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 1.13 2003/11/14 02:54:52 daver 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 <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 /* 59 * Locking and stats 60 */ 61 static struct sysctl_lock { 62 int sl_lock; 63 int sl_want; 64 int sl_locked; 65 } memlock; 66 67 static int sysctl_root(SYSCTL_HANDLER_ARGS); 68 69 struct sysctl_oid_list sysctl__children; /* root list */ 70 71 static struct sysctl_oid * 72 sysctl_find_oidname(const char *name, struct sysctl_oid_list *list) 73 { 74 struct sysctl_oid *oidp; 75 76 SLIST_FOREACH(oidp, list, oid_link) { 77 if (strcmp(oidp->oid_name, name) == 0) { 78 return (oidp); 79 } 80 } 81 return (NULL); 82 } 83 84 /* 85 * Initialization of the MIB tree. 86 * 87 * Order by number in each list. 88 */ 89 90 void sysctl_register_oid(struct sysctl_oid *oidp) 91 { 92 struct sysctl_oid_list *parent = oidp->oid_parent; 93 struct sysctl_oid *p; 94 struct sysctl_oid *q; 95 96 /* 97 * First check if another oid with the same name already 98 * exists in the parent's list. 99 */ 100 p = sysctl_find_oidname(oidp->oid_name, parent); 101 if (p != NULL) { 102 if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 103 p->oid_refcnt++; 104 return; 105 } else { 106 printf("can't re-use a leaf (%s)!\n", p->oid_name); 107 return; 108 } 109 } 110 /* 111 * If this oid has a number OID_AUTO, give it a number which 112 * is greater than any current oid. Make sure it is at least 113 * 100 to leave space for pre-assigned oid numbers. 114 */ 115 if (oidp->oid_number == OID_AUTO) { 116 static int newoid = 100; 117 oidp->oid_number = newoid++; 118 if (newoid == 0x7fffffff) 119 panic("out of oids"); 120 } 121 122 /* 123 * Insert the oid into the parent's list in order. 124 */ 125 q = NULL; 126 SLIST_FOREACH(p, parent, oid_link) { 127 if (oidp->oid_number < p->oid_number) 128 break; 129 q = p; 130 } 131 if (q) 132 SLIST_INSERT_AFTER(q, oidp, oid_link); 133 else 134 SLIST_INSERT_HEAD(parent, oidp, oid_link); 135 } 136 137 void sysctl_unregister_oid(struct sysctl_oid *oidp) 138 { 139 struct sysctl_oid *p; 140 int error; 141 142 error = ENOENT; 143 if (oidp->oid_number == OID_AUTO) { 144 error = EINVAL; 145 } else { 146 SLIST_FOREACH(p, oidp->oid_parent, oid_link) { 147 if (p == oidp) { 148 SLIST_REMOVE(oidp->oid_parent, oidp, 149 sysctl_oid, oid_link); 150 error = 0; 151 break; 152 } 153 } 154 } 155 156 /* 157 * This can happen when a module fails to register and is 158 * being unloaded afterwards. It should not be a panic() 159 * for normal use. 160 */ 161 if (error) 162 printf("%s: failed to unregister sysctl\n", __func__); 163 } 164 165 /* Initialize a new context to keep track of dynamically added sysctls. */ 166 int 167 sysctl_ctx_init(struct sysctl_ctx_list *c) 168 { 169 170 if (c == NULL) { 171 return (EINVAL); 172 } 173 TAILQ_INIT(c); 174 return (0); 175 } 176 177 /* Free the context, and destroy all dynamic oids registered in this context */ 178 int 179 sysctl_ctx_free(struct sysctl_ctx_list *clist) 180 { 181 struct sysctl_ctx_entry *e, *e1; 182 int error; 183 184 error = 0; 185 /* 186 * First perform a "dry run" to check if it's ok to remove oids. 187 * XXX FIXME 188 * XXX This algorithm is a hack. But I don't know any 189 * XXX better solution for now... 190 */ 191 TAILQ_FOREACH(e, clist, link) { 192 error = sysctl_remove_oid(e->entry, 0, 0); 193 if (error) 194 break; 195 } 196 /* 197 * Restore deregistered entries, either from the end, 198 * or from the place where error occured. 