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];
268 snprintf(addr, sizeof (addr), "%s", id);
270 sprintf(addr, "%s", id);
271 #endif /* HAVE_SNPRINTF */
273 else if (usesmtpname && ctl->smtpname)
276 snprintf(addr, sizeof (addr), "%s", ctl->smtpname);
278 sprintf(addr, "%s", ctl->smtpname);
279 #endif /* HAVE_SNPRINTF */
284 snprintf(addr, sizeof (addr), "%s@%s", id, ctl->destaddr);
286 sprintf(addr, "%s@%s", id, ctl->destaddr);
287 #endif /* HAVE_SNPRINTF */
292 static int send_bouncemail(struct query *ctl, struct msgblk *msg,
293 int userclass, char *message,
294 int nerrors, char *errors[])
295 /* bounce back an error report a la RFC 1892 */
297 char daemon_name[15 + HOSTLEN] = "MAILER-DAEMON@";
298 char boundary[BUFSIZ], *bounce_to;
300 static char *fqdn_of_host = NULL;
301 const char *md1 = "MAILER-DAEMON", *md2 = "MAILER-DAEMON@";
303 /* don't bounce in reply to undeliverable bounces */
304 if (!msg->return_path[0] ||
305 strcmp(msg->return_path, "<>") == 0 ||
306 strcasecmp(msg->return_path, md1) == 0 ||
307 strncasecmp(msg->return_path, md2, strlen(md2)) == 0)
310 bounce_to = (run.bouncemail ? msg->return_path : run.postmaster);
312 SMTP_setmode(SMTP_MODE);
314 /* can't just use fetchmailhost here, it might be localhost */
315 if (fqdn_of_host == NULL)
316 fqdn_of_host = host_fqdn();
317 strcat(daemon_name, fqdn_of_host);
319 /* we need only SMTP for this purpose */
320 if ((sock = SockOpen("localhost", SMTP_PORT, NULL, NULL)) == -1)
323 if (SMTP_ok(sock) != SM_OK)
329 if (SMTP_helo(sock, fetchmailhost) != SM_OK
330 || SMTP_from(sock, "<>", (char *)NULL) != SM_OK
331 || SMTP_rcpt(sock, bounce_to) != SM_OK
332 || SMTP_data(sock) != SM_OK)
339 /* our first duty is to keep the sacred foo counters turning... */
341 snprintf(boundary, sizeof(boundary),
344 #endif /* HAVE_SNPRINTF */
345 "foo-mani-padme-hum-%d-%d-%ld",
346 (int)getpid(), (int)getppid(), time((time_t *)NULL));
348 if (outlevel >= O_VERBOSE)
349 report(stdout, GT_("SMTP: (bounce-message body)\n"));
351 /* this will usually go to sylog... */
352 report(stderr, GT_("mail from %s bounced to %s\n"),
353 daemon_name, bounce_to);
356 /* bouncemail headers */
357 SockPrintf(sock, "Subject: Mail delivery failed: returning message to sender\r\n");
358 SockPrintf(sock, "From: Mail Delivery System <%s>\r\n", daemon_name);
359 SockPrintf(sock, "To: %s\r\n", bounce_to);
360 SockPrintf(sock, "MIME-Version: 1.0\r\n");
361 SockPrintf(sock, "Content-Type: multipart/report; report-type=delivery-status;\r\n\tboundary=\"%s\"\r\n", boundary);
362 SockPrintf(sock, "\r\n");
364 /* RFC1892 part 1 -- human-readable message */
365 SockPrintf(sock, "--%s\r\n", boundary);
366 SockPrintf(sock,"Content-Type: text/plain\r\n");
367 SockPrintf(sock, "\r\n");
368 SockPrintf(sock, "This message was created automatically by mail delivery software.\r\n\r\n");
369 SockPrintf(sock, "A message that you sent could not be delivered to one or more of its\r\n");
370 SockPrintf(sock, "recipients. This is a permanent error. The following address(es) failed:\r\n");
371 SockPrintf(sock, "\r\n");
379 for (idp = msg->recipients; idp; idp = idp->next)
381 if (idp->val.status.mark == userclass)
384 SockPrintf(sock, "%s\r\n", rcpt_address (ctl, idp->id, 1));
386 if (nerrors == 1) error = errors[0];
387 else if (nerrors <= nusers)
389 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
392 else error = errors[nusers++];
394 SockPrintf(sock, " SMTP error: %s\r\n\r\n", error);
398 /* RFC1892 part 2 -- machine-readable responses */
399 SockPrintf(sock, "--%s\r\n", boundary);
400 SockPrintf(sock,"Content-Type: message/delivery-status\r\n");
401 SockPrintf(sock, "\r\n");
402 SockPrintf(sock, "Reporting-MTA: dns; %s\r\n", fqdn_of_host);
405 for (idp = msg->recipients; idp; idp = idp->next)
