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how to delete a token JWT

I'm working on authentication on spring framework using JWT, bearer token.
public String generateToken(UserProfile authentication) {
// set the expiration time
Date now = new Date();
Date expiryDate = new Date(now.getTime() + jwtExpirationInMs);
// Generate token and return
return Jwts.builder()
.setSubject(authentication.getUsername())
.claim("roles","user")
.setIssuedAt(new Date())
.setExpiration(expiryDate)
.signWith(SignatureAlgorithm.HS512,jwtSecret)
.compact();
The above class generates a token and respond back to the user. My question is how I'm going to delete the token when a user issue a new token before the first token expire time; to revoke the first token when a user request a new token before the first is expired?

I don't think that's possible to do with JWT.
You could
Add the old one to some fast storage (like Redis or memcached)
Set some timeout on the value (a little big longer than the expire date of no longer wanted token)
Check if the token from request exists in your cache, if yes then reject it
basically, do the blacklisting
I'm not aware of any other solutions

If you use JWT, you can't revoque the token. Its validity is embedded.
When you want to revoke a token, don't use JWT. You must persist the token and check its validity at every request.
If you really want to use it, save it in db as if it's not independent and add a flag or a timestamp for validity.
Check JWT documentation : https://jwt.io/

Best practices for managing auth token

I am writing a REST client in Java using the HttpCLient , the REST API that I access needs an auth token for every REST action. This token is valid for 24 hours.
The way I am handling this now is calling a "getAuth()" method everytime I need to make a REST call which seems like an overhead on the auth server.
How can I conveniently store this auth token and manage its life cycle?
Are there any documented best practices?
I thought of the following solution
public class MySession {
String user;
String pass;
public MySession(String user, String pass) {
this.user = user;
this.pass = pass;
}
public getAuth() {
//user user, pass to get auth token
}
}
and then pass the sessions object to any class that nees the token. If the token is expired, just call this method again

For brevity I'll assuming you're calling an endpoint that you can't change. How you should implement will heavily depend on whether the token is app or user based (one token for all users on a shared app instance or one token per user).
If it's one auth token for the entire app:
Store it in memory along with a time-to-live timestamp (or alternatively catch the token expired error, request a new token and retry the original request), refresh it if it doesn't exist/is expired
If you're concerned about re-requesting API tokens after an application restart also store it in the database and load it at startup if it exists
If it's one token per user:
Store it in your user session, it's exactly what sessions are used for, if you're authing users then they'll have a session and the overhead is already there
If you don't want to re-request a token everytime they login store their current token in the DB and and load it into their session when they login

I'm assuming you are using OAuth for authorization. Whether you are using JWT or other tokens is irrelevant to this situation.
When performing authorization you will be issued an access_token with an expiration and, depending on the grant type you are requesting (Client credentials, Authorization code, Implicit, Resource owner), a refresh_token.
The client should keep the access_token and the expiration. The refresh_token, if issued, must be kept secret (beware of using the correct grant for your use case).
In subsequent calls, your client should not request new tokens on each call, it should use the stored access_token.
Once the API starts returning 401 Unauthorized, the access_token has probably expired. Your client should try to refresh the access_token using the refresh_token if you got one.
If you have no refresh_token or the refresh request also failed, because the refresh_token is no longer valid, you can perform a new authorization flow.
You can use the expiration time as a clue to know when to get a new access_token either through refresh or through a new full authorization flow. This will avoid the 401 Unauthorized. In any case, your client should have a fall back policy when this response is received after having used a valid access_token for some calls.

