sysctl_net_ipv4.c revision 4b9d9be839fdb7dcd7ce7619a623fd9015a50cda 
1/*
2 * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
3 *
4 * Begun April 1, 1996, Mike Shaver.
5 * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
6 */
7
8#include <linux/mm.h>
9#include <linux/module.h>
10#include <linux/sysctl.h>
11#include <linux/igmp.h>
12#include <linux/inetdevice.h>
13#include <linux/seqlock.h>
14#include <linux/init.h>
15#include <linux/slab.h>
16#include <linux/nsproxy.h>
17#include <net/snmp.h>
18#include <net/icmp.h>
19#include <net/ip.h>
20#include <net/route.h>
21#include <net/tcp.h>
22#include <net/udp.h>
23#include <net/cipso_ipv4.h>
24#include <net/inet_frag.h>
25#include <net/ping.h>
26
27static int zero;
28static int tcp_retr1_max = 255;
29static int ip_local_port_range_min[] = { 1, 1 };
30static int ip_local_port_range_max[] = { 65535, 65535 };
31static int tcp_adv_win_scale_min = -31;
32static int tcp_adv_win_scale_max = 31;
33static int ip_ttl_min = 1;
34static int ip_ttl_max = 255;
35static int ip_ping_group_range_min[] = { 0, 0 };
36static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
37
38/* Update system visible IP port range */
39static void set_local_port_range(int range[2])
40{
41	write_seqlock(&sysctl_local_ports.lock);
42	sysctl_local_ports.range[0] = range[0];
43	sysctl_local_ports.range[1] = range[1];
44	write_sequnlock(&sysctl_local_ports.lock);
45}
46
47/* Validate changes from /proc interface. */
48static int ipv4_local_port_range(ctl_table *table, int write,
49				 void __user *buffer,
50				 size_t *lenp, loff_t *ppos)
51{
52	int ret;
53	int range[2];
54	ctl_table tmp = {
55		.data = &range,
56		.maxlen = sizeof(range),
57		.mode = table->mode,
58		.extra1 = &ip_local_port_range_min,
59		.extra2 = &ip_local_port_range_max,
60	};
61
62	inet_get_local_port_range(range, range + 1);
63	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
64
65	if (write && ret == 0) {
66		if (range[1] < range[0])
67			ret = -EINVAL;
68		else
69			set_local_port_range(range);
70	}
71
72	return ret;
73}
74
75
76void inet_get_ping_group_range_table(struct ctl_table *table, gid_t *low, gid_t *high)
77{
78	gid_t *data = table->data;
79	unsigned seq;
80	do {
81		seq = read_seqbegin(&sysctl_local_ports.lock);
82
83		*low = data[0];
84		*high = data[1];
85	} while (read_seqretry(&sysctl_local_ports.lock, seq));
86}
87
88/* Update system visible IP port range */
89static void set_ping_group_range(struct ctl_table *table, int range[2])
90{
91	gid_t *data = table->data;
92	write_seqlock(&sysctl_local_ports.lock);
93	data[0] = range[0];
94	data[1] = range[1];
95	write_sequnlock(&sysctl_local_ports.lock);
96}
97
98/* Validate changes from /proc interface. */
99static int ipv4_ping_group_range(ctl_table *table, int write,
100				 void __user *buffer,
101				 size_t *lenp, loff_t *ppos)
102{
103	int ret;
104	gid_t range[2];
105	ctl_table tmp = {
106		.data = &range,
107		.maxlen = sizeof(range),
108		.mode = table->mode,
109		.extra1 = &ip_ping_group_range_min,
110		.extra2 = &ip_ping_group_range_max,
111	};
112
