d96c1da4b17cf97790bb2a426abbe5eb4582356d
[linux-3.10.git] / net / ipv4 / sysctl_net_ipv4.c
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 <net/snmp.h>
17 #include <net/icmp.h>
18 #include <net/ip.h>
19 #include <net/route.h>
20 #include <net/tcp.h>
21 #include <net/udp.h>
22 #include <net/cipso_ipv4.h>
23 #include <net/inet_frag.h>
24
25 static int zero;
26 static int tcp_retr1_max = 255;
27 static int ip_local_port_range_min[] = { 1, 1 };
28 static int ip_local_port_range_max[] = { 65535, 65535 };
29
30 /* Update system visible IP port range */
31 static void set_local_port_range(int range[2])
32 {
33         write_seqlock(&sysctl_local_ports.lock);
34         sysctl_local_ports.range[0] = range[0];
35         sysctl_local_ports.range[1] = range[1];
36         write_sequnlock(&sysctl_local_ports.lock);
37 }
38
39 /* Validate changes from /proc interface. */
40 static int ipv4_local_port_range(ctl_table *table, int write,
41                                  void __user *buffer,
42                                  size_t *lenp, loff_t *ppos)
43 {
44         int ret;
45         int range[2];
46         ctl_table tmp = {
47                 .data = &range,
48                 .maxlen = sizeof(range),
49                 .mode = table->mode,
50                 .extra1 = &ip_local_port_range_min,
51                 .extra2 = &ip_local_port_range_max,
52         };
53
54         inet_get_local_port_range(range, range + 1);
55         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
56
57         if (write && ret == 0) {
58                 if (range[1] < range[0])
59                         ret = -EINVAL;
60                 else
61                         set_local_port_range(range);
62         }
63
64         return ret;
65 }
66
67 static int proc_tcp_congestion_control(ctl_table *ctl, int write,
68                                        void __user *buffer, size_t *lenp, loff_t *ppos)
69 {
70         char val[TCP_CA_NAME_MAX];
71         ctl_table tbl = {
72                 .data = val,
73                 .maxlen = TCP_CA_NAME_MAX,
74         };
75         int ret;
76
77         tcp_get_default_congestion_control(val);
78
79         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
80         if (write && ret == 0)
81                 ret = tcp_set_default_congestion_control(val);
82         return ret;
83 }
84
85 static int proc_tcp_available_congestion_control(ctl_table *ctl,
86                                                  int write,
87                                                  void __user *buffer, size_t *lenp,
88                                                  loff_t *ppos)
89 {
90         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
91         int ret;
92
93         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
94         if (!tbl.data)
95                 return -ENOMEM;
96         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
97         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
98         kfree(tbl.data);
99         return ret;
100 }
101
102 static int proc_allowed_congestion_control(ctl_table *ctl,
103                                            int write,
104                                            void __user *buffer, size_t *lenp,
105                                            loff_t *ppos)
106 {
107         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
108         int ret;
109
110         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
111         if (!tbl.data)
112                 return -ENOMEM;
113
114         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
115         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
116         if (write && ret == 0)
117                 ret = tcp_set_allowed_congestion_control(tbl.data);
118         kfree(tbl.data);
119         return ret;
120 }
121
122 static struct ctl_table ipv4_table[] = {
123         {
124                 .procname       = "tcp_timestamps",
125                 .data           = &sysctl_tcp_timestamps,
126                 .maxlen         = sizeof(int),
127                 .mode           = 0644,
128                 .proc_handler   = proc_dointvec
129         },
130         {
131                 .procname       = "tcp_window_scaling",
132                 .data           = &sysctl_tcp_window_scaling,
133                 .maxlen         = sizeof(int),
134                 .mode           = 0644,
135                 .proc_handler   = proc_dointvec
136         },
137         {
138                 .procname       = "tcp_sack",
139                 .data           = &sysctl_tcp_sack,
140                 .maxlen         = sizeof(int),
141                 .mode           = 0644,
142                 .proc_handler   = proc_dointvec
143         },
144         {
145                 .procname       = "tcp_retrans_collapse",
146                 .data           = &sysctl_tcp_retrans_collapse,
147                 .maxlen         = sizeof(int),
148                 .mode           = 0644,
149                 .proc_handler   = proc_dointvec
150         },
151         {
