sys/netinet/ip.h

   1 /*      $NetBSD: ip.h,v 1.30 2007/12/21 02:07:54 matt Exp $     */
   2
   3 /*
   4  * Copyright (c) 1982, 1986, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)ip.h        8.2 (Berkeley) 6/1/94
  32  */
  33
  34 #ifndef _NETINET_IP_H_
  35 #define _NETINET_IP_H_
  36
  37 /*
  38  * Definitions for internet protocol version 4.
  39  * Per RFC 791, September 1981.
  40  */
  41 #define IPVERSION       4
  42
  43 /*
  44  * Structure of an internet header, naked of options.
  45  */
  46 struct ip {
  47 #if BYTE_ORDER == LITTLE_ENDIAN
  48         unsigned int ip_hl:4,           /* header length */
  49                      ip_v:4;            /* version */
  50 #endif
  51 #if BYTE_ORDER == BIG_ENDIAN
  52         unsigned int ip_v:4,            /* version */
  53                      ip_hl:4;           /* header length */
  54 #endif
  55         u_int8_t  ip_tos;               /* type of service */
  56         u_int16_t ip_len;               /* total length */
  57         u_int16_t ip_id;                /* identification */
  58         u_int16_t ip_off;               /* fragment offset field */
  59 #define IP_RF 0x8000                    /* reserved fragment flag */
  60 #define IP_EF 0x8000                    /* evil flag, per RFC 3514 */
  61 #define IP_DF 0x4000                    /* dont fragment flag */
  62 #define IP_MF 0x2000                    /* more fragments flag */
  63 #define IP_OFFMASK 0x1fff               /* mask for fragmenting bits */
  64         u_int8_t  ip_ttl;               /* time to live */
  65         u_int8_t  ip_p;                 /* protocol */
  66         u_int16_t ip_sum;               /* checksum */
  67         struct    in_addr ip_src, ip_dst; /* source and dest address */
  68 } __packed;
  69
  70 #define IP_MAXPACKET    65535           /* maximum packet size */
  71 #define IP_MINFRAGSIZE  69              /* minumum size that can be fraged */
  72
  73 /*
  74  * Definitions for IP type of service (ip_tos)
  75  */
  76 #define IPTOS_LOWDELAY          0x10
  77 #define IPTOS_THROUGHPUT        0x08
  78 #define IPTOS_RELIABILITY       0x04
  79 /*      IPTOS_LOWCOST           0x02 XXX */
  80
  81 /*
  82  * Definitions for IP precedence (also in ip_tos) (hopefully unused)
  83  */
  84 #define IPTOS_PREC_NETCONTROL           0xe0
  85 #define IPTOS_PREC_INTERNETCONTROL      0xc0
  86 #define IPTOS_PREC_CRITIC_ECP           0xa0
  87 #define IPTOS_PREC_FLASHOVERRIDE        0x80
  88 #define IPTOS_PREC_FLASH                0x60
  89 #define IPTOS_PREC_IMMEDIATE            0x40
  90 #define IPTOS_PREC_PRIORITY             0x20
  91 #define IPTOS_PREC_ROUTINE              0x00
  92
  93 /*
  94  * ECN (Explicit Congestion Notification) codepoints in RFC3168
  95  * mapped to the lower 2 bits of the TOS field.
  96  */
  97 #define IPTOS_ECN_NOTECT        0x00    /* not-ECT */
  98 #define IPTOS_ECN_ECT1          0x01    /* ECN-capable transport (1) */
  99 #define IPTOS_ECN_ECT0          0x02    /* ECN-capable transport (0) */
 100 #define IPTOS_ECN_CE            0x03    /* congestion experienced */
 101 #define IPTOS_ECN_MASK          0x03    /* ECN field mask */
 102
 103 /*
 104  * Definitions for options.
