xref: /freebsd/sys/kern/kern_mib.c (revision b52b9d56d4e96089873a75f9e29062eec19fabba)
1 /*-
2  * Copyright (c) 1982, 1986, 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Mike Karels at Berkeley Software Design, Inc.
7  *
8  * Quite extensively rewritten by Poul-Henning Kamp of the FreeBSD
9  * project, to make these variables more userfriendly.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  *
39  *	@(#)kern_sysctl.c	8.4 (Berkeley) 4/14/94
40  * $FreeBSD$
41  */
42 
43 #include "opt_posix.h"
44 
45 #include <sys/param.h>
46 #include <sys/kernel.h>
47 #include <sys/systm.h>
48 #include <sys/sysctl.h>
49 #include <sys/proc.h>
50 #include <sys/lock.h>
51 #include <sys/mutex.h>
52 #include <sys/jail.h>
53 #include <sys/smp.h>
54 
55 SYSCTL_NODE(, 0,	  sysctl, CTLFLAG_RW, 0,
56 	"Sysctl internal magic");
57 SYSCTL_NODE(, CTL_KERN,	  kern,   CTLFLAG_RW, 0,
58 	"High kernel, proc, limits &c");
59 SYSCTL_NODE(, CTL_VM,	  vm,     CTLFLAG_RW, 0,
60 	"Virtual memory");
61 SYSCTL_NODE(, CTL_VFS,	  vfs,     CTLFLAG_RW, 0,
62 	"File system");
63 SYSCTL_NODE(, CTL_NET,	  net,    CTLFLAG_RW, 0,
64 	"Network, (see socket.h)");
65 SYSCTL_NODE(, CTL_DEBUG,  debug,  CTLFLAG_RW, 0,
66 	"Debugging");
67 SYSCTL_NODE(_debug, OID_AUTO,  sizeof,  CTLFLAG_RW, 0,
68 	"Sizeof various things");
69 SYSCTL_NODE(, CTL_HW,	  hw,     CTLFLAG_RW, 0,
70 	"hardware");
71 SYSCTL_NODE(, CTL_MACHDEP, machdep, CTLFLAG_RW, 0,
72 	"machine dependent");
73 SYSCTL_NODE(, CTL_USER,	  user,   CTLFLAG_RW, 0,
74 	"user-level");
75 SYSCTL_NODE(, CTL_P1003_1B,  p1003_1b,   CTLFLAG_RW, 0,
76 	"p1003_1b, (see p1003_1b.h)");
77 
78 SYSCTL_NODE(, OID_AUTO,  compat, CTLFLAG_RW, 0,
79 	"Compatibility code");
80 SYSCTL_NODE(, OID_AUTO, security, CTLFLAG_RW, 0,
81      	"Security");
82 #ifdef REGRESSION
83 SYSCTL_NODE(, OID_AUTO, regression, CTLFLAG_RW, 0,
84      "Regression test MIB");
85 #endif
86 
87 SYSCTL_STRING(_kern, KERN_OSRELEASE, osrelease, CTLFLAG_RD,
88     osrelease, 0, "Operating system release");
89 
90 SYSCTL_INT(_kern, KERN_OSREV, osrevision, CTLFLAG_RD,
91     0, BSD, "Operating system revision");
92 
93 SYSCTL_STRING(_kern, KERN_VERSION, version, CTLFLAG_RD,
94     version, 0, "Kernel version");
95 
96 SYSCTL_STRING(_kern, KERN_OSTYPE, ostype, CTLFLAG_RD,
97     ostype, 0, "Operating system type");
98 
99 extern int osreldate;
100 SYSCTL_INT(_kern, KERN_OSRELDATE, osreldate, CTLFLAG_RD,
101     &osreldate, 0, "Operating system release date");
102 
103 SYSCTL_INT(_kern, KERN_MAXPROC, maxproc, CTLFLAG_RD,
104     &maxproc, 0, "Maximum number of processes");
105 
106 SYSCTL_INT(_kern, KERN_MAXPROCPERUID, maxprocperuid, CTLFLAG_RW,