199 * e contains the entry that was not unregistered 200 */ 201 if (error) 202 e1 = TAILQ_PREV(e, sysctl_ctx_list, link); 203 else 204 e1 = TAILQ_LAST(clist, sysctl_ctx_list); 205 while (e1 != NULL) { 206 sysctl_register_oid(e1->entry); 207 e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); 208 } 209 if (error) 210 return(EBUSY); 211 /* Now really delete the entries */ 212 e = TAILQ_FIRST(clist); 213 while (e != NULL) { 214 e1 = TAILQ_NEXT(e, link); 215 error = sysctl_remove_oid(e->entry, 1, 0); 216 if (error) 217 panic("sysctl_remove_oid: corrupt tree, entry: %s", 218 e->entry->oid_name); 219 free(e, M_SYSCTLOID); 220 e = e1; 221 } 222 return (error); 223 } 224 225 /* Add an entry to the context */ 226 struct sysctl_ctx_entry * 227 sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 228 { 229 struct sysctl_ctx_entry *e; 230 231 if (clist == NULL || oidp == NULL) 232 return(NULL); 233 e = malloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); 234 e->entry = oidp; 235 TAILQ_INSERT_HEAD(clist, e, link); 236 return (e); 237 } 238 239 /* Find an entry in the context */ 240 struct sysctl_ctx_entry * 241 sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 242 { 243 struct sysctl_ctx_entry *e; 244 245 if (clist == NULL || oidp == NULL) 246 return(NULL); 247 for (e = TAILQ_FIRST(clist); e != NULL; e = TAILQ_NEXT(e, link)) { 248 if(e->entry == oidp) 249 return(e); 250 } 251 return (e); 252 } 253 254 /* 255 * Delete an entry from the context. 256 * NOTE: this function doesn't free oidp! You have to remove it 257 * with sysctl_remove_oid(). 258 */ 259 int 260 sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) 261 { 262 struct sysctl_ctx_entry *e; 263 264 if (clist == NULL || oidp == NULL) 265 return (EINVAL); 266 e = sysctl_ctx_entry_find(clist, oidp); 267 if (e != NULL) { 268 TAILQ_REMOVE(clist, e, link); 269 free(e, M_SYSCTLOID); 270 return (0); 271 } else 272 return (ENOENT); 273 } 274 275 /* 276 * Remove dynamically created sysctl trees. 277 * oidp - top of the tree to be removed 278 * del - if 0 - just deregister, otherwise free up entries as well 279 * recurse - if != 0 traverse the subtree to be deleted 280 */ 281 int 282 sysctl_remove_oid(struct sysctl_oid *oidp, int del, int recurse) 283 { 284 struct sysctl_oid *p; 285 int error; 286 287 if (oidp == NULL) 288 return(EINVAL); 289 if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { 290 printf("can't remove non-dynamic nodes!\n"); 291 return (EINVAL); 292 } 293 /* 294 * WARNING: normal method to do this should be through 295 * sysctl_ctx_free(). Use recursing as the last resort 296 * method to purge your sysctl tree of leftovers... 297 * However, if some other code still references these nodes, 298 * it will panic. 299 */ 300 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 301 if (oidp->oid_refcnt == 1) { 302 SLIST_FOREACH(p, SYSCTL_CHILDREN(oidp), oid_link) { 303 if (!recurse) 304 return (ENOTEMPTY); 305 error = sysctl_remove_oid(p, del, recurse); 306 if (error) 307 return (error); 308 } 309 if (del) 310 free(SYSCTL_CHILDREN(oidp), M_SYSCTLOID); 311 } 312 } 313 if (oidp->oid_refcnt > 1 ) { 314 oidp->oid_refcnt--; 315 } else { 316 if (oidp->oid_refcnt == 0) { 317 printf("Warning: bad oid_refcnt=%u (%s)!\n", 318 oidp->oid_refcnt, oidp->oid_name); 319 return (EINVAL); 320 } 321 sysctl_unregister_oid(oidp); 322 if (del) { 323 if (oidp->oid_descr) 324 free((void *)(uintptr_t)(const void *)oidp->oid_descr, M_SYSCTLOID); 325 free((void *)(uintptr_t)(const void *)oidp->oid_name, 326 M_SYSCTLOID); 327 free(oidp, M_SYSCTLOID); 328 } 329 } 330 return (0); 331 } 332 333 /* 334 * Create new sysctls at run time. 335 * clist may point to a valid context initialized with sysctl_ctx_init(). 