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 = nelem(optionlist_transports);
115 readconf_options_transports(void)
117 struct transport_info * ti;
119 readconf_options_from_list(optionlist_transports, nelem(optionlist_transports), US"TRANSPORTS", NULL);
121 for (ti = transports_available; ti->driver_name[0]; ti++)
123 macro_create(string_sprintf("_DRIVER_TRANSPORT_%T", ti->driver_name), US"y", FALSE, TRUE);
124 readconf_options_from_list(ti->options, (unsigned)*ti->options_count, US"TRANSPORT", ti->driver_name);
128 /*************************************************
129 * Initialize transport list *
130 *************************************************/
132 /* Read the transports section of the configuration file, and set up a chain of
133 transport instances according to its contents. Each transport has generic
134 options and may also have its own private options. This function is only ever
135 called when transports == NULL. We use generic code in readconf to do most of
141 transport_instance *t;
143 readconf_driver_init(US"transport",
144 (driver_instance **)(&transports), /* chain anchor */
145 (driver_info *)transports_available, /* available drivers */
146 sizeof(transport_info), /* size of info block */
147 &transport_defaults, /* default values for generic options */
148 sizeof(transport_instance), /* size of instance block */
149 optionlist_transports, /* generic options */
150 optionlist_transports_size);
152 /* Now scan the configured transports and check inconsistencies. A shadow
153 transport is permitted only for local transports. */
155 for (t = transports; t; t = t->next)
157 if (!t->info->local && t->shadow)
158 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
159 "shadow transport not allowed on non-local transport %s", t->name);
161 if (t->body_only && t->headers_only)
162 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
163 "%s transport: body_only and headers_only are mutually exclusive",
170 /*************************************************
171 * Write block of data *
172 *************************************************/
174 /* Subroutine called by write_chunk() and at the end of the message actually
175 to write a data block. Also called directly by some transports to write
176 additional data to the file descriptor (e.g. prefix, suffix).
178 If a transport wants data transfers to be timed, it sets a non-zero value in
179 transport_write_timeout. A non-zero transport_write_timeout causes a timer to
180 be set for each block of data written from here. If time runs out, then write()
181 fails and provokes an error return. The caller can then inspect sigalrm_seen to
184 On some systems, if a quota is exceeded during the write, the yield is the
185 number of bytes written rather than an immediate error code. This also happens
186 on some systems in other cases, for example a pipe that goes away because the
187 other end's process terminates (Linux). On other systems, (e.g. Solaris 2) you
188 get the error codes the first time.
190 The write() function is also interruptible; the Solaris 2.6 man page says:
192 If write() is interrupted by a signal before it writes any
193 data, it will return -1 with errno set to EINTR.
195 If write() is interrupted by a signal after it successfully
196 writes some data, it will return the number of bytes written.
198 To handle these cases, we want to restart the write() to output the remainder
199 of the data after a non-negative return from write(), except after a timeout.
200 In the error cases (EDQUOT, EPIPE) no bytes get written the second time, and a
201 proper error then occurs. In principle, after an interruption, the second
202 write() could suffer the same fate, but we do not want to continue for
203 evermore, so stick a maximum repetition count on the loop to act as a
207 fd file descriptor to write to
208 block block of bytes to write
209 len number of bytes to write
211 Returns: TRUE on success, FALSE on failure (with errno preserved);
212 transport_count is incremented by the number of bytes written
216 transport_write_block(int fd, uschar *block, int len)
218 int i, rc, save_errno;
219 int local_timeout = transport_write_timeout;
221 /* This loop is for handling incomplete writes and other retries. In most
222 normal cases, it is only ever executed once. */
224 for (i = 0; i < 100; i++)
227 debug_printf("writing data block fd=%d size=%d timeout=%d\n",
228 fd, len, local_timeout);
230 /* This code makes use of alarm() in order to implement the timeout. This
231 isn't a very tidy way of doing things. Using non-blocking I/O with select()
232 provides a neater approach. However, I don't know how to do this when TLS is
235 if (transport_write_timeout <= 0) /* No timeout wanted */
238 if (tls_out.active == fd) rc = tls_write(FALSE, block, len); else
240 rc = write(fd, block, len);
244 /* Timeout wanted. */
248 alarm(local_timeout);
250 if (tls_out.active == fd)
251 rc = tls_write(FALSE, block, len);
254 rc = write(fd, block, len);
256 local_timeout = alarm(0);
264 /* Hopefully, the most common case is success, so test that first. */
266 if (rc == len) { transport_count += len; return TRUE; }
268 /* A non-negative return code is an incomplete write. Try again for the rest
269 of the block. If we have exactly hit the timeout, give up. */
275 transport_count += rc;
276 DEBUG(D_transport) debug_printf("write incomplete (%d)\n", rc);
277 goto CHECK_TIMEOUT; /* A few lines below */
280 /* A negative return code with an EINTR error is another form of
281 incomplete write, zero bytes having been written */
283 if (save_errno == EINTR)
286 debug_printf("write interrupted before anything written\n");
287 goto CHECK_TIMEOUT; /* A few lines below */
290 /* A response of EAGAIN from write() is likely only in the case of writing
291 to a FIFO that is not swallowing the data as fast as Exim is writing it. */
293 if (save_errno == EAGAIN)
296 debug_printf("write temporarily locked out, waiting 1 sec\n");
299 /* Before continuing to try another write, check that we haven't run out of
303 if (transport_write_timeout > 0 && local_timeout <= 0)
311 /* Otherwise there's been an error */
313 DEBUG(D_transport) debug_printf("writing error %d: %s\n", save_errno,
314 strerror(save_errno));
319 /* We've tried and tried and tried but still failed */
321 errno = ERRNO_WRITEINCOMPLETE;
328 /*************************************************
329 * Write formatted string *
330 *************************************************/
332 /* This is called by various transports. It is a convenience function.
337 ... arguments for format
339 Returns: the yield of transport_write_block()
343 transport_write_string(int fd, const char *format, ...)
346 va_start(ap, format);
347 if (!string_vformat(big_buffer, big_buffer_size, format, ap))
348 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong formatted string in transport");
350 return transport_write_block(fd, big_buffer, Ustrlen(big_buffer));
356 /*************************************************
357 * Write character chunk *
358 *************************************************/
360 /* Subroutine used by transport_write_message() to scan character chunks for
361 newlines and act appropriately. The object is to minimise the number of writes.
362 The output byte stream is buffered up in deliver_out_buffer, which is written
363 only when it gets full, thus minimizing write operations and TCP packets.
365 Static data is used to handle the case when the last character of the previous
366 chunk was NL, or matched part of the data that has to be escaped.
