1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2015 */
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 != NULL) 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.");
197 if (eblock->text1 != NULL)
200 " The following error was given:\n\n %s", eblock->text1);
205 #ifdef EXPERIMENTAL_DMARC
206 case ERRMESS_DMARC_FORENSIC:
207 bounce_return_message = TRUE;
208 bounce_return_body = FALSE;
210 "Subject: DMARC Forensic Report for %s from IP %s\n\n",
211 ((eblock == NULL) ? US"Unknown" : eblock->text2),
212 sender_host_address);
214 "A message claiming to be from you has failed the published DMARC\n"
215 "policy for your domain.\n\n");
216 while (eblock != NULL)
218 fprintf(f, " %s: %s\n", eblock->text1, eblock->text2);
220 eblock = eblock->next;
226 fprintf(f, "Subject: Mail failure\n\n");
228 "A message that you sent has caused the error routine to be entered with\n"
229 "an unknown error number (%d).\n", ident);
233 /* Now, if configured, copy the message; first the headers and then the rest of
234 the input if available, up to the configured limit, if the option for including
235 message bodies in bounces is set. */
237 if (bounce_return_message)
239 if (bounce_return_body)
242 "------ This is a copy of your message, including all the headers.");
243 if (size_limit == 0 || size_limit > thismessage_size_limit)
244 size_limit = thismessage_size_limit;
245 if (size_limit > 0 && size_limit < message_size)
255 "------ No more than %d%s characters of the body are included.\n\n",
258 else fprintf(f, " ------\n\n");
263 "------ This is a copy of the headers that were received before the "
264 "error\n was detected.\n\n");
267 /* If the error occurred before the Received: header was created, its text
268 field will still be NULL; just omit such a header line. */
270 while (headers != NULL)
272 if (headers->text != NULL) fprintf(f, "%s", CS headers->text);
273 headers = headers->next;
276 if (ident != ERRMESS_VLONGHEADER && ident != ERRMESS_VLONGHDRLINE)
279 /* After early detection of an error, the message file may be STDIN,
280 in which case we might have to terminate on a line containing just "."
281 as well as on EOF. We may already have the first line in memory. */
283 if (bounce_return_body && message_file != NULL)
287 BOOL enddot = dot_ends && message_file == stdin;
288 if (firstline != NULL) fprintf(f, "%s", CS firstline);
289 while ((ch = fgetc(message_file)) != EOF)
292 if (size_limit > 0 && ++written > size_limit) break;
295 if (state == 0) { if (ch == '\n') state = 1; }
297 { if (ch == '.') state = 2; else if (ch != '\n') state = 0; }
299 { if (ch == '\n') break; else state = 0; }
303 #ifdef EXPERIMENTAL_DMARC
304 /* Overkill, but use exact test in case future code gets inserted */
305 else if (bounce_return_body && message_file == NULL)
307 /* This doesn't print newlines, disable until can parse and fix
308 * output to be legible. */
309 fprintf(f, "%s", expand_string(US"$message_body"));
313 /* Close the file, which should send an EOF to the child process
314 that is receiving the message. Wait for it to finish, without a timeout. */
317 status = child_close(pid, 0); /* Waits for child to close */
320 uschar *msg = US"Child mail process returned status";
322 log_write(0, LOG_MAIN, "%s %d: errno=%d: %s", msg, status, errno,
325 log_write(0, LOG_MAIN, "%s %d", msg, status);
334 /*************************************************
335 * Send message to sender *
336 *************************************************/
338 /* This function is called when errors are detected during the receipt of a
339 message. Delivery failures are handled separately in deliver.c.
341 If there is a valid sender_address, and the failing message is not a local
342 error message, then this function calls moan_send_message to send a message to
343 that person. If the sender's address is null, then an error has occurred with a
344 message that was generated by a mailer daemon. All we can do is to write
345 information to log files. The same action is taken if local_error_message is
346 set - this can happen for non null-senders in certain configurations where exim
347 doesn't run setuid root.
