pkill.c revision 164558 
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 * Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to The NetBSD Foundation
9 * by Andrew Doran.
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 NetBSD
22 *	Foundation, Inc. and its contributors.
23 * 4. Neither the name of The NetBSD Foundation nor the names of its
24 *    contributors may be used to endorse or promote products derived
25 *    from this software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37 * POSSIBILITY OF SUCH DAMAGE.
38 */
39
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD: head/usr.bin/pkill/pkill.c 164558 2006-11-23 11:55:17Z yar $");
42
43#include <sys/types.h>
44#include <sys/param.h>
45#include <sys/sysctl.h>
46#include <sys/proc.h>
47#include <sys/queue.h>
48#include <sys/stat.h>
49#include <sys/time.h>
50#include <sys/user.h>
51
52#include <stdio.h>
53#include <stdlib.h>
54#include <limits.h>
55#include <paths.h>
56#include <string.h>
57#include <unistd.h>
58#include <signal.h>
59#include <regex.h>
60#include <ctype.h>
61#include <fcntl.h>
62#include <kvm.h>
63#include <err.h>
64#include <pwd.h>
65#include <grp.h>
66#include <errno.h>
67#include <locale.h>
68
69#define	STATUS_MATCH	0
70#define	STATUS_NOMATCH	1
71#define	STATUS_BADUSAGE	2
72#define	STATUS_ERROR	3
73
74#define	MIN_PID	5
75#define	MAX_PID	99999
76
77/* Ignore system-processes (if '-S' flag is not specified) and myself. */
78#define	PSKIP(kp)	((kp)->ki_pid == mypid ||			\
79			 (!kthreads && ((kp)->ki_flag & P_KTHREAD) != 0))
80
81enum listtype {
82	LT_GENERIC,
83	LT_USER,
84	LT_GROUP,
85	LT_TTY,
86	LT_PGRP,
87	LT_JID,
88	LT_SID
89};
90
91struct list {
92	SLIST_ENTRY(list) li_chain;
93	long	li_number;
94};
95
96SLIST_HEAD(listhead, list);
97
98static struct kinfo_proc *plist;
99static char	*selected;
100static const char *delim = "\n";
101static int	nproc;
102static int	pgrep;
103static int	signum = SIGTERM;
104static int	newest;
105static int	oldest;
106static int	interactive;
107static int	inverse;
108static int	longfmt;
109static int	matchargs;
110static int	fullmatch;
111static int	kthreads;
112static int	cflags = REG_EXTENDED;
113static kvm_t	*kd;
114static pid_t	mypid;
115
116static struct listhead euidlist = SLIST_HEAD_INITIALIZER(list);
117static struct listhead ruidlist = SLIST_HEAD_INITIALIZER(list);
118static struct listhead rgidlist = SLIST_HEAD_INITIALIZER(list);
119static struct listhead pgrplist = SLIST_HEAD_INITIALIZER(list);
120static struct listhead ppidlist = SLIST_HEAD_INITIALIZER(list);
121static struct listhead tdevlist = SLIST_HEAD_INITIALIZER(list);
122static struct listhead sidlist = SLIST_HEAD_INITIALIZER(list);
123static struct listhead jidlist = SLIST_HEAD_INITIALIZER(list);
124
125static void	usage(void) __attribute__((__noreturn__));
126static int	killact(const struct kinfo_proc *);
127static int	grepact(const struct kinfo_proc *);
128static void	makelist(struct listhead *, enum listtype, char *);
129static int	takepid(const char *, int);
130
131int
132main(int argc, char **argv)
133{
134	char buf[_POSIX2_LINE_MAX], *mstr, **pargv, *p, *q, *pidfile;
135	const char *execf, *coref;
136	int debug_opt;
137	int i, ch, bestidx, rv, criteria, pidfromfile, pidfilelock;
138	size_t jsz;
139	int (*action)(const struct kinfo_proc *);
140	struct kinfo_proc *kp;
141	struct list *li;
142	struct timeval best_tval;
143	regex_t reg;
144	regmatch_t regmatch;
145
146	setlocale(LC_ALL, "");
147
148	if (strcmp(getprogname(), "pgrep") == 0) {
149		action = grepact;
150		pgrep = 1;
151	} else {
152		action = killact;
153		p = argv[1];
154
155		if (argc > 1 && p[0] == '-') {
