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 */
1086 options = tctx->options;
1087 tctx->options &= ~topt_use_bdat;
1088 rc = transport_write_message(dkim_fd, tctx, 0);
1089 tctx->options = options;
1091 /* Save error state. We must clean up before returning. */
1098 /* Rewind file and feed it to the goats^W DKIM lib */
1099 lseek(dkim_fd, 0, SEEK_SET);
1100 dkim_signature = dkim_exim_sign(dkim_fd,
1101 dkim->dkim_private_key,
1103 dkim->dkim_selector,
1105 dkim->dkim_sign_headers);
1107 siglen = Ustrlen(dkim_signature);
1108 else if (dkim->dkim_strict)
1110 uschar *dkim_strict_result = expand_string(dkim->dkim_strict);
1111 if (dkim_strict_result)
1112 if ( (strcmpic(dkim->dkim_strict,US"1") == 0) ||
1113 (strcmpic(dkim->dkim_strict,US"true") == 0) )
1115 /* Set errno to something halfway meaningful */
1116 save_errno = EACCES;
1117 log_write(0, LOG_MAIN, "DKIM: message could not be signed,"
1118 " and dkim_strict is set. Deferring message delivery.");
1124 #ifndef HAVE_LINUX_SENDFILE
1125 if (options & topt_use_bdat)
1127 k_file_size = lseek(dkim_fd, 0, SEEK_END); /* Fetch file size */
1129 if (options & topt_use_bdat)
1132 /* On big messages output a precursor chunk to get any pipelined
1133 MAIL & RCPT commands flushed, then reap the responses so we can
1134 error out on RCPT rejects before sending megabytes. */
1136 if (siglen + k_file_size > DELIVER_OUT_BUFFER_SIZE && siglen > 0)
1138 if ( tctx->chunk_cb(out_fd, tctx, siglen, 0) != OK
1139 || !transport_write_block(out_fd, dkim_signature, siglen)
1140 || tctx->chunk_cb(out_fd, tctx, 0, tc_reap_prev) != OK
1146 if (tctx->chunk_cb(out_fd, tctx, siglen + k_file_size, tc_chunk_last) != OK)
1150 if(siglen > 0 && !transport_write_block(out_fd, dkim_signature, siglen))
1153 #ifdef HAVE_LINUX_SENDFILE
1154 /* We can use sendfile() to shove the file contents
1155 to the socket. However only if we don't use TLS,
1156 as then there's another layer of indirection
1157 before the data finally hits the socket. */
1158 if (tls_out.active != out_fd)
1164 lseek(dkim_fd, 0, SEEK_SET);
1166 while(copied >= 0 && offset < k_file_size)
1167 copied = sendfile(out_fd, dkim_fd, &offset, k_file_size - offset);
1177 lseek(dkim_fd, 0, SEEK_SET);
1179 /* Send file down the original fd */
1180 while((sread = read(dkim_fd, deliver_out_buffer, DELIVER_OUT_BUFFER_SIZE)) >0)
1182 char *p = deliver_out_buffer;
1183 /* write the chunk */
1188 wwritten = tls_out.active == out_fd
1189 ? tls_write(FALSE, US p, sread)
1190 : write(out_fd, p, sread);
1192 wwritten = write(out_fd, p, sread);
1209 /* unlink -K file */
1210 (void)close(dkim_fd);
1211 Uunlink(dkim_spool_name);
1225 /*************************************************
1226 * External interface to write the message *
1227 *************************************************/
1229 /* If there is no filtering required, call the internal function above to do
1230 the real work, passing over all the arguments from this function. Otherwise,
1231 set up a filtering process, fork another process to call the internal function
1232 to write to the filter, and in this process just suck from the filter and write
1233 down the given fd. At the end, tidy up the pipes and the processes.
