xref: /openbsd/usr.bin/w/w.c (revision d89ec533)
1 /*	$OpenBSD: w.c,v 1.66 2019/06/28 13:35:05 deraadt Exp $	*/
2 
3 /*-
4  * Copyright (c) 1980, 1991, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * w - print system status (who and what)
34  *
35  * This program is similar to the systat command on Tenex/Tops 10/20
36  *
37  */
38 #include <sys/param.h>	/* MAXCOMLEN */
39 #include <sys/time.h>
40 #include <sys/stat.h>
41 #include <sys/sysctl.h>
42 #include <sys/signal.h>
43 #include <sys/proc.h>
44 #include <sys/ioctl.h>
45 #include <sys/socket.h>
46 #include <sys/tty.h>
47 
48 #include <netinet/in.h>
49 #include <arpa/inet.h>
50 
51 #include <ctype.h>
52 #include <err.h>
53 #include <errno.h>
54 #include <fcntl.h>
55 #include <kvm.h>
56 #include <netdb.h>
57 #include <nlist.h>
58 #include <paths.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <unistd.h>
63 #include <limits.h>
64 #include <utmp.h>
65 #include <vis.h>
66 
67 #include "extern.h"
68 
69 struct utmp	utmp;
70 struct winsize	ws;
71 kvm_t	       *kd;
72 time_t		now;		/* the current time of day */
73 int		ttywidth;	/* width of tty */
74 int		argwidth;	/* width of tty */
75 int		header = 1;	/* true if -h flag: don't print heading */
76 int		nflag = 1;	/* true if -n flag: don't convert addrs */
77 int		sortidle;	/* sort by idle time */
78 char	       *sel_user;	/* login of particular user selected */
79 char		domain[HOST_NAME_MAX+1];
80 
81 #define	NAME_WIDTH	8
82 #define HOST_WIDTH	16
83 
84 /*
85  * One of these per active utmp entry.
86  */
87 struct	entry {
88 	struct	entry *next;
89 	struct	utmp utmp;
90 	dev_t	tdev;			/* dev_t of terminal */
91 	time_t	idle;			/* idle time of terminal in seconds */
92 	struct	kinfo_proc *kp;		/* `most interesting' proc */
93 } *ep, *ehead = NULL, **nextp = &ehead;
94 
95 static void	 fmt_putc(int, int *);
96 static void	 fmt_puts(const char *, int *);
97 static void	 pr_args(struct kinfo_proc *);
98 static void	 pr_header(time_t *, int);
99 static struct stat
100 		*ttystat(char *);
101 static void	 usage(int);
102 
103 int
104 main(int argc, char *argv[])
105 {
106 	extern char *__progname;
107 	struct kinfo_proc *kp;
108 	struct hostent *hp;
109 	struct stat *stp;
110 	FILE *ut;
111 	struct in_addr addr;
112 	int ch, i, nentries, nusers, wcmd;
113 	char *memf, *nlistf, *p, *x;
114 	char buf[HOST_NAME_MAX+1], errbuf[_POSIX2_LINE_MAX];
115 
116 	/* Are we w(1) or uptime(1)? */
117 	p = __progname;
118 	if (*p == '-')
119 		p++;
120 	if (p[0] == 'w' && p[1] == '\0') {
121 		wcmd = 1;
122 		p = "hiflM:N:asuw";
123 	} else if (!strcmp(p, "uptime")) {
124 		wcmd = 0;
125 		p = "";
126 	} else
127 		errx(1,
128 		 "this program should be invoked only as \"w\" or \"uptime\"");
129 
130 	memf = nlistf = NULL;
131 	while ((ch = getopt(argc, argv, p)) != -1)
132 		switch (ch) {
133 		case 'h':
134 			header = 0;
135 			break;
136 		case 'i':
137 			sortidle = 1;
138 			break;
139 		case 'M':
140 			header = 0;
141 			memf = optarg;
142 			break;
143 		case 'N':
144 			nlistf = optarg;
145 			break;
146 		case 'a':
147 			nflag = 0;
148 			break;
149 		case 'f': case 'l': case 's': case 'u': case 'w':
150 			warnx("[-flsuw] no longer supported");
151 			/* FALLTHROUGH */
152 		case '?':
153 		default:
154 			usage(wcmd);
155 		}
156 	argc -= optind;
157 	argv += optind;
158 
159 	if (nflag == 0) {
160 		if (pledge("stdio tty rpath dns ps vminfo", NULL) == -1)
161 			err(1, "pledge");
162 	} else {
163 		if (pledge("stdio tty rpath ps vminfo", NULL) == -1)
