Added "allowConnectionsWithOlderPeerVersions" setting (default: true)

This controls whether to allow connections with peers below minPeerVersion.

If true, we won't sync with them but they can still sync with us, and will show in the peers list. This is the default, which allows older nodes to continue functioning, but prevents them from interfering with the sync behaviour of updated nodes.

If false, sync will be blocked both ways, and they will not appear in the peers list at all.

pom.xml

@@ -3,7 +3,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>org.qortal</groupId>
 	<artifactId>qortal</artifactId>
-	<version>1.5.0</version>
+	<version>1.5.1</version>
 	<packaging>jar</packaging>
 	<properties>
 		<skipTests>true</skipTests>

src/main/java/org/qortal/api/resource/CrossChainResource.java

@@ -262,6 +262,7 @@ public class CrossChainResource {
 
 		// We want both a minimum of 5 trades and enough trades to span at least 4 hours
 		int minimumCount = 5;
+		int maximumCount = 10;
 		long minimumPeriod = 4 * 60 * 60 * 1000L; // ms
 		Boolean isFinished = Boolean.TRUE;
 
@@ -276,7 +277,7 @@ public class CrossChainResource {
 				ACCT acct = acctInfo.getValue().get();
 
 				List<ATStateData> atStates = repository.getATRepository().getMatchingFinalATStatesQuorum(codeHash,
-						isFinished, acct.getModeByteOffset(), (long) AcctMode.REDEEMED.value, minimumCount, minimumPeriod);
+						isFinished, acct.getModeByteOffset(), (long) AcctMode.REDEEMED.value, minimumCount, maximumCount, minimumPeriod);
 
 				for (ATStateData atState : atStates) {
 					CrossChainTradeData crossChainTradeData = acct.populateTradeData(repository, atState);

src/main/java/org/qortal/block/Block.java

@@ -1998,6 +1998,10 @@ public class Block {
 
 	private void logDebugInfo() {
 		try {
+			// Avoid calculations if possible. We have to check against INFO here, since Level.isMoreSpecificThan() confusingly uses <= rather than just <
+			if (LOGGER.getLevel().isMoreSpecificThan(Level.INFO))
+				return;
+
 			if (this.repository == null || this.getMinter() == null || this.getBlockData() == null)
 				return;
 
@@ -2009,7 +2013,7 @@ public class Block {
 			LOGGER.debug(String.format("Online accounts: %d", this.getBlockData().getOnlineAccountsCount()));
 
 			BlockSummaryData blockSummaryData = new BlockSummaryData(this.getBlockData());
-			if (this.getParent() == null || this.getParent().getSignature() == null || blockSummaryData == null)
+			if (this.getParent() == null || this.getParent().getSignature() == null || blockSummaryData == null || minterLevel == 0)
 				return;
 
 			blockSummaryData.setMinterLevel(minterLevel);

src/main/java/org/qortal/controller/Controller.java

@@ -623,6 +623,11 @@ public class Controller extends Thread {
 		return peerChainTipData == null || peerChainTipData.getLastBlockSignature() == null || inferiorChainTips.contains(new ByteArray(peerChainTipData.getLastBlockSignature()));
 	};
 
+	public static final Predicate<Peer> hasOldVersion = peer -> {
+		final String minPeerVersion = Settings.getInstance().getMinPeerVersion();
+		return peer.isAtLeastVersion(minPeerVersion) == false;
+	};
+
 	private void potentiallySynchronize() throws InterruptedException {
 		// Already synchronizing via another thread?
 		if (this.isSynchronizing)
@@ -639,11 +644,15 @@ public class Controller extends Thread {
 		// Disregard peers that don't have a recent block
 		peers.removeIf(hasNoRecentBlock);
 
+		// Disregard peers that are on an old version
+		peers.removeIf(hasOldVersion);
+
 		checkRecoveryModeForPeers(peers);
 		if (recoveryMode) {
 			peers = Network.getInstance().getHandshakedPeers();
 			peers.removeIf(hasOnlyGenesisBlock);
 			peers.removeIf(hasMisbehaved);
+			peers.removeIf(hasOldVersion);
 		}
 
 		// Check we have enough peers to potentially synchronize

src/main/java/org/qortal/controller/Synchronizer.java

@@ -35,6 +35,7 @@ import org.qortal.network.message.Message.MessageType;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
+import org.qortal.settings.Settings;
 import org.qortal.transaction.Transaction;
 import org.qortal.utils.Base58;
 import org.qortal.utils.NTP;
@@ -57,9 +58,6 @@ public class Synchronizer {
 	/** Maximum number of block signatures we ask from peer in one go */
 	private static final int MAXIMUM_REQUEST_SIZE = 200; // XXX move to Settings?
 
