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60c778b2 1/* SCTP kernel implementation
1da177e4
LT
2 * (C) Copyright IBM Corp. 2002, 2004
3 * Copyright (c) 2002 Intel Corp.
4 *
60c778b2 5 * This file is part of the SCTP kernel implementation
1da177e4
LT
6 *
7 * Sysctl related interfaces for SCTP.
8 *
60c778b2 9 * This SCTP implementation is free software;
1da177e4
LT
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 *
60c778b2 15 * This SCTP implementation is distributed in the hope that it
1da177e4
LT
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
4b2f13a2
JK
22 * along with GNU CC; see the file COPYING. If not, see
23 * <http://www.gnu.org/licenses/>.
1da177e4
LT
24 *
25 * Please send any bug reports or fixes you make to the
26 * email address(es):
91705c61 27 * lksctp developers <linux-sctp@vger.kernel.org>
1da177e4 28 *
1da177e4
LT
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>
1da177e4
LT
35 */
36
b58537a1
DB
37#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
38
1da177e4 39#include <net/sctp/structs.h>
8c5955d8 40#include <net/sctp/sctp.h>
1da177e4
LT
41#include <linux/sysctl.h>
42
3fd091e7
VY
43static int zero = 0;
44static int one = 1;
45static int timer_max = 86400000; /* ms in one day */
46static int int_max = INT_MAX;
d48e074d
JMG
47static int sack_timer_min = 1;
48static int sack_timer_max = 500;
72388433 49static int addr_scope_max = 3; /* check sctp_scope_policy_t in include/net/sctp/constants.h for max entries */
90f2f531 50static int rwnd_scale_max = 16;
b58537a1
DB
51static int rto_alpha_min = 0;
52static int rto_beta_min = 0;
53static int rto_alpha_max = 1000;
54static int rto_beta_max = 1000;
55
2692ba61
XW
56static unsigned long max_autoclose_min = 0;
57static unsigned long max_autoclose_max =
58 (MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
59 ? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
1da177e4 60
b486b228 61static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
3c68198e 62 void __user *buffer, size_t *lenp,
3c68198e 63 loff_t *ppos);
4f3fdf3b 64static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
65 void __user *buffer, size_t *lenp,
66 loff_t *ppos);
67static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
3c68198e 68 void __user *buffer, size_t *lenp,
3c68198e 69 loff_t *ppos);
b58537a1
DB
70static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
71 void __user *buffer, size_t *lenp,
72 loff_t *ppos);
b14878cc
VY
73static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
74 void __user *buffer, size_t *lenp,
75 loff_t *ppos);
4f3fdf3b 76
fe2c6338 77static struct ctl_table sctp_table[] = {
e1fc3b14
EB
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
fe2c6338 103static struct ctl_table sctp_net_table[] = {
1da177e4 104 {
1da177e4 105 .procname = "rto_initial",
e1fc3b14 106 .data = &init_net.sctp.rto_initial,
3fd091e7 107 .maxlen = sizeof(unsigned int),
1da177e4 108 .mode = 0644,
6d9f239a 109 .proc_handler = proc_dointvec_minmax,
3fd091e7
VY
110 .extra1 = &one,
111 .extra2 = &timer_max
1da177e4
LT
112 },
113 {
1da177e4 114 .procname = "rto_min",
e1fc3b14 115 .data = &init_net.sctp.rto_min,
3fd091e7 116 .maxlen = sizeof(unsigned int),
1da177e4 117 .mode = 0644,
4f3fdf3b 118 .proc_handler = proc_sctp_do_rto_min,
3fd091e7 119 .extra1 = &one,
4f3fdf3b 120 .extra2 = &init_net.sctp.rto_max
1da177e4
LT
121 },
