comsat.c revision 1.3
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[] = "from: @(#)comsat.c 5.24 (Berkeley) 2/25/91";*/ 42 static char rcsid[] = "$Id: comsat.c,v 1.3 1994/01/30 18:32:39 briggs Exp $"; 43 #endif /* not lint */ 44 45 #include <sys/param.h> 46 #include <sys/socket.h> 47 #include <sys/stat.h> 48 #include <sys/file.h> 49 #include <sys/wait.h> 50 51 #include <netinet/in.h> 52 53 #include <stdio.h> 54 #include <sgtty.h> 55 #include <utmp.h> 56 #include <signal.h> 57 #include <errno.h> 58 #include <netdb.h> 59 #include <syslog.h> 60 #include <ctype.h> 61 #include <string.h> 62 #include <paths.h> 63 64 int debug = 0; 65 #define dsyslog if (debug) syslog 66 67 #define MAXIDLE 120 68 69 char hostname[MAXHOSTNAMELEN]; 70 struct utmp *utmp = NULL; 71 time_t lastmsgtime, time(); 72 int nutmp, uf; 73 74 /* ARGSUSED */ 75 main(argc, argv) 76 int argc; 77 char **argv; 78 { 79 extern int errno; 80 register int cc; 81 char msgbuf[100]; 82 struct sockaddr_in from; 83 int fromlen; 84 void onalrm(), reapchildren(); 85 86 /* verify proper invocation */ 87 fromlen = sizeof(from); 88 if (getsockname(0, (struct sockaddr *)&from, &fromlen) < 0) { 89 (void)fprintf(stderr, 90 "comsat: getsockname: %s.\n", strerror(errno)); 91 exit(1); 92 } 93 openlog("comsat", LOG_PID, LOG_DAEMON); 94 if (chdir(_PATH_MAILDIR)) { 95 syslog(LOG_ERR, "chdir: %s: %m", _PATH_MAILDIR); 96 exit(1); 97 } 98 if ((uf = open(_PATH_UTMP, O_RDONLY, 0)) < 0) { 99 syslog(LOG_ERR, ".main: %s: %m", _PATH_UTMP); 100 (void) recv(0, msgbuf, sizeof(msgbuf) - 1, 0); 101 exit(1); 102 } 103 (void)time(&lastmsgtime); 104 (void)gethostname(hostname, sizeof(hostname)); 105 onalrm(); 106 (void)signal(SIGALRM, onalrm); 107 (void)signal(SIGTTOU, SIG_IGN); 108 (void)signal(SIGCHLD, reapchildren); 109 for (;;) { 110 cc = recv(0, msgbuf, sizeof(msgbuf) - 1, 0); 111 if (cc <= 0) { 112 if (errno != EINTR) 113 sleep(1); 114 errno = 0; 115 continue; 116 } 117 if (!nutmp) /* no one has logged in yet */ 118 continue; 119 sigblock(sigmask(SIGALRM)); 120 msgbuf[cc] = 0; 121 (void)time(&lastmsgtime); 122 mailfor(msgbuf); 123 sigsetmask(0L); 124 } 125 } 126 127 void 128 reapchildren() 129 { 130 while (wait3((int *)NULL, WNOHANG, (struct rusage *)NULL) > 0); 131 } 132 133 void 134 onalrm() 135 { 136 static u_int utmpsize; /* last malloced size for utmp */ 137 static u_int utmpmtime; /* last modification time for utmp */ 138 struct stat statbf; 139 off_t lseek(); 140 char *malloc(), *realloc(); 141 142 if (time((time_t *)NULL) - lastmsgtime >= MAXIDLE) 143 exit(0); 144 (void)alarm((u_int)15); 145 (void)fstat(uf, &statbf); 146 if (statbf.st_mtime > utmpmtime) { 147 utmpmtime = statbf.st_mtime; 148 if (statbf.st_size > utmpsize) { 149 utmpsize = statbf.st_size + 10 * sizeof(struct utmp); 150 if (utmp) 151 utmp = (struct utmp *)realloc((char *)utmp, utmpsize); 152 else 153 utmp = (struct utmp *)malloc(utmpsize); 154 if (!utmp) { 155 syslog(LOG_ERR, "malloc failed"); 156 exit(1); 157 } 158 } 159 (void)lseek(uf, 0L, L_SET); 160 nutmp = read(uf, utmp, (int)statbf.st_size)/sizeof(struct utmp); 161 } 162 } 163 164 mailfor(name) 165 char *name; 166 { 167 register struct utmp *utp = &utmp[nutmp]; 168 register char *cp; 169 off_t offset; 170 171 if (!