2 * sink.c -- forwarding/delivery support for fetchmail
4 * The interface of this module (open_sink(), stuff_line(), close_sink(),
5 * release_sink()) seals off the delivery logic from the protocol machine,
6 * so the latter won't have to care whether it's shipping to an [SL]MTP
7 * listener daemon or an MDA pipe.
9 * Copyright 1998 by Eric S. Raymond
10 * For license terms, see the file COPYING in this directory.
21 #endif /* HAVE_MEMORY_H */
22 #if defined(STDC_HEADERS)
25 #if defined(HAVE_UNISTD_H)
28 #if defined(HAVE_STDARG_H)
36 /* for W* macros after pclose() */
38 #include <sys/types.h>
40 #include <sys/resource.h>
44 #include "fetchmail.h"
49 /* BSD portability hack...I know, this is an ugly place to put it */
50 #if !defined(SIGCHLD) && defined(SIGCLD)
51 #define SIGCHLD SIGCLD
54 /* makes the open_sink()/close_sink() pair non-reentrant */
55 static int lmtp_responses;
57 void smtp_close(struct query *ctl, int sayquit)
58 /* close the socket to SMTP server */
60 if (ctl->smtp_socket != -1)
63 SMTP_quit(ctl->smtp_socket);
64 SockClose(ctl->smtp_socket);
65 ctl->smtp_socket = -1;
70 int smtp_open(struct query *ctl)
71 /* try to open a socket to the appropriate SMTP server for this query */
73 char *parsed_host = NULL;
75 /* maybe it's time to close the socket in order to force delivery */
76 if (NUM_NONZERO(ctl->batchlimit)) {
77 if (batchcount == ctl->batchlimit)
82 /* if no socket to any SMTP host is already set up, try to open one */
83 if (ctl->smtp_socket == -1)
86 * RFC 1123 requires that the domain name in HELO address is a
87 * "valid principal domain name" for the client host. If we're
88 * running in invisible mode, violate this with malice
89 * aforethought in order to make the Received headers and
92 * In fact this code relies on the RFC1123 requirement that the
93 * SMTP listener must accept messages even if verification of the
94 * HELO name fails (RFC1123 section 5.2.5, paragraph 2).
96 * How we compute the true mailhost name to pass to the
97 * listener doesn't affect behavior on RFC1123-violating
98 * listeners that check for name match; we're going to lose
99 * on those anyway because we can never give them a name
100 * that matches the local machine fetchmail is running on.
101 * What it will affect is the listener's logging.
104 const char *id_me = run.invisible ? ctl->server.truename : fetchmailhost;
105 int oldphase = phase;
110 * Run down the SMTP hunt list looking for a server that's up.
111 * Use both explicit hunt entries (value TRUE) and implicit
112 * (default) ones (value FALSE).
115 phase = LISTENER_WAIT;
117 set_timeout(ctl->server.timeout);
118 for (idp = ctl->smtphunt; idp; idp = idp->next)
122 char *portnum = SMTP_PORT;
124 int portnum = SMTP_PORT;
125 #endif /* INET6_ENABLE */
127 xalloca(parsed_host, char *, strlen(idp->id) + 1);
129 ctl->smtphost = idp->id; /* remember last host tried. */
130 if(ctl->smtphost[0]=='/')
131 ctl->listener = LMTP_MODE;
133 strcpy(parsed_host, idp->id);
134 if ((cp = strrchr(parsed_host, '/')))
141 #endif /* INET6_ENABLE */
144 if (ctl->smtphost[0]=='/'){
145 if ((ctl->smtp_socket = UnixOpen(ctl->smtphost))==-1)
148 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,NULL,
149 ctl->server.plugout)) == -1)
152 /* return immediately for ODMR */
153 if (ctl->server.protocol == P_ODMR)
157 return(ctl->smtp_socket); /* success */
160 /* are we doing SMTP or LMTP? */
161 SMTP_setmode(ctl->listener);
163 /* first, probe for ESMTP */
164 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
165 SMTP_ehlo(ctl->smtp_socket, id_me,
166 ctl->server.esmtp_name, ctl->server.esmtp_password,
167 &ctl->server.esmtp_options) == SM_OK)
171 * RFC 1869 warns that some listeners hang up on a failed EHLO,
172 * so it's safest not to assume the socket will still be good.
176 /* if opening for ESMTP failed, try SMTP */
177 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,NULL,
178 ctl->server.plugout)) == -1)
181 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
182 SMTP_helo(ctl->smtp_socket, id_me) == SM_OK)
192 * RFC 1123 requires that the domain name part of the
193 * RCPT TO address be "canonicalized", that is a FQDN
194 * or MX but not a CNAME. Some listeners (like exim)
195 * enforce this. Now that we have the actual hostname,
196 * compute what we should canonicalize with.
