnline" to 1,and store the login time.
When another user try to login again,we check the "isOnline" and the time:
if("isOnline"==1 && DateTime.now-LastLogiTIme <40min) // where the 40 min is the form authenaication timeout.
thisAccountHasLogined=true;
But suppose a user logined yet,then he clean the browser cookie,then if he refresh the page,he will be redirected to the login page,but not he can never login again before the form authentication time out because the "isOnline" in the db is 1 and the time span from his login to now does not large than the form timeout.
I am confused.
In some scenarios, I could understand not having multiple logins, but in reality, I have never had to implement it.
Unfortunately, I do not believe there is a standard mechanism for determining if a user is already logged in and this would need to be done by additional logic. In our application, we use a database for storing session information and using this, it would be a simple process to see if a session already exists within this for the user and not allow login if so.
Update
I was interested in this myself and found this;
http://msdn.microsoft.com/en-us/library/system.web.security.membershipusercollection.aspx
and this
http://msdn.microsoft.com/en-us/library/system.web.security.membershipuser.aspx
Using those, it may be possible to get this information with the .IsOnline() However, this does make the assumption you are using standard asp.net membership
the table where you store user name and password add a column status
when a user attempt to login update status to "Online" when logout update status "Logout"
During login check status, if status is online , terminate process. This may be an approch to implement this, hope it will help you

ASP.net Memberships Force User Offline (as admin)

I am looking for a way to distroy the ASP.net membership session for a specific user. The reason I am doing this is as an admin I want to delete a user. This works fine, but if the user already has an active session, he is still marked as "online" until this session dies (I verify each time by using Current.User.Identity.IsAuthenticated).
How do I go about killing a session based on the user it's authorized as. This way when I do Memberships.DeleteUser(username) I can also do Sessions.KillByUser(username)
Thanks in advance
I ended up following their suggestion and using the following method, for anyone who has the same issue:
http://www.chillaxen.com/2011/02/asp-net-force-a-user-offline-as-admin-destroy-a-session-by-username/
How about adding a HttpModule which intercept PostAuthorizeRequest event: Check the users' credentials against a global list of IDs you want to "destroy". If there's a match, kill the users session.
As Jakob suggested Or you can try this...
in the Global.asax check if the logged in user is in the 'List of user to be made Offline' then logout the user by forms authentication or deleting the cookie.

on session start event

I'm building a web application: some pages will be accessible by non logged-in users (demo and sign-up pages) and others will only be accessible by logged-in users (actual application). In the global.asax file, I'm currently handling the session start event by loading some variable from a query that's based on the UserID. What will happen when a non-logged in user looks at a page? I guess my question is really about how to handle the session start event when it's a logged-in user, when it's not and when a user logs in. I want a certain number of queries to run only once per session, after the user logged in.
Thanks.
I would suggest to implement Forms-Based Authentication, instead of to handle authentication via session. An example can be obtained from here:
http://support.microsoft.com/kb/301240
Don't confuse "login session" with "session state". Session state has nothing to do with whether the user is logged in.
If you want some queries run when the user logs in, you should run them when the user logs in, not in Session_Start.

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