1 /* $Cambridge: exim/src/src/transport.c,v 1.20 2007/09/28 12:21:57 tom Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2007 */
8 /* See the file NOTICE for conditions of use and distribution. */
10 /* General functions concerned with transportation, and generic options for all
16 #ifdef HAVE_LINUX_SENDFILE
17 #include <sys/sendfile.h>
20 /* Structure for keeping list of addresses that have been added to
21 Envelope-To:, in order to avoid duplication. */
29 /* Static data for write_chunk() */
31 static uschar *chunk_ptr; /* chunk pointer */
32 static uschar *nl_check; /* string to look for at line start */
33 static int nl_check_length; /* length of same */
34 static uschar *nl_escape; /* string to insert */
35 static int nl_escape_length; /* length of same */
36 static int nl_partial_match; /* length matched at chunk end */
39 /* Generic options for transports, all of which live inside transport_instance
40 data blocks and which therefore have the opt_public flag set. Note that there
41 are other options living inside this structure which can be set only from
42 certain transports. */
44 optionlist optionlist_transports[] = {
45 { "*expand_group", opt_stringptr|opt_hidden|opt_public,
46 (void *)offsetof(transport_instance, expand_gid) },
47 { "*expand_user", opt_stringptr|opt_hidden|opt_public,
48 (void *)offsetof(transport_instance, expand_uid) },
49 { "*headers_rewrite_flags", opt_int|opt_public|opt_hidden,
50 (void *)offsetof(transport_instance, rewrite_existflags) },
51 { "*headers_rewrite_rules", opt_void|opt_public|opt_hidden,
52 (void *)offsetof(transport_instance, rewrite_rules) },
53 { "*set_group", opt_bool|opt_hidden|opt_public,
54 (void *)offsetof(transport_instance, gid_set) },
55 { "*set_user", opt_bool|opt_hidden|opt_public,
56 (void *)offsetof(transport_instance, uid_set) },
57 { "body_only", opt_bool|opt_public,
58 (void *)offsetof(transport_instance, body_only) },
59 { "current_directory", opt_stringptr|opt_public,
60 (void *)offsetof(transport_instance, current_dir) },
61 { "debug_print", opt_stringptr | opt_public,
62 (void *)offsetof(transport_instance, debug_string) },
63 { "delivery_date_add", opt_bool|opt_public,
64 (void *)(offsetof(transport_instance, delivery_date_add)) },
65 { "disable_logging", opt_bool|opt_public,
66 (void *)(offsetof(transport_instance, disable_logging)) },
67 { "driver", opt_stringptr|opt_public,
68 (void *)offsetof(transport_instance, driver_name) },
69 { "envelope_to_add", opt_bool|opt_public,
70 (void *)(offsetof(transport_instance, envelope_to_add)) },
71 { "group", opt_expand_gid|opt_public,
72 (void *)offsetof(transport_instance, gid) },
73 { "headers_add", opt_stringptr|opt_public,
74 (void *)offsetof(transport_instance, add_headers) },
75 { "headers_only", opt_bool|opt_public,
76 (void *)offsetof(transport_instance, headers_only) },
77 { "headers_remove", opt_stringptr|opt_public,
78 (void *)offsetof(transport_instance, remove_headers) },
79 { "headers_rewrite", opt_rewrite|opt_public,
80 (void *)offsetof(transport_instance, headers_rewrite) },
81 { "home_directory", opt_stringptr|opt_public,
82 (void *)offsetof(transport_instance, home_dir) },
83 { "initgroups", opt_bool|opt_public,
84 (void *)offsetof(transport_instance, initgroups) },
85 { "message_size_limit", opt_stringptr|opt_public,
86 (void *)offsetof(transport_instance, message_size_limit) },
87 { "rcpt_include_affixes", opt_bool|opt_public,
88 (void *)offsetof(transport_instance, rcpt_include_affixes) },
89 { "retry_use_local_part", opt_bool|opt_public,
90 (void *)offsetof(transport_instance, retry_use_local_part) },
91 { "return_path", opt_stringptr|opt_public,
92 (void *)(offsetof(transport_instance, return_path)) },
93 { "return_path_add", opt_bool|opt_public,
94 (void *)(offsetof(transport_instance, return_path_add)) },
95 { "shadow_condition", opt_stringptr|opt_public,
96 (void *)offsetof(transport_instance, shadow_condition) },
97 { "shadow_transport", opt_stringptr|opt_public,
98 (void *)offsetof(transport_instance, shadow) },
99 { "transport_filter", opt_stringptr|opt_public,
100 (void *)offsetof(transport_instance, filter_command) },
101 { "transport_filter_timeout", opt_time|opt_public,
102 (void *)offsetof(transport_instance, filter_timeout) },
103 { "user", opt_expand_uid|opt_public,
104 (void *)offsetof(transport_instance, uid) }
107 int optionlist_transports_size =
108 sizeof(optionlist_transports)/sizeof(optionlist);
111 /*************************************************
112 * Initialize transport list *
113 *************************************************/
115 /* Read the transports section of the configuration file, and set up a chain of
116 transport instances according to its contents. Each transport has generic
117 options and may also have its own private options. This function is only ever
118 called when transports == NULL. We use generic code in readconf to do most of
124 transport_instance *t;
126 readconf_driver_init(US"transport",
127 (driver_instance **)(&transports), /* chain anchor */
128 (driver_info *)transports_available, /* available drivers */
129 sizeof(transport_info), /* size of info block */
130 &transport_defaults, /* default values for generic options */
131 sizeof(transport_instance), /* size of instance block */
132 optionlist_transports, /* generic options */
133 optionlist_transports_size);
135 /* Now scan the configured transports and check inconsistencies. A shadow
136 transport is permitted only for local transports. */
138 for (t = transports; t != NULL; t = t->next)
142 if (t->shadow != NULL)
143 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
144 "shadow transport not allowed on non-local transport %s", t->name);
147 if (t->body_only && t->headers_only)
148 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
149 "%s transport: body_only and headers_only are mutually exclusive",
156 /*************************************************
157 * Write block of data *
158 *************************************************/
160 /* Subroutine called by write_chunk() and at the end of the message actually
161 to write a data block. Also called directly by some transports to write
162 additional data to the file descriptor (e.g. prefix, suffix).
164 If a transport wants data transfers to be timed, it sets a non-zero value in
165 transport_write_timeout. A non-zero transport_write_timeout causes a timer to
166 be set for each block of data written from here. If time runs out, then write()
167 fails and provokes an error return. The caller can then inspect sigalrm_seen to
170 On some systems, if a quota is exceeded during the write, the yield is the
171 number of bytes written rather than an immediate error code. This also happens
172 on some systems in other cases, for example a pipe that goes away because the
173 other end's process terminates (Linux). On other systems, (e.g. Solaris 2) you
174 get the error codes the first time.
176 The write() function is also interruptible; the Solaris 2.6 man page says:
178 If write() is interrupted by a signal before it writes any
179 data, it will return -1 with errno set to EINTR.
181 If write() is interrupted by a signal after it successfully
182 writes some data, it will return the number of bytes written.
184 To handle these cases, we want to restart the write() to output the remainder
185 of the data after a non-negative return from write(), except after a timeout.
