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 * 4. 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_compat.h" 42 #include "opt_ktrace.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/sysctl.h> 48 #include <sys/malloc.h> 49 #include <sys/priv.h> 50 #include <sys/proc.h> 51 #include <sys/jail.h> 52 #include <sys/lock.h> 53 #include <sys/mutex.h> 54 #include <sys/sx.h> 55 #include <sys/sysproto.h> 56 #include <sys/uio.h> 57 #include <sys/vimage.h> 58 #ifdef KTRACE 59 #include <sys/ktrace.h> 60 #endif 61 62 #include <security/mac/mac_framework.h> 63 64 #include <vm/vm.h> 65 #include <vm/vm_extern.h> 66 67 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic"); 68 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids"); 69 static MALLOC_DEFINE(M_SYSCTLTMP, "sysctltmp", "sysctl temp output buffer"); 70 71 /* 72 * The sysctllock protects the MIB tree. It also protects sysctl 73 * contexts used with dynamic sysctls. The sysctl_register_oid() and 74 * sysctl_unregister_oid() routines require the sysctllock to already 75 * be held, so the sysctl_lock() and sysctl_unlock() routines are 76 * provided for the few places in the kernel which need to use that 77 * API rather than using the dynamic API. Use of the dynamic API is 78 * strongly encouraged for most code. 79 * 80 * The sysctlmemlock is used to limit the amount of user memory wired for 81 * sysctl requests. This is implemented by serializing any userland 82 * sysctl requests larger than a single page via an exclusive lock. 83 */ 84 static struct sx sysctllock; 85 static struct sx sysctlmemlock; 86 87 #define SYSCTL_SLOCK() sx_slock(&sysctllock) 88 #define SYSCTL_SUNLOCK() sx_sunlock(&sysctllock) 89 #define SYSCTL_XLOCK() sx_xlock(&sysctllock) 90 #define SYSCTL_XUNLOCK() sx_xunlock(&sysctllock) 91 #define SYSCTL_ASSERT_XLOCKED() sx_assert(&sysctllock, SA_XLOCKED) 92 #define SYSCTL_ASSERT_LOCKED() sx_assert(&sysctllock, SA_LOCKED) 93 #define SYSCTL_INIT() sx_init(&sysctllock, "sysctl lock") 94 95 static int sysctl_root(SYSCTL_HANDLER_ARGS); 96 97 struct sysctl_oid_list sysctl__children; /* root list */ 98 99 static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, 100 int recurse); 101 102 static struct sysctl_oid * 103 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list) 104 { 105 struct sysctl_oid *oidp; 106 107 SYSCTL_ASSERT_LOCKED(); 108 SLIST_FOREACH(oidp, list, oid_link) { 109 if (strcmp(oidp->oid_name, name) == 0) { 110 return (oidp); 111 } 112 } 113 return (NULL); 114 } 115 116 /* 117 * Initialization of the MIB tree. 118 * 119 * Order by number in each list. 120 */ 121 void 122 sysctl_lock(void) 123 { 124 125 SYSCTL_XLOCK(); 126 } 127 128 void 129 sysctl_unlock(void) 130 { 131 132 SYSCTL_XUNLOCK(); 133 } 134 135 void 136 sysctl_register_oid(struct sysctl_oid *oidp) 137 { 138 struct sysctl_oid_list *parent = oidp->oid_parent; 139 struct sysctl_oid *p; 140 struct sysctl_oid *q; 141 142 /* 143 * First check if another oid with the same name already 144 * exists in the parent's list. 145 */ 146 SYSCTL_ASSERT_XLOCKED(); 147 p = sysctl_find_oidname(oidp->oid_name, parent); 148 if (p != NULL) { 149 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 150 p->oid_refcnt++; 151 return; 152 } else { 153 printf("can't re-use a leaf (%s)!\n", p->oid_name); 154 return; 155 } 156 } 157 /* 158 * If this oid has a number OID_AUTO, give it a number which 159 * is greater than any current oid. 160 * NOTE: DO NOT change the starting value here, change it in 161 * <sys/sysctl.h>, and make sure it is at least 256 to 162 * accomodate e.g. net.inet.raw as a static sysctl node. 163 */ 164 if (oidp->oid_number == OID_AUTO) { 165 static int newoid = CTL_AUTO_START; 166 167 oidp->oid_number = newoid++; 168 if (newoid == 0x7fffffff) 169 panic("out of oids"); 170 } 171 #if 0 172 else if (oidp->oid_number >= CTL_AUTO_START) { 173 /* do not panic; this happens when unregistering sysctl sets */ 174 printf("static sysctl oid too high: %d", oidp->oid_number); 175 } 176 #endif 177 178 /* 179 * Insert the oid into the parent's list in order. 180 */ 181 q = NULL; 182 SLIST_FOREACH(p, parent, oid_link) { 183 if (oidp->oid_number < p->oid_number) 184 break; 185 q = p; 186 } 187 if (q) 188 SLIST_INSERT_AFTER(q, oidp, oid_link); 189 else 190 SLIST_INSERT_HEAD(parent, oidp, oid_link); 191 } 192 193 void 194 sysctl_unregister_oid(struct sysctl_oid *oidp) 195 { 196 struct sysctl_oid *p; 197 int error; 198 199 SYSCTL_ASSERT_XLOCKED(); 200 error = ENOENT; 201 if (oidp->oid_number == OID_AUTO) { 202 error = EINVAL; 203 } else { 204 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 205 if (p == oidp) { 206 SLIST_REMOVE(oidp->oid_parent, oidp, 207 sysctl_oid, oid_link); 208 error = 0; 209 break; 210 } 211 } 212 } 213 214 /* 215 * This can happen when a module fails to register and is 216 * being unloaded afterwards. It should not be a panic() 217 * for normal use. 218 */ 219 if (error) 220 printf("%s: failed to unregister sysctl\n", __func__); 221 } 222 223 /* Initialize a new context to keep track of dynamically added sysctls. */ 224 int 225 sysctl_ctx_init(struct sysctl_ctx_list *c) 226 { 227 228 if (c == NULL) { 229 return (EINVAL); 230 } 231 232 /* 233 * No locking here, the caller is responsible for not adding 234 * new nodes to a context until after this function has 235 * returned. 