mirror of
https://github.com/genodelabs/genode.git
synced 2024-12-28 01:28:53 +00:00
276 lines
7.3 KiB
C++
276 lines
7.3 KiB
C++
/*
|
|
* \brief Internet protocol version 4.
|
|
* \author Stefan Kalkowski
|
|
* \date 2010-08-19
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2010-2013 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU General Public License version 2.
|
|
*/
|
|
|
|
#ifndef _IPV4_H_
|
|
#define _IPV4_H_
|
|
|
|
/* Genode */
|
|
#include <base/exception.h>
|
|
#include <util/string.h>
|
|
#include <util/token.h>
|
|
|
|
#include <util/endian.h>
|
|
#include <net/netaddress.h>
|
|
|
|
namespace Net
|
|
{
|
|
enum { IPV4_ADDR_LEN = 4 };
|
|
typedef Network_address<IPV4_ADDR_LEN, '.', false> Ipv4_address;
|
|
|
|
class Ipv4_address_prefix;
|
|
|
|
class Ipv4_packet;
|
|
}
|
|
|
|
|
|
/**
|
|
* Data layout of this class conforms to an IPv4 packet (RFC 791)
|
|
*
|
|
* IPv4-header-format:
|
|
*
|
|
* ----------------------------------------------------------------
|
|
* | 0-3 | 4-7 | 8-11 | 12-15 | 16-18 | 19-23 | 24-27 | 28-31 |
|
|
* ----------------------------------------------------------------
|
|
* | version | IHL | service-type | total-length |
|
|
* ----------------------------------------------------------------
|
|
* | identifikation | flags | fragment-offset |
|
|
* ----------------------------------------------------------------
|
|
* | ttl | protocol | header-checksum |
|
|
* ----------------------------------------------------------------
|
|
* | source-ip-address |
|
|
* ----------------------------------------------------------------
|
|
* | destination-ip-address |
|
|
* ----------------------------------------------------------------
|
|
* | options ... |
|
|
* ----------------------------------------------------------------
|
|
*/
|
|
class Net::Ipv4_packet
|
|
{
|
|
public:
|
|
|
|
enum Size {
|
|
ADDR_LEN = IPV4_ADDR_LEN, /* Ip address length in bytes */
|
|
};
|
|
|
|
static const Ipv4_address CURRENT; /* current network */
|
|
static const Ipv4_address BROADCAST; /* broadcast address */
|
|
|
|
static Ipv4_address ip_from_string(const char *ip);
|
|
|
|
static Genode::uint16_t calculate_checksum(Ipv4_packet const &packet);
|
|
|
|
private:
|
|
|
|
/************************
|
|
** IPv4 header fields **
|
|
************************/
|
|
|
|
unsigned _header_length : 4;
|
|
unsigned _version : 4;
|
|
Genode::uint8_t _diff_service;
|
|
Genode::uint16_t _total_length;
|
|
Genode::uint16_t _identification;
|
|
unsigned _flags : 3;
|
|
unsigned _fragment_offset : 13;
|
|
Genode::uint8_t _time_to_live;
|
|
Genode::uint8_t _protocol;
|
|
Genode::uint16_t _header_checksum;
|
|
Genode::uint8_t _src_addr[ADDR_LEN];
|
|
Genode::uint8_t _dst_addr[ADDR_LEN];
|
|
unsigned _data[0];
|
|
|
|
/**
|
|
* Bitmasks for differentiated services field.
|
|
*/
|
|
enum Differentiated_services {
|
|
PRECEDENCE = 0x7,
|
|
DELAY = 0x8,
|
|
THROUGHPUT = 0x10,
|
|
RELIABILITY = 0x20,
|
|
COST = 0x40
|
|
};
|
|
|
|
public:
|
|
|
|
enum Precedence {
|
|
NETWORK_CONTROL = 7,
|
|
INTERNETWORK_CONTROL = 6,
|
|
CRITIC_ECP = 5,
|
|
FLASH_OVERRIDE = 4,
|
|
FLASH = 3,
|
|
IMMEDIATE = 2,
|
|
PRIORITY = 1,
|
|
ROUTINE = 0
|
|
};
|
|
|
|
enum Flags {
|
|
NO_FRAGMENT = 0x2,
|
|
MORE_FRAGMENTS = 0x4
|
|
};
|
|
|
|
|
|
/**
|
|
* Exception used to indicate protocol violation.
