1 /* 2 * Copyright (c) 1983 Eric P. Allman 3 * Copyright (c) 1988 Regents of the University of California. 4 * All rights reserved. 5 * 6 * %sccs.include.redist.c% 7 */ 8 9 #ifndef lint 10 static char sccsid[] = "@(#)savemail.c 6.43 (Berkeley) 05/14/93"; 11 #endif /* not lint */ 12 13 # include <pwd.h> 14 # include "sendmail.h" 15 16 /* 17 ** SAVEMAIL -- Save mail on error 18 ** 19 ** If mailing back errors, mail it back to the originator 20 ** together with an error message; otherwise, just put it in 21 ** dead.letter in the user's home directory (if he exists on 22 ** this machine). 23 ** 24 ** Parameters: 25 ** e -- the envelope containing the message in error. 26 ** 27 ** Returns: 28 ** none 29 ** 30 ** Side Effects: 31 ** Saves the letter, by writing or mailing it back to the 32 ** sender, or by putting it in dead.letter in her home 33 ** directory. 34 */ 35 36 /* defines for state machine */ 37 # define ESM_REPORT 0 /* report to sender's terminal */ 38 # define ESM_MAIL 1 /* mail back to sender */ 39 # define ESM_QUIET 2 /* messages have already been returned */ 40 # define ESM_DEADLETTER 3 /* save in ~/dead.letter */ 41 # define ESM_POSTMASTER 4 /* return to postmaster */ 42 # define ESM_USRTMP 5 /* save in /usr/tmp/dead.letter */ 43 # define ESM_PANIC 6 /* leave the locked queue/transcript files */ 44 # define ESM_DONE 7 /* the message is successfully delivered */ 45 46 47 savemail(e) 48 register ENVELOPE *e; 49 { 50 register struct passwd *pw; 51 register FILE *fp; 52 int state; 53 auto ADDRESS *q = NULL; 54 char buf[MAXLINE+1]; 55 extern struct passwd *getpwnam(); 56 register char *p; 57 extern char *ttypath(); 58 typedef int (*fnptr)(); 59 60 if (tTd(6, 1)) 61 { 62 printf("\nsavemail, errormode = %c, id = %s\n e_from=", 63 e->e_errormode, e->e_id == NULL ? "NONE" : e->e_id); 64 printaddr(&e->e_from, FALSE); 65 } 66 67 if (e->e_id == NULL) 68 { 69 /* can't return a message with no id */ 70 return; 71 } 72 73 e->e_flags &= ~EF_FATALERRS; 74 75 /* 76 ** In the unhappy event we don't know who to return the mail 77 ** to, make someone up. 78 */ 79 80 if (e->e_from.q_paddr == NULL) 81 { 82 e->e_sender = "Postmaster"; 83 if (parseaddr(e->e_sender, &e->e_from, 0, '\0', NULL, e) == NULL) 84 { 85 syserr("553 Cannot parse Postmaster!"); 86 ExitStat = EX_SOFTWARE; 87 finis(); 88 } 89 } 90 e->e_to = NULL; 91 92 /* 93 ** Basic state machine. 94 ** 95 ** This machine runs through the following states: 96 ** 97 ** ESM_QUIET Errors have already been printed iff the 98 ** sender is local. 99 ** ESM_REPORT Report directly to the sender's terminal. 100 ** ESM_MAIL Mail response to the sender. 101 ** ESM_DEADLETTER Save response in ~/dead.letter. 102 ** ESM_POSTMASTER Mail response to the postmaster. 103 ** ESM_PANIC Save response anywhere possible. 104 */ 105 106 /* determine starting state */ 107 switch (e->e_errormode) 108 { 109 case EM_WRITE: 110 state = ESM_REPORT; 111 break; 112 113 case EM_BERKNET: 114 /* mail back, but return o.k. exit status */ 115 ExitStat = EX_OK; 116 117 /* fall through.... */ 118 119 case EM_MAIL: 120 state = ESM_MAIL; 121 break; 122 123 case EM_PRINT: 124 case '\0': 125 state = ESM_QUIET; 126 break; 127 128 case EM_QUIET: 129 /* no need to return anything at all */ 130 return; 131 132 default: 133 syserr("554 savemail: bogus errormode x%x\n", e->e_errormode); 134 state = ESM_MAIL; 135 break; 136 } 137 138 /* if this is already an error response, send to postmaster */ 139 if (bitset(EF_RESPONSE, e->e_flags)) 140 { 141 if (e->e_parent != NULL && 