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 /* global variables: please reinitialize them explicitly for proper
28 * working in daemon mode */
30 /* TODO: session variables to be initialized before server greeting */
31 static int preauth = FALSE;
33 /* session variables initialized in capa_probe() or imap_getauth() */
34 static char capabilities[MSGBUFSIZE+1];
35 static int imap_version = IMAP4;
36 static flag do_idle = FALSE, has_idle = FALSE;
37 static int expunge_period = 1;
39 /* mailbox variables initialized in imap_getrange() */
40 static int count = 0, recentcount = 0, unseen = 0, deletions = 0;
41 static unsigned int startcount = 1;
42 static int expunged = 0;
43 static unsigned int *unseen_messages;
45 /* for "IMAP> EXPUNGE" */
46 static int actual_deletions = 0;
48 /* for "IMAP> IDLE" */
49 static int saved_timeout = 0;
51 static int imap_ok(int sock, char *argbuf)
52 /* parse command response */
54 char buf[MSGBUFSIZE+1];
60 if ((ok = gen_recv(sock, buf, sizeof(buf))))
63 /* all tokens in responses are caseblind */
64 for (cp = buf; *cp; cp++)
65 if (islower((unsigned char)*cp))
66 *cp = toupper((unsigned char)*cp);
68 /* interpret untagged status responses
69 * First check if we really have an untagged response, starting
70 * with "*" SPACE. Then, for each individual check, use a BLANK
71 * before the word to avoid confusion with the \Recent flag or
73 if (buf[0] == '*' && buf[1] == ' ') {
74 if (strstr(buf, " CAPABILITY")) {
75 strlcpy(capabilities, buf + 12, sizeof(capabilities));
77 else if (strstr(buf, " EXISTS"))
81 * Don't trust the message count passed by the server.
82 * Without this check, it might be possible to do a
83 * DNS-spoofing attack that would pass back a ridiculous
84 * count, and allocate a malloc area that would overlap
85 * a portion of the stack.
87 if (count > INT_MAX/sizeof(int))
89 report(stderr, GT_("bogus message count!"));
94 * Nasty kluge to handle RFC2177 IDLE. If we know we're idling
95 * we can't wait for the tag matching the IDLE; we have to tell the
96 * server the IDLE is finished by shipping back a DONE when we
97 * see an EXISTS. Only after that will a tagged response be
98 * shipped. The idling flag also gets cleared on a timeout.
100 if (stage == STAGE_IDLE)
102 /* If IDLE isn't supported, we were only sending NOOPs anyway. */
105 /* we do our own write and report here to disable tagging */
106 SockWrite(sock, "DONE\r\n", 6);
107 if (outlevel >= O_MONITOR)
108 report(stdout, "IMAP> DONE\n");
111 mytimeout = saved_timeout;
115 else if (strstr(buf, " RECENT"))
117 recentcount = atoi(buf+2);
119 else if (strstr(buf, " EXPUNGE"))
121 /* the response "* 10 EXPUNGE" means that the currently
122 * tenth (i.e. only one) message has been deleted */
127 /* Some servers do not report RECENT after an EXPUNGE.
128 * For such servers, assume that the mail being
129 * expunged is a recent one. For other servers, we
130 * should get an updated RECENT report later and this
131 * assumption will have no effect. */
137 else if (strstr(buf, " PREAUTH"))
142 * The server may decide to make the mailbox read-only,
143 * which causes fetchmail to go into a endless loop
144 * fetching the same message over and over again.
146 * However, for check_only, we use EXAMINE which will
147 * mark the mailbox read-only as per the RFC.
149 * This checks for the condition and aborts if
150 * the mailbox is read-only.
152 * See RFC 2060 section 6.3.1 (SELECT).
153 * See RFC 2060 section 6.3.2 (EXAMINE).
155 else if (!check_only && strstr(buf, "[READ-ONLY]"))
161 (tag[0] != '\0' && strncmp(buf, tag, strlen(tag)));
174 for (cp = buf; !isspace((unsigned char)*cp); cp++)
176 while (isspace((unsigned char)*cp))
179 if (strncasecmp(cp, "OK", 2) == 0)
185 else if (strncasecmp(cp, "BAD", 3) == 0)
187 else if (strncasecmp(cp, "NO", 2) == 0)
189 if (stage == STAGE_GETAUTH)
190 return(PS_AUTHFAIL); /* RFC2060, 6.2.2 */
203 * NTLM support by Grant Edwards.
