1 /*- 2 * Copyright (c) 1990, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #ifndef lint 9 static char copyright[] = 10 "@(#) Copyright (c) 1990, 1993, 1994\n\ 11 The Regents of the University of California. All rights reserved.\n"; 12 #endif /* not lint */ 13 14 #ifndef lint 15 static char sccsid[] = "@(#)mail.local.c 8.14 (Berkeley) 01/18/95"; 16 #endif /* not lint */ 17 18 #include <sys/param.h> 19 #include <sys/stat.h> 20 #include <sys/socket.h> 21 22 #include <netinet/in.h> 23 24 #include <errno.h> 25 #include <fcntl.h> 26 #include <netdb.h> 27 #include <pwd.h> 28 #include <stdio.h> 29 #include <stdlib.h> 30 #include <string.h> 31 #include <sysexits.h> 32 #include <syslog.h> 33 #include <time.h> 34 #include <unistd.h> 35 36 #if __STDC__ 37 #include <stdarg.h> 38 #else 39 #include <varargs.h> 40 #endif 41 42 #ifndef LOCK_EX 43 # include <sys/file.h> 44 #endif 45 46 #ifdef BSD4_4 47 # include "pathnames.h" 48 #endif 49 50 #ifndef __P 51 # ifdef __STDC__ 52 # define __P(protos) protos 53 # else 54 # define __P(protos) () 55 # define const 56 # endif 57 #endif 58 #ifndef __dead 59 # if defined(__GNUC__) && (__GNUC__ < 2 || __GNUC_MINOR__ < 5) && !defined(__STRICT_ANSI__) 60 # define __dead __volatile 61 # else 62 # define __dead 63 # endif 64 #endif 65 66 #ifndef BSD4_4 67 # define _BSD_VA_LIST_ va_list 68 extern char *strerror __P((int)); 69 #endif 70 71 #ifndef _PATH_LOCTMP 72 # define _PATH_LOCTMP "/tmp/local.XXXXXX" 73 #endif 74 #ifndef _PATH_MAILDIR 75 # define _PATH_MAILDIR "/var/spool/mail" 76 #endif 77 78 #ifndef S_ISREG 79 # define S_ISREG(mode) (((mode) & _S_IFMT) == S_IFREG) 80 #endif 81 82 int eval = EX_OK; /* sysexits.h error value. */ 83 84 void deliver __P((int, char *)); 85 void e_to_sys __P((int)); 86 __dead void err __P((const char *, ...)); 87 void notifybiff __P((char *)); 88 int store __P((char *)); 89 void usage __P((void)); 90 void vwarn __P((const char *, _BSD_VA_LIST_)); 91 void warn __P((const char *, ...)); 92 93 int 94 main(argc, argv) 95 int argc; 96 char *argv[]; 97 { 98 struct passwd *pw; 99 int ch, fd; 100 uid_t uid; 101 char *from; 102 extern char *optarg; 103 extern int optind; 104 105 #ifdef LOG_MAIL 106 openlog("mail.local", 0, LOG_MAIL); 107 #else 108 openlog("mail.local", 0); 109 #endif 110 111 from = NULL; 112 while ((ch = getopt(argc, argv, "df:r:")) != EOF) 113 switch(ch) { 114 case 'd': /* Backward compatible. */ 115 break; 116 case 'f': 117 case 'r': /* Backward compatible. */ 118 if (from != NULL) { 119 warn("multiple -f options"); 120 usage(); 121 } 122 from = optarg; 123 break; 124 case '?': 125 default: 126 usage(); 127 } 128 argc -= optind; 129 argv += optind; 130 131 if (!*argv) 132 usage(); 133 134 /* 135 * If from not specified, use the name from getlogin() if the 136 * uid matches, otherwise, use the name from the password file 137 * corresponding to the uid. 138 */ 139 uid = getuid(); 140 if (!from && (!(from = getlogin()) || 141 !