| 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 | #include <sys/sbuf.h> |
| 50 | |
| 51 | #include <sys/mplock2.h> |
| 52 | |
| 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 | /* |
| 60 | * The sysctllock protects the MIB tree. It also protects sysctl |
| 61 | * contexts used with dynamic sysctls. The sysctl_register_oid() and |
| 62 | * sysctl_unregister_oid() routines require the sysctllock to already |
| 63 | * be held, so the sysctl_lock() and sysctl_unlock() routines are |
| 64 | * provided for the few places in the kernel which need to use that |
| 65 | * API rather than using the dynamic API. Use of the dynamic API is |
| 66 | * strongly encouraged for most code. |
| 67 | * |
| 68 | * The sysctlmemlock is used to limit the amount of user memory wired for |
| 69 | * sysctl requests. This is implemented by serializing any userland |
| 70 | * sysctl requests larger than a single page via an exclusive lock. |
| 71 | */ |
| 72 | struct lock sysctllock; |
| 73 | static struct lock sysctlmemlock; |
| 74 | |
| 75 | #define SYSCTL_XLOCK() lockmgr(&sysctllock, LK_EXCLUSIVE) |
| 76 | #define SYSCTL_XUNLOCK() lockmgr(&sysctllock, LK_RELEASE) |
| 77 | #define SYSCTL_ASSERT_XLOCKED() KKASSERT(lockstatus(&sysctllock, curthread) != 0) |
| 78 | #define SYSCTL_INIT() lockinit(&sysctllock, \ |
| 79 | "sysctl lock", 0, LK_CANRECURSE) |
| 80 | #define SYSCTL_SLEEP(ch, wmesg, timo) \ |
| 81 | lksleep(ch, &sysctllock, 0, wmesg, timo) |
| 82 | |
| 83 | static int sysctl_root(SYSCTL_HANDLER_ARGS); |
| 84 | static void sysctl_register_oid_int(struct sysctl_oid *oipd); |
| 85 | static void sysctl_unregister_oid_int(struct sysctl_oid *oipd); |
| 86 | |
| 87 | struct sysctl_oid_list sysctl__children; /* root list */ |
| 88 | |
| 89 | static int sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, |
| 90 | int recurse); |
| 91 | |
| 92 | static struct sysctl_oid * |
| 93 | sysctl_find_oidname(const char *name, struct sysctl_oid_list *list, int lock) |
| 94 | { |
| 95 | struct sysctl_oid *oidp; |
| 96 | |
| 97 | SLIST_FOREACH(oidp, list, oid_link) { |
| 98 | if (strcmp(oidp->oid_name, name) == 0) { |
| 99 | break; |
| 100 | } |
| 101 | } |
| 102 | return (oidp); |
| 103 | } |
| 104 | |
| 105 | /* |
| 106 | * Initialization of the MIB tree. |
| 107 | * |
| 108 | * Order by number in each list. |
| 109 | */ |
| 110 | |
| 111 | void |
| 112 | sysctl_register_oid(struct sysctl_oid *oidp) |
| 113 | { |
| 114 | SYSCTL_XLOCK(); |
| 115 | sysctl_register_oid_int(oidp); |
| 116 | SYSCTL_XUNLOCK(); |
| 117 | } |
| 118 | |
| 119 | static void |
| 120 | sysctl_register_oid_int(struct sysctl_oid *oidp) |
| 121 | { |
| 122 | struct sysctl_oid_list *parent = oidp->oid_parent; |
| 123 | struct sysctl_oid *p; |
| 124 | struct sysctl_oid *q; |
| 125 | |
| 126 | /* |
| 127 | * First check if another oid with the same name already |
| 128 | * exists in the parent's list. |
| 129 | */ |
| 130 | p = sysctl_find_oidname(oidp->oid_name, parent, 0); |
| 131 | if (p != NULL) { |
| 132 | if ((p->oid_kind & CTLTYPE) == CTLTYPE_NODE) |
| 133 | p->oid_refcnt++; |
| 134 | else |
| 135 | kprintf("can't re-use a leaf (%s)!\n", p->oid_name); |
| 136 | return; |
| 137 | } |
| 138 | |
| 139 | /* |
| 140 | * If this oid has a number OID_AUTO, give it a number which |
| 141 | * is greater than any current oid. Make sure it is at least |
| 142 | * 256 to leave space for pre-assigned oid numbers. |
| 143 | */ |
| 144 | if (oidp->oid_number == OID_AUTO) { |
| 145 | int newoid = 0x100; /* minimum AUTO oid */ |
| 146 | |
| 147 | /* |
| 148 | * Adjust based on highest oid in parent list |
| 149 | */ |
| 150 | SLIST_FOREACH(p, parent, oid_link) { |
| 151 | if (newoid <= p->oid_number) |
| 152 | newoid = p->oid_number + 1; |
| 153 | } |
| 154 | oidp->oid_number = newoid; |
| 155 | } |
| 156 | |
| 157 | /* |
| 158 | * Insert the oid into the parent's list in order. |
| 159 | */ |
| 160 | q = NULL; |
| 161 | SLIST_FOREACH(p, parent, oid_link) { |
| 162 | if (oidp->oid_number < p->oid_number) |
| 163 | break; |
| 164 | q = p; |
| 165 | } |
| 166 | if (q) |
| 167 | SLIST_INSERT_AFTER(q, oidp, oid_link); |
| 168 | else |
| 169 | SLIST_INSERT_HEAD(parent, oidp, oid_link); |
| 170 | } |
| 171 | |
| 172 | void |
| 173 | sysctl_unregister_oid(struct sysctl_oid *oidp) |
| 174 | { |
| 175 | SYSCTL_XLOCK(); |
| 176 | sysctl_unregister_oid_int(oidp); |
| 177 | SYSCTL_XUNLOCK(); |
| 178 | } |
| 179 | |
| 180 | static void |
| 181 | sysctl_unregister_oid_int(struct sysctl_oid *oidp) |
| 182 | { |
| 183 | struct sysctl_oid *p; |
| 184 | |
| 185 | if (oidp->oid_number == OID_AUTO) |
| 186 | panic("Trying to unregister OID_AUTO entry: %p", oidp); |
| 187 | |
| 188 | SLIST_FOREACH(p, oidp->oid_parent, oid_link) { |
| 189 | if (p != oidp) |
| 190 | continue; |
| 191 | SLIST_REMOVE(oidp->oid_parent, oidp, sysctl_oid, oid_link); |
| 192 | return; |
| 193 | } |
| 194 | |
| 195 | /* |
| 196 | * This can happen when a module fails to register and is |
| 197 | * being unloaded afterwards. It should not be a panic() |
| 198 | * for normal use. |
| 199 | */ |
