/* src/bandbi.c
 * An interface to the ban db.
 *
 * Copyright (C) 2006 Lee Hardy <lee -at- leeh.co.uk>
 * Copyright (C) 2006 ircd-ratbox development team
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * 1.Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 * 2.Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * 3.The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
#include "stdinc.h"
#include "rb_lib.h"
#include "client.h"
#include "s_conf.h"
#include "logger.h"
#include "match.h"
#include "bandbi.h"
#include "parse.h"
#include "channel.h"
#include "hostmask.h"
#include "hash.h"
#include "s_newconf.h"
#include "reject.h"
#include "send.h"
#include "ircd.h"
#include "msg.h"	/* XXX: MAXPARA */
#include "operhash.h"

static void
bandb_handle_failure(rb_helper *helper, char **parv, int parc) __noreturn;

static char bandb_add_letter[LAST_BANDB_TYPE] = {
	'K', 'D', 'X', 'R'
};

rb_dlink_list bandb_pending;

static rb_helper *bandb_helper;
static int start_bandb(void);

static void bandb_parse(rb_helper *);
static void bandb_restart_cb(rb_helper *);
static char *bandb_path;

void
init_bandb(void)
{
	if(start_bandb())
	{
		ilog(L_MAIN, "Unable to start bandb helper: %s", strerror(errno));
		exit(0);
	}
}


static int
start_bandb(void)
{
	char fullpath[PATH_MAX + 1];

	rb_setenv("BANDB_DBPATH", ircd_paths[IRCD_PATH_BANDB], 1);
	if(bandb_path == NULL)
	{
		snprintf(fullpath, sizeof(fullpath), "%s/bandb", ircd_paths[IRCD_PATH_LIBEXEC]);

		if(access(fullpath, X_OK) == -1)
		{
			snprintf(fullpath, sizeof(fullpath), "%s/bin/bandb", ConfigFileEntry.dpath);

			if(access(fullpath, X_OK) == -1)
			{
				ilog(L_MAIN,
				     "Unable to execute bandb in %s or %s/bin",
				     ircd_paths[IRCD_PATH_LIBEXEC], ConfigFileEntry.dpath);
				return 0;
			}
		}
		bandb_path = rb_strdup(fullpath);
	}


	bandb_helper = rb_helper_start("bandb", bandb_path, bandb_parse, bandb_restart_cb);

	if(bandb_helper == NULL)
	{
		ilog(L_MAIN, "Unable to start bandb: %s", strerror(errno));
		sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Unable to start bandb helper: %s",
				     strerror(errno));
		return 1;
	}

	ilog(L_MAIN, "bandb helper started");
	sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "bandb helper started");
	rb_helper_run(bandb_helper);
	return 0;
}

void
bandb_add(bandb_type type, struct Client *source_p, const char *mask1,
	  const char *mask2, const char *reason, const char *oper_reason, int perm)
{
	if(bandb_helper == NULL)
		return;

	static char buf[BUFSIZE];

	snprintf(buf, sizeof(buf), "%c %s ", bandb_add_letter[type], mask1);

	if(!EmptyString(mask2))
		rb_snprintf_append(buf, sizeof(buf), "%s ", mask2);

	rb_snprintf_append(buf, sizeof(buf), "%s %ld %d :%s",
			   get_oper_name(source_p), (long int)rb_current_time(), perm, reason);

	if(!EmptyString(oper_reason))
		rb_snprintf_append(buf, sizeof(buf), "|%s", oper_reason);

	rb_helper_write(bandb_helper, "%s", buf);
}

static char bandb_del_letter[LAST_BANDB_TYPE] = {
	'k', 'd', 'x', 'r'
};

void
bandb_del(bandb_type type, const char *mask1, const char *mask2)
{
	if(bandb_helper == NULL)
		return;

	static char buf[BUFSIZE];

	buf[0] = '\0';

	rb_snprintf_append(buf, sizeof(buf), "%c %s", bandb_del_letter[type], mask1);

	if(!EmptyString(mask2))
		rb_snprintf_append(buf, sizeof(buf), " %s", mask2);

	rb_helper_write(bandb_helper, "%s", buf);
}

static void
bandb_handle_ban(char *parv[], int parc)
{
	struct ConfItem *aconf;
	char *p;
	int para = 1;

	aconf = make_conf();
	aconf->port = 0;

	if(parv[0][0] == 'K')
		aconf->user = rb_strdup(parv[para++]);

	aconf->host = rb_strdup(parv[para++]);
	aconf->info.oper = operhash_add(parv[para++]);

	switch (parv[0][0])
	{
	case 'K':
		aconf->status = CONF_KILL;
		break;

	case 'D':
		aconf->status = CONF_DLINE;
		break;

	case 'X':
		aconf->status = CONF_XLINE;
		break;

	case 'R':
		if(IsChannelName(aconf->host))
			aconf->status = CONF_RESV_CHANNEL;
		else
			aconf->status = CONF_RESV_NICK;

		break;
	}

	if((p = strchr(parv[para], '|')))
	{
		*p++ = '\0';
		aconf->spasswd = rb_strdup(p);
	}

	aconf->passwd = rb_strdup(parv[para]);

	rb_dlinkAddAlloc(aconf, &bandb_pending);
}

static int
bandb_check_kline(struct ConfItem *aconf)
{
	struct rb_sockaddr_storage daddr;
	struct ConfItem *kconf = NULL;
	int aftype;
	const char *p;

	aftype = parse_netmask(aconf->host, &daddr, NULL);

