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"
27 #endif /* OPIE_ENABLE */
33 #endif /* SDPS_ENABLE */
36 static char lastok[POPBUFSIZE+1];
37 #endif /* OPIE_ENABLE */
39 /* these variables are shared between the CAPA probe and the authenticator */
41 flag has_gssapi = FALSE;
42 #endif /* defined(GSSAPI) */
43 #if defined(KERBEROS_V4) || defined(KERBEROS_V5)
44 flag has_kerberos = FALSE;
45 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
46 static flag has_cram = FALSE;
49 #endif /* OPIE_ENABLE */
51 static flag has_ssl = FALSE;
52 #endif /* SSL_ENABLE */
57 static tSmbNtlmAuthRequest request;
58 static tSmbNtlmAuthChallenge challenge;
59 static tSmbNtlmAuthResponse response;
62 * NTLM support by Grant Edwards.
64 * Handle MS-Exchange NTLM authentication method. This is the same
65 * as the NTLM auth used by Samba for SMB related services. We just
66 * encode the packets in base64 instead of sending them out via a
69 * Much source (ntlm.h, smb*.c smb*.h) was borrowed from Samba.
72 static int do_pop3_ntlm(int sock, struct query *ctl)
77 gen_send(sock, "AUTH MSN");
79 if ((result = gen_recv(sock, msgbuf, sizeof msgbuf)))
85 buildSmbNtlmAuthRequest(&request,ctl->remotename,NULL);
87 if (outlevel >= O_DEBUG)
88 dumpSmbNtlmAuthRequest(stdout, &request);
90 memset(msgbuf,0,sizeof msgbuf);
91 to64frombits (msgbuf, (unsigned char*)&request, SmbLength(&request));
93 if (outlevel >= O_MONITOR)
94 report(stdout, "POP3> %s\n", msgbuf);
96 strcat(msgbuf,"\r\n");
97 SockWrite (sock, msgbuf, strlen (msgbuf));
99 if ((gen_recv(sock, msgbuf, sizeof msgbuf)))
102 len = from64tobits ((unsigned char*)&challenge, msgbuf, sizeof(msgbuf));
104 if (outlevel >= O_DEBUG)
105 dumpSmbNtlmAuthChallenge(stdout, &challenge);
107 buildSmbNtlmAuthResponse(&challenge, &response,ctl->remotename,ctl->password);
109 if (outlevel >= O_DEBUG)
110 dumpSmbNtlmAuthResponse(stdout, &response);
112 memset(msgbuf,0,sizeof msgbuf);
113 to64frombits (msgbuf, (unsigned char*)&response, SmbLength(&response));
115 if (outlevel >= O_MONITOR)
116 report(stdout, "POP3> %s\n", msgbuf);
118 strcat(msgbuf,"\r\n");
119 SockWrite (sock, msgbuf, strlen (msgbuf));
121 if ((result = gen_recv (sock, msgbuf, sizeof msgbuf)))
124 if (strstr (msgbuf, "OK"))
132 #define DOTLINE(s) (s[0] == '.' && (s[1]=='\r'||s[1]=='\n'||s[1]=='\0'))
134 static int pop3_ok (int sock, char *argbuf)
135 /* parse command response */
138 char buf [POPBUFSIZE+1];
141 if ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
143 if (*bufp == '+' || *bufp == '-')
148 while (isalpha((unsigned char)*bufp))
154 if (strcmp(buf,"+OK") == 0)
157 strcpy(lastok, bufp);
158 #endif /* OPIE_ENABLE */
161 else if (strncmp(buf,"-ERR", 4) == 0)
163 if (stage == STAGE_FETCH)
165 else if (stage > STAGE_GETAUTH)
168 * We're checking for "lock busy", "unable to lock",
169 * "already locked", "wait a few minutes" etc. here.
170 * This indicates that we have to wait for the server to
171 * unwedge itself before we can poll again.
173 * PS_LOCKBUSY check empirically verified with two recent
174 * versions of the Berkeley popper; QPOP (version 2.2) and
175 * QUALCOMM Pop server derived from UCB (version 2.1.4-R3)
176 * These are caught by the case-indifferent "lock" check.
177 * The "wait" catches "mail storage services unavailable,
178 * wait a few minutes and try again" on the InterMail server.
