xref: /freebsd/sys/kern/kern_mib.c (revision 78704ef45793e56c8e064611c05c9bb8a0067e9f)
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 #include <sys/unistd.h>
55 
56 SYSCTL_NODE(, 0,	  sysctl, CTLFLAG_RW, 0,
57 	"Sysctl internal magic");
58 SYSCTL_NODE(, CTL_KERN,	  kern,   CTLFLAG_RW, 0,
59 	"High kernel, proc, limits &c");
60 SYSCTL_NODE(, CTL_VM,	  vm,     CTLFLAG_RW, 0,
61 	"Virtual memory");
62 SYSCTL_NODE(, CTL_VFS,	  vfs,     CTLFLAG_RW, 0,
63 	"File system");
64 SYSCTL_NODE(, CTL_NET,	  net,    CTLFLAG_RW, 0,
65 	"Network, (see socket.h)");
66 SYSCTL_NODE(, CTL_DEBUG,  debug,  CTLFLAG_RW, 0,
67 	"Debugging");
68 SYSCTL_NODE(_debug, OID_AUTO,  sizeof,  CTLFLAG_RW, 0,
69 	"Sizeof various things");
70 SYSCTL_NODE(, CTL_HW,	  hw,     CTLFLAG_RW, 0,
71 	"hardware");
72 SYSCTL_NODE(, CTL_MACHDEP, machdep, CTLFLAG_RW, 0,
73 	"machine dependent");
74 SYSCTL_NODE(, CTL_USER,	  user,   CTLFLAG_RW, 0,
75 	"user-level");
76 SYSCTL_NODE(, CTL_P1003_1B,  p1003_1b,   CTLFLAG_RW, 0,
77 	"p1003_1b, (see p1003_1b.h)");
78 
79 SYSCTL_NODE(, OID_AUTO,  compat, CTLFLAG_RW, 0,
80 	"Compatibility code");
81 SYSCTL_NODE(, OID_AUTO, security, CTLFLAG_RW, 0,
82      	"Security");
83 #ifdef REGRESSION
84 SYSCTL_NODE(, OID_AUTO, regression, CTLFLAG_RW, 0,
85      "Regression test MIB");
86 #endif
87 
88 SYSCTL_STRING(_kern, KERN_OSRELEASE, osrelease, CTLFLAG_RD,
89     osrelease, 0, "Operating system release");
90 
91 SYSCTL_INT(_kern, KERN_OSREV, osrevision, CTLFLAG_RD,
92     0, BSD, "Operating system revision");
93 
94 SYSCTL_STRING(_kern, KERN_VERSION, version, CTLFLAG_RD,
95     version, 0, "Kernel version");
96 
97 SYSCTL_STRING(_kern, KERN_OSTYPE, ostype, CTLFLAG_RD,
98     ostype, 0, "Operating system type");
99 
100 extern int osreldate;
101 SYSCTL_INT(_kern, KERN_OSRELDATE, osreldate, CTLFLAG_RD,
102     &osreldate, 0, "Operating system release date");
103 
104 SYSCTL_INT(_kern, KERN_MAXPROC, maxproc, CTLFLAG_RD,
105     &maxproc, 0, "Maximum number of processes");
106 
107 SYSCTL_INT(_kern, KERN_MAXPROCPERUID, maxprocperuid, CTLFLAG_RW,
108     &maxprocperuid, 0, "Maximum processes allowed per userid");
109 
110 SYSCTL_INT(_kern, OID_AUTO, maxusers, CTLFLAG_RD,
111     &maxusers, 0, "Hint for kernel tuning");
112 
113 SYSCTL_INT(_kern, KERN_ARGMAX, argmax, CTLFLAG_RD,
114     0, ARG_MAX, "Maximum bytes of argument to execve(2)");
115 
116 SYSCTL_INT(_kern, KERN_POSIX1, posix1version, CTLFLAG_RD,
117     0, _POSIX_VERSION, "Version of POSIX attempting to comply to");
118 
119 SYSCTL_INT(_kern, KERN_NGROUPS, ngroups, CTLFLAG_RD,
120     0, NGROUPS_MAX, "Maximum number of groups a user can belong to");
121 
122 SYSCTL_INT(_kern, KERN_JOB_CONTROL, job_control, CTLFLAG_RD,
123     0, 1, "Whether job control is available");
124 
125 #ifdef _POSIX_SAVED_IDS
126 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
127     0, 1, "Whether saved set-group/user ID is available");
128 #else
