sysctl.c revision 1.28
1/* $NetBSD: sysctl.c,v 1.28 2005/11/29 03:11:59 christos Exp $ */ 2 3/*- 4 * Copyright (c) 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32#include <sys/cdefs.h> 33#if defined(LIBC_SCCS) && !defined(lint) 34#if 0 35static char sccsid[] = "@(#)sysctl.c 8.2 (Berkeley) 1/4/94"; 36#else 37__RCSID("$NetBSD: sysctl.c,v 1.28 2005/11/29 03:11:59 christos Exp $"); 38#endif 39#endif /* LIBC_SCCS and not lint */ 40 41#include "namespace.h" 42#include <sys/param.h> 43#define __COMPAT_SYSCTL 44#include <sys/sysctl.h> 45 46#include <errno.h> 47#include <paths.h> 48#include <stdio.h> 49#include <string.h> 50#include <unistd.h> 51#include "extern.h" 52 53#ifdef __weak_alias 54__weak_alias(sysctl,_sysctl) 55#endif 56 57/* 58 * handles requests off the user subtree 59 */ 60static int user_sysctl(int *, u_int, void *, size_t *, const void *, size_t); 61 62/* 63 * copies out individual nodes taking target version into account 64 */ 65static size_t __cvt_node_out(uint, const struct sysctlnode *, void **, 66 size_t *); 67 68#include <stdlib.h> 69 70int 71sysctl(name, namelen, oldp, oldlenp, newp, newlen) 72 int *name; 73 unsigned int namelen; 74 void *oldp; 75 const void *newp; 76 size_t *oldlenp, newlen; 77{ 78 size_t oldlen, savelen; 79 int error; 80 81 if (name[0] != CTL_USER) 82 return (__sysctl(name, namelen, oldp, oldlenp, 83 __UNCONST(newp), newlen)); 84 85 oldlen = (oldlenp == NULL) ? 0 : *oldlenp; 86 savelen = oldlen; 87 error = user_sysctl(name + 1, namelen - 1, oldp, &oldlen, newp, newlen); 88 89 if (error != 0) { 90 errno = error; 91 return (-1); 92 } 93 94 if (oldlenp != NULL) { 95 *oldlenp = oldlen; 96 if (oldp != NULL && oldlen > savelen) { 97 errno = ENOMEM; 98 return (-1); 99 } 100 } 101 102 return (0); 103} 104 105static int 106user_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 107 int *name; 108 unsigned int namelen; 109 void *oldp; 110 const void *newp; 111 size_t *oldlenp, newlen; 112{ 113#define _INT(s, n, v, d) { \ 114 .sysctl_flags = CTLFLAG_IMMEDIATE|CTLFLAG_PERMANENT| \ 115 CTLTYPE_INT|SYSCTL_VERSION, \ 116 sysc_init_field(_sysctl_size, sizeof(int)), \ 117 .sysctl_name = (s), \ 118 .sysctl_num = (n), \ 119 .sysctl_un = { .scu_idata = (v), }, \ 120 sysc_init_field(_sysctl_desc, (d)), \ 121 } 122 123 /* 124 * the nodes under the "user" node 125 */ 126 static const struct sysctlnode sysctl_usermib[] = { 127#if defined(lint) 128 /* 129 * lint doesn't like my initializers 130 */ 131 0 132#else /* !lint */ 133 { 134 .sysctl_flags = SYSCTL_VERSION|CTLFLAG_PERMANENT| 135 CTLTYPE_STRING, 136 sysc_init_field(_sysctl_size, sizeof(_PATH_STDPATH)), 137 .sysctl_name = "cs_path", 138 .sysctl_num = USER_CS_PATH, 139 /* 140 * XXX these nasty initializers (and the one in 141 * the _INT() macro) can go away once all ports 142 * are using gcc3, and become 143 * 144 * .sysctl_data = _PATH_STDPATH, 145 * .sysctl_desc = NULL, 146 */ 147 .sysctl_un = { .scu_data = { 148 sysc_init_field(_sud_data, 149 __UNCONST(_PATH_STDPATH)), 150 }, }, 151 sysc_init_field(_sysctl_desc, 152 "A value for the PATH environment variable " 153 "that finds all the standard utilities"), 154 }, 155 _INT("bc_base_max", USER_BC_BASE_MAX, BC_BASE_MAX, 156 "The maximum ibase/obase values in the bc(1) utility"), 157 _INT("bc_dim_max", USER_BC_DIM_MAX, BC_DIM_MAX, 158 "The maximum array size in the bc(1) utility"), 159 _INT("bc_scale_max", USER_BC_SCALE_MAX, BC_SCALE_MAX, 160 "The maximum scale value in the bc(1) utility"), 161 _INT("bc_string_max", USER_BC_STRING_MAX, BC_STRING_MAX, 162 "The maximum string length in the bc(1) utility"), 163 _INT("coll_weights_max", USER_COLL_WEIGHTS_MAX, 164 COLL_WEIGHTS_MAX, "The maximum number of weights that can " 165 "be assigned to any entry of the LC_COLLATE order keyword " 166 "in the locale definition file"), 167 _INT("expr_nest_max", USER_EXPR_NEST_MAX, EXPR_NEST_MAX, 168 "The maximum number of expressions that can be nested " 169 "within parenthesis by the expr(1) utility"), 170 _INT("line_max", USER_LINE_MAX, LINE_MAX, "The maximum length " 171 "in bytes of a text-processing utility's input line"), 172 _INT("re_dup_max", USER_RE_DUP_MAX, RE_DUP_MAX, "The maximum " 173 "number of repeated occurrences of a regular expression " 174 "permitted when using interval notation"), 175 _INT("posix2_version", USER_POSIX2_VERSION, _POSIX2_VERSION, 176 "The version of POSIX 1003.2 with which the system " 177 "attempts to comply"), 178#ifdef POSIX2_C_BIND 179 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 1, 180 "Whether the system's C-language development facilities " 181 "support the C-Language Bindings Option"), 182#else 183 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 0, 184 "Whether the system's C-language development facilities " 185 "support the C-Language Bindings Option"), 186#endif 187#ifdef POSIX2_C_DEV 188 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 1, 189 "Whether the system supports the C-Language Development " 190 "Utilities Option"), 191#else 192 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 0, 193 "Whether the system supports the C-Language Development " 194 "Utilities Option"), 195#endif 196#ifdef POSIX2_CHAR_TERM 197 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 1, 198 "Whether the system supports at least one terminal type " 199 "capable of all operations described in POSIX 1003.2"), 200#else 201 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 0, 202 "Whether the system supports at least one terminal type " 203 "capable of all operations described in POSIX 1003.2"), 204#endif 205#ifdef POSIX2_FORT_DEV 206 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 1, 207 "Whether the system supports the FORTRAN Development " 208 "Utilities Option"), 209#else 210 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 0, 211 "Whether the system supports the FORTRAN Development " 212 "Utilities Option"), 213#endif 214#ifdef POSIX2_FORT_RUN 215 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 1, 216 "Whether the system supports the FORTRAN Runtime " 217 "Utilities Option"), 218#else 219 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 0, 220 "Whether the system supports the FORTRAN Runtime " 221 "Utilities Option"), 222#endif 223#ifdef POSIX2_LOCALEDEF 224 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 1, 225 "Whether the system supports the creation of locales"), 226#else 227 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 0, 228 "Whether the system supports the creation of locales"), 229#endif 230#ifdef POSIX2_SW_DEV 231 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 1, 232 "Whether the system supports the Software Development " 233 "Utilities Option"), 234#else 235 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 0, 236 "Whether the system supports the Software Development " 237 "Utilities Option"), 238#endif 239#ifdef POSIX2_UPE 240 _INT("posix2_upe", USER_POSIX2_UPE, 1, 241 "Whether the system supports the User Portability " 242 "Utilities Option"), 243#else 244 _INT("posix2_upe", USER_POSIX2_UPE, 0, 245 "Whether the system supports the User Portability " 246 "Utilities Option"), 247#endif 248 _INT("stream_max", USER_STREAM_MAX, FOPEN_MAX, 249 "The minimum maximum