1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Mike Karels at Berkeley Software Design, Inc. 7 * 8 * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD 9 * project, to make these variables more userfriendly. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94 36 */ 37 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include "opt_capsicum.h" 42 #include "opt_compat.h" 43 #include "opt_ktrace.h" 44 45 #include <sys/param.h> 46 #include <sys/fail.h> 47 #include <sys/systm.h> 48 #include <sys/capsicum.h> 49 #include <sys/kernel.h> 50 #include <sys/sysctl.h> 51 #include <sys/malloc.h> 52 #include <sys/priv.h> 53 #include <sys/proc.h> 54 #include <sys/jail.h> 55 #include <sys/lock.h> 56 #include <sys/mutex.h> 57 #include <sys/rmlock.h> 58 #include <sys/sbuf.h> 59 #include <sys/sx.h> 60 #include <sys/sysproto.h> 61 #include <sys/uio.h> 62 #ifdef KTRACE 63 #include <sys/ktrace.h> 64 #endif 65 66 #include <net/vnet.h> 67 68 #include <security/mac/mac_framework.h> 69 70 #include <vm/vm.h> 71 #include <vm/vm_extern.h> 72 73 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic"); 74 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids"); 75 static MALLOC_DEFINE(M_SYSCTLTMP, "sysctltmp", "sysctl temp output buffer"); 76 77 /* 78 * The sysctllock protects the MIB tree. It also protects sysctl 79 * contexts used with dynamic sysctls. The sysctl_register_oid() and 80 * sysctl_unregister_oid() routines require the sysctllock to already 81 * be held, so the sysctl_wlock() and sysctl_wunlock() routines are 82 * provided for the few places in the kernel which need to use that 83 * API rather than using the dynamic API. Use of the dynamic API is 84 * strongly encouraged for most code. 85 * 86 * The sysctlmemlock is used to limit the amount of user memory wired for 87 * sysctl requests. This is implemented by serializing any userland 88 * sysctl requests larger than a single page via an exclusive lock. 89 */ 90 static struct rmlock sysctllock; 91 static struct sx sysctlmemlock; 92 93 #define SYSCTL_WLOCK() rm_wlock(&sysctllock) 94 #define SYSCTL_WUNLOCK() rm_wunlock(&sysctllock) 95 #define SYSCTL_RLOCK(tracker) rm_rlock(&sysctllock, (tracker)) 96 #define SYSCTL_RUNLOCK(tracker) rm_runlock(&sysctllock, (tracker)) 97 #define SYSCTL_WLOCKED() rm_wowned(&sysctllock) 98 #define SYSCTL_ASSERT_LOCKED() rm_assert(&sysctllock, RA_LOCKED) 99 #define SYSCTL_ASSERT_WLOCKED() rm_assert(&sysctllock, RA_WLOCKED) 100 #define SYSCTL_ASSERT_RLOCKED() rm_assert(&sysctllock, RA_RLOCKED) 101 #define SYSCTL_INIT() rm_init_flags(&sysctllock, "sysctl lock", \ 102 RM_SLEEPABLE) 103 #define SYSCTL_SLEEP(ch, wmesg, timo) \ 104 rm_sleep(ch, &sysctllock, 0, wmesg, timo) 105 106 static int sysctl_root(SYSCTL_HANDLER_ARGS); 107 108 /* Root list */ 109 struct sysctl_oid_list sysctl__children = SLIST_HEAD_INITIALIZER(&sysctl__children); 110 111 static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, 112 int recurse); 113 static int sysctl_old_kernel(struct sysctl_req *, const void *, size_t); 114 static int sysctl_new_kernel(struct sysctl_req *, void *, size_t); 115 116 static struct sysctl_oid * 117 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list) 118 { 119 struct sysctl_oid *oidp; 120 121 SYSCTL_ASSERT_LOCKED(); 122 SLIST_FOREACH(oidp, list, oid_link) { 123 if (strcmp(oidp->oid_name, name) == 0) { 124 return (oidp); 125 } 126 } 127 return (NULL); 128 } 129 130 /* 131 * Initialization of the MIB tree. 132 * 133 * Order by number in each list. 134 */ 135 void 136 sysctl_wlock(void) 137 { 138 139 SYSCTL_WLOCK(); 140 } 141 142 void 143 sysctl_wunlock(void) 144 { 145 146 SYSCTL_WUNLOCK(); 147 } 148 149 static int 150 sysctl_root_handler_locked(struct sysctl_oid *oid, void *arg1, intmax_t arg2, 151 struct sysctl_req *req, struct rm_priotracker *tracker) 152 { 153 int error; 154 155 if (oid->oid_kind & CTLFLAG_DYN) 156 atomic_add_int(&oid->oid_running, 1); 157 158 if (tracker != NULL) 159 SYSCTL_RUNLOCK(tracker); 160 else 161 SYSCTL_WUNLOCK(); 162 163 if (!(oid->oid_kind & CTLFLAG_MPSAFE)) 164 mtx_lock(&Giant); 165 error = oid->oid_handler(oid, arg1, arg2, req); 166 if (!(oid->oid_kind & CTLFLAG_MPSAFE)) 167 mtx_unlock(&Giant); 168 169 KFAIL_POINT_ERROR(_debug_fail_point, sysctl_running, error); 170 171 if (tracker != NULL) 172 SYSCTL_RLOCK(tracker); 173 else 174 SYSCTL_WLOCK(); 175 176 if (oid->oid_kind & CTLFLAG_DYN) { 177 if (atomic_fetchadd_int(&oid->oid_running, -1) == 1 && 178 (oid->oid_kind & CTLFLAG_DYING) != 0) 179 wakeup(&oid->oid_running); 180 } 181 182 return (error); 183 } 184 185 static void 186 sysctl_load_tunable_by_oid_locked(struct sysctl_oid *oidp) 187 { 188 struct sysctl_req req; 189 struct sysctl_oid *curr; 190 char *penv = NULL; 191 char path[64]; 192 ssize_t rem = sizeof(path); 193 ssize_t len; 194 uint8_t val_8; 195 uint16_t val_16; 196 uint32_t val_32; 197 int val_int; 198 long val_long; 199 int64_t val_64; 200 quad_t val_quad; 201 int error; 202 203 path[--rem] = 0; 204 205 for (curr = oidp; curr != NULL; curr = SYSCTL_PARENT(curr)) { 206 len = strlen(curr->oid_name); 207 rem -= len; 208 if (curr != oidp) 209 rem -= 1; 210 if (rem < 0) { 211 printf("OID path exceeds %d bytes\n", (int)sizeof(path)); 212 return; 213 } 214 memcpy(path + rem, curr->oid_name, len); 215 if (curr != oidp) 216 path[rem + len] = '.'; 217 } 218 219 memset(&req, 0, sizeof(req)); 220 221 req.td = curthread; 222 req.oldfunc = sysctl_old_kernel; 223 req.newfunc = sysctl_new_kernel; 224 req.lock = REQ_UNWIRED; 225 226 switch (oidp->oid_kind & CTLTYPE) { 227 case CTLTYPE_INT: 228 if (getenv_int(path + rem, &val_int) == 0) 229 return; 230 req.newlen = sizeof(val_int); 231 req.newptr = &val_int; 232 break; 233 case CTLTYPE_UINT: 234 if (getenv_uint(path + rem, (unsigned int *)&val_int) == 0) 235 return; 236 req.newlen = sizeof(val_int); 237 req.newptr = &val_int; 238 break; 239 case CTLTYPE_LONG: 240 if (getenv_long(path + rem, &val_long) == 0) 241 return; 242 req.newlen = sizeof(val_long); 243 req.newptr = &val_long; 244 break; 245 case CTLTYPE_ULONG: 246 if (getenv_ulong(path + rem, (unsigned long *)&val_long) == 0) 247 return; 248 req.newlen = sizeof(val_long); 249 req.newptr = &val_long; 250 break; 251 case CTLTYPE_S8: 252 if (getenv_int(path + rem, &val_int) == 0) 253 return; 254 val_8 = val_int; 255 req.newlen = sizeof(val_8); 256 req.newptr = &val_8; 257 break; 258 case CTLTYPE_S16: 259 if (getenv_int(path + rem, &val_int) == 0) 260 