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