vacation.c revision 1.24
1 /* $NetBSD: vacation.c,v 1.24 2003/08/07 11:16:59 agc Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1987, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 34 #ifndef lint 35 __COPYRIGHT("@(#) Copyright (c) 1983, 1987, 1993\n\ 36 The Regents of the University of California. All rights reserved.\n"); 37 #endif /* not lint */ 38 39 #ifndef lint 40 #if 0 41 static char sccsid[] = "@(#)vacation.c 8.2 (Berkeley) 1/26/94"; 42 #endif 43 __RCSID("$NetBSD: vacation.c,v 1.24 2003/08/07 11:16:59 agc Exp $"); 44 #endif /* not lint */ 45 46 /* 47 ** Vacation 48 ** Copyright (c) 1983 Eric P. Allman 49 ** Berkeley, California 50 */ 51 52 #include <sys/param.h> 53 #include <sys/stat.h> 54 55 #include <ctype.h> 56 #include <db.h> 57 #include <err.h> 58 #include <errno.h> 59 #include <fcntl.h> 60 #include <paths.h> 61 #include <pwd.h> 62 #include <stdio.h> 63 #include <stdlib.h> 64 #include <string.h> 65 #include <syslog.h> 66 #include <time.h> 67 #include <tzfile.h> 68 #include <unistd.h> 69 70 /* 71 * VACATION -- return a message to the sender when on vacation. 72 * 73 * This program is invoked as a message receiver. It returns a 74 * message specified by the user to whomever sent the mail, taking 75 * care not to return a message too often to prevent "I am on 76 * vacation" loops. 77 */ 78 79 #define MAXLINE 1024 /* max line from mail header */ 80 #define VDB ".vacation.db" /* dbm's database */ 81 #define VMSG ".vacation.msg" /* vacation message */ 82 83 typedef struct alias { 84 struct alias *next; 85 const char *name; 86 } alias_t; 87 alias_t *names; 88 89 DB *db; 90 char from[MAXLINE]; 91 static int tflag = 0; 92 #define APPARENTLY_TO 1 93 #define DELIVERED_TO 2 94 95 int main(int, char **); 96 int junkmail(void); 97 int nsearch(const char *, const char *); 98 void readheaders(void); 99 int recent(void); 100 void sendmessage(const char *); 101 void setinterval(time_t); 102 void setreply(void); 103 void usage(void); 104 105 int 106 main(int argc, char **argv) 107 { 108 struct passwd *pw; 109 alias_t *cur; 110 time_t interval; 111 int ch, iflag; 112 char *p; 113 114 opterr = iflag = 0; 115 interval = -1; 116 openlog("vacation", 0, LOG_USER); 117 while ((ch = getopt(argc, argv, "a:Iir:t:")) != -1) 118 switch((char)ch) { 119 case 'a': /* alias */ 120 if (!(cur = (alias_t *)malloc((size_t)sizeof(alias_t)))) 121 break; 122 cur->name = optarg; 123 cur->next = names; 124 names = cur; 125 break; 126 case 'I': /* backward compatible */ 127 case 'i': /* init the database */ 128 iflag = 1; 129 break; 130 case 'r': 131 if (isdigit((unsigned char)*optarg)) { 132 interval = atol(optarg) * SECSPERDAY; 133 if (interval < 0) 134 usage(); 135 } 136 else 137 interval = (time_t)LONG_MAX; /* XXX */ 138 break; 139 case 't': 140 for (p = optarg; *p; p++) 141 switch (*p) { 142 case 'A': 143 tflag |= APPARENTLY_TO; 144 break; 145 case 'D': 146 tflag |= DELIVERED_TO; 147 break; 148 default: 149 errx(1, "Unknown -t option `%c'", *p); 150 } 151 break; 152 case '?': 153 default: 154 usage(); 155 } 156 argc -= optind; 157 argv += optind; 158 159 if (argc != 1) { 160 if (!iflag) 161 usage(); 162 if (!(pw = getpwuid(getuid()))) { 163 syslog(LOG_ERR, 164 "vacation: no such user uid %u.", getuid()); 165 exit(1); 166 } 167 } 168 else if (!