198 * make sure we do not forget to drop the /port if
201 if (ctl->listener == LMTP_MODE && !ctl->smtpaddress)
203 if (parsed_host && parsed_host[0] != 0)
204 ctl->destaddr = xstrdup(parsed_host);
206 ctl->destaddr = (ctl->smtphost && ctl->smtphost[0] != '/') ? ctl->smtphost : "localhost";
209 ctl->destaddr = ctl->smtpaddress ? ctl->smtpaddress : ( ctl->smtphost && ctl->smtphost[0] != '/' ? ctl->smtphost : "localhost");
211 if (outlevel >= O_DEBUG && ctl->smtp_socket != -1)
212 report(stdout, GT_("forwarding to %s\n"), ctl->smtphost);
214 return(ctl->smtp_socket);
217 static void sanitize(char *s)
218 /* replace unsafe shellchars by an _ */
220 const static char *ok_chars = " 1234567890!@%-_=+:,./abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
223 for (cp = s; *(cp += strspn(cp, ok_chars)); /* NO INCREMENT */)
227 char *rcpt_address(struct query *ctl, const char *id,
230 static char addr[HOSTLEN+USERNAMELEN+1];
234 snprintf(addr, sizeof (addr), "%s", id);
236 sprintf(addr, "%s", id);
237 #endif /* HAVE_SNPRINTF */
239 else if (usesmtpname && ctl->smtpname)
242 snprintf(addr, sizeof (addr), "%s", ctl->smtpname);
244 sprintf(addr, "%s", ctl->smtpname);
245 #endif /* HAVE_SNPRINTF */
250 snprintf(addr, sizeof (addr), "%s@%s", id, ctl->destaddr);
252 sprintf(addr, "%s@%s", id, ctl->destaddr);
253 #endif /* HAVE_SNPRINTF */
258 static int send_bouncemail(struct query *ctl, struct msgblk *msg,
259 int userclass, char *message,
260 int nerrors, char *errors[])
261 /* bounce back an error report a la RFC 1892 */
263 char daemon_name[18 + HOSTLEN] = "FETCHMAIL-DAEMON@";
264 char boundary[BUFSIZ], *bounce_to;
267 /* don't bounce in reply to undeliverable bounces */
268 if (!msg->return_path[0] || strcmp(msg->return_path, "<>") == 0)
271 bounce_to = (run.bouncemail ? msg->return_path : run.postmaster);
273 SMTP_setmode(SMTP_MODE);
275 /* can't just use fetchmailhost here, it might be localhost */
276 strcat(daemon_name, host_fqdn());
278 /* we need only SMTP for this purpose */
279 if ((sock = SockOpen("localhost", SMTP_PORT, NULL, NULL)) == -1)
282 if (SMTP_ok(sock) != SM_OK)
288 if (SMTP_helo(sock, fetchmailhost) != SM_OK
289 || SMTP_from(sock, daemon_name, (char *)NULL) != SM_OK
290 || SMTP_rcpt(sock, bounce_to) != SM_OK
291 || SMTP_data(sock) != SM_OK)
298 /* our first duty is to keep the sacred foo counters turning... */
300 snprintf(boundary, sizeof(boundary),
303 #endif /* HAVE_SNPRINTF */
304 "foo-mani-padme-hum-%d-%d-%ld",
305 (int)getpid(), (int)getppid(), time((time_t *)NULL));
307 if (outlevel >= O_VERBOSE)
308 report(stdout, GT_("SMTP: (bounce-message body)\n"));
310 /* this will usually go to sylog... */
311 report(stderr, GT_("mail from %s bounced to %s\n"),
312 daemon_name, bounce_to);
314 /* bouncemail headers */
315 SockPrintf(sock, "Return-Path: <>\r\n");
316 SockPrintf(sock, "From: %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 SockWrite(sock, message, strlen(message));
327 SockPrintf(sock, "\r\n");
328 SockPrintf(sock, "\r\n");
335 /* RFC1892 part 2 -- machine-readable responses */
336 SockPrintf(sock, "--%s\r\n", boundary);
337 SockPrintf(sock,"Content-Type: message/delivery-status\r\n");
338 SockPrintf(sock, "\r\n");
339 SockPrintf(sock, "Reporting-MTA: dns; %s\r\n", fetchmailhost);
342 for (idp = msg->recipients; idp; idp = idp->next)
343 if (idp->val.status.mark == userclass)
346 /* Minimum RFC1894 compliance + Diagnostic-Code field */
347 SockPrintf(sock, "\r\n");
348 SockPrintf(sock, "Final-Recipient: rfc822; %s\r\n",
349 rcpt_address (ctl, idp->id, 1));
350 SockPrintf(sock, "Last-Attempt-Date: %s\r\n", rfc822timestamp());
351 SockPrintf(sock, "Action: failed\r\n");
354 /* one error applies to all users */
356 else if (nerrors <= nusers)
358 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
362 /* errors correspond 1-1 to selected users */
363 error = errors[nusers++];
365 if (strlen(error) > 9 && isdigit(error[4])
366 && error[5] == '.' && isdigit(error[6])
367 && error[7] == '.' && isdigit(error[8]))
368 /* Enhanced status code available, use it */
369 SockPrintf(sock, "Status: %5.5s\r\n", &(error[4]));
371 /* Enhanced status code not available, fake one */
372 SockPrintf(sock, "Status: %c.0.0\r\n", error[0]);
373 SockPrintf(sock, "Diagnostic-Code: %s\r\n", error);
