Jonathan Hart

Created IpAddress class

package org.onlab.packet;
import java.util.Arrays;
/**
* A class representing an IPv4 address.
* <p/>
* TODO this class is a clone of IpPrefix and still needs to be modified to
* look more like an IpAddress.
*/
public final class IpAddress {
// TODO a comparator for netmasks? E.g. for sorting by prefix match order.
//IP Versions
public enum Version { INET, INET6 };
//lengths of address, in bytes
public static final int INET_LEN = 4;
public static final int INET6_LEN = 16;
//maximum CIDR value
public static final int MAX_INET_MASK = 32;
//no mask (no network), e.g. a simple address
public static final int DEFAULT_MASK = 0;
/**
* Default value indicating an unspecified address.
*/
static final byte[] ANY = new byte [] {0, 0, 0, 0};
protected Version version;
protected byte[] octets;
protected int netmask;
private IpAddress(Version ver, byte[] octets, int netmask) {
this.version = ver;
this.octets = Arrays.copyOf(octets, INET_LEN);
this.netmask = netmask;
}
private IpAddress(Version ver, byte[] octets) {
this.version = ver;
this.octets = Arrays.copyOf(octets, INET_LEN);
this.netmask = DEFAULT_MASK;
}
/**
* Converts a byte array into an IP address.
*
* @param address a byte array
* @return an IP address
*/
public static IpAddress valueOf(byte [] address) {
return new IpAddress(Version.INET, address);
}
/**
* Converts a byte array into an IP address.
*
* @param address a byte array
* @param netmask the CIDR value subnet mask
* @return an IP address
*/
public static IpAddress valueOf(byte [] address, int netmask) {
return new IpAddress(Version.INET, address, netmask);
}
/**
* Helper to convert an integer into a byte array.
*
* @param address the integer to convert
* @return a byte array
*/
private static byte [] bytes(int address) {
byte [] bytes = new byte [INET_LEN];
for (int i = 0; i < INET_LEN; i++) {
bytes[i] = (byte) ((address >> (INET_LEN - (i + 1)) * 8) & 0xff);
}
return bytes;
}
/**
* Converts an integer into an IPv4 address.
*
* @param address an integer representing an IP value
* @return an IP address
*/
public static IpAddress valueOf(int address) {
return new IpAddress(Version.INET, bytes(address));
}
/**
* Converts an integer into an IPv4 address.
*
* @param address an integer representing an IP value
* @param netmask the CIDR value subnet mask
* @return an IP address
*/
public static IpAddress valueOf(int address, int netmask) {
return new IpAddress(Version.INET, bytes(address), netmask);
}
/**
* Converts a dotted-decimal string (x.x.x.x) into an IPv4 address. The
* string can also be in CIDR (slash) notation. If the netmask is omitted,
* it will be set to DEFAULT_MASK (0).
*
* @param address a IP address in string form, e.g. "10.0.0.1", "10.0.0.1/24"
* @return an IP address
*/
public static IpAddress valueOf(String address) {
final String [] parts = address.split("\\/");
if (parts.length > 2) {
throw new IllegalArgumentException("Malformed IP address string; "
+ "Address must take form \"x.x.x.x\" or \"x.x.x.x/y\"");
}
int mask = DEFAULT_MASK;
if (parts.length == 2) {
mask = Integer.valueOf(parts[1]);
if (mask > MAX_INET_MASK) {
throw new IllegalArgumentException(
"Value of subnet mask cannot exceed "
+ MAX_INET_MASK);
}
}
final String [] net = parts[0].split("\\.");
if (net.length != INET_LEN) {
throw new IllegalArgumentException("Malformed IP address string; "
+ "Address must have four decimal values separated by dots (.)");
}
final byte [] bytes = new byte[INET_LEN];
for (int i = 0; i < INET_LEN; i++) {
bytes[i] = (byte) Short.parseShort(net[i], 10);
}
return new IpAddress(Version.INET, bytes, mask);
}
/**
* Returns the IP version of this address.
*
* @return the version
*/
public Version version() {
return this.version;
}
/**
* Returns the IP address as a byte array.
