xref: /linux/net/ipv6/sysctl_net_ipv6.c (revision 3f0a50f345f78183f6e9b39c2f45ca5dcaa511ca)
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 #include <linux/ioam6.h>
25 
26 static int two = 2;
27 static int three = 3;
28 static int flowlabel_reflect_max = 0x7;
29 static int auto_flowlabels_max = IP6_AUTO_FLOW_LABEL_MAX;
30 static u32 rt6_multipath_hash_fields_all_mask =
31 	FIB_MULTIPATH_HASH_FIELD_ALL_MASK;
32 static u32 ioam6_id_max = IOAM6_DEFAULT_ID;
33 static u64 ioam6_id_wide_max = IOAM6_DEFAULT_ID_WIDE;
34 
35 static int proc_rt6_multipath_hash_policy(struct ctl_table *table, int write,
36 					  void *buffer, size_t *lenp, loff_t *ppos)
37 {
38 	struct net *net;
39 	int ret;
40 
41 	net = container_of(table->data, struct net,
42 			   ipv6.sysctl.multipath_hash_policy);
43 	ret = proc_dou8vec_minmax(table, write, buffer, lenp, ppos);
44 	if (write && ret == 0)
45 		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
46 
47 	return ret;
48 }
49 
50 static int
51 proc_rt6_multipath_hash_fields(struct ctl_table *table, int write, void *buffer,
52 			       size_t *lenp, loff_t *ppos)
53 {
54 	struct net *net;
55 	int ret;
56 
57 	net = container_of(table->data, struct net,
58 			   ipv6.sysctl.multipath_hash_fields);
59 	ret = proc_douintvec_minmax(table, write, buffer, lenp, ppos);
60 	if (write && ret == 0)
61 		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
62 
63 	return ret;
64 }
65 
66 static struct ctl_table ipv6_table_template[] = {
67 	{
68 		.procname	= "bindv6only",
69 		.data		= &init_net.ipv6.sysctl.bindv6only,
70 		.maxlen		= sizeof(u8),
71 		.mode		= 0644,
72 		.proc_handler	= proc_dou8vec_minmax,
73 	},
74 	{
75 		.procname	= "anycast_src_echo_reply",
76 		.data		= &init_net.ipv6.sysctl.anycast_src_echo_reply,
77 		.maxlen		= sizeof(u8),
78 		.mode		= 0644,
79 		.proc_handler	= proc_dou8vec_minmax,
80 	},
81 	{
82 		.procname	= "flowlabel_consistency",
83 		.data		= &init_net.ipv6.sysctl.flowlabel_consistency,
84 		.maxlen		= sizeof(u8),
85 		.mode		= 0644,
86 		.proc_handler	= proc_dou8vec_minmax,
87 	},
88 	{
89 		.procname	= "auto_flowlabels",
90 		.data		= &init_net.ipv6.sysctl.auto_flowlabels,
91 		.maxlen		= sizeof(u8),
92 		.mode		= 0644,
93 		.proc_handler	= proc_dou8vec_minmax,
94 		.extra2		= &auto_flowlabels_max
95 	},
96 	{
97 		.procname	= "fwmark_reflect",
98 		.data		= &init_net.ipv6.sysctl.fwmark_reflect,
99 		.maxlen		= sizeof(u8),
100 		.mode		= 0644,
101 		.proc_handler	= proc_dou8vec_minmax,
102 	},
103 	{
104 		.procname	= "idgen_retries",
105 		.data		= &init_net.ipv6.sysctl.idgen_retries,
106 		.maxlen		= sizeof(int),
107 		.mode		= 0644,
108 		.proc_handler	= proc_dointvec,
109 	},
110 	{
111 		.procname	= "idgen_delay",
112 		.data		= &init_net.ipv6.sysctl.idgen_delay,
113 		.maxlen		= sizeof(int),
114 		.mode		= 0644,
115 		.proc_handler	= proc_dointvec_jiffies,
116 	},
117 	{
118 		.procname	= "flowlabel_state_ranges",
119 		.data		= &init_net.ipv6.sysctl.flowlabel_state_ranges,
120 		.maxlen		= sizeof(u8),
121 		.mode		= 0644,
122 		.proc_handler	= proc_dou8vec_minmax,
123 	},
124 	{
125 		.procname	= "ip_nonlocal_bind",
126 		.data		= &init_net.ipv6.sysctl.ip_nonlocal_bind,
127 		.maxlen		= sizeof(u8),
128 		.mode		= 0644,
129 		.proc_handler	= proc_dou8vec_minmax,
130 	},
131 	{
