2 * driver.c -- generic driver for mail fetch method protocols
4 * Copyright 1996 by Eric S. Raymond
6 * For license terms, see the file COPYING in this directory.
15 #if defined(STDC_HEADERS)
18 #if defined(HAVE_UNISTD_H)
21 #if defined(HAVE_STDARG_H)
26 #if defined(HAVE_ALLOCA_H)
32 #ifdef HAVE_GETHOSTBYNAME
35 #endif /* HAVE_GETHOSTBYNAME */
40 #include <netinet/in.h>
42 #endif /* KERBEROS_V4 */
44 #include "fetchmail.h"
48 /* BSD portability hack...I know, this is an ugly place to put it */
49 #if !defined(SIGCHLD) && defined(SIGCLD)
50 #define SIGCHLD SIGCLD
53 #define SMTP_PORT 25 /* standard SMTP service port */
55 extern char *strstr(); /* needed on sysV68 R3V7.1. */
57 int batchlimit; /* how often to tear down the delivery connection */
58 int fetchlimit; /* how often to tear down the server connection */
59 int batchcount; /* count of messages sent in current batch */
60 int peek_capable; /* can we peek for better error recovery? */
62 static const struct method *protocol;
63 static jmp_buf restart;
67 #define GENSYM (sprintf(tag, "a%04d", ++tagnum), tag)
69 static char *shroud; /* string to shroud in debug output, if non-NULL */
70 static int mytimeout; /* value of nonreponse timeout */
72 static void vtalarm(int timeleft)
73 /* reset the nonresponse-timeout */
75 struct itimerval ntimeout;
77 ntimeout.it_interval.tv_sec = ntimeout.it_interval.tv_usec = 0;
78 ntimeout.it_value.tv_sec = timeleft;
79 ntimeout.it_value.tv_usec = 0;
80 setitimer(ITIMER_VIRTUAL, &ntimeout, (struct itimerval *)NULL);
83 static void vtalarm_handler (int signal)
84 /* handle server-timeout SIGVTALARM signal */
89 #ifdef HAVE_RES_SEARCH
92 static int is_host_alias(const char *name, struct query *ctl)
93 /* determine whether name is a DNS alias of the hostname */
96 struct mxentry *mxp, *mxrecords;
99 * The first two checks are optimizations that will catch a good
100 * many cases. (1) check against the hostname the user
101 * specified. Odds are good this will either be the mailserver's
102 * FQDN or a suffix of it with the mailserver's domain's default
103 * host name omitted. Then check the rest of the `also known as'
104 * cache accumulated by previous DNS checks. This cache is primed
105 * by the aka list option.
107 * (2) check against the mailserver's FQDN, in case
108 * it's not the same as the declared hostname.
110 * Either of these on a mail address is definitive. Only if the
111 * name doesn't match either is it time to call the bind library.
112 * If this happens odds are good we're looking at an MX name.
114 if (str_in_list(&ctl->server.lead_server->names, name))
116 else if (strcmp(name, ctl->server.canonical_name) == 0)
118 else if (!ctl->server.dns)
122 * We know DNS service was up at the beginning of this poll cycle.
123 * If it's down, our nameserver has crashed. We don't want to try
124 * delivering the current message or anything else from this
125 * mailbox until it's back up.
127 else if ((he = gethostbyname(name)) != (struct hostent *)NULL)
129 if (strcmp(ctl->server.canonical_name, he->h_name) == 0)
137 case HOST_NOT_FOUND: /* specified host is unknown */
138 case NO_ADDRESS: /* valid, but does not have an IP address */
141 case NO_RECOVERY: /* non-recoverable name server error */
142 case TRY_AGAIN: /* temporary error on authoritative server */
144 if (outlevel != O_SILENT)
145 putchar('\n'); /* terminate the progress message */
147 "nameserver failure while looking for `%s' during poll of %s.",
148 name, ctl->server.names->id);
150 longjmp(restart, 2); /* try again next poll cycle */
155 * We're only here if DNS was OK but the gethostbyname() failed
156 * with a HOST_NOT_FOUND or NO_ADDRESS error.
157 * Search for a name match on MX records pointing to the server.
