how to publish my app using Foursquare Secret? Security is concerned - api

I made a site using Foursquare API, and want to publish it on my personal homepage, but I have the security concern with my Foursquare SECRET.
I used ajax request in a JS file using the following format of URL, and I'm afraid clients would be able to read my Foursquare ID and Secret:
https://api.foursquare.com/v2/venues/search?client_id=CLIENT_ID&client_secret=CLIENT_SECRET&v=20180325&ll=lat,lng&query=cafe
I did search for a way to restrict accessible URL like Yelp does, but Foursquare doesn't seem to provide that method. What are the best way to secure my Foursquare Secret either/both on client-side or/and server-side? (I do not have much of a knowledge on back-end, but if a detailed information is provided, you'd be much appreciated, thank you all)

The easiest way would be to use the users token instead of your Client_ID / Client_Secret.
https://api.foursquare.com/v2/venues/search?oauth_token=someUsersToken&ll=lat,lng&query=cafe
Your app is linked to that token.
Another suggestion would be to use a server as a proxy. Send all request from your app to your server then have your server make the request to foursquare, injecting the client ID and secret, then send the foursquare response back to your app.
Problem I see with using the user token exposed is, they could potentially use that token to impersonate your app with requests to foursquare.
You can check here for more info on foursquare's authentication.
https://developer.foursquare.com/docs/api/configuration/authentication

Related

Is it a security vulnerability to put TWITTER_CONSUMER_KEY / SECRET in client for oAuth1 Twitter Login?

All of the React Native Twitter Login Clients that I'm finding seem to be hard-coding the TWITTER_CONSUMER_KEY and TWITTER_CONSUMER_SECRET into the the client code, rather than relying on a server to generate tokens and/or a twitter redirect URL.
Is this safe? (e.g. couldn't a consumer then DOS the API with the TWITTER_CONSUMER_KEY, causing the app to be rate limited?)
Is this the correct way to do it?
Is there a better / more secure way?
According to twitter's documentation, it seems like this is NOT the correct way to do this:
"In the event that you believe that your API keys has been exposed, you should regenerate your API keys by following these steps" - Authentication best practices
Examples which specify that the consumer key/secret should be hardcoded:
https://rnfirebase.io/docs/v5.x.x/auth/social-auth#Twitter
https://github.com/GoldenOwlAsia/react-native-twitter-signin/blob/master/Example/TwitterButton.js#L14
Related questions:
Twitter consumer secret really a secret?
Is it a security vulnerability
Yes.
Your app can be rate limited or flagged as malware/spam etc.
Is there a better / more secure way?
Basically only to have your own site auth (oauth2) done correctly and proxy specific requests from your clients, after validation or a simplified locked down site API that is then translated to the Twitter API.
Why is this, Twitter app-only auth supports OAuth2, allows a secure negotiated handshake and then requests made using a Bearer token. In this mode you can make requests on behalf of your App, but without a logged in user. So can't post tweets or see private accounts or read DMs.
For user-auth, Twitter only support OAuth1 and both the App and User are authenticated, but using a model that assumed plaintext http, so can't share a single token. Every single request needs to be made using consumer key/secret and signing the request. So there isn't a way to do this from a javascript client safely.
Is this safe?
Absolutely not. A bad actor can get users to authenticate via Twitter to receive their token credentials and then use your app's consumer key/secret (which would be available in plain text) to masquerade as your app to do all kinds of nasty stuff.
Is this the correct way to do it?
Given the security vulnerability described above, no.
Is there a better / more secure way?
I'm currently in the process of trying to figure out how to securely achieve authentication with Twitter. This involved a lot of reading, but it appears as though it's simply not possible without your own backend. I'll try and explain why:
Your goal is to receive the user's email/Twitter-ID
To achieve (1), you need to send a request to the GET account/verify_credentials endpoint (https://developer.twitter.com/en/docs/twitter-api/v1/accounts-and-users/manage-account-settings/api-reference/get-account-verify_credentials).
To do (2), you need to provide an authorisation header, which is constructed out of several items, including the user's OAuth tokens as well as your app's consumer key/secret. More info here: https://developer.twitter.com/en/docs/authentication/oauth-1-0a/authorizing-a-request.
You retrieve the user's OAuth tokens using the 3-legged OAuth flow
described here: https://developer.twitter.com/en/docs/authentication/oauth-1-0a/obtaining-user-access-tokens. The first step of this process is to send a POST request to the oauth/request_token endpoint (https://developer.twitter.com/en/docs/authentication/api-reference/request_token).
This endpoint itself requires an authorisation header constructed using
your app's consumer key/secret.
Obviously you can't perform step (4) because that implies you would have your consumer secret available in the client; even if it's not hardcoded, it would have to be in memory at runtime, at some point
Once you have your own backend service, one option would be for your client app to open a browser and direct to an endpoint (let's call it /auth/twitter) on this service which will perform all the steps mentioned above.
This same service could also implement another endpoint (/auth/twitter/token) which handles requests to the callback URL, which you set in your Twitter app settings. This callback URL is used as part of the same 3-legged flow. This endpoint would have all the information needed to then go ahead and retrieve the user's email/Twitter-ID.
Finally, /auth/twitter/token can redirect to a custom URL which your client app would need to handle as part of its URL schemes. It can include enough information by way of parameters for your app to continue as needed post-auth.

