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.
20 #endif /* HAVE_MEMORY_H */
21 #if defined(STDC_HEADERS)
24 #if defined(HAVE_UNISTD_H)
27 #if defined(HAVE_STDARG_H)
35 #include "fetchmail.h"
37 /* for W* macros after pclose() */
39 #include <sys/types.h>
40 #include <sys/resource.h>
47 /* BSD portability hack...I know, this is an ugly place to put it */
48 #if !defined(SIGCHLD) && defined(SIGCLD)
49 #define SIGCHLD SIGCLD
52 /* makes the open_sink()/close_sink() pair non-reentrant */
53 static int lmtp_responses;
55 void smtp_close(struct query *ctl, int sayquit)
56 /* close the socket to SMTP server */
58 if (ctl->smtp_socket != -1)
61 SMTP_quit(ctl->smtp_socket, ctl->smtphostmode);
62 SockClose(ctl->smtp_socket);
63 ctl->smtp_socket = -1;
68 int smtp_open(struct query *ctl)
69 /* try to open a socket to the appropriate SMTP server for this query */
71 /* maybe it's time to close the socket in order to force delivery */
72 if (last_smtp_ok > 0 && time((time_t *)NULL) - last_smtp_ok > mytimeout)
77 if (NUM_NONZERO(ctl->batchlimit)) {
78 if (batchcount == ctl->batchlimit)
83 /* if no socket to any SMTP host is already set up, try to open one */
84 if (ctl->smtp_socket == -1)
87 * RFC 1123 requires that the domain name in HELO address is a
88 * "valid principal domain name" for the client host. If we're
89 * running in invisible mode, violate this with malice
90 * aforethought in order to make the Received headers and
93 * In fact this code relies on the RFC1123 requirement that the
94 * SMTP listener must accept messages even if verification of the
95 * HELO name fails (RFC1123 section 5.2.5, paragraph 2).
97 * How we compute the true mailhost name to pass to the
98 * listener doesn't affect behavior on RFC1123-violating
99 * listeners that check for name match; we're going to lose
100 * on those anyway because we can never give them a name
101 * that matches the local machine fetchmail is running on.
102 * What it will affect is the listener's logging.
105 const char *id_me = run.invisible ? ctl->server.truename : fetchmailhost;
106 int oldphase = phase;
107 char *parsed_host = NULL;
112 * Run down the SMTP hunt list looking for a server that's up.
113 * Use both explicit hunt entries (value TRUE) and implicit
114 * (default) ones (value FALSE).
117 phase = LISTENER_WAIT;
119 set_timeout(ctl->server.timeout);
120 for (idp = ctl->smtphunt; idp; idp = idp->next)
123 char *portnum = SMTP_PORT;
125 ctl->smtphost = idp->id; /* remember last host tried. */
126 if (ctl->smtphost[0]=='/')
128 ctl->smtphostmode = LMTP_MODE;
130 if ((ctl->smtp_socket = UnixOpen(ctl->smtphost))==-1)
135 ctl->smtphostmode = ctl->listener;
136 parsed_host = xstrdup(idp->id);
137 if ((cp = strrchr(parsed_host, '/')))
143 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,
144 ctl->server.plugout, &ai1)) == -1)
151 /* return immediately for ODMR */
152 if (ctl->server.protocol == P_ODMR)
157 return(ctl->smtp_socket); /* success */
160 /* first, probe for ESMTP */
161 if (SMTP_ok(ctl->smtp_socket, ctl->smtphostmode) == SM_OK &&
162 SMTP_ehlo(ctl->smtp_socket, ctl->smtphostmode, id_me,
163 ctl->server.esmtp_name, ctl->server.esmtp_password,
164 &ctl->server.esmtp_options) == SM_OK)
168 * RFC 1869 warns that some listeners hang up on a failed EHLO,
169 * so it's safest not to assume the socket will still be good.
173 /* if opening for ESMTP failed, try SMTP */
174 if (ctl->smtphost[0]=='/')
176 if ((ctl->smtp_socket = UnixOpen(ctl->smtphost))==-1)
181 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,
182 ctl->server.plugout, &ai1)) == -1)
189 if (SMTP_ok(ctl->smtp_socket, ctl->smtphostmode) == SM_OK &&
190 SMTP_helo(ctl->smtp_socket, ctl->smtphostmode, id_me) == SM_OK)
199 * RFC 1123 requires that the domain name part of the
200 * RCPT TO address be "canonicalized", that is a FQDN
201 * or MX but not a CNAME. Some listeners (like exim)
202 * enforce this. Now that we have the actual hostname,
203 * compute what we should canonicalize with.
