1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Mike Karels at Berkeley Software Design, Inc.
9 *
10 * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD
11 * project, to make these variables more userfriendly.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94
38 */
39
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42
43 #include "opt_capsicum.h"
44 #include "opt_ddb.h"
45 #include "opt_ktrace.h"
46 #include "opt_sysctl.h"
47
48 #include <sys/param.h>
49 #include <sys/fail.h>
50 #include <sys/systm.h>
51 #include <sys/capsicum.h>
52 #include <sys/kernel.h>
53 #include <sys/limits.h>
54 #include <sys/sysctl.h>
55 #include <sys/malloc.h>
56 #include <sys/priv.h>
57 #include <sys/proc.h>
58 #include <sys/jail.h>
59 #include <sys/kdb.h>
60 #include <sys/lock.h>
61 #include <sys/mutex.h>
62 #include <sys/rmlock.h>
63 #include <sys/sbuf.h>
64 #include <sys/sx.h>
65 #include <sys/sysproto.h>
66 #include <sys/uio.h>
67 #ifdef KTRACE
68 #include <sys/ktrace.h>
69 #endif
70
71 #ifdef DDB
72 #include <ddb/ddb.h>
73 #include <ddb/db_lex.h>
74 #endif
75
76 #include <net/vnet.h>
77
78 #include <security/mac/mac_framework.h>
79
80 #include <vm/vm.h>
81 #include <vm/vm_extern.h>
82
83 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic");
84 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids");
85 static MALLOC_DEFINE(M_SYSCTLTMP, "sysctltmp", "sysctl temp output buffer");
86
87 RB_GENERATE(sysctl_oid_list, sysctl_oid, oid_link, cmp_sysctl_oid);
88
89 /*
90 * The sysctllock protects the MIB tree. It also protects sysctl
91 * contexts used with dynamic sysctls. The sysctl_register_oid() and
92 * sysctl_unregister_oid() routines require the sysctllock to already
93 * be held, so the sysctl_wlock() and sysctl_wunlock() routines are
94 * provided for the few places in the kernel which need to use that
95 * API rather than using the dynamic API. Use of the dynamic API is
96 * strongly encouraged for most code.
97 *
98 * The sysctlmemlock is used to limit the amount of user memory wired for
99 * sysctl requests. This is implemented by serializing any userland
100 * sysctl requests larger than a single page via an exclusive lock.
101 *
102 * The sysctlstringlock is used to protect concurrent access to writable
103 * string nodes in sysctl_handle_string().
104 */
105 static struct rmlock sysctllock;
106 static struct sx __exclusive_cache_line sysctlmemlock;
107 static struct sx sysctlstringlock;
108
109 #define SYSCTL_WLOCK() rm_wlock(&sysctllock)
110 #define SYSCTL_WUNLOCK() rm_wunlock(&sysctllock)
111 #define SYSCTL_RLOCK(tracker) rm_rlock(&sysctllock, (tracker))
112 #define SYSCTL_RUNLOCK(tracker) rm_runlock(&sysctllock, (tracker))
113 #define SYSCTL_WLOCKED() rm_wowned(&sysctllock)
114 #define SYSCTL_ASSERT_LOCKED() rm_assert(&sysctllock, RA_LOCKED)
115 #define SYSCTL_ASSERT_WLOCKED() rm_assert(&sysctllock, RA_WLOCKED)
116 #define SYSCTL_ASSERT_RLOCKED() rm_assert(&sysctllock, RA_RLOCKED)
117 #define SYSCTL_INIT() rm_init_flags(&sysctllock, "sysctl lock", \
118 RM_SLEEPABLE)
119 #define SYSCTL_SLEEP(ch, wmesg, timo) \
120 rm_sleep(ch, &sysctllock, 0, wmesg, timo)
121
122 static int sysctl_root(SYSCTL_HANDLER_ARGS);
123
124 /* Root list */
125 struct sysctl_oid_list sysctl__children = RB_INITIALIZER(&sysctl__children);
126
127 static char* sysctl_escape_name(const char*);
128 static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del,
129 int recurse);
130 static int sysctl_old_kernel(struct sysctl_req *, const void *, size_t);
131 static int sysctl_new_kernel(struct sysctl_req *, void *, size_t);
132
133 static struct sysctl_oid *
134 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list)
135 {
136 struct sysctl_oid *oidp;
137
138 SYSCTL_ASSERT_LOCKED();
139 SYSCTL_FOREACH(oidp, list) {
140 if (strcmp(oidp->oid_name, name) == 0) {
141 return (oidp);
142 }
143 }
144 return (NULL);
145 }
146
147 /*
148 * Initialization of the MIB tree.
149 *
150 * Order by number in each list.
151 */
152 void
153 sysctl_wlock(void)
154 {
155
156 SYSCTL_WLOCK();
157 }
158
159 void
160 sysctl_wunlock(void)
161 {
162
163 SYSCTL_WUNLOCK();
164 }
165
166 static int
167 sysctl_root_handler_locked(struct sysctl_oid *oid, void *arg1, intmax_t arg2,
168 struct sysctl_req *req, struct rm_priotracker *tracker)
169 {
170 int error;
171
172 if (oid->oid_kind & CTLFLAG_DYN)
173 atomic_add_int(&oid->oid_running, 1);
174
175 if (tracker != NULL)
176 SYSCTL_RUNLOCK(tracker);
177 else
178 SYSCTL_WUNLOCK();
179
180 /*
181 * Treat set CTLFLAG_NEEDGIANT and unset CTLFLAG_MPSAFE flags the same,
182 * untill we're ready to remove all traces of Giant from sysctl(9).
183 */
184 if ((oid->oid_kind & CTLFLAG_NEEDGIANT) ||
185 (!(oid->oid_kind & CTLFLAG_MPSAFE)))
186 mtx_lock(&Giant);
187 error = oid->oid_handler(oid, arg1, arg2, req);
188 if ((oid->oid_kind & CTLFLAG_NEEDGIANT) ||
189 (!(oid->oid_kind & CTLFLAG_MPSAFE)))
190 mtx_unlock(&Giant);
191
192 KFAIL_POINT_ERROR(_debug_fail_point, sysctl_running, error);
193
194 if (tracker != NULL)
195 SYSCTL_RLOCK(tracker);
196 else
197 SYSCTL_WLOCK();
198
199 if (oid->oid_kind & CTLFLAG_DYN) {
200 if (atomic_fetchadd_int(&oid->oid_running, -1) == 1 &&
201 (oid->oid_kind & CTLFLAG_DYING) != 0)
202 wakeup(&oid->oid_running);
203 }
204
205 return (error);
206 }
207
208 static void
209 sysctl_load_tunable_by_oid_locked(struct sysctl_oid *oidp)
210 {
211 struct sysctl_req req;
212 struct sysctl_oid *curr;
213 char *penv = NULL;
214 char path[96];
215 ssize_t rem = sizeof(path);
216 ssize_t len;
217 uint8_t data[512] __aligned(sizeof(uint64_t));
218 int size;
219 int error;
220
221 path[--rem] = 0;
222
223 for (curr = oidp; curr != NULL; curr = SYSCTL_PARENT(curr)) {
224 len = strlen(curr->oid_name);
225 rem -= len;
226 if (curr != oidp)
227 rem -= 1;
228 if (rem < 0) {
229 printf("OID path exceeds %d bytes\n", (int)sizeof(path));
230 return;
231 }
232 memcpy(path + rem, curr->oid_name, len);
233 if (curr != oidp)
234 path[rem + len] = '.';
235 }
236
237 memset(&req, 0, sizeof(req));
238
239 req.td = curthread;
240 req.oldfunc = sysctl_old_kernel;
241 req.newfunc = sysctl_new_kernel;
242 req.lock = REQ_UNWIRED;
243
244 switch (oidp->oid_kind & CTLTYPE) {
245 case CTLTYPE_INT:
246 if (getenv_array(path + rem, data, sizeof(data), &size,
247 sizeof(int), GETENV_SIGNED) == 0)
248 return;
249 req.newlen = size;
250 req.newptr = data;
251 break;
252 case CTLTYPE_UINT:
253 if (getenv_array(path + rem, data, sizeof(data), &size,
254 sizeof(int), GETENV_UNSIGNED) == 0)
255 return;
256 req.newlen = size;
257 req.newptr = data;
258 break;
259 case CTLTYPE_LONG:
260 if (getenv_array(path + rem, data, sizeof(data), &size,
261 sizeof(long), GETENV_SIGNED) == 0)
262 return;
263 req.newlen = size;
264 req.newptr = data;
265 break;
266 case CTLTYPE_ULONG:
267 if (getenv_array(path + rem, data, sizeof(data), &size,
268 sizeof(long), GETENV_UNSIGNED) == 0)
269 return;
270 req.newlen = size;
271 req.newptr = data;
272 break;
273 case CTLTYPE_S8:
274 if (getenv_array(path + rem, data, sizeof(data), &size,
275 sizeof(int8_t), GETENV_SIGNED) == 0)
276 return;
277 req.newlen = size;
278 req.newptr = data;
279 break;
280 case CTLTYPE_S16:
281 if (getenv_array(path + rem, data, sizeof(data), &size,
282 sizeof(int16_t), GETENV_SIGNED) == 0)
283 return;
284 req.newlen = size;
285 req.newptr = data;
286 break;
287 case CTLTYPE_S32:
288 if (getenv_array(path + rem, data, sizeof(data), &size,
289 sizeof(int32_t), GETENV_SIGNED) == 0)
290 return;
291 req.newlen = size;
292 req.newptr = data;
293 break;
294 case CTLTYPE_S64:
295 if (getenv_array(path + rem, data, sizeof(data), &size,
296 sizeof(int64_t), GETENV_SIGNED) == 0)
297 return;
298 req.newlen = size;
299 req.newptr = data;
300 break;
301 case CTLTYPE_U8:
302 if (getenv_array(path + rem, data, sizeof(data), &size,
303 sizeof(uint8_t), GETENV_UNSIGNED) == 0)
304 return;
305 req.newlen = size;
306 req.newptr = data;
307 break;
308 case CTLTYPE_U16:
309 if (getenv_array(path + rem, data, sizeof(data), &size,
310 sizeof(uint16_t), GETENV_UNSIGNED) == 0)
311 return;
312 req.newlen = size;
313 req.newptr = data;
314 break;
315 case CTLTYPE_U32:
316 if (getenv_array(path + rem, data, sizeof(data), &size,
317 sizeof(uint32_t), GETENV_UNSIGNED) == 0)
318 return;
319 req.newlen = size;
320 req.newptr = data;
321 break;
322 case CTLTYPE_U64:
323 if (getenv_array(path + rem, data, sizeof(data), &size,
324 sizeof(uint64_t), GETENV_UNSIGNED) == 0)
325 return;
326 req.newlen = size;
327 req.newptr = data;
328 break;
329 case CTLTYPE_STRING:
330 penv = kern_getenv(path + rem);
331 if (penv == NULL)
332 return;
333 req.newlen = strlen(penv);
334 req.newptr = penv;
335 break;
336 default:
337 return;
338 }
339 error = sysctl_root_handler_locked(oidp, oidp->oid_arg1,
340 oidp->oid_arg2, &req, NULL);
341 if (error != 0)
342 printf("Setting sysctl %s failed: %d\n", path + rem, error);
343 if (penv != NULL)
344 freeenv(penv);
345 }
346
347 /*
348 * Locate the path to a given oid. Returns the length of the resulting path,
349 * or -1 if the oid was not found. nodes must have room for CTL_MAXNAME
350 * elements.
351 */
352 static int
353 sysctl_search_oid(struct sysctl_oid **nodes, struct sysctl_oid *needle)
354 {
355 int indx;
356
357 SYSCTL_ASSERT_LOCKED();
358 indx = 0;
359 /*
360 * Do a depth-first search of the oid tree, looking for 'needle'. Start
361 * with the first child of the root.