REST API authentication for web app and mobile app

I'm having some trouble deciding how to implement authentication for a RESTful API that will be secure for consumption by both a web app and a mobile app.
Firstly, I thought to investigate HTTP Basic Authentication over HTTPS as an option. It would work well for a mobile app, where the username and password could be stored in the OS keychain securely and couldn't be intercepted in transit since the request would be over HTTPS. It's also elegant for the API since it'll be completely stateless. The problem with this is for the web app. There won't be access to such a keychain for storing the username and password, so I would need to use a cookie or localStorage, but then I'm storing the user's private details in a readily accessible place.
After more research, I found a lot of talk about HMAC authentication. The problem I see with this approach is there needs to be a shared secret that only the client and server knows. How can I get this per-user secret to a particular user in the web app, unless I have an api/login endpoint which takes username/password and gives the secret back to store in a cookie? to use in future requests. This is introducing state to the API however.
To throw another spanner into the works, I'd like to be able to restrict the API to certain applications (or, to be able to block certain apps from using the API). I can't see how this would be possible with the web app being completely public.
I don't really want to implement OAuth. It's probably overkill for my needs.
I feel as though I might not be understanding HMAC fully, so I'd welcome an explanation and how I could implement it securely with a web app and a mobile app.
Update
I ended up using HTTP Basic Auth, however instead of providing the actual username and password every request, an endpoint was implemented to exchange the username and password for an access key which is then provided for every authenticated request. Eliminates the problem of storing the username and password in the browser, but of course you could still fish out the token if you had access to the machine and use it. In hindsight, I would probably have looked at OAuth further, but it's pretty complicated for beginners.
You should use OAuth2. Here is how:
1) Mobile App
The mobile app store client credentials as you state yourself. It then uses "Resource Owner Password Credentials Grant" (see https://www.rfc-editor.org/rfc/rfc6749#section-4.3) to send those credentials. In turn it gets a (bearer) token it can use in the following requests.
2) Web site
The website uses "Authorization Code Grant" (see https://www.rfc-editor.org/rfc/rfc6749#section-4.1):
Website sees unauthorized request and redirects browser to HTML-enabled autorization endpoint in the REST api.
User authenticates with REST service
REST site redirects user back to website with access token in URL.
Website calls REST site and swaps access token to authorization token.
Here after the website uses the authorization token for accessing the REST service (on behalf of the end-user) - usually by including the token as a "bearer" token in the HTTP Authorization header.
It is not rocket science but it does take some time to understand completely.
3) Restricting API access for certain applications
In OAuth2 each client is issued a client ID and client secret (here "client" is your mobile app or website). The client must send these credentials when authorizing. Your REST service can use this to validate the calling client
I resolved this for my own API quite easily and securely without the need to expose any client credentials.
I also split the problem into 2 parts. API authentication - is this a valid request from a recognised entity (website or native app). API authorisation, is that entity allowed to use this particular endpoint and HTTP verb.
Authorisation is coded into the API using an access control list and user permissions and settings that are set up within the API code, configuration and database as required. A simple if statement in the API can test for authorisation and return the appropriate response (not authorised or the results of processing the API call).
Authentication is now just about checking to see if the call is genuine. To do this I issue self signed certificates to clients. A call to the API is made from their server whenever they want - typically when they generate their first page (or when they are performing their own app login checks). This call uses the certificates I have previously provided. If on my side I am happy the certificate is valid I can return a nonce and a time limited generated API key. This key is used in all subsequent calls to other API endpoints, in the bearer header for example, and it can be stored quite openly in an HTML form field or javascript variable or a variable within an app.
The nonce will prevent replay attacks and the API key can be stolen if someone wants - they will not be able to continue using after it expires or if the nonce changes before they make the next call.
Each API response will contain the next nonce of if the nonce doesn't match it will return an authentication error. In fact of the nonce doesn't match I kill the API key too. This will then force a genuine API user to reauthenticate using the certificates.
As long as the end user keeps those certificates safe and doesn't expose the method they use to make the initial authentication call (like making it an ajax request that can be replayed) then the API's are nice and secure.
One way of addressing the issue of user authentication to the API is by requesting an authentication token from the API when the user logs in. This token can then be used for subsequent requests. You've already touched on this approach - it's pretty sound.
With respect to restricting certain web apps. You'll want to have each web app identify itself with each request and have this authentication carried out inside your API implementation. Pretty straight forward.

