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 /* If CHUNKING, prefix with BDAT (size) NON-LAST. Also, reap responses
422 from previous SMTP commands. */
424 if (tctx && tctx->options & topt_use_bdat && tctx->chunk_cb)
425 if (tctx->chunk_cb(fd, tctx, (unsigned)len, tc_reap_prev|tc_reap_one) != OK)
428 if (!transport_write_block(fd, deliver_out_buffer, len))
430 chunk_ptr = deliver_out_buffer;
433 if ((ch = *ptr) == '\n')
435 int left = end - ptr - 1; /* count of chars left after NL */
437 /* Insert CR before NL if required */
439 if (tctx && tctx->options & topt_use_crlf) *chunk_ptr++ = '\r';
441 transport_newlines++;
443 /* The check_string test (formerly "from hack") replaces the specific
444 string at the start of a line with an escape string (e.g. "From " becomes
445 ">From " or "." becomes "..". It is a case-sensitive test. The length
446 check above ensures there is always enough room to insert this string. */
448 if (nl_check_length > 0)
450 if (left >= nl_check_length &&
451 Ustrncmp(ptr+1, nl_check, nl_check_length) == 0)
453 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
454 chunk_ptr += nl_escape_length;
455 ptr += nl_check_length;
458 /* Handle the case when there isn't enough left to match the whole
459 check string, but there may be a partial match. We remember how many
460 characters matched, and finish processing this chunk. */
462 else if (left <= 0) nl_partial_match = 0;
464 else if (Ustrncmp(ptr+1, nl_check, left) == 0)
466 nl_partial_match = left;
472 /* Not a NL character */
474 else *chunk_ptr++ = ch;
483 /*************************************************
484 * Generate address for RCPT TO *
485 *************************************************/
487 /* This function puts together an address for RCPT to, using the caseful
488 version of the local part and the caseful version of the domain. If there is no
489 prefix or suffix, or if affixes are to be retained, we can just use the
490 original address. Otherwise, if there is a prefix but no suffix we can use a
491 pointer into the original address. If there is a suffix, however, we have to
495 addr the address item
496 include_affixes TRUE if affixes are to be included
502 transport_rcpt_address(address_item *addr, BOOL include_affixes)
509 setflag(addr, af_include_affixes); /* Affects logged => line */
510 return addr->address;
513 if (addr->suffix == NULL)
515 if (addr->prefix == NULL) return addr->address;
516 return addr->address + Ustrlen(addr->prefix);
519 at = Ustrrchr(addr->address, '@');
520 plen = (addr->prefix == NULL)? 0 : Ustrlen(addr->prefix);
521 slen = Ustrlen(addr->suffix);
523 return string_sprintf("%.*s@%s", (at - addr->address - plen - slen),
524 addr->address + plen, at + 1);
528 /*************************************************
529 * Output Envelope-To: address & scan duplicates *
530 *************************************************/
532 /* This function is called from internal_transport_write_message() below, when
533 generating an Envelope-To: header line. It checks for duplicates of the given
534 address and its ancestors. When one is found, this function calls itself
535 recursively, to output the envelope address of the duplicate.
537 We want to avoid duplication in the list, which can arise for example when
538 A->B,C and then both B and C alias to D. This can also happen when there are
539 unseen drivers in use. So a list of addresses that have been output is kept in
542 It is also possible to have loops in the address ancestry/duplication graph,
543 for example if there are two top level addresses A and B and we have A->B,C and
544 B->A. To break the loop, we use a list of processed addresses in the dlist
547 After handling duplication, this function outputs the progenitor of the given
551 p the address we are interested in
552 pplist address of anchor of the list of addresses not to output
553 pdlist address of anchor of the list of processed addresses
554 first TRUE if this is the first address; set it FALSE afterwards
555 fd the file descriptor to write to
556 tctx transport context - processing to be done during output
558 Returns: FALSE if writing failed
562 write_env_to(address_item *p, struct aci **pplist, struct aci **pdlist,
563 BOOL *first, int fd, transport_ctx * tctx)
568 /* Do nothing if we have already handled this address. If not, remember it
569 so that we don't handle it again. */
571 for (ppp = *pdlist; ppp; ppp = ppp->next) if (p == ppp->ptr) return TRUE;
573 ppp = store_get(sizeof(struct aci));
578 /* Now scan up the ancestry, checking for duplicates at each generation. */
580 for (pp = p;; pp = pp->parent)
583 for (dup = addr_duplicate; dup; dup = dup->next)
584 if (dup->dupof == pp) /* a dup of our address */
585 if (!write_env_to(dup, pplist, pdlist, first, fd, tctx))
587 if (!pp->parent) break;
590 /* Check to see if we have already output the progenitor. */
592 for (ppp = *pplist; ppp; ppp = ppp->next) if (pp == ppp->ptr) break;
593 if (ppp) return TRUE;
595 /* Remember what we have output, and output it. */
597 ppp = store_get(sizeof(struct aci));
602 if (!*first && !write_chunk(fd, tctx, US",\n ", 3)) return FALSE;
604 return write_chunk(fd, tctx, pp->address, Ustrlen(pp->address));
610 /* Add/remove/rewwrite headers, and send them plus the empty-line sparator.
