xref: /linux/net/sctp/sysctl.c (revision 2da68a77) 
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* SCTP kernel implementation
3  * (C) Copyright IBM Corp. 2002, 2004
4  * Copyright (c) 2002 Intel Corp.
5  *
6  * This file is part of the SCTP kernel implementation
7  *
8  * Sysctl related interfaces for SCTP.
9  *
10  * Please send any bug reports or fixes you make to the
11  * email address(es):
12  *    lksctp developers <linux-sctp@vger.kernel.org>
13  *
14  * Written or modified by:
15  *    Mingqin Liu           <liuming@us.ibm.com>
16  *    Jon Grimm             <jgrimm@us.ibm.com>
17  *    Ardelle Fan           <ardelle.fan@intel.com>
18  *    Ryan Layer            <rmlayer@us.ibm.com>
19  *    Sridhar Samudrala     <sri@us.ibm.com>
20  */
21 
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 
24 #include <net/sctp/structs.h>
25 #include <net/sctp/sctp.h>
26 #include <linux/sysctl.h>
27 
28 static int timer_max = 86400000; /* ms in one day */
29 static int sack_timer_min = 1;
30 static int sack_timer_max = 500;
31 static int addr_scope_max = SCTP_SCOPE_POLICY_MAX;
32 static int rwnd_scale_max = 16;
33 static int rto_alpha_min = 0;
34 static int rto_beta_min = 0;
35 static int rto_alpha_max = 1000;
36 static int rto_beta_max = 1000;
37 static int pf_expose_max = SCTP_PF_EXPOSE_MAX;
38 static int ps_retrans_max = SCTP_PS_RETRANS_MAX;
39 static int udp_port_max = 65535;
40 
41 static unsigned long max_autoclose_min = 0;
42 static unsigned long max_autoclose_max =
43 	(MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
44 	? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
45 
46 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
47 				 void *buffer, size_t *lenp, loff_t *ppos);
48 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
49 				void *buffer, size_t *lenp, loff_t *ppos);
50 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write, void *buffer,
51 				size_t *lenp, loff_t *ppos);
52 static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write, void *buffer,
53 				 size_t *lenp, loff_t *ppos);
54 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
55 				   void *buffer, size_t *lenp, loff_t *ppos);
56 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
57 			     void *buffer, size_t *lenp, loff_t *ppos);
58 static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write,
59 				       void *buffer, size_t *lenp, loff_t *ppos);
60 
61 static struct ctl_table sctp_table[] = {
62 	{
63 		.procname	= "sctp_mem",
64 		.data		= &sysctl_sctp_mem,
65 		.maxlen		= sizeof(sysctl_sctp_mem),
66 		.mode		= 0644,
67 		.proc_handler	= proc_doulongvec_minmax
68 	},
69 	{
70 		.procname	= "sctp_rmem",
71 		.data		= &sysctl_sctp_rmem,
72 		.maxlen		= sizeof(sysctl_sctp_rmem),
73 		.mode		= 0644,
74 		.proc_handler	= proc_dointvec,
75 	},
76 	{
77 		.procname	= "sctp_wmem",
78 		.data		= &sysctl_sctp_wmem,
79 		.maxlen		= sizeof(sysctl_sctp_wmem),
80 		.mode		= 0644,
81 		.proc_handler	= proc_dointvec,
82 	},
83 
84 	{ /* sentinel */ }
85 };
86 
87 static struct ctl_table sctp_net_table[] = {
88 	{
89 		.procname	= "rto_initial",
90 		.data		= &init_net.sctp.rto_initial,
91 		.maxlen		= sizeof(unsigned int),
92 		.mode		= 0644,
93 		.proc_handler	= proc_dointvec_minmax,
94 		.extra1         = SYSCTL_ONE,
95 		.extra2         = &timer_max
96 	},
97 	{
98 		.procname	= "rto_min",
99 		.data		= &init_net.sctp.rto_min,
100 		.maxlen		= sizeof(unsigned int),
101 		.mode		= 0644,
102 		.proc_handler	= proc_sctp_do_rto_min,
