xref: /linux/net/ipv6/sysctl_net_ipv6.c (revision 39f75da7bcc829ddc4d40bb60d0e95520de7898b)
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 #include <net/ip_fib.h>
21 #ifdef CONFIG_NETLABEL
22 #include <net/calipso.h>
23 #endif
24 
25 static int two = 2;
26 static int three = 3;
27 static int flowlabel_reflect_max = 0x7;
28 static int auto_flowlabels_max = IP6_AUTO_FLOW_LABEL_MAX;
29 static u32 rt6_multipath_hash_fields_all_mask =
30 	FIB_MULTIPATH_HASH_FIELD_ALL_MASK;
31 
32 static int proc_rt6_multipath_hash_policy(struct ctl_table *table, int write,
33 					  void *buffer, size_t *lenp, loff_t *ppos)
34 {
35 	struct net *net;
36 	int ret;
37 
38 	net = container_of(table->data, struct net,
39 			   ipv6.sysctl.multipath_hash_policy);
40 	ret = proc_dou8vec_minmax(table, write, buffer, lenp, ppos);
41 	if (write && ret == 0)
42 		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
43 
44 	return ret;
45 }
46 
47 static int
48 proc_rt6_multipath_hash_fields(struct ctl_table *table, int write, void *buffer,
49 			       size_t *lenp, loff_t *ppos)
50 {
51 	struct net *net;
52 	int ret;
53 
54 	net = container_of(table->data, struct net,
55 			   ipv6.sysctl.multipath_hash_fields);
56 	ret = proc_douintvec_minmax(table, write, buffer, lenp, ppos);
57 	if (write && ret == 0)
58 		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
59 
60 	return ret;
61 }
62 
63 static struct ctl_table ipv6_table_template[] = {
64 	{
65 		.procname	= "bindv6only",
66 		.data		= &init_net.ipv6.sysctl.bindv6only,
67 		.maxlen		= sizeof(u8),
68 		.mode		= 0644,
69 		.proc_handler	= proc_dou8vec_minmax,
70 	},
71 	{
72 		.procname	= "anycast_src_echo_reply",
73 		.data		= &init_net.ipv6.sysctl.anycast_src_echo_reply,
74 		.maxlen		= sizeof(u8),
75 		.mode		= 0644,
76 		.proc_handler	= proc_dou8vec_minmax,
77 	},
78 	{
79 		.procname	= "flowlabel_consistency",
80 		.data		= &init_net.ipv6.sysctl.flowlabel_consistency,
81 		.maxlen		= sizeof(u8),
82 		.mode		= 0644,
83 		.proc_handler	= proc_dou8vec_minmax,
84 	},
85 	{
86 		.procname	= "auto_flowlabels",
87 		.data		= &init_net.ipv6.sysctl.auto_flowlabels,
88 		.maxlen		= sizeof(u8),
89 		.mode		= 0644,
90 		.proc_handler	= proc_dou8vec_minmax,
91 		.extra2		= &auto_flowlabels_max
92 	},
93 	{
94 		.procname	= "fwmark_reflect",
95 		.data		= &init_net.ipv6.sysctl.fwmark_reflect,
96 		.maxlen		= sizeof(u8),
97 		.mode		= 0644,
98 		.proc_handler	= proc_dou8vec_minmax,
99 	},
100 	{
101 		.procname	= "idgen_retries",
102 		.data		= &init_net.ipv6.sysctl.idgen_retries,
103 		.maxlen		= sizeof(int),
104 		.mode		= 0644,
105 		.proc_handler	= proc_dointvec,
106 	},
107 	{
108 		.procname	= "idgen_delay",
109 		.data		= &init_net.ipv6.sysctl.idgen_delay,
110 		.maxlen		= sizeof(int),
111 		.mode		= 0644,
112 		.proc_handler	= proc_dointvec_jiffies,
113 	},
114 	{
115 		.procname	= "flowlabel_state_ranges",
116 		.data		= &init_net.ipv6.sysctl.flowlabel_state_ranges,
117 		.maxlen		= sizeof(u8),
118 		.mode		= 0644,
119 		.proc_handler	= proc_dou8vec_minmax,
120 	},
121 	{
122 		.procname	= "ip_nonlocal_bind",
123 		.data		= &init_net.ipv6.sysctl.ip_nonlocal_bind,