(pw = getpwnam(*argv))) { 169 syslog(LOG_ERR, "vacation: no such user %s.", *argv); 170 exit(1); 171 } 172 if (chdir(pw->pw_dir)) { 173 syslog(LOG_ERR, 174 "vacation: no such directory %s.", pw->pw_dir); 175 exit(1); 176 } 177 178 db = dbopen(VDB, O_CREAT|O_RDWR | (iflag ? O_TRUNC : 0), 179 S_IRUSR|S_IWUSR, DB_HASH, NULL); 180 if (!db) { 181 syslog(LOG_ERR, "vacation: %s: %m", VDB); 182 exit(1); 183 } 184 185 if (interval != -1) 186 setinterval(interval); 187 188 if (iflag) { 189 (void)(db->close)(db); 190 exit(0); 191 } 192 193 if (!(cur = malloc((size_t)sizeof(alias_t)))) 194 exit(1); 195 cur->name = pw->pw_name; 196 cur->next = names; 197 names = cur; 198 199 readheaders(); 200 if (!recent()) { 201 setreply(); 202 (void)(db->close)(db); 203 sendmessage(pw->pw_name); 204 } 205 else 206 (void)(db->close)(db); 207 exit(0); 208 /* NOTREACHED */ 209 } 210 211 /* 212 * readheaders -- 213 * read mail headers 214 */ 215 void 216 readheaders(void) 217 { 218 alias_t *cur; 219 char *p; 220 int tome, cont; 221 char buf[MAXLINE]; 222 223 cont = tome = 0; 224 while (fgets(buf, sizeof(buf), stdin) && *buf != '\n') 225 switch(*buf) { 226 case 'F': /* "From " */ 227 /* XXX should instead consider Return-Path: and Sender: */ 228 cont = 0; 229 if (!strncmp(buf, "From ", 5)) { 230 for (p = buf + 5; *p && *p != ' '; ++p); 231 *p = '\0'; 232 (void)strlcpy(from, buf + 5, sizeof(from)); 233 if ((p = strchr(from, '\n'))) 234 *p = '\0'; 235 if (junkmail()) 236 exit(0); 237 } 238 break; 239 case 'P': /* "Precedence:" */ 240 cont = 0; 241 if (strncasecmp(buf, "Precedence", 10) || 242 (buf[10] != ':' && buf[10] != ' ' && 243 buf[10] != '\t')) 244 break; 245 if (!(p = strchr(buf, ':'))) 246 break; 247 while (*++p && isspace((unsigned char)*p)); 248 if (!*p) 249 break; 250 if (!strncasecmp(p, "junk", 4) || 251 !strncasecmp(p, "bulk", 4) || 252 !strncasecmp(p, "list", 4)) 253 exit(0); 254 break; 255 case 'C': /* "Cc:" */ 256 if (strncmp(buf, "Cc:", 3)) 257 break; 258 cont = 1; 259 goto findme; 260 case 'T': /* "To:" */ 261 if (strncmp(buf, "To:", 3)) 262 break; 263 cont = 1; 264 goto findme; 265 case 'A': 266 if ((tflag & APPARENTLY_TO) == 0 || 267 strncmp(buf, "Apparently-To:", 3)) 268 break; 269 cont = 1; 270 goto findme; 271 case 'D': 272 if ((tflag & DELIVERED_TO) == 0 || 273 strncmp(buf, "Delivered-To:", 3)) 274 break; 275 cont = 1; 276 goto findme; 277 default: 278 if (!isspace((unsigned char)*buf) || !cont || tome) { 279 cont = 0; 280 break; 281 } 282 findme: for (cur = names; !tome && cur; cur = cur->next) 283 tome += nsearch(cur->name, buf); 284 } 285 if (!tome) 286 exit(0); 287 if (!*from) { 288 syslog(LOG_ERR, "vacation: no initial \"From\" line."); 289 exit(1); 290 } 291 } 292 293 /* 294 * nsearch -- 295 * do a nice, slow, search of a string for a substring. 296 */ 297 int 298 nsearch(const char *name, const char *str) 299 { 300 size_t len; 301 302 for (len = strlen(name); *str; ++str) 303 if (!strncasecmp(name, str, len)) 304 return(1); 305 return(0); 306 } 307 308 /* 309 * junkmail -- 310 * read the header and return if automagic/junk/bulk/list mail 311 */ 312 int 313 junkmail(void) 314 { 315 static struct ignore { 316 char *name; 317 int len; 318 } ignore[] = { 319 { "-request", 8 }, 320 { "postmaster", 10 }, 321 { "uucp", 4 }, 322 { "mailer-daemon", 13 }, 323 { "mailer", 6 }, 324 { "-relay", 6 }, 325 {NULL, 0 } 326 }; 327 struct ignore *cur; 328 int len; 329 char *p; 330 331 /* 332 * This is mildly amusing, and I'm not positive it's right; trying 333 * to find the "real" name of the sender, assuming that addresses 334 * will be some variant of: 335 * 336 * From site!site!SENDER%site.domain%site.domain (at) site.domain 337 */ 338 if (!