| 200 | kprintf("%s: failed to unregister sysctl\n", __func__); |
| 201 | } |
| 202 | |
| 203 | /* Initialize a new context to keep track of dynamically added sysctls. */ |
| 204 | int |
| 205 | sysctl_ctx_init(struct sysctl_ctx_list *c) |
| 206 | { |
| 207 | if (c == NULL) |
| 208 | return(EINVAL); |
| 209 | TAILQ_INIT(c); |
| 210 | return(0); |
| 211 | } |
| 212 | |
| 213 | /* Free the context, and destroy all dynamic oids registered in this context */ |
| 214 | int |
| 215 | sysctl_ctx_free(struct sysctl_ctx_list *clist) |
| 216 | { |
| 217 | struct sysctl_ctx_entry *e, *e1; |
| 218 | int error; |
| 219 | |
| 220 | error = 0; |
| 221 | /* |
| 222 | * First perform a "dry run" to check if it's ok to remove oids. |
| 223 | * XXX FIXME |
| 224 | * XXX This algorithm is a hack. But I don't know any |
| 225 | * XXX better solution for now... |
| 226 | */ |
| 227 | SYSCTL_XLOCK(); |
| 228 | TAILQ_FOREACH(e, clist, link) { |
| 229 | error = sysctl_remove_oid_locked(e->entry, 0, 0); |
| 230 | if (error) |
| 231 | break; |
| 232 | } |
| 233 | /* |
| 234 | * Restore deregistered entries, either from the end, |
| 235 | * or from the place where error occured. |
| 236 | * e contains the entry that was not unregistered |
| 237 | */ |
| 238 | if (error) |
| 239 | e1 = TAILQ_PREV(e, sysctl_ctx_list, link); |
| 240 | else |
| 241 | e1 = TAILQ_LAST(clist, sysctl_ctx_list); |
| 242 | while (e1 != NULL) { |
| 243 | sysctl_register_oid(e1->entry); |
| 244 | e1 = TAILQ_PREV(e1, sysctl_ctx_list, link); |
| 245 | } |
| 246 | if (error) { |
| 247 | SYSCTL_XUNLOCK(); |
| 248 | return(EBUSY); |
| 249 | } |
| 250 | /* Now really delete the entries */ |
| 251 | e = TAILQ_FIRST(clist); |
| 252 | while (e != NULL) { |
| 253 | e1 = TAILQ_NEXT(e, link); |
| 254 | error = sysctl_remove_oid_locked(e->entry, 1, 0); |
| 255 | if (error) |
| 256 | panic("sysctl_remove_oid: corrupt tree, entry: %s", |
| 257 | e->entry->oid_name); |
| 258 | kfree(e, M_SYSCTLOID); |
| 259 | e = e1; |
| 260 | } |
| 261 | SYSCTL_XUNLOCK(); |
| 262 | return (error); |
| 263 | } |
| 264 | |
| 265 | /* Add an entry to the context */ |
| 266 | struct sysctl_ctx_entry * |
| 267 | sysctl_ctx_entry_add(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) |
| 268 | { |
| 269 | struct sysctl_ctx_entry *e; |
| 270 | |
| 271 | SYSCTL_ASSERT_XLOCKED(); |
| 272 | if (clist == NULL || oidp == NULL) |
| 273 | return(NULL); |
| 274 | e = kmalloc(sizeof(struct sysctl_ctx_entry), M_SYSCTLOID, M_WAITOK); |
| 275 | e->entry = oidp; |
| 276 | TAILQ_INSERT_HEAD(clist, e, link); |
| 277 | return (e); |
| 278 | } |
| 279 | |
| 280 | /* Find an entry in the context */ |
| 281 | struct sysctl_ctx_entry * |
| 282 | sysctl_ctx_entry_find(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) |
| 283 | { |
| 284 | struct sysctl_ctx_entry *e; |
| 285 | |
| 286 | SYSCTL_ASSERT_XLOCKED(); |
| 287 | if (clist == NULL || oidp == NULL) |
| 288 | return(NULL); |
| 289 | TAILQ_FOREACH(e, clist, link) { |
| 290 | if(e->entry == oidp) |
| 291 | return(e); |
| 292 | } |
| 293 | return (e); |
| 294 | } |
| 295 | |
| 296 | /* |
| 297 | * Delete an entry from the context. |
| 298 | * NOTE: this function doesn't free oidp! You have to remove it |
| 299 | * with sysctl_remove_oid(). |
| 300 | */ |
| 301 | int |
| 302 | sysctl_ctx_entry_del(struct sysctl_ctx_list *clist, struct sysctl_oid *oidp) |
| 303 | { |
| 304 | struct sysctl_ctx_entry *e; |
| 305 | |
| 306 | if (clist == NULL || oidp == NULL) |
| 307 | return (EINVAL); |
| 308 | SYSCTL_XLOCK(); |
| 309 | e = sysctl_ctx_entry_find(clist, oidp); |
| 310 | if (e != NULL) { |
| 311 | TAILQ_REMOVE(clist, e, link); |
| 312 | SYSCTL_XUNLOCK(); |
| 313 | kfree(e, M_SYSCTLOID); |
| 314 | return (0); |
| 315 | } else { |
| 316 | SYSCTL_XUNLOCK(); |
| 317 | return (ENOENT); |
| 318 | } |
| 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 | int error; |
| 331 | |
| 332 | SYSCTL_XLOCK(); |
| 333 | error = sysctl_remove_oid_locked(oidp, del, recurse); |
| 334 | SYSCTL_XUNLOCK(); |
| 335 | return (error); |
| 336 | } |
| 337 | |
| 338 | static int |
| 339 | sysctl_remove_oid_locked(struct sysctl_oid *oidp, int del, int recurse) |
| 340 | { |
| 341 | struct sysctl_oid *p, *tmp; |
| 342 | int error; |
| 343 | |
| 344 | SYSCTL_ASSERT_XLOCKED(); |
| 345 | if (oidp == NULL) |
| 346 | return(EINVAL); |
| 347 | if ((oidp->oid_kind & CTLFLAG_DYN) == 0) { |
| 348 | kprintf("can't remove non-dynamic nodes!\n"); |
| 349 | return (EINVAL); |
| 350 | } |
| 351 | /* |
| 352 | * WARNING: normal method to do this should be through |
| 353 | * sysctl_ctx_free(). Use recursing as the last resort |
| 354 | * method to purge your sysctl tree of leftovers... |
| 355 | * However, if some other code still references these nodes, |
| 356 | * it will panic. |
| 357 | */ |
| 358 | if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { |
| 359 | if (oidp->oid_refcnt == 1) { |
| 360 | SLIST_FOREACH_MUTABLE(p, |
| 361 | SYSCTL_CHILDREN(oidp), oid_link, tmp) { |
| 362 | if (!recurse) { |
| 363 | kprintf("Warning: failed attempt to " |
| 364 | "remove oid %s with child %s\n", |
| 365 | oidp->oid_name, p->oid_name); |