103 		.extra1         = SYSCTL_ONE,
104 		.extra2         = &init_net.sctp.rto_max
105 	},
106 	{
107 		.procname	= "rto_max",
108 		.data		= &init_net.sctp.rto_max,
109 		.maxlen		= sizeof(unsigned int),
110 		.mode		= 0644,
111 		.proc_handler	= proc_sctp_do_rto_max,
112 		.extra1         = &init_net.sctp.rto_min,
113 		.extra2         = &timer_max
114 	},
115 	{
116 		.procname	= "rto_alpha_exp_divisor",
117 		.data		= &init_net.sctp.rto_alpha,
118 		.maxlen		= sizeof(int),
119 		.mode		= 0644,
120 		.proc_handler	= proc_sctp_do_alpha_beta,
121 		.extra1		= &rto_alpha_min,
122 		.extra2		= &rto_alpha_max,
123 	},
124 	{
125 		.procname	= "rto_beta_exp_divisor",
126 		.data		= &init_net.sctp.rto_beta,
127 		.maxlen		= sizeof(int),
128 		.mode		= 0644,
129 		.proc_handler	= proc_sctp_do_alpha_beta,
130 		.extra1		= &rto_beta_min,
131 		.extra2		= &rto_beta_max,
132 	},
133 	{
134 		.procname	= "max_burst",
135 		.data		= &init_net.sctp.max_burst,
136 		.maxlen		= sizeof(int),
137 		.mode		= 0644,
138 		.proc_handler	= proc_dointvec_minmax,
139 		.extra1		= SYSCTL_ZERO,
140 		.extra2		= SYSCTL_INT_MAX,
141 	},
142 	{
143 		.procname	= "cookie_preserve_enable",
144 		.data		= &init_net.sctp.cookie_preserve_enable,
145 		.maxlen		= sizeof(int),
146 		.mode		= 0644,
147 		.proc_handler	= proc_dointvec,
148 	},
149 	{
150 		.procname	= "cookie_hmac_alg",
151 		.data		= &init_net.sctp.sctp_hmac_alg,
152 		.maxlen		= 8,
153 		.mode		= 0644,
154 		.proc_handler	= proc_sctp_do_hmac_alg,
155 	},
156 	{
157 		.procname	= "valid_cookie_life",
158 		.data		= &init_net.sctp.valid_cookie_life,
159 		.maxlen		= sizeof(unsigned int),
160 		.mode		= 0644,
161 		.proc_handler	= proc_dointvec_minmax,
162 		.extra1         = SYSCTL_ONE,
163 		.extra2         = &timer_max
164 	},
165 	{
166 		.procname	= "sack_timeout",
167 		.data		= &init_net.sctp.sack_timeout,
168 		.maxlen		= sizeof(int),
169 		.mode		= 0644,
170 		.proc_handler	= proc_dointvec_minmax,
171 		.extra1         = &sack_timer_min,
172 		.extra2         = &sack_timer_max,
173 	},
174 	{
175 		.procname	= "hb_interval",
176 		.data		= &init_net.sctp.hb_interval,
177 		.maxlen		= sizeof(unsigned int),
178 		.mode		= 0644,
179 		.proc_handler	= proc_dointvec_minmax,
180 		.extra1         = SYSCTL_ONE,
181 		.extra2         = &timer_max
182 	},
183 	{
184 		.procname	= "association_max_retrans",
185 		.data		= &init_net.sctp.max_retrans_association,
186 		.maxlen		= sizeof(int),
187 		.mode		= 0644,
188 		.proc_handler	= proc_dointvec_minmax,
189 		.extra1		= SYSCTL_ONE,
190 		.extra2		= SYSCTL_INT_MAX,
191 	},
192 	{
193 		.procname	= "path_max_retrans",
194 		.data		= &init_net.sctp.max_retrans_path,
195 		.maxlen		= sizeof(int),
196 		.mode		= 0644,
197 		.proc_handler	= proc_dointvec_minmax,
198 		.extra1		= SYSCTL_ONE,
199 		.extra2		= SYSCTL_INT_MAX,
200 	},
201 	{
202 		.procname	= "max_init_retransmits",
203 		.data		= &init_net.sctp.max_retrans_init,
204 		.maxlen		= sizeof(int),
205 		.mode		= 0644,
206 		.proc_handler	= proc_dointvec_minmax,
207 		.extra1		= SYSCTL_ONE,
208 		.extra2		= SYSCTL_INT_MAX,
209 	},
210 	{
211 		.procname	= "pf_retrans",
212 		.data		= &init_net.sctp.pf_retrans,
213 		.maxlen		= sizeof(int),
214 		.mode		= 0644,
215 		.proc_handler	= proc_dointvec_minmax,
216 		.extra1		= SYSCTL_ZERO,
217 		.extra2		= &init_net.sctp.ps_retrans,
218 	},
219 	{
220 		.procname	= "ps_retrans",
221 		.data		= &init_net.sctp.ps_retrans,
222 		.maxlen		= sizeof(int),
223 		.mode		= 0644,