-	/** Number of retry attempts if a peer fails to respond with the requested data */
-	private static final int MAXIMUM_RETRIES = 2; // XXX move to Settings?
-
 
 	private static Synchronizer instance;
 
@@ -748,6 +746,7 @@ public class Synchronizer {
 
 		LOGGER.debug(() -> String.format("Fetching peer %s chain from height %d, sig %.8s", peer, commonBlockHeight, commonBlockSig58));
 
+		final int maxRetries = Settings.getInstance().getMaxRetries();
 
 		// Overall plan: fetch peer's blocks first, then orphan, then apply
 
@@ -837,7 +836,7 @@ public class Synchronizer {
 				LOGGER.info(String.format("Peer %s failed to respond with block for height %d, sig %.8s", peer,
 						nextHeight, Base58.encode(nextPeerSignature)));
 
-				if (retryCount >= MAXIMUM_RETRIES) {
+				if (retryCount >= maxRetries) {
 
 					// If we have already received recent or newer blocks from this peer, go ahead and apply them
 					if (peerBlocks.size() > 0) {
@@ -875,9 +874,9 @@ public class Synchronizer {
 					peerBlockSignatures.clear();
 					numberSignaturesRequired = peerHeight - height;
 
-					// Retry until retryCount reaches MAXIMUM_RETRIES
+					// Retry until retryCount reaches maxRetries
 					retryCount++;
-					int triesRemaining = MAXIMUM_RETRIES - retryCount;
+					int triesRemaining = maxRetries - retryCount;
 					LOGGER.info(String.format("Re-issuing request to peer %s (%d attempt%s remaining)", peer, triesRemaining, (triesRemaining != 1 ? "s" : "")));
 					continue;
 				}

src/main/java/org/qortal/network/Handshake.java

@@ -4,7 +4,6 @@ import java.util.Arrays;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -51,7 +50,7 @@ public enum Handshake {
 
 			String versionString = helloMessage.getVersionString();
 
-			Matcher matcher = VERSION_PATTERN.matcher(versionString);
+			Matcher matcher = peer.VERSION_PATTERN.matcher(versionString);
 			if (!matcher.lookingAt()) {
 				LOGGER.debug(() -> String.format("Peer %s sent invalid HELLO version string '%s'", peer, versionString));
 				return null;
@@ -72,6 +71,15 @@ public enum Handshake {
 			peer.setPeersConnectionTimestamp(peersConnectionTimestamp);
 			peer.setPeersVersion(versionString, version);
 
+			if (Settings.getInstance().getAllowConnectionsWithOlderPeerVersions() == false) {
+				// Ensure the peer is running at least the minimum version allowed for connections
+				final String minPeerVersion = Settings.getInstance().getMinPeerVersion();
+				if (peer.isAtLeastVersion(minPeerVersion) == false) {
+					LOGGER.info(String.format("Ignoring peer %s because it is on an old version (%s)", peer, versionString));
+					return null;
+				}
+			}
+
 			return CHALLENGE;
 		}
 
@@ -244,8 +252,6 @@ public enum Handshake {
 	/** Maximum allowed difference between peer's reported timestamp and when they connected, in milliseconds. */
 	private static final long MAX_TIMESTAMP_DELTA = 30 * 1000L; // ms
 
-	private static final Pattern VERSION_PATTERN = Pattern.compile(Controller.VERSION_PREFIX + "(\\d{1,3})\\.(\\d{1,5})\\.(\\d{1,5})");
-
 	private static final long PEER_VERSION_131 = 0x0100030001L;
 
 	private static final int POW_BUFFER_SIZE_PRE_131 = 8 * 1024 * 1024; // bytes

src/main/java/org/qortal/network/Peer.java

@@ -20,9 +20,12 @@ import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.TimeUnit;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.qortal.controller.Controller;
 import org.qortal.data.block.CommonBlockData;
 import org.qortal.data.network.PeerChainTipData;
 import org.qortal.data.network.PeerData;
@@ -87,6 +90,9 @@ public class Peer {
 
 	byte[] ourChallenge;
 
+	// Versioning
+	public static final Pattern VERSION_PATTERN = Pattern.compile(Controller.VERSION_PREFIX + "(\\d{1,3})\\.(\\d{1,5})\\.(\\d{1,5})");
+
 	// Peer info
 
 	private final Object peerInfoLock = new Object();
@@ -634,6 +640,35 @@ public class Peer {
 	}
 