406 if (idp->val.status.mark == userclass)
409 /* Minimum RFC1894 compliance + Diagnostic-Code field */
410 SockPrintf(sock, "\r\n");
411 SockPrintf(sock, "Final-Recipient: rfc822; %s\r\n",
412 rcpt_address (ctl, idp->id, 1));
413 SockPrintf(sock, "Last-Attempt-Date: %s\r\n", rfc822timestamp());
414 SockPrintf(sock, "Action: failed\r\n");
417 /* one error applies to all users */
419 else if (nerrors <= nusers)
421 SockPrintf(sock, "Internal error: SMTP error count doesn't match number of recipients.\r\n");
425 /* errors correspond 1-1 to selected users */
426 error = errors[nusers++];
428 if (strlen(error) > 9 && isdigit((unsigned char)error[4])
429 && error[5] == '.' && isdigit((unsigned char)error[6])
430 && error[7] == '.' && isdigit((unsigned char)error[8]))
431 /* Enhanced status code available, use it */
432 SockPrintf(sock, "Status: %5.5s\r\n", &(error[4]));
434 /* Enhanced status code not available, fake one */
435 SockPrintf(sock, "Status: %c.0.0\r\n", error[0]);
436 SockPrintf(sock, "Diagnostic-Code: %s\r\n", error);
438 SockPrintf(sock, "\r\n");
441 /* RFC1892 part 3 -- headers of undelivered message */
442 SockPrintf(sock, "--%s\r\n", boundary);
443 SockPrintf(sock, "Content-Type: text/rfc822-headers\r\n");
444 SockPrintf(sock, "\r\n");
447 SockWrite(sock, msg->headers, strlen(msg->headers));
448 SockPrintf(sock, "\r\n");
450 SockPrintf(sock, "--%s--\r\n", boundary);
452 if (SMTP_eom(sock) != SM_OK || SMTP_quit(sock))
463 static int handle_smtp_report(struct query *ctl, struct msgblk *msg)
464 /* handle SMTP errors based on the content of SMTP_response */
465 /* return of PS_REFUSED deletes mail from the server; PS_TRANSIENT keeps it */
467 int smtperr = atoi(smtp_response);
472 xalloca(responses[0], char *, strlen(smtp_response)+1);
473 strcpy(responses[0], smtp_response);
477 * Don't do this! It can really mess you up if, for example, you're
478 * reporting an error with a single RCPT TO address among several;
479 * RSET discards the message body and it doesn't get sent to the
482 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
483 if (outlevel >= O_DEBUG)
484 report(stdout, GT_("Saved error is still %d\n"), smtperr);
485 #endif /* __UNUSED */
488 * Note: send_bouncemail message strings are not made subject
489 * to gettext translation because (a) they're going to be
490 * embedded in a text/plain 7bit part, and (b) they're
491 * going to be associated with listener error-response
492 * messages, which are probably in English (none of the
493 * MTAs I know about are internationalized).
495 for( walk = ctl->antispam; walk; walk = walk->next )
496 if ( walk->val.status.num == smtperr )
502 /* if (str_find(&ctl->antispam, smtperr)) */
506 * SMTP listener explicitly refuses to deliver mail
507 * coming from this address, probably due to an
508 * anti-spam domain exclusion. Respect this. Don't
509 * try to ship the message, and don't prevent it from
510 * being deleted. There's no point in bouncing the
511 * email either since most spammers don't put their
512 * real return email address anywhere in the headers
513 * (unless the user insists with the SET SPAMBOUNCE
518 * 571 = sendmail's "unsolicited email refused"
519 * 550 = exim's new antispam response (temporary)
520 * 501 = exim's old antispam response
521 * 554 = Postfix antispam response.
528 snprintf(rejmsg, sizeof(rejmsg),
531 #endif /* HAVE_SNPRINTF */
532 "spam filter or virus scanner rejected message because:\r\n"
533 "%s\r\n", responses[0]);
535 send_bouncemail(ctl, msg, XMIT_ACCEPT,
536 rejmsg, 1, responses);
542 * Suppress error message only if the response specifically
543 * meant `excluded for policy reasons'. We *should* see
544 * an error when the return code is less specific.