164 			err(1, "pledge");
165 	}
166 
167 	if (nlistf == NULL && memf == NULL) {
168 		if ((kd = kvm_openfiles(nlistf, memf, NULL, KVM_NO_FILES,
169 		    errbuf)) == NULL)
170 			errx(1, "%s", errbuf);
171 	} else {
172 		if ((kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf)) == NULL)
173 			errx(1, "%s", errbuf);
174 	}
175 
176 	(void)time(&now);
177 	if ((ut = fopen(_PATH_UTMP, "r")) == NULL)
178 		err(1, "%s", _PATH_UTMP);
179 
180 	if (*argv)
181 		sel_user = *argv;
182 
183 	for (nusers = 0; fread(&utmp, sizeof(utmp), 1, ut);) {
184 		if (utmp.ut_name[0] == '\0')
185 			continue;
186 		++nusers;
187 		if (wcmd == 0 || (sel_user &&
188 		    strncmp(utmp.ut_name, sel_user, UT_NAMESIZE) != 0))
189 			continue;
190 		if ((ep = calloc(1, sizeof(*ep))) == NULL)
191 			err(1, NULL);
192 		*nextp = ep;
193 		nextp = &(ep->next);
194 		memcpy(&(ep->utmp), &utmp, sizeof(utmp));
195 		if (!(stp = ttystat(ep->utmp.ut_line)))
196 			continue;
197 		ep->tdev = stp->st_rdev;
198 
199 		/*
200 		 * If this is the console device, attempt to ascertain
201 		 * the true console device dev_t.
202 		 */
203 		if (ep->tdev == 0) {
204 			int mib[2];
205 			size_t size;
206 
207 			mib[0] = CTL_KERN;
208 			mib[1] = KERN_CONSDEV;
209 			size = sizeof(dev_t);
210 			(void) sysctl(mib, 2, &ep->tdev, &size, NULL, 0);
211 		}
212 
213 		if ((ep->idle = now - stp->st_atime) < 0)
214 			ep->idle = 0;
215 	}
216 	(void)fclose(ut);
217 
218 	if (header || wcmd == 0) {
219 		pr_header(&now, nusers);
220 		if (wcmd == 0)
221 			exit (0);
222 	}
223 
224 #define HEADER	"USER    TTY FROM              LOGIN@  IDLE WHAT"
225 #define WUSED	(sizeof(HEADER) - sizeof("WHAT"))
226 	if (header)
227 		(void)puts(HEADER);
228 
229 	kp = kvm_getprocs(kd, KERN_PROC_ALL, 0, sizeof(*kp), &nentries);
230 	if (kp == NULL)
231 		errx(1, "%s", kvm_geterr(kd));
232 
233 	if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 &&
234 	    ioctl(STDERR_FILENO, TIOCGWINSZ, &ws) == -1 &&
235 	    ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) == -1) || ws.ws_col == 0)
236 		ttywidth = 79;
237 	else
238 		ttywidth = ws.ws_col - 1;
239 	argwidth = ttywidth - WUSED;
240 	if (argwidth < 4)
241 		argwidth = 8;
242 
243 	for (i = 0; i < nentries; i++, kp++) {
244 		if (kp->p_psflags & (PS_EMBRYO | PS_ZOMBIE))
245 			continue;
246 		for (ep = ehead; ep != NULL; ep = ep->next) {
247 			/* ftp is a special case. */
248 			if (strncmp(ep->utmp.ut_line, "ftp", 3) == 0) {
249 				char pidstr[UT_LINESIZE-2];
250 				pid_t fp;
251 
252 				(void)strncpy(pidstr, &ep->utmp.ut_line[3],
253 				    sizeof(pidstr) - 1);
254 				pidstr[sizeof(pidstr) - 1] = '\0';
255 				fp = (pid_t)strtol(pidstr, NULL, 10);
256 				if (kp->p_pid == fp) {
257 					ep->kp = kp;
258 					break;
259 				}
260 			} else if (ep->tdev == kp->p_tdev &&
261 			    kp->p__pgid == kp->p_tpgid) {
262 				/*
263 				 * Proc is in foreground of this terminal
264 				 */
265 				if (proc_compare(ep->kp, kp))
266 					ep->kp = kp;
267 				break;
268 			}
269 		}
270 	}
271 	/* sort by idle time */
272 	if (sortidle && ehead != NULL) {
273 		struct entry *from = ehead, *save;
274 
275 		ehead = NULL;
276 		while (from != NULL) {
277 			for (nextp = &ehead;
278 			    (*nextp) && from->idle >= (*nextp)->idle;
279 			    nextp = &(*nextp)->next)
280 				continue;
281 			save = from;
282 			from = from->next;
283 			save->next = *nextp;
284 			*nextp = save;
285 		}
286 	}
287 
288 	if (!nflag) {
289 		if (gethostname(domain, sizeof(domain)) == -1 ||
