xref: /netbsd-src/usr.bin/pkill/pkill.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: pkill.c,v 1.16 2005/10/10 22:13:20 kleink 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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #ifndef lint
41 __RCSID("$NetBSD: pkill.c,v 1.16 2005/10/10 22:13:20 kleink Exp $");
42 #endif /* !lint */
43 
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <sys/sysctl.h>
47 #include <sys/proc.h>
48 #include <sys/queue.h>
49 #include <sys/stat.h>
50 
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <limits.h>
54 #include <string.h>
55 #include <unistd.h>
56 #include <signal.h>
57 #include <regex.h>
58 #include <ctype.h>
59 #include <kvm.h>
60 #include <err.h>
61 #include <pwd.h>
62 #include <grp.h>
63 #include <errno.h>
64 #include <paths.h>
65 
66 #define	STATUS_MATCH	0
67 #define	STATUS_NOMATCH	1
68 #define	STATUS_BADUSAGE	2
69 #define	STATUS_ERROR	3
70 
71 enum listtype {
72 	LT_GENERIC,
73 	LT_USER,
74 	LT_GROUP,
75 	LT_TTY,
76 	LT_PGRP,
77 	LT_SID
78 };
79 
80 struct list {
81 	SLIST_ENTRY(list) li_chain;
82 	long	li_number;
83 };
84 
85 SLIST_HEAD(listhead, list);
86 
87 static struct kinfo_proc2	*plist;
88 static char	*selected;
89 static const char *delim = "\n";
90 static int	nproc;
91 static int	pgrep;
92 static int	signum = SIGTERM;
93 static int	newest;
94 static int	inverse;
95 static int	longfmt;
96 static int	matchargs;
97 static int	fullmatch;
98 static int	cflags = REG_EXTENDED;
99 static kvm_t	*kd;
100 static pid_t	mypid;
101 
102 static struct listhead euidlist = SLIST_HEAD_INITIALIZER(list);
103 static struct listhead ruidlist = SLIST_HEAD_INITIALIZER(list);
104 static struct listhead rgidlist = SLIST_HEAD_INITIALIZER(list);
105 static struct listhead pgrplist = SLIST_HEAD_INITIALIZER(list);
106 static struct listhead ppidlist = SLIST_HEAD_INITIALIZER(list);
107 static struct listhead tdevlist = SLIST_HEAD_INITIALIZER(list);
108 static struct listhead sidlist = SLIST_HEAD_INITIALIZER(list);
109 
110 int	main(int, char **);
111 static void	usage(void) __attribute__((__noreturn__));
112 static int	killact(const struct kinfo_proc2 *);
113 static int	grepact(const struct kinfo_proc2 *);
114 static void	makelist(struct listhead *, enum listtype, char *);
115 
116 int
117 main(int argc, char **argv)
118 {
119 	char buf[_POSIX2_LINE_MAX], **pargv, *q;
120 	int i, j, ch, bestidx, rv, criteria;
121 	int (*action)(const struct kinfo_proc2 *);
122 	const struct kinfo_proc2 *kp;
123 	struct list *li;
124 	const char *mstr, *p;
125 	u_int32_t bestsec, bestusec;
126 	regex_t reg;
127 	regmatch_t regmatch;
128 
129 	setprogname(argv[0]);
130 
131 	if (strcmp(getprogname(), "pgrep") == 0) {
132 		action = grepact;
133 		pgrep = 1;
134 	} else {
135 		action = killact;
136 		p = argv[1];
137 
138 		if (argc > 1 && p[0] == '-') {
139 			p++;
140 			i = (int)strtol(p, &q, 10);
141 			if (*q == '\0') {
142 				signum = i;
143 				argv++;
144 				argc--;
145 			} else {
146 				if (strncasecmp(p, "sig", 3) == 0)
147 					p += 3;
148 				for (i = 1; i < NSIG; i++)
149 					if (strcasecmp(sys_signame[i], p) == 0)
150 						break;
151 				if (i != NSIG) {
152 					signum = i;
153 					argv++;
154 					argc--;
155 				}
156 			}
157 		}
158 	}
159 
160 	criteria = 0;
161 
162 	while ((ch = getopt(argc, argv, "G:P:U:d:fg:ilns:t:u:vx")) != -1)
163 		switch (ch) {
164 		case 'G':
165 			makelist(&rgidlist, LT_GROUP, optarg);
