1 /* $NetBSD: sysctl.c,v 1.39 2025/09/27 21:00:41 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 1.39 2025/09/27 21:00:41 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 <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 #ifndef SMALL 110 #define X(a) a 111 #else 112 #define X(a) "" 113 #endif 114 #define _INT(s, n, v, d) { \ 115 .sysctl_flags = CTLFLAG_IMMEDIATE|CTLFLAG_PERMANENT| \ 116 CTLTYPE_INT|SYSCTL_VERSION, \ 117 .sysctl_size = sizeof(int), \ 118 .sysctl_name = (s), \ 119 .sysctl_num = (n), \ 120 .sysctl_un.scu_idata = (v), \ 121 .sysctl_desc = X(d), \ 122 } 123 124 /* 125 * the nodes under the "user" node 126 */ 127 static const struct sysctlnode sysctl_usermib[] = { 128 { 129 .sysctl_flags = SYSCTL_VERSION|CTLFLAG_PERMANENT| 130 CTLTYPE_STRING, 131 .sysctl_size = sizeof(_PATH_STDPATH), 132 .sysctl_name = "cs_path", 133 .sysctl_num = USER_CS_PATH, 134 .sysctl_data = __UNCONST(_PATH_STDPATH), 135 .sysctl_desc = __UNCONST( 136 "A value for the PATH environment variable " 137 "that finds all the standard utilities"), 138 }, 139 _INT("bc_base_max", USER_BC_BASE_MAX, BC_BASE_MAX, 140 "The maximum ibase/obase values in the bc(1) utility"), 141 _INT("bc_dim_max", USER_BC_DIM_MAX, BC_DIM_MAX, 142 "The maximum array size in the bc(1) utility"), 143 _INT("bc_scale_max", USER_BC_SCALE_MAX, BC_SCALE_MAX, 144 "The maximum scale value in the bc(1) utility"), 145 _INT("bc_string_max", USER_BC_STRING_MAX, BC_STRING_MAX, 146 "The maximum string length in the bc(1) utility"), 147 _INT("coll_weights_max", USER_COLL_WEIGHTS_MAX, 148 COLL_WEIGHTS_MAX, "The maximum number of weights that can " 149 "be assigned to any entry of the LC_COLLATE order keyword " 150 "in the locale definition file"), 151 _INT("expr_nest_max", USER_EXPR_NEST_MAX, EXPR_NEST_MAX, 152 "The maximum number of expressions that can be nested " 153 "within parenthesis by the expr(1) utility"), 154 _INT("line_max", USER_LINE_MAX, LINE_MAX, "The maximum length " 155 "in bytes of a text-processing utility's input line"), 156 _INT("re_dup_max", USER_RE_DUP_MAX, RE_DUP_MAX, "The maximum " 157 "number of repeated occurrences of a regular expression " 158 "permitted when using interval notation"), 159 _INT("posix2_version", USER_POSIX2_VERSION, _POSIX2_VERSION, 160 "The version of POSIX 1003.2 with which the system " 161 "attempts to comply"), 162 #ifdef _POSIX2_C_BIND 163 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 1, 164 "Whether the system's C-language development facilities " 165 "support the C-Language Bindings Option"), 166 #else 167 _INT("posix2_c_bind", USER_POSIX2_C_BIND, 0, 168 "Whether the system's C-language development facilities " 169 "support the C-Language Bindings Option"), 170 #endif 171 #ifdef POSIX2_C_DEV 172 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 1, 173 "Whether the system supports the C-Language Development " 174 "Utilities Option"), 175 #else 176 _INT("posix2_c_dev", USER_POSIX2_C_DEV, 0, 177 "Whether the system supports the C-Language Development " 178 "Utilities Option"), 179 #endif 180 #ifdef POSIX2_CHAR_TERM 181 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 1, 182 "Whether the system supports at least one terminal type " 183 "capable of all operations described in POSIX 1003.2"), 184 #else 185 _INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 0, 186 "Whether the system supports at least one terminal type " 187 "capable of all operations described in POSIX 1003.2"), 188 #endif 189 #ifdef POSIX2_FORT_DEV 190 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 1, 191 "Whether the system supports the FORTRAN Development " 192 "Utilities Option"), 193 #else 194 _INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 0, 195 "Whether the system supports the FORTRAN Development " 196 "Utilities Option"), 197 #endif 198 #ifdef POSIX2_FORT_RUN 199 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 1, 200 "Whether the system supports the FORTRAN Runtime " 201 "Utilities Option"), 202 #else 203 _INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 0, 204 "Whether the system supports the FORTRAN Runtime " 205 "Utilities Option"), 206 #endif 207 #ifdef POSIX2_LOCALEDEF 208 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 1, 209 "Whether the system supports the creation of locales"), 210 #else 211 _INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 0, 212 "Whether the system supports the creation of locales"), 213 #endif 214 #ifdef POSIX2_SW_DEV 