2 * sink.c -- forwarding/delivery support for fetchmail
4 * The interface of this module (open_sink(), stuff_line(), close_sink(),
5 * release_sink()) seals off the delivery logic from the protocol machine,
6 * so the latter won't have to care whether it's shipping to an [SL]MTP
7 * listener daemon or an MDA pipe.
9 * Copyright 1998 by Eric S. Raymond
10 * For license terms, see the file COPYING in this directory.
20 #endif /* HAVE_MEMORY_H */
21 #if defined(STDC_HEADERS)
24 #if defined(HAVE_UNISTD_H)
27 #if defined(HAVE_STDARG_H)
35 /* for W* macros after pclose() */
37 #include <sys/types.h>
38 #include <sys/resource.h>
42 #include "fetchmail.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);
62 SockClose(ctl->smtp_socket);
63 ctl->smtp_socket = -1;
68 int smtp_open(struct query *ctl)
69 /* try to open a socket to the appropriate SMTP server for this query */
71 char *parsed_host = NULL;
73 /* maybe it's time to close the socket in order to force delivery */
74 if (last_smtp_ok > 0 && time((time_t *)NULL) - last_smtp_ok > mytimeout)
79 if (NUM_NONZERO(ctl->batchlimit)) {
80 if (batchcount == ctl->batchlimit)
85 /* if no socket to any SMTP host is already set up, try to open one */
86 if (ctl->smtp_socket == -1)
89 * RFC 1123 requires that the domain name in HELO address is a
90 * "valid principal domain name" for the client host. If we're
91 * running in invisible mode, violate this with malice
92 * aforethought in order to make the Received headers and
95 * In fact this code relies on the RFC1123 requirement that the
96 * SMTP listener must accept messages even if verification of the
97 * HELO name fails (RFC1123 section 5.2.5, paragraph 2).
99 * How we compute the true mailhost name to pass to the
100 * listener doesn't affect behavior on RFC1123-violating
101 * listeners that check for name match; we're going to lose
102 * on those anyway because we can never give them a name
103 * that matches the local machine fetchmail is running on.
104 * What it will affect is the listener's logging.
107 const char *id_me = run.invisible ? ctl->server.truename : fetchmailhost;
108 int oldphase = phase;
113 * Run down the SMTP hunt list looking for a server that's up.
114 * Use both explicit hunt entries (value TRUE) and implicit
115 * (default) ones (value FALSE).
118 phase = LISTENER_WAIT;
120 set_timeout(ctl->server.timeout);
121 for (idp = ctl->smtphunt; idp; idp = idp->next)
125 char *portnum = SMTP_PORT;
127 int portnum = SMTP_PORT;
128 #endif /* INET6_ENABLE */
130 xalloca(parsed_host, char *, strlen(idp->id) + 1);
132 ctl->smtphost = idp->id; /* remember last host tried. */
133 if(ctl->smtphost[0]=='/')
134 ctl->listener = LMTP_MODE;
136 strcpy(parsed_host, idp->id);
137 if ((cp = strrchr(parsed_host, '/')))
144 #endif /* INET6_ENABLE */
147 if (ctl->smtphost[0]=='/'){
148 if ((ctl->smtp_socket = UnixOpen(ctl->smtphost))==-1)
151 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,NULL,
152 ctl->server.plugout)) == -1)
155 /* return immediately for ODMR */
156 if (ctl->server.protocol == P_ODMR)
160 return(ctl->smtp_socket); /* success */
163 /* are we doing SMTP or LMTP? */
164 SMTP_setmode(ctl->listener);
166 /* first, probe for ESMTP */
167 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
168 SMTP_ehlo(ctl->smtp_socket, id_me,
169 ctl->server.esmtp_name, ctl->server.esmtp_password,
170 &ctl->server.esmtp_options) == SM_OK)
174 * RFC 1869 warns that some listeners hang up on a failed EHLO,
175 * so it's safest not to assume the socket will still be good.
179 /* if opening for ESMTP failed, try SMTP */
180 if ((ctl->smtp_socket = SockOpen(parsed_host,portnum,NULL,
181 ctl->server.plugout)) == -1)
184 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
185 SMTP_helo(ctl->smtp_socket, id_me) == SM_OK)
195 * RFC 1123 requires that the domain name part of the
196 * RCPT TO address be "canonicalized", that is a FQDN
197 * or MX but not a CNAME. Some listeners (like exim)
198 * enforce this. Now that we have the actual hostname,
199 * compute what we should canonicalize with.
