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 /* 88 * The sysctllock protects the MIB tree. It also protects sysctl 89 * contexts used with dynamic sysctls. The sysctl_register_oid() and 90 * sysctl_unregister_oid() routines require the sysctllock to already 91 * be held, so the sysctl_wlock() and sysctl_wunlock() routines are 92 * provided for the few places in the kernel which need to use that 93 * API rather than using the dynamic API. Use of the dynamic API is 94 * strongly encouraged for most code. 95 * 96 * The sysctlmemlock is used to limit the amount of user memory wired for 97 * sysctl requests. This is implemented by serializing any userland 98 * sysctl requests larger than a single page via an exclusive lock. 99 * 100 * The sysctlstringlock is used to protect concurrent access to writable 101 * string nodes in sysctl_handle_string(). 102 */ 103 static struct rmlock sysctllock; 104 static struct sx __exclusive_cache_line sysctlmemlock; 105 static struct sx sysctlstringlock; 106 107 #define SYSCTL_WLOCK() rm_wlock(&sysctllock) 108 #define SYSCTL_WUNLOCK() rm_wunlock(&sysctllock) 109 #define SYSCTL_RLOCK(tracker) rm_rlock(&sysctllock, (tracker)) 110 #define SYSCTL_RUNLOCK(tracker) rm_runlock(&sysctllock, (tracker)) 111 #define SYSCTL_WLOCKED() rm_wowned(&sysctllock) 112 #define SYSCTL_ASSERT_LOCKED() rm_assert(&sysctllock, RA_LOCKED) 113 #define SYSCTL_ASSERT_WLOCKED() rm_assert(&sysctllock, RA_WLOCKED) 114 #define SYSCTL_ASSERT_RLOCKED() rm_assert(&sysctllock, RA_RLOCKED) 115 #define SYSCTL_INIT() rm_init_flags(&sysctllock, "sysctl lock", \ 116 RM_SLEEPABLE) 117 #define SYSCTL_SLEEP(ch, wmesg, timo) \ 118 rm_sleep(ch, &sysctllock, 0, wmesg, timo) 119 120 static int sysctl_root(SYSCTL_HANDLER_ARGS); 121 122 /* Root list */ 123 struct sysctl_oid_list sysctl__children = SLIST_HEAD_INITIALIZER(&sysctl__children); 124 125 static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, 126 int recurse); 127 static int sysctl_old_kernel(struct sysctl_req *, const void *, size_t); 128 static int sysctl_new_kernel(struct sysctl_req *, void *, size_t); 129 130 static struct sysctl_oid * 131 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list) 132 { 133 struct sysctl_oid *oidp; 134 135 SYSCTL_ASSERT_LOCKED(); 136 SLIST_FOREACH(oidp, list, oid_link) { 137 if (strcmp(oidp->oid_name, name) == 0) { 138 return (oidp); 139 } 140 } 141 return (NULL); 142 } 143 144 /* 145 * Initialization of the MIB tree. 146 * 147 * Order by number in each list. 148 */ 149 void 150 sysctl_wlock(void) 151 { 152 153 SYSCTL_WLOCK(); 154 } 155 156 void 157 sysctl_wunlock(void) 158 { 159 160 SYSCTL_WUNLOCK(); 161 } 162 163 static int 164 sysctl_root_handler_locked(struct sysctl_oid *oid, void *arg1, intmax_t arg2, 165 struct sysctl_req *req, struct rm_priotracker *tracker) 166 { 167 int error; 168 169 if (oid->oid_kind & CTLFLAG_DYN) 170 atomic_add_int(&oid->oid_running, 1); 171 172 if (tracker != NULL) 173 SYSCTL_RUNLOCK(tracker); 174 else 175 SYSCTL_WUNLOCK(); 176 177 /* 178 * Treat set CTLFLAG_NEEDGIANT and unset CTLFLAG_MPSAFE flags the same, 179 * untill we're ready to remove all traces of Giant from sysctl(9). 180 */ 181 if ((oid->oid_kind & CTLFLAG_NEEDGIANT) || 182 (!(oid->oid_kind & CTLFLAG_MPSAFE))) 183 mtx_lock(&Giant); 184 error = oid->oid_handler(oid, arg1, arg2, req); 185 if ((oid->oid_kind & CTLFLAG_NEEDGIANT) || 186 (!(oid->oid_kind & CTLFLAG_MPSAFE))) 187 mtx_unlock(&Giant); 188 189 KFAIL_POINT_ERROR(_debug_fail_point, sysctl_running, error); 190 191 if (tracker != NULL) 192 SYSCTL_RLOCK(tracker); 193 else 194 SYSCTL_WLOCK(); 195 196 if (oid->oid_kind & CTLFLAG_DYN) { 197 if (atomic_fetchadd_int(&oid->oid_running, -1) == 1 && 198 (oid->oid_kind & CTLFLAG_DYING) != 0) 199 wakeup(&oid->oid_running); 200 } 201 202 return (error); 203 } 204 205 static void 206 sysctl_load_tunable_by_oid_locked(struct sysctl_oid *oidp) 207 { 208 struct sysctl_req req; 209 struct sysctl_oid *curr; 210 char *penv = NULL; 211 char path[96]; 212 ssize_t rem = sizeof(path); 213 ssize_t len; 214 uint8_t data[512] __aligned(sizeof(uint64_t)); 215 int size; 216 int error; 217 218 path[--rem] = 0; 219 220 for (curr = oidp; curr != NULL; curr = SYSCTL_PARENT(curr)) { 221 len = strlen(curr->oid_name); 222 rem -= len; 223 if (curr != oidp) 224 rem -= 1; 225 if (rem < 0) { 226 printf("OID path exceeds %d bytes\n", (int)sizeof(path)); 227 return; 228 } 229 memcpy(path + rem, curr->oid_name, len); 230 if (curr != oidp) 231 path[rem + len] = '.'; 232 } 233 234 memset(&req, 0, sizeof(req)); 235 236 req.td = curthread; 237 req.oldfunc = sysctl_old_kernel; 238 req.newfunc = sysctl_new_kernel; 239 req.lock = REQ_UNWIRED; 240 241 switch (oidp->oid_kind & CTLTYPE) { 242 case CTLTYPE_INT: 243 if (getenv_array(path + rem, data, sizeof(data), &size, 244 sizeof(int), GETENV_SIGNED) == 0) 245 return; 246 req.newlen = size; 247 req.newptr = data; 248 break; 249 case CTLTYPE_UINT: 250 if (getenv_array(path + rem, data, sizeof(data), &size, 251 sizeof(int), GETENV_UNSIGNED) == 0) 252 return; 253 req.newlen = size; 254 req.newptr = data; 255 break; 256 case CTLTYPE_LONG: 257 if (getenv_array(path + rem, data, sizeof(data), &size, 258 sizeof(long), GETENV_SIGNED) == 0) 259 return; 260 req.newlen = size; 261 req.newptr = data; 262 break; 263 case CTLTYPE_ULONG: 264 if (getenv_array(path + rem, data, sizeof(data), &size, 265 sizeof(long), GETENV_UNSIGNED) == 0) 266 return; 267 req.newlen = size; 268 req.newptr = data; 269 break; 270 case CTLTYPE_S8: 271 if (getenv_array(path + rem, data, sizeof(data), &size, 272 sizeof(int8_t), GETENV_SIGNED) == 0) 273 return; 274 req.newlen = size; 275 req.newptr = data; 276 break; 277 case CTLTYPE_S16: 278 if (getenv_array(path + rem, data, sizeof(data), &size, 279 sizeof(int16_t), GETENV_SIGNED) == 0) 280 return; 281 req.newlen = size; 282 req.newptr = data; 283 break; 284 case CTLTYPE_S32: 285 if (getenv_array(path + rem, data, sizeof(data), &size, 286 sizeof(int32_t), GETENV_SIGNED) == 0) 287 return; 288 req.newlen = size; 289 req.newptr = data; 290 break; 291 case CTLTYPE_S64: 292 if (getenv_array(path + rem, data, sizeof(data), &size, 293 sizeof(int64_t), GETENV_SIGNED) == 0) 294 return; 295 req.newlen = size; 296 req.newptr = data; 297 break; 298 case CTLTYPE_U8: 299 if (getenv_array(path + rem, data, sizeof(data), &size, 300 sizeof(uint8_t), GETENV_UNSIGNED) == 0) 301 return; 302 req.newlen = size; 303 req.newptr = data; 304 break; 305 case CTLTYPE_U16: 306 if (getenv_array(path + rem, data, sizeof(data), &size, 307 sizeof(uint16_t), GETENV_UNSIGNED) == 0) 308 return; 309 req.newlen = size; 310 req.newptr = data; 311 break; 312 case CTLTYPE_U32: 313 if (getenv_array(path + rem, data, sizeof(data), &size, 314 sizeof(uint32_t), GETENV_UNSIGNED) == 0) 315 return; 316 req.newlen = size; 317 req.newptr = data; 318 break; 319 case CTLTYPE_U64: 320 if (getenv_array(path + rem, data, sizeof(data), &size, 321 sizeof(uint64_t), GETENV_UNSIGNED) == 0) 322 return; 323 req.newlen = size; 324 req.newptr = data; 325 break; 326 case CTLTYPE_STRING: 327 penv = kern_getenv(path + rem); 328 if (penv == NULL) 329 return; 330 req.newlen = strlen(penv); 331 req.newptr = penv; 332 break; 333 default: 334 return; 335 } 336 error = sysctl_root_handler_locked(oidp, oidp->oid_arg1, 337 oidp->oid_arg2, &req, NULL); 338 if (error != 0) 339 printf("Setting sysctl %s failed: %d\n", path + rem, error); 340 if (penv != NULL) 341 freeenv(penv); 342 } 343 344 /* 345 * Locate the path to a given oid. Returns the length of the resulting path, 346 * or -1 if the oid was not found. nodes must have room for CTL_MAXNAME 347 * elements and be NULL initialized. 348 */ 349 static int 350 sysctl_search_oid(struct sysctl_oid **nodes, struct sysctl_oid *needle) 351 { 352 int indx; 353 354 SYSCTL_ASSERT_LOCKED(); 355 indx = 0; 356 while (indx < CTL_MAXNAME && indx >= 0) { 357 if (nodes[indx] == NULL && indx == 0) 358 nodes[indx] = SLIST_FIRST(&sysctl__children); 359 else if (nodes[indx] == NULL) 360 nodes[indx] = SLIST_FIRST(&nodes[indx - 1]->oid_children); 361 else 362 nodes[indx] = SLIST_NEXT(nodes[indx], oid_link); 363 364 if (nodes[indx] == needle) 365 return (indx + 1); 366 367 if (nodes[indx] == NULL) { 368 indx--; 369 continue; 370 } 371 372 if ((nodes[indx]->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 373 indx++; 374 continue; 375 } 376 } 377 return (-1); 378 } 379 380 static void 381 sysctl_warn_reuse(const char *func, struct sysctl_oid *leaf) 382 { 383 struct sysctl_oid *nodes[CTL_MAXNAME]; 384 char buf[128]; 385 struct sbuf sb; 386 int rc, i; 387 388 (void)sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN | SBUF_INCLUDENUL); 389 sbuf_set_drain(&sb, sbuf_printf_drain, NULL); 390 391 sbuf_printf(&sb, "%s: can't re-use a leaf (", __func__); 392 393 memset(nodes, 0, sizeof(nodes)); 394 rc = sysctl_search_oid(nodes, leaf); 395 if (rc > 0) { 396 for (i = 0; i < rc; i++) 397 sbuf_printf(&sb, "%s%.*s", nodes[i]->oid_name, 398 i != (rc - 1), "."); 399 } else { 400 sbuf_printf(&sb, "%s", leaf->oid_name); 401 } 402 sbuf_printf(&sb, ")!