107     &maxprocperuid, 0, "Maximum processes allowed per userid");
108 
109 SYSCTL_INT(_kern, OID_AUTO, maxusers, CTLFLAG_RD,
110     &maxusers, 0, "Hint for kernel tuning");
111 
112 SYSCTL_INT(_kern, KERN_ARGMAX, argmax, CTLFLAG_RD,
113     0, ARG_MAX, "Maximum bytes of argument to execve(2)");
114 
115 SYSCTL_INT(_kern, KERN_POSIX1, posix1version, CTLFLAG_RD,
116     0, _KPOSIX_VERSION, "Version of POSIX attempting to comply to");
117 
118 SYSCTL_INT(_kern, KERN_NGROUPS, ngroups, CTLFLAG_RD,
119     0, NGROUPS_MAX, "Maximum number of groups a user can belong to");
120 
121 SYSCTL_INT(_kern, KERN_JOB_CONTROL, job_control, CTLFLAG_RD,
122     0, 1, "Whether job control is available");
123 
124 #ifdef _POSIX_SAVED_IDS
125 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
126     0, 1, "Whether saved set-group/user ID is available");
127 #else
128 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
129     0, 0, "Whether saved set-group/user ID is available");
130 #endif
131 
132 char kernelname[MAXPATHLEN] = "/kernel";	/* XXX bloat */
133 
134 SYSCTL_STRING(_kern, KERN_BOOTFILE, bootfile, CTLFLAG_RW,
135     kernelname, sizeof kernelname, "Name of kernel file booted");
136 
137 #ifdef SMP
138 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
139     &mp_ncpus, 0, "Number of active CPUs");
140 #else
141 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
142     0, 1, "Number of active CPUs");
143 #endif
144 
145 SYSCTL_INT(_hw, HW_BYTEORDER, byteorder, CTLFLAG_RD,
146     0, BYTE_ORDER, "System byte order");
147 
148 SYSCTL_INT(_hw, HW_PAGESIZE, pagesize, CTLFLAG_RD,
149     0, PAGE_SIZE, "System memory page size");
150 
151 static char	machine_arch[] = MACHINE_ARCH;
152 SYSCTL_STRING(_hw, HW_MACHINE_ARCH, machine_arch, CTLFLAG_RD,
153     machine_arch, 0, "System architecture");
154 
155 char hostname[MAXHOSTNAMELEN];
156 
157 static int
158 sysctl_hostname(SYSCTL_HANDLER_ARGS)
159 {
160 	struct prison *pr;
161 	char tmphostname[MAXHOSTNAMELEN];
162 	int error;
163 
164 	pr = req->td->td_ucred->cr_prison;
165 	if (pr != NULL) {
166 		if (!jail_set_hostname_allowed && req->newptr)
167 			return (EPERM);
168 		/*
169 		 * Process is in jail, so make a local copy of jail
170 		 * hostname to get/set so we don't have to hold the jail
171 		 * mutex during the sysctl copyin/copyout activities.
172 		 */
173 		mtx_lock(&pr->pr_mtx);
174 		bcopy(pr->pr_host, tmphostname, MAXHOSTNAMELEN);
175 		mtx_unlock(&pr->pr_mtx);
176 
177 		error = sysctl_handle_string(oidp, tmphostname,
178 		    sizeof pr->pr_host, req);
179 
180 		if (req->newptr != NULL && error == 0) {
181 			/*
182 			 * Copy the locally set hostname to the jail, if
183 			 * appropriate.