201 * make sure we do not forget to drop the /port if
204 if (ctl->listener == LMTP_MODE && !ctl->smtpaddress)
206 if (parsed_host && parsed_host[0] != 0)
207 ctl->destaddr = xstrdup(parsed_host);
209 ctl->destaddr = (ctl->smtphost && ctl->smtphost[0] != '/') ? ctl->smtphost : "localhost";
214 * Here we try to find a correct domain name part for the RCPT
215 * TO address. If smtpaddress is set, no need to guestimate
216 * it. Otherwise, using ctl->smtphost as a base is a good
217 * base, although we may have to strip any port appended to
218 * communicate with SMTP servers that do not listen on the
219 * SMTP port. (benj) */
220 if (ctl->smtpaddress)
221 ctl->destaddr = ctl->smtpaddress;
222 else if (ctl->smtphost && ctl->smtphost[0] != '/')
225 if ((cp = strchr (ctl->smtphost, '/')))
227 /* As an alternate port for smtphost is specified, we
228 need to strip it from domain name. */
230 xalloca(smtpname, char *, cp - ctl->smtphost + 1);
231 strncpy(smtpname, ctl->smtphost, cp - ctl->smtphost +1);
232 cp = strchr(smtpname, '/');
234 ctl->destaddr = smtpname;
237 /* No need to strip port, domain name is smtphost. */
238 ctl->destaddr = ctl->smtphost;
240 /* No smtphost is specified or it is a UNIX socket, then use
241 localhost as a domain part. */
243 ctl->destaddr = "localhost";
246 if (outlevel >= O_DEBUG && ctl->smtp_socket != -1)
247 report(stdout, GT_("forwarding to %s\n"), ctl->smtphost);
249 return(ctl->smtp_socket);
252 static void sanitize(char *s)
257 for (cp = s; (cp = strchr (cp, '\'')); cp++)
261 char *rcpt_address(struct query *ctl, const char *id,
264 static char addr[HOSTLEN+USERNAMELEN+1];
267 snprintf(addr, sizeof (addr), "%s", id);
269 else if (usesmtpname && ctl->smtpname)
271 snprintf(addr, sizeof (addr), "%s", ctl->smtpname);
275 snprintf(addr, sizeof (addr), "%s@%s", id, ctl->destaddr);
280 static int send_bouncemail(struct query *ctl, struct msgblk *msg,
281 int userclass, char *message,
282 int nerrors, char *errors[])
283 /* bounce back an error report a la RFC 1892 */
285 char daemon_name[15 + HOSTLEN] = "MAILER-DAEMON@";
286 char boundary[BUFSIZ], *bounce_to;
288 static char *fqdn_of_host = NULL;
289 const char *md1 = "MAILER-DAEMON", *md2 = "MAILER-DAEMON@";
291 /* don't bounce in reply to undeliverable bounces */
292 if (!msg->return_path[0] ||
293 strcmp(msg->return_path, "<>") == 0 ||
294 strcasecmp(msg->return_path, md1) == 0 ||
295 strncasecmp(msg->return_path, md2, strlen(md2)) == 0)
298 bounce_to = (run.bouncemail ? msg->return_path : run.postmaster);
300 SMTP_setmode(SMTP_MODE);
302 /* can't just use fetchmailhost here, it might be localhost */
303 if (fqdn_of_host == NULL)
304 fqdn_of_host = host_fqdn();
305 strcat(daemon_name, fqdn_of_host);
307 /* we need only SMTP for this purpose */
308 if ((sock = SockOpen("localhost", SMTP_PORT, NULL, NULL)) == -1)
311 if (SMTP_ok(sock) != SM_OK)
317 if (SMTP_helo(sock, fetchmailhost) != SM_OK
318 || SMTP_from(sock, "<>", (char *)NULL) != SM_OK
319 || SMTP_rcpt(sock, bounce_to) != SM_OK
320 || SMTP_data(sock) != SM_OK)
327 /* our first duty is to keep the sacred foo counters turning... */
328 snprintf(boundary, sizeof(boundary), "foo-mani-padme-hum-%ld-%ld-%ld",
329 (long)getpid(), (long)getppid(), time(NULL));
331 if (outlevel >= O_VERBOSE)
332 report(stdout, GT_("SMTP: (bounce-message body)\n"));
334 /* this will usually go to sylog... */
335 report(stderr, GT_("mail from %s bounced to %s\n"),
336 daemon_name, bounce_to);
339 /* bouncemail headers */
340 SockPrintf(sock, "Subject: Mail delivery failed: returning message to sender\r\n");
341 SockPrintf(sock, "From: Mail Delivery System <%s>\r\n", daemon_name);
342 SockPrintf(sock, "To: %s\r\n", bounce_to);
343 SockPrintf(sock, "MIME-Version: 1.0\r\n");
344 SockPrintf(sock, "Content-Type: multipart/report; report-type=delivery-status;\r\n\tboundary=\"%s\"\r\n", boundary);
345 SockPrintf(sock, "\r\n");
347 /* RFC1892 part 1 -- human-readable message */
348 SockPrintf(sock, "--%s\r\n", boundary);
349 SockPrintf(sock,"Content-Type: text/plain\r\n");
350 SockPrintf(sock, "\r\n");
351 SockPrintf(sock, "This message was created automatically by mail delivery software.\r\n\r\n");
352 SockPrintf(sock, "A message that you sent could not be delivered to one or more of its\r\n");
353 SockPrintf(sock, "recipients. This is a permanent error. The following address(es) failed:\r\n");
354 SockPrintf(sock, "\r\n");
362 for (idp = msg->recipients; idp; idp = idp->next)
364 if (idp->val.status.mark == userclass)
367 SockPrintf(sock, "%s\r\n", rcpt_address (ctl, idp->id, 1));
369 if (nerrors == 1) error = errors[0];
370 else if (nerrors <= nusers)
372 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
