Activate outgoing keys when incoming tag is recognised.

bramble-core/src/main/java/org/briarproject/bramble/transport/TransportKeyManagerImpl.java

@@ -355,6 +355,16 @@ class TransportKeyManagerImpl implements TransportKeyManager {
 			db.setReorderingWindow(txn, tagCtx.keySetId, transportId,
 					inKeys.getRotationPeriod(), window.getBase(),
 					window.getBitmap());
+			// If the outgoing keys are inactive, activate them
+			MutableKeySet ks = keys.get(tagCtx.keySetId);
+			MutableOutgoingKeys outKeys =
+					ks.getTransportKeys().getCurrentOutgoingKeys();
+			if (!outKeys.isActive()) {
+				LOG.info("Activating outgoing keys");
+				outKeys.activate();
+				considerReplacingOutgoingKeys(ks);
+				db.setTransportKeysActive(txn, transportId, tagCtx.keySetId);
+			}
 			return ctx;
 		} finally {
 			lock.unlock();

bramble-core/src/test/java/org/briarproject/bramble/transport/TransportKeyManagerImplTest.java

@@ -286,9 +286,10 @@ public class TransportKeyManagerImplTest extends BrambleMockTestCase {
 	public void testTagIsNotRecognisedTwice() throws Exception {
 		boolean alice = random.nextBoolean();
 		TransportKeys transportKeys = createTransportKeys(1000, 0, true);
+		Transaction txn = new Transaction(null, false);
+
 		// Keep a copy of the tags
 		List<byte[]> tags = new ArrayList<>();
-		Transaction txn = new Transaction(null, false);
 
 		context.checking(new Expectations() {{
 			oneOf(transportCrypto).deriveTransportKeys(transportId, masterKey,
@@ -418,19 +419,9 @@ public class TransportKeyManagerImplTest extends BrambleMockTestCase {
 		TransportKeys transportKeys = createTransportKeys(1000, 0, false);
 		Transaction txn = new Transaction(null, false);
 
+		expectAddUnboundKeysNoRotation(alice, transportKeys, txn);
+
 		context.checking(new Expectations() {{
-			oneOf(transportCrypto).deriveTransportKeys(transportId, masterKey,
-					1000, alice, false);
-			will(returnValue(transportKeys));
-			// Get the current time (the start of rotation period 1000)
-			oneOf(clock).currentTimeMillis();
-			will(returnValue(rotationPeriodLength * 1000));
-			// Rotate the transport keys (the keys are unaffected)
-			oneOf(transportCrypto).rotateTransportKeys(transportKeys, 1000);
-			will(returnValue(transportKeys));
-			// Save the unbound keys
-			oneOf(db).addTransportKeys(txn, null, transportKeys);
-			will(returnValue(keySetId));
 			// When the keys are bound, encode the tags (3 sets)
 			for (long i = 0; i < REORDERING_WINDOW_SIZE; i++) {
 				exactly(3).of(transportCrypto).encodeTag(
@@ -470,7 +461,74 @@ public class TransportKeyManagerImplTest extends BrambleMockTestCase {
 		assertEquals(transportId, ctx.getTransportId());
 		assertEquals(tagKey, ctx.getTagKey());
 		assertEquals(headerKey, ctx.getHeaderKey());
-		assertEquals(0, ctx.getStreamNumber());
+		assertEquals(0L, ctx.getStreamNumber());
+	}
+
+	@Test
+	public void testRecognisingTagActivatesOutgoingKeys() throws Exception {
+		boolean alice = random.nextBoolean();
+		TransportKeys transportKeys = createTransportKeys(1000, 0, false);
+		Transaction txn = new Transaction(null, false);
+
+		// Keep a copy of the tags
+		List<byte[]> tags = new ArrayList<>();
+
+		expectAddUnboundKeysNoRotation(alice, transportKeys, txn);
+
+		context.checking(new Expectations() {{
+			// When the keys are bound, encode the tags (3 sets)
+			for (long i = 0; i < REORDERING_WINDOW_SIZE; i++) {
+				exactly(3).of(transportCrypto).encodeTag(
+						with(any(byte[].class)), with(tagKey),
+						with(PROTOCOL_VERSION), with(i));
+				will(new EncodeTagAction(tags));
+			}
+			// Save the key binding
+			oneOf(db).bindTransportKeys(txn, contactId, transportId, keySetId);
+			// Encode a new tag after sliding the window
+			oneOf(transportCrypto).encodeTag(with(any(byte[].class)),
+					with(tagKey), with(PROTOCOL_VERSION),
+					with((long) REORDERING_WINDOW_SIZE));
+			will(new EncodeTagAction(tags));
+			// Save the reordering window (previous rotation period, base 1)
+			oneOf(db).setReorderingWindow(txn, keySetId, transportId, 999,
+					1, new byte[REORDERING_WINDOW_SIZE / 8]);
+			// Activate the keys
+			oneOf(db).setTransportKeysActive(txn, transportId, keySetId);
+			// Increment the stream counter
+			oneOf(db).incrementStreamCounter(txn, transportId, keySetId);
+		}});
+
+		TransportKeyManager transportKeyManager = new TransportKeyManagerImpl(
+				db, transportCrypto, dbExecutor, scheduler, clock, transportId,
+				maxLatency);
+		// The timestamp is at the start of rotation period 1000
+		long timestamp = rotationPeriodLength * 1000;
+		assertEquals(keySetId, transportKeyManager.addUnboundKeys(txn,
+				masterKey, timestamp, alice));
+		transportKeyManager.bindKeys(txn, contactId, keySetId);
+		// The keys are inactive so no stream context should be returned
+		assertFalse(transportKeyManager.canSendOutgoingStreams(contactId));
+		assertNull(transportKeyManager.getStreamContext(txn, contactId));
+		// Recognising an incoming tag should activate the outgoing keys
+		assertEquals(REORDERING_WINDOW_SIZE * 3, tags.size());
+		byte[] tag = tags.get(0);
+		StreamContext ctx = transportKeyManager.getStreamContext(txn, tag);
+		assertNotNull(ctx);
+		assertEquals(contactId, ctx.getContactId());
+		assertEquals(transportId, ctx.getTransportId());
+		assertEquals(tagKey, ctx.getTagKey());
+		assertEquals(headerKey, ctx.getHeaderKey());
+		assertEquals(0L, ctx.getStreamNumber());
+		// The keys are active so a stream context should be returned
+		assertTrue(transportKeyManager.canSendOutgoingStreams(contactId));
+		ctx = transportKeyManager.getStreamContext(txn, contactId);
+		assertNotNull(ctx);
+		assertEquals(contactId, ctx.getContactId());
+		assertEquals(transportId, ctx.getTransportId());
+		assertEquals(tagKey, ctx.getTagKey());
+		assertEquals(headerKey, ctx.getHeaderKey());
+		assertEquals(0L, ctx.getStreamNumber());
 	}
 