(pw = getpwnam(from)) || pw->pw_uid != uid)) 142 from = (pw = getpwuid(uid)) ? pw->pw_name : "???"; 143 144 /* 145 * There is no way to distinguish the error status of one delivery 146 * from the rest of the deliveries. So, if we failed hard on one 147 * or more deliveries, but had no failures on any of the others, we 148 * return a hard failure. If we failed temporarily on one or more 149 * deliveries, we return a temporary failure regardless of the other 150 * failures. This results in the delivery being reattempted later 151 * at the expense of repeated failures and multiple deliveries. 152 */ 153 for (fd = store(from); *argv; ++argv) 154 deliver(fd, *argv); 155 exit(eval); 156 } 157 158 int 159 store(from) 160 char *from; 161 { 162 FILE *fp; 163 time_t tval; 164 int fd, eline; 165 char line[2048]; 166 char tmpbuf[sizeof _PATH_LOCTMP + 1]; 167 168 strcpy(tmpbuf, _PATH_LOCTMP); 169 if ((fd = mkstemp(tmpbuf)) == -1 || (fp = fdopen(fd, "w+")) == NULL) { 170 e_to_sys(errno); 171 err("unable to open temporary file"); 172 } 173 (void)unlink(tmpbuf); 174 175 (void)time(&tval); 176 (void)fprintf(fp, "From %s %s", from, ctime(&tval)); 177 178 line[0] = '\0'; 179 for (eline = 1; fgets(line, sizeof(line), stdin);) { 180 if (line[0] == '\n') 181 eline = 1; 182 else { 183 if (eline && line[0] == 'F' && 184 !memcmp(line, "From ", 5)) 185 (void)putc('>', fp); 186 eline = 0; 187 } 188 (void)fprintf(fp, "%s", line); 189 if (ferror(fp)) { 190 e_to_sys(errno); 191 err("temporary file write error"); 192 } 193 } 194 195 /* If message not newline terminated, need an extra. */ 196 if (!strchr(line, '\n')) 197 (void)putc('\n', fp); 198 /* Output a newline; note, empty messages are allowed. */ 199 (void)putc('\n', fp); 200 201 if (fflush(fp) == EOF || ferror(fp)) { 202 e_to_sys(errno); 203 err("temporary file write error"); 204 } 205 return (fd); 206 } 207 208 void 209 deliver(fd, name) 210 int fd; 211 char *name; 212 { 213 struct stat fsb, sb; 214 struct passwd *pw; 215 int mbfd, nr, nw, off; 216 char biffmsg[100], buf[8*1024], path[MAXPATHLEN]; 217 off_t curoff; 218 219 /* 220 * Disallow delivery to unknown names -- special mailboxes can be 221 * handled in the sendmail aliases file. 222 */ 223 if (!(pw = getpwnam(name))) { 224 if (eval != EX_TEMPFAIL) 225 eval = EX_UNAVAILABLE; 226 warn("unknown name: %s", name); 227 return; 228 } 229 230 (void)snprintf(path, sizeof(path), "%s/%s", _PATH_MAILDIR, name); 231 232 /* 233 * If the mailbox is linked or a symlink, fail. There's an obvious 234 * race here, that the file was replaced with a symbolic link after 235 * the lstat returned, but before the open. We attempt to detect 236 * this by comparing the original stat information and information 237 * returned by an fstat of the file descriptor returned by the open. 238 * 239 * NB: this is a symptom of a larger problem, that the mail spooling 240 * directory is writeable by the wrong users. If that directory is 241 * writeable, system security is compromised for other reasons, and 242 * it cannot be fixed here. 243 * 244 * If we created the mailbox, set the owner/group. If that fails, 245 * just return. Another process may have already opened it, so we 246 * can't unlink it. Historically, binmail set the owner/group at 247 * each mail delivery. We no longer do this, assuming that if the 248 * ownership or permissions were changed there was a reason. 