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.
14 #include "fetchmail.h"
22 #endif /* HAVE_MEMORY_H */
23 #if defined(STDC_HEADERS)
26 #if defined(HAVE_UNISTD_H)
29 #if defined(HAVE_STDARG_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 static void smtp_rset(struct query *ctl)
69 /* reset the mail transaction */
71 if (SMTP_rset(ctl->smtp_socket, ctl->smtphostmode) == SM_UNRECOVERABLE)
73 /* close the bad connection. fetchmail will reconnect for the
79 int smtp_setup(struct query *ctl)
80 /* try to open a socket to the appropriate SMTP server for this query */
82 /* maybe it's time to close the socket in order to force delivery */
83 if (last_smtp_ok > 0 && time((time_t *)NULL) - last_smtp_ok > mytimeout)
88 if (NUM_NONZERO(ctl->batchlimit)) {
89 if (batchcount == ctl->batchlimit)
94 /* if no socket to any SMTP host is already set up, try to open one */
95 if (ctl->smtp_socket == -1)
98 * RFC 1123 requires that the domain name in HELO address is a
99 * "valid principal domain name" for the client host. If we're
100 * running in invisible mode, violate this with malice
101 * aforethought in order to make the Received headers and
102 * logging look right.
104 * In fact this code relies on the RFC1123 requirement that the
105 * SMTP listener must accept messages even if verification of the
106 * HELO name fails (RFC1123 section 5.2.5, paragraph 2).
108 * How we compute the true mailhost name to pass to the
109 * listener doesn't affect behavior on RFC1123-violating
110 * listeners that check for name match; we're going to lose
111 * on those anyway because we can never give them a name
112 * that matches the local machine fetchmail is running on.
113 * What it will affect is the listener's logging.
116 const char *id_me = run.invisible ? ctl->server.truename : fetchmailhost;
118 char *parsed_host = NULL;
123 * Run down the SMTP hunt list looking for a server that's up.
124 * Use both explicit hunt entries (value TRUE) and implicit
125 * (default) ones (value FALSE).
128 phase = LISTENER_WAIT;
130 set_timeout(ctl->server.timeout);
131 for (idp = ctl->smtphunt; idp; idp = idp->next)
134 const char *portnum = SMTP_PORT;
136 ctl->smtphost = idp->id; /* remember last host tried. */
137 if (ctl->smtphost[0]=='/')
139 ctl->smtphostmode = LMTP_MODE;
141 if ((ctl->smtp_socket = UnixOpen(ctl->smtphost))==-1)
146 ctl->smtphostmode = ctl->listener;
147 parsed_host = xstrdup(idp->id);
148 if ((cp = strrchr(parsed_host, '/')))
154 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,
155 ctl->server.plugout, &ai1)) == -1)
162 /* return immediately for ODMR */
163 if (ctl->server.protocol == P_ODMR)
168 return(ctl->smtp_socket); /* success */
171 /* first, probe for ESMTP */
172 if (SMTP_ok(ctl->smtp_socket, ctl->smtphostmode, TIMEOUT_STARTSMTP) == SM_OK &&
173 SMTP_ehlo(ctl->smtp_socket, ctl->smtphostmode, id_me,
174 ctl->server.esmtp_name, ctl->server.esmtp_password,
175 &ctl->server.esmtp_options) == SM_OK)
179 * RFC 1869 warns that some listeners hang up on a failed EHLO,
180 * so it's safest not to assume the socket will still be good.
184 /* if opening for ESMTP failed, try SMTP */
185 if (ctl->smtphost[0]=='/')
187 if ((ctl->smtp_socket = UnixOpen(ctl->smtphost))==-1)
192 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,
193 ctl->server.plugout, &ai1)) == -1)
200 if (SMTP_ok(ctl->smtp_socket, ctl->smtphostmode, TIMEOUT_STARTSMTP) == SM_OK &&
201 SMTP_helo(ctl->smtp_socket, ctl->smtphostmode, id_me) == SM_OK)
210 * RFC 1123 requires that the domain name part of the
211 * RCPT TO address be "canonicalized", that is a FQDN
212 * or MX but not a CNAME. Some listeners (like exim)
213 * enforce this. Now that we have the actual hostname,
214 * compute what we should canonicalize with.
