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.
15 #endif /* HAVE_MEMORY_H */
16 #if defined(STDC_HEADERS)
20 #if defined(HAVE_UNISTD_H)
23 #if defined(HAVE_SYS_ITIMER_H)
24 #include <sys/itimer.h>
29 #ifdef HAVE_NET_SOCKET_H
30 #include <net/socket.h>
36 #if defined(HAVE_RES_SEARCH) || defined(HAVE_GETHOSTBYNAME)
39 #endif /* defined(HAVE_RES_SEARCH) || defined(HAVE_GETHOSTBYNAME) */
43 #include <netinet/in.h>
44 #endif /* KERBEROS_V4 */
49 #include "fetchmail.h"
52 /* throw types for runtime errors */
53 #define THROW_TIMEOUT 1 /* server timed out */
54 #define THROW_SIGPIPE 2 /* SIGPIPE on stream socket */
56 /* magic values for the message length array */
57 #define MSGLEN_UNKNOWN 0 /* length unknown (0 is impossible) */
58 #define MSGLEN_INVALID -1 /* length passed back is invalid */
59 #define MSGLEN_TOOLARGE -2 /* message is too large */
60 #define MSGLEN_OLD -3 /* message is old */
62 int pass; /* how many times have we re-polled? */
63 int stage; /* where are we? */
64 int phase; /* where are we, for error-logging purposes? */
65 int batchcount; /* count of messages sent in current batch */
66 flag peek_capable; /* can we peek for better error recovery? */
67 int mailserver_socket_temp; /* socket to free if connect timeout */
69 static int timeoutcount; /* count consecutive timeouts */
71 static jmp_buf restart;
73 void set_timeout(int timeleft)
74 /* reset the nonresponse-timeout */
76 #if !defined(__EMX__) && !defined(__BEOS__)
77 struct itimerval ntimeout;
82 ntimeout.it_interval.tv_sec = ntimeout.it_interval.tv_usec = 0;
83 ntimeout.it_value.tv_sec = timeleft;
84 ntimeout.it_value.tv_usec = 0;
85 setitimer(ITIMER_REAL, &ntimeout, (struct itimerval *)NULL);
89 static void timeout_handler (int signal)
90 /* handle SIGALRM signal indicating a server timeout */
93 longjmp(restart, THROW_TIMEOUT);
96 static void sigpipe_handler (int signal)
97 /* handle SIGPIPE signal indicating a broken stream socket */
99 longjmp(restart, THROW_SIGPIPE);
102 /* ignore SIGALRM signal indicating a timeout during cleanup */
103 static void cleanup_timeout_handler (int signal) { }
105 #define CLEANUP_TIMEOUT 60 /* maximum timeout during cleanup */
107 static int cleanupSockClose (int fd)
108 /* close sockets in maximum CLEANUP_TIMEOUT seconds during cleanup */
111 void (*alrmsave)(int);
112 alrmsave = signal(SIGALRM, cleanup_timeout_handler);
113 set_timeout(CLEANUP_TIMEOUT);
114 scerror = SockClose(fd);
116 signal(SIGALRM, alrmsave);
121 static int kerberos_auth(socket, canonical, principal)
122 /* authenticate to the server host using Kerberos V4 */
123 int socket; /* socket to server host */
124 char *canonical; /* server name */
131 Key_schedule schedule;
133 char * prin_copy = (char *) NULL;
134 char * prin = (char *) NULL;
135 char * inst = (char *) NULL;
136 char * realm = (char *) NULL;
138 if (principal != (char *)NULL && *principal)
141 prin = prin_copy = xstrdup(principal);
142 for (cp = prin_copy; *cp && *cp != '.'; ++cp)
148 while (*cp && *cp != '@')
158 xalloca(ticket, KTEXT, sizeof (KTEXT_ST));
159 rem = (krb_sendauth (0L, socket, ticket,
161 inst ? inst : canonical,
162 realm ? realm : ((char *) (krb_realmofhost (canonical))),
167 ((struct sockaddr_in *) 0),
168 ((struct sockaddr_in *) 0),
176 report(stderr, GT_("kerberos error %s\n"), (krb_get_err_text (rem)));
177 return (PS_AUTHFAIL);
181 #endif /* KERBEROS_V4 */
184 static int kerberos5_auth(socket, canonical)
185 /* authenticate to the server host using Kerberos V5 */
186 int socket; /* socket to server host */
187 const char *canonical; /* server name */
189 krb5_error_code retval;
190 krb5_context context;
192 krb5_principal client = NULL, server = NULL;
193 krb5_error *err_ret = NULL;
195 krb5_auth_context auth_context = NULL;
197 krb5_init_context(&context);
198 krb5_init_ets(context);
199 krb5_auth_con_init(context, &auth_context);
201 if (retval = krb5_cc_default(context, &ccdef)) {
202 report(stderr, "krb5_cc_default: %s\n", error_message(retval));
206 if (retval = krb5_cc_get_principal(context, ccdef, &client)) {
207 report(stderr, "krb5_cc_get_principal: %s\n", error_message(retval));
211 if (retval = krb5_sname_to_principal(context, canonical, "pop",
214 report(stderr, "krb5_sname_to_principal: %s\n", error_message(retval));
218 retval = krb5_sendauth(context, &auth_context, (krb5_pointer) &socket,
219 "KPOPV1.0", client, server,
220 AP_OPTS_MUTUAL_REQUIRED,
221 NULL, /* no data to checksum */
222 0, /* no creds, use ccache instead */
226 NULL); /* don't need reply */
228 krb5_free_principal(context, server);
229 krb5_free_principal(context, client);
