1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* Functions for sending messages to sender or to mailmaster. */
15 /*************************************************
16 * Write From: line for DSN *
17 *************************************************/
19 /* This function is called to write the From: line in automatically generated
20 messages - bounces, warnings, etc. It expands a configuration item in order to
21 get the text. If the expansion fails, a panic is logged and the default value
22 for the option is used.
24 Argument: the FILE to write to
29 moan_write_from(FILE *f)
31 uschar *s = expand_string(dsn_from);
34 log_write(0, LOG_MAIN|LOG_PANIC,
35 "Failed to expand dsn_from (using default): %s", expand_string_message);
36 s = expand_string(US DEFAULT_DSN_FROM);
38 fprintf(f, "From: %s\n", s);
43 /*************************************************
44 * Send error message *
45 *************************************************/
47 /* This function sends an error message by opening a pipe to a new process
48 running Exim, and writing a message to it using the "-t" option. This is not
49 used for delivery failures, which have their own code for handing failed
53 recipient addressee for the message
54 ident identifies the type of error
55 eblock chain of error_blocks containing data about the error
56 headers the message's headers
57 message_file FILE containing the body of the message
58 firstline contains first line of file, if it was read to check for
59 "From ", but it turned out not to be
61 Returns: TRUE if message successfully sent
65 moan_send_message(uschar *recipient, int ident, error_block *eblock,
66 header_line *headers, FILE *message_file, uschar *firstline)
72 int size_limit = bounce_return_size_limit;
74 int pid = child_open_exim(&fd);
76 /* Creation of child failed */
80 DEBUG(D_any) debug_printf("Failed to create child to send message: %s\n",
84 else DEBUG(D_any) debug_printf("Child process %d for sending message\n", pid);
86 /* Creation of child succeeded */
89 if (errors_reply_to) fprintf(f, "Reply-To: %s\n", errors_reply_to);
90 fprintf(f, "Auto-Submitted: auto-replied\n");
92 fprintf(f, "To: %s\n", recipient);
96 case ERRMESS_BADARGADDRESS:
98 "Subject: Mail failure - malformed recipient address\n\n");
100 "A message that you sent contained a recipient address that was incorrectly\n"
102 fprintf(f, " %s %s\n", eblock->text1, eblock->text2);
103 count = Ustrlen(eblock->text1);
104 if (count > 0 && eblock->text1[count-1] == '.')
106 "\nRecipient addresses must not end with a '.' character.\n");
108 "\nThe message has not been delivered to any recipients.\n");
111 case ERRMESS_BADNOADDRESS:
112 case ERRMESS_BADADDRESS:
114 "Subject: Mail failure - malformed recipient address\n\n");
116 "A message that you sent contained one or more recipient addresses that were\n"
117 "incorrectly constructed:\n\n");
119 while (eblock != NULL)
121 fprintf(f, " %s: %s\n", eblock->text1, eblock->text2);
123 eblock = eblock->next;
126 fprintf(f, (count == 1)? "\nThis address has been ignored. " :
127 "\nThese addresses have been ignored. ");
129 fprintf(f, (ident == ERRMESS_BADADDRESS)?
