paulo@0: /*
paulo@0:  * $Id: gt_ban.c,v 1.7 2004/01/29 07:50:25 hipnod Exp $
paulo@0:  *
paulo@0:  * Copyright (C) 2003 giFT project (gift.sourceforge.net)
paulo@0:  *
paulo@0:  * This program is free software; you can redistribute it and/or modify it
paulo@0:  * under the terms of the GNU General Public License as published by the
paulo@0:  * Free Software Foundation; either version 2, or (at your option) any
paulo@0:  * later version.
paulo@0:  *
paulo@0:  * This program is distributed in the hope that it will be useful, but
paulo@0:  * WITHOUT ANY WARRANTY; without even the implied warranty of
paulo@0:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
paulo@0:  * General Public License for more details.
paulo@0:  */
paulo@0: 
paulo@0: #include "gt_gnutella.h"
paulo@0: 
paulo@0: #include "gt_conf.h"
paulo@0: #include "gt_ban.h"
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: /* mask of bits that determines which bucket a ban goes into */
paulo@0: #define  INDEX_MASK              (0xff000000)
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: typedef struct ban_ipv4
paulo@0: {
paulo@0: 	in_addr_t     ipv4;
paulo@0: 	uint32_t      netmask;
paulo@0: } ban_ipv4_t;
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: /* ban list organize by the first 8 bits */
paulo@0: static Dataset *ipv4_ban_list;
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: static char *net_mask_str (uint32_t netmask)
paulo@0: {
paulo@0: 	static char buf[128];
paulo@0: 
paulo@0: 	snprintf (buf, sizeof (buf) - 1, "%d.%d.%d.%d",
paulo@0: 	          (netmask & 0xff000000) >> 24,
paulo@0: 	          (netmask & 0x00ff0000) >> 16,
paulo@0: 	          (netmask & 0x0000ff00) >> 8,
paulo@0: 	          (netmask & 0x000000ff));
paulo@0: 
paulo@0: 	return buf;
paulo@0: }
paulo@0: 
paulo@0: static uint32_t net_mask_bin (char *netmask)
paulo@0: {
paulo@0: 	uint32_t a[4];
paulo@0: 
paulo@0: 	if (!netmask)
paulo@0: 		return 0xFFFFffff;
paulo@0: 
paulo@0: 	if (sscanf (netmask, "%d.%d.%d.%d", &a[0], &a[1], &a[2], &a[3]) != 4)
paulo@0: 		return 0xFFFFffff;
paulo@0: 
paulo@0: 	return (a[0] << 24) | (a[1] << 16) | (a[2] << 8) | a[3];
paulo@0: }
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: /* 
paulo@0:  * Returns 0 if ban 'b' is contained within ban 'a'.
paulo@0:  */
paulo@0: static int find_superset_ban (ban_ipv4_t *a, ban_ipv4_t *b)
paulo@0: {
paulo@0: 	uint32_t sig1 = a->ipv4 & a->netmask;
paulo@0: 	uint32_t sig2 = b->ipv4 & b->netmask;
paulo@0: 
paulo@0: 	/*
paulo@0: 	 * If there are no bits in the significant address portions
paulo@0: 	 * that contradict within _a_'s netmask, then ban _b_ is a
paulo@0: 	 * subset of _a_.
paulo@0: 	 */
paulo@0: 	return ((sig2 ^ sig1) & a->netmask);
paulo@0: }
paulo@0: 
paulo@0: static void log_dup (ban_ipv4_t *orig_ban, ban_ipv4_t *b)
paulo@0: {
paulo@0: 	char  *ip1, *ip2;
paulo@0: 	char  *n1,  *n2;
paulo@0: 
paulo@0: 	if (!orig_ban || !b)
paulo@0: 		return;
paulo@0: 
paulo@0: 	n1  = STRDUP (net_mask_str (b->netmask));
paulo@0: 	ip1 = STRDUP (net_ip_str (htonl (b->ipv4)));
paulo@0: 	n2  = net_mask_str (orig_ban->netmask);
paulo@0: 	ip2 = net_ip_str (htonl (orig_ban->ipv4));
paulo@0: 
paulo@0: 	if (BAN_DEBUG)
paulo@0: 		GT->dbg (GT, "ban %s/%s is a subset of %s/%s", ip1, n1, ip2, n2);
paulo@0: 
paulo@0: 	free (ip1); 
paulo@0: 	free (n1);
paulo@0: }
paulo@0: 
paulo@0: BOOL gt_ban_ipv4_add (in_addr_t address, uint32_t netmask)
paulo@0: {
paulo@0: 	uint32_t     prefix;
paulo@0: 	List        *list;
paulo@0: 	List        *orig;
paulo@0: 	ban_ipv4_t  *ban;
paulo@0: 
paulo@0: 	if (!(ban = MALLOC (sizeof (ban_ipv4_t))))
paulo@0: 		return FALSE;
paulo@0: 
paulo@0: 	address = ntohl (address);