224 		.proc_handler	= proc_dointvec_minmax,
225 		.extra1		= &init_net.sctp.pf_retrans,
226 		.extra2		= &ps_retrans_max,
227 	},
228 	{
229 		.procname	= "sndbuf_policy",
230 		.data		= &init_net.sctp.sndbuf_policy,
231 		.maxlen		= sizeof(int),
232 		.mode		= 0644,
233 		.proc_handler	= proc_dointvec,
234 	},
235 	{
236 		.procname	= "rcvbuf_policy",
237 		.data		= &init_net.sctp.rcvbuf_policy,
238 		.maxlen		= sizeof(int),
239 		.mode		= 0644,
240 		.proc_handler	= proc_dointvec,
241 	},
242 	{
243 		.procname	= "default_auto_asconf",
244 		.data		= &init_net.sctp.default_auto_asconf,
245 		.maxlen		= sizeof(int),
246 		.mode		= 0644,
247 		.proc_handler	= proc_dointvec,
248 	},
249 	{
250 		.procname	= "addip_enable",
251 		.data		= &init_net.sctp.addip_enable,
252 		.maxlen		= sizeof(int),
253 		.mode		= 0644,
254 		.proc_handler	= proc_dointvec,
255 	},
256 	{
257 		.procname	= "addip_noauth_enable",
258 		.data		= &init_net.sctp.addip_noauth,
259 		.maxlen		= sizeof(int),
260 		.mode		= 0644,
261 		.proc_handler	= proc_dointvec,
262 	},
263 	{
264 		.procname	= "prsctp_enable",
265 		.data		= &init_net.sctp.prsctp_enable,
266 		.maxlen		= sizeof(int),
267 		.mode		= 0644,
268 		.proc_handler	= proc_dointvec,
269 	},
270 	{
271 		.procname	= "reconf_enable",
272 		.data		= &init_net.sctp.reconf_enable,
273 		.maxlen		= sizeof(int),
274 		.mode		= 0644,
275 		.proc_handler	= proc_dointvec,
276 	},
277 	{
278 		.procname	= "auth_enable",
279 		.data		= &init_net.sctp.auth_enable,
280 		.maxlen		= sizeof(int),
281 		.mode		= 0644,
282 		.proc_handler	= proc_sctp_do_auth,
283 	},
284 	{
285 		.procname	= "intl_enable",
286 		.data		= &init_net.sctp.intl_enable,
287 		.maxlen		= sizeof(int),
288 		.mode		= 0644,
289 		.proc_handler	= proc_dointvec,
290 	},
291 	{
292 		.procname	= "ecn_enable",
293 		.data		= &init_net.sctp.ecn_enable,
294 		.maxlen		= sizeof(int),
295 		.mode		= 0644,
296 		.proc_handler	= proc_dointvec,
297 	},
298 	{
299 		.procname	= "plpmtud_probe_interval",
300 		.data		= &init_net.sctp.probe_interval,
301 		.maxlen		= sizeof(int),
302 		.mode		= 0644,
303 		.proc_handler	= proc_sctp_do_probe_interval,
304 	},
305 	{
306 		.procname	= "udp_port",
307 		.data		= &init_net.sctp.udp_port,
308 		.maxlen		= sizeof(int),
309 		.mode		= 0644,
310 		.proc_handler	= proc_sctp_do_udp_port,
311 		.extra1		= SYSCTL_ZERO,
312 		.extra2		= &udp_port_max,
313 	},
314 	{
315 		.procname	= "encap_port",
316 		.data		= &init_net.sctp.encap_port,
317 		.maxlen		= sizeof(int),
318 		.mode		= 0644,
319 		.proc_handler	= proc_dointvec_minmax,
320 		.extra1		= SYSCTL_ZERO,
321 		.extra2		= &udp_port_max,
322 	},
323 	{
324 		.procname	= "addr_scope_policy",
325 		.data		= &init_net.sctp.scope_policy,
326 		.maxlen		= sizeof(int),
327 		.mode		= 0644,
328 		.proc_handler	= proc_dointvec_minmax,
329 		.extra1		= SYSCTL_ZERO,
330 		.extra2		= &addr_scope_max,
331 	},
332 	{
333 		.procname	= "rwnd_update_shift",
334 		.data		= &init_net.sctp.rwnd_upd_shift,
335 		.maxlen		= sizeof(int),
336 		.mode		= 0644,
337 		.proc_handler	= &proc_dointvec_minmax,
338 		.extra1		= SYSCTL_ONE,
339 		.extra2		= &rwnd_scale_max,
340 	},
341 	{
342 		.procname	= "max_autoclose",
343 		.data		= &init_net.sctp.max_autoclose,
344 		.maxlen		= sizeof(unsigned long),
345 		.mode		= 0644,
346 		.proc_handler	= &proc_doulongvec_minmax,
347 		.extra1		= &max_autoclose_min,
348 		.extra2		= &max_autoclose_max,
349 	},
350 	{
351 		.procname	= "pf_enable",
352 		.data		= &init_net.sctp.pf_enable,
