xref: /openbmc/linux/net/sctp/sysctl.c (revision cee50c2a) 
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 static int pf_expose_max = SCTP_PF_EXPOSE_MAX;
38 static int ps_retrans_max = SCTP_PS_RETRANS_MAX;
39 
40 static unsigned long max_autoclose_min = 0;
41 static unsigned long max_autoclose_max =
42 	(MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
43 	? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
44 
45 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
46 				 void *buffer, size_t *lenp, loff_t *ppos);
47 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
48 				void *buffer, size_t *lenp, loff_t *ppos);
49 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write, void *buffer,
50 				size_t *lenp, loff_t *ppos);
51 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
52 				   void *buffer, size_t *lenp, loff_t *ppos);
53 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
54 			     void *buffer, size_t *lenp, loff_t *ppos);
55 
56 static struct ctl_table sctp_table[] = {
57 	{
58 		.procname	= "sctp_mem",
59 		.data		= &sysctl_sctp_mem,
60 		.maxlen		= sizeof(sysctl_sctp_mem),
61 		.mode		= 0644,
62 		.proc_handler	= proc_doulongvec_minmax
63 	},
64 	{
65 		.procname	= "sctp_rmem",
66 		.data		= &sysctl_sctp_rmem,
67 		.maxlen		= sizeof(sysctl_sctp_rmem),
68 		.mode		= 0644,
69 		.proc_handler	= proc_dointvec,
70 	},
71 	{
72 		.procname	= "sctp_wmem",
73 		.data		= &sysctl_sctp_wmem,
74 		.maxlen		= sizeof(sysctl_sctp_wmem),
75 		.mode		= 0644,
76 		.proc_handler	= proc_dointvec,
77 	},
78 
79 	{ /* sentinel */ }
80 };
81 
82 static struct ctl_table sctp_net_table[] = {
83 	{
84 		.procname	= "rto_initial",
85 		.data		= &init_net.sctp.rto_initial,
86 		.maxlen		= sizeof(unsigned int),
87 		.mode		= 0644,
88 		.proc_handler	= proc_dointvec_minmax,
89 		.extra1         = SYSCTL_ONE,
90 		.extra2         = &timer_max
91 	},
92 	{
93 		.procname	= "rto_min",
94 		.data		= &init_net.sctp.rto_min,
95 		.maxlen		= sizeof(unsigned int),
96 		.mode		= 0644,
97 		.proc_handler	= proc_sctp_do_rto_min,
98 		.extra1         = SYSCTL_ONE,
99 		.extra2         = &init_net.sctp.rto_max
100 	},
101 	{
102 		.procname	= "rto_max",
103 		.data		= &init_net.sctp.rto_max,
104 		.maxlen		= sizeof(unsigned int),
105 		.mode		= 0644,
106 		.proc_handler	= proc_sctp_do_rto_max,
107 		.extra1         = &init_net.sctp.rto_min,
108 		.extra2         = &timer_max
109 	},
110 	{
111 		.procname	= "rto_alpha_exp_divisor",
112 		.data		= &init_net.sctp.rto_alpha,
113 		.maxlen		= sizeof(int),
114 		.mode		= 0644,
115 		.proc_handler	= proc_sctp_do_alpha_beta,
116 		.extra1		= &rto_alpha_min,
117 		.extra2		= &rto_alpha_max,
118 	},
119 	{
120 		.procname	= "rto_beta_exp_divisor",
121 		.data		= &init_net.sctp.rto_beta,
122 		.maxlen		= sizeof(int),
123 		.mode		= 0644,
124 		.proc_handler	= proc_sctp_do_alpha_beta,
125 		.extra1		= &rto_beta_min,
126 		.extra2		= &rto_beta_max,
127 	},
128 	{
129 		.procname	= "max_burst",
130 		.data		= &init_net.sctp.max_burst,
131 		.maxlen		= sizeof(int),
132 		.mode		= 0644,
133 		.proc_handler	= proc_dointvec_minmax,
134 		.extra1		= SYSCTL_ZERO,
135 		.extra2		= SYSCTL_INT_MAX,
136 	},
137 	{
138 		.procname	= "cookie_preserve_enable",
139 		.data		= &init_net.sctp.cookie_preserve_enable,
140 		.maxlen		= sizeof(int),
141 		.mode		= 0644,
142 		.proc_handler	= proc_dointvec,
143 	},
144 	{
