1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Mike Karels at Berkeley Software Design, Inc. 9 * 10 * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD 11 * project, to make these variables more userfriendly. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94 38 */ 39 40 #include <sys/cdefs.h> 41 __FBSDID("$FreeBSD$"); 42 43 #include "opt_capsicum.h" 44 #include "opt_ddb.h" 45 #include "opt_ktrace.h" 46 #include "opt_sysctl.h" 47 48 #include <sys/param.h> 49 #include <sys/fail.h> 50 #include <sys/systm.h> 51 #include <sys/capsicum.h> 52 #include <sys/kernel.h> 53 #include <sys/limits.h> 54 #include <sys/sysctl.h> 55 #include <sys/malloc.h> 56 #include <sys/priv.h> 57 #include <sys/proc.h> 58 #include <sys/jail.h> 59 #include <sys/kdb.h> 60 #include <sys/lock.h> 61 #include <sys/mutex.h> 62 #include <sys/rmlock.h> 63 #include <sys/sbuf.h> 64 #include <sys/sx.h> 65 #include <sys/sysproto.h> 66 #include <sys/uio.h> 67 #ifdef KTRACE 68 #include <sys/ktrace.h> 69 #endif 70 71 #ifdef DDB 72 #include <ddb/ddb.h> 73 #include <ddb/db_lex.h> 74 #endif 75 76 #include <net/vnet.h> 77 78 #include <security/mac/mac_framework.h> 79 80 #include <vm/vm.h> 81 #include <vm/vm_extern.h> 82 83 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic"); 84 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids"); 85 static MALLOC_DEFINE(M_SYSCTLTMP, "sysctltmp", "sysctl temp output buffer"); 86 87 /* 88 * The sysctllock protects the MIB tree. It also protects sysctl 89 * contexts used with dynamic sysctls. The sysctl_register_oid() and 90 * sysctl_unregister_oid() routines require the sysctllock to already 91 * be held, so the sysctl_wlock() and sysctl_wunlock() routines are 92 * provided for the few places in the kernel which need to use that 93 * API rather than using the dynamic API. Use of the dynamic API is 94 * strongly encouraged for most code. 95 * 96 * The sysctlmemlock is used to limit the amount of user memory wired for 97 * sysctl requests. This is implemented by serializing any userland 98 * sysctl requests larger than a single page via an exclusive lock. 99 * 100 * The sysctlstringlock is used to protect concurrent access to writable 101 * string nodes in sysctl_handle_string(). 102 */ 103 static struct rmlock sysctllock; 104 static struct sx __exclusive_cache_line sysctlmemlock; 105 static struct sx sysctlstringlock; 106 107 #define SYSCTL_WLOCK() rm_wlock(&sysctllock) 108 #define SYSCTL_WUNLOCK() rm_wunlock(&sysctllock) 109 #define SYSCTL_RLOCK(tracker) rm_rlock(&sysctllock, (tracker)) 110 #define SYSCTL_RUNLOCK(tracker) rm_runlock(&sysctllock, (tracker)) 111 #define SYSCTL_WLOCKED() rm_wowned(&sysctllock) 112 #define SYSCTL_ASSERT_LOCKED() rm_assert(&sysctllock, RA_LOCKED) 113 #define SYSCTL_ASSERT_WLOCKED() rm_assert(&sysctllock, RA_WLOCKED) 114 #define SYSCTL_ASSERT_RLOCKED() rm_assert(&sysctllock, RA_RLOCKED) 115 #define SYSCTL_INIT() rm_init_flags(&sysctllock, "sysctl lock", \ 116 RM_SLEEPABLE) 117 #define SYSCTL_SLEEP(ch, wmesg, timo) \ 118 rm_sleep(ch, &sysctllock, 0, wmesg, timo) 119 120 static int sysctl_root(SYSCTL_HANDLER_ARGS); 121 122 /* Root list */ 123 struct sysctl_oid_list sysctl__children = SLIST_HEAD_INITIALIZER(&sysctl__children); 124 125 static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, 126 int recurse); 127 static int sysctl_old_kernel(struct sysctl_req *, const void *, size_t); 128 static int sysctl_new_kernel(struct sysctl_req *, void *, size_t); 129 130 static struct sysctl_oid * 131 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list) 132 { 133 struct sysctl_oid *oidp; 134 135 SYSCTL_ASSERT_LOCKED(); 136 SLIST_FOREACH(oidp, list, oid_link) { 137 if (strcmp(oidp->oid_name, name) == 0) { 138 return (oidp); 139 } 140 } 141 return (NULL); 142 } 143 144 /* 145 * Initialization of the MIB tree. 146 * 147 * Order by number in each list. 148 */ 149 void 150 sysctl_wlock(void) 151 { 152 153 SYSCTL_WLOCK(); 154 } 155 156 void 157 sysctl_wunlock(void) 158 { 159 160 SYSCTL_WUNLOCK(); 161 } 162 163 static int 164 sysctl_root_handler_locked(struct sysctl_oid *oid, void *arg1, intmax_t arg2, 165 struct sysctl_req *req, struct rm_priotracker *tracker) 166 { 167 int error; 168 169 if (oid->oid_kind & CTLFLAG_DYN) 170 atomic_add_int(&oid->oid_running, 1); 171 172 if (tracker != NULL) 173 SYSCTL_RUNLOCK(tracker); 174 else 175 SYSCTL_WUNLOCK(); 176 177 /* 178 * Treat set CTLFLAG_NEEDGIANT and unset CTLFLAG_MPSAFE flags the same, 179 * untill we're ready to remove all traces of Giant from sysctl(9). 180 */ 181 if ((oid->oid_kind & CTLFLAG_NEEDGIANT) || 182 (!(oid->oid_kind & CTLFLAG_MPSAFE))) 183 mtx_lock(&Giant); 184 error = oid->oid_handler(oid, arg1, arg2, req); 185 if ((oid->oid_kind & CTLFLAG_NEEDGIANT) || 186 (!(oid->oid_kind & CTLFLAG_MPSAFE))) 187 mtx_unlock(&Giant); 188 189 KFAIL_POINT_ERROR(_debug_fail_point, sysctl_running, error); 190 191 if (tracker != NULL) 192 SYSCTL_RLOCK(tracker); 193 else 194 SYSCTL_WLOCK(); 195 196 if (oid->oid_kind & CTLFLAG_DYN) { 197 if (atomic_fetchadd_int(&oid->oid_running, -1) == 1 && 198 (oid->oid_kind & CTLFLAG_DYING) != 0) 199 wakeup(&oid->oid_running); 200 } 201 202 return (error); 203 } 204 205 static void 206 sysctl_load_tunable_by_oid_locked(struct sysctl_oid *oidp) 207 { 208 struct sysctl_req req; 209 struct sysctl_oid *curr; 210 char *penv = NULL; 211 char path[96]; 212 ssize_t rem = sizeof(path); 213 ssize_t len; 214 uint8_t data[512] __aligned(sizeof(uint64_t)); 215 int size; 216 int error; 217 218 path[--rem] = 0; 219 220 for (curr = oidp; curr != NULL; curr = SYSCTL_PARENT(curr)) { 221 len = strlen(curr->oid_name); 222 rem -= len; 223 if (curr != oidp) 224 rem -= 1; 225 if (rem < 0) { 226 printf("OID path exceeds %d bytes\n", (int)sizeof(path)); 227 return; 228 } 229 memcpy(path + rem, curr->oid_name, len); 230 if (curr != oidp) 231 path[rem + len] = '.'; 232 } 233 234 memset(&req, 0, sizeof(req)); 235 236 req.td = curthread; 237 req.oldfunc = sysctl_old_kernel; 238 req.newfunc = sysctl_new_kernel; 239 req.lock = REQ_UNWIRED; 240 241 switch (oidp->oid_kind & CTLTYPE) { 242 case CTLTYPE_INT: 243 if (getenv_array(path + rem, data, sizeof(data), &size, 244 sizeof(int), GETENV_SIGNED) == 0) 245 return; 246 req.newlen = size; 247 req.newptr = data; 248 break; 249 case CTLTYPE_UINT: 250 if (getenv_array(path + rem, data, sizeof(data), &size, 251 sizeof(int), GETENV_UNSIGNED) == 0) 252 return; 253 req.newlen = size; 254 req.newptr = data; 255 break; 256 case CTLTYPE_LONG: 257 if (getenv_array(path + rem, data, sizeof(data), &size, 258 sizeof(long), GETENV_SIGNED) == 0) 259 return; 260 req.newlen = size; 261 req.newptr = data; 262 break; 263 case CTLTYPE_ULONG: 264 if (getenv_array(path + rem, data, sizeof(data), &size, 265 sizeof(long), GETENV_UNSIGNED) == 0) 266 return; 267 req.newlen = size; 268 req.newptr = data; 269 break; 270 case CTLTYPE_S8: 271 if (getenv_array(path + rem, data, sizeof(data), &size, 272 sizeof(int8_t), GETENV_SIGNED) == 0) 273 return; 274 req.newlen = size; 275 req.newptr = data; 276 break; 277 case CTLTYPE_S16: 278 if (getenv_array(path + rem, data, sizeof(data), &size, 279 sizeof(int16_t), GETENV_SIGNED) == 0) 280 return; 281 req.newlen = size; 282 req.newptr = data; 283 break; 284 case CTLTYPE_S32: 285 if (getenv_array(path + rem, data, sizeof(data), &size, 286 sizeof(int32_t), GETENV_SIGNED) == 0) 287 return; 288 req.newlen = size; 289 req.newptr = data; 290 break; 291 case CTLTYPE_S64: 292 if (getenv_array(path + rem, data, sizeof(data), &size, 293 sizeof(int64_t), GETENV_SIGNED) == 0) 294 return; 295 req.newlen = size; 296 req.newptr = data; 297 break; 298 case CTLTYPE_U8: 299 if (getenv_array(path + rem, data, sizeof(data), &size, 300 sizeof(uint8_t), GETENV_UNSIGNED) == 0) 301 return; 302 req.newlen = size; 303 req.newptr = data; 304 break; 305 case CTLTYPE_U16: 306 if (getenv_array(path + rem, data, sizeof(data), &size, 307 sizeof(uint16_t), GETENV_UNSIGNED) == 0) 308 return; 309 req.newlen = size; 310 req.newptr = data; 311 break; 312 case CTLTYPE_U32: 313 if (getenv_array(path + rem, data, sizeof(data), &size, 314 sizeof(uint32_t), GETENV_UNSIGNED) == 0) 315 return; 316 req.newlen = size; 317 req.newptr = data; 318 break; 319 case CTLTYPE_U64: 320 if (getenv_array(path + rem, data, sizeof(data), &size, 321 sizeof(uint64_t), GETENV_UNSIGNED) == 0) 322 return; 323 req.newlen = size; 324 req.newptr = data; 325 break; 326 case CTLTYPE_STRING: 327 penv = kern_getenv(path + rem); 328 if (penv == NULL) 329 return; 330 req.newlen = strlen(penv); 331 req.newptr = penv; 332 break; 333 default: 334 return; 335 } 336 error = sysctl_root_handler_locked(oidp, oidp->oid_arg1, 337 oidp->oid_arg2, &req, NULL); 338 if (error != 0) 339 printf("Setting sysctl %s failed: %d\n", path + rem, error); 340 if (penv != NULL) 341 freeenv(penv); 342 } 343 344 /* 345 * Locate the path to a given oid. Returns the length of the resulting path, 346 * or -1 if the oid was not found. nodes must have room for CTL_MAXNAME 347 * elements and be NULL initialized. 