The C and C++ Include Header Files

/usr/include/linux/ipv6.h


$ cat -n /usr/include/linux/ipv6.h

     1	/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
     2	#ifndef _IPV6_H
     3	#define _IPV6_H
     4	
     5	#include <linux/libc-compat.h>
     6	#include <linux/types.h>
     7	#include <linux/stddef.h>
     8	#include <linux/in6.h>
     9	#include <asm/byteorder.h>
    10	
    11	/* The latest drafts declared increase in minimal mtu up to 1280. */
    12	
    13	#define IPV6_MIN_MTU	1280
    14	
    15	/*
    16	 *	Advanced API
    17	 *	source interface/address selection, source routing, etc...
    18	 *	*under construction*
    19	 */
    20	
    21	#if __UAPI_DEF_IN6_PKTINFO
    22	struct in6_pktinfo {
    23		struct in6_addr	ipi6_addr;
    24		int		ipi6_ifindex;
    25	};
    26	#endif
    27	
    28	#if __UAPI_DEF_IP6_MTUINFO
    29	struct ip6_mtuinfo {
    30		struct sockaddr_in6	ip6m_addr;
    31		__u32			ip6m_mtu;
    32	};
    33	#endif
    34	
    35	struct in6_ifreq {
    36		struct in6_addr	ifr6_addr;
    37		__u32		ifr6_prefixlen;
    38		int		ifr6_ifindex; 
    39	};
    40	
    41	#define IPV6_SRCRT_STRICT	0x01	/* Deprecated; will be removed */
    42	#define IPV6_SRCRT_TYPE_0	0	/* Deprecated; will be removed */
    43	#define IPV6_SRCRT_TYPE_2	2	/* IPv6 type 2 Routing Header	*/
    44	#define IPV6_SRCRT_TYPE_3	3	/* RPL Segment Routing with IPv6 */
    45	#define IPV6_SRCRT_TYPE_4	4	/* Segment Routing with IPv6 */
    46	
    47	/*
    48	 *	routing header
    49	 */
    50	struct ipv6_rt_hdr {
    51		__u8		nexthdr;
    52		__u8		hdrlen;
    53		__u8		type;
    54		__u8		segments_left;
    55	
    56		/*
    57		 *	type specific data
    58		 *	variable length field
    59		 */
    60	};
    61	
    62	
    63	struct ipv6_opt_hdr {
    64		__u8 		nexthdr;
    65		__u8 		hdrlen;
    66		/* 
    67		 * TLV encoded option data follows.
    68		 */
    69	} __attribute__((packed));	/* required for some archs */
    70	
    71	#define ipv6_destopt_hdr ipv6_opt_hdr
    72	#define ipv6_hopopt_hdr  ipv6_opt_hdr
    73	
    74	/* Router Alert option values (RFC2711) */
    75	#define IPV6_OPT_ROUTERALERT_MLD	0x0000	/* MLD(RFC2710) */
    76	
    77	/*
    78	 *	routing header type 0 (used in cmsghdr struct)
    79	 */
    80	
    81	struct rt0_hdr {
    82		struct ipv6_rt_hdr	rt_hdr;
    83		__u32			reserved;
    84		struct in6_addr		addr[];
    85	
    86	#define rt0_type		rt_hdr.type
    87	};
    88	
    89	/*
    90	 *	routing header type 2
    91	 */
    92	
    93	struct rt2_hdr {
    94		struct ipv6_rt_hdr	rt_hdr;
    95		__u32			reserved;
    96		struct in6_addr		addr;
    97	
    98	#define rt2_type		rt_hdr.type
    99	};
   100	
   101	/*
   102	 *	home address option in destination options header
   103	 */
   104	
   105	struct ipv6_destopt_hao {
   106		__u8			type;
   107		__u8			length;
   108		struct in6_addr		addr;
   109	} __attribute__((packed));
   110	
   111	/*
   112	 *	IPv6 fixed header
