1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* Copyright (c) The Exim Maintainers 2020 */
7 /* See the file NOTICE for conditions of use and distribution. */
8
9 /* General functions concerned with transportation, and generic options for all
10 transports. */
11
12
13 #include "exim.h"
14
15 /* Generic options for transports, all of which live inside transport_instance
16 data blocks and which therefore have the opt_public flag set. Note that there
17 are other options living inside this structure which can be set only from
18 certain transports. */
19 #define LOFF(field) OPT_OFF(transport_instance, field)
20
21 optionlist optionlist_transports[] = {
22 /* name type value */
23 { "*expand_group", opt_stringptr|opt_hidden|opt_public,
24 LOFF(expand_gid) },
25 { "*expand_user", opt_stringptr|opt_hidden|opt_public,
26 LOFF(expand_uid) },
27 { "*headers_rewrite_flags", opt_int|opt_public|opt_hidden,
28 LOFF(rewrite_existflags) },
29 { "*headers_rewrite_rules", opt_void|opt_public|opt_hidden,
30 LOFF(rewrite_rules) },
31 { "*set_group", opt_bool|opt_hidden|opt_public,
32 LOFF(gid_set) },
33 { "*set_user", opt_bool|opt_hidden|opt_public,
34 LOFF(uid_set) },
35 { "body_only", opt_bool|opt_public,
36 LOFF(body_only) },
37 { "current_directory", opt_stringptr|opt_public,
38 LOFF(current_dir) },
39 { "debug_print", opt_stringptr | opt_public,
40 LOFF(debug_string) },
41 { "delivery_date_add", opt_bool|opt_public,
42 LOFF(delivery_date_add) },
43 { "disable_logging", opt_bool|opt_public,
44 LOFF(disable_logging) },
45 { "driver", opt_stringptr|opt_public,
46 LOFF(driver_name) },
47 { "envelope_to_add", opt_bool|opt_public,
48 LOFF(envelope_to_add) },
49 #ifndef DISABLE_EVENT
50 { "event_action", opt_stringptr | opt_public,
51 LOFF(event_action) },
52 #endif
53 { "group", opt_expand_gid|opt_public,
54 LOFF(gid) },
55 { "headers_add", opt_stringptr|opt_public|opt_rep_str,
56 LOFF(add_headers) },
57 { "headers_only", opt_bool|opt_public,
58 LOFF(headers_only) },
59 { "headers_remove", opt_stringptr|opt_public|opt_rep_str,
60 LOFF(remove_headers) },
61 { "headers_rewrite", opt_rewrite|opt_public,
62 LOFF(headers_rewrite) },
63 { "home_directory", opt_stringptr|opt_public,
64 LOFF(home_dir) },
65 { "initgroups", opt_bool|opt_public,
66 LOFF(initgroups) },
67 { "max_parallel", opt_stringptr|opt_public,
68 LOFF(max_parallel) },
69 { "message_size_limit", opt_stringptr|opt_public,
70 LOFF(message_size_limit) },
71 { "rcpt_include_affixes", opt_bool|opt_public,
72 LOFF(rcpt_include_affixes) },
73 { "retry_use_local_part", opt_bool|opt_public,
74 LOFF(retry_use_local_part) },
75 { "return_path", opt_stringptr|opt_public,
76 LOFF(return_path) },
77 { "return_path_add", opt_bool|opt_public,
78 LOFF(return_path_add) },
79 { "shadow_condition", opt_stringptr|opt_public,
80 LOFF(shadow_condition) },
81 { "shadow_transport", opt_stringptr|opt_public,
82 LOFF(shadow) },
83 { "transport_filter", opt_stringptr|opt_public,
84 LOFF(filter_command) },
85 { "transport_filter_timeout", opt_time|opt_public,
86 LOFF(filter_timeout) },
87 { "user", opt_expand_uid|opt_public,
88 LOFF(uid) }
89 };
90
91 int optionlist_transports_size = nelem(optionlist_transports);
92
93 #ifdef MACRO_PREDEF
94
95 # include "macro_predef.h"
96
97 void
options_transports(void)98 options_transports(void)
99 {
100 uschar buf[64];
101
102 options_from_list(optionlist_transports, nelem(optionlist_transports), US"TRANSPORTS", NULL);
103
104 for (transport_info * ti = transports_available; ti->driver_name[0]; ti++)
105 {
106 spf(buf, sizeof(buf), US"_DRIVER_TRANSPORT_%T", ti->driver_name);
107 builtin_macro_create(buf);
108 options_from_list(ti->options, (unsigned)*ti->options_count, US"TRANSPORT", ti->driver_name);
109 }
110 }
111
112 #else /*!MACRO_PREDEF*/
113
114 /* Structure for keeping list of addresses that have been added to
115 Envelope-To:, in order to avoid duplication. */
116
117 struct aci {
118 struct aci *next;
119 address_item *ptr;
120 };
121
122
123 /* Static data for write_chunk() */
124
125 static uschar *chunk_ptr; /* chunk pointer */
126 static uschar *nl_check; /* string to look for at line start */
127 static int nl_check_length; /* length of same */
128 static uschar *nl_escape; /* string to insert */
129 static int nl_escape_length; /* length of same */
130 static int nl_partial_match; /* length matched at chunk end */
131
132
133 /*************************************************
134 * Initialize transport list *
135 *************************************************/
136
137 /* Read the transports section of the configuration file, and set up a chain of
138 transport instances according to its contents. Each transport has generic
139 options and may also have its own private options. This function is only ever
140 called when transports == NULL. We use generic code in readconf to do most of
141 the work. */
142
143 void
transport_init(void)144 transport_init(void)
145 {
146 readconf_driver_init(US"transport",
147 (driver_instance **)(&transports), /* chain anchor */
148 (driver_info *)transports_available, /* available drivers */
149 sizeof(transport_info), /* size of info block */
150 &transport_defaults, /* default values for generic options */
151 sizeof(transport_instance), /* size of instance block */
152 optionlist_transports, /* generic options */
153 optionlist_transports_size);
154
155 /* Now scan the configured transports and check inconsistencies. A shadow
156 transport is permitted only for local transports. */
157
158 for (transport_instance * t = transports; t; t = t->next)
159 {
160 if (!t->info->local && t->shadow)
161 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
162 "shadow transport not allowed on non-local transport %s", t->name);
163
164 if (t->body_only && t->headers_only)
165 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
166 "%s transport: body_only and headers_only are mutually exclusive",
167 t->name);
168 }
169 }
170
171
172
173 /*************************************************
174 * Write block of data *
175 *************************************************/
176
177 static int
tpt_write(int fd,uschar * block,int len,BOOL more,int options)178 tpt_write(int fd, uschar * block, int len, BOOL more, int options)
179 {
180 return
181 #ifndef DISABLE_TLS
182 tls_out.active.sock == fd
183 ? tls_write(tls_out.active.tls_ctx, block, len, more) :
184 #endif
185 #ifdef MSG_MORE
186 more && !(options & topt_not_socket) ? send(fd, block, len, MSG_MORE) :
187 #endif
188 write(fd, block, len);
189 }
190
191 /* Subroutine called by write_chunk() and at the end of the message actually
192 to write a data block. Also called directly by some transports to write
193 additional data to the file descriptor (e.g. prefix, suffix).
194
195 If a transport wants data transfers to be timed, it sets a non-zero value in
196 transport_write_timeout. A non-zero transport_write_timeout causes a timer to
197 be set for each block of data written from here. If time runs out, then write()
198 fails and provokes an error return. The caller can then inspect sigalrm_seen to
199 check for a timeout.
200
201 On some systems, if a quota is exceeded during the write, the yield is the
202 number of bytes written rather than an immediate error code. This also happens
203 on some systems in other cases, for example a pipe that goes away because the
204 other end's process terminates (Linux). On other systems, (e.g. Solaris 2) you
205 get the error codes the first time.
206
207 The write() function is also interruptible; the Solaris 2.6 man page says:
208
209 If write() is interrupted by a signal before it writes any
210 data, it will return -1 with errno set to EINTR.
211
212 If write() is interrupted by a signal after it successfully
213 writes some data, it will return the number of bytes written.
214
215 To handle these cases, we want to restart the write() to output the remainder
216 of the data after a non-negative return from write(), except after a timeout.
217 In the error cases (EDQUOT, EPIPE) no bytes get written the second time, and a
218 proper error then occurs. In principle, after an interruption, the second
219 write() could suffer the same fate, but we do not want to continue for
220 evermore, so stick a maximum repetition count on the loop to act as a
221 longstop.
222
223 Arguments:
224 tctx transport context: file descriptor or string to write to
225 block block of bytes to write
226 len number of bytes to write
227 more further data expected soon
228
229 Returns: TRUE on success, FALSE on failure (with errno preserved);
230 transport_count is incremented by the number of bytes written
231 */
232
233 static BOOL
transport_write_block_fd(transport_ctx * tctx,uschar * block,int len,BOOL more)234 transport_write_block_fd(transport_ctx * tctx, uschar * block, int len, BOOL more)
235 {
236 int rc, save_errno;
237 int local_timeout = transport_write_timeout;
238 int connretry = 1;
239 int fd = tctx->u.fd;
240
241 /* This loop is for handling incomplete writes and other retries. In most
242 normal cases, it is only ever executed once. */
243
244 for (int i = 0; i < 100; i++)
245 {
246 DEBUG(D_transport)
247 debug_printf("writing data block fd=%d size=%d timeout=%d%s\n",
248 fd, len, local_timeout, more ? " (more expected)" : "");
249
250 /* When doing TCP Fast Open we may get this far before the 3-way handshake
251 is complete, and write returns ENOTCONN. Detect that, wait for the socket
252 to become writable, and retry once only. */
253
254 for(;;)
255 {
256 /* This code makes use of alarm() in order to implement the timeout. This
257 isn't a very tidy way of doing things. Using non-blocking I/O with select()
258 provides a neater approach. However, I don't know how to do this when TLS is
259 in use. */
260
261 if (transport_write_timeout <= 0) /* No timeout wanted */
262 {
263 rc = tpt_write(fd, block, len, more, tctx->options);
264 save_errno = errno;
265 }
266 else /* Timeout wanted. */
267 {
268 sigalrm_seen = FALSE;
269 ALARM(local_timeout);
270 rc = tpt_write(fd, block, len, more, tctx->options);
271 save_errno = errno;
272 local_timeout = ALARM_CLR(0);
273 if (sigalrm_seen)
274 {
275 errno = ETIMEDOUT;
276 return FALSE;
277 }
278 }
279
280 if (rc >= 0 || errno != ENOTCONN || connretry <= 0)
281 break;
282
283 poll_one_fd(fd, POLLOUT, -1); /* could set timeout? retval check? */
284 connretry--;
285 }
286
287 /* Hopefully, the most common case is success, so test that first. */
288
289 if (rc == len) { transport_count += len; return TRUE; }
290
291 /* A non-negative return code is an incomplete write. Try again for the rest
292 of the block. If we have exactly hit the timeout, give up. */
293
294 if (rc >= 0)
295 {
296 len -= rc;
297 block += rc;
298 transport_count += rc;
299 DEBUG(D_transport) debug_printf("write incomplete (%d)\n", rc);
300 goto CHECK_TIMEOUT; /* A few lines below */
301 }
302
303 /* A negative return code with an EINTR error is another form of
304 incomplete write, zero bytes having been written */
305
306 if (save_errno == EINTR)
307 {
308 DEBUG(D_transport)
309 debug_printf("write interrupted before anything written\n");
310 goto CHECK_TIMEOUT; /* A few lines below */
311 }
312
313 /* A response of EAGAIN from write() is likely only in the case of writing
314 to a FIFO that is not swallowing the data as fast as Exim is writing it. */
315
316 if (save_errno == EAGAIN)
317 {
318 DEBUG(D_transport)
319 debug_printf("write temporarily locked out, waiting 1 sec\n");
320 sleep(1);
321
322 /* Before continuing to try another write, check that we haven't run out of
323 time. */
324
325 CHECK_TIMEOUT:
326 if (transport_write_timeout > 0 && local_timeout <= 0)
327 {
328 errno = ETIMEDOUT;
329 return FALSE;
330 }
331 continue;
332 }
333
334 /* Otherwise there's been an error */
335
336 DEBUG(D_transport) debug_printf("writing error %d: %s\n", save_errno,
337 strerror(save_errno));
338 errno = save_errno;
339 return FALSE;
340 }
341
342 /* We've tried and tried and tried but still failed */
343
344 errno = ERRNO_WRITEINCOMPLETE;
345 return FALSE;
346 }
347
348
349 BOOL
transport_write_block(transport_ctx * tctx,uschar * block,int len,BOOL more)350 transport_write_block(transport_ctx * tctx, uschar *block, int len, BOOL more)
351 {
352 if (!(tctx->options & topt_output_string))
353 return transport_write_block_fd(tctx, block, len, more);
354
355 /* Write to expanding-string. NOTE: not NUL-terminated */
356
357 if (!tctx->u.msg)
358 tctx->u.msg = string_get(1024);
359
360 tctx->u.msg = string_catn(tctx->u.msg, block, len);
361 return TRUE;
362 }
363
364
365
366
367 /*************************************************
368 * Write formatted string *
369 *************************************************/
370
371 /* This is called by various transports. It is a convenience function.
