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 /* The following index defines are used in sctp_sysctl_net_register().
88 * If you add new items to the sctp_net_table, please ensure that
89 * the index values of these defines hold the same meaning indicated by
90 * their macro names when they appear in sctp_net_table.
91 */
92 #define SCTP_RTO_MIN_IDX 0
93 #define SCTP_RTO_MAX_IDX 1
94 #define SCTP_PF_RETRANS_IDX 2
95 #define SCTP_PS_RETRANS_IDX 3
96
97 static struct ctl_table sctp_net_table[] = {
98 [SCTP_RTO_MIN_IDX] = {
99 .procname = "rto_min",
100 .data = &init_net.sctp.rto_min,
101 .maxlen = sizeof(unsigned int),
102 .mode = 0644,
103 .proc_handler = proc_sctp_do_rto_min,
104 .extra1 = SYSCTL_ONE,
105 .extra2 = &init_net.sctp.rto_max
106 },
107 [SCTP_RTO_MAX_IDX] = {
108 .procname = "rto_max",
109 .data = &init_net.sctp.rto_max,
110 .maxlen = sizeof(unsigned int),
111 .mode = 0644,
112 .proc_handler = proc_sctp_do_rto_max,
113 .extra1 = &init_net.sctp.rto_min,
114 .extra2 = &timer_max
115 },
116 [SCTP_PF_RETRANS_IDX] = {
117 .procname = "pf_retrans",
118 .data = &init_net.sctp.pf_retrans,
119 .maxlen = sizeof(int),
120 .mode = 0644,
121 .proc_handler = proc_dointvec_minmax,
122 .extra1 = SYSCTL_ZERO,
123 .extra2 = &init_net.sctp.ps_retrans,
124 },
125 [SCTP_PS_RETRANS_IDX] = {
126 .procname = "ps_retrans",
127 .data = &init_net.sctp.ps_retrans,
128 .maxlen = sizeof(int),
129 .mode = 0644,
130 .proc_handler = proc_dointvec_minmax,
131 .extra1 = &init_net.sctp.pf_retrans,
132 .extra2 = &ps_retrans_max,
133 },
134 {
135 .procname = "rto_initial",
136 .data = &init_net.sctp.rto_initial,
137 .maxlen = sizeof(unsigned int),
138 .mode = 0644,
139 .proc_handler = proc_dointvec_minmax,
140 .extra1 = SYSCTL_ONE,
141 .extra2 = &timer_max
142 },
143 {
144 .procname = "rto_alpha_exp_divisor",
145 .data = &init_net.sctp.rto_alpha,
146 .maxlen = sizeof(int),
147 .mode = 0644,
148 .proc_handler = proc_sctp_do_alpha_beta,
149 .extra1 = &rto_alpha_min,
150 .extra2 = &rto_alpha_max,
151 },
152 {
153 .procname = "rto_beta_exp_divisor",
154 .data = &init_net.sctp.rto_beta,
155 .maxlen = sizeof(int),
156 .mode = 0644,
157 .proc_handler = proc_sctp_do_alpha_beta,
158 .extra1 = &rto_beta_min,
159 .extra2 = &rto_beta_max,
160 },
161 {
162 .procname = "max_burst",
163 .data = &init_net.sctp.max_burst,
164 .maxlen = sizeof(int),
165 .mode = 0644,
166 .proc_handler = proc_dointvec_minmax,
167 .extra1 = SYSCTL_ZERO,
168 .extra2 = SYSCTL_INT_MAX,
169 },
170 {
171 .procname = "cookie_preserve_enable",
172 .data = &init_net.sctp.cookie_preserve_enable,
173 .maxlen = sizeof(int),
174 .mode = 0644,
175 .proc_handler = proc_dointvec,
176 },
177 {
178 .procname = "cookie_hmac_alg",
179 .data = &init_net.sctp.sctp_hmac_alg,
180 .maxlen = 8,
181 .mode = 0644,
182 .proc_handler = proc_sctp_do_hmac_alg,
183 },
184 {
185 .procname = "valid_cookie_life",
186 .data = &init_net.sctp.valid_cookie_life,
187 .maxlen = sizeof(unsigned int),
188 .mode = 0644,
189 .proc_handler = proc_dointvec_minmax,
190 .extra1 = SYSCTL_ONE,
191 .extra2 = &timer_max
