2 * sink.c -- forwarding/delivery support for fetchmail
4 * The interface of this module (open_sink(), stuff_line(), close_sink(),
5 * release_sink()) seals off the delivery logic from the protocol machine,
6 * so the latter won't have to care whether it's shipping to an [SL]MTP
7 * listener daemon or an MDA pipe.
9 * Copyright 1998 by Eric S. Raymond
10 * For license terms, see the file COPYING in this directory.
21 #endif /* HAVE_MEMORY_H */
22 #if defined(STDC_HEADERS)
25 #if defined(HAVE_UNISTD_H)
28 #if defined(HAVE_STDARG_H)
36 #include "fetchmail.h"
41 /* BSD portability hack...I know, this is an ugly place to put it */
42 #if !defined(SIGCHLD) && defined(SIGCLD)
43 #define SIGCHLD SIGCLD
46 /* makes the open_sink()/close_sink() pair non-reentrant */
47 static int lmtp_responses;
49 void smtp_close(struct query *ctl, int sayquit)
50 /* close the socket to SMTP server */
52 if (ctl->smtp_socket != -1)
55 SMTP_quit(ctl->smtp_socket);
56 SockClose(ctl->smtp_socket);
57 ctl->smtp_socket = -1;
62 int smtp_open(struct query *ctl)
63 /* try to open a socket to the appropriate SMTP server for this query */
65 char *parsed_host = NULL;
67 /* maybe it's time to close the socket in order to force delivery */
68 if (NUM_NONZERO(ctl->batchlimit)) {
69 if (batchcount == ctl->batchlimit)
74 /* if no socket to any SMTP host is already set up, try to open one */
75 if (ctl->smtp_socket == -1)
78 * RFC 1123 requires that the domain name in HELO address is a
79 * "valid principal domain name" for the client host. If we're
80 * running in invisible mode, violate this with malice
81 * aforethought in order to make the Received headers and
84 * In fact this code relies on the RFC1123 requirement that the
85 * SMTP listener must accept messages even if verification of the
86 * HELO name fails (RFC1123 section 5.2.5, paragraph 2).
88 * How we compute the true mailhost name to pass to the
89 * listener doesn't affect behavior on RFC1123-violating
90 * listeners that check for name match; we're going to lose
91 * on those anyway because we can never give them a name
92 * that matches the local machine fetchmail is running on.
93 * What it will affect is the listener's logging.
96 const char *id_me = run.invisible ? ctl->server.truename : fetchmailhost;
102 * Run down the SMTP hunt list looking for a server that's up.
103 * Use both explicit hunt entries (value TRUE) and implicit
104 * (default) ones (value FALSE).
107 phase = LISTENER_WAIT;
109 set_timeout(ctl->server.timeout);
110 for (idp = ctl->smtphunt; idp; idp = idp->next)
114 char *portnum = SMTP_PORT;
116 int portnum = SMTP_PORT;
117 #endif /* INET6_ENABLE */
119 xalloca(parsed_host, char *, strlen(idp->id) + 1);
121 ctl->smtphost = idp->id; /* remember last host tried. */
122 if(ctl->smtphost[0]=='/')
123 ctl->listener = LMTP_MODE;
125 strcpy(parsed_host, idp->id);
126 if ((cp = strrchr(parsed_host, '/')))
133 #endif /* INET6_ENABLE */
136 if (ctl->smtphost[0]=='/'){
137 if ((ctl->smtp_socket = UnixOpen(ctl->smtphost))==-1)
140 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,NULL,
141 ctl->server.plugout)) == -1)
144 /* return immediately for ODMR */
145 if (ctl->server.protocol == P_ODMR)
149 return(ctl->smtp_socket); /* success */
152 /* are we doing SMTP or LMTP? */
153 SMTP_setmode(ctl->listener);
155 /* first, probe for ESMTP */
156 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
157 SMTP_ehlo(ctl->smtp_socket, id_me,
158 &ctl->server.esmtp_options) == SM_OK)
162 * RFC 1869 warns that some listeners hang up on a failed EHLO,
163 * so it's safest not to assume the socket will still be good.
167 /* if opening for ESMTP failed, try SMTP */
168 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,NULL,
169 ctl->server.plugout)) == -1)
172 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
173 SMTP_helo(ctl->smtp_socket, id_me) == SM_OK)
183 * RFC 1123 requires that the domain name part of the
184 * RCPT TO address be "canonicalized", that is a FQDN
185 * or MX but not a CNAME. Some listeners (like exim)
186 * enforce this. Now that we have the actual hostname,
187 * compute what we should canonicalize with.
