priv: Narrow down privileges
[dragonfly.git] / sys / kern / kern_sysctl.c
CommitLineData
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1/*-
2 * Copyright (c) 1982, 1986, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Mike Karels at Berkeley Software Design, Inc.
7 *
8 * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD
9 * project, to make these variables more userfriendly.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94
40 * $FreeBSD: src/sys/kern/kern_sysctl.c,v 1.92.2.9 2003/05/01 22:48:09 trhodes Exp $
7efc589a 41 * $DragonFly: src/sys/kern/kern_sysctl.c,v 1.30 2008/08/03 11:00:32 sephe Exp $
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42 */
43
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44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/kernel.h>
47#include <sys/buf.h>
48#include <sys/sysctl.h>
49#include <sys/malloc.h>
50#include <sys/proc.h>
895c1f85 51#include <sys/priv.h>
984263bc 52#include <sys/sysproto.h>
853af6eb 53#include <sys/lock.h>
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54#include <vm/vm.h>
55#include <vm/vm_extern.h>
56
57static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic");
58static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids");
59
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60static struct lock sysctl_lkp;
61static struct lock sysctl_ctx_lkp;
62
63static void sysctl_lock(int type);
64static void sysctl_unlock(void);
65static void sysctl_ctx_lock(int type);
66static void sysctl_ctx_unlock(void);
984263bc 67
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68static int sysctl_root(SYSCTL_HANDLER_ARGS);
69static void sysctl_register_oid_int(struct sysctl_oid *oipd);
70static void sysctl_unregister_oid_int(struct sysctl_oid *oipd);
71static struct sysctl_ctx_entry* sysctl_ctx_entry_find_int
72 (struct sysctl_ctx_list *, struct sysctl_oid *oidp);
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73
74struct sysctl_oid_list sysctl__children; /* root list */
75
76static struct sysctl_oid *
853af6eb 77sysctl_find_oidname(const char *name, struct sysctl_oid_list *list, int lock)
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78{
79 struct sysctl_oid *oidp;
80
81 SLIST_FOREACH(oidp, list, oid_link) {
82 if (strcmp(oidp->oid_name, name) == 0) {
853af6eb 83 break;
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84 }
85 }
853af6eb 86 return (oidp);
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87}
88
89/*
90 * Initialization of the MIB tree.
91 *
92 * Order by number in each list.
93 */
94
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95void
96sysctl_register_oid(struct sysctl_oid *oidp)
97{
98 sysctl_lock(LK_EXCLUSIVE);
99 sysctl_register_oid_int(oidp);
100 sysctl_unlock();
101}
102
103static void
104sysctl_register_oid_int(struct sysctl_oid *oidp)
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105{
106 struct sysctl_oid_list *parent = oidp->oid_parent;
107 struct sysctl_oid *p;
108 struct sysctl_oid *q;
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109
110 /*
111 * First check if another oid with the same name already
112 * exists in the parent's list.
113 */
853af6eb 114 p = sysctl_find_oidname(oidp->oid_name, parent, 0);
984263bc 115 if (p != NULL) {
853af6eb 116 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE)
984263bc 117 p->oid_refcnt++;
853af6eb 118 else
6ea70f76 119 kprintf("can't re-use a leaf (%s)!\n", p->oid_name);
853af6eb 120 return;
984263bc 121 }
853af6eb 122
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123 /*
124 * If this oid has a number OID_AUTO, give it a number which
125 * is greater than any current oid. Make sure it is at least
1e32b918 126 * 256 to leave space for pre-assigned oid numbers.
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127 */
128 if (oidp->oid_number == OID_AUTO) {
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129 int newoid = 0x100; /* minimum AUTO oid */
130
131 /*
132 * Adjust based on highest oid in parent list
133 */
134 SLIST_FOREACH(p, parent, oid_link) {
135 if (newoid <= p->oid_number)
136 newoid = p->oid_number + 1;
137 }
138 oidp->oid_number = newoid;
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139 }
140
141 /*
142 * Insert the oid into the parent's list in order.
143 */
144 q = NULL;
145 SLIST_FOREACH(p, parent, oid_link) {
146 if (oidp->oid_number < p->oid_number)
147 break;
148 q = p;
149 }
150 if (q)
151 SLIST_INSERT_AFTER(q, oidp, oid_link);
152 else
153 SLIST_INSERT_HEAD(parent, oidp, oid_link);
154}
155
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156void
157sysctl_unregister_oid(struct sysctl_oid *oidp)
158{
159 sysctl_lock(LK_EXCLUSIVE);
160 sysctl_unregister_oid_int(oidp);
161 sysctl_unlock();
162}
163
164static void
165sysctl_unregister_oid_int(struct sysctl_oid *oidp)
984263bc 166{
fef0fdf2 167 struct sysctl_oid *p;
984263bc 168
853af6eb 169 if (oidp->oid_number == OID_AUTO)
fc92d4aa 170 panic("Trying to unregister OID_AUTO entry: %p", oidp);
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171
172 SLIST_FOREACH(p, oidp->oid_parent, oid_link) {
173 if (p != oidp)
174 continue;
175 SLIST_REMOVE(oidp->oid_parent, oidp, sysctl_oid, oid_link);
176 return;
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177 }
178
179 /*
180 * This can happen when a module fails to register and is
181 * being unloaded afterwards. It should not be a panic()
182 * for normal use.
