Is it possible to share sessions across subdomains which are different applications? - c#

Is it possible to share sessions across subdomains which are different applications without using Sql Server Session mode? I've implemented this concept with help from this link:
What options are there for sharing data across subdomains?
However is it possible without Sql Server mode may be using in proc etc?

You won't be able to do this using InProc, each application will have its own memory space.
You could set up a web service to get around the issue, although I find this solution to be more of a hack.
You could alternatively use a key/value store database or some flavour of NoSQL.
A custom session state provider would be a more elegant solution.
MongoDB ASP.NET Session State Store Provider

Related

Is there a way to have same session for two web form apps in same solution?

Is it possible to have same session in two web form projects in same solution? I did find a something in here, but it doesn't work and it does not save the session data of one web form project to another project.
The only way to have some share session is to use a common database to save that session data there, manually - not using any kind of ready to use asp.net modules.
And you must also take care the cookie to been able to connect the same data to the users across the different sessions - or to use the login data of the two applications to make that share session...

Handling sessions for scalability

I'm currently making a site that is very database oriented somewhat like Stack Overflow. My question is how to handle sessions that will travel across several servers(I plan on using AWS servers for auto scaling).
Currently I am under the belief that I should not use Forms Authentication for scalability and speed purposes. Instead I would have a table in the database called sessions that stores the following information: SessionID, UserID, ExpDate, CreateDate, IP, Status('LogedIn', 'LogedOut', 'Expired').
My biggest concern would be security from the stand point of cookies and not having the experience to see a bottle neck scenario when I have a lot of server running.
Please provide me with your insight. I'd also like to know how others and Stack Overflow are handling this dilemma.
FYI: For the same reasons I'm using PetaPoco instead of Entity Framework as I was able to shave off around 600ms by doing so.
Thank you for your help!
I am not aware of any scalability issues with using Forms Authentication. Essentially, it encrypts an authorization token into a cookie and the cookie is presented to the server on each request. Using cookies instead of in-process session does allow for scalability as it is not tied to any one specific server.
The encryption uses a machineKey value that is stored on the server so breaking the encryption would require getting a hold of the machineKey.
In general, I try not to implement my own authorization and instead try to stick with out-of-the-box solutions that have been tested.
Your approach of using a session store still requires the use of a cookie to store some kind of pointer to the session store. Depending on your implementation, it might be easy to guess this information and easily impersonate someone else.
EDIT:
Since you are running on AWS, I would suggest you take advantage of ElastiCache to reduce the number of DB hits.
I know from a caching perspective that StackOverflow was built using Redis.
Check out Which tools and technologies are used to build the Stack Exchange Network?.

best practice for DAL and configuration on Multi-Tenant isolated DB

My company holds a dozen websites and isolated DBs (identical schemas).
every customer has its own website (different app pool) and DB.
every website has its own configuration, several connection strings, but they all have same schema for configuration.
cust1.domain.com
cust2.domain.com
cust3.domain.com
We would like to merge all websites to one (single app pool) and stay with isolated DBs for security and large amount of data reasons.
what is the best practice for designing a DAL and configuration of it?
what are the implications of it, if large amount of tenant will be on the same time? does one application pool can manage this situation or it can be managed somehow?
BTW, we are using asp-membership for users authentication.
Thanks in advance,
Eddie
Use Application_PostAuthenticate event in global.asax to load the correct database and then close the connection in Application_EndRequest
One option is to use the profile in membership and store a piece of information that will allow you to determine which of the actual db's they should be connecting to. Downside is that you will need to store this piece of information for the duration of the users session so either a cookie or session variable is likley to be needed.
The implications of one site vs many depends a lot on your environment and application, do you currently have the multiple sites on a single box or do you have a web farm? do you know the number of concurrent users for each site, the amount of traffic? Performance monitor can help you here to see how busy each site is but you may need more invasive logging to determine metrics such as concurrent users. I found this server fault question around IIS 7 performance which may be of help
You can try 'Shared DataBase With Different Schema' from multi tenant data architecture . In your DAL you can choose specific schema which perticular to current user. Simple and secure in this way
Continue reading http://msdn.microsoft.com/en-us/library/aa479086.aspx