362 */
363 nodes[indx] = RB_MIN(sysctl_oid_list, &sysctl__children);
364 for (;;) {
365 if (nodes[indx] == needle)
366 return (indx + 1);
367
368 if (nodes[indx] == NULL) {
369 /* Node has no more siblings, so back up to parent. */
370 if (indx-- == 0) {
371 /* Retreat to root, so give up. */
372 break;
373 }
374 } else if ((nodes[indx]->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
375 /* Node has children. */
376 if (++indx == CTL_MAXNAME) {
377 /* Max search depth reached, so give up. */
378 break;
379 }
380 /* Start with the first child. */
381 nodes[indx] = RB_MIN(sysctl_oid_list,
382 &nodes[indx - 1]->oid_children);
383 continue;
384 }
385 /* Consider next sibling. */
386 nodes[indx] = RB_NEXT(sysctl_oid_list, NULL, nodes[indx]);
387 }
388 return (-1);
389 }
390
391 static void
392 sysctl_warn_reuse(const char *func, struct sysctl_oid *leaf)
393 {
394 struct sysctl_oid *nodes[CTL_MAXNAME];
395 char buf[128];
396 struct sbuf sb;
397 int rc, i;
398
399 (void)sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN | SBUF_INCLUDENUL);
400 sbuf_set_drain(&sb, sbuf_printf_drain, NULL);
401
402 sbuf_printf(&sb, "%s: can't re-use a leaf (", __func__);
403
404 rc = sysctl_search_oid(nodes, leaf);
405 if (rc > 0) {
406 for (i = 0; i < rc; i++)
407 sbuf_printf(&sb, "%s%.*s", nodes[i]->oid_name,
408 i != (rc - 1), ".");
409 } else {
410 sbuf_printf(&sb, "%s", leaf->oid_name);
411 }
412 sbuf_printf(&sb, ")!\n");
413
414 (void)sbuf_finish(&sb);
415 }
416
417 #ifdef SYSCTL_DEBUG
418 static int
419 sysctl_reuse_test(SYSCTL_HANDLER_ARGS)
420 {
421 struct rm_priotracker tracker;
422
423 SYSCTL_RLOCK(&tracker);
424 sysctl_warn_reuse(__func__, oidp);
425 SYSCTL_RUNLOCK(&tracker);
426 return (0);
427 }
428 SYSCTL_PROC(_sysctl, OID_AUTO, reuse_test,
429 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, sysctl_reuse_test, "-",
430 "");
431 #endif
432
433 void
434 sysctl_register_oid(struct sysctl_oid *oidp)
435 {
436 struct sysctl_oid_list *parent = oidp->oid_parent;
437 struct sysctl_oid *p, key;
438 int oid_number;
439 int timeout = 2;
440
441 /*
442 * First check if another oid with the same name already
443 * exists in the parent's list.
444 */
445 SYSCTL_ASSERT_WLOCKED();
446 p = sysctl_find_oidname(oidp->oid_name, parent);
447 if (p != NULL) {
448 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
449 p->oid_refcnt++;
450 return;
451 } else {
452 sysctl_warn_reuse(__func__, p);
453 return;
454 }
455 }
456 /* get current OID number */
457 oid_number = oidp->oid_number;
458
459 #if (OID_AUTO >= 0)
460 #error "OID_AUTO is expected to be a negative value"
461 #endif
462 /*
463 * Any negative OID number qualifies as OID_AUTO. Valid OID
464 * numbers should always be positive.
465 *
466 * NOTE: DO NOT change the starting value here, change it in
467 * <sys/sysctl.h>, and make sure it is at least 256 to
468 * accommodate e.g. net.inet.raw as a static sysctl node.
469 */
470 if (oid_number < 0) {
471 static int newoid;
472
473 /*
474 * By decrementing the next OID number we spend less
475 * time inserting the OIDs into a sorted list.
476 */
477 if (--newoid < CTL_AUTO_START)
478 newoid = 0x7fffffff;
479
480 oid_number = newoid;
481 }
482
483 /*
484 * Insert the OID into the parent's list sorted by OID number.
485 */
486 key.oid_number = oid_number;
487 p = RB_NFIND(sysctl_oid_list, parent, &key);
488 while (p != NULL && oid_number == p->oid_number) {
489 /* get the next valid OID number */
490 if (oid_number < CTL_AUTO_START ||
491 oid_number == 0x7fffffff) {
492 /* wraparound - restart */
493 oid_number = CTL_AUTO_START;
494 /* don't loop forever */
495 if (!timeout--)
496 panic("sysctl: Out of OID numbers\n");
497 key.oid_number = oid_number;
498 p = RB_NFIND(sysctl_oid_list, parent, &key);
499 continue;
500 }
501 p = RB_NEXT(sysctl_oid_list, NULL, p);
502 oid_number++;
503 }
504 /* check for non-auto OID number collision */
505 if (oidp->oid_number >= 0 && oidp->oid_number < CTL_AUTO_START &&
506 oid_number >= CTL_AUTO_START) {
507 printf("sysctl: OID number(%d) is already in use for '%s'\n",
508 oidp->oid_number, oidp->oid_name);
509 }
510 /* update the OID number, if any */
511 oidp->oid_number = oid_number;
512 RB_INSERT(sysctl_oid_list, parent, oidp);
513
514 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE &&
515 #ifdef VIMAGE
516 (oidp->oid_kind & CTLFLAG_VNET) == 0 &&
517 #endif
518 (oidp->oid_kind & CTLFLAG_TUN) != 0 &&
519 (oidp->oid_kind & CTLFLAG_NOFETCH) == 0) {
520 /* only fetch value once */
521 oidp->oid_kind |= CTLFLAG_NOFETCH;
522 /* try to fetch value from kernel environment */
523 sysctl_load_tunable_by_oid_locked(oidp);
524 }
525 }
526
527 void
528 sysctl_register_disabled_oid(struct sysctl_oid *oidp)
529 {
530
531 /*
532 * Mark the leaf as dormant if it's not to be immediately enabled.
533 * We do not disable nodes as they can be shared between modules
534 * and it is always safe to access a node.
535 */
536 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0,
537 ("internal flag is set in oid_kind"));
538 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
539 oidp->oid_kind |= CTLFLAG_DORMANT;
540 sysctl_register_oid(oidp);
541 }
542
543 void
544 sysctl_enable_oid(struct sysctl_oid *oidp)
545 {
546
547 SYSCTL_ASSERT_WLOCKED();
548 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
549 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0,
550 ("sysctl node is marked as dormant"));
551 return;
552 }
553 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) != 0,
554 ("enabling already enabled sysctl oid"));
555 oidp->oid_kind &= ~CTLFLAG_DORMANT;
556 }
557
558 void
559 sysctl_unregister_oid(struct sysctl_oid *oidp)
560 {
561 int error;
562
563 SYSCTL_ASSERT_WLOCKED();
564 if (oidp->oid_number == OID_AUTO) {
565 error = EINVAL;
566 } else {
567 error = ENOENT;
568 if (RB_REMOVE(sysctl_oid_list, oidp->oid_parent, oidp))
569 error = 0;
570 }
571
572 /*
573 * This can happen when a module fails to register and is
574 * being unloaded afterwards. It should not be a panic()
575 * for normal use.
576 */
577 if (error) {
578 printf("%s: failed(%d) to unregister sysctl(%s)\n",
579 __func__, error, oidp->oid_name);
580 }
581 }
582
583 /* Initialize a new context to keep track of dynamically added sysctls. */
584 int
585 sysctl_ctx_init(struct sysctl_ctx_list *c)
586 {
587
588 if (c == NULL) {
589 return (EINVAL);
590 }
591
592 /*
593 * No locking here, the caller is responsible for not adding
594 * new nodes to a context until after this function has
595 * returned.
596 */
597 TAILQ_INIT(c);
598 return (0);
599 }
600
601 /* Free the context, and destroy all dynamic oids registered in this context */
602 int
603 sysctl_ctx_free(struct sysctl_ctx_list *clist)
604 {
605 struct sysctl_ctx_entry *e, *e1;
606 int error;
607
608 error = 0;
609 /*
610 * First perform a "dry run" to check if it's ok to remove oids.
611 * XXX FIXME
612 * XXX This algorithm is a hack. But I don't know any
613 * XXX better solution for now...
614 */
615 SYSCTL_WLOCK();
616 TAILQ_FOREACH(e, clist, link) {
617 error = sysctl_remove_oid_locked(e->entry, 0, 0);
618 if (error)
619 break;
620 }
621 /*
622 * Restore deregistered entries, either from the end,
623 * or from the place where error occurred.
624 * e contains the entry that was not unregistered
625 */
626 if (error)
627 e1 = TAILQ_PREV(e, sysctl_ctx_list, link);
628 else
629 e1 = TAILQ_LAST(clist, sysctl_ctx_list);
630 while (e1 != NULL) {
631 sysctl_register_oid(e1->entry);
632 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link);
633 }
634 if (error) {
635 SYSCTL_WUNLOCK();
636 return(EBUSY);
637 }
638 /* Now really delete the entries */
639 e = TAILQ_FIRST(clist);
640 while (e != NULL) {
641 e1 = TAILQ_NEXT(e, link);
642 error = sysctl_remove_oid_locked(e->entry, 1, 0);
643 if (error)
644 panic("sysctl_remove_oid: corrupt tree, entry: %s",
645 e->entry->oid_name);
646 free(e, M_SYSCTLOID);
647 e = e1;
648 }
649 SYSCTL_WUNLOCK();
650 return (error);
651 }
652
653 /* Add an entry to the context */
654 struct sysctl_ctx_entry *
655 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
656 {
657 struct sysctl_ctx_entry *e;
658
659 SYSCTL_ASSERT_WLOCKED();
660 if (clist == NULL || oidp == NULL)
661 return(NULL);
662 e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK);
663 e->entry = oidp;
664 TAILQ_INSERT_HEAD(clist, e, link);
665 return (e);
666 }
667
668 /* Find an entry in the context */
669 struct sysctl_ctx_entry *
670 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
671 {
672 struct sysctl_ctx_entry *e;
673
674 SYSCTL_ASSERT_WLOCKED();
675 if (clist == NULL || oidp == NULL)
676 return(NULL);
677 TAILQ_FOREACH(e, clist, link) {
678 if (e->entry == oidp)
679 return(e);
680 }
681 return (e);
682 }
683
684 /*
685 * Delete an entry from the context.
686 * NOTE: this function doesn't free oidp! You have to remove it
687 * with sysctl_remove_oid().
688 */
689 int
690 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp)
691 {
692 struct sysctl_ctx_entry *e;
693
694 if (clist == NULL || oidp == NULL)
695 return (EINVAL);
696 SYSCTL_WLOCK();
697 e = sysctl_ctx_entry_find(clist, oidp);
698 if (e != NULL) {
699 TAILQ_REMOVE(clist, e, link);
700 SYSCTL_WUNLOCK();
701 free(e, M_SYSCTLOID);
702 return (0);
703 } else {
704 SYSCTL_WUNLOCK();
705 return (ENOENT);
706 }
707 }
708
709 /*
710 * Remove dynamically created sysctl trees.
711 * oidp - top of the tree to be removed
712 * del - if 0 - just deregister, otherwise free up entries as well
713 * recurse - if != 0 traverse the subtree to be deleted
714 */
715 int
716 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse)
717 {
718 int error;
719
720 SYSCTL_WLOCK();
721 error = sysctl_remove_oid_locked(oidp, del, recurse);
722 SYSCTL_WUNLOCK();
723 return (error);
724 }
725
726 int
727 sysctl_remove_name(struct sysctl_oid *parent, const char *name,
728 int del, int recurse)
729 {
730 struct sysctl_oid *p;
731 int error;
732
733 error = ENOENT;
734 SYSCTL_WLOCK();
735 p = sysctl_find_oidname(name, &parent->oid_children);
736 if (p)
737 error = sysctl_remove_oid_locked(p, del, recurse);
738 SYSCTL_WUNLOCK();
739
740 return (error);
741 }
742
743 /*
744 * Duplicate the provided string, escaping any illegal characters. The result
745 * must be freed when no longer in use.
746 *
747 * The list of illegal characters is ".".
748 */
749 static char*
750 sysctl_escape_name(const char* orig)
751 {
752 int i, s = 0, d = 0, nillegals = 0;
753 char *new;
754
755 /* First count the number of illegal characters */
756 for (i = 0; orig[i] != '\0'; i++) {
757 if (orig[i] == '.')
