1/*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Jef Poskanzer and Craig Leres of the Lawrence Berkeley Laboratory.
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. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38static const char copyright[] =
39"@(#) Copyright (c) 1989, 1993\n\
40 The Regents of the University of California. All rights reserved.\n";
41#endif
42
43#if 0
44#ifndef lint
45static char sccsid[] = "@(#)write.c 8.1 (Berkeley) 6/6/93";
46#endif
47#endif
48
49#include <sys/cdefs.h>
| 1/*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Jef Poskanzer and Craig Leres of the Lawrence Berkeley Laboratory.
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. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38static const char copyright[] =
39"@(#) Copyright (c) 1989, 1993\n\
40 The Regents of the University of California. All rights reserved.\n";
41#endif
42
43#if 0
44#ifndef lint
45static char sccsid[] = "@(#)write.c 8.1 (Berkeley) 6/6/93";
46#endif
47#endif
48
49#include <sys/cdefs.h>
|
50__FBSDID("$FreeBSD: head/usr.bin/write/write.c 92922 2002-03-22 01:42:45Z imp $");
| 50__FBSDID("$FreeBSD: head/usr.bin/write/write.c 97454 2002-05-29 13:14:51Z tjr $");
|
51
52#include <sys/param.h>
53#include <sys/signal.h>
54#include <sys/stat.h>
55#include <sys/file.h>
56#include <sys/time.h>
57#include <ctype.h>
58#include <err.h>
59#include <locale.h>
60#include <paths.h>
61#include <pwd.h>
62#include <stdio.h>
63#include <stdlib.h>
64#include <string.h>
65#include <unistd.h>
66#include <utmp.h>
67
68void done(int);
69void do_write(char *, char *, uid_t);
70static void usage(void);
71int term_chk(char *, int *, time_t *, int);
72void wr_fputs(unsigned char *s);
73void search_utmp(char *, char *, char *, uid_t);
74int utmp_chk(char *, char *);
75
76int
77main(argc, argv)
78 int argc;
79 char **argv;
80{
81 register char *cp;
82 time_t atime;
83 uid_t myuid;
84 int msgsok, myttyfd;
85 char tty[MAXPATHLEN], *mytty;
86
87 (void)setlocale(LC_CTYPE, "");
88
| 51
52#include <sys/param.h>
53#include <sys/signal.h>
54#include <sys/stat.h>
55#include <sys/file.h>
56#include <sys/time.h>
57#include <ctype.h>
58#include <err.h>
59#include <locale.h>
60#include <paths.h>
61#include <pwd.h>
62#include <stdio.h>
63#include <stdlib.h>
64#include <string.h>
65#include <unistd.h>
66#include <utmp.h>
67
68void done(int);
69void do_write(char *, char *, uid_t);
70static void usage(void);
71int term_chk(char *, int *, time_t *, int);
72void wr_fputs(unsigned char *s);
73void search_utmp(char *, char *, char *, uid_t);
74int utmp_chk(char *, char *);
75
76int
77main(argc, argv)
78 int argc;
79 char **argv;
80{
81 register char *cp;
82 time_t atime;
83 uid_t myuid;
84 int msgsok, myttyfd;
85 char tty[MAXPATHLEN], *mytty;
86
87 (void)setlocale(LC_CTYPE, "");
88
|
| 89 while (getopt(argc, argv, "") != -1)
90 usage();
91 argc -= optind;
92 argv += optind;
93
|
89 /* check that sender has write enabled */
90 if (isatty(fileno(stdin)))
91 myttyfd = fileno(stdin);
92 else if (isatty(fileno(stdout)))
93 myttyfd = fileno(stdout);
94 else if (isatty(fileno(stderr)))
95 myttyfd = fileno(stderr);
96 else
97 errx(1, "can't find your tty");
98 if (!(mytty = ttyname(myttyfd)))
99 errx(1, "can't find your tty's name");
100 if ((cp = rindex(mytty, '/')))
101 mytty = cp + 1;
102 if (term_chk(mytty, &msgsok, &atime, 1))
103 exit(1);
104 if (!msgsok)
105 errx(1, "you have write permission turned off");
106
107 myuid = getuid();
108
109 /* check args */
110 switch (argc) {
| 94 /* check that sender has write enabled */
95 if (isatty(fileno(stdin)))
96 myttyfd = fileno(stdin);
97 else if (isatty(fileno(stdout)))
98 myttyfd = fileno(stdout);
99 else if (isatty(fileno(stderr)))
100 myttyfd = fileno(stderr);
101 else
102 errx(1, "can't find your tty");
