feat: inner tunnel for TTSL support added

src/auth.ts

@@ -18,6 +18,7 @@ export class Authentication implements IAuthentication {
 		}
 
 		const authResult = await this.authenticator.authenticate(username, password);
+		console.log(`Auth Result for user ${username}`, authResult ? 'SUCCESS' : 'Failure');
 		this.cache.set(cacheKey, authResult, 86400); // cache for one day
 
 		return authResult;

src/auth/GoogleLDAPAuth.ts

@@ -113,7 +113,7 @@ export class GoogleLDAPAuth implements IAuthentication {
 			if (!dnsFetched && !forceFetching) {
 				return this.authenticate(username, password, count, true);
 			}
-			console.error(`invalid username, not found in DN: ${username}`, this.allValidDNsCache);
+			console.error(`invalid username, not found in DN: ${username}`); // , this.allValidDNsCache);
 			return false;
 		}
 

src/radius/RadiusService.ts

@@ -4,11 +4,21 @@ import { EAPPacketHandler } from './handler/EAPPacketHandler';
 import { DefaultPacketHandler } from './handler/DefaultPacketHandler';
 import { IPacketHandler, IPacketHandlerResult, PacketResponseCode } from '../types/PacketHandler';
 
+import { EAPTTLS } from './handler/eap/eapMethods/EAP-TTLS';
+import { EAPMD5 } from './handler/eap/eapMethods/EAP-MD5';
+import { EAPGTC } from './handler/eap/eapMethods/EAP-GTC';
+
 export class RadiusService {
 	radiusPacketHandlers: IPacketHandler[] = [];
 
 	constructor(private secret: string, private authentication: IAuthentication) {
-		this.radiusPacketHandlers.push(new EAPPacketHandler(authentication));
+		this.radiusPacketHandlers.push(
+			new EAPPacketHandler([
+				new EAPTTLS(authentication),
+				new EAPGTC(authentication),
+				new EAPMD5(authentication)
+			])
+		);
 		this.radiusPacketHandlers.push(new DefaultPacketHandler(authentication));
 	}
 

src/radius/handler/EAPPacketHandler.ts

@@ -3,103 +3,21 @@
 import * as NodeCache from 'node-cache';
 import { RadiusPacket } from 'radius';
 import debug from 'debug';
-import { EAPTTLS } from './eapMethods/EAPTTLS';
 import { makeid } from '../../helpers';
-import {
-	IPacketHandler,
-	IPacketHandlerResult,
-	PacketResponseCode
-} from '../../types/PacketHandler';
-import { IAuthentication } from '../../types/Authentication';
+import { IPacketHandler, IPacketHandlerResult } from '../../types/PacketHandler';
 import { IEAPMethod } from '../../types/EAPMethod';
+import { buildEAPResponse, decodeEAPHeader } from './eap/EAPHelper';
 
 const log = debug('radius:eap');
 
 export class EAPPacketHandler implements IPacketHandler {
-	private eapMethods: IEAPMethod[] = [];
-
 	// 	private eapConnectionStates: { [key: string]: { validMethods: IEAPMethod[] } } = {};
 	private eapConnectionStates = new NodeCache({ useClones: false, stdTTL: 3600 }); // max for one hour
 
