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 int smtp_open(struct query *ctl)
50 /* try to open a socket to the appropriate SMTP server for this query */
52 char *parsed_host = NULL;
54 /* maybe it's time to close the socket in order to force delivery */
55 if (NUM_NONZERO(ctl->batchlimit) && (ctl->smtp_socket != -1) && ++batchcount == ctl->batchlimit)
57 SockClose(ctl->smtp_socket);
58 ctl->smtp_socket = -1;
62 /* if no socket to any SMTP host is already set up, try to open one */
63 if (ctl->smtp_socket == -1)
66 * RFC 1123 requires that the domain name in HELO address is a
67 * "valid principal domain name" for the client host. If we're
68 * running in invisible mode, violate this with malice
69 * aforethought in order to make the Received headers and
72 * In fact this code relies on the RFC1123 requirement that the
73 * SMTP listener must accept messages even if verification of the
74 * HELO name fails (RFC1123 section 5.2.5, paragraph 2).
76 * How we compute the true mailhost name to pass to the
77 * listener doesn't affect behavior on RFC1123-violating
78 * listeners that check for name match; we're going to lose
79 * on those anyway because we can never give them a name
80 * that matches the local machine fetchmail is running on.
81 * What it will affect is the listener's logging.
84 const char *id_me = run.invisible ? ctl->server.truename : fetchmailhost;
90 * Run down the SMTP hunt list looking for a server that's up.
91 * Use both explicit hunt entries (value TRUE) and implicit
92 * (default) ones (value FALSE).
95 phase = LISTENER_WAIT;
97 set_timeout(ctl->server.timeout);
98 for (idp = ctl->smtphunt; idp; idp = idp->next)
102 char *portnum = SMTP_PORT;
104 int portnum = SMTP_PORT;
105 #endif /* INET6_ENABLE */
107 xalloca(parsed_host, char *, strlen(idp->id) + 1);
109 ctl->smtphost = idp->id; /* remember last host tried. */
110 if(ctl->smtphost[0]=='/')
111 ctl->listener = LMTP_MODE;
113 strcpy(parsed_host, idp->id);
114 if ((cp = strrchr(parsed_host, '/')))
121 #endif /* INET6_ENABLE */
124 if (ctl->smtphost[0]=='/'){
125 if((ctl->smtp_socket = UnixOpen(ctl->smtphost))==-1)
128 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,NULL,
129 ctl->server.plugout)) == -1)
132 /* return immediately for ODMR */
133 if (ctl->server.protocol == P_ODMR)
134 return(ctl->smtp_socket); /* success */
136 /* are we doing SMTP or LMTP? */
137 SMTP_setmode(ctl->listener);
139 /* first, probe for ESMTP */
140 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
141 SMTP_ehlo(ctl->smtp_socket, id_me,
142 &ctl->server.esmtp_options) == SM_OK)
146 * RFC 1869 warns that some listeners hang up on a failed EHLO,
147 * so it's safest not to assume the socket will still be good.
149 SockClose(ctl->smtp_socket);
150 ctl->smtp_socket = -1;
152 /* if opening for ESMTP failed, try SMTP */
153 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,NULL,
154 ctl->server.plugout)) == -1)
157 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
158 SMTP_helo(ctl->smtp_socket, id_me) == SM_OK)
161 SockClose(ctl->smtp_socket);
162 ctl->smtp_socket = -1;
169 * RFC 1123 requires that the domain name part of the
170 * RCPT TO address be "canonicalized", that is a FQDN
171 * or MX but not a CNAME. Some listeners (like exim)
172 * enforce this. Now that we have the actual hostname,
173 * compute what we should canonicalize with.
