--- /dev/null
+/*
+ * NNTP server module FIXME THIS IS NOT FINISHED
+ *
+ * Copyright (c) 2014 by the citadel.org team
+ *
+ * This program is open source software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include "sysdep.h"
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <termios.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <pwd.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <syslog.h>
+
+#if TIME_WITH_SYS_TIME
+# include <sys/time.h>
+# include <time.h>
+#else
+# if HAVE_SYS_TIME_H
+# include <sys/time.h>
+# else
+# include <time.h>
+# endif
+#endif
+
+#include <sys/wait.h>
+#include <ctype.h>
+#include <string.h>
+#include <limits.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <libcitadel.h>
+#include "citadel.h"
+#include "server.h"
+#include "citserver.h"
+#include "support.h"
+#include "config.h"
+#include "control.h"
+#include "user_ops.h"
+#include "room_ops.h"
+#include "database.h"
+#include "msgbase.h"
+#include "internet_addressing.h"
+#include "genstamp.h"
+#include "domain.h"
+#include "clientsocket.h"
+#include "locate_host.h"
+#include "citadel_dirs.h"
+#include "ctdl_module.h"
+#include "serv_nntp.h"
+
+extern long timezone;
+
+/****************** BEGIN UTILITY FUNCTIONS THAT COULD BE MOVED ELSEWHERE LATER **************/
+
+
+/*
+ * Tests whether the supplied string is a valid newsgroup name
+ * Returns true (nonzero) or false (0)
+ */
+int is_valid_newsgroup_name(char *name) {
+ char *ptr = name;
+ int has_a_letter = 0;
+
+ if (!ptr) return(0);
+ if (!strncasecmp(name, "ctdl.", 5)) return(0);
+
+ while (*ptr != 0) {
+
+ if (isalpha(ptr[0])) {
+ has_a_letter = 1;
+ }
+
+ if ( (isalnum(ptr[0]))
+ || (ptr[0] == '.')
+ || (ptr[0] == '+')
+ || (ptr[0] == '-')
+ ) {
+ ++ptr;
+ }
+ else {
+ return(0);
+ }
+ }
+ return(has_a_letter);
+}
+
+
+
+/*
+ * Convert a Citadel room name to a valid newsgroup name
+ */
+void room_to_newsgroup(char *target, char *source, size_t target_size) {
+
+ if (!target) return;
+ if (!source) return;
+
+ if (is_valid_newsgroup_name(source)) {
+ strncpy(target, source, target_size);
+ return;
+ }
+
+ strcpy(target, "ctdl.");
+ int len = 5;
+ char *ptr = source;
+ char ch;
+
+ while (ch=*ptr++, ch!=0) {
+ if (len >= target_size) return;
+ if ( (isalnum(ch))
+ || (ch == '.')
+ || (ch == '-')
+ ) {
+ target[len++] = ch;
+ target[len] = 0;
+ }
+ else {
+ target[len++] = '+' ;
+ sprintf(&target[len], "%02x", ch);
+ len += 2;
+ target[len] = 0;
+ }
+ }
+}
+
+
+/*
+ * Convert a newsgroup name to a Citadel room name.
+ * This function recognizes names converted with room_to_newsgroup() and restores them with full fidelity.
+ */
+void newsgroup_to_room(char *target, char *source, size_t target_size) {
+
+ if (!target) return;
+ if (!source) return;
+
+ if (strncasecmp(source, "ctdl.", 5)) { // not a converted room name; pass through as-is
+ strncpy(target, source, target_size);
+ return;
+ }
+
+ target[0] = 0;
+ int len = 0;
+ char *ptr = &source[5];
+ char ch;
+
+ while (ch=*ptr++, ch!=0) {
+ if (len >= target_size) return;
+ if (ch == '+') {
+ char hex[3];
+ long digit;
+ hex[0] = *ptr++;
+ hex[1] = *ptr++;
+ hex[2] = 0;
+ digit = strtol(hex, NULL, 16);
+ ch = (char)digit;
+ }
+ target[len++] = ch;
+ target[len] = 0;
+ }
+}
+
+
+/****************** END UTILITY FUNCTIONS THAT COULD BE MOVED ELSEWHERE LATER **************/
+
+
+
+/*
+ * Here's where our NNTP session begins its happy day.