103 if (!(mytty = ttyname(myttyfd)))
104 errx(1, "can't find your tty's name");
105 if ((cp = rindex(mytty, '/')))
106 mytty = cp + 1;
107 if (term_chk(mytty, &msgsok, &atime, 1))
108 exit(1);
109 if (!msgsok)
110 errx(1, "you have write permission turned off");
111
112 myuid = getuid();
113
114 /* check args */
115 switch (argc) {
|
111 case 2:
112 search_utmp(argv[1], tty, mytty, myuid);
| 116 case 1:
117 search_utmp(argv[0], tty, mytty, myuid);
|
113 do_write(tty, mytty, myuid);
114 break;
| 118 do_write(tty, mytty, myuid);
119 break;
|
115 case 3:
116 if (!strncmp(argv[2], _PATH_DEV, strlen(_PATH_DEV)))
117 argv[2] += strlen(_PATH_DEV);
118 if (utmp_chk(argv[1], argv[2]))
119 errx(1, "%s is not logged in on %s", argv[1], argv[2]);
120 if (term_chk(argv[2], &msgsok, &atime, 1))
| 120 case 2:
121 if (!strncmp(argv[1], _PATH_DEV, strlen(_PATH_DEV)))
122 argv[1] += strlen(_PATH_DEV);
123 if (utmp_chk(argv[0], argv[1]))
124 errx(1, "%s is not logged in on %s", argv[0], argv[1]);
125 if (term_chk(argv[1], &msgsok, &atime, 1))
|
121 exit(1);
122 if (myuid && !msgsok)
| 126 exit(1);
127 if (myuid && !msgsok)
|
123 errx(1, "%s has messages disabled on %s", argv[1], argv[2]);
124 do_write(argv[2], mytty, myuid);
| 128 errx(1, "%s has messages disabled on %s", argv[0], argv[1]);
129 do_write(argv[1], mytty, myuid);
|
125 break;
126 default:
127 usage();
128 }
129 done(0);
130 return (0);
131}
132
133static void
134usage()
135{
136 (void)fprintf(stderr, "usage: write user [tty]\n");
137 exit(1);
138}
139
140/*
141 * utmp_chk - checks that the given user is actually logged in on
142 * the given tty
143 */
144int
145utmp_chk(user, tty)
146 char *user, *tty;
147{
148 struct utmp u;
149 int ufd;
150
151 if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0)
152 return(0); /* ignore error, shouldn't happen anyway */
153
154 while (read(ufd, (char *) &u, sizeof(u)) == sizeof(u))
155 if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0 &&
156 strncmp(tty, u.ut_line, sizeof(u.ut_line)) == 0) {
157 (void)close(ufd);
158 return(0);
159 }
160
161 (void)close(ufd);
162 return(1);
163}
164
165/*
166 * search_utmp - search utmp for the "best" terminal to write to
167 *
168 * Ignores terminals with messages disabled, and of the rest, returns
169 * the one with the most recent access time. Returns as value the number
170 * of the user's terminals with messages enabled, or -1 if the user is
171 * not logged in at all.
172 *
173 * Special case for writing to yourself - ignore the terminal you're
174 * writing from, unless that's the only terminal with messages enabled.
175 */
176void
177search_utmp(user, tty, mytty, myuid)
178 char *user, *tty, *mytty;
179 uid_t myuid;
180{
181 struct utmp u;
182 time_t bestatime, atime;
183 int ufd, nloggedttys, nttys, msgsok, user_is_me;
184 char atty[UT_LINESIZE + 1];
185
186 if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0)
187 err(1, "utmp");
188
189 nloggedttys = nttys = 0;
190 bestatime = 0;
191 user_is_me = 0;
192 while (read(ufd, (char *) &u, sizeof(u)) == sizeof(u))
193 if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0) {
194 ++nloggedttys;
195 (void)strncpy(atty, u.ut_line, UT_LINESIZE);
196 atty[UT_LINESIZE] = '\0';
197 if (term_chk(atty, &msgsok, &atime, 0))
198 continue; /* bad term? skip */
199 if (myuid && !msgsok)
200 continue; /* skip ttys with msgs off */
201 if (strcmp(atty, mytty) == 0) {
202 user_is_me = 1;
203 continue; /* don't write to yourself */
204 }
205 ++nttys;
206 if (atime > bestatime) {
207 bestatime = atime;
208 (void)strcpy(tty, atty);
209 }
210 }
211
212 (void)close(ufd);
213 if (nloggedttys == 0)
214 errx(1, "%s is not logged in", user);
215 if (nttys == 0) {
216 if (user_is_me) { /* ok, so write to yourself! */
217 (void)strcpy(tty, mytty);
218 return;
219 }
