/*      $NetBSD: in.h,v 1.115 2023/06/16 03:02:30 rin Exp $     */

/*
 * Copyright (c) 1982, 1986, 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)in.h        8.3 (Berkeley) 1/3/94
 */

/*
 * Constants and structures defined by the internet system,
 * Per RFC 790, September 1981, and numerous additions.
 */

#ifndef _NETINET_IN_H_
#define _NETINET_IN_H_

#include <sys/featuretest.h>
#include <machine/int_types.h>

#ifndef _BSD_UINT8_T_
typedef __uint8_t       uint8_t;
#define _BSD_UINT8_T_
#endif

#ifndef _BSD_UINT32_T_
typedef __uint32_t      uint32_t;
#define _BSD_UINT32_T_
#endif

#include <sys/ansi.h>

#ifndef in_addr_t
typedef __in_addr_t     in_addr_t;
#define in_addr_t       __in_addr_t
#endif

#ifndef in_port_t
typedef __in_port_t     in_port_t;
#define in_port_t       __in_port_t
#endif

#ifndef sa_family_t
typedef __sa_family_t   sa_family_t;
#define sa_family_t     __sa_family_t
#endif

/*
 * Protocols
 */
#define IPPROTO_IP              0               /* dummy for IP */
#define IPPROTO_HOPOPTS         0               /* IP6 hop-by-hop options */
#define IPPROTO_ICMP            1               /* control message protocol */
#define IPPROTO_IGMP            2               /* group mgmt protocol */
#define IPPROTO_GGP             3               /* gateway^2 (deprecated) */
#define IPPROTO_IPV4            4               /* IP header */
#define IPPROTO_IPIP            4               /* IP inside IP */
#define IPPROTO_TCP             6               /* tcp */
#define IPPROTO_EGP             8               /* exterior gateway protocol */
#define IPPROTO_PUP             12              /* pup */
#define IPPROTO_UDP             17              /* user datagram protocol */
#define IPPROTO_IDP             22              /* xns idp */
#define IPPROTO_TP              29              /* tp-4 w/ class negotiation */
#define IPPROTO_DCCP            33              /* DCCP */
#define IPPROTO_IPV6            41              /* IP6 header */
#define IPPROTO_ROUTING         43              /* IP6 routing header */
#define IPPROTO_FRAGMENT        44              /* IP6 fragmentation header */
#define IPPROTO_RSVP            46              /* resource reservation */
#define IPPROTO_GRE             47              /* GRE encaps RFC 1701 */
#define IPPROTO_ESP             50              /* encap. security payload */
#define IPPROTO_AH              51              /* authentication header */
#define IPPROTO_MOBILE          55              /* IP Mobility RFC 2004 */
#define IPPROTO_IPV6_ICMP       58              /* IPv6 ICMP */
#define IPPROTO_ICMPV6          58              /* ICMP6 */
#define IPPROTO_NONE            59              /* IP6 no next header */
#define IPPROTO_DSTOPTS         60              /* IP6 destination option */
#define IPPROTO_EON             80              /* ISO cnlp */
#define IPPROTO_ETHERIP         97              /* Ethernet-in-IP */
#define IPPROTO_ENCAP           98              /* encapsulation header */
#define IPPROTO_PIM             103             /* Protocol indep. multicast */
#define IPPROTO_IPCOMP          108             /* IP Payload Comp. Protocol */
#define IPPROTO_VRRP            112             /* VRRP RFC 2338 */
#define IPPROTO_CARP            112             /* Common Address Resolution Protocol */
#define IPPROTO_L2TP            115             /* L2TPv3 */
#define IPPROTO_SCTP            132             /* SCTP */
#define IPPROTO_PFSYNC          240             /* PFSYNC */
#define IPPROTO_RAW             255             /* raw IP packet */
#define IPPROTO_MAX             256

/* last return value of *_input(), meaning "all job for this pkt is done".  */
#define IPPROTO_DONE            257