186 In the error cases (EDQUOT, EPIPE) no bytes get written the second time, and a
187 proper error then occurs. In principle, after an interruption, the second
188 write() could suffer the same fate, but we do not want to continue for
189 evermore, so stick a maximum repetition count on the loop to act as a
193 fd file descriptor to write to
194 block block of bytes to write
195 len number of bytes to write
197 Returns: TRUE on success, FALSE on failure (with errno preserved);
198 transport_count is incremented by the number of bytes written
202 transport_write_block(int fd, uschar *block, int len)
204 int i, rc, save_errno;
205 int local_timeout = transport_write_timeout;
207 /* This loop is for handling incomplete writes and other retries. In most
208 normal cases, it is only ever executed once. */
210 for (i = 0; i < 100; i++)
213 debug_printf("writing data block fd=%d size=%d timeout=%d\n",
214 fd, len, local_timeout);
216 /* This code makes use of alarm() in order to implement the timeout. This
217 isn't a very tidy way of doing things. Using non-blocking I/O with select()
218 provides a neater approach. However, I don't know how to do this when TLS is
221 if (transport_write_timeout <= 0) /* No timeout wanted */
224 if (tls_active == fd) rc = tls_write(block, len); else
226 rc = write(fd, block, len);
230 /* Timeout wanted. */
234 alarm(local_timeout);
236 if (tls_active == fd) rc = tls_write(block, len); else
238 rc = write(fd, block, len);
240 local_timeout = alarm(0);
248 /* Hopefully, the most common case is success, so test that first. */
250 if (rc == len) { transport_count += len; return TRUE; }
252 /* A non-negative return code is an incomplete write. Try again for the rest
253 of the block. If we have exactly hit the timeout, give up. */
259 transport_count += rc;
260 DEBUG(D_transport) debug_printf("write incomplete (%d)\n", rc);
261 goto CHECK_TIMEOUT; /* A few lines below */
264 /* A negative return code with an EINTR error is another form of
265 incomplete write, zero bytes having been written */
267 if (save_errno == EINTR)
270 debug_printf("write interrupted before anything written\n");
271 goto CHECK_TIMEOUT; /* A few lines below */
274 /* A response of EAGAIN from write() is likely only in the case of writing
275 to a FIFO that is not swallowing the data as fast as Exim is writing it. */
277 if (save_errno == EAGAIN)
280 debug_printf("write temporarily locked out, waiting 1 sec\n");
283 /* Before continuing to try another write, check that we haven't run out of
287 if (transport_write_timeout > 0 && local_timeout <= 0)
295 /* Otherwise there's been an error */
297 DEBUG(D_transport) debug_printf("writing error %d: %s\n", save_errno,
298 strerror(save_errno));
303 /* We've tried and tried and tried but still failed */
305 errno = ERRNO_WRITEINCOMPLETE;
312 /*************************************************
313 * Write formatted string *
314 *************************************************/
316 /* This is called by various transports. It is a convenience function.
321 ... arguments for format
323 Returns: the yield of transport_write_block()
327 transport_write_string(int fd, char *format, ...)
330 va_start(ap, format);
331 if (!string_vformat(big_buffer, big_buffer_size, format, ap))
332 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong formatted string in transport");
334 return transport_write_block(fd, big_buffer, Ustrlen(big_buffer));
340 /*************************************************
341 * Write character chunk *
342 *************************************************/
344 /* Subroutine used by transport_write_message() to scan character chunks for
345 newlines and act appropriately. The object is to minimise the number of writes.
346 The output byte stream is buffered up in deliver_out_buffer, which is written
347 only when it gets full, thus minimizing write operations and TCP packets.
349 Static data is used to handle the case when the last character of the previous
350 chunk was NL, or matched part of the data that has to be escaped.
353 fd file descript to write to
354 chunk pointer to data to write
355 len length of data to write
356 usr_crlf TRUE if CR LF is wanted at the end of each line
358 In addition, the static nl_xxx variables must be set as required.
360 Returns: TRUE on success, FALSE on failure (with errno preserved)
364 write_chunk(int fd, uschar *chunk, int len, BOOL use_crlf)
366 uschar *start = chunk;
367 uschar *end = chunk + len;
368 register uschar *ptr;
369 int mlen = DELIVER_OUT_BUFFER_SIZE - nl_escape_length - 2;
371 /* The assumption is made that the check string will never stretch over move
372 than one chunk since the only time there are partial matches is when copying
373 the body in large buffers. There is always enough room in the buffer for an
374 escape string, since the loop below ensures this for each character it
375 processes, and it won't have stuck in the escape string if it left a partial
378 if (nl_partial_match >= 0)
380 if (nl_check_length > 0 && len >= nl_check_length &&
381 Ustrncmp(start, nl_check + nl_partial_match,
382 nl_check_length - nl_partial_match) == 0)
384 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
385 chunk_ptr += nl_escape_length;
386 start += nl_check_length - nl_partial_match;
389 /* The partial match was a false one. Insert the characters carried over
390 from the previous chunk. */
392 else if (nl_partial_match > 0)
394 Ustrncpy(chunk_ptr, nl_check, nl_partial_match);
395 chunk_ptr += nl_partial_match;
398 nl_partial_match = -1;
401 /* Now process the characters in the chunk. Whenever we hit a newline we check
402 for possible escaping. The code for the non-NL route should be as fast as
405 for (ptr = start; ptr < end; ptr++)
409 /* Flush the buffer if it has reached the threshold - we want to leave enough
410 room for the next uschar, plus a possible extra CR for an LF, plus the escape
413 if (chunk_ptr - deliver_out_buffer > mlen)
415 if (!transport_write_block(fd, deliver_out_buffer,
416 chunk_ptr - deliver_out_buffer))
418 chunk_ptr = deliver_out_buffer;
421 if ((ch = *ptr) == '\n')
423 int left = end - ptr - 1; /* count of chars left after NL */
425 /* Insert CR before NL if required */
427 if (use_crlf) *chunk_ptr++ = '\r';
430 /* The check_string test (formerly "from hack") replaces the specific
431 string at the start of a line with an escape string (e.g. "From " becomes
432 ">From " or "." becomes "..". It is a case-sensitive test. The length
433 check above ensures there is always enough room to insert this string. */
435 if (nl_check_length > 0)
437 if (left >= nl_check_length &&
438 Ustrncmp(ptr+1, nl_check, nl_check_length) == 0)
440 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
441 chunk_ptr += nl_escape_length;
442 ptr += nl_check_length;
445 /* Handle the case when there isn't enough left to match the whole
446 check string, but there may be a partial match. We remember how many
447 characters matched, and finish processing this chunk. */
449 else if (left <= 0) nl_partial_match = 0;
451 else if (Ustrncmp(ptr+1, nl_check, left) == 0)
453 nl_partial_match = left;
459 /* Not a NL character */
461 else *chunk_ptr++ = ch;
470 /*************************************************
471 * Generate address for RCPT TO *
472 *************************************************/
474 /* This function puts together an address for RCPT to, using the caseful
475 version of the local part and the caseful version of the domain. If there is no
476 prefix or suffix, or if affixes are to be retained, we can just use the
477 original address. Otherwise, if there is a prefix but no suffix we can use a
478 pointer into the original address. If there is a suffix, however, we have to
482 addr the address item
483 include_affixes TRUE if affixes are to be included
489 transport_rcpt_address(address_item *addr, BOOL include_affixes)
496 setflag(addr, af_include_affixes); /* Affects logged => line */
497 return addr->address;
500 if (addr->suffix == NULL)
502 if (addr->prefix == NULL) return addr->address;
503 return addr->address + Ustrlen(addr->prefix);
506 at = Ustrrchr(addr->address, '@');
507 plen = (addr->prefix == NULL)? 0 : Ustrlen(addr->prefix);
508 slen = Ustrlen(addr->suffix);
510 return string_sprintf("%.*s@%s", (at - addr->address - plen - slen),
511 addr->address + plen, at + 1);
515 /*************************************************
516 * Output Envelope-To: address & scan duplicates *
517 *************************************************/
519 /* This function is called from internal_transport_write_message() below, when
520 generating an Envelope-To: header line. It checks for duplicates of the given
521 address and its ancestors. When one is found, this function calls itself
522 recursively, to output the envelope address of the duplicate.
