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Camel Netty NIO based socket communication component
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.camel.component.netty.util;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* A class that performs some subnet calculations given a network address and a subnet mask.
*
* @see "http://www.faqs.org/rfcs/rfc1519.html" This class is copied from apache common net
*/
public class SubnetUtils {
private static final String IP_ADDRESS = "(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})";
private static final String SLASH_FORMAT = IP_ADDRESS + "/(\\d{1,3})";
private static final Pattern ADDRESS_PATTERN = Pattern.compile(IP_ADDRESS);
private static final Pattern CIDR_PATTERN = Pattern.compile(SLASH_FORMAT);
private static final int NBITS = 32;
private int netmask;
private int address;
private int network;
private int broadcast;
/** Whether the broadcast/network address are included in host count */
private boolean inclusiveHostCount;
/**
* Constructor that takes a CIDR-notation string, e.g. "192.168.0.1/16"
*
* @param cidrNotation A CIDR-notation string, e.g. "192.168.0.1/16"
* @throws IllegalArgumentException if the parameter is invalid, i.e. does not match n.n.n.n/m where n=1-3 decimal
* digits, m = 1-3 decimal digits in range 1-32
*/
public SubnetUtils(String cidrNotation) {
calculate(cidrNotation);
}
/**
* Constructor that takes a dotted decimal address and a dotted decimal mask.
*
* @param address An IP address, e.g. "192.168.0.1"
* @param mask A dotted decimal netmask e.g. "255.255.0.0"
* @throws IllegalArgumentException if the address or mask is invalid, i.e. does not match n.n.n.n where n=1-3
* decimal digits and the mask is not all zeros
*/
public SubnetUtils(String address, String mask) {
calculate(toCidrNotation(address, mask));
}
/**
* Returns true if the return value of {@link SubnetInfo#getAddressCount()} includes the network and
* broadcast addresses.
*
* @since 2.2
* @return true if the hostcount includes the network and broadcast addresses
*/
public boolean isInclusiveHostCount() {
return inclusiveHostCount;
}
/**
* Set to true if you want the return value of {@link SubnetInfo#getAddressCount()} to include the
* network and broadcast addresses.
*
* @param inclusiveHostCount true if network and broadcast addresses are to be included
* @since 2.2
*/
public void setInclusiveHostCount(boolean inclusiveHostCount) {
this.inclusiveHostCount = inclusiveHostCount;
}
/**
* Convenience container for subnet summary information.
*
*/
public final class SubnetInfo {
/* Mask to convert unsigned int to a long (i.e. keep 32 bits) */
private static final long UNSIGNED_INT_MASK = 0x0FFFFFFFFL;
private SubnetInfo() {
}
private int netmask() {
return netmask;
}
private int network() {
return network;
}
private int address() {
return address;
}
private int broadcast() {
return broadcast;
}
// long versions of the values (as unsigned int) which are more suitable for range checking
private long networkLong() {
return network & UNSIGNED_INT_MASK;
}
private long broadcastLong() {
return broadcast & UNSIGNED_INT_MASK;
}
private int low() {
return isInclusiveHostCount() ? network()
: broadcastLong() - networkLong() > 1 ? network() + 1 : 0;
}
private int high() {
return isInclusiveHostCount() ? broadcast()
: broadcastLong() - networkLong() > 1 ? broadcast() - 1 : 0;
}
/**
* Returns true if the parameter address is in the range of usable endpoint addresses for this
* subnet. This excludes the network and broadcast adresses.
*
* @param address A dot-delimited IPv4 address, e.g. "192.168.0.1"
* @return True if in range, false otherwise
*/
public boolean isInRange(String address) {
Matcher matcher = ADDRESS_PATTERN.matcher(address);
if (matcher.matches()) {
return isInRange(toInteger(address));
} else {
return false;
}
}
private boolean isInRange(int address) {
long addLong = address & UNSIGNED_INT_MASK;
long lowLong = low() & UNSIGNED_INT_MASK;
long highLong = high() & UNSIGNED_INT_MASK;
return addLong >= lowLong && addLong <= highLong;
}
public String getBroadcastAddress() {
return format(toArray(broadcast()));
}
public String getNetworkAddress() {
return format(toArray(network()));
}
public String getNetmask() {
return format(toArray(netmask()));
}
public String getAddress() {
return format(toArray(address()));
}
/**
* Return the low address as a dotted IP address. Will be zero for CIDR/31 and CIDR/32 if the inclusive flag is
* false.
*
* @return the IP address in dotted format, may be "0.0.0.0" if there is no valid address
*/
public String getLowAddress() {
return format(toArray(low()));
}
/**
* Return the high address as a dotted IP address. Will be zero for CIDR/31 and CIDR/32 if the inclusive flag is
* false.
*
* @return the IP address in dotted format, may be "0.0.0.0" if there is no valid address
*/
public String getHighAddress() {
return format(toArray(high()));
}
/**
* Get the count of available addresses. Will be zero for CIDR/31 and CIDR/32 if the inclusive flag is false.
*
* @return the count of addresses, may be zero.