+ */
+void nntp_greeting(void)
+{
+ strcpy(CC->cs_clientname, "NNTP session");
+ CC->cs_flags |= CS_STEALTH;
+
+ /* CC->session_specific_data = malloc(sizeof(citnntp));
+ memset(NNTP, 0, sizeof(citnntp));
+ */
+
+ if (CC->nologin==1) {
+ cprintf("451 Too many connections are already open; please try again later.\r\n");
+ CC->kill_me = KILLME_MAX_SESSIONS_EXCEEDED;
+ return;
+ }
+
+ /* Note: the FQDN *must* appear as the first thing after the 220 code.
+ * Some clients (including citmail.c) depend on it being there.
+ */
+ cprintf("200 %s NNTP Citadel server is not finished yet\r\n", config.c_fqdn);
+}
+
+
+/*
+ * NNTPS is just like NNTP, except it goes crypto right away.
+ */
+void nntps_greeting(void) {
+ CtdlModuleStartCryptoMsgs(NULL, NULL, NULL);
+#ifdef HAVE_OPENSSL
+ if (!CC->redirect_ssl) CC->kill_me = KILLME_NO_CRYPTO; /* kill session if no crypto */
+#endif
+ nntp_greeting();
+}
+
+
+
+/*
+ * implements the STARTTLS command
+ */
+void nntp_starttls(void)
+{
+ char ok_response[SIZ];
+ char nosup_response[SIZ];
+ char error_response[SIZ];
+
+ sprintf(ok_response, "382 Begin TLS negotiation now\r\n");
+ sprintf(nosup_response, "502 Can not initiate TLS negotiation\r\n");
+ sprintf(error_response, "580 Internal error\r\n");
+ CtdlModuleStartCryptoMsgs(ok_response, nosup_response, error_response);
+}
+
+
+void nntp_noop(void)
+{
+ cprintf("250 NOOP\r\n");
+}
+
+
+void nntp_capabilities(void)
+{
+ cprintf("101 Capability list:\r\n");
+#ifdef HAVE_OPENSSL
+ cprintf("STARTTLS\r\n");
+#endif
+ if (!CC->logged_in) {
+ cprintf("AUTHINFO USER\r\n");
+ }
+ cprintf(".\r\n");
+}
+
+
+void nntp_quit(void)
+{
+ cprintf("221 Goodbye...\r\n");
+ CC->kill_me = KILLME_CLIENT_LOGGED_OUT;
+}
+
+
+void nntp_cleanup(void)
+{
+ /* nothing here yet */
+}
+
+
+
+/*
+ * Implements the AUTHINFO USER command (RFC 4643)
+ */
+void nntp_authinfo_user(const char *username)
+{
+ int a = CtdlLoginExistingUser(NULL, username);
+ switch (a) {
+ case login_already_logged_in:
+ cprintf("482 Already logged in\r\n");
+ return;
+ case login_too_many_users:
+ cprintf("481 Too many users are already online (maximum is %d)\r\n", config.c_maxsessions);
+ return;
+ case login_ok:
+ cprintf("381 Password required for %s\r\n", CC->curr_user);
+ return;
+ case login_not_found:
+ cprintf("481 %s not found\r\n", username);
+ return;
+ default:
+ cprintf("502 Internal error\r\n");
+ }
+}
+
+
+/*
+ * Implements the AUTHINFO PASS command (RFC 4643)
+ */
+void nntp_authinfo_pass(const char *buf)
+{
+ int a;
+
+ a = CtdlTryPassword(buf, strlen(buf));
+
+ switch (a) {
+ case pass_already_logged_in:
+ cprintf("482 Already logged in\r\n");
+ return;
+ case pass_no_user:
+ cprintf("482 Authentication commands issued out of sequence\r\n");
+ return;