220 errx(1, "%s has messages disabled", user);
221 } else if (nttys > 1) {
222 warnx("%s is logged in more than once; writing to %s", user, tty);
223 }
224}
225
226/*
227 * term_chk - check that a terminal exists, and get the message bit
228 * and the access time
229 */
230int
231term_chk(tty, msgsokP, atimeP, showerror)
232 char *tty;
233 int *msgsokP, showerror;
234 time_t *atimeP;
235{
236 struct stat s;
237 char path[MAXPATHLEN];
238
239 (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty);
240 if (stat(path, &s) < 0) {
241 if (showerror)
242 warn("%s", path);
243 return(1);
244 }
245 *msgsokP = (s.st_mode & (S_IWRITE >> 3)) != 0; /* group write bit */
246 *atimeP = s.st_atime;
247 return(0);
248}
249
250/*
251 * do_write - actually make the connection
252 */
253void
254do_write(tty, mytty, myuid)
255 char *tty, *mytty;
256 uid_t myuid;
257{
258 const char *login;
259 char *nows;
260 struct passwd *pwd;
261 time_t now;
262 char path[MAXPATHLEN], host[MAXHOSTNAMELEN], line[512];
263
264 /* Determine our login name before the we reopen() stdout */
265 if ((login = getlogin()) == NULL) {
266 if ((pwd = getpwuid(myuid)))
267 login = pwd->pw_name;
268 else
269 login = "???";
270 }
271
272 (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty);
273 if ((freopen(path, "w", stdout)) == NULL)
274 err(1, "%s", path);
275
276 (void)signal(SIGINT, done);
277 (void)signal(SIGHUP, done);
278
279 /* print greeting */
280 if (gethostname(host, sizeof(host)) < 0)
281 (void)strcpy(host, "???");
282 now = time((time_t *)NULL);
283 nows = ctime(&now);
284 nows[16] = '\0';
285 (void)printf("\r\n\007\007\007Message from %s@%s on %s at %s ...\r\n",
286 login, host, mytty, nows + 11);
287
288 while (fgets(line, sizeof(line), stdin) != NULL)
289 wr_fputs(line);
290}
291
292/*
293 * done - cleanup and exit
294 */
295void
296done(n)
297 int n __unused;
298{
299 (void)printf("EOF\r\n");
300 exit(0);
301}
302
303/*
304 * wr_fputs - like fputs(), but makes control characters visible and
305 * turns \n into \r\n
306 */
307void
308wr_fputs(s)
309 unsigned char *s;
310{
311
312#define PUTC(c) if (putchar(c) == EOF) err(1, NULL);
313
314 for (; *s != '\0'; ++s) {
315 if (*s == '\n') {
316 PUTC('\r');
317 } else if (((*s & 0x80) && *s < 0xA0) ||
318 /* disable upper controls */
319 (!isprint(*s) && !isspace(*s) &&
320 *s != '\a' && *s != '\b')
321 ) {
322 if (*s & 0x80) {
323 *s &= ~0x80;
324 PUTC('M');
325 PUTC('-');
326 }
327 if (iscntrl(*s)) {
328 *s ^= 0x40;
329 PUTC('^');
330 }
331 }
332 PUTC(*s);
333 }
334 return;
335#undef PUTC
336}
| 130 break;
131 default:
132 usage();
133 }
134 done(0);
135 return (0);
136}
137
138static void
139usage()
140{
141 (void)fprintf(stderr, "usage: write user [tty]\n");
142 exit(1);
143}
144
145/*
146 * utmp_chk - checks that the given user is actually logged in on
147 * the given tty
148 */
149int
150utmp_chk(user, tty)
151 char *user, *tty;
152{
153 struct utmp u;
154 int ufd;
155
156 if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0)
157 return(0); /* ignore error, shouldn't happen anyway */
158
159 while (read(ufd, (char *) &u, sizeof(u)) == sizeof(u))
160 if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0 &&
161 strncmp(tty, u.ut_line, sizeof(u.ut_line)) == 0) {
162 (void)close(ufd);
163 return(0);
164 }
165
166 (void)close(ufd);
167 return(1);
168}
169
170/*
171 * search_utmp - search utmp for the "best" terminal to write to
172 *
173 * Ignores terminals with messages disabled, and of the rest, returns
174 * the one with the most recent access time. Returns as value the number
175 * of the user's terminals with messages enabled, or -1 if the user is
176 * not logged in at all.
177 *
178 * Special case for writing to yourself - ignore the terminal you're
179 * writing from, unless that's the only terminal with messages enabled.