205 xfree(ctl->destaddr);
206 if (ctl->smtpaddress)
207 ctl->destaddr = xstrdup(ctl->smtpaddress);
208 /* parsed_host is smtphost without the /port */
209 else if (parsed_host && parsed_host[0] != 0)
210 ctl->destaddr = xstrdup(parsed_host);
211 /* No smtphost is specified or it is a UNIX socket, then use
212 localhost as a domain part. */
214 ctl->destaddr = xstrdup("localhost");
217 /* end if (ctl->smtp_socket == -1) */
219 if (outlevel >= O_DEBUG && ctl->smtp_socket != -1)
220 report(stdout, GT_("forwarding to %s\n"), ctl->smtphost);
222 return(ctl->smtp_socket);
225 static void sanitize(char *s)
230 for (cp = s; (cp = strchr (cp, '\'')); cp++)
234 char *rcpt_address(struct query *ctl, const char *id,
237 static char addr[HOSTLEN+USERNAMELEN+1];
240 snprintf(addr, sizeof (addr), "%s", id);
242 else if (usesmtpname && ctl->smtpname)
244 snprintf(addr, sizeof (addr), "%s", ctl->smtpname);
248 snprintf(addr, sizeof (addr), "%s@%s", id, ctl->destaddr);
253 static int send_bouncemail(struct query *ctl, struct msgblk *msg,
254 int userclass, char *message /* should have \r\n at the end */,
255 int nerrors, char *errors[])
256 /* bounce back an error report a la RFC 1892 */
258 char daemon_name[15 + HOSTLEN] = "MAILER-DAEMON@";
259 char boundary[BUFSIZ], *bounce_to;
261 static char *fqdn_of_host = NULL;
262 const char *md1 = "MAILER-DAEMON", *md2 = "MAILER-DAEMON@";
264 /* don't bounce in reply to undeliverable bounces */
265 if (!msg || !msg->return_path[0] ||
266 strcmp(msg->return_path, "<>") == 0 ||
267 strcasecmp(msg->return_path, md1) == 0 ||
268 strncasecmp(msg->return_path, md2, strlen(md2)) == 0)
271 bounce_to = (run.bouncemail ? msg->return_path : run.postmaster);
273 /* can't just use fetchmailhost here, it might be localhost */
274 if (fqdn_of_host == NULL)
275 fqdn_of_host = host_fqdn(0); /* can't afford to bail out and
277 strlcat(daemon_name, fqdn_of_host, sizeof(daemon_name));
279 /* we need only SMTP for this purpose */
280 /* XXX FIXME: hardcoding localhost is nonsense if smtphost can be
282 if ((sock = SockOpen("localhost", SMTP_PORT, NULL, &ai1)) == -1)
285 if (SMTP_ok(sock, SMTP_MODE) != SM_OK)
291 if (SMTP_helo(sock, SMTP_MODE, fetchmailhost) != SM_OK
292 || SMTP_from(sock, SMTP_MODE, "<>", (char *)NULL) != SM_OK
293 || SMTP_rcpt(sock, SMTP_MODE, bounce_to) != SM_OK
294 || SMTP_data(sock, SMTP_MODE) != SM_OK)
296 SMTP_quit(sock, SMTP_MODE);
301 /* our first duty is to keep the sacred foo counters turning... */
302 snprintf(boundary, sizeof(boundary), "foo-mani-padme-hum-%ld-%ld-%ld",
303 (long)getpid(), (long)getppid(), (long)time(NULL));
305 if (outlevel >= O_VERBOSE)
306 report(stdout, GT_("SMTP: (bounce-message body)\n"));
308 /* this will usually go to sylog... */
309 report(stderr, GT_("mail from %s bounced to %s\n"),
310 daemon_name, bounce_to);
313 /* bouncemail headers */
314 SockPrintf(sock, "Subject: Mail delivery failed: returning message to sender\r\n");
315 SockPrintf(sock, "From: Mail Delivery System <%s>\r\n", daemon_name);
316 SockPrintf(sock, "To: %s\r\n", bounce_to);
317 SockPrintf(sock, "MIME-Version: 1.0\r\n");
318 SockPrintf(sock, "Content-Type: multipart/report; report-type=delivery-status;\r\n\tboundary=\"%s\"\r\n", boundary);
319 SockPrintf(sock, "\r\n");
321 /* RFC1892 part 1 -- human-readable message */
322 SockPrintf(sock, "--%s\r\n", boundary);
323 SockPrintf(sock,"Content-Type: text/plain\r\n");
324 SockPrintf(sock, "\r\n");
325 SockPrintf(sock, "This message was created automatically by mail delivery software.\r\n");
326 SockPrintf(sock, "\r\n");
327 SockPrintf(sock, "A message that you sent could not be delivered to one or more of its\r\n");
328 SockPrintf(sock, "recipients. This is a permanent error.\r\n");
329 SockPrintf(sock, "\r\n");
330 SockPrintf(sock, "Reason: %s", message);
331 SockPrintf(sock, "\r\n");
332 SockPrintf(sock, "The following address(es) failed:\r\n");
340 for (idp = msg->recipients; idp; idp = idp->next)
342 if (idp->val.status.mark == userclass)
345 SockPrintf(sock, "%s\r\n", rcpt_address (ctl, idp->id, 1));
347 if (nerrors == 1) error = errors[0];
348 else if (nerrors <= nusers)
350 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
353 else error = errors[nusers++];
355 SockPrintf(sock, " SMTP error: %s\r\n\r\n", error);
359 /* RFC1892 part 2 -- machine-readable responses */
360 SockPrintf(sock, "--%s\r\n", boundary);
361 SockPrintf(sock,"Content-Type: message/delivery-status\r\n");
362 SockPrintf(sock, "\r\n");
363 SockPrintf(sock, "Reporting-MTA: dns; %s\r\n", fqdn_of_host);
366 for (idp = msg->recipients; idp; idp = idp->next)
367 if (idp->val.status.mark == userclass)
370 /* Minimum RFC1894 compliance + Diagnostic-Code field */
371 SockPrintf(sock, "\r\n");
372 SockPrintf(sock, "Final-Recipient: rfc822; %s\r\n",
373 rcpt_address (ctl, idp->id, 1));
374 SockPrintf(sock, "Last-Attempt-Date: %s\r\n", rfc822timestamp());
375 SockPrintf(sock, "Action: failed\r\n");
378 /* one error applies to all users */