616 addr (chain of) addresses (for extra headers), or NULL;
617 only the first address is used
618 fd file descriptor to write the message to
619 sendfn function for output (transport or verify)
621 use_crlf turn NL into CR LF
622 use_bdat callback before chunk flush
623 rewrite_rules chain of header rewriting rules
624 rewrite_existflags flags for the rewriting rules
625 chunk_cb transport callback function for data-chunk commands
627 Returns: TRUE on success; FALSE on failure.
630 transport_headers_send(int fd, transport_ctx * tctx,
631 BOOL (*sendfn)(int fd, transport_ctx * tctx, uschar * s, int len))
635 transport_instance * tblock = tctx ? tctx->tblock : NULL;
636 address_item * addr = tctx ? tctx->addr : NULL;
638 /* Then the message's headers. Don't write any that are flagged as "old";
639 that means they were rewritten, or are a record of envelope rewriting, or
640 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
641 match any entries therein. It is a colon-sep list; expand the items
642 separately and squash any empty ones.
643 Then check addr->prop.remove_headers too, provided that addr is not NULL. */
645 for (h = header_list; h; h = h->next) if (h->type != htype_old)
648 BOOL include_header = TRUE;
650 list = tblock ? tblock->remove_headers : NULL;
651 for (i = 0; i < 2; i++) /* For remove_headers && addr->prop.remove_headers */
655 int sep = ':'; /* This is specified as a colon-separated list */
657 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
662 if (!(s = expand_string(s)) && !expand_string_forcedfail)
664 errno = ERRNO_CHHEADER_FAIL;
667 len = s ? Ustrlen(s) : 0;
668 if (strncmpic(h->text, s, len) != 0) continue;
670 while (*ss == ' ' || *ss == '\t') ss++;
671 if (*ss == ':') break;
673 if (s) { include_header = FALSE; break; }
675 if (addr) list = addr->prop.remove_headers;
678 /* If this header is to be output, try to rewrite it if there are rewriting
683 if (tblock && tblock->rewrite_rules)
685 void *reset_point = store_get(0);
688 if ((hh = rewrite_header(h, NULL, NULL, tblock->rewrite_rules,
689 tblock->rewrite_existflags, FALSE)))
691 if (!sendfn(fd, tctx, hh->text, hh->slen)) return FALSE;
692 store_reset(reset_point);
693 continue; /* With the next header line */
697 /* Either no rewriting rules, or it didn't get rewritten */
699 if (!sendfn(fd, tctx, h->text, h->slen)) return FALSE;
706 DEBUG(D_transport) debug_printf("removed header line:\n%s---\n", h->text);
710 /* Add on any address-specific headers. If there are multiple addresses,
711 they will all have the same headers in order to be batched. The headers
712 are chained in reverse order of adding (so several addresses from the
713 same alias might share some of them) but we want to output them in the
714 opposite order. This is a bit tedious, but there shouldn't be very many
715 of them. We just walk the list twice, reversing the pointers each time,
716 but on the second time, write out the items.
