2 * driver.c -- generic driver for mail fetch method protocols
4 * Copyright 1997 by Eric S. Raymond
5 * For license terms, see the file COPYING in this directory.
14 #if defined(STDC_HEADERS)
17 #if defined(HAVE_UNISTD_H)
20 #if defined(HAVE_STDARG_H)
25 #if defined(HAVE_ALLOCA_H)
28 #if defined(HAVE_SYS_ITIMER_H)
29 #include <sys/itimer.h>
34 #ifdef HAVE_GETHOSTBYNAME
37 #endif /* HAVE_GETHOSTBYNAME */
44 #if defined (__bsdi__)
45 #include <des.h> /* order of includes matters */
47 #define krb_get_err_text(e) (krb_err_txt[e])
49 #if defined(__FreeBSD__)
50 #define krb_get_err_text(e) (krb_err_txt[e])
56 #endif /* ! defined (__FreeBSD__) */
57 #endif /* ! defined (__bsdi__) */
58 #include <netinet/in.h>
60 #endif /* KERBEROS_V4 */
61 #include "fetchmail.h"
65 /* BSD portability hack...I know, this is an ugly place to put it */
66 #if !defined(SIGCHLD) && defined(SIGCLD)
67 #define SIGCHLD SIGCLD
70 #define SMTP_PORT 25 /* standard SMTP service port */
72 extern char *strstr(); /* needed on sysV68 R3V7.1. */
74 int fetchlimit; /* how often to tear down the server connection */
75 int batchcount; /* count of messages sent in current batch */
76 flag peek_capable; /* can we peek for better error recovery? */
78 static const struct method *protocol;
79 static jmp_buf restart;
83 #define GENSYM (sprintf(tag, "a%04d", ++tagnum), tag)
85 static char *shroud; /* string to shroud in debug output, if non-NULL */
86 static int mytimeout; /* value of nonreponse timeout */
88 static void set_timeout(int timeleft)
89 /* reset the nonresponse-timeout */
91 struct itimerval ntimeout;
93 ntimeout.it_interval.tv_sec = ntimeout.it_interval.tv_usec = 0;
94 ntimeout.it_value.tv_sec = timeleft;
95 ntimeout.it_value.tv_usec = 0;
96 setitimer(ITIMER_REAL, &ntimeout, (struct itimerval *)NULL);
99 static void timeout_handler (int signal)
100 /* handle server-timeout SIGALRM signal */
105 #define XMIT_ACCEPT 1
106 #define XMIT_REJECT 2
107 #define XMIT_ANTISPAM 3
108 static int accept_count, reject_count;
110 #ifdef HAVE_RES_SEARCH
113 static int is_host_alias(const char *name, struct query *ctl)
114 /* determine whether name is a DNS alias of the hostname */
117 struct mxentry *mxp, *mxrecords;
119 struct hostdata *lead_server =
120 ctl->server.lead_server ? ctl->server.lead_server : &ctl->server;
123 * The first two checks are optimizations that will catch a good
126 * (1) check against the `true name' deduced from the poll label
127 * and the via option (if present) at the beginning of the poll cycle.
128 * Odds are good this will either be the mailserver's FQDN or a suffix of
129 * it with the mailserver's domain's default host name omitted.
131 * (2) Then check the rest of the `also known as'
132 * cache accumulated by previous DNS checks. This cache is primed
133 * by the aka list option.
135 * Any of these on a mail address is definitive. Only if the
136 * name doesn't match any is it time to call the bind library.
137 * If this happens odds are good we're looking at an MX name.
139 if (strcmp(lead_server->truename, name) == 0)
141 else if (str_in_list(&lead_server->akalist, name))
143 else if (!ctl->server.dns)
147 * We know DNS service was up at the beginning of this poll cycle.
148 * If it's down, our nameserver has crashed. We don't want to try
149 * delivering the current message or anything else from this
150 * mailbox until it's back up.
152 else if ((he = gethostbyname(name)) != (struct hostent *)NULL)
154 if (strcmp(ctl->server.truename, he->h_name) == 0)
162 case HOST_NOT_FOUND: /* specified host is unknown */
163 case NO_ADDRESS: /* valid, but does not have an IP address */
166 case NO_RECOVERY: /* non-recoverable name server error */
167 case TRY_AGAIN: /* temporary error on authoritative server */
169 if (outlevel != O_SILENT)
170 putchar('\n'); /* terminate the progress message */
172 "nameserver failure while looking for `%s' during poll of %s.",
173 name, ctl->server.pollname);
179 * We're only here if DNS was OK but the gethostbyname() failed
180 * with a HOST_NOT_FOUND or NO_ADDRESS error.
181 * Search for a name match on MX records pointing to the server.
184 if ((mxrecords = getmxrecords(name)) == (struct mxentry *)NULL)
188 case HOST_NOT_FOUND: /* specified host is unknown */
189 case NO_ADDRESS: /* valid, but does not have an IP address */
193 case NO_RECOVERY: /* non-recoverable name server error */
194 case TRY_AGAIN: /* temporary error on authoritative server */
197 "nameserver failure while looking for `%s' during poll of %s.",
198 name, ctl->server.pollname);
205 for (mxp = mxrecords; mxp->name; mxp++)
206 if (strcmp(ctl->server.truename, mxp->name) == 0)
212 /* add this name to relevant server's `also known as' list */
213 save_str(&lead_server->akalist, -1, name);
217 static void map_name(name, ctl, xmit_names)
218 /* add given name to xmit_names if it matches declared localnames */
219 const char *name; /* name to map */
220 struct query *ctl; /* list of permissible aliases */
221 struct idlist **xmit_names; /* list of recipient names parsed out */
225 lname = idpair_find(&ctl->localnames, name);
226 if (!lname && ctl->wildcard)
229 if (lname != (char *)NULL)
231 if (outlevel == O_VERBOSE)
232 error(0, 0, "mapped %s to local %s", name, lname);
233 save_str(xmit_names, XMIT_ACCEPT, lname);
238 void find_server_names(hdr, ctl, xmit_names)
239 /* parse names out of a RFC822 header into an ID list */
240 const char *hdr; /* RFC822 header in question */
241 struct query *ctl; /* list of permissible aliases */
242 struct idlist **xmit_names; /* list of recipient names parsed out */
244 if (hdr == (char *)NULL)
250 if ((cp = nxtaddr(hdr)) != (char *)NULL)
254 if ((atsign = strchr(cp, '@')))
259 * Does a trailing segment of the hostname match something
260 * on the localdomains list? If so, save the whole name
263 for (idp = ctl->server.localdomains; idp; idp = idp->next)
267 rhs = atsign + (strlen(atsign) - strlen(idp->id));
268 if ((rhs[-1] == '.' || rhs[-1] == '@')
269 && strcasecmp(rhs, idp->id) == 0)
271 if (outlevel == O_VERBOSE)
272 error(0, 0, "passed through %s matching %s",
274 save_str(xmit_names, XMIT_ACCEPT, cp);
281 * Check to see if the right-hand part is an alias
282 * or MX equivalent of the mailserver. If it's
283 * not, skip this name. If it is, we'll keep
284 * going and try to find a mapping to a client name.