192 },
193 {
194 .procname = "sack_timeout",
195 .data = &init_net.sctp.sack_timeout,
196 .maxlen = sizeof(int),
197 .mode = 0644,
198 .proc_handler = proc_dointvec_minmax,
199 .extra1 = &sack_timer_min,
200 .extra2 = &sack_timer_max,
201 },
202 {
203 .procname = "hb_interval",
204 .data = &init_net.sctp.hb_interval,
205 .maxlen = sizeof(unsigned int),
206 .mode = 0644,
207 .proc_handler = proc_dointvec_minmax,
208 .extra1 = SYSCTL_ONE,
209 .extra2 = &timer_max
210 },
211 {
212 .procname = "association_max_retrans",
213 .data = &init_net.sctp.max_retrans_association,
214 .maxlen = sizeof(int),
215 .mode = 0644,
216 .proc_handler = proc_dointvec_minmax,
217 .extra1 = SYSCTL_ONE,
218 .extra2 = SYSCTL_INT_MAX,
219 },
220 {
221 .procname = "path_max_retrans",
222 .data = &init_net.sctp.max_retrans_path,
223 .maxlen = sizeof(int),
224 .mode = 0644,
225 .proc_handler = proc_dointvec_minmax,
226 .extra1 = SYSCTL_ONE,
227 .extra2 = SYSCTL_INT_MAX,
228 },
229 {
230 .procname = "max_init_retransmits",
231 .data = &init_net.sctp.max_retrans_init,
232 .maxlen = sizeof(int),
233 .mode = 0644,
234 .proc_handler = proc_dointvec_minmax,
235 .extra1 = SYSCTL_ONE,
236 .extra2 = SYSCTL_INT_MAX,
237 },
238 {
239 .procname = "sndbuf_policy",
240 .data = &init_net.sctp.sndbuf_policy,
241 .maxlen = sizeof(int),
242 .mode = 0644,
243 .proc_handler = proc_dointvec,
244 },
245 {
246 .procname = "rcvbuf_policy",
247 .data = &init_net.sctp.rcvbuf_policy,
248 .maxlen = sizeof(int),
249 .mode = 0644,
250 .proc_handler = proc_dointvec,
251 },
252 {
253 .procname = "default_auto_asconf",
254 .data = &init_net.sctp.default_auto_asconf,
255 .maxlen = sizeof(int),
256 .mode = 0644,
257 .proc_handler = proc_dointvec,
258 },
259 {
260 .procname = "addip_enable",
261 .data = &init_net.sctp.addip_enable,
262 .maxlen = sizeof(int),
263 .mode = 0644,
264 .proc_handler = proc_dointvec,
265 },
266 {
267 .procname = "addip_noauth_enable",
268 .data = &init_net.sctp.addip_noauth,
269 .maxlen = sizeof(int),
270 .mode = 0644,
271 .proc_handler = proc_dointvec,
272 },
273 {
274 .procname = "prsctp_enable",
275 .data = &init_net.sctp.prsctp_enable,
276 .maxlen = sizeof(int),
277 .mode = 0644,
278 .proc_handler = proc_dointvec,
279 },
280 {
281 .procname = "reconf_enable",
282 .data = &init_net.sctp.reconf_enable,
283 .maxlen = sizeof(int),
284 .mode = 0644,
285 .proc_handler = proc_dointvec,
286 },
287 {
288 .procname = "auth_enable",
289 .data = &init_net.sctp.auth_enable,
290 .maxlen = sizeof(int),
291 .mode = 0644,
292 .proc_handler = proc_sctp_do_auth,
293 },
294 {
295 .procname = "intl_enable",
296 .data = &init_net.sctp.intl_enable,
297 .maxlen = sizeof(int),
298 .mode = 0644,
299 .proc_handler = proc_dointvec,
300 },
301 {
302 .procname = "ecn_enable",
303 .data = &init_net.sctp.ecn_enable,
304 .maxlen = sizeof(int),
305 .mode = 0644,
306 .proc_handler = proc_dointvec,
307 },
308 {
309 .procname = "plpmtud_probe_interval",
310 .data = &init_net.sctp.probe_interval,
311 .maxlen = sizeof(int),
312 .mode = 0644,
