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. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#)kern_sysctl.c 8.4 (Berkeley) 4/14/94 40 * $FreeBSD: src/sys/kern/kern_sysctl.c,v 1.92.2.9 2003/05/01 22:48:09 trhodes Exp $ 41 * $DragonFly: src/sys/kern/kern_sysctl.c,v 1.28 2007/09/03 17:32:32 dillon Exp $ 42 */ 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/buf.h> 48 #include <sys/sysctl.h> 49 #include <sys/malloc.h> 50 #include <sys/proc.h> 51 #include <sys/sysproto.h> 52 #include <sys/lock.h> 53 #include <vm/vm.h> 54 #include <vm/vm_extern.h> 55 56 static MALLOC_DEFINE(M_SYSCTL, "sysctl", "sysctl internal magic"); 57 static MALLOC_DEFINE(M_SYSCTLOID, "sysctloid", "sysctl dynamic oids"); 58 59 static struct lock sysctl_lkp; 60 static struct lock sysctl_ctx_lkp; 61 62 static void sysctl_lock(int type); 63 static void sysctl_unlock(void); 64 static void sysctl_ctx_lock(int type); 65 static void sysctl_ctx_unlock(void); 66 67 static int sysctl_root(SYSCTL_HANDLER_ARGS); 68 static void sysctl_register_oid_int(struct sysctl_oid *oipd); 69 static void sysctl_unregister_oid_int(struct sysctl_oid *oipd); 70 static struct sysctl_ctx_entry* sysctl_ctx_entry_find_int 71 (struct sysctl_ctx_list *, struct sysctl_oid *oidp); 72 73 struct sysctl_oid_list sysctl__children; /* root list */ 74 75 static struct sysctl_oid * 76 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list, int lock) 77 { 78 struct sysctl_oid *oidp; 79 80 SLIST_FOREACH(oidp, list, oid_link) { 81 if (strcmp(oidp->oid_name, name) == 0) { 82 break; 83 } 84 } 85 return (oidp); 86 } 87 88 /* 89 * Initialization of the MIB tree. 90 * 91 * Order by number in each list. 92 */ 93 94 void 95 sysctl_register_oid(struct sysctl_oid *oidp) 96 { 97 sysctl_lock(LK_EXCLUSIVE); 98 sysctl_register_oid_int(oidp); 99 sysctl_unlock(); 100 } 101 102 static void 103 sysctl_register_oid_int(struct sysctl_oid *oidp) 104 { 105 struct sysctl_oid_list *parent = oidp->oid_parent; 106 struct sysctl_oid *p; 107 struct sysctl_oid *q; 108 109 /* 110 * First check if another oid with the same name already 111 * exists in the parent's list. 112 */ 113 p = sysctl_find_oidname(oidp->oid_name, parent, 0); 114 if (p != NULL) { 115 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) 116 p->oid_refcnt++; 117 else 118 kprintf("can't re-use a leaf (%s)!\n", p->oid_name); 119 return; 120 } 121 122 /* 123 * If this oid has a number OID_AUTO, give it a number which 124 * is greater than any current oid. Make sure it is at least 125 * 256 to leave space for pre-assigned oid numbers. 126 */ 127 if (oidp->oid_number == OID_AUTO) { 128 int newoid = 0x100; /* minimum AUTO oid */ 129 130 /* 131 * Adjust based on highest oid in parent list 132 */ 133 SLIST_FOREACH(p, parent, oid_link) { 134 if (newoid <= p->oid_number) 135 newoid = p->oid_number + 1; 136 } 137 oidp->oid_number = newoid; 138 } 139 140 /* 141 * Insert the oid into the parent's list in order. 142 */ 143 q = NULL; 144 SLIST_FOREACH(p, parent, oid_link) { 145 if (oidp->oid_number < p->oid_number) 146 break; 147 q = p; 148 } 149 if (q) 150 SLIST_INSERT_AFTER(q, oidp, oid_link); 151 else 152 SLIST_INSERT_HEAD(parent, oidp, oid_link); 153 } 154 155 void 156 sysctl_unregister_oid(struct sysctl_oid *oidp) 157 { 158 sysctl_lock(LK_EXCLUSIVE); 159 sysctl_unregister_oid_int(oidp); 160 sysctl_unlock(); 161 } 162 163 static void 164 sysctl_unregister_oid_int(struct sysctl_oid *oidp) 165 { 166 struct sysctl_oid *p; 167 168 if (oidp->oid_number == OID_AUTO) 169 panic("Trying to unregister OID_AUTO entry: %p", oidp); 170 171 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 172 if (p != oidp) 173 continue; 174 SLIST_REMOVE(oidp->oid_parent, oidp, sysctl_oid, oid_link); 175 return; 176 } 177 178 /* 179 * This can happen when a module fails to register and is 180 * being unloaded afterwards. It should not be a