Authentication failure via PAP

[Thomas Schmitz]

Hi,

I'm using Freeradius 1.1.6 inside a Solaris 10 zone and compiled 
it from vanilla sources. I configured rlm_ldap since the 
usernames and cleartext-passwords are stored in an LDAP 
directory and it works just fine for applications like Cisco-VPN 
or 802.1X EAP-TTLS. Now I wanted to set up the Captive Portal of 
pfsense/m0n0wall to authenticate against radius, which is using 
PAP for password transmission but authentication always fails 
even if I triple-check the entered user credentials.

The freeradius log always says:
Auth: Login incorrect (rlm_ldap: Bind as user failed): 
[my_username] (from client pfsensebox port 1 cli 
00:17:f2:xx:yy:zz)

Of course I also checked if the radius client is using the 
correct secret. I set auto_headers to "yes" as it is suggested 
in the rlm_pap manpage and put pap at the end of the authorize 
section.

I also included an excerpt of my radiusd.conf

---begin radiusd.conf---
modules {
        pap {
                auto_header = yes
        }
ldap {
                server = "ldapserver.mydomain.com"
                basedn = "ou=people,o=my organization,c=de"
                filter 
= "(uid=%{Stripped-User-Name:-%{User-Name}})"
                start_tls = no
                access_attr = "uid"
                dictionary_mapping = ${raddbdir}/ldap.attrmap
                ldap_connections_number = 5
                password_attribute = userPassword
                timeout = 4
                timelimit = 3
                net_timeout = 1
        }
}
authorize {
        auth_log
        chap
        mschap
        suffix
        eap
        ldap
        files
        daily
        pap
}

authenticate {
        pap
        chap
        mschap
        ldap
        eap
}
---end radiusd.conf---

Here is an output of radiusd -X:

---begin radiusd -X output---
rad_recv: Access-Request packet from host 111.222.333.444:51087, 
id=255, length=131
        NAS-IP-Address = 111.222.333.444
        NAS-Identifier = "pfsense.local"
        User-Name = "my_username"
        User-Password 
= "\301q\202\355g\264g)N\265\315\311\374\205i"
        Service-Type = Login-User
        NAS-Port-Type = Ethernet
        NAS-Port = 1
        Framed-IP-Address = 192.168.23.200
        Called-Station-Id = "00:01:02:xx:yy:zz"
        Calling-Station-Id = "00:17:f2:aa:bb:cc"
  Processing the authorize section of radiusd.conf
modcall: entering group authorize for request 0
radius_xlat:  '/opt/radiusd/var/log//radacct/auth-detail-200709'
rlm_detail: /opt/radiusd/var/log//radacct/auth-detail-%Y%m 
expands to /opt/radiusd/var/log//radacct/auth-detail-200709
  modcall[authorize]: module "auth_log" returns ok for request 0
  modcall[authorize]: module "chap" returns noop for request 0
  modcall[authorize]: module "mschap" returns noop for request 0
    rlm_realm: No '@' in User-Name = "my_username", looking up 
realm NULL
    rlm_realm: Found realm "NULL"
    rlm_realm: Adding Stripped-User-Name = "my_username"
    rlm_realm: Proxying request from user my_username to realm 
NULL
    rlm_realm: Adding Realm = "NULL"
    rlm_realm: Authentication realm is LOCAL.
  modcall[authorize]: module "suffix" returns noop for request 0
  rlm_eap: No EAP-Message, not doing EAP
  modcall[authorize]: module "eap" returns noop for request 0
rlm_ldap: - authorize
rlm_ldap: performing user authorization for my_username
radius_xlat:  '(uid=my_username)'
radius_xlat:  'ou=people,o=my organization,c=de'
rlm_ldap: ldap_get_conn: Checking Id: 0
rlm_ldap: ldap_get_conn: Got Id: 0
rlm_ldap: attempting LDAP reconnection
rlm_ldap: (re)connect to directory.fernuni-hagen.de:389, 
authentication 0
rlm_ldap: bind as / to directory.fernuni-hagen.de:389
rlm_ldap: waiting for bind result ...
rlm_ldap: Bind was successful
rlm_ldap: performing search in ou=people,o=my organization,c=de, 
with filter (uid=my_username)
rlm_ldap: checking if remote access for my_username is allowed by 
uid
rlm_ldap: looking for check items in directory...
rlm_ldap: Adding uid as User-Name, value my_username & op=21
rlm_ldap: looking for reply items in directory...
rlm_ldap: Setting Auth-Type = ldap
rlm_ldap: user my_username authorized to use remote access
rlm_ldap: ldap_release_conn: Release Id: 0
  modcall[authorize]: module "ldap" returns ok for request 0
  modcall[authorize]: module "files" returns notfound for request 
0
rlm_counter: Entering module authorize code
rlm_counter: Could not find Check item value pair
  modcall[authorize]: module "daily" returns noop for request 0
rlm_pap: WARNING! No "known good" password found for the user.  
Authentication may fail because of this.
  modcall[authorize]: module "pap" returns noop for request 0
modcall: leaving group authorize (returns ok) for request 0
  rad_check_password:  Found Auth-Type ldap
auth: type "ldap"
  Processing the authenticate section of radiusd.conf
modcall: entering group authenticate for request 0
rlm_ldap: - authenticate
rlm_ldap: login attempt by "my_username" with password "Áq?íg
´g)NµÍÉü?i"
rlm_ldap: user DN: uid=my_username,ou=People,o=my 
organization,c=de
rlm_ldap: (re)connect to directory.fernuni-hagen.de:389, 
authentication 1
rlm_ldap: bind as uid=my_username,ou=People,o=my 
organization,c=de/Áq?íg´g)NµÍÉü?i to 
directory.fernuni-hagen.de:389
rlm_ldap: waiting for bind result ...
rlm_ldap: Bind failed with invalid credentials
  modcall[authenticate]: module "ldap" returns reject for request 
0
modcall: leaving group authenticate (returns reject) for request 
0
auth: Failed to validate the user.
Login incorrect (rlm_ldap: Bind as user failed): [my_username] 
(from client pfsensebox port 1 cli 00:17:f2:aa:bb:cc)
  WARNING: Unprintable characters in the password. ?  
Double-check the shared secret on the server and the NAS!
---end radiusd -X output---

What seems very curious to me is that my password, though 
delivered in cleartext, seems broken since the password in the 
following line is actually not the real password:

rlm_ldap: login attempt by "my_username" with password "Áq?íg
´g)NµÍÉü?i"

Is it the client that does those nasty things or is my freeradius 
just misconfigured? How can I get it to work?

Thanks in advance,
Thomas