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
set_user_str(void * dstp,size_t * dstlenp,const char * src,size_t len,size_t maxlen)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
sysctl(const int * name,u_int namelen,void * oldp,size_t * oldlenp,const void * newp,size_t newlen)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