Rename dns_use_dnssec to dns_dnssec_ok.
[exim.git] / src / src / transport.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
c4ceed07 5/* Copyright (c) University of Cambridge 1995 - 2012 */
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6/* See the file NOTICE for conditions of use and distribution. */
7
8/* General functions concerned with transportation, and generic options for all
9transports. */
10
11
12#include "exim.h"
13
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14#ifdef HAVE_LINUX_SENDFILE
15#include <sys/sendfile.h>
16#endif
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17
18/* Structure for keeping list of addresses that have been added to
19Envelope-To:, in order to avoid duplication. */
20
21struct aci {
22 struct aci *next;
23 address_item *ptr;
24 };
25
26
27/* Static data for write_chunk() */
28
29static uschar *chunk_ptr; /* chunk pointer */
30static uschar *nl_check; /* string to look for at line start */
31static int nl_check_length; /* length of same */
32static uschar *nl_escape; /* string to insert */
33static int nl_escape_length; /* length of same */
34static int nl_partial_match; /* length matched at chunk end */
35
36
37/* Generic options for transports, all of which live inside transport_instance
38data blocks and which therefore have the opt_public flag set. Note that there
39are other options living inside this structure which can be set only from
40certain transports. */
41
42optionlist 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)) },
69 { "group", opt_expand_gid|opt_public,
70 (void *)offsetof(transport_instance, gid) },
846726c5 71 { "headers_add", opt_stringptr|opt_public|opt_rep_str,
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72 (void *)offsetof(transport_instance, add_headers) },
73 { "headers_only", opt_bool|opt_public,
74 (void *)offsetof(transport_instance, headers_only) },
846726c5 75 { "headers_remove", opt_stringptr|opt_public|opt_rep_str,
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76 (void *)offsetof(transport_instance, remove_headers) },
77 { "headers_rewrite", opt_rewrite|opt_public,
78 (void *)offsetof(transport_instance, headers_rewrite) },
79 { "home_directory", opt_stringptr|opt_public,
80 (void *)offsetof(transport_instance, home_dir) },
81 { "initgroups", opt_bool|opt_public,
82 (void *)offsetof(transport_instance, initgroups) },
83 { "message_size_limit", opt_stringptr|opt_public,
84 (void *)offsetof(transport_instance, message_size_limit) },
85 { "rcpt_include_affixes", opt_bool|opt_public,
86 (void *)offsetof(transport_instance, rcpt_include_affixes) },
87 { "retry_use_local_part", opt_bool|opt_public,
88 (void *)offsetof(transport_instance, retry_use_local_part) },
89 { "return_path", opt_stringptr|opt_public,
90 (void *)(offsetof(transport_instance, return_path)) },
91 { "return_path_add", opt_bool|opt_public,
92 (void *)(offsetof(transport_instance, return_path_add)) },
93 { "shadow_condition", opt_stringptr|opt_public,
94 (void *)offsetof(transport_instance, shadow_condition) },
95 { "shadow_transport", opt_stringptr|opt_public,
96 (void *)offsetof(transport_instance, shadow) },
97 { "transport_filter", opt_stringptr|opt_public,
98 (void *)offsetof(transport_instance, filter_command) },
99 { "transport_filter_timeout", opt_time|opt_public,
100 (void *)offsetof(transport_instance, filter_timeout) },
101 { "user", opt_expand_uid|opt_public,
102 (void *)offsetof(transport_instance, uid) }
103};
104
105int optionlist_transports_size =
106 sizeof(optionlist_transports)/sizeof(optionlist);
107
108
109/*************************************************
110* Initialize transport list *
111*************************************************/
112
113/* Read the transports section of the configuration file, and set up a chain of
114transport instances according to its contents. Each transport has generic
115options and may also have its own private options. This function is only ever
116called when transports == NULL. We use generic code in readconf to do most of
117the work. */
118
119void
120transport_init(void)
121{
122transport_instance *t;
123
124readconf_driver_init(US"transport",
125 (driver_instance **)(&transports), /* chain anchor */
126 (driver_info *)transports_available, /* available drivers */
127 sizeof(transport_info), /* size of info block */
128 &transport_defaults, /* default values for generic options */
129 sizeof(transport_instance), /* size of instance block */
130 optionlist_transports, /* generic options */
131 optionlist_transports_size);
132
133/* Now scan the configured transports and check inconsistencies. A shadow
134transport is permitted only for local transports. */
135
136for (t = transports; t != NULL; t = t->next)
137 {
138 if (!t->info->local)
139 {
140 if (t->shadow != NULL)
141 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
142 "shadow transport not allowed on non-local transport %s", t->name);
143 }
144
145 if (t->body_only && t->headers_only)
146 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
147 "%s transport: body_only and headers_only are mutually exclusive",
148 t->name);
149 }
150}
151
152
153
154/*************************************************
155* Write block of data *
156*************************************************/
157
158/* Subroutine called by write_chunk() and at the end of the message actually
159to write a data block. Also called directly by some transports to write
160additional data to the file descriptor (e.g. prefix, suffix).
161
162If a transport wants data transfers to be timed, it sets a non-zero value in
163transport_write_timeout. A non-zero transport_write_timeout causes a timer to
164be set for each block of data written from here. If time runs out, then write()
165fails and provokes an error return. The caller can then inspect sigalrm_seen to
166check for a timeout.
167
168On some systems, if a quota is exceeded during the write, the yield is the
169number of bytes written rather than an immediate error code. This also happens
170on some systems in other cases, for example a pipe that goes away because the
171other end's process terminates (Linux). On other systems, (e.g. Solaris 2) you
172get the error codes the first time.
173
174The write() function is also interruptible; the Solaris 2.6 man page says:
175
176 If write() is interrupted by a signal before it writes any
177 data, it will return -1 with errno set to EINTR.
178
179 If write() is interrupted by a signal after it successfully
180 writes some data, it will return the number of bytes written.
181
182To handle these cases, we want to restart the write() to output the remainder
183of the data after a non-negative return from write(), except after a timeout.
184In the error cases (EDQUOT, EPIPE) no bytes get written the second time, and a
185proper error then occurs. In principle, after an interruption, the second
186write() could suffer the same fate, but we do not want to continue for
187evermore, so stick a maximum repetition count on the loop to act as a
188longstop.
189
190Arguments:
191 fd file descriptor to write to
192 block block of bytes to write
193 len number of bytes to write
194
195Returns: TRUE on success, FALSE on failure (with errno preserved);
196 transport_count is incremented by the number of bytes written
197*/
198
199BOOL
200transport_write_block(int fd, uschar *block, int len)
201{
202int i, rc, save_errno;
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203int local_timeout = transport_write_timeout;
204
205/* This loop is for handling incomplete writes and other retries. In most
206normal cases, it is only ever executed once. */
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207
208for (i = 0; i < 100; i++)
209 {
210 DEBUG(D_transport)
211 debug_printf("writing data block fd=%d size=%d timeout=%d\n",
958541e9 212 fd, len, local_timeout);
059ec3d9 213
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214 /* This code makes use of alarm() in order to implement the timeout. This
215 isn't a very tidy way of doing things. Using non-blocking I/O with select()
216 provides a neater approach. However, I don't know how to do this when TLS is
217 in use. */
059ec3d9 218
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219 if (transport_write_timeout <= 0) /* No timeout wanted */
220 {
221 #ifdef SUPPORT_TLS
817d9f57 222 if (tls_out.active == fd) rc = tls_write(FALSE, block, len); else
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223 #endif
224 rc = write(fd, block, len);
225 save_errno = errno;
226 }
059ec3d9 227
958541e9 228 /* Timeout wanted. */
059ec3d9 229
958541e9 230 else
059ec3d9 231 {
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232 alarm(local_timeout);
233 #ifdef SUPPORT_TLS
817d9f57 234 if (tls_out.active == fd) rc = tls_write(FALSE, block, len); else
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235 #endif
236 rc = write(fd, block, len);
237 save_errno = errno;
238 local_timeout = alarm(0);
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239 if (sigalrm_seen)
240 {
241 errno = ETIMEDOUT;
242 return FALSE;
243 }
244 }
245
246 /* Hopefully, the most common case is success, so test that first. */
247
248 if (rc == len) { transport_count += len; return TRUE; }
249
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250 /* A non-negative return code is an incomplete write. Try again for the rest
251 of the block. If we have exactly hit the timeout, give up. */
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252
253 if (rc >= 0)
254 {
255 len -= rc;
256 block += rc;
257 transport_count += rc;
258 DEBUG(D_transport) debug_printf("write incomplete (%d)\n", rc);
958541e9 259 goto CHECK_TIMEOUT; /* A few lines below */
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260 }
261
262 /* A negative return code with an EINTR error is another form of
263 incomplete write, zero bytes having been written */
264
265 if (save_errno == EINTR)
266 {
267 DEBUG(D_transport)
268 debug_printf("write interrupted before anything written\n");
958541e9 269 goto CHECK_TIMEOUT; /* A few lines below */
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270 }
271
272 /* A response of EAGAIN from write() is likely only in the case of writing
273 to a FIFO that is not swallowing the data as fast as Exim is writing it. */
274
275 if (save_errno == EAGAIN)
276 {
277 DEBUG(D_transport)
278 debug_printf("write temporarily locked out, waiting 1 sec\n");
279 sleep(1);
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280
281 /* Before continuing to try another write, check that we haven't run out of
282 time. */
283
284 CHECK_TIMEOUT:
285 if (transport_write_timeout > 0 && local_timeout <= 0)
286 {
287 errno = ETIMEDOUT;
288 return FALSE;
289 }
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290 continue;
291 }
292
293 /* Otherwise there's been an error */
294
295 DEBUG(D_transport) debug_printf("writing error %d: %s\n", save_errno,
296 strerror(save_errno));
297 errno = save_errno;
298 return FALSE;
299 }
300
301/* We've tried and tried and tried but still failed */
302
303errno = ERRNO_WRITEINCOMPLETE;
304return FALSE;
305}
306
307
308
309
310/*************************************************
311* Write formatted string *
312*************************************************/
313
314/* This is called by various transports. It is a convenience function.
