xref: /netbsd-src/sys/compat/linux/common/linux_sysctl.c (revision b7ae68fde0d8ef1c03714e8bbb1ee7c6118ea93b)
1 /*	$NetBSD: linux_sysctl.c,v 1.22 2006/09/24 21:44:58 dbj Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Brown.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed by the NetBSD
21  *      Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * sysctl system call.
41  */
42 
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: linux_sysctl.c,v 1.22 2006/09/24 21:44:58 dbj Exp $");
45 
46 #if defined (_KERNEL_OPT)
47 #include "opt_ktrace.h"
48 #endif
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/errno.h>
53 #include <sys/proc.h>
54 #include <sys/mount.h>
55 #include <sys/sysctl.h>
56 #include <sys/sa.h>
57 #include <sys/syscallargs.h>
58 #ifdef KTRACE
59 #include <sys/ktrace.h>
60 #endif
61 
62 #include <compat/linux/common/linux_types.h>
63 #include <compat/linux/common/linux_signal.h>
64 
65 #include <compat/linux/linux_syscallargs.h>
66 #include <compat/linux/common/linux_sysctl.h>
67 #include <compat/linux/common/linux_exec.h>
68 
69 char linux_sysname[128] = "Linux";
70 #if defined(__amd64__) || defined(__i386__) || defined(__powerpc__)
71 char linux_release[128] = "2.4.18";
72 char linux_version[128] = "#0 Wed Feb 20 20:00:02 CET 2002";
73 #else
74 char linux_release[128] = "2.0.38";
75 char linux_version[128] = "#0 Sun Nov 11 11:11:11 MET 2000";
76 #endif
77 
78 #ifndef _LKM
79 static
80 #endif
81 struct sysctlnode linux_sysctl_root = {
82 	.sysctl_flags = SYSCTL_VERSION|
83 	    CTLFLAG_ROOT|CTLTYPE_NODE|CTLFLAG_READWRITE,
84 	.sysctl_num = 0,
85 	.sysctl_name = "(linux_root)",
86 	sysc_init_field(_sysctl_size, sizeof(struct sysctlnode)),
87 };
88 
89 /*
90  * setup for small sysctl tree used by emulation
91  */
92 SYSCTL_SETUP(linux_sysctl_setup, "linux emulated sysctl subtree setup")
93 {
94 	const struct sysctlnode *node = &linux_sysctl_root;
95 
96 	sysctl_createv(clog, 0, &node, &node,
97 		       CTLFLAG_PERMANENT,
98 		       CTLTYPE_NODE, "kern", NULL,
99 		       NULL, 0, NULL, 0,
100 		       LINUX_CTL_KERN, CTL_EOL);
101 
102 	sysctl_createv(clog, 0, &node, NULL,
103 		       CTLFLAG_PERMANENT,
104 		       CTLTYPE_STRING, "ostype", NULL,
105 		       NULL, 0, linux_sysname, sizeof(linux_sysname),
106 		       LINUX_KERN_OSTYPE, CTL_EOL);
107 	sysctl_createv(clog, 0, &node, NULL,
108 		       CTLFLAG_PERMANENT,
109 		       CTLTYPE_STRING, "osrelease", NULL,
110 		       NULL, 0, linux_release, sizeof(linux_release),
111 		       LINUX_KERN_OSRELEASE, CTL_EOL);
112 	sysctl_createv(clog, 0, &node, NULL,
113 		       CTLFLAG_PERMANENT,
114 		       CTLTYPE_STRING, "version", NULL,
115 		       NULL, 0, linux_version, sizeof(linux_version),
116 		       LINUX_KERN_VERSION, CTL_EOL);
117 
118 	linux_sysctl_root.sysctl_flags &= ~CTLFLAG_READWRITE;
119 }
120 
121 /*
122  * linux sysctl system call
123  */
124 int
125 linux_sys___sysctl(struct lwp *l, void *v, register_t *retval)
126 {
127 	struct linux_sys___sysctl_args *uap = v;
128 	struct linux___sysctl ls;
129 	int error, nerror, name[CTL_MAXNAME];
130 	size_t savelen = 0, oldlen = 0;
131 
132 	/*
133 	 * get linux args structure
134 	 */
135 	if ((error = copyin(SCARG(uap, lsp), &ls, sizeof(ls))))
136 		return error;
137 
138 	/*
139 	 * get oldlen
140 	 */
141 	oldlen = 0;
142 	if (ls.oldlenp != NULL) {
143 		error = copyin(ls.oldlenp, &oldlen, sizeof(oldlen));
144 		if (error)
145 			return (error);
146 	}
147 	savelen = oldlen;
148 
149 	/*
150 	 * top-level sysctl names may or may not be non-terminal, but
151 	 * we don't care
152 	 */
153 	if (ls.nlen > CTL_MAXNAME || ls.nlen < 1)
154 		return (EINVAL);
155 	error = copyin(ls.name, &name, ls.nlen * sizeof(int));
156 	if (error)
157 		return (error);
158 
159 #ifdef KTRACE
160        if (KTRPOINT(l->l_proc, KTR_MIB))
161                ktrmib(l, name, ls.nlen);
162 #endif
163 	/*
164 	 * wire old so that copyout() is less likely to fail?