return; 261 val_16 = val_int; 262 req.newlen = sizeof(val_16); 263 req.newptr = &val_16; 264 break; 265 case CTLTYPE_S32: 266 if (getenv_long(path + rem, &val_long) == 0) 267 return; 268 val_32 = val_long; 269 req.newlen = sizeof(val_32); 270 req.newptr = &val_32; 271 break; 272 case CTLTYPE_S64: 273 if (getenv_quad(path + rem, &val_quad) == 0) 274 return; 275 val_64 = val_quad; 276 req.newlen = sizeof(val_64); 277 req.newptr = &val_64; 278 break; 279 case CTLTYPE_U8: 280 if (getenv_uint(path + rem, (unsigned int *)&val_int) == 0) 281 return; 282 val_8 = val_int; 283 req.newlen = sizeof(val_8); 284 req.newptr = &val_8; 285 break; 286 case CTLTYPE_U16: 287 if (getenv_uint(path + rem, (unsigned int *)&val_int) == 0) 288 return; 289 val_16 = val_int; 290 req.newlen = sizeof(val_16); 291 req.newptr = &val_16; 292 break; 293 case CTLTYPE_U32: 294 if (getenv_ulong(path + rem, (unsigned long *)&val_long) == 0) 295 return; 296 val_32 = val_long; 297 req.newlen = sizeof(val_32); 298 req.newptr = &val_32; 299 break; 300 case CTLTYPE_U64: 301 /* XXX there is no getenv_uquad() */ 302 if (getenv_quad(path + rem, &val_quad) == 0) 303 return; 304 val_64 = val_quad; 305 req.newlen = sizeof(val_64); 306 req.newptr = &val_64; 307 break; 308 case CTLTYPE_STRING: 309 penv = kern_getenv(path + rem); 310 if (penv == NULL) 311 return; 312 req.newlen = strlen(penv); 313 req.newptr = penv; 314 break; 315 default: 316 return; 317 } 318 error = sysctl_root_handler_locked(oidp, oidp->oid_arg1, 319 oidp->oid_arg2, &req, NULL); 320 if (error != 0) 321 printf("Setting sysctl %s failed: %d\n", path + rem, error); 322 if (penv != NULL) 323 freeenv(penv); 324 } 325 326 void 327 sysctl_register_oid(struct sysctl_oid *oidp) 328 { 329 struct sysctl_oid_list *parent = oidp->oid_parent; 330 struct sysctl_oid *p; 331 struct sysctl_oid *q; 332 int oid_number; 333 int timeout = 2; 334 335 /* 336 * First check if another oid with the same name already 337 * exists in the parent's list. 338 */ 339 SYSCTL_ASSERT_WLOCKED(); 340 p = sysctl_find_oidname(oidp->oid_name, parent); 341 if (p != NULL) { 342 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 343 p->oid_refcnt++; 344 return; 345 } else { 346 printf("can't re-use a leaf (%s)!\n", p->oid_name); 347 return; 348 } 349 } 350 /* get current OID number */ 351 oid_number = oidp->oid_number; 352 353 #if (OID_AUTO >= 0) 354 #error "OID_AUTO is expected to be a negative value" 355 #endif 356 /* 357 * Any negative OID number qualifies as OID_AUTO. Valid OID 358 * numbers should always be positive. 359 * 360 * NOTE: DO NOT change the starting value here, change it in 361 * <sys/sysctl.h>, and make sure it is at least 256 to 362 * accommodate e.g. net.inet.raw as a static sysctl node. 363 */ 364 if (oid_number < 0) { 365 static int newoid; 366 367 /* 368 * By decrementing the next OID number we spend less 369 * time inserting the OIDs into a sorted list. 370 */ 371 if (--newoid < CTL_AUTO_START) 372 newoid = 0x7fffffff; 373 374 oid_number = newoid; 375 } 376 377 /* 378 * Insert the OID into the parent's list sorted by OID number. 379 */ 380 retry: 381 q = NULL; 382 SLIST_FOREACH(p, parent, oid_link) { 383 /* check if the current OID number is in use */ 384 if (oid_number == p->oid_number) { 385 /* get the next valid OID number */ 386 if (oid_number < CTL_AUTO_START || 387 oid_number == 0x7fffffff) { 388 /* wraparound - restart */ 389 oid_number = CTL_AUTO_START; 390 /* don't loop forever */ 391 if (!timeout--) 392 panic("sysctl: Out of OID numbers\n"); 393 goto retry; 394 } else { 395 oid_number++; 396 } 397 } else if (oid_number < p->oid_number) 398 break; 399 q = p; 400 } 401 /* check for non-auto OID number collision */ 402 if (oidp->oid_number >= 0 && oidp->oid_number < CTL_AUTO_START && 403 oid_number >= CTL_AUTO_START) { 404 printf("sysctl: OID number(%d) is already in use for '%s'\n", 405 oidp->oid_number, oidp->oid_name); 406 } 407 /* update the OID number, if any */ 408 oidp->oid_number = oid_number; 409 if (q != NULL) 410 SLIST_INSERT_AFTER(q, oidp, oid_link); 411 else 412 SLIST_INSERT_HEAD(parent, oidp, oid_link); 413 414 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE && 415 #ifdef VIMAGE 416 (oidp->oid_kind & CTLFLAG_VNET) == 0 && 417 #endif 418 (oidp->oid_kind & CTLFLAG_TUN) != 0 && 419 (oidp->oid_kind & CTLFLAG_NOFETCH) == 0) { 420 /* only fetch value once */ 421 oidp->oid_kind |= CTLFLAG_NOFETCH; 422 /* try to fetch value from kernel environment */ 423 sysctl_load_tunable_by_oid_locked(oidp); 424 } 425 } 426 427 void 428 sysctl_unregister_oid(struct sysctl_oid *oidp) 429 { 430 struct sysctl_oid *p; 431 int error; 432 433 SYSCTL_ASSERT_WLOCKED(); 434 error = ENOENT; 435 if (oidp->oid_number == OID_AUTO) { 436 error = EINVAL; 437 } else { 438 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 439 if (p == oidp) { 440 SLIST_REMOVE(oidp->oid_parent, oidp, 441 sysctl_oid, oid_link); 442 error = 0; 443 break; 444 } 445 } 446 } 447 448 /* 449 * This can happen when a module fails to register and is 450 * being unloaded afterwards. It should not be a panic() 451 * for normal use. 452 */ 453 if (error) 454 printf("%s: failed to unregister sysctl\n", __func__); 455 } 456 457 /* Initialize a new context to keep track of dynamically added sysctls. */ 458 int 459 sysctl_ctx_init(struct sysctl_ctx_list *c) 460 { 461 462 if (c == NULL) { 463 return (EINVAL); 464 } 465 466 /* 467 * No locking here, the caller is responsible for not adding 468 * new nodes to a context until after this function has 469 * returned. 470 */ 471 TAILQ_INIT(c); 472 return (0); 473 } 474 475 /* Free the context, and destroy all dynamic oids registered in this context */ 476 int 477 sysctl_ctx_free(struct sysctl_ctx_list *clist) 478 { 479 struct sysctl_ctx_entry *e, *e1; 480 int error; 481 482 error = 0; 483 /* 484 * First perform a "dry run" to check if it's ok to remove oids. 485 * XXX FIXME 486 * XXX This algorithm is a hack. But I don't know any 487 * XXX better solution for now... 488 */ 489 SYSCTL_WLOCK(); 490 TAILQ_FOREACH(e, clist, link) { 491 error = sysctl_remove_oid_locked(e->entry, 0, 0); 492 if (error) 493 break; 494 } 495 /* 496 * Restore deregistered entries, either from the end, 497 * or from the place where error occurred. 