350 ident identifies the particular error
351 eblock chain of error_blocks containing data about the error
352 headers message's headers (chain)
353 message_file a FILE where the body of the message can be read
354 check_sender if TRUE, read the first line of the file for a possible
355 "From " sender (if a trusted caller)
357 Returns: FALSE if there is no sender_address to send to;
358 else the return from moan_send_message()
362 moan_to_sender(int ident, error_block *eblock, header_line *headers,
363 FILE *message_file, BOOL check_sender)
365 uschar *firstline = NULL;
366 uschar *msg = US"Error while reading message with no usable sender address";
368 if (message_reference != NULL)
369 msg = string_sprintf("%s (R=%s)", msg, message_reference);
371 /* Find the sender from a From line if permitted and possible */
373 if (check_sender && message_file != NULL && trusted_caller &&
374 Ufgets(big_buffer, BIG_BUFFER_SIZE, message_file) != NULL)
376 uschar *new_sender = NULL;
377 if (regex_match_and_setup(regex_From, big_buffer, 0, -1))
378 new_sender = expand_string(uucp_from_sender);
379 if (new_sender != NULL) sender_address = new_sender;
380 else firstline = big_buffer;
383 /* If viable sender address, send a message */
385 if (sender_address != NULL && sender_address[0] != 0 && !local_error_message)
386 return moan_send_message(sender_address, ident, eblock, headers,
387 message_file, firstline);
389 /* Otherwise, we can only log */
393 case ERRMESS_BADARGADDRESS:
394 case ERRMESS_BADNOADDRESS:
395 case ERRMESS_BADADDRESS:
396 log_write(0, LOG_MAIN, "%s: at least one malformed recipient address: "
397 "%s - %s", msg, eblock->text1, eblock->text2);
400 case ERRMESS_IGADDRESS:
401 case ERRMESS_NOADDRESS:
402 log_write(0, LOG_MAIN, "%s: no recipient addresses", msg);
405 /* This error has already been logged. */
409 case ERRMESS_VLONGHEADER:
410 log_write(0, LOG_MAIN, "%s: excessively long message header section read "
411 "(more than %d characters)", msg, header_maxsize);
414 case ERRMESS_VLONGHDRLINE:
415 log_write(0, LOG_MAIN, "%s: excessively long message header line read "
416 "(more than %d characters)", msg, header_line_maxsize);
420 log_write(0, LOG_MAIN, "%s: message too big (limit set to %d)", msg,
421 thismessage_size_limit);
424 case ERRMESS_TOOMANYRECIP:
425 log_write(0, LOG_MAIN, "%s: too many recipients (max set to %d)", msg,
429 case ERRMESS_LOCAL_SCAN:
430 log_write(0, LOG_MAIN, "%s: rejected by local_scan: %s", msg, eblock->text1);
433 case ERRMESS_LOCAL_ACL:
434 log_write(0, LOG_MAIN, "%s: rejected by non-SMTP ACL: %s", msg, eblock->text1);
438 log_write(0, LOG_MAIN|LOG_PANIC, "%s: unknown error number %d", msg,
448 /*************************************************
449 * Send message to someone *
450 *************************************************/
452 /* This is called when exim is configured to tell someone (often the
453 mailmaster) about some incident.
456 who address to send mail to
457 addr chain of deferred addresses whose details are to be included
458 subject subject text for the message
459 format a printf() format for the body of the message
460 ... arguments for the format
466 moan_tell_someone(uschar *who, address_item *addr,
467 const uschar *subject, const char *format, ...)
472 int pid = child_open_exim(&fd);
476 DEBUG(D_any) debug_printf("Failed to create child to send message: %s\n",
481 f = fdopen(fd, "wb");
482 fprintf(f, "Auto-Submitted: auto-replied\n");
484 fprintf(f, "To: %s\n", who);
485 fprintf(f, "Subject: %s\n\n", subject);
486 va_start(ap, format);
487 vfprintf(f, format, ap);
492 fprintf(f, "\nThe following address(es) have yet to be delivered:\n");
493 for (; addr != NULL; addr = addr->next)
495 uschar *parent = (addr->parent == NULL)? NULL : addr->parent->address;
496 fprintf(f, " %s", addr->address);
497 if (parent != NULL) fprintf(f, " <%s>", parent);
498 if (addr->basic_errno > 0) fprintf(f, ": %s", strerror(addr->basic_errno));
499 if (addr->message != NULL) fprintf(f, ": %s", addr->message);
505 child_close(pid, 0); /* Waits for child to close; no timeout */
510 /*************************************************
511 * Handle SMTP batch error *
512 *************************************************/
514 /* This is called when something goes wrong in batched (-bS) SMTP input.
515 Information is written to stdout and/or stderr, and Exim exits with a non-zero
516 completion code. BSMTP is almost always called by some other program, so it is
517 up to that program to interpret the return code and do something with the error
518 information, and also to preserve the batch input file for human analysis.
520 Formerly, Exim used to attempt to continue after some errors, but this strategy
521 has been abandoned as it can lead to loss of messages.
524 cmd_buffer the command causing the error, or NULL
525 format a printf() format
526 ... arguments for the format
528 Returns: does not return; exits from the program
529 exit code = 1 if some messages were accepted
530 exit code = 2 if no messages were accepted
534 moan_smtp_batch(uschar *cmd_buffer, const char *format, ...)
