pkill.c revision 127472 
1/*	$NetBSD: pkill.c,v 1.7 2004/02/15 17:03:30 soren 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__FBSDID("$FreeBSD: head/usr.bin/pkill/pkill.c 127472 2004-03-27 06:49:57Z gad $");
41
42#include <sys/types.h>
43#include <sys/param.h>
44#include <sys/sysctl.h>
45#include <sys/proc.h>
46#include <sys/queue.h>
47#include <sys/stat.h>
48#include <sys/user.h>
49
50#include <stdio.h>
51#include <stdlib.h>
52#include <limits.h>
53#include <paths.h>
54#include <string.h>
55#include <unistd.h>
56#include <signal.h>
57#include <regex.h>
58#include <ctype.h>
59#include <fcntl.h>
60#include <kvm.h>
61#include <err.h>
62#include <pwd.h>
63#include <grp.h>
64#include <errno.h>
65
66#define	STATUS_MATCH	0
67#define	STATUS_NOMATCH	1
68#define	STATUS_BADUSAGE	2
69#define	STATUS_ERROR	3
70
71/* Check for system-processes which should always be ignored. */
72#define	IS_KERNPROC(kp)	((kp)->ki_flag & P_KTHREAD)
73
74enum listtype {
75	LT_GENERIC,
76	LT_USER,
77	LT_GROUP,
78	LT_TTY,
79	LT_PGRP,
80	LT_SID
81};
82
83struct list {
84	SLIST_ENTRY(list) li_chain;
85	long	li_number;
86};
87
88SLIST_HEAD(listhead, list);
89
90struct kinfo_proc	*plist;
91char	*selected;
92const char	*delim = "\n";
93int	nproc;
94int	pgrep;
95int	signum = SIGTERM;
96int	newest;
97int	inverse;
98int	longfmt;
99int	matchargs;
100int	fullmatch;
101kvm_t	*kd;
102pid_t	mypid;
103
104struct listhead euidlist = SLIST_HEAD_INITIALIZER(list);
105struct listhead ruidlist = SLIST_HEAD_INITIALIZER(list);
106struct listhead rgidlist = SLIST_HEAD_INITIALIZER(list);
107struct listhead pgrplist = SLIST_HEAD_INITIALIZER(list);
108struct listhead ppidlist = SLIST_HEAD_INITIALIZER(list);
109struct listhead tdevlist = SLIST_HEAD_INITIALIZER(list);
110struct listhead sidlist = SLIST_HEAD_INITIALIZER(list);
111
112int	main(int, char **);
113void	usage(void);
114void	killact(struct kinfo_proc *);
115void	grepact(struct kinfo_proc *);
116void	makelist(struct listhead *, enum listtype, char *);
117
118int
119main(int argc, char **argv)
120{
121	extern char *optarg;
122	extern int optind;
123	char buf[_POSIX2_LINE_MAX], *mstr, **pargv, *p, *q;
124	const char *execf, *coref;
125	int debug_opt;
126	int i, ch, bestidx, rv, criteria, drop_privs;
127	size_t jsz;
128	void (*action)(struct kinfo_proc *);
129	struct kinfo_proc *kp;
130	struct list *li;
131	struct timeval best_tval;
132	regex_t reg;
133	regmatch_t regmatch;
134
135	if (strcmp(getprogname(), "pgrep") == 0) {
136		action = grepact;
137		pgrep = 1;
138	} else {
139		action = killact;
140		p = argv[1];
141
142		if (argc > 1 && p[0] == '-') {
143			p++;
144			i = (int)strtol(p, &q, 10);
145			if (*q == '\0') {
146				signum = i;
147				argv++;
148				argc--;
149			} else {
150				if (strncasecmp(p, "sig", 3) == 0)
151					p += 3;
152				for (i = 1; i < NSIG; i++)
153					if (strcasecmp(sys_signame[i], p) == 0)
154						break;
155				if (i != NSIG) {
156					signum = i;
157					argv++;
158					argc--;
159				}
160			}
161		}
162	}
163
164	criteria = 0;
165	debug_opt = 0;
166	drop_privs = 0;
167	execf = coref = _PATH_DEVNULL;
168
