xref: /freebsd/sys/netinet6/ip6.h (revision 5129159789cc9d7bc514e4546b88e3427695002d)
1 /*
2  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the project nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 /*
33  * Copyright (c) 1982, 1986, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. All advertising materials mentioning features or use of this software
45  *    must display the following acknowledgement:
46  *	This product includes software developed by the University of
47  *	California, Berkeley and its contributors.
48  * 4. Neither the name of the University nor the names of its contributors
49  *    may be used to endorse or promote products derived from this software
50  *    without specific prior written permission.
51  *
52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62  * SUCH DAMAGE.
63  *
64  *	@(#)ip.h	8.1 (Berkeley) 6/10/93
65  */
66 
67 #ifndef _NETINET6_IPV6_H_
68 #define _NETINET6_IPV6_H_
69 
70 /*
71  * Definition for internet protocol version 6.
72  * RFC 2460
73  */
74 
75 struct ip6_hdr {
76 	union {
77 		struct ip6_hdrctl {
78 			u_int32_t	ip6_un1_flow; /* 20 bits of flow-ID */
79 			u_int16_t	ip6_un1_plen;	/* payload length */
80 			u_int8_t	ip6_un1_nxt;	/* next header */
81 			u_int8_t	ip6_un1_hlim;	/* hop limit */
82 		} ip6_un1;
83 		u_int8_t	ip6_un2_vfc; /* 4 bits version, 4 bits class */
84 	} ip6_ctlun;
85 	struct	in6_addr ip6_src;	/* source address */
86 	struct	in6_addr ip6_dst;	/* destination address */
87 };
88 
89 #define	ip6_vfc		ip6_ctlun.ip6_un2_vfc
90 #define	ip6_flow	ip6_ctlun.ip6_un1.ip6_un1_flow
91 #define	ip6_plen	ip6_ctlun.ip6_un1.ip6_un1_plen
92 #define	ip6_nxt		ip6_ctlun.ip6_un1.ip6_un1_nxt
93 #define	ip6_hlim	ip6_ctlun.ip6_un1.ip6_un1_hlim
94 #define	ip6_hops	ip6_ctlun.ip6_un1.ip6_un1_hlim
95 
96 #define	IPV6_VERSION		0x60
97 #define	IPV6_VERSION_MASK	0xf0
98 
99 #if BYTE_ORDER == BIG_ENDIAN
100 #define	IPV6_FLOWINFO_MASK	0x0fffffff	/* flow info (28 bits) */
101 #define	IPV6_FLOWLABEL_MASK	0x000fffff	/* flow label (20 bits) */
102 #endif /* BIG_ENDIAN */
103 #if BYTE_ORDER == LITTLE_ENDIAN
104 #define	IPV6_FLOWINFO_MASK	0xffffff0f	/* flow info (28 bits) */
105 #define	IPV6_FLOWLABEL_MASK	0xffff0f00	/* flow label (20 bits) */
106 #endif /* LITTLE_ENDIAN */
107 /* ECN bits proposed by Sally Floyd */
108 #define	IP6TOS_CE		0x01	/* congestion experienced */
109 #define	IP6TOS_ECT		0x02	/* ECN-capable transport */
110 
111 /*
112  * Extension Headers
113  */
114 
115 struct	ip6_ext {
116 	u_char	ip6e_nxt;
117 	u_char	ip6e_len;
118 };
119 
120 /* Hop-by-Hop options header */
121 /* XXX should we pad it to force alignment on an 8-byte boundary? */
122 struct ip6_hbh {
123 	u_int8_t	ip6h_nxt;	/* next header */
124 	u_int8_t	ip6h_len;	/* length in units of 8 octets */
125 	/* followed by options */
126 };
127 
128 /* Destination options header */
129 /* XXX should we pad it to force alignment on an 8-byte boundary? */
130 struct ip6_dest {
131 	u_int8_t	ip6d_nxt;	/* next header */
132 	u_int8_t	ip6d_len;	/* length in units of 8 octets */
133 	/* followed by options */
134 };
135 
136 /* Option types and related macros */
137 #define	IP6OPT_PAD1		0x00	/* 00 0 00000 */
138 #define	IP6OPT_PADN		0x01	/* 00 0 00001 */
139 #define	IP6OPT_JUMBO		0xC2	/* 11 0 00010 = 194 */
140 #define	IP6OPT_JUMBO_LEN	6
141 #define	IP6OPT_RTALERT		0x05	/* 00 0 00101 */
142 #define	IP6OPT_RTALERT_LEN	4
143 #define	IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
144 #define	IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
145 #define	IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
146 #define	IP6OPT_MINLEN		2
147 
