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.
12 #if defined(STDC_HEADERS)
17 #include "fetchmail.h"
22 /* imap_version values */
23 #define IMAP2 -1 /* IMAP2 or IMAP2BIS, RFC1176 */
24 #define IMAP4 0 /* IMAP4 rev 0, RFC1730 */
25 #define IMAP4rev1 1 /* IMAP4 rev 1, RFC2060 */
27 static int count = 0, recentcount = 0, unseen = 0, deletions = 0;
28 static int recentcount_ok = 0;
29 static unsigned int startcount = 1;
30 static int expunged, expunge_period, saved_timeout = 0;
31 static int imap_version, preauth;
32 static flag do_idle, has_idle;
33 static char capabilities[MSGBUFSIZE+1];
34 static unsigned int *unseen_messages;
36 static int imap_ok(int sock, char *argbuf)
37 /* parse command response */
39 char buf[MSGBUFSIZE+1];
45 if ((ok = gen_recv(sock, buf, sizeof(buf))))
48 /* all tokens in responses are caseblind */
49 for (cp = buf; *cp; cp++)
50 if (islower((unsigned char)*cp))
51 *cp = toupper((unsigned char)*cp);
53 /* interpret untagged status responses */
54 if (strstr(buf, "* CAPABILITY"))
56 strlcpy(capabilities, buf + 12, sizeof(capabilities));
58 else if (strstr(buf, "EXISTS"))
62 * Don't trust the message count passed by the server.
63 * Without this check, it might be possible to do a
64 * DNS-spoofing attack that would pass back a ridiculous
65 * count, and allocate a malloc area that would overlap
66 * a portion of the stack.
68 if (count > INT_MAX/sizeof(int))
70 report(stderr, GT_("bogus message count!"));
75 * Nasty kluge to handle RFC2177 IDLE. If we know we're idling
76 * we can't wait for the tag matching the IDLE; we have to tell the
77 * server the IDLE is finished by shipping back a DONE when we
78 * see an EXISTS. Only after that will a tagged response be
79 * shipped. The idling flag also gets cleared on a timeout.
81 if (stage == STAGE_IDLE)
83 /* If IDLE isn't supported, we were only sending NOOPs anyway. */
86 /* we do our own write and report here to disable tagging */
87 SockWrite(sock, "DONE\r\n", 6);
88 if (outlevel >= O_MONITOR)
89 report(stdout, "IMAP> DONE\n");
92 mytimeout = saved_timeout;
96 /* a space is required to avoid confusion with the \Recent flag */
97 else if (strstr(buf, " RECENT"))
100 recentcount = atoi(buf+2);
102 else if (strstr(buf, "EXPUNGE") && !strstr(buf, "OK"))
104 /* the response "* 10 EXPUNGE" means that the currently
105 * tenth (i.e. only one) message has been deleted */
111 else if (strstr(buf, "PREAUTH"))
114 * The server may decide to make the mailbox read-only,
115 * which causes fetchmail to go into a endless loop
116 * fetching the same message over and over again.
118 * However, for check_only, we use EXAMINE which will
119 * mark the mailbox read-only as per the RFC.
121 * This checks for the condition and aborts if
122 * the mailbox is read-only.
124 * See RFC 2060 section 6.3.1 (SELECT).
125 * See RFC 2060 section 6.3.2 (EXAMINE).
127 else if (!check_only && strstr(buf, "[READ-ONLY]"))
130 (tag[0] != '\0' && strncmp(buf, tag, strlen(tag)));
143 for (cp = buf; !isspace((unsigned char)*cp); cp++)
145 while (isspace((unsigned char)*cp))
148 if (strncasecmp(cp, "OK", 2) == 0)
154 else if (strncasecmp(cp, "BAD", 3) == 0)
156 else if (strncasecmp(cp, "NO", 2) == 0)
158 if (stage == STAGE_GETAUTH)
159 return(PS_AUTHFAIL); /* RFC2060, 6.2.2 */
171 static tSmbNtlmAuthRequest request;
172 static tSmbNtlmAuthChallenge challenge;
173 static tSmbNtlmAuthResponse response;
176 * NTLM support by Grant Edwards.
178 * Handle MS-Exchange NTLM authentication method. This is the same
179 * as the NTLM auth used by Samba for SMB related services. We just
180 * encode the packets in base64 instead of sending them out via a
183 * Much source (ntlm.h, smb*.c smb*.h) was borrowed from Samba.