375 else error = errors[nusers++];
377 SockPrintf(sock, " SMTP error: %s\r\n\r\n", error);
381 /* RFC1892 part 2 -- machine-readable responses */
382 SockPrintf(sock, "--%s\r\n", boundary);
383 SockPrintf(sock,"Content-Type: message/delivery-status\r\n");
384 SockPrintf(sock, "\r\n");
385 SockPrintf(sock, "Reporting-MTA: dns; %s\r\n", fqdn_of_host);
388 for (idp = msg->recipients; idp; idp = idp->next)
389 if (idp->val.status.mark == userclass)
392 /* Minimum RFC1894 compliance + Diagnostic-Code field */
393 SockPrintf(sock, "\r\n");
394 SockPrintf(sock, "Final-Recipient: rfc822; %s\r\n",
395 rcpt_address (ctl, idp->id, 1));
396 SockPrintf(sock, "Last-Attempt-Date: %s\r\n", rfc822timestamp());
397 SockPrintf(sock, "Action: failed\r\n");
400 /* one error applies to all users */
402 else if (nerrors <= nusers)
404 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
408 /* errors correspond 1-1 to selected users */
409 error = errors[nusers++];
411 if (strlen(error) > 9 && isdigit((unsigned char)error[4])
412 && error[5] == '.' && isdigit((unsigned char)error[6])
413 && error[7] == '.' && isdigit((unsigned char)error[8]))
414 /* Enhanced status code available, use it */
415 SockPrintf(sock, "Status: %5.5s\r\n", &(error[4]));
417 /* Enhanced status code not available, fake one */
418 SockPrintf(sock, "Status: %c.0.0\r\n", error[0]);
419 SockPrintf(sock, "Diagnostic-Code: %s\r\n", error);
421 SockPrintf(sock, "\r\n");
424 /* RFC1892 part 3 -- headers of undelivered message */
425 SockPrintf(sock, "--%s\r\n", boundary);
426 SockPrintf(sock, "Content-Type: text/rfc822-headers\r\n");
427 SockPrintf(sock, "\r\n");
430 SockWrite(sock, msg->headers, strlen(msg->headers));
431 SockPrintf(sock, "\r\n");
433 SockPrintf(sock, "--%s--\r\n", boundary);
435 if (SMTP_eom(sock) != SM_OK || SMTP_quit(sock))
446 static int handle_smtp_report(struct query *ctl, struct msgblk *msg)
447 /* handle SMTP errors based on the content of SMTP_response */
448 /* return of PS_REFUSED deletes mail from the server; PS_TRANSIENT keeps it */
450 int smtperr = atoi(smtp_response);
455 xalloca(responses[0], char *, strlen(smtp_response)+1);
456 strcpy(responses[0], smtp_response);
460 * Don't do this! It can really mess you up if, for example, you're
461 * reporting an error with a single RCPT TO address among several;
462 * RSET discards the message body and it doesn't get sent to the
465 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
466 if (outlevel >= O_DEBUG)
467 report(stdout, GT_("Saved error is still %d\n"), smtperr);
468 #endif /* __UNUSED */
471 * Note: send_bouncemail message strings are not made subject
472 * to gettext translation because (a) they're going to be
473 * embedded in a text/plain 7bit part, and (b) they're
474 * going to be associated with listener error-response
475 * messages, which are probably in English (none of the
476 * MTAs I know about are internationalized).
478 for( walk = ctl->antispam; walk; walk = walk->next )
479 if ( walk->val.status.num == smtperr )
485 /* if (str_find(&ctl->antispam, smtperr)) */
489 * SMTP listener explicitly refuses to deliver mail
490 * coming from this address, probably due to an
491 * anti-spam domain exclusion. Respect this. Don't
492 * try to ship the message, and don't prevent it from
493 * being deleted. There's no point in bouncing the
494 * email either since most spammers don't put their
495 * real return email address anywhere in the headers
496 * (unless the user insists with the SET SPAMBOUNCE
501 * 571 = sendmail's "unsolicited email refused"
502 * 550 = exim's new antispam response (temporary)
503 * 501 = exim's old antispam response
504 * 554 = Postfix antispam response.
510 snprintf(rejmsg, sizeof(rejmsg),
511 "spam filter or virus scanner rejected message because:\r\n"
512 "%s\r\n", responses[0]);
514 send_bouncemail(ctl, msg, XMIT_ACCEPT,
515 rejmsg, 1, responses);
521 * Suppress error message only if the response specifically
522 * meant `excluded for policy reasons'. We *should* see
523 * an error when the return code is less specific.
526 report(stderr, GT_("%cMTP error: %s\n"),
532 case 552: /* message exceeds fixed maximum message size */
534 * Permanent no-go condition on the
535 * ESMTP server. Don't try to ship the message,
536 * and allow it to be deleted.
539 send_bouncemail(ctl, msg, XMIT_ACCEPT,
540 "This message was too large (SMTP error 552).\r\n",
544 case 553: /* invalid sending domain */
546 * These latter days 553 usually means a spammer is trying to
547 * cover his tracks. We never bouncemail on these, because
548 * (a) the return address is invalid by definition, and
549 * (b) we wouldn't want spammers to get confirmation that
550 * this address is live, anyway.
