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 * $FreeBSD: src/sys/kern/kern_sysctl.c,v 1.92.2.9 2003/05/01 22:48:09 trhodes Exp $ 37 */ 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/kernel.h> 42 #include <sys/buf.h> 43 #include <sys/sysctl.h> 44 #include <sys/malloc.h> 45 #include <sys/proc.h> 46 #include <sys/priv.h> 47 #include <sys/sysproto.h> 48 #include <sys/lock.h> 49 50 #include <sys/mplock2.h> 51 52 #include <vm/vm.h> 53 #include <vm/vm_extern.h> 54 55 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic"); 56 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids"); 57 58 static struct lock sysctl_lkp; 59 static struct lock sysctl_ctx_lkp; 60 61 static void sysctl_lock(int type); 62 static void sysctl_unlock(void); 63 static void sysctl_ctx_lock(int type); 64 static void sysctl_ctx_unlock(void); 65 66 static int sysctl_root(SYSCTL_HANDLER_ARGS); 67 static void sysctl_register_oid_int(struct sysctl_oid *oipd); 68 static void sysctl_unregister_oid_int(struct sysctl_oid *oipd); 69 static struct sysctl_ctx_entry* sysctl_ctx_entry_find_int 70 (struct sysctl_ctx_list *, struct sysctl_oid *oidp); 71 72 struct sysctl_oid_list sysctl__children; /* root list */ 73 74 static struct sysctl_oid * 75 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list, int lock) 76 { 77 struct sysctl_oid *oidp; 78 79 SLIST_FOREACH(oidp, list, oid_link) { 80 if (strcmp(oidp->oid_name, name) == 0) { 81 break; 82 } 83 } 84 return (oidp); 85 } 86 87 /* 88 * Initialization of the MIB tree. 89 * 90 * Order by number in each list. 91 */ 92 93 void 94 sysctl_register_oid(struct sysctl_oid *oidp) 95 { 96 sysctl_lock(LK_EXCLUSIVE); 97 sysctl_register_oid_int(oidp); 98 sysctl_unlock(); 99 } 100 101 static void 102 sysctl_register_oid_int(struct sysctl_oid *oidp) 103 { 104 struct sysctl_oid_list *parent = oidp->oid_parent; 105 struct sysctl_oid *p; 106 struct sysctl_oid *q; 107 108 /* 109 * First check if another oid with the same name already 110 * exists in the parent's list. 111 */ 112 p = sysctl_find_oidname(oidp->oid_name, parent, 0); 113 if (p != NULL) { 114 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) 115 p->oid_refcnt++; 116 else 117 kprintf("can't re-use a leaf (%s)!\n", p->oid_name); 118 return; 119 } 120 121 /* 122 * If this oid has a number OID_AUTO, give it a number which 123 * is greater than any current oid. Make sure it is at least 124 * 256 to leave space for pre-assigned oid numbers. 125 */ 126 if (oidp->oid_number == OID_AUTO) { 127 int newoid = 0x100; /* minimum AUTO oid */ 128 129 /* 130 * Adjust based on highest oid in parent list 131 */ 132 SLIST_FOREACH(p, parent, oid_link) { 133 if (newoid <= p->oid_number) 134 newoid = p->oid_number + 1; 135 } 136 oidp->oid_number = newoid; 137 } 138 139 /* 140 * Insert the oid into the parent's list in order. 141 */ 142 q = NULL; 143 SLIST_FOREACH(p, parent, oid_link) { 144 if (oidp->oid_number < p->oid_number) 145 break; 146 q = p; 147 } 148 if (q) 149 SLIST_INSERT_AFTER(q, oidp, oid_link); 150 else 151 SLIST_INSERT_HEAD(parent, oidp, oid_link); 152 } 153 154 void 155 sysctl_unregister_oid(struct sysctl_oid *oidp) 156 { 157 sysctl_lock(LK_EXCLUSIVE); 158 sysctl_unregister_oid_int(oidp); 159 sysctl_unlock(); 160 } 161 162 static void 163 sysctl_unregister_oid_int(struct sysctl_oid *oidp) 164 { 165 struct sysctl_oid *p; 166 167 if (oidp->oid_number == OID_AUTO) 168 panic("Trying to unregister OID_AUTO entry: %p", oidp); 169 170 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 171 if (p != oidp) 172 continue; 173 SLIST_REMOVE(oidp->oid_parent, oidp, sysctl_oid, oid_link); 174 return; 175 } 176 177 /* 178 * This can happen when a module fails to register and is 179 * being unloaded afterwards. It should not be a panic() 180 * for normal use. 181 */ 182 kprintf("%s: failed to unregister sysctl\n", __func__); 183 } 184 185 /* Initialize a new context to keep track of