2 // NNTP server module FIXME THIS IS NOT FINISHED
4 // Copyright (c) 2014 by the citadel.org team
6 // This program is open source software; you can redistribute it and/or modify
7 // it under the terms of the GNU General Public License version 3.
9 // This program is distributed in the hope that it will be useful,
10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 // GNU General Public License for more details.
24 #include <sys/types.h>
27 #if TIME_WITH_SYS_TIME
28 # include <sys/time.h>
32 # include <sys/time.h>
42 #include <sys/socket.h>
43 #include <netinet/in.h>
44 #include <arpa/inet.h>
45 #include <libcitadel.h>
48 #include "citserver.h"
56 #include "internet_addressing.h"
59 #include "clientsocket.h"
60 #include "locate_host.h"
61 #include "citadel_dirs.h"
62 #include "ctdl_module.h"
63 #include "serv_nntp.h"
67 // ***************** BEGIN UTILITY FUNCTIONS THAT COULD BE MOVED ELSEWHERE LATER **************
71 // Tests whether the supplied string is a valid newsgroup name
72 // Returns true (nonzero) or false (0)
74 int is_valid_newsgroup_name(char *name) {
79 if (!strncasecmp(name, "ctdl.", 5)) return(0);
83 if (isalpha(ptr[0])) {
87 if ( (isalnum(ptr[0]))
103 // Convert a Citadel room name to a valid newsgroup name
105 void room_to_newsgroup(char *target, char *source, size_t target_size) {
110 if (is_valid_newsgroup_name(source)) {
111 strncpy(target, source, target_size);
115 strcpy(target, "ctdl.");
120 while (ch=*ptr++, ch!=0) {
121 if (len >= target_size) return;
130 target[len++] = '+' ;
131 sprintf(&target[len], "%02x", ch);
140 // Convert a newsgroup name to a Citadel room name.
141 // This function recognizes names converted with room_to_newsgroup() and restores them with full fidelity.
143 void newsgroup_to_room(char *target, char *source, size_t target_size) {
148 if (strncasecmp(source, "ctdl.", 5)) { // not a converted room name; pass through as-is
149 strncpy(target, source, target_size);
155 char *ptr = &source[5];
158 while (ch=*ptr++, ch!=0) {
159 if (len >= target_size) return;
166 digit = strtol(hex, NULL, 16);
175 // ***************** END UTILITY FUNCTIONS THAT COULD BE MOVED ELSEWHERE LATER **************
180 // Here's where our NNTP session begins its happy day.
182 void nntp_greeting(void)
184 strcpy(CC->cs_clientname, "NNTP session");
185 CC->cs_flags |= CS_STEALTH;
187 CC->session_specific_data = malloc(sizeof(citnntp));
188 citnntp *nntpstate = (citnntp *) CC->session_specific_data;
189 memset(nntpstate, 0, sizeof(citnntp));
191 if (CC->nologin==1) {
192 cprintf("451 Too many connections are already open; please try again later.\r\n");
193 CC->kill_me = KILLME_MAX_SESSIONS_EXCEEDED;
197 // Display the standard greeting
198 cprintf("200 %s NNTP Citadel server is not finished yet\r\n", config.c_fqdn);
203 // NNTPS is just like NNTP, except it goes crypto right away.
