/* $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.
*/
/* 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.
*/
/*
* 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
/*
* 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 */
};
/*
* 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 */
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;