dynamically added sysctls. */ 186 int 187 sysctl_ctx_init(struct sysctl_ctx_list *c) 188 { 189 if (c == NULL) 190 return(EINVAL); 191 TAILQ_INIT(c); 192 return(0); 193 } 194 195 /* Free the context, and destroy all dynamic oids registered in this context */ 196 int 197 sysctl_ctx_free(struct sysctl_ctx_list *clist) 198 { 199 struct sysctl_ctx_entry *e, *e1; 200 int error; 201 202 error = 0; 203 sysctl_ctx_lock(LK_EXCLUSIVE); 204 /* 205 * First perform a "dry run" to check if it's ok to remove oids. 206 * XXX FIXME 207 * XXX This algorithm is a hack. But I don't know any 208 * XXX better solution for now... 209 */ 210 TAILQ_FOREACH(e, clist, link) { 211 error = sysctl_remove_oid(e->entry, 0, 0); 212 if (error) 213 break; 214 } 215 /* 216 * Restore deregistered entries, either from the end, 217 * or from the place where error occured. 218 * e contains the entry that was not unregistered 219 */ 220 if (error) 221 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 222 else 223 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 224 while (e1 != NULL) { 225 sysctl_register_oid(e1->entry); 226 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 227 } 228 if (error) { 229 sysctl_ctx_unlock(); 230 return(EBUSY); 231 } 232 /* Now really delete the entries */ 233 e = TAILQ_FIRST(clist); 234 while (e != NULL) { 235 e1 = TAILQ_NEXT(e, link); 236 error = sysctl_remove_oid(e->entry, 1, 0); 237 if (error) 238 panic("sysctl_remove_oid: corrupt tree, entry: %s", 239 e->entry->oid_name); 240 kfree(e, M_SYSCTLOID); 241 e = e1; 242 } 243 sysctl_ctx_unlock(); 244 return (error); 245 } 246 247 /* Add an entry to the context */ 248 struct sysctl_ctx_entry * 249 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 250 { 251 struct sysctl_ctx_entry *e; 252 253 if (clist == NULL || oidp == NULL) 254 return(NULL); 255 e = kmalloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 256 e->entry = oidp; 257 sysctl_ctx_lock(LK_EXCLUSIVE); 258 TAILQ_INSERT_HEAD(clist, e, link); 259 sysctl_ctx_unlock(); 260 return (e); 261 } 262 263 /* Find an entry in the context */ 264 struct sysctl_ctx_entry * 265 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 266 { 267 struct sysctl_ctx_entry *e; 268 269 if (clist == NULL || oidp == NULL) 270 return(NULL); 271 272 sysctl_ctx_lock(LK_SHARED); 273 e = sysctl_ctx_entry_find_int(clist, oidp); 274 sysctl_ctx_unlock(); 275 276 return(e); 277 } 278 279 struct sysctl_ctx_entry * 280 sysctl_ctx_entry_find_int(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 281 { 282 struct sysctl_ctx_entry *e; 283 284 KKASSERT(clist != NULL && oidp != NULL); 285 286 for (e = TAILQ_FIRST(clist); e != NULL; e = TAILQ_NEXT(e, link)) { 287 if(e->entry == oidp) 288 break; 289 } 290 291 return (e); 292 } 293 294 /* 295 * Delete an entry from the context. 296 * NOTE: this function doesn't free oidp! You have to remove it 297 * with sysctl_remove_oid(). 298 */ 299 int 300 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 301 { 302 struct sysctl_ctx_entry *e; 303 304 if (clist == NULL || oidp == NULL) 305 return (EINVAL); 306 307 sysctl_ctx_lock(LK_EXCLUSIVE); 308 e = sysctl_ctx_entry_find_int(clist, oidp); 309 if (e == NULL) { 310 sysctl_ctx_unlock(); 311 return (ENOENT); 312 } 313 TAILQ_REMOVE(clist, e, link); 314 kfree(e, M_SYSCTLOID); 315 sysctl_ctx_unlock(); 316 317 return(0); 318 } 319 320 /* 321 * Remove dynamically created sysctl trees. 322 * oidp - top of the tree to be removed 323 * del - if 0 - just deregister, otherwise free up entries as well 324 * recurse - if != 0 traverse the subtree to be deleted 325 */ 326 int 327 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 328 { 329 struct sysctl_oid *p; 330 int error; 331 332 if (oidp == NULL) 333 return(EINVAL); 334 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 335 kprintf("can't remove non-dynamic nodes!