2 * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
4 * Begun April 1, 1996, Mike Shaver.
5 * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
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>
20 #include <net/route.h>
23 #include <net/cipso_ipv4.h>
24 #include <net/inet_frag.h>
28 static int tcp_retr1_max = 255;
29 static int ip_local_port_range_min[] = { 1, 1 };
30 static int ip_local_port_range_max[] = { 65535, 65535 };
31 static int tcp_adv_win_scale_min = -31;
32 static int tcp_adv_win_scale_max = 31;
33 static int ip_ttl_min = 1;
34 static int ip_ttl_max = 255;
35 static int tcp_syn_retries_min = 1;
36 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
37 static int ip_ping_group_range_min[] = { 0, 0 };
38 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
40 /* Update system visible IP port range */
41 static void set_local_port_range(int range[2])
43 write_seqlock(&sysctl_local_ports.lock);
44 sysctl_local_ports.range[0] = range[0];
45 sysctl_local_ports.range[1] = range[1];
46 write_sequnlock(&sysctl_local_ports.lock);
49 /* Validate changes from /proc interface. */
50 static int ipv4_local_port_range(ctl_table *table, int write,
52 size_t *lenp, loff_t *ppos)
58 .maxlen = sizeof(range),
60 .extra1 = &ip_local_port_range_min,
61 .extra2 = &ip_local_port_range_max,
64 inet_get_local_port_range(range, range + 1);
65 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
67 if (write && ret == 0) {
68 if (range[1] < range[0])
71 set_local_port_range(range);
78 void inet_get_ping_group_range_table(struct ctl_table *table, gid_t *low, gid_t *high)
80 gid_t *data = table->data;
83 seq = read_seqbegin(&sysctl_local_ports.lock);
87 } while (read_seqretry(&sysctl_local_ports.lock, seq));
90 /* Update system visible IP port range */
91 static void set_ping_group_range(struct ctl_table *table, int range[2])
93 gid_t *data = table->data;
94 write_seqlock(&sysctl_local_ports.lock);
97 write_sequnlock(&sysctl_local_ports.lock);
100 /* Validate changes from /proc interface. */
101 static int ipv4_ping_group_range(ctl_table *table, int write,
103 size_t *lenp, loff_t *ppos)
109 .maxlen = sizeof(range),
111 .extra1 = &ip_ping_group_range_min,
112 .extra2 = &ip_ping_group_range_max,
115 inet_get_ping_group_range_table(table, range, range + 1);
116 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
118 if (write && ret == 0)
119 set_ping_group_range(table, range);
124 static int proc_tcp_congestion_control(ctl_table *ctl, int write,
125 void __user *buffer, size_t *lenp, loff_t *ppos)
127 char val[TCP_CA_NAME_MAX];
130 .maxlen = TCP_CA_NAME_MAX,
134 tcp_get_default_congestion_control(val);
136 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
137 if (write && ret == 0)
138 ret = tcp_set_default_congestion_control(val);
142 static int proc_tcp_available_congestion_control(ctl_table *ctl,
144 void __user *buffer, size_t *lenp,
147 ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
150 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
153 tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
154 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
159 static int proc_allowed_congestion_control(ctl_table *ctl,
161 void __user *buffer, size_t *lenp,
164 ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
167 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