205 * Handle MS-Exchange NTLM authentication method. This is the same
206 * as the NTLM auth used by Samba for SMB related services. We just
207 * encode the packets in base64 instead of sending them out via a
210 * Much source (ntlm.h, smb*.c smb*.h) was borrowed from Samba.
213 static int do_imap_ntlm(int sock, struct query *ctl)
215 tSmbNtlmAuthRequest request;
216 tSmbNtlmAuthChallenge challenge;
217 tSmbNtlmAuthResponse response;
222 gen_send(sock, "AUTHENTICATE NTLM");
224 if ((result = gen_recv(sock, msgbuf, sizeof msgbuf)))
227 if (msgbuf[0] != '+')
230 buildSmbNtlmAuthRequest(&request,ctl->remotename,NULL);
232 if (outlevel >= O_DEBUG)
233 dumpSmbNtlmAuthRequest(stdout, &request);
235 memset(msgbuf,0,sizeof msgbuf);
236 to64frombits (msgbuf, (unsigned char*)&request, SmbLength(&request));
238 if (outlevel >= O_MONITOR)
239 report(stdout, "IMAP> %s\n", msgbuf);
241 strcat(msgbuf,"\r\n");
242 SockWrite (sock, msgbuf, strlen (msgbuf));
244 if ((gen_recv(sock, msgbuf, sizeof msgbuf)))
247 len = from64tobits ((char*)&challenge, msgbuf, sizeof(challenge));
249 if (outlevel >= O_DEBUG)
250 dumpSmbNtlmAuthChallenge(stdout, &challenge);
252 buildSmbNtlmAuthResponse(&challenge, &response,ctl->remotename,ctl->password);
254 if (outlevel >= O_DEBUG)
255 dumpSmbNtlmAuthResponse(stdout, &response);
257 memset(msgbuf,0,sizeof msgbuf);
258 to64frombits (msgbuf, (unsigned char*)&response, SmbLength(&response));
260 if (outlevel >= O_MONITOR)
261 report(stdout, "IMAP> %s\n", msgbuf);
263 strcat(msgbuf,"\r\n");
264 SockWrite (sock, msgbuf, strlen (msgbuf));
266 if ((result = gen_recv (sock, msgbuf, sizeof msgbuf)))
269 if (strstr (msgbuf, "OK"))
276 static int imap_canonicalize(char *result, char *raw, int maxlen)
277 /* encode an IMAP password as per RFC1730's quoting conventions */
282 for (i = 0; i < strlen(raw) && i < maxlen; i++)
284 if ((raw[i] == '\\') || (raw[i] == '"'))
286 result[j++] = raw[i];
293 static void capa_probe(int sock, struct query *ctl)
294 /* set capability variables from a CAPA probe */
298 /* probe to see if we're running IMAP4 and can use RFC822.PEEK */
299 capabilities[0] = '\0';
300 if ((ok = gen_transact(sock, "CAPABILITY")) == PS_SUCCESS)
304 /* capability checks are supposed to be caseblind */
305 for (cp = capabilities; *cp; cp++)
306 *cp = toupper((unsigned char)*cp);
308 /* UW-IMAP server 10.173 notifies in all caps, but RFC2060 says we
309 should expect a response in mixed-case */
310 if (strstr(capabilities, "IMAP4REV1"))
312 imap_version = IMAP4rev1;
313 if (outlevel >= O_DEBUG)
314 report(stdout, GT_("Protocol identified as IMAP4 rev 1\n"));
318 imap_version = IMAP4;
319 if (outlevel >= O_DEBUG)
320 report(stdout, GT_("Protocol identified as IMAP4 rev 0\n"));
323 else if (ok == PS_ERROR)
325 imap_version = IMAP2;
326 if (outlevel >= O_DEBUG)
327 report(stdout, GT_("Protocol identified as IMAP2 or IMAP2BIS\n"));
331 * Handle idling. We depend on coming through here on startup
332 * and after each timeout (including timeouts during idles).