\n"); 403 404 (void)sbuf_finish(&sb); 405 } 406 407 #ifdef SYSCTL_DEBUG 408 static int 409 sysctl_reuse_test(SYSCTL_HANDLER_ARGS) 410 { 411 struct rm_priotracker tracker; 412 413 SYSCTL_RLOCK(&tracker); 414 sysctl_warn_reuse(__func__, oidp); 415 SYSCTL_RUNLOCK(&tracker); 416 return (0); 417 } 418 SYSCTL_PROC(_sysctl, OID_AUTO, reuse_test, 419 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, sysctl_reuse_test, "-", 420 ""); 421 #endif 422 423 void 424 sysctl_register_oid(struct sysctl_oid *oidp) 425 { 426 struct sysctl_oid_list *parent = oidp->oid_parent; 427 struct sysctl_oid *p; 428 struct sysctl_oid *q; 429 int oid_number; 430 int timeout = 2; 431 432 /* 433 * First check if another oid with the same name already 434 * exists in the parent's list. 435 */ 436 SYSCTL_ASSERT_WLOCKED(); 437 p = sysctl_find_oidname(oidp->oid_name, parent); 438 if (p != NULL) { 439 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 440 p->oid_refcnt++; 441 return; 442 } else { 443 sysctl_warn_reuse(__func__, p); 444 return; 445 } 446 } 447 /* get current OID number */ 448 oid_number = oidp->oid_number; 449 450 #if (OID_AUTO >= 0) 451 #error "OID_AUTO is expected to be a negative value" 452 #endif 453 /* 454 * Any negative OID number qualifies as OID_AUTO. Valid OID 455 * numbers should always be positive. 456 * 457 * NOTE: DO NOT change the starting value here, change it in 458 * <sys/sysctl.h>, and make sure it is at least 256 to 459 * accommodate e.g. net.inet.raw as a static sysctl node. 460 */ 461 if (oid_number < 0) { 462 static int newoid; 463 464 /* 465 * By decrementing the next OID number we spend less 466 * time inserting the OIDs into a sorted list. 467 */ 468 if (--newoid < CTL_AUTO_START) 469 newoid = 0x7fffffff; 470 471 oid_number = newoid; 472 } 473 474 /* 475 * Insert the OID into the parent's list sorted by OID number. 476 */ 477 retry: 478 q = NULL; 479 SLIST_FOREACH(p, parent, oid_link) { 480 /* check if the current OID number is in use */ 481 if (oid_number == p->oid_number) { 482 /* get the next valid OID number */ 483 if (oid_number < CTL_AUTO_START || 484 oid_number == 0x7fffffff) { 485 /* wraparound - restart */ 486 oid_number = CTL_AUTO_START; 487 /* don't loop forever */ 488 if (!timeout--) 489 panic("sysctl: Out of OID numbers\n"); 490 goto retry; 491 } else { 492 oid_number++; 493 } 494 } else if (oid_number < p->oid_number) 495 break; 496 q = p; 497 } 498 /* check for non-auto OID number collision */ 499 if (oidp->oid_number >= 0 && oidp->oid_number < CTL_AUTO_START && 500 oid_number >= CTL_AUTO_START) { 501 printf("sysctl: OID number(%d) is already in use for '%s'\n", 502 oidp->oid_number, oidp->oid_name); 503 } 504 /* update the OID number, if any */ 505 oidp->oid_number = oid_number; 506 if (q != NULL) 507 SLIST_INSERT_AFTER(q, oidp, oid_link); 508 else 509 SLIST_INSERT_HEAD(parent, oidp, oid_link); 510 511 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE && 512 #ifdef VIMAGE 513 (oidp->oid_kind & CTLFLAG_VNET) == 0 && 514 #endif 515 (oidp->oid_kind & CTLFLAG_TUN) != 0 && 516 (oidp->oid_kind & CTLFLAG_NOFETCH) == 0) { 517 /* only fetch value once */ 518 oidp->oid_kind |= CTLFLAG_NOFETCH; 519 /* try to fetch value from kernel environment */ 520 sysctl_load_tunable_by_oid_locked(oidp); 521 } 522 } 523 524 void 525 sysctl_register_disabled_oid(struct sysctl_oid *oidp) 526 { 527 528 /* 529 * Mark the leaf as dormant if it's not to be immediately enabled. 530 * We do not disable nodes as they can be shared between modules 531 * and it is always safe to access a node. 532 */ 533 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0, 534 ("internal flag is set in oid_kind")); 535 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 536 oidp->oid_kind |= CTLFLAG_DORMANT; 537 sysctl_register_oid(oidp); 538 } 539 540 void 541 sysctl_enable_oid(struct sysctl_oid *oidp) 542 { 543 544 SYSCTL_ASSERT_WLOCKED(); 545 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 546 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0, 547 ("sysctl node is marked as dormant")); 548 return; 549 } 550 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) != 0, 551 ("enabling already enabled sysctl oid")); 552 oidp->oid_kind &= ~CTLFLAG_DORMANT; 553 } 554 555 void 556 sysctl_unregister_oid(struct sysctl_oid *oidp) 557 { 558 struct sysctl_oid *p; 559 int error; 560 561 SYSCTL_ASSERT_WLOCKED(); 562 if (oidp->oid_number == OID_AUTO) { 563 error = EINVAL; 564 } else { 565 error = ENOENT; 566 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 567 if (p == oidp) { 568 SLIST_REMOVE(oidp->oid_parent, oidp, 569 sysctl_oid, oid_link); 570 error = 0; 571 break; 572 } 573 } 574 } 575 576 /* 577 * This can happen when a module fails to register and is 578 * being unloaded afterwards. It should not be a panic() 579 * for normal use. 580 */ 581 if (error) { 582 printf("%s: failed(%d) to unregister sysctl(%s)\n", 583 __func__, error, oidp->oid_name); 584 } 585 } 586 587 /* Initialize a new context to keep track of dynamically added sysctls. */ 588 int 589 sysctl_ctx_init(struct sysctl_ctx_list *c) 590 { 591 592 if (c == NULL) { 593 return (EINVAL); 594 } 595 596 /* 597 * No locking here, the caller is responsible for not adding 598 * new nodes to a context until after this function has 599 * returned. 600 */ 601 TAILQ_INIT(c); 602 return (0); 603 } 604 605 /* Free the context, and destroy all dynamic oids registered in this context */ 606 int 607 sysctl_ctx_free(struct sysctl_ctx_list *clist) 608 { 609 struct sysctl_ctx_entry *e, *e1; 610 int error; 611 612 error = 0; 613 /* 614 * First perform a "dry run" to check if it's ok to remove oids. 615 * XXX FIXME 616 * XXX This algorithm is a hack. But I don't know any 617 * XXX better solution for now... 618 */ 619 SYSCTL_WLOCK(); 620 TAILQ_FOREACH(e, clist, link) { 621 error = sysctl_remove_oid_locked(e->entry, 0, 0); 622 if (error) 623 break; 624 } 625 /* 626 * Restore deregistered entries, either from the end, 627 * or from the place where error occurred. 628 * e contains the entry that was not unregistered 629 */ 630 if (error) 631 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 632 else 633 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 634 while (e1 != NULL) { 635 sysctl_register_oid(e1->entry); 636 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 637 } 638 if (error) { 639 SYSCTL_WUNLOCK(); 640 return(EBUSY); 641 } 642 /* Now really delete the entries */ 643 e = TAILQ_FIRST(clist); 644 while (e != NULL) { 645 e1 = TAILQ_NEXT(e, link); 646 error = sysctl_remove_oid_locked(e->entry, 1, 0); 647 if (error) 648 panic("sysctl_remove_oid: corrupt tree, entry: %s", 649 e->entry->oid_name); 650 free(e, M_SYSCTLOID); 651 e = e1; 652 } 653 SYSCTL_WUNLOCK(); 654 return (error); 655 } 656 657 /* Add an entry to the context */ 658 struct sysctl_ctx_entry * 659 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 660 { 661 struct sysctl_ctx_entry *e; 662 663 SYSCTL_ASSERT_WLOCKED(); 664 if (clist == NULL || oidp == NULL) 665 return(NULL); 666 e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 667 e->entry = oidp; 668 TAILQ_INSERT_HEAD(clist, e, link); 669 return (e); 670 } 671 672 /* Find an entry in the context */ 673 struct sysctl_ctx_entry * 674 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 675 { 676 struct sysctl_ctx_entry *e; 677 678 SYSCTL_ASSERT_WLOCKED(); 679 if (clist == NULL || oidp == NULL) 680 return(NULL); 681 TAILQ_FOREACH(e, clist, link) { 682 if(e->entry == oidp) 683 return(e); 684 } 685 return (e); 686 } 687 688 /* 689 * Delete an entry from the context. 690 * NOTE: this function doesn't free oidp! You have to remove it 691 * with sysctl_remove_oid(). 692 */ 693 int 694 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 695 { 696 struct sysctl_ctx_entry *e; 697 698 if (clist == NULL || oidp == NULL) 699 return (EINVAL); 700 SYSCTL_WLOCK(); 701 e = sysctl_ctx_entry_find(clist, oidp); 702 if (e != NULL) { 703 TAILQ_REMOVE(clist, e, link); 704 SYSCTL_WUNLOCK(); 705 free(e, M_SYSCTLOID); 706 return (0); 707 } else { 708 SYSCTL_WUNLOCK(); 709 return (ENOENT); 710 } 711 } 712 713 /* 714 * Remove dynamically created sysctl trees. 715 * oidp - top of the tree to be removed 716 * del - if 0 - just deregister, otherwise free up entries as well 717 * recurse - if != 0 traverse the subtree to be deleted 718 */ 719 int 720 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 721 { 722 int error; 723 724 SYSCTL_WLOCK(); 725 error = sysctl_remove_oid_locked(oidp, del, recurse); 726 SYSCTL_WUNLOCK(); 727 return (error); 728 } 729 730 int 731 sysctl_remove_name(struct sysctl_oid *parent, const char *name, 732 int del, int recurse) 733 { 734 struct sysctl_oid *p, *tmp; 735 int error; 736 737 error = ENOENT; 738 SYSCTL_WLOCK(); 739 SLIST_FOREACH_SAFE(p, SYSCTL_CHILDREN(parent), oid_link, tmp) { 740 if (strcmp(p->oid_name, name) == 0) { 741 error = sysctl_remove_oid_locked(p, del, recurse); 742 break; 743 } 744 } 745 SYSCTL_WUNLOCK(); 746 747 return (error); 748 } 749 750 static int 751 sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse) 752 { 753 struct sysctl_oid *p, *tmp; 754 int error; 755 756 SYSCTL_ASSERT_WLOCKED(); 757 if (oidp == NULL) 758 return(EINVAL); 759 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 760 printf("Warning: can't remove non-dynamic nodes (%s)!