\n"); 336 return (EINVAL); 337 } 338 sysctl_lock(LK_EXCLUSIVE | LK_CANRECURSE); 339 /* 340 * WARNING: normal method to do this should be through 341 * sysctl_ctx_free(). Use recursing as the last resort 342 * method to purge your sysctl tree of leftovers... 343 * However, if some other code still references these nodes, 344 * it will panic. 345 */ 346 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 347 if (oidp->oid_refcnt == 1) { 348 SLIST_FOREACH(p, SYSCTL_CHILDREN(oidp), oid_link) { 349 if (!recurse) { 350 sysctl_unlock(); 351 return(ENOTEMPTY); 352 } 353 error = sysctl_remove_oid(p, del, recurse); 354 if (error) { 355 sysctl_unlock(); 356 return(error); 357 } 358 } 359 if (del) 360 kfree(SYSCTL_CHILDREN(oidp), M_SYSCTLOID); 361 } 362 } 363 if (oidp->oid_refcnt > 1 ) { 364 oidp->oid_refcnt--; 365 } else { 366 if (oidp->oid_refcnt == 0) { 367 kprintf("Warning: bad oid_refcnt=%u (%s)!\n", 368 oidp->oid_refcnt, oidp->oid_name); 369 sysctl_unlock(); 370 return(EINVAL); 371 } 372 sysctl_unregister_oid_int(oidp); 373 if (del) { 374 if (oidp->oid_descr) 375 kfree(__DECONST(char *,oidp->oid_descr), 376 M_SYSCTLOID); 377 kfree(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); 378 kfree(oidp, M_SYSCTLOID); 379 } 380 } 381 sysctl_unlock(); 382 return(0); 383 } 384 385 /* 386 * Create new sysctls at run time. 387 * clist may point to a valid context initialized with sysctl_ctx_init(). 388 */ 389 struct sysctl_oid * 390 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 391 int number, const char *name, int kind, void *arg1, int arg2, 392 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr) 393 { 394 struct sysctl_oid *oidp; 395 ssize_t len; 396 char *newname; 397 398 /* You have to hook up somewhere.. */ 399 if (parent == NULL) 400 return(NULL); 401 sysctl_lock(LK_EXCLUSIVE); 402 /* Check if the node already exists, otherwise create it */ 403 oidp = sysctl_find_oidname(name, parent, 0); 404 if (oidp != NULL) { 405 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 406 oidp->oid_refcnt++; 407 /* Update the context */ 408 if (clist != NULL) 409 sysctl_ctx_entry_add(clist, oidp); 410 sysctl_unlock(); 411 return (oidp); 412 } else { 413 kprintf("can't re-use a leaf (%s)!\n", name); 414 sysctl_unlock(); 415 return (NULL); 416 } 417 } 418 oidp = kmalloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK | M_ZERO); 419 oidp->oid_parent = parent; 420 SLIST_NEXT(oidp, oid_link) = NULL; 421 oidp->oid_number = number; 422 oidp->oid_refcnt = 1; 423 len = strlen(name); 424 newname = kmalloc(len + 1, M_SYSCTLOID, M_WAITOK); 425 bcopy(name, newname, len + 1); 426 newname[len] = '\0'; 427 oidp->oid_name = newname; 428 oidp->oid_handler = handler; 429 oidp->oid_kind = CTLFLAG_DYN | kind; 430 if ((kind & CTLTYPE) == CTLTYPE_NODE) { 431 struct sysctl_oid_list *children; 432 433 /* Allocate space for children */ 434 children = kmalloc(sizeof(*children), M_SYSCTLOID, M_WAITOK); 435 SYSCTL_SET_CHILDREN(oidp, children); 436 SLIST_INIT(children); 437 } else { 438 oidp->oid_arg1 = arg1; 439 oidp->oid_arg2 = arg2; 440 } 441 oidp->oid_fmt = fmt; 442 if (descr) { 443 int len = strlen(descr) + 1; 444 oidp->oid_descr = kmalloc(len, M_SYSCTLOID, M_WAITOK); 445 strcpy((char *)(uintptr_t)(const void *)oidp->oid_descr, descr); 446 }; 447 /* Update the context, if used */ 448 if (clist != NULL) 449 sysctl_ctx_entry_add(clist, oidp); 450 /* Register this oid */ 451 sysctl_register_oid_int(oidp); 452 sysctl_unlock(); 453 return (oidp); 454 } 455 456 /* 457 * Register the kernel's oids on startup. 458 */ 459 SET_DECLARE(sysctl_set, struct sysctl_oid); 460 461 static void 462 sysctl_register_all(void *arg) 463 { 464 struct sysctl_oid **oidp; 465 466 lockinit(&sysctl_lkp, "sysctl", 0, 0); 467 lockinit(&sysctl_ctx_lkp, "sysctl ctx", 0, 0); 468 SET_FOREACH(oidp, sysctl_set) 469 sysctl_register_oid_int(*oidp); 470 } 471 472 SYSINIT(sysctl, SI_BOOT1_POST, SI_ORDER_ANY, sysctl_register_all, 0); 473 474 /* 475 * "Staff-functions" 476 * 477 * These functions implement a presently undocumented interface 478 * used by the sysctl program to walk the tree, and get the type 479 * so it can print the value. 