xref: /freebsd/sbin/sysctl/sysctl.c (revision d2387d42b8da231a5b95cbc313825fb2aadf26f6)
1 /*
2  * Copyright (c) 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)from: sysctl.c	8.1 (Berkeley) 6/6/93";
43 #endif
44 static const char rcsid[] =
45   "$FreeBSD$";
46 #endif /* not lint */
47 
48 #ifdef __i386__
49 #include <sys/reboot.h>		/* used for bootdev parsing */
50 #endif
51 #include <sys/param.h>
52 #include <sys/time.h>
53 #include <sys/resource.h>
54 #include <sys/stat.h>
55 #include <sys/sysctl.h>
56 #include <sys/vmmeter.h>
57 
58 #include <ctype.h>
59 #include <err.h>
60 #include <errno.h>
61 #include <locale.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #include <unistd.h>
66 
67 static int	aflag, bflag, dflag, eflag, hflag, Nflag, nflag, oflag, xflag;
68 
69 static int	oidfmt(int *, int, char *, u_int *);
70 static void	parse(char *);
71 static int	show_var(int *, int);
72 static int	sysctl_all (int *oid, int len);
73 static int	name2oid(char *, int *);
74 
75 static void	set_T_dev_t (char *, void **, size_t *);
76 
77 static void
78 usage(void)
79 {
80 
81 	(void)fprintf(stderr, "%s\n%s\n",
82 	    "usage: sysctl [-bdehNnox] variable[=value] ...",
83 	    "       sysctl [-bdehNnox] -a");
84 	exit(1);
85 }
86 
87 int
88 main(int argc, char **argv)
89 {
90 	int ch;
91 
92 	setlocale(LC_NUMERIC, "");
93 	setbuf(stdout,0);
94 	setbuf(stderr,0);
95 
96 	while ((ch = getopt(argc, argv, "AabdehNnowxX")) != -1) {
97 		switch (ch) {
98 		case 'A':
99 			/* compatibility */
100 			aflag = oflag = 1;
101 			break;
102 		case 'a':
103 			aflag = 1;
104 			break;
105 		case 'b':
106 			bflag = 1;
107 			break;
108 		case 'd':
109 			dflag = 1;
110 			break;
111 		case 'e':
112 			eflag = 1;
113 			break;
114 		case 'h':
115 			hflag = 1;
116 			break;
117 		case 'N':
118 			Nflag = 1;
119 			break;
120 		case 'n':
121 			nflag = 1;
122 			break;
123 		case 'o':
124 			oflag = 1;
125 			break;
126 		case 'w':
127 			/* compatibility */
128 			/* ignored */
129 			break;
130 		case 'X':
131 			/* compatibility */
132 			aflag = xflag = 1;
133 			break;
134 		case 'x':
135 			xflag = 1;
136 			break;
137 		default:
138 			usage();
139 		}
140 	}
141 	argc -= optind;
142 	argv += optind;
143 
144 	if (Nflag && nflag)
145 		usage();
146 	if (aflag && argc == 0)
147 		exit(sysctl_all(0, 0));
148 	if (argc == 0)
149 		usage();
150 	while (argc-- > 0)
151 		parse(*argv++);
152 	exit(0);
153 }
154 
155 /*
156  * Parse a name into a MIB entry.
157  * Lookup and print out the MIB entry if it exists.
158  * Set a new value if requested.
