commandValidator.ts•3.14 kB
import { spawn, SpawnOptions } from 'child_process';
import path from 'path';
import { RegexValidator } from './regexValidator.js';
const ALLOWED_COMMANDS: Record<string, string[]> = {
// SECURITY FIX: Added 'clone' command to git allowlist
// Previously: npm installation feature would fail with "Argument not allowed: clone"
// Now: git clone command is allowed for npm installation functionality
git: ['pull', 'status', 'log', 'rev-parse', 'branch', 'checkout', 'fetch', 'clone', '--abbrev-ref', 'HEAD', '--porcelain'],
npm: ['install', 'run', 'audit', 'ci', '--version', 'build'],
node: ['--version'],
npx: ['--version']
};
export class CommandValidator {
static sanitizeCommand(cmd: string, args: string[]): void {
if (!ALLOWED_COMMANDS[cmd]) {
throw new Error(`Command not allowed: ${cmd}`);
}
const allowedArgs = ALLOWED_COMMANDS[cmd];
for (const arg of args) {
// Check if it's in allowed list or matches safe pattern
if (!allowedArgs.includes(arg) && !this.isSafeArgument(arg)) {
throw new Error(`Argument not allowed: ${arg}`);
}
}
}
private static isSafeArgument(arg: string): boolean {
// Allow alphanumeric, dash, underscore, dot, and forward slash
return RegexValidator.validate(arg, /^[a-zA-Z0-9\-_.\/]+$/, { maxLength: 1000 });
}
static async secureExec(command: string, args: string[], options?: SpawnOptions): Promise<string> {
this.sanitizeCommand(command, args);
const safeOptions: SpawnOptions = {
...options,
stdio: ['ignore', 'pipe', 'pipe'],
env: {
...process.env,
PATH: '/usr/bin:/bin:/usr/local/bin' // Restrict PATH
},
cwd: options?.cwd || process.cwd(),
timeout: options?.timeout || 30000 // 30 second default
};
return new Promise((resolve, reject) => {
const proc = spawn(command, args, safeOptions);
let stdout = '';
let stderr = '';
let timeoutHandle: NodeJS.Timeout | undefined;
let isCompleted = false;
// Helper to safely resolve/reject only once
const complete = (fn: () => void) => {
if (!isCompleted) {
isCompleted = true;
if (timeoutHandle) {
clearTimeout(timeoutHandle);
}
fn();
}
};
// Handle timeout
if (options?.timeout) {
timeoutHandle = setTimeout(() => {
proc.kill('SIGTERM');
complete(() => reject(new Error(`Command timed out after ${options.timeout}ms`)));
}, options.timeout);
timeoutHandle.unref();
}
proc.stdout?.on('data', (data) => stdout += data);
proc.stderr?.on('data', (data) => stderr += data);
proc.on('exit', (code) => {
if (code === 0) {
complete(() => resolve(stdout.trim()));
} else {
complete(() => reject(new Error(`Command failed (${code}): ${stderr}`)));
}
});
proc.on('error', (error) => {
complete(() => reject(error instanceof Error ? error : new Error(String(error))));
});
});
}
}