184 			 */
185 			mtx_lock(&pr->pr_mtx);
186 			bcopy(tmphostname, pr->pr_host, MAXHOSTNAMELEN);
187 			mtx_unlock(&pr->pr_mtx);
188 		}
189 	} else
190 		error = sysctl_handle_string(oidp,
191 		    hostname, sizeof hostname, req);
192 	return (error);
193 }
194 
195 SYSCTL_PROC(_kern, KERN_HOSTNAME, hostname,
196        CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_PRISON,
197        0, 0, sysctl_hostname, "A", "Hostname");
198 
199 static int	regression_securelevel_nonmonotonic = 0;
200 
201 #ifdef REGRESSION
202 SYSCTL_INT(_regression, OID_AUTO, securelevel_nonmonotonic, CTLFLAG_RW,
203     &regression_securelevel_nonmonotonic, 0, "securelevel may be lowered");
204 #endif
205 
206 int securelevel = -1;
207 struct mtx securelevel_mtx;
208 
209 MTX_SYSINIT(securelevel_lock, &securelevel_mtx, "securelevel mutex lock",
210     MTX_DEF);
211 
212 static int
213 sysctl_kern_securelvl(SYSCTL_HANDLER_ARGS)
214 {
215 	struct prison *pr;
216 	int error, level;
217 
218 	pr = req->td->td_ucred->cr_prison;
219 
220 	/*
221 	 * If the process is in jail, return the maximum of the global and
222 	 * local levels; otherwise, return the global level.
223 	 */
224 	if (pr != NULL) {
225 		mtx_lock(&pr->pr_mtx);
226 		level = imax(securelevel, pr->pr_securelevel);
227 		mtx_unlock(&pr->pr_mtx);
228 	} else
229 		level = securelevel;
230 	error = sysctl_handle_int(oidp, &level, 0, req);
231 	if (error || !req->newptr)
232 		return (error);
233 	/*
234 	 * Permit update only if the new securelevel exceeds the
235 	 * global level, and local level if any.
236 	 */
237 	if (pr != NULL) {
238 		mtx_lock(&pr->pr_mtx);
239 		if (!regression_securelevel_nonmonotonic &&
240 		    (level < imax(securelevel, pr->pr_securelevel))) {
241 			mtx_unlock(&pr->pr_mtx);
242 			return (EPERM);
243 		}
244 		pr->pr_securelevel = level;
245 		mtx_unlock(&pr->pr_mtx);
246 	} else {
247 		mtx_lock(&securelevel_mtx);
248 		if (!regression_securelevel_nonmonotonic &&
249 		    (level < securelevel)) {
250 			mtx_unlock(&securelevel_mtx);
251 			return (EPERM);
252 		}
253 		securelevel = level;
254 		mtx_unlock(&securelevel_mtx);
255 	}
256 	return (error);
257 }
258 
259 SYSCTL_PROC(_kern, KERN_SECURELVL, securelevel,
260     CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, sysctl_kern_securelvl,
261     "I", "Current secure level");
262 
263 char domainname[MAXHOSTNAMELEN];
264 SYSCTL_STRING(_kern, KERN_NISDOMAINNAME, domainname, CTLFLAG_RW,
265     &domainname, sizeof(domainname), "Name of the current YP/NIS domain");
266 
267 u_long hostid;
268 SYSCTL_ULONG(_kern, KERN_HOSTID, hostid, CTLFLAG_RW, &hostid, 0, "Host ID");
269 
270 /*
271  * This is really cheating.  These actually live in the libc, something
272  * which I'm not quite sure is a good idea anyway, but in order for
273  * getnext and friends to actually work, we define dummies here.
