xref: /linux/net/sctp/sysctl.c (revision 9e9f60108423f18a99c9cc93ef7f23490ecc709b)
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 extern long sysctl_sctp_mem[3];
62 extern int sysctl_sctp_rmem[3];
63 extern int sysctl_sctp_wmem[3];
64 
65 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
66 				void __user *buffer, size_t *lenp,
67 				loff_t *ppos);
68 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
69 				void __user *buffer, size_t *lenp,
70 				loff_t *ppos);
71 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
72 				void __user *buffer, size_t *lenp,
73 				loff_t *ppos);
74 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
75 				   void __user *buffer, size_t *lenp,
76 				   loff_t *ppos);
77 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
78 			     void __user *buffer, size_t *lenp,
79 			     loff_t *ppos);
80 
81 static struct ctl_table sctp_table[] = {
82 	{
83 		.procname	= "sctp_mem",
84 		.data		= &sysctl_sctp_mem,
85 		.maxlen		= sizeof(sysctl_sctp_mem),
86 		.mode		= 0644,
87 		.proc_handler	= proc_doulongvec_minmax
88 	},
89 	{
90 		.procname	= "sctp_rmem",
91 		.data		= &sysctl_sctp_rmem,
92 		.maxlen		= sizeof(sysctl_sctp_rmem),
93 		.mode		= 0644,
94 		.proc_handler	= proc_dointvec,
95 	},
96 	{
97 		.procname	= "sctp_wmem",
98 		.data		= &sysctl_sctp_wmem,
99 		.maxlen		= sizeof(sysctl_sctp_wmem),
100 		.mode		= 0644,
101 		.proc_handler	= proc_dointvec,
102 	},
103 
104 	{ /* sentinel */ }
105 };
106 
107 static struct ctl_table sctp_net_table[] = {
108 	{
109 		.procname	= "rto_initial",
110 		.data		= &init_net.sctp.rto_initial,
111 		.maxlen		= sizeof(unsigned int),
112 		.mode		= 0644,
113 		.proc_handler	= proc_dointvec_minmax,
114 		.extra1         = &one,
115 		.extra2         = &timer_max
116 	},
117 	{
118 		.procname	= "rto_min",
119 		.data		= &init_net.sctp.rto_min,
120 		.maxlen		= sizeof(unsigned int),
121 		.mode		= 0644,
122 		.proc_handler	= proc_sctp_do_rto_min,
123 		.extra1         = &one,
124 		.extra2         = &init_net.sctp.rto_max
125 	},
126 	{
127 		.procname	= "rto_max",
128 		.data		= &init_net.sctp.rto_max,
129 		.maxlen		= sizeof(unsigned int),
130 		.mode		= 0644,
131 		.proc_handler	= proc_sctp_do_rto_max,
132 		.extra1         = &init_net.sctp.rto_min,
133 		.extra2         = &timer_max
134 	},
135 	{
136 		.procname	= "rto_alpha_exp_divisor",
137 		.data		= &init_net.sctp.rto_alpha,
138 		.maxlen		= sizeof(int),
139 		.mode		= 0644,
140 		.proc_handler	= proc_sctp_do_alpha_beta,
141 		.extra1		= &rto_alpha_min,
142 		.extra2		= &rto_alpha_max,
143 	},
144 	{
145 		.procname	= "rto_beta_exp_divisor",
146 		.data		= &init_net.sctp.rto_beta,
147 		.maxlen		= sizeof(int),
148 		.mode		= 0644,
149 		.proc_handler	= proc_sctp_do_alpha_beta,
150 		.extra1		= &rto_beta_min,
151 		.extra2		= &rto_beta_max,
152 	},
153 	{
154 		.procname	= "max_burst",
155 		.data		= &init_net.sctp.max_burst,
156 		.maxlen		= sizeof(int),
157 		.mode		= 0644,
158 		.proc_handler	= proc_dointvec_minmax,
159 		.extra1		= &zero,
160 		.extra2		= &int_max
