// DecryptAsymmetricPGP decrypts an OpenPGP message using GnuPG.
func DecryptAsymmetricPGP(encryptedData []byte, passphrase string) ([]byte, error) {
// Decrypt store data
decryptionKeys, err := openpgp.ReadSecRing(GnupgSecring())
if err != nil {
return nil, err
}
plainData, err := openpgp.Decrypt(encryptedData, decryptionKeys, passphrase)
if err != nil {
return nil, err
}
return plainData, nil
}
func upgradeZeroDotThreeToNext(d []byte) ([]byte, error) {
var err error
// Assert input data are in the expected version format
validVersion := isVersionZeroDotThreeDotZero(d)
if !validVersion {
return nil, fmt.Errorf("Provided input data not matching version 0.3 format")
}
// Declaring and instanciating a type matching
// the 0.3 version store format
legacyStore := struct {
Meta map[string]interface{} `json:"_meta"`
Data map[string]interface{} `json:"data"`
}{
Meta: make(map[string]interface{}),
Data: make(map[string]interface{}),
}
// Retrieve secret ring keys from openpgp
decryptionKeys, err := openpgp.ReadSecRing(openpgp.SecringFile)
if err != nil {
return nil, err
}
// Decrypt store version 0.3 (aka legacy)
plainData, err := openpgp.Decrypt(d, decryptionKeys, GetPassphrase())
if err != nil {
return nil, err
}
// Unmarshal it's content into the legacyStore
err = json.Unmarshal(plainData, &legacyStore)
if err != nil {
return nil, err
}
// Declaring and instanciating a type matching
// the 0.4 version store format so we can inject the
// legacy data into it
newStore := struct {
Meta map[string]interface{} `json:"meta"`
Data map[string]interface{} `json:"store"`
}{
Meta: legacyStore.Meta,
Data: legacyStore.Data,
}
// Encode it in json
newStoreData, err := json.Marshal(newStore)
if err != nil {
return nil, err
}
// Retrieve legacyStore recipients
var recipients []string
for _, r := range legacyStore.Meta["recipients"].([]interface{}) {
recipients = append(recipients, r.(string))
}
// Read the public openpgp ring to retrieve the recipients public keys
encryptionKeys, err := openpgp.ReadPubRing(openpgp.PubringFile, recipients)
if err != nil {
return nil, err
}
// Encrypt the encoded newStore content
encryptedData, err := openpgp.Encrypt(newStoreData, encryptionKeys)
if err != nil {
return nil, err
}
// Declaring and instanciating a type matching
// the 0.4 version trousseau data store format
// so we can inject the encrypted store into it
newTrousseau := struct {
CryptoAlgorithm CryptoAlgorithm `json:"crypto_algorithm"`
CryptoType CryptoType `json:"crypto_type"`
Data []byte `json:"_data"`
}{
CryptoAlgorithm: GPG_ENCRYPTION,
CryptoType: ASYMMETRIC_ENCRYPTION,
Data: encryptedData,
}
// Encode the new trousseau data store
trousseau, err := json.Marshal(newTrousseau)
if err != nil {
return nil, err
}
return trousseau, nil
}