1/*	$FreeBSD$	*/
2/*	$KAME: ip6.h,v 1.18 2001/03/29 05:34:30 itojun Exp $	*/
3
4/*-
5 * SPDX-License-Identifier: BSD-3-Clause
6 *
7 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the project nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35/*-
36 * Copyright (c) 1982, 1986, 1993
37 *	The Regents of the University of California.  All rights reserved.
38 *
39 * Redistribution and use in source and binary forms, with or without
40 * modification, are permitted provided that the following conditions
41 * are met:
42 * 1. Redistributions of source code must retain the above copyright
43 *    notice, this list of conditions and the following disclaimer.
44 * 2. Redistributions in binary form must reproduce the above copyright
45 *    notice, this list of conditions and the following disclaimer in the
46 *    documentation and/or other materials provided with the distribution.
47 * 3. Neither the name of the University nor the names of its contributors
48 *    may be used to endorse or promote products derived from this software
49 *    without specific prior written permission.
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
52 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
53 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
54 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
55 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
56 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
57 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
58 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
59 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
60 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
61 * SUCH DAMAGE.
62 *
63 *	@(#)ip.h	8.1 (Berkeley) 6/10/93
64 */
65
66#ifndef _NETINET_IP6_H_
67#define _NETINET_IP6_H_
68
69/*
70 * Definition for internet protocol version 6.
71 * RFC 2460
72 */
73
74struct ip6_hdr {
75	union {
76		struct ip6_hdrctl {
77			u_int32_t ip6_un1_flow;	/* 20 bits of flow-ID */
78			u_int16_t ip6_un1_plen;	/* payload length */
79			u_int8_t  ip6_un1_nxt;	/* next header */
80			u_int8_t  ip6_un1_hlim;	/* hop limit */
81		} ip6_un1;
82		u_int8_t ip6_un2_vfc;	/* 4 bits version, top 4 bits class */
83	} ip6_ctlun;
84	struct in6_addr ip6_src;	/* source address */
85	struct in6_addr ip6_dst;	/* destination address */
86} __packed;
87
88#define ip6_vfc		ip6_ctlun.ip6_un2_vfc
89#define ip6_flow	ip6_ctlun.ip6_un1.ip6_un1_flow
90#define ip6_plen	ip6_ctlun.ip6_un1.ip6_un1_plen
91#define ip6_nxt		ip6_ctlun.ip6_un1.ip6_un1_nxt
92#define ip6_hlim	ip6_ctlun.ip6_un1.ip6_un1_hlim
93#define ip6_hops	ip6_ctlun.ip6_un1.ip6_un1_hlim
94
95#define IPV6_VERSION		0x60
96#define IPV6_VERSION_MASK	0xf0
97
98#if BYTE_ORDER == BIG_ENDIAN
99#define IPV6_FLOWINFO_MASK	0x0fffffff	/* flow info (28 bits) */
100#define IPV6_FLOWLABEL_MASK	0x000fffff	/* flow label (20 bits) */
101#else
102#if BYTE_ORDER == LITTLE_ENDIAN
103#define IPV6_FLOWINFO_MASK	0xffffff0f	/* flow info (28 bits) */
104#define IPV6_FLOWLABEL_MASK	0xffff0f00	/* flow label (20 bits) */
105#endif /* LITTLE_ENDIAN */
106#endif
107#define IPV6_FLOWLABEL_LEN	20
108#if 1
109/* ECN bits proposed by Sally Floyd */
110#define IP6TOS_CE		0x01	/* congestion experienced */
111#define IP6TOS_ECT		0x02	/* ECN-capable transport */
112#endif
113
114/*
115 * Extension Headers
116 */
117
118struct	ip6_ext {
119	u_int8_t ip6e_nxt;
120	u_int8_t ip6e_len;
121} __packed;
122
123/* Hop-by-Hop options header */
124/* XXX should we pad it to force alignment on an 8-byte boundary? */
125struct ip6_hbh {
126	u_int8_t ip6h_nxt;	/* next header */
127	u_int8_t ip6h_len;	/* length in units of 8 octets */
128	/* followed by options */
129} __packed;
130
131/* Destination options header */
132/* XXX should we pad it to force alignment on an 8-byte boundary? */
133struct ip6_dest {
134	u_int8_t ip6d_nxt;	/* next header */
