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
38 static unsigned long max_autoclose_min = 0;
39 static unsigned long max_autoclose_max =
40 (MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
41 ? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
42
43 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
44 void __user *buffer, size_t *lenp,
45 loff_t *ppos);
46 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
47 void __user *buffer, size_t *lenp,
48 loff_t *ppos);
49 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
50 void __user *buffer, size_t *lenp,
51 loff_t *ppos);
52 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
53 void __user *buffer, size_t *lenp,
54 loff_t *ppos);
55 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
56 void __user *buffer, size_t *lenp,
57 loff_t *ppos);
58
59 static struct ctl_table sctp_table[] = {
60 {
61 .procname = "sctp_mem",
62 .data = &sysctl_sctp_mem,
63 .maxlen = sizeof(sysctl_sctp_mem),
64 .mode = 0644,
65 .proc_handler = proc_doulongvec_minmax
66 },
67 {
68 .procname = "sctp_rmem",
69 .data = &sysctl_sctp_rmem,
70 .maxlen = sizeof(sysctl_sctp_rmem),
71 .mode = 0644,
72 .proc_handler = proc_dointvec,
73 },
74 {
75 .procname = "sctp_wmem",
76 .data = &sysctl_sctp_wmem,
77 .maxlen = sizeof(sysctl_sctp_wmem),
78 .mode = 0644,
79 .proc_handler = proc_dointvec,
80 },
81
82 { /* sentinel */ }
83 };
84
85 static struct ctl_table sctp_net_table[] = {
86 {
87 .procname = "rto_initial",
88 .data = &init_net.sctp.rto_initial,
89 .maxlen = sizeof(unsigned int),
90 .mode = 0644,
91 .proc_handler = proc_dointvec_minmax,
92 .extra1 = SYSCTL_ONE,
93 .extra2 = &timer_max
94 },
95 {
96 .procname = "rto_min",
97 .data = &init_net.sctp.rto_min,
98 .maxlen = sizeof(unsigned int),
99 .mode = 0644,
100 .proc_handler = proc_sctp_do_rto_min,
101 .extra1 = SYSCTL_ONE,
102 .extra2 = &init_net.sctp.rto_max
103 },
104 {
105 .procname = "rto_max",
106 .data = &init_net.sctp.rto_max,
107 .maxlen = sizeof(unsigned int),
108 .mode = 0644,
109 .proc_handler = proc_sctp_do_rto_max,
110 .extra1 = &init_net.sctp.rto_min,
111 .extra2 = &timer_max
112 },
113 {
114 .procname = "rto_alpha_exp_divisor",
115 .data = &init_net.sctp.rto_alpha,
116 .maxlen = sizeof(int),
117 .mode = 0644,
118 .proc_handler = proc_sctp_do_alpha_beta,
119 .extra1 = &rto_alpha_min,
120 .extra2 = &rto_alpha_max,
121 },
122 {
123 .procname = "rto_beta_exp_divisor",
124 .data = &init_net.sctp.rto_beta,
125 .maxlen = sizeof(int),
126 .mode = 0644,
127 .proc_handler = proc_sctp_do_alpha_beta,
128 .extra1 = &rto_beta_min,
129 .extra2 = &rto_beta_max,
130 },
131 {
132 .procname = "max_burst",
133 .data = &init_net.sctp.max_burst,
134 .maxlen = sizeof(int),
135 .mode = 0644,
136 .proc_handler = proc_dointvec_minmax,
137 .extra1 = SYSCTL_ZERO,
138 .extra2 = SYSCTL_INT_MAX,
139 },
140 {
141 .procname = "cookie_preserve_enable",
142 .data = &init_net.sctp.cookie_preserve_enable,
143 .maxlen = sizeof(int),
144 .mode = 0644,
145 .proc_handler = proc_dointvec,
146 },
147 {
148 .procname = "cookie_hmac_alg",
149 .data = &init_net.sctp.sctp_hmac_alg,
150 .maxlen = 8,
151 .mode = 0644,
