/**
 * Copyright (C) 2012-2014 Steven Barth <steven@midlink.org>
 * Copyright (C) 2018 Hans Dedecker <dedeckeh@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License v2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#ifndef _RA_H_
#define _RA_H_

#include <netinet/in.h>
#include <stdbool.h>
#include <stdint.h>

#define ALL_IPV6_NODES {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}}}

#define ALL_IPV6_ROUTERS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
		0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02}}}

struct icmpv6_opt {
	uint8_t type;
	uint8_t len;
	uint8_t data[6];
};

/* RFC8910 Captive-Portal §2.3 */
struct icmpv6_opt_captive_portal {
	uint8_t type; /* 37 */
	uint8_t len; /* includes the Type and Length fields, in units of 8 bytes */
	uint8_t data[]; /* padded with NUL (0x00) to make length multiple of 8 */
};

struct icmpv6_opt_route_info {
	uint8_t type;
	uint8_t len;
	uint8_t prefix_len;
	uint8_t flags;
	uint32_t lifetime;
	uint8_t prefix[];
};

typedef enum ra_ifid_mode {
	RA_IFID_EUI64,
	RA_IFID_FIXED,
	RA_IFID_RANDOM,
	RA_IFID_LLA,
} ra_ifid_mode_t;

#define ND_OPT_ROUTE_INFORMATION 24
#define ND_OPT_CAPTIVE_PORTAL 37


#define icmpv6_for_each_option(opt, start, end)\
	for (opt = (struct icmpv6_opt*)(start);\
	(void*)(opt + 1) <= (void*)(end) && opt->len > 0 &&\
	(void*)(opt + opt->len) <= (void*)(end); opt += opt->len)


int ra_init(const char *ifname, const struct in6_addr *ifid,
	    ra_ifid_mode_t ifid_mode, unsigned int options,
	    unsigned int holdoff_interval);
bool ra_link_up(void);
bool ra_process(void);

#endif /* _RA_H_ */