180 * If these aren't picked up on correctly, fetchmail will
181 * think there is an authentication failure and wedge the
182 * connection in order to prevent futile polls.
186 else if (strstr(bufp,"lock")
187 || strstr(bufp,"Lock")
188 || strstr(bufp,"LOCK")
189 || strstr(bufp,"wait")
190 /* these are blessed by RFC 2449 */
191 || strstr(bufp,"[IN-USE]")||strstr(bufp,"[LOGIN-DELAY]"))
193 else if ((strstr(bufp,"Service")
194 || strstr(bufp,"service"))
195 && (strstr(bufp,"unavailable")))
200 * We always want to pass the user lock-busy messages, because
201 * they're red flags. Other stuff (like AUTH failures on non-
202 * RFC1734 servers) only if we're debugging.
204 if (*bufp && (ok == PS_LOCKBUSY || outlevel >= O_MONITOR))
205 report(stderr, "%s\n", bufp);
219 static int capa_probe(int sock)
220 /* probe the capabilities of the remote server */
226 #endif /* defined(GSSAPI) */
227 #if defined(KERBEROS_V4) || defined(KERBEROS_V5)
228 has_kerberos = FALSE;
229 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
233 #endif /* OPIE_ENABLE */
235 ok = gen_transact(sock, "CAPA");
236 if (ok == PS_SUCCESS)
240 /* determine what authentication methods we have available */
241 while ((ok = gen_recv(sock, buffer, sizeof(buffer))) == 0)
246 if (strstr(buffer, "STLS"))
248 #endif /* SSL_ENABLE */
250 if (strstr(buffer, "GSSAPI"))
252 #endif /* defined(GSSAPI) */
253 #if defined(KERBEROS_V4)
254 if (strstr(buffer, "KERBEROS_V4"))
256 #endif /* defined(KERBEROS_V4) */
258 if (strstr(buffer, "X-OTP"))
260 #endif /* OPIE_ENABLE */
261 if (strstr(buffer, "CRAM-MD5"))
268 static void set_peek_capable(struct query *ctl)
270 /* we're peek-capable means that the use of TOP is enabled,
271 * see pop3_fetch for details - short story, we can use TOP if
272 * we have a means of reliably tracking which mail we need to
273 * refetch should the connection abort in the middle.
274 * fetchall forces RETR, as does keep without UIDL */
275 peek_capable = !ctl->fetchall && (!ctl->keep || ctl->server.uidl);
278 static int pop3_getauth(int sock, struct query *ctl, char *greeting)
279 /* apply for connection authorization */
286 #endif /* OPIE_ENABLE */
288 flag did_stls = FALSE;
289 #endif /* SSL_ENABLE */
293 #endif /* defined(GSSAPI) */
294 #if defined(KERBEROS_V4) || defined(KERBEROS_V5)
295 has_kerberos = FALSE;
296 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
300 #endif /* OPIE_ENABLE */
303 #endif /* SSL_ENABLE */
305 if (ctl->server.authenticate == A_SSH) {
311 * This needs to catch both demon.co.uk and demon.net.
312 * If we see either, and we're in multidrop mode, try to use
313 * the SDPS *ENV extension.
315 if (!(ctl->server.sdps) && MULTIDROP(ctl) && strstr(greeting, "demon."))
316 ctl->server.sdps = TRUE;
317 #endif /* SDPS_ENABLE */
319 /* MSN servers require the use of NTLM (MSN) authentication */
320 if (!strcasecmp(ctl->server.pollname, "pop3.email.msn.com") ||
321 ctl->server.authenticate == A_NTLM)
323 if (!do_pop3_ntlm(sock, ctl))
334 switch (ctl->server.protocol) {
337 /* CompuServe POP3 Servers as of 990730 want AUTH first for RPA */
338 if (strstr(ctl->remotename, "@compuserve.com"))
340 /* AUTH command should return a list of available mechanisms */
341 if (gen_transact(sock, "AUTH") == 0)
344 flag has_rpa = FALSE;
346 while ((ok = gen_recv(sock, buffer, sizeof(buffer))) == 0)
350 if (strncasecmp(buffer, "rpa", 3) == 0)
353 if (has_rpa && !POP3_auth_rpa(ctl->remotename,
354 ctl->password, sock))
360 #endif /* RPA_ENABLE */
363 * CAPA command may return a list including available
364 * authentication mechanisms. if it doesn't, no harm done, we
365 * just fall back to a plain login. Note that this code
366 * latches the server's authentication type, so that in daemon mode
367 * the CAPA check only needs to be done once at start of run.
