xref: /linux/net/sctp/sysctl.c (revision eec4844f) 
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 timer_max = 86400000; /* ms in one day */
29 static int sack_timer_min = 1;
30 static int sack_timer_max = 500;
31 static int addr_scope_max = SCTP_SCOPE_POLICY_MAX;
32 static int rwnd_scale_max = 16;
33 static int rto_alpha_min = 0;
34 static int rto_beta_min = 0;
35 static int rto_alpha_max = 1000;
36 static int rto_beta_max = 1000;
37 
38 static unsigned long max_autoclose_min = 0;
39 static unsigned long max_autoclose_max =
40 	(MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
41 	? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
42 
43 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
44 				void __user *buffer, size_t *lenp,
45 				loff_t *ppos);
46 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
47 				void __user *buffer, size_t *lenp,
48 				loff_t *ppos);
49 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
50 				void __user *buffer, size_t *lenp,
51 				loff_t *ppos);
52 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
53 				   void __user *buffer, size_t *lenp,
54 				   loff_t *ppos);
55 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
56 			     void __user *buffer, size_t *lenp,
57 			     loff_t *ppos);
58 
59 static struct ctl_table sctp_table[] = {
60 	{
61 		.procname	= "sctp_mem",
62 		.data		= &sysctl_sctp_mem,
63 		.maxlen		= sizeof(sysctl_sctp_mem),
64 		.mode		= 0644,
65 		.proc_handler	= proc_doulongvec_minmax
66 	},
67 	{
68 		.procname	= "sctp_rmem",
69 		.data		= &sysctl_sctp_rmem,
70 		.maxlen		= sizeof(sysctl_sctp_rmem),
71 		.mode		= 0644,
72 		.proc_handler	= proc_dointvec,
73 	},
74 	{
75 		.procname	= "sctp_wmem",
76 		.data		= &sysctl_sctp_wmem,
77 		.maxlen		= sizeof(sysctl_sctp_wmem),
78 		.mode		= 0644,
79 		.proc_handler	= proc_dointvec,
80 	},
81 
82 	{ /* sentinel */ }
83 };
84 
85 static struct ctl_table sctp_net_table[] = {
86 	{
87 		.procname	= "rto_initial",
88 		.data		= &init_net.sctp.rto_initial,
89 		.maxlen		= sizeof(unsigned int),
90 		.mode		= 0644,
91 		.proc_handler	= proc_dointvec_minmax,
92 		.extra1         = SYSCTL_ONE,
93 		.extra2         = &timer_max
94 	},
95 	{
96 		.procname	= "rto_min",
97 		.data		= &init_net.sctp.rto_min,
98 		.maxlen		= sizeof(unsigned int),
99 		.mode		= 0644,
100 		.proc_handler	= proc_sctp_do_rto_min,
101 		.extra1         = SYSCTL_ONE,
102 		.extra2         = &init_net.sctp.rto_max
103 	},
104 	{
105 		.procname	= "rto_max",
106 		.data		= &init_net.sctp.rto_max,
107 		.maxlen		= sizeof(unsigned int),
108 		.mode		= 0644,
109 		.proc_handler	= proc_sctp_do_rto_max,
110 		.extra1         = &init_net.sctp.rto_min,
111 		.extra2         = &timer_max
112 	},
113 	{
114 		.procname	= "rto_alpha_exp_divisor",
115 		.data		= &init_net.sctp.rto_alpha,
116 		.maxlen		= sizeof(int),
117 		.mode		= 0644,
118 		.proc_handler	= proc_sctp_do_alpha_beta,
119 		.extra1		= &rto_alpha_min,
120 		.extra2		= &rto_alpha_max,
121 	},
122 	{
123 		.procname	= "rto_beta_exp_divisor",
124 		.data		= &init_net.sctp.rto_beta,
125 		.maxlen		= sizeof(int),
126 		.mode		= 0644,
127 		.proc_handler	= proc_sctp_do_alpha_beta,
128 		.extra1		= &rto_beta_min,
129 		.extra2		= &rto_beta_max,
130 	},
131 	{
132 		.procname	= "max_burst",
133 		.data		= &init_net.sctp.max_burst,