183 */
6ea70f76 184 kprintf("%s: failed to unregister sysctl\n", __func__);
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185}
186
187/* Initialize a new context to keep track of dynamically added sysctls. */
188int
189sysctl_ctx_init(struct sysctl_ctx_list *c)
190{
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191 if (c == NULL)
192 return(EINVAL);
984263bc 193 TAILQ_INIT(c);
853af6eb 194 return(0);
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195}
196
197/* Free the context, and destroy all dynamic oids registered in this context */
198int
199sysctl_ctx_free(struct sysctl_ctx_list *clist)
200{
201 struct sysctl_ctx_entry *e, *e1;
202 int error;
203
204 error = 0;
853af6eb 205 sysctl_ctx_lock(LK_EXCLUSIVE);
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206 /*
207 * First perform a "dry run" to check if it's ok to remove oids.
208 * XXX FIXME
209 * XXX This algorithm is a hack. But I don't know any
210 * XXX better solution for now...
211 */
212 TAILQ_FOREACH(e, clist, link) {
213 error = sysctl_remove_oid(e->entry, 0, 0);
214 if (error)
215 break;
216 }
217 /*
218 * Restore deregistered entries, either from the end,
219 * or from the place where error occured.
220 * e contains the entry that was not unregistered
221 */
222 if (error)
223 e1 = TAILQ_PREV(e, sysctl_ctx_list, link);
224 else
225 e1 = TAILQ_LAST(clist, sysctl_ctx_list);
226 while (e1 != NULL) {
227 sysctl_register_oid(e1->entry);
228 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link);
229 }
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230 if (error) {
231 sysctl_ctx_unlock();
984263bc 232 return(EBUSY);
853af6eb 233 }
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234 /* Now really delete the entries */
235 e = TAILQ_FIRST(clist);
236 while (e != NULL) {
237 e1 = TAILQ_NEXT(e, link);
238 error = sysctl_remove_oid(e->entry, 1, 0);
239 if (error)
240 panic("sysctl_remove_oid: corrupt tree, entry: %s",
241 e->entry->oid_name);
efda3bd0 242 kfree(e, M_SYSCTLOID);
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243 e = e1;
244 }
853af6eb 245 sysctl_ctx_unlock();
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246 return (error);
247}
248
249/* Add an entry to the context */
250struct sysctl_ctx_entry *
251sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
252{
253 struct sysctl_ctx_entry *e;
254
255 if (clist == NULL || oidp == NULL)
256 return(NULL);
efda3bd0 257 e = kmalloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK);
984263bc 258 e->entry = oidp;
853af6eb 259 sysctl_ctx_lock(LK_EXCLUSIVE);
984263bc 260 TAILQ_INSERT_HEAD(clist, e, link);
853af6eb 261 sysctl_ctx_unlock();
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262 return (e);
263}
264
265/* Find an entry in the context */
266struct sysctl_ctx_entry *
267sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
268{
269 struct sysctl_ctx_entry *e;
270
271 if (clist == NULL || oidp == NULL)
272 return(NULL);
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273
274 sysctl_ctx_lock(LK_SHARED);
275 e = sysctl_ctx_entry_find_int(clist, oidp);
276 sysctl_ctx_unlock();
277
278 return(e);
279}
280
281struct sysctl_ctx_entry *
282sysctl_ctx_entry_find_int(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
283{
284 struct sysctl_ctx_entry *e;
285
286 KKASSERT(clist != NULL && oidp != NULL);
287
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288 for (e = TAILQ_FIRST(clist); e != NULL; e = TAILQ_NEXT(e, link)) {
289 if(e->entry == oidp)
853af6eb 290 break;
984263bc 291 }
853af6eb 292
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293 return (e);
294}
295
296/*
297 * Delete an entry from the context.
298 * NOTE: this function doesn't free oidp! You have to remove it
299 * with sysctl_remove_oid().
300 */
301int
302sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
303{
304 struct sysctl_ctx_entry *e;
305
306 if (clist == NULL || oidp == NULL)
307 return (EINVAL);
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308
309 sysctl_ctx_lock(LK_EXCLUSIVE);
310 e = sysctl_ctx_entry_find_int(clist, oidp);
311 if (e == NULL) {
312 sysctl_ctx_unlock();
984263bc 313 return (ENOENT);
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314 }
315 TAILQ_REMOVE(clist, e, link);
efda3bd0 316 kfree(e, M_SYSCTLOID);
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317 sysctl_ctx_unlock();
318
319 return(0);
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320}
321
322/*
323 * Remove dynamically created sysctl trees.
324 * oidp - top of the tree to be removed
325 * del - if 0 - just deregister, otherwise free up entries as well
326 * recurse - if != 0 traverse the subtree to be deleted
327 */
328int
329sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse)
330{
331 struct sysctl_oid *p;
332 int error;
333
334 if (oidp == NULL)
335 return(EINVAL);
336 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) {
6ea70f76 337 kprintf("can't remove non-dynamic nodes!\n");
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338 return (EINVAL);
339 }
853af6eb 340 sysctl_lock(LK_EXCLUSIVE | LK_CANRECURSE);
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341 /*
342 * WARNING: normal method to do this should be through
343 * sysctl_ctx_free(). Use recursing as the last resort
344 * method to purge your sysctl tree of leftovers...
