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 (strncmpic(h->text, s, len) != 0) continue;
743 while (*ss == ' ' || *ss == '\t') ss++;
744 if (*ss == ':') break;
746 if (s) { include_header = FALSE; break; }
748 if (addr) list = addr->prop.remove_headers;
751 /* If this header is to be output, try to rewrite it if there are rewriting
756 if (tblock && tblock->rewrite_rules)
758 rmark reset_point = store_mark();
761 if ((hh = rewrite_header(h, NULL, NULL, tblock->rewrite_rules,
762 tblock->rewrite_existflags, FALSE)))
764 if (!sendfn(tctx, hh->text, hh->slen)) return FALSE;
765 store_reset(reset_point);
766 continue; /* With the next header line */
770 /* Either no rewriting rules, or it didn't get rewritten */
772 if (!sendfn(tctx, h->text, h->slen)) return FALSE;
778 DEBUG(D_transport) debug_printf("removed header line:\n%s---\n", h->text);
781 /* Add on any address-specific headers. If there are multiple addresses,
782 they will all have the same headers in order to be batched. The headers
783 are chained in reverse order of adding (so several addresses from the
784 same alias might share some of them) but we want to output them in the
785 opposite order. This is a bit tedious, but there shouldn't be very many
786 of them. We just walk the list twice, reversing the pointers each time,
787 but on the second time, write out the items.
789 Headers added to an address by a router are guaranteed to end with a newline.
794 header_line *hprev = addr->prop.extra_headers;
795 header_line *hnext, * h;
796 for (int i = 0; i < 2; i++)
797 for (h = hprev, hprev = NULL; h; h = hnext)
804 if (!sendfn(tctx, h->text, h->slen)) return FALSE;
806 debug_printf("added header line(s):\n%s---\n", h->text);
811 /* If a string containing additional headers exists it is a newline-sep
812 list. Expand each item and write out the result. This is done last so that
813 if it (deliberately or accidentally) isn't in header format, it won't mess
814 up any other headers. An empty string or a forced expansion failure are
815 noops. An added header string from a transport may not end with a newline;
816 add one if it does not. */
818 if (tblock && (list = CUS tblock->add_headers))
823 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
824 if ((s = expand_string(s)))
826 int len = Ustrlen(s);
829 if (!sendfn(tctx, s, len)) return FALSE;
830 if (s[len-1] != '\n' && !sendfn(tctx, US"\n", 1))
834 debug_printf("added header line:\n%s", s);
835 if (s[len-1] != '\n') debug_printf("\n");
836 debug_printf("---\n");
840 else if (!f.expand_string_forcedfail)
841 { errno = ERRNO_CHHEADER_FAIL; return FALSE; }
844 /* Separate headers from body with a blank line */
846 return sendfn(tctx, US"\n", 1);
850 /*************************************************
851 * Write the message *
852 *************************************************/
854 /* This function writes the message to the given file descriptor. The headers
855 are in the in-store data structure, and the rest of the message is in the open
856 file descriptor deliver_datafile. Make sure we start it at the beginning.
858 . If add_return_path is TRUE, a "return-path:" header is added to the message,
859 containing the envelope sender's address.
861 . If add_envelope_to is TRUE, a "envelope-to:" header is added to the message,
862 giving the top-level envelope address that caused this delivery to happen.
864 . If add_delivery_date is TRUE, a "delivery-date:" header is added to the
865 message. It gives the time and date that delivery took place.
867 . If check_string is not null, the start of each line is checked for that
868 string. If it is found, it is replaced by escape_string. This used to be
869 the "from hack" for files, and "smtp_dots" for escaping SMTP dots.
871 . If use_crlf is true, newlines are turned into CRLF (SMTP output).
873 The yield is TRUE if all went well, and FALSE if not. Exit *immediately* after
874 any writing or reading error, leaving the code in errno intact. Error exits
875 can include timeouts for certain transports, which are requested by setting
876 transport_write_timeout non-zero.
880 (fd, msg) Either and fd, to write the message to,
881 or a string: if null write message to allocated space
882 otherwire take content as headers.
883 addr (chain of) addresses (for extra headers), or NULL;
884 only the first address is used
885 tblock optional transport instance block (NULL signifies NULL/0):
886 add_headers a string containing one or more headers to add; it is
887 expanded, and must be in correct RFC 822 format as
888 it is transmitted verbatim; NULL => no additions,
889 and so does empty string or forced expansion fail
890 remove_headers a colon-separated list of headers to remove, or NULL
891 rewrite_rules chain of header rewriting rules
892 rewrite_existflags flags for the rewriting rules
893 options bit-wise options:
894 add_return_path if TRUE, add a "return-path" header
895 add_envelope_to if TRUE, add a "envelope-to" header
896 add_delivery_date if TRUE, add a "delivery-date" header
897 use_crlf if TRUE, turn NL into CR LF
898 end_dot if TRUE, send a terminating "." line at the end
899 no_headers if TRUE, omit the headers
900 no_body if TRUE, omit the body
901 check_string a string to check for at the start of lines, or NULL
902 escape_string a string to insert in front of any check string
903 size_limit if > 0, this is a limit to the size of message written;
904 it is used when returning messages to their senders,
905 and is approximate rather than exact, owing to chunk
908 Returns: TRUE on success; FALSE (with errno) on failure.
909 In addition, the global variable transport_count
910 is incremented by the number of bytes written.
