xref: /linux/net/ipv6/sysctl_net_ipv6.c (revision cf21f328fcafacf4f96e7a30ef9dceede1076378)
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 flowlabel_reflect_max = 0x7;
27 static int auto_flowlabels_max = IP6_AUTO_FLOW_LABEL_MAX;
28 static u32 rt6_multipath_hash_fields_all_mask =
29 	FIB_MULTIPATH_HASH_FIELD_ALL_MASK;
30 static u32 ioam6_id_max = IOAM6_DEFAULT_ID;
31 static u64 ioam6_id_wide_max = IOAM6_DEFAULT_ID_WIDE;
32 
33 static int proc_rt6_multipath_hash_policy(struct ctl_table *table, int write,
34 					  void *buffer, size_t *lenp, loff_t *ppos)
35 {
36 	struct net *net;
37 	int ret;
38 
39 	net = container_of(table->data, struct net,
40 			   ipv6.sysctl.multipath_hash_policy);
41 	ret = proc_dou8vec_minmax(table, write, buffer, lenp, ppos);
42 	if (write && ret == 0)
43 		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
44 
45 	return ret;
46 }
47 
48 static int
49 proc_rt6_multipath_hash_fields(struct ctl_table *table, int write, void *buffer,
50 			       size_t *lenp, loff_t *ppos)
51 {
52 	struct net *net;
53 	int ret;
54 
55 	net = container_of(table->data, struct net,
56 			   ipv6.sysctl.multipath_hash_fields);
57 	ret = proc_douintvec_minmax(table, write, buffer, lenp, ppos);
58 	if (write && ret == 0)
59 		call_netevent_notifiers(NETEVENT_IPV6_MPATH_HASH_UPDATE, net);
60 
61 	return ret;
62 }
63 
64 static struct ctl_table ipv6_table_template[] = {
65 	{
66 		.procname	= "bindv6only",
67 		.data		= &init_net.ipv6.sysctl.bindv6only,
68 		.maxlen		= sizeof(u8),
69 		.mode		= 0644,
70 		.proc_handler	= proc_dou8vec_minmax,
71 	},
72 	{
73 		.procname	= "anycast_src_echo_reply",
74 		.data		= &init_net.ipv6.sysctl.anycast_src_echo_reply,
75 		.maxlen		= sizeof(u8),
76 		.mode		= 0644,
77 		.proc_handler	= proc_dou8vec_minmax,
78 	},
79 	{
80 		.procname	= "flowlabel_consistency",
81 		.data		= &init_net.ipv6.sysctl.flowlabel_consistency,
82 		.maxlen		= sizeof(u8),
83 		.mode		= 0644,
84 		.proc_handler	= proc_dou8vec_minmax,
85 	},
86 	{
87 		.procname	= "auto_flowlabels",
88 		.data		= &init_net.ipv6.sysctl.auto_flowlabels,
89 		.maxlen		= sizeof(u8),
90 		.mode		= 0644,
91 		.proc_handler	= proc_dou8vec_minmax,
92 		.extra2		= &auto_flowlabels_max
93 	},
94 	{
95 		.procname	= "fwmark_reflect",
96 		.data		= &init_net.ipv6.sysctl.fwmark_reflect,
97 		.maxlen		= sizeof(u8),
98 		.mode		= 0644,
99 		.proc_handler	= proc_dou8vec_minmax,
100 	},
101 	{
102 		.procname	= "idgen_retries",
103 		.data		= &init_net.ipv6.sysctl.idgen_retries,
104 		.maxlen		= sizeof(int),
105 		.mode		= 0644,
106 		.proc_handler	= proc_dointvec,
107 	},
108 	{
109 		.procname	= "idgen_delay",
110 		.data		= &init_net.ipv6.sysctl.idgen_delay,
111 		.maxlen		= sizeof(int),
112 		.mode		= 0644,
113 		.proc_handler	= proc_dointvec_jiffies,
114 	},
115 	{
116 		.procname	= "flowlabel_state_ranges",
117 		.data		= &init_net.ipv6.sysctl.flowlabel_state_ranges,
118 		.maxlen		= sizeof(u8),
119 		.mode		= 0644,
120 		.proc_handler	= proc_dou8vec_minmax,
121 	},
122 	{
123 		.procname	= "ip_nonlocal_bind",
124 		.data		= &init_net.ipv6.sysctl.ip_nonlocal_bind,
125 		.maxlen		= sizeof(u8),
126 		.mode		= 0644,
127 		.proc_handler	= proc_dou8vec_minmax,
128 	},
129 	{
130 		.procname	= "flowlabel_reflect",
