2628570d8c50427d3ad4ce744187af7a279d31d8
[exim.git] / src / src / receive.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8 /* Code for receiving a message and setting up spool files. */
9
10 #include "exim.h"
11
12 #ifdef EXPERIMENTAL_DCC
13 extern int dcc_ok;
14 #endif
15
16 #ifdef EXPERIMENTAL_DMARC
17 # include "dmarc.h"
18 #endif /* EXPERIMENTAL_DMARC */
19
20 /*************************************************
21 * Local static variables *
22 *************************************************/
23
24 static FILE *data_file = NULL;
25 static int data_fd = -1;
26 static uschar spool_name[256];
27
28
29
30 /*************************************************
31 * Non-SMTP character reading functions *
32 *************************************************/
33
34 /* These are the default functions that are set up in the variables such as
35 receive_getc initially. They just call the standard functions, passing stdin as
36 the file. (When SMTP input is occurring, different functions are used by
37 changing the pointer variables.) */
38
39 int
40 stdin_getc(void)
41 {
42 return getc(stdin);
43 }
44
45 int
46 stdin_ungetc(int c)
47 {
48 return ungetc(c, stdin);
49 }
50
51 int
52 stdin_feof(void)
53 {
54 return feof(stdin);
55 }
56
57 int
58 stdin_ferror(void)
59 {
60 return ferror(stdin);
61 }
62
63
64
65
66 /*************************************************
67 * Check that a set sender is allowed *
68 *************************************************/
69
70 /* This function is called when a local caller sets an explicit sender address.
71 It checks whether this is permitted, which it is for trusted callers.
72 Otherwise, it must match the pattern(s) in untrusted_set_sender.
73
74 Arguments: the proposed sender address
75 Returns: TRUE for a trusted caller
76 TRUE if the address has been set, untrusted_set_sender has been
77 set, and the address matches something in the list
78 FALSE otherwise
79 */
80
81 BOOL
82 receive_check_set_sender(uschar *newsender)
83 {
84 uschar *qnewsender;
85 if (trusted_caller) return TRUE;
86 if (newsender == NULL || untrusted_set_sender == NULL) return FALSE;
87 qnewsender = (Ustrchr(newsender, '@') != NULL)?
88 newsender : string_sprintf("%s@%s", newsender, qualify_domain_sender);
89 return
90 match_address_list(qnewsender, TRUE, TRUE, CUSS &untrusted_set_sender, NULL, -1,
91 0, NULL) == OK;
92 }
93
94
95
96
97 /*************************************************
98 * Read space info for a partition *
99 *************************************************/
100
101 /* This function is called by receive_check_fs() below, and also by string
102 expansion for variables such as $spool_space. The field names for the statvfs
103 structure are macros, because not all OS have F_FAVAIL and it seems tidier to
104 have macros for F_BAVAIL and F_FILES as well. Some kinds of file system do not
105 have inodes, and they return -1 for the number available.
106
107 Later: It turns out that some file systems that do not have the concept of
108 inodes return 0 rather than -1. Such systems should also return 0 for the total
109 number of inodes, so we require that to be greater than zero before returning
110 an inode count.
111
112 Arguments:
113 isspool TRUE for spool partition, FALSE for log partition
114 inodeptr address of int to receive inode count; -1 if there isn't one
115
116 Returns: available on-root space, in kilobytes
117 -1 for log partition if there isn't one
118
119 All values are -1 if the STATFS functions are not available.
120 */
121
122 int
123 receive_statvfs(BOOL isspool, int *inodeptr)
124 {
125 #ifdef HAVE_STATFS
126 struct STATVFS statbuf;
127 uschar *path;
128 uschar *name;
129 uschar buffer[1024];
130
131 /* The spool directory must always exist. */
132
133 if (isspool)
134 {
135 path = spool_directory;
136 name = US"spool";
137 }
138
139 /* Need to cut down the log file path to the directory, and to ignore any
140 appearance of "syslog" in it. */
141
142 else
143 {
144 int sep = ':'; /* Not variable - outside scripts use */
145 const uschar *p = log_file_path;
146 name = US"log";
147
148 /* An empty log_file_path means "use the default". This is the same as an
149 empty item in a list. */
150
151 if (*p == 0) p = US":";
152 while ((path = string_nextinlist(&p, &sep, buffer, sizeof(buffer))))
153 if (Ustrcmp(path, "syslog") != 0)
154 break;
155
156 if (path == NULL) /* No log files */
157 {
158 *inodeptr = -1;
159 return -1;
160 }
161
162 /* An empty string means use the default, which is in the spool directory.
163 But don't just use the spool directory, as it is possible that the log
164 subdirectory has been symbolically linked elsewhere. */
165
166 if (path[0] == 0)
167 {
168 sprintf(CS buffer, CS"%s/log", CS spool_directory);
169 path = buffer;
170 }
171 else
172 {
173 uschar *cp;
174 if ((cp = Ustrrchr(path, '/')) != NULL) *cp = 0;
175 }
176 }
177
178 /* We now have the path; do the business */
179
180 memset(&statbuf, 0, sizeof(statbuf));
181
182 if (STATVFS(CS path, &statbuf) != 0)
183 {
184 log_write(0, LOG_MAIN|LOG_PANIC, "cannot accept message: failed to stat "
185 "%s directory %s: %s", name, spool_directory, strerror(errno));
186 smtp_closedown(US"spool or log directory problem");
187 exim_exit(EXIT_FAILURE);
188 }
189
190 *inodeptr = (statbuf.F_FILES > 0)? statbuf.F_FAVAIL : -1;
191
192 /* Disks are getting huge. Take care with computing the size in kilobytes. */
193
194 return (int)(((double)statbuf.F_BAVAIL * (double)statbuf.F_FRSIZE)/1024.0);
195
196 /* Unable to find partition sizes in this environment. */
197
198 #else
199 *inodeptr = -1;
200 return -1;
201 #endif
202 }
203
204
205
206
207 /*************************************************
208 * Check space on spool and log partitions *
209 *************************************************/
210
211 /* This function is called before accepting a message; if any thresholds are
212 set, it checks them. If a message_size is supplied, it checks that there is
213 enough space for that size plus the threshold - i.e. that the message won't
214 reduce the space to the threshold. Not all OS have statvfs(); for those that
215 don't, this function always returns TRUE. For some OS the old function and
216 struct name statfs is used; that is handled by a macro, defined in exim.h.
217
218 Arguments:
219 msg_size the (estimated) size of an incoming message
220
221 Returns: FALSE if there isn't enough space, or if the information cannot
222 be obtained
223 TRUE if no check was done or there is enough space
224 */
225
226 BOOL
227 receive_check_fs(int msg_size)
228 {
229 int space, inodes;
230
231 if (check_spool_space > 0 || msg_size > 0 || check_spool_inodes > 0)
232 {
233 space = receive_statvfs(TRUE, &inodes);
234
235 DEBUG(D_receive)
236 debug_printf("spool directory space = %dK inodes = %d "
237 "check_space = %dK inodes = %d msg_size = %d\n",
238 space, inodes, check_spool_space, check_spool_inodes, msg_size);
239
240 if ((space >= 0 && space < check_spool_space) ||
241 (inodes >= 0 && inodes < check_spool_inodes))
242 {
243 log_write(0, LOG_MAIN, "spool directory space check failed: space=%d "
244 "inodes=%d", space, inodes);
245 return FALSE;
246 }
247 }
248
249 if (check_log_space > 0 || check_log_inodes > 0)
250 {
251 space = receive_statvfs(FALSE, &inodes);
252
253 DEBUG(D_receive)
254 debug_printf("log directory space = %dK inodes = %d "
255 "check_space = %dK inodes = %d\n",
256 space, inodes, check_log_space, check_log_inodes);
257
258 if ((space >= 0 && space < check_log_space) ||
259 (inodes >= 0 && inodes < check_log_inodes))
260 {
261 log_write(0, LOG_MAIN, "log directory space check failed: space=%d "
262 "inodes=%d", space, inodes);
263 return FALSE;
264 }
265 }
266
267 return TRUE;
268 }
269
270
271
272 /*************************************************
273 * Bomb out while reading a message *
274 *************************************************/
275
276 /* The common case of wanting to bomb out is if a SIGTERM or SIGINT is
277 received, or if there is a timeout. A rarer case might be if the log files are
278 screwed up and Exim can't open them to record a message's arrival. Handling
279 that case is done by setting a flag to cause the log functions to call this
280 function if there is an ultimate disaster. That is why it is globally
281 accessible.
282
283 Arguments:
284 reason text reason to pass to the not-quit ACL
285 msg default SMTP response to give if in an SMTP session
286 Returns: it doesn't
287 */
288
289 void
290 receive_bomb_out(uschar *reason, uschar *msg)
291 {
292 static BOOL already_bombing_out;
293 /* The smtp_notquit_exit() below can call ACLs which can trigger recursive
294 timeouts, if someone has something slow in their quit ACL. Since the only
295 things we should be doing are to close down cleanly ASAP, on the second
296 pass we also close down stuff that might be opened again, before bypassing
297 the ACL call and exiting. */
298
299 /* If spool_name is set, it contains the name of the data file that is being
300 written. Unlink it before closing so that it cannot be picked up by a delivery
301 process. Ensure that any header file is also removed. */
302
303 if (spool_name[0] != '\0')
304 {
305 Uunlink(spool_name);
306 spool_name[Ustrlen(spool_name) - 1] = 'H';
307 Uunlink(spool_name);
308 spool_name[0] = '\0';
309 }
310
311 /* Now close the file if it is open, either as a fd or a stream. */
312
313 if (data_file != NULL)
314 {
315 (void)fclose(data_file);
316 data_file = NULL;
317 } else if (data_fd >= 0) {
318 (void)close(data_fd);
319 data_fd = -1;
320 }
321
322 /* Attempt to close down an SMTP connection tidily. For non-batched SMTP, call
323 smtp_notquit_exit(), which runs the NOTQUIT ACL, if present, and handles the
324 SMTP response. */
325
326 if (!already_bombing_out)
327 {
328 already_bombing_out = TRUE;
329 if (smtp_input)
330 {
331 if (smtp_batched_input)
332 moan_smtp_batch(NULL, "421 %s - message abandoned", msg); /* No return */
333 smtp_notquit_exit(reason, US"421", US"%s %s - closing connection.",
334 smtp_active_hostname, msg);
335 }
336 }
337
338 /* Exit from the program (non-BSMTP cases) */
339
340 exim_exit(EXIT_FAILURE);
341 }
342
343
344 /*************************************************
345 * Data read timeout *
346 *************************************************/
347
348 /* Handler function for timeouts that occur while reading the data that
349 comprises a message.
350
351 Argument: the signal number
352 Returns: nothing
353 */
354
355 static void
356 data_timeout_handler(int sig)
357 {
358 uschar *msg = NULL;
359
360 sig = sig; /* Keep picky compilers happy */
361
362 if (smtp_input)
363 {
364 msg = US"SMTP incoming data timeout";
365 log_write(L_lost_incoming_connection,
366 LOG_MAIN, "SMTP data timeout (message abandoned) on connection "
367 "from %s F=<%s>",
368 (sender_fullhost != NULL)? sender_fullhost : US"local process",
369 sender_address);
370 }
371 else
372 {
373 fprintf(stderr, "exim: timed out while reading - message abandoned\n");
374 log_write(L_lost_incoming_connection,
375 LOG_MAIN, "timed out while reading local message");
376 }
377
378 receive_bomb_out(US"data-timeout", msg); /* Does not return */
379 }
380
381
382
383 /*************************************************
384 * local_scan() timeout *
385 *************************************************/
386
387 /* Handler function for timeouts that occur while running a local_scan()
388 function.
389
390 Argument: the signal number
391 Returns: nothing
392 */
393
394 static void
395 local_scan_timeout_handler(int sig)
396 {
397 sig = sig; /* Keep picky compilers happy */
398 log_write(0, LOG_MAIN|LOG_REJECT, "local_scan() function timed out - "
399 "message temporarily rejected (size %d)", message_size);
400 /* Does not return */
401 receive_bomb_out(US"local-scan-timeout", US"local verification problem");
402 }
403
404
405
406 /*************************************************
407 * local_scan() crashed *
408 *************************************************/
409
410 /* Handler function for signals that occur while running a local_scan()
411 function.
412
413 Argument: the signal number
414 Returns: nothing
415 */
416
417 static void
418 local_scan_crash_handler(int sig)
419 {
420 log_write(0, LOG_MAIN|LOG_REJECT, "local_scan() function crashed with "
421 "signal %d - message temporarily rejected (size %d)", sig, message_size);
422 /* Does not return */
423 receive_bomb_out(US"local-scan-error", US"local verification problem");
424 }
425
426
427 /*************************************************
428 * SIGTERM or SIGINT received *
429 *************************************************/
430
431 /* Handler for SIGTERM or SIGINT signals that occur while reading the
432 data that comprises a message.
433
434 Argument: the signal number
435 Returns: nothing
436 */
437
438 static void
439 data_sigterm_sigint_handler(int sig)
440 {
441 uschar *msg = NULL;
442
443 if (smtp_input)
444 {
445 msg = US"Service not available - SIGTERM or SIGINT received";
446 log_write(0, LOG_MAIN, "%s closed after %s", smtp_get_connection_info(),
447 (sig == SIGTERM)? "SIGTERM" : "SIGINT");
448 }
449 else
450 {
451 if (filter_test == FTEST_NONE)
452 {
453 fprintf(stderr, "\nexim: %s received - message abandoned\n",
454 (sig == SIGTERM)? "SIGTERM" : "SIGINT");
455 log_write(0, LOG_MAIN, "%s received while reading local message",
456 (sig == SIGTERM)? "SIGTERM" : "SIGINT");
457 }
458 }
459
460 receive_bomb_out(US"signal-exit", msg); /* Does not return */
461 }
462
463
464
465 /*************************************************
466 * Add new recipient to list *
467 *************************************************/
468
469 /* This function builds a list of recipient addresses in argc/argv
470 format.
471
472 Arguments:
473 recipient the next address to add to recipients_list
474 pno parent number for fixed aliases; -1 otherwise
475
476 Returns: nothing
477 */
478
479 void
480 receive_add_recipient(uschar *recipient, int pno)
481 {
482 if (recipients_count >= recipients_list_max)
483 {
484 recipient_item *oldlist = recipients_list;
485 int oldmax = recipients_list_max;
486 recipients_list_max = recipients_list_max? 2*recipients_list_max : 50;
487 recipients_list = store_get(recipients_list_max * sizeof(recipient_item));
488 if (oldlist != NULL)
489 memcpy(recipients_list, oldlist, oldmax * sizeof(recipient_item));
490 }
491
492 recipients_list[recipients_count].address = recipient;
493 recipients_list[recipients_count].pno = pno;
494 #ifdef EXPERIMENTAL_BRIGHTMAIL
495 recipients_list[recipients_count].bmi_optin = bmi_current_optin;
496 /* reset optin string pointer for next recipient */
497 bmi_current_optin = NULL;
498 #endif
499 recipients_list[recipients_count].orcpt = NULL;
500 recipients_list[recipients_count].dsn_flags = 0;
501 recipients_list[recipients_count++].errors_to = NULL;
502 }
503
504
505
506
507 /*************************************************
508 * Send user response message *
509 *************************************************/
510
511 /* This function is passed a default response code and a user message. It calls
512 smtp_message_code() to check and possibly modify the response code, and then
513 calls smtp_respond() to transmit the response. I put this into a function
514 just to avoid a lot of repetition.
515
516 Arguments:
517 code the response code
518 user_msg the user message
519
520 Returns: nothing
521 */
522
523 #ifndef DISABLE_PRDR
524 static void
525 smtp_user_msg(uschar *code, uschar *user_msg)
526 {
527 int len = 3;
528 smtp_message_code(&code, &len, &user_msg, NULL, TRUE);
529 smtp_respond(code, len, TRUE, user_msg);
530 }
531 #endif
532
533
534
535
536
537 /*************************************************
538 * Remove a recipient from the list *
539 *************************************************/
540
541 /* This function is provided for local_scan() to use.
542
543 Argument:
544 recipient address to remove
545
546 Returns: TRUE if it did remove something; FALSE otherwise
547 */
548
549 BOOL
550 receive_remove_recipient(uschar *recipient)
551 {
552 int count;
553 DEBUG(D_receive) debug_printf("receive_remove_recipient(\"%s\") called\n",
554 recipient);
555 for (count = 0; count < recipients_count; count++)
556 {
557 if (Ustrcmp(recipients_list[count].address, recipient) == 0)
558 {
559 if ((--recipients_count - count) > 0)
560 memmove(recipients_list + count, recipients_list + count + 1,
561 (recipients_count - count)*sizeof(recipient_item));
562 return TRUE;
563 }
564 }
565 return FALSE;
566 }
567
568
569
570
571
572 /*************************************************
573 * Read data portion of a non-SMTP message *
574 *************************************************/
575
576 /* This function is called to read the remainder of a message (following the
577 header) when the input is not from SMTP - we are receiving a local message on
578 a standard input stream. The message is always terminated by EOF, and is also
579 terminated by a dot on a line by itself if the flag dot_ends is TRUE. Split the
580 two cases for maximum efficiency.
581
582 Ensure that the body ends with a newline. This will naturally be the case when
583 the termination is "\n.\n" but may not be otherwise. The RFC defines messages
584 as "sequences of lines" - this of course strictly applies only to SMTP, but
585 deliveries into BSD-type mailbox files also require it. Exim used to have a
586 flag for doing this at delivery time, but as it was always set for all
587 transports, I decided to simplify things by putting the check here instead.
588
589 There is at least one MUA (dtmail) that sends CRLF via this interface, and
590 other programs are known to do this as well. Exim used to have a option for
591 dealing with this: in July 2003, after much discussion, the code has been
592 changed to default to treat any of LF, CRLF, and bare CR as line terminators.
593
594 However, for the case when a dot on a line by itself terminates a message, the
595 only recognized terminating sequences before and after the dot are LF and CRLF.
596 Otherwise, having read EOL . CR, you don't know whether to read another
597 character or not.
598
599 Internally, in messages stored in Exim's spool files, LF is used as the line
600 terminator. Under the new regime, bare CRs will no longer appear in these
601 files.
