xref: /openbmc/linux/net/ipv4/sysctl_net_ipv4.c (revision 545e4006)
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 <net/snmp.h>
16 #include <net/icmp.h>
17 #include <net/ip.h>
18 #include <net/route.h>
19 #include <net/tcp.h>
20 #include <net/udp.h>
21 #include <net/cipso_ipv4.h>
22 #include <net/inet_frag.h>
23 
24 static int zero;
25 static int tcp_retr1_max = 255;
26 static int ip_local_port_range_min[] = { 1, 1 };
27 static int ip_local_port_range_max[] = { 65535, 65535 };
28 
29 extern seqlock_t sysctl_port_range_lock;
30 extern int sysctl_local_port_range[2];
31 
32 /* Update system visible IP port range */
33 static void set_local_port_range(int range[2])
34 {
35 	write_seqlock(&sysctl_port_range_lock);
36 	sysctl_local_port_range[0] = range[0];
37 	sysctl_local_port_range[1] = range[1];
38 	write_sequnlock(&sysctl_port_range_lock);
39 }
40 
41 /* Validate changes from /proc interface. */
42 static int ipv4_local_port_range(ctl_table *table, int write, struct file *filp,
43 				 void __user *buffer,
44 				 size_t *lenp, loff_t *ppos)
45 {
46 	int ret;
47 	int range[2] = { sysctl_local_port_range[0],
48 			 sysctl_local_port_range[1] };
49 	ctl_table tmp = {
50 		.data = &range,
51 		.maxlen = sizeof(range),
52 		.mode = table->mode,
53 		.extra1 = &ip_local_port_range_min,
54 		.extra2 = &ip_local_port_range_max,
55 	};
56 
57 	ret = proc_dointvec_minmax(&tmp, write, filp, buffer, lenp, ppos);
58 
59 	if (write && ret == 0) {
60 		if (range[1] < range[0])
61 			ret = -EINVAL;
62 		else
63 			set_local_port_range(range);
64 	}
65 
66 	return ret;
67 }
68 
69 /* Validate changes from sysctl interface. */
70 static int ipv4_sysctl_local_port_range(ctl_table *table, int __user *name,
71 					 int nlen, void __user *oldval,
72 					 size_t __user *oldlenp,
73 					void __user *newval, size_t newlen)
74 {
75 	int ret;
76 	int range[2] = { sysctl_local_port_range[0],
77 			 sysctl_local_port_range[1] };
78 	ctl_table tmp = {
79 		.data = &range,
80 		.maxlen = sizeof(range),
81 		.mode = table->mode,
82 		.extra1 = &ip_local_port_range_min,
83 		.extra2 = &ip_local_port_range_max,
84 	};
85 
86 	ret = sysctl_intvec(&tmp, name, nlen, oldval, oldlenp, newval, newlen);
87 	if (ret == 0 && newval && newlen) {
88 		if (range[1] < range[0])
89 			ret = -EINVAL;
90 		else
91 			set_local_port_range(range);
92 	}
93 	return ret;
94 }
95 
96 
97 static int proc_tcp_congestion_control(ctl_table *ctl, int write, struct file * filp,
98 				       void __user *buffer, size_t *lenp, loff_t *ppos)
99 {
100 	char val[TCP_CA_NAME_MAX];
101 	ctl_table tbl = {
102 		.data = val,
103 		.maxlen = TCP_CA_NAME_MAX,
104 	};
105 	int ret;
106 
107 	tcp_get_default_congestion_control(val);
108 
109 	ret = proc_dostring(&tbl, write, filp, buffer, lenp, ppos);
110 	if (write && ret == 0)
111 		ret = tcp_set_default_congestion_control(val);
112 	return ret;
113 }
114 
115 static int sysctl_tcp_congestion_control(ctl_table *table, int __user *name,
116 					 int nlen, void __user *oldval,
117 					 size_t __user *oldlenp,
118 					 void __user *newval, size_t newlen)
119 {
