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 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94
36 */
37
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD: releng/11.0/sys/kern/kern_sysctl.c 300718 2016-05-26 08:41:55Z hselasky $");
40
41 #include "opt_capsicum.h"
42 #include "opt_compat.h"
43 #include "opt_ktrace.h"
44
45 #include <sys/param.h>
46 #include <sys/fail.h>
47 #include <sys/systm.h>
48 #include <sys/capsicum.h>
49 #include <sys/kernel.h>
50 #include <sys/sysctl.h>
51 #include <sys/malloc.h>
52 #include <sys/priv.h>
53 #include <sys/proc.h>
54 #include <sys/jail.h>
55 #include <sys/lock.h>
56 #include <sys/mutex.h>
57 #include <sys/rmlock.h>
58 #include <sys/sbuf.h>
59 #include <sys/sx.h>
60 #include <sys/sysproto.h>
61 #include <sys/uio.h>
62 #ifdef KTRACE
63 #include <sys/ktrace.h>
64 #endif
65
66 #include <net/vnet.h>
67
68 #include <security/mac/mac_framework.h>
69
70 #include <vm/vm.h>
71 #include <vm/vm_extern.h>
72
73 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic");
74 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids");
75 static MALLOC_DEFINE(M_SYSCTLTMP, "sysctltmp", "sysctl temp output buffer");
76
77 /*
78 * The sysctllock protects the MIB tree. It also protects sysctl
79 * contexts used with dynamic sysctls. The sysctl_register_oid() and
80 * sysctl_unregister_oid() routines require the sysctllock to already
81 * be held, so the sysctl_wlock() and sysctl_wunlock() routines are
82 * provided for the few places in the kernel which need to use that
83 * API rather than using the dynamic API. Use of the dynamic API is
84 * strongly encouraged for most code.
85 *
86 * The sysctlmemlock is used to limit the amount of user memory wired for
87 * sysctl requests. This is implemented by serializing any userland
88 * sysctl requests larger than a single page via an exclusive lock.
89 */
90 static struct rmlock sysctllock;
91 static struct sx sysctlmemlock;
92
93 #define SYSCTL_WLOCK() rm_wlock(&sysctllock)
94 #define SYSCTL_WUNLOCK() rm_wunlock(&sysctllock)
95 #define SYSCTL_RLOCK(tracker) rm_rlock(&sysctllock, (tracker))
96 #define SYSCTL_RUNLOCK(tracker) rm_runlock(&sysctllock, (tracker))
97 #define SYSCTL_WLOCKED() rm_wowned(&sysctllock)
98 #define SYSCTL_ASSERT_LOCKED() rm_assert(&sysctllock, RA_LOCKED)
99 #define SYSCTL_ASSERT_WLOCKED() rm_assert(&sysctllock, RA_WLOCKED)
100 #define SYSCTL_ASSERT_RLOCKED() rm_assert(&sysctllock, RA_RLOCKED)
101 #define SYSCTL_INIT() rm_init_flags(&sysctllock, "sysctl lock", \
102 RM_SLEEPABLE)
103 #define SYSCTL_SLEEP(ch, wmesg, timo) \
104 rm_sleep(ch, &sysctllock, 0, wmesg, timo)
105
106 static int sysctl_root(SYSCTL_HANDLER_ARGS);
107
108 /* Root list */
109 struct sysctl_oid_list sysctl__children = SLIST_HEAD_INITIALIZER(&sysctl__children);
110
111 static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del,
112 int recurse);
113 static int sysctl_old_kernel(struct sysctl_req *, const void *, size_t);
114 static int sysctl_new_kernel(struct sysctl_req *, void *, size_t);
115
116 static struct sysctl_oid *
117 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list)
118 {
119 struct sysctl_oid *oidp;
120
121 SYSCTL_ASSERT_LOCKED();
122 SLIST_FOREACH(oidp, list, oid_link) {
123 if (strcmp(oidp->oid_name, name) == 0) {
124 return (oidp);
125 }
126 }
127 return (NULL);
128 }
129
130 /*
131 * Initialization of the MIB tree.
132 *
133 * Order by number in each list.
134 */
135 void
136 sysctl_wlock(void)
137 {
138
139 SYSCTL_WLOCK();
140 }
141
142 void
143 sysctl_wunlock(void)
144 {
145
146 SYSCTL_WUNLOCK();
147 }
148
149 static int
150 sysctl_root_handler_locked(struct sysctl_oid *oid, void *arg1, intmax_t arg2,
151 struct sysctl_req *req, struct rm_priotracker *tracker)
152 {
153 int error;
154
155 if (oid->oid_kind & CTLFLAG_DYN)
156 atomic_add_int(&oid->oid_running, 1);
157
158 if (tracker != NULL)
159 SYSCTL_RUNLOCK(tracker);
160 else
161 SYSCTL_WUNLOCK();
162
163 if (!(oid->oid_kind & CTLFLAG_MPSAFE))
164 mtx_lock(&Giant);
165 error = oid->oid_handler(oid, arg1, arg2, req);
166 if (!(oid->oid_kind & CTLFLAG_MPSAFE))
167 mtx_unlock(&Giant);
168
169 KFAIL_POINT_ERROR(_debug_fail_point, sysctl_running, error);
170
171 if (tracker != NULL)
172 SYSCTL_RLOCK(tracker);
173 else
174 SYSCTL_WLOCK();
175
176 if (oid->oid_kind & CTLFLAG_DYN) {
177 if (atomic_fetchadd_int(&oid->oid_running, -1) == 1 &&
178 (oid->oid_kind & CTLFLAG_DYING) != 0)
179 wakeup(&oid->oid_running);
180 }
181
182 return (error);
183 }
184
185 static void
186 sysctl_load_tunable_by_oid_locked(struct sysctl_oid *oidp)
187 {
188 struct sysctl_req req;
189 struct sysctl_oid *curr;
190 char *penv = NULL;
191 char path[64];
192 ssize_t rem = sizeof(path);
193 ssize_t len;
194 uint8_t val_8;
195 uint16_t val_16;
196 uint32_t val_32;
197 int val_int;
198 long val_long;
199 int64_t val_64;
200 quad_t val_quad;
201 int error;
202
203 path[--rem] = 0;
204
205 for (curr = oidp; curr != NULL; curr = SYSCTL_PARENT(curr)) {
206 len = strlen(curr->oid_name);
207 rem -= len;
208 if (curr != oidp)
209 rem -= 1;
210 if (rem < 0) {
211 printf("OID path exceeds %d bytes\n", (int)sizeof(path));
212 return;
213 }
214 memcpy(path + rem, curr->oid_name, len);
215 if (curr != oidp)
216 path[rem + len] = '.';
217 }
218
219 memset(&req, 0, sizeof(req));
220
221 req.td = curthread;
222 req.oldfunc = sysctl_old_kernel;
223 req.newfunc = sysctl_new_kernel;
224 req.lock = REQ_UNWIRED;
225
226 switch (oidp->oid_kind & CTLTYPE) {
227 case CTLTYPE_INT:
228 if (getenv_int(path + rem, &val_int) == 0)
229 return;
230 req.newlen = sizeof(val_int);
231 req.newptr = &val_int;
232 break;
233 case CTLTYPE_UINT:
234 if (getenv_uint(path + rem, (unsigned int *)&val_int) == 0)
235 return;
236 req.newlen = sizeof(val_int);
237 req.newptr = &val_int;
238 break;
239 case CTLTYPE_LONG:
240 if (getenv_long(path + rem, &val_long) == 0)
241 return;
242 req.newlen = sizeof(val_long);
243 req.newptr = &val_long;
244 break;
245 case CTLTYPE_ULONG:
246 if (getenv_ulong(path + rem, (unsigned long *)&val_long) == 0)
247 return;
248 req.newlen = sizeof(val_long);
249 req.newptr = &val_long;
250 break;
