2 * imap.c -- IMAP2bis/IMAP4 protocol methods
4 * Copyright 1997 by Eric S. Raymond
5 * For license terms, see the file COPYING in this directory.
13 #if defined(STDC_HEADERS)
18 #include "fetchmail.h"
23 /* imap_version values */
24 #define IMAP2 -1 /* IMAP2 or IMAP2BIS, RFC1176 */
25 #define IMAP4 0 /* IMAP4 rev 0, RFC1730 */
26 #define IMAP4rev1 1 /* IMAP4 rev 1, RFC2060 */
28 /* global variables: please reinitialize them explicitly for proper
29 * working in daemon mode */
31 /* TODO: session variables to be initialized before server greeting */
32 static int preauth = FALSE;
34 /* session variables initialized in capa_probe() or imap_getauth() */
35 static char capabilities[MSGBUFSIZE+1];
36 static int imap_version = IMAP4;
37 static flag do_idle = FALSE, has_idle = FALSE;
38 static int expunge_period = 1;
40 /* mailbox variables initialized in imap_getrange() */
41 static int count = 0, oldcount = 0, recentcount = 0, unseen = 0, deletions = 0;
42 static unsigned int startcount = 1;
43 static int expunged = 0;
44 static unsigned int *unseen_messages;
46 /* for "IMAP> EXPUNGE" */
47 static int actual_deletions = 0;
49 /* for "IMAP> IDLE" */
50 static int saved_timeout = 0, idle_timeout = 0;
51 static time_t idle_start_time = 0;
53 static int imap_untagged_response(int sock, const char *buf)
54 /* interpret untagged status responses */
56 /* For each individual check, use a BLANK before the word to avoid
57 * confusion with the \Recent flag or similar */
58 if (stage == STAGE_GETAUTH
59 && !strncmp(buf, "* CAPABILITY", 12))
61 strlcpy(capabilities, buf + 12, sizeof(capabilities));
63 else if (stage == STAGE_GETAUTH
64 && !strncmp(buf, "* PREAUTH", 9))
68 else if (stage != STAGE_LOGOUT
69 && !strncmp(buf, "* BYE", 5))
71 /* log the unexpected bye from server as we expect the
72 * connection to be cut-off after this */
73 if (outlevel > O_SILENT)
74 report(stderr, GT_("Received BYE response from IMAP server: %s"), buf + 5);
76 else if (strstr(buf, " EXISTS"))
78 char *t; unsigned long u;
80 u = strtoul(buf+2, &t, 10);
82 * Don't trust the message count passed by the server.
83 * Without this check, it might be possible to do a
84 * DNS-spoofing attack that would pass back a ridiculous
85 * count, and allocate a malloc area that would overlap
86 * a portion of the stack.
88 if (errno /* strtoul failed */
89 || t == buf+2 /* no valid data */
90 || u > (unsigned long)(INT_MAX/sizeof(int)) /* too large */)
92 report(stderr, GT_("bogus message count in \"%s\"!"), buf);
95 count = u; /* safe as long as count <= INT_MAX - checked above */
97 if ((recentcount = count - oldcount) < 0)
101 * Nasty kluge to handle RFC2177 IDLE. If we know we're idling
102 * we can't wait for the tag matching the IDLE; we have to tell the
103 * server the IDLE is finished by shipping back a DONE when we
104 * see an EXISTS. Only after that will a tagged response be
105 * shipped. The idling flag also gets cleared on a timeout.
107 if (stage == STAGE_IDLE)
109 /* If IDLE isn't supported, we were only sending NOOPs anyway. */
112 /* we do our own write and report here to disable tagging */
113 SockWrite(sock, "DONE\r\n", 6);
114 if (outlevel >= O_MONITOR)
115 report(stdout, "IMAP> DONE\n");
118 mytimeout = saved_timeout;
119 stage = STAGE_GETRANGE;
122 /* we now compute recentcount as a difference between
123 * new and old EXISTS, hence disable RECENT check */
125 else if (strstr(buf, " RECENT"))
127 /* fixme: use strto[u]l and error checking */
128 recentcount = atoi(buf+2);
131 else if (strstr(buf, " EXPUNGE"))
133 unsigned long u; char *t;
134 /* the response "* 10 EXPUNGE" means that the currently
135 * tenth (i.e. only one) message has been deleted */
137 u = strtoul(buf+2, &t, 10);
138 if (errno /* conversion error */ || t == buf+2 /* no number found */) {
139 report(stderr, GT_("bogus EXPUNGE count in \"%s\"!"), buf);
148 /* We do expect an EXISTS response immediately
149 * after this, so this updation of recentcount is
150 * just a precaution! */
151 if ((recentcount = count - oldcount) < 0)
157 * The server may decide to make the mailbox read-only,
158 * which causes fetchmail to go into a endless loop
159 * fetching the same message over and over again.
161 * However, for check_only, we use EXAMINE which will
162 * mark the mailbox read-only as per the RFC.
164 * This checks for the condition and aborts if
165 * the mailbox is read-only.