169	while ((ch = getopt(argc, argv, "DG:M:N:P:U:d:fg:lns:t:u:vx")) != -1)
170		switch (ch) {
171		case 'D':
172			debug_opt++;
173			break;
174		case 'G':
175			makelist(&rgidlist, LT_GROUP, optarg);
176			criteria = 1;
177			break;
178		case 'M':
179			coref = optarg;
180			drop_privs = 1;
181			break;
182		case 'N':
183			execf = optarg;
184			drop_privs = 1;
185			break;
186		case 'P':
187			makelist(&ppidlist, LT_GENERIC, optarg);
188			criteria = 1;
189			break;
190		case 'U':
191			makelist(&ruidlist, LT_USER, optarg);
192			criteria = 1;
193			break;
194		case 'd':
195			if (!pgrep)
196				usage();
197			delim = optarg;
198			break;
199		case 'f':
200			matchargs = 1;
201			break;
202		case 'g':
203			makelist(&pgrplist, LT_PGRP, optarg);
204			criteria = 1;
205			break;
206		case 'l':
207			if (!pgrep)
208				usage();
209			longfmt = 1;
210			break;
211		case 'n':
212			newest = 1;
213			criteria = 1;
214			break;
215		case 's':
216			makelist(&sidlist, LT_SID, optarg);
217			criteria = 1;
218			break;
219		case 't':
220			makelist(&tdevlist, LT_TTY, optarg);
221			criteria = 1;
222			break;
223		case 'u':
224			makelist(&euidlist, LT_USER, optarg);
225			criteria = 1;
226			break;
227		case 'v':
228			inverse = 1;
229			break;
230		case 'x':
231			fullmatch = 1;
232			break;
233		default:
234			usage();
235			/* NOTREACHED */
236		}
237
238	argc -= optind;
239	argv += optind;
240	if (argc != 0)
241		criteria = 1;
242	if (!criteria)
243		usage();
244
245	/*
246	 * Discard privileges if not the running kernel so that bad
247	 * guys can't print interesting stuff from kernel memory.
248	 */
249	if (drop_privs) {
250		setgid(getgid());
251		setuid(getuid());
252	}
253
254	mypid = getpid();
255
256	/*
257	 * Retrieve the list of running processes from the kernel.
258	 */
259	kd = kvm_openfiles(execf, coref, NULL, O_RDONLY, buf);
260	if (kd == NULL)
261		errx(STATUS_ERROR, "kvm_openfiles(): %s", buf);
262
263	plist = kvm_getprocs(kd, KERN_PROC_ALL, 0, &nproc);
264	if (plist == NULL)
265		errx(STATUS_ERROR, "kvm_getprocs() failed");
266
267	/*
268	 * Allocate memory which will be used to keep track of the
269	 * selection.
270	 */
271	if ((selected = malloc(nproc)) == NULL)
272		errx(STATUS_ERROR, "memory allocation failure");
273	memset(selected, 0, nproc);
274
275	/*
276	 * Refine the selection.
277	 */
278	for (; *argv != NULL; argv++) {
279		if ((rv = regcomp(&reg, *argv, REG_EXTENDED)) != 0) {
280			regerror(rv, &reg, buf, sizeof(buf));
281			errx(STATUS_BADUSAGE, "bad expression: %s", buf);
282		}
283
284		for (i = 0, kp = plist; i < nproc; i++, kp++) {
285			if (IS_KERNPROC(kp) != 0) {
286				if (debug_opt > 0)
287				    fprintf(stderr, "* Skipped %5d %3d %s\n",
288					kp->ki_pid, kp->ki_uid, kp->ki_comm);
289				continue;
290			}
291
292			if (matchargs) {
293				if ((pargv = kvm_getargv(kd, kp, 0)) == NULL)
294					continue;
295
296				jsz = 0;
297				while (jsz < sizeof(buf) && *pargv != NULL) {
298					jsz += snprintf(buf + jsz,
299					    sizeof(buf) - jsz,
300					    pargv[1] != NULL ? "%s " : "%s",
301					    pargv[0]);
302					pargv++;
303				}
304