159  */
160 static void
161 parse(char *string)
162 {
163 	int len, i, j;
164 	void *newval = 0;
165 	int intval;
166 	unsigned int uintval;
167 	long longval;
168 	unsigned long ulongval;
169 	size_t newsize = 0;
170 	quad_t quadval;
171 	int mib[CTL_MAXNAME];
172 	char *cp, *bufp, buf[BUFSIZ], *endptr, fmt[BUFSIZ];
173 	u_int kind;
174 
175 	bufp = buf;
176 	snprintf(buf, BUFSIZ, "%s", string);
177 	if ((cp = strchr(string, '=')) != NULL) {
178 		*strchr(buf, '=') = '\0';
179 		*cp++ = '\0';
180 		while (isspace(*cp))
181 			cp++;
182 		newval = cp;
183 		newsize = strlen(cp);
184 	}
185 	len = name2oid(bufp, mib);
186 
187 	if (len < 0)
188 		errx(1, "unknown oid '%s'", bufp);
189 
190 	if (oidfmt(mib, len, fmt, &kind))
191 		err(1, "couldn't find format of oid '%s'", bufp);
192 
193 	if (newval == NULL) {
194 		if ((kind & CTLTYPE) == CTLTYPE_NODE) {
195 			sysctl_all(mib, len);
196 		} else {
197 			i = show_var(mib, len);
198 			if (!i && !bflag)
199 				putchar('\n');
200 		}
201 	} else {
202 		if ((kind & CTLTYPE) == CTLTYPE_NODE)
203 			errx(1, "oid '%s' isn't a leaf node", bufp);
204 
205 		if (!(kind & CTLFLAG_WR)) {
206 			if (kind & CTLFLAG_TUN) {
207 				warnx("oid '%s' is a read only tunable", bufp);
208 				errx(1, "Tunable values are set in /boot/loader.conf");
209 			} else {
210 				errx(1, "oid '%s' is read only", bufp);
211 			}
212 		}
213 
214 		if ((kind & CTLTYPE) == CTLTYPE_INT ||
215 		    (kind & CTLTYPE) == CTLTYPE_UINT ||
216 		    (kind & CTLTYPE) == CTLTYPE_LONG ||
217 		    (kind & CTLTYPE) == CTLTYPE_ULONG ||
218 		    (kind & CTLTYPE) == CTLTYPE_QUAD) {
219 			if (strlen(newval) == 0)
220 				errx(1, "empty numeric value");
221 		}
222 
223 		switch (kind & CTLTYPE) {
224 			case CTLTYPE_INT:
225 				intval = (int)strtol(newval, &endptr, 0);
226 				if (endptr == newval || *endptr != '\0')
227 					errx(1, "invalid integer '%s'",
228 					    newval);
229 				newval = &intval;
230 				newsize = sizeof(intval);
231 				break;
232 			case CTLTYPE_UINT:
233 				uintval = (int) strtoul(newval, &endptr, 0);
234 				if (endptr == newval || *endptr != '\0')
235 					errx(1, "invalid unsigned integer '%s'",
236 					    newval);
237 				newval = &uintval;
238 				newsize = sizeof uintval;
239 				break;
240 			case CTLTYPE_LONG:
241 				longval = strtol(newval, &endptr, 0);
242 				if (endptr == newval || *endptr != '\0')
243 					errx(1, "invalid long integer '%s'",
244 					    newval);
245 				newval = &longval;
246 				newsize = sizeof longval;
247 				break;
248 			case CTLTYPE_ULONG:
249 				ulongval = strtoul(newval, &endptr, 0);
250 				if (endptr == newval || *endptr != '\0')
251 					errx(1, "invalid unsigned long integer"
252 					    " '%s'", newval);
253 				newval = &ulongval;
254 				newsize = sizeof ulongval;
255 				break;
256 			case CTLTYPE_STRING:
257 				break;
258 			case CTLTYPE_QUAD:
259 				sscanf(newval, "%qd", &quadval);
260 				newval = &quadval;
261 				newsize = sizeof(quadval);
262 				break;
263 			case CTLTYPE_OPAQUE:
264 				if (strcmp(fmt, "T,dev_t") == 0) {
265 					set_T_dev_t ((char*)newval, &newval, &newsize);
266 					break;
267 				}
268 				/* FALLTHROUGH */
269 			default:
270 				errx(1, "oid '%s' is type %d,"
271 					" cannot set that", bufp,
272 					kind & CTLTYPE);
273 		}
274 
275 		i = show_var(mib, len);
276 		if (sysctl(mib, len, 0, 0, newval, newsize) == -1) {
277 			if (!i && !bflag)
278 				putchar('\n');
279 			switch (errno) {
280 			case EOPNOTSUPP:
281 				errx(1, "%s: value is not available",
282 					string);
283 			case ENOTDIR:
284 				errx(1, "%s: specification is incomplete",
285 					string);
286 			case ENOMEM:
287 				errx(1, "%s: type is unknown to this program",
288 					string);
289 			default:
290 				warn("%s", string);
291 				return;
292 			}
293 		}
294 		if (!bflag)
295 			printf(" -> ");
296 		i = nflag;
297 		nflag = 1;
298 		j = show_var(mib, len);
299 		if (!j && !bflag)
