Method passphrasePrompt

pgp/keysource.go:543–591

passphrasePrompt prompts the user for a passphrase when this is required for encryption or decryption.

()

// passphrasePrompt prompts the user for a passphrase when this is required for
// encryption or decryption.
func (key *MasterKey) passphrasePrompt() func(keys []openpgp.Key, symmetric bool) ([]byte, error) {
	callCounter := 0
	maxCalls := 3
	return func(keys []openpgp.Key, symmetric bool) ([]byte, error) {
		if callCounter >= maxCalls {
			return nil, fmt.Errorf("function passphrasePrompt called too many times")
		}
		callCounter++

		conn, err := gpgagent.NewConn()
		if err == gpgagent.ErrNoAgent {
			log.Infof("gpg-agent not found, continuing with manual passphrase " +
				"input...")
			fmt.Print("Enter PGP key passphrase: ")
			pass, err := term.ReadPassword(int(os.Stdin.Fd()))
			if err != nil {
				return nil, err
			}
			for _, k := range keys {
				k.PrivateKey.Decrypt(pass)
			}
			return pass, err
		}
		if err != nil {
			return nil, fmt.Errorf("could not establish connection with gpg-agent: %s", err)
		}
		defer func(conn *gpgagent.Conn) {
			if err := conn.Close(); err != nil {
				log.Errorf("failed to close connection with gpg-agent: %s", err)
			}
		}(conn)

		for _, k := range keys {
			req := gpgagent.PassphraseRequest{
				CacheKey: k.PublicKey.KeyIdShortString(),
				Prompt:   "Passphrase",
				Desc:     fmt.Sprintf("Unlock key %s to decrypt sops's key", k.PublicKey.KeyIdShortString()),
			}
			pass, err := conn.GetPassphrase(&req)
			if err != nil {
				return nil, fmt.Errorf("gpg-agent passphrase request errored: %s", err)
			}
			k.PrivateKey.Decrypt([]byte(pass))
			return []byte(pass), nil
		}

		return nil, fmt.Errorf("no key to unlock")
	}
}

// loadRing attempts to load the keyring from the provided path.
// Unsupported keys are ignored as long as at least a single valid key is