Re: Extended SCM_RIGHTS for AF_UNIX sockets

really (
19 Jul 1996 18:14:46 +0400

Malcolm Beattie ( wrote:

: We can now pass file descriptors down Unix domain sockets with
: an SCM_RIGHTS control messages in sendmsg() but can't easily
: tell for *certain* who sent them to us. [Guesses made via
: getpeername and stat are subject to minor attacks.] SysV file
: descriptor passing uses a STREAMS I_SENDFD and the receiver gets
: the sender's euid and egid. I'd like to add something like
: SCM_XRIGHTS to Linux which would behaves like SCM_RIGHTS on the
: sender side but the receiver gets a control message containing:
: uid_t uid;
: gid_t gid;
: pid_t pid;
: int fd[...];
: instead of just the array of descriptors. Notice that the trivial
: case is also useful. The sender can send zero file descriptors with
: SCM_RIGHTS and the receiver can verify who sent the message, both
: uid/gid and the PID of the sender. Would anyone mind if I added this
: extension?

Well, I already did similar thing (plus IP control messages).
Waiting for 2.1...

Alexey Kuznetsov.