panic() 181 * for normal use. 182 */ 183 kprintf("%s: failed to unregister sysctl\n", __func__); 184 } 185 186 /* Initialize a new context to keep track of dynamically added sysctls. */ 187 int 188 sysctl_ctx_init(struct sysctl_ctx_list *c) 189 { 190 if (c == NULL) 191 return(EINVAL); 192 TAILQ_INIT(c); 193 return(0); 194 } 195 196 /* Free the context, and destroy all dynamic oids registered in this context */ 197 int 198 sysctl_ctx_free(struct sysctl_ctx_list *clist) 199 { 200 struct sysctl_ctx_entry *e, *e1; 201 int error; 202 203 error = 0; 204 sysctl_ctx_lock(LK_EXCLUSIVE); 205 /* 206 * First perform a "dry run" to check if it's ok to remove oids. 207 * XXX FIXME 208 * XXX This algorithm is a hack. But I don't know any 209 * XXX better solution for now... 210 */ 211 TAILQ_FOREACH(e, clist, link) { 212 error = sysctl_remove_oid(e->entry, 0, 0); 213 if (error) 214 break; 215 } 216 /* 217 * Restore deregistered entries, either from the end, 218 * or from the place where error occured. 219 * e contains the entry that was not unregistered 220 */ 221 if (error) 222 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 223 else 224 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 225 while (e1 != NULL) { 226 sysctl_register_oid(e1->entry); 227 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 228 } 229 if (error) { 230 sysctl_ctx_unlock(); 231 return(EBUSY); 232 } 233 /* Now really delete the entries */ 234 e = TAILQ_FIRST(clist); 235 while (e != NULL) { 236 e1 = TAILQ_NEXT(e, link); 237 error = sysctl_remove_oid(e->entry, 1, 0); 238 if (error) 239 panic("sysctl_remove_oid: corrupt tree, entry: %s", 240 e->entry->oid_name); 241 kfree(e, M_SYSCTLOID); 242 e = e1; 243 } 244 sysctl_ctx_unlock(); 245 return (error); 246 } 247 248 /* Add an entry to the context */ 249 struct sysctl_ctx_entry * 250 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 251 { 252 struct sysctl_ctx_entry *e; 253 254 if (clist == NULL || oidp == NULL) 255 return(NULL); 256 e = kmalloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 257 e->entry = oidp; 258 sysctl_ctx_lock(LK_EXCLUSIVE); 259 TAILQ_INSERT_HEAD(clist, e, link); 260 sysctl_ctx_unlock(); 261 return (e); 262 } 263 264 /* Find an entry in the context */ 265 struct sysctl_ctx_entry * 266 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 267 { 268 struct sysctl_ctx_entry *e; 269 270 if (clist == NULL || oidp == NULL) 271 return(NULL); 272 273 sysctl_ctx_lock(LK_SHARED); 274 e = sysctl_ctx_entry_find_int(clist, oidp); 275 sysctl_ctx_unlock(); 276 277 return(e); 278 } 279 280 struct sysctl_ctx_entry * 281 sysctl_ctx_entry_find_int(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 282 { 283 struct sysctl_ctx_entry *e; 284 285 KKASSERT(clist != NULL && oidp != NULL); 286 287 for (e = TAILQ_FIRST(clist); e != NULL; e = TAILQ_NEXT(e, link)) { 288 if(e->entry == oidp) 289 break; 290 } 291 292 return (e); 293 } 294 295 /* 296 * Delete an entry from the context. 297 * NOTE: this function doesn't free oidp! You have to remove it 298 * with sysctl_remove_oid(). 299 */ 300 int 301 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 302 { 303 struct sysctl_ctx_entry *e; 304 305 if (clist == NULL || oidp == NULL) 306 return (EINVAL); 307 308 sysctl_ctx_lock(LK_EXCLUSIVE); 309 e = sysctl_ctx_entry_find_int(clist, oidp); 310 if (e == NULL) { 311 sysctl_ctx_unlock(); 312 return (ENOENT); 313 } 314 TAILQ_REMOVE(clist, e, link); 315 kfree(e, M_SYSCTLOID); 316 sysctl_ctx_unlock(); 317 318 return(0); 319 } 320 321 /* 322 * Remove dynamically created sysctl trees. 323 * oidp - top of the tree to be removed 324 * del - if 0 - just deregister, otherwise free up entries as well 325 * recurse - if != 0 traverse the subtree to be deleted 326 */ 327 int 328 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 329 { 330 struct sysctl_oid *p; 331 int error; 332 333 if (oidp == NULL) 334 return(EINVAL); 335 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 336 kprintf("can't remove non-dynamic nodes!