166 			criteria = 1;
167 			break;
168 		case 'P':
169 			makelist(&ppidlist, LT_GENERIC, optarg);
170 			criteria = 1;
171 			break;
172 		case 'U':
173 			makelist(&ruidlist, LT_USER, optarg);
174 			criteria = 1;
175 			break;
176 		case 'd':
177 			if (!pgrep)
178 				usage();
179 			delim = optarg;
180 			break;
181 		case 'f':
182 			matchargs = 1;
183 			break;
184 		case 'g':
185 			makelist(&pgrplist, LT_PGRP, optarg);
186 			criteria = 1;
187 			break;
188 		case 'i':
189 			cflags |= REG_ICASE;
190 			break;
191 		case 'l':
192 			if (!pgrep)
193 				usage();
194 			longfmt = 1;
195 			break;
196 		case 'n':
197 			newest = 1;
198 			criteria = 1;
199 			break;
200 		case 's':
201 			makelist(&sidlist, LT_SID, optarg);
202 			criteria = 1;
203 			break;
204 		case 't':
205 			makelist(&tdevlist, LT_TTY, optarg);
206 			criteria = 1;
207 			break;
208 		case 'u':
209 			makelist(&euidlist, LT_USER, optarg);
210 			criteria = 1;
211 			break;
212 		case 'v':
213 			inverse = 1;
214 			break;
215 		case 'x':
216 			fullmatch = 1;
217 			break;
218 		default:
219 			usage();
220 			/* NOTREACHED */
221 		}
222 
223 	argc -= optind;
224 	argv += optind;
225 	if (argc != 0)
226 		criteria = 1;
227 	if (!criteria)
228 		usage();
229 
230 	mypid = getpid();
231 
232 	/*
233 	 * Retrieve the list of running processes from the kernel.
234 	 */
235 	kd = kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, buf);
236 	if (kd == NULL)
237 		errx(STATUS_ERROR, "Cannot open kernel files (%s)", buf);
238 
239 	plist = kvm_getproc2(kd, KERN_PROC_ALL, 0, sizeof(*plist), &nproc);
240 	if (plist == NULL)
241 		errx(STATUS_ERROR, "Cannot get process list (%s)",
242 		    kvm_geterr(kd));
243 
244 	/*
245 	 * Allocate memory which will be used to keep track of the
246 	 * selection.
247 	 */
248 	if ((selected = calloc((size_t)1, (size_t)nproc)) == NULL)
249 		err(STATUS_ERROR, "Cannot allocate memory for %d processes",
250 		    nproc);
251 
252 	/*
253 	 * Refine the selection.
254 	 */
255 	for (; *argv != NULL; argv++) {
256 		if ((rv = regcomp(&reg, *argv, cflags)) != 0) {
257 			(void)regerror(rv, &reg, buf, sizeof(buf));
258 			errx(STATUS_BADUSAGE,
259 			    "Cannot compile regular expression `%s' (%s)",
260 			    *argv, buf);
261 		}
262 
263 		for (i = 0, kp = plist; i < nproc; i++, kp++) {
264 			if ((kp->p_flag & P_SYSTEM) != 0 || kp->p_pid == mypid)
265 				continue;
266 
267 			if (matchargs) {
268 				if ((pargv = kvm_getargv2(kd, kp, 0)) == NULL)
269 					continue;
270 
271 				j = 0;
272 				while (j < sizeof(buf) && *pargv != NULL) {
273 					j += snprintf(buf + j, sizeof(buf) - j,
274 					    pargv[1] != NULL ? "%s " : "%s",
275 					    pargv[0]);
276 					pargv++;
277 				}
278 
279 				mstr = buf;
280 			} else
281 				mstr = kp->p_comm;
282 
283 			rv = regexec(&reg, mstr, 1, &regmatch, 0);
284 			if (rv == 0) {
285 				if (fullmatch) {
286 					if (regmatch.rm_so == 0 &&
287 					    regmatch.rm_eo == strlen(mstr))
288 						selected[i] = 1;
289 				} else
290 					selected[i] = 1;
291 			} else if (rv != REG_NOMATCH) {
292 				(void)regerror(rv, &reg, buf, sizeof(buf));
293 				errx(STATUS_ERROR,
294 				    "Regular expression evaluation error (%s)",
295 				    buf);
296 			}
297 		}
298 
299 		regfree(&reg);
300 	}
301 
302 	for (i = 0, kp = plist; i < nproc; i++, kp++) {
303 		if ((kp->p_flag & P_SYSTEM) != 0)
