feat: ssh default public/key related operation

* if default private/public key exist
* get default private/public key or their path
* create new default SSH key

src/utils.ts

@@ -1,6 +1,13 @@
 import { exec } from 'child_process';
 import * as http from 'http';
 import * as https from 'https';
+import * as fs from 'fs';
+import * as path from 'path';
+import * as os from 'os';
+import { BlobOptions } from 'buffer';
+const {
+  generateKeyPairSync,
+} = require('node:crypto')
 
 export function fetch(url: string): Promise<string> {
     // determine the library to use (based on the url protocol)
@@ -52,3 +59,63 @@ export function getVsCodeCommitId(): Promise<string> {
     });
   })
 }
+
+export function getDefaultPrivateKeyPath() : string{
+    return path.join(os.homedir(), '.ssh', 'id_rsa')
+}
+
+export function getDefaultPublicKeyPath() :string{
+    return path.join(os.homedir(), '.ssh', 'id_rsa.pub')
+}
+
+export function existDefaultPublicKey() :boolean{
+    const defaultPublicKeyPath = getDefaultPublicKeyPath();
+    return fs.existsSync(defaultPublicKeyPath)
+}
+
+export function existDefaultPrivateKey() :boolean{
+    const defaultPrivateKeyPath = getDefaultPrivateKeyPath();
+    return fs.existsSync(defaultPrivateKeyPath)
+}
+
+export function getDefaultPublicKey(): string {
+    const defaultPublicKeyPath = getDefaultPublicKey();
+    return fs.readFileSync(defaultPublicKeyPath, 'utf-8');
+
+}
+
+export function getDefaultPrivateKey(): string {
+    const defaultPrivateKey = getDefaultPrivateKeyPath();
+    return fs.readFileSync(defaultPrivateKey, 'utf-8');
+}
+
+export function createSSHKey() {
+    if (!existDefaultPublicKey() || existDefaultPrivateKey()) {
+        // if public or private key exists, stop
+        return;
+    }
+
+    const {
+      publicKey,
+      privateKey,
+    } = generateKeyPairSync('rsa', {
+      modulusLength: 4096,
+      publicKeyEncoding: {
+        type: 'spki',
+        format: 'pem',
+      },
+      privateKeyEncoding: {
+        type: 'pkcs8',
+        format: 'pem',
+        cipher: 'aes-256-cbc',
+        passphrase: 'devstar'
+      },
+    });
+
+    try {
+      fs.writeFileSync(getDefaultPublicKeyPath(), publicKey);
+      fs.writeFileSync(getDefaultPrivateKeyPath(), privateKey);
+    } catch(error) {
+      console.error("Failed to write public/private key into the default ssh public/key file: ", error);
+    }
+}