337 if (strstr(capabilities, "IDLE"))
341 if (outlevel >= O_VERBOSE)
342 report(stdout, GT_("will idle after poll\n"));
345 peek_capable = (imap_version >= IMAP4);
348 static int imap_getauth(int sock, struct query *ctl, char *greeting)
349 /* apply for connection authorization */
353 flag did_stls = FALSE;
354 #endif /* SSL_ENABLE */
357 * Assumption: expunges are cheap, so we want to do them
358 * after every message unless user said otherwise.
360 if (NUM_SPECIFIED(ctl->expunge))
361 expunge_period = NUM_VALUE_OUT(ctl->expunge);
365 capa_probe(sock, ctl);
368 * If either (a) we saw a PREAUTH token in the greeting, or
369 * (b) the user specified ssh preauthentication, then we're done.
371 if (preauth || ctl->server.authenticate == A_SSH)
373 preauth = FALSE; /* reset for the next session */
378 if ((!ctl->sslproto || !strcmp(ctl->sslproto,"tls1"))
380 && strstr(capabilities, "STARTTLS"))
384 realhost = ctl->server.via ? ctl->server.via : ctl->server.pollname;
385 ok = gen_transact(sock, "STARTTLS");
387 /* We use "tls1" instead of ctl->sslproto, as we want STARTTLS,
388 * not other SSL protocols
390 if (ok == PS_SUCCESS &&
391 SSLOpen(sock,ctl->sslcert,ctl->sslkey,"tls1",ctl->sslcertck, ctl->sslcertpath,ctl->sslfingerprint,realhost,ctl->server.pollname) == -1)
393 if (!ctl->sslproto && !ctl->wehaveauthed)
395 ctl->sslproto = xstrdup("");
396 /* repoll immediately */
400 GT_("SSL connection failed.\n"));
406 * RFC 2595 says this:
408 * "Once TLS has been started, the client MUST discard cached
409 * information about server capabilities and SHOULD re-issue the
410 * CAPABILITY command. This is necessary to protect against
411 * man-in-the-middle attacks which alter the capabilities list prior
412 * to STARTTLS. The server MAY advertise different capabilities
415 capa_probe(sock, ctl);
417 #endif /* SSL_ENABLE */
420 * Time to authenticate the user.
421 * Try the protocol variants that don't require passwords first.
426 if ((ctl->server.authenticate == A_ANY
427 || ctl->server.authenticate == A_GSSAPI)
428 && strstr(capabilities, "AUTH=GSSAPI"))
430 if ((ok = do_gssauth(sock, "AUTHENTICATE", "imap",
431 ctl->server.truename, ctl->remotename)))
433 /* SASL cancellation of authentication */
435 if (ctl->server.authenticate != A_ANY)
444 if ((ctl->server.authenticate == A_ANY
445 || ctl->server.authenticate == A_KERBEROS_V4
446 || ctl->server.authenticate == A_KERBEROS_V5)
447 && strstr(capabilities, "AUTH=KERBEROS_V4"))
449 if ((ok = do_rfc1731(sock, "AUTHENTICATE", ctl->server.truename)))
451 /* SASL cancellation of authentication */
453 if(ctl->server.authenticate != A_ANY)
459 #endif /* KERBEROS_V4 */
462 * No such luck. OK, now try the variants that mask your password
463 * in a challenge-response.