\n"); 337 return (EINVAL); 338 } 339 sysctl_lock(LK_EXCLUSIVE | LK_CANRECURSE); 340 /* 341 * WARNING: normal method to do this should be through 342 * sysctl_ctx_free(). Use recursing as the last resort 343 * method to purge your sysctl tree of leftovers... 344 * However, if some other code still references these nodes, 345 * it will panic. 346 */ 347 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 348 if (oidp->oid_refcnt == 1) { 349 SLIST_FOREACH(p, SYSCTL_CHILDREN(oidp), oid_link) { 350 if (!recurse) { 351 sysctl_unlock(); 352 return(ENOTEMPTY); 353 } 354 error = sysctl_remove_oid(p, del, recurse); 355 if (error) { 356 sysctl_unlock(); 357 return(error); 358 } 359 } 360 if (del) 361 kfree(SYSCTL_CHILDREN(oidp), M_SYSCTLOID); 362 } 363 } 364 if (oidp->oid_refcnt > 1 ) { 365 oidp->oid_refcnt--; 366 } else { 367 if (oidp->oid_refcnt == 0) { 368 kprintf("Warning: bad oid_refcnt=%u (%s)!\n", 369 oidp->oid_refcnt, oidp->oid_name); 370 sysctl_unlock(); 371 return(EINVAL); 372 } 373 sysctl_unregister_oid_int(oidp); 374 if (del) { 375 if (oidp->oid_descr) 376 kfree(__DECONST(char *,oidp->oid_descr), 377 M_SYSCTLOID); 378 kfree(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); 379 kfree(oidp, M_SYSCTLOID); 380 } 381 } 382 sysctl_unlock(); 383 return(0); 384 } 385 386 /* 387 * Create new sysctls at run time. 388 * clist may point to a valid context initialized with sysctl_ctx_init(). 389 */ 390 struct sysctl_oid * 391 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 392 int number, const char *name, int kind, void *arg1, int arg2, 393 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr) 394 { 395 struct sysctl_oid *oidp; 396 ssize_t len; 397 char *newname; 398 399 /* You have to hook up somewhere.. */ 400 if (parent == NULL) 401 return(NULL); 402 sysctl_lock(LK_EXCLUSIVE); 403 /* Check if the node already exists, otherwise create it */ 404 oidp = sysctl_find_oidname(name, parent, 0); 405 if (oidp != NULL) { 406 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 407 oidp->oid_refcnt++; 408 /* Update the context */ 409 if (clist != NULL) 410 sysctl_ctx_entry_add(clist, oidp); 411 sysctl_unlock(); 412 return (oidp); 413 } else { 414 kprintf("can't re-use a leaf (%s)!\n", name); 415 sysctl_unlock(); 416 return (NULL); 417 } 418 } 419 oidp = kmalloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK | M_ZERO); 420 oidp->oid_parent = parent; 421 SLIST_NEXT(oidp, oid_link) = NULL; 422 oidp->oid_number = number; 423 oidp->oid_refcnt = 1; 424 len = strlen(name); 425 newname = kmalloc(len + 1, M_SYSCTLOID, M_WAITOK); 426 bcopy(name, newname, len + 1); 427 newname[len] = '\0'; 428 oidp->oid_name = newname; 429 oidp->oid_handler = handler; 430 oidp->oid_kind = CTLFLAG_DYN | kind; 431 if ((kind & CTLTYPE) == CTLTYPE_NODE) { 432 struct sysctl_oid_list *children; 433 434 /* Allocate space for children */ 435 children = kmalloc(sizeof(*children), M_SYSCTLOID, M_WAITOK); 436 SYSCTL_SET_CHILDREN(oidp, children); 437 SLIST_INIT(children); 438 } else { 439 oidp->oid_arg1 = arg1; 440 oidp->oid_arg2 = arg2; 441 } 442 oidp->oid_fmt = fmt; 443 if (descr) { 444 int len = strlen(descr) + 1; 445 oidp->oid_descr = kmalloc(len, M_SYSCTLOID, M_WAITOK); 446 if (oidp->oid_descr) 447 strcpy((char *)(uintptr_t)(const void *)oidp->oid_descr, descr); 448 }; 449 /* Update the context, if used */ 450 if (clist != NULL) 451 sysctl_ctx_entry_add(clist, oidp); 452 /* Register this oid */ 453 sysctl_register_oid_int(oidp); 454 sysctl_unlock(); 455 return (oidp); 456 } 457 458 /* 459 * Register the kernel's oids on startup. 