375 SockPrintf(sock, "\r\n");
378 /* RFC1892 part 3 -- headers of undelivered message */
379 SockPrintf(sock, "--%s\r\n", boundary);
380 SockPrintf(sock, "Content-Type: text/rfc822-headers\r\n");
381 SockPrintf(sock, "\r\n");
382 SockWrite(sock, msg->headers, strlen(msg->headers));
383 SockPrintf(sock, "\r\n");
384 SockPrintf(sock, "--%s--\r\n", boundary);
386 if (SMTP_eom(sock) != SM_OK || SMTP_quit(sock))
397 static int handle_smtp_report(struct query *ctl, struct msgblk *msg)
398 /* handle SMTP errors based on the content of SMTP_response */
399 /* return of PS_REFUSED deletes mail from the server; PS_TRANSIENT keeps it */
401 int smtperr = atoi(smtp_response);
404 xalloca(responses[0], char *, strlen(smtp_response)+1);
405 strcpy(responses[0], smtp_response);
409 * Don't do this! It can really mess you up if, for example, you're
410 * reporting an error with a single RCPT TO address among several;
411 * RSET discards the message body and it doesn't get sent to the
414 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
415 if (outlevel >= O_DEBUG)
416 report(stdout, GT_("Saved error is still %d\n"), smtperr);
417 #endif /* __UNUSED */
420 * Note: send_bouncemail message strings are not made subject
421 * to gettext translation because (a) they're going to be
422 * embedded in a text/plain 7bit part, and (b) they're
423 * going to be associated with listener error-response
424 * messages, which are probably in English (none of the
425 * MTAs I know about are internationalized).
427 if (str_find(&ctl->antispam, smtperr))
430 * SMTP listener explicitly refuses to deliver mail
431 * coming from this address, probably due to an
432 * anti-spam domain exclusion. Respect this. Don't
433 * try to ship the message, and don't prevent it from
434 * being deleted. There's no point in bouncing the
435 * email either since most spammers don't put their
436 * real return email address anywhere in the headers
437 * (unless the user insists with the SET SPAMBOUNCE
442 * 571 = sendmail's "unsolicited email refused"
443 * 550 = exim's new antispam response (temporary)
444 * 501 = exim's old antispam response
445 * 554 = Postfix antispam response.
452 snprintf(rejmsg, sizeof(rejmsg),
455 #endif /* HAVE_SNPRINTF */
456 "spam filter or virus scanner rejected message because:\r\n"
457 "%s\r\n", responses[0]);
459 send_bouncemail(ctl, msg, XMIT_ACCEPT,
460 rejmsg, 1, responses);
466 * Suppress error message only if the response specifically
467 * meant `excluded for policy reasons'. We *should* see
468 * an error when the return code is less specific.
471 report(stderr, GT_("%cMTP error: %s\n"),
477 case 552: /* message exceeds fixed maximum message size */
479 * Permanent no-go condition on the
480 * ESMTP server. Don't try to ship the message,
481 * and allow it to be deleted.
484 send_bouncemail(ctl, msg, XMIT_ACCEPT,
485 "This message was too large (SMTP error 552).\r\n",
489 case 553: /* invalid sending domain */
491 * These latter days 553 usually means a spammer is trying to
492 * cover his tracks. We never bouncemail on these, because
493 * (a) the return address is invalid by definition, and
494 * (b) we wouldn't want spammers to get confirmation that
495 * this address is live, anyway.
497 #ifdef __DONT_FEED_THE_SPAMMERS__
499 send_bouncemail(ctl, msg, XMIT_ACCEPT,
500 "Invalid address in MAIL FROM (SMTP error 553).\r\n",
502 #endif /* __DONT_FEED_THE_SPAMMERS__ */
506 /* bounce non-transient errors back to the sender */
507 if (smtperr >= 500 && smtperr <= 599)
508 if (send_bouncemail(ctl, msg, XMIT_ACCEPT,
509 "General SMTP/ESMTP error.\r\n",
511 return(run.bouncemail ? PS_REFUSED : PS_TRANSIENT);
513 * We're going to end up here on 4xx errors, like:
515 * 451: temporarily unable to identify sender (exim)
516 * 452: temporary out-of-queue-space condition on the ESMTP server.
518 * These are temporary errors. Don't try to ship the message,
519 * and suppress deletion so it can be retried on a future
522 * Bouncemail *might* be appropriate here as a delay
523 * notification (note; if we ever add this, we must make
524 * sure the RFC1894 Action field is "delayed" rather than
525 * "failed"). But it's not really necessary because
526 * these are not actual failures, we're very likely to be
527 * able to recover on the next cycle.