175 * make sure we do not forget to drop the /port if
178 if (ctl->listener == LMTP_MODE && !ctl->smtpaddress)
180 if (parsed_host && parsed_host[0] != 0)
181 ctl->destaddr = xstrdup(parsed_host);
183 ctl->destaddr = (ctl->smtphost && ctl->smtphost[0] != '/') ? ctl->smtphost : "localhost";
186 ctl->destaddr = ctl->smtpaddress ? ctl->smtpaddress : ( ctl->smtphost && ctl->smtphost[0] != '/' ? ctl->smtphost : "localhost");
188 if (outlevel >= O_DEBUG && ctl->smtp_socket != -1)
189 report(stdout, GT_("forwarding to %s\n"), ctl->smtphost);
191 return(ctl->smtp_socket);
194 static void sanitize(char *s)
195 /* replace unsafe shellchars by an _ */
197 const static char *ok_chars = " 1234567890!@%-_=+:,./abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
200 for (cp = s; *(cp += strspn(cp, ok_chars)); /* NO INCREMENT */)
204 static int send_bouncemail(struct query *ctl, struct msgblk *msg,
205 int userclass, char *message,
206 int nerrors, char *errors[])
207 /* bounce back an error report a la RFC 1892 */
209 char daemon_name[18 + HOSTLEN] = "FETCHMAIL-DAEMON@";
210 char boundary[BUFSIZ], *bounce_to;
213 /* don't bounce in reply to undeliverable bounces */
214 if (!msg->return_path[0] || strcmp(msg->return_path, "<>") == 0)
217 bounce_to = (run.bouncemail ? msg->return_path : run.postmaster);
219 SMTP_setmode(SMTP_MODE);
221 /* can't just use fetchmailhost here, it might be localhost */
222 strcat(daemon_name, host_fqdn());
224 /* we need only SMTP for this purpose */
225 if ((sock = SockOpen("localhost", SMTP_PORT, NULL, NULL)) == -1
226 || SMTP_ok(sock) != SM_OK
227 || SMTP_helo(sock, fetchmailhost) != SM_OK
228 || SMTP_from(sock, daemon_name, (char *)NULL) != SM_OK
229 || SMTP_rcpt(sock, bounce_to) != SM_OK
230 || SMTP_data(sock) != SM_OK)
233 /* our first duty is to keep the sacred foo counters turning... */
235 snprintf(boundary, sizeof(boundary),
238 #endif /* HAVE_SNPRINTF */
239 "foo-mani-padme-hum-%d-%d-%ld",
240 (int)getpid(), (int)getppid(), time((time_t *)NULL));
242 if (outlevel >= O_VERBOSE)
243 report(stdout, GT_("SMTP: (bounce-message body)\n"));
245 /* this will usually go to sylog... */
246 report(stderr, GT_("mail from %s bounced to %s\n"),
247 daemon_name, bounce_to);
249 /* bouncemail headers */
250 SockPrintf(sock, "Return-Path: <>\r\n");
251 SockPrintf(sock, "From: %s\r\n", daemon_name);
252 SockPrintf(sock, "To: %s\r\n", bounce_to);
253 SockPrintf(sock, "MIME-Version: 1.0\r\n");
254 SockPrintf(sock, "Content-Type: multipart/report; report-type=delivery-status;\r\n\tboundary=\"%s\"\r\n", boundary);
255 SockPrintf(sock, "\r\n");
257 /* RFC1892 part 1 -- human-readable message */
258 SockPrintf(sock, "--%s\r\n", boundary);
259 SockPrintf(sock,"Content-Type: text/plain\r\n");
260 SockPrintf(sock, "\r\n");
261 SockWrite(sock, message, strlen(message));
262 SockPrintf(sock, "\r\n");
263 SockPrintf(sock, "\r\n");
270 /* RFC1892 part 2 -- machine-readable responses */
271 SockPrintf(sock, "--%s\r\n", boundary);
272 SockPrintf(sock,"Content-Type: message/delivery-status\r\n");
273 SockPrintf(sock, "\r\n");
274 SockPrintf(sock, "Reporting-MTA: dns; %s\r\n", fetchmailhost);
277 for (idp = msg->recipients; idp; idp = idp->next)
278 if (idp->val.status.mark == userclass)
281 /* Minimum RFC1894 compliance + Diagnostic-Code field */
282 SockPrintf(sock, "\r\n");
283 SockPrintf(sock, "Final-Recipient: rfc822; %s@%s\r\n",
284 idp->id, fetchmailhost);
285 SockPrintf(sock, "Last-Attempt-Date: %s\r\n", rfc822timestamp());
286 SockPrintf(sock, "Action: failed\r\n");
289 /* one error applies to all users */
291 else if (nerrors > nusers)
293 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
297 /* errors correspond 1-1 to selected users */
298 error = errors[nusers++];
300 if (strlen(error) > 9 && isdigit(error[4])
301 && error[5] == '.' && isdigit(error[6])
302 && error[7] == '.' && isdigit(error[8]))
303 /* Enhanced status code available, use it */
