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("can't remove non-dynamic nodes!\n"); 632 return (EINVAL); 633 } 634 /* 635 * WARNING: normal method to do this should be through 636 * sysctl_ctx_free(). Use recursing as the last resort 637 * method to purge your sysctl tree of leftovers... 638 * However, if some other code still references these nodes, 639 * it will panic. 640 */ 641 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 642 if (oidp->oid_refcnt == 1) { 643 SLIST_FOREACH_SAFE(p, 644 SYSCTL_CHILDREN(oidp), oid_link, tmp) { 645 if (!recurse) { 646 printf("Warning: failed attempt to " 647 "remove oid %s with child %s\n", 648 oidp->oid_name, p->oid_name); 649 return (ENOTEMPTY); 650 } 651 error = sysctl_remove_oid_locked(p, del, 652 recurse); 653 if (error) 654 return (error); 655 } 656 } 657 } 658 if (oidp->oid_refcnt > 1 ) { 659 oidp->oid_refcnt--; 660 } else { 661 if (oidp->oid_refcnt == 0) { 662 printf("Warning: bad oid_refcnt=%u (%s)!\n", 663 oidp->oid_refcnt, oidp->oid_name); 664 return (EINVAL); 665 } 666 sysctl_unregister_oid(oidp); 667 if (del) { 668 /* 669 * Wait for all threads running the handler to drain. 670 * This preserves the previous behavior when the 671 * sysctl lock was held across a handler invocation, 672 * and is necessary for module unload correctness. 673 */ 674 while (oidp->oid_running > 0) { 675 oidp->oid_kind |= CTLFLAG_DYING; 676 SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0); 677 } 678 if (oidp->oid_descr) 679 free(__DECONST(char *, oidp->oid_descr), 680 M_SYSCTLOID); 681 if (oidp->oid_label) 682 free(__DECONST(char *, oidp->oid_label), 683 M_SYSCTLOID); 684 free(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); 685 free(oidp, M_SYSCTLOID); 686 } 687 } 688 return (0); 689 } 690 /* 691 * Create new sysctls at run time. 692 * clist may point to a valid context initialized with sysctl_ctx_init(). 693 */ 694 struct sysctl_oid * 695 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 696 int number, const char *name, int kind, void *arg1, intmax_t arg2, 697 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr, 698 const char *label) 699 { 700 struct sysctl_oid *oidp; 701 702 /* You have to hook up somewhere.. */ 703 if (parent == NULL) 704 return(NULL); 705 /* Check if the node already exists, otherwise create it */ 706 SYSCTL_WLOCK(); 707 oidp = sysctl_find_oidname(name, parent); 708 if (oidp != NULL) { 709 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 710 oidp->oid_refcnt++; 711 /* Update the context */ 712 if (clist != NULL) 713 sysctl_ctx_entry_add(clist, oidp); 714 SYSCTL_WUNLOCK(); 715 return (oidp); 716 } else { 717 SYSCTL_WUNLOCK(); 718 printf("can't re-use a leaf (%s)!\n", name); 719 return (NULL); 720 } 721 } 722 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO); 723 oidp->oid_parent = parent; 724 SLIST_INIT(&oidp->oid_children); 725 oidp->oid_number = number; 726 oidp->oid_refcnt = 1; 727 oidp->oid_name = strdup(name, M_SYSCTLOID); 728 oidp->oid_handler = handler; 729 oidp->oid_kind = CTLFLAG_DYN | kind; 730 oidp->oid_arg1 = arg1; 731 oidp->oid_arg2 = arg2; 732 oidp->oid_fmt = fmt; 733 if (descr != NULL) 734 oidp->oid_descr = strdup(descr, M_SYSCTLOID); 735 if (label != NULL) 736 oidp->oid_label = strdup(label, M_SYSCTLOID); 737 /* Update the context, if used */ 738 if (clist != NULL) 739 sysctl_ctx_entry_add(clist, oidp); 740 /* Register this oid */ 741 sysctl_register_oid(oidp); 742 SYSCTL_WUNLOCK(); 743 return (oidp); 744 } 745 746 /* 747 * Rename an existing oid. 748 */ 749 void 750 sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) 751 { 752 char *newname; 753 char *oldname; 754 755 newname = strdup(name, M_SYSCTLOID); 756 SYSCTL_WLOCK(); 757 oldname = __DECONST(char *, oidp->oid_name); 758 oidp->oid_name = newname; 759 SYSCTL_WUNLOCK(); 760 free(oldname, M_SYSCTLOID); 761 } 762 763 /* 764 * Reparent an existing oid. 765 */ 766 int 767 sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent) 768 { 769 struct sysctl_oid *oidp; 770 771 SYSCTL_WLOCK(); 772 if (oid->oid_parent == parent) { 773 SYSCTL_WUNLOCK(); 774 return (0); 775 } 776 oidp = sysctl_find_oidname(oid->oid_name, parent); 777 if (oidp != NULL) { 778 SYSCTL_WUNLOCK(); 779 return (EEXIST); 780 } 781 sysctl_unregister_oid(oid); 782 oid->oid_parent = parent; 783 oid->oid_number = OID_AUTO; 784 sysctl_register_oid(oid); 785 SYSCTL_WUNLOCK(); 786 return (0); 787 } 788 789 /* 790 * Register the kernel's oids on startup. 