113	inet_get_ping_group_range_table(table, range, range + 1);
114	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
115
116	if (write && ret == 0)
117		set_ping_group_range(table, range);
118
119	return ret;
120}
121
122static int proc_tcp_congestion_control(ctl_table *ctl, int write,
123				       void __user *buffer, size_t *lenp, loff_t *ppos)
124{
125	char val[TCP_CA_NAME_MAX];
126	ctl_table tbl = {
127		.data = val,
128		.maxlen = TCP_CA_NAME_MAX,
129	};
130	int ret;
131
132	tcp_get_default_congestion_control(val);
133
134	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
135	if (write && ret == 0)
136		ret = tcp_set_default_congestion_control(val);
137	return ret;
138}
139
140static int proc_tcp_available_congestion_control(ctl_table *ctl,
141						 int write,
142						 void __user *buffer, size_t *lenp,
143						 loff_t *ppos)
144{
145	ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
146	int ret;
147
148	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
149	if (!tbl.data)
150		return -ENOMEM;
151	tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
152	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
153	kfree(tbl.data);
154	return ret;
155}
156
157static int proc_allowed_congestion_control(ctl_table *ctl,
158					   int write,
159					   void __user *buffer, size_t *lenp,
160					   loff_t *ppos)
161{
162	ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
163	int ret;
164
165	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
166	if (!tbl.data)
167		return -ENOMEM;
168
169	tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
170	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
171	if (write && ret == 0)
172		ret = tcp_set_allowed_congestion_control(tbl.data);
173	kfree(tbl.data);
174	return ret;
175}
176
177static struct ctl_table ipv4_table[] = {
178	{
179		.procname	= "tcp_timestamps",
180		.data		= &sysctl_tcp_timestamps,
181		.maxlen		= sizeof(int),
182		.mode		= 0644,
183		.proc_handler	= proc_dointvec
184	},
185	{
186		.procname	= "tcp_window_scaling",
187		.data		= &sysctl_tcp_window_scaling,
188		.maxlen		= sizeof(int),
189		.mode		= 0644,
190		.proc_handler	= proc_dointvec
191	},
192	{
193		.procname	= "tcp_sack",
194		.data		= &sysctl_tcp_sack,
195		.maxlen		= sizeof(int),
196		.mode		= 0644,
197		.proc_handler	= proc_dointvec
198	},
199	{
200		.procname	= "tcp_retrans_collapse",
201		.data		= &sysctl_tcp_retrans_collapse,
202		.maxlen		= sizeof(int),
203		.mode		= 0644,
204		.proc_handler	= proc_dointvec
205	},
206	{
207		.procname	= "ip_default_ttl",
208		.data		= &sysctl_ip_default_ttl,
209		.maxlen		= sizeof(int),
210		.mode		= 0644,
211		.proc_handler	= proc_dointvec_minmax,
212		.extra1		= &ip_ttl_min,
213		.extra2		= &ip_ttl_max,
214	},
215	{
216		.procname	= "ip_no_pmtu_disc",
217		.data		= &ipv4_config.no_pmtu_disc,
218		.maxlen		= sizeof(int),
219		.mode		= 0644,
220		.proc_handler	= proc_dointvec
221	},
222	{
223		.procname	= "ip_nonlocal_bind",
224		.data		= &sysctl_ip_nonlocal_bind,
225		.maxlen		= sizeof(int),
226		.mode		= 0644,
227		.proc_handler	= proc_dointvec
228	},