315
316Arguments:
317 fd file descriptor
318 format string format
319 ... arguments for format
320
321Returns: the yield of transport_write_block()
322*/
323
324BOOL
1ba28e2b 325transport_write_string(int fd, const char *format, ...)
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326{
327va_list ap;
328va_start(ap, format);
329if (!string_vformat(big_buffer, big_buffer_size, format, ap))
330 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong formatted string in transport");
331va_end(ap);
332return transport_write_block(fd, big_buffer, Ustrlen(big_buffer));
333}
334
335
336
337
338/*************************************************
339* Write character chunk *
340*************************************************/
341
342/* Subroutine used by transport_write_message() to scan character chunks for
343newlines and act appropriately. The object is to minimise the number of writes.
344The output byte stream is buffered up in deliver_out_buffer, which is written
345only when it gets full, thus minimizing write operations and TCP packets.
346
347Static data is used to handle the case when the last character of the previous
348chunk was NL, or matched part of the data that has to be escaped.
349
350Arguments:
351 fd file descript to write to
352 chunk pointer to data to write
353 len length of data to write
354 usr_crlf TRUE if CR LF is wanted at the end of each line
355
356In addition, the static nl_xxx variables must be set as required.
357
358Returns: TRUE on success, FALSE on failure (with errno preserved)
359*/
360
361static BOOL
362write_chunk(int fd, uschar *chunk, int len, BOOL use_crlf)
363{
364uschar *start = chunk;
365uschar *end = chunk + len;
366register uschar *ptr;
367int mlen = DELIVER_OUT_BUFFER_SIZE - nl_escape_length - 2;
368
369/* The assumption is made that the check string will never stretch over move
370than one chunk since the only time there are partial matches is when copying
371the body in large buffers. There is always enough room in the buffer for an
372escape string, since the loop below ensures this for each character it
373processes, and it won't have stuck in the escape string if it left a partial
374match. */
375
376if (nl_partial_match >= 0)
377 {
378 if (nl_check_length > 0 && len >= nl_check_length &&
379 Ustrncmp(start, nl_check + nl_partial_match,
380 nl_check_length - nl_partial_match) == 0)
381 {
382 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
383 chunk_ptr += nl_escape_length;
384 start += nl_check_length - nl_partial_match;
385 }
386
387 /* The partial match was a false one. Insert the characters carried over
388 from the previous chunk. */
389
390 else if (nl_partial_match > 0)
391 {
392 Ustrncpy(chunk_ptr, nl_check, nl_partial_match);
393 chunk_ptr += nl_partial_match;
394 }
395
396 nl_partial_match = -1;
397 }
398
399/* Now process the characters in the chunk. Whenever we hit a newline we check
400for possible escaping. The code for the non-NL route should be as fast as
401possible. */
402
403for (ptr = start; ptr < end; ptr++)
404 {
405 register int ch;
406
407 /* Flush the buffer if it has reached the threshold - we want to leave enough
408 room for the next uschar, plus a possible extra CR for an LF, plus the escape
409 string. */
410
411 if (chunk_ptr - deliver_out_buffer > mlen)
412 {
413 if (!transport_write_block(fd, deliver_out_buffer,
414 chunk_ptr - deliver_out_buffer))
415 return FALSE;
416 chunk_ptr = deliver_out_buffer;
417 }
418
419 if ((ch = *ptr) == '\n')
420 {
421 int left = end - ptr - 1; /* count of chars left after NL */
422
423 /* Insert CR before NL if required */
424
425 if (use_crlf) *chunk_ptr++ = '\r';
426 *chunk_ptr++ = '\n';
332f5cf3 427 transport_newlines++;
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428
429 /* The check_string test (formerly "from hack") replaces the specific
430 string at the start of a line with an escape string (e.g. "From " becomes
431 ">From " or "." becomes "..". It is a case-sensitive test. The length
432 check above ensures there is always enough room to insert this string. */
433
434 if (nl_check_length > 0)
435 {
436 if (left >= nl_check_length &&
437 Ustrncmp(ptr+1, nl_check, nl_check_length) == 0)
438 {
439 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
440 chunk_ptr += nl_escape_length;
441 ptr += nl_check_length;
442 }
443
444 /* Handle the case when there isn't enough left to match the whole
445 check string, but there may be a partial match. We remember how many
446 characters matched, and finish processing this chunk. */
447
448 else if (left <= 0) nl_partial_match = 0;
449
450 else if (Ustrncmp(ptr+1, nl_check, left) == 0)
451 {
452 nl_partial_match = left;
453 ptr = end;
454 }
455 }
456 }
457
458 /* Not a NL character */
459
460 else *chunk_ptr++ = ch;
461 }
462
463return TRUE;
464}
465
466
467
468
469/*************************************************
470* Generate address for RCPT TO *
471*************************************************/
472
473/* This function puts together an address for RCPT to, using the caseful
474version of the local part and the caseful version of the domain. If there is no
475prefix or suffix, or if affixes are to be retained, we can just use the
476original address. Otherwise, if there is a prefix but no suffix we can use a
477pointer into the original address. If there is a suffix, however, we have to
478build a new string.
479
480Arguments:
481 addr the address item
482 include_affixes TRUE if affixes are to be included
483
484Returns: a string
485*/
486
487uschar *
488transport_rcpt_address(address_item *addr, BOOL include_affixes)
489{
490uschar *at;
491int plen, slen;
492
493if (include_affixes)
494 {
495 setflag(addr, af_include_affixes); /* Affects logged => line */
496 return addr->address;
497 }
498
499if (addr->suffix == NULL)
500 {
501 if (addr->prefix == NULL) return addr->address;
502 return addr->address + Ustrlen(addr->prefix);
503 }
504
505at = Ustrrchr(addr->address, '@');
506plen = (addr->prefix == NULL)? 0 : Ustrlen(addr->prefix);
507slen = Ustrlen(addr->suffix);
508
509return string_sprintf("%.*s@%s", (at - addr->address - plen - slen),
510 addr->address + plen, at + 1);
511}
512
513
514/*************************************************
515* Output Envelope-To: address & scan duplicates *
516*************************************************/
517
518/* This function is called from internal_transport_write_message() below, when
519generating an Envelope-To: header line. It checks for duplicates of the given
520address and its ancestors. When one is found, this function calls itself
521recursively, to output the envelope address of the duplicate.
522
523We want to avoid duplication in the list, which can arise for example when
524A->B,C and then both B and C alias to D. This can also happen when there are
525unseen drivers in use. So a list of addresses that have been output is kept in
526the plist variable.
527
528It is also possible to have loops in the address ancestry/duplication graph,
529for example if there are two top level addresses A and B and we have A->B,C and
530B->A. To break the loop, we use a list of processed addresses in the dlist
531variable.
532
533After handling duplication, this function outputs the progenitor of the given
534address.
