vacation.c revision 1.26
1 /* $NetBSD: vacation.c,v 1.26 2004/04/03 23:57:32 christos 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 1.26 2004/04/03 23:57:32 christos 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 static int fflag = 0; 95 #define FROM_FROM 1 96 #define RETURN_PATH_FROM 2 97 #define SENDER_FROM 4 98 99 int main(int, char **); 100 int junkmail(void); 101 int nsearch(const char *, const char *); 102 void readheaders(void); 103 int recent(void); 104 void getfrom(char *); 105 void sendmessage(const char *); 106 void setinterval(time_t); 107 void setreply(void); 108 void usage(void); 109 110 int 111 main(int argc, char **argv) 112 { 113 struct passwd *pw; 114 alias_t *cur; 115 time_t interval; 116 int ch, iflag; 117 char *p; 118 119 opterr = iflag = 0; 120 interval = -1; 121 openlog(getprogname(), 0, LOG_USER); 122 while ((ch = getopt(argc, argv, "a:f:Iir:t:")) != -1) 123 switch((char)ch) { 124 case 'a': /* alias */ 125 if (!(cur = (alias_t *)malloc((size_t)sizeof(alias_t)))) 126 break; 127 cur->name = optarg; 128 cur->next = names; 129 names = cur; 130 break; 131 case 'f': 132 for (p = optarg; *p; p++) 133 switch (*p) { 134 case 'F': 135 fflag |= FROM_FROM; 136 break; 137 case 'R': 138 fflag |= RETURN_PATH_FROM; 139 break; 140 case 'S': 141 fflag |= SENDER_FROM; 142 break; 143 default: 144 errx(1, "Unknown -f option `%c'", *p); 145 } 146 break; 147 case 'I': /* backward compatible */ 148 case 'i': /* init the database */ 149 iflag = 1; 150 break; 151 case 'r': 152 if (isdigit((unsigned char)*optarg)) { 153 interval = atol(optarg) * SECSPERDAY; 154 if (interval < 0) 155 usage(); 156 } 157 else 158 interval = (time_t)LONG_MAX; /* XXX */ 159 break; 160 case 't': 161 for (p = optarg; *p; p++) 162 switch (*p) { 163 case 'A': 164 tflag |= APPARENTLY_TO; 165 break; 166 case 'D': 167 tflag |= DELIVERED_TO; 168 break; 169 default: 170 errx(1, "Unknown -t option `%c'", *p); 171 } 172 break; 173 case '?': 174 default: 175 usage(); 176 } 177 argc -= optind; 178 argv += optind; 179 180 if (argc != 1) { 181 if (!iflag) 182 usage(); 183 if (!(pw = getpwuid(getuid()))) { 184 syslog(LOG_ERR, 185 "vacation: no such user uid %u.", getuid()); 186 exit(1); 187 } 188 } 189 else if (!(pw = getpwnam(*argv))) { 190 syslog(LOG_ERR, "vacation: no such user %s.", *argv); 191 exit(1); 192 } 193 if (chdir(pw->pw_dir)) { 194 syslog(LOG_ERR, 195 "vacation: no such directory %s.", pw->pw_dir); 196 exit(1); 197 } 198 199 db = dbopen(VDB, O_CREAT|O_RDWR | (iflag ? O_TRUNC : 0), 200 S_IRUSR|S_IWUSR, DB_HASH, NULL); 201 if (!db) { 202 syslog(LOG_ERR, "vacation: %s: %m", VDB); 203 exit(1); 204 } 205 206 if (interval != -1) 207 setinterval(interval); 208 209 if (iflag) { 210 (void)(db->close)(db); 211 exit(0); 212 } 213 214 if (!