xref: /freebsd/sys/netinet/ip6.h (revision 3193579b66fd7067f898dbc54bdea81a0e6f9bd0)
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  * 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 } __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 } __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 } __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 } __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_NSAP_ADDR	0xC3	/* 11 0 00011 */
145 #define IP6OPT_TUNNEL_LIMIT	0x04	/* 00 0 00100 */
146 #ifndef _KERNEL
147 #define IP6OPT_RTALERT		0x05	/* 00 0 00101 (KAME definition) */
148 #endif
149 #define IP6OPT_ROUTER_ALERT	0x05	/* 00 0 00101 (2292bis, recommended) */
150 
151 #define IP6OPT_RTALERT_LEN	4
152 #define IP6OPT_RTALERT_MLD	0	/* Datagram contains an MLD message */
153 #define IP6OPT_RTALERT_RSVP	1	/* Datagram contains an RSVP message */
154 #define IP6OPT_RTALERT_ACTNET	2 	/* contains an Active Networks msg */
155 #define IP6OPT_MINLEN		2
156 
157 #define IP6OPT_EID		0x8a	/* 10 0 01010 */
158 
159 #define IP6OPT_TYPE(o)		((o) & 0xC0)
160 #define IP6OPT_TYPE_SKIP	0x00
161 #define IP6OPT_TYPE_DISCARD	0x40
162 #define IP6OPT_TYPE_FORCEICMP	0x80
163 #define IP6OPT_TYPE_ICMP	0xC0
164 
165 #define IP6OPT_MUTABLE		0x20
166 
167 #define IP6OPT_JUMBO_LEN	6
168 
169 /* Routing header */
170 struct ip6_rthdr {
171 	u_int8_t  ip6r_nxt;	/* next header */
172 	u_int8_t  ip6r_len;	/* length in units of 8 octets */
173 	u_int8_t  ip6r_type;	/* routing type */
174 	u_int8_t  ip6r_segleft;	/* segments left */
175 	/* followed by routing type specific data */
176 } __packed;
177 
178 /* Type 0 Routing header */
179 struct ip6_rthdr0 {
180 	u_int8_t  ip6r0_nxt;		/* next header */
181 	u_int8_t  ip6r0_len;		/* length in units of 8 octets */
182 	u_int8_t  ip6r0_type;		/* always zero */
183 	u_int8_t  ip6r0_segleft;	/* segments left */
184 	u_int32_t  ip6r0_reserved;	/* reserved field */
185 	/* followed by up to 127 struct in6_addr */
186 } __packed;
187 
188 /* Fragment header */
189 struct ip6_frag {
190 	u_int8_t  ip6f_nxt;		/* next header */
191 	u_int8_t  ip6f_reserved;	/* reserved field */
192 	u_int16_t ip6f_offlg;		/* offset, reserved, and flag */
193 	u_int32_t ip6f_ident;		/* identification */
194 } __packed;
195 
196 #if BYTE_ORDER == BIG_ENDIAN
197 #define IP6F_OFF_MASK		0xfff8	/* mask out offset from _offlg */
198 #define IP6F_RESERVED_MASK	0x0006	/* reserved bits in ip6f_offlg */
199 #define IP6F_MORE_FRAG		0x0001	/* more-fragments flag */
200 #else /* BYTE_ORDER == LITTLE_ENDIAN */
201 #define IP6F_OFF_MASK		0xf8ff	/* mask out offset from _offlg */
202 #define IP6F_RESERVED_MASK	0x0600	/* reserved bits in ip6f_offlg */
203 #define IP6F_MORE_FRAG		0x0100	/* more-fragments flag */
204 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
205 
206 /*
207  * Internet implementation parameters.
