1 /* 2 * Copyright (c) 1980 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef lint 35 char copyright[] = 36 "@(#) Copyright (c) 1980 Regents of the University of California.\n\ 37 All rights reserved.\n"; 38 #endif /* not lint */ 39 40 #ifndef lint 41 static char sccsid[] = "@(#)comsat.c 5.24 (Berkeley) 2/25/91"; 42 #endif /* not lint */ 43 44 #include <sys/param.h> 45 #include <sys/socket.h> 46 #include <sys/stat.h> 47 #include <sys/file.h> 48 #include <sys/wait.h> 49 50 #include <netinet/in.h> 51 52 #include <stdio.h> 53 #include <sgtty.h> 54 #include <utmp.h> 55 #include <signal.h> 56 #include <errno.h> 57 #include <netdb.h> 58 #include <syslog.h> 59 #include <ctype.h> 60 #include <string.h> 61 #include <paths.h> 62 63 int debug = 0; 64 #define dsyslog if (debug) syslog 65 66 #define MAXIDLE 120 67 68 char hostname[MAXHOSTNAMELEN]; 69 struct utmp *utmp = NULL; 70 time_t lastmsgtime, time(); 71 int nutmp, uf; 72 73 /* ARGSUSED */ 74 main(argc, argv) 75 int argc; 76 char **argv; 77 { 78 extern int errno; 79 register int cc; 80 char msgbuf[100]; 81 struct sockaddr_in from; 82 int fromlen; 83 void onalrm(), reapchildren(); 84 85 /* verify proper invocation */ 86 fromlen = sizeof(from); 87 if (getsockname(0, (struct sockaddr *)&from, &fromlen) < 0) { 88 (void)fprintf(stderr, 89 "comsat: getsockname: %s.\n", strerror(errno)); 90 exit(1); 91 } 92 openlog("comsat", LOG_PID, LOG_DAEMON); 93 if (chdir(_PATH_MAILDIR)) { 94 syslog(LOG_ERR, "chdir: %s: %m", _PATH_MAILDIR); 95 exit(1); 96 } 97 if ((uf = open(_PATH_UTMP, O_RDONLY, 0)) < 0) { 98 syslog(LOG_ERR, ".main: %s: %m", _PATH_UTMP); 99 (void) recv(0, msgbuf, sizeof(msgbuf) - 1, 0); 100 exit(1); 101 } 102 (void)time(&lastmsgtime); 103 (void)gethostname(hostname, sizeof(hostname)); 104 onalrm(); 105 (void)signal(SIGALRM, onalrm); 106 (void)signal(SIGTTOU, SIG_IGN); 107 (void)signal(SIGCHLD, reapchildren); 108 for (;;) { 109 cc = recv(0, msgbuf, sizeof(msgbuf) - 1, 0); 110 if (cc <= 0) { 111 if (errno != EINTR) 112 sleep(1); 113 errno = 0; 114 continue; 115 } 116 if (!nutmp) /* no one has logged in yet */ 117 continue; 118 sigblock(sigmask(SIGALRM)); 119 msgbuf[cc] = 0; 120 (void)time(&lastmsgtime); 121 mailfor(msgbuf); 122 sigsetmask(0L); 123 } 124 } 125 126 void 127 reapchildren() 128 { 129 while (wait3((int *)NULL, WNOHANG, (struct rusage *)NULL) > 0); 130 } 131 132 void 133 onalrm() 134 { 135 static u_int utmpsize; /* last malloced size for utmp */ 136 static u_int utmpmtime; /* last modification time for utmp */ 137 struct stat statbf; 138 off_t lseek(); 139 char *malloc(), *realloc(); 140 141 if (time((time_t *)NULL) - lastmsgtime >= MAXIDLE) 142 exit(0); 143 (void)alarm((u_int)15); 144 (void)fstat(uf, &statbf); 145 if (statbf.st_mtime > utmpmtime) { 146 utmpmtime = statbf.st_mtime; 147 if (statbf.st_size > utmpsize) { 148 utmpsize = statbf.st_size + 10 * sizeof(struct utmp); 149 if (utmp) 150 utmp = (struct utmp *)realloc((char *)utmp, utmpsize); 151 else 152 utmp = (struct utmp *)malloc(utmpsize); 153 if (!utmp) { 154 syslog(LOG_ERR, "malloc failed"); 155 exit(1); 156 } 157 } 158 (void)lseek(uf, 0L, L_SET); 159 nutmp = read(uf, utmp, (int)statbf.st_size)/sizeof(struct utmp); 160 } 161 } 162 163 mailfor(name) 164 char *name; 165 { 166 register struct utmp *utp = &utmp[nutmp]; 167 register char *cp; 168 off_t offset; 169 170 if (!