/*

 * (C) 2009 by Pablo Neira Ayuso <pablo@netfilter.org>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

#include <stdio.h>

#include <xtables.h>

#include <linux/netfilter/xt_cluster.h>

static void

cluster_help(void)

{

	printf(

"cluster match options:\n"

"  --cluster-total-nodes <num>		Set number of total nodes in cluster\n"

"  [!] --cluster-local-node <num>	Set the local node number\n"

"  [!] --cluster-local-nodemask <num>	Set the local node mask\n"

"  --cluster-hash-seed <num>		Set seed value of the Jenkins hash\n");

}

enum {

	O_CL_TOTAL_NODES = 0,

	O_CL_LOCAL_NODE,

	O_CL_LOCAL_NODEMASK,

	O_CL_HASH_SEED,

	F_CL_TOTAL_NODES    = 1 << O_CL_TOTAL_NODES,

	F_CL_LOCAL_NODE     = 1 << O_CL_LOCAL_NODE,

	F_CL_LOCAL_NODEMASK = 1 << O_CL_LOCAL_NODEMASK,

	F_CL_HASH_SEED      = 1 << O_CL_HASH_SEED,

};

#define s struct xt_cluster_match_info

static const struct xt_option_entry cluster_opts[] = {

	{.name = "cluster-total-nodes", .id = O_CL_TOTAL_NODES,

	 .type = XTTYPE_UINT32, .min = 1, .max = XT_CLUSTER_NODES_MAX,

	 .flags = XTOPT_MAND | XTOPT_PUT, XTOPT_POINTER(s, total_nodes)},

	{.name = "cluster-local-node", .id = O_CL_LOCAL_NODE,

	 .excl = F_CL_LOCAL_NODEMASK, .flags = XTOPT_INVERT,

	 .type = XTTYPE_UINT32, .min = 1, .max = XT_CLUSTER_NODES_MAX},

	{.name = "cluster-local-nodemask", .id = O_CL_LOCAL_NODEMASK,

	 .excl = F_CL_LOCAL_NODE, .type = XTTYPE_UINT32,

	 .min = 1, .max = XT_CLUSTER_NODES_MAX,

	 .flags = XTOPT_INVERT | XTOPT_PUT, XTOPT_POINTER(s, node_mask)},

	{.name = "cluster-hash-seed", .id = O_CL_HASH_SEED,

	 .type = XTTYPE_UINT32, .flags = XTOPT_MAND | XTOPT_PUT,

	 XTOPT_POINTER(s, hash_seed)},

	XTOPT_TABLEEND,

};

static void cluster_parse(struct xt_option_call *cb)

{

	struct xt_cluster_match_info *info = cb->data;

	xtables_option_parse(cb);

	switch (cb->entry->id) {

	case O_CL_LOCAL_NODE:

		if (cb->invert)

			info->flags |= XT_CLUSTER_F_INV;

		info->node_mask = 1 << (cb->val.u32 - 1);

		break;

	case O_CL_LOCAL_NODEMASK:

		if (cb->invert)

			info->flags |= XT_CLUSTER_F_INV;

		break;

	}

}

static void cluster_check(struct xt_fcheck_call *cb)

{

	const struct xt_cluster_match_info *info = cb->data;

	unsigned int test;

	test = F_CL_TOTAL_NODES | F_CL_LOCAL_NODE | F_CL_HASH_SEED;

	if ((cb->xflags & test) == test) {

		if (info->node_mask >= (1ULL << info->total_nodes))

			xtables_error(PARAMETER_PROBLEM,

				      "cluster match: "

				      "`--cluster-local-node' "

				      "must be <= `--cluster-total-nodes'");

		return;

	}

	test = F_CL_TOTAL_NODES | F_CL_LOCAL_NODEMASK | F_CL_HASH_SEED;

	if ((cb->xflags & test) == test) {

		if (info->node_mask >= (1ULL << info->total_nodes))

			xtables_error(PARAMETER_PROBLEM,

				      "cluster match: "