286 if (!is_host_alias(atsign+1, ctl))
288 save_str(xmit_names, XMIT_REJECT, cp);
295 map_name(cp, ctl, xmit_names);
297 ((cp = nxtaddr((char *)NULL)) != (char *)NULL);
301 static char *parse_received(struct query *ctl, char *bufp)
302 /* try to extract real addressee from the Received line */
305 static char rbuf[HOSTLEN + USERNAMELEN + 4];
308 * Try to extract the real envelope addressee. We look here
309 * specifically for the mailserver's Received line.
310 * Note: this will only work for sendmail, or an MTA that
311 * shares sendmail's convention for embedding the envelope
312 * address in the Received line. Sendmail itself only
313 * does this when the mail has a single recipient.
315 if ((ok = strstr(bufp, "by ")) == (char *)NULL)
321 /* extract space-delimited token after "by " */
322 for (sp = ok + 3; isspace(*sp); sp++)
325 for (; !isspace(*sp); sp++)
330 * If it's a DNS name of the mail server, look for the
331 * recipient name after a following "for". Otherwise
334 if (is_host_alias(rbuf, ctl))
335 ok = strstr(sp, "for ");
348 while (*sp && *sp != '>' && *sp != '@' && *sp != ';')
353 /* uh oh -- whitespace here can't be right! */
364 if (outlevel == O_VERBOSE)
365 error(0, 0, "found Received address `%s'", rbuf);
369 #endif /* HAVE_RES_SEARCH */
371 static int smtp_open(struct query *ctl)
372 /* try to open a socket to the appropriate SMTP server for this query */
374 /* maybe it's time to close the socket in order to force delivery */
375 if (ctl->batchlimit > 0 && (ctl->smtp_socket != -1) && batchcount++ == ctl->batchlimit)
377 close(ctl->smtp_socket);
378 ctl->smtp_socket = -1;
382 /* if no socket to any SMTP host is already set up, try to open one */
383 if (ctl->smtp_socket == -1)
386 * RFC 1123 requires that the domain name in HELO address is a
387 * "valid principal domain name" for the client host. We
388 * violate this with malice aforethought in order to make the
389 * Received headers and logging look right.
391 * In fact this code relies on the RFC1123 requirement that the
392 * SMTP listener must accept messages even if verification of the
393 * HELO name fails (RFC1123 section 5.2.5, paragraph 2).
395 * How we compute the true mailhost name to pass to the
396 * listener doesn't affect behavior on RFC1123- violating
397 * listener that check for name match; we're going to lose
398 * on those anyway because we can never give them a name
399 * that matches the local machine fetchmail is running on.
400 * What it will affect is the listener's logging.
404 /* run down the SMTP hunt list looking for a server that's up */
405 for (idp = ctl->smtphunt; idp; idp = idp->next)
407 ctl->smtphost = idp->id; /* remember last host tried. */
409 if ((ctl->smtp_socket = SockOpen(idp->id,SMTP_PORT)) == -1)
412 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
413 SMTP_ehlo(ctl->smtp_socket,
414 ctl->server.truename,
415 &ctl->server.esmtp_options) == SM_OK)
419 * RFC 1869 warns that some listeners hang up on a failed EHLO,
420 * so it's safest not to assume the socket will still be good.
422 close(ctl->smtp_socket);
423 ctl->smtp_socket = -1;
425 /* if opening for ESMTP failed, try SMTP */
426 if ((ctl->smtp_socket = SockOpen(idp->id,SMTP_PORT)) == -1)
429 if (SMTP_ok(ctl->smtp_socket) == SM_OK &&
430 SMTP_helo(ctl->smtp_socket, ctl->server.truename) == SM_OK)
433 close(ctl->smtp_socket);
434 ctl->smtp_socket = -1;
438 return(ctl->smtp_socket);
441 /* these are shared by stuffline, readheaders and readbody */
443 static RETSIGTYPE (*sigchld)();
444 static int sizeticker;
446 static int stuffline(struct query *ctl, char *buf, flag delimited)
447 /* ship a line to the given control block's SMTP server */
451 /* fix message lines that have only \n termination (for qmail) */
454 char *cp = buf + strlen(buf) - 1;
456 if (*cp == '\n' && (cp == buf || cp[-1] != '\r'))
465 * SMTP byte-stuffing. We only do this if the protocol does *not*
466 * use .<CR><LF> as EOM. If it does, the server will already have
467 * decorated any . lines it sends back up.
469 if (!delimited && *buf == '.')