189 * make sure we do not forget to drop the /port if
192 if (ctl->listener == LMTP_MODE && !ctl->smtpaddress)
194 if (parsed_host && parsed_host[0] != 0)
195 ctl->destaddr = xstrdup(parsed_host);
197 ctl->destaddr = (ctl->smtphost && ctl->smtphost[0] != '/') ? ctl->smtphost : "localhost";
200 ctl->destaddr = ctl->smtpaddress ? ctl->smtpaddress : ( ctl->smtphost && ctl->smtphost[0] != '/' ? ctl->smtphost : "localhost");
202 if (outlevel >= O_DEBUG && ctl->smtp_socket != -1)
203 report(stdout, GT_("forwarding to %s\n"), ctl->smtphost);
205 return(ctl->smtp_socket);
208 static void sanitize(char *s)
209 /* replace unsafe shellchars by an _ */
211 const static char *ok_chars = " 1234567890!@%-_=+:,./abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
214 for (cp = s; *(cp += strspn(cp, ok_chars)); /* NO INCREMENT */)
218 static int send_bouncemail(struct query *ctl, struct msgblk *msg,
219 int userclass, char *message,
220 int nerrors, char *errors[])
221 /* bounce back an error report a la RFC 1892 */
223 char daemon_name[18 + HOSTLEN] = "FETCHMAIL-DAEMON@";
224 char boundary[BUFSIZ], *bounce_to;
227 /* don't bounce in reply to undeliverable bounces */
228 if (!msg->return_path[0] || strcmp(msg->return_path, "<>") == 0)
231 bounce_to = (run.bouncemail ? msg->return_path : run.postmaster);
233 SMTP_setmode(SMTP_MODE);
235 /* can't just use fetchmailhost here, it might be localhost */
236 strcat(daemon_name, host_fqdn());
238 /* we need only SMTP for this purpose */
239 if ((sock = SockOpen("localhost", SMTP_PORT, NULL, NULL)) == -1
240 || SMTP_ok(sock) != SM_OK
241 || SMTP_helo(sock, fetchmailhost) != SM_OK
242 || SMTP_from(sock, daemon_name, (char *)NULL) != SM_OK
243 || SMTP_rcpt(sock, bounce_to) != SM_OK
244 || SMTP_data(sock) != SM_OK)
247 /* our first duty is to keep the sacred foo counters turning... */
249 snprintf(boundary, sizeof(boundary),
252 #endif /* HAVE_SNPRINTF */
253 "foo-mani-padme-hum-%d-%d-%ld",
254 (int)getpid(), (int)getppid(), time((time_t *)NULL));
256 if (outlevel >= O_VERBOSE)
257 report(stdout, GT_("SMTP: (bounce-message body)\n"));
259 /* this will usually go to sylog... */
260 report(stderr, GT_("mail from %s bounced to %s\n"),
261 daemon_name, bounce_to);
263 /* bouncemail headers */
264 SockPrintf(sock, "Return-Path: <>\r\n");
265 SockPrintf(sock, "From: %s\r\n", daemon_name);
266 SockPrintf(sock, "To: %s\r\n", bounce_to);
267 SockPrintf(sock, "MIME-Version: 1.0\r\n");
268 SockPrintf(sock, "Content-Type: multipart/report; report-type=delivery-status;\r\n\tboundary=\"%s\"\r\n", boundary);
269 SockPrintf(sock, "\r\n");
271 /* RFC1892 part 1 -- human-readable message */
272 SockPrintf(sock, "--%s\r\n", boundary);
273 SockPrintf(sock,"Content-Type: text/plain\r\n");
274 SockPrintf(sock, "\r\n");
275 SockWrite(sock, message, strlen(message));
276 SockPrintf(sock, "\r\n");
277 SockPrintf(sock, "\r\n");
284 /* RFC1892 part 2 -- machine-readable responses */
285 SockPrintf(sock, "--%s\r\n", boundary);
286 SockPrintf(sock,"Content-Type: message/delivery-status\r\n");
287 SockPrintf(sock, "\r\n");
288 SockPrintf(sock, "Reporting-MTA: dns; %s\r\n", fetchmailhost);
291 for (idp = msg->recipients; idp; idp = idp->next)
292 if (idp->val.status.mark == userclass)
295 /* Minimum RFC1894 compliance + Diagnostic-Code field */
296 SockPrintf(sock, "\r\n");
297 SockPrintf(sock, "Final-Recipient: rfc822; %s@%s\r\n",
298 idp->id, fetchmailhost);
299 SockPrintf(sock, "Last-Attempt-Date: %s\r\n", rfc822timestamp());
300 SockPrintf(sock, "Action: failed\r\n");
303 /* one error applies to all users */
305 else if (nerrors > nusers)
307 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
311 /* errors correspond 1-1 to selected users */
312 error = errors[nusers++];
314 if (strlen(error) > 9 && isdigit(error[4])
315 && error[5] == '.' && isdigit(error[6])
316 && error[7] == '.' && isdigit(error[8]))
317 /* Enhanced status code available, use it */
