src/test/java/org/apache/commons/net/util/SubnetUtils6Test.java - commons-net - Git at Google

 /*
  * 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
  *
  *      https://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.commons.net.util;

 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;

 import java.math.BigInteger;
 import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.UnknownHostException;

 import org.apache.commons.net.util.SubnetUtils6.SubnetInfo;
 import org.junit.jupiter.api.Test;

 /**
  * Tests {@link SubnetUtils6}.
  */
 class SubnetUtils6Test {

     private static final BigInteger TWO = BigInteger.valueOf(2);

     @Test
     void testBasicCidr64() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1/64");
         final SubnetInfo info = utils.getInfo();

         assertEquals(64, info.getPrefixLength());
         assertEquals("2001:db8:0:0:0:0:0:1", info.getAddress());
         assertEquals("2001:db8:0:0:0:0:0:0", info.getNetworkAddress());
         assertEquals("2001:db8:0:0:ffff:ffff:ffff:ffff", info.getHighAddress());
         // 2^64 addresses
         assertEquals(TWO.pow(64), info.getAddressCount());
     }

     @Test
     void testBasicCidr128() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1/128");
         final SubnetInfo info = utils.getInfo();

         assertEquals(128, info.getPrefixLength());
         assertEquals("2001:db8:0:0:0:0:0:1", info.getNetworkAddress());
         assertEquals("2001:db8:0:0:0:0:0:1", info.getHighAddress());
         assertEquals(BigInteger.ONE, info.getAddressCount());
     }

     @Test
     void testCidr0() {
         final SubnetUtils6 utils = new SubnetUtils6("::/0");
         final SubnetInfo info = utils.getInfo();

         assertEquals(0, info.getPrefixLength());
         assertEquals("0:0:0:0:0:0:0:0", info.getNetworkAddress());
         // 2^128 addresses
         assertEquals(TWO.pow(128), info.getAddressCount());
     }

     @Test
     void testCidr48() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8:abcd::/48");
         final SubnetInfo info = utils.getInfo();

         assertEquals(48, info.getPrefixLength());
         assertEquals("2001:db8:abcd:0:0:0:0:0", info.getNetworkAddress());
         assertEquals("2001:db8:abcd:ffff:ffff:ffff:ffff:ffff", info.getHighAddress());
     }

     @Test
     void testCompressedAddress() {
         final SubnetUtils6 utils = new SubnetUtils6("fe80::1/10");
         final SubnetInfo info = utils.getInfo();

         assertEquals(10, info.getPrefixLength());
         assertTrue(info.isInRange("fe80::1"));
         assertTrue(info.isInRange("fe80::ffff"));
         assertTrue(info.isInRange("febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff"));
         assertFalse(info.isInRange("fec0::1")); // Outside /10 range
     }

     @Test
     void testConstructorWithSeparateArgs() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1", 64);
         final SubnetInfo info = utils.getInfo();

         assertEquals(64, info.getPrefixLength());
         assertEquals("2001:db8:0:0:0:0:0:0", info.getNetworkAddress());
     }

     @Test
     void testFullAddress() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:0db8:0000:0000:0000:0000:0000:0001/64");
         final SubnetInfo info = utils.getInfo();

         assertEquals(64, info.getPrefixLength());
         assertEquals("2001:db8:0:0:0:0:0:0", info.getNetworkAddress());
     }

     @Test
     void testGetCidrSignature() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1/64");
         final SubnetInfo info = utils.getInfo();

         assertEquals("2001:db8:0:0:0:0:0:1/64", info.getCidrSignature());
     }

     @Test
     void testInvalidCidr() {
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6(null));
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1"));
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1/"));
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1/129"));
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1/-1"));
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1/abc"));
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("not-an-address/64"));
     }

     @Test
     void testInvalidTwoArgConstructor() {
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1", 129));
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1", -1));
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("not-an-address", 64));
     }

     @Test
     void testInvalidIPv4Address() {
         // IPv4 addresses should be rejected
         assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("192.168.1.1/24"));
     }

     @Test
     void testIsInRange() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
         final SubnetInfo info = utils.getInfo();