* @throws RuntimeException if the correct count is greater than {@code Integer.MAX_VALUE}
* @deprecated use {@link #getAddressCountLong()} instead
*/
@Deprecated
public int getAddressCount() {
long countLong = getAddressCountLong();
if (countLong > Integer.MAX_VALUE) {
throw new RuntimeException("Count is larger than an integer: " + countLong);
}
// N.B. cannot be negative
return (int) countLong;
}
/**
* Get the count of available addresses. Will be zero for CIDR/31 and CIDR/32 if the inclusive flag is false.
*
* @return the count of addresses, may be zero.
*/
public long getAddressCountLong() {
long b = broadcastLong();
long n = networkLong();
long count = b - n + (isInclusiveHostCount() ? 1 : -1);
return count < 0 ? 0 : count;
}
public int asInteger(String address) {
return toInteger(address);
}
public String getCidrSignature() {
return toCidrNotation(
format(toArray(address())),
format(toArray(netmask())));
}
public String[] getAllAddresses() {
int ct = getAddressCount();
String[] addresses = new String[ct];
if (ct == 0) {
return addresses;
}
int j = 0;
for (int add = low(); add <= high(); ++add) {
addresses[j] = format(toArray(add));
++j;
}
return addresses;
}
/**
* {@inheritDoc}
*
* @since 2.2
*/
@Override
public String toString() {
final StringBuilder buf = new StringBuilder();
buf.append("CIDR Signature:\t[").append(getCidrSignature()).append("]")
.append(" Netmask: [").append(getNetmask()).append("]\n")
.append("Network:\t[").append(getNetworkAddress()).append("]\n")
.append("Broadcast:\t[").append(getBroadcastAddress()).append("]\n")
.append("First Address:\t[").append(getLowAddress()).append("]\n")
.append("Last Address:\t[").append(getHighAddress()).append("]\n")
.append("# Addresses:\t[").append(getAddressCount()).append("]\n");
return buf.toString();
}
}
/**
* Return a {@link SubnetInfo} instance that contains subnet-specific statistics
*
* @return new instance
*/
public final SubnetInfo getInfo() {
return new SubnetInfo();
}
/*
* Initialize the internal fields from the supplied CIDR mask
*/
private void calculate(String mask) {
Matcher matcher = CIDR_PATTERN.matcher(mask);
if (matcher.matches()) {
address = matchAddress(matcher);
/* Create a binary netmask from the number of bits specification /x */
int cidrPart = rangeCheck(Integer.parseInt(matcher.group(5)), 0, NBITS);
for (int j = 0; j < cidrPart; ++j) {
netmask |= 1 << 31 - j;
}
/* Calculate base network address */
network = address & netmask;
/* Calculate broadcast address */
broadcast = network | ~netmask;
} else {
throw new IllegalArgumentException("Could not parse [" + mask + "]");
}
}
/*
* Convert a dotted decimal format address to a packed integer format
*/
private int toInteger(String address) {
Matcher matcher = ADDRESS_PATTERN.matcher(address);
if (matcher.matches()) {
return matchAddress(matcher);
} else {
throw new IllegalArgumentException("Could not parse [" + address + "]");
}
}
/*
* Convenience method to extract the components of a dotted decimal address and
* pack into an integer using a regex match
*/
private int matchAddress(Matcher matcher) {
int addr = 0;
for (int i = 1; i <= 4; ++i) {
int n = rangeCheck(Integer.parseInt(matcher.group(i)), 0, 255);
addr |= (n & 0xff) << 8 * (4 - i);
}
return addr;
}
/*
* Convert a packed integer address into a 4-element array
*/
private int[] toArray(int val) {
int[] ret = new int[4];
for (int j = 3; j >= 0; --j) {
ret[j] |= (val >>> 8 * (3 - j)) & 0xff;
}
return ret;
}
/*
* Convert a 4-element array into dotted decimal format
*/
private String format(int[] octets) {
StringBuilder str = new StringBuilder();
for (int i = 0; i < octets.length; ++i) {
str.append(octets[i]);
if (i != octets.length - 1) {
str.append(".");
}
}
return str.toString();
}
/*
* Convenience function to check integer boundaries.
* Checks if a value x is in the range [begin,end].
* Returns x if it is in range, throws an exception otherwise.
*/
private int rangeCheck(int value, int begin, int end) {
if (value >= begin && value <= end) { // (begin,end]
return value;
}
throw new IllegalArgumentException("Value [" + value + "] not in range [" + begin + "," + end + "]");
}
/*
* Count the number of 1-bits in a 32-bit integer using a divide-and-conquer strategy
* see Hacker's Delight section 5.1
*/
int pop(int x) {
x = x - ((x >>> 1) & 0x55555555);
x = (x & 0x33333333) + ((x >>> 2) & 0x33333333);
x = (x + (x >>> 4)) & 0x0F0F0F0F;
x = x + (x >>> 8);
x = x + (x >>> 16);
return x & 0x0000003F;
}
/* Convert two dotted decimal addresses to a single xxx.xxx.xxx.xxx/yy format
* by counting the 1-bit population in the mask address. (It may be better to count
* NBITS-#trailing zeroes for this case)
*/
private String toCidrNotation(String addr, String mask) {
return addr + "/" + pop(toInteger(mask));
}
}
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