e9877d3a0441207f017086dd93976e9fbd40b876
[exim.git] / src / src / receive.c
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
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 #include <setjmp.h>
12
13 #ifdef EXPERIMENTAL_DCC
14 extern int dcc_ok;
15 #endif
16
17 #ifdef EXPERIMENTAL_DMARC
18 # include "dmarc.h"
19 #endif /* EXPERIMENTAL_DMARC */
20
21 /*************************************************
22 * Local static variables *
23 *************************************************/
24
25 static int data_fd = -1;
26 static uschar *spool_name = US"";
27
28 enum CH_STATE {LF_SEEN, MID_LINE, CR_SEEN};
29
30 #ifdef HAVE_LOCAL_SCAN
31 jmp_buf local_scan_env; /* error-handling context for local_scan */
32 unsigned had_local_scan_crash;
33 unsigned had_local_scan_timeout;
34 #endif
35
36
37 /*************************************************
38 * Non-SMTP character reading functions *
39 *************************************************/
40
41 /* These are the default functions that are set up in the variables such as
42 receive_getc initially. They just call the standard functions, passing stdin as
43 the file. (When SMTP input is occurring, different functions are used by
44 changing the pointer variables.) */
45
46 int
47 stdin_getc(unsigned lim)
48 {
49 int c = getc(stdin);
50
51 if (had_data_timeout)
52 {
53 fprintf(stderr, "exim: timed out while reading - message abandoned\n");
54 log_write(L_lost_incoming_connection,
55 LOG_MAIN, "timed out while reading local message");
56 receive_bomb_out(US"data-timeout", NULL); /* Does not return */
57 }
58 if (had_data_sigint)
59 {
60 if (filter_test == FTEST_NONE)
61 {
62 fprintf(stderr, "\nexim: %s received - message abandoned\n",
63 had_data_sigint == SIGTERM ? "SIGTERM" : "SIGINT");
64 log_write(0, LOG_MAIN, "%s received while reading local message",
65 had_data_sigint == SIGTERM ? "SIGTERM" : "SIGINT");
66 }
67 receive_bomb_out(US"signal-exit", NULL); /* Does not return */
68 }
69 return c;
70 }
71
72 int
73 stdin_ungetc(int c)
74 {
75 return ungetc(c, stdin);
76 }
77
78 int
79 stdin_feof(void)
80 {
81 return feof(stdin);
82 }
83
84 int
85 stdin_ferror(void)
86 {
87 return ferror(stdin);
88 }
89
90
91
92
93 /*************************************************
94 * Check that a set sender is allowed *
95 *************************************************/
96
97 /* This function is called when a local caller sets an explicit sender address.
98 It checks whether this is permitted, which it is for trusted callers.
99 Otherwise, it must match the pattern(s) in untrusted_set_sender.
100
101 Arguments: the proposed sender address
102 Returns: TRUE for a trusted caller
103 TRUE if the address has been set, untrusted_set_sender has been
104 set, and the address matches something in the list
105 FALSE otherwise
106 */
107
108 BOOL
109 receive_check_set_sender(uschar *newsender)
110 {
111 uschar *qnewsender;
112 if (f.trusted_caller) return TRUE;
113 if (!newsender || !untrusted_set_sender) return FALSE;
114 qnewsender = Ustrchr(newsender, '@')
115 ? newsender : string_sprintf("%s@%s", newsender, qualify_domain_sender);
116 return match_address_list_basic(qnewsender, CUSS &untrusted_set_sender, 0) == OK;
117 }
118
119
120
121
122 /*************************************************
123 * Read space info for a partition *
124 *************************************************/
125
126 /* This function is called by receive_check_fs() below, and also by string
127 expansion for variables such as $spool_space. The field names for the statvfs
128 structure are macros, because not all OS have F_FAVAIL and it seems tidier to
129 have macros for F_BAVAIL and F_FILES as well. Some kinds of file system do not
130 have inodes, and they return -1 for the number available.
131
132 Later: It turns out that some file systems that do not have the concept of
133 inodes return 0 rather than -1. Such systems should also return 0 for the total
134 number of inodes, so we require that to be greater than zero before returning
135 an inode count.
136
137 Arguments:
138 isspool TRUE for spool partition, FALSE for log partition
139 inodeptr address of int to receive inode count; -1 if there isn't one
140
141 Returns: available on-root space, in kilobytes
142 -1 for log partition if there isn't one
143
144 All values are -1 if the STATFS functions are not available.
145 */
146
147 int_eximarith_t
148 receive_statvfs(BOOL isspool, int *inodeptr)
149 {
150 #ifdef HAVE_STATFS
151 struct STATVFS statbuf;
152 struct stat dummy;
153 uschar *path;
154 uschar *name;
155 uschar buffer[1024];
156
157 /* The spool directory must always exist. */
158
159 if (isspool)
160 {
161 path = spool_directory;
162 name = US"spool";
163 }
164
165 /* Need to cut down the log file path to the directory, and to ignore any
166 appearance of "syslog" in it. */
167
168 else
169 {
170 int sep = ':'; /* Not variable - outside scripts use */
171 const uschar *p = log_file_path;
172 name = US"log";
173
174 /* An empty log_file_path means "use the default". This is the same as an
175 empty item in a list. */
176
177 if (*p == 0) p = US":";
178 while ((path = string_nextinlist(&p, &sep, buffer, sizeof(buffer))))
179 if (Ustrcmp(path, "syslog") != 0)
180 break;
181
182 if (path == NULL) /* No log files */
183 {
184 *inodeptr = -1;
185 return -1;
186 }
187
188 /* An empty string means use the default, which is in the spool directory.
189 But don't just use the spool directory, as it is possible that the log
190 subdirectory has been symbolically linked elsewhere. */
191
192 if (path[0] == 0)
193 {
194 sprintf(CS buffer, CS"%s/log", CS spool_directory);
195 path = buffer;
196 }
197 else
198 {
199 uschar *cp;
200 if ((cp = Ustrrchr(path, '/')) != NULL) *cp = 0;
201 }
202 }
203
204 /* We now have the path; do the business */
205
206 memset(&statbuf, 0, sizeof(statbuf));
207
208 if (STATVFS(CS path, &statbuf) != 0)
209 if (stat(CS path, &dummy) == -1 && errno == ENOENT)
210 { /* Can happen on first run after installation */
211 *inodeptr = -1;
212 return -1;
213 }
214 else
215 {
216 log_write(0, LOG_MAIN|LOG_PANIC, "cannot accept message: failed to stat "
217 "%s directory %s: %s", name, path, strerror(errno));
218 smtp_closedown(US"spool or log directory problem");
219 exim_exit(EXIT_FAILURE, NULL);
220 }
221
222 *inodeptr = (statbuf.F_FILES > 0)? statbuf.F_FAVAIL : -1;
223
224 /* Disks are getting huge. Take care with computing the size in kilobytes. */
225
226 return (int_eximarith_t)(((double)statbuf.F_BAVAIL * (double)statbuf.F_FRSIZE)/1024.0);
227
228 #else
229 /* Unable to find partition sizes in this environment. */
230
231 *inodeptr = -1;
232 return -1;
233 #endif
234 }
235
236
237
238
239 /*************************************************
240 * Check space on spool and log partitions *
241 *************************************************/
242
243 /* This function is called before accepting a message; if any thresholds are
244 set, it checks them. If a message_size is supplied, it checks that there is
245 enough space for that size plus the threshold - i.e. that the message won't
246 reduce the space to the threshold. Not all OS have statvfs(); for those that
247 don't, this function always returns TRUE. For some OS the old function and
248 struct name statfs is used; that is handled by a macro, defined in exim.h.
249
250 Arguments:
251 msg_size the (estimated) size of an incoming message
252
253 Returns: FALSE if there isn't enough space, or if the information cannot
254 be obtained
255 TRUE if no check was done or there is enough space
256 */
257
258 BOOL
259 receive_check_fs(int msg_size)
260 {
261 int_eximarith_t space;
262 int inodes;
263
264 if (check_spool_space > 0 || msg_size > 0 || check_spool_inodes > 0)
265 {
266 space = receive_statvfs(TRUE, &inodes);
267
268 DEBUG(D_receive)
269 debug_printf("spool directory space = " PR_EXIM_ARITH "K inodes = %d "
270 "check_space = " PR_EXIM_ARITH "K inodes = %d msg_size = %d\n",
271 space, inodes, check_spool_space, check_spool_inodes, msg_size);
272
273 if ((space >= 0 && space < check_spool_space) ||
274 (inodes >= 0 && inodes < check_spool_inodes))
275 {
276 log_write(0, LOG_MAIN, "spool directory space check failed: space=%d "
277 "inodes=%d", space, inodes);
278 return FALSE;
279 }
280 }
281
282 if (check_log_space > 0 || check_log_inodes > 0)
283 {
284 space = receive_statvfs(FALSE, &inodes);
285
286 DEBUG(D_receive)
287 debug_printf("log directory space = " PR_EXIM_ARITH "K inodes = %d "
288 "check_space = " PR_EXIM_ARITH "K inodes = %d\n",
289 space, inodes, check_log_space, check_log_inodes);
290
291 if ( space >= 0 && space < check_log_space
292 || inodes >= 0 && inodes < check_log_inodes)
293 {
294 log_write(0, LOG_MAIN, "log directory space check failed: space=" PR_EXIM_ARITH
295 " inodes=%d", space, inodes);
296 return FALSE;
297 }
298 }
299
300 return TRUE;
301 }
302
303
304
305 /*************************************************
306 * Bomb out while reading a message *
307 *************************************************/
308
309 /* The common case of wanting to bomb out is if a SIGTERM or SIGINT is
310 received, or if there is a timeout. A rarer case might be if the log files are
311 screwed up and Exim can't open them to record a message's arrival. Handling
312 that case is done by setting a flag to cause the log functions to call this
313 function if there is an ultimate disaster. That is why it is globally
314 accessible.
315
316 Arguments:
317 reason text reason to pass to the not-quit ACL
318 msg default SMTP response to give if in an SMTP session
319 Returns: it doesn't
320 */
321
322 void
323 receive_bomb_out(uschar *reason, uschar *msg)
324 {
325 static BOOL already_bombing_out;
326 /* The smtp_notquit_exit() below can call ACLs which can trigger recursive
327 timeouts, if someone has something slow in their quit ACL. Since the only
328 things we should be doing are to close down cleanly ASAP, on the second
329 pass we also close down stuff that might be opened again, before bypassing
330 the ACL call and exiting. */
331
332 /* If spool_name is set, it contains the name of the data file that is being
333 written. Unlink it before closing so that it cannot be picked up by a delivery
334 process. Ensure that any header file is also removed. */
335
336 if (spool_name[0] != '\0')
337 {
338 Uunlink(spool_name);
339 spool_name[Ustrlen(spool_name) - 1] = 'H';
340 Uunlink(spool_name);
341 spool_name[0] = '\0';
342 }
343
344 /* Now close the file if it is open, either as a fd or a stream. */
345
346 if (spool_data_file)
347 {
348 (void)fclose(spool_data_file);
349 spool_data_file = NULL;
350 }
351 else if (data_fd >= 0)
352 {
353 (void)close(data_fd);
354 data_fd = -1;
355 }
356
357 /* Attempt to close down an SMTP connection tidily. For non-batched SMTP, call
358 smtp_notquit_exit(), which runs the NOTQUIT ACL, if present, and handles the
359 SMTP response. */
360
361 if (!already_bombing_out)
362 {
363 already_bombing_out = TRUE;
364 if (smtp_input)
365 {
366 if (smtp_batched_input)
367 moan_smtp_batch(NULL, "421 %s - message abandoned", msg); /* No return */
368 smtp_notquit_exit(reason, US"421", US"%s %s - closing connection.",
369 smtp_active_hostname, msg);
370 }
371 }
372
373 /* Exit from the program (non-BSMTP cases) */
374
375 exim_exit(EXIT_FAILURE, NULL);
376 }
377
378
379 /*************************************************
380 * Data read timeout *
381 *************************************************/
382
383 /* Handler function for timeouts that occur while reading the data that
384 comprises a message.
385
386 Argument: the signal number
387 Returns: nothing
388 */
389
390 static void
391 data_timeout_handler(int sig)
392 {
393 had_data_timeout = sig;
394 }
395
396
397
398 #ifdef HAVE_LOCAL_SCAN
399 /*************************************************
400 * local_scan() timeout *
401 *************************************************/
402
403 /* Handler function for timeouts that occur while running a local_scan()
404 function. Posix recommends against calling longjmp() from a signal-handler,
405 but the GCC manual says you can so we will, and trust that it's better than
406 calling probably non-signal-safe funxtions during logging from within the
407 handler, even with other compilers.
408
409 See also https://cwe.mitre.org/data/definitions/745.html which also lists
410 it as unsafe.
411
412 This is all because we have no control over what might be written for a
413 local-scan function, so cannot sprinkle had-signal checks after each
414 call-site. At least with the default "do-nothing" function we won't
415 ever get here.
416
417 Argument: the signal number
418 Returns: nothing
419 */
420
421 static void
422 local_scan_timeout_handler(int sig)
423 {
424 had_local_scan_timeout = sig;
425 siglongjmp(local_scan_env, 1);
426 }
427
428
429
430 /*************************************************
431 * local_scan() crashed *
432 *************************************************/
433
434 /* Handler function for signals that occur while running a local_scan()
435 function.
436
437 Argument: the signal number
438 Returns: nothing
439 */
440
441 static void
442 local_scan_crash_handler(int sig)
443 {
444 had_local_scan_crash = sig;
445 siglongjmp(local_scan_env, 1);
446 }
447
448 #endif /*HAVE_LOCAL_SCAN*/
449
450
451 /*************************************************
452 * SIGTERM or SIGINT received *
453 *************************************************/
454
455 /* Handler for SIGTERM or SIGINT signals that occur while reading the
456 data that comprises a message.
457
458 Argument: the signal number
459 Returns: nothing
460 */
461
462 static void
463 data_sigterm_sigint_handler(int sig)
464 {
465 had_data_sigint = sig;
466 }
467
468
469
470 /*************************************************
471 * Add new recipient to list *
472 *************************************************/
473
474 /* This function builds a list of recipient addresses in argc/argv
475 format.
476
477 Arguments:
478 recipient the next address to add to recipients_list
479 pno parent number for fixed aliases; -1 otherwise
480
481 Returns: nothing
482 */
483
484 void
485 receive_add_recipient(uschar *recipient, int pno)
486 {
487 if (recipients_count >= recipients_list_max)
488 {
489 recipient_item *oldlist = recipients_list;
490 int oldmax = recipients_list_max;
491 recipients_list_max = recipients_list_max ? 2*recipients_list_max : 50;
492 recipients_list = store_get(recipients_list_max * sizeof(recipient_item));
493 if (oldlist != NULL)
494 memcpy(recipients_list, oldlist, oldmax * sizeof(recipient_item));
495 }
496
497 recipients_list[recipients_count].address = recipient;
498 recipients_list[recipients_count].pno = pno;
499 #ifdef EXPERIMENTAL_BRIGHTMAIL
500 recipients_list[recipients_count].bmi_optin = bmi_current_optin;
501 /* reset optin string pointer for next recipient */
502 bmi_current_optin = NULL;
503 #endif
504 recipients_list[recipients_count].orcpt = NULL;
505 recipients_list[recipients_count].dsn_flags = 0;
506 recipients_list[recipients_count++].errors_to = NULL;
507 }
508
509
510
511
512 /*************************************************
513 * Send user response message *
514 *************************************************/
515
516 /* This function is passed a default response code and a user message. It calls
517 smtp_message_code() to check and possibly modify the response code, and then
518 calls smtp_respond() to transmit the response. I put this into a function
519 just to avoid a lot of repetition.
520
521 Arguments:
522 code the response code
523 user_msg the user message
524
525 Returns: nothing
526 */
527
528 #ifndef DISABLE_PRDR
529 static void
530 smtp_user_msg(uschar *code, uschar *user_msg)
531 {
532 int len = 3;
533 smtp_message_code(&code, &len, &user_msg, NULL, TRUE);
534 smtp_respond(code, len, TRUE, user_msg);
535 }
536 #endif
537
538
539
540
541
542 /*************************************************
543 * Remove a recipient from the list *
544 *************************************************/
545
546 /* This function is provided for local_scan() to use.
547
548 Argument:
549 recipient address to remove
550
551 Returns: TRUE if it did remove something; FALSE otherwise
552 */
553
554 BOOL
555 receive_remove_recipient(uschar *recipient)
556 {
557 int count;
558 DEBUG(D_receive) debug_printf("receive_remove_recipient(\"%s\") called\n",
559 recipient);
560 for (count = 0; count < recipients_count; count++)
561 {
562 if (Ustrcmp(recipients_list[count].address, recipient) == 0)
563 {
564 if ((--recipients_count - count) > 0)
565 memmove(recipients_list + count, recipients_list + count + 1,
566 (recipients_count - count)*sizeof(recipient_item));
567 return TRUE;
568 }
569 }
570 return FALSE;
571 }
572
573
574
575
576
577 /*************************************************
578 * Read data portion of a non-SMTP message *
579 *************************************************/
580
581 /* This function is called to read the remainder of a message (following the
582 header) when the input is not from SMTP - we are receiving a local message on
583 a standard input stream. The message is always terminated by EOF, and is also
584 terminated by a dot on a line by itself if the flag dot_ends is TRUE. Split the
585 two cases for maximum efficiency.
586
587 Ensure that the body ends with a newline. This will naturally be the case when
588 the termination is "\n.\n" but may not be otherwise. The RFC defines messages
589 as "sequences of lines" - this of course strictly applies only to SMTP, but
590 deliveries into BSD-type mailbox files also require it. Exim used to have a
591 flag for doing this at delivery time, but as it was always set for all
592 transports, I decided to simplify things by putting the check here instead.
593
594 There is at least one MUA (dtmail) that sends CRLF via this interface, and
595 other programs are known to do this as well. Exim used to have a option for
596 dealing with this: in July 2003, after much discussion, the code has been
597 changed to default to treat any of LF, CRLF, and bare CR as line terminators.
598
599 However, for the case when a dot on a line by itself terminates a message, the
600 only recognized terminating sequences before and after the dot are LF and CRLF.
601 Otherwise, having read EOL . CR, you don't know whether to read another
602 character or not.
603
604 Internally, in messages stored in Exim's spool files, LF is used as the line
605 terminator. Under the new regime, bare CRs will no longer appear in these
606 files.