480 * This interface is under work and consideration, and should probably 481 * be killed with a big axe by the first person who can find the time. 482 * (be aware though, that the proper interface isn't as obvious as it 483 * may seem, there are various conflicting requirements. 484 * 485 * {0,0} kprintf the entire MIB-tree. 486 * {0,1,...} return the name of the "..." OID. 487 * {0,2,...} return the next OID. 488 * {0,3} return the OID of the name in "new" 489 * {0,4,...} return the kind & format info for the "..." OID. 490 */ 491 492 static void 493 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 494 { 495 int k; 496 struct sysctl_oid *oidp; 497 498 sysctl_lock(LK_SHARED); 499 SLIST_FOREACH(oidp, l, oid_link) { 500 501 for (k=0; k<i; k++) 502 kprintf(" "); 503 504 kprintf("%d %s ", oidp->oid_number, oidp->oid_name); 505 506 kprintf("%c%c", 507 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 508 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 509 510 if (oidp->oid_handler) 511 kprintf(" *Handler"); 512 513 switch (oidp->oid_kind & CTLTYPE) { 514 case CTLTYPE_NODE: 515 kprintf(" Node\n"); 516 if (!oidp->oid_handler) { 517 sysctl_sysctl_debug_dump_node( 518 oidp->oid_arg1, i+2); 519 } 520 break; 521 case CTLTYPE_INT: kprintf(" Int\n"); break; 522 case CTLTYPE_STRING: kprintf(" String\n"); break; 523 case CTLTYPE_QUAD: kprintf(" Quad\n"); break; 524 case CTLTYPE_OPAQUE: kprintf(" Opaque/struct\n"); break; 525 default: kprintf("\n"); 526 } 527 528 } 529 sysctl_unlock(); 530 } 531 532 static int 533 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 534 { 535 int error; 536 537 error = priv_check(req->td, PRIV_SYSCTL_DEBUG); 538 if (error) 539 return error; 540 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 541 return ENOENT; 542 } 543 544 SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD, 545 0, 0, sysctl_sysctl_debug, "-", ""); 546 547 static int 548 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 549 { 550 int *name = (int *) arg1; 551 u_int namelen = arg2; 552 int error = 0; 553 struct sysctl_oid *oid; 554 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 555 char buf[16]; 556 557 sysctl_lock(LK_SHARED); 558 while (namelen) { 559 if (!lsp) { 560 ksnprintf(buf, sizeof(buf), "%d", *name); 561 if (req->oldidx) 562 error = SYSCTL_OUT(req, ".", 1); 563 if (!error) 564 error = SYSCTL_OUT(req, buf, strlen(buf)); 565 if (error) { 566 sysctl_unlock(); 567 return (error); 568 } 569 namelen--; 570 name++; 571 continue; 572 } 573 lsp2 = NULL; 574 SLIST_FOREACH(oid, lsp, oid_link) { 575 if (oid->oid_number != *name) 576 continue; 577 578 if (req->oldidx) 579 error = SYSCTL_OUT(req, ".", 1); 580 if (!error) 581 error = SYSCTL_OUT(req, oid->oid_name, 582 strlen(oid->oid_name)); 583 if (error) { 584 sysctl_unlock(); 585 return (error); 586 } 587 588 namelen--; 589 name++; 590 591 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 592 break; 593 594 if (oid->oid_handler) 595 break; 596 597 lsp2 = (struct sysctl_oid_list *)oid->oid_arg1; 598 break; 599 } 600 lsp = lsp2; 601 } 602 sysctl_unlock(); 603 return (SYSCTL_OUT(req, "", 1)); 604 } 605 606 SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD, sysctl_sysctl_name, ""); 607 608 static int 609 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 610 int *next, int *len, int level, struct sysctl_oid **oidpp) 611 { 612 struct sysctl_oid *oidp; 613 614 *len = level; 615 sysctl_lock(LK_SHARED); 616 SLIST_FOREACH(oidp, lsp, oid_link) { 617 *next = oidp->oid_number; 618 *oidpp = oidp; 619 620 if (!namelen) { 621 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) { 622 sysctl_unlock(); 623 return 0; 624 } 625 if (oidp->oid_handler) { 626 /* We really should call the handler here...