\n", 761 oidp->oid_name); 762 return (EINVAL); 763 } 764 /* 765 * WARNING: normal method to do this should be through 766 * sysctl_ctx_free(). Use recursing as the last resort 767 * method to purge your sysctl tree of leftovers... 768 * However, if some other code still references these nodes, 769 * it will panic. 770 */ 771 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 772 if (oidp->oid_refcnt == 1) { 773 SLIST_FOREACH_SAFE(p, 774 SYSCTL_CHILDREN(oidp), oid_link, tmp) { 775 if (!recurse) { 776 printf("Warning: failed attempt to " 777 "remove oid %s with child %s\n", 778 oidp->oid_name, p->oid_name); 779 return (ENOTEMPTY); 780 } 781 error = sysctl_remove_oid_locked(p, del, 782 recurse); 783 if (error) 784 return (error); 785 } 786 } 787 } 788 if (oidp->oid_refcnt > 1 ) { 789 oidp->oid_refcnt--; 790 } else { 791 if (oidp->oid_refcnt == 0) { 792 printf("Warning: bad oid_refcnt=%u (%s)!\n", 793 oidp->oid_refcnt, oidp->oid_name); 794 return (EINVAL); 795 } 796 sysctl_unregister_oid(oidp); 797 if (del) { 798 /* 799 * Wait for all threads running the handler to drain. 800 * This preserves the previous behavior when the 801 * sysctl lock was held across a handler invocation, 802 * and is necessary for module unload correctness. 803 */ 804 while (oidp->oid_running > 0) { 805 oidp->oid_kind |= CTLFLAG_DYING; 806 SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0); 807 } 808 if (oidp->oid_descr) 809 free(__DECONST(char *, oidp->oid_descr), 810 M_SYSCTLOID); 811 if (oidp->oid_label) 812 free(__DECONST(char *, oidp->oid_label), 813 M_SYSCTLOID); 814 free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); 815 free(oidp, M_SYSCTLOID); 816 } 817 } 818 return (0); 819 } 820 /* 821 * Create new sysctls at run time. 822 * clist may point to a valid context initialized with sysctl_ctx_init(). 823 */ 824 struct sysctl_oid * 825 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 826 int number, const char *name, int kind, void *arg1, intmax_t arg2, 827 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr, 828 const char *label) 829 { 830 struct sysctl_oid *oidp; 831 832 /* You have to hook up somewhere.. */ 833 if (parent == NULL) 834 return(NULL); 835 /* Check if the node already exists, otherwise create it */ 836 SYSCTL_WLOCK(); 837 oidp = sysctl_find_oidname(name, parent); 838 if (oidp != NULL) { 839 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 840 oidp->oid_refcnt++; 841 /* Update the context */ 842 if (clist != NULL) 843 sysctl_ctx_entry_add(clist, oidp); 844 SYSCTL_WUNLOCK(); 845 return (oidp); 846 } else { 847 sysctl_warn_reuse(__func__, oidp); 848 SYSCTL_WUNLOCK(); 849 return (NULL); 850 } 851 } 852 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO); 853 oidp->oid_parent = parent; 854 SLIST_INIT(&oidp->oid_children); 855 oidp->oid_number = number; 856 oidp->oid_refcnt = 1; 857 oidp->oid_name = strdup(name, M_SYSCTLOID); 858 oidp->oid_handler = handler; 859 oidp->oid_kind = CTLFLAG_DYN | kind; 860 oidp->oid_arg1 = arg1; 861 oidp->oid_arg2 = arg2; 862 oidp->oid_fmt = fmt; 863 if (descr != NULL) 864 oidp->oid_descr = strdup(descr, M_SYSCTLOID); 865 if (label != NULL) 866 oidp->oid_label = strdup(label, M_SYSCTLOID); 867 /* Update the context, if used */ 868 if (clist != NULL) 869 sysctl_ctx_entry_add(clist, oidp); 870 /* Register this oid */ 871 sysctl_register_oid(oidp); 872 SYSCTL_WUNLOCK(); 873 return (oidp); 874 } 875 876 /* 877 * Rename an existing oid. 878 */ 879 void 880 sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) 881 { 882 char *newname; 883 char *oldname; 884 885 newname = strdup(name, M_SYSCTLOID); 886 SYSCTL_WLOCK(); 887 oldname = __DECONST(char *, oidp->oid_name); 888 oidp->oid_name = newname; 889 SYSCTL_WUNLOCK(); 890 free(oldname, M_SYSCTLOID); 891 } 892 893 /* 894 * Reparent an existing oid. 895 */ 896 int 897 sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent) 898 { 899 struct sysctl_oid *oidp; 900 901 SYSCTL_WLOCK(); 902 if (oid->oid_parent == parent) { 903 SYSCTL_WUNLOCK(); 904 return (0); 905 } 906 oidp = sysctl_find_oidname(oid->oid_name, parent); 907 if (oidp != NULL) { 908 SYSCTL_WUNLOCK(); 909 return (EEXIST); 910 } 911 sysctl_unregister_oid(oid); 912 oid->oid_parent = parent; 913 oid->oid_number = OID_AUTO; 914 sysctl_register_oid(oid); 915 SYSCTL_WUNLOCK(); 916 return (0); 917 } 918 919 /* 920 * Register the kernel's oids on startup. 921 */ 922 SET_DECLARE(sysctl_set, struct sysctl_oid); 923 924 static void 925 sysctl_register_all(void *arg) 926 { 927 struct sysctl_oid **oidp; 928 929 sx_init(&sysctlmemlock, "sysctl mem"); 930 sx_init(&sysctlstringlock, "sysctl string handler"); 931 SYSCTL_INIT(); 932 SYSCTL_WLOCK(); 933 SET_FOREACH(oidp, sysctl_set) 934 sysctl_register_oid(*oidp); 935 SYSCTL_WUNLOCK(); 936 } 937 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, NULL); 938 939 /* 940 * "Staff-functions" 941 * 942 * These functions implement a presently undocumented interface 943 * used by the sysctl program to walk the tree, and get the type 944 * so it can print the value. 945 * This interface is under work and consideration, and should probably 946 * be killed with a big axe by the first person who can find the time. 947 * (be aware though, that the proper interface isn't as obvious as it 948 * may seem, there are various conflicting requirements. 949 * 950 * {CTL_SYSCTL, CTL_SYSCTL_DEBUG} printf the entire MIB-tree. 951 * {CTL_SYSCTL, CTL_SYSCTL_NAME, ...} return the name of the "..." 952 * OID. 953 * {CTL_SYSCTL, CTL_SYSCTL_NEXT, ...} return the next OID, honoring 954 * CTLFLAG_SKIP. 955 * {CTL_SYSCTL, CTL_SYSCTL_NAME2OID} return the OID of the name in 956 * "new" 957 * {CTL_SYSCTL, CTL_SYSCTL_OIDFMT, ...} return the kind & format info 958 * for the "..." OID. 959 * {CTL_SYSCTL, CTL_SYSCTL_OIDDESCR, ...} return the description of the 960 * "..." OID. 961 * {CTL_SYSCTL, CTL_SYSCTL_OIDLABEL, ...} return the aggregation label of 962 * the "..." OID. 963 * {CTL_SYSCTL, CTL_SYSCTL_NEXTNOSKIP, ...} return the next OID, ignoring 964 * CTLFLAG_SKIP. 965 */ 966 967 #ifdef SYSCTL_DEBUG 968 static void 969 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 970 { 971 int k; 972 struct sysctl_oid *oidp; 973 974 SYSCTL_ASSERT_LOCKED(); 975 SLIST_FOREACH(oidp, l, oid_link) { 976 for (k=0; k<i; k++) 977 printf(" "); 978 979 printf("%d %s ", oidp->oid_number, oidp->oid_name); 980 981 printf("%c%c", 982 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 983 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 984 985 if (oidp->oid_handler) 986 printf(" *Handler"); 987 988 switch (oidp->oid_kind & CTLTYPE) { 989 case CTLTYPE_NODE: 990 printf(" Node\n"); 991 if (!oidp->oid_handler) { 992 sysctl_sysctl_debug_dump_node( 993 SYSCTL_CHILDREN(oidp), i + 2); 994 } 995 break; 996 case CTLTYPE_INT: printf(" Int\n"); break; 997 case CTLTYPE_UINT: printf(" u_int\n"); break; 998 case CTLTYPE_LONG: printf(" Long\n"); break; 999 case CTLTYPE_ULONG: printf(" u_long\n"); break; 1000 case CTLTYPE_STRING: printf(" String\n"); break; 1001 case CTLTYPE_S8: printf(" int8_t\n"); break; 1002 case CTLTYPE_S16: printf(" int16_t\n"); break; 1003 case CTLTYPE_S32: printf(" int32_t\n"); break; 1004 case CTLTYPE_S64: printf(" int64_t\n"); break; 1005 case CTLTYPE_U8: printf(" uint8_t\n"); break; 1006 case CTLTYPE_U16: printf(" uint16_t\n"); break; 1007 case CTLTYPE_U32: printf(" uint32_t\n"); break; 1008 case CTLTYPE_U64: printf(" uint64_t\n"); break; 1009 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; 1010 default: printf("\n"); 1011 } 1012 } 1013 } 1014 1015 static int 1016 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 1017 { 1018 struct rm_priotracker tracker; 1019 int error; 1020 1021 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 1022 if (error) 1023 return (error); 1024 SYSCTL_RLOCK(&tracker); 1025 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 1026 SYSCTL_RUNLOCK(&tracker); 1027 return (ENOENT); 1028 } 1029 1030 SYSCTL_PROC(_sysctl, CTL_SYSCTL_DEBUG, debug, CTLTYPE_STRING | CTLFLAG_RD | 1031 CTLFLAG_MPSAFE, 0, 0, sysctl_sysctl_debug, "-", ""); 1032 #endif 1033 1034 static int 1035 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 1036 { 1037 int *name = (int *) arg1; 1038 u_int namelen = arg2; 1039 int error; 1040 struct sysctl_oid *oid; 1041 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 1042 struct rm_priotracker tracker; 1043 char buf[10]; 1044 1045 error = sysctl_wire_old_buffer(req, 0); 1046 if (error) 1047 return (error); 1048 1049 SYSCTL_RLOCK(&tracker); 1050 while (namelen) { 1051 if (!lsp) { 1052 snprintf(buf,sizeof(buf),"%d",*name); 1053 if (req->oldidx) 1054 error = SYSCTL_OUT(req, ".", 1); 1055 if (!error) 1056 error = SYSCTL_OUT(req, buf, strlen(buf)); 1057 