498 * e contains the entry that was not unregistered 499 */ 500 if (error) 501 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 502 else 503 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 504 while (e1 != NULL) { 505 sysctl_register_oid(e1->entry); 506 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 507 } 508 if (error) { 509 SYSCTL_WUNLOCK(); 510 return(EBUSY); 511 } 512 /* Now really delete the entries */ 513 e = TAILQ_FIRST(clist); 514 while (e != NULL) { 515 e1 = TAILQ_NEXT(e, link); 516 error = sysctl_remove_oid_locked(e->entry, 1, 0); 517 if (error) 518 panic("sysctl_remove_oid: corrupt tree, entry: %s", 519 e->entry->oid_name); 520 free(e, M_SYSCTLOID); 521 e = e1; 522 } 523 SYSCTL_WUNLOCK(); 524 return (error); 525 } 526 527 /* Add an entry to the context */ 528 struct sysctl_ctx_entry * 529 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 530 { 531 struct sysctl_ctx_entry *e; 532 533 SYSCTL_ASSERT_WLOCKED(); 534 if (clist == NULL || oidp == NULL) 535 return(NULL); 536 e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 537 e->entry = oidp; 538 TAILQ_INSERT_HEAD(clist, e, link); 539 return (e); 540 } 541 542 /* Find an entry in the context */ 543 struct sysctl_ctx_entry * 544 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 545 { 546 struct sysctl_ctx_entry *e; 547 548 SYSCTL_ASSERT_WLOCKED(); 549 if (clist == NULL || oidp == NULL) 550 return(NULL); 551 TAILQ_FOREACH(e, clist, link) { 552 if(e->entry == oidp) 553 return(e); 554 } 555 return (e); 556 } 557 558 /* 559 * Delete an entry from the context. 560 * NOTE: this function doesn't free oidp! You have to remove it 561 * with sysctl_remove_oid(). 562 */ 563 int 564 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 565 { 566 struct sysctl_ctx_entry *e; 567 568 if (clist == NULL || oidp == NULL) 569 return (EINVAL); 570 SYSCTL_WLOCK(); 571 e = sysctl_ctx_entry_find(clist, oidp); 572 if (e != NULL) { 573 TAILQ_REMOVE(clist, e, link); 574 SYSCTL_WUNLOCK(); 575 free(e, M_SYSCTLOID); 576 return (0); 577 } else { 578 SYSCTL_WUNLOCK(); 579 return (ENOENT); 580 } 581 } 582 583 /* 584 * Remove dynamically created sysctl trees. 585 * oidp - top of the tree to be removed 586 * del - if 0 - just deregister, otherwise free up entries as well 587 * recurse - if != 0 traverse the subtree to be deleted 588 */ 589 int 590 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 591 { 592 int error; 593 594 SYSCTL_WLOCK(); 595 error = sysctl_remove_oid_locked(oidp, del, recurse); 596 SYSCTL_WUNLOCK(); 597 return (error); 598 } 599 600 int 601 sysctl_remove_name(struct sysctl_oid *parent, const char *name, 602 int del, int recurse) 603 { 604 struct sysctl_oid *p, *tmp; 605 int error; 606 607 error = ENOENT; 608 SYSCTL_WLOCK(); 609 SLIST_FOREACH_SAFE(p, SYSCTL_CHILDREN(parent), oid_link, tmp) { 610 if (strcmp(p->oid_name, name) == 0) { 611 error = sysctl_remove_oid_locked(p, del, recurse); 612 break; 613 } 614 } 615 SYSCTL_WUNLOCK(); 616 617 return (error); 618 } 619 620 621 static int 622 sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse) 623 { 624 struct sysctl_oid *p, *tmp; 625 int error; 626 627 SYSCTL_ASSERT_WLOCKED(); 628 if (oidp == NULL) 629 return(EINVAL); 630 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 631 printf("Warning: can't remove non-dynamic nodes (%s)!\n", 632 oidp->oid_name); 633 return (EINVAL); 634 } 635 /* 636 * WARNING: normal method to do this should be through 637 * sysctl_ctx_free(). Use recursing as the last resort 638 * method to purge your sysctl tree of leftovers... 639 * However, if some other code still references these nodes, 640 * it will panic. 641 */ 642 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 643 if (oidp->oid_refcnt == 1) { 644 SLIST_FOREACH_SAFE(p, 645 SYSCTL_CHILDREN(oidp), oid_link, tmp) { 646 if (!recurse) { 647 printf("Warning: failed attempt to " 648 "remove oid %s with child %s\n", 649 oidp->oid_name, p->oid_name); 650 return (ENOTEMPTY); 651 } 652 error = sysctl_remove_oid_locked(p, del, 653 recurse); 654 if (error) 655 return (error); 656 } 657 } 658 } 659 if (oidp->oid_refcnt > 1 ) { 660 oidp->oid_refcnt--; 661 } else { 662 if (oidp->oid_refcnt == 0) { 663 printf("Warning: bad oid_refcnt=%u (%s)!\n", 664 oidp->oid_refcnt, oidp->oid_name); 665 return (EINVAL); 666 } 667 sysctl_unregister_oid(oidp); 668 if (del) { 669 /* 670 * Wait for all threads running the handler to drain. 671 * This preserves the previous behavior when the 672 * sysctl lock was held across a handler invocation, 673 * and is necessary for module unload correctness. 674 */ 675 while (oidp->oid_running > 0) { 676 oidp->oid_kind |= CTLFLAG_DYING; 677 SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0); 678 } 679 if (oidp->oid_descr) 680 free(__DECONST(char *, oidp->oid_descr), 681 M_SYSCTLOID); 682 if (oidp->oid_label) 683 free(__DECONST(char *, oidp->oid_label), 684 M_SYSCTLOID); 685 free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); 686 free(oidp, M_SYSCTLOID); 687 } 688 } 689 return (0); 690 } 691 /* 692 * Create new sysctls at run time. 693 * clist may point to a valid context initialized with sysctl_ctx_init(). 694 */ 695 struct sysctl_oid * 696 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 697 int number, const char *name, int kind, void *arg1, intmax_t arg2, 698 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr, 699 const char *label) 700 { 701 struct sysctl_oid *oidp; 702 703 /* You have to hook up somewhere.. */ 704 if (parent == NULL) 705 return(NULL); 706 /* Check if the node already exists, otherwise create it */ 707 SYSCTL_WLOCK(); 708 oidp = sysctl_find_oidname(name, parent); 709 if (oidp != NULL) { 710 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 711 oidp->oid_refcnt++; 712 /* Update the context */ 713 if (clist != NULL) 714 sysctl_ctx_entry_add(clist, oidp); 715 SYSCTL_WUNLOCK(); 716 return (oidp); 717 } else { 718 SYSCTL_WUNLOCK(); 719 printf("can't re-use a leaf (%s)!