/*
 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, you can obtain one at https://mozilla.org/MPL/2.0/.
 *
 * See the COPYRIGHT file distributed with this work for additional
 * information regarding copyright ownership.
 */

#ifndef ISC_NET_H
#define ISC_NET_H 1

/*****
***** Module Info
*****/

/*! \file
 * \brief
 * Basic Networking Types
 *
 * This module is responsible for defining the following basic networking
 * types:
 *
 *\li		struct in_addr
 *\li		struct in6_addr
 *\li		struct in6_pktinfo
 *\li		struct sockaddr
 *\li		struct sockaddr_in
 *\li		struct sockaddr_in6
 *\li		struct sockaddr_storage
 *\li		in_port_t
 *
 * It ensures that the AF_ and PF_ macros are defined.
 *
 * It declares ntoh[sl]() and hton[sl]().
 *
 * It declares inet_ntop(), and inet_pton().
 *
 * It ensures that #INADDR_LOOPBACK, #INADDR_ANY, #IN6ADDR_ANY_INIT,
 * IN6ADDR_V4MAPPED_INIT, in6addr_any, and in6addr_loopback are available.
 *
 * It ensures that IN_MULTICAST() is available to check for multicast
 * addresses.
 *
 * MP:
 *\li	No impact.
 *
 * Reliability:
 *\li	No anticipated impact.
 *
 * Resources:
 *\li	N/A.
 *
 * Security:
 *\li	No anticipated impact.
 *
 * Standards:
 *\li	BSD Socket API
 *\li	RFC2553
 */

/***
 *** Imports.
 ***/
#include <inttypes.h>

#include <isc/lang.h>
#include <isc/platform.h>
#include <isc/types.h>

#include <arpa/inet.h> /* Contractual promise. */
#include <net/if.h>
#include <netinet/in.h> /* Contractual promise. */
#include <sys/socket.h> /* Contractual promise. */
#include <sys/types.h>

#ifndef IN6ADDR_LOOPBACK_INIT
#ifdef s6_addr
/*% IPv6 address loopback init */
#define IN6ADDR_LOOPBACK_INIT                                                  \
	{                                                                      \
		{                                                              \
			{                                                      \
				0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 \
			}                                                      \
		}                                                              \
	}
#else /* ifdef s6_addr */
#define IN6ADDR_LOOPBACK_INIT                                          \
	{                                                              \
		{                                                      \
			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 \
		}                                                      \
	}
#endif /* ifdef s6_addr */
#endif /* ifndef IN6ADDR_LOOPBACK_INIT */

#ifndef IN6ADDR_V4MAPPED_INIT
#ifdef s6_addr
/*% IPv6 v4mapped prefix init */
#define IN6ADDR_V4MAPPED_INIT                                                \
	{                                                                    \
		{                                                            \
			{                                                    \
				0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 0, \
					0, 0, 0                              \
			}                                                    \
		}                                                            \
	}
#else /* ifdef s6_addr */
#define IN6ADDR_V4MAPPED_INIT                                                \
	{                                                                    \
		{                                                            \
			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff, 0, 0, 0, 0 \
		}                                                            \
	}
#endif /* ifdef s6_addr */
#endif /* ifndef IN6ADDR_V4MAPPED_INIT */

#ifndef IN6_IS_ADDR_V4MAPPED
/*% Is IPv6 address V4 mapped? */
#define IN6_IS_ADDR_V4MAPPED(x)                                \
	(memcmp((x)->s6_addr, in6addr_any.s6_addr, 10) == 0 && \
	 (x)->s6_addr[10] == 0xff && (x)->s6_addr[11] == 0xff)
#endif /* ifndef IN6_IS_ADDR_V4MAPPED */

#ifndef IN6_IS_ADDR_V4COMPAT
/*% Is IPv6 address V4 compatible? */
#define IN6_IS_ADDR_V4COMPAT(x)                                \
	(memcmp((x)->s6_addr, in6addr_any.s6_addr, 12) == 0 && \
	 ((x)->s6_addr[12] != 0 || (x)->s6_addr[13] != 0 ||    \
	  (x)->s6_addr[14] != 0 ||                             \
	  ((x)->s6_addr[15] != 0 && (x)->s6_addr[15] != 1)))
#endif /* ifndef IN6_IS_ADDR_V4COMPAT */

#ifndef IN6_IS_ADDR_MULTICAST
/*% Is IPv6 address multicast? */
#define IN6_IS_ADDR_MULTICAST(a) ((a)->s6_addr[0] == 0xff)
#endif /* ifndef IN6_IS_ADDR_MULTICAST */

#ifndef IN6_IS_ADDR_LINKLOCAL
/*% Is IPv6 address linklocal? */
#define IN6_IS_ADDR_LINKLOCAL(a) \
	(((a)->s6_addr[0] == 0xfe) && (((a)->s6_addr[1] & 0xc0) == 0x80))
#endif /* ifndef IN6_IS_ADDR_LINKLOCAL */

#ifndef IN6_IS_ADDR_SITELOCAL
/*% is IPv6 address sitelocal? */
#define IN6_IS_ADDR_SITELOCAL(a) \
	(((a)->s6_addr[0] == 0xfe) && (((a)->s6_addr[1] & 0xc0) == 0xc0))
#endif /* ifndef IN6_IS_ADDR_SITELOCAL */