300 			putchar('\n');
301 		nflag = i;
302 	}
303 }
304 
305 /* These functions will dump out various interesting structures. */
306 
307 static int
308 S_clockinfo(int l2, void *p)
309 {
310 	struct clockinfo *ci = (struct clockinfo*)p;
311 	if (l2 != sizeof(*ci)) {
312 		warnx("S_clockinfo %d != %d", l2, sizeof(*ci));
313 		return (0);
314 	}
315 	printf(hflag ? "{ hz = %'d, tick = %'d, profhz = %'d, stathz = %'d }" :
316 		"{ hz = %d, tick = %d, profhz = %d, stathz = %d }",
317 		ci->hz, ci->tick, ci->profhz, ci->stathz);
318 	return (0);
319 }
320 
321 static int
322 S_loadavg(int l2, void *p)
323 {
324 	struct loadavg *tv = (struct loadavg*)p;
325 
326 	if (l2 != sizeof(*tv)) {
327 		warnx("S_loadavg %d != %d", l2, sizeof(*tv));
328 		return (0);
329 	}
330 	printf(hflag ? "{ %'.2f %'.2f %'.2f }" : "{ %.2f %.2f %.2f }",
331 		(double)tv->ldavg[0]/(double)tv->fscale,
332 		(double)tv->ldavg[1]/(double)tv->fscale,
333 		(double)tv->ldavg[2]/(double)tv->fscale);
334 	return (0);
335 }
336 
337 static int
338 S_timeval(int l2, void *p)
339 {
340 	struct timeval *tv = (struct timeval*)p;
341 	time_t tv_sec;
342 	char *p1, *p2;
343 
344 	if (l2 != sizeof(*tv)) {
345 		warnx("S_timeval %d != %d", l2, sizeof(*tv));
346 		return (0);
347 	}
348 	printf(hflag ? "{ sec = %'ld, usec = %'ld } " :
349 		"{ sec = %ld, usec = %ld } ",
350 		tv->tv_sec, tv->tv_usec);
351 	tv_sec = tv->tv_sec;
352 	p1 = strdup(ctime(&tv_sec));
353 	for (p2=p1; *p2 ; p2++)
354 		if (*p2 == '\n')
355 			*p2 = '\0';
356 	fputs(p1, stdout);
357 	return (0);
358 }
359 
360 static int
361 S_vmtotal(int l2, void *p)
362 {
363 	struct vmtotal *v = (struct vmtotal *)p;
364 	int pageKilo = getpagesize() / 1024;
365 
366 	if (l2 != sizeof(*v)) {
367 		warnx("S_vmtotal %d != %d", l2, sizeof(*v));
368 		return (0);
369 	}
370 
371 	printf(
372 	    "\nSystem wide totals computed every five seconds:"
373 	    " (values in kilobytes)\n");
374 	printf("===============================================\n");
375 	printf(
376 	    "Processes:\t\t(RUNQ: %hu Disk Wait: %hu Page Wait: "
377 	    "%hu Sleep: %hu)\n",
378 	    v->t_rq, v->t_dw, v->t_pw, v->t_sl);
379 	printf(
380 	    "Virtual Memory:\t\t(Total: %luK, Active %lldK)\n",
381 	    (unsigned long)v->t_vm / 1024,
382 	    (long long)v->t_avm * pageKilo);
383 	printf("Real Memory:\t\t(Total: %lldK Active %lldK)\n",
384 	    (long long)v->t_rm * pageKilo, (long long)v->t_arm * pageKilo);
385 	printf("Shared Virtual Memory:\t(Total: %lldK Active: %lldK)\n",
386 	    (long long)v->t_vmshr * pageKilo,
387 	    (long long)v->t_avmshr * pageKilo);
388 	printf("Shared Real Memory:\t(Total: %lldK Active: %lldK)\n",
389 	    (long long)v->t_rmshr * pageKilo,
390 	    (long long)v->t_armshr * pageKilo);
391 	printf("Free Memory Pages:\t%ldK\n", (long long)v->t_free * pageKilo);
392 
393 	return (0);
394 }
395 
396 static int
397 T_dev_t(int l2, void *p)
398 {
399 	dev_t *d = (dev_t *)p;
400 	if (l2 != sizeof(*d)) {
401 		warnx("T_dev_T %d != %d", l2, sizeof(*d));
402 		return (0);
403 	}
404 	if ((int)(*d) != -1) {
405 		if (minor(*d) > 255 || minor(*d) < 0)
406 			printf("{ major = %d, minor = 0x%x }",
407 				major(*d), minor(*d));
408 		else
409 			printf("{ major = %d, minor = %d }",
410 				major(*d), minor(*d));
411 	}
412 	return (0);
413 }
414 
415 static void
416 set_T_dev_t (char *path, void **val, size_t *size)
417 {
418 	static struct stat statb;
419 
420 	if (strcmp(path, "none") && strcmp(path, "off")) {
421 		int rc = stat (path, &statb);
422 		if (rc) {
423 			err(1, "cannot stat %s", path);
424 		}
425 
426 		if (!S_ISCHR(statb.st_mode)) {
427 			errx(1, "must specify a device special file.");
428 		}
429 	} else {
430 		statb.st_rdev = NODEV;
431 	}
432 	*val = (char*) &statb.st_rdev;
433 	*size = sizeof statb.st_rdev;
434 }
435 
436 /*
437  * These functions uses a presently undocumented interface to the kernel
438  * to walk the tree and get the type so it can print the value.