1236 Arguments: as for internal_transport_write_message() above
1238 Returns: TRUE on success; FALSE (with errno) for any failure
1239 transport_count is incremented by the number of bytes written
1243 transport_write_message(int fd, transport_ctx * tctx, int size_limit)
1246 BOOL last_filter_was_NL = TRUE;
1247 int rc, len, yield, fd_read, fd_write, save_errno;
1248 int pfd[2] = {-1, -1};
1249 pid_t filter_pid, write_pid;
1250 static transport_ctx dummy_tctx = {0};
1252 if (!tctx) tctx = &dummy_tctx;
1254 transport_filter_timed_out = FALSE;
1256 /* If there is no filter command set up, call the internal function that does
1257 the actual work, passing it the incoming fd, and return its result. */
1259 if ( !transport_filter_argv
1260 || !*transport_filter_argv
1261 || !**transport_filter_argv
1263 return internal_transport_write_message(fd, tctx, size_limit);
1265 /* Otherwise the message must be written to a filter process and read back
1266 before being written to the incoming fd. First set up the special processing to
1267 be done during the copying. */
1269 wck_flags = tctx->options & topt_use_crlf;
1270 nl_partial_match = -1;
1272 if (tctx->check_string && tctx->escape_string)
1274 nl_check = tctx->check_string;
1275 nl_check_length = Ustrlen(nl_check);
1276 nl_escape = tctx->escape_string;
1277 nl_escape_length = Ustrlen(nl_escape);
1279 else nl_check_length = nl_escape_length = 0;
1281 /* Start up a subprocess to run the command. Ensure that our main fd will
1282 be closed when the subprocess execs, but remove the flag afterwards.
1283 (Otherwise, if this is a TCP/IP socket, it can't get passed on to another
1284 process to deliver another message.) We get back stdin/stdout file descriptors.
1285 If the process creation failed, give an error return. */
1291 write_pid = (pid_t)(-1);
1293 (void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
1294 filter_pid = child_open(USS transport_filter_argv, NULL, 077,
1295 &fd_write, &fd_read, FALSE);
1296 (void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) & ~FD_CLOEXEC);
1297 if (filter_pid < 0) goto TIDY_UP; /* errno set */
1300 debug_printf("process %d running as transport filter: fd_write=%d fd_read=%d\n",
1301 (int)filter_pid, fd_write, fd_read);
1303 /* Fork subprocess to write the message to the filter, and return the result
1304 via a(nother) pipe. While writing to the filter, we do not do the CRLF,
1305 smtp dots, or check string processing. */
1307 if (pipe(pfd) != 0) goto TIDY_UP; /* errno set */
1308 if ((write_pid = fork()) == 0)
1311 (void)close(fd_read);
1312 (void)close(pfd[pipe_read]);
1313 nl_check_length = nl_escape_length = 0;
1315 tctx->check_string = tctx->escape_string = NULL;
1316 tctx->options &= ~(topt_use_crlf | topt_end_dot | topt_use_bdat);
1318 rc = internal_transport_write_message(fd_write, tctx, size_limit);
1321 if ( write(pfd[pipe_write], (void *)&rc, sizeof(BOOL))
1323 || write(pfd[pipe_write], (void *)&save_errno, sizeof(int))
1325 || write(pfd[pipe_write], (void *)&tctx->addr->more_errno, sizeof(int))
1328 rc = FALSE; /* compiler quietening */
1333 /* Parent process: close our copy of the writing subprocess' pipes. */
1335 (void)close(pfd[pipe_write]);
1336 (void)close(fd_write);
1339 /* Writing process creation failed */
1343 errno = save_errno; /* restore */
1347 /* When testing, let the subprocess get going */
1349 if (running_in_test_harness) millisleep(250);
1352 debug_printf("process %d writing to transport filter\n", (int)write_pid);
1354 /* Copy the message from the filter to the output fd. A read error leaves len
1355 == -1 and errno set. We need to apply a timeout to the read, to cope with
1356 the case when the filter gets stuck, but it can be quite a long one. The
1357 default is 5m, but this is now configurable. */
1359 DEBUG(D_transport) debug_printf("copying from the filter\n");
1361 /* Copy the output of the filter, remembering if the last character was NL. If
1362 no data is returned, that counts as "ended with NL" (default setting of the
1363 variable is TRUE). */
1365 chunk_ptr = deliver_out_buffer;