369 * If CAPA fails, then force the authentication method to PASSORD
370 * and repoll immediately.
372 * These authentication methods are blessed by RFC1734,
373 * describing the POP3 AUTHentication command.
375 if ((ctl->server.authenticate == A_ANY) ||
376 (ctl->server.authenticate == A_GSSAPI) ||
377 (ctl->server.authenticate == A_KERBEROS_V4) ||
378 (ctl->server.authenticate == A_OTP) ||
379 (ctl->server.authenticate == A_CRAM_MD5))
381 if ((ok = capa_probe(sock)) != PS_SUCCESS)
382 /* we are in STAGE_GETAUTH! */
383 if (ok == PS_AUTHFAIL ||
384 /* Some servers directly close the socket. However, if we
385 * have already authenticated before, then a previous CAPA
386 * must have succeeded. In that case, treat this as a
387 * genuine socket error and do not change the auth method.
389 (ok == PS_SOCKET && !ctl->wehaveauthed))
391 ctl->server.authenticate = A_PASSWORD;
392 /* repoll immediately */
401 && (!ctl->sslproto || !strcmp(ctl->sslproto,"tls1")))
405 realhost = ctl->server.via ? ctl->server.via : ctl->server.pollname;
406 ok = gen_transact(sock, "STLS");
408 /* We use "tls1" instead of ctl->sslproto, as we want STLS,
409 * not other SSL protocols
411 if (ok == PS_SUCCESS &&
412 SSLOpen(sock,ctl->sslcert,ctl->sslkey,"tls1",ctl->sslcertck, ctl->sslcertpath,ctl->sslfingerprint,realhost,ctl->server.pollname) == -1)
414 if (!ctl->sslproto && !ctl->wehaveauthed)
416 ctl->sslproto = xstrdup("");
417 /* repoll immediately */
421 GT_("SSL connection failed.\n"));
427 * RFC 2595 says this:
429 * "Once TLS has been started, the client MUST discard cached
430 * information about server capabilities and SHOULD re-issue the
431 * CAPABILITY command. This is necessary to protect against
432 * man-in-the-middle attacks which alter the capabilities list prior
433 * to STARTTLS. The server MAY advertise different capabilities
438 #endif /* SSL_ENABLE */
441 * OK, we have an authentication type now.
443 #if defined(KERBEROS_V4)
445 * Servers doing KPOP have to go through a dummy login sequence
446 * rather than doing SASL.
450 ctl->server.service && (strcmp(ctl->server.service, KPOP_PORT)!=0)
451 #else /* INET6_ENABLE */
452 ctl->server.port != KPOP_PORT
453 #endif /* INET6_ENABLE */
454 && (ctl->server.authenticate == A_KERBEROS_V4
455 || ctl->server.authenticate == A_KERBEROS_V5
456 || ctl->server.authenticate == A_ANY))
458 ok = do_rfc1731(sock, "AUTH", ctl->server.truename);
459 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
462 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
466 (ctl->server.authenticate == A_GSSAPI ||
467 ctl->server.authenticate == A_ANY))
469 ok = do_gssauth(sock,"AUTH","pop",ctl->server.truename,ctl->remotename);
470 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
473 #endif /* defined(GSSAPI) */
477 (ctl->server.authenticate == A_OTP ||
478 ctl->server.authenticate == A_ANY))
480 ok = do_otp(sock, "AUTH", ctl);
481 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
484 #endif /* OPIE_ENABLE */
486 if (ctl->server.authenticate == A_CRAM_MD5 ||
487 (has_cram && ctl->server.authenticate == A_ANY))
489 ok = do_cram_md5(sock, "AUTH", ctl, NULL);
490 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
494 /* ordinary validation, no one-time password or RPA */