132 		.procname	= "flowlabel_reflect",
133 		.data		= &init_net.ipv6.sysctl.flowlabel_reflect,
134 		.maxlen		= sizeof(int),
135 		.mode		= 0644,
136 		.proc_handler	= proc_dointvec_minmax,
137 		.extra1		= SYSCTL_ZERO,
138 		.extra2		= &flowlabel_reflect_max,
139 	},
140 	{
141 		.procname	= "max_dst_opts_number",
142 		.data		= &init_net.ipv6.sysctl.max_dst_opts_cnt,
143 		.maxlen		= sizeof(int),
144 		.mode		= 0644,
145 		.proc_handler	= proc_dointvec
146 	},
147 	{
148 		.procname	= "max_hbh_opts_number",
149 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_cnt,
150 		.maxlen		= sizeof(int),
151 		.mode		= 0644,
152 		.proc_handler	= proc_dointvec
153 	},
154 	{
155 		.procname	= "max_dst_opts_length",
156 		.data		= &init_net.ipv6.sysctl.max_dst_opts_len,
157 		.maxlen		= sizeof(int),
158 		.mode		= 0644,
159 		.proc_handler	= proc_dointvec
160 	},
161 	{
162 		.procname	= "max_hbh_length",
163 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_len,
164 		.maxlen		= sizeof(int),
165 		.mode		= 0644,
166 		.proc_handler	= proc_dointvec
167 	},
168 	{
169 		.procname	= "fib_multipath_hash_policy",
170 		.data		= &init_net.ipv6.sysctl.multipath_hash_policy,
171 		.maxlen		= sizeof(u8),
172 		.mode		= 0644,
173 		.proc_handler   = proc_rt6_multipath_hash_policy,
174 		.extra1		= SYSCTL_ZERO,
175 		.extra2		= &three,
176 	},
177 	{
178 		.procname	= "fib_multipath_hash_fields",
179 		.data		= &init_net.ipv6.sysctl.multipath_hash_fields,
180 		.maxlen		= sizeof(u32),
181 		.mode		= 0644,
182 		.proc_handler	= proc_rt6_multipath_hash_fields,
183 		.extra1		= SYSCTL_ONE,
184 		.extra2		= &rt6_multipath_hash_fields_all_mask,
185 	},
186 	{
187 		.procname	= "seg6_flowlabel",
188 		.data		= &init_net.ipv6.sysctl.seg6_flowlabel,
189 		.maxlen		= sizeof(int),
190 		.mode		= 0644,
191 		.proc_handler	= proc_dointvec
192 	},
193 	{
194 		.procname	= "fib_notify_on_flag_change",
195 		.data		= &init_net.ipv6.sysctl.fib_notify_on_flag_change,
196 		.maxlen		= sizeof(u8),
197 		.mode		= 0644,
198 		.proc_handler	= proc_dou8vec_minmax,
199 		.extra1         = SYSCTL_ZERO,
200 		.extra2         = &two,
201 	},
202 	{
203 		.procname	= "ioam6_id",
204 		.data		= &init_net.ipv6.sysctl.ioam6_id,
205 		.maxlen		= sizeof(u32),
206 		.mode		= 0644,
207 		.proc_handler	= proc_douintvec_minmax,
208 		.extra2		= &ioam6_id_max,
209 	},
210 	{
211 		.procname	= "ioam6_id_wide",
212 		.data		= &init_net.ipv6.sysctl.ioam6_id_wide,
213 		.maxlen		= sizeof(u64),
214 		.mode		= 0644,
215 		.proc_handler	= proc_doulongvec_minmax,
216 		.extra2		= &ioam6_id_wide_max,
217 	},
218 	{ }
219 };
220 
221 static struct ctl_table ipv6_rotable[] = {
222 	{
223 		.procname	= "mld_max_msf",
224 		.data		= &sysctl_mld_max_msf,
225 		.maxlen		= sizeof(int),
226 		.mode		= 0644,
227 		.proc_handler	= proc_dointvec
228 	},
229 	{
230 		.procname	= "mld_qrv",
231 		.data		= &sysctl_mld_qrv,
232 		.maxlen		= sizeof(int),
233 		.mode		= 0644,
234 		.proc_handler	= proc_dointvec_minmax,
235 		.extra1		= SYSCTL_ONE
236 	},
237 #ifdef CONFIG_NETLABEL
238 	{
239 		.procname	= "calipso_cache_enable",
240 		.data		= &calipso_cache_enabled,
241 		.maxlen		= sizeof(int),
242 		.mode		= 0644,
243 		.proc_handler	= proc_dointvec,
244 	},
245 	{
246 		.procname	= "calipso_cache_bucket_size",
