sysctl.c revision 1.14
1/*	$NetBSD: sysctl.c,v 1.14 2003/12/04 19:40:55 atatat 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
35static char sccsid[] = "@(#)sysctl.c	8.2 (Berkeley) 1/4/94";
36#else
37__RCSID("$NetBSD: sysctl.c,v 1.14 2003/12/04 19:40:55 atatat Exp $");
38#endif
39#endif /* LIBC_SCCS and not lint */
40
41#include "namespace.h"
42#include <sys/param.h>
43#define __USE_NEW_SYSCTL
44#include <sys/sysctl.h>
45
46#include <errno.h>
47#include <paths.h>
48#include <stdio.h>
49#include <string.h>
50#include <unistd.h>
51#include "extern.h"
52
53#ifdef __weak_alias
54__weak_alias(sysctl,_sysctl)
55#endif
56
57/*
58 * handles requests off the user subtree
59 */
60static int user_sysctl(int *, u_int, void *, size_t *, const void *, size_t);
61
62#include <stdlib.h>
63
64int
65sysctl(name, namelen, oldp, oldlenp, newp, newlen)
66	int *name;
67	unsigned int namelen;
68	void *oldp;
69	const void *newp;
70	size_t *oldlenp, newlen;
71{
72	size_t oldlen, savelen;
73	int error;
74
75	if (name[0] != CTL_USER)
76		/* LINTED will fix when sysctl interface gets corrected */
77		/* XXX when will that be? */
78		return (__sysctl(name, namelen, oldp, oldlenp,
79				 (void *)newp, newlen));
80
81	oldlen = (oldlenp == NULL) ? 0 : *oldlenp;
82	savelen = oldlen;
83	error = user_sysctl(name + 1, namelen - 1, oldp, &oldlen, newp, newlen);
84
85	if (error != 0) {
86		errno = error;
87		return (-1);
88	}
89
90	if (oldlenp != NULL) {
91		*oldlenp = oldlen;
92		if (oldp != NULL && oldlen > savelen) {
93			errno = ENOMEM;
94			return (-1);
95		}
96	}
97
98	return (0);
99}
100
101static int
102user_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
103	int *name;
104	unsigned int namelen;
105	void *oldp;
106	const void *newp;
107	size_t *oldlenp, newlen;
108{
109#define _INT(s, n, v) {						\
110	.sysctl_flags = SYSCTL_IMMEDIATE|SYSCTL_PERMANENT|SYSCTL_READONLY| \
111			SYSCTL_TYPE(CTLTYPE_INT),		\
112	.sysctl_size = sizeof(int),				\
113	.sysctl_name = (s),					\
114	.sysctl_num = (n),					\
115	.sysctl_un = { .scu_idata = (v), }, }
116
117	/*
118	 * the nodes under the "user" node
119	 */
120	static const struct sysctlnode sysctl_usermib[] = {
121#if defined(lint)
122		/*
123		 * lint doesn't like my initializers
124		 */
125		0
126#else /* !lint */
127		{
128			.sysctl_flags = SYSCTL_READONLY|SYSCTL_PERMANENT|
129				SYSCTL_TYPE(CTLTYPE_STRING),
130			.sysctl_size = sizeof(_PATH_STDPATH),
131			.sysctl_name = "cs_path",
132			.sysctl_num = USER_CS_PATH,
133			.sysctl_un = { .scu_data = _PATH_STDPATH, },
134		},
135		_INT("bc_base_max", USER_BC_BASE_MAX, BC_BASE_MAX),
136		_INT("bc_dim_max", USER_BC_DIM_MAX, BC_DIM_MAX),
137		_INT("bc_scale_max", USER_BC_SCALE_MAX, BC_SCALE_MAX),
138		_INT("bc_string_max", USER_BC_STRING_MAX, BC_STRING_MAX),
139		_INT("coll_weights_max", USER_COLL_WEIGHTS_MAX,
140		     COLL_WEIGHTS_MAX),
