I try to obtain a pair of key (public and private) to encrypt/decrypt text. For encryption no problems. For decryption I'va an error from one day and I don't understand why.
This is the relevant part of code:
static void createKey(Context context) {
try {
KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSA", "AndroidKeyStore");
Calendar start = Calendar.getInstance(Locale.ITALIAN);
Calendar end = Calendar.getInstance(Locale.ITALIAN);
end.add(Calendar.YEAR, 10);
AlgorithmParameterSpec spec = null;
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
spec = new KeyPairGeneratorSpec.Builder(context)
.setAlias(BuildConfig.APPLICATION_ID)
.setSubject(new X500Principal("CN=Sample Name, O=Android Authority"))
.setSerialNumber(BigInteger.ONE)
//.setStartDate(start.getTime())
//.setEndDate(end.getTime())
.build();
} else {
spec = new KeyGenParameterSpec.Builder(BuildConfig.APPLICATION_ID,KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_DECRYPT)
.setCertificateSubject(new X500Principal("CN=Sample Name, O=Android Authority"))
.setDigests(KeyProperties.DIGEST_SHA256)
.setSignaturePaddings(KeyProperties.SIGNATURE_PADDING_RSA_PKCS1)
.setCertificateSerialNumber(BigInteger.valueOf(1337))
.setCertificateNotBefore(start.getTime())
.setCertificateNotAfter(end.getTime())
.setRandomizedEncryptionRequired(false)
.build();
}
kpg.initialize(spec);
KeyPair kp = kpg.generateKeyPair();
// END_INCLUDE(create_spec)
Log.d(TAG, "createKey Public Key is: " + kp.getPublic());
Log.d(TAG, "createKey Private Key is: " + kp.getPrivate());
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
} catch (NoSuchProviderException e) {
e.printStackTrace();
} catch (InvalidAlgorithmParameterException e) {
e.printStackTrace();
}
}
public static String encrypt(Context context, String text) {
if(text == null || text.isEmpty()) {
return null;
}
KeyStore keyStore = null;
try {
keyStore = KeyStore.getInstance("AndroidKeyStore");
keyStore.load(null);
PublicKey publicKey = keyStore.getCertificate(BuildConfig.APPLICATION_ID).getPublicKey();
Cipher input = getCipher();
input.init(Cipher.ENCRYPT_MODE, publicKey);//, ivspec);
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
CipherOutputStream cipherOutputStream = new CipherOutputStream(
outputStream, input);
cipherOutputStream.write(text.getBytes("UTF-8"));
cipherOutputStream.close();
byte [] vals = outputStream.toByteArray();
return Base64.encodeToString(vals, Base64.DEFAULT);
} catch (Exception e) {
Log.e(TAG, Log.getStackTraceString(e));
}
return null;
}
public static String decrypt(Context context, String encryptedText) {
KeyStore keyStore = null;
try {
keyStore = KeyStore.getInstance("AndroidKeyStore");
keyStore.load(null);
KeyStore.Entry entry = keyStore.getEntry(BuildConfig.APPLICATION_ID, null);
PrivateKey privateKey = ((KeyStore.PrivateKeyEntry) entry).getPrivateKey();
PublicKey publicKey = keyStore.getCertificate(BuildConfig.APPLICATION_ID).getPublicKey();
Cipher output = getCipher();
output.init(Cipher.DECRYPT_MODE, privateKey);//, ivspec);
CipherInputStream cipherInputStream = new CipherInputStream(
new ByteArrayInputStream(Base64.decode(encryptedText, Base64.DEFAULT)), output);
ArrayList<Byte> values = new ArrayList<>();
int nextByte;
while ((nextByte = cipherInputStream.read()) != -1) {
values.add((byte)nextByte);
}
byte[] bytes = new byte[values.size()];
for(int i = 0; i < bytes.length; i++) {
bytes[i] = values.get(i).byteValue();
}
return new String(bytes, 0, bytes.length, "UTF-8");
} catch (Exception e) {
Log.e(TAG, Log.getStackTraceString(e));
}