-	constructor(authentication: IAuthentication) {
-		this.eapMethods.push(new EAPTTLS(authentication));
-	}
-
-	/**
-	 *
-	 * @param data
-	 * @param msgType 1 = identity, 21 = EAP-TTLS, 2 = notification, 4 = md5-challenge, 3 = NAK
-	 */
-	private async buildEAPResponse(
-		identifier: number,
-		msgType: number,
-		data?: Buffer
-	): Promise<IPacketHandlerResult> {
-		/** build a package according to this:
-			0                   1                   2                   3
-			0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
-		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-		 |     Code      |  Identifier   |            Length             |
-		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-		 |     Type      |  Type-Data ...
-		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
-		 */
-		const buffer = Buffer.from([
-			1, // request
-			identifier,
-			0, // length (1/2)
-			0, //  length (2/2)
-			msgType // 1 = identity, 21 = EAP-TTLS, 2 = notificaiton, 4 = md5-challenge, 3 = NAK
-		]);
-
-		const resBuffer = data ? Buffer.concat([buffer, data]) : buffer;
-		// set EAP length header
-		resBuffer.writeUInt16BE(resBuffer.byteLength, 2);
-
-		return {
-			code: PacketResponseCode.AccessChallenge,
-			attributes: [['EAP-Message', buffer]]
-		};
-	}
-
-	private decodeEAPHeader(msg: Buffer) {
-		/**
-		 * parse msg according to this:
-		  0                   1                   2                   3
-			0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
-		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-		 |     Code      |  Identifier   |            Length             |
-		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-		 |     Type      |  Type-Data ...
-		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
-		 */
-
-		/*
-		code:
-        1       Request
-        2       Response
-        3       Success
-        4       Failure
-         */
-		const code = msg.slice(0, 1).readUInt8(0);
-		/* identifier is a number */
-		const identifier = msg.slice(1, 2).readUInt8(0);
-		const length = msg.slice(2, 4).readInt16BE(0);
-		/* EAP type */
-		const type = msg.slice(4, 5).readUInt8(0);
-		const data = msg.slice(5);
-
-		return {
-			code,
-			identifier,
-			length,
-			type,
-			data
-		};
-	}
+	constructor(private eapMethods: IEAPMethod[]) {}
 
 	async handlePacket(
-		attributes: { [key: string]: Buffer },
+		attributes: { [key: string]: Buffer | string },
 		orgRadiusPacket: RadiusPacket
 	): Promise<IPacketHandlerResult> {
 		if (!attributes['EAP-Message']) {
@@ -116,9 +34,9 @@ export class EAPPacketHandler implements IPacketHandler {
 		}
 
 		// EAP MESSAGE
-		const msg = attributes['EAP-Message'];
+		const msg = attributes['EAP-Message'] as Buffer;
 
-		const { code, type, identifier, data } = this.decodeEAPHeader(msg);
+		const { code, type, identifier, data } = decodeEAPHeader(msg);
 
 		const currentState = this.eapConnectionStates.get(stateID) as { validMethods: IEAPMethod[] };
 
@@ -130,10 +48,10 @@ export class EAPPacketHandler implements IPacketHandler {
 						log('>>>>>>>>>>>> REQUEST FROM CLIENT: IDENTIFY', {});
 						// start identify
 						if (currentState.validMethods.length > 0) {
-							return currentState.validMethods[0].identify(identifier, stateID);
+							return currentState.validMethods[0].identify(identifier, stateID, data);
 						}
 
-						return this.buildEAPResponse(identifier, 3);
+						return buildEAPResponse(identifier, 3); // NAK
 					case 2: // notification
 						log('>>>>>>>>>>>> REQUEST FROM CLIENT: notification', {});
 						console.info('notification');
@@ -180,7 +98,7 @@ export class EAPPacketHandler implements IPacketHandler {
 
 						console.error('unsupported type', type, `requesting: ${serverSupportedMethods}`);
 
-						return this.buildEAPResponse(identifier, 3, Buffer.from(serverSupportedMethods));
+						return buildEAPResponse(identifier, 3, Buffer.from(serverSupportedMethods));
 					}
 				}
 				break;