134 		.maxlen		= sizeof(int),
135 		.mode		= 0644,
136 		.proc_handler	= proc_dointvec_minmax,
137 		.extra1		= SYSCTL_ZERO,
138 		.extra2		= SYSCTL_INT_MAX,
139 	},
140 	{
141 		.procname	= "cookie_preserve_enable",
142 		.data		= &init_net.sctp.cookie_preserve_enable,
143 		.maxlen		= sizeof(int),
144 		.mode		= 0644,
145 		.proc_handler	= proc_dointvec,
146 	},
147 	{
148 		.procname	= "cookie_hmac_alg",
149 		.data		= &init_net.sctp.sctp_hmac_alg,
150 		.maxlen		= 8,
151 		.mode		= 0644,
152 		.proc_handler	= proc_sctp_do_hmac_alg,
153 	},
154 	{
155 		.procname	= "valid_cookie_life",
156 		.data		= &init_net.sctp.valid_cookie_life,
157 		.maxlen		= sizeof(unsigned int),
158 		.mode		= 0644,
159 		.proc_handler	= proc_dointvec_minmax,
160 		.extra1         = SYSCTL_ONE,
161 		.extra2         = &timer_max
162 	},
163 	{
164 		.procname	= "sack_timeout",
165 		.data		= &init_net.sctp.sack_timeout,
166 		.maxlen		= sizeof(int),
167 		.mode		= 0644,
168 		.proc_handler	= proc_dointvec_minmax,
169 		.extra1         = &sack_timer_min,
170 		.extra2         = &sack_timer_max,
171 	},
172 	{
173 		.procname	= "hb_interval",
174 		.data		= &init_net.sctp.hb_interval,
175 		.maxlen		= sizeof(unsigned int),
176 		.mode		= 0644,
177 		.proc_handler	= proc_dointvec_minmax,
178 		.extra1         = SYSCTL_ONE,
179 		.extra2         = &timer_max
180 	},
181 	{
182 		.procname	= "association_max_retrans",
183 		.data		= &init_net.sctp.max_retrans_association,
184 		.maxlen		= sizeof(int),
185 		.mode		= 0644,
186 		.proc_handler	= proc_dointvec_minmax,
187 		.extra1		= SYSCTL_ONE,
188 		.extra2		= SYSCTL_INT_MAX,
189 	},
190 	{
191 		.procname	= "path_max_retrans",
192 		.data		= &init_net.sctp.max_retrans_path,
193 		.maxlen		= sizeof(int),
194 		.mode		= 0644,
195 		.proc_handler	= proc_dointvec_minmax,
196 		.extra1		= SYSCTL_ONE,
197 		.extra2		= SYSCTL_INT_MAX,
198 	},
199 	{
200 		.procname	= "max_init_retransmits",
201 		.data		= &init_net.sctp.max_retrans_init,
202 		.maxlen		= sizeof(int),
203 		.mode		= 0644,
204 		.proc_handler	= proc_dointvec_minmax,
205 		.extra1		= SYSCTL_ONE,
206 		.extra2		= SYSCTL_INT_MAX,
207 	},
208 	{
209 		.procname	= "pf_retrans",
210 		.data		= &init_net.sctp.pf_retrans,
211 		.maxlen		= sizeof(int),
212 		.mode		= 0644,
213 		.proc_handler	= proc_dointvec_minmax,
214 		.extra1		= SYSCTL_ZERO,
215 		.extra2		= SYSCTL_INT_MAX,
216 	},
217 	{
218 		.procname	= "sndbuf_policy",
219 		.data		= &init_net.sctp.sndbuf_policy,
220 		.maxlen		= sizeof(int),
221 		.mode		= 0644,
222 		.proc_handler	= proc_dointvec,
223 	},
224 	{
225 		.procname	= "rcvbuf_policy",
226 		.data		= &init_net.sctp.rcvbuf_policy,
227 		.maxlen		= sizeof(int),
228 		.mode		= 0644,
229 		.proc_handler	= proc_dointvec,
230 	},
231 	{
232 		.procname	= "default_auto_asconf",
233 		.data		= &init_net.sctp.default_auto_asconf,
234 		.maxlen		= sizeof(int),
235 		.mode		= 0644,
236 		.proc_handler	= proc_dointvec,
237 	},
238 	{
239 		.procname	= "addip_enable",
240 		.data		= &init_net.sctp.addip_enable,
241 		.maxlen		= sizeof(int),
242 		.mode		= 0644,
243 		.proc_handler	= proc_dointvec,
244 	},
245 	{
246 		.procname	= "addip_noauth_enable",
247 		.data		= &init_net.sctp.addip_noauth,
248 		.maxlen		= sizeof(int),
249 		.mode		= 0644,
250 		.proc_handler	= proc_dointvec,