171 tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
172 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
173 if (write && ret == 0)
174 ret = tcp_set_allowed_congestion_control(tbl.data);
179 static struct ctl_table ipv4_table[] = {
181 .procname = "tcp_timestamps",
182 .data = &sysctl_tcp_timestamps,
183 .maxlen = sizeof(int),
185 .proc_handler = proc_dointvec
188 .procname = "tcp_window_scaling",
189 .data = &sysctl_tcp_window_scaling,
190 .maxlen = sizeof(int),
192 .proc_handler = proc_dointvec
195 .procname = "tcp_sack",
196 .data = &sysctl_tcp_sack,
197 .maxlen = sizeof(int),
199 .proc_handler = proc_dointvec
202 .procname = "tcp_retrans_collapse",
203 .data = &sysctl_tcp_retrans_collapse,
204 .maxlen = sizeof(int),
206 .proc_handler = proc_dointvec
209 .procname = "ip_default_ttl",
210 .data = &sysctl_ip_default_ttl,
211 .maxlen = sizeof(int),
213 .proc_handler = proc_dointvec_minmax,
214 .extra1 = &ip_ttl_min,
215 .extra2 = &ip_ttl_max,
218 .procname = "ip_no_pmtu_disc",
219 .data = &ipv4_config.no_pmtu_disc,
220 .maxlen = sizeof(int),
222 .proc_handler = proc_dointvec
225 .procname = "ip_nonlocal_bind",
226 .data = &sysctl_ip_nonlocal_bind,
227 .maxlen = sizeof(int),
229 .proc_handler = proc_dointvec
232 .procname = "tcp_syn_retries",
233 .data = &sysctl_tcp_syn_retries,
234 .maxlen = sizeof(int),
236 .proc_handler = proc_dointvec_minmax,
237 .extra1 = &tcp_syn_retries_min,
238 .extra2 = &tcp_syn_retries_max
241 .procname = "tcp_synack_retries",
242 .data = &sysctl_tcp_synack_retries,
243 .maxlen = sizeof(int),
245 .proc_handler = proc_dointvec
248 .procname = "tcp_max_orphans",
249 .data = &sysctl_tcp_max_orphans,
250 .maxlen = sizeof(int),
252 .proc_handler = proc_dointvec
255 .procname = "tcp_max_tw_buckets",
256 .data = &tcp_death_row.sysctl_max_tw_buckets,
257 .maxlen = sizeof(int),
259 .proc_handler = proc_dointvec
262 .procname = "ip_dynaddr",
263 .data = &sysctl_ip_dynaddr,
264 .maxlen = sizeof(int),
266 .proc_handler = proc_dointvec
269 .procname = "tcp_keepalive_time",
270 .data = &sysctl_tcp_keepalive_time,
271 .maxlen = sizeof(int),
273 .proc_handler = proc_dointvec_jiffies,
276 .procname = "tcp_keepalive_probes",
277 .data = &sysctl_tcp_keepalive_probes,
278 .maxlen = sizeof(int),
280 .proc_handler = proc_dointvec
283 .procname = "tcp_keepalive_intvl",
284 .data = &sysctl_tcp_keepalive_intvl,
285 .maxlen = sizeof(int),
287 .proc_handler = proc_dointvec_jiffies,
290 .procname = "tcp_retries1",
291 .data = &sysctl_tcp_retries1,
292 .maxlen = sizeof(int),
294 .proc_handler = proc_dointvec_minmax,
295 .extra2 = &tcp_retr1_max
298 .procname = "tcp_retries2",
299 .data = &sysctl_tcp_retries2,
300 .maxlen = sizeof(int),
302 .proc_handler = proc_dointvec
305 .procname = "tcp_fin_timeout",
306 .data = &sysctl_tcp_fin_timeout,
307 .maxlen = sizeof(int),
309 .proc_handler = proc_dointvec_jiffies,
311 #ifdef CONFIG_SYN_COOKIES
313 .procname = "tcp_syncookies",
314 .data = &sysctl_tcp_syncookies,
315 .maxlen = sizeof(int),
317 .proc_handler = proc_dointvec
321 .procname = "tcp_tw_recycle",
322 .data = &tcp_death_row.sysctl_tw_recycle,
323 .maxlen = sizeof(int),
325 .proc_handler = proc_dointvec
328 .procname = "tcp_abort_on_overflow",
329 .data = &sysctl_tcp_abort_on_overflow,
330 .maxlen = sizeof(int),
332 .proc_handler = proc_dointvec
