1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
6 /* See the file NOTICE for conditions of use and distribution. */
8 /* General functions concerned with transportation, and generic options for all
14 #ifdef HAVE_LINUX_SENDFILE
15 #include <sys/sendfile.h>
18 /* Structure for keeping list of addresses that have been added to
19 Envelope-To:, in order to avoid duplication. */
27 /* Static data for write_chunk() */
29 static uschar *chunk_ptr; /* chunk pointer */
30 static uschar *nl_check; /* string to look for at line start */
31 static int nl_check_length; /* length of same */
32 static uschar *nl_escape; /* string to insert */
33 static int nl_escape_length; /* length of same */
34 static int nl_partial_match; /* length matched at chunk end */
37 /* Generic options for transports, all of which live inside transport_instance
38 data blocks and which therefore have the opt_public flag set. Note that there
39 are other options living inside this structure which can be set only from
40 certain transports. */
42 optionlist optionlist_transports[] = {
43 { "*expand_group", opt_stringptr|opt_hidden|opt_public,
44 (void *)offsetof(transport_instance, expand_gid) },
45 { "*expand_user", opt_stringptr|opt_hidden|opt_public,
46 (void *)offsetof(transport_instance, expand_uid) },
47 { "*headers_rewrite_flags", opt_int|opt_public|opt_hidden,
48 (void *)offsetof(transport_instance, rewrite_existflags) },
49 { "*headers_rewrite_rules", opt_void|opt_public|opt_hidden,
50 (void *)offsetof(transport_instance, rewrite_rules) },
51 { "*set_group", opt_bool|opt_hidden|opt_public,
52 (void *)offsetof(transport_instance, gid_set) },
53 { "*set_user", opt_bool|opt_hidden|opt_public,
54 (void *)offsetof(transport_instance, uid_set) },
55 { "body_only", opt_bool|opt_public,
56 (void *)offsetof(transport_instance, body_only) },
57 { "current_directory", opt_stringptr|opt_public,
58 (void *)offsetof(transport_instance, current_dir) },
59 { "debug_print", opt_stringptr | opt_public,
60 (void *)offsetof(transport_instance, debug_string) },
61 { "delivery_date_add", opt_bool|opt_public,
62 (void *)(offsetof(transport_instance, delivery_date_add)) },
63 { "disable_logging", opt_bool|opt_public,
64 (void *)(offsetof(transport_instance, disable_logging)) },
65 { "driver", opt_stringptr|opt_public,
66 (void *)offsetof(transport_instance, driver_name) },
67 { "envelope_to_add", opt_bool|opt_public,
68 (void *)(offsetof(transport_instance, envelope_to_add)) },
70 { "event_action", opt_stringptr | opt_public,
71 (void *)offsetof(transport_instance, event_action) },
73 { "group", opt_expand_gid|opt_public,
74 (void *)offsetof(transport_instance, gid) },
75 { "headers_add", opt_stringptr|opt_public|opt_rep_str,
76 (void *)offsetof(transport_instance, add_headers) },
77 { "headers_only", opt_bool|opt_public,
78 (void *)offsetof(transport_instance, headers_only) },
79 { "headers_remove", opt_stringptr|opt_public|opt_rep_str,
80 (void *)offsetof(transport_instance, remove_headers) },
81 { "headers_rewrite", opt_rewrite|opt_public,
82 (void *)offsetof(transport_instance, headers_rewrite) },
83 { "home_directory", opt_stringptr|opt_public,
84 (void *)offsetof(transport_instance, home_dir) },
85 { "initgroups", opt_bool|opt_public,
86 (void *)offsetof(transport_instance, initgroups) },
87 { "max_parallel", opt_stringptr|opt_public,
88 (void *)offsetof(transport_instance, max_parallel) },
89 { "message_size_limit", opt_stringptr|opt_public,
90 (void *)offsetof(transport_instance, message_size_limit) },
91 { "rcpt_include_affixes", opt_bool|opt_public,
92 (void *)offsetof(transport_instance, rcpt_include_affixes) },
93 { "retry_use_local_part", opt_bool|opt_public,
94 (void *)offsetof(transport_instance, retry_use_local_part) },
95 { "return_path", opt_stringptr|opt_public,
96 (void *)(offsetof(transport_instance, return_path)) },
97 { "return_path_add", opt_bool|opt_public,
98 (void *)(offsetof(transport_instance, return_path_add)) },
99 { "shadow_condition", opt_stringptr|opt_public,
100 (void *)offsetof(transport_instance, shadow_condition) },
101 { "shadow_transport", opt_stringptr|opt_public,
102 (void *)offsetof(transport_instance, shadow) },
103 { "transport_filter", opt_stringptr|opt_public,
104 (void *)offsetof(transport_instance, filter_command) },
105 { "transport_filter_timeout", opt_time|opt_public,
106 (void *)offsetof(transport_instance, filter_timeout) },
107 { "user", opt_expand_uid|opt_public,
108 (void *)offsetof(transport_instance, uid) }
111 int optionlist_transports_size =
112 sizeof(optionlist_transports)/sizeof(optionlist);
115 /*************************************************
116 * Initialize transport list *
117 *************************************************/
119 /* Read the transports section of the configuration file, and set up a chain of
120 transport instances according to its contents. Each transport has generic
121 options and may also have its own private options. This function is only ever
122 called when transports == NULL. We use generic code in readconf to do most of
128 transport_instance *t;
130 readconf_driver_init(US"transport",
131 (driver_instance **)(&transports), /* chain anchor */
132 (driver_info *)transports_available, /* available drivers */
133 sizeof(transport_info), /* size of info block */
134 &transport_defaults, /* default values for generic options */
135 sizeof(transport_instance), /* size of instance block */
136 optionlist_transports, /* generic options */
137 optionlist_transports_size);
139 /* Now scan the configured transports and check inconsistencies. A shadow
140 transport is permitted only for local transports. */
142 for (t = transports; t != NULL; t = t->next)
146 if (t->shadow != NULL)
147 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
148 "shadow transport not allowed on non-local transport %s", t->name);
151 if (t->body_only && t->headers_only)
152 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
153 "%s transport: body_only and headers_only are mutually exclusive",
160 /*************************************************
161 * Write block of data *
162 *************************************************/
164 /* Subroutine called by write_chunk() and at the end of the message actually
165 to write a data block. Also called directly by some transports to write
166 additional data to the file descriptor (e.g. prefix, suffix).
168 If a transport wants data transfers to be timed, it sets a non-zero value in
169 transport_write_timeout. A non-zero transport_write_timeout causes a timer to
170 be set for each block of data written from here. If time runs out, then write()
171 fails and provokes an error return. The caller can then inspect sigalrm_seen to
174 On some systems, if a quota is exceeded during the write, the yield is the
175 number of bytes written rather than an immediate error code. This also happens
176 on some systems in other cases, for example a pipe that goes away because the
177 other end's process terminates (Linux). On other systems, (e.g. Solaris 2) you
178 get the error codes the first time.
180 The write() function is also interruptible; the Solaris 2.6 man page says:
182 If write() is interrupted by a signal before it writes any
183 data, it will return -1 with errno set to EINTR.
185 If write() is interrupted by a signal after it successfully
186 writes some data, it will return the number of bytes written.
188 To handle these cases, we want to restart the write() to output the remainder
189 of the data after a non-negative return from write(), except after a timeout.