318 SockPrintf(sock, "Status: %5.5s\r\n", &(error[4]));
320 /* Enhanced status code not available, fake one */
321 SockPrintf(sock, "Status: %c.0.0\r\n", error[0]);
322 SockPrintf(sock, "Diagnostic-Code: %s\r\n", error);
324 SockPrintf(sock, "\r\n");
327 /* RFC1892 part 3 -- headers of undelivered message */
328 SockPrintf(sock, "--%s\r\n", boundary);
329 SockPrintf(sock, "Content-Type: text/rfc822-headers\r\n");
330 SockPrintf(sock, "\r\n");
331 SockWrite(sock, msg->headers, strlen(msg->headers));
332 SockPrintf(sock, "\r\n");
333 SockPrintf(sock, "--%s--\r\n", boundary);
335 if (SMTP_eom(sock) != SM_OK || SMTP_quit(sock))
343 static int handle_smtp_report(struct query *ctl, struct msgblk *msg)
344 /* handle SMTP errors based on the content of SMTP_response */
345 /* return of PS_REFUSED deletes mail from the server; PS_TRANSIENT keeps it */
347 int smtperr = atoi(smtp_response);
350 xalloca(responses[0], char *, strlen(smtp_response)+1);
351 strcpy(responses[0], smtp_response);
355 * Don't do this! It can really mess you up if, for example, you're
356 * reporting an error with a single RCPT TO address among several;
357 * RSET discards the message body and it doesn't get sent to the
360 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
361 if (outlevel >= O_DEBUG)
362 report(stdout, GT_("Saved error is still %d\n"), smtperr);
363 #endif /* __UNUSED */
366 * Note: send_bouncemail message strings are not made subject
367 * to gettext translation because (a) they're going to be
368 * embedded in a text/plain 7bit part, and (b) they're
369 * going to be associated with listener error-response
370 * messages, which are probably in English (none of the
371 * MTAs I know about are internationalized).
373 if (str_find(&ctl->antispam, smtperr))
376 * SMTP listener explicitly refuses to deliver mail
377 * coming from this address, probably due to an
378 * anti-spam domain exclusion. Respect this. Don't
379 * try to ship the message, and don't prevent it from
380 * being deleted. There's no point in bouncing the
381 * email either since most spammers don't put their
382 * real return email address anywhere in the headers
383 * (unless the user insists with the SET SPAMBOUNCE
388 * 571 = sendmail's "unsolicited email refused"
389 * 550 = exim's new antispam response (temporary)
390 * 501 = exim's old antispam response
391 * 554 = Postfix antispam response.
395 send_bouncemail(ctl, msg, XMIT_ACCEPT,
396 "Our spam filter rejected this transaction.\r\n",
402 * Suppress error message only if the response specifically
403 * meant `excluded for policy reasons'. We *should* see
404 * an error when the return code is less specific.
407 report(stderr, GT_("%cMTP error: %s\n"),
413 case 552: /* message exceeds fixed maximum message size */
415 * Permanent no-go condition on the
416 * ESMTP server. Don't try to ship the message,
417 * and allow it to be deleted.
420 send_bouncemail(ctl, msg, XMIT_ACCEPT,
421 "This message was too large (SMTP error 552).\r\n",
425 case 553: /* invalid sending domain */
427 * These latter days 553 usually means a spammer is trying to
428 * cover his tracks. We never bouncemail on these, because
429 * (a) the return address is invalid by definition, and
430 * (b) we wouldn't want spammers to get confirmation that
431 * this address is live, anyway.
433 #ifdef __DONT_FEED_THE_SPAMMERS__
435 send_bouncemail(ctl, msg, XMIT_ACCEPT,
436 "Invalid address in MAIL FROM (SMTP error 553).\r\n",
438 #endif /* __DONT_FEED_THE_SPAMMERS__ */
442 /* bounce non-transient errors back to the sender */
443 if (smtperr >= 500 && smtperr <= 599)
444 if (send_bouncemail(ctl, msg, XMIT_ACCEPT,
445 "General SMTP/ESMTP error.\r\n",
447 return(run.bouncemail ? PS_REFUSED : PS_TRANSIENT);
449 * We're going to end up here on 4xx errors, like:
451 * 451: temporarily unable to identify sender (exim)
452 * 452: temporary out-of-queue-space condition on the ESMTP server.