345 * However, if some other code still references these nodes,
346 * it will panic.
347 */
348 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
349 if (oidp->oid_refcnt == 1) {
350 SLIST_FOREACH(p, SYSCTL_CHILDREN(oidp), oid_link) {
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351 if (!recurse) {
352 sysctl_unlock();
353 return(ENOTEMPTY);
354 }
984263bc 355 error = sysctl_remove_oid(p, del, recurse);
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356 if (error) {
357 sysctl_unlock();
358 return(error);
359 }
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360 }
361 if (del)
efda3bd0 362 kfree(SYSCTL_CHILDREN(oidp), M_SYSCTLOID);
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363 }
364 }
365 if (oidp->oid_refcnt > 1 ) {
366 oidp->oid_refcnt--;
367 } else {
368 if (oidp->oid_refcnt == 0) {
6ea70f76 369 kprintf("Warning: bad oid_refcnt=%u (%s)!\n",
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370 oidp->oid_refcnt, oidp->oid_name);
371 sysctl_unlock();
372 return(EINVAL);
984263bc 373 }
853af6eb 374 sysctl_unregister_oid_int(oidp);
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375 if (del) {
376 if (oidp->oid_descr)
efda3bd0 377 kfree(__DECONST(char *,oidp->oid_descr),
853af6eb 378 M_SYSCTLOID);
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379 kfree(__DECONST(char *, oidp->oid_name), M_SYSCTLOID);
380 kfree(oidp, M_SYSCTLOID);
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381 }
382 }
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383 sysctl_unlock();
384 return(0);
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385}
386
387/*
388 * Create new sysctls at run time.
389 * clist may point to a valid context initialized with sysctl_ctx_init().
390 */
391struct sysctl_oid *
392sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent,
393 int number, const char *name, int kind, void *arg1, int arg2,
394 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr)
395{
396 struct sysctl_oid *oidp;
397 ssize_t len;
398 char *newname;
399
400 /* You have to hook up somewhere.. */
401 if (parent == NULL)
402 return(NULL);
853af6eb 403 sysctl_lock(LK_EXCLUSIVE);
984263bc 404 /* Check if the node already exists, otherwise create it */
853af6eb 405 oidp = sysctl_find_oidname(name, parent, 0);
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406 if (oidp != NULL) {
407 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
408 oidp->oid_refcnt++;
409 /* Update the context */
410 if (clist != NULL)
411 sysctl_ctx_entry_add(clist, oidp);
853af6eb 412 sysctl_unlock();
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413 return (oidp);
414 } else {
6ea70f76 415 kprintf("can't re-use a leaf (%s)!\n", name);
853af6eb 416 sysctl_unlock();
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417 return (NULL);
418 }
419 }
efda3bd0 420 oidp = kmalloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK | M_ZERO);
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421 oidp->oid_parent = parent;
422 SLIST_NEXT(oidp, oid_link) = NULL;
423 oidp->oid_number = number;
424 oidp->oid_refcnt = 1;
425 len = strlen(name);
efda3bd0 426 newname = kmalloc(len + 1, M_SYSCTLOID, M_WAITOK);
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427 bcopy(name, newname, len + 1);
428 newname[len] = '\0';
429 oidp->oid_name = newname;
430 oidp->oid_handler = handler;
431 oidp->oid_kind = CTLFLAG_DYN | kind;
432 if ((kind & CTLTYPE) == CTLTYPE_NODE) {
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433 struct sysctl_oid_list *children;
434
984263bc 435 /* Allocate space for children */
efda3bd0 436 children = kmalloc(sizeof(*children), M_SYSCTLOID, M_WAITOK);
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437 SYSCTL_SET_CHILDREN(oidp, children);
438 SLIST_INIT(children);
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439 } else {
440 oidp->oid_arg1 = arg1;
441 oidp->oid_arg2 = arg2;
442 }
443 oidp->oid_fmt = fmt;
444 if (descr) {
445 int len = strlen(descr) + 1;
efda3bd0 446 oidp->oid_descr = kmalloc(len, M_SYSCTLOID, M_WAITOK);
978400d3 447 strcpy((char *)(uintptr_t)(const void *)oidp->oid_descr, descr);
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448 };
449 /* Update the context, if used */
450 if (clist != NULL)
451 sysctl_ctx_entry_add(clist, oidp);
452 /* Register this oid */
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453 sysctl_register_oid_int(oidp);
454 sysctl_unlock();
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455 return (oidp);
456}
457
458/*
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459 * Register the kernel's oids on startup.
