1 /*
2 * pop3.c -- POP3 protocol methods
3 *
4 * Copyright 1998 by Eric S. Raymond.
5 * For license terms, see the file COPYING in this directory.
6 */
7
8 #include "config.h"
9
10 #ifdef POP3_ENABLE
11 #include <stdio.h>
12 #include <string.h>
13 #include <ctype.h>
14 #if defined(HAVE_UNISTD_H)
15 #include <unistd.h>
16 #endif
17 #if defined(STDC_HEADERS)
18 #include <stdlib.h>
19 #endif
20 #include <errno.h>
21
22 #include "fetchmail.h"
23 #include "socket.h"
24 #include "i18n.h"
25 #include "uid_db.h"
26
27 #ifdef OPIE_ENABLE
28 #ifdef __cplusplus
29 extern "C" {
30 #endif
31 #include <opie.h>
32 #ifdef __cplusplus
33 }
34 #endif
35 #endif /* OPIE_ENABLE */
36
37 /* global variables: please reinitialize them explicitly for proper
38 * working in daemon mode */
39
40 /* TODO: session variables to be initialized before server greeting */
41 #ifdef OPIE_ENABLE
42 static char lastok[POPBUFSIZE+1];
43 #endif /* OPIE_ENABLE */
44
45 /* session variables initialized in capa_probe() or pop3_getauth() */
46 /* some of these will not be accessed depending on fetchmail's
47 * compile-time configuration */
48 static flag done_capa = FALSE;
49 static flag has_gssapi = FALSE;
50 static flag has_kerberos = FALSE;
51 static flag has_cram = FALSE;
52 static flag has_otp = FALSE;
53 static flag has_ntlm = FALSE;
54 static flag has_stls = FALSE;
55
clear_sessiondata(void)56 static void clear_sessiondata(void) {
57 /* must match defaults above */
58 #ifdef OPIE_ENABLE
59 memset(lastok, 0, sizeof(lastok));
60 #endif
61 done_capa = FALSE;
62 has_gssapi = FALSE;
63 has_kerberos = FALSE;
64 has_cram = FALSE;
65 has_otp = FALSE;
66 has_ntlm = FALSE;
67 has_stls = FALSE;
68 }
69
70 /* mailbox variables initialized in pop3_getrange() */
71 static int last;
72
73 /* mail variables initialized in pop3_fetch() */
74 #ifdef SDPS_ENABLE
75 char *sdps_envfrom;
76 char *sdps_envto;
77 #endif /* SDPS_ENABLE */
78
79 #ifdef NTLM_ENABLE
80 #include "ntlm.h"
81
82 /*
83 * NTLM support by Grant Edwards.
84 *
85 * Handle MS-Exchange NTLM authentication method. This is the same
86 * as the NTLM auth used by Samba for SMB related services. We just
87 * encode the packets in base64 instead of sending them out via a
88 * network interface.
89 *
90 * Much source (ntlm.h, smb*.c smb*.h) was borrowed from Samba.
91 */
92
do_pop3_ntlm(int sock,struct query * ctl,int msn_instead)93 static int do_pop3_ntlm(int sock, struct query *ctl,
94 int msn_instead /** if true, send AUTH MSN, else send AUTH NTLM */)
95 {
96 char msgbuf[POPBUFSIZE+1];
97 int result;
98
99 gen_send(sock, msn_instead ? "AUTH MSN" : "AUTH NTLM");
100
101 if ((result = ntlm_helper(sock, ctl, "POP3")))
102 return result;
103
104 if ((result = gen_recv (sock, msgbuf, sizeof msgbuf)))
105 return result;
106
107 if (strstr (msgbuf, "OK"))
108 return PS_SUCCESS;
109 else
110 return PS_AUTHFAIL;
111 }
112 #endif /* NTLM */
113
114
115 #define DOTLINE(s) (s[0] == '.' && (s[1]=='\r'||s[1]=='\n'||s[1]=='\0'))
116
pop3_setup(struct query * ctl)117 static int pop3_setup(struct query *ctl)
118 {
119 (void)ctl;
120 clear_sessiondata();
121 return PS_SUCCESS;
122 }
123
pop3_cleanup(struct query * ctl)124 static int pop3_cleanup(struct query *ctl)
125 {
126 (void)ctl;
127 clear_sessiondata();
128 return PS_SUCCESS;
129 }
130
pop3_ok(int sock,char * argbuf)131 static int pop3_ok (int sock, char *argbuf)
132 /* parse command response */
133 {
134 int ok;
135 char buf [POPBUFSIZE+1];
136 char *bufp;
137
138 if ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
139 { bufp = buf;
140 if (*bufp == '+' || *bufp == '-')
141 bufp++;
142 else
143 return(PS_PROTOCOL);
144
145 while (isalpha((unsigned char)*bufp))
146 bufp++;
147
148 if (*bufp)
149 *(bufp++) = '\0';
150
151 if (strcmp(buf,"+OK") == 0)
152 {
153 #ifdef OPIE_ENABLE
154 strlcpy(lastok, bufp, sizeof(lastok));
155 #endif /* OPIE_ENABLE */
156 ok = 0;
157 }
158 else if (strncmp(buf,"-ERR", 4) == 0)
159 {
160 if (stage == STAGE_FETCH)
161 ok = PS_TRANSIENT;
162 else if (stage > STAGE_GETAUTH)
163 ok = PS_PROTOCOL;
164 /*
165 * We're checking for "lock busy", "unable to lock",
166 * "already locked", "wait a few minutes" etc. here.
167 * This indicates that we have to wait for the server to
168 * unwedge itself before we can poll again.
169 *
170 * PS_LOCKBUSY check empirically verified with two recent
171 * versions of the Berkeley popper; QPOP (version 2.2) and
172 * QUALCOMM Pop server derived from UCB (version 2.1.4-R3)
173 * These are caught by the case-indifferent "lock" check.
174 * The "wait" catches "mail storage services unavailable,
175 * wait a few minutes and try again" on the InterMail server.
176 *
177 * If these aren't picked up on correctly, fetchmail will
178 * think there is an authentication failure and wedge the
179 * connection in order to prevent futile polls.
180 *
181 * Gad, what a kluge.
182 */
183 else if (strstr(bufp,"lock")
184 || strstr(bufp,"Lock")
185 || strstr(bufp,"LOCK")
186 || strstr(bufp,"wait")
187 /* these are blessed by RFC 2449 */
188 || strstr(bufp,"[IN-USE]")||strstr(bufp,"[LOGIN-DELAY]"))
189 ok = PS_LOCKBUSY;
190 else if ((strstr(bufp,"Service")
191 || strstr(bufp,"service"))
192 && (strstr(bufp,"unavailable")))
193 ok = PS_SERVBUSY;
194 else
195 ok = PS_AUTHFAIL;
196 /*
197 * We always want to pass the user lock-busy messages, because
198 * they're red flags. Other stuff (like AUTH failures on non-
199 * RFC1734 servers) only if we're debugging.