186 static int do_imap_ntlm(int sock, struct query *ctl)
191 gen_send(sock, "AUTHENTICATE NTLM");
193 if ((result = gen_recv(sock, msgbuf, sizeof msgbuf)))
196 if (msgbuf[0] != '+')
199 buildSmbNtlmAuthRequest(&request,ctl->remotename,NULL);
201 if (outlevel >= O_DEBUG)
202 dumpSmbNtlmAuthRequest(stdout, &request);
204 memset(msgbuf,0,sizeof msgbuf);
205 to64frombits (msgbuf, (unsigned char*)&request, SmbLength(&request));
207 if (outlevel >= O_MONITOR)
208 report(stdout, "IMAP> %s\n", msgbuf);
210 strcat(msgbuf,"\r\n");
211 SockWrite (sock, msgbuf, strlen (msgbuf));
213 if ((gen_recv(sock, msgbuf, sizeof msgbuf)))
216 len = from64tobits ((char*)&challenge, msgbuf, sizeof(challenge));
218 if (outlevel >= O_DEBUG)
219 dumpSmbNtlmAuthChallenge(stdout, &challenge);
221 buildSmbNtlmAuthResponse(&challenge, &response,ctl->remotename,ctl->password);
223 if (outlevel >= O_DEBUG)
224 dumpSmbNtlmAuthResponse(stdout, &response);
226 memset(msgbuf,0,sizeof msgbuf);
227 to64frombits (msgbuf, (unsigned char*)&response, SmbLength(&response));
229 if (outlevel >= O_MONITOR)
230 report(stdout, "IMAP> %s\n", msgbuf);
232 strcat(msgbuf,"\r\n");
233 SockWrite (sock, msgbuf, strlen (msgbuf));
235 if ((result = gen_recv (sock, msgbuf, sizeof msgbuf)))
238 if (strstr (msgbuf, "OK"))
245 static int imap_canonicalize(char *result, char *raw, int maxlen)
246 /* encode an IMAP password as per RFC1730's quoting conventions */
251 for (i = 0; i < strlen(raw) && i < maxlen; i++)
253 if ((raw[i] == '\\') || (raw[i] == '"'))
255 result[j++] = raw[i];
262 static void capa_probe(int sock, struct query *ctl)
263 /* set capability variables from a CAPA probe */
267 /* probe to see if we're running IMAP4 and can use RFC822.PEEK */
268 capabilities[0] = '\0';
269 if ((ok = gen_transact(sock, "CAPABILITY")) == PS_SUCCESS)
273 /* capability checks are supposed to be caseblind */
274 for (cp = capabilities; *cp; cp++)
277 /* UW-IMAP server 10.173 notifies in all caps, but RFC2060 says we
278 should expect a response in mixed-case */
279 if (strstr(capabilities, "IMAP4REV1"))
281 imap_version = IMAP4rev1;
282 if (outlevel >= O_DEBUG)
283 report(stdout, GT_("Protocol identified as IMAP4 rev 1\n"));
287 imap_version = IMAP4;
288 if (outlevel >= O_DEBUG)
289 report(stdout, GT_("Protocol identified as IMAP4 rev 0\n"));
292 else if (ok == PS_ERROR)
294 imap_version = IMAP2;
295 if (outlevel >= O_DEBUG)
296 report(stdout, GT_("Protocol identified as IMAP2 or IMAP2BIS\n"));
300 * Handle idling. We depend on coming through here on startup
301 * and after each timeout (including timeouts during idles).
306 if (strstr(capabilities, "IDLE"))
310 if (outlevel >= O_VERBOSE)
311 report(stdout, GT_("will idle after poll\n"));
314 peek_capable = (imap_version >= IMAP4);
317 static int imap_getauth(int sock, struct query *ctl, char *greeting)
318 /* apply for connection authorization */
322 flag did_stls = FALSE;
323 #endif /* SSL_ENABLE */
326 * Assumption: expunges are cheap, so we want to do them
327 * after every message unless user said otherwise.
329 if (NUM_SPECIFIED(ctl->expunge))
330 expunge_period = NUM_VALUE_OUT(ctl->expunge);
334 capa_probe(sock, ctl);
337 * If either (a) we saw a PREAUTH token in the greeting, or
338 * (b) the user specified ssh preauthentication, then we're done.
