[CTT-2] Clean up unused {function, exception} and improve readability
- Remove ipv4MappedAddressBytesToIpv4Address because it can be covered
by parseIPv4Address.
- Remove IllegalArgumentException from parseIPv4Address because it has
never happened
- Reverse the order of upstream and downstream timeout refreshing in
refreshAllConntrackTimeouts for readability because both source and
destination of the downstream are opposite direction to the
upstream.
Bug: 190783768
Bug: 192804833
Test: atest TetheringCoverageTests
Change-Id: I6a1e44777a4357dd3847c2e2bb1fc6c3cf01617c
diff --git a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
index 14d26e8..8c15880 100644
--- a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
+++ b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
@@ -1443,25 +1443,6 @@
return addr6;
}
- @Nullable
- private Inet4Address ipv4MappedAddressBytesToIpv4Address(final byte[] addr46) {
- if (addr46.length != 16) return null;
- if (addr46[0] != 0 || addr46[1] != 0 || addr46[2] != 0 || addr46[3] != 0
- || addr46[4] != 0 || addr46[5] != 0 || addr46[6] != 0 || addr46[7] != 0
- || addr46[8] != 0 && addr46[9] != 0 || (addr46[10] & 0xff) != 0xff
- || (addr46[11] & 0xff) != 0xff) {
- return null;
- }
-
- final byte[] addr4 = new byte[4];
- addr4[0] = addr46[12];
- addr4[1] = addr46[13];
- addr4[2] = addr46[14];
- addr4[3] = addr46[15];
-
- return parseIPv4Address(addr4);
- }
-
// TODO: parse CTA_PROTOINFO of conntrack event in ConntrackMonitor. For TCP, only add rules
// while TCP status is established.
@VisibleForTesting
@@ -1861,7 +1842,7 @@
try {
final InetAddress ia = Inet4Address.getByAddress(addrBytes);
if (ia instanceof Inet4Address) return (Inet4Address) ia;
- } catch (UnknownHostException | IllegalArgumentException e) {
+ } catch (UnknownHostException e) {
mLog.e("Failed to parse IPv4 address: " + e);
}
return null;
@@ -1899,24 +1880,25 @@
private void refreshAllConntrackTimeouts() {
final long now = mDeps.elapsedRealtimeNanos();
+ // TODO: Consider ignoring TCP traffic on upstream and monitor on downstream only
+ // because TCP is a bidirectional traffic. Probably don't need to extend timeout by
+ // both directions for TCP.
+ mBpfCoordinatorShim.tetherOffloadRuleForEach(UPSTREAM, (k, v) -> {
+ if ((now - v.lastUsed) / 1_000_000 < CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS) {
+ updateConntrackTimeout((byte) k.l4proto,
+ parseIPv4Address(k.src4), (short) k.srcPort,
+ parseIPv4Address(k.dst4), (short) k.dstPort);
+ }
+ });
+
// Reverse the source and destination {address, port} from downstream value because
// #updateConntrackTimeout refresh the timeout of netlink attribute CTA_TUPLE_ORIG
// which is opposite direction for downstream map value.
mBpfCoordinatorShim.tetherOffloadRuleForEach(DOWNSTREAM, (k, v) -> {
if ((now - v.lastUsed) / 1_000_000 < CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS) {
updateConntrackTimeout((byte) k.l4proto,
- ipv4MappedAddressBytesToIpv4Address(v.dst46), (short) v.dstPort,
- ipv4MappedAddressBytesToIpv4Address(v.src46), (short) v.srcPort);
- }
- });
-
- // TODO: Consider ignoring TCP traffic on upstream and monitor on downstream only
- // because TCP is a bidirectional traffic. Probably don't need to extend timeout by
- // both directions for TCP.
- mBpfCoordinatorShim.tetherOffloadRuleForEach(UPSTREAM, (k, v) -> {
- if ((now - v.lastUsed) / 1_000_000 < CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS) {
- updateConntrackTimeout((byte) k.l4proto, parseIPv4Address(k.src4),
- (short) k.srcPort, parseIPv4Address(k.dst4), (short) k.dstPort);
+ parseIPv4Address(v.dst46), (short) v.dstPort,
+ parseIPv4Address(v.src46), (short) v.srcPort);
}
});
}