 105  */
 106 #define IPOPT_COPIED(o)         ((o)&0x80)
 107 #define IPOPT_CLASS(o)          ((o)&0x60)
 108 #define IPOPT_NUMBER(o)         ((o)&0x1f)
 109
 110 #define IPOPT_CONTROL           0x00
 111 #define IPOPT_RESERVED1         0x20
 112 #define IPOPT_DEBMEAS           0x40
 113 #define IPOPT_RESERVED2         0x60
 114
 115 #define IPOPT_EOL               0               /* end of option list */
 116 #define IPOPT_NOP               1               /* no operation */
 117
 118 #define IPOPT_RR                7               /* record packet route */
 119 #define IPOPT_TS                68              /* timestamp */
 120 #define IPOPT_SECURITY          130             /* provide s,c,h,tcc */
 121 #define IPOPT_LSRR              131             /* loose source route */
 122 #define IPOPT_SATID             136             /* satnet id */
 123 #define IPOPT_SSRR              137             /* strict source route */
 124
 125 /*
 126  * Offsets to fields in options other than EOL and NOP.
 127  */
 128 #define IPOPT_OPTVAL            0               /* option ID */
 129 #define IPOPT_OLEN              1               /* option length */
 130 #define IPOPT_OFFSET            2               /* offset within option */
 131 #define IPOPT_MINOFF            4               /* min value of above */
 132
 133 /*
 134  * Time stamp option structure.
 135  */
 136 struct  ip_timestamp {
 137         u_int8_t ipt_code;              /* IPOPT_TS */
 138         u_int8_t ipt_len;               /* size of structure (variable) */
 139         u_int8_t ipt_ptr;               /* index of current entry */
 140 #if BYTE_ORDER == LITTLE_ENDIAN
 141         unsigned int ipt_flg:4,         /* flags, see below */
 142                      ipt_oflw:4;        /* overflow counter */
 143 #endif
 144 #if BYTE_ORDER == BIG_ENDIAN
 145         unsigned int ipt_oflw:4,        /* overflow counter */
 146                      ipt_flg:4;         /* flags, see below */
 147 #endif
 148         union ipt_timestamp {
 149                  n_time ipt_time[1];
 150                  struct ipt_ta {
 151                         struct in_addr ipt_addr;
 152                         n_time ipt_time;
 153                  } ipt_ta[1] __packed;
 154         } ipt_timestamp __packed;
 155 } __packed;
 156
 157 /* flag bits for ipt_flg */
 158 #define IPOPT_TS_TSONLY         0               /* timestamps only */
 159 #define IPOPT_TS_TSANDADDR      1               /* timestamps and addresses */
 160 #define IPOPT_TS_PRESPEC        3               /* specified modules only */
 161
 162 /* bits for security (not byte swapped) */
 163 #define IPOPT_SECUR_UNCLASS     0x0000
 164 #define IPOPT_SECUR_CONFID      0xf135
 165 #define IPOPT_SECUR_EFTO        0x789a
 166 #define IPOPT_SECUR_MMMM        0xbc4d
 167 #define IPOPT_SECUR_RESTR       0xaf13
 168 #define IPOPT_SECUR_SECRET      0xd788
 169 #define IPOPT_SECUR_TOPSECRET   0x6bc5
 170
 171 /*
 172  * Internet implementation parameters.
 173  */
 174 #define MAXTTL          255             /* maximum time to live (seconds) */
 175 #define IPDEFTTL        64              /* default ttl, from RFC 1340 */
 176 #define IPFRAGTTL       60              /* time to live for frags, slowhz */
 177 #define IPTTLDEC        1               /* subtracted when forwarding */
 178
 179 #define IP_MSS          576             /* default maximum segment size */
 180
 181 /*
 182  * This is the real IPv4 pseudo header, used for computing the TCP and UDP
 183  * checksums. For the Internet checksum, struct ipovly can be used instead.
 184  * For stronger checksums, the real thing must be used.
 185  */
 186 struct ippseudo {
 187         struct  in_addr ippseudo_src;   /* source internet address */
 188         struct  in_addr ippseudo_dst;   /* destination internet address */
 189         u_int8_t        ippseudo_pad;   /* pad, must be zero */
 190         u_int8_t        ippseudo_p;     /* protocol */
 191         u_int16_t       ippseudo_len;   /* protocol length */
 192 } __packed;
 193 #endif /* !_NETINET_IP_H_ */
 194