1 /* SCTP kernel implementation
2 * (C) Copyright IBM Corp. 2002, 2004
3 * Copyright (c) 2002 Intel Corp.
4 *
5 * This file is part of the SCTP kernel implementation
6 *
7 * Sysctl related interfaces for SCTP.
8 *
9 * This SCTP implementation is free software;
10 * you can redistribute it and/or modify it under the terms of
11 * the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
13 * any later version.
14 *
15 * This SCTP implementation is distributed in the hope that it
16 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
17 * ************************
18 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
19 * See the GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with GNU CC; see the file COPYING. If not, see
23 * <http://www.gnu.org/licenses/>.
24 *
25 * Please send any bug reports or fixes you make to the
26 * email address(es):
27 * lksctp developers <linux-sctp@vger.kernel.org>
28 *
29 * Written or modified by:
30 * Mingqin Liu <liuming@us.ibm.com>
31 * Jon Grimm <jgrimm@us.ibm.com>
32 * Ardelle Fan <ardelle.fan@intel.com>
33 * Ryan Layer <rmlayer@us.ibm.com>
34 * Sridhar Samudrala <sri@us.ibm.com>
35 */
36
37 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
38
39 #include <net/sctp/structs.h>
40 #include <net/sctp/sctp.h>
41 #include <linux/sysctl.h>
42
43 static int zero = 0;
44 static int one = 1;
45 static int timer_max = 86400000; /* ms in one day */
46 static int int_max = INT_MAX;
47 static int sack_timer_min = 1;
48 static int sack_timer_max = 500;
49 static int addr_scope_max = 3; /* check sctp_scope_policy_t in include/net/sctp/constants.h for max entries */
50 static int rwnd_scale_max = 16;
51 static int rto_alpha_min = 0;
52 static int rto_beta_min = 0;
53 static int rto_alpha_max = 1000;
54 static int rto_beta_max = 1000;
55
56 static unsigned long max_autoclose_min = 0;
57 static unsigned long max_autoclose_max =
58 (MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
59 ? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
60
61 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
62 void __user *buffer, size_t *lenp,
63 loff_t *ppos);
64 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
65 void __user *buffer, size_t *lenp,
66 loff_t *ppos);
67 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
68 void __user *buffer, size_t *lenp,
69 loff_t *ppos);
70 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
71 void __user *buffer, size_t *lenp,
72 loff_t *ppos);
73 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
74 void __user *buffer, size_t *lenp,
75 loff_t *ppos);
76
77 static struct ctl_table sctp_table[] = {
78 {
79 .procname = "sctp_mem",
80 .data = &sysctl_sctp_mem,
81 .maxlen = sizeof(sysctl_sctp_mem),
82 .mode = 0644,
83 .proc_handler = proc_doulongvec_minmax
84 },
85 {
86 .procname = "sctp_rmem",
87 .data = &sysctl_sctp_rmem,
88 .maxlen = sizeof(sysctl_sctp_rmem),
89 .mode = 0644,
90 .proc_handler = proc_dointvec,
91 },
92 {
93 .procname = "sctp_wmem",
94 .data = &sysctl_sctp_wmem,
95 .maxlen = sizeof(sysctl_sctp_wmem),
96 .mode = 0644,
97 .proc_handler = proc_dointvec,
98 },
99
100 { /* sentinel */ }
101 };
102
103 static struct ctl_table sctp_net_table[] = {
104 {
105 .procname = "rto_initial",
106 .data = &init_net.sctp.rto_initial,
107 .maxlen = sizeof(unsigned int),
108 .mode = 0644,
109 .proc_handler = proc_dointvec_minmax,