200 */
201 if (*bufp && (ok == PS_LOCKBUSY || outlevel >= O_MONITOR))
202 report(stderr, "%s\n", bufp);
203 }
204 else
205 ok = PS_PROTOCOL;
206
207 #if POPBUFSIZE > MSGBUFSIZE
208 #error "POPBUFSIZE must not be larger than MSGBUFSIZE"
209 #endif
210 if (argbuf != NULL)
211 strcpy(argbuf,bufp);
212 }
213
214 return(ok);
215 }
216
217
218
capa_probe(int sock)219 static int capa_probe(int sock)
220 /* probe the capabilities of the remote server */
221 {
222 int ok;
223
224 if (done_capa) {
225 return PS_SUCCESS;
226 }
227 #if defined(GSSAPI)
228 has_gssapi = FALSE;
229 #endif /* defined(GSSAPI) */
230 #if defined(KERBEROS_V4) || defined(KERBEROS_V5)
231 has_kerberos = FALSE;
232 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
233 has_cram = FALSE;
234 #ifdef OPIE_ENABLE
235 has_otp = FALSE;
236 #endif /* OPIE_ENABLE */
237 #ifdef NTLM_ENABLE
238 has_ntlm = FALSE;
239 #endif /* NTLM_ENABLE */
240
241 ok = gen_transact(sock, "CAPA");
242 if (ok == PS_SUCCESS)
243 {
244 char buffer[64];
245 char *cp;
246
247 /* determine what authentication methods we have available */
248 while ((ok = gen_recv(sock, buffer, sizeof(buffer))) == 0)
249 {
250 if (DOTLINE(buffer))
251 break;
252
253 for (cp = buffer; *cp; cp++) *cp = toupper((unsigned char)*cp);
254
255 #ifdef SSL_ENABLE
256 if (strstr(buffer, "STLS"))
257 has_stls = TRUE;
258 #endif /* SSL_ENABLE */
259
260 #if defined(GSSAPI)
261 if (strstr(buffer, "GSSAPI"))
262 has_gssapi = TRUE;
263 #endif /* defined(GSSAPI) */
264
265 #if defined(KERBEROS_V4)
266 if (strstr(buffer, "KERBEROS_V4"))
267 has_kerberos = TRUE;
268 #endif /* defined(KERBEROS_V4) */
269
270 #ifdef OPIE_ENABLE
271 if (strstr(buffer, "X-OTP"))
272 has_otp = TRUE;
273 #endif /* OPIE_ENABLE */
274
275 #ifdef NTLM_ENABLE
276 if (strstr(buffer, "NTLM"))
277 has_ntlm = TRUE;
278 #endif /* NTLM_ENABLE */
279
280 if (strstr(buffer, "CRAM-MD5"))
281 has_cram = TRUE;
282 }
283 }
284 done_capa = TRUE;
285 return(ok);
286 }
287
set_peek_capable(struct query * ctl)288 static void set_peek_capable(struct query *ctl)
289 {
290 /* we're peek-capable means that the use of TOP is enabled,
291 * see pop3_fetch for details - short story, we can use TOP if
292 * we have a means of reliably tracking which mail we need to
293 * refetch should the connection abort in the middle.
294 * fetchall forces RETR, as does keep without UIDL */
295 peek_capable = !ctl->fetchall && (!ctl->keep || ctl->server.uidl);
296 }
297
pop3_getauth(int sock,struct query * ctl,char * greeting)298 static int pop3_getauth(int sock, struct query *ctl, char *greeting)
299 /* apply for connection authorization */
300 {
301 int ok;
302 char *start,*end;
303 char *msg;
304 #ifdef OPIE_ENABLE
305 char *challenge;
306 #endif /* OPIE_ENABLE */
307 #ifdef SSL_ENABLE
308 flag connection_may_have_tls_errors = FALSE;
309 char *commonname;
310 #endif /* SSL_ENABLE */
311
312 /* Set this up before authentication quits early. */
313 set_peek_capable(ctl);
314
315 /* Hack: allow user to force RETR. */
316 if (peek_capable && getenv("FETCHMAIL_POP3_FORCE_RETR")) {
317 peek_capable = 0;
318 }
319
320 /*
321 * The "Maillennium POP3/PROXY server" deliberately truncates
322 * TOP replies after c. 64 or 80 kByte (we have varying reports), so
323 * disable TOP. Comcast once spewed marketing babble to the extent
324 * of protecting Outlook -- pretty overzealous to break a protocol
325 * for that that Microsoft could have read, too. Comcast aren't
326 * alone in using this software though.
327 * <http://lists.ccil.org/pipermail/fetchmail-friends/2004-April/008523.html>
328 * (Thanks to Ed Wilts for reminding me of that.)
329 *
330 * The warning is printed once per server, until fetchmail exits.
331 * It will be suppressed when --fetchall or other circumstances make
332 * us use RETR anyhow.
333 *
334 * Matthias Andree
335 */
336 if (peek_capable && strstr(greeting, "Maillennium POP3")) {
337 if ((ctl->server.workarounds & WKA_TOP) == 0) {
338 report(stdout, GT_("Warning: \"Maillennium POP3\" found, using RETR command instead of TOP.\n"));
339 ctl->server.workarounds |= WKA_TOP;
340 }
341 peek_capable = 0;
342 }
343
344 #ifdef SDPS_ENABLE
345 /*
346 * This needs to catch both demon.co.uk and demon.net.
347 * If we see either, and we're in multidrop mode, try to use
348 * the SDPS *ENV extension.
349 */
350 if (!(ctl->server.sdps) && MULTIDROP(ctl) && strstr(greeting, "demon."))
351 ctl->server.sdps = TRUE;
352 #endif /* SDPS_ENABLE */
353
354 switch (ctl->server.protocol) {
355 case P_POP3:
356 /*
357 * CAPA command may return a list including available
358 * authentication mechanisms and STLS capability.
359 *
360 * If it doesn't, no harm done, we just fall back to a plain
361 * login -- if the user allows it.
362 *
363 * Note that this code latches the server's authentication type,
364 * so that in daemon mode the CAPA check only needs to be done
365 * once at start of run.
366 *
367 * If CAPA fails, then force the authentication method to
368 * PASSWORD, switch off opportunistic and repoll immediately.
369 * If TLS is mandatory, fail up front.
