1/*
2 *	NET3:	Support for 802.2 demultiplexing off Ethernet (Token ring
3 *		is kept separate see p8022tr.c)
4 *		This program is free software; you can redistribute it and/or
5 *		modify it under the terms of the GNU General Public License
6 *		as published by the Free Software Foundation; either version
7 *		2 of the License, or (at your option) any later version.
8 *
9 *		Demultiplex 802.2 encoded protocols. We match the entry by the
10 *		SSAP/DSAP pair and then deliver to the registered datalink that
11 *		matches. The control byte is ignored and handling of such items
12 *		is up to the routine passed the frame.
13 *
14 *		Unlike the 802.3 datalink we have a list of 802.2 entries as
15 *		there are multiple protocols to demux. The list is currently
16 *		short (3 or 4 entries at most). The current demux assumes this.
17 */
18#include <linux/module.h>
19#include <linux/netdevice.h>
20#include <linux/skbuff.h>
21#include <linux/slab.h>
22#include <net/datalink.h>
23#include <linux/mm.h>
24#include <linux/in.h>
25#include <linux/init.h>
26#include <net/llc.h>
27#include <net/p8022.h>
28
29static int p8022_request(struct datalink_proto *dl, struct sk_buff *skb,
30			 unsigned char *dest)
31{
32	llc_build_and_send_ui_pkt(dl->sap, skb, dest, dl->sap->laddr.lsap);
33	return 0;
34}
35
36struct datalink_proto *register_8022_client(unsigned char type,
37					    int (*func)(struct sk_buff *skb,
38							struct net_device *dev,
39							struct packet_type *pt,
40							struct net_device *orig_dev))
41{
42	struct datalink_proto *proto;
43
44	proto = kmalloc(sizeof(*proto), GFP_ATOMIC);
45	if (proto) {
46		proto->type[0]		= type;
47		proto->header_length	= 3;
48		proto->request		= p8022_request;
49		proto->sap = llc_sap_open(type, func);
50		if (!proto->sap) {
51			kfree(proto);
52			proto = NULL;
53		}
54	}
55	return proto;
56}
57
58void unregister_8022_client(struct datalink_proto *proto)
59{
60	llc_sap_put(proto->sap);
61	kfree(proto);
62}
63
64EXPORT_SYMBOL(register_8022_client);
65EXPORT_SYMBOL(unregister_8022_client);
66
67MODULE_LICENSE("GPL");
68