142 bitset(EF_RESPONSE, e->e_parent->e_flags)) 143 { 144 /* got an error sending a response -- can it */ 145 return; 146 } 147 state = ESM_POSTMASTER; 148 } 149 150 while (state != ESM_DONE) 151 { 152 if (tTd(6, 5)) 153 printf(" state %d\n", state); 154 155 switch (state) 156 { 157 case ESM_QUIET: 158 if (e->e_from.q_mailer == LocalMailer) 159 state = ESM_DEADLETTER; 160 else 161 state = ESM_MAIL; 162 break; 163 164 case ESM_REPORT: 165 166 /* 167 ** If the user is still logged in on the same terminal, 168 ** then write the error messages back to hir (sic). 169 */ 170 171 p = ttypath(); 172 if (p == NULL || freopen(p, "w", stdout) == NULL) 173 { 174 state = ESM_MAIL; 175 break; 176 } 177 178 expand("\201n", buf, &buf[sizeof buf - 1], e); 179 printf("\r\nMessage from %s...\r\n", buf); 180 printf("Errors occurred while sending mail.\r\n"); 181 if (e->e_xfp != NULL) 182 { 183 (void) fflush(e->e_xfp); 184 fp = fopen(queuename(e, 'x'), "r"); 185 } 186 else 187 fp = NULL; 188 if (fp == NULL) 189 { 190 syserr("Cannot open %s", queuename(e, 'x')); 191 printf("Transcript of session is unavailable.\r\n"); 192 } 193 else 194 { 195 printf("Transcript follows:\r\n"); 196 while (fgets(buf, sizeof buf, fp) != NULL && 197 !ferror(stdout)) 198 fputs(buf, stdout); 199 (void) xfclose(fp, "savemail transcript", e->e_id); 200 } 201 printf("Original message will be saved in dead.letter.\r\n"); 202 state = ESM_DEADLETTER; 203 break; 204 205 case ESM_MAIL: 206 /* 207 ** If mailing back, do it. 208 ** Throw away all further output. Don't alias, 209 ** since this could cause loops, e.g., if joe 210 ** mails to joe@x, and for some reason the network 211 ** for @x is down, then the response gets sent to 212 ** joe@x, which gives a response, etc. Also force 213 ** the mail to be delivered even if a version of 214 ** it has already been sent to the sender. 215 */ 216 217 if (strcmp(e->e_from.q_paddr, "<>") != 0) 218 (void) sendtolist(e->e_from.q_paddr, 219 (ADDRESS *) NULL, 220 &e->e_errorqueue, e); 221 222 /* deliver a cc: to the postmaster if desired */ 223 if (PostMasterCopy != NULL) 224 { 225 auto ADDRESS *rlist = NULL; 226 227 (void) sendtolist(PostMasterCopy, 228 (ADDRESS *) NULL, 229 &rlist, e); 230 (void) returntosender(e->e_message, 231 rlist, FALSE, e); 232 } 233 q = e->e_errorqueue; 234 if (q == NULL) 235 { 236 /* this is an error-error */ 237 state = ESM_POSTMASTER; 238 break; 239 } 240 if (returntosender(e->e_message, 241 q, (e->e_class >= 0), e) == 0) 242 { 243 state = ESM_DONE; 244 break; 245 } 246 247 /* didn't work -- return to postmaster */ 248 state = ESM_POSTMASTER; 249 break; 250 251 case ESM_POSTMASTER: 252 /* 253 ** Similar to previous case, but to system postmaster. 254 */ 255 256 q = NULL; 257 if (sendtolist("postmaster", NULL, &q, e) <= 0) 258 { 259 syserr("553 cannot parse postmaster!"); 260 ExitStat = EX_SOFTWARE; 261 state = ESM_USRTMP; 262 break; 263 } 264 if (returntosender(e->e_message, 265 q, (e->e_class >= 0), e) == 0) 266 { 267 state = ESM_DONE; 268 break; 269 } 270 271 /* didn't work -- last resort */ 272 state = ESM_USRTMP; 273 break; 274 275 case ESM_DEADLETTER: 276 /* 277 ** Save the message in dead.letter. 