sys/netinet/ip.h

   1 /*
   2  * Copyright (c) 1982, 1986, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)ip.h        8.2 (Berkeley) 6/1/94
  30  * $FreeBSD: src/sys/netinet/ip.h,v 1.17 1999/12/22 19:13:20 shin Exp $
  31  */
  32
  33 #ifndef _NETINET_IP_H_
  34 #define _NETINET_IP_H_
  35
  36 #ifndef _SYS_TYPES_H_
  37 #include <sys/types.h>
  38 #endif
  39 #ifndef _NETINET_IN_H_
  40 #include <netinet/in.h>
  41 #endif
  42 #ifndef _NETINET_IN_SYSTM_H_
  43 #include <netinet/in_systm.h>
  44 #endif
  45 #include <machine/endian.h>
  46
  47 /*
  48  * Definitions for internet protocol version 4.
  49  * Per RFC 791, September 1981.
  50  */
  51 #define IPVERSION       4
  52
  53 /*
  54  * Structure of an internet header, naked of options.
  55  */
  56 struct ip {
  57 #ifdef _IP_VHL
  58         u_char  ip_vhl;                 /* version << 4 | header length >> 2 */
  59 #elif _BYTE_ORDER == _LITTLE_ENDIAN
  60         u_int   ip_hl:4,                /* header length */
  61                 ip_v:4;                 /* version */
  62 #elif _BYTE_ORDER == _BIG_ENDIAN
  63         u_int   ip_v:4,                 /* version */
  64                 ip_hl:4;                /* header length */
  65 #else
  66 #error "Byte order not implemented"
  67 #endif
  68         u_char  ip_tos;                 /* type of service */
  69         u_short ip_len;                 /* total length */
  70         u_short ip_id;                  /* identification */
  71         u_short ip_off;                 /* fragment offset field */
  72 #define IP_RF 0x8000                    /* reserved fragment flag */
  73 #define IP_DF 0x4000                    /* dont fragment flag */
  74 #define IP_MF 0x2000                    /* more fragments flag */
  75 #define IP_OFFMASK 0x1fff               /* mask for fragmenting bits */
  76         u_char  ip_ttl;                 /* time to live */
  77         u_char  ip_p;                   /* protocol */
  78         u_short ip_sum;                 /* checksum */
  79         struct  in_addr ip_src,ip_dst;  /* source and dest address */
  80 };
  81
  82 #ifdef _IP_VHL
  83 #define IP_MAKE_VHL(v, hl)      ((v) << 4 | (hl))
  84 #define IP_VHL_HL(vhl)          ((vhl) & 0x0f)
  85 #define IP_VHL_V(vhl)           ((vhl) >> 4)
  86 #define IP_VHL_BORING           0x45
  87 #endif
  88
  89 #define IP_MAXPACKET    65535           /* maximum packet size */
  90
  91 /*
  92  * Definitions for IP type of service (ip_tos)
  93  */
  94 #define IPTOS_LOWDELAY          0x10
  95 #define IPTOS_THROUGHPUT        0x08
  96 #define IPTOS_RELIABILITY       0x04
  97 #define IPTOS_MINCOST           0x02
  98 #if 1
  99 /* ECN RFC3168 obsoletes RFC2481, and these will be deprecated soon. */
 100 #define IPTOS_CE                0x01    /* congestion experienced */
 101 #define IPTOS_ECT               0x02    /* ECN-capable transport */
 102 #endif
 103
 104
 105 /*
 106  * Definitions for IP precedence (also in ip_tos) (hopefully unused)
 107  */
 108 #define IPTOS_PREC_NETCONTROL           0xe0
 109 #define IPTOS_PREC_INTERNETCONTROL      0xc0
 110 #define IPTOS_PREC_CRITIC_ECP           0xa0
 111 #define IPTOS_PREC_FLASHOVERRIDE        0x80
 112 #define IPTOS_PREC_FLASH                0x60
 113 #define IPTOS_PREC_IMMEDIATE            0x40
 114 #define IPTOS_PREC_PRIORITY             0x20
 115 #define IPTOS_PREC_ROUTINE              0x00
 116
 117 /*
 118  * ECN (Explicit Congestion Notification) codepoints in RFC3168
 119  * mapped to the lower 2 bits of the TOS field.
 120  */
 121 #define IPTOS_ECN_NOTECT        0x00    /* not-ECT */
 122 #define IPTOS_ECN_ECT1          0x01    /* ECN-capable transport (1) */
 123 #define IPTOS_ECN_ECT0          0x02    /* ECN-capable transport (0) */
 124 #define IPTOS_ECN_CE            0x03    /* congestion experienced */
 125 #define IPTOS_ECN_MASK          0x03    /* ECN field mask */
 126
 127 /*
 128  * Definitions for options.
