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.
24 #include "fetchmail.h"
26 /* for W* macros after pclose() */
28 #include <sys/types.h>
29 #include <sys/resource.h>
36 /* BSD portability hack...I know, this is an ugly place to put it */
37 #if !defined(SIGCHLD) && defined(SIGCLD)
38 #define SIGCHLD SIGCLD
41 /* makes the open_sink()/close_sink() pair non-reentrant */
42 static int lmtp_responses;
44 void smtp_close(struct query *ctl, int sayquit)
45 /* close the socket to SMTP server */
47 if (ctl->smtp_socket != -1)
50 SMTP_quit(ctl->smtp_socket, ctl->smtphostmode);
51 SockClose(ctl->smtp_socket);
52 ctl->smtp_socket = -1;
57 static void smtp_rset(struct query *ctl)
58 /* reset the mail transaction */
60 if (SMTP_rset(ctl->smtp_socket, ctl->smtphostmode) == SM_UNRECOVERABLE)
62 /* close the bad connection. fetchmail will reconnect for the
68 int smtp_setup(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;
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 const 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, TIMEOUT_STARTSMTP) == 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, TIMEOUT_STARTSMTP) == 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, const 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];
260 const char *bounce_to;
262 static char *fqdn_of_host = NULL;
263 const char *md1 = "MAILER-DAEMON", *md2 = "MAILER-DAEMON@";
265 /* don't bounce in reply to undeliverable bounces */
266 if (!msg || !msg->return_path[0] ||
267 strcmp(msg->return_path, "<>") == 0 ||
268 strcasecmp(msg->return_path, md1) == 0 ||
269 strncasecmp(msg->return_path, md2, strlen(md2)) == 0)
272 bounce_to = (run.bouncemail ? msg->return_path : run.postmaster);
274 /* can't just use fetchmailhost here, it might be localhost */
275 if (fqdn_of_host == NULL)
276 fqdn_of_host = host_fqdn(0); /* can't afford to bail out and
278 strlcat(daemon_name, fqdn_of_host, sizeof(daemon_name));
280 /* we need only SMTP for this purpose */
281 /* XXX FIXME: hardcoding localhost is nonsense if smtphost can be
283 if ((sock = SockOpen("localhost", SMTP_PORT, NULL, &ai1)) == -1)
286 if (SMTP_ok(sock, SMTP_MODE, TIMEOUT_STARTSMTP) != SM_OK)
292 if (SMTP_helo(sock, SMTP_MODE, fetchmailhost) != SM_OK
293 || SMTP_from(sock, SMTP_MODE, "<>", (char *)NULL) != SM_OK
294 || SMTP_rcpt(sock, SMTP_MODE, bounce_to) != SM_OK
295 || SMTP_data(sock, SMTP_MODE) != SM_OK)
297 SMTP_quit(sock, SMTP_MODE);
302 /* our first duty is to keep the sacred foo counters turning... */
303 snprintf(boundary, sizeof(boundary), "foo-mani-padme-hum-%ld-%ld-%ld",
304 (long)getpid(), (long)getppid(), (long)time(NULL));
306 if (outlevel >= O_VERBOSE)
307 report(stdout, GT_("SMTP: (bounce-message body)\n"));
309 /* this will usually go to sylog... */
310 report(stderr, GT_("mail from %s bounced to %s\n"),
311 daemon_name, bounce_to);
314 /* bouncemail headers */
315 SockPrintf(sock, "Subject: Mail delivery failed: returning message to sender\r\n");
316 SockPrintf(sock, "From: Mail Delivery System <%s>\r\n", daemon_name);
317 SockPrintf(sock, "To: %s\r\n", bounce_to);
318 SockPrintf(sock, "MIME-Version: 1.0\r\n");
319 SockPrintf(sock, "Content-Type: multipart/report; report-type=delivery-status;\r\n\tboundary=\"%s\"\r\n", boundary);
320 SockPrintf(sock, "\r\n");
322 /* RFC1892 part 1 -- human-readable message */
323 SockPrintf(sock, "--%s\r\n", boundary);
324 SockPrintf(sock,"Content-Type: text/plain\r\n");
325 SockPrintf(sock, "\r\n");
326 SockPrintf(sock, "This message was created automatically by mail delivery software.\r\n");
327 SockPrintf(sock, "\r\n");
328 SockPrintf(sock, "A message that you sent could not be delivered to one or more of its\r\n");
329 SockPrintf(sock, "recipients. This is a permanent error.\r\n");
330 SockPrintf(sock, "\r\n");
331 SockPrintf(sock, "Reason: %s", message);
332 SockPrintf(sock, "\r\n");
333 SockPrintf(sock, "The following address(es) failed:\r\n");
341 for (idp = msg->recipients; idp; idp = idp->next)
343 if (idp->val.status.mark == userclass)
346 SockPrintf(sock, "%s\r\n", rcpt_address (ctl, idp->id, 1));
348 if (nerrors == 1) error = errors[0];
349 else if (nerrors <= nusers)
351 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
354 else error = errors[nusers++];