| 366 | return (ENOTEMPTY); |
| 367 | } |
| 368 | error = sysctl_remove_oid_locked(p, del, |
| 369 | recurse); |
| 370 | if (error) |
| 371 | return (error); |
| 372 | } |
| 373 | if (del) |
| 374 | kfree(SYSCTL_CHILDREN(oidp), M_SYSCTLOID); |
| 375 | } |
| 376 | } |
| 377 | if (oidp->oid_refcnt > 1 ) { |
| 378 | oidp->oid_refcnt--; |
| 379 | } else { |
| 380 | if (oidp->oid_refcnt == 0) { |
| 381 | kprintf("Warning: bad oid_refcnt=%u (%s)!\n", |
| 382 | oidp->oid_refcnt, oidp->oid_name); |
| 383 | return (EINVAL); |
| 384 | } |
| 385 | sysctl_unregister_oid(oidp); |
| 386 | if (del) { |
| 387 | /* |
| 388 | * Wait for all threads running the handler to drain. |
| 389 | * This preserves the previous behavior when the |
| 390 | * sysctl lock was held across a handler invocation, |
| 391 | * and is necessary for module unload correctness. |
| 392 | */ |
| 393 | while (oidp->oid_running > 0) { |
| 394 | oidp->oid_kind |= CTLFLAG_DYING; |
| 395 | SYSCTL_SLEEP(&oidp->oid_running, "oidrm", 0); |
| 396 | } |
| 397 | if (oidp->oid_descr) |
| 398 | kfree(__DECONST(char *, oidp->oid_descr), |
| 399 | M_SYSCTLOID); |
| 400 | kfree(__DECONST(char *, oidp->oid_name), M_SYSCTLOID); |
| 401 | kfree(oidp, M_SYSCTLOID); |
| 402 | } |
| 403 | } |
| 404 | return (0); |
| 405 | } |
| 406 | |
| 407 | int |
| 408 | sysctl_remove_name(struct sysctl_oid *parent, const char *name, |
| 409 | int del, int recurse) |
| 410 | { |
| 411 | struct sysctl_oid *p, *tmp; |
| 412 | int error; |
| 413 | |
| 414 | error = ENOENT; |
| 415 | SYSCTL_XLOCK(); |
| 416 | SLIST_FOREACH_MUTABLE(p, SYSCTL_CHILDREN(parent), oid_link, tmp) { |
| 417 | if (strcmp(p->oid_name, name) == 0) { |
| 418 | error = sysctl_remove_oid_locked(p, del, recurse); |
| 419 | break; |
| 420 | } |
| 421 | } |
| 422 | SYSCTL_XUNLOCK(); |
| 423 | |
| 424 | return (error); |
| 425 | } |
| 426 | |
| 427 | /* |
| 428 | * Create new sysctls at run time. |
| 429 | * clist may point to a valid context initialized with sysctl_ctx_init(). |
| 430 | */ |
| 431 | struct sysctl_oid * |
| 432 | sysctl_add_oid(struct sysctl_ctx_list *clist, struct sysctl_oid_list *parent, |
| 433 | int number, const char *name, int kind, void *arg1, int arg2, |
| 434 | int (*handler)(SYSCTL_HANDLER_ARGS), const char *fmt, const char *descr) |
| 435 | { |
| 436 | struct sysctl_oid *oidp; |
| 437 | ssize_t len; |
| 438 | char *newname; |
| 439 | |
| 440 | /* You have to hook up somewhere.. */ |
| 441 | if (parent == NULL) |
| 442 | return(NULL); |
| 443 | SYSCTL_XLOCK(); |
| 444 | /* Check if the node already exists, otherwise create it */ |
| 445 | oidp = sysctl_find_oidname(name, parent, 0); |
| 446 | if (oidp != NULL) { |
| 447 | if ((oidp->oid_kind & CTLTYPE) == CTLTYPE_NODE) { |
| 448 | oidp->oid_refcnt++; |
| 449 | /* Update the context */ |
| 450 | if (clist != NULL) |
| 451 | sysctl_ctx_entry_add(clist, oidp); |
| 452 | SYSCTL_XUNLOCK(); |
| 453 | return (oidp); |
| 454 | } else { |
| 455 | kprintf("can't re-use a leaf (%s)!\n", name); |
| 456 | SYSCTL_XUNLOCK(); |
| 457 | return (NULL); |
| 458 | } |
| 459 | } |
| 460 | oidp = kmalloc(sizeof(struct sysctl_oid), M_SYSCTLOID, M_WAITOK | M_ZERO); |
| 461 | oidp->oid_parent = parent; |
| 462 | SLIST_NEXT(oidp, oid_link) = NULL; |
| 463 | oidp->oid_number = number; |
| 464 | oidp->oid_refcnt = 1; |
| 465 | len = strlen(name); |
| 466 | newname = kmalloc(len + 1, M_SYSCTLOID, M_WAITOK); |
| 467 | bcopy(name, newname, len + 1); |
| 468 | newname[len] = '\0'; |
| 469 | oidp->oid_name = newname; |
| 470 | oidp->oid_handler = handler; |
| 471 | oidp->oid_kind = CTLFLAG_DYN | kind; |
| 472 | if ((kind & CTLTYPE) == CTLTYPE_NODE) { |
| 473 | struct sysctl_oid_list *children; |
| 474 | |
| 475 | /* Allocate space for children */ |
| 476 | children = kmalloc(sizeof(*children), M_SYSCTLOID, M_WAITOK); |
| 477 | SYSCTL_SET_CHILDREN(oidp, children); |
| 478 | SLIST_INIT(children); |
| 479 | } else { |
| 480 | oidp->oid_arg1 = arg1; |
| 481 | oidp->oid_arg2 = arg2; |
| 482 | } |
| 483 | oidp->oid_fmt = fmt; |
| 484 | if (descr) { |
| 485 | int len = strlen(descr) + 1; |
| 486 | oidp->oid_descr = kmalloc(len, M_SYSCTLOID, M_WAITOK); |
| 487 | strcpy((char *)(uintptr_t)(const void *)oidp->oid_descr, descr); |
| 488 | }; |
| 489 | /* Update the context, if used */ |
| 490 | if (clist != NULL) |
| 491 | sysctl_ctx_entry_add(clist, oidp); |
| 492 | /* Register this oid */ |
| 493 | sysctl_register_oid_int(oidp); |
| 494 | SYSCTL_XUNLOCK(); |
| 495 | return (oidp); |
| 496 | } |
| 497 | |
| 498 | /* |
| 499 | * Rename an existing oid. |
| 500 | */ |
| 501 | void |
| 502 | sysctl_rename_oid(struct sysctl_oid *oidp, const char *name) |
| 503 | { |
| 504 | char *newname; |
| 505 | char *oldname; |
| 506 | |
| 507 | newname = kstrdup(name, M_SYSCTLOID); |
| 508 | SYSCTL_XLOCK(); |
| 509 | oldname = __DECONST(char *, oidp->oid_name); |
| 510 | oidp->oid_name = newname; |
| 511 | SYSCTL_XUNLOCK(); |
| 512 | kfree(oldname, M_SYSCTLOID); |
| 513 | } |
| 514 | |
| 515 | /* |
| 516 | * Register the kernel's oids on startup. |
| 517 | */ |