161 	},
162 	{
163 		.procname	= "cookie_preserve_enable",
164 		.data		= &init_net.sctp.cookie_preserve_enable,
165 		.maxlen		= sizeof(int),
166 		.mode		= 0644,
167 		.proc_handler	= proc_dointvec,
168 	},
169 	{
170 		.procname	= "cookie_hmac_alg",
171 		.data		= &init_net.sctp.sctp_hmac_alg,
172 		.maxlen		= 8,
173 		.mode		= 0644,
174 		.proc_handler	= proc_sctp_do_hmac_alg,
175 	},
176 	{
177 		.procname	= "valid_cookie_life",
178 		.data		= &init_net.sctp.valid_cookie_life,
179 		.maxlen		= sizeof(unsigned int),
180 		.mode		= 0644,
181 		.proc_handler	= proc_dointvec_minmax,
182 		.extra1         = &one,
183 		.extra2         = &timer_max
184 	},
185 	{
186 		.procname	= "sack_timeout",
187 		.data		= &init_net.sctp.sack_timeout,
188 		.maxlen		= sizeof(int),
189 		.mode		= 0644,
190 		.proc_handler	= proc_dointvec_minmax,
191 		.extra1         = &sack_timer_min,
192 		.extra2         = &sack_timer_max,
193 	},
194 	{
195 		.procname	= "hb_interval",
196 		.data		= &init_net.sctp.hb_interval,
197 		.maxlen		= sizeof(unsigned int),
198 		.mode		= 0644,
199 		.proc_handler	= proc_dointvec_minmax,
200 		.extra1         = &one,
201 		.extra2         = &timer_max
202 	},
203 	{
204 		.procname	= "association_max_retrans",
205 		.data		= &init_net.sctp.max_retrans_association,
206 		.maxlen		= sizeof(int),
207 		.mode		= 0644,
208 		.proc_handler	= proc_dointvec_minmax,
209 		.extra1		= &one,
210 		.extra2		= &int_max
211 	},
212 	{
213 		.procname	= "path_max_retrans",
214 		.data		= &init_net.sctp.max_retrans_path,
215 		.maxlen		= sizeof(int),
216 		.mode		= 0644,
217 		.proc_handler	= proc_dointvec_minmax,
218 		.extra1		= &one,
219 		.extra2		= &int_max
220 	},
221 	{
222 		.procname	= "max_init_retransmits",
223 		.data		= &init_net.sctp.max_retrans_init,
224 		.maxlen		= sizeof(int),
225 		.mode		= 0644,
226 		.proc_handler	= proc_dointvec_minmax,
227 		.extra1		= &one,
228 		.extra2		= &int_max
229 	},
230 	{
231 		.procname	= "pf_retrans",
232 		.data		= &init_net.sctp.pf_retrans,
233 		.maxlen		= sizeof(int),
234 		.mode		= 0644,
235 		.proc_handler	= proc_dointvec_minmax,
236 		.extra1		= &zero,
237 		.extra2		= &int_max
238 	},
239 	{
240 		.procname	= "sndbuf_policy",
241 		.data		= &init_net.sctp.sndbuf_policy,
242 		.maxlen		= sizeof(int),
243 		.mode		= 0644,
244 		.proc_handler	= proc_dointvec,
245 	},
246 	{
247 		.procname	= "rcvbuf_policy",
248 		.data		= &init_net.sctp.rcvbuf_policy,
249 		.maxlen		= sizeof(int),
250 		.mode		= 0644,
251 		.proc_handler	= proc_dointvec,
252 	},
253 	{
254 		.procname	= "default_auto_asconf",
255 		.data		= &init_net.sctp.default_auto_asconf,
256 		.maxlen		= sizeof(int),
257 		.mode		= 0644,
258 		.proc_handler	= proc_dointvec,
259 	},
260 	{
261 		.procname	= "addip_enable",
262 		.data		= &init_net.sctp.addip_enable,
263 		.maxlen		= sizeof(int),
264 		.mode		= 0644,
265 		.proc_handler	= proc_dointvec,
266 	},
267 	{
268 		.procname	= "addip_noauth_enable",
269 		.data		= &init_net.sctp.addip_noauth,
270 		.maxlen		= sizeof(int),
271 		.mode		= 0644,