607
608 Arguments:
609 fout a FILE to which to write the message
610
611 Returns: One of the END_xxx values indicating why it stopped reading
612 */
613
614 static int
615 read_message_data(FILE *fout)
616 {
617 int ch_state;
618 register int ch;
619 register int linelength = 0;
620
621 /* Handle the case when only EOF terminates the message */
622
623 if (!f.dot_ends)
624 {
625 register int last_ch = '\n';
626
627 for (; (ch = (receive_getc)(GETC_BUFFER_UNLIMITED)) != EOF; last_ch = ch)
628 {
629 if (ch == 0) body_zerocount++;
630 if (last_ch == '\r' && ch != '\n')
631 {
632 if (linelength > max_received_linelength)
633 max_received_linelength = linelength;
634 linelength = 0;
635 if (fputc('\n', fout) == EOF) return END_WERROR;
636 message_size++;
637 body_linecount++;
638 }
639 if (ch == '\r') continue;
640
641 if (fputc(ch, fout) == EOF) return END_WERROR;
642 if (ch == '\n')
643 {
644 if (linelength > max_received_linelength)
645 max_received_linelength = linelength;
646 linelength = 0;
647 body_linecount++;
648 }
649 else linelength++;
650 if (++message_size > thismessage_size_limit) return END_SIZE;
651 }
652
653 if (last_ch != '\n')
654 {
655 if (linelength > max_received_linelength)
656 max_received_linelength = linelength;
657 if (fputc('\n', fout) == EOF) return END_WERROR;
658 message_size++;
659 body_linecount++;
660 }
661
662 return END_EOF;
663 }
664
665 /* Handle the case when a dot on a line on its own, or EOF, terminates. */
666
667 ch_state = 1;
668
669 while ((ch = (receive_getc)(GETC_BUFFER_UNLIMITED)) != EOF)
670 {
671 if (ch == 0) body_zerocount++;
672 switch (ch_state)
673 {
674 case 0: /* Normal state (previous char written) */
675 if (ch == '\n')
676 {
677 body_linecount++;
678 if (linelength > max_received_linelength)
679 max_received_linelength = linelength;
680 linelength = -1;
681 ch_state = 1;
682 }
683 else if (ch == '\r')
684 { ch_state = 2; continue; }
685 break;
686
687 case 1: /* After written "\n" */
688 if (ch == '.') { ch_state = 3; continue; }
689 if (ch == '\r') { ch_state = 2; continue; }
690 if (ch == '\n') { body_linecount++; linelength = -1; }
691 else ch_state = 0;
692 break;
693
694 case 2:
695 body_linecount++; /* After unwritten "\r" */
696 if (linelength > max_received_linelength)
697 max_received_linelength = linelength;
698 if (ch == '\n')
699 {
700 ch_state = 1;
701 linelength = -1;
702 }
703 else
704 {
705 if (message_size++, fputc('\n', fout) == EOF) return END_WERROR;
706 if (ch == '\r') continue;
707 ch_state = 0;
708 linelength = 0;
709 }
710 break;
711
712 case 3: /* After "\n." (\n written, dot not) */
713 if (ch == '\n') return END_DOT;
714 if (ch == '\r') { ch_state = 4; continue; }
715 message_size++;
716 linelength++;
717 if (fputc('.', fout) == EOF) return END_WERROR;
718 ch_state = 0;
719 break;
720
721 case 4: /* After "\n.\r" (\n written, rest not) */
722 if (ch == '\n') return END_DOT;
723 message_size += 2;
724 body_linecount++;
725 if (fputs(".\n", fout) == EOF) return END_WERROR;
726 if (ch == '\r') { ch_state = 2; continue; }
727 ch_state = 0;
728 break;
729 }
730
731 linelength++;
732 if (fputc(ch, fout) == EOF) return END_WERROR;
733 if (++message_size > thismessage_size_limit) return END_SIZE;
734 }
735
736 /* Get here if EOF read. Unless we have just written "\n", we need to ensure
737 the message ends with a newline, and we must also write any characters that
738 were saved up while testing for an ending dot. */
739
740 if (ch_state != 1)
741 {
742 static uschar *ends[] = { US"\n", NULL, US"\n", US".\n", US".\n" };
743 if (fputs(CS ends[ch_state], fout) == EOF) return END_WERROR;
744 message_size += Ustrlen(ends[ch_state]);
745 body_linecount++;
746 }
747
748 return END_EOF;
749 }
750
751
752
753
754 /*************************************************
755 * Read data portion of an SMTP message *
756 *************************************************/
757
758 /* This function is called to read the remainder of an SMTP message (after the
759 headers), or to skip over it when an error has occurred. In this case, the
760 output file is passed as NULL.
761
762 If any line begins with a dot, that character is skipped. The input should only
763 be successfully terminated by CR LF . CR LF unless it is local (non-network)
764 SMTP, in which case the CRs are optional, but...
765
766 FUDGE: It seems that sites on the net send out messages with just LF
767 terminators, despite the warnings in the RFCs, and other MTAs handle this. So
768 we make the CRs optional in all cases.
769
770 July 2003: Bare CRs cause trouble. We now treat them as line terminators as
771 well, so that there are no CRs in spooled messages. However, the message
772 terminating dot is not recognized between two bare CRs.
773
774 Arguments:
775 fout a FILE to which to write the message; NULL if skipping
776
777 Returns: One of the END_xxx values indicating why it stopped reading
778 */
779
780 static int
781 read_message_data_smtp(FILE *fout)
782 {
783 int ch_state = 0;
784 int ch;
785 int linelength = 0;
786
787 while ((ch = (receive_getc)(GETC_BUFFER_UNLIMITED)) != EOF)
788 {
789 if (ch == 0) body_zerocount++;
790 switch (ch_state)
791 {
792 case 0: /* After LF or CRLF */
793 if (ch == '.')
794 {
795 ch_state = 3;
796 continue; /* Don't ever write . after LF */
797 }
798 ch_state = 1;
799
800 /* Else fall through to handle as normal uschar. */
801
802 case 1: /* Normal state */
803 if (ch == '\n')
804 {
805 ch_state = 0;
806 body_linecount++;
807 if (linelength > max_received_linelength)
808 max_received_linelength = linelength;
809 linelength = -1;
810 }
811 else if (ch == '\r')
812 {
813 ch_state = 2;
814 continue;
815 }
816 break;
817
818 case 2: /* After (unwritten) CR */
819 body_linecount++;
820 if (linelength > max_received_linelength)
821 max_received_linelength = linelength;
822 linelength = -1;
823 if (ch == '\n')
824 {
825 ch_state = 0;
826 }
827 else
828 {
829 message_size++;
830 if (fout != NULL && fputc('\n', fout) == EOF) return END_WERROR;
831 cutthrough_data_put_nl();
832 if (ch != '\r') ch_state = 1; else continue;
833 }
834 break;
835
836 case 3: /* After [CR] LF . */
837 if (ch == '\n')
838 return END_DOT;
839 if (ch == '\r')
840 {
841 ch_state = 4;
842 continue;
843 }
844 /* The dot was removed at state 3. For a doubled dot, here, reinstate
845 it to cutthrough. The current ch, dot or not, is passed both to cutthrough
846 and to file below. */
847 if (ch == '.')
848 {
849 uschar c= ch;
850 cutthrough_data_puts(&c, 1);
851 }
852 ch_state = 1;
853 break;
854
855 case 4: /* After [CR] LF . CR */
856 if (ch == '\n') return END_DOT;
857 message_size++;
858 body_linecount++;
859 if (fout != NULL && fputc('\n', fout) == EOF) return END_WERROR;
860 cutthrough_data_put_nl();
861 if (ch == '\r')
862 {
863 ch_state = 2;
864 continue;
865 }
866 ch_state = 1;
867 break;
868 }
869
870 /* Add the character to the spool file, unless skipping; then loop for the
871 next. */
872
873 message_size++;
874 linelength++;
875 if (fout)
876 {
877 if (fputc(ch, fout) == EOF) return END_WERROR;
878 if (message_size > thismessage_size_limit) return END_SIZE;
879 }
880 if(ch == '\n')
881 cutthrough_data_put_nl();
882 else
883 {
884 uschar c = ch;
885 cutthrough_data_puts(&c, 1);
886 }
887 }
888
889 /* Fall through here if EOF encountered. This indicates some kind of error,
890 since a correct message is terminated by [CR] LF . [CR] LF. */
891
892 return END_EOF;
893 }
894
895
896
897
898 /* Variant of the above read_message_data_smtp() specialised for RFC 3030
899 CHUNKING. Accept input lines separated by either CRLF or CR or LF and write
900 LF-delimited spoolfile. Until we have wireformat spoolfiles, we need the
901 body_linecount accounting for proper re-expansion for the wire, so use
902 a cut-down version of the state-machine above; we don't need to do leading-dot
903 detection and unstuffing.
904
905 Arguments:
906 fout a FILE to which to write the message; NULL if skipping;
907 must be open for both writing and reading.
908
909 Returns: One of the END_xxx values indicating why it stopped reading
910 */
911
912 static int
913 read_message_bdat_smtp(FILE *fout)
914 {
915 int linelength = 0, ch;
916 enum CH_STATE ch_state = LF_SEEN;
917 BOOL fix_nl = FALSE;
918
919 for(;;)
920 {
921 switch ((ch = bdat_getc(GETC_BUFFER_UNLIMITED)))
922 {
923 case EOF: return END_EOF;
924 case ERR: return END_PROTOCOL;
925 case EOD:
926 /* Nothing to get from the sender anymore. We check the last
927 character written to the spool.
928
929 RFC 3030 states, that BDAT chunks are normal text, terminated by CRLF.
930 If we would be strict, we would refuse such broken messages.
931 But we are liberal, so we fix it. It would be easy just to append
932 the "\n" to the spool.
933
934 But there are some more things (line counting, message size calculation and such),
935 that would need to be duplicated here. So we simply do some ungetc
936 trickery.
937 */
938 if (fout)
939 {
940 if (fseek(fout, -1, SEEK_CUR) < 0) return END_PROTOCOL;
941 if (fgetc(fout) == '\n') return END_DOT;
942 }
943
944 if (linelength == -1) /* \r already seen (see below) */
945 {
946 DEBUG(D_receive) debug_printf("Add missing LF\n");
947 bdat_ungetc('\n');
948 continue;
949 }
950 DEBUG(D_receive) debug_printf("Add missing CRLF\n");
951 bdat_ungetc('\r'); /* not even \r was seen */
952 fix_nl = TRUE;
953
954 continue;
955 case '\0': body_zerocount++; break;
956 }
957 switch (ch_state)
958 {
959 case LF_SEEN: /* After LF or CRLF */
960 ch_state = MID_LINE;
961 /* fall through to handle as normal uschar. */
962
963 case MID_LINE: /* Mid-line state */
964 if (ch == '\n')
965 {
966 ch_state = LF_SEEN;
967 body_linecount++;
968 if (linelength > max_received_linelength)
969 max_received_linelength = linelength;
970 linelength = -1;
971 }
972 else if (ch == '\r')
973 {
974 ch_state = CR_SEEN;
975 if (fix_nl) bdat_ungetc('\n');
976 continue; /* don't write CR */
977 }
978 break;
979
980 case CR_SEEN: /* After (unwritten) CR */
981 body_linecount++;
982 if (linelength > max_received_linelength)
983 max_received_linelength = linelength;
984 linelength = -1;
985 if (ch == '\n')
986 ch_state = LF_SEEN;
987 else
988 {
989 message_size++;
990 if (fout && fputc('\n', fout) == EOF) return END_WERROR;
991 cutthrough_data_put_nl();
992 if (ch == '\r') continue; /* don't write CR */
993 ch_state = MID_LINE;
994 }
995 break;
996 }
997
998 /* Add the character to the spool file, unless skipping */
999
1000 message_size++;
1001 linelength++;
1002 if (fout)
1003 {
1004 if (fputc(ch, fout) == EOF) return END_WERROR;
1005 if (message_size > thismessage_size_limit) return END_SIZE;
1006 }
1007 if(ch == '\n')
1008 cutthrough_data_put_nl();
1009 else
1010 {
1011 uschar c = ch;
1012 cutthrough_data_puts(&c, 1);
1013 }
1014 }
1015 /*NOTREACHED*/
1016 }
1017
1018 static int
1019 read_message_bdat_smtp_wire(FILE *fout)
1020 {
1021 int ch;
1022
1023 /* Remember that this message uses wireformat. */
1024
1025 DEBUG(D_receive) debug_printf("CHUNKING: %s\n",
1026 fout ? "writing spoolfile in wire format" : "flushing input");
1027 f.spool_file_wireformat = TRUE;
1028
1029 for (;;)
1030 {
1031 if (chunking_data_left > 0)
1032 {
1033 unsigned len = MAX(chunking_data_left, thismessage_size_limit - message_size + 1);
1034 uschar * buf = bdat_getbuf(&len);
1035
1036 if (!buf) return END_EOF;
1037 message_size += len;
1038 if (fout && fwrite(buf, len, 1, fout) != 1) return END_WERROR;
1039 }
1040 else switch (ch = bdat_getc(GETC_BUFFER_UNLIMITED))
1041 {
1042 case EOF: return END_EOF;
1043 case EOD: return END_DOT;
1044 case ERR: return END_PROTOCOL;
1045
1046 default:
1047 message_size++;
1048 /*XXX not done:
1049 linelength
1050 max_received_linelength
1051 body_linecount
1052 body_zerocount
1053 */
1054 if (fout && fputc(ch, fout) == EOF) return END_WERROR;
1055 break;
1056 }
1057 if (message_size > thismessage_size_limit) return END_SIZE;
1058 }
1059 /*NOTREACHED*/
1060 }
1061
1062
1063
1064
1065 /*************************************************
1066 * Swallow SMTP message *
1067 *************************************************/
1068
1069 /* This function is called when there has been some kind of error while reading
1070 an SMTP message, and the remaining data may need to be swallowed. It is global
1071 because it is called from smtp_closedown() to shut down an incoming call
1072 tidily.
1073
1074 Argument: a FILE from which to read the message
1075 Returns: nothing
1076 */
1077
1078 void
1079 receive_swallow_smtp(void)
1080 {
1081 if (message_ended >= END_NOTENDED)
1082 message_ended = chunking_state <= CHUNKING_OFFERED
1083 ? read_message_data_smtp(NULL)
1084 : read_message_bdat_smtp_wire(NULL);
1085 }
1086
1087
1088
1089 /*************************************************
1090 * Handle lost SMTP connection *
1091 *************************************************/
1092
1093 /* This function logs connection loss incidents and generates an appropriate
1094 SMTP response.
1095
1096 Argument: additional data for the message
1097 Returns: the SMTP response
1098 */
1099
1100 static uschar *
1101 handle_lost_connection(uschar *s)
1102 {
1103 log_write(L_lost_incoming_connection | L_smtp_connection, LOG_MAIN,
1104 "%s lost while reading message data%s", smtp_get_connection_info(), s);
1105 smtp_notquit_exit(US"connection-lost", NULL, NULL);
1106 return US"421 Lost incoming connection";
1107 }
1108
1109
1110
1111
1112 /*************************************************
1113 * Handle a non-smtp reception error *
1114 *************************************************/
1115
1116 /* This function is called for various errors during the reception of non-SMTP
1117 messages. It either sends a message to the sender of the problem message, or it
1118 writes to the standard error stream.
1119
1120 Arguments:
1121 errcode code for moan_to_sender(), identifying the error
1122 text1 first message text, passed to moan_to_sender()
1123 text2 second message text, used only for stderrr
1124 error_rc code to pass to exim_exit if no problem
1125 f FILE containing body of message (may be stdin)
1126 hptr pointer to instore headers or NULL
1127
1128 Returns: calls exim_exit(), which does not return
1129 */
1130
1131 static void
1132 give_local_error(int errcode, uschar *text1, uschar *text2, int error_rc,
1133 FILE *f, header_line *hptr)
1134 {
1135 if (error_handling == ERRORS_SENDER)
1136 {
1137 error_block eblock;
1138 eblock.next = NULL;
1139 eblock.text1 = text1;
1140 eblock.text2 = US"";
1141 if (!moan_to_sender(errcode, &eblock, hptr, f, FALSE))
1142 error_rc = EXIT_FAILURE;
1143 }
1144 else
1145 fprintf(stderr, "exim: %s%s\n", text2, text1); /* Sic */
1146 (void)fclose(f);
1147 exim_exit(error_rc, US"");
1148 }
1149
1150
1151
1152 /*************************************************
1153 * Add header lines set up by ACL *
1154 *************************************************/
1155
1156 /* This function is called to add the header lines that were set up by
1157 statements in an ACL to the list of headers in memory. It is done in two stages
1158 like this, because when the ACL for RCPT is running, the other headers have not
1159 yet been received. This function is called twice; once just before running the
1160 DATA ACL, and once after. This is so that header lines added by MAIL or RCPT
1161 are visible to the DATA ACL.
1162
1163 Originally these header lines were added at the end. Now there is support for
1164 three different places: top, bottom, and after the Received: header(s). There
1165 will always be at least one Received: header, even if it is marked deleted, and
1166 even if something else has been put in front of it.