160 if ((mxrecords = getmxrecords(name)) == (struct mxentry *)NULL)
164 case HOST_NOT_FOUND: /* specified host is unknown */
165 case NO_ADDRESS: /* valid, but does not have an IP address */
169 case NO_RECOVERY: /* non-recoverable name server error */
170 case TRY_AGAIN: /* temporary error on authoritative server */
173 "nameserver failure while looking for `%s' during poll of %s.",
174 name, ctl->server.names->id);
176 longjmp(restart, 2); /* try again next poll cycle */
182 for (mxp = mxrecords; mxp->name; mxp++)
183 if (strcmp(ctl->server.canonical_name, mxp->name) == 0)
189 /* add this name to relevant server's `also known as' list */
190 save_str(&ctl->server.lead_server->names, -1, name);
194 static void map_name(name, ctl, xmit_names)
195 /* add given name to xmit_names if it matches declared localnames */
196 const char *name; /* name to map */
197 struct query *ctl; /* list of permissible aliases */
198 struct idlist **xmit_names; /* list of recipient names parsed out */
202 lname = idpair_find(&ctl->localnames, name);
203 if (!lname && ctl->wildcard)
206 if (lname != (char *)NULL)
208 if (outlevel == O_VERBOSE)
209 error(0, 0, "mapped %s to local %s", name, lname);
210 save_str(xmit_names, -1, lname);
214 void find_server_names(hdr, ctl, xmit_names)
215 /* parse names out of a RFC822 header into an ID list */
216 const char *hdr; /* RFC822 header in question */
217 struct query *ctl; /* list of permissible aliases */
218 struct idlist **xmit_names; /* list of recipient names parsed out */
220 if (hdr == (char *)NULL)
226 if ((cp = nxtaddr(hdr)) != (char *)NULL)
230 if ((atsign = strchr(cp, '@')))
235 * Does a trailing segment of the hostname match something
236 * on the localdomains list? If so, save the whole name
239 for (idp = ctl->server.localdomains; idp; idp = idp->next)
243 rhs = atsign + 1 + (strlen(atsign) - strlen(idp->id));
244 if ((rhs[-1] == '.' || rhs[-1] == '@')
245 && strcmp(rhs, idp->id) == 0)
247 if (outlevel == O_VERBOSE)
248 error(0, 0, "passed through %s matching %s",
250 save_str(xmit_names, -1, cp);
256 * Check to see if the right-hand part is an alias
257 * or MX equivalent of the mailserver. If it's
258 * not, skip this name. If it is, we'll keep
259 * going and try to find a mapping to a client name.
261 if (!is_host_alias(atsign+1, ctl))
266 map_name(cp, ctl, xmit_names);
268 ((cp = nxtaddr((char *)NULL)) != (char *)NULL);
272 char *parse_received(struct query *ctl, char *bufp)
276 static char rbuf[HOSTLEN + USERNAMELEN + 4];
279 * Try to extract the real envelope addressee. We look here
280 * specifically for the mailserver's Received line.
281 * Note: this will only work for sendmail, or an MTA that
282 * shares sendmail's convention for embedding the envelope
283 * address in the Received line. Sendmail itself only
284 * does this when the mail has a single recipient.
286 if ((ok = strstr(bufp, "by ")) == (char *)NULL)
292 /* extract space-delimited token after "by " */
293 for (sp = ok + 3; isspace(*sp); sp++)
296 for (; !isspace(*sp); sp++)
301 * If it's a DNS name of the mail server, look for the
302 * recipient name after a following "for". Otherwise
305 if (is_host_alias(rbuf, ctl))
306 ok = strstr(sp, "for ");
319 while (*sp && *sp != '>' && *sp != '@' && *sp != ';')
324 /* uh oh -- whitespace here can't be right! */
335 if (outlevel == O_VERBOSE)
336 error(0, 0, "found Received address `%s'", rbuf);
340 #endif /* HAVE_RES_SEARCH */
342 static FILE *smtp_open(struct query *ctl)
343 /* try to open a socket to the appropriate SMTP server for this query */
347 lead = ctl->lead_smtp; /* go to the SMTP leader for this query */
349 /* maybe it's time to close the socket in order to force delivery */
350 if (batchlimit && lead->smtp_sockfp && batchcount++ == batchlimit)
352 fclose(lead->smtp_sockfp);
353 lead->smtp_sockfp = (FILE *)NULL;
358 * RFC 1123 requires that the domain name in HELO address is a
359 * "valid principal domain name" for the client host. We
360 * violate this with malice aforethought in order to make the
361 * Received headers and logging look right.
363 * In fact this code relies on the RFC1123 requirement that the
364 * SMTP listener must accept messages even if verification of the
365 * HELO name fails (RFC1123 section 5.2.5, paragraph 2).
368 /* if no socket to this host is already set up, try to open ESMTP */
369 if (lead->smtp_sockfp == (FILE *)NULL)
371 if ((lead->smtp_sockfp = SockOpen(lead->smtphost, SMTP_PORT)) == (FILE *)NULL)
372 return((FILE *)NULL);
373 else if (SMTP_ok(lead->smtp_sockfp) != SM_OK
374 || SMTP_ehlo(lead->smtp_sockfp,
375 ctl->server.names->id,
376 &lead->server.esmtp_options) != SM_OK)
379 * RFC 1869 warns that some listeners hang up on a failed EHLO,
380 * so it's safest not to assume the socket will still be good.
