+/*
+ * A server-side module for Citadel designed to filter idiots off the network.
+ *
+ * Copyright (c) 2002-2009 by the citadel.org team
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "sysdep.h"
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <pwd.h>
+#include <errno.h>
+#include <sys/types.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 <string.h>
+#include <limits.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 "database.h"
+#include "msgbase.h"
+
+
+#include "ctdl_module.h"
+
+typedef struct FilterList FilterList;
+
+struct FilterList {
+ FilterList *next;
+ char fl_user[SIZ];
+ char fl_room[SIZ];
+ char fl_node[SIZ];
+};
+
+struct FilterList *filterlist = NULL;
+
+/*
+ * Keep track of what messages to reject
+ */
+FilterList *load_filter_list(void) {
+ char *serialized_list = NULL;
+ int i;
+ char buf[SIZ];
+ FilterList *newlist = NULL;
+ FilterList *nptr;
+
+ serialized_list = CtdlGetSysConfig(FILTERLIST);
+ if (serialized_list == NULL) return(NULL); /* if null, no entries */
+
+ /* Use the string tokenizer to grab one line at a time */
+ for (i=0; i<num_tokens(serialized_list, '\n'); ++i) {
+ extract_token(buf, serialized_list, i, '\n', sizeof buf);
+ nptr = (FilterList *) malloc(sizeof(FilterList));
+ extract_token(nptr->fl_user, buf, 0, '|', sizeof nptr->fl_user);
+ striplt(nptr->fl_user);
+ extract_token(nptr->fl_room, buf, 1, '|', sizeof nptr->fl_room);
+ striplt(nptr->fl_room);
+ extract_token(nptr->fl_node, buf, 2, '|', sizeof nptr->fl_node);
+ striplt(nptr->fl_node);
+
+ /* Cowardly refuse to add an any/any/any entry that would
+ * end up filtering every single message.
+ */
+ if (IsEmptyStr(nptr->fl_user) &&
+ IsEmptyStr(nptr->fl_room) &&
+ IsEmptyStr(nptr->fl_node)) {
+ free(nptr);
+ }
+ else {
+ nptr->next = newlist;
+ newlist = nptr;
+ }
+ }
+
+ free(serialized_list);
+ return newlist;
+}
+
+
+void free_filter_list(FilterList *fl) {
+ if (fl == NULL) return;
+ free_filter_list(fl->next);
+ free(fl);
+}
+
+void free_netfilter_list(void)
+{
+ free_filter_list(filterlist);
+ filterlist = NULL;
+}
+
+void load_network_filter_list(void)
+{
+ filterlist = load_filter_list();
+}
+
+
+/*
+ * This handler detects whether an incoming network message is from some
+ * moron user who the site operator has elected to filter out. If a match
+ * is found, the message is rejected.
+ */
+int filter_the_idiots(struct CtdlMessage *msg, char *target_room) {
+ FilterList *fptr;
+ int zap_user = 0;
+ int zap_room = 0;
+ int zap_node = 0;
+
+ if ( (msg == NULL) || (filterlist == NULL) ) {
+ return(0);
+ }
+
+ for (fptr = filterlist; fptr != NULL; fptr = fptr->next) {
+
+ zap_user = 0;
+ zap_room = 0;
+ zap_node = 0;
+
+ if (msg->cm_fields['A'] != NULL) {
+ if ( (!strcasecmp(msg->cm_fields['A'], fptr->fl_user))
+ || (fptr->fl_user[0] == 0) ) {
+ zap_user = 1;
+ }
+ }
+
+ if (msg->cm_fields['C'] != NULL) {
+ if ( (!strcasecmp(msg->cm_fields['C'], fptr->fl_room))
+ || (fptr->fl_room[0] == 0) ) {
+ zap_room = 1;
+ }
+ }
+
+ if (msg->cm_fields['O'] != NULL) {
+ if ( (!strcasecmp(msg->cm_fields['O'], fptr->fl_room))
+ || (fptr->fl_room[0] == 0) ) {
+ zap_room = 1;
+ }
+ }
+
+ if (msg->cm_fields['N'] != NULL) {
+ if ( (!strcasecmp(msg->cm_fields['N'], fptr->fl_node))
+ || (fptr->fl_node[0] == 0) ) {
+ zap_node = 1;
+ }
+ }
+
+ if (zap_user + zap_room + zap_node == 3) return(1);
+
+ }
+
+ return(0);
+}
+
+
+CTDL_MODULE_INIT(netfilter)
+{
+ if (!threading)
+ {
+ CtdlRegisterNetprocHook(filter_the_idiots);
+ }
+
+ /* return our module name for the log */
+ return "netfilter";
+}