791 */ 792 SET_DECLARE(sysctl_set, struct sysctl_oid); 793 794 static void 795 sysctl_register_all(void *arg) 796 { 797 struct sysctl_oid **oidp; 798 799 sx_init(&sysctlmemlock, "sysctl mem"); 800 SYSCTL_INIT(); 801 SYSCTL_WLOCK(); 802 SET_FOREACH(oidp, sysctl_set) 803 sysctl_register_oid(*oidp); 804 SYSCTL_WUNLOCK(); 805 } 806 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_FIRST, sysctl_register_all, 0); 807 808 /* 809 * "Staff-functions" 810 * 811 * These functions implement a presently undocumented interface 812 * used by the sysctl program to walk the tree, and get the type 813 * so it can print the value. 814 * This interface is under work and consideration, and should probably 815 * be killed with a big axe by the first person who can find the time. 816 * (be aware though, that the proper interface isn't as obvious as it 817 * may seem, there are various conflicting requirements. 818 * 819 * {0,0} printf the entire MIB-tree. 820 * {0,1,...} return the name of the "..." OID. 821 * {0,2,...} return the next OID. 822 * {0,3} return the OID of the name in "new" 823 * {0,4,...} return the kind & format info for the "..." OID. 824 * {0,5,...} return the description of the "..." OID. 825 * {0,6,...} return the aggregation label of the "..." OID. 826 */ 827 828 #ifdef SYSCTL_DEBUG 829 static void 830 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 831 { 832 int k; 833 struct sysctl_oid *oidp; 834 835 SYSCTL_ASSERT_LOCKED(); 836 SLIST_FOREACH(oidp, l, oid_link) { 837 838 for (k=0; k<i; k++) 839 printf(" "); 840 841 printf("%d %s ", oidp->oid_number, oidp->oid_name); 842 843 printf("%c%c", 844 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 845 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 846 847 if (oidp->oid_handler) 848 printf(" *Handler"); 849 850 switch (oidp->oid_kind & CTLTYPE) { 851 case CTLTYPE_NODE: 852 printf(" Node\n"); 853 if (!oidp->oid_handler) { 854 sysctl_sysctl_debug_dump_node( 855 SYSCTL_CHILDREN(oidp), i + 2); 856 } 857 break; 858 case CTLTYPE_INT: printf(" Int\n"); break; 859 case CTLTYPE_UINT: printf(" u_int\n"); break; 860 case CTLTYPE_LONG: printf(" Long\n"); break; 861 case CTLTYPE_ULONG: printf(" u_long\n"); break; 862 case CTLTYPE_STRING: printf(" String\n"); break; 863 case CTLTYPE_S8: printf(" int8_t\n"); break; 864 case CTLTYPE_S16: printf(" int16_t\n"); break; 865 case CTLTYPE_S32: printf(" int32_t\n"); break; 866 case CTLTYPE_S64: printf(" int64_t\n"); break; 867 case CTLTYPE_U8: printf(" uint8_t\n"); break; 868 case CTLTYPE_U16: printf(" uint16_t\n"); break; 869 case CTLTYPE_U32: printf(" uint32_t\n"); break; 870 case CTLTYPE_U64: printf(" uint64_t\n"); break; 871 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; 872 default: printf("\n"); 873 } 874 875 } 876 } 877 878 static int 879 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 880 { 881 struct rm_priotracker tracker; 882 int error; 883 884 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 885 if (error) 886 return (error); 887 SYSCTL_RLOCK(&tracker); 888 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 889 SYSCTL_RUNLOCK(&tracker); 890 return (ENOENT); 891 } 892 893 SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD|CTLFLAG_MPSAFE, 894 0, 0, sysctl_sysctl_debug, "-", ""); 895 #endif 896 897 static int 898 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 899 { 900 int *name = (int *) arg1; 901 u_int namelen = arg2; 902 int error = 0; 903 struct sysctl_oid *oid; 904 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 905 struct rm_priotracker tracker; 906 char buf[10]; 907 908 SYSCTL_RLOCK(&tracker); 909 while (namelen) { 910 if (!lsp) { 911 snprintf(buf,sizeof(buf),"%d",*name); 912 if (req->oldidx) 913 error = SYSCTL_OUT(req, ".", 1); 914 if (!error) 915 error = SYSCTL_OUT(req, buf, strlen(buf)); 916 if (error) 917 goto out; 918 namelen--; 919 name++; 920 continue; 921 } 922 lsp2 = NULL; 923 SLIST_FOREACH(oid, lsp, oid_link) { 924 if (oid->oid_number != *name) 925 continue; 926 927 if (req->oldidx) 928 error = SYSCTL_OUT(req, ".", 1); 929 if (!error) 930 error = SYSCTL_OUT(req, oid->oid_name, 931 strlen(oid->oid_name)); 932 if (error) 933 goto out; 934 935 namelen--; 936 name++; 937 938 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 939 break; 940 941 if (oid->oid_handler) 942 break; 943 944 lsp2 = SYSCTL_CHILDREN(oid); 945 break; 946 } 947 lsp = lsp2; 948 } 949 error = SYSCTL_OUT(req, "", 1); 950 out: 951 SYSCTL_RUNLOCK(&tracker); 