| 518 | SET_DECLARE(sysctl_set, struct sysctl_oid); |
| 519 | |
| 520 | static void |
| 521 | sysctl_register_all(void *arg) |
| 522 | { |
| 523 | struct sysctl_oid **oidp; |
| 524 | |
| 525 | lockinit(&sysctlmemlock, "sysctl mem", 0, LK_CANRECURSE); |
| 526 | SYSCTL_INIT(); |
| 527 | SYSCTL_XLOCK(); |
| 528 | SET_FOREACH(oidp, sysctl_set) |
| 529 | sysctl_register_oid(*oidp); |
| 530 | SYSCTL_XUNLOCK(); |
| 531 | } |
| 532 | SYSINIT(sysctl, SI_BOOT1_POST, SI_ORDER_ANY, sysctl_register_all, 0); |
| 533 | |
| 534 | /* |
| 535 | * "Staff-functions" |
| 536 | * |
| 537 | * These functions implement a presently undocumented interface |
| 538 | * used by the sysctl program to walk the tree, and get the type |
| 539 | * so it can print the value. |
| 540 | * This interface is under work and consideration, and should probably |
| 541 | * be killed with a big axe by the first person who can find the time. |
| 542 | * (be aware though, that the proper interface isn't as obvious as it |
| 543 | * may seem, there are various conflicting requirements. |
| 544 | * |
| 545 | * {0,0} kprintf the entire MIB-tree. |
| 546 | * {0,1,...} return the name of the "..." OID. |
| 547 | * {0,2,...} return the next OID. |
| 548 | * {0,3} return the OID of the name in "new" |
| 549 | * {0,4,...} return the kind & format info for the "..." OID. |
| 550 | */ |
| 551 | |
| 552 | static void |
| 553 | sysctl_sysctl_debug_dump_node(struct sysctl_oid_list *l, int i) |
| 554 | { |
| 555 | int k; |
| 556 | struct sysctl_oid *oidp; |
| 557 | |
| 558 | SYSCTL_ASSERT_XLOCKED(); |
| 559 | SLIST_FOREACH(oidp, l, oid_link) { |
| 560 | |
| 561 | for (k=0; k<i; k++) |
| 562 | kprintf(" "); |
| 563 | |
| 564 | kprintf("%d %s ", oidp->oid_number, oidp->oid_name); |
| 565 | |
| 566 | kprintf("%c%c", |
| 567 | oidp->oid_kind & CTLFLAG_RD ? 'R':' ', |
| 568 | oidp->oid_kind & CTLFLAG_WR ? 'W':' '); |
| 569 | |
| 570 | if (oidp->oid_handler) |
| 571 | kprintf(" *Handler"); |
| 572 | |
| 573 | switch (oidp->oid_kind & CTLTYPE) { |
| 574 | case CTLTYPE_NODE: |
| 575 | kprintf(" Node\n"); |
| 576 | if (!oidp->oid_handler) { |
| 577 | sysctl_sysctl_debug_dump_node( |
| 578 | oidp->oid_arg1, i+2); |
| 579 | } |
| 580 | break; |
| 581 | case CTLTYPE_INT: kprintf(" Int\n"); break; |
| 582 | case CTLTYPE_STRING: kprintf(" String\n"); break; |
| 583 | case CTLTYPE_QUAD: kprintf(" Quad\n"); break; |
| 584 | case CTLTYPE_OPAQUE: kprintf(" Opaque/struct\n"); break; |
| 585 | default: kprintf("\n"); |
| 586 | } |
| 587 | |
| 588 | } |
| 589 | } |
| 590 | |
| 591 | static int |
| 592 | sysctl_sysctl_debug(SYSCTL_HANDLER_ARGS) |
| 593 | { |
| 594 | int error; |
| 595 | |
| 596 | error = priv_check(req->td, PRIV_SYSCTL_DEBUG); |
| 597 | if (error) |
| 598 | return (error); |
| 599 | SYSCTL_XLOCK(); |
| 600 | sysctl_sysctl_debug_dump_node(&sysctl__children, 0); |
| 601 | SYSCTL_XUNLOCK(); |
| 602 | return (ENOENT); |
| 603 | } |
| 604 | |
| 605 | SYSCTL_PROC(_sysctl, 0, debug, CTLTYPE_STRING|CTLFLAG_RD, |
| 606 | 0, 0, sysctl_sysctl_debug, "-", ""); |
| 607 | |
| 608 | static int |
| 609 | sysctl_sysctl_name(SYSCTL_HANDLER_ARGS) |
| 610 | { |
| 611 | int *name = (int *) arg1; |
| 612 | u_int namelen = arg2; |
| 613 | int error = 0; |
| 614 | struct sysctl_oid *oid; |
| 615 | struct sysctl_oid_list *lsp = &sysctl__children, *lsp2; |
| 616 | char buf[10]; |
| 617 | |
| 618 | SYSCTL_XLOCK(); |
| 619 | while (namelen) { |
| 620 | if (!lsp) { |
| 621 | ksnprintf(buf, sizeof(buf), "%d", *name); |
| 622 | if (req->oldidx) |
| 623 | error = SYSCTL_OUT(req, ".", 1); |
| 624 | if (!error) |
| 625 | error = SYSCTL_OUT(req, buf, strlen(buf)); |
| 626 | if (error) |
| 627 | goto out; |
| 628 | namelen--; |
| 629 | name++; |
| 630 | continue; |
| 631 | } |
| 632 | lsp2 = NULL; |
| 633 | SLIST_FOREACH(oid, lsp, oid_link) { |
| 634 | if (oid->oid_number != *name) |
| 635 | continue; |
| 636 | |
| 637 | if (req->oldidx) |
| 638 | error = SYSCTL_OUT(req, ".", 1); |
| 639 | if (!error) |
| 640 | error = SYSCTL_OUT(req, oid->oid_name, |
| 641 | strlen(oid->oid_name)); |
| 642 | if (error) |
| 643 | goto out; |
| 644 | |
| 645 | namelen--; |
| 646 | name++; |
| 647 | |
| 648 | if ((oid->oid_kind & CTLTYPE) != CTLTYPE_NODE) |
| 649 | break; |
| 650 | |
| 651 | if (oid->oid_handler) |
| 652 | break; |
| 653 | |
| 654 | lsp2 = SYSCTL_CHILDREN(oid); |
| 655 | break; |
| 656 | } |
| 657 | lsp = lsp2; |
| 658 | } |
| 659 | error = SYSCTL_OUT(req, "", 1); |
| 660 | out: |
| 661 | SYSCTL_XUNLOCK(); |
| 662 | return (error); |
| 663 | } |
| 664 | |
| 665 | SYSCTL_NODE(_sysctl, 1, name, CTLFLAG_RD, sysctl_sysctl_name, ""); |
| 666 | |
| 667 | static int |
| 668 | sysctl_sysctl_next_ls(struct sysctl_oid_list *lsp, int *name, u_int namelen, |
| 669 | int *next, int *len, int level, struct sysctl_oid **oidpp) |
| 670 | { |
| 671 | struct sysctl_oid *oidp; |
| 672 | |
| 673 | SYSCTL_ASSERT_XLOCKED(); |
| 674 | *len = level; |
| 675 | SLIST_FOREACH(oidp, lsp, oid_link) { |
| 676 | *next = oidp->oid_number; |
| 677 | *oidpp = oidp; |
| 678 | |
| 679 | if (oidp->oid_kind & CTLFLAG_SKIP) |
| 680 | continue; |
| 681 | |
