1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* General functions concerned with transportation, and generic options for all
14 /* Generic options for transports, all of which live inside transport_instance
15 data blocks and which therefore have the opt_public flag set. Note that there
16 are other options living inside this structure which can be set only from
17 certain transports. */
18 #define LOFF(field) OPT_OFF(transport_instance, field)
20 optionlist optionlist_transports[] = {
22 { "*expand_group", opt_stringptr|opt_hidden|opt_public,
24 { "*expand_user", opt_stringptr|opt_hidden|opt_public,
26 { "*headers_rewrite_flags", opt_int|opt_public|opt_hidden,
27 LOFF(rewrite_existflags) },
28 { "*headers_rewrite_rules", opt_void|opt_public|opt_hidden,
29 LOFF(rewrite_rules) },
30 { "*set_group", opt_bool|opt_hidden|opt_public,
32 { "*set_user", opt_bool|opt_hidden|opt_public,
34 { "body_only", opt_bool|opt_public,
36 { "current_directory", opt_stringptr|opt_public,
38 { "debug_print", opt_stringptr | opt_public,
40 { "delivery_date_add", opt_bool|opt_public,
41 LOFF(delivery_date_add) },
42 { "disable_logging", opt_bool|opt_public,
43 LOFF(disable_logging) },
44 { "driver", opt_stringptr|opt_public,
46 { "envelope_to_add", opt_bool|opt_public,
47 LOFF(envelope_to_add) },
49 { "event_action", opt_stringptr | opt_public,
52 { "group", opt_expand_gid|opt_public,
54 { "headers_add", opt_stringptr|opt_public|opt_rep_str,
56 { "headers_only", opt_bool|opt_public,
58 { "headers_remove", opt_stringptr|opt_public|opt_rep_str,
59 LOFF(remove_headers) },
60 { "headers_rewrite", opt_rewrite|opt_public,
61 LOFF(headers_rewrite) },
62 { "home_directory", opt_stringptr|opt_public,
64 { "initgroups", opt_bool|opt_public,
66 { "max_parallel", opt_stringptr|opt_public,
68 { "message_size_limit", opt_stringptr|opt_public,
69 LOFF(message_size_limit) },
70 { "rcpt_include_affixes", opt_bool|opt_public,
71 LOFF(rcpt_include_affixes) },
72 { "retry_use_local_part", opt_bool|opt_public,
73 LOFF(retry_use_local_part) },
74 { "return_path", opt_stringptr|opt_public,
76 { "return_path_add", opt_bool|opt_public,
77 LOFF(return_path_add) },
78 { "shadow_condition", opt_stringptr|opt_public,
79 LOFF(shadow_condition) },
80 { "shadow_transport", opt_stringptr|opt_public,
82 { "transport_filter", opt_stringptr|opt_public,
83 LOFF(filter_command) },
84 { "transport_filter_timeout", opt_time|opt_public,
85 LOFF(filter_timeout) },
86 { "user", opt_expand_uid|opt_public,
90 int optionlist_transports_size = nelem(optionlist_transports);
94 # include "macro_predef.h"
97 options_transports(void)
101 options_from_list(optionlist_transports, nelem(optionlist_transports), US"TRANSPORTS", NULL);
103 for (transport_info * ti = transports_available; ti->driver_name[0]; ti++)
105 spf(buf, sizeof(buf), US"_DRIVER_TRANSPORT_%T", ti->driver_name);
106 builtin_macro_create(buf);
107 options_from_list(ti->options, (unsigned)*ti->options_count, US"TRANSPORT", ti->driver_name);
111 #else /*!MACRO_PREDEF*/
113 /* Structure for keeping list of addresses that have been added to
114 Envelope-To:, in order to avoid duplication. */
122 /* Static data for write_chunk() */
124 static uschar *chunk_ptr; /* chunk pointer */
125 static uschar *nl_check; /* string to look for at line start */
126 static int nl_check_length; /* length of same */
127 static uschar *nl_escape; /* string to insert */
128 static int nl_escape_length; /* length of same */
129 static int nl_partial_match; /* length matched at chunk end */
132 /*************************************************
133 * Initialize transport list *
134 *************************************************/
136 /* Read the transports section of the configuration file, and set up a chain of
137 transport instances according to its contents. Each transport has generic
138 options and may also have its own private options. This function is only ever
139 called when transports == NULL. We use generic code in readconf to do most of
145 readconf_driver_init(US"transport",
146 (driver_instance **)(&transports), /* chain anchor */
147 (driver_info *)transports_available, /* available drivers */
148 sizeof(transport_info), /* size of info block */
149 &transport_defaults, /* default values for generic options */
150 sizeof(transport_instance), /* size of instance block */
151 optionlist_transports, /* generic options */
152 optionlist_transports_size);
154 /* Now scan the configured transports and check inconsistencies. A shadow
155 transport is permitted only for local transports. */
157 for (transport_instance * t = transports; t; t = t->next)
159 if (!t->info->local && t->shadow)
160 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
161 "shadow transport not allowed on non-local transport %s", t->name);
163 if (t->body_only && t->headers_only)
164 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
165 "%s transport: body_only and headers_only are mutually exclusive",
172 /*************************************************
173 * Write block of data *
174 *************************************************/
177 tpt_write(int fd, uschar * block, int len, BOOL more, int options)
181 tls_out.active.sock == fd
182 ? tls_write(tls_out.active.tls_ctx, block, len, more) :
185 more && !(options & topt_not_socket) ? send(fd, block, len, MSG_MORE) :
187 write(fd, block, len);
190 /* Subroutine called by write_chunk() and at the end of the message actually
191 to write a data block. Also called directly by some transports to write
192 additional data to the file descriptor (e.g. prefix, suffix).
194 If a transport wants data transfers to be timed, it sets a non-zero value in
195 transport_write_timeout. A non-zero transport_write_timeout causes a timer to
196 be set for each block of data written from here. If time runs out, then write()
197 fails and provokes an error return. The caller can then inspect sigalrm_seen to
200 On some systems, if a quota is exceeded during the write, the yield is the
201 number of bytes written rather than an immediate error code. This also happens
202 on some systems in other cases, for example a pipe that goes away because the
203 other end's process terminates (Linux). On other systems, (e.g. Solaris 2) you
204 get the error codes the first time.
206 The write() function is also interruptible; the Solaris 2.6 man page says:
208 If write() is interrupted by a signal before it writes any
209 data, it will return -1 with errno set to EINTR.
211 If write() is interrupted by a signal after it successfully
212 writes some data, it will return the number of bytes written.
214 To handle these cases, we want to restart the write() to output the remainder
215 of the data after a non-negative return from write(), except after a timeout.
