1/* Copyright (C) 1991-2026 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18/* Linux version. */
19
20#ifndef _NETINET_IN_H
21# error "Never use <bits/in.h> directly; include <netinet/in.h> instead."
22#endif
23
24/* If the application has already included linux/in6.h from a linux-based
25 kernel then we will not define the IPv6 IPPROTO_* defines, in6_addr (nor the
26 defines), sockaddr_in6, or ipv6_mreq. Same for in6_ptkinfo or ip6_mtuinfo
27 in linux/ipv6.h. The ABI used by the linux-kernel and glibc match exactly.
28 Neither the linux kernel nor glibc should break this ABI without coordination.
29 In upstream kernel 56c176c9 the _UAPI prefix was stripped so we need to check
30 for _LINUX_IN6_H and _IPV6_H now, and keep checking the old versions for
31 maximum backwards compatibility. */
32#if defined _UAPI_LINUX_IN6_H \
33 || defined _UAPI_IPV6_H \
34 || defined _LINUX_IN6_H \
35 || defined _IPV6_H
36/* This is not quite the same API since the kernel always defines s6_addr16 and
37 s6_addr32. This is not a violation of POSIX since POSIX says "at least the
38 following member" and that holds true. */
39# define __USE_KERNEL_IPV6_DEFS 1
40#else
41# define __USE_KERNEL_IPV6_DEFS 0
42#endif
43
44/* Options for use with `getsockopt' and `setsockopt' at the IP level.
45 The first word in the comment at the right is the data type used;
46 "bool" means a boolean value stored in an `int'. */
47#define IP_OPTIONS 4 /* ip_opts; IP per-packet options. */
48#define IP_HDRINCL 3 /* int; Header is included with data. */
49#define IP_TOS 1 /* int; IP type of service and precedence. */
50#define IP_TTL 2 /* int; IP time to live. */
51#define IP_RECVOPTS 6 /* bool; Receive all IP options w/datagram. */
52/* For BSD compatibility. */
53#define IP_RECVRETOPTS IP_RETOPTS /* bool; Receive IP options for response. */
54#define IP_RETOPTS 7 /* ip_opts; Set/get IP per-packet options. */
55#define IP_MULTICAST_IF 32 /* in_addr; set/get IP multicast i/f */
56#define IP_MULTICAST_TTL 33 /* unsigned char; set/get IP multicast ttl */
57#define IP_MULTICAST_LOOP 34 /* bool; set/get IP multicast loopback */
58#define IP_ADD_MEMBERSHIP 35 /* ip_mreq; add an IP group membership */
59#define IP_DROP_MEMBERSHIP 36 /* ip_mreq; drop an IP group membership */
60#define IP_UNBLOCK_SOURCE 37 /* ip_mreq_source: unblock data from source */
61#define IP_BLOCK_SOURCE 38 /* ip_mreq_source: block data from source */
62#define IP_ADD_SOURCE_MEMBERSHIP 39 /* ip_mreq_source: join source group */
63#define IP_DROP_SOURCE_MEMBERSHIP 40 /* ip_mreq_source: leave source group */
64#define IP_MSFILTER 41
65#ifdef __USE_MISC
66# define MCAST_JOIN_GROUP 42 /* group_req: join any-source group */
67# define MCAST_BLOCK_SOURCE 43 /* group_source_req: block from given group */
68# define MCAST_UNBLOCK_SOURCE 44 /* group_source_req: unblock from given group*/
69# define MCAST_LEAVE_GROUP 45 /* group_req: leave any-source group */
70# define MCAST_JOIN_SOURCE_GROUP 46 /* group_source_req: join source-spec gr */
