File: | src/usr.bin/wall/wall.c |
Warning: | line 193, column 21 The left operand of '==' is a garbage value |
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1 | /* $OpenBSD: wall.c,v 1.37 2023/03/08 04:43:12 guenther Exp $ */ | |||
2 | /* $NetBSD: wall.c,v 1.6 1994/11/17 07:17:58 jtc Exp $ */ | |||
3 | ||||
4 | /* | |||
5 | * Copyright (c) 1988, 1990, 1993 | |||
6 | * The Regents of the University of California. 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 | /* | |||
34 | * This program is not related to David Wall, whose Stanford Ph.D. thesis | |||
35 | * is entitled "Mechanisms for Broadcast and Selective Broadcast". | |||
36 | */ | |||
37 | ||||
38 | #include <sys/queue.h> | |||
39 | #include <sys/stat.h> | |||
40 | #include <sys/time.h> | |||
41 | #include <sys/uio.h> | |||
42 | ||||
43 | #include <ctype.h> | |||
44 | #include <err.h> | |||
45 | #include <grp.h> | |||
46 | #include <limits.h> | |||
47 | #include <paths.h> | |||
48 | #include <pwd.h> | |||
49 | #include <stdio.h> | |||
50 | #include <stdlib.h> | |||
51 | #include <string.h> | |||
52 | #include <unistd.h> | |||
53 | #include <utmp.h> | |||
54 | ||||
55 | struct wallgroup { | |||
56 | gid_t gid; | |||
57 | char *name; | |||
58 | char **mem; | |||
59 | struct wallgroup *next; | |||
60 | } *grouplist; | |||
61 | ||||
62 | struct utmptty { | |||
63 | char *tty; | |||
64 | SLIST_ENTRY(utmptty)struct { struct utmptty *sle_next; } next; | |||
65 | }; | |||
66 | ||||
67 | void makemsg(char *); | |||
68 | void addgroup(struct group *, char *); | |||
69 | char *ttymsg(struct iovec *, int, char *, int); | |||
70 | __dead__attribute__((__noreturn__)) void usage(void); | |||
71 | static int isu8cont(unsigned char); | |||
72 | ||||
73 | int nobanner; | |||
74 | int mbufsize; | |||
75 | char *mbuf; | |||
76 | ||||
77 | int | |||
78 | main(int argc, char **argv) | |||
79 | { | |||
80 | FILE *fp; | |||
81 | int ch, ingroup; | |||
82 | struct iovec iov; | |||
83 | struct utmp utmp; | |||
84 | char *p, **mem; | |||
85 | char line[sizeof(utmp.ut_line) + 1]; | |||
86 | char username[sizeof(utmp.ut_name) + 1]; | |||
87 | struct passwd *pw; | |||
88 | struct group *grp; | |||
89 | struct wallgroup *g; | |||
90 | struct utmptty *un; | |||
91 | SLIST_HEAD(,utmptty)struct { struct utmptty *slh_first; } utmphead; | |||
92 | SLIST_INIT(&utmphead){ ((&utmphead)->slh_first) = ((void *)0); }; | |||
93 | ||||
94 | while ((ch = getopt(argc, argv, "ng:")) != -1) | |||
| ||||
95 | switch (ch) { | |||
96 | case 'n': | |||
97 | /* undoc option for shutdown: suppress banner */ | |||
98 | pw = getpwnam("nobody"); | |||
99 | if (geteuid() == 0 || (pw && getuid() == pw->pw_uid)) | |||
100 | nobanner = 1; | |||
101 | break; | |||
102 | case 'g': | |||
103 | if ((grp = getgrnam(optarg)) == NULL((void *)0)) | |||
104 | errx(1, "unknown group `%s'", optarg); | |||
105 | addgroup(grp, optarg); | |||
106 | break; | |||
107 | default: | |||
108 | usage(); | |||
109 | } | |||
110 | argc -= optind; | |||
111 | argv += optind; | |||
112 | if (argc > 1) | |||
113 | usage(); | |||
114 | ||||
115 | makemsg(*argv); | |||
116 | ||||
117 | if (unveil(_PATH_UTMP"/var/run/utmp", "r") == -1) | |||
118 | err(1, "unveil %s", _PATH_UTMP"/var/run/utmp"); | |||
119 | if (unveil(_PATH_DEV"/dev/", "w") == -1) | |||
120 | err(1, "unveil %s", _PATH_DEV"/dev/"); | |||
121 | if (unveil(_PATH_DEVDB"/var/run/dev.db", "r") == -1) | |||
122 | err(1, "unveil %s", _PATH_DEVDB"/var/run/dev.db"); | |||