369 fd file descript to write to
370 chunk pointer to data to write
371 len length of data to write
372 tctx transport context - processing to be done during output
374 In addition, the static nl_xxx variables must be set as required.
376 Returns: TRUE on success, FALSE on failure (with errno preserved)
380 write_chunk(int fd, transport_ctx * tctx, uschar *chunk, int len)
382 uschar *start = chunk;
383 uschar *end = chunk + len;
385 int mlen = DELIVER_OUT_BUFFER_SIZE - nl_escape_length - 2;
387 /* The assumption is made that the check string will never stretch over move
388 than one chunk since the only time there are partial matches is when copying
389 the body in large buffers. There is always enough room in the buffer for an
390 escape string, since the loop below ensures this for each character it
391 processes, and it won't have stuck in the escape string if it left a partial
394 if (nl_partial_match >= 0)
396 if (nl_check_length > 0 && len >= nl_check_length &&
397 Ustrncmp(start, nl_check + nl_partial_match,
398 nl_check_length - nl_partial_match) == 0)
400 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
401 chunk_ptr += nl_escape_length;
402 start += nl_check_length - nl_partial_match;
405 /* The partial match was a false one. Insert the characters carried over
406 from the previous chunk. */
408 else if (nl_partial_match > 0)
410 Ustrncpy(chunk_ptr, nl_check, nl_partial_match);
411 chunk_ptr += nl_partial_match;
414 nl_partial_match = -1;
417 /* Now process the characters in the chunk. Whenever we hit a newline we check
418 for possible escaping. The code for the non-NL route should be as fast as
421 for (ptr = start; ptr < end; ptr++)
425 /* Flush the buffer if it has reached the threshold - we want to leave enough
426 room for the next uschar, plus a possible extra CR for an LF, plus the escape
429 if ((len = chunk_ptr - deliver_out_buffer) > mlen)
431 DEBUG(D_transport) debug_printf("flushing headers buffer\n");
433 /* If CHUNKING, prefix with BDAT (size) NON-LAST. Also, reap responses
434 from previous SMTP commands. */
436 if (tctx && tctx->options & topt_use_bdat && tctx->chunk_cb)
438 if ( tctx->chunk_cb(tctx, (unsigned)len, 0) != OK
439 || !transport_write_block(fd, deliver_out_buffer, len)
440 || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
445 if (!transport_write_block(fd, deliver_out_buffer, len))
447 chunk_ptr = deliver_out_buffer;
450 if ((ch = *ptr) == '\n')
452 int left = end - ptr - 1; /* count of chars left after NL */
454 /* Insert CR before NL if required */
456 if (tctx && tctx->options & topt_use_crlf) *chunk_ptr++ = '\r';
458 transport_newlines++;
460 /* The check_string test (formerly "from hack") replaces the specific
461 string at the start of a line with an escape string (e.g. "From " becomes
462 ">From " or "." becomes "..". It is a case-sensitive test. The length
463 check above ensures there is always enough room to insert this string. */
465 if (nl_check_length > 0)
467 if (left >= nl_check_length &&
468 Ustrncmp(ptr+1, nl_check, nl_check_length) == 0)
470 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
471 chunk_ptr += nl_escape_length;
472 ptr += nl_check_length;
475 /* Handle the case when there isn't enough left to match the whole
476 check string, but there may be a partial match. We remember how many
477 characters matched, and finish processing this chunk. */
479 else if (left <= 0) nl_partial_match = 0;
481 else if (Ustrncmp(ptr+1, nl_check, left) == 0)
483 nl_partial_match = left;
489 /* Not a NL character */
491 else *chunk_ptr++ = ch;
500 /*************************************************
501 * Generate address for RCPT TO *
502 *************************************************/
504 /* This function puts together an address for RCPT to, using the caseful
505 version of the local part and the caseful version of the domain. If there is no
506 prefix or suffix, or if affixes are to be retained, we can just use the
507 original address. Otherwise, if there is a prefix but no suffix we can use a
508 pointer into the original address. If there is a suffix, however, we have to
512 addr the address item
513 include_affixes TRUE if affixes are to be included
519 transport_rcpt_address(address_item *addr, BOOL include_affixes)
526 setflag(addr, af_include_affixes); /* Affects logged => line */
527 return addr->address;
530 if (addr->suffix == NULL)
532 if (addr->prefix == NULL) return addr->address;
533 return addr->address + Ustrlen(addr->prefix);
536 at = Ustrrchr(addr->address, '@');
537 plen = (addr->prefix == NULL)? 0 : Ustrlen(addr->prefix);
538 slen = Ustrlen(addr->suffix);
540 return string_sprintf("%.*s@%s", (at - addr->address - plen - slen),
541 addr->address + plen, at + 1);
545 /*************************************************
546 * Output Envelope-To: address & scan duplicates *
547 *************************************************/
549 /* This function is called from internal_transport_write_message() below, when
550 generating an Envelope-To: header line. It checks for duplicates of the given
551 address and its ancestors. When one is found, this function calls itself
552 recursively, to output the envelope address of the duplicate.
554 We want to avoid duplication in the list, which can arise for example when
555 A->B,C and then both B and C alias to D. This can also happen when there are
556 unseen drivers in use. So a list of addresses that have been output is kept in
559 It is also possible to have loops in the address ancestry/duplication graph,
560 for example if there are two top level addresses A and B and we have A->B,C and
561 B->A. To break the loop, we use a list of processed addresses in the dlist
564 After handling duplication, this function outputs the progenitor of the given
568 p the address we are interested in
569 pplist address of anchor of the list of addresses not to output
570 pdlist address of anchor of the list of processed addresses
571 first TRUE if this is the first address; set it FALSE afterwards
572 fd the file descriptor to write to
573 tctx transport context - processing to be done during output
575 Returns: FALSE if writing failed
579 write_env_to(address_item *p, struct aci **pplist, struct aci **pdlist,
580 BOOL *first, int fd, transport_ctx * tctx)
585 /* Do nothing if we have already handled this address. If not, remember it
586 so that we don't handle it again. */
588 for (ppp = *pdlist; ppp; ppp = ppp->next) if (p == ppp->ptr) return TRUE;
590 ppp = store_get(sizeof(struct aci));
595 /* Now scan up the ancestry, checking for duplicates at each generation. */
597 for (pp = p;; pp = pp->parent)
600 for (dup = addr_duplicate; dup; dup = dup->next)
601 if (dup->dupof == pp) /* a dup of our address */
602 if (!write_env_to(dup, pplist, pdlist, first, fd, tctx))
604 if (!pp->parent) break;
607 /* Check to see if we have already output the progenitor. */
609 for (ppp = *pplist; ppp; ppp = ppp->next) if (pp == ppp->ptr) break;
610 if (ppp) return TRUE;
612 /* Remember what we have output, and output it. */
614 ppp = store_get(sizeof(struct aci));
619 if (!*first && !write_chunk(fd, tctx, US",\n ", 3)) return FALSE;
621 return write_chunk(fd, tctx, pp->address, Ustrlen(pp->address));
627 /* Add/remove/rewrite headers, and send them plus the empty-line separator.
633 addr (chain of) addresses (for extra headers), or NULL;
634 only the first address is used
635 fd file descriptor to write the message to
636 tctx transport context
637 sendfn function for output (transport or verify)
639 Returns: TRUE on success; FALSE on failure.
642 transport_headers_send(int fd, transport_ctx * tctx,
643 BOOL (*sendfn)(int fd, transport_ctx * tctx, uschar * s, int len))
647 transport_instance * tblock = tctx ? tctx->tblock : NULL;
648 address_item * addr = tctx ? tctx->addr : NULL;
650 /* Then the message's headers. Don't write any that are flagged as "old";
651 that means they were rewritten, or are a record of envelope rewriting, or
652 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
653 match any entries therein. It is a colon-sep list; expand the items
654 separately and squash any empty ones.
655 Then check addr->prop.remove_headers too, provided that addr is not NULL. */
657 for (h = header_list; h; h = h->next) if (h->type != htype_old)
660 BOOL include_header = TRUE;
662 list = tblock ? tblock->remove_headers : NULL;
663 for (i = 0; i < 2; i++) /* For remove_headers && addr->prop.remove_headers */
667 int sep = ':'; /* This is specified as a colon-separated list */
669 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
674 if (!(s = expand_string(s)) && !expand_string_forcedfail)
676 errno = ERRNO_CHHEADER_FAIL;
679 len = s ? Ustrlen(s) : 0;
680 if (strncmpic(h->text, s, len) != 0) continue;
682 while (*ss == ' ' || *ss == '\t') ss++;
683 if (*ss == ':') break;
685 if (s) { include_header = FALSE; break; }
687 if (addr) list = addr->prop.remove_headers;
690 /* If this header is to be output, try to rewrite it if there are rewriting
695 if (tblock && tblock->rewrite_rules)
697 void *reset_point = store_get(0);
700 if ((hh = rewrite_header(h, NULL, NULL, tblock->rewrite_rules,
701 tblock->rewrite_existflags, FALSE)))
703 if (!sendfn(fd, tctx, hh->text, hh->slen)) return FALSE;
704 store_reset(reset_point);
705 continue; /* With the next header line */
709 /* Either no rewriting rules, or it didn't get rewritten */
711 if (!sendfn(fd, tctx, h->text, h->slen)) return FALSE;
718 DEBUG(D_transport) debug_printf("removed header line:\n%s---\n", h->text);
722 /* Add on any address-specific headers. If there are multiple addresses,
723 they will all have the same headers in order to be batched. The headers
724 are chained in reverse order of adding (so several addresses from the
725 same alias might share some of them) but we want to output them in the
726 opposite order. This is a bit tedious, but there shouldn't be very many
727 of them. We just walk the list twice, reversing the pointers each time,
728 but on the second time, write out the items.