466 if ((ctl->server.authenticate == A_ANY && strstr(capabilities, "AUTH=CRAM-MD5"))
467 || ctl->server.authenticate == A_CRAM_MD5)
469 if ((ok = do_cram_md5 (sock, "AUTHENTICATE", ctl, NULL)))
471 /* SASL cancellation of authentication */
473 if(ctl->server.authenticate != A_ANY)
481 if ((ctl->server.authenticate == A_ANY
482 || ctl->server.authenticate == A_OTP)
483 && strstr(capabilities, "AUTH=X-OTP")) {
484 if ((ok = do_otp(sock, "AUTHENTICATE", ctl)))
486 /* SASL cancellation of authentication */
488 if(ctl->server.authenticate != A_ANY)
495 if (ctl->server.authenticate == A_OTP)
498 GT_("Required OTP capability not compiled into fetchmail\n"));
500 #endif /* OPIE_ENABLE */
503 if ((ctl->server.authenticate == A_ANY
504 || ctl->server.authenticate == A_NTLM)
505 && strstr (capabilities, "AUTH=NTLM")) {
506 if ((ok = do_imap_ntlm(sock, ctl)))
508 /* SASL cancellation of authentication */
510 if(ctl->server.authenticate != A_ANY)
517 if (ctl->server.authenticate == A_NTLM)
520 GT_("Required NTLM capability not compiled into fetchmail\n"));
522 #endif /* NTLM_ENABLE */
524 #ifdef __UNUSED__ /* The Cyrus IMAP4rev1 server chokes on this */
525 /* this handles either AUTH=LOGIN or AUTH-LOGIN */
526 if ((imap_version >= IMAP4rev1) && (!strstr(capabilities, "LOGIN")))
529 GT_("Required LOGIN capability not supported by server\n"));
531 #endif /* __UNUSED__ */
534 * We're stuck with sending the password en clair.
535 * The reason for this odd-looking logic is that some
536 * servers return LOGINDISABLED even though login
537 * actually works. So arrange things in such a way that
538 * setting auth passwd makes it ignore this capability.
540 if((ctl->server.authenticate==A_ANY&&!strstr(capabilities,"LOGINDISABLED"))
541 || ctl->server.authenticate == A_PASSWORD)
543 /* these sizes guarantee no buffer overflow */
544 char *remotename, *password;
546 rnl = 2 * strlen(ctl->remotename) + 1;
547 pwl = 2 * strlen(ctl->password) + 1;
548 remotename = xmalloc(rnl);
549 password = xmalloc(pwl);
551 imap_canonicalize(remotename, ctl->remotename, rnl);
552 imap_canonicalize(password, ctl->password, pwl);
554 snprintf(shroud, sizeof (shroud), "\"%s\"", password);
555 ok = gen_transact(sock, "LOGIN \"%s\" \"%s\"", remotename, password);
560 /* this is for servers which claim to support TLS, but actually
562 if (did_stls && ok == PS_SOCKET && !ctl->sslproto && !ctl->wehaveauthed)
564 ctl->sslproto = xstrdup("");
565 /* repoll immediately */
571 /* SASL cancellation of authentication */
573 if(ctl->server.authenticate != A_ANY)
583 static int internal_expunge(int sock)
584 /* ship an expunge, resetting associated counters */
588 actual_deletions = 0;
590 if ((ok = gen_transact(sock, "EXPUNGE")))
593 /* if there is a mismatch between the number of mails which should
594 * have been expunged and the number of mails actually expunged,
595 * another email client may be deleting mails. Quit here,
596 * otherwise fetchmail gets out-of-sync with the imap server,
597 * reports the wrong size to the SMTP server on MAIL FROM: and
598 * triggers a "message ... was not the expected length" error on
599 * every subsequent mail */
600 if (deletions > 0 && deletions != actual_deletions)
603 GT_("mail expunge mismatch (%d actual != %d expected)\n"),
604 actual_deletions, deletions);
609 expunged += deletions;
612 #ifdef IMAP_UID /* not used */
614 #endif /* IMAP_UID */
619 static int imap_idle(int sock)
620 /* start an RFC2177 IDLE, or fake one if unsupported */
625 saved_timeout = mytimeout;
628 /* special timeout to terminate the IDLE and re-issue it
629 * at least every 28 minutes:
630 * (the server may have an inactivity timeout) */
631 mytimeout = 1680; /* 28 min */
632 /* enter IDLE mode */
633 ok = gen_transact(sock, "IDLE");
635 if (ok == PS_IDLETIMEOUT) {
636 /* send "DONE" continuation */
637 SockWrite(sock, "DONE\r\n", 6);
638 if (outlevel >= O_MONITOR)
639 report(stdout, "IMAP> DONE\n");
641 /* not idle timeout */
643 } else { /* no idle support, fake it */
644 /* when faking an idle, we can't assume the server will
645 * send us the new messages out of the blue (RFC2060);
646 * this timeout is potentially the delay before we notice
647 * new mail (can be small since NOOP checking is cheap) */
649 ok = gen_transact(sock, "NOOP");
650 /* if there's an error (not likely) or we just found mail (stage
651 * has changed, timeout has also been restored), we're done */
652 if (ok != 0 || stage != STAGE_IDLE)
655 /* wait (briefly) for an unsolicited status update */
656 ok = imap_ok(sock, NULL);
657 /* again, this is new mail or an error */
658 if (ok != PS_IDLETIMEOUT)
662 /* restore normal timeout value */
663 mytimeout = saved_timeout;
666 /* get OK IDLE message */
668 return imap_ok(sock, NULL);
673 static int imap_getrange(int sock,
676 int *countp, int *newp, int *bytes)
677 /* get range of messages to be fetched */
680 char buf[MSGBUFSIZE+1], *cp;
682 /* find out how many messages are waiting */
687 /* deleted mails have already been expunged by
688 * end_mailbox_poll().
