Freeradius AD LDAP Authentication

FreeRadius2 LDAP auth to Win2k12 AD for Cisco/Juniper login authentication.

• Have an existing AD. Create a few groups for read-write or read-only access. Let's use:
  • network-operators: router login permitted, read only
  • network-administrators: full admin/config access

• Install freeradius packages on your centos-ey server:
  • yum install freeradius freeradius-ldap

• Create an AD user for freeradius application to bind to LDAP. Let's call it 'freeradius'.

• /etc/raddb/modules/ldap:

ldap {
	server = "ad.yourcompany.com"
	port = 389
	start_tls = yes
	identity = "CN=freeradius,OU=Applications,DC=ad,DC=yourcompany,DC=com"
	password = password_goes_here
	basedn = "DC=ad,DC=yourcompany,DC=com"
	filter = "(&(sAMAccountName=%{Stripped-User-Name:-%{User-Name}}))"
	groupmembership_filter = "(|(&(objectClass=group)(member=%{control:Ldap-UserDn})))"
	groupmembership_attribute = memberOf
	edir_account_policy_check=no
	ldap_connections_number = 5
	timeout = 4
	timelimit = 3
	net_timeout = 1
	chase_referrals = yes
	rebind = yes
}

• Modifications to sites-enabled/default:
  • In the authorize {} section:
    • uncomment 'ldap'
    • comment 'files' (which refers to the users plain text file)
  • In the authenticate {} section, uncomment:

Auth-Type LDAP {
    ldap
}

• in the post-auth {} section add this section to do LDAP group to radius reply item mapping:

if (LDAP-Group == "network-administrators") {
	update reply {
		cisco-avpair = "shell:priv-lvl=15",
		Juniper-Local-User-Name = "superuser"
	}
}
elsif (LDAP-Group == "network-operators") {
	update reply {
		cisco-avpair = "shell:priv-lvl=1",
		Juniper-Local-User-Name = "op"
	}
}
else {
	reject
}

• Not going into detail of your router configs, but they will have to be configured to point to your RADIUS server. On the Juniper side the "op" and "superuser" referenced above will have to map to some classes and users:

system {
    login {
        class super-user-local {
            permissions all;
        }
        class operator-local {
            permissions [ clear network reset trace view ];
        }
        user superuser {
            uid 2000;
            class super-user-local;
        }
        user op {
            uid 2001;
            class operator-local;
        }
    }
}