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.\" Copyright (c) 2003 Joseph Koshy <jkoshy@FreeBSD.org>
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.Dd August 18, 2023
.Dt PRISON_CHECK 9
.Os
.Sh NAME
.Nm prison_check
.Nd determine if subjects may see entities according to jail restrictions
.Sh SYNOPSIS
.In sys/jail.h
.Ft int
.Fn prison_check "struct ucred *cred1" "struct ucred *cred2"
.Sh DESCRIPTION
This function determines if a subject with credentials
.Fa cred1
is denied access to subjects or objects with credentials
.Fa cred2
according to the policy that a subject can see subjects or objects in its own
jail or any sub-jail of it.
.Sh RETURN VALUES
The
.Fn prison_check
function
returns
.Er ESRCH
if
.Fa cred2
is not in the same jail or a sub-jail of that of
.Fa cred1 .
In all other cases,
.Fn prison_check
returns zero.
.Sh SEE ALSO
.Xr jail 2