110 .extra1 = &one,
111 .extra2 = &timer_max
112 },
113 {
114 .procname = "rto_min",
115 .data = &init_net.sctp.rto_min,
116 .maxlen = sizeof(unsigned int),
117 .mode = 0644,
118 .proc_handler = proc_sctp_do_rto_min,
119 .extra1 = &one,
120 .extra2 = &init_net.sctp.rto_max
121 },
122 {
123 .procname = "rto_max",
124 .data = &init_net.sctp.rto_max,
125 .maxlen = sizeof(unsigned int),
126 .mode = 0644,
127 .proc_handler = proc_sctp_do_rto_max,
128 .extra1 = &init_net.sctp.rto_min,
129 .extra2 = &timer_max
130 },
131 {
132 .procname = "rto_alpha_exp_divisor",
133 .data = &init_net.sctp.rto_alpha,
134 .maxlen = sizeof(int),
135 .mode = 0644,
136 .proc_handler = proc_sctp_do_alpha_beta,
137 .extra1 = &rto_alpha_min,
138 .extra2 = &rto_alpha_max,
139 },
140 {
141 .procname = "rto_beta_exp_divisor",
142 .data = &init_net.sctp.rto_beta,
143 .maxlen = sizeof(int),
144 .mode = 0644,
145 .proc_handler = proc_sctp_do_alpha_beta,
146 .extra1 = &rto_beta_min,
147 .extra2 = &rto_beta_max,
148 },
149 {
150 .procname = "max_burst",
151 .data = &init_net.sctp.max_burst,
152 .maxlen = sizeof(int),
153 .mode = 0644,
154 .proc_handler = proc_dointvec_minmax,
155 .extra1 = &zero,
156 .extra2 = &int_max
157 },
158 {
159 .procname = "cookie_preserve_enable",
160 .data = &init_net.sctp.cookie_preserve_enable,
161 .maxlen = sizeof(int),
162 .mode = 0644,
163 .proc_handler = proc_dointvec,
164 },
165 {
166 .procname = "cookie_hmac_alg",
167 .data = &init_net.sctp.sctp_hmac_alg,
168 .maxlen = 8,
169 .mode = 0644,
170 .proc_handler = proc_sctp_do_hmac_alg,
171 },
172 {
173 .procname = "valid_cookie_life",
174 .data = &init_net.sctp.valid_cookie_life,
175 .maxlen = sizeof(unsigned int),
176 .mode = 0644,
177 .proc_handler = proc_dointvec_minmax,
178 .extra1 = &one,
179 .extra2 = &timer_max
180 },
181 {
182 .procname = "sack_timeout",
183 .data = &init_net.sctp.sack_timeout,
184 .maxlen = sizeof(int),
185 .mode = 0644,
186 .proc_handler = proc_dointvec_minmax,
187 .extra1 = &sack_timer_min,
188 .extra2 = &sack_timer_max,
189 },
190 {
191 .procname = "hb_interval",
192 .data = &init_net.sctp.hb_interval,
193 .maxlen = sizeof(unsigned int),
194 .mode = 0644,
195 .proc_handler = proc_dointvec_minmax,
196 .extra1 = &one,
197 .extra2 = &timer_max
198 },
199 {
200 .procname = "association_max_retrans",
201 .data = &init_net.sctp.max_retrans_association,
202 .maxlen = sizeof(int),
203 .mode = 0644,
204 .proc_handler = proc_dointvec_minmax,
205 .extra1 = &one,
206 .extra2 = &int_max
207 },
208 {
209 .procname = "path_max_retrans",
210 .data = &init_net.sctp.max_retrans_path,
211 .maxlen = sizeof(int),
212 .mode = 0644,
213 .proc_handler = proc_dointvec_minmax,
214 .extra1 = &one,
215 .extra2 = &int_max
216 },
217 {
218 .procname = "max_init_retransmits",
219 .data = &init_net.sctp.max_retrans_init,
220 .maxlen = sizeof(int),
221 .mode = 0644,
222 .proc_handler = proc_dointvec_minmax,
223 .extra1 = &one,
224 .extra2 = &int_max
225 },
226 {
227 .procname = "pf_retrans",
228 .data = &init_net.sctp.pf_retrans,
229 .maxlen = sizeof(int),
230 .mode = 0644,
231 .proc_handler = proc_dointvec_minmax,
232 .extra1 = &zero,
233 .extra2 = &int_max
234 },
235 {
236 .procname = "sndbuf_policy",
237 .data = &init_net.sctp.sndbuf_policy,
238 .maxlen = sizeof(int),
239 .mode = 0644,
240 .proc_handler = proc_dointvec,
241 },
242 {
243 .procname = "rcvbuf_policy",