         // Addresses in range
         assertTrue(info.isInRange("2001:db8::1"));
         assertTrue(info.isInRange("2001:db8::"));
         assertTrue(info.isInRange("2001:db8:ffff:ffff:ffff:ffff:ffff:ffff"));
         assertTrue(info.isInRange("2001:db8:1234:5678:9abc:def0:1234:5678"));

         // Addresses out of range
         assertFalse(info.isInRange("2001:db9::1"));
         assertFalse(info.isInRange("2001:db7::1"));
         assertFalse(info.isInRange("2002:db8::1"));
         assertFalse(info.isInRange("::1"));
     }

     @Test
     void testIsInRangeWithInvalidString() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
         final SubnetInfo info = utils.getInfo();

         assertThrows(IllegalArgumentException.class, () -> info.isInRange("not-an-address"));
         assertThrows(IllegalArgumentException.class, () -> info.isInRange("192.168.1.1"));
     }

     @Test
     void testIsInRangeWithBigInteger() throws UnknownHostException {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
         final SubnetInfo info = utils.getInfo();

         // Test with null
         assertFalse(info.isInRange((BigInteger) null));

         final BigInteger inRange = new BigInteger(1, InetAddress.getByName("2001:db8::1").getAddress());
         assertTrue(info.isInRange(inRange));
         final BigInteger outOfRange = new BigInteger(1, InetAddress.getByName("2001:db9::1").getAddress());
         assertFalse(info.isInRange(outOfRange));
     }

     @Test
     void testIsInRangeWithByteArray() throws UnknownHostException {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
         final SubnetInfo info = utils.getInfo();

         // Test with null
         assertFalse(info.isInRange((byte[]) null));

         // Test with wrong length
         assertFalse(info.isInRange(new byte[4]));
         assertFalse(info.isInRange(new byte[15]));
         assertFalse(info.isInRange(new byte[17]));

         assertTrue(info.isInRange(InetAddress.getByName("2001:db8::1").getAddress()));
         assertFalse(info.isInRange(InetAddress.getByName("2001:db9::1").getAddress()));
     }

     @Test
     void testIsInRangeWithInet6Address() throws UnknownHostException {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
         final SubnetInfo info = utils.getInfo();

         // Test with actual Inet6Address
         final Inet6Address addr = (Inet6Address) InetAddress.getByName("2001:db8::1");
         assertTrue(info.isInRange(addr));

         final Inet6Address addrOutside = (Inet6Address) InetAddress.getByName("2001:db9::1");
         assertFalse(info.isInRange(addrOutside));

         // Test with null
         assertFalse(info.isInRange((Inet6Address) null));
     }

     @Test
     void testLinkLocalAddress() {
         final SubnetUtils6 utils = new SubnetUtils6("fe80::/10");
         final SubnetInfo info = utils.getInfo();

         assertTrue(info.isInRange("fe80::1"));
         assertTrue(info.isInRange("fe80::1:2:3:4"));
         assertFalse(info.isInRange("::1")); // Loopback is not link-local
     }

     @Test
     void testLoopbackAddress() {
         final SubnetUtils6 utils = new SubnetUtils6("::1/128");
         final SubnetInfo info = utils.getInfo();

         assertEquals(128, info.getPrefixLength());
         assertTrue(info.isInRange("::1"));
         assertFalse(info.isInRange("::2"));
     }

     @Test
     void testToString() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1/64");
         final SubnetInfo info = utils.getInfo();
         final String str = utils.toString();

         assertNotNull(str);
         assertTrue(str.contains("CIDR Signature"));
         assertTrue(str.contains("Network"));
         assertTrue(str.contains("First address"));
         assertTrue(str.contains("Last address"));
         assertTrue(str.contains("Address Count"));

         // note: The CIDR signature from toString can be fed back into the constructor
         final String cidr = info.getCidrSignature();
         final SubnetUtils6 roundTrip = new SubnetUtils6(cidr);
         final SubnetInfo roundTripInfo = roundTrip.getInfo();
         assertEquals(info.getPrefixLength(), roundTripInfo.getPrefixLength());
         assertEquals(info.getNetworkAddress(), roundTripInfo.getNetworkAddress());
         assertEquals(info.getHighAddress(), roundTripInfo.getHighAddress());
         assertEquals(info.getAddressCount(), roundTripInfo.getAddressCount());
         assertEquals(info.getCidrSignature(), roundTripInfo.getCidrSignature());
     }