| 682 | if (!namelen) { |
| 683 | if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) |
| 684 | return (0); |
| 685 | if (oidp->oid_handler) |
| 686 | /* We really should call the handler here...*/ |
| 687 | return (0); |
| 688 | lsp = SYSCTL_CHILDREN(oidp); |
| 689 | if (!sysctl_sysctl_next_ls(lsp, 0, 0, next+1, |
| 690 | len, level+1, oidpp)) |
| 691 | return (0); |
| 692 | goto emptynode; |
| 693 | } |
| 694 | |
| 695 | if (oidp->oid_number < *name) |
| 696 | continue; |
| 697 | |
| 698 | if (oidp->oid_number > *name) { |
| 699 | if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) |
| 700 | return (0); |
| 701 | if (oidp->oid_handler) |
| 702 | return (0); |
| 703 | lsp = SYSCTL_CHILDREN(oidp); |
| 704 | if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, |
| 705 | next+1, len, level+1, oidpp)) |
| 706 | return (0); |
| 707 | goto next; |
| 708 | } |
| 709 | if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) |
| 710 | continue; |
| 711 | |
| 712 | if (oidp->oid_handler) |
| 713 | continue; |
| 714 | |
| 715 | lsp = SYSCTL_CHILDREN(oidp); |
| 716 | if (!sysctl_sysctl_next_ls(lsp, name+1, namelen-1, next+1, |
| 717 | len, level+1, oidpp)) |
| 718 | return (0); |
| 719 | next: |
| 720 | namelen = 1; |
| 721 | emptynode: |
| 722 | *len = level; |
| 723 | } |
| 724 | return (1); |
| 725 | } |
| 726 | |
| 727 | static int |
| 728 | sysctl_sysctl_next(SYSCTL_HANDLER_ARGS) |
| 729 | { |
| 730 | int *name = (int *) arg1; |
| 731 | u_int namelen = arg2; |
| 732 | int i, j, error; |
| 733 | struct sysctl_oid *oid; |
| 734 | struct sysctl_oid_list *lsp = &sysctl__children; |
| 735 | int newoid[CTL_MAXNAME]; |
| 736 | |
| 737 | i = sysctl_sysctl_next_ls(lsp, name, namelen, newoid, &j, 1, &oid); |
| 738 | if (i) |
| 739 | return ENOENT; |
| 740 | error = SYSCTL_OUT(req, newoid, j * sizeof (int)); |
| 741 | return (error); |
| 742 | } |
| 743 | |
| 744 | SYSCTL_NODE(_sysctl, 2, next, CTLFLAG_RD, sysctl_sysctl_next, ""); |
| 745 | |
| 746 | static int |
| 747 | name2oid(char *name, int *oid, int *len, struct sysctl_oid **oidpp) |
| 748 | { |
| 749 | struct sysctl_oid *oidp; |
| 750 | struct sysctl_oid_list *lsp = &sysctl__children; |
| 751 | char *p; |
| 752 | |
| 753 | SYSCTL_ASSERT_XLOCKED(); |
| 754 | |
| 755 | for (*len = 0; *len < CTL_MAXNAME;) { |
| 756 | p = strsep(&name, "."); |
| 757 | |
| 758 | oidp = SLIST_FIRST(lsp); |
| 759 | for (;; oidp = SLIST_NEXT(oidp, oid_link)) { |
| 760 | if (oidp == NULL) |
| 761 | return (ENOENT); |
| 762 | if (strcmp(p, oidp->oid_name) == 0) |
| 763 | break; |
| 764 | } |
| 765 | *oid++ = oidp->oid_number; |
| 766 | (*len)++; |
| 767 | |
| 768 | if (name == NULL || *name == '\0') { |
| 769 | if (oidpp) |
| 770 | *oidpp = oidp; |
| 771 | return (0); |
| 772 | } |
| 773 | |
| 774 | if ((oidp->oid_kind & CTLTYPE) != CTLTYPE_NODE) |
| 775 | break; |
| 776 | |
| 777 | if (oidp->oid_handler) |
| 778 | break; |
| 779 | |
| 780 | lsp = SYSCTL_CHILDREN(oidp); |
| 781 | } |
| 782 | return (ENOENT); |
| 783 | } |
| 784 | |
| 785 | static int |
| 786 | sysctl_sysctl_name2oid(SYSCTL_HANDLER_ARGS) |
| 787 | { |
| 788 | char *p; |
| 789 | int error, oid[CTL_MAXNAME], len; |
| 790 | struct sysctl_oid *op = NULL; |
| 791 | |
| 792 | if (!req->newlen) |
| 793 | return ENOENT; |
| 794 | if (req->newlen >= MAXPATHLEN) /* XXX arbitrary, undocumented */ |
| 795 | return (ENAMETOOLONG); |
| 796 | |
| 797 | p = kmalloc(req->newlen+1, M_SYSCTL, M_WAITOK); |
| 798 | |
| 799 | error = SYSCTL_IN(req, p, req->newlen); |
| 800 | if (error) { |
| 801 | kfree(p, M_SYSCTL); |
| 802 | return (error); |
| 803 | } |
| 804 | |
| 805 | p [req->newlen] = '\0'; |
| 806 | |
| 807 | error = name2oid(p, oid, &len, &op); |
| 808 | |
| 809 | kfree(p, M_SYSCTL); |
| 810 | |
| 811 | if (error) |
| 812 | return (error); |
| 813 | |
| 814 | error = SYSCTL_OUT(req, oid, len * sizeof *oid); |
| 815 | return (error); |
| 816 | } |
| 817 | |
| 818 | SYSCTL_PROC(_sysctl, 3, name2oid, CTLFLAG_RW|CTLFLAG_ANYBODY, 0, 0, |
| 819 | sysctl_sysctl_name2oid, "I", ""); |
| 820 | |
| 821 | static int |
| 822 | sysctl_sysctl_oidfmt(SYSCTL_HANDLER_ARGS) |
| 823 | { |
| 824 | struct sysctl_oid *oid; |
| 825 | int error; |
| 826 | |
| 827 | error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); |
| 828 | if (error) |
| 829 | return (error); |
| 830 | |
| 831 | if (!oid->oid_fmt) |
| 832 | return (ENOENT); |
| 833 | error = SYSCTL_OUT(req, &oid->oid_kind, sizeof(oid->oid_kind)); |
| 834 | if (error) |
| 835 | return (error); |
| 836 | error = SYSCTL_OUT(req, oid->oid_fmt, strlen(oid->oid_fmt) + 1); |
| 837 | return (error); |
| 838 | } |
| 839 | |
| 840 | |
| 841 | SYSCTL_NODE(_sysctl, 4, oidfmt, CTLFLAG_RD, sysctl_sysctl_oidfmt, ""); |
| 842 | |
| 843 | static int |
| 844 | sysctl_sysctl_oiddescr(SYSCTL_HANDLER_ARGS) |
| 845 | { |
| 846 | struct sysctl_oid *oid; |
| 847 | int error; |
| 848 | |
| 849 | error = sysctl_find_oid(arg1, arg2, &oid, NULL, req); |
| 850 | if (error) |
| 851 | return (error); |
| 852 | |
| 853 | if (!oid->oid_descr) |
| 854 | return (ENOENT); |
| 855 | error = SYSCTL_OUT(req, oid->oid_descr, strlen(oid->oid_descr) + 1); |