382 fclose(lead->smtp_sockfp);
383 lead->smtp_sockfp = (FILE *)NULL;
387 /* if opening for ESMTP failed, try SMTP */
388 if (lead->smtp_sockfp == (FILE *)NULL)
390 if ((lead->smtp_sockfp = SockOpen(lead->smtphost, SMTP_PORT)) == (FILE *)NULL)
391 return((FILE *)NULL);
392 else if (SMTP_ok(lead->smtp_sockfp) != SM_OK
393 || SMTP_helo(lead->smtp_sockfp, ctl->server.names->id) != SM_OK)
395 fclose(lead->smtp_sockfp);
396 lead->smtp_sockfp = (FILE *)NULL;
400 return(lead->smtp_sockfp);
403 static int gen_readmsg(sockfp, len, delimited, ctl, realname)
404 /* read message content and ship to SMTP or MDA */
405 FILE *sockfp; /* to which the server is connected */
406 long len; /* length of message */
407 int delimited; /* does the protocol use a message delimiter? */
408 struct query *ctl; /* query control record */
409 char *realname; /* real name of host */
411 char buf [MSGBUFSIZE+1];
412 int from_offs, to_offs, cc_offs, bcc_offs, ctt_offs, env_offs, rtp_offs;
413 char *headers, *received_for;
414 int n, oldlen, ch, sizeticker, delete_ok, remaining;
416 RETSIGTYPE (*sigchld)();
417 #ifdef HAVE_GETHOSTBYNAME
418 char rbuf[HOSTLEN + USERNAMELEN + 4];
419 #endif /* HAVE_GETHOSTBYNAME */
421 struct idlist *idp, *xmit_names;
422 int good_addresses, bad_addresses;
423 #ifdef HAVE_RES_SEARCH
424 int no_local_matches = FALSE;
425 #endif /* HAVE_RES_SEARCH */
431 /* read message headers */
432 headers = received_for = NULL;
433 from_offs = to_offs = cc_offs = bcc_offs = ctt_offs = env_offs = rtp_offs = -1;
439 line = xmalloc(sizeof(buf));
442 if (!SockGets(buf, sizeof(buf)-1, sockfp))
444 vtalarm(ctl->server.timeout);
445 /* leave extra room for reply_hack to play with */
446 line = realloc(line, strlen(line) + strlen(buf) + HOSTLEN + 1);
448 if (line[0] == '\r' && line[1] == '\n')
451 /* we may need to grab RFC822 continuations */
452 ((ch = SockPeek(sockfp)) == ' ' || ch == '\t');
454 /* write the message size dots */
456 if ((outlevel > O_SILENT && outlevel < O_VERBOSE) && n > 0)
459 while (sizeticker >= SIZETICKER)
462 sizeticker -= SIZETICKER;
467 /* check for end of headers; don't save terminating line */
468 if (line[0] == '\r' && line[1] == '\n')
475 reply_hack(line, realname);
479 oldlen = strlen(line);
480 headers = xmalloc(oldlen + 1);
481 (void) strcpy(headers, line);
489 newlen = oldlen + strlen(line);
490 headers = realloc(headers, newlen + 1);
493 strcpy(headers + oldlen, line);
495 line = headers + oldlen;
499 if (from_offs == -1 && !strncasecmp("From:", line, 5))
500 from_offs = (line - headers);
501 else if (from_offs == -1 && !strncasecmp("Resent-From:", line, 12))
502 from_offs = (line - headers);
503 else if (from_offs == -1 && !strncasecmp("Apparently-From:", line, 16))
504 from_offs = (line - headers);
506 else if (rtp_offs == -1 && !strncasecmp("Return-Path:", line, 12))
507 rtp_offs = (line - headers);
509 else if (!strncasecmp("To:", line, 3))
510 to_offs = (line - headers);
512 else if (ctl->server.envelope != STRING_DISABLED && env_offs == -1
513 && !strncasecmp(ctl->server.envelope,
515 strlen(ctl->server.envelope)))
516 env_offs = (line - headers);
518 else if (!strncasecmp("Cc:", line, 3))
519 cc_offs = (line - headers);
521 else if (!strncasecmp("Bcc:", line, 4))
522 bcc_offs = (line - headers);
524 else if (!strncasecmp("Content-Transfer-Encoding:", line, 26))
525 ctt_offs = (line - headers);
527 #ifdef HAVE_RES_SEARCH
528 else if (ctl->server.envelope != STRING_DISABLED && MULTIDROP(ctl) && !received_for && !strncasecmp("Received:", line, 9))
529 received_for = parse_received(ctl, line);
530 #endif /* HAVE_RES_SEARCH */
534 * Hack time. If the first line of the message was blank, with no headers
535 * (this happens occasionally due to bad gatewaying software) cons up
536 * a set of fake headers.
538 * If you modify the fake header template below, be sure you don't
539 * make either From or To address @-less, otherwise the reply_hack
540 * logic will do bad things.