130 "The other addresses in the message were\n"
131 "syntactically valid and have been passed on for an attempt at delivery.\n" :
133 "There were no other addresses in your\n"
134 "message, and so no attempt at delivery was possible.\n");
137 case ERRMESS_IGADDRESS:
138 fprintf(f, "Subject: Mail failure - no recipient addresses\n\n");
140 "A message that you sent using the -t command line option contained no\n"
141 "addresses that were not also on the command line, and were therefore\n"
142 "suppressed. This left no recipient addresses, and so no delivery could\n"
146 case ERRMESS_NOADDRESS:
147 fprintf(f, "Subject: Mail failure - no recipient addresses\n\n");
149 "A message that you sent contained no recipient addresses, and therefore no\n"
150 "delivery could be attempted.\n");
154 fprintf(f, "Subject: Mail failure - system failure\n\n");
156 "A system failure was encountered while processing a message that you sent,\n"
157 "so it has not been possible to deliver it. The error was:\n\n%s\n",
161 case ERRMESS_VLONGHEADER:
162 fprintf(f, "Subject: Mail failure - overlong header section\n\n");
164 "A message that you sent contained a header section that was excessively\n"
165 "long and could not be handled by the mail transmission software. The\n"
166 "message has not been delivered to any recipients.\n");
169 case ERRMESS_VLONGHDRLINE:
170 fprintf(f, "Subject: Mail failure - overlong header line\n\n");
172 "A message that you sent contained a header line that was excessively\n"
173 "long and could not be handled by the mail transmission software. The\n"
174 "message has not been delivered to any recipients.\n");
178 fprintf(f, "Subject: Mail failure - message too big\n\n");
180 "A message that you sent was longer than the maximum size allowed on this\n"
181 "system. It was not delivered to any recipients.\n");
184 case ERRMESS_TOOMANYRECIP:
185 fprintf(f, "Subject: Mail failure - too many recipients\n\n");
187 "A message that you sent contained more recipients than allowed on this\n"
188 "system. It was not delivered to any recipients.\n");
191 case ERRMESS_LOCAL_SCAN:
192 case ERRMESS_LOCAL_ACL:
193 fprintf(f, "Subject: Mail failure - rejected by local scanning code\n\n");
195 "A message that you sent was rejected by the local scanning code that\n"
196 "checks incoming messages on this system.");
198 fprintf(f, " The following error was given:\n\n %s", eblock->text1);
202 #ifdef EXPERIMENTAL_DMARC
203 case ERRMESS_DMARC_FORENSIC:
204 bounce_return_message = TRUE;
205 bounce_return_body = FALSE;
207 "Subject: DMARC Forensic Report for %s from IP %s\n\n",
208 ((eblock == NULL) ? US"Unknown" : eblock->text2),
209 sender_host_address);
211 "A message claiming to be from you has failed the published DMARC\n"
212 "policy for your domain.\n\n");
213 while (eblock != NULL)
215 fprintf(f, " %s: %s\n", eblock->text1, eblock->text2);
217 eblock = eblock->next;
223 fprintf(f, "Subject: Mail failure\n\n");
225 "A message that you sent has caused the error routine to be entered with\n"
226 "an unknown error number (%d).\n", ident);
230 /* Now, if configured, copy the message; first the headers and then the rest of
231 the input if available, up to the configured limit, if the option for including
232 message bodies in bounces is set. */
234 if (bounce_return_message)
236 if (bounce_return_body)
239 "------ This is a copy of your message, including all the headers.");
240 if (size_limit == 0 || size_limit > thismessage_size_limit)
241 size_limit = thismessage_size_limit;
242 if (size_limit > 0 && size_limit < message_size)
252 "------ No more than %d%s characters of the body are included.\n\n",
255 else fprintf(f, " ------\n\n");
260 "------ This is a copy of the headers that were received before the "
261 "error\n was detected.\n\n");
264 /* If the error occurred before the Received: header was created, its text
265 field will still be NULL; just omit such a header line. */
269 if (headers->text != NULL) fprintf(f, "%s", CS headers->text);
270 headers = headers->next;
273 if (ident != ERRMESS_VLONGHEADER && ident != ERRMESS_VLONGHDRLINE)
276 /* After early detection of an error, the message file may be STDIN,
277 in which case we might have to terminate on a line containing just "."
278 as well as on EOF. We may already have the first line in memory. */
280 if (bounce_return_body && message_file)
282 BOOL enddot = dot_ends && message_file == stdin;
283 uschar * buf = store_get(bounce_return_linesize_limit+2);
285 if (firstline) fprintf(f, "%s", CS firstline);
287 while (fgets(CS buf, bounce_return_linesize_limit+2, message_file))
291 if (enddot && *buf == '.' && buf[1] == '\n')
298 if (buf[len-1] != '\n')
299 { /* eat rest of partial line */
301 while ((ch = fgetc(message_file)) != EOF && ch != '\n') ;
304 if (size_limit > 0 && len > size_limit - written)
306 buf[size_limit - written] = '\0';
314 #ifdef EXPERIMENTAL_DMARC
315 /* Overkill, but use exact test in case future code gets inserted */
316 else if (bounce_return_body && message_file == NULL)
318 /*XXX limit line length here? */
319 /* This doesn't print newlines, disable until can parse and fix
320 * output to be legible. */
321 fprintf(f, "%s", expand_string(US"$message_body"));
325 /* Close the file, which should send an EOF to the child process
326 that is receiving the message. Wait for it to finish, without a timeout. */
329 status = child_close(pid, 0); /* Waits for child to close */
332 uschar *msg = US"Child mail process returned status";
334 log_write(0, LOG_MAIN, "%s %d: errno=%d: %s", msg, status, errno,
337 log_write(0, LOG_MAIN, "%s %d", msg, status);
346 /*************************************************
347 * Send message to sender *
348 *************************************************/
350 /* This function is called when errors are detected during the receipt of a
351 message. Delivery failures are handled separately in deliver.c.