120 	char val[TCP_CA_NAME_MAX];
121 	ctl_table tbl = {
122 		.data = val,
123 		.maxlen = TCP_CA_NAME_MAX,
124 	};
125 	int ret;
126 
127 	tcp_get_default_congestion_control(val);
128 	ret = sysctl_string(&tbl, name, nlen, oldval, oldlenp, newval, newlen);
129 	if (ret == 1 && newval && newlen)
130 		ret = tcp_set_default_congestion_control(val);
131 	return ret;
132 }
133 
134 static int proc_tcp_available_congestion_control(ctl_table *ctl,
135 						 int write, struct file * filp,
136 						 void __user *buffer, size_t *lenp,
137 						 loff_t *ppos)
138 {
139 	ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
140 	int ret;
141 
142 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
143 	if (!tbl.data)
144 		return -ENOMEM;
145 	tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
146 	ret = proc_dostring(&tbl, write, filp, buffer, lenp, ppos);
147 	kfree(tbl.data);
148 	return ret;
149 }
150 
151 static int proc_allowed_congestion_control(ctl_table *ctl,
152 					   int write, struct file * filp,
153 					   void __user *buffer, size_t *lenp,
154 					   loff_t *ppos)
155 {
156 	ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
157 	int ret;
158 
159 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
160 	if (!tbl.data)
161 		return -ENOMEM;
162 
163 	tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
164 	ret = proc_dostring(&tbl, write, filp, buffer, lenp, ppos);
165 	if (write && ret == 0)
166 		ret = tcp_set_allowed_congestion_control(tbl.data);
167 	kfree(tbl.data);
168 	return ret;
169 }
170 
171 static int strategy_allowed_congestion_control(ctl_table *table, int __user *name,
172 					       int nlen, void __user *oldval,
173 					       size_t __user *oldlenp,
174 					       void __user *newval,
175 					       size_t newlen)
176 {
177 	ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
178 	int ret;
179 
180 	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
181 	if (!tbl.data)
182 		return -ENOMEM;
183 
184 	tcp_get_available_congestion_control(tbl.data, tbl.maxlen);
185 	ret = sysctl_string(&tbl, name, nlen, oldval, oldlenp, newval, newlen);
186 	if (ret == 1 && newval && newlen)
187 		ret = tcp_set_allowed_congestion_control(tbl.data);
188 	kfree(tbl.data);
189 
190 	return ret;
191 
192 }
193 
194 static struct ctl_table ipv4_table[] = {
195 	{
196 		.ctl_name	= NET_IPV4_TCP_TIMESTAMPS,
197 		.procname	= "tcp_timestamps",
198 		.data		= &sysctl_tcp_timestamps,
199 		.maxlen		= sizeof(int),
200 		.mode		= 0644,
201 		.proc_handler	= &proc_dointvec
202 	},
203 	{
204 		.ctl_name	= NET_IPV4_TCP_WINDOW_SCALING,
205 		.procname	= "tcp_window_scaling",
206 		.data		= &sysctl_tcp_window_scaling,
207 		.maxlen		= sizeof(int),
208 		.mode		= 0644,
209 		.proc_handler	= &proc_dointvec
210 	},
211 	{
212 		.ctl_name	= NET_IPV4_TCP_SACK,
213 		.procname	= "tcp_sack",
214 		.data		= &sysctl_tcp_sack,
215 		.maxlen		= sizeof(int),
216 		.mode		= 0644,
217 		.proc_handler	= &proc_dointvec
218 	},
219 	{
220 		.ctl_name	= NET_IPV4_TCP_RETRANS_COLLAPSE,
221 		.procname	= "tcp_retrans_collapse",
222 		.data		= &sysctl_tcp_retrans_collapse,