356 SockPrintf(sock, " SMTP error: %s\r\n\r\n", error);
360 /* RFC1892 part 2 -- machine-readable responses */
361 SockPrintf(sock, "--%s\r\n", boundary);
362 SockPrintf(sock,"Content-Type: message/delivery-status\r\n");
363 SockPrintf(sock, "\r\n");
364 SockPrintf(sock, "Reporting-MTA: dns; %s\r\n", fqdn_of_host);
367 for (idp = msg->recipients; idp; idp = idp->next)
368 if (idp->val.status.mark == userclass)
371 /* Minimum RFC1894 compliance + Diagnostic-Code field */
372 SockPrintf(sock, "\r\n");
373 SockPrintf(sock, "Final-Recipient: rfc822; %s\r\n",
374 rcpt_address (ctl, idp->id, 1));
375 SockPrintf(sock, "Last-Attempt-Date: %s\r\n", rfc822timestamp());
376 SockPrintf(sock, "Action: failed\r\n");
379 /* one error applies to all users */
381 else if (nerrors <= nusers)
383 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
387 /* errors correspond 1-1 to selected users */
388 error = errors[nusers++];
390 if (strlen(error) > 9 && isdigit((unsigned char)error[4])
391 && error[5] == '.' && isdigit((unsigned char)error[6])
392 && error[7] == '.' && isdigit((unsigned char)error[8]))
393 /* Enhanced status code available, use it */
394 SockPrintf(sock, "Status: %5.5s\r\n", &(error[4]));
396 /* Enhanced status code not available, fake one */
397 SockPrintf(sock, "Status: %c.0.0\r\n", error[0]);
398 SockPrintf(sock, "Diagnostic-Code: %s\r\n", error);
400 SockPrintf(sock, "\r\n");
403 /* RFC1892 part 3 -- headers of undelivered message */
404 SockPrintf(sock, "--%s\r\n", boundary);
405 SockPrintf(sock, "Content-Type: text/rfc822-headers\r\n");
406 SockPrintf(sock, "\r\n");
409 SockWrite(sock, msg->headers, strlen(msg->headers));
410 SockPrintf(sock, "\r\n");
412 SockPrintf(sock, "--%s--\r\n", boundary);
414 if (SMTP_eom(sock, SMTP_MODE) != SM_OK
415 || SMTP_quit(sock, SMTP_MODE) != SM_OK)
426 static int handle_smtp_report(struct query *ctl, struct msgblk *msg)
427 /* handle SMTP errors based on the content of SMTP_response */
428 /* returns either PS_REFUSED (to delete message from the server),
429 * or PS_TRANSIENT (keeps the message on the server) */
431 int smtperr = atoi(smtp_response);
434 responses[0] = xstrdup(smtp_response);
437 * Note: send_bouncemail message strings are not made subject
438 * to gettext translation because (a) they're going to be
439 * embedded in a text/plain 7bit part, and (b) they're
440 * going to be associated with listener error-response
441 * messages, which are probably in English (none of the
442 * MTAs I know about are internationalized).
444 if (str_find(&ctl->antispam, smtperr))
447 * SMTP listener explicitly refuses to deliver mail
448 * coming from this address, probably due to an
449 * anti-spam domain exclusion. Respect this. Don't
450 * try to ship the message, and don't prevent it from
451 * being deleted. There's no point in bouncing the
452 * email either since most spammers don't put their
453 * real return email address anywhere in the headers
454 * (unless the user insists with the SET SPAMBOUNCE
459 * 571 = sendmail's "unsolicited email refused"
460 * 550 = exim's new antispam response (temporary)
461 * 501 = exim's old antispam response
462 * 554 = Postfix antispam response.
468 snprintf(rejmsg, sizeof(rejmsg),
469 "spam filter or virus scanner rejected message because:\r\n"
470 "%s\r\n", responses[0]);
472 send_bouncemail(ctl, msg, XMIT_ACCEPT,
473 rejmsg, 1, responses);
480 * Suppress error message only if the response specifically
481 * meant `excluded for policy reasons'. We *should* see
482 * an error when the return code is less specific.
485 report(stderr, GT_("%cMTP error: %s\n"),
491 case 552: /* message exceeds fixed maximum message size */
493 * Permanent no-go condition on the
494 * ESMTP server. Don't try to ship the message,
495 * and allow it to be deleted.
498 send_bouncemail(ctl, msg, XMIT_ACCEPT,
499 "This message was too large (SMTP error 552).\r\n",
504 case 553: /* invalid sending domain */
506 * These latter days 553 usually means a spammer is trying to
507 * cover his tracks. We never bouncemail on these, because
508 * (a) the return address is invalid by definition, and
509 * (b) we wouldn't want spammers to get confirmation that
510 * this address is live, anyway.
