xref: /freebsd/sys/kern/kern_mib.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
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  */
41 
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44 
45 #include "opt_posix.h"
46 
47 #include <sys/param.h>
48 #include <sys/kernel.h>
49 #include <sys/systm.h>
50 #include <sys/sysctl.h>
51 #include <sys/proc.h>
52 #include <sys/lock.h>
53 #include <sys/mutex.h>
54 #include <sys/jail.h>
55 #include <sys/smp.h>
56 #include <sys/unistd.h>
57 
58 SYSCTL_NODE(, 0,	  sysctl, CTLFLAG_RW, 0,
59 	"Sysctl internal magic");
60 SYSCTL_NODE(, CTL_KERN,	  kern,   CTLFLAG_RW, 0,
61 	"High kernel, proc, limits &c");
62 SYSCTL_NODE(, CTL_VM,	  vm,     CTLFLAG_RW, 0,
63 	"Virtual memory");
64 SYSCTL_NODE(, CTL_VFS,	  vfs,     CTLFLAG_RW, 0,
65 	"File system");
66 SYSCTL_NODE(, CTL_NET,	  net,    CTLFLAG_RW, 0,
67 	"Network, (see socket.h)");
68 SYSCTL_NODE(, CTL_DEBUG,  debug,  CTLFLAG_RW, 0,
69 	"Debugging");
70 SYSCTL_NODE(_debug, OID_AUTO,  sizeof,  CTLFLAG_RW, 0,
71 	"Sizeof various things");
72 SYSCTL_NODE(, CTL_HW,	  hw,     CTLFLAG_RW, 0,
73 	"hardware");
74 SYSCTL_NODE(, CTL_MACHDEP, machdep, CTLFLAG_RW, 0,
75 	"machine dependent");
76 SYSCTL_NODE(, CTL_USER,	  user,   CTLFLAG_RW, 0,
77 	"user-level");
78 SYSCTL_NODE(, CTL_P1003_1B,  p1003_1b,   CTLFLAG_RW, 0,
79 	"p1003_1b, (see p1003_1b.h)");
80 
81 SYSCTL_NODE(, OID_AUTO,  compat, CTLFLAG_RW, 0,
82 	"Compatibility code");
83 SYSCTL_NODE(, OID_AUTO, security, CTLFLAG_RW, 0,
84      	"Security");
85 #ifdef REGRESSION
86 SYSCTL_NODE(, OID_AUTO, regression, CTLFLAG_RW, 0,
87      "Regression test MIB");
88 #endif
89 
90 SYSCTL_STRING(_kern, OID_AUTO, ident, CTLFLAG_RD,
91     kern_ident, 0, "Kernel identifier");
92 
93 SYSCTL_STRING(_kern, KERN_OSRELEASE, osrelease, CTLFLAG_RD,
94     osrelease, 0, "Operating system release");
95 
96 SYSCTL_INT(_kern, KERN_OSREV, osrevision, CTLFLAG_RD,
97     0, BSD, "Operating system revision");
98 
99 SYSCTL_STRING(_kern, KERN_VERSION, version, CTLFLAG_RD,
100     version, 0, "Kernel version");
101 
102 SYSCTL_STRING(_kern, KERN_OSTYPE, ostype, CTLFLAG_RD,
103     ostype, 0, "Operating system type");
104 
105 /*
106  * NOTICE: The *userland* release date is available in
107  * /usr/include/osreldate.h
108  */
109 extern int osreldate;
110 SYSCTL_INT(_kern, KERN_OSRELDATE, osreldate, CTLFLAG_RD,
111     &osreldate, 0, "Kernel release date");
112 
113 SYSCTL_INT(_kern, KERN_MAXPROC, maxproc, CTLFLAG_RD,
114     &maxproc, 0, "Maximum number of processes");
115 
116 SYSCTL_INT(_kern, KERN_MAXPROCPERUID, maxprocperuid, CTLFLAG_RW,
117     &maxprocperuid, 0, "Maximum processes allowed per userid");
118 
119 SYSCTL_INT(_kern, OID_AUTO, maxusers, CTLFLAG_RD,
120     &maxusers, 0, "Hint for kernel tuning");
121 
122 SYSCTL_INT(_kern, KERN_ARGMAX, argmax, CTLFLAG_RD,
123     0, ARG_MAX, "Maximum bytes of argument to execve(2)");
124 
125 SYSCTL_INT(_kern, KERN_POSIX1, posix1version, CTLFLAG_RD,