1167
1168 Arguments:
1169 acl_name text to identify which ACL
1170
1171 Returns: nothing
1172 */
1173
1174 static void
1175 add_acl_headers(int where, uschar *acl_name)
1176 {
1177 header_line *h, *next;
1178 header_line *last_received = NULL;
1179
1180 switch(where)
1181 {
1182 case ACL_WHERE_DKIM:
1183 case ACL_WHERE_MIME:
1184 case ACL_WHERE_DATA:
1185 if ( cutthrough.cctx.sock >= 0 && cutthrough.delivery
1186 && (acl_removed_headers || acl_added_headers))
1187 {
1188 log_write(0, LOG_MAIN|LOG_PANIC, "Header modification in data ACLs"
1189 " will not take effect on cutthrough deliveries");
1190 return;
1191 }
1192 }
1193
1194 if (acl_removed_headers)
1195 {
1196 DEBUG(D_receive|D_acl) debug_printf_indent(">>Headers removed by %s ACL:\n", acl_name);
1197
1198 for (h = header_list; h; h = h->next) if (h->type != htype_old)
1199 {
1200 const uschar * list = acl_removed_headers;
1201 int sep = ':'; /* This is specified as a colon-separated list */
1202 uschar *s;
1203 uschar buffer[128];
1204
1205 while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer))))
1206 if (header_testname(h, s, Ustrlen(s), FALSE))
1207 {
1208 h->type = htype_old;
1209 DEBUG(D_receive|D_acl) debug_printf_indent(" %s", h->text);
1210 }
1211 }
1212 acl_removed_headers = NULL;
1213 DEBUG(D_receive|D_acl) debug_printf_indent(">>\n");
1214 }
1215
1216 if (!acl_added_headers) return;
1217 DEBUG(D_receive|D_acl) debug_printf_indent(">>Headers added by %s ACL:\n", acl_name);
1218
1219 for (h = acl_added_headers; h; h = next)
1220 {
1221 next = h->next;
1222
1223 switch(h->type)
1224 {
1225 case htype_add_top:
1226 h->next = header_list;
1227 header_list = h;
1228 DEBUG(D_receive|D_acl) debug_printf_indent(" (at top)");
1229 break;
1230
1231 case htype_add_rec:
1232 if (!last_received)
1233 {
1234 last_received = header_list;
1235 while (!header_testname(last_received, US"Received", 8, FALSE))
1236 last_received = last_received->next;
1237 while (last_received->next &&
1238 header_testname(last_received->next, US"Received", 8, FALSE))
1239 last_received = last_received->next;
1240 }
1241 h->next = last_received->next;
1242 last_received->next = h;
1243 DEBUG(D_receive|D_acl) debug_printf_indent(" (after Received:)");
1244 break;
1245
1246 case htype_add_rfc:
1247 /* add header before any header which is NOT Received: or Resent- */
1248 last_received = header_list;
1249 while ( last_received->next &&
1250 ( (header_testname(last_received->next, US"Received", 8, FALSE)) ||
1251 (header_testname_incomplete(last_received->next, US"Resent-", 7, FALSE)) ) )
1252 last_received = last_received->next;
1253 /* last_received now points to the last Received: or Resent-* header
1254 in an uninterrupted chain of those header types (seen from the beginning
1255 of all headers. Our current header must follow it. */
1256 h->next = last_received->next;
1257 last_received->next = h;
1258 DEBUG(D_receive|D_acl) debug_printf_indent(" (before any non-Received: or Resent-*: header)");
1259 break;
1260
1261 default:
1262 h->next = NULL;
1263 header_last->next = h;
1264 DEBUG(D_receive|D_acl) debug_printf_indent(" ");
1265 break;
1266 }
1267
1268 if (!h->next) header_last = h;
1269
1270 /* Check for one of the known header types (From:, To:, etc.) though in
1271 practice most added headers are going to be "other". Lower case
1272 identification letters are never stored with the header; they are used
1273 for existence tests when messages are received. So discard any lower case
1274 flag values. */
1275
1276 h->type = header_checkname(h, FALSE);
1277 if (h->type >= 'a') h->type = htype_other;
1278
1279 DEBUG(D_receive|D_acl) debug_printf("%s", h->text);
1280 }
1281
1282 acl_added_headers = NULL;
1283 DEBUG(D_receive|D_acl) debug_printf_indent(">>\n");
1284 }
1285
1286
1287
1288 /*************************************************
1289 * Add host information for log line *
1290 *************************************************/
1291
1292 /* Called for acceptance and rejecting log lines. This adds information about
1293 the calling host to a string that is being built dynamically.
1294
1295 Arguments:
1296 s the dynamic string
1297
1298 Returns: the extended string
1299 */
1300
1301 static gstring *
1302 add_host_info_for_log(gstring * g)
1303 {
1304 if (sender_fullhost)
1305 {
1306 if (LOGGING(dnssec) && sender_host_dnssec) /*XXX sender_helo_dnssec? */
1307 g = string_catn(g, US" DS", 3);
1308 g = string_append(g, 2, US" H=", sender_fullhost);
1309 if (LOGGING(incoming_interface) && interface_address)
1310 g = string_fmt_append(g, " I=[%s]:%d", interface_address, interface_port);
1311 }
1312 if (f.tcp_in_fastopen && !f.tcp_in_fastopen_logged)
1313 {
1314 g = string_catn(g, US" TFO*", f.tcp_in_fastopen_data ? 5 : 4);
1315 f.tcp_in_fastopen_logged = TRUE;
1316 }
1317 if (sender_ident)
1318 g = string_append(g, 2, US" U=", sender_ident);
1319 if (received_protocol)
1320 g = string_append(g, 2, US" P=", received_protocol);
1321 if (LOGGING(pipelining) && f.smtp_in_pipelining_advertised)
1322 {
1323 g = string_catn(g, US" L", 2);
1324 #ifdef EXPERIMENTAL_PIPE_CONNECT
1325 if (f.smtp_in_early_pipe_used)
1326 g = string_catn(g, US"*", 1);
1327 else if (f.smtp_in_early_pipe_advertised)
1328 g = string_catn(g, US".", 1);
1329 #endif
1330 if (!f.smtp_in_pipelining_used)
1331 g = string_catn(g, US"-", 1);
1332 }
1333 return g;
1334 }
1335
1336
1337
1338 #ifdef WITH_CONTENT_SCAN
1339
1340 /*************************************************
1341 * Run the MIME ACL on a message *
1342 *************************************************/
1343
1344 /* This code is in a subroutine so that it can be used for both SMTP
1345 and non-SMTP messages. It is called with a non-NULL ACL pointer.
1346
1347 Arguments:
1348 acl The ACL to run (acl_smtp_mime or acl_not_smtp_mime)
1349 smtp_yield_ptr Set FALSE to kill messages after dropped connection
1350 smtp_reply_ptr Where SMTP reply is being built
1351 blackholed_by_ptr Where "blackholed by" message is being built
1352
1353 Returns: TRUE to carry on; FALSE to abandon the message
1354 */
1355
1356 static BOOL
1357 run_mime_acl(uschar *acl, BOOL *smtp_yield_ptr, uschar **smtp_reply_ptr,
1358 uschar **blackholed_by_ptr)
1359 {
1360 FILE *mbox_file;
1361 uschar * rfc822_file_path = NULL;
1362 unsigned long mbox_size;
1363 header_line *my_headerlist;
1364 uschar *user_msg, *log_msg;
1365 int mime_part_count_buffer = -1;
1366 uschar * mbox_filename;
1367 int rc = OK;
1368
1369 /* check if it is a MIME message */
1370
1371 for (my_headerlist = header_list; my_headerlist; my_headerlist = my_headerlist->next)
1372 if ( my_headerlist->type != '*' /* skip deleted headers */
1373 && strncmpic(my_headerlist->text, US"Content-Type:", 13) == 0
1374 )
1375 {
1376 DEBUG(D_receive) debug_printf("Found Content-Type: header - executing acl_smtp_mime.\n");
1377 goto DO_MIME_ACL;
1378 }
1379
1380 DEBUG(D_receive) debug_printf("No Content-Type: header - presumably not a MIME message.\n");
1381 return TRUE;
1382
1383 DO_MIME_ACL:
1384
1385 /* make sure the eml mbox file is spooled up */
1386 if (!(mbox_file = spool_mbox(&mbox_size, NULL, &mbox_filename)))
1387 { /* error while spooling */
1388 log_write(0, LOG_MAIN|LOG_PANIC,
1389 "acl_smtp_mime: error while creating mbox spool file, message temporarily rejected.");
1390 Uunlink(spool_name);
1391 unspool_mbox();
1392 #ifdef EXPERIMENTAL_DCC
1393 dcc_ok = 0;
1394 #endif
1395 smtp_respond(US"451", 3, TRUE, US"temporary local problem");
1396 message_id[0] = 0; /* Indicate no message accepted */
1397 *smtp_reply_ptr = US""; /* Indicate reply already sent */
1398 return FALSE; /* Indicate skip to end of receive function */
1399 }
1400
1401 mime_is_rfc822 = 0;
1402
1403 MIME_ACL_CHECK:
1404 mime_part_count = -1;
1405 rc = mime_acl_check(acl, mbox_file, NULL, &user_msg, &log_msg);
1406 (void)fclose(mbox_file);
1407
1408 if (rfc822_file_path)
1409 {
1410 mime_part_count = mime_part_count_buffer;
1411
1412 if (unlink(CS rfc822_file_path) == -1)
1413 {
1414 log_write(0, LOG_PANIC,
1415 "acl_smtp_mime: can't unlink RFC822 spool file, skipping.");
1416 goto END_MIME_ACL;
1417 }
1418 rfc822_file_path = NULL;
1419 }
1420
1421 /* check if we must check any message/rfc822 attachments */
1422 if (rc == OK)
1423 {
1424 uschar * scandir = string_copyn(mbox_filename,
1425 Ustrrchr(mbox_filename, '/') - mbox_filename);
1426 struct dirent * entry;
1427 DIR * tempdir;
1428
1429 for (tempdir = opendir(CS scandir); entry = readdir(tempdir); )
1430 if (strncmpic(US entry->d_name, US"__rfc822_", 9) == 0)
1431 {
1432 rfc822_file_path = string_sprintf("%s/%s", scandir, entry->d_name);
1433 DEBUG(D_receive)
1434 debug_printf("RFC822 attachment detected: running MIME ACL for '%s'\n",
1435 rfc822_file_path);
1436 break;
1437 }
1438 closedir(tempdir);
1439
1440 if (rfc822_file_path)
1441 {
1442 if ((mbox_file = Ufopen(rfc822_file_path, "rb")))
1443 {
1444 /* set RFC822 expansion variable */
1445 mime_is_rfc822 = 1;
1446 mime_part_count_buffer = mime_part_count;
1447 goto MIME_ACL_CHECK;
1448 }
1449 log_write(0, LOG_PANIC,
1450 "acl_smtp_mime: can't open RFC822 spool file, skipping.");
1451 unlink(CS rfc822_file_path);
1452 }
1453 }
1454
1455 END_MIME_ACL:
1456 add_acl_headers(ACL_WHERE_MIME, US"MIME");
1457 if (rc == DISCARD)
1458 {
1459 recipients_count = 0;
1460 *blackholed_by_ptr = US"MIME ACL";
1461 cancel_cutthrough_connection(TRUE, US"mime acl discard");
1462 }
1463 else if (rc != OK)
1464 {
1465 Uunlink(spool_name);
1466 cancel_cutthrough_connection(TRUE, US"mime acl not ok");
1467 unspool_mbox();
1468 #ifdef EXPERIMENTAL_DCC
1469 dcc_ok = 0;
1470 #endif
1471 if (smtp_input)
1472 {
1473 if (smtp_handle_acl_fail(ACL_WHERE_MIME, rc, user_msg, log_msg) != 0)
1474 *smtp_yield_ptr = FALSE; /* No more messages after dropped connection */
1475 *smtp_reply_ptr = US""; /* Indicate reply already sent */
1476 }
1477 message_id[0] = 0; /* Indicate no message accepted */
1478 return FALSE; /* Cause skip to end of receive function */
1479 }
1480
1481 return TRUE;
1482 }
1483
1484 #endif /* WITH_CONTENT_SCAN */
1485
1486
1487
1488 void
1489 received_header_gen(void)
1490 {
1491 uschar *received;
1492 uschar *timestamp;
1493 header_line *received_header= header_list;
1494
1495 timestamp = expand_string(US"${tod_full}");
1496 if (recipients_count == 1) received_for = recipients_list[0].address;
1497 received = expand_string(received_header_text);
1498 received_for = NULL;
1499
1500 if (!received)
1501 {
1502 if(spool_name[0] != 0)
1503 Uunlink(spool_name); /* Lose the data file */
1504 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" "
1505 "(received_header_text) failed: %s", string_printing(received_header_text),
1506 expand_string_message);
1507 }
1508
1509 /* The first element on the header chain is reserved for the Received header,
1510 so all we have to do is fill in the text pointer, and set the type. However, if
1511 the result of the expansion is an empty string, we leave the header marked as
1512 "old" so as to refrain from adding a Received header. */
1513
1514 if (received[0] == 0)
1515 {
1516 received_header->text = string_sprintf("Received: ; %s\n", timestamp);
1517 received_header->type = htype_old;
1518 }
1519 else
1520 {
1521 received_header->text = string_sprintf("%s; %s\n", received, timestamp);
1522 received_header->type = htype_received;
1523 }
1524
1525 received_header->slen = Ustrlen(received_header->text);
1526
1527 DEBUG(D_receive) debug_printf(">>Generated Received: header line\n%c %s",
1528 received_header->type, received_header->text);
1529 }
1530
1531
1532
1533 /*************************************************
1534 * Receive message *
1535 *************************************************/
1536
1537 /* Receive a message on the given input, and put it into a pair of spool files.
1538 Either a non-null list of recipients, or the extract flag will be true, or
1539 both. The flag sender_local is true for locally generated messages. The flag
1540 submission_mode is true if an ACL has obeyed "control = submission". The flag
1541 suppress_local_fixups is true if an ACL has obeyed "control =
1542 suppress_local_fixups" or -G was passed on the command-line.
1543 The flag smtp_input is true if the message is to be
1544 handled using SMTP conventions about termination and lines starting with dots.
1545 For non-SMTP messages, dot_ends is true for dot-terminated messages.
1546
1547 If a message was successfully read, message_id[0] will be non-zero.
1548
1549 The general actions of this function are:
1550
1551 . Read the headers of the message (if any) into a chain of store
1552 blocks.
1553
1554 . If there is a "sender:" header and the message is locally originated,
1555 throw it away, unless the caller is trusted, or unless
1556 active_local_sender_retain is set - which can only happen if
1557 active_local_from_check is false.
1558
1559 . If recipients are to be extracted from the message, build the
1560 recipients list from the headers, removing any that were on the
1561 original recipients list (unless extract_addresses_remove_arguments is
1562 false), and at the same time, remove any bcc header that may be present.
1563
1564 . Get the spool file for the data, sort out its unique name, open
1565 and lock it (but don't give it the name yet).
1566
1567 . Generate a "Message-Id" header if the message doesn't have one, for
1568 locally-originated messages.
1569
1570 . Generate a "Received" header.
1571
1572 . Ensure the recipients list is fully qualified and rewritten if necessary.
1573
1574 . If there are any rewriting rules, apply them to the sender address
1575 and also to the headers.
1576
1577 . If there is no from: header, generate one, for locally-generated messages
1578 and messages in "submission mode" only.
1579
1580 . If the sender is local, check that from: is correct, and if not, generate
1581 a Sender: header, unless message comes from a trusted caller, or this
1582 feature is disabled by active_local_from_check being false.
1583
1584 . If there is no "date" header, generate one, for locally-originated
1585 or submission mode messages only.
1586
1587 . Copy the rest of the input, or up to a terminating "." if in SMTP or
1588 dot_ends mode, to the data file. Leave it open, to hold the lock.
1589
1590 . Write the envelope and the headers to a new file.
1591
1592 . Set the name for the header file; close it.
1593
1594 . Set the name for the data file; close it.
1595
1596 Because this function can potentially be called many times in a single
1597 SMTP connection, all store should be got by store_get(), so that it will be
1598 automatically retrieved after the message is accepted.
1599
1600 FUDGE: It seems that sites on the net send out messages with just LF
1601 terminators, despite the warnings in the RFCs, and other MTAs handle this. So
1602 we make the CRs optional in all cases.
1603
1604 July 2003: Bare CRs in messages, especially in header lines, cause trouble. A
1605 new regime is now in place in which bare CRs in header lines are turned into LF
1606 followed by a space, so as not to terminate the header line.
1607
1608 February 2004: A bare LF in a header line in a message whose first line was
1609 terminated by CRLF is treated in the same way as a bare CR.
1610
1611 Arguments:
1612 extract_recip TRUE if recipients are to be extracted from the message's
1613 headers
1614
1615 Returns: TRUE there are more messages to be read (SMTP input)
1616 FALSE there are no more messages to be read (non-SMTP input
1617 or SMTP connection collapsed, or other failure)
1618
1619 When reading a message for filter testing, the returned value indicates
1620 whether the headers (which is all that is read) were terminated by '.' or
1621 not. */
1622
1623 BOOL
1624 receive_msg(BOOL extract_recip)
1625 {
1626 int i;
1627 int rc = FAIL;
1628 int msg_size = 0;
1629 int process_info_len = Ustrlen(process_info);
1630 int error_rc = error_handling == ERRORS_SENDER
1631 ? errors_sender_rc : EXIT_FAILURE;
1632 int header_size = 256;
1633 int start, end, domain;
1634 int id_resolution = 0;
1635 int had_zero = 0;
1636 int prevlines_length = 0;
1637
1638 int ptr = 0;
1639
1640 BOOL contains_resent_headers = FALSE;
1641 BOOL extracted_ignored = FALSE;
1642 BOOL first_line_ended_crlf = TRUE_UNSET;
1643 BOOL smtp_yield = TRUE;
1644 BOOL yield = FALSE;
1645
1646 BOOL resents_exist = FALSE;
1647 uschar *resent_prefix = US"";
1648 uschar *blackholed_by = NULL;
1649 uschar *blackhole_log_msg = US"";
1650 enum {NOT_TRIED, TMP_REJ, PERM_REJ, ACCEPTED} cutthrough_done = NOT_TRIED;
1651
1652 flock_t lock_data;
1653 error_block *bad_addresses = NULL;
1654
1655 uschar *frozen_by = NULL;
1656 uschar *queued_by = NULL;
1657
1658 uschar *errmsg;
1659 gstring * g;
1660 struct stat statbuf;
1661
1662 /* Final message to give to SMTP caller, and messages from ACLs */
1663
1664 uschar *smtp_reply = NULL;
1665 uschar *user_msg, *log_msg;
1666
1667 /* Working header pointers */
1668
1669 header_line *h, *next;
1670
1671 /* Flags for noting the existence of certain headers (only one left) */
1672
1673 BOOL date_header_exists = FALSE;
1674
1675 /* Pointers to receive the addresses of headers whose contents we need. */
1676
1677 header_line *from_header = NULL;
1678 header_line *subject_header = NULL;
1679 header_line *msgid_header = NULL;
1680 header_line *received_header;
1681
1682 #ifdef EXPERIMENTAL_DMARC
1683 int dmarc_up = 0;
1684 #endif /* EXPERIMENTAL_DMARC */
1685
1686 /* Variables for use when building the Received: header. */
1687
1688 uschar *timestamp;
1689 int tslen;
1690
1691
1692 /* Release any open files that might have been cached while preparing to
1693 accept the message - e.g. by verifying addresses - because reading a message
1694 might take a fair bit of real time. */
1695
1696 search_tidyup();
1697
1698 /* Extracting the recipient list from an input file is incompatible with
1699 cutthrough delivery with the no-spool option. It shouldn't be possible
1700 to set up the combination, but just in case kill any ongoing connection. */
1701 if (extract_recip || !smtp_input)
1702 cancel_cutthrough_connection(TRUE, US"not smtp input");
1703
1704 /* Initialize the chain of headers by setting up a place-holder for Received:
1705 header. Temporarily mark it as "old", i.e. not to be used. We keep header_last
1706 pointing to the end of the chain to make adding headers simple. */
1707
1708 received_header = header_list = header_last = store_get(sizeof(header_line));
1709 header_list->next = NULL;
1710 header_list->type = htype_old;
1711 header_list->text = NULL;
1712 header_list->slen = 0;
1713
1714 /* Control block for the next header to be read. */
1715
1716 next = store_get(sizeof(header_line));
1717 next->text = store_get(header_size);
1718
1719 /* Initialize message id to be null (indicating no message read), and the
1720 header names list to be the normal list. Indicate there is no data file open
1721 yet, initialize the size and warning count, and deal with no size limit. */
1722
1723 message_id[0] = 0;
1724 spool_data_file = NULL;
1725 data_fd = -1;
1726 spool_name = US"";
1727 message_size = 0;
1728 warning_count = 0;
1729 received_count = 1; /* For the one we will add */
1730
1731 if (thismessage_size_limit <= 0) thismessage_size_limit = INT_MAX;
1732
1733 /* While reading the message, the following counts are computed. */
1734
1735 message_linecount = body_linecount = body_zerocount =
1736 max_received_linelength = 0;
1737
1738 #ifndef DISABLE_DKIM
1739 /* Call into DKIM to set up the context. In CHUNKING mode
1740 we clear the dot-stuffing flag */
1741 if (smtp_input && !smtp_batched_input && !f.dkim_disable_verify)
1742 dkim_exim_verify_init(chunking_state <= CHUNKING_OFFERED);
1743 #endif
1744
1745 #ifdef EXPERIMENTAL_DMARC
1746 /* initialize libopendmarc */
1747 dmarc_up = dmarc_init();
1748 #endif
1749
1750 /* Remember the time of reception. Exim uses time+pid for uniqueness of message
1751 ids, and fractions of a second are required. See the comments that precede the
1752 message id creation below. */
1753
1754 (void)gettimeofday(&message_id_tv, NULL);
1755
1756 /* For other uses of the received time we can operate with granularity of one
1757 second, and for that we use the global variable received_time. This is for
1758 things like ultimate message timeouts. */
1759
1760 received_time = message_id_tv;
1761
1762 /* If SMTP input, set the special handler for timeouts. The alarm() calls
1763 happen in the smtp_getc() function when it refills its buffer. */
1764
1765 had_data_timeout = 0;
1766 if (smtp_input)
1767 os_non_restarting_signal(SIGALRM, data_timeout_handler);
1768
1769 /* If not SMTP input, timeout happens only if configured, and we just set a
1770 single timeout for the whole message. */
1771
1772 else if (receive_timeout > 0)
1773 {
1774 os_non_restarting_signal(SIGALRM, data_timeout_handler);
1775 ALARM(receive_timeout);
1776 }
1777
1778 /* SIGTERM and SIGINT are caught always. */
1779
1780 had_data_sigint = 0;
1781 signal(SIGTERM, data_sigterm_sigint_handler);
1782 signal(SIGINT, data_sigterm_sigint_handler);
1783
1784 /* Header lines in messages are not supposed to be very long, though when
1785 unfolded, to: and cc: headers can take up a lot of store. We must also cope
1786 with the possibility of junk being thrown at us. Start by getting 256 bytes for
1787 storing the header, and extend this as necessary using string_cat().