229	{
230		.procname	= "tcp_syn_retries",
231		.data		= &sysctl_tcp_syn_retries,
232		.maxlen		= sizeof(int),
233		.mode		= 0644,
234		.proc_handler	= proc_dointvec
235	},
236	{
237		.procname	= "tcp_synack_retries",
238		.data		= &sysctl_tcp_synack_retries,
239		.maxlen		= sizeof(int),
240		.mode		= 0644,
241		.proc_handler	= proc_dointvec
242	},
243	{
244		.procname	= "tcp_max_orphans",
245		.data		= &sysctl_tcp_max_orphans,
246		.maxlen		= sizeof(int),
247		.mode		= 0644,
248		.proc_handler	= proc_dointvec
249	},
250	{
251		.procname	= "tcp_max_tw_buckets",
252		.data		= &tcp_death_row.sysctl_max_tw_buckets,
253		.maxlen		= sizeof(int),
254		.mode		= 0644,
255		.proc_handler	= proc_dointvec
256	},
257	{
258		.procname	= "ip_dynaddr",
259		.data		= &sysctl_ip_dynaddr,
260		.maxlen		= sizeof(int),
261		.mode		= 0644,
262		.proc_handler	= proc_dointvec
263	},
264	{
265		.procname	= "tcp_keepalive_time",
266		.data		= &sysctl_tcp_keepalive_time,
267		.maxlen		= sizeof(int),
268		.mode		= 0644,
269		.proc_handler	= proc_dointvec_jiffies,
270	},
271	{
272		.procname	= "tcp_keepalive_probes",
273		.data		= &sysctl_tcp_keepalive_probes,
274		.maxlen		= sizeof(int),
275		.mode		= 0644,
276		.proc_handler	= proc_dointvec
277	},
278	{
279		.procname	= "tcp_keepalive_intvl",
280		.data		= &sysctl_tcp_keepalive_intvl,
281		.maxlen		= sizeof(int),
282		.mode		= 0644,
283		.proc_handler	= proc_dointvec_jiffies,
284	},
285	{
286		.procname	= "tcp_retries1",
287		.data		= &sysctl_tcp_retries1,
288		.maxlen		= sizeof(int),
289		.mode		= 0644,
290		.proc_handler	= proc_dointvec_minmax,
291		.extra2		= &tcp_retr1_max
292	},
293	{
294		.procname	= "tcp_retries2",
295		.data		= &sysctl_tcp_retries2,
296		.maxlen		= sizeof(int),
297		.mode		= 0644,
298		.proc_handler	= proc_dointvec
299	},
300	{
301		.procname	= "tcp_fin_timeout",
302		.data		= &sysctl_tcp_fin_timeout,
303		.maxlen		= sizeof(int),
304		.mode		= 0644,
305		.proc_handler	= proc_dointvec_jiffies,
306	},
307#ifdef CONFIG_SYN_COOKIES
308	{
309		.procname	= "tcp_syncookies",
310		.data		= &sysctl_tcp_syncookies,
311		.maxlen		= sizeof(int),
312		.mode		= 0644,
313		.proc_handler	= proc_dointvec
314	},
315#endif
316	{
317		.procname	= "tcp_tw_recycle",
318		.data		= &tcp_death_row.sysctl_tw_recycle,
319		.maxlen		= sizeof(int),
320		.mode		= 0644,
321		.proc_handler	= proc_dointvec
322	},
323	{
324		.procname	= "tcp_abort_on_overflow",
325		.data		= &sysctl_tcp_abort_on_overflow,
326		.maxlen		= sizeof(int),
327		.mode		= 0644,
328		.proc_handler	= proc_dointvec
329	},
330	{
331		.procname	= "tcp_stdurg",
332		.data		= &sysctl_tcp_stdurg,
333		.maxlen		= sizeof(int),
334		.mode		= 0644,
335		.proc_handler	= proc_dointvec
336	},
337	{
338		.procname	= "tcp_rfc1337",
339		.data		= &sysctl_tcp_rfc1337,
340		.maxlen		= sizeof(int),
341		.mode		= 0644,
342		.proc_handler	= proc_dointvec
343	},
344	{
345		.procname	= "tcp_max_syn_backlog",
346		.data		= &sysctl_max_syn_backlog,
347		.maxlen		= sizeof(int),
348		.mode		= 0644,
349		.proc_handler	= proc_dointvec
350	},
351	{
352		.procname	= "ip_local_port_range",
