Merge tag 'audit-pr-20211019' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoor...
[platform/kernel/linux-starfive.git] / net / 802 / p8022.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *      NET3:   Support for 802.2 demultiplexing off Ethernet
4  *
5  *              Demultiplex 802.2 encoded protocols. We match the entry by the
6  *              SSAP/DSAP pair and then deliver to the registered datalink that
7  *              matches. The control byte is ignored and handling of such items
8  *              is up to the routine passed the frame.
9  *
10  *              Unlike the 802.3 datalink we have a list of 802.2 entries as
11  *              there are multiple protocols to demux. The list is currently
12  *              short (3 or 4 entries at most). The current demux assumes this.
13  */
14 #include <linux/module.h>
15 #include <linux/netdevice.h>
16 #include <linux/skbuff.h>
17 #include <linux/slab.h>
18 #include <net/datalink.h>
19 #include <linux/mm.h>
20 #include <linux/in.h>
21 #include <linux/init.h>
22 #include <net/llc.h>
23 #include <net/p8022.h>
24
25 static int p8022_request(struct datalink_proto *dl, struct sk_buff *skb,
26                          unsigned char *dest)
27 {
28         llc_build_and_send_ui_pkt(dl->sap, skb, dest, dl->sap->laddr.lsap);
29         return 0;
30 }
31
32 struct datalink_proto *register_8022_client(unsigned char type,
33                                             int (*func)(struct sk_buff *skb,
34                                                         struct net_device *dev,
35                                                         struct packet_type *pt,
36                                                         struct net_device *orig_dev))
37 {
38         struct datalink_proto *proto;
39
40         proto = kmalloc(sizeof(*proto), GFP_ATOMIC);
41         if (proto) {
42                 proto->type[0]          = type;
43                 proto->header_length    = 3;
44                 proto->request          = p8022_request;
45                 proto->sap = llc_sap_open(type, func);
46                 if (!proto->sap) {
47                         kfree(proto);
48                         proto = NULL;
49                 }
50         }
51         return proto;
52 }
53
54 void unregister_8022_client(struct datalink_proto *proto)
55 {
56         llc_sap_put(proto->sap);
57         kfree(proto);
58 }
59
60 EXPORT_SYMBOL(register_8022_client);
61 EXPORT_SYMBOL(unregister_8022_client);
62
63 MODULE_LICENSE("GPL");