470 if (sinkfp && ctl->mda)
472 else if (ctl->smtp_socket != -1)
473 SockWrite(ctl->smtp_socket, buf, 1);
475 /* we may need to strip carriage returns */
480 for (sp = tp = buf; *sp; sp++)
488 n = fwrite(buf, 1, strlen(buf), sinkfp);
489 else if (ctl->smtp_socket != -1)
490 n = SockWrite(ctl->smtp_socket, buf, strlen(buf));
495 static int readheaders(sock, len, ctl, realname, num)
496 /* read message headers and ship to SMTP or MDA */
497 int sock; /* to which the server is connected */
498 long len; /* length of message */
499 struct query *ctl; /* query control record */
500 char *realname; /* real name of host */
501 int num; /* index of message */
506 struct addrblk *next;
507 } *addrchain = NULL, **chainptr = &addrchain;
508 char buf[MSGBUFSIZE+1], return_path[MSGBUFSIZE+1];
509 int from_offs, ctt_offs, env_offs, next_address;
510 char *headers, *received_for;
511 int n, linelen, oldlen, ch, remaining;
513 struct idlist *idp, *xmit_names;
514 flag good_addresses, bad_addresses, has_nuls;
515 #ifdef HAVE_RES_SEARCH
516 flag no_local_matches = FALSE;
517 #endif /* HAVE_RES_SEARCH */
520 next_address = sizeticker = 0;
522 return_path[0] = '\0';
523 olderrs = ctl->errcount;
525 /* read message headers */
526 headers = received_for = NULL;
527 from_offs = ctt_offs = env_offs = -1;
529 for (remaining = len; remaining > 0; remaining -= linelen)
533 line = xmalloc(sizeof(buf));
537 if ((n = SockRead(sock, buf, sizeof(buf)-1)) == -1)
541 /* lines may not be properly CRLF terminated; fix this for qmail */
544 cp = buf + strlen(buf) - 1;
545 if (*cp == '\n' && (cp == buf || cp[-1] != '\r'))
553 set_timeout(ctl->server.timeout);
554 /* leave extra room for reply_hack to play with */
555 line = (char *) realloc(line, strlen(line) + strlen(buf) + HOSTLEN + 1);
557 if (line[0] == '\r' && line[1] == '\n')
560 /* we may need to grab RFC822 continuations */
561 ((ch = SockPeek(sock)) == ' ' || ch == '\t');
563 /* write the message size dots */
564 if ((outlevel > O_SILENT && outlevel < O_VERBOSE) && linelen > 0)
566 sizeticker += linelen;
567 while (sizeticker >= SIZETICKER)
570 sizeticker -= SIZETICKER;
574 if (linelen != strlen(line))
577 /* check for end of headers; don't save terminating line */
578 if (line[0] == '\r' && line[1] == '\n')
584 /* maybe this is a special message that holds mailbox annotations? */
585 if (protocol->retain_hdr && protocol->retain_hdr(num, line))
589 * This code prevents fetchmail from becoming an accessory after
590 * the fact to upstream sendmails with the `E' option on. This
591 * can result in an escaped Unix From_ line at the beginning of
592 * the headers. If fetchmail just passes it through, the client
593 * listener may think the message has *no* headers (since the first)
594 * line it sees doesn't look RFC822-conformant) and fake up a set.
596 * What the user would see in this case is bogus (synthesized)
597 * headers, followed by a blank line, followed by the >From,
598 * followed by the real headers, followed by a blank line,
601 * We forestall this lossage by tossing anything that looks
602 * like an escaped From_ line in headers. These aren't RFC822
603 * so our conscience is clear...
605 if (!strncasecmp(line, ">From ", 6))
612 * If we see a Status line, it may have been inserted by an MUA
613 * on the mail host, or it may have been inserted by the server
614 * program after the headers in the transaction stream. This
615 * can actually hose some new-mail notifiers such as xbuffy,
616 * which assumes any Status line came from a *local* MDA and
617 * therefore indicates that the message has been seen.
619 * Some buggy POP servers (including at least the 3.3(20)
620 * version of the one distributed with IMAP) insert empty
621 * Status lines in the transaction stream; we'll chuck those
622 * unconditionally. Nonempty ones get chucked if the user
623 * turns on the dropstatus flag.
625 if (!strncasecmp(line, "Status:", 7))
629 for (cp = line + 7; *cp && isspace(*cp); cp++)
632 if (!*cp || ctl->dropstatus)
640 * OK, this is messy. If we're forwarding by SMTP, it's the
641 * SMTP-receiver's job (according to RFC821, page 22, section
642 * 4.1.1) to generate a Return-Path line on final delivery.
643 * The trouble is, we've already got one because the
644 * mailserver's SMTP thought *it* was responsible for final
647 * Stash away the contents of Return-Path for use in generating
648 * MAIL FROM later on, then prevent the header from being saved
649 * with the others. In effect, we strip it off here.
651 * If the SMTP server conforms to the standards, and fetchmail gets the
652 * envelope sender from the Return-Path, the new Return-Path should be
653 * exactly the same as the original one.
655 if (!ctl->mda && !strncasecmp("Return-Path:", line, 12))
657 strcpy(return_path, nxtaddr(line));
663 reply_hack(line, realname);
667 oldlen = strlen(line);
668 headers = xmalloc(oldlen + 1);
669 (void) strcpy(headers, line);
677 newlen = oldlen + strlen(line);
678 headers = (char *) realloc(headers, newlen + 1);
681 strcpy(headers + oldlen, line);
683 line = headers + oldlen;
687 if (from_offs == -1 && !strncasecmp("From:", line, 5))
688 from_offs = (line - headers);
689 else if (from_offs == -1 && !strncasecmp("Resent-From:", line, 12))
690 from_offs = (line - headers);
691 else if (from_offs == -1 && !strncasecmp("Apparently-From:", line, 16))
692 from_offs = (line - headers);
693 else if (!strncasecmp("Content-Transfer-Encoding:", line, 26))
694 ctt_offs = (line - headers);
695 else if (!strncasecmp("Message-Id:", buf, 11 ))
697 if( ctl->server.uidl )
700 sscanf( buf+12, "%s", id);
701 if( !str_in_list( &ctl->newsaved, id ) )
702 save_str(&ctl->newsaved, num, id );
706 else if (!MULTIDROP(ctl))
709 else if (!strncasecmp("To:", line, 3)
710 || !strncasecmp("Cc:", line, 3)
711 || !strncasecmp("Bcc:", line, 4))
713 *chainptr = xmalloc(sizeof(struct addrblk));
714 (*chainptr)->offset = (line - headers);
715 chainptr = &(*chainptr)->next;
719 else if (ctl->server.envelope != STRING_DISABLED)
721 if (ctl->server.envelope
722 && strcasecmp(ctl->server.envelope, "received"))
724 if (env_offs == -1 && !strncasecmp(ctl->server.envelope,
726 strlen(ctl->server.envelope)))
727 env_offs = (line - headers);
729 #ifdef HAVE_RES_SEARCH
730 else if (!received_for && !strncasecmp("Received:", line, 9))
731 received_for = parse_received(ctl, line);
732 #endif /* HAVE_RES_SEARCH */
737 * Hack time. If the first line of the message was blank, with no headers
738 * (this happens occasionally due to bad gatewaying software) cons up
739 * a set of fake headers.
