In our project we need to consume a TokenMaster service which passes us a token for a valid request and also the token is valid for exact on hour from the time of response and expiry time is also included in the response received. The token provided is a JWT token.
I have two approached here:-
a.) To use a static field and store a Pair<String-Token, ExpiryTime>, while sending a request we'll check if the token has expired or not and based on that we will take make a call for a new token or use and existing one.
b.) use an existing library that can do this for us i.e. refreshed token automatically.
My question is do we have a library that can do this(refreshing token) automatically for us. Our application is a spring boot application developed in Kotlin.
Related
Iam new to spring security and i was going through spring boot jwt and the process but i dont know how to use logout feature through jwt .
For example when a user click logout at after that time using that token we can not access the secured Rest end points.
Now i want is implementation of logout functionality using JWT(Spring Boot Rest Api)that is used in real time projects and the code for it.
Please if any one can provide me the github link to the solution
or can send me the code at
ag.rajat113#gmail.com
and anything related to latest spring security projects real time (Backend)
and also of oAuth2 material please send me i need this
Thanks.
On logout, you can perform the following actions
Remove the token from the client
You can remove the token from Client (Local storage, Session/Cookie). Note that it will not prevent the client access as you removing from only client side and for server, it is still valid Token
Maintain Token blacklist
When a client performs logout action. Add that token to blacklist and for next request check token is in a blacklist. If yes then prevent the access. As you have to check for every request it will be costly for large applications
Short expiry time
If you keep the token expiry times at short enough intervals and have the running client keep track and request updates when necessary, It will be working as a complete logout system. The problem with this method is that it makes it impossible to keep the user logged in between closes of the client code (depending on how long you make the expiry interval).
You can also refer this for Details
We have a restful API developed on spring-boot V1.5.7 and it is secured by OAuth with "password" grant type. We are using only access token, the refresh token is not being used. The validity of access token is set to 15 mins. Initially, we hit the token endpoint and get the token and consuming the services. Though the services are being consumed very frequently the access token is getting expired after 15 mins. What we are expected to do is, when the services are not being called for 15 mins only then the token should be expired.
Can anyone please help me on this?
Looks, First we need to know Why we used access token?
Access token is used for accessing protected resource. It has a validity periods say for example 1min, 10min etc. After that time, token becomes invalid. To get a new valid token you should use refresh token.Though you can get a completely new token using your username and password. Even if you invoke any api within the expiry time though, the token invalid after the expiry time. If you don't invoke any api within the expiry time, token becomes also invalid. This is expected behavior.
Why this is expected?
Suppose you get an access token from server and access protected resource from server with access token. Somehow man in the middle get the token by sniffing packet. Then intruders can get easily access the resource as you can and as much time he want's. So technically we can say that, your account is being hacked.
To prevent this attack, you should define a token validity periods that would be suit for your use case. So this is more secure than previous.
I would strongly recommended that allow refresh token for your system.
However You can also configure your system to reuse the token. This link may be a help.
You can use OauthRestTemplate (if you don't want to write your own logic) which will fetch a new the access token (using refresh token) after it is expired. There is no reason to not use refresh token if you are planning on using OAuth in your application.
I am quite new to JWT based authentication. And im quite confused about the refresh token mechanism. In my case, I have designed my application as,
1. User will login to the application, and when the login is successful then it will go to the authentication server and sign a jwt and will pass it to the client.
2. And then the client will store the refresh token and the short lived token in the local storage
3. Once the resource server is called the token will be sent through the header. and will get validated.
My question is, in which point should we request another token using the refresh token mechanism. Should we check whether the short lived token is invlaid before sending the request to the resource server. or should we get a new token once the validation fails in resource server? or is there any better way to handle this?
A Refresh Token is a special kind of token that can be used to obtain a renewed access token —that allows accessing a protected resource— at any time.
Although Access Tokens can be renewed at any time using Refresh Tokens, they should be renewed when old ones have expired, or when getting access to a new resource for the first time. Refresh Tokens never expire OR have very long expiration time.
I'm implementing an Auth server using Spring Security Oauth2. What I noticed is that when spring security saves the access token (using JdbcTokenStore) , the OAuth2AccessToken is serialized as which means the access token is self is saved as plain text. I have a couple questions about this.