353 		.maxlen		= sizeof(int),
354 		.mode		= 0644,
355 		.proc_handler	= proc_dointvec,
356 	},
357 	{
358 		.procname	= "pf_expose",
359 		.data		= &init_net.sctp.pf_expose,
360 		.maxlen		= sizeof(int),
361 		.mode		= 0644,
362 		.proc_handler	= proc_dointvec_minmax,
363 		.extra1		= SYSCTL_ZERO,
364 		.extra2		= &pf_expose_max,
365 	},
366 
367 	{ /* sentinel */ }
368 };
369 
370 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
371 				 void *buffer, size_t *lenp, loff_t *ppos)
372 {
373 	struct net *net = current->nsproxy->net_ns;
374 	struct ctl_table tbl;
375 	bool changed = false;
376 	char *none = "none";
377 	char tmp[8] = {0};
378 	int ret;
379 
380 	memset(&tbl, 0, sizeof(struct ctl_table));
381 
382 	if (write) {
383 		tbl.data = tmp;
384 		tbl.maxlen = sizeof(tmp);
385 	} else {
386 		tbl.data = net->sctp.sctp_hmac_alg ? : none;
387 		tbl.maxlen = strlen(tbl.data);
388 	}
389 
390 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
391 	if (write && ret == 0) {
392 #ifdef CONFIG_CRYPTO_MD5
393 		if (!strncmp(tmp, "md5", 3)) {
394 			net->sctp.sctp_hmac_alg = "md5";
395 			changed = true;
396 		}
397 #endif
398 #ifdef CONFIG_CRYPTO_SHA1
399 		if (!strncmp(tmp, "sha1", 4)) {
400 			net->sctp.sctp_hmac_alg = "sha1";
401 			changed = true;
402 		}
403 #endif
404 		if (!strncmp(tmp, "none", 4)) {
405 			net->sctp.sctp_hmac_alg = NULL;
406 			changed = true;
407 		}
408 		if (!changed)
409 			ret = -EINVAL;
410 	}
411 
412 	return ret;
413 }
414 
415 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
416 				void *buffer, size_t *lenp, loff_t *ppos)
417 {
418 	struct net *net = current->nsproxy->net_ns;
419 	unsigned int min = *(unsigned int *) ctl->extra1;
420 	unsigned int max = *(unsigned int *) ctl->extra2;
421 	struct ctl_table tbl;
422 	int ret, new_value;
423 
424 	memset(&tbl, 0, sizeof(struct ctl_table));
425 	tbl.maxlen = sizeof(unsigned int);
426 
427 	if (write)
428 		tbl.data = &new_value;
429 	else
430 		tbl.data = &net->sctp.rto_min;
431 
432 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
433 	if (write && ret == 0) {
434 		if (new_value > max || new_value < min)
435 			return -EINVAL;
436 
437 		net->sctp.rto_min = new_value;
438 	}
439 
440 	return ret;
441 }
442 
443 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
444 				void *buffer, size_t *lenp, loff_t *ppos)
445 {
446 	struct net *net = current->nsproxy->net_ns;
447 	unsigned int min = *(unsigned int *) ctl->extra1;
448 	unsigned int max = *(unsigned int *) ctl->extra2;
449 	struct ctl_table tbl;
450 	int ret, new_value;
451 
452 	memset(&tbl, 0, sizeof(struct ctl_table));
453 	tbl.maxlen = sizeof(unsigned int);
454 
455 	if (write)
456 		tbl.data = &new_value;
457 	else
458 		tbl.data = &net->sctp.rto_max;
459 
460 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
461 	if (write && ret == 0) {
462 		if (new_value > max || new_value < min)
463 			return -EINVAL;
464 
465 		net->sctp.rto_max = new_value;
466 	}
467 
468 	return ret;
469 }
470 
471 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
472 				   void *buffer, size_t *lenp, loff_t *ppos)
473 {
474 	if (write)
475 		pr_warn_once("Changing rto_alpha or rto_beta may lead to "
476 			     "suboptimal rtt/srtt estimations!\n");
477 
478 	return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
479 }
480 
481 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
482 			     void *buffer, size_t *lenp, loff_t *ppos)
483 {
484 	struct net *net = current->nsproxy->net_ns;