340 if (preauth || ctl->server.authenticate == A_SSH)
342 preauth = FALSE; /* reset for the next session */
347 if ((!ctl->sslproto || !strcmp(ctl->sslproto,"tls1"))
349 && strstr(capabilities, "STARTTLS"))
353 realhost = ctl->server.via ? ctl->server.via : ctl->server.pollname;
354 ok = gen_transact(sock, "STARTTLS");
356 /* We use "tls1" instead of ctl->sslproto, as we want STARTTLS,
357 * not other SSL protocols
359 if (ok == PS_SUCCESS &&
360 SSLOpen(sock,ctl->sslcert,ctl->sslkey,"tls1",ctl->sslcertck, ctl->sslcertpath,ctl->sslfingerprint,realhost,ctl->server.pollname) == -1)
362 if (!ctl->sslproto && !ctl->wehaveauthed)
364 ctl->sslproto = xstrdup("");
365 /* repoll immediately */
369 GT_("SSL connection failed.\n"));
375 * RFC 2595 says this:
377 * "Once TLS has been started, the client MUST discard cached
378 * information about server capabilities and SHOULD re-issue the
379 * CAPABILITY command. This is necessary to protect against
380 * man-in-the-middle attacks which alter the capabilities list prior
381 * to STARTTLS. The server MAY advertise different capabilities
384 capa_probe(sock, ctl);
386 #endif /* SSL_ENABLE */
389 * Time to authenticate the user.
390 * Try the protocol variants that don't require passwords first.
395 if ((ctl->server.authenticate == A_ANY
396 || ctl->server.authenticate == A_GSSAPI)
397 && strstr(capabilities, "AUTH=GSSAPI"))
399 if ((ok = do_gssauth(sock, "AUTHENTICATE", "imap",
400 ctl->server.truename, ctl->remotename)))
402 /* SASL cancellation of authentication */
404 if (ctl->server.authenticate != A_ANY)
413 if ((ctl->server.authenticate == A_ANY
414 || ctl->server.authenticate == A_KERBEROS_V4
415 || ctl->server.authenticate == A_KERBEROS_V5)
416 && strstr(capabilities, "AUTH=KERBEROS_V4"))
418 if ((ok = do_rfc1731(sock, "AUTHENTICATE", ctl->server.truename)))
420 /* SASL cancellation of authentication */
422 if(ctl->server.authenticate != A_ANY)
428 #endif /* KERBEROS_V4 */
431 * No such luck. OK, now try the variants that mask your password
432 * in a challenge-response.
435 if ((ctl->server.authenticate == A_ANY && strstr(capabilities, "AUTH=CRAM-MD5"))
436 || ctl->server.authenticate == A_CRAM_MD5)
438 if ((ok = do_cram_md5 (sock, "AUTHENTICATE", ctl, NULL)))
440 /* SASL cancellation of authentication */
442 if(ctl->server.authenticate != A_ANY)
450 if ((ctl->server.authenticate == A_ANY
451 || ctl->server.authenticate == A_OTP)
452 && strstr(capabilities, "AUTH=X-OTP")) {
453 if ((ok = do_otp(sock, "AUTHENTICATE", ctl)))
455 /* SASL cancellation of authentication */
457 if(ctl->server.authenticate != A_ANY)
464 if (ctl->server.authenticate == A_OTP)
467 GT_("Required OTP capability not compiled into fetchmail\n"));
469 #endif /* OPIE_ENABLE */
472 if ((ctl->server.authenticate == A_ANY
473 || ctl->server.authenticate == A_NTLM)
474 && strstr (capabilities, "AUTH=NTLM")) {
475 if ((ok = do_imap_ntlm(sock, ctl)))
477 /* SASL cancellation of authentication */
479 if(ctl->server.authenticate != A_ANY)
486 if (ctl->server.authenticate == A_NTLM)
489 GT_("Required NTLM capability not compiled into fetchmail\n"));
491 #endif /* NTLM_ENABLE */
493 #ifdef __UNUSED__ /* The Cyrus IMAP4rev1 server chokes on this */
494 /* this handles either AUTH=LOGIN or AUTH-LOGIN */
495 if ((imap_version >= IMAP4rev1) && (!strstr(capabilities, "LOGIN")))
498 GT_("Required LOGIN capability not supported by server\n"));
500 #endif /* __UNUSED__ */
503 * We're stuck with sending the password en clair.
504 * The reason for this odd-looking logic is that some
505 * servers return LOGINDISABLED even though login
506 * actually works. So arrange things in such a way that
507 * setting auth passwd makes it ignore this capability.