205 void nntps_greeting(void) {
206 CtdlModuleStartCryptoMsgs(NULL, NULL, NULL);
208 if (!CC->redirect_ssl) CC->kill_me = KILLME_NO_CRYPTO; /* kill session if no crypto */
215 // implements the STARTTLS command
217 void nntp_starttls(void)
219 char ok_response[SIZ];
220 char nosup_response[SIZ];
221 char error_response[SIZ];
223 sprintf(ok_response, "382 Begin TLS negotiation now\r\n");
224 sprintf(nosup_response, "502 Can not initiate TLS negotiation\r\n");
225 sprintf(error_response, "580 Internal error\r\n");
226 CtdlModuleStartCryptoMsgs(ok_response, nosup_response, error_response);
231 // Implements the CAPABILITY command
233 void nntp_capabilities(void)
235 cprintf("101 Capability list:\r\n");
236 cprintf("IMPLEMENTATION Citadel v%d.%02d\r\n", (REV_LEVEL/100), (REV_LEVEL%100));
237 cprintf("VERSION 2\r\n");
238 cprintf("READER\r\n");
239 cprintf("MODE-READER\r\n");
240 cprintf("LIST ACTIVE NEWSGROUPS\r\n");
242 cprintf("STARTTLS\r\n");
244 if (!CC->logged_in) {
245 cprintf("AUTHINFO USER\r\n");
252 // Implements the QUIT command
256 cprintf("221 Goodbye...\r\n");
257 CC->kill_me = KILLME_CLIENT_LOGGED_OUT;
262 // Cleanup hook for this module
264 void nntp_cleanup(void)
266 /* nothing here yet */
271 // Implements the AUTHINFO USER command (RFC 4643)
273 void nntp_authinfo_user(const char *username)
275 int a = CtdlLoginExistingUser(NULL, username);
277 case login_already_logged_in:
278 cprintf("482 Already logged in\r\n");
280 case login_too_many_users:
281 cprintf("481 Too many users are already online (maximum is %d)\r\n", config.c_maxsessions);
284 cprintf("381 Password required for %s\r\n", CC->curr_user);
286 case login_not_found:
287 cprintf("481 %s not found\r\n", username);
290 cprintf("502 Internal error\r\n");
296 // Implements the AUTHINFO PASS command (RFC 4643)
298 void nntp_authinfo_pass(const char *buf)
302 a = CtdlTryPassword(buf, strlen(buf));
305 case pass_already_logged_in:
306 cprintf("482 Already logged in\r\n");
309 cprintf("482 Authentication commands issued out of sequence\r\n");
311 case pass_wrong_password:
312 cprintf("481 Authentication failed\r\n");
315 cprintf("281 Authentication accepted\r\n");
322 // Implements the AUTHINFO extension (RFC 4643) in USER/PASS mode
324 void nntp_authinfo(const char *cmd) {
326 if (!strncasecmp(cmd, "authinfo user ", 14)) {
327 nntp_authinfo_user(&cmd[14]);
330 else if (!strncasecmp(cmd, "authinfo pass ", 14)) {
331 nntp_authinfo_pass(&cmd[14]);
335 cprintf("502 command unavailable\r\n");
341 // Utility function to fetch the current list of message numbers in a room
343 struct nntp_msglist nntp_fetch_msglist(struct ctdlroom *qrbuf) {
344 struct nntp_msglist nm;
345 struct cdbdata *cdbfr;
347 cdbfr = cdb_fetch(CDB_MSGLISTS, &qrbuf->QRnumber, sizeof(long));
349 nm.msgnums = (long*)cdbfr->ptr;
351 nm.num_msgs = cdbfr->len / sizeof(long);
363 // Output a room name (newsgroup name) in formats required for LIST and NEWGROUPS command
365 void output_roomname_in_list_format(struct ctdlroom *qrbuf, int which_format, char *wildmat_pattern) {
367 struct nntp_msglist nm;
368 long low_water_mark = 0;
369 long high_water_mark = 0;
371 room_to_newsgroup(n_name, qrbuf->QRname, sizeof n_name);
373 if ((wildmat_pattern != NULL) && (!IsEmptyStr(wildmat_pattern))) {
374 if (!wildmat(n_name, wildmat_pattern)) {
379 nm = nntp_fetch_msglist(qrbuf);
380 if ((nm.num_msgs > 0) && (nm.msgnums != NULL)) {
381 low_water_mark = nm.msgnums[0];
382 high_water_mark = nm.msgnums[nm.num_msgs - 1];
385 // Only the mandatory formats are supported
386 switch(which_format) {
387 case NNTP_LIST_ACTIVE:
388 // FIXME we have hardcoded "n" for "no posting allowed" -- fix when we add posting
389 cprintf("%s %ld %ld n\r\n", n_name, high_water_mark, low_water_mark);
391 case NNTP_LIST_NEWSGROUPS:
392 cprintf("%s %s\r\n", n_name, qrbuf->QRname);
396 if (nm.msgnums != NULL) {
403 // Called once per room by nntp_newgroups() to qualify and possibly output a single room
405 void nntp_newgroups_backend(struct ctdlroom *qrbuf, void *data)
409 time_t thetime = *(time_t *)data;
411 CtdlRoomAccess(qrbuf, &CC->user, &ra, &view);
414 * The "created after <date/time>" heuristics depend on the happy coincidence
415 * that for a very long time we have used a unix timestamp as the room record's
416 * generation number (QRgen). When this module is merged into the master
417 * source tree we should rename QRgen to QR_create_time or something like that.
