xref: /openbmc/linux/net/sctp/sysctl.c (revision e1cd7b80)
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 __user *buffer, size_t *lenp,
47 				loff_t *ppos);
48 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
49 				void __user *buffer, size_t *lenp,
50 				loff_t *ppos);
51 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
52 				void __user *buffer, size_t *lenp,
53 				loff_t *ppos);
54 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
55 				   void __user *buffer, size_t *lenp,
56 				   loff_t *ppos);
57 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
58 			     void __user *buffer, size_t *lenp,
59 			     loff_t *ppos);
60 
61 static struct ctl_table sctp_table[] = {
62 	{
63 		.procname	= "sctp_mem",
64 		.data		= &sysctl_sctp_mem,
65 		.maxlen		= sizeof(sysctl_sctp_mem),
66 		.mode		= 0644,
67 		.proc_handler	= proc_doulongvec_minmax
68 	},
69 	{
70 		.procname	= "sctp_rmem",
71 		.data		= &sysctl_sctp_rmem,
72 		.maxlen		= sizeof(sysctl_sctp_rmem),
73 		.mode		= 0644,
74 		.proc_handler	= proc_dointvec,
75 	},
76 	{
77 		.procname	= "sctp_wmem",
78 		.data		= &sysctl_sctp_wmem,
79 		.maxlen		= sizeof(sysctl_sctp_wmem),
80 		.mode		= 0644,
81 		.proc_handler	= proc_dointvec,
82 	},
83 
84 	{ /* sentinel */ }
85 };
86 
87 static struct ctl_table sctp_net_table[] = {
88 	{
89 		.procname	= "rto_initial",
90 		.data		= &init_net.sctp.rto_initial,
91 		.maxlen		= sizeof(unsigned int),
92 		.mode		= 0644,
93 		.proc_handler	= proc_dointvec_minmax,
94 		.extra1         = SYSCTL_ONE,
95 		.extra2         = &timer_max
96 	},
97 	{
98 		.procname	= "rto_min",
99 		.data		= &init_net.sctp.rto_min,
100 		.maxlen		= sizeof(unsigned int),
101 		.mode		= 0644,
102 		.proc_handler	= proc_sctp_do_rto_min,
103 		.extra1         = SYSCTL_ONE,
104 		.extra2         = &init_net.sctp.rto_max
105 	},
106 	{
107 		.procname	= "rto_max",
108 		.data		= &init_net.sctp.rto_max,
109 		.maxlen		= sizeof(unsigned int),
110 		.mode		= 0644,
111 		.proc_handler	= proc_sctp_do_rto_max,
112 		.extra1         = &init_net.sctp.rto_min,
113 		.extra2         = &timer_max
114 	},
115 	{
116 		.procname	= "rto_alpha_exp_divisor",
117 		.data		= &init_net.sctp.rto_alpha,
118 		.maxlen		= sizeof(int),
119 		.mode		= 0644,
120 		.proc_handler	= proc_sctp_do_alpha_beta,
121 		.extra1		= &rto_alpha_min,
122 		.extra2		= &rto_alpha_max,
123 	},
124 	{
125 		.procname	= "rto_beta_exp_divisor",
126 		.data		= &init_net.sctp.rto_beta,
127 		.maxlen		= sizeof(int),
128 		.mode		= 0644,
129 		.proc_handler	= proc_sctp_do_alpha_beta,
130 		.extra1		= &rto_beta_min,
131 		.extra2		= &rto_beta_max,
132 	},
133 	{
134 		.procname	= "max_burst",
135 		.data		= &init_net.sctp.max_burst,
136 		.maxlen		= sizeof(int),
137 		.mode		= 0644,
138 		.proc_handler	= proc_dointvec_minmax,
139 		.extra1		= SYSCTL_ZERO,
140 		.extra2		= SYSCTL_INT_MAX,
141 	},
142 	{
143 		.procname	= "cookie_preserve_enable",
144 		.data		= &init_net.sctp.cookie_preserve_enable,
145 		.maxlen		= sizeof(int),
146 		.mode		= 0644,
147 		.proc_handler	= proc_dointvec,
148 	},
149 	{
150 		.procname	= "cookie_hmac_alg",
151 		.data		= &init_net.sctp.sctp_hmac_alg,
152 		.maxlen		= 8,
153 		.mode		= 0644,
154 		.proc_handler	= proc_sctp_do_hmac_alg,
155 	},
156 	{
157 		.procname	= "valid_cookie_life",
158 		.data		= &init_net.sctp.valid_cookie_life,