216 In the error cases (EDQUOT, EPIPE) no bytes get written the second time, and a
217 proper error then occurs. In principle, after an interruption, the second
218 write() could suffer the same fate, but we do not want to continue for
219 evermore, so stick a maximum repetition count on the loop to act as a
223 tctx transport context: file descriptor or string to write to
224 block block of bytes to write
225 len number of bytes to write
226 more further data expected soon
228 Returns: TRUE on success, FALSE on failure (with errno preserved);
229 transport_count is incremented by the number of bytes written
233 transport_write_block_fd(transport_ctx * tctx, uschar * block, int len, BOOL more)
236 int local_timeout = transport_write_timeout;
240 /* This loop is for handling incomplete writes and other retries. In most
241 normal cases, it is only ever executed once. */
243 for (int i = 0; i < 100; i++)
246 debug_printf("writing data block fd=%d size=%d timeout=%d%s\n",
247 fd, len, local_timeout, more ? " (more expected)" : "");
249 /* When doing TCP Fast Open we may get this far before the 3-way handshake
250 is complete, and write returns ENOTCONN. Detect that, wait for the socket
251 to become writable, and retry once only. */
256 /* This code makes use of alarm() in order to implement the timeout. This
257 isn't a very tidy way of doing things. Using non-blocking I/O with select()
258 provides a neater approach. However, I don't know how to do this when TLS is
261 if (transport_write_timeout <= 0) /* No timeout wanted */
263 rc = tpt_write(fd, block, len, more, tctx->options);
266 else /* Timeout wanted. */
268 ALARM(local_timeout);
269 rc = tpt_write(fd, block, len, more, tctx->options);
271 local_timeout = ALARM_CLR(0);
279 if (rc >= 0 || errno != ENOTCONN || connretry <= 0)
282 FD_ZERO(&fds); FD_SET(fd, &fds);
283 select(fd+1, NULL, &fds, NULL, NULL); /* could set timout? */
287 /* Hopefully, the most common case is success, so test that first. */
289 if (rc == len) { transport_count += len; return TRUE; }
291 /* A non-negative return code is an incomplete write. Try again for the rest
292 of the block. If we have exactly hit the timeout, give up. */
298 transport_count += rc;
299 DEBUG(D_transport) debug_printf("write incomplete (%d)\n", rc);
300 goto CHECK_TIMEOUT; /* A few lines below */
303 /* A negative return code with an EINTR error is another form of
304 incomplete write, zero bytes having been written */
306 if (save_errno == EINTR)
309 debug_printf("write interrupted before anything written\n");
310 goto CHECK_TIMEOUT; /* A few lines below */
313 /* A response of EAGAIN from write() is likely only in the case of writing
314 to a FIFO that is not swallowing the data as fast as Exim is writing it. */
316 if (save_errno == EAGAIN)
319 debug_printf("write temporarily locked out, waiting 1 sec\n");
322 /* Before continuing to try another write, check that we haven't run out of
326 if (transport_write_timeout > 0 && local_timeout <= 0)
334 /* Otherwise there's been an error */
336 DEBUG(D_transport) debug_printf("writing error %d: %s\n", save_errno,
337 strerror(save_errno));
342 /* We've tried and tried and tried but still failed */
344 errno = ERRNO_WRITEINCOMPLETE;
350 transport_write_block(transport_ctx * tctx, uschar *block, int len, BOOL more)
352 if (!(tctx->options & topt_output_string))
353 return transport_write_block_fd(tctx, block, len, more);
355 /* Write to expanding-string. NOTE: not NUL-terminated */
358 tctx->u.msg = string_get(1024);
360 tctx->u.msg = string_catn(tctx->u.msg, block, len);
367 /*************************************************
368 * Write formatted string *
369 *************************************************/
371 /* This is called by various transports. It is a convenience function.
376 ... arguments for format
378 Returns: the yield of transport_write_block()
382 transport_write_string(int fd, const char *format, ...)
384 transport_ctx tctx = {{0}};
385 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer };
388 /* Use taint-unchecked routines for writing into big_buffer, trusting
389 that the result will never be expanded. */
391 va_start(ap, format);
392 if (!string_vformat(&gs, SVFMT_TAINT_NOCHK, format, ap))
393 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong formatted string in transport");
396 return transport_write_block(&tctx, gs.s, gs.ptr, FALSE);
403 transport_write_reset(int options)
405 if (!(options & topt_continuation)) chunk_ptr = deliver_out_buffer;
406 nl_partial_match = -1;
407 nl_check_length = nl_escape_length = 0;
412 /*************************************************
413 * Write character chunk *
414 *************************************************/
416 /* Subroutine used by transport_write_message() to scan character chunks for
417 newlines and act appropriately. The object is to minimise the number of writes.
418 The output byte stream is buffered up in deliver_out_buffer, which is written
419 only when it gets full, thus minimizing write operations and TCP packets.
421 Static data is used to handle the case when the last character of the previous
422 chunk was NL, or matched part of the data that has to be escaped.
425 tctx transport context - processing to be done during output,
426 and file descriptor to write to
427 chunk pointer to data to write
428 len length of data to write
430 In addition, the static nl_xxx variables must be set as required.
432 Returns: TRUE on success, FALSE on failure (with errno preserved)
436 write_chunk(transport_ctx * tctx, uschar *chunk, int len)
438 uschar *start = chunk;
439 uschar *end = chunk + len;
440 int mlen = DELIVER_OUT_BUFFER_SIZE - nl_escape_length - 2;
442 /* The assumption is made that the check string will never stretch over move
443 than one chunk since the only time there are partial matches is when copying
444 the body in large buffers. There is always enough room in the buffer for an
445 escape string, since the loop below ensures this for each character it
446 processes, and it won't have stuck in the escape string if it left a partial
449 if (nl_partial_match >= 0)
451 if (nl_check_length > 0 && len >= nl_check_length &&
452 Ustrncmp(start, nl_check + nl_partial_match,
453 nl_check_length - nl_partial_match) == 0)
455 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
456 chunk_ptr += nl_escape_length;
457 start += nl_check_length - nl_partial_match;
460 /* The partial match was a false one. Insert the characters carried over
461 from the previous chunk. */
463 else if (nl_partial_match > 0)
465 Ustrncpy(chunk_ptr, nl_check, nl_partial_match);
466 chunk_ptr += nl_partial_match;
469 nl_partial_match = -1;
472 /* Now process the characters in the chunk. Whenever we hit a newline we check
473 for possible escaping. The code for the non-NL route should be as fast as
476 for (uschar * ptr = start; ptr < end; ptr++)
480 /* Flush the buffer if it has reached the threshold - we want to leave enough
481 room for the next uschar, plus a possible extra CR for an LF, plus the escape
484 if ((len = chunk_ptr - deliver_out_buffer) > mlen)
486 DEBUG(D_transport) debug_printf("flushing headers buffer\n");
488 /* If CHUNKING, prefix with BDAT (size) NON-LAST. Also, reap responses
489 from previous SMTP commands. */
491 if (tctx->options & topt_use_bdat && tctx->chunk_cb)
493 if ( tctx->chunk_cb(tctx, (unsigned)len, 0) != OK
494 || !transport_write_block(tctx, deliver_out_buffer, len, FALSE)
495 || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
500 if (!transport_write_block(tctx, deliver_out_buffer, len, FALSE))
502 chunk_ptr = deliver_out_buffer;
505 /* Remove CR before NL if required */
507 if ( *ptr == '\r' && ptr[1] == '\n'
508 && !(tctx->options & topt_use_crlf)
509 && f.spool_file_wireformat
513 if ((ch = *ptr) == '\n')
515 int left = end - ptr - 1; /* count of chars left after NL */
517 /* Insert CR before NL if required */
519 if (tctx->options & topt_use_crlf && !f.spool_file_wireformat)
522 transport_newlines++;
524 /* The check_string test (formerly "from hack") replaces the specific
525 string at the start of a line with an escape string (e.g. "From " becomes
526 ">From " or "." becomes "..". It is a case-sensitive test. The length
527 check above ensures there is always enough room to insert this string. */
529 if (nl_check_length > 0)
531 if (left >= nl_check_length &&
532 Ustrncmp(ptr+1, nl_check, nl_check_length) == 0)
534 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
535 chunk_ptr += nl_escape_length;
536 ptr += nl_check_length;
539 /* Handle the case when there isn't enough left to match the whole
540 check string, but there may be a partial match. We remember how many
541 characters matched, and finish processing this chunk. */
543 else if (left <= 0) nl_partial_match = 0;
545 else if (Ustrncmp(ptr+1, nl_check, left) == 0)
547 nl_partial_match = left;
553 /* Not a NL character */
555 else *chunk_ptr++ = ch;
564 /*************************************************
565 * Generate address for RCPT TO *
566 *************************************************/
568 /* This function puts together an address for RCPT to, using the caseful
569 version of the local part and the caseful version of the domain. If there is no
570 prefix or suffix, or if affixes are to be retained, we can just use the
571 original address. Otherwise, if there is a prefix but no suffix we can use a
572 pointer into the original address. If there is a suffix, however, we have to
576 addr the address item
577 include_affixes TRUE if affixes are to be included
583 transport_rcpt_address(address_item *addr, BOOL include_affixes)
590 setflag(addr, af_include_affixes); /* Affects logged => line */
591 return addr->address;
594 if (addr->suffix == NULL)
596 if (addr->prefix == NULL) return addr->address;
597 return addr->address + Ustrlen(addr->prefix);
600 at = Ustrrchr(addr->address, '@');
601 plen = (addr->prefix == NULL)? 0 : Ustrlen(addr->prefix);
602 slen = Ustrlen(addr->suffix);
604 return string_sprintf("%.*s@%s", (int)(at - addr->address - plen - slen),
605 addr->address + plen, at + 1);
609 /*************************************************
610 * Output Envelope-To: address & scan duplicates *
611 *************************************************/
613 /* This function is called from internal_transport_write_message() below, when
614 generating an Envelope-To: header line. It checks for duplicates of the given
615 address and its ancestors. When one is found, this function calls itself
616 recursively, to output the envelope address of the duplicate.
