Merge "Add the NAT64 prefix to LinkProperties."

am: 983e77db4a

Change-Id: Ia1e6e1e584db12e57b245fa01651d289337906a3

core/java/android/net/LinkProperties.java

@@ -66,6 +66,7 @@ public final class LinkProperties implements Parcelable {
     private int mMtu;
     // in the format "rmem_min,rmem_def,rmem_max,wmem_min,wmem_def,wmem_max"
     private String mTcpBufferSizes;
+    private IpPrefix mNat64Prefix;
 
     private static final int MIN_MTU    = 68;
     private static final int MIN_MTU_V6 = 1280;
@@ -759,6 +760,32 @@ public final class LinkProperties implements Parcelable {
         return mHttpProxy;
     }
 
+    /**
+     * Returns the NAT64 prefix in use on this link, if any.
+     *
+     * @return the NAT64 prefix.
+     * @hide
+     */
+    public @Nullable IpPrefix getNat64Prefix() {
+        return mNat64Prefix;
+    }
+
+    /**
+     * Sets the NAT64 prefix in use on this link.
+     *
+     * Currently, only 96-bit prefixes (i.e., where the 32-bit IPv4 address is at the end of the
+     * 128-bit IPv6 address) are supported.
+     *
+     * @param prefix the NAT64 prefix.
+     * @hide
+     */
+    public void setNat64Prefix(IpPrefix prefix) {
+        if (prefix != null && prefix.getPrefixLength() != 96) {
+            throw new IllegalArgumentException("Only 96-bit prefixes are supported: " + prefix);
+        }
+        mNat64Prefix = prefix;  // IpPrefix objects are immutable.
+    }
+
     /**
      * Adds a stacked link.
      *
@@ -831,6 +858,7 @@ public final class LinkProperties implements Parcelable {
         mStackedLinks.clear();
         mMtu = 0;
         mTcpBufferSizes = null;
+        mNat64Prefix = null;
     }
 
     /**
@@ -908,6 +936,11 @@ public final class LinkProperties implements Parcelable {
             resultJoiner.add(mHttpProxy.toString());
         }
 
+        if (mNat64Prefix != null) {
+            resultJoiner.add("Nat64Prefix:");
+            resultJoiner.add(mNat64Prefix.toString());
+        }
+
         final Collection<LinkProperties> stackedLinksValues = mStackedLinks.values();
         if (!stackedLinksValues.isEmpty()) {
             final StringJoiner stackedLinksJoiner = new StringJoiner(",", "Stacked: [", "]");
@@ -1294,6 +1327,17 @@ public final class LinkProperties implements Parcelable {
         return Objects.equals(mTcpBufferSizes, target.mTcpBufferSizes);
     }
 
+    /**
+     * Compares this {@code LinkProperties} NAT64 prefix against the target.
+     *
+     * @param target LinkProperties to compare.
+     * @return {@code true} if both are identical, {@code false} otherwise.
+     * @hide
+     */
+    public boolean isIdenticalNat64Prefix(LinkProperties target) {
+        return Objects.equals(mNat64Prefix, target.mNat64Prefix);
+    }
+
     /**
      * Compares this {@code LinkProperties} instance against the target
      * LinkProperties in {@code obj}. Two LinkPropertieses are equal if
@@ -1330,7 +1374,8 @@ public final class LinkProperties implements Parcelable {
                 && isIdenticalHttpProxy(target)
                 && isIdenticalStackedLinks(target)
                 && isIdenticalMtu(target)
-                && isIdenticalTcpBufferSizes(target);
+                && isIdenticalTcpBufferSizes(target)
+                && isIdenticalNat64Prefix(target);
     }
 