152                 .procname       = "ip_default_ttl",
153                 .data           = &sysctl_ip_default_ttl,
154                 .maxlen         = sizeof(int),
155                 .mode           = 0644,
156                 .proc_handler   = ipv4_doint_and_flush,
157                 .extra2         = &init_net,
158         },
159         {
160                 .procname       = "ip_no_pmtu_disc",
161                 .data           = &ipv4_config.no_pmtu_disc,
162                 .maxlen         = sizeof(int),
163                 .mode           = 0644,
164                 .proc_handler   = proc_dointvec
165         },
166         {
167                 .procname       = "ip_nonlocal_bind",
168                 .data           = &sysctl_ip_nonlocal_bind,
169                 .maxlen         = sizeof(int),
170                 .mode           = 0644,
171                 .proc_handler   = proc_dointvec
172         },
173         {
174                 .procname       = "tcp_syn_retries",
175                 .data           = &sysctl_tcp_syn_retries,
176                 .maxlen         = sizeof(int),
177                 .mode           = 0644,
178                 .proc_handler   = proc_dointvec
179         },
180         {
181                 .procname       = "tcp_synack_retries",
182                 .data           = &sysctl_tcp_synack_retries,
183                 .maxlen         = sizeof(int),
184                 .mode           = 0644,
185                 .proc_handler   = proc_dointvec
186         },
187         {
188                 .procname       = "tcp_max_orphans",
189                 .data           = &sysctl_tcp_max_orphans,
190                 .maxlen         = sizeof(int),
191                 .mode           = 0644,
192                 .proc_handler   = proc_dointvec
193         },
194         {
195                 .procname       = "tcp_max_tw_buckets",
196                 .data           = &tcp_death_row.sysctl_max_tw_buckets,
197                 .maxlen         = sizeof(int),
198                 .mode           = 0644,
199                 .proc_handler   = proc_dointvec
200         },
201         {
202                 .procname       = "ip_dynaddr",
203                 .data           = &sysctl_ip_dynaddr,
204                 .maxlen         = sizeof(int),
205                 .mode           = 0644,
206                 .proc_handler   = proc_dointvec
207         },
208         {
209                 .procname       = "tcp_keepalive_time",
210                 .data           = &sysctl_tcp_keepalive_time,
211                 .maxlen         = sizeof(int),
212                 .mode           = 0644,
213                 .proc_handler   = proc_dointvec_jiffies,
214         },
215         {
216                 .procname       = "tcp_keepalive_probes",
217                 .data           = &sysctl_tcp_keepalive_probes,
218                 .maxlen         = sizeof(int),
219                 .mode           = 0644,
220                 .proc_handler   = proc_dointvec
221         },
222         {
223                 .procname       = "tcp_keepalive_intvl",
224                 .data           = &sysctl_tcp_keepalive_intvl,
225                 .maxlen         = sizeof(int),
226                 .mode           = 0644,
227                 .proc_handler   = proc_dointvec_jiffies,
228         },
229         {
230                 .procname       = "tcp_retries1",
231                 .data           = &sysctl_tcp_retries1,
232                 .maxlen         = sizeof(int),
233                 .mode           = 0644,
234                 .proc_handler   = proc_dointvec_minmax,
235                 .extra2         = &tcp_retr1_max
236         },
237         {
238                 .procname       = "tcp_retries2",
239                 .data           = &sysctl_tcp_retries2,
240                 .maxlen         = sizeof(int),
241                 .mode           = 0644,
242                 .proc_handler   = proc_dointvec
243         },
244         {
245                 .procname       = "tcp_fin_timeout",
246                 .data           = &sysctl_tcp_fin_timeout,
247                 .maxlen         = sizeof(int),
248                 .mode           = 0644,
249                 .proc_handler   = proc_dointvec_jiffies,
250         },
251 #ifdef CONFIG_SYN_COOKIES
252         {
253                 .procname       = "tcp_syncookies",
254                 .data           = &sysctl_tcp_syncookies,
255                 .maxlen         = sizeof(int),
256                 .mode           = 0644,
257                 .proc_handler   = proc_dointvec
258         },
259 #endif
260         {
261                 .procname       = "tcp_tw_recycle",
262                 .data           = &tcp_death_row.sysctl_tw_recycle,
263                 .maxlen         = sizeof(int),
264                 .mode           = 0644,
265                 .proc_handler   = proc_dointvec
266         },
267         {
268                 .procname       = "tcp_abort_on_overflow",
269                 .data           = &sysctl_tcp_abort_on_overflow,