1788
1789 To cope with total lunacies, impose an upper limit on the length of the header
1790 section of the message, as otherwise the store will fill up. We must also cope
1791 with the possibility of binary zeros in the data. Hence we cannot use fgets().
1792 Folded header lines are joined into one string, leaving the '\n' characters
1793 inside them, so that writing them out reproduces the input.
1794
1795 Loop for each character of each header; the next structure for chaining the
1796 header is set up already, with ptr the offset of the next character in
1797 next->text. */
1798
1799 for (;;)
1800 {
1801 int ch = (receive_getc)(GETC_BUFFER_UNLIMITED);
1802
1803 /* If we hit EOF on a SMTP connection, it's an error, since incoming
1804 SMTP must have a correct "." terminator. */
1805
1806 if (ch == EOF && smtp_input /* && !smtp_batched_input */)
1807 {
1808 smtp_reply = handle_lost_connection(US" (header)");
1809 smtp_yield = FALSE;
1810 goto TIDYUP; /* Skip to end of function */
1811 }
1812
1813 /* See if we are at the current header's size limit - there must be at least
1814 four bytes left. This allows for the new character plus a zero, plus two for
1815 extra insertions when we are playing games with dots and carriage returns. If
1816 we are at the limit, extend the text buffer. This could have been done
1817 automatically using string_cat() but because this is a tightish loop storing
1818 only one character at a time, we choose to do it inline. Normally
1819 store_extend() will be able to extend the block; only at the end of a big
1820 store block will a copy be needed. To handle the case of very long headers
1821 (and sometimes lunatic messages can have ones that are 100s of K long) we
1822 call store_release() for strings that have been copied - if the string is at
1823 the start of a block (and therefore the only thing in it, because we aren't
1824 doing any other gets), the block gets freed. We can only do this release if
1825 there were no allocations since the once that we want to free. */
1826
1827 if (ptr >= header_size - 4)
1828 {
1829 int oldsize = header_size;
1830 /* header_size += 256; */
1831 header_size *= 2;
1832 if (!store_extend(next->text, oldsize, header_size))
1833 next->text = store_newblock(next->text, header_size, ptr);
1834 }
1835
1836 /* Cope with receiving a binary zero. There is dispute about whether
1837 these should be allowed in RFC 822 messages. The middle view is that they
1838 should not be allowed in headers, at least. Exim takes this attitude at
1839 the moment. We can't just stomp on them here, because we don't know that
1840 this line is a header yet. Set a flag to cause scanning later. */
1841
1842 if (ch == 0) had_zero++;
1843
1844 /* Test for termination. Lines in remote SMTP are terminated by CRLF, while
1845 those from data files use just LF. Treat LF in local SMTP input as a
1846 terminator too. Treat EOF as a line terminator always. */
1847
1848 if (ch == EOF) goto EOL;
1849
1850 /* FUDGE: There are sites out there that don't send CRs before their LFs, and
1851 other MTAs accept this. We are therefore forced into this "liberalisation"
1852 too, so we accept LF as a line terminator whatever the source of the message.
1853 However, if the first line of the message ended with a CRLF, we treat a bare
1854 LF specially by inserting a white space after it to ensure that the header
1855 line is not terminated. */
1856
1857 if (ch == '\n')
1858 {
1859 if (first_line_ended_crlf == TRUE_UNSET) first_line_ended_crlf = FALSE;
1860 else if (first_line_ended_crlf) receive_ungetc(' ');
1861 goto EOL;
1862 }
1863
1864 /* This is not the end of the line. If this is SMTP input and this is
1865 the first character in the line and it is a "." character, ignore it.
1866 This implements the dot-doubling rule, though header lines starting with
1867 dots aren't exactly common. They are legal in RFC 822, though. If the
1868 following is CRLF or LF, this is the line that that terminates the
1869 entire message. We set message_ended to indicate this has happened (to
1870 prevent further reading), and break out of the loop, having freed the
1871 empty header, and set next = NULL to indicate no data line. */
1872
1873 if (ptr == 0 && ch == '.' && f.dot_ends)
1874 {
1875 ch = (receive_getc)(GETC_BUFFER_UNLIMITED);
1876 if (ch == '\r')
1877 {
1878 ch = (receive_getc)(GETC_BUFFER_UNLIMITED);
1879 if (ch != '\n')
1880 {
1881 receive_ungetc(ch);
1882 ch = '\r'; /* Revert to CR */
1883 }
1884 }
1885 if (ch == '\n')
1886 {
1887 message_ended = END_DOT;
1888 store_reset(next);
1889 next = NULL;
1890 break; /* End character-reading loop */
1891 }
1892
1893 /* For non-SMTP input, the dot at the start of the line was really a data
1894 character. What is now in ch is the following character. We guaranteed
1895 enough space for this above. */
1896
1897 if (!smtp_input)
1898 {
1899 next->text[ptr++] = '.';
1900 message_size++;
1901 }
1902 }
1903
1904 /* If CR is immediately followed by LF, end the line, ignoring the CR, and
1905 remember this case if this is the first line ending. */
1906
1907 if (ch == '\r')
1908 {
1909 ch = (receive_getc)(GETC_BUFFER_UNLIMITED);
1910 if (ch == '\n')
1911 {
1912 if (first_line_ended_crlf == TRUE_UNSET) first_line_ended_crlf = TRUE;
1913 goto EOL;
1914 }
1915
1916 /* Otherwise, put back the character after CR, and turn the bare CR
1917 into LF SP. */
1918
1919 ch = (receive_ungetc)(ch);
1920 next->text[ptr++] = '\n';
1921 message_size++;
1922 ch = ' ';
1923 }
1924
1925 /* We have a data character for the header line. */
1926
1927 next->text[ptr++] = ch; /* Add to buffer */
1928 message_size++; /* Total message size so far */
1929
1930 /* Handle failure due to a humungously long header section. The >= allows
1931 for the terminating \n. Add what we have so far onto the headers list so
1932 that it gets reflected in any error message, and back up the just-read
1933 character. */
1934
1935 if (message_size >= header_maxsize)
1936 {
1937 next->text[ptr] = 0;
1938 next->slen = ptr;
1939 next->type = htype_other;
1940 next->next = NULL;
1941 header_last->next = next;
1942 header_last = next;
1943
1944 log_write(0, LOG_MAIN, "ridiculously long message header received from "
1945 "%s (more than %d characters): message abandoned",
1946 f.sender_host_unknown ? sender_ident : sender_fullhost, header_maxsize);
1947
1948 if (smtp_input)
1949 {
1950 smtp_reply = US"552 Message header is ridiculously long";
1951 receive_swallow_smtp();
1952 goto TIDYUP; /* Skip to end of function */
1953 }
1954
1955 else
1956 {
1957 give_local_error(ERRMESS_VLONGHEADER,
1958 string_sprintf("message header longer than %d characters received: "
1959 "message not accepted", header_maxsize), US"", error_rc, stdin,
1960 header_list->next);
1961 /* Does not return */
1962 }
1963 }
1964
1965 continue; /* With next input character */
1966
1967 /* End of header line reached */
1968
1969 EOL:
1970
1971 /* Keep track of lines for BSMTP errors and overall message_linecount. */
1972
1973 receive_linecount++;
1974 message_linecount++;
1975
1976 /* Keep track of maximum line length */
1977
1978 if (ptr - prevlines_length > max_received_linelength)
1979 max_received_linelength = ptr - prevlines_length;
1980 prevlines_length = ptr + 1;
1981
1982 /* Now put in the terminating newline. There is always space for
1983 at least two more characters. */
1984
1985 next->text[ptr++] = '\n';
1986 message_size++;
1987
1988 /* A blank line signals the end of the headers; release the unwanted
1989 space and set next to NULL to indicate this. */
1990
1991 if (ptr == 1)
1992 {
1993 store_reset(next);
1994 next = NULL;
1995 break;
1996 }
1997
1998 /* There is data in the line; see if the next input character is a
1999 whitespace character. If it is, we have a continuation of this header line.
2000 There is always space for at least one character at this point. */
2001
2002 if (ch != EOF)
2003 {
2004 int nextch = (receive_getc)(GETC_BUFFER_UNLIMITED);
2005 if (nextch == ' ' || nextch == '\t')
2006 {
2007 next->text[ptr++] = nextch;
2008 message_size++;
2009 continue; /* Iterate the loop */
2010 }
2011 else if (nextch != EOF) (receive_ungetc)(nextch); /* For next time */
2012 else ch = EOF; /* Cause main loop to exit at end */
2013 }
2014
2015 /* We have got to the real line end. Terminate the string and release store
2016 beyond it. If it turns out to be a real header, internal binary zeros will
2017 be squashed later. */
2018
2019 next->text[ptr] = 0;
2020 next->slen = ptr;
2021 store_reset(next->text + ptr + 1);
2022
2023 /* Check the running total size against the overall message size limit. We
2024 don't expect to fail here, but if the overall limit is set less than MESSAGE_
2025 MAXSIZE and a big header is sent, we want to catch it. Just stop reading
2026 headers - the code to read the body will then also hit the buffer. */
2027
2028 if (message_size > thismessage_size_limit) break;
2029
2030 /* A line that is not syntactically correct for a header also marks
2031 the end of the headers. In this case, we leave next containing the
2032 first data line. This might actually be several lines because of the
2033 continuation logic applied above, but that doesn't matter.
2034
2035 It turns out that smail, and presumably sendmail, accept leading lines
2036 of the form
2037
2038 From ph10 Fri Jan 5 12:35 GMT 1996
2039
2040 in messages. The "mail" command on Solaris 2 sends such lines. I cannot
2041 find any documentation of this, but for compatibility it had better be
2042 accepted. Exim restricts it to the case of non-smtp messages, and
2043 treats it as an alternative to the -f command line option. Thus it is
2044 ignored except for trusted users or filter testing. Otherwise it is taken
2045 as the sender address, unless -f was used (sendmail compatibility).
2046
2047 It further turns out that some UUCPs generate the From_line in a different
2048 format, e.g.
2049
2050 From ph10 Fri, 7 Jan 97 14:00:00 GMT
2051
2052 The regex for matching these things is now capable of recognizing both
2053 formats (including 2- and 4-digit years in the latter). In fact, the regex
2054 is now configurable, as is the expansion string to fish out the sender.
2055
2056 Even further on it has been discovered that some broken clients send
2057 these lines in SMTP messages. There is now an option to ignore them from
2058 specified hosts or networks. Sigh. */
2059
2060 if ( header_last == header_list
2061 && ( !smtp_input
2062 || ( sender_host_address
2063 && verify_check_host(&ignore_fromline_hosts) == OK
2064 )
2065 || (!sender_host_address && ignore_fromline_local)
2066 )
2067 && regex_match_and_setup(regex_From, next->text, 0, -1)
2068 )
2069 {
2070 if (!f.sender_address_forced)
2071 {
2072 uschar *uucp_sender = expand_string(uucp_from_sender);
2073 if (!uucp_sender)
2074 log_write(0, LOG_MAIN|LOG_PANIC,
2075 "expansion of \"%s\" failed after matching "
2076 "\"From \" line: %s", uucp_from_sender, expand_string_message);
2077 else
2078 {
2079 int start, end, domain;
2080 uschar *errmess;
2081 uschar *newsender = parse_extract_address(uucp_sender, &errmess,
2082 &start, &end, &domain, TRUE);
2083 if (newsender)
2084 {
2085 if (domain == 0 && newsender[0] != 0)
2086 newsender = rewrite_address_qualify(newsender, FALSE);
2087
2088 if (filter_test != FTEST_NONE || receive_check_set_sender(newsender))
2089 {
2090 sender_address = newsender;
2091
2092 if (f.trusted_caller || filter_test != FTEST_NONE)
2093 {
2094 authenticated_sender = NULL;
2095 originator_name = US"";
2096 f.sender_local = FALSE;
2097 }
2098
2099 if (filter_test != FTEST_NONE)
2100 printf("Sender taken from \"From \" line\n");
2101 }
2102 }
2103 }
2104 }
2105 }
2106
2107 /* Not a leading "From " line. Check to see if it is a valid header line.
2108 Header names may contain any non-control characters except space and colon,
2109 amazingly. */
2110
2111 else
2112 {
2113 uschar *p = next->text;
2114
2115 /* If not a valid header line, break from the header reading loop, leaving
2116 next != NULL, indicating that it holds the first line of the body. */
2117
2118 if (isspace(*p)) break;
2119 while (mac_isgraph(*p) && *p != ':') p++;
2120 while (isspace(*p)) p++;
2121 if (*p != ':')
2122 {
2123 body_zerocount = had_zero;
2124 break;
2125 }
2126
2127 /* We have a valid header line. If there were any binary zeroes in
2128 the line, stomp on them here. */
2129
2130 if (had_zero > 0)
2131 for (p = next->text; p < next->text + ptr; p++) if (*p == 0) *p = '?';
2132
2133 /* It is perfectly legal to have an empty continuation line
2134 at the end of a header, but it is confusing to humans
2135 looking at such messages, since it looks like a blank line.
2136 Reduce confusion by removing redundant white space at the
2137 end. We know that there is at least one printing character
2138 (the ':' tested for above) so there is no danger of running
2139 off the end. */
2140
2141 p = next->text + ptr - 2;
2142 for (;;)
2143 {
2144 while (*p == ' ' || *p == '\t') p--;
2145 if (*p != '\n') break;
2146 ptr = (p--) - next->text + 1;
2147 message_size -= next->slen - ptr;
2148 next->text[ptr] = 0;
2149 next->slen = ptr;
2150 }
2151
2152 /* Add the header to the chain */
2153
2154 next->type = htype_other;
2155 next->next = NULL;
2156 header_last->next = next;
2157 header_last = next;
2158
2159 /* Check the limit for individual line lengths. This comes after adding to
2160 the chain so that the failing line is reflected if a bounce is generated
2161 (for a local message). */
2162
2163 if (header_line_maxsize > 0 && next->slen > header_line_maxsize)
2164 {
2165 log_write(0, LOG_MAIN, "overlong message header line received from "
2166 "%s (more than %d characters): message abandoned",
2167 f.sender_host_unknown ? sender_ident : sender_fullhost,
2168 header_line_maxsize);
2169
2170 if (smtp_input)
2171 {
2172 smtp_reply = US"552 A message header line is too long";
2173 receive_swallow_smtp();
2174 goto TIDYUP; /* Skip to end of function */
2175 }
2176
2177 else
2178 give_local_error(ERRMESS_VLONGHDRLINE,
2179 string_sprintf("message header line longer than %d characters "
2180 "received: message not accepted", header_line_maxsize), US"",
2181 error_rc, stdin, header_list->next);
2182 /* Does not return */
2183 }
2184
2185 /* Note if any resent- fields exist. */
2186
2187 if (!resents_exist && strncmpic(next->text, US"resent-", 7) == 0)
2188 {
2189 resents_exist = TRUE;
2190 resent_prefix = US"Resent-";
2191 }
2192 }
2193
2194 /* Reject CHUNKING messages that do not CRLF their first header line */
2195
2196 if (!first_line_ended_crlf && chunking_state > CHUNKING_OFFERED)
2197 {
2198 log_write(L_size_reject, LOG_MAIN|LOG_REJECT, "rejected from <%s>%s%s%s%s: "
2199 "Non-CRLF-terminated header, under CHUNKING: message abandoned",
2200 sender_address,
2201 sender_fullhost ? " H=" : "", sender_fullhost ? sender_fullhost : US"",
2202 sender_ident ? " U=" : "", sender_ident ? sender_ident : US"");
2203 smtp_printf("552 Message header not CRLF terminated\r\n", FALSE);
2204 bdat_flush_data();
2205 smtp_reply = US"";
2206 goto TIDYUP; /* Skip to end of function */
2207 }
2208
2209 /* The line has been handled. If we have hit EOF, break out of the loop,
2210 indicating no pending data line. */
2211
2212 if (ch == EOF) { next = NULL; break; }
2213
2214 /* Set up for the next header */
2215
2216 header_size = 256;
2217 next = store_get(sizeof(header_line));
2218 next->text = store_get(header_size);
2219 ptr = 0;
2220 had_zero = 0;
2221 prevlines_length = 0;
2222 } /* Continue, starting to read the next header */
2223
2224 /* At this point, we have read all the headers into a data structure in main
2225 store. The first header is still the dummy placeholder for the Received: header
2226 we are going to generate a bit later on. If next != NULL, it contains the first
2227 data line - which terminated the headers before reaching a blank line (not the
2228 normal case). */
2229
2230 DEBUG(D_receive)
2231 {
2232 debug_printf(">>Headers received:\n");
2233 for (h = header_list->next; h; h = h->next)
2234 debug_printf("%s", h->text);
2235 debug_printf("\n");
2236 }
2237
2238 /* End of file on any SMTP connection is an error. If an incoming SMTP call
2239 is dropped immediately after valid headers, the next thing we will see is EOF.