/* sysctl placeholder for (FAST_)IPSEC */
#define CTL_IPPROTO_IPSEC       258


/*
 * Local port number conventions:
 *
 * Ports < IPPORT_RESERVED are reserved for privileged processes (e.g. root),
 * unless a kernel is compiled with IPNOPRIVPORTS defined.
 *
 * When a user does a bind(2) or connect(2) with a port number of zero,
 * a non-conflicting local port address is chosen.
 *
 * The default range is IPPORT_ANONMIN to IPPORT_ANONMAX, although
 * that is settable by sysctl(3); net.inet.ip.anonportmin and
 * net.inet.ip.anonportmax respectively.
 *
 * A user may set the IPPROTO_IP option IP_PORTRANGE to change this
 * default assignment range.
 *
 * The value IP_PORTRANGE_DEFAULT causes the default behavior.
 *
 * The value IP_PORTRANGE_HIGH is the same as IP_PORTRANGE_DEFAULT,
 * and exists only for FreeBSD compatibility purposes.
 *
 * The value IP_PORTRANGE_LOW changes the range to the "low" are
 * that is (by convention) restricted to privileged processes.
 * This convention is based on "vouchsafe" principles only.
 * It is only secure if you trust the remote host to restrict these ports.
 * The range is IPPORT_RESERVEDMIN to IPPORT_RESERVEDMAX.
 */

#define IPPORT_RESERVED         1024
#define IPPORT_ANONMIN          49152
#define IPPORT_ANONMAX          65535
#define IPPORT_RESERVEDMIN      600
#define IPPORT_RESERVEDMAX      (IPPORT_RESERVED-1)

/*
 * Internet address (a structure for historical reasons)
 */
struct in_addr {
        in_addr_t s_addr;
};
#ifdef __CTASSERT
__CTASSERT(sizeof(struct in_addr) == 4);
#endif

/*
 * Definitions of bits in internet address integers.
 * On subnets, the decomposition of addresses to host and net parts
 * is done according to subnet mask, not the masks here.
 *
 * By byte-swapping the constants, we avoid ever having to byte-swap IP
 * addresses inside the kernel.  Unfortunately, user-level programs rely
 * on these macros not doing byte-swapping.
 */
#ifdef _KERNEL
#define __IPADDR(x)     ((uint32_t) htonl((uint32_t)(x)))
#else
#define __IPADDR(x)     ((uint32_t)(x))
#endif

#define IN_CLASSA(i)            (((uint32_t)(i) & __IPADDR(0x80000000)) == \
                                 __IPADDR(0x00000000))
#define IN_CLASSA_NET           __IPADDR(0xff000000)
#define IN_CLASSA_NSHIFT        24
#define IN_CLASSA_HOST          __IPADDR(0x00ffffff)
#define IN_CLASSA_MAX           128

#define IN_CLASSB(i)            (((uint32_t)(i) & __IPADDR(0xc0000000)) == \
                                 __IPADDR(0x80000000))
#define IN_CLASSB_NET           __IPADDR(0xffff0000)
#define IN_CLASSB_NSHIFT        16
#define IN_CLASSB_HOST          __IPADDR(0x0000ffff)
#define IN_CLASSB_MAX           65536

#define IN_CLASSC(i)            (((uint32_t)(i) & __IPADDR(0xe0000000)) == \
                                 __IPADDR(0xc0000000))
#define IN_CLASSC_NET           __IPADDR(0xffffff00)
#define IN_CLASSC_NSHIFT        8
#define IN_CLASSC_HOST          __IPADDR(0x000000ff)

#define IN_CLASSD(i)            (((uint32_t)(i) & __IPADDR(0xf0000000)) == \
                                 __IPADDR(0xe0000000))
/* These ones aren't really net and host fields, but routing needn't know. */
#define IN_CLASSD_NET           __IPADDR(0xf0000000)
#define IN_CLASSD_NSHIFT        28
#define IN_CLASSD_HOST          __IPADDR(0x0fffffff)
#define IN_MULTICAST(i)         IN_CLASSD(i)

#define IN_EXPERIMENTAL(i)      (((uint32_t)(i) & __IPADDR(0xf0000000)) == \
                                 __IPADDR(0xf0000000))
#define IN_BADCLASS(i)          (((uint32_t)(i) & __IPADDR(0xf0000000)) == \
                                 __IPADDR(0xf0000000))

#define IN_LINKLOCAL(i) (((uint32_t)(i) & __IPADDR(0xffff0000)) == \
                         __IPADDR(0xa9fe0000))