370 */
371 if ((ctl->server.authenticate == A_ANY) ||
372 (ctl->server.authenticate == A_GSSAPI) ||
373 (ctl->server.authenticate == A_KERBEROS_V4) ||
374 (ctl->server.authenticate == A_KERBEROS_V5) ||
375 (ctl->server.authenticate == A_OTP) ||
376 (ctl->server.authenticate == A_CRAM_MD5) ||
377 maybe_starttls(ctl))
378 {
379 if ((ok = capa_probe(sock)) != PS_SUCCESS)
380 /* we are in STAGE_GETAUTH => failure is PS_AUTHFAIL! */
381 if (ok == PS_AUTHFAIL ||
382 /* Some servers directly close the socket. However, if we
383 * have already authenticated before, then a previous CAPA
384 * must have succeeded. In that case, treat this as a
385 * genuine socket error and do not change the auth method.
386 */
387 (ok == PS_SOCKET && !ctl->wehaveauthed))
388 {
389 #ifdef SSL_ENABLE
390 if (must_starttls(ctl)) {
391 /* fail with mandatory STLS without repoll */
392 report(stderr, GT_("STLS is mandatory for this session, but server refused CAPA command.\n"));
393 report(stderr, GT_("CAPA command support is, however, necessary for STLS.\n"));
394 return ok;
395 } else if (maybe_starttls(ctl)) {
396 /* defeat opportunistic STLS */
397 xfree(ctl->sslproto);
398 ctl->sslproto = xstrdup("");
399 }
400 #endif
401 /* If strong authentication was opportunistic, retry without, else fail. */
402 switch (ctl->server.authenticate) {
403 case A_ANY:
404 ctl->server.authenticate = A_PASSWORD;
405 /* FALLTHROUGH */
406 case A_PASSWORD: /* this should only happen with TLS enabled */
407 return PS_REPOLL;
408 default:
409 return PS_AUTHFAIL;
410 }
411 }
412 }
413
414 #ifdef SSL_ENABLE
415 commonname = ctl->server.pollname;
416 if (ctl->server.via)
417 commonname = ctl->server.via;
418 if (ctl->sslcommonname)
419 commonname = ctl->sslcommonname;
420
421 if (maybe_starttls(ctl)) {
422 if (has_stls || must_starttls(ctl)) /* if TLS is mandatory, ignore capabilities */
423 {
424 /* Don't need to worry whether TLS is mandatory or
425 * opportunistic unless SSLOpen() fails (see below). */
426 if (gen_transact(sock, "STLS") == PS_SUCCESS
427 && (set_timeout(mytimeout), SSLOpen(sock, ctl->sslcert, ctl->sslkey, ctl->sslproto, ctl->sslcertck,
428 ctl->sslcertfile, ctl->sslcertpath, ctl->sslfingerprint, commonname,
429 ctl->server.pollname, &ctl->remotename)) != -1)
430 {
431 /*
432 * RFC 2595 says this:
433 *
434 * "Once TLS has been started, the client MUST discard cached
435 * information about server capabilities and SHOULD re-issue the
436 * CAPABILITY command. This is necessary to protect against
437 * man-in-the-middle attacks which alter the capabilities list prior
438 * to STARTTLS. The server MAY advertise different capabilities
439 * after STARTTLS."
440 *
441 * Now that we're confident in our TLS connection we can
442 * guarantee a secure capability re-probe.
443 */
444 set_timeout(0);
445 if (outlevel >= O_VERBOSE)
446 {
447 report(stdout, GT_("%s: upgrade to TLS succeeded.\n"), commonname);
448 }
449 clear_sessiondata();
450 ok = capa_probe(sock);
451 if (ok != PS_SUCCESS) {
452 return ok;
453 }
454 } else if (must_starttls(ctl)) {
455 /* Config required TLS but we couldn't guarantee it, so we must
456 * stop. */
457 set_timeout(0);
458 report(stderr, GT_("%s: upgrade to TLS failed.\n"), commonname);
459 return PS_SOCKET;
460 } else {
461 /* We don't know whether the connection is usable, and there's
462 * no command we can reasonably issue to test it (NOOP isn't
463 * allowed til post-authentication), so leave it in an unknown
464 * state, mark it as such, and check more carefully if things
465 * go wrong when we try to authenticate. */
466 set_timeout(0);
467 connection_may_have_tls_errors = TRUE;
468 if (outlevel >= O_VERBOSE)
469 {
470 report(stdout, GT_("%s: opportunistic upgrade to TLS failed, trying to continue.\n"), commonname);
471 }
472 }
473 }
474 } else { /* maybe_starttls() */
475 if (has_stls && outlevel >= O_VERBOSE) {
476 report(stdout, GT_("%s: WARNING: server offered STLS, but sslproto '' given.\n"), commonname);
477 }
478 } /* maybe_starttls() */
479 #endif /* SSL_ENABLE */
480
481 if (ctl->server.authenticate == A_SSH) {
482 return PS_SUCCESS;
483 }
484
485 #ifdef RPA_ENABLE
486 /* XXX FIXME: AUTH probing (RFC1734) should become global */
487 /* CompuServe POP3 Servers as of 990730 want AUTH first for RPA */
488 if (strstr(ctl->remotename, "@compuserve.com")
489 && ctl->server.authenticate == A_ANY)
490 {
491 /* AUTH command should return a list of available mechanisms. */
492 /* 2021 update: it is unclear which software still supports RPA these days.
493 This behavior (AUTH without a method argument, to query)
494 is not sanctioned by RFC-1734 but was/is apparently
495 supported by Compuserve and Microsoft for their NTLM:
496 https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-pop3/cb6829e1-d6f4-447b-9092-2671a257563c
497 */
498 if (gen_transact(sock, "AUTH") == 0)
499 {
500 char buffer[10];
501 flag has_rpa = FALSE;
502 int err;
503
504 while ((err = gen_recv(sock, buffer, sizeof(buffer))) == 0)
505 {
506 if (DOTLINE(buffer))
507 break;
508 if (strncasecmp(buffer, "rpa", 3) == 0)
509 has_rpa = TRUE;
510 }
511 if (err) {
512 return err;
513 }
514 if (has_rpa && !POP3_auth_rpa(ctl->remotename,
515 ctl->password, sock))
516 return PS_SUCCESS;
517 }
518
519 return PS_AUTHFAIL;
520 }
521 #endif /* RPA_ENABLE */
522
523 /*
524 * OK, we have an authentication type now.
525 */
526 #if defined(KERBEROS_V4)
527 /*
528 * Servers doing KPOP have to go through a dummy login sequence
529 * rather than doing SASL.