336 */ 337 struct sysctl_oid * 338 sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, 339 int number, const char *name, int kind, void *arg1, int arg2, 340 int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr) 341 { 342 struct sysctl_oid *oidp; 343 ssize_t len; 344 char *newname; 345 346 /* You have to hook up somewhere.. */ 347 if (parent == NULL) 348 return(NULL); 349 /* Check if the node already exists, otherwise create it */ 350 oidp = sysctl_find_oidname(name, parent); 351 if (oidp != NULL) { 352 if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 353 oidp->oid_refcnt++; 354 /* Update the context */ 355 if (clist != NULL) 356 sysctl_ctx_entry_add(clist, oidp); 357 return (oidp); 358 } else { 359 printf("can't re-use a leaf (%s)!\n", name); 360 return (NULL); 361 } 362 } 363 oidp = malloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK); 364 bzero(oidp, sizeof(struct sysctl_oid)); 365 oidp->oid_parent = parent; 366 SLIST_NEXT(oidp, oid_link) = NULL; 367 oidp->oid_number = number; 368 oidp->oid_refcnt = 1; 369 len = strlen(name); 370 newname = malloc(len + 1, M_SYSCTLOID, M_WAITOK); 371 bcopy(name, newname, len + 1); 372 newname[len] = '\0'; 373 oidp->oid_name = newname; 374 oidp->oid_handler = handler; 375 oidp->oid_kind = CTLFLAG_DYN | kind; 376 if ((kind & CTLTYPE) == CTLTYPE_NODE) { 377 /* Allocate space for children */ 378 SYSCTL_CHILDREN(oidp) = malloc(sizeof(struct sysctl_oid_list), 379 M_SYSCTLOID, M_WAITOK); 380 SLIST_INIT(SYSCTL_CHILDREN(oidp)); 381 } else { 382 oidp->oid_arg1 = arg1; 383 oidp->oid_arg2 = arg2; 384 } 385 oidp->oid_fmt = fmt; 386 if (descr) { 387 int len = strlen(descr) + 1; 388 oidp->oid_descr = malloc(len, M_SYSCTLOID, M_WAITOK); 389 if (oidp->oid_descr) 390 strcpy((char *)(uintptr_t)(const void *)oidp->oid_descr, descr); 391 }; 392 /* Update the context, if used */ 393 if (clist != NULL) 394 sysctl_ctx_entry_add(clist, oidp); 395 /* Register this oid */ 396 sysctl_register_oid(oidp); 397 return (oidp); 398 } 399 400 /* 401 * Register the kernel's oids on startup. 402 */ 403 SET_DECLARE(sysctl_set, struct sysctl_oid); 404 405 static void sysctl_register_all(void *arg) 406 { 407 struct sysctl_oid **oidp; 408 409 SET_FOREACH(oidp, sysctl_set) 410 sysctl_register_oid(*oidp); 411 } 412 413 SYSINIT(sysctl, SI_SUB_KMEM, SI_ORDER_ANY, sysctl_register_all, 0); 414 415 /* 416 * "Staff-functions" 417 * 418 * These functions implement a presently undocumented interface 419 * used by the sysctl program to walk the tree, and get the type 420 * so it can print the value. 421 * This interface is under work and consideration, and should probably 422 * be killed with a big axe by the first person who can find the time. 423 * (be aware though, that the proper interface isn't as obvious as it 424 * may seem, there are various conflicting requirements. 425 * 426 * {0,0} printf the entire MIB-tree. 427 * {0,1,...} return the name of the "..." OID. 428 * {0,2,...} return the next OID. 429 * {0,3} return the OID of the name in "new" 430 * {0,4,...} return the kind & format info for the "..." OID. 431 */ 432 433 static void 434 sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) 435 { 436 int k; 437 struct sysctl_oid *oidp; 438 439 SLIST_FOREACH(oidp, l, oid_link) { 440 441 for (k=0; k<i; k++) 442 printf(" "); 443 444 printf("%d %s ", oidp->oid_number, oidp->oid_name); 445 446 printf("%c%c", 447 oidp->oid_kind & CTLFLAG_RD ? 