454 * These are temporary errors. Don't try to ship the message,
455 * and suppress deletion so it can be retried on a future
458 * Bouncemail *might* be appropriate here as a delay
459 * notification (note; if we ever add this, we must make
460 * sure the RFC1894 Action field is "delayed" rather than
461 * "failed"). But it's not really necessary because
462 * these are not actual failures, we're very likely to be
463 * able to recover on the next cycle.
465 return(PS_TRANSIENT);
469 /* these are shared by open_sink and stuffline */
472 int stuffline(struct query *ctl, char *buf)
473 /* ship a line to the given control block's output sink (SMTP server or MDA) */
478 /* The line may contain NUL characters. Find the last char to use
479 * -- the real line termination is the sequence "\n\0".
482 while ((last += strlen(last)) && (last[-1] != '\n'))
485 /* fix message lines that have only \n termination (for qmail) */
488 if (last - 1 == buf || last[-2] != '\r')
497 phase = FORWARDING_WAIT;
500 * SMTP byte-stuffing. We only do this if the protocol does *not*
501 * use .<CR><LF> as EOM. If it does, the server will already have
502 * decorated any . lines it sends back up.
506 if (ctl->server.base_protocol->delimited) /* server has already byte-stuffed */
511 /* writing to SMTP, leave the byte-stuffing in place */;
513 else /* if (!protocol->delimited) -- not byte-stuffed already */
516 SockWrite(ctl->smtp_socket, buf, 1); /* byte-stuff it */
518 /* leave it alone */;
522 /* we may need to strip carriage returns */
527 for (sp = tp = buf; sp < last; sp++)
535 if (ctl->mda || ctl->bsmtp)
536 n = fwrite(buf, 1, last - buf, sinkfp);
537 else if (ctl->smtp_socket != -1)
538 n = SockWrite(ctl->smtp_socket, buf, last - buf);
545 static int open_bsmtp_sink(struct query *ctl, struct msgblk *msg,
546 int *good_addresses, int *bad_addresses)
547 /* open a BSMTP stream */
551 if (strcmp(ctl->bsmtp, "-") == 0)
554 sinkfp = fopen(ctl->bsmtp, "a");
556 /* see the ap computation under the SMTP branch */
558 "MAIL FROM: %s", (msg->return_path[0]) ? msg->return_path : user);
560 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
561 fputs(" BODY=8BITMIME", sinkfp);
562 else if (ctl->mimemsg & MSG_IS_7BIT)
563 fputs(" BODY=7BIT", sinkfp);
565 /* exim's BSMTP processor does not handle SIZE */
566 /* fprintf(sinkfp, " SIZE=%d", msg->reallen); */
568 fprintf(sinkfp, "\r\n");
571 * RFC 1123 requires that the domain name part of the
572 * RCPT TO address be "canonicalized", that is a FQDN
573 * or MX but not a CNAME. Some listeners (like exim)
574 * enforce this. Now that we have the actual hostname,
575 * compute what we should canonicalize with.
577 ctl->destaddr = ctl->smtpaddress ? ctl->smtpaddress : "localhost";
580 for (idp = msg->recipients; idp; idp = idp->next)
581 if (idp->val.status.mark == XMIT_ACCEPT)
584 fprintf(sinkfp, "RCPT TO: %s\r\n", ctl->smtpname);
585 else if (strchr(idp->id, '@'))
587 "RCPT TO: %s\r\n", idp->id);
590 "RCPT TO: %s@%s\r\n", idp->id, ctl->destaddr);
594 fputs("DATA\r\n", sinkfp);
598 report(stderr, GT_("BSMTP file open or preamble write failed\n"));
605 /* this is experimental and will be removed if double bounces are reported */
606 #define EXPLICIT_BOUNCE_ON_BAD_ADDRESS
608 static int open_smtp_sink(struct query *ctl, struct msgblk *msg,
609 int *good_addresses, int *bad_addresses)
610 /* open an SMTP stream */
614 char options[MSGBUFSIZE];
615 char addr[HOSTLEN+USERNAMELEN+1];
616 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
617 char **from_responses;
618 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
622 * Compute ESMTP options.
