Google+按钮后面的逆向工程Javascript

Question

I am trying to simulate google+ button.In Somepart of code at LINK ,It converts the session id into Some kinda hash.What i found is session id name is SAPISID and the converted hash name is SAPISIDHASH, Can anyone tell me which part of code does the hash part. Any help will be appreciated.i have spent 6 hours straight, still no clue:(

For Example VUOyLIU22fNPz2ko/AbGsxW03_WHoGjaJq is SAPISID and f17aa630b9b9a105dad437b0fedcafe429f6fca2 is SAPISIDHASH . In php i tried all kind of hash..nothing matches.

Answer 1

VICTORY. Well for me at least 😛 The SAPISIDHASH I was looking for was the one in the API console. Automation for rather large job, totally legitimate. The one I found was a SHA1 on the current JavaScript milliseconds timestamp plus your current SAPISID from your cookie plus the domain origin. In order for my request to work I had to include the following headers in the request:

Authorization:SAPISIDHASH 1439879298823_<hidden sha1 hash value>

and:

X-Origin:https://console.developers.google.com

The first header I assume tells the server your timestamp and your SHA1 value. The second (breaks if you don't include it) tells it the origin to use in the SHA1 algorithm. I found the algorithm by digging through and debugging the hell out of tons of minified JS NOTE there are spaces appended between the values . The psuedo code is basically:

sha1(new Date().getTime() + ' ' + SAPISID + ' ' + origin);

That is at least how I got my SAPISIDHASH value in my use case here in 2015 (few years later I know)... different from yours but maybe I will help some other young good hacker out there one day.

Answer 2

All credits to Dave Thomas.

I just want to clarify that for the X-Origin, or Origin, you do not include the "X-Origin:" or "Origin:"

Here is one example:

public class SAPISIDHASH {

    public static void main(String [] args) {

        String sapisid = "b4qUZKO4943exo9W/AmP2OAZLWGDwTsuh1";
        String origin = "https://hangouts.google.com";
        String sapisidhash = "1447033700279" + " " + sapisid + " " + origin;
        System.out.println("SAPISID:\n"+ hashString(sapisidhash));
        System.out.println("Expecting:");
        System.out.println("38cb670a2eaa2aca37edf07293150865121275cd");

    }

    private static String hashString(String password)
    {
        String sha1 = "";
        try
        {
            MessageDigest crypt = MessageDigest.getInstance("SHA-1");
            crypt.reset();
            crypt.update(password.getBytes("UTF-8"));
            sha1 = byteToHex(crypt.digest());
        }
        catch(NoSuchAlgorithmException e)
        {
            e.printStackTrace();
        }
        catch(UnsupportedEncodingException e)
        {
            e.printStackTrace();
        }
        return sha1;
    }

    private static String byteToHex(final byte[] hash)
    {
        Formatter formatter = new Formatter();
        for (byte b : hash)
        {
            formatter.format("%02x", b);
        }
        String result = formatter.toString();
        formatter.close();
        return result;
    }
}

source for sha1 in Java: Java String to SHA1