515 case 530: /* must issue STARTTLS error */
517 * Some SMTP servers insist on encrypted communication
518 * Let's set PS_TRANSIENT, otherwise all messages to be sent
519 * over such server would be blackholed - see RFC 3207.
521 if (outlevel > O_SILENT)
522 report_complete(stdout,
523 GT_("SMTP server requires STARTTLS, keeping message.\n"));
525 return(PS_TRANSIENT);
528 /* bounce non-transient errors back to the sender */
529 if (smtperr >= 500 && smtperr <= 599)
532 send_bouncemail(ctl, msg, XMIT_ACCEPT,
533 "General SMTP/ESMTP error.\r\n",
539 * We're going to end up here on 4xx errors, like:
541 * 451: temporarily unable to identify sender (exim)
542 * 452: temporary out-of-queue-space condition on the ESMTP server.
544 * These are temporary errors. Don't try to ship the message,
545 * and suppress deletion so it can be retried on a future
548 * Bouncemail *might* be appropriate here as a delay
549 * notification (note; if we ever add this, we must make
550 * sure the RFC1894 Action field is "delayed" rather than
551 * "failed"). But it's not really necessary because
552 * these are not actual failures, we're very likely to be
553 * able to recover on the next cycle.
556 return(PS_TRANSIENT);
560 static int handle_smtp_report_without_bounce(struct query *ctl, struct msgblk *msg)
561 /* handle SMTP errors based on the content of SMTP_response */
562 /* atleast one PS_TRANSIENT: do not send the bounce mail, keep the mail;
563 * no PS_TRANSIENT, atleast one PS_SUCCESS: send the bounce mail, delete the mail;
564 * no PS_TRANSIENT, no PS_SUCCESS: do not send the bounce mail, delete the mail */
566 int smtperr = atoi(smtp_response);
570 if (str_find(&ctl->antispam, smtperr))
578 report(stderr, GT_("%cMTP error: %s\n"),
584 case 552: /* message exceeds fixed maximum message size */
589 case 553: /* invalid sending domain */
590 /* do not send bounce mail - it would feed spammers */
594 /* bounce non-transient errors back to the sender */
595 if (smtperr >= 500 && smtperr <= 599)
597 return(PS_TRANSIENT);
601 /* these are shared by open_sink and stuffline */
604 int stuffline(struct query *ctl, char *buf)
605 /* ship a line to the given control block's output sink (SMTP server or MDA) */
613 /* The line may contain NUL characters. Find the last char to use
614 * -- the real line termination is the sequence "\n\0".
616 last = buf + 1; /* last[-1] must be valid! */
617 while ((last += strlen(last)) && (last[-1] != '\n'))
620 /* fix message lines that have only \n termination (for qmail) */
623 if (last - 1 == buf || last[-2] != '\r')
632 phase = FORWARDING_WAIT;
635 * SMTP byte-stuffing. We only do this if the protocol does *not*
636 * use .<CR><LF> as EOM. If it does, the server will already have
637 * decorated any . lines it sends back up.
641 if (ctl->server.base_protocol->delimited) /* server has already byte-stuffed */
644 /* writing to MDA, undo byte-stuffing */
647 /* writing to SMTP, leave the byte-stuffing in place */;
650 else /* if (!protocol->delimited) -- not byte-stuffed already */
655 n = SockWrite(ctl->smtp_socket, buf, 1);
657 n = fwrite(buf, 1, 1, sinkfp);
658 if (ferror(sinkfp)) n = -1;
666 /* we may need to strip carriage returns */
671 for (sp = tp = buf; sp < last; sp++)
679 if (ctl->mda || ctl->bsmtp) {
680 n = fwrite(buf, 1, last - buf, sinkfp);
681 if (ferror(sinkfp)) n = -1;
682 } else if (ctl->smtp_socket != -1)
683 n = SockWrite(ctl->smtp_socket, buf, last - buf);
690 static int open_bsmtp_sink(struct query *ctl, struct msgblk *msg,
691 int *good_addresses, int *bad_addresses)
692 /* open a BSMTP stream */
697 if (strcmp(ctl->bsmtp, "-") == 0)
700 sinkfp = fopen(ctl->bsmtp, "a");
702 if (!sinkfp || ferror(sinkfp)) {
703 report(stderr, GT_("BSMTP file open failed: %s\n"),
708 /* see the ap computation under the SMTP branch */
709 need_anglebrs = (msg->return_path[0] != '<');
712 need_anglebrs ? "<" : "",
713 (msg->return_path[0]) ? msg->return_path : user,
714 need_anglebrs ? ">" : "");
716 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
717 fputs(" BODY=8BITMIME", sinkfp);
718 else if (ctl->mimemsg & MSG_IS_7BIT)
719 fputs(" BODY=7BIT", sinkfp);
721 /* exim's BSMTP processor does not handle SIZE */
722 /* fprintf(sinkfp, " SIZE=%d", msg->reallen); */
724 fprintf(sinkfp, "\r\n");
727 * RFC 1123 requires that the domain name part of the
728 * RCPT TO address be "canonicalized", that is a FQDN
729 * or MX but not a CNAME. Some listeners (like exim)
730 * enforce this. Now that we have the actual hostname,
731 * compute what we should canonicalize with.