542 if (headers == (char *)NULL)
545 "From: <FETCHMAIL-DAEMON@%s>\r\nTo: %s@localhost\r\nSubject: Headerless mail from %s's mailbox on %s\r\n",
546 fetchmailhost, user, ctl->remotename, realname);
547 headers = xstrdup(buf);
551 * We can now process message headers before reading the text.
552 * In fact we have to, as this will tell us where to forward to.
555 /* cons up a list of local recipients */
556 xmit_names = (struct idlist *)NULL;
557 bad_addresses = good_addresses = 0;
558 #ifdef HAVE_RES_SEARCH
559 /* is this a multidrop box? */
562 if (env_offs > -1) /* We have the actual envelope addressee */
563 find_server_names(headers + env_offs, ctl, &xmit_names);
564 else if (received_for)
566 * We have the Received for addressee.
567 * It has to be a mailserver address, or we
568 * wouldn't have got here.
570 map_name(received_for, ctl, &xmit_names);
574 * We haven't extracted the envelope address.
575 * So check all the header addresses.
578 find_server_names(headers + to_offs, ctl, &xmit_names);
580 find_server_names(headers + cc_offs, ctl, &xmit_names);
582 find_server_names(headers + bcc_offs, ctl, &xmit_names);
586 no_local_matches = TRUE;
587 save_str(&xmit_names, -1, user);
588 if (outlevel == O_VERBOSE)
590 "no local matches, forwarding to %s",
594 else /* it's a single-drop box, use first localname */
595 #endif /* HAVE_RES_SEARCH */
596 save_str(&xmit_names, -1, ctl->localnames->id);
598 /* time to address the message */
599 if (ctl->mda) /* we have a declared MDA */
605 * We go through this in order to be able to handle very
606 * long lists of users and (re)implement %s.
608 for (idp = xmit_names; idp; idp = idp->next)
609 length += (strlen(idp->id) + 1);
610 names = (char *)alloca(length);
612 for (idp = xmit_names; idp; idp = idp->next)
614 strcat(names, idp->id);
617 cmd = (char *)alloca(strlen(ctl->mda) + length);
618 sprintf(cmd, ctl->mda, names);
619 if (outlevel == O_VERBOSE)
620 error(0, 0, "about to deliver with: %s", cmd);
624 * Arrange to run with user's permissions if we're root.
625 * This will initialize the ownership of any files the
626 * MDA creates properly. (The seteuid call is available
627 * under all BSDs and Linux)
630 #endif /* HAVE_SETEUID */
632 sinkfp = popen(cmd, "w");
635 /* this will fail quietly if we didn't start as root */
637 #endif /* HAVE_SETEUID */
641 error(0, 0, "MDA open failed");
645 sigchld = signal(SIGCHLD, SIG_DFL);
649 char *ap, *ctt, options[MSGBUFSIZE];
652 /* build a connection to the SMTP listener */
653 if (!ctl->mda && ((sinkfp = smtp_open(ctl)) == NULL))
655 free_str_list(&xmit_names);
656 error(0, 0, "SMTP connect failed");
661 * Compute ESMTP options. It's a kluge to use nxtaddr()
662 * here because the contents of the Content-Transfer-Encoding
663 * headers isn't semantically an address. But it has the
664 * desired tokenizing effect.
667 if ((ctl->server.esmtp_options & ESMTP_8BITMIME)
669 && (ctt = nxtaddr(headers + ctt_offs)))
670 if (!strcasecmp(ctt,"7BIT"))
671 sprintf(options, " BODY=7BIT", ctt);
672 else if (!strcasecmp(ctt,"8BIT"))
673 sprintf(options, " BODY=8BITMIME", ctt);
674 if ((ctl->server.esmtp_options & ESMTP_SIZE) && !delimited)
675 sprintf(options + strlen(options), " SIZE=%d", len);
678 * If there is a Return-Path address on the message, this was
679 * almost certainly the MAIL FROM address given the originating
680 * sendmail. This is the best things to use for logging the
681 * message origin (it sets up the right behavior for bounces and
682 * mailing lists). Otherwise, take the From address.
684 * Try to get the SMTP listener to take the Return-Path or
685 * From address as MAIL FROM . If it won't, fall back on the
686 * calling-user ID. This won't affect replies, which use the
687 * header From address anyway.
689 * RFC 1123 requires that the domain name part of the
690 * MAIL FROM address be "canonicalized", that is a
691 * FQDN or MX but not a CNAME. We'll assume the From
692 * header is already in this form here (it certainly
693 * is if rewrite is on). RFC 1123 is silent on whether
694 * a nonexistent hostname part is considered canonical.