'R':' ', 448 oidp->oid_kind & CTLFLAG_WR ? 'W':' '); 449 450 if (oidp->oid_handler) 451 printf(" *Handler"); 452 453 switch (oidp->oid_kind & CTLTYPE) { 454 case CTLTYPE_NODE: 455 printf(" Node\n"); 456 if (!oidp->oid_handler) { 457 sysctl_sysctl_debug_dump_node( 458 oidp->oid_arg1, i+2); 459 } 460 break; 461 case CTLTYPE_INT: printf(" Int\n"); break; 462 case CTLTYPE_STRING: printf(" String\n"); break; 463 case CTLTYPE_QUAD: printf(" Quad\n"); break; 464 case CTLTYPE_OPAQUE: printf(" Opaque/struct\n"); break; 465 default: printf("\n"); 466 } 467 468 } 469 } 470 471 static int 472 sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) 473 { 474 int error; 475 476 error = suser(req->td); 477 if (error) 478 return error; 479 sysctl_sysctl_debug_dump_node(&sysctl__children, 0); 480 return ENOENT; 481 } 482 483 SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD, 484 0, 0, sysctl_sysctl_debug, "-", ""); 485 486 static int 487 sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) 488 { 489 int *name = (int *) arg1; 490 u_int namelen = arg2; 491 int error = 0; 492 struct sysctl_oid *oid; 493 struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; 494 char buf[10]; 495 496 while (namelen) { 497 if (!lsp) { 498 snprintf(buf,sizeof(buf),"%d",*name); 499 if (req->oldidx) 500 error = SYSCTL_OUT(req, ".", 1); 501 if (!error) 502 error = SYSCTL_OUT(req, buf, strlen(buf)); 503 if (error) 504 return (error); 505 namelen--; 506 name++; 507 continue; 508 } 509 lsp2 = 0; 510 SLIST_FOREACH(oid, lsp, oid_link) { 511 if (oid->oid_number != *name) 512 continue; 513 514 if (req->oldidx) 515 error = SYSCTL_OUT(req, ".", 1); 516 if (!error) 517 error = SYSCTL_OUT(req, oid->oid_name, 518 strlen(oid->oid_name)); 519 if (error) 520 return (error); 521 522 namelen--; 523 name++; 524 525 if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) 526 break; 527 528 if (oid->oid_handler) 529 break; 530 531 lsp2 = (struct sysctl_oid_list *)oid->oid_arg1; 532 break; 533 } 534 lsp = lsp2; 535 } 536 return (SYSCTL_OUT(req, "", 1)); 537 } 538 539 SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD, sysctl_sysctl_name, ""); 540 541 static int 542 sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, 543 int *next, int *len, int level, struct sysctl_oid **oidpp) 544 { 545 struct sysctl_oid *oidp; 546 547 *len = level; 548 SLIST_FOREACH(oidp, lsp, oid_link) { 549 *next = oidp->oid_number; 550 *oidpp = oidp; 551 552 if (!namelen) { 553 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 554 return 0; 555 if (oidp->oid_handler) 556 /* We really should call the handler here...*/ 557 return 0; 558 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 559 if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, 560 len, level+1, oidpp)) 561 return 0; 562 goto emptynode; 563 } 564 565 if (oidp->oid_number < *name) 566 continue; 567 568 if (oidp->oid_number > *name) { 569 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 570 return 0; 571 if (oidp->oid_handler) 572 return 0; 573 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 574 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, 575 next+1, len, level+1, oidpp)) 576 return (0); 577 goto next; 578 } 579 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 580 continue; 581 582 if (oidp->oid_handler) 583 continue; 584 585 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 586 if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, 587 