524 We want to avoid duplication in the list, which can arise for example when
525 A->B,C and then both B and C alias to D. This can also happen when there are
526 unseen drivers in use. So a list of addresses that have been output is kept in
529 It is also possible to have loops in the address ancestry/duplication graph,
530 for example if there are two top level addresses A and B and we have A->B,C and
531 B->A. To break the loop, we use a list of processed addresses in the dlist
534 After handling duplication, this function outputs the progenitor of the given
538 p the address we are interested in
539 pplist address of anchor of the list of addresses not to output
540 pdlist address of anchor of the list of processed addresses
541 first TRUE if this is the first address; set it FALSE afterwards
542 fd the file descriptor to write to
543 use_crlf to be passed on to write_chunk()
545 Returns: FALSE if writing failed
549 write_env_to(address_item *p, struct aci **pplist, struct aci **pdlist,
550 BOOL *first, int fd, BOOL use_crlf)
555 /* Do nothing if we have already handled this address. If not, remember it
556 so that we don't handle it again. */
558 for (ppp = *pdlist; ppp != NULL; ppp = ppp->next)
559 { if (p == ppp->ptr) return TRUE; }
561 ppp = store_get(sizeof(struct aci));
566 /* Now scan up the ancestry, checking for duplicates at each generation. */
568 for (pp = p;; pp = pp->parent)
571 for (dup = addr_duplicate; dup != NULL; dup = dup->next)
573 if (dup->dupof != pp) continue; /* Not a dup of our address */
574 if (!write_env_to(dup, pplist, pdlist, first, fd, use_crlf)) return FALSE;
576 if (pp->parent == NULL) break;
579 /* Check to see if we have already output the progenitor. */
581 for (ppp = *pplist; ppp != NULL; ppp = ppp->next)
582 { if (pp == ppp->ptr) break; }
583 if (ppp != NULL) return TRUE;
585 /* Remember what we have output, and output it. */
587 ppp = store_get(sizeof(struct aci));
592 if (!(*first) && !write_chunk(fd, US",\n ", 3, use_crlf)) return FALSE;
594 return write_chunk(fd, pp->address, Ustrlen(pp->address), use_crlf);
600 /*************************************************
601 * Write the message *
602 *************************************************/
604 /* This function writes the message to the given file descriptor. The headers
605 are in the in-store data structure, and the rest of the message is in the open
606 file descriptor deliver_datafile. Make sure we start it at the beginning.
608 . If add_return_path is TRUE, a "return-path:" header is added to the message,
609 containing the envelope sender's address.
611 . If add_envelope_to is TRUE, a "envelope-to:" header is added to the message,
612 giving the top-level envelope address that caused this delivery to happen.
614 . If add_delivery_date is TRUE, a "delivery-date:" header is added to the
615 message. It gives the time and date that delivery took place.
617 . If check_string is not null, the start of each line is checked for that
618 string. If it is found, it is replaced by escape_string. This used to be
619 the "from hack" for files, and "smtp_dots" for escaping SMTP dots.
621 . If use_crlf is true, newlines are turned into CRLF (SMTP output).
623 The yield is TRUE if all went well, and FALSE if not. Exit *immediately* after
624 any writing or reading error, leaving the code in errno intact. Error exits
625 can include timeouts for certain transports, which are requested by setting
626 transport_write_timeout non-zero.
629 addr (chain of) addresses (for extra headers), or NULL;
630 only the first address is used
631 fd file descriptor to write the message to
632 options bit-wise options:
633 add_return_path if TRUE, add a "return-path" header
634 add_envelope_to if TRUE, add a "envelope-to" header
635 add_delivery_date if TRUE, add a "delivery-date" header
636 use_crlf if TRUE, turn NL into CR LF
637 end_dot if TRUE, send a terminating "." line at the end
638 no_headers if TRUE, omit the headers
639 no_body if TRUE, omit the body
640 size_limit if > 0, this is a limit to the size of message written;
641 it is used when returning messages to their senders,
642 and is approximate rather than exact, owing to chunk
644 add_headers a string containing one or more headers to add; it is
645 expanded, and must be in correct RFC 822 format as
646 it is transmitted verbatim; NULL => no additions,
647 and so does empty string or forced expansion fail
648 remove_headers a colon-separated list of headers to remove, or NULL
649 check_string a string to check for at the start of lines, or NULL
650 escape_string a string to insert in front of any check string
651 rewrite_rules chain of header rewriting rules
652 rewrite_existflags flags for the rewriting rules
654 Returns: TRUE on success; FALSE (with errno) on failure.
655 In addition, the global variable transport_count
656 is incremented by the number of bytes written.
660 internal_transport_write_message(address_item *addr, int fd, int options,
661 int size_limit, uschar *add_headers, uschar *remove_headers, uschar *check_string,
662 uschar *escape_string, rewrite_rule *rewrite_rules, int rewrite_existflags)
667 BOOL use_crlf = (options & topt_use_crlf) != 0;
669 /* Initialize pointer in output buffer. */
671 chunk_ptr = deliver_out_buffer;
673 /* Set up the data for start-of-line data checking and escaping */
675 nl_partial_match = -1;
676 if (check_string != NULL && escape_string != NULL)
678 nl_check = check_string;
679 nl_check_length = Ustrlen(nl_check);
680 nl_escape = escape_string;
681 nl_escape_length = Ustrlen(nl_escape);
683 else nl_check_length = nl_escape_length = 0;
685 /* Whether the escaping mechanism is applied to headers or not is controlled by
686 an option (set for SMTP, not otherwise). Negate the length if not wanted till
687 after the headers. */
689 if ((options & topt_escape_headers) == 0) nl_check_length = -nl_check_length;
691 /* Write the headers if required, including any that have to be added. If there
692 are header rewriting rules, apply them. */
694 if ((options & topt_no_headers) == 0)
696 /* Add return-path: if requested. */
698 if ((options & topt_add_return_path) != 0)
700 uschar buffer[ADDRESS_MAXLENGTH + 20];
701 sprintf(CS buffer, "Return-path: <%.*s>\n", ADDRESS_MAXLENGTH,
703 if (!write_chunk(fd, buffer, Ustrlen(buffer), use_crlf)) return FALSE;
706 /* Add envelope-to: if requested */
708 if ((options & topt_add_envelope_to) != 0)
712 struct aci *plist = NULL;
713 struct aci *dlist = NULL;
714 void *reset_point = store_get(0);
716 if (!write_chunk(fd, US"Envelope-to: ", 13, use_crlf)) return FALSE;
718 /* Pick up from all the addresses. The plist and dlist variables are
719 anchors for lists of addresses already handled; they have to be defined at
720 this level becuase write_env_to() calls itself recursively. */
722 for (p = addr; p != NULL; p = p->next)
724 if (!write_env_to(p, &plist, &dlist, &first, fd, use_crlf)) return FALSE;
727 /* Add a final newline and reset the store used for tracking duplicates */
729 if (!write_chunk(fd, US"\n", 1, use_crlf)) return FALSE;
730 store_reset(reset_point);
733 /* Add delivery-date: if requested. */
735 if ((options & topt_add_delivery_date) != 0)
738 sprintf(CS buffer, "Delivery-date: %s\n", tod_stamp(tod_full));
739 if (!write_chunk(fd, buffer, Ustrlen(buffer), use_crlf)) return FALSE;
742 /* Then the message's headers. Don't write any that are flagged as "old";
743 that means they were rewritten, or are a record of envelope rewriting, or
744 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
745 match any entries therein. Then check addr->p.remove_headers too, provided that
748 if (remove_headers != NULL)
750 uschar *s = expand_string(remove_headers);
751 if (s == NULL && !expand_string_forcedfail)
753 errno = ERRNO_CHHEADER_FAIL;
759 for (h = header_list; h != NULL; h = h->next)
765 if (h->type == htype_old) continue;
767 include_header = TRUE;
768 list = remove_headers;
770 for (i = 0; i < 2; i++) /* For remove_headers && addr->p.remove_headers */
774 int sep = ':'; /* This is specified as a colon-separated list */
777 while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer)))
780 int len = Ustrlen(s);
781 if (strncmpic(h->text, s, len) != 0) continue;
783 while (*ss == ' ' || *ss == '\t') ss++;
784 if (*ss == ':') break;
786 if (s != NULL) { include_header = FALSE; break; }
788 if (addr != NULL) list = addr->p.remove_headers;
791 /* If this header is to be output, try to rewrite it if there are rewriting
796 if (rewrite_rules != NULL)
798 void *reset_point = store_get(0);
800 rewrite_header(h, NULL, NULL, rewrite_rules, rewrite_existflags,
804 if (!write_chunk(fd, hh->text, hh->slen, use_crlf)) return FALSE;
805 store_reset(reset_point);
806 continue; /* With the next header line */
810 /* Either no rewriting rules, or it didn't get rewritten */
812 if (!write_chunk(fd, h->text, h->slen, use_crlf)) return FALSE;
819 DEBUG(D_transport) debug_printf("removed header line:\n%s---\n",
824 /* Add on any address-specific headers. If there are multiple addresses,
825 they will all have the same headers in order to be batched. The headers
826 are chained in reverse order of adding (so several addresses from the
827 same alias might share some of them) but we want to output them in the
828 opposite order. This is a bit tedious, but there shouldn't be very many
829 of them. We just walk the list twice, reversing the pointers each time,
830 but on the second time, write out the items.
