How to secure my AngularJS and Web Api application - asp.net

I am using AngularJS with ASP.NET Web Api server side. Seems to me like authentication has now become a breeze? Or is this too good to be true?
So I'm thinking of using the Web Api's "Individual User Accounts" authentication. And I am thinking that is all I need. As long as every request is authenticated and noone can get any data they shouldn't I shouldn't need to do much more right?
Or am I missing some key security fundamentals?

When it comes to securing the API you have two main approaches
Cookie based approach. This is the traditional way, where you use the standard form to authenticate the user and then set the form authentication cookie. All unauthorized request take the user to login page. If your API is always supported by UI front end to do login this method with work.
Second is using the authorization token in the header of the request. Once the user is authenticated he get a auth token, which he has to attach to every subsequent request in the Authorize HTTP header. Learn more about it here Individual Accounts in ASP.NET Web API . The advantage here is that you can expose your API without requiring a login page.
But remember when using the second approach, the auth token has to be stored on the client side as all subsequent request require this token. Look at this blog post Cookies vs Tokens. Getting auth right with Angular.JS to understand how to work with token.
Hope it helps.

Here's a great article about using Angular JS with WebAPI 2.0 token based authentication.
http://bitoftech.net/2014/06/01/token-based-authentication-asp-net-web-api-2-owin-asp-net-identity/

Related

Using both cookie and JWT tokens in ASP.NET Web/API app

I've seen a lot of articles that cover using JWT Tokens in API scenarios. How do I include the JWT Token in my request for a web page?
My ASP.NET Core app has both web pages and API methods so I want to use cookies for the web and token for API.
The way we do it here with Asp.Net, is our auth layer looks for either a cookie or an Authorization header. It pulls the token from either location. This article might be helpful:
http://auth0.com/blog/cookies-vs-tokens-definitive-guide
This takes some custom code, but its not too difficult really. Make your own AuthenticationHandler.
https://wildermuth.com/2017/08/19/Two-AuthorizationSchemes-in-ASP-NET-Core-2
That excellent article will guide you through every step of the process.

ASP.Net Web API Authentication using OAuth

We have planned to implement authentication in our API using OAUTH. For this purpose I read so many articles on web to explore it. After read these articles what I am understanding is
Send credentials to authorization server and after successful
authentication it will send you the access token.
Use this access token for further calling of your api methods.
To authenticate our api user needs to pass the following parameters.
Authorization Token
Employee ID
What I am thinking is to pass these values via request headers. Problem is that these request headers can easily be viewed in browser console and someone can misused it easily. Please suggest Is this the right way to authenticate api or we used something else for this purpose?

Challenge while setting up seamless authentication across MVC and Web API Layer

I work on an application where I have a separate MVC layer and Web API Layer, both have the same authentication mechanism, I have chosen the individual accounts authentication option while adding the projects. The web api service layer will be directly accessed by some other mobile clients also.
But when the user logs in through MVC he should be able to access Web Api seamlessly, but I don’t want to really pass the username and password from MVC to the Web Api layer, I am told it is a bad practice. but i need to authenticate and authorize my user, so the only option i have thought of is to have a default account at Web API level to issue tokens, and this will be called from MVC post the authentication and a token will be returned which is written to a cookie in the client. Now the Ajax calls from the UI can use this bearer token and get the job done.
The only glitch I have here is that, because I am using a default account I need user details again for authorization at service level, though I am doing authorization at my UI level, the user can spoof the system. I was lost here and came up with a solution like, when the user logs in to MVC will send across user details also along with the call to get the WebAPI token and issue another token to the user so that the user uses both of the tokens to make a call to web api from MVC.
I am not sure if this works or if it is even the best way. I just wanted to check, how I should go from here. Any help on this will be really great.
This is a really good example of integration - I know they use Angular as the client but you can learn from this:
http://bitoftech.net/2014/06/01/token-based-authentication-asp-net-web-api-2-owin-asp-net-identity/
Check this section to see how they decouple the API from the front end (Part of the same article).
http://bitoftech.net/2014/09/24/decouple-owin-authorization-server-resource-server-oauth-2-0-web-api/

Authentication and authorization related doubts with asp.net web api

I have to start a new project to be developed in MVC 4 and Web API. I have prior experience with MVC 4 but with Web API this will be my first project. I understand that web api is there to be consumed by different platforms.
I have a few concerns related to web api. I am presenting them to you guys as following:
1) My first concern is related to user authentication. I looked into this SO question and followed the link1 and link2 given in the selected answer. I still have a couple of questions:
a) When we do user authentication through Form Authentication we create a cookie, that track if the user is authenticated or not, but with web api we do not store cookie, instead user credentials are passed in content header. I didn't get how user's logged in status is tracked in this case ?
b) My another concern is related to restrict unauthorized access, which I think I can find find out in link 1 and link2 provided above, if I am not wrong.
c) I looked at the Edward Brey answer (in the same SO question) as well for authentication but I didn't get the idea completely.
2) My second doubt is about mixing Form authentication and Basic Http authentication. Is it possible that for login I use forms authentication and then for consuming web api I use basic http authentication? If yes then please guide me.
My questions may sound inappropriate but please bear with me
1.a) Restful APIs are stateless, so you are not keeping track of user's logged in status, rather you are sending credentials which are verified for each of the requests
1.b) Yes, if not there are number of articles on web for that. Authorization Filters can help you in achieving this.
1.c) In short, he has mentioned simple logic to authorize user before executing any of the methods in your API. Call EnsureAuthenticated before executing any of the methods in a controller, or put that logic in you Authorize filter.
2) Yes you can do it. In Restful API's each call can be a new instance and you can pass in credentials with api requests whichever you are making.
If you go in discussion of Link 1 that you have provided, you will see:
In our specific case, the server generates the auth token by encoding
the concatenated username and password as Base64 (the reverse of what
is described in the article) and sending it back to the client via a
HTTP header when it performs their ‘log in’ action. The clients then
store this auth token and send it with each subsequent request that
requires it.
If the format of the auth token is well known (as it is in my case),
you could also just generate this yourself on the client and send that
without having the server do this work.
You can use your login to generate an authentication token for client, which you can use to send attached to your web api requests.

MVC 4 Web Api Security

I am very new in web api security. I have used form authentication technique. when user logs in, a token is created and stored as a cookie in user's web browser. On each request the token is varified and if user is authenticated and authorized user is given access to the service.
but I think this approach does nothing in web api security. cookies can easily be copied and pasted in other browser and anyone can get the service.
I am thinking to use App key and secret along with form authentication. I am not suggested to use third party service like Oauth for authentication. I am not Sure about the Implementation of app key and secret that how it exactly works.
Please provide better way to secure my web api wihtout using third party services and to prevent cookie hijacking etc. What actions are performed to build a strengthly secure web api.
The forms authentication is good enough. You can also do the following:
Use anti-forgery (antifrogery) tokens. Check this or this
It will also be great if on sensitive actions you check if the call to the function was made from the same site or not.You can implement your own action filter for this. (check if the referral site is your site, or the expected site)
Edited:
Thanks guys for your comments. I guess you are right. Well authentication cookies in ASP are created as httpOnly cookies which means even if the site had some XSS vulnerabilities it will still be safe and cant be stolen. I would also suggest to use https everywhere if the site is used for sensitive operations (like a bank) to make sure the cookies are perfectly safe.

Resources