529 return(PS_TRANSIENT);
533 static int handle_smtp_report_without_bounce(struct query *ctl, struct msgblk *msg)
534 /* handle SMTP errors based on the content of SMTP_response */
535 /* atleast one PS_TRANSIENT: do not send the bounce mail, keep the mail;
536 * no PS_TRANSIENT, atleast one PS_SUCCESS: send the bounce mail, delete the mail;
537 * no PS_TRANSIENT, no PS_SUCCESS: do not send the bounce mail, delete the mail */
539 int smtperr = atoi(smtp_response);
541 if (str_find(&ctl->antispam, smtperr))
549 report(stderr, GT_("%cMTP error: %s\n"),
555 case 552: /* message exceeds fixed maximum message size */
560 case 553: /* invalid sending domain */
561 #ifdef __DONT_FEED_THE_SPAMMERS__
564 #endif /* __DONT_FEED_THE_SPAMMERS__ */
568 /* bounce non-transient errors back to the sender */
569 if (smtperr >= 500 && smtperr <= 599)
571 return(PS_TRANSIENT);
575 /* these are shared by open_sink and stuffline */
578 int stuffline(struct query *ctl, char *buf)
579 /* ship a line to the given control block's output sink (SMTP server or MDA) */
584 /* The line may contain NUL characters. Find the last char to use
585 * -- the real line termination is the sequence "\n\0".
588 while ((last += strlen(last)) && (last[-1] != '\n'))
591 /* fix message lines that have only \n termination (for qmail) */
594 if (last - 1 == buf || last[-2] != '\r')
603 phase = FORWARDING_WAIT;
606 * SMTP byte-stuffing. We only do this if the protocol does *not*
607 * use .<CR><LF> as EOM. If it does, the server will already have
608 * decorated any . lines it sends back up.
612 if (ctl->server.base_protocol->delimited) /* server has already byte-stuffed */
617 /* writing to SMTP, leave the byte-stuffing in place */;
619 else /* if (!protocol->delimited) -- not byte-stuffed already */
622 SockWrite(ctl->smtp_socket, buf, 1); /* byte-stuff it */
624 /* leave it alone */;
628 /* we may need to strip carriage returns */
633 for (sp = tp = buf; sp < last; sp++)
641 if (ctl->mda || ctl->bsmtp)
642 n = fwrite(buf, 1, last - buf, sinkfp);
643 else if (ctl->smtp_socket != -1)
644 n = SockWrite(ctl->smtp_socket, buf, last - buf);
651 static int open_bsmtp_sink(struct query *ctl, struct msgblk *msg,
652 int *good_addresses, int *bad_addresses)
653 /* open a BSMTP stream */
657 if (strcmp(ctl->bsmtp, "-") == 0)
660 sinkfp = fopen(ctl->bsmtp, "a");
662 /* see the ap computation under the SMTP branch */
664 "MAIL FROM: %s", (msg->return_path[0]) ? msg->return_path : user);
666 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
667 fputs(" BODY=8BITMIME", sinkfp);
668 else if (ctl->mimemsg & MSG_IS_7BIT)
669 fputs(" BODY=7BIT", sinkfp);
671 /* exim's BSMTP processor does not handle SIZE */
672 /* fprintf(sinkfp, " SIZE=%d", msg->reallen); */
674 fprintf(sinkfp, "\r\n");
677 * RFC 1123 requires that the domain name part of the
678 * RCPT TO address be "canonicalized", that is a FQDN
679 * or MX but not a CNAME. Some listeners (like exim)
680 * enforce this. Now that we have the actual hostname,
681 * compute what we should canonicalize with.
683 ctl->destaddr = ctl->smtpaddress ? ctl->smtpaddress : "localhost";
686 for (idp = msg->recipients; idp; idp = idp->next)
687 if (idp->val.status.mark == XMIT_ACCEPT)
689 fprintf(sinkfp, "RCPT TO: %s\r\n",
690 rcpt_address (ctl, idp->id, 1));
694 fputs("DATA\r\n", sinkfp);
698 report(stderr, GT_("BSMTP file open or preamble write failed\n"));
705 /* this is experimental and will be removed if double bounces are reported */
706 #define EXPLICIT_BOUNCE_ON_BAD_ADDRESS
709 static const char *is_quad(const char *q)
710 /* Check if the string passed in points to what could be one quad of a
711 * dotted-quad IP address. Requirements are that the string is not a
712 * NULL pointer, begins with a period (which is skipped) or a digit
713 * and ends with a period or a NULL. If these requirements are met, a
714 * pointer to the last character (the period or the NULL character) is
715 * returned; otherwise NULL.