439  * This interface is under work and consideration, and should probably
440  * be killed with a big axe by the first person who can find the time.
441  * (be aware though, that the proper interface isn't as obvious as it
442  * may seem, there are various conflicting requirements.
443  */
444 
445 static int
446 name2oid(char *name, int *oidp)
447 {
448 	int oid[2];
449 	int i;
450 	size_t j;
451 
452 	oid[0] = 0;
453 	oid[1] = 3;
454 
455 	j = CTL_MAXNAME * sizeof(int);
456 	i = sysctl(oid, 2, oidp, &j, name, strlen(name));
457 	if (i < 0)
458 		return i;
459 	j /= sizeof(int);
460 	return (j);
461 }
462 
463 static int
464 oidfmt(int *oid, int len, char *fmt, u_int *kind)
465 {
466 	int qoid[CTL_MAXNAME+2];
467 	u_char buf[BUFSIZ];
468 	int i;
469 	size_t j;
470 
471 	qoid[0] = 0;
472 	qoid[1] = 4;
473 	memcpy(qoid + 2, oid, len * sizeof(int));
474 
475 	j = sizeof(buf);
476 	i = sysctl(qoid, len + 2, buf, &j, 0, 0);
477 	if (i)
478 		err(1, "sysctl fmt %d %d %d", i, j, errno);
479 
480 	if (kind)
481 		*kind = *(u_int *)buf;
482 
483 	if (fmt)
484 		strcpy(fmt, (char *)(buf + sizeof(u_int)));
485 	return 0;
486 }
487 
488 /*
489  * This formats and outputs the value of one variable
490  *
491  * Returns zero if anything was actually output.
492  * Returns one if didn't know what to do with this.
493  * Return minus one if we had errors.
494  */
495 
496 static int
497 show_var(int *oid, int nlen)
498 {
499 	u_char buf[BUFSIZ], *val, *p;
500 	char name[BUFSIZ], *fmt, *sep;
501 	int qoid[CTL_MAXNAME+2];
502 	int i;
503 	size_t j, len;
504 	u_int kind;
505 	int (*func)(int, void *);
506 
507 	qoid[0] = 0;
508 	memcpy(qoid + 2, oid, nlen * sizeof(int));
509 
510 	qoid[1] = 1;
511 	j = sizeof(name);
512 	i = sysctl(qoid, nlen + 2, name, &j, 0, 0);
513 	if (i || !j)
514 		err(1, "sysctl name %d %d %d", i, j, errno);
515 
516 	if (Nflag) {
517 		printf("%s", name);
518 		return (0);
519 	}
520 
521 	if (eflag)
522 		sep = "=";
523 	else
524 		sep = ": ";
525 
526 	if (dflag) {	/* just print description */
527 		qoid[1] = 5;
528 		j = sizeof(buf);
529 		i = sysctl(qoid, nlen + 2, buf, &j, 0, 0);
530 		if (!nflag)
531 			printf("%s%s", name, sep);
532 		printf("%s", buf);
533 		return (0);
534 	}
535 	/* find an estimate of how much we need for this var */
536 	j = 0;
537 	i = sysctl(oid, nlen, 0, &j, 0, 0);
538 	j += j; /* we want to be sure :-) */
539 
540 	val = alloca(j + 1);
541 	len = j;
542 	i = sysctl(oid, nlen, val, &len, 0, 0);
543 	if (i || !len)
544 		return (1);
545 
546 	if (bflag) {
547 		fwrite(val, 1, len, stdout);
548 		return (0);
549 	}
550 	val[len] = '\0';
551 	fmt = buf;
552 	oidfmt(oid, nlen, fmt, &kind);
553 	p = val;
554 	switch (*fmt) {
555 	case 'A':
556 		if (!nflag)
557 			printf("%s%s", name, sep);