547 report(stderr, GT_("%cMTP error: %s\n"),
553 case 552: /* message exceeds fixed maximum message size */
555 * Permanent no-go condition on the
556 * ESMTP server. Don't try to ship the message,
557 * and allow it to be deleted.
560 send_bouncemail(ctl, msg, XMIT_ACCEPT,
561 "This message was too large (SMTP error 552).\r\n",
565 case 553: /* invalid sending domain */
567 * These latter days 553 usually means a spammer is trying to
568 * cover his tracks. We never bouncemail on these, because
569 * (a) the return address is invalid by definition, and
570 * (b) we wouldn't want spammers to get confirmation that
571 * this address is live, anyway.
573 #ifdef __DONT_FEED_THE_SPAMMERS__
575 send_bouncemail(ctl, msg, XMIT_ACCEPT,
576 "Invalid address in MAIL FROM (SMTP error 553).\r\n",
578 #endif /* __DONT_FEED_THE_SPAMMERS__ */
582 /* bounce non-transient errors back to the sender */
583 if (smtperr >= 500 && smtperr <= 599)
585 send_bouncemail(ctl, msg, XMIT_ACCEPT,
586 "General SMTP/ESMTP error.\r\n",
591 * We're going to end up here on 4xx errors, like:
593 * 451: temporarily unable to identify sender (exim)
594 * 452: temporary out-of-queue-space condition on the ESMTP server.
596 * These are temporary errors. Don't try to ship the message,
597 * and suppress deletion so it can be retried on a future
600 * Bouncemail *might* be appropriate here as a delay
601 * notification (note; if we ever add this, we must make
602 * sure the RFC1894 Action field is "delayed" rather than
603 * "failed"). But it's not really necessary because
604 * these are not actual failures, we're very likely to be
605 * able to recover on the next cycle.
607 return(PS_TRANSIENT);
611 static int handle_smtp_report_without_bounce(struct query *ctl, struct msgblk *msg)
612 /* handle SMTP errors based on the content of SMTP_response */
613 /* atleast one PS_TRANSIENT: do not send the bounce mail, keep the mail;
614 * no PS_TRANSIENT, atleast one PS_SUCCESS: send the bounce mail, delete the mail;
615 * no PS_TRANSIENT, no PS_SUCCESS: do not send the bounce mail, delete the mail */
617 int smtperr = atoi(smtp_response);
619 if (str_find(&ctl->antispam, smtperr))
627 report(stderr, GT_("%cMTP error: %s\n"),
633 case 552: /* message exceeds fixed maximum message size */
638 case 553: /* invalid sending domain */
639 #ifdef __DONT_FEED_THE_SPAMMERS__
642 #endif /* __DONT_FEED_THE_SPAMMERS__ */
646 /* bounce non-transient errors back to the sender */
647 if (smtperr >= 500 && smtperr <= 599)
649 return(PS_TRANSIENT);
653 /* these are shared by open_sink and stuffline */
656 int stuffline(struct query *ctl, char *buf)
657 /* ship a line to the given control block's output sink (SMTP server or MDA) */
662 /* The line may contain NUL characters. Find the last char to use
663 * -- the real line termination is the sequence "\n\0".
665 last = buf + 1; /* last[-1] must be valid! */
666 while ((last += strlen(last)) && (last[-1] != '\n'))
669 /* fix message lines that have only \n termination (for qmail) */
672 if (last - 1 == buf || last[-2] != '\r')
681 phase = FORWARDING_WAIT;
684 * SMTP byte-stuffing. We only do this if the protocol does *not*
685 * use .<CR><LF> as EOM. If it does, the server will already have
686 * decorated any . lines it sends back up.
690 if (ctl->server.base_protocol->delimited) /* server has already byte-stuffed */
695 /* writing to SMTP, leave the byte-stuffing in place */;
698 else /* if (!protocol->delimited) -- not byte-stuffed already */
700 if (!ctl->mda) /* byte-stuff it */
703 SockWrite(ctl->smtp_socket, buf, 1);
706 fwrite(buf, 1, 1, sinkfp);
712 /* we may need to strip carriage returns */
717 for (sp = tp = buf; sp < last; sp++)
725 if (ctl->mda || ctl->bsmtp)
726 n = fwrite(buf, last - buf, 1, sinkfp);
727 else if (ctl->smtp_socket != -1)
728 n = SockWrite(ctl->smtp_socket, buf, last - buf);
735 static int open_bsmtp_sink(struct query *ctl, struct msgblk *msg,
736 int *good_addresses, int *bad_addresses)
737 /* open a BSMTP stream */
741 if (strcmp(ctl->bsmtp, "-") == 0)
744 sinkfp = fopen(ctl->bsmtp, "a");
746 /* see the ap computation under the SMTP branch */
748 "MAIL FROM:%s", (msg->return_path[0]) ? msg->return_path : user);
750 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
751 fputs(" BODY=8BITMIME", sinkfp);
752 else if (ctl->mimemsg & MSG_IS_7BIT)
753 fputs(" BODY=7BIT", sinkfp);
755 /* exim's BSMTP processor does not handle SIZE */
756 /* fprintf(sinkfp, " SIZE=%d", msg->reallen); */
758 fprintf(sinkfp, "\r\n");
761 * RFC 1123 requires that the domain name part of the
762 * RCPT TO address be "canonicalized", that is a FQDN
763 * or MX but not a CNAME. Some listeners (like exim)
764 * enforce this. Now that we have the actual hostname,
765 * compute what we should canonicalize with.
