2 * pop3.c -- POP3 protocol methods
4 * Copyright 1998 by Eric S. Raymond.
5 * For license terms, see the file COPYING in this directory.
13 #if defined(HAVE_UNISTD_H)
16 #if defined(STDC_HEADERS)
21 #include "fetchmail.h"
33 #endif /* OPIE_ENABLE */
35 /* global variables: please reinitialize them explicitly for proper
36 * working in daemon mode */
38 /* TODO: session variables to be initialized before server greeting */
40 static char lastok[POPBUFSIZE+1];
41 #endif /* OPIE_ENABLE */
43 /* session variables initialized in capa_probe() or pop3_getauth() */
45 flag has_gssapi = FALSE;
46 #endif /* defined(GSSAPI) */
47 #if defined(KERBEROS_V4) || defined(KERBEROS_V5)
48 flag has_kerberos = FALSE;
49 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
50 static flag has_cram = FALSE;
53 #endif /* OPIE_ENABLE */
55 static flag has_ssl = FALSE;
56 #endif /* SSL_ENABLE */
58 /* mailbox variables initialized in pop3_getrange() */
61 /* mail variables initialized in pop3_fetch() */
65 #endif /* SDPS_ENABLE */
71 * NTLM support by Grant Edwards.
73 * Handle MS-Exchange NTLM authentication method. This is the same
74 * as the NTLM auth used by Samba for SMB related services. We just
75 * encode the packets in base64 instead of sending them out via a
78 * Much source (ntlm.h, smb*.c smb*.h) was borrowed from Samba.
81 static int do_pop3_ntlm(int sock, struct query *ctl,
82 int msn_instead /** if true, send AUTH MSN, else send AUTH NTLM */)
84 tSmbNtlmAuthRequest request;
85 tSmbNtlmAuthChallenge challenge;
86 tSmbNtlmAuthResponse response;
91 gen_send(sock, msn_instead ? "AUTH MSN" : "AUTH NTLM");
93 if ((result = gen_recv(sock, msgbuf, sizeof msgbuf)))
99 buildSmbNtlmAuthRequest(&request,ctl->remotename,NULL);
101 if (outlevel >= O_DEBUG)
102 dumpSmbNtlmAuthRequest(stdout, &request);
104 memset(msgbuf,0,sizeof msgbuf);
105 to64frombits (msgbuf, &request, SmbLength(&request));
107 if (outlevel >= O_MONITOR)
108 report(stdout, "POP3> %s\n", msgbuf);
110 strcat(msgbuf,"\r\n");
111 SockWrite (sock, msgbuf, strlen (msgbuf));
113 if ((gen_recv(sock, msgbuf, sizeof msgbuf)))
116 len = from64tobits (&challenge, msgbuf, sizeof(msgbuf));
118 if (outlevel >= O_DEBUG)
119 dumpSmbNtlmAuthChallenge(stdout, &challenge);
121 buildSmbNtlmAuthResponse(&challenge, &response,ctl->remotename,ctl->password);
123 if (outlevel >= O_DEBUG)
124 dumpSmbNtlmAuthResponse(stdout, &response);
126 memset(msgbuf,0,sizeof msgbuf);
127 to64frombits (msgbuf, &response, SmbLength(&response));
129 if (outlevel >= O_MONITOR)
130 report(stdout, "POP3> %s\n", msgbuf);
132 strcat(msgbuf,"\r\n");
133 SockWrite (sock, msgbuf, strlen (msgbuf));
135 if ((result = gen_recv (sock, msgbuf, sizeof msgbuf)))
138 if (strstr (msgbuf, "OK"))
146 #define DOTLINE(s) (s[0] == '.' && (s[1]=='\r'||s[1]=='\n'||s[1]=='\0'))
148 static int pop3_ok (int sock, char *argbuf)
149 /* parse command response */
152 char buf [POPBUFSIZE+1];
155 if ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
157 if (*bufp == '+' || *bufp == '-')
162 while (isalpha((unsigned char)*bufp))
168 if (strcmp(buf,"+OK") == 0)
171 strcpy(lastok, bufp);
172 #endif /* OPIE_ENABLE */
175 else if (strncmp(buf,"-ERR", 4) == 0)
177 if (stage == STAGE_FETCH)
179 else if (stage > STAGE_GETAUTH)
182 * We're checking for "lock busy", "unable to lock",
183 * "already locked", "wait a few minutes" etc. here.
184 * This indicates that we have to wait for the server to
185 * unwedge itself before we can poll again.
187 * PS_LOCKBUSY check empirically verified with two recent
188 * versions of the Berkeley popper; QPOP (version 2.2) and
189 * QUALCOMM Pop server derived from UCB (version 2.1.4-R3)
190 * These are caught by the case-indifferent "lock" check.
