1 /* $NetBSD: sysctl.c,v 1.30 2008/08/27 08:56:49 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 35 static char sccsid[] = "@(#)sysctl.c 8.2 (Berkeley) 1/4/94"; 36 #else 37 __RCSID("$NetBSD: sysctl.c,v 1.30 2008/08/27 08:56:49 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 */ 60 static int user_sysctl(const int *, u_int, void *, size_t *, 61 const void *, size_t); 62 63 /* 64 * copies out individual nodes taking target version into account 65 */ 66 static size_t __cvt_node_out(uint, const struct sysctlnode *, void **, 67 size_t *); 68 69 #include <stdlib.h> 70 71 int 72 sysctl(name, namelen, oldp, oldlenp, newp, newlen) 73 const int *name; 74 unsigned int namelen; 75 void *oldp; 76 const void *newp; 77 size_t *oldlenp, newlen; 78 { 79 size_t oldlen, savelen; 80 int error; 81 82 if (name[0] != CTL_USER) 83 return (__sysctl(name, namelen, oldp, oldlenp, 84 newp, newlen)); 85 86 oldlen = (oldlenp == NULL) ? 0 : *oldlenp; 87 savelen = oldlen; 88 error = user_sysctl(name + 1, namelen - 1, oldp, &oldlen, newp, newlen); 89 90 if (error != 0) { 91 errno = error; 92 return (-1); 93 } 94 95 if (oldlenp != NULL) { 96 *oldlenp = oldlen; 97 if (oldp != NULL && oldlen > savelen) { 98 errno = ENOMEM; 99 return (-1); 100 } 101 } 102 103 return (0); 104 } 105 106 static int 107 user_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 108 const int *name; 109 unsigned int namelen; 110 void *oldp; 111 const void *newp; 112 size_t *oldlenp, newlen; 113 { 114 #define _INT(s, n, v, d) { \ 115 .sysctl_flags = CTLFLAG_IMMEDIATE|CTLFLAG_PERMANENT| \ 116 CTLTYPE_INT|SYSCTL_VERSION, \ 117 sysc_init_field(_sysctl_size, sizeof(int)), \ 118 .sysctl_name = (s), \ 119 .sysctl_num = (n), \ 120 .sysctl_un = { .scu_idata = (v), }, \ 121 sysc_init_field(_sysctl_desc, (d)), \ 122 } 123 124 /* 125 * the nodes under the "user" node 126 */ 127 static const struct sysctlnode sysctl_usermib[] = { 128 #if defined(lint) 129 /* 130 * lint doesn't like my initializers 131 */ 132 0 133 #else /* !lint */ 134 { 135 .sysctl_flags = SYSCTL_VERSION|CTLFLAG_PERMANENT| 136 CTLTYPE_STRING, 137 sysc_init_field(_sysctl_size, sizeof(_PATH_STDPATH)), 138 .sysctl_name = "cs_path", 139 .sysctl_num = USER_CS_PATH, 140 /* 141 * XXX these nasty initializers (and the one in 142 * the _INT() macro) can go away once all ports 143 * are using gcc3, and become 144 * 145 * .sysctl_data = _PATH_STDPATH, 146 * .sysctl_desc = NULL, 147 */ 148 .sysctl_un = { .scu_data = { 149 sysc_init_field(_sud_data, 150 __UNCONST(_PATH_STDPATH)), 151 }, }, 152 sysc_init_field(_sysctl_desc, 153 "A value for the PATH environment variable " 154 "that finds all the standard utilities"), 155 }, 156 _INT("bc_base_max", USER_BC_BASE_MAX, BC_BASE_MAX, 157 "The maximum ibase/obase values in the bc(1) utility"), 158 _INT("bc_dim_max", USER_BC_DIM_MAX, BC_DIM_MAX, 159 "The maximum array size in the bc(1) utility"), 160 _INT("bc_scale_max", USER_BC_SCALE_MAX, BC_SCALE_MAX, 161 "The maximum scale value in the bc(1) utility"), 162 _INT("bc_string_max", USER_BC_STRING_MAX, BC_STRING_MAX, 163 "The maximum string length in the bc(1) utility"), 164 _INT("coll_weights_max", USER_COLL_WEIGHTS_MAX, 165 COLL_WEIGHTS_MAX, "The maximum number of weights that can " 166 "be assigned to any entry of the LC_COLLATE order keyword " 167 "in the locale definition file"), 168 _INT("expr_nest_max", USER_EXPR_NEST_MAX, EXPR_NEST_MAX, 169 "The maximum number of expressions that can be nested " 170 "within parenthesis by the expr(1) utility"), 171 _INT("line_max", USER_LINE_MAX, LINE_MAX, "The maximum length " 172 "in bytes of a text-processing utility's input line"), 173 _INT("re_dup_max", USER_RE_DUP_MAX, RE_DUP_MAX, "The maximum " 174 "number of repeated occurrences of a regular expression " 175 "permitted when using interval notation"), 176 _INT("posix2_version", USER_POSIX2_VERSION, _POSIX2_VERSION, 177 "The version of POSIX 1003.2 with which the system " 178 "attempts to comply"), 179 #ifdef _POSIX2_C_BIND 180 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 1, 181 "Whether the system's C-language development facilities " 182 "support the C-Language Bindings Option"), 183 #else 184 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 0, 185 "Whether the system's C-language development facilities " 186 "support the C-Language Bindings Option"), 187 #endif 188 #ifdef POSIX2_C_DEV 189 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 1, 190 "Whether the system supports the C-Language Development " 191 "Utilities Option"), 192 #else 193 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 0, 194 "Whether the system supports the C-Language Development " 195 "Utilities Option"), 196 #endif 197 #ifdef POSIX2_CHAR_TERM 198 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 1, 199 "Whether the system supports at least one terminal type " 200 "capable of all operations described in POSIX 1003.2"), 201 #else 202 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 0, 203 "Whether the system supports at least one terminal type " 204 "capable of all operations described in POSIX 1003.2"), 205 #endif 206 #ifdef POSIX2_FORT_DEV 207 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 1, 208 "Whether the system supports the FORTRAN Development " 209 "Utilities Option"), 210 #else 211 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 0, 212 "Whether the system supports the FORTRAN Development " 213 "Utilities Option"), 214 #endif 215 #ifdef POSIX2_FORT_RUN 216 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 1, 217 "Whether the system supports the FORTRAN Runtime " 218 "Utilities Option"), 219 #else 220 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 0, 221 "Whether the system supports the FORTRAN Runtime " 222 "Utilities Option"), 223 #endif 224 #ifdef POSIX2_LOCALEDEF 225 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 1, 226 "Whether the system supports the creation of locales"), 227 #else 228 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 0, 229 "Whether the system supports the creation of locales"), 230 #endif 231 #ifdef POSIX2_SW_DEV 232 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 1, 233 "Whether the system supports the Software Development " 234 "Utilities Option"), 235 #else 236 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 0, 237 "Whether the system supports the Software Development " 238 "Utilities Option"), 239 #endif 240 #ifdef POSIX2_UPE 241 _INT("posix2_upe", USER_POSIX2_UPE, 1, 242 "Whether the system supports the User Portability " 243 "Utilities Option"), 244 #else 245 _INT("posix2_upe", USER_POSIX2_UPE, 0, 246 "Whether the system supports the User Portability " 247 "Utilities Option"), 248 #endif 249 _INT("stream_max", USER_STREAM_MAX, FOPEN_MAX, 250 "The minimum maximum number of streams that a process " 251 "may have open at any one time"), 252 _INT("tzname_max", USER_TZNAME_MAX, NAME_MAX, 253 "The minimum maximum number of