if (error) 1058 goto out; 1059 namelen--; 1060 name++; 1061 continue; 1062 } 1063 lsp2 = NULL; 1064 SLIST_FOREACH(oid, lsp, oid_link) { 1065 if (oid->oid_number != *name) 1066 continue; 1067 1068 if (req->oldidx) 1069 error = SYSCTL_OUT(req, ".", 1); 1070 if (!error) 1071 error = SYSCTL_OUT(req, oid->oid_name, 1072 strlen(oid->oid_name)); 1073 if (error) 1074 goto out; 1075 1076 namelen--; 1077 name++; 1078 1079 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1080 break; 1081 1082 if (oid->oid_handler) 1083 break; 1084 1085 lsp2 = SYSCTL_CHILDREN(oid); 1086 break; 1087 } 1088 lsp = lsp2; 1089 } 1090 error = SYSCTL_OUT(req, "", 1); 1091 out: 1092 SYSCTL_RUNLOCK(&tracker); 1093 return (error); 1094 } 1095 1096 /* 1097 * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in 1098 * capability mode. 1099 */ 1100 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NAME, name, CTLFLAG_RD | 1101 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_name, ""); 1102 1103 static int 1104 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 1105 int *next, int *len, int level, struct sysctl_oid **oidpp, bool honor_skip) 1106 { 1107 struct sysctl_oid *oidp; 1108 1109 SYSCTL_ASSERT_LOCKED(); 1110 *len = level; 1111 SLIST_FOREACH(oidp, lsp, oid_link) { 1112 *next = oidp->oid_number; 1113 *oidpp = oidp; 1114 1115 if ((oidp->oid_kind & CTLFLAG_DORMANT) != 0) 1116 continue; 1117 1118 if (honor_skip && (oidp->oid_kind & CTLFLAG_SKIP) != 0) 1119 continue; 1120 1121 if (!namelen) { 1122 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1123 return (0); 1124 if (oidp->oid_handler) 1125 /* We really should call the handler here...*/ 1126 return (0); 1127 lsp = SYSCTL_CHILDREN(oidp); 1128 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 1129 len, level+1, oidpp, honor_skip)) 1130 return (0); 1131 goto emptynode; 1132 } 1133 1134 if (oidp->oid_number < *name) 1135 continue; 1136 1137 if (oidp->oid_number > *name) { 1138 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1139 return (0); 1140 if (oidp->oid_handler) 1141 return (0); 1142 lsp = SYSCTL_CHILDREN(oidp); 1143 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 1144 next+1, len, level+1, oidpp, honor_skip)) 1145 return (0); 1146 goto next; 1147 } 1148 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1149 continue; 1150 1151 if (oidp->oid_handler) 1152 continue; 1153 1154 lsp = SYSCTL_CHILDREN(oidp); 1155 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 1156 len, level+1, oidpp, honor_skip)) 1157 return (0); 1158 next: 1159 namelen = 1; 1160 emptynode: 1161 *len = level; 1162 } 1163 return (ENOENT); 1164 } 1165 1166 static int 1167 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 1168 { 1169 int *name = (int *) arg1; 1170 u_int namelen = arg2; 1171 int len, error; 1172 struct sysctl_oid *oid; 1173 struct sysctl_oid_list *lsp = &sysctl__children; 1174 struct rm_priotracker tracker; 1175 int next[CTL_MAXNAME]; 1176 1177 SYSCTL_RLOCK(&tracker); 1178 error = sysctl_sysctl_next_ls(lsp, name, namelen, next, &len, 1, &oid, 1179 oidp->oid_number == CTL_SYSCTL_NEXT); 1180 SYSCTL_RUNLOCK(&tracker); 1181 if (error) 1182 return (error); 1183 error = SYSCTL_OUT(req, next, len * sizeof (int)); 1184 return (error); 1185 } 1186 1187 /* 1188 * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in 1189 * capability mode. 1190 */ 1191 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXT, next, CTLFLAG_RD | 1192 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, ""); 1193 1194 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXTNOSKIP, nextnoskip, CTLFLAG_RD | 1195 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, ""); 1196 1197 static int 1198 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) 1199 { 1200 struct sysctl_oid *oidp; 1201 struct sysctl_oid_list *lsp = &sysctl__children; 1202 char *p; 1203 1204 SYSCTL_ASSERT_LOCKED(); 1205 1206 for (*len = 0; *len < CTL_MAXNAME;) { 1207 p = strsep(&name, "."); 1208 1209 oidp = SLIST_FIRST(lsp); 1210 for (;; oidp = SLIST_NEXT(oidp, oid_link)) { 1211 if (oidp == NULL) 1212 return (ENOENT); 1213 if (strcmp(p, oidp->oid_name) == 0) 1214 break; 1215 } 1216 *oid++ = oidp->oid_number; 1217 (*len)++; 1218 1219 if (name == NULL || *name == '\0') { 1220 if (oidpp) 1221 *oidpp = oidp; 1222 return (0); 1223 } 1224 1225 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1226 break; 1227 1228 if (oidp->oid_handler) 1229 break; 1230 1231 lsp = SYSCTL_CHILDREN(oidp); 1232 } 1233 return (ENOENT); 1234 } 1235 1236 static int 1237 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 1238 { 1239 char *p; 1240 int error, oid[CTL_MAXNAME], len = 0; 1241 struct sysctl_oid *op = NULL; 1242 struct rm_priotracker tracker; 1243 char buf[32]; 1244 1245 if (!req->newlen) 1246 return (ENOENT); 1247 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 1248 return (ENAMETOOLONG); 1249 1250 p = buf; 1251 if (req->newlen >= sizeof(buf)) 1252 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); 1253 1254 error = SYSCTL_IN(req, p, req->newlen); 1255 if (error) { 1256 if (p != buf) 1257 free(p, M_SYSCTL); 1258 return (error); 1259 } 1260 1261 p [req->newlen] = '\0'; 1262 1263 SYSCTL_RLOCK(&tracker); 1264 error = name2oid(p, oid, &len, &op); 1265 SYSCTL_RUNLOCK(&tracker); 1266 1267 if (p != buf) 1268 free(p, M_SYSCTL); 1269 1270 if (error) 1271 return (error); 1272 1273 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 1274 return (error); 1275 } 1276 1277 /* 1278 * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in 1279 * capability mode. 1280 */ 1281 SYSCTL_PROC(_sysctl, CTL_SYSCTL_NAME2OID, name2oid, CTLTYPE_INT | CTLFLAG_RW | 1282 CTLFLAG_ANYBODY | CTLFLAG_MPSAFE | CTLFLAG_CAPRW, 0, 0, 1283 sysctl_sysctl_name2oid, "I", ""); 1284 1285 static int 1286 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 1287 { 1288 struct sysctl_oid *oid; 1289 struct rm_priotracker tracker; 1290 int error; 1291 1292 error = sysctl_wire_old_buffer(req, 0); 1293 if (error) 1294 return (error); 1295 1296 SYSCTL_RLOCK(&tracker); 1297 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1298 if (error) 1299 goto out; 1300 1301 if (oid->oid_fmt == NULL) { 1302 error = ENOENT; 1303 goto out; 1304 } 1305 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 1306 if (error) 1307 goto out; 1308 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 1309 out: 1310 SYSCTL_RUNLOCK(&tracker); 1311 return (error); 1312 } 1313 1314 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDFMT, oidfmt, CTLFLAG_RD | 1315 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidfmt, ""); 1316 1317 static int 1318 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 1319 { 1320 struct sysctl_oid *oid; 1321 struct rm_priotracker tracker; 1322 int error; 1323 1324 error = sysctl_wire_old_buffer(req, 0); 1325 if (error) 1326 return (error); 1327 1328 SYSCTL_RLOCK(&tracker); 1329 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1330 if (error) 1331 goto out; 1332 1333 if (oid->oid_descr == NULL) { 1334 error = ENOENT; 1335 goto out; 1336 } 1337 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 1338 out: 1339 SYSCTL_RUNLOCK(&tracker); 1340 return (error); 1341 } 1342 1343 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDDESCR, oiddescr, CTLFLAG_RD | 1344 CTLFLAG_MPSAFE|CTLFLAG_CAPRD, sysctl_sysctl_oiddescr, ""); 1345 1346 static int 1347 sysctl_sysctl_oidlabel(SYSCTL_HANDLER_ARGS) 1348 { 1349 struct sysctl_oid *oid; 1350 struct rm_priotracker tracker; 1351 int error; 1352 1353 error = sysctl_wire_old_buffer(req, 0); 1354 if (error) 1355 return (error); 1356 1357 SYSCTL_RLOCK(&tracker); 1358 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1359 if (error) 1360 goto out; 1361 1362 if (oid->oid_label == NULL) { 1363 error = ENOENT; 1364 goto out; 1365 } 1366 error = SYSCTL_OUT(req, oid->oid_label, strlen(oid->oid_label) + 1); 1367 out: 1368 SYSCTL_RUNLOCK(&tracker); 1369 return (error); 1370 } 1371 1372 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDLABEL, oidlabel, CTLFLAG_RD | 1373 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidlabel, ""); 1374 1375 /* 1376 * Default "handler" functions. 1377 */ 1378 1379 /* 1380 * Handle a bool. 1381 * Two cases: 1382 * a variable: point arg1 at it. 1383 * a constant: pass it in arg2. 1384 */ 1385 1386 int 1387 sysctl_handle_bool(SYSCTL_HANDLER_ARGS) 1388 { 1389 uint8_t temp; 1390 int error; 1391 1392 /* 1393 * Attempt to get a coherent snapshot by making a copy of the data. 1394 */ 1395 if (arg1) 1396 temp = *(bool *)arg1 ? 1 : 0; 1397 else 1398 temp = arg2 ? 1 : 0; 1399 1400 error = SYSCTL_OUT(req, &temp, sizeof(temp)); 1401 if (error || !req->newptr) 1402 return (error); 1403 1404 if (!arg1) 1405 error = EPERM; 1406 else { 1407 error = SYSCTL_IN(req, &temp, sizeof(temp)); 1408 if (!error) 1409 *(bool *)arg1 = temp ? 1 : 0; 1410 } 1411 return (error); 1412 } 1413 1414 /* 1415 * Handle an int8_t, signed or unsigned. 1416 * Two cases: 1417 * a variable: point arg1 at it. 1418 * a constant: pass it in arg2. 