167 * See RFC 2060 section 6.3.1 (SELECT).
168 * See RFC 2060 section 6.3.2 (EXAMINE).
170 else if (stage == STAGE_GETRANGE
171 && !check_only && strstr(buf, "[READ-ONLY]"))
182 static int imap_response(int sock, char *argbuf, struct RecvSplit *rs)
183 /* parse command response */
185 char buf[MSGBUFSIZE+1];
192 ok = gen_recv_split(sock, buf, sizeof(buf), rs);
194 ok = gen_recv(sock, buf, sizeof(buf));
195 if (ok != PS_SUCCESS)
198 /* all tokens in responses are caseblind */
199 for (cp = buf; *cp; cp++)
200 if (islower((unsigned char)*cp))
201 *cp = toupper((unsigned char)*cp);
203 /* untagged responses start with "* " */
204 if (buf[0] == '*' && buf[1] == ' ') {
205 ok = imap_untagged_response(sock, buf);
206 if (ok == PS_UNTAGGED)
208 if (argbuf && stage != STAGE_IDLE && tag[0] != '\0')
210 /* if there is an unmatched response, pass it back to
211 * the calling function for further analysis. The
212 * calling function should call imap_response() again
213 * to read the remaining response */
218 else if (ok != PS_SUCCESS)
222 if (stage == STAGE_IDLE)
224 /* reduce the timeout: servers may not reset their timeout
225 * when they send some information asynchronously */
226 mytimeout = idle_timeout - (time((time_t *) NULL) - idle_start_time);
228 return(PS_IDLETIMEOUT);
231 (tag[0] != '\0' && strncmp(buf, tag, strlen(tag)));
244 for (cp = buf; !isspace((unsigned char)*cp); cp++)
246 while (isspace((unsigned char)*cp))
249 if (strncasecmp(cp, "OK", 2) == 0)
255 else if (strncasecmp(cp, "BAD", 3) == 0)
257 else if (strncasecmp(cp, "NO", 2) == 0)
259 if (stage == STAGE_GETAUTH)
260 return(PS_AUTHFAIL); /* RFC2060, 6.2.2 */
261 else if (stage == STAGE_GETSIZES)
262 return(PS_SUCCESS); /* see comments in imap_getpartialsizes() */
271 static int imap_ok(int sock, char *argbuf)
272 /* parse command response */
276 while ((ok = imap_response(sock, argbuf, NULL)) == PS_UNTAGGED)
277 ; /* wait for the tagged response */
285 * NTLM support by Grant Edwards.
287 * Handle MS-Exchange NTLM authentication method. This is the same
288 * as the NTLM auth used by Samba for SMB related services. We just
289 * encode the packets in base64 instead of sending them out via a
292 * Much source (ntlm.h, smb*.c smb*.h) was borrowed from Samba.
295 static int do_imap_ntlm(int sock, struct query *ctl)
299 gen_send(sock, "AUTHENTICATE NTLM");
301 if ((result = ntlm_helper(sock, ctl, "IMAP")))
304 result = imap_ok (sock, NULL);
305 if (result == PS_SUCCESS)
312 static void imap_canonicalize(char *result, char *raw, size_t maxlen)
313 /* encode an IMAP password as per RFC1730's quoting conventions */
318 for (i = 0; i < strlen(raw) && i < maxlen; i++)
320 if ((raw[i] == '\\') || (raw[i] == '"'))
322 result[j++] = raw[i];
327 static int capa_probe(int sock, struct query *ctl)
328 /* set capability variables from a CAPA probe */
332 /* probe to see if we're running IMAP4 and can use RFC822.PEEK */
333 capabilities[0] = '\0';
334 if ((ok = gen_transact(sock, "CAPABILITY")) == PS_SUCCESS)
338 /* capability checks are supposed to be caseblind */
339 for (cp = capabilities; *cp; cp++)
340 *cp = toupper((unsigned char)*cp);
342 /* UW-IMAP server 10.173 notifies in all caps, but RFC2060 says we
343 should expect a response in mixed-case */
344 if (strstr(capabilities, "IMAP4REV1"))
346 imap_version = IMAP4rev1;
347 if (outlevel >= O_DEBUG)
348 report(stdout, GT_("Protocol identified as IMAP4 rev 1\n"));
352 imap_version = IMAP4;
353 if (outlevel >= O_DEBUG)
354 report(stdout, GT_("Protocol identified as IMAP4 rev 0\n"));
357 else if (ok == PS_ERROR)
359 imap_version = IMAP2;
360 if (outlevel >= O_DEBUG)
361 report(stdout, GT_("Protocol identified as IMAP2 or IMAP2BIS\n"));
367 * Handle idling. We depend on coming through here on startup
368 * and after each timeout (including timeouts during idles).