123 | if (pledge("stdio rpath wpath getpw proc", NULL((void *)0)) == -1) | |||
124 | err(1, "pledge"); | |||
125 | ||||
126 | if (!(fp = fopen(_PATH_UTMP"/var/run/utmp", "r"))) | |||
127 | err(1, "cannot read %s", _PATH_UTMP"/var/run/utmp"); | |||
128 | iov.iov_base = mbuf; | |||
129 | iov.iov_len = mbufsize; | |||
130 | ||||
131 | while (fread(&utmp, sizeof(utmp), 1, fp) == 1) { | |||
132 | if (!utmp.ut_name[0]) | |||
133 | continue; | |||
134 | if (grouplist) { | |||
135 | ingroup = 0; | |||
136 | strncpy(username, utmp.ut_name, sizeof(utmp.ut_name)); | |||
137 | username[sizeof(utmp.ut_name)] = '\0'; | |||
138 | pw = getpwnam(username); | |||
139 | if (!pw) | |||
140 | continue; | |||
141 | for (g = grouplist; g && ingroup == 0; g = g->next) { | |||
142 | if (g->gid == pw->pw_gid) | |||
143 | ingroup = 1; | |||
144 | for (mem = g->mem; *mem && ingroup == 0; mem++) | |||
145 | if (strcmp(username, *mem) == 0) | |||
146 | ingroup = 1; | |||
147 | } | |||
148 | if (ingroup == 0) | |||
149 | continue; | |||
150 | } | |||
151 | strncpy(line, utmp.ut_line, sizeof(utmp.ut_line)); | |||
152 | line[sizeof(utmp.ut_line)] = '\0'; | |||
153 | un = malloc(sizeof(struct utmptty)); | |||
154 | if (un == NULL((void *)0)) | |||
155 | err(1, "malloc"); | |||
156 | un->tty = strndup(line, sizeof(utmp.ut_line)); | |||
157 | if (un->tty == NULL((void *)0)) | |||
158 | err(1, "strndup"); | |||
159 | SLIST_INSERT_HEAD(&utmphead, un, next)do { (un)->next.sle_next = (&utmphead)->slh_first; ( &utmphead)->slh_first = (un); } while (0); | |||
160 | } | |||
161 | fclose(fp); | |||
162 | ||||
163 | if (pledge("stdio rpath wpath proc", NULL((void *)0)) == -1) | |||
164 | err(1, "pledge"); | |||
165 | ||||
166 | SLIST_FOREACH(un, &utmphead, next)for((un) = ((&utmphead)->slh_first); (un) != ((void *) 0); (un) = ((un)->next.sle_next)) { | |||
167 | if ((p = ttymsg(&iov, 1, un->tty, 60*5)) != NULL((void *)0)) | |||
168 | warnx("%s", p); | |||
169 | } | |||
170 | ||||
171 | exit(0); | |||
172 | } | |||
173 | ||||
174 | void | |||
175 | makemsg(char *fname) | |||
176 | { | |||
177 | int cnt; | |||
178 | struct tm *lt; | |||
179 | struct passwd *pw; | |||
180 | struct stat sbuf; | |||
181 | time_t now; | |||
182 | FILE *fp; | |||
183 | int fd; | |||
184 | char *p, *whom, hostname[HOST_NAME_MAX255+1], lbuf[100], tmpname[PATH_MAX1024]; | |||
185 | char *ttynam; | |||
186 | unsigned char ch; | |||
187 | ||||
188 | snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXXXXXX", _PATH_TMP"/tmp/"); | |||
189 | if ((fd = mkstemp(tmpname)) >= 0) { | |||
190 | (void)unlink(tmpname); | |||
191 | fp = fdopen(fd, "r+"); | |||
192 | } | |||
193 | if (fd == -1 || fp == NULL((void *)0)) | |||
| ||||
194 | err(1, "can't open temporary file"); | |||
195 | ||||
196 | if (!nobanner) { | |||
197 | if (!(whom = getlogin())) | |||
198 | whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; | |||
199 | (void)gethostname(hostname, sizeof(hostname)); | |||
200 | (void)time(&now); | |||
201 | lt = localtime(&now); | |||
202 | if ((ttynam = ttyname(STDERR_FILENO2)) == NULL((void *)0)) | |||
203 | ttynam = "(not a tty)"; | |||
204 | ||||
205 | /* | |||
206 | * all this stuff is to blank out a square for the message; | |||
207 | * we wrap message lines at column 79, not 80, because some | |||
208 | * terminals wrap after 79, some do not, and we can't tell. | |||
209 | * Which means that we may leave a non-blank character | |||
210 | * in column 80, but that can't be helped. | |||