552 #ifdef __DONT_FEED_THE_SPAMMERS__
554 send_bouncemail(ctl, msg, XMIT_ACCEPT,
555 "Invalid address in MAIL FROM (SMTP error 553).\r\n",
557 #endif /* __DONT_FEED_THE_SPAMMERS__ */
561 /* bounce non-transient errors back to the sender */
562 if (smtperr >= 500 && smtperr <= 599)
564 send_bouncemail(ctl, msg, XMIT_ACCEPT,
565 "General SMTP/ESMTP error.\r\n",
570 * We're going to end up here on 4xx errors, like:
572 * 451: temporarily unable to identify sender (exim)
573 * 452: temporary out-of-queue-space condition on the ESMTP server.
575 * These are temporary errors. Don't try to ship the message,
576 * and suppress deletion so it can be retried on a future
579 * Bouncemail *might* be appropriate here as a delay
580 * notification (note; if we ever add this, we must make
581 * sure the RFC1894 Action field is "delayed" rather than
582 * "failed"). But it's not really necessary because
583 * these are not actual failures, we're very likely to be
584 * able to recover on the next cycle.
586 return(PS_TRANSIENT);
590 static int handle_smtp_report_without_bounce(struct query *ctl, struct msgblk *msg)
591 /* handle SMTP errors based on the content of SMTP_response */
592 /* atleast one PS_TRANSIENT: do not send the bounce mail, keep the mail;
593 * no PS_TRANSIENT, atleast one PS_SUCCESS: send the bounce mail, delete the mail;
594 * no PS_TRANSIENT, no PS_SUCCESS: do not send the bounce mail, delete the mail */
596 int smtperr = atoi(smtp_response);
598 if (str_find(&ctl->antispam, smtperr))
606 report(stderr, GT_("%cMTP error: %s\n"),
612 case 552: /* message exceeds fixed maximum message size */
617 case 553: /* invalid sending domain */
618 #ifdef __DONT_FEED_THE_SPAMMERS__
621 #endif /* __DONT_FEED_THE_SPAMMERS__ */
625 /* bounce non-transient errors back to the sender */
626 if (smtperr >= 500 && smtperr <= 599)
628 return(PS_TRANSIENT);
632 /* these are shared by open_sink and stuffline */
635 int stuffline(struct query *ctl, char *buf)
636 /* ship a line to the given control block's output sink (SMTP server or MDA) */
641 /* The line may contain NUL characters. Find the last char to use
642 * -- the real line termination is the sequence "\n\0".
644 last = buf + 1; /* last[-1] must be valid! */
645 while ((last += strlen(last)) && (last[-1] != '\n'))
648 /* fix message lines that have only \n termination (for qmail) */
651 if (last - 1 == buf || last[-2] != '\r')
660 phase = FORWARDING_WAIT;
663 * SMTP byte-stuffing. We only do this if the protocol does *not*
664 * use .<CR><LF> as EOM. If it does, the server will already have
665 * decorated any . lines it sends back up.
669 if (ctl->server.base_protocol->delimited) /* server has already byte-stuffed */
674 /* writing to SMTP, leave the byte-stuffing in place */;
677 else /* if (!protocol->delimited) -- not byte-stuffed already */
679 if (!ctl->mda) /* byte-stuff it */
682 SockWrite(ctl->smtp_socket, buf, 1);
685 fwrite(buf, 1, 1, sinkfp);
691 /* we may need to strip carriage returns */
696 for (sp = tp = buf; sp < last; sp++)
704 if (ctl->mda || ctl->bsmtp)
705 n = fwrite(buf, last - buf, 1, sinkfp);
706 else if (ctl->smtp_socket != -1)
707 n = SockWrite(ctl->smtp_socket, buf, last - buf);
714 static int open_bsmtp_sink(struct query *ctl, struct msgblk *msg,
715 int *good_addresses, int *bad_addresses)
716 /* open a BSMTP stream */
720 if (strcmp(ctl->bsmtp, "-") == 0)
723 sinkfp = fopen(ctl->bsmtp, "a");
725 /* see the ap computation under the SMTP branch */
727 "MAIL FROM:%s", (msg->return_path[0]) ? msg->return_path : user);
729 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
730 fputs(" BODY=8BITMIME", sinkfp);
731 else if (ctl->mimemsg & MSG_IS_7BIT)
732 fputs(" BODY=7BIT", sinkfp);
734 /* exim's BSMTP processor does not handle SIZE */
735 /* fprintf(sinkfp, " SIZE=%d", msg->reallen); */
737 fprintf(sinkfp, "\r\n");
740 * RFC 1123 requires that the domain name part of the
741 * RCPT TO address be "canonicalized", that is a FQDN
742 * or MX but not a CNAME. Some listeners (like exim)
743 * enforce this. Now that we have the actual hostname,
744 * compute what we should canonicalize with.