216 xfree(ctl->destaddr);
217 if (ctl->smtpaddress)
218 ctl->destaddr = xstrdup(ctl->smtpaddress);
219 /* parsed_host is smtphost without the /port */
220 else if (parsed_host && parsed_host[0] != 0)
221 ctl->destaddr = xstrdup(parsed_host);
222 /* No smtphost is specified or it is a UNIX socket, then use
223 localhost as a domain part. */
225 ctl->destaddr = xstrdup("localhost");
228 /* end if (ctl->smtp_socket == -1) */
230 if (outlevel >= O_DEBUG && ctl->smtp_socket != -1)
231 report(stdout, GT_("forwarding to %s\n"), ctl->smtphost);
233 return(ctl->smtp_socket);
236 static void sanitize(char *s)
241 for (cp = s; (cp = strchr (cp, '\'')); cp++)
245 char *rcpt_address(struct query *ctl, const char *id,
248 static char addr[HOSTLEN+USERNAMELEN+1000];
252 snprintf(addr, sizeof (addr), "%s", id);
254 else if (usesmtpname && ctl->smtpname)
256 snprintf(addr, sizeof (addr), "%s", ctl->smtpname);
260 snprintf(addr, sizeof (addr), "%s@%s", id, ctl->destaddr);
265 static int send_bouncemail(struct query *ctl, struct msgblk *msg,
266 int userclass, const char *message /* should have \r\n at the end */,
267 int nerrors, char *errors[])
268 /* bounce back an error report a la RFC 1892 */
270 char daemon_name[15 + HOSTLEN] = "MAILER-DAEMON@";
271 char boundary[BUFSIZ];
272 const char *bounce_to;
274 static char *fqdn_of_host = NULL;
275 const char *md1 = "MAILER-DAEMON", *md2 = "MAILER-DAEMON@";
277 /* don't bounce in reply to undeliverable bounces */
278 if (!msg || !msg->return_path[0] ||
279 strcmp(msg->return_path, "<>") == 0 ||
280 strcasecmp(msg->return_path, md1) == 0 ||
281 strncasecmp(msg->return_path, md2, strlen(md2)) == 0)
284 bounce_to = (run.bouncemail ? msg->return_path : run.postmaster);
286 /* can't just use fetchmailhost here, it might be localhost */
287 if (fqdn_of_host == NULL)
288 fqdn_of_host = host_fqdn(0); /* can't afford to bail out and
290 strlcat(daemon_name, fqdn_of_host, sizeof(daemon_name));
292 /* we need only SMTP for this purpose */
293 /* XXX FIXME: hardcoding localhost is nonsense if smtphost can be
295 if ((sock = SockOpen("localhost", SMTP_PORT, NULL, &ai1)) == -1)
298 if (SMTP_ok(sock, SMTP_MODE, TIMEOUT_STARTSMTP) != SM_OK)
304 if (SMTP_helo(sock, SMTP_MODE, fetchmailhost) != SM_OK
305 || SMTP_from(sock, SMTP_MODE, "<>", (char *)NULL) != SM_OK
306 || SMTP_rcpt(sock, SMTP_MODE, bounce_to) != SM_OK
307 || SMTP_data(sock, SMTP_MODE) != SM_OK)
309 SMTP_quit(sock, SMTP_MODE);
314 /* our first duty is to keep the sacred foo counters turning... */
315 snprintf(boundary, sizeof(boundary), "foo-mani-padme-hum-%ld-%ld-%ld",
316 (long)getpid(), (long)getppid(), (long)time(NULL));
318 if (outlevel >= O_VERBOSE)
319 report(stdout, GT_("SMTP: (bounce-message body)\n"));
321 /* this will usually go to sylog... */
322 report(stderr, GT_("mail from %s bounced to %s\n"),
323 daemon_name, bounce_to);
326 /* bouncemail headers */
327 SockPrintf(sock, "Subject: Mail delivery failed: returning message to sender\r\n");
328 SockPrintf(sock, "From: Mail Delivery System <%s>\r\n", daemon_name);
329 SockPrintf(sock, "To: %s\r\n", bounce_to);
330 SockPrintf(sock, "MIME-Version: 1.0\r\n");
331 SockPrintf(sock, "Content-Type: multipart/report; report-type=delivery-status;\r\n\tboundary=\"%s\"\r\n", boundary);
332 SockPrintf(sock, "\r\n");
334 /* RFC1892 part 1 -- human-readable message */
335 SockPrintf(sock, "--%s\r\n", boundary);
336 SockPrintf(sock,"Content-Type: text/plain\r\n");
337 SockPrintf(sock, "\r\n");
338 SockPrintf(sock, "This message was created automatically by mail delivery software.\r\n");
339 SockPrintf(sock, "\r\n");
340 SockPrintf(sock, "A message that you sent could not be delivered to one or more of its\r\n");
341 SockPrintf(sock, "recipients. This is a permanent error.\r\n");
342 SockPrintf(sock, "\r\n");
343 SockPrintf(sock, "Reason: %s", message);
344 SockPrintf(sock, "\r\n");
345 SockPrintf(sock, "The following address(es) failed:\r\n");
353 for (idp = msg->recipients; idp; idp = idp->next)
355 if (idp->val.status.mark == userclass)
358 SockPrintf(sock, "%s\r\n", rcpt_address (ctl, idp->id, 1));
360 if (nerrors == 1) error = errors[0];
361 else if (nerrors <= nusers)
363 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
366 else error = errors[nusers++];
368 SockPrintf(sock, " SMTP error: %s\r\n\r\n", error);
372 /* RFC1892 part 2 -- machine-readable responses */
373 SockPrintf(sock, "--%s\r\n", boundary);
374 SockPrintf(sock,"Content-Type: message/delivery-status\r\n");
375 SockPrintf(sock, "\r\n");
376 SockPrintf(sock, "Reporting-MTA: dns; %s\r\n", fqdn_of_host);
379 for (idp = msg->recipients; idp; idp = idp->next)
380 if (idp->val.status.mark == userclass)
383 /* Minimum RFC1894 compliance + Diagnostic-Code field */
384 SockPrintf(sock, "\r\n");
385 SockPrintf(sock, "Final-Recipient: rfc822; %s\r\n",
386 rcpt_address (ctl, idp->id, 1));
387 SockPrintf(sock, "Last-Attempt-Date: %s\r\n", rfc822timestamp());
388 SockPrintf(sock, "Action: failed\r\n");
391 /* one error applies to all users */
393 else if (nerrors <= nusers)
395 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
399 /* errors correspond 1-1 to selected users */
400 error = errors[nusers++];
402 if (strlen(error) > 9 && isdigit((unsigned char)error[4])
403 && error[5] == '.' && isdigit((unsigned char)error[6])
404 && error[7] == '.' && isdigit((unsigned char)error[8]))
405 /* Enhanced status code available, use it */
406 SockPrintf(sock, "Status: %5.5s\r\n", &(error[4]));
408 /* Enhanced status code not available, fake one */
409 SockPrintf(sock, "Status: %c.0.0\r\n", error[0]);
410 SockPrintf(sock, "Diagnostic-Code: %s\r\n", error);
412 SockPrintf(sock, "\r\n");
415 /* RFC1892 part 3 -- headers of undelivered message */
416 SockPrintf(sock, "--%s\r\n", boundary);
417 SockPrintf(sock, "Content-Type: text/rfc822-headers\r\n");
418 SockPrintf(sock, "\r\n");
421 SockWrite(sock, msg->headers, strlen(msg->headers));
422 SockPrintf(sock, "\r\n");
424 SockPrintf(sock, "--%s--\r\n", boundary);
426 if (SMTP_eom(sock, SMTP_MODE) != SM_OK
427 || SMTP_quit(sock, SMTP_MODE) != SM_OK)
438 static int handle_smtp_report(struct query *ctl, struct msgblk *msg)
439 /* handle SMTP errors based on the content of SMTP_response */
440 /* returns either PS_REFUSED (to delete message from the server),
441 * or PS_TRANSIENT (keeps the message on the server) */
443 int smtperr = atoi(smtp_response);
446 responses[0] = xstrdup(smtp_response);
449 * Note: send_bouncemail message strings are not made subject
450 * to gettext translation because (a) they're going to be
451 * embedded in a text/plain 7bit part, and (b) they're
452 * going to be associated with listener error-response
453 * messages, which are probably in English (none of the
454 * MTAs I know about are internationalized).