602
603 Arguments:
604 fout a FILE to which to write the message
605
606 Returns: One of the END_xxx values indicating why it stopped reading
607 */
608
609 static int
610 read_message_data(FILE *fout)
611 {
612 int ch_state;
613 register int ch;
614 register int linelength = 0;
615
616 /* Handle the case when only EOF terminates the message */
617
618 if (!dot_ends)
619 {
620 register int last_ch = '\n';
621
622 for (; (ch = (receive_getc)()) != EOF; last_ch = ch)
623 {
624 if (ch == 0) body_zerocount++;
625 if (last_ch == '\r' && ch != '\n')
626 {
627 if (linelength > max_received_linelength)
628 max_received_linelength = linelength;
629 linelength = 0;
630 if (fputc('\n', fout) == EOF) return END_WERROR;
631 message_size++;
632 body_linecount++;
633 }
634 if (ch == '\r') continue;
635
636 if (fputc(ch, fout) == EOF) return END_WERROR;
637 if (ch == '\n')
638 {
639 if (linelength > max_received_linelength)
640 max_received_linelength = linelength;
641 linelength = 0;
642 body_linecount++;
643 }
644 else linelength++;
645 if (++message_size > thismessage_size_limit) return END_SIZE;
646 }
647
648 if (last_ch != '\n')
649 {
650 if (linelength > max_received_linelength)
651 max_received_linelength = linelength;
652 if (fputc('\n', fout) == EOF) return END_WERROR;
653 message_size++;
654 body_linecount++;
655 }
656
657 return END_EOF;
658 }
659
660 /* Handle the case when a dot on a line on its own, or EOF, terminates. */
661
662 ch_state = 1;
663
664 while ((ch = (receive_getc)()) != EOF)
665 {
666 if (ch == 0) body_zerocount++;
667 switch (ch_state)
668 {
669 case 0: /* Normal state (previous char written) */
670 if (ch == '\n')
671 {
672 body_linecount++;
673 if (linelength > max_received_linelength)
674 max_received_linelength = linelength;
675 linelength = -1;
676 ch_state = 1;
677 }
678 else if (ch == '\r')
679 { ch_state = 2; continue; }
680 break;
681
682 case 1: /* After written "\n" */
683 if (ch == '.') { ch_state = 3; continue; }
684 if (ch == '\r') { ch_state = 2; continue; }
685 if (ch != '\n') ch_state = 0; else linelength = -1;
686 break;
687
688 case 2:
689 body_linecount++; /* After unwritten "\r" */
690 if (linelength > max_received_linelength)
691 max_received_linelength = linelength;
692 if (ch == '\n')
693 {
694 ch_state = 1;
695 linelength = -1;
696 }
697 else
698 {
699 if (message_size++, fputc('\n', fout) == EOF) return END_WERROR;
700 if (ch == '\r') continue;
701 ch_state = 0;
702 linelength = 0;
703 }
704 break;
705
706 case 3: /* After "\n." (\n written, dot not) */
707 if (ch == '\n') return END_DOT;
708 if (ch == '\r') { ch_state = 4; continue; }
709 message_size++;
710 linelength++;
711 if (fputc('.', fout) == EOF) return END_WERROR;
712 ch_state = 0;
713 break;
714
715 case 4: /* After "\n.\r" (\n written, rest not) */
716 if (ch == '\n') return END_DOT;
717 message_size += 2;
718 body_linecount++;
719 if (fputs(".\n", fout) == EOF) return END_WERROR;
720 if (ch == '\r') { ch_state = 2; continue; }
721 ch_state = 0;
722 break;
723 }
724
725 linelength++;
726 if (fputc(ch, fout) == EOF) return END_WERROR;
727 if (++message_size > thismessage_size_limit) return END_SIZE;
728 }
729
730 /* Get here if EOF read. Unless we have just written "\n", we need to ensure
731 the message ends with a newline, and we must also write any characters that
732 were saved up while testing for an ending dot. */
733
734 if (ch_state != 1)
735 {
736 static uschar *ends[] = { US"\n", NULL, US"\n", US".\n", US".\n" };
737 if (fputs(CS ends[ch_state], fout) == EOF) return END_WERROR;
738 message_size += Ustrlen(ends[ch_state]);
739 body_linecount++;
740 }
741
742 return END_EOF;
743 }
744
745
746
747
748 /*************************************************
749 * Read data portion of an SMTP message *
750 *************************************************/
751
752 /* This function is called to read the remainder of an SMTP message (after the
753 headers), or to skip over it when an error has occurred. In this case, the
754 output file is passed as NULL.
755
756 If any line begins with a dot, that character is skipped. The input should only
757 be successfully terminated by CR LF . CR LF unless it is local (non-network)
758 SMTP, in which case the CRs are optional, but...
759
760 FUDGE: It seems that sites on the net send out messages with just LF
761 terminators, despite the warnings in the RFCs, and other MTAs handle this. So
762 we make the CRs optional in all cases.
763
764 July 2003: Bare CRs cause trouble. We now treat them as line terminators as
765 well, so that there are no CRs in spooled messages. However, the message
766 terminating dot is not recognized between two bare CRs.
767
768 Arguments:
769 fout a FILE to which to write the message; NULL if skipping
770
771 Returns: One of the END_xxx values indicating why it stopped reading
772 */
773
774 static int
775 read_message_data_smtp(FILE *fout)
776 {
777 int ch_state = 0;
778 int ch;
779 register int linelength = 0;
780
781 while ((ch = (receive_getc)()) != EOF)
782 {
783 if (ch == 0) body_zerocount++;
784 switch (ch_state)
785 {
786 case 0: /* After LF or CRLF */
787 if (ch == '.')
788 {
789 ch_state = 3;
790 continue; /* Don't ever write . after LF */
791 }
792 ch_state = 1;
793
794 /* Else fall through to handle as normal uschar. */
795
796 case 1: /* Normal state */
797 if (ch == '\n')
798 {
799 ch_state = 0;
800 body_linecount++;
801 if (linelength > max_received_linelength)
802 max_received_linelength = linelength;
803 linelength = -1;
804 }
805 else if (ch == '\r')
806 {
807 ch_state = 2;
808 continue;
809 }
810 break;
811
812 case 2: /* After (unwritten) CR */
813 body_linecount++;
814 if (linelength > max_received_linelength)
815 max_received_linelength = linelength;
816 linelength = -1;
817 if (ch == '\n')
818 {
819 ch_state = 0;
820 }
821 else
822 {
823 message_size++;
824 if (fout != NULL && fputc('\n', fout) == EOF) return END_WERROR;
825 (void) cutthrough_put_nl();
826 if (ch != '\r') ch_state = 1; else continue;
827 }
828 break;
829
830 case 3: /* After [CR] LF . */
831 if (ch == '\n')
832 return END_DOT;
833 if (ch == '\r')
834 {
835 ch_state = 4;
836 continue;
837 }
838 /* The dot was removed at state 3. For a doubled dot, here, reinstate
839 it to cutthrough. The current ch, dot or not, is passed both to cutthrough
840 and to file below. */
841 if (ch == '.')
842 {
843 uschar c= ch;
844 (void) cutthrough_puts(&c, 1);
845 }
846 ch_state = 1;
847 break;
848
849 case 4: /* After [CR] LF . CR */
850 if (ch == '\n') return END_DOT;
851 message_size++;
852 body_linecount++;
853 if (fout != NULL && fputc('\n', fout) == EOF) return END_WERROR;
854 (void) cutthrough_put_nl();
855 if (ch == '\r')
856 {
857 ch_state = 2;
858 continue;
859 }
860 ch_state = 1;
861 break;
862 }
863
864 /* Add the character to the spool file, unless skipping; then loop for the
865 next. */
866
867 message_size++;
868 linelength++;
869 if (fout != NULL)
870 {
871 if (fputc(ch, fout) == EOF) return END_WERROR;
872 if (message_size > thismessage_size_limit) return END_SIZE;
873 }
874 if(ch == '\n')
875 (void) cutthrough_put_nl();
876 else
877 {
878 uschar c= ch;
879 (void) cutthrough_puts(&c, 1);
880 }
881 }
882
883 /* Fall through here if EOF encountered. This indicates some kind of error,
884 since a correct message is terminated by [CR] LF . [CR] LF. */
885
886 return END_EOF;
887 }
888
889
890
891
892 /*************************************************
893 * Swallow SMTP message *
894 *************************************************/
895
896 /* This function is called when there has been some kind of error while reading
897 an SMTP message, and the remaining data may need to be swallowed. It is global
898 because it is called from smtp_closedown() to shut down an incoming call
899 tidily.
900
901 Argument: a FILE from which to read the message
902 Returns: nothing
903 */
904
905 void
906 receive_swallow_smtp(void)
907 {
908 if (message_ended >= END_NOTENDED)
909 message_ended = read_message_data_smtp(NULL);
910 }
911
912
913
914 /*************************************************
915 * Handle lost SMTP connection *
916 *************************************************/
917
918 /* This function logs connection loss incidents and generates an appropriate
919 SMTP response.
920
921 Argument: additional data for the message
922 Returns: the SMTP response
923 */
924
925 static uschar *
926 handle_lost_connection(uschar *s)
927 {
928 log_write(L_lost_incoming_connection | L_smtp_connection, LOG_MAIN,
929 "%s lost while reading message data%s", smtp_get_connection_info(), s);
930 return US"421 Lost incoming connection";
931 }
932
933
934
935
936 /*************************************************
937 * Handle a non-smtp reception error *
938 *************************************************/
939
940 /* This function is called for various errors during the reception of non-SMTP
941 messages. It either sends a message to the sender of the problem message, or it
942 writes to the standard error stream.
943
944 Arguments:
945 errcode code for moan_to_sender(), identifying the error
946 text1 first message text, passed to moan_to_sender()
947 text2 second message text, used only for stderrr
948 error_rc code to pass to exim_exit if no problem
949 f FILE containing body of message (may be stdin)
950 hptr pointer to instore headers or NULL
951
952 Returns: calls exim_exit(), which does not return
953 */
954
955 static void
956 give_local_error(int errcode, uschar *text1, uschar *text2, int error_rc,
957 FILE *f, header_line *hptr)
958 {
959 if (error_handling == ERRORS_SENDER)
960 {
961 error_block eblock;
962 eblock.next = NULL;
963 eblock.text1 = text1;
964 eblock.text2 = US"";
965 if (!moan_to_sender(errcode, &eblock, hptr, f, FALSE))
966 error_rc = EXIT_FAILURE;
967 }
968 else
969 fprintf(stderr, "exim: %s%s\n", text2, text1); /* Sic */
970 (void)fclose(f);
971 exim_exit(error_rc);
972 }
973
974
975
976 /*************************************************
977 * Add header lines set up by ACL *
978 *************************************************/
979
980 /* This function is called to add the header lines that were set up by
981 statements in an ACL to the list of headers in memory. It is done in two stages
982 like this, because when the ACL for RCPT is running, the other headers have not
983 yet been received. This function is called twice; once just before running the
984 DATA ACL, and once after. This is so that header lines added by MAIL or RCPT
985 are visible to the DATA ACL.
986
987 Originally these header lines were added at the end. Now there is support for
988 three different places: top, bottom, and after the Received: header(s). There
989 will always be at least one Received: header, even if it is marked deleted, and
990 even if something else has been put in front of it.
991
992 Arguments:
993 acl_name text to identify which ACL
994
995 Returns: nothing
996 */
997
998 static void
999 add_acl_headers(int where, uschar *acl_name)
1000 {
1001 header_line *h, *next;
1002 header_line *last_received = NULL;
1003
1004 switch(where)
1005 {
1006 case ACL_WHERE_DKIM:
1007 case ACL_WHERE_MIME:
1008 case ACL_WHERE_DATA:
1009 if (cutthrough.fd >= 0 && (acl_removed_headers || acl_added_headers))
1010 {
1011 log_write(0, LOG_MAIN|LOG_PANIC, "Header modification in data ACLs"
1012 " will not take effect on cutthrough deliveries");
1013 return;
1014 }
1015 }
1016
1017 if (acl_removed_headers != NULL)
1018 {
1019 DEBUG(D_receive|D_acl) debug_printf(">>Headers removed by %s ACL:\n", acl_name);
1020
1021 for (h = header_list; h != NULL; h = h->next) if (h->type != htype_old)
1022 {
1023 const uschar * list = acl_removed_headers;
1024 int sep = ':'; /* This is specified as a colon-separated list */
1025 uschar *s;
1026 uschar buffer[128];
1027
1028 while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer))))
1029 if (header_testname(h, s, Ustrlen(s), FALSE))
1030 {
1031 h->type = htype_old;
1032 DEBUG(D_receive|D_acl) debug_printf(" %s", h->text);
1033 }
1034 }
1035 acl_removed_headers = NULL;
1036 DEBUG(D_receive|D_acl) debug_printf(">>\n");
1037 }
1038
1039 if (acl_added_headers == NULL) return;
1040 DEBUG(D_receive|D_acl) debug_printf(">>Headers added by %s ACL:\n", acl_name);
1041
1042 for (h = acl_added_headers; h != NULL; h = next)
1043 {
1044 next = h->next;
1045
1046 switch(h->type)
1047 {
1048 case htype_add_top:
1049 h->next = header_list;
1050 header_list = h;
1051 DEBUG(D_receive|D_acl) debug_printf(" (at top)");
1052 break;
1053
1054 case htype_add_rec:
1055 if (last_received == NULL)
1056 {
1057 last_received = header_list;
1058 while (!header_testname(last_received, US"Received", 8, FALSE))
1059 last_received = last_received->next;
1060 while (last_received->next != NULL &&
1061 header_testname(last_received->next, US"Received", 8, FALSE))
1062 last_received = last_received->next;
1063 }
1064 h->next = last_received->next;
1065 last_received->next = h;
1066 DEBUG(D_receive|D_acl) debug_printf(" (after Received:)");
1067 break;
1068
1069 case htype_add_rfc:
1070 /* add header before any header which is NOT Received: or Resent- */
1071 last_received = header_list;
1072 while ( (last_received->next != NULL) &&
1073 ( (header_testname(last_received->next, US"Received", 8, FALSE)) ||
1074 (header_testname_incomplete(last_received->next, US"Resent-", 7, FALSE)) ) )
1075 last_received = last_received->next;
1076 /* last_received now points to the last Received: or Resent-* header
1077 in an uninterrupted chain of those header types (seen from the beginning
1078 of all headers. Our current header must follow it. */
1079 h->next = last_received->next;
1080 last_received->next = h;
1081 DEBUG(D_receive|D_acl) debug_printf(" (before any non-Received: or Resent-*: header)");
1082 break;
1083
1084 default:
1085 h->next = NULL;
1086 header_last->next = h;
1087 break;
1088 }
1089
1090 if (h->next == NULL) header_last = h;
1091
1092 /* Check for one of the known header types (From:, To:, etc.) though in
1093 practice most added headers are going to be "other". Lower case
1094 identification letters are never stored with the header; they are used
1095 for existence tests when messages are received. So discard any lower case
1096 flag values. */
1097
1098 h->type = header_checkname(h, FALSE);
1099 if (h->type >= 'a') h->type = htype_other;
1100
1101 DEBUG(D_receive|D_acl) debug_printf(" %s", header_last->text);
1102 }
1103
1104 acl_added_headers = NULL;
1105 DEBUG(D_receive|D_acl) debug_printf(">>\n");
1106 }
1107
1108
1109
1110 /*************************************************
1111 * Add host information for log line *
1112 *************************************************/
1113
1114 /* Called for acceptance and rejecting log lines. This adds information about
1115 the calling host to a string that is being built dynamically.
1116
1117 Arguments:
1118 s the dynamic string
1119 sizeptr points to the size variable
1120 ptrptr points to the pointer variable
1121
1122 Returns: the extended string
1123 */
1124
1125 static uschar *
1126 add_host_info_for_log(uschar *s, int *sizeptr, int *ptrptr)
1127 {
1128 if (sender_fullhost != NULL)
1129 {
1130 s = string_append(s, sizeptr, ptrptr, 2, US" H=", sender_fullhost);
1131 if (LOGGING(incoming_interface) && interface_address != NULL)
1132 {
1133 uschar *ss = string_sprintf(" I=[%s]:%d", interface_address,
1134 interface_port);
1135 s = string_cat(s, sizeptr, ptrptr, ss);
1136 }
1137 }
1138 if (sender_ident != NULL)
1139 s = string_append(s, sizeptr, ptrptr, 2, US" U=", sender_ident);
1140 if (received_protocol != NULL)
1141 s = string_append(s, sizeptr, ptrptr, 2, US" P=", received_protocol);
1142 return s;
1143 }
1144
1145
1146
1147 #ifdef WITH_CONTENT_SCAN
1148
1149 /*************************************************
1150 * Run the MIME ACL on a message *
1151 *************************************************/
1152
1153 /* This code is in a subroutine so that it can be used for both SMTP
1154 and non-SMTP messages. It is called with a non-NULL ACL pointer.
