1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 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 __SCCSID("@(#)sysctl.c 8.2 (Berkeley) 1/4/94"); 34 __FBSDID("$FreeBSD$"); 35 36 #include <sys/param.h> 37 #include <sys/sysctl.h> 38 39 #include <errno.h> 40 #include <limits.h> 41 #include <paths.h> 42 #include <stdio.h> 43 #include <unistd.h> 44 #include <string.h> 45 46 extern int __sysctl(const int *name, u_int namelen, void *oldp, 47 size_t *oldlenp, const void *newp, size_t newlen); 48 49 static int 50 set_user_str(void *dstp, size_t *dstlenp, const char *src, size_t len, 51 size_t maxlen) 52 { 53 int retval; 54 55 retval = 0; 56 if (dstp != NULL) { 57 if (len > maxlen) { 58 len = maxlen; 59 errno = ENOMEM; 60 retval = -1; 61 } 62 memcpy(dstp, src, len); 63 } 64 *dstlenp = len; 65 return (retval); 66 } 67 68 int 69 sysctl(const int *name, u_int namelen, void *oldp, size_t *oldlenp, 70 const void *newp, size_t newlen) 71 { 72 int retval; 73 size_t orig_oldlen; 74 75 orig_oldlen = oldlenp != NULL ? *oldlenp : 0; 76 retval = __sysctl(name, namelen, oldp, oldlenp, newp, newlen); 77 /* 78 * Valid names under CTL_USER except USER_LOCALBASE have a dummy entry 79 * in the sysctl tree (to support name lookups and enumerations) with 80 * an empty/zero value, and the true value is supplied by this routine. 81 * For all such names, __sysctl() is used solely to validate the name. 82 * 83 * Return here unless there was a successful lookup for a CTL_USER name. 84 */ 85 if (retval != 0 || name[0] != CTL_USER) 86 return (retval); 87 88 if (namelen != 2) { 89 errno = EINVAL; 90 return (-1); 91 } 92 93 /* Variables under CLT_USER that may be overridden by kernel values */ 94 switch (name[1]) { 95 case USER_LOCALBASE: 96 if (oldlenp == NULL || *oldlenp > sizeof("")) 97 return (0); 98 return (set_user_str(oldp, oldlenp, _PATH_LOCALBASE, 99 sizeof(_PATH_LOCALBASE), orig_oldlen)); 100 } 101 102 /* Variables under CLT_USER whose values are immutably defined below */ 103 if (newp != NULL) { 104 errno = EPERM; 105 return (-1); 106 } 107 108 switch (name[1]) { 109 case USER_CS_PATH: 110 return (set_user_str(oldp, oldlenp, _PATH_STDPATH, 111 sizeof(_PATH_STDPATH), orig_oldlen)); 112 } 113 114 if (oldp != NULL && *oldlenp < sizeof(int)) { 115 errno = ENOMEM; 116 return (-1); 117 } 118 *oldlenp = sizeof(int); 119 if (oldp == NULL) 120 return (0); 121 122 switch (name[1]) { 123 case USER_BC_BASE_MAX: 124 *(int *)oldp = BC_BASE_MAX; 125 return (0); 126 case USER_BC_DIM_MAX: 127 *(int *)oldp = BC_DIM_MAX; 128 return (0); 129 case USER_BC_SCALE_MAX: 130 *(int *)oldp = BC_SCALE_MAX; 131 return (0); 132 case USER_BC_STRING_MAX: 133 *(int *)oldp = BC_STRING_MAX; 134 return (0); 135 case USER_COLL_WEIGHTS_MAX: 136 *(int *)oldp = COLL_WEIGHTS_MAX; 137 return (0); 138 case USER_EXPR_NEST_MAX: 139 *(int *)oldp = EXPR_NEST_MAX; 140 return (0); 141 case USER_LINE_MAX: 142 *(int *)oldp = LINE_MAX; 143 return (0); 144 case USER_RE_DUP_MAX: 145 *(int *)oldp = RE_DUP_MAX; 146 return (0); 147 case USER_POSIX2_VERSION: 148 *(int *)oldp = _POSIX2_VERSION; 149 return (0); 150 case USER_POSIX2_C_BIND: 151 #ifdef POSIX2_C_BIND 152 *(int *)oldp = 1; 153 #else 154 *(int *)oldp = 0; 155 #endif 156 return (0); 157 case USER_POSIX2_C_DEV: 158 #ifdef POSIX2_C_DEV 159 *(int *)oldp = 1; 160 #else 161 *(int *)oldp = 0; 162 #endif 163 return (0); 164 case USER_POSIX2_CHAR_TERM: 165 #ifdef POSIX2_CHAR_TERM 166 *(int *)oldp = 1; 167 #else 168 *(int *)oldp = 0; 169 #endif 170 return (0); 171 case USER_POSIX2_FORT_DEV: 172 #ifdef POSIX2_FORT_DEV 173 *(int *)oldp = 1; 174 #else 175 *(int *)oldp = 0; 176 #endif 177 return (0); 178 case USER_POSIX2_FORT_RUN: 179 #ifdef POSIX2_FORT_RUN 180 *(int *)oldp = 1; 181 #else 182 *(int *)oldp = 0; 183 #endif 184 return (0); 185 case USER_POSIX2_LOCALEDEF: 186 #ifdef POSIX2_LOCALEDEF 187 *(int *)oldp = 1; 188 #else 189 *(int *)oldp = 0; 190 #endif 191 return (0); 192 case USER_POSIX2_SW_DEV: 193 #ifdef POSIX2_SW_DEV 194 *(int *)oldp = 1; 195 #else 196 *(int *)oldp = 0; 197 #endif 198 return (0); 199 case USER_POSIX2_UPE: 200 #ifdef POSIX2_UPE 201 *(int *)oldp = 1; 202 #else 203 *(int *)oldp = 0; 204 #endif 205 return (0); 206 case USER_STREAM_MAX: 207 *(int *)oldp = FOPEN_MAX; 208 return (0); 209 case USER_TZNAME_MAX: 210 *(int *)oldp = NAME_MAX; 211 return (0); 212 default: 213 errno = EINVAL; 214 return (-1); 215 } 216 /* NOTREACHED */ 217 } 218