     @Test
     void testUniqueLocalAddress() {
         // ULA range is fc00::/7
         final SubnetUtils6 utils = new SubnetUtils6("fd00::/8");
         final SubnetInfo info = utils.getInfo();

         assertTrue(info.isInRange("fd00::1"));
         assertTrue(info.isInRange("fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff"));
         assertFalse(info.isInRange("fc00::1")); // fc00::/8 is different from fd00::/8
     }

     @Test
     void testHighBitAddress() {
         final SubnetUtils6 utils = new SubnetUtils6("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff/128");
         final SubnetInfo info = utils.getInfo();

         assertEquals("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", info.getAddress());
         assertEquals("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", info.getNetworkAddress());
         assertEquals("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", info.getHighAddress());
         assertEquals(BigInteger.ONE, info.getAddressCount());
     }

     @Test
     void testGetLowAddress() {
         final SubnetUtils6 utils = new SubnetUtils6("2001:db8::100/120");
         final SubnetInfo info = utils.getInfo();

         // getLowAddress returns the network address (same as getNetworkAddress)
         assertEquals(info.getNetworkAddress(), info.getLowAddress());
         assertEquals("2001:db8:0:0:0:0:0:100", info.getLowAddress());
     }

     // All examples below are from https://datatracker.ietf.org/doc/html/rfc5952 to verify properly
     /**
      * RFC 5952 Section 1: all representations of the same address must parse identically.
      */
     @Test
     void testRfc5952Section1EquivalentRepresentations() {
         assertEquivalentSubnets(
                 "2001:db8:0:0:1:0:0:1/128",
                 "2001:0db8:0:0:1:0:0:1/128",
                 "2001:db8::1:0:0:1/128",
                 "2001:db8::0:1:0:0:1/128",
                 "2001:0db8::1:0:0:1/128",
                 "2001:db8:0:0:1::1/128",
                 "2001:db8:0000:0:1::1/128",
                 "2001:DB8:0:0:1::1/128"
         );
     }

     /**
      * RFC 5952 Section 2.1: leading zeros in each 16-bit group must not affect parsing.
      */
     @Test
     void testRfc5952Section21LeadingZeros() {
         assertEquivalentSubnets(
                 "2001:db8:aaaa:bbbb:cccc:dddd:eeee:0001/128",
                 "2001:db8:aaaa:bbbb:cccc:dddd:eeee:001/128",
                 "2001:db8:aaaa:bbbb:cccc:dddd:eeee:01/128",
                 "2001:db8:aaaa:bbbb:cccc:dddd:eeee:1/128"
         );
     }

     /**
      * RFC 5952 Section 2.2:  various :: compression positions must resolve to the same address.
      */
     @Test
     void testRfc5952Section22ZeroCompression() {
         assertEquivalentSubnets(
                 "2001:db8:0:0:0:0:0:1/128",
                 "2001:db8:0:0:0::1/128",
                 "2001:db8:0:0::1/128",
                 "2001:db8:0::1/128",
                 "2001:db8::1/128"
         );
     }

     /**
      * RFC 5952 Section 2.3:  uppercase, lowercase, and mixed-case hex digits must parse identically.
      */
     @Test
     void testRfc5952Section23CaseInsensitivity() {
         assertEquivalentSubnets(
                 "2001:db8:aaaa:bbbb:cccc:dddd:eeee:aaaa/128",
                 "2001:db8:aaaa:bbbb:cccc:dddd:eeee:AAAA/128",
                 "2001:db8:aaaa:bbbb:cccc:dddd:eeee:AaAa/128",
                 "2001:DB8:AAAA:BBBB:CCCC:DDDD:EEEE:AAAA/128"
         );
     }

     /**
      * RFC 5952 Section 4.1:  canonical form suppresses leading zeros.
      * Verifies that {@code 2001:0db8::0001} and {@code 2001:db8::1} produce the same output.
      */
     @Test
     void testRfc5952Section41CanonicalLeadingZeros() {
         final SubnetInfo a = new SubnetUtils6("2001:0db8::0001/128").getInfo();
         final SubnetInfo b = new SubnetUtils6("2001:db8::1/128").getInfo();
         assertEquals(a.getAddress(), b.getAddress());
     }