353 If there is a valid sender_address, and the failing message is not a local
354 error message, then this function calls moan_send_message to send a message to
355 that person. If the sender's address is null, then an error has occurred with a
356 message that was generated by a mailer daemon. All we can do is to write
357 information to log files. The same action is taken if local_error_message is
358 set - this can happen for non null-senders in certain configurations where exim
359 doesn't run setuid root.
362 ident identifies the particular error
363 eblock chain of error_blocks containing data about the error
364 headers message's headers (chain)
365 message_file a FILE where the body of the message can be read
366 check_sender if TRUE, read the first line of the file for a possible
367 "From " sender (if a trusted caller)
369 Returns: FALSE if there is no sender_address to send to;
370 else the return from moan_send_message()
374 moan_to_sender(int ident, error_block *eblock, header_line *headers,
375 FILE *message_file, BOOL check_sender)
377 uschar *firstline = NULL;
378 uschar *msg = US"Error while reading message with no usable sender address";
380 if (message_reference)
381 msg = string_sprintf("%s (R=%s)", msg, message_reference);
383 /* Find the sender from a From line if permitted and possible */
385 if (check_sender && message_file && trusted_caller &&
386 Ufgets(big_buffer, BIG_BUFFER_SIZE, message_file) != NULL)
388 uschar *new_sender = NULL;
389 if (regex_match_and_setup(regex_From, big_buffer, 0, -1))
390 new_sender = expand_string(uucp_from_sender);
391 if (new_sender) sender_address = new_sender;
392 else firstline = big_buffer;
395 /* If viable sender address, send a message */
397 if (sender_address && sender_address[0] && !local_error_message)
398 return moan_send_message(sender_address, ident, eblock, headers,
399 message_file, firstline);
401 /* Otherwise, we can only log */
405 case ERRMESS_BADARGADDRESS:
406 case ERRMESS_BADNOADDRESS:
407 case ERRMESS_BADADDRESS:
408 log_write(0, LOG_MAIN, "%s: at least one malformed recipient address: "
409 "%s - %s", msg, eblock->text1, eblock->text2);
412 case ERRMESS_IGADDRESS:
413 case ERRMESS_NOADDRESS:
414 log_write(0, LOG_MAIN, "%s: no recipient addresses", msg);
417 /* This error has already been logged. */
421 case ERRMESS_VLONGHEADER:
422 log_write(0, LOG_MAIN, "%s: excessively long message header section read "
423 "(more than %d characters)", msg, header_maxsize);
426 case ERRMESS_VLONGHDRLINE:
427 log_write(0, LOG_MAIN, "%s: excessively long message header line read "
428 "(more than %d characters)", msg, header_line_maxsize);
432 log_write(0, LOG_MAIN, "%s: message too big (limit set to %d)", msg,
433 thismessage_size_limit);
436 case ERRMESS_TOOMANYRECIP:
437 log_write(0, LOG_MAIN, "%s: too many recipients (max set to %d)", msg,
441 case ERRMESS_LOCAL_SCAN:
442 log_write(0, LOG_MAIN, "%s: rejected by local_scan: %s", msg, eblock->text1);
445 case ERRMESS_LOCAL_ACL:
446 log_write(0, LOG_MAIN, "%s: rejected by non-SMTP ACL: %s", msg, eblock->text1);
450 log_write(0, LOG_MAIN|LOG_PANIC, "%s: unknown error number %d", msg,
460 /*************************************************
461 * Send message to someone *
462 *************************************************/
464 /* This is called when exim is configured to tell someone (often the
465 mailmaster) about some incident.