215 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 1, 216 "Whether the system supports the Software Development " 217 "Utilities Option"), 218 #else 219 _INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 0, 220 "Whether the system supports the Software Development " 221 "Utilities Option"), 222 #endif 223 #ifdef POSIX2_UPE 224 _INT("posix2_upe", USER_POSIX2_UPE, 1, 225 "Whether the system supports the User Portability " 226 "Utilities Option"), 227 #else 228 _INT("posix2_upe", USER_POSIX2_UPE, 0, 229 "Whether the system supports the User Portability " 230 "Utilities Option"), 231 #endif 232 _INT("stream_max", USER_STREAM_MAX, FOPEN_MAX, 233 "The minimum maximum number of streams that a process " 234 "may have open at any one time"), 235 _INT("tzname_max", USER_TZNAME_MAX, NAME_MAX, 236 "The minimum maximum number of types supported for the " 237 "name of a timezone"), 238 _INT("atexit_max", USER_ATEXIT_MAX, -1, 239 "The maximum number of functions that may be registered " 240 "with atexit(3)"), 241 }; 242 #undef _INT 243 244 static const int clen = sizeof(sysctl_usermib) / 245 sizeof(sysctl_usermib[0]); 246 247 const struct sysctlnode *node; 248 int ni; 249 size_t l, sz; 250 251 /* 252 * none of these nodes are writable and they're all terminal (for now) 253 */ 254 if (namelen != 1) 255 return (EINVAL); 256 257 l = *oldlenp; 258 if (name[0] == CTL_QUERY) { 259 uint v; 260 node = newp; 261 if (node == NULL) 262 return (EINVAL); 263 else if (SYSCTL_VERS(node->sysctl_flags) == SYSCTL_VERS_1 && 264 newlen == sizeof(struct sysctlnode)) 265 v = SYSCTL_VERS_1; 266 else 267 return (EINVAL); 268 269 sz = 0; 270 for (ni = 0; ni < clen; ni++) 271 sz += __cvt_node_out(v, &sysctl_usermib[ni], &oldp, &l); 272 *oldlenp = sz; 273 return (0); 274 } 275 276 if (name[0] == CTL_DESCRIBE) { 277 /* 278 * XXX make sure this is larger than the largest 279 * "user" description 280 */ 281 char buf[192]; 282 struct sysctldesc *d1 = (void *)&buf[0], *d2 = oldp; 283 size_t d; 284 285 node = newp; 286 if (node != NULL && 287 (SYSCTL_VERS(node->sysctl_flags) < SYSCTL_VERS_1 || 288 newlen != sizeof(struct sysctlnode))) 289 return (EINVAL); 290 291 sz = 0; 292 for (ni = 0; ni < clen; ni++) { 293 memset(&buf[0], 0, sizeof(buf)); 294 if (node != NULL && 295 node->sysctl_num != sysctl_usermib[ni].sysctl_num) 296 continue; 297 d1->descr_num = sysctl_usermib[ni].sysctl_num; 298 d1->descr_ver = sysctl_usermib[ni].sysctl_ver; 299 if (sysctl_usermib[ni].sysctl_desc == NULL) 300 d1->descr_len = 1; 301 else { 302 size_t dlen; 303 (void)strlcpy(d1->descr_str, 304 sysctl_usermib[ni].sysctl_desc, 305 sizeof(buf) - sizeof(*d1)); 306 dlen = strlen(d1->descr_str) + 1; 307 _DIAGASSERT(__type_fit(uint32_t, dlen)); 308 d1->descr_len = (uint32_t)dlen; 309 } 310 d = (size_t)__sysc_desc_len(d1->descr_len); 311 if (d2 != NULL) 312 memcpy(d2, d1, d); 313 sz += d; 314 d2 = (void *)((char *)(void *)d2 + d); 315 if (node != NULL) 316 break; 317 } 318 *oldlenp = sz; 319 if (sz == 0 && node != NULL) 320 return (ENOENT); 321 return (0); 322 323 } 324 325 /* 326 * none of these nodes are writable 327 */ 328 if (newp != NULL || newlen != 0) 329 return (EPERM); 330 331 node = &sysctl_usermib[0]; 332 for (ni = 0; ni < clen; ni++) 333 if (name[0] == node[ni].sysctl_num) 334 break; 335 if (ni == clen) 336 return (EOPNOTSUPP); 337 338 node = &node[ni]; 339 if (node->sysctl_flags & CTLFLAG_IMMEDIATE) { 340 switch (SYSCTL_TYPE(node->sysctl_flags)) { 341 case CTLTYPE_INT: 342 newp = &node->sysctl_idata; 343 break; 344 case CTLTYPE_QUAD: 345 newp = &node->sysctl_qdata; 346 break; 347 default: 348 return (EINVAL); 349 } 350 } 351 else 352 newp = node->sysctl_data; 353 354 l = MIN(l, node->sysctl_size); 355 if (oldp != NULL) 356 memcpy(oldp, newp, l); 357 *oldlenp = node->sysctl_size; 358 359 return (0); 360 } 361 362 static size_t 363 __cvt_node_out(uint v, const struct sysctlnode *n, void **o, size_t *l) 364 { 365 const void *src = n; 366 size_t sz; 367 368 switch (v) { 369 #if (SYSCTL_VERSION != SYSCTL_VERS_1) 370 #error __cvt_node_out: no support for SYSCTL_VERSION 371 #endif /* (SYSCTL_VERSION != SYSCTL_VERS_1) */ 372 373 case SYSCTL_VERSION: 374 sz = sizeof(struct sysctlnode); 375 break; 376 377 default: 378 sz = 0; 379 break; 380 } 381 382 if (sz > 0 && *o != NULL && *l >= sz) { 383 memcpy(*o, src, sz); 384 *o = sz + (caddr_t)*o; 385 *l -= sz; 386 } 387 388 return(sz); 389 } 390
Indexes created Sun Sep 28 12:09:53 GMT 2025