270                 .maxlen         = sizeof(int),
271                 .mode           = 0644,
272                 .proc_handler   = proc_dointvec
273         },
274         {
275                 .procname       = "tcp_stdurg",
276                 .data           = &sysctl_tcp_stdurg,
277                 .maxlen         = sizeof(int),
278                 .mode           = 0644,
279                 .proc_handler   = proc_dointvec
280         },
281         {
282                 .procname       = "tcp_rfc1337",
283                 .data           = &sysctl_tcp_rfc1337,
284                 .maxlen         = sizeof(int),
285                 .mode           = 0644,
286                 .proc_handler   = proc_dointvec
287         },
288         {
289                 .procname       = "tcp_max_syn_backlog",
290                 .data           = &sysctl_max_syn_backlog,
291                 .maxlen         = sizeof(int),
292                 .mode           = 0644,
293                 .proc_handler   = proc_dointvec
294         },
295         {
296                 .procname       = "ip_local_port_range",
297                 .data           = &sysctl_local_ports.range,
298                 .maxlen         = sizeof(sysctl_local_ports.range),
299                 .mode           = 0644,
300                 .proc_handler   = ipv4_local_port_range,
301         },
302         {
303                 .procname       = "ip_local_reserved_ports",
304                 .data           = NULL, /* initialized in sysctl_ipv4_init */
305                 .maxlen         = 65536,
306                 .mode           = 0644,
307                 .proc_handler   = proc_do_large_bitmap,
308         },
309 #ifdef CONFIG_IP_MULTICAST
310         {
311                 .procname       = "igmp_max_memberships",
312                 .data           = &sysctl_igmp_max_memberships,
313                 .maxlen         = sizeof(int),
314                 .mode           = 0644,
315                 .proc_handler   = proc_dointvec
316         },
317
318 #endif
319         {
320                 .procname       = "igmp_max_msf",
321                 .data           = &sysctl_igmp_max_msf,
322                 .maxlen         = sizeof(int),
323                 .mode           = 0644,
324                 .proc_handler   = proc_dointvec
325         },
326         {
327                 .procname       = "inet_peer_threshold",
328                 .data           = &inet_peer_threshold,
329                 .maxlen         = sizeof(int),
330                 .mode           = 0644,
331                 .proc_handler   = proc_dointvec
332         },
333         {
334                 .procname       = "inet_peer_minttl",
335                 .data           = &inet_peer_minttl,
336                 .maxlen         = sizeof(int),
337                 .mode           = 0644,
338                 .proc_handler   = proc_dointvec_jiffies,
339         },
340         {
341                 .procname       = "inet_peer_maxttl",
342                 .data           = &inet_peer_maxttl,
343                 .maxlen         = sizeof(int),
344                 .mode           = 0644,
345                 .proc_handler   = proc_dointvec_jiffies,
346         },
347         {
348                 .procname       = "inet_peer_gc_mintime",
349                 .data           = &inet_peer_gc_mintime,
350                 .maxlen         = sizeof(int),
351                 .mode           = 0644,
352                 .proc_handler   = proc_dointvec_jiffies,
353         },
354         {
355                 .procname       = "inet_peer_gc_maxtime",
356                 .data           = &inet_peer_gc_maxtime,
357                 .maxlen         = sizeof(int),
358                 .mode           = 0644,
359                 .proc_handler   = proc_dointvec_jiffies,
360         },
361         {
362                 .procname       = "tcp_orphan_retries",
363                 .data           = &sysctl_tcp_orphan_retries,
364                 .maxlen         = sizeof(int),
365                 .mode           = 0644,
366                 .proc_handler   = proc_dointvec
367         },
368         {
369                 .procname       = "tcp_fack",
370                 .data           = &sysctl_tcp_fack,
371                 .maxlen         = sizeof(int),
372                 .mode           = 0644,
373                 .proc_handler   = proc_dointvec
374         },
375         {
376                 .procname       = "tcp_reordering",
377                 .data           = &sysctl_tcp_reordering,
378                 .maxlen         = sizeof(int),
379                 .mode           = 0644,
380                 .proc_handler   = proc_dointvec
381         },
382         {
383                 .procname       = "tcp_ecn",
384                 .data           = &sysctl_tcp_ecn,
385                 .maxlen         = sizeof(int),
386                 .mode           = 0644,
387                 .proc_handler   = proc_dointvec
388         },
389         {
390                 .procname       = "tcp_dsack",