2240 We must test for this specially, as further down the reading of the data is
2241 skipped if already at EOF. */
2242
2243 if (smtp_input && (receive_feof)())
2244 {
2245 smtp_reply = handle_lost_connection(US" (after header)");
2246 smtp_yield = FALSE;
2247 goto TIDYUP; /* Skip to end of function */
2248 }
2249
2250 /* If this is a filter test run and no headers were read, output a warning
2251 in case there is a mistake in the test message. */
2252
2253 if (filter_test != FTEST_NONE && header_list->next == NULL)
2254 printf("Warning: no message headers read\n");
2255
2256
2257 /* Scan the headers to identify them. Some are merely marked for later
2258 processing; some are dealt with here. */
2259
2260 for (h = header_list->next; h; h = h->next)
2261 {
2262 BOOL is_resent = strncmpic(h->text, US"resent-", 7) == 0;
2263 if (is_resent) contains_resent_headers = TRUE;
2264
2265 switch (header_checkname(h, is_resent))
2266 {
2267 case htype_bcc:
2268 h->type = htype_bcc; /* Both Bcc: and Resent-Bcc: */
2269 break;
2270
2271 case htype_cc:
2272 h->type = htype_cc; /* Both Cc: and Resent-Cc: */
2273 break;
2274
2275 /* Record whether a Date: or Resent-Date: header exists, as appropriate. */
2276
2277 case htype_date:
2278 if (!resents_exist || is_resent) date_header_exists = TRUE;
2279 break;
2280
2281 /* Same comments as about Return-Path: below. */
2282
2283 case htype_delivery_date:
2284 if (delivery_date_remove) h->type = htype_old;
2285 break;
2286
2287 /* Same comments as about Return-Path: below. */
2288
2289 case htype_envelope_to:
2290 if (envelope_to_remove) h->type = htype_old;
2291 break;
2292
2293 /* Mark all "From:" headers so they get rewritten. Save the one that is to
2294 be used for Sender: checking. For Sendmail compatibility, if the "From:"
2295 header consists of just the login id of the user who called Exim, rewrite
2296 it with the gecos field first. Apply this rule to Resent-From: if there
2297 are resent- fields. */
2298
2299 case htype_from:
2300 h->type = htype_from;
2301 if (!resents_exist || is_resent)
2302 {
2303 from_header = h;
2304 if (!smtp_input)
2305 {
2306 int len;
2307 uschar *s = Ustrchr(h->text, ':') + 1;
2308 while (isspace(*s)) s++;
2309 len = h->slen - (s - h->text) - 1;
2310 if (Ustrlen(originator_login) == len &&
2311 strncmpic(s, originator_login, len) == 0)
2312 {
2313 uschar *name = is_resent? US"Resent-From" : US"From";
2314 header_add(htype_from, "%s: %s <%s@%s>\n", name, originator_name,
2315 originator_login, qualify_domain_sender);
2316 from_header = header_last;
2317 h->type = htype_old;
2318 DEBUG(D_receive|D_rewrite)
2319 debug_printf("rewrote \"%s:\" header using gecos\n", name);
2320 }
2321 }
2322 }
2323 break;
2324
2325 /* Identify the Message-id: header for generating "in-reply-to" in the
2326 autoreply transport. For incoming logging, save any resent- value. In both
2327 cases, take just the first of any multiples. */
2328
2329 case htype_id:
2330 if (!msgid_header && (!resents_exist || is_resent))
2331 {
2332 msgid_header = h;
2333 h->type = htype_id;
2334 }
2335 break;
2336
2337 /* Flag all Received: headers */
2338
2339 case htype_received:
2340 h->type = htype_received;
2341 received_count++;
2342 break;
2343
2344 /* "Reply-to:" is just noted (there is no resent-reply-to field) */
2345
2346 case htype_reply_to:
2347 h->type = htype_reply_to;
2348 break;
2349
2350 /* The Return-path: header is supposed to be added to messages when
2351 they leave the SMTP system. We shouldn't receive messages that already
2352 contain Return-path. However, since Exim generates Return-path: on
2353 local delivery, resent messages may well contain it. We therefore
2354 provide an option (which defaults on) to remove any Return-path: headers
2355 on input. Removal actually means flagging as "old", which prevents the
2356 header being transmitted with the message. */
2357
2358 case htype_return_path:
2359 if (return_path_remove) h->type = htype_old;
2360
2361 /* If we are testing a mail filter file, use the value of the
2362 Return-Path: header to set up the return_path variable, which is not
2363 otherwise set. However, remove any <> that surround the address
2364 because the variable doesn't have these. */
2365
2366 if (filter_test != FTEST_NONE)
2367 {
2368 uschar *start = h->text + 12;
2369 uschar *end = start + Ustrlen(start);
2370 while (isspace(*start)) start++;
2371 while (end > start && isspace(end[-1])) end--;
2372 if (*start == '<' && end[-1] == '>')
2373 {
2374 start++;
2375 end--;
2376 }
2377 return_path = string_copyn(start, end - start);
2378 printf("Return-path taken from \"Return-path:\" header line\n");
2379 }
2380 break;
2381
2382 /* If there is a "Sender:" header and the message is locally originated,
2383 and from an untrusted caller and suppress_local_fixups is not set, or if we
2384 are in submission mode for a remote message, mark it "old" so that it will
2385 not be transmitted with the message, unless active_local_sender_retain is
2386 set. (This can only be true if active_local_from_check is false.) If there
2387 are any resent- headers in the message, apply this rule to Resent-Sender:
2388 instead of Sender:. Messages with multiple resent- header sets cannot be
2389 tidily handled. (For this reason, at least one MUA - Pine - turns old
2390 resent- headers into X-resent- headers when resending, leaving just one
2391 set.) */
2392
2393 case htype_sender:
2394 h->type = !f.active_local_sender_retain
2395 && ( f.sender_local && !f.trusted_caller && !f.suppress_local_fixups
2396 || f.submission_mode
2397 )
2398 && (!resents_exist || is_resent)
2399 ? htype_old : htype_sender;
2400 break;
2401
2402 /* Remember the Subject: header for logging. There is no Resent-Subject */
2403
2404 case htype_subject:
2405 subject_header = h;
2406 break;
2407
2408 /* "To:" gets flagged, and the existence of a recipient header is noted,
2409 whether it's resent- or not. */
2410
2411 case htype_to:
2412 h->type = htype_to;
2413 /****
2414 to_or_cc_header_exists = TRUE;
2415 ****/
2416 break;
2417 }
2418 }
2419
2420 /* Extract recipients from the headers if that is required (the -t option).
2421 Note that this is documented as being done *before* any address rewriting takes
2422 place. There are two possibilities:
2423
2424 (1) According to sendmail documentation for Solaris, IRIX, and HP-UX, any
2425 recipients already listed are to be REMOVED from the message. Smail 3 works
2426 like this. We need to build a non-recipients tree for that list, because in
2427 subsequent processing this data is held in a tree and that's what the
2428 spool_write_header() function expects. Make sure that non-recipient addresses
2429 are fully qualified and rewritten if necessary.
2430
2431 (2) According to other sendmail documentation, -t ADDS extracted recipients to
2432 those in the command line arguments (and it is rumoured some other MTAs do
2433 this). Therefore, there is an option to make Exim behave this way.
2434
2435 *** Notes on "Resent-" header lines ***
2436
2437 The presence of resent-headers in the message makes -t horribly ambiguous.
2438 Experiments with sendmail showed that it uses recipients for all resent-
2439 headers, totally ignoring the concept of "sets of resent- headers" as described
2440 in RFC 2822 section 3.6.6. Sendmail also amalgamates them into a single set
2441 with all the addresses in one instance of each header.
2442
2443 This seems to me not to be at all sensible. Before release 4.20, Exim 4 gave an
2444 error for -t if there were resent- headers in the message. However, after a
2445 discussion on the mailing list, I've learned that there are MUAs that use
2446 resent- headers with -t, and also that the stuff about sets of resent- headers
2447 and their ordering in RFC 2822 is generally ignored. An MUA that submits a
2448 message with -t and resent- header lines makes sure that only *its* resent-
2449 headers are present; previous ones are often renamed as X-resent- for example.
2450
2451 Consequently, Exim has been changed so that, if any resent- header lines are
2452 present, the recipients are taken from all of the appropriate resent- lines,
2453 and not from the ordinary To:, Cc:, etc. */
2454
2455 if (extract_recip)
2456 {
2457 int rcount = 0;
2458 error_block **bnext = &bad_addresses;
2459
2460 if (extract_addresses_remove_arguments)
2461 {
2462 while (recipients_count-- > 0)
2463 {
2464 uschar *s = rewrite_address(recipients_list[recipients_count].address,
2465 TRUE, TRUE, global_rewrite_rules, rewrite_existflags);
2466 tree_add_nonrecipient(s);
2467 }
2468 recipients_list = NULL;
2469 recipients_count = recipients_list_max = 0;
2470 }
2471
2472 /* Now scan the headers */
2473
2474 for (h = header_list->next; h; h = h->next)
2475 {
2476 if ((h->type == htype_to || h->type == htype_cc || h->type == htype_bcc) &&
2477 (!contains_resent_headers || strncmpic(h->text, US"resent-", 7) == 0))
2478 {
2479 uschar *s = Ustrchr(h->text, ':') + 1;
2480 while (isspace(*s)) s++;
2481
2482 f.parse_allow_group = TRUE; /* Allow address group syntax */
2483
2484 while (*s != 0)
2485 {
2486 uschar *ss = parse_find_address_end(s, FALSE);
2487 uschar *recipient, *errmess, *p, *pp;
2488 int start, end, domain;
2489
2490 /* Check on maximum */
2491
2492 if (recipients_max > 0 && ++rcount > recipients_max)
2493 give_local_error(ERRMESS_TOOMANYRECIP, US"too many recipients",
2494 US"message rejected: ", error_rc, stdin, NULL);
2495 /* Does not return */
2496
2497 /* Make a copy of the address, and remove any internal newlines. These
2498 may be present as a result of continuations of the header line. The
2499 white space that follows the newline must not be removed - it is part
2500 of the header. */
2501
2502 pp = recipient = store_get(ss - s + 1);
2503 for (p = s; p < ss; p++) if (*p != '\n') *pp++ = *p;
2504 *pp = 0;
2505
2506 #ifdef SUPPORT_I18N
2507 {
2508 BOOL b = allow_utf8_domains;
2509 allow_utf8_domains = TRUE;
2510 #endif
2511 recipient = parse_extract_address(recipient, &errmess, &start, &end,
2512 &domain, FALSE);
2513
2514 #ifdef SUPPORT_I18N
2515 if (string_is_utf8(recipient))
2516 message_smtputf8 = TRUE;
2517 else
2518 allow_utf8_domains = b;
2519 }
2520 #endif
2521
2522 /* Keep a list of all the bad addresses so we can send a single
2523 error message at the end. However, an empty address is not an error;
2524 just ignore it. This can come from an empty group list like
2525
2526 To: Recipients of list:;
2527
2528 If there are no recipients at all, an error will occur later. */
2529
2530 if (recipient == NULL && Ustrcmp(errmess, "empty address") != 0)
2531 {
2532 int len = Ustrlen(s);
2533 error_block *b = store_get(sizeof(error_block));
2534 while (len > 0 && isspace(s[len-1])) len--;
2535 b->next = NULL;
2536 b->text1 = string_printing(string_copyn(s, len));
2537 b->text2 = errmess;
2538 *bnext = b;
2539 bnext = &(b->next);
2540 }
2541
2542 /* If the recipient is already in the nonrecipients tree, it must
2543 have appeared on the command line with the option extract_addresses_
2544 remove_arguments set. Do not add it to the recipients, and keep a note
2545 that this has happened, in order to give a better error if there are
2546 no recipients left. */
2547
2548 else if (recipient != NULL)
2549 {
2550 if (tree_search(tree_nonrecipients, recipient) == NULL)
2551 receive_add_recipient(recipient, -1);
2552 else
2553 extracted_ignored = TRUE;
2554 }
2555
2556 /* Move on past this address */
2557
2558 s = ss + (*ss? 1:0);
2559 while (isspace(*s)) s++;
2560 } /* Next address */
2561
2562 f.parse_allow_group = FALSE; /* Reset group syntax flags */
2563 f.parse_found_group = FALSE;
2564
2565 /* If this was the bcc: header, mark it "old", which means it
2566 will be kept on the spool, but not transmitted as part of the
2567 message. */
2568
2569 if (h->type == htype_bcc) h->type = htype_old;
2570 } /* For appropriate header line */
2571 } /* For each header line */
2572
2573 }
2574
2575 /* Now build the unique message id. This has changed several times over the
2576 lifetime of Exim. This description was rewritten for Exim 4.14 (February 2003).
2577 Retaining all the history in the comment has become too unwieldy - read
2578 previous release sources if you want it.
2579
2580 The message ID has 3 parts: tttttt-pppppp-ss. Each part is a number in base 62.
2581 The first part is the current time, in seconds. The second part is the current
2582 pid. Both are large enough to hold 32-bit numbers in base 62. The third part
2583 can hold a number in the range 0-3843. It used to be a computed sequence
2584 number, but is now the fractional component of the current time in units of
2585 1/2000 of a second (i.e. a value in the range 0-1999). After a message has been
2586 received, Exim ensures that the timer has ticked at the appropriate level
2587 before proceeding, to avoid duplication if the pid happened to be re-used
2588 within the same time period. It seems likely that most messages will take at
2589 least half a millisecond to be received, so no delay will normally be
2590 necessary. At least for some time...
2591
2592 There is a modification when localhost_number is set. Formerly this was allowed
2593 to be as large as 255. Now it is restricted to the range 0-16, and the final
2594 component of the message id becomes (localhost_number * 200) + fractional time
2595 in units of 1/200 of a second (i.e. a value in the range 0-3399).
2596
2597 Some not-really-Unix operating systems use case-insensitive file names (Darwin,
2598 Cygwin). For these, we have to use base 36 instead of base 62. Luckily, this
2599 still allows the tttttt field to hold a large enough number to last for some
2600 more decades, and the final two-digit field can hold numbers up to 1295, which
2601 is enough for milliseconds (instead of 1/2000 of a second).
2602
2603 However, the pppppp field cannot hold a 32-bit pid, but it can hold a 31-bit
2604 pid, so it is probably safe because pids have to be positive. The
2605 localhost_number is restricted to 0-10 for these hosts, and when it is set, the
2606 final field becomes (localhost_number * 100) + fractional time in centiseconds.
2607
2608 Note that string_base62() returns its data in a static storage block, so it
2609 must be copied before calling string_base62() again. It always returns exactly
2610 6 characters.
2611
2612 There doesn't seem to be anything in the RFC which requires a message id to
2613 start with a letter, but Smail was changed to ensure this. The external form of
2614 the message id (as supplied by string expansion) therefore starts with an
2615 additional leading 'E'. The spool file names do not include this leading
2616 letter and it is not used internally.