456 if (str_find(&ctl->antispam, smtperr))
459 * SMTP listener explicitly refuses to deliver mail
460 * coming from this address, probably due to an
461 * anti-spam domain exclusion. Respect this. Don't
462 * try to ship the message, and don't prevent it from
463 * being deleted. There's no point in bouncing the
464 * email either since most spammers don't put their
465 * real return email address anywhere in the headers
466 * (unless the user insists with the SET SPAMBOUNCE
471 * 571 = sendmail's "unsolicited email refused"
472 * 550 = exim's new antispam response (temporary)
473 * 501 = exim's old antispam response
474 * 554 = Postfix antispam response.
480 snprintf(rejmsg, sizeof(rejmsg),
481 "spam filter or virus scanner rejected message because:\r\n"
482 "%s\r\n", responses[0]);
484 send_bouncemail(ctl, msg, XMIT_ACCEPT,
485 rejmsg, 1, responses);
492 * Suppress error message only if the response specifically
493 * meant `excluded for policy reasons'. We *should* see
494 * an error when the return code is less specific.
497 report(stderr, GT_("%cMTP error: %s\n"),
503 case 552: /* message exceeds fixed maximum message size */
505 * Permanent no-go condition on the
506 * ESMTP server. Don't try to ship the message,
507 * and allow it to be deleted.
510 send_bouncemail(ctl, msg, XMIT_ACCEPT,
511 "This message was too large (SMTP error 552).\r\n",
516 case 553: /* invalid sending domain */
518 * These latter days 553 usually means a spammer is trying to
519 * cover his tracks. We never bouncemail on these, because
520 * (a) the return address is invalid by definition, and
521 * (b) we wouldn't want spammers to get confirmation that
522 * this address is live, anyway.
527 case 530: /* must issue STARTTLS error */
529 * Some SMTP servers insist on encrypted communication
530 * Let's set PS_TRANSIENT, otherwise all messages to be sent
531 * over such server would be blackholed - see RFC 3207.
533 if (outlevel > O_SILENT)
534 report_complete(stdout,
535 GT_("SMTP server requires STARTTLS, keeping message.\n"));
537 return(PS_TRANSIENT);
540 /* bounce non-transient errors back to the sender */
541 if (smtperr >= 500 && smtperr <= 599)
544 send_bouncemail(ctl, msg, XMIT_ACCEPT,
545 "General SMTP/ESMTP error.\r\n",
551 * We're going to end up here on 4xx errors, like:
553 * 451: temporarily unable to identify sender (exim)
554 * 452: temporary out-of-queue-space condition on the ESMTP server.
556 * These are temporary errors. Don't try to ship the message,
557 * and suppress deletion so it can be retried on a future
560 * Bouncemail *might* be appropriate here as a delay
561 * notification (note; if we ever add this, we must make
562 * sure the RFC1894 Action field is "delayed" rather than
563 * "failed"). But it's not really necessary because
564 * these are not actual failures, we're very likely to be
565 * able to recover on the next cycle.
568 return(PS_TRANSIENT);
572 static int handle_smtp_report_without_bounce(struct query *ctl, struct msgblk *msg)
573 /* handle SMTP errors based on the content of SMTP_response */
574 /* atleast one PS_TRANSIENT: do not send the bounce mail, keep the mail;
575 * no PS_TRANSIENT, atleast one PS_SUCCESS: send the bounce mail, delete the mail;
576 * no PS_TRANSIENT, no PS_SUCCESS: do not send the bounce mail, delete the mail */
578 int smtperr = atoi(smtp_response);
582 if (str_find(&ctl->antispam, smtperr))
590 report(stderr, GT_("%cMTP error: %s\n"),
596 case 552: /* message exceeds fixed maximum message size */
601 case 553: /* invalid sending domain */
605 /* bounce non-transient errors back to the sender */
606 if (smtperr >= 500 && smtperr <= 599)
608 return(PS_TRANSIENT);
612 /* these are shared by open_sink and stuffline */
615 int stuffline(struct query *ctl, char *buf)
616 /* ship a line to the given control block's output sink (SMTP server or MDA) */
624 /* The line may contain NUL characters. Find the last char to use
625 * -- the real line termination is the sequence "\n\0".