733 xfree(ctl->destaddr);
734 ctl->destaddr = xstrdup(ctl->smtpaddress ? ctl->smtpaddress : "localhost");
737 for (idp = msg->recipients; idp; idp = idp->next)
738 if (idp->val.status.mark == XMIT_ACCEPT)
740 fprintf(sinkfp, "RCPT TO:<%s>\r\n",
741 rcpt_address (ctl, idp->id, 1));
745 fputs("DATA\r\n", sinkfp);
747 if (fflush(sinkfp) || ferror(sinkfp))
749 report(stderr, GT_("BSMTP preamble write failed: %s.\n"), strerror(errno));
756 /* this is experimental and will be removed if double bounces are reported */
757 #define EXPLICIT_BOUNCE_ON_BAD_ADDRESS
760 static const char *is_quad(const char *q)
761 /* Check if the string passed in points to what could be one quad of a
762 * dotted-quad IP address. Requirements are that the string is not a
763 * NULL pointer, begins with a period (which is skipped) or a digit
764 * and ends with a period or a NULL. If these requirements are met, a
765 * pointer to the last character (the period or the NULL character) is
766 * returned; otherwise NULL.
775 for(r=q;isdigit((unsigned char)*r);r++)
777 if ( ((*r) && (*r != '.')) || ((r-q) < 1) || ((r-q)>3) )
779 /* Make sure quad is < 255 */
788 else if (*(q+1) == '5')
798 static int is_dottedquad(const char *hostname)
799 /* Returns a true value if the passed in string looks like an IP
800 * address in dotted-quad form, and a false value otherwise.
804 return ((hostname=is_quad(is_quad(is_quad(is_quad(hostname))))) != NULL) &&
808 static int open_smtp_sink(struct query *ctl, struct msgblk *msg,
809 int *good_addresses, int *bad_addresses /* this must be signed, to prevent endless loop in from_addresses */)
810 /* open an SMTP stream */
814 char options[MSGBUFSIZE];
815 char addr[HOSTLEN+USERNAMELEN+1];
816 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
817 char **from_responses;
818 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
820 int force_transient_error = 0;
824 * Compute ESMTP options.
827 if (ctl->server.esmtp_options & ESMTP_8BITMIME) {
828 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
829 strcpy(options, " BODY=8BITMIME");
830 else if (ctl->mimemsg & MSG_IS_7BIT)
831 strcpy(options, " BODY=7BIT");
834 if ((ctl->server.esmtp_options & ESMTP_SIZE) && msg->reallen > 0)
835 sprintf(options + strlen(options), " SIZE=%d", msg->reallen);
838 * Try to get the SMTP listener to take the Return-Path
839 * address as MAIL FROM. If it won't, fall back on the
840 * remotename and mailserver host. This won't affect replies,
841 * which use the header From address anyway; the MAIL FROM
842 * address is a place for the SMTP listener to send
843 * bouncemail. The point is to guarantee a FQDN in the MAIL
844 * FROM line -- some SMTP listeners, like smail, become
847 * RFC 1123 requires that the domain name part of the
848 * MAIL FROM address be "canonicalized", that is a
849 * FQDN or MX but not a CNAME. We'll assume the Return-Path
850 * header is already in this form here (it certainly
851 * is if rewrite is on). RFC 1123 is silent on whether
852 * a nonexistent hostname part is considered canonical.
854 * This is a potential problem if the MTAs further upstream
855 * didn't pass canonicalized From/Return-Path lines, *and* the
856 * local SMTP listener insists on them.
858 * Handle the case where an upstream MTA is setting a return
859 * path equal to "@". Ghod knows why anyone does this, but
860 * it's been reported to happen in mail from Amazon.com and
863 * Also, if the hostname is a dotted quad, wrap it in square brackets.
864 * Apparently this is required by RFC2821, section 4.1.3.
866 if (!msg->return_path[0] || (msg->return_path[0] == '@'))
868 if (strchr(ctl->remotename,'@') || strchr(ctl->remotename,'!'))
870 snprintf(addr, sizeof(addr), "%s", ctl->remotename);
872 else if (is_dottedquad(ctl->server.truename))
874 snprintf(addr, sizeof(addr), "%s@[%s]", ctl->remotename,
875 ctl->server.truename);
879 snprintf(addr, sizeof(addr),
880 "%s@%s", ctl->remotename, ctl->server.truename);
884 else if (strchr(msg->return_path,'@') || strchr(msg->return_path,'!'))