122 {
1da177e4 123 .procname = "rto_max",
e1fc3b14 124 .data = &init_net.sctp.rto_max,
3fd091e7 125 .maxlen = sizeof(unsigned int),
1da177e4 126 .mode = 0644,
4f3fdf3b 127 .proc_handler = proc_sctp_do_rto_max,
128 .extra1 = &init_net.sctp.rto_min,
3fd091e7 129 .extra2 = &timer_max
1da177e4
LT
130 },
131 {
e1fc3b14
EB
132 .procname = "rto_alpha_exp_divisor",
133 .data = &init_net.sctp.rto_alpha,
134 .maxlen = sizeof(int),
b58537a1
DB
135 .mode = 0644,
136 .proc_handler = proc_sctp_do_alpha_beta,
137 .extra1 = &rto_alpha_min,
138 .extra2 = &rto_alpha_max,
e1fc3b14
EB
139 },
140 {
141 .procname = "rto_beta_exp_divisor",
142 .data = &init_net.sctp.rto_beta,
143 .maxlen = sizeof(int),
b58537a1
DB
144 .mode = 0644,
145 .proc_handler = proc_sctp_do_alpha_beta,
146 .extra1 = &rto_beta_min,
147 .extra2 = &rto_beta_max,
1da177e4
LT
148 },
149 {
1da177e4 150 .procname = "max_burst",
e1fc3b14 151 .data = &init_net.sctp.max_burst,
1da177e4
LT
152 .maxlen = sizeof(int),
153 .mode = 0644,
6d9f239a 154 .proc_handler = proc_dointvec_minmax,
3fd091e7
VY
155 .extra1 = &zero,
156 .extra2 = &int_max
1da177e4
LT
157 },
158 {
e1fc3b14
EB
159 .procname = "cookie_preserve_enable",
160 .data = &init_net.sctp.cookie_preserve_enable,
1da177e4
LT
161 .maxlen = sizeof(int),
162 .mode = 0644,
e1fc3b14
EB
163 .proc_handler = proc_dointvec,
164 },
3c68198e
NH
165 {
166 .procname = "cookie_hmac_alg",
22a1f514 167 .data = &init_net.sctp.sctp_hmac_alg,
3c68198e
NH
168 .maxlen = 8,
169 .mode = 0644,
170 .proc_handler = proc_sctp_do_hmac_alg,
171 },
e1fc3b14
EB
172 {
173 .procname = "valid_cookie_life",
174 .data = &init_net.sctp.valid_cookie_life,
175 .maxlen = sizeof(unsigned int),
176 .mode = 0644,
6d9f239a 177 .proc_handler = proc_dointvec_minmax,
e1fc3b14
EB
178 .extra1 = &one,
179 .extra2 = &timer_max
1da177e4 180 },
4eb701df 181 {
e1fc3b14
EB
182 .procname = "sack_timeout",
183 .data = &init_net.sctp.sack_timeout,
4eb701df
NH
184 .maxlen = sizeof(int),
185 .mode = 0644,
e1fc3b14
EB
186 .proc_handler = proc_dointvec_minmax,
187 .extra1 = &sack_timer_min,
188 .extra2 = &sack_timer_max,
4eb701df 189 },
049b3ff5 190 {
e1fc3b14
EB
191 .procname = "hb_interval",
192 .data = &init_net.sctp.hb_interval,
193 .maxlen = sizeof(unsigned int),
049b3ff5 194 .mode = 0644,
e1fc3b14
EB
195 .proc_handler = proc_dointvec_minmax,
196 .extra1 = &one,
197 .extra2 = &timer_max
049b3ff5 198 },
1da177e4 199 {
e1fc3b14
EB
200 .procname = "association_max_retrans",
201 .data = &init_net.sctp.max_retrans_association,
1da177e4
LT
202 .maxlen = sizeof(int),
203 .mode = 0644,
6d9f239a 204 .proc_handler = proc_dointvec_minmax,
3fd091e7
VY
205 .extra1 = &one,
206 .extra2 = &int_max
1da177e4 207 },
5aa93bcf 208 {
e1fc3b14
EB
209 .procname = "path_max_retrans",
210 .data = &init_net.sctp.max_retrans_path,
5aa93bcf
NH
211 .maxlen = sizeof(int),
212 .mode = 0644,
213 .proc_handler = proc_dointvec_minmax,
e1fc3b14 214 .extra1 = &one,
5aa93bcf
NH
215 .extra2 = &int_max
216 },
1da177e4 217 {
1da177e4 218 .procname = "max_init_retransmits",
e1fc3b14 219 .data = &init_net.sctp.max_retrans_init,
1da177e4
LT
220 .maxlen = sizeof(int),
221 .mode = 0644,
6d9f239a 222 .proc_handler = proc_dointvec_minmax,
3fd091e7
VY
223 .extra1 = &one,
224 .extra2 = &int_max
1da177e4
LT
225 },
226 {
e1fc3b14
EB
227 .procname = "pf_retrans",
228 .data = &init_net.sctp.pf_retrans,