124 		.maxlen		= sizeof(u8),
125 		.mode		= 0644,
126 		.proc_handler	= proc_dou8vec_minmax,
127 	},
128 	{
129 		.procname	= "flowlabel_reflect",
130 		.data		= &init_net.ipv6.sysctl.flowlabel_reflect,
131 		.maxlen		= sizeof(int),
132 		.mode		= 0644,
133 		.proc_handler	= proc_dointvec_minmax,
134 		.extra1		= SYSCTL_ZERO,
135 		.extra2		= &flowlabel_reflect_max,
136 	},
137 	{
138 		.procname	= "max_dst_opts_number",
139 		.data		= &init_net.ipv6.sysctl.max_dst_opts_cnt,
140 		.maxlen		= sizeof(int),
141 		.mode		= 0644,
142 		.proc_handler	= proc_dointvec
143 	},
144 	{
145 		.procname	= "max_hbh_opts_number",
146 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_cnt,
147 		.maxlen		= sizeof(int),
148 		.mode		= 0644,
149 		.proc_handler	= proc_dointvec
150 	},
151 	{
152 		.procname	= "max_dst_opts_length",
153 		.data		= &init_net.ipv6.sysctl.max_dst_opts_len,
154 		.maxlen		= sizeof(int),
155 		.mode		= 0644,
156 		.proc_handler	= proc_dointvec
157 	},
158 	{
159 		.procname	= "max_hbh_length",
160 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_len,
161 		.maxlen		= sizeof(int),
162 		.mode		= 0644,
163 		.proc_handler	= proc_dointvec
164 	},
165 	{
166 		.procname	= "fib_multipath_hash_policy",
167 		.data		= &init_net.ipv6.sysctl.multipath_hash_policy,
168 		.maxlen		= sizeof(u8),
169 		.mode		= 0644,
170 		.proc_handler   = proc_rt6_multipath_hash_policy,
171 		.extra1		= SYSCTL_ZERO,
172 		.extra2		= &three,
173 	},
174 	{
175 		.procname	= "fib_multipath_hash_fields",
176 		.data		= &init_net.ipv6.sysctl.multipath_hash_fields,
177 		.maxlen		= sizeof(u32),
178 		.mode		= 0644,
179 		.proc_handler	= proc_rt6_multipath_hash_fields,
180 		.extra1		= SYSCTL_ONE,
181 		.extra2		= &rt6_multipath_hash_fields_all_mask,
182 	},
183 	{
184 		.procname	= "seg6_flowlabel",
185 		.data		= &init_net.ipv6.sysctl.seg6_flowlabel,
186 		.maxlen		= sizeof(int),
187 		.mode		= 0644,
188 		.proc_handler	= proc_dointvec
189 	},
190 	{
191 		.procname	= "fib_notify_on_flag_change",
192 		.data		= &init_net.ipv6.sysctl.fib_notify_on_flag_change,
193 		.maxlen		= sizeof(u8),
194 		.mode		= 0644,
195 		.proc_handler	= proc_dou8vec_minmax,
196 		.extra1         = SYSCTL_ZERO,
197 		.extra2         = &two,
198 	},
199 	{ }
200 };
201 
202 static struct ctl_table ipv6_rotable[] = {
203 	{
204 		.procname	= "mld_max_msf",
205 		.data		= &sysctl_mld_max_msf,
206 		.maxlen		= sizeof(int),
207 		.mode		= 0644,
208 		.proc_handler	= proc_dointvec
209 	},
210 	{
211 		.procname	= "mld_qrv",
212 		.data		= &sysctl_mld_qrv,
213 		.maxlen		= sizeof(int),
214 		.mode		= 0644,
215 		.proc_handler	= proc_dointvec_minmax,
216 		.extra1		= SYSCTL_ONE
217 	},
218 #ifdef CONFIG_NETLABEL
219 	{
220 		.procname	= "calipso_cache_enable",
221 		.data		= &calipso_cache_enabled,
222 		.maxlen		= sizeof(int),
223 		.mode		= 0644,
224 		.proc_handler	= proc_dointvec,
225 	},
226 	{
227 		.procname	= "calipso_cache_bucket_size",
228 		.data		= &calipso_cache_bucketsize,
229 		.maxlen		= sizeof(int),
230 		.mode		= 0644,
231 		.proc_handler	= proc_dointvec,
232 	},
233 #endif /* CONFIG_NETLABEL */