223 		.maxlen		= sizeof(int),
224 		.mode		= 0644,
225 		.proc_handler	= &proc_dointvec
226 	},
227 	{
228 		.ctl_name	= NET_IPV4_DEFAULT_TTL,
229 		.procname	= "ip_default_ttl",
230 		.data		= &sysctl_ip_default_ttl,
231 		.maxlen		= sizeof(int),
232 		.mode		= 0644,
233 		.proc_handler	= &ipv4_doint_and_flush,
234 		.strategy	= &ipv4_doint_and_flush_strategy,
235 	},
236 	{
237 		.ctl_name	= NET_IPV4_NO_PMTU_DISC,
238 		.procname	= "ip_no_pmtu_disc",
239 		.data		= &ipv4_config.no_pmtu_disc,
240 		.maxlen		= sizeof(int),
241 		.mode		= 0644,
242 		.proc_handler	= &proc_dointvec
243 	},
244 	{
245 		.ctl_name	= NET_IPV4_NONLOCAL_BIND,
246 		.procname	= "ip_nonlocal_bind",
247 		.data		= &sysctl_ip_nonlocal_bind,
248 		.maxlen		= sizeof(int),
249 		.mode		= 0644,
250 		.proc_handler	= &proc_dointvec
251 	},
252 	{
253 		.ctl_name	= NET_IPV4_TCP_SYN_RETRIES,
254 		.procname	= "tcp_syn_retries",
255 		.data		= &sysctl_tcp_syn_retries,
256 		.maxlen		= sizeof(int),
257 		.mode		= 0644,
258 		.proc_handler	= &proc_dointvec
259 	},
260 	{
261 		.ctl_name	= NET_TCP_SYNACK_RETRIES,
262 		.procname	= "tcp_synack_retries",
263 		.data		= &sysctl_tcp_synack_retries,
264 		.maxlen		= sizeof(int),
265 		.mode		= 0644,
266 		.proc_handler	= &proc_dointvec
267 	},
268 	{
269 		.ctl_name	= NET_TCP_MAX_ORPHANS,
270 		.procname	= "tcp_max_orphans",
271 		.data		= &sysctl_tcp_max_orphans,
272 		.maxlen		= sizeof(int),
273 		.mode		= 0644,
274 		.proc_handler	= &proc_dointvec
275 	},
276 	{
277 		.ctl_name	= NET_TCP_MAX_TW_BUCKETS,
278 		.procname	= "tcp_max_tw_buckets",
279 		.data		= &tcp_death_row.sysctl_max_tw_buckets,
280 		.maxlen		= sizeof(int),
281 		.mode		= 0644,
282 		.proc_handler	= &proc_dointvec
283 	},
284 	{
285 		.ctl_name	= NET_IPV4_DYNADDR,
286 		.procname	= "ip_dynaddr",
287 		.data		= &sysctl_ip_dynaddr,
288 		.maxlen		= sizeof(int),
289 		.mode		= 0644,
290 		.proc_handler	= &proc_dointvec
291 	},
292 	{
293 		.ctl_name	= NET_IPV4_TCP_KEEPALIVE_TIME,
294 		.procname	= "tcp_keepalive_time",
295 		.data		= &sysctl_tcp_keepalive_time,
296 		.maxlen		= sizeof(int),
297 		.mode		= 0644,
298 		.proc_handler	= &proc_dointvec_jiffies,
299 		.strategy	= &sysctl_jiffies
300 	},
301 	{
302 		.ctl_name	= NET_IPV4_TCP_KEEPALIVE_PROBES,
303 		.procname	= "tcp_keepalive_probes",
304 		.data		= &sysctl_tcp_keepalive_probes,
305 		.maxlen		= sizeof(int),
306 		.mode		= 0644,
307 		.proc_handler	= &proc_dointvec
308 	},
309 	{
310 		.ctl_name	= NET_IPV4_TCP_KEEPALIVE_INTVL,
311 		.procname	= "tcp_keepalive_intvl",
312 		.data		= &sysctl_tcp_keepalive_intvl,
313 		.maxlen		= sizeof(int),
314 		.mode		= 0644,
315 		.proc_handler	= &proc_dointvec_jiffies,
316 		.strategy	= &sysctl_jiffies
317 	},
318 	{
319 		.ctl_name	= NET_IPV4_TCP_RETRIES1,
320 		.procname	= "tcp_retries1",
321 		.data		= &sysctl_tcp_retries1,
322 		.maxlen		= sizeof(int),
323 		.mode		= 0644,
324 		.proc_handler	= &proc_dointvec_minmax,
325 		.strategy	= &sysctl_intvec,
326 		.extra2		= &tcp_retr1_max
327 	},
328 	{
329 		.ctl_name	= NET_IPV4_TCP_RETRIES2,
330 		.procname	= "tcp_retries2",
331 		.data		= &sysctl_tcp_retries2,
