xref: /freebsd/sbin/sysctl/sysctl.c (revision 7773002178c8dbc52b44e4d705f07706409af8e4)
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 <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64 #include <unistd.h>
65 
66 static int	aflag, bflag, dflag, eflag, Nflag, nflag, oflag, xflag;
67 
68 static int	oidfmt(int *, int, char *, u_int *);
69 static void	parse(char *);
70 static int	show_var(int *, int);
71 static int	sysctl_all (int *oid, int len);
72 static int	name2oid(char *, int *);
73 
74 static void	set_T_dev_t (char *, void **, size_t *);
75 
76 static void
77 usage(void)
78 {
79 
80 	(void)fprintf(stderr, "%s\n%s\n",
81 	    "usage: sysctl [-bdeNnox] variable[=value] ...",
82 	    "       sysctl [-bdeNnox] -a");
83 	exit(1);
84 }
85 
86 int
87 main(int argc, char **argv)
88 {
89 	int ch;
90 	setbuf(stdout,0);
91 	setbuf(stderr,0);
92 
93 	while ((ch = getopt(argc, argv, "AabdeNnowxX")) != -1) {
94 		switch (ch) {
95 		case 'A':
96 			/* compatibility */
97 			aflag = oflag = 1;
98 			break;
99 		case 'a':
100 			aflag = 1;
101 			break;
102 		case 'b':
103 			bflag = 1;
104 			break;
105 		case 'd':
106 			dflag = 1;
107 			break;
108 		case 'e':
109 			eflag = 1;
110 			break;
111 		case 'N':
112 			Nflag = 1;
113 			break;
114 		case 'n':
115 			nflag = 1;
116 			break;
117 		case 'o':
118 			oflag = 1;
119 			break;
120 		case 'w':
121 			/* compatibility */
122 			/* ignored */
123 			break;
124 		case 'X':
125 			/* compatibility */
126 			aflag = xflag = 1;
127 			break;
128 		case 'x':
129 			xflag = 1;
130 			break;
131 		default:
132 			usage();
133 		}
134 	}
135 	argc -= optind;
136 	argv += optind;
137 
138 	if (Nflag && nflag)
139 		usage();
140 	if (aflag && argc == 0)
141 		exit(sysctl_all(0, 0));
142 	if (argc == 0)
143 		usage();
144 	while (argc-- > 0)
145 		parse(*argv++);
146 	exit(0);
147 }
148 
149 /*
150  * Parse a name into a MIB entry.
151  * Lookup and print out the MIB entry if it exists.
152  * Set a new value if requested.
153  */
154 static void
155 parse(char *string)
156 {
157 	int len, i, j;
158 	void *newval = 0;
159 	int intval;
160 	unsigned int uintval;
161 	long longval;
162 	unsigned long ulongval;
163 	size_t newsize = 0;
164 	quad_t quadval;
165 	int mib[CTL_MAXNAME];
166 	char *cp, *bufp, buf[BUFSIZ], *endptr, fmt[BUFSIZ];
167 	u_int kind;
168 
169 	bufp = buf;
170 	snprintf(buf, BUFSIZ, "%s", string);
171 	if ((cp = strchr(string, '=')) != NULL) {
172 		*strchr(buf, '=') = '\0';
173 		*cp++ = '\0';
174 		while (isspace(*cp))
175 			cp++;
176 		newval = cp;
177 		newsize = strlen(cp);
178 	}
179 	len = name2oid(bufp, mib);
180 
181 	if (len < 0)
182 		errx(1, "unknown oid '%s'", bufp);
183 
184 	if (oidfmt(mib, len, fmt, &kind))
185 		err(1, "couldn't find format of oid '%s'", bufp);
186 
187 	if (newval == NULL) {
188 		if ((kind & CTLTYPE) == CTLTYPE_NODE) {
189 			sysctl_all(mib, len);
190 		} else {
191 			i = show_var(mib, len);
192 			if (!i && !bflag)
193 				putchar('\n');
194 		}
195 	} else {
196 		if ((kind & CTLTYPE) == CTLTYPE_NODE)
197 			errx(1, "oid '%s' isn't a leaf node", bufp);
198 
199 		if (!(kind & CTLFLAG_WR)) {
200 			if (kind & CTLFLAG_TUN) {
201 				warnx("oid '%s' is a read only tunable", bufp);
