xref: /netbsd/sys/netinet/ip6.h (revision c4a72b64)
1 /*	$NetBSD: ip6.h,v 1.13 2002/11/02 07:28:12 perry Exp $	*/
2 /*	$KAME: ip6.h,v 1.14 2000/10/09 01:04:09 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  * 3. All advertising materials mentioning features or use of this software
46  *    must display the following acknowledgement:
47  *	This product includes software developed by the University of
48  *	California, Berkeley and its contributors.
49  * 4. Neither the name of the University nor the names of its contributors
50  *    may be used to endorse or promote products derived from this software
51  *    without specific prior written permission.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63  * SUCH DAMAGE.
64  *
65  *	@(#)ip.h	8.1 (Berkeley) 6/10/93
66  */
67 
68 #ifndef _NETINET_IP6_H_
69 #define _NETINET_IP6_H_
70 
71 /*
72  * Definition for internet protocol version 6.
73  * RFC 2460
74  */
75 
76 struct ip6_hdr {
77 	union {
78 		struct ip6_hdrctl {
79 			u_int32_t ip6_un1_flow;	/* 20 bits of flow-ID */
80 			u_int16_t ip6_un1_plen;	/* payload length */
81 			u_int8_t  ip6_un1_nxt;	/* next header */
82 			u_int8_t  ip6_un1_hlim;	/* hop limit */
83 		} ip6_un1;
84 		u_int8_t ip6_un2_vfc;	/* 4 bits version, top 4 bits class */
85 	} ip6_ctlun;
86 	struct in6_addr ip6_src;	/* source address */
87 	struct in6_addr ip6_dst;	/* destination address */
88 } __attribute__((__packed__));
89 
90 #define ip6_vfc		ip6_ctlun.ip6_un2_vfc
91 #define ip6_flow	ip6_ctlun.ip6_un1.ip6_un1_flow
92 #define ip6_plen	ip6_ctlun.ip6_un1.ip6_un1_plen
93 #define ip6_nxt		ip6_ctlun.ip6_un1.ip6_un1_nxt
94 #define ip6_hlim	ip6_ctlun.ip6_un1.ip6_un1_hlim
95 #define ip6_hops	ip6_ctlun.ip6_un1.ip6_un1_hlim
96 
97 #define IPV6_VERSION		0x60
98 #define IPV6_VERSION_MASK	0xf0
99 
100 #if BYTE_ORDER == BIG_ENDIAN
101 #define IPV6_FLOWINFO_MASK	0x0fffffff	/* flow info (28 bits) */
102 #define IPV6_FLOWLABEL_MASK	0x000fffff	/* flow label (20 bits) */
103 #else
104 #if BYTE_ORDER == LITTLE_ENDIAN
105 #define IPV6_FLOWINFO_MASK	0xffffff0f	/* flow info (28 bits) */
106 #define IPV6_FLOWLABEL_MASK	0xffff0f00	/* flow label (20 bits) */
107 #endif /* LITTLE_ENDIAN */
108 #endif
109 #if 1
110 /* ECN bits proposed by Sally Floyd */
111 #define IP6TOS_CE		0x01	/* congestion experienced */
112 #define IP6TOS_ECT		0x02	/* ECN-capable transport */
113 #endif
114 
115 /*
116  * Extension Headers
117  */
118 
119 struct	ip6_ext {
120 	u_int8_t ip6e_nxt;
121 	u_int8_t ip6e_len;
122 } __attribute__((__packed__));
123 
124 /* Hop-by-Hop options header */
125 /* XXX should we pad it to force alignment on an 8-byte boundary? */
126 struct ip6_hbh {
127 	u_int8_t ip6h_nxt;	/* next header */
128 	u_int8_t ip6h_len;	/* length in units of 8 octets */
129 	/* followed by options */
130 } __attribute__((__packed__));
131 
132 /* Destination options header */
133 /* XXX should we pad it to force alignment on an 8-byte boundary? */
134 struct ip6_dest {
135 	u_int8_t ip6d_nxt;	/* next header */
136 	u_int8_t ip6d_len;	/* length in units of 8 octets */
137 	/* followed by options */
138 } __attribute__((__packed__));
139 
140 /* Option types and related macros */
141 #define IP6OPT_PAD1		0x00	/* 00 0 00000 */
142 #define IP6OPT_PADN		0x01	/* 00 0 00001 */
143 #define IP6OPT_JUMBO		0xC2	/* 11 0 00010 = 194 */
144 #define IP6OPT_JUMBO_LEN	6
145 #define IP6OPT_RTALERT		0x05	/* 00 0 00101 */
146 #define IP6OPT_RTALERT_LEN	4
147 #define IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
148 #define IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
149 #define IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
150 #define IP6OPT_MINLEN		2
151 
152 #define IP6OPT_TYPE(o)		((o) & 0xC0)
153 #define IP6OPT_TYPE_SKIP	0x00
154 #define IP6OPT_TYPE_DISCARD	0x40
155 #define IP6OPT_TYPE_FORCEICMP	0x80
156 #define IP6OPT_TYPE_ICMP	0xC0
157 
158 #define IP6OPT_MUTABLE		0x20
159 
160 /* Routing header */
161 struct ip6_rthdr {
162 	u_int8_t  ip6r_nxt;	/* next header */
163 	u_int8_t  ip6r_len;	/* length in units of 8 octets */
164 	u_int8_t  ip6r_type;	/* routing type */
165 	u_int8_t  ip6r_segleft;	/* segments left */
166 	/* followed by routing type specific data */
167 } __attribute__((__packed__));
168 
169 /* Type 0 Routing header */
170 struct ip6_rthdr0 {
171 	u_int8_t  ip6r0_nxt;		/* next header */
172 	u_int8_t  ip6r0_len;		/* length in units of 8 octets */
173 	u_int8_t  ip6r0_type;		/* always zero */
174 	u_int8_t  ip6r0_segleft;	/* segments left */
175 	u_int8_t  ip6r0_reserved;	/* reserved field */
176 	u_int8_t  ip6r0_slmap[3];	/* strict/loose bit map */
177 	struct in6_addr  ip6r0_addr[1];	/* up to 23 addresses */
178 } __attribute__((__packed__));
179 
180 /* Fragment header */
181 struct ip6_frag {
182 	u_int8_t  ip6f_nxt;		/* next header */
183 	u_int8_t  ip6f_reserved;	/* reserved field */
184 	u_int16_t ip6f_offlg;		/* offset, reserved, and flag */
185 	u_int32_t ip6f_ident;		/* identification */
186 } __attribute__((__packed__));
187 
188 #if BYTE_ORDER == BIG_ENDIAN
189 #define IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
190 #define IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
191 #define IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
192 #else /* BYTE_ORDER == LITTLE_ENDIAN */
193 #define IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
194 #define IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
195 #define IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
196 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
197 
198 /*
199  * Internet implementation parameters.
