fix: include instance name in Login7 message and traceID in prelogin

src/connection.ts

@@ -873,6 +873,7 @@ export interface ConnectionOptions {
 interface RoutingData {
   server: string;
   port: number;
+  instance: string;
 }
 
 /**
@@ -2484,7 +2485,7 @@ class Connection extends EventEmitter {
     }
 
     payload.hostname = this.config.options.workstationId || os.hostname();
-    payload.serverName = this.routingData ? this.routingData.server : this.config.server;
+    payload.serverName = this.routingData ? `${this.routingData.server}\\${this.routingData.instance}` : this.config.server;
     payload.appName = this.config.options.appName || 'Tedious';
     payload.libraryName = libraryName;
     payload.language = this.config.options.language;

src/login7-payload.ts

@@ -251,15 +251,12 @@ class Login7Payload {
     }
 
     // (ibUnused / ibExtension): 2-byte
-    offset = fixedData.writeUInt16LE(dataOffset, offset);
+    const extensionOffsetHeaderOffset = offset;
+    offset = fixedData.writeUInt16LE(0, offset);
+
 
     // (cchUnused / cbExtension): 2-byte
-    const extensions = this.buildFeatureExt();
     offset = fixedData.writeUInt16LE(4, offset);
-    const extensionOffset = Buffer.alloc(4);
-    extensionOffset.writeUInt32LE(dataOffset += 4, 0);
-    dataOffset += extensions.length;
-    buffers.push(extensionOffset, extensions);
 
     // ibCltIntName: 2-byte
     offset = fixedData.writeUInt16LE(dataOffset, offset);
@@ -365,6 +362,13 @@ class Login7Payload {
       fixedData.writeUInt32LE(0, offset);
     }
 
+    fixedData.writeUInt16LE(dataOffset, extensionOffsetHeaderOffset);
+
+    const extensions = this.buildFeatureExt();
+    const extensionOffset = Buffer.alloc(4);
+    extensionOffset.writeUInt32LE(dataOffset + 4, 0);
+    buffers.push(extensionOffset, extensions);
+
     const data = Buffer.concat(buffers);
     data.writeUInt32LE(data.length, 0);
     return data;

src/prelogin-payload.ts

@@ -1,15 +1,18 @@
 import { sprintf } from 'sprintf-js';
 
 import WritableTrackingBuffer from './tracking-buffer/writable-tracking-buffer';
+import { randomBytes } from 'crypto';
 
 const optionBufferSize = 20;
+const traceIdSize = 36;
 
 const TOKEN = {
   VERSION: 0x00,
   ENCRYPTION: 0x01,
   INSTOPT: 0x02,
   THREADID: 0x03,
   MARS: 0x04,
+  TRACEID: 0x05,
   FEDAUTHREQUIRED: 0x06,
   TERMINATOR: 0xFF
 };
@@ -73,6 +76,9 @@ class PreloginPayload {
 
   declare mars: number;
   declare marsString: string;
+
+  declare traceId: Buffer;
+
   declare fedAuthRequired: number;
 
   constructor(bufferOrOptions: Buffer | Options = { encrypt: false, version: { major: 0, minor: 0, build: 0, subbuild: 0 } }) {
@@ -93,6 +99,7 @@ class PreloginPayload {
       this.createInstanceOption(),
       this.createThreadIdOption(),
       this.createMarsOption(),
+      this.createTraceIdOption(),
       this.createFedAuthOption()
     ];
 
@@ -171,6 +178,17 @@ class PreloginPayload {
     };
   }
 
+  createTraceIdOption() {
+    const buffer = new WritableTrackingBuffer(traceIdSize);
+    // generate a random series of bytes to use as the TraceID
+    // used for debugging purposes
+    buffer.writeBuffer(randomBytes(traceIdSize));
+    return {
+      token: TOKEN.TRACEID,
+      data: buffer.data
+    };
+  }
+
   createFedAuthOption() {
     const buffer = new WritableTrackingBuffer(optionBufferSize);
     buffer.writeUInt8(0x01);
@@ -203,6 +221,9 @@ class PreloginPayload {
         case TOKEN.MARS:
           this.extractMars(dataOffset);
           break;
+        case TOKEN.TRACEID:
+          this.extractTraceId(dataOffset);
+          break;
         case TOKEN.FEDAUTHREQUIRED:
           this.extractFedAuth(dataOffset);
           break;
@@ -239,20 +260,25 @@ class PreloginPayload {
     this.marsString = marsByValue[this.mars];
   }
 
+  extractTraceId(offset: number) {
+    this.traceId = this.data.subarray(offset, traceIdSize);
+  }
+
   extractFedAuth(offset: number) {
     this.fedAuthRequired = this.data.readUInt8(offset);
   }
 
   toString(indent = '') {
     return indent + 'PreLogin - ' + sprintf(
-      'version:%d.%d.%d.%d, encryption:0x%02X(%s), instopt:0x%02X, threadId:0x%08X, mars:0x%02X(%s)',
+      'version:%d.%d.%d.%d, encryption:0x%02X(%s), instopt:0x%02X, threadId:0x%08X, mars:0x%02X(%s), traceId:%s',
       this.version.major, this.version.minor, this.version.build, this.version.subbuild,
       this.encryption ? this.encryption : 0,
       this.encryptionString ? this.encryptionString : '',
       this.instance ? this.instance : 0,
       this.threadId ? this.threadId : 0,
       this.mars ? this.mars : 0,
-      this.marsString ? this.marsString : ''
+      this.marsString ? this.marsString : '',
+      this.traceId ? this.traceId.toString('hex') : '',
     );
   }
 }

src/token/handler.ts

@@ -246,7 +246,7 @@ export class Login7TokenHandler extends TokenHandler {
   declare connection: Connection;
 
   declare fedAuthInfoToken: FedAuthInfoToken | undefined;
-  declare routingData: { server: string, port: number } | undefined;
+  declare routingData: { server: string, port: number, instance: string } | undefined;
 
   declare loginAckReceived: boolean;
 
@@ -337,10 +337,10 @@ export class Login7TokenHandler extends TokenHandler {
 
   onRoutingChange(token: RoutingEnvChangeToken) {
     // Removes instance name attached to the redirect url. E.g., redirect.db.net\instance1 --> redirect.db.net
-    const [ server ] = token.newValue.server.split('\\');
+    const [ server, instance ] = token.newValue.server.split('\\');
 
     this.routingData = {
-      server, port: token.newValue.port
+      server, port: token.newValue.port, instance
     };
   }