2617
2618 NOTE: If ever the format of message ids is changed, the regular expression for
2619 checking that a string is in this format must be updated in a corresponding
2620 way. It appears in the initializing code in exim.c. The macro MESSAGE_ID_LENGTH
2621 must also be changed to reflect the correct string length. The queue-sort code
2622 needs to know the layout. Then, of course, other programs that rely on the
2623 message id format will need updating too. */
2624
2625 Ustrncpy(message_id, string_base62((long int)(message_id_tv.tv_sec)), 6);
2626 message_id[6] = '-';
2627 Ustrncpy(message_id + 7, string_base62((long int)getpid()), 6);
2628
2629 /* Deal with the case where the host number is set. The value of the number was
2630 checked when it was read, to ensure it isn't too big. The timing granularity is
2631 left in id_resolution so that an appropriate wait can be done after receiving
2632 the message, if necessary (we hope it won't be). */
2633
2634 if (host_number_string)
2635 {
2636 id_resolution = BASE_62 == 62 ? 5000 : 10000;
2637 sprintf(CS(message_id + MESSAGE_ID_LENGTH - 3), "-%2s",
2638 string_base62((long int)(
2639 host_number * (1000000/id_resolution) +
2640 message_id_tv.tv_usec/id_resolution)) + 4);
2641 }
2642
2643 /* Host number not set: final field is just the fractional time at an
2644 appropriate resolution. */
2645
2646 else
2647 {
2648 id_resolution = BASE_62 == 62 ? 500 : 1000;
2649 sprintf(CS(message_id + MESSAGE_ID_LENGTH - 3), "-%2s",
2650 string_base62((long int)(message_id_tv.tv_usec/id_resolution)) + 4);
2651 }
2652
2653 /* Add the current message id onto the current process info string if
2654 it will fit. */
2655
2656 (void)string_format(process_info + process_info_len,
2657 PROCESS_INFO_SIZE - process_info_len, " id=%s", message_id);
2658
2659 /* If we are using multiple input directories, set up the one for this message
2660 to be the least significant base-62 digit of the time of arrival. Otherwise
2661 ensure that it is an empty string. */
2662
2663 message_subdir[0] = split_spool_directory ? message_id[5] : 0;
2664
2665 /* Now that we have the message-id, if there is no message-id: header, generate
2666 one, but only for local (without suppress_local_fixups) or submission mode
2667 messages. This can be user-configured if required, but we had better flatten
2668 any illegal characters therein. */
2669
2670 if ( !msgid_header
2671 && ((!sender_host_address && !f.suppress_local_fixups) || f.submission_mode))
2672 {
2673 uschar *p;
2674 uschar *id_text = US"";
2675 uschar *id_domain = primary_hostname;
2676
2677 /* Permit only letters, digits, dots, and hyphens in the domain */
2678
2679 if (message_id_domain)
2680 {
2681 uschar *new_id_domain = expand_string(message_id_domain);
2682 if (!new_id_domain)
2683 {
2684 if (!f.expand_string_forcedfail)
2685 log_write(0, LOG_MAIN|LOG_PANIC,
2686 "expansion of \"%s\" (message_id_header_domain) "
2687 "failed: %s", message_id_domain, expand_string_message);
2688 }
2689 else if (*new_id_domain)
2690 {
2691 id_domain = new_id_domain;
2692 for (p = id_domain; *p; p++)
2693 if (!isalnum(*p) && *p != '.') *p = '-'; /* No need to test '-' ! */
2694 }
2695 }
2696
2697 /* Permit all characters except controls and RFC 2822 specials in the
2698 additional text part. */
2699
2700 if (message_id_text)
2701 {
2702 uschar *new_id_text = expand_string(message_id_text);
2703 if (!new_id_text)
2704 {
2705 if (!f.expand_string_forcedfail)
2706 log_write(0, LOG_MAIN|LOG_PANIC,
2707 "expansion of \"%s\" (message_id_header_text) "
2708 "failed: %s", message_id_text, expand_string_message);
2709 }
2710 else if (*new_id_text)
2711 {
2712 id_text = new_id_text;
2713 for (p = id_text; *p; p++) if (mac_iscntrl_or_special(*p)) *p = '-';
2714 }
2715 }
2716
2717 /* Add the header line
2718 * Resent-* headers are prepended, per RFC 5322 3.6.6. Non-Resent-* are
2719 * appended, to preserve classical expectations of header ordering. */
2720
2721 header_add_at_position(!resents_exist, NULL, FALSE, htype_id,
2722 "%sMessage-Id: <%s%s%s@%s>\n", resent_prefix, message_id_external,
2723 (*id_text == 0)? "" : ".", id_text, id_domain);
2724 }
2725
2726 /* If we are to log recipients, keep a copy of the raw ones before any possible
2727 rewriting. Must copy the count, because later ACLs and the local_scan()
2728 function may mess with the real recipients. */
2729
2730 if (LOGGING(received_recipients))
2731 {
2732 raw_recipients = store_get(recipients_count * sizeof(uschar *));
2733 for (i = 0; i < recipients_count; i++)
2734 raw_recipients[i] = string_copy(recipients_list[i].address);
2735 raw_recipients_count = recipients_count;
2736 }
2737
2738 /* Ensure the recipients list is fully qualified and rewritten. Unqualified
2739 recipients will get here only if the conditions were right (allow_unqualified_
2740 recipient is TRUE). */
2741
2742 for (i = 0; i < recipients_count; i++)
2743 recipients_list[i].address =
2744 rewrite_address(recipients_list[i].address, TRUE, TRUE,
2745 global_rewrite_rules, rewrite_existflags);
2746
2747 /* If there is no From: header, generate one for local (without
2748 suppress_local_fixups) or submission_mode messages. If there is no sender
2749 address, but the sender is local or this is a local delivery error, use the
2750 originator login. This shouldn't happen for genuine bounces, but might happen
2751 for autoreplies. The addition of From: must be done *before* checking for the
2752 possible addition of a Sender: header, because untrusted_set_sender allows an
2753 untrusted user to set anything in the envelope (which might then get info
2754 From:) but we still want to ensure a valid Sender: if it is required. */
2755
2756 if ( !from_header
2757 && ((!sender_host_address && !f.suppress_local_fixups) || f.submission_mode))
2758 {
2759 uschar *oname = US"";
2760
2761 /* Use the originator_name if this is a locally submitted message and the
2762 caller is not trusted. For trusted callers, use it only if -F was used to
2763 force its value or if we have a non-SMTP message for which -f was not used
2764 to set the sender. */
2765
2766 if (!sender_host_address)
2767 {
2768 if (!f.trusted_caller || f.sender_name_forced ||
2769 (!smtp_input && !f.sender_address_forced))
2770 oname = originator_name;
2771 }
2772
2773 /* For non-locally submitted messages, the only time we use the originator
2774 name is when it was forced by the /name= option on control=submission. */
2775
2776 else if (submission_name) oname = submission_name;
2777
2778 /* Envelope sender is empty */
2779
2780 if (!*sender_address)
2781 {
2782 uschar *fromstart, *fromend;
2783
2784 fromstart = string_sprintf("%sFrom: %s%s",
2785 resent_prefix, oname, *oname ? " <" : "");
2786 fromend = *oname ? US">" : US"";
2787
2788 if (f.sender_local || f.local_error_message)
2789 header_add(htype_from, "%s%s@%s%s\n", fromstart,
2790 local_part_quote(originator_login), qualify_domain_sender,
2791 fromend);
2792
2793 else if (f.submission_mode && authenticated_id)
2794 {
2795 if (!submission_domain)
2796 header_add(htype_from, "%s%s@%s%s\n", fromstart,
2797 local_part_quote(authenticated_id), qualify_domain_sender,
2798 fromend);
2799
2800 else if (!*submission_domain) /* empty => whole address set */
2801 header_add(htype_from, "%s%s%s\n", fromstart, authenticated_id,
2802 fromend);
2803
2804 else
2805 header_add(htype_from, "%s%s@%s%s\n", fromstart,
2806 local_part_quote(authenticated_id), submission_domain, fromend);
2807
2808 from_header = header_last; /* To get it checked for Sender: */
2809 }
2810 }
2811
2812 /* There is a non-null envelope sender. Build the header using the original
2813 sender address, before any rewriting that might have been done while
2814 verifying it. */
2815
2816 else
2817 {
2818 header_add(htype_from, "%sFrom: %s%s%s%s\n", resent_prefix,
2819 oname,
2820 *oname ? " <" : "",
2821 sender_address_unrewritten ? sender_address_unrewritten : sender_address,
2822 *oname ? ">" : "");
2823
2824 from_header = header_last; /* To get it checked for Sender: */
2825 }
2826 }
2827
2828
2829 /* If the sender is local (without suppress_local_fixups), or if we are in
2830 submission mode and there is an authenticated_id, check that an existing From:
2831 is correct, and if not, generate a Sender: header, unless disabled. Any
2832 previously-existing Sender: header was removed above. Note that sender_local,
2833 as well as being TRUE if the caller of exim is not trusted, is also true if a
2834 trusted caller did not supply a -f argument for non-smtp input. To allow
2835 trusted callers to forge From: without supplying -f, we have to test explicitly
2836 here. If the From: header contains more than one address, then the call to
2837 parse_extract_address fails, and a Sender: header is inserted, as required. */
2838
2839 if ( from_header
2840 && ( f.active_local_from_check
2841 && ( f.sender_local && !f.trusted_caller && !f.suppress_local_fixups
2842 || f.submission_mode && authenticated_id
2843 ) ) )
2844 {
2845 BOOL make_sender = TRUE;
2846 int start, end, domain;
2847 uschar *errmess;
2848 uschar *from_address =
2849 parse_extract_address(Ustrchr(from_header->text, ':') + 1, &errmess,
2850 &start, &end, &domain, FALSE);
2851 uschar *generated_sender_address;
2852
2853 generated_sender_address = f.submission_mode
2854 ? !submission_domain
2855 ? string_sprintf("%s@%s",
2856 local_part_quote(authenticated_id), qualify_domain_sender)
2857 : !*submission_domain /* empty => full address */
2858 ? string_sprintf("%s", authenticated_id)
2859 : string_sprintf("%s@%s",
2860 local_part_quote(authenticated_id), submission_domain)
2861 : string_sprintf("%s@%s",
2862 local_part_quote(originator_login), qualify_domain_sender);
2863
2864 /* Remove permitted prefixes and suffixes from the local part of the From:
2865 address before doing the comparison with the generated sender. */
2866
2867 if (from_address)
2868 {
2869 int slen;
2870 uschar *at = domain ? from_address + domain - 1 : NULL;
2871
2872 if (at) *at = 0;
2873 from_address += route_check_prefix(from_address, local_from_prefix);
2874 slen = route_check_suffix(from_address, local_from_suffix);
2875 if (slen > 0)
2876 {
2877 memmove(from_address+slen, from_address, Ustrlen(from_address)-slen);
2878 from_address += slen;
2879 }
2880 if (at) *at = '@';
2881
2882 if ( strcmpic(generated_sender_address, from_address) == 0
2883 || (!domain && strcmpic(from_address, originator_login) == 0))
2884 make_sender = FALSE;
2885 }
2886
2887 /* We have to cause the Sender header to be rewritten if there are
2888 appropriate rewriting rules. */
2889
2890 if (make_sender)
2891 if (f.submission_mode && !submission_name)
2892 header_add(htype_sender, "%sSender: %s\n", resent_prefix,
2893 generated_sender_address);
2894 else
2895 header_add(htype_sender, "%sSender: %s <%s>\n",
2896 resent_prefix,
2897 f.submission_mode ? submission_name : originator_name,
2898 generated_sender_address);
2899
2900 /* Ensure that a non-null envelope sender address corresponds to the
2901 submission mode sender address. */
2902
2903 if (f.submission_mode && *sender_address)
2904 {
2905 if (!sender_address_unrewritten)
2906 sender_address_unrewritten = sender_address;
2907 sender_address = generated_sender_address;
2908 if (Ustrcmp(sender_address_unrewritten, generated_sender_address) != 0)
2909 log_write(L_address_rewrite, LOG_MAIN,
2910 "\"%s\" from env-from rewritten as \"%s\" by submission mode",
2911 sender_address_unrewritten, generated_sender_address);
2912 }
2913 }
2914
2915 /* If there are any rewriting rules, apply them to the sender address, unless
2916 it has already been rewritten as part of verification for SMTP input. */
2917
2918 if (global_rewrite_rules && !sender_address_unrewritten && *sender_address)
2919 {
2920 sender_address = rewrite_address(sender_address, FALSE, TRUE,
2921 global_rewrite_rules, rewrite_existflags);
2922 DEBUG(D_receive|D_rewrite)
2923 debug_printf("rewritten sender = %s\n", sender_address);
2924 }
2925
2926
2927 /* The headers must be run through rewrite_header(), because it ensures that
2928 addresses are fully qualified, as well as applying any rewriting rules that may
2929 exist.
2930
2931 Qualification of header addresses in a message from a remote host happens only
2932 if the host is in sender_unqualified_hosts or recipient_unqualified hosts, as
2933 appropriate. For local messages, qualification always happens, unless -bnq is
2934 used to explicitly suppress it. No rewriting is done for an unqualified address
2935 that is left untouched.
2936
2937 We start at the second header, skipping our own Received:. This rewriting is
2938 documented as happening *after* recipient addresses are taken from the headers
2939 by the -t command line option. An added Sender: gets rewritten here. */
2940
2941 for (h = header_list->next; h; h = h->next)
2942 {
2943 header_line *newh = rewrite_header(h, NULL, NULL, global_rewrite_rules,
2944 rewrite_existflags, TRUE);
2945 if (newh) h = newh;
2946 }
2947
2948
2949 /* An RFC 822 (sic) message is not legal unless it has at least one of "to",
2950 "cc", or "bcc". Note that although the minimal examples in RFC 822 show just
2951 "to" or "bcc", the full syntax spec allows "cc" as well. If any resent- header
2952 exists, this applies to the set of resent- headers rather than the normal set.
2953
2954 The requirement for a recipient header has been removed in RFC 2822. At this
2955 point in the code, earlier versions of Exim added a To: header for locally
2956 submitted messages, and an empty Bcc: header for others. In the light of the
2957 changes in RFC 2822, this was dropped in November 2003. */
2958
2959
2960 /* If there is no date header, generate one if the message originates locally
2961 (i.e. not over TCP/IP) and suppress_local_fixups is not set, or if the
2962 submission mode flag is set. Messages without Date: are not valid, but it seems
2963 to be more confusing if Exim adds one to all remotely-originated messages.
2964 As per Message-Id, we prepend if resending, else append.
2965 */
2966
2967 if ( !date_header_exists
2968 && ((!sender_host_address && !f.suppress_local_fixups) || f.submission_mode))
2969 header_add_at_position(!resents_exist, NULL, FALSE, htype_other,
2970 "%sDate: %s\n", resent_prefix, tod_stamp(tod_full));
2971
2972 search_tidyup(); /* Free any cached resources */
2973
2974 /* Show the complete set of headers if debugging. Note that the first one (the
2975 new Received:) has not yet been set. */
2976
2977 DEBUG(D_receive)
2978 {
2979 debug_printf(">>Headers after rewriting and local additions:\n");
2980 for (h = header_list->next; h; h = h->next)
2981 debug_printf("%c %s", h->type, h->text);
2982 debug_printf("\n");
2983 }
2984
2985 /* The headers are now complete in store. If we are running in filter
2986 testing mode, that is all this function does. Return TRUE if the message
2987 ended with a dot. */
2988
2989 if (filter_test != FTEST_NONE)
2990 {
2991 process_info[process_info_len] = 0;
2992 return message_ended == END_DOT;
2993 }
2994
2995 /*XXX CHUNKING: need to cancel cutthrough under BDAT, for now. In future,
2996 think more if it could be handled. Cannot do onward CHUNKING unless
2997 inbound is, but inbound chunking ought to be ok with outbound plain.
2998 Could we do onward CHUNKING given inbound CHUNKING?
2999 */
3000 if (chunking_state > CHUNKING_OFFERED)
3001 cancel_cutthrough_connection(FALSE, US"chunking active");
3002
3003 /* Cutthrough delivery:
3004 We have to create the Received header now rather than at the end of reception,
3005 so the timestamp behaviour is a change to the normal case.
3006 Having created it, send the headers to the destination. */
3007
3008 if (cutthrough.cctx.sock >= 0 && cutthrough.delivery)
3009 {
3010 if (received_count > received_headers_max)
3011 {
3012 cancel_cutthrough_connection(TRUE, US"too many headers");
3013 if (smtp_input) receive_swallow_smtp(); /* Swallow incoming SMTP */
3014 log_write(0, LOG_MAIN|LOG_REJECT, "rejected from <%s>%s%s%s%s: "
3015 "Too many \"Received\" headers",
3016 sender_address,
3017 sender_fullhost ? "H=" : "", sender_fullhost ? sender_fullhost : US"",
3018 sender_ident ? "U=" : "", sender_ident ? sender_ident : US"");
3019 message_id[0] = 0; /* Indicate no message accepted */
3020 smtp_reply = US"550 Too many \"Received\" headers - suspected mail loop";
3021 goto TIDYUP; /* Skip to end of function */
3022 }
3023 received_header_gen();
3024 add_acl_headers(ACL_WHERE_RCPT, US"MAIL or RCPT");
3025 (void) cutthrough_headers_send();
3026 }
3027
3028
3029 /* Open a new spool file for the data portion of the message. We need
3030 to access it both via a file descriptor and a stream. Try to make the
3031 directory if it isn't there. */
3032
3033 spool_name = spool_fname(US"input", message_subdir, message_id, US"-D");
3034 DEBUG(D_receive) debug_printf("Data file name: %s\n", spool_name);
3035
3036 if ((data_fd = Uopen(spool_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE)) < 0)
3037 {
3038 if (errno == ENOENT)
3039 {
3040 (void) directory_make(spool_directory,
3041 spool_sname(US"input", message_subdir),
3042 INPUT_DIRECTORY_MODE, TRUE);
3043 data_fd = Uopen(spool_name, O_RDWR|O_CREAT|O_EXCL, SPOOL_MODE);
3044 }
3045 if (data_fd < 0)
3046 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Failed to create spool file %s: %s",
3047 spool_name, strerror(errno));
3048 }
3049
3050 /* Make sure the file's group is the Exim gid, and double-check the mode
3051 because the group setting doesn't always get set automatically. */
3052
3053 if (fchown(data_fd, exim_uid, exim_gid))
3054 log_write(0, LOG_MAIN|LOG_PANIC_DIE,
3055 "Failed setting ownership on spool file %s: %s",
3056 spool_name, strerror(errno));
3057 (void)fchmod(data_fd, SPOOL_MODE);
3058
3059 /* We now have data file open. Build a stream for it and lock it. We lock only
3060 the first line of the file (containing the message ID) because otherwise there
3061 are problems when Exim is run under Cygwin (I'm told). See comments in
3062 spool_in.c, where the same locking is done. */
3063
3064 spool_data_file = fdopen(data_fd, "w+");
3065 lock_data.l_type = F_WRLCK;
3066 lock_data.l_whence = SEEK_SET;
3067 lock_data.l_start = 0;
3068 lock_data.l_len = SPOOL_DATA_START_OFFSET;
3069
3070 if (fcntl(data_fd, F_SETLK, &lock_data) < 0)
3071 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Cannot lock %s (%d): %s", spool_name,
3072 errno, strerror(errno));
3073
3074 /* We have an open, locked data file. Write the message id to it to make it
3075 self-identifying. Then read the remainder of the input of this message and
3076 write it to the data file. If the variable next != NULL, it contains the first
3077 data line (which was read as a header but then turned out not to have the right
3078 format); write it (remembering that it might contain binary zeros). The result
3079 of fwrite() isn't inspected; instead we call ferror() below. */
3080
3081 fprintf(spool_data_file, "%s-D\n", message_id);
3082 if (next)
3083 {
3084 uschar *s = next->text;
3085 int len = next->slen;
3086 if (fwrite(s, 1, len, spool_data_file) == len) /* "if" for compiler quietening */
3087 body_linecount++; /* Assumes only 1 line */
3088 }
3089
3090 /* Note that we might already be at end of file, or the logical end of file
3091 (indicated by '.'), or might have encountered an error while writing the
3092 message id or "next" line. */
3093
3094 if (!ferror(spool_data_file) && !(receive_feof)() && message_ended != END_DOT)
3095 {
3096 if (smtp_input)
3097 {
3098 message_ended = chunking_state <= CHUNKING_OFFERED
3099 ? read_message_data_smtp(spool_data_file)
3100 : spool_wireformat
3101 ? read_message_bdat_smtp_wire(spool_data_file)
3102 : read_message_bdat_smtp(spool_data_file);
3103 receive_linecount++; /* The terminating "." line */
3104 }
3105 else
3106 message_ended = read_message_data(spool_data_file);
3107
3108 receive_linecount += body_linecount; /* For BSMTP errors mainly */
3109 message_linecount += body_linecount;
3110
3111 switch (message_ended)
3112 {
3113 /* Handle premature termination of SMTP */
3114
3115 case END_EOF:
3116 if (smtp_input)
3117 {
3118 Uunlink(spool_name); /* Lose data file when closed */
3119 cancel_cutthrough_connection(TRUE, US"sender closed connection");
3120 message_id[0] = 0; /* Indicate no message accepted */
3121 smtp_reply = handle_lost_connection(US"");
3122 smtp_yield = FALSE;
3123 goto TIDYUP; /* Skip to end of function */
3124 }
3125 break;
3126
3127 /* Handle message that is too big. Don't use host_or_ident() in the log
3128 message; we want to see the ident value even for non-remote messages. */
3129
3130 case END_SIZE:
3131 Uunlink(spool_name); /* Lose the data file when closed */
3132 cancel_cutthrough_connection(TRUE, US"mail too big");
3133 if (smtp_input) receive_swallow_smtp(); /* Swallow incoming SMTP */
3134
3135 log_write(L_size_reject, LOG_MAIN|LOG_REJECT, "rejected from <%s>%s%s%s%s: "
3136 "message too big: read=%d max=%d",
3137 sender_address,
3138 sender_fullhost ? " H=" : "",
3139 sender_fullhost ? sender_fullhost : US"",
3140 sender_ident ? " U=" : "",
3141 sender_ident ? sender_ident : US"",
3142 message_size,
3143 thismessage_size_limit);
3144
3145 if (smtp_input)
3146 {
3147 smtp_reply = US"552 Message size exceeds maximum permitted";
3148 message_id[0] = 0; /* Indicate no message accepted */
3149 goto TIDYUP; /* Skip to end of function */
3150 }
3151 else
3152 {
3153 fseek(spool_data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3154 give_local_error(ERRMESS_TOOBIG,
3155 string_sprintf("message too big (max=%d)", thismessage_size_limit),
3156 US"message rejected: ", error_rc, spool_data_file, header_list);
3157 /* Does not return */
3158 }
3159 break;
3160
3161 /* Handle bad BDAT protocol sequence */
3162
3163 case END_PROTOCOL:
3164 Uunlink(spool_name); /* Lose the data file when closed */
3165 cancel_cutthrough_connection(TRUE, US"sender protocol error");
3166 smtp_reply = US""; /* Response already sent */
3167 message_id[0] = 0; /* Indicate no message accepted */
3168 goto TIDYUP; /* Skip to end of function */
3169 }
3170 }
3171
3172 /* Restore the standard SIGALRM handler for any subsequent processing. (For
3173 example, there may be some expansion in an ACL that uses a timer.) */
3174
3175 os_non_restarting_signal(SIGALRM, sigalrm_handler);
3176
3177 /* The message body has now been read into the data file. Call fflush() to
3178 empty the buffers in C, and then call fsync() to get the data written out onto
3179 the disk, as fflush() doesn't do this (or at least, it isn't documented as
3180 having to do this). If there was an I/O error on either input or output,
3181 attempt to send an error message, and unlink the spool file. For non-SMTP input
3182 we can then give up. Note that for SMTP input we must swallow the remainder of
3183 the input in cases of output errors, since the far end doesn't expect to see
3184 anything until the terminating dot line is sent. */
3185
3186 if (fflush(spool_data_file) == EOF || ferror(spool_data_file) ||
3187 EXIMfsync(fileno(spool_data_file)) < 0 || (receive_ferror)())
3188 {
3189 uschar *msg_errno = US strerror(errno);
3190 BOOL input_error = (receive_ferror)() != 0;
3191 uschar *msg = string_sprintf("%s error (%s) while receiving message from %s",
3192 input_error? "Input read" : "Spool write",
3193 msg_errno,
3194 sender_fullhost ? sender_fullhost : sender_ident);
3195
3196 log_write(0, LOG_MAIN, "Message abandoned: %s", msg);
3197 Uunlink(spool_name); /* Lose the data file */
3198 cancel_cutthrough_connection(TRUE, US"error writing spoolfile");
3199
3200 if (smtp_input)
3201 {
3202 if (input_error)
3203 smtp_reply = US"451 Error while reading input data";
3204 else
3205 {
3206 smtp_reply = US"451 Error while writing spool file";
3207 receive_swallow_smtp();
3208 }
3209 message_id[0] = 0; /* Indicate no message accepted */
3210 goto TIDYUP; /* Skip to end of function */
3211 }
3212
3213 else
3214 {
3215 fseek(spool_data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3216 give_local_error(ERRMESS_IOERR, msg, US"", error_rc, spool_data_file,
3217 header_list);
3218 /* Does not return */
3219 }
3220 }
3221
3222
3223 /* No I/O errors were encountered while writing the data file. */
3224
3225 DEBUG(D_receive) debug_printf("Data file written for message %s\n", message_id);
3226 if (LOGGING(receive_time)) timesince(&received_time_taken, &received_time);
3227
3228
3229 /* If there were any bad addresses extracted by -t, or there were no recipients
3230 left after -t, send a message to the sender of this message, or write it to
3231 stderr if the error handling option is set that way. Note that there may
3232 legitimately be no recipients for an SMTP message if they have all been removed
3233 by "discard".