| 856 | return (error); |
| 857 | } |
| 858 | |
| 859 | SYSCTL_NODE(_sysctl, 5, oiddescr, CTLFLAG_RD, sysctl_sysctl_oiddescr, ""); |
| 860 | |
| 861 | /* |
| 862 | * Default "handler" functions. |
| 863 | */ |
| 864 | |
| 865 | /* |
| 866 | * Handle an int, signed or unsigned. |
| 867 | * Two cases: |
| 868 | * a variable: point arg1 at it. |
| 869 | * a constant: pass it in arg2. |
| 870 | */ |
| 871 | |
| 872 | int |
| 873 | sysctl_handle_int(SYSCTL_HANDLER_ARGS) |
| 874 | { |
| 875 | int error = 0; |
| 876 | |
| 877 | if (arg1) |
| 878 | error = SYSCTL_OUT(req, arg1, sizeof(int)); |
| 879 | else |
| 880 | error = SYSCTL_OUT(req, &arg2, sizeof(int)); |
| 881 | |
| 882 | if (error || !req->newptr) |
| 883 | return (error); |
| 884 | |
| 885 | if (!arg1) |
| 886 | error = EPERM; |
| 887 | else |
| 888 | error = SYSCTL_IN(req, arg1, sizeof(int)); |
| 889 | return (error); |
| 890 | } |
| 891 | |
| 892 | /* |
| 893 | * Handle a long, signed or unsigned. arg1 points to it. |
| 894 | */ |
| 895 | |
| 896 | int |
| 897 | sysctl_handle_long(SYSCTL_HANDLER_ARGS) |
| 898 | { |
| 899 | int error = 0; |
| 900 | |
| 901 | if (!arg1) |
| 902 | return (EINVAL); |
| 903 | error = SYSCTL_OUT(req, arg1, sizeof(long)); |
| 904 | |
| 905 | if (error || !req->newptr) |
| 906 | return (error); |
| 907 | |
| 908 | error = SYSCTL_IN(req, arg1, sizeof(long)); |
| 909 | return (error); |
| 910 | } |
| 911 | |
| 912 | /* |
| 913 | * Handle a quad, signed or unsigned. arg1 points to it. |
| 914 | */ |
| 915 | |
| 916 | int |
| 917 | sysctl_handle_quad(SYSCTL_HANDLER_ARGS) |
| 918 | { |
| 919 | int error = 0; |
| 920 | |
| 921 | if (!arg1) |
| 922 | return (EINVAL); |
| 923 | error = SYSCTL_OUT(req, arg1, sizeof(quad_t)); |
| 924 | |
| 925 | if (error || !req->newptr) |
| 926 | return (error); |
| 927 | |
| 928 | error = SYSCTL_IN(req, arg1, sizeof(quad_t)); |
| 929 | return (error); |
| 930 | } |
| 931 | |
| 932 | /* |
| 933 | * Handle our generic '\0' terminated 'C' string. |
| 934 | * Two cases: |
| 935 | * a variable string: point arg1 at it, arg2 is max length. |
| 936 | * a constant string: point arg1 at it, arg2 is zero. |
| 937 | */ |
| 938 | |
| 939 | int |
| 940 | sysctl_handle_string(SYSCTL_HANDLER_ARGS) |
| 941 | { |
| 942 | int error=0; |
| 943 | |
| 944 | error = SYSCTL_OUT(req, arg1, strlen((char *)arg1)+1); |
| 945 | |
| 946 | if (error || !req->newptr) |
| 947 | return (error); |
| 948 | |
| 949 | if ((req->newlen - req->newidx) >= arg2) { |
| 950 | error = EINVAL; |
| 951 | } else { |
| 952 | arg2 = (req->newlen - req->newidx); |
| 953 | error = SYSCTL_IN(req, arg1, arg2); |
| 954 | ((char *)arg1)[arg2] = '\0'; |
| 955 | } |
| 956 | |
| 957 | return (error); |
| 958 | } |
| 959 | |
| 960 | /* |
| 961 | * Handle any kind of opaque data. |
| 962 | * arg1 points to it, arg2 is the size. |
| 963 | */ |
| 964 | |
| 965 | int |
| 966 | sysctl_handle_opaque(SYSCTL_HANDLER_ARGS) |
| 967 | { |
| 968 | int error; |
| 969 | |
| 970 | error = SYSCTL_OUT(req, arg1, arg2); |
| 971 | |
| 972 | if (error || !req->newptr) |
| 973 | return (error); |
| 974 | |
| 975 | error = SYSCTL_IN(req, arg1, arg2); |
| 976 | |
| 977 | return (error); |
| 978 | } |
| 979 | |
| 980 | /* |
| 981 | * Transfer functions to/from kernel space. |
| 982 | * XXX: rather untested at this point |
| 983 | */ |
| 984 | static int |
| 985 | sysctl_old_kernel(struct sysctl_req *req, const void *p, size_t l) |
| 986 | { |
| 987 | size_t i = 0; |
| 988 | |
| 989 | if (req->oldptr) { |
| 990 | i = l; |
| 991 | if (i > req->oldlen - req->oldidx) |
| 992 | i = req->oldlen - req->oldidx; |
| 993 | if (i > 0) |
| 994 | bcopy(p, (char *)req->oldptr + req->oldidx, i); |
| 995 | } |
| 996 | req->oldidx += l; |
| 997 | if (req->oldptr && i != l) |
| 998 | return (ENOMEM); |
| 999 | return (0); |
| 1000 | } |
| 1001 | |
| 1002 | static int |
| 1003 | sysctl_new_kernel(struct sysctl_req *req, void *p, size_t l) |
| 1004 | { |
| 1005 | |
| 1006 | if (!req->newptr) |
| 1007 | return 0; |
| 1008 | if (req->newlen - req->newidx < l) |
| 1009 | return (EINVAL); |
| 1010 | bcopy((char *)req->newptr + req->newidx, p, l); |
| 1011 | req->newidx += l; |
| 1012 | return (0); |
| 1013 | } |
| 1014 | |
| 1015 | int |
| 1016 | kernel_sysctl(int *name, u_int namelen, void *old, size_t *oldlenp, void *new, size_t newlen, size_t *retval) |
| 1017 | { |
| 1018 | int error = 0; |
| 1019 | struct sysctl_req req; |
| 1020 | |
| 1021 | bzero(&req, sizeof req); |
| 1022 | |
| 1023 | req.td = curthread; |
| 1024 | |
| 1025 | if (oldlenp) { |
| 1026 | req.oldlen = *oldlenp; |
| 1027 | } |
| 1028 | req.validlen = req.oldlen; |
| 1029 | |
| 1030 | if (old) { |
| 1031 | req.oldptr= old; |
| 1032 | } |
| 1033 | |
| 1034 | if (new != NULL) { |
| 1035 | req.newlen = newlen; |
| 1036 | req.newptr = new; |
| 1037 | } |
| 1038 | |
| 1039 | req.oldfunc = sysctl_old_kernel; |
| 1040 | req.newfunc = sysctl_new_kernel; |
| 1041 | #if 0 |
| 1042 | req.lock = REQ_UNWIRED; |
| 1043 | #endif |
| 1044 | |
| 1045 | SYSCTL_XLOCK(); |
| 1046 | error = sysctl_root(0, name, namelen, &req); |
