# -*- text -*-
######################################################################
#
#  The server can originate Change of Authorization (CoA) or
#  Disconnect request packets.  These packets are used to dynamically
#  change the parameters of a users session (bandwidth, etc.), or
#  to forcibly disconnect the user.
#
#  There are some caveats.  Not all NAS vendors support this
#  functionality.  Even for the ones that do, it may be difficult to
#  find out what needs to go into a CoA-Request or Disconnect-Request
#  packet.  All we can suggest is to read the NAS documentation
#  available from the vendor.  That documentation SHOULD describe
#  what information their equipment needs to see in a CoA packet.
#
#  This information is usually a list of attributes such as:
#
#	NAS-IP-Address (or NAS-IPv6 address)
#	NAS-Identifier
#	User-Name
#	Acct-Session-Id
#
#  CoA packets can be originated when a normal Access-Request or
#  Accounting-Request packet is received.  Simply update the
#  "coa" list:
#
#	update coa {
#	       &User-Name = "%{User-Name}"
#	       &Acct-Session-Id = "%{Acct-Session-Id}"
#	       &NAS-IP-Address = "%{NAS-IP-Address}"
#	}
#
#  And the CoA packet will be sent.  You can also send Disconnect
#  packets by using "update disconnect { ...".
#
#  This "update coa" entry can be placed in any section (authorize,
#  preacct, etc.), EXCEPT for pre-proxy and post-proxy.  The CoA
#  packets CANNOT be sent if the original request has been proxied.
#
#  The CoA functionality works best when the RADIUS server and
#  the NAS receiving CoA packets are on the same network.
#
#  If "update coa { ... " is used, and then later it becomes necessary
#  to not send a CoA request, the following example can suppress the
#  CoA packet:
#
#	update control {
#		&Send-CoA-Request = No
#	}
#
#  The default destination of a CoA packet is the NAS (or client)
#  the sent the original Access-Request or Accounting-Request.  See
#  raddb/clients.conf for a "coa_server" configuration that ties
#  a client to a specific home server, or to a home server pool.
#
#  If you need to send the packet to a different destination, update
#  the "coa" list with one of:
#
#	Packet-Dst-IP-Address = ...
#	Packet-Dst-IPv6-Address = ...
#	Home-Server-Pool = ...
#
#  That specifies an Ipv4 or IPv6 address, or a home server pool
#  (such as the "coa" pool example below).  This use is not
#  recommended, however,  It is much better to point the client
#  configuration directly at the CoA server/pool, as outlined
#  earlier.
#
#  If the CoA port is non-standard, you can also set:
#
#	Packet-Dst-Port
#
#  to have the value of the port.
#
######################################################################

#
#  When CoA packets are sent to a NAS, the NAS is acting as a
#  server (see RFC 5176).  i.e. it has a type (accepts CoA and/or
#  Disconnect packets), an IP address (or IPv6 address), a
#  destination port, and a shared secret.
#
home_server example-coa {
	type = coa

	#
	#  Note that a home server of type "coa" MUST be a real NAS,
	#  with an ipaddr or ipv6addr.  It CANNOT point to a virtual
	#  server.
	#
	#  Change this IP address to the IP address of the NAS.
	#
	ipaddr = 192.0.2.42
	port = 3799

	#  This secret SHOULD NOT be the same as the shared
	#  secret in a "client" section.
	secret = testing1234

	#
	#  All of the rest of the home_server configuration items can
	#  go here, including src_ipaddr,
	#  require_message_authenticator, etc.
	#

	#  CoA specific parameters.  See raddb/proxy.conf for details.
	coa {
		irt = 2
		mrt = 16
		mrc = 5
		mrd = 30
	}
}

#
#  CoA servers can be put into pools, just like normal servers.
#
home_server_pool coa {
	type = fail-over

	# Point to the CoA server above.
	home_server = example-coa

	#  CoA requests are run through the pre-proxy section.
	#  CoA responses are run through the post-proxy section.
	virtual_server = originate-coa.example.com

	#
	#  Home server pools of type "coa" cannot (currently) have
	#  a "fallback" configuration.
	#
}

#
#  When this virtual server is run, the original request has FINISHED
#  processing.  i.e. the reply has already been sent to the NAS.
#  You can access the attributes in the original packet, reply, and
#  control items, but changing them will have NO EFFECT.
#
#  The CoA packet is in the "proxy-request" attribute list.
#  The CoA reply (if any) is in the "proxy-reply" attribute list.
#
server originate-coa.example.com {
  pre-proxy {
	update proxy-request {
		NAS-IP-Address = 192.0.2.42
	}
  }

  #
  # Handle the responses here.
  #
  post-proxy {
	switch &proxy-reply:Packet-Type {
		case CoA-ACK {
			ok
		}

		case CoA-NAK {
			# the NAS didn't like the CoA request
			ok
		}

		case Disconnect-ACK {
			ok
		}

		case Disconnect-NAK {
			# the NAS didn't like the Disconnect request
			ok
		}

		# Invalid packet type.  This shouldn't happen.
		case {
		     fail
		}
	}

	#
	#  These methods are run when there is NO response
	#  to the request.
	#
	Post-Proxy-Type Fail-CoA {
		ok
	}

	Post-Proxy-Type Fail-Disconnect {
		ok
	}
  }
}
