2 * Copyright (c) 1982, 1986, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Mike Karels at Berkeley Software Design, Inc.
8 * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD
9 * project, to make these variables more userfriendly.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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
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 $
41 * $DragonFly: src/sys/kern/kern_sysctl.c,v 1.26 2006/12/23 23:47:54 swildner Exp $
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
48 #include <sys/sysctl.h>
49 #include <sys/malloc.h>
51 #include <sys/sysproto.h>
54 #include <vm/vm_extern.h>
56 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic");
57 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids");
59 static struct lock sysctl_lkp;
60 static struct lock sysctl_ctx_lkp;
62 static void sysctl_lock(int type);
63 static void sysctl_unlock(void);
64 static void sysctl_ctx_lock(int type);
65 static void sysctl_ctx_unlock(void);
67 static int sysctl_root(SYSCTL_HANDLER_ARGS);
68 static void sysctl_register_oid_int(struct sysctl_oid *oipd);
69 static void sysctl_unregister_oid_int(struct sysctl_oid *oipd);
70 static struct sysctl_ctx_entry* sysctl_ctx_entry_find_int
71 (struct sysctl_ctx_list *, struct sysctl_oid *oidp);
73 struct sysctl_oid_list sysctl__children; /* root list */
75 static struct sysctl_oid *
76 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list, int lock)
78 struct sysctl_oid *oidp;
80 SLIST_FOREACH(oidp, list, oid_link) {
81 if (strcmp(oidp->oid_name, name) == 0) {
89 * Initialization of the MIB tree.
91 * Order by number in each list.
95 sysctl_register_oid(struct sysctl_oid *oidp)
97 sysctl_lock(LK_EXCLUSIVE);
98 sysctl_register_oid_int(oidp);
103 sysctl_register_oid_int(struct sysctl_oid *oidp)
105 struct sysctl_oid_list *parent = oidp->oid_parent;
106 struct sysctl_oid *p;
107 struct sysctl_oid *q;
110 * First check if another oid with the same name already
111 * exists in the parent's list.
113 p = sysctl_find_oidname(oidp->oid_name, parent, 0);
115 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE)
118 kprintf("can't re-use a leaf (%s)!\n", p->oid_name);
123 * If this oid has a number OID_AUTO, give it a number which
124 * is greater than any current oid. Make sure it is at least
125 * 256 to leave space for pre-assigned oid numbers.
127 if (oidp->oid_number == OID_AUTO) {
128 int newoid = 0x100; /* minimum AUTO oid */
131 * Adjust based on highest oid in parent list
133 SLIST_FOREACH(p, parent, oid_link) {
134 if (newoid <= p->oid_number)
135 newoid = p->oid_number + 1;
137 oidp->oid_number = newoid;
141 * Insert the oid into the parent's list in order.
144 SLIST_FOREACH(p, parent, oid_link) {
145 if (oidp->oid_number < p->oid_number)
150 SLIST_INSERT_AFTER(q, oidp, oid_link);
152 SLIST_INSERT_HEAD(parent, oidp, oid_link);
156 sysctl_unregister_oid(struct sysctl_oid *oidp)
158 sysctl_lock(LK_EXCLUSIVE);
159 sysctl_unregister_oid_int(oidp);
164 sysctl_unregister_oid_int(struct sysctl_oid *oidp)
166 struct sysctl_oid *p;
168 if (oidp->oid_number == OID_AUTO)
169 panic("Trying to unregister OID_AUTO entry: %p", oidp);
171 SLIST_FOREACH(p, oidp->oid_parent, oid_link) {
174 SLIST_REMOVE(oidp->oid_parent, oidp, sysctl_oid, oid_link);
179 * This can happen when a module fails to register and is
180 * being unloaded afterwards. It should not be a panic()
183 kprintf("%s: failed to unregister sysctl\n", __func__);
186 /* Initialize a new context to keep track of dynamically added sysctls. */
188 sysctl_ctx_init(struct sysctl_ctx_list *c)
196 /* Free the context, and destroy all dynamic oids registered in this context */
198 sysctl_ctx_free(struct sysctl_ctx_list *clist)
200 struct sysctl_ctx_entry *e, *e1;
204 sysctl_ctx_lock(LK_EXCLUSIVE);
206 * First perform a "dry run" to check if it's ok to remove oids.