460 */
dc62b251 461SET_DECLARE(sysctl_set, struct sysctl_oid);
984263bc 462
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463static void
464sysctl_register_all(void *arg)
984263bc 465{
dc62b251 466 struct sysctl_oid **oidp;
984263bc 467
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468 lockinit(&sysctl_lkp, "sysctl", 0, 0);
469 lockinit(&sysctl_ctx_lkp, "sysctl ctx", 0, 0);
dc62b251 470 SET_FOREACH(oidp, sysctl_set)
853af6eb 471 sysctl_register_oid_int(*oidp);
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472}
473
ba39e2e0 474SYSINIT(sysctl, SI_BOOT1_POST, SI_ORDER_ANY, sysctl_register_all, 0);
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475
476/*
477 * "Staff-functions"
478 *
479 * These functions implement a presently undocumented interface
480 * used by the sysctl program to walk the tree, and get the type
481 * so it can print the value.
482 * This interface is under work and consideration, and should probably
483 * be killed with a big axe by the first person who can find the time.
484 * (be aware though, that the proper interface isn't as obvious as it
485 * may seem, there are various conflicting requirements.
486 *
6ea70f76 487 * {0,0} kprintf the entire MIB-tree.
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488 * {0,1,...} return the name of the "..." OID.
489 * {0,2,...} return the next OID.
490 * {0,3} return the OID of the name in "new"
491 * {0,4,...} return the kind & format info for the "..." OID.
492 */
493
494static void
495sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i)
496{
497 int k;
498 struct sysctl_oid *oidp;
499
853af6eb 500 sysctl_lock(LK_SHARED);
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501 SLIST_FOREACH(oidp, l, oid_link) {
502
503 for (k=0; k<i; k++)
6ea70f76 504 kprintf(" ");
984263bc 505
6ea70f76 506 kprintf("%d %s ", oidp->oid_number, oidp->oid_name);
984263bc 507
6ea70f76 508 kprintf("%c%c",
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509 oidp->oid_kind & CTLFLAG_RD ? 'R':' ',
510 oidp->oid_kind & CTLFLAG_WR ? 'W':' ');
511
512 if (oidp->oid_handler)
6ea70f76 513 kprintf(" *Handler");
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514
515 switch (oidp->oid_kind & CTLTYPE) {
516 case CTLTYPE_NODE:
6ea70f76 517 kprintf(" Node\n");
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518 if (!oidp->oid_handler) {
519 sysctl_sysctl_debug_dump_node(
520 oidp->oid_arg1, i+2);
521 }
522 break;
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523 case CTLTYPE_INT: kprintf(" Int\n"); break;
524 case CTLTYPE_STRING: kprintf(" String\n"); break;
525 case CTLTYPE_QUAD: kprintf(" Quad\n"); break;
526 case CTLTYPE_OPAQUE: kprintf(" Opaque/struct\n"); break;
527 default: kprintf("\n");
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528 }
529
530 }
853af6eb 531 sysctl_unlock();
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532}
533
534static int
535sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS)
536{
537 int error;
538
3b1d99e9 539 error = priv_check(req->td, PRIV_SYSCTL_DEBUG);
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540 if (error)
541 return error;
542 sysctl_sysctl_debug_dump_node(&sysctl__children, 0);
543 return ENOENT;
544}
545
546SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD,
547 0, 0, sysctl_sysctl_debug, "-", "");
548
549static int
550sysctl_sysctl_name(SYSCTL_HANDLER_ARGS)
551{
552 int *name = (int *) arg1;
553 u_int namelen = arg2;
554 int error = 0;
555 struct sysctl_oid *oid;
556 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2;
557 char buf[10];
558
853af6eb 559 sysctl_lock(LK_SHARED);
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560 while (namelen) {
561 if (!lsp) {
f8c7a42d 562 ksnprintf(buf,sizeof(buf),"%d",*name);
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563 if (req->oldidx)
564 error = SYSCTL_OUT(req, ".", 1);
565 if (!error)
566 error = SYSCTL_OUT(req, buf, strlen(buf));
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567 if (error) {
568 sysctl_unlock();
984263bc 569 return (error);
853af6eb 570 }
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571 namelen--;
572 name++;
573 continue;
574 }
575 lsp2 = 0;
576 SLIST_FOREACH(oid, lsp, oid_link) {
577 if (oid->oid_number != *name)
578 continue;
579
580 if (req->oldidx)
581 error = SYSCTL_OUT(req, ".", 1);
582 if (!error)
583 error = SYSCTL_OUT(req, oid->oid_name,
584 strlen(oid->oid_name));
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585 if (error) {
586 sysctl_unlock();
984263bc 587 return (error);
853af6eb 588 }
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589
590 namelen--;
591 name++;
592
593 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE)
594 break;
595
596 if (oid->oid_handler)
597 break;
598
599 lsp2 = (struct sysctl_oid_list *)oid->oid_arg1;
600 break;
601 }
602 lsp = lsp2;
603 }
853af6eb 604 sysctl_unlock();
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605 return (SYSCTL_OUT(req, "", 1));
606}
607
608SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD, sysctl_sysctl_name, "");
609
610static int
611sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen,
612 int *next, int *len, int level, struct sysctl_oid **oidpp)
613{
614 struct sysctl_oid *oidp;
615
616 *len = level;
853af6eb 617 sysctl_lock(LK_SHARED);
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618 SLIST_FOREACH(oidp, lsp, oid_link) {