914 internal_transport_write_message(transport_ctx * tctx, int size_limit)
918 /* Initialize pointer in output buffer. */
920 transport_write_reset(tctx->options);
922 /* Set up the data for start-of-line data checking and escaping */
924 if (tctx->check_string && tctx->escape_string)
926 nl_check = tctx->check_string;
927 nl_check_length = Ustrlen(nl_check);
928 nl_escape = tctx->escape_string;
929 nl_escape_length = Ustrlen(nl_escape);
932 /* Whether the escaping mechanism is applied to headers or not is controlled by
933 an option (set for SMTP, not otherwise). Negate the length if not wanted till
934 after the headers. */
936 if (!(tctx->options & topt_escape_headers))
937 nl_check_length = -nl_check_length;
939 /* Write the headers if required, including any that have to be added. If there
940 are header rewriting rules, apply them. The datasource is not the -D spoolfile
941 so temporarily hide the global that adjusts for its format. */
943 if (!(tctx->options & topt_no_headers))
945 BOOL save_wireformat = f.spool_file_wireformat;
946 f.spool_file_wireformat = FALSE;
948 /* Add return-path: if requested. */
950 if (tctx->options & topt_add_return_path)
952 uschar buffer[ADDRESS_MAXLENGTH + 20];
953 int n = sprintf(CS buffer, "Return-path: <%.*s>\n", ADDRESS_MAXLENGTH,
955 if (!write_chunk(tctx, buffer, n)) goto bad;
958 /* Add envelope-to: if requested */
960 if (tctx->options & topt_add_envelope_to)
963 struct aci *plist = NULL;
964 struct aci *dlist = NULL;
965 rmark reset_point = store_mark();
967 if (!write_chunk(tctx, US"Envelope-to: ", 13)) goto bad;
969 /* Pick up from all the addresses. The plist and dlist variables are
970 anchors for lists of addresses already handled; they have to be defined at
971 this level because write_env_to() calls itself recursively. */
973 for (address_item * p = tctx->addr; p; p = p->next)
974 if (!write_env_to(p, &plist, &dlist, &first, tctx))
977 /* Add a final newline and reset the store used for tracking duplicates */
979 if (!write_chunk(tctx, US"\n", 1)) goto bad;
980 store_reset(reset_point);
983 /* Add delivery-date: if requested. */
985 if (tctx->options & topt_add_delivery_date)
987 uschar * s = tod_stamp(tod_full);
989 if ( !write_chunk(tctx, US"Delivery-date: ", 15)
990 || !write_chunk(tctx, s, Ustrlen(s))
991 || !write_chunk(tctx, US"\n", 1)) goto bad;
994 /* Then the message's headers. Don't write any that are flagged as "old";
995 that means they were rewritten, or are a record of envelope rewriting, or
996 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
997 match any entries therein. Then check addr->prop.remove_headers too, provided that
1000 if (!transport_headers_send(tctx, &write_chunk))
1003 f.spool_file_wireformat = save_wireformat;
1007 f.spool_file_wireformat = save_wireformat;
1010 /* When doing RFC3030 CHUNKING output, work out how much data would be in a
1011 last-BDAT, consisting of the current write_chunk() output buffer fill
1012 (optimally, all of the headers - but it does not matter if we already had to
1013 flush that buffer with non-last BDAT prependix) plus the amount of body data
1014 (as expanded for CRLF lines). Then create and write BDAT(s), and ensure
1015 that further use of write_chunk() will not prepend BDATs.
1016 The first BDAT written will also first flush any outstanding MAIL and RCPT
1017 commands which were buffered thans to PIPELINING.
1018 Commands go out (using a send()) from a different buffer to data (using a
1019 write()). They might not end up in the same TCP segment, which is
1022 if (tctx->options & topt_use_bdat)
1027 if ((hsize = chunk_ptr - deliver_out_buffer) < 0)
1029 if (!(tctx->options & topt_no_body))
1031 if ((fsize = lseek(deliver_datafile, 0, SEEK_END)) < 0) return FALSE;
1032 fsize -= SPOOL_DATA_START_OFFSET;
1033 if (size_limit > 0 && fsize > size_limit)
1035 size = hsize + fsize;
1036 if (tctx->options & topt_use_crlf && !f.spool_file_wireformat)
1037 size += body_linecount; /* account for CRLF-expansion */
1039 /* With topt_use_bdat we never do dot-stuffing; no need to
1040 account for any expansion due to that. */
1043 /* If the message is large, emit first a non-LAST chunk with just the
1044 headers, and reap the command responses. This lets us error out early
1045 on RCPT rejects rather than sending megabytes of data. Include headers
1046 on the assumption they are cheap enough and some clever implementations
1047 might errorcheck them too, on-the-fly, and reject that chunk. */
1049 if (size > DELIVER_OUT_BUFFER_SIZE && hsize > 0)
1052 debug_printf("sending small initial BDAT; hsize=%d\n", hsize);
1053 if ( tctx->chunk_cb(tctx, hsize, 0) != OK
1054 || !transport_write_block(tctx, deliver_out_buffer, hsize, FALSE)
1055 || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
1058 chunk_ptr = deliver_out_buffer;
1062 /* Emit a LAST datachunk command, and unmark the context for further
1065 if (tctx->chunk_cb(tctx, size, tc_chunk_last) != OK)
1067 tctx->options &= ~topt_use_bdat;
1070 /* If the body is required, ensure that the data for check strings (formerly
1071 the "from hack") is enabled by negating the length if necessary. (It will be
1072 negative in cases where it isn't to apply to the headers). Then ensure the body
1073 is positioned at the start of its file (following the message id), then write
1074 it, applying the size limit if required. */
1076 /* If we have a wireformat -D file (CRNL lines, non-dotstuffed, no ending dot)
1077 and we want to send a body without dotstuffing or ending-dot, in-clear,
1078 then we can just dump it using sendfile.