230 krb5_auth_con_free(context, auth_context);
234 if (err_ret && err_ret->e_text) {
235 report(stderr, GT_("krb5_sendauth: %s [server says '%*s'] \n"),
236 error_message(retval),
239 if (err_ret && err_ret->text.length) {
240 report(stderr, GT_("krb5_sendauth: %s [server says '%*s'] \n"),
241 error_message(retval),
242 err_ret->text.length,
245 krb5_free_error(context, err_ret);
247 report(stderr, "krb5_sendauth: %s\n", error_message(retval));
253 #endif /* KERBEROS_V5 */
255 static void clean_skipped_list(struct idlist **skipped_list)
256 /* struct "idlist" contains no "prev" ptr; we must remove unused items first */
258 struct idlist *current=NULL, *prev=NULL, *tmp=NULL, *head=NULL;
259 prev = current = head = *skipped_list;
265 /* if item has no reference, remove it */
266 if (current && current->val.status.mark == 0)
268 if (current == head) /* remove first item (head) */
270 head = current->next;
271 if (current->id) free(current->id);
273 prev = current = head;
275 else /* remove middle/last item */
279 if (current->id) free(current->id);
284 else /* skip this item */
287 current = current->next;
291 *skipped_list = head;
294 static void send_size_warnings(struct query *ctl)
295 /* send warning mail with skipped msg; reset msg count when user notified */
298 int msg_to_send = FALSE;
299 struct idlist *head=NULL, *current=NULL;
300 int max_warning_poll_count;
306 /* don't start a notification message unless we need to */
307 for (current = head; current; current = current->next)
308 if (current->val.status.num == 0 && current->val.status.mark)
314 * There's no good way to recover if we can't send notification mail,
315 * but it's not a disaster, either, since the skipped mail will not
318 if (open_warning_by_mail(ctl, (struct msgblk *)NULL))
321 GT_("Subject: Fetchmail oversized-messages warning.\r\n"
323 "The following oversized messages remain on the mail server %s:"),
324 ctl->server.pollname);
326 if (run.poll_interval == 0)
327 max_warning_poll_count = 0;
329 max_warning_poll_count = ctl->warnings/run.poll_interval;
331 /* parse list of skipped msg, adding items to the mail */
332 for (current = head; current; current = current->next)
334 if (current->val.status.num == 0 && current->val.status.mark)
336 nbr = current->val.status.mark;
337 size = atoi(current->id);
339 GT_("\t%d msg %d octets long skipped by fetchmail.\r\n"),
342 current->val.status.num++;
343 current->val.status.mark = 0;
345 if (current->val.status.num >= max_warning_poll_count)
346 current->val.status.num = 0;
349 close_warning_by_mail(ctl, (struct msgblk *)NULL);
352 static void mark_oversized(struct query *ctl, int num, int size)
353 /* mark a message oversized */
355 struct idlist *current=NULL, *tmp=NULL;
359 /* convert size to string */
361 snprintf(sizestr, sizeof(sizestr),
364 #endif /* HAVE_SNPRINTF */
367 /* build a list of skipped messages
368 * val.id = size of msg (string cnvt)
369 * val.status.num = warning_poll_count
370 * val.status.mask = nbr of msg this size
373 current = ctl->skipped;
375 /* initialise warning_poll_count to the
376 * current value so that all new msg will
377 * be included in the next mail
379 cnt = current ? current->val.status.num : 0;
381 /* if entry exists, increment the count */
382 if (current && str_in_list(¤t, sizestr, FALSE))
384 for ( ; current; current = current->next)
386 if (strcmp(current->id, sizestr) == 0)
388 current->val.status.mark++;
393 /* otherwise, create a new entry */
394 /* initialise with current poll count */
397 tmp = save_str(&ctl->skipped, sizestr, 1);
398 tmp->val.status.num = cnt;
402 static int fetch_messages(int mailserver_socket, struct query *ctl,
403 int count, int *msgsizes, int *msgcodes, int maxfetch,
404 int *fetches, int *dispatches, int *deletions)
405 /* fetch messages in lockstep mode */
409 for (num = 1; num <= count; num++)
411 flag suppress_delete = FALSE;
412 flag suppress_forward = FALSE;
413 flag suppress_readbody = FALSE;
414 flag retained = FALSE;
416 if (msgcodes[num-1] < 0)
418 if ((msgcodes[num-1] == MSGLEN_TOOLARGE) && !check_only)
419 mark_oversized(ctl, num, msgsizes[num-1]);
420 if (outlevel > O_SILENT)
423 GT_("skipping message %s@%s:%d (%d octets)"),
424 ctl->remotename, ctl->server.truename, num,
426 switch (msgcodes[num-1])
430 * Invalid lengths are produced by Post Office/NT's
431 * annoying habit of randomly prepending bogus
432 * LIST items of length -1. Patrick Audley
433 * <paudley@pobox.com> tells us: LIST shows a
434 * size of -1, RETR and TOP return "-ERR
435 * System error - couldn't open message", and
436 * DELE succeeds but doesn't actually delete