619 *next = oidp->oid_number;
620 *oidpp = oidp;
621
622 if (!namelen) {
853af6eb
JS
623 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) {
624 sysctl_unlock();
984263bc 625 return 0;
853af6eb
JS
626 }
627 if (oidp->oid_handler) {
984263bc 628 /* We really should call the handler here...*/
853af6eb 629 sysctl_unlock();
984263bc 630 return 0;
853af6eb 631 }
984263bc
MD
632 lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
633 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1,
853af6eb
JS
634 len, level+1, oidpp)) {
635 sysctl_unlock();
984263bc 636 return 0;
853af6eb 637 }
fef0fdf2 638 goto emptynode;
984263bc
MD
639 }
640
641 if (oidp->oid_number < *name)
642 continue;
643
644 if (oidp->oid_number > *name) {
853af6eb
JS
645 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) {
646 sysctl_unlock();
984263bc 647 return 0;
853af6eb
JS
648 }
649 if (oidp->oid_handler) {
650 sysctl_unlock();
984263bc 651 return 0;
853af6eb 652 }
984263bc
MD
653 lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
654 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1,
853af6eb
JS
655 next+1, len, level+1, oidpp)) {
656 sysctl_unlock();
984263bc 657 return (0);
853af6eb 658 }
984263bc
MD
659 goto next;
660 }
661 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
662 continue;
663
664 if (oidp->oid_handler)
665 continue;
666
667 lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
668 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1,
853af6eb
JS
669 len, level+1, oidpp)) {
670 sysctl_unlock();
984263bc 671 return (0);
853af6eb 672 }
984263bc
MD
673 next:
674 namelen = 1;
675 *len = level;
fef0fdf2
MD
676 emptynode:
677 *len = level;
984263bc 678 }
853af6eb 679 sysctl_unlock();
984263bc
MD
680 return 1;
681}
682
683static int
684sysctl_sysctl_next(SYSCTL_HANDLER_ARGS)
685{
686 int *name = (int *) arg1;
687 u_int namelen = arg2;
688 int i, j, error;
689 struct sysctl_oid *oid;
690 struct sysctl_oid_list *lsp = &sysctl__children;
691 int newoid[CTL_MAXNAME];
692
693 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid);
694 if (i)
695 return ENOENT;
696 error = SYSCTL_OUT(req, newoid, j * sizeof (int));
697 return (error);
698}
699
700SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD, sysctl_sysctl_next, "");
701
702static int
703name2oid (char *name, int *oid, int *len, struct sysctl_oid **oidpp)
704{
705 int i;
706 struct sysctl_oid *oidp;
707 struct sysctl_oid_list *lsp = &sysctl__children;
708 char *p;
709
710 if (!*name)
711 return ENOENT;
712
713 p = name + strlen(name) - 1 ;
714 if (*p == '.')
715 *p = '\0';
716
717 *len = 0;
718
719 for (p = name; *p && *p != '.'; p++)
720 ;
721 i = *p;
722 if (i == '.')
723 *p = '\0';
724
853af6eb 725 sysctl_lock(LK_SHARED);
984263bc
MD
726 oidp = SLIST_FIRST(lsp);
727
728 while (oidp && *len < CTL_MAXNAME) {
729 if (strcmp(name, oidp->oid_name)) {
730 oidp = SLIST_NEXT(oidp, oid_link);
731 continue;
732 }
733 *oid++ = oidp->oid_number;
734 (*len)++;
735
736 if (!i) {
737 if (oidpp)
738 *oidpp = oidp;
853af6eb 739 sysctl_unlock();
984263bc
MD
740 return (0);
741 }
742
743 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
744 break;
745
746 if (oidp->oid_handler)
747 break;
748
749 lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
750 oidp = SLIST_FIRST(lsp);
751 name = p+1;
752 for (p = name; *p && *p != '.'; p++)
753 ;
754 i = *p;
755 if (i == '.')
756 *p = '\0';
757 }
853af6eb 758 sysctl_unlock();
984263bc
MD
759 return ENOENT;
760}
761
762static int
763sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS)
764{
765 char *p;
766 int error, oid[CTL_MAXNAME], len;
767 struct sysctl_oid *op = 0;
768
769 if (!req->newlen)
770 return ENOENT;
771 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */
772 return (ENAMETOOLONG);
773
efda3bd0 774 p = kmalloc(req->newlen+1, M_SYSCTL, M_WAITOK);
984263bc
MD
775
776 error = SYSCTL_IN(req, p, req->newlen);
777 if (error) {
efda3bd0 778 kfree(p, M_SYSCTL);
984263bc
MD
779 return (error);
780 }
781
782 p [req->newlen] = '\0';
783
784 error = name2oid(p, oid, &len, &op);
785
efda3bd0 786 kfree(p, M_SYSCTL);
984263bc
MD
787
788 if (error)
789 return (error);
790
791 error = SYSCTL_OUT(req, oid, len * sizeof *oid);
792 return (error);
793}
794
795SYSCTL_PROC(_sysctl, 3, name2oid, CTLFLAG_RW|CTLFLAG_ANYBODY, 0, 0,
796 sysctl_sysctl_name2oid, "I", "");
797
798static int
799sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS)
800{
801 struct sysctl_oid *oid;
802 int error;
803
804 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
805 if (error)
806 return (error);
807
808 if (!oid->oid_fmt)
809 return (ENOENT);
810 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind));
811 if (error)
812 return (error);
813 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1);
814 return (error);
815}
816
817
818SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD, sysctl_sysctl_oidfmt, "");
819
820static int
821sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS)
822{
823 struct sysctl_oid *oid;
824 int error;
825
826 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
827 if (error)
828 return (error);
829
830 if (!oid->oid_descr)
831 return (ENOENT);
832 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1);
833 return (error);
834}
835
836SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD, sysctl_sysctl_oiddescr, "");
837
838/*
839 * Default "handler" functions.