1369 sigalrm_seen = FALSE;
1370 alarm(transport_filter_timeout);
1371 len = read(fd_read, deliver_in_buffer, DELIVER_IN_BUFFER_SIZE);
1376 transport_filter_timed_out = TRUE;
1380 /* If the read was successful, write the block down the original fd,
1381 remembering whether it ends in \n or not. */
1385 if (!write_chunk(fd, tctx, deliver_in_buffer, len)) goto TIDY_UP;
1386 last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
1389 /* Otherwise, break the loop. If we have hit EOF, set yield = TRUE. */
1393 if (len == 0) yield = TRUE;
1398 /* Tidying up code. If yield = FALSE there has been an error and errno is set
1399 to something. Ensure the pipes are all closed and the processes are removed. If
1400 there has been an error, kill the processes before waiting for them, just to be
1401 sure. Also apply a paranoia timeout. */
1406 (void)close(fd_read);
1407 if (fd_write > 0) (void)close(fd_write);
1411 if (filter_pid > 0) kill(filter_pid, SIGKILL);
1412 if (write_pid > 0) kill(write_pid, SIGKILL);
1415 /* Wait for the filter process to complete. */
1417 DEBUG(D_transport) debug_printf("waiting for filter process\n");
1418 if (filter_pid > 0 && (rc = child_close(filter_pid, 30)) != 0 && yield)
1421 save_errno = ERRNO_FILTER_FAIL;
1422 tctx->addr->more_errno = rc;
1423 DEBUG(D_transport) debug_printf("filter process returned %d\n", rc);
1426 /* Wait for the writing process to complete. If it ends successfully,
1427 read the results from its pipe, provided we haven't already had a filter
1430 DEBUG(D_transport) debug_printf("waiting for writing process\n");
1433 rc = child_close(write_pid, 30);
1439 int dummy = read(pfd[pipe_read], (void *)&ok, sizeof(BOOL));
1442 dummy = read(pfd[pipe_read], (void *)&save_errno, sizeof(int));
1443 dummy = read(pfd[pipe_read], (void *)&(tctx->addr->more_errno), sizeof(int));
1450 save_errno = ERRNO_FILTER_FAIL;
1451 tctx->addr->more_errno = rc;
1452 DEBUG(D_transport) debug_printf("writing process returned %d\n", rc);
1456 (void)close(pfd[pipe_read]);
1458 /* If there have been no problems we can now add the terminating "." if this is
1459 SMTP output, turning off escaping beforehand. If the last character from the
1460 filter was not NL, insert a NL to make the SMTP protocol work. */
1464 nl_check_length = nl_escape_length = 0;
1465 if ( tctx->options & topt_end_dot
1466 && ( last_filter_was_NL
1467 ? !write_chunk(fd, tctx, US".\n", 2)
1468 : !write_chunk(fd, tctx, US"\n.\n", 3)
1472 /* Write out any remaining data in the buffer. */
1475 yield = (len = chunk_ptr - deliver_out_buffer) <= 0
1476 || transport_write_block(fd, deliver_out_buffer, len);
1479 errno = save_errno; /* From some earlier error */
1483 debug_printf("end of filtering transport writing: yield=%d\n", yield);
1485 debug_printf("errno=%d more_errno=%d\n", errno, tctx->addr->more_errno);
1495 /*************************************************
1496 * Update waiting database *
1497 *************************************************/
1499 /* This is called when an address is deferred by remote transports that are
1500 capable of sending more than one message over one connection. A database is
1501 maintained for each transport, keeping track of which messages are waiting for
1502 which hosts. The transport can then consult this when eventually a successful
1503 delivery happens, and if it finds that another message is waiting for the same
1504 host, it can fire up a new process to deal with it using the same connection.
1506 The database records are keyed by host name. They can get full if there are
1507 lots of messages waiting, and so there is a continuation mechanism for them.
1509 Each record contains a list of message ids, packed end to end without any
1510 zeros. Each one is MESSAGE_ID_LENGTH bytes long. The count field says how many
1511 in this record, and the sequence field says if there are any other records for
1512 this host. If the sequence field is 0, there are none. If it is 1, then another
1513 record with the name <hostname>:0 exists; if it is 2, then two other records
1514 with sequence numbers 0 and 1 exist, and so on.