509 if((ctl->server.authenticate==A_ANY&&!strstr(capabilities,"LOGINDISABLED"))
510 || ctl->server.authenticate == A_PASSWORD)
512 /* these sizes guarantee no buffer overflow */
513 char *remotename, *password;
515 rnl = 2 * strlen(ctl->remotename) + 1;
516 pwl = 2 * strlen(ctl->password) + 1;
517 remotename = xmalloc(rnl);
518 password = xmalloc(pwl);
520 imap_canonicalize(remotename, ctl->remotename, rnl);
521 imap_canonicalize(password, ctl->password, pwl);
523 snprintf(shroud, sizeof (shroud), "\"%s\"", password);
524 ok = gen_transact(sock, "LOGIN \"%s\" \"%s\"", remotename, password);
529 /* this is for servers which claim to support TLS, but actually
531 if (did_stls && ok == PS_SOCKET && !ctl->sslproto && !ctl->wehaveauthed)
533 ctl->sslproto = xstrdup("");
534 /* repoll immediately */
540 /* SASL cancellation of authentication */
542 if(ctl->server.authenticate != A_ANY)
552 static int internal_expunge(int sock)
553 /* ship an expunge, resetting associated counters */
559 if ((ok = gen_transact(sock, "EXPUNGE")))
562 /* some servers do not report RECENT after an EXPUNGE. in this case,
563 * the previous value of recentcount is just ignored. */
567 expunged += deletions;
570 #ifdef IMAP_UID /* not used */
572 #endif /* IMAP_UID */
577 static int imap_idle(int sock)
578 /* start an RFC2177 IDLE, or fake one if unsupported */
583 saved_timeout = mytimeout;
586 /* special timeout to terminate the IDLE and re-issue it
587 * at least every 28 minutes:
588 * (the server may have an inactivity timeout) */
589 mytimeout = 1680; /* 28 min */
590 /* enter IDLE mode */
591 ok = gen_transact(sock, "IDLE");
593 if (ok == PS_IDLETIMEOUT) {
594 /* send "DONE" continuation */
595 SockWrite(sock, "DONE\r\n", 6);
596 if (outlevel >= O_MONITOR)
597 report(stdout, "IMAP> DONE\n");
599 /* not idle timeout */
601 } else { /* no idle support, fake it */
602 /* when faking an idle, we can't assume the server will
603 * send us the new messages out of the blue (RFC2060);
604 * this timeout is potentially the delay before we notice
605 * new mail (can be small since NOOP checking is cheap) */
607 ok = gen_transact(sock, "NOOP");
608 /* if there's an error (not likely) or we just found mail (stage
609 * has changed, timeout has also been restored), we're done */
610 if (ok != 0 || stage != STAGE_IDLE)
613 /* wait (briefly) for an unsolicited status update */
614 ok = imap_ok(sock, NULL);
615 /* again, this is new mail or an error */
616 if (ok != PS_IDLETIMEOUT)
620 /* restore normal timeout value */
621 mytimeout = saved_timeout;
624 /* get OK IDLE message */
626 return imap_ok(sock, NULL);
631 static int imap_getrange(int sock,
634 int *countp, int *newp, int *bytes)
635 /* get range of messages to be fetched */
638 char buf[MSGBUFSIZE+1], *cp;
640 /* find out how many messages are waiting */
645 /* deleted mails have already been expunged by
646 * end_mailbox_poll().
