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. 954 * {CTL_SYSCTL, CTL_SYSCTL_NAME2OID} return the OID of the name in 955 * "new" 956 * {CTL_SYSCTL, CTL_SYSCTL_OIDFMT, ...} return the kind & format info 957 * for the "..." OID. 958 * {CTL_SYSCTL, CTL_SYSCTL_OIDDESCR, ...} return the description of the 959 * "..." OID. 960 * {CTL_SYSCTL, CTL_SYSCTL_OIDLABEL, ...} return the aggregation label of 961 * the "..." OID. 962 */ 963 964 #ifdef SYSCTL_DEBUG 965 static void 966 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 967 { 968 int k; 969 struct sysctl_oid *oidp; 970 971 SYSCTL_ASSERT_LOCKED(); 972 SLIST_FOREACH(oidp, l, oid_link) { 973 974 for (k=0; k<i; k++) 975 printf(" "); 976 977 printf("%d %s ", oidp->oid_number, oidp->oid_name); 978 979 printf("%c%c", 980 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 981 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 982 983 if (oidp->oid_handler) 984 printf(" *Handler"); 985 986 switch (oidp->oid_kind & CTLTYPE) { 987 case CTLTYPE_NODE: 988 printf(" Node\n"); 989 if (!oidp->oid_handler) { 990 sysctl_sysctl_debug_dump_node( 991 SYSCTL_CHILDREN(oidp), i + 2); 992 } 993 break; 994 case CTLTYPE_INT: printf(" Int\n"); break; 995 case CTLTYPE_UINT: printf(" u_int\n"); break; 996 case CTLTYPE_LONG: printf(" Long\n"); break; 997 case CTLTYPE_ULONG: printf(" u_long\n"); break; 998 case CTLTYPE_STRING: printf(" String\n"); break; 999 case CTLTYPE_S8: printf(" int8_t\n"); break; 1000 case CTLTYPE_S16: printf(" int16_t\n"); break; 1001 case CTLTYPE_S32: printf(" int32_t\n"); break; 1002 case CTLTYPE_S64: printf(" int64_t\n"); break; 1003 case CTLTYPE_U8: printf(" uint8_t\n"); break; 1004 case CTLTYPE_U16: printf(" uint16_t\n"); break; 1005 case CTLTYPE_U32: printf(" uint32_t\n"); break; 1006 case CTLTYPE_U64: printf(" uint64_t\n"); break; 1007 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; 1008 default: printf("\n"); 1009 } 1010 1011 } 1012 } 1013 1014 static int 1015 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 1016 { 1017 struct rm_priotracker tracker; 1018 int error; 1019 1020 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 1021 if (error) 1022 return (error); 1023 SYSCTL_RLOCK(&tracker); 1024 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 1025 SYSCTL_RUNLOCK(&tracker); 1026 return (ENOENT); 1027 } 1028 1029 SYSCTL_PROC(_sysctl, CTL_SYSCTL_DEBUG, debug, CTLTYPE_STRING | CTLFLAG_RD | 1030 CTLFLAG_MPSAFE, 0, 0, sysctl_sysctl_debug, "-", ""); 1031 #endif 1032 1033 static int 1034 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 1035 { 1036 int *name = (int *) arg1; 1037 u_int namelen = arg2; 1038 int error; 1039 struct sysctl_oid *oid; 1040 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 1041 struct rm_priotracker tracker; 1042 char buf[10]; 1043 1044 error = sysctl_wire_old_buffer(req, 0); 1045 if (error) 1046 return (error); 1047 1048 SYSCTL_RLOCK(&tracker); 1049 while (namelen) { 1050 if (!lsp) { 1051 snprintf(buf,sizeof(buf),"%d",*name); 1052 if (req->oldidx) 1053 error = SYSCTL_OUT(req, ".", 1); 1054 if (!error) 1055 error = SYSCTL_OUT(req, buf, strlen(buf)); 1056 if (error) 1057 goto out; 1058 namelen--; 1059 name++; 1060 continue; 1061 } 1062 lsp2 = NULL; 1063 SLIST_FOREACH(oid, lsp, oid_link) { 1064 if (oid->oid_number != *name) 1065 continue; 1066 1067 if (req->oldidx) 1068 error = SYSCTL_OUT(req, ".", 1); 1069 if (!error) 1070 error = SYSCTL_OUT(req, oid->oid_name, 1071 strlen(oid->oid_name)); 1072 if (error) 1073 goto out; 1074 1075 namelen--; 1076 name++; 1077 1078 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1079 break; 1080 1081 if (oid->oid_handler) 1082 break; 1083 1084 lsp2 = SYSCTL_CHILDREN(oid); 1085 break; 1086 } 1087 lsp = lsp2; 1088 } 1089 error = SYSCTL_OUT(req, "", 1); 1090 out: 1091 SYSCTL_RUNLOCK(&tracker); 1092 return (error); 1093 } 1094 1095 /* 1096 * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in 1097 * capability mode. 1098 */ 1099 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NAME, name, CTLFLAG_RD | 1100 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_name, ""); 1101 1102 static int 1103 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 1104 int *next, int *len, int level, struct sysctl_oid **oidpp) 1105 { 1106 struct sysctl_oid *oidp; 1107 1108 SYSCTL_ASSERT_LOCKED(); 1109 *len = level; 1110 SLIST_FOREACH(oidp, lsp, oid_link) { 1111 *next = oidp->oid_number; 1112 *oidpp = oidp; 1113 1114 if ((oidp->oid_kind & (CTLFLAG_SKIP | CTLFLAG_DORMANT)) != 0) 1115 continue; 1116 1117 if (!namelen) { 1118 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1119 return (0); 1120 if (oidp->oid_handler) 1121 /* We really should call the handler here...*/ 1122 return (0); 1123 lsp = SYSCTL_CHILDREN(oidp); 1124 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 1125 len, level+1, oidpp)) 1126 return (0); 1127 goto emptynode; 1128 } 1129 1130 if (oidp->oid_number < *name) 1131 continue; 1132 1133 if (oidp->oid_number > *name) { 1134 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1135 return (0); 1136 if (oidp->oid_handler) 1137 return (0); 1138 lsp = SYSCTL_CHILDREN(oidp); 1139 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 1140 next+1, len, level+1, oidpp)) 1141 return (0); 1142 goto next; 1143 } 1144 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1145 continue; 1146 1147 if (oidp->oid_handler) 1148 continue; 1149 1150 lsp = SYSCTL_CHILDREN(oidp); 1151 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 1152 len, level+1, oidpp)) 1153 return (0); 1154 next: 1155 namelen = 1; 1156 emptynode: 1157 *len = level; 1158 } 1159 return (1); 1160 } 1161 1162 static int 1163 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 1164 { 1165 int *name = (int *) arg1; 1166 u_int namelen = arg2; 1167 int i, j, error; 1168 struct sysctl_oid *oid; 1169 struct sysctl_oid_list *lsp = &sysctl__children; 1170 struct rm_priotracker tracker; 1171 int newoid[CTL_MAXNAME]; 1172 1173 SYSCTL_RLOCK(&tracker); 1174 