758 nillegals++;
759 }
760
761 /* Allocate storage for new string */
762 new = malloc(i + 2 * nillegals + 1, M_SYSCTLOID, M_WAITOK);
763
764 /* Copy the name, escaping characters as we go */
765 while (orig[s] != '\0') {
766 if (orig[s] == '.') {
767 /* %25 is the hexadecimal representation of '.' */
768 new[d++] = '%';
769 new[d++] = '2';
770 new[d++] = '5';
771 s++;
772 } else {
773 new[d++] = orig[s++];
774 }
775 }
776
777 /* Finally, nul-terminate */
778 new[d] = '\0';
779
780 return (new);
781 }
782
783 static int
784 sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse)
785 {
786 struct sysctl_oid *p, *tmp;
787 int error;
788
789 SYSCTL_ASSERT_WLOCKED();
790 if (oidp == NULL)
791 return(EINVAL);
792 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) {
793 printf("Warning: can't remove non-dynamic nodes (%s)!\n",
794 oidp->oid_name);
795 return (EINVAL);
796 }
797 /*
798 * WARNING: normal method to do this should be through
799 * sysctl_ctx_free(). Use recursing as the last resort
800 * method to purge your sysctl tree of leftovers...
801 * However, if some other code still references these nodes,
802 * it will panic.
803 */
804 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
805 if (oidp->oid_refcnt == 1) {
806 for(p = RB_MIN(sysctl_oid_list, &oidp->oid_children);
807 p != NULL; p = tmp) {
808 if (!recurse) {
809 printf("Warning: failed attempt to "
810 "remove oid %s with child %s\n",
811 oidp->oid_name, p->oid_name);
812 return (ENOTEMPTY);
813 }
814 tmp = RB_NEXT(sysctl_oid_list,
815 &oidp->oid_children, p);
816 error = sysctl_remove_oid_locked(p, del,
817 recurse);
818 if (error)
819 return (error);
820 }
821 }
822 }
823 if (oidp->oid_refcnt > 1 ) {
824 oidp->oid_refcnt--;
825 } else {
826 if (oidp->oid_refcnt == 0) {
827 printf("Warning: bad oid_refcnt=%u (%s)!\n",
828 oidp->oid_refcnt, oidp->oid_name);
829 return (EINVAL);
830 }
831 sysctl_unregister_oid(oidp);
832 if (del) {
833 /*
834 * Wait for all threads running the handler to drain.
835 * This preserves the previous behavior when the
836 * sysctl lock was held across a handler invocation,
837 * and is necessary for module unload correctness.
838 */
839 while (oidp->oid_running > 0) {
840 oidp->oid_kind |= CTLFLAG_DYING;
841 SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0);
842 }
843 if (oidp->oid_descr)
844 free(__DECONST(char *, oidp->oid_descr),
845 M_SYSCTLOID);
846 if (oidp->oid_label)
847 free(__DECONST(char *, oidp->oid_label),
848 M_SYSCTLOID);
849 free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID);
850 free(oidp, M_SYSCTLOID);
851 }
852 }
853 return (0);
854 }
855 /*
856 * Create new sysctls at run time.
857 * clist may point to a valid context initialized with sysctl_ctx_init().
858 */
859 struct sysctl_oid *
860 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent,
861 int number, const char *name, int kind, void *arg1, intmax_t arg2,
862 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr,
863 const char *label)
864 {
865 struct sysctl_oid *oidp;
866 char *escaped;
867
868 /* You have to hook up somewhere.. */
869 if (parent == NULL)
870 return(NULL);
871 escaped = sysctl_escape_name(name);
872 /* Check if the node already exists, otherwise create it */
873 SYSCTL_WLOCK();
874 oidp = sysctl_find_oidname(escaped, parent);
875 if (oidp != NULL) {
876 free(escaped, M_SYSCTLOID);
877 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
878 oidp->oid_refcnt++;
879 /* Update the context */
880 if (clist != NULL)
881 sysctl_ctx_entry_add(clist, oidp);
882 SYSCTL_WUNLOCK();
883 return (oidp);
884 } else {
885 sysctl_warn_reuse(__func__, oidp);
886 SYSCTL_WUNLOCK();
887 return (NULL);
888 }
889 }
890 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO);
891 oidp->oid_parent = parent;
892 RB_INIT(&oidp->oid_children);
893 oidp->oid_number = number;
894 oidp->oid_refcnt = 1;
895 oidp->oid_name = escaped;
896 oidp->oid_handler = handler;
897 oidp->oid_kind = CTLFLAG_DYN | kind;
898 oidp->oid_arg1 = arg1;
899 oidp->oid_arg2 = arg2;
900 oidp->oid_fmt = fmt;
901 if (descr != NULL)
902 oidp->oid_descr = strdup(descr, M_SYSCTLOID);
903 if (label != NULL)
904 oidp->oid_label = strdup(label, M_SYSCTLOID);
905 /* Update the context, if used */
906 if (clist != NULL)
907 sysctl_ctx_entry_add(clist, oidp);
908 /* Register this oid */
909 sysctl_register_oid(oidp);
910 SYSCTL_WUNLOCK();
911 return (oidp);
912 }
913
914 /*
915 * Rename an existing oid.
916 */
917 void
918 sysctl_rename_oid(struct sysctl_oid *oidp, const char *name)
919 {
920 char *newname;
921 char *oldname;
922
923 newname = strdup(name, M_SYSCTLOID);
924 SYSCTL_WLOCK();
925 oldname = __DECONST(char *, oidp->oid_name);
926 oidp->oid_name = newname;
927 SYSCTL_WUNLOCK();
928 free(oldname, M_SYSCTLOID);
929 }
930
931 /*
932 * Reparent an existing oid.
933 */
934 int
935 sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent)
936 {
937 struct sysctl_oid *oidp;
938
939 SYSCTL_WLOCK();
940 if (oid->oid_parent == parent) {
941 SYSCTL_WUNLOCK();
942 return (0);
943 }
944 oidp = sysctl_find_oidname(oid->oid_name, parent);
945 if (oidp != NULL) {
946 SYSCTL_WUNLOCK();
947 return (EEXIST);
948 }
949 sysctl_unregister_oid(oid);
950 oid->oid_parent = parent;
951 oid->oid_number = OID_AUTO;
952 sysctl_register_oid(oid);
953 SYSCTL_WUNLOCK();
954 return (0);
955 }
956
957 /*
958 * Register the kernel's oids on startup.
959 */
960 SET_DECLARE(sysctl_set, struct sysctl_oid);
961
962 static void
963 sysctl_register_all(void *arg)
964 {
965 struct sysctl_oid **oidp;
966
967 sx_init(&sysctlmemlock, "sysctl mem");
968 sx_init(&sysctlstringlock, "sysctl string handler");
969 SYSCTL_INIT();
970 SYSCTL_WLOCK();
971 SET_FOREACH(oidp, sysctl_set)
972 sysctl_register_oid(*oidp);
973 SYSCTL_WUNLOCK();
974 }
975 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, NULL);
976
977 /*
978 * "Staff-functions"
979 *
980 * These functions implement a presently undocumented interface
981 * used by the sysctl program to walk the tree, and get the type
982 * so it can print the value.
983 * This interface is under work and consideration, and should probably
984 * be killed with a big axe by the first person who can find the time.
985 * (be aware though, that the proper interface isn't as obvious as it
986 * may seem, there are various conflicting requirements.
987 *
988 * {CTL_SYSCTL, CTL_SYSCTL_DEBUG} printf the entire MIB-tree.
989 * {CTL_SYSCTL, CTL_SYSCTL_NAME, ...} return the name of the "..."
990 * OID.
991 * {CTL_SYSCTL, CTL_SYSCTL_NEXT, ...} return the next OID, honoring
992 * CTLFLAG_SKIP.
993 * {CTL_SYSCTL, CTL_SYSCTL_NAME2OID} return the OID of the name in
994 * "new"
995 * {CTL_SYSCTL, CTL_SYSCTL_OIDFMT, ...} return the kind & format info
996 * for the "..." OID.
997 * {CTL_SYSCTL, CTL_SYSCTL_OIDDESCR, ...} return the description of the
998 * "..." OID.
999 * {CTL_SYSCTL, CTL_SYSCTL_OIDLABEL, ...} return the aggregation label of
1000 * the "..." OID.
1001 * {CTL_SYSCTL, CTL_SYSCTL_NEXTNOSKIP, ...} return the next OID, ignoring
1002 * CTLFLAG_SKIP.
1003 */
1004
1005 #ifdef SYSCTL_DEBUG
1006 static void
1007 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i)
1008 {
1009 int k;
1010 struct sysctl_oid *oidp;
1011
1012 SYSCTL_ASSERT_LOCKED();
1013 SYSCTL_FOREACH(oidp, l) {
1014 for (k=0; k<i; k++)
1015 printf(" ");
1016
1017 printf("%d %s ", oidp->oid_number, oidp->oid_name);
1018
1019 printf("%c%c",
1020 oidp->oid_kind & CTLFLAG_RD ? 'R':' ',
1021 oidp->oid_kind & CTLFLAG_WR ? 'W':' ');
1022
1023 if (oidp->oid_handler)
1024 printf(" *Handler");
1025
1026 switch (oidp->oid_kind & CTLTYPE) {
1027 case CTLTYPE_NODE:
1028 printf(" Node\n");
1029 if (!oidp->oid_handler) {
1030 sysctl_sysctl_debug_dump_node(
1031 SYSCTL_CHILDREN(oidp), i + 2);
1032 }
1033 break;
1034 case CTLTYPE_INT: printf(" Int\n"); break;
1035 case CTLTYPE_UINT: printf(" u_int\n"); break;
1036 case CTLTYPE_LONG: printf(" Long\n"); break;
1037 case CTLTYPE_ULONG: printf(" u_long\n"); break;
1038 case CTLTYPE_STRING: printf(" String\n"); break;
1039 case CTLTYPE_S8: printf(" int8_t\n"); break;
1040 case CTLTYPE_S16: printf(" int16_t\n"); break;
1041 case CTLTYPE_S32: printf(" int32_t\n"); break;
1042 case CTLTYPE_S64: printf(" int64_t\n"); break;
1043 case CTLTYPE_U8: printf(" uint8_t\n"); break;
1044 case CTLTYPE_U16: printf(" uint16_t\n"); break;
1045 case CTLTYPE_U32: printf(" uint32_t\n"); break;
1046 case CTLTYPE_U64: printf(" uint64_t\n"); break;
1047 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break;
1048 default: printf("\n");
1049 }
1050 }
1051 }
1052
1053 static int
1054 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS)
1055 {
1056 struct rm_priotracker tracker;
1057 int error;
1058
1059 error = priv_check(req->td, PRIV_SYSCTL_DEBUG);
1060 if (error)
1061 return (error);
1062 SYSCTL_RLOCK(&tracker);
1063 sysctl_sysctl_debug_dump_node(&sysctl__children, 0);
1064 SYSCTL_RUNLOCK(&tracker);
1065 return (ENOENT);
1066 }
1067
1068 SYSCTL_PROC(_sysctl, CTL_SYSCTL_DEBUG, debug, CTLTYPE_STRING | CTLFLAG_RD |
1069 CTLFLAG_MPSAFE, 0, 0, sysctl_sysctl_debug, "-", "");
1070 #endif
1071
1072 static int
1073 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS)
1074 {
1075 int *name = (int *) arg1;
1076 u_int namelen = arg2;
1077 int error;
1078 struct sysctl_oid *oid, key;
1079 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2;
1080 struct rm_priotracker tracker;
1081 char buf[10];
1082
1083 error = sysctl_wire_old_buffer(req, 0);
1084 if (error)
1085 return (error);
1086
1087 SYSCTL_RLOCK(&tracker);
1088 while (namelen) {
1089 if (!lsp) {
1090 snprintf(buf,sizeof(buf),"%d",*name);
1091 if (req->oldidx)
1092 error = SYSCTL_OUT(req, ".", 1);
1093 if (!error)
1094 error = SYSCTL_OUT(req, buf, strlen(buf));
1095 if (error)
1096 goto out;
1097 namelen--;
1098 name++;
1099 continue;
1100 }
1101 lsp2 = NULL;
1102 key.oid_number = *name;
1103 oid = RB_FIND(sysctl_oid_list, lsp, &key);
1104 if (oid) {
1105 if (req->oldidx)
1106 error = SYSCTL_OUT(req, ".", 1);
1107 if (!error)
1108 error = SYSCTL_OUT(req, oid->oid_name,
1109 strlen(oid->oid_name));
1110 if (error)
1111 goto out;
1112
1113 namelen--;
1114 name++;
1115
1116 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE &&
1117 !oid->oid_handler)
1118 lsp2 = SYSCTL_CHILDREN(oid);
1119 }
1120 lsp = lsp2;
1121 }
1122 error = SYSCTL_OUT(req, "", 1);
1123 out:
1124 SYSCTL_RUNLOCK(&tracker);
1125 return (error);
1126 }
1127
1128 /*
1129 * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in
1130 * capability mode.