380 else if (nerrors <= nusers)
382 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
386 /* errors correspond 1-1 to selected users */
387 error = errors[nusers++];
389 if (strlen(error) > 9 && isdigit((unsigned char)error[4])
390 && error[5] == '.' && isdigit((unsigned char)error[6])
391 && error[7] == '.' && isdigit((unsigned char)error[8]))
392 /* Enhanced status code available, use it */
393 SockPrintf(sock, "Status: %5.5s\r\n", &(error[4]));
395 /* Enhanced status code not available, fake one */
396 SockPrintf(sock, "Status: %c.0.0\r\n", error[0]);
397 SockPrintf(sock, "Diagnostic-Code: %s\r\n", error);
399 SockPrintf(sock, "\r\n");
402 /* RFC1892 part 3 -- headers of undelivered message */
403 SockPrintf(sock, "--%s\r\n", boundary);
404 SockPrintf(sock, "Content-Type: text/rfc822-headers\r\n");
405 SockPrintf(sock, "\r\n");
408 SockWrite(sock, msg->headers, strlen(msg->headers));
409 SockPrintf(sock, "\r\n");
411 SockPrintf(sock, "--%s--\r\n", boundary);
413 if (SMTP_eom(sock, SMTP_MODE) != SM_OK
414 || SMTP_quit(sock, SMTP_MODE) != SM_OK)
425 static int handle_smtp_report(struct query *ctl, struct msgblk *msg)
426 /* handle SMTP errors based on the content of SMTP_response */
427 /* returns either PS_REFUSED (to delete message from the server),
428 * or PS_TRANSIENT (keeps the message on the server) */
430 int smtperr = atoi(smtp_response);
435 responses[0] = xstrdup(smtp_response);
439 * Don't do this! It can really mess you up if, for example, you're
440 * reporting an error with a single RCPT TO address among several;
441 * RSET discards the message body and it doesn't get sent to the
444 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
445 if (outlevel >= O_DEBUG)
446 report(stdout, GT_("Saved error is still %d\n"), smtperr);
447 #endif /* __UNUSED */
450 * Note: send_bouncemail message strings are not made subject
451 * to gettext translation because (a) they're going to be
452 * embedded in a text/plain 7bit part, and (b) they're
453 * going to be associated with listener error-response
454 * messages, which are probably in English (none of the
455 * MTAs I know about are internationalized).
457 for( walk = ctl->antispam; walk; walk = walk->next )
458 if ( walk->val.status.num == smtperr )
464 /* if (str_find(&ctl->antispam, smtperr)) */
468 * SMTP listener explicitly refuses to deliver mail
469 * coming from this address, probably due to an
470 * anti-spam domain exclusion. Respect this. Don't
471 * try to ship the message, and don't prevent it from
472 * being deleted. There's no point in bouncing the
473 * email either since most spammers don't put their
474 * real return email address anywhere in the headers
475 * (unless the user insists with the SET SPAMBOUNCE
480 * 571 = sendmail's "unsolicited email refused"
481 * 550 = exim's new antispam response (temporary)
482 * 501 = exim's old antispam response
483 * 554 = Postfix antispam response.
489 snprintf(rejmsg, sizeof(rejmsg),
490 "spam filter or virus scanner rejected message because:\r\n"
491 "%s\r\n", responses[0]);
493 send_bouncemail(ctl, msg, XMIT_ACCEPT,
494 rejmsg, 1, responses);
501 * Suppress error message only if the response specifically
502 * meant `excluded for policy reasons'. We *should* see
503 * an error when the return code is less specific.
506 report(stderr, GT_("%cMTP error: %s\n"),
512 case 552: /* message exceeds fixed maximum message size */
514 * Permanent no-go condition on the
515 * ESMTP server. Don't try to ship the message,
516 * and allow it to be deleted.
519 send_bouncemail(ctl, msg, XMIT_ACCEPT,
520 "This message was too large (SMTP error 552).\r\n",
525 case 553: /* invalid sending domain */
527 * These latter days 553 usually means a spammer is trying to
528 * cover his tracks. We never bouncemail on these, because
529 * (a) the return address is invalid by definition, and
530 * (b) we wouldn't want spammers to get confirmation that
531 * this address is live, anyway.
533 #ifdef __DONT_FEED_THE_SPAMMERS__
535 send_bouncemail(ctl, msg, XMIT_ACCEPT,
536 "Invalid address in MAIL FROM (SMTP error 553).\r\n",
538 #endif /* __DONT_FEED_THE_SPAMMERS__ */
543 /* bounce non-transient errors back to the sender */
544 if (smtperr >= 500 && smtperr <= 599)
547 send_bouncemail(ctl, msg, XMIT_ACCEPT,
548 "General SMTP/ESMTP error.\r\n",
554 * We're going to end up here on 4xx errors, like:
556 * 451: temporarily unable to identify sender (exim)
557 * 452: temporary out-of-queue-space condition on the ESMTP server.
559 * These are temporary errors. Don't try to ship the message,
560 * and suppress deletion so it can be retried on a future
563 * Bouncemail *might* be appropriate here as a delay
564 * notification (note; if we ever add this, we must make
565 * sure the RFC1894 Action field is "delayed" rather than
566 * "failed"). But it's not really necessary because
567 * these are not actual failures, we're very likely to be
568 * able to recover on the next cycle.