191 * The "wait" catches "mail storage services unavailable,
192 * wait a few minutes and try again" on the InterMail server.
194 * If these aren't picked up on correctly, fetchmail will
195 * think there is an authentication failure and wedge the
196 * connection in order to prevent futile polls.
200 else if (strstr(bufp,"lock")
201 || strstr(bufp,"Lock")
202 || strstr(bufp,"LOCK")
203 || strstr(bufp,"wait")
204 /* these are blessed by RFC 2449 */
205 || strstr(bufp,"[IN-USE]")||strstr(bufp,"[LOGIN-DELAY]"))
207 else if ((strstr(bufp,"Service")
208 || strstr(bufp,"service"))
209 && (strstr(bufp,"unavailable")))
214 * We always want to pass the user lock-busy messages, because
215 * they're red flags. Other stuff (like AUTH failures on non-
216 * RFC1734 servers) only if we're debugging.
218 if (*bufp && (ok == PS_LOCKBUSY || outlevel >= O_MONITOR))
219 report(stderr, "%s\n", bufp);
224 #if POPBUFSIZE > MSGBUFSIZE
225 #error "POPBUFSIZE must not be larger than MSGBUFSIZE"
236 static int capa_probe(int sock)
237 /* probe the capabilities of the remote server */
243 #endif /* defined(GSSAPI) */
244 #if defined(KERBEROS_V4) || defined(KERBEROS_V5)
245 has_kerberos = FALSE;
246 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
250 #endif /* OPIE_ENABLE */
252 ok = gen_transact(sock, "CAPA");
253 if (ok == PS_SUCCESS)
257 /* determine what authentication methods we have available */
258 while ((ok = gen_recv(sock, buffer, sizeof(buffer))) == 0)
263 if (strstr(buffer, "STLS"))
265 #endif /* SSL_ENABLE */
267 if (strstr(buffer, "GSSAPI"))
269 #endif /* defined(GSSAPI) */
270 #if defined(KERBEROS_V4)
271 if (strstr(buffer, "KERBEROS_V4"))
273 #endif /* defined(KERBEROS_V4) */
275 if (strstr(buffer, "X-OTP"))
277 #endif /* OPIE_ENABLE */
278 if (strstr(buffer, "CRAM-MD5"))
285 static void set_peek_capable(struct query *ctl)
287 /* we're peek-capable means that the use of TOP is enabled,
288 * see pop3_fetch for details - short story, we can use TOP if
289 * we have a means of reliably tracking which mail we need to
290 * refetch should the connection abort in the middle.
291 * fetchall forces RETR, as does keep without UIDL */
292 peek_capable = !ctl->fetchall && (!ctl->keep || ctl->server.uidl);
295 static int pop3_getauth(int sock, struct query *ctl, char *greeting)
296 /* apply for connection authorization */
303 #endif /* OPIE_ENABLE */
305 flag did_stls = FALSE;
306 flag using_tls = FALSE;
307 #endif /* SSL_ENABLE */
311 #endif /* defined(GSSAPI) */
312 #if defined(KERBEROS_V4) || defined(KERBEROS_V5)
313 has_kerberos = FALSE;
314 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
318 #endif /* OPIE_ENABLE */
321 #endif /* SSL_ENABLE */
323 /* Set this up before authentication quits early. */
324 set_peek_capable(ctl);
326 * The "Maillennium POP3/PROXY server" deliberately truncates
327 * TOP replies after c. 64 or 80 kByte (we have varying reports), so
328 * disable TOP. Comcast once spewed marketing babble to the extent
329 * of protecting Outlook -- pretty overzealous to break a protocol
330 * for that that Microsoft could have read, too. Comcast aren't
331 * alone in using this software though.
332 * <http://lists.ccil.org/pipermail/fetchmail-friends/2004-April/008523.html>
333 * (Thanks to Ed Wilts for reminding me of that.)
335 * The warning is printed once per server, until fetchmail exits.
336 * It will be suppressed when --fetchall or other circumstances make
337 * us use RETR anyhow.
341 if (peek_capable && strstr(greeting, "Maillennium POP3/PROXY server")) {
342 if ((ctl->server.workarounds & WKA_TOP) == 0) {
343 report(stdout, GT_("Warning: \"Maillennium POP3/PROXY server\" found, using RETR command instead of TOP.\n"));
344 ctl->server.workarounds |= WKA_TOP;
348 if (ctl->server.authenticate == A_SSH) {
354 * This needs to catch both demon.co.uk and demon.net.
355 * If we see either, and we're in multidrop mode, try to use
356 * the SDPS *ENV extension.
358 if (!(ctl->server.sdps) && MULTIDROP(ctl) && strstr(greeting, "demon."))