313 .proc_handler = proc_sctp_do_probe_interval,
314 },
315 {
316 .procname = "udp_port",
317 .data = &init_net.sctp.udp_port,
318 .maxlen = sizeof(int),
319 .mode = 0644,
320 .proc_handler = proc_sctp_do_udp_port,
321 .extra1 = SYSCTL_ZERO,
322 .extra2 = &udp_port_max,
323 },
324 {
325 .procname = "encap_port",
326 .data = &init_net.sctp.encap_port,
327 .maxlen = sizeof(int),
328 .mode = 0644,
329 .proc_handler = proc_dointvec_minmax,
330 .extra1 = SYSCTL_ZERO,
331 .extra2 = &udp_port_max,
332 },
333 {
334 .procname = "addr_scope_policy",
335 .data = &init_net.sctp.scope_policy,
336 .maxlen = sizeof(int),
337 .mode = 0644,
338 .proc_handler = proc_dointvec_minmax,
339 .extra1 = SYSCTL_ZERO,
340 .extra2 = &addr_scope_max,
341 },
342 {
343 .procname = "rwnd_update_shift",
344 .data = &init_net.sctp.rwnd_upd_shift,
345 .maxlen = sizeof(int),
346 .mode = 0644,
347 .proc_handler = &proc_dointvec_minmax,
348 .extra1 = SYSCTL_ONE,
349 .extra2 = &rwnd_scale_max,
350 },
351 {
352 .procname = "max_autoclose",
353 .data = &init_net.sctp.max_autoclose,
354 .maxlen = sizeof(unsigned long),
355 .mode = 0644,
356 .proc_handler = &proc_doulongvec_minmax,
357 .extra1 = &max_autoclose_min,
358 .extra2 = &max_autoclose_max,
359 },
360 #ifdef CONFIG_NET_L3_MASTER_DEV
361 {
362 .procname = "l3mdev_accept",
363 .data = &init_net.sctp.l3mdev_accept,
364 .maxlen = sizeof(int),
365 .mode = 0644,
366 .proc_handler = proc_dointvec_minmax,
367 .extra1 = SYSCTL_ZERO,
368 .extra2 = SYSCTL_ONE,
369 },
370 #endif
371 {
372 .procname = "pf_enable",
373 .data = &init_net.sctp.pf_enable,
374 .maxlen = sizeof(int),
375 .mode = 0644,
376 .proc_handler = proc_dointvec,
377 },
378 {
379 .procname = "pf_expose",
380 .data = &init_net.sctp.pf_expose,
381 .maxlen = sizeof(int),
382 .mode = 0644,
383 .proc_handler = proc_dointvec_minmax,
384 .extra1 = SYSCTL_ZERO,
385 .extra2 = &pf_expose_max,
386 },
387
388 { /* sentinel */ }
389 };
390
proc_sctp_do_hmac_alg(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)391 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
392 void *buffer, size_t *lenp, loff_t *ppos)
393 {
394 struct net *net = current->nsproxy->net_ns;
395 struct ctl_table tbl;
396 bool changed = false;
397 char *none = "none";
398 char tmp[8] = {0};
399 int ret;
400
401 memset(&tbl, 0, sizeof(struct ctl_table));
402
403 if (write) {
404 tbl.data = tmp;
405 tbl.maxlen = sizeof(tmp);
406 } else {
407 tbl.data = net->sctp.sctp_hmac_alg ? : none;
408 tbl.maxlen = strlen(tbl.data);
409 }
410
411 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
412 if (write && ret == 0) {
413 #ifdef CONFIG_CRYPTO_MD5
414 if (!strncmp(tmp, "md5", 3)) {
415 net->sctp.sctp_hmac_alg = "md5";
416 changed = true;
417 }
418 #endif
419 #ifdef CONFIG_CRYPTO_SHA1
420 if (!strncmp(tmp, "sha1", 4)) {
421 net->sctp.sctp_hmac_alg = "sha1";
422 changed = true;
423 }
424 #endif
425 if (!strncmp(tmp, "none", 4)) {
426 net->sctp.sctp_hmac_alg = NULL;
427 changed = true;
428 }
429 if (!changed)
430 ret = -EINVAL;
431 }
432
433 return ret;
434 }
435