len, level+1, oidpp)) 588 return (0); 589 next: 590 namelen = 1; 591 *len = level; 592 emptynode: 593 *len = level; 594 } 595 return 1; 596 } 597 598 static int 599 sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) 600 { 601 int *name = (int *) arg1; 602 u_int namelen = arg2; 603 int i, j, error; 604 struct sysctl_oid *oid; 605 struct sysctl_oid_list *lsp = &sysctl__children; 606 int newoid[CTL_MAXNAME]; 607 608 i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); 609 if (i) 610 return ENOENT; 611 error = SYSCTL_OUT(req, newoid, j * sizeof (int)); 612 return (error); 613 } 614 615 SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD, sysctl_sysctl_next, ""); 616 617 static int 618 name2oid (char *name, int *oid, int *len, struct sysctl_oid **oidpp) 619 { 620 int i; 621 struct sysctl_oid *oidp; 622 struct sysctl_oid_list *lsp = &sysctl__children; 623 char *p; 624 625 if (!*name) 626 return ENOENT; 627 628 p = name + strlen(name) - 1 ; 629 if (*p == '.') 630 *p = '\0'; 631 632 *len = 0; 633 634 for (p = name; *p && *p != '.'; p++) 635 ; 636 i = *p; 637 if (i == '.') 638 *p = '\0'; 639 640 oidp = SLIST_FIRST(lsp); 641 642 while (oidp && *len < CTL_MAXNAME) { 643 if (strcmp(name, oidp->oid_name)) { 644 oidp = SLIST_NEXT(oidp, oid_link); 645 continue; 646 } 647 *oid++ = oidp->oid_number; 648 (*len)++; 649 650 if (!i) { 651 if (oidpp) 652 *oidpp = oidp; 653 return (0); 654 } 655 656 if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) 657 break; 658 659 if (oidp->oid_handler) 660 break; 661 662 lsp = (struct sysctl_oid_list *)oidp->oid_arg1; 663 oidp = SLIST_FIRST(lsp); 664 name = p+1; 665 for (p = name; *p && *p != '.'; p++) 666 ; 667 i = *p; 668 if (i == '.') 669 *p = '\0'; 670 } 671 return ENOENT; 672 } 673 674 static int 675 sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) 676 { 677 char *p; 678 int error, oid[CTL_MAXNAME], len; 679 struct sysctl_oid *op = 0; 680 681 if (!req->newlen) 682 return ENOENT; 683 if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ 684 return (ENAMETOOLONG); 685 686 p = malloc(req->newlen+1, M_SYSCTL, M_WAITOK); 687 688 error = SYSCTL_IN(req, p, req->newlen); 689 if (error) { 690 free(p, M_SYSCTL); 691 return (error); 692 } 693 694 p [req->newlen] = '\0'; 695 696 error = name2oid(p, oid, &len, &op); 697 698 free(p, M_SYSCTL); 699 700 if (error) 701 return (error); 702 703 error = SYSCTL_OUT(req, oid, len * sizeof *oid); 704 return (error); 705 } 706 707 SYSCTL_PROC(_sysctl, 3, name2oid, CTLFLAG_RW|CTLFLAG_ANYBODY, 0, 0, 708 sysctl_sysctl_name2oid, "I", ""); 709 710 static int 711 sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) 712 { 713 struct sysctl_oid *oid; 714 int error; 715 716 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 717 if (error) 718 return (error); 719 720 if (!oid->oid_fmt) 721 return (ENOENT); 722 error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); 723 if (error) 724 return (error); 725 error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); 726 return (error); 727 } 728 729 730 SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD, sysctl_sysctl_oidfmt, ""); 731 732 static int 733 sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) 734 { 735 struct sysctl_oid *oid; 736 int error; 737 738 error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); 739 if (error) 740 return (error); 741 742 if (!oid->oid_descr) 743 return (ENOENT); 744 error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); 745 return (error); 746 } 747 748 SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD, sysctl_sysctl_oiddescr, ""); 749 750 /* 751 * Default "handler" functions. 