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 { /* sentinel */ }
313 };
314
proc_sctp_do_hmac_alg(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)315 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
316 void __user *buffer, size_t *lenp,
317 loff_t *ppos)
318 {
319 struct net *net = current->nsproxy->net_ns;
320 struct ctl_table tbl;
321 bool changed = false;
322 char *none = "none";
323 char tmp[8] = {0};
324 int ret;
325
326 memset(&tbl, 0, sizeof(struct ctl_table));
327
328 if (write) {
329 tbl.data = tmp;
330 tbl.maxlen = sizeof(tmp);
331 } else {
332 tbl.data = net->sctp.sctp_hmac_alg ? : none;
333 tbl.maxlen = strlen(tbl.data);
334 }
335
336 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
337 if (write && ret == 0) {
338 #ifdef CONFIG_CRYPTO_MD5
339 if (!strncmp(tmp, "md5", 3)) {
340 net->sctp.sctp_hmac_alg = "md5";
341 changed = true;
342 }
343 #endif
344 #ifdef CONFIG_CRYPTO_SHA1
345 if (!strncmp(tmp, "sha1", 4)) {
346 net->sctp.sctp_hmac_alg = "sha1";
347 changed = true;
348 }
349 #endif
350 if (!strncmp(tmp, "none", 4)) {
351 net->sctp.sctp_hmac_alg = NULL;
352 changed = true;
353 }
354 if (!changed)
355 ret = -EINVAL;
356 }
357
358 return ret;
359 }
360
proc_sctp_do_rto_min(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)361 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
362 void __user *buffer, size_t *lenp,
363 loff_t *ppos)
364 {
365 struct net *net = current->nsproxy->net_ns;
366 unsigned int min = *(unsigned int *) ctl->extra1;
367 unsigned int max = *(unsigned int *) ctl->extra2;
368 struct ctl_table tbl;
369 int ret, new_value;
370
371 memset(&tbl, 0, sizeof(struct ctl_table));
372 tbl.maxlen = sizeof(unsigned int);
373
374 if (write)
375 tbl.data = &new_value;
376 else
377 tbl.data = &net->sctp.rto_min;
378
379 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
380 if (write && ret == 0) {
381 if (new_value > max || new_value < min)
382 return -EINVAL;
383
384 net->sctp.rto_min = new_value;
385 }
386
387 return ret;
388 }
389
proc_sctp_do_rto_max(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)390 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
391 void __user *buffer, size_t *lenp,
392 loff_t *ppos)
393 {
394 struct net *net = current->nsproxy->net_ns;
395 unsigned int min = *(unsigned int *) ctl->extra1;
396 unsigned int max = *(unsigned int *) ctl->extra2;
397 struct ctl_table tbl;
398 int ret, new_value;
399
400 memset(&tbl, 0, sizeof(struct ctl_table));
401 tbl.maxlen = sizeof(unsigned int);
402
403 if (write)
404 tbl.data = &new_value;
405 else
406 tbl.data = &net->sctp.rto_max;
407
408 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
409 if (write && ret == 0) {
410 if (new_value > max || new_value < min)
411 return -EINVAL;
412
413 net->sctp.rto_max = new_value;
414 }
415
416 return ret;
417 }
418
proc_sctp_do_alpha_beta(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)419 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
420 void __user *buffer, size_t *lenp,
421 loff_t *ppos)
422 {
423 if (write)
424 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
425 "suboptimal rtt/srtt estimations!\n");
426
427 return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
428 }
429
proc_sctp_do_auth(struct ctl_table * ctl,int write,void __user * buffer,size_t * lenp,loff_t * ppos)430 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
431 void __user *buffer, size_t *lenp,
432 loff_t *ppos)
433 {
434 struct net *net = current->nsproxy->net_ns;
435 struct ctl_table tbl;
436 int new_value, ret;
437
438 memset(&tbl, 0, sizeof(struct ctl_table));
439 tbl.maxlen = sizeof(unsigned int);
440
441 if (write)
442 tbl.data = &new_value;
443 else
444 tbl.data = &net->sctp.auth_enable;
445
446 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
447 if (write && ret == 0) {
448 struct sock *sk = net->sctp.ctl_sock;
449
450 net->sctp.auth_enable = new_value;
451 /* Update the value in the control socket */
452 lock_sock(sk);
453 sctp_sk(sk)->ep->auth_enable = new_value;
454 release_sock(sk);
455 }
456
457 return ret;
458 }
459
sctp_sysctl_net_register(struct net * net)460 int sctp_sysctl_net_register(struct net *net)
461 {
462 struct ctl_table *table;
463 int i;
464
465 table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
466 if (!table)
467 return -ENOMEM;
468
469 for (i = 0; table[i].data; i++)
470 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
471
472 net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
473 if (net->sctp.sysctl_header == NULL) {
474 kfree(table);
475 return -ENOMEM;
476 }
477 return 0;
478 }
479
sctp_sysctl_net_unregister(struct net * net)480 void sctp_sysctl_net_unregister(struct net *net)
481 {
482 struct ctl_table *table;
483
484 table = net->sctp.sysctl_header->ctl_table_arg;
485 unregister_net_sysctl_table(net->sctp.sysctl_header);
486 kfree(table);
487 }
488
489 static struct ctl_table_header *sctp_sysctl_header;
490
491 /* Sysctl registration. */
sctp_sysctl_register(void)492 void sctp_sysctl_register(void)
493 {
494 sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
495 }
496
497 /* Sysctl deregistration. */
sctp_sysctl_unregister(void)498 void sctp_sysctl_unregister(void)
499 {
500 unregister_net_sysctl_table(sctp_sysctl_header);
501 }
502