1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * INET protocol dispatch tables.
7 *
8 * Authors: Ross Biro
9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
10 *
11 * Fixes:
12 * Alan Cox : Ahah! udp icmp errors don't work because
13 * udp_err is never called!
14 * Alan Cox : Added new fields for init and ready for
15 * proper fragmentation (_NO_ 4K limits!)
16 * Richard Colella : Hang on hash collision
17 * Vince Laviano : Modified inet_del_protocol() to correctly
18 * maintain copy bit.
19 *
20 * This program is free software; you can redistribute it and/or
21 * modify it under the terms of the GNU General Public License
22 * as published by the Free Software Foundation; either version
23 * 2 of the License, or (at your option) any later version.
24 */
25 #include <linux/cache.h>
26 #include <linux/module.h>
27 #include <linux/netdevice.h>
28 #include <linux/spinlock.h>
29 #include <net/protocol.h>
30
31 struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS] __read_mostly;
32 const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS] __read_mostly;
33 EXPORT_SYMBOL(inet_offloads);
34
inet_add_protocol(const struct net_protocol * prot,unsigned char protocol)35 int inet_add_protocol(const struct net_protocol *prot, unsigned char protocol)
36 {
37 if (!prot->netns_ok) {
38 pr_err("Protocol %u is not namespace aware, cannot register.\n",
39 protocol);
40 return -EINVAL;
41 }
42
43 return !cmpxchg((const struct net_protocol **)&inet_protos[protocol],
44 NULL, prot) ? 0 : -1;
45 }
46 EXPORT_SYMBOL(inet_add_protocol);
47
inet_add_offload(const struct net_offload * prot,unsigned char protocol)48 int inet_add_offload(const struct net_offload *prot, unsigned char protocol)
49 {
50 return !cmpxchg((const struct net_offload **)&inet_offloads[protocol],
51 NULL, prot) ? 0 : -1;
52 }
53 EXPORT_SYMBOL(inet_add_offload);
54
inet_del_protocol(const struct net_protocol * prot,unsigned char protocol)55 int inet_del_protocol(const struct net_protocol *prot, unsigned char protocol)
56 {
57 int ret;
58
59 ret = (cmpxchg((const struct net_protocol **)&inet_protos[protocol],
60 prot, NULL) == prot) ? 0 : -1;
61
62 synchronize_net();
63
64 return ret;
65 }
66 EXPORT_SYMBOL(inet_del_protocol);
67
inet_del_offload(const struct net_offload * prot,unsigned char protocol)68 int inet_del_offload(const struct net_offload *prot, unsigned char protocol)
69 {
70 int ret;
71
72 ret = (cmpxchg((const struct net_offload **)&inet_offloads[protocol],
73 prot, NULL) == prot) ? 0 : -1;
74
75 synchronize_net();
76
77 return ret;
78 }
79 EXPORT_SYMBOL(inet_del_offload);
80