746 ctl->destaddr = ctl->smtpaddress ? ctl->smtpaddress : "localhost";
749 for (idp = msg->recipients; idp; idp = idp->next)
750 if (idp->val.status.mark == XMIT_ACCEPT)
752 fprintf(sinkfp, "RCPT TO: %s\r\n",
753 rcpt_address (ctl, idp->id, 1));
757 fputs("DATA\r\n", sinkfp);
761 report(stderr, GT_("BSMTP file open or preamble write failed\n"));
768 /* this is experimental and will be removed if double bounces are reported */
769 #define EXPLICIT_BOUNCE_ON_BAD_ADDRESS
772 static const char *is_quad(const char *q)
773 /* Check if the string passed in points to what could be one quad of a
774 * dotted-quad IP address. Requirements are that the string is not a
775 * NULL pointer, begins with a period (which is skipped) or a digit
776 * and ends with a period or a NULL. If these requirements are met, a
777 * pointer to the last character (the period or the NULL character) is
778 * returned; otherwise NULL.
787 for(r=q;isdigit((unsigned char)*r);r++)
789 if ( ((*r) && (*r != '.')) || ((r-q) < 1) || ((r-q)>3) )
791 /* Make sure quad is < 255 */
800 else if (*(q+1) == '5')
810 static int is_dottedquad(const char *hostname)
811 /* Returns a true value if the passed in string looks like an IP
812 * address in dotted-quad form, and a false value otherwise.
816 return ((hostname=is_quad(is_quad(is_quad(is_quad(hostname))))) != NULL) &&
820 static int open_smtp_sink(struct query *ctl, struct msgblk *msg,
821 int *good_addresses, int *bad_addresses)
822 /* open an SMTP stream */
826 char options[MSGBUFSIZE];
827 char addr[HOSTLEN+USERNAMELEN+1];
828 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
829 char **from_responses;
830 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
832 int force_transient_error = 0;
836 * Compute ESMTP options.
839 if (ctl->server.esmtp_options & ESMTP_8BITMIME) {
840 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
841 strcpy(options, " BODY=8BITMIME");
842 else if (ctl->mimemsg & MSG_IS_7BIT)
843 strcpy(options, " BODY=7BIT");
846 if ((ctl->server.esmtp_options & ESMTP_SIZE) && msg->reallen > 0)
847 sprintf(options + strlen(options), " SIZE=%d", msg->reallen);
850 * Try to get the SMTP listener to take the Return-Path
851 * address as MAIL FROM. If it won't, fall back on the
852 * remotename and mailserver host. This won't affect replies,
853 * which use the header From address anyway; the MAIL FROM
854 * address is a place for the SMTP listener to send
855 * bouncemail. The point is to guarantee a FQDN in the MAIL
856 * FROM line -- some SMTP listeners, like smail, become
859 * RFC 1123 requires that the domain name part of the
860 * MAIL FROM address be "canonicalized", that is a
861 * FQDN or MX but not a CNAME. We'll assume the Return-Path
862 * header is already in this form here (it certainly
863 * is if rewrite is on). RFC 1123 is silent on whether
864 * a nonexistent hostname part is considered canonical.
866 * This is a potential problem if the MTAs further upstream
867 * didn't pass canonicalized From/Return-Path lines, *and* the
868 * local SMTP listener insists on them.
870 * Handle the case where an upstream MTA is setting a return
871 * path equal to "@". Ghod knows why anyone does this, but
872 * it's been reported to happen in mail from Amazon.com and
875 * Also, if the hostname is a dotted quad, wrap it in square brackets.
876 * Apparently this is required by RFC2821, section 4.1.3.
878 if (!msg->return_path[0] || (msg->return_path[0] == '@'))
880 if (strchr(ctl->remotename,'@') || strchr(ctl->remotename,'!'))
882 snprintf(addr, sizeof(addr), "%s", ctl->remotename);
884 else if (is_dottedquad(ctl->server.truename))
886 snprintf(addr, sizeof(addr), "%s@[%s]", ctl->remotename,
887 ctl->server.truename);
891 snprintf(addr, sizeof(addr),
892 "%s@%s", ctl->remotename, ctl->server.truename);
896 else if (strchr(msg->return_path,'@') || strchr(msg->return_path,'!'))
897 ap = msg->return_path;
898 /* in case Return-Path was "<>" we want to preserve that */
899 else if (strcmp(msg->return_path,"<>") == 0)
900 ap = msg->return_path;
901 else /* in case Return-Path existed but was local */
903 if (is_dottedquad(ctl->server.truename))
905 snprintf(addr, sizeof(addr), "%s@[%s]", msg->return_path,
906 ctl->server.truename);
910 snprintf(addr, sizeof(addr), "%s@%s",
911 msg->return_path, ctl->server.truename);
916 if ((smtp_err = SMTP_from(ctl->smtp_socket, ap, options)) == SM_UNRECOVERABLE)
919 return(PS_TRANSIENT);
921 if (smtp_err != SM_OK)
923 int err = handle_smtp_report(ctl, msg);
925 SMTP_rset(ctl->smtp_socket); /* 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 xalloca(from_responses, char **, 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, address)) == SM_UNRECOVERABLE)
946 return(PS_TRANSIENT);
948 if (smtp_err == SM_OK)
952 switch (handle_smtp_report_without_bounce(ctl, msg))
955 force_transient_error = 1;
959 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
960 xalloca(from_responses[*bad_addresses],
962 strlen(smtp_response)+1);
963 strcpy(from_responses[*bad_addresses], smtp_response);
964 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
967 idp->val.status.mark = XMIT_RCPTBAD;
968 if (outlevel >= O_VERBOSE)
970 GT_("%cMTP listener doesn't like recipient address `%s'\n"),
971 ctl->listener, address);
975 if (outlevel >= O_VERBOSE)
977 GT_("%cMTP listener doesn't really like recipient address `%s'\n"),
978 ctl->listener, address);
984 if (force_transient_error) {
985 /* do not risk dataloss due to overengineered multidrop
986 * crap. If one of the recipients returned PS_TRANSIENT,
987 * we return exactly that.