952 return (error); 953 } 954 955 /* 956 * XXXRW/JA: Shouldn't return name data for nodes that we don't permit in 957 * capability mode. 958 */ 959 static SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, 960 sysctl_sysctl_name, ""); 961 962 static int 963 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 964 int *next, int *len, int level, struct sysctl_oid **oidpp) 965 { 966 struct sysctl_oid *oidp; 967 968 SYSCTL_ASSERT_LOCKED(); 969 *len = level; 970 SLIST_FOREACH(oidp, lsp, oid_link) { 971 *next = oidp->oid_number; 972 *oidpp = oidp; 973 974 if (oidp->oid_kind & CTLFLAG_SKIP) 975 continue; 976 977 if (!namelen) { 978 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 979 return (0); 980 if (oidp->oid_handler) 981 /* We really should call the handler here...*/ 982 return (0); 983 lsp = SYSCTL_CHILDREN(oidp); 984 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 985 len, level+1, oidpp)) 986 return (0); 987 goto emptynode; 988 } 989 990 if (oidp->oid_number < *name) 991 continue; 992 993 if (oidp->oid_number > *name) { 994 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 995 return (0); 996 if (oidp->oid_handler) 997 return (0); 998 lsp = SYSCTL_CHILDREN(oidp); 999 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 1000 next+1, len, level+1, oidpp)) 1001 return (0); 1002 goto next; 1003 } 1004 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1005 continue; 1006 1007 if (oidp->oid_handler) 1008 continue; 1009 1010 lsp = SYSCTL_CHILDREN(oidp); 1011 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 1012 len, level+1, oidpp)) 1013 return (0); 1014 next: 1015 namelen = 1; 1016 emptynode: 1017 *len = level; 1018 } 1019 return (1); 1020 } 1021 1022 static int 1023 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 1024 { 1025 int *name = (int *) arg1; 1026 u_int namelen = arg2; 1027 int i, j, error; 1028 struct sysctl_oid *oid; 1029 struct sysctl_oid_list *lsp = &sysctl__children; 1030 struct rm_priotracker tracker; 1031 int newoid[CTL_MAXNAME]; 1032 1033 SYSCTL_RLOCK(&tracker); 1034 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 1035 SYSCTL_RUNLOCK(&tracker); 1036 if (i) 1037 return (ENOENT); 1038 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 1039 return (error); 1040 } 1041 1042 /* 1043 * XXXRW/JA: Shouldn't return next data for nodes that we don't permit in 1044 * capability mode. 1045 */ 1046 static SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, 1047 sysctl_sysctl_next, ""); 1048 1049 static int 1050 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) 1051 { 1052 struct sysctl_oid *oidp; 1053 struct sysctl_oid_list *lsp = &sysctl__children; 1054 char *p; 1055 1056 SYSCTL_ASSERT_LOCKED(); 1057 1058 for (*len = 0; *len < CTL_MAXNAME;) { 1059 p = strsep(&name, "."); 1060 1061 oidp = SLIST_FIRST(lsp); 1062 for (;; oidp = SLIST_NEXT(oidp, oid_link)) { 1063 if (oidp == NULL) 1064 return (ENOENT); 1065 if (strcmp(p, oidp->oid_name) == 0) 1066 break; 1067 } 1068 *oid++ = oidp->oid_number; 1069 (*len)++; 1070 1071 if (name == NULL || *name == '\0') { 1072 if (oidpp) 1073 *oidpp = oidp; 1074 return (0); 1075 } 1076 1077 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 1078 break; 1079 1080 if (oidp->oid_handler) 1081 break; 1082 1083 lsp = SYSCTL_CHILDREN(oidp); 1084 } 1085 return (ENOENT); 1086 } 1087 1088 static int 1089 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 1090 { 1091 char *p; 1092 int error, oid[CTL_MAXNAME], len = 0; 1093 struct sysctl_oid *op = NULL; 1094 struct rm_priotracker tracker; 1095 1096 if (!req->newlen) 1097 return (ENOENT); 1098 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 1099 return (ENAMETOOLONG); 1100 1101 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); 1102 1103 error = SYSCTL_IN(req, p, req->newlen); 1104 if (error) { 1105 free(p, M_SYSCTL); 1106 return (error); 1107 } 1108 1109 p [req->newlen] = '\0'; 1110 1111 SYSCTL_RLOCK(&tracker); 1112 error = name2oid(p, oid, &len, &op); 1113 SYSCTL_RUNLOCK(&tracker); 1114 1115 free(p, M_SYSCTL); 1116 1117 if (error) 1118 return (error); 1119 1120 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 1121 return (error); 1122 } 1123 1124 /* 1125 * XXXRW/JA: Shouldn't return name2oid data for nodes that we don't permit in 1126 * capability mode. 1127 */ 1128 SYSCTL_PROC(_sysctl, 3, name2oid, 1129 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_ANYBODY | CTLFLAG_MPSAFE 1130 | CTLFLAG_CAPRW, 0, 