165 	 */
166 	error = sysctl_lock(l, ls.oldval, savelen);
167 	if (error)
168 		return (error);
169 
170 	/*
171 	 * dispatch request into linux sysctl tree
172 	 */
173 	error = sysctl_dispatch(&name[0], ls.nlen,
174 				ls.oldval, &oldlen,
175 				ls.newval, ls.newlen,
176 				&name[0], l, &linux_sysctl_root);
177 
178 	/*
179 	 * release the sysctl lock
180 	 */
181 	sysctl_unlock(l);
182 
183 	/*
184 	 * reset caller's oldlen, even if we got an error
185 	 */
186 	if (ls.oldlenp) {
187 		nerror = copyout(&oldlen, ls.oldlenp, sizeof(oldlen));
188 		if (error == 0)
189 			error = nerror;
190 	}
191 
192 	/*
193 	 * if the only problem is that we weren't given enough space,
194 	 * that's an ENOMEM error
195 	 */
196 	if (error == 0 && ls.oldval != NULL && savelen < oldlen)
197 		error = ENOMEM;
198 
199 	return (error);
200 }
201 
202 /*
203  * kernel related system variables under emul.linux in the main sysctl
204  * tree
205  */
206 SYSCTL_SETUP(sysctl_emul_linux_setup, "sysctl emul.linux subtree setup")
207 {
208 
209 	sysctl_createv(clog, 0, NULL, NULL,
210 		       CTLFLAG_PERMANENT,
211 		       CTLTYPE_NODE, "emul", NULL,
212 		       NULL, 0, NULL, 0,
213 		       CTL_EMUL, CTL_EOL);
214 	sysctl_createv(clog, 0, NULL, NULL,
215 		       CTLFLAG_PERMANENT,
216 		       CTLTYPE_NODE, "linux",
217 		       SYSCTL_DESCR("Linux emulation settings"),
218 		       NULL, 0, NULL, 0,
219 		       CTL_EMUL, EMUL_LINUX, CTL_EOL);
220 	sysctl_createv(clog, 0, NULL, NULL,
221 		       CTLFLAG_PERMANENT,
222 		       CTLTYPE_NODE, "kern",
223 		       SYSCTL_DESCR("Linux kernel emulation settings"),
224 		       NULL, 0, NULL, 0,
225 		       CTL_EMUL, EMUL_LINUX, EMUL_LINUX_KERN, CTL_EOL);
226 
227 	sysctl_createv(clog, 0, NULL, NULL,
228 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
229 		       CTLTYPE_STRING, "ostype",
230 		       SYSCTL_DESCR("Linux operating system type"),
231 		       NULL, 0, linux_sysname, sizeof(linux_sysname),
232 		       CTL_EMUL, EMUL_LINUX, EMUL_LINUX_KERN,
233 		       EMUL_LINUX_KERN_OSTYPE, CTL_EOL);
234 	sysctl_createv(clog, 0, NULL, NULL,
235 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
236 		       CTLTYPE_STRING, "osrelease",
237 		       SYSCTL_DESCR("Linux operating system release"),
238 		       NULL, 0, linux_release, sizeof(linux_release),
239 		       CTL_EMUL, EMUL_LINUX, EMUL_LINUX_KERN,
240 		       EMUL_LINUX_KERN_OSRELEASE, CTL_EOL);
241 	sysctl_createv(clog, 0, NULL, NULL,
242 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
243 		       CTLTYPE_STRING, "osversion",
244 		       SYSCTL_DESCR("Linux operating system revision"),
245 		       NULL, 0, linux_version, sizeof(linux_version),
246 		       CTL_EMUL, EMUL_LINUX, EMUL_LINUX_KERN,
247 		       EMUL_LINUX_KERN_VERSION, CTL_EOL);
248 }
249