1.\" 2.\" Copyright (c) 2006 Ceri Davies <ceri@FreeBSD.org> 3.\" 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd November 19, 2006 29.Dt CR_CANSEE 9 30.Os 31.Sh NAME 32.Nm cr_cansee 33.Nd "determine visibility of objects given their user credentials" 34.Sh SYNOPSIS 35.In sys/param.h 36.In sys/systm.h 37.In sys/ucred.h 38.Ft int 39.Fn cr_cansee "struct ucred *u1" "struct ucred *u2" 40.Sh DESCRIPTION 41This function determines the visibility of objects in the 42kernel based on the real user IDs and group IDs in the credentials 43.Fa u1 44and 45.Fa u2 46associated with them. 47.Pp 48The visibility of objects is influenced by the 49.Xr sysctl 8 50variables 51.Va security.bsd.see_other_gids 52and 53.Va security.bsd.see_other_uids , 54as per the description in 55.Xr cr_seeothergids 9 56and 57.Xr cr_seeotheruids 9 58respectively. 59.Sh RETURN VALUES 60This function returns zero if the object with credential 61.Fa u1 62can 63.Dq see 64the object with credential 65.Fa u2 , 66or 67.Er ESRCH 68otherwise. 69.Sh ERRORS 70.Bl -tag -width Er 71.It Bq Er ESRCH 72The object with credential 73.Fa u1 74cannot 75.Dq see 76the object with credential 77.Fa u2 . 78.It Bq Er ESRCH 79The object with credential 80.Fa u1 81has been jailed and the object with credential 82.Fa u2 83does not belong to the same jail as 84.Fa u1 . 85.It Bq Er ESRCH 86The MAC subsystem denied visibility. 87.El 88.Sh SEE ALSO 89.Xr cr_seeothergids 9 , 90.Xr cr_seeotheruids 9 , 91.Xr mac 9 , 92.Xr p_cansee 9 93