131 		.data		= &init_net.ipv6.sysctl.flowlabel_reflect,
132 		.maxlen		= sizeof(int),
133 		.mode		= 0644,
134 		.proc_handler	= proc_dointvec_minmax,
135 		.extra1		= SYSCTL_ZERO,
136 		.extra2		= &flowlabel_reflect_max,
137 	},
138 	{
139 		.procname	= "max_dst_opts_number",
140 		.data		= &init_net.ipv6.sysctl.max_dst_opts_cnt,
141 		.maxlen		= sizeof(int),
142 		.mode		= 0644,
143 		.proc_handler	= proc_dointvec
144 	},
145 	{
146 		.procname	= "max_hbh_opts_number",
147 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_cnt,
148 		.maxlen		= sizeof(int),
149 		.mode		= 0644,
150 		.proc_handler	= proc_dointvec
151 	},
152 	{
153 		.procname	= "max_dst_opts_length",
154 		.data		= &init_net.ipv6.sysctl.max_dst_opts_len,
155 		.maxlen		= sizeof(int),
156 		.mode		= 0644,
157 		.proc_handler	= proc_dointvec
158 	},
159 	{
160 		.procname	= "max_hbh_length",
161 		.data		= &init_net.ipv6.sysctl.max_hbh_opts_len,
162 		.maxlen		= sizeof(int),
163 		.mode		= 0644,
164 		.proc_handler	= proc_dointvec
165 	},
166 	{
167 		.procname	= "fib_multipath_hash_policy",
168 		.data		= &init_net.ipv6.sysctl.multipath_hash_policy,
169 		.maxlen		= sizeof(u8),
170 		.mode		= 0644,
171 		.proc_handler   = proc_rt6_multipath_hash_policy,
172 		.extra1		= SYSCTL_ZERO,
173 		.extra2		= SYSCTL_THREE,
174 	},
175 	{
176 		.procname	= "fib_multipath_hash_fields",
177 		.data		= &init_net.ipv6.sysctl.multipath_hash_fields,
178 		.maxlen		= sizeof(u32),
179 		.mode		= 0644,
180 		.proc_handler	= proc_rt6_multipath_hash_fields,
181 		.extra1		= SYSCTL_ONE,
182 		.extra2		= &rt6_multipath_hash_fields_all_mask,
183 	},
184 	{
185 		.procname	= "seg6_flowlabel",
186 		.data		= &init_net.ipv6.sysctl.seg6_flowlabel,
187 		.maxlen		= sizeof(int),
188 		.mode		= 0644,
189 		.proc_handler	= proc_dointvec
190 	},
191 	{
192 		.procname	= "fib_notify_on_flag_change",
193 		.data		= &init_net.ipv6.sysctl.fib_notify_on_flag_change,
194 		.maxlen		= sizeof(u8),
195 		.mode		= 0644,
196 		.proc_handler	= proc_dou8vec_minmax,
197 		.extra1         = SYSCTL_ZERO,
198 		.extra2         = SYSCTL_TWO,
199 	},
200 	{
201 		.procname	= "ioam6_id",
202 		.data		= &init_net.ipv6.sysctl.ioam6_id,
203 		.maxlen		= sizeof(u32),
204 		.mode		= 0644,
205 		.proc_handler	= proc_douintvec_minmax,
206 		.extra2		= &ioam6_id_max,
207 	},
208 	{
209 		.procname	= "ioam6_id_wide",
210 		.data		= &init_net.ipv6.sysctl.ioam6_id_wide,
211 		.maxlen		= sizeof(u64),
212 		.mode		= 0644,
213 		.proc_handler	= proc_doulongvec_minmax,
214 		.extra2		= &ioam6_id_wide_max,
215 	},
216 	{ }
217 };
218 
219 static struct ctl_table ipv6_rotable[] = {
220 	{
221 		.procname	= "mld_max_msf",
222 		.data		= &sysctl_mld_max_msf,
223 		.maxlen		= sizeof(int),
224 		.mode		= 0644,
225 		.proc_handler	= proc_dointvec
226 	},
227 	{
228 		.procname	= "mld_qrv",
229 		.data		= &sysctl_mld_qrv,
230 		.maxlen		= sizeof(int),
231 		.mode		= 0644,
232 		.proc_handler	= proc_dointvec_minmax,
233 		.extra1		= SYSCTL_ONE
234 	},
235 #ifdef CONFIG_NETLABEL
236 	{
237 		.procname	= "calipso_cache_enable",
238 		.data		= &calipso_cache_enabled,
239 		.maxlen		= sizeof(int),
240 		.mode		= 0644,
241 		.proc_handler	= proc_dointvec,
242 	},
243 	{