#define IN_PRIVATE(i)   ((((uint32_t)(i) & __IPADDR(0xff000000)) ==     \
                          __IPADDR(0x0a000000)) ||                      \
                         (((uint32_t)(i) & __IPADDR(0xfff00000)) ==     \
                          __IPADDR(0xac100000)) ||                      \
                         (((uint32_t)(i) & __IPADDR(0xffff0000)) ==     \
                          __IPADDR(0xc0a80000)))

#define IN_LOCAL_GROUP(i)       (((uint32_t)(i) & __IPADDR(0xffffff00)) == \
                                 __IPADDR(0xe0000000))

#define IN_ANY_LOCAL(i)         (IN_LINKLOCAL(i) || IN_LOCAL_GROUP(i))

#define INADDR_ANY              __IPADDR(0x00000000)
#define INADDR_LOOPBACK         __IPADDR(0x7f000001)
#define INADDR_BROADCAST        __IPADDR(0xffffffff)    /* must be masked */
#define INADDR_NONE             __IPADDR(0xffffffff)    /* -1 return */

#define INADDR_UNSPEC_GROUP     __IPADDR(0xe0000000)    /* 224.0.0.0 */
#define INADDR_ALLHOSTS_GROUP   __IPADDR(0xe0000001)    /* 224.0.0.1 */
#define INADDR_ALLRTRS_GROUP    __IPADDR(0xe0000002)    /* 224.0.0.2 */
#define INADDR_CARP_GROUP       __IPADDR(0xe0000012)    /* 224.0.0.18 */
#define INADDR_MAX_LOCAL_GROUP  __IPADDR(0xe00000ff)    /* 224.0.0.255 */

#define IN_LOOPBACKNET          127                     /* official! */

#define IN_RFC3021_MASK         __IPADDR(0xfffffffe)

/*
 * Socket address, internet style.
 */
struct sockaddr_in {
        uint8_t         sin_len;
        sa_family_t     sin_family;
        in_port_t       sin_port;
        struct in_addr  sin_addr;
        __int8_t        sin_zero[8];
};

#define INET_ADDRSTRLEN                 16

/*
 * Structure used to describe IP options.
 * Used to store options internally, to pass them to a process,
 * or to restore options retrieved earlier.
 * The ip_dst is used for the first-hop gateway when using a source route
 * (this gets put into the header proper).
 */
struct ip_opts {
        struct in_addr  ip_dst;         /* first hop, 0 w/o src rt */
#if defined(__cplusplus)
        __int8_t        Ip_opts[40];    /* actually variable in size */
#else
        __int8_t        ip_opts[40];    /* actually variable in size */
#endif
};

/*
 * Options for use with [gs]etsockopt at the IP level.
 * First word of comment is data type; bool is stored in int.
 */
#define IP_OPTIONS              1    /* buf/ip_opts; set/get IP options */
#define IP_HDRINCL              2    /* int; header is included with data */
#define IP_TOS                  3    /* int; IP type of service and preced. */
#define IP_TTL                  4    /* int; IP time to live */
#define IP_RECVOPTS             5    /* bool; receive all IP opts w/dgram */
#define IP_RECVRETOPTS          6    /* bool; receive IP opts for response */
#define IP_RECVDSTADDR          7    /* bool; receive IP dst addr w/dgram */
#define IP_RETOPTS              8    /* ip_opts; set/get IP options */
#define IP_MULTICAST_IF         9    /* in_addr; set/get IP multicast i/f  */
#define IP_MULTICAST_TTL        10   /* u_char; set/get IP multicast ttl */
#define IP_MULTICAST_LOOP       11   /* u_char; set/get IP multicast loopback */
/* The add and drop membership option numbers need to match with the v6 ones */
#define IP_ADD_MEMBERSHIP       12   /* ip_mreq; add an IP group membership */
#define IP_DROP_MEMBERSHIP      13   /* ip_mreq; drop an IP group membership */
#define IP_PORTALGO             18   /* int; port selection algo (rfc6056) */
#define IP_PORTRANGE            19   /* int; range to use for ephemeral port */
#define IP_RECVIF               20   /* bool; receive reception if w/dgram */
#define IP_ERRORMTU             21   /* int; get MTU of last xmit = EMSGSIZE */
#define IP_IPSEC_POLICY         22   /* struct; get/set security policy */
#define IP_RECVTTL              23   /* bool; receive IP TTL w/dgram */
#define IP_MINTTL               24   /* minimum TTL for packet or drop */
#define IP_PKTINFO              25   /* struct; set default src if/addr */
#define IP_RECVPKTINFO          26   /* int; receive dst if/addr w/dgram */
#define IP_BINDANY              27   /* bool: allow bind to any address */
#define IP_SENDSRCADDR IP_RECVDSTADDR /* FreeBSD compatibility */