236 */ 237 TAILQ_INIT(c); 238 return (0); 239 } 240 241 /* Free the context, and destroy all dynamic oids registered in this context */ 242 int 243 sysctl_ctx_free(struct sysctl_ctx_list *clist) 244 { 245 struct sysctl_ctx_entry *e, *e1; 246 int error; 247 248 error = 0; 249 /* 250 * First perform a "dry run" to check if it's ok to remove oids. 251 * XXX FIXME 252 * XXX This algorithm is a hack. But I don't know any 253 * XXX better solution for now... 254 */ 255 SYSCTL_XLOCK(); 256 TAILQ_FOREACH(e, clist, link) { 257 error = sysctl_remove_oid_locked(e->entry, 0, 0); 258 if (error) 259 break; 260 } 261 /* 262 * Restore deregistered entries, either from the end, 263 * or from the place where error occured. 264 * e contains the entry that was not unregistered 265 */ 266 if (error) 267 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 268 else 269 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 270 while (e1 != NULL) { 271 sysctl_register_oid(e1->entry); 272 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 273 } 274 if (error) { 275 SYSCTL_XUNLOCK(); 276 return(EBUSY); 277 } 278 /* Now really delete the entries */ 279 e = TAILQ_FIRST(clist); 280 while (e != NULL) { 281 e1 = TAILQ_NEXT(e, link); 282 error = sysctl_remove_oid_locked(e->entry, 1, 0); 283 if (error) 284 panic("sysctl_remove_oid: corrupt tree, entry: %s", 285 e->entry->oid_name); 286 free(e, M_SYSCTLOID); 287 e = e1; 288 } 289 SYSCTL_XUNLOCK(); 290 return (error); 291 } 292 293 /* Add an entry to the context */ 294 struct sysctl_ctx_entry * 295 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 296 { 297 struct sysctl_ctx_entry *e; 298 299 SYSCTL_ASSERT_XLOCKED(); 300 if (clist == NULL || oidp == NULL) 301 return(NULL); 302 e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 303 e->entry = oidp; 304 TAILQ_INSERT_HEAD(clist, e, link); 305 return (e); 306 } 307 308 /* Find an entry in the context */ 309 struct sysctl_ctx_entry * 310 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 311 { 312 struct sysctl_ctx_entry *e; 313 314 SYSCTL_ASSERT_LOCKED(); 315 if (clist == NULL || oidp == NULL) 316 return(NULL); 317 TAILQ_FOREACH(e, clist, link) { 318 if(e->entry == oidp) 319 return(e); 320 } 321 return (e); 322 } 323 324 /* 325 * Delete an entry from the context. 326 * NOTE: this function doesn't free oidp! You have to remove it 327 * with sysctl_remove_oid(). 328 */ 329 int 330 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 331 { 332 struct sysctl_ctx_entry *e; 333 334 if (clist == NULL || oidp == NULL) 335 return (EINVAL); 336 SYSCTL_XLOCK(); 337 e = sysctl_ctx_entry_find(clist, oidp); 338 if (e != NULL) { 339 TAILQ_REMOVE(clist, e, link); 340 SYSCTL_XUNLOCK(); 341 free(e, M_SYSCTLOID); 342 return (0); 343 } else { 344 SYSCTL_XUNLOCK(); 345 return (ENOENT); 346 } 347 } 348 349 /* 350 * Remove dynamically created sysctl trees. 351 * oidp - top of the tree to be removed 352 * del - if 0 - just deregister, otherwise free up entries as well 353 * recurse - if != 0 traverse the subtree to be deleted 354 */ 355 int 356 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 357 { 358 int error; 359 360 SYSCTL_XLOCK(); 361 error = sysctl_remove_oid_locked(oidp, del, recurse); 362 SYSCTL_XUNLOCK(); 363 return (error); 364 } 365 366 static int 367 sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse) 368 { 369 struct sysctl_oid *p; 370 int error; 371 372 SYSCTL_ASSERT_XLOCKED(); 373 if (oidp == NULL) 374 return(EINVAL); 375 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 376 printf("can't remove non-dynamic nodes!\n"); 377 return (EINVAL); 378 } 379 /* 380 * WARNING: normal method to do this should be through 381 * sysctl_ctx_free(). Use recursing as the last resort 382 * method to purge your sysctl tree of leftovers... 383 * However, if some other code still references these nodes, 384 * it will panic. 385 */ 386 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 387 if (oidp->oid_refcnt == 1) { 388 SLIST_FOREACH(p, SYSCTL_CHILDREN(oidp), oid_link) { 389 if (!recurse) 390 return (ENOTEMPTY); 391 error = sysctl_remove_oid_locked(p, del, 392 recurse); 393 if (error) 394 return (error); 395 } 396 if (del) 397 free(SYSCTL_CHILDREN(oidp), M_SYSCTLOID); 398 } 399 } 400 if (oidp->oid_refcnt > 1 ) { 401 oidp->oid_refcnt--; 402 } else { 403 if (oidp->oid_refcnt == 0) { 404 printf("Warning: bad oid_refcnt=%u (%s)!