251 case CTLTYPE_S8:
252 if (getenv_int(path + rem, &val_int) == 0)
253 return;
254 val_8 = val_int;
255 req.newlen = sizeof(val_8);
256 req.newptr = &val_8;
257 break;
258 case CTLTYPE_S16:
259 if (getenv_int(path + rem, &val_int) == 0)
260 return;
261 val_16 = val_int;
262 req.newlen = sizeof(val_16);
263 req.newptr = &val_16;
264 break;
265 case CTLTYPE_S32:
266 if (getenv_long(path + rem, &val_long) == 0)
267 return;
268 val_32 = val_long;
269 req.newlen = sizeof(val_32);
270 req.newptr = &val_32;
271 break;
272 case CTLTYPE_S64:
273 if (getenv_quad(path + rem, &val_quad) == 0)
274 return;
275 val_64 = val_quad;
276 req.newlen = sizeof(val_64);
277 req.newptr = &val_64;
278 break;
279 case CTLTYPE_U8:
280 if (getenv_uint(path + rem, (unsigned int *)&val_int) == 0)
281 return;
282 val_8 = val_int;
283 req.newlen = sizeof(val_8);
284 req.newptr = &val_8;
285 break;
286 case CTLTYPE_U16:
287 if (getenv_uint(path + rem, (unsigned int *)&val_int) == 0)
288 return;
289 val_16 = val_int;
290 req.newlen = sizeof(val_16);
291 req.newptr = &val_16;
292 break;
293 case CTLTYPE_U32:
294 if (getenv_ulong(path + rem, (unsigned long *)&val_long) == 0)
295 return;
296 val_32 = val_long;
297 req.newlen = sizeof(val_32);
298 req.newptr = &val_32;
299 break;
300 case CTLTYPE_U64:
301 /* XXX there is no getenv_uquad() */
302 if (getenv_quad(path + rem, &val_quad) == 0)
303 return;
304 val_64 = val_quad;
305 req.newlen = sizeof(val_64);
306 req.newptr = &val_64;
307 break;
308 case CTLTYPE_STRING:
309 penv = kern_getenv(path + rem);
310 if (penv == NULL)
311 return;
312 req.newlen = strlen(penv);
313 req.newptr = penv;
314 break;
315 default:
316 return;
317 }
318 error = sysctl_root_handler_locked(oidp, oidp->oid_arg1,
319 oidp->oid_arg2, &req, NULL);
320 if (error != 0)
321 printf("Setting sysctl %s failed: %d\n", path + rem, error);
322 if (penv != NULL)
323 freeenv(penv);
324 }
325
326 void
327 sysctl_register_oid(struct sysctl_oid *oidp)
328 {
329 struct sysctl_oid_list *parent = oidp->oid_parent;
330 struct sysctl_oid *p;
331 struct sysctl_oid *q;
332 int oid_number;
333 int timeout = 2;
334
335 /*
336 * First check if another oid with the same name already
337 * exists in the parent's list.
338 */
339 SYSCTL_ASSERT_WLOCKED();
340 p = sysctl_find_oidname(oidp->oid_name, parent);
341 if (p != NULL) {
342 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
343 p->oid_refcnt++;
344 return;
345 } else {
346 printf("can't re-use a leaf (%s)!\n", p->oid_name);
347 return;
348 }
349 }
350 /* get current OID number */
351 oid_number = oidp->oid_number;
352
353 #if (OID_AUTO >= 0)
354 #error "OID_AUTO is expected to be a negative value"
355 #endif
356 /*
357 * Any negative OID number qualifies as OID_AUTO. Valid OID
358 * numbers should always be positive.
359 *
360 * NOTE: DO NOT change the starting value here, change it in
361 * <sys/sysctl.h>, and make sure it is at least 256 to
362 * accommodate e.g. net.inet.raw as a static sysctl node.
363 */
364 if (oid_number < 0) {
365 static int newoid;
366
367 /*
368 * By decrementing the next OID number we spend less
369 * time inserting the OIDs into a sorted list.
370 */
371 if (--newoid < CTL_AUTO_START)
372 newoid = 0x7fffffff;
373
374 oid_number = newoid;
375 }
376
377 /*
378 * Insert the OID into the parent's list sorted by OID number.
379 */
380 retry:
381 q = NULL;
382 SLIST_FOREACH(p, parent, oid_link) {
383 /* check if the current OID number is in use */
384 if (oid_number == p->oid_number) {
385 /* get the next valid OID number */
386 if (oid_number < CTL_AUTO_START ||
387 oid_number == 0x7fffffff) {
388 /* wraparound - restart */
389 oid_number = CTL_AUTO_START;
390 /* don't loop forever */
391 if (!timeout--)
392 panic("sysctl: Out of OID numbers\n");
393 goto retry;
394 } else {
395 oid_number++;
396 }
397 } else if (oid_number < p->oid_number)
398 break;
399 q = p;
400 }
401 /* check for non-auto OID number collision */
402 if (oidp->oid_number >= 0 && oidp->oid_number < CTL_AUTO_START &&
403 oid_number >= CTL_AUTO_START) {
404 printf("sysctl: OID number(%d) is already in use for '%s'\n",
405 oidp->oid_number, oidp->oid_name);
406 }
407 /* update the OID number, if any */
408 oidp->oid_number = oid_number;
409 if (q != NULL)
410 SLIST_INSERT_AFTER(q, oidp, oid_link);
411 else
412 SLIST_INSERT_HEAD(parent, oidp, oid_link);
413
414 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE &&
415 #ifdef VIMAGE
416 (oidp->oid_kind & CTLFLAG_VNET) == 0 &&
417 #endif
418 (oidp->oid_kind & CTLFLAG_TUN) != 0 &&
419 (oidp->oid_kind & CTLFLAG_NOFETCH) == 0) {
420 /* only fetch value once */
421 oidp->oid_kind |= CTLFLAG_NOFETCH;
422 /* try to fetch value from kernel environment */
423 sysctl_load_tunable_by_oid_locked(oidp);
424 }
425 }
426
427 void
428 sysctl_unregister_oid(struct sysctl_oid *oidp)
429 {
430 struct sysctl_oid *p;
431 int error;
432
433 SYSCTL_ASSERT_WLOCKED();
434 error = ENOENT;
435 if (oidp->oid_number == OID_AUTO) {
436 error = EINVAL;
437 } else {
438 SLIST_FOREACH(p, oidp->oid_parent, oid_link) {
439 if (p == oidp) {
440 SLIST_REMOVE(oidp->oid_parent, oidp,
441 sysctl_oid, oid_link);
442 error = 0;
443 break;
444 }
445 }
446 }
447
448 /*
449 * This can happen when a module fails to register and is
450 * being unloaded afterwards. It should not be a panic()
451 * for normal use.
452 */
453 if (error)
454 printf("%s: failed to unregister sysctl\n", __func__);
455 }
456
457 /* Initialize a new context to keep track of dynamically added sysctls. */
458 int
459 sysctl_ctx_init(struct sysctl_ctx_list *c)
460 {
461
462 if (c == NULL) {
463 return (EINVAL);
464 }
465
466 /*
467 * No locking here, the caller is responsible for not adding
468 * new nodes to a context until after this function has
469 * returned.
470 */
471 TAILQ_INIT(c);
472 return (0);
473 }
474
475 /* Free the context, and destroy all dynamic oids registered in this context */
476 int
477 sysctl_ctx_free(struct sysctl_ctx_list *clist)
478 {
479 struct sysctl_ctx_entry *e, *e1;
480 int error;
481
482 error = 0;
483 /*
484 * First perform a "dry run" to check if it's ok to remove oids.