353		.data		= &sysctl_local_ports.range,
354		.maxlen		= sizeof(sysctl_local_ports.range),
355		.mode		= 0644,
356		.proc_handler	= ipv4_local_port_range,
357	},
358	{
359		.procname	= "ip_local_reserved_ports",
360		.data		= NULL, /* initialized in sysctl_ipv4_init */
361		.maxlen		= 65536,
362		.mode		= 0644,
363		.proc_handler	= proc_do_large_bitmap,
364	},
365	{
366		.procname	= "igmp_max_memberships",
367		.data		= &sysctl_igmp_max_memberships,
368		.maxlen		= sizeof(int),
369		.mode		= 0644,
370		.proc_handler	= proc_dointvec
371	},
372	{
373		.procname	= "igmp_max_msf",
374		.data		= &sysctl_igmp_max_msf,
375		.maxlen		= sizeof(int),
376		.mode		= 0644,
377		.proc_handler	= proc_dointvec
378	},
379	{
380		.procname	= "inet_peer_threshold",
381		.data		= &inet_peer_threshold,
382		.maxlen		= sizeof(int),
383		.mode		= 0644,
384		.proc_handler	= proc_dointvec
385	},
386	{
387		.procname	= "inet_peer_minttl",
388		.data		= &inet_peer_minttl,
389		.maxlen		= sizeof(int),
390		.mode		= 0644,
391		.proc_handler	= proc_dointvec_jiffies,
392	},
393	{
394		.procname	= "inet_peer_maxttl",
395		.data		= &inet_peer_maxttl,
396		.maxlen		= sizeof(int),
397		.mode		= 0644,
398		.proc_handler	= proc_dointvec_jiffies,
399	},
400	{
401		.procname	= "tcp_orphan_retries",
402		.data		= &sysctl_tcp_orphan_retries,
403		.maxlen		= sizeof(int),
404		.mode		= 0644,
405		.proc_handler	= proc_dointvec
406	},
407	{
408		.procname	= "tcp_fack",
409		.data		= &sysctl_tcp_fack,
410		.maxlen		= sizeof(int),
411		.mode		= 0644,
412		.proc_handler	= proc_dointvec
413	},
414	{
415		.procname	= "tcp_reordering",
416		.data		= &sysctl_tcp_reordering,
417		.maxlen		= sizeof(int),
418		.mode		= 0644,
419		.proc_handler	= proc_dointvec
420	},
421	{
422		.procname	= "tcp_ecn",
423		.data		= &sysctl_tcp_ecn,
424		.maxlen		= sizeof(int),
425		.mode		= 0644,
426		.proc_handler	= proc_dointvec
427	},
428	{
429		.procname	= "tcp_dsack",
430		.data		= &sysctl_tcp_dsack,
431		.maxlen		= sizeof(int),
432		.mode		= 0644,
433		.proc_handler	= proc_dointvec
434	},
435	{
436		.procname	= "tcp_mem",
437		.data		= &sysctl_tcp_mem,
438		.maxlen		= sizeof(sysctl_tcp_mem),
439		.mode		= 0644,
440		.proc_handler	= proc_doulongvec_minmax
441	},
442	{
443		.procname	= "tcp_wmem",
444		.data		= &sysctl_tcp_wmem,
445		.maxlen		= sizeof(sysctl_tcp_wmem),
446		.mode		= 0644,
447		.proc_handler	= proc_dointvec
448	},
449	{
450		.procname	= "tcp_rmem",
451		.data		= &sysctl_tcp_rmem,
452		.maxlen		= sizeof(sysctl_tcp_rmem),
453		.mode		= 0644,
454		.proc_handler	= proc_dointvec
455	},
456	{
457		.procname	= "tcp_app_win",
458		.data		= &sysctl_tcp_app_win,
459		.maxlen		= sizeof(int),
460		.mode		= 0644,
461		.proc_handler	= proc_dointvec
462	},
463	{
464		.procname	= "tcp_adv_win_scale",
465		.data		= &sysctl_tcp_adv_win_scale,
466		.maxlen		= sizeof(int),
467		.mode		= 0644,
468		.proc_handler	= proc_dointvec_minmax,
469		.extra1		= &tcp_adv_win_scale_min,
470		.extra2		= &tcp_adv_win_scale_max,
471	},
472	{
473		.procname	= "tcp_tw_reuse",
474		.data		= &sysctl_tcp_tw_reuse,