\n", 405 oidp->oid_refcnt, oidp->oid_name); 406 return (EINVAL); 407 } 408 sysctl_unregister_oid(oidp); 409 if (del) { 410 if (oidp->oid_descr) 411 free((void *)(uintptr_t)(const void *)oidp->oid_descr, M_SYSCTLOID); 412 free((void *)(uintptr_t)(const void *)oidp->oid_name, 413 M_SYSCTLOID); 414 free(oidp, M_SYSCTLOID); 415 } 416 } 417 return (0); 418 } 419 420 /* 421 * Create new sysctls at run time. 422 * clist may point to a valid context initialized with sysctl_ctx_init(). 423 */ 424 struct sysctl_oid * 425 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 426 int number, const char *name, int kind, void *arg1, int arg2, 427 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr) 428 { 429 struct sysctl_oid *oidp; 430 ssize_t len; 431 char *newname; 432 433 /* You have to hook up somewhere.. */ 434 if (parent == NULL) 435 return(NULL); 436 /* Check if the node already exists, otherwise create it */ 437 SYSCTL_XLOCK(); 438 oidp = sysctl_find_oidname(name, parent); 439 if (oidp != NULL) { 440 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 441 oidp->oid_refcnt++; 442 /* Update the context */ 443 if (clist != NULL) 444 sysctl_ctx_entry_add(clist, oidp); 445 SYSCTL_XUNLOCK(); 446 return (oidp); 447 } else { 448 SYSCTL_XUNLOCK(); 449 printf("can't re-use a leaf (%s)!\n", name); 450 return (NULL); 451 } 452 } 453 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK|M_ZERO); 454 oidp->oid_parent = parent; 455 SLIST_NEXT(oidp, oid_link) = NULL; 456 oidp->oid_number = number; 457 oidp->oid_refcnt = 1; 458 len = strlen(name); 459 newname = malloc(len + 1, M_SYSCTLOID, M_WAITOK); 460 bcopy(name, newname, len + 1); 461 newname[len] = '\0'; 462 oidp->oid_name = newname; 463 oidp->oid_handler = handler; 464 oidp->oid_kind = CTLFLAG_DYN | kind; 465 if ((kind & CTLTYPE) == CTLTYPE_NODE) { 466 /* Allocate space for children */ 467 SYSCTL_CHILDREN_SET(oidp, malloc(sizeof(struct sysctl_oid_list), 468 M_SYSCTLOID, M_WAITOK)); 469 SLIST_INIT(SYSCTL_CHILDREN(oidp)); 470 } else { 471 oidp->oid_arg1 = arg1; 472 oidp->oid_arg2 = arg2; 473 } 474 oidp->oid_fmt = fmt; 475 if (descr) { 476 int len = strlen(descr) + 1; 477 oidp->oid_descr = malloc(len, M_SYSCTLOID, M_WAITOK); 478 if (oidp->oid_descr) 479 strcpy((char *)(uintptr_t)(const void *)oidp->oid_descr, descr); 480 } 481 /* Update the context, if used */ 482 if (clist != NULL) 483 sysctl_ctx_entry_add(clist, oidp); 484 /* Register this oid */ 485 sysctl_register_oid(oidp); 486 SYSCTL_XUNLOCK(); 487 return (oidp); 488 } 489 490 /* 491 * Rename an existing oid. 492 */ 493 void 494 sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) 495 { 496 ssize_t len; 497 char *newname; 498 void *oldname; 499 500 len = strlen(name); 501 newname = malloc(len + 1, M_SYSCTLOID, M_WAITOK); 502 bcopy(name, newname, len + 1); 503 newname[len] = '\0'; 504 SYSCTL_XLOCK(); 505 oldname = (void *)(uintptr_t)(const void *)oidp->oid_name; 506 oidp->oid_name = newname; 507 SYSCTL_XUNLOCK(); 508 free(oldname, M_SYSCTLOID); 509 } 510 511 /* 512 * Reparent an existing oid. 513 */ 514 int 515 sysctl_move_oid(struct sysctl_oid *oid, struct sysctl_oid_list *parent) 516 { 517 struct sysctl_oid *oidp; 518 519 SYSCTL_XLOCK(); 520 if (oid->oid_parent == parent) { 521 SYSCTL_XUNLOCK(); 522 return (0); 523 } 524 oidp = sysctl_find_oidname(oid->oid_name, parent); 525 if (oidp != NULL) { 526 SYSCTL_XUNLOCK(); 527 return (EEXIST); 528 } 529 sysctl_unregister_oid(oid); 530 oid->oid_parent = parent; 531 oid->oid_number = OID_AUTO; 532 sysctl_register_oid(oid); 533 SYSCTL_XUNLOCK(); 534 return (0); 535 } 536 537 /* 538 * Register the kernel's oids on startup. 539 */ 540 SET_DECLARE(sysctl_set, struct sysctl_oid); 541 542 static void 543 sysctl_register_all(void *arg) 544 { 545 struct sysctl_oid **oidp; 546 547 sx_init(&sysctlmemlock, "sysctl mem"); 548 SYSCTL_INIT(); 549 SYSCTL_XLOCK(); 550 SET_FOREACH(oidp, sysctl_set) 551 sysctl_register_oid(*oidp); 552 SYSCTL_XUNLOCK(); 553 } 554 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_ANY, sysctl_register_all, 0); 555 556 /* 557 * "Staff-functions" 558 * 559 * These functions implement a presently undocumented interface 560 * used by the sysctl program to walk the tree, and get the type 561 * so it can print the value. 562 * This interface is under work and consideration, and should probably 563 * be killed with a big axe by the first person who can find the time. 564 * (be aware though, that the proper interface isn't as obvious as it 565 * may seem, there are various conflicting requirements. 566 * 567 * {0,0} printf the entire MIB-tree. 568 * {0,1,...} return the name of the "..." OID. 569 * {0,2,...} return the next OID. 570 * {0,3} return the OID of the name in "new" 571 * {0,4,...} return the kind & format info for the "..." OID. 572 * {0,5,...