1079 This should get used for CHUNKING output and also for writing the -K file for
1080 dkim signing, when we had CHUNKING input. */
1083 if ( f.spool_file_wireformat
1084 && !(tctx->options & (topt_no_body | topt_end_dot))
1086 && tls_out.active.sock != tctx->u.fd
1090 off_t offset = SPOOL_DATA_START_OFFSET;
1092 /* Write out any header data in the buffer */
1094 if ((len = chunk_ptr - deliver_out_buffer) > 0)
1096 if (!transport_write_block(tctx, deliver_out_buffer, len, TRUE))
1101 DEBUG(D_transport) debug_printf("using sendfile for body\n");
1105 if ((copied = os_sendfile(tctx->u.fd, deliver_datafile, &offset, size)) <= 0) break;
1111 DEBUG(D_transport) debug_printf("cannot use sendfile for body: no support\n");
1115 if (!(tctx->options & topt_no_body))
1116 debug_printf("cannot use sendfile for body: %s\n",
1117 !f.spool_file_wireformat ? "spoolfile not wireformat"
1118 : tctx->options & topt_end_dot ? "terminating dot wanted"
1119 : nl_check_length ? "dot- or From-stuffing wanted"
1120 : "TLS output wanted");
1122 if (!(tctx->options & topt_no_body))
1124 unsigned long size = size_limit > 0 ? size_limit : ULONG_MAX;
1126 nl_check_length = abs(nl_check_length);
1127 nl_partial_match = 0;
1128 if (lseek(deliver_datafile, SPOOL_DATA_START_OFFSET, SEEK_SET) < 0)
1130 while ( (len = MIN(DELIVER_IN_BUFFER_SIZE, size)) > 0
1131 && (len = read(deliver_datafile, deliver_in_buffer, len)) > 0)
1133 if (!write_chunk(tctx, deliver_in_buffer, len))
1138 /* A read error on the body will have left len == -1 and errno set. */
1140 if (len != 0) return FALSE;
1143 /* Finished with the check string, and spool-format consideration */
1145 nl_check_length = nl_escape_length = 0;
1146 f.spool_file_wireformat = FALSE;
1148 /* If requested, add a terminating "." line (SMTP output). */
1150 if (tctx->options & topt_end_dot && !write_chunk(tctx, US".\n", 2))
1153 /* Write out any remaining data in the buffer before returning. */
1155 return (len = chunk_ptr - deliver_out_buffer) <= 0 ||
1156 transport_write_block(tctx, deliver_out_buffer, len, FALSE);
1162 /*************************************************
1163 * External interface to write the message *
1164 *************************************************/
1166 /* If there is no filtering required, call the internal function above to do
1167 the real work, passing over all the arguments from this function. Otherwise,
1168 set up a filtering process, fork another process to call the internal function
1169 to write to the filter, and in this process just suck from the filter and write
1170 down the fd in the transport context. At the end, tidy up the pipes and the
1173 Arguments: as for internal_transport_write_message() above
1175 Returns: TRUE on success; FALSE (with errno) for any failure
1176 transport_count is incremented by the number of bytes written
1180 transport_write_message(transport_ctx * tctx, int size_limit)
1182 BOOL last_filter_was_NL = TRUE;
1183 BOOL save_spool_file_wireformat = f.spool_file_wireformat;
1184 int rc, len, yield, fd_read, fd_write, save_errno;
1185 int pfd[2] = {-1, -1};
1186 pid_t filter_pid, write_pid;
1188 f.transport_filter_timed_out = FALSE;
1190 /* If there is no filter command set up, call the internal function that does
1191 the actual work, passing it the incoming fd, and return its result. */
1193 if ( !transport_filter_argv
1194 || !*transport_filter_argv
1195 || !**transport_filter_argv
1197 return internal_transport_write_message(tctx, size_limit);
1199 /* Otherwise the message must be written to a filter process and read back
1200 before being written to the incoming fd. First set up the special processing to
1201 be done during the copying. */
1203 nl_partial_match = -1;
1205 if (tctx->check_string && tctx->escape_string)
1207 nl_check = tctx->check_string;
1208 nl_check_length = Ustrlen(nl_check);
1209 nl_escape = tctx->escape_string;
1210 nl_escape_length = Ustrlen(nl_escape);
1212 else nl_check_length = nl_escape_length = 0;
1214 /* Start up a subprocess to run the command. Ensure that our main fd will
1215 be closed when the subprocess execs, but remove the flag afterwards.
1216 (Otherwise, if this is a TCP/IP socket, it can't get passed on to another
1217 process to deliver another message.) We get back stdin/stdout file descriptors.
1218 If the process creation failed, give an error return. */
1224 write_pid = (pid_t)(-1);
1227 int bits = fcntl(tctx->u.fd, F_GETFD);
1228 (void)fcntl(tctx->u.fd, F_SETFD, bits | FD_CLOEXEC);
1229 filter_pid = child_open(USS transport_filter_argv, NULL, 077,
1230 &fd_write, &fd_read, FALSE);
1231 (void)fcntl(tctx->u.fd, F_SETFD, bits & ~FD_CLOEXEC);
1233 if (filter_pid < 0) goto TIDY_UP; /* errno set */
1236 debug_printf("process %d running as transport filter: fd_write=%d fd_read=%d\n",
1237 (int)filter_pid, fd_write, fd_read);
1239 /* Fork subprocess to write the message to the filter, and return the result
1240 via a(nother) pipe. While writing to the filter, we do not do the CRLF,
1241 smtp dots, or check string processing. */
1243 if (pipe(pfd) != 0) goto TIDY_UP; /* errno set */
1244 if ((write_pid = fork()) == 0)
1247 (void)close(fd_read);
1248 (void)close(pfd[pipe_read]);
1249 nl_check_length = nl_escape_length = 0;
1251 tctx->u.fd = fd_write;
1252 tctx->check_string = tctx->escape_string = NULL;
1253 tctx->options &= ~(topt_use_crlf | topt_end_dot | topt_use_bdat);
1255 rc = internal_transport_write_message(tctx, size_limit);
1258 if ( write(pfd[pipe_write], (void *)&rc, sizeof(BOOL))
1260 || write(pfd[pipe_write], (void *)&save_errno, sizeof(int))
1262 || write(pfd[pipe_write], (void *)&tctx->addr->more_errno, sizeof(int))
1264 || write(pfd[pipe_write], (void *)&tctx->addr->delivery_time, sizeof(struct timeval))