src/radius/handler/eap/EAPHelper.ts

@@ -0,0 +1,79 @@
+import { IPacketHandlerResult, PacketResponseCode } from '../../../types/PacketHandler';
+
+export function buildEAP(identifier: number, msgType: number, data?: Buffer) {
+	/** build a package according to this:
+			0                   1                   2                   3
+			0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+		 |     Code      |  Identifier   |            Length             |
+		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+		 |     Type      |  Type-Data ...
+		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
+	 */
+	const buffer = Buffer.from([
+		1, // request
+		identifier,
+		0, // length (1/2)
+		0, //  length (2/2)
+		msgType // 1 = identity, 21 = EAP-TTLS, 2 = notificaiton, 4 = md5-challenge, 3 = NAK
+	]);
+
+	const resBuffer = data ? Buffer.concat([buffer, data]) : buffer;
+
+	// set EAP length header
+	resBuffer.writeUInt16BE(resBuffer.byteLength, 2);
+
+	return resBuffer;
+}
+
+/**
+ *
+ * @param data
+ * @param msgType 1 = identity, 21 = EAP-TTLS, 2 = notification, 4 = md5-challenge, 3 = NAK
+ */
+export function buildEAPResponse(
+	identifier: number,
+	msgType: number,
+	data?: Buffer
+): IPacketHandlerResult {
+	return {
+		code: PacketResponseCode.AccessChallenge,
+		attributes: [['EAP-Message', buildEAP(identifier, msgType, data)]]
+	};
+}
+
+export function decodeEAPHeader(msg: Buffer) {
+	/**
+	 * parse msg according to this:
+		  0                   1                   2                   3
+			0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+		 |     Code      |  Identifier   |            Length             |
+		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+		 |     Type      |  Type-Data ...
+		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
+	 */
+
+	/*
+	code:
+			1       Request
+			2       Response
+			3       Success
+			4       Failure
+			 */
+	const code = msg.slice(0, 1).readUInt8(0);
+	/* identifier is a number */
+	const identifier = msg.slice(1, 2).readUInt8(0);
+	const length = msg.slice(2, 4).readUInt16BE(0);
+	/* EAP type */
+	const type = msg.slice(4, 5).readUInt8(0);
+	const data = msg.slice(5);
+
+	return {
+		code,
+		identifier,
+		length,
+		type,
+		data
+	};
+}

src/radius/handler/eap/eapMethods/EAP-GTC.ts

@@ -0,0 +1,65 @@
+// https://tools.ietf.org/html/rfc5281 TTLS v0
+// https://tools.ietf.org/html/draft-funk-eap-ttls-v1-00 TTLS v1 (not implemented)
+/* eslint-disable no-bitwise */
+import * as NodeCache from 'node-cache';
+import debug from 'debug';
+import { IPacketHandlerResult, PacketResponseCode } from '../../../../types/PacketHandler';
+import { IEAPMethod } from '../../../../types/EAPMethod';
+import { IAuthentication } from '../../../../types/Authentication';
+import { buildEAPResponse, decodeEAPHeader } from '../EAPHelper';
+
+const log = debug('radius:eap:gtc');
+
+export class EAPGTC implements IEAPMethod {
+	private loginData = new NodeCache({ useClones: false, stdTTL: 60 }); // queue data maximum for 60 seconds
+
+	getEAPType(): number {
+		return 6;
+	}
+
+	identify(identifier: number, stateID: string, msg?: Buffer): IPacketHandlerResult {
+		if (msg) {
+			const parsedMsg = msg.slice(
+				0,
+				msg.findIndex(v => v === 0)
+			);
+			log('identify', parsedMsg, parsedMsg.toString());
+			this.loginData.set(stateID, parsedMsg); // use token til binary 0.);
+		} else {
+			log('no msg');
+		}
+
+		return buildEAPResponse(identifier, 6, Buffer.from('Password: '));
+	}
+
+	constructor(private authentication: IAuthentication) {}
+
+	async handleMessage(
+		_identifier: number,
+		stateID: string,
+		msg: Buffer
+	): Promise<IPacketHandlerResult> {
+		const username = this.loginData.get(stateID) as Buffer | undefined;
+
+		const { data } = decodeEAPHeader(msg);
+
+		let tillBinary0 = data.findIndex(v => v === 0) || data.length;
+		if (tillBinary0 < 0) {
+			tillBinary0 = data.length - 1;
+		}
+		const token = data.slice(0, tillBinary0 + 1); // use token til binary 0.
+
+		if (!username) {
+			throw new Error('no username');
+		}
+
+		log('username', username, username.toString());
+		log('token', token, token.toString());
+
+		const success = await this.authentication.authenticate(username.toString(), token.toString());
+
+		return {
+			code: success ? PacketResponseCode.AccessAccept : PacketResponseCode.AccessReject
+		};
+	}
+}

