[BACK]Return to wall.c CVS log [TXT][DIR] Up to [local] / src / usr.bin / wall

Annotation of src/usr.bin/wall/wall.c, Revision 1.34

1.34    ! deraadt     1: /*     $OpenBSD: wall.c,v 1.33 2018/08/07 18:28:05 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.
1.18      millert    16:  * 3. Neither the name of the University nor the names of its contributors
1.1       deraadt    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:
1.29      benno      38: #include <sys/queue.h>
1.1       deraadt    39: #include <sys/stat.h>
                     40: #include <sys/time.h>
                     41: #include <sys/uio.h>
                     42:
1.30      martijn    43: #include <ctype.h>
                     44: #include <err.h>
                     45: #include <grp.h>
                     46: #include <limits.h>
1.1       deraadt    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:
1.6       deraadt    55: struct wallgroup {
1.15      millert    56:        gid_t   gid;
                     57:        char    *name;
                     58:        char    **mem;
1.6       deraadt    59:        struct wallgroup *next;
                     60: } *grouplist;
                     61:
1.29      benno      62: struct utmptty {
                     63:        char    *tty;
                     64:        SLIST_ENTRY(utmptty) next;
                     65: };
                     66:
1.15      millert    67: void   makemsg(char *);
                     68: void   addgroup(struct group *, char *);
                     69: char   *ttymsg(struct iovec *, int, char *, int);
                     70: __dead void usage(void);
1.30      martijn    71: static int isu8cont(unsigned char);
1.1       deraadt    72:
                     73: int nobanner;
                     74: int mbufsize;
                     75: char *mbuf;
                     76:
                     77: /* ARGSUSED */
                     78: int
1.15      millert    79: main(int argc, char **argv)
1.1       deraadt    80: {
1.15      millert    81:        FILE *fp;
                     82:        int ch, ingroup;
1.1       deraadt    83:        struct iovec iov;
                     84:        struct utmp utmp;
1.15      millert    85:        char *p, **mem;
1.1       deraadt    86:        char line[sizeof(utmp.ut_line) + 1];
1.15      millert    87:        char username[sizeof(utmp.ut_name) + 1];
                     88:        struct passwd *pw;
                     89:        struct group *grp;
1.6       deraadt    90:        struct wallgroup *g;
1.29      benno      91:        struct utmptty *un;
                     92:        SLIST_HEAD(,utmptty) utmphead;
                     93:        SLIST_INIT(&utmphead);
1.1       deraadt    94:
1.8       millert    95:        while ((ch = getopt(argc, argv, "ng:")) != -1)
1.1       deraadt    96:                switch (ch) {
                     97:                case 'n':
                     98:                        /* undoc option for shutdown: suppress banner */
1.15      millert    99:                        pw = getpwnam("nobody");
                    100:                        if (geteuid() == 0 || (pw && getuid() == pw->pw_uid))
1.1       deraadt   101:                                nobanner = 1;
                    102:                        break;
1.6       deraadt   103:                case 'g':
1.15      millert   104:                        if ((grp = getgrnam(optarg)) == NULL)
                    105:                                errx(1, "unknown group `%s'", optarg);
                    106:                        addgroup(grp, optarg);
1.6       deraadt   107:                        break;
1.1       deraadt   108:                default:
1.15      millert   109:                        usage();
1.1       deraadt   110:                }
                    111:        argc -= optind;
                    112:        argv += optind;
                    113:        if (argc > 1)
1.15      millert   114:                usage();
1.6       deraadt   115:
1.1       deraadt   116:        makemsg(*argv);
                    117:
1.33      deraadt   118:        if (unveil(_PATH_UTMP, "r") == -1)
                    119:                err(1, "unveil");
                    120:        if (unveil(_PATH_DEV, "w") == -1)
1.34    ! deraadt   121:                err(1, "unveil");
        !           122:        if (unveil(_PATH_DEVDB, "r") == -1)
1.33      deraadt   123:                err(1, "unveil");
1.29      benno     124:        if (pledge("stdio rpath wpath getpw proc", NULL) == -1)
                    125:                err(1, "pledge");
                    126:
1.9       form      127:        if (!(fp = fopen(_PATH_UTMP, "r")))
1.21      henning   128:                err(1, "cannot read %s", _PATH_UTMP);
1.1       deraadt   129:        iov.iov_base = mbuf;
                    130:        iov.iov_len = mbufsize;