421 if (qrbuf->QRgen >= thetime) {
422 output_roomname_in_list_format(qrbuf, NNTP_LIST_ACTIVE, NULL);
429 // Implements the NEWGROUPS command
431 void nntp_newgroups(const char *cmd) {
433 * HACK: this works because the 5XX series error codes from citadel
434 * protocol will also be considered error codes by an NNTP client
436 if (CtdlAccessCheck(ac_logged_in_or_guest)) return;
439 char stringy_date[16];
440 char stringy_time[16];
441 char stringy_gmt[16];
445 extract_token(stringy_date, cmd, 1, ' ', sizeof stringy_date);
446 extract_token(stringy_time, cmd, 2, ' ', sizeof stringy_time);
447 extract_token(stringy_gmt, cmd, 3, ' ', sizeof stringy_gmt);
449 memset(&tm, 0, sizeof tm);
450 if (strlen(stringy_date) == 6) {
451 sscanf(stringy_date, "%2d%2d%2d", &tm.tm_year, &tm.tm_mon, &tm.tm_mday);
455 sscanf(stringy_date, "%4d%2d%2d", &tm.tm_year, &tm.tm_mon, &tm.tm_mday);
458 tm.tm_mon -= 1; // tm_mon is zero based (0=January)
459 tm.tm_isdst = (-1); // let the C library figure out whether DST is in effect
460 sscanf(stringy_time, "%2d%2d%2d", &tm.tm_hour, &tm.tm_min ,&tm.tm_sec);
461 thetime = mktime(&tm);
462 if (!strcasecmp(stringy_gmt, "GMT")) {
468 cprintf("231 list of new newsgroups follows\r\n");
469 CtdlGetUser(&CC->user, CC->curr_user);
470 CtdlForEachRoom(nntp_newgroups_backend, &thetime);
476 // Called once per room by nntp_list() to qualify and possibly output a single room
478 void nntp_list_backend(struct ctdlroom *qrbuf, void *data)
482 struct nntp_list_data *nld = (struct nntp_list_data *)data;
484 CtdlRoomAccess(qrbuf, &CC->user, &ra, &view);
486 output_roomname_in_list_format(qrbuf, nld->list_format, nld->wildmat_pattern);
492 // Implements the LIST commands
494 void nntp_list(const char *cmd) {
496 // HACK: this works because the 5XX series error codes from citadel
497 // protocol will also be considered error codes by an NNTP client
499 if (CtdlAccessCheck(ac_logged_in_or_guest)) return;
501 char list_format[64];
502 char wildmat_pattern[1024];
503 struct nntp_list_data nld;
505 extract_token(list_format, cmd, 1, ' ', sizeof list_format);
506 extract_token(wildmat_pattern, cmd, 2, ' ', sizeof wildmat_pattern);
508 if (strlen(wildmat_pattern) > 0) {
509 nld.wildmat_pattern = wildmat_pattern;
512 nld.wildmat_pattern = NULL;
515 if ( (strlen(cmd) < 6) || (!strcasecmp(list_format, "ACTIVE")) ) {
516 nld.list_format = NNTP_LIST_ACTIVE;
518 else if (!strcasecmp(list_format, "NEWSGROUPS")) {
519 nld.list_format = NNTP_LIST_NEWSGROUPS;
522 cprintf("501 syntax error , unsupported list format\r\n");
526 cprintf("215 list of newsgroups follows\r\n");
527 CtdlGetUser(&CC->user, CC->curr_user);
528 CtdlForEachRoom(nntp_list_backend, &nld);
534 // Implement HELP command.