730 Headers added to an address by a router are guaranteed to end with a newline.
736 header_line *hprev = addr->prop.extra_headers;
738 for (i = 0; i < 2; i++)
739 for (h = hprev, hprev = NULL; h; h = hnext)
746 if (!sendfn(fd, tctx, h->text, h->slen)) return FALSE;
748 debug_printf("added header line(s):\n%s---\n", h->text);
753 /* If a string containing additional headers exists it is a newline-sep
754 list. Expand each item and write out the result. This is done last so that
755 if it (deliberately or accidentally) isn't in header format, it won't mess
756 up any other headers. An empty string or a forced expansion failure are
757 noops. An added header string from a transport may not end with a newline;
758 add one if it does not. */
760 if (tblock && (list = CUS tblock->add_headers))
765 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
766 if ((s = expand_string(s)))
768 int len = Ustrlen(s);
771 if (!sendfn(fd, tctx, s, len)) return FALSE;
772 if (s[len-1] != '\n' && !sendfn(fd, tctx, US"\n", 1))
776 debug_printf("added header line:\n%s", s);
777 if (s[len-1] != '\n') debug_printf("\n");
778 debug_printf("---\n");
782 else if (!expand_string_forcedfail)
783 { errno = ERRNO_CHHEADER_FAIL; return FALSE; }
786 /* Separate headers from body with a blank line */
788 return sendfn(fd, tctx, US"\n", 1);
792 /*************************************************
793 * Write the message *
794 *************************************************/
796 /* This function writes the message to the given file descriptor. The headers
797 are in the in-store data structure, and the rest of the message is in the open
798 file descriptor deliver_datafile. Make sure we start it at the beginning.
800 . If add_return_path is TRUE, a "return-path:" header is added to the message,
801 containing the envelope sender's address.
803 . If add_envelope_to is TRUE, a "envelope-to:" header is added to the message,
804 giving the top-level envelope address that caused this delivery to happen.
806 . If add_delivery_date is TRUE, a "delivery-date:" header is added to the
807 message. It gives the time and date that delivery took place.
809 . If check_string is not null, the start of each line is checked for that
810 string. If it is found, it is replaced by escape_string. This used to be
811 the "from hack" for files, and "smtp_dots" for escaping SMTP dots.
813 . If use_crlf is true, newlines are turned into CRLF (SMTP output).
815 The yield is TRUE if all went well, and FALSE if not. Exit *immediately* after
816 any writing or reading error, leaving the code in errno intact. Error exits
817 can include timeouts for certain transports, which are requested by setting
818 transport_write_timeout non-zero.
821 fd file descriptor to write the message to
823 addr (chain of) addresses (for extra headers), or NULL;
824 only the first address is used
825 tblock optional transport instance block (NULL signifies NULL/0):
826 add_headers a string containing one or more headers to add; it is
827 expanded, and must be in correct RFC 822 format as
828 it is transmitted verbatim; NULL => no additions,
829 and so does empty string or forced expansion fail
830 remove_headers a colon-separated list of headers to remove, or NULL
831 rewrite_rules chain of header rewriting rules
832 rewrite_existflags flags for the rewriting rules
833 options bit-wise options:
834 add_return_path if TRUE, add a "return-path" header
835 add_envelope_to if TRUE, add a "envelope-to" header
836 add_delivery_date if TRUE, add a "delivery-date" header
837 use_crlf if TRUE, turn NL into CR LF
838 end_dot if TRUE, send a terminating "." line at the end
839 no_headers if TRUE, omit the headers
840 no_body if TRUE, omit the body
841 check_string a string to check for at the start of lines, or NULL
842 escape_string a string to insert in front of any check string
843 size_limit if > 0, this is a limit to the size of message written;
844 it is used when returning messages to their senders,
845 and is approximate rather than exact, owing to chunk
848 Returns: TRUE on success; FALSE (with errno) on failure.
849 In addition, the global variable transport_count
850 is incremented by the number of bytes written.
854 internal_transport_write_message(int fd, transport_ctx * tctx, int size_limit)
858 /* Initialize pointer in output buffer. */
860 chunk_ptr = deliver_out_buffer;
862 /* Set up the data for start-of-line data checking and escaping */
864 nl_partial_match = -1;
865 if (tctx->check_string && tctx->escape_string)
867 nl_check = tctx->check_string;
868 nl_check_length = Ustrlen(nl_check);
869 nl_escape = tctx->escape_string;
870 nl_escape_length = Ustrlen(nl_escape);
873 nl_check_length = nl_escape_length = 0;
875 /* Whether the escaping mechanism is applied to headers or not is controlled by
876 an option (set for SMTP, not otherwise). Negate the length if not wanted till
877 after the headers. */
879 if (!(tctx->options & topt_escape_headers))
880 nl_check_length = -nl_check_length;
882 /* Write the headers if required, including any that have to be added. If there
883 are header rewriting rules, apply them. */
885 if (!(tctx->options & topt_no_headers))
887 /* Add return-path: if requested. */
889 if (tctx->options & topt_add_return_path)
891 uschar buffer[ADDRESS_MAXLENGTH + 20];
892 int n = sprintf(CS buffer, "Return-path: <%.*s>\n", ADDRESS_MAXLENGTH,
894 if (!write_chunk(fd, tctx, buffer, n)) return FALSE;
897 /* Add envelope-to: if requested */
899 if (tctx->options & topt_add_envelope_to)
903 struct aci *plist = NULL;
904 struct aci *dlist = NULL;
905 void *reset_point = store_get(0);
907 if (!write_chunk(fd, tctx, US"Envelope-to: ", 13)) return FALSE;
909 /* Pick up from all the addresses. The plist and dlist variables are
910 anchors for lists of addresses already handled; they have to be defined at
911 this level because write_env_to() calls itself recursively. */
913 for (p = tctx->addr; p; p = p->next)
914 if (!write_env_to(p, &plist, &dlist, &first, fd, tctx))
917 /* Add a final newline and reset the store used for tracking duplicates */
919 if (!write_chunk(fd, tctx, US"\n", 1)) return FALSE;
920 store_reset(reset_point);
923 /* Add delivery-date: if requested. */
925 if (tctx->options & topt_add_delivery_date)
928 int n = sprintf(CS buffer, "Delivery-date: %s\n", tod_stamp(tod_full));
929 if (!write_chunk(fd, tctx, buffer, n)) return FALSE;
932 /* Then the message's headers. Don't write any that are flagged as "old";
933 that means they were rewritten, or are a record of envelope rewriting, or
934 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
935 match any entries therein. Then check addr->prop.remove_headers too, provided that
938 if (!transport_headers_send(fd, tctx, &write_chunk))
942 /* When doing RFC3030 CHUNKING output, work out how much data would be in a
943 last-BDAT, consisting of the current write_chunk() output buffer fill
944 (optimally, all of the headers - but it does not matter if we already had to
945 flush that buffer with non-last BDAT prependix) plus the amount of body data
946 (as expanded for CRLF lines). Then create and write BDAT(s), and ensure
947 that further use of write_chunk() will not prepend BDATs.
948 The first BDAT written will also first flush any outstanding MAIL and RCPT
949 commands which were buffered thans to PIPELINING.