190 In the error cases (EDQUOT, EPIPE) no bytes get written the second time, and a
191 proper error then occurs. In principle, after an interruption, the second
192 write() could suffer the same fate, but we do not want to continue for
193 evermore, so stick a maximum repetition count on the loop to act as a
197 fd file descriptor to write to
198 block block of bytes to write
199 len number of bytes to write
201 Returns: TRUE on success, FALSE on failure (with errno preserved);
202 transport_count is incremented by the number of bytes written
206 transport_write_block(int fd, uschar *block, int len)
208 int i, rc, save_errno;
209 int local_timeout = transport_write_timeout;
211 /* This loop is for handling incomplete writes and other retries. In most
212 normal cases, it is only ever executed once. */
214 for (i = 0; i < 100; i++)
217 debug_printf("writing data block fd=%d size=%d timeout=%d\n",
218 fd, len, local_timeout);
220 /* This code makes use of alarm() in order to implement the timeout. This
221 isn't a very tidy way of doing things. Using non-blocking I/O with select()
222 provides a neater approach. However, I don't know how to do this when TLS is
225 if (transport_write_timeout <= 0) /* No timeout wanted */
228 if (tls_out.active == fd) rc = tls_write(FALSE, block, len); else
230 rc = write(fd, block, len);
234 /* Timeout wanted. */
238 alarm(local_timeout);
240 if (tls_out.active == fd)
241 rc = tls_write(FALSE, block, len);
244 rc = write(fd, block, len);
246 local_timeout = alarm(0);
254 /* Hopefully, the most common case is success, so test that first. */
256 if (rc == len) { transport_count += len; return TRUE; }
258 /* A non-negative return code is an incomplete write. Try again for the rest
259 of the block. If we have exactly hit the timeout, give up. */
265 transport_count += rc;
266 DEBUG(D_transport) debug_printf("write incomplete (%d)\n", rc);
267 goto CHECK_TIMEOUT; /* A few lines below */
270 /* A negative return code with an EINTR error is another form of
271 incomplete write, zero bytes having been written */
273 if (save_errno == EINTR)
276 debug_printf("write interrupted before anything written\n");
277 goto CHECK_TIMEOUT; /* A few lines below */
280 /* A response of EAGAIN from write() is likely only in the case of writing
281 to a FIFO that is not swallowing the data as fast as Exim is writing it. */
283 if (save_errno == EAGAIN)
286 debug_printf("write temporarily locked out, waiting 1 sec\n");
289 /* Before continuing to try another write, check that we haven't run out of
293 if (transport_write_timeout > 0 && local_timeout <= 0)
301 /* Otherwise there's been an error */
303 DEBUG(D_transport) debug_printf("writing error %d: %s\n", save_errno,
304 strerror(save_errno));
309 /* We've tried and tried and tried but still failed */
311 errno = ERRNO_WRITEINCOMPLETE;
318 /*************************************************
319 * Write formatted string *
320 *************************************************/
322 /* This is called by various transports. It is a convenience function.
327 ... arguments for format
329 Returns: the yield of transport_write_block()
333 transport_write_string(int fd, const char *format, ...)
336 va_start(ap, format);
337 if (!string_vformat(big_buffer, big_buffer_size, format, ap))
338 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong formatted string in transport");
340 return transport_write_block(fd, big_buffer, Ustrlen(big_buffer));
346 /*************************************************
347 * Write character chunk *
348 *************************************************/
350 /* Subroutine used by transport_write_message() to scan character chunks for
351 newlines and act appropriately. The object is to minimise the number of writes.
352 The output byte stream is buffered up in deliver_out_buffer, which is written
353 only when it gets full, thus minimizing write operations and TCP packets.
355 Static data is used to handle the case when the last character of the previous
356 chunk was NL, or matched part of the data that has to be escaped.
359 fd file descript to write to
360 chunk pointer to data to write
361 len length of data to write
362 tctx transport context - processing to be done during output
364 In addition, the static nl_xxx variables must be set as required.
366 Returns: TRUE on success, FALSE on failure (with errno preserved)
370 write_chunk(int fd, transport_ctx * tctx, uschar *chunk, int len)
372 uschar *start = chunk;
373 uschar *end = chunk + len;
375 int mlen = DELIVER_OUT_BUFFER_SIZE - nl_escape_length - 2;
377 /* The assumption is made that the check string will never stretch over move
378 than one chunk since the only time there are partial matches is when copying
379 the body in large buffers. There is always enough room in the buffer for an
380 escape string, since the loop below ensures this for each character it
381 processes, and it won't have stuck in the escape string if it left a partial
384 if (nl_partial_match >= 0)
386 if (nl_check_length > 0 && len >= nl_check_length &&
387 Ustrncmp(start, nl_check + nl_partial_match,
388 nl_check_length - nl_partial_match) == 0)
390 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
391 chunk_ptr += nl_escape_length;
392 start += nl_check_length - nl_partial_match;
395 /* The partial match was a false one. Insert the characters carried over
396 from the previous chunk. */
398 else if (nl_partial_match > 0)
400 Ustrncpy(chunk_ptr, nl_check, nl_partial_match);
401 chunk_ptr += nl_partial_match;
404 nl_partial_match = -1;
407 /* Now process the characters in the chunk. Whenever we hit a newline we check
408 for possible escaping. The code for the non-NL route should be as fast as
411 for (ptr = start; ptr < end; ptr++)
415 /* Flush the buffer if it has reached the threshold - we want to leave enough
416 room for the next uschar, plus a possible extra CR for an LF, plus the escape
419 if ((len = chunk_ptr - deliver_out_buffer) > mlen)
421 DEBUG(D_transport) debug_printf("flushing headers buffer\n");
423 /* If CHUNKING, prefix with BDAT (size) NON-LAST. Also, reap responses
424 from previous SMTP commands. */
426 if (tctx && tctx->options & topt_use_bdat && tctx->chunk_cb)
428 if ( tctx->chunk_cb(fd, tctx, (unsigned)len, 0) != OK
429 || !transport_write_block(fd, deliver_out_buffer, len)
430 || tctx->chunk_cb(fd, tctx, 0, tc_reap_prev) != OK
435 if (!transport_write_block(fd, deliver_out_buffer, len))
437 chunk_ptr = deliver_out_buffer;
440 if ((ch = *ptr) == '\n')
442 int left = end - ptr - 1; /* count of chars left after NL */
444 /* Insert CR before NL if required */
446 if (tctx && tctx->options & topt_use_crlf) *chunk_ptr++ = '\r';
448 transport_newlines++;
450 /* The check_string test (formerly "from hack") replaces the specific
451 string at the start of a line with an escape string (e.g. "From " becomes
452 ">From " or "." becomes "..". It is a case-sensitive test. The length
453 check above ensures there is always enough room to insert this string. */
455 if (nl_check_length > 0)
457 if (left >= nl_check_length &&
458 Ustrncmp(ptr+1, nl_check, nl_check_length) == 0)
460 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
461 chunk_ptr += nl_escape_length;
462 ptr += nl_check_length;
465 /* Handle the case when there isn't enough left to match the whole
466 check string, but there may be a partial match. We remember how many
467 characters matched, and finish processing this chunk. */
469 else if (left <= 0) nl_partial_match = 0;
471 else if (Ustrncmp(ptr+1, nl_check, left) == 0)
473 nl_partial_match = left;
479 /* Not a NL character */
481 else *chunk_ptr++ = ch;
490 /*************************************************
491 * Generate address for RCPT TO *
492 *************************************************/
494 /* This function puts together an address for RCPT to, using the caseful
495 version of the local part and the caseful version of the domain. If there is no
496 prefix or suffix, or if affixes are to be retained, we can just use the
497 original address. Otherwise, if there is a prefix but no suffix we can use a
498 pointer into the original address. If there is a suffix, however, we have to
502 addr the address item
503 include_affixes TRUE if affixes are to be included
509 transport_rcpt_address(address_item *addr, BOOL include_affixes)
516 setflag(addr, af_include_affixes); /* Affects logged => line */
517 return addr->address;
520 if (addr->suffix == NULL)
522 if (addr->prefix == NULL) return addr->address;
523 return addr->address + Ustrlen(addr->prefix);
526 at = Ustrrchr(addr->address, '@');
527 plen = (addr->prefix == NULL)? 0 : Ustrlen(addr->prefix);
528 slen = Ustrlen(addr->suffix);
530 return string_sprintf("%.*s@%s", (at - addr->address - plen - slen),
531 addr->address + plen, at + 1);
535 /*************************************************
536 * Output Envelope-To: address & scan duplicates *
537 *************************************************/
539 /* This function is called from internal_transport_write_message() below, when
540 generating an Envelope-To: header line. It checks for duplicates of the given
541 address and its ancestors. When one is found, this function calls itself
542 recursively, to output the envelope address of the duplicate.