*
* @return a byte array
*/
public byte[] toOctets() {
return Arrays.copyOf(this.octets, INET_LEN);
}
/**
* Returns the IP address prefix length.
*
* @return prefix length
*/
public int prefixLength() {
return netmask;
}
/**
* Returns the integral value of this IP address.
*
* @return the IP address's value as an integer
*/
public int toInt() {
int address = 0;
for (int i = 0; i < INET_LEN; i++) {
address |= octets[i] << ((INET_LEN - (i + 1)) * 8);
}
return address;
}
/**
* Helper for computing the mask value from CIDR.
*
* @return an integer bitmask
*/
private int mask() {
int shift = MAX_INET_MASK - this.netmask;
return ((Integer.MAX_VALUE >>> (shift - 1)) << shift);
}
/**
* Returns the subnet mask in IpAddress form. The netmask value for
* the returned IpAddress is 0, as the address itself is a mask.
*
* @return the subnet mask
*/
public IpAddress netmask() {
return new IpAddress(Version.INET, bytes(mask()));
}
/**
* Returns the network portion of this address as an IpAddress.
* The netmask of the returned IpAddress is the current mask. If this
* address doesn't have a mask, this returns an all-0 IpAddress.
*
* @return the network address or null
*/
public IpAddress network() {
if (netmask == DEFAULT_MASK) {
return new IpAddress(version, ANY, DEFAULT_MASK);
}
byte [] net = new byte [4];
byte [] mask = bytes(mask());
for (int i = 0; i < INET_LEN; i++) {
net[i] = (byte) (octets[i] & mask[i]);
}
return new IpAddress(version, net, netmask);
}
/**
* Returns the host portion of the IPAddress, as an IPAddress.
* The netmask of the returned IpAddress is the current mask. If this
* address doesn't have a mask, this returns a copy of the current
* address.
*
* @return the host address
*/
public IpAddress host() {
if (netmask == DEFAULT_MASK) {
new IpAddress(version, octets, netmask);
}
byte [] host = new byte [INET_LEN];
byte [] mask = bytes(mask());
for (int i = 0; i < INET_LEN; i++) {
host[i] = (byte) (octets[i] & ~mask[i]);
}
return new IpAddress(version, host, netmask);
}
public boolean isMasked() {
return mask() != 0;
}
/**
* Determines whether a given address is contained within this IpAddress'
* network.
*
* @param other another IP address that could be contained in this network
* @return true if the other IP address is contained in this address'
* network, otherwise false
*/
public boolean contains(IpAddress other) {
if (this.netmask <= other.netmask) {
// Special case where they're both /32 addresses
if (this.netmask == MAX_INET_MASK) {
return Arrays.equals(octets, other.octets);
}
// Mask the other address with our network mask
IpAddress otherMasked =
IpAddress.valueOf(other.octets, netmask).network();
return network().equals(otherMasked);
}
return false;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + netmask;
result = prime * result + Arrays.hashCode(octets);
result = prime * result + ((version == null) ? 0 : version.hashCode());
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
IpAddress other = (IpAddress) obj;
if (netmask != other.netmask) {
return false;
}
if (!Arrays.equals(octets, other.octets)) {
return false;
}
if (version != other.version) {
return false;
}
return true;
}
@Override
/*
* (non-Javadoc)
* format is "x.x.x.x" for non-masked (netmask 0) addresses,
* and "x.x.x.x/y" for masked addresses.
*
* @see java.lang.Object#toString()
*/
public String toString() {
final StringBuilder builder = new StringBuilder();
for (final byte b : this.octets) {
if (builder.length() > 0) {
builder.append(".");
}
builder.append(String.format("%d", b & 0xff));
}
if (netmask != DEFAULT_MASK) {
builder.append("/");
builder.append(String.format("%d", netmask));
}
return builder.toString();
}
}
......@@ -3,7 +3,9 @@ package org.onlab.packet;
import java.util.Arrays;
/**
* A class representing an IPv4 address.
* A class representing an IPv4 prefix.
* <p/>
* A prefix consists of an IP address and a subnet mask.
*/
public final class IpPrefix {
......