335 .procname = "tcp_stdurg",
336 .data = &sysctl_tcp_stdurg,
337 .maxlen = sizeof(int),
339 .proc_handler = proc_dointvec
342 .procname = "tcp_rfc1337",
343 .data = &sysctl_tcp_rfc1337,
344 .maxlen = sizeof(int),
346 .proc_handler = proc_dointvec
349 .procname = "tcp_max_syn_backlog",
350 .data = &sysctl_max_syn_backlog,
351 .maxlen = sizeof(int),
353 .proc_handler = proc_dointvec
356 .procname = "ip_local_port_range",
357 .data = &sysctl_local_ports.range,
358 .maxlen = sizeof(sysctl_local_ports.range),
360 .proc_handler = ipv4_local_port_range,
363 .procname = "ip_local_reserved_ports",
364 .data = NULL, /* initialized in sysctl_ipv4_init */
367 .proc_handler = proc_do_large_bitmap,
370 .procname = "igmp_max_memberships",
371 .data = &sysctl_igmp_max_memberships,
372 .maxlen = sizeof(int),
374 .proc_handler = proc_dointvec
377 .procname = "igmp_max_msf",
378 .data = &sysctl_igmp_max_msf,
379 .maxlen = sizeof(int),
381 .proc_handler = proc_dointvec
384 .procname = "inet_peer_threshold",
385 .data = &inet_peer_threshold,
386 .maxlen = sizeof(int),
388 .proc_handler = proc_dointvec
391 .procname = "inet_peer_minttl",
392 .data = &inet_peer_minttl,
393 .maxlen = sizeof(int),
395 .proc_handler = proc_dointvec_jiffies,
398 .procname = "inet_peer_maxttl",
399 .data = &inet_peer_maxttl,
400 .maxlen = sizeof(int),
402 .proc_handler = proc_dointvec_jiffies,
405 .procname = "tcp_orphan_retries",
406 .data = &sysctl_tcp_orphan_retries,
407 .maxlen = sizeof(int),
409 .proc_handler = proc_dointvec
412 .procname = "tcp_fack",
413 .data = &sysctl_tcp_fack,
414 .maxlen = sizeof(int),
416 .proc_handler = proc_dointvec
419 .procname = "tcp_reordering",
420 .data = &sysctl_tcp_reordering,
421 .maxlen = sizeof(int),
423 .proc_handler = proc_dointvec
426 .procname = "tcp_ecn",
427 .data = &sysctl_tcp_ecn,
428 .maxlen = sizeof(int),
430 .proc_handler = proc_dointvec
433 .procname = "tcp_dsack",
434 .data = &sysctl_tcp_dsack,
435 .maxlen = sizeof(int),
437 .proc_handler = proc_dointvec
440 .procname = "tcp_mem",
441 .data = &sysctl_tcp_mem,
442 .maxlen = sizeof(sysctl_tcp_mem),
444 .proc_handler = proc_doulongvec_minmax
447 .procname = "tcp_wmem",
448 .data = &sysctl_tcp_wmem,
449 .maxlen = sizeof(sysctl_tcp_wmem),
451 .proc_handler = proc_dointvec
454 .procname = "tcp_rmem",
455 .data = &sysctl_tcp_rmem,
456 .maxlen = sizeof(sysctl_tcp_rmem),
458 .proc_handler = proc_dointvec
461 .procname = "tcp_app_win",
462 .data = &sysctl_tcp_app_win,
463 .maxlen = sizeof(int),
465 .proc_handler = proc_dointvec
468 .procname = "tcp_adv_win_scale",
469 .data = &sysctl_tcp_adv_win_scale,
470 .maxlen = sizeof(int),
472 .proc_handler = proc_dointvec_minmax,
473 .extra1 = &tcp_adv_win_scale_min,
474 .extra2 = &tcp_adv_win_scale_max,
477 .procname = "tcp_tw_reuse",
478 .data = &sysctl_tcp_tw_reuse,
479 .maxlen = sizeof(int),
481 .proc_handler = proc_dointvec
484 .procname = "tcp_frto",
485 .data = &sysctl_tcp_frto,
486 .maxlen = sizeof(int),
488 .proc_handler = proc_dointvec
491 .procname = "tcp_frto_response",
492 .data = &sysctl_tcp_frto_response,
493 .maxlen = sizeof(int),
495 .proc_handler = proc_dointvec
498 .procname = "tcp_low_latency",
499 .data = &sysctl_tcp_low_latency,
500 .maxlen = sizeof(int),
502 .proc_handler = proc_dointvec
505 .procname = "tcp_no_metrics_save",
