xref: /linux/net/ipv6/sysctl_net_ipv6.c (revision 6c363eafc4d637ac4bd83d4a7dd06dd3cfbe7c5f)
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 two = 2;
25 static int flowlabel_reflect_max = 0x7;
26 static int auto_flowlabels_min;
27 static int auto_flowlabels_max = IP6_AUTO_FLOW_LABEL_MAX;
28 
29 static int proc_rt6_multipath_hash_policy(struct ctl_table *table, int write,
30 					  void *buffer, size_t *lenp, loff_t *ppos)
31 {
32 	struct net *net;
33 	int ret;
34 
35 	net = container_of(table->data, struct net,
36 			   ipv6.sysctl.multipath_hash_policy);
37 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
38 	if (write && ret == 0)
39 		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
40 
41 	return ret;
42 }
43 
44 static struct ctl_table ipv6_table_template[] = {
45 	{
46 		.procname	= "bindv6only",
47 		.data		= &init_net.ipv6.sysctl.bindv6only,
48 		.maxlen		= sizeof(int),
49 		.mode		= 0644,
50 		.proc_handler	= proc_dointvec
51 	},
52 	{
53 		.procname	= "anycast_src_echo_reply",
54 		.data		= &init_net.ipv6.sysctl.anycast_src_echo_reply,
55 		.maxlen		= sizeof(int),
56 		.mode		= 0644,
57 		.proc_handler	= proc_dointvec
58 	},
59 	{
60 		.procname	= "flowlabel_consistency",
61 		.data		= &init_net.ipv6.sysctl.flowlabel_consistency,
62 		.maxlen		= sizeof(int),
63 		.mode		= 0644,
64 		.proc_handler	= proc_dointvec
65 	},
66 	{
67 		.procname	= "auto_flowlabels",
68 		.data		= &init_net.ipv6.sysctl.auto_flowlabels,
69 		.maxlen		= sizeof(int),
70 		.mode		= 0644,
71 		.proc_handler	= proc_dointvec_minmax,
72 		.extra1		= &auto_flowlabels_min,
73 		.extra2		= &auto_flowlabels_max
74 	},
75 	{
76 		.procname	= "fwmark_reflect",
77 		.data		= &init_net.ipv6.sysctl.fwmark_reflect,
78 		.maxlen		= sizeof(int),
79 		.mode		= 0644,
80 		.proc_handler	= proc_dointvec
81 	},
82 	{
83 		.procname	= "idgen_retries",
84 		.data		= &init_net.ipv6.sysctl.idgen_retries,
85 		.maxlen		= sizeof(int),
86 		.mode		= 0644,
87 		.proc_handler	= proc_dointvec,
88 	},
89 	{
90 		.procname	= "idgen_delay",
91 		.data		= &init_net.ipv6.sysctl.idgen_delay,
92 		.maxlen		= sizeof(int),
93 		.mode		= 0644,
94 		.proc_handler	= proc_dointvec_jiffies,
95 	},
96 	{
97 		.procname	= "flowlabel_state_ranges",
98 		.data		= &init_net.ipv6.sysctl.flowlabel_state_ranges,
99 		.maxlen		= sizeof(int),
100 		.mode		= 0644,
101 		.proc_handler	= proc_dointvec
102 	},
103 	{
104 		.procname	= "ip_nonlocal_bind",
105 		.data		= &init_net.ipv6.sysctl.ip_nonlocal_bind,
106 		.maxlen		= sizeof(int),
107 		.mode		= 0644,
108 		.proc_handler	= proc_dointvec
109 	},
110 	{
111 		.procname	= "flowlabel_reflect",
112 		.data		= &init_net.ipv6.sysctl.flowlabel_reflect,
113 		.maxlen		= sizeof(int),
114 		.mode		= 0644,
115 		.proc_handler	= proc_dointvec_minmax,
116 		.extra1		= SYSCTL_ZERO,
117 		.extra2		= &flowlabel_reflect_max,
118 	},
119 	{
120 		.procname	= "max_dst_opts_number",
121 		.data		= &init_net.ipv6.sysctl.max_dst_opts_cnt,
122 		.maxlen		= sizeof(int),
123 		.mode		= 0644,
124 		.proc_handler	= proc_dointvec
125 	},
126 	{
127 		.procname	= "max_hbh_opts_number",
128 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_cnt,
129 		.maxlen		= sizeof(int),
130 		.mode		= 0644,
131 		.proc_handler	= proc_dointvec
132 	},
133 	{
134 		.procname	= "max_dst_opts_length",
135 		.data		= &init_net.ipv6.sysctl.max_dst_opts_len,
136 		.maxlen		= sizeof(int),
137 		.mode		= 0644,
138 		.proc_handler	= proc_dointvec
139 	},
140 	{
141 		.procname	= "max_hbh_length",
142 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_len,
143 		.maxlen		= sizeof(int),
144 		.mode		= 0644,
145 		.proc_handler	= proc_dointvec
146 	},
147 	{
148 		.procname	= "fib_multipath_hash_policy",
149 		.data		= &init_net.ipv6.sysctl.multipath_hash_policy,
150 		.maxlen		= sizeof(int),
151 		.mode		= 0644,
152 		.proc_handler   = proc_rt6_multipath_hash_policy,
153 		.extra1		= SYSCTL_ZERO,
154 		.extra2		= &two,
155 	},
156 	{
157 		.procname	= "seg6_flowlabel",
158 		.data		= &init_net.ipv6.sysctl.seg6_flowlabel,
159 		.maxlen		= sizeof(int),
160 		.mode		= 0644,
161 		.proc_handler	= proc_dointvec
162 	},
163 	{
164 		.procname	= "fib_notify_on_flag_change",