 	@Test
@@ -479,19 +537,9 @@ public class TransportKeyManagerImplTest extends BrambleMockTestCase {
 		TransportKeys transportKeys = createTransportKeys(1000, 0, false);
 		Transaction txn = new Transaction(null, false);
 
+		expectAddUnboundKeysNoRotation(alice, transportKeys, txn);
+
 		context.checking(new Expectations() {{
-			oneOf(transportCrypto).deriveTransportKeys(transportId, masterKey,
-					1000, alice, false);
-			will(returnValue(transportKeys));
-			// Get the current time (the start of rotation period 1000)
-			oneOf(clock).currentTimeMillis();
-			will(returnValue(rotationPeriodLength * 1000));
-			// Rotate the transport keys (the keys are unaffected)
-			oneOf(transportCrypto).rotateTransportKeys(transportKeys, 1000);
-			will(returnValue(transportKeys));
-			// Save the unbound keys
-			oneOf(db).addTransportKeys(txn, null, transportKeys);
-			will(returnValue(keySetId));
 			// Remove the unbound keys
 			oneOf(db).removeTransportKeys(txn, transportId, keySetId);
 		}});
@@ -533,6 +581,24 @@ public class TransportKeyManagerImplTest extends BrambleMockTestCase {
 		}});
 	}
 
+	private void expectAddUnboundKeysNoRotation(boolean alice,
+			TransportKeys transportKeys, Transaction txn) throws Exception {
+		context.checking(new Expectations() {{
+			oneOf(transportCrypto).deriveTransportKeys(transportId, masterKey,
+					1000, alice, false);
+			will(returnValue(transportKeys));
+			// Get the current time (the start of rotation period 1000)
+			oneOf(clock).currentTimeMillis();
+			will(returnValue(rotationPeriodLength * 1000));
+			// Rotate the transport keys (the keys are unaffected)
+			oneOf(transportCrypto).rotateTransportKeys(transportKeys, 1000);
+			will(returnValue(transportKeys));
+			// Save the unbound keys
+			oneOf(db).addTransportKeys(txn, null, transportKeys);
+			will(returnValue(keySetId));
+		}});
+	}
+
 	private TransportKeys createTransportKeys(long rotationPeriod,
 			long streamCounter, boolean active) {
 		IncomingKeys inPrev = new IncomingKeys(tagKey, headerKey,