71# define MCAST_LEAVE_SOURCE_GROUP 47 /* group_source_req: leave source-spec gr*/
72# define MCAST_MSFILTER 48
73# define IP_MULTICAST_ALL 49
74# define IP_UNICAST_IF 50
75
76# define MCAST_EXCLUDE 0
77# define MCAST_INCLUDE 1
78#endif
79
80#define IP_ROUTER_ALERT 5 /* bool */
81#define IP_PKTINFO 8 /* bool */
82#define IP_PKTOPTIONS 9
83#define IP_PMTUDISC 10 /* obsolete name? */
84#define IP_MTU_DISCOVER 10 /* int; see below */
85#define IP_RECVERR 11 /* bool */
86#define IP_RECVTTL 12 /* bool */
87#define IP_RECVTOS 13 /* bool */
88#define IP_MTU 14 /* int */
89#define IP_FREEBIND 15
90#define IP_IPSEC_POLICY 16
91#define IP_XFRM_POLICY 17
92#define IP_PASSSEC 18
93#define IP_TRANSPARENT 19
94#define IP_MULTICAST_ALL 49 /* bool */
95
96/* TProxy original addresses */
97#define IP_ORIGDSTADDR 20
98#define IP_RECVORIGDSTADDR IP_ORIGDSTADDR
99
100#define IP_MINTTL 21
101#define IP_NODEFRAG 22
102#define IP_CHECKSUM 23
103#define IP_BIND_ADDRESS_NO_PORT 24
104#define IP_RECVFRAGSIZE 25
105#define IP_RECVERR_RFC4884 26
106
107/* IP_MTU_DISCOVER arguments. */
108#define IP_PMTUDISC_DONT 0 /* Never send DF frames. */
109#define IP_PMTUDISC_WANT 1 /* Use per route hints. */
110#define IP_PMTUDISC_DO 2 /* Always DF. */
111#define IP_PMTUDISC_PROBE 3 /* Ignore dst pmtu. */
112/* Always use interface mtu (ignores dst pmtu) but don't set DF flag.
113 Also incoming ICMP frag_needed notifications will be ignored on
114 this socket to prevent accepting spoofed ones. */
115#define IP_PMTUDISC_INTERFACE 4
116/* Like IP_PMTUDISC_INTERFACE but allow packets to be fragmented. */
117#define IP_PMTUDISC_OMIT 5
118
119#define IP_MULTICAST_IF 32
120#define IP_MULTICAST_TTL 33
121#define IP_MULTICAST_LOOP 34
122#define IP_ADD_MEMBERSHIP 35
123#define IP_DROP_MEMBERSHIP 36
124#define IP_UNBLOCK_SOURCE 37
125#define IP_BLOCK_SOURCE 38
126#define IP_ADD_SOURCE_MEMBERSHIP 39
127#define IP_DROP_SOURCE_MEMBERSHIP 40
128#define IP_MSFILTER 41
129#define IP_MULTICAST_ALL 49
130#define IP_UNICAST_IF 50
131#define IP_LOCAL_PORT_RANGE 51
132#define IP_PROTOCOL 52
133
134/* To select the IP level. */
135#define SOL_IP 0
136
137#define IP_DEFAULT_MULTICAST_TTL 1
138#define IP_DEFAULT_MULTICAST_LOOP 1
139#define IP_MAX_MEMBERSHIPS 20
140
141#ifdef __USE_MISC
142/* Structure used to describe IP options for IP_OPTIONS and IP_RETOPTS.
143 The `ip_dst' field is used for the first-hop gateway when using a
144 source route (this gets put into the header proper). */
145struct ip_opts
146 {
147 struct in_addr ip_dst; /* First hop; zero without source route. */
148 char ip_opts[40]; /* Actually variable in size. */
149 };
150
151/* Structure used for IP_PKTINFO. */
152struct in_pktinfo
153 {
154 int ipi_ifindex; /* Interface index */
155 struct in_addr ipi_spec_dst; /* Routing destination address */
156 struct in_addr ipi_addr; /* Header destination address */
157 };
158#endif
159
160/* Options for use with `getsockopt' and `setsockopt' at the IPv6 level.