372
373 Arguments:
374 fd file descriptor
375 format string format
376 ... arguments for format
377
378 Returns: the yield of transport_write_block()
379 */
380
381 BOOL
transport_write_string(int fd,const char * format,...)382 transport_write_string(int fd, const char *format, ...)
383 {
384 transport_ctx tctx = {{0}};
385 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer };
386 va_list ap;
387
388 /* Use taint-unchecked routines for writing into big_buffer, trusting
389 that the result will never be expanded. */
390
391 va_start(ap, format);
392 if (!string_vformat(&gs, SVFMT_TAINT_NOCHK, format, ap))
393 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "overlong formatted string in transport");
394 va_end(ap);
395 tctx.u.fd = fd;
396 return transport_write_block(&tctx, gs.s, gs.ptr, FALSE);
397 }
398
399
400
401
402 void
transport_write_reset(int options)403 transport_write_reset(int options)
404 {
405 if (!(options & topt_continuation)) chunk_ptr = deliver_out_buffer;
406 nl_partial_match = -1;
407 nl_check_length = nl_escape_length = 0;
408 }
409
410
411
412 /*************************************************
413 * Write character chunk *
414 *************************************************/
415
416 /* Subroutine used by transport_write_message() to scan character chunks for
417 newlines and act appropriately. The object is to minimise the number of writes.
418 The output byte stream is buffered up in deliver_out_buffer, which is written
419 only when it gets full, thus minimizing write operations and TCP packets.
420
421 Static data is used to handle the case when the last character of the previous
422 chunk was NL, or matched part of the data that has to be escaped.
423
424 Arguments:
425 tctx transport context - processing to be done during output,
426 and file descriptor to write to
427 chunk pointer to data to write
428 len length of data to write
429
430 In addition, the static nl_xxx variables must be set as required.
431
432 Returns: TRUE on success, FALSE on failure (with errno preserved)
433 */
434
435 BOOL
write_chunk(transport_ctx * tctx,uschar * chunk,int len)436 write_chunk(transport_ctx * tctx, uschar *chunk, int len)
437 {
438 uschar *start = chunk;
439 uschar *end = chunk + len;
440 int mlen = DELIVER_OUT_BUFFER_SIZE - nl_escape_length - 2;
441
442 /* The assumption is made that the check string will never stretch over move
443 than one chunk since the only time there are partial matches is when copying
444 the body in large buffers. There is always enough room in the buffer for an
445 escape string, since the loop below ensures this for each character it
446 processes, and it won't have stuck in the escape string if it left a partial
447 match. */
448
449 if (nl_partial_match >= 0)
450 {
451 if (nl_check_length > 0 && len >= nl_check_length &&
452 Ustrncmp(start, nl_check + nl_partial_match,
453 nl_check_length - nl_partial_match) == 0)
454 {
455 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
456 chunk_ptr += nl_escape_length;
457 start += nl_check_length - nl_partial_match;
458 }
459
460 /* The partial match was a false one. Insert the characters carried over
461 from the previous chunk. */
462
463 else if (nl_partial_match > 0)
464 {
465 Ustrncpy(chunk_ptr, nl_check, nl_partial_match);
466 chunk_ptr += nl_partial_match;
467 }
468
469 nl_partial_match = -1;
470 }
471
472 /* Now process the characters in the chunk. Whenever we hit a newline we check
473 for possible escaping. The code for the non-NL route should be as fast as
474 possible. */
475
476 for (uschar * ptr = start; ptr < end; ptr++)
477 {
478 int ch, len;
479
480 /* Flush the buffer if it has reached the threshold - we want to leave enough
481 room for the next uschar, plus a possible extra CR for an LF, plus the escape
482 string. */
483
484 if ((len = chunk_ptr - deliver_out_buffer) > mlen)
485 {
486 DEBUG(D_transport) debug_printf("flushing headers buffer\n");
487
488 /* If CHUNKING, prefix with BDAT (size) NON-LAST. Also, reap responses
489 from previous SMTP commands. */
490
491 if (tctx->options & topt_use_bdat && tctx->chunk_cb)
492 {
493 if ( tctx->chunk_cb(tctx, (unsigned)len, 0) != OK
494 || !transport_write_block(tctx, deliver_out_buffer, len, FALSE)
495 || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
496 )
497 return FALSE;
498 }
499 else
500 if (!transport_write_block(tctx, deliver_out_buffer, len, FALSE))
501 return FALSE;
502 chunk_ptr = deliver_out_buffer;
503 }
504
505 /* Remove CR before NL if required */
506
507 if ( *ptr == '\r' && ptr[1] == '\n'
508 && !(tctx->options & topt_use_crlf)
509 && f.spool_file_wireformat
510 )
511 ptr++;
512
513 if ((ch = *ptr) == '\n')
514 {
515 int left = end - ptr - 1; /* count of chars left after NL */
516
517 /* Insert CR before NL if required */
518
519 if (tctx->options & topt_use_crlf && !f.spool_file_wireformat)
520 *chunk_ptr++ = '\r';
521 *chunk_ptr++ = '\n';
522 transport_newlines++;
523
524 /* The check_string test (formerly "from hack") replaces the specific
525 string at the start of a line with an escape string (e.g. "From " becomes
526 ">From " or "." becomes "..". It is a case-sensitive test. The length
527 check above ensures there is always enough room to insert this string. */
528
529 if (nl_check_length > 0)
530 {
531 if (left >= nl_check_length &&
532 Ustrncmp(ptr+1, nl_check, nl_check_length) == 0)
533 {
534 Ustrncpy(chunk_ptr, nl_escape, nl_escape_length);
535 chunk_ptr += nl_escape_length;
536 ptr += nl_check_length;
537 }
538
539 /* Handle the case when there isn't enough left to match the whole
540 check string, but there may be a partial match. We remember how many
541 characters matched, and finish processing this chunk. */
542
543 else if (left <= 0) nl_partial_match = 0;
544
545 else if (Ustrncmp(ptr+1, nl_check, left) == 0)
546 {
547 nl_partial_match = left;
548 ptr = end;
549 }
550 }
551 }
552
553 /* Not a NL character */
554
555 else *chunk_ptr++ = ch;
556 }
557
558 return TRUE;
559 }
560
561
562
563
564 /*************************************************
565 * Generate address for RCPT TO *
566 *************************************************/
567
568 /* This function puts together an address for RCPT to, using the caseful
569 version of the local part and the caseful version of the domain. If there is no
570 prefix or suffix, or if affixes are to be retained, we can just use the
571 original address. Otherwise, if there is a prefix but no suffix we can use a
572 pointer into the original address. If there is a suffix, however, we have to
573 build a new string.
574
575 Arguments:
576 addr the address item
577 include_affixes TRUE if affixes are to be included
578
579 Returns: a string
580 */
581
582 uschar *
transport_rcpt_address(address_item * addr,BOOL include_affixes)583 transport_rcpt_address(address_item *addr, BOOL include_affixes)
584 {
585 uschar *at;
586 int plen, slen;
587
588 if (include_affixes)
589 {
590 setflag(addr, af_include_affixes); /* Affects logged => line */
591 return addr->address;
592 }
593
594 if (!addr->suffix)
595 {
596 if (!addr->prefix) return addr->address;
597 return addr->address + Ustrlen(addr->prefix);
598 }
599
600 at = Ustrrchr(addr->address, '@');
601 plen = addr->prefix ? Ustrlen(addr->prefix) : 0;
602 slen = Ustrlen(addr->suffix);
603
604 return string_sprintf("%.*s@%s", (int)(at - addr->address - plen - slen),
605 addr->address + plen, at + 1);
606 }
607
608
609 /*************************************************
610 * Output Envelope-To: address & scan duplicates *
611 *************************************************/
612
613 /* This function is called from internal_transport_write_message() below, when
614 generating an Envelope-To: header line. It checks for duplicates of the given
615 address and its ancestors. When one is found, this function calls itself
616 recursively, to output the envelope address of the duplicate.
617
618 We want to avoid duplication in the list, which can arise for example when
619 A->B,C and then both B and C alias to D. This can also happen when there are
620 unseen drivers in use. So a list of addresses that have been output is kept in
621 the plist variable.
622
623 It is also possible to have loops in the address ancestry/duplication graph,
624 for example if there are two top level addresses A and B and we have A->B,C and
625 B->A. To break the loop, we use a list of processed addresses in the dlist
626 variable.
627
628 After handling duplication, this function outputs the progenitor of the given
629 address.