724 for(r=q;isdigit(*r);r++)
726 if ( ((*r) && (*r != '.')) || ((r-q) < 1) || ((r-q)>3) )
728 /* Make sure quad is < 255 */
737 else if (*(q+1) == '5')
747 static int is_dottedquad(const char *hostname)
748 /* Returns a true value if the passed in string looks like an IP
749 * address in dotted-quad form, and a false value otherwise.
753 return ((hostname=is_quad(is_quad(is_quad(is_quad(hostname))))) != NULL) &&
757 static int open_smtp_sink(struct query *ctl, struct msgblk *msg,
758 int *good_addresses, int *bad_addresses)
759 /* open an SMTP stream */
763 char options[MSGBUFSIZE];
764 char addr[HOSTLEN+USERNAMELEN+1];
765 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
766 char **from_responses;
767 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
769 int force_transient_error = 0;
772 * Compute ESMTP options.
775 if (ctl->server.esmtp_options & ESMTP_8BITMIME) {
776 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
777 strcpy(options, " BODY=8BITMIME");
778 else if (ctl->mimemsg & MSG_IS_7BIT)
779 strcpy(options, " BODY=7BIT");
782 if ((ctl->server.esmtp_options & ESMTP_SIZE) && msg->reallen > 0)
783 sprintf(options + strlen(options), " SIZE=%d", msg->reallen);
786 * Try to get the SMTP listener to take the Return-Path
787 * address as MAIL FROM. If it won't, fall back on the
788 * remotename and mailserver host. This won't affect replies,
789 * which use the header From address anyway; the MAIL FROM
790 * address is a place for the SMTP listener to send
791 * bouncemail. The point is to guarantee a FQDN in the MAIL
792 * FROM line -- some SMTP listeners, like smail, become
795 * RFC 1123 requires that the domain name part of the
796 * MAIL FROM address be "canonicalized", that is a
797 * FQDN or MX but not a CNAME. We'll assume the Return-Path
798 * header is already in this form here (it certainly
799 * is if rewrite is on). RFC 1123 is silent on whether
800 * a nonexistent hostname part is considered canonical.
802 * This is a potential problem if the MTAs further upstream
803 * didn't pass canonicalized From/Return-Path lines, *and* the
804 * local SMTP listener insists on them.
806 * Handle the case where an upstream MTA is setting a return
807 * path equal to "@". Ghod knows why anyone does this, but
808 * it's been reported to happen in mail from Amazon.com and
811 * Also, if the hostname is a dotted quad, wrap it in square brackets.
812 * Apparently this is required by RFC2821, section 4.1.3.
814 if (!msg->return_path[0] || (msg->return_path[0] == '@'))
816 if (is_dottedquad(ctl->server.truename))
819 snprintf(addr, sizeof(addr),
822 #endif /* HAVE_SNPRINTF */
823 "%s@[%s]", ctl->remotename, ctl->server.truename);
828 snprintf(addr, sizeof(addr),
831 #endif /* HAVE_SNPRINTF */
832 "%s@%s", ctl->remotename, ctl->server.truename);
836 else if (strchr(msg->return_path,'@') || strchr(msg->return_path,'!'))
837 ap = msg->return_path;
838 else /* in case Return-Path existed but was local */
840 if (is_dottedquad(ctl->server.truename))
843 snprintf(addr, sizeof(addr),
846 #endif /* HAVE_SNPRINTF */
847 "%s@[%s]", msg->return_path, ctl->server.truename);
852 snprintf(addr, sizeof(addr),
855 #endif /* HAVE_SNPRINTF */
856 "%s@%s", msg->return_path, ctl->server.truename);
861 if (SMTP_from(ctl->smtp_socket, ap, options) != SM_OK)
863 int err = handle_smtp_report(ctl, msg);
865 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
870 * Now list the recipient addressees
873 for (idp = msg->recipients; idp; idp = idp->next)
875 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
876 xalloca(from_responses, char **, sizeof(char *) * total_addresses);
877 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
878 for (idp = msg->recipients; idp; idp = idp->next)
879 if (idp->val.status.mark == XMIT_ACCEPT)
882 address = rcpt_address (ctl, idp->id, 1);
883 if (SMTP_rcpt(ctl->smtp_socket, address) == SM_OK)
887 switch (handle_smtp_report_without_bounce(ctl, msg))
890 force_transient_error = 1;
894 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
895 xalloca(from_responses[*bad_addresses],
897 strlen(smtp_response)+1);
898 strcpy(from_responses[*bad_addresses], smtp_response);
899 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
902 idp->val.status.mark = XMIT_RCPTBAD;
903 if (outlevel >= O_VERBOSE)
905 GT_("%cMTP listener doesn't like recipient address `%s'\n"),
906 ctl->listener, address);
910 if (outlevel >= O_VERBOSE)
912 GT_("%cMTP listener doesn't really like recipient address `%s'\n"),
913 ctl->listener, address);
919 if (force_transient_error) {
920 /* do not risk dataloss due to overengineered multidrop
921 * crap. If one of the recipients returned PS_TRANSIENT,
922 * we return exactly that.