208 * XXX This algorithm is a hack. But I don't know any
209 * XXX better solution for now...
211 TAILQ_FOREACH(e, clist, link) {
212 error = sysctl_remove_oid(e->entry, 0, 0);
217 * Restore deregistered entries, either from the end,
218 * or from the place where error occured.
219 * e contains the entry that was not unregistered
222 e1 = TAILQ_PREV(e, sysctl_ctx_list, link);
224 e1 = TAILQ_LAST(clist, sysctl_ctx_list);
226 sysctl_register_oid(e1->entry);
227 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link);
233 /* Now really delete the entries */
234 e = TAILQ_FIRST(clist);
236 e1 = TAILQ_NEXT(e, link);
237 error = sysctl_remove_oid(e->entry, 1, 0);
239 panic("sysctl_remove_oid: corrupt tree, entry: %s",
241 kfree(e, M_SYSCTLOID);
248 /* Add an entry to the context */
249 struct sysctl_ctx_entry *
250 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
252 struct sysctl_ctx_entry *e;
254 if (clist == NULL || oidp == NULL)
256 e = kmalloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK);
258 sysctl_ctx_lock(LK_EXCLUSIVE);
259 TAILQ_INSERT_HEAD(clist, e, link);
264 /* Find an entry in the context */
265 struct sysctl_ctx_entry *
266 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
268 struct sysctl_ctx_entry *e;
270 if (clist == NULL || oidp == NULL)
273 sysctl_ctx_lock(LK_SHARED);
274 e = sysctl_ctx_entry_find_int(clist, oidp);
280 struct sysctl_ctx_entry *
281 sysctl_ctx_entry_find_int(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
283 struct sysctl_ctx_entry *e;
285 KKASSERT(clist != NULL && oidp != NULL);
287 for (e = TAILQ_FIRST(clist); e != NULL; e = TAILQ_NEXT(e, link)) {
296 * Delete an entry from the context.
297 * NOTE: this function doesn't free oidp! You have to remove it
298 * with sysctl_remove_oid().
301 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
303 struct sysctl_ctx_entry *e;
305 if (clist == NULL || oidp == NULL)
308 sysctl_ctx_lock(LK_EXCLUSIVE);
309 e = sysctl_ctx_entry_find_int(clist, oidp);
314 TAILQ_REMOVE(clist, e, link);
315 kfree(e, M_SYSCTLOID);
322 * Remove dynamically created sysctl trees.
323 * oidp - top of the tree to be removed
324 * del - if 0 - just deregister, otherwise free up entries as well
325 * recurse - if != 0 traverse the subtree to be deleted
328 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse)
330 struct sysctl_oid *p;
335 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) {
336 kprintf("can't remove non-dynamic nodes!\n");
339 sysctl_lock(LK_EXCLUSIVE | LK_CANRECURSE);
341 * WARNING: normal method to do this should be through
342 * sysctl_ctx_free(). Use recursing as the last resort
343 * method to purge your sysctl tree of leftovers...
344 * However, if some other code still references these nodes,
347 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
348 if (oidp->oid_refcnt == 1) {
349 SLIST_FOREACH(p, SYSCTL_CHILDREN(oidp), oid_link) {
354 error = sysctl_remove_oid(p, del, recurse);
361 kfree(SYSCTL_CHILDREN(oidp), M_SYSCTLOID);
364 if (oidp->oid_refcnt > 1 ) {
367 if (oidp->oid_refcnt == 0) {
368 kprintf("Warning: bad oid_refcnt=%u (%s)!\n",
369 oidp->oid_refcnt, oidp->oid_name);
373 sysctl_unregister_oid_int(oidp);
376 kfree(__DECONST(char *,oidp->oid_descr),
378 kfree(__DECONST(char *, oidp->oid_name), M_SYSCTLOID);
379 kfree(oidp, M_SYSCTLOID);
387 * Create new sysctls at run time.
