I'm not talking about showing them a popup upon api key generation, where the user is specifically warned about the fact that
This is the only time you will see it. Make sure to save this to a safe place.
Instead, I'm talking about platforms, like RapidApi, where the ApiKey is automatically filled-in for each Api in the platform, whether the user is subscribed to an Api or not.
(example from RapidApi)
Putting aside the fact that on RapidApi you can even use just a single ApiKey for each subscribed Api, instead of generating a new and unique ApiKey for a specific Api, how do they do that?
If the frontend is able to fill automatically the X-RapidApi-Key field, (I suppose) it means that the frontend is asking their backend what is my ApiKey.
Also that means that the ApiKey itself could not be hashed in their databases, but at least it is encrypted and decrypted upon demand.
Alternatively it is just plain text in their database or I'm missing something.
On other API platforms, the ApiKey is exposed only upon generation and it is up to the user to save it and use it. Which is pretty much secure, but of course it's not that handy if a user is able to use multiple API/ApiKeys.
I have a simple web app that does the authentication of a user. It is working under https, as it is simple it requires two fields username, password + csrf token.
Now I have implemented a simple API, that verifies if the user with the given username and password exist. It is called with jquery.post() method, on the same domain, also using https, but I supply only username and password.
Assuming that my API has only one function for the moment "is-registered" do I need to worry about something? Except of course brute-force.
Assuming that my API has only one function for the moment "is-registered" do I need to worry about something?
"Something" is quite too broad for me to competently answer, but you do not need to worry about CSRF in your case, as long as you keep the request and its result and causes like you described. Let me tell you why.
CSRF attack means that an attacker tricks or forces an user to do an action (send request) which attacker wants with parameters and data an attacker wants, but in the name of the user (with user's valid session and/or other private information of the user).
You do not need CSRF tokens if it may never cause any harm to anyone if the website thinks that the user made the request, although he was just forced to do so. It seems like you case, because it does no harm if an user is forced to ask whether an account with name and password provided by attacker exists.
You just need to be careful not to change causes of such request and its result based on which user sent it.
I have an account that I do referrals on and instead of having to make an entire landing page, and provide users with my referral link - I'll just have them purchase from my account.
Is there any way I could generate a link that will automatically log users in without me having to reveal my password?
You could definitely do this by using something like a JSON Web Token (JWT).
Basically, the way it works is like this:
On your server, you create a JWT that is signed with a secret key (some random string that only your server knows).
In your JWT, you include your user's account ID that you want the purchase to come from.
You email this JWT to the person in a link, something like https://mywebsite.com/order?token=<jwt-token-here>.
The user clicks that link.
Your web server takes the token out of the URL parameters, and ensures it is valid (that the signature is good).
Your web server then finds the account ID in the token, and retrieves that user account from your user database.
You then LOG that user in using cookies or whatever, and direct them to the purchase page fully logged in!
This is a pretty typical web flow for what you're trying to do, and is a totally fine way to do things like this. There are tons of JWT libraries out there that make this easy to do, so it shouldn't be very technically challenging.
The only other thing you should know in regards to creating JWTs, is that you can set an 'expiration' time. You should DEFINITELY do this, as you don't want someone to be able to log in using your token months in the future. The best way to do it would to likely be generate a token that lasts for 24 hours or so, then email THAT to the user. This way, it expires after one day.
Last thing to know: there are actually quite a few auth libraries that simplify this stuff. I'm the author of one, myself: express-stormpath. Depending on what you're trying to do, that might actually make your life wayyy easier as it can generate those tokens automatically, and handle session creations for ya.
Hope that helps!
I know this is not the first time the topic is treated in StackOverflow, however, I have some questions I couldn't find an answer to or other questions have opposed answers.
I am doing a rather simple REST API (Silex-PHP) to be consumed initially by just one SPA (backbone app). I don't want to comment all the several authentication methods in this question as that topic is already fully covered on SO. I'll basically create a token for each user, and this token will be attached in every request that requires authentication by the SPA. All the SPA-Server transactions will run under HTTPS. For now, my decision is that the token doesn't expire. Tokens that expire/tokens per session are not complying with the statelessness of REST, right? I understand there's a lot of room for security improvement but that's my scope for now.
I have a model for Tokens, and thus a table in the database for tokens with a FK to user_id. By this I mean the token is not part of my user model.
REGISTER
I have a POST /users (requires no authentication) that creates a user in the database and returns the new user. This complies with the one request one resource rule. However, this brings me certain doubts:
My idea is that at the time to create a new user, create a new token for the user, to immediately return it with the Response, and thus, improving the UX. The user will immediately be able to start using the web app. However, returning the token for such response would break the rule of returning just the resource. Should I instead make two requests together? One to create the user and one to retrieve the token without the user needing to reenter credentials?
