Source: ../../libxorp/ipv4.hh
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// -*- c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t -*-
// Copyright (c) 2001,2002 International Computer Science Institute
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software")
// to deal in the Software without restriction, subject to the conditions
// listed in the XORP LICENSE file. These conditions include: you must
// preserve this copyright notice, and you cannot mention the copyright
// holders in advertising related to the Software without their permission.
// The Software is provided WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED. This
// notice is a summary of the XORP LICENSE file; the license in that file is
// legally binding.
// $XORP: xorp/libxorp/ipv4.hh,v 1.1.1.1 2002/12/11 23:56:05 hodson Exp $
#ifndef __LIBXORP_IPV4_HH__
#define __LIBXORP_IPV4_HH__
#include <string.h>
#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>
#include "config.h"
#include "xorp.h"
#include "exceptions.hh"
class IPvX;
struct in_addr;
/**
* @short IPv4 address class
*
* The IPv4 address class is a trivial class for handling IPv4
* addresses and for performing operations on them such as printing
* and masking.
*/
class IPv4 {
public:
/**
* Default constrictor
*
* The address value is initialized to INADDR_ANY.
*/
IPv4() { _addr = 0; }
/**
* Constructor from another IPv4 address.
*
* @param ipv4 the IPv4 address to assign the address value from.
*/
IPv4(const IPv4& ipv4) : _addr(ipv4._addr) {}
/**
* Constructor from an integer value.
*
* @param value 32-bit unsigned integer to assign to the address.
*/
IPv4(uint32_t value) { _addr = value; }
/**
* Constructor from a (uint8_t *) memory pointer.
*
* @param from_uint8 the pointer to the memory to copy the address value
* from.
*/
IPv4(const uint8_t *from_uint8);
/**
* Constructor from in_addr structure.
*
* @param from_in_addr the storage to copy the address value from.
*/
IPv4(const in_addr& from_in_addr);
/**
* Constructor from sockaddr structure.
*
* @param sa sockaddr to construct IPv4 addr from.
*/
IPv4(const sockaddr& sa) throw (InvalidFamily);
/**
* Constructor from sockaddr_in structure.
*
* @param sin sockaddr_in to construct IPv4 addr from.
*/
IPv4(const sockaddr_in& sin) throw (InvalidFamily);
/**
* Constructor from a string.
*
* @param from_cstring C-style string in the IPv4 dotted decimal
* human-readable format used for initialization.
*/
IPv4(const char *from_string) throw (InvalidString);
/**
* Bitwise-Negation Operator
*
* @return address complement (i.e., all 0s become 1s, and vice-versa).
*/
inline IPv4 operator~() const { return IPv4(~_addr); }
/**
* OR Operator
*
* @param other the right-hand operand to OR with.
* @return bitwise OR of two addresses.
*/
inline IPv4 operator|(const IPv4& other) const {
return IPv4((uint32_t)(_addr | other._addr));
}
/**
* AND Operator
*
* @param other the right-hand operand to AND with.
* @return bitwise AND of two addresses.
*/
inline IPv4 operator&(const IPv4& other) const {
return IPv4((uint32_t)(_addr & other._addr));
}
/**
* XOR Operator
*
* @return eXclusive-OR of two addresses.
*/
inline IPv4 operator^(const IPv4& other) const {
return IPv4((uint32_t)(_addr ^ other._addr));
}
/**
* Operator <<
*
* @param left_shift the number of bits to shift to the left.
* @return IPv4 address that is shift bitwise to the left.
*/
IPv4 operator<<(size_t left_shift) const;
/**
* Operator >>
*
* @param right_shift the number of bits to shift to the right.
* @return IPv4 address that is shift bitwise to the right.
*/
IPv4 operator>>(size_t right_shift) const;
/**
* Less-Than Operator
*
* @param other the right-hand operand to compare against.
* @return true if the left-hand operand is numerically smaller than the
* right-hand operand.
*/
bool operator<(const IPv4& other) const;
/**
* Equality Operator
*
* @param other the right-hand operand to compare against.
* @return true if the left-hand operand is numerically same as the
* right-hand operand.
*/
bool operator==(const IPv4& other) const { return (_addr == other._addr); }
/**
* Not-Equal Operator
*
* @param other the right-hand operand to compare against.