718 Headers added to an address by a router are guaranteed to end with a newline.
724 header_line *hprev = addr->prop.extra_headers;
726 for (i = 0; i < 2; i++)
727 for (h = hprev, hprev = NULL; h; h = hnext)
734 if (!sendfn(fd, tctx, h->text, h->slen)) return FALSE;
736 debug_printf("added header line(s):\n%s---\n", h->text);
741 /* If a string containing additional headers exists it is a newline-sep
742 list. Expand each item and write out the result. This is done last so that
743 if it (deliberately or accidentally) isn't in header format, it won't mess
744 up any other headers. An empty string or a forced expansion failure are
745 noops. An added header string from a transport may not end with a newline;
746 add one if it does not. */
748 if (tblock && (list = CUS tblock->add_headers))
753 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
754 if ((s = expand_string(s)))
756 int len = Ustrlen(s);
759 if (!sendfn(fd, tctx, s, len)) return FALSE;
760 if (s[len-1] != '\n' && !sendfn(fd, tctx, US"\n", 1))
764 debug_printf("added header line:\n%s", s);
765 if (s[len-1] != '\n') debug_printf("\n");
766 debug_printf("---\n");
770 else if (!expand_string_forcedfail)
771 { errno = ERRNO_CHHEADER_FAIL; return FALSE; }
774 /* Separate headers from body with a blank line */
776 return sendfn(fd, tctx, US"\n", 1);
780 /*************************************************
781 * Write the message *
782 *************************************************/
784 /* This function writes the message to the given file descriptor. The headers
785 are in the in-store data structure, and the rest of the message is in the open
786 file descriptor deliver_datafile. Make sure we start it at the beginning.
788 . If add_return_path is TRUE, a "return-path:" header is added to the message,
789 containing the envelope sender's address.
791 . If add_envelope_to is TRUE, a "envelope-to:" header is added to the message,
792 giving the top-level envelope address that caused this delivery to happen.
794 . If add_delivery_date is TRUE, a "delivery-date:" header is added to the
795 message. It gives the time and date that delivery took place.
797 . If check_string is not null, the start of each line is checked for that
798 string. If it is found, it is replaced by escape_string. This used to be
799 the "from hack" for files, and "smtp_dots" for escaping SMTP dots.
801 . If use_crlf is true, newlines are turned into CRLF (SMTP output).
803 The yield is TRUE if all went well, and FALSE if not. Exit *immediately* after
804 any writing or reading error, leaving the code in errno intact. Error exits
805 can include timeouts for certain transports, which are requested by setting
806 transport_write_timeout non-zero.
809 fd file descriptor to write the message to
811 addr (chain of) addresses (for extra headers), or NULL;
812 only the first address is used
813 tblock optional transport instance block (NULL signifies NULL/0):
814 add_headers a string containing one or more headers to add; it is
815 expanded, and must be in correct RFC 822 format as
816 it is transmitted verbatim; NULL => no additions,
817 and so does empty string or forced expansion fail
818 remove_headers a colon-separated list of headers to remove, or NULL
819 rewrite_rules chain of header rewriting rules
820 rewrite_existflags flags for the rewriting rules
821 options bit-wise options:
822 add_return_path if TRUE, add a "return-path" header
823 add_envelope_to if TRUE, add a "envelope-to" header
824 add_delivery_date if TRUE, add a "delivery-date" header
825 use_crlf if TRUE, turn NL into CR LF
826 end_dot if TRUE, send a terminating "." line at the end
827 no_headers if TRUE, omit the headers
828 no_body if TRUE, omit the body
829 size_limit if > 0, this is a limit to the size of message written;
830 it is used when returning messages to their senders,
831 and is approximate rather than exact, owing to chunk
833 check_string a string to check for at the start of lines, or NULL
834 escape_string a string to insert in front of any check string
836 Returns: TRUE on success; FALSE (with errno) on failure.
837 In addition, the global variable transport_count
838 is incremented by the number of bytes written.