/*
 * Information sent in the control message of a datagram socket for
 * IP_PKTINFO and IP_RECVPKTINFO.
 */
struct in_pktinfo {
        struct in_addr  ipi_addr;       /* src/dst address */
        unsigned int ipi_ifindex;       /* interface index */
};

#define ipi_spec_dst ipi_addr   /* Solaris/Linux compatibility */

/*
 * Defaults and limits for options
 */
#define IP_DEFAULT_MULTICAST_TTL  1     /* normally limit m'casts to 1 hop  */
#define IP_DEFAULT_MULTICAST_LOOP 1     /* normally hear sends if a member  */
#define IP_MAX_MEMBERSHIPS      20      /* per socket; must fit in one mbuf */

/*
 * Argument structure for IP_ADD_MEMBERSHIP and IP_DROP_MEMBERSHIP.
 */
struct ip_mreq {
        struct  in_addr imr_multiaddr;  /* IP multicast address of group */
        struct  in_addr imr_interface;  /* local IP address of interface */
};

/*
 * Argument for IP_PORTRANGE:
 * - which range to search when port is unspecified at bind() or connect()
 */
#define IP_PORTRANGE_DEFAULT    0       /* default range */
#define IP_PORTRANGE_HIGH       1       /* same as DEFAULT (FreeBSD compat) */
#define IP_PORTRANGE_LOW        2       /* use privileged range */

#if defined(_NETBSD_SOURCE)
/*
 * Definitions for inet sysctl operations.
 *
 * Third level is protocol number.
 * Fourth level is desired variable within that protocol.
 */

/*
 * Names for IP sysctl objects
 */
#define IPCTL_FORWARDING        1       /* act as router */
#define IPCTL_SENDREDIRECTS     2       /* may send redirects when forwarding */
#define IPCTL_DEFTTL            3       /* default TTL */
/* IPCTL_DEFMTU=4, never implemented */
#define IPCTL_FORWSRCRT         5       /* forward source-routed packets */
#define IPCTL_DIRECTEDBCAST     6       /* default broadcast behavior */
#define IPCTL_ALLOWSRCRT        7       /* allow/drop all source-routed pkts */
#define IPCTL_SUBNETSARELOCAL   8       /* treat subnets as local addresses */
#define IPCTL_MTUDISC           9       /* allow path MTU discovery */
#define IPCTL_ANONPORTMIN       10      /* minimum ephemeral port */
#define IPCTL_ANONPORTMAX       11      /* maximum ephemeral port */
#define IPCTL_MTUDISCTIMEOUT    12      /* allow path MTU discovery */
#define IPCTL_MAXFLOWS          13      /* maximum ip flows allowed */
#define IPCTL_HOSTZEROBROADCAST 14      /* is host zero a broadcast addr? */
#define IPCTL_GIF_TTL           15      /* default TTL for gif encap packet */
#define IPCTL_LOWPORTMIN        16      /* minimum reserved port */
#define IPCTL_LOWPORTMAX        17      /* maximum reserved port */
#define IPCTL_MAXFRAGPACKETS    18      /* max packets reassembly queue */
#define IPCTL_GRE_TTL           19      /* default TTL for gre encap packet */
#define IPCTL_CHECKINTERFACE    20      /* drop pkts in from 'wrong' iface */
#define IPCTL_IFQ               21      /* IP packet input queue */
#define IPCTL_RANDOMID          22      /* use random IP ids (if configured) */
#define IPCTL_LOOPBACKCKSUM     23      /* do IP checksum on loopback */
#define IPCTL_STATS             24      /* IP statistics */
#define IPCTL_DAD_COUNT         25      /* DAD packets to send */

#endif /* _NETBSD_SOURCE */

/* INET6 stuff */
#define __KAME_NETINET_IN_H_INCLUDED_
#include <netinet6/in6.h>
#undef __KAME_NETINET_IN_H_INCLUDED_