475		.maxlen		= sizeof(int),
476		.mode		= 0644,
477		.proc_handler	= proc_dointvec
478	},
479	{
480		.procname	= "tcp_frto",
481		.data		= &sysctl_tcp_frto,
482		.maxlen		= sizeof(int),
483		.mode		= 0644,
484		.proc_handler	= proc_dointvec
485	},
486	{
487		.procname	= "tcp_frto_response",
488		.data		= &sysctl_tcp_frto_response,
489		.maxlen		= sizeof(int),
490		.mode		= 0644,
491		.proc_handler	= proc_dointvec
492	},
493	{
494		.procname	= "tcp_low_latency",
495		.data		= &sysctl_tcp_low_latency,
496		.maxlen		= sizeof(int),
497		.mode		= 0644,
498		.proc_handler	= proc_dointvec
499	},
500	{
501		.procname	= "tcp_no_metrics_save",
502		.data		= &sysctl_tcp_nometrics_save,
503		.maxlen		= sizeof(int),
504		.mode		= 0644,
505		.proc_handler	= proc_dointvec,
506	},
507	{
508		.procname	= "tcp_moderate_rcvbuf",
509		.data		= &sysctl_tcp_moderate_rcvbuf,
510		.maxlen		= sizeof(int),
511		.mode		= 0644,
512		.proc_handler	= proc_dointvec,
513	},
514	{
515		.procname	= "tcp_tso_win_divisor",
516		.data		= &sysctl_tcp_tso_win_divisor,
517		.maxlen		= sizeof(int),
518		.mode		= 0644,
519		.proc_handler	= proc_dointvec,
520	},
521	{
522		.procname	= "tcp_congestion_control",
523		.mode		= 0644,
524		.maxlen		= TCP_CA_NAME_MAX,
525		.proc_handler	= proc_tcp_congestion_control,
526	},
527	{
528		.procname	= "tcp_abc",
529		.data		= &sysctl_tcp_abc,
530		.maxlen		= sizeof(int),
531		.mode		= 0644,
532		.proc_handler	= proc_dointvec,
533	},
534	{
535		.procname	= "tcp_mtu_probing",
536		.data		= &sysctl_tcp_mtu_probing,
537		.maxlen		= sizeof(int),
538		.mode		= 0644,
539		.proc_handler	= proc_dointvec,
540	},
541	{
542		.procname	= "tcp_base_mss",
543		.data		= &sysctl_tcp_base_mss,
544		.maxlen		= sizeof(int),
545		.mode		= 0644,
546		.proc_handler	= proc_dointvec,
547	},
548	{
549		.procname	= "tcp_workaround_signed_windows",
550		.data		= &sysctl_tcp_workaround_signed_windows,
551		.maxlen		= sizeof(int),
552		.mode		= 0644,
553		.proc_handler	= proc_dointvec
554	},
555#ifdef CONFIG_NET_DMA
556	{
557		.procname	= "tcp_dma_copybreak",
558		.data		= &sysctl_tcp_dma_copybreak,
559		.maxlen		= sizeof(int),
560		.mode		= 0644,
561		.proc_handler	= proc_dointvec
562	},
563#endif
564	{
565		.procname	= "tcp_slow_start_after_idle",
566		.data		= &sysctl_tcp_slow_start_after_idle,
567		.maxlen		= sizeof(int),
568		.mode		= 0644,
569		.proc_handler	= proc_dointvec
570	},
571#ifdef CONFIG_NETLABEL
572	{
573		.procname	= "cipso_cache_enable",
574		.data		= &cipso_v4_cache_enabled,
575		.maxlen		= sizeof(int),
576		.mode		= 0644,
577		.proc_handler	= proc_dointvec,
578	},
579	{
580		.procname	= "cipso_cache_bucket_size",
581		.data		= &cipso_v4_cache_bucketsize,
582		.maxlen		= sizeof(int),
583		.mode		= 0644,
584		.proc_handler	= proc_dointvec,
585	},
586	{
587		.procname	= "cipso_rbm_optfmt",
588		.data		= &cipso_v4_rbm_optfmt,
589		.maxlen		= sizeof(int),
590		.mode		= 0644,
591		.proc_handler	= proc_dointvec,
592	},
593	{
594		.procname	= "cipso_rbm_strictvalid",
595		.data		= &cipso_v4_rbm_strictvalid,
596		.maxlen		= sizeof(int),