885 ap = msg->return_path;
886 /* in case Return-Path was "<>" we want to preserve that */
887 else if (strcmp(msg->return_path,"<>") == 0)
888 ap = msg->return_path;
889 else /* in case Return-Path existed but was local */
891 if (is_dottedquad(ctl->server.truename))
893 snprintf(addr, sizeof(addr), "%s@[%s]", msg->return_path,
894 ctl->server.truename);
898 snprintf(addr, sizeof(addr), "%s@%s",
899 msg->return_path, ctl->server.truename);
904 if ((smtp_err = SMTP_from(ctl->smtp_socket, ctl->smtphostmode,
905 ap, options)) == SM_UNRECOVERABLE)
908 return(PS_TRANSIENT);
910 if (smtp_err != SM_OK)
912 int err = handle_smtp_report(ctl, msg); /* map to PS_TRANSIENT or PS_REFUSED */
914 smtp_rset(ctl); /* stay on the safe side */
919 * Now list the recipient addressees
922 for (idp = msg->recipients; idp; idp = idp->next)
924 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
925 from_responses = (char **)xmalloc(sizeof(char *) * total_addresses);
926 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
927 for (idp = msg->recipients; idp; idp = idp->next)
928 if (idp->val.status.mark == XMIT_ACCEPT)
931 address = rcpt_address (ctl, idp->id, 1);
932 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket, ctl->smtphostmode,
933 address)) == SM_UNRECOVERABLE)
937 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
938 while (*bad_addresses)
939 free(from_responses[--*bad_addresses]);
940 free(from_responses);
941 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
942 return(PS_TRANSIENT);
944 if (smtp_err == SM_OK)
948 switch (handle_smtp_report_without_bounce(ctl, msg))
951 force_transient_error = 1;
955 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
956 from_responses[*bad_addresses] = xstrdup(smtp_response);
957 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
960 idp->val.status.mark = XMIT_RCPTBAD;
961 if (outlevel >= O_VERBOSE)
963 GT_("%cMTP listener doesn't like recipient address `%s'\n"),
964 ctl->smtphostmode, address);
968 if (outlevel >= O_VERBOSE)
970 GT_("%cMTP listener doesn't really like recipient address `%s'\n"),
971 ctl->smtphostmode, address);
977 if (force_transient_error) {
978 /* do not risk dataloss due to overengineered multidrop
979 * crap. If one of the recipients returned PS_TRANSIENT,
980 * we return exactly that.
982 smtp_rset(ctl); /* required by RFC1870 */
985 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
987 * This should not be necessary, because the SMTP listener itself
988 * should generate a bounce for the bad address.
990 * XXX FIXME 2006-01-19: is this comment true? I don't think
991 * it is, because the SMTP listener isn't required to accept bogus
992 * messages. There appears to be general SMTP<->MDA and
993 * responsibility confusion.
996 send_bouncemail(ctl, msg, XMIT_RCPTBAD,
997 "Some addresses were rejected by the MDA fetchmail forwards to.\r\n",
998 *bad_addresses, from_responses);
999 while (*bad_addresses)
1000 free(from_responses[--*bad_addresses]);
1001 free(from_responses);
1002 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
1005 * It's tempting to do local notification only if bouncemail was
1006 * insufficient -- that is, to add && total_addresses > *bad_addresses
1007 * to the test here. The problem with this theory is that it would
1008 * make initial diagnosis of a broken multidrop configuration very
1009 * hard -- most single-recipient messages would just invisibly bounce.
1011 if (!(*good_addresses))
1013 if (!run.postmaster[0])
1015 if (outlevel >= O_VERBOSE)
1016 report(stderr, GT_("no address matches; no postmaster set.\n"));
1017 smtp_rset(ctl); /* required by RFC1870 */
1020 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket, ctl->smtphostmode,
1021 rcpt_address (ctl, run.postmaster, 0))) == SM_UNRECOVERABLE)
1024 return(PS_TRANSIENT);
1026 if (smtp_err != SM_OK)
1028 report(stderr, GT_("can't even send to %s!\n"), run.postmaster);
1029 smtp_rset(ctl); /* required by RFC1870 */
1033 if (outlevel >= O_VERBOSE)
1034 report(stderr, GT_("no address matches; forwarding to %s.\n"), run.postmaster);
1038 * Tell the listener we're ready to send data.
1039 * Some listeners (like zmailer) may return antispam errors here.
1041 if ((smtp_err = SMTP_data(ctl->smtp_socket, ctl->smtphostmode))
1042 == SM_UNRECOVERABLE)
1045 return(PS_TRANSIENT);
1047 if (smtp_err != SM_OK)
1049 int err = handle_smtp_report(ctl, msg);
1050 smtp_rset(ctl); /* stay on the safe side */
1055 * We need to stash this away in order to know how many
1056 * response lines to expect after the LMTP end-of-message.
