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SSU2: Detect and drop dup relay messages as Bob

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More SSU1 code removal (Intro. Mgr.)
This commit is contained in:
zzz
2024-11-04 12:29:44 -05:00
parent c9b17b8cd5
commit b2b86b2767
1 changed files with 35 additions and 6 deletions
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41
router/java/src/net/i2p/router/transport/udp/IntroductionManager.java
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@@ -28,6 +28,7 @@ import net.i2p.data.router.RouterInfo;
import net.i2p.router.RouterContext;
import net.i2p.router.transport.TransportUtil;
import net.i2p.util.Addresses;
import net.i2p.util.LHMCache;
import net.i2p.util.Log;
import net.i2p.util.SimpleTimer2;
import net.i2p.util.VersionComparator;
@@ -92,8 +93,8 @@ class IntroductionManager {
private final Map<Long, PeerState> _inbound;
/** map of relay nonce to alice PeerState who requested it */
private final ConcurrentHashMap<Long, PeerState2> _nonceToAlice;
private final Set<InetAddress> _recentHolePunches;
private long _lastHolePunchClean;
private final Map<Long, Object> _recentRelaysAsBob;
private static final Object DUMMY = new Object();
/**
* Limit since we ping to keep the conn open
@@ -122,8 +123,8 @@ class IntroductionManager {
_builder2 = transport.getBuilder2();
_outbound = new ConcurrentHashMap<Long, PeerState>(MAX_OUTBOUND);
_inbound = new ConcurrentHashMap<Long, PeerState>(MAX_INBOUND);
_nonceToAlice = (_builder2 != null) ? new ConcurrentHashMap<Long, PeerState2>(MAX_INBOUND) : null;
_recentHolePunches = new HashSet<InetAddress>(16);
_nonceToAlice = new ConcurrentHashMap<Long, PeerState2>(MAX_INBOUND);
_recentRelaysAsBob = new LHMCache<Long, Object>(8);
ctx.statManager().createRateStat("udp.receiveRelayIntro", "How often we get a relayed request for us to talk to someone?", "udp", UDPTransport.RATES);
ctx.statManager().createRateStat("udp.receiveRelayRequest", "How often we receive a good request to relay to someone else?", "udp", UDPTransport.RATES);
ctx.statManager().createRateStat("udp.receiveRelayRequestBadTag", "Received relay requests with bad/expired tag", "udp", UDPTransport.RATES);
@@ -506,6 +507,21 @@ class IntroductionManager {
// add a code for this?
rcode = SSU2Util.RELAY_REJECT_BOB_NO_TAG;
} else {
Long lnonce = Long.valueOf(nonce);
boolean isDup;
synchronized(_recentRelaysAsBob) {
isDup = _recentRelaysAsBob.put(lnonce, DUMMY) != null;
}
if (isDup) {
// fairly common from i2pd
if (_log.shouldInfo())
_log.info("Dropping dup relay request from " + alice
+ " for tag " + tag
+ " nonce " + nonce
+ " time " + time
+ " and relaying with " + charlie);
return;
}
aliceRI = _context.netDb().lookupRouterInfoLocally(alice.getRemotePeer());
if (aliceRI != null) {
// validate signed data
@@ -513,7 +529,7 @@ class IntroductionManager {
if (SSU2Util.validateSig(_context, SSU2Util.RELAY_REQUEST_PROLOGUE,
_context.routerHash(), charlie.getRemotePeer(), data, spk)) {
// save tag-to-alice mapping so we can forward the reply from charlie
PeerState2 old = _nonceToAlice.putIfAbsent(Long.valueOf(nonce), alice);
PeerState2 old = _nonceToAlice.putIfAbsent(lnonce, alice);
if (old != null && !old.equals(alice)) {
// dup tag
rcode = SSU2Util.RELAY_REJECT_BOB_UNSPEC;
@@ -541,6 +557,7 @@ class IntroductionManager {
_log.info("Receive relay request from " + alice
+ " for tag " + tag
+ " nonce " + nonce
+ " time " + time
+ " and relaying with " + charlie);
// put alice hash in intro data
@@ -865,7 +882,8 @@ class IntroductionManager {
return;
}
// Look up nonce to determine if we are Alice or Bob
PeerState2 alice = _nonceToAlice.remove(Long.valueOf(nonce));
Long lnonce = Long.valueOf(nonce);
PeerState2 alice = _nonceToAlice.remove(lnonce);
if (alice != null) {
// We are Bob, send to Alice
// Debug, check the signature, but send it along even if failed
@@ -901,6 +919,17 @@ class IntroductionManager {
alice.setLastSendTime(now);
} catch (IOException ioe) {}
} else {
boolean isDup;
synchronized(_recentRelaysAsBob) {
isDup = _recentRelaysAsBob.get(lnonce) != null;
}
if (isDup) {
// very rare
if (_log.shouldInfo())
_log.info("Dropping dup relay response as bob from charlie " + peer.getRemotePeer()
+ " for nonce " + nonce);
return;
}
// We are Alice, give to EstablishmentManager to check sig and process
if (_log.shouldInfo())
_log.info("Got relay response " + status + " as alice " + " nonce " + nonce + " from " + peer);