495 if ((ok = gen_transact(sock, "USER %s", ctl->remotename)))
499 /* see RFC1938: A One-Time Password System */
500 if ((challenge = strstr(lastok, "otp-"))) {
501 char response[OPIE_RESPONSE_MAX+1];
504 i = opiegenerator(challenge, !strcmp(ctl->password, "opie") ? "" : ctl->password, response);
505 if ((i == -2) && !run.poll_interval) {
506 char secret[OPIE_SECRET_MAX+1];
507 fprintf(stderr, GT_("Secret pass phrase: "));
508 if (opiereadpass(secret, sizeof(secret), 0))
509 i = opiegenerator(challenge, secret, response);
510 memset(secret, 0, sizeof(secret));
518 ok = gen_transact(sock, "PASS %s", response);
521 #endif /* OPIE_ENABLE */
523 strcpy(shroud, ctl->password);
524 ok = gen_transact(sock, "PASS %s", ctl->password);
527 /* this is for servers which claim to support TLS, but actually
529 if (did_stls && ok == PS_SOCKET && !ctl->sslproto && !ctl->wehaveauthed)
531 ctl->sslproto = xstrdup("");
532 /* repoll immediately */
539 /* build MD5 digest from greeting timestamp + password */
540 /* find start of timestamp */
541 for (start = greeting; *start != 0 && *start != '<'; start++)
545 GT_("Required APOP timestamp not found in greeting\n"));
549 /* find end of timestamp */
550 for (end = start; *end != 0 && *end != '>'; end++)
552 if (*end == 0 || end == start + 1) {
554 GT_("Timestamp syntax error in greeting\n"));
560 /* copy timestamp and password into digestion buffer */
561 xalloca(msg, char *, (end-start+1) + strlen(ctl->password) + 1);
563 strcat(msg,ctl->password);
565 strcpy(ctl->digest, MD5Digest((unsigned char *)msg));
567 ok = gen_transact(sock, "APOP %s %s", ctl->remotename, ctl->digest);
571 if ((ok = gen_transact(sock,"USER %s", ctl->remotename)) == 0)
572 ok = gen_transact(sock, "RPOP %s", ctl->password);
576 report(stderr, GT_("Undefined protocol request in POP3_auth\n"));
582 /* maybe we detected a lock-busy condition? */
583 if (ok == PS_LOCKBUSY)
584 report(stderr, GT_("lock busy! Is another session active?\n"));
589 /* Disable the sleep. Based on patch by Brian Candler 2004-04-19/2004-11-08,
590 * accepted by Matthias Andree.
592 * Rationale: the server must have locked the spool before returning +OK;
593 * this sleep just wastes time and hence, for modem and GSM CSD users, money. */
596 * Empirical experience shows some server/OS combinations
597 * may need a brief pause even after any lockfiles on the
598 * server are released, to give the server time to finish
599 * copying back very large mailfolders from the temp-file...
600 * this is only ever an issue with extremely large mailboxes.
602 sleep(3); /* to be _really_ safe, probably need sleep(5)! */
605 set_peek_capable(ctl);
611 static int pop3_gettopid(int sock, int num , char *id, size_t idsize)
615 char buf [POPBUFSIZE+1];
616 snprintf(buf, sizeof(buf), "TOP %d 1", num);
617 if ((ok = gen_transact(sock, buf )) != 0)
620 while ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
624 if (!got_it && 0 == strncasecmp("Message-Id:", buf, 11)) {
626 p += strspn(p, POSIX_space);
627 p = strtok(p, POSIX_space);
628 strlcpy(id, p, idsize);
634 /** Parse destructively the UID response (leading +OK must have been
635 * stripped off) in buf, store the number in gotnum, and store the ID
636 * into the caller-provided buffer "id" of size "idsize".