148 #define	IP6OPT_TYPE(o)		((o) & 0xC0)
149 #define	IP6OPT_TYPE_SKIP	0x00
150 #define	IP6OPT_TYPE_DISCARD	0x40
151 #define	IP6OPT_TYPE_FORCEICMP	0x80
152 #define	IP6OPT_TYPE_ICMP	0xC0
153 
154 #define	IP6OPT_MUTABLE		0x20
155 
156 /* Routing header */
157 struct ip6_rthdr {
158 	u_int8_t	ip6r_nxt;	/* next header */
159 	u_int8_t	ip6r_len;	/* length in units of 8 octets */
160 	u_int8_t	ip6r_type;	/* routing type */
161 	u_int8_t	ip6r_segleft;	/* segments left */
162 	/* followed by routing type specific data */
163 };
164 
165 /* Type 0 Routing header */
166 struct ip6_rthdr0 {
167 	u_int8_t	ip6r0_nxt;		/* next header */
168 	u_int8_t	ip6r0_len;		/* length in units of 8 octets */
169 	u_int8_t	ip6r0_type;		/* always zero */
170 	u_int8_t	ip6r0_segleft;	/* segments left */
171 	u_int8_t	ip6r0_reserved;	/* reserved field */
172 	u_int8_t	ip6r0_slmap[3];	/* strict/loose bit map */
173 	struct	in6_addr  ip6r0_addr[1];	/* up to 23 addresses */
174 };
175 
176 /* Fragment header */
177 struct ip6_frag {
178 	u_int8_t	ip6f_nxt;		/* next header */
179 	u_int8_t	ip6f_reserved;	/* reserved field */
180 	u_int16_t	ip6f_offlg;		/* offset, reserved, and flag */
181 	u_int32_t	ip6f_ident;		/* identification */
182 };
183 
184 #if BYTE_ORDER == BIG_ENDIAN
185 #define	IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
186 #define	IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
187 #define	IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
188 #else /* BYTE_ORDER == LITTLE_ENDIAN */
189 #define	IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
190 #define	IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
191 #define	IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
192 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
193 
194 /*
195  * Internet implementation parameters.
196  */
197 #define	IPV6_MAXHLIM	255	/* maximun hoplimit */
198 #define	IPV6_DEFHLIM	64	/* default hlim */
199 #define	IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
200 #define	IPV6_HLIMDEC	1	/* subtracted when forwaeding */
201 
202 #define	IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
203 #define	IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
204 
205 /*
206  * IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
207  * target header (including IPv6 itself, extension headers and
208  * TCP/UDP/ICMP6 headers) are continuous. KAME requires drivers
209  * to store incoming data into one internal mbuf or one or more external
210  * mbufs(never into two or more internal mbufs). Thus, the third case is
211  * supposed to never be matched but is prepared just in case.
212  */
213 
214 #define	IP6_EXTHDR_CHECK(m, off, hlen, ret)				\
215 do {									\
216     if ((m)->m_next != NULL) {						\
217 	if (((m)->m_flags & M_LOOP) &&					\
218 	    ((m)->m_len < (off) + (hlen)) &&				\
219 	    (((m) = m_pullup((m), (off) + (hlen))) == NULL)) {		\
220 		ip6stat.ip6s_exthdrtoolong++;				\
221 		return ret;						\
222 	} else if ((m)->m_flags & M_EXT) {				\
223 		if ((m)->m_len < (off) + (hlen)) {			\
224 			ip6stat.ip6s_exthdrtoolong++;			\
225 			m_freem(m);					\
226 			return ret;					\
227 		}							\
228 	} else {							\
229 		if ((m)->m_len < (off) + (hlen)) {			\
230 			ip6stat.ip6s_exthdrtoolong++;			\
231 			m_freem(m);					\
232 			return ret;					\
233 		}							\
234 	}								\
235     } else {								\
236 	if ((m)->m_len < (off) + (hlen)) {				\
237 		ip6stat.ip6s_tooshort++;				\
238 		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);	\
239 		m_freem(m);						\
240 		return ret;						\
241 	}								\
242     }									\
243 } while (0)
244 
245 #endif /* not _NETINET_IPV6_H_ */
246