/** * lookup for the Redundant Owner (Vol.1 - Table 3-5.8 Field 15) */ const owner = { Exclusive: 0, Multiple: 1 }; /** * lookup for the Connection Type (Vol.1 - Table 3-5.8 Field 14,13) */ const connectionType = { Null: 0, Multicast: 1, PointToPoint: 2, Reserved: 3 }; /** * lookup for the Connection Priority (Vol.1 - Table 3-5.8 Field 11,10) */ const priority = { Low: 0, High: 1, Scheduled: 2, Urgent: 3 }; /** * lookup for the fixed or variable parameter (Vol.1 - Table 3-5.8 Field 9) */ const fixedVar = { Fixed: 0, Variable: 1 }; /** * Build for Object specific connection parameters (Vol.1 - Table 3-5.8) */ const build_connectionParameters = (owner: number, type: number, priority: number, fixedVar: number, size: number): number => { if (owner != 0 && owner != 1) throw new Error("Owner can only be exclusive (0) or multiple (1)"); if (type > 3 || type < 0) throw new Error("Type can only be Null(0), Multicast(1), PointToPoint(2) or Reserved(3)"); if (priority > 3 || priority < 0) throw new Error("Priority can only be Low(0), High(1), Scheduled(2) or Urgent(3)"); if (fixedVar != 0 && fixedVar !=1) throw new Error("Fixedvar can only be Fixed(0) or VariableI(1)"); if (size > 10000 || size <= 1 || typeof size !== "number") throw new Error("Size must be a positive number between 1 and 10000"); return owner << 15 | type << 13 | priority << 10 | fixedVar << 9 | size; }; /** * lookup table for Time Tick Value (Vol.1 - Table 3-5.11) */ const timePerTick = { 1 : 0 }; const connSerial = 0x1337; /** * lookup table for Timeout multiplier (Vol.1 - 3-5.4.1.4) */ const timeOutMultiplier = { 4 : 0, 8 : 1, 16: 2, 32: 3, 64: 4, 128: 5, 256: 6, 512: 7 }; type UCMMSendTimeout = { time_tick: number, ticks: number } /** * Gets the Best Available Timeout Values * * @param timeout - Desired Timeout in ms * @returns Timeout values */ const generateEncodedTimeout = (timeout: number): UCMMSendTimeout => { if (timeout <= 0 || typeof timeout !== "number") throw new Error("Timeouts Must be Positive Integers"); let diff = Infinity; // let difference be very large let time_tick = 0; let ticks = 0; // Search for Best Timeout Encoding Values for (let i = 0; i < 16; i++) { for (let j = 1; j < 256; j++) { const newDiff = Math.abs(timeout - Math.pow(2, i) * j); if (newDiff <= diff) { diff = newDiff; time_tick = i; ticks = j; } } } return { time_tick, ticks }; }; /** * Builds the data portion of a forwardOpen packet * * @param timeOutMs - How many ticks until a timeout is thrown * @param timeOutMult - A multiplier used for the Timeout * @param otRPI - O->T Request packet interval in milliseconds. * @param serialOrig - Originator Serial Number (SerNo of the PLC) * @param netConnParams - Encoded network connection parameters * @returns Data portion of the forwardOpen packet */ const build_forwardOpen = (otRPI:number = 8000, netConnParams:number = 0x43f4, timeOutMs:number = 1000 , timeOutMult:number = 32, connectionSerial:number = 0x4242, TOconnectionID:number = getRandomInt(2147483647)): Buffer => { if (timeOutMs <= 900 || typeof timeOutMs !== "number") throw new Error("Timeouts Must be Positive Integers and above 500"); if (!(timeOutMult in timeOutMultiplier) || typeof timeOutMult !== "number") throw new Error("Timeout Multiplier must be a number and a multiple of 4"); if (otRPI < 8000 || typeof otRPI !== "number") throw new Error("otRPI should be at least 8000 (8ms)"); if (typeof netConnParams !== "number") throw new Error("ConnectionParams should be created by the builder and result in a number!"); const actualMultiplier = timeOutMultiplier[timeOutMult]; const connectionParams = Buffer.alloc(35); // Normal forward open request const timeout = generateEncodedTimeout(timeOutMs); let ptr = 0; connectionParams.writeUInt8(timeout.time_tick,ptr); // Priority / TimePerTick ptr+=1; connectionParams.writeUInt8(timeout.ticks,ptr); // Timeout Ticks ptr+=1; connectionParams.writeUInt32LE(0,ptr); // O->T Connection ID ptr+=4; connectionParams.writeUInt32LE(TOconnectionID,ptr); // T->O Connection ID ptr+=4; connectionParams.writeUInt16LE(connectionSerial,ptr); // Connection Serial Number TODO: Make this unique ptr+=2; connectionParams.writeUInt16LE(0x3333,ptr); // Originator VendorID ptr+=2; connectionParams.writeUInt32LE(0x1337,ptr); // Originator Serial Number ptr+=4; connectionParams.writeUInt32LE(actualMultiplier,ptr); // TimeOut Multiplier ptr+=4; connectionParams.writeUInt32LE(otRPI,ptr); // O->T RPI ptr+=4; connectionParams.writeUInt16LE(netConnParams,ptr); // O->T Network Connection Params ptr+=2; connectionParams.writeUInt32LE(otRPI,ptr); // T->O RPI ptr+=4; connectionParams.writeUInt16LE(netConnParams,ptr); // T->O Network Connection Params ptr+=2; connectionParams.writeUInt8(0xA3,ptr); // TransportClass_Trigger (Vol.1 - 3-4.4.3) -> Target is a Server, Application object of Transport Class 3. return connectionParams; }; /** * Builds the data portion of a forwardClose packet * * @param timeOutMs - How many ms until a timeout is thrown * @param vendorOrig - Originator vendorID (Vendor of the PLC) * @param serialOrig - Originator Serial Number (SerNo of the PLC) * @param connectionSerial - Connection Serial Number * @returns Data portion of the forwardClose packet */ const build_forwardClose = (timeOutMs: number = 1000 , vendorOrig:number = 0x3333, serialOrig:number = 0x1337, connectionSerial:number = 0x4242): Buffer => { if (timeOutMs <= 900 || typeof timeOutMs !== "number") throw new Error("Timeouts Must be Positive Integers and at least 500"); if (vendorOrig <= 0 || typeof vendorOrig !== "number") throw new Error("VendorOrig Must be Positive Integers"); if (serialOrig <= 0 || typeof serialOrig !== "number") throw new Error("SerialOrig Must be Positive Integers"); const connectionParams = Buffer.alloc(10); const timeout = generateEncodedTimeout(timeOutMs); let ptr = 0; connectionParams.writeUInt8(timeout.time_tick,ptr); // Priority / TimePerTick ptr+=1; connectionParams.writeUInt8(timeout.ticks,ptr); // Timeout Ticks ptr+=1; connectionParams.writeUInt16LE(connectionSerial, ptr); // Connection Serial Number TODO: Make this unique ptr+=2; connectionParams.writeUInt16LE(vendorOrig,ptr); // Originator VendorID ptr+=2; connectionParams.writeUInt32LE(serialOrig,ptr); // Originator Serial Number return connectionParams; }; /** * Creates random integer * * @param max - Maximum value of integer * @returns random number */ function getRandomInt(max: number): number { return Math.floor(Math.random() * Math.floor(max)); } export { build_forwardOpen, build_forwardClose, build_connectionParameters, connSerial, timePerTick, timeOutMultiplier, priority, owner, connectionType, fixedVar };