485 * XXX FIXME
486 * XXX This algorithm is a hack. But I don't know any
487 * XXX better solution for now...
488 */
489 SYSCTL_WLOCK();
490 TAILQ_FOREACH(e, clist, link) {
491 error = sysctl_remove_oid_locked(e->entry, 0, 0);
492 if (error)
493 break;
494 }
495 /*
496 * Restore deregistered entries, either from the end,
497 * or from the place where error occurred.
498 * e contains the entry that was not unregistered
499 */
500 if (error)
501 e1 = TAILQ_PREV(e, sysctl_ctx_list, link);
502 else
503 e1 = TAILQ_LAST(clist, sysctl_ctx_list);
504 while (e1 != NULL) {
505 sysctl_register_oid(e1->entry);
506 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link);
507 }
508 if (error) {
509 SYSCTL_WUNLOCK();
510 return(EBUSY);
511 }
512 /* Now really delete the entries */
513 e = TAILQ_FIRST(clist);
514 while (e != NULL) {
515 e1 = TAILQ_NEXT(e, link);
516 error = sysctl_remove_oid_locked(e->entry, 1, 0);
517 if (error)
518 panic("sysctl_remove_oid: corrupt tree, entry: %s",
519 e->entry->oid_name);
520 free(e, M_SYSCTLOID);
521 e = e1;
522 }
523 SYSCTL_WUNLOCK();
524 return (error);
525 }
526
527 /* Add an entry to the context */
528 struct sysctl_ctx_entry *
529 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
530 {
531 struct sysctl_ctx_entry *e;
532
533 SYSCTL_ASSERT_WLOCKED();
534 if (clist == NULL || oidp == NULL)
535 return(NULL);
536 e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK);
537 e->entry = oidp;
538 TAILQ_INSERT_HEAD(clist, e, link);
539 return (e);
540 }
541
542 /* Find an entry in the context */
543 struct sysctl_ctx_entry *
544 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
545 {
546 struct sysctl_ctx_entry *e;
547
548 SYSCTL_ASSERT_WLOCKED();
549 if (clist == NULL || oidp == NULL)
550 return(NULL);
551 TAILQ_FOREACH(e, clist, link) {
552 if(e->entry == oidp)
553 return(e);
554 }
555 return (e);
556 }
557
558 /*
559 * Delete an entry from the context.
560 * NOTE: this function doesn't free oidp! You have to remove it
561 * with sysctl_remove_oid().
562 */
563 int
564 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
565 {
566 struct sysctl_ctx_entry *e;
567
568 if (clist == NULL || oidp == NULL)
569 return (EINVAL);
570 SYSCTL_WLOCK();
571 e = sysctl_ctx_entry_find(clist, oidp);
572 if (e != NULL) {
573 TAILQ_REMOVE(clist, e, link);
574 SYSCTL_WUNLOCK();
575 free(e, M_SYSCTLOID);
576 return (0);
577 } else {
578 SYSCTL_WUNLOCK();
579 return (ENOENT);
580 }
581 }
582
583 /*
584 * Remove dynamically created sysctl trees.
585 * oidp - top of the tree to be removed
586 * del - if 0 - just deregister, otherwise free up entries as well
587 * recurse - if != 0 traverse the subtree to be deleted
588 */
589 int
590 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse)
591 {
592 int error;
593
594 SYSCTL_WLOCK();
595 error = sysctl_remove_oid_locked(oidp, del, recurse);
596 SYSCTL_WUNLOCK();
597 return (error);
598 }
599
600 int
601 sysctl_remove_name(struct sysctl_oid *parent, const char *name,
602 int del, int recurse)
603 {
604 struct sysctl_oid *p, *tmp;
605 int error;
606
607 error = ENOENT;
608 SYSCTL_WLOCK();
609 SLIST_FOREACH_SAFE(p, SYSCTL_CHILDREN(parent), oid_link, tmp) {
610 if (strcmp(p->oid_name, name) == 0) {
611 error = sysctl_remove_oid_locked(p, del, recurse);
612 break;
613 }
614 }
615 SYSCTL_WUNLOCK();
616
617 return (error);
618 }
619
620
621 static int
622 sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse)
623 {
624 struct sysctl_oid *p, *tmp;
625 int error;
626
627 SYSCTL_ASSERT_WLOCKED();
628 if (oidp == NULL)
629 return(EINVAL);
630 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) {
631 printf("can't remove non-dynamic nodes!\n");
632 return (EINVAL);
633 }
634 /*
635 * WARNING: normal method to do this should be through
636 * sysctl_ctx_free(). Use recursing as the last resort
637 * method to purge your sysctl tree of leftovers...
638 * However, if some other code still references these nodes,
639 * it will panic.
640 */
641 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
642 if (oidp->oid_refcnt == 1) {
643 SLIST_FOREACH_SAFE(p,
644 SYSCTL_CHILDREN(oidp), oid_link, tmp) {
645 if (!recurse) {
646 printf("Warning: failed attempt to "
647 "remove oid %s with child %s\n",
648 oidp->oid_name, p->oid_name);
649 return (ENOTEMPTY);
650 }
651 error = sysctl_remove_oid_locked(p, del,
652 recurse);
653 if (error)
654 return (error);
655 }
656 }
657 }
658 if (oidp->oid_refcnt > 1 ) {
659 oidp->oid_refcnt--;
660 } else {
661 if (oidp->oid_refcnt == 0) {
662 printf("Warning: bad oid_refcnt=%u (%s)!\n",
663 oidp->oid_refcnt, oidp->oid_name);
664 return (EINVAL);
665 }
666 sysctl_unregister_oid(oidp);
667 if (del) {
668 /*
669 * Wait for all threads running the handler to drain.
670 * This preserves the previous behavior when the
671 * sysctl lock was held across a handler invocation,
672 * and is necessary for module unload correctness.
673 */
674 while (oidp->oid_running > 0) {
675 oidp->oid_kind |= CTLFLAG_DYING;
676 SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0);
677 }
678 if (oidp->oid_descr)
679 free(__DECONST(char *, oidp->oid_descr),
680 M_SYSCTLOID);
681 free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID);
682 free(oidp, M_SYSCTLOID);
683 }
684 }
685 return (0);
686 }
687 /*
688 * Create new sysctls at run time.
689 * clist may point to a valid context initialized with sysctl_ctx_init().
690 */
691 struct sysctl_oid *
692 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent,
693 int number, const char *name, int kind, void *arg1, intmax_t arg2,
694 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr)
695 {
696 struct sysctl_oid *oidp;
697
698 /* You have to hook up somewhere.. */
699 if (parent == NULL)
700 return(NULL);
701 /* Check if the node already exists, otherwise create it */
702 SYSCTL_WLOCK();
703 oidp = sysctl_find_oidname(name, parent);
704 if (oidp != NULL) {
705 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
706 oidp->oid_refcnt++;
707 /* Update the context */
708 if (clist != NULL)
709 sysctl_ctx_entry_add(clist, oidp);
710 SYSCTL_WUNLOCK();
711 return (oidp);
712 } else {
713 SYSCTL_WUNLOCK();
714 printf("can't re-use a leaf (%s)!\n", name);
715 return (NULL);
716 }
717 }
718 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO);
719 oidp->oid_parent = parent;
720 SLIST_INIT(&oidp->oid_children);
721 oidp->oid_number = number;
722 oidp->oid_refcnt = 1;
723 oidp->oid_name = strdup(name, M_SYSCTLOID);
724 oidp->oid_handler = handler;
725 oidp->oid_kind = CTLFLAG_DYN | kind;
726 oidp->oid_arg1 = arg1;
727 oidp->oid_arg2 = arg2;
728 oidp->oid_fmt = fmt;
729 if (descr != NULL)
730 oidp->oid_descr = strdup(descr, M_SYSCTLOID);
731 /* Update the context, if used */
732 if (clist != NULL)
733 sysctl_ctx_entry_add(clist, oidp);
734 /* Register this oid */
735 sysctl_register_oid(oidp);
736 SYSCTL_WUNLOCK();
737 return (oidp);
738 }
739
740 /*
741 * Rename an existing oid.