989 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
990 return(PS_TRANSIENT);
992 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
994 * This should not be necessary, because the SMTP listener itself
995 * should genrate a bounce for the bad address.
998 send_bouncemail(ctl, msg, XMIT_RCPTBAD,
999 "Some addresses were rejected by the MDA fetchmail forwards to.\r\n",
1000 *bad_addresses, from_responses);
1001 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
1004 * It's tempting to do local notification only if bouncemail was
1005 * insufficient -- that is, to add && total_addresses > *bad_addresses
1006 * to the test here. The problem with this theory is that it would
1007 * make initial diagnosis of a broken multidrop configuration very
1008 * hard -- most single-recipient messages would just invisibly bounce.
1010 if (!(*good_addresses))
1012 if (!run.postmaster[0])
1014 if (outlevel >= O_VERBOSE)
1015 report(stderr, GT_("no address matches; no postmaster set.\n"));
1016 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
1019 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket,
1020 rcpt_address (ctl, run.postmaster, 0))) == SM_UNRECOVERABLE)
1023 return(PS_TRANSIENT);
1025 if (smtp_err != SM_OK)
1027 report(stderr, GT_("can't even send to %s!\n"), run.postmaster);
1028 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
1032 if (outlevel >= O_VERBOSE)
1033 report(stderr, GT_("no address matches; forwarding to %s.\n"), run.postmaster);
1037 * Tell the listener we're ready to send data.
1038 * Some listeners (like zmailer) may return antispam errors here.
1040 if ((smtp_err = SMTP_data(ctl->smtp_socket)) == SM_UNRECOVERABLE)
1043 return(PS_TRANSIENT);
1045 if (smtp_err != SM_OK)
1047 int err = handle_smtp_report(ctl, msg);
1048 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1053 * We need to stash this away in order to know how many
1054 * response lines to expect after the LMTP end-of-message.
1056 lmtp_responses = *good_addresses;
1061 static int open_mda_sink(struct query *ctl, struct msgblk *msg,
1062 int *good_addresses, int *bad_addresses)
1063 /* open a stream to a local MDA */
1067 #endif /* HAVE_SETEUID */
1069 int length = 0, fromlen = 0, nameslen = 0;
1070 char *names = NULL, *before, *after, *from = NULL;
1072 ctl->destaddr = "localhost";
1074 for (idp = msg->recipients; idp; idp = idp->next)
1075 if (idp->val.status.mark == XMIT_ACCEPT)
1076 (*good_addresses)++;
1078 length = strlen(ctl->mda);
1079 before = xstrdup(ctl->mda);
1081 /* get user addresses for %T (or %s for backward compatibility) */
1082 if (strstr(before, "%s") || strstr(before, "%T"))
1085 * We go through this in order to be able to handle very
1086 * long lists of users and (re)implement %s.
1089 for (idp = msg->recipients; idp; idp = idp->next)
1090 if ((idp->val.status.mark == XMIT_ACCEPT))
1091 nameslen += (strlen(idp->id) + 1); /* string + ' ' */
1092 if ((*good_addresses == 0))
1093 nameslen = strlen(run.postmaster);
1095 names = (char *)xmalloc(nameslen + 1); /* account for '\0' */
1096 if (*good_addresses == 0)
1097 strcpy(names, run.postmaster);
1101 for (idp = msg->recipients; idp; idp = idp->next)
1102 if (idp->val.status.mark == XMIT_ACCEPT)
1104 strcat(names, idp->id);
1107 names[--nameslen] = '\0'; /* chop trailing space */
1113 /* get From address for %F */
1114 if (strstr(before, "%F"))
1116 from = xstrdup(msg->return_path);
1120 fromlen = strlen(from);
1123 /* do we have to build an mda string? */
1128 /* find length of resulting mda string */
1130 while ((sp = strstr(sp, "%s"))) {
1131 length += nameslen; /* subtract %s and add '' */
1135 while ((sp = strstr(sp, "%T"))) {
1136 length += nameslen; /* subtract %T and add '' */
1140 while ((sp = strstr(sp, "%F"))) {
1141 length += fromlen; /* subtract %F and add '' */
1145 after = xmalloc(length + 1);
1147 /* copy mda source string to after, while expanding %[sTF] */
1148 for (dp = after, sp = before; (*dp = *sp); dp++, sp++) {
1149 if (sp[0] != '%') continue;
1151 /* need to expand? BTW, no here overflow, because in
1152 ** the worst case (end of string) sp[1] == '\0' */
1153 if (sp[1] == 's' || sp[1] == 'T') {
1158 sp++; /* position sp over [sT] */
1159 dp--; /* adjust dp */
1160 } else if (sp[1] == 'F') {
1165 sp++; /* position sp over F */
1166 dp--; /* adjust dp */
1185 if (outlevel >= O_DEBUG)
1186 report(stdout, GT_("about to deliver with: %s\n"), before);
1190 * Arrange to run with user's permissions if we're root.