767 ctl->destaddr = ctl->smtpaddress ? ctl->smtpaddress : "localhost";
770 for (idp = msg->recipients; idp; idp = idp->next)
771 if (idp->val.status.mark == XMIT_ACCEPT)
773 fprintf(sinkfp, "RCPT TO: %s\r\n",
774 rcpt_address (ctl, idp->id, 1));
778 fputs("DATA\r\n", sinkfp);
782 report(stderr, GT_("BSMTP file open or preamble write failed\n"));
789 /* this is experimental and will be removed if double bounces are reported */
790 #define EXPLICIT_BOUNCE_ON_BAD_ADDRESS
793 static const char *is_quad(const char *q)
794 /* Check if the string passed in points to what could be one quad of a
795 * dotted-quad IP address. Requirements are that the string is not a
796 * NULL pointer, begins with a period (which is skipped) or a digit
797 * and ends with a period or a NULL. If these requirements are met, a
798 * pointer to the last character (the period or the NULL character) is
799 * returned; otherwise NULL.
808 for(r=q;isdigit((unsigned char)*r);r++)
810 if ( ((*r) && (*r != '.')) || ((r-q) < 1) || ((r-q)>3) )
812 /* Make sure quad is < 255 */
821 else if (*(q+1) == '5')
831 static int is_dottedquad(const char *hostname)
832 /* Returns a true value if the passed in string looks like an IP
833 * address in dotted-quad form, and a false value otherwise.
837 return ((hostname=is_quad(is_quad(is_quad(is_quad(hostname))))) != NULL) &&
841 static int open_smtp_sink(struct query *ctl, struct msgblk *msg,
842 int *good_addresses, int *bad_addresses)
843 /* open an SMTP stream */
847 char options[MSGBUFSIZE];
848 char addr[HOSTLEN+USERNAMELEN+1];
849 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
850 char **from_responses;
851 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
853 int force_transient_error = 0;
857 * Compute ESMTP options.
860 if (ctl->server.esmtp_options & ESMTP_8BITMIME) {
861 if (ctl->pass8bits || (ctl->mimemsg & MSG_IS_8BIT))
862 strcpy(options, " BODY=8BITMIME");
863 else if (ctl->mimemsg & MSG_IS_7BIT)
864 strcpy(options, " BODY=7BIT");
867 if ((ctl->server.esmtp_options & ESMTP_SIZE) && msg->reallen > 0)
868 sprintf(options + strlen(options), " SIZE=%d", msg->reallen);
871 * Try to get the SMTP listener to take the Return-Path
872 * address as MAIL FROM. If it won't, fall back on the
873 * remotename and mailserver host. This won't affect replies,
874 * which use the header From address anyway; the MAIL FROM
875 * address is a place for the SMTP listener to send
876 * bouncemail. The point is to guarantee a FQDN in the MAIL
877 * FROM line -- some SMTP listeners, like smail, become
880 * RFC 1123 requires that the domain name part of the
881 * MAIL FROM address be "canonicalized", that is a
882 * FQDN or MX but not a CNAME. We'll assume the Return-Path
883 * header is already in this form here (it certainly
884 * is if rewrite is on). RFC 1123 is silent on whether
885 * a nonexistent hostname part is considered canonical.
887 * This is a potential problem if the MTAs further upstream
888 * didn't pass canonicalized From/Return-Path lines, *and* the
889 * local SMTP listener insists on them.
891 * Handle the case where an upstream MTA is setting a return
892 * path equal to "@". Ghod knows why anyone does this, but
893 * it's been reported to happen in mail from Amazon.com and
896 * Also, if the hostname is a dotted quad, wrap it in square brackets.
897 * Apparently this is required by RFC2821, section 4.1.3.