211 | */ | |||
212 | (void)fprintf(fp, "\r%79s\r\n", " "); | |||
213 | (void)snprintf(lbuf, sizeof lbuf, | |||
214 | "Broadcast Message from %s@%s", whom, hostname); | |||
215 | (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); | |||
216 | (void)snprintf(lbuf, sizeof lbuf, | |||
217 | " (%s) at %d:%02d ...", ttynam, | |||
218 | lt->tm_hour, lt->tm_min); | |||
219 | (void)fprintf(fp, "%-79.79s\r\n", lbuf); | |||
220 | } | |||
221 | (void)fprintf(fp, "%79s\r\n", " "); | |||
222 | ||||
223 | if (fname) { | |||
224 | gid_t egid = getegid(); | |||
225 | ||||
226 | setegid(getgid()); | |||
227 | if (freopen(fname, "r", stdin(&__sF[0])) == NULL((void *)0)) | |||
228 | err(1, "can't read %s", fname); | |||
229 | setegid(egid); | |||
230 | } | |||
231 | cnt = 0; | |||
232 | while (fgets(lbuf, sizeof(lbuf), stdin(&__sF[0]))) | |||
233 | for (p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { | |||
234 | if (cnt == 79 || ch == '\n') { | |||
235 | for (; cnt < 79; ++cnt) | |||
236 | putc(' ', fp)(!__isthreaded ? __sputc(' ', fp) : (putc)(' ', fp)); | |||
237 | putc('\r', fp)(!__isthreaded ? __sputc('\r', fp) : (putc)('\r', fp)); | |||
238 | putc('\n', fp)(!__isthreaded ? __sputc('\n', fp) : (putc)('\n', fp)); | |||
239 | cnt = -1; | |||
240 | if (ch != '\n') | |||
241 | p--; | |||
242 | } else if (!isu8cont(ch)) | |||
243 | putc(isprint(ch) || isspace(ch) || ch == '\a' ?(!__isthreaded ? __sputc(isprint(ch) || isspace(ch) || ch == '\a' ? ch : '?', fp) : (putc)(isprint(ch) || isspace(ch) || ch == '\a' ? ch : '?', fp)) | |||
244 | ch : '?', fp)(!__isthreaded ? __sputc(isprint(ch) || isspace(ch) || ch == '\a' ? ch : '?', fp) : (putc)(isprint(ch) || isspace(ch) || ch == '\a' ? ch : '?', fp)); | |||
245 | } | |||
246 | (void)fprintf(fp, "%79s\r\n", " "); | |||
247 | rewind(fp); | |||
248 | ||||
249 | if (fstat(fd, &sbuf)) | |||
250 | err(1, "can't stat temporary file"); | |||
251 | mbufsize = sbuf.st_size; | |||
252 | mbuf = malloc((u_int)mbufsize); | |||
253 | if (mbuf == NULL((void *)0)) | |||
254 | err(1, NULL((void *)0)); | |||
255 | if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) | |||
256 | err(1, "can't read temporary file"); | |||
257 | (void)close(fd); | |||
258 | } | |||
259 | ||||
260 | void | |||
261 | addgroup(struct group *grp, char *name) | |||
262 | { | |||
263 | int i; | |||
264 | struct wallgroup *g; | |||
265 | ||||
266 | for (i = 0; grp->gr_mem[i]; i++) | |||
267 | ; | |||
268 | ||||
269 | g = malloc(sizeof *g); | |||
270 | if (g == NULL((void *)0)) | |||
271 | err(1, NULL((void *)0)); | |||
272 | g->gid = grp->gr_gid; | |||
273 | g->name = name; | |||
274 | g->mem = calloc(i + 1, sizeof(char *)); | |||
275 | if (g->mem == NULL((void *)0)) | |||
276 | err(1, NULL((void *)0)); | |||
277 | for (i = 0; grp->gr_mem[i] != NULL((void *)0); i++) { | |||
278 | g->mem[i] = strdup(grp->gr_mem[i]); | |||
279 | if (g->mem[i] == NULL((void *)0)) | |||
280 | err(1, NULL((void *)0)); | |||
281 | } | |||
282 | g->mem[i] = NULL((void *)0); | |||
283 | g->next = grouplist; | |||
284 | grouplist = g; | |||
285 | } | |||
286 | ||||
287 | void | |||
288 | usage(void) | |||
289 | { | |||
290 | extern char *__progname; | |||
291 | ||||
292 | (void)fprintf(stderr(&__sF[2]), "usage: %s [-g group] [file]\n", __progname); | |||
293 | exit(1); | |||
294 | } | |||
295 | ||||
296 | static int | |||
297 | isu8cont(unsigned char c) | |||
298 | { | |||
299 | return (c & (0x80 | 0x40)) == 0x80; | |||
300 | } |