return null;
}
static Cipher getCipher() throws Exception {
return Cipher.getInstance("RSA/ECB/PKCS1Padding");
}
The exception is throwed when I call output.init(Cipher.DECRYPT_MODE, privateKey); in decrypt method and is:
05-17 16:52:02.334 31384-31384/ E/Utils: java.security.InvalidKeyException: Keystore operation failed
at android.security.KeyStore.getInvalidKeyException(KeyStore.java:733)
at android.security.KeyStore.getInvalidKeyException(KeyStore.java:754)
at android.security.keystore.KeyStoreCryptoOperationUtils.getInvalidKeyExceptionForInit(KeyStoreCryptoOperationUtils.java:54)
at android.security.keystore.KeyStoreCryptoOperationUtils.getExceptionForCipherInit(KeyStoreCryptoOperationUtils.java:89)
at android.security.keystore.AndroidKeyStoreCipherSpiBase.ensureKeystoreOperationInitialized(AndroidKeyStoreCipherSpiBase.java:265)
at android.security.keystore.AndroidKeyStoreCipherSpiBase.engineInit(AndroidKeyStoreCipherSpiBase.java:109)
at javax.crypto.Cipher.tryTransformWithProvider(Cipher.java:2977)
at javax.crypto.Cipher.tryCombinations(Cipher.java:2884)
at javax.crypto.Cipher$SpiAndProviderUpdater.updateAndGetSpiAndProvider(Cipher.java:2789)
at javax.crypto.Cipher.chooseProvider(Cipher.java:956)
at javax.crypto.Cipher.init(Cipher.java:1199)
at javax.crypto.Cipher.init(Cipher.java:1143)
at it.a.b.utils.Utils.decrypt(Utils.java:249)
at it.a.b.activities.LoginActivity.onCreate(LoginActivity.java:90)
at android.app.Activity.performCreate(Activity.java:6910)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2746)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2864)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1567)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:156)
at android.app.ActivityThread.main(ActivityThread.java:6577)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:941)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:831)
Caused by: android.security.KeyStoreException: -65530
at android.security.KeyStore.getKeyStoreException(KeyStore.java:672)
at android.security.KeyStore.getInvalidKeyException(KeyStore.java:754)
at android.security.keystore.KeyStoreCryptoOperationUtils.getInvalidKeyExceptionForInit(KeyStoreCryptoOperationUtils.java:54)
at android.security.keystore.KeyStoreCryptoOperationUtils.getExceptionForCipherInit(KeyStoreCryptoOperationUtils.java:89)
at android.security.keystore.AndroidKeyStoreCipherSpiBase.ensureKeystoreOperationInitialized(AndroidKeyStoreCipherSpiBase.java:265)
at android.security.keystore.AndroidKeyStoreCipherSpiBase.engineInit(AndroidKeyStoreCipherSpiBase.java:109)
at javax.crypto.Cipher.tryTransformWithProvider(Cipher.java:2977)
at javax.crypto.Cipher.tryCombinations(Cipher.java:2884)
at javax.crypto.Cipher$SpiAndProviderUpdater.updateAndGetSpiAndProvider(Cipher.java:2789)
at javax.crypto.Cipher.chooseProvider(Cipher.java:956)
at javax.crypto.Cipher.init(Cipher.java:1199)
at javax.crypto.Cipher.init(Cipher.java:1143)
at it.a.b.utils.Utils.decrypt(Utils.java:249)
at it.a.b.activities.LoginActivity.onCreate(LoginActivity.java:90)
at android.app.Activity.performCreate(Activity.java:6910)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2746)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2864)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1567)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:156)
at android.app.ActivityThread.main(ActivityThread.java:6577)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:941)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:831)
Have you any idea about this?
