1/* $OpenBSD: ip6.h,v 1.23 2025/05/27 07:52:49 bluhm Exp $ */
2/* $KAME: ip6.h,v 1.45 2003/06/05 04:46:38 keiichi Exp $ */
3
4/*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33/*
34 * Copyright (c) 1982, 1986, 1993
35 * The Regents of the University of California. All rights reserved.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
45 * 3. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 *
61 * @(#)ip.h 8.1 (Berkeley) 6/10/93
62 */
63
64#ifndef _NETINET_IP6_H_
65#define _NETINET_IP6_H_
66
67/*
68 * Definition for internet protocol version 6.
69 * RFC 2460
70 */
71
72struct ip6_hdr {
73 union {
74 struct ip6_hdrctl {
75 u_int32_t ip6_un1_flow; /* 20 bits of flow-ID */
76 u_int16_t ip6_un1_plen; /* payload length */
77 u_int8_t ip6_un1_nxt; /* next header */
78 u_int8_t ip6_un1_hlim; /* hop limit */
79 } ip6_un1;
80 u_int8_t ip6_un2_vfc; /* 4 bits version, top 4 bits class */
81 } ip6_ctlun;
82 struct in6_addr ip6_src; /* source address */
83 struct in6_addr ip6_dst; /* destination address */
84} __packed;
85
86#define ip6_vfc ip6_ctlun.ip6_un2_vfc
87#define ip6_flow ip6_ctlun.ip6_un1.ip6_un1_flow
88#define ip6_plen ip6_ctlun.ip6_un1.ip6_un1_plen
89#define ip6_nxt ip6_ctlun.ip6_un1.ip6_un1_nxt
90#define ip6_hlim ip6_ctlun.ip6_un1.ip6_un1_hlim
91#define ip6_hops ip6_ctlun.ip6_un1.ip6_un1_hlim
92
93#define IPV6_VERSION 0x60
94#define IPV6_VERSION_MASK 0xf0
95
96#if _BYTE_ORDER == _BIG_ENDIAN
97#define IPV6_FLOWINFO_MASK 0x0fffffff /* flow info (28 bits) */
98#define IPV6_FLOWLABEL_MASK 0x000fffff /* flow label (20 bits) */
99#else
100#if _BYTE_ORDER == _LITTLE_ENDIAN
101#define IPV6_FLOWINFO_MASK 0xffffff0f /* flow info (28 bits) */
102#define IPV6_FLOWLABEL_MASK 0xffff0f00 /* flow label (20 bits) */
103#endif /* _LITTLE_ENDIAN */
104#endif
105#if 1
106/* ECN bits proposed by Sally Floyd */
107#define IP6TOS_CE 0x01 /* congestion experienced */
108#define IP6TOS_ECT 0x02 /* ECN-capable transport */
109#endif
110
111#ifdef _KERNEL
112/*
113 * for IPv6 pseudo header checksum
114 * XXX nonstandard
115 */
116struct ip6_hdr_pseudo {
117 struct in6_addr ip6ph_src;
118 struct in6_addr ip6ph_dst;
119 u_int32_t ip6ph_len;
120 u_int8_t ip6ph_zero[3];
121 u_int8_t ip6ph_nxt;
122} __packed;
123#endif
124
125/*
126 * Extension Headers
127 */
128struct ip6_ext {
129 u_int8_t ip6e_nxt;
130 u_int8_t ip6e_len;
131} __packed;
132
133/* Hop-by-Hop options header */
134/* XXX should we pad it to force alignment on an 8-byte boundary? */
135struct ip6_hbh {
136 u_int8_t ip6h_nxt; /* next header */
137 u_int8_t ip6h_len; /* length in units of 8 octets */
138 /* followed by options */
139} __packed;
140
141/* Destination options header */
142/* XXX should we pad it to force alignment on an 8-byte boundary? */
143struct ip6_dest {
144 u_int8_t ip6d_nxt; /* next header */
145 u_int8_t ip6d_len; /* length in units of 8 octets */
146 /* followed by options */
147} __packed;
148
149/* Option types and related macros */
150#define IP6OPT_PAD1 0x00 /* 00 0 00000 */
151#define IP6OPT_PADN 0x01 /* 00 0 00001 */
152#define IP6OPT_JUMBO 0xC2 /* 11 0 00010 = 194 */
153#define IP6OPT_NSAP_ADDR 0xC3 /* 11 0 00011 */
154#define IP6OPT_TUNNEL_LIMIT 0x04 /* 00 0 00100 */
155#define IP6OPT_ROUTER_ALERT 0x05 /* 00 0 00101 (RFC3542, recommended) */
156
157#define IP6OPT_RTALERT_LEN 4
158#define IP6OPT_RTALERT_MLD 0 /* Datagram contains an MLD message */
159#define IP6OPT_RTALERT_RSVP 1 /* Datagram contains an RSVP message */
160#define IP6OPT_RTALERT_ACTNET 2 /* contains an Active Networks msg */
161#define IP6OPT_MINLEN 2
162
163#define IP6OPT_TYPE(o) ((o) & 0xC0)
164#define IP6OPT_TYPE_SKIP 0x00
165#define IP6OPT_TYPE_DISCARD 0x40
166#define IP6OPT_TYPE_FORCEICMP 0x80
167#define IP6OPT_TYPE_ICMP 0xC0
168
169#define IP6OPT_MUTABLE 0x20