535
536Arguments:
537 p the address we are interested in
538 pplist address of anchor of the list of addresses not to output
539 pdlist address of anchor of the list of processed addresses
540 first TRUE if this is the first address; set it FALSE afterwards
541 fd the file descriptor to write to
542 use_crlf to be passed on to write_chunk()
543
544Returns: FALSE if writing failed
545*/
546
547static BOOL
548write_env_to(address_item *p, struct aci **pplist, struct aci **pdlist,
549 BOOL *first, int fd, BOOL use_crlf)
550{
551address_item *pp;
552struct aci *ppp;
553
554/* Do nothing if we have already handled this address. If not, remember it
555so that we don't handle it again. */
556
557for (ppp = *pdlist; ppp != NULL; ppp = ppp->next)
558 { if (p == ppp->ptr) return TRUE; }
559
560ppp = store_get(sizeof(struct aci));
561ppp->next = *pdlist;
562*pdlist = ppp;
563ppp->ptr = p;
564
565/* Now scan up the ancestry, checking for duplicates at each generation. */
566
567for (pp = p;; pp = pp->parent)
568 {
569 address_item *dup;
570 for (dup = addr_duplicate; dup != NULL; dup = dup->next)
571 {
572 if (dup->dupof != pp) continue; /* Not a dup of our address */
573 if (!write_env_to(dup, pplist, pdlist, first, fd, use_crlf)) return FALSE;
574 }
575 if (pp->parent == NULL) break;
576 }
577
578/* Check to see if we have already output the progenitor. */
579
580for (ppp = *pplist; ppp != NULL; ppp = ppp->next)
581 { if (pp == ppp->ptr) break; }
582if (ppp != NULL) return TRUE;
583
584/* Remember what we have output, and output it. */
585
586ppp = store_get(sizeof(struct aci));
587ppp->next = *pplist;
588*pplist = ppp;
589ppp->ptr = pp;
590
591if (!(*first) && !write_chunk(fd, US",\n ", 3, use_crlf)) return FALSE;
592*first = FALSE;
593return write_chunk(fd, pp->address, Ustrlen(pp->address), use_crlf);
594}
595
596
597
598
599/*************************************************
600* Write the message *
601*************************************************/
602
603/* This function writes the message to the given file descriptor. The headers
604are in the in-store data structure, and the rest of the message is in the open
605file descriptor deliver_datafile. Make sure we start it at the beginning.
606
607. If add_return_path is TRUE, a "return-path:" header is added to the message,
608 containing the envelope sender's address.
609
610. If add_envelope_to is TRUE, a "envelope-to:" header is added to the message,
611 giving the top-level envelope address that caused this delivery to happen.
612
613. If add_delivery_date is TRUE, a "delivery-date:" header is added to the
614 message. It gives the time and date that delivery took place.
615
616. If check_string is not null, the start of each line is checked for that
617 string. If it is found, it is replaced by escape_string. This used to be
618 the "from hack" for files, and "smtp_dots" for escaping SMTP dots.
619
620. If use_crlf is true, newlines are turned into CRLF (SMTP output).
621
622The yield is TRUE if all went well, and FALSE if not. Exit *immediately* after
623any writing or reading error, leaving the code in errno intact. Error exits
624can include timeouts for certain transports, which are requested by setting
625transport_write_timeout non-zero.
626
627Arguments:
628 addr (chain of) addresses (for extra headers), or NULL;
629 only the first address is used
630 fd file descriptor to write the message to
631 options bit-wise options:
632 add_return_path if TRUE, add a "return-path" header
633 add_envelope_to if TRUE, add a "envelope-to" header
634 add_delivery_date if TRUE, add a "delivery-date" header
635 use_crlf if TRUE, turn NL into CR LF
636 end_dot if TRUE, send a terminating "." line at the end
637 no_headers if TRUE, omit the headers
638 no_body if TRUE, omit the body
639 size_limit if > 0, this is a limit to the size of message written;
640 it is used when returning messages to their senders,
641 and is approximate rather than exact, owing to chunk
642 buffering
643 add_headers a string containing one or more headers to add; it is
644 expanded, and must be in correct RFC 822 format as
645 it is transmitted verbatim; NULL => no additions,
646 and so does empty string or forced expansion fail
647 remove_headers a colon-separated list of headers to remove, or NULL
648 check_string a string to check for at the start of lines, or NULL
649 escape_string a string to insert in front of any check string
650 rewrite_rules chain of header rewriting rules
651 rewrite_existflags flags for the rewriting rules
652
653Returns: TRUE on success; FALSE (with errno) on failure.
654 In addition, the global variable transport_count
655 is incremented by the number of bytes written.
656*/
657
658static BOOL
659internal_transport_write_message(address_item *addr, int fd, int options,
660 int size_limit, uschar *add_headers, uschar *remove_headers, uschar *check_string,
661 uschar *escape_string, rewrite_rule *rewrite_rules, int rewrite_existflags)
662{
663int written = 0;
664int len;
665header_line *h;
666BOOL use_crlf = (options & topt_use_crlf) != 0;
667
668/* Initialize pointer in output buffer. */
669
670chunk_ptr = deliver_out_buffer;
671
672/* Set up the data for start-of-line data checking and escaping */
673
674nl_partial_match = -1;
675if (check_string != NULL && escape_string != NULL)
676 {
677 nl_check = check_string;
678 nl_check_length = Ustrlen(nl_check);
679 nl_escape = escape_string;
680 nl_escape_length = Ustrlen(nl_escape);
681 }
682else nl_check_length = nl_escape_length = 0;
683
684/* Whether the escaping mechanism is applied to headers or not is controlled by
685an option (set for SMTP, not otherwise). Negate the length if not wanted till
686after the headers. */
687
688if ((options & topt_escape_headers) == 0) nl_check_length = -nl_check_length;
689
690/* Write the headers if required, including any that have to be added. If there
691are header rewriting rules, apply them. */
692
693if ((options & topt_no_headers) == 0)
694 {
695 /* Add return-path: if requested. */
696
697 if ((options & topt_add_return_path) != 0)
698 {
699 uschar buffer[ADDRESS_MAXLENGTH + 20];
700 sprintf(CS buffer, "Return-path: <%.*s>\n", ADDRESS_MAXLENGTH,
701 return_path);
702 if (!write_chunk(fd, buffer, Ustrlen(buffer), use_crlf)) return FALSE;
703 }
704
705 /* Add envelope-to: if requested */
706
707 if ((options & topt_add_envelope_to) != 0)
708 {
709 BOOL first = TRUE;
710 address_item *p;
711 struct aci *plist = NULL;
712 struct aci *dlist = NULL;
713 void *reset_point = store_get(0);
714
715 if (!write_chunk(fd, US"Envelope-to: ", 13, use_crlf)) return FALSE;
716
717 /* Pick up from all the addresses. The plist and dlist variables are
718 anchors for lists of addresses already handled; they have to be defined at
719 this level becuase write_env_to() calls itself recursively. */
720
721 for (p = addr; p != NULL; p = p->next)
722 {
723 if (!write_env_to(p, &plist, &dlist, &first, fd, use_crlf)) return FALSE;
724 }
725
726 /* Add a final newline and reset the store used for tracking duplicates */
727
728 if (!write_chunk(fd, US"\n", 1, use_crlf)) return FALSE;
729 store_reset(reset_point);
730 }
731
732 /* Add delivery-date: if requested. */
733
734 if ((options & topt_add_delivery_date) != 0)
735 {
736 uschar buffer[100];
737 sprintf(CS buffer, "Delivery-date: %s\n", tod_stamp(tod_full));
738 if (!write_chunk(fd, buffer, Ustrlen(buffer), use_crlf)) return FALSE;
739 }
740
741 /* Then the message's headers. Don't write any that are flagged as "old";
742 that means they were rewritten, or are a record of envelope rewriting, or
743 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
744 match any entries therein. Then check addr->p.remove_headers too, provided that
745 addr is not NULL. */
746
747 if (remove_headers != NULL)
748 {
749 uschar *s = expand_string(remove_headers);
750 if (s == NULL && !expand_string_forcedfail)
751 {
752 errno = ERRNO_CHHEADER_FAIL;
753 return FALSE;
754 }
755 remove_headers = s;
756 }
757
758 for (h = header_list; h != NULL; h = h->next)
759 {
760 int i;
761 uschar *list = NULL;
762 BOOL include_header;
763
764 if (h->type == htype_old) continue;
765
766 include_header = TRUE;
767 list = remove_headers;
768
769 for (i = 0; i < 2; i++) /* For remove_headers && addr->p.remove_headers */
770 {
771 if (list != NULL)
772 {
773 int sep = ':'; /* This is specified as a colon-separated list */
774 uschar *s, *ss;
775 uschar buffer[128];
776 while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer)))
777 != NULL)
778 {
779 int len = Ustrlen(s);
780 if (strncmpic(h->text, s, len) != 0) continue;
781 ss = h->text + len;
782 while (*ss == ' ' || *ss == '\t') ss++;
783 if (*ss == ':') break;
784 }
785 if (s != NULL) { include_header = FALSE; break; }
786 }
787 if (addr != NULL) list = addr->p.remove_headers;
788 }
789
790 /* If this header is to be output, try to rewrite it if there are rewriting
791 rules. */
792
793 if (include_header)
794 {
795 if (rewrite_rules != NULL)
796 {
797 void *reset_point = store_get(0);
798 header_line *hh =
799 rewrite_header(h, NULL, NULL, rewrite_rules, rewrite_existflags,
800 FALSE);
801 if (hh != NULL)
802 {
803 if (!write_chunk(fd, hh->text, hh->slen, use_crlf)) return FALSE;
804 store_reset(reset_point);
805 continue; /* With the next header line */
806 }
807 }
808
809 /* Either no rewriting rules, or it didn't get rewritten */
810
811 if (!write_chunk(fd, h->text, h->slen, use_crlf)) return FALSE;
812 }
813
814 /* Header removed */
815
816 else
817 {
818 DEBUG(D_transport) debug_printf("removed header line:\n%s---\n",
819 h->text);
820 }
821 }
822
823 /* Add on any address-specific headers. If there are multiple addresses,
824 they will all have the same headers in order to be batched. The headers
825 are chained in reverse order of adding (so several addresses from the
826 same alias might share some of them) but we want to output them in the
827 opposite order. This is a bit tedious, but there shouldn't be very many
828 of them. We just walk the list twice, reversing the pointers each time,
7999bbd7
PH
829 but on the second time, write out the items.