(cp = index(name, '@'))) 171 return; 172 *cp = '\0'; 173 offset = atoi(cp + 1); 174 while (--utp >= utmp) 175 if (!strncmp(utp->ut_name, name, sizeof(utmp[0].ut_name))) 176 notify(utp, offset); 177 } 178 179 static char *cr; 180 181 notify(utp, offset) 182 register struct utmp *utp; 183 off_t offset; 184 { 185 static char tty[20] = _PATH_DEV; 186 struct sgttyb gttybuf; 187 struct stat stb; 188 FILE *tp; 189 char name[sizeof(utmp[0].ut_name) + 1]; 190 191 (void)strncpy(tty + sizeof(_PATH_DEV) - 1, utp->ut_line, 192 sizeof(utp->ut_line)); 193 if (stat(tty, &stb) || !(stb.st_mode & S_IEXEC)) { 194 dsyslog(LOG_DEBUG, "%s: wrong mode on %s", utp->ut_name, tty); 195 return; 196 } 197 dsyslog(LOG_DEBUG, "notify %s on %s\n", utp->ut_name, tty); 198 if (fork()) 199 return; 200 (void)signal(SIGALRM, SIG_DFL); 201 (void)alarm((u_int)30); 202 if ((tp = fopen(tty, "w")) == NULL) { 203 dsyslog(LOG_ERR, "fopen of tty %s failed", tty); 204 _exit(-1); 205 } 206 (void)ioctl(fileno(tp), TIOCGETP, >tybuf); 207 cr = (gttybuf.sg_flags&CRMOD) && !(gttybuf.sg_flags&RAW) ? 208 "\n" : "\n\r"; 209 (void)strncpy(name, utp->ut_name, sizeof(utp->ut_name)); 210 name[sizeof(name) - 1] = '\0'; 211 (void)fprintf(tp, "%s\007New mail for %s@%.*s\007 has arrived:%s----%s", 212 cr, name, sizeof(hostname), hostname, cr, cr); 213 jkfprintf(tp, name, offset); 214 (void)fclose(tp); 215 _exit(0); 216 } 217 218 jkfprintf(tp, name, offset) 219 register FILE *tp; 220 char name[]; 221 off_t offset; 222 { 223 register char *cp, ch; 224 register FILE *fi; 225 register int linecnt, charcnt, inheader; 226 char line[BUFSIZ]; 227 228 if ((fi = fopen(name, "r")) == NULL) 229 return; 230 (void)fseek(fi, offset, L_SET); 231 /* 232 * Print the first 7 lines or 560 characters of the new mail 233 * (whichever comes first). Skip header crap other than 234 * From, Subject, To, and Date. 235 */ 236 linecnt = 7; 237 charcnt = 560; 238 inheader = 1; 239 while (fgets(line, sizeof(line), fi) != NULL) { 240 if (inheader) { 241 if (line[0] == '\n') { 242 inheader = 0; 243 continue; 244 } 245 if (line[0] == ' ' || line[0] == '\t' || 246 strncmp(line, "From:", 5) && 247 strncmp(line, "Subject:", 8)) 248 continue; 249 } 250 if (linecnt <= 0 || charcnt <= 0) { 251 (void)fprintf(tp, "...more...%s", cr); 252 return; 253 } 254 /* strip weird stuff so can't trojan horse stupid terminals */ 255 for (cp = line; (ch = *cp) && ch != '\n'; ++cp, --charcnt) { 256 ch = toascii(ch); 257 if (!isprint(ch) && !isspace(ch)) 258 ch |= 0x40; 259 (void)fputc(ch, tp); 260 } 261 (void)fputs(cr, tp); 262 --linecnt; 263 } 264 (void)fprintf(tp, "----%s\n", cr); 265 } 266