391                 .data           = &sysctl_tcp_dsack,
392                 .maxlen         = sizeof(int),
393                 .mode           = 0644,
394                 .proc_handler   = proc_dointvec
395         },
396         {
397                 .procname       = "tcp_mem",
398                 .data           = &sysctl_tcp_mem,
399                 .maxlen         = sizeof(sysctl_tcp_mem),
400                 .mode           = 0644,
401                 .proc_handler   = proc_dointvec
402         },
403         {
404                 .procname       = "tcp_wmem",
405                 .data           = &sysctl_tcp_wmem,
406                 .maxlen         = sizeof(sysctl_tcp_wmem),
407                 .mode           = 0644,
408                 .proc_handler   = proc_dointvec
409         },
410         {
411                 .procname       = "tcp_rmem",
412                 .data           = &sysctl_tcp_rmem,
413                 .maxlen         = sizeof(sysctl_tcp_rmem),
414                 .mode           = 0644,
415                 .proc_handler   = proc_dointvec
416         },
417         {
418                 .procname       = "tcp_app_win",
419                 .data           = &sysctl_tcp_app_win,
420                 .maxlen         = sizeof(int),
421                 .mode           = 0644,
422                 .proc_handler   = proc_dointvec
423         },
424         {
425                 .procname       = "tcp_adv_win_scale",
426                 .data           = &sysctl_tcp_adv_win_scale,
427                 .maxlen         = sizeof(int),
428                 .mode           = 0644,
429                 .proc_handler   = proc_dointvec
430         },
431         {
432                 .procname       = "tcp_tw_reuse",
433                 .data           = &sysctl_tcp_tw_reuse,
434                 .maxlen         = sizeof(int),
435                 .mode           = 0644,
436                 .proc_handler   = proc_dointvec
437         },
438         {
439                 .procname       = "tcp_frto",
440                 .data           = &sysctl_tcp_frto,
441                 .maxlen         = sizeof(int),
442                 .mode           = 0644,
443                 .proc_handler   = proc_dointvec
444         },
445         {
446                 .procname       = "tcp_frto_response",
447                 .data           = &sysctl_tcp_frto_response,
448                 .maxlen         = sizeof(int),
449                 .mode           = 0644,
450                 .proc_handler   = proc_dointvec
451         },
452         {
453                 .procname       = "tcp_low_latency",
454                 .data           = &sysctl_tcp_low_latency,
455                 .maxlen         = sizeof(int),
456                 .mode           = 0644,
457                 .proc_handler   = proc_dointvec
458         },
459         {
460                 .procname       = "tcp_no_metrics_save",
461                 .data           = &sysctl_tcp_nometrics_save,
462                 .maxlen         = sizeof(int),
463                 .mode           = 0644,
464                 .proc_handler   = proc_dointvec,
465         },
466         {
467                 .procname       = "tcp_moderate_rcvbuf",
468                 .data           = &sysctl_tcp_moderate_rcvbuf,
469                 .maxlen         = sizeof(int),
470                 .mode           = 0644,
471                 .proc_handler   = proc_dointvec,
472         },
473         {
474                 .procname       = "tcp_tso_win_divisor",
475                 .data           = &sysctl_tcp_tso_win_divisor,
476                 .maxlen         = sizeof(int),
477                 .mode           = 0644,
478                 .proc_handler   = proc_dointvec,
479         },
480         {
481                 .procname       = "tcp_congestion_control",
482                 .mode           = 0644,
483                 .maxlen         = TCP_CA_NAME_MAX,
484                 .proc_handler   = proc_tcp_congestion_control,
485         },
486         {
487                 .procname       = "tcp_abc",
488                 .data           = &sysctl_tcp_abc,
489                 .maxlen         = sizeof(int),
490                 .mode           = 0644,
491                 .proc_handler   = proc_dointvec,
492         },
493         {
494                 .procname       = "tcp_mtu_probing",
495                 .data           = &sysctl_tcp_mtu_probing,
496                 .maxlen         = sizeof(int),
497                 .mode           = 0644,
498                 .proc_handler   = proc_dointvec,
499         },
500         {
501                 .procname       = "tcp_base_mss",
502                 .data           = &sysctl_tcp_base_mss,
503                 .maxlen         = sizeof(int),
504                 .mode           = 0644,
505                 .proc_handler   = proc_dointvec,
506         },
507         {
508                 .procname       = "tcp_workaround_signed_windows",
509                 .data           = &sysctl_tcp_workaround_signed_windows,
510                 .maxlen         = sizeof(int),
