Method Unwrap

plugin/client.go:224–312

(stanzas []*age.Stanza)

}

func (i *Identity) Unwrap(stanzas []*age.Stanza) (fileKey []byte, err error) {
	defer func() {
		if err != nil {
			err = fmt.Errorf("%s plugin: %w", i.name, err)
		}
	}()

	conn, err := openClientConnection(i.name, "identity-v1")
	if err != nil {
		return nil, fmt.Errorf("couldn't start plugin: %w", err)
	}
	defer conn.Close()

	// Phase 1: client sends the plugin the identity string and the stanzas
	if err := writeStanza(conn, "add-identity", i.encoding); err != nil {
		return nil, err
	}
	if _, err := writeGrease(conn); err != nil {
		return nil, err
	}
	for _, rs := range stanzas {
		s := &format.Stanza{
			Type: "recipient-stanza",
			Args: append([]string{"0", rs.Type}, rs.Args...),
			Body: rs.Body,
		}
		if err := s.Marshal(conn); err != nil {
			return nil, err
		}
	}
	if err := writeStanza(conn, "done"); err != nil {
		return nil, err
	}

	// Phase 2: plugin responds with various commands and a file key
	sr := format.NewStanzaReader(bufio.NewReader(conn))
ReadLoop:
	for {
		s, err := i.ui.readStanza(i.name, sr)
		if err != nil {
			return nil, err
		}

		switch s.Type {
		case "file-key":
			if len(s.Args) != 1 {
				return nil, fmt.Errorf("malformed file-key stanza: unexpected arguments count")
			}
			n, err := strconv.Atoi(s.Args[0])
			if err != nil {
				return nil, fmt.Errorf("malformed file-key stanza: invalid index")
			}
			// We only send a single file key, so the index must be 0.
			if n != 0 {
				return nil, fmt.Errorf("malformed file-key stanza: unexpected index")
			}
			if fileKey != nil {
				return nil, fmt.Errorf("received duplicated file-key stanza")