145 		.procname	= "cookie_hmac_alg",
146 		.data		= &init_net.sctp.sctp_hmac_alg,
147 		.maxlen		= 8,
148 		.mode		= 0644,
149 		.proc_handler	= proc_sctp_do_hmac_alg,
150 	},
151 	{
152 		.procname	= "valid_cookie_life",
153 		.data		= &init_net.sctp.valid_cookie_life,
154 		.maxlen		= sizeof(unsigned int),
155 		.mode		= 0644,
156 		.proc_handler	= proc_dointvec_minmax,
157 		.extra1         = SYSCTL_ONE,
158 		.extra2         = &timer_max
159 	},
160 	{
161 		.procname	= "sack_timeout",
162 		.data		= &init_net.sctp.sack_timeout,
163 		.maxlen		= sizeof(int),
164 		.mode		= 0644,
165 		.proc_handler	= proc_dointvec_minmax,
166 		.extra1         = &sack_timer_min,
167 		.extra2         = &sack_timer_max,
168 	},
169 	{
170 		.procname	= "hb_interval",
171 		.data		= &init_net.sctp.hb_interval,
172 		.maxlen		= sizeof(unsigned int),
173 		.mode		= 0644,
174 		.proc_handler	= proc_dointvec_minmax,
175 		.extra1         = SYSCTL_ONE,
176 		.extra2         = &timer_max
177 	},
178 	{
179 		.procname	= "association_max_retrans",
180 		.data		= &init_net.sctp.max_retrans_association,
181 		.maxlen		= sizeof(int),
182 		.mode		= 0644,
183 		.proc_handler	= proc_dointvec_minmax,
184 		.extra1		= SYSCTL_ONE,
185 		.extra2		= SYSCTL_INT_MAX,
186 	},
187 	{
188 		.procname	= "path_max_retrans",
189 		.data		= &init_net.sctp.max_retrans_path,
190 		.maxlen		= sizeof(int),
191 		.mode		= 0644,
192 		.proc_handler	= proc_dointvec_minmax,
193 		.extra1		= SYSCTL_ONE,
194 		.extra2		= SYSCTL_INT_MAX,
195 	},
196 	{
197 		.procname	= "max_init_retransmits",
198 		.data		= &init_net.sctp.max_retrans_init,
199 		.maxlen		= sizeof(int),
200 		.mode		= 0644,
201 		.proc_handler	= proc_dointvec_minmax,
202 		.extra1		= SYSCTL_ONE,
203 		.extra2		= SYSCTL_INT_MAX,
204 	},
205 	{
206 		.procname	= "pf_retrans",
207 		.data		= &init_net.sctp.pf_retrans,
208 		.maxlen		= sizeof(int),
209 		.mode		= 0644,
210 		.proc_handler	= proc_dointvec_minmax,
211 		.extra1		= SYSCTL_ZERO,
212 		.extra2		= &init_net.sctp.ps_retrans,
213 	},
214 	{
215 		.procname	= "ps_retrans",
216 		.data		= &init_net.sctp.ps_retrans,
217 		.maxlen		= sizeof(int),
218 		.mode		= 0644,
219 		.proc_handler	= proc_dointvec_minmax,
220 		.extra1		= &init_net.sctp.pf_retrans,
221 		.extra2		= &ps_retrans_max,
222 	},
223 	{
224 		.procname	= "sndbuf_policy",
225 		.data		= &init_net.sctp.sndbuf_policy,
226 		.maxlen		= sizeof(int),
227 		.mode		= 0644,
228 		.proc_handler	= proc_dointvec,
229 	},
230 	{
231 		.procname	= "rcvbuf_policy",
232 		.data		= &init_net.sctp.rcvbuf_policy,
233 		.maxlen		= sizeof(int),
234 		.mode		= 0644,
235 		.proc_handler	= proc_dointvec,
236 	},
237 	{
238 		.procname	= "default_auto_asconf",
239 		.data		= &init_net.sctp.default_auto_asconf,
240 		.maxlen		= sizeof(int),
241 		.mode		= 0644,
242 		.proc_handler	= proc_dointvec,
243 	},
244 	{
245 		.procname	= "addip_enable",
246 		.data		= &init_net.sctp.addip_enable,
247 		.maxlen		= sizeof(int),
248 		.mode		= 0644,
249 		.proc_handler	= proc_dointvec,
250 	},
251 	{
252 		.procname	= "addip_noauth_enable",
253 		.data		= &init_net.sctp.addip_noauth,
254 		.maxlen		= sizeof(int),
255 		.mode		= 0644,
256 		.proc_handler	= proc_dointvec,
257 	},
258 	{
259 		.procname	= "prsctp_enable",
260 		.data		= &init_net.sctp.prsctp_enable,
261 		.maxlen		= sizeof(int),
262 		.mode		= 0644,
263 		.proc_handler	= proc_dointvec,