156			p++;
157			i = (int)strtol(p, &q, 10);
158			if (*q == '\0') {
159				signum = i;
160				argv++;
161				argc--;
162			} else {
163				if (strncasecmp(p, "sig", 3) == 0)
164					p += 3;
165				for (i = 1; i < NSIG; i++)
166					if (strcasecmp(sys_signame[i], p) == 0)
167						break;
168				if (i != NSIG) {
169					signum = i;
170					argv++;
171					argc--;
172				}
173			}
174		}
175	}
176
177	criteria = 0;
178	debug_opt = 0;
179	pidfile = NULL;
180	pidfilelock = 0;
181	execf = coref = _PATH_DEVNULL;
182
183	while ((ch = getopt(argc, argv, "DF:G:ILM:N:P:SU:d:fg:ij:lnos:t:u:vx")) != -1)
184		switch (ch) {
185		case 'D':
186			debug_opt++;
187			break;
188		case 'F':
189			pidfile = optarg;
190			criteria = 1;
191			break;
192		case 'G':
193			makelist(&rgidlist, LT_GROUP, optarg);
194			criteria = 1;
195			break;
196		case 'I':
197			if (pgrep)
198				usage();
199			interactive = 1;
200			break;
201		case 'L':
202			pidfilelock = 1;
203			break;
204		case 'M':
205			coref = optarg;
206			break;
207		case 'N':
208			execf = optarg;
209			break;
210		case 'P':
211			makelist(&ppidlist, LT_GENERIC, optarg);
212			criteria = 1;
213			break;
214		case 'S':
215			if (!pgrep)
216				usage();
217			kthreads = 1;
218			break;
219		case 'U':
220			makelist(&ruidlist, LT_USER, optarg);
221			criteria = 1;
222			break;
223		case 'd':
224			if (!pgrep)
225				usage();
226			delim = optarg;
227			break;
228		case 'f':
229			matchargs = 1;
230			break;
231		case 'g':
232			makelist(&pgrplist, LT_PGRP, optarg);
233			criteria = 1;
234			break;
235		case 'i':
236			cflags |= REG_ICASE;
237			break;
238		case 'j':
239			makelist(&jidlist, LT_JID, optarg);
240			criteria = 1;
241			break;
242		case 'l':
243			if (!pgrep)
244				usage();
245			longfmt = 1;
246			break;
247		case 'n':
248			newest = 1;
249			criteria = 1;
250			break;
251		case 'o':
252			oldest = 1;
253			criteria = 1;
254			break;
255		case 's':
256			makelist(&sidlist, LT_SID, optarg);
257			criteria = 1;
258			break;
259		case 't':
260			makelist(&tdevlist, LT_TTY, optarg);
261			criteria = 1;
262			break;
263		case 'u':
264			makelist(&euidlist, LT_USER, optarg);
265			criteria = 1;
266			break;
267		case 'v':
268			inverse = 1;
269			break;
270		case 'x':
271			fullmatch = 1;
272			break;
273		default:
274			usage();
275			/* NOTREACHED */
276		}
277
278	argc -= optind;
279	argv += optind;
280	if (argc != 0)
281		criteria = 1;
282	if (!criteria)
283		usage();
284	if (newest && oldest)
285		errx(STATUS_ERROR, "Options -n and -o are mutually exclusive");
286	if (pidfile != NULL)
287		pidfromfile = takepid(pidfile, pidfilelock);
288	else {
289		if (pidfilelock) {
290			errx(STATUS_ERROR,
291			    "Option -L doesn't make sense without -F");
292		}
293		pidfromfile = -1;
294	}
295
296	mypid = getpid();
297
298	/*
299	 * Retrieve the list of running processes from the kernel.
300	 */
301	kd = kvm_openfiles(execf, coref, NULL, O_RDONLY, buf);
302	if (kd == NULL)
303		errx(STATUS_ERROR, "Cannot open kernel files (%s)", buf);
304
305	/*
306	 * Use KERN_PROC_PROC instead of KERN_PROC_ALL, since we
307	 * just want processes and not individual kernel threads.
308	 */
309	plist = kvm_getprocs(kd, KERN_PROC_PROC, 0, &nproc);
310	if (plist == NULL) {
311		errx(STATUS_ERROR, "Cannot get process list (%s)",
312		    kvm_geterr(kd));
313	}
314
315	/*
316	 * Allocate memory which will be used to keep track of the
317	 * selection.
318	 */
319	if ((selected = malloc(nproc)) == NULL) {
320		err(STATUS_ERROR, "Cannot allocate memory for %d processes",
321		    nproc);
322	}
323	memset(selected, 0, nproc);
324
325	/*
326	 * Refine the selection.