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 1175 SYSCTL_RUNLOCK(&tracker); 1176 if (i) 1177 return (ENOENT); 1178 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 1179 return (error); 1180 } 1181 1182 /* 1183 * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in 1184 * capability mode. 1185 */ 1186 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXT, next, CTLFLAG_RD | 1187 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, ""); 1188 1189 static int 1190 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) 1191 { 1192 struct sysctl_oid *oidp; 1193 struct sysctl_oid_list *lsp = &sysctl__children; 1194 char *p; 1195 1196 SYSCTL_ASSERT_LOCKED(); 1197 1198 for (*len = 0; *len < CTL_MAXNAME;) { 1199 p = strsep(&name, "."); 1200 1201 oidp = SLIST_FIRST(lsp); 1202 for (;; oidp = SLIST_NEXT(oidp, oid_link)) { 1203 if (oidp == NULL) 1204 return (ENOENT); 1205 if (strcmp(p, oidp->oid_name) == 0) 1206 break; 1207 } 1208 *oid++ = oidp->oid_number; 1209 (*len)++; 1210 1211 if (name == NULL || *name == '\0') { 1212 if (oidpp) 1213 *oidpp = oidp; 1214 return (0); 1215 } 1216 1217 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1218 break; 1219 1220 if (oidp->oid_handler) 1221 break; 1222 1223 lsp = SYSCTL_CHILDREN(oidp); 1224 } 1225 return (ENOENT); 1226 } 1227 1228 static int 1229 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 1230 { 1231 char *p; 1232 int error, oid[CTL_MAXNAME], len = 0; 1233 struct sysctl_oid *op = NULL; 1234 struct rm_priotracker tracker; 1235 char buf[32]; 1236 1237 if (!req->newlen) 1238 return (ENOENT); 1239 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 1240 return (ENAMETOOLONG); 1241 1242 p = buf; 1243 if (req->newlen >= sizeof(buf)) 1244 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); 1245 1246 error = SYSCTL_IN(req, p, req->newlen); 1247 if (error) { 1248 if (p != buf) 1249 free(p, M_SYSCTL); 1250 return (error); 1251 } 1252 1253 p [req->newlen] = '\0'; 1254 1255 SYSCTL_RLOCK(&tracker); 1256 error = name2oid(p, oid, &len, &op); 1257 SYSCTL_RUNLOCK(&tracker); 1258 1259 if (p != buf) 1260 free(p, M_SYSCTL); 1261 1262 if (error) 1263 return (error); 1264 1265 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 1266 return (error); 1267 } 1268 1269 /* 1270 * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in 1271 * capability mode. 1272 */ 1273 SYSCTL_PROC(_sysctl, CTL_SYSCTL_NAME2OID, name2oid, CTLTYPE_INT | CTLFLAG_RW | 1274 CTLFLAG_ANYBODY | CTLFLAG_MPSAFE | CTLFLAG_CAPRW, 0, 0, 1275 sysctl_sysctl_name2oid, "I", ""); 1276 1277 static int 1278 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 1279 { 1280 struct sysctl_oid *oid; 1281 struct rm_priotracker tracker; 1282 int error; 1283 1284 error = sysctl_wire_old_buffer(req, 0); 1285 if (error) 1286 return (error); 1287 1288 SYSCTL_RLOCK(&tracker); 1289 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1290 if (error) 1291 goto out; 1292 1293 if (oid->oid_fmt == NULL) { 1294 error = ENOENT; 1295 goto out; 1296 } 1297 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 1298 if (error) 1299 goto out; 1300 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 1301 out: 1302 SYSCTL_RUNLOCK(&tracker); 1303 return (error); 1304 } 1305 1306 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDFMT, oidfmt, CTLFLAG_RD | 1307 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidfmt, ""); 1308 1309 static int 1310 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 1311 { 1312 struct sysctl_oid *oid; 1313 struct rm_priotracker tracker; 1314 int error; 1315 1316 error = sysctl_wire_old_buffer(req, 0); 1317 if (error) 1318 return (error); 1319 1320 SYSCTL_RLOCK(&tracker); 1321 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1322 if (error) 1323 goto out; 1324 1325 if (oid->oid_descr == NULL) { 1326 error = ENOENT; 1327 goto out; 1328 } 1329 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 1330 out: 1331 SYSCTL_RUNLOCK(&tracker); 1332 return (error); 1333 } 1334 1335 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDDESCR, oiddescr, CTLFLAG_RD | 1336 CTLFLAG_MPSAFE|CTLFLAG_CAPRD, sysctl_sysctl_oiddescr, ""); 1337 1338 static int 1339 sysctl_sysctl_oidlabel(SYSCTL_HANDLER_ARGS) 1340 { 1341 struct sysctl_oid *oid; 1342 struct rm_priotracker tracker; 1343 int error; 1344 1345 error = sysctl_wire_old_buffer(req, 0); 1346 if (error) 1347 return (error); 1348 1349 SYSCTL_RLOCK(&tracker); 1350 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1351 if (error) 1352 goto out; 1353 1354 if (oid->oid_label == NULL) { 1355 error = ENOENT; 1356 goto out; 1357 } 1358 error = SYSCTL_OUT(req, oid->oid_label, strlen(oid->oid_label) + 1); 1359 out: 1360 SYSCTL_RUNLOCK(&tracker); 1361 return (error); 1362 } 1363 1364 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDLABEL, oidlabel, CTLFLAG_RD | 1365 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidlabel, ""); 1366 1367 /* 1368 * Default "handler" functions. 1369 */ 1370 1371 /* 1372 * Handle a bool. 1373 * Two cases: 1374 * a variable: point arg1 at it. 1375 * a constant: pass it in arg2. 1376 */ 1377 1378 int 1379 sysctl_handle_bool(SYSCTL_HANDLER_ARGS) 1380 { 1381 uint8_t temp; 1382 int error; 1383 1384 /* 1385 * Attempt to get a coherent snapshot by making a copy of the data. 1386 */ 1387 if (arg1) 1388 temp = *(bool *)arg1 ? 1 : 0; 1389 else 1390 temp = arg2 ? 1 : 0; 1391 1392 error = SYSCTL_OUT(req, &temp, sizeof(temp)); 1393 if (error || !req->newptr) 1394 return (error); 1395 1396 if (!arg1) 1397 error = EPERM; 1398 else { 1399 error = SYSCTL_IN(req, &temp, sizeof(temp)); 1400 if (!error) 1401 *(bool *)arg1 = temp ? 1 : 0; 1402 } 1403 return (error); 1404 } 1405 1406 /* 1407 * Handle an int8_t, signed or unsigned. 1408 * Two cases: 1409 * a variable: point arg1 at it. 1410 * a constant: pass it in arg2. 