*/ 627 sysctl_unlock(); 628 return 0; 629 } 630 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 631 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 632 len, level+1, oidpp)) { 633 sysctl_unlock(); 634 return 0; 635 } 636 goto emptynode; 637 } 638 639 if (oidp->oid_number < *name) 640 continue; 641 642 if (oidp->oid_number > *name) { 643 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) { 644 sysctl_unlock(); 645 return 0; 646 } 647 if (oidp->oid_handler) { 648 sysctl_unlock(); 649 return 0; 650 } 651 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 652 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 653 next+1, len, level+1, oidpp)) { 654 sysctl_unlock(); 655 return (0); 656 } 657 goto next; 658 } 659 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 660 continue; 661 662 if (oidp->oid_handler) 663 continue; 664 665 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 666 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 667 len, level+1, oidpp)) { 668 sysctl_unlock(); 669 return (0); 670 } 671 next: 672 namelen = 1; 673 *len = level; 674 emptynode: 675 *len = level; 676 } 677 sysctl_unlock(); 678 return 1; 679 } 680 681 static int 682 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 683 { 684 int *name = (int *) arg1; 685 u_int namelen = arg2; 686 int i, j, error; 687 struct sysctl_oid *oid; 688 struct sysctl_oid_list *lsp = &sysctl__children; 689 int newoid[CTL_MAXNAME]; 690 691 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 692 if (i) 693 return ENOENT; 694 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 695 return (error); 696 } 697 698 SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD, sysctl_sysctl_next, ""); 699 700 static int 701 name2oid (char *name, int *oid, int *len, struct sysctl_oid **oidpp) 702 { 703 int i; 704 struct sysctl_oid *oidp; 705 struct sysctl_oid_list *lsp = &sysctl__children; 706 char *p; 707 708 if (!*name) 709 return ENOENT; 710 711 p = name + strlen(name) - 1 ; 712 if (*p == '.') 713 *p = '\0'; 714 715 *len = 0; 716 717 for (p = name; *p && *p != '.'; p++) 718 ; 719 i = *p; 720 if (i == '.') 721 *p = '\0'; 722 723 sysctl_lock(LK_SHARED); 724 oidp = SLIST_FIRST(lsp); 725 726 while (oidp && *len < CTL_MAXNAME) { 727 if (strcmp(name, oidp->oid_name)) { 728 oidp = SLIST_NEXT(oidp, oid_link); 729 continue; 730 } 731 *oid++ = oidp->oid_number; 732 (*len)++; 733 734 if (!i) { 735 if (oidpp) 736 *oidpp = oidp; 737 sysctl_unlock(); 738 return (0); 739 } 740 741 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 742 break; 743 744 if (oidp->oid_handler) 745 break; 746 747 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 748 oidp = SLIST_FIRST(lsp); 749 name = p+1; 750 for (p = name; *p && *p != '.'; p++) 751 ; 752 i = *p; 753 if (i == '.') 754 *p = '\0'; 755 } 756 sysctl_unlock(); 757 return ENOENT; 758 } 759 760 static int 761 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 762 { 763 char *p; 764 int error, oid[CTL_MAXNAME], len; 765 struct sysctl_oid *op = NULL; 766 767 if (!req->newlen) 768 return ENOENT; 769 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 770 return (ENAMETOOLONG); 771 772 p = kmalloc(req->newlen+1, M_SYSCTL, M_WAITOK); 773 774 error = SYSCTL_IN(req, p, req->newlen); 775 if (error) { 776 kfree(p, M_SYSCTL); 777 return (error); 778 } 779 780 p [req->newlen] = '\0'; 781 782 error = name2oid(p, oid, &len, &op); 783 784 kfree(p, M_SYSCTL); 785 786 if (error) 787 return (error); 788 789 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 790 return (error); 791 } 792 793 SYSCTL_PROC(_sysctl, 3, name2oid, CTLFLAG_RW|CTLFLAG_ANYBODY, 0, 0, 794 sysctl_sysctl_name2oid, "I", ""); 795 796 static int 797 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 798 { 799 struct sysctl_oid *oid; 800 int error; 801 802 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 803 if (error) 804 return (error); 805 806 if (!oid->oid_fmt) 807 