251 	},
252 	{
253 		.procname	= "prsctp_enable",
254 		.data		= &init_net.sctp.prsctp_enable,
255 		.maxlen		= sizeof(int),
256 		.mode		= 0644,
257 		.proc_handler	= proc_dointvec,
258 	},
259 	{
260 		.procname	= "reconf_enable",
261 		.data		= &init_net.sctp.reconf_enable,
262 		.maxlen		= sizeof(int),
263 		.mode		= 0644,
264 		.proc_handler	= proc_dointvec,
265 	},
266 	{
267 		.procname	= "auth_enable",
268 		.data		= &init_net.sctp.auth_enable,
269 		.maxlen		= sizeof(int),
270 		.mode		= 0644,
271 		.proc_handler	= proc_sctp_do_auth,
272 	},
273 	{
274 		.procname	= "intl_enable",
275 		.data		= &init_net.sctp.intl_enable,
276 		.maxlen		= sizeof(int),
277 		.mode		= 0644,
278 		.proc_handler	= proc_dointvec,
279 	},
280 	{
281 		.procname	= "addr_scope_policy",
282 		.data		= &init_net.sctp.scope_policy,
283 		.maxlen		= sizeof(int),
284 		.mode		= 0644,
285 		.proc_handler	= proc_dointvec_minmax,
286 		.extra1		= SYSCTL_ZERO,
287 		.extra2		= &addr_scope_max,
288 	},
289 	{
290 		.procname	= "rwnd_update_shift",
291 		.data		= &init_net.sctp.rwnd_upd_shift,
292 		.maxlen		= sizeof(int),
293 		.mode		= 0644,
294 		.proc_handler	= &proc_dointvec_minmax,
295 		.extra1		= SYSCTL_ONE,
296 		.extra2		= &rwnd_scale_max,
297 	},
298 	{
299 		.procname	= "max_autoclose",
300 		.data		= &init_net.sctp.max_autoclose,
301 		.maxlen		= sizeof(unsigned long),
302 		.mode		= 0644,
303 		.proc_handler	= &proc_doulongvec_minmax,
304 		.extra1		= &max_autoclose_min,
305 		.extra2		= &max_autoclose_max,
306 	},
307 	{
308 		.procname	= "pf_enable",
309 		.data		= &init_net.sctp.pf_enable,
310 		.maxlen		= sizeof(int),
311 		.mode		= 0644,
312 		.proc_handler	= proc_dointvec,
313 	},
314 
315 	{ /* sentinel */ }
316 };
317 
318 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
319 				void __user *buffer, size_t *lenp,
320 				loff_t *ppos)
321 {
322 	struct net *net = current->nsproxy->net_ns;
323 	struct ctl_table tbl;
324 	bool changed = false;
325 	char *none = "none";
326 	char tmp[8] = {0};
327 	int ret;
328 
329 	memset(&tbl, 0, sizeof(struct ctl_table));
330 
331 	if (write) {
332 		tbl.data = tmp;
333 		tbl.maxlen = sizeof(tmp);
334 	} else {
335 		tbl.data = net->sctp.sctp_hmac_alg ? : none;
336 		tbl.maxlen = strlen(tbl.data);
337 	}
338 
339 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
340 	if (write && ret == 0) {
341 #ifdef CONFIG_CRYPTO_MD5
342 		if (!strncmp(tmp, "md5", 3)) {
343 			net->sctp.sctp_hmac_alg = "md5";
344 			changed = true;
345 		}
346 #endif
347 #ifdef CONFIG_CRYPTO_SHA1
348 		if (!strncmp(tmp, "sha1", 4)) {
349 			net->sctp.sctp_hmac_alg = "sha1";
350 			changed = true;
351 		}
352 #endif
353 		if (!strncmp(tmp, "none", 4)) {
354 			net->sctp.sctp_hmac_alg = NULL;
355 			changed = true;
356 		}
357 		if (!changed)
358 			ret = -EINVAL;
359 	}
360 
361 	return ret;
362 }
363 
364 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
365 				void __user *buffer, size_t *lenp,
366 				loff_t *ppos)
367 {
368 	struct net *net = current->nsproxy->net_ns;
369 	unsigned int min = *(unsigned int *) ctl->extra1;
370 	unsigned int max = *(unsigned int *) ctl->extra2;
371 	struct ctl_table tbl;
372 	int ret, new_value;
373 
374 	memset(&tbl, 0, sizeof(struct ctl_table));
375 	tbl.maxlen = sizeof(unsigned int);
376 
377 	if (write)
