xref: /netbsd-src/sys/compat/freebsd/freebsd_sysctl.c (revision ce2c90c7c172d95d2402a5b3d96d8f8e6d138a21)
1 /*	$NetBSD: freebsd_sysctl.c,v 1.7 2006/09/24 21:44:58 dbj 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 1.7 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/proc.h>
53 #include <sys/mount.h>
54 #include <sys/signal.h>
55 #include <sys/signalvar.h>
56 #include <sys/malloc.h>
57 #include <sys/mman.h>
58 #include <sys/sysctl.h>
59 #ifdef KTRACE
60 #include <sys/ktrace.h>
61 #endif
62 
63 #include <sys/sa.h>
64 #include <sys/syscallargs.h>
65 
66 #include <compat/freebsd/freebsd_syscallargs.h>
67 #include <compat/common/compat_util.h>
68 #include <compat/freebsd/freebsd_rtprio.h>
69 #include <compat/freebsd/freebsd_timex.h>
70 #include <compat/freebsd/freebsd_signal.h>
71 #include <compat/freebsd/freebsd_mman.h>
72 
73 static int freebsd_sysctl_name2oid(char *, int *, int *);
74 
75 SYSCTL_SETUP_PROTO(freebsd_sysctl_setup);
76 SYSCTL_SETUP(freebsd_sysctl_setup, "freebsd emulated sysctl setup")
77 {
78 	sysctl_createv(clog, 0, NULL, NULL,
79 			CTLFLAG_PERMANENT,
80 			CTLTYPE_NODE, "kern", NULL,
81 			NULL, 0, NULL, 0,
82 			CTL_KERN, CTL_EOL);
83         sysctl_createv(clog, 0, NULL, NULL,
84 			CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
85 			CTLTYPE_INT, "osreldate",
86 			SYSCTL_DESCR("Operating system revision"),
87 			NULL, __NetBSD_Version__, NULL, 0,
88 			CTL_KERN, CTL_CREATE, CTL_EOL);
89 }
90 
91 int
92 freebsd_sys_sysctl(l, v, retval)
93 	struct lwp *l;
94 	void *v;
95 	register_t *retval;
96 {
97 	struct freebsd_sys_sysctl_args /* {
98 		syscallarg(int *) name;
99 		syscallarg(u_int) namelen;
100 		syscallarg(void *) old;
101 		syscallarg(size_t *) oldlenp;
102 		syscallarg(void *) new;
103 		syscallarg(size_t) newlen;
104 	} */ *uap = v;
105 	int error;
106 	int name[CTL_MAXNAME];
107 	size_t newlen, *oldlenp;
108 	u_int namelen;
109 	void *new, *old;
110 
111 	namelen = SCARG(uap, namelen);
112 
113 	if ((namelen > CTL_MAXNAME) || (namelen < 1))
114 		return EINVAL;
115 
116 	if ((error = copyin(SCARG(uap, name), name,
117 	    namelen * sizeof(*name))) != 0)
118 		return error;
119 
120 	if (namelen > 0 && name[0] != 0)
121 		return(sys___sysctl(l, v, retval));
122 
123 #ifdef KTRACE
124 	if (KTRPOINT(l->l_proc, KTR_MIB))
125 		ktrmib(l, name, namelen);
126 #endif
127 
128 	/*
129 	 * FreeBSD sysctl uses an undocumented set of special OIDs in it's
130 	 * sysctl MIB whose tree is rooted at oid 0.  These OIDs are
131 	 * interpretted by their sysctl to implement functions that NetBSD
132 	 * performs in libc, such as sysctlgetmibinfo.
133 	 *
134 	 * From the FreeBSD kern_sysctl.c, these OIDs are:
135 	 * {0,0}        printf the entire MIB-tree.
136 	 * {0,1,...}    return the name of the "..." OID.
137 	 * {0,2,...}    return the next OID.
138 	 * {0,3}        return the OID of the name in "new"
139 	 * {0,4,...}    return the kind & format info for the "..." OID.
140 	 * {0,5,...}    return the description the "..." OID.