627 last = buf + 1; /* last[-1] must be valid! */
628 while ((last += strlen(last)) && (last[-1] != '\n'))
631 /* fix message lines that have only \n termination (for qmail) */
634 if (last - 1 == buf || last[-2] != '\r')
643 phase = FORWARDING_WAIT;
646 * SMTP byte-stuffing. We only do this if the protocol does *not*
647 * use .<CR><LF> as EOM. If it does, the server will already have
648 * decorated any . lines it sends back up.
652 if (ctl->server.base_protocol->delimited) /* server has already byte-stuffed */
655 /* writing to MDA, undo byte-stuffing */
658 /* writing to SMTP, leave the byte-stuffing in place */;
661 else /* if (!protocol->delimited) -- not byte-stuffed already */
666 n = SockWrite(ctl->smtp_socket, buf, 1);
668 n = fwrite(buf, 1, 1, sinkfp);
669 if (ferror(sinkfp)) n = -1;
677 /* we may need to strip carriage returns */
682 for (sp = tp = buf; sp < last; sp++)
690 if (ctl->mda || ctl->bsmtp) {
691 n = fwrite(buf, 1, last - buf, sinkfp);
692 if (ferror(sinkfp)) n = -1;
693 } else if (ctl->smtp_socket != -1)
694 n = SockWrite(ctl->smtp_socket, buf, last - buf);
701 static int open_bsmtp_sink(struct query *ctl, struct msgblk *msg,
702 int *good_addresses, int *bad_addresses)
703 /* open a BSMTP stream */
708 if (strcmp(ctl->bsmtp, "-") == 0)
711 sinkfp = fopen(ctl->bsmtp, "a");
713 if (!sinkfp || ferror(sinkfp)) {
714 report(stderr, GT_("BSMTP file open failed: %s\n"),
719 /* see the ap computation under the SMTP branch */
720 need_anglebrs = (msg->return_path[0] != '<');
723 need_anglebrs ? "<" : "",
724 (msg->return_path[0]) ? msg->return_path : user,
725 need_anglebrs ? ">" : "");
727 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
728 fputs(" BODY=8BITMIME", sinkfp);
729 else if (ctl->mimemsg & MSG_IS_7BIT)
730 fputs(" BODY=7BIT", sinkfp);
732 /* exim's BSMTP processor does not handle SIZE */
733 /* fprintf(sinkfp, " SIZE=%d", msg->reallen); */
735 fprintf(sinkfp, "\r\n");
738 * RFC 1123 requires that the domain name part of the
739 * RCPT TO address be "canonicalized", that is a FQDN
740 * or MX but not a CNAME. Some listeners (like exim)
741 * enforce this. Now that we have the actual hostname,
742 * compute what we should canonicalize with.
744 xfree(ctl->destaddr);
745 ctl->destaddr = xstrdup(ctl->smtpaddress ? ctl->smtpaddress : "localhost");
748 for (idp = msg->recipients; idp; idp = idp->next)
749 if (idp->val.status.mark == XMIT_ACCEPT)
751 fprintf(sinkfp, "RCPT TO:<%s>\r\n",
752 rcpt_address (ctl, idp->id, 1));
756 fputs("DATA\r\n", sinkfp);
758 if (fflush(sinkfp) || ferror(sinkfp))
760 report(stderr, GT_("BSMTP preamble write failed: %s.\n"), strerror(errno));
767 /* this is experimental and will be removed if double bounces are reported */
768 #define EXPLICIT_BOUNCE_ON_BAD_ADDRESS
771 static const char *is_quad(const char *q)
772 /* Check if the string passed in points to what could be one quad of a
773 * dotted-quad IP address. Requirements are that the string is not a
774 * NULL pointer, begins with a period (which is skipped) or a digit
775 * and ends with a period or a NULL. If these requirements are met, a
776 * pointer to the last character (the period or the NULL character) is
777 * returned; otherwise NULL.
786 for(r=q;isdigit((unsigned char)*r);r++)
788 if ( ((*r) && (*r != '.')) || ((r-q) < 1) || ((r-q)>3) )
790 /* Make sure quad is < 255 */
799 else if (*(q+1) == '5')
809 static int is_dottedquad(const char *hostname)
810 /* Returns a true value if the passed in string looks like an IP
811 * address in dotted-quad form, and a false value otherwise.
815 return ((hostname=is_quad(is_quad(is_quad(is_quad(hostname))))) != NULL) &&
819 static int open_smtp_sink(struct query *ctl, struct msgblk *msg,
820 int *good_addresses, int *bad_addresses /* this must be signed, to prevent endless loop in from_addresses */)
821 /* open an SMTP stream */
825 char options[MSGBUFSIZE];
826 char addr[HOSTLEN+USERNAMELEN+1000];
827 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
828 char **from_responses;
829 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
831 int force_transient_error = 0;
835 * Compute ESMTP options.
838 if (ctl->server.esmtp_options & ESMTP_8BITMIME) {
839 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
840 strcpy(options, " BODY=8BITMIME");
841 else if (ctl->mimemsg & MSG_IS_7BIT)
842 strcpy(options, " BODY=7BIT");
845 if ((ctl->server.esmtp_options & ESMTP_SIZE) && msg->reallen > 0)
846 sprintf(options + strlen(options), " SIZE=%d", msg->reallen);
849 * Try to get the SMTP listener to take the Return-Path
850 * address as MAIL FROM. If it won't, fall back on the
851 * remotename and mailserver host. This won't affect replies,
852 * which use the header From address anyway; the MAIL FROM
853 * address is a place for the SMTP listener to send
854 * bouncemail. The point is to guarantee a FQDN in the MAIL
855 * FROM line -- some SMTP listeners, like smail, become
858 * RFC 1123 requires that the domain name part of the
859 * MAIL FROM address be "canonicalized", that is a
860 * FQDN or MX but not a CNAME. We'll assume the Return-Path
861 * header is already in this form here (it certainly
862 * is if rewrite is on). RFC 1123 is silent on whether
863 * a nonexistent hostname part is considered canonical.