696 * This is a potential problem if the MTAs further upstream
697 * didn't pass canonicalized From/Return-Path lines, *and* the
698 * local SMTP listener insists on them. */
700 if (rtp_offs == -1 || !(ap = nxtaddr(headers + rtp_offs)))
701 if (from_offs == -1 || !(ap = nxtaddr(headers + from_offs)))
703 if (ap == (char *)NULL)
705 if (SMTP_from(sinkfp, ap, options) != SM_OK)
707 int smtperr = atoi(smtp_response);
710 error(0, 0, "SMTP error: %s", smtp_response);
713 * There'a one problem with this flow of control;
714 * there's no way to avoid reading the whole message
715 * off the server, even if the MAIL FROM response
716 * tells us that it's just to be discarded. We could
717 * fix this under IMAP by reading headers first, then
718 * trying to issue the MAIL FROM, and *then* reading
719 * the body...but POP3 can't do this.
724 case 571: /* unsolicited email refused */
726 * SMTP listener explicitly refuses to deliver
727 * mail coming from this address, probably due
728 * to an anti-spam domain exclusion. Respect
729 * this. Don't try to ship the message, and
730 * don't prevent it from being deleted.
732 sinkfp = (FILE *)NULL;
735 case 452: /* insufficient system storage */
737 * Temporary out-of-queue-space condition on the
738 * ESMTP server. Don't try to ship the message,
739 * and suppress deletion so it can be retried on
740 * a future retrieval cycle.
743 sinkfp = (FILE *)NULL;
744 SMTP_rset(sockfp); /* required by RFC1870 */
747 case 552: /* message exceeds fixed maximum message size */
749 * Permanent no-go condition on the
750 * ESMTP server. Don't try to ship the message,
751 * and allow it to be deleted.
753 sinkfp = (FILE *)NULL;
754 SMTP_rset(sockfp); /* required by RFC1870 */
757 default: /* retry with invoking user's address */
758 if (SMTP_from(sinkfp, user, options) != SM_OK)
760 error(0,0,"SMTP error: %s", smtp_response);
761 return(PS_SMTP); /* should never happen */
767 * Now list the recipient addressees
769 * RFC 1123 requires that the domain name part of the
770 * RCPT TO address be "canonicalized", that is a FQDN
771 * or MX but not a CNAME. RFC1123 doesn't say whether
772 * the FQDN part can be null (as it frequently will be
773 * here), but it's hard to see how this could cause a
776 for (idp = xmit_names; idp; idp = idp->next)
777 if (SMTP_rcpt(sinkfp, idp->id) == SM_OK)
784 "SMTP listener doesn't like recipient address `%s'", idp->id);
786 if (!good_addresses && SMTP_rcpt(sinkfp, user) != SM_OK)
789 "can't even send to calling user!");
793 /* tell it we're ready to send data */
799 /* we may need to strip carriage returns */
804 for (sp = tp = headers; *sp; sp++)
811 /* write all the headers */
815 n = fwrite(headers, 1, strlen(headers), sinkfp);
817 n = SockWrite(headers, 1, strlen(headers), sinkfp);
823 error(0, errno, "writing RFC822 headers");
827 signal(SIGCHLD, sigchld);
831 else if (outlevel == O_VERBOSE)
837 /* write error notifications */
838 #ifdef HAVE_RES_SEARCH
839 if (no_local_matches || bad_addresses)
842 #endif /* HAVE_RES_SEARCH */
845 char errhd[USERNAMELEN + POPBUFSIZE], *errmsg;
848 (void) strcpy(errhd, "X-Fetchmail-Warning: ");
849 #ifdef HAVE_RES_SEARCH
850 if (no_local_matches)
852 strcat(errhd, "no recipient addresses matched declared local names");
856 #endif /* HAVE_RES_SEARCH */
860 strcat(errhd, "SMTP listener rejected local recipient addresses: ");
861 errlen = strlen(errhd);
862 for (idp = xmit_names; idp; idp = idp->next)
864 errlen += strlen(idp->id) + 2;
866 errmsg = alloca(errlen+3);
867 (void) strcpy(errmsg, errhd);
868 for (idp = xmit_names; idp; idp = idp->next)
871 strcat(errmsg, idp->id);
873 strcat(errmsg, ", ");
877 strcat(errmsg, "\n");
879 /* we may need to strip carriage returns */
884 for (sp = tp = errmsg; *sp; sp++)
890 /* ship out the error line */
894 fwrite(errmsg, 1, strlen(errmsg), sinkfp);
896 SockWrite(errmsg, 1, strlen(errmsg), sinkfp);
900 free_str_list(&xmit_names);
902 /* issue the delimiter line */
908 SockWrite("\r\n", 1, 2, sinkfp);
912 * Body processing starts here
915 /* pass through the text lines */
916 while (delimited || remaining > 0)
918 if (!SockGets(buf, sizeof(buf)-1, sockfp))
920 vtalarm(ctl->server.timeout);
922 /* write the message size dots */
923 if ((n = strlen(buf)) > 0)
926 while (sizeticker >= SIZETICKER)
928 if (outlevel > O_SILENT)
930 sizeticker -= SIZETICKER;
935 /* check for end of message */
936 if (delimited && *buf == '.')