proc_sctp_do_rto_min(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)436 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
437 void *buffer, size_t *lenp, loff_t *ppos)
438 {
439 struct net *net = current->nsproxy->net_ns;
440 unsigned int min = *(unsigned int *) ctl->extra1;
441 unsigned int max = *(unsigned int *) ctl->extra2;
442 struct ctl_table tbl;
443 int ret, new_value;
444
445 memset(&tbl, 0, sizeof(struct ctl_table));
446 tbl.maxlen = sizeof(unsigned int);
447
448 if (write)
449 tbl.data = &new_value;
450 else
451 tbl.data = &net->sctp.rto_min;
452
453 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
454 if (write && ret == 0) {
455 if (new_value > max || new_value < min)
456 return -EINVAL;
457
458 net->sctp.rto_min = new_value;
459 }
460
461 return ret;
462 }
463
proc_sctp_do_rto_max(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)464 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
465 void *buffer, size_t *lenp, loff_t *ppos)
466 {
467 struct net *net = current->nsproxy->net_ns;
468 unsigned int min = *(unsigned int *) ctl->extra1;
469 unsigned int max = *(unsigned int *) ctl->extra2;
470 struct ctl_table tbl;
471 int ret, new_value;
472
473 memset(&tbl, 0, sizeof(struct ctl_table));
474 tbl.maxlen = sizeof(unsigned int);
475
476 if (write)
477 tbl.data = &new_value;
478 else
479 tbl.data = &net->sctp.rto_max;
480
481 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
482 if (write && ret == 0) {
483 if (new_value > max || new_value < min)
484 return -EINVAL;
485
486 net->sctp.rto_max = new_value;
487 }
488
489 return ret;
490 }
491
proc_sctp_do_alpha_beta(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)492 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
493 void *buffer, size_t *lenp, loff_t *ppos)
494 {
495 if (write)
496 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
497 "suboptimal rtt/srtt estimations!\n");
498
499 return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
500 }
501
proc_sctp_do_auth(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)502 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
503 void *buffer, size_t *lenp, loff_t *ppos)
504 {
505 struct net *net = current->nsproxy->net_ns;
506 struct ctl_table tbl;
507 int new_value, ret;
508
509 memset(&tbl, 0, sizeof(struct ctl_table));
510 tbl.maxlen = sizeof(unsigned int);
511
512 if (write)
513 tbl.data = &new_value;
514 else
515 tbl.data = &net->sctp.auth_enable;
516
517 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
518 if (write && ret == 0) {
519 struct sock *sk = net->sctp.ctl_sock;
520
521 net->sctp.auth_enable = new_value;
522 /* Update the value in the control socket */
523 lock_sock(sk);
524 sctp_sk(sk)->ep->auth_enable = new_value;
525 release_sock(sk);
526 }
527
528 return ret;
529 }
530
proc_sctp_do_udp_port(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)531 static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write,
532 void *buffer, size_t *lenp, loff_t *ppos)
533 {
534 struct net *net = current->nsproxy->net_ns;
535 unsigned int min = *(unsigned int *)ctl->extra1;
