1 /* $NetBSD: sysctl.c,v 1.32 2012/03/20 16:36:05 matt 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 1.32 2012/03/20 16:36:05 matt 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 <assert.h> 47 #include <errno.h> 48 #include <paths.h> 49 #include <stdio.h> 50 #include <string.h> 51 #include <unistd.h> 52 #include "extern.h" 53 54 #ifdef __weak_alias 55 __weak_alias(sysctl,_sysctl) 56 #endif 57 58 /* 59 * handles requests off the user subtree 60 */ 61 static int user_sysctl(const int *, u_int, void *, size_t *, 62 const void *, size_t); 63 64 /* 65 * copies out individual nodes taking target version into account 66 */ 67 static size_t __cvt_node_out(uint, const struct sysctlnode *, void **, 68 size_t *); 69 70 #include <stdlib.h> 71 72 int 73 sysctl(const int *name, unsigned int namelen, 74 void *oldp, size_t *oldlenp, 75 const void *newp, size_t newlen) 76 { 77 size_t oldlen, savelen; 78 int error; 79 80 if (name[0] != CTL_USER) 81 return (__sysctl(name, namelen, oldp, oldlenp, 82 newp, newlen)); 83 84 oldlen = (oldlenp == NULL) ? 0 : *oldlenp; 85 savelen = oldlen; 86 error = user_sysctl(name + 1, namelen - 1, oldp, &oldlen, newp, newlen); 87 88 if (error != 0) { 89 errno = error; 90 return (-1); 91 } 92 93 if (oldlenp != NULL) { 94 *oldlenp = oldlen; 95 if (oldp != NULL && oldlen > savelen) { 96 errno = ENOMEM; 97 return (-1); 98 } 99 } 100 101 return (0); 102 } 103 104 static int 105 user_sysctl(const int *name, unsigned int namelen, 106 void *oldp, size_t *oldlenp, 107 const void *newp, size_t newlen) 108 { 109 #define _INT(s, n, v, d) { \ 110 .sysctl_flags = CTLFLAG_IMMEDIATE|CTLFLAG_PERMANENT| \ 111 CTLTYPE_INT|SYSCTL_VERSION, \ 112 sysc_init_field(_sysctl_size, sizeof(int)), \ 113 .sysctl_name = (s), \ 114 .sysctl_num = (n), \ 115 .sysctl_un = { .scu_idata = (v), }, \ 116 sysc_init_field(_sysctl_desc, (d)), \ 117 } 118 119 /* 120 * the nodes under the "user" node 121 */ 122 static const struct sysctlnode sysctl_usermib[] = { 123 #if defined(lint) 124 /* 125 * lint doesn't like my initializers 126 */ 127 0 128 #else /* !lint */ 129 { 130 .sysctl_flags = SYSCTL_VERSION|CTLFLAG_PERMANENT| 131 CTLTYPE_STRING, 132 sysc_init_field(_sysctl_size, sizeof(_PATH_STDPATH)), 133 .sysctl_name = "cs_path", 134 .sysctl_num = USER_CS_PATH, 135 /* 136 * XXX these nasty initializers (and the one in 137 * the _INT() macro) can go away once all ports 138 * are using gcc3, and become 139 * 140 * .sysctl_data = _PATH_STDPATH, 141 * .sysctl_desc = NULL, 142 */ 143 .sysctl_un = { .scu_data = { 144 sysc_init_field(_sud_data, 145 __UNCONST(_PATH_STDPATH)), 146 }, }, 147 sysc_init_field(_sysctl_desc, 148 "A value for the PATH environment variable " 149 "that finds all the standard utilities"), 150 }, 151 _INT("bc_base_max", USER_BC_BASE_MAX, BC_BASE_MAX, 152 "The maximum ibase/obase values in the bc(1) utility"), 153 _INT("bc_dim_max", USER_BC_DIM_MAX, BC_DIM_MAX, 154 "The maximum array size in the bc(1) utility"), 155 _INT("bc_scale_max", USER_BC_SCALE_MAX, BC_SCALE_MAX, 156 "The maximum scale value in the bc(1) utility"), 157 _INT("bc_string_max", USER_BC_STRING_MAX, BC_STRING_MAX, 158 "The maximum string length in the bc(1) utility"), 159 _INT("coll_weights_max", USER_COLL_WEIGHTS_MAX, 160 COLL_WEIGHTS_MAX, "The maximum number of weights that can " 161 "be assigned to any entry of the LC_COLLATE order keyword " 162 "in the locale definition file"), 163 _INT("expr_nest_max", USER_EXPR_NEST_MAX, EXPR_NEST_MAX, 164 "The maximum number of expressions that can