= PAM Support for FreeRadius

PAM support was done by Jeph Blaize. Miguel a.l. Paraz
mailto:map@iphil.net[map@iphil.net] ported it to FreeRADIUS’
parent, Cistron-Radius. Chris Dent
mailto:cdent@kiva.net[cdent@kiva.net] added the Pam-Auth
attribute.

== Usage

Use Auth-Type = Pam in the users file. You cannot use
`User-Password = PAM` as in other radius servers. Sorry.

You can also use `Pam-Auth = somestring` to specify an entry in
/etc/pam.d. The default is `radius`.

Compile and install freeradius with pam support (./configure –help will
tell you how)

Within your radiusd.conf file, in the `modules' section, make sure that
the pam section is enabled:

```
 pam {
         #
         #  The name to use for PAM authentication.
         #  PAM looks in /etc/pam.d/${pam_auth_name}
         #  for it's configuration.
         #
         #  Note that any Pam-Auth attribute set in the 'users'
         #  file over-rides this one.
         #
         pam_auth = radiusd
 }
```

In the `authenticate` section, do the same:

```
process Access-Request { # Uncomment this if you want to use PAM
(Auth-Type = PAM) pam …
```

In your /etc/pam.d/ directory create a file called radiusd with the
following contents (or whatever you want for your pam configuration,
this seems to work for me):

```
#%PAM-1.0 auth required /lib/security/pam_unix_auth.so shadow md5 nullok
auth required /lib/security/pam_nologin.so account required
/lib/security/pam_unix_acct.so password required
/lib/security/pam_cracklib.so password required
/lib/security/pam_unix_passwd.so shadow md5 nullok use_authtok session
required /lib/security/pam_unix_session.so
```

If you don’t want to run your freeradius server in debug mode as root
(ie, run as an unpriviledged user) you will need to run freeradius with
a group membership that is able to read the /etc/shadow file - otherwise
pam will be unable to read the /etc/shadow file and will fail. I suggest
a group called `shadow' or the like.

```
$ chgrp /etc/shadow shadow
$ chmod g+w /etc/shadow
```

And in the radiusd.conf file:

```
# On systems with shadow passwords, you might have to set `group = shadow`
# for the server to be able to read the shadow password file.
# Change below to suit your setup. user = radius group = shadow
```

Please understand that giving anything except root read permissions to
the /etc/shadow file is something that you want to think a bit upon!!

[arabic, start=2]
. NOTES
+
None.
. TODO:
+
Real PAM support, figure out how we can write a module that will make it
blend in with PAM more seamlessly. With this, we can replace the
DENY_SHELL with something more flexible such as a database.

.EXAMPLE:

```
DEFAULT Auth-Type = Pam, NAS-IP-Address = 206.97.64.5 Service-Type =
Framed-User, Framed-Protocol = PPP, Framed-IP-Address = 255.255.255.254,
Filter-Id = std.ppp, Framed-MTU = 1500, Framed-Compression =
Van-Jacobson-TCP-IP DEFAULT Auth-Type = Pam, Pam-Auth = radius2,
NAS-IP-Address = 127.0.0.1 Service-Type = Framed-User, Framed-Protocol =
PPP, Framed-IP-Address = 255.255.255.254, Filter-Id = std.ppp,
Framed-MTU = 1500, Framed-Compression = Van-Jacobson-TCP-IP
```