305				mstr = buf;
306			} else
307				mstr = kp->ki_comm;
308
309			rv = regexec(&reg, mstr, 1, &regmatch, 0);
310			if (rv == 0) {
311				if (fullmatch) {
312					if (regmatch.rm_so == 0 &&
313					    regmatch.rm_eo ==
314					    (off_t)strlen(mstr))
315						selected[i] = 1;
316				} else
317					selected[i] = 1;
318			} else if (rv != REG_NOMATCH) {
319				regerror(rv, &reg, buf, sizeof(buf));
320				errx(STATUS_ERROR, "regexec(): %s", buf);
321			}
322			if (debug_opt > 1) {
323				const char *rv_res = "NoMatch";
324				if (selected[i])
325					rv_res = "Matched";
326				fprintf(stderr, "* %s %5d %3d %s\n", rv_res,
327				    kp->ki_pid, kp->ki_uid, mstr);
328			}
329		}
330
331		regfree(&reg);
332	}
333
334	for (i = 0, kp = plist; i < nproc; i++, kp++) {
335		if (IS_KERNPROC(kp) != 0)
336			continue;
337
338		SLIST_FOREACH(li, &ruidlist, li_chain)
339			if (kp->ki_ruid == (uid_t)li->li_number)
340				break;
341		if (SLIST_FIRST(&ruidlist) != NULL && li == NULL) {
342			selected[i] = 0;
343			continue;
344		}
345
346		SLIST_FOREACH(li, &rgidlist, li_chain)
347			if (kp->ki_rgid == (gid_t)li->li_number)
348				break;
349		if (SLIST_FIRST(&rgidlist) != NULL && li == NULL) {
350			selected[i] = 0;
351			continue;
352		}
353
354		SLIST_FOREACH(li, &euidlist, li_chain)
355			if (kp->ki_uid == (uid_t)li->li_number)
356				break;
357		if (SLIST_FIRST(&euidlist) != NULL && li == NULL) {
358			selected[i] = 0;
359			continue;
360		}
361
362		SLIST_FOREACH(li, &ppidlist, li_chain)
363			if (kp->ki_ppid == (pid_t)li->li_number)
364				break;
365		if (SLIST_FIRST(&ppidlist) != NULL && li == NULL) {
366			selected[i] = 0;
367			continue;
368		}
369
370		SLIST_FOREACH(li, &pgrplist, li_chain)
371			if (kp->ki_pgid == (pid_t)li->li_number)
372				break;
373		if (SLIST_FIRST(&pgrplist) != NULL && li == NULL) {
374			selected[i] = 0;
375			continue;
376		}
377
378		SLIST_FOREACH(li, &tdevlist, li_chain) {
379			if (li->li_number == -1 &&
380			    (kp->ki_flag & P_CONTROLT) == 0)
381				break;
382			if (kp->ki_tdev == (udev_t)li->li_number)
383				break;
384		}
385		if (SLIST_FIRST(&tdevlist) != NULL && li == NULL) {
386			selected[i] = 0;
387			continue;
388		}
389
390		SLIST_FOREACH(li, &sidlist, li_chain)
391			if (kp->ki_sid == (pid_t)li->li_number)
392				break;
393		if (SLIST_FIRST(&sidlist) != NULL && li == NULL) {
394			selected[i] = 0;
395			continue;
396		}
397
398		if (argc == 0)
399			selected[i] = 1;
400	}
401
402	if (newest) {
403		best_tval.tv_sec = 0;
404		best_tval.tv_usec = 0;
405		bestidx = -1;
406
407		for (i = 0, kp = plist; i < nproc; i++, kp++) {
408			if (!selected[i])
409				continue;
410
411			if (kp->ki_start.tv_sec > best_tval.tv_sec ||
412			    (kp->ki_start.tv_sec == best_tval.tv_sec
413			    && kp->ki_start.tv_usec > best_tval.tv_usec)) {
414				best_tval.tv_sec = kp->ki_start.tv_sec;
415				best_tval.tv_usec = kp->ki_start.tv_usec;
416				bestidx = i;
417			}
418		}
419
420		memset(selected, 0, nproc);
421		if (bestidx != -1)
422			selected[bestidx] = 1;
423	}
424
425	/*
426	 * Take the appropriate action for each matched process, if any.