     /**
      * RFC 5952 Section 4.2.1: :: must compress the longest possible run.
      * Both forms represent the same address.
      */
     @Test
     void testRfc5952Section421MaximumShortening() {
         final SubnetInfo a = new SubnetUtils6("2001:db8::0:1/128").getInfo();
         final SubnetInfo b = new SubnetUtils6("2001:db8::1/128").getInfo();
         assertEquals(a.getAddress(), b.getAddress());
     }

     /**
      * RFC 5952 Section 4.2.3:  when two zero runs of equal length exist, the first must be compressed.
      * Both input forms must parse to the same address.
      */
     @Test
     void testRfc5952Section423FirstLongestRunCompressed() {
         assertEquivalentSubnets(
                 "2001:db8:0:0:1:0:0:1/128",
                 "2001:db8::1:0:0:1/128",
                 "2001:db8:0:0:1::1/128"
         );
     }

     private static void assertEquivalentSubnets(final String... cidrs) {
         final SubnetInfo reference = new SubnetUtils6(cidrs[0]).getInfo();
         for (int i = 1; i < cidrs.length; i++) {
             final SubnetInfo other = new SubnetUtils6(cidrs[i]).getInfo();
             assertEquals(reference.getNetworkAddress(), other.getNetworkAddress(),
                 cidrs[0] + " vs " + cidrs[i] + " network");
             assertEquals(reference.getHighAddress(), other.getHighAddress(),
                 cidrs[0] + " vs " + cidrs[i] + " high");
             assertEquals(reference.getAddress(), other.getAddress(),
                 cidrs[0] + " vs " + cidrs[i] + " address");
         }
     }

     @Test
     void testRfc5952Section5SpecialAddresses() {
         final SubnetInfo loopback = new SubnetUtils6("::1/128").getInfo();
         assertEquals("0:0:0:0:0:0:0:1", loopback.getAddress());

         final SubnetInfo unspecified = new SubnetUtils6("::/128").getInfo();
         assertEquals("0:0:0:0:0:0:0:0", unspecified.getAddress());
     }
 }
	/*
	* 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
	*
	* https://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.commons.net.util;

	import static org.junit.jupiter.api.Assertions.assertEquals;
	import static org.junit.jupiter.api.Assertions.assertFalse;
	import static org.junit.jupiter.api.Assertions.assertNotNull;
	import static org.junit.jupiter.api.Assertions.assertThrows;
	import static org.junit.jupiter.api.Assertions.assertTrue;

	import java.math.BigInteger;
	import java.net.Inet6Address;
	import java.net.InetAddress;
	import java.net.UnknownHostException;

	import org.apache.commons.net.util.SubnetUtils6.SubnetInfo;
	import org.junit.jupiter.api.Test;

	/**
	* Tests {@link SubnetUtils6}.
	*/
	class SubnetUtils6Test {

	private static final BigInteger TWO = BigInteger.valueOf(2);

	@Test
	void testBasicCidr64() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1/64");
	final SubnetInfo info = utils.getInfo();

	assertEquals(64, info.getPrefixLength());
	assertEquals("2001:db8:0:0:0:0:0:1", info.getAddress());
	assertEquals("2001:db8:0:0:0:0:0:0", info.getNetworkAddress());
	assertEquals("2001:db8:0:0:ffff:ffff:ffff:ffff", info.getHighAddress());
	// 2^64 addresses
	assertEquals(TWO.pow(64), info.getAddressCount());
	}

	@Test
	void testBasicCidr128() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1/128");
	final SubnetInfo info = utils.getInfo();

	assertEquals(128, info.getPrefixLength());
	assertEquals("2001:db8:0:0:0:0:0:1", info.getNetworkAddress());
	assertEquals("2001:db8:0:0:0:0:0:1", info.getHighAddress());
	assertEquals(BigInteger.ONE, info.getAddressCount());
	}

	@Test
	void testCidr0() {
	final SubnetUtils6 utils = new SubnetUtils6("::/0");
	final SubnetInfo info = utils.getInfo();

	assertEquals(0, info.getPrefixLength());
	assertEquals("0:0:0:0:0:0:0:0", info.getNetworkAddress());
	// 2^128 addresses
	assertEquals(TWO.pow(128), info.getAddressCount());
	}