840 */
841
842/*
843 * Handle an int, signed or unsigned.
844 * Two cases:
845 * a variable: point arg1 at it.
846 * a constant: pass it in arg2.
847 */
848
849int
850sysctl_handle_int(SYSCTL_HANDLER_ARGS)
851{
852 int error = 0;
853
854 if (arg1)
855 error = SYSCTL_OUT(req, arg1, sizeof(int));
856 else
857 error = SYSCTL_OUT(req, &arg2, sizeof(int));
858
859 if (error || !req->newptr)
860 return (error);
861
862 if (!arg1)
863 error = EPERM;
864 else
865 error = SYSCTL_IN(req, arg1, sizeof(int));
866 return (error);
867}
868
869/*
870 * Handle a long, signed or unsigned. arg1 points to it.
871 */
872
873int
874sysctl_handle_long(SYSCTL_HANDLER_ARGS)
875{
876 int error = 0;
877
878 if (!arg1)
879 return (EINVAL);
880 error = SYSCTL_OUT(req, arg1, sizeof(long));
881
882 if (error || !req->newptr)
883 return (error);
884
885 error = SYSCTL_IN(req, arg1, sizeof(long));
886 return (error);
887}
888
889/*
5f2e2a8b
MD
890 * Handle a quad, signed or unsigned. arg1 points to it.
891 */
892
893int
894sysctl_handle_quad(SYSCTL_HANDLER_ARGS)
895{
896 int error = 0;
897
898 if (!arg1)
899 return (EINVAL);
900 error = SYSCTL_OUT(req, arg1, sizeof(quad_t));
901
902 if (error || !req->newptr)
903 return (error);
904
905 error = SYSCTL_IN(req, arg1, sizeof(quad_t));
906 return (error);
907}
908
909/*
984263bc
MD
910 * Handle our generic '\0' terminated 'C' string.
911 * Two cases:
912 * a variable string: point arg1 at it, arg2 is max length.
913 * a constant string: point arg1 at it, arg2 is zero.
914 */
915
916int
917sysctl_handle_string(SYSCTL_HANDLER_ARGS)
918{
919 int error=0;
920
921 error = SYSCTL_OUT(req, arg1, strlen((char *)arg1)+1);
922
923 if (error || !req->newptr)
924 return (error);
925
926 if ((req->newlen - req->newidx) >= arg2) {
927 error = EINVAL;
928 } else {
929 arg2 = (req->newlen - req->newidx);
930 error = SYSCTL_IN(req, arg1, arg2);
931 ((char *)arg1)[arg2] = '\0';
932 }
933
934 return (error);
935}
936
937/*
938 * Handle any kind of opaque data.
939 * arg1 points to it, arg2 is the size.
940 */
941
942int
943sysctl_handle_opaque(SYSCTL_HANDLER_ARGS)
944{
945 int error;
946
947 error = SYSCTL_OUT(req, arg1, arg2);
948
949 if (error || !req->newptr)
950 return (error);
951
952 error = SYSCTL_IN(req, arg1, arg2);
953
954 return (error);
955}
956
957/*
958 * Transfer functions to/from kernel space.