924 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
925 return(PS_TRANSIENT);
927 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
929 * This should not be necessary, because the SMTP listener itself
930 * should genrate a bounce for the bad address.
933 send_bouncemail(ctl, msg, XMIT_RCPTBAD,
934 "Some addresses were rejected by the MDA fetchmail forwards to.\r\n",
935 *bad_addresses, from_responses);
936 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
939 * It's tempting to do local notification only if bouncemail was
940 * insufficient -- that is, to add && total_addresses > *bad_addresses
941 * to the test here. The problem with this theory is that it would
942 * make initial diagnosis of a broken multidrop configuration very
943 * hard -- most single-recipient messages would just invisibly bounce.
945 if (!(*good_addresses))
947 if (!run.postmaster[0])
949 if (outlevel >= O_VERBOSE)
950 report(stderr, GT_("no address matches; no postmaster set.\n"));
951 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
954 if (SMTP_rcpt(ctl->smtp_socket,
955 rcpt_address (ctl, run.postmaster, 0)) != SM_OK)
957 report(stderr, GT_("can't even send to %s!\n"), run.postmaster);
958 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
962 if (outlevel >= O_VERBOSE)
963 report(stderr, GT_("no address matches; forwarding to %s.\n"), run.postmaster);
967 * Tell the listener we're ready to send data.
968 * Some listeners (like zmailer) may return antispam errors here.
970 if (SMTP_data(ctl->smtp_socket) != SM_OK)
972 int err = handle_smtp_report(ctl, msg);
973 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
978 * We need to stash this away in order to know how many
979 * response lines to expect after the LMTP end-of-message.
981 lmtp_responses = *good_addresses;
986 static int open_mda_sink(struct query *ctl, struct msgblk *msg,
987 int *good_addresses, int *bad_addresses)
988 /* open a stream to a local MDA */
990 #ifdef HAVE_SIGACTION
991 struct sigaction sa_new;
992 #endif /* HAVE_SIGACTION */
995 #endif /* HAVE_SETEUID */
997 int length = 0, fromlen = 0, nameslen = 0;
998 char *names = NULL, *before, *after, *from = NULL;
1000 ctl->destaddr = "localhost";
1002 for (idp = msg->recipients; idp; idp = idp->next)
1003 if (idp->val.status.mark == XMIT_ACCEPT)
1004 (*good_addresses)++;
1006 length = strlen(ctl->mda);
1007 before = xstrdup(ctl->mda);
1009 /* get user addresses for %T (or %s for backward compatibility) */
1010 if (strstr(before, "%s") || strstr(before, "%T"))
1013 * We go through this in order to be able to handle very
1014 * long lists of users and (re)implement %s.
1017 for (idp = msg->recipients; idp; idp = idp->next)
1018 if ((idp->val.status.mark == XMIT_ACCEPT))
1019 nameslen += (strlen(idp->id) + 1); /* string + ' ' */
1020 if ((*good_addresses == 0))
1021 nameslen = strlen(run.postmaster);
1023 names = (char *)xmalloc(nameslen + 1); /* account for '\0' */
1024 if (*good_addresses == 0)
1025 strcpy(names, run.postmaster);
1029 for (idp = msg->recipients; idp; idp = idp->next)
1030 if (idp->val.status.mark == XMIT_ACCEPT)
1032 strcat(names, idp->id);
1035 names[--nameslen] = '\0'; /* chop trailing space */
1038 /* sanitize names in order to contain only harmless shell chars */
1042 /* get From address for %F */
1043 if (strstr(before, "%F"))
1045 from = xstrdup(msg->return_path);
1047 /* sanitize from in order to contain *only* harmless shell chars */
1050 fromlen = strlen(from);
1053 /* do we have to build an mda string? */
1058 /* find length of resulting mda string */
1060 while ((sp = strstr(sp, "%s"))) {
1061 length += nameslen - 2; /* subtract %s */
1065 while ((sp = strstr(sp, "%T"))) {
1066 length += nameslen - 2; /* subtract %T */
1070 while ((sp = strstr(sp, "%F"))) {
1071 length += fromlen - 2; /* subtract %F */
1075 after = xmalloc(length + 1);
1077 /* copy mda source string to after, while expanding %[sTF] */
1078 for (dp = after, sp = before; (*dp = *sp); dp++, sp++) {
1079 if (sp[0] != '%') continue;
1081 /* need to expand? BTW, no here overflow, because in
1082 ** the worst case (end of string) sp[1] == '\0' */
1083 if (sp[1] == 's' || sp[1] == 'T') {
1086 sp++; /* position sp over [sT] */
1087 dp--; /* adjust dp */
1088 } else if (sp[1] == 'F') {
1091 sp++; /* position sp over F */
1092 dp--; /* adjust dp */
1111 if (outlevel >= O_DEBUG)
1112 report(stdout, GT_("about to deliver with: %s\n"), before);
1116 * Arrange to run with user's permissions if we're root.