290 		    (p = strchr(domain, '.')) == 0)
291 			domain[0] = '\0';
292 		else {
293 			domain[sizeof(domain) - 1] = '\0';
294 			memmove(domain, p, strlen(p) + 1);
295 		}
296 	}
297 
298 	for (ep = ehead; ep != NULL; ep = ep->next) {
299 		p = *ep->utmp.ut_host ? ep->utmp.ut_host : "-";
300 		for (x = NULL, i = 0; p[i] != '\0' && i < UT_HOSTSIZE; i++)
301 			if (p[i] == ':') {
302 				x = &p[i];
303 				*x++ = '\0';
304 				break;
305 			}
306 		if (!nflag && inet_aton(p, &addr) &&
307 		    (hp = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET))) {
308 			if (domain[0] != '\0') {
309 				p = hp->h_name;
310 				p += strlen(hp->h_name);
311 				p -= strlen(domain);
312 				if (p > hp->h_name &&
313 				    strcasecmp(p, domain) == 0)
314 					*p = '\0';
315 			}
316 			p = hp->h_name;
317 		}
318 		if (x) {
319 			(void)snprintf(buf, sizeof(buf), "%s:%.*s", p,
320 			    (int)(ep->utmp.ut_host + UT_HOSTSIZE - x), x);
321 			p = buf;
322 		}
323 		(void)printf("%-*.*s %-2.2s %-*.*s ",
324 		    NAME_WIDTH, UT_NAMESIZE, ep->utmp.ut_name,
325 		    strncmp(ep->utmp.ut_line, "tty", 3) ?
326 		    ep->utmp.ut_line : ep->utmp.ut_line + 3,
327 		    HOST_WIDTH, HOST_WIDTH, *p ? p : "-");
328 		pr_attime(&ep->utmp.ut_time, &now);
329 		pr_idle(ep->idle);
330 		pr_args(ep->kp);
331 		printf("\n");
332 	}
333 	exit(0);
334 }
335 
336 static void
337 fmt_putc(int c, int *leftp)
338 {
339 
340 	if (*leftp == 0)
341 		return;
342 	if (*leftp != -1)
343 		*leftp -= 1;
344 	putchar(c);
345 }
346 
347 static void
348 fmt_puts(const char *s, int *leftp)
349 {
350 	static char *v = NULL;
351 	static size_t maxlen = 0;
352 	size_t len;
353 
354 	if (*leftp == 0)
355 		return;
356 	len = strlen(s) * 4 + 1;
357 	if (len > maxlen) {
358 		free(v);
359 		maxlen = 0;
360 		if (len < getpagesize())
361 			len = getpagesize();
362 		v = malloc(len);
363 		if (v == NULL)
364 			return;
365 		maxlen = len;
366 	}
367 	strvis(v, s, VIS_TAB | VIS_NL | VIS_CSTYLE);
368 	if (*leftp != -1) {
369 		len = strlen(v);
370 		if (len > *leftp) {
371 			v[*leftp] = '\0';
372 			*leftp = 0;
373 		} else
374 			*leftp -= len;
375 	}
376 	printf("%s", v);
377 }
378 
379 
380 static void
381 pr_args(struct kinfo_proc *kp)
382 {
383 	char **argv, *str;
384 	int left;
385 
386 	if (kp == NULL)
387 		goto nothing;		/* no matching process found */
388 	left = argwidth;
389 	argv = kvm_getargv(kd, kp, argwidth+60);  /* +60 for ftpd snip */
390 	if (argv == NULL)
391 		goto nothing;
392 
393 	if (*argv == NULL || **argv == '\0') {
394 		/* Process has zeroed argv[0], display executable name. */
395 		fmt_putc('(', &left);
396 		fmt_puts(kp->p_comm, &left);
397 		fmt_putc(')', &left);
398 	}
399 	while (*argv) {
400 		/*
401 		 * ftp argv[0] is in the following format:
402 		 * ftpd: HOSTNAME: [USER/PASS: ]CMD args (ftpd)
403 		 */
404 		if (strncmp(*argv, "ftpd:", 5) == 0) {
405 			if ((str = strchr(*argv + 5, ':')) != NULL)
406 				str = strchr(str + 1, ':');
407 			if (str != NULL) {
408 				if ((str[0] == ':') &&
409 				    isspace((unsigned char)str[1]))
410 					str += 2;
411 				fmt_puts(str, &left);
412 			} else
413 				fmt_puts(*argv, &left);
414 		} else
415 			fmt_puts(*argv, &left);
416 		argv++;
417 		fmt_putc(' ', &left);
418 	}
419 	return;
420 nothing:
421 	putchar('-');
422 }
423 
424 static void
425 pr_header(time_t *nowp, int nusers)
426 {
427 	double avenrun[3];
428 	struct timespec boottime;
429 	time_t uptime;
430 	int days, hrs, i, mins;
431 	char buf[256];
432 
433 	/*
434 	 * Print time of day.
