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.\" Copyright (c) 2003 Joseph Koshy <jkoshy@freebsd.org>
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.\" $FreeBSD$
.Dd November 11, 2003
.Os
.Dt cr_seeotheruids 9
.Sh NAME
.Nm cr_seeotheruids
.Nd determine visibility of objects given their user credentials
.Sh SYNOPSIS
.Ft int
.Fn cr_seeotheruids "struct ucred *u1" "struct ucred *u2"
.Sh DESCRIPTION
This function determines the visibility of objects in the
kernel based on the real user ids in the credentials
.Fa u1
and
.Fa u2
associated with them.
.Pp
The visibility of objects is influenced by the
.Xr sysctl 8
tunable
.Va security.bsd.see_other_uids .
If this tunable is non-zero, then all objects in the kernel
are visible to each other irrespective of their user ids.
If this tunable is zero, then the object with credentials
.Fa u2
is visible to the object with credentials
.Fa u1
if either
.Fa u1
is the super-user credential, or if
.Fa u1
and
.Fa u2
have the same real user id.
.Sh SYSCTL TUNABLES
.Bl -tag -width indent
.It Va security.bsd.see_other_uids
must be non-zero if objects with unprivileged credentials are to be
able to see each other.
.El
.Sh RETURN VALUES
This function returns zero if the object with credential
.Fa u1
can
.Dq see
the object with credential
.Fa u2 ,
or
.Er ESRCH
otherwise.
.Sh SEE ALSO
.Xr cr_seeothergids 9 ,
.Xr p_candebug 9