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: stable/11/sys/kern/kern_sysctl.c 359652 2020-04-06 07:16:31Z 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 73static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic"); 74static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids"); 75static 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 */ 90static struct rmlock sysctllock; 91static struct sx __exclusive_cache_line 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 106static int sysctl_root(SYSCTL_HANDLER_ARGS); 107 108/* Root list */ 109struct sysctl_oid_list sysctl__children = SLIST_HEAD_INITIALIZER(&sysctl__children); 110 111static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, 112 int recurse); 113static int sysctl_old_kernel(struct sysctl_req *, const void *, size_t); 114static int sysctl_new_kernel(struct sysctl_req *, void *, size_t); 115 116static struct sysctl_oid * 117sysctl_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 */ 135void 136sysctl_wlock(void) 137{ 138 139 SYSCTL_WLOCK(); 140} 141 142void 143sysctl_wunlock(void) 144{ 145 146 SYSCTL_WUNLOCK(); 147} 148 149static int 150sysctl_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 185static void 186sysctl_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[96]; 192 ssize_t rem = sizeof(path); 193 ssize_t len; 194 uint8_t data[512] __aligned(sizeof(uint64_t)); 195 int size; 196 int error; 197 198 path[--rem] = 0; 199 200 for (curr = oidp; curr != NULL; curr = SYSCTL_PARENT(curr)) { 201 len = strlen(curr->oid_name); 202 rem -= len; 203 if (curr != oidp) 204 rem -= 1; 205 if (rem < 0) { 206 printf("OID path exceeds %d bytes\n", (int)sizeof(path)); 207 return; 208 } 209 memcpy(path + rem, curr->oid_name, len); 210 if (curr != oidp) 211 path[rem + len] = '.'; 212 } 213 214 memset(&req, 0, sizeof(req)); 215 216 req.td = curthread; 217 req.oldfunc = sysctl_old_kernel; 218 req.newfunc = sysctl_new_kernel; 219 req.lock = REQ_UNWIRED; 220 221 switch (oidp->oid_kind & CTLTYPE) { 222 case CTLTYPE_INT: 223 if (getenv_array(path + rem, data, sizeof(data), &size, 224 sizeof(int), GETENV_SIGNED) == 0) 225 return; 226 req.newlen = size; 227 req.newptr = data; 228 break; 229 case CTLTYPE_UINT: 230 if (getenv_array(path + rem, data, sizeof(data), &size, 231 sizeof(int), GETENV_UNSIGNED) == 0) 232 return; 233 req.newlen = size; 234 req.newptr = data; 235 break; 236 case CTLTYPE_LONG: 237 if (getenv_array(path + rem, data, sizeof(data), &size, 238 sizeof(long), GETENV_SIGNED) == 0) 239 return; 240 req.newlen = size; 241 req.newptr = data; 242 break; 243 case CTLTYPE_ULONG: 244 if (getenv_array(path + rem, data, sizeof(data), &size, 245 sizeof(long), GETENV_UNSIGNED) == 0) 246 return; 247 req.newlen = size; 248 req.newptr = data; 249 break; 250 case CTLTYPE_S8: 251 if (getenv_array(path + rem, data, sizeof(data), &size, 252 sizeof(int8_t), GETENV_SIGNED) == 0) 253 return; 254 req.newlen = size; 255 req.newptr = data; 256 break; 257 case CTLTYPE_S16: 258 if (getenv_array(path + rem, data, sizeof(data), &size, 259 sizeof(int16_t), GETENV_SIGNED) == 0) 260 return; 261 req.newlen = size; 262 req.newptr = data; 263 break; 264 case CTLTYPE_S32: 265 if (getenv_array(path + rem, data, sizeof(data), &size, 266 sizeof(int32_t), GETENV_SIGNED) == 0) 267 return; 268 req.newlen = size; 269 req.newptr = data; 270 break; 271 case CTLTYPE_S64: 272 if (getenv_array(path + rem, data, sizeof(data), &size, 273 sizeof(int64_t), GETENV_SIGNED) == 0) 274 return; 275 req.newlen = size; 276 req.newptr = data; 277 break; 278 case CTLTYPE_U8: 279 if (getenv_array(path + rem, data, sizeof(data), &size, 280 sizeof(uint8_t), GETENV_UNSIGNED) == 0) 281 return; 282 req.newlen = size; 283 req.newptr = data; 284 break; 285 case CTLTYPE_U16: 286 if (getenv_array(path + rem, data, sizeof(data), &size, 287 sizeof(uint16_t), GETENV_UNSIGNED) == 0) 288 return; 289 req.newlen = size; 290 req.newptr = data; 291 break; 292 case CTLTYPE_U32: 293 if (getenv_array(path + rem, data, sizeof(data), &size, 294 sizeof(uint32_t), GETENV_UNSIGNED) == 0) 295 return; 296 req.newlen = size; 297 req.newptr = data; 298 break; 299 case CTLTYPE_U64: 300 if (getenv_array(path + rem, data, sizeof(data), &size, 301 sizeof(uint64_t), GETENV_UNSIGNED) == 0) 302 return; 303 req.newlen = size; 304 req.newptr = data; 305 break; 306 case CTLTYPE_STRING: 307 penv = kern_getenv(path + rem); 308 if (penv == NULL) 309 return; 310 req.newlen = strlen(penv); 311 req.newptr = penv; 312 break; 313 default: 314 return; 315 } 316 error = sysctl_root_handler_locked(oidp, oidp->oid_arg1, 317 oidp->oid_arg2, &req, NULL); 318 if (error != 0) 319 printf("Setting sysctl %s failed: %d\n", path + rem, error); 320 if (penv != NULL) 321 freeenv(penv); 322} 323 324void 325sysctl_register_oid(struct sysctl_oid *oidp) 326{ 327 struct sysctl_oid_list *parent = oidp->oid_parent; 328 struct sysctl_oid *p; 329 struct sysctl_oid *q; 330 int oid_number; 331 int timeout = 2; 332 333 /* 334 * First check if another oid with the same name already 335 * exists in the parent's list. 336 */ 337 SYSCTL_ASSERT_WLOCKED(); 338 p = sysctl_find_oidname(oidp->oid_name, parent); 339 if (p != NULL) { 340 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 341 p->oid_refcnt++; 342 return; 343 } else { 344 printf("can't re-use a leaf (%s)!\n", p->oid_name); 345 return; 346 } 347 } 348 /* get current OID number */ 349 oid_number = oidp->oid_number; 350 351#if (OID_AUTO >= 0) 352#error "OID_AUTO is expected to be a negative value" 353#endif 354 /* 355 * Any negative OID number qualifies as OID_AUTO. Valid OID 356 * numbers should always be positive. 357 * 358 * NOTE: DO NOT change the starting value here, change it in 359 * <sys/sysctl.h>, and make sure it is at least 256 to 360 * accommodate e.g. net.inet.raw as a static sysctl node. 361 */ 362 if (oid_number < 0) { 363 static int newoid; 364 365 /* 366 * By decrementing the next OID number we spend less 367 * time inserting the OIDs into a sorted list. 368 */ 369 if (--newoid < CTL_AUTO_START) 370 newoid = 0x7fffffff; 371 372 oid_number = newoid; 373 } 374 375 /* 376 * Insert the OID into the parent's list sorted by OID number. 