742 */
743 void
744 sysctl_rename_oid(struct sysctl_oid *oidp, const char *name)
745 {
746 char *newname;
747 char *oldname;
748
749 newname = strdup(name, M_SYSCTLOID);
750 SYSCTL_WLOCK();
751 oldname = __DECONST(char *, oidp->oid_name);
752 oidp->oid_name = newname;
753 SYSCTL_WUNLOCK();
754 free(oldname, M_SYSCTLOID);
755 }
756
757 /*
758 * Reparent an existing oid.
759 */
760 int
761 sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent)
762 {
763 struct sysctl_oid *oidp;
764
765 SYSCTL_WLOCK();
766 if (oid->oid_parent == parent) {
767 SYSCTL_WUNLOCK();
768 return (0);
769 }
770 oidp = sysctl_find_oidname(oid->oid_name, parent);
771 if (oidp != NULL) {
772 SYSCTL_WUNLOCK();
773 return (EEXIST);
774 }
775 sysctl_unregister_oid(oid);
776 oid->oid_parent = parent;
777 oid->oid_number = OID_AUTO;
778 sysctl_register_oid(oid);
779 SYSCTL_WUNLOCK();
780 return (0);
781 }
782
783 /*
784 * Register the kernel's oids on startup.
785 */
786 SET_DECLARE(sysctl_set, struct sysctl_oid);
787
788 static void
789 sysctl_register_all(void *arg)
790 {
791 struct sysctl_oid **oidp;
792
793 sx_init(&sysctlmemlock, "sysctl mem");
794 SYSCTL_INIT();
795 SYSCTL_WLOCK();
796 SET_FOREACH(oidp, sysctl_set)
797 sysctl_register_oid(*oidp);
798 SYSCTL_WUNLOCK();
799 }
800 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, 0);
801
802 /*
803 * "Staff-functions"
804 *
805 * These functions implement a presently undocumented interface
806 * used by the sysctl program to walk the tree, and get the type
807 * so it can print the value.
808 * This interface is under work and consideration, and should probably
809 * be killed with a big axe by the first person who can find the time.
810 * (be aware though, that the proper interface isn't as obvious as it
811 * may seem, there are various conflicting requirements.
812 *
813 * {0,0} printf the entire MIB-tree.
814 * {0,1,...} return the name of the "..." OID.
815 * {0,2,...} return the next OID.
816 * {0,3} return the OID of the name in "new"
817 * {0,4,...} return the kind & format info for the "..." OID.
818 * {0,5,...} return the description the "..." OID.
819 */
820
821 #ifdef SYSCTL_DEBUG
822 static void
823 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i)
824 {
825 int k;
826 struct sysctl_oid *oidp;
827
828 SYSCTL_ASSERT_LOCKED();
829 SLIST_FOREACH(oidp, l, oid_link) {
830
831 for (k=0; k<i; k++)
832 printf(" ");
833
834 printf("%d %s ", oidp->oid_number, oidp->oid_name);
835
836 printf("%c%c",
837 oidp->oid_kind & CTLFLAG_RD ? 'R':' ',
838 oidp->oid_kind & CTLFLAG_WR ? 'W':' ');
839
840 if (oidp->oid_handler)
841 printf(" *Handler");
842
843 switch (oidp->oid_kind & CTLTYPE) {
844 case CTLTYPE_NODE:
845 printf(" Node\n");
846 if (!oidp->oid_handler) {
847 sysctl_sysctl_debug_dump_node(
848 SYSCTL_CHILDREN(oidp), i + 2);
849 }
850 break;
851 case CTLTYPE_INT: printf(" Int\n"); break;
852 case CTLTYPE_UINT: printf(" u_int\n"); break;
853 case CTLTYPE_LONG: printf(" Long\n"); break;
854 case CTLTYPE_ULONG: printf(" u_long\n"); break;
855 case CTLTYPE_STRING: printf(" String\n"); break;
856 case CTLTYPE_S8: printf(" int8_t\n"); break;
857 case CTLTYPE_S16: printf(" int16_t\n"); break;
858 case CTLTYPE_S32: printf(" int32_t\n"); break;
859 case CTLTYPE_S64: printf(" int64_t\n"); break;
860 case CTLTYPE_U8: printf(" uint8_t\n"); break;
861 case CTLTYPE_U16: printf(" uint16_t\n"); break;
862 case CTLTYPE_U32: printf(" uint32_t\n"); break;
863 case CTLTYPE_U64: printf(" uint64_t\n"); break;
864 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break;
865 default: printf("\n");
866 }
867
868 }
869 }
870
871 static int
872 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS)
873 {
874 struct rm_priotracker tracker;
875 int error;
876
877 error = priv_check(req->td, PRIV_SYSCTL_DEBUG);
878 if (error)
879 return (error);
880 SYSCTL_RLOCK(&tracker);
881 sysctl_sysctl_debug_dump_node(&sysctl__children, 0);
882 SYSCTL_RUNLOCK(&tracker);
883 return (ENOENT);
884 }
885
886 SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD|CTLFLAG_MPSAFE,
887 0, 0, sysctl_sysctl_debug, "-", "");
888 #endif
889
890 static int
891 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS)
892 {
893 int *name = (int *) arg1;
894 u_int namelen = arg2;
895 int error = 0;
896 struct sysctl_oid *oid;
897 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2;
898 struct rm_priotracker tracker;
899 char buf[10];
900
901 SYSCTL_RLOCK(&tracker);
902 while (namelen) {
903 if (!lsp) {
904 snprintf(buf,sizeof(buf),"%d",*name);
905 if (req->oldidx)
906 error = SYSCTL_OUT(req, ".", 1);
907 if (!error)
908 error = SYSCTL_OUT(req, buf, strlen(buf));
909 if (error)
910 goto out;
911 namelen--;
912 name++;
913 continue;
914 }
915 lsp2 = NULL;
916 SLIST_FOREACH(oid, lsp, oid_link) {
917 if (oid->oid_number != *name)
918 continue;
919
920 if (req->oldidx)
921 error = SYSCTL_OUT(req, ".", 1);
922 if (!error)
923 error = SYSCTL_OUT(req, oid->oid_name,
924 strlen(oid->oid_name));
925 if (error)
926 goto out;
927
928 namelen--;
929 name++;
930
931 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE)
932 break;
933
934 if (oid->oid_handler)
935 break;
936
937 lsp2 = SYSCTL_CHILDREN(oid);
938 break;
939 }
940 lsp = lsp2;
941 }
942 error = SYSCTL_OUT(req, "", 1);
943 out:
944 SYSCTL_RUNLOCK(&tracker);
945 return (error);
946 }
947
948 /*
949 * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in
950 * capability mode.
