Merge "[CTT-5] Stop update TCP conntrack entry timeout" am: 69ccea4839

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1760691

Change-Id: Ib1e1c1f2ccdf85bd3a7fd2275abb7ee144207b58
This commit is contained in:
Nucca Chen
2021-07-13 12:17:43 +00:00
committed by Automerger Merge Worker
2 changed files with 90 additions and 43 deletions

View File

@@ -123,9 +123,14 @@ public class BpfCoordinator {
return makeMapPath((downstream ? "downstream" : "upstream") + ipVersion);
}
// TODO: probably to remember what the timeout updated things to last is. But that requires
// either r/w map entries (which seems bad/racy) or a separate map to keep track of all flows
// and remember when they were updated and with what timeout.
@VisibleForTesting
static final int CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS = 60_000;
@VisibleForTesting
static final int CONNTRACK_TIMEOUT_UPDATE_SLACK_MS = 20_000;
@VisibleForTesting
static final int NF_CONNTRACK_TCP_TIMEOUT_ESTABLISHED = 432_000;
@VisibleForTesting
static final int NF_CONNTRACK_UDP_TIMEOUT_STREAM = 180;
@@ -1904,6 +1909,23 @@ public class BpfCoordinator {
}
}
boolean requireConntrackTimeoutUpdate(long nowNs, long lastUsedNs, int proto) {
// Refreshing tcp timeout without checking tcp state may make the conntrack entry live
// 5 days (432000s) even while the session is being closed. Its BPF rule may not be
// deleted for 5 days because the tcp state gets stuck and conntrack delete message is
// not sent. Note that both the conntrack monitor and refreshing timeout updater are
// in the same thread. Beware while the tcp status may be changed running in refreshing
// timeout updater and may read out-of-date tcp stats.
// See nf_conntrack_tcp_timeout_established in kernel document.
// TODO: support refreshing TCP conntrack timeout.
if (proto == OsConstants.IPPROTO_TCP) return false;
// The timeout requirement check needs the slack time because the scheduled timer may
// be not precise. The timeout update has a chance to be missed.
return (nowNs - lastUsedNs) < (long) (CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS
+ CONNTRACK_TIMEOUT_UPDATE_SLACK_MS) * 1_000_000;
}
private void refreshAllConntrackTimeouts() {
final long now = mDeps.elapsedRealtimeNanos();
@@ -1911,7 +1933,7 @@ public class BpfCoordinator {
// 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) {
if (requireConntrackTimeoutUpdate(now, v.lastUsed, k.l4proto)) {
updateConntrackTimeout((byte) k.l4proto,
parseIPv4Address(k.src4), (short) k.srcPort,
parseIPv4Address(k.dst4), (short) k.dstPort);
@@ -1919,10 +1941,10 @@ public class BpfCoordinator {
});
// Reverse the source and destination {address, port} from downstream value because
// #updateConntrackTimeout refresh the timeout of netlink attribute CTA_TUPLE_ORIG
// #updateConntrackTimeout refreshes 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) {
if (requireConntrackTimeoutUpdate(now, v.lastUsed, k.l4proto)) {
updateConntrackTimeout((byte) k.l4proto,
parseIPv4Address(v.dst46), (short) v.dstPort,
parseIPv4Address(v.src46), (short) v.srcPort);