1.29      benno     131:
1.15      millert   132:        while (fread(&utmp, sizeof(utmp), 1, fp) == 1) {
1.16      deraadt   133:                if (!utmp.ut_name[0])
1.1       deraadt   134:                        continue;
1.6       deraadt   135:                if (grouplist) {
1.15      millert   136:                        ingroup = 0;
                    137:                        strncpy(username, utmp.ut_name, sizeof(utmp.ut_name));
                    138:                        username[sizeof(utmp.ut_name)] = '\0';
1.6       deraadt   139:                        pw = getpwnam(username);
                    140:                        if (!pw)
                    141:                                continue;
                    142:                        for (g = grouplist; g && ingroup == 0; g = g->next) {
                    143:                                if (g->gid == pw->pw_gid)
                    144:                                        ingroup = 1;
1.15      millert   145:                                for (mem = g->mem; *mem && ingroup == 0; mem++)
                    146:                                        if (strcmp(username, *mem) == 0)
1.6       deraadt   147:                                                ingroup = 1;
                    148:                        }
                    149:                        if (ingroup == 0)
                    150:                                continue;
                    151:                }
1.1       deraadt   152:                strncpy(line, utmp.ut_line, sizeof(utmp.ut_line));
                    153:                line[sizeof(utmp.ut_line)] = '\0';
1.29      benno     154:                un = malloc(sizeof(struct utmptty));
                    155:                if (un == NULL)
                    156:                        err(1, "malloc");
                    157:                un->tty = strndup(line, sizeof(utmp.ut_line));
                    158:                if (un->tty == NULL)
                    159:                        err(1, "strndup");
                    160:                SLIST_INSERT_HEAD(&utmphead, un, next);
                    161:        }
                    162:        fclose(fp);
                    163:
                    164:        if (pledge("stdio rpath wpath proc", NULL) == -1)
                    165:                err(1, "pledge");
                    166:
                    167:        SLIST_FOREACH(un, &utmphead, next) {
                    168:                if ((p = ttymsg(&iov, 1, un->tty, 60*5)) != NULL)
1.13      deraadt   169:                        warnx("%s", p);
1.1       deraadt   170:        }
1.29      benno     171:
1.1       deraadt   172:        exit(0);
                    173: }
                    174:
                    175: void
1.15      millert   176: makemsg(char *fname)
1.1       deraadt   177: {
1.30      martijn   178:        int cnt;
1.1       deraadt   179:        struct tm *lt;
                    180:        struct passwd *pw;
                    181:        struct stat sbuf;
1.19      deraadt   182:        time_t now;
1.1       deraadt   183:        FILE *fp;
                    184:        int fd;
1.26      deraadt   185:        char *p, *whom, hostname[HOST_NAME_MAX+1], lbuf[100], tmpname[PATH_MAX];
1.11      d         186:        char *ttynam;
1.30      martijn   187:        unsigned char ch;
1.1       deraadt   188:
1.20      avsm      189:        snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXXXXXX", _PATH_TMP);
1.15      millert   190:        if ((fd = mkstemp(tmpname)) >= 0) {
                    191:                (void)unlink(tmpname);
                    192:                fp = fdopen(fd, "r+");
                    193:        }
                    194:        if (fd == -1 || fp == NULL)
1.21      henning   195:                err(1, "can't open temporary file");
1.1       deraadt   196:
                    197:        if (!nobanner) {
                    198:                if (!(whom = getlogin()))
                    199:                        whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
                    200:                (void)gethostname(hostname, sizeof(hostname));
                    201:                (void)time(&now);
                    202:                lt = localtime(&now);
1.11      d         203:                if ((ttynam = ttyname(STDERR_FILENO)) == NULL)
                    204:                        ttynam = "(not a tty)";
1.1       deraadt   205:
                    206:                /*
                    207:                 * all this stuff is to blank out a square for the message;
                    208:                 * we wrap message lines at column 79, not 80, because some
                    209:                 * terminals wrap after 79, some do not, and we can't tell.