} return the description the "..." OID. 573 */ 574 575 #ifdef SYSCTL_DEBUG 576 static void 577 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 578 { 579 int k; 580 struct sysctl_oid *oidp; 581 582 SYSCTL_ASSERT_LOCKED(); 583 SLIST_FOREACH(oidp, l, oid_link) { 584 585 for (k=0; k<i; k++) 586 printf(" "); 587 588 printf("%d %s ", oidp->oid_number, oidp->oid_name); 589 590 printf("%c%c", 591 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 592 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 593 594 if (oidp->oid_handler) 595 printf(" *Handler"); 596 597 switch (oidp->oid_kind & CTLTYPE) { 598 case CTLTYPE_NODE: 599 printf(" Node\n"); 600 if (!oidp->oid_handler) { 601 sysctl_sysctl_debug_dump_node( 602 oidp->oid_arg1, i+2); 603 } 604 break; 605 case CTLTYPE_INT: printf(" Int\n"); break; 606 case CTLTYPE_STRING: printf(" String\n"); break; 607 case CTLTYPE_QUAD: printf(" Quad\n"); break; 608 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; 609 default: printf("\n"); 610 } 611 612 } 613 } 614 615 static int 616 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 617 { 618 int error; 619 620 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 621 if (error) 622 return (error); 623 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 624 return (ENOENT); 625 } 626 627 SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD, 628 0, 0, sysctl_sysctl_debug, "-", ""); 629 #endif 630 631 static int 632 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 633 { 634 int *name = (int *) arg1; 635 u_int namelen = arg2; 636 int error = 0; 637 struct sysctl_oid *oid; 638 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 639 char buf[10]; 640 641 SYSCTL_ASSERT_LOCKED(); 642 while (namelen) { 643 if (!lsp) { 644 snprintf(buf,sizeof(buf),"%d",*name); 645 if (req->oldidx) 646 error = SYSCTL_OUT(req, ".", 1); 647 if (!error) 648 error = SYSCTL_OUT(req, buf, strlen(buf)); 649 if (error) 650 return (error); 651 namelen--; 652 name++; 653 continue; 654 } 655 lsp2 = 0; 656 SLIST_FOREACH(oid, lsp, oid_link) { 657 if (oid->oid_number != *name) 658 continue; 659 660 if (req->oldidx) 661 error = SYSCTL_OUT(req, ".", 1); 662 if (!error) 663 error = SYSCTL_OUT(req, oid->oid_name, 664 strlen(oid->oid_name)); 665 if (error) 666 return (error); 667 668 namelen--; 669 name++; 670 671 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 672 break; 673 674 if (oid->oid_handler) 675 break; 676 677 lsp2 = (struct sysctl_oid_list *)oid->oid_arg1; 678 break; 679 } 680 lsp = lsp2; 681 } 682 return (SYSCTL_OUT(req, "", 1)); 683 } 684 685 static SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD, sysctl_sysctl_name, ""); 686 687 static int 688 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 689 int *next, int *len, int level, struct sysctl_oid **oidpp) 690 { 691 struct sysctl_oid *oidp; 692 693 SYSCTL_ASSERT_LOCKED(); 694 *len = level; 695 SLIST_FOREACH(oidp, lsp, oid_link) { 696 *next = oidp->oid_number; 697 *oidpp = oidp; 698 699 if (oidp->oid_kind & CTLFLAG_SKIP) 700 continue; 701 702 if (!namelen) { 703 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 704 return (0); 705 if (oidp->oid_handler) 706 /* We really should call the handler here...*/ 707 return (0); 708 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 709 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 710 len, level+1, oidpp)) 711 return (0); 712 goto emptynode; 713 } 714 715 if (oidp->oid_number < *name) 716 continue; 717 718 if (oidp->oid_number > *name) { 719 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 720 return (0); 721 if (oidp->oid_handler) 722 return (0); 723 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 724 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 725 next+1, len, level+1, oidpp)) 726 return (0); 727 goto next; 728 } 729 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 730 continue; 731 732 if (oidp->oid_handler) 733 continue; 734 735 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 736 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 737 len, level+1, oidpp)) 738 return (0); 739 next: 740 namelen = 1; 741 emptynode: 742 *len = level; 743 } 744 return (1); 745 } 746 747 static int 748 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 749 { 750 int *name = (int *) arg1; 751 u_int namelen = arg2; 752 int i, j, error; 753 struct sysctl_oid *oid; 754 struct sysctl_oid_list *lsp = &sysctl__children; 755 int newoid[CTL_MAXNAME]; 756 757 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 758 if (i) 759 return (ENOENT); 760 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 761 return (error); 762 } 763 764 static SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD, sysctl_sysctl_next, ""); 765 766 static int 767 name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) 768 { 769 int i; 770 struct sysctl_oid *oidp; 771 struct sysctl_oid_list *lsp = &sysctl__children; 772 char *p; 773 774 SYSCTL_ASSERT_LOCKED(); 775 776 if (!*name) 777 return (ENOENT); 778 779 p = name + strlen(name) - 1 ; 780 if (*p == '.') 781 *p = '\0'; 782 783 *len = 0; 784 785 for (p = name; *p && *p != '.'; p++) 786 ; 787 i = *p; 788 if (i == '.') 