1516 Currently, an exhaustive search of all continuation records has to be done to
1517 determine whether to add a message id to a given record. This shouldn't be
1518 too bad except in extreme cases. I can't figure out a *simple* way of doing
1521 Old records should eventually get swept up by the exim_tidydb utility.
1524 hostlist list of hosts that this message could be sent to
1525 tpname name of the transport
1531 transport_update_waiting(host_item *hostlist, uschar *tpname)
1534 const uschar *prevname = US"";
1539 DEBUG(D_transport) debug_printf("updating wait-%s database\n", tpname);
1541 /* Open the database for this transport */
1543 sprintf(CS buffer, "wait-%.200s", tpname);
1544 dbm_file = dbfn_open(buffer, O_RDWR, &dbblock, TRUE);
1545 if (dbm_file == NULL) return;
1547 /* Scan the list of hosts for which this message is waiting, and ensure
1548 that the message id is in each host record. */
1550 for (host = hostlist; host!= NULL; host = host->next)
1552 BOOL already = FALSE;
1553 dbdata_wait *host_record;
1557 /* Skip if this is the same host as we just processed; otherwise remember
1558 the name for next time. */
1560 if (Ustrcmp(prevname, host->name) == 0) continue;
1561 prevname = host->name;
1563 /* Look up the host record; if there isn't one, make an empty one. */
1565 host_record = dbfn_read(dbm_file, host->name);
1566 if (host_record == NULL)
1568 host_record = store_get(sizeof(dbdata_wait) + MESSAGE_ID_LENGTH);
1569 host_record->count = host_record->sequence = 0;
1572 /* Compute the current length */
1574 host_length = host_record->count * MESSAGE_ID_LENGTH;
1576 /* Search the record to see if the current message is already in it. */
1578 for (s = host_record->text; s < host_record->text + host_length;
1579 s += MESSAGE_ID_LENGTH)
1581 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1582 { already = TRUE; break; }
1585 /* If we haven't found this message in the main record, search any
1586 continuation records that exist. */
1588 for (i = host_record->sequence - 1; i >= 0 && !already; i--)
1591 sprintf(CS buffer, "%.200s:%d", host->name, i);
1592 cont = dbfn_read(dbm_file, buffer);
1595 int clen = cont->count * MESSAGE_ID_LENGTH;
1596 for (s = cont->text; s < cont->text + clen; s += MESSAGE_ID_LENGTH)
1598 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1599 { already = TRUE; break; }
1604 /* If this message is already in a record, no need to update. */
1608 DEBUG(D_transport) debug_printf("already listed for %s\n", host->name);
1613 /* If this record is full, write it out with a new name constructed
1614 from the sequence number, increase the sequence number, and empty
1617 if (host_record->count >= WAIT_NAME_MAX)
1619 sprintf(CS buffer, "%.200s:%d", host->name, host_record->sequence);
1620 dbfn_write(dbm_file, buffer, host_record, sizeof(dbdata_wait) + host_length);
1621 host_record->sequence++;
1622 host_record->count = 0;
1626 /* If this record is not full, increase the size of the record to
1627 allow for one new message id. */
1632 store_get(sizeof(dbdata_wait) + host_length + MESSAGE_ID_LENGTH);
1633 memcpy(newr, host_record, sizeof(dbdata_wait) + host_length);
1637 /* Now add the new name on the end */
1639 memcpy(host_record->text + host_length, message_id, MESSAGE_ID_LENGTH);
1640 host_record->count++;
1641 host_length += MESSAGE_ID_LENGTH;
1643 /* Update the database */
1645 dbfn_write(dbm_file, host->name, host_record, sizeof(dbdata_wait) + host_length);
1646 DEBUG(D_transport) debug_printf("added to list for %s\n", host->name);
1651 dbfn_close(dbm_file);
1657 /*************************************************
1658 * Test for waiting messages *
1659 *************************************************/
1661 /* This function is called by a remote transport which uses the previous
1662 function to remember which messages are waiting for which remote hosts. It's
1663 called after a successful delivery and its job is to check whether there is
1664 another message waiting for the same host. However, it doesn't do this if the
1665 current continue sequence is greater than the maximum supplied as an argument,
1666 or greater than the global connection_max_messages, which, if set, overrides.
1669 transport_name name of the transport
1670 hostname name of the host
1671 local_message_max maximum number of messages down one connection
1672 as set by the caller transport
1673 new_message_id set to the message id of a waiting message
1674 more set TRUE if there are yet more messages waiting
1675 oicf_func function to call to validate if it is ok to send
1676 to this message_id from the current instance.