597		.mode		= 0644,
598		.proc_handler	= proc_dointvec,
599	},
600#endif /* CONFIG_NETLABEL */
601	{
602		.procname	= "tcp_available_congestion_control",
603		.maxlen		= TCP_CA_BUF_MAX,
604		.mode		= 0444,
605		.proc_handler   = proc_tcp_available_congestion_control,
606	},
607	{
608		.procname	= "tcp_allowed_congestion_control",
609		.maxlen		= TCP_CA_BUF_MAX,
610		.mode		= 0644,
611		.proc_handler   = proc_allowed_congestion_control,
612	},
613	{
614		.procname	= "tcp_max_ssthresh",
615		.data		= &sysctl_tcp_max_ssthresh,
616		.maxlen		= sizeof(int),
617		.mode		= 0644,
618		.proc_handler	= proc_dointvec,
619	},
620	{
621		.procname	= "tcp_cookie_size",
622		.data		= &sysctl_tcp_cookie_size,
623		.maxlen		= sizeof(int),
624		.mode		= 0644,
625		.proc_handler	= proc_dointvec
626	},
627	{
628		.procname       = "tcp_thin_linear_timeouts",
629		.data           = &sysctl_tcp_thin_linear_timeouts,
630		.maxlen         = sizeof(int),
631		.mode           = 0644,
632		.proc_handler   = proc_dointvec
633	},
634        {
635		.procname       = "tcp_thin_dupack",
636		.data           = &sysctl_tcp_thin_dupack,
637		.maxlen         = sizeof(int),
638		.mode           = 0644,
639		.proc_handler   = proc_dointvec
640	},
641	{
642		.procname	= "udp_mem",
643		.data		= &sysctl_udp_mem,
644		.maxlen		= sizeof(sysctl_udp_mem),
645		.mode		= 0644,
646		.proc_handler	= proc_doulongvec_minmax,
647	},
648	{
649		.procname	= "udp_rmem_min",
650		.data		= &sysctl_udp_rmem_min,
651		.maxlen		= sizeof(sysctl_udp_rmem_min),
652		.mode		= 0644,
653		.proc_handler	= proc_dointvec_minmax,
654		.extra1		= &zero
655	},
656	{
657		.procname	= "udp_wmem_min",
658		.data		= &sysctl_udp_wmem_min,
659		.maxlen		= sizeof(sysctl_udp_wmem_min),
660		.mode		= 0644,
661		.proc_handler	= proc_dointvec_minmax,
662		.extra1		= &zero
663	},
664	{ }
665};
666
667static struct ctl_table ipv4_net_table[] = {
668	{
669		.procname	= "icmp_echo_ignore_all",
670		.data		= &init_net.ipv4.sysctl_icmp_echo_ignore_all,
671		.maxlen		= sizeof(int),
672		.mode		= 0644,
673		.proc_handler	= proc_dointvec
674	},
675	{
676		.procname	= "icmp_echo_ignore_broadcasts",
677		.data		= &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
678		.maxlen		= sizeof(int),
679		.mode		= 0644,
680		.proc_handler	= proc_dointvec
681	},
682	{
683		.procname	= "icmp_ignore_bogus_error_responses",
684		.data		= &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
685		.maxlen		= sizeof(int),
686		.mode		= 0644,
687		.proc_handler	= proc_dointvec
688	},
689	{
690		.procname	= "icmp_errors_use_inbound_ifaddr",
691		.data		= &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
692		.maxlen		= sizeof(int),
693		.mode		= 0644,
694		.proc_handler	= proc_dointvec
695	},
696	{
697		.procname	= "icmp_ratelimit",
698		.data		= &init_net.ipv4.sysctl_icmp_ratelimit,
699		.maxlen		= sizeof(int),
700		.mode		= 0644,
701		.proc_handler	= proc_dointvec_ms_jiffies,
702	},
703	{
704		.procname	= "icmp_ratemask",
705		.data		= &init_net.ipv4.sysctl_icmp_ratemask,
706		.maxlen		= sizeof(int),
707		.mode		= 0644,
