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.\" opieaccess.5: Manual page describing the /etc/opieaccess file.
.\"
.\" Portions of this software are Copyright 1995 by Randall Atkinson and Dan
.\" McDonald, All Rights Reserved. All Rights under this copyright are assigned
.\" to the U.S. Naval Research Laboratory (NRL). The NRL Copyright Notice and
.\" License Agreement applies to this software.
.\"
.\" History:
.\"
.\" Modified by cmetz for OPIE 2.4. Fixed "0PIE" typo.
.\" Written at NRL for OPIE 2.0.
.\"
.ll 6i
.pl 10.5i
.\" @(#)opieaccess.5 2.0 (NRL) 1/10/95
.\" $FreeBSD$
.\"
.lt 6.0i
.TH OPIEACCESS 5 "January 10, 1995"
.AT 3
.SH NAME
/etc/opieaccess \- OPIE database of trusted networks
.SH DESCRIPTION
The
.I opieaccess
file contains a list of networks that are considered trusted by the system as
far as security against passive attacks is concerned. Users from networks so
trusted will be able to log in using OPIE responses, but not be required to
do so, while users from networks that are not trusted will always be required
to use OPIE responses (the default behavior). This trust allows a site to
have a more gentle migration to OPIE by allowing it to be non-mandatory for
"inside" networks while allowing users to choose whether they with to use OPIE
to protect their passwords or not.
.sp
The entire notion of trust implemented in the
.I opieaccess
file is a major security hole because it opens your system back up to the same
passive attacks that the OPIE system is designed to protect you against. The
.I opieaccess
support in this version of OPIE exists solely because we believe that it is
better to have it so that users who don't want their accounts broken into can
use OPIE than to have them prevented from doing so by users who don't want
to use OPIE. In any environment, it should be considered a transition tool and
not a permanent fixture. When it is not being used as a transition tool, a
version of OPIE that has been built without support for the
.I opieaccess
file should be built to prevent the possibility of an attacker using this file
as a means to circumvent the OPIE software.
.sp
The
.I opieaccess
file consists of lines containing three fields separated by spaces (tabs are
properly interpreted, but spaces should be used instead) as follows:
.PP
.nf
.ta \w' 'u
Field Description
action "permit" or "deny" non-OPIE logins
address Address of the network to match
mask Mask of the network to match
.fi
Subnets can be controlled by using the appropriate address and mask. Individual
hosts can be controlled by using the appropriate address and a mask of
255.255.255.255. If no rules are matched, the default is to deny non-OPIE
logins.
.SH SEE ALSO
.BR ftpd (8)
.BR login (1),
.BR opie (4),
.BR opiekeys (5),
.BR opiepasswd (1),
.BR opieinfo (1),
.BR su (1),
.SH AUTHOR
Bellcore's S/Key was written by Phil Karn, Neil M. Haller, and John S. Walden
of Bellcore. OPIE was created at NRL by Randall Atkinson, Dan McDonald, and
Craig Metz.
S/Key is a trademark of Bell Communications Research (Bellcore).
.SH CONTACT
OPIE is discussed on the Bellcore "S/Key Users" mailing list. To join,
send an email request to:
.sp
skey-users-request@thumper.bellcore.com
|