468 who address to send mail to
469 addr chain of deferred addresses whose details are to be included
470 subject subject text for the message
471 format a printf() format for the body of the message
472 ... arguments for the format
478 moan_tell_someone(uschar *who, address_item *addr,
479 const uschar *subject, const char *format, ...)
484 int pid = child_open_exim(&fd);
488 DEBUG(D_any) debug_printf("Failed to create child to send message: %s\n",
493 f = fdopen(fd, "wb");
494 fprintf(f, "Auto-Submitted: auto-replied\n");
496 fprintf(f, "To: %s\n", who);
497 fprintf(f, "Subject: %s\n\n", subject);
498 va_start(ap, format);
499 vfprintf(f, format, ap);
504 fprintf(f, "\nThe following address(es) have yet to be delivered:\n");
505 for (; addr != NULL; addr = addr->next)
507 uschar *parent = (addr->parent == NULL)? NULL : addr->parent->address;
508 fprintf(f, " %s", addr->address);
509 if (parent != NULL) fprintf(f, " <%s>", parent);
510 if (addr->basic_errno > 0) fprintf(f, ": %s", strerror(addr->basic_errno));
511 if (addr->message != NULL) fprintf(f, ": %s", addr->message);
517 child_close(pid, 0); /* Waits for child to close; no timeout */
522 /*************************************************
523 * Handle SMTP batch error *
524 *************************************************/
526 /* This is called when something goes wrong in batched (-bS) SMTP input.
527 Information is written to stdout and/or stderr, and Exim exits with a non-zero
528 completion code. BSMTP is almost always called by some other program, so it is
529 up to that program to interpret the return code and do something with the error
530 information, and also to preserve the batch input file for human analysis.
532 Formerly, Exim used to attempt to continue after some errors, but this strategy
533 has been abandoned as it can lead to loss of messages.
536 cmd_buffer the command causing the error, or NULL
537 format a printf() format
538 ... arguments for the format
540 Returns: does not return; exits from the program
541 exit code = 1 if some messages were accepted
542 exit code = 2 if no messages were accepted
546 moan_smtp_batch(uschar *cmd_buffer, const char *format, ...)
549 int yield = (receive_messagecount > 0)? 1 : 2;
551 DEBUG(D_any) debug_printf("Handling error in batched SMTP input\n");
553 /* On stdout, write stuff that a program could parse fairly easily. */
555 va_start(ap, format);
556 vfprintf(stdout, format, ap);
559 fprintf(stdout, "\nTransaction started in line %d\n",
560 bsmtp_transaction_linecount);
561 fprintf(stdout, "Error detected in line %d\n", receive_linecount);
562 if (cmd_buffer != NULL) fprintf(stdout, "%s\n", cmd_buffer);
564 /* On stderr, write stuff for human consumption */
567 "An error was detected while processing a file of BSMTP input.\n"
568 "The error message was:\n\n ");
570 va_start(ap, format);
571 vfprintf(stderr, format, ap);
575 "\n\nThe SMTP transaction started in line %d.\n"
576 "The error was detected in line %d.\n",
577 bsmtp_transaction_linecount, receive_linecount);
579 if (cmd_buffer != NULL)
581 fprintf(stderr, "The SMTP command at fault was:\n\n %s\n\n",
585 fprintf(stderr, "%d previous message%s successfully processed.\n",
586 receive_messagecount, (receive_messagecount == 1)? " was" : "s were");
588 fprintf(stderr, "The rest of the batch was abandoned.\n");
596 /*************************************************
597 * Check for error copies *
598 *************************************************/
600 /* This function is passed the recipient of an error message, and must check
601 the error_copies string to see whether there is an additional recipient list to
602 which errors for this recipient must be bcc'd. The incoming recipient is always
605 Argument: recipient address
606 Returns: additional recipient list or NULL
610 moan_check_errorcopy(uschar *recipient)
612 uschar *item, *localpart, *domain;
613 const uschar *listptr = errors_copy;
