xref: /netbsd-src/usr.bin/pkill/pkill.c (revision ba65fde2d7fefa7d39838fa5fa855e62bd606b5e)
1 /*	$NetBSD: pkill.c,v 1.29 2013/01/02 10:36:07 dsl Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __RCSID("$NetBSD: pkill.c,v 1.29 2013/01/02 10:36:07 dsl Exp $");
35 #endif /* !lint */
36 
37 #include <sys/types.h>
38 #include <sys/param.h>
39 #include <sys/sysctl.h>
40 #include <sys/proc.h>
41 #include <sys/queue.h>
42 #include <sys/resource.h>
43 #include <sys/stat.h>
44 
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <limits.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include <signal.h>
51 #include <regex.h>
52 #include <ctype.h>
53 #include <kvm.h>
54 #include <err.h>
55 #include <pwd.h>
56 #include <grp.h>
57 #include <errno.h>
58 #include <paths.h>
59 
60 #define	STATUS_MATCH	0
61 #define	STATUS_NOMATCH	1
62 #define	STATUS_BADUSAGE	2
63 #define	STATUS_ERROR	3
64 
65 enum listtype {
66 	LT_GENERIC,
67 	LT_USER,
68 	LT_GROUP,
69 	LT_TTY,
70 	LT_PGRP,
71 	LT_SID
72 };
73 
74 struct list {
75 	SLIST_ENTRY(list) li_chain;
76 	long	li_number;
77 };
78 
79 SLIST_HEAD(listhead, list);
80 
81 static struct kinfo_proc2	*plist;
82 static char	*selected;
83 static const char *delim = "\n";
84 static int	nproc;
85 static int	pgrep;
86 static int	prenice;
87 static int	signum = SIGTERM;
88 static int	nicenum;
89 static int	newest;
90 static int	inverse;
91 static int	longfmt;
92 static int	matchargs;
93 static int	fullmatch;
94 static int	cflags = REG_EXTENDED;
95 static kvm_t	*kd;
96 static pid_t	mypid;
97 
98 static struct listhead euidlist = SLIST_HEAD_INITIALIZER(list);
99 static struct listhead ruidlist = SLIST_HEAD_INITIALIZER(list);
100 static struct listhead rgidlist = SLIST_HEAD_INITIALIZER(list);
101 static struct listhead pgrplist = SLIST_HEAD_INITIALIZER(list);
102 static struct listhead ppidlist = SLIST_HEAD_INITIALIZER(list);
103 static struct listhead tdevlist = SLIST_HEAD_INITIALIZER(list);
104 static struct listhead sidlist = SLIST_HEAD_INITIALIZER(list);
105 
106 static void	usage(void) __dead;
107 static int	killact(const struct kinfo_proc2 *);
108 static int	reniceact(const struct kinfo_proc2 *);
109 static int	grepact(const struct kinfo_proc2 *);
110 static void	makelist(struct listhead *, enum listtype, char *);
111 
112 int
113 main(int argc, char **argv)
114 {
115 	char buf[_POSIX2_LINE_MAX], **pargv, *q;
116 	int i, j, ch, bestidx, rv, criteria;
117 	int (*action)(const struct kinfo_proc2 *);
118 	const struct kinfo_proc2 *kp;
119 	struct list *li;
120 	const char *p;
121 	u_int32_t bestsec, bestusec;
122 	regex_t reg;
123 	regmatch_t regmatch;
124 
125 	setprogname(argv[0]);
126 
127 	if (strcmp(getprogname(), "pgrep") == 0) {
128 		action = grepact;
129 		pgrep = 1;
130 	} else if (strcmp(getprogname(), "prenice") == 0) {
131 		prenice = 1;
132 
133 	} else {
134 		action = killact;
135 		p = argv[1];
136 
137 		if (argc > 1 && p[0] == '-') {
138 			p++;
139 			i = (int)strtol(p, &q, 10);