506 .data = &sysctl_tcp_nometrics_save,
507 .maxlen = sizeof(int),
509 .proc_handler = proc_dointvec,
512 .procname = "tcp_moderate_rcvbuf",
513 .data = &sysctl_tcp_moderate_rcvbuf,
514 .maxlen = sizeof(int),
516 .proc_handler = proc_dointvec,
519 .procname = "tcp_tso_win_divisor",
520 .data = &sysctl_tcp_tso_win_divisor,
521 .maxlen = sizeof(int),
523 .proc_handler = proc_dointvec,
526 .procname = "tcp_congestion_control",
528 .maxlen = TCP_CA_NAME_MAX,
529 .proc_handler = proc_tcp_congestion_control,
532 .procname = "tcp_abc",
533 .data = &sysctl_tcp_abc,
534 .maxlen = sizeof(int),
536 .proc_handler = proc_dointvec,
539 .procname = "tcp_mtu_probing",
540 .data = &sysctl_tcp_mtu_probing,
541 .maxlen = sizeof(int),
543 .proc_handler = proc_dointvec,
546 .procname = "tcp_base_mss",
547 .data = &sysctl_tcp_base_mss,
548 .maxlen = sizeof(int),
550 .proc_handler = proc_dointvec,
553 .procname = "tcp_workaround_signed_windows",
554 .data = &sysctl_tcp_workaround_signed_windows,
555 .maxlen = sizeof(int),
557 .proc_handler = proc_dointvec
560 .procname = "tcp_challenge_ack_limit",
561 .data = &sysctl_tcp_challenge_ack_limit,
562 .maxlen = sizeof(int),
564 .proc_handler = proc_dointvec
566 #ifdef CONFIG_NET_DMA
568 .procname = "tcp_dma_copybreak",
569 .data = &sysctl_tcp_dma_copybreak,
570 .maxlen = sizeof(int),
572 .proc_handler = proc_dointvec
576 .procname = "tcp_slow_start_after_idle",
577 .data = &sysctl_tcp_slow_start_after_idle,
578 .maxlen = sizeof(int),
580 .proc_handler = proc_dointvec
582 #ifdef CONFIG_NETLABEL
584 .procname = "cipso_cache_enable",
585 .data = &cipso_v4_cache_enabled,
586 .maxlen = sizeof(int),
588 .proc_handler = proc_dointvec,
591 .procname = "cipso_cache_bucket_size",
592 .data = &cipso_v4_cache_bucketsize,
593 .maxlen = sizeof(int),
595 .proc_handler = proc_dointvec,
598 .procname = "cipso_rbm_optfmt",
599 .data = &cipso_v4_rbm_optfmt,
600 .maxlen = sizeof(int),
602 .proc_handler = proc_dointvec,
605 .procname = "cipso_rbm_strictvalid",
606 .data = &cipso_v4_rbm_strictvalid,
607 .maxlen = sizeof(int),
609 .proc_handler = proc_dointvec,
611 #endif /* CONFIG_NETLABEL */
613 .procname = "tcp_available_congestion_control",
614 .maxlen = TCP_CA_BUF_MAX,
616 .proc_handler = proc_tcp_available_congestion_control,
619 .procname = "tcp_allowed_congestion_control",
620 .maxlen = TCP_CA_BUF_MAX,
622 .proc_handler = proc_allowed_congestion_control,
625 .procname = "tcp_max_ssthresh",
626 .data = &sysctl_tcp_max_ssthresh,
627 .maxlen = sizeof(int),
629 .proc_handler = proc_dointvec,
632 .procname = "tcp_cookie_size",
633 .data = &sysctl_tcp_cookie_size,
634 .maxlen = sizeof(int),
636 .proc_handler = proc_dointvec
639 .procname = "tcp_thin_linear_timeouts",
640 .data = &sysctl_tcp_thin_linear_timeouts,
641 .maxlen = sizeof(int),
643 .proc_handler = proc_dointvec
646 .procname = "tcp_thin_dupack",
647 .data = &sysctl_tcp_thin_dupack,
648 .maxlen = sizeof(int),
650 .proc_handler = proc_dointvec
653 .procname = "udp_mem",
654 .data = &sysctl_udp_mem,
655 .maxlen = sizeof(sysctl_udp_mem),
657 .proc_handler = proc_doulongvec_minmax,
660 .procname = "udp_rmem_min",
661 .data = &sysctl_udp_rmem_min,
662 .maxlen = sizeof(sysctl_udp_rmem_min),
664 .proc_handler = proc_dointvec_minmax,
668 .procname = "udp_wmem_min",
669 .data = &sysctl_udp_wmem_min,
670 .maxlen = sizeof(sysctl_udp_wmem_min),