690 * recentcount is already set here by the last imap command which
691 * returned RECENT on detecting new mail. if recentcount is 0, wait
694 * this is a while loop because imap_idle() might return on other
695 * mailbox changes also */
696 while (recentcount == 0 && do_idle) {
698 ok = imap_idle(sock);
701 report(stderr, GT_("re-poll failed\n"));
705 /* if recentcount is 0, return no mail */
706 if (recentcount == 0)
708 if (outlevel >= O_DEBUG)
709 report(stdout, ngettext("%d message waiting after re-poll\n",
710 "%d messages waiting after re-poll\n",
716 ok = gen_transact(sock,
717 check_only ? "EXAMINE \"%s\"" : "SELECT \"%s\"",
718 folder ? folder : "INBOX");
719 /* imap_ok returns PS_LOCKBUSY for READ-ONLY folders,
720 * which we can safely use in fetchall keep only */
721 if (ok == PS_LOCKBUSY && ctl->fetchall && ctl-> keep)
726 report(stderr, GT_("mailbox selection failed\n"));
729 else if (outlevel >= O_DEBUG)
730 report(stdout, ngettext("%d message waiting after first poll\n",
731 "%d messages waiting after first poll\n",
734 /* no messages? then we may need to idle until we get some */
735 while (count == 0 && do_idle) {
736 ok = imap_idle(sock);
739 report(stderr, GT_("re-poll failed\n"));
745 * We should have an expunge here to
746 * a) avoid fetching deleted mails during 'fetchall'
747 * b) getting a wrong count of mails during 'no fetchall'
749 if (!check_only && !ctl->keep && count > 0)
751 ok = internal_expunge(sock);
754 report(stderr, GT_("expunge failed\n"));
757 if (outlevel >= O_DEBUG)
758 report(stdout, ngettext("%d message waiting after expunge\n",
759 "%d messages waiting after expunge\n",
768 /* OK, now get a count of unseen messages and their indices */
769 if (!ctl->fetchall && count > 0)
772 free(unseen_messages);
773 unseen_messages = xmalloc(count * sizeof(unsigned int));
774 memset(unseen_messages, 0, count * sizeof(unsigned int));
777 /* don't count deleted messages, in case user enabled keep last time */
778 gen_send(sock, "SEARCH UNSEEN NOT DELETED");
780 ok = gen_recv(sock, buf, sizeof(buf));
783 report(stderr, GT_("search for unseen messages failed\n"));
786 else if ((cp = strstr(buf, "* SEARCH")))
790 cp += 8; /* skip "* SEARCH" */
791 /* startcount is higher than count so that if there are no
792 * unseen messages, imap_getsizes() will not need to do
794 startcount = count + 1;
796 while (*cp && unseen < count)
798 /* skip whitespace */
799 while (*cp && isspace((unsigned char)*cp))
805 * Message numbers are between 1 and 2^32 inclusive,
806 * so unsigned int is large enough.