140 			if (*q == '\0') {
141 				signum = i;
142 				argv++;
143 				argc--;
144 			} else {
145 				if (strncasecmp(p, "sig", 3) == 0)
146 					p += 3;
147 				for (i = 1; i < NSIG; i++)
148 					if (strcasecmp(sys_signame[i], p) == 0)
149 						break;
150 				if (i != NSIG) {
151 					signum = i;
152 					argv++;
153 					argc--;
154 				}
155 			}
156 		}
157 	}
158 
159 	criteria = 0;
160 
161 	if (prenice) {
162 		if (argc < 2)
163 			usage();
164 
165 		if (strcmp(argv[1], "-l") == 0) {
166 			longfmt = 1;
167 			argv++;
168 			argc--;
169 		}
170 
171 		if (argc < 2)
172 			usage();
173 
174 		action = reniceact;
175 		p = argv[1];
176 
177 		i = (int)strtol(p, &q, 10);
178 		if (*q == '\0') {
179 			nicenum = i;
180 			argv++;
181 			argc--;
182 		} else
183 			usage();
184 	} else {
185 		while ((ch = getopt(argc, argv, "G:P:U:d:fg:ilns:t:u:vx")) != -1)
186 			switch (ch) {
187 			case 'G':
188 				makelist(&rgidlist, LT_GROUP, optarg);
189 				criteria = 1;
190 				break;
191 			case 'P':
192 				makelist(&ppidlist, LT_GENERIC, optarg);
193 				criteria = 1;
194 				break;
195 			case 'U':
196 				makelist(&ruidlist, LT_USER, optarg);
197 				criteria = 1;
198 				break;
199 			case 'd':
200 				if (!pgrep)
201 					usage();
202 				delim = optarg;
203 				break;
204 			case 'f':
205 				matchargs = 1;
206 				break;
207 			case 'g':
208 				makelist(&pgrplist, LT_PGRP, optarg);
209 				criteria = 1;
210 				break;
211 			case 'i':
212 				cflags |= REG_ICASE;
213 				break;
214 			case 'l':
215 				longfmt = 1;
216 				break;
217 			case 'n':
218 				newest = 1;
219 				criteria = 1;
220 				break;
221 			case 's':
222 				makelist(&sidlist, LT_SID, optarg);
223 				criteria = 1;
224 				break;
225 			case 't':
226 				makelist(&tdevlist, LT_TTY, optarg);
227 				criteria = 1;
228 				break;
229 			case 'u':
230 				makelist(&euidlist, LT_USER, optarg);
231 				criteria = 1;
232 				break;
233 			case 'v':
234 				inverse = 1;
235 				break;
236 			case 'x':
237 				fullmatch = 1;
238 				break;
239 			default:
240 				usage();
241 				/* NOTREACHED */
242 			}
243 		argc -= optind;
244 		argv += optind;
245 	}
246 
247 	if (argc != 0)
248 		criteria = 1;
249 	if (!criteria)
250 		usage();
251 
252 	mypid = getpid();
253 
254 	/*
255 	 * Retrieve the list of running processes from the kernel.
256 	 */
257 	kd = kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, buf);
258 	if (kd == NULL)
259 		errx(STATUS_ERROR, "Cannot open kernel files (%s)", buf);
260 
261 	plist = kvm_getproc2(kd, KERN_PROC_ALL, 0, sizeof(*plist), &nproc);
262 	if (plist == NULL)
263 		errx(STATUS_ERROR, "Cannot get process list (%s)",
264 		    kvm_geterr(kd));
265 
266 	/*
267 	 * Allocate memory which will be used to keep track of the
268 	 * selection.
269 	 */
270 	if ((selected = calloc((size_t)1, (size_t)nproc)) == NULL)
271 		err(STATUS_ERROR, "Cannot allocate memory for %d processes",
272 		    nproc);
273 
274 	/*
275 	 * Refine the selection.