	@Test
	void testCidr48() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8:abcd::/48");
	final SubnetInfo info = utils.getInfo();

	assertEquals(48, info.getPrefixLength());
	assertEquals("2001:db8:abcd:0:0:0:0:0", info.getNetworkAddress());
	assertEquals("2001:db8:abcd:ffff:ffff:ffff:ffff:ffff", info.getHighAddress());
	}

	@Test
	void testCompressedAddress() {
	final SubnetUtils6 utils = new SubnetUtils6("fe80::1/10");
	final SubnetInfo info = utils.getInfo();

	assertEquals(10, info.getPrefixLength());
	assertTrue(info.isInRange("fe80::1"));
	assertTrue(info.isInRange("fe80::ffff"));
	assertTrue(info.isInRange("febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff"));
	assertFalse(info.isInRange("fec0::1")); // Outside /10 range
	}

	@Test
	void testConstructorWithSeparateArgs() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1", 64);
	final SubnetInfo info = utils.getInfo();

	assertEquals(64, info.getPrefixLength());
	assertEquals("2001:db8:0:0:0:0:0:0", info.getNetworkAddress());
	}

	@Test
	void testFullAddress() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:0db8:0000:0000:0000:0000:0000:0001/64");
	final SubnetInfo info = utils.getInfo();

	assertEquals(64, info.getPrefixLength());
	assertEquals("2001:db8:0:0:0:0:0:0", info.getNetworkAddress());
	}

	@Test
	void testGetCidrSignature() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1/64");
	final SubnetInfo info = utils.getInfo();

	assertEquals("2001:db8:0:0:0:0:0:1/64", info.getCidrSignature());
	}

	@Test
	void testInvalidCidr() {
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6(null));
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1"));
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1/"));
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1/129"));
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1/-1"));
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1/abc"));
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("not-an-address/64"));
	}

	@Test
	void testInvalidTwoArgConstructor() {
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1", 129));
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("2001:db8::1", -1));
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("not-an-address", 64));
	}

	@Test
	void testInvalidIPv4Address() {
	// IPv4 addresses should be rejected
	assertThrows(IllegalArgumentException.class, () -> new SubnetUtils6("192.168.1.1/24"));
	}

	@Test
	void testIsInRange() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
	final SubnetInfo info = utils.getInfo();

	// Addresses in range
	assertTrue(info.isInRange("2001:db8::1"));
	assertTrue(info.isInRange("2001:db8::"));
	assertTrue(info.isInRange("2001:db8:ffff:ffff:ffff:ffff:ffff:ffff"));
	assertTrue(info.isInRange("2001:db8:1234:5678:9abc:def0:1234:5678"));

	// Addresses out of range
	assertFalse(info.isInRange("2001:db9::1"));
	assertFalse(info.isInRange("2001:db7::1"));
	assertFalse(info.isInRange("2002:db8::1"));
	assertFalse(info.isInRange("::1"));
	}

	@Test
	void testIsInRangeWithInvalidString() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
	final SubnetInfo info = utils.getInfo();

	assertThrows(IllegalArgumentException.class, () -> info.isInRange("not-an-address"));
	assertThrows(IllegalArgumentException.class, () -> info.isInRange("192.168.1.1"));
	}

	@Test
	void testIsInRangeWithBigInteger() throws UnknownHostException {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
	final SubnetInfo info = utils.getInfo();

	// Test with null
	assertFalse(info.isInRange((BigInteger) null));

	final BigInteger inRange = new BigInteger(1, InetAddress.getByName("2001:db8::1").getAddress());
	assertTrue(info.isInRange(inRange));
	final BigInteger outOfRange = new BigInteger(1, InetAddress.getByName("2001:db9::1").getAddress());
	assertFalse(info.isInRange(outOfRange));
	}

	@Test
	void testIsInRangeWithByteArray() throws UnknownHostException {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
	final SubnetInfo info = utils.getInfo();

	// Test with null
	assertFalse(info.isInRange((byte[]) null));

	// Test with wrong length
	assertFalse(info.isInRange(new byte[4]));
	assertFalse(info.isInRange(new byte[15]));
	assertFalse(info.isInRange(new byte[17]));

	assertTrue(info.isInRange(InetAddress.getByName("2001:db8::1").getAddress()));
	assertFalse(info.isInRange(InetAddress.getByName("2001:db9::1").getAddress()));
	}