152 .proc_handler = proc_sctp_do_hmac_alg,
153 },
154 {
155 .procname = "valid_cookie_life",
156 .data = &init_net.sctp.valid_cookie_life,
157 .maxlen = sizeof(unsigned int),
158 .mode = 0644,
159 .proc_handler = proc_dointvec_minmax,
160 .extra1 = SYSCTL_ONE,
161 .extra2 = &timer_max
162 },
163 {
164 .procname = "sack_timeout",
165 .data = &init_net.sctp.sack_timeout,
166 .maxlen = sizeof(int),
167 .mode = 0644,
168 .proc_handler = proc_dointvec_minmax,
169 .extra1 = &sack_timer_min,
170 .extra2 = &sack_timer_max,
171 },
172 {
173 .procname = "hb_interval",
174 .data = &init_net.sctp.hb_interval,
175 .maxlen = sizeof(unsigned int),
176 .mode = 0644,
177 .proc_handler = proc_dointvec_minmax,
178 .extra1 = SYSCTL_ONE,
179 .extra2 = &timer_max
180 },
181 {
182 .procname = "association_max_retrans",
183 .data = &init_net.sctp.max_retrans_association,
184 .maxlen = sizeof(int),
185 .mode = 0644,
186 .proc_handler = proc_dointvec_minmax,
187 .extra1 = SYSCTL_ONE,
188 .extra2 = SYSCTL_INT_MAX,
189 },
190 {
191 .procname = "path_max_retrans",
192 .data = &init_net.sctp.max_retrans_path,
193 .maxlen = sizeof(int),
194 .mode = 0644,
195 .proc_handler = proc_dointvec_minmax,
196 .extra1 = SYSCTL_ONE,
197 .extra2 = SYSCTL_INT_MAX,
198 },
199 {
200 .procname = "max_init_retransmits",
201 .data = &init_net.sctp.max_retrans_init,
202 .maxlen = sizeof(int),
203 .mode = 0644,
204 .proc_handler = proc_dointvec_minmax,
205 .extra1 = SYSCTL_ONE,
206 .extra2 = SYSCTL_INT_MAX,
207 },
208 {
209 .procname = "pf_retrans",
210 .data = &init_net.sctp.pf_retrans,
211 .maxlen = sizeof(int),
212 .mode = 0644,
213 .proc_handler = proc_dointvec_minmax,
214 .extra1 = SYSCTL_ZERO,
215 .extra2 = SYSCTL_INT_MAX,
216 },
217 {
218 .procname = "sndbuf_policy",
219 .data = &init_net.sctp.sndbuf_policy,
220 .maxlen = sizeof(int),
221 .mode = 0644,
222 .proc_handler = proc_dointvec,
223 },
224 {
225 .procname = "rcvbuf_policy",
226 .data = &init_net.sctp.rcvbuf_policy,
227 .maxlen = sizeof(int),
228 .mode = 0644,
229 .proc_handler = proc_dointvec,
230 },
231 {
232 .procname = "default_auto_asconf",
233 .data = &init_net.sctp.default_auto_asconf,
234 .maxlen = sizeof(int),
235 .mode = 0644,
236 .proc_handler = proc_dointvec,
237 },
238 {
239 .procname = "addip_enable",
240 .data = &init_net.sctp.addip_enable,
241 .maxlen = sizeof(int),
242 .mode = 0644,
243 .proc_handler = proc_dointvec,
244 },
245 {
246 .procname = "addip_noauth_enable",
247 .data = &init_net.sctp.addip_noauth,
248 .maxlen = sizeof(int),
249 .mode = 0644,
250 .proc_handler = proc_dointvec,
251 },
252 {
253 .procname = "prsctp_enable",
254 .data = &init_net.sctp.prsctp_enable,
255 .maxlen = sizeof(int),
256 .mode = 0644,
257 .proc_handler = proc_dointvec,
258 },
259 {
260 .procname = "reconf_enable",
261 .data = &init_net.sctp.reconf_enable,
262 .maxlen = sizeof(int),
263 .mode = 0644,
264 .proc_handler = proc_dointvec,
265 },
266 {
267 .procname = "auth_enable",
268 .data = &init_net.sctp.auth_enable,
269 .maxlen = sizeof(int),
270 .mode = 0644,
271 .proc_handler = proc_sctp_do_auth,
272 },
273 {
274 .procname = "intl_enable",
275 .data = &init_net.sctp.intl_enable,
276 .maxlen = sizeof(int),