\n", name); 720 return (NULL); 721 } 722 } 723 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO); 724 oidp->oid_parent = parent; 725 SLIST_INIT(&oidp->oid_children); 726 oidp->oid_number = number; 727 oidp->oid_refcnt = 1; 728 oidp->oid_name = strdup(name, M_SYSCTLOID); 729 oidp->oid_handler = handler; 730 oidp->oid_kind = CTLFLAG_DYN | kind; 731 oidp->oid_arg1 = arg1; 732 oidp->oid_arg2 = arg2; 733 oidp->oid_fmt = fmt; 734 if (descr != NULL) 735 oidp->oid_descr = strdup(descr, M_SYSCTLOID); 736 if (label != NULL) 737 oidp->oid_label = strdup(label, M_SYSCTLOID); 738 /* Update the context, if used */ 739 if (clist != NULL) 740 sysctl_ctx_entry_add(clist, oidp); 741 /* Register this oid */ 742 sysctl_register_oid(oidp); 743 SYSCTL_WUNLOCK(); 744 return (oidp); 745 } 746 747 /* 748 * Rename an existing oid. 749 */ 750 void 751 sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) 752 { 753 char *newname; 754 char *oldname; 755 756 newname = strdup(name, M_SYSCTLOID); 757 SYSCTL_WLOCK(); 758 oldname = __DECONST(char *, oidp->oid_name); 759 oidp->oid_name = newname; 760 SYSCTL_WUNLOCK(); 761 free(oldname, M_SYSCTLOID); 762 } 763 764 /* 765 * Reparent an existing oid. 766 */ 767 int 768 sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent) 769 { 770 struct sysctl_oid *oidp; 771 772 SYSCTL_WLOCK(); 773 if (oid->oid_parent == parent) { 774 SYSCTL_WUNLOCK(); 775 return (0); 776 } 777 oidp = sysctl_find_oidname(oid->oid_name, parent); 778 if (oidp != NULL) { 779 SYSCTL_WUNLOCK(); 780 return (EEXIST); 781 } 782 sysctl_unregister_oid(oid); 783 oid->oid_parent = parent; 784 oid->oid_number = OID_AUTO; 785 sysctl_register_oid(oid); 786 SYSCTL_WUNLOCK(); 787 return (0); 788 } 789 790 /* 791 * Register the kernel's oids on startup. 792 */ 793 SET_DECLARE(sysctl_set, struct sysctl_oid); 794 795 static void 796 sysctl_register_all(void *arg) 797 { 798 struct sysctl_oid **oidp; 799 800 sx_init(&sysctlmemlock, "sysctl mem"); 801 SYSCTL_INIT(); 802 SYSCTL_WLOCK(); 803 SET_FOREACH(oidp, sysctl_set) 804 sysctl_register_oid(*oidp); 805 SYSCTL_WUNLOCK(); 806 } 807 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, 0); 808 809 /* 810 * "Staff-functions" 811 * 812 * These functions implement a presently undocumented interface 813 * used by the sysctl program to walk the tree, and get the type 814 * so it can print the value. 815 * This interface is under work and consideration, and should probably 816 * be killed with a big axe by the first person who can find the time. 817 * (be aware though, that the proper interface isn't as obvious as it 818 * may seem, there are various conflicting requirements. 819 * 820 * {0,0} printf the entire MIB-tree. 821 * {0,1,...} return the name of the "..." OID. 822 * {0,2,...} return the next OID. 823 * {0,3} return the OID of the name in "new" 824 * {0,4,...} return the kind & format info for the "..." OID. 825 * {0,5,...} return the description of the "..." OID. 826 * {0,6,...} return the aggregation label of the "..." OID. 827 */ 828 829 #ifdef SYSCTL_DEBUG 830 static void 831 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 832 { 833 int k; 834 struct sysctl_oid *oidp; 835 836 SYSCTL_ASSERT_LOCKED(); 837 SLIST_FOREACH(oidp, l, oid_link) { 838 839 for (k=0; k<i; k++) 840 printf(" "); 841 842 printf("%d %s ", oidp->oid_number, oidp->oid_name); 843 844 printf("%c%c", 845 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 846 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 847 848 if (oidp->oid_handler) 849 printf(" *Handler"); 850 851 switch (oidp->oid_kind & CTLTYPE) { 852 case CTLTYPE_NODE: 853 printf(" Node\n"); 854 if (!oidp->oid_handler) { 855 sysctl_sysctl_debug_dump_node( 856 SYSCTL_CHILDREN(oidp), i + 2); 857 } 858 break; 859 case CTLTYPE_INT: printf(" Int\n"); break; 860 case CTLTYPE_UINT: printf(" u_int\n"); break; 861 case CTLTYPE_LONG: printf(" Long\n"); break; 862 case CTLTYPE_ULONG: printf(" u_long\n"); break; 863 case CTLTYPE_STRING: printf(" String\n"); break; 864 case CTLTYPE_S8: printf(" int8_t\n"); break; 865 case CTLTYPE_S16: printf(" int16_t\n"); break; 866 case CTLTYPE_S32: printf(" int32_t\n"); break; 867 case CTLTYPE_S64: printf(" int64_t\n"); break; 868 case CTLTYPE_U8: printf(" uint8_t\n"); break; 869 case CTLTYPE_U16: printf(" uint16_t\n"); break; 870 case CTLTYPE_U32: printf(" uint32_t\n"); break; 871 case CTLTYPE_U64: printf(" uint64_t\n"); break; 872 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; 873 default: printf("\n"); 874 } 875 876 } 877 } 878 879 static int 880 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 881 { 882 struct rm_priotracker tracker; 883 int error; 884 885 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 886 if (error) 887 return (error); 888 SYSCTL_RLOCK(&tracker); 889 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 890 SYSCTL_RUNLOCK(&tracker); 891 return (ENOENT); 892 } 893 894 SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD|CTLFLAG_MPSAFE, 895 0, 0, sysctl_sysctl_debug, "-", ""); 896 #endif 897 898 static int 899 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 900 { 901 int *name = (int *) arg1; 902 u_int namelen = arg2; 903 int error = 0; 904 struct sysctl_oid *oid; 905 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 906 struct rm_priotracker tracker; 907 char buf[10]; 908 909 SYSCTL_RLOCK(&tracker); 910 while (namelen) { 911 if (!lsp) { 912 snprintf(buf,sizeof(buf),"%d",*name); 913 if (req->oldidx) 914 error = SYSCTL_OUT(req, ".", 1); 915 if (!error) 916 error = SYSCTL_OUT(req, buf, strlen(buf)); 917 if (error) 918 goto out; 919 namelen--; 920 name++; 921 continue; 922 } 923 lsp2 = NULL; 924 SLIST_FOREACH(oid, lsp, oid_link) { 925 if (oid->oid_number != *name) 926 continue; 927 928 if (req->oldidx) 929 error = SYSCTL_OUT(req, ".", 1); 930 if (!error) 931 error = SYSCTL_OUT(req, oid->oid_name, 932 strlen(oid->oid_name)); 933 if (error) 934 goto out; 935 936 namelen--; 937 name++; 938 939 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 940 break; 941 942 if (oid->oid_handler) 943 break; 944 945 lsp2 = SYSCTL_CHILDREN(oid); 946 break; 947 } 948 lsp = lsp2; 949 } 950 error = SYSCTL_OUT(req, "", 1); 951 out: 952 SYSCTL_RUNLOCK(&tracker); 953 return (error); 954 } 955 956 /* 957 * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in 958 * capability mode. 959 */ 960 static SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, 961 sysctl_sysctl_name, ""); 962 963 static int 964 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 965 int *next, int *len, int level, struct sysctl_oid **oidpp) 966 { 967 struct sysctl_oid *oidp; 968 969 SYSCTL_ASSERT_LOCKED(); 970 *len = level; 971 SLIST_FOREACH(oidp, lsp, oid_link) { 972 *next = oidp->oid_number; 973 *oidpp = oidp; 974 975 if (oidp->oid_kind & CTLFLAG_SKIP) 976 continue; 977 978 if (!namelen) { 979 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 980 return (0); 981 if (oidp->oid_handler) 982 /* We really should call the handler here...