	@Test
	void testIsInRangeWithInet6Address() throws UnknownHostException {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::/32");
	final SubnetInfo info = utils.getInfo();

	// Test with actual Inet6Address
	final Inet6Address addr = (Inet6Address) InetAddress.getByName("2001:db8::1");
	assertTrue(info.isInRange(addr));

	final Inet6Address addrOutside = (Inet6Address) InetAddress.getByName("2001:db9::1");
	assertFalse(info.isInRange(addrOutside));

	// Test with null
	assertFalse(info.isInRange((Inet6Address) null));
	}

	@Test
	void testLinkLocalAddress() {
	final SubnetUtils6 utils = new SubnetUtils6("fe80::/10");
	final SubnetInfo info = utils.getInfo();

	assertTrue(info.isInRange("fe80::1"));
	assertTrue(info.isInRange("fe80::1:2:3:4"));
	assertFalse(info.isInRange("::1")); // Loopback is not link-local
	}

	@Test
	void testLoopbackAddress() {
	final SubnetUtils6 utils = new SubnetUtils6("::1/128");
	final SubnetInfo info = utils.getInfo();

	assertEquals(128, info.getPrefixLength());
	assertTrue(info.isInRange("::1"));
	assertFalse(info.isInRange("::2"));
	}

	@Test
	void testToString() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::1/64");
	final SubnetInfo info = utils.getInfo();
	final String str = utils.toString();

	assertNotNull(str);
	assertTrue(str.contains("CIDR Signature"));
	assertTrue(str.contains("Network"));
	assertTrue(str.contains("First address"));
	assertTrue(str.contains("Last address"));
	assertTrue(str.contains("Address Count"));

	// note: The CIDR signature from toString can be fed back into the constructor
	final String cidr = info.getCidrSignature();
	final SubnetUtils6 roundTrip = new SubnetUtils6(cidr);
	final SubnetInfo roundTripInfo = roundTrip.getInfo();
	assertEquals(info.getPrefixLength(), roundTripInfo.getPrefixLength());
	assertEquals(info.getNetworkAddress(), roundTripInfo.getNetworkAddress());
	assertEquals(info.getHighAddress(), roundTripInfo.getHighAddress());
	assertEquals(info.getAddressCount(), roundTripInfo.getAddressCount());
	assertEquals(info.getCidrSignature(), roundTripInfo.getCidrSignature());
	}

	@Test
	void testUniqueLocalAddress() {
	// ULA range is fc00::/7
	final SubnetUtils6 utils = new SubnetUtils6("fd00::/8");
	final SubnetInfo info = utils.getInfo();

	assertTrue(info.isInRange("fd00::1"));
	assertTrue(info.isInRange("fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff"));
	assertFalse(info.isInRange("fc00::1")); // fc00::/8 is different from fd00::/8
	}

	@Test
	void testHighBitAddress() {
	final SubnetUtils6 utils = new SubnetUtils6("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff/128");
	final SubnetInfo info = utils.getInfo();

	assertEquals("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", info.getAddress());
	assertEquals("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", info.getNetworkAddress());
	assertEquals("ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff", info.getHighAddress());
	assertEquals(BigInteger.ONE, info.getAddressCount());
	}

	@Test
	void testGetLowAddress() {
	final SubnetUtils6 utils = new SubnetUtils6("2001:db8::100/120");
	final SubnetInfo info = utils.getInfo();

	// getLowAddress returns the network address (same as getNetworkAddress)
	assertEquals(info.getNetworkAddress(), info.getLowAddress());
	assertEquals("2001:db8:0:0:0:0:0:100", info.getLowAddress());
	}

	// All examples below are from https://datatracker.ietf.org/doc/html/rfc5952 to verify properly
	/**
	* RFC 5952 Section 1: all representations of the same address must parse identically.
	*/
	@Test
	void testRfc5952Section1EquivalentRepresentations() {
	assertEquivalentSubnets(
	"2001:db8:0:0:1:0:0:1/128",
	"2001:0db8:0:0:1:0:0:1/128",
	"2001:db8::1:0:0:1/128",
	"2001:db8::0:1:0:0:1/128",
	"2001:0db8::1:0:0:1/128",
	"2001:db8:0:0:1::1/128",
	"2001:db8:0000:0:1::1/128",
	"2001:DB8:0:0:1::1/128"
	);
	}