511                 .mode           = 0644,
512                 .proc_handler   = proc_dointvec
513         },
514 #ifdef CONFIG_NET_DMA
515         {
516                 .procname       = "tcp_dma_copybreak",
517                 .data           = &sysctl_tcp_dma_copybreak,
518                 .maxlen         = sizeof(int),
519                 .mode           = 0644,
520                 .proc_handler   = proc_dointvec
521         },
522 #endif
523         {
524                 .procname       = "tcp_slow_start_after_idle",
525                 .data           = &sysctl_tcp_slow_start_after_idle,
526                 .maxlen         = sizeof(int),
527                 .mode           = 0644,
528                 .proc_handler   = proc_dointvec
529         },
530 #ifdef CONFIG_NETLABEL
531         {
532                 .procname       = "cipso_cache_enable",
533                 .data           = &cipso_v4_cache_enabled,
534                 .maxlen         = sizeof(int),
535                 .mode           = 0644,
536                 .proc_handler   = proc_dointvec,
537         },
538         {
539                 .procname       = "cipso_cache_bucket_size",
540                 .data           = &cipso_v4_cache_bucketsize,
541                 .maxlen         = sizeof(int),
542                 .mode           = 0644,
543                 .proc_handler   = proc_dointvec,
544         },
545         {
546                 .procname       = "cipso_rbm_optfmt",
547                 .data           = &cipso_v4_rbm_optfmt,
548                 .maxlen         = sizeof(int),
549                 .mode           = 0644,
550                 .proc_handler   = proc_dointvec,
551         },
552         {
553                 .procname       = "cipso_rbm_strictvalid",
554                 .data           = &cipso_v4_rbm_strictvalid,
555                 .maxlen         = sizeof(int),
556                 .mode           = 0644,
557                 .proc_handler   = proc_dointvec,
558         },
559 #endif /* CONFIG_NETLABEL */
560         {
561                 .procname       = "tcp_available_congestion_control",
562                 .maxlen         = TCP_CA_BUF_MAX,
563                 .mode           = 0444,
564                 .proc_handler   = proc_tcp_available_congestion_control,
565         },
566         {
567                 .procname       = "tcp_allowed_congestion_control",
568                 .maxlen         = TCP_CA_BUF_MAX,
569                 .mode           = 0644,
570                 .proc_handler   = proc_allowed_congestion_control,
571         },
572         {
573                 .procname       = "tcp_max_ssthresh",
574                 .data           = &sysctl_tcp_max_ssthresh,
575                 .maxlen         = sizeof(int),
576                 .mode           = 0644,
577                 .proc_handler   = proc_dointvec,
578         },
579         {
580                 .procname       = "tcp_cookie_size",
581                 .data           = &sysctl_tcp_cookie_size,
582                 .maxlen         = sizeof(int),
583                 .mode           = 0644,
584                 .proc_handler   = proc_dointvec
585         },
586         {
587                 .procname       = "tcp_thin_linear_timeouts",
588                 .data           = &sysctl_tcp_thin_linear_timeouts,
589                 .maxlen         = sizeof(int),
590                 .mode           = 0644,
591                 .proc_handler   = proc_dointvec
592         },
593         {
594                 .procname       = "tcp_thin_dupack",
595                 .data           = &sysctl_tcp_thin_dupack,
596                 .maxlen         = sizeof(int),
597                 .mode           = 0644,
598                 .proc_handler   = proc_dointvec
599         },
600         {
601                 .procname       = "udp_mem",
602                 .data           = &sysctl_udp_mem,
603                 .maxlen         = sizeof(sysctl_udp_mem),
604                 .mode           = 0644,
605                 .proc_handler   = proc_dointvec_minmax,
606                 .extra1         = &zero
607         },
608         {
609                 .procname       = "udp_rmem_min",
610                 .data           = &sysctl_udp_rmem_min,
611                 .maxlen         = sizeof(sysctl_udp_rmem_min),
612                 .mode           = 0644,
613                 .proc_handler   = proc_dointvec_minmax,
614                 .extra1         = &zero
615         },
616         {
617                 .procname       = "udp_wmem_min",
618                 .data           = &sysctl_udp_wmem_min,
619                 .maxlen         = sizeof(sysctl_udp_wmem_min),
620                 .mode           = 0644,
621                 .proc_handler   = proc_dointvec_minmax,
622                 .extra1         = &zero
623         },
624         { }
625 };
626
627 static struct ctl_table ipv4_net_table[] = {
628         {
629                 .procname       = "icmp_echo_ignore_all",
630                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