377 */ 378retry: 379 q = NULL; 380 SLIST_FOREACH(p, parent, oid_link) { 381 /* check if the current OID number is in use */ 382 if (oid_number == p->oid_number) { 383 /* get the next valid OID number */ 384 if (oid_number < CTL_AUTO_START || 385 oid_number == 0x7fffffff) { 386 /* wraparound - restart */ 387 oid_number = CTL_AUTO_START; 388 /* don't loop forever */ 389 if (!timeout--) 390 panic("sysctl: Out of OID numbers\n"); 391 goto retry; 392 } else { 393 oid_number++; 394 } 395 } else if (oid_number < p->oid_number) 396 break; 397 q = p; 398 } 399 /* check for non-auto OID number collision */ 400 if (oidp->oid_number >= 0 && oidp->oid_number < CTL_AUTO_START && 401 oid_number >= CTL_AUTO_START) { 402 printf("sysctl: OID number(%d) is already in use for '%s'\n", 403 oidp->oid_number, oidp->oid_name); 404 } 405 /* update the OID number, if any */ 406 oidp->oid_number = oid_number; 407 if (q != NULL) 408 SLIST_INSERT_AFTER(q, oidp, oid_link); 409 else 410 SLIST_INSERT_HEAD(parent, oidp, oid_link); 411 412 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE && 413#ifdef VIMAGE 414 (oidp->oid_kind & CTLFLAG_VNET) == 0 && 415#endif 416 (oidp->oid_kind & CTLFLAG_TUN) != 0 && 417 (oidp->oid_kind & CTLFLAG_NOFETCH) == 0) { 418 /* only fetch value once */ 419 oidp->oid_kind |= CTLFLAG_NOFETCH; 420 /* try to fetch value from kernel environment */ 421 sysctl_load_tunable_by_oid_locked(oidp); 422 } 423} 424 425void 426sysctl_register_disabled_oid(struct sysctl_oid *oidp) 427{ 428 429 /* 430 * Mark the leaf as dormant if it's not to be immediately enabled. 431 * We do not disable nodes as they can be shared between modules 432 * and it is always safe to access a node. 433 */ 434 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0, 435 ("internal flag is set in oid_kind")); 436 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 437 oidp->oid_kind |= CTLFLAG_DORMANT; 438 sysctl_register_oid(oidp); 439} 440 441void 442sysctl_enable_oid(struct sysctl_oid *oidp) 443{ 444 445 SYSCTL_ASSERT_WLOCKED(); 446 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 447 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0, 448 ("sysctl node is marked as dormant")); 449 return; 450 } 451 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) != 0, 452 ("enabling already enabled sysctl oid")); 453 oidp->oid_kind &= ~CTLFLAG_DORMANT; 454} 455 456void 457sysctl_unregister_oid(struct sysctl_oid *oidp) 458{ 459 struct sysctl_oid *p; 460 int error; 461 462 SYSCTL_ASSERT_WLOCKED(); 463 if (oidp->oid_number == OID_AUTO) { 464 error = EINVAL; 465 } else { 466 error = ENOENT; 467 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 468 if (p == oidp) { 469 SLIST_REMOVE(oidp->oid_parent, oidp, 470 sysctl_oid, oid_link); 471 error = 0; 472 break; 473 } 474 } 475 } 476 477 /* 478 * This can happen when a module fails to register and is 479 * being unloaded afterwards. It should not be a panic() 480 * for normal use. 481 */ 482 if (error) { 483 printf("%s: failed(%d) to unregister sysctl(%s)\n", 484 __func__, error, oidp->oid_name); 485 } 486} 487 488/* Initialize a new context to keep track of dynamically added sysctls. */ 489int 490sysctl_ctx_init(struct sysctl_ctx_list *c) 491{ 492 493 if (c == NULL) { 494 return (EINVAL); 495 } 496 497 /* 498 * No locking here, the caller is responsible for not adding 499 * new nodes to a context until after this function has 500 * returned. 501 */ 502 TAILQ_INIT(c); 503 return (0); 504} 505 506/* Free the context, and destroy all dynamic oids registered in this context */ 507int 508sysctl_ctx_free(struct sysctl_ctx_list *clist) 509{ 510 struct sysctl_ctx_entry *e, *e1; 511 int error; 512 513 error = 0; 514 /* 515 * First perform a "dry run" to check if it's ok to remove oids. 516 * XXX FIXME 517 * XXX This algorithm is a hack. But I don't know any 518 * XXX better solution for now... 519 */ 520 SYSCTL_WLOCK(); 521 TAILQ_FOREACH(e, clist, link) { 522 error = sysctl_remove_oid_locked(e->entry, 0, 0); 523 if (error) 524 break; 525 } 526 /* 527 * Restore deregistered entries, either from the end, 528 * or from the place where error occurred. 529 * e contains the entry that was not unregistered 530 */ 531 if (error) 532 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 533 else 534 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 535 while (e1 != NULL) { 536 sysctl_register_oid(e1->entry); 537 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 538 } 539 if (error) { 540 SYSCTL_WUNLOCK(); 541 return(EBUSY); 542 } 543 /* Now really delete the entries */ 544 e = TAILQ_FIRST(clist); 545 while (e != NULL) { 546 e1 = TAILQ_NEXT(e, link); 547 error = sysctl_remove_oid_locked(e->entry, 1, 0); 548 if (error) 549 panic("sysctl_remove_oid: corrupt tree, entry: %s", 550 e->entry->oid_name); 551 free(e, M_SYSCTLOID); 552 e = e1; 553 } 554 SYSCTL_WUNLOCK(); 555 return (error); 556} 557 558/* Add an entry to the context */ 559struct sysctl_ctx_entry * 560sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 561{ 562 struct sysctl_ctx_entry *e; 563 564 SYSCTL_ASSERT_WLOCKED(); 565 if (clist == NULL || oidp == NULL) 566 return(NULL); 567 e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 568 e->entry = oidp; 569 TAILQ_INSERT_HEAD(clist, e, link); 570 return (e); 571} 572 573/* Find an entry in the context */ 574struct sysctl_ctx_entry * 575sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 576{ 577 struct sysctl_ctx_entry *e; 578 579 SYSCTL_ASSERT_WLOCKED(); 580 if (clist == NULL || oidp == NULL) 581 return(NULL); 582 TAILQ_FOREACH(e, clist, link) { 583 if(e->entry == oidp) 584 return(e); 585 } 586 return (e); 587} 588 589/* 590 * Delete an entry from the context. 591 * NOTE: this function doesn't free oidp! You have to remove it 592 * with sysctl_remove_oid(). 