JWT stands for JSON Web Token. Used for authentication as well as resource access.
Decoding and verifying signed JWT token
In the default WSO2 server, the signature of JWT token is generated using the primary keystore of the server, where the private key of wso2carbon.jks is used to sign it. Therefore when you need to verify the signature you need to use public certificate of wso2carbon.jks file.Sample Java code to validate the signature is available here - http://xacmlinfo.org/2015/03/19/validate-and-process-jwt-tokens-with-java/
Is token generation and authentication happening in a different webapp in wso2 IS ?
In WSO2 Identity server 5.0, the token generation is done via a RESTful web app hosted inside WSO2 IS. It is accessible via https://$host:9443/oauth2/token. You can call with any REST client. This blog post shows how retrieve access token via curl - http://blog.facilelogin.com/2012/08/testing-wso2-identity-server-oauth-20.html
The token validation is performed via a SOAP service, its not a web application.
The token validation is performed via a SOAP service, its not a web application.
How to generate custom tokens?
How custom JWT tokens can be generated is explained in here - http://wso2.com/library/articles/2014/12/customize-json-web-token-generation-with-wso2-api-manager-1.8.0/From where does the JWT reads user attributes?
User attributes for the JWT token is retrieved from the user store that is connected with APIM. If we take APIM scenario as an example user must be in the user store that APIM (Key Manager) is connected. If claims are stored in some other place (rather than in the user store, in some custom database table), then you need to write an extension point to retrieve claims. As mentioned in here [https://docs.wso2.com/display/AM180/Passing+Enduser+Attributes+to+the+Backend+Using+JWT], you can implement new "ClaimsRetrieverImplClass" for it.
Use cases:
There was a use case where the claims contained in SAML response needed to be used to enrich HTTP header at API invocation time.
Claims that are contained in SAML2 Assertion are not stored by default. Therefore, they can not be retrieved when JWT token is created. But we can create a new user in the user store and store these attributes based on the details in the SAML2 assertion. If claims are stored in the user store by creating new user, those attributes would be added in to the JWT token by default and any customization is not required here.
Optionally we can store them in a custom database table. To achieve this, you may need to customize the current SAML2 Bearer grant handler implementation as it does not store any attribute of the SAML2 Assertion. Details on customizing existing grant type can be found here [http://xacmlinfo.org/2015/01/20/custom-grant-type-with-oauth/].