842 internal_transport_write_message(int fd, transport_ctx * tctx, int size_limit)
846 /* Initialize pointer in output buffer. */
848 chunk_ptr = deliver_out_buffer;
850 /* Set up the data for start-of-line data checking and escaping */
852 nl_partial_match = -1;
853 if (tctx->check_string && tctx->escape_string)
855 nl_check = tctx->check_string;
856 nl_check_length = Ustrlen(nl_check);
857 nl_escape = tctx->escape_string;
858 nl_escape_length = Ustrlen(nl_escape);
861 nl_check_length = nl_escape_length = 0;
863 /* Whether the escaping mechanism is applied to headers or not is controlled by
864 an option (set for SMTP, not otherwise). Negate the length if not wanted till
865 after the headers. */
867 if (!(tctx->options & topt_escape_headers))
868 nl_check_length = -nl_check_length;
870 /* Write the headers if required, including any that have to be added. If there
871 are header rewriting rules, apply them. */
873 if (!(tctx->options & topt_no_headers))
875 /* Add return-path: if requested. */
877 if (tctx->options & topt_add_return_path)
879 uschar buffer[ADDRESS_MAXLENGTH + 20];
880 int n = sprintf(CS buffer, "Return-path: <%.*s>\n", ADDRESS_MAXLENGTH,
882 if (!write_chunk(fd, tctx, buffer, n)) return FALSE;
885 /* Add envelope-to: if requested */
887 if (tctx->options & topt_add_envelope_to)
891 struct aci *plist = NULL;
892 struct aci *dlist = NULL;
893 void *reset_point = store_get(0);
895 if (!write_chunk(fd, tctx, US"Envelope-to: ", 13)) return FALSE;
897 /* Pick up from all the addresses. The plist and dlist variables are
898 anchors for lists of addresses already handled; they have to be defined at
899 this level becuase write_env_to() calls itself recursively. */
901 for (p = tctx->addr; p; p = p->next)
902 if (!write_env_to(p, &plist, &dlist, &first, fd, tctx))
905 /* Add a final newline and reset the store used for tracking duplicates */
907 if (!write_chunk(fd, tctx, US"\n", 1)) return FALSE;
908 store_reset(reset_point);
911 /* Add delivery-date: if requested. */
913 if (tctx->options & topt_add_delivery_date)
916 int n = sprintf(CS buffer, "Delivery-date: %s\n", tod_stamp(tod_full));
917 if (!write_chunk(fd, tctx, buffer, n)) return FALSE;
920 /* Then the message's headers. Don't write any that are flagged as "old";
921 that means they were rewritten, or are a record of envelope rewriting, or
922 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
923 match any entries therein. Then check addr->prop.remove_headers too, provided that
926 if (!transport_headers_send(fd, tctx, &write_chunk))
930 /* When doing RFC3030 CHUNKING output, work out how much data will be in the
931 last BDAT, consisting of the current write_chunk() output buffer fill
932 (optimally, all of the headers - but it does not matter if we already had to
933 flush that buffer with non-last BDAT prependix) plus the amount of body data
934 (as expanded for CRLF lines). Then create and write the BDAT, and ensure
935 that further use of write_chunk() will not prepend BDATs.
936 The first BDAT written will also first flush any outstanding MAIL and RCPT
937 commands which were buffered thans to PIPELINING.
938 Commands go out (using a send()) from a different buffer to data (using a
939 write()). They might not end up in the same TCP segment, which is
942 if (tctx->options & topt_use_bdat)
947 if ((hsize = chunk_ptr - deliver_out_buffer) < 0)
949 if (!(tctx->options & topt_no_body))
951 if ((fsize = lseek(deliver_datafile, 0, SEEK_END)) < 0) return FALSE;
952 fsize -= SPOOL_DATA_START_OFFSET;
953 if (size_limit > 0 && fsize > size_limit)
955 size = hsize + fsize;
956 if (tctx->options & topt_use_crlf)
957 size += body_linecount; /* account for CRLF-expansion */
960 /* If the message is large, emit first a non-LAST chunk with just the
961 headers, and reap the command responses. This lets us error out early
962 on RCPT rejects rather than sending megabytes of data. Include headers
963 on the assumption they are cheap enough and some clever implementations
964 might errorcheck them too, on-the-fly, and reject that chunk. */
966 if (size > DELIVER_OUT_BUFFER_SIZE && hsize > 0)
968 if ( tctx->chunk_cb(fd, tctx, hsize, 0) != OK
969 || !transport_write_block(fd, deliver_out_buffer, hsize)
970 || tctx->chunk_cb(fd, tctx, 0, tc_reap_prev) != OK
973 chunk_ptr = deliver_out_buffer;
977 /* Emit a LAST datachunk command. */
979 if (tctx->chunk_cb(fd, tctx, size, tc_chunk_last) != OK)
982 tctx->options &= ~topt_use_bdat;
985 /* If the body is required, ensure that the data for check strings (formerly
986 the "from hack") is enabled by negating the length if necessary. (It will be
987 negative in cases where it isn't to apply to the headers). Then ensure the body
988 is positioned at the start of its file (following the message id), then write
989 it, applying the size limit if required. */
991 if (!(tctx->options & topt_no_body))
993 int size = size_limit;
995 nl_check_length = abs(nl_check_length);
996 nl_partial_match = 0;
997 if (lseek(deliver_datafile, SPOOL_DATA_START_OFFSET, SEEK_SET) < 0)
999 while ( (len = MAX(DELIVER_IN_BUFFER_SIZE, size)) > 0
1000 && (len = read(deliver_datafile, deliver_in_buffer, len)) > 0)
1002 if (!write_chunk(fd, tctx, deliver_in_buffer, len))
1007 /* A read error on the body will have left len == -1 and errno set. */
1009 if (len != 0) return FALSE;
1012 /* Finished with the check string */
1014 nl_check_length = nl_escape_length = 0;
1016 /* If requested, add a terminating "." line (SMTP output). */
1018 if (tctx->options & topt_end_dot && !write_chunk(fd, tctx, US".\n", 2))
1021 /* Write out any remaining data in the buffer before returning. */
1023 return (len = chunk_ptr - deliver_out_buffer) <= 0 ||
1024 transport_write_block(fd, deliver_out_buffer, len);
1028 #ifndef DISABLE_DKIM
1030 /***************************************************************************************************
1031 * External interface to write the message, while signing it with DKIM and/or Domainkeys *
1032 ***************************************************************************************************/
1034 /* This function is a wrapper around transport_write_message().
