WSO2 App Manager -Extract JWT token from wire log

App Manager provides SSO based on SAML for web apps published through it.So developers no need to worry about handling authentication in their web apps. They can develop unsecured web app and simply secure it via App Manager.

When a user try to access the unsecured web app though app manager(gateway component), authentication will be checked at gateway. If user is authenticated successfully he/she will be allowed to access the unsecured web app through gateway.

In some cases , unsecured web app may need the information of authenticated user to provide data/details related authenticated user.In such scenarios gateway should send the authenticated user information securely to the back end. Gateway is capable to send authenticated user’s information to back end app using JWT[1].  Configuring App Manager for JWT support can be found here[2].

In this post I am going to discuss on how to

1. Extract the encoded JWT token which is sent to back end web app by App Manager gateway.

2. Decode and verify the signature of the extracted token.

1. Extract the encoded JWT token

By default encoded JWT token is attached to “X-JWT-Assertion” http header. You can change the header where JWT token should be attached by configuring
<SecurityContextHeader/>  element in app-manger.xml[2].

By enabling the wire log in gateway ,  can find all the messages coming in to gateway and going out from gateway. So encoded JWT token can be extracted from the messages which going out from gateway to back end application.

1. Enable wire log
a. Open 
open file from <APPM_HOME>/repository/config
b. Un-comment the following entry.

2. Invoke the web app through gateway

3. Extract the message with http header X-JWT-Assertion

[2016-02-22 11:19:50,709] DEBUG – wire << “X-JWT-Assertion: eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsIng1dCI6Ik5rSkdPRVV4TXpaRlFqTTJSRFJCTlRaRlFUQTFRemRCUlRSQ09VRTBOVUkyTTBKR09UYzFSQT09In0=.eyJpc3MiOiJ3c28yLm9yZy9wcm9kdWN0cy9hcHBtIiwiZXhwIjoxNDU2MTIwOTE0NDM2LCJzdWIiOiJhZG1pbkBjYXJib24uc3VwZXIiLCJodHRwOi8vd3NvMi5vcmcvY2xhaW1zL3JvbGUiOiJJbnRlcm5hbC9hcHAxLXNpdGUtMSxJbnRlcm5hbC9hcHAxLXdlYi0xLEludGVybmFsL3B1Ymxpc2hlcixJbnRlcm5hbC9qd3QtMSxJbnRlcm5hbC9QbGFuWW91clRyaXBfYWRtaW4tMS4wLjAsSW50ZXJuYWwvYW5vbjEtc2l0ZS0xLEludGVybmFsL2NyZWF0b3IsYWRtaW4sSW50ZXJuYWwvcm9sZS13ZWJhcHAtMSxJbnRlcm5hbC9zdWJzY3JpYmVyLEludGVybmFsL3N0b3JlLWFkbWluLEludGVybmFsL2V2ZXJ5b25lLEludGVybmFsL2Fub24xLXdlYmFwcC0xIn0=.D17S22rLu+jjqEXrcqK9CnZuUGrIOVT7zPoUIq+AsnQTSqyUsvsR7CSvLK23w5hNrRapTgRdoCem2OxMLd3eLXZQN1mnMI4rzh+yYst8WhssPYC+RgedXf/J79PWTitg1ZJf/dogwUTx81YB7/gXlh8Tp34qf0djxVcwbpL/THA=[\r][\n]”

4. Extract the encoded JWT token(which is in bold text) from above message
Encoded token

2. Decode and verify the signature of the extracted token
Here we are not going to focus on how to decode the token in detail. Instead we are going to user the to decode the token and and verify the signature.

1. Copy the extracted token and paste to debugger tool.
It will decode the token and display the header and payload of the token.but as you can see in the image signature is not verified.

2. Verify the signature.

By default app manager(gateway) sign the jwt token with RS256 algorithm. This information should be available in the jwt token header(“alg”: “RS256”,) .  You can find more on signature configuration here[2].

To verify the signature in for RS256, we need to provided the certificate of gateway .

This is the default public key of carbon server.


Copy and paste the above key  to text box which require public key in debugger. Now as you can see in the image signature is verified



How to use mobile store in WSO2 APPManager without MDM

WSO2 APP Manager 1.0.0 has  feature to manage the mobiles apps. It supports to manage mobile apps under 3 categories.

  1. android apps
  2. iOS apps
  3. web apps

Steps to create  different mobile apps can be found in doc[1]

Once apps are created life cycle of apps can be managed as mentioned in the doc[2] . Apps which have life cycle status Published will appear in the store of app manager.

When select the “Mobile application” menu in the store, by default it will show all published mobile apps(image 1). if you want to browse only particular category e.g android apps. you can filter it by selecting the category in the drop down menu(image 2).



image 1


image 2


Configure App Manager to Enable mobile app to download directly to the mobile device from the App Manager without MDM

  1. Stop the app manager server if it is running.
  2. Open app-manager.xml which can be found under APPMANAGER_HOME>/repository/conf directory.
  3. Find the element  <Config name=”EnableDirectDownload”> under <MDMConfig> and set its value as true .
    <Config name=”EnableDirectDownload”>true</Config>
  4. Start the app manager server


Now go to the store via mobile device and select the published mobile app,which will take you to the overview section of the mobile app. There you can find “install” button(image 3) ,which will let you to download the mobile app to your mobile device. Once downloaded you can install it in you device.

mobileapp-isntall image 3