899 if (!msg->return_path[0] || (msg->return_path[0] == '@'))
901 if (is_dottedquad(ctl->server.truename))
904 snprintf(addr, sizeof(addr),
907 #endif /* HAVE_SNPRINTF */
908 "%s@[%s]", ctl->remotename, ctl->server.truename);
913 snprintf(addr, sizeof(addr),
916 #endif /* HAVE_SNPRINTF */
917 "%s@%s", ctl->remotename, ctl->server.truename);
921 else if (strchr(msg->return_path,'@') || strchr(msg->return_path,'!'))
922 ap = msg->return_path;
923 /* in case Return-Path was "<>" we want to preserve that */
924 else if (strcmp(msg->return_path,"<>") == 0)
925 ap = msg->return_path;
926 else /* in case Return-Path existed but was local */
928 if (is_dottedquad(ctl->server.truename))
931 snprintf(addr, sizeof(addr),
934 #endif /* HAVE_SNPRINTF */
935 "%s@[%s]", msg->return_path, ctl->server.truename);
940 snprintf(addr, sizeof(addr),
943 #endif /* HAVE_SNPRINTF */
944 "%s@%s", msg->return_path, ctl->server.truename);
949 if ((smtp_err = SMTP_from(ctl->smtp_socket, ap, options)) == SM_UNRECOVERABLE)
952 return(PS_TRANSIENT);
954 if (smtp_err != SM_OK)
956 int err = handle_smtp_report(ctl, msg);
958 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
963 * Now list the recipient addressees
966 for (idp = msg->recipients; idp; idp = idp->next)
968 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
969 xalloca(from_responses, char **, sizeof(char *) * total_addresses);
970 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
971 for (idp = msg->recipients; idp; idp = idp->next)
972 if (idp->val.status.mark == XMIT_ACCEPT)
975 address = rcpt_address (ctl, idp->id, 1);
976 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket, address)) == SM_UNRECOVERABLE)
979 return(PS_TRANSIENT);
981 if (smtp_err == SM_OK)
985 switch (handle_smtp_report_without_bounce(ctl, msg))
988 force_transient_error = 1;
992 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
993 xalloca(from_responses[*bad_addresses],
995 strlen(smtp_response)+1);
996 strcpy(from_responses[*bad_addresses], smtp_response);
997 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
1000 idp->val.status.mark = XMIT_RCPTBAD;
1001 if (outlevel >= O_VERBOSE)
1003 GT_("%cMTP listener doesn't like recipient address `%s'\n"),
1004 ctl->listener, address);
1008 if (outlevel >= O_VERBOSE)
1010 GT_("%cMTP listener doesn't really like recipient address `%s'\n"),
1011 ctl->listener, address);
1017 if (force_transient_error) {
1018 /* do not risk dataloss due to overengineered multidrop
1019 * crap. If one of the recipients returned PS_TRANSIENT,
1020 * we return exactly that.
1022 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
1023 return(PS_TRANSIENT);
1025 #ifdef EXPLICIT_BOUNCE_ON_BAD_ADDRESS
1027 * This should not be necessary, because the SMTP listener itself
1028 * should genrate a bounce for the bad address.
1031 send_bouncemail(ctl, msg, XMIT_RCPTBAD,
1032 "Some addresses were rejected by the MDA fetchmail forwards to.\r\n",
1033 *bad_addresses, from_responses);
1034 #endif /* EXPLICIT_BOUNCE_ON_BAD_ADDRESS */
1037 * It's tempting to do local notification only if bouncemail was
1038 * insufficient -- that is, to add && total_addresses > *bad_addresses
1039 * to the test here. The problem with this theory is that it would
1040 * make initial diagnosis of a broken multidrop configuration very
1041 * hard -- most single-recipient messages would just invisibly bounce.
1043 if (!(*good_addresses))
1045 if (!run.postmaster[0])
1047 if (outlevel >= O_VERBOSE)
1048 report(stderr, GT_("no address matches; no postmaster set.\n"));
1049 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
1052 if ((smtp_err = SMTP_rcpt(ctl->smtp_socket,
1053 rcpt_address (ctl, run.postmaster, 0))) == SM_UNRECOVERABLE)
1056 return(PS_TRANSIENT);
1058 if (smtp_err != SM_OK)
1060 report(stderr, GT_("can't even send to %s!\n"), run.postmaster);
1061 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
1065 if (outlevel >= O_VERBOSE)
1066 report(stderr, GT_("no address matches; forwarding to %s.\n"), run.postmaster);
1070 * Tell the listener we're ready to send data.