1155
1156 Arguments:
1157 acl The ACL to run (acl_smtp_mime or acl_not_smtp_mime)
1158 smtp_yield_ptr Set FALSE to kill messages after dropped connection
1159 smtp_reply_ptr Where SMTP reply is being built
1160 blackholed_by_ptr Where "blackholed by" message is being built
1161
1162 Returns: TRUE to carry on; FALSE to abandon the message
1163 */
1164
1165 static BOOL
1166 run_mime_acl(uschar *acl, BOOL *smtp_yield_ptr, uschar **smtp_reply_ptr,
1167 uschar **blackholed_by_ptr)
1168 {
1169 FILE *mbox_file;
1170 uschar rfc822_file_path[2048];
1171 unsigned long mbox_size;
1172 header_line *my_headerlist;
1173 uschar *user_msg, *log_msg;
1174 int mime_part_count_buffer = -1;
1175 int rc = OK;
1176
1177 memset(CS rfc822_file_path,0,2048);
1178
1179 /* check if it is a MIME message */
1180 my_headerlist = header_list;
1181 while (my_headerlist != NULL)
1182 {
1183 /* skip deleted headers */
1184 if (my_headerlist->type == '*')
1185 {
1186 my_headerlist = my_headerlist->next;
1187 continue;
1188 }
1189 if (strncmpic(my_headerlist->text, US"Content-Type:", 13) == 0)
1190 {
1191 DEBUG(D_receive) debug_printf("Found Content-Type: header - executing acl_smtp_mime.\n");
1192 goto DO_MIME_ACL;
1193 }
1194 my_headerlist = my_headerlist->next;
1195 }
1196
1197 DEBUG(D_receive) debug_printf("No Content-Type: header - presumably not a MIME message.\n");
1198 return TRUE;
1199
1200 DO_MIME_ACL:
1201 /* make sure the eml mbox file is spooled up */
1202 mbox_file = spool_mbox(&mbox_size, NULL);
1203 if (mbox_file == NULL) {
1204 /* error while spooling */
1205 log_write(0, LOG_MAIN|LOG_PANIC,
1206 "acl_smtp_mime: error while creating mbox spool file, message temporarily rejected.");
1207 Uunlink(spool_name);
1208 unspool_mbox();
1209 #ifdef EXPERIMENTAL_DCC
1210 dcc_ok = 0;
1211 #endif
1212 smtp_respond(US"451", 3, TRUE, US"temporary local problem");
1213 message_id[0] = 0; /* Indicate no message accepted */
1214 *smtp_reply_ptr = US""; /* Indicate reply already sent */
1215 return FALSE; /* Indicate skip to end of receive function */
1216 };
1217
1218 mime_is_rfc822 = 0;
1219
1220 MIME_ACL_CHECK:
1221 mime_part_count = -1;
1222 rc = mime_acl_check(acl, mbox_file, NULL, &user_msg, &log_msg);
1223 (void)fclose(mbox_file);
1224
1225 if (Ustrlen(rfc822_file_path) > 0)
1226 {
1227 mime_part_count = mime_part_count_buffer;
1228
1229 if (unlink(CS rfc822_file_path) == -1)
1230 {
1231 log_write(0, LOG_PANIC,
1232 "acl_smtp_mime: can't unlink RFC822 spool file, skipping.");
1233 goto END_MIME_ACL;
1234 }
1235 }
1236
1237 /* check if we must check any message/rfc822 attachments */
1238 if (rc == OK)
1239 {
1240 uschar temp_path[1024];
1241 struct dirent * entry;
1242 DIR * tempdir;
1243
1244 (void) string_format(temp_path, sizeof(temp_path), "%s/scan/%s",
1245 spool_directory, message_id);
1246
1247 tempdir = opendir(CS temp_path);
1248 for (;;)
1249 {
1250 if (!(entry = readdir(tempdir)))
1251 break;
1252 if (strncmpic(US entry->d_name, US"__rfc822_", 9) == 0)
1253 {
1254 (void) string_format(rfc822_file_path, sizeof(rfc822_file_path),
1255 "%s/scan/%s/%s", spool_directory, message_id, entry->d_name);
1256 debug_printf("RFC822 attachment detected: running MIME ACL for '%s'\n",
1257 rfc822_file_path);
1258 break;
1259 }
1260 }
1261 closedir(tempdir);
1262
1263 if (entry)
1264 {
1265 if ((mbox_file = Ufopen(rfc822_file_path, "rb")))
1266 {
1267 /* set RFC822 expansion variable */
1268 mime_is_rfc822 = 1;
1269 mime_part_count_buffer = mime_part_count;
1270 goto MIME_ACL_CHECK;
1271 }
1272 log_write(0, LOG_PANIC,
1273 "acl_smtp_mime: can't open RFC822 spool file, skipping.");
1274 unlink(CS rfc822_file_path);
1275 }
1276 }
1277
1278 END_MIME_ACL:
1279 add_acl_headers(ACL_WHERE_MIME, US"MIME");
1280 if (rc == DISCARD)
1281 {
1282 recipients_count = 0;
1283 *blackholed_by_ptr = US"MIME ACL";
1284 }
1285 else if (rc != OK)
1286 {
1287 Uunlink(spool_name);
1288 unspool_mbox();
1289 #ifdef EXPERIMENTAL_DCC
1290 dcc_ok = 0;
1291 #endif
1292 if ( smtp_input
1293 && smtp_handle_acl_fail(ACL_WHERE_MIME, rc, user_msg, log_msg) != 0)
1294 {
1295 *smtp_yield_ptr = FALSE; /* No more messages after dropped connection */
1296 *smtp_reply_ptr = US""; /* Indicate reply already sent */
1297 }
1298 message_id[0] = 0; /* Indicate no message accepted */
1299 return FALSE; /* Cause skip to end of receive function */
1300 }
1301
1302 return TRUE;
1303 }
1304
1305 #endif /* WITH_CONTENT_SCAN */
1306
1307
1308
1309 void
1310 received_header_gen(void)
1311 {
1312 uschar *received;
1313 uschar *timestamp;
1314 header_line *received_header= header_list;
1315
1316 timestamp = expand_string(US"${tod_full}");
1317 if (recipients_count == 1) received_for = recipients_list[0].address;
1318 received = expand_string(received_header_text);
1319 received_for = NULL;
1320
1321 if (!received)
1322 {
1323 if(spool_name[0] != 0)
1324 Uunlink(spool_name); /* Lose the data file */
1325 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" "
1326 "(received_header_text) failed: %s", string_printing(received_header_text),
1327 expand_string_message);
1328 }
1329
1330 /* The first element on the header chain is reserved for the Received header,
1331 so all we have to do is fill in the text pointer, and set the type. However, if
1332 the result of the expansion is an empty string, we leave the header marked as
1333 "old" so as to refrain from adding a Received header. */
1334
1335 if (received[0] == 0)
1336 {
1337 received_header->text = string_sprintf("Received: ; %s\n", timestamp);
1338 received_header->type = htype_old;
1339 }
1340 else
1341 {
1342 received_header->text = string_sprintf("%s; %s\n", received, timestamp);
1343 received_header->type = htype_received;
1344 }
1345
1346 received_header->slen = Ustrlen(received_header->text);
1347
1348 DEBUG(D_receive) debug_printf(">>Generated Received: header line\n%c %s",
1349 received_header->type, received_header->text);
1350 }
1351
1352
1353
1354 /*************************************************
1355 * Receive message *
1356 *************************************************/
1357
1358 /* Receive a message on the given input, and put it into a pair of spool files.
1359 Either a non-null list of recipients, or the extract flag will be true, or
1360 both. The flag sender_local is true for locally generated messages. The flag
1361 submission_mode is true if an ACL has obeyed "control = submission". The flag
1362 suppress_local_fixups is true if an ACL has obeyed "control =
1363 suppress_local_fixups" or -G was passed on the command-line.
1364 The flag smtp_input is true if the message is to be
1365 handled using SMTP conventions about termination and lines starting with dots.
1366 For non-SMTP messages, dot_ends is true for dot-terminated messages.
1367
1368 If a message was successfully read, message_id[0] will be non-zero.
1369
1370 The general actions of this function are:
1371
1372 . Read the headers of the message (if any) into a chain of store
1373 blocks.
1374
1375 . If there is a "sender:" header and the message is locally originated,
1376 throw it away, unless the caller is trusted, or unless
1377 active_local_sender_retain is set - which can only happen if
1378 active_local_from_check is false.
1379
1380 . If recipients are to be extracted from the message, build the
1381 recipients list from the headers, removing any that were on the
1382 original recipients list (unless extract_addresses_remove_arguments is
1383 false), and at the same time, remove any bcc header that may be present.
1384
1385 . Get the spool file for the data, sort out its unique name, open
1386 and lock it (but don't give it the name yet).
1387
1388 . Generate a "Message-Id" header if the message doesn't have one, for
1389 locally-originated messages.
1390
1391 . Generate a "Received" header.
1392
1393 . Ensure the recipients list is fully qualified and rewritten if necessary.
1394
1395 . If there are any rewriting rules, apply them to the sender address
1396 and also to the headers.
1397
1398 . If there is no from: header, generate one, for locally-generated messages
1399 and messages in "submission mode" only.
1400
1401 . If the sender is local, check that from: is correct, and if not, generate
1402 a Sender: header, unless message comes from a trusted caller, or this
1403 feature is disabled by active_local_from_check being false.
1404
1405 . If there is no "date" header, generate one, for locally-originated
1406 or submission mode messages only.
1407
1408 . Copy the rest of the input, or up to a terminating "." if in SMTP or
1409 dot_ends mode, to the data file. Leave it open, to hold the lock.
1410
1411 . Write the envelope and the headers to a new file.
1412
1413 . Set the name for the header file; close it.
1414
1415 . Set the name for the data file; close it.
1416
1417 Because this function can potentially be called many times in a single
1418 SMTP connection, all store should be got by store_get(), so that it will be
1419 automatically retrieved after the message is accepted.
1420
1421 FUDGE: It seems that sites on the net send out messages with just LF
1422 terminators, despite the warnings in the RFCs, and other MTAs handle this. So
1423 we make the CRs optional in all cases.
1424
1425 July 2003: Bare CRs in messages, especially in header lines, cause trouble. A
1426 new regime is now in place in which bare CRs in header lines are turned into LF
1427 followed by a space, so as not to terminate the header line.
1428
1429 February 2004: A bare LF in a header line in a message whose first line was
1430 terminated by CRLF is treated in the same way as a bare CR.
1431
1432 Arguments:
1433 extract_recip TRUE if recipients are to be extracted from the message's
1434 headers
1435
1436 Returns: TRUE there are more messages to be read (SMTP input)
1437 FALSE there are no more messages to be read (non-SMTP input
1438 or SMTP connection collapsed, or other failure)
1439
1440 When reading a message for filter testing, the returned value indicates
1441 whether the headers (which is all that is read) were terminated by '.' or
1442 not. */
1443
1444 BOOL
1445 receive_msg(BOOL extract_recip)
1446 {
1447 int i;
1448 int rc = FAIL;
1449 int msg_size = 0;
1450 int process_info_len = Ustrlen(process_info);
1451 int error_rc = (error_handling == ERRORS_SENDER)?
1452 errors_sender_rc : EXIT_FAILURE;
1453 int header_size = 256;
1454 int start, end, domain, size, sptr;
1455 int id_resolution;
1456 int had_zero = 0;
1457 int prevlines_length = 0;
1458
1459 register int ptr = 0;
1460
1461 BOOL contains_resent_headers = FALSE;
1462 BOOL extracted_ignored = FALSE;
1463 BOOL first_line_ended_crlf = TRUE_UNSET;
1464 BOOL smtp_yield = TRUE;
1465 BOOL yield = FALSE;
1466
1467 BOOL resents_exist = FALSE;
1468 uschar *resent_prefix = US"";
1469 uschar *blackholed_by = NULL;
1470 uschar *blackhole_log_msg = US"";
1471 enum {NOT_TRIED, TMP_REJ, PERM_REJ, ACCEPTED} cutthrough_done = NOT_TRIED;
1472
1473 flock_t lock_data;
1474 error_block *bad_addresses = NULL;
1475
1476 uschar *frozen_by = NULL;
1477 uschar *queued_by = NULL;
1478
1479 uschar *errmsg, *s;
1480 struct stat statbuf;
1481
1482 /* Final message to give to SMTP caller, and messages from ACLs */
1483
1484 uschar *smtp_reply = NULL;
1485 uschar *user_msg, *log_msg;
1486
1487 /* Working header pointers */
1488
1489 header_line *h, *next;
1490
1491 /* Flags for noting the existence of certain headers (only one left) */
1492
1493 BOOL date_header_exists = FALSE;
1494
1495 /* Pointers to receive the addresses of headers whose contents we need. */
1496
1497 header_line *from_header = NULL;
1498 header_line *subject_header = NULL;
1499 header_line *msgid_header = NULL;
1500 header_line *received_header;
1501
1502 #ifdef EXPERIMENTAL_DMARC
1503 int dmarc_up = 0;
1504 #endif /* EXPERIMENTAL_DMARC */
1505
1506 /* Variables for use when building the Received: header. */
1507
1508 uschar *timestamp;
1509 int tslen;
1510
1511 /* Release any open files that might have been cached while preparing to
1512 accept the message - e.g. by verifying addresses - because reading a message
1513 might take a fair bit of real time. */
1514
1515 search_tidyup();
1516
1517 /* Extracting the recipient list from an input file is incompatible with
1518 cutthrough delivery with the no-spool option. It shouldn't be possible
1519 to set up the combination, but just in case kill any ongoing connection. */
1520 if (extract_recip || !smtp_input)
1521 cancel_cutthrough_connection("not smtp input");
1522
1523 /* Initialize the chain of headers by setting up a place-holder for Received:
1524 header. Temporarily mark it as "old", i.e. not to be used. We keep header_last
1525 pointing to the end of the chain to make adding headers simple. */
1526
1527 received_header = header_list = header_last = store_get(sizeof(header_line));
1528 header_list->next = NULL;
1529 header_list->type = htype_old;
1530 header_list->text = NULL;
1531 header_list->slen = 0;
1532
1533 /* Control block for the next header to be read. */
1534
1535 next = store_get(sizeof(header_line));
1536 next->text = store_get(header_size);
1537
1538 /* Initialize message id to be null (indicating no message read), and the
1539 header names list to be the normal list. Indicate there is no data file open
1540 yet, initialize the size and warning count, and deal with no size limit. */
1541
1542 message_id[0] = 0;
1543 data_file = NULL;
1544 data_fd = -1;
1545 spool_name[0] = 0;
1546 message_size = 0;
1547 warning_count = 0;
1548 received_count = 1; /* For the one we will add */
1549
1550 if (thismessage_size_limit <= 0) thismessage_size_limit = INT_MAX;
1551
1552 /* While reading the message, the following counts are computed. */
1553
1554 message_linecount = body_linecount = body_zerocount =
1555 max_received_linelength = 0;
1556
1557 #ifndef DISABLE_DKIM
1558 /* Call into DKIM to set up the context. */
1559 if (smtp_input && !smtp_batched_input && !dkim_disable_verify) dkim_exim_verify_init();
1560 #endif
1561
1562 #ifdef EXPERIMENTAL_DMARC
1563 /* initialize libopendmarc */
1564 dmarc_up = dmarc_init();
1565 #endif
1566
1567 /* Remember the time of reception. Exim uses time+pid for uniqueness of message
1568 ids, and fractions of a second are required. See the comments that precede the
1569 message id creation below. */
1570
1571 (void)gettimeofday(&message_id_tv, NULL);
1572
1573 /* For other uses of the received time we can operate with granularity of one
1574 second, and for that we use the global variable received_time. This is for
1575 things like ultimate message timeouts. */
1576
1577 received_time = message_id_tv.tv_sec;
1578
1579 /* If SMTP input, set the special handler for timeouts. The alarm() calls
1580 happen in the smtp_getc() function when it refills its buffer. */
1581
1582 if (smtp_input) os_non_restarting_signal(SIGALRM, data_timeout_handler);
1583
1584 /* If not SMTP input, timeout happens only if configured, and we just set a
1585 single timeout for the whole message. */
1586
1587 else if (receive_timeout > 0)
1588 {
1589 os_non_restarting_signal(SIGALRM, data_timeout_handler);
1590 alarm(receive_timeout);
1591 }
1592
1593 /* SIGTERM and SIGINT are caught always. */
1594
1595 signal(SIGTERM, data_sigterm_sigint_handler);
1596 signal(SIGINT, data_sigterm_sigint_handler);
1597
1598 /* Header lines in messages are not supposed to be very long, though when
1599 unfolded, to: and cc: headers can take up a lot of store. We must also cope
1600 with the possibility of junk being thrown at us. Start by getting 256 bytes for
1601 storing the header, and extend this as necessary using string_cat().
1602
1603 To cope with total lunacies, impose an upper limit on the length of the header
1604 section of the message, as otherwise the store will fill up. We must also cope
1605 with the possibility of binary zeros in the data. Hence we cannot use fgets().
1606 Folded header lines are joined into one string, leaving the '\n' characters
1607 inside them, so that writing them out reproduces the input.
1608
1609 Loop for each character of each header; the next structure for chaining the
1610 header is set up already, with ptr the offset of the next character in
1611 next->text. */
1612
1613 for (;;)
1614 {
1615 int ch = (receive_getc)();
1616
1617 /* If we hit EOF on a SMTP connection, it's an error, since incoming
1618 SMTP must have a correct "." terminator. */
1619
1620 if (ch == EOF && smtp_input /* && !smtp_batched_input */)
1621 {
1622 smtp_reply = handle_lost_connection(US" (header)");
1623 smtp_yield = FALSE;
1624 goto TIDYUP; /* Skip to end of function */
1625 }
1626
1627 /* See if we are at the current header's size limit - there must be at least
1628 four bytes left. This allows for the new character plus a zero, plus two for
1629 extra insertions when we are playing games with dots and carriage returns. If
1630 we are at the limit, extend the text buffer. This could have been done
1631 automatically using string_cat() but because this is a tightish loop storing
1632 only one character at a time, we choose to do it inline. Normally
1633 store_extend() will be able to extend the block; only at the end of a big
1634 store block will a copy be needed. To handle the case of very long headers
1635 (and sometimes lunatic messages can have ones that are 100s of K long) we
1636 call store_release() for strings that have been copied - if the string is at
1637 the start of a block (and therefore the only thing in it, because we aren't
1638 doing any other gets), the block gets freed. We can only do this because we
1639 know there are no other calls to store_get() going on. */
1640
1641 if (ptr >= header_size - 4)
1642 {
1643 int oldsize = header_size;
1644 /* header_size += 256; */
1645 header_size *= 2;
1646 if (!store_extend(next->text, oldsize, header_size))
1647 {
1648 uschar *newtext = store_get(header_size);
1649 memcpy(newtext, next->text, ptr);
1650 store_release(next->text);
1651 next->text = newtext;
1652 }
1653 }
1654
1655 /* Cope with receiving a binary zero. There is dispute about whether
1656 these should be allowed in RFC 822 messages. The middle view is that they
1657 should not be allowed in headers, at least. Exim takes this attitude at
1658 the moment. We can't just stomp on them here, because we don't know that
1659 this line is a header yet. Set a flag to cause scanning later. */
1660
1661 if (ch == 0) had_zero++;
1662
1663 /* Test for termination. Lines in remote SMTP are terminated by CRLF, while
1664 those from data files use just LF. Treat LF in local SMTP input as a
1665 terminator too. Treat EOF as a line terminator always. */
1666
1667 if (ch == EOF) goto EOL;
1668
1669 /* FUDGE: There are sites out there that don't send CRs before their LFs, and
1670 other MTAs accept this. We are therefore forced into this "liberalisation"
1671 too, so we accept LF as a line terminator whatever the source of the message.
1672 However, if the first line of the message ended with a CRLF, we treat a bare
1673 LF specially by inserting a white space after it to ensure that the header
1674 line is not terminated. */
1675
1676 if (ch == '\n')
1677 {
1678 if (first_line_ended_crlf == TRUE_UNSET) first_line_ended_crlf = FALSE;
1679 else if (first_line_ended_crlf) receive_ungetc(' ');
1680 goto EOL;
1681 }
1682
1683 /* This is not the end of the line. If this is SMTP input and this is
1684 the first character in the line and it is a "." character, ignore it.