618 We want to avoid duplication in the list, which can arise for example when
619 A->B,C and then both B and C alias to D. This can also happen when there are
620 unseen drivers in use. So a list of addresses that have been output is kept in
623 It is also possible to have loops in the address ancestry/duplication graph,
624 for example if there are two top level addresses A and B and we have A->B,C and
625 B->A. To break the loop, we use a list of processed addresses in the dlist
628 After handling duplication, this function outputs the progenitor of the given
632 p the address we are interested in
633 pplist address of anchor of the list of addresses not to output
634 pdlist address of anchor of the list of processed addresses
635 first TRUE if this is the first address; set it FALSE afterwards
636 tctx transport context - processing to be done during output
637 and the file descriptor to write to
639 Returns: FALSE if writing failed
643 write_env_to(address_item *p, struct aci **pplist, struct aci **pdlist,
644 BOOL *first, transport_ctx * tctx)
649 /* Do nothing if we have already handled this address. If not, remember it
650 so that we don't handle it again. */
652 for (ppp = *pdlist; ppp; ppp = ppp->next) if (p == ppp->ptr) return TRUE;
654 ppp = store_get(sizeof(struct aci), FALSE);
659 /* Now scan up the ancestry, checking for duplicates at each generation. */
661 for (pp = p;; pp = pp->parent)
664 for (dup = addr_duplicate; dup; dup = dup->next)
665 if (dup->dupof == pp) /* a dup of our address */
666 if (!write_env_to(dup, pplist, pdlist, first, tctx))
668 if (!pp->parent) break;
671 /* Check to see if we have already output the progenitor. */
673 for (ppp = *pplist; ppp; ppp = ppp->next) if (pp == ppp->ptr) break;
674 if (ppp) return TRUE;
676 /* Remember what we have output, and output it. */
678 ppp = store_get(sizeof(struct aci), FALSE);
683 if (!*first && !write_chunk(tctx, US",\n ", 3)) return FALSE;
685 return write_chunk(tctx, pp->address, Ustrlen(pp->address));
691 /* Add/remove/rewrite headers, and send them plus the empty-line separator.
697 addr (chain of) addresses (for extra headers), or NULL;
698 only the first address is used
699 tctx transport context
700 sendfn function for output (transport or verify)
702 Returns: TRUE on success; FALSE on failure.
705 transport_headers_send(transport_ctx * tctx,
706 BOOL (*sendfn)(transport_ctx * tctx, uschar * s, int len))
709 transport_instance * tblock = tctx ? tctx->tblock : NULL;
710 address_item * addr = tctx ? tctx->addr : NULL;
712 /* Then the message's headers. Don't write any that are flagged as "old";
713 that means they were rewritten, or are a record of envelope rewriting, or
714 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
715 match any entries therein. It is a colon-sep list; expand the items
716 separately and squash any empty ones.
717 Then check addr->prop.remove_headers too, provided that addr is not NULL. */
719 for (header_line * h = header_list; h; h = h->next) if (h->type != htype_old)
721 BOOL include_header = TRUE;
723 list = tblock ? tblock->remove_headers : NULL;
724 for (int i = 0; i < 2; i++) /* For remove_headers && addr->prop.remove_headers */
728 int sep = ':'; /* This is specified as a colon-separated list */
730 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
735 if (!(s = expand_string(s)) && !f.expand_string_forcedfail)
737 errno = ERRNO_CHHEADER_FAIL;
740 len = s ? Ustrlen(s) : 0;
741 if (len && s[len-1] == '*') /* trailing glob */
743 if (strncmpic(h->text, s, len-1) == 0) break;
747 if (strncmpic(h->text, s, len) != 0) continue;
749 while (*ss == ' ' || *ss == '\t') ss++;
750 if (*ss == ':') break;
753 if (s) { include_header = FALSE; break; }
755 if (addr) list = addr->prop.remove_headers;
758 /* If this header is to be output, try to rewrite it if there are rewriting
763 if (tblock && tblock->rewrite_rules)
765 rmark reset_point = store_mark();
768 if ((hh = rewrite_header(h, NULL, NULL, tblock->rewrite_rules,
769 tblock->rewrite_existflags, FALSE)))
771 if (!sendfn(tctx, hh->text, hh->slen)) return FALSE;
772 store_reset(reset_point);
773 continue; /* With the next header line */
777 /* Either no rewriting rules, or it didn't get rewritten */
779 if (!sendfn(tctx, h->text, h->slen)) return FALSE;
785 DEBUG(D_transport) debug_printf("removed header line:\n%s---\n", h->text);
788 /* Add on any address-specific headers. If there are multiple addresses,
789 they will all have the same headers in order to be batched. The headers
790 are chained in reverse order of adding (so several addresses from the
791 same alias might share some of them) but we want to output them in the
792 opposite order. This is a bit tedious, but there shouldn't be very many
793 of them. We just walk the list twice, reversing the pointers each time,
794 but on the second time, write out the items.
796 Headers added to an address by a router are guaranteed to end with a newline.
801 header_line *hprev = addr->prop.extra_headers;
802 header_line *hnext, * h;
803 for (int i = 0; i < 2; i++)
804 for (h = hprev, hprev = NULL; h; h = hnext)
811 if (!sendfn(tctx, h->text, h->slen)) return FALSE;
813 debug_printf("added header line(s):\n%s---\n", h->text);
818 /* If a string containing additional headers exists it is a newline-sep
819 list. Expand each item and write out the result. This is done last so that
820 if it (deliberately or accidentally) isn't in header format, it won't mess
821 up any other headers. An empty string or a forced expansion failure are
822 noops. An added header string from a transport may not end with a newline;
823 add one if it does not. */
825 if (tblock && (list = CUS tblock->add_headers))
830 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
831 if ((s = expand_string(s)))
833 int len = Ustrlen(s);
836 if (!sendfn(tctx, s, len)) return FALSE;
837 if (s[len-1] != '\n' && !sendfn(tctx, US"\n", 1))
841 debug_printf("added header line:\n%s", s);
842 if (s[len-1] != '\n') debug_printf("\n");
843 debug_printf("---\n");
847 else if (!f.expand_string_forcedfail)
848 { errno = ERRNO_CHHEADER_FAIL; return FALSE; }
851 /* Separate headers from body with a blank line */
853 return sendfn(tctx, US"\n", 1);
857 /*************************************************
858 * Write the message *
859 *************************************************/
861 /* This function writes the message to the given file descriptor. The headers
862 are in the in-store data structure, and the rest of the message is in the open
863 file descriptor deliver_datafile. Make sure we start it at the beginning.
865 . If add_return_path is TRUE, a "return-path:" header is added to the message,
866 containing the envelope sender's address.
868 . If add_envelope_to is TRUE, a "envelope-to:" header is added to the message,
869 giving the top-level envelope address that caused this delivery to happen.
871 . If add_delivery_date is TRUE, a "delivery-date:" header is added to the
872 message. It gives the time and date that delivery took place.
874 . If check_string is not null, the start of each line is checked for that
875 string. If it is found, it is replaced by escape_string. This used to be
876 the "from hack" for files, and "smtp_dots" for escaping SMTP dots.
878 . If use_crlf is true, newlines are turned into CRLF (SMTP output).
880 The yield is TRUE if all went well, and FALSE if not. Exit *immediately* after
881 any writing or reading error, leaving the code in errno intact. Error exits
882 can include timeouts for certain transports, which are requested by setting
883 transport_write_timeout non-zero.
887 (fd, msg) Either and fd, to write the message to,
888 or a string: if null write message to allocated space
889 otherwire take content as headers.
890 addr (chain of) addresses (for extra headers), or NULL;
891 only the first address is used
892 tblock optional transport instance block (NULL signifies NULL/0):
893 add_headers a string containing one or more headers to add; it is
894 expanded, and must be in correct RFC 822 format as
895 it is transmitted verbatim; NULL => no additions,
896 and so does empty string or forced expansion fail
897 remove_headers a colon-separated list of headers to remove, or NULL
898 rewrite_rules chain of header rewriting rules
899 rewrite_existflags flags for the rewriting rules
900 options bit-wise options:
901 add_return_path if TRUE, add a "return-path" header
902 add_envelope_to if TRUE, add a "envelope-to" header
903 add_delivery_date if TRUE, add a "delivery-date" header
904 use_crlf if TRUE, turn NL into CR LF
905 end_dot if TRUE, send a terminating "." line at the end
906 no_headers if TRUE, omit the headers
907 no_body if TRUE, omit the body
908 check_string a string to check for at the start of lines, or NULL
909 escape_string a string to insert in front of any check string
910 size_limit if > 0, this is a limit to the size of message written;
911 it is used when returning messages to their senders,
912 and is approximate rather than exact, owing to chunk
915 Returns: TRUE on success; FALSE (with errno) on failure.
916 In addition, the global variable transport_count
917 is incremented by the number of bytes written.
