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 6.33 (Berkeley) 04/15/93"; 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; 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 = parseaddr("postmaster", q, 0, '\0', NULL, e); 257 if (q == NULL) 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 auto ADDRESS *q; 302 bool oldverb = Verbose; 303 304 /* we have a home directory; open dead.letter */ 305 define('z', p, e); 306 expand("\201z/dead.letter", buf, &buf[sizeof buf - 1], e); 307 Verbose = TRUE; 308 message("Saving message in %s", buf); 309 Verbose = oldverb; 310 e->e_to = buf; 311 q = NULL; 312 (void) sendtolist(buf, &e->e_from, &q, e); 313 if (deliver(e, q) == 0) 314 state = ESM_DONE; 315 else 316 state = ESM_MAIL; 317 } 318 else 319 { 320 /* no data file -- try mailing back */ 321 state = ESM_MAIL; 322 } 323 break; 324 325 case ESM_USRTMP: 326 /* 327 ** Log the mail in /usr/tmp/dead.letter. 328 */ 329 330 if (e->e_class < 0) 331 { 332 state = ESM_DONE; 333 break; 334 } 335 336 fp = dfopen("/usr/tmp/dead.letter", "a"); 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); 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 (msg == NULL) 405 msg = "Unable to deliver mail"; 406 407 if (tTd(6, 1)) 408 { 409 printf("Return To Sender: msg=\"%s\", depth=%d, e=%x, returnq=", 410 msg, returndepth, e); 411 printaddr(returnq, TRUE); 412 } 413 414 if (++returndepth >= MAXRETURNS) 415 { 416 if (returndepth != MAXRETURNS) 417 syserr("554 returntosender: infinite recursion on %s", returnq->q_paddr); 418 /* don't "unrecurse" and fake a clean exit */ 419 /* returndepth--; */ 420 return (0); 421 } 422 423 SendBody = sendbody; 424 define('g', e->e_from.q_paddr, e); 425 ee = newenvelope(&errenvelope, e); 426 define('a', "\201b", ee); 427 define('r', "internal", ee); 428 define('s', "localhost", ee); 429 define('_', "localhost", ee); 430 ee->e_puthdr = putheader; 431 ee->e_putbody = errbody; 432 ee->e_flags |= EF_RESPONSE; 433 if (!bitset(EF_OLDSTYLE, e->e_flags)) 434 ee->e_flags &= ~EF_OLDSTYLE; 435 ee->e_sendqueue = returnq; 436 ee->e_msgsize = e->e_msgsize + ERRORFUDGE; 437 openxscript(ee); 438 for (q = returnq; q != NULL; q = q->q_next) 439 { 440 if (bitset(QDONTSEND, q->q_flags)) 441 continue; 442 443 ee->e_nrcpts++; 444 445 if (!DontPruneRoutes && pruneroute(q->q_paddr)) 446 parseaddr(q->q_paddr, q, 0, '\0', NULL, e); 447 448 if (q->q_alias == NULL) 449 addheader("to", q->q_paddr, ee); 450 } 451 452 # ifdef LOG 453 if (LogLevel > 5) 454 syslog(LOG_INFO, "%s: %s: return to sender: %s", 455 e->e_id, ee->e_id, msg); 456 # endif 457 458 (void) sprintf(buf, "Returned mail: %s", msg); 459 addheader("subject", buf, ee); 460 461 /* fake up an address header for the from person */ 462 expand("\201n", buf, &buf[sizeof buf - 1], e); 463 if (parseaddr(buf, &ee->e_from, 1, '\0', NULL, e) == NULL) 464 { 465 syserr("553 Can't parse myself!"); 466 ExitStat = EX_SOFTWARE; 467 returndepth--; 468 return (-1); 469 } 470 ee->e_sender = ee->e_from.q_paddr; 471 472 /* push state into submessage */ 473 CurEnv = ee; 474 define('f', "\201n", ee); 475 define('x', "Mail Delivery Subsystem", ee); 476 eatheader(ee, TRUE); 477 478 /* actually deliver the error message */ 479 sendall(ee, SM_DEFAULT); 480 481 /* restore state */ 482 dropenvelope(ee); 483 CurEnv = oldcur; 484 returndepth--; 485 486 /* should check for delivery errors here */ 487 return (0); 488 } 489 /* 490 ** ERRBODY -- output the body of an error message. 491 ** 492 ** Typically this is a copy of the transcript plus a copy of the 493 ** original offending message. 494 ** 495 ** Parameters: 496 ** fp -- the output file. 497 ** m -- the mailer to output to. 498 ** e -- the envelope we are working in. 499 ** 500 ** Returns: 501 ** none 502 ** 503 ** Side Effects: 504 ** Outputs the body of an error message. 