278 ** If we weren't mailing back, and the user is 279 ** local, we should save the message in 280 ** ~/dead.letter so that the poor person doesn't 281 ** have to type it over again -- and we all know 282 ** what poor typists UNIX users are. 283 */ 284 285 p = NULL; 286 if (e->e_from.q_mailer == LocalMailer) 287 { 288 if (e->e_from.q_home != NULL) 289 p = e->e_from.q_home; 290 else if ((pw = getpwnam(e->e_from.q_user)) != NULL) 291 p = pw->pw_dir; 292 } 293 if (p == NULL) 294 { 295 /* no local directory */ 296 state = ESM_MAIL; 297 break; 298 } 299 if (e->e_dfp != NULL) 300 { 301 bool oldverb = Verbose; 302 303 /* we have a home directory; open dead.letter */ 304 define('z', p, e); 305 expand("\201z/dead.letter", buf, &buf[sizeof buf - 1], e); 306 Verbose = TRUE; 307 message("Saving message in %s", buf); 308 Verbose = oldverb; 309 e->e_to = buf; 310 q = NULL; 311 (void) sendtolist(buf, &e->e_from, &q, e); 312 if (deliver(e, q) == 0) 313 state = ESM_DONE; 314 else 315 state = ESM_MAIL; 316 } 317 else 318 { 319 /* no data file -- try mailing back */ 320 state = ESM_MAIL; 321 } 322 break; 323 324 case ESM_USRTMP: 325 /* 326 ** Log the mail in /usr/tmp/dead.letter. 327 */ 328 329 if (e->e_class < 0) 330 { 331 state = ESM_DONE; 332 break; 333 } 334 335 fp = dfopen("/usr/tmp/dead.letter", 336 O_WRONLY|O_CREAT|O_APPEND, FileMode); 337 if (fp == NULL) 338 { 339 state = ESM_PANIC; 340 break; 341 } 342 343 putfromline(fp, FileMailer, e); 344 (*e->e_puthdr)(fp, FileMailer, e); 345 putline("\n", fp, FileMailer); 346 (*e->e_putbody)(fp, FileMailer, e, NULL); 347 putline("\n", fp, FileMailer); 348 (void) fflush(fp); 349 state = ferror(fp) ? ESM_PANIC : ESM_DONE; 350 (void) xfclose(fp, "savemail", "/usr/tmp/dead.letter"); 351 break; 352 353 default: 354 syserr("554 savemail: unknown state %d", state); 355 356 /* fall through ... */ 357 358 case ESM_PANIC: 359 /* leave the locked queue & transcript files around */ 360 syserr("554 savemail: cannot save rejected email anywhere"); 361 exit(EX_SOFTWARE); 362 } 363 } 364 } 365 /* 366 ** RETURNTOSENDER -- return a message to the sender with an error. 367 ** 368 ** Parameters: 369 ** msg -- the explanatory message. 370 ** returnq -- the queue of people to send the message to. 371 ** sendbody -- if TRUE, also send back the body of the 372 ** message; otherwise just send the header. 373 ** e -- the current envelope. 374 ** 375 ** Returns: 376 ** zero -- if everything went ok. 377 ** else -- some error. 378 ** 379 ** Side Effects: 380 ** Returns the current message to the sender via 381 ** mail. 382 */ 383 384 static bool SendBody; 385 386 #define MAXRETURNS 6 /* max depth of returning messages */ 387 #define ERRORFUDGE 100 /* nominal size of error message text */ 388 389 returntosender(msg, returnq, sendbody, e) 390 char *msg; 391 ADDRESS *returnq; 392 bool sendbody; 393 register ENVELOPE *e; 394 { 395 char buf[MAXNAME]; 396 extern putheader(), errbody(); 397 register ENVELOPE *ee; 398 ENVELOPE *oldcur = CurEnv; 399 extern ENVELOPE *newenvelope(); 400 ENVELOPE errenvelope; 401 static int returndepth; 402 register ADDRESS *q; 403 404 if (returnq == NULL) 405 return (-1); 406 407 if (msg == NULL) 408 msg = "Unable to deliver mail"; 409 410 if (tTd(6, 1)) 411 { 412 printf("Return To Sender: msg=\"%s\", depth=%d, e=%x, returnq=", 413 msg, returndepth, e); 414 printaddr(returnq, TRUE); 415 } 416 417 if (++returndepth >= MAXRETURNS) 418 { 419 if (returndepth != MAXRETURNS) 420 syserr("554 returntosender: infinite recursion on %s", returnq->q_paddr); 421 /* don't "unrecurse" and fake a clean exit */ 422 /* returndepth--; */ 423 return (0); 424 } 425 426 SendBody = sendbody; 427 define('g', e->e_from.q_paddr, e); 428 ee = newenvelope(&errenvelope, e); 429 define('a', "\201b", ee); 430 define('r', "internal", ee); 431 define('s', "localhost", ee); 432 define('_', "localhost", ee); 433 ee->e_puthdr = putheader; 434 ee->e_putbody = errbody; 435 ee->e_flags |= EF_RESPONSE; 436 if (!bitset(EF_OLDSTYLE, e->e_flags)) 437 ee->e_flags &= ~EF_OLDSTYLE; 438 ee->e_sendqueue = returnq; 439 ee->e_msgsize = e->e_msgsize + ERRORFUDGE; 440 openxscript(ee); 441 for (q = returnq; q != NULL; q = q->q_next) 442 { 443 if (bitset(QBADADDR, q->q_flags)) 444 continue; 445 446 if (!bitset(QDONTSEND, q->q_flags)) 447 ee->e_nrcpts++; 448 449 if (!DontPruneRoutes && pruneroute(q->q_paddr)) 450 parseaddr(q->q_paddr, q, 0, '\0', NULL, e); 451 452 if (q->q_alias == NULL) 453 addheader("To", q->q_paddr, ee); 454 } 455 456 # ifdef LOG 457 if (LogLevel > 5) 458 syslog(LOG_INFO, "%s: %s: return to sender: %s", 459 e->e_id, ee->e_id, msg); 460 # endif 461 462 (void) sprintf(buf, "Returned mail: %s", msg); 463 addheader("Subject", buf, ee); 464 if (SendMIMEErrors) 465 { 466 addheader("MIME-Version", "1.0", ee); 467 (void) sprintf(buf, "%s.%ld/%s", 468 ee->e_id, curtime(), MyHostName); 469 ee->e_msgboundary = newstr(buf); 470 (void) sprintf(buf, "multipart/mixed; boundary=\"%s\"", 471 ee->e_msgboundary); 472 addheader("Content-Type", buf, ee); 473 } 474 475 /* fake up an address header for the from person */ 476 expand("\201n", buf, &buf[sizeof buf - 1], e); 477 if (parseaddr(buf, &ee->e_from, 1, '\0', NULL, e) == NULL) 478 { 479 syserr("553 Can't parse myself!"); 480 ExitStat = EX_SOFTWARE; 481 returndepth--; 482 return (-1); 483 } 484 ee->e_sender = ee->e_from.q_paddr; 485 486 /* push state into submessage */ 487 CurEnv = ee; 488 define('f', "\201n", ee); 489 define('x', "Mail Delivery Subsystem", ee); 490 eatheader(ee, TRUE); 491 492 /* actually deliver the error message */ 493 sendall(ee, SM_DEFAULT); 494 495 /* restore state */ 496 dropenvelope(ee); 497 CurEnv = oldcur; 498 returndepth--; 499 500 /* should check for delivery errors here */ 501 return (0); 502 } 503 /* 504 ** ERRBODY -- output the body of an error message. 505 ** 506 ** Typically this is a copy of the transcript plus a copy of the 507 ** original offending message. 508 ** 509 ** Parameters: 510 ** fp -- the output file. 511 ** m -- the mailer to output to. 512 ** e -- the envelope we are working in. 513 ** 514 ** Returns: 515 ** none 516 ** 517 ** Side Effects: 518 ** Outputs the body of an error message. 519 */ 520 521 errbody(fp, m, e) 522 register FILE *fp; 523 register struct mailer *m; 524 register ENVELOPE *e; 525 { 526 register FILE *xfile; 527 char *p; 528 register ADDRESS *q; 529 bool printheader; 530 char buf[MAXLINE]; 531 532 if (e->e_parent == NULL) 533 { 534 syserr("errbody: null parent"); 535 putline(" ----- Original message lost -----\n", fp, m); 536 return; 537 } 538 539 /* 540 ** Output MIME header. 541 */ 542 543 if (e->e_msgboundary != NULL) 544 { 545 putline("This is a MIME-encapsulated message", fp, m); 546 putline("", fp, m); 547 (void) sprintf(buf, "--%s", e->e_msgboundary); 548 putline(buf, fp, m); 549 putline("", fp, m); 550 } 551 552 /* 553 ** Output error message header (if specified and available). 