xref: /freebsd/usr.bin/rwho/rwho.c (revision 389e4940069316fe667ffa263fa7d6390d0a960f)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993 The Regents of the University of California.
5  * Copyright (c) 2013 Mariusz Zaborski <oshogbo@FreeBSD.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef lint
34 static const char copyright[] =
35 "@(#) Copyright (c) 1983, 1993\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif /* not lint */
38 
39 #ifndef lint
40 #if 0
41 static char sccsid[] = "@(#)rwho.c	8.1 (Berkeley) 6/6/93";
42 #endif
43 #endif /* not lint */
44 
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 #include <sys/capsicum.h>
49 #include <sys/param.h>
50 #include <sys/file.h>
51 
52 #include <protocols/rwhod.h>
53 
54 #include <dirent.h>
55 #include <err.h>
56 #include <errno.h>
57 #include <langinfo.h>
58 #include <locale.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <time.h>
63 #include <timeconv.h>
64 #include <unistd.h>
65 
66 #define	NUSERS		1000
67 #define	WHDRSIZE	(ssize_t)(sizeof(wd) - sizeof(wd.wd_we))
68 /*
69  * this macro should be shared with ruptime.
70  */
71 #define	down(w,now)	((now) - (w)->wd_recvtime > 11 * 60)
72 
73 static DIR	*dirp;
74 static struct	whod wd;
75 static int	nusers;
76 static struct	myutmp {
77 	char    myhost[sizeof(wd.wd_hostname)];
78 	int	myidle;
79 	struct	outmp myutmp;
80 } myutmp[NUSERS];
81 
82 static time_t	now;
83 static int	aflg;
84 
85 static void usage(void);
86 static int utmpcmp(const void *, const void *);
87 
88 int
89 main(int argc, char *argv[])
90 {
91 	int ch;
92 	struct dirent *dp;
93 	int width;
94 	ssize_t cc;
95 	struct whod *w;
96 	struct whoent *we;
97 	struct myutmp *mp;
98 	cap_rights_t rights;
99 	int f, n, i;
100 	int d_first;
101 	int dfd;
102 	time_t ct;
103 
104 	w = &wd;
105 	(void) setlocale(LC_TIME, "");
106 	d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
107 
108 	while ((ch = getopt(argc, argv, "a")) != -1) {
109 		switch ((char)ch) {
110 		case 'a':
111 			aflg = 1;
112 			break;
113 		case '?':
114 		default:
115 			usage();
116 		}
117 	}
118 	argc -= optind;
119 	argv += optind;
120 
121 	if (argc != 0)
122 		usage();
123 
124 	if (chdir(_PATH_RWHODIR) < 0)
125 		err(1, "chdir(%s)", _PATH_RWHODIR);
126 	if ((dirp = opendir(".")) == NULL)
127 		err(1, "opendir(%s)", _PATH_RWHODIR);
128 	dfd = dirfd(dirp);
129 	mp = myutmp;
130 	cap_rights_init(&rights, CAP_READ, CAP_LOOKUP);
131 	if (cap_rights_limit(dfd, &rights) < 0 && errno != ENOSYS)
132 		err(1, "cap_rights_limit failed: %s", _PATH_RWHODIR);
133 	/*
134 	 * Cache files required for time(3) and localtime(3) before entering
135 	 * capability mode.
