ext/dnet/ip6.h

   1 /*
   2  * ip6.h
   3  *
   4  * Internet Protocol, Version 6 (RFC 2460).
   5  *
   6  * Copyright (c) 2002 Dug Song <dugsong@monkey.org>
   7  *
   8  * $Id: ip6.h,v 1.6 2004/02/23 10:01:15 dugsong Exp $
   9  */
  10
  11 #ifndef DNET_IP6_H
  12 #define DNET_IP6_H
  13
  14 #define IP6_ADDR_LEN    16
  15 #define IP6_ADDR_BITS   128
  16
  17 #define IP6_HDR_LEN     40              /* IPv6 header length */
  18 #define IP6_LEN_MIN     IP6_HDR_LEN
  19 #define IP6_LEN_MAX     65535           /* non-jumbo payload */
  20
  21 #define IP6_MTU_MIN     1280            /* minimum MTU (1024 + 256) */
  22
  23 typedef struct ip6_addr {
  24         uint8_t         data[IP6_ADDR_LEN];
  25 } ip6_addr_t;
  26
  27 #ifndef __GNUC__
  28 # define __attribute__(x)
  29 # pragma pack(1)
  30 #endif
  31
  32 /*
  33  * IPv6 header
  34  */
  35 struct ip6_hdr {
  36         union {
  37                 struct ip6_hdr_ctl {
  38                         uint32_t        ip6_un1_flow; /* 20 bits of flow ID */
  39                         uint16_t        ip6_un1_plen; /* payload length */
  40                         uint8_t         ip6_un1_nxt;  /* next header */
  41                         uint8_t         ip6_un1_hlim; /* hop limit */
  42                 } ip6_un1;
  43                 uint8_t ip6_un2_vfc;    /* 4 bits version, top 4 bits class */
  44         } ip6_ctlun;
  45         ip6_addr_t      ip6_src;
  46         ip6_addr_t      ip6_dst;
  47 } __attribute__((__packed__));
  48
  49 #define ip6_vfc         ip6_ctlun.ip6_un2_vfc
  50 #define ip6_flow        ip6_ctlun.ip6_un1.ip6_un1_flow
  51 #define ip6_plen        ip6_ctlun.ip6_un1.ip6_un1_plen
  52 #define ip6_nxt         ip6_ctlun.ip6_un1.ip6_un1_nxt   /* IP_PROTO_* */
  53 #define ip6_hlim        ip6_ctlun.ip6_un1.ip6_un1_hlim
  54
  55 #define IP6_VERSION             0x60
  56 #define IP6_VERSION_MASK        0xf0            /* ip6_vfc version */
  57
  58 #if DNET_BYTESEX == DNET_BIG_ENDIAN
  59 #define IP6_FLOWINFO_MASK       0x0fffffff      /* ip6_flow info (28 bits) */
  60 #define IP6_FLOWLABEL_MASK      0x000fffff      /* ip6_flow label (20 bits) */
  61 #elif DNET_BYTESEX == DNET_LIL_ENDIAN
  62 #define IP6_FLOWINFO_MASK       0xffffff0f      /* ip6_flow info (28 bits) */
  63 #define IP6_FLOWLABEL_MASK      0xffff0f00      /* ip6_flow label (20 bits) */
  64 #endif
  65
  66 /*
  67  * Hop limit (ip6_hlim)
  68  */
  69 #define IP6_HLIM_DEFAULT        64
  70 #define IP6_HLIM_MAX            255
  71
  72 /*
  73  * Preferred extension header order from RFC 2460, 4.1:
  74  *
  75  * IP_PROTO_IPV6, IP_PROTO_HOPOPTS, IP_PROTO_DSTOPTS, IP_PROTO_ROUTING,
  76  * IP_PROTO_FRAGMENT, IP_PROTO_AH, IP_PROTO_ESP, IP_PROTO_DSTOPTS, IP_PROTO_*
  77  */
  78
  79 /*
  80  * Routing header data (IP_PROTO_ROUTING)
  81  */
  82 struct ip6_ext_data_routing {
  83         uint8_t  type;                  /* routing type */
  84         uint8_t  segleft;               /* segments left */
  85         /* followed by routing type specific data */
  86 } __attribute__((__packed__));
  87
  88 struct ip6_ext_data_routing0 {
  89         uint8_t  type;                  /* always zero */
  90         uint8_t  segleft;               /* segments left */
  91         uint8_t  reserved;              /* reserved field */
  92         uint8_t  slmap[3];              /* strict/loose bit map */
  93         ip6_addr_t  addr[1];            /* up to 23 addresses */
  94 } __attribute__((__packed__));
  95
  96 /*
  97  * Fragment header data (IP_PROTO_FRAGMENT)
  98  */
  99 struct ip6_ext_data_fragment {
 100         uint16_t  offlg;                /* offset, reserved, and flag */
 101         uint32_t  ident;                /* identification */