304 SockPrintf(sock, "Status: %5.5s\r\n", &(error[4]));
306 /* Enhanced status code not available, fake one */
307 SockPrintf(sock, "Status: %c.0.0\r\n", error[0]);
308 SockPrintf(sock, "Diagnostic-Code: %s\r\n", error);
310 SockPrintf(sock, "\r\n");
313 /* RFC1892 part 3 -- headers of undelivered message */
314 SockPrintf(sock, "--%s\r\n", boundary);
315 SockPrintf(sock, "Content-Type: text/rfc822-headers\r\n");
316 SockPrintf(sock, "\r\n");
317 SockWrite(sock, msg->headers, strlen(msg->headers));
318 SockPrintf(sock, "\r\n");
319 SockPrintf(sock, "--%s--\r\n", boundary);
321 if (SMTP_eom(sock) != SM_OK || SMTP_quit(sock))
329 static int handle_smtp_report(struct query *ctl, struct msgblk *msg)
330 /* handle SMTP errors based on the content of SMTP_response */
331 /* return of PS_REFUSED deletes mail from the server; PS_TRANSIENT keeps it */
333 int smtperr = atoi(smtp_response);
336 xalloca(responses[0], char *, strlen(smtp_response)+1);
337 strcpy(responses[0], smtp_response);
341 * Don't do this! It can really mess you up if, for example, you're
342 * reporting an error with a single RCPT TO address among several;
343 * RSET discards the message body and it doesn't get sent to the
346 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
347 if (outlevel >= O_DEBUG)
348 report(stdout, GT_("Saved error is still %d\n"), smtperr);
349 #endif /* __UNUSED */
352 * Note: send_bouncemail message strings are not made subject
353 * to gettext translation because (a) they're going to be
354 * embedded in a text/plain 7bit part, and (b) they're
355 * going to be associated with listener error-response
356 * messages, which are probably in English (none of the
357 * MTAs I know about are internationalized).
359 if (str_find(&ctl->antispam, smtperr))
362 * SMTP listener explicitly refuses to deliver mail
363 * coming from this address, probably due to an
364 * anti-spam domain exclusion. Respect this. Don't
365 * try to ship the message, and don't prevent it from
366 * being deleted. There's no point in bouncing the
367 * email either since most spammers don't put their
368 * real return email address anywhere in the headers
369 * (unless the user insists with the SET SPAMBOUNCE
374 * 571 = sendmail's "unsolicited email refused"
375 * 550 = exim's new antispam response (temporary)
376 * 501 = exim's old antispam response
377 * 554 = Postfix antispam response.
381 send_bouncemail(ctl, msg, XMIT_ACCEPT,
382 "Our spam filter rejected this transaction.\r\n",
388 * Suppress error message only if the response specifically
389 * meant `excluded for policy reasons'. We *should* see
390 * an error when the return code is less specific.
393 report(stderr, GT_("%cMTP error: %s\n"),
399 case 552: /* message exceeds fixed maximum message size */
401 * Permanent no-go condition on the
402 * ESMTP server. Don't try to ship the message,
403 * and allow it to be deleted.
405 send_bouncemail(ctl, msg, XMIT_ACCEPT,
406 "This message was too large (SMTP error 552).\r\n",
408 return(run.bouncemail ? PS_REFUSED : PS_TRANSIENT);
410 case 553: /* invalid sending domain */
412 * These latter days 553 usually means a spammer is trying to
413 * cover his tracks. We never bouncemail on these, because
414 * (a) the return address is invalid by definition, and
415 * (b) we wouldn't want spammers to get confirmation that
416 * this address is live, anyway.
418 send_bouncemail(ctl, msg, XMIT_ACCEPT,
419 "Invalid address in MAIL FROM (SMTP error 553).\r\n",
424 /* bounce non-transient errors back to the sender */
425 if (smtperr >= 500 && smtperr <= 599)
426 if (send_bouncemail(ctl, msg, XMIT_ACCEPT,
427 "General SMTP/ESMTP error.\r\n",
429 return(run.bouncemail ? PS_REFUSED : PS_TRANSIENT);
431 * We're going to end up here on 4xx errors, like:
433 * 451: temporarily unable to identify sender (exim)
434 * 452: temporary out-of-queue-space condition on the ESMTP server.