1677 oicf_data opaque data for oicf_func
1679 Returns: TRUE if new_message_id set; FALSE otherwise
1682 typedef struct msgq_s
1684 uschar message_id [MESSAGE_ID_LENGTH + 1];
1689 transport_check_waiting(const uschar *transport_name, const uschar *hostname,
1690 int local_message_max, uschar *new_message_id, BOOL *more, oicf oicf_func, void *oicf_data)
1692 dbdata_wait *host_record;
1699 struct stat statbuf;
1705 debug_printf("transport_check_waiting entered\n");
1706 debug_printf(" sequence=%d local_max=%d global_max=%d\n",
1707 continue_sequence, local_message_max, connection_max_messages);
1710 /* Do nothing if we have hit the maximum number that can be send down one
1713 if (connection_max_messages >= 0) local_message_max = connection_max_messages;
1714 if (local_message_max > 0 && continue_sequence >= local_message_max)
1717 debug_printf("max messages for one connection reached: returning\n");
1721 /* Open the waiting information database. */
1723 sprintf(CS buffer, "wait-%.200s", transport_name);
1724 dbm_file = dbfn_open(buffer, O_RDWR, &dbblock, TRUE);
1725 if (dbm_file == NULL) return FALSE;
1727 /* See if there is a record for this host; if not, there's nothing to do. */
1729 if (!(host_record = dbfn_read(dbm_file, hostname)))
1731 dbfn_close(dbm_file);
1732 DEBUG(D_transport) debug_printf("no messages waiting for %s\n", hostname);
1736 /* If the data in the record looks corrupt, just log something and
1737 don't try to use it. */
1739 if (host_record->count > WAIT_NAME_MAX)
1741 dbfn_close(dbm_file);
1742 log_write(0, LOG_MAIN|LOG_PANIC, "smtp-wait database entry for %s has bad "
1743 "count=%d (max=%d)", hostname, host_record->count, WAIT_NAME_MAX);
1747 /* Scan the message ids in the record from the end towards the beginning,
1748 until one is found for which a spool file actually exists. If the record gets
1749 emptied, delete it and continue with any continuation records that may exist.
1752 /* For Bug 1141, I refactored this major portion of the routine, it is risky
1753 but the 1 off will remain without it. This code now allows me to SKIP over
1754 a message I do not want to send out on this run. */
1756 host_length = host_record->count * MESSAGE_ID_LENGTH;
1762 int msgq_actual = 0;
1763 BOOL bFound = FALSE;
1764 BOOL bContinuation = FALSE;
1766 /* create an array to read entire message queue into memory for processing */
1768 msgq = (msgq_t*) malloc(sizeof(msgq_t) * host_record->count);
1769 msgq_count = host_record->count;
1770 msgq_actual = msgq_count;
1772 for (i = 0; i < host_record->count; ++i)
1774 msgq[i].bKeep = TRUE;
1776 Ustrncpy(msgq[i].message_id, host_record->text + (i * MESSAGE_ID_LENGTH),
1778 msgq[i].message_id[MESSAGE_ID_LENGTH] = 0;
1781 /* first thing remove current message id if it exists */
1783 for (i = 0; i < msgq_count; ++i)
1784 if (Ustrcmp(msgq[i].message_id, message_id) == 0)
1786 msgq[i].bKeep = FALSE;
1790 /* now find the next acceptable message_id */
1792 for (i = msgq_count - 1; i >= 0; --i) if (msgq[i].bKeep)
1796 subdir[0] = split_spool_directory ? msgq[i].message_id[5] : 0;
1799 if (Ustat(spool_fname(US"input", subdir, msgq[i].message_id, US"-D"),
1801 msgq[i].bKeep = FALSE;
1802 else if (!oicf_func || oicf_func(msgq[i].message_id, oicf_data))
1804 Ustrcpy(new_message_id, msgq[i].message_id);
1805 msgq[i].bKeep = FALSE;
1812 for (msgq_actual = 0, i = 0; i < msgq_count; ++i)
1816 /* reassemble the host record, based on removed message ids, from in
1819 if (msgq_actual <= 0)
1822 host_record->count = 0;
1826 host_length = msgq_actual * MESSAGE_ID_LENGTH;
1827 host_record->count = msgq_actual;
1829 if (msgq_actual < msgq_count)
1832 for (new_count = 0, i = 0; i < msgq_count; ++i)
1834 Ustrncpy(&host_record->text[new_count++ * MESSAGE_ID_LENGTH],
1835 msgq[i].message_id, MESSAGE_ID_LENGTH);
1837 host_record->text[new_count * MESSAGE_ID_LENGTH] = 0;
1841 /* Jeremy: check for a continuation record, this code I do not know how to
1842 test but the code should work */
1844 while (host_length <= 0)
1847 dbdata_wait * newr = NULL;
1849 /* Search for a continuation */
1851 for (i = host_record->sequence - 1; i >= 0 && !newr; i--)
1853 sprintf(CS buffer, "%.200s:%d", hostname, i);
1854 newr = dbfn_read(dbm_file, buffer);
1857 /* If no continuation, delete the current and break the loop */
1861 dbfn_delete(dbm_file, hostname);
1865 /* Else replace the current with the continuation */
1867 dbfn_delete(dbm_file, buffer);
1869 host_length = host_record->count * MESSAGE_ID_LENGTH;
1871 bContinuation = TRUE;
1874 if (bFound) /* Usual exit from main loop */
1880 /* If host_length <= 0 we have emptied a record and not found a good message,
1881 and there are no continuation records. Otherwise there is a continuation
1882 record to process. */
1884 if (host_length <= 0)
1886 dbfn_close(dbm_file);
1887 DEBUG(D_transport) debug_printf("waiting messages already delivered\n");
1891 /* we were not able to find an acceptable message, nor was there a
1892 * continuation record. So bug out, outer logic will clean this up.