src/radius/handler/eap/eapMethods/EAP-MD5.ts

@@ -0,0 +1,40 @@
+// https://tools.ietf.org/html/rfc5281 TTLS v0
+// https://tools.ietf.org/html/draft-funk-eap-ttls-v1-00 TTLS v1 (not implemented)
+/* eslint-disable no-bitwise */
+import { RadiusPacket } from 'radius';
+import debug from 'debug';
+import { ResponseAuthHandler } from '../../../../types/Handler';
+import { IPacketHandlerResult } from '../../../../types/PacketHandler';
+import { IEAPMethod } from '../../../../types/EAPMethod';
+import { IAuthentication } from '../../../../types/Authentication';
+
+const log = debug('radius:eap:md5');
+
+interface IEAPResponseHandlers {
+	response: (respData?: Buffer, msgType?: number) => void;
+	checkAuth: ResponseAuthHandler;
+}
+
+export class EAPMD5 implements IEAPMethod {
+	getEAPType(): number {
+		return 4;
+	}
+
+	identify(_identifier: number, _stateID: string): IPacketHandlerResult {
+		// NOT IMPLEMENTED
+		return {};
+	}
+
+	constructor(private authentication: IAuthentication) {}
+
+	async handleMessage(
+		_identifier: number,
+		_stateID: string,
+		_msg: Buffer,
+		_orgRadiusPacket: RadiusPacket
+	): Promise<IPacketHandlerResult> {
+		// not implemented
+
+		return {};
+	}
+}

src/radius/handler/eap/eapMethods/EAP-TTLS.ts

@@ -1,19 +1,20 @@
 // https://tools.ietf.org/html/rfc5281 TTLS v0
 // https://tools.ietf.org/html/draft-funk-eap-ttls-v1-00 TTLS v1 (not implemented)
-
 /* eslint-disable no-bitwise */
 import * as tls from 'tls';
 import * as NodeCache from 'node-cache';
 import { RadiusPacket } from 'radius';
 import debug from 'debug';
-import { encodeTunnelPW, ITLSServer, startTLSServer } from '../../../tls/crypt';
-import { ResponseAuthHandler } from '../../../types/Handler';
+import { encodeTunnelPW, ITLSServer, startTLSServer } from '../../../../tls/crypt';
+import { ResponseAuthHandler } from '../../../../types/Handler';
 import { PAPChallenge } from './challenges/PAPChallenge';
-import { IPacketHandlerResult, PacketResponseCode } from '../../../types/PacketHandler';
-import { MAX_RADIUS_ATTRIBUTE_SIZE, newDeferredPromise } from '../../../helpers';
-import { IEAPMethod } from '../../../types/EAPMethod';
-import { IAuthentication } from '../../../types/Authentication';
-import { secret } from '../../../../config';
+import { IPacketHandlerResult, PacketResponseCode } from '../../../../types/PacketHandler';
+import { MAX_RADIUS_ATTRIBUTE_SIZE, newDeferredPromise } from '../../../../helpers';
+import { IEAPMethod } from '../../../../types/EAPMethod';
+import { IAuthentication } from '../../../../types/Authentication';
+import { secret } from '../../../../../config';
+import { EAPPacketHandler } from '../../EAPPacketHandler';
+import { EAPGTC } from './EAP-GTC';
 
 const log = debug('radius:eap:ttls');
 
@@ -38,6 +39,9 @@ export class EAPTTLS implements IEAPMethod {
 
 	private openTLSSockets = new NodeCache({ useClones: false, stdTTL: 3600 }); // keep sockets for about one hour
 
+	// EAP TUNNEL
+	tunnelEAP = new EAPPacketHandler([new EAPGTC(this.authentication)]); // tunnel with GTC support
+
 	getEAPType(): number {
 		return 21;
 	}
@@ -48,23 +52,23 @@ export class EAPTTLS implements IEAPMethod {
 
 	constructor(private authentication: IAuthentication) {}
 
-	private buildEAPTTLSResponse(
+	private buildEAPTTLS(
 		identifier: number,
 		msgType = 21,
 		msgFlags = 0x00,
 		stateID: string,
 		data?: Buffer,
-		newResponse = true
-	): IPacketHandlerResult {
-		const maxSize = (MAX_RADIUS_ATTRIBUTE_SIZE - 5) * 4;
+		newResponse = true,
+		maxSize = (MAX_RADIUS_ATTRIBUTE_SIZE - 5) * 4
+	): Buffer {
 		log('maxSize', maxSize);
 
