Merge "Add a new IpPrefix class and use it in RouteInfo." into lmp-preview-dev

core/java/android/net/IpPrefix.java

@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed 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 android.net;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+import java.util.Arrays;
+
+/**
+ * This class represents an IP prefix, i.e., a contiguous block of IP addresses aligned on a
+ * power of two boundary (also known as an "IP subnet"). A prefix is specified by two pieces of
+ * information:
+ *
+ * <ul>
+ * <li>A starting IP address (IPv4 or IPv6). This is the first IP address of the prefix.
+ * <li>A prefix length. This specifies the length of the prefix by specifing the number of bits
+ *     in the IP address, starting from the most significant bit in network byte order, that
+ *     are constant for all addresses in the prefix.
+ * </ul>
+ *
+ * For example, the prefix <code>192.0.2.0/24</code> covers the 256 IPv4 addresses from
+ * <code>192.0.2.0</code> to <code>192.0.2.255</code>, inclusive, and the prefix
+ * <code>2001:db8:1:2</code>  covers the 2^64 IPv6 addresses from <code>2001:db8:1:2::</code> to
+ * <code>2001:db8:1:2:ffff:ffff:ffff:ffff</code>, inclusive.
+ *
+ * Objects of this class are immutable.
+ */
+public final class IpPrefix implements Parcelable {
+    private final byte[] address;  // network byte order
+    private final int prefixLength;
+
+    /**
+     * Constructs a new {@code IpPrefix} from a byte array containing an IPv4 or IPv6 address in
+     * network byte order and a prefix length.
+     *
+     * @param address the IP address. Must be non-null and exactly 4 or 16 bytes long.
+     * @param prefixLength the prefix length. Must be &gt;= 0 and &lt;= (32 or 128) (IPv4 or IPv6).
+     *
+     * @hide
+     */
+    public IpPrefix(byte[] address, int prefixLength) {
+        if (address.length != 4 && address.length != 16) {
+            throw new IllegalArgumentException(
+                    "IpPrefix has " + address.length + " bytes which is neither 4 nor 16");
+        }
+        if (prefixLength < 0 || prefixLength > (address.length * 8)) {
+            throw new IllegalArgumentException("IpPrefix with " + address.length +
+                    " bytes has invalid prefix length " + prefixLength);
+        }
+        this.address = address.clone();
+        this.prefixLength = prefixLength;
+        // TODO: Validate that the non-prefix bits are zero
+    }
+
+    /**
+     * @hide
+     */
+    public IpPrefix(InetAddress address, int prefixLength) {
+        this(address.getAddress(), prefixLength);
+    }
+
+    /**
+     * Compares this {@code IpPrefix} object against the specified object in {@code obj}. Two
+     * objects are equal if they have the same startAddress and prefixLength.
+     *
+     * @param obj the object to be tested for equality.
+     * @return {@code true} if both objects are equal, {@code false} otherwise.
+     */
+    @Override
+    public boolean equals(Object obj) {
+        if (!(obj instanceof IpPrefix)) {
+            return false;
+        }
+        IpPrefix that = (IpPrefix) obj;
+        return Arrays.equals(this.address, that.address) && this.prefixLength == that.prefixLength;
+    }
+
+    /**
+     * Gets the hashcode of the represented IP prefix.
+     *
+     * @return the appropriate hashcode value.
+     */
+    @Override
+    public int hashCode() {
+        return Arrays.hashCode(address) + 11 * prefixLength;
+    }
+
+    /**
+     * Returns a copy of the first IP address in the prefix. Modifying the returned object does not
+     * change this object's contents.
+     *
+     * @return the address in the form of a byte array.
+     */
+    public InetAddress getAddress() {
+        try {
+            return InetAddress.getByAddress(address);
+        } catch (UnknownHostException e) {
+            // Cannot happen. InetAddress.getByAddress can only throw an exception if the byte
+            // array is the wrong length, but we check that in the constructor.
+            return null;
+        }
+    }
+
+    /**
+     * Returns a copy of the IP address bytes in network order (the highest order byte is the zeroth
+     * element). Modifying the returned array does not change this object's contents.
+     *
+     * @return the address in the form of a byte array.
+     */
+    public byte[] getRawAddress() {
+        return address.clone();
+    }
+
+    /**
+     * Returns the prefix length of this {@code IpAddress}.
+     *
+     * @return the prefix length.
+     */
+    public int getPrefixLength() {
+        return prefixLength;
+    }
+
+    /**
+     * Implement the Parcelable interface.
+     */
+    public int describeContents() {
+        return 0;
+    }
+
+    /**
+     * Implement the Parcelable interface.
+     */
+    public void writeToParcel(Parcel dest, int flags) {
+        dest.writeByteArray(address);
+        dest.writeInt(prefixLength);
+    }
+
+    /**
+     * Implement the Parcelable interface.
+     */
+    public static final Creator<IpPrefix> CREATOR =
+            new Creator<IpPrefix>() {
+                public IpPrefix createFromParcel(Parcel in) {
+                    byte[] address = in.createByteArray();
+                    int prefixLength = in.readInt();
+                    return new IpPrefix(address, prefixLength);
+                }
+
+                public IpPrefix[] newArray(int size) {
+                    return new IpPrefix[size];
+                }
+            };
+}

core/java/android/net/LinkProperties.java

@@ -44,7 +44,7 @@ import java.util.List;
  * does not affect live networks.
  *
  */
-public class LinkProperties implements Parcelable {
+public final class LinkProperties implements Parcelable {
     // The interface described by the network link.
     private String mIfaceName;
     private ArrayList<LinkAddress> mLinkAddresses = new ArrayList<LinkAddress>();
@@ -77,9 +77,15 @@ public class LinkProperties implements Parcelable {
         }
     }
 
