xref: /freebsd/usr.bin/rwho/rwho.c (revision af23369a6deaaeb612ab266eb88b8bb8d560c322)
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 <capsicum_helpers.h>
55 #include <dirent.h>
56 #include <err.h>
57 #include <errno.h>
58 #include <langinfo.h>
59 #include <locale.h>
60 #include <stdio.h>
61 #include <stdlib.h>
62 #include <string.h>
63 #include <time.h>
64 #include <timeconv.h>
65 #include <unistd.h>
66 
67 #define	NUSERS		1000
68 #define	WHDRSIZE	(ssize_t)(sizeof(wd) - sizeof(wd.wd_we))
69 /*
70  * this macro should be shared with ruptime.
71  */
72 #define	down(w,now)	((now) - (w)->wd_recvtime > 11 * 60)
73 
74 static DIR	*dirp;
75 static struct	whod wd;
76 static int	nusers;
77 static struct	myutmp {
78 	char    myhost[sizeof(wd.wd_hostname)];
79 	int	myidle;
80 	struct	outmp myutmp;
81 } myutmp[NUSERS];
82 
83 static time_t	now;
84 static int	aflg;
85 
86 static void usage(void);
87 static int utmpcmp(const void *, const void *);
88 
89 int
90 main(int argc, char *argv[])
91 {
92 	int ch;
93 	struct dirent *dp;
94 	int width;
95 	ssize_t cc;
96 	struct whod *w;
97 	struct whoent *we;
98 	struct myutmp *mp;
99 	cap_rights_t rights;
100 	int f, n, i;
101 	int d_first;
102 	int dfd;
103 	time_t ct;
104 
105 	w = &wd;
106 	(void) setlocale(LC_TIME, "");
107 	d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
108 
109 	while ((ch = getopt(argc, argv, "a")) != -1) {
110 		switch ((char)ch) {
111 		case 'a':
112 			aflg = 1;
113 			break;
114 		case '?':
115 		default:
116 			usage();
117 		}
118 	}
119 	argc -= optind;
120 	argv += optind;
121 
122 	if (argc != 0)
123 		usage();
124 
125 	if (chdir(_PATH_RWHODIR) < 0)
126 		err(1, "chdir(%s)", _PATH_RWHODIR);
127 	if ((dirp = opendir(".")) == NULL)
128 		err(1, "opendir(%s)", _PATH_RWHODIR);
129 	dfd = dirfd(dirp);
130 	mp = myutmp;
131 	cap_rights_init(&rights, CAP_READ, CAP_LOOKUP);
132 	if (caph_rights_limit(dfd, &rights) < 0)
133 		err(1, "cap_rights_limit failed: %s", _PATH_RWHODIR);
134 	/*
135 	 * Cache files required for time(3) and localtime(3) before entering
136 	 * capability mode.
137 	 */
138 	(void) time(&ct);
139 	(void) localtime(&ct);
140 	if (caph_enter() < 0)
141 		err(1, "cap_enter");
142 	(void) time(&now);
143 	cap_rights_init(&rights, CAP_READ);
144 	while ((dp = readdir(dirp)) != NULL) {
145 		if (dp->d_ino == 0 || strncmp(dp->d_name, "whod.", 5) != 0)
146 			continue;
147 		f = openat(dfd, dp->d_name, O_RDONLY);
148 		if (f < 0)
149 			continue;
150 		if (caph_rights_limit(f, &rights) < 0)
151 			err(1, "cap_rights_limit failed: %s", dp->d_name);
152 		cc = read(f, (char *)&wd, sizeof(struct whod));
153 		if (cc < WHDRSIZE) {
154 			(void) close(f);
155 			continue;
156 		}
157 		if (down(w, now) != 0) {
158 			(void) close(f);
159 			continue;
160 		}
161 		cc -= WHDRSIZE;
162 		we = w->wd_we;
163 		for (n = cc / sizeof(struct whoent); n > 0; n--) {
164 			if (aflg == 0 && we->we_idle >= 60 * 60) {
165 				we++;
166 				continue;
167 			}
168 			if (nusers >= NUSERS)
169 				errx(1, "too many users");
170 			mp->myutmp = we->we_utmp;
171 			mp->myidle = we->we_idle;
172 			(void) strcpy(mp->myhost, w->wd_hostname);
173 			nusers++;
174 			we++;
175 			mp++;
176 		}
177 		(void) close(f);
178 	}
179 	qsort((char *)myutmp, nusers, sizeof(struct myutmp), utmpcmp);
180 	mp = myutmp;
181 	width = 0;
182 	for (i = 0; i < nusers; i++) {
183 		/* append one for the blank and use 8 for the out_line */
184 		int j;
185 
186 		j = strlen(mp->myhost) + 1 + sizeof(mp->myutmp.out_line);
187 		if (j > width)
188 			width = j;
189 		mp++;
190 	}
191 	mp = myutmp;
192 	for (i = 0; i < nusers; i++) {
193 		char buf[BUFSIZ], cbuf[80];
194 		time_t t;
195 
196 		t = _int_to_time(mp->myutmp.out_time);
197 		strftime(cbuf, sizeof(cbuf), d_first ? "%e %b %R" : "%b %e %R",
198 		    localtime(&t));
199 		(void) sprintf(buf, "%s:%-.*s", mp->myhost,
200 		    (int)sizeof(mp->myutmp.out_line), mp->myutmp.out_line);
201 		printf("%-*.*s %-*s %s",
202 		    (int)sizeof(mp->myutmp.out_name),
203 		    (int)sizeof(mp->myutmp.out_name),
204 		    mp->myutmp.out_name, width, buf, cbuf);
205 		mp->myidle /= 60;
206 		if (mp->myidle != 0) {
207 			if (aflg != 0) {
208 				if (mp->myidle >= 100 * 60)
209 					mp->myidle = 100 * 60 - 1;
210 				if (mp->myidle >= 60)
211 					printf(" %2d", mp->myidle / 60);
212 				else
213 					printf("   ");
214 			} else {
215 				printf(" ");
216 			}
217 			printf(":%02d", mp->myidle % 60);
218 		}
219 		printf("\n");
220 		mp++;
221 	}
222 	exit(0);
223 }
224 
225 
226 static void
227 usage(void)
228 {
229 
230 	fprintf(stderr, "usage: rwho [-a]\n");
231 	exit(1);
232 }
233 
234 #define MYUTMP(a) ((const struct myutmp *)(a))
235 
236 static int
237 utmpcmp(const void *u1, const void *u2)
238 {
239 	int rc;
240 
241 	rc = strncmp(MYUTMP(u1)->myutmp.out_name, MYUTMP(u2)->myutmp.out_name,
242 	    sizeof(MYUTMP(u2)->myutmp.out_name));
243 	if (rc != 0)
244 		return (rc);
245 	rc = strcmp(MYUTMP(u1)->myhost, MYUTMP(u2)->myhost);
246 	if (rc != 0)
247 		return (rc);
248 	return (strncmp(MYUTMP(u1)->myutmp.out_line,
249 	    MYUTMP(u2)->myutmp.out_line, sizeof(MYUTMP(u2)->myutmp.out_line)));
250 }
251