xref: /linux/net/sctp/sysctl.c (revision 44f57d78) 
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 zero = 0;
29 static int one = 1;
30 static int timer_max = 86400000; /* ms in one day */
31 static int int_max = INT_MAX;
32 static int sack_timer_min = 1;
33 static int sack_timer_max = 500;
34 static int addr_scope_max = SCTP_SCOPE_POLICY_MAX;
35 static int rwnd_scale_max = 16;
36 static int rto_alpha_min = 0;
37 static int rto_beta_min = 0;
38 static int rto_alpha_max = 1000;
39 static int rto_beta_max = 1000;
40 
41 static unsigned long max_autoclose_min = 0;
42 static unsigned long max_autoclose_max =
43 	(MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
44 	? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
45 
46 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
47 				void __user *buffer, size_t *lenp,
48 				loff_t *ppos);
49 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
50 				void __user *buffer, size_t *lenp,
51 				loff_t *ppos);
52 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
53 				void __user *buffer, size_t *lenp,
54 				loff_t *ppos);
55 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
56 				   void __user *buffer, size_t *lenp,
57 				   loff_t *ppos);
58 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
59 			     void __user *buffer, size_t *lenp,
60 			     loff_t *ppos);
61 
62 static struct ctl_table sctp_table[] = {
63 	{
64 		.procname	= "sctp_mem",
65 		.data		= &sysctl_sctp_mem,
66 		.maxlen		= sizeof(sysctl_sctp_mem),
67 		.mode		= 0644,
68 		.proc_handler	= proc_doulongvec_minmax
69 	},
70 	{
71 		.procname	= "sctp_rmem",
72 		.data		= &sysctl_sctp_rmem,
73 		.maxlen		= sizeof(sysctl_sctp_rmem),
74 		.mode		= 0644,
75 		.proc_handler	= proc_dointvec,
76 	},
77 	{
78 		.procname	= "sctp_wmem",
79 		.data		= &sysctl_sctp_wmem,
80 		.maxlen		= sizeof(sysctl_sctp_wmem),
81 		.mode		= 0644,
82 		.proc_handler	= proc_dointvec,
83 	},
84 
85 	{ /* sentinel */ }
86 };
87 
88 static struct ctl_table sctp_net_table[] = {
89 	{
90 		.procname	= "rto_initial",
91 		.data		= &init_net.sctp.rto_initial,
92 		.maxlen		= sizeof(unsigned int),
93 		.mode		= 0644,
94 		.proc_handler	= proc_dointvec_minmax,
95 		.extra1         = &one,
96 		.extra2         = &timer_max
97 	},
98 	{
99 		.procname	= "rto_min",
100 		.data		= &init_net.sctp.rto_min,
101 		.maxlen		= sizeof(unsigned int),
102 		.mode		= 0644,
103 		.proc_handler	= proc_sctp_do_rto_min,
104 		.extra1         = &one,
105 		.extra2         = &init_net.sctp.rto_max
106 	},
107 	{
108 		.procname	= "rto_max",
109 		.data		= &init_net.sctp.rto_max,
110 		.maxlen		= sizeof(unsigned int),
111 		.mode		= 0644,
112 		.proc_handler	= proc_sctp_do_rto_max,
113 		.extra1         = &init_net.sctp.rto_min,
114 		.extra2         = &timer_max
115 	},
116 	{
117 		.procname	= "rto_alpha_exp_divisor",
118 		.data		= &init_net.sctp.rto_alpha,
119 		.maxlen		= sizeof(int),
120 		.mode		= 0644,
121 		.proc_handler	= proc_sctp_do_alpha_beta,
122 		.extra1		= &rto_alpha_min,
123 		.extra2		= &rto_alpha_max,
124 	},
125 	{
126 		.procname	= "rto_beta_exp_divisor",
127 		.data		= &init_net.sctp.rto_beta,
128 		.maxlen		= sizeof(int),
129 		.mode		= 0644,
130 		.proc_handler	= proc_sctp_do_alpha_beta,
131 		.extra1		= &rto_beta_min,
132 		.extra2		= &rto_beta_max,
