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;
19
20#ifdef CONFIG_SYSCTL
21static int mptcp_pm_type_max = __MPTCP_PM_TYPE_MAX;
22#endif
23
24struct mptcp_pernet {
25#ifdef CONFIG_SYSCTL
26 struct ctl_table_header *ctl_table_hdr;
27#endif
28
29 unsigned int add_addr_timeout;
30 unsigned int close_timeout;
31 unsigned int stale_loss_cnt;
32 u8 mptcp_enabled;
33 u8 checksum_enabled;
34 u8 allow_join_initial_addr_port;
35 u8 pm_type;
36 char scheduler[MPTCP_SCHED_NAME_MAX];
37};
38
39static struct mptcp_pernet *mptcp_get_pernet(const struct net *net)
40{
41 return net_generic(net, id: mptcp_pernet_id);
42}
43
44int mptcp_is_enabled(const struct net *net)
45{
46 return mptcp_get_pernet(net)->mptcp_enabled;
47}
48
49unsigned int mptcp_get_add_addr_timeout(const struct net *net)
50{
51 return mptcp_get_pernet(net)->add_addr_timeout;
52}
53
54int mptcp_is_checksum_enabled(const struct net *net)
55{
56 return mptcp_get_pernet(net)->checksum_enabled;
57}
58
59int mptcp_allow_join_id0(const struct net *net)
60{
61 return mptcp_get_pernet(net)->allow_join_initial_addr_port;
62}
63
64unsigned int mptcp_stale_loss_cnt(const struct net *net)
65{
66 return mptcp_get_pernet(net)->stale_loss_cnt;
67}
68
69unsigned int mptcp_close_timeout(const struct sock *sk)
70{
71 if (sock_flag(sk, flag: SOCK_DEAD))
72 return TCP_TIMEWAIT_LEN;
73 return mptcp_get_pernet(net: sock_net(sk))->close_timeout;
74}
75
76int mptcp_get_pm_type(const struct net *net)
77{
78 return mptcp_get_pernet(net)->pm_type;
79}
80
81const char *mptcp_get_scheduler(const struct net *net)
82{
83 return mptcp_get_pernet(net)->scheduler;
84}
85
86static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet)
87{
88 pernet->mptcp_enabled = 1;
89 pernet->add_addr_timeout = TCP_RTO_MAX;
90 pernet->close_timeout = TCP_TIMEWAIT_LEN;
91 pernet->checksum_enabled = 0;
92 pernet->allow_join_initial_addr_port = 1;
93 pernet->stale_loss_cnt = 4;
94 pernet->pm_type = MPTCP_PM_TYPE_KERNEL;
95 strcpy(p: pernet->scheduler, q: "default");
96}
97
98#ifdef CONFIG_SYSCTL
99static struct ctl_table mptcp_sysctl_table[] = {
100 {
101 .procname = "enabled",
102 .maxlen = sizeof(u8),
103 .mode = 0644,
104 /* users with CAP_NET_ADMIN or root (not and) can change this
105 * value, same as other sysctl or the 'net' tree.
