xref: /netbsd-src/sys/compat/freebsd/freebsd_sysctl.c (revision 7fa608457b817eca6e0977b37f758ae064f3c99c)
1 /*	$NetBSD: freebsd_sysctl.c,v 1.9 2007/08/15 12:07:28 ad Exp $	*/
2 
3 /*-
4  * Copyright (c) 2005 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by
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  * FreeBSD compatibility module. Try to deal with various FreeBSD sysctl calls.
41  */
42 
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: freebsd_sysctl.c,v 1.9 2007/08/15 12:07:28 ad Exp $");
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/proc.h>
49 #include <sys/mount.h>
50 #include <sys/signal.h>
51 #include <sys/signalvar.h>
52 #include <sys/malloc.h>
53 #include <sys/mman.h>
54 #include <sys/sysctl.h>
55 #include <sys/ktrace.h>
56 
57 #include <sys/syscallargs.h>
58 
59 #include <compat/freebsd/freebsd_syscallargs.h>
60 #include <compat/common/compat_util.h>
61 #include <compat/freebsd/freebsd_rtprio.h>
62 #include <compat/freebsd/freebsd_timex.h>
63 #include <compat/freebsd/freebsd_signal.h>
64 #include <compat/freebsd/freebsd_mman.h>
65 
66 static int freebsd_sysctl_name2oid(char *, int *, int *);
67 
68 SYSCTL_SETUP_PROTO(freebsd_sysctl_setup);
69 SYSCTL_SETUP(freebsd_sysctl_setup, "freebsd emulated sysctl setup")
70 {
71 	sysctl_createv(clog, 0, NULL, NULL,
72 			CTLFLAG_PERMANENT,
73 			CTLTYPE_NODE, "kern", NULL,
74 			NULL, 0, NULL, 0,
75 			CTL_KERN, CTL_EOL);
76         sysctl_createv(clog, 0, NULL, NULL,
77 			CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
78 			CTLTYPE_INT, "osreldate",
79 			SYSCTL_DESCR("Operating system revision"),
80 			NULL, __NetBSD_Version__, NULL, 0,
81 			CTL_KERN, CTL_CREATE, CTL_EOL);
82 }
83 
84 int
85 freebsd_sys_sysctl(l, v, retval)
86 	struct lwp *l;
87 	void *v;
88 	register_t *retval;
89 {
90 	struct freebsd_sys_sysctl_args /* {
91 		syscallarg(int *) name;
92 		syscallarg(u_int) namelen;
93 		syscallarg(void *) old;
94 		syscallarg(size_t *) oldlenp;
95 		syscallarg(void *) new;
96 		syscallarg(size_t) newlen;
97 	} */ *uap = v;
98 	int error;
99 	int name[CTL_MAXNAME];
100 	size_t newlen, *oldlenp;
101 	u_int namelen;
102 	void *new, *old;
103 
104 	namelen = SCARG(uap, namelen);
105 
106 	if ((namelen > CTL_MAXNAME) || (namelen < 1))
107 		return EINVAL;
108 
109 	if ((error = copyin(SCARG(uap, name), name,
110 	    namelen * sizeof(*name))) != 0)
111 		return error;
112 
113 	if (namelen > 0 && name[0] != 0)
114 		return(sys___sysctl(l, v, retval));
115 
116 	ktrmib(name, namelen);
117 
118 	/*
119 	 * FreeBSD sysctl uses an undocumented set of special OIDs in it's
120 	 * sysctl MIB whose tree is rooted at oid 0.  These OIDs are
121 	 * interpretted by their sysctl to implement functions that NetBSD
122 	 * performs in libc, such as sysctlgetmibinfo.
123 	 *
124 	 * From the FreeBSD kern_sysctl.c, these OIDs are:
125 	 * {0,0}        printf the entire MIB-tree.
126 	 * {0,1,...}    return the name of the "..." OID.
127 	 * {0,2,...}    return the next OID.
128 	 * {0,3}        return the OID of the name in "new"
129 	 * {0,4,...}    return the kind & format info for the "..." OID.
130 	 * {0,5,...}    return the description the "..." OID.
131 	 *
132 	 * Only implement {0,3} for now.
133 	 */
134 
135 	if (namelen < 2 || namelen > CTL_MAXNAME)
136 		return(EINVAL);
137 
138 	if (name[1] == 3) {
139 		char *locnew;
140 		int oid[CTL_MAXNAME];
141 		u_int oidlen = CTL_MAXNAME;
142 
143 		new = SCARG(uap, new);
144 		newlen = SCARG(uap, newlen);
145 		if (new == NULL || newlen < 1 ||
146 		    newlen > (SYSCTL_NAMELEN * CTL_MAXNAME))
147 			return(EINVAL);
148 
149 		old = SCARG(uap, old);
150 		oldlenp = SCARG(uap, oldlenp);
151 		if (old == NULL || oldlenp == NULL || *oldlenp < sizeof(int))
152 			return(EINVAL);
153 
154 		if ((locnew =
155 		     (char *) malloc(newlen + 1, M_TEMP, M_WAITOK)) == NULL)
156 			return(ENOMEM);
157 
158 		if ((error = copyinstr(new, locnew, newlen + 1, NULL)) ||
159 		    (error = sysctl_lock(l, old, *oldlenp))) {
160 			free(locnew, M_TEMP);
161 			return(error);
162 		}
163 
164 		ktrmibio(-1, UIO_WRITE, new, newlen + 1, error);
165 		error = freebsd_sysctl_name2oid(locnew, oid, &oidlen);
166 		sysctl_unlock(l);
167 		free(locnew, M_TEMP);
168 		if (error)
169 			return(error);
170 
171 		oidlen *= sizeof(int);
172 		error = copyout(oid, SCARG(uap, old),
173 				MIN(oidlen, *SCARG(uap, oldlenp)));
174 		if (error)
175 			return(error);
176 		ktrmibio(-1, UIO_READ, SCARG(uap, old),
177 		    MIN(oidlen, *SCARG(uap, oldlenp)),  0);
178 
179 		error = copyout(&oidlen, SCARG(uap, oldlenp), sizeof(u_int));
180 
181 		return(error);
182 	}
183 
184 	return(EOPNOTSUPP);
185 }
186 
187 static int
188 freebsd_sysctl_name2oid(char *name, int *oid, int *oidlen)
189 {
190 	char *dot;
191 	int oi, ci;
192 	struct sysctlnode *node, *pnode;
193 
194 	pnode = &sysctl_root;
195 	node = sysctl_root.sysctl_child;
196 	oi = 0;
197 	if ((dot = strchr(name, (int)'.')) != NULL)
198 		*dot++ = '\0';
199 
200 next:
201 	while (*name != '\0' && node != NULL) {
202 		for (ci = 0; ci < pnode->sysctl_clen; ci++) {
203 			if (strcmp(name, node[ci].sysctl_name) == 0) {
204 				oid[oi++] = node[ci].sysctl_num;
205 				if ((name = dot) == NULL) {
206 					*oidlen = oi;
207 					return(0);
208 				}
209 				if ((dot = strchr(name, (int)'.')) != NULL)
210 					*dot++ = '\0';
211 
212 				if (SYSCTL_TYPE(node[ci].sysctl_flags) !=
213 				    CTLTYPE_NODE)
214 					return(ENOTDIR);
215 
216 				pnode = &node[ci];
217 				node = pnode->sysctl_child;
218 				goto next;
219 			}
220 		}
221 
222 		/* no more nodes, it must not exist */
223 		break;
224 	}
225 
226 	return(ENOENT);
227 }
228