950 Commands go out (using a send()) from a different buffer to data (using a
951 write()). They might not end up in the same TCP segment, which is
954 if (tctx->options & topt_use_bdat)
959 if ((hsize = chunk_ptr - deliver_out_buffer) < 0)
961 if (!(tctx->options & topt_no_body))
963 if ((fsize = lseek(deliver_datafile, 0, SEEK_END)) < 0) return FALSE;
964 fsize -= SPOOL_DATA_START_OFFSET;
965 if (size_limit > 0 && fsize > size_limit)
967 size = hsize + fsize;
968 if (tctx->options & topt_use_crlf)
969 size += body_linecount; /* account for CRLF-expansion */
972 /* If the message is large, emit first a non-LAST chunk with just the
973 headers, and reap the command responses. This lets us error out early
974 on RCPT rejects rather than sending megabytes of data. Include headers
975 on the assumption they are cheap enough and some clever implementations
976 might errorcheck them too, on-the-fly, and reject that chunk. */
978 if (size > DELIVER_OUT_BUFFER_SIZE && hsize > 0)
981 debug_printf("sending small initial BDAT; hsize=%d\n", hsize);
982 if ( tctx->chunk_cb(tctx, hsize, 0) != OK
983 || !transport_write_block(fd, deliver_out_buffer, hsize)
984 || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
987 chunk_ptr = deliver_out_buffer;
991 /* Emit a LAST datachunk command, and unmark the context for further
994 if (tctx->chunk_cb(tctx, size, tc_chunk_last) != OK)
996 tctx->options &= ~topt_use_bdat;
999 /* If the body is required, ensure that the data for check strings (formerly
1000 the "from hack") is enabled by negating the length if necessary. (It will be
1001 negative in cases where it isn't to apply to the headers). Then ensure the body
1002 is positioned at the start of its file (following the message id), then write
1003 it, applying the size limit if required. */
1005 if (!(tctx->options & topt_no_body))
1007 int size = size_limit;
1009 nl_check_length = abs(nl_check_length);
1010 nl_partial_match = 0;
1011 if (lseek(deliver_datafile, SPOOL_DATA_START_OFFSET, SEEK_SET) < 0)
1013 while ( (len = MAX(DELIVER_IN_BUFFER_SIZE, size)) > 0
1014 && (len = read(deliver_datafile, deliver_in_buffer, len)) > 0)
1016 if (!write_chunk(fd, tctx, deliver_in_buffer, len))
1021 /* A read error on the body will have left len == -1 and errno set. */
1023 if (len != 0) return FALSE;
1026 /* Finished with the check string */
1028 nl_check_length = nl_escape_length = 0;
1030 /* If requested, add a terminating "." line (SMTP output). */
1032 if (tctx->options & topt_end_dot && !write_chunk(fd, tctx, US".\n", 2))
1035 /* Write out any remaining data in the buffer before returning. */
1037 return (len = chunk_ptr - deliver_out_buffer) <= 0 ||
1038 transport_write_block(fd, deliver_out_buffer, len);
1042 #ifndef DISABLE_DKIM
1044 /***************************************************************************************************
1045 * External interface to write the message, while signing it with DKIM and/or Domainkeys *
1046 ***************************************************************************************************/
1048 /* This function is a wrapper around transport_write_message().
1049 It is only called from the smtp transport if DKIM or Domainkeys support
1050 is compiled in. The function sets up a replacement fd into a -K file,
1051 then calls the normal function. This way, the exact bits that exim would
1052 have put "on the wire" will end up in the file (except for TLS
1053 encapsulation, which is the very very last thing). When we are done
1054 signing the file, send the signed message down the original fd (or TLS fd).
1057 as for internal_transport_write_message() above, with additional arguments
1060 Returns: TRUE on success; FALSE (with errno) for any failure
1064 dkim_transport_write_message(int out_fd, transport_ctx * tctx,
1065 struct ob_dkim * dkim, const uschar ** err)
1070 uschar * dkim_spool_name;
1071 uschar * dkim_signature = NULL;
1072 int sread = 0, wwritten = 0, siglen = 0, options;
1074 const uschar * errstr;
1076 /* If we can't sign, just call the original function. */
1078 if (!(dkim->dkim_private_key && dkim->dkim_domain && dkim->dkim_selector))
1079 return transport_write_message(out_fd, tctx, 0);
1081 dkim_spool_name = spool_fname(US"input", message_subdir, message_id,
1082 string_sprintf("-%d-K", (int)getpid()));
1084 if ((dkim_fd = Uopen(dkim_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE)) < 0)
1086 /* Can't create spool file. Ugh. */
1089 *err = string_sprintf("dkim spoolfile create: %s", strerror(errno));
1093 /* Call original function to write the -K file; does the CRLF expansion
1094 (but, in the CHUNKING case, not dot-stuffing and dot-termination). */
1096 options = tctx->options;
1097 tctx->options &= ~topt_use_bdat;
1098 rc = transport_write_message(dkim_fd, tctx, 0);
1099 tctx->options = options;
1101 /* Save error state. We must clean up before returning. */
1108 /* Rewind file and feed it to the goats^W DKIM lib */
1109 dkim->dot_stuffed = !!(options & topt_end_dot);
1110 lseek(dkim_fd, 0, SEEK_SET);
1111 if ((dkim_signature = dkim_exim_sign(dkim_fd, dkim, &errstr)))
1112 siglen = Ustrlen(dkim_signature);
1113 else if (dkim->dkim_strict)
1115 uschar *dkim_strict_result = expand_string(dkim->dkim_strict);
1116 if (dkim_strict_result)
1117 if ( (strcmpic(dkim->dkim_strict,US"1") == 0) ||
1118 (strcmpic(dkim->dkim_strict,US"true") == 0) )
1120 /* Set errno to something halfway meaningful */
1121 save_errno = EACCES;
1122 log_write(0, LOG_MAIN, "DKIM: message could not be signed,"
1123 " and dkim_strict is set. Deferring message delivery.");
1130 #ifndef HAVE_LINUX_SENDFILE
1131 if (options & topt_use_bdat)
1133 k_file_size = lseek(dkim_fd, 0, SEEK_END); /* Fetch file size */
1135 if (options & topt_use_bdat)
1138 /* On big messages output a precursor chunk to get any pipelined
1139 MAIL & RCPT commands flushed, then reap the responses so we can
1140 error out on RCPT rejects before sending megabytes. */
1142 if (siglen + k_file_size > DELIVER_OUT_BUFFER_SIZE && siglen > 0)
1144 if ( tctx->chunk_cb(tctx, siglen, 0) != OK
1145 || !transport_write_block(out_fd, dkim_signature, siglen)
1146 || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
1152 /* Send the BDAT command for the entire message, as a single LAST-marked
1155 if (tctx->chunk_cb(tctx, siglen + k_file_size, tc_chunk_last) != OK)
1159 if(siglen > 0 && !transport_write_block(out_fd, dkim_signature, siglen))
1162 #ifdef HAVE_LINUX_SENDFILE
1163 /* We can use sendfile() to shove the file contents
1164 to the socket. However only if we don't use TLS,
1165 as then there's another layer of indirection
1166 before the data finally hits the socket. */
1167 if (tls_out.active != out_fd)
1173 lseek(dkim_fd, 0, SEEK_SET);
1175 while(copied >= 0 && offset < k_file_size)
1176 copied = sendfile(out_fd, dkim_fd, &offset, k_file_size - offset);
1186 lseek(dkim_fd, 0, SEEK_SET);
1188 /* Send file down the original fd */
1189 while((sread = read(dkim_fd, deliver_out_buffer, DELIVER_OUT_BUFFER_SIZE)) >0)
1191 uschar * p = deliver_out_buffer;
1192 /* write the chunk */
1197 wwritten = tls_out.active == out_fd
1198 ? tls_write(FALSE, p, sread)
1199 : write(out_fd, CS p, sread);
1201 wwritten = write(out_fd, CS p, sread);
1218 /* unlink -K file */
1219 (void)close(dkim_fd);
1220 Uunlink(dkim_spool_name);
1234 /*************************************************
1235 * External interface to write the message *
1236 *************************************************/
1238 /* If there is no filtering required, call the internal function above to do
1239 the real work, passing over all the arguments from this function. Otherwise,
1240 set up a filtering process, fork another process to call the internal function
1241 to write to the filter, and in this process just suck from the filter and write
1242 down the given fd. At the end, tidy up the pipes and the processes.
