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