Add utils to convert Inet4Address <-> int
The current utilities map the higher-order bytes of ints to the
lower-order bytes of IPv4 addresses, which makes applying masks and
generating series of addresses confusing.
For example, the current utilities would convert 1.2.3.4 to 0x04030201,
or generate 0x0080ffff for a /17 subnet mask. The utilities in this CL
convert 1.2.3.4 to 0x01020304, and a /17 subnet mask is represented as
0xffff8000.
Includes tests for all the above methods and migration of
NetworkUtilsTest to JUnit4.
Test: added tests pass
Change-Id: I5f5aa2e6e3b054b66b9dc507dab64f41be9139b1
diff --git a/core/java/android/net/NetworkUtils.java b/core/java/android/net/NetworkUtils.java
index 9a5d502..dc1f805 100644
--- a/core/java/android/net/NetworkUtils.java
+++ b/core/java/android/net/NetworkUtils.java
@@ -126,51 +126,122 @@
public native static boolean queryUserAccess(int uid, int netId);
/**
- * Convert a IPv4 address from an integer to an InetAddress.
- * @param hostAddress an int corresponding to the IPv4 address in network byte order
+ * @see #intToInet4AddressHTL(int)
+ * @deprecated Use either {@link #intToInet4AddressHTH(int)}
+ * or {@link #intToInet4AddressHTL(int)}
*/
+ @Deprecated
public static InetAddress intToInetAddress(int hostAddress) {
- byte[] addressBytes = { (byte)(0xff & hostAddress),
- (byte)(0xff & (hostAddress >> 8)),
- (byte)(0xff & (hostAddress >> 16)),
- (byte)(0xff & (hostAddress >> 24)) };
+ return intToInet4AddressHTL(hostAddress);
+ }
+
+ /**
+ * Convert a IPv4 address from an integer to an InetAddress (0x04030201 -> 1.2.3.4)
+ *
+ * <p>This method uses the higher-order int bytes as the lower-order IPv4 address bytes,
+ * which is an unusual convention. Consider {@link #intToInet4AddressHTH(int)} instead.
+ * @param hostAddress an int coding for an IPv4 address, where higher-order int byte is
+ * lower-order IPv4 address byte
+ */
+ public static InetAddress intToInet4AddressHTL(int hostAddress) {
+ return intToInet4AddressHTH(Integer.reverseBytes(hostAddress));
+ }
+
+ /**
+ * Convert a IPv4 address from an integer to an InetAddress (0x01020304 -> 1.2.3.4)
+ * @param hostAddress an int coding for an IPv4 address
+ */
+ public static InetAddress intToInet4AddressHTH(int hostAddress) {
+ byte[] addressBytes = { (byte) (0xff & (hostAddress >> 24)),
+ (byte) (0xff & (hostAddress >> 16)),
+ (byte) (0xff & (hostAddress >> 8)),
+ (byte) (0xff & hostAddress) };
try {
- return InetAddress.getByAddress(addressBytes);
+ return InetAddress.getByAddress(addressBytes);
} catch (UnknownHostException e) {
- throw new AssertionError();
+ throw new AssertionError();
}
}
/**
- * Convert a IPv4 address from an InetAddress to an integer
- * @param inetAddr is an InetAddress corresponding to the IPv4 address
- * @return the IP address as an integer in network byte order
+ * @see #inet4AddressToIntHTL(Inet4Address)
+ * @deprecated Use either {@link #inet4AddressToIntHTH(Inet4Address)}
+ * or {@link #inet4AddressToIntHTL(Inet4Address)}
*/
+ @Deprecated
public static int inetAddressToInt(Inet4Address inetAddr)
throws IllegalArgumentException {
- byte [] addr = inetAddr.getAddress();
- return ((addr[3] & 0xff) << 24) | ((addr[2] & 0xff) << 16) |
- ((addr[1] & 0xff) << 8) | (addr[0] & 0xff);
+ return inet4AddressToIntHTL(inetAddr);
}
/**
- * Convert a network prefix length to an IPv4 netmask integer
- * @param prefixLength
- * @return the IPv4 netmask as an integer in network byte order
+ * Convert an IPv4 address from an InetAddress to an integer (1.2.3.4 -> 0x01020304)
+ *
+ * <p>This conversion can help order IP addresses: considering the ordering
+ * 192.0.2.1 < 192.0.2.2 < ..., resulting ints will follow that ordering if read as unsigned
+ * integers with {@link Integer#toUnsignedLong}.