276 	 */
277 	for (; *argv != NULL; argv++) {
278 		if ((rv = regcomp(&reg, *argv, cflags)) != 0) {
279 			(void)regerror(rv, &reg, buf, sizeof(buf));
280 			errx(STATUS_BADUSAGE,
281 			    "Cannot compile regular expression `%s' (%s)",
282 			    *argv, buf);
283 		}
284 
285 		for (i = 0, kp = plist; i < nproc; i++, kp++) {
286 			if ((kp->p_flag & P_SYSTEM) != 0 || kp->p_pid == mypid)
287 				continue;
288 
289 			if ((pargv = kvm_getargv2(kd, kp, 0)) == NULL)
290 				continue;
291 			if (matchargs) {
292 
293 				j = 0;
294 				while (j < (int)sizeof(buf) && *pargv != NULL) {
295 					j += snprintf(buf + j, sizeof(buf) - j,
296 					    pargv[1] != NULL ? "%s " : "%s",
297 					    pargv[0]);
298 					pargv++;
299 				}
300 			} else
301 				strlcpy(buf, pargv[0], sizeof(buf));
302 
303 			rv = regexec(&reg, buf, 1, &regmatch, 0);
304 			if (rv == 0) {
305 				if (fullmatch) {
306 					if (regmatch.rm_so == 0 &&
307 					    regmatch.rm_eo ==
308 					    (regoff_t)strlen(buf))
309 						selected[i] = 1;
310 				} else
311 					selected[i] = 1;
312 			} else if (rv != REG_NOMATCH) {
313 				(void)regerror(rv, &reg, buf, sizeof(buf));
314 				errx(STATUS_ERROR,
315 				    "Regular expression evaluation error (%s)",
316 				    buf);
317 			}
318 		}
319 
320 		regfree(&reg);
321 	}
322 
323 	for (i = 0, kp = plist; i < nproc; i++, kp++) {
324 		if ((kp->p_flag & P_SYSTEM) != 0)
325 			continue;
326 
327 		SLIST_FOREACH(li, &ruidlist, li_chain)
328 			if (kp->p_ruid == (uid_t)li->li_number)
329 				break;
330 		if (SLIST_FIRST(&ruidlist) != NULL && li == NULL) {
331 			selected[i] = 0;
332 			continue;
333 		}
334 
335 		SLIST_FOREACH(li, &rgidlist, li_chain)
336 			if (kp->p_rgid == (gid_t)li->li_number)
337 				break;
338 		if (SLIST_FIRST(&rgidlist) != NULL && li == NULL) {
339 			selected[i] = 0;
340 			continue;
341 		}
342 
343 		SLIST_FOREACH(li, &euidlist, li_chain)
344 			if (kp->p_uid == (uid_t)li->li_number)
345 				break;
346 		if (SLIST_FIRST(&euidlist) != NULL && li == NULL) {
347 			selected[i] = 0;
348 			continue;
349 		}
350 
351 		SLIST_FOREACH(li, &ppidlist, li_chain)
352 			if ((uid_t)kp->p_ppid == (uid_t)li->li_number)
353 				break;
354 		if (SLIST_FIRST(&ppidlist) != NULL && li == NULL) {
355 			selected[i] = 0;
356 			continue;
357 		}
358 
359 		SLIST_FOREACH(li, &pgrplist, li_chain)
360 			if (kp->p__pgid == (pid_t)li->li_number)
361 				break;
362 		if (SLIST_FIRST(&pgrplist) != NULL && li == NULL) {
363 			selected[i] = 0;
364 			continue;
365 		}
366 
367 		SLIST_FOREACH(li, &tdevlist, li_chain) {
368 			if (li->li_number == -1 &&
369 			    (kp->p_flag & P_CONTROLT) == 0)
370 				break;
371 			if (kp->p_tdev == (uid_t)li->li_number)
372 				break;
373 		}
374 		if (SLIST_FIRST(&tdevlist) != NULL && li == NULL) {
375 			selected[i] = 0;
376 			continue;
377 		}
378 
379 		SLIST_FOREACH(li, &sidlist, li_chain)
380 			if (kp->p_sid == (pid_t)li->li_number)
381 				break;
382 		if (SLIST_FIRST(&sidlist) != NULL && li == NULL) {
383 			selected[i] = 0;
384 			continue;
385 		}
386 
387 		if (argc == 0)
388 			selected[i] = 1;
389 	}
390 
391 	if (newest) {
392 		bestsec = 0;
393 		bestusec = 0;
394 		bestidx = -1;
395 
396 		for (i = 0, kp = plist; i < nproc; i++, kp++) {
397 			if (!selected[i])
398 				continue;
399 
400 			if (kp->p_ustart_sec > bestsec ||
401 			    (kp->p_ustart_sec == bestsec
402 			    && kp->p_ustart_usec > bestusec)) {
403 			    	bestsec = kp->p_ustart_sec;
404 			    	bestusec = kp->p_ustart_usec;
405 				bestidx = i;
406 			}
407 		}
408 
409 		(void)memset(selected, 0, (size_t)nproc);
410 		if (bestidx != -1)
411 			selected[bestidx] = 1;
412 	}
413 
414 	/*
415 	 * Take the appropriate action for each matched process, if any.