373 if (strstr(capabilities, "IDLE"))
377 if (outlevel >= O_VERBOSE)
378 report(stdout, GT_("will idle after poll\n"));
381 peek_capable = (imap_version >= IMAP4);
386 static int do_authcert (int sock, const char *command, const char *name)
387 /* do authentication "external" (authentication provided by client cert) */
393 size_t len = strlen(name);
394 if ((len / 3) + ((len % 3) ? 4 : 0) < sizeof(buf))
395 to64frombits (buf, name, strlen(name));
397 return PS_AUTHFAIL; /* buffer too small. */
401 return gen_transact(sock, "%s EXTERNAL %s",command,buf);
404 static int imap_getauth(int sock, struct query *ctl, char *greeting)
405 /* apply for connection authorization */
411 * Assumption: expunges are cheap, so we want to do them
412 * after every message unless user said otherwise.
414 if (NUM_SPECIFIED(ctl->expunge))
415 expunge_period = NUM_VALUE_OUT(ctl->expunge);
419 if ((ok = capa_probe(sock, ctl)))
423 * If either (a) we saw a PREAUTH token in the greeting, or
424 * (b) the user specified ssh preauthentication, then we're done.
426 if (preauth || ctl->server.authenticate == A_SSH)
428 preauth = FALSE; /* reset for the next session */
433 if (maybe_tls(ctl)) {
436 commonname = ctl->server.pollname;
438 commonname = ctl->server.via;
439 if (ctl->sslcommonname)
440 commonname = ctl->sslcommonname;
442 if (strstr(capabilities, "STARTTLS")
443 || must_tls(ctl)) /* if TLS is mandatory, ignore capabilities */
445 /* Use "tls1" rather than ctl->sslproto because tls1 is the only
446 * protocol that will work with STARTTLS. Don't need to worry
447 * whether TLS is mandatory or opportunistic unless SSLOpen() fails
449 if (gen_transact(sock, "STARTTLS") == PS_SUCCESS
450 && SSLOpen(sock, ctl->sslcert, ctl->sslkey, "tls1", ctl->sslcertck,
451 ctl->sslcertfile, ctl->sslcertpath, ctl->sslfingerprint, commonname,
452 ctl->server.pollname, &ctl->remotename) != -1)
455 * RFC 2595 says this:
457 * "Once TLS has been started, the client MUST discard cached
458 * information about server capabilities and SHOULD re-issue the
459 * CAPABILITY command. This is necessary to protect against
460 * man-in-the-middle attacks which alter the capabilities list prior
461 * to STARTTLS. The server MAY advertise different capabilities
464 * Now that we're confident in our TLS connection we can
465 * guarantee a secure capability re-probe.
467 if ((ok = capa_probe(sock, ctl)))
469 if (outlevel >= O_VERBOSE)
471 report(stdout, GT_("%s: upgrade to TLS succeeded.\n"), commonname);
473 } else if (must_tls(ctl)) {
474 /* Config required TLS but we couldn't guarantee it, so we must
476 report(stderr, GT_("%s: upgrade to TLS failed.\n"), commonname);
479 if (outlevel >= O_VERBOSE) {
480 report(stdout, GT_("%s: opportunistic upgrade to TLS failed, trying to continue\n"), commonname);
482 /* We don't know whether the connection is in a working state, so
483 * test by issuing a NOOP. */
484 if (gen_transact(sock, "NOOP") != PS_SUCCESS) {
485 /* Not usable. Empty sslproto to force an unencrypted
486 * connection on the next attempt, and repoll. */
487 ctl->sslproto = xstrdup("");
490 /* Usable. Proceed with authenticating insecurely. */
494 #endif /* SSL_ENABLE */
497 * Time to authenticate the user.
498 * Try the protocol variants that don't require passwords first.
502 /* Yahoo hack - we'll just try ID if it was offered by the server,
503 * and IGNORE errors. */
505 char *tmp = strstr(capabilities, " ID");
506 if (tmp && !isalnum((unsigned char)tmp[3]) && strstr(ctl->server.via ? ctl->server.via : ctl->server.pollname, "yahoo.com")) {
507 (void)gen_transact(sock, "ID (\"guid\" \"1\")");
511 if ((ctl->server.authenticate == A_ANY
512 || ctl->server.authenticate == A_EXTERNAL)
513 && strstr(capabilities, "AUTH=EXTERNAL"))
515 ok = do_authcert(sock, "AUTHENTICATE", ctl->remotename);
518 /* SASL cancellation of authentication */
520 if (ctl->server.authenticate != A_ANY)
528 if (((ctl->server.authenticate == A_ANY && check_gss_creds("imap", ctl->server.truename) == PS_SUCCESS)
529 || ctl->server.authenticate == A_GSSAPI)
530 && strstr(capabilities, "AUTH=GSSAPI"))
532 if ((ok = do_gssauth(sock, "AUTHENTICATE", "imap",
533 ctl->server.truename, ctl->remotename)))
535 if (ctl->server.authenticate != A_ANY)
544 if ((ctl->server.authenticate == A_ANY
545 || ctl->server.authenticate == A_KERBEROS_V4
546 || ctl->server.authenticate == A_KERBEROS_V5)
547 && strstr(capabilities, "AUTH=KERBEROS_V4"))
549 if ((ok = do_rfc1731(sock, "AUTHENTICATE", ctl->server.truename)))
551 /* SASL cancellation of authentication */
553 if(ctl->server.authenticate != A_ANY)
559 #endif /* KERBEROS_V4 */
562 * No such luck. OK, now try the variants that mask your password
563 * in a challenge-response.
