1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * INET protocol dispatch tables.
8 *
9 * Authors: Ross Biro
10 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 *
12 * Fixes:
13 * Alan Cox : Ahah! udp icmp errors don't work because
14 * udp_err is never called!
15 * Alan Cox : Added new fields for init and ready for
16 * proper fragmentation (_NO_ 4K limits!)
17 * Richard Colella : Hang on hash collision
18 * Vince Laviano : Modified inet_del_protocol() to correctly
19 * maintain copy bit.
20 */
21 #include <linux/cache.h>
22 #include <linux/module.h>
23 #include <linux/netdevice.h>
24 #include <linux/spinlock.h>
25 #include <net/protocol.h>
26
27 struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS] __read_mostly;
28 EXPORT_SYMBOL(inet_protos);
29 const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS] __read_mostly;
30 EXPORT_SYMBOL(inet_offloads);
31
inet_add_protocol(const struct net_protocol * prot,unsigned char protocol)32 int inet_add_protocol(const struct net_protocol *prot, unsigned char protocol)
33 {
34 if (!prot->netns_ok) {
35 pr_err("Protocol %u is not namespace aware, cannot register.\n",
36 protocol);
37 return -EINVAL;
38 }
39
40 return !cmpxchg((const struct net_protocol **)&inet_protos[protocol],
41 NULL, prot) ? 0 : -1;
42 }
43 EXPORT_SYMBOL(inet_add_protocol);
44
inet_add_offload(const struct net_offload * prot,unsigned char protocol)45 int inet_add_offload(const struct net_offload *prot, unsigned char protocol)
46 {
47 return !cmpxchg((const struct net_offload **)&inet_offloads[protocol],
48 NULL, prot) ? 0 : -1;
49 }
50 EXPORT_SYMBOL(inet_add_offload);
51
inet_del_protocol(const struct net_protocol * prot,unsigned char protocol)52 int inet_del_protocol(const struct net_protocol *prot, unsigned char protocol)
53 {
54 int ret;
55
56 ret = (cmpxchg((const struct net_protocol **)&inet_protos[protocol],
57 prot, NULL) == prot) ? 0 : -1;
58
59 synchronize_net();
60
61 return ret;
62 }
63 EXPORT_SYMBOL(inet_del_protocol);
64
inet_del_offload(const struct net_offload * prot,unsigned char protocol)65 int inet_del_offload(const struct net_offload *prot, unsigned char protocol)
66 {
67 int ret;
68
69 ret = (cmpxchg((const struct net_offload **)&inet_offloads[protocol],
70 prot, NULL) == prot) ? 0 : -1;
71
72 synchronize_net();
73
74 return ret;
75 }
76 EXPORT_SYMBOL(inet_del_offload);
77