1685 This implements the dot-doubling rule, though header lines starting with
1686 dots aren't exactly common. They are legal in RFC 822, though. If the
1687 following is CRLF or LF, this is the line that that terminates the
1688 entire message. We set message_ended to indicate this has happened (to
1689 prevent further reading), and break out of the loop, having freed the
1690 empty header, and set next = NULL to indicate no data line. */
1691
1692 if (ptr == 0 && ch == '.' && (smtp_input || dot_ends))
1693 {
1694 ch = (receive_getc)();
1695 if (ch == '\r')
1696 {
1697 ch = (receive_getc)();
1698 if (ch != '\n')
1699 {
1700 receive_ungetc(ch);
1701 ch = '\r'; /* Revert to CR */
1702 }
1703 }
1704 if (ch == '\n')
1705 {
1706 message_ended = END_DOT;
1707 store_reset(next);
1708 next = NULL;
1709 break; /* End character-reading loop */
1710 }
1711
1712 /* For non-SMTP input, the dot at the start of the line was really a data
1713 character. What is now in ch is the following character. We guaranteed
1714 enough space for this above. */
1715
1716 if (!smtp_input)
1717 {
1718 next->text[ptr++] = '.';
1719 message_size++;
1720 }
1721 }
1722
1723 /* If CR is immediately followed by LF, end the line, ignoring the CR, and
1724 remember this case if this is the first line ending. */
1725
1726 if (ch == '\r')
1727 {
1728 ch = (receive_getc)();
1729 if (ch == '\n')
1730 {
1731 if (first_line_ended_crlf == TRUE_UNSET) first_line_ended_crlf = TRUE;
1732 goto EOL;
1733 }
1734
1735 /* Otherwise, put back the character after CR, and turn the bare CR
1736 into LF SP. */
1737
1738 ch = (receive_ungetc)(ch);
1739 next->text[ptr++] = '\n';
1740 message_size++;
1741 ch = ' ';
1742 }
1743
1744 /* We have a data character for the header line. */
1745
1746 next->text[ptr++] = ch; /* Add to buffer */
1747 message_size++; /* Total message size so far */
1748
1749 /* Handle failure due to a humungously long header section. The >= allows
1750 for the terminating \n. Add what we have so far onto the headers list so
1751 that it gets reflected in any error message, and back up the just-read
1752 character. */
1753
1754 if (message_size >= header_maxsize)
1755 {
1756 next->text[ptr] = 0;
1757 next->slen = ptr;
1758 next->type = htype_other;
1759 next->next = NULL;
1760 header_last->next = next;
1761 header_last = next;
1762
1763 log_write(0, LOG_MAIN, "ridiculously long message header received from "
1764 "%s (more than %d characters): message abandoned",
1765 sender_host_unknown? sender_ident : sender_fullhost, header_maxsize);
1766
1767 if (smtp_input)
1768 {
1769 smtp_reply = US"552 Message header is ridiculously long";
1770 receive_swallow_smtp();
1771 goto TIDYUP; /* Skip to end of function */
1772 }
1773
1774 else
1775 {
1776 give_local_error(ERRMESS_VLONGHEADER,
1777 string_sprintf("message header longer than %d characters received: "
1778 "message not accepted", header_maxsize), US"", error_rc, stdin,
1779 header_list->next);
1780 /* Does not return */
1781 }
1782 }
1783
1784 continue; /* With next input character */
1785
1786 /* End of header line reached */
1787
1788 EOL:
1789
1790 /* Keep track of lines for BSMTP errors and overall message_linecount. */
1791
1792 receive_linecount++;
1793 message_linecount++;
1794
1795 /* Keep track of maximum line length */
1796
1797 if (ptr - prevlines_length > max_received_linelength)
1798 max_received_linelength = ptr - prevlines_length;
1799 prevlines_length = ptr + 1;
1800
1801 /* Now put in the terminating newline. There is always space for
1802 at least two more characters. */
1803
1804 next->text[ptr++] = '\n';
1805 message_size++;
1806
1807 /* A blank line signals the end of the headers; release the unwanted
1808 space and set next to NULL to indicate this. */
1809
1810 if (ptr == 1)
1811 {
1812 store_reset(next);
1813 next = NULL;
1814 break;
1815 }
1816
1817 /* There is data in the line; see if the next input character is a
1818 whitespace character. If it is, we have a continuation of this header line.
1819 There is always space for at least one character at this point. */
1820
1821 if (ch != EOF)
1822 {
1823 int nextch = (receive_getc)();
1824 if (nextch == ' ' || nextch == '\t')
1825 {
1826 next->text[ptr++] = nextch;
1827 message_size++;
1828 continue; /* Iterate the loop */
1829 }
1830 else if (nextch != EOF) (receive_ungetc)(nextch); /* For next time */
1831 else ch = EOF; /* Cause main loop to exit at end */
1832 }
1833
1834 /* We have got to the real line end. Terminate the string and release store
1835 beyond it. If it turns out to be a real header, internal binary zeros will
1836 be squashed later. */
1837
1838 next->text[ptr] = 0;
1839 next->slen = ptr;
1840 store_reset(next->text + ptr + 1);
1841
1842 /* Check the running total size against the overall message size limit. We
1843 don't expect to fail here, but if the overall limit is set less than MESSAGE_
1844 MAXSIZE and a big header is sent, we want to catch it. Just stop reading
1845 headers - the code to read the body will then also hit the buffer. */
1846
1847 if (message_size > thismessage_size_limit) break;
1848
1849 /* A line that is not syntactically correct for a header also marks
1850 the end of the headers. In this case, we leave next containing the
1851 first data line. This might actually be several lines because of the
1852 continuation logic applied above, but that doesn't matter.
1853
1854 It turns out that smail, and presumably sendmail, accept leading lines
1855 of the form
1856
1857 From ph10 Fri Jan 5 12:35 GMT 1996
1858
1859 in messages. The "mail" command on Solaris 2 sends such lines. I cannot
1860 find any documentation of this, but for compatibility it had better be
1861 accepted. Exim restricts it to the case of non-smtp messages, and
1862 treats it as an alternative to the -f command line option. Thus it is
1863 ignored except for trusted users or filter testing. Otherwise it is taken
1864 as the sender address, unless -f was used (sendmail compatibility).
1865
1866 It further turns out that some UUCPs generate the From_line in a different
1867 format, e.g.
1868
1869 From ph10 Fri, 7 Jan 97 14:00:00 GMT
1870
1871 The regex for matching these things is now capable of recognizing both
1872 formats (including 2- and 4-digit years in the latter). In fact, the regex
1873 is now configurable, as is the expansion string to fish out the sender.
1874
1875 Even further on it has been discovered that some broken clients send
1876 these lines in SMTP messages. There is now an option to ignore them from
1877 specified hosts or networks. Sigh. */
1878
1879 if (header_last == header_list &&
1880 (!smtp_input
1881 ||
1882 (sender_host_address != NULL &&
1883 verify_check_host(&ignore_fromline_hosts) == OK)
1884 ||
1885 (sender_host_address == NULL && ignore_fromline_local)
1886 ) &&
1887 regex_match_and_setup(regex_From, next->text, 0, -1))
1888 {
1889 if (!sender_address_forced)
1890 {
1891 uschar *uucp_sender = expand_string(uucp_from_sender);
1892 if (uucp_sender == NULL)
1893 {
1894 log_write(0, LOG_MAIN|LOG_PANIC,
1895 "expansion of \"%s\" failed after matching "
1896 "\"From \" line: %s", uucp_from_sender, expand_string_message);
1897 }
1898 else
1899 {
1900 int start, end, domain;
1901 uschar *errmess;
1902 uschar *newsender = parse_extract_address(uucp_sender, &errmess,
1903 &start, &end, &domain, TRUE);
1904 if (newsender != NULL)
1905 {
1906 if (domain == 0 && newsender[0] != 0)
1907 newsender = rewrite_address_qualify(newsender, FALSE);
1908
1909 if (filter_test != FTEST_NONE || receive_check_set_sender(newsender))
1910 {
1911 sender_address = newsender;
1912
1913 if (trusted_caller || filter_test != FTEST_NONE)
1914 {
1915 authenticated_sender = NULL;
1916 originator_name = US"";
1917 sender_local = FALSE;
1918 }
1919
1920 if (filter_test != FTEST_NONE)
1921 printf("Sender taken from \"From \" line\n");
1922 }
1923 }
1924 }
1925 }
1926 }
1927
1928 /* Not a leading "From " line. Check to see if it is a valid header line.
1929 Header names may contain any non-control characters except space and colon,
1930 amazingly. */
1931
1932 else
1933 {
1934 uschar *p = next->text;
1935
1936 /* If not a valid header line, break from the header reading loop, leaving
1937 next != NULL, indicating that it holds the first line of the body. */
1938
1939 if (isspace(*p)) break;
1940 while (mac_isgraph(*p) && *p != ':') p++;
1941 while (isspace(*p)) p++;
1942 if (*p != ':')
1943 {
1944 body_zerocount = had_zero;
1945 break;
1946 }
1947
1948 /* We have a valid header line. If there were any binary zeroes in
1949 the line, stomp on them here. */
1950
1951 if (had_zero > 0)
1952 for (p = next->text; p < next->text + ptr; p++) if (*p == 0) *p = '?';
1953
1954 /* It is perfectly legal to have an empty continuation line
1955 at the end of a header, but it is confusing to humans
1956 looking at such messages, since it looks like a blank line.
1957 Reduce confusion by removing redundant white space at the
1958 end. We know that there is at least one printing character
1959 (the ':' tested for above) so there is no danger of running
1960 off the end. */
1961
1962 p = next->text + ptr - 2;
1963 for (;;)
1964 {
1965 while (*p == ' ' || *p == '\t') p--;
1966 if (*p != '\n') break;
1967 ptr = (p--) - next->text + 1;
1968 message_size -= next->slen - ptr;
1969 next->text[ptr] = 0;
1970 next->slen = ptr;
1971 }
1972
1973 /* Add the header to the chain */
1974
1975 next->type = htype_other;
1976 next->next = NULL;
1977 header_last->next = next;
1978 header_last = next;
1979
1980 /* Check the limit for individual line lengths. This comes after adding to
1981 the chain so that the failing line is reflected if a bounce is generated
1982 (for a local message). */
1983
1984 if (header_line_maxsize > 0 && next->slen > header_line_maxsize)
1985 {
1986 log_write(0, LOG_MAIN, "overlong message header line received from "
1987 "%s (more than %d characters): message abandoned",
1988 sender_host_unknown? sender_ident : sender_fullhost,
1989 header_line_maxsize);
1990
1991 if (smtp_input)
1992 {
1993 smtp_reply = US"552 A message header line is too long";
1994 receive_swallow_smtp();
1995 goto TIDYUP; /* Skip to end of function */
1996 }
1997
1998 else
1999 {
2000 give_local_error(ERRMESS_VLONGHDRLINE,
2001 string_sprintf("message header line longer than %d characters "
2002 "received: message not accepted", header_line_maxsize), US"",
2003 error_rc, stdin, header_list->next);
2004 /* Does not return */
2005 }
2006 }
2007
2008 /* Note if any resent- fields exist. */
2009
2010 if (!resents_exist && strncmpic(next->text, US"resent-", 7) == 0)
2011 {
2012 resents_exist = TRUE;
2013 resent_prefix = US"Resent-";
2014 }
2015 }
2016
2017 /* The line has been handled. If we have hit EOF, break out of the loop,
2018 indicating no pending data line. */
2019
2020 if (ch == EOF) { next = NULL; break; }
2021
2022 /* Set up for the next header */
2023
2024 header_size = 256;
2025 next = store_get(sizeof(header_line));
2026 next->text = store_get(header_size);
2027 ptr = 0;
2028 had_zero = 0;
2029 prevlines_length = 0;
2030 } /* Continue, starting to read the next header */
2031
2032 /* At this point, we have read all the headers into a data structure in main
2033 store. The first header is still the dummy placeholder for the Received: header
2034 we are going to generate a bit later on. If next != NULL, it contains the first
2035 data line - which terminated the headers before reaching a blank line (not the
2036 normal case). */
2037
2038 DEBUG(D_receive)
2039 {
2040 debug_printf(">>Headers received:\n");
2041 for (h = header_list->next; h != NULL; h = h->next)
2042 debug_printf("%s", h->text);
2043 debug_printf("\n");
2044 }
2045
2046 /* End of file on any SMTP connection is an error. If an incoming SMTP call
2047 is dropped immediately after valid headers, the next thing we will see is EOF.
2048 We must test for this specially, as further down the reading of the data is
2049 skipped if already at EOF. */
2050
2051 if (smtp_input && (receive_feof)())
2052 {
2053 smtp_reply = handle_lost_connection(US" (after header)");
2054 smtp_yield = FALSE;
2055 goto TIDYUP; /* Skip to end of function */
2056 }
2057
2058 /* If this is a filter test run and no headers were read, output a warning
2059 in case there is a mistake in the test message. */
2060
2061 if (filter_test != FTEST_NONE && header_list->next == NULL)
2062 printf("Warning: no message headers read\n");
2063
2064
2065 /* Scan the headers to identify them. Some are merely marked for later
2066 processing; some are dealt with here. */
2067
2068 for (h = header_list->next; h != NULL; h = h->next)
2069 {
2070 BOOL is_resent = strncmpic(h->text, US"resent-", 7) == 0;
2071 if (is_resent) contains_resent_headers = TRUE;
2072
2073 switch (header_checkname(h, is_resent))
2074 {
2075 case htype_bcc:
2076 h->type = htype_bcc; /* Both Bcc: and Resent-Bcc: */
2077 break;
2078
2079 case htype_cc:
2080 h->type = htype_cc; /* Both Cc: and Resent-Cc: */
2081 break;
2082
2083 /* Record whether a Date: or Resent-Date: header exists, as appropriate. */
2084
2085 case htype_date:
2086 if (!resents_exist || is_resent) date_header_exists = TRUE;
2087 break;
2088
2089 /* Same comments as about Return-Path: below. */
2090
2091 case htype_delivery_date:
2092 if (delivery_date_remove) h->type = htype_old;
2093 break;
2094
2095 /* Same comments as about Return-Path: below. */
2096
2097 case htype_envelope_to:
2098 if (envelope_to_remove) h->type = htype_old;
2099 break;
2100
2101 /* Mark all "From:" headers so they get rewritten. Save the one that is to
2102 be used for Sender: checking. For Sendmail compatibility, if the "From:"
2103 header consists of just the login id of the user who called Exim, rewrite
2104 it with the gecos field first. Apply this rule to Resent-From: if there
2105 are resent- fields. */
2106
2107 case htype_from:
2108 h->type = htype_from;
2109 if (!resents_exist || is_resent)
2110 {
2111 from_header = h;
2112 if (!smtp_input)
2113 {
2114 int len;
2115 uschar *s = Ustrchr(h->text, ':') + 1;
2116 while (isspace(*s)) s++;
2117 len = h->slen - (s - h->text) - 1;
2118 if (Ustrlen(originator_login) == len &&
2119 strncmpic(s, originator_login, len) == 0)
2120 {
2121 uschar *name = is_resent? US"Resent-From" : US"From";
2122 header_add(htype_from, "%s: %s <%s@%s>\n", name, originator_name,
2123 originator_login, qualify_domain_sender);
2124 from_header = header_last;
2125 h->type = htype_old;
2126 DEBUG(D_receive|D_rewrite)
2127 debug_printf("rewrote \"%s:\" header using gecos\n", name);
2128 }
2129 }
2130 }
2131 break;
2132
2133 /* Identify the Message-id: header for generating "in-reply-to" in the
2134 autoreply transport. For incoming logging, save any resent- value. In both
2135 cases, take just the first of any multiples. */
2136
2137 case htype_id:
2138 if (msgid_header == NULL && (!resents_exist || is_resent))
2139 {
2140 msgid_header = h;
2141 h->type = htype_id;
2142 }
2143 break;
2144
2145 /* Flag all Received: headers */
2146
2147 case htype_received:
2148 h->type = htype_received;
2149 received_count++;
2150 break;
2151
2152 /* "Reply-to:" is just noted (there is no resent-reply-to field) */
2153
2154 case htype_reply_to:
2155 h->type = htype_reply_to;
2156 break;
2157
2158 /* The Return-path: header is supposed to be added to messages when
2159 they leave the SMTP system. We shouldn't receive messages that already
2160 contain Return-path. However, since Exim generates Return-path: on
2161 local delivery, resent messages may well contain it. We therefore
2162 provide an option (which defaults on) to remove any Return-path: headers
2163 on input. Removal actually means flagging as "old", which prevents the
2164 header being transmitted with the message. */
2165
2166 case htype_return_path:
2167 if (return_path_remove) h->type = htype_old;
2168
2169 /* If we are testing a mail filter file, use the value of the
2170 Return-Path: header to set up the return_path variable, which is not
2171 otherwise set. However, remove any <> that surround the address
2172 because the variable doesn't have these. */
2173
2174 if (filter_test != FTEST_NONE)
2175 {
2176 uschar *start = h->text + 12;
2177 uschar *end = start + Ustrlen(start);
2178 while (isspace(*start)) start++;
2179 while (end > start && isspace(end[-1])) end--;
2180 if (*start == '<' && end[-1] == '>')
2181 {
2182 start++;
2183 end--;
2184 }
2185 return_path = string_copyn(start, end - start);
2186 printf("Return-path taken from \"Return-path:\" header line\n");
2187 }
2188 break;
2189
2190 /* If there is a "Sender:" header and the message is locally originated,
2191 and from an untrusted caller and suppress_local_fixups is not set, or if we
2192 are in submission mode for a remote message, mark it "old" so that it will
2193 not be transmitted with the message, unless active_local_sender_retain is
2194 set. (This can only be true if active_local_from_check is false.) If there
2195 are any resent- headers in the message, apply this rule to Resent-Sender:
2196 instead of Sender:. Messages with multiple resent- header sets cannot be
2197 tidily handled. (For this reason, at least one MUA - Pine - turns old
2198 resent- headers into X-resent- headers when resending, leaving just one
2199 set.) */
2200
2201 case htype_sender:
2202 h->type = ((!active_local_sender_retain &&
2203 (
2204 (sender_local && !trusted_caller && !suppress_local_fixups)
2205 || submission_mode
2206 )
2207 ) &&
2208 (!resents_exist||is_resent))?
2209 htype_old : htype_sender;
2210 break;
2211
2212 /* Remember the Subject: header for logging. There is no Resent-Subject */
2213
2214 case htype_subject:
2215 subject_header = h;
2216 break;
2217
2218 /* "To:" gets flagged, and the existence of a recipient header is noted,
2219 whether it's resent- or not. */
2220
2221 case htype_to:
2222 h->type = htype_to;
2223 /****
2224 to_or_cc_header_exists = TRUE;
2225 ****/
2226 break;
2227 }
2228 }
2229
2230 /* Extract recipients from the headers if that is required (the -t option).