141		_INT("expr_nest_max", USER_EXPR_NEST_MAX, EXPR_NEST_MAX),
142		_INT("line_max", USER_LINE_MAX, LINE_MAX),
143		_INT("re_dup_max", USER_RE_DUP_MAX, RE_DUP_MAX),
144		_INT("posix2_version", USER_POSIX2_VERSION, _POSIX2_VERSION),
145#ifdef POSIX2_C_BIND
146		_INT("posix2_c_bind", USER_POSIX2_C_BIND, 1),
147#else
148		_INT("posix2_c_bind", USER_POSIX2_C_BIND, 0),
149#endif
150#ifdef POSIX2_C_DEV
151		_INT("posix2_c_dev", USER_POSIX2_C_DEV, 1),
152#else
153		_INT("posix2_c_dev", USER_POSIX2_C_DEV, 0),
154#endif
155#ifdef POSIX2_CHAR_TERM
156		_INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 1),
157#else
158		_INT("posix2_char_term", USER_POSIX2_CHAR_TERM, 0),
159#endif
160#ifdef POSIX2_FORT_DEV
161		_INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 1),
162#else
163		_INT("posix2_fort_dev", USER_POSIX2_FORT_DEV, 0),
164#endif
165#ifdef POSIX2_FORT_RUN
166		_INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 1),
167#else
168		_INT("posix2_fort_run", USER_POSIX2_FORT_RUN, 0),
169#endif
170#ifdef POSIX2_LOCALEDEF
171		_INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 1),
172#else
173		_INT("posix2_localedef", USER_POSIX2_LOCALEDEF, 0),
174#endif
175#ifdef POSIX2_SW_DEV
176		_INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 1),
177#else
178		_INT("posix2_sw_dev", USER_POSIX2_SW_DEV, 0),
179#endif
180#ifdef POSIX2_UPE
181		_INT("posix2_upe", USER_POSIX2_UPE, 1),
182#else
183		_INT("posix2_upe", USER_POSIX2_UPE, 0),
184#endif
185		_INT("stream_max", USER_STREAM_MAX, FOPEN_MAX),
186		_INT("tzname_max", USER_TZNAME_MAX, NAME_MAX),
187		_INT("atexit_max", USER_ATEXIT_MAX, -1),
188#endif /* !lint */
189	};
190#undef _INT
191
192	static const int clen = sizeof(sysctl_usermib) /
193		sizeof(sysctl_usermib[0]);
194
195	const struct sysctlnode *node;
196	int ni;
197	size_t l, sz;
198
199	/*
200	 * none of these nodes are writable and they're all terminal (for now)
201	 */
202	if (newp != NULL || newlen != 0)
203		return (EPERM);
204	if (namelen != 1)
205		return (EINVAL);
206
207	l = *oldlenp;
208	if (name[0] == CTL_QUERY) {
209		sz = clen * sizeof(struct sysctlnode);
210		l = MIN(l, sz);
211		if (oldp != NULL)
212			memcpy(oldp, &sysctl_usermib[0], l);
213		*oldlenp = sz;
214		return (0);
215	}
216
217	node = &sysctl_usermib[0];
218	for (ni = 0; ni	< clen; ni++)
219		if (name[0] == node[ni].sysctl_num)
220			break;
221	if (ni == clen)
222		return (EOPNOTSUPP);
223
224	node = &node[ni];
225	if (node->sysctl_flags & SYSCTL_IMMEDIATE) {
226		switch (SYSCTL_TYPE(node->sysctl_flags)) {
227		case CTLTYPE_INT:
228			newp = &node->sysctl_idata;
229			break;
230		case CTLTYPE_QUAD:
231			newp = &node->sysctl_qdata;
232			break;
233		default:
234			return (EINVAL);
235		}
236	}
237	else
238		newp = node->sysctl_data;
239
240	l = MIN(l, node->sysctl_size);
241	if (oldp != NULL)
242		memcpy(oldp, newp, l);
243	*oldlenp = node->sysctl_size;
244
245	return (0);
246}
247