460 */ 461 SET_DECLARE(sysctl_set, struct sysctl_oid); 462 463 static void 464 sysctl_register_all(void *arg) 465 { 466 struct sysctl_oid **oidp; 467 468 lockinit(&sysctl_lkp, "sysctl", 0, 0); 469 lockinit(&sysctl_ctx_lkp, "sysctl ctx", 0, 0); 470 SET_FOREACH(oidp, sysctl_set) 471 sysctl_register_oid_int(*oidp); 472 } 473 474 SYSINIT(sysctl, SI_BOOT1_POST, SI_ORDER_ANY, sysctl_register_all, 0); 475 476 /* 477 * "Staff-functions" 478 * 479 * These functions implement a presently undocumented interface 480 * used by the sysctl program to walk the tree, and get the type 481 * so it can print the value. 482 * This interface is under work and consideration, and should probably 483 * be killed with a big axe by the first person who can find the time. 484 * (be aware though, that the proper interface isn't as obvious as it 485 * may seem, there are various conflicting requirements. 486 * 487 * {0,0} kprintf the entire MIB-tree. 488 * {0,1,...} return the name of the "..." OID. 489 * {0,2,...} return the next OID. 490 * {0,3} return the OID of the name in "new" 491 * {0,4,...} return the kind & format info for the "..." OID. 492 */ 493 494 static void 495 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 496 { 497 int k; 498 struct sysctl_oid *oidp; 499 500 sysctl_lock(LK_SHARED); 501 SLIST_FOREACH(oidp, l, oid_link) { 502 503 for (k=0; k<i; k++) 504 kprintf(" "); 505 506 kprintf("%d %s ", oidp->oid_number, oidp->oid_name); 507 508 kprintf("%c%c", 509 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 510 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 511 512 if (oidp->oid_handler) 513 kprintf(" *Handler"); 514 515 switch (oidp->oid_kind & CTLTYPE) { 516 case CTLTYPE_NODE: 517 kprintf(" Node\n"); 518 if (!oidp->oid_handler) { 519 sysctl_sysctl_debug_dump_node( 520 oidp->oid_arg1, i+2); 521 } 522 break; 523 case CTLTYPE_INT: kprintf(" Int\n"); break; 524 case CTLTYPE_STRING: kprintf(" String\n"); break; 525 case CTLTYPE_QUAD: kprintf(" Quad\n"); break; 526 case CTLTYPE_OPAQUE: kprintf(" Opaque/struct\n"); break; 527 default: kprintf("\n"); 528 } 529 530 } 531 sysctl_unlock(); 532 } 533 534 static int 535 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 536 { 537 int error; 538 539 error = suser(req->td); 540 if (error) 541 return error; 542 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 543 return ENOENT; 544 } 545 546 SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD, 547 0, 0, sysctl_sysctl_debug, "-", ""); 548 549 static int 550 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 551 { 552 int *name = (int *) arg1; 553 u_int namelen = arg2; 554 int error = 0; 555 struct sysctl_oid *oid; 556 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 557 char buf[10]; 558 559 sysctl_lock(LK_SHARED); 560 while (namelen) { 561 if (!lsp) { 562 ksnprintf(buf,sizeof(buf),"%d",*name); 563 if (req->oldidx) 564 error = SYSCTL_OUT(req, ".", 1); 565 if (!error) 566 error = SYSCTL_OUT(req, buf, strlen(buf)); 567 if (error) { 568 sysctl_unlock(); 569 return (error); 570 } 571 namelen--; 572 name++; 573 continue; 574 } 575 lsp2 = 0; 576 SLIST_FOREACH(oid, lsp, oid_link) { 577 if (oid->oid_number != *name) 578 continue; 579 580 if (req->oldidx) 581 error = SYSCTL_OUT(req, ".", 1); 582 if (!error) 583 error = SYSCTL_OUT(req, oid->oid_name, 584 strlen(oid->oid_name)); 585 if (error) { 586 sysctl_unlock(); 587 return (error); 588 } 589 590 namelen--; 591 name++; 592 593 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 594 break; 595 596 if (oid->oid_handler) 597 break; 598 599 lsp2 = (struct sysctl_oid_list *)oid->oid_arg1; 600 break; 601 } 602 lsp = lsp2; 603 } 604 sysctl_unlock(); 605 return (SYSCTL_OUT(req, "", 1)); 606 } 607 608 SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD, sysctl_sysctl_name, ""); 609 610 static int 611 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 612 int *next, int *len, int level, struct sysctl_oid **oidpp) 613 { 614 struct sysctl_oid *oidp; 615 616 *len = level; 617 sysctl_lock(LK_SHARED); 618 SLIST_FOREACH(oidp, lsp, oid_link) { 619 *next = oidp->oid_number; 620 *oidpp = oidp; 621 622 if (!namelen) { 623 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) { 624 sysctl_unlock(); 625 return 0; 626 } 627 if (oidp->oid_handler) { 628 /* We really should call the handler here...