(p = strchr(from, '%'))) 339 if (!(p = strchr(from, '@'))) { 340 if ((p = strrchr(from, '!'))) 341 ++p; 342 else 343 p = from; 344 for (; *p; ++p); 345 } 346 len = p - from; 347 for (cur = ignore; cur->name; ++cur) 348 if (len >= cur->len && 349 !strncasecmp(cur->name, p - cur->len, cur->len)) 350 return(1); 351 return(0); 352 } 353 354 #define VIT "__VACATION__INTERVAL__TIMER__" 355 356 /* 357 * recent -- 358 * find out if user has gotten a vacation message recently. 359 * use memmove for machines with alignment restrictions 360 */ 361 int 362 recent(void) 363 { 364 DBT key, data; 365 time_t then, next; 366 367 /* get interval time */ 368 key.data = VIT; 369 key.size = sizeof(VIT); 370 if ((db->get)(db, &key, &data, 0)) 371 next = SECSPERDAY * DAYSPERWEEK; 372 else 373 memmove(&next, data.data, sizeof(next)); 374 375 /* get record for this address */ 376 key.data = from; 377 key.size = strlen(from); 378 if (!(db->get)(db, &key, &data, 0)) { 379 memmove(&then, data.data, sizeof(then)); 380 if (next == (time_t)LONG_MAX || /* XXX */ 381 then + next > time(NULL)) 382 return(1); 383 } 384 return(0); 385 } 386 387 /* 388 * setinterval -- 389 * store the reply interval 390 */ 391 void 392 setinterval(time_t interval) 393 { 394 DBT key, data; 395 396 key.data = VIT; 397 key.size = sizeof(VIT); 398 data.data = &interval; 399 data.size = sizeof(interval); 400 (void)(db->put)(db, &key, &data, 0); 401 } 402 403 /* 404 * setreply -- 405 * store that this user knows about the vacation. 406 */ 407 void 408 setreply(void) 409 { 410 DBT key, data; 411 time_t now; 412 413 key.data = from; 414 key.size = strlen(from); 415 (void)time(&now); 416 data.data = &now; 417 data.size = sizeof(now); 418 (void)(db->put)(db, &key, &data, 0); 419 } 420 421 /* 422 * sendmessage -- 423 * exec sendmail to send the vacation file to sender 424 */ 425 void 426 sendmessage(const char *myname) 427 { 428 FILE *mfp, *sfp; 429 int i; 430 int pvect[2]; 431 char buf[MAXLINE]; 432 433 mfp = fopen(VMSG, "r"); 434 if (mfp == NULL) { 435 syslog(LOG_ERR, "vacation: no ~%s/%s file.", myname, VMSG); 436 exit(1); 437 } 438 if (pipe(pvect) < 0) { 439 syslog(LOG_ERR, "vacation: pipe: %m"); 440 exit(1); 441 } 442 i = vfork(); 443 if (i < 0) { 444 syslog(LOG_ERR, "vacation: fork: %m"); 445 exit(1); 446 } 447 if (i == 0) { 448 dup2(pvect[0], 0); 449 close(pvect[0]); 450 close(pvect[1]); 451 close(fileno(mfp)); 452 execl(_PATH_SENDMAIL, "sendmail", "-f", myname, "--", from, 453 NULL); 454 syslog(LOG_ERR, "vacation: can't exec %s: %m", 455 _PATH_SENDMAIL); 456 _exit(1); 457 } 458 close(pvect[0]); 459 sfp = fdopen(pvect[1], "w"); 460 fprintf(sfp, "To: %s\n", from); 461 while (fgets(buf, sizeof buf, mfp)) 462 fputs(buf, sfp); 463 fclose(mfp); 464 fclose(sfp); 465 } 466 467 void 468 usage(void) 469 { 470 471 syslog(LOG_ERR, "uid %u: usage: %s [-i] [-a alias] [-t A|D] login", 472 getuid(), getprogname()); 473 exit(1); 474 } 475
Indexes created Thu Oct 02 14:10:14 GMT 2025