571 return(PS_TRANSIENT);
575 static int handle_smtp_report_without_bounce(struct query *ctl, struct msgblk *msg)
576 /* handle SMTP errors based on the content of SMTP_response */
577 /* atleast one PS_TRANSIENT: do not send the bounce mail, keep the mail;
578 * no PS_TRANSIENT, atleast one PS_SUCCESS: send the bounce mail, delete the mail;
579 * no PS_TRANSIENT, no PS_SUCCESS: do not send the bounce mail, delete the mail */
581 int smtperr = atoi(smtp_response);
583 if (str_find(&ctl->antispam, smtperr))
591 report(stderr, GT_("%cMTP error: %s\n"),
597 case 552: /* message exceeds fixed maximum message size */
602 case 553: /* invalid sending domain */
603 #ifdef __DONT_FEED_THE_SPAMMERS__
606 #endif /* __DONT_FEED_THE_SPAMMERS__ */
610 /* bounce non-transient errors back to the sender */
611 if (smtperr >= 500 && smtperr <= 599)
613 return(PS_TRANSIENT);
617 /* these are shared by open_sink and stuffline */
620 int stuffline(struct query *ctl, char *buf)
621 /* ship a line to the given control block's output sink (SMTP server or MDA) */
626 /* The line may contain NUL characters. Find the last char to use
627 * -- the real line termination is the sequence "\n\0".
629 last = buf + 1; /* last[-1] must be valid! */
630 while ((last += strlen(last)) && (last[-1] != '\n'))
633 /* fix message lines that have only \n termination (for qmail) */
636 if (last - 1 == buf || last[-2] != '\r')
645 phase = FORWARDING_WAIT;
648 * SMTP byte-stuffing. We only do this if the protocol does *not*
649 * use .<CR><LF> as EOM. If it does, the server will already have
650 * decorated any . lines it sends back up.
654 if (ctl->server.base_protocol->delimited) /* server has already byte-stuffed */
657 /* writing to MDA, undo byte-stuffing */
660 /* writing to SMTP, leave the byte-stuffing in place */;
663 else /* if (!protocol->delimited) -- not byte-stuffed already */
668 n = SockWrite(ctl->smtp_socket, buf, 1);
670 n = fwrite(buf, 1, 1, sinkfp);
671 if (ferror(sinkfp)) n = -1;
679 /* we may need to strip carriage returns */
684 for (sp = tp = buf; sp < last; sp++)
692 if (ctl->mda || ctl->bsmtp) {
693 n = fwrite(buf, 1, last - buf, sinkfp);
694 if (ferror(sinkfp)) n = -1;
695 } else if (ctl->smtp_socket != -1)
696 n = SockWrite(ctl->smtp_socket, buf, last - buf);
703 static int open_bsmtp_sink(struct query *ctl, struct msgblk *msg,
704 int *good_addresses, int *bad_addresses)
705 /* open a BSMTP stream */
710 if (strcmp(ctl->bsmtp, "-") == 0)
713 sinkfp = fopen(ctl->bsmtp, "a");
715 if (!sinkfp || ferror(sinkfp)) {
716 report(stderr, GT_("BSMTP file open failed: %s\n"),
721 /* see the ap computation under the SMTP branch */
722 need_anglebrs = (msg->return_path[0] != '<');
725 need_anglebrs ? "<" : "",
726 (msg->return_path[0]) ? msg->return_path : user,
727 need_anglebrs ? ">" : "");
729 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
730 fputs(" BODY=8BITMIME", sinkfp);
731 else if (ctl->mimemsg & MSG_IS_7BIT)
732 fputs(" BODY=7BIT", sinkfp);
734 /* exim's BSMTP processor does not handle SIZE */
735 /* fprintf(sinkfp, " SIZE=%d", msg->reallen); */
737 fprintf(sinkfp, "\r\n");
740 * RFC 1123 requires that the domain name part of the
741 * RCPT TO address be "canonicalized", that is a FQDN
742 * or MX but not a CNAME. Some listeners (like exim)
743 * enforce this. Now that we have the actual hostname,
744 * compute what we should canonicalize with.
746 xfree(ctl->destaddr);
747 ctl->destaddr = xstrdup(ctl->smtpaddress ? ctl->smtpaddress : "localhost");
750 for (idp = msg->recipients; idp; idp = idp->next)
751 if (idp->val.status.mark == XMIT_ACCEPT)
753 fprintf(sinkfp, "RCPT TO:<%s>\r\n",
754 rcpt_address (ctl, idp->id, 1));
758 fputs("DATA\r\n", sinkfp);
760 if (fflush(sinkfp) || ferror(sinkfp))
762 report(stderr, GT_("BSMTP preamble write failed.\n"));
769 /* this is experimental and will be removed if double bounces are reported */
770 #define EXPLICIT_BOUNCE_ON_BAD_ADDRESS
773 static const char *is_quad(const char *q)
774 /* Check if the string passed in points to what could be one quad of a
775 * dotted-quad IP address. Requirements are that the string is not a
776 * NULL pointer, begins with a period (which is skipped) or a digit
777 * and ends with a period or a NULL. If these requirements are met, a
778 * pointer to the last character (the period or the NULL character) is
779 * returned; otherwise NULL.
788 for(r=q;isdigit((unsigned char)*r);r++)
790 if ( ((*r) && (*r != '.')) || ((r-q) < 1) || ((r-q)>3) )
792 /* Make sure quad is < 255 */
801 else if (*(q+1) == '5')
811 static int is_dottedquad(const char *hostname)
812 /* Returns a true value if the passed in string looks like an IP
813 * address in dotted-quad form, and a false value otherwise.