106 */
107 .proc_handler = proc_dou8vec_minmax,
108 .extra1 = SYSCTL_ZERO,
109 .extra2 = SYSCTL_ONE
110 },
111 {
112 .procname = "add_addr_timeout",
113 .maxlen = sizeof(unsigned int),
114 .mode = 0644,
115 .proc_handler = proc_dointvec_jiffies,
116 },
117 {
118 .procname = "checksum_enabled",
119 .maxlen = sizeof(u8),
120 .mode = 0644,
121 .proc_handler = proc_dou8vec_minmax,
122 .extra1 = SYSCTL_ZERO,
123 .extra2 = SYSCTL_ONE
124 },
125 {
126 .procname = "allow_join_initial_addr_port",
127 .maxlen = sizeof(u8),
128 .mode = 0644,
129 .proc_handler = proc_dou8vec_minmax,
130 .extra1 = SYSCTL_ZERO,
131 .extra2 = SYSCTL_ONE
132 },
133 {
134 .procname = "stale_loss_cnt",
135 .maxlen = sizeof(unsigned int),
136 .mode = 0644,
137 .proc_handler = proc_douintvec_minmax,
138 },
139 {
140 .procname = "pm_type",
141 .maxlen = sizeof(u8),
142 .mode = 0644,
143 .proc_handler = proc_dou8vec_minmax,
144 .extra1 = SYSCTL_ZERO,
145 .extra2 = &mptcp_pm_type_max
146 },
147 {
148 .procname = "scheduler",
149 .maxlen = MPTCP_SCHED_NAME_MAX,
150 .mode = 0644,
151 .proc_handler = proc_dostring,
152 },
153 {
154 .procname = "close_timeout",
155 .maxlen = sizeof(unsigned int),
156 .mode = 0644,
157 .proc_handler = proc_dointvec_jiffies,
158 },
159 {}
160};
161
162static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet)
163{
164 struct ctl_table_header *hdr;
165 struct ctl_table *table;
166
167 table = mptcp_sysctl_table;
168 if (!net_eq(net1: net, net2: &init_net)) {
169 table = kmemdup(p: table, size: sizeof(mptcp_sysctl_table), GFP_KERNEL);
170 if (!table)
171 goto err_alloc;
172 }
173
174 table[0].data = &pernet->mptcp_enabled;
175 table[1].data = &pernet->add_addr_timeout;
176 table[2].data = &pernet->checksum_enabled;
177 table[3].data = &pernet->allow_join_initial_addr_port;
178 table[4].data = &pernet->stale_loss_cnt;
179 table[5].data = &pernet->pm_type;
180 table[6].data = &pernet->scheduler;
181 table[7].data = &pernet->close_timeout;
182
183 hdr = register_net_sysctl_sz(net, MPTCP_SYSCTL_PATH, table,
184 ARRAY_SIZE(mptcp_sysctl_table));
185 if (!hdr)
186 goto err_reg;
187
188 pernet->ctl_table_hdr = hdr;
189
190 return 0;
191
192err_reg:
193 if (!net_eq(net1: net, net2: &init_net))
194 kfree(objp: table);
195err_alloc:
196 return -ENOMEM;
197}
198
199static void mptcp_pernet_del_table(struct mptcp_pernet *pernet)
200{
201 struct ctl_table *table = pernet->ctl_table_hdr->ctl_table_arg;
202
203 unregister_net_sysctl_table(header: pernet->ctl_table_hdr);
204
205 kfree(objp: table);
206}
207
208#else
209
210static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet)
211{
212 return 0;
213}
214
215static void mptcp_pernet_del_table(struct mptcp_pernet *pernet) {}
216
217#endif /* CONFIG_SYSCTL */
218
219static int __net_init mptcp_net_init(struct net *net)
220{
221 struct mptcp_pernet *pernet = mptcp_get_pernet(net);
222
223 mptcp_pernet_set_defaults(pernet);
224
225 return mptcp_pernet_new_table(net, pernet);
226}
227
228/* Note: the callback will only be called per extra netns */
229static void __net_exit mptcp_net_exit(struct net *net)
230{
231 struct mptcp_pernet *pernet = mptcp_get_pernet(net);
232
233 mptcp_pernet_del_table(pernet);
234}
235
236static struct pernet_operations mptcp_pernet_ops = {
237 .init = mptcp_net_init,
238 .exit = mptcp_net_exit,
239 .id = &mptcp_pernet_id,
240 .size = sizeof(struct mptcp_pernet),
241};
242
243void __init mptcp_init(void)
244{
245 mptcp_join_cookie_init();
246 mptcp_proto_init();
247
248 if (register_pernet_subsys(&mptcp_pernet_ops) < 0)
249 panic(fmt: "Failed to register MPTCP pernet subsystem.\n");
250}
251
252#if IS_ENABLED(CONFIG_MPTCP_IPV6)
253int __init mptcpv6_init(void)
254{
255 int err;
256
257 err = mptcp_proto_v6_init();
258
259 return err;
260}
261#endif
262

source code of linux/net/mptcp/ctrl.c