1244 Arguments: as for internal_transport_write_message() above
1246 Returns: TRUE on success; FALSE (with errno) for any failure
1247 transport_count is incremented by the number of bytes written
1251 transport_write_message(int fd, transport_ctx * tctx, int size_limit)
1253 BOOL last_filter_was_NL = TRUE;
1254 int rc, len, yield, fd_read, fd_write, save_errno;
1255 int pfd[2] = {-1, -1};
1256 pid_t filter_pid, write_pid;
1257 static transport_ctx dummy_tctx = {0};
1259 if (!tctx) tctx = &dummy_tctx;
1261 transport_filter_timed_out = FALSE;
1263 /* If there is no filter command set up, call the internal function that does
1264 the actual work, passing it the incoming fd, and return its result. */
1266 if ( !transport_filter_argv
1267 || !*transport_filter_argv
1268 || !**transport_filter_argv
1270 return internal_transport_write_message(fd, tctx, size_limit);
1272 /* Otherwise the message must be written to a filter process and read back
1273 before being written to the incoming fd. First set up the special processing to
1274 be done during the copying. */
1276 nl_partial_match = -1;
1278 if (tctx->check_string && tctx->escape_string)
1280 nl_check = tctx->check_string;
1281 nl_check_length = Ustrlen(nl_check);
1282 nl_escape = tctx->escape_string;
1283 nl_escape_length = Ustrlen(nl_escape);
1285 else nl_check_length = nl_escape_length = 0;
1287 /* Start up a subprocess to run the command. Ensure that our main fd will
1288 be closed when the subprocess execs, but remove the flag afterwards.
1289 (Otherwise, if this is a TCP/IP socket, it can't get passed on to another
1290 process to deliver another message.) We get back stdin/stdout file descriptors.
1291 If the process creation failed, give an error return. */
1297 write_pid = (pid_t)(-1);
1300 int bits = fcntl(fd, F_GETFD);
1301 (void)fcntl(fd, F_SETFD, bits | FD_CLOEXEC);
1302 filter_pid = child_open(USS transport_filter_argv, NULL, 077,
1303 &fd_write, &fd_read, FALSE);
1304 (void)fcntl(fd, F_SETFD, bits & ~FD_CLOEXEC);
1306 if (filter_pid < 0) goto TIDY_UP; /* errno set */
1309 debug_printf("process %d running as transport filter: fd_write=%d fd_read=%d\n",
1310 (int)filter_pid, fd_write, fd_read);
1312 /* Fork subprocess to write the message to the filter, and return the result
1313 via a(nother) pipe. While writing to the filter, we do not do the CRLF,
1314 smtp dots, or check string processing. */
1316 if (pipe(pfd) != 0) goto TIDY_UP; /* errno set */
1317 if ((write_pid = fork()) == 0)
1320 (void)close(fd_read);
1321 (void)close(pfd[pipe_read]);
1322 nl_check_length = nl_escape_length = 0;
1324 tctx->check_string = tctx->escape_string = NULL;
1325 tctx->options &= ~(topt_use_crlf | topt_end_dot | topt_use_bdat);
1327 rc = internal_transport_write_message(fd_write, tctx, size_limit);
1330 if ( write(pfd[pipe_write], (void *)&rc, sizeof(BOOL))
1332 || write(pfd[pipe_write], (void *)&save_errno, sizeof(int))
1334 || write(pfd[pipe_write], (void *)&tctx->addr->more_errno, sizeof(int))
1337 rc = FALSE; /* compiler quietening */
1342 /* Parent process: close our copy of the writing subprocess' pipes. */
1344 (void)close(pfd[pipe_write]);
1345 (void)close(fd_write);
1348 /* Writing process creation failed */
1352 errno = save_errno; /* restore */
1356 /* When testing, let the subprocess get going */
1358 if (running_in_test_harness) millisleep(250);
1361 debug_printf("process %d writing to transport filter\n", (int)write_pid);
1363 /* Copy the message from the filter to the output fd. A read error leaves len
1364 == -1 and errno set. We need to apply a timeout to the read, to cope with
1365 the case when the filter gets stuck, but it can be quite a long one. The
1366 default is 5m, but this is now configurable. */
1368 DEBUG(D_transport) debug_printf("copying from the filter\n");
1370 /* Copy the output of the filter, remembering if the last character was NL. If
1371 no data is returned, that counts as "ended with NL" (default setting of the
1372 variable is TRUE). */
1374 chunk_ptr = deliver_out_buffer;
1378 sigalrm_seen = FALSE;
1379 alarm(transport_filter_timeout);
1380 len = read(fd_read, deliver_in_buffer, DELIVER_IN_BUFFER_SIZE);
1385 transport_filter_timed_out = TRUE;
1389 /* If the read was successful, write the block down the original fd,
1390 remembering whether it ends in \n or not. */
1394 if (!write_chunk(fd, tctx, deliver_in_buffer, len)) goto TIDY_UP;
1395 last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
1398 /* Otherwise, break the loop. If we have hit EOF, set yield = TRUE. */
1402 if (len == 0) yield = TRUE;
1407 /* Tidying up code. If yield = FALSE there has been an error and errno is set
1408 to something. Ensure the pipes are all closed and the processes are removed. If
1409 there has been an error, kill the processes before waiting for them, just to be
1410 sure. Also apply a paranoia timeout. */
1415 (void)close(fd_read);
1416 if (fd_write > 0) (void)close(fd_write);
1420 if (filter_pid > 0) kill(filter_pid, SIGKILL);
1421 if (write_pid > 0) kill(write_pid, SIGKILL);
1424 /* Wait for the filter process to complete. */
1426 DEBUG(D_transport) debug_printf("waiting for filter process\n");
1427 if (filter_pid > 0 && (rc = child_close(filter_pid, 30)) != 0 && yield)
1430 save_errno = ERRNO_FILTER_FAIL;
1431 tctx->addr->more_errno = rc;
1432 DEBUG(D_transport) debug_printf("filter process returned %d\n", rc);
1435 /* Wait for the writing process to complete. If it ends successfully,
1436 read the results from its pipe, provided we haven't already had a filter
1439 DEBUG(D_transport) debug_printf("waiting for writing process\n");
1442 rc = child_close(write_pid, 30);
1447 if (read(pfd[pipe_read], (void *)&ok, sizeof(BOOL)) != sizeof(BOOL))
1450 debug_printf("pipe read from writing process: %s\n", strerror(errno));
1451 save_errno = ERRNO_FILTER_FAIL;
1456 int dummy = read(pfd[pipe_read], (void *)&save_errno, sizeof(int));
1457 dummy = read(pfd[pipe_read], (void *)&(tctx->addr->more_errno), sizeof(int));
1464 save_errno = ERRNO_FILTER_FAIL;
1465 tctx->addr->more_errno = rc;
1466 DEBUG(D_transport) debug_printf("writing process returned %d\n", rc);
1469 (void)close(pfd[pipe_read]);
1471 /* If there have been no problems we can now add the terminating "." if this is
1472 SMTP output, turning off escaping beforehand. If the last character from the
1473 filter was not NL, insert a NL to make the SMTP protocol work. */
1477 nl_check_length = nl_escape_length = 0;
1478 if ( tctx->options & topt_end_dot
1479 && ( last_filter_was_NL
1480 ? !write_chunk(fd, tctx, US".\n", 2)
1481 : !write_chunk(fd, tctx, US"\n.\n", 3)
1485 /* Write out any remaining data in the buffer. */
1488 yield = (len = chunk_ptr - deliver_out_buffer) <= 0
1489 || transport_write_block(fd, deliver_out_buffer, len);
1492 errno = save_errno; /* From some earlier error */
1496 debug_printf("end of filtering transport writing: yield=%d\n", yield);
1498 debug_printf("errno=%d more_errno=%d\n", errno, tctx->addr->more_errno);
1508 /*************************************************
1509 * Update waiting database *
1510 *************************************************/
1512 /* This is called when an address is deferred by remote transports that are
1513 capable of sending more than one message over one connection. A database is
1514 maintained for each transport, keeping track of which messages are waiting for
1515 which hosts. The transport can then consult this when eventually a successful
1516 delivery happens, and if it finds that another message is waiting for the same
1517 host, it can fire up a new process to deal with it using the same connection.