741 * If you modify the fake header template below, be sure you don't
742 * make either From or To address @-less, otherwise the reply_hack
743 * logic will do bad things.
745 if (headers == (char *)NULL)
748 "From: <FETCHMAIL-DAEMON@%s>\r\nTo: %s@localhost\r\nSubject: Headerless mail from %s's mailbox on %s\r\n",
749 fetchmailhost, user, ctl->remotename, realname);
750 headers = xstrdup(buf);
754 * We can now process message headers before reading the text.
755 * In fact we have to, as this will tell us where to forward to.
758 /* cons up a list of local recipients */
759 xmit_names = (struct idlist *)NULL;
760 bad_addresses = good_addresses = accept_count = reject_count = 0;
761 #ifdef HAVE_RES_SEARCH
762 /* is this a multidrop box? */
765 if (env_offs > -1) /* We have the actual envelope addressee */
766 find_server_names(headers + env_offs, ctl, &xmit_names);
767 else if (received_for)
769 * We have the Received for addressee.
770 * It has to be a mailserver address, or we
771 * wouldn't have got here.
773 map_name(received_for, ctl, &xmit_names);
779 * We haven't extracted the envelope address.
780 * So check all the header addresses.
784 register struct addrblk *nextptr;
786 find_server_names(headers+addrchain->offset, ctl, &xmit_names);
787 nextptr = addrchain->next;
794 no_local_matches = TRUE;
795 save_str(&xmit_names, XMIT_ACCEPT, user);
796 if (outlevel == O_VERBOSE)
798 "no local matches, forwarding to %s",
802 else /* it's a single-drop box, use first localname */
803 #endif /* HAVE_RES_SEARCH */
804 save_str(&xmit_names, XMIT_ACCEPT, ctl->localnames->id);
808 * Time to either address the message or decide we can't deliver it yet.
810 if (ctl->errcount > olderrs) /* there were DNS errors above */
812 if (outlevel == O_VERBOSE)
813 error(0,0, "forwarding and deletion suppressed due to DNS errors");
815 return(PS_TRANSIENT);
817 else if (ctl->mda) /* we have a declared MDA */
823 * We go through this in order to be able to handle very
824 * long lists of users and (re)implement %s.
826 for (idp = xmit_names; idp; idp = idp->next)
827 if (idp->val.num == XMIT_ACCEPT)
828 length += (strlen(idp->id) + 1);
829 names = (char *)alloca(length);
831 for (idp = xmit_names; idp; idp = idp->next)
832 if (idp->val.num == XMIT_ACCEPT)
834 strcat(names, idp->id);
837 cmd = (char *)alloca(strlen(ctl->mda) + length);
838 sprintf(cmd, ctl->mda, names);
839 if (outlevel == O_VERBOSE)
840 error(0, 0, "about to deliver with: %s", cmd);
844 * Arrange to run with user's permissions if we're root.
845 * This will initialize the ownership of any files the
846 * MDA creates properly. (The seteuid call is available
847 * under all BSDs and Linux)
850 #endif /* HAVE_SETEUID */
852 sinkfp = popen(cmd, "w");
855 /* this will fail quietly if we didn't start as root */
857 #endif /* HAVE_SETEUID */
861 error(0, -1, "MDA open failed");
865 sigchld = signal(SIGCHLD, SIG_DFL);
869 char *ap, *ctt, options[MSGBUFSIZE], addr[128];
871 /* build a connection to the SMTP listener */
872 if ((smtp_open(ctl) == -1))
874 free_str_list(&xmit_names);
875 error(0, -1, "SMTP connect to %s failed",
876 ctl->smtphost ? ctl->smtphost : "localhost");
881 * Compute ESMTP options. It's a kluge to use nxtaddr()
882 * here because the contents of the Content-Transfer-Encoding
883 * headers isn't semantically an address. But it has the
884 * desired tokenizing effect.
887 if (ctl->server.esmtp_options & ESMTP_8BITMIME)
889 sprintf(options, " BODY=8BITMIME");
890 else if ((ctt_offs >= 0) && (ctt = nxtaddr(headers + ctt_offs)))
892 if (!strcasecmp(ctt,"7BIT"))
893 sprintf(options, " BODY=7BIT");
894 else if (!strcasecmp(ctt,"8BIT"))
895 sprintf(options, " BODY=8BITMIME");
897 if ((ctl->server.esmtp_options & ESMTP_SIZE))
898 sprintf(options + strlen(options), " SIZE=%ld", len);
901 * If there is a Return-Path address on the message, this was
902 * almost certainly the MAIL FROM address given the originating
903 * sendmail. This is the best thing to use for logging the
904 * message origin (it sets up the right behavior for bounces and
905 * mailing lists). Otherwise, take the From address.
907 * Try to get the SMTP listener to take the Return-Path or
908 * From address as MAIL FROM . If it won't, fall back on the
909 * calling-user ID. This won't affect replies, which use the
910 * header From address anyway.
912 * RFC 1123 requires that the domain name part of the
913 * MAIL FROM address be "canonicalized", that is a
914 * FQDN or MX but not a CNAME. We'll assume the From
915 * header is already in this form here (it certainly
916 * is if rewrite is on). RFC 1123 is silent on whether
917 * a nonexistent hostname part is considered canonical.
919 * This is a potential problem if the MTAs further upstream
920 * didn't pass canonicalized From/Return-Path lines, *and* the
921 * local SMTP listener insists on them.
926 else if (from_offs == -1 || !(ap = nxtaddr(headers + from_offs)))
928 if (SMTP_from(ctl->smtp_socket, ap, options) != SM_OK)
930 int smtperr = atoi(smtp_response);
933 * Suppress error message only if the response specifically
934 * means `excluded for policy reasons'. We *should* see
935 * an error when the return code is less specific.