1411 */ 1412 1413 int 1414 sysctl_handle_8(SYSCTL_HANDLER_ARGS) 1415 { 1416 int8_t tmpout; 1417 int error = 0; 1418 1419 /* 1420 * Attempt to get a coherent snapshot by making a copy of the data. 1421 */ 1422 if (arg1) 1423 tmpout = *(int8_t *)arg1; 1424 else 1425 tmpout = arg2; 1426 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1427 1428 if (error || !req->newptr) 1429 return (error); 1430 1431 if (!arg1) 1432 error = EPERM; 1433 else 1434 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1435 return (error); 1436 } 1437 1438 /* 1439 * Handle an int16_t, signed or unsigned. 1440 * Two cases: 1441 * a variable: point arg1 at it. 1442 * a constant: pass it in arg2. 1443 */ 1444 1445 int 1446 sysctl_handle_16(SYSCTL_HANDLER_ARGS) 1447 { 1448 int16_t tmpout; 1449 int error = 0; 1450 1451 /* 1452 * Attempt to get a coherent snapshot by making a copy of the data. 1453 */ 1454 if (arg1) 1455 tmpout = *(int16_t *)arg1; 1456 else 1457 tmpout = arg2; 1458 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1459 1460 if (error || !req->newptr) 1461 return (error); 1462 1463 if (!arg1) 1464 error = EPERM; 1465 else 1466 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1467 return (error); 1468 } 1469 1470 /* 1471 * Handle an int32_t, signed or unsigned. 1472 * Two cases: 1473 * a variable: point arg1 at it. 1474 * a constant: pass it in arg2. 1475 */ 1476 1477 int 1478 sysctl_handle_32(SYSCTL_HANDLER_ARGS) 1479 { 1480 int32_t tmpout; 1481 int error = 0; 1482 1483 /* 1484 * Attempt to get a coherent snapshot by making a copy of the data. 1485 */ 1486 if (arg1) 1487 tmpout = *(int32_t *)arg1; 1488 else 1489 tmpout = arg2; 1490 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1491 1492 if (error || !req->newptr) 1493 return (error); 1494 1495 if (!arg1) 1496 error = EPERM; 1497 else 1498 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1499 return (error); 1500 } 1501 1502 /* 1503 * Handle an int, signed or unsigned. 1504 * Two cases: 1505 * a variable: point arg1 at it. 1506 * a constant: pass it in arg2. 1507 */ 1508 1509 int 1510 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 1511 { 1512 int tmpout, error = 0; 1513 1514 /* 1515 * Attempt to get a coherent snapshot by making a copy of the data. 1516 */ 1517 if (arg1) 1518 tmpout = *(int *)arg1; 1519 else 1520 tmpout = arg2; 1521 error = SYSCTL_OUT(req, &tmpout, sizeof(int)); 1522 1523 if (error || !req->newptr) 1524 return (error); 1525 1526 if (!arg1) 1527 error = EPERM; 1528 else 1529 error = SYSCTL_IN(req, arg1, sizeof(int)); 1530 return (error); 1531 } 1532 1533 /* 1534 * Based on on sysctl_handle_int() convert milliseconds into ticks. 1535 * Note: this is used by TCP. 1536 */ 1537 1538 int 1539 sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) 1540 { 1541 int error, s, tt; 1542 1543 tt = *(int *)arg1; 1544 s = (int)((int64_t)tt * 1000 / hz); 1545 1546 error = sysctl_handle_int(oidp, &s, 0, req); 1547 if (error || !req->newptr) 1548 return (error); 1549 1550 tt = (int)((int64_t)s * hz / 1000); 1551 if (tt < 1) 1552 return (EINVAL); 1553 1554 *(int *)arg1 = tt; 1555 return (0); 1556 } 1557 1558 /* 1559 * Handle a long, signed or unsigned. 1560 * Two cases: 1561 * a variable: point arg1 at it. 1562 * a constant: pass it in arg2. 1563 */ 1564 1565 int 1566 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 1567 { 1568 int error = 0; 1569 long tmplong; 1570 #ifdef SCTL_MASK32 1571 int tmpint; 1572 #endif 1573 1574 /* 1575 * Attempt to get a coherent snapshot by making a copy of the data. 1576 */ 1577 if (arg1) 1578 tmplong = *(long *)arg1; 1579 else 1580 tmplong = arg2; 1581 #ifdef SCTL_MASK32 1582 if (req->flags & SCTL_MASK32) { 1583 tmpint = tmplong; 1584 error = SYSCTL_OUT(req, &tmpint, sizeof(int)); 1585 } else 1586 #endif 1587 error = SYSCTL_OUT(req, &tmplong, sizeof(long)); 1588 1589 if (error || !req->newptr) 1590 return (error); 1591 1592 if (!arg1) 1593 error = EPERM; 1594 #ifdef SCTL_MASK32 1595 else if (req->flags & SCTL_MASK32) { 1596 error = SYSCTL_IN(req, &tmpint, sizeof(int)); 1597 *(long *)arg1 = (long)tmpint; 1598 } 1599 #endif 1600 else 1601 error = SYSCTL_IN(req, arg1, sizeof(long)); 1602 return (error); 1603 } 1604 1605 /* 1606 * Handle a 64 bit int, signed or unsigned. 1607 * Two cases: 1608 * a variable: point arg1 at it. 1609 * a constant: pass it in arg2. 1610 */ 1611 int 1612 sysctl_handle_64(SYSCTL_HANDLER_ARGS) 1613 { 1614 int error = 0; 1615 uint64_t tmpout; 1616 1617 /* 1618 * Attempt to get a coherent snapshot by making a copy of the data. 1619 */ 1620 if (arg1) 1621 tmpout = *(uint64_t *)arg1; 1622 else 1623 tmpout = arg2; 1624 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t)); 1625 1626 if (error || !req->newptr) 1627 return (error); 1628 1629 if (!arg1) 1630 error = EPERM; 1631 else 1632 error = SYSCTL_IN(req, arg1, sizeof(uint64_t)); 1633 return (error); 1634 } 1635 1636 /* 1637 * Handle our generic '\0' terminated 'C' string. 1638 * Two cases: 1639 * a variable string: point arg1 at it, arg2 is max length. 1640 * a constant string: point arg1 at it, arg2 is zero. 1641 */ 1642 1643 int 1644 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 1645 { 1646 char *tmparg; 1647 size_t outlen; 1648 int error = 0, ro_string = 0; 1649 1650 /* 1651 * If the sysctl isn't writable and isn't a preallocated tunable that 1652 * can be modified by kenv(2), microoptimise and treat it as a 1653 * read-only string. 1654 * A zero-length buffer indicates a fixed size read-only 1655 * string. In ddb, don't worry about trying to make a malloced 1656 * snapshot. 