*/ 983 return (0); 984 lsp = SYSCTL_CHILDREN(oidp); 985 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 986 len, level+1, oidpp)) 987 return (0); 988 goto emptynode; 989 } 990 991 if (oidp->oid_number < *name) 992 continue; 993 994 if (oidp->oid_number > *name) { 995 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 996 return (0); 997 if (oidp->oid_handler) 998 return (0); 999 lsp = SYSCTL_CHILDREN(oidp); 1000 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 1001 next+1, len, level+1, oidpp)) 1002 return (0); 1003 goto next; 1004 } 1005 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1006 continue; 1007 1008 if (oidp->oid_handler) 1009 continue; 1010 1011 lsp = SYSCTL_CHILDREN(oidp); 1012 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 1013 len, level+1, oidpp)) 1014 return (0); 1015 next: 1016 namelen = 1; 1017 emptynode: 1018 *len = level; 1019 } 1020 return (1); 1021 } 1022 1023 static int 1024 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 1025 { 1026 int *name = (int *) arg1; 1027 u_int namelen = arg2; 1028 int i, j, error; 1029 struct sysctl_oid *oid; 1030 struct sysctl_oid_list *lsp = &sysctl__children; 1031 struct rm_priotracker tracker; 1032 int newoid[CTL_MAXNAME]; 1033 1034 SYSCTL_RLOCK(&tracker); 1035 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 1036 SYSCTL_RUNLOCK(&tracker); 1037 if (i) 1038 return (ENOENT); 1039 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 1040 return (error); 1041 } 1042 1043 /* 1044 * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in 1045 * capability mode. 1046 */ 1047 static SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, 1048 sysctl_sysctl_next, ""); 1049 1050 static int 1051 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) 1052 { 1053 struct sysctl_oid *oidp; 1054 struct sysctl_oid_list *lsp = &sysctl__children; 1055 char *p; 1056 1057 SYSCTL_ASSERT_LOCKED(); 1058 1059 for (*len = 0; *len < CTL_MAXNAME;) { 1060 p = strsep(&name, "."); 1061 1062 oidp = SLIST_FIRST(lsp); 1063 for (;; oidp = SLIST_NEXT(oidp, oid_link)) { 1064 if (oidp == NULL) 1065 return (ENOENT); 1066 if (strcmp(p, oidp->oid_name) == 0) 1067 break; 1068 } 1069 *oid++ = oidp->oid_number; 1070 (*len)++; 1071 1072 if (name == NULL || *name == '\0') { 1073 if (oidpp) 1074 *oidpp = oidp; 1075 return (0); 1076 } 1077 1078 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1079 break; 1080 1081 if (oidp->oid_handler) 1082 break; 1083 1084 lsp = SYSCTL_CHILDREN(oidp); 1085 } 1086 return (ENOENT); 1087 } 1088 1089 static int 1090 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 1091 { 1092 char *p; 1093 int error, oid[CTL_MAXNAME], len = 0; 1094 struct sysctl_oid *op = NULL; 1095 struct rm_priotracker tracker; 1096 1097 if (!req->newlen) 1098 return (ENOENT); 1099 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 1100 return (ENAMETOOLONG); 1101 1102 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); 1103 1104 error = SYSCTL_IN(req, p, req->newlen); 1105 if (error) { 1106 free(p, M_SYSCTL); 1107 return (error); 1108 } 1109 1110 p [req->newlen] = '\0'; 1111 1112 SYSCTL_RLOCK(&tracker); 1113 error = name2oid(p, oid, &len, &op); 1114 SYSCTL_RUNLOCK(&tracker); 1115 1116 free(p, M_SYSCTL); 1117 1118 if (error) 1119 return (error); 1120 1121 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 1122 return (error); 1123 } 1124 1125 /* 1126 * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in 1127 * capability mode. 1128 */ 1129 SYSCTL_PROC(_sysctl, 3, name2oid, 1130 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_ANYBODY | CTLFLAG_MPSAFE 1131 | CTLFLAG_CAPRW, 0, 0, sysctl_sysctl_name2oid, "I", ""); 1132 1133 static int 1134 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 1135 { 1136 struct sysctl_oid *oid; 1137 struct rm_priotracker tracker; 1138 int error; 1139 1140 SYSCTL_RLOCK(&tracker); 1141 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1142 if (error) 1143 goto out; 1144 1145 if (oid->oid_fmt == NULL) { 1146 error = ENOENT; 1147 goto out; 1148 } 1149 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 1150 if (error) 1151 goto out; 1152 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 1153 out: 1154 SYSCTL_RUNLOCK(&tracker); 1155 return (error); 1156 } 1157 1158 1159 static SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLFLAG_CAPRD, 1160 sysctl_sysctl_oidfmt, ""); 1161 1162 static int 1163 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 1164 { 1165 struct sysctl_oid *oid; 1166 struct rm_priotracker tracker; 1167 int error; 1168 1169 SYSCTL_RLOCK(&tracker); 1170 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1171 if (error) 1172 goto out; 1173 1174 if (oid->oid_descr == NULL) { 1175 error = ENOENT; 1176 goto out; 1177 } 1178 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 1179 out: 1180 SYSCTL_RUNLOCK(&tracker); 1181 return (error); 1182 } 1183 1184 static SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLFLAG_CAPRD, 1185 sysctl_sysctl_oiddescr, ""); 1186 1187 static int 1188 sysctl_sysctl_oidlabel(SYSCTL_HANDLER_ARGS) 1189 { 1190 struct sysctl_oid *oid; 1191 struct rm_priotracker tracker; 1192 int error; 1193 1194 SYSCTL_RLOCK(&tracker); 1195 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1196 if (error) 1197 goto out; 1198 1199 if (oid->oid_label == NULL) { 1200 error = ENOENT; 1201 goto out; 1202 } 1203 error = SYSCTL_OUT(req, oid->oid_label, strlen(oid->oid_label) + 1); 1204 out: 1205 SYSCTL_RUNLOCK(&tracker); 1206 return (error); 1207 } 1208 1209 static SYSCTL_NODE(_sysctl, 6, oidlabel, 1210 CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidlabel, ""); 1211 1212 /* 1213 * Default "handler" functions. 1214 */ 1215 1216 /* 1217 * Handle a bool. 1218 * Two cases: 1219 * a variable: point arg1 at it. 1220 * a constant: pass it in arg2. 1221 */ 1222 1223 int 1224 sysctl_handle_bool(SYSCTL_HANDLER_ARGS) 1225 { 1226 uint8_t temp; 1227 int error; 1228 1229 /* 1230 * Attempt to get a coherent snapshot by making a copy of the data. 1231 */ 1232 if (arg1) 1233 temp = *(bool *)arg1 ? 1 : 0; 1234 else 1235 temp = arg2 ? 1 : 0; 1236 1237 error = SYSCTL_OUT(req, &temp, sizeof(temp)); 1238 if (error || !req->newptr) 1239 return (error); 1240 1241 if (!arg1) 1242 error = EPERM; 1243 else { 1244 error = SYSCTL_IN(req, &temp, sizeof(temp)); 1245 if (!error) 1246 *(bool *)arg1 = temp ? 1 : 0; 1247 } 1248 return (error); 1249 } 1250 1251 /* 1252 * Handle an int8_t, signed or unsigned. 1253 * Two cases: 1254 * a variable: point arg1 at it. 1255 * a constant: pass it in arg2. 