1035 It is only called from the smtp transport if DKIM or Domainkeys support
1036 is compiled in. The function sets up a replacement fd into a -K file,
1037 then calls the normal function. This way, the exact bits that exim would
1038 have put "on the wire" will end up in the file (except for TLS
1039 encapsulation, which is the very very last thing). When we are done
1040 signing the file, send the signed message down the original fd (or TLS fd).
1043 as for internal_transport_write_message() above, with additional arguments
1046 Returns: TRUE on success; FALSE (with errno) for any failure
1050 dkim_transport_write_message(int out_fd, transport_ctx * tctx,
1051 struct ob_dkim * dkim)
1056 uschar * dkim_spool_name;
1059 uschar *dkim_signature = NULL;
1064 /* If we can't sign, just call the original function. */
1066 if (!(dkim->dkim_private_key && dkim->dkim_domain && dkim->dkim_selector))
1067 return transport_write_message(out_fd, tctx, 0);
1069 dkim_spool_name = spool_fname(US"input", message_subdir, message_id,
1070 string_sprintf("-%d-K", (int)getpid()));
1072 if ((dkim_fd = Uopen(dkim_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE)) < 0)
1074 /* Can't create spool file. Ugh. */
1080 /* Call original function to write the -K file; does the CRLF expansion */
1082 options = tctx->options;
1083 tctx->options &= ~topt_use_bdat;
1084 rc = transport_write_message(dkim_fd, tctx, 0);
1085 tctx->options = options;
1087 /* Save error state. We must clean up before returning. */
1094 /* Rewind file and feed it to the goats^W DKIM lib */
1095 lseek(dkim_fd, 0, SEEK_SET);
1096 dkim_signature = dkim_exim_sign(dkim_fd,
1097 dkim->dkim_private_key,
1099 dkim->dkim_selector,
1101 dkim->dkim_sign_headers);
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_use_dsn) argv[i++] = US"-MCD";
1965 if (smtp_authenticated) argv[i++] = US"-MCA";
1968 if (tls_offered) argv[i++] = US"-MCT";
1971 if (smtp_use_size) argv[i++] = US"-MCS";
1972 if (smtp_use_pipelining) argv[i++] = US"-MCP";
1974 if (queue_run_pid != (pid_t)0)
1976 argv[i++] = US"-MCQ";
1977 argv[i++] = string_sprintf("%d", queue_run_pid);
1978 argv[i++] = string_sprintf("%d", queue_run_pipe);
1981 argv[i++] = US"-MC";
1982 argv[i++] = US transport_name;
1983 argv[i++] = US hostname;
1984 argv[i++] = US hostaddress;
1985 argv[i++] = string_sprintf("%d", continue_sequence + 1);
1989 /* Arrange for the channel to be on stdin. */
1993 (void)dup2(socket_fd, 0);
1994 (void)close(socket_fd);
1997 DEBUG(D_exec) debug_print_argv(argv);
1998 exim_nullstd(); /* Ensure std{out,err} exist */
1999 execv(CS argv[0], (char *const *)argv);
2001 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
2002 _exit(errno); /* Note: must be _exit(), NOT exit() */
2005 /* If the process creation succeeded, wait for the first-level child, which
2006 immediately exits, leaving the second level process entirely disconnected from
2012 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
2013 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded\n");
2018 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
2026 /*************************************************
2027 * Set up direct (non-shell) command *
2028 *************************************************/
2030 /* This function is called when a command line is to be parsed and executed
2031 directly, without the use of /bin/sh. It is called by the pipe transport,
2032 the queryprogram router, and also from the main delivery code when setting up a
2033 transport filter process. The code for ETRN also makes use of this; in that
2034 case, no addresses are passed.