921 internal_transport_write_message(transport_ctx * tctx, int size_limit)
925 /* Initialize pointer in output buffer. */
927 transport_write_reset(tctx->options);
929 /* Set up the data for start-of-line data checking and escaping */
931 if (tctx->check_string && tctx->escape_string)
933 nl_check = tctx->check_string;
934 nl_check_length = Ustrlen(nl_check);
935 nl_escape = tctx->escape_string;
936 nl_escape_length = Ustrlen(nl_escape);
939 /* Whether the escaping mechanism is applied to headers or not is controlled by
940 an option (set for SMTP, not otherwise). Negate the length if not wanted till
941 after the headers. */
943 if (!(tctx->options & topt_escape_headers))
944 nl_check_length = -nl_check_length;
946 /* Write the headers if required, including any that have to be added. If there
947 are header rewriting rules, apply them. The datasource is not the -D spoolfile
948 so temporarily hide the global that adjusts for its format. */
950 if (!(tctx->options & topt_no_headers))
952 BOOL save_wireformat = f.spool_file_wireformat;
953 f.spool_file_wireformat = FALSE;
955 /* Add return-path: if requested. */
957 if (tctx->options & topt_add_return_path)
959 uschar buffer[ADDRESS_MAXLENGTH + 20];
960 int n = sprintf(CS buffer, "Return-path: <%.*s>\n", ADDRESS_MAXLENGTH,
962 if (!write_chunk(tctx, buffer, n)) goto bad;
965 /* Add envelope-to: if requested */
967 if (tctx->options & topt_add_envelope_to)
970 struct aci *plist = NULL;
971 struct aci *dlist = NULL;
972 rmark reset_point = store_mark();
974 if (!write_chunk(tctx, US"Envelope-to: ", 13)) goto bad;
976 /* Pick up from all the addresses. The plist and dlist variables are
977 anchors for lists of addresses already handled; they have to be defined at
978 this level because write_env_to() calls itself recursively. */
980 for (address_item * p = tctx->addr; p; p = p->next)
981 if (!write_env_to(p, &plist, &dlist, &first, tctx))
984 /* Add a final newline and reset the store used for tracking duplicates */
986 if (!write_chunk(tctx, US"\n", 1)) goto bad;
987 store_reset(reset_point);
990 /* Add delivery-date: if requested. */
992 if (tctx->options & topt_add_delivery_date)
994 uschar * s = tod_stamp(tod_full);
996 if ( !write_chunk(tctx, US"Delivery-date: ", 15)
997 || !write_chunk(tctx, s, Ustrlen(s))
998 || !write_chunk(tctx, US"\n", 1)) goto bad;
1001 /* Then the message's headers. Don't write any that are flagged as "old";
1002 that means they were rewritten, or are a record of envelope rewriting, or
1003 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
1004 match any entries therein. Then check addr->prop.remove_headers too, provided that
1005 addr is not NULL. */
1007 if (!transport_headers_send(tctx, &write_chunk))
1010 f.spool_file_wireformat = save_wireformat;
1014 f.spool_file_wireformat = save_wireformat;
1017 /* When doing RFC3030 CHUNKING output, work out how much data would be in a
1018 last-BDAT, consisting of the current write_chunk() output buffer fill
1019 (optimally, all of the headers - but it does not matter if we already had to
1020 flush that buffer with non-last BDAT prependix) plus the amount of body data
1021 (as expanded for CRLF lines). Then create and write BDAT(s), and ensure
1022 that further use of write_chunk() will not prepend BDATs.
1023 The first BDAT written will also first flush any outstanding MAIL and RCPT
1024 commands which were buffered thans to PIPELINING.
1025 Commands go out (using a send()) from a different buffer to data (using a
1026 write()). They might not end up in the same TCP segment, which is
1029 if (tctx->options & topt_use_bdat)
1034 if ((hsize = chunk_ptr - deliver_out_buffer) < 0)
1036 if (!(tctx->options & topt_no_body))
1038 if ((fsize = lseek(deliver_datafile, 0, SEEK_END)) < 0) return FALSE;
1039 fsize -= SPOOL_DATA_START_OFFSET;
1040 if (size_limit > 0 && fsize > size_limit)
1042 size = hsize + fsize;
1043 if (tctx->options & topt_use_crlf && !f.spool_file_wireformat)
1044 size += body_linecount; /* account for CRLF-expansion */
1046 /* With topt_use_bdat we never do dot-stuffing; no need to
1047 account for any expansion due to that. */
1050 /* If the message is large, emit first a non-LAST chunk with just the
1051 headers, and reap the command responses. This lets us error out early
1052 on RCPT rejects rather than sending megabytes of data. Include headers
1053 on the assumption they are cheap enough and some clever implementations
1054 might errorcheck them too, on-the-fly, and reject that chunk. */
1056 if (size > DELIVER_OUT_BUFFER_SIZE && hsize > 0)
1059 debug_printf("sending small initial BDAT; hsize=%d\n", hsize);
1060 if ( tctx->chunk_cb(tctx, hsize, 0) != OK
1061 || !transport_write_block(tctx, deliver_out_buffer, hsize, FALSE)
1062 || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
1065 chunk_ptr = deliver_out_buffer;
1069 /* Emit a LAST datachunk command, and unmark the context for further
1072 if (tctx->chunk_cb(tctx, size, tc_chunk_last) != OK)
1074 tctx->options &= ~topt_use_bdat;
1077 /* If the body is required, ensure that the data for check strings (formerly
1078 the "from hack") is enabled by negating the length if necessary. (It will be
1079 negative in cases where it isn't to apply to the headers). Then ensure the body
1080 is positioned at the start of its file (following the message id), then write
1081 it, applying the size limit if required. */
1083 /* If we have a wireformat -D file (CRNL lines, non-dotstuffed, no ending dot)
1084 and we want to send a body without dotstuffing or ending-dot, in-clear,
1085 then we can just dump it using sendfile.