544 We want to avoid duplication in the list, which can arise for example when
545 A->B,C and then both B and C alias to D. This can also happen when there are
546 unseen drivers in use. So a list of addresses that have been output is kept in
549 It is also possible to have loops in the address ancestry/duplication graph,
550 for example if there are two top level addresses A and B and we have A->B,C and
551 B->A. To break the loop, we use a list of processed addresses in the dlist
554 After handling duplication, this function outputs the progenitor of the given
558 p the address we are interested in
559 pplist address of anchor of the list of addresses not to output
560 pdlist address of anchor of the list of processed addresses
561 first TRUE if this is the first address; set it FALSE afterwards
562 fd the file descriptor to write to
563 tctx transport context - processing to be done during output
565 Returns: FALSE if writing failed
569 write_env_to(address_item *p, struct aci **pplist, struct aci **pdlist,
570 BOOL *first, int fd, transport_ctx * tctx)
575 /* Do nothing if we have already handled this address. If not, remember it
576 so that we don't handle it again. */
578 for (ppp = *pdlist; ppp; ppp = ppp->next) if (p == ppp->ptr) return TRUE;
580 ppp = store_get(sizeof(struct aci));
585 /* Now scan up the ancestry, checking for duplicates at each generation. */
587 for (pp = p;; pp = pp->parent)
590 for (dup = addr_duplicate; dup; dup = dup->next)
591 if (dup->dupof == pp) /* a dup of our address */
592 if (!write_env_to(dup, pplist, pdlist, first, fd, tctx))
594 if (!pp->parent) break;
597 /* Check to see if we have already output the progenitor. */
599 for (ppp = *pplist; ppp; ppp = ppp->next) if (pp == ppp->ptr) break;
600 if (ppp) return TRUE;
602 /* Remember what we have output, and output it. */
604 ppp = store_get(sizeof(struct aci));
609 if (!*first && !write_chunk(fd, tctx, US",\n ", 3)) return FALSE;
611 return write_chunk(fd, tctx, pp->address, Ustrlen(pp->address));
617 /* Add/remove/rewwrite headers, and send them plus the empty-line sparator.
623 addr (chain of) addresses (for extra headers), or NULL;
624 only the first address is used
625 fd file descriptor to write the message to
626 tctx transport context
627 sendfn function for output (transport or verify)
629 Returns: TRUE on success; FALSE on failure.
632 transport_headers_send(int fd, transport_ctx * tctx,
633 BOOL (*sendfn)(int fd, transport_ctx * tctx, uschar * s, int len))
637 transport_instance * tblock = tctx ? tctx->tblock : NULL;
638 address_item * addr = tctx ? tctx->addr : NULL;
640 /* Then the message's headers. Don't write any that are flagged as "old";
641 that means they were rewritten, or are a record of envelope rewriting, or
642 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
643 match any entries therein. It is a colon-sep list; expand the items
644 separately and squash any empty ones.
645 Then check addr->prop.remove_headers too, provided that addr is not NULL. */
647 for (h = header_list; h; h = h->next) if (h->type != htype_old)
650 BOOL include_header = TRUE;
652 list = tblock ? tblock->remove_headers : NULL;
653 for (i = 0; i < 2; i++) /* For remove_headers && addr->prop.remove_headers */
657 int sep = ':'; /* This is specified as a colon-separated list */
659 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
664 if (!(s = expand_string(s)) && !expand_string_forcedfail)
666 errno = ERRNO_CHHEADER_FAIL;
669 len = s ? Ustrlen(s) : 0;
670 if (strncmpic(h->text, s, len) != 0) continue;
672 while (*ss == ' ' || *ss == '\t') ss++;
673 if (*ss == ':') break;
675 if (s) { include_header = FALSE; break; }
677 if (addr) list = addr->prop.remove_headers;
680 /* If this header is to be output, try to rewrite it if there are rewriting
685 if (tblock && tblock->rewrite_rules)
687 void *reset_point = store_get(0);
690 if ((hh = rewrite_header(h, NULL, NULL, tblock->rewrite_rules,
691 tblock->rewrite_existflags, FALSE)))
693 if (!sendfn(fd, tctx, hh->text, hh->slen)) return FALSE;
694 store_reset(reset_point);
695 continue; /* With the next header line */
699 /* Either no rewriting rules, or it didn't get rewritten */
701 if (!sendfn(fd, tctx, h->text, h->slen)) return FALSE;
708 DEBUG(D_transport) debug_printf("removed header line:\n%s---\n", h->text);
712 /* Add on any address-specific headers. If there are multiple addresses,
713 they will all have the same headers in order to be batched. The headers
714 are chained in reverse order of adding (so several addresses from the
715 same alias might share some of them) but we want to output them in the
716 opposite order. This is a bit tedious, but there shouldn't be very many
717 of them. We just walk the list twice, reversing the pointers each time,
718 but on the second time, write out the items.
720 Headers added to an address by a router are guaranteed to end with a newline.
726 header_line *hprev = addr->prop.extra_headers;
728 for (i = 0; i < 2; i++)
729 for (h = hprev, hprev = NULL; h; h = hnext)
736 if (!sendfn(fd, tctx, h->text, h->slen)) return FALSE;
738 debug_printf("added header line(s):\n%s---\n", h->text);
743 /* If a string containing additional headers exists it is a newline-sep
744 list. Expand each item and write out the result. This is done last so that
745 if it (deliberately or accidentally) isn't in header format, it won't mess
746 up any other headers. An empty string or a forced expansion failure are
747 noops. An added header string from a transport may not end with a newline;
748 add one if it does not. */
750 if (tblock && (list = CUS tblock->add_headers))
755 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
756 if ((s = expand_string(s)))
758 int len = Ustrlen(s);
761 if (!sendfn(fd, tctx, s, len)) return FALSE;
762 if (s[len-1] != '\n' && !sendfn(fd, tctx, US"\n", 1))
766 debug_printf("added header line:\n%s", s);
767 if (s[len-1] != '\n') debug_printf("\n");
768 debug_printf("---\n");
772 else if (!expand_string_forcedfail)
773 { errno = ERRNO_CHHEADER_FAIL; return FALSE; }
776 /* Separate headers from body with a blank line */
778 return sendfn(fd, tctx, US"\n", 1);
782 /*************************************************
783 * Write the message *
784 *************************************************/
786 /* This function writes the message to the given file descriptor. The headers
787 are in the in-store data structure, and the rest of the message is in the open
788 file descriptor deliver_datafile. Make sure we start it at the beginning.
790 . If add_return_path is TRUE, a "return-path:" header is added to the message,
791 containing the envelope sender's address.
793 . If add_envelope_to is TRUE, a "envelope-to:" header is added to the message,
794 giving the top-level envelope address that caused this delivery to happen.
796 . If add_delivery_date is TRUE, a "delivery-date:" header is added to the
797 message. It gives the time and date that delivery took place.
799 . If check_string is not null, the start of each line is checked for that
800 string. If it is found, it is replaced by escape_string. This used to be
801 the "from hack" for files, and "smtp_dots" for escaping SMTP dots.
803 . If use_crlf is true, newlines are turned into CRLF (SMTP output).
805 The yield is TRUE if all went well, and FALSE if not. Exit *immediately* after
806 any writing or reading error, leaving the code in errno intact. Error exits
807 can include timeouts for certain transports, which are requested by setting
808 transport_write_timeout non-zero.
811 fd file descriptor to write the message to
813 addr (chain of) addresses (for extra headers), or NULL;
814 only the first address is used
815 tblock optional transport instance block (NULL signifies NULL/0):
816 add_headers a string containing one or more headers to add; it is
817 expanded, and must be in correct RFC 822 format as
818 it is transmitted verbatim; NULL => no additions,
819 and so does empty string or forced expansion fail
820 remove_headers a colon-separated list of headers to remove, or NULL
821 rewrite_rules chain of header rewriting rules
822 rewrite_existflags flags for the rewriting rules
823 options bit-wise options:
824 add_return_path if TRUE, add a "return-path" header
825 add_envelope_to if TRUE, add a "envelope-to" header
826 add_delivery_date if TRUE, add a "delivery-date" header
827 use_crlf if TRUE, turn NL into CR LF
828 end_dot if TRUE, send a terminating "." line at the end
829 no_headers if TRUE, omit the headers
830 no_body if TRUE, omit the body
831 check_string a string to check for at the start of lines, or NULL
832 escape_string a string to insert in front of any check string
833 size_limit if > 0, this is a limit to the size of message written;
834 it is used when returning messages to their senders,
835 and is approximate rather than exact, owing to chunk
838 Returns: TRUE on success; FALSE (with errno) on failure.
839 In addition, the global variable transport_count
840 is incremented by the number of bytes written.