1058 lmtp_responses = *good_addresses;
1063 static int open_mda_sink(struct query *ctl, struct msgblk *msg,
1064 int *good_addresses, int *bad_addresses)
1065 /* open a stream to a local MDA */
1069 int length = 0, fromlen = 0, nameslen = 0;
1070 char *names = NULL, *before, *after, *from = NULL;
1072 (void)bad_addresses;
1073 xfree(ctl->destaddr);
1074 ctl->destaddr = xstrdup("localhost");
1076 for (idp = msg->recipients; idp; idp = idp->next)
1077 if (idp->val.status.mark == XMIT_ACCEPT)
1078 (*good_addresses)++;
1080 length = strlen(ctl->mda);
1081 before = xstrdup(ctl->mda);
1083 /* get user addresses for %T (or %s for backward compatibility) */
1084 if (strstr(before, "%s") || strstr(before, "%T"))
1087 * We go through this in order to be able to handle very
1088 * long lists of users and (re)implement %s.
1091 for (idp = msg->recipients; idp; idp = idp->next)
1092 if (idp->val.status.mark == XMIT_ACCEPT)
1093 nameslen += (strlen(idp->id) + 1); /* string + ' ' */
1094 if (*good_addresses == 0)
1095 nameslen = strlen(run.postmaster);
1097 names = (char *)xmalloc(nameslen + 1); /* account for '\0' */
1098 if (*good_addresses == 0)
1099 strcpy(names, run.postmaster);
1103 for (idp = msg->recipients; idp; idp = idp->next)
1104 if (idp->val.status.mark == XMIT_ACCEPT)
1106 strcat(names, idp->id);
1109 names[--nameslen] = '\0'; /* chop trailing space */
1115 /* get From address for %F */
1116 if (strstr(before, "%F"))
1118 from = xstrdup(msg->return_path);
1122 fromlen = strlen(from);
1125 /* do we have to build an mda string? */
1130 /* find length of resulting mda string */
1132 while ((sp = strstr(sp, "%s"))) {
1133 length += nameslen; /* subtract %s and add '' */
1137 while ((sp = strstr(sp, "%T"))) {
1138 length += nameslen; /* subtract %T and add '' */
1142 while ((sp = strstr(sp, "%F"))) {
1143 length += fromlen; /* subtract %F and add '' */
1147 after = (char *)xmalloc(length + 1);
1149 /* copy mda source string to after, while expanding %[sTF] */
1150 for (dp = after, sp = before; (*dp = *sp); dp++, sp++) {
1151 if (sp[0] != '%') continue;
1153 if (sp > before && sp[-1] == '\'') {
1154 report(stderr, GT_("MDA option contains single-quoted %%%c expansion.\n"), sp[1]);
1155 report(stderr, GT_("Refusing to deliver. Check the manual and fix your mda option.\n"));
1158 if (from) free(from);
1159 if (names) free(names);
1163 /* need to expand? BTW, no here overflow, because in
1164 ** the worst case (end of string) sp[1] == '\0' */
1165 if (sp[1] == 's' || sp[1] == 'T') {
1170 sp++; /* position sp over [sT] */
1171 dp--; /* adjust dp */
1172 } else if (sp[1] == 'F') {
1177 sp++; /* position sp over F */
1178 dp--; /* adjust dp */
1197 if (outlevel >= O_DEBUG)
1198 report(stdout, GT_("about to deliver with: %s\n"), before);
1201 * Arrange to run with user's permissions if we're root.
1202 * This will initialize the ownership of any files the
1203 * MDA creates properly. (The seteuid call is available
1204 * under all BSDs and Linux)
1206 orig_uid = getuid();
1207 if (seteuid(ctl->uid)) {
1208 report(stderr, GT_("Cannot switch effective user id to %ld: %s\n"), (long)ctl->uid, strerror(errno));
1212 sinkfp = popen(before, "w");
1216 /* this will fail quietly if we didn't start as root */
1217 if (seteuid(orig_uid)) {
1218 report(stderr, GT_("Cannot switch effective user id back to original %ld: %s\n"), (long)orig_uid, strerror(errno));
1224 report(stderr, GT_("MDA open failed\n"));
1229 * We need to disable the normal SIGCHLD handling here because
1230 * sigchld_handler() would reap away the error status, returning
1231 * error status instead of 0 for successful completion.
1233 set_signal_handler(SIGCHLD, SIG_DFL);
1238 int open_sink(struct query *ctl, struct msgblk *msg,
1239 int *good_addresses, int *bad_addresses)
1240 /* set up sinkfp to be an input sink we can ship a message to */
1242 *bad_addresses = *good_addresses = 0;
1244 if (want_progress() && outlevel >= O_VERBOSE && !ctl->mda && !ctl->bsmtp) puts("");
1246 if (ctl->bsmtp) /* dump to a BSMTP batch file */
1247 return(open_bsmtp_sink(ctl, msg, good_addresses, bad_addresses));
1249 * Try to forward to an SMTP or LMTP listener. If the attempt to
1250 * open a socket fails, fall through to attempt delivery via
1253 else if (!ctl->mda && smtp_setup(ctl) != -1)
1254 return(open_smtp_sink(ctl, msg, good_addresses, bad_addresses));
1257 * Awkward case. User didn't specify an MDA. Our attempt to get a
1258 * listener socket failed. Try to cope anyway -- initial configuration
1259 * may have found procmail.