388 * clist may point to a valid context initialized with sysctl_ctx_init().
391 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent,
392 int number, const char *name, int kind, void *arg1, int arg2,
393 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr)
395 struct sysctl_oid *oidp;
399 /* You have to hook up somewhere.. */
402 sysctl_lock(LK_EXCLUSIVE);
403 /* Check if the node already exists, otherwise create it */
404 oidp = sysctl_find_oidname(name, parent, 0);
406 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
408 /* Update the context */
410 sysctl_ctx_entry_add(clist, oidp);
414 kprintf("can't re-use a leaf (%s)!\n", name);
419 oidp = kmalloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK | M_ZERO);
420 oidp->oid_parent = parent;
421 SLIST_NEXT(oidp, oid_link) = NULL;
422 oidp->oid_number = number;
423 oidp->oid_refcnt = 1;
425 newname = kmalloc(len + 1, M_SYSCTLOID, M_WAITOK);
426 bcopy(name, newname, len + 1);
428 oidp->oid_name = newname;
429 oidp->oid_handler = handler;
430 oidp->oid_kind = CTLFLAG_DYN | kind;
431 if ((kind & CTLTYPE) == CTLTYPE_NODE) {
432 struct sysctl_oid_list *children;
434 /* Allocate space for children */
435 children = kmalloc(sizeof(*children), M_SYSCTLOID, M_WAITOK);
436 SYSCTL_SET_CHILDREN(oidp, children);
437 SLIST_INIT(children);
439 oidp->oid_arg1 = arg1;
440 oidp->oid_arg2 = arg2;
444 int len = strlen(descr) + 1;
445 oidp->oid_descr = kmalloc(len, M_SYSCTLOID, M_WAITOK);
447 strcpy((char *)(uintptr_t)(const void *)oidp->oid_descr, descr);
449 /* Update the context, if used */
451 sysctl_ctx_entry_add(clist, oidp);
452 /* Register this oid */
453 sysctl_register_oid_int(oidp);
459 * Register the kernel's oids on startup.
461 SET_DECLARE(sysctl_set, struct sysctl_oid);
464 sysctl_register_all(void *arg)
466 struct sysctl_oid **oidp;
468 lockinit(&sysctl_lkp, "sysctl", 0, 0);
469 lockinit(&sysctl_ctx_lkp, "sysctl ctx", 0, 0);
470 SET_FOREACH(oidp, sysctl_set)
471 sysctl_register_oid_int(*oidp);
474 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_ANY, sysctl_register_all, 0);
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.
487 * {0,0} kprintf the entire MIB-tree.
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.