1117 * This will initialize the ownership of any files the
1118 * MDA creates properly. (The seteuid call is available
1119 * under all BSDs and Linux)
1121 orig_uid = getuid();
1123 #endif /* HAVE_SETEUID */
1125 sinkfp = popen(before, "w");
1130 /* this will fail quietly if we didn't start as root */
1132 #endif /* HAVE_SETEUID */
1136 report(stderr, GT_("MDA open failed\n"));
1141 * We need to disable the normal SIGCHLD handling here because
1142 * sigchld_handler() would reap away the error status, returning
1143 * error status instead of 0 for successful completion.
1145 #ifndef HAVE_SIGACTION
1146 signal(SIGCHLD, SIG_DFL);
1148 memset (&sa_new, 0, sizeof sa_new);
1149 sigemptyset (&sa_new.sa_mask);
1150 sa_new.sa_handler = SIG_DFL;
1151 sigaction (SIGCHLD, &sa_new, NULL);
1152 #endif /* HAVE_SIGACTION */
1157 int open_sink(struct query *ctl, struct msgblk *msg,
1158 int *good_addresses, int *bad_addresses)
1159 /* set up sinkfp to be an input sink we can ship a message to */
1161 *bad_addresses = *good_addresses = 0;
1163 if (ctl->bsmtp) /* dump to a BSMTP batch file */
1164 return(open_bsmtp_sink(ctl, msg, good_addresses, bad_addresses));
1166 * Try to forward to an SMTP or LMTP listener. If the attempt to
1167 * open a socket fails, fall through to attempt delivery via
1170 else if (!ctl->mda && smtp_open(ctl) != -1)
1171 return(open_smtp_sink(ctl, msg, good_addresses, bad_addresses));
1174 * Awkward case. User didn't specify an MDA. Our attempt to get a
1175 * listener socket failed. Try to cope anyway -- initial configuration
1176 * may have found procmail.
1180 report(stderr, GT_("%cMTP connect to %s failed\n"),
1182 ctl->smtphost ? ctl->smtphost : "localhost");
1184 #ifndef FALLBACK_MDA
1185 /* No fallback MDA declared. Bail out. */
1189 * If user had things set up to forward offsite, no way
1190 * we want to deliver locally!
1192 if (ctl->smtphost && strcmp(ctl->smtphost, "localhost"))
1196 * User was delivering locally. We have a fallback MDA.
1197 * Latch it in place, logging the error, and fall through.
1198 * Set stripcr as we would if MDA had been the initial transport
1200 ctl->mda = FALLBACK_MDA;
1202 ctl->stripcr = TRUE;
1204 report(stderr, GT_("can't raise the listener; falling back to %s"),
1209 if (ctl->mda) /* must deliver through an MDA */
1210 return(open_mda_sink(ctl, msg, good_addresses, bad_addresses));
1215 void release_sink(struct query *ctl)
1216 /* release the per-message output sink, whether it's a pipe or SMTP socket */
1218 if (ctl->bsmtp && sinkfp)
1220 if (strcmp(ctl->bsmtp, "-"))
1223 sinkfp = (FILE *)NULL;
1231 sinkfp = (FILE *)NULL;
1233 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1237 int close_sink(struct query *ctl, struct msgblk *msg, flag forward)
1238 /* perform end-of-message actions on the current output sink */
1244 /* close the delivery pipe, we'll reopen before next message */
1247 rc = pclose(sinkfp);
1248 sinkfp = (FILE *)NULL;
1253 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1257 if (WIFSIGNALED(rc)) {
1259 GT_("MDA died of signal %d\n"), WTERMSIG(rc));
1260 } else if (WIFEXITED(rc)) {
1262 GT_("MDA returned nonzero status %d\n"), WEXITSTATUS(rc));
1265 GT_("Strange: MDA pclose returned %d, cannot handle at %s:%d\n"), rc, __FILE__, __LINE__);
1271 else if (ctl->bsmtp && sinkfp)
1275 /* implicit disk-full check here... */
1276 fputs(".\r\n", sinkfp);
1277 error = ferror(sinkfp);
1278 if (strcmp(ctl->bsmtp, "-"))
1280 if (fclose(sinkfp) == EOF) error = 1;
1281 sinkfp = (FILE *)NULL;
1286 GT_("Message termination or close of BSMTP file failed\n"));
1292 /* write message terminator */
1293 if (SMTP_eom(ctl->smtp_socket) != SM_OK)
1295 if (handle_smtp_report(ctl, msg) != PS_REFUSED)
1297 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1302 report(stderr, GT_("SMTP listener refused delivery\n"));
1303 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1309 * If this is an SMTP connection, SMTP_eom() ate the response.
1310 * But could be this is an LMTP connection, in which case we have to
1311 * interpret either (a) a single 503 response meaning there
1312 * were no successful RCPT TOs, or (b) a variable number of
1313 * responses, one for each successful RCPT TO. We need to send
1314 * bouncemail on each failed response and then return TRUE anyway,
1315 * otherwise the message will get left in the queue and resent
1316 * to people who got it the first time.