566 if ((ctl->server.authenticate == A_ANY && strstr(capabilities, "AUTH=CRAM-MD5"))
567 || ctl->server.authenticate == A_CRAM_MD5)
569 if ((ok = do_cram_md5 (sock, "AUTHENTICATE", ctl, NULL)))
571 if(ctl->server.authenticate != A_ANY)
579 if ((ctl->server.authenticate == A_ANY
580 || ctl->server.authenticate == A_OTP)
581 && strstr(capabilities, "AUTH=X-OTP")) {
582 if ((ok = do_otp(sock, "AUTHENTICATE", ctl)))
584 /* SASL cancellation of authentication */
586 if(ctl->server.authenticate != A_ANY)
593 if (ctl->server.authenticate == A_OTP)
596 GT_("Required OTP capability not compiled into fetchmail\n"));
598 #endif /* OPIE_ENABLE */
601 if ((ctl->server.authenticate == A_ANY
602 || ctl->server.authenticate == A_NTLM)
603 && strstr (capabilities, "AUTH=NTLM")) {
604 if ((ok = do_imap_ntlm(sock, ctl)))
606 if(ctl->server.authenticate != A_ANY)
613 if (ctl->server.authenticate == A_NTLM)
616 GT_("Required NTLM capability not compiled into fetchmail\n"));
618 #endif /* NTLM_ENABLE */
620 #ifdef __UNUSED__ /* The Cyrus IMAP4rev1 server chokes on this */
621 /* this handles either AUTH=LOGIN or AUTH-LOGIN */
622 if ((imap_version >= IMAP4rev1) && (!strstr(capabilities, "LOGIN")))
625 GT_("Required LOGIN capability not supported by server\n"));
627 #endif /* __UNUSED__ */
630 * We're stuck with sending the password en clair.
631 * The reason for this odd-looking logic is that some
632 * servers return LOGINDISABLED even though login
633 * actually works. So arrange things in such a way that
634 * setting auth passwd makes it ignore this capability.
636 if((ctl->server.authenticate==A_ANY&&!strstr(capabilities,"LOGINDISABLED"))
637 || ctl->server.authenticate == A_PASSWORD)
639 /* these sizes guarantee no buffer overflow */
640 char *remotename, *password;
642 rnl = 2 * strlen(ctl->remotename) + 1;
643 pwl = 2 * strlen(ctl->password) + 1;
644 remotename = (char *)xmalloc(rnl);
645 password = (char *)xmalloc(pwl);
647 imap_canonicalize(remotename, ctl->remotename, rnl);
648 imap_canonicalize(password, ctl->password, pwl);
650 snprintf(shroud, sizeof (shroud), "\"%s\"", password);
651 ok = gen_transact(sock, "LOGIN \"%s\" \"%s\"", remotename, password);
652 memset(shroud, 0x55, sizeof(shroud));
654 memset(password, 0x55, strlen(password));
659 if(ctl->server.authenticate != A_ANY)
669 static int internal_expunge(int sock)
670 /* ship an expunge, resetting associated counters */
674 actual_deletions = 0;
676 if ((ok = gen_transact(sock, "EXPUNGE")))
679 /* if there is a mismatch between the number of mails which should
680 * have been expunged and the number of mails actually expunged,
681 * another email client may be deleting mails. Quit here,
682 * otherwise fetchmail gets out-of-sync with the imap server,
683 * reports the wrong size to the SMTP server on MAIL FROM: and
684 * triggers a "message ... was not the expected length" error on
685 * every subsequent mail */
686 if (deletions > 0 && deletions != actual_deletions)
689 GT_("mail expunge mismatch (%d actual != %d expected)\n"),
690 actual_deletions, deletions);
695 expunged += deletions;
698 #ifdef IMAP_UID /* not used */
700 #endif /* IMAP_UID */
705 static int imap_idle(int sock)
706 /* start an RFC2177 IDLE, or fake one if unsupported */
710 saved_timeout = mytimeout;
713 /* special timeout to terminate the IDLE and re-issue it
714 * at least every 28 minutes:
715 * (the server may have an inactivity timeout) */
716 mytimeout = idle_timeout = 1680; /* 28 min */
717 time(&idle_start_time);
719 /* enter IDLE mode */
720 ok = gen_transact(sock, "IDLE");
722 if (ok == PS_IDLETIMEOUT) {
723 /* send "DONE" continuation */