(cur = malloc((size_t)sizeof(alias_t)))) 215 exit(1); 216 cur->name = pw->pw_name; 217 cur->next = names; 218 names = cur; 219 220 readheaders(); 221 if (!recent()) { 222 setreply(); 223 (void)(db->close)(db); 224 sendmessage(pw->pw_name); 225 } 226 else 227 (void)(db->close)(db); 228 exit(0); 229 /* NOTREACHED */ 230 } 231 232 /* 233 * readheaders -- 234 * read mail headers 235 */ 236 void 237 readheaders(void) 238 { 239 alias_t *cur; 240 char *p; 241 int tome, cont; 242 char buf[MAXLINE]; 243 244 cont = tome = 0; 245 while (fgets(buf, sizeof(buf), stdin) && *buf != '\n') 246 switch(*buf) { 247 case 'F': /* "From " or "From:" */ 248 cont = 0; 249 if (!strncmp(buf, "From ", 5)) 250 getfrom(buf + 5); 251 if ((fflag & FROM_FROM) != 0 && 252 strncmp(buf, "From:", 5) == 0) 253 getfrom(buf + 5); 254 break; 255 case 'P': /* "Precedence:" */ 256 cont = 0; 257 if (strncasecmp(buf, "Precedence", 10) || 258 (buf[10] != ':' && buf[10] != ' ' && 259 buf[10] != '\t')) 260 break; 261 if (!(p = strchr(buf, ':'))) 262 break; 263 while (*++p && isspace((unsigned char)*p)) 264 continue; 265 if (!*p) 266 break; 267 if (!strncasecmp(p, "junk", 4) || 268 !strncasecmp(p, "bulk", 4) || 269 !strncasecmp(p, "list", 4)) 270 exit(0); 271 break; 272 case 'C': /* "Cc:" */ 273 if (strncmp(buf, "Cc:", 3)) 274 break; 275 cont = 1; 276 goto findme; 277 case 'T': /* "To:" */ 278 if (strncmp(buf, "To:", 3)) 279 break; 280 cont = 1; 281 goto findme; 282 case 'A': /* "Apparently-To:" */ 283 if ((tflag & APPARENTLY_TO) == 0 || 284 strncmp(buf, "Apparently-To:", 14)) 285 break; 286 cont = 1; 287 goto findme; 288 case 'D': /* "Delivered-To:" */ 289 if ((tflag & DELIVERED_TO) == 0 || 290 strncmp(buf, "Delivered-To:", 13)) 291 break; 292 cont = 1; 293 goto findme; 294 case 'R': /* "Return-Path:" */ 295 cont = 0; 296 if ((fflag & RETURN_PATH_FROM) != 0 && 297 strncmp(buf, "Return-Path:", 12) == 0) 298 getfrom(buf + 12); 299 break; 300 case 'S': /* "Sender:" */ 301 cont = 0; 302 if ((fflag & SENDER_FROM) != 0 && 303 strncmp(buf, "Sender:", 7) == 0) 304 getfrom(buf + 7); 305 break; 306 default: 307 if (!isspace((unsigned char)*buf) || !cont || tome) { 308 cont = 0; 309 break; 310 } 311 findme: for (cur = names; !tome && cur; cur = cur->next) 312 tome += nsearch(cur->name, buf); 313 } 314 if (!tome) 315 exit(0); 316 if (!*from) { 317 syslog(LOG_ERR, "vacation: no initial \"From\" line."); 318 exit(1); 319 } 320 } 321 322 /* 323 * nsearch -- 324 * do a nice, slow, search of a string for a substring. 325 */ 326 int 327 nsearch(const char *name, const char *str) 328 { 329 size_t len; 330 331 for (len = strlen(name); *str; ++str) 332 if (!strncasecmp(name, str, len)) 333 return(1); 334 return(0); 335 } 336 337 /* 338 * getfrom -- 339 * return the first string in the buffer, stripping leading and trailing 340 * blanks and <>. 341 */ 342 void 343 getfrom(char *buf) 344 { 345 char *s, *p; 346 347 for (s = buf; *s && isspace((unsigned char)*s); s++) 348 continue; 349 if (*s == '<') 350 *s++; 351 for (p = s; *p && !isspace((unsigned char)*p); p++) 352 continue; 353 if (*--p == '>') 354 *p = '\0'; 355 else 356 *p = '\0'; 357 (void)strlcpy(from, s, sizeof(from)); 358 if (junkmail()) 359 exit(0); 360 } 361 362 /* 363 * junkmail -- 364 * read the header and return if automagic/junk/bulk/list mail 365 */ 366 int 367 junkmail(void) 368 { 369 static struct ignore { 370 char *name; 371 int len; 372 } ignore[] = { 373 { "-request", 8 }, 374 { "postmaster", 10 }, 375 { "uucp", 4 }, 376 { "mailer-daemon", 13 }, 377 { "mailer", 6 }, 378 { "-relay", 6 }, 379 {NULL, 0 } 380 }; 381 struct ignore *cur; 382 int len; 383 char *p; 384 385 /* 386 * This is mildly amusing, and I'm not positive it's right; trying 387 * to find the "real" name of the sender, assuming that addresses 388 * will be some variant of: 389 * 390 * From site!site!SENDER%site.domain%site.domain (at) site.domain 391 */ 392 if (!