530 */
531 if (has_kerberos &&
532 ctl->server.service && (strcmp(ctl->server.service, KPOP_PORT)!=0)
533 && (ctl->server.authenticate == A_KERBEROS_V4
534 || ctl->server.authenticate == A_KERBEROS_V5
535 || ctl->server.authenticate == A_ANY))
536 {
537 ok = do_rfc1731(sock, "AUTH", ctl->server.truename);
538 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
539 break;
540 }
541 #endif /* defined(KERBEROS_V4) || defined(KERBEROS_V5) */
542
543 #if defined(GSSAPI)
544 if (has_gssapi &&
545 (ctl->server.authenticate == A_GSSAPI ||
546 (ctl->server.authenticate == A_ANY
547 && check_gss_creds("pop", ctl->server.truename) == PS_SUCCESS)))
548 {
549 ok = do_gssauth(sock,"AUTH","pop",ctl->server.truename,ctl->remotename);
550 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
551 break;
552 }
553 #endif /* defined(GSSAPI) */
554
555 #ifdef OPIE_ENABLE
556 if (has_otp &&
557 (ctl->server.authenticate == A_OTP ||
558 ctl->server.authenticate == A_ANY))
559 {
560 ok = do_otp(sock, "AUTH", ctl);
561 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
562 break;
563 }
564 #endif /* OPIE_ENABLE */
565
566 #ifdef NTLM_ENABLE
567 /* MSN servers require the use of NTLM (MSN) authentication */
568 if (!strcasecmp(ctl->server.pollname, "pop3.email.msn.com") ||
569 ctl->server.authenticate == A_MSN)
570 return (do_pop3_ntlm(sock, ctl, 1) == 0) ? PS_SUCCESS : PS_AUTHFAIL;
571 if (ctl->server.authenticate == A_NTLM || (has_ntlm && ctl->server.authenticate == A_ANY)) {
572 ok = do_pop3_ntlm(sock, ctl, 0);
573 if (ok == 0 || ctl->server.authenticate != A_ANY)
574 break;
575 }
576 #else
577 if (ctl->server.authenticate == A_NTLM || ctl->server.authenticate == A_MSN)
578 {
579 report(stderr,
580 GT_("Required NTLM capability not compiled into fetchmail\n"));
581 return PS_AUTHFAIL;
582 }
583 #endif
584
585 if (ctl->server.authenticate == A_CRAM_MD5 ||
586 (has_cram && ctl->server.authenticate == A_ANY))
587 {
588 ok = do_cram_md5(sock, "AUTH", ctl, NULL);
589 if (ok == PS_SUCCESS || ctl->server.authenticate != A_ANY)
590 break;
591 }
592
593 /* ordinary validation, no one-time password or RPA */
594 if ((ok = gen_transact(sock, "USER %s", ctl->remotename)))
595 break;
596
597 #ifdef OPIE_ENABLE
598 /* see RFC1938: A One-Time Password System */
599 if ((challenge = strstr(lastok, "otp-"))) {
600 char response[OPIE_RESPONSE_MAX+1];
601 int i;
602 char *n = xstrdup("");
603
604 i = opiegenerator(challenge, !strcmp(ctl->password, "opie") ? n : ctl->password, response);
605 free(n);
606 if ((i == -2) && !run.poll_interval) {
607 char secret[OPIE_SECRET_MAX+1];
608 fprintf(stderr, GT_("Secret pass phrase: "));
609 if (opiereadpass(secret, sizeof(secret), 0))
610 i = opiegenerator(challenge, secret, response);
611 memset(secret, 0, sizeof(secret));
612 };
613
614 if (i) {
615 ok = PS_ERROR;
616 break;
617 };
618
619 ok = gen_transact(sock, "PASS %s", response);
620 break;
621 }
622 #endif /* OPIE_ENABLE */
623
624 /* KPOP uses out-of-band authentication and does not check what
625 * we send here, so send some random fixed string, to avoid
626 * users switching *to* KPOP accidentally revealing their
627 * password */
628 if ((ctl->server.authenticate == A_ANY
629 || ctl->server.authenticate == A_KERBEROS_V4
630 || ctl->server.authenticate == A_KERBEROS_V5)
631 && (ctl->server.service != NULL
632 && strcmp(ctl->server.service, KPOP_PORT) == 0))
633 {
634 ok = gen_transact(sock, "PASS krb_ticket");
635 break;
636 }
637
638 /* check if we are actually allowed to send the password */
639 if (ctl->server.authenticate == A_ANY
640 || ctl->server.authenticate == A_PASSWORD) {
641 strlcpy(shroud, ctl->password, sizeof(shroud));
642 ok = gen_transact(sock, "PASS %s", ctl->password);
643 } else {
644 report(stderr, GT_("We've run out of allowed authenticators and cannot continue.\n"));
645 ok = PS_AUTHFAIL;
646 }
647 memset(shroud, 0x55, sizeof(shroud));
648 shroud[0] = '\0';
649 break;
650
651 case P_APOP:
652 /* build MD5 digest from greeting timestamp + password */
653 /* find start of timestamp */
654 for (start = greeting; *start != 0 && *start != '<'; start++)
655 continue;
656 if (*start == 0) {
657 report(stderr,
658 GT_("Required APOP timestamp not found in greeting\n"));
659 return(PS_AUTHFAIL);
660 }
661
662 /* find end of timestamp */
663 for (end = start; *end != 0 && *end != '>'; end++)
664 continue;
665 if (*end == 0 || end == start + 1) {
666 report(stderr,
667 GT_("Timestamp syntax error in greeting\n"));
668 return(PS_AUTHFAIL);
669 }
670 else
671 *++end = '\0';
672
673 /* SECURITY: 2007-03-17
674 * Strictly validating the presented challenge for RFC-822
675 * conformity (it must be a msg-id in terms of that standard) is
676 * supposed to make attacks against the MD5 implementation
677 * harder[1]
678 *
679 * [1] "Security vulnerability in APOP authentication",
680 * Gaëtan Leurent, fetchmail-devel, 2007-03-17 */
681 if (!rfc822_valid_msgid((unsigned char *)start)) {
682 report(stderr,
683 GT_("Invalid APOP timestamp.\n"));
684 return PS_AUTHFAIL;
685 }
686
687 /* copy timestamp and password into digestion buffer */
688 msg = (char *)xmalloc((end-start+1) + strlen(ctl->password) + 1);
689 strcpy(msg,start);
690 strcat(msg,ctl->password);
691 strcpy((char *)ctl->digest, MD5Digest((unsigned char *)msg));
692 free(msg);
693
694 ok = gen_transact(sock, "APOP %s %s", ctl->remotename, (char *)ctl->digest);
695 break;
696
697 case P_RPOP:
698 if ((ok = gen_transact(sock,"USER %s", ctl->remotename)) == 0) {
699 strlcpy(shroud, ctl->password, sizeof(shroud));
700 ok = gen_transact(sock, "RPOP %s", ctl->password);
701 memset(shroud, 0x55, sizeof(shroud));
702 shroud[0] = '\0';
703 }
704 break;
705
706 default:
707 report(stderr, GT_("Undefined protocol request in POP3_auth\n"));
708 ok = PS_ERROR;
709 }
710
711 #ifdef SSL_ENABLE
712 /* this is for servers which claim to support TLS, but actually
713 * don't! */
714 if (connection_may_have_tls_errors
715 && (ok == PS_SOCKET || ok == PS_PROTOCOL))
716 {
717 xfree(ctl->sslproto);
718 ctl->sslproto = xstrdup("");
719 /* repoll immediately without TLS */
720 ok = PS_REPOLL;
721 }
722 #endif
723
724 if (ok != 0)
725 {
726 /* maybe we detected a lock-busy condition? */
727 if (ok == PS_LOCKBUSY)
728 report(stderr, GT_("lock busy! Is another session active?\n"));
729
730 return(ok);
731 }
732
733 /* we're approved */
734 return(PS_SUCCESS);
735 }
736
737 /* cut off C string at first POSIX space */
trim(char * s)738 static void trim(char *s) {
739 s += strcspn(s, POSIX_space);
740 s[0] = '\0';
741 }
742
743 /* XXX FIXME: using the Message-ID is unsafe, some messages (spam,
744 * broken messages) do not have Message-ID headers, and messages without
745 * those appear to break this code and cause fetchmail (at least version
746 * 6.2.3) to not delete such messages properly after retrieval.
