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>
17 #include <linux/swap.h>
21 #include <net/route.h>
24 #include <net/cipso_ipv4.h>
25 #include <net/inet_frag.h>
29 static int tcp_retr1_max = 255;
30 static int ip_local_port_range_min[] = { 1, 1 };
31 static int ip_local_port_range_max[] = { 65535, 65535 };
32 static int tcp_adv_win_scale_min = -31;
33 static int tcp_adv_win_scale_max = 31;
34 static int ip_ttl_min = 1;
35 static int ip_ttl_max = 255;
36 static int ip_ping_group_range_min[] = { 0, 0 };
37 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
39 /* Update system visible IP port range */
40 static void set_local_port_range(int range[2])
42 write_seqlock(&sysctl_local_ports.lock);
43 sysctl_local_ports.range[0] = range[0];
44 sysctl_local_ports.range[1] = range[1];
45 write_sequnlock(&sysctl_local_ports.lock);
48 /* Validate changes from /proc interface. */
49 static int ipv4_local_port_range(ctl_table *table, int write,
51 size_t *lenp, loff_t *ppos)
57 .maxlen = sizeof(range),
59 .extra1 = &ip_local_port_range_min,
60 .extra2 = &ip_local_port_range_max,
63 inet_get_local_port_range(range, range + 1);
64 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
66 if (write && ret == 0) {
67 if (range[1] < range[0])
70 set_local_port_range(range);
77 void inet_get_ping_group_range_table(struct ctl_table *table, gid_t *low, gid_t *high)
79 gid_t *data = table->data;
82 seq = read_seqbegin(&sysctl_local_ports.lock);
86 } while (read_seqretry(&sysctl_local_ports.lock, seq));
89 /* Update system visible IP port range */
90 static void set_ping_group_range(struct ctl_table *table, int range[2])
92 gid_t *data = table->data;
93 write_seqlock(&sysctl_local_ports.lock);
96 write_sequnlock(&sysctl_local_ports.lock);
99 /* Validate changes from /proc interface. */
100 static int ipv4_ping_group_range(ctl_table *table, int write,
102 size_t *lenp, loff_t *ppos)
108 .maxlen = sizeof(range),
110 .extra1 = &ip_ping_group_range_min,
111 .extra2 = &ip_ping_group_range_max,
114 inet_get_ping_group_range_table(table, range, range + 1);
115 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
117 if (write && ret == 0)
118 set_ping_group_range(table, range);
123 static int proc_tcp_congestion_control(ctl_table *ctl, int write,
124 void __user *buffer, size_t *lenp, loff_t *ppos)
126 char val[TCP_CA_NAME_MAX];
129 .maxlen = TCP_CA_NAME_MAX,
133 tcp_get_default_congestion_control(val);
135 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
136 if (write && ret == 0)
137 ret = tcp_set_default_congestion_control(val);
141 static int proc_tcp_available_congestion_control(ctl_table *ctl,
143 void __user *buffer, size_t *lenp,
146 ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
149 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
152 tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
153 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
158 static int proc_allowed_congestion_control(ctl_table *ctl,
160 void __user *buffer, size_t *lenp,
163 ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
166 tbl.data = kmalloc(tbl.maxlen, GFP_USER);
170 tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
171 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
172 if (write && ret == 0)
173 ret = tcp_set_allowed_congestion_control(tbl.data);
178 static int ipv4_tcp_mem(ctl_table *ctl, int write,