1256 */ 1257 1258 int 1259 sysctl_handle_8(SYSCTL_HANDLER_ARGS) 1260 { 1261 int8_t tmpout; 1262 int error = 0; 1263 1264 /* 1265 * Attempt to get a coherent snapshot by making a copy of the data. 1266 */ 1267 if (arg1) 1268 tmpout = *(int8_t *)arg1; 1269 else 1270 tmpout = arg2; 1271 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1272 1273 if (error || !req->newptr) 1274 return (error); 1275 1276 if (!arg1) 1277 error = EPERM; 1278 else 1279 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1280 return (error); 1281 } 1282 1283 /* 1284 * Handle an int16_t, signed or unsigned. 1285 * Two cases: 1286 * a variable: point arg1 at it. 1287 * a constant: pass it in arg2. 1288 */ 1289 1290 int 1291 sysctl_handle_16(SYSCTL_HANDLER_ARGS) 1292 { 1293 int16_t tmpout; 1294 int error = 0; 1295 1296 /* 1297 * Attempt to get a coherent snapshot by making a copy of the data. 1298 */ 1299 if (arg1) 1300 tmpout = *(int16_t *)arg1; 1301 else 1302 tmpout = arg2; 1303 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1304 1305 if (error || !req->newptr) 1306 return (error); 1307 1308 if (!arg1) 1309 error = EPERM; 1310 else 1311 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1312 return (error); 1313 } 1314 1315 /* 1316 * Handle an int32_t, signed or unsigned. 1317 * Two cases: 1318 * a variable: point arg1 at it. 1319 * a constant: pass it in arg2. 1320 */ 1321 1322 int 1323 sysctl_handle_32(SYSCTL_HANDLER_ARGS) 1324 { 1325 int32_t tmpout; 1326 int error = 0; 1327 1328 /* 1329 * Attempt to get a coherent snapshot by making a copy of the data. 1330 */ 1331 if (arg1) 1332 tmpout = *(int32_t *)arg1; 1333 else 1334 tmpout = arg2; 1335 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1336 1337 if (error || !req->newptr) 1338 return (error); 1339 1340 if (!arg1) 1341 error = EPERM; 1342 else 1343 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1344 return (error); 1345 } 1346 1347 /* 1348 * Handle an int, signed or unsigned. 1349 * Two cases: 1350 * a variable: point arg1 at it. 1351 * a constant: pass it in arg2. 1352 */ 1353 1354 int 1355 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 1356 { 1357 int tmpout, error = 0; 1358 1359 /* 1360 * Attempt to get a coherent snapshot by making a copy of the data. 1361 */ 1362 if (arg1) 1363 tmpout = *(int *)arg1; 1364 else 1365 tmpout = arg2; 1366 error = SYSCTL_OUT(req, &tmpout, sizeof(int)); 1367 1368 if (error || !req->newptr) 1369 return (error); 1370 1371 if (!arg1) 1372 error = EPERM; 1373 else 1374 error = SYSCTL_IN(req, arg1, sizeof(int)); 1375 return (error); 1376 } 1377 1378 /* 1379 * Based on on sysctl_handle_int() convert milliseconds into ticks. 1380 * Note: this is used by TCP. 1381 */ 1382 1383 int 1384 sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) 1385 { 1386 int error, s, tt; 1387 1388 tt = *(int *)arg1; 1389 s = (int)((int64_t)tt * 1000 / hz); 1390 1391 error = sysctl_handle_int(oidp, &s, 0, req); 1392 if (error || !req->newptr) 1393 return (error); 1394 1395 tt = (int)((int64_t)s * hz / 1000); 1396 if (tt < 1) 1397 return (EINVAL); 1398 1399 *(int *)arg1 = tt; 1400 return (0); 1401 } 1402 1403 1404 /* 1405 * Handle a long, signed or unsigned. 1406 * Two cases: 1407 * a variable: point arg1 at it. 1408 * a constant: pass it in arg2. 1409 */ 1410 1411 int 1412 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 1413 { 1414 int error = 0; 1415 long tmplong; 1416 #ifdef SCTL_MASK32 1417 int tmpint; 1418 #endif 1419 1420 /* 1421 * Attempt to get a coherent snapshot by making a copy of the data. 1422 */ 1423 if (arg1) 1424 tmplong = *(long *)arg1; 1425 else 1426 tmplong = arg2; 1427 #ifdef SCTL_MASK32 1428 if (req->flags & SCTL_MASK32) { 1429 tmpint = tmplong; 1430 error = SYSCTL_OUT(req, &tmpint, sizeof(int)); 1431 } else 1432 #endif 1433 error = SYSCTL_OUT(req, &tmplong, sizeof(long)); 1434 1435 if (error || !req->newptr) 1436 return (error); 1437 1438 if (!arg1) 1439 error = EPERM; 1440 #ifdef SCTL_MASK32 1441 else if (req->flags & SCTL_MASK32) { 1442 error = SYSCTL_IN(req, &tmpint, sizeof(int)); 1443 *(long *)arg1 = (long)tmpint; 1444 } 1445 #endif 1446 else 1447 error = SYSCTL_IN(req, arg1, sizeof(long)); 1448 return (error); 1449 } 1450 1451 /* 1452 * Handle a 64 bit int, signed or unsigned. 1453 * Two cases: 1454 * a variable: point arg1 at it. 1455 * a constant: pass it in arg2. 1456 */ 1457 int 1458 sysctl_handle_64(SYSCTL_HANDLER_ARGS) 1459 { 1460 int error = 0; 1461 uint64_t tmpout; 1462 1463 /* 1464 * Attempt to get a coherent snapshot by making a copy of the data. 1465 */ 1466 if (arg1) 1467 tmpout = *(uint64_t *)arg1; 1468 else 1469 tmpout = arg2; 1470 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t)); 1471 1472 if (error || !req->newptr) 1473 return (error); 1474 1475 if (!arg1) 1476 error = EPERM; 1477 else 1478 error = SYSCTL_IN(req, arg1, sizeof(uint64_t)); 1479 return (error); 1480 } 1481 1482 /* 1483 * Handle our generic '\0' terminated 'C' string. 1484 * Two cases: 1485 * a variable string: point arg1 at it, arg2 is max length. 1486 * a constant string: point arg1 at it, arg2 is zero. 1487 */ 1488 1489 int 1490 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 1491 { 1492 size_t outlen; 1493 int error = 0, ro_string = 0; 1494 1495 /* 1496 * A zero-length buffer indicates a fixed size read-only 1497 * string: 1498 */ 1499 if (arg2 == 0) { 1500 arg2 = strlen((char *)arg1) + 1; 1501 ro_string = 1; 1502 } 1503 1504 if (req->oldptr != NULL) { 1505 char *tmparg; 1506 1507 if (ro_string) { 1508 tmparg = arg1; 1509 } else { 1510 /* try to make a coherent snapshot of the string */ 1511 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1512 memcpy(tmparg, arg1, arg2); 1513 } 1514 1515 outlen = strnlen(tmparg, arg2 - 1) + 1; 1516 error = SYSCTL_OUT(req, tmparg, outlen); 1517 1518 if (!ro_string) 1519 free(tmparg, M_SYSCTLTMP); 1520 } else { 1521 outlen = strnlen((char *)arg1, arg2 - 1) + 1; 1522 error = SYSCTL_OUT(req, NULL, outlen); 1523 } 1524 if (error || !req->newptr) 1525 return (error); 1526 1527 if ((req->newlen - req->newidx) >= arg2) { 1528 error = EINVAL; 1529 } else { 1530 arg2 = (req->newlen - req->newidx); 1531 error = SYSCTL_IN(req, arg1, arg2); 1532 ((char *)arg1)[arg2] = '\0'; 1533 } 1534 return (error); 1535 } 1536 1537 /* 1538 * Handle any kind of opaque data. 1539 * arg1 points to it, arg2 is the size. 1540 */ 1541 1542 int 1543 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 1544 { 1545 int error, tries; 1546 u_int generation; 1547 struct sysctl_req req2; 1548 1549 /* 1550 * Attempt to get a coherent snapshot, by using the thread 1551 * pre-emption counter updated from within mi_switch() to 1552 * determine if we were pre-empted during a bcopy() or 1553 * copyout(). Make 3 attempts at doing this before giving up. 1554 * If we encounter an error, stop immediately. 