536 void nntp_help(void) {
537 cprintf("100 This is the Citadel NNTP service.\r\n");
538 cprintf("RTFM http://www.ietf.org/rfc/rfc3977.txt\r\n");
544 // back end for the LISTGROUP command , called for each message number
546 void nntp_listgroup_backend(long msgnum, void *userdata) {
548 struct listgroup_range *lr = (struct listgroup_range *)userdata;
550 // check range if supplied
551 if (msgnum < lr->lo) return;
552 if ((lr->hi != 0) && (msgnum > lr->hi)) return;
554 cprintf("%ld\r\n", msgnum);
559 // Implements the GROUP and LISTGROUP commands
561 void nntp_group(const char *cmd) {
563 // HACK: this works because the 5XX series error codes from citadel
564 // protocol will also be considered error codes by an NNTP client
566 if (CtdlAccessCheck(ac_logged_in_or_guest)) return;
568 citnntp *nntpstate = (citnntp *) CC->session_specific_data;
570 char requested_group[1024];
571 char message_range[256];
574 char requested_room[ROOMNAMELEN];
575 char augmented_roomname[ROOMNAMELEN];
579 struct ctdlroom QRscratch;
582 struct listgroup_range lr;
584 extract_token(verb, cmd, 0, ' ', sizeof verb);
585 extract_token(requested_group, cmd, 1, ' ', sizeof requested_group);
586 extract_token(message_range, cmd, 2, ' ', sizeof message_range);
587 extract_token(range_lo, message_range, 0, '-', sizeof range_lo);
588 extract_token(range_hi, message_range, 1, '-', sizeof range_hi);
589 lr.lo = atoi(range_lo);
590 lr.hi = atoi(range_hi);
592 /* In LISTGROUP mode we can specify an empty name for 'currently selected' */
593 if ((!strcasecmp(verb, "LISTGROUP")) && (IsEmptyStr(requested_group))) {
594 room_to_newsgroup(requested_group, CC->room.QRname, sizeof requested_group);
597 /* First try a regular match */
598 newsgroup_to_room(requested_room, requested_group, sizeof requested_room);
599 c = CtdlGetRoom(&QRscratch, requested_room);
601 /* Then try a mailbox name match */
603 CtdlMailboxName(augmented_roomname, sizeof augmented_roomname, &CC->user, requested_room);
604 c = CtdlGetRoom(&QRscratch, augmented_roomname);
606 safestrncpy(requested_room, augmented_roomname, sizeof(requested_room));
610 /* If the room exists, check security/access */
612 /* See if there is an existing user/room relationship */
613 CtdlRoomAccess(&QRscratch, &CC->user, &ra, NULL);
615 /* normal clients have to pass through security */
621 /* Fail here if no such room */
623 cprintf("411 no such newsgroup\r\n");
629 * CtdlUserGoto() formally takes us to the desired room, happily returning
630 * the number of messages and number of new messages.
632 memcpy(&CC->room, &QRscratch, sizeof(struct ctdlroom));
633 CtdlUserGoto(NULL, 0, 0, &msgs, &new, &oldest, &newest);
634 cprintf("211 %d %ld %ld %s\r\n", msgs, oldest, newest, requested_group);
636 // If this is a GROUP command, set the "current article number" to zero, and then stop here.
637 if (!strcasecmp(verb, "GROUP")) {
638 nntpstate->current_article_number = oldest;
642 // If we get to this point we are running a LISTGROUP command. Fetch those message numbers.
