How Encrypted Binaries Work In Mac OS X

An anonymous reader writes "By now we know that OS X uses encrypted binaries for some critical apps like Dock, Finder and LoginWindow. Amit Singh explains the implementation of this protection scheme which makes use of the AES crypto algorithm and a special memory pager in Mach. The so called Do Not Steal Mac OS X (DSMOS) kernel extension helps along the way by decrypting things for the special pager when apps get executed. A funny thing is that if you print the pointer at address 0xFFFF1600 in your own app you get as output Apple's karma poem for crackers! According to the article there are 8 protected binaries in OSX including Rosetta and Spotlight meta data demon. Interestingly Apple's window server is NOT one of those."

Comments

It sure was simpler back in the day!

[KlaymenDK]

This is not the first "Do not steal Mac OS" they've done, although the first version never really got tested in action.

http://www.folklore.org/StoryView.py?project=Macin tosh&story=Stolen_From_Apple.txt&sortOrder=Sort%20 by%20Date&detail=medium&search=stolen

History repeating! :D

why bother?

[oohshiny]

It doesn't really matter what they protect, they are simply trying to make copying OS X wholesale more cumbersome. Functionally, there is nothing in OS X that would be worth disassembling for anybody: there are already open source implementations of Spotlight, Finder, SystemUIServer, Doc, and all the other stuff, and arguably, the open source versions are technically better. The thing that makes Macs shine and sell is the packaging and integration, not the technology.

Re:Love mac - hate some of the choices

[frdmfghtr]

I also can't stand spotlight. It is a resource hog and doesn't work well, plus it takes up critical real estate on the menu bar.

"Critical real estate on the menu bar"? Exactly how big is your Spotlight icon? Mine is less than half the size of my little fingernail on my 12" iBook, as big across as the menu bar is thick. I hardly call that "critical" but if that's your opinion, then so be it.