1086 This should get used for CHUNKING output and also for writing the -K file for
1087 dkim signing, when we had CHUNKING input. */
1090 if ( f.spool_file_wireformat
1091 && !(tctx->options & (topt_no_body | topt_end_dot))
1093 && tls_out.active.sock != tctx->u.fd
1097 off_t offset = SPOOL_DATA_START_OFFSET;
1099 /* Write out any header data in the buffer */
1101 if ((len = chunk_ptr - deliver_out_buffer) > 0)
1103 if (!transport_write_block(tctx, deliver_out_buffer, len, TRUE))
1108 DEBUG(D_transport) debug_printf("using sendfile for body\n");
1112 if ((copied = os_sendfile(tctx->u.fd, deliver_datafile, &offset, size)) <= 0) break;
1118 DEBUG(D_transport) debug_printf("cannot use sendfile for body: no support\n");
1122 if (!(tctx->options & topt_no_body))
1123 debug_printf("cannot use sendfile for body: %s\n",
1124 !f.spool_file_wireformat ? "spoolfile not wireformat"
1125 : tctx->options & topt_end_dot ? "terminating dot wanted"
1126 : nl_check_length ? "dot- or From-stuffing wanted"
1127 : "TLS output wanted");
1129 if (!(tctx->options & topt_no_body))
1131 unsigned long size = size_limit > 0 ? size_limit : ULONG_MAX;
1133 nl_check_length = abs(nl_check_length);
1134 nl_partial_match = 0;
1135 if (lseek(deliver_datafile, SPOOL_DATA_START_OFFSET, SEEK_SET) < 0)
1137 while ( (len = MIN(DELIVER_IN_BUFFER_SIZE, size)) > 0
1138 && (len = read(deliver_datafile, deliver_in_buffer, len)) > 0)
1140 if (!write_chunk(tctx, deliver_in_buffer, len))
1145 /* A read error on the body will have left len == -1 and errno set. */
1147 if (len != 0) return FALSE;
1150 /* Finished with the check string, and spool-format consideration */
1152 nl_check_length = nl_escape_length = 0;
1153 f.spool_file_wireformat = FALSE;
1155 /* If requested, add a terminating "." line (SMTP output). */
1157 if (tctx->options & topt_end_dot && !write_chunk(tctx, US".\n", 2))
1160 /* Write out any remaining data in the buffer before returning. */
1162 return (len = chunk_ptr - deliver_out_buffer) <= 0 ||
1163 transport_write_block(tctx, deliver_out_buffer, len, FALSE);
1169 /*************************************************
1170 * External interface to write the message *
1171 *************************************************/
1173 /* If there is no filtering required, call the internal function above to do
1174 the real work, passing over all the arguments from this function. Otherwise,
1175 set up a filtering process, fork another process to call the internal function
1176 to write to the filter, and in this process just suck from the filter and write
1177 down the fd in the transport context. At the end, tidy up the pipes and the
1180 Arguments: as for internal_transport_write_message() above
1182 Returns: TRUE on success; FALSE (with errno) for any failure
1183 transport_count is incremented by the number of bytes written
1187 transport_write_message(transport_ctx * tctx, int size_limit)
1189 BOOL last_filter_was_NL = TRUE;
1190 BOOL save_spool_file_wireformat = f.spool_file_wireformat;
1191 int rc, len, yield, fd_read, fd_write, save_errno;
1192 int pfd[2] = {-1, -1};
1193 pid_t filter_pid, write_pid;
1195 f.transport_filter_timed_out = FALSE;
1197 /* If there is no filter command set up, call the internal function that does
1198 the actual work, passing it the incoming fd, and return its result. */
1200 if ( !transport_filter_argv
1201 || !*transport_filter_argv
1202 || !**transport_filter_argv
1204 return internal_transport_write_message(tctx, size_limit);
1206 /* Otherwise the message must be written to a filter process and read back
1207 before being written to the incoming fd. First set up the special processing to
1208 be done during the copying. */
1210 nl_partial_match = -1;
1212 if (tctx->check_string && tctx->escape_string)
1214 nl_check = tctx->check_string;
1215 nl_check_length = Ustrlen(nl_check);
1216 nl_escape = tctx->escape_string;
1217 nl_escape_length = Ustrlen(nl_escape);
1219 else nl_check_length = nl_escape_length = 0;
1221 /* Start up a subprocess to run the command. Ensure that our main fd will
1222 be closed when the subprocess execs, but remove the flag afterwards.
1223 (Otherwise, if this is a TCP/IP socket, it can't get passed on to another
1224 process to deliver another message.) We get back stdin/stdout file descriptors.
1225 If the process creation failed, give an error return. */
1231 write_pid = (pid_t)(-1);
1234 int bits = fcntl(tctx->u.fd, F_GETFD);
1235 (void)fcntl(tctx->u.fd, F_SETFD, bits | FD_CLOEXEC);
1236 filter_pid = child_open(USS transport_filter_argv, NULL, 077,
1237 &fd_write, &fd_read, FALSE);
1238 (void)fcntl(tctx->u.fd, F_SETFD, bits & ~FD_CLOEXEC);
1240 if (filter_pid < 0) goto TIDY_UP; /* errno set */
1243 debug_printf("process %d running as transport filter: fd_write=%d fd_read=%d\n",
1244 (int)filter_pid, fd_write, fd_read);
1246 /* Fork subprocess to write the message to the filter, and return the result
1247 via a(nother) pipe. While writing to the filter, we do not do the CRLF,
1248 smtp dots, or check string processing. */
1250 if (pipe(pfd) != 0) goto TIDY_UP; /* errno set */
1251 if ((write_pid = fork()) == 0)
1254 (void)close(fd_read);
1255 (void)close(pfd[pipe_read]);
1256 nl_check_length = nl_escape_length = 0;
1258 tctx->u.fd = fd_write;
1259 tctx->check_string = tctx->escape_string = NULL;
1260 tctx->options &= ~(topt_use_crlf | topt_end_dot | topt_use_bdat);
1262 rc = internal_transport_write_message(tctx, size_limit);
1265 if ( write(pfd[pipe_write], (void *)&rc, sizeof(BOOL))
1267 || write(pfd[pipe_write], (void *)&save_errno, sizeof(int))
1269 || write(pfd[pipe_write], (void *)&tctx->addr->more_errno, sizeof(int))
1271 || write(pfd[pipe_write], (void *)&tctx->addr->delivery_time, sizeof(struct timeval))
1272 != sizeof(struct timeval)
1274 rc = FALSE; /* compiler quietening */
1275 exim_underbar_exit(0);
1279 /* Parent process: close our copy of the writing subprocess' pipes. */
1281 (void)close(pfd[pipe_write]);
1282 (void)close(fd_write);
1285 /* Writing process creation failed */
1289 errno = save_errno; /* restore */
1293 /* When testing, let the subprocess get going */
1295 testharness_pause_ms(250);
1298 debug_printf("process %d writing to transport filter\n", (int)write_pid);
1300 /* Copy the message from the filter to the output fd. A read error leaves len
1301 == -1 and errno set. We need to apply a timeout to the read, to cope with
1302 the case when the filter gets stuck, but it can be quite a long one. The
1303 default is 5m, but this is now configurable. */
1305 DEBUG(D_transport) debug_printf("copying from the filter\n");
1307 /* Copy the output of the filter, remembering if the last character was NL. If
1308 no data is returned, that counts as "ended with NL" (default setting of the
1309 variable is TRUE). The output should always be unix-format as we converted
1310 any wireformat source on writing input to the filter. */
1312 f.spool_file_wireformat = FALSE;
1313 chunk_ptr = deliver_out_buffer;
1317 sigalrm_seen = FALSE;
1318 ALARM(transport_filter_timeout);
1319 len = read(fd_read, deliver_in_buffer, DELIVER_IN_BUFFER_SIZE);
1324 f.transport_filter_timed_out = TRUE;
1328 /* If the read was successful, write the block down the original fd,
1329 remembering whether it ends in \n or not. */
1333 if (!write_chunk(tctx, deliver_in_buffer, len)) goto TIDY_UP;
1334 last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
1337 /* Otherwise, break the loop. If we have hit EOF, set yield = TRUE. */
1341 if (len == 0) yield = TRUE;
1346 /* Tidying up code. If yield = FALSE there has been an error and errno is set
1347 to something. Ensure the pipes are all closed and the processes are removed. If
1348 there has been an error, kill the processes before waiting for them, just to be
1349 sure. Also apply a paranoia timeout. */
1352 f.spool_file_wireformat = save_spool_file_wireformat;
1355 (void)close(fd_read);
1356 if (fd_write > 0) (void)close(fd_write);
1360 if (filter_pid > 0) kill(filter_pid, SIGKILL);
1361 if (write_pid > 0) kill(write_pid, SIGKILL);
1364 /* Wait for the filter process to complete. */
1366 DEBUG(D_transport) debug_printf("waiting for filter process\n");
1367 if (filter_pid > 0 && (rc = child_close(filter_pid, 30)) != 0 && yield)
1370 save_errno = ERRNO_FILTER_FAIL;
1371 tctx->addr->more_errno = rc;
1372 DEBUG(D_transport) debug_printf("filter process returned %d\n", rc);
1375 /* Wait for the writing process to complete. If it ends successfully,
1376 read the results from its pipe, provided we haven't already had a filter
1379 DEBUG(D_transport) debug_printf("waiting for writing process\n");
1382 rc = child_close(write_pid, 30);
1387 if (read(pfd[pipe_read], (void *)&ok, sizeof(BOOL)) != sizeof(BOOL))
1390 debug_printf("pipe read from writing process: %s\n", strerror(errno));
1391 save_errno = ERRNO_FILTER_FAIL;
1396 int dummy = read(pfd[pipe_read], (void *)&save_errno, sizeof(int));
1397 dummy = read(pfd[pipe_read], (void *)&tctx->addr->more_errno, sizeof(int));
1398 dummy = read(pfd[pipe_read], (void *)&tctx->addr->delivery_time, sizeof(struct timeval));
1399 dummy = dummy; /* compiler quietening */
1406 save_errno = ERRNO_FILTER_FAIL;
1407 tctx->addr->more_errno = rc;
1408 DEBUG(D_transport) debug_printf("writing process returned %d\n", rc);
1411 (void)close(pfd[pipe_read]);
1413 /* If there have been no problems we can now add the terminating "." if this is
1414 SMTP output, turning off escaping beforehand. If the last character from the
1415 filter was not NL, insert a NL to make the SMTP protocol work. */
1419 nl_check_length = nl_escape_length = 0;
1420 f.spool_file_wireformat = FALSE;
1421 if ( tctx->options & topt_end_dot
1422 && ( last_filter_was_NL
1423 ? !write_chunk(tctx, US".\n", 2)
1424 : !write_chunk(tctx, US"\n.\n", 3)
1428 /* Write out any remaining data in the buffer. */
1431 yield = (len = chunk_ptr - deliver_out_buffer) <= 0
1432 || transport_write_block(tctx, deliver_out_buffer, len, FALSE);
1435 errno = save_errno; /* From some earlier error */
1439 debug_printf("end of filtering transport writing: yield=%d\n", yield);
1441 debug_printf("errno=%d more_errno=%d\n", errno, tctx->addr->more_errno);
1451 /*************************************************
1452 * Update waiting database *
1453 *************************************************/
1455 /* This is called when an address is deferred by remote transports that are
1456 capable of sending more than one message over one connection. A database is
1457 maintained for each transport, keeping track of which messages are waiting for
1458 which hosts. The transport can then consult this when eventually a successful
1459 delivery happens, and if it finds that another message is waiting for the same
1460 host, it can fire up a new process to deal with it using the same connection.