593 */ 594int 595sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 596{ 597 struct sysctl_ctx_entry *e; 598 599 if (clist == NULL || oidp == NULL) 600 return (EINVAL); 601 SYSCTL_WLOCK(); 602 e = sysctl_ctx_entry_find(clist, oidp); 603 if (e != NULL) { 604 TAILQ_REMOVE(clist, e, link); 605 SYSCTL_WUNLOCK(); 606 free(e, M_SYSCTLOID); 607 return (0); 608 } else { 609 SYSCTL_WUNLOCK(); 610 return (ENOENT); 611 } 612} 613 614/* 615 * Remove dynamically created sysctl trees. 616 * oidp - top of the tree to be removed 617 * del - if 0 - just deregister, otherwise free up entries as well 618 * recurse - if != 0 traverse the subtree to be deleted 619 */ 620int 621sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 622{ 623 int error; 624 625 SYSCTL_WLOCK(); 626 error = sysctl_remove_oid_locked(oidp, del, recurse); 627 SYSCTL_WUNLOCK(); 628 return (error); 629} 630 631int 632sysctl_remove_name(struct sysctl_oid *parent, const char *name, 633 int del, int recurse) 634{ 635 struct sysctl_oid *p, *tmp; 636 int error; 637 638 error = ENOENT; 639 SYSCTL_WLOCK(); 640 SLIST_FOREACH_SAFE(p, SYSCTL_CHILDREN(parent), oid_link, tmp) { 641 if (strcmp(p->oid_name, name) == 0) { 642 error = sysctl_remove_oid_locked(p, del, recurse); 643 break; 644 } 645 } 646 SYSCTL_WUNLOCK(); 647 648 return (error); 649} 650 651 652static int 653sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse) 654{ 655 struct sysctl_oid *p, *tmp; 656 int error; 657 658 SYSCTL_ASSERT_WLOCKED(); 659 if (oidp == NULL) 660 return(EINVAL); 661 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 662 printf("Warning: can't remove non-dynamic nodes (%s)!\n", 663 oidp->oid_name); 664 return (EINVAL); 665 } 666 /* 667 * WARNING: normal method to do this should be through 668 * sysctl_ctx_free(). Use recursing as the last resort 669 * method to purge your sysctl tree of leftovers... 670 * However, if some other code still references these nodes, 671 * it will panic. 672 */ 673 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 674 if (oidp->oid_refcnt == 1) { 675 SLIST_FOREACH_SAFE(p, 676 SYSCTL_CHILDREN(oidp), oid_link, tmp) { 677 if (!recurse) { 678 printf("Warning: failed attempt to " 679 "remove oid %s with child %s\n", 680 oidp->oid_name, p->oid_name); 681 return (ENOTEMPTY); 682 } 683 error = sysctl_remove_oid_locked(p, del, 684 recurse); 685 if (error) 686 return (error); 687 } 688 } 689 } 690 if (oidp->oid_refcnt > 1 ) { 691 oidp->oid_refcnt--; 692 } else { 693 if (oidp->oid_refcnt == 0) { 694 printf("Warning: bad oid_refcnt=%u (%s)!\n", 695 oidp->oid_refcnt, oidp->oid_name); 696 return (EINVAL); 697 } 698 sysctl_unregister_oid(oidp); 699 if (del) { 700 /* 701 * Wait for all threads running the handler to drain. 702 * This preserves the previous behavior when the 703 * sysctl lock was held across a handler invocation, 704 * and is necessary for module unload correctness. 705 */ 706 while (oidp->oid_running > 0) { 707 oidp->oid_kind |= CTLFLAG_DYING; 708 SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0); 709 } 710 if (oidp->oid_descr) 711 free(__DECONST(char *, oidp->oid_descr), 712 M_SYSCTLOID); 713 free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); 714 free(oidp, M_SYSCTLOID); 715 } 716 } 717 return (0); 718} 719/* 720 * Create new sysctls at run time. 721 * clist may point to a valid context initialized with sysctl_ctx_init(). 722 */ 723struct sysctl_oid * 724sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 725 int number, const char *name, int kind, void *arg1, intmax_t arg2, 726 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr) 727{ 728 struct sysctl_oid *oidp; 729 730 /* You have to hook up somewhere.. */ 731 if (parent == NULL) 732 return(NULL); 733 /* Check if the node already exists, otherwise create it */ 734 SYSCTL_WLOCK(); 735 oidp = sysctl_find_oidname(name, parent); 736 if (oidp != NULL) { 737 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 738 oidp->oid_refcnt++; 739 /* Update the context */ 740 if (clist != NULL) 741 sysctl_ctx_entry_add(clist, oidp); 742 SYSCTL_WUNLOCK(); 743 return (oidp); 744 } else { 745 SYSCTL_WUNLOCK(); 746 printf("can't re-use a leaf (%s)!\n", name); 747 return (NULL); 748 } 749 } 750 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO); 751 oidp->oid_parent = parent; 752 SLIST_INIT(&oidp->oid_children); 753 oidp->oid_number = number; 754 oidp->oid_refcnt = 1; 755 oidp->oid_name = strdup(name, M_SYSCTLOID); 756 oidp->oid_handler = handler; 757 oidp->oid_kind = CTLFLAG_DYN | kind; 758 oidp->oid_arg1 = arg1; 759 oidp->oid_arg2 = arg2; 760 oidp->oid_fmt = fmt; 761 if (descr != NULL) 762 oidp->oid_descr = strdup(descr, M_SYSCTLOID); 763 /* Update the context, if used */ 764 if (clist != NULL) 765 sysctl_ctx_entry_add(clist, oidp); 766 /* Register this oid */ 767 sysctl_register_oid(oidp); 768 SYSCTL_WUNLOCK(); 769 return (oidp); 770} 771 772/* 773 * Rename an existing oid. 774 */ 775void 776sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) 777{ 778 char *newname; 779 char *oldname; 780 781 newname = strdup(name, M_SYSCTLOID); 782 SYSCTL_WLOCK(); 783 oldname = __DECONST(char *, oidp->oid_name); 784 oidp->oid_name = newname; 785 SYSCTL_WUNLOCK(); 786 free(oldname, M_SYSCTLOID); 787} 788 789/* 790 * Reparent an existing oid. 791 */ 792int 793sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent) 794{ 795 struct sysctl_oid *oidp; 796 797 SYSCTL_WLOCK(); 798 if (oid->oid_parent == parent) { 799 SYSCTL_WUNLOCK(); 800 return (0); 801 } 802 oidp = sysctl_find_oidname(oid->oid_name, parent); 803 if (oidp != NULL) { 804 SYSCTL_WUNLOCK(); 805 return (EEXIST); 806 } 807 sysctl_unregister_oid(oid); 808 oid->oid_parent = parent; 809 oid->oid_number = OID_AUTO; 810 sysctl_register_oid(oid); 811 SYSCTL_WUNLOCK(); 812 return (0); 813} 814 815/* 816 * Register the kernel's oids on startup. 817 */ 818SET_DECLARE(sysctl_set, struct sysctl_oid); 819 820static void 821sysctl_register_all(void *arg) 822{ 823 struct sysctl_oid **oidp; 824 825 sx_init(&sysctlmemlock, "sysctl mem"); 826 SYSCTL_INIT(); 827 SYSCTL_WLOCK(); 828 SET_FOREACH(oidp, sysctl_set) 829 sysctl_register_oid(*oidp); 830 SYSCTL_WUNLOCK(); 831} 832SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, NULL); 833 834/* 835 * "Staff-functions" 836 * 837 * These functions implement a presently undocumented interface 838 * used by the sysctl program to walk the tree, and get the type 839 * so it can print the value. 