fix(PortProxy): Enhanced connection setup to handle pending data buffering before establishing outgoing connection

changelog.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## 2025-03-05 - 3.23.1 - fix(PortProxy)
+Enhanced connection setup to handle pending data buffering before establishing outgoing connection
+
+- Introduced pending data buffering to address issues with data reception before outgoing connection is fully established.
+- Removed immediate data piping in favor of buffering to ensure complete initial data transfer.
+- Added temporary data handler to collect incoming data during connection setup for precise activity tracking.
+
 ## 2025-03-03 - 3.23.0 - feat(documentation)
 Updated documentation with architecture flow diagrams.
 

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@push.rocks/smartproxy',
-  version: '3.23.0',
+  version: '3.23.1',
   description: 'A powerful proxy package that effectively handles high traffic, with features such as SSL/TLS support, port proxying, WebSocket handling, and dynamic routing with authentication options.'
 }

ts/classes.portproxy.ts

@@ -99,6 +99,7 @@ interface IConnectionRecord {
   connectionClosed: boolean;        // Flag to prevent multiple cleanup attempts
   cleanupTimer?: NodeJS.Timeout;    // Timer for max lifetime/inactivity
   lastActivity: number;             // Last activity timestamp for inactivity detection
+  pendingData: Buffer[];            // Buffer to hold data during connection setup
 }
 
 // Helper: Check if a port falls within any of the given port ranges
@@ -257,7 +258,8 @@ export class PortProxy {
         outgoing: null,
         incomingStartTime: Date.now(),
         lastActivity: Date.now(),
-        connectionClosed: false
+        connectionClosed: false,
+        pendingData: [] // Initialize buffer for pending data
       };
       this.connectionRecords.set(connectionId, connectionRecord);
       
@@ -391,29 +393,32 @@ export class PortProxy {
           connectionOptions.localAddress = remoteIP.replace('::ffff:', '');
         }
 
-        // Create the target socket and immediately set up data piping
+        // Temporary handler to collect data during connection setup
+        const tempDataHandler = (chunk: Buffer) => {
+          connectionRecord.pendingData.push(Buffer.from(chunk));
+          this.updateActivity(connectionRecord);
+        };
+
+        // Add the temp handler to capture all incoming data during connection setup
+        socket.on('data', tempDataHandler);
+
+        // Add initial chunk to pending data if present
+        if (initialChunk) {
+          connectionRecord.pendingData.push(Buffer.from(initialChunk));
+        }
+
+        // Create the target socket but don't set up piping immediately
         const targetSocket = plugins.net.connect(connectionOptions);
         connectionRecord.outgoing = targetSocket;
         connectionRecord.outgoingStartTime = Date.now();
         
-        // Set up the pipe immediately to ensure data flows without delay
+        // Setup error handlers immediately
-        if (initialChunk) {
-          socket.unshift(initialChunk);
-        }
-        
-        socket.pipe(targetSocket);
-        targetSocket.pipe(socket);
-        
-        console.log(
-          `Connection established: ${remoteIP} -> ${targetHost}:${connectionOptions.port}` +
-          `${serverName ? ` (SNI: ${serverName})` : forcedDomain ? ` (Port-based for domain: ${forcedDomain.domains.join(', ')})` : ''}`
-        );
-
-        // Add appropriate handlers for connection management
         socket.on('error', handleError('incoming'));
         targetSocket.on('error', handleError('outgoing'));
         socket.on('close', handleClose('incoming'));
         targetSocket.on('close', handleClose('outgoing'));
+        
+        // Handle timeouts
         socket.on('timeout', () => {
           console.log(`Timeout on incoming side from ${remoteIP}`);
           if (incomingTerminationReason === null) {
@@ -435,7 +440,44 @@ export class PortProxy {
         socket.setTimeout(120000);
         targetSocket.setTimeout(120000);
         