436 * These are temporary errors. Don't try to ship the message,
437 * and suppress deletion so it can be retried on a future
440 * Bouncemail *might* be appropriate here as a delay
441 * notification (note; if we ever add this, we must make
442 * sure the RFC1894 Action field is "delayed" rather thwn
443 * "failed"). But it's not really necessary because
444 * these are not actual failures, we're very likely to be
445 * able to recover on the next cycle.
447 return(PS_TRANSIENT);
451 /* these are shared by open_sink and stuffline */
452 #ifndef HAVE_SIGACTION
453 static RETSIGTYPE (*sigchld)(int);
455 static struct sigaction sa_old;
456 #endif /* HAVE_SIGACTION */
459 int stuffline(struct query *ctl, char *buf)
460 /* ship a line to the given control block's output sink (SMTP server or MDA) */
465 /* The line may contain NUL characters. Find the last char to use
466 * -- the real line termination is the sequence "\n\0".
469 while ((last += strlen(last)) && (last[-1] != '\n'))
472 /* fix message lines that have only \n termination (for qmail) */
475 if (last - 1 == buf || last[-2] != '\r')
484 phase = FORWARDING_WAIT;
487 * SMTP byte-stuffing. We only do this if the protocol does *not*
488 * use .<CR><LF> as EOM. If it does, the server will already have
489 * decorated any . lines it sends back up.
493 if (ctl->server.base_protocol->delimited) /* server has already byte-stuffed */
498 /* writing to SMTP, leave the byte-stuffing in place */;
500 else /* if (!protocol->delimited) -- not byte-stuffed already */
503 SockWrite(ctl->smtp_socket, buf, 1); /* byte-stuff it */
505 /* leave it alone */;
509 /* we may need to strip carriage returns */
514 for (sp = tp = buf; sp < last; sp++)
522 if (ctl->mda || ctl->bsmtp)
523 n = fwrite(buf, 1, last - buf, sinkfp);
524 else if (ctl->smtp_socket != -1)
525 n = SockWrite(ctl->smtp_socket, buf, last - buf);
532 /* this is experimental and will be removed if double bounces are reported */
533 #define EXPLICIT_BOUNCE
535 int open_sink(struct query *ctl, struct msgblk *msg,
536 int *good_addresses, int *bad_addresses)
537 /* set up sinkfp to be an input sink we can ship a message to */
540 #ifdef HAVE_SIGACTION
541 struct sigaction sa_new;
542 #endif /* HAVE_SIGACTION */
544 *bad_addresses = *good_addresses = 0;
546 if (ctl->bsmtp) /* dump to a BSMTP batch file */
548 if (strcmp(ctl->bsmtp, "-") == 0)
551 sinkfp = fopen(ctl->bsmtp, "a");
553 /* see the ap computation under the SMTP branch */
555 "MAIL FROM: %s", (msg->return_path[0]) ? msg->return_path : user);
557 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
558 fputs(" BODY=8BITMIME", sinkfp);
559 else if (ctl->mimemsg & MSG_IS_7BIT)
560 fputs(" BODY=7BIT", sinkfp);
562 /* exim's BSMTP processor does not handle SIZE */
563 /* fprintf(sinkfp, " SIZE=%d", msg->reallen); */
565 fprintf(sinkfp, "\r\n");
568 * RFC 1123 requires that the domain name part of the
569 * RCPT TO address be "canonicalized", that is a FQDN
570 * or MX but not a CNAME. Some listeners (like exim)
571 * enforce this. Now that we have the actual hostname,
572 * compute what we should canonicalize with.
574 ctl->destaddr = ctl->smtpaddress ? ctl->smtpaddress : "localhost";
577 for (idp = msg->recipients; idp; idp = idp->next)
578 if (idp->val.status.mark == XMIT_ACCEPT)
581 fprintf(sinkfp, "RCPT TO: %s\r\n", ctl->smtpname);
582 else if (strchr(idp->id, '@'))
584 "RCPT TO: %s\r\n", idp->id);
587 "RCPT TO: %s@%s\r\n", idp->id, ctl->destaddr);
591 fputs("DATA\r\n", sinkfp);
595 report(stderr, GT_("BSMTP file open or preamble write failed\n"));
601 * Try to forward to an SMTP or LMTP listener. If the attempt to
602 * open a socket fails, fall through to attempt delivery via
605 else if (!ctl->mda && smtp_open(ctl) != -1)
608 char options[MSGBUFSIZE];
609 char addr[HOSTLEN+USERNAMELEN+1];
610 #ifdef EXPLICIT_BOUNCE
611 char **from_responses;
612 #endif /* EXPLICIT_BOUNCE */
616 * Compute ESMTP options.