1555 */ 1556 tries = 0; 1557 req2 = *req; 1558 retry: 1559 generation = curthread->td_generation; 1560 error = SYSCTL_OUT(req, arg1, arg2); 1561 if (error) 1562 return (error); 1563 tries++; 1564 if (generation != curthread->td_generation && tries < 3) { 1565 *req = req2; 1566 goto retry; 1567 } 1568 1569 error = SYSCTL_IN(req, arg1, arg2); 1570 1571 return (error); 1572 } 1573 1574 /* 1575 * Transfer functions to/from kernel space. 1576 * XXX: rather untested at this point 1577 */ 1578 static int 1579 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 1580 { 1581 size_t i = 0; 1582 1583 if (req->oldptr) { 1584 i = l; 1585 if (req->oldlen <= req->oldidx) 1586 i = 0; 1587 else 1588 if (i > req->oldlen - req->oldidx) 1589 i = req->oldlen - req->oldidx; 1590 if (i > 0) 1591 bcopy(p, (char *)req->oldptr + req->oldidx, i); 1592 } 1593 req->oldidx += l; 1594 if (req->oldptr && i != l) 1595 return (ENOMEM); 1596 return (0); 1597 } 1598 1599 static int 1600 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 1601 { 1602 if (!req->newptr) 1603 return (0); 1604 if (req->newlen - req->newidx < l) 1605 return (EINVAL); 1606 bcopy((char *)req->newptr + req->newidx, p, l); 1607 req->newidx += l; 1608 return (0); 1609 } 1610 1611 int 1612 kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1613 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) 1614 { 1615 int error = 0; 1616 struct sysctl_req req; 1617 1618 bzero(&req, sizeof req); 1619 1620 req.td = td; 1621 req.flags = flags; 1622 1623 if (oldlenp) { 1624 req.oldlen = *oldlenp; 1625 } 1626 req.validlen = req.oldlen; 1627 1628 if (old) { 1629 req.oldptr= old; 1630 } 1631 1632 if (new != NULL) { 1633 req.newlen = newlen; 1634 req.newptr = new; 1635 } 1636 1637 req.oldfunc = sysctl_old_kernel; 1638 req.newfunc = sysctl_new_kernel; 1639 req.lock = REQ_UNWIRED; 1640 1641 error = sysctl_root(0, name, namelen, &req); 1642 1643 if (req.lock == REQ_WIRED && req.validlen > 0) 1644 vsunlock(req.oldptr, req.validlen); 1645 1646 if (error && error != ENOMEM) 1647 return (error); 1648 1649 if (retval) { 1650 if (req.oldptr && req.oldidx > req.validlen) 1651 *retval = req.validlen; 1652 else 1653 *retval = req.oldidx; 1654 } 1655 return (error); 1656 } 1657 1658 int 1659 kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp, 1660 void *new, size_t newlen, size_t *retval, int flags) 1661 { 1662 int oid[CTL_MAXNAME]; 1663 size_t oidlen, plen; 1664 int error; 1665 1666 oid[0] = 0; /* sysctl internal magic */ 1667 oid[1] = 3; /* name2oid */ 1668 oidlen = sizeof(oid); 1669 1670 error = kernel_sysctl(td, oid, 2, oid, &oidlen, 1671 (void *)name, strlen(name), &plen, flags); 1672 if (error) 1673 return (error); 1674 1675 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp, 1676 new, newlen, retval, flags); 1677 return (error); 1678 } 1679 1680 /* 1681 * Transfer function to/from user space. 1682 */ 1683 static int 1684 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1685 { 1686 size_t i, len, origidx; 1687 int error; 1688 1689 origidx = req->oldidx; 1690 req->oldidx += l; 1691 if (req->oldptr == NULL) 1692 return (0); 1693 /* 1694 * If we have not wired the user supplied buffer and we are currently 1695 * holding locks, drop a witness warning, as it's possible that 1696 * write operations to the user page can sleep. 1697 */ 1698 if (req->lock != REQ_WIRED) 1699 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1700 "sysctl_old_user()"); 1701 i = l; 1702 len = req->validlen; 1703 if (len <= origidx) 1704 i = 0; 1705 else { 1706 if (i > len - origidx) 1707 i = len - origidx; 1708 if (req->lock == REQ_WIRED) { 1709 error = copyout_nofault(p, (char *)req->oldptr + 1710 origidx, i); 1711 } else 1712 error = copyout(p, (char *)req->oldptr + origidx, i); 1713 if (error != 0) 1714 return (error); 1715 } 1716 if (i < l) 1717 return (ENOMEM); 1718 return (0); 1719 } 1720 1721 static int 1722 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1723 { 1724 int error; 1725 1726 if (!req->newptr) 1727 return (0); 1728 if (req->newlen - req->newidx < l) 1729 return (EINVAL); 1730 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1731 "sysctl_new_user()"); 1732 error = copyin((char *)req->newptr + req->newidx, p, l); 1733 req->newidx += l; 1734 return (error); 1735 } 1736 1737 /* 1738 * Wire the user space destination buffer. If set to a value greater than 1739 * zero, the len parameter limits the maximum amount of wired memory. 1740 */ 1741 int 1742 sysctl_wire_old_buffer(struct sysctl_req *req, size_t len) 1743 { 1744 int ret; 1745 size_t wiredlen; 1746 1747 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen; 1748 ret = 0; 1749 if (req->lock != REQ_WIRED && req->oldptr && 1750 req->oldfunc == sysctl_old_user) { 1751 if (wiredlen != 0) { 1752 ret = vslock(req->oldptr, wiredlen); 1753 if (ret != 0) { 1754 if (ret != ENOMEM) 1755 return (ret); 1756 wiredlen = 0; 1757 } 1758 } 1759 req->lock = REQ_WIRED; 1760 req->validlen = wiredlen; 1761 } 1762 return (0); 1763 } 1764 1765 int 1766 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 1767 int *nindx, struct sysctl_req *req) 1768 { 1769 struct sysctl_oid_list *lsp; 1770 struct sysctl_oid *oid; 1771 int indx; 1772 1773 SYSCTL_ASSERT_LOCKED(); 1774 lsp = &sysctl__children; 1775 indx = 0; 1776 while (indx < CTL_MAXNAME) { 1777 SLIST_FOREACH(oid, lsp, oid_link) { 1778 if (oid->oid_number == name[indx]) 1779 break; 1780 } 1781 if (oid == NULL) 1782 return (ENOENT); 1783 1784 indx++; 1785 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1786 if (oid->oid_handler != NULL || indx == namelen) { 1787 *noid = oid; 1788 if (nindx != NULL) 1789 *nindx = indx; 1790 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 1791 ("%s found DYING node %p", __func__, oid)); 1792 return (0); 1793 } 1794 lsp = SYSCTL_CHILDREN(oid); 1795 } else if (indx == namelen) { 1796 *noid = oid; 1797 if (nindx != NULL) 1798 *nindx = indx; 1799 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 1800 ("%s found DYING node %p", __func__, oid)); 1801 return (0); 1802 } else { 1803 return (ENOTDIR); 1804 } 1805 } 1806 return (ENOENT); 1807 } 1808 1809 /* 1810 * Traverse our tree, and find the right node, execute whatever it points 1811 * to, and return the resulting error code. 1812 */ 1813 1814 static int 1815 sysctl_root(SYSCTL_HANDLER_ARGS) 1816 { 1817 struct sysctl_oid *oid; 1818 struct rm_priotracker tracker; 1819 int error, indx, lvl; 1820 1821 SYSCTL_RLOCK(&tracker); 1822 1823 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 1824 if (error) 1825 goto out; 1826 1827 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1828 /* 1829 * You can't call a sysctl when it's a node, but has 1830 * no handler. Inform the user that it's a node. 1831 * The indx may or may not be the same as namelen. 