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  * Definitions for IP precedence (also in ip_tos) (deprecated).
 106  */
 107 #define IPTOS_PREC_NETCONTROL           IPTOS_DSCP_CS7
 108 #define IPTOS_PREC_INTERNETCONTROL      IPTOS_DSCP_CS6
 109 #define IPTOS_PREC_CRITIC_ECP           IPTOS_DSCP_CS5
 110 #define IPTOS_PREC_FLASHOVERRIDE        IPTOS_DSCP_CS4
 111 #define IPTOS_PREC_FLASH                IPTOS_DSCP_CS3
 112 #define IPTOS_PREC_IMMEDIATE            IPTOS_DSCP_CS2
 113 #define IPTOS_PREC_PRIORITY             IPTOS_DSCP_CS1
 114 #define IPTOS_PREC_ROUTINE              IPTOS_DSCP_CS0
 115
 116 /*
 117  * Definitions for DiffServ Codepoints as per RFC2474 and RFC5865.
 118  */
 119 #define IPTOS_DSCP_CS0          0x00
 120 #define IPTOS_DSCP_CS1          0x20
 121 #define IPTOS_DSCP_AF11         0x28
 122 #define IPTOS_DSCP_AF12         0x30
 123 #define IPTOS_DSCP_AF13         0x38
 124 #define IPTOS_DSCP_CS2          0x40
 125 #define IPTOS_DSCP_AF21         0x48
 126 #define IPTOS_DSCP_AF22         0x50
 127 #define IPTOS_DSCP_AF23         0x58
 128 #define IPTOS_DSCP_CS3          0x60
 129 #define IPTOS_DSCP_AF31         0x68
 130 #define IPTOS_DSCP_AF32         0x70
 131 #define IPTOS_DSCP_AF33         0x78
 132 #define IPTOS_DSCP_CS4          0x80
 133 #define IPTOS_DSCP_AF41         0x88
 134 #define IPTOS_DSCP_AF42         0x90
 135 #define IPTOS_DSCP_AF43         0x98
 136 #define IPTOS_DSCP_CS5          0xa0
 137 #define IPTOS_DSCP_VA           0xb0
 138 #define IPTOS_DSCP_EF           0xb8
 139 #define IPTOS_DSCP_CS6          0xc0
 140 #define IPTOS_DSCP_CS7          0xe0
 141
 142 /*
 143  * ECN (Explicit Congestion Notification) codepoints in RFC3168
 144  * mapped to the lower 2 bits of the TOS field.
 145  */
 146 #define IPTOS_ECN_NOTECT        0x00    /* not-ECT */
 147 #define IPTOS_ECN_ECT1          0x01    /* ECN-capable transport (1) */
 148 #define IPTOS_ECN_ECT0          0x02    /* ECN-capable transport (0) */
 149 #define IPTOS_ECN_CE            0x03    /* congestion experienced */
 150 #define IPTOS_ECN_MASK          0x03    /* ECN field mask */
 151
 152 /*
 153  * Definitions for options.
 154  */
 155 #define IPOPT_COPIED(o)         ((o)&0x80)
 156 #define IPOPT_CLASS(o)          ((o)&0x60)
 157 #define IPOPT_NUMBER(o)         ((o)&0x1f)
 158
 159 #define IPOPT_CONTROL           0x00
 160 #define IPOPT_RESERVED1         0x20
 161 #define IPOPT_DEBMEAS           0x40
 162 #define IPOPT_RESERVED2         0x60
 163
 164 #define IPOPT_EOL               0               /* end of option list */
 165 #define IPOPT_NOP               1               /* no operation */
 166
 167 #define IPOPT_RR                7               /* record packet route */
 168 #define IPOPT_TS                68              /* timestamp */
 169 #define IPOPT_SECURITY          130             /* provide s,c,h,tcc */
 170 #define IPOPT_LSRR              131             /* loose source route */
 171 #define IPOPT_SATID             136             /* satnet id */
 172 #define IPOPT_SSRR              137             /* strict source route */
 173 #define IPOPT_RA                148             /* router alert */
 174
 175 /*
 176  * Offsets to fields in options other than EOL and NOP.
 177  */
 178 #define IPOPT_OPTVAL            0               /* option ID */
 179 #define IPOPT_OLEN              1               /* option length */
 180 #define IPOPT_OFFSET            2               /* offset within option */
 181 #define IPOPT_MINOFF            4               /* min value of above */
 182
 183 /*
 184  * Time stamp option structure.
 185  */
 186 struct  ip_timestamp {
 187         u_char  ipt_code;               /* IPOPT_TS */
 188         u_char  ipt_len;                /* size of structure (variable) */
 189         u_char  ipt_ptr;                /* index of current entry */
 190 #if _BYTE_ORDER == _LITTLE_ENDIAN
 191         u_int   ipt_flg:4,              /* flags, see below */
 192                 ipt_oflw:4;             /* overflow counter */
 193 #elif _BYTE_ORDER == _BIG_ENDIAN
 194         u_int   ipt_oflw:4,             /* overflow counter */
 195                 ipt_flg:4;              /* flags, see below */
 196 #else
 197 #error "Byte order not implemented"
 198 #endif
 199         union ipt_timestamp {
 200                 n_long  ipt_time[1];
 201                 struct  ipt_ta {
 202                         struct in_addr ipt_addr;
 203                         n_long ipt_time;
 204                 } ipt_ta[1];
 205         } ipt_timestamp;
 206 };
 207
 208 /* Flag bits for ipt_flg. */
 209 #define IPOPT_TS_TSONLY         0               /* timestamps only */
 210 #define IPOPT_TS_TSANDADDR      1               /* timestamps and addresses */
 211 #define IPOPT_TS_PRESPEC        3               /* specified modules only */
 212
 213 /* Bits for security (not byte swapped). */
 214 #define IPOPT_SECUR_UNCLASS     0x0000
 215 #define IPOPT_SECUR_CONFID      0xf135
 216 #define IPOPT_SECUR_EFTO        0x789a
 217 #define IPOPT_SECUR_MMMM        0xbc4d
 218 #define IPOPT_SECUR_RESTR       0xaf13
 219 #define IPOPT_SECUR_SECRET      0xd788
 220 #define IPOPT_SECUR_TOPSECRET   0x6bc5
 221
 222 /*
 223  * Internet implementation parameters.
 224  */
 225 #define MAXTTL          255             /* maximum time to live (seconds) */
 226 #define IPDEFTTL        64              /* default ttl, from RFC 1340 */
 227 #define IPFRAGTTL       60              /* time to live for frags, slowhz */
 228 #define IPTTLDEC        1               /* subtracted when forwarding */
 229 #define IP_MSS          576             /* default maximum segment size */
 230
 231 /*
 232  * This is the real IPv4 pseudo header, used for computing the TCP and UDP
 233  * checksums. For the Internet checksum, struct ipovly can be used instead.
 234  * For stronger checksums, the real thing must be used.
 235  */
 236 struct ippseudo {
 237         struct  in_addr ippseudo_src;   /* source internet address */
 238         struct  in_addr ippseudo_dst;   /* destination internet address */
 239         u_int8_t        ippseudo_pad;   /* pad, must be zero */
 240         u_int8_t        ippseudo_p;     /* protocol */
 241         u_int16_t       ippseudo_len;   /* protocol length */
 242 } __packed;
 243 #endif