951 */
952 static SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD,
953 sysctl_sysctl_name, "");
954
955 static int
956 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen,
957 int *next, int *len, int level, struct sysctl_oid **oidpp)
958 {
959 struct sysctl_oid *oidp;
960
961 SYSCTL_ASSERT_LOCKED();
962 *len = level;
963 SLIST_FOREACH(oidp, lsp, oid_link) {
964 *next = oidp->oid_number;
965 *oidpp = oidp;
966
967 if (oidp->oid_kind & CTLFLAG_SKIP)
968 continue;
969
970 if (!namelen) {
971 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
972 return (0);
973 if (oidp->oid_handler)
974 /* We really should call the handler here...*/
975 return (0);
976 lsp = SYSCTL_CHILDREN(oidp);
977 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1,
978 len, level+1, oidpp))
979 return (0);
980 goto emptynode;
981 }
982
983 if (oidp->oid_number < *name)
984 continue;
985
986 if (oidp->oid_number > *name) {
987 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
988 return (0);
989 if (oidp->oid_handler)
990 return (0);
991 lsp = SYSCTL_CHILDREN(oidp);
992 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1,
993 next+1, len, level+1, oidpp))
994 return (0);
995 goto next;
996 }
997 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
998 continue;
999
1000 if (oidp->oid_handler)
1001 continue;
1002
1003 lsp = SYSCTL_CHILDREN(oidp);
1004 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1,
1005 len, level+1, oidpp))
1006 return (0);
1007 next:
1008 namelen = 1;
1009 emptynode:
1010 *len = level;
1011 }
1012 return (1);
1013 }
1014
1015 static int
1016 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS)
1017 {
1018 int *name = (int *) arg1;
1019 u_int namelen = arg2;
1020 int i, j, error;
1021 struct sysctl_oid *oid;
1022 struct sysctl_oid_list *lsp = &sysctl__children;
1023 struct rm_priotracker tracker;
1024 int newoid[CTL_MAXNAME];
1025
1026 SYSCTL_RLOCK(&tracker);
1027 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid);
1028 SYSCTL_RUNLOCK(&tracker);
1029 if (i)
1030 return (ENOENT);
1031 error = SYSCTL_OUT(req, newoid, j * sizeof (int));
1032 return (error);
1033 }
1034
1035 /*
1036 * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in
1037 * capability mode.
1038 */
1039 static SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD,
1040 sysctl_sysctl_next, "");
1041
1042 static int
1043 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp)
1044 {
1045 struct sysctl_oid *oidp;
1046 struct sysctl_oid_list *lsp = &sysctl__children;
1047 char *p;
1048
1049 SYSCTL_ASSERT_LOCKED();
1050
1051 for (*len = 0; *len < CTL_MAXNAME;) {
1052 p = strsep(&name, ".");
1053
1054 oidp = SLIST_FIRST(lsp);
1055 for (;; oidp = SLIST_NEXT(oidp, oid_link)) {
1056 if (oidp == NULL)
1057 return (ENOENT);
1058 if (strcmp(p, oidp->oid_name) == 0)
1059 break;
1060 }
1061 *oid++ = oidp->oid_number;
1062 (*len)++;
1063
1064 if (name == NULL || *name == '\0') {
1065 if (oidpp)
1066 *oidpp = oidp;
1067 return (0);
1068 }
1069
1070 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
1071 break;
1072
1073 if (oidp->oid_handler)
1074 break;
1075
1076 lsp = SYSCTL_CHILDREN(oidp);
1077 }
1078 return (ENOENT);
1079 }
1080
1081 static int
1082 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS)
1083 {
1084 char *p;
1085 int error, oid[CTL_MAXNAME], len = 0;
1086 struct sysctl_oid *op = NULL;
1087 struct rm_priotracker tracker;
1088
1089 if (!req->newlen)
1090 return (ENOENT);
1091 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */
1092 return (ENAMETOOLONG);
1093
1094 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK);
1095
1096 error = SYSCTL_IN(req, p, req->newlen);
1097 if (error) {
1098 free(p, M_SYSCTL);
1099 return (error);
1100 }
1101
1102 p [req->newlen] = '\0';
1103
1104 SYSCTL_RLOCK(&tracker);
1105 error = name2oid(p, oid, &len, &op);
1106 SYSCTL_RUNLOCK(&tracker);
1107
1108 free(p, M_SYSCTL);
1109
1110 if (error)
1111 return (error);
1112
1113 error = SYSCTL_OUT(req, oid, len * sizeof *oid);
1114 return (error);
1115 }
1116
1117 /*
1118 * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in
1119 * capability mode.
1120 */
1121 SYSCTL_PROC(_sysctl, 3, name2oid,
1122 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_ANYBODY | CTLFLAG_MPSAFE
1123 | CTLFLAG_CAPRW, 0, 0, sysctl_sysctl_name2oid, "I", "");
1124
1125 static int
1126 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS)
1127 {
1128 struct sysctl_oid *oid;
1129 struct rm_priotracker tracker;
1130 int error;
1131
1132 SYSCTL_RLOCK(&tracker);
1133 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
1134 if (error)
1135 goto out;
1136
1137 if (oid->oid_fmt == NULL) {
1138 error = ENOENT;
1139 goto out;
1140 }
1141 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind));
1142 if (error)
1143 goto out;
1144 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1);
1145 out:
1146 SYSCTL_RUNLOCK(&tracker);
1147 return (error);
1148 }
1149
1150
1151 static SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLFLAG_CAPRD,
1152 sysctl_sysctl_oidfmt, "");
1153
1154 static int
1155 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS)
1156 {
1157 struct sysctl_oid *oid;
1158 struct rm_priotracker tracker;
1159 int error;
1160
1161 SYSCTL_RLOCK(&tracker);
1162 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
1163 if (error)
1164 goto out;
1165
1166 if (oid->oid_descr == NULL) {
1167 error = ENOENT;
1168 goto out;
1169 }
1170 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1);
1171 out:
1172 SYSCTL_RUNLOCK(&tracker);
1173 return (error);
1174 }
1175
1176 static SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLFLAG_CAPRD,
1177 sysctl_sysctl_oiddescr, "");
1178
1179 /*
1180 * Default "handler" functions.
1181 */
1182
1183 /*
1184 * Handle a bool.
1185 * Two cases:
1186 * a variable: point arg1 at it.
1187 * a constant: pass it in arg2.
1188 */
1189
1190 int
1191 sysctl_handle_bool(SYSCTL_HANDLER_ARGS)
1192 {
1193 uint8_t temp;
1194 int error;
1195
1196 /*
1197 * Attempt to get a coherent snapshot by making a copy of the data.
1198 */
1199 if (arg1)
1200 temp = *(bool *)arg1 ? 1 : 0;
1201 else
1202 temp = arg2 ? 1 : 0;
1203
1204 error = SYSCTL_OUT(req, &temp, sizeof(temp));
1205 if (error || !req->newptr)
1206 return (error);
1207
1208 if (!arg1)
1209 error = EPERM;
1210 else {
1211 error = SYSCTL_IN(req, &temp, sizeof(temp));
1212 if (!error)
1213 *(bool *)arg1 = temp ? 1 : 0;
1214 }
1215 return (error);
1216 }
1217
1218 /*
1219 * Handle an int8_t, signed or unsigned.
1220 * Two cases:
1221 * a variable: point arg1 at it.
1222 * a constant: pass it in arg2.
1223 */
1224
1225 int
1226 sysctl_handle_8(SYSCTL_HANDLER_ARGS)
1227 {
1228 int8_t tmpout;
1229 int error = 0;
1230
1231 /*
1232 * Attempt to get a coherent snapshot by making a copy of the data.
1233 */
1234 if (arg1)
1235 tmpout = *(int8_t *)arg1;
1236 else
1237 tmpout = arg2;
1238 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout));
1239
1240 if (error || !req->newptr)
1241 return (error);
1242
1243 if (!arg1)
1244 error = EPERM;
1245 else
1246 error = SYSCTL_IN(req, arg1, sizeof(tmpout));
1247 return (error);
1248 }
1249
1250 /*
1251 * Handle an int16_t, signed or unsigned.