   113	 *
   114	 *	BEWARE, it is incorrect. The first 4 bits of flow_lbl
   115	 *	are glued to priority now, forming "class".
   116	 */
   117	
   118	struct ipv6hdr {
   119	#if defined(__LITTLE_ENDIAN_BITFIELD)
   120		__u8			priority:4,
   121					version:4;
   122	#elif defined(__BIG_ENDIAN_BITFIELD)
   123		__u8			version:4,
   124					priority:4;
   125	#else
   126	#error	"Please fix <asm/byteorder.h>"
   127	#endif
   128		__u8			flow_lbl[3];
   129	
   130		__be16			payload_len;
   131		__u8			nexthdr;
   132		__u8			hop_limit;
   133	
   134		__struct_group(/* no tag */, addrs, /* no attrs */,
   135			struct	in6_addr	saddr;
   136			struct	in6_addr	daddr;
   137		);
   138	};
   139	
   140	
   141	/* index values for the variables in ipv6_devconf */
   142	enum {
   143		DEVCONF_FORWARDING = 0,
   144		DEVCONF_HOPLIMIT,
   145		DEVCONF_MTU6,
   146		DEVCONF_ACCEPT_RA,
   147		DEVCONF_ACCEPT_REDIRECTS,
   148		DEVCONF_AUTOCONF,
   149		DEVCONF_DAD_TRANSMITS,
   150		DEVCONF_RTR_SOLICITS,
   151		DEVCONF_RTR_SOLICIT_INTERVAL,
   152		DEVCONF_RTR_SOLICIT_DELAY,
   153		DEVCONF_USE_TEMPADDR,
   154		DEVCONF_TEMP_VALID_LFT,
   155		DEVCONF_TEMP_PREFERED_LFT,
   156		DEVCONF_REGEN_MAX_RETRY,
   157		DEVCONF_MAX_DESYNC_FACTOR,
   158		DEVCONF_MAX_ADDRESSES,
   159		DEVCONF_FORCE_MLD_VERSION,
   160		DEVCONF_ACCEPT_RA_DEFRTR,
   161		DEVCONF_ACCEPT_RA_PINFO,
   162		DEVCONF_ACCEPT_RA_RTR_PREF,
   163		DEVCONF_RTR_PROBE_INTERVAL,
   164		DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN,
   165		DEVCONF_PROXY_NDP,
   166		DEVCONF_OPTIMISTIC_DAD,
   167		DEVCONF_ACCEPT_SOURCE_ROUTE,
   168		DEVCONF_MC_FORWARDING,
   169		DEVCONF_DISABLE_IPV6,
   170		DEVCONF_ACCEPT_DAD,
   171		DEVCONF_FORCE_TLLAO,
   172		DEVCONF_NDISC_NOTIFY,
   173		DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL,
   174		DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL,
   175		DEVCONF_SUPPRESS_FRAG_NDISC,
   176		DEVCONF_ACCEPT_RA_FROM_LOCAL,
   177		DEVCONF_USE_OPTIMISTIC,
   178		DEVCONF_ACCEPT_RA_MTU,
   179		DEVCONF_STABLE_SECRET,
   180		DEVCONF_USE_OIF_ADDRS_ONLY,
   181		DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT,
   182		DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN,
   183		DEVCONF_DROP_UNICAST_IN_L2_MULTICAST,
   184		DEVCONF_DROP_UNSOLICITED_NA,
   185		DEVCONF_KEEP_ADDR_ON_DOWN,
   186		DEVCONF_RTR_SOLICIT_MAX_INTERVAL,
   187		DEVCONF_SEG6_ENABLED,
   188		DEVCONF_SEG6_REQUIRE_HMAC,
   189		DEVCONF_ENHANCED_DAD,
   190		DEVCONF_ADDR_GEN_MODE,
   191		DEVCONF_DISABLE_POLICY,
   192		DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN,
   193		DEVCONF_NDISC_TCLASS,
   194		DEVCONF_RPL_SEG_ENABLED,
   195		DEVCONF_RA_DEFRTR_METRIC,
   196		DEVCONF_IOAM6_ENABLED,
   197		DEVCONF_IOAM6_ID,
   198		DEVCONF_IOAM6_ID_WIDE,
   199		DEVCONF_NDISC_EVICT_NOCARRIER,
   200		DEVCONF_ACCEPT_UNTRACKED_NA,
   201		DEVCONF_ACCEPT_RA_MIN_LFT,
   202		DEVCONF_MAX
   203	};
   204	
   205	
   206	#endif /* _IPV6_H */