129 SYSCTL_INT(_kern, KERN_SAVED_IDS, saved_ids, CTLFLAG_RD,
130     0, 0, "Whether saved set-group/user ID is available");
131 #endif
132 
133 char kernelname[MAXPATHLEN] = "/kernel";	/* XXX bloat */
134 
135 SYSCTL_STRING(_kern, KERN_BOOTFILE, bootfile, CTLFLAG_RW,
136     kernelname, sizeof kernelname, "Name of kernel file booted");
137 
138 #ifdef SMP
139 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
140     &mp_ncpus, 0, "Number of active CPUs");
141 #else
142 SYSCTL_INT(_hw, HW_NCPU, ncpu, CTLFLAG_RD,
143     0, 1, "Number of active CPUs");
144 #endif
145 
146 SYSCTL_INT(_hw, HW_BYTEORDER, byteorder, CTLFLAG_RD,
147     0, BYTE_ORDER, "System byte order");
148 
149 SYSCTL_INT(_hw, HW_PAGESIZE, pagesize, CTLFLAG_RD,
150     0, PAGE_SIZE, "System memory page size");
151 
152 static char	machine_arch[] = MACHINE_ARCH;
153 SYSCTL_STRING(_hw, HW_MACHINE_ARCH, machine_arch, CTLFLAG_RD,
154     machine_arch, 0, "System architecture");
155 
156 char hostname[MAXHOSTNAMELEN];
157 
158 static int
159 sysctl_hostname(SYSCTL_HANDLER_ARGS)
160 {
161 	struct prison *pr;
162 	char tmphostname[MAXHOSTNAMELEN];
163 	int error;
164 
165 	pr = req->td->td_ucred->cr_prison;
166 	if (pr != NULL) {
167 		if (!jail_set_hostname_allowed && req->newptr)
168 			return (EPERM);
169 		/*
170 		 * Process is in jail, so make a local copy of jail
171 		 * hostname to get/set so we don't have to hold the jail
172 		 * mutex during the sysctl copyin/copyout activities.
173 		 */
174 		mtx_lock(&pr->pr_mtx);
175 		bcopy(pr->pr_host, tmphostname, MAXHOSTNAMELEN);
176 		mtx_unlock(&pr->pr_mtx);
177 
178 		error = sysctl_handle_string(oidp, tmphostname,
179 		    sizeof pr->pr_host, req);
180 
181 		if (req->newptr != NULL && error == 0) {
182 			/*
183 			 * Copy the locally set hostname to the jail, if
184 			 * appropriate.
185 			 */
186 			mtx_lock(&pr->pr_mtx);
187 			bcopy(tmphostname, pr->pr_host, MAXHOSTNAMELEN);
188 			mtx_unlock(&pr->pr_mtx);
189 		}
190 	} else
191 		error = sysctl_handle_string(oidp,
192 		    hostname, sizeof hostname, req);
193 	return (error);
194 }
195 
196 SYSCTL_PROC(_kern, KERN_HOSTNAME, hostname,
197        CTLTYPE_STRING|CTLFLAG_RW|CTLFLAG_PRISON,
198        0, 0, sysctl_hostname, "A", "Hostname");
199 
200 static int	regression_securelevel_nonmonotonic = 0;
201 
202 #ifdef REGRESSION
203 SYSCTL_INT(_regression, OID_AUTO, securelevel_nonmonotonic, CTLFLAG_RW,
204     &regression_securelevel_nonmonotonic, 0, "securelevel may be lowered");
205 #endif
206 
207 int securelevel = -1;
208 struct mtx securelevel_mtx;
209 
210 MTX_SYSINIT(securelevel_lock, &securelevel_mtx, "securelevel mutex lock",
211     MTX_DEF);
212 
213 static int
214 sysctl_kern_securelvl(SYSCTL_HANDLER_ARGS)
215 {
216 	struct prison *pr;
217 	int error, level;
218 
219 	pr = req->td->td_ucred->cr_prison;
220 
221 	/*
222 	 * If the process is in jail, return the maximum of the global and
223 	 * local levels; otherwise, return the global level.