180 */
181void
182search_utmp(user, tty, mytty, myuid)
183 char *user, *tty, *mytty;
184 uid_t myuid;
185{
186 struct utmp u;
187 time_t bestatime, atime;
188 int ufd, nloggedttys, nttys, msgsok, user_is_me;
189 char atty[UT_LINESIZE + 1];
190
191 if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0)
192 err(1, "utmp");
193
194 nloggedttys = nttys = 0;
195 bestatime = 0;
196 user_is_me = 0;
197 while (read(ufd, (char *) &u, sizeof(u)) == sizeof(u))
198 if (strncmp(user, u.ut_name, sizeof(u.ut_name)) == 0) {
199 ++nloggedttys;
200 (void)strncpy(atty, u.ut_line, UT_LINESIZE);
201 atty[UT_LINESIZE] = '\0';
202 if (term_chk(atty, &msgsok, &atime, 0))
203 continue; /* bad term? skip */
204 if (myuid && !msgsok)
205 continue; /* skip ttys with msgs off */
206 if (strcmp(atty, mytty) == 0) {
207 user_is_me = 1;
208 continue; /* don't write to yourself */
209 }
210 ++nttys;
211 if (atime > bestatime) {
212 bestatime = atime;
213 (void)strcpy(tty, atty);
214 }
215 }
216
217 (void)close(ufd);
218 if (nloggedttys == 0)
219 errx(1, "%s is not logged in", user);
220 if (nttys == 0) {
221 if (user_is_me) { /* ok, so write to yourself! */
222 (void)strcpy(tty, mytty);
223 return;
224 }
225 errx(1, "%s has messages disabled", user);
226 } else if (nttys > 1) {
227 warnx("%s is logged in more than once; writing to %s", user, tty);
228 }
229}
230
231/*
232 * term_chk - check that a terminal exists, and get the message bit
233 * and the access time
234 */
235int
236term_chk(tty, msgsokP, atimeP, showerror)
237 char *tty;
238 int *msgsokP, showerror;
239 time_t *atimeP;
240{
241 struct stat s;
242 char path[MAXPATHLEN];
243
244 (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty);
245 if (stat(path, &s) < 0) {
246 if (showerror)
247 warn("%s", path);
248 return(1);
249 }
250 *msgsokP = (s.st_mode & (S_IWRITE >> 3)) != 0; /* group write bit */
251 *atimeP = s.st_atime;
252 return(0);
253}
254
255/*
256 * do_write - actually make the connection
257 */
258void
259do_write(tty, mytty, myuid)
260 char *tty, *mytty;
261 uid_t myuid;
262{
263 const char *login;
264 char *nows;
265 struct passwd *pwd;
266 time_t now;
267 char path[MAXPATHLEN], host[MAXHOSTNAMELEN], line[512];
268
269 /* Determine our login name before the we reopen() stdout */
270 if ((login = getlogin()) == NULL) {
271 if ((pwd = getpwuid(myuid)))
272 login = pwd->pw_name;
273 else
274 login = "???";
275 }
276
277 (void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty);
278 if ((freopen(path, "w", stdout)) == NULL)
279 err(1, "%s", path);
280
281 (void)signal(SIGINT, done);
282 (void)signal(SIGHUP, done);
283
284 /* print greeting */
285 if (gethostname(host, sizeof(host)) < 0)
286 (void)strcpy(host, "???");
287 now = time((time_t *)NULL);
288 nows = ctime(&now);
289 nows[16] = '\0';
290 (void)printf("\r\n\007\007\007Message from %s@%s on %s at %s ...\r\n",
291 login, host, mytty, nows + 11);
292
293 while (fgets(line, sizeof(line), stdin) != NULL)
294 wr_fputs(line);
295}
296
297/*
298 * done - cleanup and exit
299 */
300void
301done(n)
302 int n __unused;
303{
304 (void)printf("EOF\r\n");
305 exit(0);
306}
307
308/*
309 * wr_fputs - like fputs(), but makes control characters visible and
310 * turns \n into \r\n
311 */
312void
313wr_fputs(s)
314 unsigned char *s;
315{
316
317#define PUTC(c) if (putchar(c) == EOF) err(1, NULL);
318
319 for (; *s != '\0'; ++s) {
320 if (*s == '\n') {
321 PUTC('\r');
322 } else if (((*s & 0x80) && *s < 0xA0) ||
323 /* disable upper controls */
324 (!isprint(*s) && !isspace(*s) &&
325 *s != '\a' && *s != '\b')
326 ) {
327 if (*s & 0x80) {
328 *s &= ~0x80;
329 PUTC('M');
330 PUTC('-');
331 }
332 if (iscntrl(*s)) {
333 *s ^= 0x40;
334 PUTC('^');
335 }
336 }
337 PUTC(*s);
338 }
339 return;
340#undef PUTC
341}
|