CODEWITHSUNDEEP
javascript
dropWizard
dropWizard

Reputation: 3538

Accessing a Javascript variable inside an HTML file

I'm doing a little bit of reverse engineering on the Rapportive API in Gmail.

I make this request 

import requests
url ='https://api.linkedin.com/uas/js/xdrpc.html'
r = requests.get(url)
print r.text

The response is an empty HTML file that has a lot of Javascript in it. On line 3661, it sets the RequestHeader for the subsequent call to Rapportive: 

ak.setRequestHeader("oauth_token", ae);

Is there a way I can request that page and then return ae?

Upvotes: 5

Views: 211

Answers (2)

Felypp Oliveira
Felypp Oliveira

Reputation: 2187

I think you can try:

  1. Get the page as you already does;
  2. Remove all non-javascript elements from the response page;
  3. Prepend a javascript (described below) in the page's javascript to override some code;
  4. Execute it with eval('<code>');
  5. Check if the token has been set correctly;

I'm proposing the following code to override the XMLHttpRequest.setRequestHeader functionality to be able to get the token:

// this will keep the token
var headerToken; 

// create a backup method
XMLHttpRequest.prototype.setRequestHeaderBkp = 
XMLHttpRequest.prototype.setRequestHeader; 

// override the "setRequestHeader" method
XMLHttpRequest.prototype.setRequestHeader = function(key, val)
{
  if ('oauth_token' === key)
    headerToken = val;

  this.setRequestHeaderBkp(key, val);
}

Upvotes: 1

James Buck
James Buck

Reputation: 1640

If you are just interested in retrieving the token can't you just do a regex match:

var str = '<script>var a = 1;...ak.setRequestHeader("oauth_token", ae);...</script>';
var token = str.match(/setRequestHeader\("oauth_token",\s*([^)]+)/)[1];

Although this assumes ae is the actual string value. If it's a variable this approach wouldn't work as easily.

Edit: If it's a variable you could do something like:

str.replace(/\w+\.setRequestHeader\([^,]+,\s*([^)]+)\s*\);/, 'oauthToken = \1';

Before running the JavaScript returned from the page, then the global oauthToken (notice the missing 'var') will contain the value of the token, assuming the the evaluation of the code is run in the same scope as the caller.

Upvotes: 0

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