+ case pass_wrong_password:
+ cprintf("481 Authentication failed\r\n");
+ return;
+ case pass_ok:
+ cprintf("281 Authentication accepted\r\n");
+ return;
+ }
+}
+
+
+
+/*
+ * Implements the AUTHINFO extension (RFC 4643) in USER/PASS mode
+ */
+void nntp_authinfo(const char *cmd) {
+
+ if (!strncasecmp(cmd, "authinfo user ", 14)) {
+ nntp_authinfo_user(&cmd[14]);
+ }
+
+ else if (!strncasecmp(cmd, "authinfo pass ", 14)) {
+ nntp_authinfo_pass(&cmd[14]);
+ }
+
+ else {
+ cprintf("502 command unavailable\r\n");
+ }
+}
+
+
+/*
+ * Utility function to fetch the current list of message numbers in a room
+ */
+struct nntp_msglist nntp_fetch_msglist(struct ctdlroom *qrbuf) {
+ struct nntp_msglist nm;
+ struct cdbdata *cdbfr;
+
+ cdbfr = cdb_fetch(CDB_MSGLISTS, &qrbuf->QRnumber, sizeof(long));
+ if (cdbfr != NULL) {
+ nm.msgnums = (long*)cdbfr->ptr;
+ cdbfr->ptr = NULL;
+ nm.num_msgs = cdbfr->len / sizeof(long);
+ cdbfr->len = 0;
+ cdb_free(cdbfr);
+ } else {
+ nm.num_msgs = 0;
+ nm.msgnums = NULL;
+ }
+ return(nm);
+}
+
+
+
+/*
+ * Various output formats for the LIST commands
+ */
+enum {
+ NNTP_LIST_ACTIVE,
+ NNTP_LIST_ACTIVE_TIMES,
+ NNTP_LIST_DISTRIB_PATS,
+ NNTP_LIST_HEADERS,
+ NNTP_LIST_NEWSGROUPS,
+ NNTP_LIST_OVERVIEW_FMT
+};
+
+
+/*
+ * Output a room name (newsgroup name) in formats required for LIST and NEWGROUPS command
+ */
+void output_roomname_in_list_format(struct ctdlroom *qrbuf, int which_format) {
+ char n_name[1024];
+ struct nntp_msglist nm;
+ long low_water_mark = 0;
+ long high_water_mark = 0;
+
+ room_to_newsgroup(n_name, qrbuf->QRname, sizeof n_name);
+ nm = nntp_fetch_msglist(qrbuf);
+ if ((nm.num_msgs > 0) && (nm.msgnums != NULL)) {
+ low_water_mark = nm.msgnums[0];
+ high_water_mark = nm.msgnums[nm.num_msgs - 1];
+ }
+
+ switch(which_format) {
+ case NNTP_LIST_ACTIVE:
+ // FIXME we have hardcoded "n" for "no posting allowed" -- fix when we add posting
+ cprintf("%s %ld %ld n\r\n", n_name, high_water_mark, low_water_mark);
+ break;
+ case NNTP_LIST_NEWSGROUPS:
+ cprintf("%s %s\r\n", n_name, qrbuf->QRname);
+ break;
+ }
+ // FIXME do all the other formats, bitch
+
+ if (nm.msgnums != NULL) {
+ free(nm.msgnums);
+ }
+}
+
+
+
+/*
+ * Called once per room by nntp_newgroups() to qualify and possibly output a single room
+ */
+void nntp_newgroups_backend(struct ctdlroom *qrbuf, void *data)
+{
+ int ra;
+ int view;
+ time_t thetime = *(time_t *)data;
+
+ CtdlRoomAccess(qrbuf, &CC->user, &ra, &view);
+
+ /*
+ * The "created after <date/time>" heuristics depend on the happy coincidence
+ * that for a very long time we have used a unix timestamp as the room record's
+ * generation number (QRgen). When this module is merged into the master
+ * source tree we should rename QRgen to QR_create_time or something like that.
