How can I check what csrf token is my rails controller expecting? - ajax

My production server is not able to verify the csrf token.
I have added the tag for csrf in the application layout and sending it through headers.
In my request call I can see the token is included.
However my rails app is not able verify it.
Is there any way I can check what csrf token is my controller is expecting?

This is part of the code used in ActionController to check for authenticity
form_authenticity_token == params[request_forgery_protection_token]
form_authenticity_token will give you the token your controller is expecting.
Refer to the source code here

Related

Regarding Cross site Scripting Forgery

I am working on csrf and using spring 5. Spring 5 automatically provide supports for csrf and on enabling csrf protection on the server side I am getting
403: Invalid X-CSRF token
So this means a token needs to come from frontend?
My understanding is that backend generates csrf token and sends as a response to frontend browser and then it uses this token and send it as cookies to the backend server and then backend will validate it. is my understanding is correct?
when manually generating the hidden token for csrf, How backend will know it is a valid csrf token?
Second Scenario: Suppose two users are logged in to my website and frontend is sending this token to backend then how the application will differentiate which token is for which user?
Also please explain how it works internally means we enabled csrf protection in the backend and manually generated a token on the front end then what it does behind the scenes?
consider my frontend is JS pages
Is there is any specialty of Spring 5 which take care's of sessions for each user and validate tokens automagically for each user?. I tried finding it on the official website but didn't get it anywhere
Hi Zaib the csrf token is generated from back-end as you stated, once it is generated is automatically sent to the front-end which must take care to retrieve from the model and re-post for each "POST" requests.
You can share the csrf token via different way mostly i used header or html parameter.
A token is related to a specific session so is not really important if you have a logged user or not , even not authenticated users must send the csrf token for "POST".
The csrf token is validated via a filter placed in the front of the filter chain defined by Spring security itself, if you search in the documentation there is a table showing you the position of each "default" filter enabled by Spring security. Moreover if you enable debug on Spring ( </debug> is enough in your xml configuration) you will have printed all the filters used while processing an http request.
So each time a request with "POST" method pass through that filter , it will check if in the parameters there is the csrf token or header.
I never used as cookie so it may a different case for you if specifically need that but it does not differ on how it works.
Here is the details of csrf implementation on Spring:
https://docs.spring.io/spring-security/site/docs/5.0.7.RELEASE/reference/htmlsingle/#csrf-configure
I said "POST" method but actually the token is checked for any method that is related to a change of state , you can refer to doc here:
https://docs.spring.io/spring-security/site/docs/4.2.5.RELEASE/apidocs/org/springframework/security/web/csrf/CsrfFilter.html
Hope this help clarifying a bit the usage of the csrf token.

How to use generated token from passport Laravel oAuth

Can someone assist me here, i have succeeded in setting up my passport on laravel 5.4 everything seems to work perfected. My question is once token is generated, am i supposed to save it for subsequent usage? i am just confused on the workflow. I am using password grant. I want to know how to pass token to another route that is making another call to another endpoint once token has been generated.
You append the token generated for each and every subsequent request that needs to be authenticated.In this case attach to the Authorization header of the request. Something like this:
Bearer eJ0eXAiOi.......

How do I send spring csrf token from Postman rest client?