2231 Note that this is documented as being done *before* any address rewriting takes
2232 place. There are two possibilities:
2233
2234 (1) According to sendmail documentation for Solaris, IRIX, and HP-UX, any
2235 recipients already listed are to be REMOVED from the message. Smail 3 works
2236 like this. We need to build a non-recipients tree for that list, because in
2237 subsequent processing this data is held in a tree and that's what the
2238 spool_write_header() function expects. Make sure that non-recipient addresses
2239 are fully qualified and rewritten if necessary.
2240
2241 (2) According to other sendmail documentation, -t ADDS extracted recipients to
2242 those in the command line arguments (and it is rumoured some other MTAs do
2243 this). Therefore, there is an option to make Exim behave this way.
2244
2245 *** Notes on "Resent-" header lines ***
2246
2247 The presence of resent-headers in the message makes -t horribly ambiguous.
2248 Experiments with sendmail showed that it uses recipients for all resent-
2249 headers, totally ignoring the concept of "sets of resent- headers" as described
2250 in RFC 2822 section 3.6.6. Sendmail also amalgamates them into a single set
2251 with all the addresses in one instance of each header.
2252
2253 This seems to me not to be at all sensible. Before release 4.20, Exim 4 gave an
2254 error for -t if there were resent- headers in the message. However, after a
2255 discussion on the mailing list, I've learned that there are MUAs that use
2256 resent- headers with -t, and also that the stuff about sets of resent- headers
2257 and their ordering in RFC 2822 is generally ignored. An MUA that submits a
2258 message with -t and resent- header lines makes sure that only *its* resent-
2259 headers are present; previous ones are often renamed as X-resent- for example.
2260
2261 Consequently, Exim has been changed so that, if any resent- header lines are
2262 present, the recipients are taken from all of the appropriate resent- lines,
2263 and not from the ordinary To:, Cc:, etc. */
2264
2265 if (extract_recip)
2266 {
2267 int rcount = 0;
2268 error_block **bnext = &bad_addresses;
2269
2270 if (extract_addresses_remove_arguments)
2271 {
2272 while (recipients_count-- > 0)
2273 {
2274 uschar *s = rewrite_address(recipients_list[recipients_count].address,
2275 TRUE, TRUE, global_rewrite_rules, rewrite_existflags);
2276 tree_add_nonrecipient(s);
2277 }
2278 recipients_list = NULL;
2279 recipients_count = recipients_list_max = 0;
2280 }
2281
2282 /* Now scan the headers */
2283
2284 for (h = header_list->next; h != NULL; h = h->next)
2285 {
2286 if ((h->type == htype_to || h->type == htype_cc || h->type == htype_bcc) &&
2287 (!contains_resent_headers || strncmpic(h->text, US"resent-", 7) == 0))
2288 {
2289 uschar *s = Ustrchr(h->text, ':') + 1;
2290 while (isspace(*s)) s++;
2291
2292 parse_allow_group = TRUE; /* Allow address group syntax */
2293
2294 while (*s != 0)
2295 {
2296 uschar *ss = parse_find_address_end(s, FALSE);
2297 uschar *recipient, *errmess, *p, *pp;
2298 int start, end, domain;
2299
2300 /* Check on maximum */
2301
2302 if (recipients_max > 0 && ++rcount > recipients_max)
2303 {
2304 give_local_error(ERRMESS_TOOMANYRECIP, US"too many recipients",
2305 US"message rejected: ", error_rc, stdin, NULL);
2306 /* Does not return */
2307 }
2308
2309 /* Make a copy of the address, and remove any internal newlines. These
2310 may be present as a result of continuations of the header line. The
2311 white space that follows the newline must not be removed - it is part
2312 of the header. */
2313
2314 pp = recipient = store_get(ss - s + 1);
2315 for (p = s; p < ss; p++) if (*p != '\n') *pp++ = *p;
2316 *pp = 0;
2317
2318 #ifdef SUPPORT_I18N
2319 {
2320 BOOL b = allow_utf8_domains;
2321 allow_utf8_domains = TRUE;
2322 #endif
2323 recipient = parse_extract_address(recipient, &errmess, &start, &end,
2324 &domain, FALSE);
2325
2326 #ifdef SUPPORT_I18N
2327 if (string_is_utf8(recipient))
2328 message_smtputf8 = TRUE;
2329 else
2330 allow_utf8_domains = b;
2331 }
2332 #endif
2333
2334 /* Keep a list of all the bad addresses so we can send a single
2335 error message at the end. However, an empty address is not an error;
2336 just ignore it. This can come from an empty group list like
2337
2338 To: Recipients of list:;
2339
2340 If there are no recipients at all, an error will occur later. */
2341
2342 if (recipient == NULL && Ustrcmp(errmess, "empty address") != 0)
2343 {
2344 int len = Ustrlen(s);
2345 error_block *b = store_get(sizeof(error_block));
2346 while (len > 0 && isspace(s[len-1])) len--;
2347 b->next = NULL;
2348 b->text1 = string_printing(string_copyn(s, len));
2349 b->text2 = errmess;
2350 *bnext = b;
2351 bnext = &(b->next);
2352 }
2353
2354 /* If the recipient is already in the nonrecipients tree, it must
2355 have appeared on the command line with the option extract_addresses_
2356 remove_arguments set. Do not add it to the recipients, and keep a note
2357 that this has happened, in order to give a better error if there are
2358 no recipients left. */
2359
2360 else if (recipient != NULL)
2361 {
2362 if (tree_search(tree_nonrecipients, recipient) == NULL)
2363 receive_add_recipient(recipient, -1);
2364 else
2365 extracted_ignored = TRUE;
2366 }
2367
2368 /* Move on past this address */
2369
2370 s = ss + (*ss? 1:0);
2371 while (isspace(*s)) s++;
2372 } /* Next address */
2373
2374 parse_allow_group = FALSE; /* Reset group syntax flags */
2375 parse_found_group = FALSE;
2376
2377 /* If this was the bcc: header, mark it "old", which means it
2378 will be kept on the spool, but not transmitted as part of the
2379 message. */
2380
2381 if (h->type == htype_bcc) h->type = htype_old;
2382 } /* For appropriate header line */
2383 } /* For each header line */
2384
2385 }
2386
2387 /* Now build the unique message id. This has changed several times over the
2388 lifetime of Exim. This description was rewritten for Exim 4.14 (February 2003).
2389 Retaining all the history in the comment has become too unwieldy - read
2390 previous release sources if you want it.
2391
2392 The message ID has 3 parts: tttttt-pppppp-ss. Each part is a number in base 62.
2393 The first part is the current time, in seconds. The second part is the current
2394 pid. Both are large enough to hold 32-bit numbers in base 62. The third part
2395 can hold a number in the range 0-3843. It used to be a computed sequence
2396 number, but is now the fractional component of the current time in units of
2397 1/2000 of a second (i.e. a value in the range 0-1999). After a message has been
2398 received, Exim ensures that the timer has ticked at the appropriate level
2399 before proceeding, to avoid duplication if the pid happened to be re-used
2400 within the same time period. It seems likely that most messages will take at
2401 least half a millisecond to be received, so no delay will normally be
2402 necessary. At least for some time...
2403
2404 There is a modification when localhost_number is set. Formerly this was allowed
2405 to be as large as 255. Now it is restricted to the range 0-16, and the final
2406 component of the message id becomes (localhost_number * 200) + fractional time
2407 in units of 1/200 of a second (i.e. a value in the range 0-3399).
2408
2409 Some not-really-Unix operating systems use case-insensitive file names (Darwin,
2410 Cygwin). For these, we have to use base 36 instead of base 62. Luckily, this
2411 still allows the tttttt field to hold a large enough number to last for some
2412 more decades, and the final two-digit field can hold numbers up to 1295, which
2413 is enough for milliseconds (instead of 1/2000 of a second).
2414
2415 However, the pppppp field cannot hold a 32-bit pid, but it can hold a 31-bit
2416 pid, so it is probably safe because pids have to be positive. The
2417 localhost_number is restricted to 0-10 for these hosts, and when it is set, the
2418 final field becomes (localhost_number * 100) + fractional time in centiseconds.
2419
2420 Note that string_base62() returns its data in a static storage block, so it
2421 must be copied before calling string_base62() again. It always returns exactly
2422 6 characters.
2423
2424 There doesn't seem to be anything in the RFC which requires a message id to
2425 start with a letter, but Smail was changed to ensure this. The external form of
2426 the message id (as supplied by string expansion) therefore starts with an
2427 additional leading 'E'. The spool file names do not include this leading
2428 letter and it is not used internally.
2429
2430 NOTE: If ever the format of message ids is changed, the regular expression for
2431 checking that a string is in this format must be updated in a corresponding
2432 way. It appears in the initializing code in exim.c. The macro MESSAGE_ID_LENGTH
2433 must also be changed to reflect the correct string length. Then, of course,
2434 other programs that rely on the message id format will need updating too. */
2435
2436 Ustrncpy(message_id, string_base62((long int)(message_id_tv.tv_sec)), 6);
2437 message_id[6] = '-';
2438 Ustrncpy(message_id + 7, string_base62((long int)getpid()), 6);
2439
2440 /* Deal with the case where the host number is set. The value of the number was
2441 checked when it was read, to ensure it isn't too big. The timing granularity is
2442 left in id_resolution so that an appropriate wait can be done after receiving
2443 the message, if necessary (we hope it won't be). */
2444
2445 if (host_number_string != NULL)
2446 {
2447 id_resolution = (BASE_62 == 62)? 5000 : 10000;
2448 sprintf(CS(message_id + MESSAGE_ID_LENGTH - 3), "-%2s",
2449 string_base62((long int)(
2450 host_number * (1000000/id_resolution) +
2451 message_id_tv.tv_usec/id_resolution)) + 4);
2452 }
2453
2454 /* Host number not set: final field is just the fractional time at an
2455 appropriate resolution. */
2456
2457 else
2458 {
2459 id_resolution = (BASE_62 == 62)? 500 : 1000;
2460 sprintf(CS(message_id + MESSAGE_ID_LENGTH - 3), "-%2s",
2461 string_base62((long int)(message_id_tv.tv_usec/id_resolution)) + 4);
2462 }
2463
2464 /* Add the current message id onto the current process info string if
2465 it will fit. */
2466
2467 (void)string_format(process_info + process_info_len,
2468 PROCESS_INFO_SIZE - process_info_len, " id=%s", message_id);
2469
2470 /* If we are using multiple input directories, set up the one for this message
2471 to be the least significant base-62 digit of the time of arrival. Otherwise
2472 ensure that it is an empty string. */
2473
2474 message_subdir[0] = split_spool_directory? message_id[5] : 0;
2475
2476 /* Now that we have the message-id, if there is no message-id: header, generate
2477 one, but only for local (without suppress_local_fixups) or submission mode
2478 messages. This can be user-configured if required, but we had better flatten
2479 any illegal characters therein. */
2480
2481 if (msgid_header == NULL &&
2482 ((sender_host_address == NULL && !suppress_local_fixups)
2483 || submission_mode))
2484 {
2485 uschar *p;
2486 uschar *id_text = US"";
2487 uschar *id_domain = primary_hostname;
2488
2489 /* Permit only letters, digits, dots, and hyphens in the domain */
2490
2491 if (message_id_domain != NULL)
2492 {
2493 uschar *new_id_domain = expand_string(message_id_domain);
2494 if (new_id_domain == NULL)
2495 {
2496 if (!expand_string_forcedfail)
2497 log_write(0, LOG_MAIN|LOG_PANIC,
2498 "expansion of \"%s\" (message_id_header_domain) "
2499 "failed: %s", message_id_domain, expand_string_message);
2500 }
2501 else if (*new_id_domain != 0)
2502 {
2503 id_domain = new_id_domain;
2504 for (p = id_domain; *p != 0; p++)
2505 if (!isalnum(*p) && *p != '.') *p = '-'; /* No need to test '-' ! */
2506 }
2507 }
2508
2509 /* Permit all characters except controls and RFC 2822 specials in the
2510 additional text part. */
2511
2512 if (message_id_text != NULL)
2513 {
2514 uschar *new_id_text = expand_string(message_id_text);
2515 if (new_id_text == NULL)
2516 {
2517 if (!expand_string_forcedfail)
2518 log_write(0, LOG_MAIN|LOG_PANIC,
2519 "expansion of \"%s\" (message_id_header_text) "
2520 "failed: %s", message_id_text, expand_string_message);
2521 }
2522 else if (*new_id_text != 0)
2523 {
2524 id_text = new_id_text;
2525 for (p = id_text; *p != 0; p++)
2526 if (mac_iscntrl_or_special(*p)) *p = '-';
2527 }
2528 }
2529
2530 /* Add the header line
2531 * Resent-* headers are prepended, per RFC 5322 3.6.6. Non-Resent-* are
2532 * appended, to preserve classical expectations of header ordering. */
2533
2534 header_add_at_position(!resents_exist, NULL, FALSE, htype_id,
2535 "%sMessage-Id: <%s%s%s@%s>\n", resent_prefix, message_id_external,
2536 (*id_text == 0)? "" : ".", id_text, id_domain);
2537 }
2538
2539 /* If we are to log recipients, keep a copy of the raw ones before any possible
2540 rewriting. Must copy the count, because later ACLs and the local_scan()
2541 function may mess with the real recipients. */
2542
2543 if (LOGGING(received_recipients))
2544 {
2545 raw_recipients = store_get(recipients_count * sizeof(uschar *));
2546 for (i = 0; i < recipients_count; i++)
2547 raw_recipients[i] = string_copy(recipients_list[i].address);
2548 raw_recipients_count = recipients_count;
2549 }
2550
2551 /* Ensure the recipients list is fully qualified and rewritten. Unqualified
2552 recipients will get here only if the conditions were right (allow_unqualified_
2553 recipient is TRUE). */
2554
2555 for (i = 0; i < recipients_count; i++)
2556 recipients_list[i].address =
2557 rewrite_address(recipients_list[i].address, TRUE, TRUE,
2558 global_rewrite_rules, rewrite_existflags);
2559
2560 /* If there is no From: header, generate one for local (without
2561 suppress_local_fixups) or submission_mode messages. If there is no sender
2562 address, but the sender is local or this is a local delivery error, use the
2563 originator login. This shouldn't happen for genuine bounces, but might happen
2564 for autoreplies. The addition of From: must be done *before* checking for the
2565 possible addition of a Sender: header, because untrusted_set_sender allows an
2566 untrusted user to set anything in the envelope (which might then get info
2567 From:) but we still want to ensure a valid Sender: if it is required. */
2568
2569 if (from_header == NULL &&
2570 ((sender_host_address == NULL && !suppress_local_fixups)
2571 || submission_mode))
2572 {
2573 uschar *oname = US"";
2574
2575 /* Use the originator_name if this is a locally submitted message and the
2576 caller is not trusted. For trusted callers, use it only if -F was used to
2577 force its value or if we have a non-SMTP message for which -f was not used
2578 to set the sender. */
2579
2580 if (sender_host_address == NULL)
2581 {
2582 if (!trusted_caller || sender_name_forced ||
2583 (!smtp_input && !sender_address_forced))
2584 oname = originator_name;
2585 }
2586
2587 /* For non-locally submitted messages, the only time we use the originator
2588 name is when it was forced by the /name= option on control=submission. */
2589
2590 else
2591 {
2592 if (submission_name != NULL) oname = submission_name;
2593 }
2594
2595 /* Envelope sender is empty */
2596
2597 if (sender_address[0] == 0)
2598 {
2599 uschar *fromstart, *fromend;
2600
2601 fromstart = string_sprintf("%sFrom: %s%s", resent_prefix,
2602 oname, (oname[0] == 0)? "" : " <");
2603 fromend = (oname[0] == 0)? US"" : US">";
2604
2605 if (sender_local || local_error_message)
2606 {
2607 header_add(htype_from, "%s%s@%s%s\n", fromstart,
2608 local_part_quote(originator_login), qualify_domain_sender,
2609 fromend);
2610 }
2611 else if (submission_mode && authenticated_id != NULL)
2612 {
2613 if (submission_domain == NULL)
2614 {
2615 header_add(htype_from, "%s%s@%s%s\n", fromstart,
2616 local_part_quote(authenticated_id), qualify_domain_sender,
2617 fromend);
2618 }
2619 else if (submission_domain[0] == 0) /* empty => whole address set */
2620 {
2621 header_add(htype_from, "%s%s%s\n", fromstart, authenticated_id,
2622 fromend);
2623 }
2624 else
2625 {
2626 header_add(htype_from, "%s%s@%s%s\n", fromstart,
2627 local_part_quote(authenticated_id), submission_domain,
2628 fromend);
2629 }
2630 from_header = header_last; /* To get it checked for Sender: */
2631 }
2632 }
2633
2634 /* There is a non-null envelope sender. Build the header using the original
2635 sender address, before any rewriting that might have been done while
2636 verifying it. */
2637
2638 else
2639 {
2640 header_add(htype_from, "%sFrom: %s%s%s%s\n", resent_prefix,
2641 oname,
2642 (oname[0] == 0)? "" : " <",
2643 (sender_address_unrewritten == NULL)?