+ */
+
+ if (ra & UA_KNOWN) {
+ if (qrbuf->QRgen >= thetime) {
+ output_roomname_in_list_format(qrbuf, NNTP_LIST_ACTIVE);
+ }
+ }
+}
+
+
+/*
+ * Implements the NEWGROUPS command
+ */
+void nntp_newgroups(const char *cmd) {
+ /*
+ * HACK: this works because the 5XX series error codes from citadel
+ * protocol will also be considered error codes by an NNTP client
+ */
+ if (CtdlAccessCheck(ac_logged_in_or_guest)) return;
+
+
+ char stringy_date[16];
+ char stringy_time[16];
+ char stringy_gmt[16];
+ struct tm tm;
+ time_t thetime;
+
+ extract_token(stringy_date, cmd, 1, ' ', sizeof stringy_date);
+ extract_token(stringy_time, cmd, 2, ' ', sizeof stringy_time);
+ extract_token(stringy_gmt, cmd, 3, ' ', sizeof stringy_gmt);
+
+ memset(&tm, 0, sizeof tm);
+ if (strlen(stringy_date) == 6) {
+ sscanf(stringy_date, "%2d%2d%2d", &tm.tm_year, &tm.tm_mon, &tm.tm_mday);
+ tm.tm_year += 100;
+ }
+ else {
+ sscanf(stringy_date, "%4d%2d%2d", &tm.tm_year, &tm.tm_mon, &tm.tm_mday);
+ tm.tm_year -= 1900;
+ }
+ tm.tm_mon -= 1; // tm_mon is zero based (0=January)
+ tm.tm_isdst = (-1); // let the C library figure out whether DST is in effect
+ sscanf(stringy_time, "%2d%2d%2d", &tm.tm_hour, &tm.tm_min ,&tm.tm_sec);
+ thetime = mktime(&tm);
+ if (!strcasecmp(stringy_gmt, "GMT")) {
+ tzset();
+ thetime += timezone;
+ }
+
+
+ cprintf("231 list of new newsgroups follows\r\n");
+ CtdlGetUser(&CC->user, CC->curr_user);
+ CtdlForEachRoom(nntp_newgroups_backend, &thetime);
+ cprintf(".\r\n");
+}
+
+
+/*
+ * Called once per room by nntp_list() to qualify and possibly output a single room
+ */
+void nntp_list_backend(struct ctdlroom *qrbuf, void *data)
+{
+ int ra;
+ int view;
+ struct nntp_list_data *nld = (struct nntp_list_data *)data;
+
+ CtdlRoomAccess(qrbuf, &CC->user, &ra, &view);
+ if (ra & UA_KNOWN) {
+ output_roomname_in_list_format(qrbuf, nld->list_format);
+ }
+}
+
+
+/*
+ * Implements the LIST commands
+ */
+void nntp_list(const char *cmd) {
+ /*
+ * HACK: this works because the 5XX series error codes from citadel
+ * protocol will also be considered error codes by an NNTP client
+ */
+ if (CtdlAccessCheck(ac_logged_in_or_guest)) return;
+
+ char list_format[64];
+ char wildmat[1024];
+ struct nntp_list_data nld;
+
+ extract_token(list_format, cmd, 1, ' ', sizeof list_format);
+ extract_token(wildmat, cmd, 2, ' ', sizeof wildmat);
+
+ if ( (strlen(cmd) < 6) || (!strcasecmp(list_format, "ACTIVE")) ) {
+ nld.list_format = NNTP_LIST_ACTIVE;
+ }
+ else if (!strcasecmp(list_format, "NEWSGROUPS")) {
+ nld.list_format = NNTP_LIST_NEWSGROUPS;
+ }
+ else {
+ cprintf("501 syntax error , unsupported list format\r\n");
+ return;
+ }
+ // FIXME do all of the other variants, bitch
+
+
+ cprintf("231 list of newsgroups follows\r\n");
+ CtdlGetUser(&CC->user, CC->curr_user);
+ CtdlForEachRoom(nntp_list_backend, &nld);
+ cprintf(".\r\n");
+}
+
+
+/*
+ * Main command loop for NNTP server sessions.