332 		.maxlen		= sizeof(int),
333 		.mode		= 0644,
334 		.proc_handler	= &proc_dointvec
335 	},
336 	{
337 		.ctl_name	= NET_IPV4_TCP_FIN_TIMEOUT,
338 		.procname	= "tcp_fin_timeout",
339 		.data		= &sysctl_tcp_fin_timeout,
340 		.maxlen		= sizeof(int),
341 		.mode		= 0644,
342 		.proc_handler	= &proc_dointvec_jiffies,
343 		.strategy	= &sysctl_jiffies
344 	},
345 #ifdef CONFIG_SYN_COOKIES
346 	{
347 		.ctl_name	= NET_TCP_SYNCOOKIES,
348 		.procname	= "tcp_syncookies",
349 		.data		= &sysctl_tcp_syncookies,
350 		.maxlen		= sizeof(int),
351 		.mode		= 0644,
352 		.proc_handler	= &proc_dointvec
353 	},
354 #endif
355 	{
356 		.ctl_name	= NET_TCP_TW_RECYCLE,
357 		.procname	= "tcp_tw_recycle",
358 		.data		= &tcp_death_row.sysctl_tw_recycle,
359 		.maxlen		= sizeof(int),
360 		.mode		= 0644,
361 		.proc_handler	= &proc_dointvec
362 	},
363 	{
364 		.ctl_name	= NET_TCP_ABORT_ON_OVERFLOW,
365 		.procname	= "tcp_abort_on_overflow",
366 		.data		= &sysctl_tcp_abort_on_overflow,
367 		.maxlen		= sizeof(int),
368 		.mode		= 0644,
369 		.proc_handler	= &proc_dointvec
370 	},
371 	{
372 		.ctl_name	= NET_TCP_STDURG,
373 		.procname	= "tcp_stdurg",
374 		.data		= &sysctl_tcp_stdurg,
375 		.maxlen		= sizeof(int),
376 		.mode		= 0644,
377 		.proc_handler	= &proc_dointvec
378 	},
379 	{
380 		.ctl_name	= NET_TCP_RFC1337,
381 		.procname	= "tcp_rfc1337",
382 		.data		= &sysctl_tcp_rfc1337,
383 		.maxlen		= sizeof(int),
384 		.mode		= 0644,
385 		.proc_handler	= &proc_dointvec
386 	},
387 	{
388 		.ctl_name	= NET_TCP_MAX_SYN_BACKLOG,
389 		.procname	= "tcp_max_syn_backlog",
390 		.data		= &sysctl_max_syn_backlog,
391 		.maxlen		= sizeof(int),
392 		.mode		= 0644,
393 		.proc_handler	= &proc_dointvec
394 	},
395 	{
396 		.ctl_name	= NET_IPV4_LOCAL_PORT_RANGE,
397 		.procname	= "ip_local_port_range",
398 		.data		= &sysctl_local_port_range,
399 		.maxlen		= sizeof(sysctl_local_port_range),
400 		.mode		= 0644,
401 		.proc_handler	= &ipv4_local_port_range,
402 		.strategy	= &ipv4_sysctl_local_port_range,
403 	},
404 	{
405 		.ctl_name	= NET_IPV4_ROUTE,
406 		.procname	= "route",
407 		.maxlen		= 0,
408 		.mode		= 0555,
409 		.child		= ipv4_route_table
410 	},
411 #ifdef CONFIG_IP_MULTICAST
412 	{
413 		.ctl_name	= NET_IPV4_IGMP_MAX_MEMBERSHIPS,
414 		.procname	= "igmp_max_memberships",
415 		.data		= &sysctl_igmp_max_memberships,
416 		.maxlen		= sizeof(int),
417 		.mode		= 0644,
418 		.proc_handler	= &proc_dointvec
419 	},
420 
421 #endif
422 	{
423 		.ctl_name	= NET_IPV4_IGMP_MAX_MSF,
424 		.procname	= "igmp_max_msf",
425 		.data		= &sysctl_igmp_max_msf,
426 		.maxlen		= sizeof(int),
427 		.mode		= 0644,
428 		.proc_handler	= &proc_dointvec
429 	},
430 	{
431 		.ctl_name	= NET_IPV4_INET_PEER_THRESHOLD,
432 		.procname	= "inet_peer_threshold",
433 		.data		= &inet_peer_threshold,
434 		.maxlen		= sizeof(int),
435 		.mode		= 0644,
436 		.proc_handler	= &proc_dointvec
437 	},
438 	{
439 		.ctl_name	= NET_IPV4_INET_PEER_MINTTL,
440 		.procname	= "inet_peer_minttl",
441 		.data		= &inet_peer_minttl,
442 		.maxlen		= sizeof(int),
443 		.mode		= 0644,