747 * See Sourceforge Bug #780933.
748 *
749 * The other problem is that the TOP command itself is optional, too... */
pop3_gettopid(int sock,int num,char * id,size_t idsize)750 static int pop3_gettopid(int sock, int num , char *id, size_t idsize)
751 {
752 int ok;
753 int got_it;
754 char buf [POPBUFSIZE+1];
755 snprintf(buf, sizeof(buf), "TOP %d 1", num);
756 if ((ok = gen_transact(sock, "%s", buf)) != 0)
757 return ok;
758 got_it = 0;
759 while (gen_recv(sock, buf, sizeof(buf)) == 0)
760 {
761 if (DOTLINE(buf))
762 break;
763 if (!got_it && 0 == strncasecmp("Message-Id:", buf, 11)) {
764 char *p = buf + 11;
765 got_it = 1;
766 p += strspn(p, POSIX_space);
767 strlcpy(id, p, idsize);
768 trim(id);
769 }
770 }
771 /* XXX FIXME: do not return success here if no Message-ID header was
772 * found. */
773 return 0;
774 }
775
776 /** Parse the UID response (leading +OK must have been
777 * stripped off) in buf, store the number in gotnum, and store the ID
778 * into the caller-provided buffer "id" of size "idsize".
779 * Returns PS_SUCCESS or PS_PROTOCOL for failure. */
parseuid(const char * buf,unsigned long * gotnum,char * id,size_t idsize)780 static int parseuid(const char *buf, unsigned long *gotnum, char *id, size_t idsize)
781 {
782 const char *i;
783 char *j;
784
785 /* skip leading blanks ourselves */
786 i = buf;
787 i += strspn(i, POSIX_space);
788 errno = 0;
789 *gotnum = strtoul(i, &j, 10);
790 if (j == i || !*j || errno || NULL == strchr(POSIX_space, *j)) {
791 report(stderr, GT_("Cannot handle UIDL response from upstream server.\n"));
792 return PS_PROTOCOL;
793 }
794 j += strspn(j, POSIX_space);
795 strlcpy(id, j, idsize);
796 trim(id);
797 return PS_SUCCESS;
798 }
799
800 /** request UIDL for single message \a num and stuff the result into the
801 * buffer \a id which can hold \a idsize bytes */
pop3_getuidl(int sock,int num,char * id,size_t idsize)802 static int pop3_getuidl(int sock, int num, char *id /** output */, size_t idsize)
803 {
804 int ok;
805 char buf [POPBUFSIZE+1];
806 unsigned long gotnum;
807
808 gen_send(sock, "UIDL %d", num);
809 if ((ok = pop3_ok(sock, buf)) != 0)
810 return(ok);
811 if ((ok = parseuid(buf, &gotnum, id, idsize)))
812 return ok;
813 if (gotnum != (unsigned long)num) {
814 report(stderr, GT_("Server responded with UID for wrong message.\n"));
815 return PS_PROTOCOL;
816 }
817 return(PS_SUCCESS);
818 }
819
820 /** Do a binary search with single UIDL commands to find the first
821 * unseen message. */
pop3_fastuidl(int sock,struct query * ctl,unsigned int count,int * newp)822 static int pop3_fastuidl( int sock, struct query *ctl, unsigned int count, int *newp)
823 {
824 int ok;
825 unsigned int first_nr, last_nr, try_nr;
826 char id [IDLEN+1];
827
828 first_nr = 0;
829 last_nr = count + 1;
830 while (first_nr < last_nr - 1)
831 {
832 struct uid_db_record *rec;
833
834 try_nr = (first_nr + last_nr) / 2;
835 if ((ok = pop3_getuidl(sock, try_nr, id, sizeof(id))) != 0)
836 return ok;
837 if ((rec = find_uid_by_id(&ctl->oldsaved, id)))
838 {
839 flag mark = rec->status;
840 if (mark == UID_DELETED || mark == UID_EXPUNGED)
841 {
842 if (outlevel >= O_VERBOSE)
843 report(stderr, GT_("id=%s (num=%u) was deleted, but is still present!\n"), id, try_nr);
844 /* just mark it as seen now! */
845 rec->status = mark = UID_SEEN;
846 }
847
848 /* narrow the search region! */
849 if (mark == UID_UNSEEN)
850 {
851 if (outlevel >= O_DEBUG)
852 report(stdout, GT_("%u is unseen\n"), try_nr);
853 last_nr = try_nr;
854 }
855 else
856 first_nr = try_nr;
857
858 /* save the number */
859 set_uid_db_num(&ctl->oldsaved, rec, try_nr);
860 }
861 else
862 {
863 if (outlevel >= O_DEBUG)
864 report(stdout, GT_("%u is unseen\n"), try_nr);
865 last_nr = try_nr;
866
867 /* save it */
868 rec = uid_db_insert(&ctl->oldsaved, id, UID_UNSEEN);
869 set_uid_db_num(&ctl->oldsaved, rec, try_nr);
870 }
871 }
872 if (outlevel >= O_DEBUG && last_nr <= count)
873 report(stdout, GT_("%u is first unseen\n"), last_nr);
874
875 /* update last! */
876 *newp = count - first_nr;
877 last = first_nr;
878 return 0;
879 }
880
pop3_slowuidl(int sock,struct query * ctl,int * countp,int * newp)881 static int pop3_slowuidl( int sock, struct query *ctl, int *countp, int *newp)
882 {
883 /* XXX FIXME: this code is severely broken. A Cc:d mailing list
884 * message will arrive twice with the same Message-ID, so this
885 * slowuidl code will break. Same goes for messages without
886 * Message-ID headers at all. This code would best be removed. */
887 /* This approach tries to get the message headers from the
888 * remote hosts and compares the message-id to the already known
889 * ones:
890 * + if the first message containes a new id, all messages on
891 * the server will be new
892 * + if the first is known, try to estimate the last known message
893 * on the server and check. If this works you know the total number
894 * of messages to get.