439 report_build(stdout, GT_(" (length -1)"));
441 case MSGLEN_TOOLARGE:
443 GT_(" (oversized, %d octets)"),
451 flag wholesize = !ctl->server.base_protocol->fetch_body;
453 /* request a message */
454 err = (ctl->server.base_protocol->fetch_headers)(mailserver_socket,ctl,num, &len);
455 if (err == PS_TRANSIENT) /* server is probably Exchange */
458 GT_("couldn't fetch headers, message %s@%s:%d (%d octets)"),
459 ctl->remotename, ctl->server.truename, num,
466 /* -1 means we didn't see a size in the response */
469 len = msgsizes[num - 1];
473 if (outlevel > O_SILENT)
475 report_build(stdout, GT_("reading message %s@%s:%d of %d"),
476 ctl->remotename, ctl->server.truename,
480 report_build(stdout, GT_(" (%d %soctets)"),
481 len, wholesize ? "" : GT_("header "));
482 if (outlevel >= O_VERBOSE)
483 report_complete(stdout, "\n");
485 report_complete(stdout, " ");
489 * Read the message headers and ship them to the
492 err = readheaders(mailserver_socket, len, msgsizes[num-1],
494 if (err == PS_RETAINED)
495 suppress_forward = retained = TRUE;
496 else if (err == PS_TRANSIENT)
497 suppress_delete = suppress_forward = TRUE;
498 else if (err == PS_REFUSED)
499 suppress_forward = TRUE;
502 * readheaders does not read the body when it
503 * hits a non-header. It has been recently
504 * fixed to return PS_TRUNCATED (properly) when
505 * that happens, but apparently fixing that bug
506 * opened this one here (which looks like an
507 * inproper fix from some ancient thinko)
509 else if (err == PS_TRUNCATED)
510 suppress_readbody = TRUE;
514 else if (err && err != PS_TRUNCATED)
519 * If we're using IMAP4 or something else that
520 * can fetch headers separately from bodies,
521 * it's time to request the body now. This
522 * fetch may be skipped if we got an anti-spam
523 * or other PS_REFUSED error response during
526 if (ctl->server.base_protocol->fetch_body && !suppress_readbody)
528 if (outlevel >= O_VERBOSE && !isafile(1))
534 if ((err = (ctl->server.base_protocol->trail)(mailserver_socket, ctl, num)))
537 if (!suppress_forward)
539 if ((err=(ctl->server.base_protocol->fetch_body)(mailserver_socket,ctl,num,&len)))
542 * Work around a bug in Novell's
543 * broken GroupWise IMAP server;
544 * its body FETCH response is missing
545 * the required length for the data
546 * string. This violates RFC2060.
549 len = msgsizes[num-1] - msgblk.msglen;
550 if (outlevel > O_SILENT && !wholesize)
551 report_complete(stdout,
552 GT_(" (%d body octets) "), len);
556 /* process the body now */
559 if (suppress_readbody)
565 err = readbody(mailserver_socket,
570 if (err == PS_TRANSIENT)
571 suppress_delete = suppress_forward = TRUE;
575 /* tell server we got it OK and resynchronize */
576 if (ctl->server.base_protocol->trail)
578 if (outlevel >= O_VERBOSE && !isafile(1))
584 err = (ctl->server.base_protocol->trail)(mailserver_socket, ctl, num);
590 /* count # messages forwarded on this pass */
591 if (!suppress_forward)
595 * Check to see if the numbers matched?
597 * Yes, some servers foo this up horribly.
598 * All IMAP servers seem to get it right, and
599 * so does Eudora QPOP at least in 2.xx
602 * Microsoft Exchange gets it completely
603 * wrong, reporting compressed rather than
604 * actual sizes (so the actual length of
605 * message is longer than the reported size).
606 * Another fine example of Microsoft brain death!
608 * Some older POP servers, like the old UCB
609 * POP server and the pre-QPOP QUALCOMM
610 * versions, report a longer size in the LIST
611 * response than actually gets shipped up.
612 * It's unclear what is going on here, as the
613 * QUALCOMM server (at least) seems to be
614 * reporting the on-disk size correctly.
616 if (msgblk.msglen != msgsizes[num-1])
618 if (outlevel >= O_DEBUG)
620 GT_("message %s@%s:%d was not the expected length (%d actual != %d expected)\n"),
621 ctl->remotename, ctl->server.truename, num,
622 msgblk.msglen, msgsizes[num-1]);
625 /* end-of-message processing starts here */
626 if (!close_sink(ctl, &msgblk, !suppress_forward))
629 suppress_delete = TRUE;
635 * At this point in flow of control, either
636 * we've bombed on a protocol error or had
637 * delivery refused by the SMTP server
638 * (unlikely -- I've never seen it) or we've
639 * seen `accepted for delivery' and the
640 * message is shipped. It's safe to mark the
641 * message seen and delete it on the server
646 * Tell the UID code we've seen this.
647 * Matthias Andree: only register the UID if we could actually
648 * forward this mail. If we omit this !suppress_delete check,
649 * fetchmail will never retry mail that the local listener
650 * refused temporarily.