444 		.proc_handler	= &proc_dointvec_jiffies,
445 		.strategy	= &sysctl_jiffies
446 	},
447 	{
448 		.ctl_name	= NET_IPV4_INET_PEER_MAXTTL,
449 		.procname	= "inet_peer_maxttl",
450 		.data		= &inet_peer_maxttl,
451 		.maxlen		= sizeof(int),
452 		.mode		= 0644,
453 		.proc_handler	= &proc_dointvec_jiffies,
454 		.strategy	= &sysctl_jiffies
455 	},
456 	{
457 		.ctl_name	= NET_IPV4_INET_PEER_GC_MINTIME,
458 		.procname	= "inet_peer_gc_mintime",
459 		.data		= &inet_peer_gc_mintime,
460 		.maxlen		= sizeof(int),
461 		.mode		= 0644,
462 		.proc_handler	= &proc_dointvec_jiffies,
463 		.strategy	= &sysctl_jiffies
464 	},
465 	{
466 		.ctl_name	= NET_IPV4_INET_PEER_GC_MAXTIME,
467 		.procname	= "inet_peer_gc_maxtime",
468 		.data		= &inet_peer_gc_maxtime,
469 		.maxlen		= sizeof(int),
470 		.mode		= 0644,
471 		.proc_handler	= &proc_dointvec_jiffies,
472 		.strategy	= &sysctl_jiffies
473 	},
474 	{
475 		.ctl_name	= NET_TCP_ORPHAN_RETRIES,
476 		.procname	= "tcp_orphan_retries",
477 		.data		= &sysctl_tcp_orphan_retries,
478 		.maxlen		= sizeof(int),
479 		.mode		= 0644,
480 		.proc_handler	= &proc_dointvec
481 	},
482 	{
483 		.ctl_name	= NET_TCP_FACK,
484 		.procname	= "tcp_fack",
485 		.data		= &sysctl_tcp_fack,
486 		.maxlen		= sizeof(int),
487 		.mode		= 0644,
488 		.proc_handler	= &proc_dointvec
489 	},
490 	{
491 		.ctl_name	= NET_TCP_REORDERING,
492 		.procname	= "tcp_reordering",
493 		.data		= &sysctl_tcp_reordering,
494 		.maxlen		= sizeof(int),
495 		.mode		= 0644,
496 		.proc_handler	= &proc_dointvec
497 	},
498 	{
499 		.ctl_name	= NET_TCP_ECN,
500 		.procname	= "tcp_ecn",
501 		.data		= &sysctl_tcp_ecn,
502 		.maxlen		= sizeof(int),
503 		.mode		= 0644,
504 		.proc_handler	= &proc_dointvec
505 	},
506 	{
507 		.ctl_name	= NET_TCP_DSACK,
508 		.procname	= "tcp_dsack",
509 		.data		= &sysctl_tcp_dsack,
510 		.maxlen		= sizeof(int),
511 		.mode		= 0644,
512 		.proc_handler	= &proc_dointvec
513 	},
514 	{
515 		.ctl_name	= NET_TCP_MEM,
516 		.procname	= "tcp_mem",
517 		.data		= &sysctl_tcp_mem,
518 		.maxlen		= sizeof(sysctl_tcp_mem),
519 		.mode		= 0644,
520 		.proc_handler	= &proc_dointvec
521 	},
522 	{
523 		.ctl_name	= NET_TCP_WMEM,
524 		.procname	= "tcp_wmem",
525 		.data		= &sysctl_tcp_wmem,
526 		.maxlen		= sizeof(sysctl_tcp_wmem),
527 		.mode		= 0644,
528 		.proc_handler	= &proc_dointvec
529 	},
530 	{
531 		.ctl_name	= NET_TCP_RMEM,
532 		.procname	= "tcp_rmem",
533 		.data		= &sysctl_tcp_rmem,
534 		.maxlen		= sizeof(sysctl_tcp_rmem),
535 		.mode		= 0644,
536 		.proc_handler	= &proc_dointvec
537 	},
538 	{
539 		.ctl_name	= NET_TCP_APP_WIN,
540 		.procname	= "tcp_app_win",
541 		.data		= &sysctl_tcp_app_win,
542 		.maxlen		= sizeof(int),
543 		.mode		= 0644,
544 		.proc_handler	= &proc_dointvec
545 	},
546 	{
547 		.ctl_name	= NET_TCP_ADV_WIN_SCALE,
548 		.procname	= "tcp_adv_win_scale",
549 		.data		= &sysctl_tcp_adv_win_scale,
550 		.maxlen		= sizeof(int),
551 		.mode		= 0644,
552 		.proc_handler	= &proc_dointvec
553 	},
554 	{
555 		.ctl_name	= NET_TCP_TW_REUSE,
556 		.procname	= "tcp_tw_reuse",
557 		.data		= &sysctl_tcp_tw_reuse,
558 		.maxlen		= sizeof(int),