359 ctl->server.sdps = TRUE;
360 #endif /* SDPS_ENABLE */
363 /* MSN servers require the use of NTLM (MSN) authentication */
364 if (!strcasecmp(ctl->server.pollname, "pop3.email.msn.com") ||
365 ctl->server.authenticate == A_MSN)
366 return (do_pop3_ntlm(sock, ctl, 1) == 0) ? PS_SUCCESS : PS_AUTHFAIL;
367 if (ctl->server.authenticate == A_NTLM)
368 return (do_pop3_ntlm(sock, ctl, 0) == 0) ? PS_SUCCESS : PS_AUTHFAIL;
370 if (ctl->server.authenticate == A_NTLM || ctl->server.authenticate == A_MSN)
373 GT_("Required NTLM capability not compiled into fetchmail\n"));
377 switch (ctl->server.protocol) {
380 /* XXX FIXME: AUTH probing (RFC1734) should become global */
381 /* CompuServe POP3 Servers as of 990730 want AUTH first for RPA */
382 if (strstr(ctl->remotename, "@compuserve.com"))
384 /* AUTH command should return a list of available mechanisms */
385 if (gen_transact(sock, "AUTH") == 0)
388 flag has_rpa = FALSE;
390 while ((ok = gen_recv(sock, buffer, sizeof(buffer))) == 0)
394 if (strncasecmp(buffer, "rpa", 3) == 0)
397 if (has_rpa && !POP3_auth_rpa(ctl->remotename,
398 ctl->password, sock))
404 #endif /* RPA_ENABLE */
407 * CAPA command may return a list including available
408 * authentication mechanisms. if it doesn't, no harm done, we
409 * just fall back to a plain login. Note that this code
410 * latches the server's authentication type, so that in daemon mode
411 * the CAPA check only needs to be done once at start of run.
413 * If CAPA fails, then force the authentication method to PASSORD
414 * and repoll immediately.
416 * These authentication methods are blessed by RFC1734,
417 * describing the POP3 AUTHentication command.
419 if ((ctl->server.authenticate == A_ANY) ||
420 (ctl->server.authenticate == A_GSSAPI) ||
421 (ctl->server.authenticate == A_KERBEROS_V4) ||
422 (ctl->server.authenticate == A_OTP) ||
423 (ctl->server.authenticate == A_CRAM_MD5))
425 if ((ok = capa_probe(sock)) != PS_SUCCESS)
426 /* we are in STAGE_GETAUTH! */
427 if (ok == PS_AUTHFAIL ||
428 /* Some servers directly close the socket. However, if we
429 * have already authenticated before, then a previous CAPA
430 * must have succeeded. In that case, treat this as a
431 * genuine socket error and do not change the auth method.
433 (ok == PS_SOCKET && !ctl->wehaveauthed))
435 ctl->server.authenticate = A_PASSWORD;
436 /* repoll immediately with PASS authentication */
445 && (!ctl->sslproto || !strcasecmp(ctl->sslproto,"tls1")))
449 realhost = ctl->server.via ? ctl->server.via : ctl->server.pollname;
450 ok = gen_transact(sock, "STLS");
452 /* We use "tls1" instead of ctl->sslproto, as we want STLS,
453 * not other SSL protocols */
454 if (ok == PS_SUCCESS &&
455 SSLOpen(sock,ctl->sslcert,ctl->sslkey,"tls1",ctl->sslcertck,
456 ctl->sslcertpath,ctl->sslfingerprint,
457 realhost,ctl->server.pollname,&ctl->remotename) == -1)
459 if (!ctl->sslproto && !ctl->wehaveauthed)
461 ctl->sslproto = xstrdup("");
462 /* repoll immediately without TLS */
466 GT_("TLS connection failed.\n"));
469 if (outlevel >= O_VERBOSE && !ctl->sslproto)
470 report(stdout, GT_("%s: opportunistic upgrade to TLS.\n"), realhost);
476 * RFC 2595 says this:
478 * "Once TLS has been started, the client MUST discard cached
479 * information about server capabilities and SHOULD re-issue the
480 * CAPABILITY command. This is necessary to protect against
481 * man-in-the-middle attacks which alter the capabilities list prior
482 * to STARTTLS. The server MAY advertise different capabilities
487 if ((ctl->sslproto && !strcasecmp(ctl->sslproto,"tls1")) && !ctl->use_ssl && !using_tls) {
489 GT_("TLS connection failed.\n"));
493 #endif /* SSL_ENABLE */
496 * OK, we have an authentication type now.
498 #if defined(KERBEROS_V4)
500 * Servers doing KPOP have to go through a dummy login sequence
501 * rather than doing SASL.