844 internal_transport_write_message(int fd, transport_ctx * tctx, int size_limit)
848 /* Initialize pointer in output buffer. */
850 chunk_ptr = deliver_out_buffer;
852 /* Set up the data for start-of-line data checking and escaping */
854 nl_partial_match = -1;
855 if (tctx->check_string && tctx->escape_string)
857 nl_check = tctx->check_string;
858 nl_check_length = Ustrlen(nl_check);
859 nl_escape = tctx->escape_string;
860 nl_escape_length = Ustrlen(nl_escape);
863 nl_check_length = nl_escape_length = 0;
865 /* Whether the escaping mechanism is applied to headers or not is controlled by
866 an option (set for SMTP, not otherwise). Negate the length if not wanted till
867 after the headers. */
869 if (!(tctx->options & topt_escape_headers))
870 nl_check_length = -nl_check_length;
872 /* Write the headers if required, including any that have to be added. If there
873 are header rewriting rules, apply them. */
875 if (!(tctx->options & topt_no_headers))
877 /* Add return-path: if requested. */
879 if (tctx->options & topt_add_return_path)
881 uschar buffer[ADDRESS_MAXLENGTH + 20];
882 int n = sprintf(CS buffer, "Return-path: <%.*s>\n", ADDRESS_MAXLENGTH,
884 if (!write_chunk(fd, tctx, buffer, n)) return FALSE;
887 /* Add envelope-to: if requested */
889 if (tctx->options & topt_add_envelope_to)
893 struct aci *plist = NULL;
894 struct aci *dlist = NULL;
895 void *reset_point = store_get(0);
897 if (!write_chunk(fd, tctx, US"Envelope-to: ", 13)) return FALSE;
899 /* Pick up from all the addresses. The plist and dlist variables are
900 anchors for lists of addresses already handled; they have to be defined at
901 this level becuase write_env_to() calls itself recursively. */
903 for (p = tctx->addr; p; p = p->next)
904 if (!write_env_to(p, &plist, &dlist, &first, fd, tctx))
907 /* Add a final newline and reset the store used for tracking duplicates */
909 if (!write_chunk(fd, tctx, US"\n", 1)) return FALSE;
910 store_reset(reset_point);
913 /* Add delivery-date: if requested. */
915 if (tctx->options & topt_add_delivery_date)
918 int n = sprintf(CS buffer, "Delivery-date: %s\n", tod_stamp(tod_full));
919 if (!write_chunk(fd, tctx, buffer, n)) return FALSE;
922 /* Then the message's headers. Don't write any that are flagged as "old";
923 that means they were rewritten, or are a record of envelope rewriting, or
924 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
925 match any entries therein. Then check addr->prop.remove_headers too, provided that
928 if (!transport_headers_send(fd, tctx, &write_chunk))
932 /* When doing RFC3030 CHUNKING output, work out how much data would be in a
933 last-BDAT, consisting of the current write_chunk() output buffer fill
934 (optimally, all of the headers - but it does not matter if we already had to
935 flush that buffer with non-last BDAT prependix) plus the amount of body data
936 (as expanded for CRLF lines). Then create and write BDAT(s), and ensure
937 that further use of write_chunk() will not prepend BDATs.
938 The first BDAT written will also first flush any outstanding MAIL and RCPT
939 commands which were buffered thans to PIPELINING.
940 Commands go out (using a send()) from a different buffer to data (using a
941 write()). They might not end up in the same TCP segment, which is
944 if (tctx->options & topt_use_bdat)
949 if ((hsize = chunk_ptr - deliver_out_buffer) < 0)
951 if (!(tctx->options & topt_no_body))
953 if ((fsize = lseek(deliver_datafile, 0, SEEK_END)) < 0) return FALSE;
954 fsize -= SPOOL_DATA_START_OFFSET;
955 if (size_limit > 0 && fsize > size_limit)
957 size = hsize + fsize;
958 if (tctx->options & topt_use_crlf)
959 size += body_linecount; /* account for CRLF-expansion */
962 /* If the message is large, emit first a non-LAST chunk with just the
963 headers, and reap the command responses. This lets us error out early
964 on RCPT rejects rather than sending megabytes of data. Include headers
965 on the assumption they are cheap enough and some clever implementations
966 might errorcheck them too, on-the-fly, and reject that chunk. */
968 if (size > DELIVER_OUT_BUFFER_SIZE && hsize > 0)
971 debug_printf("sending small initial BDAT; hssize=%d\n", hsize);
972 if ( tctx->chunk_cb(fd, tctx, hsize, 0) != OK
973 || !transport_write_block(fd, deliver_out_buffer, hsize)
974 || tctx->chunk_cb(fd, tctx, 0, tc_reap_prev) != OK
977 chunk_ptr = deliver_out_buffer;
981 /* Emit a LAST datachunk command. */
983 if (tctx->chunk_cb(fd, tctx, size, tc_chunk_last) != OK)
986 tctx->options &= ~topt_use_bdat;
989 /* If the body is required, ensure that the data for check strings (formerly
990 the "from hack") is enabled by negating the length if necessary. (It will be
991 negative in cases where it isn't to apply to the headers). Then ensure the body
992 is positioned at the start of its file (following the message id), then write
993 it, applying the size limit if required. */
995 if (!(tctx->options & topt_no_body))
997 int size = size_limit;
999 nl_check_length = abs(nl_check_length);
1000 nl_partial_match = 0;
1001 if (lseek(deliver_datafile, SPOOL_DATA_START_OFFSET, SEEK_SET) < 0)
1003 while ( (len = MAX(DELIVER_IN_BUFFER_SIZE, size)) > 0
1004 && (len = read(deliver_datafile, deliver_in_buffer, len)) > 0)
1006 if (!write_chunk(fd, tctx, deliver_in_buffer, len))
1011 /* A read error on the body will have left len == -1 and errno set. */
1013 if (len != 0) return FALSE;
1016 /* Finished with the check string */
1018 nl_check_length = nl_escape_length = 0;
1020 /* If requested, add a terminating "." line (SMTP output). */
1022 if (tctx->options & topt_end_dot && !write_chunk(fd, tctx, US".\n", 2))
1025 /* Write out any remaining data in the buffer before returning. */
1027 return (len = chunk_ptr - deliver_out_buffer) <= 0 ||
1028 transport_write_block(fd, deliver_out_buffer, len);
1032 #ifndef DISABLE_DKIM
1034 /***************************************************************************************************
1035 * External interface to write the message, while signing it with DKIM and/or Domainkeys *
1036 ***************************************************************************************************/
1038 /* This function is a wrapper around transport_write_message().
1039 It is only called from the smtp transport if DKIM or Domainkeys support
1040 is compiled in. The function sets up a replacement fd into a -K file,
1041 then calls the normal function. This way, the exact bits that exim would
1042 have put "on the wire" will end up in the file (except for TLS
1043 encapsulation, which is the very very last thing). When we are done
1044 signing the file, send the signed message down the original fd (or TLS fd).