 
+	// Minimum version
+
+	public boolean isAtLeastVersion(String minVersionString) {
+		if (minVersionString == null)
+			return false;
+
+		// Add the version prefix
+		minVersionString = Controller.VERSION_PREFIX + minVersionString;
+
+		Matcher matcher = VERSION_PATTERN.matcher(minVersionString);
+		if (!matcher.lookingAt())
+			return false;
+
+		// We're expecting 3 positive shorts, so we can convert 1.2.3 into 0x0100020003
+		long minVersion = 0;
+		for (int g = 1; g <= 3; ++g) {
+			long value = Long.parseLong(matcher.group(g));
+
+			if (value < 0 || value > Short.MAX_VALUE)
+				return false;
+
+			minVersion <<= 16;
+			minVersion |= value;
+		}
+
+		return this.getPeersVersion() >= minVersion;
+	}
+
+
 	// Common block data
 
 	public boolean canUseCachedCommonBlockData() {

src/main/java/org/qortal/repository/ATRepository.java

@@ -98,7 +98,7 @@ public interface ATRepository {
 	 */
 	public List<ATStateData> getMatchingFinalATStatesQuorum(byte[] codeHash, Boolean isFinished,
 			Integer dataByteOffset, Long expectedValue,
-			int minimumCount, long minimumPeriod) throws DataException;
+			int minimumCount, int maximumCount, long minimumPeriod) throws DataException;
 
 	/**
 	 * Returns all ATStateData for a given block height.

src/main/java/org/qortal/repository/hsqldb/HSQLDBATRepository.java

@@ -454,7 +454,7 @@ public class HSQLDBATRepository implements ATRepository {
 	@Override
 	public List<ATStateData> getMatchingFinalATStatesQuorum(byte[] codeHash, Boolean isFinished,
 			Integer dataByteOffset, Long expectedValue,
-			int minimumCount, long minimumPeriod) throws DataException {
+			int minimumCount, int maximumCount, long minimumPeriod) throws DataException {
 		// We need most recent entry first so we can use its timestamp to slice further results
 		List<ATStateData> mostRecentStates = this.getMatchingFinalATStates(codeHash, isFinished,
 				dataByteOffset, expectedValue, null,
@@ -510,7 +510,8 @@ public class HSQLDBATRepository implements ATRepository {
 		bindParams.add(minimumHeight);
 		bindParams.add(minimumCount);
 
-		sql.append("ORDER BY FinalATStates.height DESC");
+		sql.append("ORDER BY FinalATStates.height DESC LIMIT ?");
+		bindParams.add(maximumCount);
 
 		List<ATStateData> atStates = new ArrayList<>();
 

src/main/java/org/qortal/settings/Settings.java

@@ -122,6 +122,15 @@ public class Settings {
 	private int maxNetworkThreadPoolSize = 20;
 	/** Maximum number of threads for network proof-of-work compute, used during handshaking. */
 	private int networkPoWComputePoolSize = 2;
+	/** Maximum number of retry attempts if a peer fails to respond with the requested data */
+	private int maxRetries = 2;
+
+	/** Minimum peer version number required in order to sync with them */
+	private String minPeerVersion = "1.5.0";
+	/** Whether to allow connections with peers below minPeerVersion
+	 * If true, we won't sync with them but they can still sync with us, and will show in the peers list
+	 * If false, sync will be blocked both ways, and they will not appear in the peers list */
+	private boolean allowConnectionsWithOlderPeerVersions = true;
 
 	// Which blockchains this node is running
 	private String blockchainConfig = null; // use default from resources
@@ -408,6 +417,12 @@ public class Settings {
 		return this.networkPoWComputePoolSize;
 	}
 
+	public int getMaxRetries() { return this.maxRetries; }
+
+	public String getMinPeerVersion() { return this.minPeerVersion; }
+
+	public boolean getAllowConnectionsWithOlderPeerVersions() { return this.allowConnectionsWithOlderPeerVersions; }
+
 	public String getBlockchainConfig() {
 		return this.blockchainConfig;
 	}

src/main/resources/blockchain.json

@@ -51,7 +51,7 @@
 		"atFindNextTransactionFix": 275000,
 		"newBlockSigHeight": 320000,
 		"shareBinFix": 399000,
-		"calcChainWeightTimestamp": 1616000000000
+		"calcChainWeightTimestamp": 1620579600000
 	},
 	"genesisInfo": {
 		"version": 4,