614 uschar *yield = NULL;
619 if (errors_copy == NULL) return NULL;
621 /* Set up pointer to the local part and domain, and compute the
622 length of the local part. */
624 localpart = recipient;
625 domain = Ustrrchr(recipient, '@');
626 if (domain == NULL) return NULL; /* should not occur, but avoid crash */
627 llen = domain++ - recipient;
629 /* Scan through the configured items */
631 while ((item = string_nextinlist(&listptr, &sep, buffer, sizeof(buffer)))
634 const uschar *newaddress = item;
635 const uschar *pattern = string_dequote(&newaddress);
637 /* If no new address found, just skip this item. */
639 while (isspace(*newaddress)) newaddress++;
640 if (*newaddress == 0) continue;
642 /* We now have an item to match as an address in item, and the additional
643 address in newaddress. If the pattern matches, expand the new address string
644 and return it. During expansion, make local part and domain available for
645 insertion. This requires a copy to be made; we can't just temporarily
646 terminate it, as the whole address is required for $0. */
648 if (match_address_list(recipient, TRUE, TRUE, &pattern, NULL, 0, UCHAR_MAX+1,
651 deliver_localpart = string_copyn(localpart, llen);
652 deliver_domain = domain;
653 yield = expand_string_copy(newaddress);
654 deliver_domain = deliver_localpart = NULL;
656 log_write(0, LOG_MAIN|LOG_PANIC, "Failed to expand %s when processing "
657 "errors_copy: %s", newaddress, expand_string_message);
662 DEBUG(D_any) debug_printf("errors_copy check returned %s\n",
663 (yield == NULL)? US"NULL" : yield);
671 /************************************************
672 * Handle skipped syntax errors *
673 ************************************************/
675 /* This function is called by the redirect router when it has skipped over one
676 or more syntax errors in the list of addresses. If there is an address to mail
677 to, send a message, and always write the information to the log. In the case of
678 a filter file, a "syntax error" might actually be something else, such as the
679 inability to open a log file. Thus, the wording of the error message is
683 rname the router name
684 eblock chain of error blocks
685 syntax_errors_to address to send mail to, or NULL
686 some TRUE if some addresses were generated; FALSE if none were
687 custom custom message text
689 Returns: FALSE if string expansion failed; TRUE otherwise
693 moan_skipped_syntax_errors(uschar *rname, error_block *eblock,
694 uschar *syntax_errors_to, BOOL some, uschar *custom)
701 for (e = eblock; e != NULL; e = e->next)
703 if (e->text2 != NULL)
704 log_write(0, LOG_MAIN, "%s router: skipped error: %s in \"%s\"",
705 rname, e->text1, e->text2);
707 log_write(0, LOG_MAIN, "%s router: skipped error: %s", rname,
711 if (syntax_errors_to == NULL) return TRUE;
713 s = expand_string(syntax_errors_to);
716 log_write(0, LOG_MAIN, "%s router failed to expand %s: %s", rname,
717 syntax_errors_to, expand_string_message);
721 /* If we can't create a process to send the message, just forget about
724 pid = child_open_exim(&fd);
728 DEBUG(D_any) debug_printf("Failed to create child to send message: %s\n",
733 f = fdopen(fd, "wb");
734 fprintf(f, "Auto-Submitted: auto-replied\n");
736 fprintf(f, "To: %s\n", s);
737 fprintf(f, "Subject: error(s) in forwarding or filtering\n\n");
741 t = expand_string(custom);
744 log_write(0, LOG_MAIN, "%s router failed to expand %s: %s", rname,
745 custom, expand_string_message);
748 fprintf(f, "%s\n\n", t);
751 fprintf(f, "The %s router encountered the following error(s):\n\n",
754 for (e = eblock; e != NULL; e = e->next)
756 fprintf(f, " %s", e->text1);
757 if (e->text2 != NULL)
758 fprintf(f, " in the address\n \"%s\"", e->text2);
763 fprintf(f, "Other addresses were processed normally.\n");
765 fprintf(f, "No valid addresses were generated.\n");
768 child_close(pid, 0); /* Waits for child to close; no timeout */