1897 Ustrcpy(new_message_id, message_id);
1898 dbfn_close(dbm_file);
1903 } /* we need to process a continuation record */
1905 /* Control gets here when an existing message has been encountered; its
1906 id is in new_message_id, and host_length is the revised length of the
1907 host record. If it is zero, the record has been removed. Update the
1908 record if required, close the database, and return TRUE. */
1910 if (host_length > 0)
1912 host_record->count = host_length/MESSAGE_ID_LENGTH;
1914 dbfn_write(dbm_file, hostname, host_record, (int)sizeof(dbdata_wait) + host_length);
1918 dbfn_close(dbm_file);
1922 /*************************************************
1923 * Deliver waiting message down same socket *
1924 *************************************************/
1926 /* Fork a new exim process to deliver the message, and do a re-exec, both to
1927 get a clean delivery process, and to regain root privilege in cases where it
1928 has been given away.
1931 transport_name to pass to the new process
1934 id the new message to process
1935 socket_fd the connected socket
1937 Returns: FALSE if fork fails; TRUE otherwise
1941 transport_pass_socket(const uschar *transport_name, const uschar *hostname,
1942 const uschar *hostaddress, uschar *id, int socket_fd)
1947 DEBUG(D_transport) debug_printf("transport_pass_socket entered\n");
1949 if ((pid = fork()) == 0)
1952 const uschar **argv;
1954 /* Disconnect entirely from the parent process. If we are running in the
1955 test harness, wait for a bit to allow the previous process time to finish,
1956 write the log, etc., so that the output is always in the same order for
1957 automatic comparison. */
1959 if ((pid = fork()) != 0) _exit(EXIT_SUCCESS);
1960 if (running_in_test_harness) sleep(1);
1962 /* Set up the calling arguments; use the standard function for the basics,
1963 but we have a number of extras that may be added. */
1965 argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, &i, FALSE, 0);
1967 if (smtp_authenticated) argv[i++] = US"-MCA";
1969 if (smtp_peer_options & PEER_OFFERED_CHUNKING) argv[i++] = US"-MCK";
1970 if (smtp_peer_options & PEER_OFFERED_DSN) argv[i++] = US"-MCD";
1971 if (smtp_peer_options & PEER_OFFERED_PIPE) argv[i++] = US"-MCP";
1972 if (smtp_peer_options & PEER_OFFERED_SIZE) argv[i++] = US"-MCS";
1974 if (smtp_peer_options & PEER_OFFERED_TLS) argv[i++] = US"-MCT";
1977 if (queue_run_pid != (pid_t)0)
1979 argv[i++] = US"-MCQ";
1980 argv[i++] = string_sprintf("%d", queue_run_pid);
1981 argv[i++] = string_sprintf("%d", queue_run_pipe);
1984 argv[i++] = US"-MC";
1985 argv[i++] = US transport_name;
1986 argv[i++] = US hostname;
1987 argv[i++] = US hostaddress;
1988 argv[i++] = string_sprintf("%d", continue_sequence + 1);
1992 /* Arrange for the channel to be on stdin. */
1996 (void)dup2(socket_fd, 0);
1997 (void)close(socket_fd);
2000 DEBUG(D_exec) debug_print_argv(argv);
2001 exim_nullstd(); /* Ensure std{out,err} exist */
2002 execv(CS argv[0], (char *const *)argv);
2004 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
2005 _exit(errno); /* Note: must be _exit(), NOT exit() */
2008 /* If the process creation succeeded, wait for the first-level child, which
2009 immediately exits, leaving the second level process entirely disconnected from
2015 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
2016 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded\n");
2021 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
2029 /*************************************************
2030 * Set up direct (non-shell) command *
2031 *************************************************/
2033 /* This function is called when a command line is to be parsed and executed
2034 directly, without the use of /bin/sh. It is called by the pipe transport,
2035 the queryprogram router, and also from the main delivery code when setting up a
2036 transport filter process. The code for ETRN also makes use of this; in that
2037 case, no addresses are passed.