895 * + Otherwise run a binary search to determine the last known message
896 */
897 struct uid_db_record *rec;
898 int ok, nolinear = 0;
899 int first_nr, n_recs, try_id, try_nr, add_id;
900 int num;
901 char id [IDLEN+1];
902
903 if ((ok = pop3_gettopid(sock, 1, id, sizeof(id))) != 0)
904 return ok;
905
906 rec = first_uid_in_db(&ctl->oldsaved, id);
907 if (!rec) {
908 /* the first message is unknown -> all messages are new */
909 *newp = *countp;
910 return 0;
911 }
912 first_nr = rec->pos;
913
914 /* check where we expect the latest known message */
915 n_recs = uid_db_n_records(&ctl->oldsaved);
916 try_id = n_recs - first_nr; /* -1 + 1 */
917 if( try_id > 1 ) {
918 if( try_id <= *countp ) {
919 if ((ok = pop3_gettopid(sock, try_id, id, sizeof(id))) != 0)
920 return ok;
921
922 rec = last_uid_in_db(&ctl->oldsaved, id);
923 try_nr = rec ? (int)rec->pos : -1;
924 } else {
925 try_id = *countp+1;
926 try_nr = -1;
927 }
928 if( try_nr != n_recs -1 ) {
929 /* some messages inbetween have been deleted... */
930 if( try_nr == -1 ) {
931 nolinear = 1;
932
933 for( add_id = 1<<30; add_id > try_id-1; add_id >>= 1 )
934 ;
935 for( ; add_id; add_id >>= 1 ) {
936 if( try_nr == -1 ) {
937 if( try_id - add_id <= 1 ) {
938 continue;
939 }
940 try_id -= add_id;
941 } else
942 try_id += add_id;
943
944 if ((ok = pop3_gettopid(sock, try_id, id, sizeof(id))) != 0)
945 return ok;
946
947 rec = find_uid_by_id(&ctl->oldsaved, id);
948 try_nr = rec ? (int)rec->pos : -1;
949 }
950 if( try_nr == -1 ) {
951 try_id--;
952 }
953 } else {
954 report(stderr,
955 GT_("Messages inserted into list on server. Cannot handle this.\n"));
956 return -1;
957 }
958 }
959 }
960 /* the first try_id messages are known -> copy them to the newsaved list */
961 for( num = first_nr; num < n_recs; num++ )
962 {
963 rec = find_uid_by_pos(&ctl->oldsaved, num);
964
965 rec = uid_db_insert(&ctl->newsaved, rec->id, rec->status);
966 set_uid_db_num(&ctl->newsaved, rec, num - first_nr + 1);
967 }
968
969 if( nolinear ) {
970 clear_uid_db(&ctl->oldsaved);
971 last = try_id;
972 }
973
974 *newp = *countp - try_id;
975 return 0;
976 }
977
pop3_getrange(int sock,struct query * ctl,const char * folder,int * countp,int * newp,int * bytes)978 static int pop3_getrange(int sock,
979 struct query *ctl,
980 const char *folder,
981 int *countp, int *newp, int *bytes)
982 /* get range of messages to be fetched */
983 {
984 int ok;
985 char buf [POPBUFSIZE+1];
986
987 (void)folder;
988 /* Ensure that the new list is properly empty */
989 clear_uid_db(&ctl->newsaved);
990
991 #ifdef MBOX
992 /* Alain Knaff suggests this, but it's not RFC standard */
993 if (folder)
994 if ((ok = gen_transact(sock, "MBOX %s", folder)))
995 return ok;
996 #endif /* MBOX */
997
998 /* get the total message count */
999 gen_send(sock, "STAT");
1000 ok = pop3_ok(sock, buf);
1001 if (ok == 0) {
1002 int asgn;
1003
1004 asgn = sscanf(buf,"%d %d", countp, bytes);
1005 if (asgn != 2)
1006 return PS_PROTOCOL;
1007 } else
1008 return(ok);
1009
1010 /*
1011 * Newer, RFC-1725/1939-conformant POP servers may not have the LAST
1012 * command. We work as hard as possible to hide this, but it makes
1013 * counting new messages intrinsically quadratic in the worst case.
1014 */
1015 last = 0;
1016 *newp = -1;
1017 /* if there are messages, and UIDL is desired, use UIDL
1018 * also use UIDL if fetchall is unset */
1019 if (*countp > 0 && (!ctl->fetchall || ctl->server.uidl))
1020 {
1021 int fastuidl;
1022 char id [IDLEN+1];
1023
1024 set_uid_db_num_pos_0(&ctl->oldsaved, *countp);
1025 set_uid_db_num_pos_0(&ctl->newsaved, *countp);
1026
1027 /* should we do fast uidl this time? */
1028 fastuidl = ctl->fastuidl;
1029 if (*countp > 7 && /* linear search is better if there are few mails! */
1030 !ctl->fetchall && /* with fetchall, all uids are required */
1031 !ctl->flush && /* with flush, it is safer to disable fastuidl */
1032 NUM_NONZERO (fastuidl))
1033 {
1034 if (fastuidl == 1)
1035 dofastuidl = 1;
1036 else
1037 dofastuidl = ctl->fastuidlcount != 0;
1038 }
1039 else
1040 dofastuidl = 0;
1041
1042 if (!ctl->server.uidl) {
1043 gen_send(sock, "LAST");
1044 ok = pop3_ok(sock, buf);
1045 } else
1046 ok = 1;
1047
1048 if (ok == 0)
1049 {
1050 /* scan LAST reply */
1051 if (sscanf(buf, "%d", &last) == 0)
1052 {
1053 report(stderr, GT_("protocol error\n"));
1054 return(PS_ERROR);
1055 }
1056 *newp = (*countp - last);
1057 }
1058 else
1059 {
1060 /* do UIDL */
1061 if (dofastuidl)
1062 return(pop3_fastuidl( sock, ctl, *countp, newp));
1063 /* grab the mailbox's UID list */
1064 if (gen_transact(sock, "UIDL") != 0)
1065 {
1066 /* don't worry, yet! do it the slow way */
1067 if (pop3_slowuidl(sock, ctl, countp, newp))
1068 {
1069 report(stderr, GT_("protocol error while fetching UIDLs\n"));
1070 return(PS_ERROR);
1071 }
1072 }
1073 else
1074 {
1075 /* UIDL worked - parse reply */
1076 unsigned long unum;
1077
1078 *newp = 0;
1079 while (gen_recv(sock, buf, sizeof(buf)) == PS_SUCCESS)
1080 {
1081 if (DOTLINE(buf))
1082 break;
1083
1084 if (parseuid(buf, &unum, id, sizeof(id)) == PS_SUCCESS)
1085 {
1086 struct uid_db_record *old_rec, *new_rec;
1087
1088 new_rec = uid_db_insert(&ctl->newsaved, id, UID_UNSEEN);
1089
1090 if ((old_rec = find_uid_by_id(&ctl->oldsaved, id)))
1091 {
1092 flag mark = old_rec->status;
1093 if (mark == UID_DELETED || mark == UID_EXPUNGED)
1094 {
1095 /* XXX FIXME: switch 3 occurrences from
1096 * (int)unum or (unsigned int)unum to
1097 * remove the cast and use %lu - not now
1098 * though, time for new release */
1099 if (outlevel >= O_VERBOSE)
1100 report(stderr, GT_("id=%s (num=%d) was deleted, but is still present!\n"), id, (int)unum);
1101 /* just mark it as seen now! */
1102 old_rec->status = mark = UID_SEEN;
1103 }
1104 new_rec->status = mark;
1105 if (mark == UID_UNSEEN)
1106 {
1107 (*newp)++;
1108 if (outlevel >= O_DEBUG)
1109 report(stdout, GT_("%u is unseen\n"), (unsigned int)unum);
1110 }
1111 }
1112 else
1113 {
1114 (*newp)++;
1115 if (outlevel >= O_DEBUG)
1116 report(stdout, GT_("%u is unseen\n"), (unsigned int)unum);
1117 /* add it to oldsaved also! In case, we do not
1118 * swap the lists (say, due to socket error),
1119 * the same mail will not be downloaded again.