3234
3235 We need to rewind the data file in order to read it. In the case of no
3236 recipients or stderr error writing, throw the data file away afterwards, and
3237 exit. (This can't be SMTP, which always ensures there's at least one
3238 syntactically good recipient address.) */
3239
3240 if (extract_recip && (bad_addresses || recipients_count == 0))
3241 {
3242 DEBUG(D_receive)
3243 {
3244 if (recipients_count == 0) debug_printf("*** No recipients\n");
3245 if (bad_addresses)
3246 {
3247 error_block *eblock = bad_addresses;
3248 debug_printf("*** Bad address(es)\n");
3249 while (eblock != NULL)
3250 {
3251 debug_printf(" %s: %s\n", eblock->text1, eblock->text2);
3252 eblock = eblock->next;
3253 }
3254 }
3255 }
3256
3257 fseek(spool_data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3258
3259 /* If configured to send errors to the sender, but this fails, force
3260 a failure error code. We use a special one for no recipients so that it
3261 can be detected by the autoreply transport. Otherwise error_rc is set to
3262 errors_sender_rc, which is EXIT_FAILURE unless -oee was given, in which case
3263 it is EXIT_SUCCESS. */
3264
3265 if (error_handling == ERRORS_SENDER)
3266 {
3267 if (!moan_to_sender(
3268 (bad_addresses == NULL)?
3269 (extracted_ignored? ERRMESS_IGADDRESS : ERRMESS_NOADDRESS) :
3270 (recipients_list == NULL)? ERRMESS_BADNOADDRESS : ERRMESS_BADADDRESS,
3271 bad_addresses, header_list, spool_data_file, FALSE))
3272 error_rc = (bad_addresses == NULL)? EXIT_NORECIPIENTS : EXIT_FAILURE;
3273 }
3274 else
3275 {
3276 if (!bad_addresses)
3277 if (extracted_ignored)
3278 fprintf(stderr, "exim: all -t recipients overridden by command line\n");
3279 else
3280 fprintf(stderr, "exim: no recipients in message\n");
3281 else
3282 {
3283 fprintf(stderr, "exim: invalid address%s",
3284 bad_addresses->next ? "es:\n" : ":");
3285 for ( ; bad_addresses; bad_addresses = bad_addresses->next)
3286 fprintf(stderr, " %s: %s\n", bad_addresses->text1,
3287 bad_addresses->text2);
3288 }
3289 }
3290
3291 if (recipients_count == 0 || error_handling == ERRORS_STDERR)
3292 {
3293 Uunlink(spool_name);
3294 (void)fclose(spool_data_file);
3295 exim_exit(error_rc, US"receiving");
3296 }
3297 }
3298
3299 /* Data file successfully written. Generate text for the Received: header by
3300 expanding the configured string, and adding a timestamp. By leaving this
3301 operation till now, we ensure that the timestamp is the time that message
3302 reception was completed. However, this is deliberately done before calling the
3303 data ACL and local_scan().
3304
3305 This Received: header may therefore be inspected by the data ACL and by code in
3306 the local_scan() function. When they have run, we update the timestamp to be
3307 the final time of reception.
3308
3309 If there is just one recipient, set up its value in the $received_for variable
3310 for use when we generate the Received: header.
3311
3312 Note: the checking for too many Received: headers is handled by the delivery
3313 code. */
3314 /*XXX eventually add excess Received: check for cutthrough case back when classifying them */
3315
3316 if (!received_header->text) /* Non-cutthrough case */
3317 {
3318 received_header_gen();
3319
3320 /* Set the value of message_body_size for the DATA ACL and for local_scan() */
3321
3322 message_body_size = (fstat(data_fd, &statbuf) == 0)?
3323 statbuf.st_size - SPOOL_DATA_START_OFFSET : -1;
3324
3325 /* If an ACL from any RCPT commands set up any warning headers to add, do so
3326 now, before running the DATA ACL. */
3327
3328 add_acl_headers(ACL_WHERE_RCPT, US"MAIL or RCPT");
3329 }
3330 else
3331 message_body_size = (fstat(data_fd, &statbuf) == 0)?
3332 statbuf.st_size - SPOOL_DATA_START_OFFSET : -1;
3333
3334 /* If an ACL is specified for checking things at this stage of reception of a
3335 message, run it, unless all the recipients were removed by "discard" in earlier
3336 ACLs. That is the only case in which recipients_count can be zero at this
3337 stage. Set deliver_datafile to point to the data file so that $message_body and
3338 $message_body_end can be extracted if needed. Allow $recipients in expansions.
3339 */
3340
3341 deliver_datafile = data_fd;
3342 user_msg = NULL;
3343
3344 f.enable_dollar_recipients = TRUE;
3345
3346 if (recipients_count == 0)
3347 blackholed_by = f.recipients_discarded ? US"MAIL ACL" : US"RCPT ACL";
3348
3349 else
3350 {
3351 /* Handle interactive SMTP messages */
3352
3353 if (smtp_input && !smtp_batched_input)
3354 {
3355
3356 #ifndef DISABLE_DKIM
3357 if (!f.dkim_disable_verify)
3358 {
3359 /* Finish verification */
3360 dkim_exim_verify_finish();
3361
3362 /* Check if we must run the DKIM ACL */
3363 if (acl_smtp_dkim && dkim_verify_signers && *dkim_verify_signers)
3364 {
3365 uschar * dkim_verify_signers_expanded =
3366 expand_string(dkim_verify_signers);
3367 gstring * results = NULL;
3368 int signer_sep = 0;
3369 const uschar * ptr;
3370 uschar * item;
3371 gstring * seen_items = NULL;
3372 int old_pool = store_pool;
3373
3374 store_pool = POOL_PERM; /* Allow created variables to live to data ACL */
3375
3376 if (!(ptr = dkim_verify_signers_expanded))
3377 log_write(0, LOG_MAIN|LOG_PANIC,
3378 "expansion of dkim_verify_signers option failed: %s",
3379 expand_string_message);
3380
3381 /* Default to OK when no items are present */
3382 rc = OK;
3383 while ((item = string_nextinlist(&ptr, &signer_sep, NULL, 0)))
3384 {
3385 /* Prevent running ACL for an empty item */
3386 if (!item || !*item) continue;
3387
3388 /* Only run ACL once for each domain or identity,
3389 no matter how often it appears in the expanded list. */
3390 if (seen_items)
3391 {
3392 uschar * seen_item;
3393 const uschar * seen_items_list = string_from_gstring(seen_items);
3394 int seen_sep = ':';
3395 BOOL seen_this_item = FALSE;
3396
3397 while ((seen_item = string_nextinlist(&seen_items_list, &seen_sep,
3398 NULL, 0)))
3399 if (Ustrcmp(seen_item,item) == 0)
3400 {
3401 seen_this_item = TRUE;
3402 break;
3403 }
3404
3405 if (seen_this_item)
3406 {
3407 DEBUG(D_receive)
3408 debug_printf("acl_smtp_dkim: skipping signer %s, "
3409 "already seen\n", item);
3410 continue;
3411 }
3412
3413 seen_items = string_catn(seen_items, US":", 1);
3414 }
3415 seen_items = string_cat(seen_items, item);
3416
3417 rc = dkim_exim_acl_run(item, &results, &user_msg, &log_msg);
3418 if (rc != OK)
3419 {
3420 DEBUG(D_receive)
3421 debug_printf("acl_smtp_dkim: acl_check returned %d on %s, "
3422 "skipping remaining items\n", rc, item);
3423 cancel_cutthrough_connection(TRUE, US"dkim acl not ok");
3424 break;
3425 }
3426 }
3427 dkim_verify_status = string_from_gstring(results);
3428 store_pool = old_pool;
3429 add_acl_headers(ACL_WHERE_DKIM, US"DKIM");
3430 if (rc == DISCARD)
3431 {
3432 recipients_count = 0;
3433 blackholed_by = US"DKIM ACL";
3434 if (log_msg)
3435 blackhole_log_msg = string_sprintf(": %s", log_msg);
3436 }
3437 else if (rc != OK)
3438 {
3439 Uunlink(spool_name);
3440 if (smtp_handle_acl_fail(ACL_WHERE_DKIM, rc, user_msg, log_msg) != 0)
3441 smtp_yield = FALSE; /* No more messages after dropped connection */
3442 smtp_reply = US""; /* Indicate reply already sent */
3443 message_id[0] = 0; /* Indicate no message accepted */
3444 goto TIDYUP; /* Skip to end of function */
3445 }
3446 }
3447 else
3448 dkim_exim_verify_log_all();
3449 }
3450 #endif /* DISABLE_DKIM */
3451
3452 #ifdef WITH_CONTENT_SCAN
3453 if ( recipients_count > 0
3454 && acl_smtp_mime
3455 && !run_mime_acl(acl_smtp_mime, &smtp_yield, &smtp_reply, &blackholed_by)
3456 )
3457 goto TIDYUP;
3458 #endif /* WITH_CONTENT_SCAN */
3459
3460 #ifdef EXPERIMENTAL_DMARC
3461 dmarc_up = dmarc_store_data(from_header);
3462 #endif /* EXPERIMENTAL_DMARC */
3463
3464 #ifndef DISABLE_PRDR
3465 if (prdr_requested && recipients_count > 1 && acl_smtp_data_prdr)
3466 {
3467 unsigned int c;
3468 int all_pass = OK;
3469 int all_fail = FAIL;
3470
3471 smtp_printf("353 PRDR content analysis beginning\r\n", TRUE);
3472 /* Loop through recipients, responses must be in same order received */
3473 for (c = 0; recipients_count > c; c++)
3474 {
3475 uschar * addr= recipients_list[c].address;
3476 uschar * msg= US"PRDR R=<%s> %s";
3477 uschar * code;
3478 DEBUG(D_receive)
3479 debug_printf("PRDR processing recipient %s (%d of %d)\n",
3480 addr, c+1, recipients_count);
3481 rc = acl_check(ACL_WHERE_PRDR, addr,
3482 acl_smtp_data_prdr, &user_msg, &log_msg);
3483
3484 /* If any recipient rejected content, indicate it in final message */
3485 all_pass |= rc;
3486 /* If all recipients rejected, indicate in final message */
3487 all_fail &= rc;
3488
3489 switch (rc)
3490 {
3491 case OK: case DISCARD: code = US"250"; break;
3492 case DEFER: code = US"450"; break;
3493 default: code = US"550"; break;
3494 }
3495 if (user_msg != NULL)
3496 smtp_user_msg(code, user_msg);
3497 else
3498 {
3499 switch (rc)
3500 {
3501 case OK: case DISCARD:
3502 msg = string_sprintf(CS msg, addr, "acceptance"); break;
3503 case DEFER:
3504 msg = string_sprintf(CS msg, addr, "temporary refusal"); break;
3505 default:
3506 msg = string_sprintf(CS msg, addr, "refusal"); break;
3507 }
3508 smtp_user_msg(code, msg);
3509 }
3510 if (log_msg) log_write(0, LOG_MAIN, "PRDR %s %s", addr, log_msg);
3511 else if (user_msg) log_write(0, LOG_MAIN, "PRDR %s %s", addr, user_msg);
3512 else log_write(0, LOG_MAIN, "%s", CS msg);
3513
3514 if (rc != OK) { receive_remove_recipient(addr); c--; }
3515 }
3516 /* Set up final message, used if data acl gives OK */
3517 smtp_reply = string_sprintf("%s id=%s message %s",
3518 all_fail == FAIL ? US"550" : US"250",
3519 message_id,
3520 all_fail == FAIL
3521 ? US"rejected for all recipients"
3522 : all_pass == OK
3523 ? US"accepted"
3524 : US"accepted for some recipients");
3525 if (recipients_count == 0)
3526 {
3527 message_id[0] = 0; /* Indicate no message accepted */
3528 goto TIDYUP;
3529 }
3530 }
3531 else
3532 prdr_requested = FALSE;
3533 #endif /* !DISABLE_PRDR */
3534
3535 /* Check the recipients count again, as the MIME ACL might have changed
3536 them. */
3537
3538 if (acl_smtp_data != NULL && recipients_count > 0)
3539 {
3540 rc = acl_check(ACL_WHERE_DATA, NULL, acl_smtp_data, &user_msg, &log_msg);
3541 add_acl_headers(ACL_WHERE_DATA, US"DATA");
3542 if (rc == DISCARD)
3543 {
3544 recipients_count = 0;
3545 blackholed_by = US"DATA ACL";
3546 if (log_msg)
3547 blackhole_log_msg = string_sprintf(": %s", log_msg);
3548 cancel_cutthrough_connection(TRUE, US"data acl discard");
3549 }
3550 else if (rc != OK)
3551 {
3552 Uunlink(spool_name);
3553 cancel_cutthrough_connection(TRUE, US"data acl not ok");
3554 #ifdef WITH_CONTENT_SCAN
3555 unspool_mbox();
3556 #endif
3557 #ifdef EXPERIMENTAL_DCC
3558 dcc_ok = 0;
3559 #endif
3560 if (smtp_handle_acl_fail(ACL_WHERE_DATA, rc, user_msg, log_msg) != 0)
3561 smtp_yield = FALSE; /* No more messages after dropped connection */
3562 smtp_reply = US""; /* Indicate reply already sent */
3563 message_id[0] = 0; /* Indicate no message accepted */
3564 goto TIDYUP; /* Skip to end of function */
3565 }
3566 }
3567 }
3568
3569 /* Handle non-SMTP and batch SMTP (i.e. non-interactive) messages. Note that
3570 we cannot take different actions for permanent and temporary rejections. */
3571
3572 else
3573 {
3574
3575 #ifdef WITH_CONTENT_SCAN
3576 if ( acl_not_smtp_mime
3577 && !run_mime_acl(acl_not_smtp_mime, &smtp_yield, &smtp_reply,
3578 &blackholed_by)
3579 )
3580 goto TIDYUP;
3581 #endif /* WITH_CONTENT_SCAN */
3582
3583 if (acl_not_smtp)
3584 {
3585 uschar *user_msg, *log_msg;
3586 f.authentication_local = TRUE;
3587 rc = acl_check(ACL_WHERE_NOTSMTP, NULL, acl_not_smtp, &user_msg, &log_msg);
3588 if (rc == DISCARD)
3589 {
3590 recipients_count = 0;
3591 blackholed_by = US"non-SMTP ACL";
3592 if (log_msg)
3593 blackhole_log_msg = string_sprintf(": %s", log_msg);
3594 }
3595 else if (rc != OK)
3596 {
3597 Uunlink(spool_name);
3598 #ifdef WITH_CONTENT_SCAN
3599 unspool_mbox();
3600 #endif
3601 #ifdef EXPERIMENTAL_DCC
3602 dcc_ok = 0;
3603 #endif
3604 /* The ACL can specify where rejections are to be logged, possibly
3605 nowhere. The default is main and reject logs. */
3606
3607 if (log_reject_target)
3608 log_write(0, log_reject_target, "F=<%s> rejected by non-SMTP ACL: %s",
3609 sender_address, log_msg);
3610
3611 if (!user_msg) user_msg = US"local configuration problem";
3612 if (smtp_batched_input)
3613 moan_smtp_batch(NULL, "%d %s", 550, user_msg);
3614 /* Does not return */
3615 else
3616 {
3617 fseek(spool_data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3618 give_local_error(ERRMESS_LOCAL_ACL, user_msg,
3619 US"message rejected by non-SMTP ACL: ", error_rc, spool_data_file,
3620 header_list);
3621 /* Does not return */
3622 }
3623 }
3624 add_acl_headers(ACL_WHERE_NOTSMTP, US"non-SMTP");
3625 }
3626 }
3627
3628 /* The applicable ACLs have been run */
3629
3630 if (f.deliver_freeze) frozen_by = US"ACL"; /* for later logging */
3631 if (f.queue_only_policy) queued_by = US"ACL";
3632 }
3633
3634 #ifdef WITH_CONTENT_SCAN
3635 unspool_mbox();
3636 #endif
3637
3638 #ifdef EXPERIMENTAL_DCC
3639 dcc_ok = 0;
3640 #endif
3641
3642
3643 #ifdef HAVE_LOCAL_SCAN
3644 /* The final check on the message is to run the scan_local() function. The
3645 version supplied with Exim always accepts, but this is a hook for sysadmins to
3646 supply their own checking code. The local_scan() function is run even when all
3647 the recipients have been discarded. */
3648
3649 lseek(data_fd, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3650
3651 /* Arrange to catch crashes in local_scan(), so that the -D file gets
3652 deleted, and the incident gets logged. */
3653
3654 if (sigsetjmp(local_scan_env, 1) == 0)
3655 {
3656 had_local_scan_crash = 0;