126     0, _POSIX_VERSION, "Version of POSIX attempting to comply to");
127 
128 SYSCTL_INT(_kern, KERN_NGROUPS, ngroups, CTLFLAG_RD,
129     0, NGROUPS_MAX, "Maximum number of groups a user can belong to");
130 
131 SYSCTL_INT(_kern, KERN_JOB_CONTROL, job_control, CTLFLAG_RD,
132     0, 1, "Whether job control is available");
133 
134 #ifdef _POSIX_SAVED_IDS
135 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
136     0, 1, "Whether saved set-group/user ID is available");
137 #else
138 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
139     0, 0, "Whether saved set-group/user ID is available");
140 #endif
141 
142 char kernelname[MAXPATHLEN] = "/kernel";	/* XXX bloat */
143 
144 SYSCTL_STRING(_kern, KERN_BOOTFILE, bootfile, CTLFLAG_RW,
145     kernelname, sizeof kernelname, "Name of kernel file booted");
146 
147 #ifdef SMP
148 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
149     &mp_ncpus, 0, "Number of active CPUs");
150 #else
151 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
152     0, 1, "Number of active CPUs");
153 #endif
154 
155 SYSCTL_INT(_hw, HW_BYTEORDER, byteorder, CTLFLAG_RD,
156     0, BYTE_ORDER, "System byte order");
157 
158 SYSCTL_INT(_hw, HW_PAGESIZE, pagesize, CTLFLAG_RD,
159     0, PAGE_SIZE, "System memory page size");
160 
161 static int
162 sysctl_hw_physmem(SYSCTL_HANDLER_ARGS)
163 {
164 	u_long val;
165 
166 	val = ctob(physmem);
167 	return (sysctl_handle_long(oidp, &val, 0, req));
168 }
169 
170 SYSCTL_PROC(_hw, HW_PHYSMEM, physmem, CTLTYPE_ULONG | CTLFLAG_RD,
171 	0, 0, sysctl_hw_physmem, "LU", "");
172 
173 static int
174 sysctl_hw_usermem(SYSCTL_HANDLER_ARGS)
175 {
176 	u_long val;
177 
178 	val = ctob(physmem - cnt.v_wire_count);
179 	return (sysctl_handle_long(oidp, &val, 0, req));
180 }
181 
182 SYSCTL_PROC(_hw, HW_USERMEM, usermem, CTLTYPE_ULONG | CTLFLAG_RD,
183 	0, 0, sysctl_hw_usermem, "LU", "");
184 
185 SYSCTL_ULONG(_hw, OID_AUTO, availpages, CTLFLAG_RD, &physmem, 0, "");
186 
187 static char	machine_arch[] = MACHINE_ARCH;
188 SYSCTL_STRING(_hw, HW_MACHINE_ARCH, machine_arch, CTLFLAG_RD,
189     machine_arch, 0, "System architecture");
190 
191 char hostname[MAXHOSTNAMELEN];
192 
193 static int
194 sysctl_hostname(SYSCTL_HANDLER_ARGS)
195 {
196 	struct prison *pr;
197 	char tmphostname[MAXHOSTNAMELEN];
198 	int error;
199 
200 	pr = req->td->td_ucred->cr_prison;
201 	if (pr != NULL) {
202 		if (!jail_set_hostname_allowed && req->newptr)
203 			return (EPERM);
204 		/*
205 		 * Process is in jail, so make a local copy of jail
206 		 * hostname to get/set so we don't have to hold the jail
207 		 * mutex during the sysctl copyin/copyout activities.
208 		 */
209 		mtx_lock(&pr->pr_mtx);
210 		bcopy(pr->pr_host, tmphostname, MAXHOSTNAMELEN);
211 		mtx_unlock(&pr->pr_mtx);
212 
213 		error = sysctl_handle_string(oidp, tmphostname,
214 		    sizeof pr->pr_host, req);
215 
216 		if (req->newptr != NULL && error == 0) {
217 			/*
218 			 * Copy the locally set hostname to the jail, if
219 			 * appropriate.