You can create a manager and store the auth-cookie during login in thread local like the code below. You can get the cookie from getAuth() as long as the thread lives.
public class Manager {
private static final ThreadLocal<String> SECURITY_CONTEXT = new ThreadLocal<>();
public static void setAuth(String auth) {
SECURITY_CONTEXT.set(auth);
}
public static String getAuth() {
return SECURITY_CONTEXT.get();
}
public static void clear(){
SECURITY_CONTEXT.remove();
}
}

I suggest you to use the following scenario:
1) First, call auth(username, password) rest api to get the auth token.
If the given credentials are okay then just send back the auth cookie to the client with HTTP 200 response code.
2) Then, you can call protected rest apis. You need to send auth cookie with your request each time.
3) Servlet filter (or something similar) checks each incoming request and validates the token. If the token is valid then the request goes forward to the rest method, if not you need to generate an http 401/403 response.
I suggest you not to write your own authentication layer. Instead of install and use an existing one. I suggest you OpenAM. It is a superb open source access management system.
I also suggest you not to open session on the server side for authentication purpose. If you have 10 clients then 10 sessions needs to be managed by server. It is not a big issue. But if you have 100 or 1000 or millions different clients than you need more memory to store sessions on the server.

If you are worried about too many hits to the database, then i'm assuming there is a lot of web activity.
I would not recommend using Session in your case, but rather store the token in a cookie on the client.
In a high traffic environment(which i'm assuming yours is), the use of Session can consume a lot of server memory, and scalability can be a concern as well, having to keep sessions in sync within a cluster.
As #Cássio Mazzochi Molin also mentioned, you can use an in-memory cache to store any user specific data and tokens. This will reduce the hits to the database, and also allow you to scale the application easier, when the need arises.

The de-facto standard is not implementing your own solution (basic rule in security: don't implement your own stuff!), but use the de-facto standard solution, namely JSON Web Tokens.
Documentation on the site, but the basic idea is, that you only need to store one value (the server's private key), and then you can verify every claim, issued originally by the server (which will in your case contain an expiry time).

You should use JsonWebToken (JWT in short) for this kind of stuff. JWT has build in support to set the expiration date. There are plenty of libraries to use this method and you can read more here
There are currenlty 4 java implementations and all of them can check if the token is still valid (exp check)

So if I'm understanding correctly you are using the same token for all of your requests (which means as long as your app is up and running and you refreshing the tokens, you should be ok. I literally had the same problem and this is how I've resolved it. I have a singleton class, which is initialized at the app start for once and refreshes the token when its invalidated. I'm using C#, Asp.NET MVC5 and AutoFac for DI, but I'm sure you can do the same with Java and Spring.
Updating property of a singleton with Thread Safety

Use json web tokens , to exchange information between two clients. The token will only alive for the 24 hours period, after that time all consequent calls in the header will be rejected.

Auth Token for each request is correct approach, Consider auth server scaling for performance issue.
On first successful authentication (username and password), generate private public keypair. Store private key as Session Security Token (SST) and send public key as Public Security Client Key (PSCK) to client
In all request other than login (or authentication) client will send PSCK to protect theft of username and password and server can verify PSCK for expiry internally at regular intervals saving processing time.
If system is having performance issue on authentication side, setup seperate auth server with scalability.
No token or password to be cached, exchanged unencrypted and send outside security zone. Do not post using URL parameters.

Best way to authenticate access token for every Rest API request

In general what is the best way to authenticate the access token in interceptors, If the access token information is stored in HashMap for each and every user, the hashmap grows as the number of users increases.
If we query database for every api request, it increases load on database.
Please mention if there are any other techniques you know.
And also what other things I need to consider while authenticating the access token for every request. What are the pre-processing and post-processing steps while authenticating access token.
Thanks in Advance.

Check out Json Web tokens. Using them allows your server to become stateless (not saving any sessions on memory).
Its concept is to pass a digital signed token, for every request, and checking that the signature is correct for integrity.
Json Web Encryption also can encrypt sensitive data along the token (such as user id).
This makes it very easy to work on a distributed environment
Check out this website: https://jwt.io/. There are some implementations in java and plenty of code examples to start with.