840 * This interface is under work and consideration, and should probably 841 * be killed with a big axe by the first person who can find the time. 842 * (be aware though, that the proper interface isn't as obvious as it 843 * may seem, there are various conflicting requirements. 844 * 845 * {0,0} printf the entire MIB-tree. 846 * {0,1,...} return the name of the "..." OID. 847 * {0,2,...} return the next OID. 848 * {0,3} return the OID of the name in "new" 849 * {0,4,...} return the kind & format info for the "..." OID. 850 * {0,5,...} return the description the "..." OID. 851 */ 852 853#ifdef SYSCTL_DEBUG 854static void 855sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 856{ 857 int k; 858 struct sysctl_oid *oidp; 859 860 SYSCTL_ASSERT_LOCKED(); 861 SLIST_FOREACH(oidp, l, oid_link) { 862 863 for (k=0; k<i; k++) 864 printf(" "); 865 866 printf("%d %s ", oidp->oid_number, oidp->oid_name); 867 868 printf("%c%c", 869 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 870 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 871 872 if (oidp->oid_handler) 873 printf(" *Handler"); 874 875 switch (oidp->oid_kind & CTLTYPE) { 876 case CTLTYPE_NODE: 877 printf(" Node\n"); 878 if (!oidp->oid_handler) { 879 sysctl_sysctl_debug_dump_node( 880 SYSCTL_CHILDREN(oidp), i + 2); 881 } 882 break; 883 case CTLTYPE_INT: printf(" Int\n"); break; 884 case CTLTYPE_UINT: printf(" u_int\n"); break; 885 case CTLTYPE_LONG: printf(" Long\n"); break; 886 case CTLTYPE_ULONG: printf(" u_long\n"); break; 887 case CTLTYPE_STRING: printf(" String\n"); break; 888 case CTLTYPE_S8: printf(" int8_t\n"); break; 889 case CTLTYPE_S16: printf(" int16_t\n"); break; 890 case CTLTYPE_S32: printf(" int32_t\n"); break; 891 case CTLTYPE_S64: printf(" int64_t\n"); break; 892 case CTLTYPE_U8: printf(" uint8_t\n"); break; 893 case CTLTYPE_U16: printf(" uint16_t\n"); break; 894 case CTLTYPE_U32: printf(" uint32_t\n"); break; 895 case CTLTYPE_U64: printf(" uint64_t\n"); break; 896 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; 897 default: printf("\n"); 898 } 899 900 } 901} 902 903static int 904sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 905{ 906 struct rm_priotracker tracker; 907 int error; 908 909 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 910 if (error) 911 return (error); 912 SYSCTL_RLOCK(&tracker); 913 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 914 SYSCTL_RUNLOCK(&tracker); 915 return (ENOENT); 916} 917 918SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD|CTLFLAG_MPSAFE, 919 0, 0, sysctl_sysctl_debug, "-", ""); 920#endif 921 922static int 923sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 924{ 925 int *name = (int *) arg1; 926 u_int namelen = arg2; 927 int error = 0; 928 struct sysctl_oid *oid; 929 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 930 struct rm_priotracker tracker; 931 char buf[10]; 932 933 SYSCTL_RLOCK(&tracker); 934 while (namelen) { 935 if (!lsp) { 936 snprintf(buf,sizeof(buf),"%d",*name); 937 if (req->oldidx) 938 error = SYSCTL_OUT(req, ".", 1); 939 if (!error) 940 error = SYSCTL_OUT(req, buf, strlen(buf)); 941 if (error) 942 goto out; 943 namelen--; 944 name++; 945 continue; 946 } 947 lsp2 = NULL; 948 SLIST_FOREACH(oid, lsp, oid_link) { 949 if (oid->oid_number != *name) 950 continue; 951 952 if (req->oldidx) 953 error = SYSCTL_OUT(req, ".", 1); 954 if (!error) 955 error = SYSCTL_OUT(req, oid->oid_name, 956 strlen(oid->oid_name)); 957 if (error) 958 goto out; 959 960 namelen--; 961 name++; 962 963 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 964 break; 965 966 if (oid->oid_handler) 967 break; 968 969 lsp2 = SYSCTL_CHILDREN(oid); 970 break; 971 } 972 lsp = lsp2; 973 } 974 error = SYSCTL_OUT(req, "", 1); 975 out: 976 SYSCTL_RUNLOCK(&tracker); 977 return (error); 978} 979 980/* 981 * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in 982 * capability mode. 983 */ 984static SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, 985 sysctl_sysctl_name, ""); 986 987static int 988sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 989 int *next, int *len, int level, struct sysctl_oid **oidpp) 990{ 991 struct sysctl_oid *oidp; 992 993 SYSCTL_ASSERT_LOCKED(); 994 *len = level; 995 SLIST_FOREACH(oidp, lsp, oid_link) { 996 *next = oidp->oid_number; 997 *oidpp = oidp; 998 999 if ((oidp->oid_kind & (CTLFLAG_SKIP | CTLFLAG_DORMANT)) != 0) 1000 continue; 1001 1002 if (!namelen) { 1003 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1004 return (0); 1005 if (oidp->oid_handler) 1006 /* We really should call the handler here...*/ 1007 return (0); 1008 lsp = SYSCTL_CHILDREN(oidp); 1009 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 1010 len, level+1, oidpp)) 1011 return (0); 1012 goto emptynode; 1013 } 1014 1015 if (oidp->oid_number < *name) 1016 continue; 1017 1018 if (oidp->oid_number > *name) { 1019 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1020 return (0); 1021 if (oidp->oid_handler) 1022 return (0); 1023 lsp = SYSCTL_CHILDREN(oidp); 1024 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 1025 next+1, len, level+1, oidpp)) 1026 return (0); 1027 goto next; 1028 } 1029 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1030 continue; 1031 1032 if (oidp->oid_handler) 1033 continue; 1034 1035 lsp = SYSCTL_CHILDREN(oidp); 1036 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 1037 len, level+1, oidpp)) 1038 return (0); 1039 next: 1040 namelen = 1; 1041 emptynode: 1042 *len = level; 1043 } 1044 return (1); 1045} 1046 1047static int 1048sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 1049{ 1050 int *name = (int *) arg1; 1051 u_int namelen = arg2; 1052 int i, j, error; 1053 struct sysctl_oid *oid; 1054 struct sysctl_oid_list *lsp = &sysctl__children; 1055 struct rm_priotracker tracker; 1056 int newoid[CTL_MAXNAME]; 1057 1058 SYSCTL_RLOCK(&tracker); 1059 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 