808 um=(unsigned int)strtol(cp,&ep,10);
811 unseen_messages[unseen++] = um;
812 if (outlevel >= O_DEBUG)
813 report(stdout, GT_("%u is unseen\n"), um);
822 (tag[0] != '\0' && strncmp(buf, tag, strlen(tag)));
824 if (outlevel >= O_DEBUG && unseen > 0)
825 report(stdout, GT_("%u is first unseen\n"), startcount);
836 static int imap_getpartialsizes(int sock, int first, int last, int *sizes)
837 /* capture the sizes of messages #first-#last */
839 char buf [MSGBUFSIZE+1];
842 * Some servers (as in, PMDF5.1-9.1 under OpenVMS 6.1)
843 * won't accept 1:1 as valid set syntax. Some implementors
844 * should be taken out and shot for excessive anality.
846 * Microsoft Exchange (brain-dead piece of crap that it is)
847 * sometimes gets its knickers in a knot about bodiless messages.
848 * You may see responses like this:
850 * fetchmail: IMAP> A0004 FETCH 1:9 RFC822.SIZE
851 * fetchmail: IMAP< * 2 FETCH (RFC822.SIZE 1187)
852 * fetchmail: IMAP< * 3 FETCH (RFC822.SIZE 3954)
853 * fetchmail: IMAP< * 4 FETCH (RFC822.SIZE 1944)
854 * fetchmail: IMAP< * 5 FETCH (RFC822.SIZE 2933)
855 * fetchmail: IMAP< * 6 FETCH (RFC822.SIZE 1854)
856 * fetchmail: IMAP< * 7 FETCH (RFC822.SIZE 34054)
857 * fetchmail: IMAP< * 8 FETCH (RFC822.SIZE 5561)
858 * fetchmail: IMAP< * 9 FETCH (RFC822.SIZE 1101)
859 * fetchmail: IMAP< A0004 NO The requested item could not be found.
861 * This means message 1 has only headers. For kicks and grins
862 * you can telnet in and look:
864 * A003 NO The requested item could not be found.
865 * A004 fetch 1 rfc822.header
866 * A004 NO The requested item could not be found.
868 * * 1 FETCH (BODY ("TEXT" "PLAIN" ("CHARSET" "US-ASCII") NIL NIL "7BIT" 35 3))
869 * A006 OK FETCH completed.
871 * To get around this, we terminate the read loop on a NO and count
872 * on the fact that the sizes array has been preinitialized with a
873 * known-bad size value.
876 /* expunges change the fetch numbers */
881 gen_send(sock, "FETCH %d RFC822.SIZE", last);
882 else if (last > first)
883 gen_send(sock, "FETCH %d:%d RFC822.SIZE", first, last);
884 else /* no unseen messages! */
888 unsigned int num, size;
892 if ((ok = gen_recv(sock, buf, sizeof(buf))))
894 /* we want response matching to be case-insensitive */
895 for (cp = buf; *cp; cp++)
896 *cp = toupper((unsigned char)*cp);
897 /* an untagged NO means that a message was not readable */
898 if (strstr(buf, "* NO"))
900 else if (strstr(buf, "OK") || strstr(buf, "NO"))
902 else if (sscanf(buf, "* %u FETCH (RFC822.SIZE %u)", &num, &size) == 2
903 /* some servers (like mail.internode.on.net bld-mail04) return UID information here
905 * IMAP> A0005 FETCH 1 RFC822.SIZE
906 * IMAP< * 1 FETCH (UID 16 RFC822.SIZE 1447)
907 * IMAP< A0005 OK FETCH completed
910 || sscanf(buf, "* %u FETCH (UID %*s RFC822.SIZE %u)", &num, &size) == 2)
912 if (num >= first && num <= last)
913 sizes[num - first] = size;
916 GT_("Warning: ignoring bogus data for message sizes returned by the server.\n"));
923 static int imap_getsizes(int sock, int count, int *sizes)
924 /* capture the sizes of all messages */
926 return imap_getpartialsizes(sock, 1, count, sizes);
929 static int imap_is_old(int sock, struct query *ctl, int number)
930 /* is the given message old? */
936 * Expunges change the fetch numbers, but unseen_messages contains
937 * indices from before any expungees were done. So neither the
938 * argument nor the values in message_sequence need to be decremented.
