Example: Generate oAuth v1 HMAC-SHA1 / HMAC-SHA256 signatures for Authorization header or GET
For a project I needed oAuth v1 "Authorization: OAuth ... "header signatures. Based on some open source I build a small DLL (32-bit) that can be used in LR to do the job. It supports Authorization header for POST and GET, but also can generate a GET request with OAuth parameters.
In the attached LR script you will find the DLL with headers and some sample code.
Note that you have to capture of know the consumer_key and consumer_secret. In one situation these were mangled in JS code, but making a memory dump of the browser revealed the unmangled data.