1131 */
1132 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NAME, name, CTLFLAG_RD |
1133 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_name, "");
1134
1135 enum sysctl_iter_action {
1136 ITER_SIBLINGS, /* Not matched, continue iterating siblings */
1137 ITER_CHILDREN, /* Node has children we need to iterate over them */
1138 ITER_FOUND, /* Matching node was found */
1139 };
1140
1141 /*
1142 * Tries to find the next node for @name and @namelen.
1143 *
1144 * Returns next action to take.
1145 */
1146 static enum sysctl_iter_action
1147 sysctl_sysctl_next_node(struct sysctl_oid *oidp, int *name, unsigned int namelen,
1148 bool honor_skip)
1149 {
1150
1151 if ((oidp->oid_kind & CTLFLAG_DORMANT) != 0)
1152 return (ITER_SIBLINGS);
1153
1154 if (honor_skip && (oidp->oid_kind & CTLFLAG_SKIP) != 0)
1155 return (ITER_SIBLINGS);
1156
1157 if (namelen == 0) {
1158 /*
1159 * We have reached a node with a full name match and are
1160 * looking for the next oid in its children.
1161 *
1162 * For CTL_SYSCTL_NEXTNOSKIP we are done.
1163 *
1164 * For CTL_SYSCTL_NEXT we skip CTLTYPE_NODE (unless it
1165 * has a handler) and move on to the children.
1166 */
1167 if (!honor_skip)
1168 return (ITER_FOUND);
1169 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
1170 return (ITER_FOUND);
1171 /* If node does not have an iterator, treat it as leaf */
1172 if (oidp->oid_handler)
1173 return (ITER_FOUND);
1174
1175 /* Report oid as a node to iterate */
1176 return (ITER_CHILDREN);
1177 }
1178
1179 /*
1180 * No match yet. Continue seeking the given name.
1181 *
1182 * We are iterating in order by oid_number, so skip oids lower
1183 * than the one we are looking for.
1184 *
1185 * When the current oid_number is higher than the one we seek,
1186 * that means we have reached the next oid in the sequence and
1187 * should return it.
1188 *
1189 * If the oid_number matches the name at this level then we
1190 * have to find a node to continue searching at the next level.
1191 */
1192 if (oidp->oid_number < *name)
1193 return (ITER_SIBLINGS);
1194 if (oidp->oid_number > *name) {
1195 /*
1196 * We have reached the next oid.
1197 *
1198 * For CTL_SYSCTL_NEXTNOSKIP we are done.
1199 *
1200 * For CTL_SYSCTL_NEXT we skip CTLTYPE_NODE (unless it
1201 * has a handler) and move on to the children.
1202 */
1203 if (!honor_skip)
1204 return (ITER_FOUND);
1205 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
1206 return (ITER_FOUND);
1207 /* If node does not have an iterator, treat it as leaf */
1208 if (oidp->oid_handler)
1209 return (ITER_FOUND);
1210 return (ITER_CHILDREN);
1211 }
1212
1213 /* match at a current level */
1214 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
1215 return (ITER_SIBLINGS);
1216 if (oidp->oid_handler)
1217 return (ITER_SIBLINGS);
1218
1219 return (ITER_CHILDREN);
1220 }
1221
1222 /*
1223 * Recursively walk the sysctl subtree at lsp until we find the given name.
1224 * Returns true and fills in next oid data in @next and @len if oid is found.
1225 */
1226 static bool
1227 sysctl_sysctl_next_action(struct sysctl_oid_list *lsp, int *name, u_int namelen,
1228 int *next, int *len, int level, bool honor_skip)
1229 {
1230 struct sysctl_oid_list *next_lsp;
1231 struct sysctl_oid *oidp = NULL, key;
1232 bool success = false;
1233 enum sysctl_iter_action action;
1234
1235 SYSCTL_ASSERT_LOCKED();
1236 /*
1237 * Start the search at the requested oid. But if not found, then scan
1238 * through all children.
1239 */
1240 if (namelen > 0) {
1241 key.oid_number = *name;
1242 oidp = RB_FIND(sysctl_oid_list, lsp, &key);
1243 }
1244 if (!oidp)
1245 oidp = RB_MIN(sysctl_oid_list, lsp);
1246 for(; oidp != NULL; oidp = RB_NEXT(sysctl_oid_list, lsp, oidp)) {
1247 action = sysctl_sysctl_next_node(oidp, name, namelen,
1248 honor_skip);
1249 if (action == ITER_SIBLINGS)
1250 continue;
1251 if (action == ITER_FOUND) {
1252 success = true;
1253 break;
1254 }
1255 KASSERT((action== ITER_CHILDREN), ("ret(%d)!=ITER_CHILDREN", action));
1256
1257 next_lsp = SYSCTL_CHILDREN(oidp);
1258 if (namelen == 0) {
1259 success = sysctl_sysctl_next_action(next_lsp, NULL, 0,
1260 next + 1, len, level + 1, honor_skip);
1261 } else {
1262 success = sysctl_sysctl_next_action(next_lsp, name + 1,
1263 namelen - 1, next + 1, len, level + 1, honor_skip);
1264 if (!success) {
1265
1266 /*
1267 * We maintain the invariant that current node oid
1268 * is >= the oid provided in @name.
1269 * As there are no usable children at this node,
1270 * current node oid is strictly > than the requested
1271 * oid.
1272 * Hence, reduce namelen to 0 to allow for picking first
1273 * nodes/leafs in the next node in list.
1274 */
1275 namelen = 0;
1276 }
1277 }
1278 if (success)
1279 break;
1280 }
1281
1282 if (success) {
1283 *next = oidp->oid_number;
1284 if (level > *len)
1285 *len = level;
1286 }
1287
1288 return (success);
1289 }
1290
1291 static int
1292 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS)
1293 {
1294 int *name = (int *) arg1;
1295 u_int namelen = arg2;
1296 int len, error;
1297 bool success;
1298 struct sysctl_oid_list *lsp = &sysctl__children;
1299 struct rm_priotracker tracker;
1300 int next[CTL_MAXNAME];
1301
1302 len = 0;
1303 SYSCTL_RLOCK(&tracker);
1304 success = sysctl_sysctl_next_action(lsp, name, namelen, next, &len, 1,
1305 oidp->oid_number == CTL_SYSCTL_NEXT);
1306 SYSCTL_RUNLOCK(&tracker);
1307 if (!success)
1308 return (ENOENT);
1309 error = SYSCTL_OUT(req, next, len * sizeof (int));
1310 return (error);
1311 }
1312
1313 /*
1314 * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in
1315 * capability mode.
1316 */
1317 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXT, next, CTLFLAG_RD |
1318 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, "");
1319
1320 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXTNOSKIP, nextnoskip, CTLFLAG_RD |
1321 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, "");
1322
1323 static int
1324 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp)
1325 {
1326 struct sysctl_oid *oidp;
1327 struct sysctl_oid_list *lsp = &sysctl__children;
1328
1329 SYSCTL_ASSERT_LOCKED();
1330
1331 for (*len = 0; *len < CTL_MAXNAME;) {
1332 oidp = sysctl_find_oidname(strsep(&name, "."), lsp);
1333 if (oidp == NULL)
1334 return (ENOENT);
1335 *oid++ = oidp->oid_number;
1336 (*len)++;
1337
1338 if (name == NULL || *name == '\0') {
1339 if (oidpp)
1340 *oidpp = oidp;
1341 return (0);
1342 }
1343
1344 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE)
1345 break;
1346
1347 if (oidp->oid_handler)
1348 break;
1349
1350 lsp = SYSCTL_CHILDREN(oidp);
1351 }
1352 return (ENOENT);
1353 }
1354
1355 static int
1356 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS)
1357 {
1358 char *p;
1359 int error, oid[CTL_MAXNAME], len = 0;
1360 struct sysctl_oid *op = NULL;
1361 struct rm_priotracker tracker;
1362 char buf[32];
1363
1364 if (!req->newlen)
1365 return (ENOENT);
1366 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */
1367 return (ENAMETOOLONG);
1368
1369 p = buf;
1370 if (req->newlen >= sizeof(buf))
1371 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK);
1372
1373 error = SYSCTL_IN(req, p, req->newlen);
1374 if (error) {
1375 if (p != buf)
1376 free(p, M_SYSCTL);
1377 return (error);
1378 }
1379
1380 p [req->newlen] = '\0';
1381
1382 SYSCTL_RLOCK(&tracker);
1383 error = name2oid(p, oid, &len, &op);
1384 SYSCTL_RUNLOCK(&tracker);
1385
1386 if (p != buf)
1387 free(p, M_SYSCTL);
1388
1389 if (error)
1390 return (error);
1391
1392 error = SYSCTL_OUT(req, oid, len * sizeof *oid);
1393 return (error);
1394 }
1395
1396 /*
1397 * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in
1398 * capability mode.
1399 */
1400 SYSCTL_PROC(_sysctl, CTL_SYSCTL_NAME2OID, name2oid, CTLTYPE_INT | CTLFLAG_RW |
1401 CTLFLAG_ANYBODY | CTLFLAG_MPSAFE | CTLFLAG_CAPRW, 0, 0,
1402 sysctl_sysctl_name2oid, "I", "");
1403
1404 static int
1405 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS)
1406 {
1407 struct sysctl_oid *oid;
1408 struct rm_priotracker tracker;
1409 int error;
1410
1411 error = sysctl_wire_old_buffer(req, 0);
1412 if (error)
1413 return (error);
1414
1415 SYSCTL_RLOCK(&tracker);
1416 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
1417 if (error)
1418 goto out;
1419
1420 if (oid->oid_fmt == NULL) {
1421 error = ENOENT;
1422 goto out;
1423 }
1424 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind));
1425 if (error)
1426 goto out;
1427 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1);
1428 out:
1429 SYSCTL_RUNLOCK(&tracker);
1430 return (error);
1431 }
1432
1433 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDFMT, oidfmt, CTLFLAG_RD |
1434 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidfmt, "");
1435
1436 static int
1437 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS)
1438 {
1439 struct sysctl_oid *oid;
1440 struct rm_priotracker tracker;
1441 int error;
1442
1443 error = sysctl_wire_old_buffer(req, 0);
1444 if (error)
1445 return (error);
1446
1447 SYSCTL_RLOCK(&tracker);
1448 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
1449 if (error)
1450 goto out;
1451
1452 if (oid->oid_descr == NULL) {
1453 error = ENOENT;
1454 goto out;
1455 }
1456 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1);
1457 out:
1458 SYSCTL_RUNLOCK(&tracker);
1459 return (error);
1460 }
1461
1462 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDDESCR, oiddescr, CTLFLAG_RD |
1463 CTLFLAG_MPSAFE|CTLFLAG_CAPRD, sysctl_sysctl_oiddescr, "");
1464
1465 static int
1466 sysctl_sysctl_oidlabel(SYSCTL_HANDLER_ARGS)
1467 {
1468 struct sysctl_oid *oid;
1469 struct rm_priotracker tracker;
1470 int error;
1471
1472 error = sysctl_wire_old_buffer(req, 0);
1473 if (error)
1474 return (error);
1475
1476 SYSCTL_RLOCK(&tracker);
1477 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req);
1478 if (error)
1479 goto out;
1480
1481 if (oid->oid_label == NULL) {
1482 error = ENOENT;
1483 goto out;
1484 }
1485 error = SYSCTL_OUT(req, oid->oid_label, strlen(oid->oid_label) + 1);
1486 out:
1487 SYSCTL_RUNLOCK(&tracker);
1488 return (error);
1489 }
1490
1491 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDLABEL, oidlabel, CTLFLAG_RD |
1492 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidlabel, "");
1493
1494 /*
1495 * Default "handler" functions.
