1/*	$FreeBSD: stable/11/sys/netinet/ip6.h 346755 2019-04-26 17:01:56Z mav $	*/
2/*	$KAME: ip6.h,v 1.18 2001/03/29 05:34:30 itojun 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 * 4. 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#define IPV6_FLOWLABEL_LEN	20
106#if 1
107/* ECN bits proposed by Sally Floyd */
108#define IP6TOS_CE		0x01	/* congestion experienced */
109#define IP6TOS_ECT		0x02	/* ECN-capable transport */
110#endif
111
112/*
113 * Extension Headers
114 */
115
116struct	ip6_ext {
117	u_int8_t ip6e_nxt;
118	u_int8_t ip6e_len;
119} __packed;
120
121/* Hop-by-Hop options header */
122/* XXX should we pad it to force alignment on an 8-byte boundary? */
123struct ip6_hbh {
124	u_int8_t ip6h_nxt;	/* next header */
125	u_int8_t ip6h_len;	/* length in units of 8 octets */
126	/* followed by options */
127} __packed;
128
129/* Destination options header */
130/* XXX should we pad it to force alignment on an 8-byte boundary? */
131struct ip6_dest {
132	u_int8_t ip6d_nxt;	/* next header */
133	u_int8_t ip6d_len;	/* length in units of 8 octets */
134	/* followed by options */
135} __packed;
136
137/* Option types and related macros */
138#define IP6OPT_PAD1		0x00	/* 00 0 00000 */
139#define IP6OPT_PADN		0x01	/* 00 0 00001 */
140#define IP6OPT_JUMBO		0xC2	/* 11 0 00010 = 194 */
141#define IP6OPT_NSAP_ADDR	0xC3	/* 11 0 00011 */
142#define IP6OPT_TUNNEL_LIMIT	0x04	/* 00 0 00100 */
143#ifndef _KERNEL
144#define IP6OPT_RTALERT		0x05	/* 00 0 00101 (KAME definition) */
145#endif
146#define IP6OPT_ROUTER_ALERT	0x05	/* 00 0 00101 (RFC3542, recommended) */
147
148#define IP6OPT_RTALERT_LEN	4
149#define IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
150#define IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
151#define IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
152#define IP6OPT_MINLEN		2
153
154#define IP6OPT_EID		0x8a	/* 10 0 01010 */
155
156#define IP6OPT_TYPE(o)		((o) & 0xC0)
157#define IP6OPT_TYPE_SKIP	0x00
158#define IP6OPT_TYPE_DISCARD	0x40
159#define IP6OPT_TYPE_FORCEICMP	0x80
160#define IP6OPT_TYPE_ICMP	0xC0
161
162#define IP6OPT_MUTABLE		0x20
163
164/* IPv6 options: common part */
165struct ip6_opt {
166	u_int8_t ip6o_type;
167	u_int8_t ip6o_len;
168} __packed;
169
170/* Jumbo Payload Option */
171struct ip6_opt_jumbo {
172	u_int8_t ip6oj_type;
173	u_int8_t ip6oj_len;
174	u_int8_t ip6oj_jumbo_len[4];
175} __packed;
176#define IP6OPT_JUMBO_LEN	6
177
178/* NSAP Address Option */
179struct ip6_opt_nsap {
180	u_int8_t ip6on_type;
181	u_int8_t ip6on_len;
182	u_int8_t ip6on_src_nsap_len;
183	u_int8_t ip6on_dst_nsap_len;
184	/* followed by source NSAP */
185	/* followed by destination NSAP */
186} __packed;
187
188/* Tunnel Limit Option */
189struct ip6_opt_tunnel {
190	u_int8_t ip6ot_type;
191	u_int8_t ip6ot_len;
192	u_int8_t ip6ot_encap_limit;
193} __packed;
194
195/* Router Alert Option */
196struct ip6_opt_router {
197	u_int8_t ip6or_type;
198	u_int8_t ip6or_len;
199	u_int8_t ip6or_value[2];
200} __packed;
201/* Router alert values (in network byte order) */
202#if BYTE_ORDER == BIG_ENDIAN
203#define IP6_ALERT_MLD	0x0000
204#define IP6_ALERT_RSVP	0x0001
205#define IP6_ALERT_AN	0x0002
206#else
207#if BYTE_ORDER == LITTLE_ENDIAN
208#define IP6_ALERT_MLD	0x0000
209#define IP6_ALERT_RSVP	0x0100
210#define IP6_ALERT_AN	0x0200
211#endif /* LITTLE_ENDIAN */
212#endif
213
214/* Routing header */
215struct ip6_rthdr {
216	u_int8_t  ip6r_nxt;	/* next header */
217	u_int8_t  ip6r_len;	/* length in units of 8 octets */
218	u_int8_t  ip6r_type;	/* routing type */
219	u_int8_t  ip6r_segleft;	/* segments left */
220	/* followed by routing type specific data */
221} __packed;
222
223/* Type 0 Routing header, deprecated by RFC 5095. */
224struct ip6_rthdr0 {
225	u_int8_t  ip6r0_nxt;		/* next header */
226	u_int8_t  ip6r0_len;		/* length in units of 8 octets */
227	u_int8_t  ip6r0_type;		/* always zero */
228	u_int8_t  ip6r0_segleft;	/* segments left */
229	u_int32_t  ip6r0_reserved;	/* reserved field */
230	/* followed by up to 127 struct in6_addr */
231} __packed;
232
233/* Fragment header */
234struct ip6_frag {
235	u_int8_t  ip6f_nxt;		/* next header */
236	u_int8_t  ip6f_reserved;	/* reserved field */
237	u_int16_t ip6f_offlg;		/* offset, reserved, and flag */
238	u_int32_t ip6f_ident;		/* identification */
239} __packed;
240
241#if BYTE_ORDER == BIG_ENDIAN
242#define IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
243#define IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
244#define IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
245#else /* BYTE_ORDER == LITTLE_ENDIAN */
246#define IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
247#define IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
248#define IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
249#endif /* BYTE_ORDER == LITTLE_ENDIAN */
250
251/*
252 * Internet implementation parameters.