1047 as for internal_transport_write_message() above, with additional arguments
1050 Returns: TRUE on success; FALSE (with errno) for any failure
1054 dkim_transport_write_message(int out_fd, transport_ctx * tctx,
1055 struct ob_dkim * dkim)
1060 uschar * dkim_spool_name;
1063 uschar *dkim_signature = NULL;
1068 /* If we can't sign, just call the original function. */
1070 if (!(dkim->dkim_private_key && dkim->dkim_domain && dkim->dkim_selector))
1071 return transport_write_message(out_fd, tctx, 0);
1073 dkim_spool_name = spool_fname(US"input", message_subdir, message_id,
1074 string_sprintf("-%d-K", (int)getpid()));
1076 if ((dkim_fd = Uopen(dkim_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE)) < 0)
1078 /* Can't create spool file. Ugh. */
1084 /* Call original function to write the -K file; does the CRLF expansion
1085 (but, in the CHUNKING case, not dot-stuffing and dot-termination). */
1087 options = tctx->options;
1088 tctx->options &= ~topt_use_bdat;
1089 rc = transport_write_message(dkim_fd, tctx, 0);
1090 tctx->options = options;
1092 /* Save error state. We must clean up before returning. */
1099 /* Rewind file and feed it to the goats^W DKIM lib */
1100 dkim->dot_stuffed = !!(options & topt_end_dot);
1101 lseek(dkim_fd, 0, SEEK_SET);
1102 if ((dkim_signature = dkim_exim_sign(dkim_fd, dkim)))
1103 siglen = Ustrlen(dkim_signature);
1104 else if (dkim->dkim_strict)
1106 uschar *dkim_strict_result = expand_string(dkim->dkim_strict);
1107 if (dkim_strict_result)
1108 if ( (strcmpic(dkim->dkim_strict,US"1") == 0) ||
1109 (strcmpic(dkim->dkim_strict,US"true") == 0) )
1111 /* Set errno to something halfway meaningful */
1112 save_errno = EACCES;
1113 log_write(0, LOG_MAIN, "DKIM: message could not be signed,"
1114 " and dkim_strict is set. Deferring message delivery.");
1120 #ifndef HAVE_LINUX_SENDFILE
1121 if (options & topt_use_bdat)
1123 k_file_size = lseek(dkim_fd, 0, SEEK_END); /* Fetch file size */
1125 if (options & topt_use_bdat)
1128 /* On big messages output a precursor chunk to get any pipelined
1129 MAIL & RCPT commands flushed, then reap the responses so we can
1130 error out on RCPT rejects before sending megabytes. */
1132 if (siglen + k_file_size > DELIVER_OUT_BUFFER_SIZE && siglen > 0)
1134 if ( tctx->chunk_cb(out_fd, tctx, siglen, 0) != OK
1135 || !transport_write_block(out_fd, dkim_signature, siglen)
1136 || tctx->chunk_cb(out_fd, tctx, 0, tc_reap_prev) != OK
1142 if (tctx->chunk_cb(out_fd, tctx, siglen + k_file_size, tc_chunk_last) != OK)
1146 if(siglen > 0 && !transport_write_block(out_fd, dkim_signature, siglen))
1149 #ifdef HAVE_LINUX_SENDFILE
1150 /* We can use sendfile() to shove the file contents
1151 to the socket. However only if we don't use TLS,
1152 as then there's another layer of indirection
1153 before the data finally hits the socket. */
1154 if (tls_out.active != out_fd)
1160 lseek(dkim_fd, 0, SEEK_SET);
1162 while(copied >= 0 && offset < k_file_size)
1163 copied = sendfile(out_fd, dkim_fd, &offset, k_file_size - offset);
1173 lseek(dkim_fd, 0, SEEK_SET);
1175 /* Send file down the original fd */
1176 while((sread = read(dkim_fd, deliver_out_buffer, DELIVER_OUT_BUFFER_SIZE)) >0)
1178 char *p = deliver_out_buffer;
1179 /* write the chunk */
1184 wwritten = tls_out.active == out_fd
1185 ? tls_write(FALSE, US p, sread)
1186 : write(out_fd, p, sread);
1188 wwritten = write(out_fd, p, sread);
1205 /* unlink -K file */
1206 (void)close(dkim_fd);
1207 Uunlink(dkim_spool_name);
1221 /*************************************************
1222 * External interface to write the message *
1223 *************************************************/
1225 /* If there is no filtering required, call the internal function above to do
1226 the real work, passing over all the arguments from this function. Otherwise,
1227 set up a filtering process, fork another process to call the internal function
1228 to write to the filter, and in this process just suck from the filter and write
1229 down the given fd. At the end, tidy up the pipes and the processes.
1232 Arguments: as for internal_transport_write_message() above
1234 Returns: TRUE on success; FALSE (with errno) for any failure
1235 transport_count is incremented by the number of bytes written
1239 transport_write_message(int fd, transport_ctx * tctx, int size_limit)
1242 BOOL last_filter_was_NL = TRUE;
1243 int rc, len, yield, fd_read, fd_write, save_errno;
1244 int pfd[2] = {-1, -1};
1245 pid_t filter_pid, write_pid;
1246 static transport_ctx dummy_tctx = {0};
1248 if (!tctx) tctx = &dummy_tctx;
1250 transport_filter_timed_out = FALSE;
1252 /* If there is no filter command set up, call the internal function that does
1253 the actual work, passing it the incoming fd, and return its result. */
1255 if ( !transport_filter_argv
1256 || !*transport_filter_argv
1257 || !**transport_filter_argv
1259 return internal_transport_write_message(fd, tctx, size_limit);
1261 /* Otherwise the message must be written to a filter process and read back
1262 before being written to the incoming fd. First set up the special processing to
1263 be done during the copying. */
1265 wck_flags = tctx->options & topt_use_crlf;
1266 nl_partial_match = -1;
1268 if (tctx->check_string && tctx->escape_string)
1270 nl_check = tctx->check_string;
1271 nl_check_length = Ustrlen(nl_check);
1272 nl_escape = tctx->escape_string;
1273 nl_escape_length = Ustrlen(nl_escape);
1275 else nl_check_length = nl_escape_length = 0;
1277 /* Start up a subprocess to run the command. Ensure that our main fd will
1278 be closed when the subprocess execs, but remove the flag afterwards.
1279 (Otherwise, if this is a TCP/IP socket, it can't get passed on to another
1280 process to deliver another message.) We get back stdin/stdout file descriptors.
1281 If the process creation failed, give an error return. */
1287 write_pid = (pid_t)(-1);
1289 (void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
1290 filter_pid = child_open(USS transport_filter_argv, NULL, 077,
1291 &fd_write, &fd_read, FALSE);
1292 (void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) & ~FD_CLOEXEC);
1293 if (filter_pid < 0) goto TIDY_UP; /* errno set */
1296 debug_printf("process %d running as transport filter: fd_write=%d fd_read=%d\n",
1297 (int)filter_pid, fd_write, fd_read);
1299 /* Fork subprocess to write the message to the filter, and return the result
1300 via a(nother) pipe. While writing to the filter, we do not do the CRLF,
1301 smtp dots, or check string processing. */
1303 if (pipe(pfd) != 0) goto TIDY_UP; /* errno set */
1304 if ((write_pid = fork()) == 0)
1307 (void)close(fd_read);
1308 (void)close(pfd[pipe_read]);
1309 nl_check_length = nl_escape_length = 0;
1311 tctx->check_string = tctx->escape_string = NULL;
1312 tctx->options &= ~(topt_use_crlf | topt_end_dot | topt_use_bdat);
1314 rc = internal_transport_write_message(fd_write, tctx, size_limit);
1317 if ( write(pfd[pipe_write], (void *)&rc, sizeof(BOOL))
1319 || write(pfd[pipe_write], (void *)&save_errno, sizeof(int))
1321 || write(pfd[pipe_write], (void *)&tctx->addr->more_errno, sizeof(int))
1324 rc = FALSE; /* compiler quietening */
1329 /* Parent process: close our copy of the writing subprocess' pipes. */
1331 (void)close(pfd[pipe_write]);
1332 (void)close(fd_write);
1335 /* Writing process creation failed */
1339 errno = save_errno; /* restore */
1343 /* When testing, let the subprocess get going */
1345 if (running_in_test_harness) millisleep(250);
1348 debug_printf("process %d writing to transport filter\n", (int)write_pid);
1350 /* Copy the message from the filter to the output fd. A read error leaves len
1351 == -1 and errno set. We need to apply a timeout to the read, to cope with
1352 the case when the filter gets stuck, but it can be quite a long one. The
1353 default is 5m, but this is now configurable. */
1355 DEBUG(D_transport) debug_printf("copying from the filter\n");
1357 /* Copy the output of the filter, remembering if the last character was NL. If
1358 no data is returned, that counts as "ended with NL" (default setting of the
1359 variable is TRUE). */
1361 chunk_ptr = deliver_out_buffer;
1365 sigalrm_seen = FALSE;
1366 alarm(transport_filter_timeout);
1367 len = read(fd_read, deliver_in_buffer, DELIVER_IN_BUFFER_SIZE);
1372 transport_filter_timed_out = TRUE;
1376 /* If the read was successful, write the block down the original fd,
1377 remembering whether it ends in \n or not. */