378 		tbl.data = &new_value;
379 	else
380 		tbl.data = &net->sctp.rto_min;
381 
382 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
383 	if (write && ret == 0) {
384 		if (new_value > max || new_value < min)
385 			return -EINVAL;
386 
387 		net->sctp.rto_min = new_value;
388 	}
389 
390 	return ret;
391 }
392 
393 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
394 				void __user *buffer, size_t *lenp,
395 				loff_t *ppos)
396 {
397 	struct net *net = current->nsproxy->net_ns;
398 	unsigned int min = *(unsigned int *) ctl->extra1;
399 	unsigned int max = *(unsigned int *) ctl->extra2;
400 	struct ctl_table tbl;
401 	int ret, new_value;
402 
403 	memset(&tbl, 0, sizeof(struct ctl_table));
404 	tbl.maxlen = sizeof(unsigned int);
405 
406 	if (write)
407 		tbl.data = &new_value;
408 	else
409 		tbl.data = &net->sctp.rto_max;
410 
411 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
412 	if (write && ret == 0) {
413 		if (new_value > max || new_value < min)
414 			return -EINVAL;
415 
416 		net->sctp.rto_max = new_value;
417 	}
418 
419 	return ret;
420 }
421 
422 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
423 				   void __user *buffer, size_t *lenp,
424 				   loff_t *ppos)
425 {
426 	if (write)
427 		pr_warn_once("Changing rto_alpha or rto_beta may lead to "
428 			     "suboptimal rtt/srtt estimations!\n");
429 
430 	return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
431 }
432 
433 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
434 			     void __user *buffer, size_t *lenp,
435 			     loff_t *ppos)
436 {
437 	struct net *net = current->nsproxy->net_ns;
438 	struct ctl_table tbl;
439 	int new_value, ret;
440 
441 	memset(&tbl, 0, sizeof(struct ctl_table));
442 	tbl.maxlen = sizeof(unsigned int);
443 
444 	if (write)
445 		tbl.data = &new_value;
446 	else
447 		tbl.data = &net->sctp.auth_enable;
448 
449 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
450 	if (write && ret == 0) {
451 		struct sock *sk = net->sctp.ctl_sock;
452 
453 		net->sctp.auth_enable = new_value;
454 		/* Update the value in the control socket */
455 		lock_sock(sk);
456 		sctp_sk(sk)->ep->auth_enable = new_value;
457 		release_sock(sk);
458 	}
459 
460 	return ret;
461 }
462 
463 int sctp_sysctl_net_register(struct net *net)
464 {
465 	struct ctl_table *table;
466 	int i;
467 
468 	table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
469 	if (!table)
470 		return -ENOMEM;
471 
472 	for (i = 0; table[i].data; i++)
473 		table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
474 
475 	net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
476 	if (net->sctp.sysctl_header == NULL) {
477 		kfree(table);
478 		return -ENOMEM;
479 	}
480 	return 0;
481 }
482 
483 void sctp_sysctl_net_unregister(struct net *net)
484 {
485 	struct ctl_table *table;
486 
487 	table = net->sctp.sysctl_header->ctl_table_arg;
488 	unregister_net_sysctl_table(net->sctp.sysctl_header);
489 	kfree(table);
490 }
491 
492 static struct ctl_table_header *sctp_sysctl_header;
493 
494 /* Sysctl registration.  */
495 void sctp_sysctl_register(void)
496 {
497 	sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
498 }
499 
500 /* Sysctl deregistration.  */
501 void sctp_sysctl_unregister(void)
502 {
503 	unregister_net_sysctl_table(sctp_sysctl_header);
504 }
505