244 .data = &init_net.sctp.rcvbuf_policy,
245 .maxlen = sizeof(int),
246 .mode = 0644,
247 .proc_handler = proc_dointvec,
248 },
249 {
250 .procname = "default_auto_asconf",
251 .data = &init_net.sctp.default_auto_asconf,
252 .maxlen = sizeof(int),
253 .mode = 0644,
254 .proc_handler = proc_dointvec,
255 },
256 {
257 .procname = "addip_enable",
258 .data = &init_net.sctp.addip_enable,
259 .maxlen = sizeof(int),
260 .mode = 0644,
261 .proc_handler = proc_dointvec,
262 },
263 {
264 .procname = "addip_noauth_enable",
265 .data = &init_net.sctp.addip_noauth,
266 .maxlen = sizeof(int),
267 .mode = 0644,
268 .proc_handler = proc_dointvec,
269 },
270 {
271 .procname = "prsctp_enable",
272 .data = &init_net.sctp.prsctp_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 = "addr_scope_policy",
286 .data = &init_net.sctp.scope_policy,
287 .maxlen = sizeof(int),
288 .mode = 0644,
289 .proc_handler = proc_dointvec_minmax,
290 .extra1 = &zero,
291 .extra2 = &addr_scope_max,
292 },
293 {
294 .procname = "rwnd_update_shift",
295 .data = &init_net.sctp.rwnd_upd_shift,
296 .maxlen = sizeof(int),
297 .mode = 0644,
298 .proc_handler = &proc_dointvec_minmax,
299 .extra1 = &one,
300 .extra2 = &rwnd_scale_max,
301 },
302 {
303 .procname = "max_autoclose",
304 .data = &init_net.sctp.max_autoclose,
305 .maxlen = sizeof(unsigned long),
306 .mode = 0644,
307 .proc_handler = &proc_doulongvec_minmax,
308 .extra1 = &max_autoclose_min,
309 .extra2 = &max_autoclose_max,
310 },
311 {
312 .procname = "pf_enable",
313 .data = &init_net.sctp.pf_enable,
314 .maxlen = sizeof(int),
315 .mode = 0644,
316 .proc_handler = proc_dointvec,
317 },
318
319 { /* sentinel */ }
320 };
321
proc_sctp_do_hmac_alg(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)322 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
323 void __user *buffer, size_t *lenp,
324 loff_t *ppos)
325 {
326 struct net *net = current->nsproxy->net_ns;
327 struct ctl_table tbl;
328 bool changed = false;
329 char *none = "none";
330 char tmp[8] = {0};
331 int ret;
332
333 memset(&tbl, 0, sizeof(struct ctl_table));
334
335 if (write) {
336 tbl.data = tmp;
337 tbl.maxlen = sizeof(tmp);
338 } else {
339 tbl.data = net->sctp.sctp_hmac_alg ? : none;
340 tbl.maxlen = strlen(tbl.data);
341 }
342
343 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
344 if (write && ret == 0) {
345 #ifdef CONFIG_CRYPTO_MD5
346 if (!strncmp(tmp, "md5", 3)) {
347 net->sctp.sctp_hmac_alg = "md5";
348 changed = true;
349 }
350 #endif
351 #ifdef CONFIG_CRYPTO_SHA1
352 if (!strncmp(tmp, "sha1", 4)) {
353 net->sctp.sctp_hmac_alg = "sha1";
354 changed = true;
355 }
356 #endif
357 if (!strncmp(tmp, "none", 4)) {
358 net->sctp.sctp_hmac_alg = NULL;
359 changed = true;
360 }
361 if (!changed)
362 ret = -EINVAL;
363 }
364
365 return ret;
366 }
367
proc_sctp_do_rto_min(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)368 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
369 void __user *buffer, size_t *lenp,
370 loff_t *ppos)
371 {
372 struct net *net = current->nsproxy->net_ns;
373 unsigned int min = *(unsigned int *) ctl->extra1;
374 unsigned int max = *(unsigned int *) ctl->extra2;
375 struct ctl_table tbl;
376 int ret, new_value;
377
378 memset(&tbl, 0, sizeof(struct ctl_table));
379 tbl.maxlen = sizeof(unsigned int);
380
381 if (write)
382 tbl.data = &new_value;
383 else
