xref: /linux/net/ipv6/sysctl_net_ipv6.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
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 
proc_rt6_multipath_hash_policy(const struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)33 static int proc_rt6_multipath_hash_policy(const 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
proc_rt6_multipath_hash_fields(const struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)49 proc_rt6_multipath_hash_fields(const 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 static struct ctl_table ipv6_rotable[] = {
219 	{
220 		.procname	= "mld_max_msf",
221 		.data		= &sysctl_mld_max_msf,
222 		.maxlen		= sizeof(int),
223 		.mode		= 0644,
224 		.proc_handler	= proc_dointvec
225 	},
226 	{
227 		.procname	= "mld_qrv",
228 		.data		= &sysctl_mld_qrv,
229 		.maxlen		= sizeof(int),
230 		.mode		= 0644,
231 		.proc_handler	= proc_dointvec_minmax,
232 		.extra1		= SYSCTL_ONE
233 	},
234 #ifdef CONFIG_NETLABEL
235 	{
236 		.procname	= "calipso_cache_enable",
237 		.data		= &calipso_cache_enabled,
238 		.maxlen		= sizeof(int),
239 		.mode		= 0644,
240 		.proc_handler	= proc_dointvec,
241 	},
242 	{
243 		.procname	= "calipso_cache_bucket_size",
244 		.data		= &calipso_cache_bucketsize,
245 		.maxlen		= sizeof(int),
246 		.mode		= 0644,
247 		.proc_handler	= proc_dointvec,
248 	},
249 #endif /* CONFIG_NETLABEL */
250 };
251 
ipv6_sysctl_net_init(struct net * net)252 static int __net_init ipv6_sysctl_net_init(struct net *net)
253 {
254 	size_t table_size = ARRAY_SIZE(ipv6_table_template);
255 	struct ctl_table *ipv6_table;
256 	struct ctl_table *ipv6_route_table;
257 	struct ctl_table *ipv6_icmp_table;
258 	int err, i;
259 
260 	err = -ENOMEM;
261 	ipv6_table = kmemdup(ipv6_table_template, sizeof(ipv6_table_template),
262 			     GFP_KERNEL);
263 	if (!ipv6_table)
264 		goto out;
265 	/* Update the variables to point into the current struct net */
266 	for (i = 0; i < table_size; i++)
267 		ipv6_table[i].data += (void *)net - (void *)&init_net;
268 
269 	ipv6_route_table = ipv6_route_sysctl_init(net);
270 	if (!ipv6_route_table)
271 		goto out_ipv6_table;
272 
273 	ipv6_icmp_table = ipv6_icmp_sysctl_init(net);
274 	if (!ipv6_icmp_table)
275 		goto out_ipv6_route_table;
276 
277 	net->ipv6.sysctl.hdr = register_net_sysctl_sz(net, "net/ipv6",
278 						      ipv6_table, table_size);
279 	if (!net->ipv6.sysctl.hdr)
280 		goto out_ipv6_icmp_table;
281 
282 	net->ipv6.sysctl.route_hdr = register_net_sysctl_sz(net,
283 							    "net/ipv6/route",
284 							    ipv6_route_table,
285 							    ipv6_route_sysctl_table_size(net));
286 	if (!net->ipv6.sysctl.route_hdr)
287 		goto out_unregister_ipv6_table;
288 
289 	net->ipv6.sysctl.icmp_hdr = register_net_sysctl_sz(net,
290 							   "net/ipv6/icmp",
291 							   ipv6_icmp_table,
292 							   ipv6_icmp_sysctl_table_size());
293 	if (!net->ipv6.sysctl.icmp_hdr)
294 		goto out_unregister_route_table;
295 
296 	err = 0;
297 out:
298 	return err;
299 out_unregister_route_table:
300 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
301 out_unregister_ipv6_table:
302 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
303 out_ipv6_icmp_table:
304 	kfree(ipv6_icmp_table);
305 out_ipv6_route_table:
306 	kfree(ipv6_route_table);
307 out_ipv6_table:
308 	kfree(ipv6_table);
309 	goto out;
310 }
311 
ipv6_sysctl_net_exit(struct net * net)312 static void __net_exit ipv6_sysctl_net_exit(struct net *net)
313 {
314 	const struct ctl_table *ipv6_table;
315 	const struct ctl_table *ipv6_route_table;
316 	const struct ctl_table *ipv6_icmp_table;
317 
318 	ipv6_table = net->ipv6.sysctl.hdr->ctl_table_arg;
319 	ipv6_route_table = net->ipv6.sysctl.route_hdr->ctl_table_arg;
320 	ipv6_icmp_table = net->ipv6.sysctl.icmp_hdr->ctl_table_arg;
321 
322 	unregister_net_sysctl_table(net->ipv6.sysctl.icmp_hdr);
323 	unregister_net_sysctl_table(net->ipv6.sysctl.route_hdr);
324 	unregister_net_sysctl_table(net->ipv6.sysctl.hdr);
325 
326 	kfree(ipv6_table);
327 	kfree(ipv6_route_table);
328 	kfree(ipv6_icmp_table);
329 }
330 
331 static struct pernet_operations ipv6_sysctl_net_ops = {
332 	.init = ipv6_sysctl_net_init,
333 	.exit = ipv6_sysctl_net_exit,
334 };
335 
336 static struct ctl_table_header *ip6_header;
337 
ipv6_sysctl_register(void)338 int ipv6_sysctl_register(void)
339 {
340 	int err = -ENOMEM;
341 
342 	ip6_header = register_net_sysctl(&init_net, "net/ipv6", ipv6_rotable);
343 	if (!ip6_header)
344 		goto out;
345 
346 	err = register_pernet_subsys(&ipv6_sysctl_net_ops);
347 	if (err)
348 		goto err_pernet;
349 out:
350 	return err;
351 
352 err_pernet:
353 	unregister_net_sysctl_table(ip6_header);
354 	goto out;
355 }
356 
ipv6_sysctl_unregister(void)357 void ipv6_sysctl_unregister(void)
358 {
359 	unregister_net_sysctl_table(ip6_header);
360 	unregister_pernet_subsys(&ipv6_sysctl_net_ops);
361 }
362