2040 argvptr pointer to anchor for argv vector
2041 cmd points to the command string (modified IN PLACE)
2042 expand_arguments true if expansion is to occur
2043 expand_failed error value to set if expansion fails; not relevant if
2045 addr chain of addresses, or NULL
2046 etext text for use in error messages
2047 errptr where to put error message if addr is NULL;
2048 otherwise it is put in the first address
2050 Returns: TRUE if all went well; otherwise an error will be
2051 set in the first address and FALSE returned
2055 transport_set_up_command(const uschar ***argvptr, uschar *cmd,
2056 BOOL expand_arguments, int expand_failed, address_item *addr,
2057 uschar *etext, uschar **errptr)
2060 const uschar **argv;
2062 int address_count = 0;
2066 /* Get store in which to build an argument list. Count the number of addresses
2067 supplied, and allow for that many arguments, plus an additional 60, which
2068 should be enough for anybody. Multiple addresses happen only when the local
2069 delivery batch option is set. */
2071 for (ad = addr; ad != NULL; ad = ad->next) address_count++;
2072 max_args = address_count + 60;
2073 *argvptr = argv = store_get((max_args+1)*sizeof(uschar *));
2075 /* Split the command up into arguments terminated by white space. Lose
2076 trailing space at the start and end. Double-quoted arguments can contain \\ and
2077 \" escapes and so can be handled by the standard function; single-quoted
2078 arguments are verbatim. Copy each argument into a new string. */
2081 while (isspace(*s)) s++;
2083 while (*s != 0 && argcount < max_args)
2088 while (*ss != 0 && *ss != '\'') ss++;
2089 argv[argcount++] = ss = store_get(ss - s++);
2090 while (*s != 0 && *s != '\'') *ss++ = *s++;
2094 else argv[argcount++] = string_copy(string_dequote(CUSS &s));
2095 while (isspace(*s)) s++;
2098 argv[argcount] = (uschar *)0;
2100 /* If *s != 0 we have run out of argument slots. */
2104 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
2108 addr->transport_return = FAIL;
2109 addr->message = msg;
2115 /* Expand each individual argument if required. Expansion happens for pipes set
2116 up in filter files and with directly-supplied commands. It does not happen if
2117 the pipe comes from a traditional .forward file. A failing expansion is a big
2118 disaster if the command came from Exim's configuration; if it came from a user
2119 it is just a normal failure. The expand_failed value is used as the error value
2120 to cater for these two cases.
2122 An argument consisting just of the text "$pipe_addresses" is treated specially.
2123 It is not passed to the general expansion function. Instead, it is replaced by
2124 a number of arguments, one for each address. This avoids problems with shell
2125 metacharacters and spaces in addresses.