249 * 250 * XXX 251 * open(2) should support flock'ing the file. 252 */ 253 tryagain: 254 lockmbox(path); 255 if (lstat(path, &sb)) { 256 mbfd = open(path, 257 O_APPEND|O_CREAT|O_EXCL|O_WRONLY, S_IRUSR|S_IWUSR); 258 if (mbfd == -1) { 259 if (errno == EEXIST) 260 goto tryagain; 261 } else if (fchown(mbfd, pw->pw_uid, pw->pw_gid)) { 262 e_to_sys(errno); 263 warn("chown %u.%u: %s", pw->pw_uid, pw->pw_gid, name); 264 unlockmbox(); 265 return; 266 } 267 } else if (sb.st_nlink != 1 || !S_ISREG(sb.st_mode)) { 268 e_to_sys(errno); 269 warn("%s: irregular file", path); 270 unlockmbox(); 271 return; 272 } else if (sb.st_uid != pw->pw_uid) { 273 warn("%s: wrong ownership (%d)", path, sb.st_uid); 274 unlockmbox(); 275 return; 276 } else { 277 mbfd = open(path, O_APPEND|O_WRONLY, 0); 278 if (mbfd != -1 && 279 (fstat(mbfd, &fsb) || fsb.st_nlink != 1 || 280 !S_ISREG(fsb.st_mode) || sb.st_dev != fsb.st_dev || 281 sb.st_ino != fsb.st_ino || sb.st_uid != fsb.st_uid)) { 282 warn("%s: file changed after open", path); 283 (void)close(mbfd); 284 unlockmbox(); 285 return; 286 } 287 } 288 289 if (mbfd == -1) { 290 e_to_sys(errno); 291 warn("%s: %s", path, strerror(errno)); 292 unlockmbox(); 293 return; 294 } 295 296 /* Wait until we can get a lock on the file. */ 297 if (flock(mbfd, LOCK_EX)) { 298 e_to_sys(errno); 299 warn("%s: %s", path, strerror(errno)); 300 unlockmbox(); 301 goto err1; 302 } 303 304 /* Get the starting offset of the new message for biff. */ 305 curoff = lseek(mbfd, (off_t)0, SEEK_END); 306 (void)snprintf(biffmsg, sizeof(biffmsg), 307 sizeof curoff > sizeof(long) ? "%s@%qd\n" : "%s@%ld\n", 308 name, curoff); 309 310 /* Copy the message into the file. */ 311 if (lseek(fd, (off_t)0, SEEK_SET) == (off_t)-1) { 312 e_to_sys(errno); 313 warn("temporary file: %s", strerror(errno)); 314 goto err1; 315 } 316 while ((nr = read(fd, buf, sizeof(buf))) > 0) 317 for (off = 0; off < nr; nr -= nw, off += nw) 318 if ((nw = write(mbfd, buf + off, nr)) < 0) { 319 e_to_sys(errno); 320 warn("%s: %s", path, strerror(errno)); 321 goto err2;; 322 } 323 if (nr < 0) { 324 e_to_sys(errno); 325 warn("temporary file: %s", strerror(errno)); 326 goto err2;; 327 } 328 329 /* Flush to disk, don't wait for update. */ 330 if (fsync(mbfd)) { 331 e_to_sys(errno); 332 warn("%s: %s", path, strerror(errno)); 333 err2: (void)ftruncate(mbfd, curoff); 334 err1: (void)close(mbfd); 335 unlockmbox(); 336 return; 337 } 338 339 /* Close and check -- NFS doesn't write until the close. */ 340 if (close(mbfd)) { 341 e_to_sys(errno); 342 warn("%s: %s", path, strerror(errno)); 343 unlockmbox(); 344 return; 345 } 346 347 unlockmbox(); 348 notifybiff(biffmsg); 349 } 350 351 /* 352 * user.lock files are necessary for compatibility with other 353 * systems, e.g., when the mail spool file is NFS exported. 354 * Alas, mailbox locking is more than just a local matter. 355 * EPA 11/94. 