1060 SYSCTL_RUNLOCK(&tracker); 1061 if (i) 1062 return (ENOENT); 1063 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 1064 return (error); 1065} 1066 1067/* 1068 * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in 1069 * capability mode. 1070 */ 1071static SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, 1072 sysctl_sysctl_next, ""); 1073 1074static int 1075name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) 1076{ 1077 struct sysctl_oid *oidp; 1078 struct sysctl_oid_list *lsp = &sysctl__children; 1079 char *p; 1080 1081 SYSCTL_ASSERT_LOCKED(); 1082 1083 for (*len = 0; *len < CTL_MAXNAME;) { 1084 p = strsep(&name, "."); 1085 1086 oidp = SLIST_FIRST(lsp); 1087 for (;; oidp = SLIST_NEXT(oidp, oid_link)) { 1088 if (oidp == NULL) 1089 return (ENOENT); 1090 if (strcmp(p, oidp->oid_name) == 0) 1091 break; 1092 } 1093 *oid++ = oidp->oid_number; 1094 (*len)++; 1095 1096 if (name == NULL || *name == '\0') { 1097 if (oidpp) 1098 *oidpp = oidp; 1099 return (0); 1100 } 1101 1102 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1103 break; 1104 1105 if (oidp->oid_handler) 1106 break; 1107 1108 lsp = SYSCTL_CHILDREN(oidp); 1109 } 1110 return (ENOENT); 1111} 1112 1113static int 1114sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 1115{ 1116 char *p; 1117 int error, oid[CTL_MAXNAME], len = 0; 1118 struct sysctl_oid *op = NULL; 1119 struct rm_priotracker tracker; 1120 char buf[32]; 1121 1122 if (!req->newlen) 1123 return (ENOENT); 1124 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 1125 return (ENAMETOOLONG); 1126 1127 p = buf; 1128 if (req->newlen >= sizeof(buf)) 1129 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); 1130 1131 error = SYSCTL_IN(req, p, req->newlen); 1132 if (error) { 1133 if (p != buf) 1134 free(p, M_SYSCTL); 1135 return (error); 1136 } 1137 1138 p [req->newlen] = '\0'; 1139 1140 SYSCTL_RLOCK(&tracker); 1141 error = name2oid(p, oid, &len, &op); 1142 SYSCTL_RUNLOCK(&tracker); 1143 1144 if (p != buf) 1145 free(p, M_SYSCTL); 1146 1147 if (error) 1148 return (error); 1149 1150 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 1151 return (error); 1152} 1153 1154/* 1155 * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in 1156 * capability mode. 1157 */ 1158SYSCTL_PROC(_sysctl, 3, name2oid, 1159 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_ANYBODY | CTLFLAG_MPSAFE 1160 | CTLFLAG_CAPRW, 0, 0, sysctl_sysctl_name2oid, "I", ""); 1161 1162static int 1163sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 1164{ 1165 struct sysctl_oid *oid; 1166 struct rm_priotracker tracker; 1167 int error; 1168 1169 SYSCTL_RLOCK(&tracker); 1170 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1171 if (error) 1172 goto out; 1173 1174 if (oid->oid_fmt == NULL) { 1175 error = ENOENT; 1176 goto out; 1177 } 1178 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 1179 if (error) 1180 goto out; 1181 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 1182 out: 1183 SYSCTL_RUNLOCK(&tracker); 1184 return (error); 1185} 1186 1187 1188static SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLFLAG_CAPRD, 1189 sysctl_sysctl_oidfmt, ""); 1190 1191static int 1192sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 1193{ 1194 struct sysctl_oid *oid; 1195 struct rm_priotracker tracker; 1196 int error; 1197 1198 SYSCTL_RLOCK(&tracker); 1199 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1200 if (error) 1201 goto out; 1202 1203 if (oid->oid_descr == NULL) { 1204 error = ENOENT; 1205 goto out; 1206 } 1207 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 1208 out: 1209 SYSCTL_RUNLOCK(&tracker); 1210 return (error); 1211} 1212 1213static SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLFLAG_CAPRD, 1214 sysctl_sysctl_oiddescr, ""); 1215 1216/* 1217 * Default "handler" functions. 1218 */ 1219 1220/* 1221 * Handle a bool. 1222 * Two cases: 1223 * a variable: point arg1 at it. 1224 * a constant: pass it in arg2. 1225 */ 1226 1227int 1228sysctl_handle_bool(SYSCTL_HANDLER_ARGS) 1229{ 1230 uint8_t temp; 1231 int error; 1232 1233 /* 1234 * Attempt to get a coherent snapshot by making a copy of the data. 1235 */ 1236 if (arg1) 1237 temp = *(bool *)arg1 ? 1 : 0; 1238 else 1239 temp = arg2 ? 1 : 0; 1240 1241 error = SYSCTL_OUT(req, &temp, sizeof(temp)); 1242 if (error || !req->newptr) 1243 return (error); 1244 1245 if (!arg1) 1246 error = EPERM; 1247 else { 1248 error = SYSCTL_IN(req, &temp, sizeof(temp)); 1249 if (!error) 1250 *(bool *)arg1 = temp ? 1 : 0; 1251 } 1252 return (error); 1253} 1254 1255/* 1256 * Handle an int8_t, signed or unsigned. 1257 * Two cases: 1258 * a variable: point arg1 at it. 1259 * a constant: pass it in arg2. 1260 */ 1261 1262int 1263sysctl_handle_8(SYSCTL_HANDLER_ARGS) 1264{ 1265 int8_t tmpout; 1266 int error = 0; 1267 1268 /* 1269 * Attempt to get a coherent snapshot by making a copy of the data. 1270 */ 1271 if (arg1) 1272 tmpout = *(int8_t *)arg1; 1273 else 1274 tmpout = arg2; 1275 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1276 1277 if (error || !req->newptr) 1278 return (error); 1279 1280 if (!arg1) 1281 error = EPERM; 1282 else 1283 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1284 return (error); 1285} 1286 1287/* 1288 * Handle an int16_t, signed or unsigned. 1289 * Two cases: 1290 * a variable: point arg1 at it. 1291 * a constant: pass it in arg2. 1292 */ 1293 1294int 1295sysctl_handle_16(SYSCTL_HANDLER_ARGS) 1296{ 1297 int16_t tmpout; 1298 int error = 0; 1299 1300 /* 1301 * Attempt to get a coherent snapshot by making a copy of the data. 1302 */ 1303 if (arg1) 1304 tmpout = *(int16_t *)arg1; 1305 else 1306 tmpout = arg2; 1307 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1308 1309 if (error || !req->newptr) 1310 return (error); 1311 1312 if (!arg1) 1313 error = EPERM; 1314 else 1315 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1316 return (error); 1317} 1318 1319/* 1320 * Handle an int32_t, signed or unsigned. 1321 * Two cases: 1322 * a variable: point arg1 at it. 1323 * a constant: pass it in arg2. 