1496 */
1497
1498 /*
1499 * Handle a bool.
1500 * Two cases:
1501 * a variable: point arg1 at it.
1502 * a constant: pass it in arg2.
1503 */
1504
1505 int
1506 sysctl_handle_bool(SYSCTL_HANDLER_ARGS)
1507 {
1508 uint8_t temp;
1509 int error;
1510
1511 /*
1512 * Attempt to get a coherent snapshot by making a copy of the data.
1513 */
1514 if (arg1)
1515 temp = *(bool *)arg1 ? 1 : 0;
1516 else
1517 temp = arg2 ? 1 : 0;
1518
1519 error = SYSCTL_OUT(req, &temp, sizeof(temp));
1520 if (error || !req->newptr)
1521 return (error);
1522
1523 if (!arg1)
1524 error = EPERM;
1525 else {
1526 error = SYSCTL_IN(req, &temp, sizeof(temp));
1527 if (!error)
1528 *(bool *)arg1 = temp ? 1 : 0;
1529 }
1530 return (error);
1531 }
1532
1533 /*
1534 * Handle an int8_t, signed or unsigned.
1535 * Two cases:
1536 * a variable: point arg1 at it.
1537 * a constant: pass it in arg2.
1538 */
1539
1540 int
1541 sysctl_handle_8(SYSCTL_HANDLER_ARGS)
1542 {
1543 int8_t tmpout;
1544 int error = 0;
1545
1546 /*
1547 * Attempt to get a coherent snapshot by making a copy of the data.
1548 */
1549 if (arg1)
1550 tmpout = *(int8_t *)arg1;
1551 else
1552 tmpout = arg2;
1553 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout));
1554
1555 if (error || !req->newptr)
1556 return (error);
1557
1558 if (!arg1)
1559 error = EPERM;
1560 else
1561 error = SYSCTL_IN(req, arg1, sizeof(tmpout));
1562 return (error);
1563 }
1564
1565 /*
1566 * Handle an int16_t, signed or unsigned.
1567 * Two cases:
1568 * a variable: point arg1 at it.
1569 * a constant: pass it in arg2.
1570 */
1571
1572 int
1573 sysctl_handle_16(SYSCTL_HANDLER_ARGS)
1574 {
1575 int16_t tmpout;
1576 int error = 0;
1577
1578 /*
1579 * Attempt to get a coherent snapshot by making a copy of the data.
1580 */
1581 if (arg1)
1582 tmpout = *(int16_t *)arg1;
1583 else
1584 tmpout = arg2;
1585 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout));
1586
1587 if (error || !req->newptr)
1588 return (error);
1589
1590 if (!arg1)
1591 error = EPERM;
1592 else
1593 error = SYSCTL_IN(req, arg1, sizeof(tmpout));
1594 return (error);
1595 }
1596
1597 /*
1598 * Handle an int32_t, signed or unsigned.
1599 * Two cases:
1600 * a variable: point arg1 at it.
1601 * a constant: pass it in arg2.
1602 */
1603
1604 int
1605 sysctl_handle_32(SYSCTL_HANDLER_ARGS)
1606 {
1607 int32_t tmpout;
1608 int error = 0;
1609
1610 /*
1611 * Attempt to get a coherent snapshot by making a copy of the data.
1612 */
1613 if (arg1)
1614 tmpout = *(int32_t *)arg1;
1615 else
1616 tmpout = arg2;
1617 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout));
1618
1619 if (error || !req->newptr)
1620 return (error);
1621
1622 if (!arg1)
1623 error = EPERM;
1624 else
1625 error = SYSCTL_IN(req, arg1, sizeof(tmpout));
1626 return (error);
1627 }
1628
1629 /*
1630 * Handle an int, signed or unsigned.
1631 * Two cases:
1632 * a variable: point arg1 at it.
1633 * a constant: pass it in arg2.
1634 */
1635
1636 int
1637 sysctl_handle_int(SYSCTL_HANDLER_ARGS)
1638 {
1639 int tmpout, error = 0;
1640
1641 /*
1642 * Attempt to get a coherent snapshot by making a copy of the data.
1643 */
1644 if (arg1)
1645 tmpout = *(int *)arg1;
1646 else
1647 tmpout = arg2;
1648 error = SYSCTL_OUT(req, &tmpout, sizeof(int));
1649
1650 if (error || !req->newptr)
1651 return (error);
1652
1653 if (!arg1)
1654 error = EPERM;
1655 else
1656 error = SYSCTL_IN(req, arg1, sizeof(int));
1657 return (error);
1658 }
1659
1660 /*
1661 * Based on on sysctl_handle_int() convert milliseconds into ticks.
1662 * Note: this is used by TCP.
1663 */
1664
1665 int
1666 sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS)
1667 {
1668 int error, s, tt;
1669
1670 tt = *(int *)arg1;
1671 s = (int)((int64_t)tt * 1000 / hz);
1672
1673 error = sysctl_handle_int(oidp, &s, 0, req);
1674 if (error || !req->newptr)
1675 return (error);
1676
1677 tt = (int)((int64_t)s * hz / 1000);
1678 if (tt < 1)
1679 return (EINVAL);
1680
1681 *(int *)arg1 = tt;
1682 return (0);
1683 }
1684
1685 /*
1686 * Handle a long, signed or unsigned.
1687 * Two cases:
1688 * a variable: point arg1 at it.
1689 * a constant: pass it in arg2.
1690 */
1691
1692 int
1693 sysctl_handle_long(SYSCTL_HANDLER_ARGS)
1694 {
1695 int error = 0;
1696 long tmplong;
1697 #ifdef SCTL_MASK32
1698 int tmpint;
1699 #endif
1700
1701 /*
1702 * Attempt to get a coherent snapshot by making a copy of the data.
1703 */
1704 if (arg1)
1705 tmplong = *(long *)arg1;
1706 else
1707 tmplong = arg2;
1708 #ifdef SCTL_MASK32
1709 if (req->flags & SCTL_MASK32) {
1710 tmpint = tmplong;
1711 error = SYSCTL_OUT(req, &tmpint, sizeof(int));
1712 } else
1713 #endif
1714 error = SYSCTL_OUT(req, &tmplong, sizeof(long));
1715
1716 if (error || !req->newptr)
1717 return (error);
1718
1719 if (!arg1)
1720 error = EPERM;
1721 #ifdef SCTL_MASK32
1722 else if (req->flags & SCTL_MASK32) {
1723 error = SYSCTL_IN(req, &tmpint, sizeof(int));
1724 *(long *)arg1 = (long)tmpint;
1725 }
1726 #endif
1727 else
1728 error = SYSCTL_IN(req, arg1, sizeof(long));
1729 return (error);
1730 }
1731
1732 /*
1733 * Handle a 64 bit int, signed or unsigned.
1734 * Two cases:
1735 * a variable: point arg1 at it.
1736 * a constant: pass it in arg2.
1737 */
1738 int
1739 sysctl_handle_64(SYSCTL_HANDLER_ARGS)
1740 {
1741 int error = 0;
1742 uint64_t tmpout;
1743
1744 /*
1745 * Attempt to get a coherent snapshot by making a copy of the data.
1746 */
1747 if (arg1)
1748 tmpout = *(uint64_t *)arg1;
1749 else
1750 tmpout = arg2;
1751 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t));
1752
1753 if (error || !req->newptr)
1754 return (error);
1755
1756 if (!arg1)
1757 error = EPERM;
1758 else
1759 error = SYSCTL_IN(req, arg1, sizeof(uint64_t));
1760 return (error);
1761 }
1762
1763 /*
1764 * Handle our generic '\0' terminated 'C' string.
1765 * Two cases:
1766 * a variable string: point arg1 at it, arg2 is max length.
1767 * a constant string: point arg1 at it, arg2 is zero.
1768 */
1769
1770 int
1771 sysctl_handle_string(SYSCTL_HANDLER_ARGS)
1772 {
1773 char *tmparg;
1774 size_t outlen;
1775 int error = 0, ro_string = 0;
1776
1777 /*
1778 * If the sysctl isn't writable and isn't a preallocated tunable that
1779 * can be modified by kenv(2), microoptimise and treat it as a
1780 * read-only string.
1781 * A zero-length buffer indicates a fixed size read-only
1782 * string. In ddb, don't worry about trying to make a malloced
1783 * snapshot.
1784 */
1785 if ((oidp->oid_kind & (CTLFLAG_WR | CTLFLAG_TUN)) == 0 ||
1786 arg2 == 0 || kdb_active) {
1787 arg2 = strlen((char *)arg1) + 1;
1788 ro_string = 1;
1789 }
1790
1791 if (req->oldptr != NULL) {
1792 if (ro_string) {
1793 tmparg = arg1;
1794 outlen = strlen(tmparg) + 1;
1795 } else {
1796 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK);
1797 sx_slock(&sysctlstringlock);
1798 memcpy(tmparg, arg1, arg2);
1799 sx_sunlock(&sysctlstringlock);
1800 outlen = strlen(tmparg) + 1;
1801 }
1802
1803 error = SYSCTL_OUT(req, tmparg, outlen);
1804
1805 if (!ro_string)
1806 free(tmparg, M_SYSCTLTMP);
1807 } else {
1808 if (!ro_string)
1809 sx_slock(&sysctlstringlock);
1810 outlen = strlen((char *)arg1) + 1;
1811 if (!ro_string)
1812 sx_sunlock(&sysctlstringlock);
1813 error = SYSCTL_OUT(req, NULL, outlen);
1814 }
1815 if (error || !req->newptr)
1816 return (error);
1817
1818 if (req->newlen - req->newidx >= arg2 ||
1819 req->newlen - req->newidx < 0) {
1820 error = EINVAL;
1821 } else if (req->newlen - req->newidx == 0) {
1822 sx_xlock(&sysctlstringlock);
1823 ((char *)arg1)[0] = '\0';
1824 sx_xunlock(&sysctlstringlock);
1825 } else if (req->newfunc == sysctl_new_kernel) {
1826 arg2 = req->newlen - req->newidx;
1827 sx_xlock(&sysctlstringlock);
1828 error = SYSCTL_IN(req, arg1, arg2);
1829 if (error == 0) {
1830 ((char *)arg1)[arg2] = '\0';
1831 req->newidx += arg2;
1832 }
1833 sx_xunlock(&sysctlstringlock);
1834 } else {
1835 arg2 = req->newlen - req->newidx;
1836 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK);
1837
1838 error = SYSCTL_IN(req, tmparg, arg2);
1839 if (error) {
1840 free(tmparg, M_SYSCTLTMP);
1841 return (error);
1842 }
1843
1844 sx_xlock(&sysctlstringlock);
1845 memcpy(arg1, tmparg, arg2);
1846 ((char *)arg1)[arg2] = '\0';
1847 sx_xunlock(&sysctlstringlock);
1848 free(tmparg, M_SYSCTLTMP);
1849 req->newidx += arg2;
1850 }
1851 return (error);
1852 }
1853
1854 /*
1855 * Handle any kind of opaque data.
1856 * arg1 points to it, arg2 is the size.
1857 */
1858
1859 int
1860 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS)
1861 {
1862 int error, tries;
1863 u_int generation;
1864 struct sysctl_req req2;
1865
1866 /*
1867 * Attempt to get a coherent snapshot, by using the thread
1868 * pre-emption counter updated from within mi_switch() to
1869 * determine if we were pre-empted during a bcopy() or
1870 * copyout(). Make 3 attempts at doing this before giving up.
1871 * If we encounter an error, stop immediately.