159 		.maxlen		= sizeof(unsigned int),
160 		.mode		= 0644,
161 		.proc_handler	= proc_dointvec_minmax,
162 		.extra1         = SYSCTL_ONE,
163 		.extra2         = &timer_max
164 	},
165 	{
166 		.procname	= "sack_timeout",
167 		.data		= &init_net.sctp.sack_timeout,
168 		.maxlen		= sizeof(int),
169 		.mode		= 0644,
170 		.proc_handler	= proc_dointvec_minmax,
171 		.extra1         = &sack_timer_min,
172 		.extra2         = &sack_timer_max,
173 	},
174 	{
175 		.procname	= "hb_interval",
176 		.data		= &init_net.sctp.hb_interval,
177 		.maxlen		= sizeof(unsigned int),
178 		.mode		= 0644,
179 		.proc_handler	= proc_dointvec_minmax,
180 		.extra1         = SYSCTL_ONE,
181 		.extra2         = &timer_max
182 	},
183 	{
184 		.procname	= "association_max_retrans",
185 		.data		= &init_net.sctp.max_retrans_association,
186 		.maxlen		= sizeof(int),
187 		.mode		= 0644,
188 		.proc_handler	= proc_dointvec_minmax,
189 		.extra1		= SYSCTL_ONE,
190 		.extra2		= SYSCTL_INT_MAX,
191 	},
192 	{
193 		.procname	= "path_max_retrans",
194 		.data		= &init_net.sctp.max_retrans_path,
195 		.maxlen		= sizeof(int),
196 		.mode		= 0644,
197 		.proc_handler	= proc_dointvec_minmax,
198 		.extra1		= SYSCTL_ONE,
199 		.extra2		= SYSCTL_INT_MAX,
200 	},
201 	{
202 		.procname	= "max_init_retransmits",
203 		.data		= &init_net.sctp.max_retrans_init,
204 		.maxlen		= sizeof(int),
205 		.mode		= 0644,
206 		.proc_handler	= proc_dointvec_minmax,
207 		.extra1		= SYSCTL_ONE,
208 		.extra2		= SYSCTL_INT_MAX,
209 	},
210 	{
211 		.procname	= "pf_retrans",
212 		.data		= &init_net.sctp.pf_retrans,
213 		.maxlen		= sizeof(int),
214 		.mode		= 0644,
215 		.proc_handler	= proc_dointvec_minmax,
216 		.extra1		= SYSCTL_ZERO,
217 		.extra2		= &init_net.sctp.ps_retrans,
218 	},
219 	{
220 		.procname	= "ps_retrans",
221 		.data		= &init_net.sctp.ps_retrans,
222 		.maxlen		= sizeof(int),
223 		.mode		= 0644,
224 		.proc_handler	= proc_dointvec_minmax,
225 		.extra1		= &init_net.sctp.pf_retrans,
226 		.extra2		= &ps_retrans_max,
227 	},
228 	{
229 		.procname	= "sndbuf_policy",
230 		.data		= &init_net.sctp.sndbuf_policy,
231 		.maxlen		= sizeof(int),
232 		.mode		= 0644,
233 		.proc_handler	= proc_dointvec,
234 	},
235 	{
236 		.procname	= "rcvbuf_policy",
237 		.data		= &init_net.sctp.rcvbuf_policy,
238 		.maxlen		= sizeof(int),
239 		.mode		= 0644,
240 		.proc_handler	= proc_dointvec,
241 	},
242 	{
243 		.procname	= "default_auto_asconf",
244 		.data		= &init_net.sctp.default_auto_asconf,
245 		.maxlen		= sizeof(int),
246 		.mode		= 0644,
247 		.proc_handler	= proc_dointvec,
248 	},
249 	{
250 		.procname	= "addip_enable",
251 		.data		= &init_net.sctp.addip_enable,
252 		.maxlen		= sizeof(int),
253 		.mode		= 0644,
254 		.proc_handler	= proc_dointvec,
255 	},
256 	{
257 		.procname	= "addip_noauth_enable",
258 		.data		= &init_net.sctp.addip_noauth,
259 		.maxlen		= sizeof(int),
260 		.mode		= 0644,
261 		.proc_handler	= proc_dointvec,
262 	},
263 	{
264 		.procname	= "prsctp_enable",
265 		.data		= &init_net.sctp.prsctp_enable,
266 		.maxlen		= sizeof(int),
267 		.mode		= 0644,
268 		.proc_handler	= proc_dointvec,
269 	},
270 	{
271 		.procname	= "reconf_enable",
272 		.data		= &init_net.sctp.reconf_enable,
273 		.maxlen		= sizeof(int),
274 		.mode		= 0644,
275 		.proc_handler	= proc_dointvec,
276 	},
