1/* Copyright (C) 1991-2025 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.  */