637 * Returns PS_SUCCESS or PS_PROTOCOL for failure. */
638 static int parseuid(char *buf, unsigned long *gotnum, char *id, size_t idsize)
642 i = strtok(buf, POSIX_space);
644 *gotnum = strtoul(i, &j, 10);
645 if (*j != '\0' || j == i || errno) {
646 report(stderr, GT_("Cannot handle UIDL response from upstream server.\n"));
649 i = strtok(NULL, POSIX_space);
650 strlcpy(id, i, idsize);
654 static int pop3_getuidl(int sock, int num , char *id, size_t idsize)
657 char buf [POPBUFSIZE+1];
658 unsigned long gotnum;
660 gen_send(sock, "UIDL %d", num);
661 if ((ok = pop3_ok(sock, buf)) != 0)
663 if ((ok = parseuid(buf, &gotnum, id, idsize)))
666 report(stderr, GT_("Server responded with UID for wrong message.\n"));
672 static int pop3_fastuidl( int sock, struct query *ctl, unsigned int count, int *newp)
675 unsigned int first_nr, last_nr, try_nr;
680 while (first_nr < last_nr - 1)
684 try_nr = (first_nr + last_nr) / 2;
685 if ((ok = pop3_getuidl(sock, try_nr, id, sizeof(id))) != 0)
687 if ((new = str_in_list(&ctl->oldsaved, id, FALSE)))
689 flag mark = new->val.status.mark;
690 if (mark == UID_DELETED || mark == UID_EXPUNGED)
692 if (outlevel >= O_VERBOSE)
693 report(stderr, GT_("id=%s (num=%d) was deleted, but is still present!\n"), id, try_nr);
694 /* just mark it as seen now! */
695 new->val.status.mark = mark = UID_SEEN;
698 /* narrow the search region! */
699 if (mark == UID_UNSEEN)
701 if (outlevel >= O_DEBUG)
702 report(stdout, GT_("%u is unseen\n"), try_nr);
708 /* save the number */
709 new->val.status.num = try_nr;
713 if (outlevel >= O_DEBUG)
714 report(stdout, GT_("%u is unseen\n"), try_nr);
718 new = save_str(&ctl->oldsaved, id, UID_UNSEEN);
719 new->val.status.num = try_nr;
722 if (outlevel >= O_DEBUG && last_nr <= count)
723 report(stdout, GT_("%u is first unseen\n"), last_nr);
726 *newp = count - first_nr;
731 static int pop3_slowuidl( int sock, struct query *ctl, int *countp, int *newp)
733 /* This approach tries to get the message headers from the
734 * remote hosts and compares the message-id to the already known
736 * + if the first message containes a new id, all messages on
737 * the server will be new
738 * + if the first is known, try to estimate the last known message
739 * on the server and check. If this works you know the total number
740 * of messages to get.
741 * + Otherwise run a binary search to determine the last known message
743 int ok, nolinear = 0;
744 int first_nr, list_len, try_id, try_nr, add_id;
748 if ((ok = pop3_gettopid(sock, 1, id, sizeof(id))) != 0)
751 if( ( first_nr = str_nr_in_list(&ctl->oldsaved, id) ) == -1 ) {
752 /* the first message is unknown -> all messages are new */
757 /* check where we expect the latest known message */
758 list_len = count_list( &ctl->oldsaved );
759 try_id = list_len - first_nr; /* -1 + 1 */
761 if( try_id <= *countp ) {
762 if ((ok = pop3_gettopid(sock, try_id, id, sizeof(id))) != 0)
765 try_nr = str_nr_last_in_list(&ctl->oldsaved, id);
770 if( try_nr != list_len -1 ) {
771 /* some messages inbetween have been deleted... */
775 for( add_id = 1<<30; add_id > try_id-1; add_id >>= 1 )
777 for( ; add_id; add_id >>= 1 ) {
779 if( try_id - add_id <= 1 ) {
786 if ((ok = pop3_gettopid(sock, try_id, id, sizeof(id))) != 0)
788 try_nr = str_nr_in_list(&ctl->oldsaved, id);
795 GT_("Messages inserted into list on server. Cannot handle this.\n"));
800 /* the first try_id messages are known -> copy them to the newsaved list */
801 for( num = first_nr; num < list_len; num++ )
803 struct idlist *new = save_str(&ctl->newsaved,
804 str_from_nr_list(&ctl->oldsaved, num),
806 new->val.status.num = num - first_nr + 1;
810 free_str_list(&ctl->oldsaved);
815 *newp = *countp - try_id;
819 static int pop3_getrange(int sock,
822 int *countp, int *newp, int *bytes)
823 /* get range of messages to be fetched */
826 char buf [POPBUFSIZE+1];
828 /* Ensure that the new list is properly empty */
829 ctl->newsaved = (struct idlist *)NULL;
832 /* Alain Knaff suggests this, but it's not RFC standard */
834 if ((ok = gen_transact(sock, "MBOX %s", folder)))
838 /* get the total message count */
839 gen_send(sock, "STAT");
840 ok = pop3_ok(sock, buf);
842 sscanf(buf,"%d %d", countp, bytes);
847 * Newer, RFC-1725-conformant POP servers may not have the LAST command.