*/ 629 sysctl_unlock(); 630 return 0; 631 } 632 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 633 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 634 len, level+1, oidpp)) { 635 sysctl_unlock(); 636 return 0; 637 } 638 goto emptynode; 639 } 640 641 if (oidp->oid_number < *name) 642 continue; 643 644 if (oidp->oid_number > *name) { 645 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) { 646 sysctl_unlock(); 647 return 0; 648 } 649 if (oidp->oid_handler) { 650 sysctl_unlock(); 651 return 0; 652 } 653 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 654 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 655 next+1, len, level+1, oidpp)) { 656 sysctl_unlock(); 657 return (0); 658 } 659 goto next; 660 } 661 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 662 continue; 663 664 if (oidp->oid_handler) 665 continue; 666 667 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 668 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 669 len, level+1, oidpp)) { 670 sysctl_unlock(); 671 return (0); 672 } 673 next: 674 namelen = 1; 675 *len = level; 676 emptynode: 677 *len = level; 678 } 679 sysctl_unlock(); 680 return 1; 681 } 682 683 static int 684 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 685 { 686 int *name = (int *) arg1; 687 u_int namelen = arg2; 688 int i, j, error; 689 struct sysctl_oid *oid; 690 struct sysctl_oid_list *lsp = &sysctl__children; 691 int newoid[CTL_MAXNAME]; 692 693 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 694 if (i) 695 return ENOENT; 696 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 697 return (error); 698 } 699 700 SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD, sysctl_sysctl_next, ""); 701 702 static int 703 name2oid (char *name, int *oid, int *len, struct sysctl_oid **oidpp) 704 { 705 int i; 706 struct sysctl_oid *oidp; 707 struct sysctl_oid_list *lsp = &sysctl__children; 708 char *p; 709 710 if (!*name) 711 return ENOENT; 712 713 p = name + strlen(name) - 1 ; 714 if (*p == '.') 715 *p = '\0'; 716 717 *len = 0; 718 719 for (p = name; *p && *p != '.'; p++) 720 ; 721 i = *p; 722 if (i == '.') 723 *p = '\0'; 724 725 sysctl_lock(LK_SHARED); 726 oidp = SLIST_FIRST(lsp); 727 728 while (oidp && *len < CTL_MAXNAME) { 729 if (strcmp(name, oidp->oid_name)) { 730 oidp = SLIST_NEXT(oidp, oid_link); 731 continue; 732 } 733 *oid++ = oidp->oid_number; 734 (*len)++; 735 736 if (!i) { 737 if (oidpp) 738 *oidpp = oidp; 739 sysctl_unlock(); 740 return (0); 741 } 742 743 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 744 break; 745 746 if (oidp->oid_handler) 747 break; 748 749 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 750 oidp = SLIST_FIRST(lsp); 751 name = p+1; 752 for (p = name; *p && *p != '.'; p++) 753 ; 754 i = *p; 755 if (i == '.') 756 *p = '\0'; 757 } 758 sysctl_unlock(); 759 return ENOENT; 760 } 761 762 static int 763 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 764 { 765 char *p; 766 int error, oid[CTL_MAXNAME], len; 767 struct sysctl_oid *op = 0; 768 769 if (!req->newlen) 770 return ENOENT; 771 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 772 return (ENAMETOOLONG); 773 774 p = kmalloc(req->newlen+1, M_SYSCTL, M_WAITOK); 775 776 error = SYSCTL_IN(req, p, req->newlen); 777 if (error) { 778 kfree(p, M_SYSCTL); 779 return (error); 780 } 781 782 p [req->newlen] = '\0'; 783 784 error = name2oid(p, oid, &len, &op); 785 786 kfree(p, M_SYSCTL); 787 788 if (error) 789 return (error); 790 791 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 792 return (error); 793 } 794 795 SYSCTL_PROC(_sysctl, 