 		/* it's the first one and we have more, therefore include length */
-		const includeLength = data && newResponse && data.length > maxSize;
+		const includeLength = maxSize > 0 && data && newResponse && data.length > maxSize;
 
 		// extract data party
-		const dataToSend = data && data.length > 0 && data.slice(0, maxSize);
-		const dataToQueue = data && data.length > maxSize && data.slice(maxSize);
+		const dataToSend = maxSize > 0 ? data && data.length > 0 && data.slice(0, maxSize) : data;
+		const dataToQueue = maxSize > 0 && data && data.length > maxSize && data.slice(maxSize);
 
 		/*
 			0 1 2 3 4 5 6 7 8
@@ -129,6 +133,19 @@ export class EAPTTLS implements IEAPMethod {
 			this.queueData.del(stateID);
 		}
 
+		return resBuffer;
+	}
+
+	private buildEAPTTLSResponse(
+		identifier: number,
+		msgType = 21,
+		msgFlags = 0x00,
+		stateID: string,
+		data?: Buffer,
+		newResponse = true
+	): IPacketHandlerResult {
+		const resBuffer = this.buildEAPTTLS(identifier, msgType, msgFlags, stateID, data, newResponse);
+
 		const attributes: any = [['State', Buffer.from(stateID)]];
 		let sentDataSize = 0;
 		do {
@@ -162,7 +179,7 @@ export class EAPTTLS implements IEAPMethod {
 		 Message Length         |             Data...
 		 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 		 */
-
+		const identifier = msg.slice(1, 2).readUInt8(0);
 		const flags = msg.slice(5, 6).readUInt8(0); // .toString('hex');
 		/*
 			0   1   2   3   4   5   6   7
@@ -191,10 +208,19 @@ export class EAPTTLS implements IEAPMethod {
 
 		let msglength;
 		if (decodedFlags.lengthIncluded) {
-			msglength = msg.slice(6, 10).readInt32BE(0); // .readDoubleLE(0); // .toString('hex');
+			msglength = msg.slice(6, 10).readUInt32BE(0); // .readDoubleLE(0); // .toString('hex');
 		}
 		const data = msg.slice(decodedFlags.lengthIncluded ? 10 : 6, msg.length);
 
+		log('>>>>>>>>>>>> REQUEST FROM CLIENT: EAP TTLS', {
+			flags: `00000000${flags.toString(2)}`.substr(-8),
+			decodedFlags,
+			identifier,
+			msglength,
+			data
+			// dataStr: data.toString()
+		});
+
 		return {
 			decodedFlags,
 			msglength,
@@ -255,13 +281,10 @@ export class EAPTTLS implements IEAPMethod {
 		msg: Buffer,
 		orgRadiusPacket: RadiusPacket
 	): Promise<IPacketHandlerResult> {
-		const { decodedFlags, msglength, data } = this.decodeTTLSMessage(msg);
+		const { data } = this.decodeTTLSMessage(msg);
 
 		// check if no data package is there and we have something in the queue, if so.. empty the queue first
 		if (!data || data.length === 0) {
-			log(
-				`>>>>>>>>>>>> REQUEST FROM CLIENT: EAP TTLS, ACK / NACK (no data, just a confirmation, ID: ${identifier})`
-			);
 			const queuedData = this.queueData.get(stateID);
 			if (queuedData instanceof Buffer && queuedData.length > 0) {
 				return this.buildEAPTTLSResponse(identifier, 21, 0x00, stateID, queuedData, false);
@@ -270,15 +293,6 @@ export class EAPTTLS implements IEAPMethod {
 			return {};
 		}
 
-		log('>>>>>>>>>>>> REQUEST FROM CLIENT: EAP TTLS', {
-			// flags: `00000000${flags.toString(2)}`.substr(-8),
-			decodedFlags,
-			identifier,
-			msglength
-			// data,
-			// dataStr: data.toString()
-		});
-
 		let connection = this.openTLSSockets.get(stateID) as ITLSServer;
 
 		if (!connection) {
@@ -295,11 +309,18 @@ export class EAPTTLS implements IEAPMethod {
 		const sendResponsePromise = newDeferredPromise();
 
