1/* Copyright (C) 1991-1997, 2001, 2003, 2006 Free Software Foundation, Inc.
2   This file is part of the GNU C Library.
3
4   The GNU C Library is free software; you can redistribute it and/or
5   modify it under the terms of the GNU Lesser General Public
6   License as published by the Free Software Foundation; either
7   version 2.1 of the License, or (at your option) any later version.
8
9   The GNU C Library is distributed in the hope that it will be useful,
10   but WITHOUT ANY WARRANTY; without even the implied warranty of
11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12   Lesser General Public License for more details.
13
14   You should have received a copy of the GNU Lesser General Public
15   License along with the GNU C Library; if not, write to the Free
16   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
17   02111-1307 USA.  */
18
19#ifndef _NETINET_IP6_H
20#define _NETINET_IP6_H 1
21
22#include <inttypes.h>
23#include <netinet/in.h>
24
25struct ip6_hdr
26  {
27    union
28      {
29	struct ip6_hdrctl
30	  {
31	    uint32_t ip6_un1_flow;   /* 4 bits version, 8 bits TC,
32					20 bits flow-ID */
33	    uint16_t ip6_un1_plen;   /* payload length */
34	    uint8_t  ip6_un1_nxt;    /* next header */
35	    uint8_t  ip6_un1_hlim;   /* hop limit */
36	  } ip6_un1;
37	uint8_t ip6_un2_vfc;       /* 4 bits version, top 4 bits tclass */
38      } ip6_ctlun;
39    struct in6_addr ip6_src;      /* source address */
40    struct in6_addr ip6_dst;      /* destination address */
41  };
42
43#define ip6_vfc   ip6_ctlun.ip6_un2_vfc
44#define ip6_flow  ip6_ctlun.ip6_un1.ip6_un1_flow
45#define ip6_plen  ip6_ctlun.ip6_un1.ip6_un1_plen
46#define ip6_nxt   ip6_ctlun.ip6_un1.ip6_un1_nxt
47#define ip6_hlim  ip6_ctlun.ip6_un1.ip6_un1_hlim
48#define ip6_hops  ip6_ctlun.ip6_un1.ip6_un1_hlim
49
50/* Generic extension header.  */
51struct ip6_ext
52  {
53    uint8_t  ip6e_nxt;		/* next header.  */
54    uint8_t  ip6e_len;		/* length in units of 8 octets.  */
55  };
56
57/* Hop-by-Hop options header.  */
58struct ip6_hbh
59  {
60    uint8_t  ip6h_nxt;		/* next header.  */
61    uint8_t  ip6h_len;		/* length in units of 8 octets.  */
62    /* followed by options */
63  };
64
65/* Destination options header */
66struct ip6_dest
67  {
68    uint8_t  ip6d_nxt;		/* next header */
69    uint8_t  ip6d_len;		/* length in units of 8 octets */
70    /* followed by options */
71  };
72
73/* Routing header */
74struct ip6_rthdr
75  {
76    uint8_t  ip6r_nxt;		/* next header */
77    uint8_t  ip6r_len;		/* length in units of 8 octets */
78    uint8_t  ip6r_type;		/* routing type */
79    uint8_t  ip6r_segleft;	/* segments left */
80    /* followed by routing type specific data */
81  };
82
83/* Type 0 Routing header */
84struct ip6_rthdr0
85  {
86    uint8_t  ip6r0_nxt;		/* next header */
87    uint8_t  ip6r0_len;		/* length in units of 8 octets */
88    uint8_t  ip6r0_type;	/* always zero */
89    uint8_t  ip6r0_segleft;	/* segments left */
90    uint8_t  ip6r0_reserved;	/* reserved field */
91    uint8_t  ip6r0_slmap[3];	/* strict/loose bit map */
92    /* followed by up to 127 struct in6_addr */
93    struct in6_addr ip6r0_addr[0];
94  };
95
96/* Fragment header */
97struct ip6_frag
98  {
99    uint8_t   ip6f_nxt;		/* next header */
100    uint8_t   ip6f_reserved;	/* reserved field */
101    uint16_t  ip6f_offlg;	/* offset, reserved, and flag */
102    uint32_t  ip6f_ident;	/* identification */
103  };
104
105#if BYTE_ORDER == BIG_ENDIAN
106# define IP6F_OFF_MASK       0xfff8  /* mask out offset from _offlg */
107# define IP6F_RESERVED_MASK  0x0006  /* reserved bits in ip6f_offlg */
108# define IP6F_MORE_FRAG      0x0001  /* more-fragments flag */
109#else   /* BYTE_ORDER == LITTLE_ENDIAN */
110# define IP6F_OFF_MASK       0xf8ff  /* mask out offset from _offlg */
111# define IP6F_RESERVED_MASK  0x0600  /* reserved bits in ip6f_offlg */
112# define IP6F_MORE_FRAG      0x0100  /* more-fragments flag */
113#endif
114
115/* IPv6 options */
116struct ip6_opt
117  {
118    uint8_t  ip6o_type;
119    uint8_t  ip6o_len;
120  };
121
122/* The high-order 3 bits of the option type define the behavior
123 * when processing an unknown option and whether or not the option
124 * content changes in flight.
125 */
126#define IP6OPT_TYPE(o)		((o) & 0xc0)
127#define IP6OPT_TYPE_SKIP	0x00
128#define IP6OPT_TYPE_DISCARD	0x40
129#define IP6OPT_TYPE_FORCEICMP	0x80
130#define IP6OPT_TYPE_ICMP	0xc0
131#define IP6OPT_TYPE_MUTABLE	0x20
132
133/* Special option types for padding.  */
134#define IP6OPT_PAD1	0
135#define IP6OPT_PADN	1
136
137#define IP6OPT_JUMBO		0xc2
138#define IP6OPT_NSAP_ADDR	0xc3
139#define IP6OPT_TUNNEL_LIMIT	0x04
140#define IP6OPT_ROUTER_ALERT	0x05
141
142/* Jumbo Payload Option */
143struct ip6_opt_jumbo
144  {
145    uint8_t  ip6oj_type;
146    uint8_t  ip6oj_len;
147    uint8_t  ip6oj_jumbo_len[4];
148  };
149#define IP6OPT_JUMBO_LEN	6
150
151/* NSAP Address Option */
152struct ip6_opt_nsap
153  {
154    uint8_t  ip6on_type;
155    uint8_t  ip6on_len;
156    uint8_t  ip6on_src_nsap_len;
157    uint8_t  ip6on_dst_nsap_len;
158      /* followed by source NSAP */
159      /* followed by destination NSAP */
160  };
161
162/* Tunnel Limit Option */
163struct ip6_opt_tunnel
164  {
165    uint8_t  ip6ot_type;
166    uint8_t  ip6ot_len;
167    uint8_t  ip6ot_encap_limit;
168  };
169
170/* Router Alert Option */
171struct ip6_opt_router
172  {
173    uint8_t  ip6or_type;
174    uint8_t  ip6or_len;
175    uint8_t  ip6or_value[2];
176  };
177
178/* Router alert values (in network byte order) */
179#if BYTE_ORDER == BIG_ENDIAN
180# define IP6_ALERT_MLD	0x0000
181# define IP6_ALERT_RSVP	0x0001
182# define IP6_ALERT_AN	0x0002
183#else /* BYTE_ORDER == LITTLE_ENDING */
184# define IP6_ALERT_MLD	0x0000
185# define IP6_ALERT_RSVP	0x0100
186# define IP6_ALERT_AN	0x0200
187#endif
188
189#endif /* netinet/ip6.h */
190