xref: /xnu-10002.61.3/bsd/netinet/ip6.h (revision 0f4c859e951fba394238ab619495c4e1d54d0f34)
1 /*
2  * Copyright (c) 2000-2019 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /*	$KAME: ip6.h,v 1.18 2001/03/29 05:34:30 itojun Exp $*/
29 
30 /*
31  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
32  * All rights reserved.
33  *
34  * Redistribution and use in source and binary forms, with or without
35  * modification, are permitted provided that the following conditions
36  * are met:
37  * 1. Redistributions of source code must retain the above copyright
38  *    notice, this list of conditions and the following disclaimer.
39  * 2. Redistributions in binary form must reproduce the above copyright
40  *    notice, this list of conditions and the following disclaimer in the
41  *    documentation and/or other materials provided with the distribution.
42  * 3. Neither the name of the project nor the names of its contributors
43  *    may be used to endorse or promote products derived from this software
44  *    without specific prior written permission.
45  *
46  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56  * SUCH DAMAGE.
57  */
58 
59 /*
60  * Copyright (c) 1982, 1986, 1993
61  *	The Regents of the University of California.  All rights reserved.
62  *
63  * Redistribution and use in source and binary forms, with or without
64  * modification, are permitted provided that the following conditions
65  * are met:
66  * 1. Redistributions of source code must retain the above copyright
67  *    notice, this list of conditions and the following disclaimer.
68  * 2. Redistributions in binary form must reproduce the above copyright
69  *    notice, this list of conditions and the following disclaimer in the
70  *    documentation and/or other materials provided with the distribution.
71  * 3. All advertising materials mentioning features or use of this software
72  *    must display the following acknowledgement:
73  *	This product includes software developed by the University of
74  *	California, Berkeley and its contributors.
75  * 4. Neither the name of the University nor the names of its contributors
76  *    may be used to endorse or promote products derived from this software
77  *    without specific prior written permission.
78  *
79  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
80  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
81  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
82  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
83  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
84  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
85  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
86  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
87  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
88  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
89  * SUCH DAMAGE.
90  *
91  *	@(#)ip.h	8.1 (Berkeley) 6/10/93
92  */
93 
94 #ifndef _NETINET_IP6_H_
95 #define _NETINET_IP6_H_
96 #ifndef DRIVERKIT
97 #include <sys/appleapiopts.h>
98 #include <sys/types.h>
99 #else
100 #include <sys/_types.h>
101 #include <machine/endian.h>
102 #endif /* DRIVERKIT */
103 #include <netinet/in.h>
104 
105 /*
106  * Definition for internet protocol version 6.
107  * RFC 2460
108  */
109 
110 struct ip6_hdr {
111 	union {
112 		struct ip6_hdrctl {
113 			u_int32_t ip6_un1_flow; /* 20 bits of flow-ID */
114 			u_int16_t ip6_un1_plen; /* payload length */