View File

@@ -41,7 +41,7 @@ import static android.system.OsConstants.NETLINK_NETFILTER;
import static com.android.dx.mockito.inline.extended.ExtendedMockito.doReturn;
import static com.android.dx.mockito.inline.extended.ExtendedMockito.staticMockMarker;
import static com.android.networkstack.tethering.BpfCoordinator.CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS;
import static com.android.networkstack.tethering.BpfCoordinator.NF_CONNTRACK_TCP_TIMEOUT_ESTABLISHED;
import static com.android.networkstack.tethering.BpfCoordinator.CONNTRACK_TIMEOUT_UPDATE_SLACK_MS;
import static com.android.networkstack.tethering.BpfCoordinator.NF_CONNTRACK_UDP_TIMEOUT_STREAM;
import static com.android.networkstack.tethering.BpfCoordinator.StatsType;
import static com.android.networkstack.tethering.BpfCoordinator.StatsType.STATS_PER_IFACE;
@@ -1526,23 +1526,27 @@ public class BpfCoordinatorTest {
}
private void checkRefreshConntrackTimeout(final TestBpfMap<Tether4Key, Tether4Value> bpfMap,
final Tether4Key tcpKey, final Tether4Value tcpValue, final Tether4Key udpKey,
final Tether4Value udpValue) throws Exception {
int proto, final Tether4Key key, final Tether4Value value) throws Exception {
if (proto != IPPROTO_TCP && proto != IPPROTO_UDP) {
fail("Not support protocol " + proto);
}
// Both system elapsed time since boot and the rule last used time are used to measure
// the rule expiration. In this test, all test rules are fixed the last used time to 0.
// Set the different testing elapsed time to make the rule to be valid or expired.
//
// Timeline:
// 0 60 (seconds)
// +---+---+---+---+--...--+---+---+---+---+---+- ..
// | CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS |
// +---+---+---+---+--...--+---+---+---+---+---+- ..
// |<- valid diff ->|
// |<- expired diff ->|
// ^ ^ ^
// last used time elapsed time (valid) elapsed time (expired)
final long validTime = (CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS - 1) * 1_000_000L;
final long expiredTime = (CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS + 1) * 1_000_000L;
// CONNTRACK_TIMEOUT_UPDATE_SLACK_MS
// ->| |<-
// +---+---+---+---+---+--...--+---+---+---+---+---+-..-+---+-- ..
// | CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS |
// +---+---+---+---+---+--...--+---+---+---+---+---+-..-+---+-- ..
// |<- valid diff ->|
// |<- expired diff ->|
// ^ ^ ^
// last used time elapsed time (valid) elapsed time (expired)
final long validTimeNs = CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS * 1_000_000L;
final long expiredTimeNs = (CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS
+ CONNTRACK_TIMEOUT_UPDATE_SLACK_MS + 1) * 1_000_000L;
// Static mocking for NetlinkSocket.
MockitoSession mockSession = ExtendedMockito.mockitoSession()
@@ -1551,30 +1555,27 @@ public class BpfCoordinatorTest {
try {
final BpfCoordinator coordinator = makeBpfCoordinator();
coordinator.startPolling();
bpfMap.insertEntry(tcpKey, tcpValue);
bpfMap.insertEntry(udpKey, udpValue);
bpfMap.insertEntry(key, value);
// [1] Don't refresh contrack timeout.
setElapsedRealtimeNanos(expiredTime);
setElapsedRealtimeNanos(expiredTimeNs);
mTestLooper.moveTimeForward(CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS);
waitForIdle();
ExtendedMockito.verifyNoMoreInteractions(staticMockMarker(NetlinkSocket.class));
ExtendedMockito.clearInvocations(staticMockMarker(NetlinkSocket.class));
// [2] Refresh contrack timeout.
setElapsedRealtimeNanos(validTime);
// [2] Refresh contrack timeout. UDP Only.
setElapsedRealtimeNanos(validTimeNs);
mTestLooper.moveTimeForward(CONNTRACK_TIMEOUT_UPDATE_INTERVAL_MS);
waitForIdle();
final byte[] expectedNetlinkTcp = ConntrackMessage.newIPv4TimeoutUpdateRequest(
IPPROTO_TCP, PRIVATE_ADDR, (int) PRIVATE_PORT, REMOTE_ADDR,
(int) REMOTE_PORT, NF_CONNTRACK_TCP_TIMEOUT_ESTABLISHED);
final byte[] expectedNetlinkUdp = ConntrackMessage.newIPv4TimeoutUpdateRequest(