1657 */ 1658 if ((oidp->oid_kind & (CTLFLAG_WR | CTLFLAG_TUN)) == 0 || 1659 arg2 == 0 || kdb_active) { 1660 arg2 = strlen((char *)arg1) + 1; 1661 ro_string = 1; 1662 } 1663 1664 if (req->oldptr != NULL) { 1665 if (ro_string) { 1666 tmparg = arg1; 1667 outlen = strlen(tmparg) + 1; 1668 } else { 1669 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1670 sx_slock(&sysctlstringlock); 1671 memcpy(tmparg, arg1, arg2); 1672 sx_sunlock(&sysctlstringlock); 1673 outlen = strlen(tmparg) + 1; 1674 } 1675 1676 error = SYSCTL_OUT(req, tmparg, outlen); 1677 1678 if (!ro_string) 1679 free(tmparg, M_SYSCTLTMP); 1680 } else { 1681 if (!ro_string) 1682 sx_slock(&sysctlstringlock); 1683 outlen = strlen((char *)arg1) + 1; 1684 if (!ro_string) 1685 sx_sunlock(&sysctlstringlock); 1686 error = SYSCTL_OUT(req, NULL, outlen); 1687 } 1688 if (error || !req->newptr) 1689 return (error); 1690 1691 if (req->newlen - req->newidx >= arg2 || 1692 req->newlen - req->newidx < 0) { 1693 error = EINVAL; 1694 } else if (req->newlen - req->newidx == 0) { 1695 sx_xlock(&sysctlstringlock); 1696 ((char *)arg1)[0] = '\0'; 1697 sx_xunlock(&sysctlstringlock); 1698 } else { 1699 arg2 = req->newlen - req->newidx; 1700 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1701 1702 error = SYSCTL_IN(req, tmparg, arg2); 1703 if (error) { 1704 free(tmparg, M_SYSCTLTMP); 1705 return (error); 1706 } 1707 1708 sx_xlock(&sysctlstringlock); 1709 memcpy(arg1, tmparg, arg2); 1710 ((char *)arg1)[arg2] = '\0'; 1711 sx_xunlock(&sysctlstringlock); 1712 free(tmparg, M_SYSCTLTMP); 1713 req->newidx += arg2; 1714 } 1715 return (error); 1716 } 1717 1718 /* 1719 * Handle any kind of opaque data. 1720 * arg1 points to it, arg2 is the size. 1721 */ 1722 1723 int 1724 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 1725 { 1726 int error, tries; 1727 u_int generation; 1728 struct sysctl_req req2; 1729 1730 /* 1731 * Attempt to get a coherent snapshot, by using the thread 1732 * pre-emption counter updated from within mi_switch() to 1733 * determine if we were pre-empted during a bcopy() or 1734 * copyout(). Make 3 attempts at doing this before giving up. 1735 * If we encounter an error, stop immediately. 1736 */ 1737 tries = 0; 1738 req2 = *req; 1739 retry: 1740 generation = curthread->td_generation; 1741 error = SYSCTL_OUT(req, arg1, arg2); 1742 if (error) 1743 return (error); 1744 tries++; 1745 if (generation != curthread->td_generation && tries < 3) { 1746 *req = req2; 1747 goto retry; 1748 } 1749 1750 error = SYSCTL_IN(req, arg1, arg2); 1751 1752 return (error); 1753 } 1754 1755 /* 1756 * Based on on sysctl_handle_int() convert microseconds to a sbintime. 1757 */ 1758 int 1759 sysctl_usec_to_sbintime(SYSCTL_HANDLER_ARGS) 1760 { 1761 int error; 1762 int64_t tt; 1763 sbintime_t sb; 1764 1765 tt = *(int64_t *)arg1; 1766 sb = sbttous(tt); 1767 1768 error = sysctl_handle_64(oidp, &sb, 0, req); 1769 if (error || !req->newptr) 1770 return (error); 1771 1772 tt = ustosbt(sb); 1773 *(int64_t *)arg1 = tt; 1774 1775 return (0); 1776 } 1777 1778 /* 1779 * Based on on sysctl_handle_int() convert milliseconds to a sbintime. 1780 */ 1781 int 1782 sysctl_msec_to_sbintime(SYSCTL_HANDLER_ARGS) 1783 { 1784 int error; 1785 int64_t tt; 1786 sbintime_t sb; 1787 1788 tt = *(int64_t *)arg1; 1789 sb = sbttoms(tt); 1790 1791 error = sysctl_handle_64(oidp, &sb, 0, req); 1792 if (error || !req->newptr) 1793 return (error); 1794 1795 tt = mstosbt(sb); 1796 *(int64_t *)arg1 = tt; 1797 1798 return (0); 1799 } 1800 1801 /* 1802 * Convert seconds to a struct timeval. Intended for use with 1803 * intervals and thus does not permit negative seconds. 1804 */ 1805 int 1806 sysctl_sec_to_timeval(SYSCTL_HANDLER_ARGS) 1807 { 1808 struct timeval *tv; 1809 int error, secs; 1810 1811 tv = arg1; 1812 secs = tv->tv_sec; 1813 1814 error = sysctl_handle_int(oidp, &secs, 0, req); 1815 if (error || req->newptr == NULL) 1816 return (error); 1817 1818 if (secs < 0) 1819 return (EINVAL); 1820 tv->tv_sec = secs; 1821 1822 return (0); 1823 } 1824 1825 /* 1826 * Transfer functions to/from kernel space. 1827 * XXX: rather untested at this point 1828 */ 1829 static int 1830 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 1831 { 1832 size_t i = 0; 1833 1834 if (req->oldptr) { 1835 i = l; 1836 if (req->oldlen <= req->oldidx) 1837 i = 0; 1838 else 1839 if (i > req->oldlen - req->oldidx) 1840 i = req->oldlen - req->oldidx; 1841 if (i > 0) 1842 bcopy(p, (char *)req->oldptr + req->oldidx, i); 1843 } 1844 req->oldidx += l; 1845 if (req->oldptr && i != l) 1846 return (ENOMEM); 1847 return (0); 1848 } 1849 1850 static int 1851 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 1852 { 1853 if (!req->newptr) 1854 return (0); 1855 if (req->newlen - req->newidx < l) 1856 return (EINVAL); 1857 bcopy((const char *)req->newptr + req->newidx, p, l); 1858 req->newidx += l; 1859 return (0); 1860 } 1861 1862 int 1863 kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1864 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) 1865 { 1866 int error = 0; 1867 struct sysctl_req req; 1868 1869 bzero(&req, sizeof req); 1870 1871 req.td = td; 1872 req.flags = flags; 1873 1874 if (oldlenp) { 1875 req.oldlen = *oldlenp; 1876 } 1877 req.validlen = req.oldlen; 1878 1879 if (old) { 1880 req.oldptr= old; 1881 } 1882 1883 if (new != NULL) { 1884 req.newlen = newlen; 1885 req.newptr = new; 1886 } 1887 1888 req.oldfunc = sysctl_old_kernel; 1889 req.newfunc = sysctl_new_kernel; 1890 req.lock = REQ_UNWIRED; 1891 1892 error = sysctl_root(0, name, namelen, &req); 1893 1894 if (req.lock == REQ_WIRED && req.validlen > 0) 1895 vsunlock(req.oldptr, req.validlen); 1896 1897 if (error && error != ENOMEM) 1898 return (error); 1899 1900 if (retval) { 1901 if (req.oldptr && req.oldidx > req.validlen) 1902 *retval = req.validlen; 1903 else 1904 *retval = req.oldidx; 1905 } 1906 return (error); 1907 } 1908 1909 int 1910 kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp, 1911 void *new, size_t newlen, size_t *retval, int flags) 1912 { 1913 int oid[CTL_MAXNAME]; 1914 size_t oidlen, plen; 1915 int error; 1916 1917 oid[0] = CTL_SYSCTL; 1918 oid[1] = CTL_SYSCTL_NAME2OID; 1919 oidlen = sizeof(oid); 1920 1921 error = kernel_sysctl(td, oid, 2, oid, &oidlen, 1922 (void *)name, strlen(name), &plen, flags); 1923 if (error) 1924 return (error); 1925 1926 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp, 1927 new, newlen, retval, flags); 1928 return (error); 1929 } 1930 1931 /* 1932 * Transfer function to/from user space. 