133 	},
134 	{
135 		.procname	= "max_burst",
136 		.data		= &init_net.sctp.max_burst,
137 		.maxlen		= sizeof(int),
138 		.mode		= 0644,
139 		.proc_handler	= proc_dointvec_minmax,
140 		.extra1		= &zero,
141 		.extra2		= &int_max
142 	},
143 	{
144 		.procname	= "cookie_preserve_enable",
145 		.data		= &init_net.sctp.cookie_preserve_enable,
146 		.maxlen		= sizeof(int),
147 		.mode		= 0644,
148 		.proc_handler	= proc_dointvec,
149 	},
150 	{
151 		.procname	= "cookie_hmac_alg",
152 		.data		= &init_net.sctp.sctp_hmac_alg,
153 		.maxlen		= 8,
154 		.mode		= 0644,
155 		.proc_handler	= proc_sctp_do_hmac_alg,
156 	},
157 	{
158 		.procname	= "valid_cookie_life",
159 		.data		= &init_net.sctp.valid_cookie_life,
160 		.maxlen		= sizeof(unsigned int),
161 		.mode		= 0644,
162 		.proc_handler	= proc_dointvec_minmax,
163 		.extra1         = &one,
164 		.extra2         = &timer_max
165 	},
166 	{
167 		.procname	= "sack_timeout",
168 		.data		= &init_net.sctp.sack_timeout,
169 		.maxlen		= sizeof(int),
170 		.mode		= 0644,
171 		.proc_handler	= proc_dointvec_minmax,
172 		.extra1         = &sack_timer_min,
173 		.extra2         = &sack_timer_max,
174 	},
175 	{
176 		.procname	= "hb_interval",
177 		.data		= &init_net.sctp.hb_interval,
178 		.maxlen		= sizeof(unsigned int),
179 		.mode		= 0644,
180 		.proc_handler	= proc_dointvec_minmax,
181 		.extra1         = &one,
182 		.extra2         = &timer_max
183 	},
184 	{
185 		.procname	= "association_max_retrans",
186 		.data		= &init_net.sctp.max_retrans_association,
187 		.maxlen		= sizeof(int),
188 		.mode		= 0644,
189 		.proc_handler	= proc_dointvec_minmax,
190 		.extra1		= &one,
191 		.extra2		= &int_max
192 	},
193 	{
194 		.procname	= "path_max_retrans",
195 		.data		= &init_net.sctp.max_retrans_path,
196 		.maxlen		= sizeof(int),
197 		.mode		= 0644,
198 		.proc_handler	= proc_dointvec_minmax,
199 		.extra1		= &one,
200 		.extra2		= &int_max
201 	},
202 	{
203 		.procname	= "max_init_retransmits",
204 		.data		= &init_net.sctp.max_retrans_init,
205 		.maxlen		= sizeof(int),
206 		.mode		= 0644,
207 		.proc_handler	= proc_dointvec_minmax,
208 		.extra1		= &one,
209 		.extra2		= &int_max
210 	},
211 	{
212 		.procname	= "pf_retrans",
213 		.data		= &init_net.sctp.pf_retrans,
214 		.maxlen		= sizeof(int),
215 		.mode		= 0644,
216 		.proc_handler	= proc_dointvec_minmax,
217 		.extra1		= &zero,
218 		.extra2		= &int_max
219 	},
220 	{
221 		.procname	= "sndbuf_policy",
222 		.data		= &init_net.sctp.sndbuf_policy,
223 		.maxlen		= sizeof(int),
224 		.mode		= 0644,
225 		.proc_handler	= proc_dointvec,
226 	},
227 	{
228 		.procname	= "rcvbuf_policy",
229 		.data		= &init_net.sctp.rcvbuf_policy,
230 		.maxlen		= sizeof(int),
231 		.mode		= 0644,
232 		.proc_handler	= proc_dointvec,
233 	},
234 	{
235 		.procname	= "default_auto_asconf",
236 		.data		= &init_net.sctp.default_auto_asconf,
237 		.maxlen		= sizeof(int),
238 		.mode		= 0644,
239 		.proc_handler	= proc_dointvec,
240 	},
241 	{
242 		.procname	= "addip_enable",
243 		.data		= &init_net.sctp.addip_enable,
244 		.maxlen		= sizeof(int),
245 		.mode		= 0644,
246 		.proc_handler	= proc_dointvec,
247 	},
248 	{
249 		.procname	= "addip_noauth_enable",
250 		.data		= &init_net.sctp.addip_noauth,
251 		.maxlen		= sizeof(int),
252 		.mode		= 0644,
253 		.proc_handler	= proc_dointvec,