504 ctl->server.service && (strcmp(ctl->server.service, KPOP_PORT)!=0)
505 && (ctl->server.authenticate == A_KERBEROS_V4
506 || ctl->server.authenticate == A_KERBEROS_V5
507 || ctl->server.authenticate == A_ANY))
509 ok = do_rfc1731(sock, "AUTH", ctl->server.truename);
510 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
513 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
517 (ctl->server.authenticate == A_GSSAPI ||
518 ctl->server.authenticate == A_ANY))
520 ok = do_gssauth(sock,"AUTH","pop",ctl->server.truename,ctl->remotename);
521 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
524 #endif /* defined(GSSAPI) */
528 (ctl->server.authenticate == A_OTP ||
529 ctl->server.authenticate == A_ANY))
531 ok = do_otp(sock, "AUTH", ctl);
532 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
535 #endif /* OPIE_ENABLE */
537 if (ctl->server.authenticate == A_CRAM_MD5 ||
538 (has_cram && ctl->server.authenticate == A_ANY))
540 ok = do_cram_md5(sock, "AUTH", ctl, NULL);
541 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
545 /* ordinary validation, no one-time password or RPA */
546 if ((ok = gen_transact(sock, "USER %s", ctl->remotename)))
550 /* see RFC1938: A One-Time Password System */
551 if ((challenge = strstr(lastok, "otp-"))) {
552 char response[OPIE_RESPONSE_MAX+1];
554 char *n = xstrdup("");
556 i = opiegenerator(challenge, !strcmp(ctl->password, "opie") ? n : ctl->password, response);
558 if ((i == -2) && !run.poll_interval) {
559 char secret[OPIE_SECRET_MAX+1];
560 fprintf(stderr, GT_("Secret pass phrase: "));
561 if (opiereadpass(secret, sizeof(secret), 0))
562 i = opiegenerator(challenge, secret, response);
563 memset(secret, 0, sizeof(secret));
571 ok = gen_transact(sock, "PASS %s", response);
574 #endif /* OPIE_ENABLE */
576 strlcpy(shroud, ctl->password, sizeof(shroud));
577 ok = gen_transact(sock, "PASS %s", ctl->password);
580 /* this is for servers which claim to support TLS, but actually
582 if (did_stls && ok == PS_SOCKET && !ctl->sslproto && !ctl->wehaveauthed)
584 ctl->sslproto = xstrdup("");
585 /* repoll immediately without TLS */
592 /* build MD5 digest from greeting timestamp + password */
593 /* find start of timestamp */
594 for (start = greeting; *start != 0 && *start != '<'; start++)
598 GT_("Required APOP timestamp not found in greeting\n"));
602 /* find end of timestamp */
603 for (end = start; *end != 0 && *end != '>'; end++)
605 if (*end == 0 || end == start + 1) {
607 GT_("Timestamp syntax error in greeting\n"));
613 /* copy timestamp and password into digestion buffer */
614 msg = xmalloc((end-start+1) + strlen(ctl->password) + 1);
616 strcat(msg,ctl->password);
617 strcpy(ctl->digest, MD5Digest((unsigned char *)msg));
620 ok = gen_transact(sock, "APOP %s %s", ctl->remotename, ctl->digest);
624 if ((ok = gen_transact(sock,"USER %s", ctl->remotename)) == 0)
625 ok = gen_transact(sock, "RPOP %s", ctl->password);
629 report(stderr, GT_("Undefined protocol request in POP3_auth\n"));
635 /* maybe we detected a lock-busy condition? */
636 if (ok == PS_LOCKBUSY)
637 report(stderr, GT_("lock busy! Is another session active?\n"));
642 /* Disable the sleep. Based on patch by Brian Candler 2004-04-19/2004-11-08,
643 * accepted by Matthias Andree.
645 * Rationale: the server must have locked the spool before returning +OK;
646 * this sleep just wastes time and hence, for modem and GSM CSD users, money. */
649 * Empirical experience shows some server/OS combinations
650 * may need a brief pause even after any lockfiles on the
651 * server are released, to give the server time to finish
652 * copying back very large mailfolders from the temp-file...
653 * this is only ever an issue with extremely large mailboxes.
655 sleep(3); /* to be _really_ safe, probably need sleep(5)! */
662 /* cut off C string at first POSIX space */
663 static void trim(char *s) {
664 s += strcspn(s, POSIX_space);
668 /* XXX FIXME: using the Message-ID is unsafe, some messages (spam,
669 * broken messages) do not have Message-ID headers, and messages without
670 * those appear to break this code and cause fetchmail (at least version
671 * 6.2.3) to not delete such messages properly after retrieval.
672 * See Sourceforge Bug #780933.