942 for (i = 0; i < unseen; i++)
943 if (unseen_messages[i] == number)
952 static char *skip_token(char *ptr)
954 while(isspace((unsigned char)*ptr)) ptr++;
955 while(!isspace((unsigned char)*ptr) && !iscntrl((unsigned char)*ptr)) ptr++;
956 while(isspace((unsigned char)*ptr)) ptr++;
960 static int imap_fetch_headers(int sock, struct query *ctl,int number,int *lenp)
961 /* request headers of nth message */
963 char buf [MSGBUFSIZE+1];
966 /* expunges change the fetch numbers */
970 * This is blessed by RFC1176, RFC1730, RFC2060.
971 * According to the RFCs, it should *not* set the \Seen flag.
973 gen_send(sock, "FETCH %d RFC822.HEADER", number);
975 /* looking for FETCH response */
981 if ((ok = gen_recv(sock, buf, sizeof(buf))))
983 ptr = skip_token(buf); /* either "* " or "AXXXX " */
984 if (sscanf(ptr, "%d FETCH (RFC822.HEADER {%d}", &num, lenp) == 2
985 /* some servers (like mail.internode.on.net bld-mail04) return UID information here
987 * IMAP> A0006 FETCH 1 RFC822.HEADER
988 * IMAP< * 1 FETCH (UID 16 RFC822.HEADER {1360}
991 * IMAP< A0006 OK FETCH completed
994 || sscanf(ptr, "%d FETCH (UID %*s RFC822.HEADER {%d}", &num, lenp) == 2)
996 /* try to recover from chronically fucked-up M$ Exchange servers */
997 else if (!strncmp(ptr, "NO", 2))
999 /* wait for a tagged response */
1000 if (strstr (buf, "* NO"))
1002 return(PS_TRANSIENT);
1004 else if (!strncmp(ptr, "BAD", 3))
1006 /* wait for a tagged response */
1007 if (strstr (buf, "* BAD"))
1009 return(PS_TRANSIENT);
1019 static int imap_fetch_body(int sock, struct query *ctl, int number, int *lenp)
1020 /* request body of nth message */
1022 char buf [MSGBUFSIZE+1], *cp;
1025 /* expunges change the fetch numbers */
1029 * If we're using IMAP4, we can fetch the message without setting its
1030 * seen flag. This is good! It means that if the protocol exchange
1031 * craps out during the message, it will still be marked `unseen' on
1034 * According to RFC2060, and Mark Crispin the IMAP maintainer,
1035 * FETCH %d BODY[TEXT] and RFC822.TEXT are "functionally
1036 * equivalent". However, we know of at least one server that
1037 * treats them differently in the presence of MIME attachments;
1038 * the latter form downloads the attachment, the former does not.
1039 * The server is InterChange, and the fool who implemented this
1040 * misfeature ought to be strung up by his thumbs.
1042 * When I tried working around this by disabling use of the 4rev1 form,
1043 * I found that doing this breaks operation with M$ Exchange.
1044 * Annoyingly enough, Exchange's refusal to cope is technically legal
1045 * under RFC2062. Trust Microsoft, the Great Enemy of interoperability
1046 * standards, to find a way to make standards compliance irritating....
1048 switch (imap_version)
1050 case IMAP4rev1: /* RFC 2060 */
1051 gen_send(sock, "FETCH %d BODY.PEEK[TEXT]", number);
1054 case IMAP4: /* RFC 1730 */
1055 gen_send(sock, "FETCH %d RFC822.TEXT.PEEK", number);
1058 default: /* RFC 1176 */
1059 gen_send(sock, "FETCH %d RFC822.TEXT", number);
1063 /* looking for FETCH response */
1067 if ((ok = gen_recv(sock, buf, sizeof(buf))))
1070 (!strstr(buf+4, "FETCH") || sscanf(buf+2, "%d", &num) != 1);
1076 * Try to extract a length from the FETCH response. RFC2060 requires
1077 * it to be present, but at least one IMAP server (Novell GroupWise)
1078 * botches this. The overflow check is needed because of a broken
1079 * server called dbmail that returns huge garbage lengths.