1419 */ 1420 1421 int 1422 sysctl_handle_8(SYSCTL_HANDLER_ARGS) 1423 { 1424 int8_t tmpout; 1425 int error = 0; 1426 1427 /* 1428 * Attempt to get a coherent snapshot by making a copy of the data. 1429 */ 1430 if (arg1) 1431 tmpout = *(int8_t *)arg1; 1432 else 1433 tmpout = arg2; 1434 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1435 1436 if (error || !req->newptr) 1437 return (error); 1438 1439 if (!arg1) 1440 error = EPERM; 1441 else 1442 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1443 return (error); 1444 } 1445 1446 /* 1447 * Handle an int16_t, signed or unsigned. 1448 * Two cases: 1449 * a variable: point arg1 at it. 1450 * a constant: pass it in arg2. 1451 */ 1452 1453 int 1454 sysctl_handle_16(SYSCTL_HANDLER_ARGS) 1455 { 1456 int16_t tmpout; 1457 int error = 0; 1458 1459 /* 1460 * Attempt to get a coherent snapshot by making a copy of the data. 1461 */ 1462 if (arg1) 1463 tmpout = *(int16_t *)arg1; 1464 else 1465 tmpout = arg2; 1466 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1467 1468 if (error || !req->newptr) 1469 return (error); 1470 1471 if (!arg1) 1472 error = EPERM; 1473 else 1474 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1475 return (error); 1476 } 1477 1478 /* 1479 * Handle an int32_t, signed or unsigned. 1480 * Two cases: 1481 * a variable: point arg1 at it. 1482 * a constant: pass it in arg2. 1483 */ 1484 1485 int 1486 sysctl_handle_32(SYSCTL_HANDLER_ARGS) 1487 { 1488 int32_t tmpout; 1489 int error = 0; 1490 1491 /* 1492 * Attempt to get a coherent snapshot by making a copy of the data. 1493 */ 1494 if (arg1) 1495 tmpout = *(int32_t *)arg1; 1496 else 1497 tmpout = arg2; 1498 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1499 1500 if (error || !req->newptr) 1501 return (error); 1502 1503 if (!arg1) 1504 error = EPERM; 1505 else 1506 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1507 return (error); 1508 } 1509 1510 /* 1511 * Handle an int, signed or unsigned. 1512 * Two cases: 1513 * a variable: point arg1 at it. 1514 * a constant: pass it in arg2. 1515 */ 1516 1517 int 1518 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 1519 { 1520 int tmpout, error = 0; 1521 1522 /* 1523 * Attempt to get a coherent snapshot by making a copy of the data. 1524 */ 1525 if (arg1) 1526 tmpout = *(int *)arg1; 1527 else 1528 tmpout = arg2; 1529 error = SYSCTL_OUT(req, &tmpout, sizeof(int)); 1530 1531 if (error || !req->newptr) 1532 return (error); 1533 1534 if (!arg1) 1535 error = EPERM; 1536 else 1537 error = SYSCTL_IN(req, arg1, sizeof(int)); 1538 return (error); 1539 } 1540 1541 /* 1542 * Based on on sysctl_handle_int() convert milliseconds into ticks. 1543 * Note: this is used by TCP. 1544 */ 1545 1546 int 1547 sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) 1548 { 1549 int error, s, tt; 1550 1551 tt = *(int *)arg1; 1552 s = (int)((int64_t)tt * 1000 / hz); 1553 1554 error = sysctl_handle_int(oidp, &s, 0, req); 1555 if (error || !req->newptr) 1556 return (error); 1557 1558 tt = (int)((int64_t)s * hz / 1000); 1559 if (tt < 1) 1560 return (EINVAL); 1561 1562 *(int *)arg1 = tt; 1563 return (0); 1564 } 1565 1566 /* 1567 * Handle a long, signed or unsigned. 1568 * Two cases: 1569 * a variable: point arg1 at it. 1570 * a constant: pass it in arg2. 1571 */ 1572 1573 int 1574 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 1575 { 1576 int error = 0; 1577 long tmplong; 1578 #ifdef SCTL_MASK32 1579 int tmpint; 1580 #endif 1581 1582 /* 1583 * Attempt to get a coherent snapshot by making a copy of the data. 1584 */ 1585 if (arg1) 1586 tmplong = *(long *)arg1; 1587 else 1588 tmplong = arg2; 1589 #ifdef SCTL_MASK32 1590 if (req->flags & SCTL_MASK32) { 1591 tmpint = tmplong; 1592 error = SYSCTL_OUT(req, &tmpint, sizeof(int)); 1593 } else 1594 #endif 1595 error = SYSCTL_OUT(req, &tmplong, sizeof(long)); 1596 1597 if (error || !req->newptr) 1598 return (error); 1599 1600 if (!arg1) 1601 error = EPERM; 1602 #ifdef SCTL_MASK32 1603 else if (req->flags & SCTL_MASK32) { 1604 error = SYSCTL_IN(req, &tmpint, sizeof(int)); 1605 *(long *)arg1 = (long)tmpint; 1606 } 1607 #endif 1608 else 1609 error = SYSCTL_IN(req, arg1, sizeof(long)); 1610 return (error); 1611 } 1612 1613 /* 1614 * Handle a 64 bit int, signed or unsigned. 1615 * Two cases: 1616 * a variable: point arg1 at it. 1617 * a constant: pass it in arg2. 1618 */ 1619 int 1620 sysctl_handle_64(SYSCTL_HANDLER_ARGS) 1621 { 1622 int error = 0; 1623 uint64_t tmpout; 1624 1625 /* 1626 * Attempt to get a coherent snapshot by making a copy of the data. 1627 */ 1628 if (arg1) 1629 tmpout = *(uint64_t *)arg1; 1630 else 1631 tmpout = arg2; 1632 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t)); 1633 1634 if (error || !req->newptr) 1635 return (error); 1636 1637 if (!arg1) 1638 error = EPERM; 1639 else 1640 error = SYSCTL_IN(req, arg1, sizeof(uint64_t)); 1641 return (error); 1642 } 1643 1644 /* 1645 * Handle our generic '\0' terminated 'C' string. 1646 * Two cases: 1647 * a variable string: point arg1 at it, arg2 is max length. 1648 * a constant string: point arg1 at it, arg2 is zero. 1649 */ 1650 1651 int 1652 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 1653 { 1654 char *tmparg; 1655 size_t outlen; 1656 int error = 0, ro_string = 0; 1657 1658 /* 1659 * If the sysctl isn't writable and isn't a preallocated tunable that 1660 * can be modified by kenv(2), microoptimise and treat it as a 1661 * read-only string. 1662 * A zero-length buffer indicates a fixed size read-only 1663 * string. In ddb, don't worry about trying to make a malloced 1664 * snapshot. 1665 */ 1666 if ((oidp->oid_kind & (CTLFLAG_WR | CTLFLAG_TUN)) == 0 || 1667 arg2 == 0 || kdb_active) { 1668 arg2 = strlen((char *)arg1) + 1; 1669 ro_string = 1; 1670 } 1671 1672 if (req->oldptr != NULL) { 1673 if (ro_string) { 1674 tmparg = arg1; 1675 outlen = strlen(tmparg) + 1; 1676 } else { 1677 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1678 sx_slock(&sysctlstringlock); 1679 memcpy(tmparg, arg1, arg2); 1680 sx_sunlock(&sysctlstringlock); 1681 outlen = strlen(tmparg) + 1; 1682 } 1683 1684 error = SYSCTL_OUT(req, tmparg, outlen); 1685 1686 if (!ro_string) 1687 free(tmparg, M_SYSCTLTMP); 1688 } else { 1689 if (!ro_string) 1690 sx_slock(&sysctlstringlock); 1691 outlen = strlen((char *)arg1) + 1; 1692 if (!ro_string) 1693 sx_sunlock(&sysctlstringlock); 1694 error = SYSCTL_OUT(req, NULL, outlen); 1695 } 1696 if (error || !req->newptr) 1697 return (error); 1698 1699 if (req->newlen - req->newidx >= arg2 || 1700 req->newlen - req->newidx < 0) { 1701 error = EINVAL; 1702 } else if (req->newlen - req->newidx == 0) { 1703 sx_xlock(&sysctlstringlock); 1704 ((char *)arg1)[0] = '\0'; 1705 sx_xunlock(&sysctlstringlock); 1706 } else { 1707 arg2 = req->newlen - req->newidx; 1708 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1709 1710 error = SYSCTL_IN(req, tmparg, arg2); 1711 if (error) { 1712 free(tmparg, M_SYSCTLTMP); 1713 return (error); 1714 } 1715 1716 sx_xlock(&sysctlstringlock); 1717 memcpy(arg1, tmparg, arg2); 1718 ((char *)arg1)[arg2] = '\0'; 1719 sx_xunlock(&sysctlstringlock); 1720 free(tmparg, M_SYSCTLTMP); 1721 req->newidx += arg2; 1722 } 1723 return (error); 1724 } 1725 1726 /* 1727 * Handle any kind of opaque data. 1728 * arg1 points to it, arg2 is the size. 1729 */ 1730 1731 int 1732 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 1733 { 1734 int error, tries; 1735 u_int generation; 1736 struct sysctl_req req2; 1737 1738 /* 1739 * Attempt to get a coherent snapshot, by using the thread 1740 * pre-emption counter updated from within mi_switch() to 1741 * determine if we were pre-empted during a bcopy() or 1742 * copyout(). Make 3 attempts at doing this before giving up. 1743 * If we encounter an error, stop immediately. 1744 */ 1745 tries = 0; 1746 req2 = *req; 1747 retry: 1748 generation = curthread->td_generation; 1749 error = SYSCTL_OUT(req, arg1, arg2); 1750 if (error) 1751 return (error); 1752 tries++; 1753 if (generation != curthread->td_generation && tries < 3) { 1754 *req = req2; 1755 goto retry; 1756 } 1757 1758 error = SYSCTL_IN(req, arg1, arg2); 1759 1760 return (error); 1761 } 1762 1763 /* 1764 * Based on on sysctl_handle_int() convert microseconds to a sbintime. 1765 */ 1766 int 1767 sysctl_usec_to_sbintime(SYSCTL_HANDLER_ARGS) 1768 { 1769 int error; 1770 int64_t tt; 1771 sbintime_t sb; 1772 1773 tt = *(int64_t *)arg1; 1774 sb = sbttous(tt); 1775 1776 error = sysctl_handle_64(oidp, &sb, 0, req); 1777 if (error || !req->newptr) 1778 return (error); 1779 1780 tt = ustosbt(sb); 1781 *(int64_t *)arg1 = tt; 1782 1783 return (0); 1784 } 1785 1786 /* 1787 * Based on on sysctl_handle_int() convert milliseconds to a sbintime. 1788 */ 1789 int 1790 sysctl_msec_to_sbintime(SYSCTL_HANDLER_ARGS) 1791 { 1792 int error; 1793 int64_t tt; 1794 sbintime_t sb; 1795 1796 tt = *(int64_t *)arg1; 1797 sb = sbttoms(tt); 1798 1799 error = sysctl_handle_64(oidp, &sb, 0, req); 1800 if (error || !req->newptr) 1801 return (error); 1802 1803 tt = mstosbt(sb); 1804 *(int64_t *)arg1 = tt; 1805 1806 return (0); 1807 } 1808 1809 /* 1810 * Convert seconds to a struct timeval. Intended for use with 1811 * intervals and thus does not permit negative seconds. 