724 SockWrite(sock, "DONE\r\n", 6);
725 if (outlevel >= O_MONITOR)
726 report(stdout, "IMAP> DONE\n");
727 /* reset stage and timeout here: we are not idling any more */
728 mytimeout = saved_timeout;
729 stage = STAGE_GETRANGE;
730 /* get OK IDLE message */
731 ok = imap_ok(sock, NULL);
733 } else { /* no idle support, fake it */
734 /* Note: stage and timeout have not been changed here as NOOP
736 ok = gen_transact(sock, "NOOP");
738 /* no error, but no new mail either */
739 if (ok == PS_SUCCESS && recentcount == 0)
741 /* There are some servers who do send new mail
742 * notification out of the blue. This is in compliance
743 * with RFC 2060 section 5.3. Wait for that with a low
745 mytimeout = idle_timeout = 28;
746 time(&idle_start_time);
748 /* We are waiting for notification; no tag needed */
750 /* wait (briefly) for an unsolicited status update */
751 ok = imap_ok(sock, NULL);
752 if (ok == PS_IDLETIMEOUT) {
753 /* no notification came; ok */
759 /* restore normal timeout value */
761 mytimeout = saved_timeout;
762 stage = STAGE_GETRANGE;
767 static int imap_search(int sock, struct query *ctl, int count)
768 /* search for unseen messages */
771 char buf[MSGBUFSIZE+1], *cp;
773 /* Don't count deleted messages. Enabled only for IMAP4 servers or
774 * higher and only when keeping mails. This flag will have an
775 * effect only when user has marked some unread mails for deletion
776 * using another e-mail client. */
777 flag skipdeleted = (imap_version >= IMAP4) && ctl->keep;
778 const char *undeleted;
780 /* structure to keep the end portion of the incomplete response */
783 /* startcount is higher than count so that if there are no
784 * unseen messages, imap_getsizes() will not need to do
786 startcount = count + 1;
790 undeleted = (skipdeleted ? " UNDELETED" : "");
791 gen_send(sock, "SEARCH UNSEEN%s", undeleted);
792 gen_recv_split_init("* SEARCH", &rs);
793 while ((ok = imap_response(sock, buf, &rs)) == PS_UNTAGGED)
795 if ((cp = strstr(buf, "* SEARCH")))
799 cp += 8; /* skip "* SEARCH" */
800 while (*cp && unseen < count)
802 /* skip whitespace */
803 while (*cp && isspace((unsigned char)*cp))
810 um = strtoul(cp,&ep,10);
811 if (errno == 0 && ep > cp
812 && um <= INT_MAX && um <= (unsigned)count)
814 unseen_messages[unseen++] = um;
815 if (outlevel >= O_DEBUG)
816 report(stdout, GT_("%lu is unseen\n"), um);
825 if (ok != PS_ERROR) /* success or non-protocol error */
828 /* there is a protocol error. try a different search command. */
831 /* retry with "SEARCH UNSEEN" */
835 /* try with "FETCH 1:n FLAGS" */
840 gen_send(sock, "FETCH %d FLAGS", count);
842 gen_send(sock, "FETCH %d:%d FLAGS", 1, count);
843 while ((ok = imap_response(sock, buf, NULL)) == PS_UNTAGGED)
848 /* expected response format:
849 * IMAP< * 1 FETCH (FLAGS (\Seen))
850 * IMAP< * 2 FETCH (FLAGS (\Seen \Deleted))
851 * IMAP< * 3 FETCH (FLAGS ())
852 * IMAP< * 4 FETCH (FLAGS (\Recent))
853 * IMAP< * 5 FETCH (UID 10 FLAGS (\Recent))
856 && sscanf(buf, "* %u %n", &num, &consumed) == 1
857 && 0 == strncasecmp(buf+consumed, "FETCH", 5)
858 && isspace((unsigned char)buf[consumed+5])
859 && num >= 1 && num <= (unsigned)count
860 && strstr(buf, "FLAGS ")
861 && !strstr(buf, "\\SEEN")
862 && !strstr(buf, "\\DELETED"))
864 unseen_messages[unseen++] = num;
865 if (outlevel >= O_DEBUG)
866 report(stdout, GT_("%u is unseen\n"), num);
867 if (startcount > num)
874 static int imap_getrange(int sock,
877 int *countp, int *newp, int *bytes)
878 /* get range of messages to be fetched */
882 /* find out how many messages are waiting */
887 /* deleted mails have already been expunged by
888 * end_mailbox_poll().