505 */ 506 507 errbody(fp, m, e) 508 register FILE *fp; 509 register struct mailer *m; 510 register ENVELOPE *e; 511 { 512 register FILE *xfile; 513 char *p; 514 register ADDRESS *q; 515 bool printheader; 516 char buf[MAXLINE]; 517 518 if (e->e_parent == NULL) 519 { 520 syserr("errbody: null parent"); 521 putline("\n", fp, m); 522 putline(" ----- Original message lost -----\n", fp, m); 523 return; 524 } 525 526 /* 527 ** Output error message header (if specified and available). 528 */ 529 530 if (ErrMsgFile != NULL) 531 { 532 if (*ErrMsgFile == '/') 533 { 534 xfile = fopen(ErrMsgFile, "r"); 535 if (xfile != NULL) 536 { 537 while (fgets(buf, sizeof buf, xfile) != NULL) 538 { 539 expand(buf, buf, &buf[sizeof buf - 1], e); 540 putline(buf, fp, m); 541 } 542 (void) fclose(xfile); 543 putline("\n", fp, m); 544 } 545 } 546 else 547 { 548 expand(ErrMsgFile, buf, &buf[sizeof buf - 1], e); 549 putline(buf, fp, m); 550 putline("\n", fp, m); 551 } 552 } 553 554 /* 555 ** Output message introduction 556 */ 557 558 printheader = TRUE; 559 for (q = e->e_parent->e_sendqueue; q != NULL; q = q->q_next) 560 { 561 if (bitset(QBADADDR, q->q_flags)) 562 { 563 if (printheader) 564 { 565 putline("The following addresses failed:\n", 566 fp, m); 567 printheader = FALSE; 568 } 569 sprintf(buf, "\t%s\n", q->q_paddr); 570 putline(buf, fp, m); 571 } 572 } 573 if (!printheader) 574 putline("\n", fp, m); 575 576 /* 577 ** Output transcript of errors 578 */ 579 580 (void) fflush(stdout); 581 p = queuename(e->e_parent, 'x'); 582 if ((xfile = fopen(p, "r")) == NULL) 583 { 584 syserr("Cannot open %s", p); 585 putline(" ----- Transcript of session is unavailable -----\n", fp, m); 586 } 587 else 588 { 589 putline(" ----- Transcript of session follows -----\n", fp, m); 590 if (e->e_xfp != NULL) 591 (void) fflush(e->e_xfp); 592 while (fgets(buf, sizeof buf, xfile) != NULL) 593 putline(buf, fp, m); 594 (void) xfclose(xfile, "errbody xscript", p); 595 } 596 errno = 0; 597 598 /* 599 ** Output text of original message 600 */ 601 602 if (NoReturn) 603 SendBody = FALSE; 604 if (e->e_parent->e_df != NULL) 605 { 606 if (SendBody) 607 { 608 putline("\n", fp, m); 609 putline(" ----- Unsent message follows -----\n", fp, m); 610 (void) fflush(fp); 611 putheader(fp, m, e->e_parent); 612 putline("\n", fp, m); 613 putbody(fp, m, e->e_parent); 614 } 615 else 616 { 617 putline("\n", fp, m); 618 putline(" ----- Message header follows -----\n", fp, m); 619 (void) fflush(fp); 620 putheader(fp, m, e->e_parent); 621 } 622 } 623 else 624 { 625 putline("\n", fp, m); 626 putline(" ----- No message was collected -----\n", fp, m); 627 putline("\n", fp, m); 628 } 629 630 /* 631 ** Cleanup and exit 632 */ 633 634 if (errno != 0) 635 syserr("errbody: I/O error"); 636 } 637 /* 638 ** PRUNEROUTE -- prune an RFC-822 source route 639 ** 640 ** Trims down a source route to the last internet-registered hop. 641 ** This is encouraged by RFC 1123 section 5.3.3. 642 ** 643 ** Parameters: 644 ** addr -- the address 645 ** 646 ** Returns: 647 ** TRUE -- address was modified 648 ** FALSE -- address could not be pruned 649 ** 650 ** Side Effects: 651 ** modifies addr in-place 652 */ 653 654 pruneroute(addr) 655 char *addr; 656 { 657 #ifdef NAMED_BIND 658 char *start, *at, *comma; 659 char c; 660 int rcode; 661 char hostbuf[BUFSIZ]; 662 char *mxhosts[MAXMXHOSTS + 1]; 663 664 /* check to see if this is really a route-addr */ 665 if (*addr != '<' || addr[1] != '@' || addr[strlen(addr) - 1] != '>') 666 return FALSE; 667 start = strchr(addr, ':'); 668 at = strrchr(addr, '@'); 669 if (start == NULL || at == NULL || at < start) 670 return FALSE; 671 672 /* slice off the angle brackets */ 673 strcpy(hostbuf, at + 1); 674 hostbuf[strlen(hostbuf) - 1] = '\0'; 675 676 while (start) 677 { 678 if (getmxrr(hostbuf, mxhosts, "", &rcode) > 0) 679 { 680 strcpy(addr + 1, start + 1); 681 return TRUE; 682 } 683 c = *start; 684 *start = '\0'; 685 comma = strrchr(addr, ','); 686 if (comma && comma[1] == '@') 687 strcpy(hostbuf, comma + 2); 688 else 689 comma = 0; 690 *start = c; 691 start = comma; 692 } 693 #endif 694 return FALSE; 695 } 696