1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * INET An implementation of the TCP/IP protocol suite for the LINUX
4*4882a593Smuzhiyun * operating system. INET is implemented using the BSD Socket
5*4882a593Smuzhiyun * interface as the means of communication with the user level.
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun * INET protocol dispatch tables.
8*4882a593Smuzhiyun *
9*4882a593Smuzhiyun * Authors: Ross Biro
10*4882a593Smuzhiyun * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11*4882a593Smuzhiyun *
12*4882a593Smuzhiyun * Fixes:
13*4882a593Smuzhiyun * Alan Cox : Ahah! udp icmp errors don't work because
14*4882a593Smuzhiyun * udp_err is never called!
15*4882a593Smuzhiyun * Alan Cox : Added new fields for init and ready for
16*4882a593Smuzhiyun * proper fragmentation (_NO_ 4K limits!)
17*4882a593Smuzhiyun * Richard Colella : Hang on hash collision
18*4882a593Smuzhiyun * Vince Laviano : Modified inet_del_protocol() to correctly
19*4882a593Smuzhiyun * maintain copy bit.
20*4882a593Smuzhiyun */
21*4882a593Smuzhiyun #include <linux/cache.h>
22*4882a593Smuzhiyun #include <linux/module.h>
23*4882a593Smuzhiyun #include <linux/netdevice.h>
24*4882a593Smuzhiyun #include <linux/spinlock.h>
25*4882a593Smuzhiyun #include <net/protocol.h>
26*4882a593Smuzhiyun
27*4882a593Smuzhiyun struct net_protocol __rcu *inet_protos[MAX_INET_PROTOS] __read_mostly;
28*4882a593Smuzhiyun EXPORT_SYMBOL(inet_protos);
29*4882a593Smuzhiyun const struct net_offload __rcu *inet_offloads[MAX_INET_PROTOS] __read_mostly;
30*4882a593Smuzhiyun EXPORT_SYMBOL(inet_offloads);
31*4882a593Smuzhiyun
inet_add_protocol(const struct net_protocol * prot,unsigned char protocol)32*4882a593Smuzhiyun int inet_add_protocol(const struct net_protocol *prot, unsigned char protocol)
33*4882a593Smuzhiyun {
34*4882a593Smuzhiyun if (!prot->netns_ok) {
35*4882a593Smuzhiyun pr_err("Protocol %u is not namespace aware, cannot register.\n",
36*4882a593Smuzhiyun protocol);
37*4882a593Smuzhiyun return -EINVAL;
38*4882a593Smuzhiyun }
39*4882a593Smuzhiyun
40*4882a593Smuzhiyun return !cmpxchg((const struct net_protocol **)&inet_protos[protocol],
41*4882a593Smuzhiyun NULL, prot) ? 0 : -1;
42*4882a593Smuzhiyun }
43*4882a593Smuzhiyun EXPORT_SYMBOL(inet_add_protocol);
44*4882a593Smuzhiyun
inet_add_offload(const struct net_offload * prot,unsigned char protocol)45*4882a593Smuzhiyun int inet_add_offload(const struct net_offload *prot, unsigned char protocol)
46*4882a593Smuzhiyun {
47*4882a593Smuzhiyun return !cmpxchg((const struct net_offload **)&inet_offloads[protocol],
48*4882a593Smuzhiyun NULL, prot) ? 0 : -1;
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun EXPORT_SYMBOL(inet_add_offload);
51*4882a593Smuzhiyun
inet_del_protocol(const struct net_protocol * prot,unsigned char protocol)52*4882a593Smuzhiyun int inet_del_protocol(const struct net_protocol *prot, unsigned char protocol)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun int ret;
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun ret = (cmpxchg((const struct net_protocol **)&inet_protos[protocol],
57*4882a593Smuzhiyun prot, NULL) == prot) ? 0 : -1;
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun synchronize_net();
60*4882a593Smuzhiyun
61*4882a593Smuzhiyun return ret;
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun EXPORT_SYMBOL(inet_del_protocol);
64*4882a593Smuzhiyun
inet_del_offload(const struct net_offload * prot,unsigned char protocol)65*4882a593Smuzhiyun int inet_del_offload(const struct net_offload *prot, unsigned char protocol)
66*4882a593Smuzhiyun {
67*4882a593Smuzhiyun int ret;
68*4882a593Smuzhiyun
69*4882a593Smuzhiyun ret = (cmpxchg((const struct net_offload **)&inet_offloads[protocol],
70*4882a593Smuzhiyun prot, NULL) == prot) ? 0 : -1;
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun synchronize_net();
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun return ret;
75*4882a593Smuzhiyun }
76*4882a593Smuzhiyun EXPORT_SYMBOL(inet_del_offload);
77