1933 */ 1934 static int 1935 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1936 { 1937 size_t i, len, origidx; 1938 int error; 1939 1940 origidx = req->oldidx; 1941 req->oldidx += l; 1942 if (req->oldptr == NULL) 1943 return (0); 1944 /* 1945 * If we have not wired the user supplied buffer and we are currently 1946 * holding locks, drop a witness warning, as it's possible that 1947 * write operations to the user page can sleep. 1948 */ 1949 if (req->lock != REQ_WIRED) 1950 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1951 "sysctl_old_user()"); 1952 i = l; 1953 len = req->validlen; 1954 if (len <= origidx) 1955 i = 0; 1956 else { 1957 if (i > len - origidx) 1958 i = len - origidx; 1959 if (req->lock == REQ_WIRED) { 1960 error = copyout_nofault(p, (char *)req->oldptr + 1961 origidx, i); 1962 } else 1963 error = copyout(p, (char *)req->oldptr + origidx, i); 1964 if (error != 0) 1965 return (error); 1966 } 1967 if (i < l) 1968 return (ENOMEM); 1969 return (0); 1970 } 1971 1972 static int 1973 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1974 { 1975 int error; 1976 1977 if (!req->newptr) 1978 return (0); 1979 if (req->newlen - req->newidx < l) 1980 return (EINVAL); 1981 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1982 "sysctl_new_user()"); 1983 error = copyin((const char *)req->newptr + req->newidx, p, l); 1984 req->newidx += l; 1985 return (error); 1986 } 1987 1988 /* 1989 * Wire the user space destination buffer. If set to a value greater than 1990 * zero, the len parameter limits the maximum amount of wired memory. 1991 */ 1992 int 1993 sysctl_wire_old_buffer(struct sysctl_req *req, size_t len) 1994 { 1995 int ret; 1996 size_t wiredlen; 1997 1998 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen; 1999 ret = 0; 2000 if (req->lock != REQ_WIRED && req->oldptr && 2001 req->oldfunc == sysctl_old_user) { 2002 if (wiredlen != 0) { 2003 ret = vslock(req->oldptr, wiredlen); 2004 if (ret != 0) { 2005 if (ret != ENOMEM) 2006 return (ret); 2007 wiredlen = 0; 2008 } 2009 } 2010 req->lock = REQ_WIRED; 2011 req->validlen = wiredlen; 2012 } 2013 return (0); 2014 } 2015 2016 int 2017 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 2018 int *nindx, struct sysctl_req *req) 2019 { 2020 struct sysctl_oid_list *lsp; 2021 struct sysctl_oid *oid; 2022 int indx; 2023 2024 SYSCTL_ASSERT_LOCKED(); 2025 lsp = &sysctl__children; 2026 indx = 0; 2027 while (indx < CTL_MAXNAME) { 2028 SLIST_FOREACH(oid, lsp, oid_link) { 2029 if (oid->oid_number == name[indx]) 2030 break; 2031 } 2032 if (oid == NULL) 2033 return (ENOENT); 2034 2035 indx++; 2036 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2037 if (oid->oid_handler != NULL || indx == namelen) { 2038 *noid = oid; 2039 if (nindx != NULL) 2040 *nindx = indx; 2041 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 2042 ("%s found DYING node %p", __func__, oid)); 2043 return (0); 2044 } 2045 lsp = SYSCTL_CHILDREN(oid); 2046 } else if (indx == namelen) { 2047 if ((oid->oid_kind & CTLFLAG_DORMANT) != 0) 2048 return (ENOENT); 2049 *noid = oid; 2050 if (nindx != NULL) 2051 *nindx = indx; 2052 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 2053 ("%s found DYING node %p", __func__, oid)); 2054 return (0); 2055 } else { 2056 return (ENOTDIR); 2057 } 2058 } 2059 return (ENOENT); 2060 } 2061 2062 /* 2063 * Traverse our tree, and find the right node, execute whatever it points 2064 * to, and return the resulting error code. 2065 */ 2066 2067 static int 2068 sysctl_root(SYSCTL_HANDLER_ARGS) 2069 { 2070 struct sysctl_oid *oid; 2071 struct rm_priotracker tracker; 2072 int error, indx, lvl; 2073 2074 SYSCTL_RLOCK(&tracker); 2075 2076 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 2077 if (error) 2078 goto out; 2079 2080 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2081 /* 2082 * You can't call a sysctl when it's a node, but has 2083 * no handler. Inform the user that it's a node. 2084 * The indx may or may not be the same as namelen. 2085 */ 2086 if (oid->oid_handler == NULL) { 2087 error = EISDIR; 2088 goto out; 2089 } 2090 } 2091 2092 /* Is this sysctl writable? */ 2093 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) { 2094 error = EPERM; 2095 goto out; 2096 } 2097 2098 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL")); 2099 2100 #ifdef CAPABILITY_MODE 2101 /* 2102 * If the process is in capability mode, then don't permit reading or 2103 * writing unless specifically granted for the node. 2104 */ 2105 if (IN_CAPABILITY_MODE(req->td)) { 2106 if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) || 2107 (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) { 2108 error = EPERM; 2109 goto out; 2110 } 2111 } 2112 #endif 2113 2114 /* Is this sysctl sensitive to securelevels? */ 2115 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) { 2116 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE; 2117 error = securelevel_gt(req->td->td_ucred, lvl); 2118 if (error) 2119 goto out; 2120 } 2121 2122 /* Is this sysctl writable by only privileged users? */ 2123 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) { 2124 int priv; 2125 2126 if (oid->oid_kind & CTLFLAG_PRISON) 2127 priv = PRIV_SYSCTL_WRITEJAIL; 2128 #ifdef VIMAGE 2129 else if ((oid->oid_kind & CTLFLAG_VNET) && 2130 prison_owns_vnet(req->td->td_ucred)) 2131 priv = PRIV_SYSCTL_WRITEJAIL; 2132 #endif 2133 else 2134 priv = PRIV_SYSCTL_WRITE; 2135 error = priv_check(req->td, priv); 2136 if (error) 2137 goto out; 2138 } 2139 2140 if (!oid->oid_handler) { 2141 error = EINVAL; 2142 goto out; 2143 } 2144 2145 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2146 arg1 = (int *)arg1 + indx; 2147 arg2 -= indx; 2148 } else { 2149 arg1 = oid->oid_arg1; 2150 arg2 = oid->oid_arg2; 2151 } 2152 #ifdef MAC 2153 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2, 2154 req); 2155 if (error != 0) 2156 goto out; 2157 #endif 2158 #ifdef VIMAGE 2159 if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL) 2160 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1); 2161 #endif 2162 error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker); 2163 2164 out: 2165 SYSCTL_RUNLOCK(&tracker); 