161 The first word in the comment at the right is the data type used;
162 "bool" means a boolean value stored in an `int'. */
163#define IPV6_ADDRFORM 1
164#define IPV6_2292PKTINFO 2
165#define IPV6_2292HOPOPTS 3
166#define IPV6_2292DSTOPTS 4
167#define IPV6_2292RTHDR 5
168#define IPV6_2292PKTOPTIONS 6
169#define IPV6_CHECKSUM 7
170#define IPV6_2292HOPLIMIT 8
171
172#define SCM_SRCRT IPV6_RXSRCRT
173
174#define IPV6_NEXTHOP 9
175#define IPV6_AUTHHDR 10
176#define IPV6_UNICAST_HOPS 16
177#define IPV6_MULTICAST_IF 17
178#define IPV6_MULTICAST_HOPS 18
179#define IPV6_MULTICAST_LOOP 19
180#define IPV6_JOIN_GROUP 20
181#define IPV6_LEAVE_GROUP 21
182#define IPV6_ROUTER_ALERT 22
183#define IPV6_MTU_DISCOVER 23
184#define IPV6_MTU 24
185#define IPV6_RECVERR 25
186#define IPV6_V6ONLY 26
187#define IPV6_JOIN_ANYCAST 27
188#define IPV6_LEAVE_ANYCAST 28
189#define IPV6_MULTICAST_ALL 29
190#define IPV6_ROUTER_ALERT_ISOLATE 30
191#define IPV6_RECVERR_RFC4884 31
192#define IPV6_IPSEC_POLICY 34
193#define IPV6_XFRM_POLICY 35
194#define IPV6_HDRINCL 36
195
196/* Advanced API (RFC3542) (1). */
197#define IPV6_RECVPKTINFO 49
198#define IPV6_PKTINFO 50
199#define IPV6_RECVHOPLIMIT 51
200#define IPV6_HOPLIMIT 52
201#define IPV6_RECVHOPOPTS 53
202#define IPV6_HOPOPTS 54
203#define IPV6_RTHDRDSTOPTS 55
204#define IPV6_RECVRTHDR 56
205#define IPV6_RTHDR 57
206#define IPV6_RECVDSTOPTS 58
207#define IPV6_DSTOPTS 59
208#define IPV6_RECVPATHMTU 60
209#define IPV6_PATHMTU 61
210#define IPV6_DONTFRAG 62
211
212/* Advanced API (RFC3542) (2). */
213#define IPV6_RECVTCLASS 66
214#define IPV6_TCLASS 67
215
216#define IPV6_AUTOFLOWLABEL 70
217
218/* RFC5014. */
219#define IPV6_ADDR_PREFERENCES 72
220
221/* RFC5082. */
222#define IPV6_MINHOPCOUNT 73
223
224#define IPV6_ORIGDSTADDR 74
225#define IPV6_RECVORIGDSTADDR IPV6_ORIGDSTADDR
226#define IPV6_TRANSPARENT 75
227#define IPV6_UNICAST_IF 76
228#define IPV6_RECVFRAGSIZE 77
229#define IPV6_FREEBIND 78
230
231/* Obsolete synonyms for the above. */
232#if !__USE_KERNEL_IPV6_DEFS
233# define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
234# define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
235#endif
236#define IPV6_RXHOPOPTS IPV6_HOPOPTS
237#define IPV6_RXDSTOPTS IPV6_DSTOPTS
238
239/* IPV6_MTU_DISCOVER values. */
240#define IPV6_PMTUDISC_DONT 0 /* Never send DF frames. */
241#define IPV6_PMTUDISC_WANT 1 /* Use per route hints. */
242#define IPV6_PMTUDISC_DO 2 /* Always DF. */
243#define IPV6_PMTUDISC_PROBE 3 /* Ignore dst pmtu. */
244#define IPV6_PMTUDISC_INTERFACE 4 /* See IP_PMTUDISC_INTERFACE. */
245#define IPV6_PMTUDISC_OMIT 5 /* See IP_PMTUDISC_OMIT. */
246
247/* Socket level values for IPv6. */
248#define SOL_IPV6 41
249#define SOL_ICMPV6 58
250
251/* Routing header options for IPv6. */
252#define IPV6_RTHDR_LOOSE 0 /* Hop doesn't need to be neighbour. */
253#define IPV6_RTHDR_STRICT 1 /* Hop must be a neighbour. */
254
255#define IPV6_RTHDR_TYPE_0 0 /* IPv6 Routing header type 0. */