135	u_int8_t ip6d_len;	/* length in units of 8 octets */
136	/* followed by options */
137} __packed;
138
139/* Option types and related macros */
140#define IP6OPT_PAD1		0x00	/* 00 0 00000 */
141#define IP6OPT_PADN		0x01	/* 00 0 00001 */
142#define IP6OPT_JUMBO		0xC2	/* 11 0 00010 = 194 */
143#define IP6OPT_NSAP_ADDR	0xC3	/* 11 0 00011 */
144#define IP6OPT_TUNNEL_LIMIT	0x04	/* 00 0 00100 */
145#ifndef _KERNEL
146#define IP6OPT_RTALERT		0x05	/* 00 0 00101 (KAME definition) */
147#endif
148#define IP6OPT_ROUTER_ALERT	0x05	/* 00 0 00101 (RFC3542, recommended) */
149
150#define IP6OPT_RTALERT_LEN	4
151#define IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
152#define IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
153#define IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
154#define IP6OPT_MINLEN		2
155
156#define IP6OPT_EID		0x8a	/* 10 0 01010 */
157
158#define IP6OPT_TYPE(o)		((o) & 0xC0)
159#define IP6OPT_TYPE_SKIP	0x00
160#define IP6OPT_TYPE_DISCARD	0x40
161#define IP6OPT_TYPE_FORCEICMP	0x80
162#define IP6OPT_TYPE_ICMP	0xC0
163
164#define IP6OPT_MUTABLE		0x20
165
166/* IPv6 options: common part */
167struct ip6_opt {
168	u_int8_t ip6o_type;
169	u_int8_t ip6o_len;
170} __packed;
171
172/* Jumbo Payload Option */
173struct ip6_opt_jumbo {
174	u_int8_t ip6oj_type;
175	u_int8_t ip6oj_len;
176	u_int8_t ip6oj_jumbo_len[4];
177} __packed;
178#define IP6OPT_JUMBO_LEN	6
179
180/* NSAP Address Option */
181struct ip6_opt_nsap {
182	u_int8_t ip6on_type;
183	u_int8_t ip6on_len;
184	u_int8_t ip6on_src_nsap_len;
185	u_int8_t ip6on_dst_nsap_len;
186	/* followed by source NSAP */
187	/* followed by destination NSAP */
188} __packed;
189
190/* Tunnel Limit Option */
191struct ip6_opt_tunnel {
192	u_int8_t ip6ot_type;
193	u_int8_t ip6ot_len;
194	u_int8_t ip6ot_encap_limit;
195} __packed;
196
197/* Router Alert Option */
198struct ip6_opt_router {
199	u_int8_t ip6or_type;
200	u_int8_t ip6or_len;
201	u_int8_t ip6or_value[2];
202} __packed;
203/* Router alert values (in network byte order) */
204#if BYTE_ORDER == BIG_ENDIAN
205#define IP6_ALERT_MLD	0x0000
206#define IP6_ALERT_RSVP	0x0001
207#define IP6_ALERT_AN	0x0002
208#else
209#if BYTE_ORDER == LITTLE_ENDIAN
210#define IP6_ALERT_MLD	0x0000
211#define IP6_ALERT_RSVP	0x0100
212#define IP6_ALERT_AN	0x0200
213#endif /* LITTLE_ENDIAN */
214#endif
215
216/* Routing header */
217struct ip6_rthdr {
218	u_int8_t  ip6r_nxt;	/* next header */
219	u_int8_t  ip6r_len;	/* length in units of 8 octets */
220	u_int8_t  ip6r_type;	/* routing type */
221	u_int8_t  ip6r_segleft;	/* segments left */
222	/* followed by routing type specific data */
223} __packed;
224
225/* Type 0 Routing header, deprecated by RFC 5095. */
226struct ip6_rthdr0 {
227	u_int8_t  ip6r0_nxt;		/* next header */
228	u_int8_t  ip6r0_len;		/* length in units of 8 octets */
229	u_int8_t  ip6r0_type;		/* always zero */
230	u_int8_t  ip6r0_segleft;	/* segments left */
231	u_int32_t  ip6r0_reserved;	/* reserved field */
232	/* followed by up to 127 struct in6_addr */
233} __packed;
234
235/* Fragment header */
236struct ip6_frag {
237	u_int8_t  ip6f_nxt;		/* next header */
238	u_int8_t  ip6f_reserved;	/* reserved field */
239	u_int16_t ip6f_offlg;		/* offset, reserved, and flag */
240	u_int32_t ip6f_ident;		/* identification */
241} __packed;
242
243#if BYTE_ORDER == BIG_ENDIAN
244#define IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
245#define IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
246#define IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
247#else /* BYTE_ORDER == LITTLE_ENDIAN */
248#define IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
249#define IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
250#define IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
251#endif /* BYTE_ORDER == LITTLE_ENDIAN */
252
253/*
254 * Internet implementation parameters.
