xref: /linux/net/ipv6/sysctl_net_ipv6.c (revision 95298d63c67673c654c08952672d016212b26054)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * sysctl_net_ipv6.c: sysctl interface to net IPV6 subsystem.
4  *
5  * Changes:
6  * YOSHIFUJI Hideaki @USAGI:	added icmp sysctl table.
7  */
8 
9 #include <linux/mm.h>
10 #include <linux/sysctl.h>
11 #include <linux/in6.h>
12 #include <linux/ipv6.h>
13 #include <linux/slab.h>
14 #include <linux/export.h>
15 #include <net/ndisc.h>
16 #include <net/ipv6.h>
17 #include <net/addrconf.h>
18 #include <net/inet_frag.h>
19 #include <net/netevent.h>
20 #ifdef CONFIG_NETLABEL
21 #include <net/calipso.h>
22 #endif
23 
24 static int flowlabel_reflect_max = 0x7;
25 static int auto_flowlabels_min;
26 static int auto_flowlabels_max = IP6_AUTO_FLOW_LABEL_MAX;
27 
28 static int proc_rt6_multipath_hash_policy(struct ctl_table *table, int write,
29 					  void *buffer, size_t *lenp, loff_t *ppos)
30 {
31 	struct net *net;
32 	int ret;
33 
34 	net = container_of(table->data, struct net,
35 			   ipv6.sysctl.multipath_hash_policy);
36 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
37 	if (write && ret == 0)
38 		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
39 
40 	return ret;
41 }
42 
43 static struct ctl_table ipv6_table_template[] = {
44 	{
45 		.procname	= "bindv6only",
46 		.data		= &init_net.ipv6.sysctl.bindv6only,
47 		.maxlen		= sizeof(int),
48 		.mode		= 0644,
49 		.proc_handler	= proc_dointvec
50 	},
51 	{
52 		.procname	= "anycast_src_echo_reply",
53 		.data		= &init_net.ipv6.sysctl.anycast_src_echo_reply,
54 		.maxlen		= sizeof(int),
55 		.mode		= 0644,
56 		.proc_handler	= proc_dointvec
57 	},
58 	{
59 		.procname	= "flowlabel_consistency",
60 		.data		= &init_net.ipv6.sysctl.flowlabel_consistency,
61 		.maxlen		= sizeof(int),
62 		.mode		= 0644,
63 		.proc_handler	= proc_dointvec
64 	},
65 	{
66 		.procname	= "auto_flowlabels",
67 		.data		= &init_net.ipv6.sysctl.auto_flowlabels,
68 		.maxlen		= sizeof(int),
69 		.mode		= 0644,
70 		.proc_handler	= proc_dointvec_minmax,
71 		.extra1		= &auto_flowlabels_min,
72 		.extra2		= &auto_flowlabels_max
73 	},
74 	{
75 		.procname	= "fwmark_reflect",
76 		.data		= &init_net.ipv6.sysctl.fwmark_reflect,
77 		.maxlen		= sizeof(int),
78 		.mode		= 0644,
79 		.proc_handler	= proc_dointvec
80 	},
81 	{
82 		.procname	= "idgen_retries",
83 		.data		= &init_net.ipv6.sysctl.idgen_retries,
84 		.maxlen		= sizeof(int),
85 		.mode		= 0644,
86 		.proc_handler	= proc_dointvec,
87 	},
88 	{
89 		.procname	= "idgen_delay",
90 		.data		= &init_net.ipv6.sysctl.idgen_delay,
91 		.maxlen		= sizeof(int),
92 		.mode		= 0644,
93 		.proc_handler	= proc_dointvec_jiffies,
94 	},
95 	{
96 		.procname	= "flowlabel_state_ranges",
97 		.data		= &init_net.ipv6.sysctl.flowlabel_state_ranges,
98 		.maxlen		= sizeof(int),
99 		.mode		= 0644,
100 		.proc_handler	= proc_dointvec