number of streams that a process " 250 "may have open at any one time"), 251 _INT("tzname_max", USER_TZNAME_MAX, NAME_MAX, 252 "The minimum maximum number of types supported for the " 253 "name of a timezone"), 254 _INT("atexit_max", USER_ATEXIT_MAX, -1, 255 "The maximum number of functions that may be registered " 256 "with atexit(3)"), 257#endif /* !lint */ 258 }; 259#undef _INT 260 261 static const int clen = sizeof(sysctl_usermib) / 262 sizeof(sysctl_usermib[0]); 263 264 const struct sysctlnode *node; 265 int ni; 266 size_t l, sz; 267 268 /* 269 * none of these nodes are writable and they're all terminal (for now) 270 */ 271 if (namelen != 1) 272 return (EINVAL); 273 274 l = *oldlenp; 275 if (name[0] == CTL_QUERY) { 276 uint v; 277 node = newp; 278 if (node == NULL) 279 return (EINVAL); 280 else if (SYSCTL_VERS(node->sysctl_flags) == SYSCTL_VERS_1 && 281 newlen == sizeof(struct sysctlnode)) 282 v = SYSCTL_VERS_1; 283 else 284 return (EINVAL); 285 286 sz = 0; 287 for (ni = 0; ni < clen; ni++) 288 sz += __cvt_node_out(v, &sysctl_usermib[ni], &oldp, &l); 289 *oldlenp = sz; 290 return (0); 291 } 292 293 if (name[0] == CTL_DESCRIBE) { 294 /* 295 * XXX make sure this is larger than the largest 296 * "user" description 297 */ 298 char buf[192]; 299 struct sysctldesc *d1 = (void *)&buf[0], *d2 = oldp; 300 size_t d; 301 302 node = newp; 303 if (node != NULL && 304 (SYSCTL_VERS(node->sysctl_flags) < SYSCTL_VERS_1 || 305 newlen != sizeof(struct sysctlnode))) 306 return (EINVAL); 307 308 sz = 0; 309 for (ni = 0; ni < clen; ni++) { 310 memset(&buf[0], 0, sizeof(buf)); 311 if (node != NULL && 312 node->sysctl_num != sysctl_usermib[ni].sysctl_num) 313 continue; 314 d1->descr_num = sysctl_usermib[ni].sysctl_num; 315 d1->descr_ver = sysctl_usermib[ni].sysctl_ver; 316 if (sysctl_usermib[ni].sysctl_desc == NULL) 317 d1->descr_len = 1; 318 else { 319 (void)strlcpy(d1->descr_str, 320 sysctl_usermib[ni].sysctl_desc, 321 sizeof(buf) - sizeof(*d1)); 322 d1->descr_len = strlen(d1->descr_str) + 1; 323 } 324 d = (size_t)__sysc_desc_adv(NULL, d1->descr_len); 325 if (d2 != NULL) 326 memcpy(d2, d1, d); 327 sz += d; 328 if (node != NULL) 329 break; 330 } 331 *oldlenp = sz; 332 if (sz == 0 && node != NULL) 333 return (ENOENT); 334 return (0); 335 336 } 337 338 /* 339 * none of these nodes are writable 340 */ 341 if (newp != NULL || newlen != 0) 342 return (EPERM); 343 344 node = &sysctl_usermib[0]; 345 for (ni = 0; ni < clen; ni++) 346 if (name[0] == node[ni].sysctl_num) 347 break; 348 if (ni == clen) 349 return (EOPNOTSUPP); 350 351 node = &node[ni]; 352 if (node->sysctl_flags & CTLFLAG_IMMEDIATE) { 353 switch (SYSCTL_TYPE(node->sysctl_flags)) { 354 case CTLTYPE_INT: 355 newp = &node->sysctl_idata; 356 break; 357 case CTLTYPE_QUAD: 358 newp = &node->sysctl_qdata; 359 break; 360 default: 361 return (EINVAL); 362 } 363 } 364 else 365 newp = node->sysctl_data; 366 367 l = MIN(l, node->sysctl_size); 368 if (oldp != NULL) 369 memcpy(oldp, newp, l); 370 *oldlenp = node->sysctl_size; 371 372 return (0); 373} 374 375static size_t 376__cvt_node_out(uint v, const struct sysctlnode *n, void **o, size_t *l) 377{ 378 const void *src = n; 379 size_t sz; 380 381 switch (v) { 382#if (SYSCTL_VERSION != SYSCTL_VERS_1) 383#error __cvt_node_out: no support for SYSCTL_VERSION 384#endif /* (SYSCTL_VERSION != SYSCTL_VERS_1) */ 385 386 case SYSCTL_VERSION: 387 sz = sizeof(struct sysctlnode); 388 break; 389 390 default: 391 sz = 0; 392 break; 393 } 394 395 if (sz > 0 && *o != NULL && *l >= sz) { 396 memcpy(*o, src, sz); 397 *o = sz + (caddr_t)*o; 398 *l -= sz; 399 } 400 401 return(sz); 402} 403