789 *p = '\0'; 790 791 oidp = SLIST_FIRST(lsp); 792 793 while (oidp && *len < CTL_MAXNAME) { 794 if (strcmp(name, oidp->oid_name)) { 795 oidp = SLIST_NEXT(oidp, oid_link); 796 continue; 797 } 798 *oid++ = oidp->oid_number; 799 (*len)++; 800 801 if (!i) { 802 if (oidpp) 803 *oidpp = oidp; 804 return (0); 805 } 806 807 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 808 break; 809 810 if (oidp->oid_handler) 811 break; 812 813 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 814 oidp = SLIST_FIRST(lsp); 815 name = p+1; 816 for (p = name; *p && *p != '.'; p++) 817 ; 818 i = *p; 819 if (i == '.') 820 *p = '\0'; 821 } 822 return (ENOENT); 823 } 824 825 static int 826 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 827 { 828 char *p; 829 int error, oid[CTL_MAXNAME], len; 830 struct sysctl_oid *op = 0; 831 832 SYSCTL_ASSERT_LOCKED(); 833 834 if (!req->newlen) 835 return (ENOENT); 836 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 837 return (ENAMETOOLONG); 838 839 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); 840 841 error = SYSCTL_IN(req, p, req->newlen); 842 if (error) { 843 free(p, M_SYSCTL); 844 return (error); 845 } 846 847 p [req->newlen] = '\0'; 848 849 error = name2oid(p, oid, &len, &op); 850 851 free(p, M_SYSCTL); 852 853 if (error) 854 return (error); 855 856 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 857 return (error); 858 } 859 860 SYSCTL_PROC(_sysctl, 3, name2oid, CTLFLAG_RW|CTLFLAG_ANYBODY|CTLFLAG_MPSAFE, 861 0, 0, sysctl_sysctl_name2oid, "I", ""); 862 863 static int 864 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 865 { 866 struct sysctl_oid *oid; 867 int error; 868 869 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 870 if (error) 871 return (error); 872 873 if (!oid->oid_fmt) 874 return (ENOENT); 875 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 876 if (error) 877 return (error); 878 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 879 return (error); 880 } 881 882 883 static SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD|CTLFLAG_MPSAFE, 884 sysctl_sysctl_oidfmt, ""); 885 886 static int 887 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 888 { 889 struct sysctl_oid *oid; 890 int error; 891 892 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 893 if (error) 894 return (error); 895 896 if (!oid->oid_descr) 897 return (ENOENT); 898 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 899 return (error); 900 } 901 902 static SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD, sysctl_sysctl_oiddescr, ""); 903 904 /* 905 * Default "handler" functions. 906 */ 907 908 /* 909 * Handle an int, signed or unsigned. 910 * Two cases: 911 * a variable: point arg1 at it. 912 * a constant: pass it in arg2. 913 */ 914 915 int 916 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 917 { 918 int tmpout, error = 0; 919 920 /* 921 * Attempt to get a coherent snapshot by making a copy of the data. 922 */ 923 if (arg1) 924 tmpout = *(int *)arg1; 925 else 926 tmpout = arg2; 927 error = SYSCTL_OUT(req, &tmpout, sizeof(int)); 928 929 if (error || !req->newptr) 930 return (error); 931 932 if (!arg1) 933 error = EPERM; 934 else 935 error = SYSCTL_IN(req, arg1, sizeof(int)); 936 return (error); 937 } 938 939 #ifdef VIMAGE 940 int 941 sysctl_handle_v_int(SYSCTL_HANDLER_ARGS) 942 { 943 int tmpout, error = 0; 944 945 SYSCTL_RESOLVE_V_ARG1(); 946 947 /* 948 * Attempt to get a coherent snapshot by making a copy of the data. 949 */ 950 tmpout = *(int *)arg1; 951 error = SYSCTL_OUT(req, &tmpout, sizeof(int)); 952 953 if (error || !req->newptr) 954 return (error); 955 956 if (!arg1) 957 error = EPERM; 958 else 959 error = SYSCTL_IN(req, arg1, sizeof(int)); 960 return (error); 961 } 962 #endif 963 964 /* 965 * Based on on sysctl_handle_int() convert milliseconds into ticks. 966 */ 967 968 int 969 sysctl_msec_to_ticks(SYSCTL_HANDLER_ARGS) 970 { 971 int error, s, tt; 972 973 SYSCTL_RESOLVE_V_ARG1(); 974 975 tt = *(int *)arg1; 976 s = (int)((int64_t)tt * 1000 / hz); 977 978 error = sysctl_handle_int(oidp, &s, 0, req); 979 if (error || !req->newptr) 980 return (error); 981 982 tt = (int)((int64_t)s * hz / 1000); 983 if (tt < 1) 984 return (EINVAL); 985 986 *(int *)arg1 = tt; 987 return (0); 988 } 989 990 991 /* 992 * Handle a long, signed or unsigned. arg1 points to it. 993 */ 994 995 int 996 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 997 { 998 int error = 0; 999 long tmplong; 1000 #ifdef SCTL_MASK32 1001 int tmpint; 1002 #endif 1003 1004 /* 1005 * Attempt to get a coherent snapshot by making a copy of the data. 1006 */ 1007 if (!arg1) 1008 return (EINVAL); 1009 tmplong = *(long *)arg1; 1010 #ifdef SCTL_MASK32 1011 if (req->flags & SCTL_MASK32) { 1012 tmpint = tmplong; 1013 error = SYSCTL_OUT(req, &tmpint, sizeof(int)); 1014 } else 1015 #endif 1016 error = SYSCTL_OUT(req, &tmplong, sizeof(long)); 1017 1018 if (error || !req->newptr) 1019 return (error); 1020 1021 #ifdef SCTL_MASK32 1022 if (req->flags & SCTL_MASK32) { 1023 error = SYSCTL_IN(req, &tmpint, sizeof(int)); 1024 *(long *)arg1 = (long)tmpint; 1025 } else 1026 #endif 1027 error = SYSCTL_IN(req, arg1, sizeof(long)); 1028 return (error); 1029 } 1030 1031 /* 1032 * Handle a 64 bit int, signed or unsigned. arg1 points to it. 1033 */ 1034 1035 int 1036 sysctl_handle_quad(SYSCTL_HANDLER_ARGS) 1037 { 1038 int error = 0; 1039 uint64_t tmpout; 1040 1041 /* 1042 * Attempt to get a coherent snapshot by making a copy of the data. 1043 */ 1044 if (!arg1) 1045 return (EINVAL); 1046 tmpout = *(uint64_t *)arg1; 1047 error = SYSCTL_OUT(req, &tmpout, sizeof(uint64_t)); 1048 1049 if (error || !req->newptr) 1050 return (error); 1051 1052 error = SYSCTL_IN(req, arg1, sizeof(uint64_t)); 1053 return (error); 1054 } 1055 1056 /* 1057 * Handle our generic '\0' terminated 'C' string. 1058 * Two cases: 1059 * a variable string: point arg1 at it, arg2 is max length. 1060 * a constant string: point arg1 at it, arg2 is zero. 1061 */ 1062 1063 int 1064 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 1065 { 1066 int error=0; 1067 char *tmparg; 1068 size_t outlen; 1069 1070 /* 1071 * Attempt to get a coherent snapshot by copying to a 1072 * temporary kernel buffer. 1073 */ 1074 retry: 1075 outlen = strlen((char *)arg1)+1; 1076 tmparg = malloc(outlen, M_SYSCTLTMP, M_WAITOK); 1077 1078 if (strlcpy(tmparg, (char *)arg1, outlen) >= outlen) { 1079 free(tmparg, M_SYSCTLTMP); 1080 goto retry; 1081 } 1082 1083 error = SYSCTL_OUT(req, tmparg, outlen); 1084 free(tmparg, M_SYSCTLTMP); 1085 1086 if (error || !req->newptr) 1087 return (error); 1088 1089 if ((req->newlen - req->newidx) >= arg2) { 1090 error = EINVAL; 1091 } else { 1092 arg2 = (req->newlen - req->newidx); 1093 error = SYSCTL_IN(req, arg1, arg2); 1094 ((char *)arg1)[arg2] = '\0'; 1095 } 1096 1097 return (error); 1098 } 1099 1100 #ifdef VIMAGE 1101 int 1102 sysctl_handle_v_string(SYSCTL_HANDLER_ARGS) 1103 { 1104 int error=0; 1105 char *tmparg; 1106 size_t outlen; 1107 1108 SYSCTL_RESOLVE_V_ARG1(); 1109 1110 /* 1111 * Attempt to get a coherent snapshot by copying to a 1112 * temporary kernel buffer. 1113 */ 1114 retry: 1115 outlen = strlen((char *)arg1)+1; 1116 tmparg = malloc(outlen, M_SYSCTLTMP, M_WAITOK); 1117 1118 if (strlcpy(tmparg, (char *)arg1, outlen) >= outlen) { 1119 free(tmparg, M_SYSCTLTMP); 1120 goto retry; 1121 } 1122 1123 error = SYSCTL_OUT(req, tmparg, outlen); 1124 free(tmparg, M_SYSCTLTMP); 1125 1126 if (error || !req->newptr) 1127 return (error); 1128 1129 if ((req->newlen - req->newidx) >= arg2) { 1130 error = EINVAL; 1131 } else { 1132 arg2 = (req->newlen - req->newidx); 1133 error = SYSCTL_IN(req, arg1, arg2); 1134 ((char *)arg1)[arg2] = '\0'; 1135 } 1136 1137 return (error); 1138 } 1139 #endif 1140 1141 /* 1142 * Handle any kind of opaque data. 1143 * arg1 points to it, arg2 is the size. 1144 */ 1145 1146 int 1147 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 1148 { 1149 int error, tries; 1150 u_int generation; 1151 struct sysctl_req req2; 1152 1153 /* 1154 * Attempt to get a coherent snapshot, by using the thread 1155 * pre-emption counter updated from within mi_switch() to 1156 * determine if we were pre-empted during a bcopy() or 1157 * copyout(). Make 3 attempts at doing this before giving up. 1158 * If we encounter an error, stop immediately. 1159 */ 1160 tries = 0; 1161 req2 = *req; 1162 retry: 1163 generation = curthread->td_generation; 1164 error = SYSCTL_OUT(req, arg1, arg2); 1165 if (error) 1166 return (error); 1167 tries++; 1168 if (generation != curthread->td_generation && tries < 3) { 1169 *req = req2; 1170 goto retry; 1171 } 1172 1173 error = SYSCTL_IN(req, arg1, arg2); 1174 1175 return (error); 1176 } 1177 1178 #ifdef VIMAGE 1179 int 1180 sysctl_handle_v_opaque(SYSCTL_HANDLER_ARGS) 1181 { 1182 int error, tries; 1183 u_int generation; 1184 struct sysctl_req req2; 1185 1186 SYSCTL_RESOLVE_V_ARG1(); 1187 1188 tries = 0; 1189 req2 = *req; 1190 retry: 1191 generation = curthread->td_generation; 1192 error = SYSCTL_OUT(req, arg1, arg2); 1193 if (error) 1194 return (error); 1195 tries++; 1196 if (generation != curthread->td_generation && tries < 3) { 1197 *req = req2; 1198 goto retry; 1199 } 1200 1201 error = SYSCTL_IN(req, arg1, arg2); 1202 1203 return (error); 1204 } 1205 #endif 1206 1207 /* 1208 * Transfer functions to/from kernel space. 