#ifndef IN6_IS_ADDR_LOOPBACK
/*% is IPv6 address loopback? */
#define IN6_IS_ADDR_LOOPBACK(x) \
	(memcmp((x)->s6_addr, in6addr_loopback.s6_addr, 16) == 0)
#endif /* ifndef IN6_IS_ADDR_LOOPBACK */

#ifndef AF_INET6
/*% IPv6 */
#define AF_INET6 99
#endif /* ifndef AF_INET6 */

#ifndef PF_INET6
/*% IPv6 */
#define PF_INET6 AF_INET6
#endif /* ifndef PF_INET6 */

#ifndef INADDR_ANY
/*% inaddr any */
#define INADDR_ANY 0x00000000UL
#endif /* ifndef INADDR_ANY */

#ifndef INADDR_LOOPBACK
/*% inaddr loopback */
#define INADDR_LOOPBACK 0x7f000001UL
#endif /* ifndef INADDR_LOOPBACK */

#ifndef MSG_TRUNC
/*%
 * If this system does not have MSG_TRUNC (as returned from recvmsg())
 * ISC_PLATFORM_RECVOVERFLOW will be defined.  This will enable the MSG_TRUNC
 * faking code in socket.c.
 */
#define ISC_PLATFORM_RECVOVERFLOW
#endif /* ifndef MSG_TRUNC */

/*% IP address. */
#define ISC__IPADDR(x) ((uint32_t)htonl((uint32_t)(x)))

/*% Is IP address multicast? */
#define ISC_IPADDR_ISMULTICAST(i) \
	(((uint32_t)(i)&ISC__IPADDR(0xf0000000)) == ISC__IPADDR(0xe0000000))

#define ISC_IPADDR_ISEXPERIMENTAL(i) \
	(((uint32_t)(i)&ISC__IPADDR(0xf0000000)) == ISC__IPADDR(0xf0000000))

/***
 *** Functions.
 ***/

ISC_LANG_BEGINDECLS

isc_result_t
isc_net_probeipv4(void);
/*%<
 * Check if the system's kernel supports IPv4.
 *
 * Returns:
 *
 *\li	#ISC_R_SUCCESS		IPv4 is supported.
 *\li	#ISC_R_NOTFOUND		IPv4 is not supported.
 *\li	#ISC_R_DISABLED		IPv4 is disabled.
 *\li	#ISC_R_UNEXPECTED
 */

isc_result_t
isc_net_probeipv6(void);
/*%<
 * Check if the system's kernel supports IPv6.
 *
 * Returns:
 *
 *\li	#ISC_R_SUCCESS		IPv6 is supported.
 *\li	#ISC_R_NOTFOUND		IPv6 is not supported.
 *\li	#ISC_R_DISABLED		IPv6 is disabled.
 *\li	#ISC_R_UNEXPECTED
 */

isc_result_t
isc_net_probe_ipv6only(void);
/*%<
 * Check if the system's kernel supports the IPV6_V6ONLY socket option.
 *
 * Returns:
 *
 *\li	#ISC_R_SUCCESS		the option is supported for both TCP and UDP.
 *\li	#ISC_R_NOTFOUND		IPv6 itself or the option is not supported.
 *\li	#ISC_R_UNEXPECTED
 */

isc_result_t
isc_net_probe_ipv6pktinfo(void);
/*
 * Check if the system's kernel supports the IPV6_(RECV)PKTINFO socket option
 * for UDP sockets.
 *
 * Returns:
 *
 * \li	#ISC_R_SUCCESS		the option is supported.
 * \li	#ISC_R_NOTFOUND		IPv6 itself or the option is not supported.
 * \li	#ISC_R_UNEXPECTED
 */

void
isc_net_disableipv4(void);

void
isc_net_disableipv6(void);

void
isc_net_enableipv4(void);

void
isc_net_enableipv6(void);

isc_result_t
isc_net_probeunix(void);
/*
 * Returns whether UNIX domain sockets are supported.
 */

#define ISC_NET_DSCPRECVV4 0x01 /* Can receive sent DSCP value IPv4 */
#define ISC_NET_DSCPRECVV6 0x02 /* Can receive sent DSCP value IPv6 */
#define ISC_NET_DSCPSETV4  0x04 /* Can set DSCP on socket IPv4 */
#define ISC_NET_DSCPSETV6  0x08 /* Can set DSCP on socket IPv6 */
#define ISC_NET_DSCPPKTV4  0x10 /* Can set DSCP on per packet IPv4 */
#define ISC_NET_DSCPPKTV6  0x20 /* Can set DSCP on per packet IPv6 */
#define ISC_NET_DSCPALL	   0x3f /* All valid flags */

unsigned int
isc_net_probedscp(void);
/*%<
 * Probe the level of DSCP support.
 */

isc_result_t
isc_net_getudpportrange(int af, in_port_t *low, in_port_t *high);
/*%<
 * Returns system's default range of ephemeral UDP ports, if defined.
 * If the range is not available or unknown, ISC_NET_PORTRANGELOW and
 * ISC_NET_PORTRANGEHIGH will be returned.
 *
 * Requires:
 *
 *\li	'low' and 'high' must be non NULL.
 *
 * Returns:
 *
 *\li	*low and *high will be the ports specifying the low and high ends of
 *	the range.
 */

ISC_LANG_ENDDECLS

#endif /* ISC_NET_H */