244 		.procname	= "calipso_cache_bucket_size",
245 		.data		= &calipso_cache_bucketsize,
246 		.maxlen		= sizeof(int),
247 		.mode		= 0644,
248 		.proc_handler	= proc_dointvec,
249 	},
250 #endif /* CONFIG_NETLABEL */
251 	{ }
252 };
253 
254 static int __net_init ipv6_sysctl_net_init(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 	int err, i;
260 
261 	err = -ENOMEM;
262 	ipv6_table = kmemdup(ipv6_table_template, sizeof(ipv6_table_template),
263 			     GFP_KERNEL);
264 	if (!ipv6_table)
265 		goto out;
266 	/* Update the variables to point into the current struct net */
267 	for (i = 0; i < ARRAY_SIZE(ipv6_table_template) - 1; i++)
268 		ipv6_table[i].data += (void *)net - (void *)&init_net;
269 
270 	ipv6_route_table = ipv6_route_sysctl_init(net);
271 	if (!ipv6_route_table)
272 		goto out_ipv6_table;
273 
274 	ipv6_icmp_table = ipv6_icmp_sysctl_init(net);
275 	if (!ipv6_icmp_table)
276 		goto out_ipv6_route_table;
277 
278 	net->ipv6.sysctl.hdr = register_net_sysctl(net, "net/ipv6", ipv6_table);
279 	if (!net->ipv6.sysctl.hdr)
280 		goto out_ipv6_icmp_table;
281 
282 	net->ipv6.sysctl.route_hdr =
283 		register_net_sysctl(net, "net/ipv6/route", ipv6_route_table);
284 	if (!net->ipv6.sysctl.route_hdr)
285 		goto out_unregister_ipv6_table;
286 
287 	net->ipv6.sysctl.icmp_hdr =
288 		register_net_sysctl(net, "net/ipv6/icmp", ipv6_icmp_table);
289 	if (!net->ipv6.sysctl.icmp_hdr)
290 		goto out_unregister_route_table;
291 
292 	err = 0;
293 out:
294 	return err;
295 out_unregister_route_table:
296 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
297 out_unregister_ipv6_table:
298 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
299 out_ipv6_icmp_table:
300 	kfree(ipv6_icmp_table);
301 out_ipv6_route_table:
302 	kfree(ipv6_route_table);
303 out_ipv6_table:
304 	kfree(ipv6_table);
305 	goto out;
306 }
307 
308 static void __net_exit ipv6_sysctl_net_exit(struct net *net)
309 {
310 	struct ctl_table *ipv6_table;
311 	struct ctl_table *ipv6_route_table;
312 	struct ctl_table *ipv6_icmp_table;
313 
314 	ipv6_table = net->ipv6.sysctl.hdr->ctl_table_arg;
315 	ipv6_route_table = net->ipv6.sysctl.route_hdr->ctl_table_arg;
316 	ipv6_icmp_table = net->ipv6.sysctl.icmp_hdr->ctl_table_arg;
317 
318 	unregister_net_sysctl_table(net->ipv6.sysctl.icmp_hdr);
319 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
320 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
321 
322 	kfree(ipv6_table);
323 	kfree(ipv6_route_table);
324 	kfree(ipv6_icmp_table);
325 }
326 
327 static struct pernet_operations ipv6_sysctl_net_ops = {
328 	.init = ipv6_sysctl_net_init,
329 	.exit = ipv6_sysctl_net_exit,
330 };
331 
332 static struct ctl_table_header *ip6_header;
333 
334 int ipv6_sysctl_register(void)
335 {
336 	int err = -ENOMEM;
337 
338 	ip6_header = register_net_sysctl(&init_net, "net/ipv6", ipv6_rotable);
339 	if (!ip6_header)
340 		goto out;
341 
342 	err = register_pernet_subsys(&ipv6_sysctl_net_ops);
343 	if (err)
344 		goto err_pernet;
345 out:
346 	return err;
347 
348 err_pernet:
349 	unregister_net_sysctl_table(ip6_header);
350 	goto out;
351 }
352 
353 void ipv6_sysctl_unregister(void)
354 {
355 	unregister_net_sysctl_table(ip6_header);
356 	unregister_pernet_subsys(&ipv6_sysctl_net_ops);
357 }
358