1265 != sizeof(struct timeval)
1267 rc = FALSE; /* compiler quietening */
1268 exim_underbar_exit(0);
1272 /* Parent process: close our copy of the writing subprocess' pipes. */
1274 (void)close(pfd[pipe_write]);
1275 (void)close(fd_write);
1278 /* Writing process creation failed */
1282 errno = save_errno; /* restore */
1286 /* When testing, let the subprocess get going */
1288 testharness_pause_ms(250);
1291 debug_printf("process %d writing to transport filter\n", (int)write_pid);
1293 /* Copy the message from the filter to the output fd. A read error leaves len
1294 == -1 and errno set. We need to apply a timeout to the read, to cope with
1295 the case when the filter gets stuck, but it can be quite a long one. The
1296 default is 5m, but this is now configurable. */
1298 DEBUG(D_transport) debug_printf("copying from the filter\n");
1300 /* Copy the output of the filter, remembering if the last character was NL. If
1301 no data is returned, that counts as "ended with NL" (default setting of the
1302 variable is TRUE). The output should always be unix-format as we converted
1303 any wireformat source on writing input to the filter. */
1305 f.spool_file_wireformat = FALSE;
1306 chunk_ptr = deliver_out_buffer;
1310 sigalrm_seen = FALSE;
1311 ALARM(transport_filter_timeout);
1312 len = read(fd_read, deliver_in_buffer, DELIVER_IN_BUFFER_SIZE);
1317 f.transport_filter_timed_out = TRUE;
1321 /* If the read was successful, write the block down the original fd,
1322 remembering whether it ends in \n or not. */
1326 if (!write_chunk(tctx, deliver_in_buffer, len)) goto TIDY_UP;
1327 last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
1330 /* Otherwise, break the loop. If we have hit EOF, set yield = TRUE. */
1334 if (len == 0) yield = TRUE;
1339 /* Tidying up code. If yield = FALSE there has been an error and errno is set
1340 to something. Ensure the pipes are all closed and the processes are removed. If
1341 there has been an error, kill the processes before waiting for them, just to be
1342 sure. Also apply a paranoia timeout. */
1345 f.spool_file_wireformat = save_spool_file_wireformat;
1348 (void)close(fd_read);
1349 if (fd_write > 0) (void)close(fd_write);
1353 if (filter_pid > 0) kill(filter_pid, SIGKILL);
1354 if (write_pid > 0) kill(write_pid, SIGKILL);
1357 /* Wait for the filter process to complete. */
1359 DEBUG(D_transport) debug_printf("waiting for filter process\n");
1360 if (filter_pid > 0 && (rc = child_close(filter_pid, 30)) != 0 && yield)
1363 save_errno = ERRNO_FILTER_FAIL;
1364 tctx->addr->more_errno = rc;
1365 DEBUG(D_transport) debug_printf("filter process returned %d\n", rc);
1368 /* Wait for the writing process to complete. If it ends successfully,
1369 read the results from its pipe, provided we haven't already had a filter
1372 DEBUG(D_transport) debug_printf("waiting for writing process\n");
1375 rc = child_close(write_pid, 30);
1380 if (read(pfd[pipe_read], (void *)&ok, sizeof(BOOL)) != sizeof(BOOL))
1383 debug_printf("pipe read from writing process: %s\n", strerror(errno));
1384 save_errno = ERRNO_FILTER_FAIL;
1389 int dummy = read(pfd[pipe_read], (void *)&save_errno, sizeof(int));
1390 dummy = read(pfd[pipe_read], (void *)&tctx->addr->more_errno, sizeof(int));
1391 dummy = read(pfd[pipe_read], (void *)&tctx->addr->delivery_time, sizeof(struct timeval));
1392 dummy = dummy; /* compiler quietening */
1399 save_errno = ERRNO_FILTER_FAIL;
1400 tctx->addr->more_errno = rc;
1401 DEBUG(D_transport) debug_printf("writing process returned %d\n", rc);
1404 (void)close(pfd[pipe_read]);
1406 /* If there have been no problems we can now add the terminating "." if this is
1407 SMTP output, turning off escaping beforehand. If the last character from the
1408 filter was not NL, insert a NL to make the SMTP protocol work. */
1412 nl_check_length = nl_escape_length = 0;
1413 f.spool_file_wireformat = FALSE;
1414 if ( tctx->options & topt_end_dot
1415 && ( last_filter_was_NL
1416 ? !write_chunk(tctx, US".\n", 2)
1417 : !write_chunk(tctx, US"\n.\n", 3)
1421 /* Write out any remaining data in the buffer. */
1424 yield = (len = chunk_ptr - deliver_out_buffer) <= 0
1425 || transport_write_block(tctx, deliver_out_buffer, len, FALSE);
1428 errno = save_errno; /* From some earlier error */
1432 debug_printf("end of filtering transport writing: yield=%d\n", yield);
1434 debug_printf("errno=%d more_errno=%d\n", errno, tctx->addr->more_errno);
1444 /*************************************************
1445 * Update waiting database *
1446 *************************************************/
1448 /* This is called when an address is deferred by remote transports that are
1449 capable of sending more than one message over one connection. A database is
1450 maintained for each transport, keeping track of which messages are waiting for
1451 which hosts. The transport can then consult this when eventually a successful
1452 delivery happens, and if it finds that another message is waiting for the same
1453 host, it can fire up a new process to deal with it using the same connection.
1455 The database records are keyed by host name. They can get full if there are
1456 lots of messages waiting, and so there is a continuation mechanism for them.
1458 Each record contains a list of message ids, packed end to end without any
1459 zeros. Each one is MESSAGE_ID_LENGTH bytes long. The count field says how many
1460 in this record, and the sequence field says if there are any other records for
1461 this host. If the sequence field is 0, there are none. If it is 1, then another
1462 record with the name <hostname>:0 exists; if it is 2, then two other records
1463 with sequence numbers 0 and 1 exist, and so on.