264 	},
265 	{
266 		.procname	= "reconf_enable",
267 		.data		= &init_net.sctp.reconf_enable,
268 		.maxlen		= sizeof(int),
269 		.mode		= 0644,
270 		.proc_handler	= proc_dointvec,
271 	},
272 	{
273 		.procname	= "auth_enable",
274 		.data		= &init_net.sctp.auth_enable,
275 		.maxlen		= sizeof(int),
276 		.mode		= 0644,
277 		.proc_handler	= proc_sctp_do_auth,
278 	},
279 	{
280 		.procname	= "intl_enable",
281 		.data		= &init_net.sctp.intl_enable,
282 		.maxlen		= sizeof(int),
283 		.mode		= 0644,
284 		.proc_handler	= proc_dointvec,
285 	},
286 	{
287 		.procname	= "ecn_enable",
288 		.data		= &init_net.sctp.ecn_enable,
289 		.maxlen		= sizeof(int),
290 		.mode		= 0644,
291 		.proc_handler	= proc_dointvec,
292 	},
293 	{
294 		.procname	= "addr_scope_policy",
295 		.data		= &init_net.sctp.scope_policy,
296 		.maxlen		= sizeof(int),
297 		.mode		= 0644,
298 		.proc_handler	= proc_dointvec_minmax,
299 		.extra1		= SYSCTL_ZERO,
300 		.extra2		= &addr_scope_max,
301 	},
302 	{
303 		.procname	= "rwnd_update_shift",
304 		.data		= &init_net.sctp.rwnd_upd_shift,
305 		.maxlen		= sizeof(int),
306 		.mode		= 0644,
307 		.proc_handler	= &proc_dointvec_minmax,
308 		.extra1		= SYSCTL_ONE,
309 		.extra2		= &rwnd_scale_max,
310 	},
311 	{
312 		.procname	= "max_autoclose",
313 		.data		= &init_net.sctp.max_autoclose,
314 		.maxlen		= sizeof(unsigned long),
315 		.mode		= 0644,
316 		.proc_handler	= &proc_doulongvec_minmax,
317 		.extra1		= &max_autoclose_min,
318 		.extra2		= &max_autoclose_max,
319 	},
320 	{
321 		.procname	= "pf_enable",
322 		.data		= &init_net.sctp.pf_enable,
323 		.maxlen		= sizeof(int),
324 		.mode		= 0644,
325 		.proc_handler	= proc_dointvec,
326 	},
327 	{
328 		.procname	= "pf_expose",
329 		.data		= &init_net.sctp.pf_expose,
330 		.maxlen		= sizeof(int),
331 		.mode		= 0644,
332 		.proc_handler	= proc_dointvec_minmax,
333 		.extra1		= SYSCTL_ZERO,
334 		.extra2		= &pf_expose_max,
335 	},
336 
337 	{ /* sentinel */ }
338 };
339 
340 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
341 				 void *buffer, size_t *lenp, loff_t *ppos)
342 {
343 	struct net *net = current->nsproxy->net_ns;
344 	struct ctl_table tbl;
345 	bool changed = false;
346 	char *none = "none";
347 	char tmp[8] = {0};
348 	int ret;
349 
350 	memset(&tbl, 0, sizeof(struct ctl_table));
351 
352 	if (write) {
353 		tbl.data = tmp;
354 		tbl.maxlen = sizeof(tmp);
355 	} else {
356 		tbl.data = net->sctp.sctp_hmac_alg ? : none;
357 		tbl.maxlen = strlen(tbl.data);
358 	}
359 
360 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
361 	if (write && ret == 0) {
362 #ifdef CONFIG_CRYPTO_MD5
363 		if (!strncmp(tmp, "md5", 3)) {
364 			net->sctp.sctp_hmac_alg = "md5";
365 			changed = true;
366 		}
367 #endif
368 #ifdef CONFIG_CRYPTO_SHA1
369 		if (!strncmp(tmp, "sha1", 4)) {
370 			net->sctp.sctp_hmac_alg = "sha1";
371 			changed = true;
372 		}
373 #endif
374 		if (!strncmp(tmp, "none", 4)) {
375 			net->sctp.sctp_hmac_alg = NULL;
376 			changed = true;
377 		}
378 		if (!changed)
379 			ret = -EINVAL;
380 	}
381 
382 	return ret;
383 }
384 
385 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
386 				void *buffer, size_t *lenp, loff_t *ppos)
387 {
388 	struct net *net = current->nsproxy->net_ns;
389 	unsigned int min = *(unsigned int *) ctl->extra1;
390 	unsigned int max = *(unsigned int *) ctl->extra2;
391 	struct ctl_table tbl;