848 * We work as hard as possible to hide this ugliness, but it makes
849 * counting new messages intrinsically quadratic in the worst case.
853 if (*countp > 0 && !ctl->fetchall)
858 /* should we do fast uidl this time? */
859 fastuidl = ctl->fastuidl;
860 if (*countp > 7 && /* linear search is better if there are few mails! */
861 !ctl->flush && /* with flush, it is safer to disable fastuidl */
862 NUM_NONZERO (fastuidl))
867 dofastuidl = ctl->fastuidlcount != 0;
872 if (!ctl->server.uidl) {
873 gen_send(sock, "LAST");
874 ok = pop3_ok(sock, buf);
879 if (sscanf(buf, "%d", &last) == 0)
881 report(stderr, GT_("protocol error\n"));
884 *newp = (*countp - last);
889 return(pop3_fastuidl( sock, ctl, *countp, newp));
890 /* grab the mailbox's UID list */
891 if ((ok = gen_transact(sock, "UIDL")) != 0)
893 /* don't worry, yet! do it the slow way */
894 if ((ok = pop3_slowuidl(sock, ctl, countp, newp)))
896 report(stderr, GT_("protocol error while fetching UIDLs\n"));
905 while ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
910 if (parseuid(buf, &unum, id, sizeof(id)) == PS_SUCCESS)
912 struct idlist *old, *new;
914 new = save_str(&ctl->newsaved, id, UID_UNSEEN);
915 new->val.status.num = unum;
917 if ((old = str_in_list(&ctl->oldsaved, id, FALSE)))
919 flag mark = old->val.status.mark;
920 if (mark == UID_DELETED || mark == UID_EXPUNGED)
922 /* XXX FIXME: switch 3 occurrences from
923 * (int)unum or (unsigned int)unum to
924 * remove the cast and use %lu - not now
925 * though, time for new release */
926 if (outlevel >= O_VERBOSE)
927 report(stderr, GT_("id=%s (num=%d) was deleted, but is still present!\n"), id, (int)unum);
928 /* just mark it as seen now! */
929 old->val.status.mark = mark = UID_SEEN;
931 new->val.status.mark = mark;
932 if (mark == UID_UNSEEN)
935 if (outlevel >= O_DEBUG)
936 report(stdout, GT_("%u is unseen\n"), (unsigned int)unum);
942 if (outlevel >= O_DEBUG)
943 report(stdout, GT_("%u is unseen\n"), (unsigned int)unum);
944 /* add it to oldsaved also! In case, we do not
945 * swap the lists (say, due to socket error),
946 * the same mail will not be downloaded again.