536 unsigned int max = *(unsigned int *)ctl->extra2;
537 struct ctl_table tbl;
538 int ret, new_value;
539
540 memset(&tbl, 0, sizeof(struct ctl_table));
541 tbl.maxlen = sizeof(unsigned int);
542
543 if (write)
544 tbl.data = &new_value;
545 else
546 tbl.data = &net->sctp.udp_port;
547
548 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
549 if (write && ret == 0) {
550 struct sock *sk = net->sctp.ctl_sock;
551
552 if (new_value > max || new_value < min)
553 return -EINVAL;
554
555 net->sctp.udp_port = new_value;
556 sctp_udp_sock_stop(net);
557 if (new_value) {
558 ret = sctp_udp_sock_start(net);
559 if (ret)
560 net->sctp.udp_port = 0;
561 }
562
563 /* Update the value in the control socket */
564 lock_sock(sk);
565 sctp_sk(sk)->udp_port = htons(net->sctp.udp_port);
566 release_sock(sk);
567 }
568
569 return ret;
570 }
571
proc_sctp_do_probe_interval(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)572 static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write,
573 void *buffer, size_t *lenp, loff_t *ppos)
574 {
575 struct net *net = current->nsproxy->net_ns;
576 struct ctl_table tbl;
577 int ret, new_value;
578
579 memset(&tbl, 0, sizeof(struct ctl_table));
580 tbl.maxlen = sizeof(unsigned int);
581
582 if (write)
583 tbl.data = &new_value;
584 else
585 tbl.data = &net->sctp.probe_interval;
586
587 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
588 if (write && ret == 0) {
589 if (new_value && new_value < SCTP_PROBE_TIMER_MIN)
590 return -EINVAL;
591
592 net->sctp.probe_interval = new_value;
593 }
594
595 return ret;
596 }
597
sctp_sysctl_net_register(struct net * net)598 int sctp_sysctl_net_register(struct net *net)
599 {
600 struct ctl_table *table;
601 int i;
602
603 table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
604 if (!table)
605 return -ENOMEM;
606
607 for (i = 0; table[i].data; i++)
608 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
609
610 table[SCTP_RTO_MIN_IDX].extra2 = &net->sctp.rto_max;
611 table[SCTP_RTO_MAX_IDX].extra1 = &net->sctp.rto_min;
612 table[SCTP_PF_RETRANS_IDX].extra2 = &net->sctp.ps_retrans;
613 table[SCTP_PS_RETRANS_IDX].extra1 = &net->sctp.pf_retrans;
614
615 net->sctp.sysctl_header = register_net_sysctl_sz(net, "net/sctp",
616 table,
617 ARRAY_SIZE(sctp_net_table));
618 if (net->sctp.sysctl_header == NULL) {
619 kfree(table);
620 return -ENOMEM;
621 }
622 return 0;
623 }
624
sctp_sysctl_net_unregister(struct net * net)625 void sctp_sysctl_net_unregister(struct net *net)
626 {
627 struct ctl_table *table;
628
629 table = net->sctp.sysctl_header->ctl_table_arg;
630 unregister_net_sysctl_table(net->sctp.sysctl_header);
631 kfree(table);
632 }
633
634 static struct ctl_table_header *sctp_sysctl_header;
635
636 /* Sysctl registration. */
sctp_sysctl_register(void)637 void sctp_sysctl_register(void)
638 {
639 sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
640 }
641
642 /* Sysctl deregistration. */
sctp_sysctl_unregister(void)643 void sctp_sysctl_unregister(void)
644 {
645 unregister_net_sysctl_table(sctp_sysctl_header);
646 }
647