Some words about authentication with tokens
Once you are using JAX-RS, have a look at this answer that I wrote a while ago.
Your tokens can be any randon string persisted to some storage. On the other hand, JWT tokens allow you to have stateless authentication (no persistence). If you need to track the JWT tokens (to revoke them, for example), you must persist at least their identifier (the jti claim). A HashMap shouldn't be used to "persist" tokens (that's not a real persistence and it won't scale). Instead, consider a database like Redis.
To generate and parse JWT tokens, have a look this library created by Stormpath and maintained by a community of contributors. I currently use it in some applications and I can say with confidence that it works just fine and it's easy to use.
Keep reading for more details about the authentication process.
Authentication with tokens at a glance
In a few words, a token-based authentication follow these steps:
The client sends their credentials (username and password) to the server.
The server authenticates the credentials and generates a token.
The server stores the previously generated token in some storage along with the user identifier and an expiration date.
The server sends the generated token to the client.
In every request, the client sends the token to the server.
The server, in each request, extracts the token from the incoming request. With the token, the server looks up the user details to perform authentication and authorization.
If the token is valid, the server accepts the request.
If the token is invalid, the server refuses the request.
The server can provide an endpoint to refresh tokens.
Using JAX-RS to implement authentication based on tokens
The authentication starts when the server receives the hard credentials (username and password) of a user and exchanges them with a token that the client must send in each request:
#Path("/authentication")
public class AuthenticationResource {
#POST
#Produces(MediaType.APPLICATION_JSON)
#Consumes(MediaType.APPLICATION_JSON)
public Response authenticateUser(Credentials credentials) {
try {
// Authenticate the user using the credentials provided
String username = credentials.getUsername();
String password = credentials.getPassword();
authenticate(username, password);
// Issue a token for the user
String token = issueToken(username);
// Return the token on the response
return Response.ok(token).build();
} catch (Exception e) {
return Response.status(Response.Status.UNAUTHORIZED).build();
}
}
private void authenticate(String username, String password) throws Exception {
// Authenticate against a database, LDAP, file or whatever
// Throw an Exception if the credentials are invalid
}
private String issueToken(String username) {
// Issue a token (can be a random String persisted to a database or a JWT token)
// The issued token must be associated to a user
// Return the issued token
}
}
A filter will be used to extract the token from the HTTP request and validate it:
#Provider
#Priority(Priorities.AUTHENTICATION)
public class AuthenticationFilter implements ContainerRequestFilter {
#Override
public void filter(ContainerRequestContext requestContext) throws IOException {
// Get the HTTP Authorization header from the request
String authorizationHeader =
requestContext.getHeaderString(HttpHeaders.AUTHORIZATION);
// Check if the HTTP Authorization header is present and formatted correctly
if (authorizationHeader == null || !authorizationHeader.startsWith("Bearer ")) {
throw new NotAuthorizedException("Authorization header must be provided");
}
// Extract the token from the HTTP Authorization header
String token = authorizationHeader.substring("Bearer".length()).trim();
try {
// Validate the token
validateToken(token);
} catch (Exception e) {
requestContext.abortWith(
Response.status(Response.Status.UNAUTHORIZED).build());
}
}
private void validateToken(String token) throws Exception {
// Check if it was issued by the server and if it's not expired
// Throw an Exception if the token is invalid
}
}
For further details, have a look at this answer.
JSON Web Token
JSON Web Token (JWT) is defined by the RFC 7519 and I think it fits really well for your needs.
It's a standard method for representing claims securely between two parties (in this situation, client and server). JWT is a self-contained token and enables you to store a user identifier, an expiration date and whatever you want (but don't store passwords) in a payload, which is a JSON encoded as Base64.
The payload can be read by the client and the integrity of the token can be easily checked by verifying its signature on the server.
To find some great resources to work with JWT, have a look at http://jwt.io.
And remember: when sending sensitive data over the wire, your best friend is HTTPS. It protects your application against the man-in-the-middle attack.
Tracking the tokens
You won't need to persist JWT tokens if you don't need to track them.
Althought, by persisting the tokens, you will have the possibility of invalidating and revoking the access of them. To keep the track of JWT tokens, instead of persisting the whole token, you could persist the token identifier (the jti claim) and some metadata (the user you issued the token for, the expiration date, etc) if you need.
There are many databases where you can persist your tokens. Depending on your requirements, you can explore different solutions such as relational databases, key-value stores or document stores.
Your application can provide some functionality to revoke the tokens, but always consider revoking the tokens when the users change their password. When persisting tokens, always consider removing the old ones in order to prevent your database from growing indefinitely.