224 	 */
225 	if (pr != NULL) {
226 		mtx_lock(&pr->pr_mtx);
227 		level = imax(securelevel, pr->pr_securelevel);
228 		mtx_unlock(&pr->pr_mtx);
229 	} else
230 		level = securelevel;
231 	error = sysctl_handle_int(oidp, &level, 0, req);
232 	if (error || !req->newptr)
233 		return (error);
234 	/*
235 	 * Permit update only if the new securelevel exceeds the
236 	 * global level, and local level if any.
237 	 */
238 	if (pr != NULL) {
239 		mtx_lock(&pr->pr_mtx);
240 		if (!regression_securelevel_nonmonotonic &&
241 		    (level < imax(securelevel, pr->pr_securelevel))) {
242 			mtx_unlock(&pr->pr_mtx);
243 			return (EPERM);
244 		}
245 		pr->pr_securelevel = level;
246 		mtx_unlock(&pr->pr_mtx);
247 	} else {
248 		mtx_lock(&securelevel_mtx);
249 		if (!regression_securelevel_nonmonotonic &&
250 		    (level < securelevel)) {
251 			mtx_unlock(&securelevel_mtx);
252 			return (EPERM);
253 		}
254 		securelevel = level;
255 		mtx_unlock(&securelevel_mtx);
256 	}
257 	return (error);
258 }
259 
260 SYSCTL_PROC(_kern, KERN_SECURELVL, securelevel,
261     CTLTYPE_INT|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0, sysctl_kern_securelvl,
262     "I", "Current secure level");
263 
264 char domainname[MAXHOSTNAMELEN];
265 SYSCTL_STRING(_kern, KERN_NISDOMAINNAME, domainname, CTLFLAG_RW,
266     &domainname, sizeof(domainname), "Name of the current YP/NIS domain");
267 
268 u_long hostid;
269 SYSCTL_ULONG(_kern, KERN_HOSTID, hostid, CTLFLAG_RW, &hostid, 0, "Host ID");
270 
271 /*
272  * This is really cheating.  These actually live in the libc, something
273  * which I'm not quite sure is a good idea anyway, but in order for
274  * getnext and friends to actually work, we define dummies here.