Is my solution good enough to ensure the requests to my API come from my own website/mobile?

I am building an API that is going to be used by a partner's website. The website will be in the same domain (api.example.com and www.example.com). In the future we might have a mobile app that will consume this API.
I would not like to have someone using my api for their own website/app. So I would like to have a way to validate my website to my API.
I've searched in SO and found out that I would have to set a Cookie in my website so I send it every ajax request. Fair enough, but how would I generate this cookie? If I call a method in my API, I would have to validate it's origin, so it wouldn't solve.
I could set an encryption key on both sides and encrypt some information with a salt and send to the api to check the information.
I am not a security expert, but it seems it would solve my issue. Is this correct?
When a user logs into my website, would it be safe to change this validation with the user's login token?
thanks!
What your describing is called a CSRF (Cross Site Forgery Request).
To prevent someone from accessing your API's from outside your request, your website should store a token within the session, pass this token for every API request, then the API should validate the token.
There is a ton of good articles on the subject, including many specific examples.
Here is one of them preventing-cross-site-request-forgeries

Should I trust an API that uses GET method for user auth?

I've been researching PASTEBIN type API's that would enable storage of code snippets for a project I'm working on. The problem is that most if the API's I've found do not support edit/update of existing pastes.
I found that the Snipt.org API does support snippet updates. However, authentication for the snipt.org API is done using your Twitter account. The snipt.org API docs (https://code.google.com/p/snipt-org/wiki/REST_API_Docs?tm=6#Authorization) suggest using a GET '/auth' call (providing a Twitter uname/password in the URL) to obtain an API token to access the API. Is it just me or does this seem like a good way to compromise your Twitter credentials?
I have used other sites that authenticate via Twitter, but I get authenticated on the Twitter site first which in turn sends a token to the authorized app.
Well, obviously this API has some serious flaws.
But if you use https, the URLs of GET requests will get encrypted along the way. (But still get logged in the cache of your browser. do clear it.)
So if you really like snipt, you could use a new twitter account created simply for the purpose of authenticating to snipt.
It won't feel particularly good. And I have some serious doubts about the rest of their security code based on this part of the API. But I do not see how exactly your credentials could be stolen using this part of it by others than the snipt maintainers who already have access to your snipts. So if you protect only snipts with the credentials, and no tweets, you should be alright.

Authentication for new Twitter API 1.1

I have an application that needs to display number of followers and following (users/show.json) for a random user on a public page (authentication is not required).
With the Twitter API 1.0 it was quite easy as authentication is not needed for the request. With the new Twitter API 1.1 is no more possible, so I need to authenticate the request (via OAuth).
Is it possible only "authenticate" the application and not the user too?
I mean: can I avoid to ask user to login and only authenticate with application key/secret? Or everytime I need to create a token with user credentials too, creating callback, etc.?
Yes, it is possible! If your application doesn't need to do things like post statuses or send direct messages on behalf of a user, you should be able to retrieve all of a user's public information with a single hardcoded set of Twitter OAuth credentials, and not require the user to authenticate.
Login to Twitter and go to the developer dashboard at https://dev.twitter.com/apps
Register a new application; after the application is registered, view the application details. You'll see an "OAuth Tool" tab, where you'll find all the relevant OAuth values for that application: Consumer Key, Consumer Secret, Access Token, and Access Token Secret.
Using these credentials, you'll be able to make requests to the new Twitter API.
If you're not comfortable using the Twitter API directly, there are a number of good API wrappers out there for various languages -- among others, the Temboo SDK, which will give you code snippets for calling various methods (and also gives you a place to securely store your Twitter credentials, so you don't need to bake them into your application).
Take a look at:
UserTimeline
GetFollowersByID
(Full disclosure: I work at Temboo.)
The easiest way to do what you're asking is to use Twitter API 1.1's 'application-only authentication' feature, which works for much of the API. See Application-only authentication. You can see a Python example of it in get_bearer_token.py.
Once you have a bearer token, you only need to include that in your request authorization header - signing is not necessary.