865 * This is a potential problem if the MTAs further upstream
866 * didn't pass canonicalized From/Return-Path lines, *and* the
867 * local SMTP listener insists on them.
869 * Handle the case where an upstream MTA is setting a return
870 * path equal to "@". Ghod knows why anyone does this, but
871 * it's been reported to happen in mail from Amazon.com and
874 * Also, if the hostname is a dotted quad, wrap it in square brackets.
875 * Apparently this is required by RFC2821, section 4.1.3.
877 if (!msg->return_path[0] || (msg->return_path[0] == '@'))
879 if (strchr(ctl->remotename,'@') || strchr(ctl->remotename,'!'))
881 snprintf(addr, sizeof(addr), "%s", ctl->remotename);
883 else if (is_dottedquad(ctl->server.truename))
885 snprintf(addr, sizeof(addr), "%s@[%s]", ctl->remotename,
886 ctl->server.truename);
890 snprintf(addr, sizeof(addr),
891 "%s@%s", ctl->remotename, ctl->server.truename);
895 else if (strchr(msg->return_path,'@') || strchr(msg->return_path,'!'))
896 ap = msg->return_path;
897 /* in case Return-Path was "<>" we want to preserve that */
898 else if (strcmp(msg->return_path,"<>") == 0)
899 ap = msg->return_path;
900 else /* in case Return-Path existed but was local */
902 if (is_dottedquad(ctl->server.truename))
904 snprintf(addr, sizeof(addr), "%s@[%s]", msg->return_path,
905 ctl->server.truename);
909 snprintf(addr, sizeof(addr), "%s@%s",
910 msg->return_path, ctl->server.truename);
915 if ((smtp_err = SMTP_from(ctl->smtp_socket, ctl->smtphostmode,
916 ap, options)) == SM_UNRECOVERABLE)
919 return(PS_TRANSIENT);
921 if (smtp_err != SM_OK)
923 int err = handle_smtp_report(ctl, msg); /* map to PS_TRANSIENT or PS_REFUSED */
925 smtp_rset(ctl); /* stay on the safe side */
930 * Now list the recipient addressees
933 for (idp = msg->recipients; idp; idp = idp->next)
935 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
936 from_responses = (char **)xmalloc(sizeof(char *) * total_addresses);
937 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
938 for (idp = msg->recipients; idp; idp = idp->next)
939 if (idp->val.status.mark == XMIT_ACCEPT)
942 address = rcpt_address (ctl, idp->id, 1);
943 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket, ctl->smtphostmode,
944 address)) == SM_UNRECOVERABLE)
948 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
949 while (*bad_addresses)
950 free(from_responses[--*bad_addresses]);
951 free(from_responses);
952 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
953 return(PS_TRANSIENT);
955 if (smtp_err == SM_OK)
959 switch (handle_smtp_report_without_bounce(ctl, msg))
962 force_transient_error = 1;
966 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
967 from_responses[*bad_addresses] = xstrdup(smtp_response);
968 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
971 idp->val.status.mark = XMIT_RCPTBAD;
972 if (outlevel >= O_VERBOSE)
974 GT_("%cMTP listener doesn't like recipient address `%s'\n"),
975 ctl->smtphostmode, address);
979 if (outlevel >= O_VERBOSE)
981 GT_("%cMTP listener doesn't really like recipient address `%s'\n"),
982 ctl->smtphostmode, address);
988 if (force_transient_error) {
989 /* do not risk dataloss due to overengineered multidrop
990 * crap. If one of the recipients returned PS_TRANSIENT,
991 * we return exactly that.
993 smtp_rset(ctl); /* required by RFC1870 */
996 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
998 * This should not be necessary, because the SMTP listener itself
999 * should generate a bounce for the bad address.
1001 * XXX FIXME 2006-01-19: is this comment true? I don't think
1002 * it is, because the SMTP listener isn't required to accept bogus
1003 * messages. There appears to be general SMTP<->MDA and
1004 * responsibility confusion.
1007 send_bouncemail(ctl, msg, XMIT_RCPTBAD,
1008 "Some addresses were rejected by the MDA fetchmail forwards to.\r\n",
1009 *bad_addresses, from_responses);
1010 while (*bad_addresses)
1011 free(from_responses[--*bad_addresses]);
1012 free(from_responses);
1013 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
1016 * It's tempting to do local notification only if bouncemail was
1017 * insufficient -- that is, to add && total_addresses > *bad_addresses
1018 * to the test here. The problem with this theory is that it would
1019 * make initial diagnosis of a broken multidrop configuration very
1020 * hard -- most single-recipient messages would just invisibly bounce.
1022 if (!(*good_addresses))
1024 if (!run.postmaster[0])
1026 if (outlevel >= O_VERBOSE)
1027 report(stderr, GT_("no address matches; no postmaster set.\n"));
1028 smtp_rset(ctl); /* required by RFC1870 */
1031 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket, ctl->smtphostmode,
1032 rcpt_address (ctl, run.postmaster, 0))) == SM_UNRECOVERABLE)
1035 return(PS_TRANSIENT);
1037 if (smtp_err != SM_OK)
1039 report(stderr, GT_("can't even send to %s!\n"), run.postmaster);
1040 smtp_rset(ctl); /* required by RFC1870 */
1044 if (outlevel >= O_VERBOSE)
1045 report(stderr, GT_("no address matches; forwarding to %s.\n"), run.postmaster);
1049 * Tell the listener we're ready to send data.