630
631 Arguments:
632 p the address we are interested in
633 pplist address of anchor of the list of addresses not to output
634 pdlist address of anchor of the list of processed addresses
635 first TRUE if this is the first address; set it FALSE afterwards
636 tctx transport context - processing to be done during output
637 and the file descriptor to write to
638
639 Returns: FALSE if writing failed
640 */
641
642 static BOOL
write_env_to(address_item * p,struct aci ** pplist,struct aci ** pdlist,BOOL * first,transport_ctx * tctx)643 write_env_to(address_item *p, struct aci **pplist, struct aci **pdlist,
644 BOOL *first, transport_ctx * tctx)
645 {
646 address_item *pp;
647 struct aci *ppp;
648
649 /* Do nothing if we have already handled this address. If not, remember it
650 so that we don't handle it again. */
651
652 for (ppp = *pdlist; ppp; ppp = ppp->next) if (p == ppp->ptr) return TRUE;
653
654 ppp = store_get(sizeof(struct aci), FALSE);
655 ppp->next = *pdlist;
656 *pdlist = ppp;
657 ppp->ptr = p;
658
659 /* Now scan up the ancestry, checking for duplicates at each generation. */
660
661 for (pp = p;; pp = pp->parent)
662 {
663 address_item *dup;
664 for (dup = addr_duplicate; dup; dup = dup->next)
665 if (dup->dupof == pp) /* a dup of our address */
666 if (!write_env_to(dup, pplist, pdlist, first, tctx))
667 return FALSE;
668 if (!pp->parent) break;
669 }
670
671 /* Check to see if we have already output the progenitor. */
672
673 for (ppp = *pplist; ppp; ppp = ppp->next) if (pp == ppp->ptr) break;
674 if (ppp) return TRUE;
675
676 /* Remember what we have output, and output it. */
677
678 ppp = store_get(sizeof(struct aci), FALSE);
679 ppp->next = *pplist;
680 *pplist = ppp;
681 ppp->ptr = pp;
682
683 if (!*first && !write_chunk(tctx, US",\n ", 3)) return FALSE;
684 *first = FALSE;
685 return write_chunk(tctx, pp->address, Ustrlen(pp->address));
686 }
687
688
689
690
691 /* Add/remove/rewrite headers, and send them plus the empty-line separator.
692
693 Globals:
694 header_list
695
696 Arguments:
697 addr (chain of) addresses (for extra headers), or NULL;
698 only the first address is used
699 tctx transport context
700 sendfn function for output (transport or verify)
701
702 Returns: TRUE on success; FALSE on failure.
703 */
704 BOOL
transport_headers_send(transport_ctx * tctx,BOOL (* sendfn)(transport_ctx * tctx,uschar * s,int len))705 transport_headers_send(transport_ctx * tctx,
706 BOOL (*sendfn)(transport_ctx * tctx, uschar * s, int len))
707 {
708 const uschar *list;
709 transport_instance * tblock = tctx ? tctx->tblock : NULL;
710 address_item * addr = tctx ? tctx->addr : NULL;
711
712 /* Then the message's headers. Don't write any that are flagged as "old";
713 that means they were rewritten, or are a record of envelope rewriting, or
714 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
715 match any entries therein. It is a colon-sep list; expand the items
716 separately and squash any empty ones.
717 Then check addr->prop.remove_headers too, provided that addr is not NULL. */
718
719 for (header_line * h = header_list; h; h = h->next) if (h->type != htype_old)
720 {
721 BOOL include_header = TRUE;
722
723 list = tblock ? tblock->remove_headers : NULL;
724 for (int i = 0; i < 2; i++) /* For remove_headers && addr->prop.remove_headers */
725 {
726 if (list)
727 {
728 int sep = ':'; /* This is specified as a colon-separated list */
729 uschar *s, *ss;
730 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
731 {
732 int len;
733
734 if (i == 0)
735 if (!(s = expand_string(s)) && !f.expand_string_forcedfail)
736 {
737 errno = ERRNO_CHHEADER_FAIL;
738 return FALSE;
739 }
740 len = s ? Ustrlen(s) : 0;
741 if (len && s[len-1] == '*') /* trailing glob */
742 {
743 if (strncmpic(h->text, s, len-1) == 0) break;
744 }
745 else
746 {
747 if (strncmpic(h->text, s, len) != 0) continue;
748 ss = h->text + len;
749 while (*ss == ' ' || *ss == '\t') ss++;
750 if (*ss == ':') break;
751 }
752 }
753 if (s) { include_header = FALSE; break; }
754 }
755 if (addr) list = addr->prop.remove_headers;
756 }
757
758 /* If this header is to be output, try to rewrite it if there are rewriting
759 rules. */
760
761 if (include_header)
762 {
763 if (tblock && tblock->rewrite_rules)
764 {
765 rmark reset_point = store_mark();
766 header_line *hh;
767
768 if ((hh = rewrite_header(h, NULL, NULL, tblock->rewrite_rules,
769 tblock->rewrite_existflags, FALSE)))
770 {
771 if (!sendfn(tctx, hh->text, hh->slen)) return FALSE;
772 store_reset(reset_point);
773 continue; /* With the next header line */
774 }
775 }
776
777 /* Either no rewriting rules, or it didn't get rewritten */
778
779 if (!sendfn(tctx, h->text, h->slen)) return FALSE;
780 }
781
782 /* Header removed */
783
784 else
785 DEBUG(D_transport) debug_printf("removed header line:\n%s---\n", h->text);
786 }
787
788 /* Add on any address-specific headers. If there are multiple addresses,
789 they will all have the same headers in order to be batched. The headers
790 are chained in reverse order of adding (so several addresses from the
791 same alias might share some of them) but we want to output them in the
792 opposite order. This is a bit tedious, but there shouldn't be very many
793 of them. We just walk the list twice, reversing the pointers each time,
794 but on the second time, write out the items.
795
796 Headers added to an address by a router are guaranteed to end with a newline.
797 */
798
799 if (addr)
800 {
801 header_line *hprev = addr->prop.extra_headers;
802 header_line *hnext, * h;
803 for (int i = 0; i < 2; i++)
804 for (h = hprev, hprev = NULL; h; h = hnext)
805 {
806 hnext = h->next;
807 h->next = hprev;
808 hprev = h;
809 if (i == 1)
810 {
811 if (!sendfn(tctx, h->text, h->slen)) return FALSE;
812 DEBUG(D_transport)
813 debug_printf("added header line(s):\n%s---\n", h->text);
814 }
815 }
816 }
817
818 /* If a string containing additional headers exists it is a newline-sep
819 list. Expand each item and write out the result. This is done last so that
820 if it (deliberately or accidentally) isn't in header format, it won't mess
821 up any other headers. An empty string or a forced expansion failure are
822 noops. An added header string from a transport may not end with a newline;
823 add one if it does not. */
824
825 if (tblock && (list = CUS tblock->add_headers))
826 {
827 int sep = '\n';
828 uschar * s;
829
830 while ((s = string_nextinlist(&list, &sep, NULL, 0)))
831 if ((s = expand_string(s)))
832 {
833 int len = Ustrlen(s);
834 if (len > 0)
835 {
836 if (!sendfn(tctx, s, len)) return FALSE;
837 if (s[len-1] != '\n' && !sendfn(tctx, US"\n", 1))
838 return FALSE;
839 DEBUG(D_transport)
840 {
841 debug_printf("added header line:\n%s", s);
842 if (s[len-1] != '\n') debug_printf("\n");
843 debug_printf("---\n");
844 }
845 }
846 }
847 else if (!f.expand_string_forcedfail)
848 { errno = ERRNO_CHHEADER_FAIL; return FALSE; }
849 }
850
851 /* Separate headers from body with a blank line */
852
853 return sendfn(tctx, US"\n", 1);
854 }
855
856
857 /*************************************************
858 * Write the message *
859 *************************************************/
860
861 /* This function writes the message to the given file descriptor. The headers
862 are in the in-store data structure, and the rest of the message is in the open
863 file descriptor deliver_datafile. Make sure we start it at the beginning.
864
865 . If add_return_path is TRUE, a "return-path:" header is added to the message,
866 containing the envelope sender's address.
867
868 . If add_envelope_to is TRUE, a "envelope-to:" header is added to the message,
869 giving the top-level envelope address that caused this delivery to happen.
870
871 . If add_delivery_date is TRUE, a "delivery-date:" header is added to the
872 message. It gives the time and date that delivery took place.
873
874 . If check_string is not null, the start of each line is checked for that
875 string. If it is found, it is replaced by escape_string. This used to be
876 the "from hack" for files, and "smtp_dots" for escaping SMTP dots.
877
878 . If use_crlf is true, newlines are turned into CRLF (SMTP output).
879
880 The yield is TRUE if all went well, and FALSE if not. Exit *immediately* after
881 any writing or reading error, leaving the code in errno intact. Error exits
882 can include timeouts for certain transports, which are requested by setting
883 transport_write_timeout non-zero.
884
885 Arguments:
886 tctx
887 (fd, msg) Either an fd, to write the message to,
888 or a string: if null write message to allocated space
889 otherwire take content as headers.
890 addr (chain of) addresses (for extra headers), or NULL;
891 only the first address is used
892 tblock optional transport instance block (NULL signifies NULL/0):
893 add_headers a string containing one or more headers to add; it is
894 expanded, and must be in correct RFC 822 format as
895 it is transmitted verbatim; NULL => no additions,
896 and so does empty string or forced expansion fail
897 remove_headers a colon-separated list of headers to remove, or NULL
898 rewrite_rules chain of header rewriting rules
899 rewrite_existflags flags for the rewriting rules
900 options bit-wise options:
901 add_return_path if TRUE, add a "return-path" header
902 add_envelope_to if TRUE, add a "envelope-to" header
903 add_delivery_date if TRUE, add a "delivery-date" header
904 use_crlf if TRUE, turn NL into CR LF
905 end_dot if TRUE, send a terminating "." line at the end
906 no_flush if TRUE, do not flush at end
907 no_headers if TRUE, omit the headers
908 no_body if TRUE, omit the body
909 check_string a string to check for at the start of lines, or NULL
910 escape_string a string to insert in front of any check string
911 size_limit if > 0, this is a limit to the size of message written;
912 it is used when returning messages to their senders,
913 and is approximate rather than exact, owing to chunk
914 buffering
915
916 Returns: TRUE on success; FALSE (with errno) on failure.
917 In addition, the global variable transport_count
918 is incremented by the number of bytes written.