327	 */
328	for (; *argv != NULL; argv++) {
329		if ((rv = regcomp(&reg, *argv, cflags)) != 0) {
330			regerror(rv, &reg, buf, sizeof(buf));
331			errx(STATUS_BADUSAGE,
332			    "Cannot compile regular expression `%s' (%s)",
333			    *argv, buf);
334		}
335
336		for (i = 0, kp = plist; i < nproc; i++, kp++) {
337			if (PSKIP(kp)) {
338				if (debug_opt > 0)
339				    fprintf(stderr, "* Skipped %5d %3d %s\n",
340					kp->ki_pid, kp->ki_uid, kp->ki_comm);
341				continue;
342			}
343
344			if (matchargs &&
345			    (pargv = kvm_getargv(kd, kp, 0)) != NULL) {
346				jsz = 0;
347				while (jsz < sizeof(buf) && *pargv != NULL) {
348					jsz += snprintf(buf + jsz,
349					    sizeof(buf) - jsz,
350					    pargv[1] != NULL ? "%s " : "%s",
351					    pargv[0]);
352					pargv++;
353				}
354				mstr = buf;
355			} else
356				mstr = kp->ki_comm;
357
358			rv = regexec(&reg, mstr, 1, &regmatch, 0);
359			if (rv == 0) {
360				if (fullmatch) {
361					if (regmatch.rm_so == 0 &&
362					    regmatch.rm_eo ==
363					    (off_t)strlen(mstr))
364						selected[i] = 1;
365				} else
366					selected[i] = 1;
367			} else if (rv != REG_NOMATCH) {
368				regerror(rv, &reg, buf, sizeof(buf));
369				errx(STATUS_ERROR,
370				    "Regular expression evaluation error (%s)",
371				    buf);
372			}
373			if (debug_opt > 1) {
374				const char *rv_res = "NoMatch";
375				if (selected[i])
376					rv_res = "Matched";
377				fprintf(stderr, "* %s %5d %3d %s\n", rv_res,
378				    kp->ki_pid, kp->ki_uid, mstr);
379			}
380		}
381
382		regfree(&reg);
383	}
384
385	for (i = 0, kp = plist; i < nproc; i++, kp++) {
386		if (PSKIP(kp))
387			continue;
388
389		if (pidfromfile >= 0 && kp->ki_pid != pidfromfile) {
390			selected[i] = 0;
391			continue;
392		}
393
394		SLIST_FOREACH(li, &ruidlist, li_chain)
395			if (kp->ki_ruid == (uid_t)li->li_number)
396				break;
397		if (SLIST_FIRST(&ruidlist) != NULL && li == NULL) {
398			selected[i] = 0;
399			continue;
400		}
401
402		SLIST_FOREACH(li, &rgidlist, li_chain)
403			if (kp->ki_rgid == (gid_t)li->li_number)
404				break;
405		if (SLIST_FIRST(&rgidlist) != NULL && li == NULL) {
406			selected[i] = 0;
407			continue;
408		}
409
410		SLIST_FOREACH(li, &euidlist, li_chain)
411			if (kp->ki_uid == (uid_t)li->li_number)
412				break;
413		if (SLIST_FIRST(&euidlist) != NULL && li == NULL) {
414			selected[i] = 0;
415			continue;
416		}
417
418		SLIST_FOREACH(li, &ppidlist, li_chain)
419			if (kp->ki_ppid == (pid_t)li->li_number)
420				break;
421		if (SLIST_FIRST(&ppidlist) != NULL && li == NULL) {
422			selected[i] = 0;
423			continue;
424		}
425
426		SLIST_FOREACH(li, &pgrplist, li_chain)
427			if (kp->ki_pgid == (pid_t)li->li_number)
428				break;
429		if (SLIST_FIRST(&pgrplist) != NULL && li == NULL) {
430			selected[i] = 0;
431			continue;
432		}
433
434		SLIST_FOREACH(li, &tdevlist, li_chain) {
435			if (li->li_number == -1 &&
436			    (kp->ki_flag & P_CONTROLT) == 0)
437				break;
438			if (kp->ki_tdev == (dev_t)li->li_number)
439				break;
440		}
441		if (SLIST_FIRST(&tdevlist) != NULL && li == NULL) {
442			selected[i] = 0;
443			continue;
444		}
445
446		SLIST_FOREACH(li, &sidlist, li_chain)
447			if (kp->ki_sid == (pid_t)li->li_number)
448				break;
449		if (SLIST_FIRST(&sidlist) != NULL && li == NULL) {
450			selected[i] = 0;
451			continue;
452		}
453
454		SLIST_FOREACH(li, &jidlist, li_chain) {
455			/* A particular jail ID, including 0 (not in jail) */
456			if (kp->ki_jid == (int)li->li_number)
457				break;
458			/* Any jail */
459			if (kp->ki_jid > 0 && li->li_number == -1)
460				break;
461		}
462		if (SLIST_FIRST(&jidlist) != NULL && li == NULL) {
463			selected[i] = 0;
464			continue;
465		}
466
467		if (argc == 0)
468			selected[i] = 1;
469	}
470
471	if (newest || oldest) {
472		best_tval.tv_sec = 0;
473		best_tval.tv_usec = 0;
474		bestidx = -1;
475
476		for (i = 0, kp = plist; i < nproc; i++, kp++) {
477			if (!selected[i])
478				continue;
479			if (bestidx == -1) {
480				/* The first entry of the list which matched. */
481				;
482			} else if (timercmp(&kp->ki_start, &best_tval, >)) {
483				/* This entry is newer than previous "best". */
484				if (oldest)	/* but we want the oldest */
485					continue;
486			} else {
487				/* This entry is older than previous "best". */
488				if (newest)	/* but we want the newest */
489					continue;
490			}
491			/* This entry is better than previous "best" entry. */
492			best_tval.tv_sec = kp->ki_start.tv_sec;
493			best_tval.tv_usec = kp->ki_start.tv_usec;
494			bestidx = i;
495		}
496
497		memset(selected, 0, nproc);
498		if (bestidx != -1)
499			selected[bestidx] = 1;
500	}
501
502	/*
503	 * Take the appropriate action for each matched process, if any.