return (ENOENT); 808 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 809 if (error) 810 return (error); 811 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 812 return (error); 813 } 814 815 816 SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD, sysctl_sysctl_oidfmt, ""); 817 818 static int 819 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 820 { 821 struct sysctl_oid *oid; 822 int error; 823 824 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 825 if (error) 826 return (error); 827 828 if (!oid->oid_descr) 829 return (ENOENT); 830 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 831 return (error); 832 } 833 834 SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD, sysctl_sysctl_oiddescr, ""); 835 836 /* 837 * Default "handler" functions. 838 */ 839 840 /* 841 * Handle an int, signed or unsigned. 842 * Two cases: 843 * a variable: point arg1 at it. 844 * a constant: pass it in arg2. 845 */ 846 847 int 848 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 849 { 850 int error = 0; 851 852 if (arg1) 853 error = SYSCTL_OUT(req, arg1, sizeof(int)); 854 else 855 error = SYSCTL_OUT(req, &arg2, sizeof(int)); 856 857 if (error || !req->newptr) 858 return (error); 859 860 if (!arg1) 861 error = EPERM; 862 else 863 error = SYSCTL_IN(req, arg1, sizeof(int)); 864 return (error); 865 } 866 867 /* 868 * Handle a long, signed or unsigned. arg1 points to it. 869 */ 870 871 int 872 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 873 { 874 int error = 0; 875 876 if (!arg1) 877 return (EINVAL); 878 error = SYSCTL_OUT(req, arg1, sizeof(long)); 879 880 if (error || !req->newptr) 881 return (error); 882 883 error = SYSCTL_IN(req, arg1, sizeof(long)); 884 return (error); 885 } 886 887 /* 888 * Handle a quad, signed or unsigned. arg1 points to it. 889 */ 890 891 int 892 sysctl_handle_quad(SYSCTL_HANDLER_ARGS) 893 { 894 int error = 0; 895 896 if (!arg1) 897 return (EINVAL); 898 error = SYSCTL_OUT(req, arg1, sizeof(quad_t)); 899 900 if (error || !req->newptr) 901 return (error); 902 903 error = SYSCTL_IN(req, arg1, sizeof(quad_t)); 904 return (error); 905 } 906 907 /* 908 * Handle our generic '\0' terminated 'C' string. 909 * Two cases: 910 * a variable string: point arg1 at it, arg2 is max length. 911 * a constant string: point arg1 at it, arg2 is zero. 912 */ 913 914 int 915 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 916 { 917 int error=0; 918 919 error = SYSCTL_OUT(req, arg1, strlen((char *)arg1)+1); 920 921 if (error || !req->newptr) 922 return (error); 923 924 if ((req->newlen - req->newidx) >= arg2) { 925 error = EINVAL; 926 } else { 927 arg2 = (req->newlen - req->newidx); 928 error = SYSCTL_IN(req, arg1, arg2); 929 ((char *)arg1)[arg2] = '\0'; 930 } 931 932 return (error); 933 } 934 935 /* 936 * Handle any kind of opaque data. 937 * arg1 points to it, arg2 is the size. 938 */ 939 940 int 941 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 942 { 943 int error; 944 945 error = SYSCTL_OUT(req, arg1, arg2); 946 947 if (error || !req->newptr) 948 return (error); 949 950 error = SYSCTL_IN(req, arg1, arg2); 951 952 return (error); 953 } 954 955 /* 956 * Transfer functions to/from kernel space. 957 * XXX: rather untested at this point 958 */ 959 static int 960 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 961 { 962 size_t i = 0; 963 964 if (req->oldptr) { 965 i = l; 966 if (i > req->oldlen - req->oldidx) 967 i = req->oldlen - req->oldidx; 968 if (i > 0) 969 bcopy(p, (char *)req->oldptr + req->oldidx, i); 970 } 971 req->oldidx += l; 972 if (req->oldptr && i != l) 973 return (ENOMEM); 974 return (0); 975 } 976 977 static int 978 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 979 { 980 981 if (!req->newptr) 982 return 0; 983 if (req->newlen - req->newidx < l) 984 return (EINVAL); 985 bcopy((char *)req->newptr + req->newidx, p, l); 986 req->newidx += l; 987 return (0); 988 } 989 990 int 991 