1252 * Two cases:
1253 * a variable: point arg1 at it.
1254 * a constant: pass it in arg2.
1255 */
1256
1257 int
1258 sysctl_handle_16(SYSCTL_HANDLER_ARGS)
1259 {
1260 int16_t tmpout;
1261 int error = 0;
1262
1263 /*
1264 * Attempt to get a coherent snapshot by making a copy of the data.
1265 */
1266 if (arg1)
1267 tmpout = *(int16_t *)arg1;
1268 else
1269 tmpout = arg2;
1270 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout));
1271
1272 if (error || !req->newptr)
1273 return (error);
1274
1275 if (!arg1)
1276 error = EPERM;
1277 else
1278 error = SYSCTL_IN(req, arg1, sizeof(tmpout));
1279 return (error);
1280 }
1281
1282 /*
1283 * Handle an int32_t, signed or unsigned.
1284 * Two cases:
1285 * a variable: point arg1 at it.
1286 * a constant: pass it in arg2.
1287 */
1288
1289 int
1290 sysctl_handle_32(SYSCTL_HANDLER_ARGS)
1291 {
1292 int32_t tmpout;
1293 int error = 0;
1294
1295 /*
1296 * Attempt to get a coherent snapshot by making a copy of the data.
1297 */
1298 if (arg1)
1299 tmpout = *(int32_t *)arg1;
1300 else
1301 tmpout = arg2;
1302 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout));
1303
1304 if (error || !req->newptr)
1305 return (error);
1306
1307 if (!arg1)
1308 error = EPERM;
1309 else
1310 error = SYSCTL_IN(req, arg1, sizeof(tmpout));
1311 return (error);
1312 }
1313
1314 /*
1315 * Handle an int, signed or unsigned.
1316 * Two cases:
1317 * a variable: point arg1 at it.
1318 * a constant: pass it in arg2.
1319 */
1320
1321 int
1322 sysctl_handle_int(SYSCTL_HANDLER_ARGS)
1323 {
1324 int tmpout, error = 0;
1325
1326 /*
1327 * Attempt to get a coherent snapshot by making a copy of the data.
1328 */
1329 if (arg1)
1330 tmpout = *(int *)arg1;
1331 else
1332 tmpout = arg2;
1333 error = SYSCTL_OUT(req, &tmpout, sizeof(int));
1334
1335 if (error || !req->newptr)
1336 return (error);
1337
1338 if (!arg1)
1339 error = EPERM;
1340 else
1341 error = SYSCTL_IN(req, arg1, sizeof(int));
1342 return (error);
1343 }
1344
1345 /*
1346 * Based on on sysctl_handle_int() convert milliseconds into ticks.
1347 * Note: this is used by TCP.
1348 */
1349
1350 int
1351 sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS)
1352 {
1353 int error, s, tt;
1354
1355 tt = *(int *)arg1;
1356 s = (int)((int64_t)tt * 1000 / hz);
1357
1358 error = sysctl_handle_int(oidp, &s, 0, req);
1359 if (error || !req->newptr)
1360 return (error);
1361
1362 tt = (int)((int64_t)s * hz / 1000);
1363 if (tt < 1)
1364 return (EINVAL);
1365
1366 *(int *)arg1 = tt;
1367 return (0);
1368 }
1369
1370
1371 /*
1372 * Handle a long, signed or unsigned.
1373 * Two cases:
1374 * a variable: point arg1 at it.
1375 * a constant: pass it in arg2.
1376 */
1377
1378 int
1379 sysctl_handle_long(SYSCTL_HANDLER_ARGS)
1380 {
1381 int error = 0;
1382 long tmplong;
1383 #ifdef SCTL_MASK32
1384 int tmpint;
1385 #endif
1386
1387 /*
1388 * Attempt to get a coherent snapshot by making a copy of the data.
1389 */
1390 if (arg1)
1391 tmplong = *(long *)arg1;
1392 else
1393 tmplong = arg2;
1394 #ifdef SCTL_MASK32
1395 if (req->flags & SCTL_MASK32) {
1396 tmpint = tmplong;
1397 error = SYSCTL_OUT(req, &tmpint, sizeof(int));
1398 } else
1399 #endif
1400 error = SYSCTL_OUT(req, &tmplong, sizeof(long));
1401
1402 if (error || !req->newptr)
1403 return (error);
1404
1405 if (!arg1)
1406 error = EPERM;
1407 #ifdef SCTL_MASK32
1408 else if (req->flags & SCTL_MASK32) {
1409 error = SYSCTL_IN(req, &tmpint, sizeof(int));
1410 *(long *)arg1 = (long)tmpint;
1411 }
1412 #endif
1413 else
1414 error = SYSCTL_IN(req, arg1, sizeof(long));
1415 return (error);
1416 }
1417
1418 /*
1419 * Handle a 64 bit int, signed or unsigned.
1420 * Two cases:
1421 * a variable: point arg1 at it.
1422 * a constant: pass it in arg2.
1423 */
1424 int
1425 sysctl_handle_64(SYSCTL_HANDLER_ARGS)
1426 {
1427 int error = 0;
1428 uint64_t tmpout;
1429
1430 /*
1431 * Attempt to get a coherent snapshot by making a copy of the data.
1432 */
1433 if (arg1)
1434 tmpout = *(uint64_t *)arg1;
1435 else
1436 tmpout = arg2;
1437 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t));
1438
1439 if (error || !req->newptr)
1440 return (error);
1441
1442 if (!arg1)
1443 error = EPERM;
1444 else
1445 error = SYSCTL_IN(req, arg1, sizeof(uint64_t));
1446 return (error);
1447 }
1448
1449 /*
1450 * Handle our generic '\0' terminated 'C' string.
1451 * Two cases:
1452 * a variable string: point arg1 at it, arg2 is max length.
1453 * a constant string: point arg1 at it, arg2 is zero.
1454 */
1455
1456 int
1457 sysctl_handle_string(SYSCTL_HANDLER_ARGS)
1458 {
1459 size_t outlen;
1460 int error = 0, ro_string = 0;
1461
1462 /*
1463 * A zero-length buffer indicates a fixed size read-only
1464 * string:
1465 */
1466 if (arg2 == 0) {
1467 arg2 = strlen((char *)arg1) + 1;
1468 ro_string = 1;
1469 }
1470
1471 if (req->oldptr != NULL) {
1472 char *tmparg;
1473
1474 if (ro_string) {
1475 tmparg = arg1;
1476 } else {
1477 /* try to make a coherent snapshot of the string */
1478 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK);
1479 memcpy(tmparg, arg1, arg2);
1480 }
1481
1482 outlen = strnlen(tmparg, arg2 - 1) + 1;
1483 error = SYSCTL_OUT(req, tmparg, outlen);
1484
1485 if (!ro_string)
1486 free(tmparg, M_SYSCTLTMP);
1487 } else {
1488 outlen = strnlen((char *)arg1, arg2 - 1) + 1;
1489 error = SYSCTL_OUT(req, NULL, outlen);
1490 }
1491 if (error || !req->newptr)
1492 return (error);
1493
1494 if ((req->newlen - req->newidx) >= arg2) {
1495 error = EINVAL;
1496 } else {
1497 arg2 = (req->newlen - req->newidx);
1498 error = SYSCTL_IN(req, arg1, arg2);
1499 ((char *)arg1)[arg2] = '\0';
1500 }
1501 return (error);
1502 }
1503
1504 /*
1505 * Handle any kind of opaque data.
