xref: /freebsd/sys/kern/kern_mib.c (revision c98323078dede7579020518ec84cdcb478e5c142)
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  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)kern_sysctl.c	8.4 (Berkeley) 4/14/94
36  */
37 
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include "opt_posix.h"
42 
43 #include <sys/param.h>
44 #include <sys/kernel.h>
45 #include <sys/systm.h>
46 #include <sys/sysctl.h>
47 #include <sys/proc.h>
48 #include <sys/lock.h>
49 #include <sys/mutex.h>
50 #include <sys/jail.h>
51 #include <sys/smp.h>
52 #include <sys/unistd.h>
53 
54 SYSCTL_NODE(, 0,	  sysctl, CTLFLAG_RW, 0,
55 	"Sysctl internal magic");
56 SYSCTL_NODE(, CTL_KERN,	  kern,   CTLFLAG_RW, 0,
57 	"High kernel, proc, limits &c");
58 SYSCTL_NODE(, CTL_VM,	  vm,     CTLFLAG_RW, 0,
59 	"Virtual memory");
60 SYSCTL_NODE(, CTL_VFS,	  vfs,     CTLFLAG_RW, 0,
61 	"File system");
62 SYSCTL_NODE(, CTL_NET,	  net,    CTLFLAG_RW, 0,
63 	"Network, (see socket.h)");
64 SYSCTL_NODE(, CTL_DEBUG,  debug,  CTLFLAG_RW, 0,
65 	"Debugging");
66 SYSCTL_NODE(_debug, OID_AUTO,  sizeof,  CTLFLAG_RW, 0,
67 	"Sizeof various things");
68 SYSCTL_NODE(, CTL_HW,	  hw,     CTLFLAG_RW, 0,
69 	"hardware");
70 SYSCTL_NODE(, CTL_MACHDEP, machdep, CTLFLAG_RW, 0,
71 	"machine dependent");
72 SYSCTL_NODE(, CTL_USER,	  user,   CTLFLAG_RW, 0,
73 	"user-level");
74 SYSCTL_NODE(, CTL_P1003_1B,  p1003_1b,   CTLFLAG_RW, 0,
75 	"p1003_1b, (see p1003_1b.h)");
76 
77 SYSCTL_NODE(, OID_AUTO,  compat, CTLFLAG_RW, 0,
78 	"Compatibility code");
79 SYSCTL_NODE(, OID_AUTO, security, CTLFLAG_RW, 0,
80      	"Security");
81 #ifdef REGRESSION
82 SYSCTL_NODE(, OID_AUTO, regression, CTLFLAG_RW, 0,
83      "Regression test MIB");
84 #endif
85 
86 SYSCTL_STRING(_kern, OID_AUTO, ident, CTLFLAG_RD,
87     kern_ident, 0, "Kernel identifier");
88 
89 SYSCTL_STRING(_kern, KERN_OSRELEASE, osrelease, CTLFLAG_RD,
90     osrelease, 0, "Operating system release");
91 
92 SYSCTL_INT(_kern, KERN_OSREV, osrevision, CTLFLAG_RD,
93     0, BSD, "Operating system revision");
94 
95 SYSCTL_STRING(_kern, KERN_VERSION, version, CTLFLAG_RD,
96     version, 0, "Kernel version");
97 
98 SYSCTL_STRING(_kern, KERN_OSTYPE, ostype, CTLFLAG_RD,
99     ostype, 0, "Operating system type");
100 
101 /*
102  * NOTICE: The *userland* release date is available in
103  * /usr/include/osreldate.h
104  */
105 extern int osreldate;
106 SYSCTL_INT(_kern, KERN_OSRELDATE, osreldate, CTLFLAG_RD,
107     &osreldate, 0, "Kernel release date");
108 
109 SYSCTL_INT(_kern, KERN_MAXPROC, maxproc, CTLFLAG_RDTUN,
110     &maxproc, 0, "Maximum number of processes");
111 
112 SYSCTL_INT(_kern, KERN_MAXPROCPERUID, maxprocperuid, CTLFLAG_RW,
113     &maxprocperuid, 0, "Maximum processes allowed per userid");
114 
115 SYSCTL_INT(_kern, OID_AUTO, maxusers, CTLFLAG_RDTUN,
116     &maxusers, 0, "Hint for kernel tuning");
117 
118 SYSCTL_INT(_kern, KERN_ARGMAX, argmax, CTLFLAG_RD,
119     0, ARG_MAX, "Maximum bytes of argument to execve(2)");
120 
121 SYSCTL_INT(_kern, KERN_POSIX1, posix1version, CTLFLAG_RD,
