clearsign.Decode
// Decode finds the first clearsigned message in data and returns it, as well as
// the suffix of data which remains after the message. Any prefix data is
// discarded.
//
// If no message is found, or if the message is invalid, Decode returns nil and
// the whole data slice. The only allowed header type is Hash, and it is not
// verified against the signature hash.
func Decode(data []byte) (b *Block, rest []byte)
clearsign.Encode
// Encode returns a WriteCloser which will clear-sign a message with privateKey
// and write it to w. If config is nil, sensible defaults are used.
func Encode(w io.Writer, privateKey *packet.PrivateKey, config *packet.Config) (plaintext io.WriteCloser, err error)
clearsign.EncodeMulti
// EncodeMulti returns a WriteCloser which will clear-sign a message with all the
// private keys indicated and write it to w. If config is nil, sensible defaults
// are used.
func EncodeMulti(w io.Writer, privateKeys []*packet.PrivateKey, config *packet.Config) (plaintext io.WriteCloser, err error)