277 .mode = 0644,
278 .proc_handler = proc_dointvec,
279 },
280 {
281 .procname = "ecn_enable",
282 .data = &init_net.sctp.ecn_enable,
283 .maxlen = sizeof(int),
284 .mode = 0644,
285 .proc_handler = proc_dointvec,
286 },
287 {
288 .procname = "addr_scope_policy",
289 .data = &init_net.sctp.scope_policy,
290 .maxlen = sizeof(int),
291 .mode = 0644,
292 .proc_handler = proc_dointvec_minmax,
293 .extra1 = SYSCTL_ZERO,
294 .extra2 = &addr_scope_max,
295 },
296 {
297 .procname = "rwnd_update_shift",
298 .data = &init_net.sctp.rwnd_upd_shift,
299 .maxlen = sizeof(int),
300 .mode = 0644,
301 .proc_handler = &proc_dointvec_minmax,
302 .extra1 = SYSCTL_ONE,
303 .extra2 = &rwnd_scale_max,
304 },
305 {
306 .procname = "max_autoclose",
307 .data = &init_net.sctp.max_autoclose,
308 .maxlen = sizeof(unsigned long),
309 .mode = 0644,
310 .proc_handler = &proc_doulongvec_minmax,
311 .extra1 = &max_autoclose_min,
312 .extra2 = &max_autoclose_max,
313 },
314 {
315 .procname = "pf_enable",
316 .data = &init_net.sctp.pf_enable,
317 .maxlen = sizeof(int),
318 .mode = 0644,
319 .proc_handler = proc_dointvec,
320 },
321
322 { /* sentinel */ }
323 };
324
proc_sctp_do_hmac_alg(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)325 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
326 void __user *buffer, size_t *lenp,
327 loff_t *ppos)
328 {
329 struct net *net = current->nsproxy->net_ns;
330 struct ctl_table tbl;
331 bool changed = false;
332 char *none = "none";
333 char tmp[8] = {0};
334 int ret;
335
336 memset(&tbl, 0, sizeof(struct ctl_table));
337
338 if (write) {
339 tbl.data = tmp;
340 tbl.maxlen = sizeof(tmp);
341 } else {
342 tbl.data = net->sctp.sctp_hmac_alg ? : none;
343 tbl.maxlen = strlen(tbl.data);
344 }
345
346 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
347 if (write && ret == 0) {
348 #ifdef CONFIG_CRYPTO_MD5
349 if (!strncmp(tmp, "md5", 3)) {
350 net->sctp.sctp_hmac_alg = "md5";
351 changed = true;
352 }
353 #endif
354 #ifdef CONFIG_CRYPTO_SHA1
355 if (!strncmp(tmp, "sha1", 4)) {
356 net->sctp.sctp_hmac_alg = "sha1";
357 changed = true;
358 }
359 #endif
360 if (!strncmp(tmp, "none", 4)) {
361 net->sctp.sctp_hmac_alg = NULL;
362 changed = true;
363 }
364 if (!changed)
365 ret = -EINVAL;
366 }
367
368 return ret;
369 }
370
proc_sctp_do_rto_min(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)371 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
372 void __user *buffer, size_t *lenp,
373 loff_t *ppos)
374 {
375 struct net *net = current->nsproxy->net_ns;
376 unsigned int min = *(unsigned int *) ctl->extra1;
377 unsigned int max = *(unsigned int *) ctl->extra2;
378 struct ctl_table tbl;
379 int ret, new_value;
380
381 memset(&tbl, 0, sizeof(struct ctl_table));
382 tbl.maxlen = sizeof(unsigned int);
383
384 if (write)
385 tbl.data = &new_value;
386 else
387 tbl.data = &net->sctp.rto_min;
388
389 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
390 if (write && ret == 0) {
391 if (new_value > max || new_value < min)
392 return -EINVAL;
393
394 net->sctp.rto_min = new_value;
395 }
396
397 return ret;
398 }
399