652 if (ctl->newsaved && !suppress_delete)
656 for (sdp = ctl->newsaved; sdp; sdp = sdp->next)
657 if ((sdp->val.status.num == num) && (msgcodes[num-1] >= 0))
659 sdp->val.status.mark = UID_SEEN;
660 save_str(&ctl->oldsaved, sdp->id,UID_SEEN);
664 /* maybe we delete this message now? */
667 if (outlevel > O_SILENT)
668 report(stdout, GT_(" retained\n"));
670 else if (ctl->server.base_protocol->delete
672 && ((msgcodes[num-1] >= 0) ? !ctl->keep : ctl->flush))
675 if (outlevel > O_SILENT)
676 report_complete(stdout, GT_(" flushed\n"));
677 err = (ctl->server.base_protocol->delete)(mailserver_socket, ctl, num);
681 delete_str(&ctl->newsaved, num);
682 #endif /* POP3_ENABLE */
684 else if (outlevel > O_SILENT)
685 report_complete(stdout, GT_(" not flushed\n"));
687 /* perhaps this as many as we're ready to handle */
688 if (maxfetch && maxfetch <= *fetches && *fetches < count)
690 report(stdout, GT_("fetchlimit %d reached; %d messages left on server %s account %s\n"),
691 maxfetch, count - *fetches, ctl->server.truename, ctl->remotename);
699 static int do_session(ctl, proto, maxfetch)
700 /* retrieve messages from server using given protocol method table */
701 struct query *ctl; /* parsed options with merged-in defaults */
702 const struct method *proto; /* protocol method table */
703 const int maxfetch; /* maximum number of messages to fetch */
707 volatile int err, mailserver_socket = -1; /* pacifies -Wall */
709 int err, mailserver_socket = -1;
710 #endif /* HAVE_VOLATILE */
712 void (*pipesave)(int);
713 void (*alrmsave)(int);
715 ctl->server.base_protocol = proto;
719 init_transact(proto);
721 /* set up the server-nonresponse timeout */
722 alrmsave = signal(SIGALRM, timeout_handler);
723 mytimeout = ctl->server.timeout;
725 /* set up the broken-pipe timeout */
726 pipesave = signal(SIGPIPE, sigpipe_handler);
728 if ((js = setjmp(restart)))
730 #ifdef HAVE_SIGPROCMASK
732 * Don't rely on setjmp() to restore the blocked-signal mask.
733 * It does this under BSD but is required not to under POSIX.
735 * If your Unix doesn't have sigprocmask, better hope it has
736 * BSD-like behavior. Otherwise you may see fetchmail get
737 * permanently wedged after a second timeout on a bad read,
738 * because alarm signals were blocked after the first.
742 sigfillset(&allsigs);
743 sigprocmask(SIG_UNBLOCK, &allsigs, NULL);
744 #endif /* HAVE_SIGPROCMASK */
746 /* If there was a connect timeout, the socket should be closed.
747 * mailserver_socket_temp contains the socket to close.
749 mailserver_socket = mailserver_socket_temp;
751 if (js == THROW_SIGPIPE)
753 signal(SIGPIPE, SIG_IGN);
755 GT_("SIGPIPE thrown from an MDA or a stream socket error\n"));
759 else if (js == THROW_TIMEOUT)
761 if (phase == OPEN_WAIT)
763 GT_("timeout after %d seconds waiting to connect to server %s.\n"),
764 ctl->server.timeout, ctl->server.pollname);
765 else if (phase == SERVER_WAIT)
767 GT_("timeout after %d seconds waiting for server %s.\n"),
768 ctl->server.timeout, ctl->server.pollname);
769 else if (phase == FORWARDING_WAIT)
771 GT_("timeout after %d seconds waiting for %s.\n"),
773 ctl->mda ? "MDA" : "SMTP");
774 else if (phase == LISTENER_WAIT)
776 GT_("timeout after %d seconds waiting for listener to respond.\n"), ctl->server.timeout);
779 GT_("timeout after %d seconds.\n"), ctl->server.timeout);
782 * If we've exceeded our threshold for consecutive timeouts,
783 * try to notify the user, then mark the connection wedged.
784 * Don't do this if the connection can idle, though; idle
785 * timeouts just mean the frequency of mail is low.
787 if (timeoutcount > MAX_TIMEOUTS
788 && !open_warning_by_mail(ctl, (struct msgblk *)NULL))
791 GT_("Subject: fetchmail sees repeated timeouts\r\n"));
793 GT_("Fetchmail saw more than %d timeouts while attempting to get mail from %s@%s.\r\n"),
796 ctl->server.truename);
798 GT_("This could mean that your mailserver is stuck, or that your SMTP\r\n" \
799 "server is wedged, or that your mailbox file on the server has been\r\n" \
800 "corrupted by a server error. You can run `fetchmail -v -v' to\r\n" \
801 "diagnose the problem.\r\n\r\n" \
802 "Fetchmail won't poll this mailbox again until you restart it.\r\n"));
803 close_warning_by_mail(ctl, (struct msgblk *)NULL);
810 /* try to clean up all streams */
813 if (mailserver_socket != -1) {
814 cleanupSockClose(mailserver_socket);
815 mailserver_socket = -1;
820 char buf[MSGBUFSIZE+1], *realhost;
821 int count, new, bytes, deletions = 0;
822 int *msgsizes = (int *)NULL;
823 int *msgcodes = (int *)NULL;
825 int fetches, dispatches, oldphase;
826 #else /* INET6_ENABLE */
827 int port, fetches, dispatches, oldphase;
828 #endif /* INET6_ENABLE */
831 /* execute pre-initialization command, if any */
832 if (ctl->preconnect && (err = system(ctl->preconnect)))
835 GT_("pre-connection command failed with status %d\n"), err);
840 /* open a socket to the mail server */
843 set_timeout(mytimeout);
846 port = ctl->server.port ? ctl->server.port : ( ctl->use_ssl ? ctl->server.base_protocol->sslport : ctl->server.base_protocol->port );
848 port = ctl->server.port ? ctl->server.port : ctl->server.base_protocol->port;
850 #endif /* !INET6_ENABLE */
853 /* If either the pollname or vianame are "hesiod" we want to
854 lookup the user's hesiod pobox host */
855 if (!strcasecmp(ctl->server.queryname, "hesiod")) {
856 struct hes_postoffice *hes_p;
857 hes_p = hes_getmailhost(ctl->remotename);
858 if (hes_p != NULL && strcmp(hes_p->po_type, "POP") == 0) {
859 free(ctl->server.queryname);
860 ctl->server.queryname = xstrdup(hes_p->po_host);
862 free(ctl->server.via);
863 ctl->server.via = xstrdup(hes_p->po_host);
866 GT_("couldn't find HESIOD pobox for %s\n"),
872 #ifdef HAVE_GETHOSTBYNAME
874 * Canonicalize the server truename for later use. This also
875 * functions as a probe for whether the mailserver is accessible.
