Date: Mon, 25 Nov 1996 09:03:53 -0500 (EST) From: Bill Paul <wpaul@skynet.ctr.columbia.edu> To: j@uriah.heep.sax.de (J Wunsch) Cc: hackers@freebsd.org Subject: Re: looking for an idea Message-ID: <199611251403.JAA05764@skynet.ctr.columbia.edu> In-Reply-To: <199611250935.KAA16590@uriah.heep.sax.de> from "J Wunsch" at Nov 25, 96 10:35:28 am
next in thread | previous in thread | raw e-mail | index | archive | help
Of all the gin joints in all the towns in all the world, J Wunsch had to walk into mine and say: > As Bill Paul wrote: > > > Now, the problem is to find a way for A to verify B's UID without > > resorting to grovelling in /dev/kmem. This is necessary since A would > > need privileges to open /dev/kmem, and A and B might not be run by > > privileged users. > > /proc/$pid/status is readable by everyone, and contains the real and > effective UID of the process. I'm sorry that's incorrect, but that's for playing. You didn't read the rest of my message, did you. I said that I'd already thought of using /proc; I also said that in order for that to work, I would need to know B's PID first (or am I supposed to just pull $pid out of thin air). Learning the PID of B is just as big a problem as learning the UID of B. Also, it doesn't work if, for some reason, PROCFS isn't configured in the kernel or /proc isn't mounted. -Bill -- ============================================================================= -Bill Paul (212) 854-6020 | System Manager, Master of Unix-Fu Work: wpaul@ctr.columbia.edu | Center for Telecommunications Research Home: wpaul@skynet.ctr.columbia.edu | Columbia University, New York City ============================================================================= "If you're ever in trouble, go to the CTR. Ask for Bill. He will help you." =============================================================================
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199611251403.JAA05764>