625 if (ctl->server.esmtp_options & ESMTP_8BITMIME) {
626 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
627 strcpy(options, " BODY=8BITMIME");
628 else if (ctl->mimemsg & MSG_IS_7BIT)
629 strcpy(options, " BODY=7BIT");
632 if ((ctl->server.esmtp_options & ESMTP_SIZE) && msg->reallen > 0)
633 sprintf(options + strlen(options), " SIZE=%d", msg->reallen);
636 * Try to get the SMTP listener to take the Return-Path
637 * address as MAIL FROM. If it won't, fall back on the
638 * remotename and mailserver host. This won't affect replies,
639 * which use the header From address anyway; the MAIL FROM
640 * address is a place for the SMTP listener to send
641 * bouncemail. The point is to guarantee a FQDN in the MAIL
642 * FROM line -- some SMTP listeners, like smail, become
645 * RFC 1123 requires that the domain name part of the
646 * MAIL FROM address be "canonicalized", that is a
647 * FQDN or MX but not a CNAME. We'll assume the Return-Path
648 * header is already in this form here (it certainly
649 * is if rewrite is on). RFC 1123 is silent on whether
650 * a nonexistent hostname part is considered canonical.
652 * This is a potential problem if the MTAs further upstream
653 * didn't pass canonicalized From/Return-Path lines, *and* the
654 * local SMTP listener insists on them.
656 * Handle the case where an upstream MTA is setting a return
657 * path equal to "@". Ghod knows why anyone does this, but
658 * it's been reported to happen in mail from Amazon.com and
661 if (!msg->return_path[0] || (0 == strcmp(msg->return_path, "@")))
664 snprintf(addr, sizeof(addr),
667 #endif /* HAVE_SNPRINTF */
668 "%s@%s", ctl->remotename, ctl->server.truename);
671 else if (strchr(msg->return_path,'@') || strchr(msg->return_path,'!'))
672 ap = msg->return_path;
673 else /* in case Return-Path existed but was local */
676 snprintf(addr, sizeof(addr),
679 #endif /* HAVE_SNPRINTF */
680 "%s@%s", msg->return_path, ctl->server.truename);
684 if (SMTP_from(ctl->smtp_socket, ap, options) != SM_OK)
686 int err = handle_smtp_report(ctl, msg);
688 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
693 * Now list the recipient addressees
696 for (idp = msg->recipients; idp; idp = idp->next)
698 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
699 xalloca(from_responses, char **, sizeof(char *) * total_addresses);
700 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
701 for (idp = msg->recipients; idp; idp = idp->next)
702 if (idp->val.status.mark == XMIT_ACCEPT)
704 if (strchr(idp->id, '@'))
705 strcpy(addr, idp->id);
709 snprintf(addr, sizeof(addr), "%s", ctl->smtpname);
711 sprintf(addr, "%s", ctl->smtpname);
712 #endif /* HAVE_SNPRINTF */
716 snprintf(addr, sizeof(addr), "%s@%s", idp->id, ctl->destaddr);
718 sprintf(addr, "%s@%s", idp->id, ctl->destaddr);
719 #endif /* HAVE_SNPRINTF */
722 if (SMTP_rcpt(ctl->smtp_socket, addr) == SM_OK)
726 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
727 char errbuf[POPBUFSIZE];
728 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
729 handle_smtp_report(ctl, msg);
731 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
733 snprintf(errbuf, sizeof(errbuf), "%s: %s",
734 idp->id, smtp_response);
736 strncpy(errbuf, idp->id, sizeof(errbuf));
737 strcat(errbuf, ": ");
738 strcat(errbuf, smtp_response);
739 #endif /* HAVE_SNPRINTF */
741 xalloca(from_responses[*bad_addresses],
744 strcpy(from_responses[*bad_addresses], errbuf);
745 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
748 idp->val.status.mark = XMIT_RCPTBAD;
749 if (outlevel >= O_VERBOSE)
751 GT_("%cMTP listener doesn't like recipient address `%s'\n"),
752 ctl->listener, addr);
756 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
758 * This should not be necessary, because the SMTP listener itself
759 * should genrate a bounce for the bad address.
762 send_bouncemail(ctl, msg, XMIT_RCPTBAD,
763 "Some addresses were rejected by the MDA fetchmail forwards to.\r\n",
764 *bad_addresses, from_responses);
765 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
768 * It's tempting to do local notification only if bouncemail was
769 * insufficient -- that is, to add && total_addresses > *bad_addresses
770 * to the test here. The problem with this theory is that it would
771 * make initial diagnosis of a broken multidrop configuration very
772 * hard -- most single-recipient messages would just invisibly bounce.