be nested " 165 "within parenthesis by the expr(1) utility"), 166 _INT("line_max", USER_LINE_MAX, LINE_MAX, "The maximum length " 167 "in bytes of a text-processing utility's input line"), 168 _INT("re_dup_max", USER_RE_DUP_MAX, RE_DUP_MAX, "The maximum " 169 "number of repeated occurrences of a regular expression " 170 "permitted when using interval notation"), 171 _INT("posix2_version", USER_POSIX2_VERSION, _POSIX2_VERSION, 172 "The version of POSIX 1003.2 with which the system " 173 "attempts to comply"), 174 #ifdef _POSIX2_C_BIND 175 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 1, 176 "Whether the system's C-language development facilities " 177 "support the C-Language Bindings Option"), 178 #else 179 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 0, 180 "Whether the system's C-language development facilities " 181 "support the C-Language Bindings Option"), 182 #endif 183 #ifdef POSIX2_C_DEV 184 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 1, 185 "Whether the system supports the C-Language Development " 186 "Utilities Option"), 187 #else 188 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 0, 189 "Whether the system supports the C-Language Development " 190 "Utilities Option"), 191 #endif 192 #ifdef POSIX2_CHAR_TERM 193 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 1, 194 "Whether the system supports at least one terminal type " 195 "capable of all operations described in POSIX 1003.2"), 196 #else 197 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 0, 198 "Whether the system supports at least one terminal type " 199 "capable of all operations described in POSIX 1003.2"), 200 #endif 201 #ifdef POSIX2_FORT_DEV 202 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 1, 203 "Whether the system supports the FORTRAN Development " 204 "Utilities Option"), 205 #else 206 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 0, 207 "Whether the system supports the FORTRAN Development " 208 "Utilities Option"), 209 #endif 210 #ifdef POSIX2_FORT_RUN 211 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 1, 212 "Whether the system supports the FORTRAN Runtime " 213 "Utilities Option"), 214 #else 215 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 0, 216 "Whether the system supports the FORTRAN Runtime " 217 "Utilities Option"), 218 #endif 219 #ifdef POSIX2_LOCALEDEF 220 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 1, 221 "Whether the system supports the creation of locales"), 222 #else 223 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 0, 224 "Whether the system supports the creation of locales"), 225 #endif 226 #ifdef POSIX2_SW_DEV 227 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 1, 228 "Whether the system supports the Software Development " 229 "Utilities Option"), 230 #else 231 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 0, 232 "Whether the system supports the Software Development " 233 "Utilities Option"), 234 #endif 235 #ifdef POSIX2_UPE 236 _INT("posix2_upe", USER_POSIX2_UPE, 1, 237 "Whether the system supports the User Portability " 238 "Utilities Option"), 239 #else 240 _INT("posix2_upe", USER_POSIX2_UPE, 0, 241 "Whether the system supports the User Portability " 242 "Utilities Option"), 243 #endif 244 _INT("stream_max", USER_STREAM_MAX, FOPEN_MAX, 245 "The minimum maximum number of streams that a process " 246 "may have open at any one time"), 247 _INT("tzname_max", USER_TZNAME_MAX, NAME_MAX, 248 "The minimum maximum number of types supported for the " 249 "name