| 347 | var hostKeyMu sync.Mutex |
| 348 | |
| 349 | func hostKeyFileOrCreate(keyDir string) ([]byte, error) { |
| 350 | hostKeyMu.Lock() |
| 351 | defer hostKeyMu.Unlock() |
| 352 | |
| 353 | path := filepath.Join(keyDir, "ssh_host_ed25519_key") |
| 354 | v, err := os.ReadFile(path) |
| 355 | if err == nil { |
| 356 | return v, nil |
| 357 | } |
| 358 | if !os.IsNotExist(err) { |
| 359 | return nil, err |
| 360 | } |
| 361 | |
| 362 | _, priv, err := ed25519.GenerateKey(rand.Reader) |
| 363 | if err != nil { |
| 364 | return nil, err |
| 365 | } |
| 366 | mk, err := x509.MarshalPKCS8PrivateKey(priv) |
| 367 | if err != nil { |
| 368 | return nil, err |
| 369 | } |
| 370 | pemData := pem.EncodeToMemory(&pem.Block{Type: "PRIVATE KEY", Bytes: mk}) |
| 371 | if err := os.WriteFile(path, pemData, 0600); err != nil { |
| 372 | return nil, err |
| 373 | } |
| 374 | return pemData, nil |
| 375 | } |
| 376 | |
| 377 | // opcodeShortName maps SSH terminal mode opcodes to mnemonic names |
| 378 | // expected by the termios package. |