				      "`--cluster-local-nodemask' too big "

				      "for `--cluster-total-nodes'");

		return;

	}

	if (!(cb->xflags & (F_CL_LOCAL_NODE | F_CL_LOCAL_NODEMASK)))

		xtables_error(PARAMETER_PROBLEM,

			      "cluster match: `--cluster-local-node' or"

			      "`--cluster-local-nodemask' is missing");

}

static void

cluster_print(const void *ip, const struct xt_entry_match *match, int numeric)

{

	const struct xt_cluster_match_info *info = (void *)match->data;

	printf(" cluster ");

	if (info->flags & XT_CLUSTER_F_INV)

		printf("!node_mask=0x%08x", info->node_mask);

	else

		printf("node_mask=0x%08x", info->node_mask);

	printf(" total_nodes=%u hash_seed=0x%08x",

		info->total_nodes, info->hash_seed);

}

static void

cluster_save(const void *ip, const struct xt_entry_match *match)

{

	const struct xt_cluster_match_info *info = (void *)match->data;

	if (info->flags & XT_CLUSTER_F_INV)

		printf(" ! --cluster-local-nodemask 0x%08x", info->node_mask);

	else

		printf(" --cluster-local-nodemask 0x%08x", info->node_mask);

	printf(" --cluster-total-nodes %u --cluster-hash-seed 0x%08x",

		info->total_nodes, info->hash_seed);

}

static int cluster_xlate(struct xt_xlate *xl,

			 const struct xt_xlate_mt_params *params)

{

	int node, shift_value = 1, comma_needed = 0;

	uint32_t temp_node_mask, node_id = 0, needs_set = 0;

	const struct xt_cluster_match_info *info = (void *)params->match->data;

	const char *jhash_st = "jhash ct original saddr mod";

	const char *pkttype_st = "meta pkttype set host";

	if (!(info->node_mask & (info->node_mask - 1))) {

		if (info->node_mask <= 2)

			xt_xlate_add(xl, "%s %u seed 0x%08x eq %u %s", jhash_st,

					info->total_nodes, info->hash_seed,

					info->node_mask, pkttype_st);

		else {

			temp_node_mask = info->node_mask;

			while (1) {

				temp_node_mask = temp_node_mask >> shift_value;

				node_id++;

				if (temp_node_mask == 0)

					break;

			}

			xt_xlate_add(xl, "%s %u seed 0x%08x eq %u %s", jhash_st,

					info->total_nodes, info->hash_seed,

					node_id, pkttype_st);

		}

	} else {

		xt_xlate_add(xl, "%s %u seed 0x%08x ", jhash_st,

				info->total_nodes, info->hash_seed);

		for (node = 0; node < 32; node++) {

			if (info->node_mask & (1 << node)) {

				if (needs_set == 0) {

					xt_xlate_add(xl, "{ ");

					needs_set = 1;

				}

				if (comma_needed)

					xt_xlate_add(xl, ", ");

				xt_xlate_add(xl, "%u", node);

				comma_needed++;

			}

		}

		if (needs_set)

			xt_xlate_add(xl, " }");

		xt_xlate_add(xl, " %s", pkttype_st);

	}

	return 1;

}

static struct xtables_match cluster_mt_reg = {

	.family		= NFPROTO_UNSPEC,

	.name		= "cluster",

	.version	= XTABLES_VERSION,

	.size		= XT_ALIGN(sizeof(struct xt_cluster_match_info)),

	.userspacesize  = XT_ALIGN(sizeof(struct xt_cluster_match_info)),

 	.help		= cluster_help,

	.print		= cluster_print,

	.save		= cluster_save,

	.x6_parse	= cluster_parse,

	.x6_fcheck	= cluster_check,

	.x6_options	= cluster_opts,

	.xlate		= cluster_xlate,

};

void _init(void)

{

	xtables_register_match(&cluster_mt_reg);

}