674 * The other problem is that the TOP command itself is optional, too... */
675 static int pop3_gettopid(int sock, int num , char *id, size_t idsize)
679 char buf [POPBUFSIZE+1];
680 snprintf(buf, sizeof(buf), "TOP %d 1", num);
681 if ((ok = gen_transact(sock, buf )) != 0)
684 while ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
688 if (!got_it && 0 == strncasecmp("Message-Id:", buf, 11)) {
691 p += strspn(p, POSIX_space);
692 strlcpy(id, p, idsize);
696 /* XXX FIXME: do not return success here if no Message-ID header was
701 /** Parse the UID response (leading +OK must have been
702 * stripped off) in buf, store the number in gotnum, and store the ID
703 * into the caller-provided buffer "id" of size "idsize".
704 * Returns PS_SUCCESS or PS_PROTOCOL for failure. */
705 static int parseuid(const char *buf, unsigned long *gotnum, char *id, size_t idsize)
710 /* skip leading blanks ourselves */
712 i += strspn(i, POSIX_space);
714 *gotnum = strtoul(i, &j, 10);
715 if (j == i || !*j || errno || NULL == strchr(POSIX_space, *j)) {
716 report(stderr, GT_("Cannot handle UIDL response from upstream server.\n"));
719 j += strspn(j, POSIX_space);
720 strlcpy(id, j, idsize);
725 /** request UIDL for single message \a num and stuff the result into the
726 * buffer \a id which can hold \a idsize bytes */
727 static int pop3_getuidl(int sock, int num, char *id /** output */, size_t idsize)
730 char buf [POPBUFSIZE+1];
731 unsigned long gotnum;
733 gen_send(sock, "UIDL %d", num);
734 if ((ok = pop3_ok(sock, buf)) != 0)
736 if ((ok = parseuid(buf, &gotnum, id, idsize)))
738 if (gotnum != (unsigned long)num) {
739 report(stderr, GT_("Server responded with UID for wrong message.\n"));
745 static int pop3_fastuidl( int sock, struct query *ctl, unsigned int count, int *newp)
748 unsigned int first_nr, last_nr, try_nr;
753 while (first_nr < last_nr - 1)
757 try_nr = (first_nr + last_nr) / 2;
758 if ((ok = pop3_getuidl(sock, try_nr, id, sizeof(id))) != 0)
760 if ((newl = str_in_list(&ctl->oldsaved, id, FALSE)))
762 flag mark = newl->val.status.mark;
763 if (mark == UID_DELETED || mark == UID_EXPUNGED)
765 if (outlevel >= O_VERBOSE)
766 report(stderr, GT_("id=%s (num=%d) was deleted, but is still present!\n"), id, try_nr);
767 /* just mark it as seen now! */
768 newl->val.status.mark = mark = UID_SEEN;
771 /* narrow the search region! */
772 if (mark == UID_UNSEEN)
774 if (outlevel >= O_DEBUG)
775 report(stdout, GT_("%u is unseen\n"), try_nr);
781 /* save the number */
782 newl->val.status.num = try_nr;
786 if (outlevel >= O_DEBUG)
787 report(stdout, GT_("%u is unseen\n"), try_nr);
791 newl = save_str(&ctl->oldsaved, id, UID_UNSEEN);
792 newl->val.status.num = try_nr;
795 if (outlevel >= O_DEBUG && last_nr <= count)
796 report(stdout, GT_("%u is first unseen\n"), last_nr);
799 *newp = count - first_nr;
804 static int pop3_slowuidl( int sock, struct query *ctl, int *countp, int *newp)
806 /* XXX FIXME: this code is severely broken. A Cc:d mailing list
807 * message will arrive twice with the same Message-ID, so this
808 * slowuidl code will break. Same goes for messages without
809 * Message-ID headers at all. This code would best be removed. */
810 /* This approach tries to get the message headers from the
811 * remote hosts and compares the message-id to the already known
813 * + if the first message containes a new id, all messages on
814 * the server will be new
815 * + if the first is known, try to estimate the last known message
816 * on the server and check. If this works you know the total number
817 * of messages to get.