1519 The database records are keyed by host name. They can get full if there are
1520 lots of messages waiting, and so there is a continuation mechanism for them.
1522 Each record contains a list of message ids, packed end to end without any
1523 zeros. Each one is MESSAGE_ID_LENGTH bytes long. The count field says how many
1524 in this record, and the sequence field says if there are any other records for
1525 this host. If the sequence field is 0, there are none. If it is 1, then another
1526 record with the name <hostname>:0 exists; if it is 2, then two other records
1527 with sequence numbers 0 and 1 exist, and so on.
1529 Currently, an exhaustive search of all continuation records has to be done to
1530 determine whether to add a message id to a given record. This shouldn't be
1531 too bad except in extreme cases. I can't figure out a *simple* way of doing
1534 Old records should eventually get swept up by the exim_tidydb utility.
1537 hostlist list of hosts that this message could be sent to
1538 tpname name of the transport
1544 transport_update_waiting(host_item *hostlist, uschar *tpname)
1546 const uschar *prevname = US"";
1551 DEBUG(D_transport) debug_printf("updating wait-%s database\n", tpname);
1553 /* Open the database for this transport */
1555 if (!(dbm_file = dbfn_open(string_sprintf("wait-%.200s", tpname),
1556 O_RDWR, &dbblock, TRUE)))
1559 /* Scan the list of hosts for which this message is waiting, and ensure
1560 that the message id is in each host record. */
1562 for (host = hostlist; host; host = host->next)
1564 BOOL already = FALSE;
1565 dbdata_wait *host_record;
1570 /* Skip if this is the same host as we just processed; otherwise remember
1571 the name for next time. */
1573 if (Ustrcmp(prevname, host->name) == 0) continue;
1574 prevname = host->name;
1576 /* Look up the host record; if there isn't one, make an empty one. */
1578 if (!(host_record = dbfn_read(dbm_file, host->name)))
1580 host_record = store_get(sizeof(dbdata_wait) + MESSAGE_ID_LENGTH);
1581 host_record->count = host_record->sequence = 0;
1584 /* Compute the current length */
1586 host_length = host_record->count * MESSAGE_ID_LENGTH;
1588 /* Search the record to see if the current message is already in it. */
1590 for (s = host_record->text; s < host_record->text + host_length;
1591 s += MESSAGE_ID_LENGTH)
1592 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1593 { already = TRUE; break; }
1595 /* If we haven't found this message in the main record, search any
1596 continuation records that exist. */
1598 for (i = host_record->sequence - 1; i >= 0 && !already; i--)
1601 sprintf(CS buffer, "%.200s:%d", host->name, i);
1602 if ((cont = dbfn_read(dbm_file, buffer)))
1604 int clen = cont->count * MESSAGE_ID_LENGTH;
1605 for (s = cont->text; s < cont->text + clen; s += MESSAGE_ID_LENGTH)
1606 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1607 { already = TRUE; break; }
1611 /* If this message is already in a record, no need to update. */
1615 DEBUG(D_transport) debug_printf("already listed for %s\n", host->name);
1620 /* If this record is full, write it out with a new name constructed
1621 from the sequence number, increase the sequence number, and empty
1624 if (host_record->count >= WAIT_NAME_MAX)
1626 sprintf(CS buffer, "%.200s:%d", host->name, host_record->sequence);
1627 dbfn_write(dbm_file, buffer, host_record, sizeof(dbdata_wait) + host_length);
1628 host_record->sequence++;
1629 host_record->count = 0;
1633 /* If this record is not full, increase the size of the record to
1634 allow for one new message id. */
1639 store_get(sizeof(dbdata_wait) + host_length + MESSAGE_ID_LENGTH);
1640 memcpy(newr, host_record, sizeof(dbdata_wait) + host_length);
1644 /* Now add the new name on the end */
1646 memcpy(host_record->text + host_length, message_id, MESSAGE_ID_LENGTH);
1647 host_record->count++;
1648 host_length += MESSAGE_ID_LENGTH;
1650 /* Update the database */
1652 dbfn_write(dbm_file, host->name, host_record, sizeof(dbdata_wait) + host_length);
1653 DEBUG(D_transport) debug_printf("added to list for %s\n", host->name);
1658 dbfn_close(dbm_file);
1664 /*************************************************
1665 * Test for waiting messages *
1666 *************************************************/
1668 /* This function is called by a remote transport which uses the previous
1669 function to remember which messages are waiting for which remote hosts. It's
1670 called after a successful delivery and its job is to check whether there is
1671 another message waiting for the same host. However, it doesn't do this if the
1672 current continue sequence is greater than the maximum supplied as an argument,
1673 or greater than the global connection_max_messages, which, if set, overrides.
1676 transport_name name of the transport
1677 hostname name of the host
1678 local_message_max maximum number of messages down one connection
1679 as set by the caller transport
1680 new_message_id set to the message id of a waiting message
1681 more set TRUE if there are yet more messages waiting
1682 oicf_func function to call to validate if it is ok to send
1683 to this message_id from the current instance.
1684 oicf_data opaque data for oicf_func
1686 Returns: TRUE if new_message_id set; FALSE otherwise
1689 typedef struct msgq_s
1691 uschar message_id [MESSAGE_ID_LENGTH + 1];
1696 transport_check_waiting(const uschar *transport_name, const uschar *hostname,
1697 int local_message_max, uschar *new_message_id, BOOL *more, oicf oicf_func, void *oicf_data)
1699 dbdata_wait *host_record;
1705 struct stat statbuf;
1711 debug_printf("transport_check_waiting entered\n");
1712 debug_printf(" sequence=%d local_max=%d global_max=%d\n",
1713 continue_sequence, local_message_max, connection_max_messages);
1716 /* Do nothing if we have hit the maximum number that can be send down one
1719 if (connection_max_messages >= 0) local_message_max = connection_max_messages;
1720 if (local_message_max > 0 && continue_sequence >= local_message_max)
1723 debug_printf("max messages for one connection reached: returning\n");
1727 /* Open the waiting information database. */
1729 if (!(dbm_file = dbfn_open(string_sprintf("wait-%.200s", transport_name),
1730 O_RDWR, &dbblock, TRUE)))
1733 /* See if there is a record for this host; if not, there's nothing to do. */
1735 if (!(host_record = dbfn_read(dbm_file, hostname)))
1737 dbfn_close(dbm_file);
1738 DEBUG(D_transport) debug_printf("no messages waiting for %s\n", hostname);
1742 /* If the data in the record looks corrupt, just log something and
1743 don't try to use it. */
1745 if (host_record->count > WAIT_NAME_MAX)
1747 dbfn_close(dbm_file);
1748 log_write(0, LOG_MAIN|LOG_PANIC, "smtp-wait database entry for %s has bad "
1749 "count=%d (max=%d)", hostname, host_record->count, WAIT_NAME_MAX);
1753 /* Scan the message ids in the record from the end towards the beginning,
1754 until one is found for which a spool file actually exists. If the record gets
1755 emptied, delete it and continue with any continuation records that may exist.