817 return ((hostname=is_quad(is_quad(is_quad(is_quad(hostname))))) != NULL) &&
821 static int open_smtp_sink(struct query *ctl, struct msgblk *msg,
822 int *good_addresses, int *bad_addresses /* this must be signed, to prevent endless loop in from_addresses */)
823 /* open an SMTP stream */
827 char options[MSGBUFSIZE];
828 char addr[HOSTLEN+USERNAMELEN+1];
829 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
830 char **from_responses;
831 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
833 int force_transient_error = 0;
837 * Compute ESMTP options.
840 if (ctl->server.esmtp_options & ESMTP_8BITMIME) {
841 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
842 strcpy(options, " BODY=8BITMIME");
843 else if (ctl->mimemsg & MSG_IS_7BIT)
844 strcpy(options, " BODY=7BIT");
847 if ((ctl->server.esmtp_options & ESMTP_SIZE) && msg->reallen > 0)
848 sprintf(options + strlen(options), " SIZE=%d", msg->reallen);
851 * Try to get the SMTP listener to take the Return-Path
852 * address as MAIL FROM. If it won't, fall back on the
853 * remotename and mailserver host. This won't affect replies,
854 * which use the header From address anyway; the MAIL FROM
855 * address is a place for the SMTP listener to send
856 * bouncemail. The point is to guarantee a FQDN in the MAIL
857 * FROM line -- some SMTP listeners, like smail, become
860 * RFC 1123 requires that the domain name part of the
861 * MAIL FROM address be "canonicalized", that is a
862 * FQDN or MX but not a CNAME. We'll assume the Return-Path
863 * header is already in this form here (it certainly
864 * is if rewrite is on). RFC 1123 is silent on whether
865 * a nonexistent hostname part is considered canonical.
867 * This is a potential problem if the MTAs further upstream
868 * didn't pass canonicalized From/Return-Path lines, *and* the
869 * local SMTP listener insists on them.
871 * Handle the case where an upstream MTA is setting a return
872 * path equal to "@". Ghod knows why anyone does this, but
873 * it's been reported to happen in mail from Amazon.com and
876 * Also, if the hostname is a dotted quad, wrap it in square brackets.
877 * Apparently this is required by RFC2821, section 4.1.3.
879 if (!msg->return_path[0] || (msg->return_path[0] == '@'))
881 if (strchr(ctl->remotename,'@') || strchr(ctl->remotename,'!'))
883 snprintf(addr, sizeof(addr), "%s", ctl->remotename);
885 else if (is_dottedquad(ctl->server.truename))
887 snprintf(addr, sizeof(addr), "%s@[%s]", ctl->remotename,
888 ctl->server.truename);
892 snprintf(addr, sizeof(addr),
893 "%s@%s", ctl->remotename, ctl->server.truename);
897 else if (strchr(msg->return_path,'@') || strchr(msg->return_path,'!'))
898 ap = msg->return_path;
899 /* in case Return-Path was "<>" we want to preserve that */
900 else if (strcmp(msg->return_path,"<>") == 0)
901 ap = msg->return_path;
902 else /* in case Return-Path existed but was local */
904 if (is_dottedquad(ctl->server.truename))
906 snprintf(addr, sizeof(addr), "%s@[%s]", msg->return_path,
907 ctl->server.truename);
911 snprintf(addr, sizeof(addr), "%s@%s",
912 msg->return_path, ctl->server.truename);
917 if ((smtp_err = SMTP_from(ctl->smtp_socket, ctl->smtphostmode,
918 ap, options)) == SM_UNRECOVERABLE)
921 return(PS_TRANSIENT);
923 if (smtp_err != SM_OK)
925 int err = handle_smtp_report(ctl, msg); /* map to PS_TRANSIENT or PS_REFUSED */
927 SMTP_rset(ctl->smtp_socket, ctl->smtphostmode); /* stay on the safe side */
932 * Now list the recipient addressees
935 for (idp = msg->recipients; idp; idp = idp->next)
937 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
938 from_responses = (char **)xmalloc(sizeof(char *) * total_addresses);
939 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
940 for (idp = msg->recipients; idp; idp = idp->next)
941 if (idp->val.status.mark == XMIT_ACCEPT)
944 address = rcpt_address (ctl, idp->id, 1);
945 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket, ctl->smtphostmode,
946 address)) == SM_UNRECOVERABLE)
950 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
951 while (*bad_addresses)
952 free(from_responses[--*bad_addresses]);
953 free(from_responses);
954 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
955 return(PS_TRANSIENT);
957 if (smtp_err == SM_OK)
961 switch (handle_smtp_report_without_bounce(ctl, msg))
964 force_transient_error = 1;
968 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
969 from_responses[*bad_addresses] = xstrdup(smtp_response);
970 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
973 idp->val.status.mark = XMIT_RCPTBAD;
974 if (outlevel >= O_VERBOSE)
976 GT_("%cMTP listener doesn't like recipient address `%s'\n"),
977 ctl->smtphostmode, address);
981 if (outlevel >= O_VERBOSE)
983 GT_("%cMTP listener doesn't really like recipient address `%s'\n"),
984 ctl->smtphostmode, address);
990 if (force_transient_error) {
991 /* do not risk dataloss due to overengineered multidrop
992 * crap. If one of the recipients returned PS_TRANSIENT,
993 * we return exactly that.
995 SMTP_rset(ctl->smtp_socket, ctl->smtphostmode); /* required by RFC1870 */
998 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
1000 * This should not be necessary, because the SMTP listener itself
1001 * should generate a bounce for the bad address.
