xref: /freebsd/sys/netinet/ip6.h (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
1 /*	$FreeBSD$	*/
2 /*	$KAME: ip6.h,v 1.9 2000/07/02 21:01:32 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 };
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 /* ECN bits proposed by Sally Floyd */
110 #define IP6TOS_CE		0x01	/* congestion experienced */
111 #define IP6TOS_ECT		0x02	/* ECN-capable transport */
112 
113 /*
114  * Extension Headers
115  */
116 
117 struct	ip6_ext {
118 	u_char	ip6e_nxt;
119 	u_char	ip6e_len;
120 };
121 
122 /* Hop-by-Hop options header */
123 /* XXX should we pad it to force alignment on an 8-byte boundary? */
124 struct ip6_hbh {
125 	u_int8_t ip6h_nxt;	/* next header */
126 	u_int8_t ip6h_len;	/* length in units of 8 octets */
127 	/* followed by options */
128 };
129 
130 /* Destination options header */
131 /* XXX should we pad it to force alignment on an 8-byte boundary? */
132 struct ip6_dest {
133 	u_int8_t ip6d_nxt;	/* next header */
134 	u_int8_t ip6d_len;	/* length in units of 8 octets */
135 	/* followed by options */
136 };
137 
138 /* Option types and related macros */
139 #define IP6OPT_PAD1		0x00	/* 00 0 00000 */
140 #define IP6OPT_PADN		0x01	/* 00 0 00001 */
141 #define IP6OPT_JUMBO		0xC2	/* 11 0 00010 = 194 */
142 #define IP6OPT_JUMBO_LEN	6
143 #define IP6OPT_RTALERT		0x05	/* 00 0 00101 */
144 #define IP6OPT_RTALERT_LEN	4
145 #define IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
146 #define IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
147 #define IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
148 #define IP6OPT_MINLEN		2
149 
150 #define IP6OPT_TYPE(o)		((o) & 0xC0)
151 #define IP6OPT_TYPE_SKIP	0x00
152 #define IP6OPT_TYPE_DISCARD	0x40
153 #define IP6OPT_TYPE_FORCEICMP	0x80
154 #define IP6OPT_TYPE_ICMP	0xC0
155 
156 #define IP6OPT_MUTABLE		0x20
157 
158 /* Routing header */
159 struct ip6_rthdr {
160 	u_int8_t  ip6r_nxt;	/* next header */
161 	u_int8_t  ip6r_len;	/* length in units of 8 octets */
162 	u_int8_t  ip6r_type;	/* routing type */
163 	u_int8_t  ip6r_segleft;	/* segments left */
164 	/* followed by routing type specific data */
165 };
166 
167 /* Type 0 Routing header */
168 struct ip6_rthdr0 {
169 	u_int8_t  ip6r0_nxt;		/* next header */
170 	u_int8_t  ip6r0_len;		/* length in units of 8 octets */
171 	u_int8_t  ip6r0_type;		/* always zero */
172 	u_int8_t  ip6r0_segleft;	/* segments left */
173 	u_int8_t  ip6r0_reserved;	/* reserved field */
174 	u_int8_t  ip6r0_slmap[3];	/* strict/loose bit map */
175 	struct in6_addr  ip6r0_addr[1];	/* up to 23 addresses */
176 };
177 
178 /* Fragment header */
179 struct ip6_frag {
180 	u_int8_t  ip6f_nxt;		/* next header */
181 	u_int8_t  ip6f_reserved;	/* reserved field */
182 	u_int16_t ip6f_offlg;		/* offset, reserved, and flag */
183 	u_int32_t ip6f_ident;		/* identification */
184 };
185 
186 #if BYTE_ORDER == BIG_ENDIAN
187 #define IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
188 #define IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
189 #define IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
190 #else /* BYTE_ORDER == LITTLE_ENDIAN */
191 #define IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
192 #define IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
193 #define IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
194 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
195 
196 /*
197  * Internet implementation parameters.
