Subversion Repositories HelenOS

Rev

Rev 4350 | Rev 4722 | Go to most recent revision | Blame | Compare with Previous | Last modification | View Log | Download | RSS feed

  1. /*
  2.  * Copyright (c) 2009 Lukas Mejdrech
  3.  * 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.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup ip
  30.  *  @{
  31.  */
  32.  
  33. /** @file
  34.  *  Internet protocol header and options definitions.
  35.  *  Names according to the linux src/include/linux/ip.h header file.
  36.  */
  37.  
  38. #ifndef __NET_IP_HEADER_H__
  39. #define __NET_IP_HEADER_H__
  40.  
  41. #include <byteorder.h>
  42. #include <sys/types.h>
  43.  
  44. /** Type definition of the internet header.
  45.  *  @see ip_header
  46.  */
  47. typedef struct ip_header    ip_header_t;
  48.  
  49. /** Type definition of the internet header pointer.
  50.  *  @see ip_header
  51.  */
  52. typedef ip_header_t *       ip_header_ref;
  53.  
  54. /** Internet header.
  55.  *  The variable options should be included after the header itself and indicated by the increased header length value.
  56.  */
  57. struct ip_header{
  58. #ifdef ARCH_IS_BIG_ENDIAN
  59.     /** The Version field indicates the format of the internet header.
  60.      */
  61.     uint8_t     version:4;
  62.     /** Internet Header Length is the length of the internet header in 32~bit words, and thus points to the beginning of the data.
  63.      *  Note that the minimum value for a~correct header is~5.
  64.      */
  65.     uint8_t     ihl:4;
  66. #else
  67.     /** Internet Header Length is the length of the internet header in 32~bit words, and thus points to the beginning of the data.
  68.      *  Note that the minimum value for a~correct header is~5.
  69.      */
  70.     uint8_t     ihl:4;
  71.     /** The Version field indicates the format of the internet header.
  72.      */
  73.     uint8_t     version:4;
  74. #endif
  75.     /** The Type of Service provides an indication of the abstract parameters of the quality of service desired.
  76.      *  These parameters are to be used to guide the selection of the actual service parameters when transmitting a~datagram through a~particular network.
  77.      *  Several networks offer service precedence, which somehow treats high precedence traffic as more important than other traffic (generally by accepting only traffic above a~certain precedence at time of high load).
  78.      *  The major choice is a~three way tradeoff between low-delay, high-reliability, and high-throughput.
  79.      */
  80.     uint8_t     tos;
  81.     /** Total Length is the length of the datagram, measured in octets, including internet header and data.
  82.      *  This field allows the length of a~datagram to be up to 65,535~octets.
  83.      */
  84.     uint16_t    total_length;
  85.     /** An identifying value assigned by the sender to aid in assembling the fragments of a~datagram.
  86.      */
  87.     uint16_t    identification;
  88. #ifdef ARCH_IS_BIG_ENDIAN
  89.     /** Various control flags.
  90.      */
  91.     uint16_t    flags:3;
  92.     /** This field indicates where in the datagram this fragment belongs.
  93.      */
  94.     uint16_t    fragment_offset:3;
  95. #else
  96.     /** This field indicates where in the datagram this fragment belongs.
  97.      */
  98.     uint16_t    fragment_offset:13;
  99.     /** Various control flags.
  100.      */
  101.     uint16_t    flags:3;
  102. #endif
  103.     /** This field indicates the maximum time the datagram is allowed to remain in the internet system.
  104.      *  If this field contains the value zero, then the datagram must be destroyed.
  105.      *  This field is modified in internet header processing.
  106.      *  The time is measured in units of seconds, but since every module that processes a~datagram must decrease the TTL by at least one even if it process the datagram in less than a~second, the TTL must be thought of only as an upper bound on the time a~datagram may exist.
  107.      *  The intention is to cause undeliverable datagrams to be discarded, and to bound the maximum datagram lifetime.
  108.      */
  109.     uint8_t     ttl;
  110.     /** This field indicates the next level protocol used in the data portion of the internet datagram.
  111.      */
  112.     uint8_t     protocol;
  113.     /** A checksum of the header only.
  114.      *  Since some header fields change (e.g., time to live), this is recomputed and verified at each point that the internet header is processed.
  115.      *  The checksum algorithm is: The checksum field is the 16~bit one's complement of the one's complement sum of all 16~bit words in the header.
  116.      *  For purposes of computing the checksum, the value of the checksum field is zero.
  117.      */
  118.     uint16_t    header_checksum;
  119.     /** The source address.
  120.      */
  121.     uint32_t    source_address;
  122.     /** The destination address.
  123.      */
  124.     uint32_t    destination_address;
  125. } __attribute__ ((packed));
  126.  
  127. /** Type definition of the internet option header.
  128.  *  @see ip_header
  129.  */
  130. typedef struct ip_option    ip_option_t;
  131.  
  132. /** Type definition of the internet option header pointer.
  133.  *  @see ip_header
  134.  */
  135. typedef ip_option_t *       ip_option_ref;
  136.  
  137. /** Internet option header.
  138.  *  Only type field is always valid.
  139.  *  Other fields' validity depends on the option type.
  140.  */
  141. struct ip_option{
  142.     /** A single octet of option-type.
  143.      */
  144.     uint8_t     type;
  145.     /** An option length octet.
  146.      */
  147.     uint8_t     length;
  148.     /** A~pointer.
  149.      */
  150.     uint8_t     pointer;
  151. #ifdef ARCH_IS_BIG_ENDIAN
  152.     /** The number of IP modules that cannot register timestamps due to lack of space.
  153.      */
  154.     uint8_t overflow:4;
  155.     /** Various internet timestamp control flags.
  156.      */
  157.     uint8_t flags:4;
  158. #else
  159.     /** Various internet timestamp control flags.
  160.      */
  161.     uint8_t flags:4;
  162.     /** The number of IP modules that cannot register timestamps due to lack of space.
  163.      */
  164.     uint8_t overflow:4;
  165. #endif
  166. } __attribute__ ((packed));
  167.  
  168. #define IPFLAG_FRAGMENT_SHIFT       1
  169. #define IPFLAG_FRAGMENTED_SHIFT     0
  170.  
  171. #define IPFLAG_MAY_FRAGMENT         ( 0x0 << IPFLAG_FRAGMENT_SHIFT )
  172. #define IPFLAG_DONT_FRAGMENT        ( 0x1 << IPFLAG_FRAGMENT_SHIFT )
  173.  
  174. #define IPFLAG_LAST_FRAGMENT        ( 0x0 << IPFLAG_FRAGMENTED_SHIFT )
  175. #define IPFLAG_MORE_FRAGMENTS       ( 0x1 << IPFLAG_FRAGMENTED_SHIFT )
  176.  
  177. /*
  178. #define IPOPT_OPTVAL 0
  179. #define IPOPT_OLEN   1
  180. #define IPOPT_OFFSET 2
  181. #define IPOPT_MINOFF 4
  182. #define MAX_IPOPTLEN 40
  183. */
  184.  
  185. #endif
  186.  
  187. /** @}
  188.  */
  189.