You can combine both HashMap and database. In your case, HashMap can be used as a cache. The first time user was authenticated, access token information of this user should store to HashMap. The next APIs, we will check if the access token is exist in HashMap. If it exists, we use it to authenticate, if not we will query from database and store it to HashMap.
You need to expire access tokens in HashMap that was not used for a duration.

Caching the access token on oauth or not?

I am currently implementing an authentication using oauth2 with Google.
I've read that I should cache the access token for later, but do I really need to do this?
I thought about storing it encrypted within the session. If it expires, I'll get a new token.
Also if I need to cache the token, how do I know to which user it belongs?

I've read that I should cache the access token for later, but do I
really need to do this?
Yes, that what is OAuth made for. The access token is needed to give your app access to a resource at the service provider without providing username and password every time.
I thought about storing it encrypted within the session. If it
expires, I'll get a new token.
It looks like you mixed up things here. The expiration of a session and of an access token are different things. The access token has usually a far longer life time then a session has (e.g. token: 60 minutes vs session: 15 minutes).
If an access token expires, you need the refresh token to get a new access token. If you don't have a refresh token, you have to initiate a grant flow again to get a new access token.
Also if I need to cache the token, how do I know to which user it
belongs?
That's your responsibility to maintain that connection in your DB somewhere. The service provider (in your case Google) does the same on their end, in order to match the access token to an user/resource. Regarding your 2nd point: you should also store the refresh token.
I suggest you have read here: Why is OAuth designed to have request token and access token?

You should definitely cache your access tokens. Generating access tokens is expensive, and usually they come with a relatively long expiration time, therefore they can be reused many times, avoiding bombarding the auth server with new requests every time.
As an example, here is a very simple implementation of a cache in Scala. A class implementing your oauth operations (getToken, refreshToken, etc.)
class authHandler private(serviceURL: java.net.URL) {
def getToken(clientId: String,
clientSecret: String,
scope: String,
resource: String = ""): Future[String] = {
val cacheKey = clientId + scope
S2SAuthHandler.getTokenFromCache(cacheKey) match {
case Some(tk) => Future(tk)
case None => requestTokenFromServer(clientId, clientSecret, scope, resource)
}
}
private def requestTokenFromServer(clientId: String,
clientSecret: String,
scope: String,
resource: String): Future[String] = {
val authToken = <http request from server>
//expiration time is set to a few seconds less than the one provided from the server, to avoid returning an already expired token.
authToken.expires = authToken.expires - 5 + System.currentTimeMillis() / 1000 S2SAuthHandler.storeTokenToCache(clientId + scope, authToken)
authToken.accessToken
}
}
and a companion object, implementing the cache. Companion objects in Scala are static, therefore you can create as many instances of your oauth handler class, still have one global cache available.
The cache is a simple map [key, token] where the key could be the "clientId + scope". You want to store different tokens per client and scope. The token should contain the access token per se, plus refresh token if available, expiration time, etc.
/** Companion objec */
object authHandler {
private val tokenCache = mutable.Map.empty[String, AuthToken]
private def getTokenFromCache(cacheKey: String): Option[String] = {
if ((tokenCache contains cacheKey) && (tokenCache(cacheKey).expires > System.currentTimeMillis / 1000)) {
Some(tokenCache(cacheKey).accessToken)
}
else {
None
}
}
private def storeTokenToCache(key: String, tk: AuthToken) = {
tokenCache(key) = tk
//Depending on your execution environment, I would recommend to encrypt the token before storing in the cache
}
}

Why Facebook Access Token Changed Each and Every Access?