959 * XXX: rather untested at this point
960 */
961static int
962sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l)
963{
964 size_t i = 0;
965
966 if (req->oldptr) {
967 i = l;
968 if (i > req->oldlen - req->oldidx)
969 i = req->oldlen - req->oldidx;
970 if (i > 0)
971 bcopy(p, (char *)req->oldptr + req->oldidx, i);
972 }
973 req->oldidx += l;
974 if (req->oldptr && i != l)
975 return (ENOMEM);
976 return (0);
977}
978
979static int
980sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l)
981{
982
983 if (!req->newptr)
984 return 0;
985 if (req->newlen - req->newidx < l)
986 return (EINVAL);
987 bcopy((char *)req->newptr + req->newidx, p, l);
988 req->newidx += l;
989 return (0);
990}
991
992int
41c20dac 993kernel_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval)
984263bc
MD
994{
995 int error = 0;
996 struct sysctl_req req;
997
998 bzero(&req, sizeof req);
999
dadab5e9 1000 req.td = curthread;
984263bc
MD
1001
1002 if (oldlenp) {
1003 req.oldlen = *oldlenp;
1004 }
1005
1006 if (old) {
41c20dac 1007 req.oldptr = old;
984263bc
MD
1008 }
1009
1010 if (new != NULL) {
1011 req.newlen = newlen;
1012 req.newptr = new;
1013 }
1014
1015 req.oldfunc = sysctl_old_kernel;
1016 req.newfunc = sysctl_new_kernel;
1017 req.lock = 1;
1018
853af6eb 1019 sysctl_lock(LK_SHARED);
984263bc
MD
1020
1021 error = sysctl_root(0, name, namelen, &req);
1022
1023 if (req.lock == 2)
1024 vsunlock(req.oldptr, req.oldlen);
1025
853af6eb 1026 sysctl_unlock();
984263bc
MD
1027
1028 if (error && error != ENOMEM)
1029 return (error);
1030
1031 if (retval) {
1032 if (req.oldptr && req.oldidx > req.oldlen)
1033 *retval = req.oldlen;
1034 else
1035 *retval = req.oldidx;
1036 }
1037 return (error);
1038}
1039
1040int
41c20dac 1041kernel_sysctlbyname(char *name, void *old, size_t *oldlenp,
984263bc
MD
1042 void *new, size_t newlen, size_t *retval)
1043{
1044 int oid[CTL_MAXNAME];
1045 size_t oidlen, plen;
1046 int error;
1047
1048 oid[0] = 0; /* sysctl internal magic */
1049 oid[1] = 3; /* name2oid */
1050 oidlen = sizeof(oid);
1051
41c20dac
MD
1052 error = kernel_sysctl(oid, 2, oid, &oidlen, (void *)name,
1053 strlen(name), &plen);
984263bc
MD
1054 if (error)
1055 return (error);
1056
41c20dac 1057 error = kernel_sysctl(oid, plen / sizeof(int), old, oldlenp,
984263bc
MD
1058 new, newlen, retval);
1059 return (error);
1060}
1061
1062/*
1063 * Transfer function to/from user space.
1064 */
1065static int
1066sysctl_old_user(struct sysctl_req *req, const void *p, size_t l)
1067{
1068 int error = 0;
1069 size_t i = 0;
1070
1071 if (req->lock == 1 && req->oldptr) {
1072 vslock(req->oldptr, req->oldlen);
1073 req->lock = 2;
1074 }
1075 if (req->oldptr) {
1076 i = l;
1077 if (i > req->oldlen - req->oldidx)
1078 i = req->oldlen - req->oldidx;
1079 if (i > 0)
1080 error = copyout(p, (char *)req->oldptr + req->oldidx,
1081 i);
1082 }
1083 req->oldidx += l;
1084 if (error)
1085 return (error);
1086 if (req->oldptr && i < l)
1087 return (ENOMEM);
1088 return (0);
1089}
1090
1091static int
1092sysctl_new_user(struct sysctl_req *req, void *p, size_t l)
1093{
1094 int error;
1095
1096 if (!req->newptr)
1097 return 0;
1098 if (req->newlen - req->newidx < l)
1099 return (EINVAL);
1100 error = copyin((char *)req->newptr + req->newidx, p, l);
1101 req->newidx += l;
1102 return (error);
1103}
1104
1105int
1106sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid,
1107 int *nindx, struct sysctl_req *req)
1108{
1109 struct sysctl_oid *oid;
1110 int indx;
1111
853af6eb 1112 sysctl_lock(LK_SHARED);
984263bc
MD
1113 oid = SLIST_FIRST(&sysctl__children);
1114 indx = 0;
1115 while (oid && indx < CTL_MAXNAME) {
1116 if (oid->oid_number == name[indx]) {
1117 indx++;
1118 if (oid->oid_kind & CTLFLAG_NOLOCK)
1119 req->lock = 0;
1120 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
1121 if (oid->oid_handler != NULL ||
1122 indx == namelen) {
1123 *noid = oid;
1124 if (nindx != NULL)
1125 *nindx = indx;
853af6eb 1126 sysctl_unlock();
984263bc
MD
1127 return (0);
1128 }
1129 oid = SLIST_FIRST(
1130 (struct sysctl_oid_list *)oid->oid_arg1);
1131 } else if (indx == namelen) {
1132 *noid = oid;
1133 if (nindx != NULL)
1134 *nindx = indx;
853af6eb 1135 sysctl_unlock();
984263bc
MD
1136 return (0);
1137 } else {
853af6eb 1138 sysctl_unlock();
984263bc
MD
1139 return (ENOTDIR);
1140 }
1141 } else {
1142 oid = SLIST_NEXT(oid, oid_link);
1143 }
1144 }
853af6eb 1145 sysctl_unlock();
984263bc
MD
1146 return (ENOENT);
1147}
1148
1149/*
1150 * Traverse our tree, and find the right node, execute whatever it points
1151 * to, and return the resulting error code.
1152 */
1153
1154int
1155sysctl_root(SYSCTL_HANDLER_ARGS)
1156{
dadab5e9
MD
1157 struct thread *td = req->td;
1158 struct proc *p = td ? td->td_proc : NULL;
984263bc
MD
1159 struct sysctl_oid *oid;
1160 int error, indx;
1161
1162 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req);
1163 if (error)
1164 return (error);
1165
1166 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
1167 /*
1168 * You can't call a sysctl when it's a node, but has
1169 * no handler. Inform the user that it's a node.
1170 * The indx may or may not be the same as namelen.