643 CtdlForEachMessage(MSGS_ALL, 0L, NULL, NULL, NULL, nntp_listgroup_backend, &lr);
649 // Implements the MODE command
651 void nntp_mode(const char *cmd) {
655 extract_token(which_mode, cmd, 1, ' ', sizeof which_mode);
657 if (!strcasecmp(which_mode, "reader")) {
658 cprintf("201 Reader mode FIXME implement posting and change to 200\r\n");
661 cprintf("501 unknown mode\r\n");
667 // Implements the ARTICLE, HEAD, BODY, and STAT commands.
668 // (These commands all accept the same parameters; they differ only in how they output the retrieved message.)
670 void nntp_article(const char *cmd) {
672 * HACK: this works because the 5XX series error codes from citadel
673 * protocol will also be considered error codes by an NNTP client
675 if (CtdlAccessCheck(ac_logged_in_or_guest)) return;
677 citnntp *nntpstate = (citnntp *) CC->session_specific_data;
678 char which_command[16];
680 char requested_article[256];
681 long requested_msgnum = 0;
682 char *lb, *rb = NULL;
683 int must_change_currently_selected_article = 0;
685 // We're going to store one of these values in the variable 'acmd' so that
693 extract_token(which_command, cmd, 0, ' ', sizeof which_command);
695 if (!strcasecmp(which_command, "article")) {
698 else if (!strcasecmp(which_command, "head")) {
701 else if (!strcasecmp(which_command, "body")) {
704 else if (!strcasecmp(which_command, "stat")) {
708 cprintf("500 I'm afraid I can't do that.\r\n");
712 // Which NNTP command was issued, determines whether we will fetch headers, body, or both.
713 int headers_only = HEADERS_ALL;
714 if (acmd == HEAD) headers_only = HEADERS_FAST;
715 else if (acmd == BODY) headers_only = HEADERS_NONE;
716 else if (acmd == STAT) headers_only = HEADERS_FAST;
718 // now figure out what the client is asking for.
719 extract_token(requested_article, cmd, 1, ' ', sizeof requested_article);
720 lb = strchr(requested_article, '<');
721 rb = strchr(requested_article, '>');
722 requested_msgnum = atol(requested_article);
724 // If no article number or message-id is specified, the client wants the "currently selected article"
725 if (IsEmptyStr(requested_article)) {
726 if (nntpstate->current_article_number < 1) {
727 cprintf("420 No current article selected\r\n");
730 requested_msgnum = nntpstate->current_article_number;
731 must_change_currently_selected_article = 1;
732 // got it -- now fall through and keep going
735 // If the requested article is numeric, it maps directly to a message number. Good.
736 else if (requested_msgnum > 0) {
737 must_change_currently_selected_article = 1;
738 // good -- fall through and keep going
741 // If the requested article has angle brackets, the client wants a specific message-id.
742 // We don't know how to do that yet.
743 else if ( (lb != NULL) && (rb != NULL) && (lb < rb) ) {
744 must_change_currently_selected_article = 0;
745 cprintf("500 FIXME I don't know how to fetch by message-id yet.\r\n");
749 // Anything else is noncompliant gobbledygook and should die in a car fire.
751 must_change_currently_selected_article = 0;
752 cprintf("500 syntax error\r\n");
756 // At this point we know the message number of the "article" being requested.
757 // We have an awesome API call that does all the heavy lifting for us.
758 char *fetched_message_id = NULL;
759 CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
760 int fetch = CtdlOutputMsg(requested_msgnum,
761 MT_RFC822, // output in RFC822 format ... sort of
762 headers_only, // headers, body, or both?
763 0, // don't do Citadel protocol responses
765 NULL, // teh whole thing, not just a section
766 0, // no flags yet ... maybe new ones for Path: etc ?
769 &fetched_message_id // extract the message ID from the message as we go...
771 StrBuf *msgtext = CC->redirect_buffer;
772 CC->redirect_buffer = NULL;
774 if (fetch != om_ok) {
775 cprintf("423 no article with that number\r\n");
776 FreeStrBuf(&msgtext);
780 // RFC3977 6.2.1.2 specifes conditions under which the "currently selected article"
781 // MUST or MUST NOT be set to the message we just referenced.