1462 The database records are keyed by host name. They can get full if there are
1463 lots of messages waiting, and so there is a continuation mechanism for them.
1465 Each record contains a list of message ids, packed end to end without any
1466 zeros. Each one is MESSAGE_ID_LENGTH bytes long. The count field says how many
1467 in this record, and the sequence field says if there are any other records for
1468 this host. If the sequence field is 0, there are none. If it is 1, then another
1469 record with the name <hostname>:0 exists; if it is 2, then two other records
1470 with sequence numbers 0 and 1 exist, and so on.
1472 Currently, an exhaustive search of all continuation records has to be done to
1473 determine whether to add a message id to a given record. This shouldn't be
1474 too bad except in extreme cases. I can't figure out a *simple* way of doing
1477 Old records should eventually get swept up by the exim_tidydb utility.
1480 hostlist list of hosts that this message could be sent to
1481 tpname name of the transport
1487 transport_update_waiting(host_item *hostlist, uschar *tpname)
1489 const uschar *prevname = US"";
1493 DEBUG(D_transport) debug_printf("updating wait-%s database\n", tpname);
1495 /* Open the database for this transport */
1497 if (!(dbm_file = dbfn_open(string_sprintf("wait-%.200s", tpname),
1498 O_RDWR, &dbblock, TRUE, TRUE)))
1501 /* Scan the list of hosts for which this message is waiting, and ensure
1502 that the message id is in each host record. */
1504 for (host_item * host = hostlist; host; host = host->next)
1506 BOOL already = FALSE;
1507 dbdata_wait *host_record;
1511 /* Skip if this is the same host as we just processed; otherwise remember
1512 the name for next time. */
1514 if (Ustrcmp(prevname, host->name) == 0) continue;
1515 prevname = host->name;
1517 /* Look up the host record; if there isn't one, make an empty one. */
1519 if (!(host_record = dbfn_read(dbm_file, host->name)))
1521 host_record = store_get(sizeof(dbdata_wait) + MESSAGE_ID_LENGTH, FALSE);
1522 host_record->count = host_record->sequence = 0;
1525 /* Compute the current length */
1527 host_length = host_record->count * MESSAGE_ID_LENGTH;
1529 /* Search the record to see if the current message is already in it. */
1531 for (uschar * s = host_record->text; s < host_record->text + host_length;
1532 s += MESSAGE_ID_LENGTH)
1533 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1534 { already = TRUE; break; }
1536 /* If we haven't found this message in the main record, search any
1537 continuation records that exist. */
1539 for (int i = host_record->sequence - 1; i >= 0 && !already; i--)
1542 sprintf(CS buffer, "%.200s:%d", host->name, i);
1543 if ((cont = dbfn_read(dbm_file, buffer)))
1545 int clen = cont->count * MESSAGE_ID_LENGTH;
1546 for (uschar * s = cont->text; s < cont->text + clen; s += MESSAGE_ID_LENGTH)
1547 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1548 { already = TRUE; break; }
1552 /* If this message is already in a record, no need to update. */
1556 DEBUG(D_transport) debug_printf("already listed for %s\n", host->name);
1561 /* If this record is full, write it out with a new name constructed
1562 from the sequence number, increase the sequence number, and empty
1565 if (host_record->count >= WAIT_NAME_MAX)
1567 sprintf(CS buffer, "%.200s:%d", host->name, host_record->sequence);
1568 dbfn_write(dbm_file, buffer, host_record, sizeof(dbdata_wait) + host_length);
1569 host_record->sequence++;
1570 host_record->count = 0;
1574 /* If this record is not full, increase the size of the record to
1575 allow for one new message id. */
1580 store_get(sizeof(dbdata_wait) + host_length + MESSAGE_ID_LENGTH, FALSE);
1581 memcpy(newr, host_record, sizeof(dbdata_wait) + host_length);
1585 /* Now add the new name on the end */
1587 memcpy(host_record->text + host_length, message_id, MESSAGE_ID_LENGTH);
1588 host_record->count++;
1589 host_length += MESSAGE_ID_LENGTH;
1591 /* Update the database */
1593 dbfn_write(dbm_file, host->name, host_record, sizeof(dbdata_wait) + host_length);
1594 DEBUG(D_transport) debug_printf("added to list for %s\n", host->name);
1599 dbfn_close(dbm_file);
1605 /*************************************************
1606 * Test for waiting messages *
1607 *************************************************/
1609 /* This function is called by a remote transport which uses the previous
1610 function to remember which messages are waiting for which remote hosts. It's
1611 called after a successful delivery and its job is to check whether there is
1612 another message waiting for the same host. However, it doesn't do this if the
1613 current continue sequence is greater than the maximum supplied as an argument,
1614 or greater than the global connection_max_messages, which, if set, overrides.
1617 transport_name name of the transport
1618 hostname name of the host
1619 local_message_max maximum number of messages down one connection
1620 as set by the caller transport
1621 new_message_id set to the message id of a waiting message
1622 more set TRUE if there are yet more messages waiting
1623 oicf_func function to call to validate if it is ok to send
1624 to this message_id from the current instance.
1625 oicf_data opaque data for oicf_func
1627 Returns: TRUE if new_message_id set; FALSE otherwise
1630 typedef struct msgq_s
1632 uschar message_id [MESSAGE_ID_LENGTH + 1];
1637 transport_check_waiting(const uschar *transport_name, const uschar *hostname,
1638 int local_message_max, uschar *new_message_id, BOOL *more, oicf oicf_func, void *oicf_data)
1640 dbdata_wait *host_record;
1646 struct stat statbuf;
1652 debug_printf("transport_check_waiting entered\n");
1653 debug_printf(" sequence=%d local_max=%d global_max=%d\n",
1654 continue_sequence, local_message_max, connection_max_messages);
1657 /* Do nothing if we have hit the maximum number that can be send down one
1660 if (connection_max_messages >= 0) local_message_max = connection_max_messages;
1661 if (local_message_max > 0 && continue_sequence >= local_message_max)
1664 debug_printf("max messages for one connection reached: returning\n");
1668 /* Open the waiting information database. */
1670 if (!(dbm_file = dbfn_open(string_sprintf("wait-%.200s", transport_name),
1671 O_RDWR, &dbblock, TRUE, TRUE)))
1674 /* See if there is a record for this host; if not, there's nothing to do. */
1676 if (!(host_record = dbfn_read(dbm_file, hostname)))
1678 dbfn_close(dbm_file);
1679 DEBUG(D_transport) debug_printf("no messages waiting for %s\n", hostname);
1683 /* If the data in the record looks corrupt, just log something and
1684 don't try to use it. */
1686 if (host_record->count > WAIT_NAME_MAX)
1688 dbfn_close(dbm_file);
1689 log_write(0, LOG_MAIN|LOG_PANIC, "smtp-wait database entry for %s has bad "
1690 "count=%d (max=%d)", hostname, host_record->count, WAIT_NAME_MAX);
1694 /* Scan the message ids in the record from the end towards the beginning,
1695 until one is found for which a spool file actually exists. If the record gets
1696 emptied, delete it and continue with any continuation records that may exist.