648 * recentcount is already set here by the last imap command which
649 * returned RECENT on detecting new mail. if recentcount is 0, wait
652 * this is a while loop because imap_idle() might return on other
653 * mailbox changes also */
654 while (recentcount == 0 && do_idle) {
656 ok = imap_idle(sock);
659 report(stderr, GT_("re-poll failed\n"));
663 /* if recentcount is 0, return no mail */
664 if (recentcount == 0)
666 if (outlevel >= O_DEBUG)
667 report(stdout, ngettext("%d message waiting after re-poll\n",
668 "%d messages waiting after re-poll\n",
674 ok = gen_transact(sock,
675 check_only ? "EXAMINE \"%s\"" : "SELECT \"%s\"",
676 folder ? folder : "INBOX");
679 report(stderr, GT_("mailbox selection failed\n"));
682 else if (outlevel >= O_DEBUG)
683 report(stdout, ngettext("%d message waiting after first poll\n",
684 "%d messages waiting after first poll\n",
687 /* no messages? then we may need to idle until we get some */
688 while (count == 0 && do_idle) {
689 ok = imap_idle(sock);
692 report(stderr, GT_("re-poll failed\n"));
698 * We should have an expunge here to
699 * a) avoid fetching deleted mails during 'fetchall'
700 * b) getting a wrong count of mails during 'no fetchall'
702 if (!check_only && !ctl->keep && count > 0)
704 ok = internal_expunge(sock);
707 report(stderr, GT_("expunge failed\n"));
710 if (outlevel >= O_DEBUG)
711 report(stdout, ngettext("%d message waiting after expunge\n",
712 "%d messages waiting after expunge\n",
721 /* OK, now get a count of unseen messages and their indices */
722 if (!ctl->fetchall && count > 0)
725 free(unseen_messages);
726 unseen_messages = xmalloc(count * sizeof(unsigned int));
727 memset(unseen_messages, 0, count * sizeof(unsigned int));
730 /* don't count deleted messages, in case user enabled keep last time */
731 gen_send(sock, "SEARCH UNSEEN NOT DELETED");
733 ok = gen_recv(sock, buf, sizeof(buf));
736 report(stderr, GT_("search for unseen messages failed\n"));
739 else if ((cp = strstr(buf, "* SEARCH")))
743 cp += 8; /* skip "* SEARCH" */
744 /* startcount is higher than count so that if there are no
745 * unseen messages, imap_getsizes() will not need to do
747 startcount = count + 1;
749 while (*cp && unseen < count)
751 /* skip whitespace */
752 while (*cp && isspace((unsigned char)*cp))
758 * Message numbers are between 1 and 2^32 inclusive,
759 * so unsigned int is large enough.
761 um=(unsigned int)strtol(cp,&ep,10);
764 unseen_messages[unseen++] = um;
765 if (outlevel >= O_DEBUG)
766 report(stdout, GT_("%u is unseen\n"), um);
775 (tag[0] != '\0' && strncmp(buf, tag, strlen(tag)));
777 if (outlevel >= O_DEBUG && unseen > 0)
778 report(stdout, GT_("%u is first unseen\n"), startcount);
789 static int imap_getpartialsizes(int sock, int first, int last, int *sizes)
790 /* capture the sizes of messages #first-#last */
792 char buf [MSGBUFSIZE+1];
795 * Some servers (as in, PMDF5.1-9.1 under OpenVMS 6.1)
796 * won't accept 1:1 as valid set syntax. Some implementors
797 * should be taken out and shot for excessive anality.
799 * Microsoft Exchange (brain-dead piece of crap that it is)
800 * sometimes gets its knickers in a knot about bodiless messages.
801 * You may see responses like this:
803 * fetchmail: IMAP> A0004 FETCH 1:9 RFC822.SIZE
804 * fetchmail: IMAP< * 2 FETCH (RFC822.SIZE 1187)
805 * fetchmail: IMAP< * 3 FETCH (RFC822.SIZE 3954)
806 * fetchmail: IMAP< * 4 FETCH (RFC822.SIZE 1944)
807 * fetchmail: IMAP< * 5 FETCH (RFC822.SIZE 2933)
808 * fetchmail: IMAP< * 6 FETCH (RFC822.SIZE 1854)
809 * fetchmail: IMAP< * 7 FETCH (RFC822.SIZE 34054)
810 * fetchmail: IMAP< * 8 FETCH (RFC822.SIZE 5561)
811 * fetchmail: IMAP< * 9 FETCH (RFC822.SIZE 1101)
812 * fetchmail: IMAP< A0004 NO The requested item could not be found.
814 * This means message 1 has only headers. For kicks and grins
815 * you can telnet in and look:
817 * A003 NO The requested item could not be found.
818 * A004 fetch 1 rfc822.header
819 * A004 NO The requested item could not be found.
821 * * 1 FETCH (BODY ("TEXT" "PLAIN" ("CHARSET" "US-ASCII") NIL NIL "7BIT" 35 3))
822 * A006 OK FETCH completed.
824 * To get around this, we terminate the read loop on a NO and count
825 * on the fact that the sizes array has been preinitialized with a
826 * known-bad size value.