#ifdef _KERNEL
#include <sys/psref.h>

/*
 * in_cksum_phdr:
 *
 *      Compute significant parts of the IPv4 checksum pseudo-header
 *      for use in a delayed TCP/UDP checksum calculation.
 *
 *      Args:
 *
 *              src             Source IP address
 *              dst             Destination IP address
 *              lenproto        htons(proto-hdr-len + proto-number)
 */
static __inline u_int16_t __unused
in_cksum_phdr(u_int32_t src, u_int32_t dst, u_int32_t lenproto)
{
        u_int32_t sum;

        sum = lenproto +
              (u_int16_t)(src >> 16) +
              (u_int16_t)(src /*& 0xffff*/) +
              (u_int16_t)(dst >> 16) +
              (u_int16_t)(dst /*& 0xffff*/);

        sum = (u_int16_t)(sum >> 16) + (u_int16_t)(sum /*& 0xffff*/);

        if (sum > 0xffff)
                sum -= 0xffff;

        return (sum);
}

/*
 * in_cksum_addword:
 *
 *      Add the two 16-bit network-order values, carry, and return.
 */
static __inline u_int16_t __unused
in_cksum_addword(u_int16_t a, u_int16_t b)
{
        u_int32_t sum = a + b;

        if (sum > 0xffff)
                sum -= 0xffff;

        return (sum);
}

extern  struct in_addr zeroin_addr;
extern  u_char  ip_protox[];
extern const struct sockaddr_in in_any;

int     in_broadcast(struct in_addr, struct ifnet *);
int     in_direct(struct in_addr, struct ifnet *);
int     in_canforward(struct in_addr);
int     cpu_in_cksum(struct mbuf *, int, int, uint32_t);
int     in_cksum(struct mbuf *, int);
int     in4_cksum(struct mbuf *, u_int8_t, int, int);
int     in_localaddr(struct in_addr);
void    in_socktrim(struct sockaddr_in *);

void    in_len2mask(struct in_addr *, u_int);

void    in_if_link_up(struct ifnet *);
void    in_if_link_down(struct ifnet *);
void    in_if_up(struct ifnet *);
void    in_if_down(struct ifnet *);
void    in_if_link_state_change(struct ifnet *, int);

struct route;
struct ip_moptions;

struct in_ifaddr *in_selectsrc(struct sockaddr_in *,
        struct route *, int, struct ip_moptions *, int *, struct psref *);

struct ip;
int in_tunnel_validate(const struct ip *, struct in_addr, struct in_addr);

#define in_hosteq(s,t)  ((s).s_addr == (t).s_addr)
#define in_nullhost(x)  ((x).s_addr == INADDR_ANY)

#define satosin(sa)     ((struct sockaddr_in *)(sa))
#define satocsin(sa)    ((const struct sockaddr_in *)(sa))
#define sintosa(sin)    ((struct sockaddr *)(sin))
#define sintocsa(sin)   ((const struct sockaddr *)(sin))
#define ifatoia(ifa)    ((struct in_ifaddr *)(ifa))

int sockaddr_in_cmp(const struct sockaddr *, const struct sockaddr *);
const void *sockaddr_in_const_addr(const struct sockaddr *, socklen_t *);
void *sockaddr_in_addr(struct sockaddr *, socklen_t *);

static __inline void
sockaddr_in_init1(struct sockaddr_in *sin, const struct in_addr *addr,
    in_port_t port)
{
        sin->sin_port = port;
        sin->sin_addr = *addr;
        memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
}

static __inline void
sockaddr_in_init(struct sockaddr_in *sin, const struct in_addr *addr,
    in_port_t port)
{
        sin->sin_family = AF_INET;
        sin->sin_len = sizeof(*sin);
        sockaddr_in_init1(sin, addr, port);
}

static __inline struct sockaddr *
sockaddr_in_alloc(const struct in_addr *addr, in_port_t port, int flags)
{
        struct sockaddr *sa;

        sa = sockaddr_alloc(AF_INET, sizeof(struct sockaddr_in), flags);

        if (sa == NULL)
                return NULL;

        sockaddr_in_init1(satosin(sa), addr, port);

        return sa;
}
#endif /* _KERNEL */

#if defined(_KERNEL) || defined(_TEST)
int     in_print(char *, size_t, const struct in_addr *);
#define IN_PRINT(b, a)  (in_print((b), sizeof(b), a), (b))
int     sin_print(char *, size_t, const void *);
#endif

#endif /* !_NETINET_IN_H_ */