198  */
199 #define IPV6_MAXHLIM	255	/* maximun hoplimit */
200 #define IPV6_DEFHLIM	64	/* default hlim */
201 #define IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
202 #define IPV6_HLIMDEC	1	/* subtracted when forwaeding */
203 
204 #define IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
205 #define IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
206 
207 #ifdef _KERNEL
208 /*
209  * IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
210  * target header (including IPv6 itself, extension headers and
211  * TCP/UDP/ICMP6 headers) are continuous. KAME requires drivers
212  * to store incoming data into one internal mbuf or one or more external
213  * mbufs(never into two or more internal mbufs). Thus, the third case is
214  * supposed to never be matched but is prepared just in case.
215  */
216 
217 #define IP6_EXTHDR_CHECK(m, off, hlen, ret)				\
218 do {									\
219     if ((m)->m_next != NULL) {						\
220 	if (((m)->m_flags & M_LOOP) &&					\
221 	    ((m)->m_len < (off) + (hlen)) &&				\
222 	    (((m) = m_pullup((m), (off) + (hlen))) == NULL)) {		\
223 		ip6stat.ip6s_exthdrtoolong++;				\
224 		return ret;						\
225 	} else if ((m)->m_flags & M_EXT) {				\
226 		if ((m)->m_len < (off) + (hlen)) {			\
227 			ip6stat.ip6s_exthdrtoolong++;			\
228 			m_freem(m);					\
229 			return ret;					\
230 		}							\
231 	} else {							\
232 		if ((m)->m_len < (off) + (hlen)) {			\
233 			ip6stat.ip6s_exthdrtoolong++;			\
234 			m_freem(m);					\
235 			return ret;					\
236 		}							\
237 	}								\
238     } else {								\
239 	if ((m)->m_len < (off) + (hlen)) {				\
240 		ip6stat.ip6s_tooshort++;				\
241 		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);	\
242 		m_freem(m);						\
243 		return ret;						\
244 	}								\
245     }									\
246 } while (0)
247 
248 /*
249  * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
250  * "len") is located in single mbuf, on contiguous memory region.
251  * The pointer to the region will be returned to pointer variable "val",
252  * with type "typ".
253  * IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
254  * very top of mbuf.  GET0 is likely to make memory copy than GET.
255  *
256  * XXX we're now testing this, needs m_pulldown()
257  */
258 #define IP6_EXTHDR_GET(val, typ, m, off, len) \
259 do {									\
260 	struct mbuf *t;							\
261 	int tmp;							\
262 	if ((m)->m_len >= (off) + (len))				\
263 		(val) = (typ)(mtod((m), caddr_t) + (off));		\
264 	else {								\
265 		t = m_pulldown((m), (off), (len), &tmp);		\
266 		if (t) {						\
267 			if (t->m_len < tmp + (len))			\
268 				panic("m_pulldown malfunction");	\
269 			(val) = (typ)(mtod(t, caddr_t) + tmp);		\
270 		} else {						\
271 			(val) = (typ)NULL;				\
272 			(m) = NULL;					\
273 		}							\
274 	}								\
275 } while (0)
276 
277 #define IP6_EXTHDR_GET0(val, typ, m, off, len) \
278 do {									\
279 	struct mbuf *t;							\
280 	if ((off) == 0)							\
281 		(val) = (typ)mtod(m, caddr_t);				\
282 	else {								\
283 		t = m_pulldown((m), (off), (len), NULL);		\
284 		if (t) {						\
285 			if (t->m_len < (len))				\
286 				panic("m_pulldown malfunction");	\
287 			(val) = (typ)mtod(t, caddr_t);			\
288 		} else {						\
289 			(val) = (typ)NULL;				\
290 			(m) = NULL;					\
291 		}							\
292 	}								\
293 } while (0)
294 #endif /*_KERNEL*/
295 
296 #endif /* not _NETINET_IP6_H_ */
297