115 			u_int8_t  ip6_un1_nxt;  /* next header */
116 			u_int8_t  ip6_un1_hlim; /* hop limit */
117 		} ip6_un1;
118 		u_int8_t ip6_un2_vfc;   /* 4 bits version, top 4 bits class */
119 	} ip6_ctlun;
120 	struct in6_addr ip6_src;        /* source address */
121 	struct in6_addr ip6_dst;        /* destination address */
122 } __attribute__((__packed__));
123 
124 #define ip6_vfc         ip6_ctlun.ip6_un2_vfc
125 #define ip6_flow        ip6_ctlun.ip6_un1.ip6_un1_flow
126 #define ip6_plen        ip6_ctlun.ip6_un1.ip6_un1_plen
127 #define ip6_nxt         ip6_ctlun.ip6_un1.ip6_un1_nxt
128 #define ip6_hlim        ip6_ctlun.ip6_un1.ip6_un1_hlim
129 #define ip6_hops        ip6_ctlun.ip6_un1.ip6_un1_hlim
130 
131 #define IPV6_VERSION            0x60
132 #define IPV6_VERSION_MASK       0xf0
133 
134 #if BYTE_ORDER == BIG_ENDIAN
135 #define IPV6_FLOWINFO_MASK      0x0fffffff      /* flow info (28 bits) */
136 #define IPV6_FLOWLABEL_MASK     0x000fffff      /* flow label (20 bits) */
137 #define IPV6_FLOW_ECN_MASK      0x00300000      /* the 2 ECN bits */
138 #else
139 #if BYTE_ORDER == LITTLE_ENDIAN
140 #define IPV6_FLOWINFO_MASK      0xffffff0f      /* flow info (28 bits) */
141 #define IPV6_FLOWLABEL_MASK     0xffff0f00      /* flow label (20 bits) */
142 #define IPV6_FLOW_ECN_MASK      0x00003000      /* the 2 ECN bits */
143 #endif /* LITTLE_ENDIAN */
144 #endif
145 #if 1
146 /* ECN bits proposed by Sally Floyd */
147 #define IP6TOS_CE               0x01    /* congestion experienced */
148 #define IP6TOS_ECT              0x02    /* ECN-capable transport */
149 #endif
150 
151 /*
152  * To access the 6 bits of the DSCP value in the 32 bits ip6_flow field
153  */
154 #define IP6FLOW_DSCP_MASK       0x0fc00000
155 #define IP6FLOW_DSCP_SHIFT      22
156 
157 /*
158  * Extension Headers
159  */
160 
161 struct  ip6_ext {
162 	u_int8_t ip6e_nxt;
163 	u_int8_t ip6e_len;
164 } __attribute__((__packed__));
165 
166 /* Hop-by-Hop options header */
167 /* XXX should we pad it to force alignment on an 8-byte boundary? */
168 struct ip6_hbh {
169 	u_int8_t ip6h_nxt;      /* next header */
170 	u_int8_t ip6h_len;      /* length in units of 8 octets */
171 	/* followed by options */
172 } __attribute__((__packed__));
173 
174 /* Destination options header */
175 /* XXX should we pad it to force alignment on an 8-byte boundary? */
176 struct ip6_dest {
177 	u_int8_t ip6d_nxt;      /* next header */
178 	u_int8_t ip6d_len;      /* length in units of 8 octets */
179 	/* followed by options */
180 } __attribute__((__packed__));
181 
182 /* Option types and related macros */
183 #define IP6OPT_PAD1             0x00    /* 00 0 00000 */
184 #define IP6OPT_PADN             0x01    /* 00 0 00001 */
185 #define IP6OPT_JUMBO            0xC2    /* 11 0 00010 = 194 */
186 #define IP6OPT_NSAP_ADDR        0xC3    /* 11 0 00011 */
187 #define IP6OPT_TUNNEL_LIMIT     0x04    /* 00 0 00100 */
188 #ifndef KERNEL_PRIVATE
189 #define IP6OPT_RTALERT          0x05    /* 00 0 00101 (KAME definition) */
190 #endif
191 #define IP6OPT_ROUTER_ALERT     0x05    /* 00 0 00101 (RFC3542, recommended) */
192 
193 #define IP6OPT_RTALERT_LEN      4
194 #define IP6OPT_RTALERT_MLD      0       /* Datagram contains an MLD message */
195 #define IP6OPT_RTALERT_RSVP     1       /* Datagram contains an RSVP message */
196 #define IP6OPT_RTALERT_ACTNET   2       /* contains an Active Networks msg */
197 #define IP6OPT_MINLEN           2
198 
199 #define IP6OPT_EID              0x8a    /* 10 0 01010 */