619 if (ctl->server.esmtp_options & ESMTP_8BITMIME) {
620 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
621 strcpy(options, " BODY=8BITMIME");
622 else if (ctl->mimemsg & MSG_IS_7BIT)
623 strcpy(options, " BODY=7BIT");
626 if ((ctl->server.esmtp_options & ESMTP_SIZE) && msg->reallen > 0)
627 sprintf(options + strlen(options), " SIZE=%d", msg->reallen);
630 * Try to get the SMTP listener to take the Return-Path
631 * address as MAIL FROM. If it won't, fall back on the
632 * remotename and mailserver host. This won't affect replies,
633 * which use the header From address anyway; the MAIL FROM
634 * address is a place for the SMTP listener to send
635 * bouncemail. The point is to guarantee a FQDN in the MAIL
636 * FROM line -- some SMTP listeners, like smail, become
639 * RFC 1123 requires that the domain name part of the
640 * MAIL FROM address be "canonicalized", that is a
641 * FQDN or MX but not a CNAME. We'll assume the Return-Path
642 * header is already in this form here (it certainly
643 * is if rewrite is on). RFC 1123 is silent on whether
644 * a nonexistent hostname part is considered canonical.
646 * This is a potential problem if the MTAs further upstream
647 * didn't pass canonicalized From/Return-Path lines, *and* the
648 * local SMTP listener insists on them.
650 * Handle the case where an upstream MTA is setting a return
651 * path equal to "@". Ghod knows why anyone does this, but
652 * it's been reported to happen in mail from Amazon.com and
655 if (!msg->return_path[0] || (0 == strcmp(msg->return_path, "@")))
658 snprintf(addr, sizeof(addr),
661 #endif /* HAVE_SNPRINTF */
662 "%s@%s", ctl->remotename, ctl->server.truename);
665 else if (strchr(msg->return_path,'@') || strchr(msg->return_path,'!'))
666 ap = msg->return_path;
667 else /* in case Return-Path existed but was local */
670 snprintf(addr, sizeof(addr),
673 #endif /* HAVE_SNPRINTF */
674 "%s@%s", msg->return_path, ctl->server.truename);
678 if (SMTP_from(ctl->smtp_socket, ap, options) != SM_OK)
680 int err = handle_smtp_report(ctl, msg);
682 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
687 * Now list the recipient addressees
690 for (idp = msg->recipients; idp; idp = idp->next)
692 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
693 xalloca(from_responses, char **, sizeof(char *) * total_addresses);
694 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
695 for (idp = msg->recipients; idp; idp = idp->next)
696 if (idp->val.status.mark == XMIT_ACCEPT)
698 if (strchr(idp->id, '@'))
699 strcpy(addr, idp->id);
703 snprintf(addr, sizeof(addr)-1, "%s", ctl->smtpname);
705 sprintf(addr, "%s", ctl->smtpname);
706 #endif /* HAVE_SNPRINTF */
710 snprintf(addr, sizeof(addr)-1, "%s@%s", idp->id, ctl->destaddr);
712 sprintf(addr, "%s@%s", idp->id, ctl->destaddr);
713 #endif /* HAVE_SNPRINTF */
716 if (SMTP_rcpt(ctl->smtp_socket, addr) == SM_OK)
720 handle_smtp_report(ctl, msg);
722 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
724 snprintf(errbuf, sizeof(errbuf), "%s: %s",
725 idp->id, smtp_response);
727 strncpy(errbuf, idp->id, sizeof(errbuf));
728 strcat(errbuf, ": ");
729 strcat(errbuf, smtp_response);
730 #endif /* HAVE_SNPRINTF */
732 xalloca(from_responses[*bad_addresses],
735 strcpy(from_responses[*bad_addresses], errbuf);
736 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
739 idp->val.status.mark = XMIT_RCPTBAD;
740 if (outlevel >= O_VERBOSE)
742 GT_("%cMTP listener doesn't like recipient address `%s'\n"),
743 ctl->listener, addr);
747 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
749 * This should not be necessary, because the SMTP listener itself
750 * should genrate a bounce for the bad address.
