Javascript application for fuzzing

[turalsalamov]

It is a nodejs javascript demo application with vulnerability for fuzzing. Details of application are described in README.md file.

[0xricksanchez]

Suggested change

	## TODO application
	### Usage of application
	## Functionality

[0xricksanchez]

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	# Nodejs JS demo application
	# NodeJS demo application

[0xricksanchez]

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	It is simple nodejs express TODO application which has several functionalities, such as, adding,
	It is simple nodeJS express TODO application, which has several functionalities, such as, adding,

[0xricksanchez]

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	deleting, listing TODOs, deleting whole json file and command execution in the server. The application creates
	deleting single TODOs, and listing TODOs. Additional functionality includes, deleting the whole TODO list json file and command execution on the server. The application creates

[0xricksanchez]

Suggested change

	todo.json file in the root folder of the application.
	a `todo.json` file in the root folder of the application as a database to save all added TODOs.

[0xricksanchez]

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	Endpoints:
	`/api/add?todo=<todo>&deadline=<deadline>`
	`/api/delete?id=<id>`
	`/api/list`
	`/api/deleteList`
	`/api/server?command=<command>`
	Available endpoints:

/api/add?todo=&deadline=
/api/delete?id=
/api/list
/api/deleteList
/api/server?command=

[0xricksanchez]

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	"description": "Nodejs Javascript tutorial example",
	"description": "NodeJS tutorial example",

[0xricksanchez]

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	"name": "nodejs",
	"name": "TODO list server",

[0xricksanchez]

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	const fs = require('fs')
	const child_process = require('child_process')
	class TODO {
	id
	todo
	deadline
	constructor(id, todo, deadline) {
	this.id = id;
	this.todo = todo
	this.deadline = deadline
	}
	}
	function fileIsPresent() {
	return fs.existsSync('./todo.json');
	}
	function writeToFile(data) {
	try{
	fs.writeFileSync("./todo.json", JSON.stringify(data));
	}catch (e) {
	throw new Error()
	}
	}
	function readFromFile() {
	try {
	return fs.readFileSync('./todo.json');
	} catch (e) {
	throw new Error()
	}
	}
	function createAndWrite(dataToWrite){
	let initial_arr = []
	dataToWrite.id = 1
	initial_arr.push(dataToWrite)
	writeToFile(initial_arr);
	}
	function deleteEntry(id) {
	try {
	if (fileIsPresent()) {
	const temp = readFromFile();
	let content = JSON.parse(temp.toString());
	let _index = -1;
	content.forEach((element, index) => {
	if (String(element.id) === id) {
	_index = index;
	}
	});
	if (_index >= 0) {
	content.splice(_index, 1);
	writeToFile(content);
	} else {
	throw new Error();
	}
	} else {
	throw new Error();
	}
	}catch (e) {
	return false;
	}
	return true;
	}
	function addEntry(dataToWrite) {
	try{
	if (fileIsPresent()) {
	const data = readFromFile();
	let content = JSON.parse(data.toString());
	if (content.length > 0) {
	let last_id = content[content.length - 1].id
	dataToWrite.id = last_id + 1
	content.push(dataToWrite);
	writeToFile(content);
	} else {
	createAndWrite(dataToWrite)
	}
	} else {
	createAndWrite(dataToWrite)
	}
	}catch (e) {
	return false
	}
	return true
	}
	function deleteFile() {
	try {
	if (fileIsPresent()) {
	fs.unlink('./todo.json', (err) => {
	if (err) throw new Error()
	})
	return true;
	}
	return false;
	}catch (e) {
	return false;
	}
	}
	function listFile() {
	if (fileIsPresent()) {
	// read the file
	const data = readFromFile();
	const content = JSON.parse(data.toString());
	let respond = "";
	content.forEach((element) => respond = respond + "Id: " + element.id + "\tTODO: " + element.todo + "\tDeadline: " + element.deadline + "\n");
	return[true, respond]
	}
	return [false, null]
	}
	function commandExecution(command, fn) {
	child_process.exec(command, (err, stdout, stderr) => {
	fn(stdout)
	});
	}
	module.exports = {TODO, commandExecution, addEntry, deleteEntry, deleteFile, listFile}
	const fs = require('fs');
	const child_process = require('child_process')
	class TODO {
	constructor(id, todo, deadline) {
	this.id = id;
	this.todo = todo;
	this.deadline = deadline;
	}
	}
	const filePath = './todo.json';
	function fileIsPresent() {
	return fs.existsSync(filePath);
	}
	function writeToFile(data) {
	try {
	fs.writeFileSync(filePath, JSON.stringify(data));
	} catch (e) {
	console.error('Error while writing to file:', e);
	}
	}
	function readFromFile() {
	try {
	return JSON.parse(fs.readFileSync(filePath).toString());
	} catch (e) {
	console.error('Error while reading from file:', e);
	}
	return null;
	}
	function createAndWrite(dataToWrite) {
	dataToWrite.id = 1;
	writeToFile([dataToWrite]);
	}
	function deleteEntry(id) {
	if (fileIsPresent()) {
	let content = readFromFile();
	if (content) {
	let index = content.findIndex(element => element.id === id);
	if (index >= 0) {
	content.splice(index, 1);
	writeToFile(content);
	return true;
	}
	}
	}
	return false;
	}
	function addEntry(dataToWrite) {
	if (fileIsPresent()) {
	let content = readFromFile();
	if (content) {
	let lastId = content[content.length - 1].id;
	dataToWrite.id = lastId + 1;
	content.push(dataToWrite);
	writeToFile(content);
	return true;
	}
	} else {
	createAndWrite(dataToWrite);
	return true;
	}
	return false;
	}
	function deleteFile() {
	try {
	if (fileIsPresent()) {
	fs.unlinkSync(filePath);
	return true;
	}
	} catch (e) {
	console.error('Error while deleting file:', e);
	}
	return false;
	}
	function listFile() {
	if (fileIsPresent()) {
	const content = readFromFile();
	if (content) {
	return content.map(element => `Id: ${element.id}\tTODO: ${element.todo}\tDeadline: ${element.deadline}`).join('\n');
	}
	}
	return null;
	}
	function commandExecution(command, fn) {
	child_process.exec(command, (err, stdout, stderr) => {
	fn(stdout)
	});
	}
	module.exports = { TODO, addEntry, deleteEntry, deleteFile, listFile, commandExecution }

That should be more aligned with modern JavaScript.

[0xricksanchez]

JS comments also apply to the TS side. I'll leave adding these to the TS side to you @turalsalamov

[0roman]

Add an entry in the README for the new tutorials.