558 		printf("%.*s", len, p);
559 		return (0);
560 
561 	case 'I':
562 		if (!nflag)
563 			printf("%s%s", name, sep);
564 		fmt++;
565 		val = "";
566 		while (len >= sizeof(int)) {
567 			fputs(val, stdout);
568 			if(*fmt == 'U')
569 				printf(hflag ? "%'u" : "%u", *(unsigned int *)p);
570 			else
571 				printf(hflag ? "%'d" : "%d", *(int *)p);
572 			val = " ";
573 			len -= sizeof(int);
574 			p += sizeof(int);
575 		}
576 		return (0);
577 
578 	case 'L':
579 		if (!nflag)
580 			printf("%s%s", name, sep);
581 		fmt++;
582 		val = "";
583 		while (len >= sizeof(long)) {
584 			fputs(val, stdout);
585 			if(*fmt == 'U')
586 				printf(hflag ? "%'lu" : "%lu", *(unsigned long *)p);
587 			else
588 				printf(hflag ? "%'ld" : "%ld", *(long *)p);
589 			val = " ";
590 			len -= sizeof(long);
591 			p += sizeof(long);
592 		}
593 		return (0);
594 
595 	case 'P':
596 		if (!nflag)
597 			printf("%s%s", name, sep);
598 		printf("%p", *(void **)p);
599 		return (0);
600 
601 	case 'T':
602 	case 'S':
603 		i = 0;
604 		if (strcmp(fmt, "S,clockinfo") == 0)
605 			func = S_clockinfo;
606 		else if (strcmp(fmt, "S,timeval") == 0)
607 			func = S_timeval;
608 		else if (strcmp(fmt, "S,loadavg") == 0)
609 			func = S_loadavg;
610 		else if (strcmp(fmt, "S,vmtotal") == 0)
611 			func = S_vmtotal;
612 		else if (strcmp(fmt, "T,dev_t") == 0)
613 			func = T_dev_t;
614 		else
615 			func = NULL;
616 		if (func) {
617 			if (!nflag)
618 				printf("%s%s", name, sep);
619 			return ((*func)(len, p));
620 		}
621 		/* FALLTHROUGH */
622 	default:
623 		if (!oflag && !xflag)
624 			return (1);
625 		if (!nflag)
626 			printf("%s%s", name, sep);
627 		printf("Format:%s Length:%d Dump:0x", fmt, len);
628 		while (len-- && (xflag || p < val + 16))
629 			printf("%02x", *p++);
630 		if (!xflag && len > 16)
631 			printf("...");
632 		return (0);
633 	}
634 	return (1);
635 }
636 
637 static int
638 sysctl_all (int *oid, int len)
639 {
640 	int name1[22], name2[22];
641 	int i, j;
642 	size_t l1, l2;
643 
644 	name1[0] = 0;
645 	name1[1] = 2;
646 	l1 = 2;
647 	if (len) {
648 		memcpy(name1+2, oid, len * sizeof(int));
649 		l1 += len;
650 	} else {
651 		name1[2] = 1;
652 		l1++;
653 	}
654 	for (;;) {
655 		l2 = sizeof(name2);
656 		j = sysctl(name1, l1, name2, &l2, 0, 0);
657 		if (j < 0) {
658 			if (errno == ENOENT)
659 				return 0;
660 			else
661 				err(1, "sysctl(getnext) %d %d", j, l2);
662 		}
663 
664 		l2 /= sizeof(int);
665 
666 		if (l2 < len)
667 			return 0;
668 
669 		for (i = 0; i < len; i++)
670 			if (name2[i] != oid[i])
671 				return 0;
672 
673 		i = show_var(name2, l2);
674 		if (!i && !bflag)
675 			putchar('\n');
676 
677 		memcpy(name1+2, name2, l2 * sizeof(int));
678 		l1 = 2 + l2;
679 	}
680 }
681