1318 if (ctl->listener == LMTP_MODE)
1320 if (lmtp_responses == 0)
1322 SMTP_ok(ctl->smtp_socket);
1325 * According to RFC2033, 503 is the only legal response
1326 * if no RCPT TO commands succeeded. No error recovery
1327 * is really possible here, as we have no idea what
1328 * insane thing the listener might be doing if it doesn't
1331 if (atoi(smtp_response) == 503)
1332 report(stderr, GT_("LMTP delivery error on EOM\n"));
1335 GT_("Unexpected non-503 response to LMTP EOM: %s\n"),
1339 * It's not completely clear what to do here. We choose to
1340 * interpret delivery failure here as a transient error,
1341 * the same way SMTP delivery failure is handled. If we're
1342 * wrong, an undead message will get stuck in the queue.
1351 /* eat the RFC2033-required responses, saving errors */
1352 xalloca(responses, char **, sizeof(char *) * lmtp_responses);
1353 for (errors = i = 0; i < lmtp_responses; i++)
1355 if (SMTP_ok(ctl->smtp_socket) == SM_OK)
1356 responses[i] = (char *)NULL;
1359 xalloca(responses[errors],
1361 strlen(smtp_response)+1);
1362 strcpy(responses[errors], smtp_response);
1368 return(TRUE); /* all deliveries succeeded */
1371 * One or more deliveries failed.
1372 * If we can bounce a failures list back to the
1373 * sender, and the postmaster does not want to
1374 * deal with the bounces return TRUE, deleting the
1375 * message from the server so it won't be
1376 * re-forwarded on subsequent poll cycles.
1378 return(send_bouncemail(ctl, msg, XMIT_ACCEPT,
1379 "LSMTP partial delivery failure.\r\n",
1380 errors, responses));
1388 int open_warning_by_mail(struct query *ctl, struct msgblk *msg)
1389 /* set up output sink for a mailed warning to calling user */
1394 * Dispatching warning email is a little complicated. The problem is
1395 * that we have to deal with three distinct cases:
1397 * 1. Single-drop running from user account. Warning mail should
1398 * go to the local name for which we're collecting (coincides
1399 * with calling user).
1401 * 2. Single-drop running from root or other privileged ID, with rc
1402 * file generated on the fly (Ken Estes's weird setup...) Mail
1403 * should go to the local name for which we're collecting (does not
1404 * coincide with calling user).
1406 * 3. Multidrop. Mail must go to postmaster. We leave the recipients
1407 * member null so this message will fall through to run.postmaster.
1409 * The zero in the reallen element means we won't pass a SIZE
1410 * option to ESMTP; the message length would be more trouble than
1411 * it's worth to compute.
1413 struct msgblk reply = {NULL, NULL, "FETCHMAIL-DAEMON@", 0};
1416 strcat(reply.return_path, ctl->smtpaddress ? ctl->smtpaddress :
1419 if (!MULTIDROP(ctl)) /* send to calling user */
1421 save_str(&reply.recipients, ctl->localnames->id, XMIT_ACCEPT);
1422 status = open_sink(ctl, &reply, &good, &bad);
1423 free_str_list(&reply.recipients);
1425 else /* send to postmaster */
1426 status = open_sink(ctl, &reply, &good, &bad);
1427 stuff_warning(ctl, "Date: %s", rfc822timestamp());
1431 #if defined(HAVE_STDARG_H)
1432 void stuff_warning(struct query *ctl, const char *fmt, ... )
1434 void stuff_warning(struct query *ctl, fmt, va_alist)
1436 const char *fmt; /* printf-style format */
1439 /* format and ship a warning message line by mail */
1441 char buf[POPBUFSIZE];
1445 * stuffline() requires its input to be writeable (for CR stripping),
1446 * so we needed to copy the message to a writeable buffer anyway in
1447 * case it was a string constant. We make a virtue of that necessity
1448 * here by supporting stdargs/varargs.
1450 #if defined(HAVE_STDARG_H)
1455 #ifdef HAVE_VSNPRINTF
1456 vsnprintf(buf, sizeof(buf), fmt, ap);
1458 vsprintf(buf, fmt, ap);
1462 #ifdef HAVE_SNPRINTF
1463 snprintf(buf+strlen(buf), sizeof(buf)-strlen(buf), "\r\n");
1465 strcat(buf, "\r\n");
1466 #endif /* HAVE_SNPRINTF */
1468 stuffline(ctl, buf);
1471 void close_warning_by_mail(struct query *ctl, struct msgblk *msg)
1472 /* sign and send mailed warnings */
1474 stuff_warning(ctl, GT_("--\n\t\t\t\tThe Fetchmail Daemon\n"));
1475 close_sink(ctl, msg, TRUE);
1478 /* sink.c ends here */