1381 if (!write_chunk(fd, tctx, deliver_in_buffer, len)) goto TIDY_UP;
1382 last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
1385 /* Otherwise, break the loop. If we have hit EOF, set yield = TRUE. */
1389 if (len == 0) yield = TRUE;
1394 /* Tidying up code. If yield = FALSE there has been an error and errno is set
1395 to something. Ensure the pipes are all closed and the processes are removed. If
1396 there has been an error, kill the processes before waiting for them, just to be
1397 sure. Also apply a paranoia timeout. */
1402 (void)close(fd_read);
1403 if (fd_write > 0) (void)close(fd_write);
1407 if (filter_pid > 0) kill(filter_pid, SIGKILL);
1408 if (write_pid > 0) kill(write_pid, SIGKILL);
1411 /* Wait for the filter process to complete. */
1413 DEBUG(D_transport) debug_printf("waiting for filter process\n");
1414 if (filter_pid > 0 && (rc = child_close(filter_pid, 30)) != 0 && yield)
1417 save_errno = ERRNO_FILTER_FAIL;
1418 tctx->addr->more_errno = rc;
1419 DEBUG(D_transport) debug_printf("filter process returned %d\n", rc);
1422 /* Wait for the writing process to complete. If it ends successfully,
1423 read the results from its pipe, provided we haven't already had a filter
1426 DEBUG(D_transport) debug_printf("waiting for writing process\n");
1429 rc = child_close(write_pid, 30);
1435 int dummy = read(pfd[pipe_read], (void *)&ok, sizeof(BOOL));
1438 dummy = read(pfd[pipe_read], (void *)&save_errno, sizeof(int));
1439 dummy = read(pfd[pipe_read], (void *)&(tctx->addr->more_errno), sizeof(int));
1446 save_errno = ERRNO_FILTER_FAIL;
1447 tctx->addr->more_errno = rc;
1448 DEBUG(D_transport) debug_printf("writing process returned %d\n", rc);
1452 (void)close(pfd[pipe_read]);
1454 /* If there have been no problems we can now add the terminating "." if this is
1455 SMTP output, turning off escaping beforehand. If the last character from the
1456 filter was not NL, insert a NL to make the SMTP protocol work. */
1460 nl_check_length = nl_escape_length = 0;
1461 if ( tctx->options & topt_end_dot
1462 && ( last_filter_was_NL
1463 ? !write_chunk(fd, tctx, US".\n", 2)
1464 : !write_chunk(fd, tctx, US"\n.\n", 3)
1468 /* Write out any remaining data in the buffer. */
1471 yield = (len = chunk_ptr - deliver_out_buffer) <= 0
1472 || transport_write_block(fd, deliver_out_buffer, len);
1475 errno = save_errno; /* From some earlier error */
1479 debug_printf("end of filtering transport writing: yield=%d\n", yield);
1481 debug_printf("errno=%d more_errno=%d\n", errno, tctx->addr->more_errno);
1491 /*************************************************
1492 * Update waiting database *
1493 *************************************************/
1495 /* This is called when an address is deferred by remote transports that are
1496 capable of sending more than one message over one connection. A database is
1497 maintained for each transport, keeping track of which messages are waiting for
1498 which hosts. The transport can then consult this when eventually a successful
1499 delivery happens, and if it finds that another message is waiting for the same
1500 host, it can fire up a new process to deal with it using the same connection.
1502 The database records are keyed by host name. They can get full if there are
1503 lots of messages waiting, and so there is a continuation mechanism for them.
1505 Each record contains a list of message ids, packed end to end without any
1506 zeros. Each one is MESSAGE_ID_LENGTH bytes long. The count field says how many
1507 in this record, and the sequence field says if there are any other records for
1508 this host. If the sequence field is 0, there are none. If it is 1, then another
1509 record with the name <hostname>:0 exists; if it is 2, then two other records
1510 with sequence numbers 0 and 1 exist, and so on.
1512 Currently, an exhaustive search of all continuation records has to be done to
1513 determine whether to add a message id to a given record. This shouldn't be
1514 too bad except in extreme cases. I can't figure out a *simple* way of doing
1517 Old records should eventually get swept up by the exim_tidydb utility.
1520 hostlist list of hosts that this message could be sent to
1521 tpname name of the transport
1527 transport_update_waiting(host_item *hostlist, uschar *tpname)
1530 const uschar *prevname = US"";
1535 DEBUG(D_transport) debug_printf("updating wait-%s database\n", tpname);
1537 /* Open the database for this transport */
1539 sprintf(CS buffer, "wait-%.200s", tpname);
1540 dbm_file = dbfn_open(buffer, O_RDWR, &dbblock, TRUE);
1541 if (dbm_file == NULL) return;
1543 /* Scan the list of hosts for which this message is waiting, and ensure
1544 that the message id is in each host record. */
1546 for (host = hostlist; host!= NULL; host = host->next)
1548 BOOL already = FALSE;
1549 dbdata_wait *host_record;
1553 /* Skip if this is the same host as we just processed; otherwise remember
1554 the name for next time. */
1556 if (Ustrcmp(prevname, host->name) == 0) continue;
1557 prevname = host->name;
1559 /* Look up the host record; if there isn't one, make an empty one. */
1561 host_record = dbfn_read(dbm_file, host->name);
1562 if (host_record == NULL)
1564 host_record = store_get(sizeof(dbdata_wait) + MESSAGE_ID_LENGTH);
1565 host_record->count = host_record->sequence = 0;
1568 /* Compute the current length */
1570 host_length = host_record->count * MESSAGE_ID_LENGTH;
1572 /* Search the record to see if the current message is already in it. */
1574 for (s = host_record->text; s < host_record->text + host_length;
1575 s += MESSAGE_ID_LENGTH)
1577 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1578 { already = TRUE; break; }
1581 /* If we haven't found this message in the main record, search any
1582 continuation records that exist. */
1584 for (i = host_record->sequence - 1; i >= 0 && !already; i--)
1587 sprintf(CS buffer, "%.200s:%d", host->name, i);
1588 cont = dbfn_read(dbm_file, buffer);
1591 int clen = cont->count * MESSAGE_ID_LENGTH;
1592 for (s = cont->text; s < cont->text + clen; s += MESSAGE_ID_LENGTH)
1594 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1595 { already = TRUE; break; }
1600 /* If this message is already in a record, no need to update. */
1604 DEBUG(D_transport) debug_printf("already listed for %s\n", host->name);
1609 /* If this record is full, write it out with a new name constructed
1610 from the sequence number, increase the sequence number, and empty
1613 if (host_record->count >= WAIT_NAME_MAX)
1615 sprintf(CS buffer, "%.200s:%d", host->name, host_record->sequence);
1616 dbfn_write(dbm_file, buffer, host_record, sizeof(dbdata_wait) + host_length);
1617 host_record->sequence++;
1618 host_record->count = 0;
1622 /* If this record is not full, increase the size of the record to
1623 allow for one new message id. */
1628 store_get(sizeof(dbdata_wait) + host_length + MESSAGE_ID_LENGTH);
1629 memcpy(newr, host_record, sizeof(dbdata_wait) + host_length);
1633 /* Now add the new name on the end */
1635 memcpy(host_record->text + host_length, message_id, MESSAGE_ID_LENGTH);
1636 host_record->count++;
1637 host_length += MESSAGE_ID_LENGTH;
1639 /* Update the database */
1641 dbfn_write(dbm_file, host->name, host_record, sizeof(dbdata_wait) + host_length);
1642 DEBUG(D_transport) debug_printf("added to list for %s\n", host->name);
1647 dbfn_close(dbm_file);
1653 /*************************************************
1654 * Test for waiting messages *
1655 *************************************************/
1657 /* This function is called by a remote transport which uses the previous
1658 function to remember which messages are waiting for which remote hosts. It's
1659 called after a successful delivery and its job is to check whether there is
1660 another message waiting for the same host. However, it doesn't do this if the
1661 current continue sequence is greater than the maximum supplied as an argument,
1662 or greater than the global connection_max_messages, which, if set, overrides.
1665 transport_name name of the transport
1666 hostname name of the host
1667 local_message_max maximum number of messages down one connection
1668 as set by the caller transport
1669 new_message_id set to the message id of a waiting message
1670 more set TRUE if there are yet more messages waiting
1671 oicf_func function to call to validate if it is ok to send
1672 to this message_id from the current instance.