1812 */ 1813 int 1814 sysctl_sec_to_timeval(SYSCTL_HANDLER_ARGS) 1815 { 1816 struct timeval *tv; 1817 int error, secs; 1818 1819 tv = arg1; 1820 secs = tv->tv_sec; 1821 1822 error = sysctl_handle_int(oidp, &secs, 0, req); 1823 if (error || req->newptr == NULL) 1824 return (error); 1825 1826 if (secs < 0) 1827 return (EINVAL); 1828 tv->tv_sec = secs; 1829 1830 return (0); 1831 } 1832 1833 /* 1834 * Transfer functions to/from kernel space. 1835 * XXX: rather untested at this point 1836 */ 1837 static int 1838 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 1839 { 1840 size_t i = 0; 1841 1842 if (req->oldptr) { 1843 i = l; 1844 if (req->oldlen <= req->oldidx) 1845 i = 0; 1846 else 1847 if (i > req->oldlen - req->oldidx) 1848 i = req->oldlen - req->oldidx; 1849 if (i > 0) 1850 bcopy(p, (char *)req->oldptr + req->oldidx, i); 1851 } 1852 req->oldidx += l; 1853 if (req->oldptr && i != l) 1854 return (ENOMEM); 1855 return (0); 1856 } 1857 1858 static int 1859 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 1860 { 1861 if (!req->newptr) 1862 return (0); 1863 if (req->newlen - req->newidx < l) 1864 return (EINVAL); 1865 bcopy((const char *)req->newptr + req->newidx, p, l); 1866 req->newidx += l; 1867 return (0); 1868 } 1869 1870 int 1871 kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1872 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) 1873 { 1874 int error = 0; 1875 struct sysctl_req req; 1876 1877 bzero(&req, sizeof req); 1878 1879 req.td = td; 1880 req.flags = flags; 1881 1882 if (oldlenp) { 1883 req.oldlen = *oldlenp; 1884 } 1885 req.validlen = req.oldlen; 1886 1887 if (old) { 1888 req.oldptr= old; 1889 } 1890 1891 if (new != NULL) { 1892 req.newlen = newlen; 1893 req.newptr = new; 1894 } 1895 1896 req.oldfunc = sysctl_old_kernel; 1897 req.newfunc = sysctl_new_kernel; 1898 req.lock = REQ_UNWIRED; 1899 1900 error = sysctl_root(0, name, namelen, &req); 1901 1902 if (req.lock == REQ_WIRED && req.validlen > 0) 1903 vsunlock(req.oldptr, req.validlen); 1904 1905 if (error && error != ENOMEM) 1906 return (error); 1907 1908 if (retval) { 1909 if (req.oldptr && req.oldidx > req.validlen) 1910 *retval = req.validlen; 1911 else 1912 *retval = req.oldidx; 1913 } 1914 return (error); 1915 } 1916 1917 int 1918 kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp, 1919 void *new, size_t newlen, size_t *retval, int flags) 1920 { 1921 int oid[CTL_MAXNAME]; 1922 size_t oidlen, plen; 1923 int error; 1924 1925 oid[0] = CTL_SYSCTL; 1926 oid[1] = CTL_SYSCTL_NAME2OID; 1927 oidlen = sizeof(oid); 1928 1929 error = kernel_sysctl(td, oid, 2, oid, &oidlen, 1930 (void *)name, strlen(name), &plen, flags); 1931 if (error) 1932 return (error); 1933 1934 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp, 1935 new, newlen, retval, flags); 1936 return (error); 1937 } 1938 1939 /* 1940 * Transfer function to/from user space. 1941 */ 1942 static int 1943 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1944 { 1945 size_t i, len, origidx; 1946 int error; 1947 1948 origidx = req->oldidx; 1949 req->oldidx += l; 1950 if (req->oldptr == NULL) 1951 return (0); 1952 /* 1953 * If we have not wired the user supplied buffer and we are currently 1954 * holding locks, drop a witness warning, as it's possible that 1955 * write operations to the user page can sleep. 1956 */ 1957 if (req->lock != REQ_WIRED) 1958 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1959 "sysctl_old_user()"); 1960 i = l; 1961 len = req->validlen; 1962 if (len <= origidx) 1963 i = 0; 1964 else { 1965 if (i > len - origidx) 1966 i = len - origidx; 1967 if (req->lock == REQ_WIRED) { 1968 error = copyout_nofault(p, (char *)req->oldptr + 1969 origidx, i); 1970 } else 1971 error = copyout(p, (char *)req->oldptr + origidx, i); 1972 if (error != 0) 1973 return (error); 1974 } 1975 if (i < l) 1976 return (ENOMEM); 1977 return (0); 1978 } 1979 1980 static int 1981 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1982 { 1983 int error; 1984 1985 if (!req->newptr) 1986 return (0); 1987 if (req->newlen - req->newidx < l) 1988 return (EINVAL); 1989 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1990 "sysctl_new_user()"); 1991 error = copyin((const char *)req->newptr + req->newidx, p, l); 1992 req->newidx += l; 1993 return (error); 1994 } 1995 1996 /* 1997 * Wire the user space destination buffer. If set to a value greater than 1998 * zero, the len parameter limits the maximum amount of wired memory. 1999 */ 2000 int 2001 sysctl_wire_old_buffer(struct sysctl_req *req, size_t len) 2002 { 2003 int ret; 2004 size_t wiredlen; 2005 2006 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen; 2007 ret = 0; 2008 if (req->lock != REQ_WIRED && req->oldptr && 2009 req->oldfunc == sysctl_old_user) { 2010 if (wiredlen != 0) { 2011 ret = vslock(req->oldptr, wiredlen); 2012 if (ret != 0) { 2013 if (ret != ENOMEM) 2014 return (ret); 2015 wiredlen = 0; 2016 } 2017 } 2018 req->lock = REQ_WIRED; 2019 req->validlen = wiredlen; 2020 } 2021 return (0); 2022 } 2023 2024 int 2025 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 2026 int *nindx, struct sysctl_req *req) 2027 { 2028 struct sysctl_oid_list *lsp; 2029 struct sysctl_oid *oid; 2030 int indx; 2031 2032 SYSCTL_ASSERT_LOCKED(); 2033 lsp = &sysctl__children; 2034 indx = 0; 2035 while (indx < CTL_MAXNAME) { 2036 SLIST_FOREACH(oid, lsp, oid_link) { 2037 if (oid->oid_number == name[indx]) 2038 break; 2039 } 2040 if (oid == NULL) 2041 return (ENOENT); 2042 2043 indx++; 2044 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2045 if (oid->oid_handler != NULL || indx == namelen) { 2046 *noid = oid; 2047 if (nindx != NULL) 2048 *nindx = indx; 2049 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 2050 ("%s found DYING node %p", __func__, oid)); 2051 return (0); 2052 } 2053 lsp = SYSCTL_CHILDREN(oid); 2054 } else if (indx == namelen) { 2055 if ((oid->oid_kind & CTLFLAG_DORMANT) != 0) 2056 return (ENOENT); 2057 *noid = oid; 2058 if (nindx != NULL) 2059 *nindx = indx; 2060 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 2061 ("%s found DYING node %p", __func__, oid)); 2062 return (0); 2063 } else { 2064 return (ENOTDIR); 2065 } 2066 } 2067 return (ENOENT); 2068 } 2069 2070 /* 2071 * Traverse our tree, and find the right node, execute whatever it points 2072 * to, and return the resulting error code. 2073 */ 2074 2075 static int 2076 sysctl_root(SYSCTL_HANDLER_ARGS) 2077 { 2078 struct sysctl_oid *oid; 2079 struct rm_priotracker tracker; 2080 int error, indx, lvl; 2081 2082 SYSCTL_RLOCK(&tracker); 2083 2084 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 2085 if (error) 2086 goto out; 2087 2088 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2089 /* 2090 * You can't call a sysctl when it's a node, but has 2091 * no handler. Inform the user that it's a node. 2092 * The indx may or may not be the same as namelen. 2093 */ 2094 if (oid->oid_handler == NULL) { 2095 error = EISDIR; 2096 goto out; 2097 } 2098 } 2099 2100 /* Is this sysctl writable? */ 2101 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) { 2102 error = EPERM; 2103 goto out; 2104 } 2105 2106 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL")); 2107 2108 #ifdef CAPABILITY_MODE 2109 /* 2110 * If the process is in capability mode, then don't permit reading or 2111 * writing unless specifically granted for the node. 2112 */ 2113 if (IN_CAPABILITY_MODE(req->td)) { 2114 if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) || 2115 (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) { 2116 error = EPERM; 2117 goto out; 2118 } 2119 } 2120 #endif 2121 2122 /* Is this sysctl sensitive to securelevels? */ 2123 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) { 2124 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE; 2125 error = securelevel_gt(req->td->td_ucred, lvl); 2126 if (error) 2127 goto out; 2128 } 2129 2130 /* Is this sysctl writable by only privileged users? */ 2131 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) { 2132 int priv; 2133 2134 if (oid->oid_kind & CTLFLAG_PRISON) 2135 priv = PRIV_SYSCTL_WRITEJAIL; 2136 #ifdef VIMAGE 2137 else if ((oid->oid_kind & CTLFLAG_VNET) && 2138 prison_owns_vnet(req->td->td_ucred)) 2139 priv = PRIV_SYSCTL_WRITEJAIL; 2140 #endif 2141 else 2142 priv = PRIV_SYSCTL_WRITE; 2143 error = priv_check(req->td, priv); 2144 if (error) 2145 goto out; 2146 } 2147 2148 if (!oid->oid_handler) { 2149 error = EINVAL; 2150 goto out; 2151 } 2152 2153 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2154 arg1 = (int *)arg1 + indx; 2155 arg2 -= indx; 2156 } else { 2157 arg1 = oid->oid_arg1; 2158 arg2 = oid->oid_arg2; 2159 } 2160 #ifdef MAC 2161 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2, 2162 req); 2163 if (error != 0) 2164 goto out; 2165 #endif 2166 #ifdef VIMAGE 2167 if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL) 2168 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1); 2169 #endif 2170 