1050 * Some listeners (like zmailer) may return antispam errors here.
1052 if ((smtp_err = SMTP_data(ctl->smtp_socket, ctl->smtphostmode))
1053 == SM_UNRECOVERABLE)
1056 return(PS_TRANSIENT);
1058 if (smtp_err != SM_OK)
1060 int err = handle_smtp_report(ctl, msg);
1061 smtp_rset(ctl); /* stay on the safe side */
1066 * We need to stash this away in order to know how many
1067 * response lines to expect after the LMTP end-of-message.
1069 lmtp_responses = *good_addresses;
1074 static int open_mda_sink(struct query *ctl, struct msgblk *msg,
1075 int *good_addresses, int *bad_addresses)
1076 /* open a stream to a local MDA */
1080 #endif /* HAVE_SETEUID */
1082 int length = 0, fromlen = 0, nameslen = 0;
1083 char *names = NULL, *before, *after, *from = NULL;
1085 (void)bad_addresses;
1086 xfree(ctl->destaddr);
1087 ctl->destaddr = xstrdup("localhost");
1089 for (idp = msg->recipients; idp; idp = idp->next)
1090 if (idp->val.status.mark == XMIT_ACCEPT)
1091 (*good_addresses)++;
1093 length = strlen(ctl->mda);
1094 before = xstrdup(ctl->mda);
1096 /* get user addresses for %T (or %s for backward compatibility) */
1097 if (strstr(before, "%s") || strstr(before, "%T"))
1100 * We go through this in order to be able to handle very
1101 * long lists of users and (re)implement %s.
1104 for (idp = msg->recipients; idp; idp = idp->next)
1105 if (idp->val.status.mark == XMIT_ACCEPT)
1106 nameslen += (strlen(idp->id) + 1); /* string + ' ' */
1107 if (*good_addresses == 0)
1108 nameslen = strlen(run.postmaster);
1110 names = (char *)xmalloc(nameslen + 1); /* account for '\0' */
1111 if (*good_addresses == 0)
1112 strcpy(names, run.postmaster);
1116 for (idp = msg->recipients; idp; idp = idp->next)
1117 if (idp->val.status.mark == XMIT_ACCEPT)
1119 strcat(names, idp->id);
1122 names[--nameslen] = '\0'; /* chop trailing space */
1128 /* get From address for %F */
1129 if (strstr(before, "%F"))
1131 from = xstrdup(msg->return_path);
1135 fromlen = strlen(from);
1138 /* do we have to build an mda string? */
1143 /* find length of resulting mda string */
1145 while ((sp = strstr(sp, "%s"))) {
1146 length += nameslen; /* subtract %s and add '' */
1150 while ((sp = strstr(sp, "%T"))) {
1151 length += nameslen; /* subtract %T and add '' */
1155 while ((sp = strstr(sp, "%F"))) {
1156 length += fromlen; /* subtract %F and add '' */
1160 after = (char *)xmalloc(length + 1);
1162 /* copy mda source string to after, while expanding %[sTF] */
1163 for (dp = after, sp = before; (*dp = *sp); dp++, sp++) {
1164 if (sp[0] != '%') continue;
1166 if (sp > before && sp[-1] == '\'') {
1167 report(stderr, GT_("MDA option contains single-quoted %%%c expansion.\n"), sp[1]);
1168 report(stderr, GT_("Refusing to deliver. Check the manual and fix your mda option.\n"));
1171 if (from) free(from);
1172 if (names) free(names);
1176 /* need to expand? BTW, no here overflow, because in
1177 ** the worst case (end of string) sp[1] == '\0' */
1178 if (sp[1] == 's' || sp[1] == 'T') {
1180 if (names) strcpy(dp, names);
1183 sp++; /* position sp over [sT] */
1184 dp--; /* adjust dp */
1185 } else if (sp[1] == 'F') {
1187 if (from) strcpy(dp, from);
1190 sp++; /* position sp over F */
1191 dp--; /* adjust dp */
1210 if (outlevel >= O_DEBUG)
1211 report(stdout, GT_("about to deliver with: %s\n"), before);
1215 * Arrange to run with user's permissions if we're root.
1216 * This will initialize the ownership of any files the
1217 * MDA creates properly. (The seteuid call is available
1218 * under all BSDs and Linux)
1220 orig_uid = getuid();
1221 if (seteuid(ctl->uid)) {
1222 report(stderr, GT_("Cannot switch effective user id to %ld: %s\n"), (long)ctl->uid, strerror(errno));
1225 #endif /* HAVE_SETEUID */
1227 sinkfp = popen(before, "w");
1232 /* this will fail quietly if we didn't start as root */
1233 if (seteuid(orig_uid)) {
1234 report(stderr, GT_("Cannot switch effective user id back to original %ld: %s\n"), (long)orig_uid, strerror(errno));
1237 #endif /* HAVE_SETEUID */
1241 report(stderr, GT_("MDA open failed\n"));
1246 * We need to disable the normal SIGCHLD handling here because
1247 * sigchld_handler() would reap away the error status, returning
1248 * error status instead of 0 for successful completion.