818 * + Otherwise run a binary search to determine the last known message
820 int ok, nolinear = 0;
821 int first_nr, list_len, try_id, try_nr, add_id;
825 if ((ok = pop3_gettopid(sock, 1, id, sizeof(id))) != 0)
828 if( ( first_nr = str_nr_in_list(&ctl->oldsaved, id) ) == -1 ) {
829 /* the first message is unknown -> all messages are new */
834 /* check where we expect the latest known message */
835 list_len = count_list( &ctl->oldsaved );
836 try_id = list_len - first_nr; /* -1 + 1 */
838 if( try_id <= *countp ) {
839 if ((ok = pop3_gettopid(sock, try_id, id, sizeof(id))) != 0)
842 try_nr = str_nr_last_in_list(&ctl->oldsaved, id);
847 if( try_nr != list_len -1 ) {
848 /* some messages inbetween have been deleted... */
852 for( add_id = 1<<30; add_id > try_id-1; add_id >>= 1 )
854 for( ; add_id; add_id >>= 1 ) {
856 if( try_id - add_id <= 1 ) {
863 if ((ok = pop3_gettopid(sock, try_id, id, sizeof(id))) != 0)
865 try_nr = str_nr_in_list(&ctl->oldsaved, id);
872 GT_("Messages inserted into list on server. Cannot handle this.\n"));
877 /* the first try_id messages are known -> copy them to the newsaved list */
878 for( num = first_nr; num < list_len; num++ )
880 struct idlist *newl = save_str(&ctl->newsaved,
881 str_from_nr_list(&ctl->oldsaved, num),
883 newl->val.status.num = num - first_nr + 1;
887 free_str_list(&ctl->oldsaved);
892 *newp = *countp - try_id;
896 static int pop3_getrange(int sock,
899 int *countp, int *newp, int *bytes)
900 /* get range of messages to be fetched */
903 char buf [POPBUFSIZE+1];
906 /* Ensure that the new list is properly empty */
907 ctl->newsaved = (struct idlist *)NULL;
910 /* Alain Knaff suggests this, but it's not RFC standard */
912 if ((ok = gen_transact(sock, "MBOX %s", folder)))
916 /* get the total message count */
917 gen_send(sock, "STAT");
918 ok = pop3_ok(sock, buf);
920 sscanf(buf,"%d %d", countp, bytes);
925 * Newer, RFC-1725/1939-conformant POP servers may not have the LAST
926 * command. We work as hard as possible to hide this, but it makes
927 * counting new messages intrinsically quadratic in the worst case.
931 /* if there are messages, and UIDL is desired, use UIDL
932 * also use UIDL if fetchall is unset */
933 if (*countp > 0 && (!ctl->fetchall || ctl->server.uidl))
938 /* should we do fast uidl this time? */
939 fastuidl = ctl->fastuidl;
940 if (*countp > 7 && /* linear search is better if there are few mails! */
941 !ctl->fetchall && /* with fetchall, all uids are required */
942 !ctl->flush && /* with flush, it is safer to disable fastuidl */
943 NUM_NONZERO (fastuidl))
948 dofastuidl = ctl->fastuidlcount != 0;
953 if (!ctl->server.uidl) {
954 gen_send(sock, "LAST");
955 ok = pop3_ok(sock, buf);
961 /* scan LAST reply */
962 if (sscanf(buf, "%d", &last) == 0)
964 report(stderr, GT_("protocol error\n"));
967 *newp = (*countp - last);
973 return(pop3_fastuidl( sock, ctl, *countp, newp));
974 /* grab the mailbox's UID list */
975 if ((ok = gen_transact(sock, "UIDL")) != 0)
977 /* don't worry, yet! do it the slow way */
978 if ((ok = pop3_slowuidl(sock, ctl, countp, newp)))
980 report(stderr, GT_("protocol error while fetching UIDLs\n"));
986 /* UIDL worked - parse reply */
990 while ((ok = gen_recv(sock, buf, sizeof(buf))) == PS_SUCCESS)
995 if (parseuid(buf, &unum, id, sizeof(id)) == PS_SUCCESS)
997 struct idlist *old, *newl;
999 newl = save_str(&ctl->newsaved, id, UID_UNSEEN);
1000 newl->val.status.num = unum;
1002 if ((old = str_in_list(&ctl->oldsaved, id, FALSE)))
1004 flag mark = old->val.status.mark;
1005 if (mark == UID_DELETED || mark == UID_EXPUNGED)
1007 /* XXX FIXME: switch 3 occurrences from
1008 * (int)unum or (unsigned int)unum to
1009 * remove the cast and use %lu - not now
1010 * though, time for new release */
1011 if (outlevel >= O_VERBOSE)
1012 report(stderr, GT_("id=%s (num=%d) was deleted, but is still present!\n"), id, (int)unum);
1013 /* just mark it as seen now! */
1014 old->val.status.mark = mark = UID_SEEN;
1016 newl->val.status.mark = mark;
1017 if (mark == UID_UNSEEN)
1020 if (outlevel >= O_DEBUG)
1021 report(stdout, GT_("%u is unseen\n"), (unsigned int)unum);
1027 if (outlevel >= O_DEBUG)
1028 report(stdout, GT_("%u is unseen\n"), (unsigned int)unum);
1029 /* add it to oldsaved also! In case, we do not
1030 * swap the lists (say, due to socket error),
1031 * the same mail will not be downloaded again.