829 /* expunges change the fetch numbers */
834 gen_send(sock, "FETCH %d RFC822.SIZE", last);
835 else if (last > first)
836 gen_send(sock, "FETCH %d:%d RFC822.SIZE", first, last);
837 else /* no unseen messages! */
841 unsigned int num, size;
845 if ((ok = gen_recv(sock, buf, sizeof(buf))))
847 /* we want response matching to be case-insensitive */
848 for (cp = buf; *cp; cp++)
850 /* an untagged NO means that a message was not readable */
851 if (strstr(buf, "* NO"))
853 else if (strstr(buf, "OK") || strstr(buf, "NO"))
855 else if (sscanf(buf, "* %u FETCH (RFC822.SIZE %u)", &num, &size) == 2)
857 if (num >= first && num <= last)
858 sizes[num - first] = size;
860 report(stderr, "Warning: ignoring bogus data for message sizes returned by the server.\n");
867 static int imap_getsizes(int sock, int count, int *sizes)
868 /* capture the sizes of all messages */
870 return imap_getpartialsizes(sock, 1, count, sizes);
873 static int imap_is_old(int sock, struct query *ctl, int number)
874 /* is the given message old? */
880 * Expunges change the fetch numbers, but unseen_messages contains
881 * indices from before any expungees were done. So neither the
882 * argument nor the values in message_sequence need to be decremented.
886 for (i = 0; i < unseen; i++)
887 if (unseen_messages[i] == number)
896 static char *skip_token(char *ptr)
898 while(isspace((unsigned char)*ptr)) ptr++;
899 while(!isspace((unsigned char)*ptr) && !iscntrl((unsigned char)*ptr)) ptr++;
900 while(isspace((unsigned char)*ptr)) ptr++;
904 static int imap_fetch_headers(int sock, struct query *ctl,int number,int *lenp)
905 /* request headers of nth message */
907 char buf [MSGBUFSIZE+1];
910 /* expunges change the fetch numbers */
914 * This is blessed by RFC1176, RFC1730, RFC2060.
915 * According to the RFCs, it should *not* set the \Seen flag.
917 gen_send(sock, "FETCH %d RFC822.HEADER", number);
919 /* looking for FETCH response */
925 if ((ok = gen_recv(sock, buf, sizeof(buf))))
927 ptr = skip_token(buf); /* either "* " or "AXXXX " */
928 if (sscanf(ptr, "%d FETCH (%*s {%d}", &num, lenp) == 2)
930 /* try to recover from chronically fucked-up M$ Exchange servers */
931 else if (!strncmp(ptr, "NO", 2))
933 /* wait for a tagged response */
934 if (strstr (buf, "* NO"))
936 return(PS_TRANSIENT);
938 else if (!strncmp(ptr, "BAD", 3))
940 /* wait for a tagged response */
941 if (strstr (buf, "* BAD"))
943 return(PS_TRANSIENT);
953 static int imap_fetch_body(int sock, struct query *ctl, int number, int *lenp)
954 /* request body of nth message */
956 char buf [MSGBUFSIZE+1], *cp;
959 /* expunges change the fetch numbers */
963 * If we're using IMAP4, we can fetch the message without setting its
964 * seen flag. This is good! It means that if the protocol exchange
965 * craps out during the message, it will still be marked `unseen' on
968 * According to RFC2060, and Mark Crispin the IMAP maintainer,
969 * FETCH %d BODY[TEXT] and RFC822.TEXT are "functionally
970 * equivalent". However, we know of at least one server that
971 * treats them differently in the presence of MIME attachments;
972 * the latter form downloads the attachment, the former does not.
973 * The server is InterChange, and the fool who implemented this
974 * misfeature ought to be strung up by his thumbs.
976 * When I tried working around this by disabling use of the 4rev1 form,
977 * I found that doing this breaks operation with M$ Exchange.
978 * Annoyingly enough, Exchange's refusal to cope is technically legal
979 * under RFC2062. Trust Microsoft, the Great Enemy of interoperability
980 * standards, to find a way to make standards compliance irritating....
982 switch (imap_version)
984 case IMAP4rev1: /* RFC 2060 */
985 gen_send(sock, "FETCH %d BODY.PEEK[TEXT]", number);
988 case IMAP4: /* RFC 1730 */
989 gen_send(sock, "FETCH %d RFC822.TEXT.PEEK", number);
992 default: /* RFC 1176 */
993 gen_send(sock, "FETCH %d RFC822.TEXT", number);
997 /* looking for FETCH response */
1001 if ((ok = gen_recv(sock, buf, sizeof(buf))))
1004 (!strstr(buf+4, "FETCH") || sscanf(buf+2, "%d", &num) != 1);
1010 * Try to extract a length from the FETCH response. RFC2060 requires
1011 * it to be present, but at least one IMAP server (Novell GroupWise)
1012 * botches this. The overflow check is needed because of a broken
1013 * server called dbmail that returns huge garbage lengths.