384 tbl.data = &net->sctp.rto_min;
385
386 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
387 if (write && ret == 0) {
388 if (new_value > max || new_value < min)
389 return -EINVAL;
390
391 net->sctp.rto_min = new_value;
392 }
393
394 return ret;
395 }
396
proc_sctp_do_rto_max(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)397 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
398 void __user *buffer, size_t *lenp,
399 loff_t *ppos)
400 {
401 struct net *net = current->nsproxy->net_ns;
402 unsigned int min = *(unsigned int *) ctl->extra1;
403 unsigned int max = *(unsigned int *) ctl->extra2;
404 struct ctl_table tbl;
405 int ret, new_value;
406
407 memset(&tbl, 0, sizeof(struct ctl_table));
408 tbl.maxlen = sizeof(unsigned int);
409
410 if (write)
411 tbl.data = &new_value;
412 else
413 tbl.data = &net->sctp.rto_max;
414
415 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
416 if (write && ret == 0) {
417 if (new_value > max || new_value < min)
418 return -EINVAL;
419
420 net->sctp.rto_max = new_value;
421 }
422
423 return ret;
424 }
425
proc_sctp_do_alpha_beta(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)426 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
427 void __user *buffer, size_t *lenp,
428 loff_t *ppos)
429 {
430 if (write)
431 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
432 "suboptimal rtt/srtt estimations!\n");
433
434 return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
435 }
436
proc_sctp_do_auth(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)437 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
438 void __user *buffer, size_t *lenp,
439 loff_t *ppos)
440 {
441 struct net *net = current->nsproxy->net_ns;
442 struct ctl_table tbl;
443 int new_value, ret;
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.auth_enable;
452
453 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
454 if (write && ret == 0) {
455 struct sock *sk = net->sctp.ctl_sock;
456
457 net->sctp.auth_enable = new_value;
458 /* Update the value in the control socket */
459 lock_sock(sk);
460 sctp_sk(sk)->ep->auth_enable = new_value;
461 release_sock(sk);
462 }
463
464 return ret;
465 }
466
sctp_sysctl_net_register(struct net * net)467 int sctp_sysctl_net_register(struct net *net)
468 {
469 struct ctl_table *table;
470 int i;
471
472 table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
473 if (!table)
474 return -ENOMEM;
475
476 for (i = 0; table[i].data; i++)
477 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
478
479 net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
480 if (net->sctp.sysctl_header == NULL) {
481 kfree(table);
482 return -ENOMEM;
483 }
484 return 0;
485 }
486
sctp_sysctl_net_unregister(struct net * net)487 void sctp_sysctl_net_unregister(struct net *net)
488 {
489 struct ctl_table *table;
490
491 table = net->sctp.sysctl_header->ctl_table_arg;
492 unregister_net_sysctl_table(net->sctp.sysctl_header);
493 kfree(table);
494 }
495
496 static struct ctl_table_header *sctp_sysctl_header;
497
498 /* Sysctl registration. */
sctp_sysctl_register(void)499 void sctp_sysctl_register(void)
500 {
501 sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
502 }
503
504 /* Sysctl deregistration. */
sctp_sysctl_unregister(void)505 void sctp_sysctl_unregister(void)
506 {
507 unregister_net_sysctl_table(sctp_sysctl_header);
508 }
509