220 			 */
221 			mtx_lock(&pr->pr_mtx);
222 			bcopy(tmphostname, pr->pr_host, MAXHOSTNAMELEN);
223 			mtx_unlock(&pr->pr_mtx);
224 		}
225 	} else
226 		error = sysctl_handle_string(oidp,
227 		    hostname, sizeof hostname, req);
228 	return (error);
229 }
230 
231 SYSCTL_PROC(_kern, KERN_HOSTNAME, hostname,
232        CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_PRISON,
233        0, 0, sysctl_hostname, "A", "Hostname");
234 
235 static int	regression_securelevel_nonmonotonic = 0;
236 
237 #ifdef REGRESSION
238 SYSCTL_INT(_regression, OID_AUTO, securelevel_nonmonotonic, CTLFLAG_RW,
239     &regression_securelevel_nonmonotonic, 0, "securelevel may be lowered");
240 #endif
241 
242 int securelevel = -1;
243 static struct mtx securelevel_mtx;
244 
245 MTX_SYSINIT(securelevel_lock, &securelevel_mtx, "securelevel mutex lock",
246     MTX_DEF);
247 
248 static int
249 sysctl_kern_securelvl(SYSCTL_HANDLER_ARGS)
250 {
251 	struct prison *pr;
252 	int error, level;
253 
254 	pr = req->td->td_ucred->cr_prison;
255 
256 	/*
257 	 * If the process is in jail, return the maximum of the global and
258 	 * local levels; otherwise, return the global level.
259 	 */
260 	if (pr != NULL) {
261 		mtx_lock(&pr->pr_mtx);
262 		level = imax(securelevel, pr->pr_securelevel);
263 		mtx_unlock(&pr->pr_mtx);
264 	} else
265 		level = securelevel;
266 	error = sysctl_handle_int(oidp, &level, 0, req);
267 	if (error || !req->newptr)
268 		return (error);
269 	/*
270 	 * Permit update only if the new securelevel exceeds the
271 	 * global level, and local level if any.
272 	 */
273 	if (pr != NULL) {
274 		mtx_lock(&pr->pr_mtx);
275 		if (!regression_securelevel_nonmonotonic &&
276 		    (level < imax(securelevel, pr->pr_securelevel))) {
277 			mtx_unlock(&pr->pr_mtx);
278 			return (EPERM);
279 		}
280 		pr->pr_securelevel = level;
281 		mtx_unlock(&pr->pr_mtx);
282 	} else {
283 		mtx_lock(&securelevel_mtx);
284 		if (!regression_securelevel_nonmonotonic &&
285 		    (level < securelevel)) {
286 			mtx_unlock(&securelevel_mtx);
287 			return (EPERM);
288 		}
289 		securelevel = level;
290 		mtx_unlock(&securelevel_mtx);
291 	}
292 	return (error);
293 }
294 
295 SYSCTL_PROC(_kern, KERN_SECURELVL, securelevel,
296     CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, sysctl_kern_securelvl,
297     "I", "Current secure level");
298 
299 char domainname[MAXHOSTNAMELEN];
300 SYSCTL_STRING(_kern, KERN_NISDOMAINNAME, domainname, CTLFLAG_RW,
301     &domainname, sizeof(domainname), "Name of the current YP/NIS domain");
302 
303 u_long hostid;
304 SYSCTL_ULONG(_kern, KERN_HOSTID, hostid, CTLFLAG_RW, &hostid, 0, "Host ID");
305 
306 /*
307  * This is really cheating.  These actually live in the libc, something
308  * which I'm not quite sure is a good idea anyway, but in order for
309  * getnext and friends to actually work, we define dummies here.
