xref: /freebsd/sys/netinet/ip6.h (revision 74bf4e164ba5851606a27d4feff27717452583e5)
1 /*	$FreeBSD$	*/
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 
72 struct 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 #if 1
106 /* ECN bits proposed by Sally Floyd */
107 #define IP6TOS_CE		0x01	/* congestion experienced */
108 #define IP6TOS_ECT		0x02	/* ECN-capable transport */
109 #endif
110 
111 /*
112  * Extension Headers
113  */
114 
115 struct	ip6_ext {
116 	u_int8_t ip6e_nxt;
117 	u_int8_t ip6e_len;
118 } __packed;
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 } __packed;
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 } __packed;
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_NSAP_ADDR	0xC3	/* 11 0 00011 */
141 #define IP6OPT_TUNNEL_LIMIT	0x04	/* 00 0 00100 */
142 #ifndef _KERNEL
143 #define IP6OPT_RTALERT		0x05	/* 00 0 00101 (KAME definition) */
144 #endif
145 #define IP6OPT_ROUTER_ALERT	0x05	/* 00 0 00101 (2292bis, recommended) */
146 
147 #define IP6OPT_RTALERT_LEN	4
148 #define IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
149 #define IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
150 #define IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
151 #define IP6OPT_MINLEN		2
152 
153 #define IP6OPT_EID		0x8a	/* 10 0 01010 */
154 
155 #define IP6OPT_TYPE(o)		((o) & 0xC0)
156 #define IP6OPT_TYPE_SKIP	0x00
157 #define IP6OPT_TYPE_DISCARD	0x40
158 #define IP6OPT_TYPE_FORCEICMP	0x80
159 #define IP6OPT_TYPE_ICMP	0xC0
160 
161 #define IP6OPT_MUTABLE		0x20
162 
163 #define IP6OPT_JUMBO_LEN	6
164 
165 /* Routing header */
166 struct ip6_rthdr {
167 	u_int8_t  ip6r_nxt;	/* next header */
168 	u_int8_t  ip6r_len;	/* length in units of 8 octets */
169 	u_int8_t  ip6r_type;	/* routing type */
170 	u_int8_t  ip6r_segleft;	/* segments left */
171 	/* followed by routing type specific data */
172 } __packed;
173 
174 /* Type 0 Routing header */
175 struct ip6_rthdr0 {
176 	u_int8_t  ip6r0_nxt;		/* next header */
177 	u_int8_t  ip6r0_len;		/* length in units of 8 octets */
178 	u_int8_t  ip6r0_type;		/* always zero */
179 	u_int8_t  ip6r0_segleft;	/* segments left */
180 	u_int32_t  ip6r0_reserved;	/* reserved field */
181 	/* followed by up to 127 struct in6_addr */
182 } __packed;
183 
184 /* Fragment header */
185 struct ip6_frag {
186 	u_int8_t  ip6f_nxt;		/* next header */
187 	u_int8_t  ip6f_reserved;	/* reserved field */
188 	u_int16_t ip6f_offlg;		/* offset, reserved, and flag */
189 	u_int32_t ip6f_ident;		/* identification */
190 } __packed;
191 
192 #if BYTE_ORDER == BIG_ENDIAN
193 #define IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
194 #define IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
195 #define IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
196 #else /* BYTE_ORDER == LITTLE_ENDIAN */
197 #define IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
198 #define IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
199 #define IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
200 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
201 
202 /*
203  * Internet implementation parameters.
204  */
205 #define IPV6_MAXHLIM	255	/* maximun hoplimit */
206 #define IPV6_DEFHLIM	64	/* default hlim */
207 #define IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
208 #define IPV6_HLIMDEC	1	/* subtracted when forwaeding */
209 
210 #define IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
211 #define IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
212 #define IPV6_MAXOPTHDR	2048	/* max option header size, 256 64-bit words */
213 
214 #ifdef _KERNEL
215 /*
216  * IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
217  * target header (including IPv6 itself, extension headers and
218  * TCP/UDP/ICMP6 headers) are continuous. KAME requires drivers
219  * to store incoming data into one internal mbuf or one or more external
220  * mbufs(never into two or more internal mbufs). Thus, the third case is
221  * supposed to never be matched but is prepared just in case.
222  */
223 
224 #define IP6_EXTHDR_CHECK(m, off, hlen, ret)				\
225 do {									\
226     if ((m)->m_next != NULL) {						\
227 	if (((m)->m_flags & M_LOOP) &&					\
228 	    ((m)->m_len < (off) + (hlen)) &&				\
229 	    (((m) = m_pullup((m), (off) + (hlen))) == NULL)) {		\
230 		ip6stat.ip6s_exthdrtoolong++;				\
231 		return ret;						\
232 	} else if ((m)->m_flags & M_EXT) {				\
233 		if ((m)->m_len < (off) + (hlen)) {			\
234 			ip6stat.ip6s_exthdrtoolong++;			\
235 			m_freem(m);					\
236 			return ret;					\
237 		}							\
238 	} else {							\
239 		if ((m)->m_len < (off) + (hlen)) {			\
240 			ip6stat.ip6s_exthdrtoolong++;			\
241 			m_freem(m);					\
242 			return ret;					\
243 		}							\
244 	}								\
245     } else {								\
246 	if ((m)->m_len < (off) + (hlen)) {				\
247 		ip6stat.ip6s_tooshort++;				\
248 		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);	\
249 		m_freem(m);						\
250 		return ret;						\
251 	}								\
252     }									\
253 } while (/*CONSTCOND*/ 0)
254 
255 /*
256  * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
257  * "len") is located in single mbuf, on contiguous memory region.
258  * The pointer to the region will be returned to pointer variable "val",
259  * with type "typ".
260  * IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
261  * very top of mbuf.  GET0 is likely to make memory copy than GET.
262  *
263  * XXX we're now testing this, needs m_pulldown()
264  */
265 #define IP6_EXTHDR_GET(val, typ, m, off, len) \
266 do {									\
267 	struct mbuf *t;							\
268 	int tmp;							\
269 	if ((m)->m_len >= (off) + (len))				\
270 		(val) = (typ)(mtod((m), caddr_t) + (off));		\
271 	else {								\
272 		t = m_pulldown((m), (off), (len), &tmp);		\
273 		if (t) {						\
274 			if (t->m_len < tmp + (len))			\
275 				panic("m_pulldown malfunction");	\
276 			(val) = (typ)(mtod(t, caddr_t) + tmp);		\
277 		} else {						\
278 			(val) = (typ)NULL;				\
279 			(m) = NULL;					\
280 		}							\
281 	}								\
282 } while (/*CONSTCOND*/ 0)
283 
284 #define IP6_EXTHDR_GET0(val, typ, m, off, len) \
285 do {									\
286 	struct mbuf *t;							\
287 	if ((off) == 0)							\
288 		(val) = (typ)mtod(m, caddr_t);				\
289 	else {								\
290 		t = m_pulldown((m), (off), (len), NULL);		\
291 		if (t) {						\
292 			if (t->m_len < (len))				\
293 				panic("m_pulldown malfunction");	\
294 			(val) = (typ)mtod(t, caddr_t);			\
295 		} else {						\
296 			(val) = (typ)NULL;				\
297 			(m) = NULL;					\
298 		}							\
299 	}								\
300 } while (/*CONSTCOND*/ 0)
301 #endif /*_KERNEL*/
302 
303 #endif /* not _NETINET_IP6_H_ */
304