937 if (smtperr >= 400 && smtperr != 571)
938 error(0, -1, "SMTP error: %s", smtp_response);
942 case 571: /* sendmail's "unsolicited email refused" */
943 case 501: /* exim's old antispam response */
944 case 550: /* exim's new antispam response (temporary) */
946 * SMTP listener explicitly refuses to deliver
947 * mail coming from this address, probably due
948 * to an anti-spam domain exclusion. Respect
949 * this. Don't try to ship the message, and
950 * don't prevent it from being deleted.
955 case 452: /* insufficient system storage */
957 * Temporary out-of-queue-space condition on the
958 * ESMTP server. Don't try to ship the message,
959 * and suppress deletion so it can be retried on
960 * a future retrieval cycle.
962 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
964 return(PS_TRANSIENT);
966 case 552: /* message exceeds fixed maximum message size */
968 * Permanent no-go condition on the
969 * ESMTP server. Don't try to ship the message,
970 * and allow it to be deleted.
972 SMTP_rset(ctl->smtp_socket); /* required by RFC1870 */
976 default: /* retry with invoking user's address */
977 if (SMTP_from(ctl->smtp_socket, user, options) != SM_OK)
979 error(0, -1, "SMTP error: %s", smtp_response);
981 return(PS_SMTP); /* should never happen */
987 * Now list the recipient addressees
989 * RFC 1123 requires that the domain name part of the
990 * RCPT TO address be "canonicalized", that is a FQDN
991 * or MX but not a CNAME. Some listeners (like exim)
994 for (idp = xmit_names; idp; idp = idp->next)
995 if (idp->val.num == XMIT_ACCEPT)
998 snprintf(addr, sizeof(addr)-1, "%s@%s", idp->id,ctl->smtphost);
1000 sprintf(addr, "%s@%s", idp->id, ctl->smtphost);
1001 #endif /* HAVE_SNPRINTF */
1003 if (SMTP_rcpt(ctl->smtp_socket, addr) == SM_OK)
1008 idp->val.num = XMIT_ANTISPAM;
1010 "SMTP listener doesn't like recipient address `%s'", idp->id);
1013 if (!good_addresses)
1015 #ifdef HAVE_SNPRINTF
1016 snprintf(addr, sizeof(addr)-1, "%s@%s", idp->id, ctl->smtphost);
1018 sprintf(addr, "%s@%s", idp->id, ctl->smtphost);
1019 #endif /* HAVE_SNPRINTF */
1021 if (SMTP_rcpt(ctl->smtp_socket, user) != SM_OK)
1023 error(0, 0, "can't even send to calling user!");
1029 /* tell it we're ready to send data */
1030 SMTP_data(ctl->smtp_socket);
1033 /* we may need to strip carriage returns */
1038 for (sp = tp = headers; *sp; sp++)
1045 /* write all the headers */
1047 if (ctl->mda && sinkfp)
1048 n = fwrite(headers, 1, strlen(headers), sinkfp);
1049 else if (ctl->smtp_socket != -1)
1050 n = SockWrite(ctl->smtp_socket, headers, strlen(headers));
1055 error(0, errno, "writing RFC822 headers");
1059 signal(SIGCHLD, sigchld);
1063 else if (outlevel == O_VERBOSE)
1066 /* write error notifications */
1067 #ifdef HAVE_RES_SEARCH
1068 if (no_local_matches || has_nuls || bad_addresses)
1070 if (has_nuls || bad_addresses)
1071 #endif /* HAVE_RES_SEARCH */
1074 char errhd[USERNAMELEN + POPBUFSIZE], *errmsg;
1077 (void) strcpy(errhd, "X-Fetchmail-Warning: ");
1078 #ifdef HAVE_RES_SEARCH
1079 if (no_local_matches)
1081 if (reject_count != 1)
1082 strcat(errhd, "no recipient addresses matched declared local names");
1085 for (idp = xmit_names; idp; idp = idp->next)
1086 if (idp->val.num == XMIT_REJECT)
1088 sprintf(errhd+strlen(errhd), "recipient address %s didn't match any local name", idp->id);
1091 #endif /* HAVE_RES_SEARCH */
1095 if (errhd[sizeof("X-Fetchmail-Warning: ")])
1096 strcat(errhd, "; ");
1097 strcat(errhd, "message has embedded NULs");
1102 if (errhd[sizeof("X-Fetchmail-Warning: ")])
1103 strcat(errhd, "; ");
1104 strcat(errhd, "SMTP listener rejected local recipient addresses: ");
1105 errlen = strlen(errhd);
1106 for (idp = xmit_names; idp; idp = idp->next)
1107 if (idp->val.num == XMIT_ANTISPAM)
1108 errlen += strlen(idp->id) + 2;
1110 errmsg = alloca(errlen+3);
1111 (void) strcpy(errmsg, errhd);
1112 for (idp = xmit_names; idp; idp = idp->next)
1113 if (idp->val.num == XMIT_ANTISPAM)
1115 strcat(errmsg, idp->id);
1117 strcat(errmsg, ", ");
1122 /* ship out the error line */
1124 stuffline(ctl, errmsg, protocol->delimited);
1127 free_str_list(&xmit_names);
1129 /* issue the delimiter line */
1134 stuffline(ctl, buf, protocol->delimited);
1139 static int readbody(sock, ctl, forward, len, delimited)
1140 /* read and dispose of a message body presented on sock */
1141 struct query *ctl; /* query control record */
1142 int sock; /* to which the server is connected */
1143 int len; /* length of message */
1144 flag forward; /* TRUE to forward */
1145 flag delimited; /* does the protocol use a message delimiter? */
1148 char buf[MSGBUFSIZE+1], *cp;
1150 /* pass through the text lines */
1151 while (delimited || len > 0)
1153 if ((linelen = SockRead(sock, buf, sizeof(buf)-1)) == -1)
1158 signal(SIGCHLD, sigchld);
1162 set_timeout(ctl->server.timeout);
1164 /* write the message size dots */
1167 sizeticker += linelen;
1168 while (sizeticker >= SIZETICKER)
1170 if (outlevel > O_SILENT)
1172 sizeticker -= SIZETICKER;
1177 /* check for end of message */
1178 if (delimited && *buf == '.')
