in.h

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/* Copyright (C) 1991-1999, 2000, 2004 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

/* Linux version.  */

#ifndef _NETINET_IN_H
# error "Never use <bits/in.h> directly; include <netinet/in.h> instead."
#endif

/* Options for use with `getsockopt' and `setsockopt' at the IP level.
   The first word in the comment at the right is the data type used;
   "bool" means a boolean value stored in an `int'.  */
#define        IP_OPTIONS      4       /* ip_opts; IP per-packet options.  */
#define        IP_HDRINCL      3       /* int; Header is included with data.  */
#define        IP_TOS          1       /* int; IP type of service and precedence.  */
#define        IP_TTL          2       /* int; IP time to live.  */
#define        IP_RECVOPTS     6       /* bool; Receive all IP options w/datagram.  */
/* For BSD compatibility.  */
#define        IP_RECVRETOPTS  IP_RETOPTS       /* bool; Receive IP options for response.  */
#define        IP_RETOPTS      7       /* ip_opts; Set/get IP per-packet options.  */
#define IP_MULTICAST_IF 32	/* in_addr; set/get IP multicast i/f */
#define IP_MULTICAST_TTL 33	/* u_char; set/get IP multicast ttl */
#define IP_MULTICAST_LOOP 34	/* i_char; set/get IP multicast loopback */
#define IP_ADD_MEMBERSHIP 35	/* ip_mreq; add an IP group membership */
#define IP_DROP_MEMBERSHIP 36	/* ip_mreq; drop an IP group membership */
#define IP_UNBLOCK_SOURCE 37	/* ip_mreq_source: unblock data from source */
#define IP_BLOCK_SOURCE 38	/* ip_mreq_source: block data from source */
#define IP_ADD_SOURCE_MEMBERSHIP 39 /* ip_mreq_source: join source group */
#define IP_DROP_SOURCE_MEMBERSHIP 40 /* ip_mreq_source: leave source group */
#define IP_MSFILTER 41
#define MCAST_JOIN_GROUP 42	/* group_req: join any-source group */
#define MCAST_BLOCK_SOURCE 43	/* group_source_req: block from given group */
#define MCAST_UNBLOCK_SOURCE 44	/* group_source_req: unblock from given group*/
#define MCAST_LEAVE_GROUP 45	/* group_req: leave any-source group */
#define MCAST_JOIN_SOURCE_GROUP 46 /* group_source_req: join source-spec gr */
#define MCAST_LEAVE_SOURCE_GROUP 47 /* group_source_req: leave source-spec gr*/
#define MCAST_MSFILTER 48

#define MCAST_EXCLUDE   0
#define MCAST_INCLUDE   1

#define IP_ROUTER_ALERT    5	/* bool */
#define IP_PKTINFO         8	/* bool */
#define IP_PKTOPTIONS      9
#define IP_PMTUDISC        10	/* obsolete name? */
#define IP_MTU_DISCOVER    10	/* int; see below */
#define IP_RECVERR         11	/* bool */
#define IP_RECVTTL         12	/* bool */
#define IP_RECVTOS         13	/* bool */


/* IP_MTU_DISCOVER arguments.  */
#define IP_PMTUDISC_DONT   0	/* Never send DF frames.  */
#define IP_PMTUDISC_WANT   1	/* Use per route hints.  */
#define IP_PMTUDISC_DO     2	/* Always DF.  */

/* To select the IP level.  */
#define SOL_IP	0

#define IP_DEFAULT_MULTICAST_TTL        1
#define IP_DEFAULT_MULTICAST_LOOP       1
#define IP_MAX_MEMBERSHIPS              20

/* Structure used to describe IP options for IP_OPTIONS and IP_RETOPTS.
   The `ip_dst' field 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; zero without source route.  */
    char ip_opts[40];		/* Actually variable in size.  */
  };

/* Like `struct ip_mreq' but including interface specification by index.  */
struct ip_mreqn
  {
    struct in_addr imr_multiaddr;	/* IP multicast address of group */
    struct in_addr imr_address;		/* local IP address of interface */
    int	imr_ifindex;			/* Interface index */
  };

/* Structure used for IP_PKTINFO.  */
struct in_pktinfo
  {
    int ipi_ifindex;			/* Interface index  */
    struct in_addr ipi_spec_dst;	/* Routing destination address  */
    struct in_addr ipi_addr;		/* Header destination address  */
  };

/* Options for use with `getsockopt' and `setsockopt' at the IPv6 level.
   The first word in the comment at the right is the data type used;
   "bool" means a boolean value stored in an `int'.  */
#define IPV6_ADDRFORM		1
#define IPV6_2292PKTINFO	2
#define IPV6_2292HOPOPTS	3
#define IPV6_2292DSTOPTS	4
#define IPV6_2292RTHDR		5
#define IPV6_2292PKTOPTIONS	6
#define IPV6_CHECKSUM		7
#define IPV6_2292HOPLIMIT	8

#define SCM_SRCRT		IPV6_RXSRCRT

#define IPV6_NEXTHOP		9
#define IPV6_AUTHHDR		10
#define IPV6_UNICAST_HOPS	16
#define IPV6_MULTICAST_IF	17
#define IPV6_MULTICAST_HOPS	18
#define IPV6_MULTICAST_LOOP	19
#define IPV6_JOIN_GROUP		20
#define IPV6_LEAVE_GROUP	21
#define IPV6_ROUTER_ALERT	22
#define IPV6_MTU_DISCOVER	23
#define IPV6_MTU		24
#define IPV6_RECVERR		25
#define IPV6_V6ONLY		26
#define IPV6_JOIN_ANYCAST	27
#define IPV6_LEAVE_ANYCAST	28
#define IPV6_IPSEC_POLICY	34
#define IPV6_XFRM_POLICY	35

#define IPV6_RECVPKTINFO	49
#define IPV6_PKTINFO		50
#define IPV6_RECVHOPLIMIT	51
#define IPV6_HOPLIMIT		52
#define IPV6_RECVHOPOPTS	53
#define IPV6_HOPOPTS		54
#define IPV6_RTHDRDSTOPTS	55
#define IPV6_RECVRTHDR		56
#define IPV6_RTHDR		57
#define IPV6_RECVDSTOPTS	58
#define IPV6_DSTOPTS		59

#define IPV6_RECVTCLASS		66
#define IPV6_TCLASS		67

/* Obsolete synonyms for the above.  */
#define IPV6_ADD_MEMBERSHIP	IPV6_JOIN_GROUP
#define IPV6_DROP_MEMBERSHIP	IPV6_LEAVE_GROUP
#define IPV6_RXHOPOPTS		IPV6_HOPOPTS
#define IPV6_RXDSTOPTS		IPV6_DSTOPTS

/* IPV6_MTU_DISCOVER values.  */
#define IPV6_PMTUDISC_DONT	0	/* Never send DF frames.  */
#define IPV6_PMTUDISC_WANT	1	/* Use per route hints.  */
#define IPV6_PMTUDISC_DO	2	/* Always DF.  */

/* Socket level values for IPv6.  */
#define SOL_IPV6        41
#define SOL_ICMPV6      58

/* Routing header options for IPv6.  */
#define IPV6_RTHDR_LOOSE	0	/* Hop doesn't need to be neighbour. */
#define IPV6_RTHDR_STRICT	1	/* Hop must be a neighbour.  */

#define IPV6_RTHDR_TYPE_0	0	/* IPv6 Routing header type 0.  */