782 if (must_change_currently_selected_article) {
783 nntpstate->current_article_number = requested_msgnum;
786 // Now give the client what it asked for.
787 if (acmd == ARTICLE) {
788 cprintf("220 %ld <%s>\r\n", requested_msgnum, fetched_message_id);
791 cprintf("221 %ld <%s>\r\n", requested_msgnum, fetched_message_id);
794 cprintf("222 %ld <%s>\r\n", requested_msgnum, fetched_message_id);
797 cprintf("223 %ld <%s>\r\n", requested_msgnum, fetched_message_id);
798 FreeStrBuf(&msgtext);
802 client_write(SKEY(msgtext));
803 cprintf(".\r\n"); // this protocol uses a dot terminator
804 FreeStrBuf(&msgtext);
805 if (fetched_message_id) free(fetched_message_id);
810 // Main command loop for NNTP server sessions.
812 void nntp_command_loop(void)
814 StrBuf *Cmd = NewStrBuf();
818 if (CtdlClientGetLine(Cmd) < 1) {
819 syslog(LOG_CRIT, "NNTP: client disconnected: ending session.\n");
820 CC->kill_me = KILLME_CLIENT_DISCONNECTED;
824 syslog(LOG_DEBUG, "NNTP: %s\n", ((!strncasecmp(ChrPtr(Cmd), "AUTHINFO", 8)) ? "AUTHINFO ..." : ChrPtr(Cmd)));
825 extract_token(cmdname, ChrPtr(Cmd), 0, ' ', sizeof cmdname);
827 // Rumpelstiltskin lookups are *awesome*
829 if (!strcasecmp(cmdname, "quit")) {
833 else if (!strcasecmp(cmdname, "help")) {
837 else if (!strcasecmp(cmdname, "capabilities")) {
841 else if (!strcasecmp(cmdname, "starttls")) {
845 else if (!strcasecmp(cmdname, "authinfo")) {
846 nntp_authinfo(ChrPtr(Cmd));
849 else if (!strcasecmp(cmdname, "newgroups")) {
850 nntp_newgroups(ChrPtr(Cmd));
853 else if (!strcasecmp(cmdname, "list")) {
854 nntp_list(ChrPtr(Cmd));
857 else if (!strcasecmp(cmdname, "group")) {
858 nntp_group(ChrPtr(Cmd));
861 else if (!strcasecmp(cmdname, "listgroup")) {
862 nntp_group(ChrPtr(Cmd));
865 else if (!strcasecmp(cmdname, "mode")) {
866 nntp_mode(ChrPtr(Cmd));
870 (!strcasecmp(cmdname, "article"))
871 || (!strcasecmp(cmdname, "head"))
872 || (!strcasecmp(cmdname, "body"))
873 || (!strcasecmp(cmdname, "stat"))
875 nntp_article(ChrPtr(Cmd));
879 cprintf("500 I'm afraid I can't do that.\r\n");
886 // ****************************************************************************
887 // MODULE INITIALIZATION STUFF
888 // ****************************************************************************
892 // This cleanup function blows away the temporary memory used by
895 void nntp_cleanup_function(void)
897 /* Don't do this stuff if this is not an NNTP session! */
898 if (CC->h_command_function != nntp_command_loop) return;
900 syslog(LOG_DEBUG, "Performing NNTP cleanup hook\n");
901 citnntp *nntpstate = (citnntp *) CC->session_specific_data;
902 if (nntpstate != NULL) {
908 const char *CitadelServiceNNTP="NNTP";
910 CTDL_MODULE_INIT(nntp)
914 CtdlRegisterServiceHook(119, // FIXME config.c_nntp_port,
922 CtdlRegisterServiceHook(563, // FIXME config.c_nntps_port,
930 CtdlRegisterCleanupHook(nntp_cleanup);
931 CtdlRegisterSessionHook(nntp_cleanup_function, EVT_STOP, PRIO_STOP + 250);
934 /* return our module name for the log */