202 				errx(1, "Tunable values are set in /boot/loader.conf");
203 			} else {
204 				errx(1, "oid '%s' is read only", bufp);
205 			}
206 		}
207 
208 		if ((kind & CTLTYPE) == CTLTYPE_INT ||
209 		    (kind & CTLTYPE) == CTLTYPE_UINT ||
210 		    (kind & CTLTYPE) == CTLTYPE_LONG ||
211 		    (kind & CTLTYPE) == CTLTYPE_ULONG) {
212 			if (strlen(newval) == 0)
213 				errx(1, "empty numeric value");
214 		}
215 
216 		switch (kind & CTLTYPE) {
217 			case CTLTYPE_INT:
218 				intval = (int)strtol(newval, &endptr, 0);
219 				if (endptr == newval || *endptr != '\0')
220 					errx(1, "invalid integer '%s'",
221 					    newval);
222 				newval = &intval;
223 				newsize = sizeof(intval);
224 				break;
225 			case CTLTYPE_UINT:
226 				uintval = (int) strtoul(newval, &endptr, 0);
227 				if (endptr == newval || *endptr != '\0')
228 					errx(1, "invalid unsigned integer '%s'",
229 					    newval);
230 				newval = &uintval;
231 				newsize = sizeof uintval;
232 				break;
233 			case CTLTYPE_LONG:
234 				longval = strtol(newval, &endptr, 0);
235 				if (endptr == newval || *endptr != '\0')
236 					errx(1, "invalid long integer '%s'",
237 					    newval);
238 				newval = &longval;
239 				newsize = sizeof longval;
240 				break;
241 			case CTLTYPE_ULONG:
242 				ulongval = strtoul(newval, &endptr, 0);
243 				if (endptr == newval || *endptr != '\0')
244 					errx(1, "invalid unsigned long integer"
245 					    " '%s'", newval);
246 				newval = &ulongval;
247 				newsize = sizeof ulongval;
248 				break;
249 			case CTLTYPE_STRING:
250 				break;
251 			case CTLTYPE_QUAD:
252 				sscanf(newval, "%qd", &quadval);
253 				newval = &quadval;
254 				newsize = sizeof(quadval);
255 				break;
256 			case CTLTYPE_OPAQUE:
257 				if (strcmp(fmt, "T,dev_t") == 0) {
258 					set_T_dev_t ((char*)newval, &newval, &newsize);
259 					break;
260 				}
261 				/* FALLTHROUGH */
262 			default:
263 				errx(1, "oid '%s' is type %d,"
264 					" cannot set that", bufp,
265 					kind & CTLTYPE);
266 		}
267 
268 		i = show_var(mib, len);
269 		if (sysctl(mib, len, 0, 0, newval, newsize) == -1) {
270 			if (!i && !bflag)
271 				putchar('\n');
272 			switch (errno) {
273 			case EOPNOTSUPP:
274 				errx(1, "%s: value is not available",
275 					string);
276 			case ENOTDIR:
277 				errx(1, "%s: specification is incomplete",
278 					string);
279 			case ENOMEM:
280 				errx(1, "%s: type is unknown to this program",
281 					string);
282 			default:
283 				warn("%s", string);
284 				return;
285 			}
286 		}
287 		if (!bflag)
288 			printf(" -> ");
289 		i = nflag;
290 		nflag = 1;
291 		j = show_var(mib, len);
292 		if (!j && !bflag)
293 			putchar('\n');
294 		nflag = i;
295 	}
296 }
297 
298 /* These functions will dump out various interesting structures. */
299 
300 static int
301 S_clockinfo(int l2, void *p)
302 {
303 	struct clockinfo *ci = (struct clockinfo*)p;
304 	if (l2 != sizeof(*ci)) {
305 		warnx("S_clockinfo %d != %d", l2, sizeof(*ci));
306 		return (0);
307 	}
308 	printf("{ hz = %d, tick = %d, profhz = %d, stathz = %d }",
309 		ci->hz, ci->tick, ci->profhz, ci->stathz);
310 	return (0);
311 }
312 
313 static int
314 S_loadavg(int l2, void *p)
315 {
316 	struct loadavg *tv = (struct loadavg*)p;
