func ExampleNewEncryptArmor62Stream() {
var err error
// Make a new Keyring, initialized to be empty
keyring := basic.NewKeyring()
// The test message
plaintext := "The Magic Words are Squeamish Ossifrage"
// Make a secret key for the sender
var sender saltpack.BoxSecretKey
sender, err = keyring.GenerateBoxKey()
if err != nil {
return
}
// And one for the receiver
var receiver saltpack.BoxSecretKey
receiver, err = keyring.GenerateBoxKey()
if err != nil {
return
}
// AllReceivers can contain more receivers (like the sender)
// but for now, just the one.
var output bytes.Buffer
allReceivers := []saltpack.BoxPublicKey{receiver.GetPublicKey()}
var input io.WriteCloser
input, err = saltpack.NewEncryptArmor62Stream(&output, sender, allReceivers, "")
if err != nil {
return
}
// Write plaintext into the returned WriteCloser stream
input.Write([]byte(plaintext))
// And close when we're done
input.Close()
// The decrypted message
var plaintextOutput io.Reader
_, plaintextOutput, _, err = saltpack.NewDearmor62DecryptStream(&output, keyring)
if err != nil {
return
}
// Copy all of the data out of the output decrypted stream, and into standard
// output, here for testing / comparison purposes.
io.Copy(os.Stdout, plaintextOutput)
os.Stdout.Write([]byte{'\n'})
// Output:
// The Magic Words are Squeamish Ossifrage
}
func SaltpackDecrypt(
g *GlobalContext, source io.Reader, sink io.WriteCloser,
deviceEncryptionKey NaclDHKeyPair,
checkSender func(*saltpack.MessageKeyInfo) error) (*saltpack.MessageKeyInfo, error) {
sc, newSource, err := ClassifyStream(source)
if err != nil {
return nil, err
}
if sc.Format != CryptoMessageFormatSaltpack {
return nil, WrongCryptoFormatError{
Wanted: CryptoMessageFormatSaltpack,
Received: sc.Format,
Operation: "decrypt",
}
}
source = newSource
var mki *saltpack.MessageKeyInfo
var plainsource io.Reader
var frame saltpack.Frame
if sc.Armored {
mki, plainsource, frame, err = saltpack.NewDearmor62DecryptStream(source, naclKeyring(deviceEncryptionKey))
} else {
mki, plainsource, err = saltpack.NewDecryptStream(source, naclKeyring(deviceEncryptionKey))
}
if err != nil {
return mki, err
}
if checkSender != nil {
if err = checkSender(mki); err != nil {
return mki, err
}
}
n, err := io.Copy(sink, plainsource)
if err != nil {
return mki, err
}
// TODO: Check header inline, and only warn if the footer
// doesn't match.
if sc.Armored {
var brand string
brand, err = saltpack.CheckArmor62Frame(frame, saltpack.MessageTypeEncryption)
if err != nil {
return mki, err
}
if err = checkSaltpackBrand(brand); err != nil {
return mki, err
}
}
g.Log.Debug("Decrypt: read %d bytes", n)
if err := sink.Close(); err != nil {
return mki, err
}
return mki, nil
}