247 		.data		= &calipso_cache_bucketsize,
248 		.maxlen		= sizeof(int),
249 		.mode		= 0644,
250 		.proc_handler	= proc_dointvec,
251 	},
252 #endif /* CONFIG_NETLABEL */
253 	{ }
254 };
255 
256 static int __net_init ipv6_sysctl_net_init(struct net *net)
257 {
258 	struct ctl_table *ipv6_table;
259 	struct ctl_table *ipv6_route_table;
260 	struct ctl_table *ipv6_icmp_table;
261 	int err, i;
262 
263 	err = -ENOMEM;
264 	ipv6_table = kmemdup(ipv6_table_template, sizeof(ipv6_table_template),
265 			     GFP_KERNEL);
266 	if (!ipv6_table)
267 		goto out;
268 	/* Update the variables to point into the current struct net */
269 	for (i = 0; i < ARRAY_SIZE(ipv6_table_template) - 1; i++)
270 		ipv6_table[i].data += (void *)net - (void *)&init_net;
271 
272 	ipv6_route_table = ipv6_route_sysctl_init(net);
273 	if (!ipv6_route_table)
274 		goto out_ipv6_table;
275 
276 	ipv6_icmp_table = ipv6_icmp_sysctl_init(net);
277 	if (!ipv6_icmp_table)
278 		goto out_ipv6_route_table;
279 
280 	net->ipv6.sysctl.hdr = register_net_sysctl(net, "net/ipv6", ipv6_table);
281 	if (!net->ipv6.sysctl.hdr)
282 		goto out_ipv6_icmp_table;
283 
284 	net->ipv6.sysctl.route_hdr =
285 		register_net_sysctl(net, "net/ipv6/route", ipv6_route_table);
286 	if (!net->ipv6.sysctl.route_hdr)
287 		goto out_unregister_ipv6_table;
288 
289 	net->ipv6.sysctl.icmp_hdr =
290 		register_net_sysctl(net, "net/ipv6/icmp", ipv6_icmp_table);
291 	if (!net->ipv6.sysctl.icmp_hdr)
292 		goto out_unregister_route_table;
293 
294 	err = 0;
295 out:
296 	return err;
297 out_unregister_route_table:
298 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
299 out_unregister_ipv6_table:
300 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
301 out_ipv6_icmp_table:
302 	kfree(ipv6_icmp_table);
303 out_ipv6_route_table:
304 	kfree(ipv6_route_table);
305 out_ipv6_table:
306 	kfree(ipv6_table);
307 	goto out;
308 }
309 
310 static void __net_exit ipv6_sysctl_net_exit(struct net *net)
311 {
312 	struct ctl_table *ipv6_table;
313 	struct ctl_table *ipv6_route_table;
314 	struct ctl_table *ipv6_icmp_table;
315 
316 	ipv6_table = net->ipv6.sysctl.hdr->ctl_table_arg;
317 	ipv6_route_table = net->ipv6.sysctl.route_hdr->ctl_table_arg;
318 	ipv6_icmp_table = net->ipv6.sysctl.icmp_hdr->ctl_table_arg;
319 
320 	unregister_net_sysctl_table(net->ipv6.sysctl.icmp_hdr);
321 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
322 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
323 
324 	kfree(ipv6_table);
325 	kfree(ipv6_route_table);
326 	kfree(ipv6_icmp_table);
327 }
328 
329 static struct pernet_operations ipv6_sysctl_net_ops = {
330 	.init = ipv6_sysctl_net_init,
331 	.exit = ipv6_sysctl_net_exit,
332 };
333 
334 static struct ctl_table_header *ip6_header;
335 
336 int ipv6_sysctl_register(void)
337 {
338 	int err = -ENOMEM;
339 
340 	ip6_header = register_net_sysctl(&init_net, "net/ipv6", ipv6_rotable);
341 	if (!ip6_header)
342 		goto out;
343 
344 	err = register_pernet_subsys(&ipv6_sysctl_net_ops);
345 	if (err)
346 		goto err_pernet;
347 out:
348 	return err;
349 
350 err_pernet:
351 	unregister_net_sysctl_table(ip6_header);
352 	goto out;
353 }
354 
355 void ipv6_sysctl_unregister(void)
356 {
357 	unregister_net_sysctl_table(ip6_header);
358 	unregister_pernet_subsys(&ipv6_sysctl_net_ops);
359 }
360