1699 /* For Bug 1141, I refactored this major portion of the routine, it is risky
1700 but the 1 off will remain without it. This code now allows me to SKIP over
1701 a message I do not want to send out on this run. */
1703 host_length = host_record->count * MESSAGE_ID_LENGTH;
1709 int msgq_actual = 0;
1710 BOOL bFound = FALSE;
1711 BOOL bContinuation = FALSE;
1713 /* create an array to read entire message queue into memory for processing */
1715 msgq = store_get(sizeof(msgq_t) * host_record->count, FALSE);
1716 msgq_count = host_record->count;
1717 msgq_actual = msgq_count;
1719 for (i = 0; i < host_record->count; ++i)
1721 msgq[i].bKeep = TRUE;
1723 Ustrncpy_nt(msgq[i].message_id, host_record->text + (i * MESSAGE_ID_LENGTH),
1725 msgq[i].message_id[MESSAGE_ID_LENGTH] = 0;
1728 /* first thing remove current message id if it exists */
1730 for (i = 0; i < msgq_count; ++i)
1731 if (Ustrcmp(msgq[i].message_id, message_id) == 0)
1733 msgq[i].bKeep = FALSE;
1737 /* now find the next acceptable message_id */
1739 for (i = msgq_count - 1; i >= 0; --i) if (msgq[i].bKeep)
1742 uschar * mid = msgq[i].message_id;
1744 set_subdir_str(subdir, mid, 0);
1745 if (Ustat(spool_fname(US"input", subdir, mid, US"-D"), &statbuf) != 0)
1746 msgq[i].bKeep = FALSE;
1747 else if (!oicf_func || oicf_func(mid, oicf_data))
1749 Ustrcpy_nt(new_message_id, mid);
1750 msgq[i].bKeep = FALSE;
1757 for (msgq_actual = 0, i = 0; i < msgq_count; ++i)
1761 /* reassemble the host record, based on removed message ids, from in
1764 if (msgq_actual <= 0)
1767 host_record->count = 0;
1771 host_length = msgq_actual * MESSAGE_ID_LENGTH;
1772 host_record->count = msgq_actual;
1774 if (msgq_actual < msgq_count)
1777 for (new_count = 0, i = 0; i < msgq_count; ++i)
1779 Ustrncpy(&host_record->text[new_count++ * MESSAGE_ID_LENGTH],
1780 msgq[i].message_id, MESSAGE_ID_LENGTH);
1782 host_record->text[new_count * MESSAGE_ID_LENGTH] = 0;
1786 /* Check for a continuation record. */
1788 while (host_length <= 0)
1790 dbdata_wait * newr = NULL;
1793 /* Search for a continuation */
1795 for (int i = host_record->sequence - 1; i >= 0 && !newr; i--)
1797 sprintf(CS buffer, "%.200s:%d", hostname, i);
1798 newr = dbfn_read(dbm_file, buffer);
1801 /* If no continuation, delete the current and break the loop */
1805 dbfn_delete(dbm_file, hostname);
1809 /* Else replace the current with the continuation */
1811 dbfn_delete(dbm_file, buffer);
1813 host_length = host_record->count * MESSAGE_ID_LENGTH;
1815 bContinuation = TRUE;
1818 if (bFound) /* Usual exit from main loop */
1821 /* If host_length <= 0 we have emptied a record and not found a good message,
1822 and there are no continuation records. Otherwise there is a continuation
1823 record to process. */
1825 if (host_length <= 0)
1827 dbfn_close(dbm_file);
1828 DEBUG(D_transport) debug_printf("waiting messages already delivered\n");
1832 /* we were not able to find an acceptable message, nor was there a
1833 * continuation record. So bug out, outer logic will clean this up.
1838 Ustrcpy(new_message_id, message_id);
1839 dbfn_close(dbm_file);
1842 } /* we need to process a continuation record */
1844 /* Control gets here when an existing message has been encountered; its
1845 id is in new_message_id, and host_length is the revised length of the
1846 host record. If it is zero, the record has been removed. Update the
1847 record if required, close the database, and return TRUE. */
1849 if (host_length > 0)
1851 host_record->count = host_length/MESSAGE_ID_LENGTH;
1853 dbfn_write(dbm_file, hostname, host_record, (int)sizeof(dbdata_wait) + host_length);
1857 dbfn_close(dbm_file);
1861 /*************************************************
1862 * Deliver waiting message down same socket *
1863 *************************************************/
1865 /* Just the regain-root-privilege exec portion */
1867 transport_do_pass_socket(const uschar *transport_name, const uschar *hostname,
1868 const uschar *hostaddress, uschar *id, int socket_fd)
1871 const uschar **argv;
1873 /* Set up the calling arguments; use the standard function for the basics,
1874 but we have a number of extras that may be added. */
1876 argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, &i, FALSE, 0);
1878 if (f.smtp_authenticated) argv[i++] = US"-MCA";
1879 if (smtp_peer_options & OPTION_CHUNKING) argv[i++] = US"-MCK";
1880 if (smtp_peer_options & OPTION_DSN) argv[i++] = US"-MCD";
1881 if (smtp_peer_options & OPTION_PIPE) argv[i++] = US"-MCP";
1882 if (smtp_peer_options & OPTION_SIZE) argv[i++] = US"-MCS";
1884 if (smtp_peer_options & OPTION_TLS)
1885 if (tls_out.active.sock >= 0 || continue_proxy_cipher)
1887 argv[i++] = US"-MCt";
1888 argv[i++] = sending_ip_address;
1889 argv[i++] = string_sprintf("%d", sending_port);
1890 argv[i++] = tls_out.active.sock >= 0 ? tls_out.cipher : continue_proxy_cipher;
1893 argv[i++] = US"-MCT";
1896 if (queue_run_pid != (pid_t)0)
1898 argv[i++] = US"-MCQ";
1899 argv[i++] = string_sprintf("%d", queue_run_pid);
1900 argv[i++] = string_sprintf("%d", queue_run_pipe);
1903 argv[i++] = US"-MC";
1904 argv[i++] = US transport_name;
1905 argv[i++] = US hostname;
1906 argv[i++] = US hostaddress;
1907 argv[i++] = string_sprintf("%d", continue_sequence + 1);
1911 /* Arrange for the channel to be on stdin. */
1915 (void)dup2(socket_fd, 0);
1916 (void)close(socket_fd);
1919 DEBUG(D_exec) debug_print_argv(argv);
1920 exim_nullstd(); /* Ensure std{out,err} exist */
1921 execv(CS argv[0], (char *const *)argv);
1923 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
1924 _exit(errno); /* Note: must be _exit(), NOT exit() */
1929 /* Fork a new exim process to deliver the message, and do a re-exec, both to
1930 get a clean delivery process, and to regain root privilege in cases where it
1931 has been given away.
1934 transport_name to pass to the new process
1937 id the new message to process
1938 socket_fd the connected socket
1940 Returns: FALSE if fork fails; TRUE otherwise
1944 transport_pass_socket(const uschar *transport_name, const uschar *hostname,
1945 const uschar *hostaddress, uschar *id, int socket_fd)
1950 DEBUG(D_transport) debug_printf("transport_pass_socket entered\n");
1952 if ((pid = fork()) == 0)
1954 /* Disconnect entirely from the parent process. If we are running in the
1955 test harness, wait for a bit to allow the previous process time to finish,
1956 write the log, etc., so that the output is always in the same order for
1957 automatic comparison. */
1959 if ((pid = fork()) != 0)
1961 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded (final-pid %d)\n", pid);
1962 _exit(EXIT_SUCCESS);
1964 testharness_pause_ms(1000);
1966 transport_do_pass_socket(transport_name, hostname, hostaddress,
1970 /* If the process creation succeeded, wait for the first-level child, which
1971 immediately exits, leaving the second level process entirely disconnected from
1977 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
1978 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded (inter-pid %d)\n", pid);
1983 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
1991 /*************************************************
1992 * Set up direct (non-shell) command *
1993 *************************************************/
1995 /* This function is called when a command line is to be parsed and executed
1996 directly, without the use of /bin/sh. It is called by the pipe transport,
1997 the queryprogram router, and also from the main delivery code when setting up a
1998 transport filter process. The code for ETRN also makes use of this; in that
1999 case, no addresses are passed.