317 
318 	if (l2 != sizeof(*tv)) {
319 		warnx("S_loadavg %d != %d", l2, sizeof(*tv));
320 		return (0);
321 	}
322 	printf("{ %.2f %.2f %.2f }",
323 		(double)tv->ldavg[0]/(double)tv->fscale,
324 		(double)tv->ldavg[1]/(double)tv->fscale,
325 		(double)tv->ldavg[2]/(double)tv->fscale);
326 	return (0);
327 }
328 
329 static int
330 S_timeval(int l2, void *p)
331 {
332 	struct timeval *tv = (struct timeval*)p;
333 	time_t tv_sec;
334 	char *p1, *p2;
335 
336 	if (l2 != sizeof(*tv)) {
337 		warnx("S_timeval %d != %d", l2, sizeof(*tv));
338 		return (0);
339 	}
340 	printf("{ sec = %ld, usec = %ld } ",
341 		tv->tv_sec, tv->tv_usec);
342 	tv_sec = tv->tv_sec;
343 	p1 = strdup(ctime(&tv_sec));
344 	for (p2=p1; *p2 ; p2++)
345 		if (*p2 == '\n')
346 			*p2 = '\0';
347 	fputs(p1, stdout);
348 	return (0);
349 }
350 
351 static int
352 S_vmtotal(int l2, void *p)
353 {
354 	struct vmtotal *v = (struct vmtotal *)p;
355 	int pageKilo = getpagesize() / 1024;
356 
357 	if (l2 != sizeof(*v)) {
358 		warnx("S_vmtotal %d != %d", l2, sizeof(*v));
359 		return (0);
360 	}
361 
362 	printf(
363 	    "\nSystem wide totals computed every five seconds:"
364 	    " (values in kilobytes)\n");
365 	printf("===============================================\n");
366 	printf(
367 	    "Processes:\t\t(RUNQ: %hu Disk Wait: %hu Page Wait: "
368 	    "%hu Sleep: %hu)\n",
369 	    v->t_rq, v->t_dw, v->t_pw, v->t_sl);
370 	printf(
371 	    "Virtual Memory:\t\t(Total: %luK, Active %lldK)\n",
372 	    (unsigned long)v->t_vm / 1024,
373 	    (long long)v->t_avm * pageKilo);
374 	printf("Real Memory:\t\t(Total: %lldK Active %lldK)\n",
375 	    (long long)v->t_rm * pageKilo, (long long)v->t_arm * pageKilo);
376 	printf("Shared Virtual Memory:\t(Total: %lldK Active: %lldK)\n",
377 	    (long long)v->t_vmshr * pageKilo,
378 	    (long long)v->t_avmshr * pageKilo);
379 	printf("Shared Real Memory:\t(Total: %lldK Active: %lldK)\n",
380 	    (long long)v->t_rmshr * pageKilo,
381 	    (long long)v->t_armshr * pageKilo);
382 	printf("Free Memory Pages:\t%ldK\n", (long long)v->t_free * pageKilo);
383 
384 	return (0);
385 }
386 
387 static int
388 T_dev_t(int l2, void *p)
389 {
390 	dev_t *d = (dev_t *)p;
391 	if (l2 != sizeof(*d)) {
392 		warnx("T_dev_T %d != %d", l2, sizeof(*d));
393 		return (0);
394 	}
395 	if ((int)(*d) != -1) {
396 		if (minor(*d) > 255 || minor(*d) < 0)
397 			printf("{ major = %d, minor = 0x%x }",
398 				major(*d), minor(*d));
399 		else
400 			printf("{ major = %d, minor = %d }",
401 				major(*d), minor(*d));
402 	}
403 	return (0);
404 }
405 
406 static void
407 set_T_dev_t (char *path, void **val, size_t *size)
408 {
409 	static struct stat statb;
410 
411 	if (strcmp(path, "none") && strcmp(path, "off")) {
412 		int rc = stat (path, &statb);
413 		if (rc) {
414 			err(1, "cannot stat %s", path);
415 		}
416 
417 		if (!S_ISCHR(statb.st_mode)) {
418 			errx(1, "must specify a device special file.");
419 		}
420 	} else {
421 		statb.st_rdev = NODEV;
422 	}
423 	*val = (char*) &statb.st_rdev;
424 	*size = sizeof statb.st_rdev;
425 }
426 
427 /*
428  * These functions uses a presently undocumented interface to the kernel
429  * to walk the tree and get the type so it can print the value.