832 Headers added to an address by a router are guaranteed to end with a newline.
838 header_line *hprev = addr->p.extra_headers;
840 for (i = 0; i < 2; i++)
842 for (h = hprev, hprev = NULL; h != NULL; h = hnext)
849 if (!write_chunk(fd, h->text, h->slen, use_crlf)) return FALSE;
851 debug_printf("added header line(s):\n%s---\n", h->text);
857 /* If a string containing additional headers exists, expand it and write
858 out the result. This is done last so that if it (deliberately or accidentally)
859 isn't in header format, it won't mess up any other headers. An empty string
860 or a forced expansion failure are noops. An added header string from a
861 transport may not end with a newline; add one if it does not. */
863 if (add_headers != NULL)
865 uschar *s = expand_string(add_headers);
868 if (!expand_string_forcedfail)
870 errno = ERRNO_CHHEADER_FAIL;
876 int len = Ustrlen(s);
879 if (!write_chunk(fd, s, len, use_crlf)) return FALSE;
880 if (s[len-1] != '\n' && !write_chunk(fd, US"\n", 1, use_crlf))
884 debug_printf("added header line(s):\n%s", s);
885 if (s[len-1] != '\n') debug_printf("\n");
886 debug_printf("---\n");
892 /* Separate headers from body with a blank line */
894 if (!write_chunk(fd, US"\n", 1, use_crlf)) return FALSE;
897 /* If the body is required, ensure that the data for check strings (formerly
898 the "from hack") is enabled by negating the length if necessary. (It will be
899 negative in cases where it isn't to apply to the headers). Then ensure the body
900 is positioned at the start of its file (following the message id), then write
901 it, applying the size limit if required. */
903 if ((options & topt_no_body) == 0)
905 nl_check_length = abs(nl_check_length);
906 nl_partial_match = 0;
907 lseek(deliver_datafile, SPOOL_DATA_START_OFFSET, SEEK_SET);
908 while ((len = read(deliver_datafile, deliver_in_buffer,
909 DELIVER_IN_BUFFER_SIZE)) > 0)
911 if (!write_chunk(fd, deliver_in_buffer, len, use_crlf)) return FALSE;
915 if (written > size_limit)
917 len = 0; /* Pretend EOF */
923 /* Finished with the check string */
925 nl_check_length = nl_escape_length = 0;
927 /* A read error on the body will have left len == -1 and errno set. */
929 if (len != 0) return FALSE;
931 /* If requested, add a terminating "." line (SMTP output). */
933 if ((options & topt_end_dot) != 0 && !write_chunk(fd, US".\n", 2, use_crlf))
937 /* Write out any remaining data in the buffer before returning. */
939 return (len = chunk_ptr - deliver_out_buffer) <= 0 ||
940 transport_write_block(fd, deliver_out_buffer, len);
944 #ifdef EXPERIMENTAL_DOMAINKEYS
946 /**********************************************************************************
947 * External interface to write the message, while signing it with domainkeys *
948 **********************************************************************************/
950 /* This function is a wrapper around transport_write_message(). It is only called
951 from the smtp transport if
952 (1) Domainkeys support is compiled in.
953 (2) The dk_private_key option on the smtp transport is set.
954 The function sets up a replacement fd into a -K file, then calls the normal
955 function. This way, the exact bits that exim would have put "on the wire" will
956 end up in the file (except for TLS encapsulation, which is the very
957 very last thing). When we are done signing the file, send the
958 signed message down the original fd (or TLS fd).
960 Arguments: as for internal_transport_write_message() above, with additional
962 uschar *dk_private_key The private key to use (filename or plain data)
963 uschar *dk_domain Override domain (normally NULL)
964 uschar *dk_selector The selector to use.
965 uschar *dk_canon The canonalization scheme to use, "simple" or "nofws"
966 uschar *dk_headers Colon-separated header list to include in the signing
968 uschar *dk_strict What to do if signing fails: 1/true => throw error
969 0/false => send anyway
971 Returns: TRUE on success; FALSE (with errno) for any failure
975 dk_transport_write_message(address_item *addr, int fd, int options,
976 int size_limit, uschar *add_headers, uschar *remove_headers,
977 uschar *check_string, uschar *escape_string, rewrite_rule *rewrite_rules,
978 int rewrite_existflags, uschar *dk_private_key, uschar *dk_domain,
979 uschar *dk_selector, uschar *dk_canon, uschar *dk_headers, uschar *dk_strict)
984 uschar dk_spool_name[256];
988 uschar *dk_signature = NULL;
991 (void)string_format(dk_spool_name, 256, "%s/input/%s/%s-%d-K",
992 spool_directory, message_subdir, message_id, (int)getpid());
993 dk_fd = Uopen(dk_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE);
996 /* Can't create spool file. Ugh. */
1002 /* Call original function */
1003 rc = transport_write_message(addr, dk_fd, options,
1004 size_limit, add_headers, remove_headers,
1005 check_string, escape_string, rewrite_rules,
1006 rewrite_existflags);
1008 /* Save error state. We must clean up before returning. */
1015 /* Rewind file and feed it to the goats^W DK lib */
1016 lseek(dk_fd, 0, SEEK_SET);
1017 dk_signature = dk_exim_sign(dk_fd,
1023 if (dk_signature != NULL)
1025 /* Send the signature first */
1026 int siglen = Ustrlen(dk_signature);
1030 if (tls_active == fd) wwritten = tls_write(dk_signature, siglen); else
1032 wwritten = write(fd,dk_signature,siglen);
1035 /* error, bail out */
1041 dk_signature += wwritten;
1044 else if (dk_strict != NULL)
1046 uschar *dk_strict_result = expand_string(dk_strict);
1047 if (dk_strict_result != NULL)
1049 if ( (strcmpic(dk_strict,US"1") == 0) ||
1050 (strcmpic(dk_strict,US"true") == 0) )
1059 /* Fetch file positition (the size) */
1060 size = lseek(dk_fd,0,SEEK_CUR);
1063 lseek(dk_fd, 0, SEEK_SET);
1065 #ifdef HAVE_LINUX_SENDFILE
1066 /* We can use sendfile() to shove the file contents
1067 to the socket. However only if we don't use TLS,
1068 in which case theres another layer of indirection
1069 before the data finally hits the socket. */
1070 if (tls_active != fd)
1074 while((copied >= 0) && (offset<size))
1076 copied = sendfile(fd, dk_fd, &offset, (size - offset));
1087 /* Send file down the original fd */
1088 while((sread = read(dk_fd,sbuf,2048)) > 0)
1091 /* write the chunk */
1094 if (tls_active == fd) wwritten = tls_write(US p, sread); else
1096 wwritten = write(fd,p,sread);
1099 /* error, bail out */
1104 if (wwritten < sread)
1106 /* short write, try again */
1121 /* unlink -K file */
1123 Uunlink(dk_spool_name);
1131 #ifdef EXPERIMENTAL_DKIM
1133 /**********************************************************************************
1134 * External interface to write the message, while signing it with DKIM *
1135 **********************************************************************************/
1137 /* This function is a wrapper around transport_write_message(). It is only called
1138 from the smtp transport if
1139 (1) DKIM support is compiled in.