179 void __user *buffer, size_t *lenp,
183 unsigned long vec[3];
184 struct net *net = current->nsproxy->net_ns;
188 .maxlen = sizeof(vec),
193 ctl->data = &net->ipv4.sysctl_tcp_mem;
194 return proc_doulongvec_minmax(ctl, write, buffer, lenp, ppos);
197 ret = proc_doulongvec_minmax(&tmp, write, buffer, lenp, ppos);
201 net->ipv4.sysctl_tcp_mem[0] = vec[0];
202 net->ipv4.sysctl_tcp_mem[1] = vec[1];
203 net->ipv4.sysctl_tcp_mem[2] = vec[2];
208 static struct ctl_table ipv4_table[] = {
210 .procname = "tcp_timestamps",
211 .data = &sysctl_tcp_timestamps,
212 .maxlen = sizeof(int),
214 .proc_handler = proc_dointvec
217 .procname = "tcp_window_scaling",
218 .data = &sysctl_tcp_window_scaling,
219 .maxlen = sizeof(int),
221 .proc_handler = proc_dointvec
224 .procname = "tcp_sack",
225 .data = &sysctl_tcp_sack,
226 .maxlen = sizeof(int),
228 .proc_handler = proc_dointvec
231 .procname = "tcp_retrans_collapse",
232 .data = &sysctl_tcp_retrans_collapse,
233 .maxlen = sizeof(int),
235 .proc_handler = proc_dointvec
238 .procname = "ip_default_ttl",
239 .data = &sysctl_ip_default_ttl,
240 .maxlen = sizeof(int),
242 .proc_handler = proc_dointvec_minmax,
243 .extra1 = &ip_ttl_min,
244 .extra2 = &ip_ttl_max,
247 .procname = "ip_no_pmtu_disc",
248 .data = &ipv4_config.no_pmtu_disc,
249 .maxlen = sizeof(int),
251 .proc_handler = proc_dointvec
254 .procname = "ip_nonlocal_bind",
255 .data = &sysctl_ip_nonlocal_bind,
256 .maxlen = sizeof(int),
258 .proc_handler = proc_dointvec
261 .procname = "tcp_syn_retries",
262 .data = &sysctl_tcp_syn_retries,
263 .maxlen = sizeof(int),
265 .proc_handler = proc_dointvec
268 .procname = "tcp_synack_retries",
269 .data = &sysctl_tcp_synack_retries,
270 .maxlen = sizeof(int),
272 .proc_handler = proc_dointvec
275 .procname = "tcp_max_orphans",
276 .data = &sysctl_tcp_max_orphans,
277 .maxlen = sizeof(int),
279 .proc_handler = proc_dointvec
282 .procname = "tcp_max_tw_buckets",
283 .data = &tcp_death_row.sysctl_max_tw_buckets,
284 .maxlen = sizeof(int),
286 .proc_handler = proc_dointvec
289 .procname = "ip_dynaddr",
290 .data = &sysctl_ip_dynaddr,
291 .maxlen = sizeof(int),
293 .proc_handler = proc_dointvec
296 .procname = "tcp_keepalive_time",
297 .data = &sysctl_tcp_keepalive_time,
298 .maxlen = sizeof(int),
300 .proc_handler = proc_dointvec_jiffies,
303 .procname = "tcp_keepalive_probes",
304 .data = &sysctl_tcp_keepalive_probes,
305 .maxlen = sizeof(int),
307 .proc_handler = proc_dointvec
310 .procname = "tcp_keepalive_intvl",
311 .data = &sysctl_tcp_keepalive_intvl,
312 .maxlen = sizeof(int),
314 .proc_handler = proc_dointvec_jiffies,
317 .procname = "tcp_retries1",
318 .data = &sysctl_tcp_retries1,
319 .maxlen = sizeof(int),
321 .proc_handler = proc_dointvec_minmax,
322 .extra2 = &tcp_retr1_max
325 .procname = "tcp_retries2",
326 .data = &sysctl_tcp_retries2,
327 .maxlen = sizeof(int),
329 .proc_handler = proc_dointvec
332 .procname = "tcp_fin_timeout",
333 .data = &sysctl_tcp_fin_timeout,
334 .maxlen = sizeof(int),
336 .proc_handler = proc_dointvec_jiffies,
338 #ifdef CONFIG_SYN_COOKIES
340 .procname = "tcp_syncookies",
341 .data = &sysctl_tcp_syncookies,
342 .maxlen = sizeof(int),
344 .proc_handler = proc_dointvec
348 .procname = "tcp_tw_recycle",
349 .data = &tcp_death_row.sysctl_tw_recycle,
350 .maxlen = sizeof(int),
352 .proc_handler = proc_dointvec
355 .procname = "tcp_abort_on_overflow",