3, name2oid, CTLFLAG_RW|CTLFLAG_ANYBODY, 0, 0, 796 sysctl_sysctl_name2oid, "I", ""); 797 798 static int 799 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 800 { 801 struct sysctl_oid *oid; 802 int error; 803 804 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 805 if (error) 806 return (error); 807 808 if (!oid->oid_fmt) 809 return (ENOENT); 810 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 811 if (error) 812 return (error); 813 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 814 return (error); 815 } 816 817 818 SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD, sysctl_sysctl_oidfmt, ""); 819 820 static int 821 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 822 { 823 struct sysctl_oid *oid; 824 int error; 825 826 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 827 if (error) 828 return (error); 829 830 if (!oid->oid_descr) 831 return (ENOENT); 832 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 833 return (error); 834 } 835 836 SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD, sysctl_sysctl_oiddescr, ""); 837 838 /* 839 * Default "handler" functions. 840 */ 841 842 /* 843 * Handle an int, signed or unsigned. 844 * Two cases: 845 * a variable: point arg1 at it. 846 * a constant: pass it in arg2. 847 */ 848 849 int 850 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 851 { 852 int error = 0; 853 854 if (arg1) 855 error = SYSCTL_OUT(req, arg1, sizeof(int)); 856 else 857 error = SYSCTL_OUT(req, &arg2, sizeof(int)); 858 859 if (error || !req->newptr) 860 return (error); 861 862 if (!arg1) 863 error = EPERM; 864 else 865 error = SYSCTL_IN(req, arg1, sizeof(int)); 866 return (error); 867 } 868 869 /* 870 * Handle a long, signed or unsigned. arg1 points to it. 871 */ 872 873 int 874 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 875 { 876 int error = 0; 877 878 if (!arg1) 879 return (EINVAL); 880 error = SYSCTL_OUT(req, arg1, sizeof(long)); 881 882 if (error || !req->newptr) 883 return (error); 884 885 error = SYSCTL_IN(req, arg1, sizeof(long)); 886 return (error); 887 } 888 889 /* 890 * Handle a quad, signed or unsigned. arg1 points to it. 891 */ 892 893 int 894 sysctl_handle_quad(SYSCTL_HANDLER_ARGS) 895 { 896 int error = 0; 897 898 if (!arg1) 899 return (EINVAL); 900 error = SYSCTL_OUT(req, arg1, sizeof(quad_t)); 901 902 if (error || !req->newptr) 903 return (error); 904 905 error = SYSCTL_IN(req, arg1, sizeof(quad_t)); 906 return (error); 907 } 908 909 /* 910 * Handle our generic '\0' terminated 'C' string. 911 * Two cases: 912 * a variable string: point arg1 at it, arg2 is max length. 913 * a constant string: point arg1 at it, arg2 is zero. 914 */ 915 916 int 917 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 918 { 919 int error=0; 920 921 error = SYSCTL_OUT(req, arg1, strlen((char *)arg1)+1); 922 923 if (error || !req->newptr) 924 return (error); 925 926 if ((req->newlen - req->newidx) >= arg2) { 927 error = EINVAL; 928 } else { 929 arg2 = (req->newlen - req->newidx); 930 error = SYSCTL_IN(req, arg1, arg2); 931 ((char *)arg1)[arg2] = '\0'; 932 } 933 934 return (error); 935 } 936 937 /* 938 * Handle any kind of opaque data. 939 * arg1 points to it, arg2 is the size. 940 */ 941 942 int 943 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 944 { 945 int error; 946 947 error = SYSCTL_OUT(req, arg1, arg2); 948 949 if (error || !req->newptr) 950 return (error); 951 952 error = SYSCTL_IN(req, arg1, arg2); 953 954 return (error); 955 } 956 957 /* 958 * Transfer functions to/from kernel space. 