708		.proc_handler	= proc_dointvec
709	},
710	{
711		.procname	= "rt_cache_rebuild_count",
712		.data		= &init_net.ipv4.sysctl_rt_cache_rebuild_count,
713		.maxlen		= sizeof(int),
714		.mode		= 0644,
715		.proc_handler	= proc_dointvec
716	},
717	{
718		.procname	= "ping_group_range",
719		.data		= &init_net.ipv4.sysctl_ping_group_range,
720		.maxlen		= sizeof(init_net.ipv4.sysctl_ping_group_range),
721		.mode		= 0644,
722		.proc_handler	= ipv4_ping_group_range,
723	},
724	{ }
725};
726
727struct ctl_path net_ipv4_ctl_path[] = {
728	{ .procname = "net", },
729	{ .procname = "ipv4", },
730	{ },
731};
732EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
733
734static __net_init int ipv4_sysctl_init_net(struct net *net)
735{
736	struct ctl_table *table;
737
738	table = ipv4_net_table;
739	if (!net_eq(net, &init_net)) {
740		table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
741		if (table == NULL)
742			goto err_alloc;
743
744		table[0].data =
745			&net->ipv4.sysctl_icmp_echo_ignore_all;
746		table[1].data =
747			&net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
748		table[2].data =
749			&net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
750		table[3].data =
751			&net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
752		table[4].data =
753			&net->ipv4.sysctl_icmp_ratelimit;
754		table[5].data =
755			&net->ipv4.sysctl_icmp_ratemask;
756		table[6].data =
757			&net->ipv4.sysctl_rt_cache_rebuild_count;
758		table[7].data =
759			&net->ipv4.sysctl_ping_group_range;
760
761	}
762
763	/*
764	 * Sane defaults - nobody may create ping sockets.
765	 * Boot scripts should set this to distro-specific group.
766	 */
767	net->ipv4.sysctl_ping_group_range[0] = 1;
768	net->ipv4.sysctl_ping_group_range[1] = 0;
769
770	net->ipv4.sysctl_rt_cache_rebuild_count = 4;
771
772	net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
773			net_ipv4_ctl_path, table);
774	if (net->ipv4.ipv4_hdr == NULL)
775		goto err_reg;
776
777	return 0;
778
779err_reg:
780	if (!net_eq(net, &init_net))
781		kfree(table);
782err_alloc:
783	return -ENOMEM;
784}
785
786static __net_exit void ipv4_sysctl_exit_net(struct net *net)
787{
788	struct ctl_table *table;
789
790	table = net->ipv4.ipv4_hdr->ctl_table_arg;
791	unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
792	kfree(table);
793}
794
795static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
796	.init = ipv4_sysctl_init_net,
797	.exit = ipv4_sysctl_exit_net,
798};
799
800static __init int sysctl_ipv4_init(void)
801{
802	struct ctl_table_header *hdr;
803	struct ctl_table *i;
804
805	for (i = ipv4_table; i->procname; i++) {
806		if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
807			i->data = sysctl_local_reserved_ports;
808			break;
809		}
810	}
811	if (!i->procname)
812		return -EINVAL;
813
814	hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
815	if (hdr == NULL)
816		return -ENOMEM;
817
818	if (register_pernet_subsys(&ipv4_sysctl_ops)) {
819		unregister_sysctl_table(hdr);
820		return -ENOMEM;
821	}
822
823	return 0;
824}
825
826__initcall(sysctl_ipv4_init);
827