error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker); 2171 2172 out: 2173 SYSCTL_RUNLOCK(&tracker); 2174 return (error); 2175 } 2176 2177 #ifndef _SYS_SYSPROTO_H_ 2178 struct sysctl_args { 2179 int *name; 2180 u_int namelen; 2181 void *old; 2182 size_t *oldlenp; 2183 void *new; 2184 size_t newlen; 2185 }; 2186 #endif 2187 int 2188 sys___sysctl(struct thread *td, struct sysctl_args *uap) 2189 { 2190 int error, i, name[CTL_MAXNAME]; 2191 size_t j; 2192 2193 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 2194 return (EINVAL); 2195 2196 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 2197 if (error) 2198 return (error); 2199 2200 error = userland_sysctl(td, name, uap->namelen, 2201 uap->old, uap->oldlenp, 0, 2202 uap->new, uap->newlen, &j, 0); 2203 if (error && error != ENOMEM) 2204 return (error); 2205 if (uap->oldlenp) { 2206 i = copyout(&j, uap->oldlenp, sizeof(j)); 2207 if (i) 2208 return (i); 2209 } 2210 return (error); 2211 } 2212 2213 int 2214 kern___sysctlbyname(struct thread *td, const char *oname, size_t namelen, 2215 void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval, 2216 int flags, bool inkernel) 2217 { 2218 int oid[CTL_MAXNAME]; 2219 char namebuf[16]; 2220 char *name; 2221 size_t oidlen; 2222 int error; 2223 2224 if (namelen > MAXPATHLEN || namelen == 0) 2225 return (EINVAL); 2226 name = namebuf; 2227 if (namelen > sizeof(namebuf)) 2228 name = malloc(namelen, M_SYSCTL, M_WAITOK); 2229 error = copyin(oname, name, namelen); 2230 if (error != 0) 2231 goto out; 2232 2233 oid[0] = CTL_SYSCTL; 2234 oid[1] = CTL_SYSCTL_NAME2OID; 2235 oidlen = sizeof(oid); 2236 error = kernel_sysctl(td, oid, 2, oid, &oidlen, (void *)name, namelen, 2237 retval, flags); 2238 if (error != 0) 2239 goto out; 2240 error = userland_sysctl(td, oid, *retval / sizeof(int), old, oldlenp, 2241 inkernel, new, newlen, retval, flags); 2242 2243 out: 2244 if (namelen > sizeof(namebuf)) 2245 free(name, M_SYSCTL); 2246 return (error); 2247 } 2248 2249 #ifndef _SYS_SYSPROTO_H_ 2250 struct __sysctlbyname_args { 2251 const char *name; 2252 size_t namelen; 2253 void *old; 2254 size_t *oldlenp; 2255 void *new; 2256 size_t newlen; 2257 }; 2258 #endif 2259 int 2260 sys___sysctlbyname(struct thread *td, struct __sysctlbyname_args *uap) 2261 { 2262 size_t rv; 2263 int error; 2264 2265 error = kern___sysctlbyname(td, uap->name, uap->namelen, uap->old, 2266 uap->oldlenp, uap->new, uap->newlen, &rv, 0, 0); 2267 if (error != 0) 2268 return (error); 2269 if (uap->oldlenp != NULL) 2270 error = copyout(&rv, uap->oldlenp, sizeof(rv)); 2271 2272 return (error); 2273 } 2274 2275 /* 2276 * This is used from various compatibility syscalls too. That's why name 2277 * must be in kernel space. 2278 */ 2279 int 2280 userland_sysctl(struct thread *td, int *name, u_int namelen, void *old, 2281 size_t *oldlenp, int inkernel, const void *new, size_t newlen, 2282 size_t *retval, int flags) 2283 { 2284 int error = 0, memlocked; 2285 struct sysctl_req req; 2286 2287 bzero(&req, sizeof req); 2288 2289 req.td = td; 2290 req.flags = flags; 2291 2292 if (oldlenp) { 2293 if (inkernel) { 2294 req.oldlen = *oldlenp; 2295 } else { 2296 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 2297 if (error) 2298 return (error); 2299 } 2300 } 2301 req.validlen = req.oldlen; 2302 req.oldptr = old; 2303 2304 if (new != NULL) { 2305 req.newlen = newlen; 2306 req.newptr = new; 2307 } 2308 2309 req.oldfunc = sysctl_old_user; 2310 req.newfunc = sysctl_new_user; 2311 req.lock = REQ_UNWIRED; 2312 2313 #ifdef KTRACE 2314 if (KTRPOINT(curthread, KTR_SYSCTL)) 2315 ktrsysctl(name, namelen); 2316 #endif 2317 memlocked = 0; 2318 if (req.oldptr && req.oldlen > 4 * PAGE_SIZE) { 2319 memlocked = 1; 2320 sx_xlock(&sysctlmemlock); 2321 } 2322 CURVNET_SET(TD_TO_VNET(td)); 2323 2324 for (;;) { 2325 req.oldidx = 0; 2326 req.newidx = 0; 2327 error = sysctl_root(0, name, namelen, &req); 2328 if (error != EAGAIN) 2329 break; 2330 kern_yield(PRI_USER); 2331 } 2332 2333 CURVNET_RESTORE(); 2334 2335 if (req.lock == REQ_WIRED && req.validlen > 0) 2336 vsunlock(req.oldptr, req.validlen); 2337 if (memlocked) 2338 sx_xunlock(&sysctlmemlock); 2339 2340 if (error && error != ENOMEM) 2341 return (error); 2342 2343 if (retval) { 2344 if (req.oldptr && req.oldidx > req.validlen) 2345 *retval = req.validlen; 2346 else 2347 *retval = req.oldidx; 2348 } 2349 return (error); 2350 } 2351 2352 /* 2353 * Drain into a sysctl struct. The user buffer should be wired if a page 2354 * fault would cause issue. 2355 */ 2356 static int 2357 sbuf_sysctl_drain(void *arg, const char *data, int len) 2358 { 2359 struct sysctl_req *req = arg; 2360 int error; 2361 2362 error = SYSCTL_OUT(req, data, len); 2363 KASSERT(error >= 0, ("Got unexpected negative value %d", error)); 2364 return (error == 0 ? len : -error); 2365 } 2366 2367 struct sbuf * 2368 sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, 2369 struct sysctl_req *req) 2370 { 2371 2372 /* Supply a default buffer size if none given. */ 2373 if (buf == NULL && length == 0) 2374 length = 64; 2375 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL); 2376 sbuf_set_drain(s, sbuf_sysctl_drain, req); 2377 return (s); 2378 } 2379 2380 #ifdef DDB 2381 2382 /* The current OID the debugger is working with */ 2383 static struct sysctl_oid *g_ddb_oid; 2384 2385 /* The current flags specified by the user */ 2386 static int g_ddb_sysctl_flags; 2387 2388 /* Check to see if the last sysctl printed */ 2389 static int g_ddb_sysctl_printed; 2390 2391 static const int ctl_sign[CTLTYPE+1] = { 2392 [CTLTYPE_INT] = 1, 2393 [CTLTYPE_LONG] = 1, 2394 [CTLTYPE_S8] = 1, 2395 [CTLTYPE_S16] = 1, 2396 [CTLTYPE_S32] = 1, 2397 [CTLTYPE_S64] = 1, 2398 }; 2399 2400 static const int ctl_size[CTLTYPE+1] = { 2401 [CTLTYPE_INT] = sizeof(int), 2402 [CTLTYPE_UINT] = sizeof(u_int), 2403 [CTLTYPE_LONG] = sizeof(long), 2404 [CTLTYPE_ULONG] = sizeof(u_long), 2405 [CTLTYPE_S8] = sizeof(int8_t), 2406 [CTLTYPE_S16] = sizeof(int16_t), 2407 [CTLTYPE_S32] = sizeof(int32_t), 2408 [CTLTYPE_S64] = sizeof(int64_t), 2409 [CTLTYPE_U8] = sizeof(uint8_t), 2410 [CTLTYPE_U16] = sizeof(uint16_t), 2411 [CTLTYPE_U32] = sizeof(uint32_t), 2412 [CTLTYPE_U64] = sizeof(uint64_t), 2413 }; 2414 2415 #define DB_SYSCTL_NAME_ONLY 0x001 /* Compare with -N */ 2416 #define DB_SYSCTL_VALUE_ONLY 0x002 /* Compare with -n */ 2417 #define DB_SYSCTL_OPAQUE 0x004 /* Compare with -o */ 2418 #define DB_SYSCTL_HEX 0x008 /* Compare with -x */ 2419 2420 #define DB_SYSCTL_SAFE_ONLY 0x100 /* Only simple types */ 2421 2422 static const char db_sysctl_modifs[] = { 2423 'N', 'n', 'o', 'x', 2424 }; 2425 2426 static const int db_sysctl_modif_values[] = { 2427 DB_SYSCTL_NAME_ONLY, DB_SYSCTL_VALUE_ONLY, 2428 DB_SYSCTL_OPAQUE, DB_SYSCTL_HEX, 2429 }; 2430 2431 /* Handlers considered safe to print while recursing */ 2432 static int (* const db_safe_handlers[])(SYSCTL_HANDLER_ARGS) = { 2433 sysctl_handle_bool, 2434 sysctl_handle_8, 2435 sysctl_handle_16, 2436 sysctl_handle_32, 2437 sysctl_handle_64, 2438 sysctl_handle_int, 2439 sysctl_handle_long, 2440 sysctl_handle_string, 2441 sysctl_handle_opaque, 2442 }; 2443 2444 /* 2445 * Use in place of sysctl_old_kernel to print sysctl values. 2446 * 2447 * Compare to the output handling in show_var from sbin/sysctl/sysctl.c 2448 */ 2449 static int 2450 sysctl_old_ddb(struct sysctl_req *req, const void *ptr, size_t len) 2451 { 2452 const u_char *val, *p; 2453 const char *sep1; 2454 size_t intlen, slen; 2455 uintmax_t umv; 2456 intmax_t mv; 2457 int sign, ctltype, hexlen, xflag, error; 2458 2459 /* Suppress false-positive GCC uninitialized variable warnings */ 2460 mv = 0; 2461 umv = 0; 2462 2463 slen = len; 2464 val = p = ptr; 2465 2466 if (ptr == NULL) { 2467 error = 0; 2468 goto out; 2469 } 2470 2471 /* We are going to print */ 2472 g_ddb_sysctl_printed = 1; 2473 2474 xflag = g_ddb_sysctl_flags & DB_SYSCTL_HEX; 2475 2476 ctltype = (g_ddb_oid->oid_kind & CTLTYPE); 2477 sign = ctl_sign[ctltype]; 2478 intlen = ctl_size[ctltype]; 2479 2480 switch (ctltype) { 2481 case CTLTYPE_NODE: 2482 case CTLTYPE_STRING: 2483 db_printf("%.