+ * @param inetAddr is an InetAddress corresponding to the IPv4 address
+ * @return the IP address as integer
*/
+ public static int inet4AddressToIntHTH(Inet4Address inetAddr)
+ throws IllegalArgumentException {
+ byte [] addr = inetAddr.getAddress();
+ return ((addr[0] & 0xff) << 24) | ((addr[1] & 0xff) << 16)
+ | ((addr[2] & 0xff) << 8) | (addr[3] & 0xff);
+ }
+
+ /**
+ * Convert a IPv4 address from an InetAddress to an integer (1.2.3.4 -> 0x04030201)
+ *
+ * <p>This method stores the higher-order IPv4 address bytes in the lower-order int bytes,
+ * which is an unusual convention. Consider {@link #inet4AddressToIntHTH(Inet4Address)} instead.
+ * @param inetAddr is an InetAddress corresponding to the IPv4 address
+ * @return the IP address as integer
+ */
+ public static int inet4AddressToIntHTL(Inet4Address inetAddr) {
+ return Integer.reverseBytes(inet4AddressToIntHTH(inetAddr));
+ }
+
+ /**
+ * @see #prefixLengthToV4NetmaskIntHTL(int)
+ * @deprecated Use either {@link #prefixLengthToV4NetmaskIntHTH(int)}
+ * or {@link #prefixLengthToV4NetmaskIntHTL(int)}
+ */
+ @Deprecated
public static int prefixLengthToNetmaskInt(int prefixLength)
throws IllegalArgumentException {
+ return prefixLengthToV4NetmaskIntHTL(prefixLength);
+ }
+
+ /**
+ * Convert a network prefix length to an IPv4 netmask integer (prefixLength 17 -> 0xffff8000)
+ * @return the IPv4 netmask as an integer
+ */
+ public static int prefixLengthToV4NetmaskIntHTH(int prefixLength)
+ throws IllegalArgumentException {
if (prefixLength < 0 || prefixLength > 32) {
throw new IllegalArgumentException("Invalid prefix length (0 <= prefix <= 32)");
}
- int value = 0xffffffff << (32 - prefixLength);
- return Integer.reverseBytes(value);
+ // (int)a << b is equivalent to a << (b & 0x1f): can't shift by 32 (-1 << 32 == -1)
+ return prefixLength == 0 ? 0 : 0xffffffff << (32 - prefixLength);
+ }
+
+ /**
+ * Convert a network prefix length to an IPv4 netmask integer (prefixLength 17 -> 0x0080ffff).
+ *
+ * <p>This method stores the higher-order IPv4 address bytes in the lower-order int bytes,
+ * which is an unusual convention. Consider {@link #prefixLengthToV4NetmaskIntHTH(int)} instead.