If I decided to return the token together with the user, then I believe POST /users would be confusing for the API consumer, and then something like POST /auth/register appears. Once more, I dislike this idea because involves a verb. I really like the simplicity offered in this answer. But then again, I'd need to do two requests together, a POST /users and a POST /tokens. How wrong is it to do two requests together and also, how would I exactly send the relevant information for the token to be attached to a certain user if both requests are sent together?
For now my flow works like follows:
1. Register form makes a POST /users request
2. Server creates a new user and a new token, returns both in the response (break REST rule)
3. Client now attaches token to every Request that needs Authorization
The token never expires, preserving REST statelessness.
EMAIL VALIDATION
Most of the current webapps require email validation without breaking the UX for the users, i.e the users can immediately use the webapp after registering. On the other side, if I return the token with the register request as suggested above, users will immediately have access to every resource without validating emails.
Normally I'd go for the following workflow:
1. Register form sends POST /users request.
2. Server creates a new user with validated_email set to false and stores an email_validation_token. Additionally, the server sends an email generating an URL that contains the email_validation_token.
3. The user clicks on the URL that makes a request: For example POST /users/email_validation/{email_validation_token}
4. Server validates email, sets validated_email to true, generates a token and returns it in the response, redirecting the user to his home page at the same time.
This looks overcomplicated and totally ruins the UX. How'd you go about it?
LOGIN
This is quite simple, for now I am doing it this way so please correct me if wrong:
1. User fills a log in form which makes a request to POST /login sending Basic Auth credentials.
2. Server checks Basic Auth credentials and returns token for the given user.
3. Web app attached the given token to every future request.
login is a verb and thus breaks a REST rule, everyone seems to agree on doing it this way though.
LOGOUT
Why does everyone seem to need a /auth/logout endpoint? From my point of view clicking on "logout" in the web app should basically remove the token from the application and not send it in further requests. The server plays no role in this.
As it is possible that the token is kept in localStorage to prevent losing the token on a possible page refresh, logout would also imply removing the token from the localStorage. But still, this doesn't affect the server. I understand people who need to have a POST /logout are basically working with session tokens, which again break the statelessness of REST.
REMEMBER ME
I understand the remember me basically refers to saving the returned token to the localStorage or not in my case. Is this right?
If you'd recommend any further reading on this topic I'd very much appreciate it. Thanks!
REGISTER
Tokens that expire/tokens per session are not complying with the statelessness of REST, right?
No, there's nothing wrong with that. Many HTTP authentication schemes do have expiring tokens. OAuth2 is super popular for REST services, and many OAuth2 implementations force the client to refresh the access token from time to time.
My idea is that at the time to create a new user, create a new token for the user, to immediately return it with the Response, and thus, improving the UX. The user will immediately be able to start using the web app. However, returning the token for such response would break the rule of returning just the resource. Should I instead make two requests together? One to create the user and one to retrieve the token without the user needing to reenter credentials?
Typically, if you create a new resource following REST best practices, you don't return something in response to a POST like this. Doing this would make the call more RPC-like, so I would agree with you here... it's not perfectly RESTful. I'll offer two solutions to this:
Ignore this, break the best practices. Maybe it's for the best in this case, and making exceptions if they make a lot more sense is sometimes the best thing to do (after careful consideration).
If you want be more RESTful, I'll offer an alternative.
Lets assume you want to use OAuth2 (not a bad idea!). The OAuth2 API is not really RESTful for a number of reasons. I'm my mind it is still better to use a well-defined authentication API, over rolling your own for the sake of being RESTful.
That still leaves you with the problem of creating a user on your API, and in response to this (POST) call, returning a secret which can be used as an access/refresh token.
My alternative is as follows:
You don't need to have a user in order to start a session.
What you can do instead is start the session before you create the user. This guarantees that for any future call, you know you are talking to the same client.
If you start your OAuth2 process and receive your access/refresh token, you can simply do an authenticated POST request on /users. What this means is that your system needs to be aware of 2 types of authenticated users:
Users that logged in with a username/password (`grant_type = passsword1).
Users that logged in 'anonymously' and intend to create a user after the fact. (grant_type = client_credentials).
Once the user is created, you can assign your previously anonymous session with the newly created user entity, thus you don't need to do any access/refresh token exchanges after creation.
EMAIL VALIDATION
Both your suggestions to either:
Prevent the user from using the application until email validation is completed.