1324 */ 1325 1326int 1327sysctl_handle_32(SYSCTL_HANDLER_ARGS) 1328{ 1329 int32_t tmpout; 1330 int error = 0; 1331 1332 /* 1333 * Attempt to get a coherent snapshot by making a copy of the data. 1334 */ 1335 if (arg1) 1336 tmpout = *(int32_t *)arg1; 1337 else 1338 tmpout = arg2; 1339 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1340 1341 if (error || !req->newptr) 1342 return (error); 1343 1344 if (!arg1) 1345 error = EPERM; 1346 else 1347 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1348 return (error); 1349} 1350 1351/* 1352 * Handle an int, signed or unsigned. 1353 * Two cases: 1354 * a variable: point arg1 at it. 1355 * a constant: pass it in arg2. 1356 */ 1357 1358int 1359sysctl_handle_int(SYSCTL_HANDLER_ARGS) 1360{ 1361 int tmpout, error = 0; 1362 1363 /* 1364 * Attempt to get a coherent snapshot by making a copy of the data. 1365 */ 1366 if (arg1) 1367 tmpout = *(int *)arg1; 1368 else 1369 tmpout = arg2; 1370 error = SYSCTL_OUT(req, &tmpout, sizeof(int)); 1371 1372 if (error || !req->newptr) 1373 return (error); 1374 1375 if (!arg1) 1376 error = EPERM; 1377 else 1378 error = SYSCTL_IN(req, arg1, sizeof(int)); 1379 return (error); 1380} 1381 1382/* 1383 * Based on on sysctl_handle_int() convert milliseconds into ticks. 1384 * Note: this is used by TCP. 1385 */ 1386 1387int 1388sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) 1389{ 1390 int error, s, tt; 1391 1392 tt = *(int *)arg1; 1393 s = (int)((int64_t)tt * 1000 / hz); 1394 1395 error = sysctl_handle_int(oidp, &s, 0, req); 1396 if (error || !req->newptr) 1397 return (error); 1398 1399 tt = (int)((int64_t)s * hz / 1000); 1400 if (tt < 1) 1401 return (EINVAL); 1402 1403 *(int *)arg1 = tt; 1404 return (0); 1405} 1406 1407 1408/* 1409 * Handle a long, signed or unsigned. 1410 * Two cases: 1411 * a variable: point arg1 at it. 1412 * a constant: pass it in arg2. 1413 */ 1414 1415int 1416sysctl_handle_long(SYSCTL_HANDLER_ARGS) 1417{ 1418 int error = 0; 1419 long tmplong; 1420#ifdef SCTL_MASK32 1421 int tmpint; 1422#endif 1423 1424 /* 1425 * Attempt to get a coherent snapshot by making a copy of the data. 1426 */ 1427 if (arg1) 1428 tmplong = *(long *)arg1; 1429 else 1430 tmplong = arg2; 1431#ifdef SCTL_MASK32 1432 if (req->flags & SCTL_MASK32) { 1433 tmpint = tmplong; 1434 error = SYSCTL_OUT(req, &tmpint, sizeof(int)); 1435 } else 1436#endif 1437 error = SYSCTL_OUT(req, &tmplong, sizeof(long)); 1438 1439 if (error || !req->newptr) 1440 return (error); 1441 1442 if (!arg1) 1443 error = EPERM; 1444#ifdef SCTL_MASK32 1445 else if (req->flags & SCTL_MASK32) { 1446 error = SYSCTL_IN(req, &tmpint, sizeof(int)); 1447 *(long *)arg1 = (long)tmpint; 1448 } 1449#endif 1450 else 1451 error = SYSCTL_IN(req, arg1, sizeof(long)); 1452 return (error); 1453} 1454 1455/* 1456 * Handle a 64 bit int, signed or unsigned. 1457 * Two cases: 1458 * a variable: point arg1 at it. 1459 * a constant: pass it in arg2. 1460 */ 1461int 1462sysctl_handle_64(SYSCTL_HANDLER_ARGS) 1463{ 1464 int error = 0; 1465 uint64_t tmpout; 1466 1467 /* 1468 * Attempt to get a coherent snapshot by making a copy of the data. 1469 */ 1470 if (arg1) 1471 tmpout = *(uint64_t *)arg1; 1472 else 1473 tmpout = arg2; 1474 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t)); 1475 1476 if (error || !req->newptr) 1477 return (error); 1478 1479 if (!arg1) 1480 error = EPERM; 1481 else 1482 error = SYSCTL_IN(req, arg1, sizeof(uint64_t)); 1483 return (error); 1484} 1485 1486/* 1487 * Handle our generic '\0' terminated 'C' string. 1488 * Two cases: 1489 * a variable string: point arg1 at it, arg2 is max length. 1490 * a constant string: point arg1 at it, arg2 is zero. 1491 */ 1492 1493int 1494sysctl_handle_string(SYSCTL_HANDLER_ARGS) 1495{ 1496 size_t outlen; 1497 int error = 0, ro_string = 0; 1498 1499 /* 1500 * A zero-length buffer indicates a fixed size read-only 1501 * string: 1502 */ 1503 if (arg2 == 0) { 1504 arg2 = strlen((char *)arg1) + 1; 1505 ro_string = 1; 1506 } 1507 1508 if (req->oldptr != NULL) { 1509 char *tmparg; 1510 1511 if (ro_string) { 1512 tmparg = arg1; 1513 } else { 1514 /* try to make a coherent snapshot of the string */ 1515 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1516 memcpy(tmparg, arg1, arg2); 1517 } 1518 1519 outlen = strnlen(tmparg, arg2 - 1) + 1; 1520 error = SYSCTL_OUT(req, tmparg, outlen); 1521 1522 if (!ro_string) 1523 free(tmparg, M_SYSCTLTMP); 1524 } else { 1525 outlen = strnlen((char *)arg1, arg2 - 1) + 1; 1526 error = SYSCTL_OUT(req, NULL, outlen); 1527 } 1528 if (error || !req->newptr) 1529 return (error); 1530 1531 if ((req->newlen - req->newidx) >= arg2) { 1532 error = EINVAL; 1533 } else { 1534 arg2 = (req->newlen - req->newidx); 1535 error = SYSCTL_IN(req, arg1, arg2); 1536 ((char *)arg1)[arg2] = '\0'; 1537 } 1538 return (error); 1539} 1540 1541/* 1542 * Handle any kind of opaque data. 1543 * arg1 points to it, arg2 is the size. 1544 */ 1545 1546int 1547sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 1548{ 1549 int error, tries; 1550 u_int generation; 1551 struct sysctl_req req2; 1552 1553 /* 1554 * Attempt to get a coherent snapshot, by using the thread 1555 * pre-emption counter updated from within mi_switch() to 1556 * determine if we were pre-empted during a bcopy() or 1557 * copyout(). Make 3 attempts at doing this before giving up. 1558 * If we encounter an error, stop immediately. 1559 */ 1560 tries = 0; 1561 req2 = *req; 1562retry: 1563 generation = curthread->td_generation; 1564 error = SYSCTL_OUT(req, arg1, arg2); 1565 if (error) 1566 return (error); 1567 tries++; 1568 if (generation != curthread->td_generation && tries < 3) { 1569 *req = req2; 1570 goto retry; 1571 } 1572 1573 error = SYSCTL_IN(req, arg1, arg2); 1574 1575 return (error); 1576} 1577 1578/* 1579 * Convert seconds to a struct timeval. Intended for use with 1580 * intervals and thus does not permit negative seconds. 1581 */ 1582int 1583sysctl_sec_to_timeval(SYSCTL_HANDLER_ARGS) 1584{ 1585 struct timeval *tv; 1586 int error, secs; 1587 1588 tv = arg1; 1589 secs = tv->tv_sec; 1590 1591 error = sysctl_handle_int(oidp, &secs, 0, req); 1592 if (error || req->newptr == NULL) 1593 return (error); 1594 1595 if (secs < 0) 1596 return (EINVAL); 1597 tv->tv_sec = secs; 1598 1599 return (0); 1600} 1601 1602/* 1603 * Transfer functions to/from kernel space. 