2037 argvptr pointer to anchor for argv vector
2038 cmd points to the command string (modified IN PLACE)
2039 expand_arguments true if expansion is to occur
2040 expand_failed error value to set if expansion fails; not relevant if
2042 addr chain of addresses, or NULL
2043 etext text for use in error messages
2044 errptr where to put error message if addr is NULL;
2045 otherwise it is put in the first address
2047 Returns: TRUE if all went well; otherwise an error will be
2048 set in the first address and FALSE returned
2052 transport_set_up_command(const uschar ***argvptr, uschar *cmd,
2053 BOOL expand_arguments, int expand_failed, address_item *addr,
2054 uschar *etext, uschar **errptr)
2057 const uschar **argv;
2059 int address_count = 0;
2063 /* Get store in which to build an argument list. Count the number of addresses
2064 supplied, and allow for that many arguments, plus an additional 60, which
2065 should be enough for anybody. Multiple addresses happen only when the local
2066 delivery batch option is set. */
2068 for (ad = addr; ad != NULL; ad = ad->next) address_count++;
2069 max_args = address_count + 60;
2070 *argvptr = argv = store_get((max_args+1)*sizeof(uschar *));
2072 /* Split the command up into arguments terminated by white space. Lose
2073 trailing space at the start and end. Double-quoted arguments can contain \\ and
2074 \" escapes and so can be handled by the standard function; single-quoted
2075 arguments are verbatim. Copy each argument into a new string. */
2078 while (isspace(*s)) s++;
2080 while (*s != 0 && argcount < max_args)
2085 while (*ss != 0 && *ss != '\'') ss++;
2086 argv[argcount++] = ss = store_get(ss - s++);
2087 while (*s != 0 && *s != '\'') *ss++ = *s++;
2091 else argv[argcount++] = string_copy(string_dequote(CUSS &s));
2092 while (isspace(*s)) s++;
2095 argv[argcount] = (uschar *)0;
2097 /* If *s != 0 we have run out of argument slots. */
2101 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
2105 addr->transport_return = FAIL;
2106 addr->message = msg;
2112 /* Expand each individual argument if required. Expansion happens for pipes set
2113 up in filter files and with directly-supplied commands. It does not happen if
2114 the pipe comes from a traditional .forward file. A failing expansion is a big
2115 disaster if the command came from Exim's configuration; if it came from a user
2116 it is just a normal failure. The expand_failed value is used as the error value
2117 to cater for these two cases.
2119 An argument consisting just of the text "$pipe_addresses" is treated specially.
2120 It is not passed to the general expansion function. Instead, it is replaced by
2121 a number of arguments, one for each address. This avoids problems with shell
2122 metacharacters and spaces in addresses.
