inet/netinet/ip6.h

   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
  25 struct 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.  */
  51 struct 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.  */
  58 struct 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 */
  66 struct 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 */
  74 struct 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 */
  84 struct 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 */
  97 struct 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 */
 116 struct 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 */
 143 struct 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 */
 152 struct 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 */
 163 struct 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 */
 171 struct 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 */