937 if (buf[1] == '\r' && buf[2] == '\n')
940 /* ship out the text line */
943 /* SMTP byte-stuffing */
948 SockWrite(buf, 1, 1, sinkfp);
950 /* we may need to strip carriage returns */
955 for (sp = tp = buf; *sp; sp++)
961 /* ship the text line */
963 n = fwrite(buf, 1, strlen(buf), sinkfp);
965 n = SockWrite(buf, 1, strlen(buf), sinkfp);
969 error(0, errno, "writing message text");
973 signal(SIGCHLD, sigchld);
977 else if (outlevel == O_VERBOSE)
983 * End-of-message processing starts here
986 if (outlevel == O_VERBOSE)
993 /* close the delivery pipe, we'll reopen before next message */
995 signal(SIGCHLD, sigchld);
998 error(0, 0, "MDA exited abnormally or returned nonzero status");
1004 /* write message terminator */
1005 if (SMTP_eom(sinkfp) != SM_OK)
1007 error(0, 0, "SMTP listener refused delivery");
1008 return(PS_TRANSIENT);
1012 return(delete_ok ? PS_SUCCESS : PS_TRANSIENT);
1017 kerberos_auth (socket, canonical)
1018 /* authenticate to the server host using Kerberos V4 */
1019 int socket; /* socket to server host */
1020 const char *canonical; /* server name */
1022 char * host_primary;
1026 Key_schedule schedule;
1029 ticket = ((KTEXT) (malloc (sizeof (KTEXT_ST))));
1030 rem = (krb_sendauth (0L, socket, ticket, "pop",
1032 ((char *) (krb_realmofhost (canonical))),
1033 ((unsigned long) 0),
1037 ((struct sockaddr_in *) 0),
1038 ((struct sockaddr_in *) 0),
1041 if (rem != KSUCCESS)
1043 error(0, 0, "kerberos error %s", (krb_get_err_text (rem)));
1048 #endif /* KERBEROS_V4 */
1050 int do_protocol(ctl, proto)
1051 /* retrieve messages from server using given protocol method table */
1052 struct query *ctl; /* parsed options with merged-in defaults */
1053 const struct method *proto; /* protocol method table */
1056 char *msg, *sp, *cp, realname[HOSTLEN];
1060 if (ctl->server.authenticate == A_KERBEROS)
1062 error(0, 0, "Kerberos support not linked.");
1065 #endif /* KERBEROS_V4 */
1067 /* lacking methods, there are some options that may fail */
1070 /* check for unsupported options */
1073 "Option --flush is not supported with %s",
1077 else if (ctl->fetchall) {
1079 "Option --all is not supported with %s",
1084 if (!proto->getsizes && ctl->limit)
1087 "Option --limit is not supported with %s",
1094 tag[0] = '\0'; /* nuke any tag hanging out from previous query */
1096 error_init(poll_interval == 0 && !logfile);
1098 /* set up the server-nonresponse timeout */
1099 sigsave = signal(SIGVTALRM, vtalarm_handler);
1100 vtalarm(mytimeout = ctl->server.timeout);
1102 if ((js = setjmp(restart)) == 1)
1105 "timeout after %d seconds waiting for %s.",
1106 ctl->server.timeout, ctl->server.names->id);
1111 /* error message printed at point of longjmp */
1116 char buf [POPBUFSIZE+1];
1117 int *msgsizes, len, num, count, new, deletions = 0;
1119 /* execute pre-initialization command, if any */
1120 if (ctl->preconnect && (ok = system(ctl->preconnect)))
1122 sprintf(buf, "pre-connection command failed with status %d", ok);
1128 /* open a socket to the mail server */
1129 if (!(sockfp = SockOpen(ctl->server.names->id,
1130 ctl->server.port ? ctl->server.port : protocol->port)))
1132 #ifndef EHOSTUNREACH
1133 #define EHOSTUNREACH (-1)
1135 if (outlevel == O_VERBOSE || errno != EHOSTUNREACH)
1136 error(0, errno, "connecting to host");
1142 if (ctl->server.authenticate == A_KERBEROS)
1144 ok = kerberos_auth(fileno(sockfp), ctl->server.canonical_name);
1147 vtalarm(ctl->server.timeout);
1149 #endif /* KERBEROS_V4 */
1151 /* accept greeting message from mail server */
1152 ok = (protocol->parse_response)(sockfp, buf);
1155 vtalarm(ctl->server.timeout);
1158 * Try to parse the host's actual name out of the greeting
1159 * message. We do this so that the progress messages will
1160 * make sense even if the connection is indirected through
1161 * ssh. *Do* use this for hacking reply headers, but *don't*
1162 * use it for error logging, as the names in the log should
1163 * correlate directly back to rc file entries.