752 */ 753 754 /* 755 * Handle an int, signed or unsigned. 756 * Two cases: 757 * a variable: point arg1 at it. 758 * a constant: pass it in arg2. 759 */ 760 761 int 762 sysctl_handle_int(SYSCTL_HANDLER_ARGS) 763 { 764 int error = 0; 765 766 if (arg1) 767 error = SYSCTL_OUT(req, arg1, sizeof(int)); 768 else 769 error = SYSCTL_OUT(req, &arg2, sizeof(int)); 770 771 if (error || !req->newptr) 772 return (error); 773 774 if (!arg1) 775 error = EPERM; 776 else 777 error = SYSCTL_IN(req, arg1, sizeof(int)); 778 return (error); 779 } 780 781 /* 782 * Handle a long, signed or unsigned. arg1 points to it. 783 */ 784 785 int 786 sysctl_handle_long(SYSCTL_HANDLER_ARGS) 787 { 788 int error = 0; 789 790 if (!arg1) 791 return (EINVAL); 792 error = SYSCTL_OUT(req, arg1, sizeof(long)); 793 794 if (error || !req->newptr) 795 return (error); 796 797 error = SYSCTL_IN(req, arg1, sizeof(long)); 798 return (error); 799 } 800 801 /* 802 * Handle a quad, signed or unsigned. arg1 points to it. 803 */ 804 805 int 806 sysctl_handle_quad(SYSCTL_HANDLER_ARGS) 807 { 808 int error = 0; 809 810 if (!arg1) 811 return (EINVAL); 812 error = SYSCTL_OUT(req, arg1, sizeof(quad_t)); 813 814 if (error || !req->newptr) 815 return (error); 816 817 error = SYSCTL_IN(req, arg1, sizeof(quad_t)); 818 return (error); 819 } 820 821 /* 822 * Handle our generic '\0' terminated 'C' string. 823 * Two cases: 824 * a variable string: point arg1 at it, arg2 is max length. 825 * a constant string: point arg1 at it, arg2 is zero. 826 */ 827 828 int 829 sysctl_handle_string(SYSCTL_HANDLER_ARGS) 830 { 831 int error=0; 832 833 error = SYSCTL_OUT(req, arg1, strlen((char *)arg1)+1); 834 835 if (error || !req->newptr) 836 return (error); 837 838 if ((req->newlen - req->newidx) >= arg2) { 839 error = EINVAL; 840 } else { 841 arg2 = (req->newlen - req->newidx); 842 error = SYSCTL_IN(req, arg1, arg2); 843 ((char *)arg1)[arg2] = '\0'; 844 } 845 846 return (error); 847 } 848 849 /* 850 * Handle any kind of opaque data. 851 * arg1 points to it, arg2 is the size. 852 */ 853 854 int 855 sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) 856 { 857 int error; 858 859 error = SYSCTL_OUT(req, arg1, arg2); 860 861 if (error || !req->newptr) 862 return (error); 863 864 error = SYSCTL_IN(req, arg1, arg2); 865 866 return (error); 867 } 868 869 /* 870 * Transfer functions to/from kernel space. 871 * XXX: rather untested at this point 872 */ 873 static int 874 sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) 875 { 876 size_t i = 0; 877 878 if (req->oldptr) { 879 i = l; 880 if (i > req->oldlen - req->oldidx) 881 i = req->oldlen - req->oldidx; 882 if (i > 0) 883 bcopy(p, (char *)req->oldptr + req->oldidx, i); 884 } 885 req->oldidx += l; 886 if (req->oldptr && i != l) 887 return (ENOMEM); 888 return (0); 889 } 890 891 static int 892 sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) 893 { 894 895 if (!req->newptr) 896 return 0; 897 if (req->newlen - req->newidx < l) 898 return (EINVAL); 899 bcopy((char *)req->newptr + req->newidx, p, l); 900 req->newidx += l; 901 return (0); 902 } 903 904 int 905 kernel_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval) 906 { 907 int error = 0; 908 struct sysctl_req req; 909 910 bzero(&req, sizeof req); 911 912 req.td = curthread; 913 914 if (oldlenp) { 915 req.oldlen = *oldlenp; 916 } 917 918 if (old) { 919 req.oldptr = old; 920 } 921 922 if (new != NULL) { 923 req.newlen = newlen; 