-        // Update activity for both sockets
+        // Wait for the outgoing connection to be ready before setting up piping
+        targetSocket.once('connect', () => {
+          // Remove temporary data handler
+          socket.removeListener('data', tempDataHandler);
+          
+          // Flush all pending data to target
+          if (connectionRecord.pendingData.length > 0) {
+            const combinedData = Buffer.concat(connectionRecord.pendingData);
+            targetSocket.write(combinedData, (err) => {
+              if (err) {
+                console.log(`Error writing pending data to target: ${err.message}`);
+                return initiateCleanupOnce('write_error');
+              }
+              
+              // Now set up piping for future data
+              socket.pipe(targetSocket);
+              targetSocket.pipe(socket);
+              
+              console.log(
+                `Connection established: ${remoteIP} -> ${targetHost}:${connectionOptions.port}` +
+                `${serverName ? ` (SNI: ${serverName})` : forcedDomain ? ` (Port-based for domain: ${forcedDomain.domains.join(', ')})` : ''}`
+              );
+            });
+          } else {
+            // No pending data, so just set up piping
+            socket.pipe(targetSocket);
+            targetSocket.pipe(socket);
+            
+            console.log(
+              `Connection established: ${remoteIP} -> ${targetHost}:${connectionOptions.port}` +
+              `${serverName ? ` (SNI: ${serverName})` : forcedDomain ? ` (Port-based for domain: ${forcedDomain.domains.join(', ')})` : ''}`
+            );
+          }
+          
+          // Clear the buffer now that we've processed it
+          connectionRecord.pendingData = [];
+          
+          // Set up activity tracking
           socket.on('data', () => {
             connectionRecord.lastActivity = Date.now();
           });
@@ -444,6 +486,28 @@ export class PortProxy {
             connectionRecord.lastActivity = Date.now();
           });
           
+          // Add the renegotiation listener (we don't need setImmediate here anymore
+          // since we're already in the connect callback)
+          if (serverName) {
+            socket.on('data', (renegChunk: Buffer) => {
+              if (renegChunk.length > 0 && renegChunk.readUInt8(0) === 22) {
+                try {
+                  // Try to extract SNI from potential renegotiation
+                  const newSNI = extractSNI(renegChunk);
+                  if (newSNI && newSNI !== connectionRecord.lockedDomain) {
+                    console.log(`Rehandshake detected with different SNI: ${newSNI} vs locked ${connectionRecord.lockedDomain}. Terminating connection.`);
+                    initiateCleanupOnce('sni_mismatch');
+                  } else if (newSNI) {
+                    console.log(`Rehandshake detected with same SNI: ${newSNI}. Allowing.`);
+                  }
+                } catch (err) {
+                  console.log(`Error processing potential renegotiation: ${err}. Allowing connection to continue.`);
+                }
+              }
+            });
+          }
+        });
+
         // Initialize a cleanup timer for max connection lifetime
         if (this.settings.maxConnectionLifetime) {
           connectionRecord.cleanupTimer = setTimeout(() => {
@@ -514,27 +578,6 @@ export class PortProxy {
           connectionRecord.lockedDomain = serverName;
           console.log(`Received connection from ${remoteIP} with SNI: ${serverName}`);
           
-          // Delay adding the renegotiation listener until the next tick,
-          // so the initial ClientHello is not reprocessed.
-          setImmediate(() => {
-            socket.on('data', (renegChunk: Buffer) => {
-              if (renegChunk.length > 0 && renegChunk.readUInt8(0) === 22) {
-                try {
-                  // Try to extract SNI from potential renegotiation
-                  const newSNI = extractSNI(renegChunk);
-                  if (newSNI && newSNI !== connectionRecord.lockedDomain) {
-                    console.log(`Rehandshake detected with different SNI: ${newSNI} vs locked ${connectionRecord.lockedDomain}. Terminating connection.`);
-                    initiateCleanupOnce('sni_mismatch');
-                  } else if (newSNI) {
-                    console.log(`Rehandshake detected with same SNI: ${newSNI}. Allowing.`);
-                  }
-                } catch (err) {
-                  console.log(`Error processing potential renegotiation: ${err}. Allowing connection to continue.`);
-                }
-              }
-            });
-          });
-          
           setupConnection(serverName, chunk);
         });
       } else {