1263 report(stderr, GT_("%cMTP connect to %s failed\n"),
1265 ctl->smtphost ? ctl->smtphost : "localhost");
1267 #ifndef FALLBACK_MDA
1268 /* No fallback MDA declared. Bail out. */
1272 * If user had things set up to forward offsite, no way
1273 * we want to deliver locally!
1275 if (ctl->smtphost && strcmp(ctl->smtphost, "localhost"))
1279 * User was delivering locally. We have a fallback MDA.
1280 * Latch it in place, logging the error, and fall through.
1281 * Set stripcr as we would if MDA had been the initial transport
1283 ctl->mda = FALLBACK_MDA;
1285 ctl->stripcr = TRUE;
1287 report(stderr, GT_("can't raise the listener; falling back to %s"),
1292 if (ctl->mda) /* must deliver through an MDA */
1293 return(open_mda_sink(ctl, msg, good_addresses, bad_addresses));
1298 void release_sink(struct query *ctl)
1299 /* release the per-message output sink, whether it's a pipe or SMTP socket */
1301 if (ctl->bsmtp && sinkfp)
1303 if (strcmp(ctl->bsmtp, "-"))
1306 sinkfp = (FILE *)NULL;
1314 sinkfp = (FILE *)NULL;
1316 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1320 int close_sink(struct query *ctl, struct msgblk *msg, flag forward)
1321 /* perform end-of-message actions on the current output sink */
1325 if (want_progress() && outlevel >= O_VERBOSE && !ctl->mda && !ctl->bsmtp) puts("");
1327 if (ctl->bsmtp && sinkfp) {
1330 /* implicit disk-full check here... */
1331 fputs(".\r\n", sinkfp);
1332 error = ferror(sinkfp);
1334 if (strcmp(ctl->bsmtp, "-"))
1336 if (fclose(sinkfp) == EOF) {
1340 sinkfp = (FILE *)NULL;
1345 GT_("Message termination or close of BSMTP file failed: %s\n"), strerror(oerrno));
1348 } else if (ctl->mda) {
1349 int rc = 0, e = 0, e2 = 0, err = 0;
1351 /* close the delivery pipe, we'll reopen before next message */
1355 err = 1, e2 = errno;
1356 if ((fflush(sinkfp)))
1357 err = 1, e2 = errno;
1360 rc = pclose(sinkfp);
1362 sinkfp = (FILE *)NULL;
1365 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1370 report(stderr, GT_("Error writing to MDA: %s\n"), strerror(e2));
1371 } else if (WIFSIGNALED(rc)) {
1373 GT_("MDA died of signal %d\n"), WTERMSIG(rc));
1374 } else if (WIFEXITED(rc)) {
1376 GT_("MDA returned nonzero status %d\n"), WEXITSTATUS(rc));
1379 GT_("Strange: MDA pclose returned %d and errno %d/%s, cannot handle at %s:%d\n"),
1380 rc, e, strerror(e), __FILE__, __LINE__);
1388 /* write message terminator */
1389 if ((smtp_err = SMTP_eom(ctl->smtp_socket, ctl->smtphostmode))
1390 == SM_UNRECOVERABLE)
1395 if (smtp_err != SM_OK)
1397 if (handle_smtp_report(ctl, msg) != PS_REFUSED)
1399 smtp_rset(ctl); /* stay on the safe side */
1404 report(stderr, GT_("SMTP listener refused delivery\n"));
1405 smtp_rset(ctl); /* stay on the safe side */
1411 * If this is an SMTP connection, SMTP_eom() ate the response.
1412 * But could be this is an LMTP connection, in which case we have to
1413 * interpret either (a) a single 503 response meaning there
1414 * were no successful RCPT TOs, or (b) a variable number of
1415 * responses, one for each successful RCPT TO. We need to send
1416 * bouncemail on each failed response and then return TRUE anyway,
1417 * otherwise the message will get left in the queue and resent
1418 * to people who got it the first time.
1420 if (ctl->smtphostmode == LMTP_MODE)
1422 if (lmtp_responses == 0)
1424 SMTP_ok(ctl->smtp_socket, ctl->smtphostmode, TIMEOUT_EOM);
1427 * According to RFC2033, 503 is the only legal response
1428 * if no RCPT TO commands succeeded. No error recovery
1429 * is really possible here, as we have no idea what
1430 * insane thing the listener might be doing if it doesn't
1433 if (atoi(smtp_response) == 503)
1434 report(stderr, GT_("LMTP delivery error on EOM\n"));
1437 GT_("Unexpected non-503 response to LMTP EOM: %s\n"),
1441 * It's not completely clear what to do here. We choose to
1442 * interpret delivery failure here as a transient error,
1443 * the same way SMTP delivery failure is handled. If we're
1444 * wrong, an undead message will get stuck in the queue.