200 
201 #define IP6OPT_TYPE(o)          ((o) & 0xC0)
202 #define IP6OPT_TYPE_SKIP        0x00
203 #define IP6OPT_TYPE_DISCARD     0x40
204 #define IP6OPT_TYPE_FORCEICMP   0x80
205 #define IP6OPT_TYPE_ICMP        0xC0
206 
207 #define IP6OPT_MUTABLE          0x20
208 
209 /* IPv6 options: common part */
210 struct ip6_opt {
211 	u_int8_t ip6o_type;
212 	u_int8_t ip6o_len;
213 } __attribute__((__packed__));
214 
215 /* Jumbo Payload Option */
216 struct ip6_opt_jumbo {
217 	u_int8_t ip6oj_type;
218 	u_int8_t ip6oj_len;
219 	u_int8_t ip6oj_jumbo_len[4];
220 } __attribute__((__packed__));
221 #define IP6OPT_JUMBO_LEN        6
222 
223 /* NSAP Address Option */
224 struct ip6_opt_nsap {
225 	u_int8_t ip6on_type;
226 	u_int8_t ip6on_len;
227 	u_int8_t ip6on_src_nsap_len;
228 	u_int8_t ip6on_dst_nsap_len;
229 	/* followed by source NSAP */
230 	/* followed by destination NSAP */
231 }__attribute__((__packed__));
232 
233 /* Tunnel Limit Option */
234 struct ip6_opt_tunnel {
235 	u_int8_t ip6ot_type;
236 	u_int8_t ip6ot_len;
237 	u_int8_t ip6ot_encap_limit;
238 }__attribute__((__packed__));
239 
240 /* Router Alert Option */
241 struct ip6_opt_router {
242 	u_int8_t ip6or_type;
243 	u_int8_t ip6or_len;
244 	u_int8_t ip6or_value[2];
245 }__attribute__((__packed__));
246 /* Router alert values (in network byte order) */
247 #if BYTE_ORDER == BIG_ENDIAN
248 #define IP6_ALERT_MLD   0x0000
249 #define IP6_ALERT_RSVP  0x0001
250 #define IP6_ALERT_AN    0x0002
251 #else
252 #if BYTE_ORDER == LITTLE_ENDIAN
253 #define IP6_ALERT_MLD   0x0000
254 #define IP6_ALERT_RSVP  0x0100
255 #define IP6_ALERT_AN    0x0200
256 #endif /* LITTLE_ENDIAN */
257 #endif
258 
259 /* Routing header */
260 struct ip6_rthdr {
261 	u_int8_t  ip6r_nxt;     /* next header */
262 	u_int8_t  ip6r_len;     /* length in units of 8 octets */
263 	u_int8_t  ip6r_type;    /* routing type */
264 	u_int8_t  ip6r_segleft; /* segments left */
265 	/* followed by routing type specific data */
266 } __attribute__((__packed__));
267 
268 /* Type 0 Routing header, deprecated by RFC 5095. */
269 struct ip6_rthdr0 {
270 	u_int8_t  ip6r0_nxt;            /* next header */
271 	u_int8_t  ip6r0_len;            /* length in units of 8 octets */
272 	u_int8_t  ip6r0_type;           /* always zero */
273 	u_int8_t  ip6r0_segleft;        /* segments left */
274 	u_int32_t  ip6r0_reserved;      /* reserved field */
275 	/* followed by up to 127 struct in6_addr */
276 } __attribute__((__packed__));
277 
278 /* Fragment header */
279 struct ip6_frag {
280 	u_int8_t  ip6f_nxt;             /* next header */
281 	u_int8_t  ip6f_reserved;        /* reserved field */
282 	u_int16_t ip6f_offlg;           /* offset, reserved, and flag */
283 	u_int32_t ip6f_ident;           /* identification */
284 } __attribute__((__packed__));
285 
286 #if BYTE_ORDER == BIG_ENDIAN
287 #define IP6F_OFF_MASK           0xfff8  /* mask out offset from _offlg */
288 #define IP6F_RESERVED_MASK      0x0006  /* reserved bits in ip6f_offlg */
289 #define IP6F_MORE_FRAG          0x0001  /* more-fragments flag */
290 #else /* BYTE_ORDER == LITTLE_ENDIAN */
291 #define IP6F_OFF_MASK           0xf8ff  /* mask out offset from _offlg */
292 #define IP6F_RESERVED_MASK      0x0600  /* reserved bits in ip6f_offlg */
293 #define IP6F_MORE_FRAG          0x0100  /* more-fragments flag */
294 #endif /* BYTE_ORDER == LITTLE_ENDIAN */
295 
296 /*
297  * Internet implementation parameters.