2644 sender_address : sender_address_unrewritten,
2645 (oname[0] == 0)? "" : ">");
2646
2647 from_header = header_last; /* To get it checked for Sender: */
2648 }
2649 }
2650
2651
2652 /* If the sender is local (without suppress_local_fixups), or if we are in
2653 submission mode and there is an authenticated_id, check that an existing From:
2654 is correct, and if not, generate a Sender: header, unless disabled. Any
2655 previously-existing Sender: header was removed above. Note that sender_local,
2656 as well as being TRUE if the caller of exim is not trusted, is also true if a
2657 trusted caller did not supply a -f argument for non-smtp input. To allow
2658 trusted callers to forge From: without supplying -f, we have to test explicitly
2659 here. If the From: header contains more than one address, then the call to
2660 parse_extract_address fails, and a Sender: header is inserted, as required. */
2661
2662 if (from_header != NULL &&
2663 (active_local_from_check &&
2664 ((sender_local && !trusted_caller && !suppress_local_fixups) ||
2665 (submission_mode && authenticated_id != NULL))
2666 ))
2667 {
2668 BOOL make_sender = TRUE;
2669 int start, end, domain;
2670 uschar *errmess;
2671 uschar *from_address =
2672 parse_extract_address(Ustrchr(from_header->text, ':') + 1, &errmess,
2673 &start, &end, &domain, FALSE);
2674 uschar *generated_sender_address;
2675
2676 if (submission_mode)
2677 {
2678 if (submission_domain == NULL)
2679 {
2680 generated_sender_address = string_sprintf("%s@%s",
2681 local_part_quote(authenticated_id), qualify_domain_sender);
2682 }
2683 else if (submission_domain[0] == 0) /* empty => full address */
2684 {
2685 generated_sender_address = string_sprintf("%s",
2686 authenticated_id);
2687 }
2688 else
2689 {
2690 generated_sender_address = string_sprintf("%s@%s",
2691 local_part_quote(authenticated_id), submission_domain);
2692 }
2693 }
2694 else
2695 generated_sender_address = string_sprintf("%s@%s",
2696 local_part_quote(originator_login), qualify_domain_sender);
2697
2698 /* Remove permitted prefixes and suffixes from the local part of the From:
2699 address before doing the comparison with the generated sender. */
2700
2701 if (from_address != NULL)
2702 {
2703 int slen;
2704 uschar *at = (domain == 0)? NULL : from_address + domain - 1;
2705
2706 if (at != NULL) *at = 0;
2707 from_address += route_check_prefix(from_address, local_from_prefix);
2708 slen = route_check_suffix(from_address, local_from_suffix);
2709 if (slen > 0)
2710 {
2711 memmove(from_address+slen, from_address, Ustrlen(from_address)-slen);
2712 from_address += slen;
2713 }
2714 if (at != NULL) *at = '@';
2715
2716 if (strcmpic(generated_sender_address, from_address) == 0 ||
2717 (domain == 0 && strcmpic(from_address, originator_login) == 0))
2718 make_sender = FALSE;
2719 }
2720
2721 /* We have to cause the Sender header to be rewritten if there are
2722 appropriate rewriting rules. */
2723
2724 if (make_sender)
2725 {
2726 if (submission_mode && submission_name == NULL)
2727 header_add(htype_sender, "%sSender: %s\n", resent_prefix,
2728 generated_sender_address);
2729 else
2730 header_add(htype_sender, "%sSender: %s <%s>\n",
2731 resent_prefix,
2732 submission_mode? submission_name : originator_name,
2733 generated_sender_address);
2734 }
2735
2736 /* Ensure that a non-null envelope sender address corresponds to the
2737 submission mode sender address. */
2738
2739 if (submission_mode && sender_address[0] != 0)
2740 {
2741 if (sender_address_unrewritten == NULL)
2742 sender_address_unrewritten = sender_address;
2743 sender_address = generated_sender_address;
2744 if (Ustrcmp(sender_address_unrewritten, generated_sender_address) != 0)
2745 log_write(L_address_rewrite, LOG_MAIN,
2746 "\"%s\" from env-from rewritten as \"%s\" by submission mode",
2747 sender_address_unrewritten, generated_sender_address);
2748 }
2749 }
2750
2751 /* If there are any rewriting rules, apply them to the sender address, unless
2752 it has already been rewritten as part of verification for SMTP input. */
2753
2754 if (global_rewrite_rules != NULL && sender_address_unrewritten == NULL &&
2755 sender_address[0] != 0)
2756 {
2757 sender_address = rewrite_address(sender_address, FALSE, TRUE,
2758 global_rewrite_rules, rewrite_existflags);
2759 DEBUG(D_receive|D_rewrite)
2760 debug_printf("rewritten sender = %s\n", sender_address);
2761 }
2762
2763
2764 /* The headers must be run through rewrite_header(), because it ensures that
2765 addresses are fully qualified, as well as applying any rewriting rules that may
2766 exist.
2767
2768 Qualification of header addresses in a message from a remote host happens only
2769 if the host is in sender_unqualified_hosts or recipient_unqualified hosts, as
2770 appropriate. For local messages, qualification always happens, unless -bnq is
2771 used to explicitly suppress it. No rewriting is done for an unqualified address
2772 that is left untouched.
2773
2774 We start at the second header, skipping our own Received:. This rewriting is
2775 documented as happening *after* recipient addresses are taken from the headers
2776 by the -t command line option. An added Sender: gets rewritten here. */
2777
2778 for (h = header_list->next; h != NULL; h = h->next)
2779 {
2780 header_line *newh = rewrite_header(h, NULL, NULL, global_rewrite_rules,
2781 rewrite_existflags, TRUE);
2782 if (newh != NULL) h = newh;
2783 }
2784
2785
2786 /* An RFC 822 (sic) message is not legal unless it has at least one of "to",
2787 "cc", or "bcc". Note that although the minimal examples in RFC 822 show just
2788 "to" or "bcc", the full syntax spec allows "cc" as well. If any resent- header
2789 exists, this applies to the set of resent- headers rather than the normal set.
2790
2791 The requirement for a recipient header has been removed in RFC 2822. At this
2792 point in the code, earlier versions of Exim added a To: header for locally
2793 submitted messages, and an empty Bcc: header for others. In the light of the
2794 changes in RFC 2822, this was dropped in November 2003. */
2795
2796
2797 /* If there is no date header, generate one if the message originates locally
2798 (i.e. not over TCP/IP) and suppress_local_fixups is not set, or if the
2799 submission mode flag is set. Messages without Date: are not valid, but it seems
2800 to be more confusing if Exim adds one to all remotely-originated messages.
2801 As per Message-Id, we prepend if resending, else append.
2802 */
2803
2804 if (!date_header_exists &&
2805 ((sender_host_address == NULL && !suppress_local_fixups)
2806 || submission_mode))
2807 header_add_at_position(!resents_exist, NULL, FALSE, htype_other,
2808 "%sDate: %s\n", resent_prefix, tod_stamp(tod_full));
2809
2810 search_tidyup(); /* Free any cached resources */
2811
2812 /* Show the complete set of headers if debugging. Note that the first one (the
2813 new Received:) has not yet been set. */
2814
2815 DEBUG(D_receive)
2816 {
2817 debug_printf(">>Headers after rewriting and local additions:\n");
2818 for (h = header_list->next; h != NULL; h = h->next)
2819 debug_printf("%c %s", h->type, h->text);
2820 debug_printf("\n");
2821 }
2822
2823 /* The headers are now complete in store. If we are running in filter
2824 testing mode, that is all this function does. Return TRUE if the message
2825 ended with a dot. */
2826
2827 if (filter_test != FTEST_NONE)
2828 {
2829 process_info[process_info_len] = 0;
2830 return message_ended == END_DOT;
2831 }
2832
2833 /* Cutthrough delivery:
2834 We have to create the Received header now rather than at the end of reception,
2835 so the timestamp behaviour is a change to the normal case.
2836 XXX Ensure this gets documented XXX.
2837 Having created it, send the headers to the destination. */
2838 if (cutthrough.fd >= 0)
2839 {
2840 if (received_count > received_headers_max)
2841 {
2842 cancel_cutthrough_connection("too many headers");
2843 if (smtp_input) receive_swallow_smtp(); /* Swallow incoming SMTP */
2844 log_write(0, LOG_MAIN|LOG_REJECT, "rejected from <%s>%s%s%s%s: "
2845 "Too many \"Received\" headers",
2846 sender_address,
2847 (sender_fullhost == NULL)? "" : " H=",
2848 (sender_fullhost == NULL)? US"" : sender_fullhost,
2849 (sender_ident == NULL)? "" : " U=",
2850 (sender_ident == NULL)? US"" : sender_ident);
2851 message_id[0] = 0; /* Indicate no message accepted */
2852 smtp_reply = US"550 Too many \"Received\" headers - suspected mail loop";
2853 goto TIDYUP; /* Skip to end of function */
2854 }
2855 received_header_gen();
2856 add_acl_headers(ACL_WHERE_RCPT, US"MAIL or RCPT");
2857 (void) cutthrough_headers_send();
2858 }
2859
2860
2861 /* Open a new spool file for the data portion of the message. We need
2862 to access it both via a file descriptor and a stream. Try to make the
2863 directory if it isn't there. Note re use of sprintf: spool_directory
2864 is checked on input to be < 200 characters long. */
2865
2866 sprintf(CS spool_name, "%s/input/%s/%s-D", spool_directory, message_subdir,
2867 message_id);
2868 data_fd = Uopen(spool_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
2869 if (data_fd < 0)
2870 {
2871 if (errno == ENOENT)
2872 {
2873 uschar temp[16];
2874 sprintf(CS temp, "input/%s", message_subdir);
2875 if (message_subdir[0] == 0) temp[5] = 0;
2876 (void)directory_make(spool_directory, temp, INPUT_DIRECTORY_MODE, TRUE);
2877 data_fd = Uopen(spool_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
2878 }
2879 if (data_fd < 0)
2880 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Failed to create spool file %s: %s",
2881 spool_name, strerror(errno));
2882 }
2883
2884 /* Make sure the file's group is the Exim gid, and double-check the mode
2885 because the group setting doesn't always get set automatically. */
2886
2887 if (fchown(data_fd, exim_uid, exim_gid))
2888 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
2889 "Failed setting ownership on spool file %s: %s",
2890 spool_name, strerror(errno));
2891 (void)fchmod(data_fd, SPOOL_MODE);
2892
2893 /* We now have data file open. Build a stream for it and lock it. We lock only
2894 the first line of the file (containing the message ID) because otherwise there
2895 are problems when Exim is run under Cygwin (I'm told). See comments in
2896 spool_in.c, where the same locking is done. */
2897
2898 data_file = fdopen(data_fd, "w+");
2899 lock_data.l_type = F_WRLCK;
2900 lock_data.l_whence = SEEK_SET;
2901 lock_data.l_start = 0;
2902 lock_data.l_len = SPOOL_DATA_START_OFFSET;
2903
2904 if (fcntl(data_fd, F_SETLK, &lock_data) < 0)
2905 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Cannot lock %s (%d): %s", spool_name,
2906 errno, strerror(errno));
2907
2908 /* We have an open, locked data file. Write the message id to it to make it
2909 self-identifying. Then read the remainder of the input of this message and
2910 write it to the data file. If the variable next != NULL, it contains the first
2911 data line (which was read as a header but then turned out not to have the right
2912 format); write it (remembering that it might contain binary zeros). The result
2913 of fwrite() isn't inspected; instead we call ferror() below. */
2914
2915 fprintf(data_file, "%s-D\n", message_id);
2916 if (next != NULL)
2917 {
2918 uschar *s = next->text;
2919 int len = next->slen;
2920 len = fwrite(s, 1, len, data_file); len = len; /* compiler quietening */
2921 body_linecount++; /* Assumes only 1 line */
2922 }
2923
2924 /* Note that we might already be at end of file, or the logical end of file
2925 (indicated by '.'), or might have encountered an error while writing the
2926 message id or "next" line. */
2927
2928 if (!ferror(data_file) && !(receive_feof)() && message_ended != END_DOT)
2929 {
2930 if (smtp_input)
2931 {
2932 message_ended = read_message_data_smtp(data_file);
2933 receive_linecount++; /* The terminating "." line */
2934 }
2935 else message_ended = read_message_data(data_file);
2936
2937 receive_linecount += body_linecount; /* For BSMTP errors mainly */
2938 message_linecount += body_linecount;
2939
2940 /* Handle premature termination of SMTP */
2941
2942 if (smtp_input && message_ended == END_EOF)
2943 {
2944 Uunlink(spool_name); /* Lose data file when closed */
2945 cancel_cutthrough_connection("sender closed connection");
2946 message_id[0] = 0; /* Indicate no message accepted */
2947 smtp_reply = handle_lost_connection(US"");
2948 smtp_yield = FALSE;
2949 goto TIDYUP; /* Skip to end of function */
2950 }
2951
2952 /* Handle message that is too big. Don't use host_or_ident() in the log
2953 message; we want to see the ident value even for non-remote messages. */
2954
2955 if (message_ended == END_SIZE)
2956 {
2957 Uunlink(spool_name); /* Lose the data file when closed */
2958 cancel_cutthrough_connection("mail too big");
2959 if (smtp_input) receive_swallow_smtp(); /* Swallow incoming SMTP */
2960
2961 log_write(L_size_reject, LOG_MAIN|LOG_REJECT, "rejected from <%s>%s%s%s%s: "
2962 "message too big: read=%d max=%d",
2963 sender_address,
2964 (sender_fullhost == NULL)? "" : " H=",
2965 (sender_fullhost == NULL)? US"" : sender_fullhost,
2966 (sender_ident == NULL)? "" : " U=",
2967 (sender_ident == NULL)? US"" : sender_ident,
2968 message_size,
2969 thismessage_size_limit);
2970
2971 if (smtp_input)
2972 {
2973 smtp_reply = US"552 Message size exceeds maximum permitted";
2974 message_id[0] = 0; /* Indicate no message accepted */
2975 goto TIDYUP; /* Skip to end of function */
2976 }
2977 else
2978 {
2979 fseek(data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
2980 give_local_error(ERRMESS_TOOBIG,
2981 string_sprintf("message too big (max=%d)", thismessage_size_limit),
2982 US"message rejected: ", error_rc, data_file, header_list);
2983 /* Does not return */
2984 }
2985 }
2986 }
2987
2988 /* Restore the standard SIGALRM handler for any subsequent processing. (For
2989 example, there may be some expansion in an ACL that uses a timer.) */
2990
2991 os_non_restarting_signal(SIGALRM, sigalrm_handler);
2992
2993 /* The message body has now been read into the data file. Call fflush() to
2994 empty the buffers in C, and then call fsync() to get the data written out onto
2995 the disk, as fflush() doesn't do this (or at least, it isn't documented as
2996 having to do this). If there was an I/O error on either input or output,
2997 attempt to send an error message, and unlink the spool file. For non-SMTP input
2998 we can then give up. Note that for SMTP input we must swallow the remainder of
2999 the input in cases of output errors, since the far end doesn't expect to see
3000 anything until the terminating dot line is sent. */
3001
3002 if (fflush(data_file) == EOF || ferror(data_file) ||
3003 EXIMfsync(fileno(data_file)) < 0 || (receive_ferror)())
3004 {
3005 uschar *msg_errno = US strerror(errno);
3006 BOOL input_error = (receive_ferror)() != 0;
3007 uschar *msg = string_sprintf("%s error (%s) while receiving message from %s",
3008 input_error? "Input read" : "Spool write",
3009 msg_errno,
3010 (sender_fullhost != NULL)? sender_fullhost : sender_ident);
3011
3012 log_write(0, LOG_MAIN, "Message abandoned: %s", msg);
3013 Uunlink(spool_name); /* Lose the data file */
3014 cancel_cutthrough_connection("error writing spoolfile");
3015
3016 if (smtp_input)
3017 {
3018 if (input_error)
3019 smtp_reply = US"451 Error while reading input data";
3020 else
3021 {
3022 smtp_reply = US"451 Error while writing spool file";
3023 receive_swallow_smtp();
3024 }
3025 message_id[0] = 0; /* Indicate no message accepted */
3026 goto TIDYUP; /* Skip to end of function */
3027 }
3028
3029 else
3030 {
3031 fseek(data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3032 give_local_error(ERRMESS_IOERR, msg, US"", error_rc, data_file,
3033 header_list);
3034 /* Does not return */
3035 }
3036 }
3037
3038
3039 /* No I/O errors were encountered while writing the data file. */
3040
3041 DEBUG(D_receive) debug_printf("Data file written for message %s\n", message_id);
3042
3043
3044 /* If there were any bad addresses extracted by -t, or there were no recipients
3045 left after -t, send a message to the sender of this message, or write it to
3046 stderr if the error handling option is set that way. Note that there may
3047 legitimately be no recipients for an SMTP message if they have all been removed
3048 by "discard".
3049
3050 We need to rewind the data file in order to read it. In the case of no
3051 recipients or stderr error writing, throw the data file away afterwards, and
3052 exit. (This can't be SMTP, which always ensures there's at least one
3053 syntactically good recipient address.) */
3054
3055 if (extract_recip && (bad_addresses != NULL || recipients_count == 0))
3056 {
3057 DEBUG(D_receive)
3058 {
3059 if (recipients_count == 0) debug_printf("*** No recipients\n");
3060 if (bad_addresses != NULL)
3061 {
3062 error_block *eblock = bad_addresses;
3063 debug_printf("*** Bad address(es)\n");
3064 while (eblock != NULL)
3065 {
3066 debug_printf(" %s: %s\n", eblock->text1, eblock->text2);
3067 eblock = eblock->next;
3068 }
3069 }
3070 }
3071
3072 fseek(data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3073
3074 /* If configured to send errors to the sender, but this fails, force
3075 a failure error code. We use a special one for no recipients so that it
3076 can be detected by the autoreply transport. Otherwise error_rc is set to
3077 errors_sender_rc, which is EXIT_FAILURE unless -oee was given, in which case
3078 it is EXIT_SUCCESS. */
3079
3080 if (error_handling == ERRORS_SENDER)
3081 {
3082 if (!moan_to_sender(
3083 (bad_addresses == NULL)?
3084 (extracted_ignored? ERRMESS_IGADDRESS : ERRMESS_NOADDRESS) :
3085 (recipients_list == NULL)? ERRMESS_BADNOADDRESS : ERRMESS_BADADDRESS,
3086 bad_addresses, header_list, data_file, FALSE))
3087 error_rc = (bad_addresses == NULL)? EXIT_NORECIPIENTS : EXIT_FAILURE;
3088 }
3089 else
3090 {
3091 if (bad_addresses == NULL)
3092 {
3093 if (extracted_ignored)
3094 fprintf(stderr, "exim: all -t recipients overridden by command line\n");
3095 else
3096 fprintf(stderr, "exim: no recipients in message\n");
3097 }
3098 else
3099 {
3100 fprintf(stderr, "exim: invalid address%s",
3101 (bad_addresses->next == NULL)? ":" : "es:\n");
3102 while (bad_addresses != NULL)
3103 {
3104 fprintf(stderr, " %s: %s\n", bad_addresses->text1,
3105 bad_addresses->text2);
3106 bad_addresses = bad_addresses->next;
3107 }
3108 }
3109 }
3110
3111 if (recipients_count == 0 || error_handling == ERRORS_STDERR)
3112 {
3113 Uunlink(spool_name);
3114 (void)fclose(data_file);
3115 exim_exit(error_rc);
3116 }
3117 }
3118
3119 /* Data file successfully written. Generate text for the Received: header by
3120 expanding the configured string, and adding a timestamp. By leaving this
3121 operation till now, we ensure that the timestamp is the time that message
3122 reception was completed. However, this is deliberately done before calling the
3123 data ACL and local_scan().
3124
3125 This Received: header may therefore be inspected by the data ACL and by code in
3126 the local_scan() function. When they have run, we update the timestamp to be
3127 the final time of reception.
3128
3129 If there is just one recipient, set up its value in the $received_for variable
3130 for use when we generate the Received: header.
3131
3132 Note: the checking for too many Received: headers is handled by the delivery
3133 code. */
3134 /*XXX eventually add excess Received: check for cutthrough case back when classifying them */
3135
3136 if (received_header->text == NULL) /* Non-cutthrough case */
3137 {
3138 received_header_gen();
3139
3140 /* Set the value of message_body_size for the DATA ACL and for local_scan() */
3141
3142 message_body_size = (fstat(data_fd, &statbuf) == 0)?