1140 (2) The dkim_private_key and dkim_domain option on the smtp transport is set.
1141 The function sets up a replacement fd into a -K file, then calls the normal
1142 function. This way, the exact bits that exim would have put "on the wire" will
1143 end up in the file (except for TLS encapsulation, which is the very
1144 very last thing). When we are done signing the file, send the
1145 signed message down the original fd (or TLS fd).
1147 Arguments: as for internal_transport_write_message() above, with additional
1149 uschar *dkim_private_key The private key to use (filename or plain data)
1150 uschar *dkim_domain The domain to use
1151 uschar *dkim_selector The selector to use.
1152 uschar *dkim_canon The canonalization scheme to use, "simple" or "relaxed"
1153 uschar *dkim_strict What to do if signing fails: 1/true => throw error
1154 0/false => send anyway
1156 Returns: TRUE on success; FALSE (with errno) for any failure
1160 dkim_transport_write_message(address_item *addr, int fd, int options,
1161 int size_limit, uschar *add_headers, uschar *remove_headers,
1162 uschar *check_string, uschar *escape_string, rewrite_rule *rewrite_rules,
1163 int rewrite_existflags, uschar *dkim_private_key, uschar *dkim_domain,
1164 uschar *dkim_selector, uschar *dkim_canon, uschar *dkim_strict, uschar *dkim_sign_headers)
1169 uschar dkim_spool_name[256];
1173 uschar *dkim_signature = NULL;
1176 (void)string_format(dkim_spool_name, 256, "%s/input/%s/%s-%d-K",
1177 spool_directory, message_subdir, message_id, (int)getpid());
1178 dkim_fd = Uopen(dkim_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE);
1181 /* Can't create spool file. Ugh. */
1187 /* Call original function */
1188 rc = transport_write_message(addr, dkim_fd, options,
1189 size_limit, add_headers, remove_headers,
1190 check_string, escape_string, rewrite_rules,
1191 rewrite_existflags);
1193 /* Save error state. We must clean up before returning. */
1200 /* Rewind file and feed it to the goats^W DKIM lib */
1201 lseek(dkim_fd, 0, SEEK_SET);
1202 dkim_signature = dkim_exim_sign(dkim_fd,
1209 if (dkim_signature != NULL)
1211 /* Send the signature first */
1212 int siglen = Ustrlen(dkim_signature);
1216 if (tls_active == fd) wwritten = tls_write(dkim_signature, siglen); else
1218 wwritten = write(fd,dkim_signature,siglen);
1221 /* error, bail out */
1227 dkim_signature += wwritten;
1230 else if (dkim_strict != NULL)
1232 uschar *dkim_strict_result = expand_string(dkim_strict);
1233 if (dkim_strict_result != NULL)
1235 if ( (strcmpic(dkim_strict,US"1") == 0) ||
1236 (strcmpic(dkim_strict,US"true") == 0) )
1245 /* Fetch file positition (the size) */
1246 size = lseek(dkim_fd,0,SEEK_CUR);
1249 lseek(dkim_fd, 0, SEEK_SET);
1251 #ifdef HAVE_LINUX_SENDFILE
1252 /* We can use sendfile() to shove the file contents
1253 to the socket. However only if we don't use TLS,
1254 in which case theres another layer of indirection
1255 before the data finally hits the socket. */
1256 if (tls_active != fd)
1260 while((copied >= 0) && (offset<size))
1262 copied = sendfile(fd, dkim_fd, &offset, (size - offset));
1273 /* Send file down the original fd */
1274 while((sread = read(dkim_fd,sbuf,2048)) > 0)
1277 /* write the chunk */
1280 if (tls_active == fd) wwritten = tls_write(US p, sread); else
1282 wwritten = write(fd,p,sread);
1285 /* error, bail out */
1290 if (wwritten < sread)
1292 /* short write, try again */
1307 /* unlink -K file */
1308 (void)close(dkim_fd);
1309 Uunlink(dkim_spool_name);
1317 /*************************************************
1318 * External interface to write the message *
1319 *************************************************/
1321 /* If there is no filtering required, call the internal function above to do
1322 the real work, passing over all the arguments from this function. Otherwise,
1323 set up a filtering process, fork another process to call the internal function
1324 to write to the filter, and in this process just suck from the filter and write
1325 down the given fd. At the end, tidy up the pipes and the processes.
1327 Arguments: as for internal_transport_write_message() above
1329 Returns: TRUE on success; FALSE (with errno) for any failure
1330 transport_count is incremented by the number of bytes written
1334 transport_write_message(address_item *addr, int fd, int options,
1335 int size_limit, uschar *add_headers, uschar *remove_headers,
1336 uschar *check_string, uschar *escape_string, rewrite_rule *rewrite_rules,
1337 int rewrite_existflags)
1340 BOOL last_filter_was_NL = TRUE;
1341 int rc, len, yield, fd_read, fd_write, save_errno;
1343 pid_t filter_pid, write_pid;
1345 transport_filter_timed_out = FALSE;
1347 /* If there is no filter command set up, call the internal function that does
1348 the actual work, passing it the incoming fd, and return its result. */
1350 if (transport_filter_argv == NULL)
1351 return internal_transport_write_message(addr, fd, options, size_limit,
1352 add_headers, remove_headers, check_string, escape_string,
1353 rewrite_rules, rewrite_existflags);
1355 /* Otherwise the message must be written to a filter process and read back
1356 before being written to the incoming fd. First set up the special processing to
1357 be done during the copying. */
1359 use_crlf = (options & topt_use_crlf) != 0;
1360 nl_partial_match = -1;
1362 if (check_string != NULL && escape_string != NULL)
1364 nl_check = check_string;
1365 nl_check_length = Ustrlen(nl_check);
1366 nl_escape = escape_string;
1367 nl_escape_length = Ustrlen(nl_escape);
1369 else nl_check_length = nl_escape_length = 0;
1371 /* Start up a subprocess to run the command. Ensure that our main fd will
1372 be closed when the subprocess execs, but remove the flag afterwards.
1373 (Otherwise, if this is a TCP/IP socket, it can't get passed on to another
1374 process to deliver another message.) We get back stdin/stdout file descriptors.