I have csrf protection in spring framework. So in each request I send csrf token in header from ajax call, which is perfectly working.
<meta name="_csrf" content="${_csrf.token}"/>
<meta name="_csrf_header" content="${_csrf.headerName}"/>
var token = $("meta[name='_csrf']").attr("content");
var header = $("meta[name='_csrf_header']").attr("content");
In ajax
beforeSend: function(xhr) {
xhr.setRequestHeader(header, token),
xhr.setRequestHeader("username", "xxxx1"),
xhr.setRequestHeader("password", "password")
}
I haven't any idea to generate csrf token and include in header section of Postman Rest Client ? Would you please help me to send csrf token from Postman Rest Client?
The Easiest way to do this consistently so you don't have to get the token each time:
NOTE:you need to install PostMan Interceptor and activate it to have access to the browsers cookies
Create a new environment so environment variables can be stored
Create a login method with a test to store the XSRF cookie in an environment variable, in the test tab post this code
//Replace XSFR-TOKEN with your cookie name
var xsrfCookie = postman.getResponseCookie("XSRF-TOKEN");
postman.setEnvironmentVariable("xsrf-token", xsrfCookie.value);
EDIT
For anyone using the 5.5.2 postman or later you will also have to decode the cookie, and they have also provided alternative ways to obtain cookies as #Sacapuces points out
pm.environment.set("xsrf-token", decodeURIComponent(pm.cookies.get("XSRF-TOKEN")))
Now you will have an environment variable with xsrf-token in it.
Save your login method
Create the new post you want to create and in the headers add your XSRF-Token-Header Key, and the environment variable in handle bars to access it{{}}
Now before running your new request make sure you run your login, it will store the environment variable, and then when you run the actually request it will automatically append it.
I am able to send REST with csrf token by following the steps below:
The CSRF token generated automatically by spring security when you logged in. It will be shown at the response header.
The CSRF token can be used on subsequent request by setting X-CSRF-TOKEN with CSRF token on header.
Firstly you need to install PostMan Interceptor and activate it to have access to the browsers cookies.
You have to fetch the CSRF Token by making a GET Request:
Header: "XSRF-TOKEN" and Value: "Fetch"
You should see the Token in the cookie tab and can copy it (Notice: You can configure spring how the cookie should be named. Maybe your cookie has another name than "XSRF-TOKEN". Attention: You have the remove this blank char in the token from the newline)
Now make your POST Request and set the header to: Header: "X-XSRF-TOKEN" and Value: "Your copied Token without blanks"
For me works variant with adding X-CSRF-TOKEN to headers.
Please put X-CSRF-Token as key and FETCH as the value in the GET request header and you will receive the token in the response header
If you don't want to configure environment variables etc. here is the quickest solution
https://stackoverflow.com/a/49249850/3705478
I've used csrfTokenRepository() to allow spring security to generate csrf token
#EnableWebSecurity
public class AppSecurityConfig extends WebSecurityConfigurerAdapter{
#Override
protected void configure(HttpSecurity http) throws Exception {
// TODO Auto-generated method stub
http.csrf().csrfTokenRepository(CookieCsrfTokenRepository.withHttpOnlyFalse());
// your code
}
}
After adding these lines of code, use GET request to generate csrf token. I've used postman and I got token in the response cookies section. Copy the token and use it in POST call.
Official documentation link :
https://docs.spring.io/spring-security/site/docs/5.0.x/reference/html/csrf.html

Missing CSRF token in REST request

I'm writing a REST API using Spring MVC. I'm trying to access a controller method via a POST request.
I always receive a 403error:
Invalid CSRF Token '' was found on the request parameter '_csrf' or header 'X-CSRF-TOKEN'.
How can I deliver a CSRF token within my REST request?
I tried to use the default security password which is displayed during application startup as the value for _csrf but it wasn't successful.
How can I retrieve the CSRF token and is it correct to send the token in the _csrf parameter?
You will need to provide the correct header and CSRF token when making the request e.g.
request.setRequestHeader('${_csrf.headerName}', '${_csrf.token}');
You can also send the token as a request parameter using _csrf.parameterName.

WARNING: Can't verify CSRF token authenticity in case of API development

I am right now developing web APIs with Ruby on Rails. When the Rails app receives POST request without any csrf token, the following error message shall happen. Because the app has no views.
WARNING: Can't verify CSRF token authenticity
So my question is how can I escape csrf token check safely in this case?
Thank you very much in advance.
You can do this by adding
skip_before_filter :verify_authenticity_token
to your controller. This way all incoming requests to the controller skips the :verify_authenticity_token filter.
For rails 4 it should be
skip_before_action :verify_authenticity_token, only: [:one_or_two_actions_here]
Note that you should avoid skipping verify_authenticity_token on all actions of your controller, instead use the option only to skip only where you have to. See the docs

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