348 */ 349 static int 350 sysctl_search_oid(struct sysctl_oid **nodes, struct sysctl_oid *needle) 351 { 352 int indx; 353 354 SYSCTL_ASSERT_LOCKED(); 355 indx = 0; 356 while (indx < CTL_MAXNAME && indx >= 0) { 357 if (nodes[indx] == NULL && indx == 0) 358 nodes[indx] = SLIST_FIRST(&sysctl__children); 359 else if (nodes[indx] == NULL) 360 nodes[indx] = SLIST_FIRST(&nodes[indx - 1]->oid_children); 361 else 362 nodes[indx] = SLIST_NEXT(nodes[indx], oid_link); 363 364 if (nodes[indx] == needle) 365 return (indx + 1); 366 367 if (nodes[indx] == NULL) { 368 indx--; 369 continue; 370 } 371 372 if ((nodes[indx]->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 373 indx++; 374 continue; 375 } 376 } 377 return (-1); 378 } 379 380 static void 381 sysctl_warn_reuse(const char *func, struct sysctl_oid *leaf) 382 { 383 struct sysctl_oid *nodes[CTL_MAXNAME]; 384 char buf[128]; 385 struct sbuf sb; 386 int rc, i; 387 388 (void)sbuf_new(&sb, buf, sizeof(buf), SBUF_FIXEDLEN | SBUF_INCLUDENUL); 389 sbuf_set_drain(&sb, sbuf_printf_drain, NULL); 390 391 sbuf_printf(&sb, "%s: can't re-use a leaf (", __func__); 392 393 memset(nodes, 0, sizeof(nodes)); 394 rc = sysctl_search_oid(nodes, leaf); 395 if (rc > 0) { 396 for (i = 0; i < rc; i++) 397 sbuf_printf(&sb, "%s%.*s", nodes[i]->oid_name, 398 i != (rc - 1), "."); 399 } else { 400 sbuf_printf(&sb, "%s", leaf->oid_name); 401 } 402 sbuf_printf(&sb, ")!\n"); 403 404 (void)sbuf_finish(&sb); 405 } 406 407 #ifdef SYSCTL_DEBUG 408 static int 409 sysctl_reuse_test(SYSCTL_HANDLER_ARGS) 410 { 411 struct rm_priotracker tracker; 412 413 SYSCTL_RLOCK(&tracker); 414 sysctl_warn_reuse(__func__, oidp); 415 SYSCTL_RUNLOCK(&tracker); 416 return (0); 417 } 418 SYSCTL_PROC(_sysctl, OID_AUTO, reuse_test, 419 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE, 0, 0, sysctl_reuse_test, "-", 420 ""); 421 #endif 422 423 void 424 sysctl_register_oid(struct sysctl_oid *oidp) 425 { 426 struct sysctl_oid_list *parent = oidp->oid_parent; 427 struct sysctl_oid *p; 428 struct sysctl_oid *q; 429 int oid_number; 430 int timeout = 2; 431 432 /* 433 * First check if another oid with the same name already 434 * exists in the parent's list. 435 */ 436 SYSCTL_ASSERT_WLOCKED(); 437 p = sysctl_find_oidname(oidp->oid_name, parent); 438 if (p != NULL) { 439 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 440 p->oid_refcnt++; 441 return; 442 } else { 443 sysctl_warn_reuse(__func__, p); 444 return; 445 } 446 } 447 /* get current OID number */ 448 oid_number = oidp->oid_number; 449 450 #if (OID_AUTO >= 0) 451 #error "OID_AUTO is expected to be a negative value" 452 #endif 453 /* 454 * Any negative OID number qualifies as OID_AUTO. Valid OID 455 * numbers should always be positive. 456 * 457 * NOTE: DO NOT change the starting value here, change it in 458 * <sys/sysctl.h>, and make sure it is at least 256 to 459 * accommodate e.g. net.inet.raw as a static sysctl node. 460 */ 461 if (oid_number < 0) { 462 static int newoid; 463 464 /* 465 * By decrementing the next OID number we spend less 466 * time inserting the OIDs into a sorted list. 467 */ 468 if (--newoid < CTL_AUTO_START) 469 newoid = 0x7fffffff; 470 471 oid_number = newoid; 472 } 473 474 /* 475 * Insert the OID into the parent's list sorted by OID number. 476 */ 477 retry: 478 q = NULL; 479 SLIST_FOREACH(p, parent, oid_link) { 480 /* check if the current OID number is in use */ 481 if (oid_number == p->oid_number) { 482 /* get the next valid OID number */ 483 if (oid_number < CTL_AUTO_START || 484 oid_number == 0x7fffffff) { 485 /* wraparound - restart */ 486 oid_number = CTL_AUTO_START; 487 /* don't loop forever */ 488 if (!timeout--) 489 panic("sysctl: Out of OID numbers\n"); 490 goto retry; 491 } else { 492 oid_number++; 493 } 494 } else if (oid_number < p->oid_number) 495 break; 496 q = p; 497 } 498 /* check for non-auto OID number collision */ 499 if (oidp->oid_number >= 0 && oidp->oid_number < CTL_AUTO_START && 500 oid_number >= CTL_AUTO_START) { 501 printf("sysctl: OID number(%d) is already in use for '%s'\n", 502 oidp->oid_number, oidp->oid_name); 503 } 504 /* update the OID number, if any */ 505 oidp->oid_number = oid_number; 506 if (q != NULL) 507 SLIST_INSERT_AFTER(q, oidp, oid_link); 508 else 509 SLIST_INSERT_HEAD(parent, oidp, oid_link); 510 511 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE && 512 #ifdef VIMAGE 513 (oidp->oid_kind & CTLFLAG_VNET) == 0 && 514 #endif 515 (oidp->oid_kind & CTLFLAG_TUN) != 0 && 516 (oidp->oid_kind & CTLFLAG_NOFETCH) == 0) { 517 /* only fetch value once */ 518 oidp->oid_kind |= CTLFLAG_NOFETCH; 519 /* try to fetch value from kernel environment */ 520 sysctl_load_tunable_by_oid_locked(oidp); 521 } 522 } 523 524 void 525 sysctl_register_disabled_oid(struct sysctl_oid *oidp) 526 { 527 528 /* 529 * Mark the leaf as dormant if it's not to be immediately enabled. 530 * We do not disable nodes as they can be shared between modules 531 * and it is always safe to access a node. 532 */ 533 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0, 534 ("internal flag is set in oid_kind")); 535 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 536 oidp->oid_kind |= CTLFLAG_DORMANT; 537 sysctl_register_oid(oidp); 538 } 539 540 void 541 sysctl_enable_oid(struct sysctl_oid *oidp) 542 { 543 544 SYSCTL_ASSERT_WLOCKED(); 545 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 546 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) == 0, 547 ("sysctl node is marked as dormant")); 548 return; 549 } 550 KASSERT((oidp->oid_kind & CTLFLAG_DORMANT) != 0, 551 ("enabling already enabled sysctl oid")); 552 oidp->oid_kind &= ~CTLFLAG_DORMANT; 553 } 554 555 void 556 sysctl_unregister_oid(struct sysctl_oid *oidp) 557 { 558 struct sysctl_oid *p; 559 int error; 560 561 SYSCTL_ASSERT_WLOCKED(); 562 if (oidp->oid_number == OID_AUTO) { 563 error = EINVAL; 564 } else { 565 error = ENOENT; 566 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 567 if (p == oidp) { 568 SLIST_REMOVE(oidp->oid_parent, oidp, 569 sysctl_oid, oid_link); 570 error = 0; 571 break; 572 } 573 } 574 } 575 576 /* 577 * This can happen when a module fails to register and is 578 * being unloaded afterwards. It should not be a panic() 579 * for normal use. 580 */ 581 if (error) { 582 printf("%s: failed(%d) to unregister sysctl(%s)\n", 583 __func__, error, oidp->oid_name); 584 } 585 } 586 587 /* Initialize a new context to keep track of dynamically added sysctls. */ 588 int 589 sysctl_ctx_init(struct sysctl_ctx_list *c) 590 { 591 592 if (c == NULL) { 593 return (EINVAL); 594 } 595 596 /* 597 * No locking here, the caller is responsible for not adding 598 * new nodes to a context until after this function has 599 * returned. 600 */ 601 TAILQ_INIT(c); 602 return (0); 603 } 604 605 /* Free the context, and destroy all dynamic oids registered in this context */ 606 int 607 sysctl_ctx_free(struct sysctl_ctx_list *clist) 608 { 609 struct sysctl_ctx_entry *e, *e1; 610 int error; 611 612 error = 0; 613 /* 614 * First perform a "dry run" to check if it's ok to remove oids. 615 * XXX FIXME 616 * XXX This algorithm is a hack. But I don't know any 617 * XXX better solution for now... 618 */ 619 SYSCTL_WLOCK(); 620 TAILQ_FOREACH(e, clist, link) { 621 error = sysctl_remove_oid_locked(e->entry, 0, 0); 622 if (error) 623 break; 624 } 625 /* 626 * Restore deregistered entries, either from the end, 627 * or from the place where error occurred. 628 * e contains the entry that was not unregistered 629 */ 630 if (error) 631 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 632 else 633 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 634 while (e1 != NULL) { 635 sysctl_register_oid(e1->entry); 636 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 637 } 638 if (error) { 639 SYSCTL_WUNLOCK(); 640 return(EBUSY); 641 } 642 /* Now really delete the entries */ 643 e = TAILQ_FIRST(clist); 644 while (e != NULL) { 645 e1 = TAILQ_NEXT(e, link); 646 error = sysctl_remove_oid_locked(e->entry, 1, 0); 647 if (error) 648 panic("sysctl_remove_oid: corrupt tree, entry: %s", 649 e->entry->oid_name); 650 free(e, M_SYSCTLOID); 651 e = e1; 652 } 653 SYSCTL_WUNLOCK(); 654 return (error); 655 } 656 657 /* Add an entry to the context */ 658 struct sysctl_ctx_entry * 659 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 660 { 661 struct sysctl_ctx_entry *e; 662 663 SYSCTL_ASSERT_WLOCKED(); 664 if (clist == NULL || oidp == NULL) 665 return(NULL); 666 e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 667 e->entry = oidp; 668 TAILQ_INSERT_HEAD(clist, e, link); 669 return (e); 670 } 671 672 /* Find an entry in the context */ 673 struct sysctl_ctx_entry * 674 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 675 { 676 struct sysctl_ctx_entry *e; 677 678 SYSCTL_ASSERT_WLOCKED(); 679 if (clist == NULL || oidp == NULL) 680 return(NULL); 681 TAILQ_FOREACH(e, clist, link) { 682 if(e->entry == oidp) 683 return(e); 684 } 685 return (e); 686 } 687 688 /* 689 * Delete an entry from the context. 690 * NOTE: this function doesn't free oidp! You have to remove it 691 * with sysctl_remove_oid(). 692 */ 693 int 694 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 695 { 696 struct sysctl_ctx_entry *e; 697 698 if (clist == NULL || oidp == NULL) 699 return (EINVAL); 700 SYSCTL_WLOCK(); 701 e = sysctl_ctx_entry_find(clist, oidp); 702 if (e != NULL) { 703 TAILQ_REMOVE(clist, e, link); 704 SYSCTL_WUNLOCK(); 705 free(e, M_SYSCTLOID); 706 return (0); 707 } else { 708 SYSCTL_WUNLOCK(); 709 return (ENOENT); 710 } 711 } 712 713 /* 714 * Remove dynamically created sysctl trees. 