208  */
209 #define IPV6_MAXHLIM	255	/* maximun hoplimit */
210 #define IPV6_DEFHLIM	64	/* default hlim */
211 #define IPV6_FRAGTTL	120	/* ttl for fragment packets, in slowtimo tick */
212 #define IPV6_HLIMDEC	1	/* subtracted when forwaeding */
213 
214 #define IPV6_MMTU	1280	/* minimal MTU and reassembly. 1024 + 256 */
215 #define IPV6_MAXPACKET	65535	/* ip6 max packet size without Jumbo payload*/
216 
217 #ifdef _KERNEL
218 /*
219  * IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
220  * target header (including IPv6 itself, extension headers and
221  * TCP/UDP/ICMP6 headers) are continuous. KAME requires drivers
222  * to store incoming data into one internal mbuf or one or more external
223  * mbufs(never into two or more internal mbufs). Thus, the third case is
224  * supposed to never be matched but is prepared just in case.
225  */
226 
227 #define IP6_EXTHDR_CHECK(m, off, hlen, ret)				\
228 do {									\
229     if ((m)->m_next != NULL) {						\
230 	if (((m)->m_flags & M_LOOP) &&					\
231 	    ((m)->m_len < (off) + (hlen)) &&				\
232 	    (((m) = m_pullup((m), (off) + (hlen))) == NULL)) {		\
233 		ip6stat.ip6s_exthdrtoolong++;				\
234 		return ret;						\
235 	} else if ((m)->m_flags & M_EXT) {				\
236 		if ((m)->m_len < (off) + (hlen)) {			\
237 			ip6stat.ip6s_exthdrtoolong++;			\
238 			m_freem(m);					\
239 			return ret;					\
240 		}							\
241 	} else {							\
242 		if ((m)->m_len < (off) + (hlen)) {			\
243 			ip6stat.ip6s_exthdrtoolong++;			\
244 			m_freem(m);					\
245 			return ret;					\
246 		}							\
247 	}								\
248     } else {								\
249 	if ((m)->m_len < (off) + (hlen)) {				\
250 		ip6stat.ip6s_tooshort++;				\
251 		in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);	\
252 		m_freem(m);						\
253 		return ret;						\
254 	}								\
255     }									\
256 } while (/*CONSTCOND*/ 0)
257 
258 /*
259  * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
260  * "len") is located in single mbuf, on contiguous memory region.
261  * The pointer to the region will be returned to pointer variable "val",
262  * with type "typ".
263  * IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
264  * very top of mbuf.  GET0 is likely to make memory copy than GET.
265  *
266  * XXX we're now testing this, needs m_pulldown()
267  */
268 #define IP6_EXTHDR_GET(val, typ, m, off, len) \
269 do {									\
270 	struct mbuf *t;							\
271 	int tmp;							\
272 	if ((m)->m_len >= (off) + (len))				\
273 		(val) = (typ)(mtod((m), caddr_t) + (off));		\
274 	else {								\
275 		t = m_pulldown((m), (off), (len), &tmp);		\
276 		if (t) {						\
277 			if (t->m_len < tmp + (len))			\
278 				panic("m_pulldown malfunction");	\
279 			(val) = (typ)(mtod(t, caddr_t) + tmp);		\
280 		} else {						\
281 			(val) = (typ)NULL;				\
282 			(m) = NULL;					\
283 		}							\
284 	}								\
285 } while (/*CONSTCOND*/ 0)
286 
287 #define IP6_EXTHDR_GET0(val, typ, m, off, len) \
288 do {									\
289 	struct mbuf *t;							\
290 	if ((off) == 0)							\
291 		(val) = (typ)mtod(m, caddr_t);				\
292 	else {								\
293 		t = m_pulldown((m), (off), (len), NULL);		\
294 		if (t) {						\
295 			if (t->m_len < (len))				\
296 				panic("m_pulldown malfunction");	\
297 			(val) = (typ)mtod(t, caddr_t);			\
298 		} else {						\
299 			(val) = (typ)NULL;				\
300 			(m) = NULL;					\
301 		}							\
302 	}								\
303 } while (/*CONSTCOND*/ 0)
304 #endif /*_KERNEL*/
305 
306 #endif /* not _NETINET_IP6_H_ */
307