392 	int ret, new_value;
393 
394 	memset(&tbl, 0, sizeof(struct ctl_table));
395 	tbl.maxlen = sizeof(unsigned int);
396 
397 	if (write)
398 		tbl.data = &new_value;
399 	else
400 		tbl.data = &net->sctp.rto_min;
401 
402 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
403 	if (write && ret == 0) {
404 		if (new_value > max || new_value < min)
405 			return -EINVAL;
406 
407 		net->sctp.rto_min = new_value;
408 	}
409 
410 	return ret;
411 }
412 
413 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
414 				void *buffer, size_t *lenp, loff_t *ppos)
415 {
416 	struct net *net = current->nsproxy->net_ns;
417 	unsigned int min = *(unsigned int *) ctl->extra1;
418 	unsigned int max = *(unsigned int *) ctl->extra2;
419 	struct ctl_table tbl;
420 	int ret, new_value;
421 
422 	memset(&tbl, 0, sizeof(struct ctl_table));
423 	tbl.maxlen = sizeof(unsigned int);
424 
425 	if (write)
426 		tbl.data = &new_value;
427 	else
428 		tbl.data = &net->sctp.rto_max;
429 
430 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
431 	if (write && ret == 0) {
432 		if (new_value > max || new_value < min)
433 			return -EINVAL;
434 
435 		net->sctp.rto_max = new_value;
436 	}
437 
438 	return ret;
439 }
440 
441 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
442 				   void *buffer, size_t *lenp, loff_t *ppos)
443 {
444 	if (write)
445 		pr_warn_once("Changing rto_alpha or rto_beta may lead to "
446 			     "suboptimal rtt/srtt estimations!\n");
447 
448 	return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
449 }
450 
451 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
452 			     void *buffer, size_t *lenp, loff_t *ppos)
453 {
454 	struct net *net = current->nsproxy->net_ns;
455 	struct ctl_table tbl;
456 	int new_value, ret;
457 
458 	memset(&tbl, 0, sizeof(struct ctl_table));
459 	tbl.maxlen = sizeof(unsigned int);
460 
461 	if (write)
462 		tbl.data = &new_value;
463 	else
464 		tbl.data = &net->sctp.auth_enable;
465 
466 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
467 	if (write && ret == 0) {
468 		struct sock *sk = net->sctp.ctl_sock;
469 
470 		net->sctp.auth_enable = new_value;
471 		/* Update the value in the control socket */
472 		lock_sock(sk);
473 		sctp_sk(sk)->ep->auth_enable = new_value;
474 		release_sock(sk);
475 	}
476 
477 	return ret;
478 }
479 
480 int sctp_sysctl_net_register(struct net *net)
481 {
482 	struct ctl_table *table;
483 	int i;
484 
485 	table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
486 	if (!table)
487 		return -ENOMEM;
488 
489 	for (i = 0; table[i].data; i++)
490 		table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
491 
492 	net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
493 	if (net->sctp.sysctl_header == NULL) {
494 		kfree(table);
495 		return -ENOMEM;
496 	}
497 	return 0;
498 }
499 
500 void sctp_sysctl_net_unregister(struct net *net)
501 {
502 	struct ctl_table *table;
503 
504 	table = net->sctp.sysctl_header->ctl_table_arg;
505 	unregister_net_sysctl_table(net->sctp.sysctl_header);
506 	kfree(table);
507 }
508 
509 static struct ctl_table_header *sctp_sysctl_header;
510 
511 /* Sysctl registration.  */
512 void sctp_sysctl_register(void)
513 {
514 	sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
515 }
516 
517 /* Sysctl deregistration.  */
518 void sctp_sysctl_unregister(void)
519 {
520 	unregister_net_sysctl_table(sctp_sysctl_header);
521 }
522