830
831 Headers added to an address by a router are guaranteed to end with a newline.
832 */
059ec3d9
PH
833
834 if (addr != NULL)
835 {
836 int i;
837 header_line *hprev = addr->p.extra_headers;
838 header_line *hnext;
839 for (i = 0; i < 2; i++)
840 {
841 for (h = hprev, hprev = NULL; h != NULL; h = hnext)
842 {
843 hnext = h->next;
844 h->next = hprev;
845 hprev = h;
846 if (i == 1)
847 {
848 if (!write_chunk(fd, h->text, h->slen, use_crlf)) return FALSE;
849 DEBUG(D_transport)
850 debug_printf("added header line(s):\n%s---\n", h->text);
851 }
852 }
853 }
854 }
855
856 /* If a string containing additional headers exists, expand it and write
857 out the result. This is done last so that if it (deliberately or accidentally)
858 isn't in header format, it won't mess up any other headers. An empty string
7999bbd7
PH
859 or a forced expansion failure are noops. An added header string from a
860 transport may not end with a newline; add one if it does not. */
059ec3d9
PH
861
862 if (add_headers != NULL)
863 {
864 uschar *s = expand_string(add_headers);
865 if (s == NULL)
866 {
867 if (!expand_string_forcedfail)
868 {
869 errno = ERRNO_CHHEADER_FAIL;
870 return FALSE;
871 }
872 }
873 else
874 {
875 int len = Ustrlen(s);
876 if (len > 0)
877 {
878 if (!write_chunk(fd, s, len, use_crlf)) return FALSE;
879 if (s[len-1] != '\n' && !write_chunk(fd, US"\n", 1, use_crlf))
880 return FALSE;
881 DEBUG(D_transport)
7999bbd7
PH
882 {
883 debug_printf("added header line(s):\n%s", s);
884 if (s[len-1] != '\n') debug_printf("\n");
885 debug_printf("---\n");
886 }
059ec3d9
PH
887 }
888 }
889 }
890
891 /* Separate headers from body with a blank line */
892
893 if (!write_chunk(fd, US"\n", 1, use_crlf)) return FALSE;
894 }
895
896/* If the body is required, ensure that the data for check strings (formerly
897the "from hack") is enabled by negating the length if necessary. (It will be
898negative in cases where it isn't to apply to the headers). Then ensure the body
899is positioned at the start of its file (following the message id), then write
900it, applying the size limit if required. */
901
902if ((options & topt_no_body) == 0)
903 {
904 nl_check_length = abs(nl_check_length);
905 nl_partial_match = 0;
906 lseek(deliver_datafile, SPOOL_DATA_START_OFFSET, SEEK_SET);
907 while ((len = read(deliver_datafile, deliver_in_buffer,
908 DELIVER_IN_BUFFER_SIZE)) > 0)
909 {
910 if (!write_chunk(fd, deliver_in_buffer, len, use_crlf)) return FALSE;
911 if (size_limit > 0)
912 {
913 written += len;
914 if (written > size_limit)
915 {
916 len = 0; /* Pretend EOF */
917 break;
918 }
919 }
920 }
921
059ec3d9
PH
922 /* A read error on the body will have left len == -1 and errno set. */
923
924 if (len != 0) return FALSE;
c0940526 925 }
059ec3d9 926
c0940526 927/* Finished with the check string */
059ec3d9 928
c0940526
PP
929nl_check_length = nl_escape_length = 0;
930
931/* If requested, add a terminating "." line (SMTP output). */
932
933if ((options & topt_end_dot) != 0 && !write_chunk(fd, US".\n", 2, use_crlf))
934 return FALSE;
059ec3d9
PH
935
936/* Write out any remaining data in the buffer before returning. */
937
938return (len = chunk_ptr - deliver_out_buffer) <= 0 ||
939 transport_write_block(fd, deliver_out_buffer, len);
940}
941
942
80a47a2c 943#ifndef DISABLE_DKIM
fb2274d4 944
4cd12fe9
TK
945/***************************************************************************************************
946* External interface to write the message, while signing it with DKIM and/or Domainkeys *
947***************************************************************************************************/
fb2274d4
TK
948
949/* This function is a wrapper around transport_write_message(). It is only called
4cd12fe9 950 from the smtp transport if DKIM or Domainkeys support is compiled in.
fb2274d4
TK
951 The function sets up a replacement fd into a -K file, then calls the normal
952 function. This way, the exact bits that exim would have put "on the wire" will
953 end up in the file (except for TLS encapsulation, which is the very
954 very last thing). When we are done signing the file, send the
955 signed message down the original fd (or TLS fd).
956
957Arguments: as for internal_transport_write_message() above, with additional
84330b7b 958 arguments:
4cd12fe9
TK
959 uschar *dkim_private_key DKIM: The private key to use (filename or plain data)
960 uschar *dkim_domain DKIM: The domain to use
961 uschar *dkim_selector DKIM: The selector to use.
962 uschar *dkim_canon DKIM: The canonalization scheme to use, "simple" or "relaxed"
963 uschar *dkim_strict DKIM: What to do if signing fails: 1/true => throw error
964 0/false => send anyway
965 uschar *dkim_sign_headers DKIM: List of headers that should be included in signature
966 generation
f7572e5a
TK
967
968Returns: TRUE on success; FALSE (with errno) for any failure
969*/
970
971BOOL
972dkim_transport_write_message(address_item *addr, int fd, int options,
973 int size_limit, uschar *add_headers, uschar *remove_headers,
974 uschar *check_string, uschar *escape_string, rewrite_rule *rewrite_rules,
975 int rewrite_existflags, uschar *dkim_private_key, uschar *dkim_domain,
80a47a2c 976 uschar *dkim_selector, uschar *dkim_canon, uschar *dkim_strict, uschar *dkim_sign_headers
4cd12fe9 977 )
f7572e5a
TK
978{
979 int dkim_fd;
980 int save_errno = 0;
981 BOOL rc;
982 uschar dkim_spool_name[256];
983 char sbuf[2048];
984 int sread = 0;
985 int wwritten = 0;
986 uschar *dkim_signature = NULL;
987 off_t size = 0;
988
80a47a2c
TK
989 if (!( ((dkim_private_key != NULL) && (dkim_domain != NULL) && (dkim_selector != NULL)) )) {
990 /* If we can't sign, just call the original function. */
4cd12fe9
TK
991 return transport_write_message(addr, fd, options,
992 size_limit, add_headers, remove_headers,
993 check_string, escape_string, rewrite_rules,
994 rewrite_existflags);
995 }
996
f7572e5a
TK
997 (void)string_format(dkim_spool_name, 256, "%s/input/%s/%s-%d-K",
998 spool_directory, message_subdir, message_id, (int)getpid());
999 dkim_fd = Uopen(dkim_spool_name, O_RDWR|O_CREAT|O_TRUNC, SPOOL_MODE);
1000 if (dkim_fd < 0)
1001 {
1002 /* Can't create spool file. Ugh. */
1003 rc = FALSE;
1004 save_errno = errno;
1005 goto CLEANUP;
1006 }
1007
1008 /* Call original function */
1009 rc = transport_write_message(addr, dkim_fd, options,
1010 size_limit, add_headers, remove_headers,
1011 check_string, escape_string, rewrite_rules,
1012 rewrite_existflags);
1013
1014 /* Save error state. We must clean up before returning. */
1015 if (!rc)
1016 {
1017 save_errno = errno;
1018 goto CLEANUP;
1019 }
1020
4cd12fe9
TK
1021 if ( (dkim_private_key != NULL) && (dkim_domain != NULL) && (dkim_selector != NULL) ) {
1022 /* Rewind file and feed it to the goats^W DKIM lib */
1023 lseek(dkim_fd, 0, SEEK_SET);
1024 dkim_signature = dkim_exim_sign(dkim_fd,
1025 dkim_private_key,
1026 dkim_domain,
1027 dkim_selector,
1028 dkim_canon,
1029 dkim_sign_headers);
1030 if (dkim_signature == NULL) {
1031 if (dkim_strict != NULL) {
1032 uschar *dkim_strict_result = expand_string(dkim_strict);
1033 if (dkim_strict_result != NULL) {
1034 if ( (strcmpic(dkim_strict,US"1") == 0) ||
1035 (strcmpic(dkim_strict,US"true") == 0) ) {
dcdf4e3e
TK
1036 /* Set errno to something halfway meaningful */
1037 save_errno = EACCES;
1038 log_write(0, LOG_MAIN, "DKIM: message could not be signed, and dkim_strict is set. Deferring message delivery.");
4cd12fe9
TK
1039 rc = FALSE;
1040 goto CLEANUP;
1041 }
f7572e5a 1042 }
f7572e5a
TK
1043 }
1044 }
4cd12fe9
TK
1045 else {
1046 int siglen = Ustrlen(dkim_signature);
1047 while(siglen > 0) {
1048 #ifdef SUPPORT_TLS
817d9f57 1049 if (tls_out.active == fd) wwritten = tls_write(FALSE, dkim_signature, siglen); else
4cd12fe9
TK
1050 #endif
1051 wwritten = write(fd,dkim_signature,siglen);
1052 if (wwritten == -1) {
1053 /* error, bail out */
1054 save_errno = errno;
1055 rc = FALSE;
1056 goto CLEANUP;
f7572e5a 1057 }
4cd12fe9
TK
1058 siglen -= wwritten;
1059 dkim_signature += wwritten;
f7572e5a
TK
1060 }
1061 }
4cd12fe9 1062 }
f7572e5a
TK
1063
1064 /* Fetch file positition (the size) */
1065 size = lseek(dkim_fd,0,SEEK_CUR);
1066
1067 /* Rewind file */
1068 lseek(dkim_fd, 0, SEEK_SET);
1069
1070#ifdef HAVE_LINUX_SENDFILE
1071 /* We can use sendfile() to shove the file contents
1072 to the socket. However only if we don't use TLS,
1073 in which case theres another layer of indirection
1074 before the data finally hits the socket. */