101 	},
102 	{
103 		.procname	= "ip_nonlocal_bind",
104 		.data		= &init_net.ipv6.sysctl.ip_nonlocal_bind,
105 		.maxlen		= sizeof(int),
106 		.mode		= 0644,
107 		.proc_handler	= proc_dointvec
108 	},
109 	{
110 		.procname	= "flowlabel_reflect",
111 		.data		= &init_net.ipv6.sysctl.flowlabel_reflect,
112 		.maxlen		= sizeof(int),
113 		.mode		= 0644,
114 		.proc_handler	= proc_dointvec_minmax,
115 		.extra1		= SYSCTL_ZERO,
116 		.extra2		= &flowlabel_reflect_max,
117 	},
118 	{
119 		.procname	= "max_dst_opts_number",
120 		.data		= &init_net.ipv6.sysctl.max_dst_opts_cnt,
121 		.maxlen		= sizeof(int),
122 		.mode		= 0644,
123 		.proc_handler	= proc_dointvec
124 	},
125 	{
126 		.procname	= "max_hbh_opts_number",
127 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_cnt,
128 		.maxlen		= sizeof(int),
129 		.mode		= 0644,
130 		.proc_handler	= proc_dointvec
131 	},
132 	{
133 		.procname	= "max_dst_opts_length",
134 		.data		= &init_net.ipv6.sysctl.max_dst_opts_len,
135 		.maxlen		= sizeof(int),
136 		.mode		= 0644,
137 		.proc_handler	= proc_dointvec
138 	},
139 	{
140 		.procname	= "max_hbh_length",
141 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_len,
142 		.maxlen		= sizeof(int),
143 		.mode		= 0644,
144 		.proc_handler	= proc_dointvec
145 	},
146 	{
147 		.procname	= "fib_multipath_hash_policy",
148 		.data		= &init_net.ipv6.sysctl.multipath_hash_policy,
149 		.maxlen		= sizeof(int),
150 		.mode		= 0644,
151 		.proc_handler   = proc_rt6_multipath_hash_policy,
152 		.extra1		= SYSCTL_ZERO,
153 		.extra2		= SYSCTL_ONE,
154 	},
155 	{
156 		.procname	= "seg6_flowlabel",
157 		.data		= &init_net.ipv6.sysctl.seg6_flowlabel,
158 		.maxlen		= sizeof(int),
159 		.mode		= 0644,
160 		.proc_handler	= proc_dointvec
161 	},
162 	{ }
163 };
164 
165 static struct ctl_table ipv6_rotable[] = {
166 	{
167 		.procname	= "mld_max_msf",
168 		.data		= &sysctl_mld_max_msf,
169 		.maxlen		= sizeof(int),
170 		.mode		= 0644,
171 		.proc_handler	= proc_dointvec
172 	},
173 	{
174 		.procname	= "mld_qrv",
175 		.data		= &sysctl_mld_qrv,
176 		.maxlen		= sizeof(int),
177 		.mode		= 0644,
178 		.proc_handler	= proc_dointvec_minmax,
179 		.extra1		= SYSCTL_ONE
180 	},
181 #ifdef CONFIG_NETLABEL
182 	{
183 		.procname	= "calipso_cache_enable",
184 		.data		= &calipso_cache_enabled,
185 		.maxlen		= sizeof(int),
186 		.mode		= 0644,
187 		.proc_handler	= proc_dointvec,
188 	},
189 	{
190 		.procname	= "calipso_cache_bucket_size",
191 		.data		= &calipso_cache_bucketsize,
192 		.maxlen		= sizeof(int),
193 		.mode		= 0644,
194 		.proc_handler	= proc_dointvec,
195 	},
196 #endif /* CONFIG_NETLABEL */
197 	{ }
198 };
199 
200 static int __net_init ipv6_sysctl_net_init(struct net *net)
201 {
202 	struct ctl_table *ipv6_table;
203 	struct ctl_table *ipv6_route_table;
204 	struct ctl_table *ipv6_icmp_table;
205 	int err, i;
206 
207 	err = -ENOMEM;