+ * @return the IPv4 netmask as an integer
+ */
+ public static int prefixLengthToV4NetmaskIntHTL(int prefixLength)
+ throws IllegalArgumentException {
+ return Integer.reverseBytes(prefixLengthToV4NetmaskIntHTH(prefixLength));
}
/**
* Convert a IPv4 netmask integer to a prefix length
- * @param netmask as an integer in network byte order
+ * @param netmask as an integer (0xff000000 for a /8 subnet)
* @return the network prefix length
*/
public static int netmaskIntToPrefixLength(int netmask) {
diff --git a/tests/net/java/android/net/NetworkUtilsTest.java b/tests/net/java/android/net/NetworkUtilsTest.java
index a5ee8e3..2b172da 100644
--- a/tests/net/java/android/net/NetworkUtilsTest.java
+++ b/tests/net/java/android/net/NetworkUtilsTest.java
@@ -16,17 +16,32 @@
package android.net;
-import android.net.NetworkUtils;
-import android.test.suitebuilder.annotation.SmallTest;
+import static android.net.NetworkUtils.getImplicitNetmask;
+import static android.net.NetworkUtils.inet4AddressToIntHTH;
+import static android.net.NetworkUtils.inet4AddressToIntHTL;
+import static android.net.NetworkUtils.intToInet4AddressHTH;
+import static android.net.NetworkUtils.intToInet4AddressHTL;
+import static android.net.NetworkUtils.netmaskToPrefixLength;
+import static android.net.NetworkUtils.prefixLengthToV4NetmaskIntHTH;
+import static android.net.NetworkUtils.prefixLengthToV4NetmaskIntHTL;
+
+import static junit.framework.Assert.assertEquals;
+
+import static org.junit.Assert.fail;
+
+import android.support.test.runner.AndroidJUnit4;
import java.math.BigInteger;
import java.net.Inet4Address;
import java.net.InetAddress;
import java.util.TreeSet;
-import junit.framework.TestCase;
+import org.junit.Test;
+import org.junit.runner.RunWith;
-public class NetworkUtilsTest extends TestCase {
+@RunWith(AndroidJUnit4.class)
+@android.support.test.filters.SmallTest
+public class NetworkUtilsTest {
private InetAddress Address(String addr) {
return InetAddress.parseNumericAddress(addr);
@@ -36,41 +51,126 @@
return (Inet4Address) Address(addr);
}
- @SmallTest
+ @Test
public void testGetImplicitNetmask() {
- assertEquals(8, NetworkUtils.getImplicitNetmask(IPv4Address("4.2.2.2")));
- assertEquals(8, NetworkUtils.getImplicitNetmask(IPv4Address("10.5.6.7")));
- assertEquals(16, NetworkUtils.getImplicitNetmask(IPv4Address("173.194.72.105")));
- assertEquals(16, NetworkUtils.getImplicitNetmask(IPv4Address("172.23.68.145")));
- assertEquals(24, NetworkUtils.getImplicitNetmask(IPv4Address("192.0.2.1")));
- assertEquals(24, NetworkUtils.getImplicitNetmask(IPv4Address("192.168.5.1")));
- assertEquals(32, NetworkUtils.getImplicitNetmask(IPv4Address("224.0.0.1")));
- assertEquals(32, NetworkUtils.getImplicitNetmask(IPv4Address("255.6.7.8")));
+ assertEquals(8, getImplicitNetmask(IPv4Address("4.2.2.2")));
+ assertEquals(8, getImplicitNetmask(IPv4Address("10.5.6.7")));
+ assertEquals(16, getImplicitNetmask(IPv4Address("173.194.72.105")));
+ assertEquals(16, getImplicitNetmask(IPv4Address("172.23.68.145")));
+ assertEquals(24, getImplicitNetmask(IPv4Address("192.0.2.1")));