122     0, _POSIX_VERSION, "Version of POSIX attempting to comply to");
123 
124 SYSCTL_INT(_kern, KERN_NGROUPS, ngroups, CTLFLAG_RD,
125     0, NGROUPS_MAX, "Maximum number of groups a user can belong to");
126 
127 SYSCTL_INT(_kern, KERN_JOB_CONTROL, job_control, CTLFLAG_RD,
128     0, 1, "Whether job control is available");
129 
130 #ifdef _POSIX_SAVED_IDS
131 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
132     0, 1, "Whether saved set-group/user ID is available");
133 #else
134 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
135     0, 0, "Whether saved set-group/user ID is available");
136 #endif
137 
138 char kernelname[MAXPATHLEN] = "/kernel";	/* XXX bloat */
139 
140 SYSCTL_STRING(_kern, KERN_BOOTFILE, bootfile, CTLFLAG_RW,
141     kernelname, sizeof kernelname, "Name of kernel file booted");
142 
143 #ifdef SMP
144 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
145     &mp_ncpus, 0, "Number of active CPUs");
146 #else
147 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
148     0, 1, "Number of active CPUs");
149 #endif
150 
151 SYSCTL_INT(_hw, HW_BYTEORDER, byteorder, CTLFLAG_RD,
152     0, BYTE_ORDER, "System byte order");
153 
154 SYSCTL_INT(_hw, HW_PAGESIZE, pagesize, CTLFLAG_RD,
155     0, PAGE_SIZE, "System memory page size");
156 
157 static int
158 sysctl_hw_physmem(SYSCTL_HANDLER_ARGS)
159 {
160 	u_long val;
161 
162 	val = ctob(physmem);
163 	return (sysctl_handle_long(oidp, &val, 0, req));
164 }
165 
166 SYSCTL_PROC(_hw, HW_PHYSMEM, physmem, CTLTYPE_ULONG | CTLFLAG_RD,
167 	0, 0, sysctl_hw_physmem, "LU", "");
168 
169 static int
170 sysctl_hw_usermem(SYSCTL_HANDLER_ARGS)
171 {
172 	u_long val;
173 
174 	val = ctob(physmem - cnt.v_wire_count);
175 	return (sysctl_handle_long(oidp, &val, 0, req));
176 }
177 
178 SYSCTL_PROC(_hw, HW_USERMEM, usermem, CTLTYPE_ULONG | CTLFLAG_RD,
179 	0, 0, sysctl_hw_usermem, "LU", "");
180 
181 SYSCTL_ULONG(_hw, OID_AUTO, availpages, CTLFLAG_RD, &physmem, 0, "");
182 
183 static char	machine_arch[] = MACHINE_ARCH;
184 SYSCTL_STRING(_hw, HW_MACHINE_ARCH, machine_arch, CTLFLAG_RD,
185     machine_arch, 0, "System architecture");
186 
187 char hostname[MAXHOSTNAMELEN];
188 
189 static int
190 sysctl_hostname(SYSCTL_HANDLER_ARGS)
191 {
192 	struct prison *pr;
193 	char tmphostname[MAXHOSTNAMELEN];
194 	int error;
195 
196 	pr = req->td->td_ucred->cr_prison;
197 	if (pr != NULL) {
198 		if (!jail_set_hostname_allowed && req->newptr)
199 			return (EPERM);
200 		/*
201 		 * Process is in jail, so make a local copy of jail
202 		 * hostname to get/set so we don't have to hold the jail
203 		 * mutex during the sysctl copyin/copyout activities.
204 		 */
205 		mtx_lock(&pr->pr_mtx);
206 		bcopy(pr->pr_host, tmphostname, MAXHOSTNAMELEN);
207 		mtx_unlock(&pr->pr_mtx);
208 
209 		error = sysctl_handle_string(oidp, tmphostname,
210 		    sizeof pr->pr_host, req);
211 
212 		if (req->newptr != NULL && error == 0) {
213 			/*
214 			 * Copy the locally set hostname to the jail, if
215 			 * appropriate.