+    /**
+     * @hide
+     */
     public LinkProperties() {
     }
 
+    /**
+     * @hide
+     */
     public LinkProperties(LinkProperties source) {
         if (source != null) {
             mIfaceName = source.getInterfaceName();
@@ -267,7 +273,7 @@ public class LinkProperties implements Parcelable {
     }
 
     /**
-     * Returns all the {@link LinkAddress} for DNS servers on this link.
+     * Returns all the {@link InetAddress} for DNS servers on this link.
      *
      * @return An umodifiable {@link List} of {@link InetAddress} for DNS servers on
      *         this link.
@@ -457,7 +463,6 @@ public class LinkProperties implements Parcelable {
 
     /**
      * Implement the Parcelable interface
-     * @hide
      */
     public int describeContents() {
         return 0;

core/java/android/net/RouteInfo.java

@@ -35,10 +35,10 @@ import java.util.Objects;
  *
  * A route contains three pieces of information:
  * <ul>
- * <li>a destination {@link LinkAddress} for directly-connected subnets.  If this is
+ * <li>a destination {@link IpPrefix} specifying the network destinations covered by this route.
- *     {@code null} it indicates a default route of the address family (IPv4 or IPv6)
+ *     If this is {@code null} it indicates a default route of the address family (IPv4 or IPv6)
  *     implied by the gateway IP address.
- * <li>a gateway {@link InetAddress} for default routes.  If this is {@code null} it
+ * <li>a gateway {@link InetAddress} indicating the next hop to use.  If this is {@code null} it
  *     indicates a directly-connected route.
  * <li>an interface (which may be unspecified).
  * </ul>
@@ -46,9 +46,10 @@ import java.util.Objects;
  * destination and gateway are both specified, they must be of the same address family
  * (IPv4 or IPv6).
  */
-public class RouteInfo implements Parcelable {
+public final class RouteInfo implements Parcelable {
     /**
      * The IP destination address for this route.
+     * TODO: Make this an IpPrefix.
      */
     private final LinkAddress mDestination;
 
@@ -80,6 +81,19 @@ public class RouteInfo implements Parcelable {
      * @param destination the destination prefix
      * @param gateway the IP address to route packets through
      * @param iface the interface name to send packets on
+     *
+     * TODO: Convert to use IpPrefix.
+     *
+     * @hide
+     */
+    public RouteInfo(IpPrefix destination, InetAddress gateway, String iface) {
+        this(destination == null ? null :
+                new LinkAddress(destination.getAddress(), destination.getPrefixLength()),
+                gateway, iface);
+    }
+
+    /**
+     * @hide
      */
     public RouteInfo(LinkAddress destination, InetAddress gateway, String iface) {
         if (destination == null) {
@@ -128,8 +142,17 @@ public class RouteInfo implements Parcelable {
      * <p>
      * Destination and gateway may not both be null.
      *
-     * @param destination the destination address and prefix in a {@link LinkAddress}
+     * @param destination the destination address and prefix in an {@link IpPrefix}
      * @param gateway the {@link InetAddress} to route packets through
+     *
+     * @hide
+     */
+    public RouteInfo(IpPrefix destination, InetAddress gateway) {
+        this(destination, gateway, null);
+    }
+
+    /**
+     * @hide
      */
     public RouteInfo(LinkAddress destination, InetAddress gateway) {
         this(destination, gateway, null);
@@ -139,16 +162,27 @@ public class RouteInfo implements Parcelable {
      * Constructs a default {@code RouteInfo} object.
      *
      * @param gateway the {@link InetAddress} to route packets through
+     *
+     * @hide
      */
     public RouteInfo(InetAddress gateway) {
-        this(null, gateway, null);
+        this((LinkAddress) null, gateway, null);
     }
 
     /**
      * Constructs a {@code RouteInfo} object representing a direct connected subnet.
      *
-     * @param destination the {@link LinkAddress} describing the address and prefix
+     * @param destination the {@link IpPrefix} describing the address and prefix
      *                    length of the subnet.
+     *
+     * @hide
+     */
+    public RouteInfo(IpPrefix destination) {
+        this(destination, null, null);
+    }
+
+    /**
+     * @hide
      */
     public RouteInfo(LinkAddress destination) {
         this(destination, null, null);
@@ -194,11 +228,19 @@ public class RouteInfo implements Parcelable {
     }
 