485 	struct ctl_table tbl;
486 	int new_value, ret;
487 
488 	memset(&tbl, 0, sizeof(struct ctl_table));
489 	tbl.maxlen = sizeof(unsigned int);
490 
491 	if (write)
492 		tbl.data = &new_value;
493 	else
494 		tbl.data = &net->sctp.auth_enable;
495 
496 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
497 	if (write && ret == 0) {
498 		struct sock *sk = net->sctp.ctl_sock;
499 
500 		net->sctp.auth_enable = new_value;
501 		/* Update the value in the control socket */
502 		lock_sock(sk);
503 		sctp_sk(sk)->ep->auth_enable = new_value;
504 		release_sock(sk);
505 	}
506 
507 	return ret;
508 }
509 
510 static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write,
511 				 void *buffer, size_t *lenp, loff_t *ppos)
512 {
513 	struct net *net = current->nsproxy->net_ns;
514 	unsigned int min = *(unsigned int *)ctl->extra1;
515 	unsigned int max = *(unsigned int *)ctl->extra2;
516 	struct ctl_table tbl;
517 	int ret, new_value;
518 
519 	memset(&tbl, 0, sizeof(struct ctl_table));
520 	tbl.maxlen = sizeof(unsigned int);
521 
522 	if (write)
523 		tbl.data = &new_value;
524 	else
525 		tbl.data = &net->sctp.udp_port;
526 
527 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
528 	if (write && ret == 0) {
529 		struct sock *sk = net->sctp.ctl_sock;
530 
531 		if (new_value > max || new_value < min)
532 			return -EINVAL;
533 
534 		net->sctp.udp_port = new_value;
535 		sctp_udp_sock_stop(net);
536 		if (new_value) {
537 			ret = sctp_udp_sock_start(net);
538 			if (ret)
539 				net->sctp.udp_port = 0;
540 		}
541 
542 		/* Update the value in the control socket */
543 		lock_sock(sk);
544 		sctp_sk(sk)->udp_port = htons(net->sctp.udp_port);
545 		release_sock(sk);
546 	}
547 
548 	return ret;
549 }
550 
551 static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write,
552 				       void *buffer, size_t *lenp, loff_t *ppos)
553 {
554 	struct net *net = current->nsproxy->net_ns;
555 	struct ctl_table tbl;
556 	int ret, new_value;
557 
558 	memset(&tbl, 0, sizeof(struct ctl_table));
559 	tbl.maxlen = sizeof(unsigned int);
560 
561 	if (write)
562 		tbl.data = &new_value;
563 	else
564 		tbl.data = &net->sctp.probe_interval;
565 
566 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
567 	if (write && ret == 0) {
568 		if (new_value && new_value < SCTP_PROBE_TIMER_MIN)
569 			return -EINVAL;
570 
571 		net->sctp.probe_interval = new_value;
572 	}
573 
574 	return ret;
575 }
576 
577 int sctp_sysctl_net_register(struct net *net)
578 {
579 	struct ctl_table *table;
580 	int i;
581 
582 	table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
583 	if (!table)
584 		return -ENOMEM;
585 
586 	for (i = 0; table[i].data; i++)
587 		table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
588 
589 	net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
590 	if (net->sctp.sysctl_header == NULL) {
591 		kfree(table);
592 		return -ENOMEM;
593 	}
594 	return 0;
595 }
596 
597 void sctp_sysctl_net_unregister(struct net *net)
598 {
599 	struct ctl_table *table;
600 
601 	table = net->sctp.sysctl_header->ctl_table_arg;
602 	unregister_net_sysctl_table(net->sctp.sysctl_header);
603 	kfree(table);
604 }
605 
606 static struct ctl_table_header *sctp_sysctl_header;
607 
608 /* Sysctl registration.  */
609 void sctp_sysctl_register(void)
610 {
611 	sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
612 }
613 
614 /* Sysctl deregistration.  */
615 void sctp_sysctl_unregister(void)
616 {
617 	unregister_net_sysctl_table(sctp_sysctl_header);
618 }
619