+ assertEquals(24, getImplicitNetmask(IPv4Address("192.168.5.1")));
+ assertEquals(32, getImplicitNetmask(IPv4Address("224.0.0.1")));
+ assertEquals(32, getImplicitNetmask(IPv4Address("255.6.7.8")));
}
private void assertInvalidNetworkMask(Inet4Address addr) {
try {
- NetworkUtils.netmaskToPrefixLength(addr);
+ netmaskToPrefixLength(addr);
fail("Invalid netmask " + addr.getHostAddress() + " did not cause exception");
} catch (IllegalArgumentException expected) {
}
}
- @SmallTest
+ @Test
+ public void testInet4AddressToIntHTL() {
+ assertEquals(0, inet4AddressToIntHTL(IPv4Address("0.0.0.0")));
+ assertEquals(0x000080ff, inet4AddressToIntHTL(IPv4Address("255.128.0.0")));
+ assertEquals(0x0080ff0a, inet4AddressToIntHTL(IPv4Address("10.255.128.0")));
+ assertEquals(0x00feff0a, inet4AddressToIntHTL(IPv4Address("10.255.254.0")));
+ assertEquals(0xfeffa8c0, inet4AddressToIntHTL(IPv4Address("192.168.255.254")));
+ assertEquals(0xffffa8c0, inet4AddressToIntHTL(IPv4Address("192.168.255.255")));
+ }
+
+ @Test
+ public void testIntToInet4AddressHTL() {
+ assertEquals(IPv4Address("0.0.0.0"), intToInet4AddressHTL(0));
+ assertEquals(IPv4Address("255.128.0.0"), intToInet4AddressHTL(0x000080ff));
+ assertEquals(IPv4Address("10.255.128.0"), intToInet4AddressHTL(0x0080ff0a));
+ assertEquals(IPv4Address("10.255.254.0"), intToInet4AddressHTL(0x00feff0a));
+ assertEquals(IPv4Address("192.168.255.254"), intToInet4AddressHTL(0xfeffa8c0));
+ assertEquals(IPv4Address("192.168.255.255"), intToInet4AddressHTL(0xffffa8c0));
+ }
+
+ @Test
+ public void testInet4AddressToIntHTH() {
+ assertEquals(0, inet4AddressToIntHTH(IPv4Address("0.0.0.0")));
+ assertEquals(0xff800000, inet4AddressToIntHTH(IPv4Address("255.128.0.0")));
+ assertEquals(0x0aff8000, inet4AddressToIntHTH(IPv4Address("10.255.128.0")));
+ assertEquals(0x0afffe00, inet4AddressToIntHTH(IPv4Address("10.255.254.0")));
+ assertEquals(0xc0a8fffe, inet4AddressToIntHTH(IPv4Address("192.168.255.254")));
+ assertEquals(0xc0a8ffff, inet4AddressToIntHTH(IPv4Address("192.168.255.255")));
+ }
+
+ @Test
+ public void testIntToInet4AddressHTH() {
+ assertEquals(IPv4Address("0.0.0.0"), intToInet4AddressHTH(0));
+ assertEquals(IPv4Address("255.128.0.0"), intToInet4AddressHTH(0xff800000));
+ assertEquals(IPv4Address("10.255.128.0"), intToInet4AddressHTH(0x0aff8000));
+ assertEquals(IPv4Address("10.255.254.0"), intToInet4AddressHTH(0x0afffe00));
+ assertEquals(IPv4Address("192.168.255.254"), intToInet4AddressHTH(0xc0a8fffe));
+ assertEquals(IPv4Address("192.168.255.255"), intToInet4AddressHTH(0xc0a8ffff));
+ }
+
+ @Test
public void testNetmaskToPrefixLength() {
- assertEquals(0, NetworkUtils.netmaskToPrefixLength(IPv4Address("0.0.0.0")));
- assertEquals(9, NetworkUtils.netmaskToPrefixLength(IPv4Address("255.128.0.0")));
- assertEquals(17, NetworkUtils.netmaskToPrefixLength(IPv4Address("255.255.128.0")));
- assertEquals(23, NetworkUtils.netmaskToPrefixLength(IPv4Address("255.255.254.0")));
- assertEquals(31, NetworkUtils.netmaskToPrefixLength(IPv4Address("255.255.255.254")));
- assertEquals(32, NetworkUtils.netmaskToPrefixLength(IPv4Address("255.255.255.255")));