 102 } __attribute__((__packed__));
 103
 104 /*
 105  * Fragmentation offset, reserved, and flags (offlg)
 106  */
 107 #if DNET_BYTESEX == DNET_BIG_ENDIAN
 108 #define IP6_OFF_MASK            0xfff8  /* mask out offset from offlg */
 109 #define IP6_RESERVED_MASK       0x0006  /* reserved bits in offlg */
 110 #define IP6_MORE_FRAG           0x0001  /* more-fragments flag */
 111 #elif DNET_BYTESEX == DNET_LIL_ENDIAN
 112 #define IP6_OFF_MASK            0xf8ff  /* mask out offset from offlg */
 113 #define IP6_RESERVED_MASK       0x0600  /* reserved bits in offlg */
 114 #define IP6_MORE_FRAG           0x0100  /* more-fragments flag */
 115 #endif
 116
 117 /*
 118  * Option types, for IP_PROTO_HOPOPTS, IP_PROTO_DSTOPTS headers
 119  */
 120 #define IP6_OPT_PAD1            0x00    /* 00 0 00000 */
 121 #define IP6_OPT_PADN            0x01    /* 00 0 00001 */
 122 #define IP6_OPT_JUMBO           0xC2    /* 11 0 00010 = 194 */
 123 #define IP6_OPT_JUMBO_LEN       6
 124 #define IP6_OPT_RTALERT         0x05    /* 00 0 00101 */
 125 #define IP6_OPT_RTALERT_LEN     4
 126 #define IP6_OPT_RTALERT_MLD     0       /* Datagram contains an MLD message */
 127 #define IP6_OPT_RTALERT_RSVP    1       /* Datagram contains an RSVP message */
 128 #define IP6_OPT_RTALERT_ACTNET  2       /* contains an Active Networks msg */
 129 #define IP6_OPT_LEN_MIN         2
 130
 131 #define IP6_OPT_TYPE(o)         ((o) & 0xC0)    /* high 2 bits of opt_type */
 132 #define IP6_OPT_TYPE_SKIP       0x00    /* continue processing on failure */
 133 #define IP6_OPT_TYPE_DISCARD    0x40    /* discard packet on failure */
 134 #define IP6_OPT_TYPE_FORCEICMP  0x80    /* discard and send ICMP on failure */
 135 #define IP6_OPT_TYPE_ICMP       0xC0    /* ...only if non-multicast dst */
 136
 137 #define IP6_OPT_MUTABLE         0x20    /* option data may change en route */
 138
 139 /*
 140  * Extension header (chained via {ip6,ext}_nxt, following IPv6 header)
 141  */
 142 struct ip6_ext_hdr {
 143         uint8_t  ext_nxt;       /* next header */
 144         uint8_t  ext_len;       /* following length in units of 8 octets */
 145         union {
 146                 struct ip6_ext_data_routing     routing;
 147                 struct ip6_ext_data_fragment    fragment;
 148         } ext_data;
 149 } __attribute__((__packed__));
 150
 151 #ifndef __GNUC__
 152 # pragma pack()
 153 #endif
 154
 155 /*
 156  * Reserved addresses
 157  */
 158 #define IP6_ADDR_UNSPEC \
 159         "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
 160 #define IP6_ADDR_LOOPBACK \
 161         "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01"
 162
 163 #define ip6_pack_hdr(hdr, fc, fl, plen, nxt, hlim, src, dst) do {       \
 164         struct ip6_hdr *ip6 = (struct ip6_hdr *)(hdr);                  \
 165         ip6->ip6_flow = htonl(((uint32_t)(fc) << 28) &                  \
 166             (IP6_FLOWLABEL_MASK | (fl)));                               \
 167         ip6->ip6_vfc = (IP6_VERSION | ((fc) >> 4));                     \
 168         ip6->ip6_plen = htons((plen));                                  \
 169         ip6->ip6_nxt = (nxt); ip6->ip6_hlim = (hlim);                   \
 170         memmove(&ip6->ip6_src, &(src), IP6_ADDR_LEN);                   \
 171         memmove(&ip6->ip6_dst, &(dst), IP6_ADDR_LEN);                   \
 172 } while (0);
 173
 174 __BEGIN_DECLS
 175 char    *ip6_ntop(const ip6_addr_t *ip6, char *dst, size_t size);
 176 int      ip6_pton(const char *src, ip6_addr_t *dst);
 177 char    *ip6_ntoa(const ip6_addr_t *ip6);
 178 #define  ip6_aton ip6_pton
 179
 180 void     ip6_checksum(void *buf, size_t len);
 181 __END_DECLS
 182
 183 #endif /* DNET_IP6_H */