277 	{
278 		.procname	= "auth_enable",
279 		.data		= &init_net.sctp.auth_enable,
280 		.maxlen		= sizeof(int),
281 		.mode		= 0644,
282 		.proc_handler	= proc_sctp_do_auth,
283 	},
284 	{
285 		.procname	= "intl_enable",
286 		.data		= &init_net.sctp.intl_enable,
287 		.maxlen		= sizeof(int),
288 		.mode		= 0644,
289 		.proc_handler	= proc_dointvec,
290 	},
291 	{
292 		.procname	= "ecn_enable",
293 		.data		= &init_net.sctp.ecn_enable,
294 		.maxlen		= sizeof(int),
295 		.mode		= 0644,
296 		.proc_handler	= proc_dointvec,
297 	},
298 	{
299 		.procname	= "addr_scope_policy",
300 		.data		= &init_net.sctp.scope_policy,
301 		.maxlen		= sizeof(int),
302 		.mode		= 0644,
303 		.proc_handler	= proc_dointvec_minmax,
304 		.extra1		= SYSCTL_ZERO,
305 		.extra2		= &addr_scope_max,
306 	},
307 	{
308 		.procname	= "rwnd_update_shift",
309 		.data		= &init_net.sctp.rwnd_upd_shift,
310 		.maxlen		= sizeof(int),
311 		.mode		= 0644,
312 		.proc_handler	= &proc_dointvec_minmax,
313 		.extra1		= SYSCTL_ONE,
314 		.extra2		= &rwnd_scale_max,
315 	},
316 	{
317 		.procname	= "max_autoclose",
318 		.data		= &init_net.sctp.max_autoclose,
319 		.maxlen		= sizeof(unsigned long),
320 		.mode		= 0644,
321 		.proc_handler	= &proc_doulongvec_minmax,
322 		.extra1		= &max_autoclose_min,
323 		.extra2		= &max_autoclose_max,
324 	},
325 	{
326 		.procname	= "pf_enable",
327 		.data		= &init_net.sctp.pf_enable,
328 		.maxlen		= sizeof(int),
329 		.mode		= 0644,
330 		.proc_handler	= proc_dointvec,
331 	},
332 	{
333 		.procname	= "pf_expose",
334 		.data		= &init_net.sctp.pf_expose,
335 		.maxlen		= sizeof(int),
336 		.mode		= 0644,
337 		.proc_handler	= proc_dointvec_minmax,
338 		.extra1		= SYSCTL_ZERO,
339 		.extra2		= &pf_expose_max,
340 	},
341 
342 	{ /* sentinel */ }
343 };
344 
345 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
346 				void __user *buffer, size_t *lenp,
347 				loff_t *ppos)
348 {
349 	struct net *net = current->nsproxy->net_ns;
350 	struct ctl_table tbl;
351 	bool changed = false;
352 	char *none = "none";
353 	char tmp[8] = {0};
354 	int ret;
355 
356 	memset(&tbl, 0, sizeof(struct ctl_table));
357 
358 	if (write) {
359 		tbl.data = tmp;
360 		tbl.maxlen = sizeof(tmp);
361 	} else {
362 		tbl.data = net->sctp.sctp_hmac_alg ? : none;
363 		tbl.maxlen = strlen(tbl.data);
364 	}
365 
366 	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
367 	if (write && ret == 0) {
368 #ifdef CONFIG_CRYPTO_MD5
369 		if (!strncmp(tmp, "md5", 3)) {
370 			net->sctp.sctp_hmac_alg = "md5";
371 			changed = true;
372 		}
373 #endif
374 #ifdef CONFIG_CRYPTO_SHA1
375 		if (!strncmp(tmp, "sha1", 4)) {
376 			net->sctp.sctp_hmac_alg = "sha1";
377 			changed = true;
378 		}
379 #endif
380 		if (!strncmp(tmp, "none", 4)) {
381 			net->sctp.sctp_hmac_alg = NULL;
382 			changed = true;
383 		}
384 		if (!changed)
385 			ret = -EINVAL;
386 	}
387 
388 	return ret;
389 }
390 
391 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
392 				void __user *buffer, size_t *lenp,
393 				loff_t *ppos)
394 {
395 	struct net *net = current->nsproxy->net_ns;
396 	unsigned int min = *(unsigned int *) ctl->extra1;
397 	unsigned int max = *(unsigned int *) ctl->extra2;
398 	struct ctl_table tbl;
399 	int ret, new_value;
400 
401 	memset(&tbl, 0, sizeof(struct ctl_table));
402 	tbl.maxlen = sizeof(unsigned int);
