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
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(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)387 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
388 void *buffer, size_t *lenp, loff_t *ppos)
389 {
390 struct net *net = current->nsproxy->net_ns;
391 struct ctl_table tbl;
392 bool changed = false;
393 char *none = "none";
394 char tmp[8] = {0};
395 int ret;
396
397 memset(&tbl, 0, sizeof(struct ctl_table));
398
399 if (write) {
400 tbl.data = tmp;
401 tbl.maxlen = sizeof(tmp);
402 } else {
403 tbl.data = net->sctp.sctp_hmac_alg ? : none;
404 tbl.maxlen = strlen(tbl.data);
405 }
406
407 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
408 if (write && ret == 0) {
409 #ifdef CONFIG_CRYPTO_MD5
410 if (!strncmp(tmp, "md5", 3)) {
411 net->sctp.sctp_hmac_alg = "md5";
412 changed = true;
413 }
414 #endif
415 #ifdef CONFIG_CRYPTO_SHA1
416 if (!strncmp(tmp, "sha1", 4)) {
417 net->sctp.sctp_hmac_alg = "sha1";
418 changed = true;
419 }
420 #endif
421 if (!strncmp(tmp, "none", 4)) {
422 net->sctp.sctp_hmac_alg = NULL;
423 changed = true;
424 }
425 if (!changed)
426 ret = -EINVAL;
427 }
428
429 return ret;
430 }
431
proc_sctp_do_rto_min(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)432 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
433 void *buffer, size_t *lenp, loff_t *ppos)
434 {
435 struct net *net = current->nsproxy->net_ns;
436 unsigned int min = *(unsigned int *) ctl->extra1;
437 unsigned int max = *(unsigned int *) ctl->extra2;
438 struct ctl_table tbl;
439 int ret, new_value;
440
441 memset(&tbl, 0, sizeof(struct ctl_table));
442 tbl.maxlen = sizeof(unsigned int);
443
444 if (write)
445 tbl.data = &new_value;
446 else
447 tbl.data = &net->sctp.rto_min;
448
449 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
450 if (write && ret == 0) {
451 if (new_value > max || new_value < min)
452 return -EINVAL;
453
454 net->sctp.rto_min = new_value;
455 }
456
457 return ret;
458 }
459
proc_sctp_do_rto_max(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)460 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
461 void *buffer, size_t *lenp, loff_t *ppos)
462 {
463 struct net *net = current->nsproxy->net_ns;
464 unsigned int min = *(unsigned int *) ctl->extra1;
465 unsigned int max = *(unsigned int *) ctl->extra2;
466 struct ctl_table tbl;
467 int ret, new_value;
468
469 memset(&tbl, 0, sizeof(struct ctl_table));
470 tbl.maxlen = sizeof(unsigned int);
471
472 if (write)
473 tbl.data = &new_value;
474 else
475 tbl.data = &net->sctp.rto_max;
476
477 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
478 if (write && ret == 0) {
479 if (new_value > max || new_value < min)
480 return -EINVAL;
481
482 net->sctp.rto_max = new_value;
483 }
484
485 return ret;
486 }
487
proc_sctp_do_alpha_beta(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)488 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
489 void *buffer, size_t *lenp, loff_t *ppos)
490 {
491 if (write)
492 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
493 "suboptimal rtt/srtt estimations!\n");
494
495 return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
496 }
497
proc_sctp_do_auth(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)498 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
499 void *buffer, size_t *lenp, loff_t *ppos)
500 {
501 struct net *net = current->nsproxy->net_ns;
502 struct ctl_table tbl;
503 int new_value, ret;
504
505 memset(&tbl, 0, sizeof(struct ctl_table));
506 tbl.maxlen = sizeof(unsigned int);
507
508 if (write)
509 tbl.data = &new_value;
510 else
511 tbl.data = &net->sctp.auth_enable;
512
513 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