1758 /* For Bug 1141, I refactored this major portion of the routine, it is risky
1759 but the 1 off will remain without it. This code now allows me to SKIP over
1760 a message I do not want to send out on this run. */
1762 host_length = host_record->count * MESSAGE_ID_LENGTH;
1768 int msgq_actual = 0;
1769 BOOL bFound = FALSE;
1770 BOOL bContinuation = FALSE;
1772 /* create an array to read entire message queue into memory for processing */
1774 msgq = store_malloc(sizeof(msgq_t) * host_record->count);
1775 msgq_count = host_record->count;
1776 msgq_actual = msgq_count;
1778 for (i = 0; i < host_record->count; ++i)
1780 msgq[i].bKeep = TRUE;
1782 Ustrncpy(msgq[i].message_id, host_record->text + (i * MESSAGE_ID_LENGTH),
1784 msgq[i].message_id[MESSAGE_ID_LENGTH] = 0;
1787 /* first thing remove current message id if it exists */
1789 for (i = 0; i < msgq_count; ++i)
1790 if (Ustrcmp(msgq[i].message_id, message_id) == 0)
1792 msgq[i].bKeep = FALSE;
1796 /* now find the next acceptable message_id */
1798 for (i = msgq_count - 1; i >= 0; --i) if (msgq[i].bKeep)
1802 subdir[0] = split_spool_directory ? msgq[i].message_id[5] : 0;
1805 if (Ustat(spool_fname(US"input", subdir, msgq[i].message_id, US"-D"),
1807 msgq[i].bKeep = FALSE;
1808 else if (!oicf_func || oicf_func(msgq[i].message_id, oicf_data))
1810 Ustrcpy(new_message_id, msgq[i].message_id);
1811 msgq[i].bKeep = FALSE;
1818 for (msgq_actual = 0, i = 0; i < msgq_count; ++i)
1822 /* reassemble the host record, based on removed message ids, from in
1825 if (msgq_actual <= 0)
1828 host_record->count = 0;
1832 host_length = msgq_actual * MESSAGE_ID_LENGTH;
1833 host_record->count = msgq_actual;
1835 if (msgq_actual < msgq_count)
1838 for (new_count = 0, i = 0; i < msgq_count; ++i)
1840 Ustrncpy(&host_record->text[new_count++ * MESSAGE_ID_LENGTH],
1841 msgq[i].message_id, MESSAGE_ID_LENGTH);
1843 host_record->text[new_count * MESSAGE_ID_LENGTH] = 0;
1847 /* Check for a continuation record. */
1849 while (host_length <= 0)
1852 dbdata_wait * newr = NULL;
1855 /* Search for a continuation */
1857 for (i = host_record->sequence - 1; i >= 0 && !newr; i--)
1859 sprintf(CS buffer, "%.200s:%d", hostname, i);
1860 newr = dbfn_read(dbm_file, buffer);
1863 /* If no continuation, delete the current and break the loop */
1867 dbfn_delete(dbm_file, hostname);
1871 /* Else replace the current with the continuation */
1873 dbfn_delete(dbm_file, buffer);
1875 host_length = host_record->count * MESSAGE_ID_LENGTH;
1877 bContinuation = TRUE;
1880 if (bFound) /* Usual exit from main loop */
1886 /* If host_length <= 0 we have emptied a record and not found a good message,
1887 and there are no continuation records. Otherwise there is a continuation
1888 record to process. */
1890 if (host_length <= 0)
1892 dbfn_close(dbm_file);
1893 DEBUG(D_transport) debug_printf("waiting messages already delivered\n");
1897 /* we were not able to find an acceptable message, nor was there a
1898 * continuation record. So bug out, outer logic will clean this up.
1903 Ustrcpy(new_message_id, message_id);
1904 dbfn_close(dbm_file);
1909 } /* we need to process a continuation record */
1911 /* Control gets here when an existing message has been encountered; its
1912 id is in new_message_id, and host_length is the revised length of the
1913 host record. If it is zero, the record has been removed. Update the
1914 record if required, close the database, and return TRUE. */
1916 if (host_length > 0)
1918 host_record->count = host_length/MESSAGE_ID_LENGTH;
1920 dbfn_write(dbm_file, hostname, host_record, (int)sizeof(dbdata_wait) + host_length);
1924 dbfn_close(dbm_file);
1928 /*************************************************
1929 * Deliver waiting message down same socket *
1930 *************************************************/
1932 /* Just the regain-root-privilege exec portion */
1934 transport_do_pass_socket(const uschar *transport_name, const uschar *hostname,
1935 const uschar *hostaddress, uschar *id, int socket_fd)
1940 const uschar **argv;
1942 /* Set up the calling arguments; use the standard function for the basics,
1943 but we have a number of extras that may be added. */
1945 argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, &i, FALSE, 0);
1947 if (smtp_authenticated) argv[i++] = US"-MCA";
1948 if (smtp_peer_options & PEER_OFFERED_CHUNKING) argv[i++] = US"-MCK";
1949 if (smtp_peer_options & PEER_OFFERED_DSN) argv[i++] = US"-MCD";
1950 if (smtp_peer_options & PEER_OFFERED_PIPE) argv[i++] = US"-MCP";
1951 if (smtp_peer_options & PEER_OFFERED_SIZE) argv[i++] = US"-MCS";
1953 if (smtp_peer_options & PEER_OFFERED_TLS)
1954 if (tls_out.active >= 0 || continue_proxy_cipher)
1956 argv[i++] = US"-MCt";
1957 argv[i++] = sending_ip_address;
1958 argv[i++] = string_sprintf("%d", sending_port);
1959 argv[i++] = tls_out.active >= 0 ? tls_out.cipher : continue_proxy_cipher;
1962 argv[i++] = US"-MCT";
1965 if (queue_run_pid != (pid_t)0)
1967 argv[i++] = US"-MCQ";
1968 argv[i++] = string_sprintf("%d", queue_run_pid);
1969 argv[i++] = string_sprintf("%d", queue_run_pipe);
1972 argv[i++] = US"-MC";
1973 argv[i++] = US transport_name;
1974 argv[i++] = US hostname;
1975 argv[i++] = US hostaddress;
1976 argv[i++] = string_sprintf("%d", continue_sequence + 1);
1980 /* Arrange for the channel to be on stdin. */
1984 (void)dup2(socket_fd, 0);
1985 (void)close(socket_fd);
1988 DEBUG(D_exec) debug_print_argv(argv);
1989 exim_nullstd(); /* Ensure std{out,err} exist */
1990 execv(CS argv[0], (char *const *)argv);
1992 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
1993 _exit(errno); /* Note: must be _exit(), NOT exit() */
1998 /* Fork a new exim process to deliver the message, and do a re-exec, both to
1999 get a clean delivery process, and to regain root privilege in cases where it
2000 has been given away.
2003 transport_name to pass to the new process
2006 id the new message to process
2007 socket_fd the connected socket
2009 Returns: FALSE if fork fails; TRUE otherwise
2013 transport_pass_socket(const uschar *transport_name, const uschar *hostname,
2014 const uschar *hostaddress, uschar *id, int socket_fd)
2019 DEBUG(D_transport) debug_printf("transport_pass_socket entered\n");
2021 if ((pid = fork()) == 0)
2023 /* Disconnect entirely from the parent process. If we are running in the
2024 test harness, wait for a bit to allow the previous process time to finish,
2025 write the log, etc., so that the output is always in the same order for
2026 automatic comparison. */
2028 if ((pid = fork()) != 0) _exit(EXIT_SUCCESS);
2029 if (running_in_test_harness) sleep(1);
2031 transport_do_pass_socket(transport_name, hostname, hostaddress,
2035 /* If the process creation succeeded, wait for the first-level child, which
2036 immediately exits, leaving the second level process entirely disconnected from
2042 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
2043 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded\n");
2048 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
2056 /*************************************************
2057 * Set up direct (non-shell) command *
2058 *************************************************/
2060 /* This function is called when a command line is to be parsed and executed
2061 directly, without the use of /bin/sh. It is called by the pipe transport,
2062 the queryprogram router, and also from the main delivery code when setting up a
2063 transport filter process. The code for ETRN also makes use of this; in that
2064 case, no addresses are passed.