817d9f57 1075 if (tls_out.active != fd)
f7572e5a
TK
1076 {
1077 ssize_t copied = 0;
1078 off_t offset = 0;
1079 while((copied >= 0) && (offset<size))
1080 {
1081 copied = sendfile(fd, dkim_fd, &offset, (size - offset));
1082 }
1083 if (copied < 0)
1084 {
1085 save_errno = errno;
1086 rc = FALSE;
1087 }
1088 goto CLEANUP;
1089 }
1090#endif
1091
1092 /* Send file down the original fd */
1093 while((sread = read(dkim_fd,sbuf,2048)) > 0)
1094 {
1095 char *p = sbuf;
1096 /* write the chunk */
1097 DKIM_WRITE:
1098 #ifdef SUPPORT_TLS
817d9f57 1099 if (tls_out.active == fd) wwritten = tls_write(FALSE, US p, sread); else
f7572e5a
TK
1100 #endif
1101 wwritten = write(fd,p,sread);
1102 if (wwritten == -1)
1103 {
1104 /* error, bail out */
1105 save_errno = errno;
1106 rc = FALSE;
1107 goto CLEANUP;
1108 }
1109 if (wwritten < sread)
1110 {
1111 /* short write, try again */
1112 p += wwritten;
1113 sread -= wwritten;
1114 goto DKIM_WRITE;
1115 }
1116 }
1117
1118 if (sread == -1)
1119 {
1120 save_errno = errno;
1121 rc = FALSE;
1122 goto CLEANUP;
1123 }
1124
1125 CLEANUP:
1126 /* unlink -K file */
1127 (void)close(dkim_fd);
fc2ba559 1128 Uunlink(dkim_spool_name);
f7572e5a
TK
1129 errno = save_errno;
1130 return rc;
1131}
80a47a2c 1132
f7572e5a
TK
1133#endif
1134
1135
1136
059ec3d9
PH
1137/*************************************************
1138* External interface to write the message *
1139*************************************************/
1140
1141/* If there is no filtering required, call the internal function above to do
1142the real work, passing over all the arguments from this function. Otherwise,
1143set up a filtering process, fork another process to call the internal function
1144to write to the filter, and in this process just suck from the filter and write
1145down the given fd. At the end, tidy up the pipes and the processes.
1146
1147Arguments: as for internal_transport_write_message() above
1148
1149Returns: TRUE on success; FALSE (with errno) for any failure
1150 transport_count is incremented by the number of bytes written
1151*/
1152
1153BOOL
1154transport_write_message(address_item *addr, int fd, int options,
1155 int size_limit, uschar *add_headers, uschar *remove_headers,
1156 uschar *check_string, uschar *escape_string, rewrite_rule *rewrite_rules,
1157 int rewrite_existflags)
1158{
1159BOOL use_crlf;
1160BOOL last_filter_was_NL = TRUE;
1161int rc, len, yield, fd_read, fd_write, save_errno;
1162int pfd[2];
1163pid_t filter_pid, write_pid;
1164
2e2a30b4
PH
1165transport_filter_timed_out = FALSE;
1166
059ec3d9
PH
1167/* If there is no filter command set up, call the internal function that does
1168the actual work, passing it the incoming fd, and return its result. */
1169
1170if (transport_filter_argv == NULL)
1171 return internal_transport_write_message(addr, fd, options, size_limit,
1172 add_headers, remove_headers, check_string, escape_string,
1173 rewrite_rules, rewrite_existflags);
1174
1175/* Otherwise the message must be written to a filter process and read back
1176before being written to the incoming fd. First set up the special processing to
1177be done during the copying. */
1178
1179use_crlf = (options & topt_use_crlf) != 0;
1180nl_partial_match = -1;
1181
1182if (check_string != NULL && escape_string != NULL)
1183 {
1184 nl_check = check_string;
1185 nl_check_length = Ustrlen(nl_check);
1186 nl_escape = escape_string;
1187 nl_escape_length = Ustrlen(nl_escape);
1188 }
1189else nl_check_length = nl_escape_length = 0;
1190
1191/* Start up a subprocess to run the command. Ensure that our main fd will
1192be closed when the subprocess execs, but remove the flag afterwards.
1193(Otherwise, if this is a TCP/IP socket, it can't get passed on to another
1194process to deliver another message.) We get back stdin/stdout file descriptors.
1195If the process creation failed, give an error return. */
1196
1197fd_read = -1;
1198fd_write = -1;
1199save_errno = 0;
1200yield = FALSE;
1201write_pid = (pid_t)(-1);
1202
ff790e47 1203(void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC);
059ec3d9
PH
1204filter_pid = child_open(transport_filter_argv, NULL, 077, &fd_write, &fd_read,
1205 FALSE);
ff790e47 1206(void)fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) & ~FD_CLOEXEC);
059ec3d9
PH
1207if (filter_pid < 0) goto TIDY_UP; /* errno set */
1208
1209DEBUG(D_transport)
1210 debug_printf("process %d running as transport filter: write=%d read=%d\n",
1211 (int)filter_pid, fd_write, fd_read);
1212
1213/* Fork subprocess to write the message to the filter, and return the result
1214via a(nother) pipe. While writing to the filter, we do not do the CRLF,
1215smtp dots, or check string processing. */
1216
1217if (pipe(pfd) != 0) goto TIDY_UP; /* errno set */
1218if ((write_pid = fork()) == 0)
1219 {
1220 BOOL rc;
f1e894f3
PH
1221 (void)close(fd_read);
1222 (void)close(pfd[pipe_read]);
059ec3d9
PH
1223 nl_check_length = nl_escape_length = 0;
1224 rc = internal_transport_write_message(addr, fd_write,
1225 (options & ~(topt_use_crlf | topt_end_dot)),
1226 size_limit, add_headers, remove_headers, NULL, NULL,
1227 rewrite_rules, rewrite_existflags);
1228 save_errno = errno;
1ac6b2e7
JH
1229 if ( write(pfd[pipe_write], (void *)&rc, sizeof(BOOL))
1230 != sizeof(BOOL)
1231 || write(pfd[pipe_write], (void *)&save_errno, sizeof(int))
1232 != sizeof(int)
1233 || write(pfd[pipe_write], (void *)&(addr->more_errno), sizeof(int))
1234 != sizeof(int)
1235 )
1236 rc = FALSE; /* compiler quietening */
059ec3d9
PH
1237 _exit(0);
1238 }
1239save_errno = errno;
1240
1241/* Parent process: close our copy of the writing subprocess' pipes. */
1242
f1e894f3
PH
1243(void)close(pfd[pipe_write]);
1244(void)close(fd_write);
059ec3d9
PH
1245fd_write = -1;
1246
1247/* Writing process creation failed */
1248
1249if (write_pid < 0)
1250 {
1251 errno = save_errno; /* restore */
1252 goto TIDY_UP;
1253 }
1254
1255/* When testing, let the subprocess get going */
1256
1257if (running_in_test_harness) millisleep(250);
1258
1259DEBUG(D_transport)
1260 debug_printf("process %d writing to transport filter\n", (int)write_pid);
1261
1262/* Copy the message from the filter to the output fd. A read error leaves len
1263== -1 and errno set. We need to apply a timeout to the read, to cope with
1264the case when the filter gets stuck, but it can be quite a long one. The
1265default is 5m, but this is now configurable. */
1266
1267DEBUG(D_transport) debug_printf("copying from the filter\n");
1268
1269/* Copy the output of the filter, remembering if the last character was NL. If
1270no data is returned, that counts as "ended with NL" (default setting of the
1271variable is TRUE). */
1272
1273chunk_ptr = deliver_out_buffer;
1274
1275for (;;)
1276 {
1277 sigalrm_seen = FALSE;
1278 alarm(transport_filter_timeout);
1279 len = read(fd_read, deliver_in_buffer, DELIVER_IN_BUFFER_SIZE);
1280 alarm(0);
1281 if (sigalrm_seen)
1282 {
1283 errno = ETIMEDOUT;
2e2a30b4 1284 transport_filter_timed_out = TRUE;
059ec3d9
PH
1285 goto TIDY_UP;
1286 }
1287
1288 /* If the read was successful, write the block down the original fd,
1289 remembering whether it ends in \n or not. */
1290
1291 if (len > 0)
1292 {
1293 if (!write_chunk(fd, deliver_in_buffer, len, use_crlf)) goto TIDY_UP;
1294 last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
1295 }
1296
1297 /* Otherwise, break the loop. If we have hit EOF, set yield = TRUE. */
1298
1299 else
1300 {
1301 if (len == 0) yield = TRUE;
1302 break;
1303 }
1304 }
1305
1306/* Tidying up code. If yield = FALSE there has been an error and errno is set
1307to something. Ensure the pipes are all closed and the processes are removed. If
1308there has been an error, kill the processes before waiting for them, just to be
1309sure. Also apply a paranoia timeout. */
1310
1311TIDY_UP:
1312save_errno = errno;
1313
f1e894f3
PH
1314(void)close(fd_read);
1315if (fd_write > 0) (void)close(fd_write);
059ec3d9
PH
1316
1317if (!yield)
1318 {
1319 if (filter_pid > 0) kill(filter_pid, SIGKILL);
1320 if (write_pid > 0) kill(write_pid, SIGKILL);
1321 }
1322
1323/* Wait for the filter process to complete. */
1324
1325DEBUG(D_transport) debug_printf("waiting for filter process\n");
1326if (filter_pid > 0 && (rc = child_close(filter_pid, 30)) != 0 && yield)
1327 {
1328 yield = FALSE;
1329 save_errno = ERRNO_FILTER_FAIL;
1330 addr->more_errno = rc;
1331 DEBUG(D_transport) debug_printf("filter process returned %d\n", rc);