0, sysctl_sysctl_name2oid, "I", ""); 1131 1132 static int 1133 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 1134 { 1135 struct sysctl_oid *oid; 1136 struct rm_priotracker tracker; 1137 int error; 1138 1139 SYSCTL_RLOCK(&tracker); 1140 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1141 if (error) 1142 goto out; 1143 1144 if (oid->oid_fmt == NULL) { 1145 error = ENOENT; 1146 goto out; 1147 } 1148 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 1149 if (error) 1150 goto out; 1151 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 1152 out: 1153 SYSCTL_RUNLOCK(&tracker); 1154 return (error); 1155 } 1156 1157 1158 static SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLFLAG_CAPRD, 1159 sysctl_sysctl_oidfmt, ""); 1160 1161 static int 1162 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 1163 { 1164 struct sysctl_oid *oid; 1165 struct rm_priotracker tracker; 1166 int error; 1167 1168 SYSCTL_RLOCK(&tracker); 1169 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1170 if (error) 1171 goto out; 1172 1173 if (oid->oid_descr == NULL) { 1174 error = ENOENT; 1175 goto out; 1176 } 1177 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 1178 out: 1179 SYSCTL_RUNLOCK(&tracker); 1180 return (error); 1181 } 1182 1183 static SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD|CTLFLAG_MPSAFE|CTLFLAG_CAPRD, 1184 sysctl_sysctl_oiddescr, ""); 1185 1186 static int 1187 sysctl_sysctl_oidlabel(SYSCTL_HANDLER_ARGS) 1188 { 1189 struct sysctl_oid *oid; 1190 struct rm_priotracker tracker; 1191 int error; 1192 1193 SYSCTL_RLOCK(&tracker); 1194 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 1195 if (error) 1196 goto out; 1197 1198 if (oid->oid_label == NULL) { 1199 error = ENOENT; 1200 goto out; 1201 } 1202 error = SYSCTL_OUT(req, oid->oid_label, strlen(oid->oid_label) + 1); 1203 out: 1204 SYSCTL_RUNLOCK(&tracker); 1205 return (error); 1206 } 1207 1208 static SYSCTL_NODE(_sysctl, 6, oidlabel, 1209 CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, sysctl_sysctl_oidlabel, ""); 1210 1211 /* 1212 * Default "handler" functions. 1213 */ 1214 1215 /* 1216 * Handle a bool. 1217 * Two cases: 1218 * a variable: point arg1 at it. 1219 * a constant: pass it in arg2. 1220 */ 1221 1222 int 1223 sysctl_handle_bool(SYSCTL_HANDLER_ARGS) 1224 { 1225 uint8_t temp; 1226 int error; 1227 1228 /* 1229 * Attempt to get a coherent snapshot by making a copy of the data. 1230 */ 1231 if (arg1) 1232 temp = *(bool *)arg1 ? 1 : 0; 1233 else 1234 temp = arg2 ? 1 : 0; 1235 1236 error = SYSCTL_OUT(req, &temp, sizeof(temp)); 1237 if (error || !req->newptr) 1238 return (error); 1239 1240 if (!arg1) 1241 error = EPERM; 1242 else { 1243 error = SYSCTL_IN(req, &temp, sizeof(temp)); 1244 if (!error) 1245 *(bool *)arg1 = temp ? 1 : 0; 1246 } 1247 return (error); 1248 } 1249 1250 /* 1251 * Handle an int8_t, signed or unsigned. 1252 * Two cases: 1253 * a variable: point arg1 at it. 1254 * a constant: pass it in arg2. 1255 */ 1256 1257 int 1258 sysctl_handle_8(SYSCTL_HANDLER_ARGS) 1259 { 1260 int8_t tmpout; 1261 int error = 0; 1262 1263 /* 1264 * Attempt to get a coherent snapshot by making a copy of the data. 1265 */ 1266 if (arg1) 1267 tmpout = *(int8_t *)arg1; 1268 else 1269 tmpout = arg2; 1270 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1271 1272 if (error || !req->newptr) 1273 return (error); 1274 1275 if (!arg1) 1276 error = EPERM; 1277 else 1278 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1279 return (error); 1280 } 1281 1282 /* 1283 * Handle an int16_t, signed or unsigned. 1284 * Two cases: 1285 * a variable: point arg1 at it. 1286 * a constant: pass it in arg2. 1287 */ 1288 1289 int 1290 sysctl_handle_16(SYSCTL_HANDLER_ARGS) 1291 { 1292 int16_t tmpout; 1293 int error = 0; 1294 1295 /* 1296 * Attempt to get a coherent snapshot by making a copy of the data. 1297 */ 1298 if (arg1) 1299 tmpout = *(int16_t *)arg1; 1300 else 1301 tmpout = arg2; 1302 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1303 1304 if (error || !req->newptr) 1305 return (error); 1306 1307 if (!arg1) 1308 error = EPERM; 1309 else 1310 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1311 return (error); 1312 } 1313 1314 /* 1315 * Handle an int32_t, signed or unsigned. 1316 * Two cases: 1317 * a variable: point arg1 at it. 1318 * a constant: pass it in arg2. 