Allow the user to use the application immediately
Are done by applications. Which one is more appropriate really depends on your application and what's best for you. Is there any risk associated with a user starting to use an account with an email they don't own? If no, then maybe it's fine to allow the user in right away.
Here's an example where you don't want to do this: Say if the email address is used by other members of your system to add a user as a friend, the email address is a type of identity. If you don't force users to validate their emails, it means I can act on behalf of someone with a different email address. This is similar to being able to receive invitations, etc. Is this an attack vector? Then you might want to consider blocking the user from using the application until the email is validated.
You might also consider only blocking certain features in your application for which the email address might be sensitive. In the previous example, you could prevent people from seeing invitations from other users until the email is validated.
There's no right answer here, it just depends on how you intend to use the email address.
LOGIN
Please just use OAuth2. The flow you describe is already fairly close to how OAuth2 works. Take it one step further an actually use OAuth2. It's pretty great and once you get over the initial hurdle of understanding the protocol, you'll find that it's easier than you thought and fairly straightforward to just implement the bits you specifically need for your API.
Most of the PHP OAuth2 server implementations are not great. They do too much and are somewhat hard to integrate with. Rolling your own is not that hard and you're already fairly close to building something similar.
LOGOUT
The two reasons you might want a logout endpoint are:
If you use cookie/session based authentication and want to tell the server to forget the session. It sounds like this is not an issue for you.
If you want to tell the server to expire the access/refresh token earlier. Yes, you can just remove them from localstorage, and that might be good enough. Forcing to expire them server-side might give you that little extra confidence. What if someone was able to MITM your browser and now has access to your tokens? I might want to quickly logout and expire all existing tokens. It's an edge case, and I personally have never done this, but that could be a reason why you would want it.
REMEMBER ME
Yea, implementing "remember me" with local storage sounds like a good idea.
I originally took the /LOGON and /LOGOUT approach. I'm starting to explore /PRESENCE. It seems it would help me combine both knowing someone's status and authentication.
0 = Offline
1 = Available
2 = Busy
Going from Offline to anything else should include initial validation (aka require username/password). You could use PATCH or PUT for this (depending how you see it).
You are right, SESSION is not allowed in REST, hence there is no need to login or logout in REST service and /login, /logout are not nouns.
For authentication you could use
Basic authentication over SSL
Digest authentication
OAuth 2
HMAC, etc.
I prefer to use PUBLIC KEY and PRIVATE KEY [HMAC]
Private key will never be transmitted over web and I don't care about public key. The public key will be used to make the user specific actions [Who is holding the api key]
Private key will be know by client app and the server. The private key will be used to create signature. You generate a signature token using private key and add the key into the header. The server will also generate the signature and validate the request for handshake.
Authorization: Token 9944b09199c62bcf9418ad846dd0e4bbdfc6ee4b
Now how you will get private key? you have to do it manually like you put facebook, twitter or google api key on you app.
However, in some case you can also return [not recommended] the key only for once like Amazon S3 does. They provide "AWS secret access key" at the registration response.
Many sites with registration that ask email confirmation and sites use tokens in their url.
Why do they use it?
For example in case of email confirmation: why just not use registered user id instead of token?! In case of using it in web pages, i didn't get at all!!
Explanation with real applications would be appreciated!
Thanks in advance!
A token in this context is typically a disposable time-limited random string used for verification. A token of (say) 40 characters can be generated easily [such as sha1(microtime() . rand(1, 10000)))], which isn't guessable by the user and isn't brute-forceable (within reason).
For email verification, a token will be generated and linked with your account ID. When you visit the address containing the token, the account gets activated. Since we've established that a token can't be brute-forced or guessed (within reason), we've just established that a certain user does indeed have the email address they gave us.
If we just used their member number, they could do several things to just guess it, thus bypassing the email check entirely.
When logging in or submitting a form of some kind, the term "token" may be used in a slightly different context - it's still a disposable time-limited random string, but it's used to make sure that the person who submitted the form has just come from the form they tried to submit.
For example, say you log into your online banking. They might have a form to transfer money to another bank account. If you go to www.nastysite.com they might include an iframe that points to <iframe src="http://www.mybank.com/send_money.php?amount=9001&to=Joe">. If your bank don't verify that you were actually on the form, that payment will go through, and you won't be best happy. Even if you are on the form, the chances of the correct token on your form being used in the fake page-load are (almost) nil.
This is called "Cross-Site Request Forgery", or CSRF. For some more reading on CSRF, have a look at this Wikipedia article. Also, I've just got that link after writing this post and seen that they use a very similar example to mine - genuine coincidence haha.