253 */
254#define IPV6_MAXHLIM	255	/* maximum hoplimit */
255#define IPV6_DEFHLIM	64	/* default hlim */
256#define IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
257#define IPV6_HLIMDEC	1	/* subtracted when forwarding */
258
259#define IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
260#define IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
261#define IPV6_MAXOPTHDR	2048	/* max option header size, 256 64-bit words */
262
263#ifdef _KERNEL
264/*
265 * IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
266 * target header (including IPv6 itself, extension headers and
267 * TCP/UDP/ICMP6 headers) are contiguous. KAME requires drivers
268 * to store incoming data into one internal mbuf or one or more external
269 * mbufs(never into two or more internal mbufs). Thus, the third case is
270 * supposed to never be matched but is prepared just in case.
271 */
272
273#define IP6_EXTHDR_CHECK(m, off, hlen, ret)				\
274do {									\
275    if ((m)->m_next != NULL) {						\
276	if (((m)->m_flags & M_LOOP) &&					\
277	    ((m)->m_len < (off) + (hlen)) &&				\
278	    (((m) = m_pullup((m), (off) + (hlen))) == NULL)) {		\
279		IP6STAT_INC(ip6s_exthdrtoolong);				\
280		return ret;						\
281	} else {							\
282		if ((m)->m_len < (off) + (hlen)) {			\
283			IP6STAT_INC(ip6s_exthdrtoolong);			\
284			m_freem(m);					\
285			return ret;					\
286		}							\
287	}								\
288    } else {								\
289	if ((m)->m_len < (off) + (hlen)) {				\
290		IP6STAT_INC(ip6s_tooshort);				\
291		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);	\
292		m_freem(m);						\
293		return ret;						\
294	}								\
295    }									\
296} while (/*CONSTCOND*/ 0)
297
298/*
299 * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
300 * "len") is located in single mbuf, on contiguous memory region.
301 * The pointer to the region will be returned to pointer variable "val",
302 * with type "typ".
303 * IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
304 * very top of mbuf.  GET0 is likely to make memory copy than GET.
305 *
306 * XXX we're now testing this, needs m_pulldown()
307 */
308#define IP6_EXTHDR_GET(val, typ, m, off, len) \
309do {									\
310	struct mbuf *t;							\
311	int tmp;							\
312	if ((m)->m_len >= (off) + (len))				\
313		(val) = (typ)(mtod((m), caddr_t) + (off));		\
314	else {								\
315		t = m_pulldown((m), (off), (len), &tmp);		\
316		if (t) {						\
317			if (t->m_len < tmp + (len))			\
318				panic("m_pulldown malfunction");	\
319			(val) = (typ)(mtod(t, caddr_t) + tmp);		\
320		} else {						\
321			(val) = (typ)NULL;				\
322			(m) = NULL;					\
323		}							\
324	}								\
325} while (/*CONSTCOND*/ 0)
326
327#define IP6_EXTHDR_GET0(val, typ, m, off, len) \
328do {									\
329	struct mbuf *t;							\
330	if ((off) == 0)							\
331		(val) = (typ)mtod(m, caddr_t);				\
332	else {								\
333		t = m_pulldown((m), (off), (len), NULL);		\
334		if (t) {						\
335			if (t->m_len < (len))				\
336				panic("m_pulldown malfunction");	\
337			(val) = (typ)mtod(t, caddr_t);			\
338		} else {						\
339			(val) = (typ)NULL;				\
340			(m) = NULL;					\
341		}							\
342	}								\
343} while (/*CONSTCOND*/ 0)
344
345#endif /*_KERNEL*/
346
347#endif /* not _NETINET_IP6_H_ */
348