 		const incomingMessageHandler = async (incomingData: Buffer) => {
-			const type = incomingData.slice(3, 4).readUInt8(0);
+			const ret: any = {};
+			ret.attributes = {};
+			ret.raw_attributes = [];
+
+			const { type, data: AVPdata, length: AVPlength } = this.decodeAVP(incomingData);
+
+			console.log('AVP data', { AVPdata, AVPlength, AVPdataStr: AVPdata.toString() });
+
 			// const code = data.slice(4, 5).readUInt8(0);
 
 			switch (type) {
-				case 1: // PAP / CHAP
+				case 1: // PAP
 					try {
 						const { username, password } = this.papChallenge.decode(incomingData);
 						const authResult = await this.authentication.authenticate(username, password);
@@ -315,17 +336,51 @@ export class EAPTTLS implements IEAPMethod {
 						sendResponsePromise.resolve(this.buildEAPTTLSResponse(identifier, 3, 0, stateID));
 					}
 					break;
-				default:
+				case 79: {
+					const result = await this.tunnelEAP.handlePacket(
+						{
+							State: `${stateID}-inner`,
+							'EAP-Message': AVPdata
+						},
+						orgRadiusPacket
+					);
+
+					log('inner tunnel result', result);
+
+					if (
+						result.code === PacketResponseCode.AccessReject ||
+						result.code === PacketResponseCode.AccessAccept
+					) {
+						sendResponsePromise.resolve(
+							this.authResponse(
+								identifier,
+								result.code === PacketResponseCode.AccessAccept,
+								connection.tls,
+								orgRadiusPacket
+							)
+						);
+						return;
+					}
+
+					const eapMessage = result.attributes?.find(attr => attr[0] === 'EAP-Message');
+					if (!eapMessage) {
+						throw new Error('no eap message found');
+					}
+
+					connection.events.emit('encrypt', this.buildAVP(79, eapMessage[1]));
+					break;
+				}
+				default: {
 					log('data', incomingData);
 					log('data str', incomingData.toString());
 
-					// currentConnection!.events.emit('end');
+					log('UNSUPPORTED AUTH TYPE, requesting identify again (we need PAP!)', type);
 
-					log('UNSUPPORTED AUTH TYPE, requesting PAP');
-					// throw new Error(`unsupported auth type${type}`);
-					sendResponsePromise.resolve(
-						this.buildEAPTTLSResponse(identifier, 3, 0, stateID, Buffer.from([1]))
+					connection.events.emit(
+						'encrypt',
+						this.buildAVP(79, this.buildEAPTTLS(identifier, 3, 0, stateID, Buffer.from([1])))
 					);
+				}
 			}
 		};
 
@@ -341,7 +396,7 @@ export class EAPTTLS implements IEAPMethod {
 		connection.events.on('response', responseHandler);
 
 		// emit data to tls server
-		connection.events.emit('send', data);
+		connection.events.emit('decrypt', data);
 		const responseData = await sendResponsePromise.promise;
 