876 * We try it on each poll cycle until we get a result. This way,
877 * fetchmail won't fail if started up when the network is inaccessible.
879 if (ctl->server.dns && !ctl->server.trueaddr)
881 if (ctl->server.lead_server)
883 char *leadname = ctl->server.lead_server->truename;
885 /* prevent core dump from ill-formed or duplicate entry */
888 report(stderr, GT_("Lead server has no name.\n"));
895 ctl->server.truename = xstrdup(leadname);
899 struct hostent *namerec;
902 * Get the host's IP, so we can report it like this:
904 * Received: from hostname [10.0.0.1]
907 namerec = gethostbyname(ctl->server.queryname);
908 if (namerec == (struct hostent *)NULL)
911 GT_("couldn't find canonical DNS name of %s\n"),
912 ctl->server.pollname);
920 ctl->server.truename=xstrdup((char *)namerec->h_name);
921 ctl->server.trueaddr=xmalloc(namerec->h_length);
922 memcpy(ctl->server.trueaddr,
923 namerec->h_addr_list[0],
928 #endif /* HAVE_GETHOSTBYNAME */
930 realhost = ctl->server.via ? ctl->server.via : ctl->server.pollname;
932 /* allow time for the port to be set up if we have a plugin */
933 if (ctl->server.plugin)
936 if ((mailserver_socket = SockOpen(realhost,
937 ctl->server.service ? ctl->server.service : ( ctl->use_ssl ? ctl->server.base_protocol->sslservice : ctl->server.base_protocol->service ),
938 ctl->server.netsec, ctl->server.plugin)) == -1)
939 #else /* INET6_ENABLE */
940 if ((mailserver_socket = SockOpen(realhost, port, NULL, ctl->server.plugin)) == -1)
941 #endif /* INET6_ENABLE */
946 #ifdef HAVE_RES_SEARCH
947 if (err_no != 0 && h_errno != 0)
948 report(stderr, GT_("internal inconsistency\n"));
951 * Avoid generating a bogus error every poll cycle when we're
952 * in daemon mode but the connection to the outside world
955 if (!((err_no == EHOSTUNREACH || err_no == ENETUNREACH)
956 && run.poll_interval))
958 report_build(stderr, GT_("%s connection to %s failed"),
959 ctl->server.base_protocol->name, ctl->server.pollname);
960 #ifdef HAVE_RES_SEARCH
963 if (h_errno == HOST_NOT_FOUND)
964 strcpy(errbuf, GT_("host is unknown."));
966 else if (h_errno == NO_ADDRESS)
967 strcpy(errbuf, GT_("name is valid but has no IP address."));
969 else if (h_errno == NO_RECOVERY)
970 strcpy(errbuf, GT_("unrecoverable name server error."));
971 else if (h_errno == TRY_AGAIN)
972 strcpy(errbuf, GT_("temporary name server error."));
975 snprintf(errbuf, sizeof(errbuf),
978 #endif /* HAVE_SNPRINTF */
979 GT_("unknown DNS error %d."), h_errno);
982 #endif /* HAVE_RES_SEARCH */
983 strcpy(errbuf, strerror(err_no));
984 report_complete(stderr, ": %s\n", errbuf);
988 * Don't use this. It was an attempt to address Debian bug
989 * #47143 (Notify user by mail when pop server nonexistent).
990 * Trouble is, that doesn't work; you trip over the case
991 * where your SLIP or PPP link is down...
993 /* warn the system administrator */
994 if (open_warning_by_mail(ctl, (struct msgblk *)NULL) == 0)
997 GT_("Subject: Fetchmail unreachable-server warning.\r\n"
999 "Fetchmail could not reach the mail server %s:")
1000 ctl->server.pollname);
1001 stuff_warning(ctl, errbuf, ctl->server.pollname);
1002 close_warning_by_mail(ctl, (struct msgblk *)NULL);
1006 #endif /* INET6_ENABLE */
1014 /* Save the socket opened. Usefull if Fetchmail hangs on SSLOpen
1015 * because the socket can be closed
1017 mailserver_socket_temp = mailserver_socket;
1018 set_timeout(mytimeout);
1020 /* perform initial SSL handshake on open connection */
1021 /* Note: We pass the realhost name over for certificate
1022 verification. We may want to make this configurable */
1023 if (ctl->use_ssl && SSLOpen(mailserver_socket,ctl->sslcert,ctl->sslkey,ctl->sslproto,ctl->sslcertck,
1024 ctl->sslcertpath,ctl->sslfingerprint,realhost,ctl->server.pollname) == -1)
1026 report(stderr, GT_("SSL connection failed.\n"));
1030 /* Fetchmail didn't hang on SSLOpen,
1031 * then no need to set mailserver_socket_temp
1033 mailserver_socket_temp = -1;
1036 /* A timeout is still defined before SSLOpen,
1037 * then Fetchmail hanging on SSLOpen is handled.