1179 if (buf[1] == '\r' && buf[2] == '\n' && buf[3] == '\0')
1181 else if (buf[1] == '\n' && buf[2] == '\0')
1184 /* ship out the text line */
1187 int n = stuffline(ctl, buf, delimited);
1191 error(0, errno, "writing message text");
1195 signal(SIGCHLD, sigchld);
1199 else if (outlevel == O_VERBOSE)
1209 kerberos_auth (socket, canonical)
1210 /* authenticate to the server host using Kerberos V4 */
1211 int socket; /* socket to server host */
1213 char *canonical; /* server name */
1215 const char *canonical; /* server name */
1218 char * host_primary;
1222 Key_schedule schedule;
1225 ticket = ((KTEXT) (malloc (sizeof (KTEXT_ST))));
1226 rem = (krb_sendauth (0L, socket, ticket, "pop",
1228 ((char *) (krb_realmofhost (canonical))),
1229 ((unsigned long) 0),
1233 ((struct sockaddr_in *) 0),
1234 ((struct sockaddr_in *) 0),
1237 if (rem != KSUCCESS)
1239 error(0, -1, "kerberos error %s", (krb_get_err_text (rem)));
1244 #endif /* KERBEROS_V4 */
1246 int do_protocol(ctl, proto)
1247 /* retrieve messages from server using given protocol method table */
1248 struct query *ctl; /* parsed options with merged-in defaults */
1249 const struct method *proto; /* protocol method table */
1251 int ok, js, pst, sock = -1;
1252 char *msg, *cp, realname[HOSTLEN];
1256 if (ctl->server.preauthenticate == A_KERBEROS_V4)
1258 error(0, -1, "Kerberos V4 support not linked.");
1261 #endif /* KERBEROS_V4 */
1263 /* lacking methods, there are some options that may fail */
1266 /* check for unsupported options */
1269 "Option --flush is not supported with %s",
1273 else if (ctl->fetchall) {
1275 "Option --all is not supported with %s",
1280 if (!proto->getsizes && ctl->limit)
1283 "Option --limit is not supported with %s",
1290 tag[0] = '\0'; /* nuke any tag hanging out from previous query */
1292 error_init(poll_interval == 0 && !logfile);
1294 /* set up the server-nonresponse timeout */
1295 sigsave = signal(SIGALRM, timeout_handler);
1296 set_timeout(mytimeout = ctl->server.timeout);
1298 if ((js = setjmp(restart)) == 1)
1301 "timeout after %d seconds waiting for %s.",
1302 ctl->server.timeout, ctl->server.pollname);
1303 if (ctl->smtp_socket != -1)
1304 close(ctl->smtp_socket);
1311 char buf [POPBUFSIZE+1], *sp, *realhost;
1312 int *msgsizes, len, num, count, new, deletions = 0;
1316 /* execute pre-initialization command, if any */
1317 if (ctl->preconnect && (ok = system(ctl->preconnect)))
1319 sprintf(buf, "pre-connection command failed with status %d", ok);
1325 /* open a socket to the mail server */
1326 port = ctl->server.port ? ctl->server.port : protocol->port;
1327 realhost = ctl->server.via ? ctl->server.via : ctl->server.pollname;
1328 if ((sock = SockOpen(realhost, port)) == -1)
1330 #ifndef EHOSTUNREACH
1331 #define EHOSTUNREACH (-1)
1333 if (outlevel == O_VERBOSE || errno != EHOSTUNREACH)
1335 error_build("fetchmail: %s connection to %s failed: ",
1336 protocol->name, ctl->server.pollname);
1337 if (h_errno == HOST_NOT_FOUND)
1338 error_complete(0, 0, "host is unknown");
1339 else if (h_errno == NO_ADDRESS)
1340 error_complete(0, 0, "name is valid but has no IP address");
1341 else if (h_errno == NO_RECOVERY)
1342 error_complete(0, 0, "unrecoverable name server error");
1343 else if (h_errno == TRY_AGAIN)
1344 error_complete(0, 0, "temporary name server error");
1346 error_complete(0, 0, "unknown DNS error %d", h_errno);
1348 error_complete(0, errno, "local error");
1355 if (ctl->server.preauthenticate == A_KERBEROS_V4)
1357 ok = kerberos_auth(sock, ctl->server.truename);
1360 set_timeout(ctl->server.timeout);
1362 #endif /* KERBEROS_V4 */
1364 /* accept greeting message from mail server */
1365 ok = (protocol->parse_response)(sock, buf);
1368 set_timeout(ctl->server.timeout);
1371 * Try to parse the host's actual name out of the greeting
1372 * message. We do this so that the progress messages will
1373 * make sense even if the connection is indirected through
1374 * ssh. *Do* use this for hacking reply headers, but *don't*
1375 * use it for error logging, as the names in the log should
1376 * correlate directly back to rc file entries.
1378 * This assumes that the first space-delimited token found
1379 * that contains at least two dots (with the characters on
1380 * each side of the dot alphanumeric to exclude version
1381 * numbers) is the hostname. The hostname candidate may not
1382 * contain @ -- if it does it's probably a mailserver
1383 * maintainer's name. If no such token is found, fall back on
1384 * the .fetchmailrc id.