495 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i)
498 struct sysctl_oid *oidp;
500 sysctl_lock(LK_SHARED);
501 SLIST_FOREACH(oidp, l, oid_link) {
506 kprintf("%d %s ", oidp->oid_number, oidp->oid_name);
509 oidp->oid_kind & CTLFLAG_RD ? 'R':' ',
510 oidp->oid_kind & CTLFLAG_WR ? 'W':' ');
512 if (oidp->oid_handler)
513 kprintf(" *Handler");
515 switch (oidp->oid_kind & CTLTYPE) {
518 if (!oidp->oid_handler) {
519 sysctl_sysctl_debug_dump_node(
520 oidp->oid_arg1, i+2);
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");
535 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS)
539 error = suser(req->td);
542 sysctl_sysctl_debug_dump_node(&sysctl__children, 0);
546 SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD,
547 0, 0, sysctl_sysctl_debug, "-", "");
550 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS)
552 int *name = (int *) arg1;
553 u_int namelen = arg2;
555 struct sysctl_oid *oid;
556 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2;
559 sysctl_lock(LK_SHARED);
562 ksnprintf(buf,sizeof(buf),"%d",*name);
564 error = SYSCTL_OUT(req, ".", 1);
566 error = SYSCTL_OUT(req, buf, strlen(buf));
576 SLIST_FOREACH(oid, lsp, oid_link) {
577 if (oid->oid_number != *name)
581 error = SYSCTL_OUT(req, ".", 1);
583 error = SYSCTL_OUT(req, oid->oid_name,
584 strlen(oid->oid_name));
593 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE)
596 if (oid->oid_handler)
599 lsp2 = (struct sysctl_oid_list *)oid->oid_arg1;
605 return (SYSCTL_OUT(req, "", 1));
608 SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD, sysctl_sysctl_name, "");
611 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen,
612 int *next, int *len, int level, struct sysctl_oid **oidpp)
614 struct sysctl_oid *oidp;
617 sysctl_lock(LK_SHARED);
618 SLIST_FOREACH(oidp, lsp, oid_link) {
619 *next = oidp->oid_number;
623 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) {
627 if (oidp->oid_handler) {
628 /* We really should call the handler here...*/
632 lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
633 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1,
634 len, level+1, oidpp)) {
641 if (oidp->oid_number < *name)
644 if (oidp->oid_number > *name) {
645 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) {
649 if (oidp->oid_handler) {
653 lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
654 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1,
655 next+1, len, level+1, oidpp)) {
661 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
664 if (oidp->oid_handler)
667 lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
668 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1,
669 len, level+1, oidpp)) {
684 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS)
686 int *name = (int *) arg1;
687 u_int namelen = arg2;
689 struct sysctl_oid *oid;
690 struct sysctl_oid_list *lsp = &sysctl__children;
691 int newoid[CTL_MAXNAME];
693 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid);
696 error = SYSCTL_OUT(req, newoid, j * sizeof (int));
700 SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD, sysctl_sysctl_next, "");
703 name2oid (char *name, int *oid, int *len, struct sysctl_oid **oidpp)
706 struct sysctl_oid *oidp;
707 struct sysctl_oid_list *lsp = &sysctl__children;
713 p = name + strlen(name) - 1 ;
719 for (p = name; *p && *p != '.'; p++)
725 sysctl_lock(LK_SHARED);
726 oidp = SLIST_FIRST(lsp);
728 while (oidp && *len < CTL_MAXNAME) {
729 if (strcmp(name, oidp->oid_name)) {
730 oidp = SLIST_NEXT(oidp, oid_link);
733 *oid++ = oidp->oid_number;
743 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
746 if (oidp->oid_handler)
749 lsp = (struct sysctl_oid_list *)oidp->oid_arg1;
750 oidp = SLIST_FIRST(lsp);
752 for (p = name; *p && *p != '.'; p++)
763 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS)
766 int error, oid[CTL_MAXNAME], len;
767 struct sysctl_oid *op = 0;
771 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */
772 return (ENAMETOOLONG);
774 p = kmalloc(req->newlen+1, M_SYSCTL, M_WAITOK);
776 error = SYSCTL_IN(req, p, req->newlen);
782 p [req->newlen] = '\0';
784 error = name2oid(p, oid, &len, &op);
791 error = SYSCTL_OUT(req, oid, len * sizeof *oid);
795 SYSCTL_PROC(_sysctl, 3, name2oid, CTLFLAG_RW|CTLFLAG_ANYBODY, 0, 0,
796 sysctl_sysctl_name2oid, "I", "");
799 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS)
801 struct sysctl_oid *oid;
804 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
810 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind));
813 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1);
818 SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD, sysctl_sysctl_oidfmt, "");
821 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS)
823 struct sysctl_oid *oid;
826 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
832 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1);
836 SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD, sysctl_sysctl_oiddescr, "");
839 * Default "handler" functions.
843 * Handle an int, signed or unsigned.
845 * a variable: point arg1 at it.
846 * a constant: pass it in arg2.