1042 if (ctl->server.authenticate == A_KERBEROS_V4)
1044 set_timeout(mytimeout);
1045 err = kerberos_auth(mailserver_socket, ctl->server.truename,
1046 ctl->server.principal);
1051 #endif /* KERBEROS_V4 */
1054 if (ctl->server.authenticate == A_KERBEROS_V5)
1056 set_timeout(mytimeout);
1057 err = kerberos5_auth(mailserver_socket, ctl->server.truename);
1062 #endif /* KERBEROS_V5 */
1064 /* accept greeting message from mail server */
1065 err = (ctl->server.base_protocol->parse_response)(mailserver_socket, buf);
1069 /* try to get authorized to fetch mail */
1070 stage = STAGE_GETAUTH;
1071 if (ctl->server.base_protocol->getauth)
1073 err = (ctl->server.base_protocol->getauth)(mailserver_socket, ctl, buf);
1077 if (err == PS_LOCKBUSY)
1078 report(stderr, GT_("Lock-busy error on %s@%s\n"),
1080 ctl->server.truename);
1081 else if (err == PS_SERVBUSY)
1082 report(stderr, GT_("Server busy error on %s@%s\n"),
1084 ctl->server.truename);
1085 else if (err == PS_AUTHFAIL)
1087 report(stderr, GT_("Authorization failure on %s@%s%s\n"),
1089 ctl->server.truename,
1090 (ctl->wehaveauthed ? GT_(" (previously authorized)") : "")
1094 * If we're running in background, try to mail the
1095 * calling user a heads-up about the authentication
1096 * failure once it looks like this isn't a fluke
1097 * due to the server being temporarily inaccessible.
1098 * When we get third succesive failure, we notify the user
1099 * but only if we haven't already managed to get
1100 * authorization. After that, once we get authorization
1101 * we let the user know service is restored.
1103 if (run.poll_interval
1104 && ctl->wehavesentauthnote
1105 && ((ctl->wehaveauthed && ++ctl->authfailcount == 10)
1106 || ++ctl->authfailcount == 3)
1107 && !open_warning_by_mail(ctl, (struct msgblk *)NULL))
1109 ctl->wehavesentauthnote = 1;
1111 GT_("Subject: fetchmail authentication failed on %s@%s\r\n"),
1112 ctl->remotename, ctl->server.truename);
1114 GT_("Fetchmail could not get mail from %s@%s.\r\n"),
1116 ctl->server.truename);
1117 if (ctl->wehaveauthed)
1118 stuff_warning(ctl, GT_("\
1119 The attempt to get authorization failed.\r\n\
1120 Since we have already succeeded in getting authorization for this\r\n\
1121 connection, this is probably another failure mode (such as busy server)\r\n\
1122 that fetchmail cannot distinguish because the server didn't send a useful\r\n\
1125 However, if you HAVE changed you account details since starting the\r\n\
1126 fetchmail daemon, you need to stop the daemon, change your configuration\r\n\
1127 of fetchmail, and then restart the daemon.\r\n\
1129 The fetchmail daemon will continue running and attempt to connect\r\n\
1130 at each cycle. No future notifications will be sent until service\r\n\
1133 stuff_warning(ctl, GT_("\
1134 The attempt to get authorization failed.\r\n\
1135 This probably means your password is invalid, but some servers have\r\n\
1136 other failure modes that fetchmail cannot distinguish from this\r\n\
1137 because they don't send useful error messages on login failure.\r\n\
1139 The fetchmail daemon will continue running and attempt to connect\r\n\
1140 at each cycle. No future notifications will be sent until service\r\n\
1142 close_warning_by_mail(ctl, (struct msgblk *)NULL);
1146 report(stderr, GT_("Unknown login or authentication error on %s@%s\n"),
1148 ctl->server.truename);
1155 * This connection has given us authorization at least once.
1157 * There are dodgy server (clubinternet.fr for example) that
1158 * give spurious authorization failures on patently good
1159 * account/password details, then 5 minutes later let you in!
