I made a small modification of libavformat that bruteforces the 4-byte code used in audible encrypted files. It automatically runs if an aax is passed (always encrypted) without the code provided. Previously, it would tell the user the code was needed and exit.
It takes between 5 and 10 minutes to crack it as currently implemented, upon which it performs the specified task (conversion, content extraction, etc) and outputs the decryption key on the console. Is there any interest in including this upstream? If it's a code quality issue, I'm open to suggestions, but if it's felt that this is outside the scope of the project or legally risky then I understand. I didn't do any kind of reverse engineering or anything legally gray as far as I know, just noticed that it's literally a 32-bit key after the fixed key is in place (which was already in ffmpeg code). I used a legally obtained aax from my own audible account to test it, even. The key it outputs is the same key you get from tools like audible-activator. It's basically a user ID for a login. I currently have a fork up on github here: https://github.com/FFmpeg/FFmpeg/compare/master...willrandship:master I'll generate a patch file if you're interested. Thanks, William Shipley _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