1673 oicf_data opaque data for oicf_func
1675 Returns: TRUE if new_message_id set; FALSE otherwise
1678 typedef struct msgq_s
1680 uschar message_id [MESSAGE_ID_LENGTH + 1];
1685 transport_check_waiting(const uschar *transport_name, const uschar *hostname,
1686 int local_message_max, uschar *new_message_id, BOOL *more, oicf oicf_func, void *oicf_data)
1688 dbdata_wait *host_record;
1695 struct stat statbuf;
1701 debug_printf("transport_check_waiting entered\n");
1702 debug_printf(" sequence=%d local_max=%d global_max=%d\n",
1703 continue_sequence, local_message_max, connection_max_messages);
1706 /* Do nothing if we have hit the maximum number that can be send down one
1709 if (connection_max_messages >= 0) local_message_max = connection_max_messages;
1710 if (local_message_max > 0 && continue_sequence >= local_message_max)
1713 debug_printf("max messages for one connection reached: returning\n");
1717 /* Open the waiting information database. */
1719 sprintf(CS buffer, "wait-%.200s", transport_name);
1720 dbm_file = dbfn_open(buffer, O_RDWR, &dbblock, TRUE);
1721 if (dbm_file == NULL) return FALSE;
1723 /* See if there is a record for this host; if not, there's nothing to do. */
1725 if (!(host_record = dbfn_read(dbm_file, hostname)))
1727 dbfn_close(dbm_file);
1728 DEBUG(D_transport) debug_printf("no messages waiting for %s\n", hostname);
1732 /* If the data in the record looks corrupt, just log something and
1733 don't try to use it. */
1735 if (host_record->count > WAIT_NAME_MAX)
1737 dbfn_close(dbm_file);
1738 log_write(0, LOG_MAIN|LOG_PANIC, "smtp-wait database entry for %s has bad "
1739 "count=%d (max=%d)", hostname, host_record->count, WAIT_NAME_MAX);
1743 /* Scan the message ids in the record from the end towards the beginning,
1744 until one is found for which a spool file actually exists. If the record gets
1745 emptied, delete it and continue with any continuation records that may exist.
1748 /* For Bug 1141, I refactored this major portion of the routine, it is risky
1749 but the 1 off will remain without it. This code now allows me to SKIP over
1750 a message I do not want to send out on this run. */
1752 host_length = host_record->count * MESSAGE_ID_LENGTH;
1758 int msgq_actual = 0;
1759 BOOL bFound = FALSE;
1760 BOOL bContinuation = FALSE;
1762 /* create an array to read entire message queue into memory for processing */
1764 msgq = (msgq_t*) malloc(sizeof(msgq_t) * host_record->count);
1765 msgq_count = host_record->count;
1766 msgq_actual = msgq_count;
1768 for (i = 0; i < host_record->count; ++i)
1770 msgq[i].bKeep = TRUE;
1772 Ustrncpy(msgq[i].message_id, host_record->text + (i * MESSAGE_ID_LENGTH),
1774 msgq[i].message_id[MESSAGE_ID_LENGTH] = 0;
1777 /* first thing remove current message id if it exists */
1779 for (i = 0; i < msgq_count; ++i)
1780 if (Ustrcmp(msgq[i].message_id, message_id) == 0)
1782 msgq[i].bKeep = FALSE;
1786 /* now find the next acceptable message_id */
1788 for (i = msgq_count - 1; i >= 0; --i) if (msgq[i].bKeep)
1792 subdir[0] = split_spool_directory ? msgq[i].message_id[5] : 0;
1795 if (Ustat(spool_fname(US"input", subdir, msgq[i].message_id, US"-D"),
1797 msgq[i].bKeep = FALSE;
1798 else if (!oicf_func || oicf_func(msgq[i].message_id, oicf_data))
1800 Ustrcpy(new_message_id, msgq[i].message_id);
1801 msgq[i].bKeep = FALSE;
1808 for (msgq_actual = 0, i = 0; i < msgq_count; ++i)
1812 /* reassemble the host record, based on removed message ids, from in
1815 if (msgq_actual <= 0)
1818 host_record->count = 0;
1822 host_length = msgq_actual * MESSAGE_ID_LENGTH;
1823 host_record->count = msgq_actual;
1825 if (msgq_actual < msgq_count)
1828 for (new_count = 0, i = 0; i < msgq_count; ++i)
1830 Ustrncpy(&host_record->text[new_count++ * MESSAGE_ID_LENGTH],
1831 msgq[i].message_id, MESSAGE_ID_LENGTH);
1833 host_record->text[new_count * MESSAGE_ID_LENGTH] = 0;
1837 /* Jeremy: check for a continuation record, this code I do not know how to
1838 test but the code should work */
1840 while (host_length <= 0)
1843 dbdata_wait * newr = NULL;
1845 /* Search for a continuation */
1847 for (i = host_record->sequence - 1; i >= 0 && !newr; i--)
1849 sprintf(CS buffer, "%.200s:%d", hostname, i);
1850 newr = dbfn_read(dbm_file, buffer);
1853 /* If no continuation, delete the current and break the loop */
1857 dbfn_delete(dbm_file, hostname);
1861 /* Else replace the current with the continuation */
1863 dbfn_delete(dbm_file, buffer);
1865 host_length = host_record->count * MESSAGE_ID_LENGTH;
1867 bContinuation = TRUE;
1870 if (bFound) /* Usual exit from main loop */
1876 /* If host_length <= 0 we have emptied a record and not found a good message,
1877 and there are no continuation records. Otherwise there is a continuation
1878 record to process. */
1880 if (host_length <= 0)
1882 dbfn_close(dbm_file);
1883 DEBUG(D_transport) debug_printf("waiting messages already delivered\n");
1887 /* we were not able to find an acceptable message, nor was there a
1888 * continuation record. So bug out, outer logic will clean this up.
1893 Ustrcpy(new_message_id, message_id);
1894 dbfn_close(dbm_file);
1899 } /* we need to process a continuation record */
1901 /* Control gets here when an existing message has been encountered; its
1902 id is in new_message_id, and host_length is the revised length of the
1903 host record. If it is zero, the record has been removed. Update the
1904 record if required, close the database, and return TRUE. */
1906 if (host_length > 0)
1908 host_record->count = host_length/MESSAGE_ID_LENGTH;
1910 dbfn_write(dbm_file, hostname, host_record, (int)sizeof(dbdata_wait) + host_length);
1914 dbfn_close(dbm_file);
1918 /*************************************************
1919 * Deliver waiting message down same socket *
1920 *************************************************/
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)
1948 const uschar **argv;
1950 /* Disconnect entirely from the parent process. If we are running in the
1951 test harness, wait for a bit to allow the previous process time to finish,
1952 write the log, etc., so that the output is always in the same order for
1953 automatic comparison. */
1955 if ((pid = fork()) != 0) _exit(EXIT_SUCCESS);
1956 if (running_in_test_harness) sleep(1);
1958 /* Set up the calling arguments; use the standard function for the basics,
1959 but we have a number of extras that may be added. */
1961 argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, &i, FALSE, 0);
1963 if (smtp_authenticated) argv[i++] = US"-MCA";
1965 if (smtp_peer_options & PEER_OFFERED_CHUNKING) argv[i++] = US"-MCK";
1966 if (smtp_peer_options & PEER_OFFERED_DSN) argv[i++] = US"-MCD";
1967 if (smtp_peer_options & PEER_OFFERED_PIPE) argv[i++] = US"-MCP";
1968 if (smtp_peer_options & PEER_OFFERED_SIZE) argv[i++] = US"-MCS";
1970 if (smtp_peer_options & PEER_OFFERED_TLS) argv[i++] = US"-MCT";
1973 if (queue_run_pid != (pid_t)0)
1975 argv[i++] = US"-MCQ";
1976 argv[i++] = string_sprintf("%d", queue_run_pid);
1977 argv[i++] = string_sprintf("%d", queue_run_pipe);
1980 argv[i++] = US"-MC";
1981 argv[i++] = US transport_name;
1982 argv[i++] = US hostname;
1983 argv[i++] = US hostaddress;
1984 argv[i++] = string_sprintf("%d", continue_sequence + 1);
1988 /* Arrange for the channel to be on stdin. */
1992 (void)dup2(socket_fd, 0);
1993 (void)close(socket_fd);
1996 DEBUG(D_exec) debug_print_argv(argv);
1997 exim_nullstd(); /* Ensure std{out,err} exist */
1998 execv(CS argv[0], (char *const *)argv);
2000 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
2001 _exit(errno); /* Note: must be _exit(), NOT exit() */
2004 /* If the process creation succeeded, wait for the first-level child, which
2005 immediately exits, leaving the second level process entirely disconnected from
2011 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
2012 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded\n");
2017 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
2025 /*************************************************
2026 * Set up direct (non-shell) command *
2027 *************************************************/
2029 /* This function is called when a command line is to be parsed and executed
2030 directly, without the use of /bin/sh. It is called by the pipe transport,
2031 the queryprogram router, and also from the main delivery code when setting up a
2032 transport filter process. The code for ETRN also makes use of this; in that
2033 case, no addresses are passed.