272 		.proc_handler	= proc_dointvec,
273 	},
274 	{
275 		.procname	= "prsctp_enable",
276 		.data		= &init_net.sctp.prsctp_enable,
277 		.maxlen		= sizeof(int),
278 		.mode		= 0644,
279 		.proc_handler	= proc_dointvec,
280 	},
281 	{
282 		.procname	= "auth_enable",
283 		.data		= &init_net.sctp.auth_enable,
284 		.maxlen		= sizeof(int),
285 		.mode		= 0644,
286 		.proc_handler	= proc_sctp_do_auth,
287 	},
288 	{
289 		.procname	= "addr_scope_policy",
290 		.data		= &init_net.sctp.scope_policy,
291 		.maxlen		= sizeof(int),
292 		.mode		= 0644,
293 		.proc_handler	= proc_dointvec_minmax,
294 		.extra1		= &zero,
295 		.extra2		= &addr_scope_max,
296 	},
297 	{
298 		.procname	= "rwnd_update_shift",
299 		.data		= &init_net.sctp.rwnd_upd_shift,
300 		.maxlen		= sizeof(int),
301 		.mode		= 0644,
302 		.proc_handler	= &proc_dointvec_minmax,
303 		.extra1		= &one,
304 		.extra2		= &rwnd_scale_max,
305 	},
306 	{
307 		.procname	= "max_autoclose",
308 		.data		= &init_net.sctp.max_autoclose,
309 		.maxlen		= sizeof(unsigned long),
310 		.mode		= 0644,
311 		.proc_handler	= &proc_doulongvec_minmax,
312 		.extra1		= &max_autoclose_min,
313 		.extra2		= &max_autoclose_max,
314 	},
315 
316 	{ /* sentinel */ }
317 };
318 
319 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
320 				void __user *buffer, size_t *lenp,
321 				loff_t *ppos)
322 {
323 	struct net *net = current->nsproxy->net_ns;
324 	struct ctl_table tbl;
325 	bool changed = false;
326 	char *none = "none";
327 	char tmp[8];
328 	int ret;
329 
330 	memset(&tbl, 0, sizeof(struct ctl_table));
331 
332 	if (write) {
333 		tbl.data = tmp;
334 		tbl.maxlen = sizeof(tmp);
335 	} else {
336 		tbl.data = net->sctp.sctp_hmac_alg ? : none;
337 		tbl.maxlen = strlen(tbl.data);
338 	}
339 
340 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
341 	if (write && ret == 0) {
342 #ifdef CONFIG_CRYPTO_MD5
343 		if (!strncmp(tmp, "md5", 3)) {
344 			net->sctp.sctp_hmac_alg = "md5";
345 			changed = true;
346 		}
347 #endif
348 #ifdef CONFIG_CRYPTO_SHA1
349 		if (!strncmp(tmp, "sha1", 4)) {
350 			net->sctp.sctp_hmac_alg = "sha1";
351 			changed = true;
352 		}
353 #endif
354 		if (!strncmp(tmp, "none", 4)) {
355 			net->sctp.sctp_hmac_alg = NULL;
356 			changed = true;
357 		}
358 		if (!changed)
359 			ret = -EINVAL;
360 	}
361 
362 	return ret;
363 }
364 
365 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
366 				void __user *buffer, size_t *lenp,
367 				loff_t *ppos)
368 {
369 	struct net *net = current->nsproxy->net_ns;
370 	unsigned int min = *(unsigned int *) ctl->extra1;
371 	unsigned int max = *(unsigned int *) ctl->extra2;
372 	struct ctl_table tbl;
373 	int ret, new_value;
374 
375 	memset(&tbl, 0, sizeof(struct ctl_table));
376 	tbl.maxlen = sizeof(unsigned int);
377 
378 	if (write)
379 		tbl.data = &new_value;
380 	else
381 		tbl.data = &net->sctp.rto_min;
382 
383 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
384 	if (write && ret == 0) {
385 		if (new_value > max || new_value < min)
386 			return -EINVAL;
387 