948 old = save_str(&ctl->oldsaved, id, UID_UNSEEN);
949 old->val.status.num = unum;
960 static int pop3_getpartialsizes(int sock, int first, int last, int *sizes)
961 /* capture the size of message #first */
964 char buf [POPBUFSIZE+1];
965 unsigned int num, size;
967 for (i = first; i <= last; i++) {
968 gen_send(sock, "LIST %d", i);
969 if ((ok = pop3_ok(sock, buf)) != 0)
971 if (sscanf(buf, "%u %u", &num, &size) == 2) {
973 sizes[i - first] = size;
975 /* warn about possible attempt to induce buffer overrun
977 * we expect server reply message number and requested
978 * message number to match */
979 report(stderr, "Warning: ignoring bogus data for message sizes returned by server.\n");
985 static int pop3_getsizes(int sock, int count, int *sizes)
986 /* capture the sizes of all messages */
990 if ((ok = gen_transact(sock, "LIST")) != 0)
994 char buf [POPBUFSIZE+1];
996 while ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
998 unsigned int num, size;
1002 else if (sscanf(buf, "%u %u", &num, &size) == 2) {
1003 if (num > 0 && num <= count)
1004 sizes[num - 1] = size;
1006 /* warn about possible attempt to induce buffer overrun */
1007 report(stderr, "Warning: ignoring bogus data for message sizes returned by server.\n");
1015 static int pop3_is_old(int sock, struct query *ctl, int num)
1016 /* is the given message old? */
1020 return (num <= last);
1021 else if (dofastuidl)
1028 /* in fast uidl, we manipulate the old list only! */
1030 if ((new = id_find(&ctl->oldsaved, num)))
1032 /* we already have the id! */
1033 return(new->val.status.mark != UID_UNSEEN);
1036 /* get the uidl first! */
1037 if (pop3_getuidl(sock, num, id, sizeof(id)) != PS_SUCCESS)
1040 if ((new = str_in_list(&ctl->oldsaved, id, FALSE))) {
1041 /* we already have the id! */
1042 new->val.status.num = num;
1043 return(new->val.status.mark != UID_UNSEEN);
1047 new = save_str(&ctl->oldsaved, id, UID_UNSEEN);
1048 new->val.status.num = num;
1052 return ((new = id_find(&ctl->newsaved, num)) != NULL &&
1053 new->val.status.mark != UID_UNSEEN);
1058 * We could use this to fetch headers only as we do for IMAP. The trouble
1059 * is that there's no way to fetch the body only. So the following RETR
1060 * would have to re-fetch the header. Enough messages have longer headers
1061 * than bodies to make this a net loss.
1063 static int pop_fetch_headers(int sock, struct query *ctl,int number,int *lenp)
1064 /* request headers of nth message */
1067 char buf[POPBUFSIZE+1];
1069 gen_send(sock, "TOP %d 0", number);
1070 if ((ok = pop3_ok(sock, buf)) != 0)
1073 *lenp = -1; /* we got sizes from the LIST response */
1079 static int pop3_fetch(int sock, struct query *ctl, int number, int *lenp)
1080 /* request nth message */
1083 char buf[POPBUFSIZE+1];
1087 * See http://www.demon.net/services/mail/sdps-tech.html
1088 * for a description of what we're parsing here.
1090 if (ctl->server.sdps)
1094 sdps_envfrom = (char *)NULL;
1095 sdps_envto = (char *)NULL;
1096 gen_send(sock, "*ENV %d", number);
1098 if (gen_recv(sock, buf, sizeof(buf)))
1103 switch (linecount) {
1105 /* No need to wrap envelope from address */
1106 sdps_envfrom = xmalloc(strlen(buf)+1);
1107 strcpy(sdps_envfrom,buf);
1110 /* Wrap address with To: <> so nxtaddr() likes it */
1111 sdps_envto = xmalloc(strlen(buf)+7);
1112 sprintf(sdps_envto,"To: <%s>",buf);
1116 (!(buf[0] == '.' && (buf[1] == '\r' || buf[1] == '\n' || buf[1] == '\0')));
1118 #endif /* SDPS_ENABLE */
1121 * Though the POP RFCs don't document this fact, on almost every
1122 * POP3 server I know of messages are marked "seen" only at the
1123 * time the OK response to a RETR is issued.
1125 * This means we can use TOP to fetch the message without setting its
1126 * seen flag. This is good! It means that if the protocol exchange
1127 * craps out during the message, it will still be marked `unseen' on
1128 * the server. (Exception: in early 1999 SpryNet's POP3 servers were
1129 * reported to mark messages seen on a TOP fetch.)
1131 * However...*don't* do this if we're using keep to suppress deletion!
1132 * In that case, marking the seen flag is the only way to prevent the
1133 * message from being re-fetched on subsequent runs.
1135 * Also use RETR (that means no TOP, no peek) if fetchall is on.
1136 * This gives us a workaround for servers like usa.net's that bungle
1137 * TOP. It's pretty harmless because fetchall guarantees that any
1138 * message dropped by an interrupted RETR will be picked up on the
1139 * next poll of the site.
1141 * We take advantage here of the fact that, according to all the
1142 * POP RFCs, "if the number of lines requested by the POP3 client
1143 * is greater than than the number of lines in the body, then the
1144 * POP3 server sends the entire message.").