1450 int i, errors, rc = FALSE;
1453 /* eat the RFC2033-required responses, saving errors */
1454 responses = (char **)xmalloc(sizeof(char *) * lmtp_responses);
1455 for (errors = i = 0; i < lmtp_responses; i++)
1457 if ((smtp_err = SMTP_ok(ctl->smtp_socket, ctl->smtphostmode, TIMEOUT_EOM))
1458 == SM_UNRECOVERABLE)
1463 if (smtp_err != SM_OK)
1465 responses[errors] = xstrdup(smtp_response);
1471 rc = TRUE; /* all deliveries succeeded */
1474 * One or more deliveries failed.
1475 * If we can bounce a failures list back to the
1476 * sender, and the postmaster does not want to
1477 * deal with the bounces return TRUE, deleting the
1478 * message from the server so it won't be
1479 * re-forwarded on subsequent poll cycles.
1481 rc = send_bouncemail(ctl, msg, XMIT_ACCEPT,
1482 "LMTP partial delivery failure.\r\n",
1486 for (i = 0; i < errors; i++)
1497 int open_warning_by_mail(struct query *ctl)
1498 /* set up output sink for a mailed warning to calling user */
1503 * Dispatching warning email is a little complicated. The problem is
1504 * that we have to deal with three distinct cases:
1506 * 1. Single-drop running from user account. Warning mail should
1507 * go to the local name for which we're collecting (coincides
1508 * with calling user).
1510 * 2. Single-drop running from root or other privileged ID, with rc
1511 * file generated on the fly (Ken Estes's weird setup...) Mail
1512 * should go to the local name for which we're collecting (does not
1513 * coincide with calling user).
1515 * 3. Multidrop. Mail must go to postmaster. We leave the recipients
1516 * member null so this message will fall through to run.postmaster.
1518 * The zero in the reallen element means we won't pass a SIZE
1519 * option to ESMTP; the message length would be more trouble than
1520 * it's worth to compute.
1522 struct msgblk reply = {NULL, NULL, "FETCHMAIL-DAEMON@", 0, 0};
1525 strlcat(reply.return_path, ctl->smtpaddress ? ctl->smtpaddress :
1526 fetchmailhost, sizeof(reply.return_path));
1528 if (!MULTIDROP(ctl)) /* send to calling user */
1530 save_str(&reply.recipients, ctl->localnames->id, XMIT_ACCEPT);
1531 status = open_sink(ctl, &reply, &good, &bad);
1532 free_str_list(&reply.recipients);
1534 else /* send to postmaster */
1535 status = open_sink(ctl, &reply, &good, &bad);
1537 stuff_warning(NULL, ctl, "From: FETCHMAIL-DAEMON@%s",
1538 ctl->smtpaddress ? ctl->smtpaddress : fetchmailhost);
1539 stuff_warning(NULL, ctl, "Date: %s", rfc822timestamp());
1540 stuff_warning(NULL, ctl, "MIME-Version: 1.0");
1541 stuff_warning(NULL, ctl, "Content-Transfer-Encoding: 8bit");
1542 stuff_warning(NULL, ctl, "Content-Type: text/plain; charset=\"%s\"", iana_charset);
1547 /* format and ship a warning message line by mail */
1548 /* if rfc2047charset is non-NULL, encode the line (that is assumed to be
1549 * a header line) as per RFC-2047 using rfc2047charset as the character
1551 void stuff_warning(const char *rfc2047charset, struct query *ctl, const char *fmt, ... )
1553 /* make huge -- i18n can bulk up error messages a lot */
1554 char buf[2*MSGBUFSIZE+4];
1558 * stuffline() requires its input to be writeable (for CR stripping),
1559 * so we needed to copy the message to a writeable buffer anyway in
1560 * case it was a string constant. We make a virtue of that necessity
1561 * here by supporting stdargs/varargs.
1564 vsnprintf(buf, sizeof(buf) - 2, fmt, ap);
1567 snprintf(buf+strlen(buf), sizeof(buf)-strlen(buf), "\r\n");
1569 /* guard against very long lines */
1570 buf[MSGBUFSIZE+1] = '\r';
1571 buf[MSGBUFSIZE+2] = '\n';
1572 buf[MSGBUFSIZE+3] = '\0';
1574 stuffline(ctl, rfc2047charset != NULL ? rfc2047e(buf, rfc2047charset) : buf);
1577 void close_warning_by_mail(struct query *ctl, struct msgblk *msg)
1578 /* sign and send mailed warnings */
1580 stuff_warning(NULL, ctl, GT_("-- \nThe Fetchmail Daemon"));
1581 close_sink(ctl, msg, TRUE);
1584 void abort_message_sink(struct query *ctl)
1586 * Forcibly close the SMTP connection and re-open.
1588 * Used to abort message delivery once the DATA command has been issued.
1589 * Required because all text after the DATA command is considered to be
1590 * part of the message body (it is impossible to issue an SMTP command
1591 * to abort message delivery once the DATA command has been issued).
1598 /* sink.c ends here */