1506 * arg1 points to it, arg2 is the size.
1507 */
1508
1509 int
1510 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS)
1511 {
1512 int error, tries;
1513 u_int generation;
1514 struct sysctl_req req2;
1515
1516 /*
1517 * Attempt to get a coherent snapshot, by using the thread
1518 * pre-emption counter updated from within mi_switch() to
1519 * determine if we were pre-empted during a bcopy() or
1520 * copyout(). Make 3 attempts at doing this before giving up.
1521 * If we encounter an error, stop immediately.
1522 */
1523 tries = 0;
1524 req2 = *req;
1525 retry:
1526 generation = curthread->td_generation;
1527 error = SYSCTL_OUT(req, arg1, arg2);
1528 if (error)
1529 return (error);
1530 tries++;
1531 if (generation != curthread->td_generation && tries < 3) {
1532 *req = req2;
1533 goto retry;
1534 }
1535
1536 error = SYSCTL_IN(req, arg1, arg2);
1537
1538 return (error);
1539 }
1540
1541 /*
1542 * Transfer functions to/from kernel space.
1543 * XXX: rather untested at this point
1544 */
1545 static int
1546 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l)
1547 {
1548 size_t i = 0;
1549
1550 if (req->oldptr) {
1551 i = l;
1552 if (req->oldlen <= req->oldidx)
1553 i = 0;
1554 else
1555 if (i > req->oldlen - req->oldidx)
1556 i = req->oldlen - req->oldidx;
1557 if (i > 0)
1558 bcopy(p, (char *)req->oldptr + req->oldidx, i);
1559 }
1560 req->oldidx += l;
1561 if (req->oldptr && i != l)
1562 return (ENOMEM);
1563 return (0);
1564 }
1565
1566 static int
1567 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l)
1568 {
1569 if (!req->newptr)
1570 return (0);
1571 if (req->newlen - req->newidx < l)
1572 return (EINVAL);
1573 bcopy((char *)req->newptr + req->newidx, p, l);
1574 req->newidx += l;
1575 return (0);
1576 }
1577
1578 int
1579 kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old,
1580 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags)
1581 {
1582 int error = 0;
1583 struct sysctl_req req;
1584
1585 bzero(&req, sizeof req);
1586
1587 req.td = td;
1588 req.flags = flags;
1589
1590 if (oldlenp) {
1591 req.oldlen = *oldlenp;
1592 }
1593 req.validlen = req.oldlen;
1594
1595 if (old) {
1596 req.oldptr= old;
1597 }
1598
1599 if (new != NULL) {
1600 req.newlen = newlen;
1601 req.newptr = new;
1602 }
1603
1604 req.oldfunc = sysctl_old_kernel;
1605 req.newfunc = sysctl_new_kernel;
1606 req.lock = REQ_UNWIRED;
1607
1608 error = sysctl_root(0, name, namelen, &req);
1609
1610 if (req.lock == REQ_WIRED && req.validlen > 0)
1611 vsunlock(req.oldptr, req.validlen);
1612
1613 if (error && error != ENOMEM)
1614 return (error);
1615
1616 if (retval) {
1617 if (req.oldptr && req.oldidx > req.validlen)
1618 *retval = req.validlen;
1619 else
1620 *retval = req.oldidx;
1621 }
1622 return (error);
1623 }
1624
1625 int
1626 kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp,
1627 void *new, size_t newlen, size_t *retval, int flags)
1628 {
1629 int oid[CTL_MAXNAME];
1630 size_t oidlen, plen;
1631 int error;
1632
1633 oid[0] = 0; /* sysctl internal magic */
1634 oid[1] = 3; /* name2oid */
1635 oidlen = sizeof(oid);
1636
1637 error = kernel_sysctl(td, oid, 2, oid, &oidlen,
1638 (void *)name, strlen(name), &plen, flags);
1639 if (error)
1640 return (error);
1641
1642 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp,
1643 new, newlen, retval, flags);
1644 return (error);
1645 }
1646
1647 /*
1648 * Transfer function to/from user space.
1649 */
1650 static int
1651 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l)
1652 {
1653 size_t i, len, origidx;
1654 int error;
1655
1656 origidx = req->oldidx;
1657 req->oldidx += l;
1658 if (req->oldptr == NULL)
1659 return (0);
1660 /*
1661 * If we have not wired the user supplied buffer and we are currently
1662 * holding locks, drop a witness warning, as it's possible that
1663 * write operations to the user page can sleep.
1664 */
1665 if (req->lock != REQ_WIRED)
1666 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
1667 "sysctl_old_user()");
1668 i = l;
1669 len = req->validlen;
1670 if (len <= origidx)
1671 i = 0;
1672 else {
1673 if (i > len - origidx)
1674 i = len - origidx;
1675 if (req->lock == REQ_WIRED) {
1676 error = copyout_nofault(p, (char *)req->oldptr +
1677 origidx, i);
1678 } else
1679 error = copyout(p, (char *)req->oldptr + origidx, i);
1680 if (error != 0)
1681 return (error);
1682 }
1683 if (i < l)
1684 return (ENOMEM);
1685 return (0);
1686 }
1687
1688 static int
1689 sysctl_new_user(struct sysctl_req *req, void *p, size_t l)
1690 {
1691 int error;
1692
1693 if (!req->newptr)
1694 return (0);
1695 if (req->newlen - req->newidx < l)
1696 return (EINVAL);
1697 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
1698 "sysctl_new_user()");
1699 error = copyin((char *)req->newptr + req->newidx, p, l);
1700 req->newidx += l;
1701 return (error);
1702 }
1703
1704 /*
1705 * Wire the user space destination buffer. If set to a value greater than
1706 * zero, the len parameter limits the maximum amount of wired memory.
1707 */
1708 int
1709 sysctl_wire_old_buffer(struct sysctl_req *req, size_t len)
1710 {
1711 int ret;
1712 size_t wiredlen;
1713
1714 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen;
1715 ret = 0;
1716 if (req->lock != REQ_WIRED && req->oldptr &&
1717 req->oldfunc == sysctl_old_user) {
1718 if (wiredlen != 0) {
1719 ret = vslock(req->oldptr, wiredlen);
1720 if (ret != 0) {
1721 if (ret != ENOMEM)
1722 return (ret);
1723 wiredlen = 0;
1724 }
1725 }
1726 req->lock = REQ_WIRED;
1727 req->validlen = wiredlen;
1728 }
1729 return (0);
1730 }
1731
1732 int
1733 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid,
1734 int *nindx, struct sysctl_req *req)
1735 {
1736 struct sysctl_oid_list *lsp;
1737 struct sysctl_oid *oid;
1738 int indx;
1739
1740 SYSCTL_ASSERT_LOCKED();
1741 lsp = &sysctl__children;
1742 indx = 0;
1743 while (indx < CTL_MAXNAME) {
1744 SLIST_FOREACH(oid, lsp, oid_link) {
1745 if (oid->oid_number == name[indx])
1746 break;
1747 }
1748 if (oid == NULL)
1749 return (ENOENT);
1750
1751 indx++;
1752 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
1753 if (oid->oid_handler != NULL || indx == namelen) {
1754 *noid = oid;
1755 if (nindx != NULL)
1756 *nindx = indx;
1757 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0,
1758 ("%s found DYING node %p", __func__, oid));
1759 return (0);
1760 }
1761 lsp = SYSCTL_CHILDREN(oid);
1762 } else if (indx == namelen) {
1763 *noid = oid;
1764 if (nindx != NULL)
1765 *nindx = indx;
1766 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0,
1767 ("%s found DYING node %p", __func__, oid));
1768 return (0);
1769 } else {
1770 return (ENOTDIR);
1771 }
1772 }
1773 return (ENOENT);
1774 }
1775
1776 /*
1777 * Traverse our tree, and find the right node, execute whatever it points
1778 * to, and return the resulting error code.