304 			continue;
305 
306 		SLIST_FOREACH(li, &ruidlist, li_chain)
307 			if (kp->p_ruid == (uid_t)li->li_number)
308 				break;
309 		if (SLIST_FIRST(&ruidlist) != NULL && li == NULL) {
310 			selected[i] = 0;
311 			continue;
312 		}
313 
314 		SLIST_FOREACH(li, &rgidlist, li_chain)
315 			if (kp->p_rgid == (gid_t)li->li_number)
316 				break;
317 		if (SLIST_FIRST(&rgidlist) != NULL && li == NULL) {
318 			selected[i] = 0;
319 			continue;
320 		}
321 
322 		SLIST_FOREACH(li, &euidlist, li_chain)
323 			if (kp->p_uid == (uid_t)li->li_number)
324 				break;
325 		if (SLIST_FIRST(&euidlist) != NULL && li == NULL) {
326 			selected[i] = 0;
327 			continue;
328 		}
329 
330 		SLIST_FOREACH(li, &ppidlist, li_chain)
331 			if (kp->p_ppid == (uid_t)li->li_number)
332 				break;
333 		if (SLIST_FIRST(&ppidlist) != NULL && li == NULL) {
334 			selected[i] = 0;
335 			continue;
336 		}
337 
338 		SLIST_FOREACH(li, &pgrplist, li_chain)
339 			if (kp->p__pgid == (uid_t)li->li_number)
340 				break;
341 		if (SLIST_FIRST(&pgrplist) != NULL && li == NULL) {
342 			selected[i] = 0;
343 			continue;
344 		}
345 
346 		SLIST_FOREACH(li, &tdevlist, li_chain) {
347 			if (li->li_number == -1 &&
348 			    (kp->p_flag & P_CONTROLT) == 0)
349 				break;
350 			if (kp->p_tdev == (uid_t)li->li_number)
351 				break;
352 		}
353 		if (SLIST_FIRST(&tdevlist) != NULL && li == NULL) {
354 			selected[i] = 0;
355 			continue;
356 		}
357 
358 		SLIST_FOREACH(li, &sidlist, li_chain)
359 			if (kp->p_sid == (uid_t)li->li_number)
360 				break;
361 		if (SLIST_FIRST(&sidlist) != NULL && li == NULL) {
362 			selected[i] = 0;
363 			continue;
364 		}
365 
366 		if (argc == 0)
367 			selected[i] = 1;
368 	}
369 
370 	if (newest) {
371 		bestsec = 0;
372 		bestusec = 0;
373 		bestidx = -1;
374 
375 		for (i = 0, kp = plist; i < nproc; i++, kp++) {
376 			if (!selected[i])
377 				continue;
378 
379 			if (kp->p_ustart_sec > bestsec ||
380 			    (kp->p_ustart_sec == bestsec
381 			    && kp->p_ustart_usec > bestusec)) {
382 			    	bestsec = kp->p_ustart_sec;
383 			    	bestusec = kp->p_ustart_usec;
384 				bestidx = i;
385 			}
386 		}
387 
388 		(void)memset(selected, 0, (size_t)nproc);
389 		if (bestidx != -1)
390 			selected[bestidx] = 1;
391 	}
392 
393 	/*
394 	 * Take the appropriate action for each matched process, if any.
395 	 */
396 	for (i = 0, rv = 0, kp = plist; i < nproc; i++, kp++) {
397 		if (kp->p_pid == mypid)
398 			continue;
399 		if (selected[i]) {
400 			if (inverse)
401 				continue;
402 		} else if (!inverse)
403 			continue;
404 
405 		if ((kp->p_flag & P_SYSTEM) != 0)
406 			continue;
407 
408 		rv |= (*action)(kp);
409 	}
410 
411 	return rv ? STATUS_MATCH : STATUS_NOMATCH;
412 }
413 
414 static void
415 usage(void)
416 {
417 	const char *ustr;
418 
419 	if (pgrep)
420 		ustr = "[-filnvx] [-d delim]";
421 	else
422 		ustr = "[-signal] [-finvx]";
423 
424 	(void)fprintf(stderr,
425 		"Usage: %s %s [-G gid] [-P ppid] [-U uid] [-g pgrp] [-s sid]\n"
426 		"             [-t tty] [-u euid] pattern ...\n", getprogname(),
427 		ustr);
428 
429 	exit(STATUS_BADUSAGE);
430 }
431 
432 static int
433 killact(const struct kinfo_proc2 *kp)
434 {
435 	if (kill(kp->p_pid, signum) == -1) {
436 
437 		/*
438 		 * Check for ESRCH, which indicates that the process
439 		 * disappeared between us matching it and us
440 		 * signalling it; don't issue a warning about it.