2166 return (error); 2167 } 2168 2169 #ifndef _SYS_SYSPROTO_H_ 2170 struct sysctl_args { 2171 int *name; 2172 u_int namelen; 2173 void *old; 2174 size_t *oldlenp; 2175 void *new; 2176 size_t newlen; 2177 }; 2178 #endif 2179 int 2180 sys___sysctl(struct thread *td, struct sysctl_args *uap) 2181 { 2182 int error, i, name[CTL_MAXNAME]; 2183 size_t j; 2184 2185 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 2186 return (EINVAL); 2187 2188 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 2189 if (error) 2190 return (error); 2191 2192 error = userland_sysctl(td, name, uap->namelen, 2193 uap->old, uap->oldlenp, 0, 2194 uap->new, uap->newlen, &j, 0); 2195 if (error && error != ENOMEM) 2196 return (error); 2197 if (uap->oldlenp) { 2198 i = copyout(&j, uap->oldlenp, sizeof(j)); 2199 if (i) 2200 return (i); 2201 } 2202 return (error); 2203 } 2204 2205 int 2206 kern___sysctlbyname(struct thread *td, const char *oname, size_t namelen, 2207 void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval, 2208 int flags, bool inkernel) 2209 { 2210 int oid[CTL_MAXNAME]; 2211 char namebuf[16]; 2212 char *name; 2213 size_t oidlen; 2214 int error; 2215 2216 if (namelen > MAXPATHLEN || namelen == 0) 2217 return (EINVAL); 2218 name = namebuf; 2219 if (namelen > sizeof(namebuf)) 2220 name = malloc(namelen, M_SYSCTL, M_WAITOK); 2221 error = copyin(oname, name, namelen); 2222 if (error != 0) 2223 goto out; 2224 2225 oid[0] = CTL_SYSCTL; 2226 oid[1] = CTL_SYSCTL_NAME2OID; 2227 oidlen = sizeof(oid); 2228 error = kernel_sysctl(td, oid, 2, oid, &oidlen, (void *)name, namelen, 2229 retval, flags); 2230 if (error != 0) 2231 goto out; 2232 error = userland_sysctl(td, oid, *retval / sizeof(int), old, oldlenp, 2233 inkernel, new, newlen, retval, flags); 2234 2235 out: 2236 if (namelen > sizeof(namebuf)) 2237 free(name, M_SYSCTL); 2238 return (error); 2239 } 2240 2241 #ifndef _SYS_SYSPROTO_H_ 2242 struct __sysctlbyname_args { 2243 const char *name; 2244 size_t namelen; 2245 void *old; 2246 size_t *oldlenp; 2247 void *new; 2248 size_t newlen; 2249 }; 2250 #endif 2251 int 2252 sys___sysctlbyname(struct thread *td, struct __sysctlbyname_args *uap) 2253 { 2254 size_t rv; 2255 int error; 2256 2257 error = kern___sysctlbyname(td, uap->name, uap->namelen, uap->old, 2258 uap->oldlenp, uap->new, uap->newlen, &rv, 0, 0); 2259 if (error != 0) 2260 return (error); 2261 if (uap->oldlenp != NULL) 2262 error = copyout(&rv, uap->oldlenp, sizeof(rv)); 2263 2264 return (error); 2265 } 2266 2267 /* 2268 * This is used from various compatibility syscalls too. That's why name 2269 * must be in kernel space. 2270 */ 2271 int 2272 userland_sysctl(struct thread *td, int *name, u_int namelen, void *old, 2273 size_t *oldlenp, int inkernel, const void *new, size_t newlen, 2274 size_t *retval, int flags) 2275 { 2276 int error = 0, memlocked; 2277 struct sysctl_req req; 2278 2279 bzero(&req, sizeof req); 2280 2281 req.td = td; 2282 req.flags = flags; 2283 2284 if (oldlenp) { 2285 if (inkernel) { 2286 req.oldlen = *oldlenp; 2287 } else { 2288 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 2289 if (error) 2290 return (error); 2291 } 2292 } 2293 req.validlen = req.oldlen; 2294 req.oldptr = old; 2295 2296 if (new != NULL) { 2297 req.newlen = newlen; 2298 req.newptr = new; 2299 } 2300 2301 req.oldfunc = sysctl_old_user; 2302 req.newfunc = sysctl_new_user; 2303 req.lock = REQ_UNWIRED; 2304 2305 #ifdef KTRACE 2306 if (KTRPOINT(curthread, KTR_SYSCTL)) 2307 ktrsysctl(name, namelen); 2308 #endif 2309 memlocked = 0; 2310 if (req.oldptr && req.oldlen > 4 * PAGE_SIZE) { 2311 memlocked = 1; 2312 sx_xlock(&sysctlmemlock); 2313 } 2314 CURVNET_SET(TD_TO_VNET(td)); 2315 2316 for (;;) { 2317 req.oldidx = 0; 2318 req.newidx = 0; 2319 error = sysctl_root(0, name, namelen, &req); 2320 if (error != EAGAIN) 2321 break; 2322 kern_yield(PRI_USER); 2323 } 2324 2325 CURVNET_RESTORE(); 2326 2327 if (req.lock == REQ_WIRED && req.validlen > 0) 2328 vsunlock(req.oldptr, req.validlen); 2329 if (memlocked) 2330 sx_xunlock(&sysctlmemlock); 2331 2332 if (error && error != ENOMEM) 2333 return (error); 2334 2335 if (retval) { 2336 if (req.oldptr && req.oldidx > req.validlen) 2337 *retval = req.validlen; 2338 else 2339 *retval = req.oldidx; 2340 } 2341 return (error); 2342 } 2343 2344 /* 2345 * Drain into a sysctl struct. The user buffer should be wired if a page 2346 * fault would cause issue. 2347 */ 2348 static int 2349 sbuf_sysctl_drain(void *arg, const char *data, int len) 2350 { 2351 struct sysctl_req *req = arg; 2352 int error; 2353 2354 error = SYSCTL_OUT(req, data, len); 2355 KASSERT(error >= 0, ("Got unexpected negative value %d", error)); 2356 return (error == 0 ? len : -error); 2357 } 2358 2359 struct sbuf * 2360 sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, 2361 struct sysctl_req *req) 2362 { 2363 2364 /* Supply a default buffer size if none given. */ 2365 if (buf == NULL && length == 0) 2366 length = 64; 2367 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL); 2368 sbuf_set_drain(s, sbuf_sysctl_drain, req); 2369 return (s); 2370 } 2371 2372 #ifdef DDB 2373 2374 /* The current OID the debugger is working with */ 2375 static struct sysctl_oid *g_ddb_oid; 2376 2377 /* The current flags specified by the user */ 2378 static int g_ddb_sysctl_flags; 2379 2380 /* Check to see if the last sysctl printed */ 2381 static int g_ddb_sysctl_printed; 2382 2383 static const int ctl_sign[CTLTYPE+1] = { 2384 [CTLTYPE_INT] = 1, 2385 [CTLTYPE_LONG] = 1, 2386 [CTLTYPE_S8] = 1, 2387 [CTLTYPE_S16] = 1, 2388 [CTLTYPE_S32] = 1, 2389 [CTLTYPE_S64] = 1, 2390 }; 2391 2392 static const int ctl_size[CTLTYPE+1] = { 2393 [CTLTYPE_INT] = sizeof(int), 2394 [CTLTYPE_UINT] = sizeof(u_int), 2395 [CTLTYPE_LONG] = sizeof(long), 2396 [CTLTYPE_ULONG] = sizeof(u_long), 2397 [CTLTYPE_S8] = sizeof(int8_t), 2398 [CTLTYPE_S16] = sizeof(int16_t), 2399 [CTLTYPE_S32] = sizeof(int32_t), 2400 [CTLTYPE_S64] = sizeof(int64_t), 2401 [CTLTYPE_U8] = sizeof(uint8_t), 2402 [CTLTYPE_U16] = sizeof(uint16_t), 2403 [CTLTYPE_U32] = sizeof(uint32_t), 2404 [CTLTYPE_U64] = sizeof(uint64_t), 2405 }; 2406 2407 #define DB_SYSCTL_NAME_ONLY 0x001 /* Compare with -N */ 2408 #define DB_SYSCTL_VALUE_ONLY 0x002 /* Compare with -n */ 2409 #define DB_SYSCTL_OPAQUE 0x004 /* Compare with -o */ 2410 #define DB_SYSCTL_HEX 0x008 /* Compare with -x */ 2411 2412 #define DB_SYSCTL_SAFE_ONLY 0x100 /* Only simple types */ 2413 2414 static const char db_sysctl_modifs[] = { 2415 'N', 'n', 'o', 'x', 2416 }; 2417 2418 static const int db_sysctl_modif_values[] = { 2419 DB_SYSCTL_NAME_ONLY, DB_SYSCTL_VALUE_ONLY, 2420 DB_SYSCTL_OPAQUE, DB_SYSCTL_HEX, 2421 }; 2422 2423 /* Handlers considered safe to print while recursing */ 2424 static int (* const db_safe_handlers[])(SYSCTL_HANDLER_ARGS) = { 2425 sysctl_handle_bool, 2426 sysctl_handle_8, 2427 sysctl_handle_16, 2428 sysctl_handle_32, 2429 sysctl_handle_64, 2430 sysctl_handle_int, 2431 sysctl_handle_long, 2432 sysctl_handle_string, 2433 sysctl_handle_opaque, 2434 }; 2435 2436 /* 2437 * Use in place of sysctl_old_kernel to print sysctl values. 2438 * 2439 * Compare to the output handling in show_var from sbin/sysctl/sysctl.c 2440 */ 2441 static int 2442 sysctl_old_ddb(struct sysctl_req *req, const void *ptr, size_t len) 2443 { 2444 const u_char *val, *p; 2445 const char *sep1; 2446 size_t intlen, slen; 2447 uintmax_t umv; 2448 intmax_t mv; 2449 int sign, ctltype, hexlen, xflag, error; 2450 2451 /* Suppress false-positive GCC uninitialized variable warnings */ 2452 mv = 0; 2453 umv = 0; 2454 2455 slen = len; 2456 val = p = ptr; 2457 2458 if (ptr == NULL) { 2459 error = 0; 2460 goto out; 2461 } 2462 2463 /* We are going to print */ 2464 g_ddb_sysctl_printed = 1; 2465 2466 xflag = g_ddb_sysctl_flags & DB_SYSCTL_HEX; 2467 2468 ctltype = (g_ddb_oid->oid_kind & CTLTYPE); 2469 sign = ctl_sign[ctltype]; 2470 intlen = ctl_size[ctltype]; 2471 2472 switch (ctltype) { 2473 case CTLTYPE_NODE: 2474 case CTLTYPE_STRING: 2475 db_printf("%.*s", (int) len, (const char *) p); 2476 error = 0; 2477 goto out; 2478 2479 case CTLTYPE_INT: 2480 case CTLTYPE_UINT: 2481 case CTLTYPE_LONG: 2482 case CTLTYPE_ULONG: 2483 case CTLTYPE_S8: 2484 case CTLTYPE_S16: 2485 case CTLTYPE_S32: 2486 case CTLTYPE_S64: 2487 case CTLTYPE_U8: 2488 case CTLTYPE_U16: 2489 case CTLTYPE_U32: 2490 case CTLTYPE_U64: 2491 hexlen = 2 + (intlen * CHAR_BIT + 3) / 4; 2492 sep1 = ""; 2493 while (len >= intlen) { 2494 switch (ctltype) { 2495 case CTLTYPE_INT: 2496 case CTLTYPE_UINT: 2497 umv = *(const u_int *)p; 2498 mv = *(const int *)p; 2499 break; 2500 case CTLTYPE_LONG: 2501 case CTLTYPE_ULONG: 2502 umv = *(const u_long *)p; 2503 mv = *(const long *)p; 2504 break; 2505 case CTLTYPE_S8: 2506 case CTLTYPE_U8: 2507 umv = *(const uint8_t *)p; 2508 mv = *(const int8_t *)p; 2509 break; 2510 case CTLTYPE_S16: 2511 case CTLTYPE_U16: 2512 umv = *(const uint16_t *)p; 2513 mv = *(const int16_t *)p; 2514 break; 2515 case CTLTYPE_S32: 2516 case CTLTYPE_U32: 2517 umv = *(const uint32_t *)p; 2518 mv = *(const int32_t *)p; 2519 break; 2520 case CTLTYPE_S64: 2521 case CTLTYPE_U64: 2522 umv = *(const uint64_t *)p; 2523 mv = *(const int64_t *)p; 2524 break; 2525 } 2526 2527 db_printf("%s", sep1); 2528 if (xflag) 2529 db_printf("%#0*jx", hexlen, umv); 2530 else if (!sign) 2531 db_printf("%ju", umv); 2532 else if (g_ddb_oid->oid_fmt[1] == 'K') { 2533 /* Kelvins are currently unsupported. */ 2534 error = EOPNOTSUPP; 2535 goto out; 2536 } else 2537 db_printf("%jd", mv); 2538 2539 sep1 = " "; 2540 len -= intlen; 2541 p += intlen; 2542 } 2543 error = 0; 2544 goto out; 2545 2546 case CTLTYPE_OPAQUE: 2547 /* TODO: Support struct functions. */ 2548 2549 /* FALLTHROUGH */ 2550 default: 2551 db_printf("Format:%s Length:%zu Dump:0x", 2552 g_ddb_oid->oid_fmt, len); 2553 while (len-- && (xflag || p < val + 16)) 2554 db_printf("%02x", *p++); 2555 if (!xflag && len > 16) 2556 db_printf("..."); 2557 error = 0; 2558 goto out; 2559 } 2560 2561 out: 2562 req->oldidx += slen; 2563 return (error); 2564 } 2565 2566 /* 2567 * Avoid setting new sysctl values from the debugger 2568 */ 2569 static int 2570 sysctl_new_ddb(struct sysctl_req *req, void *p, size_t l) 2571 { 2572 2573 if (!req->newptr) 2574 return (0); 2575 2576 /* Changing sysctls from the debugger is currently unsupported */ 2577 return (EPERM); 2578 } 2579 2580 /* 2581 * Run a sysctl handler with the DDB oldfunc and newfunc attached. 2582 * Instead of copying any output to a buffer we'll dump it right to 2583 * the console. 2584 */ 2585 static int 2586 db_sysctl(struct sysctl_oid *oidp, int *name, u_int namelen, 2587 void *old, size_t *oldlenp, size_t *retval, int flags) 2588 { 2589 struct sysctl_req req; 2590 int error; 2591 2592 /* Setup the request */ 2593 bzero(&req, sizeof req); 2594 req.td = kdb_thread; 2595 req.oldfunc = sysctl_old_ddb; 2596 req.newfunc = sysctl_new_ddb; 2597 req.lock = REQ_UNWIRED; 2598 if (oldlenp) { 2599 req.oldlen = *oldlenp; 2600 } 2601 req.validlen = req.oldlen; 2602 if (old) { 2603 req.oldptr = old; 2604 } 2605 2606 /* Setup our globals for sysctl_old_ddb */ 2607 g_ddb_oid = oidp; 2608 g_ddb_sysctl_flags = flags; 2609 g_ddb_sysctl_printed = 0; 2610 2611 error = sysctl_root(0, name, namelen, &req); 2612 2613 /* Reset globals */ 2614 g_ddb_oid = NULL; 2615 g_ddb_sysctl_flags = 0; 2616 2617 if (retval) { 2618 if (req.oldptr && req.oldidx > req.validlen) 2619 *retval = req.validlen; 2620 else 2621 *retval = req.oldidx; 2622 } 2623 return (error); 2624 } 2625 2626 /* 2627 * Show a sysctl's name 2628 */ 2629 static void 2630 db_show_oid_name(int *oid, size_t nlen) 2631 { 2632 struct sysctl_oid *oidp; 2633 int qoid[CTL_MAXNAME+2]; 2634 int error; 2635 2636 qoid[0] = 0; 2637 memcpy(qoid + 2, oid, nlen * sizeof(int)); 2638 qoid[1] = 1; 2639 2640 error = sysctl_find_oid(qoid, nlen + 2, &oidp, NULL, NULL); 2641 if (error) 2642 db_error("sysctl name oid"); 2643 2644 error = db_sysctl(oidp, qoid, nlen + 2, NULL, NULL, NULL, 0); 2645 if (error) 2646 db_error("sysctl