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