 129  */
 130 #define IPOPT_COPIED(o)         ((o)&0x80)
 131 #define IPOPT_CLASS(o)          ((o)&0x60)
 132 #define IPOPT_NUMBER(o)         ((o)&0x1f)
 133
 134 #define IPOPT_CONTROL           0x00
 135 #define IPOPT_RESERVED1         0x20
 136 #define IPOPT_DEBMEAS           0x40
 137 #define IPOPT_RESERVED2         0x60
 138
 139 #define IPOPT_EOL               0               /* end of option list */
 140 #define IPOPT_NOP               1               /* no operation */
 141
 142 #define IPOPT_RR                7               /* record packet route */
 143 #define IPOPT_TS                68              /* timestamp */
 144 #define IPOPT_SECURITY          130             /* provide s,c,h,tcc */
 145 #define IPOPT_LSRR              131             /* loose source route */
 146 #define IPOPT_SATID             136             /* satnet id */
 147 #define IPOPT_SSRR              137             /* strict source route */
 148 #define IPOPT_RA                148             /* router alert */
 149
 150 /*
 151  * Offsets to fields in options other than EOL and NOP.
 152  */
 153 #define IPOPT_OPTVAL            0               /* option ID */
 154 #define IPOPT_OLEN              1               /* option length */
 155 #define IPOPT_OFFSET            2               /* offset within option */
 156 #define IPOPT_MINOFF            4               /* min value of above */
 157
 158 /*
 159  * Time stamp option structure.
 160  */
 161 struct  ip_timestamp {
 162         u_char  ipt_code;               /* IPOPT_TS */
 163         u_char  ipt_len;                /* size of structure (variable) */
 164         u_char  ipt_ptr;                /* index of current entry */
 165 #if _BYTE_ORDER == _LITTLE_ENDIAN
 166         u_int   ipt_flg:4,              /* flags, see below */
 167                 ipt_oflw:4;             /* overflow counter */
 168 #elif _BYTE_ORDER == _BIG_ENDIAN
 169         u_int   ipt_oflw:4,             /* overflow counter */
 170                 ipt_flg:4;              /* flags, see below */
 171 #else
 172 #error "Byte order not implemented"
 173 #endif
 174         union ipt_timestamp {
 175                 n_long  ipt_time[1];
 176                 struct  ipt_ta {
 177                         struct in_addr ipt_addr;
 178                         n_long ipt_time;
 179                 } ipt_ta[1];
 180         } ipt_timestamp;
 181 };
 182
 183 /* flag bits for ipt_flg */
 184 #define IPOPT_TS_TSONLY         0               /* timestamps only */
 185 #define IPOPT_TS_TSANDADDR      1               /* timestamps and addresses */
 186 #define IPOPT_TS_PRESPEC        3               /* specified modules only */
 187
 188 /* bits for security (not byte swapped) */
 189 #define IPOPT_SECUR_UNCLASS     0x0000
 190 #define IPOPT_SECUR_CONFID      0xf135
 191 #define IPOPT_SECUR_EFTO        0x789a
 192 #define IPOPT_SECUR_MMMM        0xbc4d
 193 #define IPOPT_SECUR_RESTR       0xaf13
 194 #define IPOPT_SECUR_SECRET      0xd788
 195 #define IPOPT_SECUR_TOPSECRET   0x6bc5
 196
 197 /*
 198  * Internet implementation parameters.
 199  */
 200 #define MAXTTL          255             /* maximum time to live (seconds) */
 201 #define IPDEFTTL        64              /* default ttl, from RFC 1340 */
 202 #define IPFRAGTTL       60              /* time to live for frags, slowhz */
 203 #define IPTTLDEC        1               /* subtracted when forwarding */
 204
 205 #define IP_MSS          576             /* default maximum segment size */
 206
 207 /*
 208  * This is the real IPv4 pseudo header, used for computing the TCP and UDP
 209  * checksums. For the Internet checksum, struct ipovly can be used instead.
 210  * For stronger checksums, the real thing must be used.
 211  */
 212 struct ippseudo {
 213         struct  in_addr ippseudo_src;   /* source internet address */
 214         struct  in_addr ippseudo_dst;   /* destination internet address */
 215         u_int8_t        ippseudo_pad;   /* pad, must be zero */
 216         u_int8_t        ippseudo_p;     /* protocol */
 217         u_int16_t       ippseudo_len;   /* protocol length */
 218 } __packed;
 219 #endif