559 		.mode		= 0644,
560 		.proc_handler	= &proc_dointvec
561 	},
562 	{
563 		.ctl_name	= NET_TCP_FRTO,
564 		.procname	= "tcp_frto",
565 		.data		= &sysctl_tcp_frto,
566 		.maxlen		= sizeof(int),
567 		.mode		= 0644,
568 		.proc_handler	= &proc_dointvec
569 	},
570 	{
571 		.ctl_name	= NET_TCP_FRTO_RESPONSE,
572 		.procname	= "tcp_frto_response",
573 		.data		= &sysctl_tcp_frto_response,
574 		.maxlen		= sizeof(int),
575 		.mode		= 0644,
576 		.proc_handler	= &proc_dointvec
577 	},
578 	{
579 		.ctl_name	= NET_TCP_LOW_LATENCY,
580 		.procname	= "tcp_low_latency",
581 		.data		= &sysctl_tcp_low_latency,
582 		.maxlen		= sizeof(int),
583 		.mode		= 0644,
584 		.proc_handler	= &proc_dointvec
585 	},
586 	{
587 		.ctl_name	= NET_TCP_NO_METRICS_SAVE,
588 		.procname	= "tcp_no_metrics_save",
589 		.data		= &sysctl_tcp_nometrics_save,
590 		.maxlen		= sizeof(int),
591 		.mode		= 0644,
592 		.proc_handler	= &proc_dointvec,
593 	},
594 	{
595 		.ctl_name	= NET_TCP_MODERATE_RCVBUF,
596 		.procname	= "tcp_moderate_rcvbuf",
597 		.data		= &sysctl_tcp_moderate_rcvbuf,
598 		.maxlen		= sizeof(int),
599 		.mode		= 0644,
600 		.proc_handler	= &proc_dointvec,
601 	},
602 	{
603 		.ctl_name	= NET_TCP_TSO_WIN_DIVISOR,
604 		.procname	= "tcp_tso_win_divisor",
605 		.data		= &sysctl_tcp_tso_win_divisor,
606 		.maxlen		= sizeof(int),
607 		.mode		= 0644,
608 		.proc_handler	= &proc_dointvec,
609 	},
610 	{
611 		.ctl_name	= NET_TCP_CONG_CONTROL,
612 		.procname	= "tcp_congestion_control",
613 		.mode		= 0644,
614 		.maxlen		= TCP_CA_NAME_MAX,
615 		.proc_handler	= &proc_tcp_congestion_control,
616 		.strategy	= &sysctl_tcp_congestion_control,
617 	},
618 	{
619 		.ctl_name	= NET_TCP_ABC,
620 		.procname	= "tcp_abc",
621 		.data		= &sysctl_tcp_abc,
622 		.maxlen		= sizeof(int),
623 		.mode		= 0644,
624 		.proc_handler	= &proc_dointvec,
625 	},
626 	{
627 		.ctl_name	= NET_TCP_MTU_PROBING,
628 		.procname	= "tcp_mtu_probing",
629 		.data		= &sysctl_tcp_mtu_probing,
630 		.maxlen		= sizeof(int),
631 		.mode		= 0644,
632 		.proc_handler	= &proc_dointvec,
633 	},
634 	{
635 		.ctl_name	= NET_TCP_BASE_MSS,
636 		.procname	= "tcp_base_mss",
637 		.data		= &sysctl_tcp_base_mss,
638 		.maxlen		= sizeof(int),
639 		.mode		= 0644,
640 		.proc_handler	= &proc_dointvec,
641 	},
642 	{
643 		.ctl_name	= NET_IPV4_TCP_WORKAROUND_SIGNED_WINDOWS,
644 		.procname	= "tcp_workaround_signed_windows",
645 		.data		= &sysctl_tcp_workaround_signed_windows,
646 		.maxlen		= sizeof(int),
647 		.mode		= 0644,
648 		.proc_handler	= &proc_dointvec
649 	},
650 #ifdef CONFIG_NET_DMA
651 	{
652 		.ctl_name	= NET_TCP_DMA_COPYBREAK,
653 		.procname	= "tcp_dma_copybreak",
654 		.data		= &sysctl_tcp_dma_copybreak,
655 		.maxlen		= sizeof(int),
656 		.mode		= 0644,
657 		.proc_handler	= &proc_dointvec
658 	},
659 #endif
660 	{
661 		.ctl_name	= NET_TCP_SLOW_START_AFTER_IDLE,
662 		.procname	= "tcp_slow_start_after_idle",
663 		.data		= &sysctl_tcp_slow_start_after_idle,
664 		.maxlen		= sizeof(int),
665 		.mode		= 0644,
666 		.proc_handler	= &proc_dointvec
667 	},
668 #ifdef CONFIG_NETLABEL
669 	{
