#include <stdio.h>

#include <xtables.h>

#include <linux/netfilter/xt_esp.h>

enum {

	O_ESPSPI = 0,

};

static void esp_help(void)

{

	printf(

"esp match options:\n"

"[!] --espspi spi[:spi]\n"

"				match spi (range)\n");

}

static const struct xt_option_entry esp_opts[] = {

	{.name = "espspi", .id = O_ESPSPI, .type = XTTYPE_UINT32RC,

	 .flags = XTOPT_INVERT | XTOPT_PUT,

	 XTOPT_POINTER(struct xt_esp, spis)},

	XTOPT_TABLEEND,

};

static void esp_init(struct xt_entry_match *m)

{

	struct xt_esp *espinfo = (void *)m->data;

	espinfo->spis[1] = ~0U;

}

static void esp_parse(struct xt_option_call *cb)

{

	struct xt_esp *espinfo = cb->data;

	xtables_option_parse(cb);

	if (cb->nvals == 1)

		espinfo->spis[1] = espinfo->spis[0];

	if (cb->invert)

		espinfo->invflags |= XT_ESP_INV_SPI;

}

static void

print_spis(const char *name, uint32_t min, uint32_t max,

	    int invert)

{

	const char *inv = invert ? "!" : "";

	if (min != 0 || max != 0xFFFFFFFF || invert) {

		if (min == max)

			printf(" %s:%s%u", name, inv, min);

		else

			printf(" %ss:%s%u:%u", name, inv, min, max);

	}

}

static void

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

{

	const struct xt_esp *esp = (struct xt_esp *)match->data;

	printf(" esp");

	print_spis("spi", esp->spis[0], esp->spis[1],

		    esp->invflags & XT_ESP_INV_SPI);

	if (esp->invflags & ~XT_ESP_INV_MASK)

		printf(" Unknown invflags: 0x%X",

		       esp->invflags & ~XT_ESP_INV_MASK);

}

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

{

	const struct xt_esp *espinfo = (struct xt_esp *)match->data;

	if (!(espinfo->spis[0] == 0

	    && espinfo->spis[1] == 0xFFFFFFFF)) {

		printf("%s --espspi ",

			(espinfo->invflags & XT_ESP_INV_SPI) ? " !" : "");

		if (espinfo->spis[0]

		    != espinfo->spis[1])

			printf("%u:%u",

			       espinfo->spis[0],

			       espinfo->spis[1]);

		else

			printf("%u",

			       espinfo->spis[0]);

	}

}

static int esp_xlate(struct xt_xlate *xl,

		     const struct xt_xlate_mt_params *params)

{

	const struct xt_esp *espinfo = (struct xt_esp *)params->match->data;

	if (!(espinfo->spis[0] == 0 && espinfo->spis[1] == 0xFFFFFFFF)) {

		xt_xlate_add(xl, "esp spi%s",

			   (espinfo->invflags & XT_ESP_INV_SPI) ? " !=" : "");

		if (espinfo->spis[0] != espinfo->spis[1])

			xt_xlate_add(xl, " %u-%u", espinfo->spis[0],

				   espinfo->spis[1]);

		else

			xt_xlate_add(xl, " %u", espinfo->spis[0]);

	}

	return 1;

}

static struct xtables_match esp_match = {

	.family		= NFPROTO_UNSPEC,

	.name		= "esp",

	.version	= XTABLES_VERSION,

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

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

	.help		= esp_help,

	.init		= esp_init,

	.print		= esp_print,

	.save		= esp_save,

	.x6_parse	= esp_parse,

	.x6_options	= esp_opts,

	.xlate		= esp_xlate,

};

void

_init(void)

{

	xtables_register_match(&esp_match);

}