types supported for the " 254 "name of a timezone"), 255 _INT("atexit_max", USER_ATEXIT_MAX, -1, 256 "The maximum number of functions that may be registered " 257 "with atexit(3)"), 258 #endif /* !lint */ 259 }; 260 #undef _INT 261 262 static const int clen = sizeof(sysctl_usermib) / 263 sizeof(sysctl_usermib[0]); 264 265 const struct sysctlnode *node; 266 int ni; 267 size_t l, sz; 268 269 /* 270 * none of these nodes are writable and they're all terminal (for now) 271 */ 272 if (namelen != 1) 273 return (EINVAL); 274 275 l = *oldlenp; 276 if (name[0] == CTL_QUERY) { 277 uint v; 278 node = newp; 279 if (node == NULL) 280 return (EINVAL); 281 else if (SYSCTL_VERS(node->sysctl_flags) == SYSCTL_VERS_1 && 282 newlen == sizeof(struct sysctlnode)) 283 v = SYSCTL_VERS_1; 284 else 285 return (EINVAL); 286 287 sz = 0; 288 for (ni = 0; ni < clen; ni++) 289 sz += __cvt_node_out(v, &sysctl_usermib[ni], &oldp, &l); 290 *oldlenp = sz; 291 return (0); 292 } 293 294 if (name[0] == CTL_DESCRIBE) { 295 /* 296 * XXX make sure this is larger than the largest 297 * "user" description 298 */ 299 char buf[192]; 300 struct sysctldesc *d1 = (void *)&buf[0], *d2 = oldp; 301 size_t d; 302 303 node = newp; 304 if (node != NULL && 305 (SYSCTL_VERS(node->sysctl_flags) < SYSCTL_VERS_1 || 306 newlen != sizeof(struct sysctlnode))) 307 return (EINVAL); 308 309 sz = 0; 310 for (ni = 0; ni < clen; ni++) { 311 memset(&buf[0], 0, sizeof(buf)); 312 if (node != NULL && 313 node->sysctl_num != sysctl_usermib[ni].sysctl_num) 314 continue; 315 d1->descr_num = sysctl_usermib[ni].sysctl_num; 316 d1->descr_ver = sysctl_usermib[ni].sysctl_ver; 317 if (sysctl_usermib[ni].sysctl_desc == NULL) 318 d1->descr_len = 1; 319 else { 320 (void)strlcpy(d1->descr_str, 321 sysctl_usermib[ni].sysctl_desc, 322 sizeof(buf) - sizeof(*d1)); 323 d1->descr_len = strlen(d1->descr_str) + 1; 324 } 325 d = (size_t)__sysc_desc_adv(NULL, d1->descr_len); 326 if (d2 != NULL) 327 memcpy(d2, d1, d); 328 sz += d; 329 if (node != NULL) 330 break; 331 } 332 *oldlenp = sz; 333 if (sz == 0 && node != NULL) 334 return (ENOENT); 335 return (0); 336 337 } 338 339 /* 340 * none of these nodes are writable 341 */ 342 if (newp != NULL || newlen != 0) 343 return (EPERM); 344 345 node = &sysctl_usermib[0]; 346 for (ni = 0; ni < clen; ni++) 347 if (name[0] == node[ni].sysctl_num) 348 break; 349 if (ni == clen) 350 return (EOPNOTSUPP); 351 352 node = &node[ni]; 353 if (node->sysctl_flags & CTLFLAG_IMMEDIATE) { 354 switch (SYSCTL_TYPE(node->sysctl_flags)) { 355 case CTLTYPE_INT: 356 newp = &node->sysctl_idata; 357 break; 358 case CTLTYPE_QUAD: 359 newp = &node->sysctl_qdata; 360 break; 361 default: 362 return (EINVAL); 363 } 364 } 365 else 366 newp = node->sysctl_data; 367 368 l = MIN(l, node->sysctl_size); 369 if (oldp != NULL) 370 memcpy(oldp, newp, l); 371 *oldlenp = node->sysctl_size; 372 373 return (0); 374 } 375 376 static size_t 377 __cvt_node_out(uint v, const struct sysctlnode *n, void **o, size_t *l) 378 { 379 const void *src = n; 380 size_t sz; 381 382 switch (v) { 383 #if (SYSCTL_VERSION != SYSCTL_VERS_1) 384 #error __cvt_node_out: no support for SYSCTL_VERSION 385 #endif /* (SYSCTL_VERSION != SYSCTL_VERS_1) */ 386 387 case SYSCTL_VERSION: 388 sz = sizeof(struct sysctlnode); 389 break; 390 391 default: 392 sz = 0; 393 break; 394 } 395 396 if (sz > 0 && *o != NULL && *l >= sz) { 397 memcpy(*o, src, sz); 398 *o = sz + (caddr_t)*o; 399 *l -= sz; 400 } 401 402 return(sz); 403 } 404