165 		.data		= &init_net.ipv6.sysctl.fib_notify_on_flag_change,
166 		.maxlen		= sizeof(int),
167 		.mode		= 0644,
168 		.proc_handler	= proc_dointvec_minmax,
169 		.extra1         = SYSCTL_ZERO,
170 		.extra2         = &two,
171 	},
172 	{ }
173 };
174 
175 static struct ctl_table ipv6_rotable[] = {
176 	{
177 		.procname	= "mld_max_msf",
178 		.data		= &sysctl_mld_max_msf,
179 		.maxlen		= sizeof(int),
180 		.mode		= 0644,
181 		.proc_handler	= proc_dointvec
182 	},
183 	{
184 		.procname	= "mld_qrv",
185 		.data		= &sysctl_mld_qrv,
186 		.maxlen		= sizeof(int),
187 		.mode		= 0644,
188 		.proc_handler	= proc_dointvec_minmax,
189 		.extra1		= SYSCTL_ONE
190 	},
191 #ifdef CONFIG_NETLABEL
192 	{
193 		.procname	= "calipso_cache_enable",
194 		.data		= &calipso_cache_enabled,
195 		.maxlen		= sizeof(int),
196 		.mode		= 0644,
197 		.proc_handler	= proc_dointvec,
198 	},
199 	{
200 		.procname	= "calipso_cache_bucket_size",
201 		.data		= &calipso_cache_bucketsize,
202 		.maxlen		= sizeof(int),
203 		.mode		= 0644,
204 		.proc_handler	= proc_dointvec,
205 	},
206 #endif /* CONFIG_NETLABEL */
207 	{ }
208 };
209 
210 static int __net_init ipv6_sysctl_net_init(struct net *net)
211 {
212 	struct ctl_table *ipv6_table;
213 	struct ctl_table *ipv6_route_table;
214 	struct ctl_table *ipv6_icmp_table;
215 	int err, i;
216 
217 	err = -ENOMEM;
218 	ipv6_table = kmemdup(ipv6_table_template, sizeof(ipv6_table_template),
219 			     GFP_KERNEL);
220 	if (!ipv6_table)
221 		goto out;
222 	/* Update the variables to point into the current struct net */
223 	for (i = 0; i < ARRAY_SIZE(ipv6_table_template) - 1; i++)
224 		ipv6_table[i].data += (void *)net - (void *)&init_net;
225 
226 	ipv6_route_table = ipv6_route_sysctl_init(net);
227 	if (!ipv6_route_table)
228 		goto out_ipv6_table;
229 
230 	ipv6_icmp_table = ipv6_icmp_sysctl_init(net);
231 	if (!ipv6_icmp_table)
232 		goto out_ipv6_route_table;
233 
234 	net->ipv6.sysctl.hdr = register_net_sysctl(net, "net/ipv6", ipv6_table);
235 	if (!net->ipv6.sysctl.hdr)
236 		goto out_ipv6_icmp_table;
237 
238 	net->ipv6.sysctl.route_hdr =
239 		register_net_sysctl(net, "net/ipv6/route", ipv6_route_table);
240 	if (!net->ipv6.sysctl.route_hdr)
241 		goto out_unregister_ipv6_table;
242 
243 	net->ipv6.sysctl.icmp_hdr =
244 		register_net_sysctl(net, "net/ipv6/icmp", ipv6_icmp_table);
245 	if (!net->ipv6.sysctl.icmp_hdr)
246 		goto out_unregister_route_table;
247 
248 	err = 0;
249 out:
250 	return err;
251 out_unregister_route_table:
252 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
253 out_unregister_ipv6_table:
254 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
255 out_ipv6_icmp_table:
256 	kfree(ipv6_icmp_table);
257 out_ipv6_route_table:
258 	kfree(ipv6_route_table);
259 out_ipv6_table:
260 	kfree(ipv6_table);
261 	goto out;
262 }
263 
264 static void __net_exit ipv6_sysctl_net_exit(struct net *net)
265 {
266 	struct ctl_table *ipv6_table;
267 	struct ctl_table *ipv6_route_table;
268 	struct ctl_table *ipv6_icmp_table;
269 
270 	ipv6_table = net->ipv6.sysctl.hdr->ctl_table_arg;
271 	ipv6_route_table = net->ipv6.sysctl.route_hdr->ctl_table_arg;
272 	ipv6_icmp_table = net->ipv6.sysctl.icmp_hdr->ctl_table_arg;
273 
274 	unregister_net_sysctl_table(net->ipv6.sysctl.icmp_hdr);
275 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
276 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
277 
278 	kfree(ipv6_table);
279 	kfree(ipv6_route_table);
280 	kfree(ipv6_icmp_table);
281 }
282 
283 static struct pernet_operations ipv6_sysctl_net_ops = {
284 	.init = ipv6_sysctl_net_init,
285 	.exit = ipv6_sysctl_net_exit,
286 };
287 
288 static struct ctl_table_header *ip6_header;
289 
290 int ipv6_sysctl_register(void)
291 {
292 	int err = -ENOMEM;
293 
294 	ip6_header = register_net_sysctl(&init_net, "net/ipv6", ipv6_rotable);
295 	if (!ip6_header)
296 		goto out;
297 
298 	err = register_pernet_subsys(&ipv6_sysctl_net_ops);
299 	if (err)
300 		goto err_pernet;
301 out:
302 	return err;
303 
304 err_pernet:
305 	unregister_net_sysctl_table(ip6_header);
306 	goto out;
307 }
308 
309 void ipv6_sysctl_unregister(void)
310 {
311 	unregister_net_sysctl_table(ip6_header);
312 	unregister_pernet_subsys(&ipv6_sysctl_net_ops);
313 }
314