356 .data = &sysctl_tcp_abort_on_overflow,
357 .maxlen = sizeof(int),
359 .proc_handler = proc_dointvec
362 .procname = "tcp_stdurg",
363 .data = &sysctl_tcp_stdurg,
364 .maxlen = sizeof(int),
366 .proc_handler = proc_dointvec
369 .procname = "tcp_rfc1337",
370 .data = &sysctl_tcp_rfc1337,
371 .maxlen = sizeof(int),
373 .proc_handler = proc_dointvec
376 .procname = "tcp_max_syn_backlog",
377 .data = &sysctl_max_syn_backlog,
378 .maxlen = sizeof(int),
380 .proc_handler = proc_dointvec
383 .procname = "ip_local_port_range",
384 .data = &sysctl_local_ports.range,
385 .maxlen = sizeof(sysctl_local_ports.range),
387 .proc_handler = ipv4_local_port_range,
390 .procname = "ip_local_reserved_ports",
391 .data = NULL, /* initialized in sysctl_ipv4_init */
394 .proc_handler = proc_do_large_bitmap,
397 .procname = "igmp_max_memberships",
398 .data = &sysctl_igmp_max_memberships,
399 .maxlen = sizeof(int),
401 .proc_handler = proc_dointvec
404 .procname = "igmp_max_msf",
405 .data = &sysctl_igmp_max_msf,
406 .maxlen = sizeof(int),
408 .proc_handler = proc_dointvec
411 .procname = "inet_peer_threshold",
412 .data = &inet_peer_threshold,
413 .maxlen = sizeof(int),
415 .proc_handler = proc_dointvec
418 .procname = "inet_peer_minttl",
419 .data = &inet_peer_minttl,
420 .maxlen = sizeof(int),
422 .proc_handler = proc_dointvec_jiffies,
425 .procname = "inet_peer_maxttl",
426 .data = &inet_peer_maxttl,
427 .maxlen = sizeof(int),
429 .proc_handler = proc_dointvec_jiffies,
432 .procname = "tcp_orphan_retries",
433 .data = &sysctl_tcp_orphan_retries,
434 .maxlen = sizeof(int),
436 .proc_handler = proc_dointvec
439 .procname = "tcp_fack",
440 .data = &sysctl_tcp_fack,
441 .maxlen = sizeof(int),
443 .proc_handler = proc_dointvec
446 .procname = "tcp_reordering",
447 .data = &sysctl_tcp_reordering,
448 .maxlen = sizeof(int),
450 .proc_handler = proc_dointvec
453 .procname = "tcp_ecn",
454 .data = &sysctl_tcp_ecn,
455 .maxlen = sizeof(int),
457 .proc_handler = proc_dointvec
460 .procname = "tcp_dsack",
461 .data = &sysctl_tcp_dsack,
462 .maxlen = sizeof(int),
464 .proc_handler = proc_dointvec
467 .procname = "tcp_wmem",
468 .data = &sysctl_tcp_wmem,
469 .maxlen = sizeof(sysctl_tcp_wmem),
471 .proc_handler = proc_dointvec
474 .procname = "tcp_rmem",
475 .data = &sysctl_tcp_rmem,
476 .maxlen = sizeof(sysctl_tcp_rmem),
478 .proc_handler = proc_dointvec
481 .procname = "tcp_app_win",
482 .data = &sysctl_tcp_app_win,
483 .maxlen = sizeof(int),
485 .proc_handler = proc_dointvec
488 .procname = "tcp_adv_win_scale",
489 .data = &sysctl_tcp_adv_win_scale,
490 .maxlen = sizeof(int),
492 .proc_handler = proc_dointvec_minmax,
493 .extra1 = &tcp_adv_win_scale_min,
494 .extra2 = &tcp_adv_win_scale_max,
497 .procname = "tcp_tw_reuse",
498 .data = &sysctl_tcp_tw_reuse,
499 .maxlen = sizeof(int),
501 .proc_handler = proc_dointvec
504 .procname = "tcp_frto",
505 .data = &sysctl_tcp_frto,
506 .maxlen = sizeof(int),
508 .proc_handler = proc_dointvec
511 .procname = "tcp_frto_response",
512 .data = &sysctl_tcp_frto_response,
513 .maxlen = sizeof(int),
515 .proc_handler = proc_dointvec
518 .procname = "tcp_low_latency",
519 .data = &sysctl_tcp_low_latency,
520 .maxlen = sizeof(int),
522 .proc_handler = proc_dointvec
525 .procname = "tcp_no_metrics_save",
526 .data = &sysctl_tcp_nometrics_save,
527 .maxlen = sizeof(int),
529 .proc_handler = proc_dointvec,