1015 if ((cp = strchr(buf, '{'))) {
1017 *lenp = (int)strtol(cp + 1, (char **)NULL, 10);
1018 if (errno == ERANGE && (*lenp == LONG_MAX || *lenp == LONG_MIN))
1019 *lenp = -1; /* length is too big/small for us to handle */
1022 *lenp = -1; /* missing length part in FETCH reponse */
1027 static int imap_trail(int sock, struct query *ctl, int number)
1028 /* discard tail of FETCH response after reading message text */
1030 /* expunges change the fetch numbers */
1031 /* number -= expunged; */
1035 char buf[MSGBUFSIZE+1];
1038 if ((ok = gen_recv(sock, buf, sizeof(buf))))
1041 /* UW IMAP returns "OK FETCH", Cyrus returns "OK Completed" */
1042 if (strstr(buf, "OK"))
1049 static int imap_delete(int sock, struct query *ctl, int number)
1050 /* set delete flag for given message */
1054 /* expunges change the fetch numbers */
1058 * Use SILENT if possible as a minor throughput optimization.
1059 * Note: this has been dropped from IMAP4rev1.
1061 * We set Seen because there are some IMAP servers (notably HP
1062 * OpenMail) that do message-receipt DSNs, but only when the seen
1063 * bit is set. This is the appropriate time -- we get here right
1064 * after the local SMTP response that says delivery was
1067 if ((ok = gen_transact(sock,
1068 imap_version == IMAP4
1069 ? "STORE %d +FLAGS.SILENT (\\Seen \\Deleted)"
1070 : "STORE %d +FLAGS (\\Seen \\Deleted)",
1077 * We do an expunge after expunge_period messages, rather than
1078 * just before quit, so that a line hit during a long session
1079 * won't result in lots of messages being fetched again during
1082 if (NUM_NONZERO(expunge_period) && (deletions % expunge_period) == 0)
1083 internal_expunge(sock);
1088 static int imap_mark_seen(int sock, struct query *ctl, int number)
1089 /* mark the given message as seen */
1091 return(gen_transact(sock,
1092 imap_version == IMAP4
1093 ? "STORE %d +FLAGS.SILENT (\\Seen)"
1094 : "STORE %d +FLAGS (\\Seen)",
1098 static int imap_end_mailbox_poll(int sock, struct query *ctl)
1099 /* cleanup mailbox before we idle or switch to another one */
1102 internal_expunge(sock);
1106 static int imap_logout(int sock, struct query *ctl)
1107 /* send logout command */
1109 /* if any un-expunged deletions remain, ship an expunge now */
1111 internal_expunge(sock);
1114 /* Memory clean-up */
1115 if (unseen_messages)
1116 free(unseen_messages);
1117 #endif /* USE_SEARCH */
1119 return(gen_transact(sock, "LOGOUT"));
1122 static const struct method imap =
1124 "IMAP", /* Internet Message Access Protocol */
1127 TRUE, /* this is a tagged protocol */
1128 FALSE, /* no message delimiter */
1129 imap_ok, /* parse command response */
1130 imap_getauth, /* get authorization */
1131 imap_getrange, /* query range of messages */
1132 imap_getsizes, /* get sizes of messages (used for ESMTP SIZE option) */
1133 imap_getpartialsizes, /* get sizes of subset of messages (used for ESMTP SIZE option) */
1134 imap_is_old, /* no UID check */
1135 imap_fetch_headers, /* request given message headers */
1136 imap_fetch_body, /* request given message body */
1137 imap_trail, /* eat message trailer */
1138 imap_delete, /* delete the message */
1139 imap_mark_seen, /* how to mark a message as seen */
1140 imap_end_mailbox_poll, /* end-of-mailbox processing */
1141 imap_logout, /* expunge and exit */
1142 TRUE, /* yes, we can re-poll */
1145 int doIMAP(struct query *ctl)
1146 /* retrieve messages using IMAP Version 2bis or Version 4 */
1148 return(do_protocol(ctl, &imap));
1151 /* imap.c ends here */