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.\" This definition swiped from the gcc(1) man page
.de Sp
.if n .sp
.if t .sp 0.4
..
.TH SMEM 1
.SH NAME
smem \- secure memory wiper (secure_deletion toolkit)
.SH SYNOPSIS
.B smem [-f] [-l] [-l] [-v]
.SH DESCRIPTION
.I smem
is designed to delete data which may lie still in your memory (RAM)
in a secure manner which can not be recovered by thiefs, law enforcement
or other threats.
Note that with the new SDRAMs, data will not wither away but will be kept
static - it is easy to extract the necessary information!
The wipe algorythm is based on the paper "Secure Deletion of Data from
Magnetic and Solid-State Memory" presented at the 6th Usenix Security
Symposium by Peter Gutmann, one of the leading civilian cryptographers.
.PP
The
.I secure data deletion
process of smem goes like this:
.PP
.TP
.B *
1 pass with 0x00
.TP
.B *
5 random passes. /dev/urandom is used for a secure RNG if available.
.TP
.B *
27 passes with special values defined by Peter Gutmann.
.TP
.B *
5 random passes. /dev/urandom is used for a secure RNG if available.
.PP
.SH COMMANDLINE OPTIONS
.PP
.TP
.B \-f
fast (and insecure mode): no /dev/urandom.
.TP
.B \-l
lessens the security. Only two passes are written: the first with 0x00
and a final random one.
.TP
.B \-l
-l for a second time lessons the security even more: only one pass with
0x00 is written.
.TP
.B \-v
verbose mode
.PP
.SH BEWARE
.TP
.B SLOW
Wiping the memory is very slow. You might use smem with the -ll option. (tip)
.TP
.B BETA!
.I smem
is still beta.
.PP
.SH BUGS
No bugs. There was never a bug in the secure_deletion package (in contrast
to my other tools, whew, good luck ;-)
Send me any that you find. Patches are nice too :)
.SH AUTHOR
.Sp
van Hauser / THC
.I <vh@thc.org>
.SH DISTRIBUTION
The newest version of the
.I secure_deletion package
can be obtained from
.I http://www.thc.org
.Sp
.I smem
and the
.I secure_deletion package
is (C) 1997-2003 by van Hauser / THC (vh@thc.org)
.Sp
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; Version 2.
.Sp
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
.SH SEE ALSO
.I srm
(1),
.I sfill
(1),
.I sswap
(1)
|