kernel_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval) 992 { 993 int error = 0; 994 struct sysctl_req req; 995 996 bzero(&req, sizeof req); 997 998 req.td = curthread; 999 1000 if (oldlenp) { 1001 req.oldlen = *oldlenp; 1002 } 1003 1004 if (old) { 1005 req.oldptr = old; 1006 } 1007 1008 if (new != NULL) { 1009 req.newlen = newlen; 1010 req.newptr = new; 1011 } 1012 1013 req.oldfunc = sysctl_old_kernel; 1014 req.newfunc = sysctl_new_kernel; 1015 #if 0 1016 req.lock = 1; 1017 #endif 1018 1019 sysctl_lock(LK_SHARED); 1020 1021 error = sysctl_root(0, name, namelen, &req); 1022 1023 #if 0 1024 if (req.lock == 2) 1025 vsunlock(req.oldptr, req.oldlen); 1026 #endif 1027 1028 sysctl_unlock(); 1029 1030 if (error && error != ENOMEM) 1031 return (error); 1032 1033 if (retval) { 1034 if (req.oldptr && req.oldidx > req.oldlen) 1035 *retval = req.oldlen; 1036 else 1037 *retval = req.oldidx; 1038 } 1039 return (error); 1040 } 1041 1042 int 1043 kernel_sysctlbyname(char *name, void *old, size_t *oldlenp, 1044 void *new, size_t newlen, size_t *retval) 1045 { 1046 int oid[CTL_MAXNAME]; 1047 size_t oidlen, plen; 1048 int error; 1049 1050 oid[0] = 0; /* sysctl internal magic */ 1051 oid[1] = 3; /* name2oid */ 1052 oidlen = sizeof(oid); 1053 1054 error = kernel_sysctl(oid, 2, oid, &oidlen, name, strlen(name), &plen); 1055 if (error) 1056 return (error); 1057 1058 error = kernel_sysctl(oid, plen / sizeof(int), old, oldlenp, 1059 new, newlen, retval); 1060 return (error); 1061 } 1062 1063 /* 1064 * Transfer function to/from user space. 1065 */ 1066 static int 1067 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1068 { 1069 int error = 0; 1070 size_t i = 0; 1071 1072 #if 0 1073 if (req->lock == 1 && req->oldptr) { 1074 vslock(req->oldptr, req->oldlen); 1075 req->lock = 2; 1076 } 1077 #endif 1078 if (req->oldptr) { 1079 i = l; 1080 if (i > req->oldlen - req->oldidx) 1081 i = req->oldlen - req->oldidx; 1082 if (i > 0) 1083 error = copyout(p, (char *)req->oldptr + req->oldidx, 1084 i); 1085 } 1086 req->oldidx += l; 1087 if (error) 1088 return (error); 1089 if (req->oldptr && i < l) 1090 return (ENOMEM); 1091 return (0); 1092 } 1093 1094 static int 1095 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1096 { 1097 int error; 1098 1099 if (!req->newptr) 1100 return 0; 1101 if (req->newlen - req->newidx < l) 1102 return (EINVAL); 1103 error = copyin((char *)req->newptr + req->newidx, p, l); 1104 req->newidx += l; 1105 return (error); 1106 } 1107 1108 int 1109 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 1110 int *nindx, struct sysctl_req *req) 1111 { 1112 struct sysctl_oid *oid; 1113 int indx; 1114 1115 sysctl_lock(LK_SHARED); 1116 oid = SLIST_FIRST(&sysctl__children); 1117 indx = 0; 1118 while (oid && indx < CTL_MAXNAME) { 1119 if (oid->oid_number == name[indx]) { 1120 indx++; 1121 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1122 if (oid->oid_handler != NULL || 1123 indx == namelen) { 1124 *noid = oid; 1125 if (nindx != NULL) 1126 *nindx = indx; 1127 sysctl_unlock(); 1128 return (0); 1129 } 1130 oid = SLIST_FIRST( 1131 (struct sysctl_oid_list *)oid->oid_arg1); 1132 } else if (indx == namelen) { 1133 *noid = oid; 1134 if (nindx != NULL) 1135 *nindx = indx; 1136 sysctl_unlock(); 1137 return (0); 1138 } else { 1139 sysctl_unlock(); 1140 return (ENOTDIR); 1141 } 1142 } else { 1143 oid = SLIST_NEXT(oid, oid_link); 1144 } 1145 } 1146 sysctl_unlock(); 1147 return (ENOENT); 1148 } 1149 1150 /* 1151 * Traverse our tree, and find the right node, execute whatever it points 1152 * to, and return the resulting error code. 1153 */ 1154 1155 int 1156 sysctl_root(SYSCTL_HANDLER_ARGS) 1157 { 1158 struct thread *td = req->td; 1159 struct proc *p = td ? td->td_proc : NULL; 1160 struct sysctl_oid *oid; 1161 int error, indx; 1162 1163 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 1164 if (error) 1165 return (error); 1166 1167 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1168 /* 1169 * You can't call a sysctl when it's a node, but has 1170 * no handler. Inform the user that it's a node. 1171 * The indx may or may not be the same as namelen. 