Add TunnelInterface API and KernelResourceRecords

This change adds one KernelResourceRecord type (TunnelInterfaceRecord),
and adds methods for the creation of TunnelInterfaces, as well as the
application of Transforms to the given TunnelInterfaces

As part of the generation of ikeys/okeys, a ReserveKeyTracker manages a
java bitset to avoid collisions and reserve/release keys.

Bug: 63588681
Test: Compiles, CTS, unit tests all pass on AOSP_marlin
Change-Id: I9e9b6455e27073acd4491eae666aa966b3b10e0f

1 files changed, 21 insertions, 0 deletions

diff --git a/tests/net/java/com/android/server/IpSecServiceTest.java b/tests/net/java/com/android/server/IpSecServiceTest.java
index a375b600ca60..2c94a601fbf6 100644
--- a/tests/net/java/com/android/server/IpSecServiceTest.java
+++ b/tests/net/java/com/android/server/IpSecServiceTest.java
@@ -635,4 +635,25 @@ public class IpSecServiceTest {
         verify(mMockNetd).ipSecSetEncapSocketOwner(argThat(fdMatcher), eq(Os.getuid()));
         mIpSecService.closeUdpEncapsulationSocket(udpEncapResp.resourceId);
     }
+
+    @Test
+    public void testReserveNetId() {
+        int start = mIpSecService.TUN_INTF_NETID_START;
+        for (int i = 0; i < mIpSecService.TUN_INTF_NETID_RANGE; i++) {
+            assertEquals(start + i, mIpSecService.reserveNetId());
+        }
+
+        // Check that resource exhaustion triggers an exception
+        try {
+            mIpSecService.reserveNetId();
+            fail("Did not throw error for all netIds reserved");
+        } catch (IllegalStateException expected) {
+        }
+
+        // Now release one and try again
+        int releasedNetId =
+                mIpSecService.TUN_INTF_NETID_START + mIpSecService.TUN_INTF_NETID_RANGE / 2;
+        mIpSecService.releaseNetId(releasedNetId);
+        assertEquals(releasedNetId, mIpSecService.reserveNetId());
+    }
 }