631                 .maxlen         = sizeof(int),
632                 .mode           = 0644,
633                 .proc_handler   = proc_dointvec
634         },
635         {
636                 .procname       = "icmp_echo_ignore_broadcasts",
637                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
638                 .maxlen         = sizeof(int),
639                 .mode           = 0644,
640                 .proc_handler   = proc_dointvec
641         },
642         {
643                 .procname       = "icmp_ignore_bogus_error_responses",
644                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
645                 .maxlen         = sizeof(int),
646                 .mode           = 0644,
647                 .proc_handler   = proc_dointvec
648         },
649         {
650                 .procname       = "icmp_errors_use_inbound_ifaddr",
651                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
652                 .maxlen         = sizeof(int),
653                 .mode           = 0644,
654                 .proc_handler   = proc_dointvec
655         },
656         {
657                 .procname       = "icmp_ratelimit",
658                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
659                 .maxlen         = sizeof(int),
660                 .mode           = 0644,
661                 .proc_handler   = proc_dointvec_ms_jiffies,
662         },
663         {
664                 .procname       = "icmp_ratemask",
665                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
666                 .maxlen         = sizeof(int),
667                 .mode           = 0644,
668                 .proc_handler   = proc_dointvec
669         },
670         {
671                 .procname       = "rt_cache_rebuild_count",
672                 .data           = &init_net.ipv4.sysctl_rt_cache_rebuild_count,
673                 .maxlen         = sizeof(int),
674                 .mode           = 0644,
675                 .proc_handler   = proc_dointvec
676         },
677         { }
678 };
679
680 struct ctl_path net_ipv4_ctl_path[] = {
681         { .procname = "net", },
682         { .procname = "ipv4", },
683         { },
684 };
685 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
686
687 static __net_init int ipv4_sysctl_init_net(struct net *net)
688 {
689         struct ctl_table *table;
690
691         table = ipv4_net_table;
692         if (!net_eq(net, &init_net)) {
693                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
694                 if (table == NULL)
695                         goto err_alloc;
696
697                 table[0].data =
698                         &net->ipv4.sysctl_icmp_echo_ignore_all;
699                 table[1].data =
700                         &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
701                 table[2].data =
702                         &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
703                 table[3].data =
704                         &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
705                 table[4].data =
706                         &net->ipv4.sysctl_icmp_ratelimit;
707                 table[5].data =
708                         &net->ipv4.sysctl_icmp_ratemask;
709                 table[6].data =
710                         &net->ipv4.sysctl_rt_cache_rebuild_count;
711         }
712
713         net->ipv4.sysctl_rt_cache_rebuild_count = 4;
714
715         net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
716                         net_ipv4_ctl_path, table);
717         if (net->ipv4.ipv4_hdr == NULL)
718                 goto err_reg;
719
720         return 0;
721
722 err_reg:
723         if (!net_eq(net, &init_net))
724                 kfree(table);
725 err_alloc:
726         return -ENOMEM;
727 }
728
729 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
730 {
731         struct ctl_table *table;
732
733         table = net->ipv4.ipv4_hdr->ctl_table_arg;
734         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
735         kfree(table);
736 }
737
738 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
739         .init = ipv4_sysctl_init_net,
740         .exit = ipv4_sysctl_exit_net,
741 };
742
743 static __init int sysctl_ipv4_init(void)
744 {
745         struct ctl_table_header *hdr;
746         struct ctl_table *i;
747
748         for (i = ipv4_table; i->procname; i++) {
749                 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
750                         i->data = sysctl_local_reserved_ports;
751                         break;
752                 }
753         }
754         if (!i->procname)
755                 return -EINVAL;
756
757         hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
758         if (hdr == NULL)
759                 return -ENOMEM;
760
761         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
762                 unregister_sysctl_table(hdr);
763                 return -ENOMEM;
764         }
765
766         return 0;
767 }
768
769 __initcall(sysctl_ipv4_init);