1071 * Some listeners (like zmailer) may return antispam errors here.
1073 if ((smtp_err = SMTP_data(ctl->smtp_socket)) == SM_UNRECOVERABLE)
1076 return(PS_TRANSIENT);
1078 if (smtp_err != SM_OK)
1080 int err = handle_smtp_report(ctl, msg);
1081 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1086 * We need to stash this away in order to know how many
1087 * response lines to expect after the LMTP end-of-message.
1089 lmtp_responses = *good_addresses;
1094 static int open_mda_sink(struct query *ctl, struct msgblk *msg,
1095 int *good_addresses, int *bad_addresses)
1096 /* open a stream to a local MDA */
1100 #endif /* HAVE_SETEUID */
1102 int length = 0, fromlen = 0, nameslen = 0;
1103 char *names = NULL, *before, *after, *from = NULL;
1105 ctl->destaddr = "localhost";
1107 for (idp = msg->recipients; idp; idp = idp->next)
1108 if (idp->val.status.mark == XMIT_ACCEPT)
1109 (*good_addresses)++;
1111 length = strlen(ctl->mda);
1112 before = xstrdup(ctl->mda);
1114 /* get user addresses for %T (or %s for backward compatibility) */
1115 if (strstr(before, "%s") || strstr(before, "%T"))
1118 * We go through this in order to be able to handle very
1119 * long lists of users and (re)implement %s.
1122 for (idp = msg->recipients; idp; idp = idp->next)
1123 if ((idp->val.status.mark == XMIT_ACCEPT))
1124 nameslen += (strlen(idp->id) + 1); /* string + ' ' */
1125 if ((*good_addresses == 0))
1126 nameslen = strlen(run.postmaster);
1128 names = (char *)xmalloc(nameslen + 1); /* account for '\0' */
1129 if (*good_addresses == 0)
1130 strcpy(names, run.postmaster);
1134 for (idp = msg->recipients; idp; idp = idp->next)
1135 if (idp->val.status.mark == XMIT_ACCEPT)
1137 strcat(names, idp->id);
1140 names[--nameslen] = '\0'; /* chop trailing space */
1146 /* get From address for %F */
1147 if (strstr(before, "%F"))
1149 from = xstrdup(msg->return_path);
1153 fromlen = strlen(from);
1156 /* do we have to build an mda string? */
1161 /* find length of resulting mda string */
1163 while ((sp = strstr(sp, "%s"))) {
1164 length += nameslen; /* subtract %s and add '' */
1168 while ((sp = strstr(sp, "%T"))) {
1169 length += nameslen; /* subtract %T and add '' */
1173 while ((sp = strstr(sp, "%F"))) {
1174 length += fromlen; /* subtract %F and add '' */
1178 after = xmalloc(length + 1);
1180 /* copy mda source string to after, while expanding %[sTF] */
1181 for (dp = after, sp = before; (*dp = *sp); dp++, sp++) {
1182 if (sp[0] != '%') continue;
1184 /* need to expand? BTW, no here overflow, because in
1185 ** the worst case (end of string) sp[1] == '\0' */
1186 if (sp[1] == 's' || sp[1] == 'T') {
1191 sp++; /* position sp over [sT] */
1192 dp--; /* adjust dp */
1193 } else if (sp[1] == 'F') {
1198 sp++; /* position sp over F */
1199 dp--; /* adjust dp */
1218 if (outlevel >= O_DEBUG)
1219 report(stdout, GT_("about to deliver with: %s\n"), before);
1223 * Arrange to run with user's permissions if we're root.
1224 * This will initialize the ownership of any files the
1225 * MDA creates properly. (The seteuid call is available
1226 * under all BSDs and Linux)
1228 orig_uid = getuid();
1230 #endif /* HAVE_SETEUID */
1232 sinkfp = popen(before, "w");
1237 /* this will fail quietly if we didn't start as root */
1239 #endif /* HAVE_SETEUID */
1243 report(stderr, GT_("MDA open failed\n"));
1248 * We need to disable the normal SIGCHLD handling here because
1249 * sigchld_handler() would reap away the error status, returning
1250 * error status instead of 0 for successful completion.