3657 os_non_restarting_signal(SIGSEGV, local_scan_crash_handler);
3658 os_non_restarting_signal(SIGFPE, local_scan_crash_handler);
3659 os_non_restarting_signal(SIGILL, local_scan_crash_handler);
3660 os_non_restarting_signal(SIGBUS, local_scan_crash_handler);
3661
3662 DEBUG(D_receive) debug_printf("calling local_scan(); timeout=%d\n",
3663 local_scan_timeout);
3664 local_scan_data = NULL;
3665
3666 had_local_scan_timeout = 0;
3667 os_non_restarting_signal(SIGALRM, local_scan_timeout_handler);
3668 if (local_scan_timeout > 0) ALARM(local_scan_timeout);
3669 rc = local_scan(data_fd, &local_scan_data);
3670 ALARM_CLR(0);
3671 os_non_restarting_signal(SIGALRM, sigalrm_handler);
3672
3673 f.enable_dollar_recipients = FALSE;
3674
3675 store_pool = POOL_MAIN; /* In case changed */
3676 DEBUG(D_receive) debug_printf("local_scan() returned %d %s\n", rc,
3677 local_scan_data);
3678
3679 os_non_restarting_signal(SIGSEGV, SIG_DFL);
3680 os_non_restarting_signal(SIGFPE, SIG_DFL);
3681 os_non_restarting_signal(SIGILL, SIG_DFL);
3682 os_non_restarting_signal(SIGBUS, SIG_DFL);
3683 }
3684 else
3685 {
3686 if (had_local_scan_crash)
3687 {
3688 log_write(0, LOG_MAIN|LOG_REJECT, "local_scan() function crashed with "
3689 "signal %d - message temporarily rejected (size %d)",
3690 had_local_scan_crash, message_size);
3691 receive_bomb_out(US"local-scan-error", US"local verification problem");
3692 /* Does not return */
3693 }
3694 if (had_local_scan_timeout)
3695 {
3696 log_write(0, LOG_MAIN|LOG_REJECT, "local_scan() function timed out - "
3697 "message temporarily rejected (size %d)", message_size);
3698 receive_bomb_out(US"local-scan-timeout", US"local verification problem");
3699 /* Does not return */
3700 }
3701 }
3702
3703 /* The length check is paranoia against some runaway code, and also because
3704 (for a success return) lines in the spool file are read into big_buffer. */
3705
3706 if (local_scan_data)
3707 {
3708 int len = Ustrlen(local_scan_data);
3709 if (len > LOCAL_SCAN_MAX_RETURN) len = LOCAL_SCAN_MAX_RETURN;
3710 local_scan_data = string_copyn(local_scan_data, len);
3711 }
3712
3713 if (rc == LOCAL_SCAN_ACCEPT_FREEZE)
3714 {
3715 if (!f.deliver_freeze) /* ACL might have already frozen */
3716 {
3717 f.deliver_freeze = TRUE;
3718 deliver_frozen_at = time(NULL);
3719 frozen_by = US"local_scan()";
3720 }
3721 rc = LOCAL_SCAN_ACCEPT;
3722 }
3723 else if (rc == LOCAL_SCAN_ACCEPT_QUEUE)
3724 {
3725 if (!f.queue_only_policy) /* ACL might have already queued */
3726 {
3727 f.queue_only_policy = TRUE;
3728 queued_by = US"local_scan()";
3729 }
3730 rc = LOCAL_SCAN_ACCEPT;
3731 }
3732
3733 /* Message accepted: remove newlines in local_scan_data because otherwise
3734 the spool file gets corrupted. Ensure that all recipients are qualified. */
3735
3736 if (rc == LOCAL_SCAN_ACCEPT)
3737 {
3738 if (local_scan_data)
3739 {
3740 uschar *s;
3741 for (s = local_scan_data; *s != 0; s++) if (*s == '\n') *s = ' ';
3742 }
3743 for (i = 0; i < recipients_count; i++)
3744 {
3745 recipient_item *r = recipients_list + i;
3746 r->address = rewrite_address_qualify(r->address, TRUE);
3747 if (r->errors_to != NULL)
3748 r->errors_to = rewrite_address_qualify(r->errors_to, TRUE);
3749 }
3750 if (recipients_count == 0 && blackholed_by == NULL)
3751 blackholed_by = US"local_scan";
3752 }
3753
3754 /* Message rejected: newlines permitted in local_scan_data to generate
3755 multiline SMTP responses. */
3756
3757 else
3758 {
3759 uschar *istemp = US"";
3760 uschar *smtp_code;
3761 gstring * g;
3762
3763 errmsg = local_scan_data;
3764
3765 Uunlink(spool_name); /* Cancel this message */
3766 switch(rc)
3767 {
3768 default:
3769 log_write(0, LOG_MAIN, "invalid return %d from local_scan(). Temporary "
3770 "rejection given", rc);
3771 goto TEMPREJECT;
3772
3773 case LOCAL_SCAN_REJECT_NOLOGHDR:
3774 BIT_CLEAR(log_selector, log_selector_size, Li_rejected_header);
3775 /* Fall through */
3776
3777 case LOCAL_SCAN_REJECT:
3778 smtp_code = US"550";
3779 if (!errmsg) errmsg = US"Administrative prohibition";
3780 break;
3781
3782 case LOCAL_SCAN_TEMPREJECT_NOLOGHDR:
3783 BIT_CLEAR(log_selector, log_selector_size, Li_rejected_header);
3784 /* Fall through */
3785
3786 case LOCAL_SCAN_TEMPREJECT:
3787 TEMPREJECT:
3788 smtp_code = US"451";
3789 if (!errmsg) errmsg = US"Temporary local problem";
3790 istemp = US"temporarily ";
3791 break;
3792 }
3793
3794 g = string_append(NULL, 2, US"F=",
3795 sender_address[0] == 0 ? US"<>" : sender_address);
3796 g = add_host_info_for_log(g);
3797
3798 log_write(0, LOG_MAIN|LOG_REJECT, "%s %srejected by local_scan(): %.256s",
3799 string_from_gstring(g), istemp, string_printing(errmsg));
3800
3801 if (smtp_input)
3802 {
3803 if (!smtp_batched_input)
3804 {
3805 smtp_respond(smtp_code, 3, TRUE, errmsg);
3806 message_id[0] = 0; /* Indicate no message accepted */
3807 smtp_reply = US""; /* Indicate reply already sent */
3808 goto TIDYUP; /* Skip to end of function */
3809 }
3810 else
3811 moan_smtp_batch(NULL, "%s %s", smtp_code, errmsg);
3812 /* Does not return */
3813 }
3814 else
3815 {
3816 fseek(spool_data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3817 give_local_error(ERRMESS_LOCAL_SCAN, errmsg,
3818 US"message rejected by local scan code: ", error_rc, spool_data_file,
3819 header_list);
3820 /* Does not return */
3821 }
3822 }
3823
3824 /* Reset signal handlers to ignore signals that previously would have caused
3825 the message to be abandoned. */
3826
3827 signal(SIGTERM, SIG_IGN);
3828 signal(SIGINT, SIG_IGN);
3829 #endif /* HAVE_LOCAL_SCAN */
3830
3831
3832 /* Ensure the first time flag is set in the newly-received message. */
3833
3834 f.deliver_firsttime = TRUE;
3835
3836 #ifdef EXPERIMENTAL_BRIGHTMAIL
3837 if (bmi_run == 1)
3838 { /* rewind data file */
3839 lseek(data_fd, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3840 bmi_verdicts = bmi_process_message(header_list, data_fd);
3841 }
3842 #endif
3843
3844 /* Update the timestamp in our Received: header to account for any time taken by
3845 an ACL or by local_scan(). The new time is the time that all reception
3846 processing is complete. */
3847
3848 timestamp = expand_string(US"${tod_full}");
3849 tslen = Ustrlen(timestamp);
3850
3851 memcpy(received_header->text + received_header->slen - tslen - 1,
3852 timestamp, tslen);
3853
3854 /* In MUA wrapper mode, ignore queueing actions set by ACL or local_scan() */
3855
3856 if (mua_wrapper)
3857 {
3858 f.deliver_freeze = FALSE;
3859 f.queue_only_policy = FALSE;
3860 }
3861
3862 /* Keep the data file open until we have written the header file, in order to
3863 hold onto the lock. In a -bh run, or if the message is to be blackholed, we
3864 don't write the header file, and we unlink the data file. If writing the header
3865 file fails, we have failed to accept this message. */
3866
3867 if (host_checking || blackholed_by)
3868 {
3869 header_line *h;
3870 Uunlink(spool_name);
3871 msg_size = 0; /* Compute size for log line */
3872 for (h = header_list; h; h = h->next)
3873 if (h->type != '*') msg_size += h->slen;
3874 }
3875
3876 /* Write the -H file */
3877
3878 else
3879 if ((msg_size = spool_write_header(message_id, SW_RECEIVING, &errmsg)) < 0)
3880 {
3881 log_write(0, LOG_MAIN, "Message abandoned: %s", errmsg);
3882 Uunlink(spool_name); /* Lose the data file */
3883
3884 if (smtp_input)
3885 {
3886 smtp_reply = US"451 Error in writing spool file";
3887 message_id[0] = 0; /* Indicate no message accepted */
3888 goto TIDYUP;
3889 }
3890 else
3891 {
3892 fseek(spool_data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3893 give_local_error(ERRMESS_IOERR, errmsg, US"", error_rc, spool_data_file,
3894 header_list);
3895 /* Does not return */
3896 }
3897 }
3898
3899
3900 /* The message has now been successfully received. */
3901
3902 receive_messagecount++;
3903
3904 /* Add data size to written header size. We do not count the initial file name
3905 that is in the file, but we do add one extra for the notional blank line that
3906 precedes the data. This total differs from message_size in that it include the
3907 added Received: header and any other headers that got created locally. */
3908
3909 if (fflush(spool_data_file))
3910 {
3911 errmsg = string_sprintf("Spool write error: %s", strerror(errno));
3912 log_write(0, LOG_MAIN, "%s\n", errmsg);
3913 Uunlink(spool_name); /* Lose the data file */
3914
3915 if (smtp_input)
3916 {
3917 smtp_reply = US"451 Error in writing spool file";
3918 message_id[0] = 0; /* Indicate no message accepted */
3919 goto TIDYUP;
3920 }
3921 else
3922 {
3923 fseek(spool_data_file, (long int)SPOOL_DATA_START_OFFSET, SEEK_SET);
3924 give_local_error(ERRMESS_IOERR, errmsg, US"", error_rc, spool_data_file,
3925 header_list);
3926 /* Does not return */
3927 }
3928 }
3929 fstat(data_fd, &statbuf);
3930
3931 msg_size += statbuf.st_size - SPOOL_DATA_START_OFFSET + 1;
3932
3933 /* Generate a "message received" log entry. We do this by building up a dynamic
3934 string as required. We log the arrival of a new message while the
3935 file is still locked, just in case the machine is *really* fast, and delivers
3936 it first! Include any message id that is in the message - since the syntax of a
3937 message id is actually an addr-spec, we can use the parse routine to canonicalize
3938 it. */
3939
3940 g = string_get(256);
3941
3942 g = string_append(g, 2,
3943 fake_response == FAIL ? US"(= " : US"<= ",
3944 sender_address[0] == 0 ? US"<>" : sender_address);
3945 if (message_reference)
3946 g = string_append(g, 2, US" R=", message_reference);
3947
3948 g = add_host_info_for_log(g);
3949
3950 #ifdef SUPPORT_TLS
3951 if (LOGGING(tls_cipher) && tls_in.cipher)
3952 g = string_append(g, 2, US" X=", tls_in.cipher);
3953 if (LOGGING(tls_certificate_verified) && tls_in.cipher)
3954 g = string_append(g, 2, US" CV=", tls_in.certificate_verified ? "yes":"no");
3955 if (LOGGING(tls_peerdn) && tls_in.peerdn)
3956 g = string_append(g, 3, US" DN=\"", string_printing(tls_in.peerdn), US"\"");
3957 if (LOGGING(tls_sni) && tls_in.sni)
3958 g = string_append(g, 3, US" SNI=\"", string_printing(tls_in.sni), US"\"");
3959 #endif
3960
3961 if (sender_host_authenticated)
3962 {
3963 g = string_append(g, 2, US" A=", sender_host_authenticated);
3964 if (authenticated_id)
3965 {
3966 g = string_append(g, 2, US":", authenticated_id);
3967 if (LOGGING(smtp_mailauth) && authenticated_sender)
3968 g = string_append(g, 2, US":", authenticated_sender);
3969 }
3970 }
3971
3972 #ifndef DISABLE_PRDR
3973 if (prdr_requested)
3974 g = string_catn(g, US" PRDR", 5);
3975 #endif
3976
3977 #ifdef SUPPORT_PROXY
3978 if (proxy_session && LOGGING(proxy))
3979 g = string_append(g, 2, US" PRX=", proxy_local_address);
3980 #endif
3981
3982 if (chunking_state > CHUNKING_OFFERED)
3983 g = string_catn(g, US" K", 2);
3984
3985 sprintf(CS big_buffer, "%d", msg_size);
3986 g = string_append(g, 2, US" S=", big_buffer);
3987
3988 /* log 8BITMIME mode announced in MAIL_FROM
3989 0 ... no BODY= used
3990 7 ... 7BIT
3991 8 ... 8BITMIME */
3992 if (LOGGING(8bitmime))
3993 {
3994 sprintf(CS big_buffer, "%d", body_8bitmime);
3995 g = string_append(g, 2, US" M8S=", big_buffer);
3996 }
3997
3998 #ifndef DISABLE_DKIM
3999 if (LOGGING(dkim) && dkim_verify_overall)
4000 g = string_append(g, 2, US" DKIM=", dkim_verify_overall);
4001 # ifdef EXPERIMENTAL_ARC
4002 if (LOGGING(dkim) && arc_state && Ustrcmp(arc_state, "pass") == 0)
4003 g = string_catn(g, US" ARC", 4);
4004 # endif
4005 #endif
4006
4007 if (LOGGING(receive_time))
4008 g = string_append(g, 2, US" RT=", string_timediff(&received_time_taken));
4009
4010 if (*queue_name)
4011 g = string_append(g, 2, US" Q=", queue_name);
4012
4013 /* If an addr-spec in a message-id contains a quoted string, it can contain
4014 any characters except " \ and CR and so in particular it can contain NL!
4015 Therefore, make sure we use a printing-characters only version for the log.
4016 Also, allow for domain literals in the message id. */
4017
4018 if (msgid_header)
4019 {
4020 uschar *old_id;
4021 BOOL save_allow_domain_literals = allow_domain_literals;
4022 allow_domain_literals = TRUE;
4023 old_id = parse_extract_address(Ustrchr(msgid_header->text, ':') + 1,
4024 &errmsg, &start, &end, &domain, FALSE);
4025 allow_domain_literals = save_allow_domain_literals;
4026 if (old_id != NULL)
4027 g = string_append(g, 2, US" id=", string_printing(old_id));
4028 }
4029
4030 /* If subject logging is turned on, create suitable printing-character
4031 text. By expanding $h_subject: we make use of the MIME decoding. */
4032
4033 if (LOGGING(subject) && subject_header)
4034 {
4035 int i;
4036 uschar *p = big_buffer;
4037 uschar *ss = expand_string(US"$h_subject:");
4038
4039 /* Backslash-quote any double quotes or backslashes so as to make a
4040 a C-like string, and turn any non-printers into escape sequences. */
4041
4042 *p++ = '\"';
4043 if (*ss != 0) for (i = 0; i < 100 && ss[i] != 0; i++)
4044 {
4045 if (ss[i] == '\"' || ss[i] == '\\') *p++ = '\\';
4046 *p++ = ss[i];
4047 }
4048 *p++ = '\"';
4049 *p = 0;
4050 g = string_append(g, 2, US" T=", string_printing(big_buffer));
4051 }
4052
4053 /* Terminate the string: string_cat() and string_append() leave room, but do
4054 not put the zero in. */
4055
4056 (void) string_from_gstring(g);
4057
4058 /* Create a message log file if message logs are being used and this message is
4059 not blackholed. Write the reception stuff to it. We used to leave message log
4060 creation until the first delivery, but this has proved confusing for some
4061 people. */
4062
4063 if (message_logs && !blackholed_by)
4064 {
4065 int fd;
4066 uschar * m_name = spool_fname(US"msglog", message_subdir, message_id, US"");
4067
4068 if ( (fd = Uopen(m_name, O_WRONLY|O_APPEND|O_CREAT, SPOOL_MODE)) < 0
4069 && errno == ENOENT
4070 )
4071 {