Pass DNS server info notifications to observers.

These are sent if the device receives IPv6 Router Advertisements
with DNS server configuration options. Currently, nothing listens
to them; in a future change we will use them as IPv6 DNS servers.

[Cherry-pick of 416740ad4d9132005a71dc0883334e852235a18a]

Bug: 9180552
Change-Id: I05000c0cd3867a68ab390102e8470b6912a9d3aa

4 files changed, 90 insertions, 0 deletions

diff --git a/core/java/android/net/INetworkManagementEventObserver.aidl b/core/java/android/net/INetworkManagementEventObserver.aidl
index b76e4c24599c..c720c7b1da79 100644
--- a/core/java/android/net/INetworkManagementEventObserver.aidl
+++ b/core/java/android/net/INetworkManagementEventObserver.aidl
@@ -90,4 +90,13 @@ interface INetworkManagementEventObserver {
      * @param active  True if the interface is actively transmitting data, false if it is idle.
      */
     void interfaceClassDataActivityChanged(String label, boolean active);
+
+    /**
+     * Information about available DNS servers has been received.
+     *
+     * @param iface The interface on which the information was received.
+     * @param lifetime The time in seconds for which the DNS servers may be used.
+     * @param servers The IP addresses of the DNS servers.
+     */
+    void interfaceDnsServerInfo(String iface, long lifetime, in String[] servers);
 }
diff --git a/core/java/com/android/server/net/BaseNetworkObserver.java b/core/java/com/android/server/net/BaseNetworkObserver.java
index fa54c5f3eeaf..a02c60273b09 100644
--- a/core/java/com/android/server/net/BaseNetworkObserver.java
+++ b/core/java/com/android/server/net/BaseNetworkObserver.java
@@ -64,4 +64,9 @@ public class BaseNetworkObserver extends INetworkManagementEventObserver.Stub {
     public void limitReached(String limitName, String iface) {
         // default no-op
     }
+
+    @Override
+    public void interfaceDnsServerInfo(String iface, long lifetime, String[] servers) {
+        // default no-op
+    }
 }
diff --git a/services/java/com/android/server/NetworkManagementService.java b/services/java/com/android/server/NetworkManagementService.java
index 9a0d6485b315..8089fbc2339f 100644
--- a/services/java/com/android/server/NetworkManagementService.java
+++ b/services/java/com/android/server/NetworkManagementService.java
@@ -136,6 +136,7 @@ public class NetworkManagementService extends INetworkManagementService.Stub
         public static final int BandwidthControl          = 601;
         public static final int InterfaceClassActivity    = 613;
         public static final int InterfaceAddressChange    = 614;
+        public static final int InterfaceDnsServerInfo    = 615;
     }
 
     /**
@@ -431,6 +432,21 @@ public class NetworkManagementService extends INetworkManagementService.Stub
         mObservers.finishBroadcast();
     }
 
+    /**
+     * Notify our observers of DNS server information received.
+     */
+    private void notifyInterfaceDnsServerInfo(String iface, long lifetime, String[] addresses) {
+        final int length = mObservers.beginBroadcast();
+        for (int i = 0; i < length; i++) {
+            try {
+                mObservers.getBroadcastItem(i).interfaceDnsServerInfo(iface, lifetime, addresses);
+            } catch (RemoteException e) {
+            } catch (RuntimeException e) {
+            }
+        }
+        mObservers.finishBroadcast();
+    }
+
     //
     // Netd Callback handling
     //
@@ -535,6 +551,26 @@ public class NetworkManagementService extends INetworkManagementService.Stub
                     }
                     return true;
                     // break;
+            case NetdResponseCode.InterfaceDnsServerInfo:
+                    /*
+                     * Information about available DNS servers has been received.
+                     * Format: "NNN DnsInfo servers <interface> <lifetime> <servers>"
+                     */
+                    long lifetime;  // Actually a 32-bit unsigned integer.
+
+                    if (cooked.length == 6 &&
+                        cooked[1].equals("DnsInfo") &&
+                        cooked[2].equals("servers")) {
+                        try {
+                            lifetime = Long.parseLong(cooked[4]);
+                        } catch (NumberFormatException e) {
+                            throw new IllegalStateException(errorMessage);
+                        }
+                        String[] servers = cooked[5].split(",");
+                        notifyInterfaceDnsServerInfo(cooked[3], lifetime, servers);
+                    }
+                    return true;
+                    // break;
             default: break;
             }
             return false;
diff --git a/services/tests/servicestests/src/com/android/server/NetworkManagementServiceTest.java b/services/tests/servicestests/src/com/android/server/NetworkManagementServiceTest.java
index 30d4eff3dbec..4385dcd51bd1 100644
--- a/services/tests/servicestests/src/com/android/server/NetworkManagementServiceTest.java
+++ b/services/tests/servicestests/src/com/android/server/NetworkManagementServiceTest.java
@@ -172,6 +172,46 @@ public class NetworkManagementServiceTest extends AndroidTestCase {
         sendMessage("666 Address added 2001:db8::1/64 wlan0 1 0");
         // Invalid code.
 
+
+        /**
+         * DNS information broadcasts.
+         */
+        sendMessage("615 DnsInfo servers rmnet_usb0 3600 2001:db8::1");
+        expectSoon(observer).interfaceDnsServerInfo("rmnet_usb0", 3600,
+                new String[]{"2001:db8::1"});
+
+        sendMessage("615 DnsInfo servers wlan0 14400 2001:db8::1,2001:db8::2");
+        expectSoon(observer).interfaceDnsServerInfo("wlan0", 14400,
+                new String[]{"2001:db8::1", "2001:db8::2"});
+
+        // We don't check for negative lifetimes, only for parse errors.
+        sendMessage("615 DnsInfo servers wlan0 -3600 ::1");
+        expectSoon(observer).interfaceDnsServerInfo("wlan0", -3600,
+                new String[]{"::1"});
+
+        sendMessage("615 DnsInfo servers wlan0 SIXHUNDRED ::1");
+        // Non-numeric lifetime.
+
+        sendMessage("615 DnsInfo servers wlan0 2001:db8::1");
+        // Missing lifetime.
+
+        sendMessage("615 DnsInfo servers wlan0 3600");
+        // No servers.
+
+        sendMessage("615 DnsInfo servers 3600 wlan0 2001:db8::1,2001:db8::2");
+        // Non-numeric lifetime.
+
+        sendMessage("615 DnsInfo wlan0 7200 2001:db8::1,2001:db8::2");
+        // Invalid tokens.
+
+        sendMessage("666 DnsInfo servers wlan0 5400 2001:db8::1");
+        // Invalid code.
+
+        // No syntax checking on the addresses.
+        sendMessage("615 DnsInfo servers wlan0 600 ,::,,foo,::1,");
+        expectSoon(observer).interfaceDnsServerInfo("wlan0", 600,
+                new String[]{"", "::", "", "foo", "::1"});
+
         // Make sure nothing else was called.
         verifyNoMoreInteractions(observer);
     }