     /**
@@ -1443,7 +1488,8 @@ public final class LinkProperties implements Parcelable {
                 + ((null == mTcpBufferSizes) ? 0 : mTcpBufferSizes.hashCode())
                 + (mUsePrivateDns ? 57 : 0)
                 + mPcscfs.size() * 67
-                + ((null == mPrivateDnsServerName) ? 0 : mPrivateDnsServerName.hashCode());
+                + ((null == mPrivateDnsServerName) ? 0 : mPrivateDnsServerName.hashCode())
+                + Objects.hash(mNat64Prefix);
     }
 
     /**
@@ -1484,6 +1530,8 @@ public final class LinkProperties implements Parcelable {
         } else {
             dest.writeByte((byte)0);
         }
+        dest.writeParcelable(mNat64Prefix, 0);
+
         ArrayList<LinkProperties> stackedLinks = new ArrayList<>(mStackedLinks.values());
         dest.writeList(stackedLinks);
     }
@@ -1535,6 +1583,7 @@ public final class LinkProperties implements Parcelable {
                 if (in.readByte() == 1) {
                     netProp.setHttpProxy(in.readParcelable(null));
                 }
+                netProp.setNat64Prefix(in.readParcelable(null));
                 ArrayList<LinkProperties> stackedLinks = new ArrayList<LinkProperties>();
                 in.readList(stackedLinks, LinkProperties.class.getClassLoader());
                 for (LinkProperties stackedLink: stackedLinks) {

tests/net/java/android/net/LinkPropertiesTest.java

@@ -18,6 +18,7 @@ package android.net;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
@@ -33,6 +34,9 @@ import android.support.test.runner.AndroidJUnit4;
 import android.system.OsConstants;
 import android.util.ArraySet;
 
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
 import java.net.InetAddress;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -41,9 +45,6 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Set;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
-
 @RunWith(AndroidJUnit4.class)
 @SmallTest
 public class LinkPropertiesTest {
@@ -503,6 +504,40 @@ public class LinkPropertiesTest {
         assertTrue(lp.equals(lp));
     }
 
+    @Test
+    public void testNat64Prefix() throws Exception {
+        LinkProperties lp = new LinkProperties();
+        lp.addLinkAddress(LINKADDRV4);
+        lp.addLinkAddress(LINKADDRV6);
+
+        assertNull(lp.getNat64Prefix());
+
+        IpPrefix p = new IpPrefix("64:ff9b::/96");
+        lp.setNat64Prefix(p);
+        assertEquals(p, lp.getNat64Prefix());
+
+        p = new IpPrefix("2001:db8:a:b:1:2:3::/96");
+        lp.setNat64Prefix(p);
+        assertEquals(p, lp.getNat64Prefix());
+
+        p = new IpPrefix("2001:db8:a:b:1:2::/80");
+        try {
+            lp.setNat64Prefix(p);
+        } catch (IllegalArgumentException expected) {
+        }
+
+        p = new IpPrefix("64:ff9b::/64");
+        try {
+            lp.setNat64Prefix(p);
+        } catch (IllegalArgumentException expected) {
+        }
+
+        assertEquals(new IpPrefix("2001:db8:a:b:1:2:3::/96"), lp.getNat64Prefix());
+
+        lp.setNat64Prefix(null);
+        assertNull(lp.getNat64Prefix());
+    }
+
     @Test
     public void testIsProvisioned() {
         LinkProperties lp4 = new LinkProperties();
@@ -815,7 +850,7 @@ public class LinkPropertiesTest {
     }
 
     @Test
-    public void testLinkPropertiesParcelable() {
+    public void testLinkPropertiesParcelable() throws Exception {
         LinkProperties source = new LinkProperties();
         source.setInterfaceName(NAME);
         // set 2 link addresses
@@ -833,6 +868,8 @@ public class LinkPropertiesTest {
 
         source.setMtu(MTU);
 
+        source.setNat64Prefix(new IpPrefix("2001:db8:1:2:64:64::/96"));
+
         Parcel p = Parcel.obtain();
         source.writeToParcel(p, /* flags */ 0);
         p.setDataPosition(0);