890 * recentcount is already set here by the last imap command which
891 * returned EXISTS on detecting new mail. if recentcount is 0, wait
894 * this is a while loop because imap_idle() might return on other
895 * mailbox changes also */
896 while (recentcount == 0 && do_idle) {
898 ok = imap_idle(sock);
901 report(stderr, GT_("re-poll failed\n"));
905 /* if recentcount is 0, return no mail */
906 if (recentcount == 0)
908 if (outlevel >= O_DEBUG)
909 report(stdout, ngettext("%d message waiting after re-poll\n",
910 "%d messages waiting after re-poll\n",
915 oldcount = count = 0;
916 ok = gen_transact(sock,
917 check_only ? "EXAMINE \"%s\"" : "SELECT \"%s\"",
918 folder ? folder : "INBOX");
919 /* imap_ok returns PS_LOCKBUSY for READ-ONLY folders,
920 * which we can safely use in fetchall keep only */
921 if (ok == PS_LOCKBUSY && ctl->fetchall && ctl-> keep)
926 report(stderr, GT_("mailbox selection failed\n"));
929 else if (outlevel >= O_DEBUG)
930 report(stdout, ngettext("%d message waiting after first poll\n",
931 "%d messages waiting after first poll\n",
935 * We should have an expunge here to
936 * a) avoid fetching deleted mails during 'fetchall'
937 * b) getting a wrong count of mails during 'no fetchall'
939 if (!check_only && !ctl->keep && count > 0)
941 ok = internal_expunge(sock);
944 report(stderr, GT_("expunge failed\n"));
947 if (outlevel >= O_DEBUG)
948 report(stdout, ngettext("%d message waiting after expunge\n",
949 "%d messages waiting after expunge\n",
953 if (count == 0 && do_idle)
955 /* no messages? then we may need to idle until we get some */
957 ok = imap_idle(sock);
960 report(stderr, GT_("re-poll failed\n"));
964 if (outlevel >= O_DEBUG)
965 report(stdout, ngettext("%d message waiting after re-poll\n",
966 "%d messages waiting after re-poll\n",
971 *countp = oldcount = count;
975 /* OK, now get a count of unseen messages and their indices */
976 if (!ctl->fetchall && count > 0)
979 free(unseen_messages);
980 unseen_messages = (unsigned int *)xmalloc(count * sizeof(unsigned int));
981 memset(unseen_messages, 0, count * sizeof(unsigned int));
984 ok = imap_search(sock, ctl, count);
987 report(stderr, GT_("search for unseen messages failed\n"));
991 if (outlevel >= O_DEBUG && unseen > 0)
992 report(stdout, GT_("%u is first unseen\n"), startcount);
1003 static int imap_getpartialsizes(int sock, int first, int last, int *sizes)
1004 /* capture the sizes of messages #first-#last */
1006 char buf [MSGBUFSIZE+1];
1010 * Some servers (as in, PMDF5.1-9.1 under OpenVMS 6.1)
1011 * won't accept 1:1 as valid set syntax. Some implementors
1012 * should be taken out and shot for excessive anality.
1014 * Microsoft Exchange (brain-dead piece of crap that it is)
1015 * sometimes gets its knickers in a knot about bodiless messages.
1016 * You may see responses like this:
1018 * fetchmail: IMAP> A0004 FETCH 1:9 RFC822.SIZE
1019 * fetchmail: IMAP< * 2 FETCH (RFC822.SIZE 1187)
1020 * fetchmail: IMAP< * 3 FETCH (RFC822.SIZE 3954)
1021 * fetchmail: IMAP< * 4 FETCH (RFC822.SIZE 1944)
1022 * fetchmail: IMAP< * 5 FETCH (RFC822.SIZE 2933)
1023 * fetchmail: IMAP< * 6 FETCH (RFC822.SIZE 1854)
1024 * fetchmail: IMAP< * 7 FETCH (RFC822.SIZE 34054)
1025 * fetchmail: IMAP< * 8 FETCH (RFC822.SIZE 5561)
1026 * fetchmail: IMAP< * 9 FETCH (RFC822.SIZE 1101)
1027 * fetchmail: IMAP< A0004 NO The requested item could not be found.
1029 * This means message 1 has only headers. For kicks and grins
1030 * you can telnet in and look:
1032 * A003 NO The requested item could not be found.
1033 * A004 fetch 1 rfc822.header
1034 * A004 NO The requested item could not be found.
1036 * * 1 FETCH (BODY ("TEXT" "PLAIN" ("CHARSET" "US-ASCII") NIL NIL "7BIT" 35 3))
1037 * A006 OK FETCH completed.
1039 * To get around this, we treat the final NO as success and count
1040 * on the fact that the sizes array has been preinitialized with a
1041 * known-bad size value.
1044 /* expunges change the fetch numbers */
1049 gen_send(sock, "FETCH %d RFC822.SIZE", last);
1050 else if (last > first)
1051 gen_send(sock, "FETCH %d:%d RFC822.SIZE", first, last);
1052 else /* no unseen messages! */
1054 while ((ok = imap_response(sock, buf, NULL)) == PS_UNTAGGED)
1061 /* expected response formats:
1062 * IMAP> A0005 FETCH 1 RFC822.SIZE
1063 * IMAP< * 1 FETCH (RFC822.SIZE 1187)
1064 * IMAP< * 1 FETCH (UID 16 RFC822.SIZE 1447)
1066 if (sscanf(buf, "* %d %n", &num, &consumed) == 1
1067 && 0 == strncasecmp(buf + consumed, "FETCH", 5)
1068 && isspace((unsigned char)buf[consumed + 5])
1069 && (ptr = strstr(buf, "RFC822.SIZE "))
1070 && sscanf(ptr, "RFC822.SIZE %u", &size) == 1)
1072 if (num >= first && num <= last)
1073 sizes[num - first] = size;
1076 GT_("Warning: ignoring bogus data for message sizes returned by the server.\n"));
1082 static int imap_getsizes(int sock, int count, int *sizes)
1083 /* capture the sizes of all messages */
1085 return imap_getpartialsizes(sock, 1, count, sizes);
1088 static int imap_is_old(int sock, struct query *ctl, int number)
1089 /* is the given message old? */
1097 * Expunges change the fetch numbers, but unseen_messages contains
1098 * indices from before any expungees were done. So neither the
1099 * argument nor the values in message_sequence need to be decremented.