1319 */ 1320 1321 int 1322 sysctl_handle_32(SYSCTL_HANDLER_ARGS) 1323 { 1324 int32_t tmpout; 1325 int error = 0; 1326 1327 /* 1328 * Attempt to get a coherent snapshot by making a copy of the data. 1329 */ 1330 if (arg1) 1331 tmpout = *(int32_t *)arg1; 1332 else 1333 tmpout = arg2; 1334 error = SYSCTL_OUT(req, &tmpout, sizeof(tmpout)); 1335 1336 if (error || !req->newptr) 1337 return (error); 1338 1339 if (!arg1) 1340 error = EPERM; 1341 else 1342 error = SYSCTL_IN(req, arg1, sizeof(tmpout)); 1343 return (error); 1344 } 1345 1346 /* 1347 * Handle an int, signed or unsigned. 1348 * Two cases: 1349 * a variable: point arg1 at it. 1350 * a constant: pass it in arg2. 1351 */ 1352 1353 int 1354 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 1355 { 1356 int tmpout, error = 0; 1357 1358 /* 1359 * Attempt to get a coherent snapshot by making a copy of the data. 1360 */ 1361 if (arg1) 1362 tmpout = *(int *)arg1; 1363 else 1364 tmpout = arg2; 1365 error = SYSCTL_OUT(req, &tmpout, sizeof(int)); 1366 1367 if (error || !req->newptr) 1368 return (error); 1369 1370 if (!arg1) 1371 error = EPERM; 1372 else 1373 error = SYSCTL_IN(req, arg1, sizeof(int)); 1374 return (error); 1375 } 1376 1377 /* 1378 * Based on on sysctl_handle_int() convert milliseconds into ticks. 1379 * Note: this is used by TCP. 1380 */ 1381 1382 int 1383 sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) 1384 { 1385 int error, s, tt; 1386 1387 tt = *(int *)arg1; 1388 s = (int)((int64_t)tt * 1000 / hz); 1389 1390 error = sysctl_handle_int(oidp, &s, 0, req); 1391 if (error || !req->newptr) 1392 return (error); 1393 1394 tt = (int)((int64_t)s * hz / 1000); 1395 if (tt < 1) 1396 return (EINVAL); 1397 1398 *(int *)arg1 = tt; 1399 return (0); 1400 } 1401 1402 1403 /* 1404 * Handle a long, signed or unsigned. 1405 * Two cases: 1406 * a variable: point arg1 at it. 1407 * a constant: pass it in arg2. 1408 */ 1409 1410 int 1411 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 1412 { 1413 int error = 0; 1414 long tmplong; 1415 #ifdef SCTL_MASK32 1416 int tmpint; 1417 #endif 1418 1419 /* 1420 * Attempt to get a coherent snapshot by making a copy of the data. 1421 */ 1422 if (arg1) 1423 tmplong = *(long *)arg1; 1424 else 1425 tmplong = arg2; 1426 #ifdef SCTL_MASK32 1427 if (req->flags & SCTL_MASK32) { 1428 tmpint = tmplong; 1429 error = SYSCTL_OUT(req, &tmpint, sizeof(int)); 1430 } else 1431 #endif 1432 error = SYSCTL_OUT(req, &tmplong, sizeof(long)); 1433 1434 if (error || !req->newptr) 1435 return (error); 1436 1437 if (!arg1) 1438 error = EPERM; 1439 #ifdef SCTL_MASK32 1440 else if (req->flags & SCTL_MASK32) { 1441 error = SYSCTL_IN(req, &tmpint, sizeof(int)); 1442 *(long *)arg1 = (long)tmpint; 1443 } 1444 #endif 1445 else 1446 error = SYSCTL_IN(req, arg1, sizeof(long)); 1447 return (error); 1448 } 1449 1450 /* 1451 * Handle a 64 bit int, signed or unsigned. 1452 * Two cases: 1453 * a variable: point arg1 at it. 1454 * a constant: pass it in arg2. 1455 */ 1456 int 1457 sysctl_handle_64(SYSCTL_HANDLER_ARGS) 1458 { 1459 int error = 0; 1460 uint64_t tmpout; 1461 1462 /* 1463 * Attempt to get a coherent snapshot by making a copy of the data. 1464 */ 1465 if (arg1) 1466 tmpout = *(uint64_t *)arg1; 1467 else 1468 tmpout = arg2; 1469 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t)); 1470 1471 if (error || !req->newptr) 1472 return (error); 1473 1474 if (!arg1) 1475 error = EPERM; 1476 else 1477 error = SYSCTL_IN(req, arg1, sizeof(uint64_t)); 1478 return (error); 1479 } 1480 1481 /* 1482 * Handle our generic '\0' terminated 'C' string. 1483 * Two cases: 1484 * a variable string: point arg1 at it, arg2 is max length. 1485 * a constant string: point arg1 at it, arg2 is zero. 1486 */ 1487 1488 int 1489 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 1490 { 1491 size_t outlen; 1492 int error = 0, ro_string = 0; 1493 1494 /* 1495 * A zero-length buffer indicates a fixed size read-only 1496 * string: 1497 */ 1498 if (arg2 == 0) { 1499 arg2 = strlen((char *)arg1) + 1; 1500 ro_string = 1; 1501 } 1502 1503 if (req->oldptr != NULL) { 1504 char *tmparg; 1505 1506 if (ro_string) { 1507 tmparg = arg1; 1508 } else { 1509 /* try to make a coherent snapshot of the string */ 1510 tmparg = malloc(arg2, M_SYSCTLTMP, M_WAITOK); 1511 memcpy(tmparg, arg1, arg2); 1512 } 1513 1514 outlen = strnlen(tmparg, arg2 - 1) + 1; 1515 error = SYSCTL_OUT(req, tmparg, outlen); 1516 1517 if (!ro_string) 1518 free(tmparg, M_SYSCTLTMP); 1519 } else { 1520 outlen = strnlen((char *)arg1, arg2 - 1) + 1; 1521 error = SYSCTL_OUT(req, NULL, outlen); 1522 } 1523 if (error || !req->newptr) 