919 */
920
921 static BOOL
internal_transport_write_message(transport_ctx * tctx,int size_limit)922 internal_transport_write_message(transport_ctx * tctx, int size_limit)
923 {
924 int len, size = 0;
925
926 /* Initialize pointer in output buffer. */
927
928 transport_write_reset(tctx->options);
929
930 /* Set up the data for start-of-line data checking and escaping */
931
932 if (tctx->check_string && tctx->escape_string)
933 {
934 nl_check = tctx->check_string;
935 nl_check_length = Ustrlen(nl_check);
936 nl_escape = tctx->escape_string;
937 nl_escape_length = Ustrlen(nl_escape);
938 }
939
940 /* Whether the escaping mechanism is applied to headers or not is controlled by
941 an option (set for SMTP, not otherwise). Negate the length if not wanted till
942 after the headers. */
943
944 if (!(tctx->options & topt_escape_headers))
945 nl_check_length = -nl_check_length;
946
947 /* Write the headers if required, including any that have to be added. If there
948 are header rewriting rules, apply them. The datasource is not the -D spoolfile
949 so temporarily hide the global that adjusts for its format. */
950
951 if (!(tctx->options & topt_no_headers))
952 {
953 BOOL save_wireformat = f.spool_file_wireformat;
954 f.spool_file_wireformat = FALSE;
955
956 /* Add return-path: if requested. */
957
958 if (tctx->options & topt_add_return_path)
959 {
960 int n;
961 uschar * s = string_sprintf("Return-path: <%.*s>\n%n",
962 EXIM_EMAILADDR_MAX, return_path, &n);
963 if (!write_chunk(tctx, s, n)) goto bad;
964 }
965
966 /* Add envelope-to: if requested */
967
968 if (tctx->options & topt_add_envelope_to)
969 {
970 BOOL first = TRUE;
971 struct aci *plist = NULL;
972 struct aci *dlist = NULL;
973 rmark reset_point = store_mark();
974
975 if (!write_chunk(tctx, US"Envelope-to: ", 13)) goto bad;
976
977 /* Pick up from all the addresses. The plist and dlist variables are
978 anchors for lists of addresses already handled; they have to be defined at
979 this level because write_env_to() calls itself recursively. */
980
981 for (address_item * p = tctx->addr; p; p = p->next)
982 if (!write_env_to(p, &plist, &dlist, &first, tctx))
983 goto bad;
984
985 /* Add a final newline and reset the store used for tracking duplicates */
986
987 if (!write_chunk(tctx, US"\n", 1)) goto bad;
988 store_reset(reset_point);
989 }
990
991 /* Add delivery-date: if requested. */
992
993 if (tctx->options & topt_add_delivery_date)
994 {
995 uschar * s = tod_stamp(tod_full);
996
997 if ( !write_chunk(tctx, US"Delivery-date: ", 15)
998 || !write_chunk(tctx, s, Ustrlen(s))
999 || !write_chunk(tctx, US"\n", 1)) goto bad;
1000 }
1001
1002 /* Then the message's headers. Don't write any that are flagged as "old";
1003 that means they were rewritten, or are a record of envelope rewriting, or
1004 were removed (e.g. Bcc). If remove_headers is not null, skip any headers that
1005 match any entries therein. Then check addr->prop.remove_headers too, provided that
1006 addr is not NULL. */
1007
1008 if (!transport_headers_send(tctx, &write_chunk))
1009 {
1010 bad:
1011 f.spool_file_wireformat = save_wireformat;
1012 return FALSE;
1013 }
1014
1015 f.spool_file_wireformat = save_wireformat;
1016 }
1017
1018 /* When doing RFC3030 CHUNKING output, work out how much data would be in a
1019 last-BDAT, consisting of the current write_chunk() output buffer fill
1020 (optimally, all of the headers - but it does not matter if we already had to
1021 flush that buffer with non-last BDAT prependix) plus the amount of body data
1022 (as expanded for CRLF lines). Then create and write BDAT(s), and ensure
1023 that further use of write_chunk() will not prepend BDATs.
1024 The first BDAT written will also first flush any outstanding MAIL and RCPT
1025 commands which were buffered thans to PIPELINING.
1026 Commands go out (using a send()) from a different buffer to data (using a
1027 write()). They might not end up in the same TCP segment, which is
1028 suboptimal. */
1029
1030 if (tctx->options & topt_use_bdat)
1031 {
1032 off_t fsize;
1033 int hsize;
1034
1035 if ((hsize = chunk_ptr - deliver_out_buffer) < 0)
1036 hsize = 0;
1037 if (!(tctx->options & topt_no_body))
1038 {
1039 if ((fsize = lseek(deliver_datafile, 0, SEEK_END)) < 0) return FALSE;
1040 fsize -= SPOOL_DATA_START_OFFSET;
1041 if (size_limit > 0 && fsize > size_limit)
1042 fsize = size_limit;
1043 size = hsize + fsize;
1044 if (tctx->options & topt_use_crlf && !f.spool_file_wireformat)
1045 size += body_linecount; /* account for CRLF-expansion */
1046
1047 /* With topt_use_bdat we never do dot-stuffing; no need to
1048 account for any expansion due to that. */
1049 }
1050
1051 /* If the message is large, emit first a non-LAST chunk with just the
1052 headers, and reap the command responses. This lets us error out early
1053 on RCPT rejects rather than sending megabytes of data. Include headers
1054 on the assumption they are cheap enough and some clever implementations
1055 might errorcheck them too, on-the-fly, and reject that chunk. */
1056
1057 if (size > DELIVER_OUT_BUFFER_SIZE && hsize > 0)
1058 {
1059 DEBUG(D_transport)
1060 debug_printf("sending small initial BDAT; hsize=%d\n", hsize);
1061 if ( tctx->chunk_cb(tctx, hsize, 0) != OK
1062 || !transport_write_block(tctx, deliver_out_buffer, hsize, FALSE)
1063 || tctx->chunk_cb(tctx, 0, tc_reap_prev) != OK
1064 )
1065 return FALSE;
1066 chunk_ptr = deliver_out_buffer;
1067 size -= hsize;
1068 }
1069
1070 /* Emit a LAST datachunk command, and unmark the context for further
1071 BDAT commands. */
1072
1073 if (tctx->chunk_cb(tctx, size, tc_chunk_last) != OK)
1074 return FALSE;
1075 tctx->options &= ~topt_use_bdat;
1076 }
1077
1078 /* If the body is required, ensure that the data for check strings (formerly
1079 the "from hack") is enabled by negating the length if necessary. (It will be
1080 negative in cases where it isn't to apply to the headers). Then ensure the body
1081 is positioned at the start of its file (following the message id), then write
1082 it, applying the size limit if required. */
1083
1084 /* If we have a wireformat -D file (CRNL lines, non-dotstuffed, no ending dot)
1085 and we want to send a body without dotstuffing or ending-dot, in-clear,
1086 then we can just dump it using sendfile.
1087 This should get used for CHUNKING output and also for writing the -K file for
1088 dkim signing, when we had CHUNKING input. */
1089
1090 #ifdef OS_SENDFILE
1091 if ( f.spool_file_wireformat
1092 && !(tctx->options & (topt_no_body | topt_end_dot))
1093 && !nl_check_length
1094 && tls_out.active.sock != tctx->u.fd
1095 )
1096 {
1097 ssize_t copied = 0;
1098 off_t offset = SPOOL_DATA_START_OFFSET;
1099
1100 /* Write out any header data in the buffer */
1101
1102 if ((len = chunk_ptr - deliver_out_buffer) > 0)
1103 {
1104 if (!transport_write_block(tctx, deliver_out_buffer, len, TRUE))
1105 return FALSE;
1106 size -= len;
1107 }
1108
1109 DEBUG(D_transport) debug_printf("using sendfile for body\n");
1110
1111 while(size > 0)
1112 {
1113 if ((copied = os_sendfile(tctx->u.fd, deliver_datafile, &offset, size)) <= 0) break;
1114 size -= copied;
1115 }
1116 return copied >= 0;
1117 }
1118 #else
1119 DEBUG(D_transport) debug_printf("cannot use sendfile for body: no support\n");
1120 #endif
1121
1122 DEBUG(D_transport)
1123 if (!(tctx->options & topt_no_body))
1124 debug_printf("cannot use sendfile for body: %s\n",
1125 !f.spool_file_wireformat ? "spoolfile not wireformat"
1126 : tctx->options & topt_end_dot ? "terminating dot wanted"
1127 : nl_check_length ? "dot- or From-stuffing wanted"
1128 : "TLS output wanted");
1129
1130 if (!(tctx->options & topt_no_body))
1131 {
1132 unsigned long size = size_limit > 0 ? size_limit : ULONG_MAX;
1133
1134 nl_check_length = abs(nl_check_length);
1135 nl_partial_match = 0;
1136 if (lseek(deliver_datafile, SPOOL_DATA_START_OFFSET, SEEK_SET) < 0)
1137 return FALSE;
1138 while ( (len = MIN(DELIVER_IN_BUFFER_SIZE, size)) > 0
1139 && (len = read(deliver_datafile, deliver_in_buffer, len)) > 0)
1140 {
1141 if (!write_chunk(tctx, deliver_in_buffer, len))
1142 return FALSE;
1143 size -= len;
1144 }
1145
1146 /* A read error on the body will have left len == -1 and errno set. */
1147
1148 if (len != 0) return FALSE;
1149 }
1150
1151 /* Finished with the check string, and spool-format consideration */
1152
1153 nl_check_length = nl_escape_length = 0;
1154 f.spool_file_wireformat = FALSE;
1155
1156 /* If requested, add a terminating "." line (SMTP output). */
1157
1158 if (tctx->options & topt_end_dot && !write_chunk(tctx, US".\n", 2))
1159 return FALSE;
1160
1161 /* Write out any remaining data in the buffer before returning. */
1162
1163 return (len = chunk_ptr - deliver_out_buffer) <= 0
1164 || transport_write_block(tctx, deliver_out_buffer, len,
1165 !!(tctx->options & topt_no_flush));
1166 }
1167
1168
1169
1170
1171 /*************************************************
1172 * External interface to write the message *
1173 *************************************************/
1174
1175 /* If there is no filtering required, call the internal function above to do
1176 the real work, passing over all the arguments from this function. Otherwise,
1177 set up a filtering process, fork another process to call the internal function
1178 to write to the filter, and in this process just suck from the filter and write
1179 down the fd in the transport context. At the end, tidy up the pipes and the
1180 processes.
1181
1182 Arguments: as for internal_transport_write_message() above
1183
1184 Returns: TRUE on success; FALSE (with errno) for any failure
1185 transport_count is incremented by the number of bytes written
1186 */
1187
1188 BOOL
transport_write_message(transport_ctx * tctx,int size_limit)1189 transport_write_message(transport_ctx * tctx, int size_limit)
1190 {
1191 BOOL last_filter_was_NL = TRUE;
1192 BOOL save_spool_file_wireformat = f.spool_file_wireformat;
1193 BOOL yield;
1194 int rc, len, fd_read, fd_write, save_errno;
1195 int pfd[2] = {-1, -1};
1196 pid_t filter_pid, write_pid;
1197
1198 f.transport_filter_timed_out = FALSE;
1199
1200 /* If there is no filter command set up, call the internal function that does
1201 the actual work, passing it the incoming fd, and return its result. */
1202
1203 if ( !transport_filter_argv
1204 || !*transport_filter_argv
1205 || !**transport_filter_argv
1206 )
1207 return internal_transport_write_message(tctx, size_limit);
1208
1209 /* Otherwise the message must be written to a filter process and read back
1210 before being written to the incoming fd. First set up the special processing to
1211 be done during the copying. */
1212
1213 nl_partial_match = -1;
1214
1215 if (tctx->check_string && tctx->escape_string)
1216 {
1217 nl_check = tctx->check_string;
1218 nl_check_length = Ustrlen(nl_check);
1219 nl_escape = tctx->escape_string;
1220 nl_escape_length = Ustrlen(nl_escape);
1221 }
1222 else nl_check_length = nl_escape_length = 0;
1223
1224 /* Start up a subprocess to run the command. Ensure that our main fd will
1225 be closed when the subprocess execs, but remove the flag afterwards.