name"); 2647 } 2648 2649 /* 2650 * Check to see if an OID is safe to print from ddb. 2651 */ 2652 static bool 2653 db_oid_safe(const struct sysctl_oid *oidp) 2654 { 2655 for (unsigned int i = 0; i < nitems(db_safe_handlers); ++i) { 2656 if (oidp->oid_handler == db_safe_handlers[i]) 2657 return (true); 2658 } 2659 2660 return (false); 2661 } 2662 2663 /* 2664 * Show a sysctl at a specific OID 2665 * Compare to the input handling in show_var from sbin/sysctl/sysctl.c 2666 */ 2667 static int 2668 db_show_oid(struct sysctl_oid *oidp, int *oid, size_t nlen, int flags) 2669 { 2670 int error, xflag, oflag, Nflag, nflag; 2671 size_t len; 2672 2673 xflag = flags & DB_SYSCTL_HEX; 2674 oflag = flags & DB_SYSCTL_OPAQUE; 2675 nflag = flags & DB_SYSCTL_VALUE_ONLY; 2676 Nflag = flags & DB_SYSCTL_NAME_ONLY; 2677 2678 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_OPAQUE && 2679 (!xflag && !oflag)) 2680 return (0); 2681 2682 if (Nflag) { 2683 db_show_oid_name(oid, nlen); 2684 error = 0; 2685 goto out; 2686 } 2687 2688 if (!nflag) { 2689 db_show_oid_name(oid, nlen); 2690 db_printf(": "); 2691 } 2692 2693 if ((flags & DB_SYSCTL_SAFE_ONLY) && !db_oid_safe(oidp)) { 2694 db_printf("Skipping, unsafe to print while recursing."); 2695 error = 0; 2696 goto out; 2697 } 2698 2699 /* Try once, and ask about the size */ 2700 len = 0; 2701 error = db_sysctl(oidp, oid, nlen, 2702 NULL, NULL, &len, flags); 2703 if (error) 2704 goto out; 2705 2706 if (!g_ddb_sysctl_printed) 2707 /* Lie about the size */ 2708 error = db_sysctl(oidp, oid, nlen, 2709 (void *) 1, &len, NULL, flags); 2710 2711 out: 2712 db_printf("\n"); 2713 return (error); 2714 } 2715 2716 /* 2717 * Show all sysctls under a specific OID 2718 * Compare to sysctl_all from sbin/sysctl/sysctl.c 2719 */ 2720 static int 2721 db_show_sysctl_all(int *oid, size_t len, int flags) 2722 { 2723 struct sysctl_oid *oidp; 2724 int name1[CTL_MAXNAME + 2], name2[CTL_MAXNAME + 2]; 2725 size_t l1, l2; 2726 2727 name1[0] = CTL_SYSCTL; 2728 name1[1] = CTL_SYSCTL_NEXT; 2729 l1 = 2; 2730 if (len) { 2731 memcpy(name1+2, oid, len * sizeof(int)); 2732 l1 +=len; 2733 } else { 2734 name1[2] = 1; 2735 l1++; 2736 } 2737 for (;;) { 2738 int i, error; 2739 2740 l2 = sizeof(name2); 2741 error = kernel_sysctl(kdb_thread, name1, l1, 2742 name2, &l2, NULL, 0, &l2, 0); 2743 if (error != 0) { 2744 if (error == ENOENT) 2745 return (0); 2746 else 2747 db_error("sysctl(getnext)"); 2748 } 2749 2750 l2 /= sizeof(int); 2751 2752 if (l2 < (unsigned int)len) 2753 return (0); 2754 2755 for (i = 0; i < len; i++) 2756 if (name2[i] != oid[i]) 2757 return (0); 2758 2759 /* Find the OID in question */ 2760 error = sysctl_find_oid(name2, l2, &oidp, NULL, NULL); 2761 if (error) 2762 return (error); 2763 2764 i = db_show_oid(oidp, name2, l2, flags | DB_SYSCTL_SAFE_ONLY); 2765 2766 if (db_pager_quit) 2767 return (0); 2768 2769 memcpy(name1+2, name2, l2 * sizeof(int)); 2770 l1 = 2 + l2; 2771 } 2772 } 2773 2774 /* 2775 * Show a sysctl by its user facing string 2776 */ 2777 static int 2778 db_sysctlbyname(char *name, int flags) 2779 { 2780 struct sysctl_oid *oidp; 2781 int oid[CTL_MAXNAME]; 2782 int error, nlen; 2783 2784 error = name2oid(name, oid, &nlen, &oidp); 2785 if (error) { 2786 return (error); 2787 } 2788 2789 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2790 db_show_sysctl_all(oid, nlen, flags); 2791 } else { 2792 error = db_show_oid(oidp, oid, nlen, flags); 2793 } 2794 2795 return (error); 2796 } 2797 2798 static void 2799 db_sysctl_cmd_usage(void) 2800 { 2801 db_printf( 2802 " sysctl [/Nnox] <sysctl> \n" 2803 " \n" 2804 " <sysctl> The name of the sysctl to show. \n" 2805 " \n" 2806 " Show a sysctl by hooking into SYSCTL_IN and SYSCTL_OUT. \n" 2807 " This will work for most sysctls, but should not be used \n" 2808 " with sysctls that are known to malloc. \n" 2809 " \n" 2810 " While recursing any \"unsafe\" sysctls will be skipped. \n" 2811 " Call sysctl directly on the sysctl to try printing the \n" 2812 " skipped sysctl. This is unsafe and may make the ddb \n" 2813 " session unusable. \n" 2814 " \n" 2815 " Arguments: \n" 2816 " /N Display only the name of the sysctl. \n" 2817 " /n Display only the value of the sysctl. \n" 2818 " /o Display opaque values. \n" 2819 " /x Display the sysctl in hex. \n" 2820 " \n" 2821 "For example: \n" 2822 "sysctl vm.v_free_min \n" 2823 "vn.v_free_min: 12669 \n" 2824 ); 2825 } 2826 2827 /* 2828 * Show a specific sysctl similar to sysctl (8). 2829 */ 2830 DB_FUNC(sysctl, db_sysctl_cmd, db_cmd_table, CS_OWN, NULL) 2831 { 2832 char name[TOK_STRING_SIZE]; 2833 int error, i, t, flags; 2834 2835 /* Parse the modifiers */ 2836 t = db_read_token(); 2837 if (t == tSLASH || t == tMINUS) { 2838 t = db_read_token(); 2839 if (t != tIDENT) { 2840 db_printf("Bad modifier\n"); 2841 error = EINVAL; 2842 goto out; 2843 } 2844 db_strcpy(modif, db_tok_string); 2845 } 2846 else { 2847 db_unread_token(t); 2848 modif[0] = '\0'; 2849 } 2850 2851 flags = 0; 2852 for (i = 0; i < nitems(db_sysctl_modifs); i++) { 2853 if (strchr(modif, db_sysctl_modifs[i])) { 2854 flags |= db_sysctl_modif_values[i]; 2855 } 2856 } 2857 2858 /* Parse the sysctl names */ 2859 t = db_read_token(); 2860 if (t != tIDENT) { 2861 db_printf("Need sysctl name\n"); 2862 error = EINVAL; 2863 goto out; 2864 } 2865 2866 /* Copy the name into a temporary buffer */ 2867 db_strcpy(name, db_tok_string); 2868 2869 /* Ensure there is no trailing cruft */ 2870 t = db_read_token(); 2871 if (t != tEOL) { 2872 db_printf("Unexpected sysctl argument\n"); 2873 error = EINVAL; 2874 goto out; 2875 } 2876 2877 error = db_sysctlbyname(name, flags); 2878 if (error == ENOENT) { 2879 db_printf("unknown oid: '%s'\n", db_tok_string); 2880 goto out; 2881 } else if (error) { 2882 db_printf("%s: error: %d\n", db_tok_string, error); 2883 goto out; 2884 } 2885 2886 out: 2887 /* Ensure we eat all of our text */ 2888 db_flush_lex(); 2889 2890 if (error == EINVAL) { 2891 db_sysctl_cmd_usage(); 2892 } 2893 } 2894 2895 #endif /* DDB */ 2896