#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <errno.h>

#if defined(__GLIBC__) && __GLIBC__ == 2

#include <net/ethernet.h>

#else

#include <linux/if_ether.h>

#endif

#include <xtables.h>

#include <linux/netfilter_ipv4/ipt_realm.h>

enum {

	O_REALM = 0,

};

static void realm_help(void)

{

	printf(

"realm match options:\n"

"[!] --realm value[/mask]\n"

"				Match realm\n");

}

static const struct xt_option_entry realm_opts[] = {

	{.name = "realm", .id = O_REALM, .type = XTTYPE_STRING,

	 .flags = XTOPT_MAND | XTOPT_INVERT},

	XTOPT_TABLEEND,

};

static const char f_realms[] = "/etc/iproute2/rt_realms";

/* array of realms from f_realms[] */

static struct xtables_lmap *realms;

static void realm_parse(struct xt_option_call *cb)

{

	struct xt_realm_info *ri = cb->data;

	unsigned int id, mask;

	xtables_option_parse(cb);

	xtables_parse_val_mask(cb, &id, &mask, realms);

	ri->id = id;

	ri->mask = mask;

	if (cb->invert)

		ri->invert = 1;

}

static void realm_print(const void *ip, const struct xt_entry_match *match,

			int numeric)

{

	const struct xt_realm_info *ri = (const void *)match->data;

	if (ri->invert)

		printf(" !");

	printf(" realm");

	xtables_print_val_mask(ri->id, ri->mask, numeric ? NULL : realms);

}

static void realm_save(const void *ip, const struct xt_entry_match *match)

{

	const struct xt_realm_info *ri = (const void *)match->data;

	if (ri->invert)

		printf(" !");

	printf(" --realm");

	xtables_print_val_mask(ri->id, ri->mask, realms);

}

static void

print_realm_xlate(unsigned long id, unsigned long mask,

		  int numeric, struct xt_xlate *xl, uint32_t op)

{

	const char *name = NULL;

	if (mask != 0xffffffff)

		xt_xlate_add(xl, " and 0x%lx %s 0x%lx", mask,

			   op == XT_OP_EQ ? "==" : "!=", id);

	else {

		if (numeric == 0)

			name = xtables_lmap_id2name(realms, id);

		if (name)

			xt_xlate_add(xl, " %s%s",

				   op == XT_OP_EQ ? "" : "!= ", name);

		else

			xt_xlate_add(xl, " %s0x%lx",

				   op == XT_OP_EQ ? "" : "!= ", id);

	}

}

static int realm_xlate(struct xt_xlate *xl,

		       const struct xt_xlate_mt_params *params)

{

	const struct xt_realm_info *ri = (const void *)params->match->data;

	enum xt_op op = XT_OP_EQ;

	if (ri->invert)

		op = XT_OP_NEQ;

	xt_xlate_add(xl, "rtclassid");

	print_realm_xlate(ri->id, ri->mask, 0, xl, op);

	return 1;

}

static struct xtables_match realm_mt_reg = {

	.name		= "realm",

	.version	= XTABLES_VERSION,

	.family		= NFPROTO_IPV4,

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

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

	.help		= realm_help,

	.print		= realm_print,

	.save		= realm_save,

	.x6_parse	= realm_parse,

	.x6_options	= realm_opts,

	.xlate		= realm_xlate,

};

void _init(void)

{

	realms = xtables_lmap_init(f_realms);

	if (realms == NULL && errno != ENOENT)

		fprintf(stderr, "Warning: %s: %s\n", f_realms,

			strerror(errno));

	xtables_register_match(&realm_mt_reg);

}