1161 * This is meant to build in some tolerance of such nasty bits
1164 ctl->wehaveauthed = 1;
1165 /*if (ctl->authfailcount >= 3)*/
1166 if (ctl->wehavesentauthnote)
1168 ctl->wehavesentauthnote = 0;
1170 GT_("Authorization OK on %s@%s\n"),
1172 ctl->server.truename);
1173 if (!open_warning_by_mail(ctl, (struct msgblk *)NULL))
1176 GT_("Subject: fetchmail authentication OK on %s@%s\r\n"),
1177 ctl->remotename, ctl->server.truename);
1179 GT_("Fetchmail was able to log into %s@%s.\r\n"),
1181 ctl->server.truename);
1183 GT_("Service has been restored.\r\n"));
1184 close_warning_by_mail(ctl, (struct msgblk *)NULL);
1189 * Reporting only after the first three
1190 * consecutive failures, or ten consecutive
1191 * failures after we have managed to get
1194 ctl->authfailcount = 0;
1198 ctl->errcount = fetches = 0;
1200 /* now iterate over each folder selected */
1201 for (idp = ctl->mailboxes; idp; idp = idp->next)
1208 /* reset timeout, in case we did an IDLE */
1209 mytimeout = ctl->server.timeout;
1211 if (outlevel >= O_DEBUG)
1214 report(stdout, GT_("selecting or re-polling folder %s\n"), idp->id);
1216 report(stdout, GT_("selecting or re-polling default folder\n"));
1219 /* compute # of messages and number of new messages waiting */
1220 stage = STAGE_GETRANGE;
1221 err = (ctl->server.base_protocol->getrange)(mailserver_socket, ctl, idp->id, &count, &new, &bytes);
1225 /* show user how many messages we downloaded */
1227 #ifdef HAVE_SNPRINTF
1228 (void) snprintf(buf, sizeof(buf),
1231 #endif /* HAVE_SNPRINTF */
1232 GT_("%s at %s (folder %s)"),
1233 ctl->remotename, ctl->server.truename, idp->id);
1235 #ifdef HAVE_SNPRINTF
1236 (void) snprintf(buf, sizeof(buf),
1239 #endif /* HAVE_SNPRINTF */
1241 ctl->remotename, ctl->server.truename);
1242 if (outlevel > O_SILENT)
1244 if (count == -1) /* only used for ETRN */
1245 report(stdout, GT_("Polling %s\n"), ctl->server.truename);
1246 else if (count != 0)
1248 if (new != -1 && (count - new) > 0)
1249 report_build(stdout, GT_("%d %s (%d seen) for %s"),
1250 count, count > 1 ? GT_("messages") :
1254 report_build(stdout, GT_("%d %s for %s"),
1255 count, count > 1 ? GT_("messages") :
1256 GT_("message"), buf);
1258 report_complete(stdout, ".\n");
1260 report_complete(stdout, GT_(" (%d octets).\n"), bytes);
1264 /* these are pointless in normal daemon mode */
1265 if (pass == 1 && (run.poll_interval == 0 || outlevel >= O_VERBOSE))
1266 report(stdout, GT_("No mail for %s\n"), buf);
1270 /* very important, this is where we leave the do loop */
1276 if (new == -1 || ctl->fetchall)
1278 fetches = new; /* set error status correctly */
1280 * There used to be a `goto noerror' here, but this
1281 * prevented checking of multiple folders. This
1282 * comment is a reminder in case I introduced some
1283 * subtle bug by removing it...
1288 flag force_retrieval;
1292 * What forces this code is that in POP2 and
1293 * IMAP2bis you can't fetch a message without
1294 * having it marked `seen'. In POP3 and IMAP4, on the
1295 * other hand, you can (peek_capable is set by
1296 * each driver module to convey this; it's not a
1297 * method constant because of the difference between
1298 * IMAP2bis and IMAP4, and because POP3 doesn't peek
1299 * if fetchall is on).
1301 * The result of being unable to peek is that if there's
1302 * any kind of transient error (DNS lookup failure, or
1303 * sendmail refusing delivery due to process-table limits)
1304 * the message will be marked "seen" on the server without
1305 * having been delivered. This is not a big problem if
1306 * fetchmail is running in foreground, because the user
1307 * will see a "skipped" message when it next runs and get
1310 * But in daemon mode this leads to the message
1311 * being silently ignored forever. This is not
1314 * We compensate for this by checking the error
1315 * count from the previous pass and forcing all
1316 * messages to be considered new if it's nonzero.
1318 force_retrieval = !peek_capable && (ctl->errcount > 0);
1321 * Don't trust the message count passed by the server.
1322 * Without this check, it might be possible to do a
1323 * DNS-spoofing attack that would pass back a ridiculous
1324 * count, and allocate a malloc area that would overlap
1325 * a portion of the stack.
1327 if (count > INT_MAX/sizeof(int))
1329 report(stderr, GT_("bogus message count!"));
1330 return(PS_PROTOCOL);
1333 /* OK, we're going to gather size info next */
1334 xalloca(msgsizes, int *, sizeof(int) * count);
1335 xalloca(msgcodes, int *, sizeof(int) * count);
1336 for (i = 0; i < count; i++)
1337 msgcodes[i] = MSGLEN_UNKNOWN;
1340 * We need the size of each message before it's
1341 * loaded in order to pass it to the ESMTP SIZE
1342 * option. If the protocol has a getsizes method,
1343 * we presume this means it doesn't get reliable
1344 * sizes from message fetch responses.
1346 if (proto->getsizes)
1348 stage = STAGE_GETSIZES;
1349 err = (proto->getsizes)(mailserver_socket, count, msgsizes);
1356 for (i = 0; i < count; i++)
1357 bytes += msgsizes[i];
1361 /* mark some messages not to be retrieved */
1362 for (num = 1; num <= count; num++)
1364 if (NUM_NONZERO(ctl->limit) && (msgsizes[num-1] > ctl->limit))
1365 msgcodes[num-1] = MSGLEN_TOOLARGE;
1366 else if (ctl->fetchall || force_retrieval)
1368 else if (ctl->server.base_protocol->is_old && (ctl->server.base_protocol->is_old)(mailserver_socket,ctl,num))
1369 msgcodes[num-1] = MSGLEN_OLD;
1370 /* else if (msgsizes[num-1] == 512)
1371 msgcodes[num-1] = MSGLEN_OLD; (hmh) sample code to skip message */
1374 /* read, forward, and delete messages */
1375 stage = STAGE_FETCH;
1377 /* fetch in lockstep mode */
1378 err = fetch_messages(mailserver_socket, ctl,
1379 count, msgsizes, msgcodes,
1381 &fetches, &dispatches, &deletions);
1385 if (!check_only && ctl->skipped
1386 && run.poll_interval > 0 && !nodetach)
1388 clean_skipped_list(&ctl->skipped);
1389 send_size_warnings(ctl);
1394 * Only re-poll if we either had some actual forwards and
1395 * either allowed deletions and had no errors.