141 	 *
142 	 * Only implement {0,3} for now.
143 	 */
144 
145 	if (namelen < 2 || namelen > CTL_MAXNAME)
146 		return(EINVAL);
147 
148 	if (name[1] == 3) {
149 		char *locnew;
150 		int oid[CTL_MAXNAME];
151 		u_int oidlen = CTL_MAXNAME;
152 
153 		new = SCARG(uap, new);
154 		newlen = SCARG(uap, newlen);
155 		if (new == NULL || newlen < 1 ||
156 		    newlen > (SYSCTL_NAMELEN * CTL_MAXNAME))
157 			return(EINVAL);
158 
159 		old = SCARG(uap, old);
160 		oldlenp = SCARG(uap, oldlenp);
161 		if (old == NULL || oldlenp == NULL || *oldlenp < sizeof(int))
162 			return(EINVAL);
163 
164 		if ((locnew =
165 		     (char *) malloc(newlen + 1, M_TEMP, M_WAITOK)) == NULL)
166 			return(ENOMEM);
167 
168 		if ((error = copyinstr(new, locnew, newlen + 1, NULL)) ||
169 		    (error = sysctl_lock(l, old, *oldlenp))) {
170 			free(locnew, M_TEMP);
171 			return(error);
172 		}
173 #ifdef KTRACE
174 		if (!error && KTRPOINT(l->l_proc, KTR_MIB)) {
175 			struct iovec iov;
176 
177 			iov.iov_base = new;
178 			iov.iov_len = newlen + 1;
179 			ktrgenio(l, -1, UIO_WRITE, &iov, newlen + 1, 0);
180 		}
181 #endif
182 
183 		error = freebsd_sysctl_name2oid(locnew, oid, &oidlen);
184 		sysctl_unlock(l);
185 		free(locnew, M_TEMP);
186 		if (error)
187 			return(error);
188 
189 		oidlen *= sizeof(int);
190 		error = copyout(oid, SCARG(uap, old),
191 				MIN(oidlen, *SCARG(uap, oldlenp)));
192 		if (error)
193 			return(error);
194 #ifdef KTRACE
195 		if (KTRPOINT(l->l_proc, KTR_MIB)) {
196 			struct iovec iov;
197 
198 			iov.iov_base = SCARG(uap, old);
199 			iov.iov_len = MIN(oidlen, *SCARG(uap, oldlenp));
200 			ktrgenio(l, -1, UIO_READ, &iov, iov.iov_len, 0);
201 		}
202 #endif
203 		error = copyout(&oidlen, SCARG(uap, oldlenp), sizeof(u_int));
204 
205 		return(error);
206 	}
207 
208 	return(EOPNOTSUPP);
209 }
210 
211 static int
212 freebsd_sysctl_name2oid(char *name, int *oid, int *oidlen)
213 {
214 	char *dot;
215 	int oi, ci;
216 	struct sysctlnode *node, *pnode;
217 
218 	pnode = &sysctl_root;
219 	node = sysctl_root.sysctl_child;
220 	oi = 0;
221 	if ((dot = strchr(name, (int)'.')) != NULL)
222 		*dot++ = '\0';
223 
224 next:
225 	while (*name != '\0' && node != NULL) {
226 		for (ci = 0; ci < pnode->sysctl_clen; ci++) {
227 			if (strcmp(name, node[ci].sysctl_name) == 0) {
228 				oid[oi++] = node[ci].sysctl_num;
229 				if ((name = dot) == NULL) {
230 					*oidlen = oi;
231 					return(0);
232 				}
233 				if ((dot = strchr(name, (int)'.')) != NULL)
234 					*dot++ = '\0';
235 
236 				if (SYSCTL_TYPE(node[ci].sysctl_flags) !=
237 				    CTLTYPE_NODE)
238 					return(ENOTDIR);
239 
240 				pnode = &node[ci];
241 				node = pnode->sysctl_child;
242 				goto next;
243 			}
244 		}
245 
246 		/* no more nodes, it must not exist */
247 		break;
248 	}
249 
250 	return(ENOENT);
251 }
252