1120 */
1121 old_rec = uid_db_insert(&ctl->oldsaved, id, UID_UNSEEN);
1122
1123 }
1124 /*
1125 * save the number if it will be needed later on
1126 * (messsage will either be fetched or deleted)
1127 */
1128 if (new_rec->status == UID_UNSEEN || ctl->flush) {
1129 set_uid_db_num(&ctl->oldsaved, old_rec, unum);
1130 set_uid_db_num(&ctl->newsaved, new_rec, unum);
1131 }
1132 } else
1133 return PS_ERROR;
1134 } /* multi-line loop for UIDL reply */
1135 } /* UIDL parser */
1136 } /* do UIDL */
1137 }
1138
1139 return(PS_SUCCESS);
1140 }
1141
pop3_getpartialsizes(int sock,int first,int last,int * sizes)1142 static int pop3_getpartialsizes(int sock, int first, int last, int *sizes)
1143 /* capture the size of message #first */
1144 {
1145 int ok = 0, i, num;
1146 char buf [POPBUFSIZE+1];
1147 unsigned int size;
1148
1149 for (i = first; i <= last; i++) {
1150 gen_send(sock, "LIST %d", i);
1151 if ((ok = pop3_ok(sock, buf)) != 0)
1152 return(ok);
1153 if (sscanf(buf, "%d %u", &num, &size) == 2) {
1154 if (num == i)
1155 sizes[i - first] = size;
1156 else
1157 /* warn about possible attempt to induce buffer overrun
1158 *
1159 * we expect server reply message number and requested
1160 * message number to match */
1161 report(stderr, "Warning: ignoring bogus data for message sizes returned by server.\n");
1162 }
1163 }
1164 return(ok);
1165 }
1166
pop3_getsizes(int sock,int count,int * sizes)1167 static int pop3_getsizes(int sock, int count, int *sizes)
1168 /* capture the sizes of all messages */
1169 {
1170 int ok;
1171
1172 if ((ok = gen_transact(sock, "LIST")) != 0)
1173 return(ok);
1174 else
1175 {
1176 char buf [POPBUFSIZE+1];
1177
1178 while ((ok = gen_recv(sock, buf, sizeof(buf))) == 0)
1179 {
1180 unsigned int num, size;
1181
1182 if (DOTLINE(buf))
1183 break;
1184 else if (sscanf(buf, "%u %u", &num, &size) == 2) {
1185 if (num > 0 && num <= (unsigned)count)
1186 sizes[num - 1] = size;
1187 else
1188 /* warn about possible attempt to induce buffer overrun */
1189 report(stderr, "Warning: ignoring bogus data for message sizes returned by server.\n");
1190 }
1191 }
1192
1193 return(ok);
1194 }
1195 }
1196
pop3_is_old(int sock,struct query * ctl,int num)1197 static int pop3_is_old(int sock, struct query *ctl, int num)
1198 /* is the given message old? */
1199 {
1200 struct uid_db_record *rec;
1201
1202 if (!uid_db_n_records(&ctl->oldsaved))
1203 return (num <= last);
1204 else if (dofastuidl)
1205 {
1206 char id [IDLEN+1];
1207
1208 if (num <= last)
1209 return(TRUE);
1210
1211 /* in fast uidl, we manipulate the old list only! */
1212
1213 if ((rec = find_uid_by_num(&ctl->oldsaved, num)))
1214 {
1215 /* we already have the id! */
1216 return(rec->status != UID_UNSEEN);
1217 }
1218
1219 /* get the uidl first! */
1220 if (pop3_getuidl(sock, num, id, sizeof(id)) != PS_SUCCESS)
1221 return(TRUE);
1222
1223 if ((rec = find_uid_by_id(&ctl->oldsaved, id))) {
1224 /* we already have the id! */
1225 set_uid_db_num(&ctl->oldsaved, rec, num);
1226 return(rec->status != UID_UNSEEN);
1227 }
1228
1229 /* save it */
1230 rec = uid_db_insert(&ctl->oldsaved, id, UID_UNSEEN);
1231 set_uid_db_num(&ctl->oldsaved, rec, num);
1232
1233 return(FALSE);
1234 } else {
1235 rec = find_uid_by_num(&ctl->newsaved, num);
1236 return !rec || rec->status != UID_UNSEEN;
1237 }
1238 }
1239
pop3_fetch(int sock,struct query * ctl,int number,int * lenp)1240 static int pop3_fetch(int sock, struct query *ctl, int number, int *lenp)
1241 /* request nth message */
1242 {
1243 int ok;
1244 char buf[POPBUFSIZE+1];
1245
1246 #ifdef SDPS_ENABLE
1247 /*
1248 * See http://www.demon.net/helpdesk/producthelp/mail/sdps-tech.html/
1249 * for a description of what we're parsing here.