514 if (write && ret == 0) {
515 struct sock *sk = net->sctp.ctl_sock;
516
517 net->sctp.auth_enable = new_value;
518 /* Update the value in the control socket */
519 lock_sock(sk);
520 sctp_sk(sk)->ep->auth_enable = new_value;
521 release_sock(sk);
522 }
523
524 return ret;
525 }
526
proc_sctp_do_udp_port(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)527 static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write,
528 void *buffer, size_t *lenp, loff_t *ppos)
529 {
530 struct net *net = current->nsproxy->net_ns;
531 unsigned int min = *(unsigned int *)ctl->extra1;
532 unsigned int max = *(unsigned int *)ctl->extra2;
533 struct ctl_table tbl;
534 int ret, new_value;
535
536 memset(&tbl, 0, sizeof(struct ctl_table));
537 tbl.maxlen = sizeof(unsigned int);
538
539 if (write)
540 tbl.data = &new_value;
541 else
542 tbl.data = &net->sctp.udp_port;
543
544 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
545 if (write && ret == 0) {
546 struct sock *sk = net->sctp.ctl_sock;
547
548 if (new_value > max || new_value < min)
549 return -EINVAL;
550
551 net->sctp.udp_port = new_value;
552 sctp_udp_sock_stop(net);
553 if (new_value) {
554 ret = sctp_udp_sock_start(net);
555 if (ret)
556 net->sctp.udp_port = 0;
557 }
558
559 /* Update the value in the control socket */
560 lock_sock(sk);
561 sctp_sk(sk)->udp_port = htons(net->sctp.udp_port);
562 release_sock(sk);
563 }
564
565 return ret;
566 }
567
proc_sctp_do_probe_interval(struct ctl_table * ctl,int write,void * buffer,size_t * lenp,loff_t * ppos)568 static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write,
569 void *buffer, size_t *lenp, loff_t *ppos)
570 {
571 struct net *net = current->nsproxy->net_ns;
572 struct ctl_table tbl;
573 int ret, new_value;
574
575 memset(&tbl, 0, sizeof(struct ctl_table));
576 tbl.maxlen = sizeof(unsigned int);
577
578 if (write)
579 tbl.data = &new_value;
580 else
581 tbl.data = &net->sctp.probe_interval;
582
583 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
584 if (write && ret == 0) {
585 if (new_value && new_value < SCTP_PROBE_TIMER_MIN)
586 return -EINVAL;
587
588 net->sctp.probe_interval = new_value;
589 }
590
591 return ret;
592 }
593
sctp_sysctl_net_register(struct net * net)594 int sctp_sysctl_net_register(struct net *net)
595 {
596 size_t table_size = ARRAY_SIZE(sctp_net_table);
597 struct ctl_table *table;
598 int i;
599
600 table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
601 if (!table)
602 return -ENOMEM;
603
604 for (i = 0; i < table_size; i++)
605 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
606
607 table[SCTP_RTO_MIN_IDX].extra2 = &net->sctp.rto_max;
608 table[SCTP_RTO_MAX_IDX].extra1 = &net->sctp.rto_min;
609 table[SCTP_PF_RETRANS_IDX].extra2 = &net->sctp.ps_retrans;
610 table[SCTP_PS_RETRANS_IDX].extra1 = &net->sctp.pf_retrans;
611
612 net->sctp.sysctl_header = register_net_sysctl_sz(net, "net/sctp",
613 table, table_size);
614 if (net->sctp.sysctl_header == NULL) {
615 kfree(table);
616 return -ENOMEM;
617 }
618 return 0;
619 }
620
sctp_sysctl_net_unregister(struct net * net)621 void sctp_sysctl_net_unregister(struct net *net)
622 {
623 const struct ctl_table *table;
624
625 table = net->sctp.sysctl_header->ctl_table_arg;
626 unregister_net_sysctl_table(net->sctp.sysctl_header);
627 kfree(table);
628 }
629
630 static struct ctl_table_header *sctp_sysctl_header;
631
632 /* Sysctl registration. */
sctp_sysctl_register(void)633 void sctp_sysctl_register(void)
634 {
635 sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
636 }
637
638 /* Sysctl deregistration. */
sctp_sysctl_unregister(void)639 void sctp_sysctl_unregister(void)
640 {
641 unregister_net_sysctl_table(sctp_sysctl_header);
642 }
643