IPPROTO_UDP, PRIVATE_ADDR, (int) PRIVATE_PORT, REMOTE_ADDR,
(int) REMOTE_PORT, NF_CONNTRACK_UDP_TIMEOUT_STREAM);
ExtendedMockito.verify(() -> NetlinkSocket.sendOneShotKernelMessage(
eq(NETLINK_NETFILTER), eq(expectedNetlinkTcp)));
ExtendedMockito.verify(() -> NetlinkSocket.sendOneShotKernelMessage(
eq(NETLINK_NETFILTER), eq(expectedNetlinkUdp)));
if (proto == IPPROTO_UDP) {
final byte[] expectedNetlinkUdp = ConntrackMessage.newIPv4TimeoutUpdateRequest(
IPPROTO_UDP, PRIVATE_ADDR, (int) PRIVATE_PORT, REMOTE_ADDR,
(int) REMOTE_PORT, NF_CONNTRACK_UDP_TIMEOUT_STREAM);
ExtendedMockito.verify(() -> NetlinkSocket.sendOneShotKernelMessage(
eq(NETLINK_NETFILTER), eq(expectedNetlinkUdp)));
}
ExtendedMockito.verifyNoMoreInteractions(staticMockMarker(NetlinkSocket.class));
ExtendedMockito.clearInvocations(staticMockMarker(NetlinkSocket.class));
@@ -1591,33 +1592,57 @@ public class BpfCoordinatorTest {
@Test
@IgnoreUpTo(Build.VERSION_CODES.R)
public void testRefreshConntrackTimeout_Upstream4Map() throws Exception {
public void testRefreshConntrackTimeout_Upstream4MapTcp() throws Exception {
// TODO: Replace the dependencies BPF map with a non-mocked TestBpfMap object.
final TestBpfMap<Tether4Key, Tether4Value> bpfUpstream4Map =
new TestBpfMap<>(Tether4Key.class, Tether4Value.class);
doReturn(bpfUpstream4Map).when(mDeps).getBpfUpstream4Map();
final Tether4Key tcpKey = makeUpstream4Key(IPPROTO_TCP);
final Tether4Key udpKey = makeUpstream4Key(IPPROTO_UDP);
final Tether4Value tcpValue = makeUpstream4Value();
final Tether4Value udpValue = makeUpstream4Value();
final Tether4Key key = makeUpstream4Key(IPPROTO_TCP);
final Tether4Value value = makeUpstream4Value();
checkRefreshConntrackTimeout(bpfUpstream4Map, tcpKey, tcpValue, udpKey, udpValue);
checkRefreshConntrackTimeout(bpfUpstream4Map, IPPROTO_TCP, key, value);
}
@Test
@IgnoreUpTo(Build.VERSION_CODES.R)
public void testRefreshConntrackTimeout_Downstream4Map() throws Exception {
public void testRefreshConntrackTimeout_Upstream4MapUdp() throws Exception {
// TODO: Replace the dependencies BPF map with a non-mocked TestBpfMap object.
final TestBpfMap<Tether4Key, Tether4Value> bpfUpstream4Map =
new TestBpfMap<>(Tether4Key.class, Tether4Value.class);
doReturn(bpfUpstream4Map).when(mDeps).getBpfUpstream4Map();
final Tether4Key key = makeUpstream4Key(IPPROTO_UDP);
final Tether4Value value = makeUpstream4Value();
checkRefreshConntrackTimeout(bpfUpstream4Map, IPPROTO_UDP, key, value);
}
@Test
@IgnoreUpTo(Build.VERSION_CODES.R)
public void testRefreshConntrackTimeout_Downstream4MapTcp() throws Exception {
// TODO: Replace the dependencies BPF map with a non-mocked TestBpfMap object.
final TestBpfMap<Tether4Key, Tether4Value> bpfDownstream4Map =
new TestBpfMap<>(Tether4Key.class, Tether4Value.class);
doReturn(bpfDownstream4Map).when(mDeps).getBpfDownstream4Map();
final Tether4Key tcpKey = makeDownstream4Key(IPPROTO_TCP);
final Tether4Key udpKey = makeDownstream4Key(IPPROTO_UDP);
final Tether4Value tcpValue = makeDownstream4Value();
final Tether4Value udpValue = makeDownstream4Value();
final Tether4Key key = makeDownstream4Key(IPPROTO_TCP);
final Tether4Value value = makeDownstream4Value();
checkRefreshConntrackTimeout(bpfDownstream4Map, tcpKey, tcpValue, udpKey, udpValue);
checkRefreshConntrackTimeout(bpfDownstream4Map, IPPROTO_TCP, key, value);
}
@Test
@IgnoreUpTo(Build.VERSION_CODES.R)
public void testRefreshConntrackTimeout_Downstream4MapUdp() throws Exception {
// TODO: Replace the dependencies BPF map with a non-mocked TestBpfMap object.
final TestBpfMap<Tether4Key, Tether4Value> bpfDownstream4Map =
new TestBpfMap<>(Tether4Key.class, Tether4Value.class);
doReturn(bpfDownstream4Map).when(mDeps).getBpfDownstream4Map();
final Tether4Key key = makeDownstream4Key(IPPROTO_UDP);
final Tether4Value value = makeDownstream4Value();
checkRefreshConntrackTimeout(bpfDownstream4Map, IPPROTO_UDP, key, value);
}
}