753 send_bouncemail(ctl, msg, XMIT_RCPTBAD,
754 "Some addresses were rejected by the MDA fetchmail forwards to.\r\n",
755 *bad_addresses, from_responses);
756 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
759 * It's tempting to do local notification only if bouncemail was
760 * insufficient -- that is, to add && total_addresses > *bad_addresses
761 * to the test here. The problem with this theory is that it would
762 * make initial diagnosis of a broken multidrop configuration very
763 * hard -- most single-recipient messages would just invisibly bounce.
765 if (!(*good_addresses))
767 if (!run.postmaster[0])
769 if (outlevel >= O_VERBOSE)
770 report(stderr, GT_("no address matches; no postmaster set.\n"));
771 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
774 if (strchr(run.postmaster, '@'))
775 strncpy(addr, run.postmaster, sizeof(addr));
779 snprintf(addr, sizeof(addr)-1, "%s@%s", run.postmaster, ctl->destaddr);
781 sprintf(addr, "%s@%s", run.postmaster, ctl->destaddr);
782 #endif /* HAVE_SNPRINTF */
785 if (SMTP_rcpt(ctl->smtp_socket, addr) != SM_OK)
787 report(stderr, GT_("can't even send to %s!\n"), run.postmaster);
788 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
792 if (outlevel >= O_VERBOSE)
793 report(stderr, GT_("no address matches; forwarding to %s.\n"), run.postmaster);
797 * Tell the listener we're ready to send data.
798 * Some listeners (like zmailer) may return antispam errors here.
800 if (SMTP_data(ctl->smtp_socket) != SM_OK)
802 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
803 return(handle_smtp_report(ctl, msg));
808 * Awkward case. User didn't specify an MDA. Our attempt to get a
809 * listener socket failed. Try to cope anyway -- initial configuration
810 * may have found procmail.
814 report(stderr, GT_("%cMTP connect to %s failed\n"),
816 ctl->smtphost ? ctl->smtphost : "localhost");
819 /* No fallback MDA declared. Bail out. */
823 * If user had things set up to forward offsite, no way
824 * we want to deliver locally!
826 if (ctl->smtphost && strcmp(ctl->smtphost, "localhost"))
830 * User was delivering locally. We have a fallback MDA.
831 * Latch it in place, logging the error, and fall through.
833 ctl->mda = FALLBACK_MDA;
835 report(stderr, GT_("can't raise the listener; falling back to %s"),
840 if (ctl->mda) /* must deliver through an MDA */
842 int length = 0, fromlen = 0, nameslen = 0;
843 char *names = NULL, *before, *after, *from = NULL;
845 ctl->destaddr = "localhost";
847 for (idp = msg->recipients; idp; idp = idp->next)
848 if (idp->val.status.mark == XMIT_ACCEPT)
851 length = strlen(ctl->mda);
852 before = xstrdup(ctl->mda);
854 /* get user addresses for %T (or %s for backward compatibility) */
855 if (strstr(before, "%s") || strstr(before, "%T"))
858 * We go through this in order to be able to handle very
859 * long lists of users and (re)implement %s.
862 for (idp = msg->recipients; idp; idp = idp->next)
863 if ((idp->val.status.mark == XMIT_ACCEPT))
864 nameslen += (strlen(idp->id) + 1); /* string + ' ' */
865 if ((*good_addresses == 0))
866 nameslen = strlen(run.postmaster);
868 names = (char *)xmalloc(nameslen + 1); /* account for '\0' */
869 if (*good_addresses == 0)
870 strcpy(names, run.postmaster);
874 for (idp = msg->recipients; idp; idp = idp->next)
875 if (idp->val.status.mark == XMIT_ACCEPT)
877 strcat(names, idp->id);
880 names[--nameslen] = '\0'; /* chop trailing space */
883 /* sanitize names in order to contain only harmless shell chars */
887 /* get From address for %F */
888 if (strstr(before, "%F"))
890 from = xstrdup(msg->return_path);
892 /* sanitize from in order to contain *only* harmless shell chars */
895 fromlen = strlen(from);
898 /* do we have to build an mda string? */
903 /* find length of resulting mda string */
905 while ((sp = strstr(sp, "%s"))) {
906 length += nameslen - 2; /* subtract %s */
910 while ((sp = strstr(sp, "%T"))) {
911 length += nameslen - 2; /* subtract %T */
915 while ((sp = strstr(sp, "%F"))) {
916 length += fromlen - 2; /* subtract %F */
920 after = xmalloc(length + 1);
922 /* copy mda source string to after, while expanding %[sTF] */
923 for (dp = after, sp = before; (*dp = *sp); dp++, sp++) {
924 if (sp[0] != '%') continue;
926 /* need to expand? BTW, no here overflow, because in
927 ** the worst case (end of string) sp[1] == '\0' */
928 if (sp[1] == 's' || sp[1] == 'T') {
931 sp++; /* position sp over [sT] */
932 dp--; /* adjust dp */
933 } else if (sp[1] == 'F') {
936 sp++; /* position sp over F */
937 dp--; /* adjust dp */
956 if (outlevel >= O_DEBUG)
957 report(stdout, GT_("about to deliver with: %s\n"), before);
961 * Arrange to run with user's permissions if we're root.
