Annotation of src/usr.bin/wall/wall.c, Revision 1.15
1.15 ! millert 1: /* $OpenBSD: wall.c,v 1.14 2001/02/13 09:16:04 deraadt Exp $ */
1.1 deraadt 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. 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
1.15 ! millert 38: static const char copyright[] =
1.1 deraadt 39: "@(#) Copyright (c) 1988, 1990, 1993\n\
40: The Regents of the University of California. All rights reserved.\n";
41: #endif /* not lint */
42:
43: #ifndef lint
44: #if 0
1.15 ! millert 45: static const char sccsid[] = "@(#)wall.c 8.2 (Berkeley) 11/16/93";
1.1 deraadt 46: #endif
1.15 ! millert 47: static const char rcsid[] = "$OpenBSD: wall.c,v 1.14 2001/02/13 09:16:04 deraadt Exp $";
1.1 deraadt 48: #endif /* not lint */
49:
50: /*
51: * This program is not related to David Wall, whose Stanford Ph.D. thesis
52: * is entitled "Mechanisms for Broadcast and Selective Broadcast".
53: */
54:
55: #include <sys/param.h>
56: #include <sys/stat.h>
57: #include <sys/time.h>
58: #include <sys/uio.h>
59:
60: #include <paths.h>
61: #include <pwd.h>
1.6 deraadt 62: #include <grp.h>
1.1 deraadt 63: #include <stdio.h>
64: #include <stdlib.h>
65: #include <string.h>
66: #include <unistd.h>
67: #include <utmp.h>
1.4 deraadt 68: #include <vis.h>
1.9 form 69: #include <err.h>
1.1 deraadt 70:
1.6 deraadt 71: struct wallgroup {
1.15 ! millert 72: gid_t gid;
! 73: char *name;
! 74: char **mem;
1.6 deraadt 75: struct wallgroup *next;
76: } *grouplist;
77:
1.15 ! millert 78: void makemsg(char *);
! 79: void addgroup(struct group *, char *);
! 80: char *ttymsg(struct iovec *, int, char *, int);
! 81: __dead void usage(void);
1.1 deraadt 82:
83: #define IGNOREUSER "sleeper"
84:
85: int nobanner;
86: int mbufsize;
87: char *mbuf;
88:
89: /* ARGSUSED */
90: int
1.15 ! millert 91: main(int argc, char **argv)
1.1 deraadt 92: {
1.15 ! millert 93: FILE *fp;
! 94: int ch, ingroup;
1.1 deraadt 95: struct iovec iov;
96: struct utmp utmp;
1.15 ! millert 97: char *p, **mem;
1.1 deraadt 98: char line[sizeof(utmp.ut_line) + 1];
1.15 ! millert 99: char username[sizeof(utmp.ut_name) + 1];
! 100: struct passwd *pw;
! 101: struct group *grp;
1.6 deraadt 102: struct wallgroup *g;
1.1 deraadt 103:
1.8 millert 104: while ((ch = getopt(argc, argv, "ng:")) != -1)
1.1 deraadt 105: switch (ch) {
106: case 'n':
107: /* undoc option for shutdown: suppress banner */
1.15 ! millert 108: pw = getpwnam("nobody");
! 109: if (geteuid() == 0 || (pw && getuid() == pw->pw_uid))
1.1 deraadt 110: nobanner = 1;
111: break;
1.6 deraadt 112: case 'g':
1.15 ! millert 113: grp = getgrnam(optarg);
! 114: if ((grp = getgrnam(optarg)) == NULL)
! 115: errx(1, "unknown group `%s'", optarg);
! 116: addgroup(grp, optarg);
1.6 deraadt 117: break;
1.1 deraadt 118: default:
1.15 ! millert 119: usage();
1.1 deraadt 120: }
121: argc -= optind;
122: argv += optind;
123: if (argc > 1)
1.15 ! millert 124: usage();
1.6 deraadt 125:
1.1 deraadt 126: makemsg(*argv);
127:
1.9 form 128: if (!(fp = fopen(_PATH_UTMP, "r")))
1.13 deraadt 129: errx(1, "cannot read %s.", _PATH_UTMP);
1.1 deraadt 130: iov.iov_base = mbuf;
131: iov.iov_len = mbufsize;
132: /* NOSTRICT */
1.15 ! millert 133: while (fread(&utmp, sizeof(utmp), 1, fp) == 1) {
1.1 deraadt 134: if (!utmp.ut_name[0] ||
135: !strncmp(utmp.ut_name, IGNOREUSER, sizeof(utmp.ut_name)))
136: continue;
1.6 deraadt 137: if (grouplist) {
1.15 ! millert 138: ingroup = 0;
! 139: strncpy(username, utmp.ut_name, sizeof(utmp.ut_name));
! 140: username[sizeof(utmp.ut_name)] = '\0';
1.6 deraadt 141: pw = getpwnam(username);
142: if (!pw)
143: continue;
144: for (g = grouplist; g && ingroup == 0; g = g->next) {
145: if (g->gid == pw->pw_gid)
146: ingroup = 1;
1.15 ! millert 147: for (mem = g->mem; *mem && ingroup == 0; mem++)
! 148: if (strcmp(username, *mem) == 0)
1.6 deraadt 149: ingroup = 1;
150: }
151: if (ingroup == 0)
152: continue;
153: }
1.1 deraadt 154: strncpy(line, utmp.ut_line, sizeof(utmp.ut_line));
155: line[sizeof(utmp.ut_line)] = '\0';