1146 * The line count passed (99999999) is the maximum value CompuServe will
1147 * accept; it's much lower than the natural value 2147483646 (the maximum
1148 * twos-complement signed 32-bit integer minus 1) */
1150 gen_send(sock, "RETR %d", number);
1152 gen_send(sock, "TOP %d 99999999", number);
1153 if ((ok = pop3_ok(sock, buf)) != 0)
1156 *lenp = -1; /* we got sizes from the LIST response */
1161 static void mark_uid_seen(struct query *ctl, int number)
1162 /* Tell the UID code we've seen this. */
1166 if ((sdp = id_find(&ctl->newsaved, number)))
1167 sdp->val.status.mark = UID_SEEN;
1168 /* mark it as seen in oldsaved also! In case, we do not swap the lists
1169 * (say, due to socket error), the same mail will not be downloaded
1172 if ((sdp = id_find(&ctl->oldsaved, number)))
1173 sdp->val.status.mark = UID_SEEN;
1176 static int pop3_delete(int sock, struct query *ctl, int number)
1177 /* delete a given message */
1180 mark_uid_seen(ctl, number);
1181 /* actually, mark for deletion -- doesn't happen until QUIT time */
1182 ok = gen_transact(sock, "DELE %d", number);
1183 if (ok != PS_SUCCESS)
1185 delete_str(dofastuidl ? &ctl->oldsaved : &ctl->newsaved, number);
1189 static int pop3_mark_seen(int sock, struct query *ctl, int number)
1190 /* mark a given message as seen */
1192 mark_uid_seen(ctl, number);
1196 static int pop3_logout(int sock, struct query *ctl)
1197 /* send logout command */
1203 * We used to do this in case the server marks messages deleted when seen.
1204 * (Yes, this has been reported, in the MercuryP/NLM server.
1205 * It's even legal under RFC 1939 (section 8) as a site policy.)
1206 * It interacted badly with UIDL, though. Thomas Zajic wrote:
1207 * "Running 'fetchmail -F -v' and checking the logs, I found out
1208 * that fetchmail did in fact flush my mailbox properly, but sent
1209 * a RSET just before sending QUIT to log off. This caused the
1210 * POP3 server to undo/forget about the previous DELEs, resetting
1211 * my mailbox to its original (ie. unflushed) state. The
1212 * ~/.fetchids file did get flushed though, so the next time
1213 * fetchmail was run it saw all the old messages as new ones ..."
1216 gen_transact(sock, "RSET");
1217 #endif /* __UNUSED__ */
1219 ok = gen_transact(sock, "QUIT");
1226 static const struct method pop3 =
1228 "POP3", /* Post Office Protocol v3 */
1230 "pop3", /* standard POP3 port */
1231 "pop3s", /* ssl POP3 port */
1232 #else /* INET6_ENABLE */
1233 110, /* standard POP3 port */
1234 995, /* ssl POP3 port */
1235 #endif /* INET6_ENABLE */
1236 FALSE, /* this is not a tagged protocol */
1237 TRUE, /* this uses a message delimiter */
1238 pop3_ok, /* parse command response */
1239 pop3_getauth, /* get authorization */
1240 pop3_getrange, /* query range of messages */
1241 pop3_getsizes, /* we can get a list of sizes */
1242 pop3_getpartialsizes, /* we can get the size of 1 mail */
1243 pop3_is_old, /* how do we tell a message is old? */
1244 pop3_fetch, /* request given message */
1245 NULL, /* no way to fetch body alone */
1246 NULL, /* no message trailer */
1247 pop3_delete, /* how to delete a message */
1248 pop3_mark_seen, /* how to mark a message as seen */
1249 pop3_logout, /* log out, we're done */
1250 FALSE, /* no, we can't re-poll */
1253 int doPOP3 (struct query *ctl)
1254 /* retrieve messages using POP3 */
1257 if (ctl->mailboxes->id) {
1258 fprintf(stderr,GT_("Option --remote is not supported with POP3\n"));
1262 set_peek_capable(ctl); /* XXX FIXME: is this needed or do we always
1263 call this from pop3_getauth anyways? */
1264 return(do_protocol(ctl, &pop3));
1266 #endif /* POP3_ENABLE */
1268 /* pop3.c ends here */