+ */
+void nntp_command_loop(void)
+{
+ StrBuf *Cmd = NewStrBuf();
+ char cmdname[16];
+
+ time(&CC->lastcmd);
+ if (CtdlClientGetLine(Cmd) < 1) {
+ syslog(LOG_CRIT, "NNTP: client disconnected: ending session.\n");
+ CC->kill_me = KILLME_CLIENT_DISCONNECTED;
+ FreeStrBuf(&Cmd);
+ return;
+ }
+ syslog(LOG_DEBUG, "NNTP server: %s\n", ChrPtr(Cmd));
+ extract_token(cmdname, ChrPtr(Cmd), 0, ' ', sizeof cmdname);
+
+ /*
+ * Rumpelstiltskin lookups are awesome
+ */
+
+ if (!strcasecmp(cmdname, "quit")) {
+ nntp_quit();
+ }
+
+ else if (!strcasecmp(cmdname, "capabilities")) {
+ nntp_capabilities();
+ }
+
+ else if (!strcasecmp(cmdname, "starttls")) {
+ nntp_starttls();
+ }
+
+ else if (!strcasecmp(cmdname, "noop")) {
+ nntp_noop();
+ }
+
+ else if (!strcasecmp(cmdname, "authinfo")) {
+ nntp_authinfo(ChrPtr(Cmd));
+ }
+
+ else if (!strcasecmp(cmdname, "newgroups")) {
+ nntp_newgroups(ChrPtr(Cmd));
+ }
+
+ else if (!strcasecmp(cmdname, "list")) {
+ nntp_list(ChrPtr(Cmd));
+ }
+
+ else {
+ cprintf("500 I'm afraid I can't do that.\r\n");
+ }
+
+ FreeStrBuf(&Cmd);
+}
+
+
+/*****************************************************************************/
+/* MODULE INITIALIZATION STUFF */
+/*****************************************************************************/
+
+
+/*
+ * This cleanup function blows away the temporary memory used by
+ * the NNTP server.
+ */
+void nntp_cleanup_function(void)
+{
+ /* Don't do this stuff if this is not an NNTP session! */
+ if (CC->h_command_function != nntp_command_loop) return;
+
+ syslog(LOG_DEBUG, "Performing NNTP cleanup hook\n");
+}
+
+const char *CitadelServiceNNTP="NNTP";
+
+CTDL_MODULE_INIT(nntp)
+{
+ if (!threading)
+ {
+ CtdlRegisterServiceHook(119, // FIXME config.c_nntp_port,
+ NULL,
+ nntp_greeting,
+ nntp_command_loop,
+ NULL,
+ CitadelServiceNNTP);
+
+#ifdef HAVE_OPENSSL
+ CtdlRegisterServiceHook(563, // FIXME config.c_nntps_port,
+ NULL,
+ nntps_greeting,
+ nntp_command_loop,
+ NULL,
+ CitadelServiceNNTP);
+#endif
+
+ CtdlRegisterCleanupHook(nntp_cleanup);
+ CtdlRegisterSessionHook(nntp_cleanup_function, EVT_STOP, PRIO_STOP + 250);
+ }
+
+ /* return our module name for the log */
+ return "nntp";
+}
+
projects / citadel.git / commitdiff