234 	{ }
235 };
236 
237 static int __net_init ipv6_sysctl_net_init(struct net *net)
238 {
239 	struct ctl_table *ipv6_table;
240 	struct ctl_table *ipv6_route_table;
241 	struct ctl_table *ipv6_icmp_table;
242 	int err, i;
243 
244 	err = -ENOMEM;
245 	ipv6_table = kmemdup(ipv6_table_template, sizeof(ipv6_table_template),
246 			     GFP_KERNEL);
247 	if (!ipv6_table)
248 		goto out;
249 	/* Update the variables to point into the current struct net */
250 	for (i = 0; i < ARRAY_SIZE(ipv6_table_template) - 1; i++)
251 		ipv6_table[i].data += (void *)net - (void *)&init_net;
252 
253 	ipv6_route_table = ipv6_route_sysctl_init(net);
254 	if (!ipv6_route_table)
255 		goto out_ipv6_table;
256 
257 	ipv6_icmp_table = ipv6_icmp_sysctl_init(net);
258 	if (!ipv6_icmp_table)
259 		goto out_ipv6_route_table;
260 
261 	net->ipv6.sysctl.hdr = register_net_sysctl(net, "net/ipv6", ipv6_table);
262 	if (!net->ipv6.sysctl.hdr)
263 		goto out_ipv6_icmp_table;
264 
265 	net->ipv6.sysctl.route_hdr =
266 		register_net_sysctl(net, "net/ipv6/route", ipv6_route_table);
267 	if (!net->ipv6.sysctl.route_hdr)
268 		goto out_unregister_ipv6_table;
269 
270 	net->ipv6.sysctl.icmp_hdr =
271 		register_net_sysctl(net, "net/ipv6/icmp", ipv6_icmp_table);
272 	if (!net->ipv6.sysctl.icmp_hdr)
273 		goto out_unregister_route_table;
274 
275 	err = 0;
276 out:
277 	return err;
278 out_unregister_route_table:
279 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
280 out_unregister_ipv6_table:
281 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
282 out_ipv6_icmp_table:
283 	kfree(ipv6_icmp_table);
284 out_ipv6_route_table:
285 	kfree(ipv6_route_table);
286 out_ipv6_table:
287 	kfree(ipv6_table);
288 	goto out;
289 }
290 
291 static void __net_exit ipv6_sysctl_net_exit(struct net *net)
292 {
293 	struct ctl_table *ipv6_table;
294 	struct ctl_table *ipv6_route_table;
295 	struct ctl_table *ipv6_icmp_table;
296 
297 	ipv6_table = net->ipv6.sysctl.hdr->ctl_table_arg;
298 	ipv6_route_table = net->ipv6.sysctl.route_hdr->ctl_table_arg;
299 	ipv6_icmp_table = net->ipv6.sysctl.icmp_hdr->ctl_table_arg;
300 
301 	unregister_net_sysctl_table(net->ipv6.sysctl.icmp_hdr);
302 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
303 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
304 
305 	kfree(ipv6_table);
306 	kfree(ipv6_route_table);
307 	kfree(ipv6_icmp_table);
308 }
309 
310 static struct pernet_operations ipv6_sysctl_net_ops = {
311 	.init = ipv6_sysctl_net_init,
312 	.exit = ipv6_sysctl_net_exit,
313 };
314 
315 static struct ctl_table_header *ip6_header;
316 
317 int ipv6_sysctl_register(void)
318 {
319 	int err = -ENOMEM;
320 
321 	ip6_header = register_net_sysctl(&init_net, "net/ipv6", ipv6_rotable);
322 	if (!ip6_header)
323 		goto out;
324 
325 	err = register_pernet_subsys(&ipv6_sysctl_net_ops);
326 	if (err)
327 		goto err_pernet;
328 out:
329 	return err;
330 
331 err_pernet:
332 	unregister_net_sysctl_table(ip6_header);
333 	goto out;
334 }
335 
336 void ipv6_sysctl_unregister(void)
337 {
338 	unregister_net_sysctl_table(ip6_header);
339 	unregister_pernet_subsys(&ipv6_sysctl_net_ops);
340 }
341