774 if (!(*good_addresses))
776 if (!run.postmaster[0])
778 if (outlevel >= O_VERBOSE)
779 report(stderr, GT_("no address matches; no postmaster set.\n"));
780 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
783 if (strchr(run.postmaster, '@'))
784 strncpy(addr, run.postmaster, sizeof(addr));
788 snprintf(addr, sizeof(addr), "%s@%s", run.postmaster, ctl->destaddr);
790 sprintf(addr, "%s@%s", run.postmaster, ctl->destaddr);
791 #endif /* HAVE_SNPRINTF */
794 if (SMTP_rcpt(ctl->smtp_socket, addr) != SM_OK)
796 report(stderr, GT_("can't even send to %s!\n"), run.postmaster);
797 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
801 if (outlevel >= O_VERBOSE)
802 report(stderr, GT_("no address matches; forwarding to %s.\n"), run.postmaster);
806 * Tell the listener we're ready to send data.
807 * Some listeners (like zmailer) may return antispam errors here.
809 if (SMTP_data(ctl->smtp_socket) != SM_OK)
811 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
812 return(handle_smtp_report(ctl, msg));
816 * We need to stash this away in order to know how many
817 * response lines to expect after the LMTP end-of-message.
819 lmtp_responses = *good_addresses;
824 static int open_mda_sink(struct query *ctl, struct msgblk *msg,
825 int *good_addresses, int *bad_addresses)
826 /* open a stream to a local MDA */
828 #ifdef HAVE_SIGACTION
829 struct sigaction sa_new;
830 #endif /* HAVE_SIGACTION */
832 int length = 0, fromlen = 0, nameslen = 0;
833 char *names = NULL, *before, *after, *from = NULL;
835 ctl->destaddr = "localhost";
837 for (idp = msg->recipients; idp; idp = idp->next)
838 if (idp->val.status.mark == XMIT_ACCEPT)
841 length = strlen(ctl->mda);
842 before = xstrdup(ctl->mda);
844 /* get user addresses for %T (or %s for backward compatibility) */
845 if (strstr(before, "%s") || strstr(before, "%T"))
848 * We go through this in order to be able to handle very
849 * long lists of users and (re)implement %s.
852 for (idp = msg->recipients; idp; idp = idp->next)
853 if ((idp->val.status.mark == XMIT_ACCEPT))
854 nameslen += (strlen(idp->id) + 1); /* string + ' ' */
855 if ((*good_addresses == 0))
856 nameslen = strlen(run.postmaster);
858 names = (char *)xmalloc(nameslen + 1); /* account for '\0' */
859 if (*good_addresses == 0)
860 strcpy(names, run.postmaster);
864 for (idp = msg->recipients; idp; idp = idp->next)
865 if (idp->val.status.mark == XMIT_ACCEPT)
867 strcat(names, idp->id);
870 names[--nameslen] = '\0'; /* chop trailing space */
873 /* sanitize names in order to contain only harmless shell chars */
877 /* get From address for %F */
878 if (strstr(before, "%F"))
880 from = xstrdup(msg->return_path);
882 /* sanitize from in order to contain *only* harmless shell chars */
885 fromlen = strlen(from);
888 /* do we have to build an mda string? */
893 /* find length of resulting mda string */
895 while ((sp = strstr(sp, "%s"))) {
896 length += nameslen - 2; /* subtract %s */
900 while ((sp = strstr(sp, "%T"))) {
901 length += nameslen - 2; /* subtract %T */
905 while ((sp = strstr(sp, "%F"))) {
906 length += fromlen - 2; /* subtract %F */
910 after = xmalloc(length + 1);
912 /* copy mda source string to after, while expanding %[sTF] */
913 for (dp = after, sp = before; (*dp = *sp); dp++, sp++) {
914 if (sp[0] != '%') continue;
916 /* need to expand? BTW, no here overflow, because in
917 ** the worst case (end of string) sp[1] == '\0' */
918 if (sp[1] == 's' || sp[1] == 'T') {
921 sp++; /* position sp over [sT] */
922 dp--; /* adjust dp */
923 } else if (sp[1] == 'F') {
926 sp++; /* position sp over F */
927 dp--; /* adjust dp */
946 if (outlevel >= O_DEBUG)
947 report(stdout, GT_("about to deliver with: %s\n"), before);
951 * Arrange to run with user's permissions if we're root.