+ assertEquals(0, netmaskToPrefixLength(IPv4Address("0.0.0.0")));
+ assertEquals(9, netmaskToPrefixLength(IPv4Address("255.128.0.0")));
+ assertEquals(17, netmaskToPrefixLength(IPv4Address("255.255.128.0")));
+ assertEquals(23, netmaskToPrefixLength(IPv4Address("255.255.254.0")));
+ assertEquals(31, netmaskToPrefixLength(IPv4Address("255.255.255.254")));
+ assertEquals(32, netmaskToPrefixLength(IPv4Address("255.255.255.255")));
assertInvalidNetworkMask(IPv4Address("0.0.0.1"));
assertInvalidNetworkMask(IPv4Address("255.255.255.253"));
assertInvalidNetworkMask(IPv4Address("255.255.0.255"));
}
- @SmallTest
+
+ @Test
+ public void testPrefixLengthToV4NetmaskIntHTL() {
+ assertEquals(0, prefixLengthToV4NetmaskIntHTL(0));
+ assertEquals(0x000080ff /* 255.128.0.0 */, prefixLengthToV4NetmaskIntHTL(9));
+ assertEquals(0x0080ffff /* 255.255.128.0 */, prefixLengthToV4NetmaskIntHTL(17));
+ assertEquals(0x00feffff /* 255.255.254.0 */, prefixLengthToV4NetmaskIntHTL(23));
+ assertEquals(0xfeffffff /* 255.255.255.254 */, prefixLengthToV4NetmaskIntHTL(31));
+ assertEquals(0xffffffff /* 255.255.255.255 */, prefixLengthToV4NetmaskIntHTL(32));
+ }
+
+ @Test
+ public void testPrefixLengthToV4NetmaskIntHTH() {
+ assertEquals(0, prefixLengthToV4NetmaskIntHTH(0));
+ assertEquals(0xff800000 /* 255.128.0.0 */, prefixLengthToV4NetmaskIntHTH(9));
+ assertEquals(0xffff8000 /* 255.255.128.0 */, prefixLengthToV4NetmaskIntHTH(17));
+ assertEquals(0xfffffe00 /* 255.255.254.0 */, prefixLengthToV4NetmaskIntHTH(23));
+ assertEquals(0xfffffffe /* 255.255.255.254 */, prefixLengthToV4NetmaskIntHTH(31));
+ assertEquals(0xffffffff /* 255.255.255.255 */, prefixLengthToV4NetmaskIntHTH(32));
+ }
+
+ @Test(expected = IllegalArgumentException.class)
+ public void testPrefixLengthToV4NetmaskIntHTH_NegativeLength() {
+ prefixLengthToV4NetmaskIntHTH(-1);
+ }
+
+ @Test(expected = IllegalArgumentException.class)
+ public void testPrefixLengthToV4NetmaskIntHTH_LengthTooLarge() {
+ prefixLengthToV4NetmaskIntHTH(33);
+ }
+
+ private void checkAddressMasking(String expectedAddr, String addr, int prefixLength) {
+ final int prefix = prefixLengthToV4NetmaskIntHTH(prefixLength);
+ final int addrInt = inet4AddressToIntHTH(IPv4Address(addr));
+ assertEquals(IPv4Address(expectedAddr), intToInet4AddressHTH(prefix & addrInt));
+ }
+
+ @Test
+ public void testPrefixLengthToV4NetmaskIntHTH_MaskAddr() {
+ checkAddressMasking("192.168.0.0", "192.168.128.1", 16);
+ checkAddressMasking("255.240.0.0", "255.255.255.255", 12);
+ checkAddressMasking("255.255.255.255", "255.255.255.255", 32);
+ checkAddressMasking("0.0.0.0", "255.255.255.255", 0);
+ }
+
+ @Test
public void testRoutedIPv4AddressCount() {
final TreeSet<IpPrefix> set = new TreeSet<>(IpPrefix.lengthComparator());
// No routes routes to no addresses.
@@ -118,7 +218,7 @@
assertEquals(7l - 4 + 4 + 16 + 65536, NetworkUtils.routedIPv4AddressCount(set));
}
- @SmallTest
+ @Test
public void testRoutedIPv6AddressCount() {
final TreeSet<IpPrefix> set = new TreeSet<>(IpPrefix.lengthComparator());
// No routes routes to no addresses.