1003 * XXX FIXME 2006-01-19: is this comment true? I don't think
1004 * it is, because the SMTP listener isn't required to accept bogus
1005 * messages. There appears to be general SMTP<->MDA and
1006 * responsibility confusion.
1009 send_bouncemail(ctl, msg, XMIT_RCPTBAD,
1010 "Some addresses were rejected by the MDA fetchmail forwards to.\r\n",
1011 *bad_addresses, from_responses);
1012 while (*bad_addresses)
1013 free(from_responses[--*bad_addresses]);
1014 free(from_responses);
1015 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
1018 * It's tempting to do local notification only if bouncemail was
1019 * insufficient -- that is, to add && total_addresses > *bad_addresses
1020 * to the test here. The problem with this theory is that it would
1021 * make initial diagnosis of a broken multidrop configuration very
1022 * hard -- most single-recipient messages would just invisibly bounce.
1024 if (!(*good_addresses))
1026 if (!run.postmaster[0])
1028 if (outlevel >= O_VERBOSE)
1029 report(stderr, GT_("no address matches; no postmaster set.\n"));
1030 SMTP_rset(ctl->smtp_socket, ctl->smtphostmode); /* required by RFC1870 */
1033 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket, ctl->smtphostmode,
1034 rcpt_address (ctl, run.postmaster, 0))) == SM_UNRECOVERABLE)
1037 return(PS_TRANSIENT);
1039 if (smtp_err != SM_OK)
1041 report(stderr, GT_("can't even send to %s!\n"), run.postmaster);
1042 SMTP_rset(ctl->smtp_socket, ctl->smtphostmode); /* required by RFC1870 */
1046 if (outlevel >= O_VERBOSE)
1047 report(stderr, GT_("no address matches; forwarding to %s.\n"), run.postmaster);
1051 * Tell the listener we're ready to send data.
1052 * Some listeners (like zmailer) may return antispam errors here.
1054 if ((smtp_err = SMTP_data(ctl->smtp_socket, ctl->smtphostmode))
1055 == SM_UNRECOVERABLE)
1058 return(PS_TRANSIENT);
1060 if (smtp_err != SM_OK)
1062 int err = handle_smtp_report(ctl, msg);
1063 SMTP_rset(ctl->smtp_socket, ctl->smtphostmode); /* stay on the safe side */
1068 * We need to stash this away in order to know how many
1069 * response lines to expect after the LMTP end-of-message.
1071 lmtp_responses = *good_addresses;
1076 static int open_mda_sink(struct query *ctl, struct msgblk *msg,
1077 int *good_addresses, int *bad_addresses)
1078 /* open a stream to a local MDA */
1082 #endif /* HAVE_SETEUID */
1084 int length = 0, fromlen = 0, nameslen = 0;
1085 char *names = NULL, *before, *after, *from = NULL;
1087 (void)bad_addresses;
1088 xfree(ctl->destaddr);
1089 ctl->destaddr = xstrdup("localhost");
1091 for (idp = msg->recipients; idp; idp = idp->next)
1092 if (idp->val.status.mark == XMIT_ACCEPT)
1093 (*good_addresses)++;
1095 length = strlen(ctl->mda);
1096 before = xstrdup(ctl->mda);
1098 /* get user addresses for %T (or %s for backward compatibility) */
1099 if (strstr(before, "%s") || strstr(before, "%T"))
1102 * We go through this in order to be able to handle very
1103 * long lists of users and (re)implement %s.
1106 for (idp = msg->recipients; idp; idp = idp->next)
1107 if ((idp->val.status.mark == XMIT_ACCEPT))
1108 nameslen += (strlen(idp->id) + 1); /* string + ' ' */
1109 if ((*good_addresses == 0))
1110 nameslen = strlen(run.postmaster);
1112 names = (char *)xmalloc(nameslen + 1); /* account for '\0' */
1113 if (*good_addresses == 0)
1114 strcpy(names, run.postmaster);
1118 for (idp = msg->recipients; idp; idp = idp->next)
1119 if (idp->val.status.mark == XMIT_ACCEPT)
1121 strcat(names, idp->id);
1124 names[--nameslen] = '\0'; /* chop trailing space */
1130 /* get From address for %F */
1131 if (strstr(before, "%F"))
1133 from = xstrdup(msg->return_path);
1137 fromlen = strlen(from);
1140 /* do we have to build an mda string? */
1145 /* find length of resulting mda string */
1147 while ((sp = strstr(sp, "%s"))) {
1148 length += nameslen; /* subtract %s and add '' */
1152 while ((sp = strstr(sp, "%T"))) {
1153 length += nameslen; /* subtract %T and add '' */
1157 while ((sp = strstr(sp, "%F"))) {
1158 length += fromlen; /* subtract %F and add '' */
1162 after = (char *)xmalloc(length + 1);
1164 /* copy mda source string to after, while expanding %[sTF] */
1165 for (dp = after, sp = before; (*dp = *sp); dp++, sp++) {
1166 if (sp[0] != '%') continue;
1168 /* need to expand? BTW, no here overflow, because in
1169 ** the worst case (end of string) sp[1] == '\0' */
1170 if (sp[1] == 's' || sp[1] == 'T') {
1175 sp++; /* position sp over [sT] */
1176 dp--; /* adjust dp */
1177 } else if (sp[1] == 'F') {
1182 sp++; /* position sp over F */
1183 dp--; /* adjust dp */
1202 if (outlevel >= O_DEBUG)
1203 report(stdout, GT_("about to deliver with: %s\n"), before);
1207 * Arrange to run with user's permissions if we're root.