(cp = index(name, '@'))) 172 return; 173 *cp = '\0'; 174 offset = atoi(cp + 1); 175 while (--utp >= utmp) 176 if (!strncmp(utp->ut_name, name, sizeof(utmp[0].ut_name))) 177 notify(utp, offset); 178 } 179 180 static char *cr; 181 182 notify(utp, offset) 183 register struct utmp *utp; 184 off_t offset; 185 { 186 static char tty[20] = _PATH_DEV; 187 struct sgttyb gttybuf; 188 struct stat stb; 189 FILE *tp; 190 char name[sizeof(utmp[0].ut_name) + 1]; 191 192 (void)strncpy(tty + sizeof(_PATH_DEV) - 1, utp->ut_line, 193 sizeof(utp->ut_line)); 194 if (stat(tty, &stb) || !(stb.st_mode & S_IEXEC)) { 195 dsyslog(LOG_DEBUG, "%s: wrong mode on %s", utp->ut_name, tty); 196 return; 197 } 198 dsyslog(LOG_DEBUG, "notify %s on %s\n", utp->ut_name, tty); 199 if (fork()) 200 return; 201 (void)signal(SIGALRM, SIG_DFL); 202 (void)alarm((u_int)30); 203 if ((tp = fopen(tty, "w")) == NULL) { 204 dsyslog(LOG_ERR, "fopen of tty %s failed", tty); 205 _exit(-1); 206 } 207 (void)ioctl(fileno(tp), TIOCGETP, >tybuf); 208 cr = (gttybuf.sg_flags&CRMOD) && !(gttybuf.sg_flags&RAW) ? 209 "\n" : "\n\r"; 210 (void)strncpy(name, utp->ut_name, sizeof(utp->ut_name)); 211 name[sizeof(name) - 1] = '\0'; 212 (void)fprintf(tp, "%s\007New mail for %s@%.*s\007 has arrived:%s----%s", 213 cr, name, sizeof(hostname), hostname, cr, cr); 214 jkfprintf(tp, name, offset); 215 (void)fclose(tp); 216 _exit(0); 217 } 218 219 jkfprintf(tp, name, offset) 220 register FILE *tp; 221 char name[]; 222 off_t offset; 223 { 224 register char *cp, ch; 225 register FILE *fi; 226 register int linecnt, charcnt, inheader; 227 struct stat st; 228 char line[BUFSIZ]; 229 230 if (lstat(name, &st) != 0) { 231 syslog(LOG_ERR, "Unable to stat mail file."); 232 return; 233 } 234 if (!(S_ISREG(st.st_mode))) { 235 syslog(LOG_ERR, "Mail file is not a regular file."); 236 return; 237 } 238 if ((fi = fopen(name, "r")) == NULL) 239 return; 240 (void)fseek(fi, offset, L_SET); 241 /* 242 * Print the first 7 lines or 560 characters of the new mail 243 * (whichever comes first). Skip header crap other than 244 * From, Subject, To, and Date. 245 */ 246 linecnt = 7; 247 charcnt = 560; 248 inheader = 1; 249 while (fgets(line, sizeof(line), fi) != NULL) { 250 if (inheader) { 251 if (line[0] == '\n') { 252 inheader = 0; 253 continue; 254 } 255 if (line[0] == ' ' || line[0] == '\t' || 256 strncmp(line, "From:", 5) && 257 strncmp(line, "Subject:", 8)) 258 continue; 259 } 260 if (linecnt <= 0 || charcnt <= 0) { 261 (void)fprintf(tp, "...more...%s", cr); 262 return; 263 } 264 /* strip weird stuff so can't trojan horse stupid terminals */ 265 for (cp = line; (ch = *cp) && ch != '\n'; ++cp, --charcnt) { 266 ch = toascii(ch); 267 if (!isprint(ch) && !isspace(ch)) 268 ch |= 0x40; 269 (void)fputc(ch, tp); 270 } 271 (void)fputs(cr, tp); 272 --linecnt; 273 } 274 (void)fprintf(tp, "----%s\n", cr); 275 } 276
Indexes created Wed Sep 24 02:09:48 GMT 2025