1396 * Otherwise it is far too easy to get into infinite loops.
1398 (dispatches && ctl->server.base_protocol->retry && !ctl->keep && !ctl->errcount);
1402 /* ordinary termination with no errors -- officially log out */
1403 err = (ctl->server.base_protocol->logout_cmd)(mailserver_socket, ctl);
1405 * Hmmmm...arguably this would be incorrect if we had fetches but
1406 * no dispatches (due to oversized messages, etc.)
1409 err = (fetches > 0) ? PS_SUCCESS : PS_NOMAIL;
1410 cleanupSockClose(mailserver_socket);
1414 /* we only get here on error */
1415 if (err != 0 && err != PS_SOCKET)
1417 stage = STAGE_LOGOUT;
1418 (ctl->server.base_protocol->logout_cmd)(mailserver_socket, ctl);
1420 cleanupSockClose(mailserver_socket);
1423 msg = (const char *)NULL; /* sacrifice to -Wall */
1427 msg = GT_("socket");
1430 msg = GT_("missing or bad RFC822 header");
1436 msg = GT_("client/server synchronization");
1439 msg = GT_("client/server protocol");
1442 msg = GT_("lock busy on server");
1445 msg = GT_("SMTP transaction");
1448 msg = GT_("DNS lookup");
1451 report(stderr, GT_("undefined error\n"));
1454 /* no report on PS_MAXFETCH or PS_UNDEFINED or PS_AUTHFAIL */
1455 if (err==PS_SOCKET || err==PS_SYNTAX
1456 || err==PS_IOERR || err==PS_ERROR || err==PS_PROTOCOL
1457 || err==PS_LOCKBUSY || err==PS_SMTP || err==PS_DNS)
1461 if (phase == FORWARDING_WAIT || phase == LISTENER_WAIT)
1462 stem = GT_("%s error while delivering to SMTP host %s\n");
1464 stem = GT_("%s error while fetching from %s\n");
1465 report(stderr, stem, msg, ctl->server.pollname);
1469 /* execute wrapup command, if any */
1470 if (ctl->postconnect && (err = system(ctl->postconnect)))
1472 report(stderr, GT_("post-connection command failed with status %d\n"), err);
1473 if (err == PS_SUCCESS)
1477 signal(SIGALRM, alrmsave);
1478 signal(SIGPIPE, pipesave);
1482 int do_protocol(ctl, proto)
1483 /* retrieve messages from server using given protocol method table */
1484 struct query *ctl; /* parsed options with merged-in defaults */
1485 const struct method *proto; /* protocol method table */
1490 if (ctl->server.authenticate == A_KERBEROS_V4)
1492 report(stderr, GT_("Kerberos V4 support not linked.\n"));
1495 #endif /* KERBEROS_V4 */
1498 if (ctl->server.authenticate == A_KERBEROS_V5)
1500 report(stderr, GT_("Kerberos V5 support not linked.\n"));
1503 #endif /* KERBEROS_V5 */
1505 /* lacking methods, there are some options that may fail */
1508 /* check for unsupported options */
1511 GT_("Option --flush is not supported with %s\n"),
1515 else if (ctl->fetchall) {
1517 GT_("Option --all is not supported with %s\n"),
1522 if (!proto->getsizes && NUM_SPECIFIED(ctl->limit))
1525 GT_("Option --limit is not supported with %s\n"),
1531 * If no expunge limit or we do expunges within the driver,
1532 * then just do one session, passing in any fetchlimit.
1534 if (proto->retry || !NUM_SPECIFIED(ctl->expunge))
1535 return(do_session(ctl, proto, NUM_VALUE_OUT(ctl->fetchlimit)));
1537 * There's an expunge limit, and it isn't handled in the driver itself.
1538 * OK; do multiple sessions, each fetching a limited # of messages.
1539 * Stop if the total count of retrieved messages exceeds ctl->fetchlimit
1540 * (if it was nonzero).
1546 int expunge = NUM_VALUE_OUT(ctl->expunge);
1547 int fetchlimit = NUM_VALUE_OUT(ctl->fetchlimit);
1550 if (fetchlimit > 0 && (expunge == 0 || expunge > fetchlimit - totalcount))
1551 expunge = fetchlimit - totalcount;
1552 err = do_session(ctl, proto, expunge);
1553 totalcount += expunge;
1554 if (NUM_SPECIFIED(ctl->fetchlimit) && totalcount >= fetchlimit)
1556 if (err != PS_LOCKBUSY)
1558 else if (lockouts >= MAX_LOCKOUTS)
1560 else /* err == PS_LOCKBUSY */
1563 * Allow time for the server lock to release. if we
1564 * don't do this, we'll often hit a locked-mailbox
1565 * condition and fail.
1571 (err == PS_MAXFETCH || err == PS_LOCKBUSY);
1578 /* driver.c ends here */