298  */
299 #define IPV6_MAXHLIM    255     /* maximum hoplimit */
300 #define IPV6_DEFHLIM    64      /* default hlim */
301 #define IPV6_FRAGTTL    60      /* ttl for fragment packets (seconds) */
302 #define IPV6_HLIMDEC    1       /* subtracted when forwarding */
303 
304 #define IPV6_MMTU       1280    /* minimal MTU and reassembly. 1024 + 256 */
305 #define IPV6_MAXPACKET  65535   /* ip6 max packet size without Jumbo payload*/
306 #define IPV6_MAXOPTHDR  2048    /* max option header size, 256 64-bit words */
307 
308 #ifdef BSD_KERNEL_PRIVATE
309 /*
310  * IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
311  * target header (including IPv6 itself, extension headers and
312  * TCP/UDP/ICMP6 headers) are continuous. KAME requires drivers
313  * to store incoming data into one internal mbuf or one or more external
314  * mbufs(never into two or more internal mbufs). Thus, the third case is
315  * supposed to never be matched but is prepared just in case.
316  */
317 
318 #define IP6_EXTHDR_CHECK(m, off, hlen, action)                          \
319 do {                                                                    \
320     if ((m)->m_next != NULL) {                                          \
321 	if (((m)->m_flags & M_LOOP) &&                                  \
322 	    ((m)->m_len < (off) + (hlen)) &&                            \
323 	    (((m) = m_pullup((m), (off) + (hlen))) == NULL)) {          \
324 	        ip6stat.ip6s_exthdrtoolong++;                           \
325 	        action;                                                 \
326 	} else if ((m)->m_flags & M_EXT) {                              \
327 	        if ((m)->m_len < (off) + (hlen)) {                      \
328 	                ip6stat.ip6s_exthdrtoolong++;                   \
329 	                m_freem(m);                                     \
330 	                (m) = NULL;                                     \
331 	                action;                                         \
332 	        }                                                       \
333 	} else {                                                        \
334 	        if ((m)->m_len < (off) + (hlen)) {                      \
335 	                ip6stat.ip6s_exthdrtoolong++;                   \
336 	                m_freem(m);                                     \
337 	                (m) = NULL;                                     \
338 	                action;                                         \
339 	        }                                                       \
340 	}                                                               \
341     } else {                                                            \
342 	if ((m)->m_len < (off) + (hlen)) {                              \
343 	        ip6stat.ip6s_tooshort++;                                \
344 	        in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);   \
345 	        m_freem(m);                                             \
346 	        (m) = NULL;                                             \
347 	        action;                                                 \
348 	}                                                               \
349     }                                                                   \
350 } while (0)
351 
352 /*
353  * IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
354  * "len") is located in single mbuf, on contiguous memory region.
355  * The pointer to the region will be returned to pointer variable "val",
356  * with type "typ".
357  * IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
358  * very top of mbuf.  GET0 is likely to make memory copy than GET.
359  */
360 #define IP6_EXTHDR_GET(val, typ, m, off, len)                           \
361 	M_STRUCT_GET(val, typ, m, off, len)
362 
363 #define IP6_EXTHDR_GET0(val, typ, m, off, len)                          \
364 	M_STRUCT_GET0(val, typ, m, off, len)
365 
366 #endif /* BSD_KERNEL_PRIVATE */
367 #endif /* !_NETINET_IP6_H_ */
368