850 sysctl_handle_int(SYSCTL_HANDLER_ARGS)
855 error = SYSCTL_OUT(req, arg1, sizeof(int));
857 error = SYSCTL_OUT(req, &arg2, sizeof(int));
859 if (error || !req->newptr)
865 error = SYSCTL_IN(req, arg1, sizeof(int));
870 * Handle a long, signed or unsigned. arg1 points to it.
874 sysctl_handle_long(SYSCTL_HANDLER_ARGS)
880 error = SYSCTL_OUT(req, arg1, sizeof(long));
882 if (error || !req->newptr)
885 error = SYSCTL_IN(req, arg1, sizeof(long));
890 * Handle a quad, signed or unsigned. arg1 points to it.
894 sysctl_handle_quad(SYSCTL_HANDLER_ARGS)
900 error = SYSCTL_OUT(req, arg1, sizeof(quad_t));
902 if (error || !req->newptr)
905 error = SYSCTL_IN(req, arg1, sizeof(quad_t));
910 * Handle our generic '\0' terminated 'C' string.
912 * a variable string: point arg1 at it, arg2 is max length.
913 * a constant string: point arg1 at it, arg2 is zero.
917 sysctl_handle_string(SYSCTL_HANDLER_ARGS)
921 error = SYSCTL_OUT(req, arg1, strlen((char *)arg1)+1);
923 if (error || !req->newptr)
926 if ((req->newlen - req->newidx) >= arg2) {
929 arg2 = (req->newlen - req->newidx);
930 error = SYSCTL_IN(req, arg1, arg2);
931 ((char *)arg1)[arg2] = '\0';
938 * Handle any kind of opaque data.
939 * arg1 points to it, arg2 is the size.
943 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS)
947 error = SYSCTL_OUT(req, arg1, arg2);
949 if (error || !req->newptr)
952 error = SYSCTL_IN(req, arg1, arg2);
958 * Transfer functions to/from kernel space.
959 * XXX: rather untested at this point
962 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l)
968 if (i > req->oldlen - req->oldidx)
969 i = req->oldlen - req->oldidx;
971 bcopy(p, (char *)req->oldptr + req->oldidx, i);
974 if (req->oldptr && i != l)
980 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l)
985 if (req->newlen - req->newidx < l)
987 bcopy((char *)req->newptr + req->newidx, p, l);
993 kernel_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval)
996 struct sysctl_req req;
998 bzero(&req, sizeof req);
1003 req.oldlen = *oldlenp;
1011 req.newlen = newlen;
1015 req.oldfunc = sysctl_old_kernel;
1016 req.newfunc = sysctl_new_kernel;
1019 sysctl_lock(LK_SHARED);
1021 error = sysctl_root(0, name, namelen, &req);
1024 vsunlock(req.oldptr, req.oldlen);
1028 if (error && error != ENOMEM)
1032 if (req.oldptr && req.oldidx > req.oldlen)
1033 *retval = req.oldlen;
1035 *retval = req.oldidx;
1041 kernel_sysctlbyname(char *name, void *old, size_t *oldlenp,
1042 void *new, size_t newlen, size_t *retval)
1044 int oid[CTL_MAXNAME];
1045 size_t oidlen, plen;
1048 oid[0] = 0; /* sysctl internal magic */
1049 oid[1] = 3; /* name2oid */
1050 oidlen = sizeof(oid);
1052 error = kernel_sysctl(oid, 2, oid, &oidlen, (void *)name,
1053 strlen(name), &plen);
1057 error = kernel_sysctl(oid, plen / sizeof(int), old, oldlenp,
1058 new, newlen, retval);
1063 * Transfer function to/from user space.