670 		.ctl_name	= NET_CIPSOV4_CACHE_ENABLE,
671 		.procname	= "cipso_cache_enable",
672 		.data		= &cipso_v4_cache_enabled,
673 		.maxlen		= sizeof(int),
674 		.mode		= 0644,
675 		.proc_handler	= &proc_dointvec,
676 	},
677 	{
678 		.ctl_name	= NET_CIPSOV4_CACHE_BUCKET_SIZE,
679 		.procname	= "cipso_cache_bucket_size",
680 		.data		= &cipso_v4_cache_bucketsize,
681 		.maxlen		= sizeof(int),
682 		.mode		= 0644,
683 		.proc_handler	= &proc_dointvec,
684 	},
685 	{
686 		.ctl_name	= NET_CIPSOV4_RBM_OPTFMT,
687 		.procname	= "cipso_rbm_optfmt",
688 		.data		= &cipso_v4_rbm_optfmt,
689 		.maxlen		= sizeof(int),
690 		.mode		= 0644,
691 		.proc_handler	= &proc_dointvec,
692 	},
693 	{
694 		.ctl_name	= NET_CIPSOV4_RBM_STRICTVALID,
695 		.procname	= "cipso_rbm_strictvalid",
696 		.data		= &cipso_v4_rbm_strictvalid,
697 		.maxlen		= sizeof(int),
698 		.mode		= 0644,
699 		.proc_handler	= &proc_dointvec,
700 	},
701 #endif /* CONFIG_NETLABEL */
702 	{
703 		.procname	= "tcp_available_congestion_control",
704 		.maxlen		= TCP_CA_BUF_MAX,
705 		.mode		= 0444,
706 		.proc_handler   = &proc_tcp_available_congestion_control,
707 	},
708 	{
709 		.ctl_name	= NET_TCP_ALLOWED_CONG_CONTROL,
710 		.procname	= "tcp_allowed_congestion_control",
711 		.maxlen		= TCP_CA_BUF_MAX,
712 		.mode		= 0644,
713 		.proc_handler   = &proc_allowed_congestion_control,
714 		.strategy	= &strategy_allowed_congestion_control,
715 	},
716 	{
717 		.ctl_name	= NET_TCP_MAX_SSTHRESH,
718 		.procname	= "tcp_max_ssthresh",
719 		.data		= &sysctl_tcp_max_ssthresh,
720 		.maxlen		= sizeof(int),
721 		.mode		= 0644,
722 		.proc_handler	= &proc_dointvec,
723 	},
724 	{
725 		.ctl_name	= CTL_UNNUMBERED,
726 		.procname	= "udp_mem",
727 		.data		= &sysctl_udp_mem,
728 		.maxlen		= sizeof(sysctl_udp_mem),
729 		.mode		= 0644,
730 		.proc_handler	= &proc_dointvec_minmax,
731 		.strategy	= &sysctl_intvec,
732 		.extra1		= &zero
733 	},
734 	{
735 		.ctl_name	= CTL_UNNUMBERED,
736 		.procname	= "udp_rmem_min",
737 		.data		= &sysctl_udp_rmem_min,
738 		.maxlen		= sizeof(sysctl_udp_rmem_min),
739 		.mode		= 0644,
740 		.proc_handler	= &proc_dointvec_minmax,
741 		.strategy	= &sysctl_intvec,
742 		.extra1		= &zero
743 	},
744 	{
745 		.ctl_name	= CTL_UNNUMBERED,
746 		.procname	= "udp_wmem_min",
747 		.data		= &sysctl_udp_wmem_min,
748 		.maxlen		= sizeof(sysctl_udp_wmem_min),
749 		.mode		= 0644,
750 		.proc_handler	= &proc_dointvec_minmax,
751 		.strategy	= &sysctl_intvec,
752 		.extra1		= &zero
753 	},
754 	{ .ctl_name = 0 }
755 };
756 
757 static struct ctl_table ipv4_net_table[] = {
758 	{
759 		.ctl_name	= NET_IPV4_ICMP_ECHO_IGNORE_ALL,
760 		.procname	= "icmp_echo_ignore_all",
761 		.data		= &init_net.ipv4.sysctl_icmp_echo_ignore_all,
762 		.maxlen		= sizeof(int),
763 		.mode		= 0644,
764 		.proc_handler	= &proc_dointvec
765 	},
766 	{
767 		.ctl_name	= NET_IPV4_ICMP_ECHO_IGNORE_BROADCASTS,
768 		.procname	= "icmp_echo_ignore_broadcasts",
769 		.data		= &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
770 		.maxlen		= sizeof(int),
771 		.mode		= 0644,
772 		.proc_handler	= &proc_dointvec
773 	},
774 	{