1171 */
1172 if (oid->oid_handler == NULL)
1173 return (EISDIR);
1174 }
1175
1176 /* If writing isn't allowed */
1177 if (req->newptr && (!(oid->oid_kind & CTLFLAG_WR) ||
1178 ((oid->oid_kind & CTLFLAG_SECURE) && securelevel > 0)))
1179 return (EPERM);
1180
1181 /* Most likely only root can write */
26a0694b 1182 if (!(oid->oid_kind & CTLFLAG_ANYBODY) && req->newptr && p &&
895c1f85 1183 (error = priv_check_cred(p->p_ucred, PRIV_ROOT,
41c20dac 1184 (oid->oid_kind & CTLFLAG_PRISON) ? PRISON_ROOT : 0)))
984263bc
MD
1185 return (error);
1186
1187 if (!oid->oid_handler)
1188 return EINVAL;
1189
1190 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE)
1191 error = oid->oid_handler(oid, (int *)arg1 + indx, arg2 - indx,
1192 req);
1193 else
1194 error = oid->oid_handler(oid, oid->oid_arg1, oid->oid_arg2,
1195 req);
1196 return (error);
1197}
1198
984263bc 1199int
753fd850 1200sys___sysctl(struct sysctl_args *uap)
984263bc
MD
1201{
1202 int error, i, name[CTL_MAXNAME];
1203 size_t j;
1204
1205 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2)
1206 return (EINVAL);
1207
1208 error = copyin(uap->name, &name, uap->namelen * sizeof(int));
1209 if (error)
1210 return (error);
1211
41c20dac 1212 error = userland_sysctl(name, uap->namelen,
984263bc
MD
1213 uap->old, uap->oldlenp, 0,
1214 uap->new, uap->newlen, &j);
1215 if (error && error != ENOMEM)
1216 return (error);
1217 if (uap->oldlenp) {
1218 i = copyout(&j, uap->oldlenp, sizeof(j));
1219 if (i)
1220 return (i);
1221 }
1222 return (error);
1223}
1224
1225/*
1226 * This is used from various compatibility syscalls too. That's why name
1227 * must be in kernel space.
1228 */
1229int
41c20dac 1230userland_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval)
984263bc
MD
1231{
1232 int error = 0;
1233 struct sysctl_req req, req2;
1234
1235 bzero(&req, sizeof req);
1236
984263bc
MD
1237 if (oldlenp) {
1238 if (inkernel) {
1239 req.oldlen = *oldlenp;
1240 } else {
1241 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp));
1242 if (error)
1243 return (error);
1244 }
1245 }
1246
1247 if (old) {
1248 if (!useracc(old, req.oldlen, VM_PROT_WRITE))
1249 return (EFAULT);
1250 req.oldptr= old;
1251 }
1252
1253 if (new != NULL) {
9328e781 1254 if (!useracc(new, newlen, VM_PROT_READ))
984263bc
MD
1255 return (EFAULT);
1256 req.newlen = newlen;
1257 req.newptr = new;
1258 }
1259
1260 req.oldfunc = sysctl_old_user;
1261 req.newfunc = sysctl_new_user;
1262 req.lock = 1;
5f2e2a8b 1263 req.td = curthread;
984263bc 1264
853af6eb 1265 sysctl_lock(LK_SHARED);
984263bc
MD
1266
1267 do {
1268 req2 = req;
1269 error = sysctl_root(0, name, namelen, &req2);
1270 } while (error == EAGAIN);
1271
1272 req = req2;
1273 if (req.lock == 2)
1274 vsunlock(req.oldptr, req.oldlen);
1275
853af6eb 1276 sysctl_unlock();
984263bc
MD
1277
1278 if (error && error != ENOMEM)
1279 return (error);
1280
1281 if (retval) {
1282 if (req.oldptr && req.oldidx > req.oldlen)
1283 *retval = req.oldlen;
1284 else
1285 *retval = req.oldidx;
1286 }
1287 return (error);
1288}
853af6eb
JS
1289
1290static void
1291sysctl_lock(int flag)
1292{
df4f70a6 1293 lockmgr(&sysctl_lkp, flag);
853af6eb
JS
1294}
1295
1296static void
1297sysctl_unlock(void)
1298{
df4f70a6 1299 lockmgr(&sysctl_lkp, LK_RELEASE);
853af6eb
JS
1300}
1301
1302static void
1303sysctl_ctx_lock(int flag)
1304{
df4f70a6 1305 lockmgr(&sysctl_ctx_lkp, flag);
853af6eb
JS
1306}
1307
1308static void
1309sysctl_ctx_unlock(void)
1310{
df4f70a6 1311 lockmgr(&sysctl_ctx_lkp, LK_RELEASE);
853af6eb 1312}
df4f70a6 1313
7efc589a
SZ
1314int
1315sysctl_int_range(SYSCTL_HANDLER_ARGS, int low, int high)
1316{
1317 int error, value;
1318
1319 value = *(int *)arg1;
1320 error = sysctl_handle_int(oidp, &value, 0, req);
1321 if (error || !req->newptr)
1322 return (error);
1323 if (value < low || value > high)
1324 return (EINVAL);
1325 *(int *)arg1 = value;
1326 return (0);
1327}