2127 If the parent of the top address has an original part of "system-filter", this
2128 pipe was set up by the system filter, and we can permit the expansion of
2133 debug_printf("direct command:\n");
2134 for (i = 0; argv[i] != (uschar *)0; i++)
2135 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2138 if (expand_arguments)
2140 BOOL allow_dollar_recipients = addr != NULL &&
2141 addr->parent != NULL &&
2142 Ustrcmp(addr->parent->address, "system-filter") == 0;
2144 for (i = 0; argv[i] != (uschar *)0; i++)
2147 /* Handle special fudge for passing an address list */
2150 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
2151 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
2155 if (argcount + address_count - 1 > max_args)
2157 addr->transport_return = FAIL;
2158 addr->message = string_sprintf("Too many arguments to command \"%s\" "
2159 "in %s", cmd, etext);
2163 additional = address_count - 1;
2165 memmove(argv + i + 1 + additional, argv + i + 1,
2166 (argcount - i)*sizeof(uschar *));
2168 for (ad = addr; ad != NULL; ad = ad->next) {
2169 argv[i++] = ad->address;
2173 /* Subtract one since we replace $pipe_addresses */
2178 /* Handle special case of $address_pipe when af_force_command is set */
2180 else if (addr != NULL && testflag(addr,af_force_command) &&
2181 (Ustrcmp(argv[i], "$address_pipe") == 0 ||
2182 Ustrcmp(argv[i], "${address_pipe}") == 0))
2185 int address_pipe_argcount = 0;
2186 int address_pipe_max_args;
2187 uschar **address_pipe_argv;
2189 /* We can never have more then the argv we will be loading into */
2190 address_pipe_max_args = max_args - argcount + 1;
2193 debug_printf("address_pipe_max_args=%d\n", address_pipe_max_args);
2195 /* We allocate an additional for (uschar *)0 */
2196 address_pipe_argv = store_get((address_pipe_max_args+1)*sizeof(uschar *));
2198 /* +1 because addr->local_part[0] == '|' since af_force_command is set */
2199 s = expand_string(addr->local_part + 1);
2201 if (s == NULL || *s == '\0')
2203 addr->transport_return = FAIL;
2204 addr->message = string_sprintf("Expansion of \"%s\" "
2205 "from command \"%s\" in %s failed: %s",
2206 (addr->local_part + 1), cmd, etext, expand_string_message);
2210 while (isspace(*s)) s++; /* strip leading space */
2212 while (*s != 0 && address_pipe_argcount < address_pipe_max_args)
2217 while (*ss != 0 && *ss != '\'') ss++;
2218 address_pipe_argv[address_pipe_argcount++] = ss = store_get(ss - s++);
2219 while (*s != 0 && *s != '\'') *ss++ = *s++;
2223 else address_pipe_argv[address_pipe_argcount++] =
2224 string_copy(string_dequote(CUSS &s));
2225 while (isspace(*s)) s++; /* strip space after arg */
2228 address_pipe_argv[address_pipe_argcount] = (uschar *)0;
2230 /* If *s != 0 we have run out of argument slots. */
2233 uschar *msg = string_sprintf("Too many arguments in $address_pipe "
2234 "\"%s\" in %s", addr->local_part + 1, etext);
2237 addr->transport_return = FAIL;
2238 addr->message = msg;
2244 /* address_pipe_argcount - 1
2245 * because we are replacing $address_pipe in the argument list
2246 * with the first thing it expands to */
2247 if (argcount + address_pipe_argcount - 1 > max_args)
2249 addr->transport_return = FAIL;
2250 addr->message = string_sprintf("Too many arguments to command "
2251 "\"%s\" after expanding $address_pipe in %s", cmd, etext);
2255 /* If we are not just able to replace the slot that contained
2256 * $address_pipe (address_pipe_argcount == 1)
2257 * We have to move the existing argv by address_pipe_argcount - 1
2258 * Visually if address_pipe_argcount == 2:
2259 * [argv 0][argv 1][argv 2($address_pipe)][argv 3][0]
2260 * [argv 0][argv 1][ap_arg0][ap_arg1][old argv 3][0]
2262 if (address_pipe_argcount > 1)
2264 /* current position + additonal args */
2265 argv + i + address_pipe_argcount,
2266 /* current position + 1 (for the (uschar *)0 at the end) */
2268 /* -1 for the (uschar *)0 at the end)*/
2269 (argcount - i)*sizeof(uschar *)
2272 /* Now we fill in the slots we just moved argv out of
2273 * [argv 0][argv 1][argv 2=pipeargv[0]][argv 3=pipeargv[1]][old argv 3][0]
2275 for (address_pipe_i = 0;
2276 address_pipe_argv[address_pipe_i] != (uschar *)0;
2279 argv[i++] = address_pipe_argv[address_pipe_i];
2283 /* Subtract one since we replace $address_pipe */
2288 /* Handle normal expansion string */
2292 const uschar *expanded_arg;
2293 enable_dollar_recipients = allow_dollar_recipients;
2294 expanded_arg = expand_cstring(argv[i]);
2295 enable_dollar_recipients = FALSE;
2297 if (expanded_arg == NULL)
2299 uschar *msg = string_sprintf("Expansion of \"%s\" "
2300 "from command \"%s\" in %s failed: %s",
2301 argv[i], cmd, etext, expand_string_message);
2304 addr->transport_return = expand_failed;
2305 addr->message = msg;
2310 argv[i] = expanded_arg;
2316 debug_printf("direct command after expansion:\n");
2317 for (i = 0; argv[i] != (uschar *)0; i++)
2318 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2327 /* End of transport.c */