1465 Currently, an exhaustive search of all continuation records has to be done to
1466 determine whether to add a message id to a given record. This shouldn't be
1467 too bad except in extreme cases. I can't figure out a *simple* way of doing
1470 Old records should eventually get swept up by the exim_tidydb utility.
1473 hostlist list of hosts that this message could be sent to
1474 tpname name of the transport
1480 transport_update_waiting(host_item *hostlist, uschar *tpname)
1482 const uschar *prevname = US"";
1486 DEBUG(D_transport) debug_printf("updating wait-%s database\n", tpname);
1488 /* Open the database for this transport */
1490 if (!(dbm_file = dbfn_open(string_sprintf("wait-%.200s", tpname),
1491 O_RDWR, &dbblock, TRUE, TRUE)))
1494 /* Scan the list of hosts for which this message is waiting, and ensure
1495 that the message id is in each host record. */
1497 for (host_item * host = hostlist; host; host = host->next)
1499 BOOL already = FALSE;
1500 dbdata_wait *host_record;
1504 /* Skip if this is the same host as we just processed; otherwise remember
1505 the name for next time. */
1507 if (Ustrcmp(prevname, host->name) == 0) continue;
1508 prevname = host->name;
1510 /* Look up the host record; if there isn't one, make an empty one. */
1512 if (!(host_record = dbfn_read(dbm_file, host->name)))
1514 host_record = store_get(sizeof(dbdata_wait) + MESSAGE_ID_LENGTH, FALSE);
1515 host_record->count = host_record->sequence = 0;
1518 /* Compute the current length */
1520 host_length = host_record->count * MESSAGE_ID_LENGTH;
1522 /* Search the record to see if the current message is already in it. */
1524 for (uschar * s = host_record->text; s < host_record->text + host_length;
1525 s += MESSAGE_ID_LENGTH)
1526 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1527 { already = TRUE; break; }
1529 /* If we haven't found this message in the main record, search any
1530 continuation records that exist. */
1532 for (int i = host_record->sequence - 1; i >= 0 && !already; i--)
1535 sprintf(CS buffer, "%.200s:%d", host->name, i);
1536 if ((cont = dbfn_read(dbm_file, buffer)))
1538 int clen = cont->count * MESSAGE_ID_LENGTH;
1539 for (uschar * s = cont->text; s < cont->text + clen; s += MESSAGE_ID_LENGTH)
1540 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1541 { already = TRUE; break; }
1545 /* If this message is already in a record, no need to update. */
1549 DEBUG(D_transport) debug_printf("already listed for %s\n", host->name);
1554 /* If this record is full, write it out with a new name constructed
1555 from the sequence number, increase the sequence number, and empty
1558 if (host_record->count >= WAIT_NAME_MAX)
1560 sprintf(CS buffer, "%.200s:%d", host->name, host_record->sequence);
1561 dbfn_write(dbm_file, buffer, host_record, sizeof(dbdata_wait) + host_length);
1562 host_record->sequence++;
1563 host_record->count = 0;
1567 /* If this record is not full, increase the size of the record to
1568 allow for one new message id. */
1573 store_get(sizeof(dbdata_wait) + host_length + MESSAGE_ID_LENGTH, FALSE);
1574 memcpy(newr, host_record, sizeof(dbdata_wait) + host_length);
1578 /* Now add the new name on the end */
1580 memcpy(host_record->text + host_length, message_id, MESSAGE_ID_LENGTH);
1581 host_record->count++;
1582 host_length += MESSAGE_ID_LENGTH;
1584 /* Update the database */
1586 dbfn_write(dbm_file, host->name, host_record, sizeof(dbdata_wait) + host_length);
1587 DEBUG(D_transport) debug_printf("added to list for %s\n", host->name);
1592 dbfn_close(dbm_file);
1598 /*************************************************
1599 * Test for waiting messages *
1600 *************************************************/
1602 /* This function is called by a remote transport which uses the previous
1603 function to remember which messages are waiting for which remote hosts. It's
1604 called after a successful delivery and its job is to check whether there is
1605 another message waiting for the same host. However, it doesn't do this if the
1606 current continue sequence is greater than the maximum supplied as an argument,
1607 or greater than the global connection_max_messages, which, if set, overrides.
1610 transport_name name of the transport
1611 hostname name of the host
1612 local_message_max maximum number of messages down one connection
1613 as set by the caller transport
1614 new_message_id set to the message id of a waiting message
1615 more set TRUE if there are yet more messages waiting
1616 oicf_func function to call to validate if it is ok to send
1617 to this message_id from the current instance.
1618 oicf_data opaque data for oicf_func
1620 Returns: TRUE if new_message_id set; FALSE otherwise
1623 typedef struct msgq_s
1625 uschar message_id [MESSAGE_ID_LENGTH + 1];
1630 transport_check_waiting(const uschar *transport_name, const uschar *hostname,
1631 int local_message_max, uschar *new_message_id, BOOL *more, oicf oicf_func, void *oicf_data)
1633 dbdata_wait *host_record;
1639 struct stat statbuf;
1645 debug_printf("transport_check_waiting entered\n");
1646 debug_printf(" sequence=%d local_max=%d global_max=%d\n",
1647 continue_sequence, local_message_max, connection_max_messages);
1650 /* Do nothing if we have hit the maximum number that can be send down one
1653 if (connection_max_messages >= 0) local_message_max = connection_max_messages;
1654 if (local_message_max > 0 && continue_sequence >= local_message_max)
1657 debug_printf("max messages for one connection reached: returning\n");
1661 /* Open the waiting information database. */
1663 if (!(dbm_file = dbfn_open(string_sprintf("wait-%.200s", transport_name),
1664 O_RDWR, &dbblock, TRUE, TRUE)))
1667 /* See if there is a record for this host; if not, there's nothing to do. */
1669 if (!(host_record = dbfn_read(dbm_file, hostname)))
1671 dbfn_close(dbm_file);
1672 DEBUG(D_transport) debug_printf("no messages waiting for %s\n", hostname);
1676 /* If the data in the record looks corrupt, just log something and
1677 don't try to use it. */
1679 if (host_record->count > WAIT_NAME_MAX)
1681 dbfn_close(dbm_file);
1682 log_write(0, LOG_MAIN|LOG_PANIC, "smtp-wait database entry for %s has bad "
1683 "count=%d (max=%d)", hostname, host_record->count, WAIT_NAME_MAX);
1687 /* Scan the message ids in the record from the end towards the beginning,
1688 until one is found for which a spool file actually exists. If the record gets
1689 emptied, delete it and continue with any continuation records that may exist.