1375 If the process creation failed, give an error return. */
1381 write_pid = (pid_t)(-1);
1383 (void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
1384 filter_pid = child_open(transport_filter_argv, NULL, 077, &fd_write, &fd_read,
1386 (void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) & ~FD_CLOEXEC);
1387 if (filter_pid < 0) goto TIDY_UP; /* errno set */
1390 debug_printf("process %d running as transport filter: write=%d read=%d\n",
1391 (int)filter_pid, fd_write, fd_read);
1393 /* Fork subprocess to write the message to the filter, and return the result
1394 via a(nother) pipe. While writing to the filter, we do not do the CRLF,
1395 smtp dots, or check string processing. */
1397 if (pipe(pfd) != 0) goto TIDY_UP; /* errno set */
1398 if ((write_pid = fork()) == 0)
1401 (void)close(fd_read);
1402 (void)close(pfd[pipe_read]);
1403 nl_check_length = nl_escape_length = 0;
1404 rc = internal_transport_write_message(addr, fd_write,
1405 (options & ~(topt_use_crlf | topt_end_dot)),
1406 size_limit, add_headers, remove_headers, NULL, NULL,
1407 rewrite_rules, rewrite_existflags);
1409 (void)write(pfd[pipe_write], (void *)&rc, sizeof(BOOL));
1410 (void)write(pfd[pipe_write], (void *)&save_errno, sizeof(int));
1411 (void)write(pfd[pipe_write], (void *)&(addr->more_errno), sizeof(int));
1416 /* Parent process: close our copy of the writing subprocess' pipes. */
1418 (void)close(pfd[pipe_write]);
1419 (void)close(fd_write);
1422 /* Writing process creation failed */
1426 errno = save_errno; /* restore */
1430 /* When testing, let the subprocess get going */
1432 if (running_in_test_harness) millisleep(250);
1435 debug_printf("process %d writing to transport filter\n", (int)write_pid);
1437 /* Copy the message from the filter to the output fd. A read error leaves len
1438 == -1 and errno set. We need to apply a timeout to the read, to cope with
1439 the case when the filter gets stuck, but it can be quite a long one. The
1440 default is 5m, but this is now configurable. */
1442 DEBUG(D_transport) debug_printf("copying from the filter\n");
1444 /* Copy the output of the filter, remembering if the last character was NL. If
1445 no data is returned, that counts as "ended with NL" (default setting of the
1446 variable is TRUE). */
1448 chunk_ptr = deliver_out_buffer;
1452 sigalrm_seen = FALSE;
1453 alarm(transport_filter_timeout);
1454 len = read(fd_read, deliver_in_buffer, DELIVER_IN_BUFFER_SIZE);
1459 transport_filter_timed_out = TRUE;
1463 /* If the read was successful, write the block down the original fd,
1464 remembering whether it ends in \n or not. */
1468 if (!write_chunk(fd, deliver_in_buffer, len, use_crlf)) goto TIDY_UP;
1469 last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
1472 /* Otherwise, break the loop. If we have hit EOF, set yield = TRUE. */
1476 if (len == 0) yield = TRUE;
1481 /* Tidying up code. If yield = FALSE there has been an error and errno is set
1482 to something. Ensure the pipes are all closed and the processes are removed. If
1483 there has been an error, kill the processes before waiting for them, just to be
1484 sure. Also apply a paranoia timeout. */
1489 (void)close(fd_read);
1490 if (fd_write > 0) (void)close(fd_write);
1494 if (filter_pid > 0) kill(filter_pid, SIGKILL);
1495 if (write_pid > 0) kill(write_pid, SIGKILL);
1498 /* Wait for the filter process to complete. */
1500 DEBUG(D_transport) debug_printf("waiting for filter process\n");
1501 if (filter_pid > 0 && (rc = child_close(filter_pid, 30)) != 0 && yield)
1504 save_errno = ERRNO_FILTER_FAIL;
1505 addr->more_errno = rc;
1506 DEBUG(D_transport) debug_printf("filter process returned %d\n", rc);
1509 /* Wait for the writing process to complete. If it ends successfully,
1510 read the results from its pipe, provided we haven't already had a filter
1513 DEBUG(D_transport) debug_printf("waiting for writing process\n");
1516 rc = child_close(write_pid, 30);
1522 (void)read(pfd[pipe_read], (void *)&ok, sizeof(BOOL));
1525 (void)read(pfd[pipe_read], (void *)&save_errno, sizeof(int));
1526 (void)read(pfd[pipe_read], (void *)&(addr->more_errno), sizeof(int));
1533 save_errno = ERRNO_FILTER_FAIL;
1534 addr->more_errno = rc;
1535 DEBUG(D_transport) debug_printf("writing process returned %d\n", rc);
1539 (void)close(pfd[pipe_read]);
1541 /* If there have been no problems we can now add the terminating "." if this is
1542 SMTP output, turning off escaping beforehand. If the last character from the
1543 filter was not NL, insert a NL to make the SMTP protocol work. */
1547 nl_check_length = nl_escape_length = 0;
1548 if ((options & topt_end_dot) != 0 && (last_filter_was_NL?
1549 !write_chunk(fd, US".\n", 2, use_crlf) :
1550 !write_chunk(fd, US"\n.\n", 3, use_crlf)))
1555 /* Write out any remaining data in the buffer. */
1559 yield = (len = chunk_ptr - deliver_out_buffer) <= 0 ||
1560 transport_write_block(fd, deliver_out_buffer, len);
1563 else errno = save_errno; /* From some earlier error */
1567 debug_printf("end of filtering transport writing: yield=%d\n", yield);
1569 debug_printf("errno=%d more_errno=%d\n", errno, addr->more_errno);
1579 /*************************************************
1580 * Update waiting database *
1581 *************************************************/
1583 /* This is called when an address is deferred by remote transports that are
1584 capable of sending more than one message over one connection. A database is
1585 maintained for each transport, keeping track of which messages are waiting for
1586 which hosts. The transport can then consult this when eventually a successful
1587 delivery happens, and if it finds that another message is waiting for the same
1588 host, it can fire up a new process to deal with it using the same connection.
1590 The database records are keyed by host name. They can get full if there are
1591 lots of messages waiting, and so there is a continuation mechanism for them.
1593 Each record contains a list of message ids, packed end to end without any
1594 zeros. Each one is MESSAGE_ID_LENGTH bytes long. The count field says how many
1595 in this record, and the sequence field says if there are any other records for
1596 this host. If the sequence field is 0, there are none. If it is 1, then another
1597 record with the name <hostname>:0 exists; if it is 2, then two other records
1598 with sequence numbers 0 and 1 exist, and so on.