1226 (Otherwise, if this is a TCP/IP socket, it can't get passed on to another
1227 process to deliver another message.) We get back stdin/stdout file descriptors.
1228 If the process creation failed, give an error return. */
1229
1230 fd_read = -1;
1231 fd_write = -1;
1232 save_errno = 0;
1233 yield = FALSE;
1234 write_pid = (pid_t)(-1);
1235
1236 {
1237 int bits = fcntl(tctx->u.fd, F_GETFD);
1238 (void) fcntl(tctx->u.fd, F_SETFD, bits | FD_CLOEXEC);
1239 filter_pid = child_open(USS transport_filter_argv, NULL, 077,
1240 &fd_write, &fd_read, FALSE, US"transport-filter");
1241 (void) fcntl(tctx->u.fd, F_SETFD, bits & ~FD_CLOEXEC);
1242 }
1243 if (filter_pid < 0) goto TIDY_UP; /* errno set */
1244
1245 DEBUG(D_transport)
1246 debug_printf("process %d running as transport filter: fd_write=%d fd_read=%d\n",
1247 (int)filter_pid, fd_write, fd_read);
1248
1249 /* Fork subprocess to write the message to the filter, and return the result
1250 via a(nother) pipe. While writing to the filter, we do not do the CRLF,
1251 smtp dots, or check string processing. */
1252
1253 if (pipe(pfd) != 0) goto TIDY_UP; /* errno set */
1254 if ((write_pid = exim_fork(US"tpt-filter-writer")) == 0)
1255 {
1256 BOOL rc;
1257 (void)close(fd_read);
1258 (void)close(pfd[pipe_read]);
1259 nl_check_length = nl_escape_length = 0;
1260
1261 tctx->u.fd = fd_write;
1262 tctx->check_string = tctx->escape_string = NULL;
1263 tctx->options &= ~(topt_use_crlf | topt_end_dot | topt_use_bdat | topt_no_flush);
1264
1265 rc = internal_transport_write_message(tctx, size_limit);
1266
1267 save_errno = errno;
1268 if ( write(pfd[pipe_write], (void *)&rc, sizeof(BOOL))
1269 != sizeof(BOOL)
1270 || write(pfd[pipe_write], (void *)&save_errno, sizeof(int))
1271 != sizeof(int)
1272 || write(pfd[pipe_write], (void *)&tctx->addr->more_errno, sizeof(int))
1273 != sizeof(int)
1274 || write(pfd[pipe_write], (void *)&tctx->addr->delivery_time, sizeof(struct timeval))
1275 != sizeof(struct timeval)
1276 )
1277 rc = FALSE; /* compiler quietening */
1278 exim_underbar_exit(EXIT_SUCCESS);
1279 }
1280 save_errno = errno;
1281
1282 /* Parent process: close our copy of the writing subprocess' pipes. */
1283
1284 (void)close(pfd[pipe_write]);
1285 (void)close(fd_write);
1286 fd_write = -1;
1287
1288 /* Writing process creation failed */
1289
1290 if (write_pid < 0)
1291 {
1292 errno = save_errno; /* restore */
1293 goto TIDY_UP;
1294 }
1295
1296 /* When testing, let the subprocess get going */
1297
1298 testharness_pause_ms(250);
1299
1300 DEBUG(D_transport)
1301 debug_printf("process %d writing to transport filter\n", (int)write_pid);
1302
1303 /* Copy the message from the filter to the output fd. A read error leaves len
1304 == -1 and errno set. We need to apply a timeout to the read, to cope with
1305 the case when the filter gets stuck, but it can be quite a long one. The
1306 default is 5m, but this is now configurable. */
1307
1308 DEBUG(D_transport) debug_printf("copying from the filter\n");
1309
1310 /* Copy the output of the filter, remembering if the last character was NL. If
1311 no data is returned, that counts as "ended with NL" (default setting of the
1312 variable is TRUE). The output should always be unix-format as we converted
1313 any wireformat source on writing input to the filter. */
1314
1315 f.spool_file_wireformat = FALSE;
1316 chunk_ptr = deliver_out_buffer;
1317
1318 for (;;)
1319 {
1320 sigalrm_seen = FALSE;
1321 ALARM(transport_filter_timeout);
1322 len = read(fd_read, deliver_in_buffer, DELIVER_IN_BUFFER_SIZE);
1323 ALARM_CLR(0);
1324 if (sigalrm_seen)
1325 {
1326 DEBUG(D_transport) debug_printf("timed out reading from filter\n");
1327 errno = ETIMEDOUT;
1328 f.transport_filter_timed_out = TRUE;
1329 goto TIDY_UP;
1330 }
1331
1332 /* If the read was successful, write the block down the original fd,
1333 remembering whether it ends in \n or not. */
1334
1335 if (len > 0)
1336 {
1337 if (!write_chunk(tctx, deliver_in_buffer, len)) goto TIDY_UP;
1338 last_filter_was_NL = (deliver_in_buffer[len-1] == '\n');
1339 }
1340
1341 /* Otherwise, break the loop. If we have hit EOF, set yield = TRUE. */
1342
1343 else
1344 {
1345 if (len == 0) yield = TRUE;
1346 break;
1347 }
1348 }
1349
1350 /* Tidying up code. If yield = FALSE there has been an error and errno is set
1351 to something. Ensure the pipes are all closed and the processes are removed. If
1352 there has been an error, kill the processes before waiting for them, just to be
1353 sure. Also apply a paranoia timeout. */
1354
1355 TIDY_UP:
1356 f.spool_file_wireformat = save_spool_file_wireformat;
1357 save_errno = errno;
1358
1359 (void)close(fd_read);
1360 if (fd_write > 0) (void)close(fd_write);
1361
1362 if (!yield)
1363 {
1364 if (filter_pid > 0) kill(filter_pid, SIGKILL);
1365 if (write_pid > 0) kill(write_pid, SIGKILL);
1366 }
1367
1368 /* Wait for the filter process to complete. */
1369
1370 DEBUG(D_transport) debug_printf("waiting for filter process\n");
1371 if (filter_pid > 0 && (rc = child_close(filter_pid, 30)) != 0 && yield)
1372 {
1373 yield = FALSE;
1374 save_errno = ERRNO_FILTER_FAIL;
1375 tctx->addr->more_errno = rc;
1376 DEBUG(D_transport) debug_printf("filter process returned %d\n", rc);
1377 }
1378
1379 /* Wait for the writing process to complete. If it ends successfully,
1380 read the results from its pipe, provided we haven't already had a filter
1381 process failure. */
1382
1383 DEBUG(D_transport) debug_printf("waiting for writing process\n");
1384 if (write_pid > 0)
1385 {
1386 rc = child_close(write_pid, 30);
1387 if (yield)
1388 if (rc == 0)
1389 {
1390 BOOL ok;
1391 if (read(pfd[pipe_read], (void *)&ok, sizeof(BOOL)) != sizeof(BOOL))
1392 {
1393 DEBUG(D_transport)
1394 debug_printf("pipe read from writing process: %s\n", strerror(errno));
1395 save_errno = ERRNO_FILTER_FAIL;
1396 yield = FALSE;
1397 }
1398 else if (!ok)
1399 {
1400 int dummy = read(pfd[pipe_read], (void *)&save_errno, sizeof(int));
1401 dummy = read(pfd[pipe_read], (void *)&tctx->addr->more_errno, sizeof(int));
1402 dummy = read(pfd[pipe_read], (void *)&tctx->addr->delivery_time, sizeof(struct timeval));
1403 yield = FALSE;
1404 }
1405 }
1406 else
1407 {
1408 yield = FALSE;
1409 save_errno = ERRNO_FILTER_FAIL;
1410 tctx->addr->more_errno = rc;
1411 DEBUG(D_transport) debug_printf("writing process returned %d\n", rc);
1412 }
1413 }
1414 (void)close(pfd[pipe_read]);
1415
1416 /* If there have been no problems we can now add the terminating "." if this is
1417 SMTP output, turning off escaping beforehand. If the last character from the
1418 filter was not NL, insert a NL to make the SMTP protocol work. */
1419
1420 if (yield)
1421 {
1422 nl_check_length = nl_escape_length = 0;
1423 f.spool_file_wireformat = FALSE;
1424 if ( tctx->options & topt_end_dot
1425 && ( last_filter_was_NL
1426 ? !write_chunk(tctx, US".\n", 2)
1427 : !write_chunk(tctx, US"\n.\n", 3)
1428 ) )
1429 yield = FALSE;
1430
1431 /* Write out any remaining data in the buffer. */
1432
1433 else
1434 yield = (len = chunk_ptr - deliver_out_buffer) <= 0
1435 || transport_write_block(tctx, deliver_out_buffer, len, FALSE);
1436 }
1437 else
1438 errno = save_errno; /* From some earlier error */
1439
1440 DEBUG(D_transport)
1441 {
1442 debug_printf("end of filtering transport writing: yield=%d\n", yield);
1443 if (!yield)
1444 debug_printf(" errno=%d more_errno=%d\n", errno, tctx->addr->more_errno);
1445 }
1446
1447 return yield;
1448 }
1449
1450
1451
1452
1453
1454 /*************************************************
1455 * Update waiting database *
1456 *************************************************/
1457
1458 /* This is called when an address is deferred by remote transports that are
1459 capable of sending more than one message over one connection. A database is
1460 maintained for each transport, keeping track of which messages are waiting for
1461 which hosts. The transport can then consult this when eventually a successful
1462 delivery happens, and if it finds that another message is waiting for the same
1463 host, it can fire up a new process to deal with it using the same connection.
1464
1465 The database records are keyed by host name. They can get full if there are
1466 lots of messages waiting, and so there is a continuation mechanism for them.
1467
1468 Each record contains a list of message ids, packed end to end without any
1469 zeros. Each one is MESSAGE_ID_LENGTH bytes long. The count field says how many
1470 in this record, and the sequence field says if there are any other records for
1471 this host. If the sequence field is 0, there are none. If it is 1, then another
1472 record with the name <hostname>:0 exists; if it is 2, then two other records
1473 with sequence numbers 0 and 1 exist, and so on.
1474
1475 Currently, an exhaustive search of all continuation records has to be done to
1476 determine whether to add a message id to a given record. This shouldn't be
1477 too bad except in extreme cases. I can't figure out a *simple* way of doing
1478 better.