388 		net->sctp.rto_min = new_value;
389 	}
390 
391 	return ret;
392 }
393 
394 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
395 				void __user *buffer, size_t *lenp,
396 				loff_t *ppos)
397 {
398 	struct net *net = current->nsproxy->net_ns;
399 	unsigned int min = *(unsigned int *) ctl->extra1;
400 	unsigned int max = *(unsigned int *) ctl->extra2;
401 	struct ctl_table tbl;
402 	int ret, new_value;
403 
404 	memset(&tbl, 0, sizeof(struct ctl_table));
405 	tbl.maxlen = sizeof(unsigned int);
406 
407 	if (write)
408 		tbl.data = &new_value;
409 	else
410 		tbl.data = &net->sctp.rto_max;
411 
412 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
413 	if (write && ret == 0) {
414 		if (new_value > max || new_value < min)
415 			return -EINVAL;
416 
417 		net->sctp.rto_max = new_value;
418 	}
419 
420 	return ret;
421 }
422 
423 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
424 				   void __user *buffer, size_t *lenp,
425 				   loff_t *ppos)
426 {
427 	if (write)
428 		pr_warn_once("Changing rto_alpha or rto_beta may lead to "
429 			     "suboptimal rtt/srtt estimations!\n");
430 
431 	return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
432 }
433 
434 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
435 			     void __user *buffer, size_t *lenp,
436 			     loff_t *ppos)
437 {
438 	struct net *net = current->nsproxy->net_ns;
439 	struct ctl_table tbl;
440 	int new_value, ret;
441 
442 	memset(&tbl, 0, sizeof(struct ctl_table));
443 	tbl.maxlen = sizeof(unsigned int);
444 
445 	if (write)
446 		tbl.data = &new_value;
447 	else
448 		tbl.data = &net->sctp.auth_enable;
449 
450 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
451 	if (write && ret == 0) {
452 		struct sock *sk = net->sctp.ctl_sock;
453 
454 		net->sctp.auth_enable = new_value;
455 		/* Update the value in the control socket */
456 		lock_sock(sk);
457 		sctp_sk(sk)->ep->auth_enable = new_value;
458 		release_sock(sk);
459 	}
460 
461 	return ret;
462 }
463 
464 int sctp_sysctl_net_register(struct net *net)
465 {
466 	struct ctl_table *table;
467 	int i;
468 
469 	table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
470 	if (!table)
471 		return -ENOMEM;
472 
473 	for (i = 0; table[i].data; i++)
474 		table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
475 
476 	net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
477 	if (net->sctp.sysctl_header == NULL) {
478 		kfree(table);
479 		return -ENOMEM;
480 	}
481 	return 0;
482 }
483 
484 void sctp_sysctl_net_unregister(struct net *net)
485 {
486 	struct ctl_table *table;
487 
488 	table = net->sctp.sysctl_header->ctl_table_arg;
489 	unregister_net_sysctl_table(net->sctp.sysctl_header);
490 	kfree(table);
491 }
492 
493 static struct ctl_table_header *sctp_sysctl_header;
494 
495 /* Sysctl registration.  */
496 void sctp_sysctl_register(void)
497 {
498 	sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
499 }
500 
501 /* Sysctl deregistration.  */
502 void sctp_sysctl_unregister(void)
503 {
504 	unregister_net_sysctl_table(sctp_sysctl_header);
505 }
506