1033 old = save_str(&ctl->oldsaved, id, UID_UNSEEN);
1035 /* save the number */
1036 old->val.status.num = unum;
1039 } /* multi-line loop for UIDL reply */
1047 static int pop3_getpartialsizes(int sock, int first, int last, int *sizes)
1048 /* capture the size of message #first */
1051 char buf [POPBUFSIZE+1];
1054 for (i = first; i <= last; i++) {
1055 gen_send(sock, "LIST %d", i);
1056 if ((ok = pop3_ok(sock, buf)) != 0)
1058 if (sscanf(buf, "%d %u", &num, &size) == 2) {
1060 sizes[i - first] = size;
1062 /* warn about possible attempt to induce buffer overrun
1064 * we expect server reply message number and requested
1065 * message number to match */
1066 report(stderr, "Warning: ignoring bogus data for message sizes returned by server.\n");
1072 static int pop3_getsizes(int sock, int count, int *sizes)
1073 /* capture the sizes of all messages */
1077 if ((ok = gen_transact(sock, "LIST")) != 0)
1081 char buf [POPBUFSIZE+1];
1083 while ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
1085 unsigned int num, size;
1089 else if (sscanf(buf, "%u %u", &num, &size) == 2) {
1090 if (num > 0 && num <= (unsigned)count)
1091 sizes[num - 1] = size;
1093 /* warn about possible attempt to induce buffer overrun */
1094 report(stderr, "Warning: ignoring bogus data for message sizes returned by server.\n");
1102 static int pop3_is_old(int sock, struct query *ctl, int num)
1103 /* is the given message old? */
1105 struct idlist *newl;
1107 return (num <= last);
1108 else if (dofastuidl)
1115 /* in fast uidl, we manipulate the old list only! */
1117 if ((newl = id_find(&ctl->oldsaved, num)))
1119 /* we already have the id! */
1120 return(newl->val.status.mark != UID_UNSEEN);
1123 /* get the uidl first! */
1124 if (pop3_getuidl(sock, num, id, sizeof(id)) != PS_SUCCESS)
1127 if ((newl = str_in_list(&ctl->oldsaved, id, FALSE))) {
1128 /* we already have the id! */
1129 newl->val.status.num = num;
1130 return(newl->val.status.mark != UID_UNSEEN);
1134 newl = save_str(&ctl->oldsaved, id, UID_UNSEEN);
1135 newl->val.status.num = num;
1139 return ((newl = id_find(&ctl->newsaved, num)) != NULL &&
1140 newl->val.status.mark != UID_UNSEEN);
1145 * We could use this to fetch headers only as we do for IMAP. The trouble
1146 * is that there's no way to fetch the body only. So the following RETR
1147 * would have to re-fetch the header. Enough messages have longer headers
1148 * than bodies to make this a net loss.
1150 static int pop_fetch_headers(int sock, struct query *ctl,int number,int *lenp)
1151 /* request headers of nth message */
1154 char buf[POPBUFSIZE+1];
1156 gen_send(sock, "TOP %d 0", number);
1157 if ((ok = pop3_ok(sock, buf)) != 0)
1160 *lenp = -1; /* we got sizes from the LIST response */
1166 static int pop3_fetch(int sock, struct query *ctl, int number, int *lenp)
1167 /* request nth message */
1170 char buf[POPBUFSIZE+1];
1174 * See http://www.demon.net/helpdesk/producthelp/mail/sdps-tech.html/
1175 * for a description of what we're parsing here.
1176 * -- updated 2006-02-22
1178 if (ctl->server.sdps)
1182 sdps_envfrom = (char *)NULL;
1183 sdps_envto = (char *)NULL;
1184 gen_send(sock, "*ENV %d", number);
1186 if (gen_recv(sock, buf, sizeof(buf)))
1191 switch (linecount) {
1193 /* No need to wrap envelope from address */
1194 /* FIXME: some parts of fetchmail don't handle null
1195 * envelope senders, so use <> to mark null sender
1196 * as a workaround. */
1197 if (strspn(buf, " \t") == strlen(buf))
1199 sdps_envfrom = xmalloc(strlen(buf)+1);
1200 strcpy(sdps_envfrom,buf);
1203 /* Wrap address with To: <> so nxtaddr() likes it */
1204 sdps_envto = xmalloc(strlen(buf)+7);
1205 sprintf(sdps_envto,"To: <%s>",buf);
1209 (!(buf[0] == '.' && (buf[1] == '\r' || buf[1] == '\n' || buf[1] == '\0')));
1213 #endif /* SDPS_ENABLE */
1216 * Though the POP RFCs don't document this fact, on almost every
1217 * POP3 server I know of messages are marked "seen" only at the
1218 * time the OK response to a RETR is issued.
1220 * This means we can use TOP to fetch the message without setting its
1221 * seen flag. This is good! It means that if the protocol exchange
1222 * craps out during the message, it will still be marked `unseen' on
1223 * the server. (Exception: in early 1999 SpryNet's POP3 servers were
1224 * reported to mark messages seen on a TOP fetch.)