proc_sctp_do_rto_max(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)400 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
401 void __user *buffer, size_t *lenp,
402 loff_t *ppos)
403 {
404 struct net *net = current->nsproxy->net_ns;
405 unsigned int min = *(unsigned int *) ctl->extra1;
406 unsigned int max = *(unsigned int *) ctl->extra2;
407 struct ctl_table tbl;
408 int ret, new_value;
409
410 memset(&tbl, 0, sizeof(struct ctl_table));
411 tbl.maxlen = sizeof(unsigned int);
412
413 if (write)
414 tbl.data = &new_value;
415 else
416 tbl.data = &net->sctp.rto_max;
417
418 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
419 if (write && ret == 0) {
420 if (new_value > max || new_value < min)
421 return -EINVAL;
422
423 net->sctp.rto_max = new_value;
424 }
425
426 return ret;
427 }
428
proc_sctp_do_alpha_beta(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)429 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
430 void __user *buffer, size_t *lenp,
431 loff_t *ppos)
432 {
433 if (write)
434 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
435 "suboptimal rtt/srtt estimations!\n");
436
437 return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
438 }
439
proc_sctp_do_auth(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)440 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
441 void __user *buffer, size_t *lenp,
442 loff_t *ppos)
443 {
444 struct net *net = current->nsproxy->net_ns;
445 struct ctl_table tbl;
446 int new_value, ret;
447
448 memset(&tbl, 0, sizeof(struct ctl_table));
449 tbl.maxlen = sizeof(unsigned int);
450
451 if (write)
452 tbl.data = &new_value;
453 else
454 tbl.data = &net->sctp.auth_enable;
455
456 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
457 if (write && ret == 0) {
458 struct sock *sk = net->sctp.ctl_sock;
459
460 net->sctp.auth_enable = new_value;
461 /* Update the value in the control socket */
462 lock_sock(sk);
463 sctp_sk(sk)->ep->auth_enable = new_value;
464 release_sock(sk);
465 }
466
467 return ret;
468 }
469
sctp_sysctl_net_register(struct net * net)470 int sctp_sysctl_net_register(struct net *net)
471 {
472 struct ctl_table *table;
473 int i;
474
475 table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
476 if (!table)
477 return -ENOMEM;
478
479 for (i = 0; table[i].data; i++)
480 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
481
482 net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
483 if (net->sctp.sysctl_header == NULL) {
484 kfree(table);
485 return -ENOMEM;
486 }
487 return 0;
488 }
489
sctp_sysctl_net_unregister(struct net * net)490 void sctp_sysctl_net_unregister(struct net *net)
491 {
492 struct ctl_table *table;
493
494 table = net->sctp.sysctl_header->ctl_table_arg;
495 unregister_net_sysctl_table(net->sctp.sysctl_header);
496 kfree(table);
497 }
498
499 static struct ctl_table_header *sctp_sysctl_header;
500
501 /* Sysctl registration. */
sctp_sysctl_register(void)502 void sctp_sysctl_register(void)
503 {
504 sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
505 }
506
507 /* Sysctl deregistration. */
sctp_sysctl_unregister(void)508 void sctp_sysctl_unregister(void)
509 {
510 unregister_net_sysctl_table(sctp_sysctl_header);
511 }
512