715 * oidp - top of the tree to be removed 716 * del - if 0 - just deregister, otherwise free up entries as well 717 * recurse - if != 0 traverse the subtree to be deleted 718 */ 719 int 720 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 721 { 722 int error; 723 724 SYSCTL_WLOCK(); 725 error = sysctl_remove_oid_locked(oidp, del, recurse); 726 SYSCTL_WUNLOCK(); 727 return (error); 728 } 729 730 int 731 sysctl_remove_name(struct sysctl_oid *parent, const char *name, 732 int del, int recurse) 733 { 734 struct sysctl_oid *p, *tmp; 735 int error; 736 737 error = ENOENT; 738 SYSCTL_WLOCK(); 739 SLIST_FOREACH_SAFE(p, SYSCTL_CHILDREN(parent), oid_link, tmp) { 740 if (strcmp(p->oid_name, name) == 0) { 741 error = sysctl_remove_oid_locked(p, del, recurse); 742 break; 743 } 744 } 745 SYSCTL_WUNLOCK(); 746 747 return (error); 748 } 749 750 static int 751 sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse) 752 { 753 struct sysctl_oid *p, *tmp; 754 int error; 755 756 SYSCTL_ASSERT_WLOCKED(); 757 if (oidp == NULL) 758 return(EINVAL); 759 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 760 printf("Warning: can't remove non-dynamic nodes (%s)!\n", 761 oidp->oid_name); 762 return (EINVAL); 763 } 764 /* 765 * WARNING: normal method to do this should be through 766 * sysctl_ctx_free(). Use recursing as the last resort 767 * method to purge your sysctl tree of leftovers... 768 * However, if some other code still references these nodes, 769 * it will panic. 770 */ 771 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 772 if (oidp->oid_refcnt == 1) { 773 SLIST_FOREACH_SAFE(p, 774 SYSCTL_CHILDREN(oidp), oid_link, tmp) { 775 if (!recurse) { 776 printf("Warning: failed attempt to " 777 "remove oid %s with child %s\n", 778 oidp->oid_name, p->oid_name); 779 return (ENOTEMPTY); 780 } 781 error = sysctl_remove_oid_locked(p, del, 782 recurse); 783 if (error) 784 return (error); 785 } 786 } 787 } 788 if (oidp->oid_refcnt > 1 ) { 789 oidp->oid_refcnt--; 790 } else { 791 if (oidp->oid_refcnt == 0) { 792 printf("Warning: bad oid_refcnt=%u (%s)!\n", 793 oidp->oid_refcnt, oidp->oid_name); 794 return (EINVAL); 795 } 796 sysctl_unregister_oid(oidp); 797 if (del) { 798 /* 799 * Wait for all threads running the handler to drain. 800 * This preserves the previous behavior when the 801 * sysctl lock was held across a handler invocation, 802 * and is necessary for module unload correctness. 803 */ 804 while (oidp->oid_running > 0) { 805 oidp->oid_kind |= CTLFLAG_DYING; 806 SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0); 807 } 808 if (oidp->oid_descr) 809 free(__DECONST(char *, oidp->oid_descr), 810 M_SYSCTLOID); 811 if (oidp->oid_label) 812 free(__DECONST(char *, oidp->oid_label), 813 M_SYSCTLOID); 814 free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); 815 free(oidp, M_SYSCTLOID); 816 } 817 } 818 return (0); 819 } 820 /* 821 * Create new sysctls at run time. 822 * clist may point to a valid context initialized with sysctl_ctx_init(). 823 */ 824 struct sysctl_oid * 825 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 826 int number, const char *name, int kind, void *arg1, intmax_t arg2, 827 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr, 828 const char *label) 829 { 830 struct sysctl_oid *oidp; 831 832 /* You have to hook up somewhere.. */ 833 if (parent == NULL) 834 return(NULL); 835 /* Check if the node already exists, otherwise create it */ 836 SYSCTL_WLOCK(); 837 oidp = sysctl_find_oidname(name, parent); 838 if (oidp != NULL) { 839 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 840 oidp->oid_refcnt++; 841 /* Update the context */ 842 if (clist != NULL) 843 sysctl_ctx_entry_add(clist, oidp); 844 SYSCTL_WUNLOCK(); 845 return (oidp); 846 } else { 847 sysctl_warn_reuse(__func__, oidp); 848 SYSCTL_WUNLOCK(); 849 return (NULL); 850 } 851 } 852 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO); 853 oidp->oid_parent = parent; 854 SLIST_INIT(&oidp->oid_children); 855 oidp->oid_number = number; 856 oidp->oid_refcnt = 1; 857 oidp->oid_name = strdup(name, M_SYSCTLOID); 858 oidp->oid_handler = handler; 859 oidp->oid_kind = CTLFLAG_DYN | kind; 860 oidp->oid_arg1 = arg1; 861 oidp->oid_arg2 = arg2; 862 oidp->oid_fmt = fmt; 863 if (descr != NULL) 864 oidp->oid_descr = strdup(descr, M_SYSCTLOID); 865 if (label != NULL) 866 oidp->oid_label = strdup(label, M_SYSCTLOID); 867 /* Update the context, if used */ 868 if (clist != NULL) 869 sysctl_ctx_entry_add(clist, oidp); 870 /* Register this oid */ 871 sysctl_register_oid(oidp); 872 SYSCTL_WUNLOCK(); 873 return (oidp); 874 } 875 876 /* 877 * Rename an existing oid. 878 */ 879 void 880 sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) 881 { 882 char *newname; 883 char *oldname; 884 885 newname = strdup(name, M_SYSCTLOID); 886 SYSCTL_WLOCK(); 887 oldname = __DECONST(char *, oidp->oid_name); 888 oidp->oid_name = newname; 889 SYSCTL_WUNLOCK(); 890 free(oldname, M_SYSCTLOID); 891 } 892 893 /* 894 * Reparent an existing oid. 895 */ 896 int 897 sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent) 898 { 899 struct sysctl_oid *oidp; 900 901 SYSCTL_WLOCK(); 902 if (oid->oid_parent == parent) { 903 SYSCTL_WUNLOCK(); 904 return (0); 905 } 906 oidp = sysctl_find_oidname(oid->oid_name, parent); 907 if (oidp != NULL) { 908 SYSCTL_WUNLOCK(); 909 return (EEXIST); 910 } 911 sysctl_unregister_oid(oid); 912 oid->oid_parent = parent; 913 oid->oid_number = OID_AUTO; 914 sysctl_register_oid(oid); 915 SYSCTL_WUNLOCK(); 916 return (0); 917 } 918 919 /* 920 * Register the kernel's oids on startup. 921 */ 922 SET_DECLARE(sysctl_set, struct sysctl_oid); 923 924 static void 925 sysctl_register_all(void *arg) 926 { 927 struct sysctl_oid **oidp; 928 929 sx_init(&sysctlmemlock, "sysctl mem"); 930 sx_init(&sysctlstringlock, "sysctl string handler"); 931 SYSCTL_INIT(); 932 SYSCTL_WLOCK(); 933 SET_FOREACH(oidp, sysctl_set) 934 sysctl_register_oid(*oidp); 935 SYSCTL_WUNLOCK(); 936 } 937 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, NULL); 938 939 /* 940 * "Staff-functions" 941 * 942 * These functions implement a presently undocumented interface 943 * used by the sysctl program to walk the tree, and get the type 944 * so it can print the value. 945 * This interface is under work and consideration, and should probably 946 * be killed with a big axe by the first person who can find the time. 947 * (be aware though, that the proper interface isn't as obvious as it 948 * may seem, there are various conflicting requirements. 949 * 950 * {CTL_SYSCTL, CTL_SYSCTL_DEBUG} printf the entire MIB-tree. 951 * {CTL_SYSCTL, CTL_SYSCTL_NAME, ...} return the name of the "..." 952 * OID. 953 * {CTL_SYSCTL, CTL_SYSCTL_NEXT, ...} return the next OID, honoring 954 * CTLFLAG_SKIP. 955 * {CTL_SYSCTL, CTL_SYSCTL_NAME2OID} return the OID of the name in 956 * "new" 957 * {CTL_SYSCTL, CTL_SYSCTL_OIDFMT, ...} return the kind & format info 958 * for the "..." OID. 959 * {CTL_SYSCTL, CTL_SYSCTL_OIDDESCR, ...} return the description of the 960 * "..." OID. 961 * {CTL_SYSCTL, CTL_SYSCTL_OIDLABEL, ...} return the aggregation label of 962 * the "..." OID. 963 * {CTL_SYSCTL, CTL_SYSCTL_NEXTNOSKIP, ...} return the next OID, ignoring 964 * CTLFLAG_SKIP. 965 */ 966 967 #ifdef SYSCTL_DEBUG 968 static void 969 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 970 { 971 int k; 972 struct sysctl_oid *oidp; 973 974 SYSCTL_ASSERT_LOCKED(); 975 SLIST_FOREACH(oidp, l, oid_link) { 976 for (k=0; k<i; k++) 977 printf(" "); 978 979 printf("%d %s ", oidp->oid_number, oidp->oid_name); 980 981 printf("%c%c", 982 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 983 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 984 985 if (oidp->oid_handler) 986 printf(" *Handler"); 987 988 switch (oidp->oid_kind & CTLTYPE) { 989 case CTLTYPE_NODE: 990 printf(" Node\n"); 991 if (!oidp->oid_handler) { 992 sysctl_sysctl_debug_dump_node( 993 SYSCTL_CHILDREN(oidp), i + 2); 994 } 995 break; 996 case CTLTYPE_INT: printf(" Int\n"); break; 997 case CTLTYPE_UINT: printf(" u_int\n"); break; 998 case CTLTYPE_LONG: printf(" Long\n"); break; 999 case CTLTYPE_ULONG: printf(" u_long\n"); break; 1000 case CTLTYPE_STRING: printf(" String\n"); break; 1001 case CTLTYPE_S8: printf(" int8_t\n"); break; 1002 case CTLTYPE_S16: printf(" int16_t\n"); break; 1003 case CTLTYPE_S32: printf(" int32_t\n"); break; 1004 case CTLTYPE_S64: printf(" int64_t\n"); break; 1005 case CTLTYPE_U8: printf(" uint8_t\n"); break; 1006 case CTLTYPE_U16: printf(" uint16_t\n"); break; 1007 case CTLTYPE_U32: printf(" uint32_t\n"); break; 1008 case CTLTYPE_U64: printf(" uint64_t\n"); break; 1009 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; 1010 default: printf("\n"); 1011 } 1012 } 1013 } 1014 1015 static int 1016 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 1017 { 1018 struct rm_priotracker tracker; 1019 int error; 1020 1021 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 1022 if (error) 1023 return (error); 1024 SYSCTL_RLOCK(&tracker); 1025 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 1026 SYSCTL_RUNLOCK(&tracker); 1027 return (ENOENT); 1028 } 1029 1030 SYSCTL_PROC(_sysctl, CTL_SYSCTL_DEBUG, debug, CTLTYPE_STRING | CTLFLAG_RD | 1031 CTLFLAG_MPSAFE, 0, 0, sysctl_sysctl_debug, "-", ""); 1032 #endif 1033 1034 static int 1035 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 1036 { 1037 int *name = (int *) arg1; 1038 u_int namelen = arg2; 1039 int error; 1040 struct sysctl_oid *oid; 1041 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 1042 struct rm_priotracker tracker; 1043 char buf[10]; 1044 1045 error = sysctl_wire_old_buffer(req, 0); 1046 if (error) 1047 return (error); 1048 1049 SYSCTL_RLOCK(&tracker); 1050 while (namelen) { 1051 if (!lsp) { 1052 snprintf(buf,sizeof(buf),"%d",*name); 1053 if (req->oldidx) 1054 error = SYSCTL_OUT(req, ".", 1); 1055 if (!error) 1056 error = SYSCTL_OUT(req, buf, strlen(buf)); 1057 if (error) 1058 goto out; 1059 namelen--; 1060 name++; 1061 continue; 1062 } 1063 lsp2 = NULL; 1064 SLIST_FOREACH(oid, lsp, oid_link) { 1065 if (oid->oid_number != *name) 1066 continue; 1067 1068 if (req->oldidx) 1069 error = SYSCTL_OUT(req, ".", 1); 1070 if (!error) 1071 error = SYSCTL_OUT(req, oid->oid_name, 1072 strlen(oid->oid_name)); 1073 if (error) 1074 goto out; 1075 1076 namelen--; 1077 name++; 1078 1079 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1080 break; 1081 1082 if (oid->oid_handler) 1083 break; 1084 1085 lsp2 = SYSCTL_CHILDREN(oid); 1086 break; 1087 } 1088 lsp = lsp2; 1089 } 1090 error = SYSCTL_OUT(req, "", 1); 1091 out: 1092 SYSCTL_RUNLOCK(&tracker); 1093 return (error); 1094 } 1095 1096 /* 1097 * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in 1098 * capability mode. 1099 */ 1100 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NAME, name, CTLFLAG_RD | 1101 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_name, ""); 1102 1103 /* 1104 * Walk the sysctl subtree at lsp until we find the given name, 1105 * and return the next name in order by oid_number. 1106 */ 1107 static int 1108 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 1109 int *next, int *len, int level, bool honor_skip) 1110 { 1111 struct sysctl_oid *oidp; 1112 1113 SYSCTL_ASSERT_LOCKED(); 1114 *len = level; 1115 SLIST_FOREACH(oidp, lsp, oid_link) { 1116 *next = oidp->oid_number; 1117 1118 if ((oidp->oid_kind & CTLFLAG_DORMANT) != 0) 1119 continue; 1120 1121 if (honor_skip && (oidp->oid_kind & CTLFLAG_SKIP) != 0) 1122 continue; 1123 1124 if (namelen == 0) { 1125 /* 1126 * We have reached a node with a full name match and are 1127 * looking for the next oid in its children. 1128 * 1129 * For CTL_SYSCTL_NEXTNOSKIP we are done. 1130 * 1131 * For CTL_SYSCTL_NEXT we skip CTLTYPE_NODE (unless it 1132 * has a handler) and move on to the children. 1133 */ 1134 if (!honor_skip) 1135 return (0); 1136 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1137 return (0); 1138 if (oidp->oid_handler) 1139 return (0); 1140 lsp = SYSCTL_CHILDREN(oidp); 1141 if (!sysctl_sysctl_next_ls(lsp, NULL, 0, next + 1, len, 1142 level + 1, honor_skip)) 1143 return (0); 1144 /* 1145 * There were no useable children in this node. 1146 * Continue searching for the next oid at this level. 1147 */ 1148 goto emptynode; 1149 } 1150 1151 /* 1152 * No match yet. Continue seeking the given name. 1153 * 1154 * We are iterating in order by oid_number, so skip oids lower 1155 * than the one we are looking for. 1156 * 1157 * When the current oid_number is higher than the one we seek, 1158 * that means we have reached the next oid in the sequence and 1159 * should return it. 1160 * 1161 * If the oid_number matches the name at this level then we 1162 * have to find a node to continue searching at the next level. 1163 */ 1164 if (oidp->oid_number < *name) 1165 continue; 1166 if (oidp->oid_number > *name) { 1167 /* 1168 * We have reached the next oid. 1169 * 1170 * For CTL_SYSCTL_NEXTNOSKIP we are done. 1171 * 1172 * For CTL_SYSCTL_NEXT we skip CTLTYPE_NODE (unless it 1173 * has a handler) and move on to the children. 1174 */ 1175 if (!honor_skip) 1176 return (0); 1177 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1178 return (0); 1179 if (oidp->oid_handler) 1180 return (0); 1181 lsp = SYSCTL_CHILDREN(oidp); 1182 if (!sysctl_sysctl_next_ls(lsp, name + 1, namelen - 1, 1183 next + 1, len, level + 1, honor_skip)) 1184 return (0); 1185 goto next; 1186 } 1187 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1188 continue; 1189 if (oidp->oid_handler) 1190 continue; 1191 lsp = SYSCTL_CHILDREN(oidp); 1192 if (!sysctl_sysctl_next_ls(lsp, name + 1, namelen - 1, 1193 next + 1, len, level + 1, honor_skip)) 1194 return (0); 1195 next: 1196 /* 1197 * There were no useable children in this node. 1198 * Continue searching for the next oid at the root level. 1199 */ 1200 namelen = 1; 1201 emptynode: 1202 /* Reset len in case a failed recursive call changed it. */ 1203 *len = level; 1204 } 1205 return (ENOENT); 1206 } 1207 1208 static int 1209 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 1210 { 1211 int *name = (int *) arg1; 1212 u_int namelen = arg2; 1213 int len, error; 1214 struct sysctl_oid_list *lsp = &sysctl__children; 1215 struct rm_priotracker tracker; 1216 int next[CTL_MAXNAME]; 1217 1218 SYSCTL_RLOCK(&tracker); 1219 error = sysctl_sysctl_next_ls(lsp, name, namelen, next, &len, 1, 1220 oidp->oid_number == CTL_SYSCTL_NEXT); 1221 SYSCTL_RUNLOCK(&tracker); 1222 if (error) 1223 return (error); 1224 error = SYSCTL_OUT(req, next, len * sizeof (int)); 1225 return (error); 1226 } 1227 1228 /* 1229 * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in 1230 * capability mode. 1231 */ 1232 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXT, next, CTLFLAG_RD | 1233 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, ""); 1234 1235 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_NEXTNOSKIP, nextnoskip, CTLFLAG_RD | 1236 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_next, ""); 1237 1238 static int 1239 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) 1240 { 1241 struct sysctl_oid *oidp; 1242 struct sysctl_oid_list *lsp = &sysctl__children; 1243 char *p; 1244 1245 SYSCTL_ASSERT_LOCKED(); 1246 1247 for (*len = 0; *len < CTL_MAXNAME;) { 1248 p = strsep(&name, "."); 1249 1250 oidp = SLIST_FIRST(lsp); 1251 for (;; oidp = SLIST_NEXT(oidp, oid_link)) { 1252 if (oidp == NULL) 1253 return (ENOENT); 1254 if (strcmp(p, oidp->oid_name) == 0) 1255 break; 1256 } 1257 *oid++ = oidp->oid_number; 1258 (*len)++; 1259 1260 if (name == NULL || *name == '\0') { 1261 if (oidpp) 1262 *oidpp = oidp; 1263 return (0); 1264 } 1265 1266 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1267 break; 1268 1269 if (oidp->oid_handler) 1270 break; 1271 1272 lsp = SYSCTL_CHILDREN(oidp); 1273 } 1274 return (ENOENT); 1275 } 1276 1277 static int 1278 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 1279 { 1280 char *p; 1281 int error, oid[CTL_MAXNAME], len = 0; 1282 struct sysctl_oid *op = NULL; 1283 struct rm_priotracker tracker; 1284 char buf[32]; 1285 1286 if (!req->newlen) 1287 return (ENOENT); 1288 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 1289 return (ENAMETOOLONG); 1290 1291 p = buf; 1292 if (req->newlen >= sizeof(buf)) 1293 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); 1294 1295 error = SYSCTL_IN(req, p, req->newlen); 1296 if (error) { 1297 if (p != buf) 1298 free(p, M_SYSCTL); 1299 return (error); 1300 } 1301 1302 p [req->newlen] = '\0'; 1303 1304 SYSCTL_RLOCK(&tracker); 1305 error = name2oid(p, oid, &len, &op); 1306 SYSCTL_RUNLOCK(&tracker); 1307 1308 if (p != buf) 1309 free(p, M_SYSCTL); 1310 1311 if (error) 1312 return (error); 1313 1314 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 1315 return (error); 1316 } 1317 1318 /* 1319 * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in 1320 * capability mode. 1321 */ 1322 SYSCTL_PROC(_sysctl, CTL_SYSCTL_NAME2OID, name2oid, CTLTYPE_INT | CTLFLAG_RW | 1323 CTLFLAG_ANYBODY | CTLFLAG_MPSAFE | CTLFLAG_CAPRW, 0, 0, 1324 sysctl_sysctl_name2oid, "I", ""); 1325 1326 static int 1327 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 1328 { 1329 struct sysctl_oid *oid; 1330 struct rm_priotracker tracker; 1331 int error; 1332 1333 error = sysctl_wire_old_buffer(req, 0); 1334 if (error) 1335 return (error); 1336 1337 SYSCTL_RLOCK(&tracker); 1338 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1339 if (error) 1340 goto out; 1341 1342 if (oid->oid_fmt == NULL) { 1343 error = ENOENT; 1344 goto out; 1345 } 1346 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 1347 if (error) 1348 goto out; 1349 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 1350 out: 1351 SYSCTL_RUNLOCK(&tracker); 1352 return (error); 1353 } 1354 1355 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDFMT, oidfmt, CTLFLAG_RD | 1356 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidfmt, ""); 1357 1358 static int 1359 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 1360 { 1361 struct sysctl_oid *oid; 1362 struct rm_priotracker tracker; 1363 int error; 1364 1365 error = sysctl_wire_old_buffer(req, 0); 1366 if (error) 1367 return (error); 1368 1369 SYSCTL_RLOCK(&tracker); 1370 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1371 if (error) 1372 goto out; 1373 1374 if (oid->oid_descr == NULL) { 1375 error = ENOENT; 1376 goto out; 1377 } 1378 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 1379 out: 1380 SYSCTL_RUNLOCK(&tracker); 1381 return (error); 1382 } 1383 1384 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDDESCR, oiddescr, CTLFLAG_RD | 1385 CTLFLAG_MPSAFE|CTLFLAG_CAPRD, sysctl_sysctl_oiddescr, ""); 1386 1387 static int 1388 sysctl_sysctl_oidlabel(SYSCTL_HANDLER_ARGS) 1389 { 1390 struct sysctl_oid *oid; 1391 struct rm_priotracker tracker; 1392 int error; 1393 1394 error = sysctl_wire_old_buffer(req, 0); 1395 if (error) 1396 return (error); 1397 1398 SYSCTL_RLOCK(&tracker); 1399 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1400 if (error) 1401 goto out; 1402 1403 if (oid->oid_label == NULL) { 1404 error = ENOENT; 1405 goto out; 1406 } 1407 error = SYSCTL_OUT(req, oid->oid_label, strlen(oid->oid_label) + 1); 1408 out: 1409 SYSCTL_RUNLOCK(&tracker); 1410 return (error); 1411 } 1412 1413 static SYSCTL_NODE(_sysctl, CTL_SYSCTL_OIDLABEL, oidlabel, CTLFLAG_RD | 1414 CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidlabel, ""); 1415 1416 /* 1417 * Default "handler" functions. 