1332 }
1333
1334/* Wait for the writing process to complete. If it ends successfully,
8e669ac1 1335read the results from its pipe, provided we haven't already had a filter
35af9f61 1336process failure. */
059ec3d9
PH
1337
1338DEBUG(D_transport) debug_printf("waiting for writing process\n");
1339if (write_pid > 0)
1340 {
35af9f61
PH
1341 rc = child_close(write_pid, 30);
1342 if (yield)
059ec3d9 1343 {
8e669ac1 1344 if (rc == 0)
35af9f61
PH
1345 {
1346 BOOL ok;
1ac6b2e7 1347 int dummy = read(pfd[pipe_read], (void *)&ok, sizeof(BOOL));
35af9f61
PH
1348 if (!ok)
1349 {
1ac6b2e7
JH
1350 dummy = read(pfd[pipe_read], (void *)&save_errno, sizeof(int));
1351 dummy = read(pfd[pipe_read], (void *)&(addr->more_errno), sizeof(int));
35af9f61
PH
1352 yield = FALSE;
1353 }
1354 }
1355 else
059ec3d9 1356 {
059ec3d9 1357 yield = FALSE;
35af9f61
PH
1358 save_errno = ERRNO_FILTER_FAIL;
1359 addr->more_errno = rc;
1360 DEBUG(D_transport) debug_printf("writing process returned %d\n", rc);
059ec3d9 1361 }
8e669ac1 1362 }
059ec3d9 1363 }
f1e894f3 1364(void)close(pfd[pipe_read]);
059ec3d9
PH
1365
1366/* If there have been no problems we can now add the terminating "." if this is
1367SMTP output, turning off escaping beforehand. If the last character from the
1368filter was not NL, insert a NL to make the SMTP protocol work. */
1369
1370if (yield)
1371 {
1372 nl_check_length = nl_escape_length = 0;
1373 if ((options & topt_end_dot) != 0 && (last_filter_was_NL?
1374 !write_chunk(fd, US".\n", 2, use_crlf) :
1375 !write_chunk(fd, US"\n.\n", 3, use_crlf)))
1376 {
1377 yield = FALSE;
1378 }
1379
1380 /* Write out any remaining data in the buffer. */
1381
1382 else
1383 {
1384 yield = (len = chunk_ptr - deliver_out_buffer) <= 0 ||
1385 transport_write_block(fd, deliver_out_buffer, len);
1386 }
1387 }
1388else errno = save_errno; /* From some earlier error */
1389
1390DEBUG(D_transport)
1391 {
1392 debug_printf("end of filtering transport writing: yield=%d\n", yield);
1393 if (!yield)
1394 debug_printf("errno=%d more_errno=%d\n", errno, addr->more_errno);
1395 }
1396
1397return yield;
1398}
1399
1400
1401
1402
1403
1404/*************************************************
1405* Update waiting database *
1406*************************************************/
1407
1408/* This is called when an address is deferred by remote transports that are
1409capable of sending more than one message over one connection. A database is
1410maintained for each transport, keeping track of which messages are waiting for
1411which hosts. The transport can then consult this when eventually a successful
1412delivery happens, and if it finds that another message is waiting for the same
1413host, it can fire up a new process to deal with it using the same connection.
1414
1415The database records are keyed by host name. They can get full if there are
1416lots of messages waiting, and so there is a continuation mechanism for them.
1417
1418Each record contains a list of message ids, packed end to end without any
1419zeros. Each one is MESSAGE_ID_LENGTH bytes long. The count field says how many
1420in this record, and the sequence field says if there are any other records for
1421this host. If the sequence field is 0, there are none. If it is 1, then another
1422record with the name <hostname>:0 exists; if it is 2, then two other records
1423with sequence numbers 0 and 1 exist, and so on.
1424
1425Currently, an exhaustive search of all continuation records has to be done to
1426determine whether to add a message id to a given record. This shouldn't be
1427too bad except in extreme cases. I can't figure out a *simple* way of doing
1428better.
1429
1430Old records should eventually get swept up by the exim_tidydb utility.
1431
1432Arguments:
f6c332bd 1433 hostlist list of hosts that this message could be sent to
059ec3d9
PH
1434 tpname name of the transport
1435
1436Returns: nothing
1437*/
1438
1439void
1440transport_update_waiting(host_item *hostlist, uschar *tpname)
1441{
1442uschar buffer[256];
1443uschar *prevname = US"";
1444host_item *host;
1445open_db dbblock;
1446open_db *dbm_file;
1447
7a0743eb
PH
1448DEBUG(D_transport) debug_printf("updating wait-%s database\n", tpname);
1449
059ec3d9
PH
1450/* Open the database for this transport */
1451
1452sprintf(CS buffer, "wait-%.200s", tpname);
1453dbm_file = dbfn_open(buffer, O_RDWR, &dbblock, TRUE);
1454if (dbm_file == NULL) return;
1455
1456/* Scan the list of hosts for which this message is waiting, and ensure
f6c332bd 1457that the message id is in each host record. */
059ec3d9
PH
1458
1459for (host = hostlist; host!= NULL; host = host->next)
1460 {
1461 BOOL already = FALSE;
1462 dbdata_wait *host_record;
1463 uschar *s;
1464 int i, host_length;
1465
059ec3d9
PH
1466 /* Skip if this is the same host as we just processed; otherwise remember
1467 the name for next time. */
1468
1469 if (Ustrcmp(prevname, host->name) == 0) continue;
1470 prevname = host->name;
1471
1472 /* Look up the host record; if there isn't one, make an empty one. */
1473
1474 host_record = dbfn_read(dbm_file, host->name);
1475 if (host_record == NULL)
1476 {
1477 host_record = store_get(sizeof(dbdata_wait) + MESSAGE_ID_LENGTH);
1478 host_record->count = host_record->sequence = 0;
1479 }
1480
1481 /* Compute the current length */
1482
1483 host_length = host_record->count * MESSAGE_ID_LENGTH;
1484
1485 /* Search the record to see if the current message is already in it. */
1486
1487 for (s = host_record->text; s < host_record->text + host_length;
1488 s += MESSAGE_ID_LENGTH)
1489 {
1490 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1491 { already = TRUE; break; }
1492 }
1493
1494 /* If we haven't found this message in the main record, search any
1495 continuation records that exist. */
1496
1497 for (i = host_record->sequence - 1; i >= 0 && !already; i--)
1498 {
1499 dbdata_wait *cont;
1500 sprintf(CS buffer, "%.200s:%d", host->name, i);
1501 cont = dbfn_read(dbm_file, buffer);
1502 if (cont != NULL)
1503 {
1504 int clen = cont->count * MESSAGE_ID_LENGTH;
1505 for (s = cont->text; s < cont->text + clen; s += MESSAGE_ID_LENGTH)
1506 {
1507 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1508 { already = TRUE; break; }
1509 }
1510 }
1511 }
1512
1513 /* If this message is already in a record, no need to update. */
1514
7a0743eb
PH
1515 if (already)
1516 {
1517 DEBUG(D_transport) debug_printf("already listed for %s\n", host->name);
1518 continue;
1519 }
059ec3d9
PH
1520
1521
1522 /* If this record is full, write it out with a new name constructed
1523 from the sequence number, increase the sequence number, and empty
1524 the record. */
1525
1526 if (host_record->count >= WAIT_NAME_MAX)
1527 {
1528 sprintf(CS buffer, "%.200s:%d", host->name, host_record->sequence);
1529 dbfn_write(dbm_file, buffer, host_record, sizeof(dbdata_wait) + host_length);
1530 host_record->sequence++;
1531 host_record->count = 0;
1532 host_length = 0;
1533 }
1534
1535 /* If this record is not full, increase the size of the record to
1536 allow for one new message id. */
1537
1538 else
1539 {
1540 dbdata_wait *newr =
1541 store_get(sizeof(dbdata_wait) + host_length + MESSAGE_ID_LENGTH);
1542 memcpy(newr, host_record, sizeof(dbdata_wait) + host_length);
1543 host_record = newr;
1544 }
1545
1546 /* Now add the new name on the end */
1547
1548 memcpy(host_record->text + host_length, message_id, MESSAGE_ID_LENGTH);
1549 host_record->count++;
1550 host_length += MESSAGE_ID_LENGTH;
1551
1552 /* Update the database */
1553
1554 dbfn_write(dbm_file, host->name, host_record, sizeof(dbdata_wait) + host_length);
7a0743eb 1555 DEBUG(D_transport) debug_printf("added to list for %s\n", host->name);
059ec3d9
PH
1556 }
1557
1558/* All now done */
1559
1560dbfn_close(dbm_file);
1561}
1562
1563
1564
1565
1566/*************************************************
1567* Test for waiting messages *
1568*************************************************/
1569
1570/* This function is called by a remote transport which uses the previous
1571function to remember which messages are waiting for which remote hosts. It's
1572called after a successful delivery and its job is to check whether there is
1573another message waiting for the same host. However, it doesn't do this if the
1574current continue sequence is greater than the maximum supplied as an argument,
1575or greater than the global connection_max_messages, which, if set, overrides.