254 	},
255 	{
256 		.procname	= "prsctp_enable",
257 		.data		= &init_net.sctp.prsctp_enable,
258 		.maxlen		= sizeof(int),
259 		.mode		= 0644,
260 		.proc_handler	= proc_dointvec,
261 	},
262 	{
263 		.procname	= "reconf_enable",
264 		.data		= &init_net.sctp.reconf_enable,
265 		.maxlen		= sizeof(int),
266 		.mode		= 0644,
267 		.proc_handler	= proc_dointvec,
268 	},
269 	{
270 		.procname	= "auth_enable",
271 		.data		= &init_net.sctp.auth_enable,
272 		.maxlen		= sizeof(int),
273 		.mode		= 0644,
274 		.proc_handler	= proc_sctp_do_auth,
275 	},
276 	{
277 		.procname	= "intl_enable",
278 		.data		= &init_net.sctp.intl_enable,
279 		.maxlen		= sizeof(int),
280 		.mode		= 0644,
281 		.proc_handler	= proc_dointvec,
282 	},
283 	{
284 		.procname	= "addr_scope_policy",
285 		.data		= &init_net.sctp.scope_policy,
286 		.maxlen		= sizeof(int),
287 		.mode		= 0644,
288 		.proc_handler	= proc_dointvec_minmax,
289 		.extra1		= &zero,
290 		.extra2		= &addr_scope_max,
291 	},
292 	{
293 		.procname	= "rwnd_update_shift",
294 		.data		= &init_net.sctp.rwnd_upd_shift,
295 		.maxlen		= sizeof(int),
296 		.mode		= 0644,
297 		.proc_handler	= &proc_dointvec_minmax,
298 		.extra1		= &one,
299 		.extra2		= &rwnd_scale_max,
300 	},
301 	{
302 		.procname	= "max_autoclose",
303 		.data		= &init_net.sctp.max_autoclose,
304 		.maxlen		= sizeof(unsigned long),
305 		.mode		= 0644,
306 		.proc_handler	= &proc_doulongvec_minmax,
307 		.extra1		= &max_autoclose_min,
308 		.extra2		= &max_autoclose_max,
309 	},
310 	{
311 		.procname	= "pf_enable",
312 		.data		= &init_net.sctp.pf_enable,
313 		.maxlen		= sizeof(int),
314 		.mode		= 0644,
315 		.proc_handler	= proc_dointvec,
316 	},
317 
318 	{ /* sentinel */ }
319 };
320 
321 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
322 				void __user *buffer, size_t *lenp,
323 				loff_t *ppos)
324 {
325 	struct net *net = current->nsproxy->net_ns;
326 	struct ctl_table tbl;
327 	bool changed = false;
328 	char *none = "none";
329 	char tmp[8] = {0};
330 	int ret;
331 
332 	memset(&tbl, 0, sizeof(struct ctl_table));
333 
334 	if (write) {
335 		tbl.data = tmp;
336 		tbl.maxlen = sizeof(tmp);
337 	} else {
338 		tbl.data = net->sctp.sctp_hmac_alg ? : none;
339 		tbl.maxlen = strlen(tbl.data);
340 	}
341 
342 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
343 	if (write && ret == 0) {
344 #ifdef CONFIG_CRYPTO_MD5
345 		if (!strncmp(tmp, "md5", 3)) {
346 			net->sctp.sctp_hmac_alg = "md5";
347 			changed = true;
348 		}
349 #endif
350 #ifdef CONFIG_CRYPTO_SHA1
351 		if (!strncmp(tmp, "sha1", 4)) {
352 			net->sctp.sctp_hmac_alg = "sha1";
353 			changed = true;
354 		}
355 #endif
356 		if (!strncmp(tmp, "none", 4)) {
357 			net->sctp.sctp_hmac_alg = NULL;
358 			changed = true;
359 		}
360 		if (!changed)
361 			ret = -EINVAL;
362 	}
363 
364 	return ret;
365 }
366 
367 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
368 				void __user *buffer, size_t *lenp,
369 				loff_t *ppos)
370 {
371 	struct net *net = current->nsproxy->net_ns;
372 	unsigned int min = *(unsigned int *) ctl->extra1;
373 	unsigned int max = *(unsigned int *) ctl->extra2;
374 	struct ctl_table tbl;
375 	int ret, new_value;
376 
377 	memset(&tbl, 0, sizeof(struct ctl_table));
378 	tbl.maxlen = sizeof(unsigned int);
379 
380 	if (write)