200  */
201 #define IPV6_MAXHLIM	255	/* maximun hoplimit */
202 #define IPV6_DEFHLIM	64	/* default hlim */
203 #define IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
204 #define IPV6_HLIMDEC	1	/* subtracted when forwaeding */
205 
206 #define IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
207 #define IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
208 
209 #ifdef _KERNEL
210 /*
211  * IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
212  * target header (including IPv6 itself, extension headers and
213  * TCP/UDP/ICMP6 headers) are continuous. KAME requires drivers
214  * to store incoming data into one internal mbuf or one or more external
215  * mbufs(never into two or more internal mbufs). Thus, the third case is
216  * supposed to never be matched but is prepared just in case.
217  */
218 
219 #define IP6_EXTHDR_CHECK(m, off, hlen, ret)				\
220 do {									\
221     if ((m)->m_next != NULL) {						\
222 	if (((m)->m_flags & M_LOOP) &&					\
223 	    ((m)->m_len < (off) + (hlen)) &&				\
224 	    (((m) = m_pullup((m), (off) + (hlen))) == NULL)) {		\
225 		ip6stat.ip6s_exthdrtoolong++;				\
226 		return ret;						\
227 	} else if ((m)->m_flags & M_EXT) {				\
228 		if ((m)->m_len < (off) + (hlen)) {			\
229 			ip6stat.ip6s_exthdrtoolong++;			\
230 			m_freem(m);					\
231 			return ret;					\
232 		}							\
233 	} else {							\
234 		if ((m)->m_len < (off) + (hlen)) {			\
235 			ip6stat.ip6s_exthdrtoolong++;			\
236 			m_freem(m);					\
237 			return ret;					\
238 		}							\
239 	}								\
240     } else {								\
241 	if ((m)->m_len < (off) + (hlen)) {				\
242 		ip6stat.ip6s_tooshort++;				\
243 		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);	\
244 		m_freem(m);						\
245 		return ret;						\
246 	}								\
247     }									\
248 } while (/*CONSTCOND*/ 0)
249 
250 /*
251  * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
252  * "len") is located in single mbuf, on contiguous memory region.
253  * The pointer to the region will be returned to pointer variable "val",
254  * with type "typ".
255  * IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
256  * very top of mbuf.  GET0 is likely to make memory copy than GET.
257  *
258  * XXX we're now testing this, needs m_pulldown()
259  */
260 #define IP6_EXTHDR_GET(val, typ, m, off, len) \
261 do {									\
262 	struct mbuf *t;							\
263 	int tmp;							\
264 	if ((m)->m_len >= (off) + (len))				\
265 		(val) = (typ)(mtod((m), caddr_t) + (off));		\
266 	else {								\
267 		t = m_pulldown((m), (off), (len), &tmp);		\
268 		if (t) {						\
269 			if (t->m_len < tmp + (len))			\
270 				panic("m_pulldown malfunction");	\
271 			(val) = (typ)(mtod(t, caddr_t) + tmp);		\
272 		} else {						\
273 			(val) = (typ)NULL;				\
274 			(m) = NULL;					\
275 		}							\
276 	}								\
277 } while (/*CONSTCOND*/ 0)
278 
279 #define IP6_EXTHDR_GET0(val, typ, m, off, len) \
280 do {									\
281 	struct mbuf *t;							\
282 	if ((off) == 0 && (m)->m_len >= len)				\
283 		(val) = (typ)mtod((m), caddr_t);			\
284 	else {								\
285 		t = m_pulldown((m), (off), (len), NULL);		\
286 		if (t) {						\
287 			if (t->m_len < (len))				\
288 				panic("m_pulldown malfunction");	\
289 			(val) = (typ)mtod(t, caddr_t);			\
290 		} else {						\
291 			(val) = (typ)NULL;				\
292 			(m) = NULL;					\
293 		}							\
294 	}								\
295 } while (/*CONSTCOND*/ 0)
296 #endif /*_KERNEL*/
297 
298 #endif /* not _NETINET_IP6_H_ */
299