1524 return (error); 1525 1526 if ((req->newlen - req->newidx) >= arg2) { 1527 error = EINVAL; 1528 } else { 1529 arg2 = (req->newlen - req->newidx); 1530 error = SYSCTL_IN(req, arg1, arg2); 1531 ((char *)arg1)[arg2] = '\0'; 1532 } 1533 return (error); 1534 } 1535 1536 /* 1537 * Handle any kind of opaque data. 1538 * arg1 points to it, arg2 is the size. 1539 */ 1540 1541 int 1542 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 1543 { 1544 int error, tries; 1545 u_int generation; 1546 struct sysctl_req req2; 1547 1548 /* 1549 * Attempt to get a coherent snapshot, by using the thread 1550 * pre-emption counter updated from within mi_switch() to 1551 * determine if we were pre-empted during a bcopy() or 1552 * copyout(). Make 3 attempts at doing this before giving up. 1553 * If we encounter an error, stop immediately. 1554 */ 1555 tries = 0; 1556 req2 = *req; 1557 retry: 1558 generation = curthread->td_generation; 1559 error = SYSCTL_OUT(req, arg1, arg2); 1560 if (error) 1561 return (error); 1562 tries++; 1563 if (generation != curthread->td_generation && tries < 3) { 1564 *req = req2; 1565 goto retry; 1566 } 1567 1568 error = SYSCTL_IN(req, arg1, arg2); 1569 1570 return (error); 1571 } 1572 1573 /* 1574 * Transfer functions to/from kernel space. 1575 * XXX: rather untested at this point 1576 */ 1577 static int 1578 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 1579 { 1580 size_t i = 0; 1581 1582 if (req->oldptr) { 1583 i = l; 1584 if (req->oldlen <= req->oldidx) 1585 i = 0; 1586 else 1587 if (i > req->oldlen - req->oldidx) 1588 i = req->oldlen - req->oldidx; 1589 if (i > 0) 1590 bcopy(p, (char *)req->oldptr + req->oldidx, i); 1591 } 1592 req->oldidx += l; 1593 if (req->oldptr && i != l) 1594 return (ENOMEM); 1595 return (0); 1596 } 1597 1598 static int 1599 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 1600 { 1601 if (!req->newptr) 1602 return (0); 1603 if (req->newlen - req->newidx < l) 1604 return (EINVAL); 1605 bcopy((char *)req->newptr + req->newidx, p, l); 1606 req->newidx += l; 1607 return (0); 1608 } 1609 1610 int 1611 kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1612 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) 1613 { 1614 int error = 0; 1615 struct sysctl_req req; 1616 1617 bzero(&req, sizeof req); 1618 1619 req.td = td; 1620 req.flags = flags; 1621 1622 if (oldlenp) { 1623 req.oldlen = *oldlenp; 1624 } 1625 req.validlen = req.oldlen; 1626 1627 if (old) { 1628 req.oldptr= old; 1629 } 1630 1631 if (new != NULL) { 1632 req.newlen = newlen; 1633 req.newptr = new; 1634 } 1635 1636 req.oldfunc = sysctl_old_kernel; 1637 req.newfunc = sysctl_new_kernel; 1638 req.lock = REQ_UNWIRED; 1639 1640 error = sysctl_root(0, name, namelen, &req); 1641 1642 if (req.lock == REQ_WIRED && req.validlen > 0) 1643 vsunlock(req.oldptr, req.validlen); 1644 1645 if (error && error != ENOMEM) 1646 return (error); 1647 1648 if (retval) { 1649 if (req.oldptr && req.oldidx > req.validlen) 1650 *retval = req.validlen; 1651 else 1652 *retval = req.oldidx; 1653 } 1654 return (error); 1655 } 1656 1657 int 1658 kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp, 1659 void *new, size_t newlen, size_t *retval, int flags) 1660 { 1661 int oid[CTL_MAXNAME]; 1662 size_t oidlen, plen; 1663 int error; 1664 1665 oid[0] = 0; /* sysctl internal magic */ 1666 oid[1] = 3; /* name2oid */ 1667 oidlen = sizeof(oid); 1668 1669 error = kernel_sysctl(td, oid, 2, oid, &oidlen, 1670 (void *)name, strlen(name), &plen, flags); 1671 if (error) 1672 return (error); 1673 1674 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp, 1675 new, newlen, retval, flags); 1676 return (error); 1677 } 1678 1679 /* 1680 * Transfer function to/from user space. 1681 */ 1682 static int 1683 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1684 { 1685 size_t i, len, origidx; 1686 int error; 1687 1688 origidx = req->oldidx; 1689 req->oldidx += l; 1690 if (req->oldptr == NULL) 1691 return (0); 1692 /* 1693 * If we have not wired the user supplied buffer and we are currently 1694 * holding locks, drop a witness warning, as it's possible that 1695 * write operations to the user page can sleep. 