275  */
276 SYSCTL_STRING(_user, USER_CS_PATH, cs_path, CTLFLAG_RD,
277     "", 0, "PATH that finds all the standard utilities");
278 SYSCTL_INT(_user, USER_BC_BASE_MAX, bc_base_max, CTLFLAG_RD,
279     0, 0, "Max ibase/obase values in bc(1)");
280 SYSCTL_INT(_user, USER_BC_DIM_MAX, bc_dim_max, CTLFLAG_RD,
281     0, 0, "Max array size in bc(1)");
282 SYSCTL_INT(_user, USER_BC_SCALE_MAX, bc_scale_max, CTLFLAG_RD,
283     0, 0, "Max scale value in bc(1)");
284 SYSCTL_INT(_user, USER_BC_STRING_MAX, bc_string_max, CTLFLAG_RD,
285     0, 0, "Max string length in bc(1)");
286 SYSCTL_INT(_user, USER_COLL_WEIGHTS_MAX, coll_weights_max, CTLFLAG_RD,
287     0, 0, "Maximum number of weights assigned to an LC_COLLATE locale entry");
288 SYSCTL_INT(_user, USER_EXPR_NEST_MAX, expr_nest_max, CTLFLAG_RD, 0, 0, "");
289 SYSCTL_INT(_user, USER_LINE_MAX, line_max, CTLFLAG_RD,
290     0, 0, "Max length (bytes) of a text-processing utility's input line");
291 SYSCTL_INT(_user, USER_RE_DUP_MAX, re_dup_max, CTLFLAG_RD,
292     0, 0, "Maximum number of repeats of a regexp permitted");
293 SYSCTL_INT(_user, USER_POSIX2_VERSION, posix2_version, CTLFLAG_RD,
294     0, 0,
295     "The version of POSIX 1003.2 with which the system attempts to comply");
296 SYSCTL_INT(_user, USER_POSIX2_C_BIND, posix2_c_bind, CTLFLAG_RD,
297     0, 0, "Whether C development supports the C bindings option");
298 SYSCTL_INT(_user, USER_POSIX2_C_DEV, posix2_c_dev, CTLFLAG_RD,
299     0, 0, "Whether system supports the C development utilities option");
300 SYSCTL_INT(_user, USER_POSIX2_CHAR_TERM, posix2_char_term, CTLFLAG_RD,
301     0, 0, "");
302 SYSCTL_INT(_user, USER_POSIX2_FORT_DEV, posix2_fort_dev, CTLFLAG_RD,
303     0, 0, "Whether system supports FORTRAN development utilities");
304 SYSCTL_INT(_user, USER_POSIX2_FORT_RUN, posix2_fort_run, CTLFLAG_RD,
305     0, 0, "Whether system supports FORTRAN runtime utilities");
306 SYSCTL_INT(_user, USER_POSIX2_LOCALEDEF, posix2_localedef, CTLFLAG_RD,
307     0, 0, "Whether system supports creation of locales");
308 SYSCTL_INT(_user, USER_POSIX2_SW_DEV, posix2_sw_dev, CTLFLAG_RD,
309     0, 0, "Whether system supports software development utilities");
310 SYSCTL_INT(_user, USER_POSIX2_UPE, posix2_upe, CTLFLAG_RD,
311     0, 0, "Whether system supports the user portability utilities");
312 SYSCTL_INT(_user, USER_STREAM_MAX, stream_max, CTLFLAG_RD,
313     0, 0, "Min Maximum number of streams a process may have open at one time");
314 SYSCTL_INT(_user, USER_TZNAME_MAX, tzname_max, CTLFLAG_RD,
315     0, 0, "Min Maximum number of types supported for timezone names");
316 
317 #include <sys/vnode.h>
318 SYSCTL_INT(_debug_sizeof, OID_AUTO, vnode, CTLFLAG_RD,
319     0, sizeof(struct vnode), "sizeof(struct vnode)");
320 
321 SYSCTL_INT(_debug_sizeof, OID_AUTO, proc, CTLFLAG_RD,
322     0, sizeof(struct proc), "sizeof(struct proc)");
323 
324 #include <sys/conf.h>
325 SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev, CTLFLAG_RD,
326     0, sizeof(struct cdev), "sizeof(struct cdev)");
327 
328 #include <sys/bio.h>
329 #include <sys/buf.h>
330 SYSCTL_INT(_debug_sizeof, OID_AUTO, bio, CTLFLAG_RD,
331     0, sizeof(struct bio), "sizeof(struct bio)");
332 SYSCTL_INT(_debug_sizeof, OID_AUTO, buf, CTLFLAG_RD,
333     0, sizeof(struct buf), "sizeof(struct buf)");
334 
335 #include <sys/user.h>
336 SYSCTL_INT(_debug_sizeof, OID_AUTO, kinfo_proc, CTLFLAG_RD,
337     0, sizeof(struct kinfo_proc), "sizeof(struct kinfo_proc)");
338