1872 */
1873 tries = 0;
1874 req2 = *req;
1875 retry:
1876 generation = curthread->td_generation;
1877 error = SYSCTL_OUT(req, arg1, arg2);
1878 if (error)
1879 return (error);
1880 tries++;
1881 if (generation != curthread->td_generation && tries < 3) {
1882 *req = req2;
1883 goto retry;
1884 }
1885
1886 error = SYSCTL_IN(req, arg1, arg2);
1887
1888 return (error);
1889 }
1890
1891 /*
1892 * Based on on sysctl_handle_64() convert microseconds to a sbintime.
1893 */
1894 int
1895 sysctl_usec_to_sbintime(SYSCTL_HANDLER_ARGS)
1896 {
1897 int error;
1898 int64_t usec;
1899
1900 usec = sbttous(*(sbintime_t *)arg1);
1901
1902 error = sysctl_handle_64(oidp, &usec, 0, req);
1903 if (error || !req->newptr)
1904 return (error);
1905
1906 *(sbintime_t *)arg1 = ustosbt(usec);
1907
1908 return (0);
1909 }
1910
1911 /*
1912 * Based on on sysctl_handle_64() convert milliseconds to a sbintime.
1913 */
1914 int
1915 sysctl_msec_to_sbintime(SYSCTL_HANDLER_ARGS)
1916 {
1917 int error;
1918 int64_t msec;
1919
1920 msec = sbttoms(*(sbintime_t *)arg1);
1921
1922 error = sysctl_handle_64(oidp, &msec, 0, req);
1923 if (error || !req->newptr)
1924 return (error);
1925
1926 *(sbintime_t *)arg1 = mstosbt(msec);
1927
1928 return (0);
1929 }
1930
1931 /*
1932 * Convert seconds to a struct timeval. Intended for use with
1933 * intervals and thus does not permit negative seconds.
1934 */
1935 int
1936 sysctl_sec_to_timeval(SYSCTL_HANDLER_ARGS)
1937 {
1938 struct timeval *tv;
1939 int error, secs;
1940
1941 tv = arg1;
1942 secs = tv->tv_sec;
1943
1944 error = sysctl_handle_int(oidp, &secs, 0, req);
1945 if (error || req->newptr == NULL)
1946 return (error);
1947
1948 if (secs < 0)
1949 return (EINVAL);
1950 tv->tv_sec = secs;
1951
1952 return (0);
1953 }
1954
1955 /*
1956 * Transfer functions to/from kernel space.
1957 * XXX: rather untested at this point
1958 */
1959 static int
1960 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l)
1961 {
1962 size_t i = 0;
1963
1964 if (req->oldptr) {
1965 i = l;
1966 if (req->oldlen <= req->oldidx)
1967 i = 0;
1968 else
1969 if (i > req->oldlen - req->oldidx)
1970 i = req->oldlen - req->oldidx;
1971 if (i > 0)
1972 bcopy(p, (char *)req->oldptr + req->oldidx, i);
1973 }
1974 req->oldidx += l;
1975 if (req->oldptr && i != l)
1976 return (ENOMEM);
1977 return (0);
1978 }
1979
1980 static int
1981 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l)
1982 {
1983 if (!req->newptr)
1984 return (0);
1985 if (req->newlen - req->newidx < l)
1986 return (EINVAL);
1987 bcopy((const char *)req->newptr + req->newidx, p, l);
1988 req->newidx += l;
1989 return (0);
1990 }
1991
1992 int
1993 kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old,
1994 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags)
1995 {
1996 int error = 0;
1997 struct sysctl_req req;
1998
1999 bzero(&req, sizeof req);
2000
2001 req.td = td;
2002 req.flags = flags;
2003
2004 if (oldlenp) {
2005 req.oldlen = *oldlenp;
2006 }
2007 req.validlen = req.oldlen;
2008
2009 if (old) {
2010 req.oldptr= old;
2011 }
2012
2013 if (new != NULL) {
2014 req.newlen = newlen;
2015 req.newptr = new;
2016 }
2017
2018 req.oldfunc = sysctl_old_kernel;
2019 req.newfunc = sysctl_new_kernel;
2020 req.lock = REQ_UNWIRED;
2021
2022 error = sysctl_root(0, name, namelen, &req);
2023
2024 if (req.lock == REQ_WIRED && req.validlen > 0)
2025 vsunlock(req.oldptr, req.validlen);
2026
2027 if (error && error != ENOMEM)
2028 return (error);
2029
2030 if (retval) {
2031 if (req.oldptr && req.oldidx > req.validlen)
2032 *retval = req.validlen;
2033 else
2034 *retval = req.oldidx;
2035 }
2036 return (error);
2037 }
2038
2039 int
2040 kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp,
2041 void *new, size_t newlen, size_t *retval, int flags)
2042 {
2043 int oid[CTL_MAXNAME];
2044 size_t oidlen, plen;
2045 int error;
2046
2047 oid[0] = CTL_SYSCTL;
2048 oid[1] = CTL_SYSCTL_NAME2OID;
2049 oidlen = sizeof(oid);
2050
2051 error = kernel_sysctl(td, oid, 2, oid, &oidlen,
2052 (void *)name, strlen(name), &plen, flags);
2053 if (error)
2054 return (error);
2055
2056 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp,
2057 new, newlen, retval, flags);
2058 return (error);
2059 }
2060
2061 /*
2062 * Transfer function to/from user space.
2063 */
2064 static int
2065 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l)
2066 {
2067 size_t i, len, origidx;
2068 int error;
2069
2070 origidx = req->oldidx;
2071 req->oldidx += l;
2072 if (req->oldptr == NULL)
2073 return (0);
2074 /*
2075 * If we have not wired the user supplied buffer and we are currently
2076 * holding locks, drop a witness warning, as it's possible that
2077 * write operations to the user page can sleep.
2078 */
2079 if (req->lock != REQ_WIRED)
2080 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2081 "sysctl_old_user()");
2082 i = l;
2083 len = req->validlen;
2084 if (len <= origidx)
2085 i = 0;
2086 else {
2087 if (i > len - origidx)
2088 i = len - origidx;
2089 if (req->lock == REQ_WIRED) {
2090 error = copyout_nofault(p, (char *)req->oldptr +
2091 origidx, i);
2092 } else
2093 error = copyout(p, (char *)req->oldptr + origidx, i);
2094 if (error != 0)
2095 return (error);
2096 }
2097 if (i < l)
2098 return (ENOMEM);
2099 return (0);
2100 }
2101
2102 static int
2103 sysctl_new_user(struct sysctl_req *req, void *p, size_t l)
2104 {
2105 int error;
2106
2107 if (!req->newptr)
2108 return (0);
2109 if (req->newlen - req->newidx < l)
2110 return (EINVAL);
2111 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,
2112 "sysctl_new_user()");
2113 error = copyin((const char *)req->newptr + req->newidx, p, l);
2114 req->newidx += l;
2115 return (error);
2116 }
2117
2118 /*
2119 * Wire the user space destination buffer. If set to a value greater than
2120 * zero, the len parameter limits the maximum amount of wired memory.
2121 */
2122 int
2123 sysctl_wire_old_buffer(struct sysctl_req *req, size_t len)
2124 {
2125 int ret;
2126 size_t wiredlen;
2127
2128 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen;
2129 ret = 0;
2130 if (req->lock != REQ_WIRED && req->oldptr &&
2131 req->oldfunc == sysctl_old_user) {
2132 if (wiredlen != 0) {
2133 ret = vslock(req->oldptr, wiredlen);
2134 if (ret != 0) {
2135 if (ret != ENOMEM)
2136 return (ret);
2137 wiredlen = 0;
2138 }
2139 }
2140 req->lock = REQ_WIRED;
2141 req->validlen = wiredlen;
2142 }
2143 return (0);
2144 }
2145
2146 int
2147 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid,
2148 int *nindx, struct sysctl_req *req)
2149 {
2150 struct sysctl_oid_list *lsp;
2151 struct sysctl_oid *oid;
2152 struct sysctl_oid key;
2153 int indx;
2154
2155 SYSCTL_ASSERT_LOCKED();
2156 lsp = &sysctl__children;
2157 indx = 0;
2158 while (indx < CTL_MAXNAME) {
2159 key.oid_number = name[indx];
2160 oid = RB_FIND(sysctl_oid_list, lsp, &key);
2161 if (oid == NULL)
2162 return (ENOENT);
2163
2164 indx++;
2165 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
2166 if (oid->oid_handler != NULL || indx == namelen) {
2167 *noid = oid;
2168 if (nindx != NULL)
2169 *nindx = indx;
2170 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0,
2171 ("%s found DYING node %p", __func__, oid));
2172 return (0);
2173 }
2174 lsp = SYSCTL_CHILDREN(oid);
2175 } else if (indx == namelen) {
2176 if ((oid->oid_kind & CTLFLAG_DORMANT) != 0)
2177 return (ENOENT);
2178 *noid = oid;
2179 if (nindx != NULL)
2180 *nindx = indx;
2181 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0,
2182 ("%s found DYING node %p", __func__, oid));
2183 return (0);
2184 } else {
2185 return (ENOTDIR);
2186 }
2187 }
2188 return (ENOENT);
2189 }
2190
2191 /*
2192 * Traverse our tree, and find the right node, execute whatever it points
2193 * to, and return the resulting error code.
2194 */
2195
2196 static int
2197 sysctl_root(SYSCTL_HANDLER_ARGS)
2198 {
2199 struct sysctl_oid *oid;
2200 struct rm_priotracker tracker;
2201 int error, indx, lvl;
2202
2203 SYSCTL_RLOCK(&tracker);
2204
2205 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req);
2206 if (error)
2207 goto out;
2208
2209 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
2210 /*
2211 * You can't call a sysctl when it's a node, but has
2212 * no handler. Inform the user that it's a node.
2213 * The indx may or may not be the same as namelen.
2214 */
2215 if (oid->oid_handler == NULL) {
2216 error = EISDIR;
2217 goto out;
2218 }
2219 }
2220
2221 /* Is this sysctl writable? */
2222 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) {
2223 error = EPERM;
2224 goto out;
2225 }
2226
2227 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL"));
2228
2229 #ifdef CAPABILITY_MODE
2230 /*
2231 * If the process is in capability mode, then don't permit reading or
2232 * writing unless specifically granted for the node.