1479
1480 Old records should eventually get swept up by the exim_tidydb utility.
1481
1482 Arguments:
1483 hostlist list of hosts that this message could be sent to
1484 tpname name of the transport
1485
1486 Returns: nothing
1487 */
1488
1489 void
transport_update_waiting(host_item * hostlist,uschar * tpname)1490 transport_update_waiting(host_item *hostlist, uschar *tpname)
1491 {
1492 const uschar *prevname = US"";
1493 open_db dbblock;
1494 open_db *dbm_file;
1495
1496 DEBUG(D_transport) debug_printf("updating wait-%s database\n", tpname);
1497
1498 /* Open the database for this transport */
1499
1500 if (!(dbm_file = dbfn_open(string_sprintf("wait-%.200s", tpname),
1501 O_RDWR, &dbblock, TRUE, TRUE)))
1502 return;
1503
1504 /* Scan the list of hosts for which this message is waiting, and ensure
1505 that the message id is in each host record. */
1506
1507 for (host_item * host = hostlist; host; host = host->next)
1508 {
1509 BOOL already = FALSE;
1510 dbdata_wait *host_record;
1511 int host_length;
1512 uschar buffer[256];
1513
1514 /* Skip if this is the same host as we just processed; otherwise remember
1515 the name for next time. */
1516
1517 if (Ustrcmp(prevname, host->name) == 0) continue;
1518 prevname = host->name;
1519
1520 /* Look up the host record; if there isn't one, make an empty one. */
1521
1522 if (!(host_record = dbfn_read(dbm_file, host->name)))
1523 {
1524 host_record = store_get(sizeof(dbdata_wait) + MESSAGE_ID_LENGTH, FALSE);
1525 host_record->count = host_record->sequence = 0;
1526 }
1527
1528 /* Compute the current length */
1529
1530 host_length = host_record->count * MESSAGE_ID_LENGTH;
1531
1532 /* Search the record to see if the current message is already in it. */
1533
1534 for (uschar * s = host_record->text; s < host_record->text + host_length;
1535 s += MESSAGE_ID_LENGTH)
1536 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1537 { already = TRUE; break; }
1538
1539 /* If we haven't found this message in the main record, search any
1540 continuation records that exist. */
1541
1542 for (int i = host_record->sequence - 1; i >= 0 && !already; i--)
1543 {
1544 dbdata_wait *cont;
1545 sprintf(CS buffer, "%.200s:%d", host->name, i);
1546 if ((cont = dbfn_read(dbm_file, buffer)))
1547 {
1548 int clen = cont->count * MESSAGE_ID_LENGTH;
1549 for (uschar * s = cont->text; s < cont->text + clen; s += MESSAGE_ID_LENGTH)
1550 if (Ustrncmp(s, message_id, MESSAGE_ID_LENGTH) == 0)
1551 { already = TRUE; break; }
1552 }
1553 }
1554
1555 /* If this message is already in a record, no need to update. */
1556
1557 if (already)
1558 {
1559 DEBUG(D_transport) debug_printf("already listed for %s\n", host->name);
1560 continue;
1561 }
1562
1563
1564 /* If this record is full, write it out with a new name constructed
1565 from the sequence number, increase the sequence number, and empty
1566 the record. If we're doing a two-phase queue run initial phase, ping the
1567 daemon to consider running a delivery on this host. */
1568
1569 if (host_record->count >= WAIT_NAME_MAX)
1570 {
1571 sprintf(CS buffer, "%.200s:%d", host->name, host_record->sequence);
1572 dbfn_write(dbm_file, buffer, host_record, sizeof(dbdata_wait) + host_length);
1573 #ifndef DISABLE_QUEUE_RAMP
1574 if (f.queue_2stage && queue_fast_ramp && !queue_run_in_order)
1575 queue_notify_daemon(message_id);
1576 #endif
1577 host_record->sequence++;
1578 host_record->count = 0;
1579 host_length = 0;
1580 }
1581
1582 /* If this record is not full, increase the size of the record to
1583 allow for one new message id. */
1584
1585 else
1586 {
1587 dbdata_wait *newr =
1588 store_get(sizeof(dbdata_wait) + host_length + MESSAGE_ID_LENGTH, FALSE);
1589 memcpy(newr, host_record, sizeof(dbdata_wait) + host_length);
1590 host_record = newr;
1591 }
1592
1593 /* Now add the new name on the end */
1594
1595 memcpy(host_record->text + host_length, message_id, MESSAGE_ID_LENGTH);
1596 host_record->count++;
1597 host_length += MESSAGE_ID_LENGTH;
1598
1599 /* Update the database */
1600
1601 dbfn_write(dbm_file, host->name, host_record, sizeof(dbdata_wait) + host_length);
1602 DEBUG(D_transport) debug_printf("added %.*s to queue for %s\n",
1603 MESSAGE_ID_LENGTH, message_id, host->name);
1604 }
1605
1606 /* All now done */
1607
1608 dbfn_close(dbm_file);
1609 }
1610
1611
1612
1613
1614 /*************************************************
1615 * Test for waiting messages *
1616 *************************************************/
1617
1618 /* This function is called by a remote transport which uses the previous
1619 function to remember which messages are waiting for which remote hosts. It's
1620 called after a successful delivery and its job is to check whether there is
1621 another message waiting for the same host. However, it doesn't do this if the
1622 current continue sequence is greater than the maximum supplied as an argument,
1623 or greater than the global connection_max_messages, which, if set, overrides.
1624
1625 Arguments:
1626 transport_name name of the transport
1627 hostname name of the host
1628 local_message_max maximum number of messages down one connection
1629 as set by the caller transport
1630 new_message_id set to the message id of a waiting message
1631 oicf_func function to call to validate if it is ok to send
1632 to this message_id from the current instance.
1633 oicf_data opaque data for oicf_func
1634
1635 Returns: TRUE if new_message_id set; FALSE otherwise
1636 */
1637
1638 typedef struct msgq_s
1639 {
1640 uschar message_id [MESSAGE_ID_LENGTH + 1];
1641 BOOL bKeep;
1642 } msgq_t;
1643
1644 BOOL
transport_check_waiting(const uschar * transport_name,const uschar * hostname,int local_message_max,uschar * new_message_id,oicf oicf_func,void * oicf_data)1645 transport_check_waiting(const uschar *transport_name, const uschar *hostname,
1646 int local_message_max, uschar *new_message_id, oicf oicf_func, void *oicf_data)
1647 {
1648 dbdata_wait *host_record;
1649 int host_length;
1650 open_db dbblock;
1651 open_db *dbm_file;
1652
1653 int i;
1654 struct stat statbuf;
1655
1656 DEBUG(D_transport)
1657 {
1658 debug_printf("transport_check_waiting entered\n");
1659 debug_printf(" sequence=%d local_max=%d global_max=%d\n",
1660 continue_sequence, local_message_max, connection_max_messages);
1661 acl_level++;
1662 }
1663
1664 /* Do nothing if we have hit the maximum number that can be send down one
1665 connection. */
1666
1667 if (connection_max_messages >= 0) local_message_max = connection_max_messages;
1668 if (local_message_max > 0 && continue_sequence >= local_message_max)
1669 {
1670 DEBUG(D_transport)
1671 debug_printf_indent("max messages for one connection reached: returning\n");
1672 goto retfalse;
1673 }
1674
1675 /* Open the waiting information database. */
1676
1677 if (!(dbm_file = dbfn_open(string_sprintf("wait-%.200s", transport_name),
1678 O_RDWR, &dbblock, TRUE, TRUE)))
1679 goto retfalse;
1680
1681 /* See if there is a record for this host; if not, there's nothing to do. */
1682
1683 if (!(host_record = dbfn_read(dbm_file, hostname)))
1684 {
1685 dbfn_close(dbm_file);
1686 DEBUG(D_transport) debug_printf_indent("no messages waiting for %s\n", hostname);
1687 goto retfalse;
1688 }
1689
1690 /* If the data in the record looks corrupt, just log something and
1691 don't try to use it. */
1692
1693 if (host_record->count > WAIT_NAME_MAX)
1694 {
1695 dbfn_close(dbm_file);
1696 log_write(0, LOG_MAIN|LOG_PANIC, "smtp-wait database entry for %s has bad "
1697 "count=%d (max=%d)", hostname, host_record->count, WAIT_NAME_MAX);
1698 goto retfalse;
1699 }
1700
1701 /* Scan the message ids in the record from the end towards the beginning,
1702 until one is found for which a spool file actually exists. If the record gets
1703 emptied, delete it and continue with any continuation records that may exist.
1704 */
1705
1706 /* For Bug 1141, I refactored this major portion of the routine, it is risky
1707 but the 1 off will remain without it. This code now allows me to SKIP over
1708 a message I do not want to send out on this run. */
1709
1710 host_length = host_record->count * MESSAGE_ID_LENGTH;
1711
1712 while (1)
1713 {
1714 msgq_t *msgq;
1715 int msgq_count = 0;
1716 int msgq_actual = 0;
1717 BOOL bFound = FALSE;
1718 BOOL bContinuation = FALSE;
1719
1720 /* create an array to read entire message queue into memory for processing */
1721
1722 msgq = store_get(sizeof(msgq_t) * host_record->count, FALSE);
1723 msgq_count = host_record->count;
1724 msgq_actual = msgq_count;
1725
1726 for (i = 0; i < host_record->count; ++i)
1727 {
1728 msgq[i].bKeep = TRUE;
1729
1730 Ustrncpy_nt(msgq[i].message_id, host_record->text + (i * MESSAGE_ID_LENGTH),
1731 MESSAGE_ID_LENGTH);
1732 msgq[i].message_id[MESSAGE_ID_LENGTH] = 0;
1733 }
1734
1735 /* first thing remove current message id if it exists */
1736 /*XXX but what if it has un-sent addrs? */
1737
1738 for (i = 0; i < msgq_count; ++i)
1739 if (Ustrcmp(msgq[i].message_id, message_id) == 0)
1740 {
1741 msgq[i].bKeep = FALSE;
1742 break;
1743 }
1744
1745 /* now find the next acceptable message_id */
1746
1747 for (i = msgq_count - 1; i >= 0; --i) if (msgq[i].bKeep)
1748 {
1749 uschar subdir[2];
1750 uschar * mid = msgq[i].message_id;
1751
1752 set_subdir_str(subdir, mid, 0);
1753 if (Ustat(spool_fname(US"input", subdir, mid, US"-D"), &statbuf) != 0)
1754 msgq[i].bKeep = FALSE;
1755 else if (!oicf_func || oicf_func(mid, oicf_data))
1756 {
1757 Ustrcpy_nt(new_message_id, mid);
1758 msgq[i].bKeep = FALSE;
1759 bFound = TRUE;
1760 break;
1761 }
1762 }
1763
1764 /* re-count */
1765 for (msgq_actual = 0, i = 0; i < msgq_count; ++i)
1766 if (msgq[i].bKeep)
1767 msgq_actual++;
1768
1769 /* reassemble the host record, based on removed message ids, from in
1770 memory queue */
1771
1772 if (msgq_actual <= 0)
1773 {
1774 host_length = 0;
1775 host_record->count = 0;
1776 }
1777 else
1778 {
1779 host_length = msgq_actual * MESSAGE_ID_LENGTH;
1780 host_record->count = msgq_actual;
1781
1782 if (msgq_actual < msgq_count)
1783 {
1784 int new_count;
1785 for (new_count = 0, i = 0; i < msgq_count; ++i)
1786 if (msgq[i].bKeep)
1787 Ustrncpy(&host_record->text[new_count++ * MESSAGE_ID_LENGTH],
1788 msgq[i].message_id, MESSAGE_ID_LENGTH);
1789
1790 host_record->text[new_count * MESSAGE_ID_LENGTH] = 0;
1791 }
1792 }
1793
1794 /* Check for a continuation record. */
1795
1796 while (host_length <= 0)
1797 {
1798 dbdata_wait * newr = NULL;
1799 uschar buffer[256];
1800
1801 /* Search for a continuation */
1802
1803 for (int i = host_record->sequence - 1; i >= 0 && !newr; i--)
1804 {
1805 sprintf(CS buffer, "%.200s:%d", hostname, i);
1806 newr = dbfn_read(dbm_file, buffer);
1807 }
1808
1809 /* If no continuation, delete the current and break the loop */
1810
1811 if (!newr)
1812 {
1813 dbfn_delete(dbm_file, hostname);
1814 break;
1815 }
1816
1817 /* Else replace the current with the continuation */
1818
1819 dbfn_delete(dbm_file, buffer);
1820 host_record = newr;
1821 host_length = host_record->count * MESSAGE_ID_LENGTH;
1822
1823 bContinuation = TRUE;
1824 }
1825
1826 if (bFound) /* Usual exit from main loop */
1827 break;
1828
1829 /* If host_length <= 0 we have emptied a record and not found a good message,
1830 and there are no continuation records. Otherwise there is a continuation
1831 record to process. */
1832
1833 if (host_length <= 0)
1834 {
1835 dbfn_close(dbm_file);
1836 DEBUG(D_transport) debug_printf_indent("waiting messages already delivered\n");
1837 goto retfalse;
1838 }
1839
1840 /* we were not able to find an acceptable message, nor was there a
1841 * continuation record. So bug out, outer logic will clean this up.