 		// cleanup
@@ -351,4 +406,114 @@ export class EAPTTLS implements IEAPMethod {
 		// send response
 		return responseData; // this.buildEAPTTLSResponse(identifier, 21, 0x00, stateID, encryptedResponseData);
 	}
+
+	private decodeAVP(buffer: Buffer) {
+		/**
+		 * 4.1.  AVP Header
+
+						 The fields in the AVP header MUST be sent in network byte order.  The
+						 format of the header is:
+
+							0                   1                   2                   3
+							0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+						 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+						 |                           AVP Code                            |
+						 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+						 |V M P r r r r r|                  AVP Length                   |
+						 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+						 |                        Vendor-ID (opt)                        |
+						 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+						 |    Data ...
+						 +-+-+-+-+-+-+-+-+
+		 */
+		const type = buffer.slice(0, 4).readUInt32BE(0);
+		const flags = buffer.slice(4, 5).readUInt8(0);
+		const decodedFlags = {
+			// L
+			V: !!(flags & 0b10000000),
+			// M
+			M: !!(flags & 0b01000000)
+		};
+
+		// const length = buffer.slice(5, 8).readUInt16BE(0); // actually a Int24BE
+		const length = buffer.slice(6, 8).readUInt16BE(0); // actually a Int24BE
+
+		let vendorId;
+		let data;
+		if (flags & 0b010000000) {
+			// V flag set
+			vendorId = buffer.slice(8, 12).readUInt32BE(0);
+			data = buffer.slice(8, 12);
+		} else {
+			data = buffer.slice(8);
+		}
+
+		return {
+			type,
+			flags: `00000000${flags.toString(2)}`.substr(-8),
+			decodedFlags,
+			length,
+			vendorId,
+			data
+		};
+	}
+
+	private buildAVP(
+		code: number,
+		data: Buffer,
+		flags: { VendorSpecific?: boolean; Mandatory?: boolean } = { Mandatory: true }
+	) {
+		/**
+		 * 4.1.  AVP Header
+
+						 The fields in the AVP header MUST be sent in network byte order.  The
+						 format of the header is:
+
+							0                   1                   2                   3
+							0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+						 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+						 |                           AVP Code                            |
+						 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+						 |V M r r r r r r|                  AVP Length                   |
+						 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+						 |                        Vendor-ID (opt)                        |
+						 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+						 |    Data ...
+						 +-+-+-+-+-+-+-+-+
+		 */
+		let b = Buffer.alloc(8);
+
+		b.writeInt32BE(code, 0); // EAP-Message
+		/**
+		 * The 'V' (Vendor-Specific) bit indicates whether the optional
+      Vendor-ID field is present.  When set to 1, the Vendor-ID field is
+      present and the AVP Code is interpreted according to the namespace
+      defined by the vendor indicated in the Vendor-ID field.
+
+      The 'M' (Mandatory) bit indicates whether support of the AVP is
+      required.  If this bit is set to 0, this indicates that the AVP
+      may be safely ignored if the receiving party does not understand
+      or support it.  If set to 1, this indicates that the receiving
+      party MUST fail the negotiation if it does not understand the AVP;
+      for a TTLS server, this would imply returning EAP-Failure, for a
+      client, this would imply abandoning the negotiation.
+		 */
+		let flagValue = 0;
+		if (flags.VendorSpecific) {
+			flagValue += 0b10000000;
+		}
+		if (flags.Mandatory) {
+			flagValue += 0b01000000;
+		}
+
+		console.log('flagValue', flagValue, `00000000${flagValue.toString(2)}`.substr(-8));
+
+		b.writeInt8(flagValue, 4); // flags (set V..)
+
+		b = Buffer.concat([b, data]); // , Buffer.from('\0')]);
+
+		b.writeInt16BE(b.byteLength, 6); // write size (actually we would need a Int24BE here, but it is good to go with 16bits)
+
+		return b;
+	}
 }

src/radius/handler/eap/eapMethods/challenges/PAPChallenge.ts

@@ -1,5 +1,5 @@
 import debug from 'debug';
-import { IEAPChallenge } from '../../../../types/EAPChallenge';
+import { IEAPChallenge } from '../../../../../types/EAPChallenge';
 
 const log = debug('radius:eap:papchallenge');
 

src/tls/crypt.ts

@@ -42,11 +42,16 @@ export function startTLSServer(): ITLSServer {
 	});
 	const encrypted = duplexpair.socket2;
 
-	emitter.on('send', (data: Buffer) => {
+	emitter.on('decrypt', (data: Buffer) => {
 		encrypted.write(data);
 		// encrypted.sync();
 	});
 
+	emitter.on('encrypt', (data: Buffer) => {
+		cleartext.write(data);
+		// encrypted.sync();
+	});
+
 	encrypted.on('data', (data: Buffer) => {
 		// log('encrypted data', data, data.toString());
 		emitter.emit('response', data);

src/types/EAPChallenge.ts

@@ -1,3 +1,3 @@
 export interface IEAPChallenge {
-	decode(data: Buffer): { username: string; password: string };
+	decode(data: Buffer, stateID: string): { username: string; password?: string };
 }

src/types/EAPMethod.ts

@@ -4,7 +4,7 @@ import { IPacketHandlerResult } from './PacketHandler';
 export interface IEAPMethod {
 	getEAPType(): number;
 
-	identify(identifier: number, stateID: string): IPacketHandlerResult;
+	identify(identifier: number, stateID: string, msg?: Buffer): IPacketHandlerResult;
 
 	handleMessage(
 		identifier: number,