959 * XXX: rather untested at this point 960 */ 961 static int 962 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 963 { 964 size_t i = 0; 965 966 if (req->oldptr) { 967 i = l; 968 if (i > req->oldlen - req->oldidx) 969 i = req->oldlen - req->oldidx; 970 if (i > 0) 971 bcopy(p, (char *)req->oldptr + req->oldidx, i); 972 } 973 req->oldidx += l; 974 if (req->oldptr && i != l) 975 return (ENOMEM); 976 return (0); 977 } 978 979 static int 980 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 981 { 982 983 if (!req->newptr) 984 return 0; 985 if (req->newlen - req->newidx < l) 986 return (EINVAL); 987 bcopy((char *)req->newptr + req->newidx, p, l); 988 req->newidx += l; 989 return (0); 990 } 991 992 int 993 kernel_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval) 994 { 995 int error = 0; 996 struct sysctl_req req; 997 998 bzero(&req, sizeof req); 999 1000 req.td = curthread; 1001 1002 if (oldlenp) { 1003 req.oldlen = *oldlenp; 1004 } 1005 1006 if (old) { 1007 req.oldptr = old; 1008 } 1009 1010 if (new != NULL) { 1011 req.newlen = newlen; 1012 req.newptr = new; 1013 } 1014 1015 req.oldfunc = sysctl_old_kernel; 1016 req.newfunc = sysctl_new_kernel; 1017 req.lock = 1; 1018 1019 sysctl_lock(LK_SHARED); 1020 1021 error = sysctl_root(0, name, namelen, &req); 1022 1023 if (req.lock == 2) 1024 vsunlock(req.oldptr, req.oldlen); 1025 1026 sysctl_unlock(); 1027 1028 if (error && error != ENOMEM) 1029 return (error); 1030 1031 if (retval) { 1032 if (req.oldptr && req.oldidx > req.oldlen) 1033 *retval = req.oldlen; 1034 else 1035 *retval = req.oldidx; 1036 } 1037 return (error); 1038 } 1039 1040 int 1041 kernel_sysctlbyname(char *name, void *old, size_t *oldlenp, 1042 void *new, size_t newlen, size_t *retval) 1043 { 1044 int oid[CTL_MAXNAME]; 1045 size_t oidlen, plen; 1046 int error; 1047 1048 oid[0] = 0; /* sysctl internal magic */ 1049 oid[1] = 3; /* name2oid */ 1050 oidlen = sizeof(oid); 1051 1052 error = kernel_sysctl(oid, 2, oid, &oidlen, (void *)name, 1053 strlen(name), &plen); 1054 if (error) 1055 return (error); 1056 1057 error = kernel_sysctl(oid, plen / sizeof(int), old, oldlenp, 1058 new, newlen, retval); 1059 return (error); 1060 } 1061 1062 /* 1063 * Transfer function to/from user space. 1064 */ 1065 static int 1066 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 1067 { 1068 int error = 0; 1069 size_t i = 0; 1070 1071 if (req->lock == 1 && req->oldptr) { 1072 vslock(req->oldptr, req->oldlen); 1073 req->lock = 2; 1074 } 1075 if (req->oldptr) { 1076 i = l; 1077 if (i > req->oldlen - req->oldidx) 1078 i = req->oldlen - req->oldidx; 1079 if (i > 0) 1080 error = copyout(p, (char *)req->oldptr + req->oldidx, 1081 i); 1082 } 1083 req->oldidx += l; 1084 if (error) 1085 return (error); 1086 if (req->oldptr && i < l) 1087 return (ENOMEM); 1088 return (0); 1089 } 1090 1091 static int 1092 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1093 { 1094 int error; 1095 1096 if (!req->newptr) 1097 return 0; 1098 if (req->newlen - req->newidx < l) 1099 return (EINVAL); 1100 error = copyin((char *)req->newptr + req->newidx, p, l); 1101 req->newidx += l; 1102 return (error); 1103 } 1104 1105 int 1106 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 1107 int *nindx, struct sysctl_req *req) 1108 { 1109 struct sysctl_oid *oid; 1110 int indx; 1111 1112 sysctl_lock(LK_SHARED); 1113 oid = SLIST_FIRST(&sysctl__children); 1114 indx = 0; 1115 while (oid && indx < CTL_MAXNAME) { 1116 if (oid->oid_number == name[indx]) { 1117 indx++; 1118 if (oid->oid_kind & CTLFLAG_NOLOCK) 1119 req->lock = 0; 1120 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1121 if (oid->oid_handler != NULL || 1122 indx == namelen) { 1123 *noid = oid; 1124 if (nindx != NULL) 1125 *nindx = indx; 1126 sysctl_unlock(); 1127 return (0); 1128 } 1129 oid = SLIST_FIRST( 1130 (struct sysctl_oid_list *)oid->oid_arg1); 1131 } else if (indx == namelen) { 1132 *noid = oid; 1133 if (nindx != NULL) 1134 *nindx = indx; 1135 sysctl_unlock(); 1136 return (0); 1137 } else { 1138 sysctl_unlock(); 1139 return (ENOTDIR); 1140 } 1141 } else { 1142 oid = SLIST_NEXT(oid, oid_link); 1143 } 1144 } 1145 sysctl_unlock(); 1146 return (ENOENT); 1147 } 1148 1149 /* 1150 * Traverse our