2233 */
2234 if (IN_CAPABILITY_MODE(req->td)) {
2235 if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) ||
2236 (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) {
2237 error = EPERM;
2238 goto out;
2239 }
2240 }
2241 #endif
2242
2243 /* Is this sysctl sensitive to securelevels? */
2244 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) {
2245 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE;
2246 error = securelevel_gt(req->td->td_ucred, lvl);
2247 if (error)
2248 goto out;
2249 }
2250
2251 /* Is this sysctl writable by only privileged users? */
2252 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) {
2253 int priv;
2254
2255 if (oid->oid_kind & CTLFLAG_PRISON)
2256 priv = PRIV_SYSCTL_WRITEJAIL;
2257 #ifdef VIMAGE
2258 else if ((oid->oid_kind & CTLFLAG_VNET) &&
2259 prison_owns_vnet(req->td->td_ucred))
2260 priv = PRIV_SYSCTL_WRITEJAIL;
2261 #endif
2262 else
2263 priv = PRIV_SYSCTL_WRITE;
2264 error = priv_check(req->td, priv);
2265 if (error)
2266 goto out;
2267 }
2268
2269 if (!oid->oid_handler) {
2270 error = EINVAL;
2271 goto out;
2272 }
2273
2274 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
2275 arg1 = (int *)arg1 + indx;
2276 arg2 -= indx;
2277 } else {
2278 arg1 = oid->oid_arg1;
2279 arg2 = oid->oid_arg2;
2280 }
2281 #ifdef MAC
2282 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2,
2283 req);
2284 if (error != 0)
2285 goto out;
2286 #endif
2287 #ifdef VIMAGE
2288 if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL)
2289 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1);
2290 #endif
2291 error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker);
2292
2293 out:
2294 SYSCTL_RUNLOCK(&tracker);
2295 return (error);
2296 }
2297
2298 #ifndef _SYS_SYSPROTO_H_
2299 struct __sysctl_args {
2300 int *name;
2301 u_int namelen;
2302 void *old;
2303 size_t *oldlenp;
2304 void *new;
2305 size_t newlen;
2306 };
2307 #endif
2308 int
2309 sys___sysctl(struct thread *td, struct __sysctl_args *uap)
2310 {
2311 int error, i, name[CTL_MAXNAME];
2312 size_t j;
2313
2314 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2)
2315 return (EINVAL);
2316
2317 error = copyin(uap->name, &name, uap->namelen * sizeof(int));
2318 if (error)
2319 return (error);
2320
2321 error = userland_sysctl(td, name, uap->namelen,
2322 uap->old, uap->oldlenp, 0,
2323 uap->new, uap->newlen, &j, 0);
2324 if (error && error != ENOMEM)
2325 return (error);
2326 if (uap->oldlenp) {
2327 i = copyout(&j, uap->oldlenp, sizeof(j));
2328 if (i)
2329 return (i);
2330 }
2331 return (error);
2332 }
2333
2334 int
2335 kern___sysctlbyname(struct thread *td, const char *oname, size_t namelen,
2336 void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval,
2337 int flags, bool inkernel)
2338 {
2339 int oid[CTL_MAXNAME];
2340 char namebuf[16];
2341 char *name;
2342 size_t oidlen;
2343 int error;
2344
2345 if (namelen > MAXPATHLEN || namelen == 0)
2346 return (EINVAL);
2347 name = namebuf;
2348 if (namelen > sizeof(namebuf))
2349 name = malloc(namelen, M_SYSCTL, M_WAITOK);
2350 error = copyin(oname, name, namelen);
2351 if (error != 0)
2352 goto out;
2353
2354 oid[0] = CTL_SYSCTL;
2355 oid[1] = CTL_SYSCTL_NAME2OID;
2356 oidlen = sizeof(oid);
2357 error = kernel_sysctl(td, oid, 2, oid, &oidlen, (void *)name, namelen,
2358 retval, flags);
2359 if (error != 0)
2360 goto out;
2361 error = userland_sysctl(td, oid, *retval / sizeof(int), old, oldlenp,
2362 inkernel, new, newlen, retval, flags);
2363
2364 out:
2365 if (namelen > sizeof(namebuf))
2366 free(name, M_SYSCTL);
2367 return (error);
2368 }
2369
2370 #ifndef _SYS_SYSPROTO_H_
2371 struct __sysctlbyname_args {
2372 const char *name;
2373 size_t namelen;
2374 void *old;
2375 size_t *oldlenp;
2376 void *new;
2377 size_t newlen;
2378 };
2379 #endif
2380 int
2381 sys___sysctlbyname(struct thread *td, struct __sysctlbyname_args *uap)
2382 {
2383 size_t rv;
2384 int error;
2385
2386 error = kern___sysctlbyname(td, uap->name, uap->namelen, uap->old,
2387 uap->oldlenp, uap->new, uap->newlen, &rv, 0, 0);
2388 if (error != 0)
2389 return (error);
2390 if (uap->oldlenp != NULL)
2391 error = copyout(&rv, uap->oldlenp, sizeof(rv));
2392
2393 return (error);
2394 }
2395
2396 /*
2397 * This is used from various compatibility syscalls too. That's why name
2398 * must be in kernel space.
2399 */
2400 int
2401 userland_sysctl(struct thread *td, int *name, u_int namelen, void *old,
2402 size_t *oldlenp, int inkernel, const void *new, size_t newlen,
2403 size_t *retval, int flags)
2404 {
2405 int error = 0, memlocked;
2406 struct sysctl_req req;
2407
2408 bzero(&req, sizeof req);
2409
2410 req.td = td;
2411 req.flags = flags;
2412
2413 if (oldlenp) {
2414 if (inkernel) {
2415 req.oldlen = *oldlenp;
2416 } else {
2417 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp));
2418 if (error)
2419 return (error);
2420 }
2421 }
2422 req.validlen = req.oldlen;
2423 req.oldptr = old;
2424
2425 if (new != NULL) {
2426 req.newlen = newlen;
2427 req.newptr = new;
2428 }
2429
2430 req.oldfunc = sysctl_old_user;
2431 req.newfunc = sysctl_new_user;
2432 req.lock = REQ_UNWIRED;
2433
2434 #ifdef KTRACE
2435 if (KTRPOINT(curthread, KTR_SYSCTL))
2436 ktrsysctl(name, namelen);
2437 #endif
2438 memlocked = 0;
2439 if (req.oldptr && req.oldlen > 4 * PAGE_SIZE) {
2440 memlocked = 1;
2441 sx_xlock(&sysctlmemlock);
2442 }
2443 CURVNET_SET(TD_TO_VNET(td));
2444
2445 for (;;) {
2446 req.oldidx = 0;
2447 req.newidx = 0;
2448 error = sysctl_root(0, name, namelen, &req);
2449 if (error != EAGAIN)
2450 break;
2451 kern_yield(PRI_USER);
2452 }
2453
2454 CURVNET_RESTORE();
2455
2456 if (req.lock == REQ_WIRED && req.validlen > 0)
2457 vsunlock(req.oldptr, req.validlen);
2458 if (memlocked)
2459 sx_xunlock(&sysctlmemlock);
2460
2461 if (error && error != ENOMEM)
2462 return (error);
2463
2464 if (retval) {
2465 if (req.oldptr && req.oldidx > req.validlen)
2466 *retval = req.validlen;
2467 else
2468 *retval = req.oldidx;
2469 }
2470 return (error);
2471 }
2472
2473 /*
2474 * Drain into a sysctl struct. The user buffer should be wired if a page
2475 * fault would cause issue.
2476 */
2477 static int
2478 sbuf_sysctl_drain(void *arg, const char *data, int len)
2479 {
2480 struct sysctl_req *req = arg;
2481 int error;
2482
2483 error = SYSCTL_OUT(req, data, len);
2484 KASSERT(error >= 0, ("Got unexpected negative value %d", error));
2485 return (error == 0 ? len : -error);
2486 }
2487
2488 struct sbuf *
2489 sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length,
2490 struct sysctl_req *req)
2491 {
2492
2493 /* Supply a default buffer size if none given. */
2494 if (buf == NULL && length == 0)
2495 length = 64;
2496 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL);
2497 sbuf_set_drain(s, sbuf_sysctl_drain, req);
2498 return (s);
2499 }
2500
2501 #ifdef DDB
2502
2503 /* The current OID the debugger is working with */
2504 static struct sysctl_oid *g_ddb_oid;
2505
2506 /* The current flags specified by the user */
2507 static int g_ddb_sysctl_flags;
2508
2509 /* Check to see if the last sysctl printed */
2510 static int g_ddb_sysctl_printed;
2511
2512 static const int ctl_sign[CTLTYPE+1] = {
2513 [CTLTYPE_INT] = 1,
2514 [CTLTYPE_LONG] = 1,
2515 [CTLTYPE_S8] = 1,
2516 [CTLTYPE_S16] = 1,
2517 [CTLTYPE_S32] = 1,
2518 [CTLTYPE_S64] = 1,
2519 };
2520
2521 static const int ctl_size[CTLTYPE+1] = {
2522 [CTLTYPE_INT] = sizeof(int),
2523 [CTLTYPE_UINT] = sizeof(u_int),
2524 [CTLTYPE_LONG] = sizeof(long),
2525 [CTLTYPE_ULONG] = sizeof(u_long),
2526 [CTLTYPE_S8] = sizeof(int8_t),
2527 [CTLTYPE_S16] = sizeof(int16_t),
2528 [CTLTYPE_S32] = sizeof(int32_t),
2529 [CTLTYPE_S64] = sizeof(int64_t),
2530 [CTLTYPE_U8] = sizeof(uint8_t),
2531 [CTLTYPE_U16] = sizeof(uint16_t),
2532 [CTLTYPE_U32] = sizeof(uint32_t),
2533 [CTLTYPE_U64] = sizeof(uint64_t),
2534 };
2535
2536 #define DB_SYSCTL_NAME_ONLY 0x001 /* Compare with -N */
2537 #define DB_SYSCTL_VALUE_ONLY 0x002 /* Compare with -n */
2538 #define DB_SYSCTL_OPAQUE 0x004 /* Compare with -o */
2539 #define DB_SYSCTL_HEX 0x008 /* Compare with -x */
2540
2541 #define DB_SYSCTL_SAFE_ONLY 0x100 /* Only simple types */
2542
2543 static const char db_sysctl_modifs[] = {
2544 'N', 'n', 'o', 'x',
2545 };
2546
2547 static const int db_sysctl_modif_values[] = {
2548 DB_SYSCTL_NAME_ONLY, DB_SYSCTL_VALUE_ONLY,
2549 DB_SYSCTL_OPAQUE, DB_SYSCTL_HEX,
2550 };
2551
2552 /* Handlers considered safe to print while recursing */
2553 static int (* const db_safe_handlers[])(SYSCTL_HANDLER_ARGS) = {
2554 sysctl_handle_bool,
2555 sysctl_handle_8,
2556 sysctl_handle_16,
2557 sysctl_handle_32,
2558 sysctl_handle_64,
2559 sysctl_handle_int,
2560 sysctl_handle_long,
2561 sysctl_handle_string,
2562 sysctl_handle_opaque,
2563 };
2564
2565 /*
2566 * Use in place of sysctl_old_kernel to print sysctl values.
2567 *
2568 * Compare to the output handling in show_var from sbin/sysctl/sysctl.c
2569 */
2570 static int
2571 sysctl_old_ddb(struct sysctl_req *req, const void *ptr, size_t len)
2572 {
2573 const u_char *val, *p;
2574 const char *sep1;
2575 size_t intlen, slen;
2576 uintmax_t umv;
2577 intmax_t mv;
2578 int sign, ctltype, hexlen, xflag, error;
2579
2580 /* Suppress false-positive GCC uninitialized variable warnings */
2581 mv = 0;
2582 umv = 0;
2583
2584 slen = len;
2585 val = p = ptr;
2586
2587 if (ptr == NULL) {
2588 error = 0;
2589 goto out;
2590 }
2591
2592 /* We are going to print */
2593 g_ddb_sysctl_printed = 1;
2594
2595 xflag = g_ddb_sysctl_flags & DB_SYSCTL_HEX;
2596
2597 ctltype = (g_ddb_oid->oid_kind & CTLTYPE);
2598 sign = ctl_sign[ctltype];
2599 intlen = ctl_size[ctltype];
2600
2601 switch (ctltype) {
2602 case CTLTYPE_NODE:
2603 case CTLTYPE_STRING:
2604 db_printf("%.*s", (int) len, (const char *) p);
2605 error = 0;
2606 goto out;
2607
2608 case CTLTYPE_INT:
2609 case CTLTYPE_UINT:
2610 case CTLTYPE_LONG:
2611 case CTLTYPE_ULONG:
2612 case CTLTYPE_S8:
2613 case CTLTYPE_S16:
2614 case CTLTYPE_S32:
2615 case CTLTYPE_S64:
2616 case CTLTYPE_U8:
2617 case CTLTYPE_U16:
2618 case CTLTYPE_U32:
2619 case CTLTYPE_U64:
2620 hexlen = 2 + (intlen * CHAR_BIT + 3) / 4;
2621 sep1 = "";
2622 while (len >= intlen) {
2623 switch (ctltype) {
2624 case CTLTYPE_INT:
2625 case CTLTYPE_UINT:
2626 umv = *(const u_int *)p;
2627 mv = *(const int *)p;
2628 break;
2629 case CTLTYPE_LONG:
2630 case CTLTYPE_ULONG:
2631 umv = *(const u_long *)p;
2632 mv = *(const long *)p;
2633 break;
2634 case CTLTYPE_S8:
2635 case CTLTYPE_U8:
2636 umv = *(const uint8_t *)p;
2637 mv = *(const int8_t *)p;
2638 break;
2639 case CTLTYPE_S16:
2640 case CTLTYPE_U16:
2641 umv = *(const uint16_t *)p;
2642 mv = *(const int16_t *)p;
2643 break;
2644 case CTLTYPE_S32:
2645 case CTLTYPE_U32:
2646 umv = *(const uint32_t *)p;
2647 mv = *(const int32_t *)p;
2648 break;
2649 case CTLTYPE_S64:
2650 case CTLTYPE_U64:
2651 umv = *(const uint64_t *)p;
2652 mv = *(const int64_t *)p;
2653 break;
2654 }
2655
2656 db_printf("%s", sep1);
2657 if (xflag)
2658 db_printf("%#0*jx", hexlen, umv);
2659 else if (!sign)
2660 db_printf("%ju", umv);
2661 else if (g_ddb_oid->oid_fmt[1] == 'K') {
2662 /* Kelvins are currently unsupported. */
2663 error = EOPNOTSUPP;
2664 goto out;
2665 } else
2666 db_printf("%jd", mv);
2667
2668 sep1 = " ";
2669 len -= intlen;
2670 p += intlen;
2671 }
2672 error = 0;
2673 goto out;
2674
2675 case CTLTYPE_OPAQUE:
2676 /* TODO: Support struct functions. */
2677
2678 /* FALLTHROUGH */
2679 default:
2680 db_printf("Format:%s Length:%zu Dump:0x",
2681 g_ddb_oid->oid_fmt, len);
2682 while (len-- && (xflag || p < val + 16))
2683 db_printf("%02x", *p++);
2684 if (!xflag && len > 16)
2685 db_printf("...");
2686 error = 0;
2687 goto out;
2688 }
2689
2690 out:
2691 req->oldidx += slen;
2692 return (error);
2693 }
2694
2695 /*
2696 * Avoid setting new sysctl values from the debugger
2697 */
2698 static int
2699 sysctl_new_ddb(struct sysctl_req *req, void *p, size_t l)
2700 {
2701
2702 if (!req->newptr)
2703 return (0);
2704
2705 /* Changing sysctls from the debugger is currently unsupported */
2706 return (EPERM);
2707 }
2708
2709 /*
2710 * Run a sysctl handler with the DDB oldfunc and newfunc attached.