1252 set_signal_handler(SIGCHLD, SIG_DFL);
1257 int open_sink(struct query *ctl, struct msgblk *msg,
1258 int *good_addresses, int *bad_addresses)
1259 /* set up sinkfp to be an input sink we can ship a message to */
1261 *bad_addresses = *good_addresses = 0;
1263 if (ctl->bsmtp) /* dump to a BSMTP batch file */
1264 return(open_bsmtp_sink(ctl, msg, good_addresses, bad_addresses));
1266 * Try to forward to an SMTP or LMTP listener. If the attempt to
1267 * open a socket fails, fall through to attempt delivery via
1270 else if (!ctl->mda && smtp_open(ctl) != -1)
1271 return(open_smtp_sink(ctl, msg, good_addresses, bad_addresses));
1274 * Awkward case. User didn't specify an MDA. Our attempt to get a
1275 * listener socket failed. Try to cope anyway -- initial configuration
1276 * may have found procmail.
1280 report(stderr, GT_("%cMTP connect to %s failed\n"),
1282 ctl->smtphost ? ctl->smtphost : "localhost");
1284 #ifndef FALLBACK_MDA
1285 /* No fallback MDA declared. Bail out. */
1289 * If user had things set up to forward offsite, no way
1290 * we want to deliver locally!
1292 if (ctl->smtphost && strcmp(ctl->smtphost, "localhost"))
1296 * User was delivering locally. We have a fallback MDA.
1297 * Latch it in place, logging the error, and fall through.
1298 * Set stripcr as we would if MDA had been the initial transport
1300 ctl->mda = FALLBACK_MDA;
1302 ctl->stripcr = TRUE;
1304 report(stderr, GT_("can't raise the listener; falling back to %s"),
1309 if (ctl->mda) /* must deliver through an MDA */
1310 return(open_mda_sink(ctl, msg, good_addresses, bad_addresses));
1315 void release_sink(struct query *ctl)
1316 /* release the per-message output sink, whether it's a pipe or SMTP socket */
1318 if (ctl->bsmtp && sinkfp)
1320 if (strcmp(ctl->bsmtp, "-"))
1323 sinkfp = (FILE *)NULL;
1331 sinkfp = (FILE *)NULL;
1333 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1337 int close_sink(struct query *ctl, struct msgblk *msg, flag forward)
1338 /* perform end-of-message actions on the current output sink */
1345 /* close the delivery pipe, we'll reopen before next message */
1348 rc = pclose(sinkfp);
1349 sinkfp = (FILE *)NULL;
1354 deal_with_sigchld(); /* Restore SIGCHLD handling to reap zombies */
1358 if (WIFSIGNALED(rc)) {
1360 GT_("MDA died of signal %d\n"), WTERMSIG(rc));
1361 } else if (WIFEXITED(rc)) {
1363 GT_("MDA returned nonzero status %d\n"), WEXITSTATUS(rc));
1366 GT_("Strange: MDA pclose returned %d, cannot handle at %s:%d\n"), rc, __FILE__, __LINE__);
1372 else if (ctl->bsmtp && sinkfp)
1376 /* implicit disk-full check here... */
1377 fputs(".\r\n", sinkfp);
1378 error = ferror(sinkfp);
1379 if (strcmp(ctl->bsmtp, "-"))
1381 if (fclose(sinkfp) == EOF) error = 1;
1382 sinkfp = (FILE *)NULL;
1387 GT_("Message termination or close of BSMTP file failed\n"));
1393 /* write message terminator */
1394 if ((smtp_err = SMTP_eom(ctl->smtp_socket)) == SM_UNRECOVERABLE)
1399 if (smtp_err != SM_OK)
1401 if (handle_smtp_report(ctl, msg) != PS_REFUSED)
1403 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1408 report(stderr, GT_("SMTP listener refused delivery\n"));
1409 SMTP_rset(ctl->smtp_socket); /* stay on the safe side */
1415 * If this is an SMTP connection, SMTP_eom() ate the response.
1416 * But could be this is an LMTP connection, in which case we have to
1417 * interpret either (a) a single 503 response meaning there
1418 * were no successful RCPT TOs, or (b) a variable number of
1419 * responses, one for each successful RCPT TO. We need to send
1420 * bouncemail on each failed response and then return TRUE anyway,
1421 * otherwise the message will get left in the queue and resent
1422 * to people who got it the first time.
1424 if (ctl->listener == LMTP_MODE)
1426 if (lmtp_responses == 0)
1428 SMTP_ok(ctl->smtp_socket);
1431 * According to RFC2033, 503 is the only legal response
1432 * if no RCPT TO commands succeeded. No error recovery
1433 * is really possible here, as we have no idea what
1434 * insane thing the listener might be doing if it doesn't
1437 if (atoi(smtp_response) == 503)
1438 report(stderr, GT_("LMTP delivery error on EOM\n"));
1441 GT_("Unexpected non-503 response to LMTP EOM: %s\n"),
1445 * It's not completely clear what to do here. We choose to
1446 * interpret delivery failure here as a transient error,
1447 * the same way SMTP delivery failure is handled. If we're
1448 * wrong, an undead message will get stuck in the queue.