1418 */ 1419 1420 /* 1421 * Handle a bool. 1422 * Two cases: 1423 * a variable: point arg1 at it. 1424 * a constant: pass it in arg2. 1425 */ 1426 1427 int 1428 sysctl_handle_bool(SYSCTL_HANDLER_ARGS) 1429 { 1430 uint8_t temp; 1431 int error; 1432 1433 /* 1434 * Attempt to get a coherent snapshot by making a copy of the data. 1435 */ 1436 if (arg1) 1437 temp = *(bool *)arg1 ? 1 : 0; 1438 else 1439 temp = arg2 ? 1 : 0; 1440 1441 error = SYSCTL_OUT(req, &temp, sizeof(temp)); 1442 if (error || !req->newptr) 1443 return (error); 1444 1445 if (!arg1) 1446 error = EPERM; 1447 else { 1448 error = SYSCTL_IN(req, &temp, sizeof(temp)); 1449 if (!error) 1450 *(bool *)arg1 = temp ? 1 : 0; 1451 } 1452 return (error); 1453 } 1454 1455 /* 1456 * Handle an int8_t, signed or unsigned. 1457 * Two cases: 1458 * a variable: point arg1 at it. 1459 * a constant: pass it in arg2. 1460 */ 1461 1462 int 1463 sysctl_handle_8(SYSCTL_HANDLER_ARGS) 1464 { 1465 int8_t tmpout; 1466 int error = 0; 1467 1468 /* 1469 * Attempt to get a coherent snapshot by making a copy of the data. 1470 */ 1471 if (arg1) 1472 tmpout = *(int8_t *)arg1; 1473 else 1474 tmpout = arg2; 1475 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1476 1477 if (error || !req->newptr) 1478 return (error); 1479 1480 if (!arg1) 1481 error = EPERM; 1482 else 1483 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1484 return (error); 1485 } 1486 1487 /* 1488 * Handle an int16_t, signed or unsigned. 1489 * Two cases: 1490 * a variable: point arg1 at it. 1491 * a constant: pass it in arg2. 1492 */ 1493 1494 int 1495 sysctl_handle_16(SYSCTL_HANDLER_ARGS) 1496 { 1497 int16_t tmpout; 1498 int error = 0; 1499 1500 /* 1501 * Attempt to get a coherent snapshot by making a copy of the data. 1502 */ 1503 if (arg1) 1504 tmpout = *(int16_t *)arg1; 1505 else 1506 tmpout = arg2; 1507 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1508 1509 if (error || !req->newptr) 1510 return (error); 1511 1512 if (!arg1) 1513 error = EPERM; 1514 else 1515 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1516 return (error); 1517 } 1518 1519 /* 1520 * Handle an int32_t, signed or unsigned. 1521 * Two cases: 1522 * a variable: point arg1 at it. 1523 * a constant: pass it in arg2. 1524 */ 1525 1526 int 1527 sysctl_handle_32(SYSCTL_HANDLER_ARGS) 1528 { 1529 int32_t tmpout; 1530 int error = 0; 1531 1532 /* 1533 * Attempt to get a coherent snapshot by making a copy of the data. 1534 */ 1535 if (arg1) 1536 tmpout = *(int32_t *)arg1; 1537 else 1538 tmpout = arg2; 1539 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1540 1541 if (error || !req->newptr) 1542 return (error); 1543 1544 if (!arg1) 1545 error = EPERM; 1546 else 1547 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1548 return (error); 1549 } 1550 1551 /* 1552 * Handle an int, signed or unsigned. 1553 * Two cases: 1554 * a variable: point arg1 at it. 1555 * a constant: pass it in arg2. 1556 */ 1557 1558 int 1559 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 1560 { 1561 int tmpout, error = 0; 1562 1563 /* 1564 * Attempt to get a coherent snapshot by making a copy of the data. 1565 */ 1566 if (arg1) 1567 tmpout = *(int *)arg1; 1568 else 1569 tmpout = arg2; 1570 error = SYSCTL_OUT(req, &tmpout, sizeof(int)); 1571 1572 if (error || !req->newptr) 1573 return (error); 1574 1575 if (!arg1) 1576 error = EPERM; 1577 else 1578 error = SYSCTL_IN(req, arg1, sizeof(int)); 1579 return (error); 1580 } 1581 1582 /* 1583 * Based on on sysctl_handle_int() convert milliseconds into ticks. 1584 * Note: this is used by TCP. 1585 */ 1586 1587 int 1588 sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) 1589 { 1590 int error, s, tt; 1591 1592 tt = *(int *)arg1; 1593 s = (int)((int64_t)tt * 1000 / hz); 1594 1595 error = sysctl_handle_int(oidp, &s, 0, req); 1596 if (error || !req->newptr) 1597 return (error); 1598 1599 tt = (int)((int64_t)s * hz / 1000); 1600 if (tt < 1) 1601 return (EINVAL); 1602 1603 *(int *)arg1 = tt; 1604 return (0); 1605 } 1606 1607 /* 1608 * Handle a long, signed or unsigned. 1609 * Two cases: 1610 * a variable: point arg1 at it. 1611 * a constant: pass it in arg2. 1612 */ 1613 1614 int 1615 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 1616 { 1617 int error = 0; 1618 long tmplong; 1619 #ifdef SCTL_MASK32 1620 int tmpint; 1621 #endif 1622 1623 /* 1624 * Attempt to get a coherent snapshot by making a copy of the data. 1625 */ 1626 if (arg1) 1627 tmplong = *(long *)arg1; 1628 else 1629 tmplong = arg2; 1630 #ifdef SCTL_MASK32 1631 if (req->flags & SCTL_MASK32) { 1632 tmpint = tmplong; 1633 error = SYSCTL_OUT(req, &tmpint, sizeof(int)); 1634 } else 1635 #endif 1636 error = SYSCTL_OUT(req, &tmplong, sizeof(long)); 1637 1638 if (error || !req->newptr) 1639 return (error); 1640 1641 if (!arg1) 1642 error = EPERM; 1643 #ifdef SCTL_MASK32 1644 else if (req->flags & SCTL_MASK32) { 1645 error = SYSCTL_IN(req, &tmpint, sizeof(int)); 1646 *(long *)arg1 = (long)tmpint; 1647 } 1648 #endif 1649 else 1650 error = SYSCTL_IN(req, arg1, sizeof(long)); 1651 return (error); 1652 } 1653 1654 /* 1655 * Handle a 64 bit int, signed or unsigned. 1656 * Two cases: 1657 * a variable: point arg1 at it. 1658 * a constant: pass it in arg2. 1659 */ 1660 int 1661 sysctl_handle_64(SYSCTL_HANDLER_ARGS) 1662 { 1663 int error = 0; 1664 uint64_t tmpout; 1665 1666 /* 1667 * Attempt to get a coherent snapshot by making a copy of the data. 1668 */ 1669 if (arg1) 1670 tmpout = *(uint64_t *)arg1; 1671 else 1672 tmpout = arg2; 1673 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t)); 1674 1675 if (error || !req->newptr) 1676 return (error); 1677 1678 if (!arg1) 1679 error = EPERM; 1680 else 1681 error = SYSCTL_IN(req, arg1, sizeof(uint64_t)); 1682 return (error); 1683 } 1684 1685 /* 1686 * Handle our generic '\0' terminated 'C' string. 1687 * Two cases: 1688 * a variable string: point arg1 at it, arg2 is max length. 1689 * a constant string: point arg1 at it, arg2 is zero. 1690 */ 1691 1692 int 1693 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 1694 { 1695 char *tmparg; 1696 size_t outlen; 1697 int error = 0, ro_string = 0; 1698 1699 /* 1700 * If the sysctl isn't writable and isn't a preallocated tunable that 1701 * can be modified by kenv(2), microoptimise and treat it as a 1702 * read-only string. 1703 * A zero-length buffer indicates a fixed size read-only 1704 * string. In ddb, don't worry about trying to make a malloced 1705 * snapshot. 1706 */ 1707 if ((oidp->oid_kind & (CTLFLAG_WR | CTLFLAG_TUN)) == 0 || 1708 arg2 == 0 || kdb_active) { 1709 arg2 = strlen((char *)arg1) + 1; 1710 ro_string = 1; 1711 } 1712 1713 if (req->oldptr != NULL) { 1714 if (ro_string) { 1715 tmparg = arg1; 1716 outlen = strlen(tmparg) + 1; 1717 } else { 1718 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1719 sx_slock(&sysctlstringlock); 1720 memcpy(tmparg, arg1, arg2); 1721 sx_sunlock(&sysctlstringlock); 1722 outlen = strlen(tmparg) + 1; 1723 } 1724 1725 error = SYSCTL_OUT(req, tmparg, outlen); 1726 1727 if (!ro_string) 1728 free(tmparg, M_SYSCTLTMP); 1729 } else { 1730 if (!ro_string) 1731 sx_slock(&sysctlstringlock); 1732 outlen = strlen((char *)arg1) + 1; 1733 if (!ro_string) 1734 sx_sunlock(&sysctlstringlock); 1735 error = SYSCTL_OUT(req, NULL, outlen); 1736 } 1737 if (error || !req->newptr) 1738 return (error); 1739 1740 if (req->newlen - req->newidx >= arg2 || 1741 req->newlen - req->newidx < 0) { 1742 error = EINVAL; 1743 } else if (req->newlen - req->newidx == 0) { 1744 sx_xlock(&sysctlstringlock); 1745 ((char *)arg1)[0] = '\0'; 1746 sx_xunlock(&sysctlstringlock); 1747 } else { 1748 arg2 = req->newlen - req->newidx; 1749 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1750 1751 error = SYSCTL_IN(req, tmparg, arg2); 1752 if (error) { 1753 free(tmparg, M_SYSCTLTMP); 1754 return (error); 1755 } 1756 1757 sx_xlock(&sysctlstringlock); 1758 memcpy(arg1, tmparg, arg2); 1759 ((char *)arg1)[arg2] = '\0'; 1760 sx_xunlock(&sysctlstringlock); 1761 free(tmparg, M_SYSCTLTMP); 1762 req->newidx += arg2; 1763 } 1764 return (error); 1765 } 1766 1767 /* 1768 * Handle any kind of opaque data. 1769 * arg1 points to it, arg2 is the size. 1770 */ 1771 1772 int 1773 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 1774 { 1775 int error, tries; 1776 u_int generation; 1777 struct sysctl_req req2; 1778 1779 /* 1780 * Attempt to get a coherent snapshot, by using the thread 1781 * pre-emption counter updated from within mi_switch() to 1782 * determine if we were pre-empted during a bcopy() or 1783 * copyout(). Make 3 attempts at doing this before giving up. 1784 * If we encounter an error, stop immediately. 1785 */ 1786 tries = 0; 1787 req2 = *req; 1788 retry: 1789 generation = curthread->td_generation; 1790 error = SYSCTL_OUT(req, arg1, arg2); 1791 if (error) 1792 return (error); 1793 tries++; 1794 if (generation != curthread->td_generation && tries < 3) { 1795 *req = req2; 1796 goto retry; 1797 } 1798 1799 error = SYSCTL_IN(req, arg1, arg2); 1800 1801 return (error); 1802 } 1803 1804 /* 1805 * Based on on sysctl_handle_int() convert microseconds to a sbintime. 