1696 */ 1697 if (req->lock != REQ_WIRED) 1698 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1699 "sysctl_old_user()"); 1700 i = l; 1701 len = req->validlen; 1702 if (len <= origidx) 1703 i = 0; 1704 else { 1705 if (i > len - origidx) 1706 i = len - origidx; 1707 if (req->lock == REQ_WIRED) { 1708 error = copyout_nofault(p, (char *)req->oldptr + 1709 origidx, i); 1710 } else 1711 error = copyout(p, (char *)req->oldptr + origidx, i); 1712 if (error != 0) 1713 return (error); 1714 } 1715 if (i < l) 1716 return (ENOMEM); 1717 return (0); 1718 } 1719 1720 static int 1721 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1722 { 1723 int error; 1724 1725 if (!req->newptr) 1726 return (0); 1727 if (req->newlen - req->newidx < l) 1728 return (EINVAL); 1729 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1730 "sysctl_new_user()"); 1731 error = copyin((char *)req->newptr + req->newidx, p, l); 1732 req->newidx += l; 1733 return (error); 1734 } 1735 1736 /* 1737 * Wire the user space destination buffer. If set to a value greater than 1738 * zero, the len parameter limits the maximum amount of wired memory. 1739 */ 1740 int 1741 sysctl_wire_old_buffer(struct sysctl_req *req, size_t len) 1742 { 1743 int ret; 1744 size_t wiredlen; 1745 1746 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen; 1747 ret = 0; 1748 if (req->lock != REQ_WIRED && req->oldptr && 1749 req->oldfunc == sysctl_old_user) { 1750 if (wiredlen != 0) { 1751 ret = vslock(req->oldptr, wiredlen); 1752 if (ret != 0) { 1753 if (ret != ENOMEM) 1754 return (ret); 1755 wiredlen = 0; 1756 } 1757 } 1758 req->lock = REQ_WIRED; 1759 req->validlen = wiredlen; 1760 } 1761 return (0); 1762 } 1763 1764 int 1765 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 1766 int *nindx, struct sysctl_req *req) 1767 { 1768 struct sysctl_oid_list *lsp; 1769 struct sysctl_oid *oid; 1770 int indx; 1771 1772 SYSCTL_ASSERT_LOCKED(); 1773 lsp = &sysctl__children; 1774 indx = 0; 1775 while (indx < CTL_MAXNAME) { 1776 SLIST_FOREACH(oid, lsp, oid_link) { 1777 if (oid->oid_number == name[indx]) 1778 break; 1779 } 1780 if (oid == NULL) 1781 return (ENOENT); 1782 1783 indx++; 1784 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1785 if (oid->oid_handler != NULL || indx == namelen) { 1786 *noid = oid; 1787 if (nindx != NULL) 1788 *nindx = indx; 1789 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 1790 ("%s found DYING node %p", __func__, oid)); 1791 return (0); 1792 } 1793 lsp = SYSCTL_CHILDREN(oid); 1794 } else if (indx == namelen) { 1795 *noid = oid; 1796 if (nindx != NULL) 1797 *nindx = indx; 1798 KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, 1799 ("%s found DYING node %p", __func__, oid)); 1800 return (0); 1801 } else { 1802 return (ENOTDIR); 1803 } 1804 } 1805 return (ENOENT); 1806 } 1807 1808 /* 1809 * Traverse our tree, and find the right node, execute whatever it points 1810 * to, and return the resulting error code. 1811 */ 1812 1813 static int 1814 sysctl_root(SYSCTL_HANDLER_ARGS) 1815 { 1816 struct sysctl_oid *oid; 1817 struct rm_priotracker tracker; 1818 int error, indx, lvl; 1819 1820 SYSCTL_RLOCK(&tracker); 1821 1822 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 1823 if (error) 1824 goto out; 1825 1826 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1827 /* 1828 * You can't call a sysctl when it's a node, but has 1829 * no handler. Inform the user that it's a node. 1830 * The indx may or may not be the same as namelen. 1831 */ 1832 if (oid->oid_handler == NULL) { 1833 error = EISDIR; 1834 goto out; 1835 } 1836 } 1837 1838 /* Is this sysctl writable? */ 1839 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) { 1840 error = EPERM; 1841 goto out; 1842 } 1843 1844 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL")); 1845 1846 #ifdef CAPABILITY_MODE 1847 /* 1848 * If the process is in capability mode, then don't permit reading or 1849 * writing unless specifically granted for the node. 1850 */ 1851 if (IN_CAPABILITY_MODE(req->td)) { 1852 if ((req->oldptr && !(oid->oid_kind & CTLFLAG_CAPRD)) || 1853 (req->newptr && !(oid->oid_kind & CTLFLAG_CAPWR))) { 1854 error = EPERM; 1855 goto out; 1856 } 1857 } 1858 #endif 1859 1860 /* Is this sysctl sensitive to securelevels? */ 1861 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) { 1862 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE; 1863 error = securelevel_gt(req->td->td_ucred, lvl); 1864 if (error) 1865 goto out; 1866 } 1867 1868 /* Is this sysctl writable by only privileged users? */ 1869 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) { 1870 int priv; 1871 1872 if (oid->oid_kind & CTLFLAG_PRISON) 1873 priv = PRIV_SYSCTL_WRITEJAIL; 1874 #ifdef VIMAGE 1875 else if ((oid->oid_kind & CTLFLAG_VNET) && 1876 prison_owns_vnet(req->td->td_ucred)) 