                    210:                 * Which means that we may leave a non-blank character
                    211:                 * in column 80, but that can't be helped.
                    212:                 */
                    213:                (void)fprintf(fp, "\r%79s\r\n", " ");
1.3       deraadt   214:                (void)snprintf(lbuf, sizeof lbuf,
                    215:                    "Broadcast Message from %s@%s", whom, hostname);
1.1       deraadt   216:                (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf);
1.3       deraadt   217:                (void)snprintf(lbuf, sizeof lbuf,
1.11      d         218:                    "        (%s) at %d:%02d ...", ttynam,
1.1       deraadt   219:                    lt->tm_hour, lt->tm_min);
                    220:                (void)fprintf(fp, "%-79.79s\r\n", lbuf);
                    221:        }
                    222:        (void)fprintf(fp, "%79s\r\n", " ");
                    223:
1.13      deraadt   224:        if (fname) {
                    225:                gid_t egid = getegid();
                    226:
                    227:                setegid(getgid());
                    228:                if (freopen(fname, "r", stdin) == NULL)
1.21      henning   229:                        err(1, "can't read %s", fname);
1.13      deraadt   230:                setegid(egid);
                    231:        }
1.1       deraadt   232:        while (fgets(lbuf, sizeof(lbuf), stdin))
                    233:                for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
1.30      martijn   234:                        if (cnt == 79 || ch == '\n') {
                    235:                                for (; cnt < 79; ++cnt)
1.1       deraadt   236:                                        putc(' ', fp);
                    237:                                putc('\r', fp);
                    238:                                putc('\n', fp);
                    239:                                cnt = -1;
1.30      martijn   240:                        } else if (!isu8cont(ch))
1.32      martijn   241:                                putc(isprint(ch) || isspace(ch) || ch == '\a' ?
1.30      martijn   242:                                    ch : '?', fp);
1.1       deraadt   243:                }
                    244:        (void)fprintf(fp, "%79s\r\n", " ");
                    245:        rewind(fp);
                    246:
1.9       form      247:        if (fstat(fd, &sbuf))
1.21      henning   248:                err(1, "can't stat temporary file");
1.1       deraadt   249:        mbufsize = sbuf.st_size;
1.22      tom       250:        mbuf = malloc((u_int)mbufsize);
                    251:        if (mbuf == NULL)
                    252:                err(1, NULL);
1.9       form      253:        if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize)
1.21      henning   254:                err(1, "can't read temporary file");
1.1       deraadt   255:        (void)close(fd);
1.15      millert   256: }
                    257:
                    258: void
                    259: addgroup(struct group *grp, char *name)
                    260: {
                    261:        int i;
                    262:        struct wallgroup *g;
                    263:
                    264:        for (i = 0; grp->gr_mem[i]; i++)
                    265:                ;
                    266:
1.27      deraadt   267:        g = malloc(sizeof *g);
1.15      millert   268:        if (g == NULL)
1.22      tom       269:                err(1, NULL);
1.15      millert   270:        g->gid = grp->gr_gid;
                    271:        g->name = name;
1.27      deraadt   272:        g->mem = calloc(i + 1, sizeof(char *));
1.15      millert   273:        if (g->mem == NULL)
1.22      tom       274:                err(1, NULL);
1.15      millert   275:        for (i = 0; grp->gr_mem[i] != NULL; i++) {
                    276:                g->mem[i] = strdup(grp->gr_mem[i]);
                    277:                if (g->mem[i] == NULL)
1.22      tom       278:                        err(1, NULL);
1.15      millert   279:        }
                    280:        g->mem[i] = NULL;
                    281:        g->next = grouplist;
                    282:        grouplist = g;
                    283: }
                    284:
                    285: void
                    286: usage(void)
                    287: {
                    288:        extern char *__progname;
                    289:
                    290:        (void)fprintf(stderr, "usage: %s [-g group] [file]\n", __progname);
                    291:        exit(1);
1.30      martijn   292: }
                    293:
                    294: static int
                    295: isu8cont(unsigned char c)
                    296: {
                    297:        return (c & (0x80 | 0x40)) == 0x80;
1.1       deraadt   298: }