1250 * -- updated 2006-02-22
1251 */
1252 if (ctl->server.sdps)
1253 {
1254 int linecount = 0;
1255
1256 sdps_envfrom = (char *)NULL;
1257 sdps_envto = (char *)NULL;
1258 gen_send(sock, "*ENV %d", number);
1259 do {
1260 if (gen_recv(sock, buf, sizeof(buf)))
1261 {
1262 break;
1263 }
1264 linecount++;
1265 switch (linecount) {
1266 case 4:
1267 /* No need to wrap envelope from address */
1268 /* FIXME: some parts of fetchmail don't handle null
1269 * envelope senders, so use <> to mark null sender
1270 * as a workaround. */
1271 if (strspn(buf, " \t") == strlen(buf))
1272 strcpy(buf, "<>");
1273 sdps_envfrom = (char *)xmalloc(strlen(buf)+1);
1274 strcpy(sdps_envfrom,buf);
1275 break;
1276 case 5:
1277 /* Wrap address with To: <> so nxtaddr() likes it */
1278 sdps_envto = (char *)xmalloc(strlen(buf)+7);
1279 sprintf(sdps_envto,"To: <%s>",buf);
1280 break;
1281 }
1282 } while
1283 (!(buf[0] == '.' && (buf[1] == '\r' || buf[1] == '\n' || buf[1] == '\0')));
1284 }
1285 #else
1286 (void)ctl;
1287 #endif /* SDPS_ENABLE */
1288
1289 /*
1290 * Though the POP RFCs don't document this fact, on almost every
1291 * POP3 server I know of messages are marked "seen" only at the
1292 * time the OK response to a RETR is issued.
1293 *
1294 * This means we can use TOP to fetch the message without setting its
1295 * seen flag. This is good! It means that if the protocol exchange
1296 * craps out during the message, it will still be marked `unseen' on
1297 * the server. (Exception: in early 1999 SpryNet's POP3 servers were
1298 * reported to mark messages seen on a TOP fetch.)
1299 *
1300 * However...*don't* do this if we're using keep to suppress deletion!
1301 * In that case, marking the seen flag is the only way to prevent the
1302 * message from being re-fetched on subsequent runs.
1303 *
1304 * Also use RETR (that means no TOP, no peek) if fetchall is on.
1305 * This gives us a workaround for servers like usa.net's that bungle
1306 * TOP. It's pretty harmless because fetchall guarantees that any
1307 * message dropped by an interrupted RETR will be picked up on the
1308 * next poll of the site.
1309 *
1310 * We take advantage here of the fact that, according to all the
1311 * POP RFCs, "if the number of lines requested by the POP3 client
1312 * is greater than than the number of lines in the body, then the
1313 * POP3 server sends the entire message.").
1314 *
1315 * The line count passed (99999999) is the maximum value CompuServe will
1316 * accept; it's much lower than the natural value 2147483646 (the maximum
1317 * twos-complement signed 32-bit integer minus 1) */
1318 if (!peek_capable)
1319 gen_send(sock, "RETR %d", number);
1320 else
1321 gen_send(sock, "TOP %d 99999999", number);
1322 if ((ok = pop3_ok(sock, buf)) != 0)
1323 return(ok);
1324
1325 *lenp = -1; /* we got sizes from the LIST response */
1326
1327 return(PS_SUCCESS);
1328 }
1329
mark_uid_seen(struct query * ctl,int number)1330 static void mark_uid_seen(struct query *ctl, int number)
1331 /* Tell the UID code we've seen this. */
1332 {
1333 struct uid_db_record *rec;
1334
1335 if ((rec = find_uid_by_num(&ctl->newsaved, number)))
1336 rec->status = UID_SEEN;
1337 /* mark it as seen in oldsaved also! In case, we do not swap the lists
1338 * (say, due to socket error), the same mail will not be downloaded
1339 * again.
1340 */
1341 if ((rec = find_uid_by_num(&ctl->oldsaved, number)))
1342 rec->status = UID_SEEN;
1343 }
1344
pop3_delete(int sock,struct query * ctl,int number)1345 static int pop3_delete(int sock, struct query *ctl, int number)
1346 /* delete a given message */
1347 {
1348 struct uid_db_record *rec;
1349 int ok;
1350 mark_uid_seen(ctl, number);
1351 /* actually, mark for deletion -- doesn't happen until QUIT time */
1352 ok = gen_transact(sock, "DELE %d", number);
1353 if (ok != PS_SUCCESS)
1354 return(ok);
1355
1356 if ((rec = find_uid_by_num(dofastuidl ? &ctl->oldsaved : &ctl->newsaved, number)))
1357 rec->status = UID_DELETED;
1358
1359 return(PS_SUCCESS);
1360 }
1361
pop3_mark_seen(int sock,struct query * ctl,int number)1362 static int pop3_mark_seen(int sock, struct query *ctl, int number)
1363 /* mark a given message as seen */
1364 {
1365 (void)sock;
1366 mark_uid_seen(ctl, number);
1367 return(PS_SUCCESS);
1368 }
1369
pop3_logout(int sock,struct query * ctl)1370 static int pop3_logout(int sock, struct query *ctl)
1371 /* send logout command */
1372 {
1373 int ok;
1374
1375 ok = gen_transact(sock, "QUIT");
1376 if (!ok)
1377 expunge_uids(ctl);
1378
1379 return(ok);
1380 }
1381
1382 static const struct method pop3 =
1383 {
1384 "POP3", /* Post Office Protocol v3 */
1385 "pop3", /* port for plain and TLS POP3 */
1386 "pop3s", /* port for SSL POP3 */
1387 FALSE, /* this is not a tagged protocol */
1388 TRUE, /* this uses a message delimiter */
1389 pop3_ok, /* parse command response */
1390 pop3_getauth, /* get authorization */
1391 pop3_getrange, /* query range of messages */
1392 pop3_getsizes, /* we can get a list of sizes */
1393 pop3_getpartialsizes, /* we can get the size of 1 mail */
1394 pop3_is_old, /* how do we tell a message is old? */
1395 pop3_fetch, /* request given message */
1396 NULL, /* no way to fetch body alone */
1397 NULL, /* no message trailer */
1398 pop3_delete, /* how to delete a message */
1399 pop3_mark_seen, /* how to mark a message as seen */
1400 NULL, /* no action at end of mailbox */
1401 pop3_logout, /* log out, we're done */
1402 FALSE, /* no, we can't re-poll */
1403 pop3_setup, /* setup method */
1404 pop3_cleanup /* cleanup method */
1405 };
1406
doPOP3(struct query * ctl)1407 int doPOP3 (struct query *ctl)
1408 /* retrieve messages using POP3 */
1409 {
1410 #ifndef MBOX
1411 if (ctl->mailboxes->id) {
1412 fprintf(stderr,GT_("Option --folder is not supported with POP3\n"));
1413 return(PS_SYNTAX);
1414 }
1415 #endif /* MBOX */
1416
1417 return(do_protocol(ctl, &pop3));
1418 }
1419 #endif /* POP3_ENABLE */
1420
1421 /* pop3.c ends here */
1422