1877 priv = PRIV_SYSCTL_WRITEJAIL; 1878 #endif 1879 else 1880 priv = PRIV_SYSCTL_WRITE; 1881 error = priv_check(req->td, priv); 1882 if (error) 1883 goto out; 1884 } 1885 1886 if (!oid->oid_handler) { 1887 error = EINVAL; 1888 goto out; 1889 } 1890 1891 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1892 arg1 = (int *)arg1 + indx; 1893 arg2 -= indx; 1894 } else { 1895 arg1 = oid->oid_arg1; 1896 arg2 = oid->oid_arg2; 1897 } 1898 #ifdef MAC 1899 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2, 1900 req); 1901 if (error != 0) 1902 goto out; 1903 #endif 1904 #ifdef VIMAGE 1905 if ((oid->oid_kind & CTLFLAG_VNET) && arg1 != NULL) 1906 arg1 = (void *)(curvnet->vnet_data_base + (uintptr_t)arg1); 1907 #endif 1908 error = sysctl_root_handler_locked(oid, arg1, arg2, req, &tracker); 1909 1910 out: 1911 SYSCTL_RUNLOCK(&tracker); 1912 return (error); 1913 } 1914 1915 #ifndef _SYS_SYSPROTO_H_ 1916 struct sysctl_args { 1917 int *name; 1918 u_int namelen; 1919 void *old; 1920 size_t *oldlenp; 1921 void *new; 1922 size_t newlen; 1923 }; 1924 #endif 1925 int 1926 sys___sysctl(struct thread *td, struct sysctl_args *uap) 1927 { 1928 int error, i, name[CTL_MAXNAME]; 1929 size_t j; 1930 1931 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 1932 return (EINVAL); 1933 1934 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 1935 if (error) 1936 return (error); 1937 1938 error = userland_sysctl(td, name, uap->namelen, 1939 uap->old, uap->oldlenp, 0, 1940 uap->new, uap->newlen, &j, 0); 1941 if (error && error != ENOMEM) 1942 return (error); 1943 if (uap->oldlenp) { 1944 i = copyout(&j, uap->oldlenp, sizeof(j)); 1945 if (i) 1946 return (i); 1947 } 1948 return (error); 1949 } 1950 1951 /* 1952 * This is used from various compatibility syscalls too. That's why name 1953 * must be in kernel space. 1954 */ 1955 int 1956 userland_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1957 size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval, 1958 int flags) 1959 { 1960 int error = 0, memlocked; 1961 struct sysctl_req req; 1962 1963 bzero(&req, sizeof req); 1964 1965 req.td = td; 1966 req.flags = flags; 1967 1968 if (oldlenp) { 1969 if (inkernel) { 1970 req.oldlen = *oldlenp; 1971 } else { 1972 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 1973 if (error) 1974 return (error); 1975 } 1976 } 1977 req.validlen = req.oldlen; 1978 1979 if (old) { 1980 if (!useracc(old, req.oldlen, VM_PROT_WRITE)) 1981 return (EFAULT); 1982 req.oldptr= old; 1983 } 1984 1985 if (new != NULL) { 1986 if (!useracc(new, newlen, VM_PROT_READ)) 1987 return (EFAULT); 1988 req.newlen = newlen; 1989 req.newptr = new; 1990 } 1991 1992 req.oldfunc = sysctl_old_user; 1993 req.newfunc = sysctl_new_user; 1994 req.lock = REQ_UNWIRED; 1995 1996 #ifdef KTRACE 1997 if (KTRPOINT(curthread, KTR_SYSCTL)) 1998 ktrsysctl(name, namelen); 1999 #endif 2000 2001 if (req.oldptr && req.oldlen > PAGE_SIZE) { 2002 memlocked = 1; 2003 sx_xlock(&sysctlmemlock); 2004 } else 2005 memlocked = 0; 2006 CURVNET_SET(TD_TO_VNET(td)); 2007 2008 for (;;) { 2009 req.oldidx = 0; 2010 req.newidx = 0; 2011 error = sysctl_root(0, name, namelen, &req); 2012 if (error != EAGAIN) 2013 break; 2014 kern_yield(PRI_USER); 2015 } 2016 2017 CURVNET_RESTORE(); 2018 2019 if (req.lock == REQ_WIRED && req.validlen > 0) 2020 vsunlock(req.oldptr, req.validlen); 2021 if (memlocked) 2022 sx_xunlock(&sysctlmemlock); 2023 2024 if (error && error != ENOMEM) 2025 return (error); 2026 2027 if (retval) { 2028 if (req.oldptr && req.oldidx > req.validlen) 2029 *retval = req.validlen; 2030 else 2031 *retval = req.oldidx; 2032 } 2033 return (error); 2034 } 2035 2036 /* 2037 * Drain into a sysctl struct. The user buffer should be wired if a page 2038 * fault would cause issue. 2039 */ 2040 static int 2041 sbuf_sysctl_drain(void *arg, const char *data, int len) 2042 { 2043 struct sysctl_req *req = arg; 2044 int error; 2045 2046 error = SYSCTL_OUT(req, data, len); 2047 KASSERT(error >= 0, ("Got unexpected negative value %d", error)); 2048 return (error == 0 ? len : -error); 2049 } 2050 2051 struct sbuf * 2052 sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, 2053 struct sysctl_req *req) 2054 { 2055 2056 /* Supply a default buffer size if none given. */ 2057 if (buf == NULL && length == 0) 2058 length = 64; 2059 s = sbuf_new(s, buf, length, SBUF_FIXEDLEN | SBUF_INCLUDENUL); 2060 sbuf_set_drain(s, sbuf_sysctl_drain, req); 2061 return (s); 2062 } 2063