man5/hosts.equiv.5

   1 .\" Copyright (c) 1995 Peter Tobias <tobias@et-inf.fho-emden.de>
   2 .\" This file may be distributed under the GNU General Public License.
   3 .TH HOSTS.EQUIV 5 2003-08-24 "Linux" "Linux Programmer's Manual"
   4 .SH NAME
   5 /etc/hosts.equiv \- list of hosts and users that are granted "trusted"
   6 \fBr\fP command access to your system
   7 .SH DESCRIPTION
   8 The \fBhosts.equiv\fP file allows or denies hosts and users to use
   9 the \fBr\fP-commands (e.g. \fBrlogin\fP, \fBrsh\fP or \fBrcp\fP) without
  10 supplying a password.
  11 .PP
  12 The file uses the following format:
  13 .TP
  14 \fI[ + | - ]\fP \fI[hostname]\fP \fI[username]\fP
  15 .PP
  16 The \fIhostname\fP is the name of a host which is logically equivalent
  17 to the local host. Users logged into that host are allowed to access
  18 like-named user accounts on the local host without supplying a password.
  19 The \fIhostname\fP may be (optionally) preceded by a plus (+) sign.
  20 If the plus sign is used alone it allows any host to access your system.
  21 You can expicitly deny access to a host by preceding the \fIhostname\fP
  22 by a minus (-) sign. Users from that host must always supply a password.
  23 For security reasons you should always use the FQDN of the hostname and
  24 not the short hostname.
  25 .PP
  26 The \fIusername\fP entry grants a specific user access to all user
  27 accounts (except root) without supplying a password. That means the
  28 user is NOT restricted to like-named accounts. The \fIusername\fP may
  29 be (optionally) preceded by a plus (+) sign. You can also explicitly
  30 deny access to a specific user by preceding the \fIusername\fP with
  31 a minus (-) sign. This says that the user is not trusted no matter
  32 what other entries for that host exist.
  33 .PP
  34 Netgroups can be specified by preceding the netgroup by an @ sign.
  35 .PP
  36 Be extremely careful when using the plus (+) sign. A simple typographical
  37 error could result in a standalone plus sign. A standalone plus sign is
  38 a wildcard character that means "any host"!
  39 .SH FILES
  40 .I /etc/hosts.equiv
  41 .SH NOTES
  42 Some systems will only honor the contents of this file when it has owner
  43 root and no write permission for anybody else. Some exceptionally
  44 paranoid systems even require that there be no other hard links to the file.
  45 .PP
  46 Modern systems use the Pluggable Authentication Modules library (PAM).
  47 With PAM a standalone plus sign is only considered a wildcard
  48 character which means "any host" when the word
  49 .I promiscuous
  50 is added to the auth component line in your PAM file for
  51 the particular service
  52 .RB "(e.g. " rlogin ).
  53 .SH "SEE ALSO"
  54 .BR rhosts (5),
  55 .BR rlogind (8),
  56 .BR rshd (8)