962 * This will initialize the ownership of any files the
963 * MDA creates properly. (The seteuid call is available
964 * under all BSDs and Linux)
967 #endif /* HAVE_SETEUID */
969 sinkfp = popen(before, "w");
974 /* this will fail quietly if we didn't start as root */
976 #endif /* HAVE_SETEUID */
980 report(stderr, GT_("MDA open failed\n"));
985 * We need to disable the normal SIGCHLD handling here because
986 * sigchld_handler() would reap away the error status, returning
987 * error status instead of 0 for successful completion.
989 #ifndef HAVE_SIGACTION
990 sigchld = signal(SIGCHLD, SIG_DFL);
992 memset (&sa_new, 0, sizeof sa_new);
993 sigemptyset (&sa_new.sa_mask);
994 sa_new.sa_handler = SIG_DFL;
995 sigaction (SIGCHLD, &sa_new, NULL);
996 #endif /* HAVE_SIGACTION */
1000 * We need to stash this away in order to know how many
1001 * response lines to expect after the LMTP end-of-message.
1003 lmtp_responses = *good_addresses;
1008 void release_sink(struct query *ctl)
1009 /* release the per-message output sink, whether it's a pipe or SMTP socket */
1011 if (ctl->bsmtp && sinkfp)
1018 sinkfp = (FILE *)NULL;
1020 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1024 int close_sink(struct query *ctl, struct msgblk *msg, flag forward)
1025 /* perform end-of-message actions on the current output sink */
1031 /* close the delivery pipe, we'll reopen before next message */
1034 rc = pclose(sinkfp);
1035 sinkfp = (FILE *)NULL;
1040 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1045 GT_("MDA returned nonzero status %d\n"), rc);
1049 else if (ctl->bsmtp && sinkfp)
1053 /* implicit disk-full check here... */
1054 fputs(".\r\n", sinkfp);
1055 error = ferror(sinkfp);
1056 if (strcmp(ctl->bsmtp, "-"))
1057 if (fclose(sinkfp) == EOF) error = 1;
1061 GT_("Message termination or close of BSMTP file failed\n"));
1067 /* write message terminator */
1068 if (SMTP_eom(ctl->smtp_socket) != SM_OK)
1070 if (handle_smtp_report(ctl, msg) != PS_REFUSED)
1072 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1077 report(stderr, GT_("SMTP listener refused delivery\n"));
1078 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1084 * If this is an SMTP connection, SMTP_eom() ate the response.
1085 * But could be this is an LMTP connection, in which case we have to
1086 * interpret either (a) a single 503 response meaning there
1087 * were no successful RCPT TOs, or (b) a variable number of
1088 * responses, one for each successful RCPT TO. We need to send
1089 * bouncemail on each failed response and then return TRUE anyway,
1090 * otherwise the message will get left in the queue and resent
1091 * to people who got it the first time.
1093 if (ctl->listener == LMTP_MODE)
1095 if (lmtp_responses == 0)
1097 SMTP_ok(ctl->smtp_socket);
1100 * According to RFC2033, 503 is the only legal response
1101 * if no RCPT TO commands succeeded. No error recovery
1102 * is really possible here, as we have no idea what
1103 * insane thing the listener might be doing if it doesn't
1106 if (atoi(smtp_response) == 503)
1107 report(stderr, GT_("LMTP delivery error on EOM\n"));
1110 GT_("Unexpected non-503 response to LMTP EOM: %s\n"),
1114 * It's not completely clear what to do here. We choose to
1115 * interpret delivery failure here as a transient error,
1116 * the same way SMTP delivery failure is handled. If we're
1117 * wrong, an undead message will get stuck in the queue.