2711 * Instead of copying any output to a buffer we'll dump it right to
2712 * the console.
2713 */
2714 static int
2715 db_sysctl(struct sysctl_oid *oidp, int *name, u_int namelen,
2716 void *old, size_t *oldlenp, size_t *retval, int flags)
2717 {
2718 struct sysctl_req req;
2719 int error;
2720
2721 /* Setup the request */
2722 bzero(&req, sizeof req);
2723 req.td = kdb_thread;
2724 req.oldfunc = sysctl_old_ddb;
2725 req.newfunc = sysctl_new_ddb;
2726 req.lock = REQ_UNWIRED;
2727 if (oldlenp) {
2728 req.oldlen = *oldlenp;
2729 }
2730 req.validlen = req.oldlen;
2731 if (old) {
2732 req.oldptr = old;
2733 }
2734
2735 /* Setup our globals for sysctl_old_ddb */
2736 g_ddb_oid = oidp;
2737 g_ddb_sysctl_flags = flags;
2738 g_ddb_sysctl_printed = 0;
2739
2740 error = sysctl_root(0, name, namelen, &req);
2741
2742 /* Reset globals */
2743 g_ddb_oid = NULL;
2744 g_ddb_sysctl_flags = 0;
2745
2746 if (retval) {
2747 if (req.oldptr && req.oldidx > req.validlen)
2748 *retval = req.validlen;
2749 else
2750 *retval = req.oldidx;
2751 }
2752 return (error);
2753 }
2754
2755 /*
2756 * Show a sysctl's name
2757 */
2758 static void
2759 db_show_oid_name(int *oid, size_t nlen)
2760 {
2761 struct sysctl_oid *oidp;
2762 int qoid[CTL_MAXNAME + 2];
2763 int error;
2764
2765 qoid[0] = CTL_SYSCTL;
2766 qoid[1] = CTL_SYSCTL_NAME;
2767 memcpy(qoid + 2, oid, nlen * sizeof(int));
2768
2769 error = sysctl_find_oid(qoid, nlen + 2, &oidp, NULL, NULL);
2770 if (error)
2771 db_error("sysctl name oid");
2772
2773 error = db_sysctl(oidp, qoid, nlen + 2, NULL, NULL, NULL, 0);
2774 if (error)
2775 db_error("sysctl name");
2776 }
2777
2778 /*
2779 * Check to see if an OID is safe to print from ddb.
2780 */
2781 static bool
2782 db_oid_safe(const struct sysctl_oid *oidp)
2783 {
2784 for (unsigned int i = 0; i < nitems(db_safe_handlers); ++i) {
2785 if (oidp->oid_handler == db_safe_handlers[i])
2786 return (true);
2787 }
2788
2789 return (false);
2790 }
2791
2792 /*
2793 * Show a sysctl at a specific OID
2794 * Compare to the input handling in show_var from sbin/sysctl/sysctl.c
2795 */
2796 static int
2797 db_show_oid(struct sysctl_oid *oidp, int *oid, size_t nlen, int flags)
2798 {
2799 int error, xflag, oflag, Nflag, nflag;
2800 size_t len;
2801
2802 xflag = flags & DB_SYSCTL_HEX;
2803 oflag = flags & DB_SYSCTL_OPAQUE;
2804 nflag = flags & DB_SYSCTL_VALUE_ONLY;
2805 Nflag = flags & DB_SYSCTL_NAME_ONLY;
2806
2807 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_OPAQUE &&
2808 (!xflag && !oflag))
2809 return (0);
2810
2811 if (Nflag) {
2812 db_show_oid_name(oid, nlen);
2813 error = 0;
2814 goto out;
2815 }
2816
2817 if (!nflag) {
2818 db_show_oid_name(oid, nlen);
2819 db_printf(": ");
2820 }
2821
2822 if ((flags & DB_SYSCTL_SAFE_ONLY) && !db_oid_safe(oidp)) {
2823 db_printf("Skipping, unsafe to print while recursing.");
2824 error = 0;
2825 goto out;
2826 }
2827
2828 /* Try once, and ask about the size */
2829 len = 0;
2830 error = db_sysctl(oidp, oid, nlen,
2831 NULL, NULL, &len, flags);
2832 if (error)
2833 goto out;
2834
2835 if (!g_ddb_sysctl_printed)
2836 /* Lie about the size */
2837 error = db_sysctl(oidp, oid, nlen,
2838 (void *) 1, &len, NULL, flags);
2839
2840 out:
2841 db_printf("\n");
2842 return (error);
2843 }
2844
2845 /*
2846 * Show all sysctls under a specific OID
2847 * Compare to sysctl_all from sbin/sysctl/sysctl.c
2848 */
2849 static int
2850 db_show_sysctl_all(int *oid, size_t len, int flags)
2851 {
2852 struct sysctl_oid *oidp;
2853 int qoid[CTL_MAXNAME + 2], next[CTL_MAXNAME];
2854 size_t nlen;
2855
2856 qoid[0] = CTL_SYSCTL;
2857 qoid[1] = CTL_SYSCTL_NEXT;
2858 if (len) {
2859 nlen = len;
2860 memcpy(&qoid[2], oid, nlen * sizeof(int));
2861 } else {
2862 nlen = 1;
2863 qoid[2] = CTL_KERN;
2864 }
2865 for (;;) {
2866 int error;
2867 size_t nextsize = sizeof(next);
2868
2869 error = kernel_sysctl(kdb_thread, qoid, nlen + 2,
2870 next, &nextsize, NULL, 0, &nlen, 0);
2871 if (error != 0) {
2872 if (error == ENOENT)
2873 return (0);
2874 else
2875 db_error("sysctl(next)");
2876 }
2877
2878 nlen /= sizeof(int);
2879
2880 if (nlen < (unsigned int)len)
2881 return (0);
2882
2883 if (memcmp(&oid[0], &next[0], len * sizeof(int)) != 0)
2884 return (0);
2885
2886 /* Find the OID in question */
2887 error = sysctl_find_oid(next, nlen, &oidp, NULL, NULL);
2888 if (error)
2889 return (error);
2890
2891 (void)db_show_oid(oidp, next, nlen, flags | DB_SYSCTL_SAFE_ONLY);
2892
2893 if (db_pager_quit)
2894 return (0);
2895
2896 memcpy(&qoid[2 + len], &next[len], (nlen - len) * sizeof(int));
2897 }
2898 }
2899
2900 /*
2901 * Show a sysctl by its user facing string
2902 */
2903 static int
2904 db_sysctlbyname(char *name, int flags)
2905 {
2906 struct sysctl_oid *oidp;
2907 int oid[CTL_MAXNAME];
2908 int error, nlen;
2909
2910 error = name2oid(name, oid, &nlen, &oidp);
2911 if (error) {
2912 return (error);
2913 }
2914
2915 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) {
2916 db_show_sysctl_all(oid, nlen, flags);
2917 } else {
2918 error = db_show_oid(oidp, oid, nlen, flags);
2919 }
2920
2921 return (error);
2922 }
2923
2924 static void
2925 db_sysctl_cmd_usage(void)
2926 {
2927 db_printf(
2928 " sysctl [/Nnox] <sysctl> \n"
2929 " \n"
2930 " <sysctl> The name of the sysctl to show. \n"
2931 " \n"
2932 " Show a sysctl by hooking into SYSCTL_IN and SYSCTL_OUT. \n"
2933 " This will work for most sysctls, but should not be used \n"
2934 " with sysctls that are known to malloc. \n"
2935 " \n"
2936 " While recursing any \"unsafe\" sysctls will be skipped. \n"
2937 " Call sysctl directly on the sysctl to try printing the \n"
2938 " skipped sysctl. This is unsafe and may make the ddb \n"
2939 " session unusable. \n"
2940 " \n"
2941 " Arguments: \n"
2942 " /N Display only the name of the sysctl. \n"
2943 " /n Display only the value of the sysctl. \n"
2944 " /o Display opaque values. \n"
2945 " /x Display the sysctl in hex. \n"
2946 " \n"
2947 "For example: \n"
2948 "sysctl vm.v_free_min \n"
2949 "vn.v_free_min: 12669 \n"
2950 );
2951 }
2952
2953 /*
2954 * Show a specific sysctl similar to sysctl (8).
2955 */
2956 DB_COMMAND_FLAGS(sysctl, db_sysctl_cmd, CS_OWN)
2957 {
2958 char name[TOK_STRING_SIZE];
2959 int error, i, t, flags;
2960
2961 /* Parse the modifiers */
2962 t = db_read_token();
2963 if (t == tSLASH || t == tMINUS) {
2964 t = db_read_token();
2965 if (t != tIDENT) {
2966 db_printf("Bad modifier\n");
2967 error = EINVAL;
2968 goto out;
2969 }
2970 db_strcpy(modif, db_tok_string);
2971 }
2972 else {
2973 db_unread_token(t);
2974 modif[0] = '\0';
2975 }
2976
2977 flags = 0;
2978 for (i = 0; i < nitems(db_sysctl_modifs); i++) {
2979 if (strchr(modif, db_sysctl_modifs[i])) {
2980 flags |= db_sysctl_modif_values[i];
2981 }
2982 }
2983
2984 /* Parse the sysctl names */
2985 t = db_read_token();
2986 if (t != tIDENT) {
2987 db_printf("Need sysctl name\n");
2988 error = EINVAL;
2989 goto out;
2990 }
2991
2992 /* Copy the name into a temporary buffer */
2993 db_strcpy(name, db_tok_string);
2994
2995 /* Ensure there is no trailing cruft */
2996 t = db_read_token();
2997 if (t != tEOL) {
2998 db_printf("Unexpected sysctl argument\n");
2999 error = EINVAL;
3000 goto out;
3001 }
3002
3003 error = db_sysctlbyname(name, flags);
3004 if (error == ENOENT) {
3005 db_printf("unknown oid: '%s'\n", db_tok_string);
3006 goto out;
3007 } else if (error) {
3008 db_printf("%s: error: %d\n", db_tok_string, error);
3009 goto out;
3010 }
3011
3012 out:
3013 /* Ensure we eat all of our text */
3014 db_flush_lex();
3015
3016 if (error == EINVAL) {
3017 db_sysctl_cmd_usage();
3018 }
3019 }
3020
3021 #endif /* DDB */
Cache object: f4c5f331484414936819f43a6fefb339
|