Edit: /usr/share/doc/pam/txts/README.pam_access (5253B)
pam_access -- PAM module for logdaemon style login access control
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DESCRIPTION
The pam_access PAM module is mainly for access management. It provides
logdaemon style login access control based on login names, host or domain
names, internet addresses or network numbers, or on terminal line names, X
$DISPLAY values, or PAM service names in case of non-networked logins.
By default rules for access management are taken from config file
/etc/security/access.conf if you don't specify another file. Then
individual *.conf files from the /etc/security/access.d/ directory are
read. The files are parsed one after another in the order of the system
locale. The effect of the individual files is the same as if all the files
were concatenated together in the order of parsing. This means that once a
pattern is matched in some file no further files are parsed. If a config
file is explicitly specified with the accessfile option the files in the
above directory are not parsed.
If Linux PAM is compiled with audit support the module will report when it
denies access based on origin (host, tty, etc.).
OPTIONS
accessfile=/path/to/access.conf
Indicate an alternative access.conf style configuration file to
override the default. This can be useful when different services
need different access lists.
debug
A lot of debug information is printed with syslog(3).
noaudit
Do not report logins from disallowed hosts and ttys to the audit
subsystem.
nodefgroup
User tokens which are not enclosed in parentheses will not be
matched against the group database. The backwards compatible
default is to try the group database match even for tokens not
enclosed in parentheses.
nodns
Do not try to resolve tokens as hostnames, only IPv4 and IPv6
addresses will be resolved. Which means to allow login from a
remote host, the IP addresses need to be specified in access.conf.
quiet_log
Do not log denials with syslog(3).
fieldsep=separators
This option modifies the field separator character that pam_access
will recognize when parsing the access configuration file. For
example: fieldsep=| will cause the default `:' character to be
treated as part of a field value and `|' becomes the field
separator. Doing this may be useful in conjunction with a system
that wants to use pam_access with X based applications, since the
PAM_TTY item is likely to be of the form "hostname:0" which
includes a `:' character in its value. But you should not need
this.
listsep=separators
This option modifies the list separator character that pam_access
will recognize when parsing the access configuration file. For
example: listsep=, will cause the default ` ' (space) and `\t'
(tab) characters to be treated as part of a list element value and
`,' becomes the only list element separator. Doing this may be
useful on a system with group information obtained from a Windows
domain, where the default built-in groups "Domain Users", "Domain
Admins" contain a space.
EXAMPLES
These are some example lines which might be specified in
/etc/security/access.conf.
User root should be allowed to get access via cron, X11 terminal :0, tty1,
..., tty5, tty6.
+:root:crond :0 tty1 tty2 tty3 tty4 tty5 tty6
User root should be allowed to get access from hosts which own the IPv4
addresses. This does not mean that the connection have to be a IPv4 one, a
IPv6 connection from a host with one of this IPv4 addresses does work,
too.
+:root:192.168.200.1 192.168.200.4 192.168.200.9
+:root:127.0.0.1
User root should get access from network 192.168.201. where the term will
be evaluated by string matching. But it might be better to use
network/netmask instead. The same meaning of 192.168.201. is
192.168.201.0/24 or 192.168.201.0/255.255.255.0.
+:root:192.168.201.
User root should be able to have access from hosts foo1.bar.org and
foo2.bar.org (uses string matching also).
+:root:foo1.bar.org foo2.bar.org
User root should be able to have access from domain foo.bar.org (uses
string matching also).
+:root:.foo.bar.org
User root should be denied to get access from all other sources.
-:root:ALL
User foo and members of netgroup admins should be allowed to get access
from all sources. This will only work if netgroup service is available.
+:@admins foo:ALL
User john and foo should get access from IPv6 host address.
+:john foo:2001:db8:0:101::1
User john should get access from IPv6 net/mask.
+:john:2001:db8:0:101::/64
Disallow console logins to all but the shutdown, sync and all other
accounts, which are a member of the wheel group.
-:ALL EXCEPT (wheel) shutdown sync:LOCAL
All other users should be denied to get access from all sources.
-:ALL:ALL