1600 Currently, an exhaustive search of all continuation records has to be done to
1601 determine whether to add a message id to a given record. This shouldn't be
1602 too bad except in extreme cases. I can't figure out a *simple* way of doing
1605 Old records should eventually get swept up by the exim_tidydb utility.
1608 hostlist list of hosts that this message could be sent to
1609 tpname name of the transport
1615 transport_update_waiting(host_item *hostlist, uschar *tpname)
1618 uschar *prevname = US"";
1623 DEBUG(D_transport) debug_printf("updating wait-%s database\n", tpname);
1625 /* Open the database for this transport */
1627 sprintf(CS buffer, "wait-%.200s", tpname);
1628 dbm_file = dbfn_open(buffer, O_RDWR, &dbblock, TRUE);
1629 if (dbm_file == NULL) return;
1631 /* Scan the list of hosts for which this message is waiting, and ensure
1632 that the message id is in each host record. */
1634 for (host = hostlist; host!= NULL; host = host->next)
1636 BOOL already = FALSE;
1637 dbdata_wait *host_record;
1641 /* Skip if this is the same host as we just processed; otherwise remember
1642 the name for next time. */
1644 if (Ustrcmp(prevname, host->name) == 0) continue;
1645 prevname = host->name;
1647 /* Look up the host record; if there isn't one, make an empty one. */
1649 host_record = dbfn_read(dbm_file, host->name);
1650 if (host_record == NULL)
1652 host_record = store_get(sizeof(dbdata_wait) + MESSAGE_ID_LENGTH);
1653 host_record->count = host_record->sequence = 0;
1656 /* Compute the current length */
1658 host_length = host_record->count * MESSAGE_ID_LENGTH;
1660 /* Search the record to see if the current message is already in it. */
1662 for (s = host_record->text; s < host_record->text + host_length;
1663 s += MESSAGE_ID_LENGTH)
1665 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1666 { already = TRUE; break; }
1669 /* If we haven't found this message in the main record, search any
1670 continuation records that exist. */
1672 for (i = host_record->sequence - 1; i >= 0 && !already; i--)
1675 sprintf(CS buffer, "%.200s:%d", host->name, i);
1676 cont = dbfn_read(dbm_file, buffer);
1679 int clen = cont->count * MESSAGE_ID_LENGTH;
1680 for (s = cont->text; s < cont->text + clen; s += MESSAGE_ID_LENGTH)
1682 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1683 { already = TRUE; break; }
1688 /* If this message is already in a record, no need to update. */
1692 DEBUG(D_transport) debug_printf("already listed for %s\n", host->name);
1697 /* If this record is full, write it out with a new name constructed
1698 from the sequence number, increase the sequence number, and empty
1701 if (host_record->count >= WAIT_NAME_MAX)
1703 sprintf(CS buffer, "%.200s:%d", host->name, host_record->sequence);
1704 dbfn_write(dbm_file, buffer, host_record, sizeof(dbdata_wait) + host_length);
1705 host_record->sequence++;
1706 host_record->count = 0;
1710 /* If this record is not full, increase the size of the record to
1711 allow for one new message id. */
1716 store_get(sizeof(dbdata_wait) + host_length + MESSAGE_ID_LENGTH);
1717 memcpy(newr, host_record, sizeof(dbdata_wait) + host_length);
1721 /* Now add the new name on the end */
1723 memcpy(host_record->text + host_length, message_id, MESSAGE_ID_LENGTH);
1724 host_record->count++;
1725 host_length += MESSAGE_ID_LENGTH;
1727 /* Update the database */
1729 dbfn_write(dbm_file, host->name, host_record, sizeof(dbdata_wait) + host_length);
1730 DEBUG(D_transport) debug_printf("added to list for %s\n", host->name);
1735 dbfn_close(dbm_file);
1741 /*************************************************
1742 * Test for waiting messages *
1743 *************************************************/
1745 /* This function is called by a remote transport which uses the previous
1746 function to remember which messages are waiting for which remote hosts. It's
1747 called after a successful delivery and its job is to check whether there is
1748 another message waiting for the same host. However, it doesn't do this if the
1749 current continue sequence is greater than the maximum supplied as an argument,
1750 or greater than the global connection_max_messages, which, if set, overrides.
1753 transport_name name of the transport
1754 hostname name of the host
1755 local_message_max maximum number of messages down one connection
1756 as set by the caller transport
1757 new_message_id set to the message id of a waiting message
1758 more set TRUE if there are yet more messages waiting
1760 Returns: TRUE if new_message_id set; FALSE otherwise
1764 transport_check_waiting(uschar *transport_name, uschar *hostname,
1765 int local_message_max, uschar *new_message_id, BOOL *more)
1767 dbdata_wait *host_record;
1768 int host_length, path_len;
1777 debug_printf("transport_check_waiting entered\n");
1778 debug_printf(" sequence=%d local_max=%d global_max=%d\n",
1779 continue_sequence, local_message_max, connection_max_messages);
1782 /* Do nothing if we have hit the maximum number that can be send down one
1785 if (connection_max_messages >= 0) local_message_max = connection_max_messages;
1786 if (local_message_max > 0 && continue_sequence >= local_message_max)
1789 debug_printf("max messages for one connection reached: returning\n");
1793 /* Open the waiting information database. */
1795 sprintf(CS buffer, "wait-%.200s", transport_name);
1796 dbm_file = dbfn_open(buffer, O_RDWR, &dbblock, TRUE);
1797 if (dbm_file == NULL) return FALSE;
1799 /* See if there is a record for this host; if not, there's nothing to do. */
1801 host_record = dbfn_read(dbm_file, hostname);
1802 if (host_record == NULL)
1804 dbfn_close(dbm_file);
1805 DEBUG(D_transport) debug_printf("no messages waiting for %s\n", hostname);
1809 /* If the data in the record looks corrupt, just log something and
1810 don't try to use it. */
1812 if (host_record->count > WAIT_NAME_MAX)
1814 dbfn_close(dbm_file);
1815 log_write(0, LOG_MAIN|LOG_PANIC, "smtp-wait database entry for %s has bad "
1816 "count=%d (max=%d)", hostname, host_record->count, WAIT_NAME_MAX);
1820 /* Scan the message ids in the record from the end towards the beginning,
1821 until one is found for which a spool file actually exists. If the record gets
1822 emptied, delete it and continue with any continuation records that may exist.
1825 host_length = host_record->count * MESSAGE_ID_LENGTH;
1827 /* Loop to handle continuation host records in the database */
1833 sprintf(CS buffer, "%s/input/", spool_directory);
1834 path_len = Ustrlen(buffer);
1836 for (host_length -= MESSAGE_ID_LENGTH; host_length >= 0;
1837 host_length -= MESSAGE_ID_LENGTH)
1839 struct stat statbuf;
1840 Ustrncpy(new_message_id, host_record->text + host_length,
1842 new_message_id[MESSAGE_ID_LENGTH] = 0;
1844 if (split_spool_directory)
1845 sprintf(CS(buffer + path_len), "%c/%s-D", new_message_id[5], new_message_id);
1847 sprintf(CS(buffer + path_len), "%s-D", new_message_id);
1849 /* The listed message may be the one we are currently processing. If
1850 so, we want to remove it from the list without doing anything else.
1851 If not, do a stat to see if it is an existing message. If it is, break
1852 the loop to handle it. No need to bother about locks; as this is all
1853 "hint" processing, it won't matter if it doesn't exist by the time exim
1854 actually tries to deliver it. */
1856 if (Ustrcmp(new_message_id, message_id) != 0 &&
1857 Ustat(buffer, &statbuf) == 0)
1864 /* If we have removed all the message ids from the record delete the record.
1865 If there is a continuation record, fetch it and remove it from the file,
1866 as it will be rewritten as the main record. Repeat in the case of an
1867 empty continuation. */
1869 while (host_length <= 0)
1872 dbdata_wait *newr = NULL;
1874 /* Search for a continuation */
1876 for (i = host_record->sequence - 1; i >= 0 && newr == NULL; i--)
1878 sprintf(CS buffer, "%.200s:%d", hostname, i);
1879 newr = dbfn_read(dbm_file, buffer);
1882 /* If no continuation, delete the current and break the loop */
1886 dbfn_delete(dbm_file, hostname);
1890 /* Else replace the current with the continuation */
1892 dbfn_delete(dbm_file, buffer);
1894 host_length = host_record->count * MESSAGE_ID_LENGTH;
1897 /* If we found an existing message, break the continuation loop. */
1901 /* If host_length <= 0 we have emptied a record and not found a good message,
1902 and there are no continuation records. Otherwise there is a continuation
1903 record to process. */
1905 if (host_length <= 0)
1907 dbfn_close(dbm_file);
1908 DEBUG(D_transport) debug_printf("waiting messages already delivered\n");
1913 /* Control gets here when an existing message has been encountered; its
1914 id is in new_message_id, and host_length is the revised length of the
1915 host record. If it is zero, the record has been removed. Update the
1916 record if required, close the database, and return TRUE. */
1918 if (host_length > 0)
1920 host_record->count = host_length/MESSAGE_ID_LENGTH;
1921 dbfn_write(dbm_file, hostname, host_record, (int)sizeof(dbdata_wait) + host_length);
1925 dbfn_close(dbm_file);
1931 /*************************************************
1932 * Deliver waiting message down same socket *
1933 *************************************************/
1935 /* Fork a new exim process to deliver the message, and do a re-exec, both to
1936 get a clean delivery process, and to regain root privilege in cases where it
1937 has been given away.