1103 for (i = 0; i < unseen; i++)
1104 if (unseen_messages[i] == (unsigned)number)
1114 static char *skip_token(char *ptr)
1116 while(isspace((unsigned char)*ptr)) ptr++;
1117 while(!isspace((unsigned char)*ptr) && !iscntrl((unsigned char)*ptr)) ptr++;
1118 while(isspace((unsigned char)*ptr)) ptr++;
1123 static int imap_fetch_headers(int sock, struct query *ctl,int number,int *lenp)
1124 /* request headers of nth message */
1126 char buf [MSGBUFSIZE+1];
1132 /* expunges change the fetch numbers */
1136 * This is blessed by RFC1176, RFC1730, RFC2060.
1137 * According to the RFCs, it should *not* set the \Seen flag.
1139 gen_send(sock, "FETCH %d RFC822.HEADER", number);
1141 /* looking for FETCH response */
1142 if ((ok = imap_response(sock, buf, NULL)) == PS_UNTAGGED)
1145 /* expected response formats:
1146 * IMAP> A0006 FETCH 1 RFC822.HEADER
1147 * IMAP< * 1 FETCH (RFC822.HEADER {1360}
1148 * IMAP< * 1 FETCH (UID 16 RFC822.HEADER {1360}
1149 * IMAP< * 1 FETCH (UID 16 RFC822.SIZE 4029 RFC822.HEADER {1360}
1151 if (sscanf(buf, "* %d %n", &num, &consumed) == 1
1152 && 0 == strncasecmp(buf + consumed, "FETCH", 5)
1153 && isspace((unsigned char)buf[5+consumed])
1155 && (ptr = strstr(buf, "RFC822.HEADER"))
1156 && sscanf(ptr, "RFC822.HEADER {%d}%n", lenp, &consumed) == 1
1157 && ptr[consumed-1] == '}')
1162 /* wait for a tagged response */
1165 /* try to recover for some responses */
1166 if (!strncmp(buf, "* NO", 4) ||
1167 !strncmp(buf, "* BAD", 5))
1169 return(PS_TRANSIENT);
1172 /* a response which does not match any of the above */
1173 if (outlevel > O_SILENT)
1174 report(stderr, GT_("Incorrect FETCH response: %s.\n"), buf);
1177 else if (ok == PS_SUCCESS)
1179 /* an unexpected tagged response */
1180 if (outlevel > O_SILENT)
1181 report(stderr, GT_("Incorrect FETCH response: %s.\n"), buf);
1187 static int imap_fetch_body(int sock, struct query *ctl, int number, int *lenp)
1188 /* request body of nth message */
1190 char buf [MSGBUFSIZE+1], *cp;
1194 /* expunges change the fetch numbers */
1198 * If we're using IMAP4, we can fetch the message without setting its
1199 * seen flag. This is good! It means that if the protocol exchange
1200 * craps out during the message, it will still be marked `unseen' on
1203 * According to RFC2060, and Mark Crispin the IMAP maintainer,
1204 * FETCH %d BODY[TEXT] and RFC822.TEXT are "functionally
1205 * equivalent". However, we know of at least one server that
1206 * treats them differently in the presence of MIME attachments;
1207 * the latter form downloads the attachment, the former does not.
1208 * The server is InterChange, and the fool who implemented this
1209 * misfeature ought to be strung up by his thumbs.
1211 * When I tried working around this by disabling use of the 4rev1 form,
1212 * I found that doing this breaks operation with M$ Exchange.
1213 * Annoyingly enough, Exchange's refusal to cope is technically legal
1214 * under RFC2062. Trust Microsoft, the Great Enemy of interoperability
1215 * standards, to find a way to make standards compliance irritating....
1217 switch (imap_version)
1219 case IMAP4rev1: /* RFC 2060 */
1220 gen_send(sock, "FETCH %d BODY.PEEK[TEXT]", number);
1223 case IMAP4: /* RFC 1730 */
1224 gen_send(sock, "FETCH %d RFC822.TEXT.PEEK", number);
1227 default: /* RFC 1176 */
1228 gen_send(sock, "FETCH %d RFC822.TEXT", number);
1232 /* looking for FETCH response */
1236 if ((ok = gen_recv(sock, buf, sizeof(buf))))
1239 (!strstr(buf+4, "FETCH") || sscanf(buf+2, "%d", &num) != 1);
1244 /* Understand "NIL" as length => no body present
1245 * (MS Exchange, BerliOS Bug #11980) */
1246 if (strstr(buf+10, "NIL)")) {
1251 /* Understand the empty string. Seen on Yahoo. */
1252 /* XXX FIXME: we should be able to handle strings here. */
1253 if (strstr(buf+10, "\"\")")) {
1259 * Try to extract a length from the FETCH response. RFC2060 requires
1260 * it to be present, but at least one IMAP server (Novell GroupWise)
1261 * botches this. The overflow check is needed because of a broken
1262 * server called dbmail that returns huge garbage lengths.