|
|
*/
|
|
class No_ip_packet : Genode::Exception {};
|
|
|
|
|
|
/*****************
|
|
** Constructor **
|
|
*****************/
|
|
|
|
Ipv4_packet(Genode::size_t size) {
|
|
/* ip header needs to fit in */
|
|
if (size < sizeof(Ipv4_packet))
|
|
throw No_ip_packet();
|
|
}
|
|
|
|
|
|
/*******************************
|
|
** IPv4 field read-accessors **
|
|
*******************************/
|
|
|
|
Genode::uint8_t version() { return _version; }
|
|
|
|
/* returns the number of 32-bit words the header occupies */
|
|
Genode::uint8_t header_length() { return _header_length; }
|
|
Genode::uint8_t precedence() { return _diff_service & PRECEDENCE; }
|
|
|
|
bool low_delay() { return _diff_service & DELAY; }
|
|
bool high_throughput() { return _diff_service & THROUGHPUT; }
|
|
bool high_reliability() { return _diff_service & RELIABILITY;}
|
|
bool minimize_monetary_cost() { return _diff_service & COST; }
|
|
|
|
Genode::uint16_t total_length() { return host_to_big_endian(_total_length); }
|
|
Genode::uint16_t identification() { return host_to_big_endian(_identification); }
|
|
|
|
bool no_fragmentation() { return _flags & NO_FRAGMENT; }
|
|
bool more_fragments() { return _flags & MORE_FRAGMENTS; }
|
|
|
|
Genode::size_t fragment_offset() { return _fragment_offset; }
|
|
Genode::uint8_t time_to_live() { return _time_to_live; }
|
|
Genode::uint8_t protocol() { return _protocol; }
|
|
|
|
Genode::uint16_t checksum() { return host_to_big_endian(_header_checksum); }
|
|
|
|
Ipv4_address dst() { return Ipv4_address(&_dst_addr); }
|
|
Ipv4_address src() { return Ipv4_address(&_src_addr); }
|
|
|
|
template <typename T> T const * header() const { return (T const *)(this); }
|
|
template <typename T> T * data() { return (T *)(_data); }
|
|
template <typename T> T const * data() const { return (T const *)(_data); }
|
|
|
|
/********************************
|
|
** IPv4 field write-accessors **
|
|
********************************/
|
|
|
|
void version(Genode::size_t version) { _version = version; }
|
|
void header_length(Genode::size_t len) { _header_length = len; }
|
|
|
|
void total_length(Genode::uint16_t len) { _total_length = host_to_big_endian(len); }
|
|
void time_to_live(Genode::uint8_t ttl) { _time_to_live = ttl; }
|
|
|
|
void checksum(Genode::uint16_t checksum) { _header_checksum = host_to_big_endian(checksum); }
|
|
|
|
void dst(Ipv4_address ip) { ip.copy(&_dst_addr); }
|
|
void src(Ipv4_address ip) { ip.copy(&_src_addr); }
|
|
|
|
/***************
|
|
** Operators **
|
|
***************/
|
|
|
|
/**
|
|
* Placement new.
|
|
*/
|
|
void * operator new(__SIZE_TYPE__ size, void* addr) { return addr; }
|
|
|
|
} __attribute__((packed));
|
|
|
|
|
|
struct Net::Ipv4_address_prefix
|
|
{
|
|
Ipv4_address address;
|
|
Genode::uint8_t prefix = 0;
|
|
};
|
|
|
|
|
|
namespace Genode {
|
|
|
|
inline size_t ascii_to(char const *s, Net::Ipv4_address &result);
|
|
|
|
inline size_t ascii_to(char const *s, Net::Ipv4_address_prefix &result);
|
|
}
|
|
|
|
|
|
Genode::size_t Genode::ascii_to(char const *s, Net::Ipv4_address &result)
|
|
{
|
|
using namespace Net;
|
|
|
|
struct Scanner_policy_number
|
|
{
|
|
static bool identifier_char(char c, unsigned i ) {
|
|
return Genode::is_digit(c) && c !='.'; }
|
|
};
|
|
|
|
typedef ::Genode::Token<Scanner_policy_number> Token;
|
|
|
|
Ipv4_address ip_addr;
|
|
Token t(s);
|
|
char tmpstr[4];
|
|
int cnt = 0;
|
|
unsigned char ipb[4] = {0};
|
|
size_t size = 0;
|
|
|
|
while(t) {
|
|
if (t.type() == Token::WHITESPACE || t[0] == '.') {
|
|
t = t.next();
|
|
size++;
|
|
continue;
|
|
}
|
|
t.string(tmpstr, sizeof(tmpstr));
|
|
|
|
unsigned long tmpc = 0;
|
|
size += Genode::ascii_to(tmpstr, tmpc);
|
|
ipb[cnt] = tmpc & 0xFF;
|
|
t = t.next();
|
|
|
|
if (cnt == 4)
|
|
break;
|
|
cnt++;
|
|
}
|
|
|
|
if (cnt == 4) {
|
|
result.addr[0] = ipb[0];
|
|
result.addr[1] = ipb[1];
|
|
result.addr[2] = ipb[2];
|
|
result.addr[3] = ipb[3];
|
|
return size;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
Genode::size_t Genode::ascii_to(char const *s, Net::Ipv4_address_prefix &result)
|
|
{
|
|
size_t size = ascii_to(s, result.address);
|
|
if (!size || s[size] != '/') { return 0; }
|
|
char const * prefix = &s[size + 1];
|
|
size_t const prefix_size = ascii_to_unsigned(prefix, result.prefix, 10);
|
|
if (!prefix_size) { return 0; }
|
|
size += prefix_size + 1;
|
|
return size;
|
|
}
|
|
|
|
#endif /* _IPV4_H_ */
|