1.\" $NetBSD: fsirand.8,v 1.3 1998/06/08 12:41:43 lukem Exp $ 2.\" 3.\" Copyright (c) 1997 Christos Zoulas 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.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by Christos Zoulas. 17.\" 4. The name of the author may not be used to endorse or promote products 18.\" derived from this software without specific prior written permission 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 22.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 23.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 24.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 25.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 29.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30.\" 31.Dd March 7, 1997 32.Dt FSIRAND 8 33.Os 34.Sh NAME 35.Nm fsirand 36.Nd install random inode generation numbers in a filesystem 37.Sh SYNOPSIS 38.Nm 39.Op Fl x Ar constant 40.Op Fl p 41.Ar special 42.Sh DESCRIPTION 43.Nm 44writes random inode generation numbers for all the inodes on device 45.Ar special . 46These random numbers make the NFS filehandles less predictable, increasing 47security of exported filesystems. 48.Pp 49.Nm 50should be run on a clean and unmounted filesystem. 51.Pp 52The options are as follows: 53.Bl -tag -width indent 54.It Fl x Ar constant 55Exclusive-or the given constant with the random number used in the generation 56process. 57.It Fl p 58Print the current inode generation numbers; the filesystem is not modified. 59.El 60.Pp 61.Nm 62exits zero on success, non-zero on failure. 63.Sh SEE ALSO 64.Xr fsck_ffs 8 , 65.Xr newfs 8 66.Sh SECURITY CONSIDERATIONS 67The current implementation does not use a good random number generator, 68so the randomization can be predicted. 69