public static AsymmetricMasterSecret getAsymmetricMasterSecret(
@NonNull Context context, @Nullable MasterSecret masterSecret) {
try {
byte[] djbPublicBytes = retrieve(context, ASYMMETRIC_LOCAL_PUBLIC_DJB);
byte[] djbPrivateBytes = retrieve(context, ASYMMETRIC_LOCAL_PRIVATE_DJB);
ECPublicKey djbPublicKey = null;
ECPrivateKey djbPrivateKey = null;
if (djbPublicBytes != null) {
djbPublicKey = Curve.decodePoint(djbPublicBytes, 0);
}
if (masterSecret != null) {
MasterCipher masterCipher = new MasterCipher(masterSecret);
if (djbPrivateBytes != null) {
djbPrivateKey = masterCipher.decryptKey(djbPrivateBytes);
}
}
return new AsymmetricMasterSecret(djbPublicKey, djbPrivateKey);
} catch (InvalidKeyException | IOException ike) {
throw new AssertionError(ike);
}
}
