Subject: Re: Passing credentials as ancillary data
To: Ronald Khoo <>
From: Jason Thorpe <>
List: tech-kern
Date: 01/07/1998 18:52:59
On Thu, 8 Jan 1998 02:19:32 +0000 
 Ronald Khoo <> wrote:

 > Presumably it's for the same security/audit model reasons that
 > SecureWare C3 (e.g. SCO unix) implements the setluid() call.
 > It's supposed to be an audit identifier that *cannot* under any
 > circumstances be hidden.  The UID and EUID indicate whose
 > permissions are being used to authenticate whether or not something
 > may be done.  The login name indicates who actually initiated
 > the function, and should be preserved through inheritance
 > regardless of how many setuid-whoever programs or set*uid() calls
 > are made.

...not really... I mean, the login name can be changed with setlogin().

 > I'm guessing of course -- I'm no security weenie -- but there
 > seems little point in implementing a tiny part of an audit
 > infrastructure that we don't have, except for binary compatibility,
 > where we call always fill in the bsdos_ucred structure with the
 > constant string "root" :-)

Oh, it's easy to get that info, from the process's session... but the
point is that it's not really part of the process's _credentials_.

Jason R. Thorpe                             
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