1191 * This will initialize the ownership of any files the
1192 * MDA creates properly. (The seteuid call is available
1193 * under all BSDs and Linux)
1195 orig_uid = getuid();
1197 #endif /* HAVE_SETEUID */
1199 sinkfp = popen(before, "w");
1204 /* this will fail quietly if we didn't start as root */
1206 #endif /* HAVE_SETEUID */
1210 report(stderr, GT_("MDA open failed\n"));
1215 * We need to disable the normal SIGCHLD handling here because
1216 * sigchld_handler() would reap away the error status, returning
1217 * error status instead of 0 for successful completion.
1219 set_signal_handler(SIGCHLD, SIG_DFL);
1224 int open_sink(struct query *ctl, struct msgblk *msg,
1225 int *good_addresses, int *bad_addresses)
1226 /* set up sinkfp to be an input sink we can ship a message to */
1228 *bad_addresses = *good_addresses = 0;
1230 if (ctl->bsmtp) /* dump to a BSMTP batch file */
1231 return(open_bsmtp_sink(ctl, msg, good_addresses, bad_addresses));
1233 * Try to forward to an SMTP or LMTP listener. If the attempt to
1234 * open a socket fails, fall through to attempt delivery via
1237 else if (!ctl->mda && smtp_open(ctl) != -1)
1238 return(open_smtp_sink(ctl, msg, good_addresses, bad_addresses));
1241 * Awkward case. User didn't specify an MDA. Our attempt to get a
1242 * listener socket failed. Try to cope anyway -- initial configuration
1243 * may have found procmail.
1247 report(stderr, GT_("%cMTP connect to %s failed\n"),
1249 ctl->smtphost ? ctl->smtphost : "localhost");
1251 #ifndef FALLBACK_MDA
1252 /* No fallback MDA declared. Bail out. */
1256 * If user had things set up to forward offsite, no way
1257 * we want to deliver locally!
1259 if (ctl->smtphost && strcmp(ctl->smtphost, "localhost"))
1263 * User was delivering locally. We have a fallback MDA.
1264 * Latch it in place, logging the error, and fall through.
1265 * Set stripcr as we would if MDA had been the initial transport
1267 ctl->mda = FALLBACK_MDA;
1269 ctl->stripcr = TRUE;
1271 report(stderr, GT_("can't raise the listener; falling back to %s"),
1276 if (ctl->mda) /* must deliver through an MDA */
1277 return(open_mda_sink(ctl, msg, good_addresses, bad_addresses));
1282 void release_sink(struct query *ctl)
1283 /* release the per-message output sink, whether it's a pipe or SMTP socket */
1285 if (ctl->bsmtp && sinkfp)
1287 if (strcmp(ctl->bsmtp, "-"))
1290 sinkfp = (FILE *)NULL;
1298 sinkfp = (FILE *)NULL;
1300 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1304 int close_sink(struct query *ctl, struct msgblk *msg, flag forward)
1305 /* perform end-of-message actions on the current output sink */
1312 /* close the delivery pipe, we'll reopen before next message */
1315 rc = pclose(sinkfp);
1316 sinkfp = (FILE *)NULL;
1321 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1325 if (WIFSIGNALED(rc)) {
1327 GT_("MDA died of signal %d\n"), WTERMSIG(rc));
1328 } else if (WIFEXITED(rc)) {
1330 GT_("MDA returned nonzero status %d\n"), WEXITSTATUS(rc));
1333 GT_("Strange: MDA pclose returned %d, cannot handle at %s:%d\n"), rc, __FILE__, __LINE__);
1339 else if (ctl->bsmtp && sinkfp)
1343 /* implicit disk-full check here... */
1344 fputs(".\r\n", sinkfp);
1345 error = ferror(sinkfp);
1346 if (strcmp(ctl->bsmtp, "-"))
1348 if (fclose(sinkfp) == EOF) error = 1;
1349 sinkfp = (FILE *)NULL;
1354 GT_("Message termination or close of BSMTP file failed\n"));
1360 /* write message terminator */
1361 if ((smtp_err = SMTP_eom(ctl->smtp_socket)) == SM_UNRECOVERABLE)
1366 if (smtp_err != SM_OK)
1368 if (handle_smtp_report(ctl, msg) != PS_REFUSED)
1370 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1375 report(stderr, GT_("SMTP listener refused delivery\n"));
1376 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1382 * If this is an SMTP connection, SMTP_eom() ate the response.
1383 * But could be this is an LMTP connection, in which case we have to
1384 * interpret either (a) a single 503 response meaning there
1385 * were no successful RCPT TOs, or (b) a variable number of
1386 * responses, one for each successful RCPT TO. We need to send
1387 * bouncemail on each failed response and then return TRUE anyway,
1388 * otherwise the message will get left in the queue and resent
1389 * to people who got it the first time.