tree, and find the right node, execute whatever it points 1151 * to, and return the resulting error code. 1152 */ 1153 1154 int 1155 sysctl_root(SYSCTL_HANDLER_ARGS) 1156 { 1157 struct thread *td = req->td; 1158 struct proc *p = td ? td->td_proc : NULL; 1159 struct sysctl_oid *oid; 1160 int error, indx; 1161 1162 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 1163 if (error) 1164 return (error); 1165 1166 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1167 /* 1168 * You can't call a sysctl when it's a node, but has 1169 * no handler. Inform the user that it's a node. 1170 * The indx may or may not be the same as namelen. 1171 */ 1172 if (oid->oid_handler == NULL) 1173 return (EISDIR); 1174 } 1175 1176 /* If writing isn't allowed */ 1177 if (req->newptr && (!(oid->oid_kind & CTLFLAG_WR) || 1178 ((oid->oid_kind & CTLFLAG_SECURE) && securelevel > 0))) 1179 return (EPERM); 1180 1181 /* Most likely only root can write */ 1182 if (!(oid->oid_kind & CTLFLAG_ANYBODY) && req->newptr && p && 1183 (error = suser_cred(p->p_ucred, 1184 (oid->oid_kind & CTLFLAG_PRISON) ? PRISON_ROOT : 0))) 1185 return (error); 1186 1187 if (!oid->oid_handler) 1188 return EINVAL; 1189 1190 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) 1191 error = oid->oid_handler(oid, (int *)arg1 + indx, arg2 - indx, 1192 req); 1193 else 1194 error = oid->oid_handler(oid, oid->oid_arg1, oid->oid_arg2, 1195 req); 1196 return (error); 1197 } 1198 1199 int 1200 sys___sysctl(struct sysctl_args *uap) 1201 { 1202 int error, i, name[CTL_MAXNAME]; 1203 size_t j; 1204 1205 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 1206 return (EINVAL); 1207 1208 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 1209 if (error) 1210 return (error); 1211 1212 error = userland_sysctl(name, uap->namelen, 1213 uap->old, uap->oldlenp, 0, 1214 uap->new, uap->newlen, &j); 1215 if (error && error != ENOMEM) 1216 return (error); 1217 if (uap->oldlenp) { 1218 i = copyout(&j, uap->oldlenp, sizeof(j)); 1219 if (i) 1220 return (i); 1221 } 1222 return (error); 1223 } 1224 1225 /* 1226 * This is used from various compatibility syscalls too. That's why name 1227 * must be in kernel space. 1228 */ 1229 int 1230 userland_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval) 1231 { 1232 int error = 0; 1233 struct sysctl_req req, req2; 1234 1235 bzero(&req, sizeof req); 1236 1237 if (oldlenp) { 1238 if (inkernel) { 1239 req.oldlen = *oldlenp; 1240 } else { 1241 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 1242 if (error) 1243 return (error); 1244 } 1245 } 1246 1247 if (old) { 1248 if (!useracc(old, req.oldlen, VM_PROT_WRITE)) 1249 return (EFAULT); 1250 req.oldptr= old; 1251 } 1252 1253 if (new != NULL) { 1254 if (!useracc(new, newlen, VM_PROT_READ)) 1255 return (EFAULT); 1256 req.newlen = newlen; 1257 req.newptr = new; 1258 } 1259 1260 req.oldfunc = sysctl_old_user; 1261 req.newfunc = sysctl_new_user; 1262 req.lock = 1; 1263 req.td = curthread; 1264 1265 sysctl_lock(LK_SHARED); 1266 1267 do { 1268 req2 = req; 1269 error = sysctl_root(0, name, namelen, &req2); 1270 } while (error == EAGAIN); 1271 1272 req = req2; 1273 if (req.lock == 2) 1274 vsunlock(req.oldptr, req.oldlen); 1275 1276 sysctl_unlock(); 1277 1278 if (error && error != ENOMEM) 1279 return (error); 1280 1281 if (retval) { 1282 if (req.oldptr && req.oldidx > req.oldlen) 1283 *retval = req.oldlen; 1284 else 1285 *retval = req.oldidx; 1286 } 1287 return (error); 1288 } 1289 1290 static void 1291 sysctl_lock(int flag) 1292 { 1293 lockmgr(&sysctl_lkp, flag); 1294 } 1295 1296 static void 1297 sysctl_unlock(void) 1298 { 1299 lockmgr(&sysctl_lkp, LK_RELEASE); 1300 } 1301 1302 static void 1303 sysctl_ctx_lock(int flag) 1304 { 1305 lockmgr(&sysctl_ctx_lkp, flag); 1306 } 1307 1308 static void 1309 sysctl_ctx_unlock(void) 1310 { 1311 lockmgr(&sysctl_ctx_lkp, LK_RELEASE); 1312 } 1313 1314