170
171/* IPv6 options: common part */
172struct ip6_opt {
173 u_int8_t ip6o_type;
174 u_int8_t ip6o_len;
175} __packed;
176
177/* Jumbo Payload Option */
178struct ip6_opt_jumbo {
179 u_int8_t ip6oj_type;
180 u_int8_t ip6oj_len;
181 u_int8_t ip6oj_jumbo_len[4];
182} __packed;
183#define IP6OPT_JUMBO_LEN 6
184
185/* NSAP Address Option */
186struct ip6_opt_nsap {
187 u_int8_t ip6on_type;
188 u_int8_t ip6on_len;
189 u_int8_t ip6on_src_nsap_len;
190 u_int8_t ip6on_dst_nsap_len;
191 /* followed by source NSAP */
192 /* followed by destination NSAP */
193} __packed;
194
195/* Tunnel Limit Option */
196struct ip6_opt_tunnel {
197 u_int8_t ip6ot_type;
198 u_int8_t ip6ot_len;
199 u_int8_t ip6ot_encap_limit;
200} __packed;
201
202/* Router Alert Option */
203struct ip6_opt_router {
204 u_int8_t ip6or_type;
205 u_int8_t ip6or_len;
206 u_int8_t ip6or_value[2];
207} __packed;
208/* Router alert values (in network byte order) */
209#if _BYTE_ORDER == _BIG_ENDIAN
210#define IP6_ALERT_MLD 0x0000
211#define IP6_ALERT_RSVP 0x0001
212#define IP6_ALERT_AN 0x0002
213#else
214#if _BYTE_ORDER == _LITTLE_ENDIAN
215#define IP6_ALERT_MLD 0x0000
216#define IP6_ALERT_RSVP 0x0100
217#define IP6_ALERT_AN 0x0200
218#endif /* _LITTLE_ENDIAN */
219#endif
220
221/* Routing header */
222struct ip6_rthdr {
223 u_int8_t ip6r_nxt; /* next header */
224 u_int8_t ip6r_len; /* length in units of 8 octets */
225 u_int8_t ip6r_type; /* routing type */
226 u_int8_t ip6r_segleft; /* segments left */
227 /* followed by routing type specific data */
228} __packed;
229
230/* Type 0 Routing header */
231struct ip6_rthdr0 {
232 u_int8_t ip6r0_nxt; /* next header */
233 u_int8_t ip6r0_len; /* length in units of 8 octets */
234 u_int8_t ip6r0_type; /* always zero */
235 u_int8_t ip6r0_segleft; /* segments left */
236 u_int32_t ip6r0_reserved; /* reserved field */
237} __packed;
238
239/* Fragment header */
240struct ip6_frag {
241 u_int8_t ip6f_nxt; /* next header */
242 u_int8_t ip6f_reserved; /* reserved field */
243 u_int16_t ip6f_offlg; /* offset, reserved, and flag */
244 u_int32_t ip6f_ident; /* identification */
245} __packed;
246
247#if _BYTE_ORDER == _BIG_ENDIAN
248#define IP6F_OFF_MASK 0xfff8 /* mask out offset from _offlg */
249#define IP6F_RESERVED_MASK 0x0006 /* reserved bits in ip6f_offlg */
250#define IP6F_MORE_FRAG 0x0001 /* more-fragments flag */
251#else /* _BYTE_ORDER == _LITTLE_ENDIAN */
252#define IP6F_OFF_MASK 0xf8ff /* mask out offset from _offlg */
253#define IP6F_RESERVED_MASK 0x0600 /* reserved bits in ip6f_offlg */
254#define IP6F_MORE_FRAG 0x0100 /* more-fragments flag */
255#endif /* _BYTE_ORDER == _LITTLE_ENDIAN */
256
257/*
258 * Internet implementation parameters.
259 */
260#define IPV6_MAXHLIM 255 /* maximum hoplimit */
261#define IPV6_DEFHLIM 64 /* default hlim */
262#define IPV6_FRAGTTL 120 /* ttl for fragment packets, in slowtimo tick */
263#define IPV6_HLIMDEC 1 /* subtracted when forwarding */
264
265#define IPV6_MMTU 1280 /* minimal MTU and reassembly. 1024 + 256 */
266#define IPV6_MAXPACKET 65535 /* ip6 max packet size without Jumbo payload*/
267
268#ifdef _KERNEL
269/*
270 * ip6_exthdr_get() ensures that intermediate protocol header (from "off"
271 * to "len") is located in single mbuf, on contiguous memory region.
272 * The pointer to the region will be returned to pointer variable "val",
273 * with type "typ".
274 */
275
276static inline void *
277ip6_exthdr_get(struct mbuf **mp, int off, int len)
278{
279 struct mbuf *t;
280 int toff;
281
282 if ((*mp)->m_len >= off + len)
283 return (mtod(*mp, caddr_t) + off);
284
285 t = m_pulldown(*mp, off, len, &toff);
286 if (t == NULL) {
287 *mp = NULL;
288 return (NULL);
289 }
290 return (mtod(t, caddr_t) + toff);
291}
292#endif /* _KERNEL */
293#endif /* _NETINET_IP6_H_ */