1692 /* For Bug 1141, I refactored this major portion of the routine, it is risky
1693 but the 1 off will remain without it. This code now allows me to SKIP over
1694 a message I do not want to send out on this run. */
1696 host_length = host_record->count * MESSAGE_ID_LENGTH;
1702 int msgq_actual = 0;
1703 BOOL bFound = FALSE;
1704 BOOL bContinuation = FALSE;
1706 /* create an array to read entire message queue into memory for processing */
1708 msgq = store_get(sizeof(msgq_t) * host_record->count, FALSE);
1709 msgq_count = host_record->count;
1710 msgq_actual = msgq_count;
1712 for (i = 0; i < host_record->count; ++i)
1714 msgq[i].bKeep = TRUE;
1716 Ustrncpy_nt(msgq[i].message_id, host_record->text + (i * MESSAGE_ID_LENGTH),
1718 msgq[i].message_id[MESSAGE_ID_LENGTH] = 0;
1721 /* first thing remove current message id if it exists */
1723 for (i = 0; i < msgq_count; ++i)
1724 if (Ustrcmp(msgq[i].message_id, message_id) == 0)
1726 msgq[i].bKeep = FALSE;
1730 /* now find the next acceptable message_id */
1732 for (i = msgq_count - 1; i >= 0; --i) if (msgq[i].bKeep)
1735 uschar * mid = msgq[i].message_id;
1737 set_subdir_str(subdir, mid, 0);
1738 if (Ustat(spool_fname(US"input", subdir, mid, US"-D"), &statbuf) != 0)
1739 msgq[i].bKeep = FALSE;
1740 else if (!oicf_func || oicf_func(mid, oicf_data))
1742 Ustrcpy_nt(new_message_id, mid);
1743 msgq[i].bKeep = FALSE;
1750 for (msgq_actual = 0, i = 0; i < msgq_count; ++i)
1754 /* reassemble the host record, based on removed message ids, from in
1757 if (msgq_actual <= 0)
1760 host_record->count = 0;
1764 host_length = msgq_actual * MESSAGE_ID_LENGTH;
1765 host_record->count = msgq_actual;
1767 if (msgq_actual < msgq_count)
1770 for (new_count = 0, i = 0; i < msgq_count; ++i)
1772 Ustrncpy(&host_record->text[new_count++ * MESSAGE_ID_LENGTH],
1773 msgq[i].message_id, MESSAGE_ID_LENGTH);
1775 host_record->text[new_count * MESSAGE_ID_LENGTH] = 0;
1779 /* Check for a continuation record. */
1781 while (host_length <= 0)
1783 dbdata_wait * newr = NULL;
1786 /* Search for a continuation */
1788 for (int i = host_record->sequence - 1; i >= 0 && !newr; i--)
1790 sprintf(CS buffer, "%.200s:%d", hostname, i);
1791 newr = dbfn_read(dbm_file, buffer);
1794 /* If no continuation, delete the current and break the loop */
1798 dbfn_delete(dbm_file, hostname);
1802 /* Else replace the current with the continuation */
1804 dbfn_delete(dbm_file, buffer);
1806 host_length = host_record->count * MESSAGE_ID_LENGTH;
1808 bContinuation = TRUE;
1811 if (bFound) /* Usual exit from main loop */
1814 /* If host_length <= 0 we have emptied a record and not found a good message,
1815 and there are no continuation records. Otherwise there is a continuation
1816 record to process. */
1818 if (host_length <= 0)
1820 dbfn_close(dbm_file);
1821 DEBUG(D_transport) debug_printf("waiting messages already delivered\n");
1825 /* we were not able to find an acceptable message, nor was there a
1826 * continuation record. So bug out, outer logic will clean this up.