	/**
	* RFC 5952 Section 2.1: leading zeros in each 16-bit group must not affect parsing.
	*/
	@Test
	void testRfc5952Section21LeadingZeros() {
	assertEquivalentSubnets(
	"2001:db8:aaaa:bbbb:cccc:dddd:eeee:0001/128",
	"2001:db8:aaaa:bbbb:cccc:dddd:eeee:001/128",
	"2001:db8:aaaa:bbbb:cccc:dddd:eeee:01/128",
	"2001:db8:aaaa:bbbb:cccc:dddd:eeee:1/128"
	);
	}

	/**
	* RFC 5952 Section 2.2: various :: compression positions must resolve to the same address.
	*/
	@Test
	void testRfc5952Section22ZeroCompression() {
	assertEquivalentSubnets(
	"2001:db8:0:0:0:0:0:1/128",
	"2001:db8:0:0:0::1/128",
	"2001:db8:0:0::1/128",
	"2001:db8:0::1/128",
	"2001:db8::1/128"
	);
	}

	/**
	* RFC 5952 Section 2.3: uppercase, lowercase, and mixed-case hex digits must parse identically.
	*/
	@Test
	void testRfc5952Section23CaseInsensitivity() {
	assertEquivalentSubnets(
	"2001:db8:aaaa:bbbb:cccc:dddd:eeee:aaaa/128",
	"2001:db8:aaaa:bbbb:cccc:dddd:eeee:AAAA/128",
	"2001:db8:aaaa:bbbb:cccc:dddd:eeee:AaAa/128",
	"2001:DB8:AAAA:BBBB:CCCC:DDDD:EEEE:AAAA/128"
	);
	}

	/**
	* RFC 5952 Section 4.1: canonical form suppresses leading zeros.
	* Verifies that {@code 2001:0db8::0001} and {@code 2001:db8::1} produce the same output.
	*/
	@Test
	void testRfc5952Section41CanonicalLeadingZeros() {
	final SubnetInfo a = new SubnetUtils6("2001:0db8::0001/128").getInfo();
	final SubnetInfo b = new SubnetUtils6("2001:db8::1/128").getInfo();
	assertEquals(a.getAddress(), b.getAddress());
	}

	/**
	* RFC 5952 Section 4.2.1: :: must compress the longest possible run.
	* Both forms represent the same address.
	*/
	@Test
	void testRfc5952Section421MaximumShortening() {
	final SubnetInfo a = new SubnetUtils6("2001:db8::0:1/128").getInfo();
	final SubnetInfo b = new SubnetUtils6("2001:db8::1/128").getInfo();
	assertEquals(a.getAddress(), b.getAddress());
	}

	/**
	* RFC 5952 Section 4.2.3: when two zero runs of equal length exist, the first must be compressed.
	* Both input forms must parse to the same address.
	*/
	@Test
	void testRfc5952Section423FirstLongestRunCompressed() {
	assertEquivalentSubnets(
	"2001:db8:0:0:1:0:0:1/128",
	"2001:db8::1:0:0:1/128",
	"2001:db8:0:0:1::1/128"
	);
	}

	private static void assertEquivalentSubnets(final String... cidrs) {
	final SubnetInfo reference = new SubnetUtils6(cidrs[0]).getInfo();
	for (int i = 1; i < cidrs.length; i++) {
	final SubnetInfo other = new SubnetUtils6(cidrs[i]).getInfo();
	assertEquals(reference.getNetworkAddress(), other.getNetworkAddress(),
	cidrs[0] + " vs " + cidrs[i] + " network");
	assertEquals(reference.getHighAddress(), other.getHighAddress(),
	cidrs[0] + " vs " + cidrs[i] + " high");
	assertEquals(reference.getAddress(), other.getAddress(),
	cidrs[0] + " vs " + cidrs[i] + " address");
	}
	}

	@Test
	void testRfc5952Section5SpecialAddresses() {
	final SubnetInfo loopback = new SubnetUtils6("::1/128").getInfo();
	assertEquals("0:0:0:0:0:0:0:1", loopback.getAddress());

	final SubnetInfo unspecified = new SubnetUtils6("::/128").getInfo();
	assertEquals("0:0:0:0:0:0:0:0", unspecified.getAddress());
	}
	}