1208 * This will initialize the ownership of any files the
1209 * MDA creates properly. (The seteuid call is available
1210 * under all BSDs and Linux)
1212 orig_uid = getuid();
1214 #endif /* HAVE_SETEUID */
1216 sinkfp = popen(before, "w");
1221 /* this will fail quietly if we didn't start as root */
1223 #endif /* HAVE_SETEUID */
1227 report(stderr, GT_("MDA open failed\n"));
1232 * We need to disable the normal SIGCHLD handling here because
1233 * sigchld_handler() would reap away the error status, returning
1234 * error status instead of 0 for successful completion.
1236 set_signal_handler(SIGCHLD, SIG_DFL);
1241 int open_sink(struct query *ctl, struct msgblk *msg,
1242 int *good_addresses, int *bad_addresses)
1243 /* set up sinkfp to be an input sink we can ship a message to */
1245 *bad_addresses = *good_addresses = 0;
1247 if (ctl->bsmtp) /* dump to a BSMTP batch file */
1248 return(open_bsmtp_sink(ctl, msg, good_addresses, bad_addresses));
1250 * Try to forward to an SMTP or LMTP listener. If the attempt to
1251 * open a socket fails, fall through to attempt delivery via
1254 else if (!ctl->mda && smtp_open(ctl) != -1)
1255 return(open_smtp_sink(ctl, msg, good_addresses, bad_addresses));
1258 * Awkward case. User didn't specify an MDA. Our attempt to get a
1259 * listener socket failed. Try to cope anyway -- initial configuration
1260 * may have found procmail.
1264 report(stderr, GT_("%cMTP connect to %s failed\n"),
1266 ctl->smtphost ? ctl->smtphost : "localhost");
1268 #ifndef FALLBACK_MDA
1269 /* No fallback MDA declared. Bail out. */
1273 * If user had things set up to forward offsite, no way
1274 * we want to deliver locally!
1276 if (ctl->smtphost && strcmp(ctl->smtphost, "localhost"))
1280 * User was delivering locally. We have a fallback MDA.
1281 * Latch it in place, logging the error, and fall through.
1282 * Set stripcr as we would if MDA had been the initial transport
1284 ctl->mda = FALLBACK_MDA;
1286 ctl->stripcr = TRUE;
1288 report(stderr, GT_("can't raise the listener; falling back to %s"),
1293 if (ctl->mda) /* must deliver through an MDA */
1294 return(open_mda_sink(ctl, msg, good_addresses, bad_addresses));
1299 void release_sink(struct query *ctl)
1300 /* release the per-message output sink, whether it's a pipe or SMTP socket */
1302 if (ctl->bsmtp && sinkfp)
1304 if (strcmp(ctl->bsmtp, "-"))
1307 sinkfp = (FILE *)NULL;
1315 sinkfp = (FILE *)NULL;
1317 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1321 int close_sink(struct query *ctl, struct msgblk *msg, flag forward)
1322 /* perform end-of-message actions on the current output sink */
1327 int rc = 0, e = 0, e2 = 0, err = 0;
1329 /* close the delivery pipe, we'll reopen before next message */
1333 err = 1, e2 = errno;
1334 if ((fflush(sinkfp)))
1335 err = 1, e2 = errno;
1338 rc = pclose(sinkfp);
1340 sinkfp = (FILE *)NULL;
1345 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1350 report(stderr, GT_("Error writing to MDA: %s\n"), strerror(e2));
1351 } else if (WIFSIGNALED(rc)) {
1353 GT_("MDA died of signal %d\n"), WTERMSIG(rc));
1354 } else if (WIFEXITED(rc)) {
1356 GT_("MDA returned nonzero status %d\n"), WEXITSTATUS(rc));
1359 GT_("Strange: MDA pclose returned %d and errno %d/%s, cannot handle at %s:%d\n"),
1360 rc, e, strerror(e), __FILE__, __LINE__);
1366 else if (ctl->bsmtp && sinkfp)
1370 /* implicit disk-full check here... */
1371 fputs(".\r\n", sinkfp);
1372 error = ferror(sinkfp);
1373 if (strcmp(ctl->bsmtp, "-"))
1375 if (fclose(sinkfp) == EOF) error = 1;
1376 sinkfp = (FILE *)NULL;
1381 GT_("Message termination or close of BSMTP file failed\n"));
1387 /* write message terminator */
1388 if ((smtp_err = SMTP_eom(ctl->smtp_socket, ctl->smtphostmode))
1389 == SM_UNRECOVERABLE)
1394 if (smtp_err != SM_OK)
1396 if (handle_smtp_report(ctl, msg) != PS_REFUSED)
1398 SMTP_rset(ctl->smtp_socket, ctl->smtphostmode); /* stay on the safe side */
1403 report(stderr, GT_("SMTP listener refused delivery\n"));
1404 SMTP_rset(ctl->smtp_socket, ctl->smtphostmode); /* stay on the safe side */
1410 * If this is an SMTP connection, SMTP_eom() ate the response.
1411 * But could be this is an LMTP connection, in which case we have to
1412 * interpret either (a) a single 503 response meaning there
1413 * were no successful RCPT TOs, or (b) a variable number of
1414 * responses, one for each successful RCPT TO. We need to send
1415 * bouncemail on each failed response and then return TRUE anyway,
1416 * otherwise the message will get left in the queue and resent
1417 * to people who got it the first time.