2124 If the parent of the top address has an original part of "system-filter", this
2125 pipe was set up by the system filter, and we can permit the expansion of
2130 debug_printf("direct command:\n");
2131 for (i = 0; argv[i] != (uschar *)0; i++)
2132 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2135 if (expand_arguments)
2137 BOOL allow_dollar_recipients = addr != NULL &&
2138 addr->parent != NULL &&
2139 Ustrcmp(addr->parent->address, "system-filter") == 0;
2141 for (i = 0; argv[i] != (uschar *)0; i++)
2144 /* Handle special fudge for passing an address list */
2147 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
2148 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
2152 if (argcount + address_count - 1 > max_args)
2154 addr->transport_return = FAIL;
2155 addr->message = string_sprintf("Too many arguments to command \"%s\" "
2156 "in %s", cmd, etext);
2160 additional = address_count - 1;
2162 memmove(argv + i + 1 + additional, argv + i + 1,
2163 (argcount - i)*sizeof(uschar *));
2165 for (ad = addr; ad != NULL; ad = ad->next) {
2166 argv[i++] = ad->address;
2170 /* Subtract one since we replace $pipe_addresses */
2175 /* Handle special case of $address_pipe when af_force_command is set */
2177 else if (addr != NULL && testflag(addr,af_force_command) &&
2178 (Ustrcmp(argv[i], "$address_pipe") == 0 ||
2179 Ustrcmp(argv[i], "${address_pipe}") == 0))
2182 int address_pipe_argcount = 0;
2183 int address_pipe_max_args;
2184 uschar **address_pipe_argv;
2186 /* We can never have more then the argv we will be loading into */
2187 address_pipe_max_args = max_args - argcount + 1;
2190 debug_printf("address_pipe_max_args=%d\n", address_pipe_max_args);
2192 /* We allocate an additional for (uschar *)0 */
2193 address_pipe_argv = store_get((address_pipe_max_args+1)*sizeof(uschar *));
2195 /* +1 because addr->local_part[0] == '|' since af_force_command is set */
2196 s = expand_string(addr->local_part + 1);
2198 if (s == NULL || *s == '\0')
2200 addr->transport_return = FAIL;
2201 addr->message = string_sprintf("Expansion of \"%s\" "
2202 "from command \"%s\" in %s failed: %s",
2203 (addr->local_part + 1), cmd, etext, expand_string_message);
2207 while (isspace(*s)) s++; /* strip leading space */
2209 while (*s != 0 && address_pipe_argcount < address_pipe_max_args)
2214 while (*ss != 0 && *ss != '\'') ss++;
2215 address_pipe_argv[address_pipe_argcount++] = ss = store_get(ss - s++);
2216 while (*s != 0 && *s != '\'') *ss++ = *s++;
2220 else address_pipe_argv[address_pipe_argcount++] =
2221 string_copy(string_dequote(CUSS &s));
2222 while (isspace(*s)) s++; /* strip space after arg */
2225 address_pipe_argv[address_pipe_argcount] = (uschar *)0;
2227 /* If *s != 0 we have run out of argument slots. */
2230 uschar *msg = string_sprintf("Too many arguments in $address_pipe "
2231 "\"%s\" in %s", addr->local_part + 1, etext);
2234 addr->transport_return = FAIL;
2235 addr->message = msg;
2241 /* address_pipe_argcount - 1
2242 * because we are replacing $address_pipe in the argument list
2243 * with the first thing it expands to */
2244 if (argcount + address_pipe_argcount - 1 > max_args)
2246 addr->transport_return = FAIL;
2247 addr->message = string_sprintf("Too many arguments to command "
2248 "\"%s\" after expanding $address_pipe in %s", cmd, etext);
2252 /* If we are not just able to replace the slot that contained
2253 * $address_pipe (address_pipe_argcount == 1)
2254 * We have to move the existing argv by address_pipe_argcount - 1
2255 * Visually if address_pipe_argcount == 2:
2256 * [argv 0][argv 1][argv 2($address_pipe)][argv 3][0]
2257 * [argv 0][argv 1][ap_arg0][ap_arg1][old argv 3][0]
2259 if (address_pipe_argcount > 1)
2261 /* current position + additonal args */
2262 argv + i + address_pipe_argcount,
2263 /* current position + 1 (for the (uschar *)0 at the end) */
2265 /* -1 for the (uschar *)0 at the end)*/
2266 (argcount - i)*sizeof(uschar *)
2269 /* Now we fill in the slots we just moved argv out of
2270 * [argv 0][argv 1][argv 2=pipeargv[0]][argv 3=pipeargv[1]][old argv 3][0]
2272 for (address_pipe_i = 0;
2273 address_pipe_argv[address_pipe_i] != (uschar *)0;
2276 argv[i++] = address_pipe_argv[address_pipe_i];
2280 /* Subtract one since we replace $address_pipe */
2285 /* Handle normal expansion string */
2289 const uschar *expanded_arg;
2290 enable_dollar_recipients = allow_dollar_recipients;
2291 expanded_arg = expand_cstring(argv[i]);
2292 enable_dollar_recipients = FALSE;
2294 if (expanded_arg == NULL)
2296 uschar *msg = string_sprintf("Expansion of \"%s\" "
2297 "from command \"%s\" in %s failed: %s",
2298 argv[i], cmd, etext, expand_string_message);
2301 addr->transport_return = expand_failed;
2302 addr->message = msg;
2307 argv[i] = expanded_arg;
2313 debug_printf("direct command after expansion:\n");
2314 for (i = 0; argv[i] != (uschar *)0; i++)
2315 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2324 /* End of transport.c */