1940 transport_name to pass to the new process
1943 id the new message to process
1944 socket_fd the connected socket
1946 Returns: FALSE if fork fails; TRUE otherwise
1950 transport_pass_socket(uschar *transport_name, uschar *hostname,
1951 uschar *hostaddress, uschar *id, int socket_fd)
1956 DEBUG(D_transport) debug_printf("transport_pass_socket entered\n");
1958 if ((pid = fork()) == 0)
1963 /* Disconnect entirely from the parent process. If we are running in the
1964 test harness, wait for a bit to allow the previous process time to finish,
1965 write the log, etc., so that the output is always in the same order for
1966 automatic comparison. */
1968 if ((pid = fork()) != 0) _exit(EXIT_SUCCESS);
1969 if (running_in_test_harness) sleep(1);
1971 /* Set up the calling arguments; use the standard function for the basics,
1972 but we have a number of extras that may be added. */
1974 argv = child_exec_exim(CEE_RETURN_ARGV, TRUE, &i, FALSE, 0);
1976 if (smtp_authenticated) argv[i++] = US"-MCA";
1979 if (tls_offered) argv[i++] = US"-MCT";
1982 if (smtp_use_size) argv[i++] = US"-MCS";
1983 if (smtp_use_pipelining) argv[i++] = US"-MCP";
1985 if (queue_run_pid != (pid_t)0)
1987 argv[i++] = US"-MCQ";
1988 argv[i++] = string_sprintf("%d", queue_run_pid);
1989 argv[i++] = string_sprintf("%d", queue_run_pipe);
1992 argv[i++] = US"-MC";
1993 argv[i++] = transport_name;
1994 argv[i++] = hostname;
1995 argv[i++] = hostaddress;
1996 argv[i++] = string_sprintf("%d", continue_sequence + 1);
2000 /* Arrange for the channel to be on stdin. */
2004 (void)dup2(socket_fd, 0);
2005 (void)close(socket_fd);
2008 DEBUG(D_exec) debug_print_argv(argv);
2009 exim_nullstd(); /* Ensure std{out,err} exist */
2010 execv(CS argv[0], (char *const *)argv);
2012 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
2013 _exit(errno); /* Note: must be _exit(), NOT exit() */
2016 /* If the process creation succeeded, wait for the first-level child, which
2017 immediately exits, leaving the second level process entirely disconnected from
2023 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
2024 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded\n");
2029 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
2037 /*************************************************
2038 * Set up direct (non-shell) command *
2039 *************************************************/
2041 /* This function is called when a command line is to be parsed and executed
2042 directly, without the use of /bin/sh. It is called by the pipe transport,
2043 the queryprogram router, and also from the main delivery code when setting up a
2044 transport filter process. The code for ETRN also makes use of this; in that
2045 case, no addresses are passed.
2048 argvptr pointer to anchor for argv vector
2049 cmd points to the command string
2050 expand_arguments true if expansion is to occur
2051 expand_failed error value to set if expansion fails; not relevant if
2053 addr chain of addresses, or NULL
2054 etext text for use in error messages
2055 errptr where to put error message if addr is NULL;
2056 otherwise it is put in the first address
2058 Returns: TRUE if all went well; otherwise an error will be
2059 set in the first address and FALSE returned
2063 transport_set_up_command(uschar ***argvptr, uschar *cmd, BOOL expand_arguments,
2064 int expand_failed, address_item *addr, uschar *etext, uschar **errptr)
2069 int address_count = 0;
2073 /* Get store in which to build an argument list. Count the number of addresses
2074 supplied, and allow for that many arguments, plus an additional 60, which
2075 should be enough for anybody. Multiple addresses happen only when the local
2076 delivery batch option is set. */
2078 for (ad = addr; ad != NULL; ad = ad->next) address_count++;
2079 max_args = address_count + 60;
2080 *argvptr = argv = store_get((max_args+1)*sizeof(uschar *));
2082 /* Split the command up into arguments terminated by white space. Lose
2083 trailing space at the start and end. Double-quoted arguments can contain \\ and
2084 \" escapes and so can be handled by the standard function; single-quoted
2085 arguments are verbatim. Copy each argument into a new string. */
2088 while (isspace(*s)) s++;
2090 while (*s != 0 && argcount < max_args)
2095 while (*ss != 0 && *ss != '\'') ss++;
2096 argv[argcount++] = ss = store_get(ss - s++);
2097 while (*s != 0 && *s != '\'') *ss++ = *s++;
2101 else argv[argcount++] = string_dequote(&s);
2102 while (isspace(*s)) s++;
2105 argv[argcount] = (uschar *)0;
2107 /* If *s != 0 we have run out of argument slots. */
2111 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
2115 addr->transport_return = FAIL;
2116 addr->message = msg;
2122 /* Expand each individual argument if required. Expansion happens for pipes set
2123 up in filter files and with directly-supplied commands. It does not happen if
2124 the pipe comes from a traditional .forward file. A failing expansion is a big
2125 disaster if the command came from Exim's configuration; if it came from a user
2126 it is just a normal failure. The expand_failed value is used as the error value
2127 to cater for these two cases.
2129 An argument consisting just of the text "$pipe_addresses" is treated specially.
2130 It is not passed to the general expansion function. Instead, it is replaced by
2131 a number of arguments, one for each address. This avoids problems with shell
2132 metacharacters and spaces in addresses.
2134 If the parent of the top address has an original part of "system-filter", this
2135 pipe was set up by the system filter, and we can permit the expansion of
2140 debug_printf("direct command:\n");
2141 for (i = 0; argv[i] != (uschar *)0; i++)
2142 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2145 if (expand_arguments)
2147 BOOL allow_dollar_recipients = addr != NULL &&
2148 addr->parent != NULL &&
2149 Ustrcmp(addr->parent->address, "system-filter") == 0;
2151 for (i = 0; argv[i] != (uschar *)0; i++)
2154 /* Handle special fudge for passing an address list */
2157 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
2158 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
2162 if (argcount + address_count - 1 > max_args)
2164 addr->transport_return = FAIL;
2165 addr->message = string_sprintf("Too many arguments to command \"%s\" "
2166 "in %s", cmd, etext);
2170 additional = address_count - 1;
2172 memmove(argv + i + 1 + additional, argv + i + 1,
2173 (argcount - i)*sizeof(uschar *));
2175 for (ad = addr; ad != NULL; ad = ad->next) argv[i++] = ad->address;
2179 /* Handle normal expansion string */
2183 uschar *expanded_arg;
2184 enable_dollar_recipients = allow_dollar_recipients;
2185 expanded_arg = expand_string(argv[i]);
2186 enable_dollar_recipients = FALSE;
2188 if (expanded_arg == NULL)
2190 uschar *msg = string_sprintf("Expansion of \"%s\" "
2191 "from command \"%s\" in %s failed: %s",
2192 argv[i], cmd, etext, expand_string_message);
2195 addr->transport_return = expand_failed;
2196 addr->message = msg;
2201 argv[i] = expanded_arg;
2207 debug_printf("direct command after expansion:\n");
2208 for (i = 0; argv[i] != (uschar *)0; i++)
2209 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2216 /* End of transport.c */