1832 */ 1833 if (oid->oid_handler == NULL) { 1834 error = EISDIR; 1835 goto out; 1836 } 1837 } 1838 1839 /* Is this sysctl writable? */ 1840 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) { 1841 error = EPERM; 1842 goto out; 1843 } 1844 1845 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL")); 1846 1847 #ifdef CAPABILITY_MODE 1848 /* 1849 * If the process is in capability mode, then don't permit reading or 1850 * writing unless specifically granted for the node. 1851 */ 1852 if (IN_CAPABILITY_MODE(req->td)) { 1853 if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) || 1854 (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) { 1855 error = EPERM; 1856 goto out; 1857 } 1858 } 1859 #endif 1860 1861 /* Is this sysctl sensitive to securelevels? */ 1862 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) { 1863 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE; 1864 error = securelevel_gt(req->td->td_ucred, lvl); 1865 if (error) 1866 goto out; 1867 } 1868 1869 /* Is this sysctl writable by only privileged users? */ 1870 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) { 1871 int priv; 1872 1873 if (oid->oid_kind & CTLFLAG_PRISON) 1874 priv = PRIV_SYSCTL_WRITEJAIL; 1875 #ifdef VIMAGE 1876 else if ((oid->oid_kind & CTLFLAG_VNET) && 1877 prison_owns_vnet(req->td->td_ucred)) 1878 priv = PRIV_SYSCTL_WRITEJAIL; 1879 #endif 1880 else 1881 priv = PRIV_SYSCTL_WRITE; 1882 error = priv_check(req->td, priv); 1883 if (error) 1884 goto out; 1885 } 1886 1887 if (!oid->oid_handler) { 1888 error = EINVAL; 1889 goto out; 1890 } 1891 1892 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1893 arg1 = (int *)arg1 + indx; 1894 arg2 -= indx; 1895 } else { 1896 arg1 = oid->oid_arg1; 1897 arg2 = oid->oid_arg2; 1898 } 1899 #ifdef MAC 1900 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2, 1901 req); 1902 if (error != 0) 1903 goto out; 1904 #endif 1905 #ifdef VIMAGE 1906 if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL) 1907 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1); 1908 #endif 1909 error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker); 1910 1911 out: 1912 SYSCTL_RUNLOCK(&tracker); 1913 return (error); 1914 } 1915 1916 #ifndef _SYS_SYSPROTO_H_ 1917 struct sysctl_args { 1918 int *name; 1919 u_int namelen; 1920 void *old; 1921 size_t *oldlenp; 1922 void *new; 1923 size_t newlen; 1924 }; 1925 #endif 1926 int 1927 sys___sysctl(struct thread *td, struct sysctl_args *uap) 1928 { 1929 int error, i, name[CTL_MAXNAME]; 1930 size_t j; 1931 1932 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 1933 return (EINVAL); 1934 1935 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 1936 if (error) 1937 return (error); 1938 1939 error = userland_sysctl(td, name, uap->namelen, 1940 uap->old, uap->oldlenp, 0, 1941 uap->new, uap->newlen, &j, 0); 1942 if (error && error != ENOMEM) 1943 return (error); 1944 if (uap->oldlenp) { 1945 i = copyout(&j, uap->oldlenp, sizeof(j)); 1946 if (i) 1947 return (i); 1948 } 1949 return (error); 1950 } 1951 1952 /* 1953 * This is used from various compatibility syscalls too. That's why name 1954 * must be in kernel space. 1955 */ 1956 int 1957 userland_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1958 size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval, 1959 int flags) 1960 { 1961 int error = 0, memlocked; 1962 struct sysctl_req req; 1963 1964 bzero(&req, sizeof req); 1965 1966 req.td = td; 1967 req.flags = flags; 1968 1969 if (oldlenp) { 1970 if (inkernel) { 1971 req.oldlen = *oldlenp; 1972 } else { 1973 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 1974 if (error) 1975 return (error); 1976 } 1977 } 1978 req.validlen = req.oldlen; 1979 1980 if (old) { 1981 if (!useracc(old, req.oldlen, VM_PROT_WRITE)) 1982 return (EFAULT); 1983 req.oldptr= old; 1984 } 1985 1986 if (new != NULL) { 1987 if (!useracc(new, newlen, VM_PROT_READ)) 1988 return (EFAULT); 1989 req.newlen = newlen; 1990 req.newptr = new; 1991 } 1992 1993 req.oldfunc = sysctl_old_user; 1994 req.newfunc = sysctl_new_user; 1995 req.lock = REQ_UNWIRED; 1996 1997 #ifdef KTRACE 1998 if (KTRPOINT(curthread, KTR_SYSCTL)) 1999 ktrsysctl(name, namelen); 2000 #endif 2001 2002 if (req.oldptr && req.oldlen > PAGE_SIZE) { 2003 memlocked = 1; 2004 sx_xlock(&sysctlmemlock); 2005 } else 2006 memlocked = 0; 2007 CURVNET_SET(TD_TO_VNET(td)); 2008 2009 for (;;) { 2010 req.oldidx = 0; 2011 req.newidx = 0; 2012 error = sysctl_root(0, name, namelen, &req); 2013 if (error != EAGAIN) 2014 break; 2015 kern_yield(PRI_USER); 2016 } 2017 2018 CURVNET_RESTORE(); 2019 2020 if (req.lock == REQ_WIRED && req.validlen > 0) 2021 vsunlock(req.oldptr, req.validlen); 2022 if (memlocked) 2023 sx_xunlock(&sysctlmemlock); 2024 2025 if (error && error != ENOMEM) 2026 return (error); 2027 2028 if (retval) { 2029 if (req.oldptr && req.oldidx > req.validlen) 2030 *retval = req.validlen; 2031 else 2032 *retval = req.oldidx; 2033 } 2034 return (error); 2035 } 2036 2037 /* 2038 * Drain into a sysctl struct. The user buffer should be wired if a page 2039 * fault would cause issue. 2040 */ 2041 static int 2042 sbuf_sysctl_drain(void *arg, const char *data, int len) 2043 { 2044 struct sysctl_req *req = arg; 2045 int error; 2046 2047 error = SYSCTL_OUT(req, data, len); 2048 KASSERT(error >= 0, ("Got unexpected negative value %d", error)); 2049 return (error == 0 ? len : -error); 2050 } 2051 2052 struct sbuf * 2053 sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, 2054 struct sysctl_req *req) 2055 { 2056 2057 /* Supply a default buffer size if none given. */ 2058 if (buf == NULL && length == 0) 2059 length = 64; 2060 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL); 2061 sbuf_set_drain(s, sbuf_sysctl_drain, req); 2062 return (s); 2063 } 2064