1066 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l)
1071 if (req->lock == 1 && req->oldptr) {
1072 vslock(req->oldptr, req->oldlen);
1077 if (i > req->oldlen - req->oldidx)
1078 i = req->oldlen - req->oldidx;
1080 error = copyout(p, (char *)req->oldptr + req->oldidx,
1086 if (req->oldptr && i < l)
1092 sysctl_new_user(struct sysctl_req *req, void *p, size_t l)
1098 if (req->newlen - req->newidx < l)
1100 error = copyin((char *)req->newptr + req->newidx, p, l);
1106 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid,
1107 int *nindx, struct sysctl_req *req)
1109 struct sysctl_oid *oid;
1112 sysctl_lock(LK_SHARED);
1113 oid = SLIST_FIRST(&sysctl__children);
1115 while (oid && indx < CTL_MAXNAME) {
1116 if (oid->oid_number == name[indx]) {
1118 if (oid->oid_kind & CTLFLAG_NOLOCK)
1120 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
1121 if (oid->oid_handler != NULL ||
1130 (struct sysctl_oid_list *)oid->oid_arg1);
1131 } else if (indx == namelen) {
1142 oid = SLIST_NEXT(oid, oid_link);
1150 * Traverse our tree, and find the right node, execute whatever it points
1151 * to, and return the resulting error code.
1155 sysctl_root(SYSCTL_HANDLER_ARGS)
1157 struct thread *td = req->td;
1158 struct proc *p = td ? td->td_proc : NULL;
1159 struct sysctl_oid *oid;
1162 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req);
1166 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
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.
1172 if (oid->oid_handler == NULL)
1176 /* If writing isn't allowed */
1177 if (req->newptr && (!(oid->oid_kind & CTLFLAG_WR) ||
1178 ((oid->oid_kind & CTLFLAG_SECURE) && securelevel > 0)))
1181 /* Most likely only root can write */
1182 if (!(oid->oid_kind & CTLFLAG_ANYBODY) && req->newptr && p &&
1183 (error = suser_cred(p->p_ucred,
1184 (oid->oid_kind & CTLFLAG_PRISON) ? PRISON_ROOT : 0)))
1187 if (!oid->oid_handler)
1190 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE)
1191 error = oid->oid_handler(oid, (int *)arg1 + indx, arg2 - indx,
1194 error = oid->oid_handler(oid, oid->oid_arg1, oid->oid_arg2,
1200 sys___sysctl(struct sysctl_args *uap)
1202 int error, i, name[CTL_MAXNAME];
1205 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2)
1208 error = copyin(uap->name, &name, uap->namelen * sizeof(int));
1212 error = userland_sysctl(name, uap->namelen,
1213 uap->old, uap->oldlenp, 0,
1214 uap->new, uap->newlen, &j);
1215 if (error && error != ENOMEM)
1218 i = copyout(&j, uap->oldlenp, sizeof(j));
1226 * This is used from various compatibility syscalls too. That's why name
1227 * must be in kernel space.
1230 userland_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval)
1233 struct sysctl_req req, req2;
1235 bzero(&req, sizeof req);
1239 req.oldlen = *oldlenp;
1241 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp));
1248 if (!useracc(old, req.oldlen, VM_PROT_WRITE))
1254 if (!useracc(new, req.newlen, VM_PROT_READ))
1256 req.newlen = newlen;
1260 req.oldfunc = sysctl_old_user;
1261 req.newfunc = sysctl_new_user;
1265 sysctl_lock(LK_SHARED);
1269 error = sysctl_root(0, name, namelen, &req2);
1270 } while (error == EAGAIN);
1274 vsunlock(req.oldptr, req.oldlen);
1278 if (error && error != ENOMEM)
1282 if (req.oldptr && req.oldidx > req.oldlen)
1283 *retval = req.oldlen;
1285 *retval = req.oldidx;
1291 sysctl_lock(int flag)
1293 lockmgr(&sysctl_lkp, flag);
1299 lockmgr(&sysctl_lkp, LK_RELEASE);
1303 sysctl_ctx_lock(int flag)
1305 lockmgr(&sysctl_ctx_lkp, flag);
1309 sysctl_ctx_unlock(void)
1311 lockmgr(&sysctl_ctx_lkp, LK_RELEASE);