1387 sp = (char *)NULL; /* sacrifice to -Wall */
1388 for (cp = buf; *cp; cp++)
1392 case 0: /* skip to end of current token */
1397 case 1: /* look for blank-delimited token */
1405 case 2: /* look for first dot */
1408 else if (*cp == ' ')
1410 else if (*cp == '.' && isalpha(cp[1]) && isalpha(cp[-1]))
1414 case 3: /* look for second dot */
1417 else if (*cp == ' ')
1419 else if (*cp == '.' && isalpha(cp[1]) && isalpha(cp[-1]))
1423 case 4: /* look for trailing space */
1426 else if (*cp == ' ')
1437 char *tp = realname;
1444 strcpy(realname, ctl->server.pollname);
1446 /* try to get authorized to fetch mail */
1447 if (protocol->getauth)
1449 shroud = ctl->password;
1450 ok = (protocol->getauth)(sock, ctl, buf);
1451 shroud = (char *)NULL;
1454 if (ok == PS_LOCKBUSY)
1455 error(0, -1, "Lock-busy error on %s@%s",
1462 error(0, -1, "Authorization failure on %s@%s",
1468 set_timeout(ctl->server.timeout);
1471 ctl->errcount = fetches = 0;
1473 /* now iterate over each folder selected */
1474 for (idp = ctl->mailboxes; idp; idp = idp->next)
1476 if (outlevel >= O_VERBOSE)
1478 error(0, 0, "selecting folder %s");
1480 error(0, 0, "selecting default folder");
1482 /* compute number of messages and number of new messages waiting */
1483 ok = (protocol->getrange)(sock, ctl, idp->id, &count, &new);
1486 set_timeout(ctl->server.timeout);
1488 /* show user how many messages we downloaded */
1490 (void) sprintf(buf, "%s@%s:%s",
1491 ctl->remotename, realname, idp->id);
1493 (void) sprintf(buf, "%s@%s", ctl->remotename, realname);
1494 if (outlevel > O_SILENT)
1495 if (count == -1) /* only used for ETRN */
1496 error(0, 0, "Polling %s", buf);
1497 else if (count == 0)
1499 /* these are pointless in normal daemon mode */
1500 if (poll_interval == 0 || outlevel == O_VERBOSE )
1501 error(0, 0, "No mail at %s", buf);
1505 if (new != -1 && (count - new) > 0)
1506 error(0, 0, "%d message%s (%d seen) at %s.",
1507 count, count > 1 ? "s" : "", count-new, buf);
1509 error(0, 0, "%d message%s at %s.",
1510 count, count > 1 ? "s" : "", buf);
1515 if (new == -1 || ctl->fetchall)
1517 ok = ((new > 0) ? PS_SUCCESS : PS_NOMAIL);
1522 flag force_retrieval;
1525 * What forces this code is that in POP3 and IMAP2BIS you can't
1526 * fetch a message without having it marked `seen'. In IMAP4,
1527 * on the other hand, you can (peek_capable is set to convey
1530 * The result of being unable to peek is that if there's
1531 * any kind of transient error (DNS lookup failure, or
1532 * sendmail refusing delivery due to process-table limits)
1533 * the message will be marked "seen" on the server without
1534 * having been delivered. This is not a big problem if
1535 * fetchmail is running in foreground, because the user
1536 * will see a "skipped" message when it next runs and get
1539 * But in daemon mode this leads to the message being silently
1540 * ignored forever. This is not acceptable.
1542 * We compensate for this by checking the error count from the
1543 * previous pass and forcing all messages to be considered new
1546 force_retrieval = !peek_capable && (ctl->errcount > 0);
1549 * We may need to get sizes in order to check message
1550 * limits. Or it may be forced because the fetch methods
1551 * don't return reliable sizes.
1553 msgsizes = (int *)NULL;
1554 if (proto->getsizes && (proto->force_getsizes || ctl->limit > 0))
1556 msgsizes = (int *)alloca(sizeof(int) * count);
1558 ok = (proto->getsizes)(sock, count, msgsizes);
1561 set_timeout(ctl->server.timeout);
1564 /* read, forward, and delete messages */
1565 for (num = 1; num <= count; num++)
1567 flag toolarge = (ctl->limit > 0)
1568 && msgsizes && (msgsizes[num-1] > ctl->limit);
1569 flag fetch_it = !toolarge
1570 && (ctl->fetchall || force_retrieval || !(protocol->is_old && (protocol->is_old)(sock,ctl,num)));
1571 flag suppress_delete = FALSE;
1572 flag suppress_forward = FALSE;
1573 flag retained = FALSE;
1575 /* we may want to reject this message if it's old */
1578 if (outlevel > O_SILENT)
1580 error_build("skipping message %d", num);
1582 error_build(" (oversized, %d bytes)", msgsizes[num-1]);
1587 flag wholesize = !protocol->fetch_body;
1589 /* request a message */
1590 ok = (protocol->fetch_headers)(sock, ctl, num, &len);
1593 set_timeout(ctl->server.timeout);
1595 /* -1 means we didn't see a size in the response */
1596 if (len == -1 && msgsizes)
1598 len = msgsizes[num - 1];
1602 if (outlevel > O_SILENT)
1604 error_build("reading message %d of %d",num,count);
1607 error_build(" (%d %sbytes)",
1608 len, wholesize ? "" : "header ");
1609 if (outlevel == O_VERBOSE)
1610 error_complete(0, 0, "");
1616 * Read the message headers and ship them to the
1619 ok = readheaders(sock, len, ctl, realname, num);
1620 if (ok == PS_RETAINED)
1621 suppress_forward = retained = TRUE;
1622 else if (ok == PS_TRANSIENT)
1623 suppress_delete = suppress_forward = TRUE;
1624 else if (ok == PS_REFUSED)
1625 suppress_forward = TRUE;
1628 set_timeout(ctl->server.timeout);
1631 * If we're using IMAP4 or something else that
1632 * can fetch headers separately from bodies,
1633 * it's time to request the body now. This
1634 * fetch may be skipped if we got an anti-spam
1635 * or other PS_REFUSED error response during
1638 if (protocol->fetch_body)
1640 if ((ok = (protocol->trail)(sock, ctl, num)))
1642 set_timeout(ctl->server.timeout);
1644 if (!suppress_forward)
1646 if ((ok=(protocol->fetch_body)(sock,ctl,num,&len)))
1648 if (outlevel > O_SILENT && !msgsizes)
1649 error_build(" (%d body bytes) ", len);
1650 set_timeout(ctl->server.timeout);
1654 /* process the body now */
1661 protocol->delimited);
1662 if (ok == PS_TRANSIENT)
1663 suppress_delete = suppress_forward = TRUE;
1666 set_timeout(ctl->server.timeout);
1668 /* tell server we got it OK and resynchronize */
1669 if (protocol->trail)
1671 ok = (protocol->trail)(sock, ctl, num);
1674 set_timeout(ctl->server.timeout);
1678 /* end-of-message processing starts here */
1679 if (outlevel == O_VERBOSE)
1680 fputc('\n', stderr);
1686 /* close the delivery pipe, we'll reopen before next message */
1687 rc = pclose(sinkfp);
1688 signal(SIGCHLD, sigchld);
1691 error(0, -1, "MDA exited abnormally or returned nonzero status");
1695 else if (!suppress_forward)
1697 /* write message terminator */
1698 if (SMTP_eom(ctl->smtp_socket) != SM_OK)
1700 error(0, -1, "SMTP listener refused delivery");
1702 suppress_delete = TRUE;
1710 * At this point in flow of control, either we've bombed
1711 * on a protocol error or had delivery refused by the SMTP
1712 * server (unlikely -- I've never seen it) or we've seen
1713 * `accepted for delivery' and the message is shipped.