3143 statbuf.st_size - SPOOL_DATA_START_OFFSET : -1;
3144
3145 /* If an ACL from any RCPT commands set up any warning headers to add, do so
3146 now, before running the DATA ACL. */
3147
3148 add_acl_headers(ACL_WHERE_RCPT, US"MAIL or RCPT");
3149 }
3150 else
3151 message_body_size = (fstat(data_fd, &statbuf) == 0)?
3152 statbuf.st_size - SPOOL_DATA_START_OFFSET : -1;
3153
3154 /* If an ACL is specified for checking things at this stage of reception of a
3155 message, run it, unless all the recipients were removed by "discard" in earlier
3156 ACLs. That is the only case in which recipients_count can be zero at this
3157 stage. Set deliver_datafile to point to the data file so that $message_body and
3158 $message_body_end can be extracted if needed. Allow $recipients in expansions.
3159 */
3160
3161 deliver_datafile = data_fd;
3162 user_msg = NULL;
3163
3164 enable_dollar_recipients = TRUE;
3165
3166 if (recipients_count == 0)
3167 {
3168 blackholed_by = recipients_discarded? US"MAIL ACL" : US"RCPT ACL";
3169 }
3170 else
3171 {
3172 /* Handle interactive SMTP messages */
3173
3174 if (smtp_input && !smtp_batched_input)
3175 {
3176
3177 #ifndef DISABLE_DKIM
3178 if (!dkim_disable_verify)
3179 {
3180 /* Finish verification, this will log individual signature results to
3181 the mainlog */
3182 dkim_exim_verify_finish();
3183
3184 /* Check if we must run the DKIM ACL */
3185 if ((acl_smtp_dkim != NULL) &&
3186 (dkim_verify_signers != NULL) &&
3187 (dkim_verify_signers[0] != '\0'))
3188 {
3189 uschar *dkim_verify_signers_expanded =
3190 expand_string(dkim_verify_signers);
3191 if (dkim_verify_signers_expanded == NULL)
3192 {
3193 log_write(0, LOG_MAIN|LOG_PANIC,
3194 "expansion of dkim_verify_signers option failed: %s",
3195 expand_string_message);
3196 }
3197 else
3198 {
3199 int sep = 0;
3200 const uschar *ptr = dkim_verify_signers_expanded;
3201 uschar *item = NULL;
3202 uschar *seen_items = NULL;
3203 int seen_items_size = 0;
3204 int seen_items_offset = 0;
3205 uschar itembuf[256];
3206 /* Default to OK when no items are present */
3207 rc = OK;
3208 while ((item = string_nextinlist(&ptr, &sep,
3209 itembuf,
3210 sizeof(itembuf))))
3211 {
3212 /* Prevent running ACL for an empty item */
3213 if (!item || (item[0] == '\0')) continue;
3214
3215 /* Only run ACL once for each domain or identity,
3216 no matter how often it appears in the expanded list. */
3217 if (seen_items)
3218 {
3219 uschar *seen_item = NULL;
3220 uschar seen_item_buf[256];
3221 const uschar *seen_items_list = seen_items;
3222 BOOL seen_this_item = FALSE;
3223
3224 while ((seen_item = string_nextinlist(&seen_items_list, &sep,
3225 seen_item_buf,
3226 sizeof(seen_item_buf))))
3227 if (Ustrcmp(seen_item,item) == 0)
3228 {
3229 seen_this_item = TRUE;
3230 break;
3231 }
3232
3233 if (seen_this_item)
3234 {
3235 DEBUG(D_receive)
3236 debug_printf("acl_smtp_dkim: skipping signer %s, "
3237 "already seen\n", item);
3238 continue;
3239 }
3240
3241 seen_items = string_append(seen_items, &seen_items_size,
3242 &seen_items_offset, 1, ":");
3243 }
3244
3245 seen_items = string_append(seen_items, &seen_items_size,
3246 &seen_items_offset, 1, item);
3247 seen_items[seen_items_offset] = '\0';
3248
3249 DEBUG(D_receive)
3250 debug_printf("calling acl_smtp_dkim for dkim_cur_signer=%s\n",
3251 item);
3252
3253 dkim_exim_acl_setup(item);
3254 rc = acl_check(ACL_WHERE_DKIM, NULL, acl_smtp_dkim,
3255 &user_msg, &log_msg);
3256
3257 if (rc != OK)
3258 {
3259 DEBUG(D_receive)
3260 debug_printf("acl_smtp_dkim: acl_check returned %d on %s, "
3261 "skipping remaining items\n", rc, item);
3262 cancel_cutthrough_connection("dkim acl not ok");
3263 break;
3264 }
3265 }
3266 add_acl_headers(ACL_WHERE_DKIM, US"DKIM");
3267 if (rc == DISCARD)
3268 {
3269 recipients_count = 0;
3270 blackholed_by = US"DKIM ACL";
3271 if (log_msg != NULL)
3272 blackhole_log_msg = string_sprintf(": %s", log_msg);
3273 }
3274 else if (rc != OK)
3275 {
3276 Uunlink(spool_name);
3277 if (smtp_handle_acl_fail(ACL_WHERE_DKIM, rc, user_msg, log_msg) != 0)
3278 smtp_yield = FALSE; /* No more messages after dropped connection */
3279 smtp_reply = US""; /* Indicate reply already sent */
3280 message_id[0] = 0; /* Indicate no message accepted */
3281 goto TIDYUP; /* Skip to end of function */
3282 }
3283 }
3284 }
3285 }
3286 #endif /* DISABLE_DKIM */
3287
3288 #ifdef WITH_CONTENT_SCAN
3289 if (recipients_count > 0 &&
3290 acl_smtp_mime != NULL &&
3291 !run_mime_acl(acl_smtp_mime, &smtp_yield, &smtp_reply, &blackholed_by))
3292 goto TIDYUP;
3293 #endif /* WITH_CONTENT_SCAN */
3294
3295 #ifdef EXPERIMENTAL_DMARC
3296 dmarc_up = dmarc_store_data(from_header);
3297 #endif /* EXPERIMENTAL_DMARC */
3298
3299 #ifndef DISABLE_PRDR
3300 if (prdr_requested && recipients_count > 1 && acl_smtp_data_prdr)
3301 {
3302 unsigned int c;
3303 int all_pass = OK;
3304 int all_fail = FAIL;
3305
3306 smtp_printf("353 PRDR content analysis beginning\r\n");
3307 /* Loop through recipients, responses must be in same order received */
3308 for (c = 0; recipients_count > c; c++)
3309 {
3310 uschar * addr= recipients_list[c].address;
3311 uschar * msg= US"PRDR R=<%s> %s";
3312 uschar * code;
3313 DEBUG(D_receive)
3314 debug_printf("PRDR processing recipient %s (%d of %d)\n",
3315 addr, c+1, recipients_count);
3316 rc = acl_check(ACL_WHERE_PRDR, addr,
3317 acl_smtp_data_prdr, &user_msg, &log_msg);
3318
3319 /* If any recipient rejected content, indicate it in final message */
3320 all_pass |= rc;
3321 /* If all recipients rejected, indicate in final message */
3322 all_fail &= rc;
3323
3324 switch (rc)
3325 {
3326 case OK: case DISCARD: code = US"250"; break;
3327 case DEFER: code = US"450"; break;
3328 default: code = US"550"; break;
3329 }
3330 if (user_msg != NULL)
3331 smtp_user_msg(code, user_msg);
3332 else
3333 {
3334 switch (rc)
3335 {
3336 case OK: case DISCARD:
3337 msg = string_sprintf(CS msg, addr, "acceptance"); break;
3338 case DEFER:
3339 msg = string_sprintf(CS msg, addr, "temporary refusal"); break;
3340 default:
3341 msg = string_sprintf(CS msg, addr, "refusal"); break;
3342 }
3343 smtp_user_msg(code, msg);
3344 }
3345 if (log_msg) log_write(0, LOG_MAIN, "PRDR %s %s", addr, log_msg);
3346 else if (user_msg) log_write(0, LOG_MAIN, "PRDR %s %s", addr, user_msg);
3347 else log_write(0, LOG_MAIN, "%s", CS msg);
3348
3349 if (rc != OK) { receive_remove_recipient(addr); c--; }
3350 }
3351 /* Set up final message, used if data acl gives OK */
3352 smtp_reply = string_sprintf("%s id=%s message %s",
3353 all_fail == FAIL ? US"550" : US"250",
3354 message_id,
3355 all_fail == FAIL
3356 ? US"rejected for all recipients"
3357 : all_pass == OK
3358 ? US"accepted"
3359 : US"accepted for some recipients");
3360 if (recipients_count == 0)
3361 {
3362 message_id[0] = 0; /* Indicate no message accepted */
3363 goto TIDYUP;
3364 }
3365 }
3366 else
3367 prdr_requested = FALSE;
3368 #endif /* !DISABLE_PRDR */
3369
3370 /* Check the recipients count again, as the MIME ACL might have changed
3371 them. */
3372
3373 if (acl_smtp_data != NULL && recipients_count > 0)
3374 {
3375 rc = acl_check(ACL_WHERE_DATA, NULL, acl_smtp_data, &user_msg, &log_msg);
3376 add_acl_headers(ACL_WHERE_DATA, US"DATA");
3377 if (rc == DISCARD)
3378 {
3379 recipients_count = 0;
3380 blackholed_by = US"DATA ACL";
3381 if (log_msg != NULL)
3382 blackhole_log_msg = string_sprintf(": %s", log_msg);
3383 cancel_cutthrough_connection("data acl discard");
3384 }
3385 else if (rc != OK)
3386 {
3387 Uunlink(spool_name);
3388 cancel_cutthrough_connection("data acl not ok");
3389 #ifdef WITH_CONTENT_SCAN
3390 unspool_mbox();
3391 #endif
3392 #ifdef EXPERIMENTAL_DCC
3393 dcc_ok = 0;
3394 #endif
3395 if (smtp_handle_acl_fail(ACL_WHERE_DATA, rc, user_msg, log_msg) != 0)
3396 smtp_yield = FALSE; /* No more messages after dropped connection */
3397 smtp_reply = US""; /* Indicate reply already sent */
3398 message_id[0] = 0; /* Indicate no message accepted */
3399 goto TIDYUP; /* Skip to end of function */
3400 }
3401 }
3402 }
3403
3404 /* Handle non-SMTP and batch SMTP (i.e. non-interactive) messages. Note that
3405 we cannot take different actions for permanent and temporary rejections. */
3406
3407 else
3408 {
3409
3410 #ifdef WITH_CONTENT_SCAN
3411 if (acl_not_smtp_mime != NULL &&
3412 !run_mime_acl(acl_not_smtp_mime, &smtp_yield, &smtp_reply,
3413 &blackholed_by))
3414 goto TIDYUP;
3415 #endif /* WITH_CONTENT_SCAN */
3416
3417 if (acl_not_smtp != NULL)
3418 {
3419 uschar *user_msg, *log_msg;
3420 rc = acl_check(ACL_WHERE_NOTSMTP, NULL, acl_not_smtp, &user_msg, &log_msg);
3421 if (rc == DISCARD)
3422 {
3423 recipients_count = 0;
3424 blackholed_by = US"non-SMTP ACL";
3425 if (log_msg != NULL)
3426 blackhole_log_msg = string_sprintf(": %s", log_msg);
3427 }
3428 else if (rc != OK)
3429 {
3430 Uunlink(spool_name);
3431 #ifdef WITH_CONTENT_SCAN
3432 unspool_mbox();
3433 #endif
3434 #ifdef EXPERIMENTAL_DCC
3435 dcc_ok = 0;
3436 #endif
3437 /* The ACL can specify where rejections are to be logged, possibly
3438 nowhere. The default is main and reject logs. */
3439
3440 if (log_reject_target != 0)
3441 log_write(0, log_reject_target, "F=<%s> rejected by non-SMTP ACL: %s",
3442 sender_address, log_msg);
3443
3444 if (user_msg == NULL) user_msg = US"local configuration problem";
3445 if (smtp_batched_input)
3446 {
3447 moan_smtp_batch(NULL, "%d %s", 550, user_msg);
3448 /* Does not return */
3449 }
3450 else
3451 {
3452 fseek(data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3453 give_local_error(ERRMESS_LOCAL_ACL, user_msg,
3454 US"message rejected by non-SMTP ACL: ", error_rc, data_file,
3455 header_list);
3456 /* Does not return */
3457 }
3458 }
3459 add_acl_headers(ACL_WHERE_NOTSMTP, US"non-SMTP");
3460 }
3461 }
3462
3463 /* The applicable ACLs have been run */
3464
3465 if (deliver_freeze) frozen_by = US"ACL"; /* for later logging */
3466 if (queue_only_policy) queued_by = US"ACL";
3467 }
3468
3469 #ifdef WITH_CONTENT_SCAN
3470 unspool_mbox();
3471 #endif
3472
3473 #ifdef EXPERIMENTAL_DCC
3474 dcc_ok = 0;
3475 #endif
3476
3477
3478 /* The final check on the message is to run the scan_local() function. The
3479 version supplied with Exim always accepts, but this is a hook for sysadmins to
3480 supply their own checking code. The local_scan() function is run even when all
3481 the recipients have been discarded. */
3482
3483 lseek(data_fd, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3484
3485 /* Arrange to catch crashes in local_scan(), so that the -D file gets
3486 deleted, and the incident gets logged. */
3487
3488 os_non_restarting_signal(SIGSEGV, local_scan_crash_handler);
3489 os_non_restarting_signal(SIGFPE, local_scan_crash_handler);
3490 os_non_restarting_signal(SIGILL, local_scan_crash_handler);
3491 os_non_restarting_signal(SIGBUS, local_scan_crash_handler);
3492
3493 DEBUG(D_receive) debug_printf("calling local_scan(); timeout=%d\n",
3494 local_scan_timeout);
3495 local_scan_data = NULL;
3496
3497 os_non_restarting_signal(SIGALRM, local_scan_timeout_handler);
3498 if (local_scan_timeout > 0) alarm(local_scan_timeout);
3499 rc = local_scan(data_fd, &local_scan_data);
3500 alarm(0);
3501 os_non_restarting_signal(SIGALRM, sigalrm_handler);
3502
3503 enable_dollar_recipients = FALSE;
3504
3505 store_pool = POOL_MAIN; /* In case changed */
3506 DEBUG(D_receive) debug_printf("local_scan() returned %d %s\n", rc,
3507 local_scan_data);
3508
3509 os_non_restarting_signal(SIGSEGV, SIG_DFL);
3510 os_non_restarting_signal(SIGFPE, SIG_DFL);
3511 os_non_restarting_signal(SIGILL, SIG_DFL);
3512 os_non_restarting_signal(SIGBUS, SIG_DFL);
3513
3514 /* The length check is paranoia against some runaway code, and also because
3515 (for a success return) lines in the spool file are read into big_buffer. */
3516
3517 if (local_scan_data != NULL)
3518 {
3519 int len = Ustrlen(local_scan_data);
3520 if (len > LOCAL_SCAN_MAX_RETURN) len = LOCAL_SCAN_MAX_RETURN;
3521 local_scan_data = string_copyn(local_scan_data, len);
3522 }
3523
3524 if (rc == LOCAL_SCAN_ACCEPT_FREEZE)
3525 {
3526 if (!deliver_freeze) /* ACL might have already frozen */
3527 {
3528 deliver_freeze = TRUE;
3529 deliver_frozen_at = time(NULL);
3530 frozen_by = US"local_scan()";
3531 }
3532 rc = LOCAL_SCAN_ACCEPT;
3533 }
3534 else if (rc == LOCAL_SCAN_ACCEPT_QUEUE)
3535 {
3536 if (!queue_only_policy) /* ACL might have already queued */
3537 {
3538 queue_only_policy = TRUE;
3539 queued_by = US"local_scan()";
3540 }
3541 rc = LOCAL_SCAN_ACCEPT;
3542 }
3543
3544 /* Message accepted: remove newlines in local_scan_data because otherwise
3545 the spool file gets corrupted. Ensure that all recipients are qualified. */
3546
3547 if (rc == LOCAL_SCAN_ACCEPT)
3548 {
3549 if (local_scan_data != NULL)
3550 {
3551 uschar *s;
3552 for (s = local_scan_data; *s != 0; s++) if (*s == '\n') *s = ' ';
3553 }
3554 for (i = 0; i < recipients_count; i++)
3555 {
3556 recipient_item *r = recipients_list + i;
3557 r->address = rewrite_address_qualify(r->address, TRUE);
3558 if (r->errors_to != NULL)
3559 r->errors_to = rewrite_address_qualify(r->errors_to, TRUE);
3560 }
3561 if (recipients_count == 0 && blackholed_by == NULL)
3562 blackholed_by = US"local_scan";
3563 }
3564
3565 /* Message rejected: newlines permitted in local_scan_data to generate
3566 multiline SMTP responses. */
3567
3568 else
3569 {
3570 uschar *istemp = US"";
3571 uschar *s = NULL;
3572 uschar *smtp_code;
3573 int size = 0;
3574 int sptr = 0;
3575
3576 errmsg = local_scan_data;
3577
3578 Uunlink(spool_name); /* Cancel this message */
3579 switch(rc)
3580 {
3581 default:
3582 log_write(0, LOG_MAIN, "invalid return %d from local_scan(). Temporary "
3583 "rejection given", rc);
3584 goto TEMPREJECT;
3585
3586 case LOCAL_SCAN_REJECT_NOLOGHDR:
3587 BIT_CLEAR(log_selector, log_selector_size, Li_rejected_header);
3588 /* Fall through */
3589
3590 case LOCAL_SCAN_REJECT:
3591 smtp_code = US"550";
3592 if (errmsg == NULL) errmsg = US"Administrative prohibition";
3593 break;
3594
3595 case LOCAL_SCAN_TEMPREJECT_NOLOGHDR:
3596 BIT_CLEAR(log_selector, log_selector_size, Li_rejected_header);
3597 /* Fall through */
3598
3599 case LOCAL_SCAN_TEMPREJECT:
3600 TEMPREJECT:
3601 smtp_code = US"451";
3602 if (errmsg == NULL) errmsg = US"Temporary local problem";
3603 istemp = US"temporarily ";
3604 break;
3605 }
3606
3607 s = string_append(s, &size, &sptr, 2, US"F=",
3608 (sender_address[0] == 0)? US"<>" : sender_address);
3609 s = add_host_info_for_log(s, &size, &sptr);
3610 s[sptr] = 0;
3611
3612 log_write(0, LOG_MAIN|LOG_REJECT, "%s %srejected by local_scan(): %.256s",
3613 s, istemp, string_printing(errmsg));
3614
3615 if (smtp_input)
3616 {
3617 if (!smtp_batched_input)
3618 {
3619 smtp_respond(smtp_code, 3, TRUE, errmsg);
3620 message_id[0] = 0; /* Indicate no message accepted */
3621 smtp_reply = US""; /* Indicate reply already sent */
3622 goto TIDYUP; /* Skip to end of function */
3623 }
3624 else
3625 {
3626 moan_smtp_batch(NULL, "%s %s", smtp_code, errmsg);
3627 /* Does not return */
3628 }
3629 }
3630 else
3631 {
3632 fseek(data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3633 give_local_error(ERRMESS_LOCAL_SCAN, errmsg,
3634 US"message rejected by local scan code: ", error_rc, data_file,
3635 header_list);
3636 /* Does not return */
3637 }
3638 }
3639
3640 /* Reset signal handlers to ignore signals that previously would have caused
3641 the message to be abandoned. */
3642
3643 signal(SIGTERM, SIG_IGN);
3644 signal(SIGINT, SIG_IGN);
3645
3646
3647 /* Ensure the first time flag is set in the newly-received message. */
3648
3649 deliver_firsttime = TRUE;
3650
3651 #ifdef EXPERIMENTAL_BRIGHTMAIL
3652 if (bmi_run == 1) {
3653 /* rewind data file */