We are using restFB 1.6.12. I am getting the facebook access token in two ways,
1. CLIENT_APP_ID = "XXXXXXXXXXXXXXXXXX";
CLIENT_SECRET = "XXXXXXXXXXXXXXXXXX";
REDIRECT_URL = "XXXXXXXXXXXXXXXXXX";
AUTH_CODE = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX";
SCOPE = "email,read_stream";
Redirect to facebook as the example. As a result I'll get an
authorization code
https://www.facebook.com/dialog/oauth?client_id=YOUR_APP_ID&redirect_uri=YOUR_URL&scope=email,read_stream
asking for an access_token using,
https://graph.facebook.com/oauth/access_token?client_id=YOUR_APP_ID&redirect_uri=YOUR_URL&client_secret=YOUR_APP_SECRET&code=THE_CODE_FROM_ABOVE
this returns the access token like this,
access_token=CAAHWfjdHDKcBAIL0zHMeJKzJw8Ug7WrrrkNxpBnK7ubnFR1RGtIIZA7T3UPlhCSV0hPJXZAgTcKfBSfHZAyxsndc3RT72XMREjACxnGb0ZCGMZAUgDWH3FgOhnaoSBMgkaQBPDOCCEKcLnznMYSncWS7dVxl9IFrSzeFjF6LKOWB3NTynl5X1&expires=5125218
2. AccessToken accessToken = new
DefaultFacebookClient().obtainAppAccessToken(appid,appsecret);
String token=accessToken.getAccessToken();
It reurns the access token like this,
access_token=517312558337191|5oHY9T3cZICO_TCeK8OdXKg5Y08
If I use the first(1) one, it works fine for first access after then every access throws an error
Auth Token= {"error":{"message":"This authorization code has been used.","type":"OAuthException","code":100}}
If I use the second(2) one, it works fine only for publicSearchMessages but when I access publicEvents or other searches it throws an error
com.restfb.exception.FacebookOAuthException: Received Facebook error response of type OAuthException: (#200) Must have a valid access_token to access this endpoint
at com.restfb.DefaultFacebookClient$DefaultGraphFacebookExceptionMapper.exceptionForTypeAndMessage(DefaultFacebookClient.java:766)
at com.restfb.DefaultFacebookClient.throwFacebookResponseStatusExceptionIfNecessary(DefaultFacebookClient.java:688)
at com.restfb.DefaultFacebookClient.makeRequestAndProcessResponse(DefaultFacebookClient.java:630)
at com.restfb.DefaultFacebookClient.makeRequest(DefaultFacebookClient.java:592)
at com.restfb.DefaultFacebookClient.makeRequest(DefaultFacebookClient.java:556)
at com.restfb.DefaultFacebookClient.fetchConnection(DefaultFacebookClient.java:219)
My question is, what is the difference between these two access token and how can I programmatically generate access code for first one to works publicSearchMessages, getPublicEvents and other searches?
Which one access token is used to works as expected?

Access_tokens allow users to interact with your apps in secure and social ways. While we are removing the use of the offline_access permission, through a migration setting in the App Dashboard, we are now allowing the option to use access_tokens with a long-lived expiration time that can be renewed each time the user revisits your app
When a user visits your site with an existing, valid, short-lived user access_token, you have the option to extend the expiration time of that access token.
extend the expiration time once per day, so even if a user revisits your site multiple times a day, the token will be extended the first time requested. You must make sure to call the new endpoint below before the short-lived access_token expires.
Using the new endpoint below, you will be able to extend the expiration time of an existing, non-expired, short-lived user access_token.
To get the long-lived user access_token simply pass your own client_id (your app_id), your app_secret, and the non-expired, short-lived access_token to the endpoint. You will be returned a new long-lived user access_token; this access_token will exist in addition to the short-lived access_token that was passed into the endpoint
In short Get a page access token – those don’t expire per default; and make sure to do so with a long-time user access token
You can access facebook doc here for more info
To get an extended Page Access Token, exchange the User Access Token for a long-lived one and then request the Page token. This "extended" token for Pages will actually not have any expiry time.
https://developers.facebook.com/docs/howtos/login/extending-tokens/#step1
resolve this by executing a curl request, and saving "Page access token" in your code manually