*s", (int) len, (const char *) p); 2484 error = 0; 2485 goto out; 2486 2487 case CTLTYPE_INT: 2488 case CTLTYPE_UINT: 2489 case CTLTYPE_LONG: 2490 case CTLTYPE_ULONG: 2491 case CTLTYPE_S8: 2492 case CTLTYPE_S16: 2493 case CTLTYPE_S32: 2494 case CTLTYPE_S64: 2495 case CTLTYPE_U8: 2496 case CTLTYPE_U16: 2497 case CTLTYPE_U32: 2498 case CTLTYPE_U64: 2499 hexlen = 2 + (intlen * CHAR_BIT + 3) / 4; 2500 sep1 = ""; 2501 while (len >= intlen) { 2502 switch (ctltype) { 2503 case CTLTYPE_INT: 2504 case CTLTYPE_UINT: 2505 umv = *(const u_int *)p; 2506 mv = *(const int *)p; 2507 break; 2508 case CTLTYPE_LONG: 2509 case CTLTYPE_ULONG: 2510 umv = *(const u_long *)p; 2511 mv = *(const long *)p; 2512 break; 2513 case CTLTYPE_S8: 2514 case CTLTYPE_U8: 2515 umv = *(const uint8_t *)p; 2516 mv = *(const int8_t *)p; 2517 break; 2518 case CTLTYPE_S16: 2519 case CTLTYPE_U16: 2520 umv = *(const uint16_t *)p; 2521 mv = *(const int16_t *)p; 2522 break; 2523 case CTLTYPE_S32: 2524 case CTLTYPE_U32: 2525 umv = *(const uint32_t *)p; 2526 mv = *(const int32_t *)p; 2527 break; 2528 case CTLTYPE_S64: 2529 case CTLTYPE_U64: 2530 umv = *(const uint64_t *)p; 2531 mv = *(const int64_t *)p; 2532 break; 2533 } 2534 2535 db_printf("%s", sep1); 2536 if (xflag) 2537 db_printf("%#0*jx", hexlen, umv); 2538 else if (!sign) 2539 db_printf("%ju", umv); 2540 else if (g_ddb_oid->oid_fmt[1] == 'K') { 2541 /* Kelvins are currently unsupported. */ 2542 error = EOPNOTSUPP; 2543 goto out; 2544 } else 2545 db_printf("%jd", mv); 2546 2547 sep1 = " "; 2548 len -= intlen; 2549 p += intlen; 2550 } 2551 error = 0; 2552 goto out; 2553 2554 case CTLTYPE_OPAQUE: 2555 /* TODO: Support struct functions. */ 2556 2557 /* FALLTHROUGH */ 2558 default: 2559 db_printf("Format:%s Length:%zu Dump:0x", 2560 g_ddb_oid->oid_fmt, len); 2561 while (len-- && (xflag || p < val + 16)) 2562 db_printf("%02x", *p++); 2563 if (!xflag && len > 16) 2564 db_printf("..."); 2565 error = 0; 2566 goto out; 2567 } 2568 2569 out: 2570 req->oldidx += slen; 2571 return (error); 2572 } 2573 2574 /* 2575 * Avoid setting new sysctl values from the debugger 2576 */ 2577 static int 2578 sysctl_new_ddb(struct sysctl_req *req, void *p, size_t l) 2579 { 2580 2581 if (!req->newptr) 2582 return (0); 2583 2584 /* Changing sysctls from the debugger is currently unsupported */ 2585 return (EPERM); 2586 } 2587 2588 /* 2589 * Run a sysctl handler with the DDB oldfunc and newfunc attached. 2590 * Instead of copying any output to a buffer we'll dump it right to 2591 * the console. 2592 */ 2593 static int 2594 db_sysctl(struct sysctl_oid *oidp, int *name, u_int namelen, 2595 void *old, size_t *oldlenp, size_t *retval, int flags) 2596 { 2597 struct sysctl_req req; 2598 int error; 2599 2600 /* Setup the request */ 2601 bzero(&req, sizeof req); 2602 req.td = kdb_thread; 2603 req.oldfunc = sysctl_old_ddb; 2604 req.newfunc = sysctl_new_ddb; 2605 req.lock = REQ_UNWIRED; 2606 if (oldlenp) { 2607 req.oldlen = *oldlenp; 2608 } 2609 req.validlen = req.oldlen; 2610 if (old) { 2611 req.oldptr = old; 2612 } 2613 2614 /* Setup our globals for sysctl_old_ddb */ 2615 g_ddb_oid = oidp; 2616 g_ddb_sysctl_flags = flags; 2617 g_ddb_sysctl_printed = 0; 2618 2619 error = sysctl_root(0, name, namelen, &req); 2620 2621 /* Reset globals */ 2622 g_ddb_oid = NULL; 2623 g_ddb_sysctl_flags = 0; 2624 2625 if (retval) { 2626 if (req.oldptr && req.oldidx > req.validlen) 2627 *retval = req.validlen; 2628 else 2629 *retval = req.oldidx; 2630 } 2631 return (error); 2632 } 2633 2634 /* 2635 * Show a sysctl's name 2636 */ 2637 static void 2638 db_show_oid_name(int *oid, size_t nlen) 2639 { 2640 struct sysctl_oid *oidp; 2641 int qoid[CTL_MAXNAME+2]; 2642 int error; 2643 2644 qoid[0] = 0; 2645 memcpy(qoid + 2, oid, nlen * sizeof(int)); 2646 qoid[1] = 1; 2647 2648 error = sysctl_find_oid(qoid, nlen + 2, &oidp, NULL, NULL); 2649 if (error) 2650 db_error("sysctl name oid"); 2651 2652 error = db_sysctl(oidp, qoid, nlen + 2, NULL, NULL, NULL, 0); 2653 if (error) 2654 db_error("sysctl name"); 2655 } 2656 2657 /* 2658 * Check to see if an OID is safe to print from ddb. 2659 */ 2660 static bool 2661 db_oid_safe(const struct sysctl_oid *oidp) 2662 { 2663 for (unsigned int i = 0; i < nitems(db_safe_handlers); ++i) { 2664 if (oidp->oid_handler == db_safe_handlers[i]) 2665 return (true); 2666 } 2667 2668 return (false); 2669 } 2670 2671 /* 2672 * Show a sysctl at a specific OID 2673 * Compare to the input handling in show_var from sbin/sysctl/sysctl.c 2674 */ 2675 static int 2676 db_show_oid(struct sysctl_oid *oidp, int *oid, size_t nlen, int flags) 2677 { 2678 int error, xflag, oflag, Nflag, nflag; 2679 size_t len; 2680 2681 xflag = flags & DB_SYSCTL_HEX; 2682 oflag = flags & DB_SYSCTL_OPAQUE; 2683 nflag = flags & DB_SYSCTL_VALUE_ONLY; 2684 Nflag = flags & DB_SYSCTL_NAME_ONLY; 2685 2686 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_OPAQUE && 2687 (!xflag && !oflag)) 2688 return (0); 2689 2690 if (Nflag) { 2691 db_show_oid_name(oid, nlen); 2692 error = 0; 2693 goto out; 2694 } 2695 2696 if (!nflag) { 2697 db_show_oid_name(oid, nlen); 2698 db_printf(": "); 2699 } 2700 2701 if ((flags & DB_SYSCTL_SAFE_ONLY) && !db_oid_safe(oidp)) { 2702 db_printf("Skipping, unsafe to print while recursing."); 2703 error = 0; 2704 goto out; 2705 } 2706 2707 /* Try once, and ask about the size */ 2708 len = 0; 2709 error = db_sysctl(oidp, oid, nlen, 2710 NULL, NULL, &len, flags); 2711 if (error) 2712 goto out; 2713 2714 if (!g_ddb_sysctl_printed) 2715 /* Lie about the size */ 2716 error = db_sysctl(oidp, oid, nlen, 2717 (void *) 1, &len, NULL, flags); 2718 2719 out: 2720 db_printf("\n"); 2721 return (error); 2722 } 2723 2724 /* 2725 * Show all sysctls under a specific OID 2726 * Compare to sysctl_all from sbin/sysctl/sysctl.c 2727 */ 2728 static int 2729 db_show_sysctl_all(int *oid, size_t len, int flags) 2730 { 2731 struct sysctl_oid *oidp; 2732 int name1[CTL_MAXNAME + 2], name2[CTL_MAXNAME + 2]; 2733 size_t l1, l2; 2734 2735 name1[0] = CTL_SYSCTL; 2736 name1[1] = CTL_SYSCTL_NEXT; 2737 l1 = 2; 2738 if (len) { 2739 memcpy(name1 + 2, oid, len * sizeof(int)); 2740 l1 += len; 2741 } else { 2742 name1[2] = CTL_KERN; 2743 l1++; 2744 } 2745 for (;;) { 2746 int i, error; 2747 2748 l2 = sizeof(name2); 2749 error = kernel_sysctl(kdb_thread, name1, l1, 2750 name2, &l2, NULL, 0, &l2, 0); 2751 if (error != 0) { 2752 if (error == ENOENT) 2753 return (0); 2754 else 2755 db_error("sysctl(next)"); 2756 } 2757 2758 l2 /= sizeof(int); 2759 2760 if (l2 < (unsigned int)len) 2761 return (0); 2762 2763 for (i = 0; i < len; i++) 2764 if (name2[i] != oid[i]) 2765 return (0); 2766 2767 /* Find the OID in question */ 2768 error = sysctl_find_oid(name2, l2, &oidp, NULL, NULL); 2769 if (error) 2770 return (error); 2771 2772 i = db_show_oid(oidp, name2, l2, flags | DB_SYSCTL_SAFE_ONLY); 2773 2774 if (db_pager_quit) 2775 return (0); 2776 2777 memcpy(name1+2, name2, l2 * sizeof(int)); 2778 l1 = 2 + l2; 2779 } 2780 } 2781 2782 /* 2783 * Show a sysctl by its user facing string 2784 */ 2785 static int 2786 db_sysctlbyname(char *name, int flags) 2787 { 2788 struct sysctl_oid *oidp; 2789 int oid[CTL_MAXNAME]; 2790 int error, nlen; 2791 2792 error = name2oid(name, oid, &nlen, &oidp); 2793 if (error) { 2794 return (error); 2795 } 2796 2797 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2798 db_show_sysctl_all(oid, nlen, flags); 2799 } else { 2800 error = db_show_oid(oidp, oid, nlen, flags); 2801 } 2802 2803 return (error); 2804 } 2805 2806 static void 2807 db_sysctl_cmd_usage(void) 2808 { 2809 db_printf( 2810 " sysctl [/Nnox] <sysctl> \n" 2811 " \n" 2812 " <sysctl> The name of the sysctl to show. \n" 2813 " \n" 2814 " Show a sysctl by hooking into SYSCTL_IN and SYSCTL_OUT. \n" 2815 " This will work for most sysctls, but should not be used \n" 2816 " with sysctls that are known to malloc. \n" 2817 " \n" 2818 " While recursing any \"unsafe\" sysctls will be skipped. \n" 2819 " Call sysctl directly on the sysctl to try printing the \n" 2820 " skipped sysctl. This is unsafe and may make the ddb \n" 2821 " session unusable. \n" 2822 " \n" 2823 " Arguments: \n" 2824 " /N Display only the name of the sysctl. \n" 2825 " /n Display only the value of the sysctl. \n" 2826 " /o Display opaque values. \n" 2827 " /x Display the sysctl in hex. \n" 2828 " \n" 2829 "For example: \n" 2830 "sysctl vm.v_free_min \n" 2831 "vn.v_free_min: 12669 \n" 2832 ); 2833 } 2834 2835 /* 2836 * Show a specific sysctl similar to sysctl (8). 2837 */ 2838 DB_FUNC(sysctl, db_sysctl_cmd, db_cmd_table, CS_OWN, NULL) 2839 { 2840 char name[TOK_STRING_SIZE]; 2841 int error, i, t, flags; 2842 2843 /* Parse the modifiers */ 2844 t = db_read_token(); 2845 if (t == tSLASH || t == tMINUS) { 2846 t = db_read_token(); 2847 if (t != tIDENT) { 2848 db_printf("Bad modifier\n"); 2849 error = EINVAL; 2850 goto out; 2851 } 2852 db_strcpy(modif, db_tok_string); 2853 } 2854 else { 2855 db_unread_token(t); 2856 modif[0] = '\0'; 2857 } 2858 2859 flags = 0; 2860 for (i = 0; i < nitems(db_sysctl_modifs); i++) { 2861 if (strchr(modif, db_sysctl_modifs[i])) { 2862 flags |= db_sysctl_modif_values[i]; 2863 } 2864 } 2865 2866 /* Parse the sysctl names */ 2867 t = db_read_token(); 2868 if (t != tIDENT) { 2869 db_printf("Need sysctl name\n"); 2870 error = EINVAL; 2871 goto out; 2872 } 2873 2874 /* Copy the name into a temporary buffer */ 2875 db_strcpy(name, db_tok_string); 2876 2877 /* Ensure there is no trailing cruft */ 2878 t = db_read_token(); 2879 if (t != tEOL) { 2880 db_printf("Unexpected sysctl argument\n"); 2881 error = EINVAL; 2882 goto out; 2883 } 2884 2885 error = db_sysctlbyname(name, flags); 2886 if (error == ENOENT) { 2887 db_printf("unknown oid: '%s'\n", db_tok_string); 2888 goto out; 2889 } else if (error) { 2890 db_printf("%s: error: %d\n", db_tok_string, error); 2891 goto out; 2892 } 2893 2894 out: 2895 /* Ensure we eat all of our text */ 2896 db_flush_lex(); 2897 2898 if (error == EINVAL) { 2899 db_sysctl_cmd_usage(); 2900 } 2901 } 2902 2903 #endif /* DDB */ 2904