1165 * This assumes that the first space-delimited token found
1166 * that contains at least two dots (with the characters on
1167 * each side of the dot alphanumeric to exclude version
1168 * numbers) is the hostname. The hostname candidate may not
1169 * contain @ -- if it does it's probably a mailserver
1170 * maintainer's name. If no such token is found, fall back on
1171 * the .fetchmailrc id.
1174 for (cp = buf; *cp; cp++)
1178 case 0: /* skip to end of current token */
1183 case 1: /* look for blank-delimited token */
1191 case 2: /* look for first dot */
1194 else if (*cp == ' ')
1196 else if (*cp == '.' && isalpha(cp[1]) && isalpha(cp[-1]))
1200 case 3: /* look for second dot */
1203 else if (*cp == ' ')
1205 else if (*cp == '.' && isalpha(cp[1]) && isalpha(cp[-1]))
1209 case 4: /* look for trailing space */
1212 else if (*cp == ' ')
1223 char *tp = realname;
1230 strcpy(realname, ctl->server.names->id);
1232 /* try to get authorized to fetch mail */
1233 if (protocol->getauth)
1235 shroud = ctl->password;
1236 ok = (protocol->getauth)(sockfp, ctl, buf);
1237 shroud = (char *)NULL;
1242 error(0, 0, "Authorization failure on %s@%s",
1247 vtalarm(ctl->server.timeout);
1250 /* compute number of messages and number of new messages waiting */
1251 ok = (protocol->getrange)(sockfp, ctl, &count, &new);
1254 vtalarm(ctl->server.timeout);
1256 /* show user how many messages we downloaded */
1257 if (outlevel > O_SILENT)
1258 if (count == -1) /* only used for ETRN */
1259 error(0, 0, "Polling %s@%s",
1262 else if (count == 0)
1263 error(0, 0, "No mail at %s@%s",
1268 if (new != -1 && (count - new) > 0)
1269 error(0, 0, "%d message%s (%d seen) at %s@%s.",
1270 count, count > 1 ? "s" : "", count-new,
1274 error(0, 0, "%d message%s at %s@%s.",
1275 count, count > 1 ? "s" : "",
1280 /* we may need to get sizes in order to check message limits */
1281 msgsizes = (int *)NULL;
1282 if (!ctl->fetchall && proto->getsizes && ctl->limit)
1284 msgsizes = (int *)alloca(sizeof(int) * count);
1286 ok = (proto->getsizes)(sockfp, count, msgsizes);
1289 vtalarm(ctl->server.timeout);
1294 if (new == -1 || ctl->fetchall)
1296 ok = ((new > 0) ? PS_SUCCESS : PS_NOMAIL);
1301 int force_retrieval, fetches;
1304 * What forces this code is that in POP3 and IMAP2BIS you can't
1305 * fetch a message without having it marked `seen'. In IMAP4,
1306 * on the other hand, you can (peek_capable is set to convey
1309 * The result of being unable to peek is that if there's
1310 * any kind of transient error (DNS lookup failure, or
1311 * sendmail refusing delivery due to process-table limits)
1312 * the message will be marked "seen" on the server without
1313 * having been delivered. This is not a big problem if
1314 * fetchmail is running in foreground, because the user
1315 * will see a "skipped" message when it next runs and get
1318 * But in daemon mode this leads to the message being silently
1319 * ignored forever. This is not acceptable.
1321 * We compensate for this by checking the error count from the
1322 * previous pass and forcing all messages to be considered new
1325 force_retrieval = !peek_capable && (ctl->errcount > 0);
1327 ctl->errcount = fetches = 0;
1329 /* read, forward, and delete messages */
1330 for (num = 1; num <= count; num++)
1332 int toolarge = msgsizes && (msgsizes[num-1] > ctl->limit);
1333 int fetch_it = ctl->fetchall ||
1334 (!toolarge && (force_retrieval || !(protocol->is_old && (protocol->is_old)(sockfp,ctl,num))));
1335 int suppress_delete = FALSE;
1337 /* we may want to reject this message if it's old */
1340 if (outlevel > O_SILENT)
1342 error_build("skipping message %d", num);
1344 error_build(" (oversized, %d bytes)", msgsizes[num-1]);
1349 /* request a message */
1350 ok = (protocol->fetch)(sockfp, ctl, num, &len);
1353 vtalarm(ctl->server.timeout);
1355 if (outlevel > O_SILENT)
1357 error_build("reading message %d", num);
1359 error_build(" (%d bytes)", len);
1360 if (outlevel == O_VERBOSE)
1361 error_complete(0, 0, "");
1366 /* read the message and ship it to the output sink */
1367 ok = gen_readmsg(sockfp,
1369 protocol->delimited,
1372 if (ok == PS_TRANSIENT)
1373 suppress_delete = TRUE;
1376 vtalarm(ctl->server.timeout);
1378 /* tell the server we got it OK and resynchronize */
1379 if (protocol->trail)
1381 ok = (protocol->trail)(sockfp, ctl, num);
1384 vtalarm(ctl->server.timeout);
1391 * At this point in flow of control, either we've bombed
1392 * on a protocol error or had delivery refused by the SMTP
1393 * server (unlikely -- I've never seen it) or we've seen
1394 * `accepted for delivery' and the message is shipped.