2036 argvptr pointer to anchor for argv vector
2037 cmd points to the command string (modified IN PLACE)
2038 expand_arguments true if expansion is to occur
2039 expand_failed error value to set if expansion fails; not relevant if
2041 addr chain of addresses, or NULL
2042 etext text for use in error messages
2043 errptr where to put error message if addr is NULL;
2044 otherwise it is put in the first address
2046 Returns: TRUE if all went well; otherwise an error will be
2047 set in the first address and FALSE returned
2051 transport_set_up_command(const uschar ***argvptr, uschar *cmd,
2052 BOOL expand_arguments, int expand_failed, address_item *addr,
2053 uschar *etext, uschar **errptr)
2056 const uschar **argv;
2058 int address_count = 0;
2062 /* Get store in which to build an argument list. Count the number of addresses
2063 supplied, and allow for that many arguments, plus an additional 60, which
2064 should be enough for anybody. Multiple addresses happen only when the local
2065 delivery batch option is set. */
2067 for (ad = addr; ad != NULL; ad = ad->next) address_count++;
2068 max_args = address_count + 60;
2069 *argvptr = argv = store_get((max_args+1)*sizeof(uschar *));
2071 /* Split the command up into arguments terminated by white space. Lose
2072 trailing space at the start and end. Double-quoted arguments can contain \\ and
2073 \" escapes and so can be handled by the standard function; single-quoted
2074 arguments are verbatim. Copy each argument into a new string. */
2077 while (isspace(*s)) s++;
2079 while (*s != 0 && argcount < max_args)
2084 while (*ss != 0 && *ss != '\'') ss++;
2085 argv[argcount++] = ss = store_get(ss - s++);
2086 while (*s != 0 && *s != '\'') *ss++ = *s++;
2090 else argv[argcount++] = string_copy(string_dequote(CUSS &s));
2091 while (isspace(*s)) s++;
2094 argv[argcount] = (uschar *)0;
2096 /* If *s != 0 we have run out of argument slots. */
2100 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
2104 addr->transport_return = FAIL;
2105 addr->message = msg;
2111 /* Expand each individual argument if required. Expansion happens for pipes set
2112 up in filter files and with directly-supplied commands. It does not happen if
2113 the pipe comes from a traditional .forward file. A failing expansion is a big
2114 disaster if the command came from Exim's configuration; if it came from a user
2115 it is just a normal failure. The expand_failed value is used as the error value
2116 to cater for these two cases.
2118 An argument consisting just of the text "$pipe_addresses" is treated specially.
2119 It is not passed to the general expansion function. Instead, it is replaced by
2120 a number of arguments, one for each address. This avoids problems with shell
2121 metacharacters and spaces in addresses.
2123 If the parent of the top address has an original part of "system-filter", this
2124 pipe was set up by the system filter, and we can permit the expansion of
2129 debug_printf("direct command:\n");
2130 for (i = 0; argv[i] != (uschar *)0; i++)
2131 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2134 if (expand_arguments)
2136 BOOL allow_dollar_recipients = addr != NULL &&
2137 addr->parent != NULL &&
2138 Ustrcmp(addr->parent->address, "system-filter") == 0;
2140 for (i = 0; argv[i] != (uschar *)0; i++)
2143 /* Handle special fudge for passing an address list */
2146 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
2147 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
2151 if (argcount + address_count - 1 > max_args)
2153 addr->transport_return = FAIL;
2154 addr->message = string_sprintf("Too many arguments to command \"%s\" "
2155 "in %s", cmd, etext);
2159 additional = address_count - 1;
2161 memmove(argv + i + 1 + additional, argv + i + 1,
2162 (argcount - i)*sizeof(uschar *));
2164 for (ad = addr; ad != NULL; ad = ad->next) {
2165 argv[i++] = ad->address;
2169 /* Subtract one since we replace $pipe_addresses */
2174 /* Handle special case of $address_pipe when af_force_command is set */
2176 else if (addr != NULL && testflag(addr,af_force_command) &&
2177 (Ustrcmp(argv[i], "$address_pipe") == 0 ||
2178 Ustrcmp(argv[i], "${address_pipe}") == 0))
2181 int address_pipe_argcount = 0;
2182 int address_pipe_max_args;
2183 uschar **address_pipe_argv;
2185 /* We can never have more then the argv we will be loading into */
2186 address_pipe_max_args = max_args - argcount + 1;
2189 debug_printf("address_pipe_max_args=%d\n", address_pipe_max_args);
2191 /* We allocate an additional for (uschar *)0 */
2192 address_pipe_argv = store_get((address_pipe_max_args+1)*sizeof(uschar *));
2194 /* +1 because addr->local_part[0] == '|' since af_force_command is set */
2195 s = expand_string(addr->local_part + 1);
2197 if (s == NULL || *s == '\0')
2199 addr->transport_return = FAIL;
2200 addr->message = string_sprintf("Expansion of \"%s\" "
2201 "from command \"%s\" in %s failed: %s",
2202 (addr->local_part + 1), cmd, etext, expand_string_message);
2206 while (isspace(*s)) s++; /* strip leading space */
2208 while (*s != 0 && address_pipe_argcount < address_pipe_max_args)
2213 while (*ss != 0 && *ss != '\'') ss++;
2214 address_pipe_argv[address_pipe_argcount++] = ss = store_get(ss - s++);
2215 while (*s != 0 && *s != '\'') *ss++ = *s++;
2219 else address_pipe_argv[address_pipe_argcount++] =
2220 string_copy(string_dequote(CUSS &s));
2221 while (isspace(*s)) s++; /* strip space after arg */
2224 address_pipe_argv[address_pipe_argcount] = (uschar *)0;
2226 /* If *s != 0 we have run out of argument slots. */
2229 uschar *msg = string_sprintf("Too many arguments in $address_pipe "
2230 "\"%s\" in %s", addr->local_part + 1, etext);
2233 addr->transport_return = FAIL;
2234 addr->message = msg;
2240 /* address_pipe_argcount - 1
2241 * because we are replacing $address_pipe in the argument list
2242 * with the first thing it expands to */
2243 if (argcount + address_pipe_argcount - 1 > max_args)
2245 addr->transport_return = FAIL;
2246 addr->message = string_sprintf("Too many arguments to command "
2247 "\"%s\" after expanding $address_pipe in %s", cmd, etext);
2251 /* If we are not just able to replace the slot that contained
2252 * $address_pipe (address_pipe_argcount == 1)
2253 * We have to move the existing argv by address_pipe_argcount - 1
2254 * Visually if address_pipe_argcount == 2:
2255 * [argv 0][argv 1][argv 2($address_pipe)][argv 3][0]
2256 * [argv 0][argv 1][ap_arg0][ap_arg1][old argv 3][0]
2258 if (address_pipe_argcount > 1)
2260 /* current position + additonal args */
2261 argv + i + address_pipe_argcount,
2262 /* current position + 1 (for the (uschar *)0 at the end) */
2264 /* -1 for the (uschar *)0 at the end)*/
2265 (argcount - i)*sizeof(uschar *)
2268 /* Now we fill in the slots we just moved argv out of
2269 * [argv 0][argv 1][argv 2=pipeargv[0]][argv 3=pipeargv[1]][old argv 3][0]
2271 for (address_pipe_i = 0;
2272 address_pipe_argv[address_pipe_i] != (uschar *)0;
2275 argv[i++] = address_pipe_argv[address_pipe_i];
2279 /* Subtract one since we replace $address_pipe */
2284 /* Handle normal expansion string */
2288 const uschar *expanded_arg;
2289 enable_dollar_recipients = allow_dollar_recipients;
2290 expanded_arg = expand_cstring(argv[i]);
2291 enable_dollar_recipients = FALSE;
2293 if (expanded_arg == NULL)
2295 uschar *msg = string_sprintf("Expansion of \"%s\" "
2296 "from command \"%s\" in %s failed: %s",
2297 argv[i], cmd, etext, expand_string_message);
2300 addr->transport_return = expand_failed;
2301 addr->message = msg;
2306 argv[i] = expanded_arg;
2312 debug_printf("direct command after expansion:\n");
2313 for (i = 0; argv[i] != (uschar *)0; i++)
2314 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2323 /* End of transport.c */