1081 if ((cp = strchr(buf, '{'))) {
1083 *lenp = (int)strtol(cp + 1, (char **)NULL, 10);
1084 if (errno == ERANGE || *lenp < 0)
1085 *lenp = -1; /* length is too big/small for us to handle */
1088 *lenp = -1; /* missing length part in FETCH reponse */
1093 static int imap_trail(int sock, struct query *ctl, int number, const char *tag)
1094 /* discard tail of FETCH response after reading message text */
1096 /* expunges change the fetch numbers */
1097 /* number -= expunged; */
1101 char buf[MSGBUFSIZE+1], *t;
1104 if ((ok = gen_recv(sock, buf, sizeof(buf))))
1107 /* UW IMAP returns "OK FETCH", Cyrus returns "OK Completed" */
1108 if (strncmp(buf, tag, strlen(tag)) == 0) {
1109 t = buf + strlen(tag);
1110 t += strspn(t, " \t");
1111 if (strncmp(t, "OK", 2) == 0)
1119 static int imap_delete(int sock, struct query *ctl, int number)
1120 /* set delete flag for given message */
1124 /* expunges change the fetch numbers */
1128 * Use SILENT if possible as a minor throughput optimization.
1129 * Note: this has been dropped from IMAP4rev1.
1131 * We set Seen because there are some IMAP servers (notably HP
1132 * OpenMail) that do message-receipt DSNs, but only when the seen
1133 * bit is set. This is the appropriate time -- we get here right
1134 * after the local SMTP response that says delivery was
1137 if ((ok = gen_transact(sock,
1138 imap_version == IMAP4
1139 ? "STORE %d +FLAGS.SILENT (\\Seen \\Deleted)"
1140 : "STORE %d +FLAGS (\\Seen \\Deleted)",
1147 * We do an expunge after expunge_period messages, rather than
1148 * just before quit, so that a line hit during a long session
1149 * won't result in lots of messages being fetched again during
1152 if (NUM_NONZERO(expunge_period) && (deletions % expunge_period) == 0)
1154 if ((ok = internal_expunge(sock)))
1161 static int imap_mark_seen(int sock, struct query *ctl, int number)
1162 /* mark the given message as seen */
1164 return(gen_transact(sock,
1165 imap_version == IMAP4
1166 ? "STORE %d +FLAGS.SILENT (\\Seen)"
1167 : "STORE %d +FLAGS (\\Seen)",
1171 static int imap_end_mailbox_poll(int sock, struct query *ctl)
1172 /* cleanup mailbox before we idle or switch to another one */
1175 internal_expunge(sock);
1179 static int imap_logout(int sock, struct query *ctl)
1180 /* send logout command */
1182 /* if any un-expunged deletions remain, ship an expunge now */
1184 internal_expunge(sock);
1187 /* Memory clean-up */
1188 if (unseen_messages)
1189 free(unseen_messages);
1190 #endif /* USE_SEARCH */
1192 return(gen_transact(sock, "LOGOUT"));
1195 static const struct method imap =
1197 "IMAP", /* Internet Message Access Protocol */
1200 TRUE, /* this is a tagged protocol */
1201 FALSE, /* no message delimiter */
1202 imap_ok, /* parse command response */
1203 imap_getauth, /* get authorization */
1204 imap_getrange, /* query range of messages */
1205 imap_getsizes, /* get sizes of messages (used for ESMTP SIZE option) */
1206 imap_getpartialsizes, /* get sizes of subset of messages (used for ESMTP SIZE option) */
1207 imap_is_old, /* no UID check */
1208 imap_fetch_headers, /* request given message headers */
1209 imap_fetch_body, /* request given message body */
1210 imap_trail, /* eat message trailer */
1211 imap_delete, /* delete the message */
1212 imap_mark_seen, /* how to mark a message as seen */
1213 imap_end_mailbox_poll, /* end-of-mailbox processing */
1214 imap_logout, /* expunge and exit */
1215 TRUE, /* yes, we can re-poll */
1218 int doIMAP(struct query *ctl)
1219 /* retrieve messages using IMAP Version 2bis or Version 4 */
1221 return(do_protocol(ctl, &imap));
1224 /* imap.c ends here */