1842 */
1843
1844 if (!bContinuation)
1845 {
1846 Ustrcpy(new_message_id, message_id);
1847 dbfn_close(dbm_file);
1848 goto retfalse;
1849 }
1850 } /* we need to process a continuation record */
1851
1852 /* Control gets here when an existing message has been encountered; its
1853 id is in new_message_id, and host_length is the revised length of the
1854 host record. If it is zero, the record has been removed. Update the
1855 record if required, close the database, and return TRUE. */
1856
1857 if (host_length > 0)
1858 {
1859 host_record->count = host_length/MESSAGE_ID_LENGTH;
1860 dbfn_write(dbm_file, hostname, host_record, (int)sizeof(dbdata_wait) + host_length);
1861 }
1862
1863 dbfn_close(dbm_file);
1864 DEBUG(D_transport) {acl_level--; debug_printf("transport_check_waiting: TRUE\n"); }
1865 return TRUE;
1866
1867 retfalse:
1868 DEBUG(D_transport) {acl_level--; debug_printf("transport_check_waiting: FALSE\n"); }
1869 return FALSE;
1870 }
1871
1872 /*************************************************
1873 * Deliver waiting message down same socket *
1874 *************************************************/
1875
1876 /* Just the regain-root-privilege exec portion */
1877 void
transport_do_pass_socket(const uschar * transport_name,const uschar * hostname,const uschar * hostaddress,uschar * id,int socket_fd)1878 transport_do_pass_socket(const uschar *transport_name, const uschar *hostname,
1879 const uschar *hostaddress, uschar *id, int socket_fd)
1880 {
1881 int i = 13;
1882 const uschar **argv;
1883
1884 #ifndef DISABLE_TLS
1885 if (smtp_peer_options & OPTION_TLS) i += 6;
1886 #endif
1887 #ifdef EXPERIMENTAL_ESMTP_LIMITS
1888 if (continue_limit_mail || continue_limit_rcpt || continue_limit_rcptdom)
1889 i += 4;
1890 #endif
1891 if (queue_run_pid != (pid_t)0) i += 3;
1892 #ifdef SUPPORT_SOCKS
1893 if (proxy_session) i += 5;
1894 #endif
1895
1896 /* Set up the calling arguments; use the standard function for the basics,
1897 but we have a number of extras that may be added. */
1898
1899 argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, &i, FALSE, 0);
1900
1901 if (f.smtp_authenticated) argv[i++] = US"-MCA";
1902 if (smtp_peer_options & OPTION_CHUNKING) argv[i++] = US"-MCK";
1903 if (smtp_peer_options & OPTION_DSN) argv[i++] = US"-MCD";
1904 if (smtp_peer_options & OPTION_PIPE) argv[i++] = US"-MCP";
1905 if (smtp_peer_options & OPTION_SIZE) argv[i++] = US"-MCS";
1906 #ifndef DISABLE_TLS
1907 if (smtp_peer_options & OPTION_TLS)
1908 if (tls_out.active.sock >= 0 || continue_proxy_cipher)
1909 {
1910 argv[i++] = US"-MCt";
1911 argv[i++] = sending_ip_address;
1912 argv[i++] = string_sprintf("%d", sending_port);
1913 argv[i++] = tls_out.active.sock >= 0 ? tls_out.cipher : continue_proxy_cipher;
1914
1915 if (tls_out.sni)
1916 {
1917 argv[i++] =
1918 #ifdef SUPPORT_DANE
1919 tls_out.dane_verified ? US"-MCr" :
1920 #endif
1921 US"-MCs";
1922 argv[i++] = tls_out.sni;
1923 }
1924 }
1925 else
1926 argv[i++] = US"-MCT";
1927 #endif
1928
1929 #ifdef EXPERIMENTAL_ESMTP_LIMITS
1930 if (continue_limit_rcpt || continue_limit_rcptdom)
1931 {
1932 argv[i++] = US"-MCL";
1933 argv[i++] = string_sprintf("%u", continue_limit_mail);
1934 argv[i++] = string_sprintf("%u", continue_limit_rcpt);
1935 argv[i++] = string_sprintf("%u", continue_limit_rcptdom);
1936 }
1937 #endif
1938
1939 if (queue_run_pid != (pid_t)0)
1940 {
1941 argv[i++] = US"-MCQ";
1942 argv[i++] = string_sprintf("%d", queue_run_pid);
1943 argv[i++] = string_sprintf("%d", queue_run_pipe);
1944 }
1945
1946 #ifdef SUPPORT_SOCKS
1947 if (proxy_session)
1948 {
1949 argv[i++] = US"-MCp";
1950 argv[i++] = proxy_local_address;
1951 argv[i++] = string_sprintf("%d", proxy_local_port);
1952 argv[i++] = proxy_external_address;
1953 argv[i++] = string_sprintf("%d", proxy_external_port);
1954 }
1955 #endif
1956
1957 argv[i++] = US"-MC";
1958 argv[i++] = US transport_name;
1959 argv[i++] = US hostname;
1960 argv[i++] = US hostaddress;
1961 argv[i++] = string_sprintf("%d", continue_sequence + 1);
1962 argv[i++] = id;
1963 argv[i++] = NULL;
1964
1965 /* Arrange for the channel to be on stdin. */
1966
1967 if (socket_fd != 0)
1968 {
1969 (void)dup2(socket_fd, 0);
1970 (void)close(socket_fd);
1971 }
1972
1973 DEBUG(D_exec) debug_print_argv(argv);
1974 exim_nullstd(); /* Ensure std{out,err} exist */
1975 execv(CS argv[0], (char *const *)argv);
1976
1977 DEBUG(D_any) debug_printf("execv failed: %s\n", strerror(errno));
1978 _exit(errno); /* Note: must be _exit(), NOT exit() */
1979 }
1980
1981
1982
1983 /* Fork a new exim process to deliver the message, and do a re-exec, both to
1984 get a clean delivery process, and to regain root privilege in cases where it
1985 has been given away.
1986
1987 Arguments:
1988 transport_name to pass to the new process
1989 hostname ditto
1990 hostaddress ditto
1991 id the new message to process
1992 socket_fd the connected socket
1993
1994 Returns: FALSE if fork fails; TRUE otherwise
1995 */
1996
1997 BOOL
transport_pass_socket(const uschar * transport_name,const uschar * hostname,const uschar * hostaddress,uschar * id,int socket_fd,unsigned peer_limit_mail,unsigned peer_limit_rcpt,unsigned peer_limit_rcptdom)1998 transport_pass_socket(const uschar *transport_name, const uschar *hostname,
1999 const uschar *hostaddress, uschar *id, int socket_fd
2000 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2001 , unsigned peer_limit_mail, unsigned peer_limit_rcpt, unsigned peer_limit_rcptdom
2002 #endif
2003 )
2004 {
2005 pid_t pid;
2006 int status;
2007
2008 DEBUG(D_transport) debug_printf("transport_pass_socket entered\n");
2009
2010 #ifdef EXPERIMENTAL_ESMTP_LIMITS
2011 continue_limit_mail = peer_limit_mail;
2012 continue_limit_rcpt = peer_limit_rcpt;
2013 continue_limit_rcptdom = peer_limit_rcptdom;
2014 #endif
2015
2016 if ((pid = exim_fork(US"continued-transport-interproc")) == 0)
2017 {
2018 /* Disconnect entirely from the parent process. If we are running in the
2019 test harness, wait for a bit to allow the previous process time to finish,
2020 write the log, etc., so that the output is always in the same order for
2021 automatic comparison. */
2022
2023 if ((pid = exim_fork(US"continued-transport")) != 0)
2024 _exit(EXIT_SUCCESS);
2025 testharness_pause_ms(1000);
2026
2027 transport_do_pass_socket(transport_name, hostname, hostaddress,
2028 id, socket_fd);
2029 }
2030
2031 /* If the process creation succeeded, wait for the first-level child, which
2032 immediately exits, leaving the second level process entirely disconnected from
2033 this one. */
2034
2035 if (pid > 0)
2036 {
2037 int rc;
2038 while ((rc = wait(&status)) != pid && (rc >= 0 || errno != ECHILD));
2039 return TRUE;
2040 }
2041 else
2042 {
2043 DEBUG(D_transport) debug_printf("transport_pass_socket failed to fork: %s\n",
2044 strerror(errno));
2045 return FALSE;
2046 }
2047 }
2048
2049
2050
2051 /*************************************************
2052 * Set up direct (non-shell) command *
2053 *************************************************/
2054
2055 /* This function is called when a command line is to be parsed and executed
2056 directly, without the use of /bin/sh. It is called by the pipe transport,
2057 the queryprogram router, and also from the main delivery code when setting up a
2058 transport filter process. The code for ETRN also makes use of this; in that
2059 case, no addresses are passed.