1806 */ 1807 int 1808 sysctl_usec_to_sbintime(SYSCTL_HANDLER_ARGS) 1809 { 1810 int error; 1811 int64_t tt; 1812 sbintime_t sb; 1813 1814 tt = *(int64_t *)arg1; 1815 sb = sbttous(tt); 1816 1817 error = sysctl_handle_64(oidp, &sb, 0, req); 1818 if (error || !req->newptr) 1819 return (error); 1820 1821 tt = ustosbt(sb); 1822 *(int64_t *)arg1 = tt; 1823 1824 return (0); 1825 } 1826 1827 /* 1828 * Based on on sysctl_handle_int() convert milliseconds to a sbintime. 1829 */ 1830 int 1831 sysctl_msec_to_sbintime(SYSCTL_HANDLER_ARGS) 1832 { 1833 int error; 1834 int64_t tt; 1835 sbintime_t sb; 1836 1837 tt = *(int64_t *)arg1; 1838 sb = sbttoms(tt); 1839 1840 error = sysctl_handle_64(oidp, &sb, 0, req); 1841 if (error || !req->newptr) 1842 return (error); 1843 1844 tt = mstosbt(sb); 1845 *(int64_t *)arg1 = tt; 1846 1847 return (0); 1848 } 1849 1850 /* 1851 * Convert seconds to a struct timeval. Intended for use with 1852 * intervals and thus does not permit negative seconds. 1853 */ 1854 int 1855 sysctl_sec_to_timeval(SYSCTL_HANDLER_ARGS) 1856 { 1857 struct timeval *tv; 1858 int error, secs; 1859 1860 tv = arg1; 1861 secs = tv->tv_sec; 1862 1863 error = sysctl_handle_int(oidp, &secs, 0, req); 1864 if (error || req->newptr == NULL) 1865 return (error); 1866 1867 if (secs < 0) 1868 return (EINVAL); 1869 tv->tv_sec = secs; 1870 1871 return (0); 1872 } 1873 1874 /* 1875 * Transfer functions to/from kernel space. 1876 * XXX: rather untested at this point 1877 */ 1878 static int 1879 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 1880 { 1881 size_t i = 0; 1882 1883 if (req->oldptr) { 1884 i = l; 1885 if (req->oldlen <= req->oldidx) 1886 i = 0; 1887 else 1888 if (i > req->oldlen - req->oldidx) 1889 i = req->oldlen - req->oldidx; 1890 if (i > 0) 1891 bcopy(p, (char *)req->oldptr + req->oldidx, i); 1892 } 1893 req->oldidx += l; 1894 if (req->oldptr && i != l) 1895 return (ENOMEM); 1896 return (0); 1897 } 1898 1899 static int 1900 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 1901 { 1902 if (!req->newptr) 1903 return (0); 1904 if (req->newlen - req->newidx < l) 1905 return (EINVAL); 1906 bcopy((const char *)req->newptr + req->newidx, p, l); 1907 req->newidx += l; 1908 return (0); 1909 } 1910 1911 int 1912 kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1913 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) 1914 { 1915 int error = 0; 1916 struct sysctl_req req; 1917 1918 bzero(&req, sizeof req); 1919 1920 req.td = td; 1921 req.flags = flags; 1922 1923 if (oldlenp) { 1924 req.oldlen = *oldlenp; 1925 } 1926 req.validlen = req.oldlen; 1927 1928 if (old) { 1929 req.oldptr= old; 1930 } 1931 1932 if (new != NULL) { 1933 req.newlen = newlen; 1934 req.newptr = new; 1935 } 1936 1937 req.oldfunc = sysctl_old_kernel; 1938 req.newfunc = sysctl_new_kernel; 1939 req.lock = REQ_UNWIRED; 1940 1941 error = sysctl_root(0, name, namelen, &req); 1942 1943 if (req.lock == REQ_WIRED && req.validlen > 0) 1944 vsunlock(req.oldptr, req.validlen); 1945 1946 if (error && error != ENOMEM) 1947 return (error); 1948 1949 if (retval) { 1950 if (req.oldptr && req.oldidx > req.validlen) 1951 *retval = req.validlen; 1952 else 1953 *retval = req.oldidx; 1954 } 1955 return (error); 1956 } 1957 1958 int 1959 kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp, 1960 void *new, size_t newlen, size_t *retval, int flags) 1961 { 1962 int oid[CTL_MAXNAME]; 1963 size_t oidlen, plen; 1964 int error; 1965 1966 oid[0] = CTL_SYSCTL; 1967 oid[1] = CTL_SYSCTL_NAME2OID; 1968 oidlen = sizeof(oid); 1969 1970 error = kernel_sysctl(td, oid, 2, oid, &oidlen, 1971 (void *)name, strlen(name), &plen, flags); 1972 if (error) 1973 return (error); 1974 1975 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp, 1976 new, newlen, retval, flags); 1977 return (error); 1978 } 1979 1980 /* 1981 * Transfer function to/from user space. 1982 */ 1983 static int 1984 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1985 { 1986 size_t i, len, origidx; 1987 int error; 1988 1989 origidx = req->oldidx; 1990 req->oldidx += l; 1991 if (req->oldptr == NULL) 1992 return (0); 1993 /* 1994 * If we have not wired the user supplied buffer and we are currently 1995 * holding locks, drop a witness warning, as it's possible that 1996 * write operations to the user page can sleep. 1997 */ 1998 if (req->lock != REQ_WIRED) 1999 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 2000 "sysctl_old_user()"); 2001 i = l; 2002 len = req->validlen; 2003 if (len <= origidx) 2004 i = 0; 2005 else { 2006 if (i > len - origidx) 2007 i = len - origidx; 2008 if (req->lock == REQ_WIRED) { 2009 error = copyout_nofault(p, (char *)req->oldptr + 2010 origidx, i); 2011 } else 2012 error = copyout(p, (char *)req->oldptr + origidx, i); 2013 if (error != 0) 2014 return (error); 2015 } 2016 if (i < l) 2017 return (ENOMEM); 2018 return (0); 2019 } 2020 2021 static int 2022 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 2023 { 2024 int error; 2025 2026 if (!req->newptr) 2027 return (0); 2028 if (req->newlen - req->newidx < l) 2029 return (EINVAL); 2030 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 2031 "sysctl_new_user()"); 2032 error = copyin((const char *)req->newptr + req->newidx, p, l); 2033 req->newidx += l; 2034 return (error); 2035 } 2036 2037 /* 2038 * Wire the user space destination buffer. If set to a value greater than 2039 * zero, the len parameter limits the maximum amount of wired memory. 2040 */ 2041 int 2042 sysctl_wire_old_buffer(struct sysctl_req *req, size_t len) 2043 { 2044 int ret; 2045 size_t wiredlen; 2046 2047 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen; 2048 ret = 0; 2049 if (req->lock != REQ_WIRED && req->oldptr && 2050 req->oldfunc == sysctl_old_user) { 2051 if (wiredlen != 0) { 2052 ret = vslock(req->oldptr, wiredlen); 2053 if (ret != 0) { 2054 if (ret != ENOMEM) 2055 return (ret); 2056 wiredlen = 0; 2057 } 2058 } 2059 req->lock = REQ_WIRED; 2060 req->validlen = wiredlen; 2061 } 2062 return (0); 2063 } 2064 2065 int 2066 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 2067 int *nindx, struct sysctl_req *req) 2068 { 2069 struct sysctl_oid_list *lsp; 2070 struct sysctl_oid *oid; 2071 int indx; 2072 2073 SYSCTL_ASSERT_LOCKED(); 2074 lsp = &sysctl__children; 2075 indx = 0; 2076 while (indx < CTL_MAXNAME) { 2077 SLIST_FOREACH(oid, lsp, oid_link) { 2078 if (oid->oid_number == name[indx]) 2079 break; 2080 } 2081 if (oid == NULL) 2082 return (ENOENT); 2083 2084 indx++; 2085 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2086 if (oid->oid_handler != NULL || indx == namelen) { 2087 *noid = oid; 2088 if (nindx != NULL) 2089 *nindx = indx; 2090 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 2091 ("%s found DYING node %p", __func__, oid)); 2092 return (0); 2093 } 2094 lsp = SYSCTL_CHILDREN(oid); 2095 } else if (indx == namelen) { 2096 if ((oid->oid_kind & CTLFLAG_DORMANT) != 0) 2097 return (ENOENT); 2098 *noid = oid; 2099 if (nindx != NULL) 2100 *nindx = indx; 2101 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 2102 ("%s found DYING node %p", __func__, oid)); 2103 return (0); 2104 } else { 2105 return (ENOTDIR); 2106 } 2107 } 2108 return (ENOENT); 2109 } 2110 2111 /* 2112 * Traverse our tree, and find the right node, execute whatever it points 2113 * to, and return the resulting error code. 2114 */ 2115 2116 static int 2117 sysctl_root(SYSCTL_HANDLER_ARGS) 2118 { 2119 struct sysctl_oid *oid; 2120 struct rm_priotracker tracker; 2121 int error, indx, lvl; 2122 2123 SYSCTL_RLOCK(&tracker); 2124 2125 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 2126 if (error) 2127 goto out; 2128 2129 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2130 /* 2131 * You can't call a sysctl when it's a node, but has 2132 * no handler. Inform the user that it's a node. 2133 * The indx may or may not be the same as namelen. 