924 req.newptr = new; 925 } 926 927 req.oldfunc = sysctl_old_kernel; 928 req.newfunc = sysctl_new_kernel; 929 req.lock = 1; 930 931 /* XXX this should probably be done in a general way */ 932 while (memlock.sl_lock) { 933 memlock.sl_want = 1; 934 (void) tsleep((caddr_t)&memlock, 0, "sysctl", 0); 935 memlock.sl_locked++; 936 } 937 memlock.sl_lock = 1; 938 939 error = sysctl_root(0, name, namelen, &req); 940 941 if (req.lock == 2) 942 vsunlock(req.oldptr, req.oldlen); 943 944 memlock.sl_lock = 0; 945 946 if (memlock.sl_want) { 947 memlock.sl_want = 0; 948 wakeup((caddr_t)&memlock); 949 } 950 951 if (error && error != ENOMEM) 952 return (error); 953 954 if (retval) { 955 if (req.oldptr && req.oldidx > req.oldlen) 956 *retval = req.oldlen; 957 else 958 *retval = req.oldidx; 959 } 960 return (error); 961 } 962 963 int 964 kernel_sysctlbyname(char *name, void *old, size_t *oldlenp, 965 void *new, size_t newlen, size_t *retval) 966 { 967 int oid[CTL_MAXNAME]; 968 size_t oidlen, plen; 969 int error; 970 971 oid[0] = 0; /* sysctl internal magic */ 972 oid[1] = 3; /* name2oid */ 973 oidlen = sizeof(oid); 974 975 error = kernel_sysctl(oid, 2, oid, &oidlen, (void *)name, 976 strlen(name), &plen); 977 if (error) 978 return (error); 979 980 error = kernel_sysctl(oid, plen / sizeof(int), old, oldlenp, 981 new, newlen, retval); 982 return (error); 983 } 984 985 /* 986 * Transfer function to/from user space. 987 */ 988 static int 989 sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) 990 { 991 int error = 0; 992 size_t i = 0; 993 994 if (req->lock == 1 && req->oldptr) { 995 vslock(req->oldptr, req->oldlen); 996 req->lock = 2; 997 } 998 if (req->oldptr) { 999 i = l; 1000 if (i > req->oldlen - req->oldidx) 1001 i = req->oldlen - req->oldidx; 1002 if (i > 0) 1003 error = copyout(p, (char *)req->oldptr + req->oldidx, 1004 i); 1005 } 1006 req->oldidx += l; 1007 if (error) 1008 return (error); 1009 if (req->oldptr && i < l) 1010 return (ENOMEM); 1011 return (0); 1012 } 1013 1014 static int 1015 sysctl_new_user(struct sysctl_req *req, void *p, size_t l) 1016 { 1017 int error; 1018 1019 if (!req->newptr) 1020 return 0; 1021 if (req->newlen - req->newidx < l) 1022 return (EINVAL); 1023 error = copyin((char *)req->newptr + req->newidx, p, l); 1024 req->newidx += l; 1025 return (error); 1026 } 1027 1028 int 1029 sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, 1030 int *nindx, struct sysctl_req *req) 1031 { 1032 struct sysctl_oid *oid; 1033 int indx; 1034 1035 oid = SLIST_FIRST(&sysctl__children); 1036 indx = 0; 1037 while (oid && indx < CTL_MAXNAME) { 1038 if (oid->oid_number == name[indx]) { 1039 indx++; 1040 if (oid->oid_kind & CTLFLAG_NOLOCK) 1041 req->lock = 0; 1042 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1043 if (oid->oid_handler != NULL || 1044 indx == namelen) { 1045 *noid = oid; 1046 if (nindx != NULL) 1047 *nindx = indx; 1048 return (0); 1049 } 1050 oid = SLIST_FIRST( 1051 (struct sysctl_oid_list *)oid->oid_arg1); 1052 } else if (indx == namelen) { 1053 *noid = oid; 1054 if (nindx != NULL) 1055 *nindx = indx; 1056 return (0); 1057 } else { 1058 return (ENOTDIR); 1059 } 1060 } else { 1061 oid = SLIST_NEXT(oid, oid_link); 1062 } 1063 } 1064 return (ENOENT); 1065 } 1066 1067 /* 1068 * Traverse our tree, and find the right node, execute whatever it points 1069 * to, and return the resulting error code. 1070 */ 1071 1072 int 1073 sysctl_root(SYSCTL_HANDLER_ARGS) 1074 { 1075 struct thread *td = req->td; 1076 struct proc *p = td ? td->td_proc : NULL; 1077 struct sysctl_oid *oid; 1078 int error, indx; 1079 1080 error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); 1081 if (error) 1082 return (error); 1083 1084 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { 1085 /* 1086 * You can't call a sysctl when it's a node, but has 1087 * no handler. Inform the user that it's a node. 1088 * The indx may or may not be the same as namelen. 