435 	 */
436 	(void)strftime(buf, sizeof(buf) - 1, "%l:%M%p", localtime(nowp));
437 	buf[sizeof(buf) - 1] = '\0';
438 	(void)printf("%s ", buf);
439 
440 	/*
441 	 * Print how long system has been up.
442 	 */
443 	if (clock_gettime(CLOCK_BOOTTIME, &boottime) != -1) {
444 		uptime = boottime.tv_sec;
445 		if (uptime > 59) {
446 			uptime += 30;
447 			days = uptime / SECSPERDAY;
448 			uptime %= SECSPERDAY;
449 			hrs = uptime / SECSPERHOUR;
450 			uptime %= SECSPERHOUR;
451 			mins = uptime / 60;
452 			(void)printf(" up");
453 			if (days > 0)
454 				(void)printf(" %d day%s,", days,
455 				    days > 1 ? "s" : "");
456 			if (hrs > 0 && mins > 0)
457 				(void)printf(" %2d:%02d,", hrs, mins);
458 			else {
459 				if (hrs > 0)
460 					(void)printf(" %d hr%s,",
461 					    hrs, hrs > 1 ? "s" : "");
462 				if (mins > 0 || (days == 0 && hrs == 0))
463 					(void)printf(" %d min%s,",
464 					    mins, mins != 1 ? "s" : "");
465 			}
466 		} else
467 			printf(" %d secs,", (int)uptime);
468 	}
469 
470 	/* Print number of users logged in to system */
471 	(void)printf(" %d user%s", nusers, nusers != 1 ? "s" : "");
472 
473 	/*
474 	 * Print 1, 5, and 15 minute load averages.
475 	 */
476 	if (getloadavg(avenrun, sizeof(avenrun) / sizeof(avenrun[0])) == -1)
477 		(void)printf(", no load average information available\n");
478 	else {
479 		(void)printf(", load averages:");
480 		for (i = 0; i < (sizeof(avenrun) / sizeof(avenrun[0])); i++) {
481 			if (i > 0)
482 				(void)printf(",");
483 			(void)printf(" %.2f", avenrun[i]);
484 		}
485 		(void)printf("\n");
486 	}
487 }
488 
489 static struct stat *
490 ttystat(char *line)
491 {
492 	static struct stat sb;
493 	char ttybuf[sizeof(_PATH_DEV) + UT_LINESIZE];
494 
495 	/* Note, line may not be NUL-terminated */
496 	(void)strlcpy(ttybuf, _PATH_DEV, sizeof(ttybuf));
497 	(void)strncat(ttybuf, line, sizeof(ttybuf) - 1 - strlen(ttybuf));
498 	if (stat(ttybuf, &sb))
499 		return (NULL);
500 	return (&sb);
501 }
502 
503 static void
504 usage(int wcmd)
505 {
506 	if (wcmd)
507 		(void)fprintf(stderr,
508 		    "usage: w [-ahi] [-M core] [-N system] [user]\n");
509 	else
510 		(void)fprintf(stderr,
511 		    "usage: uptime\n");
512 	exit (1);
513 }
514