1419 if (ctl->smtphostmode == LMTP_MODE)
1421 if (lmtp_responses == 0)
1423 SMTP_ok(ctl->smtp_socket, ctl->smtphostmode);
1426 * According to RFC2033, 503 is the only legal response
1427 * if no RCPT TO commands succeeded. No error recovery
1428 * is really possible here, as we have no idea what
1429 * insane thing the listener might be doing if it doesn't
1432 if (atoi(smtp_response) == 503)
1433 report(stderr, GT_("LMTP delivery error on EOM\n"));
1436 GT_("Unexpected non-503 response to LMTP EOM: %s\n"),
1440 * It's not completely clear what to do here. We choose to
1441 * interpret delivery failure here as a transient error,
1442 * the same way SMTP delivery failure is handled. If we're
1443 * wrong, an undead message will get stuck in the queue.
1449 int i, errors, rc = FALSE;
1452 /* eat the RFC2033-required responses, saving errors */
1453 responses = (char **)xmalloc(sizeof(char *) * lmtp_responses);
1454 for (errors = i = 0; i < lmtp_responses; i++)
1456 if ((smtp_err = SMTP_ok(ctl->smtp_socket, ctl->smtphostmode))
1457 == SM_UNRECOVERABLE)
1462 if (smtp_err != SM_OK)
1464 responses[errors] = xstrdup(smtp_response);
1470 rc = TRUE; /* all deliveries succeeded */
1473 * One or more deliveries failed.
1474 * If we can bounce a failures list back to the
1475 * sender, and the postmaster does not want to
1476 * deal with the bounces return TRUE, deleting the
1477 * message from the server so it won't be
1478 * re-forwarded on subsequent poll cycles.
1480 rc = send_bouncemail(ctl, msg, XMIT_ACCEPT,
1481 "LMTP partial delivery failure.\r\n",
1485 for (i = 0; i < errors; i++)
1496 int open_warning_by_mail(struct query *ctl)
1497 /* set up output sink for a mailed warning to calling user */
1502 * Dispatching warning email is a little complicated. The problem is
1503 * that we have to deal with three distinct cases:
1505 * 1. Single-drop running from user account. Warning mail should
1506 * go to the local name for which we're collecting (coincides
1507 * with calling user).
1509 * 2. Single-drop running from root or other privileged ID, with rc
1510 * file generated on the fly (Ken Estes's weird setup...) Mail
1511 * should go to the local name for which we're collecting (does not
1512 * coincide with calling user).
1514 * 3. Multidrop. Mail must go to postmaster. We leave the recipients
1515 * member null so this message will fall through to run.postmaster.
1517 * The zero in the reallen element means we won't pass a SIZE
1518 * option to ESMTP; the message length would be more trouble than
1519 * it's worth to compute.
1521 struct msgblk reply = {NULL, NULL, "FETCHMAIL-DAEMON@", 0, 0};
1524 strlcat(reply.return_path, ctl->smtpaddress ? ctl->smtpaddress :
1525 fetchmailhost, sizeof(reply.return_path));
1527 if (!MULTIDROP(ctl)) /* send to calling user */
1529 save_str(&reply.recipients, ctl->localnames->id, XMIT_ACCEPT);
1530 status = open_sink(ctl, &reply, &good, &bad);
1531 free_str_list(&reply.recipients);
1533 else /* send to postmaster */
1534 status = open_sink(ctl, &reply, &good, &bad);
1536 stuff_warning(NULL, ctl, "From: FETCHMAIL-DAEMON@%s",
1537 ctl->smtpaddress ? ctl->smtpaddress : fetchmailhost);
1538 stuff_warning(NULL, ctl, "Date: %s", rfc822timestamp());
1539 stuff_warning(NULL, ctl, "MIME-Version: 1.0");
1540 stuff_warning(NULL, ctl, "Content-Transfer-Encoding: 8bit");
1541 stuff_warning(NULL, ctl, "Content-Type: text/plain; charset=\"%s\"", iana_charset);
1546 /* format and ship a warning message line by mail */
1547 /* if rfc2047charset is non-NULL, encode the line (that is assumed to be
1548 * a header line) as per RFC-2047 using rfc2047charset as the character
1550 #if defined(HAVE_STDARG_H)
1551 void stuff_warning(const char *rfc2047charset, struct query *ctl, const char *fmt, ... )
1553 void stuff_warning(rfc2047charset, ctl, fmt, va_alist)
1554 const char *charset;
1556 const char *fmt; /* printf-style format */
1560 /* make huge -- i18n can bulk up error messages a lot */
1561 char buf[2*MSGBUFSIZE+4];
1565 * stuffline() requires its input to be writeable (for CR stripping),
1566 * so we needed to copy the message to a writeable buffer anyway in
1567 * case it was a string constant. We make a virtue of that necessity
1568 * here by supporting stdargs/varargs.
1570 #if defined(HAVE_STDARG_H)
1575 vsnprintf(buf, sizeof(buf) - 2, fmt, ap);
1578 snprintf(buf+strlen(buf), sizeof(buf)-strlen(buf), "\r\n");
1580 /* guard against very long lines */
1581 buf[MSGBUFSIZE+1] = '\r';
1582 buf[MSGBUFSIZE+2] = '\n';
1583 buf[MSGBUFSIZE+3] = '\0';
1585 stuffline(ctl, rfc2047charset != NULL ? rfc2047e(buf, rfc2047charset) : buf);
1588 void close_warning_by_mail(struct query *ctl, struct msgblk *msg)
1589 /* sign and send mailed warnings */
1591 stuff_warning(NULL, ctl, GT_("-- \nThe Fetchmail Daemon"));
1592 close_sink(ctl, msg, TRUE);
1595 /* sink.c ends here */