416 	 */
417 	for (i = 0, rv = 0, kp = plist; i < nproc; i++, kp++) {
418 		if (kp->p_pid == mypid)
419 			continue;
420 		if (selected[i]) {
421 			if (inverse)
422 				continue;
423 		} else if (!inverse)
424 			continue;
425 
426 		if ((kp->p_flag & P_SYSTEM) != 0)
427 			continue;
428 
429 		rv |= (*action)(kp);
430 	}
431 
432 	return rv ? STATUS_MATCH : STATUS_NOMATCH;
433 }
434 
435 static void
436 usage(void)
437 {
438 	const char *ustr;
439 
440 	if (prenice)
441 		fprintf(stderr, "Usage: %s [-l] priority pattern ...\n",
442 		    getprogname());
443 	else {
444 		if (pgrep)
445 			ustr = "[-filnvx] [-d delim]";
446 		else
447 			ustr = "[-signal] [-filnvx]";
448 
449 		(void)fprintf(stderr,
450 		    "Usage: %s %s [-G gid] [-g pgrp] [-P ppid] [-s sid] "
451 			   "[-t tty]\n"
452 		    "             [-U uid] [-u euid] pattern ...\n",
453 			      getprogname(), ustr);
454 	}
455 
456 	exit(STATUS_BADUSAGE);
457 }
458 
459 static int
460 killact(const struct kinfo_proc2 *kp)
461 {
462 	if (longfmt)
463 		grepact(kp);
464 	if (kill(kp->p_pid, signum) == -1) {
465 
466 		/*
467 		 * Check for ESRCH, which indicates that the process
468 		 * disappeared between us matching it and us
469 		 * signalling it; don't issue a warning about it.
470 		 */
471 		if (errno != ESRCH)
472 			warn("signalling pid %d", (int)kp->p_pid);
473 
474 		/*
475 		 * Return 0 to indicate that the process should not be
476 		 * considered a match, since we didn't actually get to
477 		 * signal it.
478 		 */
479 		return 0;
480 	}
481 
482 	return 1;
483 }
484 
485 static int
486 reniceact(const struct kinfo_proc2 *kp)
487 {
488 	int oldprio;
489 
490 	if (longfmt)
491 		grepact(kp);
492 
493 	errno = 0;
494 	if ((oldprio = getpriority(PRIO_PROCESS, kp->p_pid)) == -1 &&
495 	    errno != 0) {
496 		warn("%d: getpriority", kp->p_pid);
497 		return 0;
498 	}
499 
500 	if (setpriority(PRIO_PROCESS, kp->p_pid, nicenum) == -1) {
501 		warn("%d: setpriority", kp->p_pid);
502 		return 0;
503 	}
504 
505 	(void)printf("%d: old priority %d, new priority %d\n",
506 	    kp->p_pid, oldprio, nicenum);
507 
508 	return 1;
509 }
510 
511 static int
512 grepact(const struct kinfo_proc2 *kp)
513 {
514 	char **argv;
515 
516 	if (longfmt && matchargs) {
517 
518 		/*
519 		 * If kvm_getargv2() failed the process has probably
520 		 * disappeared.  Return 0 to indicate that the process
521 		 * should not be considered a match, since we are no
522 		 * longer in a position to output it as a match.