2067 argvptr pointer to anchor for argv vector
2068 cmd points to the command string (modified IN PLACE)
2069 expand_arguments true if expansion is to occur
2070 expand_failed error value to set if expansion fails; not relevant if
2072 addr chain of addresses, or NULL
2073 etext text for use in error messages
2074 errptr where to put error message if addr is NULL;
2075 otherwise it is put in the first address
2077 Returns: TRUE if all went well; otherwise an error will be
2078 set in the first address and FALSE returned
2082 transport_set_up_command(const uschar ***argvptr, uschar *cmd,
2083 BOOL expand_arguments, int expand_failed, address_item *addr,
2084 uschar *etext, uschar **errptr)
2087 const uschar **argv;
2089 int address_count = 0;
2093 /* Get store in which to build an argument list. Count the number of addresses
2094 supplied, and allow for that many arguments, plus an additional 60, which
2095 should be enough for anybody. Multiple addresses happen only when the local
2096 delivery batch option is set. */
2098 for (ad = addr; ad != NULL; ad = ad->next) address_count++;
2099 max_args = address_count + 60;
2100 *argvptr = argv = store_get((max_args+1)*sizeof(uschar *));
2102 /* Split the command up into arguments terminated by white space. Lose
2103 trailing space at the start and end. Double-quoted arguments can contain \\ and
2104 \" escapes and so can be handled by the standard function; single-quoted
2105 arguments are verbatim. Copy each argument into a new string. */
2108 while (isspace(*s)) s++;
2110 while (*s != 0 && argcount < max_args)
2115 while (*ss != 0 && *ss != '\'') ss++;
2116 argv[argcount++] = ss = store_get(ss - s++);
2117 while (*s != 0 && *s != '\'') *ss++ = *s++;
2121 else argv[argcount++] = string_copy(string_dequote(CUSS &s));
2122 while (isspace(*s)) s++;
2125 argv[argcount] = (uschar *)0;
2127 /* If *s != 0 we have run out of argument slots. */
2131 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
2135 addr->transport_return = FAIL;
2136 addr->message = msg;
2142 /* Expand each individual argument if required. Expansion happens for pipes set
2143 up in filter files and with directly-supplied commands. It does not happen if
2144 the pipe comes from a traditional .forward file. A failing expansion is a big
2145 disaster if the command came from Exim's configuration; if it came from a user
2146 it is just a normal failure. The expand_failed value is used as the error value
2147 to cater for these two cases.
2149 An argument consisting just of the text "$pipe_addresses" is treated specially.
2150 It is not passed to the general expansion function. Instead, it is replaced by
2151 a number of arguments, one for each address. This avoids problems with shell
2152 metacharacters and spaces in addresses.
2154 If the parent of the top address has an original part of "system-filter", this
2155 pipe was set up by the system filter, and we can permit the expansion of
2160 debug_printf("direct command:\n");
2161 for (i = 0; argv[i] != (uschar *)0; i++)
2162 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2165 if (expand_arguments)
2167 BOOL allow_dollar_recipients = addr != NULL &&
2168 addr->parent != NULL &&
2169 Ustrcmp(addr->parent->address, "system-filter") == 0;
2171 for (i = 0; argv[i] != (uschar *)0; i++)
2174 /* Handle special fudge for passing an address list */
2177 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
2178 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
2182 if (argcount + address_count - 1 > max_args)
2184 addr->transport_return = FAIL;
2185 addr->message = string_sprintf("Too many arguments to command \"%s\" "
2186 "in %s", cmd, etext);
2190 additional = address_count - 1;
2192 memmove(argv + i + 1 + additional, argv + i + 1,
2193 (argcount - i)*sizeof(uschar *));
2195 for (ad = addr; ad != NULL; ad = ad->next) {
2196 argv[i++] = ad->address;
2200 /* Subtract one since we replace $pipe_addresses */
2205 /* Handle special case of $address_pipe when af_force_command is set */
2207 else if (addr != NULL && testflag(addr,af_force_command) &&
2208 (Ustrcmp(argv[i], "$address_pipe") == 0 ||
2209 Ustrcmp(argv[i], "${address_pipe}") == 0))
2212 int address_pipe_argcount = 0;
2213 int address_pipe_max_args;
2214 uschar **address_pipe_argv;
2216 /* We can never have more then the argv we will be loading into */
2217 address_pipe_max_args = max_args - argcount + 1;
2220 debug_printf("address_pipe_max_args=%d\n", address_pipe_max_args);
2222 /* We allocate an additional for (uschar *)0 */
2223 address_pipe_argv = store_get((address_pipe_max_args+1)*sizeof(uschar *));
2225 /* +1 because addr->local_part[0] == '|' since af_force_command is set */
2226 s = expand_string(addr->local_part + 1);
2228 if (s == NULL || *s == '\0')
2230 addr->transport_return = FAIL;
2231 addr->message = string_sprintf("Expansion of \"%s\" "
2232 "from command \"%s\" in %s failed: %s",
2233 (addr->local_part + 1), cmd, etext, expand_string_message);
2237 while (isspace(*s)) s++; /* strip leading space */
2239 while (*s != 0 && address_pipe_argcount < address_pipe_max_args)
2244 while (*ss != 0 && *ss != '\'') ss++;
2245 address_pipe_argv[address_pipe_argcount++] = ss = store_get(ss - s++);
2246 while (*s != 0 && *s != '\'') *ss++ = *s++;
2250 else address_pipe_argv[address_pipe_argcount++] =
2251 string_copy(string_dequote(CUSS &s));
2252 while (isspace(*s)) s++; /* strip space after arg */
2255 address_pipe_argv[address_pipe_argcount] = (uschar *)0;
2257 /* If *s != 0 we have run out of argument slots. */
2260 uschar *msg = string_sprintf("Too many arguments in $address_pipe "
2261 "\"%s\" in %s", addr->local_part + 1, etext);
2264 addr->transport_return = FAIL;
2265 addr->message = msg;
2271 /* address_pipe_argcount - 1
2272 * because we are replacing $address_pipe in the argument list
2273 * with the first thing it expands to */
2274 if (argcount + address_pipe_argcount - 1 > max_args)
2276 addr->transport_return = FAIL;
2277 addr->message = string_sprintf("Too many arguments to command "
2278 "\"%s\" after expanding $address_pipe in %s", cmd, etext);
2282 /* If we are not just able to replace the slot that contained
2283 * $address_pipe (address_pipe_argcount == 1)
2284 * We have to move the existing argv by address_pipe_argcount - 1
2285 * Visually if address_pipe_argcount == 2:
2286 * [argv 0][argv 1][argv 2($address_pipe)][argv 3][0]
2287 * [argv 0][argv 1][ap_arg0][ap_arg1][old argv 3][0]
2289 if (address_pipe_argcount > 1)
2291 /* current position + additional args */
2292 argv + i + address_pipe_argcount,
2293 /* current position + 1 (for the (uschar *)0 at the end) */
2295 /* -1 for the (uschar *)0 at the end)*/
2296 (argcount - i)*sizeof(uschar *)
2299 /* Now we fill in the slots we just moved argv out of
2300 * [argv 0][argv 1][argv 2=pipeargv[0]][argv 3=pipeargv[1]][old argv 3][0]
2302 for (address_pipe_i = 0;
2303 address_pipe_argv[address_pipe_i] != (uschar *)0;
2306 argv[i++] = address_pipe_argv[address_pipe_i];
2310 /* Subtract one since we replace $address_pipe */
2315 /* Handle normal expansion string */
2319 const uschar *expanded_arg;
2320 enable_dollar_recipients = allow_dollar_recipients;
2321 expanded_arg = expand_cstring(argv[i]);
2322 enable_dollar_recipients = FALSE;
2324 if (expanded_arg == NULL)
2326 uschar *msg = string_sprintf("Expansion of \"%s\" "
2327 "from command \"%s\" in %s failed: %s",
2328 argv[i], cmd, etext, expand_string_message);
2331 addr->transport_return = expand_failed;
2332 addr->message = msg;
2337 argv[i] = expanded_arg;
2343 debug_printf("direct command after expansion:\n");
2344 for (i = 0; argv[i] != (uschar *)0; i++)
2345 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2354 /* End of transport.c */