| 1047 | SYSCTL_XUNLOCK(); |
| 1048 | |
| 1049 | #if 0 |
| 1050 | if (req.lock == REQ_WIRED && req.validlen > 0) |
| 1051 | vsunlock(req.oldptr, req.validlen); |
| 1052 | #endif |
| 1053 | |
| 1054 | if (error && error != ENOMEM) |
| 1055 | return (error); |
| 1056 | |
| 1057 | if (retval) { |
| 1058 | if (req.oldptr && req.oldidx > req.validlen) |
| 1059 | *retval = req.validlen; |
| 1060 | else |
| 1061 | *retval = req.oldidx; |
| 1062 | } |
| 1063 | return (error); |
| 1064 | } |
| 1065 | |
| 1066 | int |
| 1067 | kernel_sysctlbyname(char *name, void *old, size_t *oldlenp, |
| 1068 | void *new, size_t newlen, size_t *retval) |
| 1069 | { |
| 1070 | int oid[CTL_MAXNAME]; |
| 1071 | size_t oidlen, plen; |
| 1072 | int error; |
| 1073 | |
| 1074 | oid[0] = 0; /* sysctl internal magic */ |
| 1075 | oid[1] = 3; /* name2oid */ |
| 1076 | oidlen = sizeof(oid); |
| 1077 | |
| 1078 | error = kernel_sysctl(oid, 2, oid, &oidlen, name, strlen(name), &plen); |
| 1079 | if (error) |
| 1080 | return (error); |
| 1081 | |
| 1082 | error = kernel_sysctl(oid, plen / sizeof(int), old, oldlenp, |
| 1083 | new, newlen, retval); |
| 1084 | return (error); |
| 1085 | } |
| 1086 | |
| 1087 | /* |
| 1088 | * Transfer function to/from user space. |
| 1089 | */ |
| 1090 | static int |
| 1091 | sysctl_old_user(struct sysctl_req *req, const void *p, size_t l) |
| 1092 | { |
| 1093 | int error = 0; |
| 1094 | size_t i = 0; |
| 1095 | |
| 1096 | #if 0 |
| 1097 | if (req->lock == 1 && req->oldptr) { |
| 1098 | vslock(req->oldptr, req->oldlen); |
| 1099 | req->lock = 2; |
| 1100 | } |
| 1101 | #endif |
| 1102 | if (req->oldptr) { |
| 1103 | i = l; |
| 1104 | if (i > req->oldlen - req->oldidx) |
| 1105 | i = req->oldlen - req->oldidx; |
| 1106 | if (i > 0) |
| 1107 | error = copyout(p, (char *)req->oldptr + req->oldidx, |
| 1108 | i); |
| 1109 | } |
| 1110 | req->oldidx += l; |
| 1111 | if (error) |
| 1112 | return (error); |
| 1113 | if (req->oldptr && i < l) |
| 1114 | return (ENOMEM); |
| 1115 | return (0); |
| 1116 | } |
| 1117 | |
| 1118 | static int |
| 1119 | sysctl_new_user(struct sysctl_req *req, void *p, size_t l) |
| 1120 | { |
| 1121 | int error; |
| 1122 | |
| 1123 | if (!req->newptr) |
| 1124 | return 0; |
| 1125 | if (req->newlen - req->newidx < l) |
| 1126 | return (EINVAL); |
| 1127 | error = copyin((char *)req->newptr + req->newidx, p, l); |
| 1128 | req->newidx += l; |
| 1129 | return (error); |
| 1130 | } |
| 1131 | |
| 1132 | int |
| 1133 | sysctl_find_oid(int *name, u_int namelen, struct sysctl_oid **noid, |
| 1134 | int *nindx, struct sysctl_req *req) |
| 1135 | { |
| 1136 | struct sysctl_oid_list *lsp; |
| 1137 | struct sysctl_oid *oid; |
| 1138 | int indx; |
| 1139 | |
| 1140 | SYSCTL_ASSERT_XLOCKED(); |
| 1141 | lsp = &sysctl__children; |
| 1142 | indx = 0; |
| 1143 | while (indx < CTL_MAXNAME) { |
| 1144 | SLIST_FOREACH(oid, lsp, oid_link) { |
| 1145 | if (oid->oid_number == name[indx]) |
| 1146 | break; |
| 1147 | } |
| 1148 | if (oid == NULL) |
| 1149 | return (ENOENT); |
| 1150 | |
| 1151 | indx++; |
| 1152 | if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { |
| 1153 | if (oid->oid_handler != NULL || indx == namelen) { |
| 1154 | *noid = oid; |
| 1155 | if (nindx != NULL) |
| 1156 | *nindx = indx; |
| 1157 | KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, |
| 1158 | ("%s found DYING node %p", __func__, oid)); |
| 1159 | return (0); |
| 1160 | } |
| 1161 | lsp = SYSCTL_CHILDREN(oid); |
| 1162 | } else if (indx == namelen) { |
| 1163 | *noid = oid; |
| 1164 | if (nindx != NULL) |
| 1165 | *nindx = indx; |
| 1166 | KASSERT((oid->oid_kind & CTLFLAG_DYING) == 0, |
| 1167 | ("%s found DYING node %p", __func__, oid)); |
| 1168 | return (0); |
| 1169 | } else { |
| 1170 | return (ENOTDIR); |
| 1171 | } |
| 1172 | } |
| 1173 | return (ENOENT); |
| 1174 | } |
| 1175 | |
| 1176 | /* |
| 1177 | * Traverse our tree, and find the right node, execute whatever it points |
| 1178 | * to, and return the resulting error code. |
| 1179 | */ |
| 1180 | |
| 1181 | static int |
| 1182 | sysctl_root(SYSCTL_HANDLER_ARGS) |
| 1183 | { |
| 1184 | struct thread *td = req->td; |
| 1185 | struct proc *p = td ? td->td_proc : NULL; |
| 1186 | struct sysctl_oid *oid; |
| 1187 | int error, indx; |
| 1188 | |
| 1189 | error = sysctl_find_oid(arg1, arg2, &oid, &indx, req); |
| 1190 | if (error) |
| 1191 | return (error); |
| 1192 | |
| 1193 | if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) { |
| 1194 | /* |
| 1195 | * You can't call a sysctl when it's a node, but has |
| 1196 | * no handler. Inform the user that it's a node. |
| 1197 | * The indx may or may not be the same as namelen. |
| 1198 | */ |
| 1199 | if (oid->oid_handler == NULL) |
| 1200 | return (EISDIR); |
| 1201 | } |
| 1202 | |
| 1203 | /* If writing isn't allowed */ |
| 1204 | if (req->newptr && (!(oid->oid_kind & CTLFLAG_WR) || |
| 1205 | ((oid->oid_kind & CTLFLAG_SECURE) && securelevel > 0))) |
| 1206 | return (EPERM); |
| 1207 | |
| 1208 | /* Most likely only root can write */ |
| 1209 | if (!(oid->oid_kind & CTLFLAG_ANYBODY) && req->newptr && p && |