1604 * XXX: rather untested at this point 1605 */ 1606static int 1607sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 1608{ 1609 size_t i = 0; 1610 1611 if (req->oldptr) { 1612 i = l; 1613 if (req->oldlen <= req->oldidx) 1614 i = 0; 1615 else 1616 if (i > req->oldlen - req->oldidx) 1617 i = req->oldlen - req->oldidx; 1618 if (i > 0) 1619 bcopy(p, (char *)req->oldptr + req->oldidx, i); 1620 } 1621 req->oldidx += l; 1622 if (req->oldptr && i != l) 1623 return (ENOMEM); 1624 return (0); 1625} 1626 1627static int 1628sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 1629{ 1630 if (!req->newptr) 1631 return (0); 1632 if (req->newlen - req->newidx < l) 1633 return (EINVAL); 1634 bcopy((char *)req->newptr + req->newidx, p, l); 1635 req->newidx += l; 1636 return (0); 1637} 1638 1639int 1640kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1641 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) 1642{ 1643 int error = 0; 1644 struct sysctl_req req; 1645 1646 bzero(&req, sizeof req); 1647 1648 req.td = td; 1649 req.flags = flags; 1650 1651 if (oldlenp) { 1652 req.oldlen = *oldlenp; 1653 } 1654 req.validlen = req.oldlen; 1655 1656 if (old) { 1657 req.oldptr= old; 1658 } 1659 1660 if (new != NULL) { 1661 req.newlen = newlen; 1662 req.newptr = new; 1663 } 1664 1665 req.oldfunc = sysctl_old_kernel; 1666 req.newfunc = sysctl_new_kernel; 1667 req.lock = REQ_UNWIRED; 1668 1669 error = sysctl_root(0, name, namelen, &req); 1670 1671 if (req.lock == REQ_WIRED && req.validlen > 0) 1672 vsunlock(req.oldptr, req.validlen); 1673 1674 if (error && error != ENOMEM) 1675 return (error); 1676 1677 if (retval) { 1678 if (req.oldptr && req.oldidx > req.validlen) 1679 *retval = req.validlen; 1680 else 1681 *retval = req.oldidx; 1682 } 1683 return (error); 1684} 1685 1686int 1687kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp, 1688 void *new, size_t newlen, size_t *retval, int flags) 1689{ 1690 int oid[CTL_MAXNAME]; 1691 size_t oidlen, plen; 1692 int error; 1693 1694 oid[0] = 0; /* sysctl internal magic */ 1695 oid[1] = 3; /* name2oid */ 1696 oidlen = sizeof(oid); 1697 1698 error = kernel_sysctl(td, oid, 2, oid, &oidlen, 1699 (void *)name, strlen(name), &plen, flags); 1700 if (error) 1701 return (error); 1702 1703 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp, 1704 new, newlen, retval, flags); 1705 return (error); 1706} 1707 1708/* 1709 * Transfer function to/from user space. 1710 */ 1711static int 1712sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1713{ 1714 size_t i, len, origidx; 1715 int error; 1716 1717 origidx = req->oldidx; 1718 req->oldidx += l; 1719 if (req->oldptr == NULL) 1720 return (0); 1721 /* 1722 * If we have not wired the user supplied buffer and we are currently 1723 * holding locks, drop a witness warning, as it's possible that 1724 * write operations to the user page can sleep. 1725 */ 1726 if (req->lock != REQ_WIRED) 1727 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1728 "sysctl_old_user()"); 1729 i = l; 1730 len = req->validlen; 1731 if (len <= origidx) 1732 i = 0; 1733 else { 1734 if (i > len - origidx) 1735 i = len - origidx; 1736 if (req->lock == REQ_WIRED) { 1737 error = copyout_nofault(p, (char *)req->oldptr + 1738 origidx, i); 1739 } else 1740 error = copyout(p, (char *)req->oldptr + origidx, i); 1741 if (error != 0) 1742 return (error); 1743 } 1744 if (i < l) 1745 return (ENOMEM); 1746 return (0); 1747} 1748 1749static int 1750sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1751{ 1752 int error; 1753 1754 if (!req->newptr) 1755 return (0); 1756 if (req->newlen - req->newidx < l) 1757 return (EINVAL); 1758 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1759 "sysctl_new_user()"); 1760 error = copyin((char *)req->newptr + req->newidx, p, l); 1761 req->newidx += l; 1762 return (error); 1763} 1764 1765/* 1766 * Wire the user space destination buffer. If set to a value greater than 1767 * zero, the len parameter limits the maximum amount of wired memory. 1768 */ 1769int 1770sysctl_wire_old_buffer(struct sysctl_req *req, size_t len) 1771{ 1772 int ret; 1773 size_t wiredlen; 1774 1775 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen; 1776 ret = 0; 1777 if (req->lock != REQ_WIRED && req->oldptr && 1778 req->oldfunc == sysctl_old_user) { 1779 if (wiredlen != 0) { 1780 ret = vslock(req->oldptr, wiredlen); 1781 if (ret != 0) { 1782 if (ret != ENOMEM) 1783 return (ret); 1784 wiredlen = 0; 1785 } 1786 } 1787 req->lock = REQ_WIRED; 1788 req->validlen = wiredlen; 1789 } 1790 return (0); 1791} 1792 1793int 1794sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 1795 int *nindx, struct sysctl_req *req) 1796{ 1797 struct sysctl_oid_list *lsp; 1798 struct sysctl_oid *oid; 1799 int indx; 1800 1801 SYSCTL_ASSERT_LOCKED(); 1802 lsp = &sysctl__children; 1803 indx = 0; 1804 while (indx < CTL_MAXNAME) { 1805 SLIST_FOREACH(oid, lsp, oid_link) { 1806 if (oid->oid_number == name[indx]) 1807 break; 1808 } 1809 if (oid == NULL) 1810 return (ENOENT); 1811 1812 indx++; 1813 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1814 if (oid->oid_handler != NULL || indx == namelen) { 1815 *noid = oid; 1816 if (nindx != NULL) 1817 *nindx = indx; 1818 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 1819 ("%s found DYING node %p", __func__, oid)); 1820 return (0); 1821 } 1822 lsp = SYSCTL_CHILDREN(oid); 1823 } else if (indx == namelen) { 1824 if ((oid->oid_kind & CTLFLAG_DORMANT) != 0) 1825 return (ENOENT); 1826 *noid = oid; 1827 if (nindx != NULL) 1828 *nindx = indx; 1829 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 1830 ("%s found DYING node %p", __func__, oid)); 1831 return (0); 1832 } else { 1833 return (ENOTDIR); 1834 } 1835 } 1836 return (ENOENT); 1837} 1838 1839/* 1840 * Traverse our tree, and find the right node, execute whatever it points 1841 * to, and return the resulting error code. 1842 */ 1843 1844static int 1845sysctl_root(SYSCTL_HANDLER_ARGS) 1846{ 1847 struct sysctl_oid *oid; 1848 struct rm_priotracker tracker; 1849 int error, indx, lvl; 1850 1851 SYSCTL_RLOCK(&tracker); 1852 1853 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 1854 if (error) 1855 goto out; 1856 1857 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1858 /* 1859 * You can't call a sysctl when it's a node, but has 1860 * no handler. Inform the user that it's a node. 1861 * The indx may or may not be the same as namelen. 