paulo@0: 
paulo@0: 	ban->ipv4    = address;
paulo@0: 	ban->netmask = netmask | INDEX_MASK;  /* ensure we have at least 8 bits */
paulo@0: 
paulo@0: 	prefix = address & INDEX_MASK;
paulo@0: 
paulo@0: 	list = dataset_lookup (ipv4_ban_list, &prefix, sizeof (prefix));
paulo@0: 
paulo@0: 	if ((orig = list_find_custom (list, ban, (ListForeachFunc)find_superset_ban)))
paulo@0: 	{
paulo@0: 		log_dup (list_nth_data (orig, 0), ban);
paulo@0: 		free (ban);
paulo@0: 		return TRUE;
paulo@0: 	}
paulo@0: 
paulo@0: 	list = list_prepend (list, ban);
paulo@0: 
paulo@0: 	if (!dataset_insert (&ipv4_ban_list, &prefix, sizeof (prefix), list, 0))
paulo@0: 		return FALSE;
paulo@0: 
paulo@0: 	if (BAN_DEBUG)
paulo@0: 	{
paulo@0: 		GT->dbg (GT, "*!*@%s/%s", net_ip_str (htonl (address)),
paulo@0: 		         net_mask_str (netmask));
paulo@0: 	}
paulo@0: 
paulo@0: 	return TRUE;
paulo@0: }
paulo@0: 
paulo@0: BOOL gt_ban_ipv4_is_banned (in_addr_t address)
paulo@0: {
paulo@0: 	uint32_t    prefix;
paulo@0: 	List       *list;
paulo@0: 	ban_ipv4_t  ban;
paulo@0: 
paulo@0: 	address = ntohl (address);
paulo@0: 	prefix  = address & INDEX_MASK;
paulo@0: 
paulo@0: 	if (!(list = dataset_lookup (ipv4_ban_list, &prefix, sizeof (prefix))))
paulo@0: 		return FALSE;
paulo@0: 
paulo@0: 	ban.ipv4    = address;
paulo@0: 	ban.netmask = 0xFFFFffff;
paulo@0: 
paulo@0: 	if (list_find_custom (list, &ban, (ListForeachFunc)find_superset_ban))
paulo@0: 		return TRUE;
paulo@0: 		
paulo@0: 	return FALSE;
paulo@0: }
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: static BOOL load_hostiles_txt (char *hostiles_filename)
paulo@0: {
paulo@0: 	FILE  *f;
paulo@0: 	char  *hostiles_path;
paulo@0: 	char  *buf = NULL;
paulo@0: 	char  *p;
paulo@0: 
paulo@0: 	hostiles_path = gift_conf_path ("%s/%s", GT->name, hostiles_filename);
paulo@0: 
paulo@0: 	if (!(f = fopen (hostiles_path, "r")))
paulo@0: 		return FALSE;
paulo@0: 
paulo@0: 	while (file_read_line (f, &buf))
paulo@0: 	{
paulo@0: 		in_addr_t  ipv4;
paulo@0: 		uint32_t   netmask;
paulo@0: 		char      *ipv4_str;
paulo@0: 		char      *mask_str;
paulo@0: 
paulo@0: 		p = buf;
paulo@0: 
paulo@0: 		/* divide the string into two sides */
paulo@0: 		ipv4_str = string_sep (&p, "/");
paulo@0: 		mask_str = p;
paulo@0: 
paulo@0: 		if (!ipv4_str)
paulo@0: 			continue;
paulo@0: 
paulo@0: 		netmask = net_mask_bin (mask_str);
paulo@0: 		ipv4    = net_ip       (ipv4_str);
paulo@0: 
paulo@0: 		if (!ipv4 || ipv4 == INADDR_NONE)
paulo@0: 			continue;
paulo@0: 
paulo@0: 		gt_ban_ipv4_add (ipv4, netmask);
paulo@0: 	}
paulo@0: 
paulo@0: 	fclose (f);
paulo@0: 	return TRUE;
paulo@0: }
paulo@0: 
paulo@0: void gt_ban_init (void)
paulo@0: {
paulo@0: 	ipv4_ban_list = dataset_new (DATASET_HASH);
paulo@0: 
paulo@0: 	if (!gt_config_load_file ("Gnutella/hostiles.txt", TRUE, FALSE))
paulo@0: 		GT->warn (GT, "couldn't load \"hostiles.txt\"");
paulo@0: 
paulo@0: 	load_hostiles_txt ("hostiles.txt");
paulo@0: #ifndef WIN32
paulo@0: 	load_hostiles_txt ("Hostiles.txt"); /* case-sensitivite blah */
paulo@0: #endif
paulo@0: }
paulo@0: 
paulo@0: static int free_ban (ban_ipv4_t *ban, void *udata)
paulo@0: {
paulo@0: 	free (ban);
paulo@0: 	return TRUE;
paulo@0: }
paulo@0: 
paulo@0: static int cleanup_lists (ds_data_t *data, ds_data_t *value, void *udata)
paulo@0: {
paulo@0: 	List *list = value->data;
paulo@0: 	list_foreach_remove (list, (ListForeachFunc)free_ban, NULL);
paulo@0: 	return DS_CONTINUE | DS_REMOVE;
paulo@0: }
paulo@0: 
paulo@0: void gt_ban_cleanup (void)
paulo@0: {
paulo@0: 	dataset_foreach_ex (ipv4_ban_list, DS_FOREACH_EX(cleanup_lists), NULL);
paulo@0: 	dataset_clear (ipv4_ban_list);
paulo@0: 	ipv4_ban_list = NULL;
paulo@0: }