532 .procname = "tcp_moderate_rcvbuf",
533 .data = &sysctl_tcp_moderate_rcvbuf,
534 .maxlen = sizeof(int),
536 .proc_handler = proc_dointvec,
539 .procname = "tcp_tso_win_divisor",
540 .data = &sysctl_tcp_tso_win_divisor,
541 .maxlen = sizeof(int),
543 .proc_handler = proc_dointvec,
546 .procname = "tcp_congestion_control",
548 .maxlen = TCP_CA_NAME_MAX,
549 .proc_handler = proc_tcp_congestion_control,
552 .procname = "tcp_abc",
553 .data = &sysctl_tcp_abc,
554 .maxlen = sizeof(int),
556 .proc_handler = proc_dointvec,
559 .procname = "tcp_mtu_probing",
560 .data = &sysctl_tcp_mtu_probing,
561 .maxlen = sizeof(int),
563 .proc_handler = proc_dointvec,
566 .procname = "tcp_base_mss",
567 .data = &sysctl_tcp_base_mss,
568 .maxlen = sizeof(int),
570 .proc_handler = proc_dointvec,
573 .procname = "tcp_workaround_signed_windows",
574 .data = &sysctl_tcp_workaround_signed_windows,
575 .maxlen = sizeof(int),
577 .proc_handler = proc_dointvec
579 #ifdef CONFIG_NET_DMA
581 .procname = "tcp_dma_copybreak",
582 .data = &sysctl_tcp_dma_copybreak,
583 .maxlen = sizeof(int),
585 .proc_handler = proc_dointvec
589 .procname = "tcp_slow_start_after_idle",
590 .data = &sysctl_tcp_slow_start_after_idle,
591 .maxlen = sizeof(int),
593 .proc_handler = proc_dointvec
595 #ifdef CONFIG_NETLABEL
597 .procname = "cipso_cache_enable",
598 .data = &cipso_v4_cache_enabled,
599 .maxlen = sizeof(int),
601 .proc_handler = proc_dointvec,
604 .procname = "cipso_cache_bucket_size",
605 .data = &cipso_v4_cache_bucketsize,
606 .maxlen = sizeof(int),
608 .proc_handler = proc_dointvec,
611 .procname = "cipso_rbm_optfmt",
612 .data = &cipso_v4_rbm_optfmt,
613 .maxlen = sizeof(int),
615 .proc_handler = proc_dointvec,
618 .procname = "cipso_rbm_strictvalid",
619 .data = &cipso_v4_rbm_strictvalid,
620 .maxlen = sizeof(int),
622 .proc_handler = proc_dointvec,
624 #endif /* CONFIG_NETLABEL */
626 .procname = "tcp_available_congestion_control",
627 .maxlen = TCP_CA_BUF_MAX,
629 .proc_handler = proc_tcp_available_congestion_control,
632 .procname = "tcp_allowed_congestion_control",
633 .maxlen = TCP_CA_BUF_MAX,
635 .proc_handler = proc_allowed_congestion_control,
638 .procname = "tcp_max_ssthresh",
639 .data = &sysctl_tcp_max_ssthresh,
640 .maxlen = sizeof(int),
642 .proc_handler = proc_dointvec,
645 .procname = "tcp_cookie_size",
646 .data = &sysctl_tcp_cookie_size,
647 .maxlen = sizeof(int),
649 .proc_handler = proc_dointvec
652 .procname = "tcp_thin_linear_timeouts",
653 .data = &sysctl_tcp_thin_linear_timeouts,
654 .maxlen = sizeof(int),
656 .proc_handler = proc_dointvec
659 .procname = "tcp_thin_dupack",
660 .data = &sysctl_tcp_thin_dupack,
661 .maxlen = sizeof(int),
663 .proc_handler = proc_dointvec
666 .procname = "udp_mem",
667 .data = &sysctl_udp_mem,
668 .maxlen = sizeof(sysctl_udp_mem),
670 .proc_handler = proc_doulongvec_minmax,
673 .procname = "udp_rmem_min",
674 .data = &sysctl_udp_rmem_min,
675 .maxlen = sizeof(sysctl_udp_rmem_min),
677 .proc_handler = proc_dointvec_minmax,
681 .procname = "udp_wmem_min",
682 .data = &sysctl_udp_wmem_min,
683 .maxlen = sizeof(sysctl_udp_wmem_min),
685 .proc_handler = proc_dointvec_minmax,
691 static struct ctl_table ipv4_net_table[] = {
693 .procname = "icmp_echo_ignore_all",
694 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
695 .maxlen = sizeof(int),
697 .proc_handler = proc_dointvec
700 .procname = "icmp_echo_ignore_broadcasts",