1391 if (ctl->listener == LMTP_MODE)
1393 if (lmtp_responses == 0)
1395 SMTP_ok(ctl->smtp_socket);
1398 * According to RFC2033, 503 is the only legal response
1399 * if no RCPT TO commands succeeded. No error recovery
1400 * is really possible here, as we have no idea what
1401 * insane thing the listener might be doing if it doesn't
1404 if (atoi(smtp_response) == 503)
1405 report(stderr, GT_("LMTP delivery error on EOM\n"));
1408 GT_("Unexpected non-503 response to LMTP EOM: %s\n"),
1412 * It's not completely clear what to do here. We choose to
1413 * interpret delivery failure here as a transient error,
1414 * the same way SMTP delivery failure is handled. If we're
1415 * wrong, an undead message will get stuck in the queue.
1424 /* eat the RFC2033-required responses, saving errors */
1425 xalloca(responses, char **, sizeof(char *) * lmtp_responses);
1426 for (errors = i = 0; i < lmtp_responses; i++)
1428 if ((smtp_err = SMTP_ok(ctl->smtp_socket)) == SM_UNRECOVERABLE)
1433 if (smtp_err == SM_OK)
1434 responses[i] = (char *)NULL;
1437 xalloca(responses[errors],
1439 strlen(smtp_response)+1);
1440 strcpy(responses[errors], smtp_response);
1446 return(TRUE); /* all deliveries succeeded */
1449 * One or more deliveries failed.
1450 * If we can bounce a failures list back to the
1451 * sender, and the postmaster does not want to
1452 * deal with the bounces return TRUE, deleting the
1453 * message from the server so it won't be
1454 * re-forwarded on subsequent poll cycles.
1456 return(send_bouncemail(ctl, msg, XMIT_ACCEPT,
1457 "LMTP partial delivery failure.\r\n",
1458 errors, responses));
1466 int open_warning_by_mail(struct query *ctl, struct msgblk *msg)
1467 /* set up output sink for a mailed warning to calling user */
1472 * Dispatching warning email is a little complicated. The problem is
1473 * that we have to deal with three distinct cases:
1475 * 1. Single-drop running from user account. Warning mail should
1476 * go to the local name for which we're collecting (coincides
1477 * with calling user).
1479 * 2. Single-drop running from root or other privileged ID, with rc
1480 * file generated on the fly (Ken Estes's weird setup...) Mail
1481 * should go to the local name for which we're collecting (does not
1482 * coincide with calling user).
1484 * 3. Multidrop. Mail must go to postmaster. We leave the recipients
1485 * member null so this message will fall through to run.postmaster.
1487 * The zero in the reallen element means we won't pass a SIZE
1488 * option to ESMTP; the message length would be more trouble than
1489 * it's worth to compute.
1491 struct msgblk reply = {NULL, NULL, "FETCHMAIL-DAEMON@", 0, 0};
1494 strcat(reply.return_path, ctl->smtpaddress ? ctl->smtpaddress :
1497 if (!MULTIDROP(ctl)) /* send to calling user */
1499 save_str(&reply.recipients, ctl->localnames->id, XMIT_ACCEPT);
1500 status = open_sink(ctl, &reply, &good, &bad);
1501 free_str_list(&reply.recipients);
1503 else /* send to postmaster */
1504 status = open_sink(ctl, &reply, &good, &bad);
1506 stuff_warning(NULL, ctl, "Date: %s", rfc822timestamp());
1507 stuff_warning(NULL, ctl, "MIME-Version: 1.0");
1508 stuff_warning(NULL, ctl, "Content-Transfer-Encoding: 8bit");
1509 stuff_warning(NULL, ctl, "Content-Type: text/plain; charset=\"%s\"", iana_charset);
1514 /* format and ship a warning message line by mail */
1515 /* if rfc2047charset is non-NULL, encode the line (that is assumed to be
1516 * a header line) as per RFC-2047 using rfc2047charset as the character
1518 #if defined(HAVE_STDARG_H)
1519 void stuff_warning(const char *rfc2047charset, struct query *ctl, const char *fmt, ... )
1521 void stuff_warning(rfc2047charset, ctl, fmt, va_alist)
1522 const char *charset;
1524 const char *fmt; /* printf-style format */
1528 /* make huge -- i18n can bulk up error messages a lot */
1529 char buf[2*MSGBUFSIZE+4];
1533 * stuffline() requires its input to be writeable (for CR stripping),
1534 * so we needed to copy the message to a writeable buffer anyway in
1535 * case it was a string constant. We make a virtue of that necessity
1536 * here by supporting stdargs/varargs.
1538 #if defined(HAVE_STDARG_H)
1543 vsnprintf(buf, sizeof(buf), fmt, ap);
1546 snprintf(buf+strlen(buf), sizeof(buf)-strlen(buf), "\r\n");
1548 /* guard against very long lines */
1549 buf[MSGBUFSIZE+1] = '\r';
1550 buf[MSGBUFSIZE+2] = '\n';
1551 buf[MSGBUFSIZE+3] = '\0';
1553 stuffline(ctl, rfc2047charset != NULL ? rfc2047e(buf, rfc2047charset) : buf);
1556 void close_warning_by_mail(struct query *ctl, struct msgblk *msg)
1557 /* sign and send mailed warnings */
1559 stuff_warning(NULL, ctl, GT_("-- \nThe Fetchmail Daemon"));
1560 close_sink(ctl, msg, TRUE);
1563 /* sink.c ends here */