Linux kernel mirror (for testing)
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linux
1// SPDX-License-Identifier: GPL-2.0
2/* Multipath TCP
3 *
4 * Copyright (c) 2019, Tessares SA.
5 */
6
7#ifdef CONFIG_SYSCTL
8#include <linux/sysctl.h>
9#endif
10
11#include <net/net_namespace.h>
12#include <net/netns/generic.h>
13
14#include "protocol.h"
15
16#define MPTCP_SYSCTL_PATH "net/mptcp"
17
18static int mptcp_pernet_id;
19struct mptcp_pernet {
20#ifdef CONFIG_SYSCTL
21 struct ctl_table_header *ctl_table_hdr;
22#endif
23
24 u8 mptcp_enabled;
25 unsigned int add_addr_timeout;
26 u8 checksum_enabled;
27 u8 allow_join_initial_addr_port;
28};
29
30static struct mptcp_pernet *mptcp_get_pernet(struct net *net)
31{
32 return net_generic(net, mptcp_pernet_id);
33}
34
35int mptcp_is_enabled(struct net *net)
36{
37 return mptcp_get_pernet(net)->mptcp_enabled;
38}
39
40unsigned int mptcp_get_add_addr_timeout(struct net *net)
41{
42 return mptcp_get_pernet(net)->add_addr_timeout;
43}
44
45int mptcp_is_checksum_enabled(struct net *net)
46{
47 return mptcp_get_pernet(net)->checksum_enabled;
48}
49
50int mptcp_allow_join_id0(struct net *net)
51{
52 return mptcp_get_pernet(net)->allow_join_initial_addr_port;
53}
54
55static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet)
56{
57 pernet->mptcp_enabled = 1;
58 pernet->add_addr_timeout = TCP_RTO_MAX;
59 pernet->checksum_enabled = 0;
60 pernet->allow_join_initial_addr_port = 1;
61}
62
63#ifdef CONFIG_SYSCTL
64static struct ctl_table mptcp_sysctl_table[] = {
65 {
66 .procname = "enabled",
67 .maxlen = sizeof(u8),
68 .mode = 0644,
69 /* users with CAP_NET_ADMIN or root (not and) can change this
70 * value, same as other sysctl or the 'net' tree.
71 */
72 .proc_handler = proc_dou8vec_minmax,
73 .extra1 = SYSCTL_ZERO,
74 .extra2 = SYSCTL_ONE
75 },
76 {
77 .procname = "add_addr_timeout",
78 .maxlen = sizeof(unsigned int),
79 .mode = 0644,
80 .proc_handler = proc_dointvec_jiffies,
81 },
82 {
83 .procname = "checksum_enabled",
84 .maxlen = sizeof(u8),
85 .mode = 0644,
86 .proc_handler = proc_dou8vec_minmax,
87 .extra1 = SYSCTL_ZERO,
88 .extra2 = SYSCTL_ONE
89 },
90 {
91 .procname = "allow_join_initial_addr_port",
92 .maxlen = sizeof(u8),
93 .mode = 0644,
94 .proc_handler = proc_dou8vec_minmax,
95 .extra1 = SYSCTL_ZERO,
96 .extra2 = SYSCTL_ONE
97 },
98 {}
99};
100
101static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet)
102{
103 struct ctl_table_header *hdr;
104 struct ctl_table *table;
105
106 table = mptcp_sysctl_table;
107 if (!net_eq(net, &init_net)) {
108 table = kmemdup(table, sizeof(mptcp_sysctl_table), GFP_KERNEL);
109 if (!table)
110 goto err_alloc;
111 }
112
113 table[0].data = &pernet->mptcp_enabled;
114 table[1].data = &pernet->add_addr_timeout;
115 table[2].data = &pernet->checksum_enabled;
116 table[3].data = &pernet->allow_join_initial_addr_port;
117
118 hdr = register_net_sysctl(net, MPTCP_SYSCTL_PATH, table);
119 if (!hdr)
120 goto err_reg;
121
122 pernet->ctl_table_hdr = hdr;
123
124 return 0;
125
126err_reg:
127 if (!net_eq(net, &init_net))
128 kfree(table);
129err_alloc:
130 return -ENOMEM;
131}
132
133static void mptcp_pernet_del_table(struct mptcp_pernet *pernet)
134{
135 struct ctl_table *table = pernet->ctl_table_hdr->ctl_table_arg;
136
137 unregister_net_sysctl_table(pernet->ctl_table_hdr);
138
139 kfree(table);
140}
141
142#else
143
144static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet)
145{
146 return 0;
147}
148
149static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) {}
150
151#endif /* CONFIG_SYSCTL */
152
153static int __net_init mptcp_net_init(struct net *net)
154{
155 struct mptcp_pernet *pernet = mptcp_get_pernet(net);
156
157 mptcp_pernet_set_defaults(pernet);
158
159 return mptcp_pernet_new_table(net, pernet);
160}
161
162/* Note: the callback will only be called per extra netns */
163static void __net_exit mptcp_net_exit(struct net *net)
164{
165 struct mptcp_pernet *pernet = mptcp_get_pernet(net);
166
167 mptcp_pernet_del_table(pernet);
168}
169
170static struct pernet_operations mptcp_pernet_ops = {
171 .init = mptcp_net_init,
172 .exit = mptcp_net_exit,
173 .id = &mptcp_pernet_id,
174 .size = sizeof(struct mptcp_pernet),
175};
176
177void __init mptcp_init(void)
178{
179 mptcp_join_cookie_init();
180 mptcp_proto_init();
181
182 if (register_pernet_subsys(&mptcp_pernet_ops) < 0)
183 panic("Failed to register MPTCP pernet subsystem.\n");
184}
185
186#if IS_ENABLED(CONFIG_MPTCP_IPV6)
187int __init mptcpv6_init(void)
188{
189 int err;
190
191 err = mptcp_proto_v6_init();
192
193 return err;
194}
195#endif