274  */
275 SYSCTL_STRING(_user, USER_CS_PATH, cs_path, CTLFLAG_RD,
276     "", 0, "PATH that finds all the standard utilities");
277 SYSCTL_INT(_user, USER_BC_BASE_MAX, bc_base_max, CTLFLAG_RD,
278     0, 0, "Max ibase/obase values in bc(1)");
279 SYSCTL_INT(_user, USER_BC_DIM_MAX, bc_dim_max, CTLFLAG_RD,
280     0, 0, "Max array size in bc(1)");
281 SYSCTL_INT(_user, USER_BC_SCALE_MAX, bc_scale_max, CTLFLAG_RD,
282     0, 0, "Max scale value in bc(1)");
283 SYSCTL_INT(_user, USER_BC_STRING_MAX, bc_string_max, CTLFLAG_RD,
284     0, 0, "Max string length in bc(1)");
285 SYSCTL_INT(_user, USER_COLL_WEIGHTS_MAX, coll_weights_max, CTLFLAG_RD,
286     0, 0, "Maximum number of weights assigned to an LC_COLLATE locale entry");
287 SYSCTL_INT(_user, USER_EXPR_NEST_MAX, expr_nest_max, CTLFLAG_RD, 0, 0, "");
288 SYSCTL_INT(_user, USER_LINE_MAX, line_max, CTLFLAG_RD,
289     0, 0, "Max length (bytes) of a text-processing utility's input line");
290 SYSCTL_INT(_user, USER_RE_DUP_MAX, re_dup_max, CTLFLAG_RD,
291     0, 0, "Maximum number of repeats of a regexp permitted");
292 SYSCTL_INT(_user, USER_POSIX2_VERSION, posix2_version, CTLFLAG_RD,
293     0, 0,
294     "The version of POSIX 1003.2 with which the system attempts to comply");
295 SYSCTL_INT(_user, USER_POSIX2_C_BIND, posix2_c_bind, CTLFLAG_RD,
296     0, 0, "Whether C development supports the C bindings option");
297 SYSCTL_INT(_user, USER_POSIX2_C_DEV, posix2_c_dev, CTLFLAG_RD,
298     0, 0, "Whether system supports the C development utilities option");
299 SYSCTL_INT(_user, USER_POSIX2_CHAR_TERM, posix2_char_term, CTLFLAG_RD,
300     0, 0, "");
301 SYSCTL_INT(_user, USER_POSIX2_FORT_DEV, posix2_fort_dev, CTLFLAG_RD,
302     0, 0, "Whether system supports FORTRAN development utilities");
303 SYSCTL_INT(_user, USER_POSIX2_FORT_RUN, posix2_fort_run, CTLFLAG_RD,
304     0, 0, "Whether system supports FORTRAN runtime utilities");
305 SYSCTL_INT(_user, USER_POSIX2_LOCALEDEF, posix2_localedef, CTLFLAG_RD,
306     0, 0, "Whether system supports creation of locales");
307 SYSCTL_INT(_user, USER_POSIX2_SW_DEV, posix2_sw_dev, CTLFLAG_RD,
308     0, 0, "Whether system supports software development utilities");
309 SYSCTL_INT(_user, USER_POSIX2_UPE, posix2_upe, CTLFLAG_RD,
310     0, 0, "Whether system supports the user portability utilities");
311 SYSCTL_INT(_user, USER_STREAM_MAX, stream_max, CTLFLAG_RD,
312     0, 0, "Min Maximum number of streams a process may have open at one time");
313 SYSCTL_INT(_user, USER_TZNAME_MAX, tzname_max, CTLFLAG_RD,
314     0, 0, "Min Maximum number of types supported for timezone names");
315 
316 #include <sys/vnode.h>
317 SYSCTL_INT(_debug_sizeof, OID_AUTO, vnode, CTLFLAG_RD,
318     0, sizeof(struct vnode), "sizeof(struct vnode)");
319 
320 SYSCTL_INT(_debug_sizeof, OID_AUTO, proc, CTLFLAG_RD,
321     0, sizeof(struct proc), "sizeof(struct proc)");
322 
323 #include <sys/conf.h>
324 SYSCTL_INT(_debug_sizeof, OID_AUTO, specinfo, CTLFLAG_RD,
325     0, sizeof(struct specinfo), "sizeof(struct specinfo)");
326 
327 #include <sys/bio.h>
328 #include <sys/buf.h>
329 SYSCTL_INT(_debug_sizeof, OID_AUTO, bio, CTLFLAG_RD,
330     0, sizeof(struct bio), "sizeof(struct bio)");
331 SYSCTL_INT(_debug_sizeof, OID_AUTO, buf, CTLFLAG_RD,
332     0, sizeof(struct buf), "sizeof(struct buf)");
333 
334 #include <sys/user.h>
335 SYSCTL_INT(_debug_sizeof, OID_AUTO, kinfo_proc, CTLFLAG_RD,
336     0, sizeof(struct kinfo_proc), "sizeof(struct kinfo_proc)");
337