1226 * However...*don't* do this if we're using keep to suppress deletion!
1227 * In that case, marking the seen flag is the only way to prevent the
1228 * message from being re-fetched on subsequent runs.
1230 * Also use RETR (that means no TOP, no peek) if fetchall is on.
1231 * This gives us a workaround for servers like usa.net's that bungle
1232 * TOP. It's pretty harmless because fetchall guarantees that any
1233 * message dropped by an interrupted RETR will be picked up on the
1234 * next poll of the site.
1236 * We take advantage here of the fact that, according to all the
1237 * POP RFCs, "if the number of lines requested by the POP3 client
1238 * is greater than than the number of lines in the body, then the
1239 * POP3 server sends the entire message.").
1241 * The line count passed (99999999) is the maximum value CompuServe will
1242 * accept; it's much lower than the natural value 2147483646 (the maximum
1243 * twos-complement signed 32-bit integer minus 1) */
1245 gen_send(sock, "RETR %d", number);
1247 gen_send(sock, "TOP %d 99999999", number);
1248 if ((ok = pop3_ok(sock, buf)) != 0)
1251 *lenp = -1; /* we got sizes from the LIST response */
1256 static void mark_uid_seen(struct query *ctl, int number)
1257 /* Tell the UID code we've seen this. */
1261 if ((sdp = id_find(&ctl->newsaved, number)))
1262 sdp->val.status.mark = UID_SEEN;
1263 /* mark it as seen in oldsaved also! In case, we do not swap the lists
1264 * (say, due to socket error), the same mail will not be downloaded
1267 if ((sdp = id_find(&ctl->oldsaved, number)))
1268 sdp->val.status.mark = UID_SEEN;
1271 static int pop3_delete(int sock, struct query *ctl, int number)
1272 /* delete a given message */
1275 mark_uid_seen(ctl, number);
1276 /* actually, mark for deletion -- doesn't happen until QUIT time */
1277 ok = gen_transact(sock, "DELE %d", number);
1278 if (ok != PS_SUCCESS)
1280 delete_str(dofastuidl ? &ctl->oldsaved : &ctl->newsaved, number);
1284 static int pop3_mark_seen(int sock, struct query *ctl, int number)
1285 /* mark a given message as seen */
1288 mark_uid_seen(ctl, number);
1292 static int pop3_logout(int sock, struct query *ctl)
1293 /* send logout command */
1299 * We used to do this in case the server marks messages deleted when seen.
1300 * (Yes, this has been reported, in the MercuryP/NLM server.
1301 * It's even legal under RFC 1939 (section 8) as a site policy.)
1302 * It interacted badly with UIDL, though. Thomas Zajic wrote:
1303 * "Running 'fetchmail -F -v' and checking the logs, I found out
1304 * that fetchmail did in fact flush my mailbox properly, but sent
1305 * a RSET just before sending QUIT to log off. This caused the
1306 * POP3 server to undo/forget about the previous DELEs, resetting
1307 * my mailbox to its original (ie. unflushed) state. The
1308 * ~/.fetchids file did get flushed though, so the next time
1309 * fetchmail was run it saw all the old messages as new ones ..."
1312 gen_transact(sock, "RSET");
1313 #endif /* __UNUSED__ */
1315 ok = gen_transact(sock, "QUIT");
1322 static const struct method pop3 =
1324 "POP3", /* Post Office Protocol v3 */
1325 "pop3", /* port for plain and TLS POP3 */
1326 "pop3s", /* port for SSL POP3 */
1327 FALSE, /* this is not a tagged protocol */
1328 TRUE, /* this uses a message delimiter */
1329 pop3_ok, /* parse command response */
1330 pop3_getauth, /* get authorization */
1331 pop3_getrange, /* query range of messages */
1332 pop3_getsizes, /* we can get a list of sizes */
1333 pop3_getpartialsizes, /* we can get the size of 1 mail */
1334 pop3_is_old, /* how do we tell a message is old? */
1335 pop3_fetch, /* request given message */
1336 NULL, /* no way to fetch body alone */
1337 NULL, /* no message trailer */
1338 pop3_delete, /* how to delete a message */
1339 pop3_mark_seen, /* how to mark a message as seen */
1340 NULL, /* no action at end of mailbox */
1341 pop3_logout, /* log out, we're done */
1342 FALSE, /* no, we can't re-poll */
1345 int doPOP3 (struct query *ctl)
1346 /* retrieve messages using POP3 */
1349 if (ctl->mailboxes->id) {
1350 fprintf(stderr,GT_("Option --folder is not supported with POP3\n"));
1355 return(do_protocol(ctl, &pop3));
1357 #endif /* POP3_ENABLE */
1359 /* pop3.c ends here */