2002 argvptr pointer to anchor for argv vector
2003 cmd points to the command string (modified IN PLACE)
2004 expand_arguments true if expansion is to occur
2005 expand_failed error value to set if expansion fails; not relevant if
2007 addr chain of addresses, or NULL
2008 etext text for use in error messages
2009 errptr where to put error message if addr is NULL;
2010 otherwise it is put in the first address
2012 Returns: TRUE if all went well; otherwise an error will be
2013 set in the first address and FALSE returned
2017 transport_set_up_command(const uschar ***argvptr, uschar *cmd,
2018 BOOL expand_arguments, int expand_failed, address_item *addr,
2019 uschar *etext, uschar **errptr)
2021 const uschar **argv;
2023 int address_count = 0;
2027 /* Get store in which to build an argument list. Count the number of addresses
2028 supplied, and allow for that many arguments, plus an additional 60, which
2029 should be enough for anybody. Multiple addresses happen only when the local
2030 delivery batch option is set. */
2032 for (address_item * ad = addr; ad; ad = ad->next) address_count++;
2033 max_args = address_count + 60;
2034 *argvptr = argv = store_get((max_args+1)*sizeof(uschar *), FALSE);
2036 /* Split the command up into arguments terminated by white space. Lose
2037 trailing space at the start and end. Double-quoted arguments can contain \\ and
2038 \" escapes and so can be handled by the standard function; single-quoted
2039 arguments are verbatim. Copy each argument into a new string. */
2042 while (isspace(*s)) s++;
2044 for (; *s != 0 && argcount < max_args; argcount++)
2049 while (*ss != 0 && *ss != '\'') ss++;
2050 argv[argcount] = ss = store_get(ss - s++, is_tainted(cmd));
2051 while (*s != 0 && *s != '\'') *ss++ = *s++;
2056 argv[argcount] = string_dequote(CUSS &s);
2057 while (isspace(*s)) s++;
2060 argv[argcount] = US 0;
2062 /* If *s != 0 we have run out of argument slots. */
2066 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
2070 addr->transport_return = FAIL;
2071 addr->message = msg;
2077 /* Expand each individual argument if required. Expansion happens for pipes set
2078 up in filter files and with directly-supplied commands. It does not happen if
2079 the pipe comes from a traditional .forward file. A failing expansion is a big
2080 disaster if the command came from Exim's configuration; if it came from a user
2081 it is just a normal failure. The expand_failed value is used as the error value
2082 to cater for these two cases.
2084 An argument consisting just of the text "$pipe_addresses" is treated specially.
2085 It is not passed to the general expansion function. Instead, it is replaced by
2086 a number of arguments, one for each address. This avoids problems with shell
2087 metacharacters and spaces in addresses.
2089 If the parent of the top address has an original part of "system-filter", this
2090 pipe was set up by the system filter, and we can permit the expansion of
2095 debug_printf("direct command:\n");
2096 for (int i = 0; argv[i]; i++)
2097 debug_printf(" argv[%d] = '%s'\n", i, string_printing(argv[i]));
2100 if (expand_arguments)
2102 BOOL allow_dollar_recipients = addr != NULL &&
2103 addr->parent != NULL &&
2104 Ustrcmp(addr->parent->address, "system-filter") == 0;
2106 for (int i = 0; argv[i] != US 0; i++)
2109 /* Handle special fudge for passing an address list */
2112 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
2113 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
2117 if (argcount + address_count - 1 > max_args)
2119 addr->transport_return = FAIL;
2120 addr->message = string_sprintf("Too many arguments to command \"%s\" "
2121 "in %s", cmd, etext);
2125 additional = address_count - 1;
2127 memmove(argv + i + 1 + additional, argv + i + 1,
2128 (argcount - i)*sizeof(uschar *));
2130 for (address_item * ad = addr; ad; ad = ad->next)
2132 argv[i++] = ad->address;
2136 /* Subtract one since we replace $pipe_addresses */
2141 /* Handle special case of $address_pipe when af_force_command is set */
2143 else if (addr != NULL && testflag(addr,af_force_command) &&
2144 (Ustrcmp(argv[i], "$address_pipe") == 0 ||
2145 Ustrcmp(argv[i], "${address_pipe}") == 0))
2147 int address_pipe_argcount = 0;
2148 int address_pipe_max_args;
2149 uschar **address_pipe_argv;
2152 /* We can never have more then the argv we will be loading into */
2153 address_pipe_max_args = max_args - argcount + 1;
2156 debug_printf("address_pipe_max_args=%d\n", address_pipe_max_args);
2158 /* We allocate an additional for (uschar *)0 */
2159 address_pipe_argv = store_get((address_pipe_max_args+1)*sizeof(uschar *), FALSE);
2161 /* +1 because addr->local_part[0] == '|' since af_force_command is set */
2162 s = expand_string(addr->local_part + 1);
2163 tainted = is_tainted(s);
2165 if (s == NULL || *s == '\0')
2167 addr->transport_return = FAIL;
2168 addr->message = string_sprintf("Expansion of \"%s\" "
2169 "from command \"%s\" in %s failed: %s",
2170 (addr->local_part + 1), cmd, etext, expand_string_message);
2174 while (isspace(*s)) s++; /* strip leading space */
2176 while (*s != 0 && address_pipe_argcount < address_pipe_max_args)
2181 while (*ss != 0 && *ss != '\'') ss++;
2182 address_pipe_argv[address_pipe_argcount++] = ss = store_get(ss - s++, tainted);
2183 while (*s != 0 && *s != '\'') *ss++ = *s++;
2187 else address_pipe_argv[address_pipe_argcount++] =
2188 string_copy(string_dequote(CUSS &s));
2189 while (isspace(*s)) s++; /* strip space after arg */
2192 address_pipe_argv[address_pipe_argcount] = US 0;
2194 /* If *s != 0 we have run out of argument slots. */
2197 uschar *msg = string_sprintf("Too many arguments in $address_pipe "
2198 "\"%s\" in %s", addr->local_part + 1, etext);
2201 addr->transport_return = FAIL;
2202 addr->message = msg;
2208 /* address_pipe_argcount - 1
2209 * because we are replacing $address_pipe in the argument list
2210 * with the first thing it expands to */
2211 if (argcount + address_pipe_argcount - 1 > max_args)
2213 addr->transport_return = FAIL;
2214 addr->message = string_sprintf("Too many arguments to command "
2215 "\"%s\" after expanding $address_pipe in %s", cmd, etext);
2219 /* If we are not just able to replace the slot that contained
2220 * $address_pipe (address_pipe_argcount == 1)
2221 * We have to move the existing argv by address_pipe_argcount - 1
2222 * Visually if address_pipe_argcount == 2:
2223 * [argv 0][argv 1][argv 2($address_pipe)][argv 3][0]
2224 * [argv 0][argv 1][ap_arg0][ap_arg1][old argv 3][0]
2226 if (address_pipe_argcount > 1)
2228 /* current position + additional args */
2229 argv + i + address_pipe_argcount,
2230 /* current position + 1 (for the (uschar *)0 at the end) */
2232 /* -1 for the (uschar *)0 at the end)*/
2233 (argcount - i)*sizeof(uschar *)
2236 /* Now we fill in the slots we just moved argv out of
2237 * [argv 0][argv 1][argv 2=pipeargv[0]][argv 3=pipeargv[1]][old argv 3][0]
2239 for (int address_pipe_i = 0;
2240 address_pipe_argv[address_pipe_i] != US 0;
2243 argv[i++] = address_pipe_argv[address_pipe_i];
2247 /* Subtract one since we replace $address_pipe */
2252 /* Handle normal expansion string */
2256 const uschar *expanded_arg;
2257 f.enable_dollar_recipients = allow_dollar_recipients;
2258 expanded_arg = expand_cstring(argv[i]);
2259 f.enable_dollar_recipients = FALSE;
2263 uschar *msg = string_sprintf("Expansion of \"%s\" "
2264 "from command \"%s\" in %s failed: %s",
2265 argv[i], cmd, etext, expand_string_message);
2268 addr->transport_return = expand_failed;
2269 addr->message = msg;
2274 argv[i] = expanded_arg;
2280 debug_printf("direct command after expansion:\n");
2281 for (int i = 0; argv[i] != US 0; i++)
2282 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2289 #endif /*!MACRO_PREDEF*/
2292 /* End of transport.c */