672 .proc_handler = proc_dointvec_minmax,
678 static struct ctl_table ipv4_net_table[] = {
680 .procname = "icmp_echo_ignore_all",
681 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
682 .maxlen = sizeof(int),
684 .proc_handler = proc_dointvec
687 .procname = "icmp_echo_ignore_broadcasts",
688 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
689 .maxlen = sizeof(int),
691 .proc_handler = proc_dointvec
694 .procname = "icmp_ignore_bogus_error_responses",
695 .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
696 .maxlen = sizeof(int),
698 .proc_handler = proc_dointvec
701 .procname = "icmp_errors_use_inbound_ifaddr",
702 .data = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
703 .maxlen = sizeof(int),
705 .proc_handler = proc_dointvec
708 .procname = "icmp_ratelimit",
709 .data = &init_net.ipv4.sysctl_icmp_ratelimit,
710 .maxlen = sizeof(int),
712 .proc_handler = proc_dointvec_ms_jiffies,
715 .procname = "icmp_ratemask",
716 .data = &init_net.ipv4.sysctl_icmp_ratemask,
717 .maxlen = sizeof(int),
719 .proc_handler = proc_dointvec
722 .procname = "rt_cache_rebuild_count",
723 .data = &init_net.ipv4.sysctl_rt_cache_rebuild_count,
724 .maxlen = sizeof(int),
726 .proc_handler = proc_dointvec
729 .procname = "ping_group_range",
730 .data = &init_net.ipv4.sysctl_ping_group_range,
731 .maxlen = sizeof(init_net.ipv4.sysctl_ping_group_range),
733 .proc_handler = ipv4_ping_group_range,
738 struct ctl_path net_ipv4_ctl_path[] = {
739 { .procname = "net", },
740 { .procname = "ipv4", },
743 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
745 static __net_init int ipv4_sysctl_init_net(struct net *net)
747 struct ctl_table *table;
749 table = ipv4_net_table;
750 if (!net_eq(net, &init_net)) {
751 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
756 &net->ipv4.sysctl_icmp_echo_ignore_all;
758 &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
760 &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
762 &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
764 &net->ipv4.sysctl_icmp_ratelimit;
766 &net->ipv4.sysctl_icmp_ratemask;
768 &net->ipv4.sysctl_rt_cache_rebuild_count;
770 &net->ipv4.sysctl_ping_group_range;
775 * Sane defaults - nobody may create ping sockets.
776 * Boot scripts should set this to distro-specific group.
778 net->ipv4.sysctl_ping_group_range[0] = 1;
779 net->ipv4.sysctl_ping_group_range[1] = 0;
781 net->ipv4.sysctl_rt_cache_rebuild_count = 4;
783 net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
784 net_ipv4_ctl_path, table);
785 if (net->ipv4.ipv4_hdr == NULL)
791 if (!net_eq(net, &init_net))
797 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
799 struct ctl_table *table;
801 table = net->ipv4.ipv4_hdr->ctl_table_arg;
802 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
806 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
807 .init = ipv4_sysctl_init_net,
808 .exit = ipv4_sysctl_exit_net,
811 static __init int sysctl_ipv4_init(void)
813 struct ctl_table_header *hdr;
816 for (i = ipv4_table; i->procname; i++) {
817 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
818 i->data = sysctl_local_reserved_ports;
825 hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
829 if (register_pernet_subsys(&ipv4_sysctl_ops)) {
830 unregister_sysctl_table(hdr);
837 __initcall(sysctl_ipv4_init);