1209 * XXX: rather untested at this point 1210 */ 1211 static int 1212 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 1213 { 1214 size_t i = 0; 1215 1216 if (req->oldptr) { 1217 i = l; 1218 if (req->oldlen <= req->oldidx) 1219 i = 0; 1220 else 1221 if (i > req->oldlen - req->oldidx) 1222 i = req->oldlen - req->oldidx; 1223 if (i > 0) 1224 bcopy(p, (char *)req->oldptr + req->oldidx, i); 1225 } 1226 req->oldidx += l; 1227 if (req->oldptr && i != l) 1228 return (ENOMEM); 1229 return (0); 1230 } 1231 1232 static int 1233 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 1234 { 1235 if (!req->newptr) 1236 return (0); 1237 if (req->newlen - req->newidx < l) 1238 return (EINVAL); 1239 bcopy((char *)req->newptr + req->newidx, p, l); 1240 req->newidx += l; 1241 return (0); 1242 } 1243 1244 int 1245 kernel_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1246 size_t *oldlenp, void *new, size_t newlen, size_t *retval, int flags) 1247 { 1248 int error = 0; 1249 struct sysctl_req req; 1250 1251 bzero(&req, sizeof req); 1252 1253 req.td = td; 1254 req.flags = flags; 1255 1256 if (oldlenp) { 1257 req.oldlen = *oldlenp; 1258 } 1259 req.validlen = req.oldlen; 1260 1261 if (old) { 1262 req.oldptr= old; 1263 } 1264 1265 if (new != NULL) { 1266 req.newlen = newlen; 1267 req.newptr = new; 1268 } 1269 1270 req.oldfunc = sysctl_old_kernel; 1271 req.newfunc = sysctl_new_kernel; 1272 req.lock = REQ_LOCKED; 1273 1274 SYSCTL_SLOCK(); 1275 error = sysctl_root(0, name, namelen, &req); 1276 SYSCTL_SUNLOCK(); 1277 1278 if (req.lock == REQ_WIRED && req.validlen > 0) 1279 vsunlock(req.oldptr, req.validlen); 1280 1281 if (error && error != ENOMEM) 1282 return (error); 1283 1284 if (retval) { 1285 if (req.oldptr && req.oldidx > req.validlen) 1286 *retval = req.validlen; 1287 else 1288 *retval = req.oldidx; 1289 } 1290 return (error); 1291 } 1292 1293 int 1294 kernel_sysctlbyname(struct thread *td, char *name, void *old, size_t *oldlenp, 1295 void *new, size_t newlen, size_t *retval, int flags) 1296 { 1297 int oid[CTL_MAXNAME]; 1298 size_t oidlen, plen; 1299 int error; 1300 1301 oid[0] = 0; /* sysctl internal magic */ 1302 oid[1] = 3; /* name2oid */ 1303 oidlen = sizeof(oid); 1304 1305 error = kernel_sysctl(td, oid, 2, oid, &oidlen, 1306 (void *)name, strlen(name), &plen, flags); 1307 if (error) 1308 return (error); 1309 1310 error = kernel_sysctl(td, oid, plen / sizeof(int), old, oldlenp, 1311 new, newlen, retval, flags); 1312 return (error); 1313 } 1314 1315 /* 1316 * Transfer function to/from user space. 1317 */ 1318 static int 1319 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1320 { 1321 int error = 0; 1322 size_t i, len, origidx; 1323 1324 origidx = req->oldidx; 1325 req->oldidx += l; 1326 if (req->oldptr == NULL) 1327 return (0); 1328 /* 1329 * If we have not wired the user supplied buffer and we are currently 1330 * holding locks, drop a witness warning, as it's possible that 1331 * write operations to the user page can sleep. 1332 */ 1333 if (req->lock != REQ_WIRED) 1334 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1335 "sysctl_old_user()"); 1336 i = l; 1337 len = req->validlen; 1338 if (len <= origidx) 1339 i = 0; 1340 else { 1341 if (i > len - origidx) 1342 i = len - origidx; 1343 error = copyout(p, (char *)req->oldptr + origidx, i); 1344 } 1345 if (error) 1346 return (error); 1347 if (i < l) 1348 return (ENOMEM); 1349 return (0); 1350 } 1351 1352 static int 1353 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1354 { 1355 int error; 1356 1357 if (!req->newptr) 1358 return (0); 1359 if (req->newlen - req->newidx < l) 1360 return (EINVAL); 1361 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, 1362 "sysctl_new_user()"); 1363 error = copyin((char *)req->newptr + req->newidx, p, l); 1364 req->newidx += l; 1365 return (error); 1366 } 1367 1368 /* 1369 * Wire the user space destination buffer. If set to a value greater than 1370 * zero, the len parameter limits the maximum amount of wired memory. 1371 */ 1372 int 1373 sysctl_wire_old_buffer(struct sysctl_req *req, size_t len) 1374 { 1375 int ret; 1376 size_t wiredlen; 1377 1378 wiredlen = (len > 0 && len < req->oldlen) ? len : req->oldlen; 1379 ret = 0; 1380 if (req->lock == REQ_LOCKED && req->oldptr && 1381 req->oldfunc == sysctl_old_user) { 1382 if (wiredlen != 0) { 1383 ret = vslock(req->oldptr, wiredlen); 1384 if (ret != 0) { 1385 if (ret != ENOMEM) 1386 return (ret); 1387 wiredlen = 0; 1388 } 1389 } 1390 req->lock = REQ_WIRED; 1391 req->validlen = wiredlen; 1392 } 1393 return (0); 1394 } 1395 1396 int 1397 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 1398 int *nindx, struct sysctl_req *req) 1399 { 1400 struct sysctl_oid *oid; 1401 int indx; 1402 1403 SYSCTL_ASSERT_LOCKED(); 1404 oid = SLIST_FIRST(&sysctl__children); 1405 indx = 0; 1406 while (oid && indx < CTL_MAXNAME) { 1407 if (oid->oid_number == name[indx]) { 1408 indx++; 1409 if (oid->oid_kind & CTLFLAG_NOLOCK) 1410 req->lock = REQ_UNLOCKED; 1411 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1412 if (oid->oid_handler != NULL || 1413 indx == namelen) { 1414 *noid = oid; 1415 if (nindx != NULL) 1416 *nindx = indx; 1417 return (0); 1418 } 1419 oid = SLIST_FIRST( 1420 (struct sysctl_oid_list *)oid->oid_arg1); 1421 } else if (indx == namelen) { 1422 *noid = oid; 1423 if (nindx != NULL) 1424 *nindx = indx; 1425 return (0); 1426 } else { 1427 return (ENOTDIR); 1428 } 1429 } else { 1430 oid = SLIST_NEXT(oid, oid_link); 1431 } 1432 } 1433 return (ENOENT); 1434 } 1435 1436 /* 1437 * Traverse our tree, and find the right node, execute whatever it points 1438 * to, and return the resulting error code. 1439 */ 1440 1441 static int 1442 sysctl_root(SYSCTL_HANDLER_ARGS) 1443 { 1444 struct sysctl_oid *oid; 1445 int error, indx, lvl; 1446 1447 SYSCTL_ASSERT_LOCKED(); 1448 1449 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 1450 if (error) 1451 return (error); 1452 1453 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1454 /* 1455 * You can't call a sysctl when it's a node, but has 1456 * no handler. Inform the user that it's a node. 1457 * The indx may or may not be the same as namelen. 