1089 */ 1090 if (oid->oid_handler == NULL) 1091 return (EISDIR); 1092 } 1093 1094 /* If writing isn't allowed */ 1095 if (req->newptr && (!(oid->oid_kind & CTLFLAG_WR) || 1096 ((oid->oid_kind & CTLFLAG_SECURE) && securelevel > 0))) 1097 return (EPERM); 1098 1099 /* Most likely only root can write */ 1100 if (!(oid->oid_kind & CTLFLAG_ANYBODY) && req->newptr && p && 1101 (error = suser_cred(p->p_ucred, 1102 (oid->oid_kind & CTLFLAG_PRISON) ? PRISON_ROOT : 0))) 1103 return (error); 1104 1105 if (!oid->oid_handler) 1106 return EINVAL; 1107 1108 if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) 1109 error = oid->oid_handler(oid, (int *)arg1 + indx, arg2 - indx, 1110 req); 1111 else 1112 error = oid->oid_handler(oid, oid->oid_arg1, oid->oid_arg2, 1113 req); 1114 return (error); 1115 } 1116 1117 int 1118 __sysctl(struct sysctl_args *uap) 1119 { 1120 int error, i, name[CTL_MAXNAME]; 1121 size_t j; 1122 1123 if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) 1124 return (EINVAL); 1125 1126 error = copyin(uap->name, &name, uap->namelen * sizeof(int)); 1127 if (error) 1128 return (error); 1129 1130 error = userland_sysctl(name, uap->namelen, 1131 uap->old, uap->oldlenp, 0, 1132 uap->new, uap->newlen, &j); 1133 if (error && error != ENOMEM) 1134 return (error); 1135 if (uap->oldlenp) { 1136 i = copyout(&j, uap->oldlenp, sizeof(j)); 1137 if (i) 1138 return (i); 1139 } 1140 return (error); 1141 } 1142 1143 /* 1144 * This is used from various compatibility syscalls too. That's why name 1145 * must be in kernel space. 1146 */ 1147 int 1148 userland_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval) 1149 { 1150 int error = 0; 1151 struct sysctl_req req, req2; 1152 1153 bzero(&req, sizeof req); 1154 1155 if (oldlenp) { 1156 if (inkernel) { 1157 req.oldlen = *oldlenp; 1158 } else { 1159 error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); 1160 if (error) 1161 return (error); 1162 } 1163 } 1164 1165 if (old) { 1166 if (!useracc(old, req.oldlen, VM_PROT_WRITE)) 1167 return (EFAULT); 1168 req.oldptr= old; 1169 } 1170 1171 if (new != NULL) { 1172 if (!useracc(new, req.newlen, VM_PROT_READ)) 1173 return (EFAULT); 1174 req.newlen = newlen; 1175 req.newptr = new; 1176 } 1177 1178 req.oldfunc = sysctl_old_user; 1179 req.newfunc = sysctl_new_user; 1180 req.lock = 1; 1181 req.td = curthread; 1182 1183 /* XXX this should probably be done in a general way */ 1184 while (memlock.sl_lock) { 1185 memlock.sl_want = 1; 1186 (void) tsleep((caddr_t)&memlock, 0, "sysctl", 0); 1187 memlock.sl_locked++; 1188 } 1189 memlock.sl_lock = 1; 1190 1191 do { 1192 req2 = req; 1193 error = sysctl_root(0, name, namelen, &req2); 1194 } while (error == EAGAIN); 1195 1196 req = req2; 1197 if (req.lock == 2) 1198 vsunlock(req.oldptr, req.oldlen); 1199 1200 memlock.sl_lock = 0; 1201 1202 if (memlock.sl_want) { 1203 memlock.sl_want = 0; 1204 wakeup((caddr_t)&memlock); 1205 } 1206 1207 if (error && error != ENOMEM) 1208 return (error); 1209 1210 if (retval) { 1211 if (req.oldptr && req.oldidx > req.oldlen) 1212 *retval = req.oldlen; 1213 else 1214 *retval = req.oldidx; 1215 } 1216 return (error); 1217 } 1218