701 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
702 .maxlen = sizeof(int),
704 .proc_handler = proc_dointvec
707 .procname = "icmp_ignore_bogus_error_responses",
708 .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
709 .maxlen = sizeof(int),
711 .proc_handler = proc_dointvec
714 .procname = "icmp_errors_use_inbound_ifaddr",
715 .data = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
716 .maxlen = sizeof(int),
718 .proc_handler = proc_dointvec
721 .procname = "icmp_ratelimit",
722 .data = &init_net.ipv4.sysctl_icmp_ratelimit,
723 .maxlen = sizeof(int),
725 .proc_handler = proc_dointvec_ms_jiffies,
728 .procname = "icmp_ratemask",
729 .data = &init_net.ipv4.sysctl_icmp_ratemask,
730 .maxlen = sizeof(int),
732 .proc_handler = proc_dointvec
735 .procname = "rt_cache_rebuild_count",
736 .data = &init_net.ipv4.sysctl_rt_cache_rebuild_count,
737 .maxlen = sizeof(int),
739 .proc_handler = proc_dointvec
742 .procname = "ping_group_range",
743 .data = &init_net.ipv4.sysctl_ping_group_range,
744 .maxlen = sizeof(init_net.ipv4.sysctl_ping_group_range),
746 .proc_handler = ipv4_ping_group_range,
749 .procname = "tcp_mem",
750 .maxlen = sizeof(init_net.ipv4.sysctl_tcp_mem),
752 .proc_handler = ipv4_tcp_mem,
757 struct ctl_path net_ipv4_ctl_path[] = {
758 { .procname = "net", },
759 { .procname = "ipv4", },
762 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
764 static __net_init int ipv4_sysctl_init_net(struct net *net)
766 struct ctl_table *table;
769 table = ipv4_net_table;
770 if (!net_eq(net, &init_net)) {
771 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
776 &net->ipv4.sysctl_icmp_echo_ignore_all;
778 &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
780 &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
782 &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
784 &net->ipv4.sysctl_icmp_ratelimit;
786 &net->ipv4.sysctl_icmp_ratemask;
788 &net->ipv4.sysctl_rt_cache_rebuild_count;
790 &net->ipv4.sysctl_ping_group_range;
795 * Sane defaults - nobody may create ping sockets.
796 * Boot scripts should set this to distro-specific group.
798 net->ipv4.sysctl_ping_group_range[0] = 1;
799 net->ipv4.sysctl_ping_group_range[1] = 0;
801 net->ipv4.sysctl_rt_cache_rebuild_count = 4;
803 limit = nr_free_buffer_pages() / 8;
804 limit = max(limit, 128UL);
805 net->ipv4.sysctl_tcp_mem[0] = limit / 4 * 3;
806 net->ipv4.sysctl_tcp_mem[1] = limit;
807 net->ipv4.sysctl_tcp_mem[2] = net->ipv4.sysctl_tcp_mem[0] * 2;
809 net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
810 net_ipv4_ctl_path, table);
811 if (net->ipv4.ipv4_hdr == NULL)
817 if (!net_eq(net, &init_net))
823 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
825 struct ctl_table *table;
827 table = net->ipv4.ipv4_hdr->ctl_table_arg;
828 unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
832 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
833 .init = ipv4_sysctl_init_net,
834 .exit = ipv4_sysctl_exit_net,
837 static __init int sysctl_ipv4_init(void)
839 struct ctl_table_header *hdr;
842 for (i = ipv4_table; i->procname; i++) {
843 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
844 i->data = sysctl_local_reserved_ports;
851 hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
855 if (register_pernet_subsys(&ipv4_sysctl_ops)) {
856 unregister_sysctl_table(hdr);
863 __initcall(sysctl_ipv4_init);