1457 /* eat the RFC2033-required responses, saving errors */
1458 xalloca(responses, char **, sizeof(char *) * lmtp_responses);
1459 for (errors = i = 0; i < lmtp_responses; i++)
1461 if ((smtp_err = SMTP_ok(ctl->smtp_socket)) == SM_UNRECOVERABLE)
1466 if (smtp_err == SM_OK)
1467 responses[i] = (char *)NULL;
1470 xalloca(responses[errors],
1472 strlen(smtp_response)+1);
1473 strcpy(responses[errors], smtp_response);
1479 return(TRUE); /* all deliveries succeeded */
1482 * One or more deliveries failed.
1483 * If we can bounce a failures list back to the
1484 * sender, and the postmaster does not want to
1485 * deal with the bounces return TRUE, deleting the
1486 * message from the server so it won't be
1487 * re-forwarded on subsequent poll cycles.
1489 return(send_bouncemail(ctl, msg, XMIT_ACCEPT,
1490 "LSMTP partial delivery failure.\r\n",
1491 errors, responses));
1499 int open_warning_by_mail(struct query *ctl, struct msgblk *msg)
1500 /* set up output sink for a mailed warning to calling user */
1505 * Dispatching warning email is a little complicated. The problem is
1506 * that we have to deal with three distinct cases:
1508 * 1. Single-drop running from user account. Warning mail should
1509 * go to the local name for which we're collecting (coincides
1510 * with calling user).
1512 * 2. Single-drop running from root or other privileged ID, with rc
1513 * file generated on the fly (Ken Estes's weird setup...) Mail
1514 * should go to the local name for which we're collecting (does not
1515 * coincide with calling user).
1517 * 3. Multidrop. Mail must go to postmaster. We leave the recipients
1518 * member null so this message will fall through to run.postmaster.
1520 * The zero in the reallen element means we won't pass a SIZE
1521 * option to ESMTP; the message length would be more trouble than
1522 * it's worth to compute.
1524 struct msgblk reply = {NULL, NULL, "FETCHMAIL-DAEMON@", 0, 0};
1527 strcat(reply.return_path, ctl->smtpaddress ? ctl->smtpaddress :
1530 if (!MULTIDROP(ctl)) /* send to calling user */
1532 save_str(&reply.recipients, ctl->localnames->id, XMIT_ACCEPT);
1533 status = open_sink(ctl, &reply, &good, &bad);
1534 free_str_list(&reply.recipients);
1536 else /* send to postmaster */
1537 status = open_sink(ctl, &reply, &good, &bad);
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\"", nl_langinfo(CODESET));
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 #if defined(HAVE_STDARG_H)
1552 void stuff_warning(const char *rfc2047charset, struct query *ctl, const char *fmt, ... )
1554 void stuff_warning(rfc2047charset, ctl, fmt, va_alist)
1555 const char *charset;
1557 const char *fmt; /* printf-style format */
1561 /* make huge -- i18n can bulk up error messages a lot */
1562 char buf[2*MSGBUFSIZE+4];
1566 * stuffline() requires its input to be writeable (for CR stripping),
1567 * so we needed to copy the message to a writeable buffer anyway in
1568 * case it was a string constant. We make a virtue of that necessity
1569 * here by supporting stdargs/varargs.
1571 #if defined(HAVE_STDARG_H)
1576 #ifdef HAVE_VSNPRINTF
1577 vsnprintf(buf, sizeof(buf), fmt, ap);
1579 vsprintf(buf, fmt, ap);
1583 #ifdef HAVE_SNPRINTF
1584 snprintf(buf+strlen(buf), sizeof(buf)-strlen(buf), "\r\n");
1586 strcat(buf, "\r\n");
1587 #endif /* HAVE_SNPRINTF */
1589 /* guard against very long lines */
1590 buf[MSGBUFSIZE+1] = '\r';
1591 buf[MSGBUFSIZE+2] = '\n';
1592 buf[MSGBUFSIZE+3] = '\0';
1594 stuffline(ctl, rfc2047charset != NULL ? rfc2047e(buf, rfc2047charset) : buf);
1597 void close_warning_by_mail(struct query *ctl, struct msgblk *msg)
1598 /* sign and send mailed warnings */
1600 stuff_warning(NULL, ctl, GT_("-- \nThe Fetchmail Daemon"));
1601 close_sink(ctl, msg, TRUE);
1604 /* sink.c ends here */