1576
1577Arguments:
1578 transport_name name of the transport
1579 hostname name of the host
1580 local_message_max maximum number of messages down one connection
1581 as set by the caller transport
1582 new_message_id set to the message id of a waiting message
1583 more set TRUE if there are yet more messages waiting
1584
1585Returns: TRUE if new_message_id set; FALSE otherwise
1586*/
1587
1588BOOL
1589transport_check_waiting(uschar *transport_name, uschar *hostname,
1590 int local_message_max, uschar *new_message_id, BOOL *more)
1591{
1592dbdata_wait *host_record;
1593int host_length, path_len;
1594open_db dbblock;
1595open_db *dbm_file;
1596uschar buffer[256];
1597
1598*more = FALSE;
1599
1600DEBUG(D_transport)
1601 {
1602 debug_printf("transport_check_waiting entered\n");
1603 debug_printf(" sequence=%d local_max=%d global_max=%d\n",
1604 continue_sequence, local_message_max, connection_max_messages);
1605 }
1606
1607/* Do nothing if we have hit the maximum number that can be send down one
1608connection. */
1609
1610if (connection_max_messages >= 0) local_message_max = connection_max_messages;
1611if (local_message_max > 0 && continue_sequence >= local_message_max)
1612 {
1613 DEBUG(D_transport)
1614 debug_printf("max messages for one connection reached: returning\n");
1615 return FALSE;
1616 }
1617
1618/* Open the waiting information database. */
1619
1620sprintf(CS buffer, "wait-%.200s", transport_name);
1621dbm_file = dbfn_open(buffer, O_RDWR, &dbblock, TRUE);
1622if (dbm_file == NULL) return FALSE;
1623
1624/* See if there is a record for this host; if not, there's nothing to do. */
1625
1626host_record = dbfn_read(dbm_file, hostname);
1627if (host_record == NULL)
1628 {
1629 dbfn_close(dbm_file);
1630 DEBUG(D_transport) debug_printf("no messages waiting for %s\n", hostname);
1631 return FALSE;
1632 }
1633
1634/* If the data in the record looks corrupt, just log something and
1635don't try to use it. */
1636
1637if (host_record->count > WAIT_NAME_MAX)
1638 {
1639 dbfn_close(dbm_file);
1640 log_write(0, LOG_MAIN|LOG_PANIC, "smtp-wait database entry for %s has bad "
1641 "count=%d (max=%d)", hostname, host_record->count, WAIT_NAME_MAX);
1642 return FALSE;
1643 }
1644
1645/* Scan the message ids in the record from the end towards the beginning,
1646until one is found for which a spool file actually exists. If the record gets
1647emptied, delete it and continue with any continuation records that may exist.
1648*/
1649
1650host_length = host_record->count * MESSAGE_ID_LENGTH;
1651
1652/* Loop to handle continuation host records in the database */
1653
1654for (;;)
1655 {
1656 BOOL found = FALSE;
1657
1658 sprintf(CS buffer, "%s/input/", spool_directory);
1659 path_len = Ustrlen(buffer);
1660
1661 for (host_length -= MESSAGE_ID_LENGTH; host_length >= 0;
1662 host_length -= MESSAGE_ID_LENGTH)
1663 {
1664 struct stat statbuf;
1665 Ustrncpy(new_message_id, host_record->text + host_length,
1666 MESSAGE_ID_LENGTH);
1667 new_message_id[MESSAGE_ID_LENGTH] = 0;
1668
1669 if (split_spool_directory)
1670 sprintf(CS(buffer + path_len), "%c/%s-D", new_message_id[5], new_message_id);
1671 else
1672 sprintf(CS(buffer + path_len), "%s-D", new_message_id);
1673
1674 /* The listed message may be the one we are currently processing. If
1675 so, we want to remove it from the list without doing anything else.
1676 If not, do a stat to see if it is an existing message. If it is, break
1677 the loop to handle it. No need to bother about locks; as this is all
1678 "hint" processing, it won't matter if it doesn't exist by the time exim
1679 actually tries to deliver it. */
1680
1681 if (Ustrcmp(new_message_id, message_id) != 0 &&
1682 Ustat(buffer, &statbuf) == 0)
1683 {
1684 found = TRUE;
1685 break;
1686 }
1687 }
1688
1689 /* If we have removed all the message ids from the record delete the record.
1690 If there is a continuation record, fetch it and remove it from the file,
1691 as it will be rewritten as the main record. Repeat in the case of an
1692 empty continuation. */
1693
1694 while (host_length <= 0)
1695 {
1696 int i;
1697 dbdata_wait *newr = NULL;
1698
1699 /* Search for a continuation */
1700
1701 for (i = host_record->sequence - 1; i >= 0 && newr == NULL; i--)
1702 {
1703 sprintf(CS buffer, "%.200s:%d", hostname, i);
1704 newr = dbfn_read(dbm_file, buffer);
1705 }
1706
1707 /* If no continuation, delete the current and break the loop */
1708
1709 if (newr == NULL)
1710 {
1711 dbfn_delete(dbm_file, hostname);
1712 break;
1713 }
1714
1715 /* Else replace the current with the continuation */
1716
1717 dbfn_delete(dbm_file, buffer);
1718 host_record = newr;
1719 host_length = host_record->count * MESSAGE_ID_LENGTH;
1720 }
1721
1722 /* If we found an existing message, break the continuation loop. */
1723
1724 if (found) break;
1725
1726 /* If host_length <= 0 we have emptied a record and not found a good message,
1727 and there are no continuation records. Otherwise there is a continuation
1728 record to process. */
1729
1730 if (host_length <= 0)
1731 {
1732 dbfn_close(dbm_file);
1733 DEBUG(D_transport) debug_printf("waiting messages already delivered\n");
1734 return FALSE;
1735 }
1736 }
1737
1738/* Control gets here when an existing message has been encountered; its
1739id is in new_message_id, and host_length is the revised length of the
1740host record. If it is zero, the record has been removed. Update the
1741record if required, close the database, and return TRUE. */
1742
1743if (host_length > 0)
1744 {
1745 host_record->count = host_length/MESSAGE_ID_LENGTH;
1746 dbfn_write(dbm_file, hostname, host_record, (int)sizeof(dbdata_wait) + host_length);
1747 *more = TRUE;
1748 }
1749
1750dbfn_close(dbm_file);
1751return TRUE;
1752}
1753
1754
1755
1756/*************************************************
1757* Deliver waiting message down same socket *
1758*************************************************/
1759
1760/* Fork a new exim process to deliver the message, and do a re-exec, both to
1761get a clean delivery process, and to regain root privilege in cases where it
1762has been given away.