441 		 */
442 		if (errno != ESRCH)
443 			warn("signalling pid %d", (int)kp->p_pid);
444 
445 		/*
446 		 * Return 0 to indicate that the process should not be
447 		 * considered a match, since we didn't actually get to
448 		 * signal it.
449 		 */
450 		return 0;
451 	}
452 
453 	return 1;
454 }
455 
456 static int
457 grepact(const struct kinfo_proc2 *kp)
458 {
459 	char **argv;
460 
461 	if (longfmt && matchargs) {
462 
463 		/*
464 		 * If kvm_getargv2() failed the process has probably
465 		 * disappeared.  Return 0 to indicate that the process
466 		 * should not be considered a match, since we are no
467 		 * longer in a position to output it as a match.
468 		 */
469 		if ((argv = kvm_getargv2(kd, kp, 0)) == NULL)
470 			return 0;
471 
472 		(void)printf("%d ", (int)kp->p_pid);
473 		for (; *argv != NULL; argv++) {
474 			(void)printf("%s", *argv);
475 			if (argv[1] != NULL)
476 				(void)putchar(' ');
477 		}
478 	} else if (longfmt)
479 		(void)printf("%d %s", (int)kp->p_pid, kp->p_comm);
480 	else
481 		(void)printf("%d", (int)kp->p_pid);
482 
483 	(void)printf("%s", delim);
484 
485 	return 1;
486 }
487 
488 static void
489 makelist(struct listhead *head, enum listtype type, char *src)
490 {
491 	struct list *li;
492 	struct passwd *pw;
493 	struct group *gr;
494 	struct stat st;
495 	char *sp, *ep, buf[MAXPATHLEN];
496 	const char *p;
497 	int empty;
498 	const char *prefix = _PATH_DEV;
499 
500 	empty = 1;
501 
502 	while ((sp = strsep(&src, ",")) != NULL) {
503 		if (*sp == '\0')
504 			usage();
505 
506 		if ((li = malloc(sizeof(*li))) == NULL)
507 			err(STATUS_ERROR, "Cannot allocate %zd bytes",
508 			    sizeof(*li));
509 		SLIST_INSERT_HEAD(head, li, li_chain);
510 		empty = 0;
511 
512 		li->li_number = (uid_t)strtol(sp, &ep, 0);
513 		if (*ep == '\0') {
514 			switch (type) {
515 			case LT_PGRP:
516 				if (li->li_number == 0)
517 					li->li_number = getpgrp();
518 				break;
519 			case LT_SID:
520 				if (li->li_number == 0)
521 					li->li_number = getsid(mypid);
522 				break;
523 			case LT_TTY:
524 				usage();
525 				/*NOTREACHED*/
526 			default:
527 				break;
528 			}
529 			continue;
530 		}
531 
532 		switch (type) {
533 		case LT_USER:
534 			if ((pw = getpwnam(sp)) == NULL)
535 				errx(STATUS_BADUSAGE, "Unknown user `%s'",
536 				    sp);
537 			li->li_number = pw->pw_uid;
538 			break;
539 		case LT_GROUP:
540 			if ((gr = getgrnam(sp)) == NULL)
541 				errx(STATUS_BADUSAGE, "Unknown group `%s'",
542 				    sp);
543 			li->li_number = gr->gr_gid;
544 			break;
545 		case LT_TTY:
546 			if (strcmp(sp, "-") == 0) {
547 				li->li_number = -1;
548 				break;
549 			} else if (strcmp(sp, "co") == 0)
550 				p = "console";
551 			else if (strncmp(sp, "tty", 3) == 0)
552 				p = sp;
553 			else {
554 				p = sp;
555 				prefix = _PATH_TTY;
556 			}
557 
558 			(void)snprintf(buf, sizeof(buf), "%s%s", prefix, p);
559 
560 			if (stat(buf, &st) == -1) {
561 				if (errno == ENOENT)
562 					errx(STATUS_BADUSAGE,
563 					    "No such tty: `%s'", sp);
564 				err(STATUS_ERROR, "Cannot access `%s'", sp);
565 			}
566 
567 			if ((st.st_mode & S_IFCHR) == 0)
568 				errx(STATUS_BADUSAGE, "Not a tty: `%s'", sp);
569 
570 			li->li_number = st.st_rdev;
571 			break;
572 		default:
573 			usage();
574 		}
575 	}
576 
577 	if (empty)
578 		usage();
579 }
580