1779 */
1780
1781 static int
1782 sysctl_root(SYSCTL_HANDLER_ARGS)
1783 {
1784 struct sysctl_oid *oid;
1785 struct rm_priotracker tracker;
1786 int error, indx, lvl;
1787
1788 SYSCTL_RLOCK(&tracker);
1789
1790 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req);
1791 if (error)
1792 goto out;
1793
1794 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
1795 /*
1796 * You can't call a sysctl when it's a node, but has
1797 * no handler. Inform the user that it's a node.
1798 * The indx may or may not be the same as namelen.
1799 */
1800 if (oid->oid_handler == NULL) {
1801 error = EISDIR;
1802 goto out;
1803 }
1804 }
1805
1806 /* Is this sysctl writable? */
1807 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) {
1808 error = EPERM;
1809 goto out;
1810 }
1811
1812 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL"));
1813
1814 #ifdef CAPABILITY_MODE
1815 /*
1816 * If the process is in capability mode, then don't permit reading or
1817 * writing unless specifically granted for the node.
1818 */
1819 if (IN_CAPABILITY_MODE(req->td)) {
1820 if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) ||
1821 (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) {
1822 error = EPERM;
1823 goto out;
1824 }
1825 }
1826 #endif
1827
1828 /* Is this sysctl sensitive to securelevels? */
1829 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) {
1830 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE;
1831 error = securelevel_gt(req->td->td_ucred, lvl);
1832 if (error)
1833 goto out;
1834 }
1835
1836 /* Is this sysctl writable by only privileged users? */
1837 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) {
1838 int priv;
1839
1840 if (oid->oid_kind & CTLFLAG_PRISON)
1841 priv = PRIV_SYSCTL_WRITEJAIL;
1842 #ifdef VIMAGE
1843 else if ((oid->oid_kind & CTLFLAG_VNET) &&
1844 prison_owns_vnet(req->td->td_ucred))
1845 priv = PRIV_SYSCTL_WRITEJAIL;
1846 #endif
1847 else
1848 priv = PRIV_SYSCTL_WRITE;
1849 error = priv_check(req->td, priv);
1850 if (error)
1851 goto out;
1852 }
1853
1854 if (!oid->oid_handler) {
1855 error = EINVAL;
1856 goto out;
1857 }
1858
1859 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
1860 arg1 = (int *)arg1 + indx;
1861 arg2 -= indx;
1862 } else {
1863 arg1 = oid->oid_arg1;
1864 arg2 = oid->oid_arg2;
1865 }
1866 #ifdef MAC
1867 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2,
1868 req);
1869 if (error != 0)
1870 goto out;
1871 #endif
1872 #ifdef VIMAGE
1873 if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL)
1874 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1);
1875 #endif
1876 error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker);
1877
1878 out:
1879 SYSCTL_RUNLOCK(&tracker);
1880 return (error);
1881 }
1882
1883 #ifndef _SYS_SYSPROTO_H_
1884 struct sysctl_args {
1885 int *name;
1886 u_int namelen;
1887 void *old;
1888 size_t *oldlenp;
1889 void *new;
1890 size_t newlen;
1891 };
1892 #endif
1893 int
1894 sys___sysctl(struct thread *td, struct sysctl_args *uap)
1895 {
1896 int error, i, name[CTL_MAXNAME];
1897 size_t j;
1898
1899 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2)
1900 return (EINVAL);
1901
1902 error = copyin(uap->name, &name, uap->namelen * sizeof(int));
1903 if (error)
1904 return (error);
1905
1906 error = userland_sysctl(td, name, uap->namelen,
1907 uap->old, uap->oldlenp, 0,
1908 uap->new, uap->newlen, &j, 0);
1909 if (error && error != ENOMEM)
1910 return (error);
1911 if (uap->oldlenp) {
1912 i = copyout(&j, uap->oldlenp, sizeof(j));
1913 if (i)
1914 return (i);
1915 }
1916 return (error);
1917 }
1918
1919 /*
1920 * This is used from various compatibility syscalls too. That's why name
1921 * must be in kernel space.
1922 */
1923 int
1924 userland_sysctl(struct thread *td, int *name, u_int namelen, void *old,
1925 size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval,
1926 int flags)
1927 {
1928 int error = 0, memlocked;
1929 struct sysctl_req req;
1930
1931 bzero(&req, sizeof req);
1932
1933 req.td = td;
1934 req.flags = flags;
1935
1936 if (oldlenp) {
1937 if (inkernel) {
1938 req.oldlen = *oldlenp;
1939 } else {
1940 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp));
1941 if (error)
1942 return (error);
1943 }
1944 }
1945 req.validlen = req.oldlen;
1946
1947 if (old) {
1948 if (!useracc(old, req.oldlen, VM_PROT_WRITE))
1949 return (EFAULT);
1950 req.oldptr= old;
1951 }
1952
1953 if (new != NULL) {
1954 if (!useracc(new, newlen, VM_PROT_READ))
1955 return (EFAULT);
1956 req.newlen = newlen;
1957 req.newptr = new;
1958 }
1959
1960 req.oldfunc = sysctl_old_user;
1961 req.newfunc = sysctl_new_user;
1962 req.lock = REQ_UNWIRED;
1963
1964 #ifdef KTRACE
1965 if (KTRPOINT(curthread, KTR_SYSCTL))
1966 ktrsysctl(name, namelen);
1967 #endif
1968
1969 if (req.oldptr && req.oldlen > PAGE_SIZE) {
1970 memlocked = 1;
1971 sx_xlock(&sysctlmemlock);
1972 } else
1973 memlocked = 0;
1974 CURVNET_SET(TD_TO_VNET(td));
1975
1976 for (;;) {
1977 req.oldidx = 0;
1978 req.newidx = 0;
1979 error = sysctl_root(0, name, namelen, &req);
1980 if (error != EAGAIN)
1981 break;
1982 kern_yield(PRI_USER);
1983 }
1984
1985 CURVNET_RESTORE();
1986
1987 if (req.lock == REQ_WIRED && req.validlen > 0)
1988 vsunlock(req.oldptr, req.validlen);
1989 if (memlocked)
1990 sx_xunlock(&sysctlmemlock);
1991
1992 if (error && error != ENOMEM)
1993 return (error);
1994
1995 if (retval) {
1996 if (req.oldptr && req.oldidx > req.validlen)
1997 *retval = req.validlen;
1998 else
1999 *retval = req.oldidx;
2000 }
2001 return (error);
2002 }
2003
2004 /*
2005 * Drain into a sysctl struct. The user buffer should be wired if a page
2006 * fault would cause issue.
2007 */
2008 static int
2009 sbuf_sysctl_drain(void *arg, const char *data, int len)
2010 {
2011 struct sysctl_req *req = arg;
2012 int error;
2013
2014 error = SYSCTL_OUT(req, data, len);
2015 KASSERT(error >= 0, ("Got unexpected negative value %d", error));
2016 return (error == 0 ? len : -error);
2017 }
2018
2019 struct sbuf *
2020 sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length,
2021 struct sysctl_req *req)
2022 {
2023
2024 /* Supply a default buffer size if none given. */
2025 if (buf == NULL && length == 0)
2026 length = 64;
2027 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL);
2028 sbuf_set_drain(s, sbuf_sysctl_drain, req);
2029 return (s);
2030 }
Cache object: c7b2be6c6a02ec95cd1c2519cab0824d
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