Retain session when calling from a different website

I have two website consider it as website1 and website2.
In website2 there is a login page .When a user click on the login button it will call a HTTPhandler in website1 to authenticate user.On successful authentication user information will be stored in a Session variable from handler.
Then it will redirect to a page page1.aspx in website1.But the previously set session is not available in the page1.aspx .What will be the issue?
I checked the session id in first request(when calling handler in website 1 from webiste 2) and Second request( redirecting to the page1.aspx from the handler) the session id is different.
How can i retain the session data?
You need to store session data in another process shared to both web site.
You can do it intwo different ways:
Configure an SQL server
Configure SessionState service, a Windows service used to share informations.
In both cases you have to change both web.config files to support the new session mode.
I.e. to use SQL:
Prepare a database (from command prompt):
cd \Windows\Microsoft.NET\Framework\v4.0.30319
aspnet_regsql.exe -ssadd -E -S localhost\sqlexpress
Modify web config as following:
<sessionState mode="SQLServer"
sqlConnectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;Initial Catalog=Test" allowCustomSqlDatabase="true"/>
You don't need to change your code.
Correct me if I an wrong, AFAIK different domains cannot share a single session. One way to handle this is to carry the data to the other site through cookie [encrypt the values for security], then copy this cookie value to the session in the other site receiving it and destroy the cookie.
And if the sites are in different servers you need to handle the "sticky session" so that servers share the session.
This situation sounds kind of similar to one I have experienced and worked on before, where one web application acts as the login page while another is the actual app where all your work is done. I can describe what I did in the hope that you find it useful.
Like you I had one web app which had the login page (so in your example this would be website2). When the login form submitted I then redirect to a fake Login.aspx page in website1 - this is where we differ I think as I'm not sure of your specific reason for using a HttpHandler.
In my case the website2 Login.aspx page is actually just the way into the web application; it has no markup, just code-behind which will authenticate the user, perform setup (e.g. set session variables) and then redirect to another page such as Homepage.aspx. This particular scenario has worked for me, so maybe your problem revolves around the use of a HttpHandler though I would not be able to tell you why.
In order to retain the same session date across two different servers running ASP.NET web applications you must configure your session state to be managed out of process. This means the actual session state data variables will be stored outside of worker process and in another process that is able to make the session data available to other machines.
To achieve this you can configure your application to use SQL Server to store session state and make it available to multiple servers in your farm. The TechNet article Configure a SQL Server to Maintain Session State (IIS 7) provides details on hor this is done in IIS 7.
If you are using IIS 6 then the steps to configure are somewhat different and I can provide further details on this if needed.
In order for this to work you do need to ensure that both servers are running applications within the same domain, e.g. myapp.com, otherwise the ASP.Net session cookie will not be passed between the two servers. ASP.Net uses the cookie to lookup the session state stored in SQL Server and will therefore not find any matching session if the cookie is not passed on requests between the two servers.
i think IRequiresSessionState will not help because context is different.
once we had the same problem but that was passing asp session varibles to .net. How ever you can do it here also.
on both website create a page setsession.aspx
now if you are on page say web1/page5.aspx and want to go to web2/page3.aspx
you redirect to web1/setsession.aspx?togo1=web2/page3.aspx
in both setsession.aspx logic in to extract sessiondata and place them in querystring
so the web1/setsession will redirect to web2/setsession.aspx?sess1=value1&sess2=value2&togo=page3.aspx
web2/setsession.aspx will check for togo querystring and if found will extract all querystring name and value will set them in session and will then redirect to togo value.
you need to differentiate togo1 and togo carefully.
Session sharing between websites is going to require hand-coding. You could hack the asp.net framework to get this working, but I feel that this is not a clean way of achieving what you set out.
If user authentication is all you are doing from website, is it possible to use alternative? Single Sign On mechanisms will help you out here.
Something like SAMLSSO could help you in this case.
You have two websites which are hosted on different servers, it means you have two different processes running on separate machines, so sessions will be definitely different. Same session can't be shared across processes because by default asp.net support in-memory session.
Here you would need to think about storing sessions information which can be shared between two processes (i.e. out of process). Ideal way to store sessions information in databases. For this you can consider Stefano Altieri code sample above.
I don't think you really want to share session information between two websites at all. From what I can gather from comments, what you're really trying to do is have a user authenticate in one website (give you a username and password which are validated) and then have that "logged in" state transferred to another website which doesn't handle authentication for itself.
What you are describing is the Delegated Authentication model.
In this model, your application hands-off authentication to other systems which it trusts to provide information about users.
There are two well-known protocols which provide this mechanism:
OpenID
This is intended to facilitate users logging in with their own identity providers (Google, Facebook, Microsoft Account). It's a very good choice if you're running a public-facing website, as most users will already have an account they can log in with.
WS-Federation
This is intended to facilitate users logging in with identity providers which are managed by known trusted parties, such as partner organisations.
From version 4.5, the .NET Framework has built-in support for WS-Federation via the Windows Identity Foundation component (and is also available for earlier versions as a separate download). This automates the task of delegating your authentication to an Identity Provider.
It also provides components for you to write your own Identity Provider, should you want to create your own, but you shouldn't have to; you can find various existing implementations to perform this job for you.
The problem you're trying to solve is a very difficult one, especially trying to make it secure enough to be reliable. The good news is that smarter people than you or I have spent years working out very clever ways of doing this. You should use what they have done and not try to cobble together something out of Session state.
In the long-run it's best to let the smarter men do the hard work for you.

Asp.net MVC4 Storing sensitive user data

I have a Asp.Net MVC4 website which can connect to multiple databases depending on the user's login credentials. In order to get the database access list for the user, I have to perform a few complex joins when they login. To avoid having to do this more than once, I am currently encrypting and storing the database ID in a cookie. I now realize that this may not be a good idea and even strong encryption may be broken. In addition, the encrypted cookie is transferred around on every request increasing traffic. I am now thinking about using the HttpContext.Current.Cache to store the data instead. Can anyone comment on whether this is a good idea. I would also be interested in knowing if there are better options out there. My website is not deployed on a server farm right now but what would be the implications if I were to use a cache and a server farm in future?
Based on your requirements (i.e. keep a hold of sensitive user specific info across a session), the correct place is for this is the SessionState. AFAIK sessions states can be shared across multiple web servers so if you did use a server farm you wouldn't need to change anything.
Session is right container for user sensitive data. Or you can store it in database and get it there by some identifier that is stored in session(it is useful if you store large amount of data).

Categories