430  * This interface is under work and consideration, and should probably
431  * be killed with a big axe by the first person who can find the time.
432  * (be aware though, that the proper interface isn't as obvious as it
433  * may seem, there are various conflicting requirements.
434  */
435 
436 static int
437 name2oid(char *name, int *oidp)
438 {
439 	int oid[2];
440 	int i;
441 	size_t j;
442 
443 	oid[0] = 0;
444 	oid[1] = 3;
445 
446 	j = CTL_MAXNAME * sizeof(int);
447 	i = sysctl(oid, 2, oidp, &j, name, strlen(name));
448 	if (i < 0)
449 		return i;
450 	j /= sizeof(int);
451 	return (j);
452 }
453 
454 static int
455 oidfmt(int *oid, int len, char *fmt, u_int *kind)
456 {
457 	int qoid[CTL_MAXNAME+2];
458 	u_char buf[BUFSIZ];
459 	int i;
460 	size_t j;
461 
462 	qoid[0] = 0;
463 	qoid[1] = 4;
464 	memcpy(qoid + 2, oid, len * sizeof(int));
465 
466 	j = sizeof(buf);
467 	i = sysctl(qoid, len + 2, buf, &j, 0, 0);
468 	if (i)
469 		err(1, "sysctl fmt %d %d %d", i, j, errno);
470 
471 	if (kind)
472 		*kind = *(u_int *)buf;
473 
474 	if (fmt)
475 		strcpy(fmt, (char *)(buf + sizeof(u_int)));
476 	return 0;
477 }
478 
479 /*
480  * This formats and outputs the value of one variable
481  *
482  * Returns zero if anything was actually output.
483  * Returns one if didn't know what to do with this.
484  * Return minus one if we had errors.
485  */
486 
487 static int
488 show_var(int *oid, int nlen)
489 {
490 	u_char buf[BUFSIZ], *val, *p;
491 	char name[BUFSIZ], *fmt, *sep;
492 	int qoid[CTL_MAXNAME+2];
493 	int i;
494 	size_t j, len;
495 	u_int kind;
496 	int (*func)(int, void *);
497 
498 	qoid[0] = 0;
499 	memcpy(qoid + 2, oid, nlen * sizeof(int));
500 
501 	qoid[1] = 1;
502 	j = sizeof(name);
503 	i = sysctl(qoid, nlen + 2, name, &j, 0, 0);
504 	if (i || !j)
505 		err(1, "sysctl name %d %d %d", i, j, errno);
506 
507 	if (Nflag) {
508 		printf("%s", name);
509 		return (0);
510 	}
511 
512 	if (eflag)
513 		sep = "=";
514 	else
515 		sep = ": ";
516 
517 	if (dflag) {	/* just print description */
518 		qoid[1] = 5;
519 		j = sizeof(buf);
520 		i = sysctl(qoid, nlen + 2, buf, &j, 0, 0);
521 		if (!nflag)
522 			printf("%s%s", name, sep);
523 		printf("%s", buf);
524 		return (0);
525 	}
526 	/* find an estimate of how much we need for this var */
527 	j = 0;
528 	i = sysctl(oid, nlen, 0, &j, 0, 0);
529 	j += j; /* we want to be sure :-) */
530 
531 	val = alloca(j + 1);
532 	len = j;
533 	i = sysctl(oid, nlen, val, &len, 0, 0);
534 	if (i || !len)
535 		return (1);
536 
537 	if (bflag) {
538 		fwrite(val, 1, len, stdout);
539 		return (0);
540 	}
541 	val[len] = '\0';
542 	fmt = buf;
543 	oidfmt(oid, nlen, fmt, &kind);
544 	p = val;
545 	switch (*fmt) {
546 	case 'A':
