Subject: Re: Passing credentials as ancillary data
To: Jason Thorpe <>
From: Matt Thomas <>
List: tech-kern
Date: 01/07/1998 13:36:13
At 10:06 AM 1/7/98 -0800, Jason Thorpe wrote:
>On Wed, 07 Jan 1998 22:41:44 +1100 
> Luke Mewburn <> wrote:
> > > Yes the id's are all that the kernel check, but the login name can still be
> > > useful - for logging if nothing else.
> > 
> > yeah, i agree (where a setuid() has been done, but the logname is
> > still the original user).
>The reason the login name (and the supplemental group list, too) is not
>included is that you then change the format of the data structure if
>either MAXLOGNAME or NGROUPS is changed (there's also the problem of
>having to pull in <sys/param.h> to build socket-using code, but that's
>another issue :-).
>If you want to get the string identity of the original user, use getpwuid()
>with the real user id passed in the sockcred.

Or you could pass a self describing structure.  
uid/gid/euid/egid/grp-cnt/n-grps/loginname(0 term).

Matt Thomas               Internet:
3am Software Foundry      WWW URL:
Nashua, NH                Disclaimer: I disavow all knowledge of this message