1250 set_signal_handler(SIGCHLD, SIG_DFL);
1255 int open_sink(struct query *ctl, struct msgblk *msg,
1256 int *good_addresses, int *bad_addresses)
1257 /* set up sinkfp to be an input sink we can ship a message to */
1259 *bad_addresses = *good_addresses = 0;
1261 if (want_progress() && outlevel >= O_VERBOSE && !ctl->mda && !ctl->bsmtp) puts("");
1263 if (ctl->bsmtp) /* dump to a BSMTP batch file */
1264 return(open_bsmtp_sink(ctl, msg, good_addresses, bad_addresses));
1266 * Try to forward to an SMTP or LMTP listener. If the attempt to
1267 * open a socket fails, fall through to attempt delivery via
1270 else if (!ctl->mda && smtp_setup(ctl) != -1)
1271 return(open_smtp_sink(ctl, msg, good_addresses, bad_addresses));
1274 * Awkward case. User didn't specify an MDA. Our attempt to get a
1275 * listener socket failed. Try to cope anyway -- initial configuration
1276 * may have found procmail.
1280 report(stderr, GT_("%cMTP connect to %s failed\n"),
1282 ctl->smtphost ? ctl->smtphost : "localhost");
1284 #ifndef FALLBACK_MDA
1285 /* No fallback MDA declared. Bail out. */
1289 * If user had things set up to forward offsite, no way
1290 * we want to deliver locally!
1292 if (ctl->smtphost && strcmp(ctl->smtphost, "localhost"))
1296 * User was delivering locally. We have a fallback MDA.
1297 * Latch it in place, logging the error, and fall through.
1298 * Set stripcr as we would if MDA had been the initial transport
1300 ctl->mda = FALLBACK_MDA;
1302 ctl->stripcr = TRUE;
1304 report(stderr, GT_("can't raise the listener; falling back to %s"),
1309 if (ctl->mda) /* must deliver through an MDA */
1310 return(open_mda_sink(ctl, msg, good_addresses, bad_addresses));
1315 void release_sink(struct query *ctl)
1316 /* release the per-message output sink, whether it's a pipe or SMTP socket */
1318 if (ctl->bsmtp && sinkfp)
1320 if (strcmp(ctl->bsmtp, "-"))
1323 sinkfp = (FILE *)NULL;
1331 sinkfp = (FILE *)NULL;
1333 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1337 int close_sink(struct query *ctl, struct msgblk *msg, flag forward)
1338 /* perform end-of-message actions on the current output sink */
1342 if (want_progress() && outlevel >= O_VERBOSE && !ctl->mda && !ctl->bsmtp) puts("");
1344 if (ctl->bsmtp && sinkfp) {
1347 /* implicit disk-full check here... */
1348 fputs(".\r\n", sinkfp);
1349 error = ferror(sinkfp);
1351 if (strcmp(ctl->bsmtp, "-"))
1353 if (fclose(sinkfp) == EOF) {
1357 sinkfp = (FILE *)NULL;
1362 GT_("Message termination or close of BSMTP file failed: %s\n"), strerror(oerrno));
1365 } else if (ctl->mda) {
1366 int rc = 0, e = 0, e2 = 0, err = 0;
1368 /* close the delivery pipe, we'll reopen before next message */
1372 err = 1, e2 = errno;
1373 if ((fflush(sinkfp)))
1374 err = 1, e2 = errno;
1377 rc = pclose(sinkfp);
1379 sinkfp = (FILE *)NULL;
1382 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1387 report(stderr, GT_("Error writing to MDA: %s\n"), strerror(e2));
1388 } else if (WIFSIGNALED(rc)) {
1390 GT_("MDA died of signal %d\n"), WTERMSIG(rc));
1391 } else if (WIFEXITED(rc)) {
1393 GT_("MDA returned nonzero status %d\n"), WEXITSTATUS(rc));
1396 GT_("Strange: MDA pclose returned %d and errno %d/%s, cannot handle at %s:%d\n"),
1397 rc, e, strerror(e), __FILE__, __LINE__);
1405 /* write message terminator */
1406 if ((smtp_err = SMTP_eom(ctl->smtp_socket, ctl->smtphostmode))
1407 == SM_UNRECOVERABLE)
1412 if (smtp_err != SM_OK)
1414 if (handle_smtp_report(ctl, msg) != PS_REFUSED)
1416 smtp_rset(ctl); /* stay on the safe side */
1421 report(stderr, GT_("SMTP listener refused delivery\n"));
1422 smtp_rset(ctl); /* stay on the safe side */
1428 * If this is an SMTP connection, SMTP_eom() ate the response.
1429 * But could be this is an LMTP connection, in which case we have to
1430 * interpret either (a) a single 503 response meaning there
1431 * were no successful RCPT TOs, or (b) a variable number of
1432 * responses, one for each successful RCPT TO. We need to send
1433 * bouncemail on each failed response and then return TRUE anyway,
1434 * otherwise the message will get left in the queue and resent
1435 * to people who got it the first time.
1437 if (ctl->smtphostmode == LMTP_MODE)
1439 if (lmtp_responses == 0)
1441 SMTP_ok(ctl->smtp_socket, ctl->smtphostmode, TIMEOUT_EOM);
1444 * According to RFC2033, 503 is the only legal response
1445 * if no RCPT TO commands succeeded. No error recovery
1446 * is really possible here, as we have no idea what
1447 * insane thing the listener might be doing if it doesn't
1450 if (atoi(smtp_response) == 503)
1451 report(stderr, GT_("LMTP delivery error on EOM\n"));
1454 GT_("Unexpected non-503 response to LMTP EOM: %s\n"),
1458 * It's not completely clear what to do here. We choose to
1459 * interpret delivery failure here as a transient error,
1460 * the same way SMTP delivery failure is handled. If we're
1461 * wrong, an undead message will get stuck in the queue.