356 */ 357 358 char lockname[50]; 359 int locked = 0; 360 361 lockmbox(path) 362 char *path; 363 { 364 int statfailed = 0; 365 366 if (locked) 367 return; 368 sprintf(lockname, "%s.lock", path); 369 for (;; sleep(5)) { 370 int fd; 371 struct stat st; 372 time_t now; 373 374 fd = open(lockname, O_WRONLY|O_EXCL|O_CREAT, 0); 375 if (fd >= 0) { 376 locked = 1; 377 close(fd); 378 return; 379 } 380 if (stat(lockname, &st) < 0) { 381 if (statfailed++ > 5) 382 return; 383 continue; 384 } 385 statfailed = 0; 386 time(&now); 387 if (now < st.st_ctime + 300) 388 continue; 389 unlink(lockname); 390 } 391 } 392 393 unlockmbox() 394 { 395 if (!locked) 396 return; 397 unlink(lockname); 398 locked = 0; 399 } 400 401 void 402 notifybiff(msg) 403 char *msg; 404 { 405 static struct sockaddr_in addr; 406 static int f = -1; 407 struct hostent *hp; 408 struct servent *sp; 409 int len; 410 411 if (!addr.sin_family) { 412 /* Be silent if biff service not available. */ 413 if (!(sp = getservbyname("biff", "udp"))) 414 return; 415 if (!(hp = gethostbyname("localhost"))) { 416 warn("localhost: %s", strerror(errno)); 417 return; 418 } 419 addr.sin_family = hp->h_addrtype; 420 memcpy(&addr.sin_addr, hp->h_addr, hp->h_length); 421 addr.sin_port = sp->s_port; 422 } 423 if (f < 0 && (f = socket(AF_INET, SOCK_DGRAM, 0)) == -1) { 424 warn("socket: %s", strerror(errno)); 425 return; 426 } 427 len = strlen(msg) + 1; 428 if (sendto(f, msg, len, 0, (struct sockaddr *)&addr, sizeof(addr)) 429 != len) 430 warn("sendto biff: %s", strerror(errno)); 431 } 432 433 void 434 usage() 435 { 436 eval = EX_USAGE; 437 err("usage: mail.local [-f from] user ..."); 438 } 439 440 #if __STDC__ 441 void 442 err(const char *fmt, ...) 443 #else 444 void 445 err(fmt, va_alist) 446 const char *fmt; 447 va_dcl 448 #endif 449 { 450 va_list ap; 451 452 #if __STDC__ 453 va_start(ap, fmt); 454 #else 455 va_start(ap); 456 #endif 457 vwarn(fmt, ap); 458 va_end(ap); 459 460 exit(eval); 461 } 462 463 void 464 #if __STDC__ 465 warn(const char *fmt, ...) 466 #else 467 warn(fmt, va_alist) 468 const char *fmt; 469 va_dcl 470 #endif 471 { 472 va_list ap; 473 474 #if __STDC__ 475 va_start(ap, fmt); 476 #else 477 va_start(ap); 478 #endif 479 vwarn(fmt, ap); 480 va_end(ap); 481 } 482 483 void 484 vwarn(fmt, ap) 485 const char *fmt; 486 _BSD_VA_LIST_ ap; 487 { 488 /* 489 * Log the message to stderr. 490 * 491 * Don't use LOG_PERROR as an openlog() flag to do this, 492 * it's not portable enough. 493 */ 494 if (eval != EX_USAGE) 495 (void)fprintf(stderr, "mail.local: "); 496 (void)vfprintf(stderr, fmt, ap); 497 (void)fprintf(stderr, "\n"); 498 499 #ifndef ultrix 500 /* Log the message to syslog. */ 501 vsyslog(LOG_ERR, fmt, ap); 502 #else 503 { 504 char fmtbuf[10240]; 505 506 (void) sprintf(fmtbuf, fmt, ap); 507 syslog(LOG_ERR, "%s", fmtbuf); 508 } 509 #endif 510 } 511 512 /* 513 * e_to_sys -- 514 * Guess which errno's are temporary. Gag me. 515 */ 516 void 517 e_to_sys(num) 518 int num; 519 { 520 /* Temporary failures override hard errors. */ 521 if (eval == EX_TEMPFAIL) 522 return; 523 524 switch(num) { /* Hopefully temporary errors. */ 525 #ifdef EAGAIN 526 case EAGAIN: /* Resource temporarily unavailable */ 527 #endif 528 #ifdef EDQUOT 529 case EDQUOT: /* Disc quota exceeded */ 530 #endif 531 #ifdef EBUSY 532 case EBUSY: /* Device busy */ 533 #endif 534 #ifdef EPROCLIM 535 case EPROCLIM: /* Too many processes */ 536 #endif 537 #ifdef EUSERS 538 case EUSERS: /* Too many users */ 539 #endif 540 #ifdef ECONNABORTED 541 case ECONNABORTED: /* Software caused connection abort */ 542 #endif 543 #ifdef ECONNREFUSED 544 case ECONNREFUSED: /* Connection refused */ 545 #endif 546 #ifdef ECONNRESET 547 case ECONNRESET: /* Connection reset by peer */ 548 #endif 549 #ifdef EDEADLK 550 case EDEADLK: /* Resource deadlock avoided */ 551 #endif 552 #ifdef EFBIG 553 case EFBIG: /* File too large */ 554 #endif 555 #ifdef EHOSTDOWN 556 case EHOSTDOWN: /* Host is down */ 557 #endif 558 #ifdef EHOSTUNREACH 559 case EHOSTUNREACH: /* No route to host */ 560 #endif 561 #ifdef EMFILE 562 case EMFILE: /* Too many open files */ 563 #endif 564 #ifdef ENETDOWN 565 case ENETDOWN: /* Network is down */ 566 #endif 567 #ifdef ENETRESET 568 case ENETRESET: /* Network dropped connection on reset */ 569 #endif 570 #ifdef ENETUNREACH 571 case ENETUNREACH: /* Network is unreachable */ 572 #endif 573 #ifdef ENFILE 574 case ENFILE: /* Too many open files in system */ 575 #endif 576 #ifdef ENOBUFS 577 case ENOBUFS: /* No buffer space available */ 578 #endif 579 #ifdef ENOMEM 580 case ENOMEM: /* Cannot allocate memory */ 581 #endif 582 #ifdef ENOSPC 583 case ENOSPC: /* No space left on device */ 584 #endif 585 #ifdef EROFS 586 case EROFS: /* Read-only file system */ 587 #endif 588 #ifdef ESTALE 589 case ESTALE: /* Stale NFS file handle */ 590 #endif 591 #ifdef ETIMEDOUT 592 case ETIMEDOUT: /* Connection timed out */ 593 #endif 594 #if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN && EWOULDBLOCK != EDEADLK 595 case EWOULDBLOCK: /* Operation would block. */ 596 #endif 597 eval = EX_TEMPFAIL; 598 break; 599 default: 600 eval = EX_UNAVAILABLE; 601 break; 602 } 603 } 604 605 #ifndef BSD4_4 606 607 char * 608 strerror(eno) 609 int eno; 610 { 611 extern int sys_nerr; 612 extern char *sys_errlist[]; 613 static char ebuf[60]; 614 615 if (eno >= 0 && eno <= sys_nerr) 616 return sys_errlist[eno]; 617 (void) sprintf(ebuf, "Error %d", eno); 618 return ebuf; 619 } 620 621 #if __STDC__ 622 snprintf(char *buf, int bufsiz, const char *fmt, ...) 623 #else 624 snprintf(buf, bufsiz, fmt, va_alist) 625 char *buf; 626 int bufsiz; 627 const char *fmt; 628 va_dcl 629 #endif 630 { 631 va_list ap; 632 633 #if __STDC__ 634 va_start(ap, fmt); 635 #else 636 va_start(ap); 637 #endif 638 vsprintf(buf, fmt, ap); 639 va_end(ap); 640 } 641 642 #endif 643 644 #ifdef ultrix 645 646 /* 647 * Copyright (c) 1987, 1993 648 * The Regents of the University of California. All rights reserved. 649 * 650 * Redistribution and use in source and binary forms, with or without 651 * modification, are permitted provided that the following conditions 652 * are met: 653 * 1. Redistributions of source code must retain the above copyright 654 * notice, this list of conditions and the following disclaimer. 