523 		 */
524 		if ((argv = kvm_getargv2(kd, kp, 0)) == NULL)
525 			return 0;
526 
527 		(void)printf("%d ", (int)kp->p_pid);
528 		for (; *argv != NULL; argv++) {
529 			(void)printf("%s", *argv);
530 			if (argv[1] != NULL)
531 				(void)putchar(' ');
532 		}
533 	} else if (longfmt)
534 		(void)printf("%d %s", (int)kp->p_pid, kp->p_comm);
535 	else
536 		(void)printf("%d", (int)kp->p_pid);
537 
538 	(void)printf("%s", delim);
539 
540 	return 1;
541 }
542 
543 static void
544 makelist(struct listhead *head, enum listtype type, char *src)
545 {
546 	struct list *li;
547 	struct passwd *pw;
548 	struct group *gr;
549 	struct stat st;
550 	char *sp, *ep, buf[MAXPATHLEN];
551 	const char *p;
552 	int empty;
553 	const char *prefix = _PATH_DEV;
554 
555 	empty = 1;
556 
557 	while ((sp = strsep(&src, ",")) != NULL) {
558 		if (*sp == '\0')
559 			usage();
560 
561 		if ((li = malloc(sizeof(*li))) == NULL)
562 			err(STATUS_ERROR, "Cannot allocate %zu bytes",
563 			    sizeof(*li));
564 		SLIST_INSERT_HEAD(head, li, li_chain);
565 		empty = 0;
566 
567 		li->li_number = (uid_t)strtol(sp, &ep, 0);
568 		if (*ep == '\0' && type != LT_TTY) {
569 			switch (type) {
570 			case LT_PGRP:
571 				if (li->li_number == 0)
572 					li->li_number = getpgrp();
573 				break;
574 			case LT_SID:
575 				if (li->li_number == 0)
576 					li->li_number = getsid(mypid);
577 				break;
578 			default:
579 				break;
580 			}
581 			continue;
582 		}
583 
584 		switch (type) {
585 		case LT_USER:
586 			if ((pw = getpwnam(sp)) == NULL)
587 				errx(STATUS_BADUSAGE, "Unknown user `%s'",
588 				    sp);
589 			li->li_number = pw->pw_uid;
590 			break;
591 		case LT_GROUP:
592 			if ((gr = getgrnam(sp)) == NULL)
593 				errx(STATUS_BADUSAGE, "Unknown group `%s'",
594 				    sp);
595 			li->li_number = gr->gr_gid;
596 			break;
597 		case LT_TTY:
598 			p = sp;
599 			if (*sp == '/')
600 				prefix = "";
601 			else if (strcmp(sp, "-") == 0) {
602 				li->li_number = -1;
603 				break;
604 			} else if (strcmp(sp, "co") == 0)
605 				p = "console";
606 			else if (strncmp(sp, "tty", 3) == 0)
607 				/* all set */;
608 			else if (strncmp(sp, "pts/", 4) == 0)
609 				/* all set */;
610 			else if (*ep != '\0' || (strlen(sp) == 2 && *sp == '0'))
611 				prefix = _PATH_TTY;
612 			else
613 				prefix = _PATH_DEV_PTS;
614 
615 			(void)snprintf(buf, sizeof(buf), "%s%s", prefix, p);
616 
617 			if (stat(buf, &st) == -1) {
618 				if (errno == ENOENT)
619 					errx(STATUS_BADUSAGE,
620 					    "No such tty: `%s'", buf);
621 				err(STATUS_ERROR, "Cannot access `%s'", buf);
622 			}
623 
624 			if ((st.st_mode & S_IFCHR) == 0)
625 				errx(STATUS_BADUSAGE, "Not a tty: `%s'", buf);
626 
627 			li->li_number = st.st_rdev;
628 			break;
629 		default:
630 			usage();
631 		}
632 	}
633 
634 	if (empty)
635 		usage();
636 }
637