554 */ 555 556 if (ErrMsgFile != NULL) 557 { 558 if (*ErrMsgFile == '/') 559 { 560 xfile = fopen(ErrMsgFile, "r"); 561 if (xfile != NULL) 562 { 563 while (fgets(buf, sizeof buf, xfile) != NULL) 564 { 565 expand(buf, buf, &buf[sizeof buf - 1], e); 566 putline(buf, fp, m); 567 } 568 (void) fclose(xfile); 569 putline("\n", fp, m); 570 } 571 } 572 else 573 { 574 expand(ErrMsgFile, buf, &buf[sizeof buf - 1], e); 575 putline(buf, fp, m); 576 putline("", fp, m); 577 } 578 } 579 580 /* 581 ** Output message introduction 582 */ 583 584 printheader = TRUE; 585 for (q = e->e_parent->e_sendqueue; q != NULL; q = q->q_next) 586 { 587 if (bitset(QBADADDR, q->q_flags)) 588 { 589 if (printheader) 590 { 591 putline(" ----- The following addresses failed -----", 592 fp, m); 593 printheader = FALSE; 594 } 595 if (q->q_alias != NULL) 596 putline(q->q_alias->q_paddr, fp, m); 597 else 598 putline(q->q_paddr, fp, m); 599 } 600 } 601 if (!printheader) 602 putline("\n", fp, m); 603 604 /* 605 ** Output transcript of errors 606 */ 607 608 (void) fflush(stdout); 609 p = queuename(e->e_parent, 'x'); 610 if ((xfile = fopen(p, "r")) == NULL) 611 { 612 syserr("Cannot open %s", p); 613 putline(" ----- Transcript of session is unavailable -----\n", fp, m); 614 } 615 else 616 { 617 putline(" ----- Transcript of session follows -----\n", fp, m); 618 if (e->e_xfp != NULL) 619 (void) fflush(e->e_xfp); 620 while (fgets(buf, sizeof buf, xfile) != NULL) 621 putline(buf, fp, m); 622 (void) xfclose(xfile, "errbody xscript", p); 623 } 624 errno = 0; 625 626 /* 627 ** Output text of original message 628 */ 629 630 if (NoReturn) 631 SendBody = FALSE; 632 putline("", fp, m); 633 if (e->e_parent->e_df != NULL) 634 { 635 if (SendBody) 636 putline(" ----- Unsent message follows -----\n", fp, m); 637 else 638 putline(" ----- Message header follows -----\n", fp, m); 639 (void) fflush(fp); 640 641 if (e->e_msgboundary != NULL) 642 { 643 putline("", fp, m); 644 (void) sprintf(buf, "--%s", e->e_msgboundary); 645 putline(buf, fp, m); 646 putline("Content-Type: message/rfc822", fp, m); 647 putline("", fp, m); 648 } 649 putheader(fp, m, e->e_parent); 650 putline("", fp, m); 651 if (SendBody) 652 putbody(fp, m, e->e_parent, e->e_msgboundary); 653 else 654 putline(" ----- Message body suppressed -----", fp, m); 655 } 656 else 657 { 658 putline(" ----- No message was collected -----\n", fp, m); 659 } 660 661 if (e->e_msgboundary != NULL) 662 { 663 putline("", fp, m); 664 (void) sprintf(buf, "--%s--", e->e_msgboundary); 665 putline(buf, fp, m); 666 } 667 putline("", fp, m); 668 669 /* 670 ** Cleanup and exit 671 */ 672 673 if (errno != 0) 674 syserr("errbody: I/O error"); 675 } 676 /* 677 ** PRUNEROUTE -- prune an RFC-822 source route 678 ** 679 ** Trims down a source route to the last internet-registered hop. 680 ** This is encouraged by RFC 1123 section 5.3.3. 681 ** 682 ** Parameters: 683 ** addr -- the address 684 ** 685 ** Returns: 686 ** TRUE -- address was modified 687 ** FALSE -- address could not be pruned 688 ** 689 ** Side Effects: 690 ** modifies addr in-place 691 */ 692 693 pruneroute(addr) 694 char *addr; 695 { 696 #ifdef NAMED_BIND 697 char *start, *at, *comma; 698 char c; 699 int rcode; 700 char hostbuf[BUFSIZ]; 701 char *mxhosts[MAXMXHOSTS + 1]; 702 703 /* check to see if this is really a route-addr */ 704 if (*addr != '<' || addr[1] != '@' || addr[strlen(addr) - 1] != '>') 705 return FALSE; 706 start = strchr(addr, ':'); 707 at = strrchr(addr, '@'); 708 if (start == NULL || at == NULL || at < start) 709 return FALSE; 710 711 /* slice off the angle brackets */ 712 strcpy(hostbuf, at + 1); 713 hostbuf[strlen(hostbuf) - 1] = '\0'; 714 715 while (start) 716 { 717 if (getmxrr(hostbuf, mxhosts, FALSE, &rcode) > 0) 718 { 719 strcpy(addr + 1, start + 1); 720 return TRUE; 721 } 722 c = *start; 723 *start = '\0'; 724 comma = strrchr(addr, ','); 725 if (comma && comma[1] == '@') 726 strcpy(hostbuf, comma + 2); 727 else 728 comma = 0; 729 *start = c; 730 start = comma; 731 } 732 #endif 733 return FALSE; 734 } 735