(p = strchr(from, '%'))) 393 if (!(p = strchr(from, '@'))) { 394 if ((p = strrchr(from, '!'))) 395 ++p; 396 else 397 p = from; 398 for (; *p; ++p); 399 } 400 len = p - from; 401 for (cur = ignore; cur->name; ++cur) 402 if (len >= cur->len && 403 !strncasecmp(cur->name, p - cur->len, cur->len)) 404 return(1); 405 return(0); 406 } 407 408 #define VIT "__VACATION__INTERVAL__TIMER__" 409 410 /* 411 * recent -- 412 * find out if user has gotten a vacation message recently. 413 * use memmove for machines with alignment restrictions 414 */ 415 int 416 recent(void) 417 { 418 DBT key, data; 419 time_t then, next; 420 421 /* get interval time */ 422 key.data = VIT; 423 key.size = sizeof(VIT); 424 if ((db->get)(db, &key, &data, 0)) 425 next = SECSPERDAY * DAYSPERWEEK; 426 else 427 memmove(&next, data.data, sizeof(next)); 428 429 /* get record for this address */ 430 key.data = from; 431 key.size = strlen(from); 432 if (!(db->get)(db, &key, &data, 0)) { 433 memmove(&then, data.data, sizeof(then)); 434 if (next == (time_t)LONG_MAX || /* XXX */ 435 then + next > time(NULL)) 436 return(1); 437 } 438 return(0); 439 } 440 441 /* 442 * setinterval -- 443 * store the reply interval 444 */ 445 void 446 setinterval(time_t interval) 447 { 448 DBT key, data; 449 450 key.data = VIT; 451 key.size = sizeof(VIT); 452 data.data = &interval; 453 data.size = sizeof(interval); 454 (void)(db->put)(db, &key, &data, 0); 455 } 456 457 /* 458 * setreply -- 459 * store that this user knows about the vacation. 460 */ 461 void 462 setreply(void) 463 { 464 DBT key, data; 465 time_t now; 466 467 key.data = from; 468 key.size = strlen(from); 469 (void)time(&now); 470 data.data = &now; 471 data.size = sizeof(now); 472 (void)(db->put)(db, &key, &data, 0); 473 } 474 475 /* 476 * sendmessage -- 477 * exec sendmail to send the vacation file to sender 478 */ 479 void 480 sendmessage(const char *myname) 481 { 482 FILE *mfp, *sfp; 483 int i; 484 int pvect[2]; 485 char buf[MAXLINE]; 486 487 mfp = fopen(VMSG, "r"); 488 if (mfp == NULL) { 489 syslog(LOG_ERR, "vacation: no ~%s/%s file.", myname, VMSG); 490 exit(1); 491 } 492 if (pipe(pvect) < 0) { 493 syslog(LOG_ERR, "vacation: pipe: %m"); 494 exit(1); 495 } 496 i = vfork(); 497 if (i < 0) { 498 syslog(LOG_ERR, "vacation: fork: %m"); 499 exit(1); 500 } 501 if (i == 0) { 502 dup2(pvect[0], 0); 503 close(pvect[0]); 504 close(pvect[1]); 505 close(fileno(mfp)); 506 execl(_PATH_SENDMAIL, "sendmail", "-f", myname, "--", from, 507 NULL); 508 syslog(LOG_ERR, "vacation: can't exec %s: %m", 509 _PATH_SENDMAIL); 510 _exit(1); 511 } 512 close(pvect[0]); 513 sfp = fdopen(pvect[1], "w"); 514 fprintf(sfp, "To: %s\n", from); 515 while (fgets(buf, sizeof buf, mfp)) 516 fputs(buf, sfp); 517 fclose(mfp); 518 fclose(sfp); 519 } 520 521 void 522 usage(void) 523 { 524 525 syslog(LOG_ERR, "uid %u: usage: %s [-i] [-a alias] [-t A|D] login", 526 getuid(), getprogname()); 527 exit(1); 528 } 529
Indexes created Thu Oct 02 14:10:14 GMT 2025