952 * This will initialize the ownership of any files the
953 * MDA creates properly. (The seteuid call is available
954 * under all BSDs and Linux)
957 #endif /* HAVE_SETEUID */
959 sinkfp = popen(before, "w");
964 /* this will fail quietly if we didn't start as root */
966 #endif /* HAVE_SETEUID */
970 report(stderr, GT_("MDA open failed\n"));
975 * We need to disable the normal SIGCHLD handling here because
976 * sigchld_handler() would reap away the error status, returning
977 * error status instead of 0 for successful completion.
979 #ifndef HAVE_SIGACTION
980 signal(SIGCHLD, SIG_DFL);
982 memset (&sa_new, 0, sizeof sa_new);
983 sigemptyset (&sa_new.sa_mask);
984 sa_new.sa_handler = SIG_DFL;
985 sigaction (SIGCHLD, &sa_new, NULL);
986 #endif /* HAVE_SIGACTION */
991 int open_sink(struct query *ctl, struct msgblk *msg,
992 int *good_addresses, int *bad_addresses)
993 /* set up sinkfp to be an input sink we can ship a message to */
995 *bad_addresses = *good_addresses = 0;
997 if (ctl->bsmtp) /* dump to a BSMTP batch file */
998 return(open_bsmtp_sink(ctl, msg, good_addresses, bad_addresses));
1000 * Try to forward to an SMTP or LMTP listener. If the attempt to
1001 * open a socket fails, fall through to attempt delivery via
1004 else if (!ctl->mda && smtp_open(ctl) != -1)
1005 return(open_smtp_sink(ctl, msg, good_addresses, bad_addresses));
1008 * Awkward case. User didn't specify an MDA. Our attempt to get a
1009 * listener socket failed. Try to cope anyway -- initial configuration
1010 * may have found procmail.
1014 report(stderr, GT_("%cMTP connect to %s failed\n"),
1016 ctl->smtphost ? ctl->smtphost : "localhost");
1018 #ifndef FALLBACK_MDA
1019 /* No fallback MDA declared. Bail out. */
1023 * If user had things set up to forward offsite, no way
1024 * we want to deliver locally!
1026 if (ctl->smtphost && strcmp(ctl->smtphost, "localhost"))
1030 * User was delivering locally. We have a fallback MDA.
1031 * Latch it in place, logging the error, and fall through.
1033 ctl->mda = FALLBACK_MDA;
1035 report(stderr, GT_("can't raise the listener; falling back to %s"),
1040 if (ctl->mda) /* must deliver through an MDA */
1041 return(open_mda_sink(ctl, msg, good_addresses, bad_addresses));
1046 void release_sink(struct query *ctl)
1047 /* release the per-message output sink, whether it's a pipe or SMTP socket */
1049 if (ctl->bsmtp && sinkfp)
1056 sinkfp = (FILE *)NULL;
1058 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1062 int close_sink(struct query *ctl, struct msgblk *msg, flag forward)
1063 /* perform end-of-message actions on the current output sink */
1069 /* close the delivery pipe, we'll reopen before next message */
1072 rc = pclose(sinkfp);
1073 sinkfp = (FILE *)NULL;
1078 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1083 GT_("MDA returned nonzero status %d\n"), rc);
1087 else if (ctl->bsmtp && sinkfp)
1091 /* implicit disk-full check here... */
1092 fputs(".\r\n", sinkfp);
1093 error = ferror(sinkfp);
1094 if (strcmp(ctl->bsmtp, "-"))
1095 if (fclose(sinkfp) == EOF) error = 1;
1099 GT_("Message termination or close of BSMTP file failed\n"));
1105 /* write message terminator */
1106 if (SMTP_eom(ctl->smtp_socket) != SM_OK)
1108 if (handle_smtp_report(ctl, msg) != PS_REFUSED)
1110 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1115 report(stderr, GT_("SMTP listener refused delivery\n"));
1116 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1122 * If this is an SMTP connection, SMTP_eom() ate the response.
1123 * But could be this is an LMTP connection, in which case we have to
1124 * interpret either (a) a single 503 response meaning there
1125 * were no successful RCPT TOs, or (b) a variable number of
1126 * responses, one for each successful RCPT TO. We need to send
1127 * bouncemail on each failed response and then return TRUE anyway,
1128 * otherwise the message will get left in the queue and resent
1129 * to people who got it the first time.