2134 */ 2135 if (oid->oid_handler == NULL) { 2136 error = EISDIR; 2137 goto out; 2138 } 2139 } 2140 2141 /* Is this sysctl writable? */ 2142 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) { 2143 error = EPERM; 2144 goto out; 2145 } 2146 2147 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL")); 2148 2149 #ifdef CAPABILITY_MODE 2150 /* 2151 * If the process is in capability mode, then don't permit reading or 2152 * writing unless specifically granted for the node. 2153 */ 2154 if (IN_CAPABILITY_MODE(req->td)) { 2155 if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) || 2156 (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) { 2157 error = EPERM; 2158 goto out; 2159 } 2160 } 2161 #endif 2162 2163 /* Is this sysctl sensitive to securelevels? */ 2164 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) { 2165 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE; 2166 error = securelevel_gt(req->td->td_ucred, lvl); 2167 if (error) 2168 goto out; 2169 } 2170 2171 /* Is this sysctl writable by only privileged users? */ 2172 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) { 2173 int priv; 2174 2175 if (oid->oid_kind & CTLFLAG_PRISON) 2176 priv = PRIV_SYSCTL_WRITEJAIL; 2177 #ifdef VIMAGE 2178 else if ((oid->oid_kind & CTLFLAG_VNET) && 2179 prison_owns_vnet(req->td->td_ucred)) 2180 priv = PRIV_SYSCTL_WRITEJAIL; 2181 #endif 2182 else 2183 priv = PRIV_SYSCTL_WRITE; 2184 error = priv_check(req->td, priv); 2185 if (error) 2186 goto out; 2187 } 2188 2189 if (!oid->oid_handler) { 2190 error = EINVAL; 2191 goto out; 2192 } 2193 2194 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2195 arg1 = (int *)arg1 + indx; 2196 arg2 -= indx; 2197 } else { 2198 arg1 = oid->oid_arg1; 2199 arg2 = oid->oid_arg2; 2200 } 2201 #ifdef MAC 2202 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2, 2203 req); 2204 if (error != 0) 2205 goto out; 2206 #endif 2207 #ifdef VIMAGE 2208 if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL) 2209 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1); 2210 #endif 2211 error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker); 2212 2213 out: 2214 SYSCTL_RUNLOCK(&tracker); 2215 return (error); 2216 } 2217 2218 #ifndef _SYS_SYSPROTO_H_ 2219 struct sysctl_args { 2220 int *name; 2221 u_int namelen; 2222 void *old; 2223 size_t *oldlenp; 2224 void *new; 2225 size_t newlen; 2226 }; 2227 #endif 2228 int 2229 sys___sysctl(struct thread *td, struct sysctl_args *uap) 2230 { 2231 int error, i, name[CTL_MAXNAME]; 2232 size_t j; 2233 2234 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 2235 return (EINVAL); 2236 2237 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 2238 if (error) 2239 return (error); 2240 2241 error = userland_sysctl(td, name, uap->namelen, 2242 uap->old, uap->oldlenp, 0, 2243 uap->new, uap->newlen, &j, 0); 2244 if (error && error != ENOMEM) 2245 return (error); 2246 if (uap->oldlenp) { 2247 i = copyout(&j, uap->oldlenp, sizeof(j)); 2248 if (i) 2249 return (i); 2250 } 2251 return (error); 2252 } 2253 2254 int 2255 kern___sysctlbyname(struct thread *td, const char *oname, size_t namelen, 2256 void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval, 2257 int flags, bool inkernel) 2258 { 2259 int oid[CTL_MAXNAME]; 2260 char namebuf[16]; 2261 char *name; 2262 size_t oidlen; 2263 int error; 2264 2265 if (namelen > MAXPATHLEN || namelen == 0) 2266 return (EINVAL); 2267 name = namebuf; 2268 if (namelen > sizeof(namebuf)) 2269 name = malloc(namelen, M_SYSCTL, M_WAITOK); 2270 error = copyin(oname, name, namelen); 2271 if (error != 0) 2272 goto out; 2273 2274 oid[0] = CTL_SYSCTL; 2275 oid[1] = CTL_SYSCTL_NAME2OID; 2276 oidlen = sizeof(oid); 2277 error = kernel_sysctl(td, oid, 2, oid, &oidlen, (void *)name, namelen, 2278 retval, flags); 2279 if (error != 0) 2280 goto out; 2281 error = userland_sysctl(td, oid, *retval / sizeof(int), old, oldlenp, 2282 inkernel, new, newlen, retval, flags); 2283 2284 out: 2285 if (namelen > sizeof(namebuf)) 2286 free(name, M_SYSCTL); 2287 return (error); 2288 } 2289 2290 #ifndef _SYS_SYSPROTO_H_ 2291 struct __sysctlbyname_args { 2292 const char *name; 2293 size_t namelen; 2294 void *old; 2295 size_t *oldlenp; 2296 void *new; 2297 size_t newlen; 2298 }; 2299 #endif 2300 int 2301 sys___sysctlbyname(struct thread *td, struct __sysctlbyname_args *uap) 2302 { 2303 size_t rv; 2304 int error; 2305 2306 error = kern___sysctlbyname(td, uap->name, uap->namelen, uap->old, 2307 uap->oldlenp, uap->new, uap->newlen, &rv, 0, 0); 2308 if (error != 0) 2309 return (error); 2310 if (uap->oldlenp != NULL) 2311 error = copyout(&rv, uap->oldlenp, sizeof(rv)); 2312 2313 return (error); 2314 } 2315 2316 /* 2317 * This is used from various compatibility syscalls too. That's why name 2318 * must be in kernel space. 2319 */ 2320 int 2321 userland_sysctl(struct thread *td, int *name, u_int namelen, void *old, 2322 size_t *oldlenp, int inkernel, const void *new, size_t newlen, 2323 size_t *retval, int flags) 2324 { 2325 int error = 0, memlocked; 2326 struct sysctl_req req; 2327 2328 bzero(&req, sizeof req); 2329 2330 req.td = td; 2331 req.flags = flags; 2332 2333 if (oldlenp) { 2334 if (inkernel) { 2335 req.oldlen = *oldlenp; 2336 } else { 2337 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 2338 if (error) 2339 return (error); 2340 } 2341 } 2342 req.validlen = req.oldlen; 2343 req.oldptr = old; 2344 2345 if (new != NULL) { 2346 req.newlen = newlen; 2347 req.newptr = new; 2348 } 2349 2350 req.oldfunc = sysctl_old_user; 2351 req.newfunc = sysctl_new_user; 2352 req.lock = REQ_UNWIRED; 2353 2354 #ifdef KTRACE 2355 if (KTRPOINT(curthread, KTR_SYSCTL)) 2356 ktrsysctl(name, namelen); 2357 #endif 2358 memlocked = 0; 2359 if (req.oldptr && req.oldlen > 4 * PAGE_SIZE) { 2360 memlocked = 1; 2361 sx_xlock(&sysctlmemlock); 2362 } 2363 CURVNET_SET(TD_TO_VNET(td)); 2364 2365 for (;;) { 2366 req.oldidx = 0; 2367 req.newidx = 0; 2368 error = sysctl_root(0, name, namelen, &req); 2369 if (error != EAGAIN) 2370 break; 2371 kern_yield(PRI_USER); 2372 } 2373 2374 CURVNET_RESTORE(); 2375 2376 if (req.lock == REQ_WIRED && req.validlen > 0) 2377 vsunlock(req.oldptr, req.validlen); 2378 if (memlocked) 2379 sx_xunlock(&sysctlmemlock); 2380 2381 if (error && error != ENOMEM) 2382 return (error); 2383 2384 if (retval) { 2385 if (req.oldptr && req.oldidx > req.validlen) 2386 *retval = req.validlen; 2387 else 2388 *retval = req.oldidx; 2389 } 2390 return (error); 2391 } 2392 2393 /* 2394 * Drain into a sysctl struct. The user buffer should be wired if a page 2395 * fault would cause issue. 2396 */ 2397 static int 2398 sbuf_sysctl_drain(void *arg, const char *data, int len) 2399 { 2400 struct sysctl_req *req = arg; 2401 int error; 2402 2403 error = SYSCTL_OUT(req, data, len); 2404 KASSERT(error >= 0, ("Got unexpected negative value %d", error)); 2405 return (error == 0 ? len : -error); 2406 } 2407 2408 struct sbuf * 2409 sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, 2410 struct sysctl_req *req) 2411 { 2412 2413 /* Supply a default buffer size if none given. */ 2414 if (buf == NULL && length == 0) 2415 length = 64; 2416 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL); 2417 sbuf_set_drain(s, sbuf_sysctl_drain, req); 2418 return (s); 2419 } 2420 2421 #ifdef DDB 2422 2423 /* The current OID the debugger is working with */ 2424 static struct sysctl_oid *g_ddb_oid; 2425 2426 /* The current flags specified by the user */ 2427 static int g_ddb_sysctl_flags; 2428 2429 /* Check to see if the last sysctl printed */ 2430 static int g_ddb_sysctl_printed; 2431 2432 static const int ctl_sign[CTLTYPE+1] = { 2433 [CTLTYPE_INT] = 1, 2434 [CTLTYPE_LONG] = 1, 2435 [CTLTYPE_S8] = 1, 2436 [CTLTYPE_S16] = 1, 2437 [CTLTYPE_S32] = 1, 2438 [CTLTYPE_S64] = 1, 2439 }; 2440 2441 static const int ctl_size[CTLTYPE+1] = { 2442 [CTLTYPE_INT] = sizeof(int), 2443 [CTLTYPE_UINT] = sizeof(u_int), 2444 [CTLTYPE_LONG] = sizeof(long), 2445 [CTLTYPE_ULONG] = sizeof(u_long), 2446 [CTLTYPE_S8] = sizeof(int8_t), 2447 [CTLTYPE_S16] = sizeof(int16_t), 2448 [CTLTYPE_S32] = sizeof(int32_t), 2449 [CTLTYPE_S64] = sizeof(int64_t), 2450 [CTLTYPE_U8] = sizeof(uint8_t), 2451 [CTLTYPE_U16] = sizeof(uint16_t), 2452 [CTLTYPE_U32] = sizeof(uint32_t), 2453 [CTLTYPE_U64] = sizeof(uint64_t), 2454 }; 2455 2456 #define DB_SYSCTL_NAME_ONLY 0x001 /* Compare with -N */ 2457 #define DB_SYSCTL_VALUE_ONLY 0x002 /* Compare with -n */ 2458 #define DB_SYSCTL_OPAQUE 0x004 /* Compare with -o */ 2459 #define DB_SYSCTL_HEX 0x008 /* Compare with -x */ 2460 2461 #define DB_SYSCTL_SAFE_ONLY 0x100 /* Only simple types */ 2462 2463 static const char db_sysctl_modifs[] = { 2464 'N', 'n', 'o', 'x', 2465 }; 2466 2467 static const int db_sysctl_modif_values[] = { 2468 DB_SYSCTL_NAME_ONLY, DB_SYSCTL_VALUE_ONLY, 2469 DB_SYSCTL_OPAQUE, DB_SYSCTL_HEX, 2470 }; 2471 2472 /* Handlers considered safe to print while recursing */ 2473 static int (* const db_safe_handlers[])(SYSCTL_HANDLER_ARGS) = { 2474 sysctl_handle_bool, 2475 sysctl_handle_8, 2476 sysctl_handle_16, 2477 sysctl_handle_32, 2478 sysctl_handle_64, 2479 sysctl_handle_int, 2480 sysctl_handle_long, 2481 sysctl_handle_string, 2482 sysctl_handle_opaque, 2483 }; 2484 2485 /* 2486 * Use in place of sysctl_old_kernel to print sysctl values. 2487 * 2488 * Compare to the output handling in show_var from sbin/sysctl/sysctl.c 2489 */ 2490 static int 2491 sysctl_old_ddb(struct sysctl_req *req, const void *ptr, size_t len) 2492 { 2493 const u_char *val, *p; 2494 const char *sep1; 2495 size_t intlen, slen; 2496 uintmax_t umv; 2497 intmax_t mv; 2498 int sign, ctltype, hexlen, xflag, error; 2499 2500 /* Suppress false-positive GCC uninitialized variable warnings */ 2501 mv = 0; 2502 umv = 0; 2503 2504 slen = len; 2505 val = p = ptr; 2506 2507 if (ptr == NULL) { 2508 error = 0; 2509 goto out; 2510 } 2511 2512 /* We are going to print */ 2513 g_ddb_sysctl_printed = 1; 2514 2515 xflag = g_ddb_sysctl_flags & DB_SYSCTL_HEX; 2516 2517 ctltype = (g_ddb_oid->oid_kind & CTLTYPE); 2518 sign = ctl_sign[ctltype]; 2519 intlen = ctl_size[ctltype]; 2520 2521 switch (ctltype) { 2522 case CTLTYPE_NODE: 2523 case CTLTYPE_STRING: 2524 db_printf("%.