208 	ipv6_table = kmemdup(ipv6_table_template, sizeof(ipv6_table_template),
209 			     GFP_KERNEL);
210 	if (!ipv6_table)
211 		goto out;
212 	/* Update the variables to point into the current struct net */
213 	for (i = 0; i < ARRAY_SIZE(ipv6_table_template) - 1; i++)
214 		ipv6_table[i].data += (void *)net - (void *)&init_net;
215 
216 	ipv6_route_table = ipv6_route_sysctl_init(net);
217 	if (!ipv6_route_table)
218 		goto out_ipv6_table;
219 
220 	ipv6_icmp_table = ipv6_icmp_sysctl_init(net);
221 	if (!ipv6_icmp_table)
222 		goto out_ipv6_route_table;
223 
224 	net->ipv6.sysctl.hdr = register_net_sysctl(net, "net/ipv6", ipv6_table);
225 	if (!net->ipv6.sysctl.hdr)
226 		goto out_ipv6_icmp_table;
227 
228 	net->ipv6.sysctl.route_hdr =
229 		register_net_sysctl(net, "net/ipv6/route", ipv6_route_table);
230 	if (!net->ipv6.sysctl.route_hdr)
231 		goto out_unregister_ipv6_table;
232 
233 	net->ipv6.sysctl.icmp_hdr =
234 		register_net_sysctl(net, "net/ipv6/icmp", ipv6_icmp_table);
235 	if (!net->ipv6.sysctl.icmp_hdr)
236 		goto out_unregister_route_table;
237 
238 	err = 0;
239 out:
240 	return err;
241 out_unregister_route_table:
242 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
243 out_unregister_ipv6_table:
244 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
245 out_ipv6_icmp_table:
246 	kfree(ipv6_icmp_table);
247 out_ipv6_route_table:
248 	kfree(ipv6_route_table);
249 out_ipv6_table:
250 	kfree(ipv6_table);
251 	goto out;
252 }
253 
254 static void __net_exit ipv6_sysctl_net_exit(struct net *net)
255 {
256 	struct ctl_table *ipv6_table;
257 	struct ctl_table *ipv6_route_table;
258 	struct ctl_table *ipv6_icmp_table;
259 
260 	ipv6_table = net->ipv6.sysctl.hdr->ctl_table_arg;
261 	ipv6_route_table = net->ipv6.sysctl.route_hdr->ctl_table_arg;
262 	ipv6_icmp_table = net->ipv6.sysctl.icmp_hdr->ctl_table_arg;
263 
264 	unregister_net_sysctl_table(net->ipv6.sysctl.icmp_hdr);
265 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
266 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
267 
268 	kfree(ipv6_table);
269 	kfree(ipv6_route_table);
270 	kfree(ipv6_icmp_table);
271 }
272 
273 static struct pernet_operations ipv6_sysctl_net_ops = {
274 	.init = ipv6_sysctl_net_init,
275 	.exit = ipv6_sysctl_net_exit,
276 };
277 
278 static struct ctl_table_header *ip6_header;
279 
280 int ipv6_sysctl_register(void)
281 {
282 	int err = -ENOMEM;
283 
284 	ip6_header = register_net_sysctl(&init_net, "net/ipv6", ipv6_rotable);
285 	if (!ip6_header)
286 		goto out;
287 
288 	err = register_pernet_subsys(&ipv6_sysctl_net_ops);
289 	if (err)
290 		goto err_pernet;
291 out:
292 	return err;
293 
294 err_pernet:
295 	unregister_net_sysctl_table(ip6_header);
296 	goto out;
297 }
298 
299 void ipv6_sysctl_unregister(void)
300 {
301 	unregister_net_sysctl_table(ip6_header);
302 	unregister_pernet_subsys(&ipv6_sysctl_net_ops);
303 }
304