1862 */ 1863 if (oid->oid_handler == NULL) { 1864 error = EISDIR; 1865 goto out; 1866 } 1867 } 1868 1869 /* Is this sysctl writable? */ 1870 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) { 1871 error = EPERM; 1872 goto out; 1873 } 1874 1875 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL")); 1876 1877#ifdef CAPABILITY_MODE 1878 /* 1879 * If the process is in capability mode, then don't permit reading or 1880 * writing unless specifically granted for the node. 1881 */ 1882 if (IN_CAPABILITY_MODE(req->td)) { 1883 if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) || 1884 (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) { 1885 error = EPERM; 1886 goto out; 1887 } 1888 } 1889#endif 1890 1891 /* Is this sysctl sensitive to securelevels? */ 1892 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) { 1893 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE; 1894 error = securelevel_gt(req->td->td_ucred, lvl); 1895 if (error) 1896 goto out; 1897 } 1898 1899 /* Is this sysctl writable by only privileged users? */ 1900 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) { 1901 int priv; 1902 1903 if (oid->oid_kind & CTLFLAG_PRISON) 1904 priv = PRIV_SYSCTL_WRITEJAIL; 1905#ifdef VIMAGE 1906 else if ((oid->oid_kind & CTLFLAG_VNET) && 1907 prison_owns_vnet(req->td->td_ucred)) 1908 priv = PRIV_SYSCTL_WRITEJAIL; 1909#endif 1910 else 1911 priv = PRIV_SYSCTL_WRITE; 1912 error = priv_check(req->td, priv); 1913 if (error) 1914 goto out; 1915 } 1916 1917 if (!oid->oid_handler) { 1918 error = EINVAL; 1919 goto out; 1920 } 1921 1922 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1923 arg1 = (int *)arg1 + indx; 1924 arg2 -= indx; 1925 } else { 1926 arg1 = oid->oid_arg1; 1927 arg2 = oid->oid_arg2; 1928 } 1929#ifdef MAC 1930 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2, 1931 req); 1932 if (error != 0) 1933 goto out; 1934#endif 1935#ifdef VIMAGE 1936 if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL) 1937 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1); 1938#endif 1939 error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker); 1940 1941out: 1942 SYSCTL_RUNLOCK(&tracker); 1943 return (error); 1944} 1945 1946#ifndef _SYS_SYSPROTO_H_ 1947struct sysctl_args { 1948 int *name; 1949 u_int namelen; 1950 void *old; 1951 size_t *oldlenp; 1952 void *new; 1953 size_t newlen; 1954}; 1955#endif 1956int 1957sys___sysctl(struct thread *td, struct sysctl_args *uap) 1958{ 1959 int error, i, name[CTL_MAXNAME]; 1960 size_t j; 1961 1962 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 1963 return (EINVAL); 1964 1965 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 1966 if (error) 1967 return (error); 1968 1969 error = userland_sysctl(td, name, uap->namelen, 1970 uap->old, uap->oldlenp, 0, 1971 uap->new, uap->newlen, &j, 0); 1972 if (error && error != ENOMEM) 1973 return (error); 1974 if (uap->oldlenp) { 1975 i = copyout(&j, uap->oldlenp, sizeof(j)); 1976 if (i) 1977 return (i); 1978 } 1979 return (error); 1980} 1981 1982/* 1983 * This is used from various compatibility syscalls too. That's why name 1984 * must be in kernel space. 1985 */ 1986int 1987userland_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1988 size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval, 1989 int flags) 1990{ 1991 int error = 0, memlocked; 1992 struct sysctl_req req; 1993 1994 bzero(&req, sizeof req); 1995 1996 req.td = td; 1997 req.flags = flags; 1998 1999 if (oldlenp) { 2000 if (inkernel) { 2001 req.oldlen = *oldlenp; 2002 } else { 2003 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 2004 if (error) 2005 return (error); 2006 } 2007 } 2008 req.validlen = req.oldlen; 2009 req.oldptr = old; 2010 2011 if (new != NULL) { 2012 req.newlen = newlen; 2013 req.newptr = new; 2014 } 2015 2016 req.oldfunc = sysctl_old_user; 2017 req.newfunc = sysctl_new_user; 2018 req.lock = REQ_UNWIRED; 2019 2020#ifdef KTRACE 2021 if (KTRPOINT(curthread, KTR_SYSCTL)) 2022 ktrsysctl(name, namelen); 2023#endif 2024 2025 if (req.oldptr && req.oldlen > PAGE_SIZE) { 2026 memlocked = 1; 2027 sx_xlock(&sysctlmemlock); 2028 } else 2029 memlocked = 0; 2030 CURVNET_SET(TD_TO_VNET(td)); 2031 2032 for (;;) { 2033 req.oldidx = 0; 2034 req.newidx = 0; 2035 error = sysctl_root(0, name, namelen, &req); 2036 if (error != EAGAIN) 2037 break; 2038 kern_yield(PRI_USER); 2039 } 2040 2041 CURVNET_RESTORE(); 2042 2043 if (req.lock == REQ_WIRED && req.validlen > 0) 2044 vsunlock(req.oldptr, req.validlen); 2045 if (memlocked) 2046 sx_xunlock(&sysctlmemlock); 2047 2048 if (error && error != ENOMEM) 2049 return (error); 2050 2051 if (retval) { 2052 if (req.oldptr && req.oldidx > req.validlen) 2053 *retval = req.validlen; 2054 else 2055 *retval = req.oldidx; 2056 } 2057 return (error); 2058} 2059 2060/* 2061 * Drain into a sysctl struct. The user buffer should be wired if a page 2062 * fault would cause issue. 2063 */ 2064static int 2065sbuf_sysctl_drain(void *arg, const char *data, int len) 2066{ 2067 struct sysctl_req *req = arg; 2068 int error; 2069 2070 error = SYSCTL_OUT(req, data, len); 2071 KASSERT(error >= 0, ("Got unexpected negative value %d", error)); 2072 return (error == 0 ? len : -error); 2073} 2074 2075struct sbuf * 2076sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, 2077 struct sysctl_req *req) 2078{ 2079 2080 /* Supply a default buffer size if none given. */ 2081 if (buf == NULL && length == 0) 2082 length = 64; 2083 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL); 2084 sbuf_set_drain(s, sbuf_sysctl_drain, req); 2085 return (s); 2086} 2087