775 		.ctl_name	= NET_IPV4_ICMP_IGNORE_BOGUS_ERROR_RESPONSES,
776 		.procname	= "icmp_ignore_bogus_error_responses",
777 		.data		= &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
778 		.maxlen		= sizeof(int),
779 		.mode		= 0644,
780 		.proc_handler	= &proc_dointvec
781 	},
782 	{
783 		.ctl_name	= NET_IPV4_ICMP_ERRORS_USE_INBOUND_IFADDR,
784 		.procname	= "icmp_errors_use_inbound_ifaddr",
785 		.data		= &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
786 		.maxlen		= sizeof(int),
787 		.mode		= 0644,
788 		.proc_handler	= &proc_dointvec
789 	},
790 	{
791 		.ctl_name	= NET_IPV4_ICMP_RATELIMIT,
792 		.procname	= "icmp_ratelimit",
793 		.data		= &init_net.ipv4.sysctl_icmp_ratelimit,
794 		.maxlen		= sizeof(int),
795 		.mode		= 0644,
796 		.proc_handler	= &proc_dointvec_ms_jiffies,
797 		.strategy	= &sysctl_ms_jiffies
798 	},
799 	{
800 		.ctl_name	= NET_IPV4_ICMP_RATEMASK,
801 		.procname	= "icmp_ratemask",
802 		.data		= &init_net.ipv4.sysctl_icmp_ratemask,
803 		.maxlen		= sizeof(int),
804 		.mode		= 0644,
805 		.proc_handler	= &proc_dointvec
806 	},
807 	{ }
808 };
809 
810 struct ctl_path net_ipv4_ctl_path[] = {
811 	{ .procname = "net", .ctl_name = CTL_NET, },
812 	{ .procname = "ipv4", .ctl_name = NET_IPV4, },
813 	{ },
814 };
815 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
816 
817 static __net_init int ipv4_sysctl_init_net(struct net *net)
818 {
819 	struct ctl_table *table;
820 
821 	table = ipv4_net_table;
822 	if (net != &init_net) {
823 		table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
824 		if (table == NULL)
825 			goto err_alloc;
826 
827 		table[0].data =
828 			&net->ipv4.sysctl_icmp_echo_ignore_all;
829 		table[1].data =
830 			&net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
831 		table[2].data =
832 			&net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
833 		table[3].data =
834 			&net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
835 		table[4].data =
836 			&net->ipv4.sysctl_icmp_ratelimit;
837 		table[5].data =
838 			&net->ipv4.sysctl_icmp_ratemask;
839 	}
840 
841 	net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
842 			net_ipv4_ctl_path, table);
843 	if (net->ipv4.ipv4_hdr == NULL)
844 		goto err_reg;
845 
846 	return 0;
847 
848 err_reg:
849 	if (net != &init_net)
850 		kfree(table);
851 err_alloc:
852 	return -ENOMEM;
853 }
854 
855 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
856 {
857 	struct ctl_table *table;
858 
859 	table = net->ipv4.ipv4_hdr->ctl_table_arg;
860 	unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
861 	kfree(table);
862 }
863 
864 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
865 	.init = ipv4_sysctl_init_net,
866 	.exit = ipv4_sysctl_exit_net,
867 };
868 
869 static __init int sysctl_ipv4_init(void)
870 {
871 	struct ctl_table_header *hdr;
872 
873 	hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
874 	if (hdr == NULL)
875 		return -ENOMEM;
876 
877 	if (register_pernet_subsys(&ipv4_sysctl_ops)) {
878 		unregister_sysctl_table(hdr);
879 		return -ENOMEM;
880 	}
881 
882 	return 0;
883 }
884 
885 __initcall(sysctl_ipv4_init);
886