| 1210 | (error = priv_check_cred(td->td_ucred, |
| 1211 | (oid->oid_kind & CTLFLAG_PRISON) ? PRIV_SYSCTL_WRITEJAIL : |
| 1212 | PRIV_SYSCTL_WRITE, 0))) |
| 1213 | return (error); |
| 1214 | |
| 1215 | if (!oid->oid_handler) |
| 1216 | return EINVAL; |
| 1217 | |
| 1218 | if ((oid->oid_kind & CTLTYPE) == CTLTYPE_NODE) |
| 1219 | error = oid->oid_handler(oid, (int *)arg1 + indx, arg2 - indx, |
| 1220 | req); |
| 1221 | else |
| 1222 | error = oid->oid_handler(oid, oid->oid_arg1, oid->oid_arg2, |
| 1223 | req); |
| 1224 | return (error); |
| 1225 | } |
| 1226 | |
| 1227 | int |
| 1228 | sys___sysctl(struct sysctl_args *uap) |
| 1229 | { |
| 1230 | int error, i, name[CTL_MAXNAME]; |
| 1231 | size_t j; |
| 1232 | |
| 1233 | if (uap->namelen > CTL_MAXNAME || uap->namelen < 2) |
| 1234 | return (EINVAL); |
| 1235 | |
| 1236 | error = copyin(uap->name, &name, uap->namelen * sizeof(int)); |
| 1237 | if (error) |
| 1238 | return (error); |
| 1239 | |
| 1240 | error = userland_sysctl(name, uap->namelen, |
| 1241 | uap->old, uap->oldlenp, 0, |
| 1242 | uap->new, uap->newlen, &j); |
| 1243 | if (error && error != ENOMEM) |
| 1244 | return (error); |
| 1245 | if (uap->oldlenp) { |
| 1246 | i = copyout(&j, uap->oldlenp, sizeof(j)); |
| 1247 | if (i) |
| 1248 | return (i); |
| 1249 | } |
| 1250 | return (error); |
| 1251 | } |
| 1252 | |
| 1253 | /* |
| 1254 | * This is used from various compatibility syscalls too. That's why name |
| 1255 | * must be in kernel space. |
| 1256 | */ |
| 1257 | int |
| 1258 | userland_sysctl(int *name, u_int namelen, void *old, |
| 1259 | size_t *oldlenp, int inkernel, void *new, size_t newlen, size_t *retval) |
| 1260 | { |
| 1261 | int error = 0, memlocked; |
| 1262 | struct sysctl_req req; |
| 1263 | |
| 1264 | bzero(&req, sizeof req); |
| 1265 | |
| 1266 | req.td = curthread; |
| 1267 | req.flags = 0; |
| 1268 | |
| 1269 | if (oldlenp) { |
| 1270 | if (inkernel) { |
| 1271 | req.oldlen = *oldlenp; |
| 1272 | } else { |
| 1273 | error = copyin(oldlenp, &req.oldlen, sizeof(*oldlenp)); |
| 1274 | if (error) |
| 1275 | return (error); |
| 1276 | } |
| 1277 | } |
| 1278 | req.validlen = req.oldlen; |
| 1279 | |
| 1280 | if (old) { |
| 1281 | if (!useracc(old, req.oldlen, VM_PROT_WRITE)) |
| 1282 | return (EFAULT); |
| 1283 | req.oldptr= old; |
| 1284 | } |
| 1285 | |
| 1286 | if (new != NULL) { |
| 1287 | if (!useracc(new, newlen, VM_PROT_READ)) |
| 1288 | return (EFAULT); |
| 1289 | req.newlen = newlen; |
| 1290 | req.newptr = new; |
| 1291 | } |
| 1292 | |
| 1293 | req.oldfunc = sysctl_old_user; |
| 1294 | req.newfunc = sysctl_new_user; |
| 1295 | #if 0 |
| 1296 | req.lock = REQ_UNWIRED; |
| 1297 | #endif |
| 1298 | |
| 1299 | #ifdef KTRACE |
| 1300 | if (KTRPOINT(curthread, KTR_SYSCTL)) |
| 1301 | ktrsysctl(name, namelen); |
| 1302 | #endif |
| 1303 | |
| 1304 | if (req.oldlen > PAGE_SIZE) { |
| 1305 | memlocked = 1; |
| 1306 | lockmgr(&sysctlmemlock, LK_EXCLUSIVE); |
| 1307 | } else |
| 1308 | memlocked = 0; |
| 1309 | |
| 1310 | for (;;) { |
| 1311 | req.oldidx = 0; |
| 1312 | req.newidx = 0; |
| 1313 | SYSCTL_XLOCK(); |
| 1314 | error = sysctl_root(0, name, namelen, &req); |
| 1315 | SYSCTL_XUNLOCK(); |
| 1316 | if (error != EAGAIN) |
| 1317 | break; |
| 1318 | lwkt_yield(); |
| 1319 | } |
| 1320 | |
| 1321 | #if 0 |
| 1322 | if (req.lock == REQ_WIRED && req.validlen > 0) |
| 1323 | vsunlock(req.oldptr, req.validlen); |
| 1324 | #endif |
| 1325 | if (memlocked) |
| 1326 | lockmgr(&sysctlmemlock, LK_RELEASE); |
| 1327 | |
| 1328 | if (error && error != ENOMEM) |
| 1329 | return (error); |
| 1330 | |
| 1331 | if (retval) { |
| 1332 | if (req.oldptr && req.oldidx > req.validlen) |
| 1333 | *retval = req.validlen; |
| 1334 | else |
| 1335 | *retval = req.oldidx; |
| 1336 | } |
| 1337 | return (error); |
| 1338 | } |
| 1339 | |
| 1340 | int |
| 1341 | sysctl_int_range(SYSCTL_HANDLER_ARGS, int low, int high) |
| 1342 | { |
| 1343 | int error, value; |
| 1344 | |
| 1345 | value = *(int *)arg1; |
| 1346 | error = sysctl_handle_int(oidp, &value, 0, req); |
| 1347 | if (error || !req->newptr) |
| 1348 | return (error); |
| 1349 | if (value < low || value > high) |
| 1350 | return (EINVAL); |
| 1351 | *(int *)arg1 = value; |
| 1352 | return (0); |
| 1353 | } |
| 1354 | |
| 1355 | /* |
| 1356 | * Drain into a sysctl struct. The user buffer should be wired if a page |
| 1357 | * fault would cause issue. |
| 1358 | */ |
| 1359 | static int |
| 1360 | sbuf_sysctl_drain(void *arg, const char *data, int len) |
| 1361 | { |
| 1362 | struct sysctl_req *req = arg; |
| 1363 | int error; |
| 1364 | |
| 1365 | error = SYSCTL_OUT(req, data, len); |
| 1366 | KASSERT(error >= 0, ("Got unexpected negative value %d", error)); |
| 1367 | return (error == 0 ? len : -error); |
| 1368 | } |
| 1369 | |
| 1370 | struct sbuf * |
| 1371 | sbuf_new_for_sysctl(struct sbuf *s, char *buf, int length, |
| 1372 | struct sysctl_req *req) |
| 1373 | { |
| 1374 | |
| 1375 | s = sbuf_new(s, buf, length, SBUF_FIXEDLEN); |
| 1376 | sbuf_set_drain(s, sbuf_sysctl_drain, req); |
| 1377 | return (s); |
| 1378 | } |