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/param.h> 33 #include <sys/sysctl.h> 34 35 #include <errno.h> 36 #include <limits.h> 37 #include <paths.h> 38 #include <stdio.h> 39 #include <unistd.h> 40 #include <string.h> 41 42 extern int __sysctl(const int *name, u_int namelen, void *oldp, 43 size_t *oldlenp, const void *newp, size_t newlen); 44 45 static int 46 set_user_str(void *dstp, size_t *dstlenp, const char *src, size_t len, 47 size_t maxlen) 48 { 49 int retval; 50 51 retval = 0; 52 if (dstp != NULL) { 53 if (len > maxlen) { 54 len = maxlen; 55 errno = ENOMEM; 56 retval = -1; 57 } 58 memcpy(dstp, src, len); 59 } 60 *dstlenp = len; 61 return (retval); 62 } 63 64 int 65 sysctl(const int *name, u_int namelen, void *oldp, size_t *oldlenp, 66 const void *newp, size_t newlen) 67 { 68 int retval; 69 size_t orig_oldlen; 70 71 orig_oldlen = oldlenp != NULL ? *oldlenp : 0; 72 retval = __sysctl(name, namelen, oldp, oldlenp, newp, newlen); 73 /* 74 * Valid names under CTL_USER except USER_LOCALBASE have a dummy entry 75 * in the sysctl tree (to support name lookups and enumerations) with 76 * an empty/zero value, and the true value is supplied by this routine. 77 * For all such names, __sysctl() is used solely to validate the name. 78 * 79 * Return here unless there was a successful lookup for a CTL_USER name. 80 */ 81 if (retval != 0 || name[0] != CTL_USER) 82 return (retval); 83 84 if (namelen != 2) { 85 errno = EINVAL; 86 return (-1); 87 } 88 89 /* Variables under CLT_USER that may be overridden by kernel values */ 90 switch (name[1]) { 91 case USER_LOCALBASE: 92 if (oldlenp == NULL || *oldlenp > sizeof("")) 93 return (0); 94 return (set_user_str(oldp, oldlenp, _PATH_LOCALBASE, 95 sizeof(_PATH_LOCALBASE), orig_oldlen)); 96 } 97 98 /* Variables under CLT_USER whose values are immutably defined below */ 99 if (newp != NULL) { 100 errno = EPERM; 101 return (-1); 102 } 103 104 switch (name[1]) { 105 case USER_CS_PATH: 106 return (set_user_str(oldp, oldlenp, _PATH_STDPATH, 107 sizeof(_PATH_STDPATH), orig_oldlen)); 108 } 109 110 if (oldp != NULL && *oldlenp < sizeof(int)) { 111 errno = ENOMEM; 112 return (-1); 113 } 114 *oldlenp = sizeof(int); 115 if (oldp == NULL) 116 return (0); 117 118 switch (name[1]) { 119 case USER_BC_BASE_MAX: 120 *(int *)oldp = BC_BASE_MAX; 121 return (0); 122 case USER_BC_DIM_MAX: 123 *(int *)oldp = BC_DIM_MAX; 124 return (0); 125 case USER_BC_SCALE_MAX: 126 *(int *)oldp = BC_SCALE_MAX; 127 return (0); 128 case USER_BC_STRING_MAX: 129 *(int *)oldp = BC_STRING_MAX; 130 return (0); 131 case USER_COLL_WEIGHTS_MAX: 132 *(int *)oldp = COLL_WEIGHTS_MAX; 133 return (0); 134 case USER_EXPR_NEST_MAX: 135 *(int *)oldp = EXPR_NEST_MAX; 136 return (0); 137 case USER_LINE_MAX: 138 *(int *)oldp = LINE_MAX; 139 return (0); 140 case USER_RE_DUP_MAX: 141 *(int *)oldp = RE_DUP_MAX; 142 return (0); 143 case USER_POSIX2_VERSION: 144 *(int *)oldp = _POSIX2_VERSION; 145 return (0); 146 case USER_POSIX2_C_BIND: 147 #ifdef POSIX2_C_BIND 148 *(int *)oldp = 1; 149 #else 150 *(int *)oldp = 0; 151 #endif 152 return (0); 153 case USER_POSIX2_C_DEV: 154 #ifdef POSIX2_C_DEV 155 *(int *)oldp = 1; 156 #else 157 *(int *)oldp = 0; 158 #endif 159 return (0); 160 case USER_POSIX2_CHAR_TERM: 161 #ifdef POSIX2_CHAR_TERM 162 *(int *)oldp = 1; 163 #else 164 *(int *)oldp = 0; 165 #endif 166 return (0); 167 case USER_POSIX2_FORT_DEV: 168 #ifdef POSIX2_FORT_DEV 169 *(int *)oldp = 1; 170 #else 171 *(int *)oldp = 0; 172 #endif 173 return (0); 174 case USER_POSIX2_FORT_RUN: 175 #ifdef POSIX2_FORT_RUN 176 *(int *)oldp = 1; 177 #else 178 *(int *)oldp = 0; 179 #endif 180 return (0); 181 case USER_POSIX2_LOCALEDEF: 182 #ifdef POSIX2_LOCALEDEF 183 *(int *)oldp = 1; 184 #else 185 *(int *)oldp = 0; 186 #endif 187 return (0); 188 case USER_POSIX2_SW_DEV: 189 #ifdef POSIX2_SW_DEV 190 *(int *)oldp = 1; 191 #else 192 *(int *)oldp = 0; 193 #endif 194 return (0); 195 case USER_POSIX2_UPE: 196 #ifdef POSIX2_UPE 197 *(int *)oldp = 1; 198 #else 199 *(int *)oldp = 0; 200 #endif 201 return (0); 202 case USER_STREAM_MAX: 203 *(int *)oldp = FOPEN_MAX; 204 return (0); 205 case USER_TZNAME_MAX: 206 *(int *)oldp = NAME_MAX; 207 return (0); 208 default: 209 errno = EINVAL; 210 return (-1); 211 } 212 /* NOTREACHED */ 213 } 214