2060
2061 Arguments:
2062 argvptr pointer to anchor for argv vector
2063 cmd points to the command string (modified IN PLACE)
2064 expand_arguments true if expansion is to occur
2065 expand_failed error value to set if expansion fails; not relevant if
2066 addr == NULL
2067 addr chain of addresses, or NULL
2068 etext text for use in error messages
2069 errptr where to put error message if addr is NULL;
2070 otherwise it is put in the first address
2071
2072 Returns: TRUE if all went well; otherwise an error will be
2073 set in the first address and FALSE returned
2074 */
2075
2076 BOOL
transport_set_up_command(const uschar *** argvptr,uschar * cmd,BOOL expand_arguments,int expand_failed,address_item * addr,uschar * etext,uschar ** errptr)2077 transport_set_up_command(const uschar ***argvptr, uschar *cmd,
2078 BOOL expand_arguments, int expand_failed, address_item *addr,
2079 uschar *etext, uschar **errptr)
2080 {
2081 const uschar **argv;
2082 uschar *s, *ss;
2083 int address_count = 0;
2084 int argcount = 0;
2085 int max_args;
2086
2087 /* Get store in which to build an argument list. Count the number of addresses
2088 supplied, and allow for that many arguments, plus an additional 60, which
2089 should be enough for anybody. Multiple addresses happen only when the local
2090 delivery batch option is set. */
2091
2092 for (address_item * ad = addr; ad; ad = ad->next) address_count++;
2093 max_args = address_count + 60;
2094 *argvptr = argv = store_get((max_args+1)*sizeof(uschar *), FALSE);
2095
2096 /* Split the command up into arguments terminated by white space. Lose
2097 trailing space at the start and end. Double-quoted arguments can contain \\ and
2098 \" escapes and so can be handled by the standard function; single-quoted
2099 arguments are verbatim. Copy each argument into a new string. */
2100
2101 s = cmd;
2102 while (isspace(*s)) s++;
2103
2104 for (; *s != 0 && argcount < max_args; argcount++)
2105 {
2106 if (*s == '\'')
2107 {
2108 ss = s + 1;
2109 while (*ss != 0 && *ss != '\'') ss++;
2110 argv[argcount] = ss = store_get(ss - s++, is_tainted(cmd));
2111 while (*s != 0 && *s != '\'') *ss++ = *s++;
2112 if (*s != 0) s++;
2113 *ss++ = 0;
2114 }
2115 else
2116 argv[argcount] = string_dequote(CUSS &s);
2117 while (isspace(*s)) s++;
2118 }
2119
2120 argv[argcount] = US 0;
2121
2122 /* If *s != 0 we have run out of argument slots. */
2123
2124 if (*s != 0)
2125 {
2126 uschar *msg = string_sprintf("Too many arguments in command \"%s\" in "
2127 "%s", cmd, etext);
2128 if (addr != NULL)
2129 {
2130 addr->transport_return = FAIL;
2131 addr->message = msg;
2132 }
2133 else *errptr = msg;
2134 return FALSE;
2135 }
2136
2137 /* Expand each individual argument if required. Expansion happens for pipes set
2138 up in filter files and with directly-supplied commands. It does not happen if
2139 the pipe comes from a traditional .forward file. A failing expansion is a big
2140 disaster if the command came from Exim's configuration; if it came from a user
2141 it is just a normal failure. The expand_failed value is used as the error value
2142 to cater for these two cases.
2143
2144 An argument consisting just of the text "$pipe_addresses" is treated specially.
2145 It is not passed to the general expansion function. Instead, it is replaced by
2146 a number of arguments, one for each address. This avoids problems with shell
2147 metacharacters and spaces in addresses.
2148
2149 If the parent of the top address has an original part of "system-filter", this
2150 pipe was set up by the system filter, and we can permit the expansion of
2151 $recipients. */
2152
2153 DEBUG(D_transport)
2154 {
2155 debug_printf("direct command:\n");
2156 for (int i = 0; argv[i]; i++)
2157 debug_printf(" argv[%d] = '%s'\n", i, string_printing(argv[i]));
2158 }
2159
2160 if (expand_arguments)
2161 {
2162 BOOL allow_dollar_recipients = addr != NULL &&
2163 addr->parent != NULL &&
2164 Ustrcmp(addr->parent->address, "system-filter") == 0;
2165
2166 for (int i = 0; argv[i] != US 0; i++)
2167 {
2168
2169 /* Handle special fudge for passing an address list */
2170
2171 if (addr != NULL &&
2172 (Ustrcmp(argv[i], "$pipe_addresses") == 0 ||
2173 Ustrcmp(argv[i], "${pipe_addresses}") == 0))
2174 {
2175 int additional;
2176
2177 if (argcount + address_count - 1 > max_args)
2178 {
2179 addr->transport_return = FAIL;
2180 addr->message = string_sprintf("Too many arguments to command \"%s\" "
2181 "in %s", cmd, etext);
2182 return FALSE;
2183 }
2184
2185 additional = address_count - 1;
2186 if (additional > 0)
2187 memmove(argv + i + 1 + additional, argv + i + 1,
2188 (argcount - i)*sizeof(uschar *));
2189
2190 for (address_item * ad = addr; ad; ad = ad->next)
2191 {
2192 argv[i++] = ad->address;
2193 argcount++;
2194 }
2195
2196 /* Subtract one since we replace $pipe_addresses */
2197 argcount--;
2198 i--;
2199 }
2200
2201 /* Handle special case of $address_pipe when af_force_command is set */
2202
2203 else if (addr != NULL && testflag(addr,af_force_command) &&
2204 (Ustrcmp(argv[i], "$address_pipe") == 0 ||
2205 Ustrcmp(argv[i], "${address_pipe}") == 0))
2206 {
2207 int address_pipe_argcount = 0;
2208 int address_pipe_max_args;
2209 uschar **address_pipe_argv;
2210 BOOL tainted;
2211
2212 /* We can never have more then the argv we will be loading into */
2213 address_pipe_max_args = max_args - argcount + 1;
2214
2215 DEBUG(D_transport)
2216 debug_printf("address_pipe_max_args=%d\n", address_pipe_max_args);
2217
2218 /* We allocate an additional for (uschar *)0 */
2219 address_pipe_argv = store_get((address_pipe_max_args+1)*sizeof(uschar *), FALSE);
2220
2221 /* +1 because addr->local_part[0] == '|' since af_force_command is set */
2222 s = expand_string(addr->local_part + 1);
2223 tainted = is_tainted(s);
2224
2225 if (s == NULL || *s == '\0')
2226 {
2227 addr->transport_return = FAIL;
2228 addr->message = string_sprintf("Expansion of \"%s\" "
2229 "from command \"%s\" in %s failed: %s",
2230 (addr->local_part + 1), cmd, etext, expand_string_message);
2231 return FALSE;
2232 }
2233
2234 while (isspace(*s)) s++; /* strip leading space */
2235
2236 while (*s != 0 && address_pipe_argcount < address_pipe_max_args)
2237 {
2238 if (*s == '\'')
2239 {
2240 ss = s + 1;
2241 while (*ss != 0 && *ss != '\'') ss++;
2242 address_pipe_argv[address_pipe_argcount++] = ss = store_get(ss - s++, tainted);
2243 while (*s != 0 && *s != '\'') *ss++ = *s++;
2244 if (*s != 0) s++;
2245 *ss++ = 0;
2246 }
2247 else address_pipe_argv[address_pipe_argcount++] =
2248 string_copy(string_dequote(CUSS &s));
2249 while (isspace(*s)) s++; /* strip space after arg */
2250 }
2251
2252 address_pipe_argv[address_pipe_argcount] = US 0;
2253
2254 /* If *s != 0 we have run out of argument slots. */
2255 if (*s != 0)
2256 {
2257 uschar *msg = string_sprintf("Too many arguments in $address_pipe "
2258 "\"%s\" in %s", addr->local_part + 1, etext);
2259 if (addr != NULL)
2260 {
2261 addr->transport_return = FAIL;
2262 addr->message = msg;
2263 }
2264 else *errptr = msg;
2265 return FALSE;
2266 }
2267
2268 /* address_pipe_argcount - 1
2269 * because we are replacing $address_pipe in the argument list
2270 * with the first thing it expands to */
2271 if (argcount + address_pipe_argcount - 1 > max_args)
2272 {
2273 addr->transport_return = FAIL;
2274 addr->message = string_sprintf("Too many arguments to command "
2275 "\"%s\" after expanding $address_pipe in %s", cmd, etext);
2276 return FALSE;
2277 }
2278
2279 /* If we are not just able to replace the slot that contained
2280 $address_pipe (address_pipe_argcount == 1)
2281 We have to move the existing argv by address_pipe_argcount - 1
2282 Visually if address_pipe_argcount == 2:
2283 [argv 0][argv 1][argv 2($address_pipe)][argv 3][0]
2284 [argv 0][argv 1][ap_arg0][ap_arg1][old argv 3][0] */
2285
2286 if (address_pipe_argcount > 1)
2287 memmove(
2288 /* current position + additional args */
2289 argv + i + address_pipe_argcount,
2290 /* current position + 1 (for the (uschar *)0 at the end) */
2291 argv + i + 1,
2292 /* -1 for the (uschar *)0 at the end)*/
2293 (argcount - i)*sizeof(uschar *)
2294 );
2295
2296 /* Now we fill in the slots we just moved argv out of
2297 [argv 0][argv 1][argv 2=pipeargv[0]][argv 3=pipeargv[1]][old argv 3][0] */
2298
2299 for (int address_pipe_i = 0;
2300 address_pipe_argv[address_pipe_i] != US 0;
2301 address_pipe_i++, argcount++)
2302 argv[i++] = address_pipe_argv[address_pipe_i];
2303
2304 /* Subtract one since we replace $address_pipe */
2305 argcount--;
2306 i--;
2307 }
2308
2309 /* Handle normal expansion string */
2310
2311 else
2312 {
2313 const uschar *expanded_arg;
2314 f.enable_dollar_recipients = allow_dollar_recipients;
2315 expanded_arg = expand_cstring(argv[i]);
2316 f.enable_dollar_recipients = FALSE;
2317
2318 if (!expanded_arg)
2319 {
2320 uschar *msg = string_sprintf("Expansion of \"%s\" "
2321 "from command \"%s\" in %s failed: %s",
2322 argv[i], cmd, etext, expand_string_message);
2323 if (addr)
2324 {
2325 addr->transport_return = expand_failed;
2326 addr->message = msg;
2327 }
2328 else *errptr = msg;
2329 return FALSE;
2330 }
2331 argv[i] = expanded_arg;
2332 }
2333 }
2334
2335 DEBUG(D_transport)
2336 {
2337 debug_printf("direct command after expansion:\n");
2338 for (int i = 0; argv[i] != US 0; i++)
2339 debug_printf(" argv[%d] = %s\n", i, string_printing(argv[i]));
2340 }
2341 }
2342
2343 return TRUE;
2344 }
2345
2346 #endif /*!MACRO_PREDEF*/
2347 /* vi: aw ai sw=2
2348 */
2349 /* End of transport.c */
2350