1126 /* eat the RFC2033-required responses, saving errors */
1127 xalloca(responses, char **, sizeof(char *) * lmtp_responses);
1128 for (errors = i = 0; i < lmtp_responses; i++)
1130 if (SMTP_ok(ctl->smtp_socket) == SM_OK)
1131 responses[i] = (char *)NULL;
1134 xalloca(responses[errors],
1136 strlen(smtp_response)+1);
1137 strcpy(responses[errors], smtp_response);
1143 return(TRUE); /* all deliveries succeeded */
1146 * One or more deliveries failed.
1147 * If we can bounce a failures list back to the
1148 * sender, and the postmaster does not want to
1149 * deal with the bounces return TRUE, deleting the
1150 * message from the server so it won't be
1151 * re-forwarded on subsequent poll cycles.
1153 return(send_bouncemail(ctl, msg, XMIT_ACCEPT,
1154 "LSMTP partial delivery failure.\r\n",
1155 errors, responses));
1163 int open_warning_by_mail(struct query *ctl, struct msgblk *msg)
1164 /* set up output sink for a mailed warning to calling user */
1169 * Dispatching warning email is a little complicated. The problem is
1170 * that we have to deal with three distinct cases:
1172 * 1. Single-drop running from user account. Warning mail should
1173 * go to the local name for which we're collecting (coincides
1174 * with calling user).
1176 * 2. Single-drop running from root or other privileged ID, with rc
1177 * file generated on the fly (Ken Estes's weird setup...) Mail
1178 * should go to the local name for which we're collecting (does not
1179 * coincide with calling user).
1181 * 3. Multidrop. Mail must go to postmaster. We leave the recipients
1182 * member null so this message will fall through to run.postmaster.
1184 * The zero in the reallen element means we won't pass a SIZE
1185 * option to ESMTP; the message length would be more trouble than
1186 * it's worth to compute.
1188 struct msgblk reply = {NULL, NULL, "FETCHMAIL-DAEMON@", 0};
1191 strcat(reply.return_path, fetchmailhost);
1193 if (!MULTIDROP(ctl)) /* send to calling user */
1195 save_str(&reply.recipients, ctl->localnames->id, XMIT_ACCEPT);
1196 status = open_sink(ctl, &reply, &good, &bad);
1197 free_str_list(&reply.recipients);
1199 else /* send to postmaster */
1200 status = open_sink(ctl, &reply, &good, &bad);
1201 stuff_warning(ctl, "Date: %s", rfc822timestamp());
1205 #if defined(HAVE_STDARG_H)
1206 void stuff_warning(struct query *ctl, const char *fmt, ... )
1208 void stuff_warning(struct query *ctl, fmt, va_alist)
1210 const char *fmt; /* printf-style format */
1213 /* format and ship a warning message line by mail */
1215 char buf[POPBUFSIZE];
1219 * stuffline() requires its input to be writeable (for CR stripping),
1220 * so we needed to copy the message to a writeable buffer anyway in
1221 * case it was a string constant. We make a virtue of that necessity
1222 * here by supporting stdargs/varargs.
1224 #if defined(HAVE_STDARG_H)
1229 #ifdef HAVE_VSNPRINTF
1230 vsnprintf(buf, sizeof(buf), fmt, ap);
1232 vsprintf(buf, fmt, ap);
1236 #ifdef HAVE_SNPRINTF
1237 snprintf(buf+strlen(buf), sizeof(buf)-strlen(buf), "\r\n");
1239 strcat(buf, "\r\n");
1240 #endif /* HAVE_SNPRINTF */
1242 stuffline(ctl, buf);
1245 void close_warning_by_mail(struct query *ctl, struct msgblk *msg)
1246 /* sign and send mailed warnings */
1248 stuff_warning(ctl, GT_("--\r\n\t\t\t\tThe Fetchmail Daemon\r\n"));
1249 close_sink(ctl, msg, TRUE);
1252 /* sink.c ends here */