1395 * It's safe to mark the message seen and delete it on the
1399 /* maybe we delete this message now? */
1400 if (protocol->delete
1402 && (fetch_it ? !ctl->keep : ctl->flush))
1405 if (outlevel > O_SILENT)
1406 error_complete(0, 0, " flushed");
1407 ok = (protocol->delete)(sockfp, ctl, num);
1410 vtalarm(ctl->server.timeout);
1411 delete_str(&ctl->newsaved, num);
1413 else if (outlevel > O_SILENT)
1414 error_complete(0, 0, " not flushed");
1416 /* perhaps this as many as we're ready to handle */
1417 if (ctl->fetchlimit && ctl->fetchlimit <= fetches)
1421 ok = gen_transact(sockfp, protocol->exit_cmd);
1429 ok = gen_transact(sockfp, protocol->exit_cmd);
1438 vtalarm(ctl->server.timeout);
1439 if (ok != 0 && ok != PS_SOCKET)
1440 gen_transact(sockfp, protocol->exit_cmd);
1451 msg = "authorization";
1454 msg = "missing or bad RFC822 header";
1460 msg = "client/server synchronization";
1463 msg = "client/server protocol";
1466 msg = "SMTP transaction";
1469 error(0, 0, "undefined");
1472 if (ok==PS_SOCKET || ok==PS_AUTHFAIL || ok==PS_SYNTAX || ok==PS_IOERR
1473 || ok==PS_ERROR || ok==PS_PROTOCOL || ok==PS_SMTP)
1474 error(0, 0, "%s error while fetching from %s", msg, ctl->server.names->id);
1477 signal(SIGVTALRM, sigsave);
1481 #if defined(HAVE_STDARG_H)
1482 void gen_send(FILE *sockfp, char *fmt, ... )
1483 /* assemble command in printf(3) style and send to the server */
1485 void gen_send(sockfp, fmt, va_alist)
1486 /* assemble command in printf(3) style and send to the server */
1487 FILE *sockfp; /* socket to which server is connected */
1488 const char *fmt; /* printf-style format */
1492 char buf [POPBUFSIZE+1];
1495 if (protocol->tagged)
1496 (void) sprintf(buf, "%s ", GENSYM);
1500 #if defined(HAVE_STDARG_H)
1505 vsprintf(buf + strlen(buf), fmt, ap);
1508 strcat(buf, "\r\n");
1509 SockWrite(buf, 1, strlen(buf), sockfp);
1511 if (outlevel == O_VERBOSE)
1515 if (shroud && shroud[0] && (cp = strstr(buf, shroud)))
1519 sp = cp + strlen(shroud);
1525 buf[strlen(buf)-2] = '\0';
1526 error(0, 0, "%s> %s", protocol->name, buf);
1530 int gen_recv(sockfp, buf, size)
1531 /* get one line of input from the server */
1532 FILE *sockfp; /* socket to which server is connected */
1533 char *buf; /* buffer to receive input */
1534 int size; /* length of buffer */
1536 if (!SockGets(buf, size, sockfp))
1540 if (buf[strlen(buf)-1] == '\n')
1541 buf[strlen(buf)-1] = '\0';
1542 if (buf[strlen(buf)-1] == '\r')
1543 buf[strlen(buf)-1] = '\r';
1544 if (outlevel == O_VERBOSE)
1545 error(0, 0, "%s< %s", protocol->name, buf);
1550 #if defined(HAVE_STDARG_H)
1551 int gen_transact(FILE *sockfp, char *fmt, ... )
1552 /* assemble command in printf(3) style, send to server, accept a response */
1554 int gen_transact(sockfp, fmt, va_alist)
1555 /* assemble command in printf(3) style, send to server, accept a response */
1556 FILE *sockfp; /* socket to which server is connected */
1557 const char *fmt; /* printf-style format */
1562 char buf [POPBUFSIZE+1];
1565 if (protocol->tagged)
1566 (void) sprintf(buf, "%s ", GENSYM);
1570 #if defined(HAVE_STDARG_H)
1575 vsprintf(buf + strlen(buf), fmt, ap);
1578 strcat(buf, "\r\n");
1579 SockWrite(buf, 1, strlen(buf), sockfp);
1581 if (outlevel == O_VERBOSE)
1585 if (shroud && shroud[0] && (cp = strstr(buf, shroud)))
1589 sp = cp + strlen(shroud);
1595 buf[strlen(buf)-1] = '\0';
1596 error(0, 0, "%s> %s", protocol->name, buf);
1599 /* we presume this does its own response echoing */
1600 ok = (protocol->parse_response)(sockfp, buf);
1606 /* driver.c ends here */