* @return true if the left-hand operand is numerically not same as the
* right-hand operand.
*/
bool operator!=(const IPv4& other) const { return (_addr != other._addr); }
/**
* Decrement Operator
*
* The numerical value of this address is decremented by one.
* However, if the address value before the decrement was all-0s,
* after the decrement its value would be all-1s (i.e., it will
* wrap-around).
*
* @return a reference to this address after it was decremented by one.
*/
IPv4& operator--();
/**
* Increment Operator
*
* The numerical value of this address is incremented by one.
* However, if the address value before the increment was all-1s,
* after the increment its value would be all-0s (i.e., it will
* wrap-around).
*
* @return a reference to this address after it was incremented by one.
*/
IPv4& operator++();
/**
* Convert this address from binary form to presentation format.
*
* @return C++ string with the human-readable ASCII representation
* of the address.
*/
string str() const;
/**
* Test if this address is numerically zero.
*
* @return true if the address is numerically zero.
*/
bool is_zero() const { return (_addr == 0); }
/**
* Test if this address is a valid unicast address.
*
* @return true if the address is a valid unicast address.
*/
bool is_unicast() const;
/**
* Test if this address is a valid multicast address.
*
* @return true if the address is a valid multicast address.
*/
bool is_multicast() const;
/**
* Test if this address is a valid node-local multicast address.
*
* @return true if the address is a valid multicast address,
* and the scope of the address is node-local.
* XXX: in IPv4 there is no node-local multicast scope, therefore
* the return value is always false.
*/
bool is_nodelocal_multicast() const;
/**
* Test if this address is a valid link-local multicast address.
*
* @return true if the address is a valid multicast address,
* and the scope of the address is link-local.
*/
bool is_linklocal_multicast() const;
/**
* Get the address octet-size.
*
* Note that this is a static function and can be used without
* a particular object. Example:
* size_t my_size = IPv4::addr_size(); OK
* size_t my_size = ipv4.addr_size(); OK
*
* @return address size in number of octets.
*/
inline static size_t addr_size() {
static_assert(sizeof(IPv4) == sizeof(uint32_t));
return sizeof(IPv4);
}
/**
* Get the address bit-length.
*
* Note that this is a static function and can be used without
* a particular object. Example:
* size_t my_bitlen = IPv4::addr_bitlen(); OK
* size_t my_bitlen = ipv4.addr_bitlen(); OK
*
* @return address size in number of bits.
*/
inline static size_t addr_bitlen() {
return 8 * sizeof(uint8_t) * addr_size();
}
/**
* Get the masklen for the multicast base address.
*
* Note that this is a static function and can be used without
* a particular object. Example:
* size_t my_len = IPv4::ip_multicast_base_address_masklen(); OK
* size_t my_len = ipv4.ip_multicast_base_address_masklen(); OK
*
* @return the multicast base address masklen for family AF_INET.
*/
static size_t ip_multicast_base_address_masklen() {
#define IP_MULTICAST_BASE_ADDRESS_MASKLEN_IPV4 4
return (IP_MULTICAST_BASE_ADDRESS_MASKLEN_IPV4);
#undef IP_MULTICAST_BASE_ADDRESS_MASKLEN_IPV4
}
/**
* Make an IPv4 mask prefix.
*
* @param masklen the length of the mask to create.
* @return a new IPv4 address that contains a mask of length @ref masklen.
*/
static IPv4 make_prefix(size_t masklen);
/**
* Make an IPv4 address prefix.
*
* @param masklen the length of the mask of the prefix to create.
* @return a new IPv4 address created by masking this address with a mask
* of length @ref masklen.
*/
inline IPv4 mask_by_prefix(size_t masklen) const {
return (*this) & make_prefix(masklen);
}
/**
* Get the mask length.
*
* @return the prefix length of the contiguous mask presumably stored
* as an IPv4 address.
*/
size_t prefix_length() const;
/**
* Get the uint32_t raw value of this address.
*
* @return the value of this IPv4 address as an unsigned 32-bit integer.
*/
uint32_t addr() const { return _addr; }
/**
* Set the address value.
*
* @param value unsigned 32-bit integer value to set the address to.