547 		if (!nflag)
548 			printf("%s%s", name, sep);
549 		printf("%.*s", len, p);
550 		return (0);
551 
552 	case 'I':
553 		if (!nflag)
554 			printf("%s%s", name, sep);
555 		fmt++;
556 		val = "";
557 		while (len >= sizeof(int)) {
558 			if(*fmt == 'U')
559 				printf("%s%u", val, *(unsigned int *)p);
560 			else
561 				printf("%s%d", val, *(int *)p);
562 			val = " ";
563 			len -= sizeof(int);
564 			p += sizeof(int);
565 		}
566 		return (0);
567 
568 	case 'L':
569 		if (!nflag)
570 			printf("%s%s", name, sep);
571 		fmt++;
572 		val = "";
573 		while (len >= sizeof(long)) {
574 			if(*fmt == 'U')
575 				printf("%s%lu", val, *(unsigned long *)p);
576 			else
577 				printf("%s%ld", val, *(long *)p);
578 			val = " ";
579 			len -= sizeof(long);
580 			p += sizeof(long);
581 		}
582 		return (0);
583 
584 	case 'P':
585 		if (!nflag)
586 			printf("%s%s", name, sep);
587 		printf("%p", *(void **)p);
588 		return (0);
589 
590 	case 'T':
591 	case 'S':
592 		i = 0;
593 		if (strcmp(fmt, "S,clockinfo") == 0)
594 			func = S_clockinfo;
595 		else if (strcmp(fmt, "S,timeval") == 0)
596 			func = S_timeval;
597 		else if (strcmp(fmt, "S,loadavg") == 0)
598 			func = S_loadavg;
599 		else if (strcmp(fmt, "S,vmtotal") == 0)
600 			func = S_vmtotal;
601 		else if (strcmp(fmt, "T,dev_t") == 0)
602 			func = T_dev_t;
603 		else
604 			func = NULL;
605 		if (func) {
606 			if (!nflag)
607 				printf("%s%s", name, sep);
608 			return ((*func)(len, p));
609 		}
610 		/* FALLTHROUGH */
611 	default:
612 		if (!oflag && !xflag)
613 			return (1);
614 		if (!nflag)
615 			printf("%s%s", name, sep);
616 		printf("Format:%s Length:%d Dump:0x", fmt, len);
617 		while (len-- && (xflag || p < val + 16))
618 			printf("%02x", *p++);
619 		if (!xflag && len > 16)
620 			printf("...");
621 		return (0);
622 	}
623 	return (1);
624 }
625 
626 static int
627 sysctl_all (int *oid, int len)
628 {
629 	int name1[22], name2[22];
630 	int i, j;
631 	size_t l1, l2;
632 
633 	name1[0] = 0;
634 	name1[1] = 2;
635 	l1 = 2;
636 	if (len) {
637 		memcpy(name1+2, oid, len * sizeof(int));
638 		l1 += len;
639 	} else {
640 		name1[2] = 1;
641 		l1++;
642 	}
643 	for (;;) {
644 		l2 = sizeof(name2);
645 		j = sysctl(name1, l1, name2, &l2, 0, 0);
646 		if (j < 0) {
647 			if (errno == ENOENT)
648 				return 0;
649 			else
650 				err(1, "sysctl(getnext) %d %d", j, l2);
651 		}
652 
653 		l2 /= sizeof(int);
654 
655 		if (l2 < len)
656 			return 0;
657 
658 		for (i = 0; i < len; i++)
659 			if (name2[i] != oid[i])
660 				return 0;
661 
662 		i = show_var(name2, l2);
663 		if (!i && !bflag)
664 			putchar('\n');
665 
666 		memcpy(name1+2, name2, l2 * sizeof(int));
667 		l1 = 2 + l2;
668 	}
669 }
670