1.) The token is never actually retrieved using the access token value. It is retrieved using a token id. Why is that?
2.) Is it Ok to hash this token since it is never retrieved using it's value?
3.) Do we actually need to generate the token id? Can we pass an extra information from the resource server to the authentication server to retrieve the token and validate it against the hash?
By default Spring stores the token in plain text. If you make a request to get a token again in the same browser, you will notice that Spring will return the same token as long as it is still valid.
1) This is not entirely correct. On the resource server, the token is read from the header and a PreAuthenticatedAuthenticationToken is created. Through several steps the token value is used to create the OAuth2Authentication. The key is a intermediate step, but only after you have resolved the token to an OAuth2AccessToken (see TokenStore.readAccessToken())
2) Personally I would hash the token before storing it in the database! This does however require you to implement/extend a TokenStore, since you need to override TokenStore.storeAccessToken() to save the hashed value, and TokenStore.readAccessToken() to hash the incoming token and find the hash in the database.
3) Typically the authentication server and resource server read the same database, and both ends up with a OAuth2Authentication identifying the user. If you want to hash, you just need to implement the store/read methods as described above.
I have implemented a solution like this with Spring Oauth2 1½ ago, so hashing tokens and refresh tokens is diffidently possible. In our case we ended up not using the resource server implementation from Spring Oauth2, because we get 20K requests every minute, and we wanted to delay resolving the token until the request has been validated, and use several layers of caching to avoid hitting the database on every request.
I have a Web API and AngularJS client. The API is using default authorization provider given by visual studio to generate the token on token request with grant_type 'password'.
The AngularJS client is able to get the bearer token from Web API by calling the token endpoint with credentials and later passes this token to perform authorized requests in the API.
When AngularJS sends the token on any authorized API call, how is Web API able to validate the token? Where does the token get stored?
I checked in Identity tables in SQL server, I could not find any fields to store this token information. I checked in the configuration file, it is not stored there either. Could you please help me in understanding this concept?
Raj,
By default the token is not stored by the server. Only your client has it and is sending it through the authorization header to the server.
If you used the default template provided by Visual Studio, in the Startup ConfigureAuth method the following IAppBuilder extension is called: app.UseOAuthBearerTokens(OAuthOptions).
This extension coming from the Microsoft.AspNet.Identity.Owin package makes it easy for you to generate and consume tokens, but it is confusing as it is an all in one.
Behind the scene it's using two Owin middlewares:
OAuthAuthorizationServerMiddleware: authorize and deliver tokens
OAuthBearerAuthenticationMiddleware: occurs at the PipelineStage.Authenticate, read the authorization header, check if the token is valid and authenticate the user.
To answer you questions WebAPI is able to validate the token thanks to the OAuthBearerAuthenticationMiddleware, it will ensure that the token sent through the authorization header is valid and not expired. And the token is stored only by your client, if the client loose it, it will have to request a new one.
I advise you to get deeper in the OAuth protocol, and instead of using the extension UseOAuthBearerTokens, take a look at UseOAuthAuthorizationServer and UseOAuthBearerAuthentication, it will help you to better understand how it works.
The generated token will most likely be a JWT (Get Started with JSON Web Tokens), which means it's a self-contained token that is signed with a secret/key that only the server or other trusted parties know.
JSON Web Token (JWT) is an open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. This information can be verified and trusted because it is digitally signed.
(emphasis is mine)
This means that when receiving the token the server can ensure that:
the token was originally issued by a trusted party by checking that the signature is valid.
the token is associated with a user that has permissions to perform the following request because the token itself contains information that uniquely identifier that user.
This type of approach has the side-benefit that the server does not need to keep track or store the generated tokens in order to validate them at a later time. Since no one else has the secret/key you can't modify the token without making the signature component invalid, which would then mean a faked token would end up being rejected by the server.
This is a simplified description of what happens, there are much more details around how to issue and validate tokens correctly. You should read the OAuth2 and OpenID Connect specification to learn more on the subject of token-based authentication.
Also note that I assumed a JWT token because it's the format that currently has the most widespread adoption to accomplish scenarios like these ones and it's also the token format to use in conjunction with OAuth2 and OpenID Connect. However, it's still possible to achieve the same with other token formats.