156: if ((p = ttymsg(&iov, 1, line, 60*5)) != NULL)
1.13 deraadt 157: warnx("%s", p);
1.1 deraadt 158: }
159: exit(0);
160: }
161:
162: void
1.15 ! millert 163: makemsg(char *fname)
1.1 deraadt 164: {
1.15 ! millert 165: int ch, cnt;
1.1 deraadt 166: struct tm *lt;
167: struct passwd *pw;
168: struct stat sbuf;
169: time_t now, time();
170: FILE *fp;
171: int fd;
1.10 deraadt 172: char *p, *whom, hostname[MAXHOSTNAMELEN], lbuf[100], tmpname[64];
1.4 deraadt 173: char tmpbuf[5];
1.11 d 174: char *ttynam;
1.1 deraadt 175:
1.10 deraadt 176: snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP);
1.15 ! millert 177: if ((fd = mkstemp(tmpname)) >= 0) {
! 178: (void)unlink(tmpname);
! 179: fp = fdopen(fd, "r+");
! 180: }
! 181: if (fd == -1 || fp == NULL)
1.13 deraadt 182: errx(1, "can't open temporary file.");
1.1 deraadt 183:
184: if (!nobanner) {
185: if (!(whom = getlogin()))
186: whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
187: (void)gethostname(hostname, sizeof(hostname));
188: (void)time(&now);
189: lt = localtime(&now);
1.11 d 190: if ((ttynam = ttyname(STDERR_FILENO)) == NULL)
191: ttynam = "(not a tty)";
1.1 deraadt 192:
193: /*
194: * all this stuff is to blank out a square for the message;
195: * we wrap message lines at column 79, not 80, because some
196: * terminals wrap after 79, some do not, and we can't tell.
197: * Which means that we may leave a non-blank character
198: * in column 80, but that can't be helped.
199: */
200: (void)fprintf(fp, "\r%79s\r\n", " ");
1.3 deraadt 201: (void)snprintf(lbuf, sizeof lbuf,
202: "Broadcast Message from %s@%s", whom, hostname);
1.1 deraadt 203: (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf);
1.3 deraadt 204: (void)snprintf(lbuf, sizeof lbuf,
1.11 d 205: " (%s) at %d:%02d ...", ttynam,
1.1 deraadt 206: lt->tm_hour, lt->tm_min);
207: (void)fprintf(fp, "%-79.79s\r\n", lbuf);
208: }
209: (void)fprintf(fp, "%79s\r\n", " ");
210:
1.13 deraadt 211: if (fname) {
212: gid_t egid = getegid();
213:
214: setegid(getgid());
215: if (freopen(fname, "r", stdin) == NULL)
216: errx(1, "can't read %s.", fname);
217: setegid(egid);
218: }
1.1 deraadt 219: while (fgets(lbuf, sizeof(lbuf), stdin))
220: for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
1.5 deraadt 221: vis(tmpbuf, ch, VIS_SAFE|VIS_NOSLASH, p[1]);
1.4 deraadt 222: if (cnt == 79+1-strlen(tmpbuf) || ch == '\n') {
223: for (; cnt < 79+1-strlen(tmpbuf); ++cnt)
1.1 deraadt 224: putc(' ', fp);
225: putc('\r', fp);
226: putc('\n', fp);
227: cnt = -1;
228: }
1.4 deraadt 229: if (ch != '\n') {
230: int xx;
231:
232: for (xx = 0; tmpbuf[xx]; xx++)
233: putc(tmpbuf[xx], fp);
234: }
1.1 deraadt 235: }
236: (void)fprintf(fp, "%79s\r\n", " ");
237: rewind(fp);
238:
1.9 form 239: if (fstat(fd, &sbuf))
1.13 deraadt 240: errx(1, "can't stat temporary file.");
1.1 deraadt 241: mbufsize = sbuf.st_size;
1.9 form 242: if (!(mbuf = malloc((u_int)mbufsize)))
1.13 deraadt 243: errx(1, "out of memory.");
1.9 form 244: if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize)
1.13 deraadt 245: errx(1, "can't read temporary file.");
1.1 deraadt 246: (void)close(fd);
1.15 ! millert 247: }
! 248:
! 249: void
! 250: addgroup(struct group *grp, char *name)
! 251: {
! 252: int i;
! 253: struct wallgroup *g;
! 254:
! 255: for (i = 0; grp->gr_mem[i]; i++)
! 256: ;
! 257:
! 258: g = (struct wallgroup *)malloc(sizeof *g);
! 259: if (g == NULL)
! 260: errx(1, "out of memory.");
! 261: g->gid = grp->gr_gid;
! 262: g->name = name;
! 263: g->mem = (char **)malloc(i + 1);
! 264: if (g->mem == NULL)
! 265: errx(1, "out of memory.");
! 266: for (i = 0; grp->gr_mem[i] != NULL; i++) {
! 267: g->mem[i] = strdup(grp->gr_mem[i]);
! 268: if (g->mem[i] == NULL)
! 269: errx(1, "out of memory.");
! 270: }
! 271: g->mem[i] = NULL;
! 272: g->next = grouplist;
! 273: grouplist = g;
! 274: }
! 275:
! 276: void
! 277: usage(void)
! 278: {
! 279: extern char *__progname;
! 280:
! 281: (void)fprintf(stderr, "usage: %s [-g group] [file]\n", __progname);
! 282: exit(1);
1.1 deraadt 283: }