1458 */ 1459 if (oid->oid_handler == NULL) 1460 return (EISDIR); 1461 } 1462 1463 /* Is this sysctl writable? */ 1464 if (req->newptr && !(oid->oid_kind & CTLFLAG_WR)) 1465 return (EPERM); 1466 1467 KASSERT(req->td != NULL, ("sysctl_root(): req->td == NULL")); 1468 1469 /* Is this sysctl sensitive to securelevels? */ 1470 if (req->newptr && (oid->oid_kind & CTLFLAG_SECURE)) { 1471 lvl = (oid->oid_kind & CTLMASK_SECURE) >> CTLSHIFT_SECURE; 1472 error = securelevel_gt(req->td->td_ucred, lvl); 1473 if (error) 1474 return (error); 1475 } 1476 1477 /* Is this sysctl writable by only privileged users? */ 1478 if (req->newptr && !(oid->oid_kind & CTLFLAG_ANYBODY)) { 1479 if (oid->oid_kind & CTLFLAG_PRISON) 1480 error = priv_check(req->td, PRIV_SYSCTL_WRITEJAIL); 1481 else 1482 error = priv_check(req->td, PRIV_SYSCTL_WRITE); 1483 if (error) 1484 return (error); 1485 } 1486 1487 if (!oid->oid_handler) 1488 return (EINVAL); 1489 1490 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1491 arg1 = (int *)arg1 + indx; 1492 arg2 -= indx; 1493 } else { 1494 arg1 = oid->oid_arg1; 1495 arg2 = oid->oid_arg2; 1496 } 1497 #ifdef MAC 1498 error = mac_system_check_sysctl(req->td->td_ucred, oid, arg1, arg2, 1499 req); 1500 if (error != 0) 1501 return (error); 1502 #endif 1503 if (!(oid->oid_kind & CTLFLAG_MPSAFE)) 1504 mtx_lock(&Giant); 1505 error = oid->oid_handler(oid, arg1, arg2, req); 1506 if (!(oid->oid_kind & CTLFLAG_MPSAFE)) 1507 mtx_unlock(&Giant); 1508 1509 return (error); 1510 } 1511 1512 #ifndef _SYS_SYSPROTO_H_ 1513 struct sysctl_args { 1514 int *name; 1515 u_int namelen; 1516 void *old; 1517 size_t *oldlenp; 1518 void *new; 1519 size_t newlen; 1520 }; 1521 #endif 1522 int 1523 __sysctl(struct thread *td, struct sysctl_args *uap) 1524 { 1525 int error, i, name[CTL_MAXNAME]; 1526 size_t j; 1527 1528 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 1529 return (EINVAL); 1530 1531 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 1532 if (error) 1533 return (error); 1534 1535 error = userland_sysctl(td, name, uap->namelen, 1536 uap->old, uap->oldlenp, 0, 1537 uap->new, uap->newlen, &j, 0); 1538 if (error && error != ENOMEM) 1539 return (error); 1540 if (uap->oldlenp) { 1541 i = copyout(&j, uap->oldlenp, sizeof(j)); 1542 if (i) 1543 return (i); 1544 } 1545 return (error); 1546 } 1547 1548 /* 1549 * This is used from various compatibility syscalls too. That's why name 1550 * must be in kernel space. 1551 */ 1552 int 1553 userland_sysctl(struct thread *td, int *name, u_int namelen, void *old, 1554 size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval, 1555 int flags) 1556 { 1557 int error = 0, memlocked; 1558 struct sysctl_req req; 1559 1560 bzero(&req, sizeof req); 1561 1562 req.td = td; 1563 req.flags = flags; 1564 1565 if (oldlenp) { 1566 if (inkernel) { 1567 req.oldlen = *oldlenp; 1568 } else { 1569 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 1570 if (error) 1571 return (error); 1572 } 1573 } 1574 req.validlen = req.oldlen; 1575 1576 if (old) { 1577 if (!useracc(old, req.oldlen, VM_PROT_WRITE)) 1578 return (EFAULT); 1579 req.oldptr= old; 1580 } 1581 1582 if (new != NULL) { 1583 if (!useracc(new, newlen, VM_PROT_READ)) 1584 return (EFAULT); 1585 req.newlen = newlen; 1586 req.newptr = new; 1587 } 1588 1589 req.oldfunc = sysctl_old_user; 1590 req.newfunc = sysctl_new_user; 1591 req.lock = REQ_LOCKED; 1592 1593 #ifdef KTRACE 1594 if (KTRPOINT(curthread, KTR_SYSCTL)) 1595 ktrsysctl(name, namelen); 1596 #endif 1597 1598 if (req.oldlen > PAGE_SIZE) { 1599 memlocked = 1; 1600 sx_xlock(&sysctlmemlock); 1601 } else 1602 memlocked = 0; 1603 CURVNET_SET(TD_TO_VNET(td)); 1604 1605 for (;;) { 1606 req.oldidx = 0; 1607 req.newidx = 0; 1608 SYSCTL_SLOCK(); 1609 error = sysctl_root(0, name, namelen, &req); 1610 SYSCTL_SUNLOCK(); 1611 if (error != EAGAIN) 1612 break; 1613 uio_yield(); 1614 } 1615 1616 CURVNET_RESTORE(); 1617 1618 if (req.lock == REQ_WIRED && req.validlen > 0) 1619 vsunlock(req.oldptr, req.validlen); 1620 if (memlocked) 1621 sx_xunlock(&sysctlmemlock); 1622 1623 if (error && error != ENOMEM) 1624 return (error); 1625 1626 if (retval) { 1627 if (req.oldptr && req.oldidx > req.validlen) 1628 *retval = req.validlen; 1629 else 1630 *retval = req.oldidx; 1631 } 1632 return (error); 1633 } 1634