136 	 */
137 	(void) time(&ct);
138 	(void) localtime(&ct);
139 	if (cap_enter() < 0 && errno != ENOSYS)
140 		err(1, "cap_enter");
141 	(void) time(&now);
142 	cap_rights_init(&rights, CAP_READ);
143 	while ((dp = readdir(dirp)) != NULL) {
144 		if (dp->d_ino == 0 || strncmp(dp->d_name, "whod.", 5) != 0)
145 			continue;
146 		f = openat(dfd, dp->d_name, O_RDONLY);
147 		if (f < 0)
148 			continue;
149 		if (cap_rights_limit(f, &rights) < 0 && errno != ENOSYS)
150 			err(1, "cap_rights_limit failed: %s", dp->d_name);
151 		cc = read(f, (char *)&wd, sizeof(struct whod));
152 		if (cc < WHDRSIZE) {
153 			(void) close(f);
154 			continue;
155 		}
156 		if (down(w, now) != 0) {
157 			(void) close(f);
158 			continue;
159 		}
160 		cc -= WHDRSIZE;
161 		we = w->wd_we;
162 		for (n = cc / sizeof(struct whoent); n > 0; n--) {
163 			if (aflg == 0 && we->we_idle >= 60 * 60) {
164 				we++;
165 				continue;
166 			}
167 			if (nusers >= NUSERS)
168 				errx(1, "too many users");
169 			mp->myutmp = we->we_utmp;
170 			mp->myidle = we->we_idle;
171 			(void) strcpy(mp->myhost, w->wd_hostname);
172 			nusers++;
173 			we++;
174 			mp++;
175 		}
176 		(void) close(f);
177 	}
178 	qsort((char *)myutmp, nusers, sizeof(struct myutmp), utmpcmp);
179 	mp = myutmp;
180 	width = 0;
181 	for (i = 0; i < nusers; i++) {
182 		/* append one for the blank and use 8 for the out_line */
183 		int j;
184 
185 		j = strlen(mp->myhost) + 1 + sizeof(mp->myutmp.out_line);
186 		if (j > width)
187 			width = j;
188 		mp++;
189 	}
190 	mp = myutmp;
191 	for (i = 0; i < nusers; i++) {
192 		char buf[BUFSIZ], cbuf[80];
193 		time_t t;
194 
195 		t = _int_to_time(mp->myutmp.out_time);
196 		strftime(cbuf, sizeof(cbuf), d_first ? "%e %b %R" : "%b %e %R",
197 		    localtime(&t));
198 		(void) sprintf(buf, "%s:%-.*s", mp->myhost,
199 		    (int)sizeof(mp->myutmp.out_line), mp->myutmp.out_line);
200 		printf("%-*.*s %-*s %s",
201 		    (int)sizeof(mp->myutmp.out_name),
202 		    (int)sizeof(mp->myutmp.out_name),
203 		    mp->myutmp.out_name, width, buf, cbuf);
204 		mp->myidle /= 60;
205 		if (mp->myidle != 0) {
206 			if (aflg != 0) {
207 				if (mp->myidle >= 100 * 60)
208 					mp->myidle = 100 * 60 - 1;
209 				if (mp->myidle >= 60)
210 					printf(" %2d", mp->myidle / 60);
211 				else
212 					printf("   ");
213 			} else {
214 				printf(" ");
215 			}
216 			printf(":%02d", mp->myidle % 60);
217 		}
218 		printf("\n");
219 		mp++;
220 	}
221 	exit(0);
222 }
223 
224 
225 static void
226 usage(void)
227 {
228 
229 	fprintf(stderr, "usage: rwho [-a]\n");
230 	exit(1);
231 }
232 
233 #define MYUTMP(a) ((const struct myutmp *)(a))
234 
235 static int
236 utmpcmp(const void *u1, const void *u2)
237 {
238 	int rc;
239 
240 	rc = strncmp(MYUTMP(u1)->myutmp.out_name, MYUTMP(u2)->myutmp.out_name,
241 	    sizeof(MYUTMP(u2)->myutmp.out_name));
242 	if (rc != 0)
243 		return (rc);
244 	rc = strcmp(MYUTMP(u1)->myhost, MYUTMP(u2)->myhost);
245 	if (rc != 0)
246 		return (rc);
247 	return (strncmp(MYUTMP(u1)->myutmp.out_line,
248 	    MYUTMP(u2)->myutmp.out_line, sizeof(MYUTMP(u2)->myutmp.out_line)));
249 }
250