	if(aftype != HM_HOST)
	{
		if(aftype == HM_IPV6)
			aftype = AF_INET6;
		else
			aftype = AF_INET;

		kconf = find_conf_by_address(aconf->host, NULL, NULL, (struct sockaddr *)&daddr,
					     CONF_KILL, aftype, aconf->user, NULL);
	}
	else
		kconf = find_conf_by_address(aconf->host, NULL, NULL, NULL, CONF_KILL, 0, aconf->user, NULL);

	if(kconf && ((kconf->flags & CONF_FLAGS_TEMPORARY) == 0))
		return 0;

	for(p = aconf->user; *p; p++)
	{
		if(!IsUserChar(*p) && !IsKWildChar(*p))
			return 0;
	}

	for(p = aconf->host; *p; p++)
	{
		if(!IsHostChar(*p) && !IsKWildChar(*p))
			return 0;
	}

	return 1;
}

static int
bandb_check_dline(struct ConfItem *aconf)
{
	struct rb_sockaddr_storage daddr;
	int bits;

	if(!parse_netmask(aconf->host, &daddr, &bits))
		return 0;

	return 1;
}

static int
bandb_check_xline(struct ConfItem *aconf)
{
	struct ConfItem *xconf;
	/* XXX perhaps convert spaces to \s? -- jilles */

	xconf = find_xline_mask(aconf->host);
	if(xconf != NULL && !(xconf->flags & CONF_FLAGS_TEMPORARY))
		return 0;

	return 1;
}

static int
bandb_check_resv_channel(struct ConfItem *aconf)
{
	const char *p;

	if(hash_find_resv(aconf->host) || strlen(aconf->host) > CHANNELLEN)
		return 0;

	for(p = aconf->host; *p; p++)
	{
		if(!IsChanChar(*p))
			return 0;
	}

	return 1;
}

static int
bandb_check_resv_nick(struct ConfItem *aconf)
{
	if(!clean_resv_nick(aconf->host))
		return 0;

	if(find_nick_resv(aconf->host))
		return 0;

	return 1;
}

static void
bandb_handle_clear(void)
{
	rb_dlink_node *ptr, *next_ptr;

	RB_DLINK_FOREACH_SAFE(ptr, next_ptr, bandb_pending.head)
	{
		free_conf(ptr->data);
		rb_dlinkDestroy(ptr, &bandb_pending);
	}
}

static void
bandb_handle_finish(void)
{
	struct ConfItem *aconf;
	rb_dlink_node *ptr, *next_ptr;

	clear_out_address_conf(AC_BANDB);
	clear_s_newconf_bans();

	RB_DLINK_FOREACH_SAFE(ptr, next_ptr, bandb_pending.head)
	{
		aconf = ptr->data;

		rb_dlinkDestroy(ptr, &bandb_pending);

		switch (aconf->status)
		{
		case CONF_KILL:
			if(bandb_check_kline(aconf))
				add_conf_by_address(aconf->host, CONF_KILL, aconf->user, NULL, aconf);
			else
				free_conf(aconf);

			break;

		case CONF_DLINE:
			if(bandb_check_dline(aconf))
				add_conf_by_address(aconf->host, CONF_DLINE, aconf->user, NULL, aconf);
			else
				free_conf(aconf);

			break;

		case CONF_XLINE:
			if(bandb_check_xline(aconf))
				rb_dlinkAddAlloc(aconf, &xline_conf_list);
			else
				free_conf(aconf);

			break;

		case CONF_RESV_CHANNEL:
			if(bandb_check_resv_channel(aconf))
				add_to_resv_hash(aconf->host, aconf);
			else
				free_conf(aconf);

			break;

		case CONF_RESV_NICK:
			if(bandb_check_resv_nick(aconf))
				rb_dlinkAddAlloc(aconf, &resv_conf_list);
			else
				free_conf(aconf);

			break;
		}
	}

	check_banned_lines();
}

static void
bandb_handle_failure(rb_helper *helper, char **parv, int parc)
{
	if(server_state_foreground)
		fprintf(stderr, "bandb - bandb failure: %s\n", parv[1]);

	ilog(L_MAIN, "bandb - bandb failure: %s", parv[1]);
	sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "bandb - bandb failure: %s", parv[1]);
	exit(1);
}

static void
bandb_parse(rb_helper *helper)
{
	static char buf[READBUF_SIZE];
	char *parv[MAXPARA];
	int len, parc;

	while((len = rb_helper_read(helper, buf, sizeof(buf))))
	{
		parc = rb_string_to_array(buf, parv, sizeof(parv));

		if(parc < 1)
			continue;

		switch (parv[0][0])
		{
		case '!':
			bandb_handle_failure(helper, parv, parc);
			break;
		case 'K':
		case 'D':
		case 'X':
		case 'R':
			bandb_handle_ban(parv, parc);
			break;

		case 'C':
			bandb_handle_clear();
			break;
		case 'F':
			bandb_handle_finish();
			break;
		}
	}
}

void
bandb_rehash_bans(void)
{
	if(bandb_helper != NULL)
		rb_helper_write(bandb_helper, "L");
}

static void
bandb_restart_cb(rb_helper *helper)
{
	ilog(L_MAIN, "bandb helper died - attempting to restart");
	sendto_realops_snomask(SNO_GENERAL, L_NETWIDE,
			     "bandb helper died - attempting to restart");
	if(helper != NULL)
	{
		rb_helper_close(helper);
		bandb_helper = NULL;
	}
	start_bandb();
	return;
}