229 .maxlen = sizeof(int),
1da177e4 230 .mode = 0644,
6d9f239a 231 .proc_handler = proc_dointvec_minmax,
e1fc3b14
EB
232 .extra1 = &zero,
233 .extra2 = &int_max
1da177e4
LT
234 },
235 {
e1fc3b14
EB
236 .procname = "sndbuf_policy",
237 .data = &init_net.sctp.sndbuf_policy,
8116ffad 238 .maxlen = sizeof(int),
1da177e4 239 .mode = 0644,
6d9f239a 240 .proc_handler = proc_dointvec,
1da177e4
LT
241 },
242 {
e1fc3b14
EB
243 .procname = "rcvbuf_policy",
244 .data = &init_net.sctp.rcvbuf_policy,
dd51be0f
MH
245 .maxlen = sizeof(int),
246 .mode = 0644,
247 .proc_handler = proc_dointvec,
248 },
249 {
250 .procname = "default_auto_asconf",
e1fc3b14 251 .data = &init_net.sctp.default_auto_asconf,
1da177e4
LT
252 .maxlen = sizeof(int),
253 .mode = 0644,
6d9f239a 254 .proc_handler = proc_dointvec,
1da177e4
LT
255 },
256 {
e1fc3b14
EB
257 .procname = "addip_enable",
258 .data = &init_net.sctp.addip_enable,
1da177e4
LT
259 .maxlen = sizeof(int),
260 .mode = 0644,
6d9f239a 261 .proc_handler = proc_dointvec,
1da177e4 262 },
2f85a429 263 {
e1fc3b14
EB
264 .procname = "addip_noauth_enable",
265 .data = &init_net.sctp.addip_noauth,
d48e074d 266 .maxlen = sizeof(int),
2f85a429 267 .mode = 0644,
6d9f239a 268 .proc_handler = proc_dointvec,
4d93df0a
NH
269 },
270 {
e1fc3b14
EB
271 .procname = "prsctp_enable",
272 .data = &init_net.sctp.prsctp_enable,
a29a5bd4
VY
273 .maxlen = sizeof(int),
274 .mode = 0644,
6d9f239a 275 .proc_handler = proc_dointvec,
a29a5bd4 276 },
73d9c4fd 277 {
e1fc3b14
EB
278 .procname = "auth_enable",
279 .data = &init_net.sctp.auth_enable,
73d9c4fd
VY
280 .maxlen = sizeof(int),
281 .mode = 0644,
b14878cc 282 .proc_handler = proc_sctp_do_auth,
73d9c4fd 283 },
72388433 284 {
72388433 285 .procname = "addr_scope_policy",
e1fc3b14 286 .data = &init_net.sctp.scope_policy,
72388433
BD
287 .maxlen = sizeof(int),
288 .mode = 0644,
6d456111 289 .proc_handler = proc_dointvec_minmax,
72388433
BD
290 .extra1 = &zero,
291 .extra2 = &addr_scope_max,
292 },
90f2f531 293 {
90f2f531 294 .procname = "rwnd_update_shift",
e1fc3b14 295 .data = &init_net.sctp.rwnd_upd_shift,
90f2f531
VY
296 .maxlen = sizeof(int),
297 .mode = 0644,
298 .proc_handler = &proc_dointvec_minmax,
90f2f531
VY
299 .extra1 = &one,
300 .extra2 = &rwnd_scale_max,
301 },
2692ba61
XW
302 {
303 .procname = "max_autoclose",
e1fc3b14 304 .data = &init_net.sctp.max_autoclose,
2692ba61
XW
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 },
71acc0dd 311
d7fc02c7 312 { /* sentinel */ }
1da177e4
LT
313};
314
b486b228 315static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
3c68198e
NH
316 void __user *buffer, size_t *lenp,
317 loff_t *ppos)
318{
319 struct net *net = current->nsproxy->net_ns;
fe2c6338 320 struct ctl_table tbl;
ff5e92c1 321 bool changed = false;
3c68198e 322 char *none = "none";
320f1a4a 323 char tmp[8] = {0};
ff5e92c1 324 int ret;
3c68198e
NH
325
326 memset(&tbl, 0, sizeof(struct ctl_table));
327
328 if (write) {
329 tbl.data = tmp;
ff5e92c1 330 tbl.maxlen = sizeof(tmp);
3c68198e
NH
331 } else {
332 tbl.data = net->sctp.sctp_hmac_alg ? : none;
333 tbl.maxlen = strlen(tbl.data);
334 }
3c68198e 335
ff5e92c1
DB
336 ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
337 if (write && ret == 0) {
3c68198e
NH
338#ifdef CONFIG_CRYPTO_MD5
339 if (!strncmp(tmp, "md5", 3)) {
340 net->sctp.sctp_hmac_alg = "md5";
ff5e92c1 341 changed = true;
3c68198e
NH
342 }