1831 Ustrcpy(new_message_id, message_id);
1832 dbfn_close(dbm_file);
1835 } /* we need to process a continuation record */
1837 /* Control gets here when an existing message has been encountered; its
1838 id is in new_message_id, and host_length is the revised length of the
1839 host record. If it is zero, the record has been removed. Update the
1840 record if required, close the database, and return TRUE. */
1842 if (host_length > 0)
1844 host_record->count = host_length/MESSAGE_ID_LENGTH;
1846 dbfn_write(dbm_file, hostname, host_record, (int)sizeof(dbdata_wait) + host_length);
1850 dbfn_close(dbm_file);
1854 /*************************************************
1855 * Deliver waiting message down same socket *
1856 *************************************************/
1858 /* Just the regain-root-privilege exec portion */
1860 transport_do_pass_socket(const uschar *transport_name, const uschar *hostname,
1861 const uschar *hostaddress, uschar *id, int socket_fd)
1864 const uschar **argv;
1866 /* Set up the calling arguments; use the standard function for the basics,
1867 but we have a number of extras that may be added. */
1869 argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, &i, FALSE, 0);
1871 if (f.smtp_authenticated) argv[i++] = US"-MCA";
1872 if (smtp_peer_options & OPTION_CHUNKING) argv[i++] = US"-MCK";
1873 if (smtp_peer_options & OPTION_DSN) argv[i++] = US"-MCD";
1874 if (smtp_peer_options & OPTION_PIPE) argv[i++] = US"-MCP";
1875 if (smtp_peer_options & OPTION_SIZE) argv[i++] = US"-MCS";
1877 if (smtp_peer_options & OPTION_TLS)
1878 if (tls_out.active.sock >= 0 || continue_proxy_cipher)
1880 argv[i++] = US"-MCt";
1881 argv[i++] = sending_ip_address;
1882 argv[i++] = string_sprintf("%d", sending_port);
1883 argv[i++] = tls_out.active.sock >= 0 ? tls_out.cipher : continue_proxy_cipher;
1886 argv[i++] = US"-MCT";
1889 if (queue_run_pid != (pid_t)0)
1891 argv[i++] = US"-MCQ";
1892 argv[i++] = string_sprintf("%d", queue_run_pid);
1893 argv[i++] = string_sprintf("%d", queue_run_pipe);
1896 argv[i++] = US"-MC";
1897 argv[i++] = US transport_name;
1898 argv[i++] = US hostname;
1899 argv[i++] = US hostaddress;
1900 argv[i++] = string_sprintf("%d", continue_sequence + 1);
1904 /* Arrange for the channel to be on stdin. */
1908 (void)dup2(socket_fd, 0);
1909 (void)close(socket_fd);
1912 DEBUG(D_exec) debug_print_argv(argv);
1913 exim_nullstd(); /* Ensure std{out,err} exist */
1914 execv(CS argv[0], (char *const *)argv);
1916 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
1917 _exit(errno); /* Note: must be _exit(), NOT exit() */
1922 /* Fork a new exim process to deliver the message, and do a re-exec, both to
1923 get a clean delivery process, and to regain root privilege in cases where it
1924 has been given away.
1927 transport_name to pass to the new process
1930 id the new message to process
1931 socket_fd the connected socket
1933 Returns: FALSE if fork fails; TRUE otherwise
1937 transport_pass_socket(const uschar *transport_name, const uschar *hostname,
1938 const uschar *hostaddress, uschar *id, int socket_fd)
1943 DEBUG(D_transport) debug_printf("transport_pass_socket entered\n");
1945 if ((pid = fork()) == 0)
1947 /* Disconnect entirely from the parent process. If we are running in the
1948 test harness, wait for a bit to allow the previous process time to finish,
1949 write the log, etc., so that the output is always in the same order for
1950 automatic comparison. */
1952 if ((pid = fork()) != 0)
1954 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded (final-pid %d)\n", pid);
1955 _exit(EXIT_SUCCESS);
1957 testharness_pause_ms(1000);
1959 transport_do_pass_socket(transport_name, hostname, hostaddress,
1963 /* If the process creation succeeded, wait for the first-level child, which
1964 immediately exits, leaving the second level process entirely disconnected from
1970 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
1971 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded (inter-pid %d)\n", pid);
1976 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
1984 /*************************************************
1985 * Set up direct (non-shell) command *
1986 *************************************************/
1988 /* This function is called when a command line is to be parsed and executed
1989 directly, without the use of /bin/sh. It is called by the pipe transport,
1990 the queryprogram router, and also from the main delivery code when setting up a
1991 transport filter process. The code for ETRN also makes use of this; in that
1992 case, no addresses are passed.
1995 argvptr pointer to anchor for argv vector
1996 cmd points to the command string (modified IN PLACE)
1997 expand_arguments true if expansion is to occur
1998 expand_failed error value to set if expansion fails; not relevant if
2000 addr chain of addresses, or NULL
2001 etext text for use in error messages
2002 errptr where to put error message if addr is NULL;
2003 otherwise it is put in the first address
2005 Returns: TRUE if all went well; otherwise an error will be
2006 set in the first address and FALSE returned
2010 transport_set_up_command(const uschar ***argvptr, uschar *cmd,
2011 BOOL expand_arguments, int expand_failed, address_item *addr,
2012 uschar *etext, uschar **errptr)
2014 const uschar **argv;
2016 int address_count = 0;
2020 /* Get store in which to build an argument list. Count the number of addresses
2021 supplied, and allow for that many arguments, plus an additional 60, which
2022 should be enough for anybody. Multiple addresses happen only when the local
2023 delivery batch option is set. */
2025 for (address_item * ad = addr; ad; ad = ad->next) address_count++;
2026 max_args = address_count + 60;
2027 *argvptr = argv = store_get((max_args+1)*sizeof(uschar *), FALSE);
2029 /* Split the command up into arguments terminated by white space. Lose
2030 trailing space at the start and end. Double-quoted arguments can contain \\ and
2031 \" escapes and so can be handled by the standard function; single-quoted
2032 arguments are verbatim. Copy each argument into a new string. */
2035 while (isspace(*s)) s++;
2037 for (; *s != 0 && argcount < max_args; argcount++)
2042 while (*ss != 0 && *ss != '\'') ss++;
2043 argv[argcount] = ss = store_get(ss - s++, is_tainted(cmd));
2044 while (*s != 0 && *s != '\'') *ss++ = *s++;
2049 argv[argcount] = string_dequote(CUSS &s);
2050 while (isspace(*s)) s++;
2053 argv[argcount] = US 0;
2055 /* If *s != 0 we have run out of argument slots. */
2059 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
2063 addr->transport_return = FAIL;
2064 addr->message = msg;
2070 /* Expand each individual argument if required. Expansion happens for pipes set
2071 up in filter files and with directly-supplied commands. It does not happen if
2072 the pipe comes from a traditional .forward file. A failing expansion is a big
2073 disaster if the command came from Exim's configuration; if it came from a user
2074 it is just a normal failure. The expand_failed value is used as the error value
2075 to cater for these two cases.