403 
404 	if (write)
405 		tbl.data = &new_value;
406 	else
407 		tbl.data = &net->sctp.rto_min;
408 
409 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
410 	if (write && ret == 0) {
411 		if (new_value > max || new_value < min)
412 			return -EINVAL;
413 
414 		net->sctp.rto_min = new_value;
415 	}
416 
417 	return ret;
418 }
419 
420 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
421 				void __user *buffer, size_t *lenp,
422 				loff_t *ppos)
423 {
424 	struct net *net = current->nsproxy->net_ns;
425 	unsigned int min = *(unsigned int *) ctl->extra1;
426 	unsigned int max = *(unsigned int *) ctl->extra2;
427 	struct ctl_table tbl;
428 	int ret, new_value;
429 
430 	memset(&tbl, 0, sizeof(struct ctl_table));
431 	tbl.maxlen = sizeof(unsigned int);
432 
433 	if (write)
434 		tbl.data = &new_value;
435 	else
436 		tbl.data = &net->sctp.rto_max;
437 
438 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
439 	if (write && ret == 0) {
440 		if (new_value > max || new_value < min)
441 			return -EINVAL;
442 
443 		net->sctp.rto_max = new_value;
444 	}
445 
446 	return ret;
447 }
448 
449 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
450 				   void __user *buffer, size_t *lenp,
451 				   loff_t *ppos)
452 {
453 	if (write)
454 		pr_warn_once("Changing rto_alpha or rto_beta may lead to "
455 			     "suboptimal rtt/srtt estimations!\n");
456 
457 	return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
458 }
459 
460 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
461 			     void __user *buffer, size_t *lenp,
462 			     loff_t *ppos)
463 {
464 	struct net *net = current->nsproxy->net_ns;
465 	struct ctl_table tbl;
466 	int new_value, ret;
467 
468 	memset(&tbl, 0, sizeof(struct ctl_table));
469 	tbl.maxlen = sizeof(unsigned int);
470 
471 	if (write)
472 		tbl.data = &new_value;
473 	else
474 		tbl.data = &net->sctp.auth_enable;
475 
476 	ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
477 	if (write && ret == 0) {
478 		struct sock *sk = net->sctp.ctl_sock;
479 
480 		net->sctp.auth_enable = new_value;
481 		/* Update the value in the control socket */
482 		lock_sock(sk);
483 		sctp_sk(sk)->ep->auth_enable = new_value;
484 		release_sock(sk);
485 	}
486 
487 	return ret;
488 }
489 
490 int sctp_sysctl_net_register(struct net *net)
491 {
492 	struct ctl_table *table;
493 	int i;
494 
495 	table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
496 	if (!table)
497 		return -ENOMEM;
498 
499 	for (i = 0; table[i].data; i++)
500 		table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
501 
502 	net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
503 	if (net->sctp.sysctl_header == NULL) {
504 		kfree(table);
505 		return -ENOMEM;
506 	}
507 	return 0;
508 }
509 
510 void sctp_sysctl_net_unregister(struct net *net)
511 {
512 	struct ctl_table *table;
513 
514 	table = net->sctp.sysctl_header->ctl_table_arg;
515 	unregister_net_sysctl_table(net->sctp.sysctl_header);
516 	kfree(table);
517 }
518 
519 static struct ctl_table_header *sctp_sysctl_header;
520 
521 /* Sysctl registration.  */
522 void sctp_sysctl_register(void)
523 {
524 	sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
525 }
526 
527 /* Sysctl deregistration.  */
528 void sctp_sysctl_unregister(void)
529 {
530 	unregister_net_sysctl_table(sctp_sysctl_header);
531 }
532