1131 if (ctl->listener == LMTP_MODE)
1133 if (lmtp_responses == 0)
1135 SMTP_ok(ctl->smtp_socket);
1138 * According to RFC2033, 503 is the only legal response
1139 * if no RCPT TO commands succeeded. No error recovery
1140 * is really possible here, as we have no idea what
1141 * insane thing the listener might be doing if it doesn't
1144 if (atoi(smtp_response) == 503)
1145 report(stderr, GT_("LMTP delivery error on EOM\n"));
1148 GT_("Unexpected non-503 response to LMTP EOM: %s\n"),
1152 * It's not completely clear what to do here. We choose to
1153 * interpret delivery failure here as a transient error,
1154 * the same way SMTP delivery failure is handled. If we're
1155 * wrong, an undead message will get stuck in the queue.
1164 /* eat the RFC2033-required responses, saving errors */
1165 xalloca(responses, char **, sizeof(char *) * lmtp_responses);
1166 for (errors = i = 0; i < lmtp_responses; i++)
1168 if (SMTP_ok(ctl->smtp_socket) == SM_OK)
1169 responses[i] = (char *)NULL;
1172 xalloca(responses[errors],
1174 strlen(smtp_response)+1);
1175 strcpy(responses[errors], smtp_response);
1181 return(TRUE); /* all deliveries succeeded */
1184 * One or more deliveries failed.
1185 * If we can bounce a failures list back to the
1186 * sender, and the postmaster does not want to
1187 * deal with the bounces return TRUE, deleting the
1188 * message from the server so it won't be
1189 * re-forwarded on subsequent poll cycles.
1191 return(send_bouncemail(ctl, msg, XMIT_ACCEPT,
1192 "LSMTP partial delivery failure.\r\n",
1193 errors, responses));
1201 int open_warning_by_mail(struct query *ctl, struct msgblk *msg)
1202 /* set up output sink for a mailed warning to calling user */
1207 * Dispatching warning email is a little complicated. The problem is
1208 * that we have to deal with three distinct cases:
1210 * 1. Single-drop running from user account. Warning mail should
1211 * go to the local name for which we're collecting (coincides
1212 * with calling user).
1214 * 2. Single-drop running from root or other privileged ID, with rc
1215 * file generated on the fly (Ken Estes's weird setup...) Mail
1216 * should go to the local name for which we're collecting (does not
1217 * coincide with calling user).
1219 * 3. Multidrop. Mail must go to postmaster. We leave the recipients
1220 * member null so this message will fall through to run.postmaster.
1222 * The zero in the reallen element means we won't pass a SIZE
1223 * option to ESMTP; the message length would be more trouble than
1224 * it's worth to compute.
1226 struct msgblk reply = {NULL, NULL, "FETCHMAIL-DAEMON@", 0};
1229 strcat(reply.return_path, ctl->smtpaddress ? ctl->smtpaddress :
1232 if (!MULTIDROP(ctl)) /* send to calling user */
1234 save_str(&reply.recipients, ctl->localnames->id, XMIT_ACCEPT);
1235 status = open_sink(ctl, &reply, &good, &bad);
1236 free_str_list(&reply.recipients);
1238 else /* send to postmaster */
1239 status = open_sink(ctl, &reply, &good, &bad);
1240 stuff_warning(ctl, "Date: %s", rfc822timestamp());
1244 #if defined(HAVE_STDARG_H)
1245 void stuff_warning(struct query *ctl, const char *fmt, ... )
1247 void stuff_warning(struct query *ctl, fmt, va_alist)
1249 const char *fmt; /* printf-style format */
1252 /* format and ship a warning message line by mail */
1254 char buf[POPBUFSIZE];
1258 * stuffline() requires its input to be writeable (for CR stripping),
1259 * so we needed to copy the message to a writeable buffer anyway in
1260 * case it was a string constant. We make a virtue of that necessity
1261 * here by supporting stdargs/varargs.
1263 #if defined(HAVE_STDARG_H)
1268 #ifdef HAVE_VSNPRINTF
1269 vsnprintf(buf, sizeof(buf), fmt, ap);
1271 vsprintf(buf, fmt, ap);
1275 #ifdef HAVE_SNPRINTF
1276 snprintf(buf+strlen(buf), sizeof(buf)-strlen(buf), "\r\n");
1278 strcat(buf, "\r\n");
1279 #endif /* HAVE_SNPRINTF */
1281 stuffline(ctl, buf);
1284 void close_warning_by_mail(struct query *ctl, struct msgblk *msg)
1285 /* sign and send mailed warnings */
1287 stuff_warning(ctl, GT_("--\r\n\t\t\t\tThe Fetchmail Daemon\r\n"));
1288 close_sink(ctl, msg, TRUE);
1291 /* sink.c ends here */