216 			 */
217 			mtx_lock(&pr->pr_mtx);
218 			bcopy(tmphostname, pr->pr_host, MAXHOSTNAMELEN);
219 			mtx_unlock(&pr->pr_mtx);
220 		}
221 	} else
222 		error = sysctl_handle_string(oidp,
223 		    hostname, sizeof hostname, req);
224 	return (error);
225 }
226 
227 SYSCTL_PROC(_kern, KERN_HOSTNAME, hostname,
228        CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_PRISON,
229        0, 0, sysctl_hostname, "A", "Hostname");
230 
231 static int	regression_securelevel_nonmonotonic = 0;
232 
233 #ifdef REGRESSION
234 SYSCTL_INT(_regression, OID_AUTO, securelevel_nonmonotonic, CTLFLAG_RW,
235     &regression_securelevel_nonmonotonic, 0, "securelevel may be lowered");
236 #endif
237 
238 int securelevel = -1;
239 static struct mtx securelevel_mtx;
240 
241 MTX_SYSINIT(securelevel_lock, &securelevel_mtx, "securelevel mutex lock",
242     MTX_DEF);
243 
244 static int
245 sysctl_kern_securelvl(SYSCTL_HANDLER_ARGS)
246 {
247 	struct prison *pr;
248 	int error, level;
249 
250 	pr = req->td->td_ucred->cr_prison;
251 
252 	/*
253 	 * If the process is in jail, return the maximum of the global and
254 	 * local levels; otherwise, return the global level.
255 	 */
256 	if (pr != NULL) {
257 		mtx_lock(&pr->pr_mtx);
258 		level = imax(securelevel, pr->pr_securelevel);
259 		mtx_unlock(&pr->pr_mtx);
260 	} else
261 		level = securelevel;
262 	error = sysctl_handle_int(oidp, &level, 0, req);
263 	if (error || !req->newptr)
264 		return (error);
265 	/*
266 	 * Permit update only if the new securelevel exceeds the
267 	 * global level, and local level if any.
268 	 */
269 	if (pr != NULL) {
270 		mtx_lock(&pr->pr_mtx);
271 		if (!regression_securelevel_nonmonotonic &&
272 		    (level < imax(securelevel, pr->pr_securelevel))) {
273 			mtx_unlock(&pr->pr_mtx);
274 			return (EPERM);
275 		}
276 		pr->pr_securelevel = level;
277 		mtx_unlock(&pr->pr_mtx);
278 	} else {
279 		mtx_lock(&securelevel_mtx);
280 		if (!regression_securelevel_nonmonotonic &&
281 		    (level < securelevel)) {
282 			mtx_unlock(&securelevel_mtx);
283 			return (EPERM);
284 		}
285 		securelevel = level;
286 		mtx_unlock(&securelevel_mtx);
287 	}
288 	return (error);
289 }
290 
291 SYSCTL_PROC(_kern, KERN_SECURELVL, securelevel,
292     CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, sysctl_kern_securelvl,
293     "I", "Current secure level");
294 
295 char domainname[MAXHOSTNAMELEN];
296 SYSCTL_STRING(_kern, KERN_NISDOMAINNAME, domainname, CTLFLAG_RW,
297     &domainname, sizeof(domainname), "Name of the current YP/NIS domain");
298 
299 u_long hostid;
300 SYSCTL_ULONG(_kern, KERN_HOSTID, hostid, CTLFLAG_RW, &hostid, 0, "Host ID");
301 
302 /*
303  * This is really cheating.  These actually live in the libc, something
304  * which I'm not quite sure is a good idea anyway, but in order for
305  * getnext and friends to actually work, we define dummies here.