of a timezone"), 250 _INT("atexit_max", USER_ATEXIT_MAX, -1, 251 "The maximum number of functions that may be registered " 252 "with atexit(3)"), 253 #endif /* !lint */ 254 }; 255 #undef _INT 256 257 static const int clen = sizeof(sysctl_usermib) / 258 sizeof(sysctl_usermib[0]); 259 260 const struct sysctlnode *node; 261 int ni; 262 size_t l, sz; 263 264 /* 265 * none of these nodes are writable and they're all terminal (for now) 266 */ 267 if (namelen != 1) 268 return (EINVAL); 269 270 l = *oldlenp; 271 if (name[0] == CTL_QUERY) { 272 uint v; 273 node = newp; 274 if (node == NULL) 275 return (EINVAL); 276 else if (SYSCTL_VERS(node->sysctl_flags) == SYSCTL_VERS_1 && 277 newlen == sizeof(struct sysctlnode)) 278 v = SYSCTL_VERS_1; 279 else 280 return (EINVAL); 281 282 sz = 0; 283 for (ni = 0; ni < clen; ni++) 284 sz += __cvt_node_out(v, &sysctl_usermib[ni], &oldp, &l); 285 *oldlenp = sz; 286 return (0); 287 } 288 289 if (name[0] == CTL_DESCRIBE) { 290 /* 291 * XXX make sure this is larger than the largest 292 * "user" description 293 */ 294 char buf[192]; 295 struct sysctldesc *d1 = (void *)&buf[0], *d2 = oldp; 296 size_t d; 297 298 node = newp; 299 if (node != NULL && 300 (SYSCTL_VERS(node->sysctl_flags) < SYSCTL_VERS_1 || 301 newlen != sizeof(struct sysctlnode))) 302 return (EINVAL); 303 304 sz = 0; 305 for (ni = 0; ni < clen; ni++) { 306 memset(&buf[0], 0, sizeof(buf)); 307 if (node != NULL && 308 node->sysctl_num != sysctl_usermib[ni].sysctl_num) 309 continue; 310 d1->descr_num = sysctl_usermib[ni].sysctl_num; 311 d1->descr_ver = sysctl_usermib[ni].sysctl_ver; 312 if (sysctl_usermib[ni].sysctl_desc == NULL) 313 d1->descr_len = 1; 314 else { 315 size_t dlen; 316 (void)strlcpy(d1->descr_str, 317 sysctl_usermib[ni].sysctl_desc, 318 sizeof(buf) - sizeof(*d1)); 319 dlen = strlen(d1->descr_str) + 1; 320 _DIAGASSERT(__type_fit(uint32_t, dlen)); 321 d1->descr_len = (uint32_t)dlen; 322 } 323 d = (size_t)__sysc_desc_adv(NULL, d1->descr_len); 324 if (d2 != NULL) 325 memcpy(d2, d1, d); 326 sz += d; 327 if (node != NULL) 328 break; 329 } 330 *oldlenp = sz; 331 if (sz == 0 && node != NULL) 332 return (ENOENT); 333 return (0); 334 335 } 336 337 /* 338 * none of these nodes are writable 339 */ 340 if (newp != NULL || newlen != 0) 341 return (EPERM); 342 343 node = &sysctl_usermib[0]; 344 for (ni = 0; ni < clen; ni++) 345 if (name[0] == node[ni].sysctl_num) 346 break; 347 if (ni == clen) 348 return (EOPNOTSUPP); 349 350 node = &node[ni]; 351 if (node->sysctl_flags & CTLFLAG_IMMEDIATE) { 352 switch (SYSCTL_TYPE(node->sysctl_flags)) { 353 case CTLTYPE_INT: 354 newp = &node->sysctl_idata; 355 break; 356 case CTLTYPE_QUAD: 357 newp = &node->sysctl_qdata; 358 break; 359 default: 360 return (EINVAL); 361 } 362 } 363 else 364 newp = node->sysctl_data; 365 366 l = MIN(l, node->sysctl_size); 367 if (oldp != NULL) 368 memcpy(oldp, newp, l); 369 *oldlenp = node->sysctl_size; 370 371 return (0); 372 } 373 374 static size_t 375 __cvt_node_out(uint v, const struct sysctlnode *n, void **o, size_t *l) 376 { 377 const void *src = n; 378 size_t sz; 379 380 switch (v) { 381 #if (SYSCTL_VERSION != SYSCTL_VERS_1) 382 #error __cvt_node_out: no support for SYSCTL_VERSION 383 #endif /* (SYSCTL_VERSION != SYSCTL_VERS_1) */ 384 385 case SYSCTL_VERSION: 386 sz = sizeof(struct sysctlnode); 387 break; 388 389 default: 390 sz = 0; 391 break; 392 } 393 394 if (sz > 0 && *o != NULL && *l >= sz) { 395 memcpy(*o, src, sz); 396 *o = sz + (caddr_t)*o; 397 *l -= sz; 398 } 399 400 return(sz); 401 } 402