504	 */
505	for (i = 0, rv = 0, kp = plist; i < nproc; i++, kp++) {
506		if (PSKIP(kp))
507			continue;
508		if (selected[i]) {
509			if (inverse)
510				continue;
511		} else if (!inverse)
512			continue;
513		rv |= (*action)(kp);
514	}
515
516	exit(rv ? STATUS_MATCH : STATUS_NOMATCH);
517}
518
519static void
520usage(void)
521{
522	const char *ustr;
523
524	if (pgrep)
525		ustr = "[-LSfilnovx] [-d delim]";
526	else
527		ustr = "[-signal] [-ILfinovx]";
528
529	fprintf(stderr,
530		"usage: %s %s [-F pidfile] [-G gid] [-M core] [-N system]\n"
531		"             [-P ppid] [-U uid] [-g pgrp] [-j jid] [-s sid]\n"
532		"             [-t tty] [-u euid] pattern ...\n", getprogname(),
533		ustr);
534
535	exit(STATUS_BADUSAGE);
536}
537
538static void
539show_process(const struct kinfo_proc *kp)
540{
541	char **argv;
542
543	if ((longfmt || !pgrep) && matchargs &&
544	    (argv = kvm_getargv(kd, kp, 0)) != NULL) {
545		printf("%d ", (int)kp->ki_pid);
546		for (; *argv != NULL; argv++) {
547			printf("%s", *argv);
548			if (argv[1] != NULL)
549				putchar(' ');
550		}
551	} else if (longfmt || !pgrep)
552		printf("%d %s", (int)kp->ki_pid, kp->ki_comm);
553	else
554		printf("%d", (int)kp->ki_pid);
555}
556
557static int
558killact(const struct kinfo_proc *kp)
559{
560	int ch, first;
561
562	if (interactive) {
563		/*
564		 * Be careful, ask before killing.
565		 */
566		printf("kill ");
567		show_process(kp);
568		printf("? ");
569		fflush(stdout);
570		first = ch = getchar();
571		while (ch != '\n' && ch != EOF)
572			ch = getchar();
573		if (first != 'y' && first != 'Y')
574			return (1);
575	}
576	if (kill(kp->ki_pid, signum) == -1) {
577		/*
578		 * Check for ESRCH, which indicates that the process
579		 * disappeared between us matching it and us
580		 * signalling it; don't issue a warning about it.
581		 */
582		if (errno != ESRCH)
583			warn("signalling pid %d", (int)kp->ki_pid);
584		/*
585		 * Return 0 to indicate that the process should not be
586		 * considered a match, since we didn't actually get to
587		 * signal it.