     /**
-     * Retrieves the destination address and prefix length in the form of a {@link LinkAddress}.
+     * Retrieves the destination address and prefix length in the form of an {@link IpPrefix}.
      *
-     * @return {@link LinkAddress} specifying the destination.  This is never {@code null}.
+     * @return {@link IpPrefix} specifying the destination.  This is never {@code null}.
      */
-    public LinkAddress getDestination() {
+    public IpPrefix getDestination() {
+        return new IpPrefix(mDestination.getAddress(), mDestination.getPrefixLength());
+    }
+
+    /**
+     * TODO: Convert callers to use IpPrefix and then remove.
+     * @hide
+     */
+    public LinkAddress getDestinationLinkAddress() {
         return mDestination;
     }
 
@@ -233,7 +275,8 @@ public class RouteInfo implements Parcelable {
     /**
      * Indicates if this route is a host route (ie, matches only a single host address).
      *
-     * @return {@code true} if the destination has a prefix length of 32/128 for v4/v6.
+     * @return {@code true} if the destination has a prefix length of 32 or 128 for IPv4 or IPv6,
+     * respectively.
      * @hide
      */
     public boolean isHostRoute() {
@@ -295,13 +338,22 @@ public class RouteInfo implements Parcelable {
         return bestRoute;
     }
 
+    /**
+     * Returns a human-readable description of this object.
+     */
     public String toString() {
         String val = "";
         if (mDestination != null) val = mDestination.toString();
-        if (mGateway != null) val += " -> " + mGateway.getHostAddress();
+        val += " ->";
+        if (mGateway != null) val += " " + mGateway.getHostAddress();
+        if (mInterface != null) val += " " + mInterface;
         return val;
     }
 
+    /**
+     * Compares this RouteInfo object against the specified object and indicates if they are equal.
+     * @return {@code true} if the objects are equal, {@code false} otherwise.
+     */
     public boolean equals(Object obj) {
         if (this == obj) return true;
 
@@ -314,6 +366,9 @@ public class RouteInfo implements Parcelable {
                 Objects.equals(mInterface, target.getInterface());
     }
 
+    /**
+     *  Returns a hashcode for this <code>RouteInfo</code> object.
+     */
     public int hashCode() {
         return (mDestination == null ? 0 : mDestination.hashCode() * 41)
                 + (mGateway == null ? 0 :mGateway.hashCode() * 47)
@@ -323,7 +378,6 @@ public class RouteInfo implements Parcelable {
 
     /**
      * Implement the Parcelable interface
-     * @hide
      */
     public int describeContents() {
         return 0;
@@ -331,7 +385,6 @@ public class RouteInfo implements Parcelable {
 
     /**
      * Implement the Parcelable interface
-     * @hide
      */
     public void writeToParcel(Parcel dest, int flags) {
         if (mDestination == null) {
@@ -354,7 +407,6 @@ public class RouteInfo implements Parcelable {
 
     /**
      * Implement the Parcelable interface.
-     * @hide
      */
     public static final Creator<RouteInfo> CREATOR =
         new Creator<RouteInfo>() {

core/tests/coretests/src/android/net/RouteInfoTest.java

@@ -43,17 +43,17 @@ public class RouteInfoTest extends TestCase {
 
         // Invalid input.
         try {
-            r = new RouteInfo(null, null, "rmnet0");
+            r = new RouteInfo((LinkAddress) null, null, "rmnet0");
             fail("Expected RuntimeException:  destination and gateway null");
         } catch(RuntimeException e) {}
 
         // Null destination is default route.
-        r = new RouteInfo(null, Address("2001:db8::1"), null);
+        r = new RouteInfo((LinkAddress) null, Address("2001:db8::1"), null);
         assertEquals(Prefix("::/0"), r.getDestination());
         assertEquals(Address("2001:db8::1"), r.getGateway());
         assertNull(r.getInterface());
 
-        r = new RouteInfo(null, Address("192.0.2.1"), "wlan0");
+        r = new RouteInfo((LinkAddress) null, Address("192.0.2.1"), "wlan0");
         assertEquals(Prefix("0.0.0.0/0"), r.getDestination());
         assertEquals(Address("192.0.2.1"), r.getGateway());
         assertEquals("wlan0", r.getInterface());

services/core/java/com/android/server/ConnectivityService.java

@@ -1871,7 +1871,7 @@ public class ConnectivityService extends IConnectivityManager.Stub {
                             mNetd.addRoute(netId, r);
                         }
                         if (exempt) {
-                            LinkAddress dest = r.getDestination();
+                            LinkAddress dest = r.getDestinationLinkAddress();
                             if (!mExemptAddresses.contains(dest)) {
                                 mNetd.setHostExemption(dest);
                                 mExemptAddresses.add(dest);
@@ -1904,7 +1904,7 @@ public class ConnectivityService extends IConnectivityManager.Stub {
                             } else {
                                 mNetd.removeRoute(netId, r);
                             }
-                            LinkAddress dest = r.getDestination();
+                            LinkAddress dest = r.getDestinationLinkAddress();
                             if (mExemptAddresses.contains(dest)) {
                                 mNetd.clearHostExemption(dest);
                                 mExemptAddresses.remove(dest);