310  */
311 SYSCTL_STRING(_user, USER_CS_PATH, cs_path, CTLFLAG_RD,
312     "", 0, "PATH that finds all the standard utilities");
313 SYSCTL_INT(_user, USER_BC_BASE_MAX, bc_base_max, CTLFLAG_RD,
314     0, 0, "Max ibase/obase values in bc(1)");
315 SYSCTL_INT(_user, USER_BC_DIM_MAX, bc_dim_max, CTLFLAG_RD,
316     0, 0, "Max array size in bc(1)");
317 SYSCTL_INT(_user, USER_BC_SCALE_MAX, bc_scale_max, CTLFLAG_RD,
318     0, 0, "Max scale value in bc(1)");
319 SYSCTL_INT(_user, USER_BC_STRING_MAX, bc_string_max, CTLFLAG_RD,
320     0, 0, "Max string length in bc(1)");
321 SYSCTL_INT(_user, USER_COLL_WEIGHTS_MAX, coll_weights_max, CTLFLAG_RD,
322     0, 0, "Maximum number of weights assigned to an LC_COLLATE locale entry");
323 SYSCTL_INT(_user, USER_EXPR_NEST_MAX, expr_nest_max, CTLFLAG_RD, 0, 0, "");
324 SYSCTL_INT(_user, USER_LINE_MAX, line_max, CTLFLAG_RD,
325     0, 0, "Max length (bytes) of a text-processing utility's input line");
326 SYSCTL_INT(_user, USER_RE_DUP_MAX, re_dup_max, CTLFLAG_RD,
327     0, 0, "Maximum number of repeats of a regexp permitted");
328 SYSCTL_INT(_user, USER_POSIX2_VERSION, posix2_version, CTLFLAG_RD,
329     0, 0,
330     "The version of POSIX 1003.2 with which the system attempts to comply");
331 SYSCTL_INT(_user, USER_POSIX2_C_BIND, posix2_c_bind, CTLFLAG_RD,
332     0, 0, "Whether C development supports the C bindings option");
333 SYSCTL_INT(_user, USER_POSIX2_C_DEV, posix2_c_dev, CTLFLAG_RD,
334     0, 0, "Whether system supports the C development utilities option");
335 SYSCTL_INT(_user, USER_POSIX2_CHAR_TERM, posix2_char_term, CTLFLAG_RD,
336     0, 0, "");
337 SYSCTL_INT(_user, USER_POSIX2_FORT_DEV, posix2_fort_dev, CTLFLAG_RD,
338     0, 0, "Whether system supports FORTRAN development utilities");
339 SYSCTL_INT(_user, USER_POSIX2_FORT_RUN, posix2_fort_run, CTLFLAG_RD,
340     0, 0, "Whether system supports FORTRAN runtime utilities");
341 SYSCTL_INT(_user, USER_POSIX2_LOCALEDEF, posix2_localedef, CTLFLAG_RD,
342     0, 0, "Whether system supports creation of locales");
343 SYSCTL_INT(_user, USER_POSIX2_SW_DEV, posix2_sw_dev, CTLFLAG_RD,
344     0, 0, "Whether system supports software development utilities");
345 SYSCTL_INT(_user, USER_POSIX2_UPE, posix2_upe, CTLFLAG_RD,
346     0, 0, "Whether system supports the user portability utilities");
347 SYSCTL_INT(_user, USER_STREAM_MAX, stream_max, CTLFLAG_RD,
348     0, 0, "Min Maximum number of streams a process may have open at one time");
349 SYSCTL_INT(_user, USER_TZNAME_MAX, tzname_max, CTLFLAG_RD,
350     0, 0, "Min Maximum number of types supported for timezone names");
351 
352 #include <sys/vnode.h>
353 SYSCTL_INT(_debug_sizeof, OID_AUTO, vnode, CTLFLAG_RD,
354     0, sizeof(struct vnode), "sizeof(struct vnode)");
355 
356 SYSCTL_INT(_debug_sizeof, OID_AUTO, proc, CTLFLAG_RD,
357     0, sizeof(struct proc), "sizeof(struct proc)");
358 
359 #include <sys/conf.h>
360 SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev, CTLFLAG_RD,
361     0, sizeof(struct cdev), "sizeof(struct cdev)");
362 
363 #include <sys/bio.h>
364 #include <sys/buf.h>
365 SYSCTL_INT(_debug_sizeof, OID_AUTO, bio, CTLFLAG_RD,
366     0, sizeof(struct bio), "sizeof(struct bio)");
367 SYSCTL_INT(_debug_sizeof, OID_AUTO, buf, CTLFLAG_RD,
368     0, sizeof(struct buf), "sizeof(struct buf)");
369 
370 #include <sys/user.h>
371 SYSCTL_INT(_debug_sizeof, OID_AUTO, kinfo_proc, CTLFLAG_RD,
372     0, sizeof(struct kinfo_proc), "sizeof(struct kinfo_proc)");
373 
374 /* XXX compatibility, remove for 6.0 */
375 #include <sys/imgact.h>
376 #include <sys/imgact_elf.h>
377 SYSCTL_INT(_kern, OID_AUTO, fallback_elf_brand, CTLFLAG_RW,
378     &__elfN(fallback_brand), sizeof(__elfN(fallback_brand)),
379     "compatibility for kern.fallback_elf_brand");
380