306  */
307 SYSCTL_STRING(_user, USER_CS_PATH, cs_path, CTLFLAG_RD,
308     "", 0, "PATH that finds all the standard utilities");
309 SYSCTL_INT(_user, USER_BC_BASE_MAX, bc_base_max, CTLFLAG_RD,
310     0, 0, "Max ibase/obase values in bc(1)");
311 SYSCTL_INT(_user, USER_BC_DIM_MAX, bc_dim_max, CTLFLAG_RD,
312     0, 0, "Max array size in bc(1)");
313 SYSCTL_INT(_user, USER_BC_SCALE_MAX, bc_scale_max, CTLFLAG_RD,
314     0, 0, "Max scale value in bc(1)");
315 SYSCTL_INT(_user, USER_BC_STRING_MAX, bc_string_max, CTLFLAG_RD,
316     0, 0, "Max string length in bc(1)");
317 SYSCTL_INT(_user, USER_COLL_WEIGHTS_MAX, coll_weights_max, CTLFLAG_RD,
318     0, 0, "Maximum number of weights assigned to an LC_COLLATE locale entry");
319 SYSCTL_INT(_user, USER_EXPR_NEST_MAX, expr_nest_max, CTLFLAG_RD, 0, 0, "");
320 SYSCTL_INT(_user, USER_LINE_MAX, line_max, CTLFLAG_RD,
321     0, 0, "Max length (bytes) of a text-processing utility's input line");
322 SYSCTL_INT(_user, USER_RE_DUP_MAX, re_dup_max, CTLFLAG_RD,
323     0, 0, "Maximum number of repeats of a regexp permitted");
324 SYSCTL_INT(_user, USER_POSIX2_VERSION, posix2_version, CTLFLAG_RD,
325     0, 0,
326     "The version of POSIX 1003.2 with which the system attempts to comply");
327 SYSCTL_INT(_user, USER_POSIX2_C_BIND, posix2_c_bind, CTLFLAG_RD,
328     0, 0, "Whether C development supports the C bindings option");
329 SYSCTL_INT(_user, USER_POSIX2_C_DEV, posix2_c_dev, CTLFLAG_RD,
330     0, 0, "Whether system supports the C development utilities option");
331 SYSCTL_INT(_user, USER_POSIX2_CHAR_TERM, posix2_char_term, CTLFLAG_RD,
332     0, 0, "");
333 SYSCTL_INT(_user, USER_POSIX2_FORT_DEV, posix2_fort_dev, CTLFLAG_RD,
334     0, 0, "Whether system supports FORTRAN development utilities");
335 SYSCTL_INT(_user, USER_POSIX2_FORT_RUN, posix2_fort_run, CTLFLAG_RD,
336     0, 0, "Whether system supports FORTRAN runtime utilities");
337 SYSCTL_INT(_user, USER_POSIX2_LOCALEDEF, posix2_localedef, CTLFLAG_RD,
338     0, 0, "Whether system supports creation of locales");
339 SYSCTL_INT(_user, USER_POSIX2_SW_DEV, posix2_sw_dev, CTLFLAG_RD,
340     0, 0, "Whether system supports software development utilities");
341 SYSCTL_INT(_user, USER_POSIX2_UPE, posix2_upe, CTLFLAG_RD,
342     0, 0, "Whether system supports the user portability utilities");
343 SYSCTL_INT(_user, USER_STREAM_MAX, stream_max, CTLFLAG_RD,
344     0, 0, "Min Maximum number of streams a process may have open at one time");
345 SYSCTL_INT(_user, USER_TZNAME_MAX, tzname_max, CTLFLAG_RD,
346     0, 0, "Min Maximum number of types supported for timezone names");
347 
348 #include <sys/vnode.h>
349 SYSCTL_INT(_debug_sizeof, OID_AUTO, vnode, CTLFLAG_RD,
350     0, sizeof(struct vnode), "sizeof(struct vnode)");
351 
352 SYSCTL_INT(_debug_sizeof, OID_AUTO, proc, CTLFLAG_RD,
353     0, sizeof(struct proc), "sizeof(struct proc)");
354 
355 #include <sys/conf.h>
356 SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev, CTLFLAG_RD,
357     0, sizeof(struct cdev), "sizeof(struct cdev)");
358 
359 #include <sys/bio.h>
360 #include <sys/buf.h>
361 SYSCTL_INT(_debug_sizeof, OID_AUTO, bio, CTLFLAG_RD,
362     0, sizeof(struct bio), "sizeof(struct bio)");
363 SYSCTL_INT(_debug_sizeof, OID_AUTO, buf, CTLFLAG_RD,
364     0, sizeof(struct buf), "sizeof(struct buf)");
365 
366 #include <sys/user.h>
367 SYSCTL_INT(_debug_sizeof, OID_AUTO, kinfo_proc, CTLFLAG_RD,
368     0, sizeof(struct kinfo_proc), "sizeof(struct kinfo_proc)");
369 
370 /* XXX compatibility, remove for 6.0 */
371 #include <sys/imgact.h>
372 #include <sys/imgact_elf.h>
373 SYSCTL_INT(_kern, OID_AUTO, fallback_elf_brand, CTLFLAG_RW,
374     &__elfN(fallback_brand), sizeof(__elfN(fallback_brand)),
375     "compatibility for kern.fallback_elf_brand");
376