xref: /freebsd/usr.bin/rwho/rwho.c (revision d2ba5111c125104b09aa1acd1bfe8af2a24c79cc)
1 /*-
2  * Copyright (c) 1983, 1993 The Regents of the University of California.
3  * Copyright (c) 2013 Mariusz Zaborski <oshogbo@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #ifndef lint
32 static const char copyright[] =
33 "@(#) Copyright (c) 1983, 1993\n\
34 	The Regents of the University of California.  All rights reserved.\n";
35 #endif /* not lint */
36 
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)rwho.c	8.1 (Berkeley) 6/6/93";
40 #endif
41 #endif /* not lint */
42 
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
45 
46 #include <sys/capsicum.h>
47 #include <sys/param.h>
48 #include <sys/file.h>
49 
50 #include <protocols/rwhod.h>
51 
52 #include <dirent.h>
53 #include <err.h>
54 #include <errno.h>
55 #include <langinfo.h>
56 #include <locale.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #include <time.h>
61 #include <timeconv.h>
62 #include <unistd.h>
63 
64 #define	NUSERS		1000
65 #define	WHDRSIZE	(ssize_t)(sizeof(wd) - sizeof(wd.wd_we))
66 /*
67  * this macro should be shared with ruptime.
68  */
69 #define	down(w,now)	((now) - (w)->wd_recvtime > 11 * 60)
70 
71 static DIR	*dirp;
72 static struct	whod wd;
73 static int	nusers;
74 static struct	myutmp {
75 	char    myhost[sizeof(wd.wd_hostname)];
76 	int	myidle;
77 	struct	outmp myutmp;
78 } myutmp[NUSERS];
79 
80 static time_t	now;
81 static int	aflg;
82 
83 static void usage(void);
84 static int utmpcmp(const void *, const void *);
85 
86 int
87 main(int argc, char *argv[])
88 {
89 	int ch;
90 	struct dirent *dp;
91 	int width;
92 	ssize_t cc;
93 	struct whod *w;
94 	struct whoent *we;
95 	struct myutmp *mp;
96 	cap_rights_t rights;
97 	int f, n, i;
98 	int d_first;
99 	int dfd;
100 	time_t ct;
101 
102 	w = &wd;
103 	(void) setlocale(LC_TIME, "");
104 	d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
105 
106 	while ((ch = getopt(argc, argv, "a")) != -1) {
107 		switch ((char)ch) {
108 		case 'a':
109 			aflg = 1;
110 			break;
111 		case '?':
112 		default:
113 			usage();
114 		}
115 	}
116 	argc -= optind;
117 	argv += optind;
118 
119 	if (argc != 0)
120 		usage();
121 
122 	if (chdir(_PATH_RWHODIR) < 0)
123 		err(1, "chdir(%s)", _PATH_RWHODIR);
124 	if ((dirp = opendir(".")) == NULL)
125 		err(1, "opendir(%s)", _PATH_RWHODIR);
126 	dfd = dirfd(dirp);
127 	mp = myutmp;
128 	cap_rights_init(&rights, CAP_READ, CAP_LOOKUP);
129 	if (cap_rights_limit(dfd, &rights) < 0 && errno != ENOSYS)
130 		err(1, "cap_rights_limit failed: %s", _PATH_RWHODIR);
131 	/*
132 	 * Cache files required for time(3) and localtime(3) before entering
133 	 * capability mode.