343#endif
344#ifdef CONFIG_CRYPTO_SHA1
345 if (!strncmp(tmp, "sha1", 4)) {
346 net->sctp.sctp_hmac_alg = "sha1";
ff5e92c1 347 changed = true;
3c68198e
NH
348 }
349#endif
350 if (!strncmp(tmp, "none", 4)) {
351 net->sctp.sctp_hmac_alg = NULL;
ff5e92c1 352 changed = true;
3c68198e 353 }
3c68198e
NH
354 if (!changed)
355 ret = -EINVAL;
356 }
357
358 return ret;
359}
360
4f3fdf3b 361static 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;
4f3fdf3b 366 unsigned int min = *(unsigned int *) ctl->extra1;
367 unsigned int max = *(unsigned int *) ctl->extra2;
ff5e92c1
DB
368 struct ctl_table tbl;
369 int ret, new_value;
4f3fdf3b 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;
ff5e92c1 378
4f3fdf3b 379 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
ff5e92c1
DB
380 if (write && ret == 0) {
381 if (new_value > max || new_value < min)
4f3fdf3b 382 return -EINVAL;
ff5e92c1 383
4f3fdf3b 384 net->sctp.rto_min = new_value;
385 }
ff5e92c1 386
4f3fdf3b 387 return ret;
388}
389
390static 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;
4f3fdf3b 395 unsigned int min = *(unsigned int *) ctl->extra1;
396 unsigned int max = *(unsigned int *) ctl->extra2;
ff5e92c1
DB
397 struct ctl_table tbl;
398 int ret, new_value;
4f3fdf3b 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;
ff5e92c1 407
4f3fdf3b 408 ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
ff5e92c1
DB
409 if (write && ret == 0) {
410 if (new_value > max || new_value < min)
4f3fdf3b 411 return -EINVAL;
ff5e92c1 412
4f3fdf3b 413 net->sctp.rto_max = new_value;
414 }
ff5e92c1 415
4f3fdf3b 416 return ret;
417}
418
b58537a1
DB
419static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
420 void __user *buffer, size_t *lenp,
421 loff_t *ppos)
422{
eaea2da7
DB
423 if (write)
424 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
425 "suboptimal rtt/srtt estimations!\n");
b58537a1
DB
426
427 return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
428}
429
b14878cc
VY
430static 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);
24599e61 447 if (write && ret == 0) {
b14878cc
VY
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
ebb7e95d
EB
460int sctp_sysctl_net_register(struct net *net)
461{
eb9f3705 462 struct ctl_table *table;
463 int i;
ebb7e95d 464
eb9f3705 465 table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
466 if (!table)
467 return -ENOMEM;
ebb7e95d 468
eb9f3705 469 for (i = 0; table[i].data; i++)
470 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
e1fc3b14 471
ebb7e95d 472 net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
f66138c8 473 if (net->sctp.sysctl_header == NULL) {
474 kfree(table);
475 return -ENOMEM;
476 }
ebb7e95d
EB
477 return 0;
478}
479
480void sctp_sysctl_net_unregister(struct net *net)
481{
5f19d121
VY
482 struct ctl_table *table;
483
484 table = net->sctp.sysctl_header->ctl_table_arg;
ebb7e95d 485 unregister_net_sysctl_table(net->sctp.sysctl_header);
5f19d121 486 kfree(table);
ebb7e95d
EB
487}
488
26ac8e5f 489static struct ctl_table_header *sctp_sysctl_header;
1da177e4
LT
490
491/* Sysctl registration. */
492void sctp_sysctl_register(void)
493{
ec8f23ce 494 sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
1da177e4
LT
495}
496
497/* Sysctl deregistration. */
498void sctp_sysctl_unregister(void)
499{
5dd3df10 500 unregister_net_sysctl_table(sctp_sysctl_header);
1da177e4 501}