2077 An argument consisting just of the text "$pipe_addresses" is treated specially.
2078 It is not passed to the general expansion function. Instead, it is replaced by
2079 a number of arguments, one for each address. This avoids problems with shell
2080 metacharacters and spaces in addresses.
2082 If the parent of the top address has an original part of "system-filter", this
2083 pipe was set up by the system filter, and we can permit the expansion of
2088 debug_printf("direct command:\n");
2089 for (int i = 0; argv[i]; i++)
2090 debug_printf(" argv[%d] = '%s'\n", i, string_printing(argv[i]));
2093 if (expand_arguments)
2095 BOOL allow_dollar_recipients = addr != NULL &&
2096 addr->parent != NULL &&
2097 Ustrcmp(addr->parent->address, "system-filter") == 0;
2099 for (int i = 0; argv[i] != US 0; i++)
2102 /* Handle special fudge for passing an address list */
2105 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
2106 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
2110 if (argcount + address_count - 1 > max_args)
2112 addr->transport_return = FAIL;
2113 addr->message = string_sprintf("Too many arguments to command \"%s\" "
2114 "in %s", cmd, etext);
2118 additional = address_count - 1;
2120 memmove(argv + i + 1 + additional, argv + i + 1,
2121 (argcount - i)*sizeof(uschar *));
2123 for (address_item * ad = addr; ad; ad = ad->next)
2125 argv[i++] = ad->address;
2129 /* Subtract one since we replace $pipe_addresses */
2134 /* Handle special case of $address_pipe when af_force_command is set */
2136 else if (addr != NULL && testflag(addr,af_force_command) &&
2137 (Ustrcmp(argv[i], "$address_pipe") == 0 ||
2138 Ustrcmp(argv[i], "${address_pipe}") == 0))
2140 int address_pipe_argcount = 0;
2141 int address_pipe_max_args;
2142 uschar **address_pipe_argv;
2145 /* We can never have more then the argv we will be loading into */
2146 address_pipe_max_args = max_args - argcount + 1;
2149 debug_printf("address_pipe_max_args=%d\n", address_pipe_max_args);
2151 /* We allocate an additional for (uschar *)0 */
2152 address_pipe_argv = store_get((address_pipe_max_args+1)*sizeof(uschar *), FALSE);
2154 /* +1 because addr->local_part[0] == '|' since af_force_command is set */
2155 s = expand_string(addr->local_part + 1);
2156 tainted = is_tainted(s);
2158 if (s == NULL || *s == '\0')
2160 addr->transport_return = FAIL;
2161 addr->message = string_sprintf("Expansion of \"%s\" "
2162 "from command \"%s\" in %s failed: %s",
2163 (addr->local_part + 1), cmd, etext, expand_string_message);
2167 while (isspace(*s)) s++; /* strip leading space */
2169 while (*s != 0 && address_pipe_argcount < address_pipe_max_args)
2174 while (*ss != 0 && *ss != '\'') ss++;
2175 address_pipe_argv[address_pipe_argcount++] = ss = store_get(ss - s++, tainted);
2176 while (*s != 0 && *s != '\'') *ss++ = *s++;
2180 else address_pipe_argv[address_pipe_argcount++] =
2181 string_copy(string_dequote(CUSS &s));
2182 while (isspace(*s)) s++; /* strip space after arg */
2185 address_pipe_argv[address_pipe_argcount] = US 0;
2187 /* If *s != 0 we have run out of argument slots. */
2190 uschar *msg = string_sprintf("Too many arguments in $address_pipe "
2191 "\"%s\" in %s", addr->local_part + 1, etext);
2194 addr->transport_return = FAIL;
2195 addr->message = msg;
2201 /* address_pipe_argcount - 1
2202 * because we are replacing $address_pipe in the argument list
2203 * with the first thing it expands to */
2204 if (argcount + address_pipe_argcount - 1 > max_args)
2206 addr->transport_return = FAIL;
2207 addr->message = string_sprintf("Too many arguments to command "
2208 "\"%s\" after expanding $address_pipe in %s", cmd, etext);
2212 /* If we are not just able to replace the slot that contained
2213 * $address_pipe (address_pipe_argcount == 1)
2214 * We have to move the existing argv by address_pipe_argcount - 1
2215 * Visually if address_pipe_argcount == 2:
2216 * [argv 0][argv 1][argv 2($address_pipe)][argv 3][0]
2217 * [argv 0][argv 1][ap_arg0][ap_arg1][old argv 3][0]
2219 if (address_pipe_argcount > 1)
2221 /* current position + additional args */
2222 argv + i + address_pipe_argcount,
2223 /* current position + 1 (for the (uschar *)0 at the end) */
2225 /* -1 for the (uschar *)0 at the end)*/
2226 (argcount - i)*sizeof(uschar *)
2229 /* Now we fill in the slots we just moved argv out of
2230 * [argv 0][argv 1][argv 2=pipeargv[0]][argv 3=pipeargv[1]][old argv 3][0]
2232 for (int address_pipe_i = 0;
2233 address_pipe_argv[address_pipe_i] != US 0;
2236 argv[i++] = address_pipe_argv[address_pipe_i];
2240 /* Subtract one since we replace $address_pipe */
2245 /* Handle normal expansion string */
2249 const uschar *expanded_arg;
2250 f.enable_dollar_recipients = allow_dollar_recipients;
2251 expanded_arg = expand_cstring(argv[i]);
2252 f.enable_dollar_recipients = FALSE;
2256 uschar *msg = string_sprintf("Expansion of \"%s\" "
2257 "from command \"%s\" in %s failed: %s",
2258 argv[i], cmd, etext, expand_string_message);
2261 addr->transport_return = expand_failed;
2262 addr->message = msg;
2267 argv[i] = expanded_arg;
2273 debug_printf("direct command after expansion:\n");
2274 for (int i = 0; argv[i] != US 0; i++)
2275 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2282 #endif /*!MACRO_PREDEF*/
2285 /* End of transport.c */