381 		tbl.data = &new_value;
382 	else
383 		tbl.data = &net->sctp.rto_min;
384 
385 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
386 	if (write && ret == 0) {
387 		if (new_value > max || new_value < min)
388 			return -EINVAL;
389 
390 		net->sctp.rto_min = new_value;
391 	}
392 
393 	return ret;
394 }
395 
396 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
397 				void __user *buffer, size_t *lenp,
398 				loff_t *ppos)
399 {
400 	struct net *net = current->nsproxy->net_ns;
401 	unsigned int min = *(unsigned int *) ctl->extra1;
402 	unsigned int max = *(unsigned int *) ctl->extra2;
403 	struct ctl_table tbl;
404 	int ret, new_value;
405 
406 	memset(&tbl, 0, sizeof(struct ctl_table));
407 	tbl.maxlen = sizeof(unsigned int);
408 
409 	if (write)
410 		tbl.data = &new_value;
411 	else
412 		tbl.data = &net->sctp.rto_max;
413 
414 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
415 	if (write && ret == 0) {
416 		if (new_value > max || new_value < min)
417 			return -EINVAL;
418 
419 		net->sctp.rto_max = new_value;
420 	}
421 
422 	return ret;
423 }
424 
425 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
426 				   void __user *buffer, size_t *lenp,
427 				   loff_t *ppos)
428 {
429 	if (write)
430 		pr_warn_once("Changing rto_alpha or rto_beta may lead to "
431 			     "suboptimal rtt/srtt estimations!\n");
432 
433 	return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
434 }
435 
436 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
437 			     void __user *buffer, size_t *lenp,
438 			     loff_t *ppos)
439 {
440 	struct net *net = current->nsproxy->net_ns;
441 	struct ctl_table tbl;
442 	int new_value, ret;
443 
444 	memset(&tbl, 0, sizeof(struct ctl_table));
445 	tbl.maxlen = sizeof(unsigned int);
446 
447 	if (write)
448 		tbl.data = &new_value;
449 	else
450 		tbl.data = &net->sctp.auth_enable;
451 
452 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
453 	if (write && ret == 0) {
454 		struct sock *sk = net->sctp.ctl_sock;
455 
456 		net->sctp.auth_enable = new_value;
457 		/* Update the value in the control socket */
458 		lock_sock(sk);
459 		sctp_sk(sk)->ep->auth_enable = new_value;
460 		release_sock(sk);
461 	}
462 
463 	return ret;
464 }
465 
466 int sctp_sysctl_net_register(struct net *net)
467 {
468 	struct ctl_table *table;
469 	int i;
470 
471 	table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
472 	if (!table)
473 		return -ENOMEM;
474 
475 	for (i = 0; table[i].data; i++)
476 		table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
477 
478 	net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
479 	if (net->sctp.sysctl_header == NULL) {
480 		kfree(table);
481 		return -ENOMEM;
482 	}
483 	return 0;
484 }
485 
486 void sctp_sysctl_net_unregister(struct net *net)
487 {
488 	struct ctl_table *table;
489 
490 	table = net->sctp.sysctl_header->ctl_table_arg;
491 	unregister_net_sysctl_table(net->sctp.sysctl_header);
492 	kfree(table);
493 }
494 
495 static struct ctl_table_header *sctp_sysctl_header;
496 
497 /* Sysctl registration.  */
498 void sctp_sysctl_register(void)
499 {
500 	sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
501 }
502 
503 /* Sysctl deregistration.  */
504 void sctp_sysctl_unregister(void)
505 {
506 	unregister_net_sysctl_table(sctp_sysctl_header);
507 }
508