588		 */
589		return (0);
590	}
591	return (1);
592}
593
594static int
595grepact(const struct kinfo_proc *kp)
596{
597
598	show_process(kp);
599	printf("%s", delim);
600	return (1);
601}
602
603static void
604makelist(struct listhead *head, enum listtype type, char *src)
605{
606	struct list *li;
607	struct passwd *pw;
608	struct group *gr;
609	struct stat st;
610	const char *cp, *prefix;
611	char *sp, *ep, buf[MAXPATHLEN];
612	int empty;
613
614	empty = 1;
615	prefix = _PATH_DEV;
616
617	while ((sp = strsep(&src, ",")) != NULL) {
618		if (*sp == '\0')
619			usage();
620
621		if ((li = malloc(sizeof(*li))) == NULL) {
622			err(STATUS_ERROR, "Cannot allocate %zu bytes",
623			    sizeof(*li));
624		}
625
626		SLIST_INSERT_HEAD(head, li, li_chain);
627		empty = 0;
628
629		li->li_number = (uid_t)strtol(sp, &ep, 0);
630		if (*ep == '\0') {
631			switch (type) {
632			case LT_PGRP:
633				if (li->li_number == 0)
634					li->li_number = getpgrp();
635				break;
636			case LT_SID:
637				if (li->li_number == 0)
638					li->li_number = getsid(mypid);
639				break;
640			case LT_JID:
641				if (li->li_number < 0)
642					errx(STATUS_BADUSAGE,
643					     "Negative jail ID `%s'", sp);
644				/* For compatibility with old -j */
645				if (li->li_number == 0)
646					li->li_number = -1;	/* any jail */
647				break;
648			case LT_TTY:
649				usage();
650				/* NOTREACHED */
651			default:
652				break;
653			}
654			continue;
655		}
656
657		switch (type) {
658		case LT_USER:
659			if ((pw = getpwnam(sp)) == NULL)
660				errx(STATUS_BADUSAGE, "Unknown user `%s'", sp);
661			li->li_number = pw->pw_uid;
662			break;
663		case LT_GROUP:
664			if ((gr = getgrnam(sp)) == NULL)
665				errx(STATUS_BADUSAGE, "Unknown group `%s'", sp);
666			li->li_number = gr->gr_gid;
667			break;
668		case LT_TTY:
669			if (strcmp(sp, "-") == 0) {
670				li->li_number = -1;
671				break;
672			} else if (strcmp(sp, "co") == 0) {
673				cp = "console";
674			} else {
675				cp = sp;
676				if (strncmp(sp, "tty", 3) != 0)
677					prefix = _PATH_TTY;
678			}
679
680			snprintf(buf, sizeof(buf), "%s%s", prefix, cp);
681
682			if (stat(buf, &st) == -1) {
683				if (errno == ENOENT) {
684					errx(STATUS_BADUSAGE,
685					    "No such tty: `%s'", sp);
686				}
687				err(STATUS_ERROR, "Cannot access `%s'", sp);
688			}
689
690			if ((st.st_mode & S_IFCHR) == 0)
691				errx(STATUS_BADUSAGE, "Not a tty: `%s'", sp);
692
693			li->li_number = st.st_rdev;
694			break;
695		case LT_JID:
696			if (strcmp(sp, "none") == 0)
697				li->li_number = 0;
698			else if (strcmp(sp, "any") == 0)
699				li->li_number = -1;
700			else if (*ep != '\0')
701				errx(STATUS_BADUSAGE,
702				     "Invalid jail ID `%s'", sp);
703			break;
704		default:
705			usage();
706		}
707	}
708
709	if (empty)
710		usage();
711}
712
713static int
714takepid(const char *pidfile, int pidfilelock)
715{
716	char *endp, line[BUFSIZ];
717	FILE *fh;
718	long rval;
719
720	fh = fopen(pidfile, "r");
721	if (fh == NULL)
722		err(STATUS_ERROR, "Cannot open pidfile `%s'", pidfile);
723
724	if (pidfilelock) {
725		/*
726		 * If we can lock pidfile, this means that daemon is not
727		 * running, so would be better not to kill some random process.
728		 */
729		if (flock(fileno(fh), LOCK_EX | LOCK_NB) == 0) {
730			(void)fclose(fh);
731			errx(STATUS_ERROR, "File '%s' can be locked", pidfile);
732		} else {
733			if (errno != EWOULDBLOCK) {
734				errx(STATUS_ERROR,
735				    "Error while locking file '%s'", pidfile);
736			}
737		}
738	}
739
740	if (fgets(line, sizeof(line), fh) == NULL) {
741		if (feof(fh)) {
742			(void)fclose(fh);
743			errx(STATUS_ERROR, "Pidfile `%s' is empty", pidfile);
744		}
745		(void)fclose(fh);
746		err(STATUS_ERROR, "Cannot read from pid file `%s'", pidfile);
747	}
748	(void)fclose(fh);
749
750	rval = strtol(line, &endp, 10);
751	if (*endp != '\0' && !isspace((unsigned char)*endp))
752		errx(STATUS_ERROR, "Invalid pid in file `%s'", pidfile);
753	else if (rval < MIN_PID || rval > MAX_PID)
754		errx(STATUS_ERROR, "Invalid pid in file `%s'", pidfile);
755	return (rval);
756}
757