*/
void set_addr(uint32_t value) { _addr = value; }
/**
* Constant for address family
*/
enum { AF = AF_INET };
/**
* Constant for IP protocol version
*/
enum { IPV = 4 };
/**
* Get the address family.
*
* @return the address family of this address.
*/
inline static const uint32_t af() { return AF; }
/**
* Get the IP protocol version.
*
* @return the IP protocol version of this address.
*/
inline static const uint32_t ip_version() { return IPV; }
/**
* Extract bits from an address.
*
* @param lsb starting bit position (from the right) to extract.
* @param len number of bits to extract. The maximum value is 32.
* @return the first @ref len bits starting from the rightmost
* position @ref lsb. The returned bits are in host order.
*/
inline uint32_t bits(size_t lsb, size_t len) const;
/**
* Pre-defined IPv4 address constants.
*/
inline static IPv4 ZERO(int af = AF_INET);
inline static IPv4 ANY(int af = AF_INET);
inline static IPv4 ALL_ONES(int af = AF_INET);
inline static IPv4 MULTICAST_BASE(int af = AF_INET);
inline static IPv4 MULTICAST_ALL_SYSTEMS(int af = AF_INET);
inline static IPv4 MULTICAST_ALL_ROUTERS(int af = AF_INET);
inline static IPv4 DVMRP_ROUTERS(int af = AF_INET);
inline static IPv4 OSPFIGP_ROUTERS(int af = AF_INET);
inline static IPv4 OSPFIGP_DESIGNATED_ROUTERS(int af = AF_INET);
inline static IPv4 RIP2_ROUTERS(int af = AF_INET);
inline static IPv4 PIM_ROUTERS(int af = AF_INET);
private:
uint32_t _addr; // The address value (in network-order)
};
//
// Micro-optimization: byte ordering fix for constants. htonl uses
// CPU instructions, whereas the macro below can be handled by the
// compiler front-end for literal values.
//
#if defined(WORDS_BIGENDIAN)
# define htonl_literal(x) (x)
#elif defined(WORDS_SMALLENDIAN)
# define htonl_literal(x) \
((((x) & 0x000000ffU) << 24) | (((x) & 0x0000ff00U) << 8) | \
(((x) & 0x00ff0000U) >> 8) | (((x) & 0xff000000U) >> 24))
#else
# error "Missing endian definition from config.h"
#endif
inline uint32_t
IPv4::bits(size_t lsb, size_t len) const
{
uint32_t mask = ~(0xffffffffU << len);
if (len >= 32)
mask = 0xffffffffU; // XXX: shifting with >= 32 bits is undefined
return (ntohl(_addr) >> lsb) & mask;
}
IPv4 IPv4::ZERO(int) {
return IPv4(0x0U);
}
IPv4 IPv4::ANY(int) {
return ZERO();
}
IPv4 IPv4::ALL_ONES(int) {
return IPv4(0xffffffffU);
}
IPv4 IPv4::MULTICAST_BASE(int) {
return IPv4(htonl_literal(0xe0000000U));
}
IPv4 IPv4::MULTICAST_ALL_SYSTEMS(int) {
return IPv4(htonl_literal(0xe0000001U));
}
IPv4 IPv4::MULTICAST_ALL_ROUTERS(int) {
return IPv4(htonl_literal(0xe0000002U));
}
IPv4 IPv4::DVMRP_ROUTERS(int) {
return IPv4(htonl_literal(0xe0000004U));
}
IPv4 IPv4::OSPFIGP_ROUTERS(int) {
return IPv4(htonl_literal(0xe0000005U));
}
IPv4 IPv4::OSPFIGP_DESIGNATED_ROUTERS(int) {
return IPv4(htonl_literal(0xe0000006U));
}
IPv4 IPv4::RIP2_ROUTERS(int) {
return IPv4(htonl_literal(0xe0000009U));
}
IPv4 IPv4::PIM_ROUTERS(int) {
return IPv4(htonl_literal(0xe000000dU));
}
#endif // __LIBXORP_IPV4_HH__
| Generated by: pavlin on possum.icir.org on Wed Dec 11 16:50:31 2002, using kdoc 2.0a54+XORP. |
