Getting Rid of Nasty Adobe Flash Cookies the Cool Linux Way - page 3
Using find to See What We're Up Against
Maybe you don't want the darned things on your system at all. As usual, Linux lets you control your own system and doesn't mind if you want to prevent Flash cookies from nesting on your system at all. There are a number of ways to do this. Flash cookies reside in two directories, ~/.macromedia/Flash_Player/#SharedObjects/ and ~/.macromedia/Flash_Player/macromedia.com/. If you want to see these in a graphical file manager, make sure you have "view hidden files" enabled. Delete all the files in these directories, then change the permissions to mode 0500, which is read-only and execute:
$ chmod -Rv 0500 .macromedia/Flash_Player/#SharedObjects/ .macromedia/Flash_Player/macromedia.com/support/flashplayer/sys/
mode of `.macromedia/Flash_Player/macromedia.com/support/flashplayer/sys/#blip.tv' changed to 0500 (r-x------)
mode of `.macromedia/Flash_Player/macromedia.com/support/flashplayer/sys/#cm.cdn.fm' changed to 0500 (r-x------)
chmod means "change read-write-execute mode", -R mean recursive (do the subdirectories), and v is verbose so you can see what is happening. That changes the #SharedObjects/ and sys/ directories and their sub-directories to read- and execute-only. You need these set so you can enter the directories to make sure no new cookies have been written. (Yes, this is how Unix directories work, they need the execute bit set so you can enter them.) But the directories are not writable so no new cookies can be added.
All of the commands in this article have good detailed man pages, plus you can find all kinds of tips and tricks online.
What About Gnash?
Rob Savoye, who is the main developer of Gnash (the Free Software Flash player), kindly wrote to me and shared some helpful information:
"Gnash supports LSOs too, but unlike Adobe, we print messages in a debug log (if it's enabled) about what is being stored. But more importantly, we do have a utility program called "soldumper" that one can use to dump all the encoded data in a .sol file to the terminal. This way you can see exactly what is being stored about you.
I've examined hundreds of .sol files when I was adding LSO support to Gnash, at at least so far, never found anything privacy oriented. Course anything can be stored, so I'm still paranoid. They're commonly full of config values more than anything else.
" And yes, Gnash plays much more attention to the users privacy and security than Adobe does. I think this is one area where free software is better than it's proprietary counterparts."
"Trust but verify" is a sound principle. I'm going to install Gnash and give it some serious testing, and perhaps even write up my experiences if I learn anything useful.
Thank you to the fine readers of Linux Today and LinuxPlanet for providing tips and inspiration for this article!
Carla Schroder is the author of the Linux Cookbook and the Linux Networking Cookbook (O'Reilly Media), the upcoming "Building a Digital Sound Studio with Audacity" (NoStarch Press), a lifelong book lover, and the managing editor of LinuxPlanet and Linux Today.