1467 int i, errors, rc = FALSE;
1470 /* eat the RFC2033-required responses, saving errors */
1471 responses = (char **)xmalloc(sizeof(char *) * lmtp_responses);
1472 for (errors = i = 0; i < lmtp_responses; i++)
1474 if ((smtp_err = SMTP_ok(ctl->smtp_socket, ctl->smtphostmode, TIMEOUT_EOM))
1475 == SM_UNRECOVERABLE)
1480 if (smtp_err != SM_OK)
1483 * amavis returns the SMTP code from the recieving
1484 * host after the DATA-DOT. So we need to compare the
1485 * response to the antispam option here instead.
1487 if (handle_smtp_report(ctl, msg) != PS_REFUSED) {
1488 /* Only count an error if the message was not refused */
1489 responses[errors] = xstrdup(smtp_response);
1496 rc = TRUE; /* all deliveries succeeded */
1499 * One or more deliveries failed.
1500 * If we can bounce a failures list back to the
1501 * sender, and the postmaster does not want to
1502 * deal with the bounces return TRUE, deleting the
1503 * message from the server so it won't be
1504 * re-forwarded on subsequent poll cycles.
1506 rc = send_bouncemail(ctl, msg, XMIT_ACCEPT,
1507 "LMTP partial delivery failure.\r\n",
1511 for (i = 0; i < errors; i++)
1522 int open_warning_by_mail(struct query *ctl)
1523 /* set up output sink for a mailed warning to calling user */
1528 * Dispatching warning email is a little complicated. The problem is
1529 * that we have to deal with three distinct cases:
1531 * 1. Single-drop running from user account. Warning mail should
1532 * go to the local name for which we're collecting (coincides
1533 * with calling user).
1535 * 2. Single-drop running from root or other privileged ID, with rc
1536 * file generated on the fly (Ken Estes's weird setup...) Mail
1537 * should go to the local name for which we're collecting (does not
1538 * coincide with calling user).
1540 * 3. Multidrop. Mail must go to postmaster. We leave the recipients
1541 * member null so this message will fall through to run.postmaster.
1543 * The zero in the reallen element means we won't pass a SIZE
1544 * option to ESMTP; the message length would be more trouble than
1545 * it's worth to compute.
1547 struct msgblk reply = {NULL, NULL, "FETCHMAIL-DAEMON@", 0, 0};
1550 strlcat(reply.return_path, ctl->smtpaddress ? ctl->smtpaddress :
1551 fetchmailhost, sizeof(reply.return_path));
1553 if (!MULTIDROP(ctl)) /* send to calling user */
1555 save_str(&reply.recipients, ctl->localnames->id, XMIT_ACCEPT);
1556 status = open_sink(ctl, &reply, &good, &bad);
1557 free_str_list(&reply.recipients);
1559 else /* send to postmaster */
1560 status = open_sink(ctl, &reply, &good, &bad);
1562 stuff_warning(NULL, ctl, "From: ", "FETCHMAIL-DAEMON@%s",
1563 ctl->smtpaddress ? ctl->smtpaddress : fetchmailhost);
1564 stuff_warning(NULL, ctl, "Date: ", "%s", rfc822timestamp());
1565 stuff_warning(NULL, ctl, "MIME-Version: ", "1.0");
1566 stuff_warning(NULL, ctl, "Content-Transfer-Encoding: ", "8bit");
1567 stuff_warning(NULL, ctl, "Content-Type: ", "text/plain; charset=\"%s\"", iana_charset);
1572 /* format and ship a warning message line by mail */
1573 /* if rfc2047charset is non-NULL, encode the line (that is assumed to be
1574 * a header line) as per RFC-2047 using rfc2047charset as the character
1576 #if defined(HAVE_STDARG_H)
1577 void stuff_warning(const char *rfc2047charset, struct query *ctl, const char *pfx, const char *fmt, ... )
1579 void stuff_warning(rfc2047charset, ctl, pfx, fmt, va_alist)
1580 const char *charset;
1581 const char *pfx; /* constant, non-translated prefix (such as "Subject: ") */
1583 const char *fmt; /* printf-style format */
1587 /* make huge -- i18n can bulk up error messages a lot */
1588 char buf[3*MSGBUFSIZE+4];
1591 snprintf(buf, sizeof(buf), "%s", pfx);
1594 * stuffline() requires its input to be writeable (for CR stripping),
1595 * so we needed to copy the message to a writeable buffer anyway in
1596 * case it was a string constant. We make a virtue of that necessity
1597 * here by supporting stdargs/varargs.
1599 #if defined(HAVE_STDARG_H)
1604 vsnprintf(buf+strlen(buf), sizeof(buf)-strlen(buf)-2, fmt, ap);
1607 snprintf(buf+strlen(buf), sizeof(buf)-strlen(buf), "\r\n");
1609 /* guard against very long lines */
1610 buf[MSGBUFSIZE+1] = '\r';
1611 buf[MSGBUFSIZE+2] = '\n';
1612 buf[MSGBUFSIZE+3] = '\0';
1614 stuffline(ctl, rfc2047charset != NULL ? rfc2047e(buf, rfc2047charset) : buf);
1617 void close_warning_by_mail(struct query *ctl, struct msgblk *msg)
1618 /* sign and send mailed warnings */
1620 stuff_warning(NULL, ctl, "-- \n", GT_("The Fetchmail Daemon"));
1621 close_sink(ctl, msg, TRUE);
1624 /* sink.c ends here */