include/linux/ip.h

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              Definitions for the IP protocol.
   7  *
   8  * Version:     @(#)ip.h        1.0.2   04/28/93
   9  *
  10  * Authors:     Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  11  *
  12  *              This program is free software; you can redistribute it and/or
  13  *              modify it under the terms of the GNU General Public License
  14  *              as published by the Free Software Foundation; either version
  15  *              2 of the License, or (at your option) any later version.
  16  */
  17 #ifndef _LINUX_IP_H
  18 #define _LINUX_IP_H
  19 #include <asm/byteorder.h>
  20
  21 /* SOL_IP socket options */
  22
  23 #define IPTOS_TOS_MASK          0x1E
  24 #define IPTOS_TOS(tos)          ((tos)&IPTOS_TOS_MASK)
  25 #define IPTOS_LOWDELAY          0x10
  26 #define IPTOS_THROUGHPUT        0x08
  27 #define IPTOS_RELIABILITY       0x04
  28 #define IPTOS_MINCOST           0x02
  29
  30 #define IPTOS_PREC_MASK         0xE0
  31 #define IPTOS_PREC(tos)         ((tos)&IPTOS_PREC_MASK)
  32 #define IPTOS_PREC_NETCONTROL           0xe0
  33 #define IPTOS_PREC_INTERNETCONTROL      0xc0
  34 #define IPTOS_PREC_CRITIC_ECP           0xa0
  35 #define IPTOS_PREC_FLASHOVERRIDE        0x80
  36 #define IPTOS_PREC_FLASH                0x60
  37 #define IPTOS_PREC_IMMEDIATE            0x40
  38 #define IPTOS_PREC_PRIORITY             0x20
  39 #define IPTOS_PREC_ROUTINE              0x00
  40
  41
  42 /* IP options */
  43 #define IPOPT_COPY              0x80
  44 #define IPOPT_CLASS_MASK        0x60
  45 #define IPOPT_NUMBER_MASK       0x1f
  46
  47 #define IPOPT_COPIED(o)         ((o)&IPOPT_COPY)
  48 #define IPOPT_CLASS(o)          ((o)&IPOPT_CLASS_MASK)
  49 #define IPOPT_NUMBER(o)         ((o)&IPOPT_NUMBER_MASK)
  50
  51 #define IPOPT_CONTROL           0x00
  52 #define IPOPT_RESERVED1         0x20
  53 #define IPOPT_MEASUREMENT       0x40
  54 #define IPOPT_RESERVED2         0x60
  55
  56 #define IPOPT_END       (0 |IPOPT_CONTROL)
  57 #define IPOPT_NOOP      (1 |IPOPT_CONTROL)
  58 #define IPOPT_SEC       (2 |IPOPT_CONTROL|IPOPT_COPY)
  59 #define IPOPT_LSRR      (3 |IPOPT_CONTROL|IPOPT_COPY)
  60 #define IPOPT_TIMESTAMP (4 |IPOPT_MEASUREMENT)
  61 #define IPOPT_RR        (7 |IPOPT_CONTROL)
  62 #define IPOPT_SID       (8 |IPOPT_CONTROL|IPOPT_COPY)
  63 #define IPOPT_SSRR      (9 |IPOPT_CONTROL|IPOPT_COPY)
  64 #define IPOPT_RA        (20|IPOPT_CONTROL|IPOPT_COPY)
  65
  66 #define IPVERSION       4
  67 #define MAXTTL          255
  68 #define IPDEFTTL        64
  69
  70 /* struct timestamp, struct route and MAX_ROUTES are removed.
  71
  72    REASONS: it is clear that nobody used them because:
  73    - MAX_ROUTES value was wrong.
  74    - "struct route" was wrong.
  75    - "struct timestamp" had fatally misaligned bitfields and was completely unusable.
  76  */
  77
  78 #define IPOPT_OPTVAL 0
  79 #define IPOPT_OLEN   1
  80 #define IPOPT_OFFSET 2
  81 #define IPOPT_MINOFF 4
  82 #define MAX_IPOPTLEN 40
  83 #define IPOPT_NOP IPOPT_NOOP
  84 #define IPOPT_EOL IPOPT_END
  85 #define IPOPT_TS  IPOPT_TIMESTAMP
  86
  87 #define IPOPT_TS_TSONLY         0               /* timestamps only */
  88 #define IPOPT_TS_TSANDADDR      1               /* timestamps and addresses */
  89 #define IPOPT_TS_PRESPEC        3               /* specified modules only */
  90
  91 struct ip_options {
  92   __u32         faddr;                          /* Saved first hop address */
  93   unsigned char optlen;
  94   unsigned char srr;
  95   unsigned char rr;
  96   unsigned char ts;
  97   unsigned char is_setbyuser:1,                 /* Set by setsockopt?                   */
  98                 is_data:1,                      /* Options in __data, rather than skb   */
  99                 is_strictroute:1,               /* Strict source route                  */
 100                 srr_is_hit:1,                   /* Packet destination addr was our one  */
 101                 is_changed:1,                   /* IP checksum more not valid           */
 102                 rr_needaddr:1,                  /* Need to record addr of outgoing dev  */
 103                 ts_needtime:1,                  /* Need to record timestamp             */
 104                 ts_needaddr:1;                  /* Need to record addr of outgoing dev  */
 105   unsigned char router_alert;
 106   unsigned char __pad1;
 107   unsigned char __pad2;
 108   unsigned char __data[0];
 109 };
 110
 111 #ifdef __KERNEL__
 112 #define optlength(opt) (sizeof(struct ip_options) + opt->optlen)
 113 #endif
 114
 115 struct iphdr {
 116 #if defined(__LITTLE_ENDIAN_BITFIELD)
 117         __u8    ihl:4,
 118                 version:4;
 119 #elif defined (__BIG_ENDIAN_BITFIELD)
 120         __u8    version:4,
 121                 ihl:4;
 122 #else
 123 #error  "Please fix <asm/byteorder.h>"
 124 #endif
 125         __u8    tos;
 126         __u16   tot_len;
 127         __u16   id;
 128         __u16   frag_off;
 129         __u8    ttl;
 130         __u8    protocol;
 131         __u16   check;
 132         __u32   saddr;
 133         __u32   daddr;
 134         /*The options start here. */
 135 };
 136
 137 #endif  /* _LINUX_IP_H */