1714 * It's safe to mark the message seen and delete it on the
1718 /* maybe we delete this message now? */
1721 if (outlevel > O_SILENT)
1722 error_complete(0, 0, " retained");
1724 else if (protocol->delete
1726 && (fetch_it ? !ctl->keep : ctl->flush))
1729 if (outlevel > O_SILENT)
1730 error_complete(0, 0, " flushed");
1731 ok = (protocol->delete)(sock, ctl, num);
1734 set_timeout(ctl->server.timeout);
1735 delete_str(&ctl->newsaved, num);
1737 else if (outlevel > O_SILENT)
1738 error_complete(0, 0, " not flushed");
1740 /* perhaps this as many as we're ready to handle */
1741 if (ctl->fetchlimit > 0 && ctl->fetchlimit <= fetches)
1748 set_timeout(ctl->server.timeout);
1749 ok = gen_transact(sock, protocol->exit_cmd);
1751 ok = (fetches > 0) ? PS_SUCCESS : PS_NOMAIL;
1757 set_timeout(ctl->server.timeout);
1758 if (ok != 0 && ok != PS_SOCKET)
1759 gen_transact(sock, protocol->exit_cmd);
1764 msg = (char *)NULL; /* sacrifice to -Wall */
1771 msg = "authorization";
1774 msg = "missing or bad RFC822 header";
1780 msg = "client/server synchronization";
1783 msg = "client/server protocol";
1786 msg = "lock busy on server";
1789 msg = "SMTP transaction";
1792 error(0, 0, "undefined");
1795 if (ok==PS_SOCKET || ok==PS_AUTHFAIL || ok==PS_SYNTAX
1796 || ok==PS_IOERR || ok==PS_ERROR || ok==PS_PROTOCOL
1797 || ok==PS_LOCKBUSY || ok==PS_SMTP)
1798 error(0,-1, "%s error while fetching from %s", msg, ctl->server.pollname);
1801 /* execute post-initialization command, if any */
1802 if (ctl->postconnect && (ok = system(ctl->postconnect)))
1806 sprintf(buf, "post-connection command failed with status %d", ok);
1808 if (ok == PS_SUCCESS)
1812 signal(SIGALRM, sigsave);
1816 #if defined(HAVE_STDARG_H)
1817 void gen_send(int sock, char *fmt, ... )
1818 /* assemble command in printf(3) style and send to the server */
1820 void gen_send(sock, fmt, va_alist)
1821 /* assemble command in printf(3) style and send to the server */
1822 int sock; /* socket to which server is connected */
1823 const char *fmt; /* printf-style format */
1827 char buf [POPBUFSIZE+1];
1830 if (protocol->tagged)
1831 (void) sprintf(buf, "%s ", GENSYM);
1835 #if defined(HAVE_STDARG_H)
1840 #ifdef HAVE_VSNPRINTF
1841 vsnprintf(buf + strlen(buf), sizeof(buf), fmt, ap);
1843 vsprintf(buf + strlen(buf), fmt, ap);
1847 strcat(buf, "\r\n");
1848 SockWrite(sock, buf, strlen(buf));
1850 if (outlevel == O_VERBOSE)
1854 if (shroud && shroud[0] && (cp = strstr(buf, shroud)))
1858 sp = cp + strlen(shroud);
1864 buf[strlen(buf)-2] = '\0';
1865 error(0, 0, "%s> %s", protocol->name, buf);
1869 int gen_recv(sock, buf, size)
1870 /* get one line of input from the server */
1871 int sock; /* socket to which server is connected */
1872 char *buf; /* buffer to receive input */
1873 int size; /* length of buffer */
1875 if (SockRead(sock, buf, size) == -1)
1879 if (buf[strlen(buf)-1] == '\n')
1880 buf[strlen(buf)-1] = '\0';
1881 if (buf[strlen(buf)-1] == '\r')
1882 buf[strlen(buf)-1] = '\r';
1883 if (outlevel == O_VERBOSE)
1884 error(0, 0, "%s< %s", protocol->name, buf);
1889 #if defined(HAVE_STDARG_H)
1890 int gen_transact(int sock, char *fmt, ... )
1891 /* assemble command in printf(3) style, send to server, accept a response */
1893 int gen_transact(int sock, fmt, va_alist)
1894 /* assemble command in printf(3) style, send to server, accept a response */
1895 int sock; /* socket to which server is connected */
1896 const char *fmt; /* printf-style format */
1901 char buf [POPBUFSIZE+1];
1904 if (protocol->tagged)
1905 (void) sprintf(buf, "%s ", GENSYM);
1909 #if defined(HAVE_STDARG_H)
1914 #ifdef HAVE_VSNPRINTF
1915 vsnprintf(buf + strlen(buf), sizeof(buf), fmt, ap);
1917 vsprintf(buf + strlen(buf), fmt, ap);
1921 strcat(buf, "\r\n");
1922 SockWrite(sock, buf, strlen(buf));
1924 if (outlevel == O_VERBOSE)
1928 if (shroud && shroud[0] && (cp = strstr(buf, shroud)))
1932 sp = cp + strlen(shroud);
1938 buf[strlen(buf)-1] = '\0';
1939 error(0, 0, "%s> %s", protocol->name, buf);
1942 /* we presume this does its own response echoing */
1943 ok = (protocol->parse_response)(sock, buf);
1944 set_timeout(mytimeout);
1949 /* driver.c ends here */