1172 */ 1173 if (oid->oid_handler == NULL) 1174 return (EISDIR); 1175 } 1176 1177 /* If writing isn't allowed */ 1178 if (req->newptr && (!(oid->oid_kind & CTLFLAG_WR) || 1179 ((oid->oid_kind & CTLFLAG_SECURE) && securelevel > 0))) 1180 return (EPERM); 1181 1182 /* Most likely only root can write */ 1183 if (!(oid->oid_kind & CTLFLAG_ANYBODY) && req->newptr && p && 1184 (error = priv_check_cred(td->td_ucred, 1185 (oid->oid_kind & CTLFLAG_PRISON) ? PRIV_SYSCTL_WRITEJAIL : 1186 PRIV_SYSCTL_WRITE, 0))) 1187 return (error); 1188 1189 if (!oid->oid_handler) 1190 return EINVAL; 1191 1192 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) 1193 error = oid->oid_handler(oid, (int *)arg1 + indx, arg2 - indx, 1194 req); 1195 else 1196 error = oid->oid_handler(oid, oid->oid_arg1, oid->oid_arg2, 1197 req); 1198 return (error); 1199 } 1200 1201 /* 1202 * MPALMOSTSAFE 1203 */ 1204 int 1205 sys___sysctl(struct sysctl_args *uap) 1206 { 1207 int error, i, name[CTL_MAXNAME]; 1208 size_t j; 1209 1210 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 1211 return (EINVAL); 1212 1213 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 1214 if (error) 1215 return (error); 1216 1217 error = userland_sysctl(name, uap->namelen, 1218 uap->old, uap->oldlenp, 0, 1219 uap->new, uap->newlen, &j); 1220 if (error && error != ENOMEM) 1221 return (error); 1222 if (uap->oldlenp) { 1223 i = copyout(&j, uap->oldlenp, sizeof(j)); 1224 if (i) 1225 return (i); 1226 } 1227 return (error); 1228 } 1229 1230 /* 1231 * This is used from various compatibility syscalls too. That's why name 1232 * must be in kernel space. 1233 */ 1234 int 1235 userland_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval) 1236 { 1237 int error = 0; 1238 struct sysctl_req req, req2; 1239 1240 bzero(&req, sizeof req); 1241 1242 if (oldlenp) { 1243 if (inkernel) { 1244 req.oldlen = *oldlenp; 1245 } else { 1246 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 1247 if (error) 1248 return (error); 1249 } 1250 } 1251 1252 if (old) { 1253 if (!useracc(old, req.oldlen, VM_PROT_WRITE)) 1254 return (EFAULT); 1255 req.oldptr= old; 1256 } 1257 1258 if (new != NULL) { 1259 if (!useracc(new, newlen, VM_PROT_READ)) 1260 return (EFAULT); 1261 req.newlen = newlen; 1262 req.newptr = new; 1263 } 1264 1265 req.oldfunc = sysctl_old_user; 1266 req.newfunc = sysctl_new_user; 1267 #if 0 1268 req.lock = 1; 1269 #endif 1270 req.td = curthread; 1271 1272 sysctl_lock(LK_SHARED); 1273 1274 do { 1275 req2 = req; 1276 error = sysctl_root(0, name, namelen, &req2); 1277 } while (error == EAGAIN); 1278 1279 req = req2; 1280 #if 0 1281 if (req.lock == 2) 1282 vsunlock(req.oldptr, req.oldlen); 1283 #endif 1284 1285 sysctl_unlock(); 1286 1287 if (error && error != ENOMEM) 1288 return (error); 1289 1290 if (retval) { 1291 if (req.oldptr && req.oldidx > req.oldlen) 1292 *retval = req.oldlen; 1293 else 1294 *retval = req.oldidx; 1295 } 1296 return (error); 1297 } 1298 1299 static void 1300 sysctl_lock(int flag) 1301 { 1302 lockmgr(&sysctl_lkp, flag); 1303 } 1304 1305 static void 1306 sysctl_unlock(void) 1307 { 1308 lockmgr(&sysctl_lkp, LK_RELEASE); 1309 } 1310 1311 static void 1312 sysctl_ctx_lock(int flag) 1313 { 1314 lockmgr(&sysctl_ctx_lkp, flag); 1315 } 1316 1317 static void 1318 sysctl_ctx_unlock(void) 1319 { 1320 lockmgr(&sysctl_ctx_lkp, LK_RELEASE); 1321 } 1322 1323 int 1324 sysctl_int_range(SYSCTL_HANDLER_ARGS, int low, int high) 1325 { 1326 int error, value; 1327 1328 value = *(int *)arg1; 1329 error = sysctl_handle_int(oidp, &value, 0, req); 1330 if (error || !req->newptr) 1331 return (error); 1332 if (value < low || value > high) 1333 return (EINVAL); 1334 *(int *)arg1 = value; 1335 return (0); 1336 } 1337