1763
1764Arguments:
1765 transport_name to pass to the new process
1766 hostname ditto
1767 hostaddress ditto
1768 id the new message to process
1769 socket_fd the connected socket
1770
1771Returns: FALSE if fork fails; TRUE otherwise
1772*/
1773
1774BOOL
1775transport_pass_socket(uschar *transport_name, uschar *hostname,
1776 uschar *hostaddress, uschar *id, int socket_fd)
1777{
1778pid_t pid;
1779int status;
1780
1781DEBUG(D_transport) debug_printf("transport_pass_socket entered\n");
1782
1783if ((pid = fork()) == 0)
1784 {
1785 int i = 16;
1786 uschar **argv;
1787
1788 /* Disconnect entirely from the parent process. If we are running in the
1789 test harness, wait for a bit to allow the previous process time to finish,
1790 write the log, etc., so that the output is always in the same order for
1791 automatic comparison. */
1792
1793 if ((pid = fork()) != 0) _exit(EXIT_SUCCESS);
ed0e9820 1794 if (running_in_test_harness) sleep(1);
059ec3d9
PH
1795
1796 /* Set up the calling arguments; use the standard function for the basics,
1797 but we have a number of extras that may be added. */
1798
1799 argv = child_exec_exim(CEE_RETURN_ARGV, TRUE, &i, FALSE, 0);
1800
1801 if (smtp_authenticated) argv[i++] = US"-MCA";
1802
1803 #ifdef SUPPORT_TLS
1804 if (tls_offered) argv[i++] = US"-MCT";
1805 #endif
1806
1807 if (smtp_use_size) argv[i++] = US"-MCS";
1808 if (smtp_use_pipelining) argv[i++] = US"-MCP";
1809
1810 if (queue_run_pid != (pid_t)0)
1811 {
1812 argv[i++] = US"-MCQ";
1813 argv[i++] = string_sprintf("%d", queue_run_pid);
1814 argv[i++] = string_sprintf("%d", queue_run_pipe);
1815 }
1816
1817 argv[i++] = US"-MC";
1818 argv[i++] = transport_name;
1819 argv[i++] = hostname;
1820 argv[i++] = hostaddress;
1821 argv[i++] = string_sprintf("%d", continue_sequence + 1);
1822 argv[i++] = id;
1823 argv[i++] = NULL;
1824
1825 /* Arrange for the channel to be on stdin. */
1826
1827 if (socket_fd != 0)
1828 {
f1e894f3
PH
1829 (void)dup2(socket_fd, 0);
1830 (void)close(socket_fd);
059ec3d9
PH
1831 }
1832
1833 DEBUG(D_exec) debug_print_argv(argv);
1834 exim_nullstd(); /* Ensure std{out,err} exist */
1835 execv(CS argv[0], (char *const *)argv);
1836
1837 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
1838 _exit(errno); /* Note: must be _exit(), NOT exit() */
1839 }
1840
1841/* If the process creation succeeded, wait for the first-level child, which
1842immediately exits, leaving the second level process entirely disconnected from
1843this one. */
1844
1845if (pid > 0)
1846 {
1847 int rc;
1848 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
1849 DEBUG(D_transport) debug_printf("transport_pass_socket succeeded\n");
1850 return TRUE;
1851 }
1852else
1853 {
1854 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
1855 strerror(errno));
1856 return FALSE;
1857 }
1858}
1859
1860
1861
1862/*************************************************
1863* Set up direct (non-shell) command *
1864*************************************************/
1865
1866/* This function is called when a command line is to be parsed and executed
1867directly, without the use of /bin/sh. It is called by the pipe transport,
1868the queryprogram router, and also from the main delivery code when setting up a
1869transport filter process. The code for ETRN also makes use of this; in that
1870case, no addresses are passed.
1871
1872Arguments:
1873 argvptr pointer to anchor for argv vector
1874 cmd points to the command string
1875 expand_arguments true if expansion is to occur
1876 expand_failed error value to set if expansion fails; not relevant if
1877 addr == NULL
1878 addr chain of addresses, or NULL
1879 etext text for use in error messages
1880 errptr where to put error message if addr is NULL;
1881 otherwise it is put in the first address
1882
1883Returns: TRUE if all went well; otherwise an error will be
1884 set in the first address and FALSE returned
1885*/
1886
1887BOOL
1888transport_set_up_command(uschar ***argvptr, uschar *cmd, BOOL expand_arguments,
1889 int expand_failed, address_item *addr, uschar *etext, uschar **errptr)
1890{
1891address_item *ad;
1892uschar **argv;
1893uschar *s, *ss;
1894int address_count = 0;
1895int argcount = 0;
1896int i, max_args;
1897
1898/* Get store in which to build an argument list. Count the number of addresses
1899supplied, and allow for that many arguments, plus an additional 60, which
1900should be enough for anybody. Multiple addresses happen only when the local
1901delivery batch option is set. */
1902
1903for (ad = addr; ad != NULL; ad = ad->next) address_count++;
1904max_args = address_count + 60;
1905*argvptr = argv = store_get((max_args+1)*sizeof(uschar *));
1906
1907/* Split the command up into arguments terminated by white space. Lose
1908trailing space at the start and end. Double-quoted arguments can contain \\ and
1909\" escapes and so can be handled by the standard function; single-quoted
1910arguments are verbatim. Copy each argument into a new string. */
1911
1912s = cmd;
1913while (isspace(*s)) s++;
1914
1915while (*s != 0 && argcount < max_args)
1916 {
1917 if (*s == '\'')
1918 {
1919 ss = s + 1;
1920 while (*ss != 0 && *ss != '\'') ss++;
1921 argv[argcount++] = ss = store_get(ss - s++);
1922 while (*s != 0 && *s != '\'') *ss++ = *s++;
1923 if (*s != 0) s++;
1924 *ss++ = 0;
1925 }
1926 else argv[argcount++] = string_dequote(&s);
1927 while (isspace(*s)) s++;
1928 }
1929
1930argv[argcount] = (uschar *)0;
1931
1932/* If *s != 0 we have run out of argument slots. */
1933
1934if (*s != 0)
1935 {
1936 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
1937 "%s", cmd, etext);
1938 if (addr != NULL)
1939 {
1940 addr->transport_return = FAIL;
1941 addr->message = msg;
1942 }
1943 else *errptr = msg;
1944 return FALSE;
1945 }
1946
1947/* Expand each individual argument if required. Expansion happens for pipes set
1948up in filter files and with directly-supplied commands. It does not happen if
1949the pipe comes from a traditional .forward file. A failing expansion is a big
1950disaster if the command came from Exim's configuration; if it came from a user
1951it is just a normal failure. The expand_failed value is used as the error value
1952to cater for these two cases.
1953
1954An argument consisting just of the text "$pipe_addresses" is treated specially.
1955It is not passed to the general expansion function. Instead, it is replaced by
1956a number of arguments, one for each address. This avoids problems with shell
1957metacharacters and spaces in addresses.
1958
1959If the parent of the top address has an original part of "system-filter", this
1960pipe was set up by the system filter, and we can permit the expansion of
1961$recipients. */
1962
1963DEBUG(D_transport)
1964 {
1965 debug_printf("direct command:\n");
1966 for (i = 0; argv[i] != (uschar *)0; i++)
1967 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
1968 }
1969
1970if (expand_arguments)
1971 {
1972 BOOL allow_dollar_recipients = addr != NULL &&
1973 addr->parent != NULL &&
1974 Ustrcmp(addr->parent->address, "system-filter") == 0;
1975
1976 for (i = 0; argv[i] != (uschar *)0; i++)
1977 {
1978
1979 /* Handle special fudge for passing an address list */
1980
1981 if (addr != NULL &&
1982 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
1983 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
1984 {
1985 int additional;
1986
1987 if (argcount + address_count - 1 > max_args)
1988 {
1989 addr->transport_return = FAIL;
1990 addr->message = string_sprintf("Too many arguments to command \"%s\" "
1991 "in %s", cmd, etext);
1992 return FALSE;
1993 }
1994
1995 additional = address_count - 1;
1996 if (additional > 0)
1997 memmove(argv + i + 1 + additional, argv + i + 1,
1998 (argcount - i)*sizeof(uschar *));
1999
2000 for (ad = addr; ad != NULL; ad = ad->next) argv[i++] = ad->address;
2001 i--;
2002 }
2003
2004 /* Handle normal expansion string */
2005
2006 else
2007 {
2008 uschar *expanded_arg;
2009 enable_dollar_recipients = allow_dollar_recipients;
2010 expanded_arg = expand_string(argv[i]);
2011 enable_dollar_recipients = FALSE;
2012
2013 if (expanded_arg == NULL)
2014 {
2015 uschar *msg = string_sprintf("Expansion of \"%s\" "
2016 "from command \"%s\" in %s failed: %s",
2017 argv[i], cmd, etext, expand_string_message);
2018 if (addr != NULL)
2019 {
2020 addr->transport_return = expand_failed;
2021 addr->message = msg;
2022 }
2023 else *errptr = msg;
2024 return FALSE;
2025 }
2026 argv[i] = expanded_arg;
2027 }
2028 }
2029
2030 DEBUG(D_transport)
2031 {
2032 debug_printf("direct command after expansion:\n");
2033 for (i = 0; argv[i] != (uschar *)0; i++)
2034 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2035 }
2036 }
2037
2038return TRUE;
2039}
2040
2041/* End of transport.c */