134 	 */
135 	(void) time(&ct);
136 	(void) localtime(&ct);
137 	if (cap_enter() < 0 && errno != ENOSYS)
138 		err(1, "cap_enter");
139 	(void) time(&now);
140 	cap_rights_init(&rights, CAP_READ);
141 	while ((dp = readdir(dirp)) != NULL) {
142 		if (dp->d_ino == 0 || strncmp(dp->d_name, "whod.", 5) != 0)
143 			continue;
144 		f = openat(dfd, dp->d_name, O_RDONLY);
145 		if (f < 0)
146 			continue;
147 		if (cap_rights_limit(f, &rights) < 0 && errno != ENOSYS)
148 			err(1, "cap_rights_limit failed: %s", dp->d_name);
149 		cc = read(f, (char *)&wd, sizeof(struct whod));
150 		if (cc < WHDRSIZE) {
151 			(void) close(f);
152 			continue;
153 		}
154 		if (down(w, now) != 0) {
155 			(void) close(f);
156 			continue;
157 		}
158 		cc -= WHDRSIZE;
159 		we = w->wd_we;
160 		for (n = cc / sizeof(struct whoent); n > 0; n--) {
161 			if (aflg == 0 && we->we_idle >= 60 * 60) {
162 				we++;
163 				continue;
164 			}
165 			if (nusers >= NUSERS)
166 				errx(1, "too many users");
167 			mp->myutmp = we->we_utmp;
168 			mp->myidle = we->we_idle;
169 			(void) strcpy(mp->myhost, w->wd_hostname);
170 			nusers++;
171 			we++;
172 			mp++;
173 		}
174 		(void) close(f);
175 	}
176 	qsort((char *)myutmp, nusers, sizeof(struct myutmp), utmpcmp);
177 	mp = myutmp;
178 	width = 0;
179 	for (i = 0; i < nusers; i++) {
180 		/* append one for the blank and use 8 for the out_line */
181 		int j;
182 
183 		j = strlen(mp->myhost) + 1 + sizeof(mp->myutmp.out_line);
184 		if (j > width)
185 			width = j;
186 		mp++;
187 	}
188 	mp = myutmp;
189 	for (i = 0; i < nusers; i++) {
190 		char buf[BUFSIZ], cbuf[80];
191 		time_t t;
192 
193 		t = _int_to_time(mp->myutmp.out_time);
194 		strftime(cbuf, sizeof(cbuf), d_first ? "%e %b %R" : "%b %e %R",
195 		    localtime(&t));
196 		(void) sprintf(buf, "%s:%-.*s", mp->myhost,
197 		    (int)sizeof(mp->myutmp.out_line), mp->myutmp.out_line);
198 		printf("%-*.*s %-*s %s",
199 		    (int)sizeof(mp->myutmp.out_name),
200 		    (int)sizeof(mp->myutmp.out_name),
201 		    mp->myutmp.out_name, width, buf, cbuf);
202 		mp->myidle /= 60;
203 		if (mp->myidle != 0) {
204 			if (aflg != 0) {
205 				if (mp->myidle >= 100 * 60)
206 					mp->myidle = 100 * 60 - 1;
207 				if (mp->myidle >= 60)
208 					printf(" %2d", mp->myidle / 60);
209 				else
210 					printf("   ");
211 			} else {
212 				printf(" ");
213 			}
214 			printf(":%02d", mp->myidle % 60);
215 		}
216 		printf("\n");
217 		mp++;
218 	}
219 	exit(0);
220 }
221 
222 
223 static void
224 usage(void)
225 {
226 
227 	fprintf(stderr, "usage: rwho [-a]\n");
228 	exit(1);
229 }
230 
231 #define MYUTMP(a) ((const struct myutmp *)(a))
232 
233 static int
234 utmpcmp(const void *u1, const void *u2)
235 {
236 	int rc;
237 
238 	rc = strncmp(MYUTMP(u1)->myutmp.out_name, MYUTMP(u2)->myutmp.out_name,
239 	    sizeof(MYUTMP(u2)->myutmp.out_name));
240 	if (rc != 0)
241 		return (rc);
242 	rc = strcmp(MYUTMP(u1)->myhost, MYUTMP(u2)->myhost);
243 	if (rc != 0)
244 		return (rc);
245 	return (strncmp(MYUTMP(u1)->myutmp.out_line,
246 	    MYUTMP(u2)->myutmp.out_line, sizeof(MYUTMP(u2)->myutmp.out_line)));
247 }
248