1264 if ((cp = strchr(buf, '{'))) {
1268 l = strtol(cp, &t, 10);
1269 if (errno || t == cp || (t && !strchr(t, '}')) /* parse error */
1270 || l < 0 || l > INT_MAX /* range check */) {
1276 *lenp = -1; /* missing length part in FETCH reponse */
1282 static int imap_trail(int sock, struct query *ctl, const char *tag)
1283 /* discard tail of FETCH response after reading message text */
1285 /* expunges change the fetch numbers */
1286 /* number -= expunged; */
1291 return imap_ok(sock, NULL);
1294 static int imap_delete(int sock, struct query *ctl, int number)
1295 /* set delete flag for given message */
1298 /* Select which flags to set on message deletion: */
1299 const char delflags_seen[] = "\\Seen \\Deleted";
1300 const char delflags_unseen[] = "\\Deleted";
1301 static const char *delflags;
1302 /* Which environment variable to look for: */
1303 const char dis_env[] = "FETCHMAIL_IMAP_DELETED_REMAINS_UNSEEN";
1307 if ((tmp = getenv(dis_env)) != NULL && *tmp) {
1308 delflags = delflags_unseen;
1310 /* DEFAULT since many fetchmail versions <= 6.3.X */
1311 delflags = delflags_seen;
1316 /* expunges change the fetch numbers */
1320 * Use SILENT if possible as a minor throughput optimization.
1321 * Note: this has been dropped from IMAP4rev1.
1323 * We set \Seen because there are some IMAP servers (notably HP
1324 * OpenMail and MS Exchange) do message-receipt DSNs,
1325 * but only when the seen bit gets set.
1326 * This is the appropriate time -- we get here right
1327 * after the local SMTP response that says delivery was
1330 if ((ok = gen_transact(sock,
1331 imap_version == IMAP4
1332 ? "STORE %d +FLAGS.SILENT (%s)"
1333 : "STORE %d +FLAGS (%s)",
1340 * We do an expunge after expunge_period messages, rather than
1341 * just before quit, so that a line hit during a long session
1342 * won't result in lots of messages being fetched again during
1345 if (NUM_NONZERO(expunge_period) && (deletions % expunge_period) == 0)
1347 if ((ok = internal_expunge(sock)))
1354 static int imap_mark_seen(int sock, struct query *ctl, int number)
1355 /* mark the given message as seen */
1359 /* expunges change the message numbers */
1362 return(gen_transact(sock,
1363 imap_version == IMAP4
1364 ? "STORE %d +FLAGS.SILENT (\\Seen)"
1365 : "STORE %d +FLAGS (\\Seen)",
1369 static int imap_end_mailbox_poll(int sock, struct query *ctl)
1370 /* cleanup mailbox before we idle or switch to another one */
1374 internal_expunge(sock);
1378 static int imap_logout(int sock, struct query *ctl)
1379 /* send logout command */
1382 /* if any un-expunged deletions remain, ship an expunge now */
1384 internal_expunge(sock);
1387 /* Memory clean-up */
1388 if (unseen_messages)
1389 free(unseen_messages);
1390 #endif /* USE_SEARCH */
1392 return(gen_transact(sock, "LOGOUT"));
1395 static const struct method imap =
1397 "IMAP", /* Internet Message Access Protocol */
1398 "imap", /* service (plain and TLS) */
1399 "imaps", /* service (SSL) */
1400 TRUE, /* this is a tagged protocol */
1401 FALSE, /* no message delimiter */
1402 imap_ok, /* parse command response */
1403 imap_getauth, /* get authorization */
1404 imap_getrange, /* query range of messages */
1405 imap_getsizes, /* get sizes of messages (used for ESMTP SIZE option) */
1406 imap_getpartialsizes, /* get sizes of subset of messages (used for ESMTP SIZE option) */
1407 imap_is_old, /* no UID check */
1408 imap_fetch_headers, /* request given message headers */
1409 imap_fetch_body, /* request given message body */
1410 imap_trail, /* eat message trailer */
1411 imap_delete, /* delete the message */
1412 imap_mark_seen, /* how to mark a message as seen */
1413 imap_end_mailbox_poll, /* end-of-mailbox processing */
1414 imap_logout, /* expunge and exit */
1415 TRUE, /* yes, we can re-poll */
1418 int doIMAP(struct query *ctl)
1419 /* retrieve messages using IMAP Version 2bis or Version 4 */
1421 return(do_protocol(ctl, &imap));
1424 /* imap.c ends here */