655 * 2. Redistributions in binary form must reproduce the above copyright 656 * notice, this list of conditions and the following disclaimer in the 657 * documentation and/or other materials provided with the distribution. 658 * 3. All advertising materials mentioning features or use of this software 659 * must display the following acknowledgement: 660 * This product includes software developed by the University of 661 * California, Berkeley and its contributors. 662 * 4. Neither the name of the University nor the names of its contributors 663 * may be used to endorse or promote products derived from this software 664 * without specific prior written permission. 665 * 666 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 667 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 668 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 669 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 670 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 671 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 672 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 673 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 674 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 675 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 676 * SUCH DAMAGE. 677 */ 678 679 #if defined(LIBC_SCCS) && !defined(lint) 680 static char sccsid[] = "@(#)mktemp.c 8.1 (Berkeley) 6/4/93"; 681 #endif /* LIBC_SCCS and not lint */ 682 683 #include <sys/types.h> 684 #include <sys/stat.h> 685 #include <fcntl.h> 686 #include <errno.h> 687 #include <stdio.h> 688 #include <ctype.h> 689 690 static int _gettemp(); 691 692 mkstemp(path) 693 char *path; 694 { 695 int fd; 696 697 return (_gettemp(path, &fd) ? fd : -1); 698 } 699 700 /* 701 char * 702 mktemp(path) 703 char *path; 704 { 705 return(_gettemp(path, (int *)NULL) ? path : (char *)NULL); 706 } 707 */ 708 709 static 710 _gettemp(path, doopen) 711 char *path; 712 register int *doopen; 713 { 714 extern int errno; 715 register char *start, *trv; 716 struct stat sbuf; 717 u_int pid; 718 719 pid = getpid(); 720 for (trv = path; *trv; ++trv); /* extra X's get set to 0's */ 721 while (*--trv == 'X') { 722 *trv = (pid % 10) + '0'; 723 pid /= 10; 724 } 725 726 /* 727 * check the target directory; if you have six X's and it 728 * doesn't exist this runs for a *very* long time. 729 */ 730 for (start = trv + 1;; --trv) { 731 if (trv <= path) 732 break; 733 if (*trv == '/') { 734 *trv = '\0'; 735 if (stat(path, &sbuf)) 736 return(0); 737 if (!S_ISDIR(sbuf.st_mode)) { 738 errno = ENOTDIR; 739 return(0); 740 } 741 *trv = '/'; 742 break; 743 } 744 } 745 746 for (;;) { 747 if (doopen) { 748 if ((*doopen = 749 open(path, O_CREAT|O_EXCL|O_RDWR, 0600)) >= 0) 750 return(1); 751 if (errno != EEXIST) 752 return(0); 753 } 754 else if (stat(path, &sbuf)) 755 return(errno == ENOENT ? 1 : 0); 756 757 /* tricky little algorithm for backward compatibility */ 758 for (trv = start;;) { 759 if (!*trv) 760 return(0); 761 if (*trv == 'z') 762 *trv++ = 'a'; 763 else { 764 if (isdigit(*trv)) 765 *trv = 'a'; 766 else 767 ++*trv; 768 break; 769 } 770 } 771 } 772 /*NOTREACHED*/ 773 } 774 775 #endif 776