3654 lseek(data_fd, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3655 bmi_verdicts = bmi_process_message(header_list, data_fd);
3656 };
3657 #endif
3658
3659 /* Update the timstamp in our Received: header to account for any time taken by
3660 an ACL or by local_scan(). The new time is the time that all reception
3661 processing is complete. */
3662
3663 timestamp = expand_string(US"${tod_full}");
3664 tslen = Ustrlen(timestamp);
3665
3666 memcpy(received_header->text + received_header->slen - tslen - 1,
3667 timestamp, tslen);
3668
3669 /* In MUA wrapper mode, ignore queueing actions set by ACL or local_scan() */
3670
3671 if (mua_wrapper)
3672 {
3673 deliver_freeze = FALSE;
3674 queue_only_policy = FALSE;
3675 }
3676
3677 /* Keep the data file open until we have written the header file, in order to
3678 hold onto the lock. In a -bh run, or if the message is to be blackholed, we
3679 don't write the header file, and we unlink the data file. If writing the header
3680 file fails, we have failed to accept this message. */
3681
3682 if (host_checking || blackholed_by != NULL)
3683 {
3684 header_line *h;
3685 Uunlink(spool_name);
3686 msg_size = 0; /* Compute size for log line */
3687 for (h = header_list; h != NULL; h = h->next)
3688 if (h->type != '*') msg_size += h->slen;
3689 }
3690
3691 /* Write the -H file */
3692
3693 else
3694 {
3695 if ((msg_size = spool_write_header(message_id, SW_RECEIVING, &errmsg)) < 0)
3696 {
3697 log_write(0, LOG_MAIN, "Message abandoned: %s", errmsg);
3698 Uunlink(spool_name); /* Lose the data file */
3699
3700 if (smtp_input)
3701 {
3702 smtp_reply = US"451 Error in writing spool file";
3703 message_id[0] = 0; /* Indicate no message accepted */
3704 goto TIDYUP;
3705 }
3706 else
3707 {
3708 fseek(data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3709 give_local_error(ERRMESS_IOERR, errmsg, US"", error_rc, data_file,
3710 header_list);
3711 /* Does not return */
3712 }
3713 }
3714 }
3715
3716
3717 /* The message has now been successfully received. */
3718
3719 receive_messagecount++;
3720
3721 /* In SMTP sessions we may receive several in one connection. After each one,
3722 we wait for the clock to tick at the level of message-id granularity. This is
3723 so that the combination of time+pid is unique, even on systems where the pid
3724 can be re-used within our time interval. We can't shorten the interval without
3725 re-designing the message-id. See comments above where the message id is
3726 created. This is Something For The Future. */
3727
3728 message_id_tv.tv_usec = (message_id_tv.tv_usec/id_resolution) * id_resolution;
3729 exim_wait_tick(&message_id_tv, id_resolution);
3730
3731 /* Add data size to written header size. We do not count the initial file name
3732 that is in the file, but we do add one extra for the notional blank line that
3733 precedes the data. This total differs from message_size in that it include the
3734 added Received: header and any other headers that got created locally. */
3735
3736 fflush(data_file);
3737 fstat(data_fd, &statbuf);
3738
3739 msg_size += statbuf.st_size - SPOOL_DATA_START_OFFSET + 1;
3740
3741 /* Generate a "message received" log entry. We do this by building up a dynamic
3742 string as required. Since we commonly want to add two items at a time, use a
3743 macro to simplify the coding. We log the arrival of a new message while the
3744 file is still locked, just in case the machine is *really* fast, and delivers
3745 it first! Include any message id that is in the message - since the syntax of a
3746 message id is actually an addr-spec, we can use the parse routine to canonicize
3747 it. */
3748
3749 size = 256;
3750 sptr = 0;
3751 s = store_get(size);
3752
3753 s = string_append(s, &size, &sptr, 2, US"<= ",
3754 (sender_address[0] == 0)? US"<>" : sender_address);
3755 if (message_reference != NULL)
3756 s = string_append(s, &size, &sptr, 2, US" R=", message_reference);
3757
3758 s = add_host_info_for_log(s, &size, &sptr);
3759
3760 #ifdef SUPPORT_TLS
3761 if (LOGGING(tls_cipher) && tls_in.cipher)
3762 s = string_append(s, &size, &sptr, 2, US" X=", tls_in.cipher);
3763 if (LOGGING(tls_certificate_verified) && tls_in.cipher)
3764 s = string_append(s, &size, &sptr, 2, US" CV=",
3765 tls_in.certificate_verified? "yes":"no");
3766 if (LOGGING(tls_peerdn) && tls_in.peerdn)
3767 s = string_append(s, &size, &sptr, 3, US" DN=\"",
3768 string_printing(tls_in.peerdn), US"\"");
3769 if (LOGGING(tls_sni) && tls_in.sni)
3770 s = string_append(s, &size, &sptr, 3, US" SNI=\"",
3771 string_printing(tls_in.sni), US"\"");
3772 #endif
3773
3774 if (sender_host_authenticated)
3775 {
3776 s = string_append(s, &size, &sptr, 2, US" A=", sender_host_authenticated);
3777 if (authenticated_id != NULL)
3778 {
3779 s = string_append(s, &size, &sptr, 2, US":", authenticated_id);
3780 if (LOGGING(smtp_mailauth) && authenticated_sender != NULL)
3781 s = string_append(s, &size, &sptr, 2, US":", authenticated_sender);
3782 }
3783 }
3784
3785 #ifndef DISABLE_PRDR
3786 if (prdr_requested)
3787 s = string_append(s, &size, &sptr, 1, US" PRDR");
3788 #endif
3789
3790 #ifdef SUPPORT_PROXY
3791 if (proxy_session && LOGGING(proxy))
3792 s = string_append(s, &size, &sptr, 2, US" PRX=", proxy_local_address);
3793 #endif
3794
3795 sprintf(CS big_buffer, "%d", msg_size);
3796 s = string_append(s, &size, &sptr, 2, US" S=", big_buffer);
3797
3798 /* log 8BITMIME mode announced in MAIL_FROM
3799 0 ... no BODY= used
3800 7 ... 7BIT
3801 8 ... 8BITMIME */
3802 if (LOGGING(8bitmime))
3803 {
3804 sprintf(CS big_buffer, "%d", body_8bitmime);
3805 s = string_append(s, &size, &sptr, 2, US" M8S=", big_buffer);
3806 }
3807
3808 /* If an addr-spec in a message-id contains a quoted string, it can contain
3809 any characters except " \ and CR and so in particular it can contain NL!
3810 Therefore, make sure we use a printing-characters only version for the log.
3811 Also, allow for domain literals in the message id. */
3812
3813 if (msgid_header != NULL)
3814 {
3815 uschar *old_id;
3816 BOOL save_allow_domain_literals = allow_domain_literals;
3817 allow_domain_literals = TRUE;
3818 old_id = parse_extract_address(Ustrchr(msgid_header->text, ':') + 1,
3819 &errmsg, &start, &end, &domain, FALSE);
3820 allow_domain_literals = save_allow_domain_literals;
3821 if (old_id != NULL)
3822 s = string_append(s, &size, &sptr, 2, US" id=", string_printing(old_id));
3823 }
3824
3825 /* If subject logging is turned on, create suitable printing-character
3826 text. By expanding $h_subject: we make use of the MIME decoding. */
3827
3828 if (LOGGING(subject) && subject_header != NULL)
3829 {
3830 int i;
3831 uschar *p = big_buffer;
3832 uschar *ss = expand_string(US"$h_subject:");
3833
3834 /* Backslash-quote any double quotes or backslashes so as to make a
3835 a C-like string, and turn any non-printers into escape sequences. */
3836
3837 *p++ = '\"';
3838 if (*ss != 0) for (i = 0; i < 100 && ss[i] != 0; i++)
3839 {
3840 if (ss[i] == '\"' || ss[i] == '\\') *p++ = '\\';
3841 *p++ = ss[i];
3842 }
3843 *p++ = '\"';
3844 *p = 0;
3845 s = string_append(s, &size, &sptr, 2, US" T=", string_printing(big_buffer));
3846 }
3847
3848 /* Terminate the string: string_cat() and string_append() leave room, but do
3849 not put the zero in. */
3850
3851 s[sptr] = 0;
3852
3853 /* Create a message log file if message logs are being used and this message is
3854 not blackholed. Write the reception stuff to it. We used to leave message log
3855 creation until the first delivery, but this has proved confusing for some
3856 people. */
3857
3858 if (message_logs && blackholed_by == NULL)
3859 {
3860 int fd;
3861
3862 sprintf(CS spool_name, "%s/msglog/%s/%s", spool_directory, message_subdir,
3863 message_id);
3864 fd = Uopen(spool_name, O_WRONLY|O_APPEND|O_CREAT, SPOOL_MODE);
3865
3866 if (fd < 0 && errno == ENOENT)
3867 {
3868 uschar temp[16];
3869 sprintf(CS temp, "msglog/%s", message_subdir);
3870 if (message_subdir[0] == 0) temp[6] = 0;
3871 (void)directory_make(spool_directory, temp, MSGLOG_DIRECTORY_MODE, TRUE);
3872 fd = Uopen(spool_name, O_WRONLY|O_APPEND|O_CREAT, SPOOL_MODE);
3873 }
3874
3875 if (fd < 0)
3876 {
3877 log_write(0, LOG_MAIN|LOG_PANIC, "Couldn't open message log %s: %s",
3878 spool_name, strerror(errno));
3879 }
3880
3881 else
3882 {
3883 FILE *message_log = fdopen(fd, "a");
3884 if (message_log == NULL)
3885 {
3886 log_write(0, LOG_MAIN|LOG_PANIC, "Couldn't fdopen message log %s: %s",
3887 spool_name, strerror(errno));
3888 (void)close(fd);
3889 }
3890 else
3891 {
3892 uschar *now = tod_stamp(tod_log);
3893 fprintf(message_log, "%s Received from %s\n", now, s+3);
3894 if (deliver_freeze) fprintf(message_log, "%s frozen by %s\n", now,
3895 frozen_by);
3896 if (queue_only_policy) fprintf(message_log,
3897 "%s no immediate delivery: queued by %s\n", now, queued_by);
3898 (void)fclose(message_log);
3899 }
3900 }
3901 }
3902
3903 /* Everything has now been done for a successful message except logging its
3904 arrival, and outputting an SMTP response. While writing to the log, set a flag
3905 to cause a call to receive_bomb_out() if the log cannot be opened. */
3906
3907 receive_call_bombout = TRUE;
3908
3909 /* Before sending an SMTP response in a TCP/IP session, we check to see if the
3910 connection has gone away. This can only be done if there is no unconsumed input
3911 waiting in the local input buffer. We can test for this by calling
3912 receive_smtp_buffered(). RFC 2920 (pipelining) explicitly allows for additional
3913 input to be sent following the final dot, so the presence of following input is
3914 not an error.
3915
3916 If the connection is still present, but there is no unread input for the
3917 socket, the result of a select() call will be zero. If, however, the connection
3918 has gone away, or if there is pending input, the result of select() will be
3919 non-zero. The two cases can be distinguished by trying to read the next input
3920 character. If we succeed, we can unread it so that it remains in the local
3921 buffer for handling later. If not, the connection has been lost.
3922
3923 Of course, since TCP/IP is asynchronous, there is always a chance that the
3924 connection will vanish between the time of this test and the sending of the
3925 response, but the chance of this happening should be small. */
3926
3927 if (smtp_input && sender_host_address != NULL && !sender_host_notsocket &&
3928 !receive_smtp_buffered())
3929 {
3930 struct timeval tv;
3931 fd_set select_check;
3932 FD_ZERO(&select_check);
3933 FD_SET(fileno(smtp_in), &select_check);
3934 tv.tv_sec = 0;
3935 tv.tv_usec = 0;
3936
3937 if (select(fileno(smtp_in) + 1, &select_check, NULL, NULL, &tv) != 0)
3938 {
3939 int c = (receive_getc)();
3940 if (c != EOF) (receive_ungetc)(c); else
3941 {
3942 uschar *msg = US"SMTP connection lost after final dot";
3943 smtp_reply = US""; /* No attempt to send a response */
3944 smtp_yield = FALSE; /* Nothing more on this connection */
3945
3946 /* Re-use the log line workspace */
3947
3948 sptr = 0;
3949 s = string_cat(s, &size, &sptr, msg);
3950 s = add_host_info_for_log(s, &size, &sptr);
3951 s[sptr] = 0;
3952 log_write(0, LOG_MAIN, "%s", s);
3953
3954 /* Delete the files for this aborted message. */
3955
3956 sprintf(CS spool_name, "%s/input/%s/%s-D", spool_directory,
3957 message_subdir, message_id);
3958 Uunlink(spool_name);
3959
3960 sprintf(CS spool_name, "%s/input/%s/%s-H", spool_directory,
3961 message_subdir, message_id);
3962 Uunlink(spool_name);
3963
3964 sprintf(CS spool_name, "%s/msglog/%s/%s", spool_directory,
3965 message_subdir, message_id);
3966 Uunlink(spool_name);
3967
3968 goto TIDYUP;
3969 }
3970 }
3971 }
3972
3973 /* The connection has not gone away; we really are going to take responsibility
3974 for this message. */
3975
3976 /* Cutthrough - had sender last-dot; assume we've sent (or bufferred) all
3977 data onward by now.
3978
3979 Send dot onward. If accepted, wipe the spooled files, log as delivered and accept
3980 the sender's dot (below).
3981 If rejected: copy response to sender, wipe the spooled files, log approriately.
3982 If temp-reject: accept to sender, keep the spooled files.
3983
3984 Having the normal spool files lets us do data-filtering, and store/forward on temp-reject.
3985
3986 XXX We do not handle queue-only, freezing, or blackholes.
3987 */
3988 if(cutthrough.fd >= 0)
3989 {
3990 uschar * msg= cutthrough_finaldot(); /* Ask the target system to accept the message */
3991 /* Logging was done in finaldot() */
3992 switch(msg[0])
3993 {
3994 case '2': /* Accept. Do the same to the source; dump any spoolfiles. */
3995 cutthrough_done = ACCEPTED;
3996 break; /* message_id needed for SMTP accept below */
3997
3998 default: /* Unknown response, or error. Treat as temp-reject. */
3999 case '4': /* Temp-reject. Keep spoolfiles and accept. */
4000 cutthrough_done = TMP_REJ; /* Avoid the usual immediate delivery attempt */
4001 break; /* message_id needed for SMTP accept below */
4002
4003 case '5': /* Perm-reject. Do the same to the source. Dump any spoolfiles */
4004 smtp_reply= msg; /* Pass on the exact error */
4005 cutthrough_done = PERM_REJ;
4006 break;
4007 }
4008 }
4009
4010 #ifndef DISABLE_PRDR
4011 if(!smtp_reply || prdr_requested)
4012 #else
4013 if(!smtp_reply)
4014 #endif
4015 {
4016 log_write(0, LOG_MAIN |
4017 (LOGGING(received_recipients)? LOG_RECIPIENTS : 0) |
4018 (LOGGING(received_sender)? LOG_SENDER : 0),
4019 "%s", s);
4020
4021 /* Log any control actions taken by an ACL or local_scan(). */
4022
4023 if (deliver_freeze) log_write(0, LOG_MAIN, "frozen by %s", frozen_by);
4024 if (queue_only_policy) log_write(L_delay_delivery, LOG_MAIN,
4025 "no immediate delivery: queued by %s", queued_by);
4026 }
4027 receive_call_bombout = FALSE;
4028
4029 store_reset(s); /* The store for the main log message can be reused */
4030
4031 /* If the message is frozen, and freeze_tell is set, do the telling. */
4032
4033 if (deliver_freeze && freeze_tell != NULL && freeze_tell[0] != 0)
4034 {
4035 moan_tell_someone(freeze_tell, NULL, US"Message frozen on arrival",
4036 "Message %s was frozen on arrival by %s.\nThe sender is <%s>.\n",
4037 message_id, frozen_by, sender_address);
4038 }
4039
4040
4041 /* Either a message has been successfully received and written to the two spool
4042 files, or an error in writing the spool has occurred for an SMTP message, or
4043 an SMTP message has been rejected for policy reasons. (For a non-SMTP message
4044 we will have already given up because there's no point in carrying on!) In
4045 either event, we must now close (and thereby unlock) the data file. In the
4046 successful case, this leaves the message on the spool, ready for delivery. In
4047 the error case, the spool file will be deleted. Then tidy up store, interact
4048 with an SMTP call if necessary, and return.
4049
4050 A fflush() was done earlier in the expectation that any write errors on the
4051 data file will be flushed(!) out thereby. Nevertheless, it is theoretically
4052 possible for fclose() to fail - but what to do? What has happened to the lock
4053 if this happens? */
4054
4055
4056 TIDYUP:
4057 process_info[process_info_len] = 0; /* Remove message id */
4058 if (data_file != NULL) (void)fclose(data_file); /* Frees the lock */
4059
4060 /* Now reset signal handlers to their defaults */
4061
4062 signal(SIGTERM, SIG_DFL);
4063 signal(SIGINT, SIG_DFL);
4064
4065 /* Tell an SMTP caller the state of play, and arrange to return the SMTP return
4066 value, which defaults TRUE - meaning there may be more incoming messages from
4067 this connection. For non-SMTP callers (where there is only ever one message),
4068 the default is FALSE. */
4069