537 int yield = (receive_messagecount > 0)? 1 : 2;
539 DEBUG(D_any) debug_printf("Handling error in batched SMTP input\n");
541 /* On stdout, write stuff that a program could parse fairly easily. */
543 va_start(ap, format);
544 vfprintf(stdout, format, ap);
547 fprintf(stdout, "\nTransaction started in line %d\n",
548 bsmtp_transaction_linecount);
549 fprintf(stdout, "Error detected in line %d\n", receive_linecount);
550 if (cmd_buffer != NULL) fprintf(stdout, "%s\n", cmd_buffer);
552 /* On stderr, write stuff for human consumption */
555 "An error was detected while processing a file of BSMTP input.\n"
556 "The error message was:\n\n ");
558 va_start(ap, format);
559 vfprintf(stderr, format, ap);
563 "\n\nThe SMTP transaction started in line %d.\n"
564 "The error was detected in line %d.\n",
565 bsmtp_transaction_linecount, receive_linecount);
567 if (cmd_buffer != NULL)
569 fprintf(stderr, "The SMTP command at fault was:\n\n %s\n\n",
573 fprintf(stderr, "%d previous message%s successfully processed.\n",
574 receive_messagecount, (receive_messagecount == 1)? " was" : "s were");
576 fprintf(stderr, "The rest of the batch was abandoned.\n");
584 /*************************************************
585 * Check for error copies *
586 *************************************************/
588 /* This function is passed the recipient of an error message, and must check
589 the error_copies string to see whether there is an additional recipient list to
590 which errors for this recipient must be bcc'd. The incoming recipient is always
593 Argument: recipient address
594 Returns: additional recipient list or NULL
598 moan_check_errorcopy(uschar *recipient)
600 uschar *item, *localpart, *domain;
601 const uschar *listptr = errors_copy;
602 uschar *yield = NULL;
607 if (errors_copy == NULL) return NULL;
609 /* Set up pointer to the local part and domain, and compute the
610 length of the local part. */
612 localpart = recipient;
613 domain = Ustrrchr(recipient, '@');
614 if (domain == NULL) return NULL; /* should not occur, but avoid crash */
615 llen = domain++ - recipient;
617 /* Scan through the configured items */
619 while ((item = string_nextinlist(&listptr, &sep, buffer, sizeof(buffer)))
622 const uschar *newaddress = item;
623 const uschar *pattern = string_dequote(&newaddress);
625 /* If no new address found, just skip this item. */
627 while (isspace(*newaddress)) newaddress++;
628 if (*newaddress == 0) continue;
630 /* We now have an item to match as an address in item, and the additional
631 address in newaddress. If the pattern matches, expand the new address string
632 and return it. During expansion, make local part and domain available for
633 insertion. This requires a copy to be made; we can't just temporarily
634 terminate it, as the whole address is required for $0. */
636 if (match_address_list(recipient, TRUE, TRUE, &pattern, NULL, 0, UCHAR_MAX+1,
639 deliver_localpart = string_copyn(localpart, llen);
640 deliver_domain = domain;
641 yield = expand_string_copy(newaddress);
642 deliver_domain = deliver_localpart = NULL;
644 log_write(0, LOG_MAIN|LOG_PANIC, "Failed to expand %s when processing "
645 "errors_copy: %s", newaddress, expand_string_message);
650 DEBUG(D_any) debug_printf("errors_copy check returned %s\n",
651 (yield == NULL)? US"NULL" : yield);
659 /************************************************
660 * Handle skipped syntax errors *
661 ************************************************/
663 /* This function is called by the redirect router when it has skipped over one
664 or more syntax errors in the list of addresses. If there is an address to mail
665 to, send a message, and always write the information to the log. In the case of
666 a filter file, a "syntax error" might actually be something else, such as the
667 inability to open a log file. Thus, the wording of the error message is
671 rname the router name
672 eblock chain of error blocks
673 syntax_errors_to address to send mail to, or NULL
674 some TRUE if some addresses were generated; FALSE if none were
675 custom custom message text
677 Returns: FALSE if string expansion failed; TRUE otherwise
681 moan_skipped_syntax_errors(uschar *rname, error_block *eblock,
682 uschar *syntax_errors_to, BOOL some, uschar *custom)
689 for (e = eblock; e != NULL; e = e->next)
691 if (e->text2 != NULL)
692 log_write(0, LOG_MAIN, "%s router: skipped error: %s in \"%s\"",
693 rname, e->text1, e->text2);
695 log_write(0, LOG_MAIN, "%s router: skipped error: %s", rname,
699 if (syntax_errors_to == NULL) return TRUE;
701 s = expand_string(syntax_errors_to);
704 log_write(0, LOG_MAIN, "%s router failed to expand %s: %s", rname,
705 syntax_errors_to, expand_string_message);
709 /* If we can't create a process to send the message, just forget about
712 pid = child_open_exim(&fd);
716 DEBUG(D_any) debug_printf("Failed to create child to send message: %s\n",
721 f = fdopen(fd, "wb");
722 fprintf(f, "Auto-Submitted: auto-replied\n");
724 fprintf(f, "To: %s\n", s);
725 fprintf(f, "Subject: error(s) in forwarding or filtering\n\n");
729 t = expand_string(custom);
732 log_write(0, LOG_MAIN, "%s router failed to expand %s: %s", rname,
733 custom, expand_string_message);
736 fprintf(f, "%s\n\n", t);
739 fprintf(f, "The %s router encountered the following error(s):\n\n",
742 for (e = eblock; e != NULL; e = e->next)
744 fprintf(f, " %s", e->text1);
745 if (e->text2 != NULL)
746 fprintf(f, " in the address\n \"%s\"", e->text2);
751 fprintf(f, "Other addresses were processed normally.\n");
753 fprintf(f, "No valid addresses were generated.\n");
756 child_close(pid, 0); /* Waits for child to close; no timeout */