255 */
256#define IPV6_MAXHLIM	255	/* maximum hoplimit */
257#define IPV6_DEFHLIM	64	/* default hlim */
258#define IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
259#define IPV6_HLIMDEC	1	/* subtracted when forwarding */
260
261#define IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
262#define IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
263#define IPV6_MAXOPTHDR	2048	/* max option header size, 256 64-bit words */
264
265#ifdef _KERNEL
266/*
267 * IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
268 * target header (including IPv6 itself, extension headers and
269 * TCP/UDP/ICMP6 headers) are contiguous. KAME requires drivers
270 * to store incoming data into one internal mbuf or one or more external
271 * mbufs(never into two or more internal mbufs). Thus, the third case is
272 * supposed to never be matched but is prepared just in case.
273 */
274
275#define IP6_EXTHDR_CHECK(m, off, hlen, ret)				\
276do {									\
277    if ((m)->m_next != NULL) {						\
278	if (((m)->m_flags & M_LOOP) &&					\
279	    ((m)->m_len < (off) + (hlen)) &&				\
280	    (((m) = m_pullup((m), (off) + (hlen))) == NULL)) {		\
281		IP6STAT_INC(ip6s_exthdrtoolong);				\
282		return ret;						\
283	} else {							\
284		if ((m)->m_len < (off) + (hlen)) {			\
285			IP6STAT_INC(ip6s_exthdrtoolong);			\
286			m_freem(m);					\
287			return ret;					\
288		}							\
289	}								\
290    } else {								\
291	if ((m)->m_len < (off) + (hlen)) {				\
292		IP6STAT_INC(ip6s_tooshort);				\
293		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);	\
294		m_freem(m);						\
295		return ret;						\
296	}								\
297    }									\
298} while (/*CONSTCOND*/ 0)
299
300/*
301 * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
302 * "len") is located in single mbuf, on contiguous memory region.
303 * The pointer to the region will be returned to pointer variable "val",
304 * with type "typ".
305 * IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
306 * very top of mbuf.  GET0 is likely to make memory copy than GET.
307 *
308 * XXX we're now testing this, needs m_pulldown()
309 */
310#define IP6_EXTHDR_GET(val, typ, m, off, len) \
311do {									\
312	struct mbuf *t;							\
313	int tmp;							\
314	if ((m)->m_len >= (off) + (len))				\
315		(val) = (typ)(mtod((m), caddr_t) + (off));		\
316	else {								\
317		t = m_pulldown((m), (off), (len), &tmp);		\
318		if (t) {						\
319			if (t->m_len < tmp + (len))			\
320				panic("m_pulldown malfunction");	\
321			(val) = (typ)(mtod(t, caddr_t) + tmp);		\
322		} else {						\
323			(val) = (typ)NULL;				\
324			(m) = NULL;					\
325		}							\
326	}								\
327} while (/*CONSTCOND*/ 0)
328
329#define IP6_EXTHDR_GET0(val, typ, m, off, len) \
330do {									\
331	struct mbuf *t;							\
332	if ((off) == 0)							\
333		(val) = (typ)mtod(m, caddr_t);				\
334	else {								\
335		t = m_pulldown((m), (off), (len), NULL);		\
336		if (t) {						\
337			if (t->m_len < (len))				\
338				panic("m_pulldown malfunction");	\
339			(val) = (typ)mtod(t, caddr_t);			\
340		} else {						\
341			(val) = (typ)NULL;				\
342			(m) = NULL;					\
343		}							\
344	}								\
345} while (/*CONSTCOND*/ 0)
346
347#endif /*_KERNEL*/
348
349#endif /* not _NETINET_IP6_H_ */
350