427	 */
428	for (i = 0, rv = 0, kp = plist; i < nproc; i++, kp++) {
429		if (kp->ki_pid == mypid)
430			continue;
431		if (selected[i]) {
432			if (inverse)
433				continue;
434		} else if (!inverse)
435			continue;
436
437		if (IS_KERNPROC(kp) != 0)
438			continue;
439
440		rv = 1;
441		(*action)(kp);
442	}
443
444	exit(rv ? STATUS_MATCH : STATUS_NOMATCH);
445}
446
447void
448usage(void)
449{
450	const char *ustr;
451
452	if (pgrep)
453		ustr = "[-flnvx] [-d delim]";
454	else
455		ustr = "[-signal] [-fnvx]";
456
457	fprintf(stderr,
458		"usage: %s %s [-G gid] [-M core] [-N system]\n"
459		"             [-P ppid] [-U uid] [-g pgrp] [-s sid] [-t tty]\n"
460		"             [-u euid] pattern ...\n", getprogname(), ustr);
461
462	exit(STATUS_ERROR);
463}
464
465void
466killact(struct kinfo_proc *kp)
467{
468
469	if (kill(kp->ki_pid, signum) == -1)
470		err(STATUS_ERROR, "signalling pid %d", (int)kp->ki_pid);
471}
472
473void
474grepact(struct kinfo_proc *kp)
475{
476	char **argv;
477
478	if (longfmt && matchargs) {
479		if ((argv = kvm_getargv(kd, kp, 0)) == NULL)
480			return;
481
482		printf("%d ", (int)kp->ki_pid);
483		for (; *argv != NULL; argv++) {
484			printf("%s", *argv);
485			if (argv[1] != NULL)
486				putchar(' ');
487		}
488	} else if (longfmt)
489		printf("%d %s", (int)kp->ki_pid, kp->ki_comm);
490	else
491		printf("%d", (int)kp->ki_pid);
492
493	printf("%s", delim);
494}
495
496void
497makelist(struct listhead *head, enum listtype type, char *src)
498{
499	struct list *li;
500	struct passwd *pw;
501	struct group *gr;
502	struct stat st;
503	const char *cp;
504	char *sp, *p, buf[MAXPATHLEN];
505	int empty;
506
507	empty = 1;
508
509	while ((sp = strsep(&src, ",")) != NULL) {
510		if (*sp == '\0')
511			usage();
512
513		if ((li = malloc(sizeof(*li))) == NULL)
514			errx(STATUS_ERROR, "memory allocation failure");
515		SLIST_INSERT_HEAD(head, li, li_chain);
516		empty = 0;
517
518		li->li_number = (uid_t)strtol(sp, &p, 0);
519		if (*p == '\0') {
520			switch (type) {
521			case LT_PGRP:
522				if (li->li_number == 0)
523					li->li_number = getpgrp();
524				break;
525			case LT_SID:
526				if (li->li_number == 0)
527					li->li_number = getsid(mypid);
528				break;
529			case LT_TTY:
530				usage();
531			default:
532				break;
533			}
534			continue;
535		}
536
537		switch (type) {
538		case LT_USER:
539			if ((pw = getpwnam(sp)) == NULL)
540				errx(STATUS_BADUSAGE, "unknown user `%s'",
541				    optarg);
542			li->li_number = pw->pw_uid;
543			break;
544		case LT_GROUP:
545			if ((gr = getgrnam(sp)) == NULL)
546				errx(STATUS_BADUSAGE, "unknown group `%s'",
547				    optarg);
548			li->li_number = gr->gr_gid;
549			break;
550		case LT_TTY:
551			if (strcmp(sp, "-") == 0) {
552				li->li_number = -1;
553				break;
554			} else if (strcmp(sp, "co") == 0)
555				cp = "console";
556			else if (strncmp(sp, "tty", 3) == 0)
557				cp = sp;
558			else
559				cp = NULL;
560
561			if (cp == NULL)
562				snprintf(buf, sizeof(buf), "/dev/tty%s", sp);
563			else
564				snprintf(buf, sizeof(buf), "/dev/%s", cp);
565
566			if (stat(buf, &st) < 0) {
567				if (errno == ENOENT)
568					errx(STATUS_BADUSAGE,
569					    "no such tty: `%s'", sp);
570				err(STATUS_ERROR, "stat(%s)", sp);
571			}
572
573			if ((st.st_mode & S_IFCHR) == 0)
574				errx(STATUS_BADUSAGE, "not a tty: `%s'", sp);
575
576			li->li_number = st.st_rdev;
577			break;
578		default:
579			usage();
580		};
581	}
582
583	if (empty)
584		usage();
585}
586