*s", (int) len, (const char *) p); 2525 error = 0; 2526 goto out; 2527 2528 case CTLTYPE_INT: 2529 case CTLTYPE_UINT: 2530 case CTLTYPE_LONG: 2531 case CTLTYPE_ULONG: 2532 case CTLTYPE_S8: 2533 case CTLTYPE_S16: 2534 case CTLTYPE_S32: 2535 case CTLTYPE_S64: 2536 case CTLTYPE_U8: 2537 case CTLTYPE_U16: 2538 case CTLTYPE_U32: 2539 case CTLTYPE_U64: 2540 hexlen = 2 + (intlen * CHAR_BIT + 3) / 4; 2541 sep1 = ""; 2542 while (len >= intlen) { 2543 switch (ctltype) { 2544 case CTLTYPE_INT: 2545 case CTLTYPE_UINT: 2546 umv = *(const u_int *)p; 2547 mv = *(const int *)p; 2548 break; 2549 case CTLTYPE_LONG: 2550 case CTLTYPE_ULONG: 2551 umv = *(const u_long *)p; 2552 mv = *(const long *)p; 2553 break; 2554 case CTLTYPE_S8: 2555 case CTLTYPE_U8: 2556 umv = *(const uint8_t *)p; 2557 mv = *(const int8_t *)p; 2558 break; 2559 case CTLTYPE_S16: 2560 case CTLTYPE_U16: 2561 umv = *(const uint16_t *)p; 2562 mv = *(const int16_t *)p; 2563 break; 2564 case CTLTYPE_S32: 2565 case CTLTYPE_U32: 2566 umv = *(const uint32_t *)p; 2567 mv = *(const int32_t *)p; 2568 break; 2569 case CTLTYPE_S64: 2570 case CTLTYPE_U64: 2571 umv = *(const uint64_t *)p; 2572 mv = *(const int64_t *)p; 2573 break; 2574 } 2575 2576 db_printf("%s", sep1); 2577 if (xflag) 2578 db_printf("%#0*jx", hexlen, umv); 2579 else if (!sign) 2580 db_printf("%ju", umv); 2581 else if (g_ddb_oid->oid_fmt[1] == 'K') { 2582 /* Kelvins are currently unsupported. */ 2583 error = EOPNOTSUPP; 2584 goto out; 2585 } else 2586 db_printf("%jd", mv); 2587 2588 sep1 = " "; 2589 len -= intlen; 2590 p += intlen; 2591 } 2592 error = 0; 2593 goto out; 2594 2595 case CTLTYPE_OPAQUE: 2596 /* TODO: Support struct functions. */ 2597 2598 /* FALLTHROUGH */ 2599 default: 2600 db_printf("Format:%s Length:%zu Dump:0x", 2601 g_ddb_oid->oid_fmt, len); 2602 while (len-- && (xflag || p < val + 16)) 2603 db_printf("%02x", *p++); 2604 if (!xflag && len > 16) 2605 db_printf("..."); 2606 error = 0; 2607 goto out; 2608 } 2609 2610 out: 2611 req->oldidx += slen; 2612 return (error); 2613 } 2614 2615 /* 2616 * Avoid setting new sysctl values from the debugger 2617 */ 2618 static int 2619 sysctl_new_ddb(struct sysctl_req *req, void *p, size_t l) 2620 { 2621 2622 if (!req->newptr) 2623 return (0); 2624 2625 /* Changing sysctls from the debugger is currently unsupported */ 2626 return (EPERM); 2627 } 2628 2629 /* 2630 * Run a sysctl handler with the DDB oldfunc and newfunc attached. 2631 * Instead of copying any output to a buffer we'll dump it right to 2632 * the console. 2633 */ 2634 static int 2635 db_sysctl(struct sysctl_oid *oidp, int *name, u_int namelen, 2636 void *old, size_t *oldlenp, size_t *retval, int flags) 2637 { 2638 struct sysctl_req req; 2639 int error; 2640 2641 /* Setup the request */ 2642 bzero(&req, sizeof req); 2643 req.td = kdb_thread; 2644 req.oldfunc = sysctl_old_ddb; 2645 req.newfunc = sysctl_new_ddb; 2646 req.lock = REQ_UNWIRED; 2647 if (oldlenp) { 2648 req.oldlen = *oldlenp; 2649 } 2650 req.validlen = req.oldlen; 2651 if (old) { 2652 req.oldptr = old; 2653 } 2654 2655 /* Setup our globals for sysctl_old_ddb */ 2656 g_ddb_oid = oidp; 2657 g_ddb_sysctl_flags = flags; 2658 g_ddb_sysctl_printed = 0; 2659 2660 error = sysctl_root(0, name, namelen, &req); 2661 2662 /* Reset globals */ 2663 g_ddb_oid = NULL; 2664 g_ddb_sysctl_flags = 0; 2665 2666 if (retval) { 2667 if (req.oldptr && req.oldidx > req.validlen) 2668 *retval = req.validlen; 2669 else 2670 *retval = req.oldidx; 2671 } 2672 return (error); 2673 } 2674 2675 /* 2676 * Show a sysctl's name 2677 */ 2678 static void 2679 db_show_oid_name(int *oid, size_t nlen) 2680 { 2681 struct sysctl_oid *oidp; 2682 int qoid[CTL_MAXNAME+2]; 2683 int error; 2684 2685 qoid[0] = 0; 2686 memcpy(qoid + 2, oid, nlen * sizeof(int)); 2687 qoid[1] = 1; 2688 2689 error = sysctl_find_oid(qoid, nlen + 2, &oidp, NULL, NULL); 2690 if (error) 2691 db_error("sysctl name oid"); 2692 2693 error = db_sysctl(oidp, qoid, nlen + 2, NULL, NULL, NULL, 0); 2694 if (error) 2695 db_error("sysctl name"); 2696 } 2697 2698 /* 2699 * Check to see if an OID is safe to print from ddb. 2700 */ 2701 static bool 2702 db_oid_safe(const struct sysctl_oid *oidp) 2703 { 2704 for (unsigned int i = 0; i < nitems(db_safe_handlers); ++i) { 2705 if (oidp->oid_handler == db_safe_handlers[i]) 2706 return (true); 2707 } 2708 2709 return (false); 2710 } 2711 2712 /* 2713 * Show a sysctl at a specific OID 2714 * Compare to the input handling in show_var from sbin/sysctl/sysctl.c 2715 */ 2716 static int 2717 db_show_oid(struct sysctl_oid *oidp, int *oid, size_t nlen, int flags) 2718 { 2719 int error, xflag, oflag, Nflag, nflag; 2720 size_t len; 2721 2722 xflag = flags & DB_SYSCTL_HEX; 2723 oflag = flags & DB_SYSCTL_OPAQUE; 2724 nflag = flags & DB_SYSCTL_VALUE_ONLY; 2725 Nflag = flags & DB_SYSCTL_NAME_ONLY; 2726 2727 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_OPAQUE && 2728 (!xflag && !oflag)) 2729 return (0); 2730 2731 if (Nflag) { 2732 db_show_oid_name(oid, nlen); 2733 error = 0; 2734 goto out; 2735 } 2736 2737 if (!nflag) { 2738 db_show_oid_name(oid, nlen); 2739 db_printf(": "); 2740 } 2741 2742 if ((flags & DB_SYSCTL_SAFE_ONLY) && !db_oid_safe(oidp)) { 2743 db_printf("Skipping, unsafe to print while recursing."); 2744 error = 0; 2745 goto out; 2746 } 2747 2748 /* Try once, and ask about the size */ 2749 len = 0; 2750 error = db_sysctl(oidp, oid, nlen, 2751 NULL, NULL, &len, flags); 2752 if (error) 2753 goto out; 2754 2755 if (!g_ddb_sysctl_printed) 2756 /* Lie about the size */ 2757 error = db_sysctl(oidp, oid, nlen, 2758 (void *) 1, &len, NULL, flags); 2759 2760 out: 2761 db_printf("\n"); 2762 return (error); 2763 } 2764 2765 /* 2766 * Show all sysctls under a specific OID 2767 * Compare to sysctl_all from sbin/sysctl/sysctl.c 2768 */ 2769 static int 2770 db_show_sysctl_all(int *oid, size_t len, int flags) 2771 { 2772 struct sysctl_oid *oidp; 2773 int name1[CTL_MAXNAME + 2], name2[CTL_MAXNAME + 2]; 2774 size_t l1, l2; 2775 2776 name1[0] = CTL_SYSCTL; 2777 name1[1] = CTL_SYSCTL_NEXT; 2778 l1 = 2; 2779 if (len) { 2780 memcpy(name1 + 2, oid, len * sizeof(int)); 2781 l1 += len; 2782 } else { 2783 name1[2] = CTL_KERN; 2784 l1++; 2785 } 2786 for (;;) { 2787 int i, error; 2788 2789 l2 = sizeof(name2); 2790 error = kernel_sysctl(kdb_thread, name1, l1, 2791 name2, &l2, NULL, 0, &l2, 0); 2792 if (error != 0) { 2793 if (error == ENOENT) 2794 return (0); 2795 else 2796 db_error("sysctl(next)"); 2797 } 2798 2799 l2 /= sizeof(int); 2800 2801 if (l2 < (unsigned int)len) 2802 return (0); 2803 2804 for (i = 0; i < len; i++) 2805 if (name2[i] != oid[i]) 2806 return (0); 2807 2808 /* Find the OID in question */ 2809 error = sysctl_find_oid(name2, l2, &oidp, NULL, NULL); 2810 if (error) 2811 return (error); 2812 2813 i = db_show_oid(oidp, name2, l2, flags | DB_SYSCTL_SAFE_ONLY); 2814 2815 if (db_pager_quit) 2816 return (0); 2817 2818 memcpy(name1+2, name2, l2 * sizeof(int)); 2819 l1 = 2 + l2; 2820 } 2821 } 2822 2823 /* 2824 * Show a sysctl by its user facing string 2825 */ 2826 static int 2827 db_sysctlbyname(char *name, int flags) 2828 { 2829 struct sysctl_oid *oidp; 2830 int oid[CTL_MAXNAME]; 2831 int error, nlen; 2832 2833 error = name2oid(name, oid, &nlen, &oidp); 2834 if (error) { 2835 return (error); 2836 } 2837 2838 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 2839 db_show_sysctl_all(oid, nlen, flags); 2840 } else { 2841 error = db_show_oid(oidp, oid, nlen, flags); 2842 } 2843 2844 return (error); 2845 } 2846 2847 static void 2848 db_sysctl_cmd_usage(void) 2849 { 2850 db_printf( 2851 " sysctl [/Nnox] <sysctl> \n" 2852 " \n" 2853 " <sysctl> The name of the sysctl to show. \n" 2854 " \n" 2855 " Show a sysctl by hooking into SYSCTL_IN and SYSCTL_OUT. \n" 2856 " This will work for most sysctls, but should not be used \n" 2857 " with sysctls that are known to malloc. \n" 2858 " \n" 2859 " While recursing any \"unsafe\" sysctls will be skipped. \n" 2860 " Call sysctl directly on the sysctl to try printing the \n" 2861 " skipped sysctl. This is unsafe and may make the ddb \n" 2862 " session unusable. \n" 2863 " \n" 2864 " Arguments: \n" 2865 " /N Display only the name of the sysctl. \n" 2866 " /n Display only the value of the sysctl. \n" 2867 " /o Display opaque values. \n" 2868 " /x Display the sysctl in hex. \n" 2869 " \n" 2870 "For example: \n" 2871 "sysctl vm.v_free_min \n" 2872 "vn.v_free_min: 12669 \n" 2873 ); 2874 } 2875 2876 /* 2877 * Show a specific sysctl similar to sysctl (8). 2878 */ 2879 DB_FUNC(sysctl, db_sysctl_cmd, db_cmd_table, CS_OWN, NULL) 2880 { 2881 char name[TOK_STRING_SIZE]; 2882 int error, i, t, flags; 2883 2884 /* Parse the modifiers */ 2885 t = db_read_token(); 2886 if (t == tSLASH || t == tMINUS) { 2887 t = db_read_token(); 2888 if (t != tIDENT) { 2889 db_printf("Bad modifier\n"); 2890 error = EINVAL; 2891 goto out; 2892 } 2893 db_strcpy(modif, db_tok_string); 2894 } 2895 else { 2896 db_unread_token(t); 2897 modif[0] = '\0'; 2898 } 2899 2900 flags = 0; 2901 for (i = 0; i < nitems(db_sysctl_modifs); i++) { 2902 if (strchr(modif, db_sysctl_modifs[i])) { 2903 flags |= db_sysctl_modif_values[i]; 2904 } 2905 } 2906 2907 /* Parse the sysctl names */ 2908 t = db_read_token(); 2909 if (t != tIDENT) { 2910 db_printf("Need sysctl name\n"); 2911 error = EINVAL; 2912 goto out; 2913 } 2914 2915 /* Copy the name into a temporary buffer */ 2916 db_strcpy(name, db_tok_string); 2917 2918 /* Ensure there is no trailing cruft */ 2919 t = db_read_token(); 2920 if (t != tEOL) { 2921 db_printf("Unexpected sysctl argument\n"); 2922 error = EINVAL; 2923 goto out; 2924 } 2925 2926 error = db_sysctlbyname(name, flags); 2927 if (error == ENOENT) { 2928 db_printf("unknown oid: '%s'\n", db_tok_string); 2929 goto out; 2930 } else if (error) { 2931 db_printf("%s: error: %d\n", db_tok_string, error); 2932 goto out; 2933 } 2934 2935 out: 2936 /* Ensure we eat all of our text */ 2937 db_flush_lex(); 2938 2939 if (error == EINVAL) { 2940 db_sysctl_cmd_usage(); 2941 } 2942 } 2943 2944 #endif /* DDB */ 2945