4

I'm attempting to store some encrypted data in the Android filesystem. I'm getting errors I don't understand and empty files. Please help.

Code:

private Cipher cipher;
private ArrayList<ConnectionProfile> connectionProfiles;

public void createCipher() throws Exception{
    cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
}

public void saveProfiles() {
    try {
        if (cipher == null) {createCipher();}
        FileOutputStream fos = openFileOutput("connProfiles.bin", Context.MODE_PRIVATE);
        BufferedOutputStream bos = new BufferedOutputStream(fos);
        CipherOutputStream cos = new CipherOutputStream(bos, cipher);
        ObjectOutputStream oos = new ObjectOutputStream(cos);
        oos.writeObject(connectionProfiles);
        oos.flush();
        oos.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public void readProfiles() {
    try {
        if (cipher == null) {createCipher();}
        FileInputStream fis = openFileInput("connProfiles.bin");
        BufferedInputStream bis = new BufferedInputStream(fis);
        CipherInputStream cis = new CipherInputStream(bis, cipher);
        ObjectInputStream ois = new ObjectInputStream(cis);
        connectionProfiles = (ArrayList<ConnectionProfile>) ois.readObject();
        ois.close();
    } catch (Exception e) {
        e.printStackTrace();
        ;
    }
}

Traceback:

05-09 23:24:39.628: W/System.err(837): java.lang.IllegalStateException
05-09 23:24:39.639: W/System.err(837):  at javax.crypto.Cipher.update(Cipher.java:884)
05-09 23:24:39.639: W/System.err(837):  at javax.crypto.CipherOutputStream.write(CipherOutputStream.java:95)
05-09 23:24:39.639: W/System.err(837):  at java.io.DataOutputStream.writeShort(DataOutputStream.java:192)
05-09 23:24:39.648: W/System.err(837):  at java.io.ObjectOutputStream.writeStreamHeader(ObjectOutputStream.java:1815)
05-09 23:24:39.648: W/System.err(837):  at java.io.ObjectOutputStream.<init>(ObjectOutputStream.java:279)
05-09 23:24:39.648: W/System.err(837):  at com.sajnasoft.down2home.MainActivity.saveProfiles(MainActivity.java:39)
05-09 23:24:39.648: W/System.err(837):  at com.sajnasoft.down2home.MainActivity$2.onClick(MainActivity.java:92)
05-09 23:24:39.658: W/System.err(837):  at android.view.View.performClick(View.java:4204)
05-09 23:24:39.658: W/System.err(837):  at android.view.View$PerformClick.run(View.java:17355)
05-09 23:24:39.658: W/System.err(837):  at android.os.Handler.handleCallback(Handler.java:725)
05-09 23:24:39.658: W/System.err(837):  at android.os.Handler.dispatchMessage(Handler.java:92)
05-09 23:24:39.658: W/System.err(837):  at android.os.Looper.loop(Looper.java:137)
05-09 23:24:39.668: W/System.err(837):  at android.app.ActivityThread.main(ActivityThread.java:5041)
05-09 23:24:39.668: W/System.err(837):  at java.lang.reflect.Method.invokeNative(Native Method)
05-09 23:24:39.668: W/System.err(837):  at java.lang.reflect.Method.invoke(Method.java:511)
05-09 23:24:39.678: W/System.err(837):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
05-09 23:24:39.678: W/System.err(837):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
05-09 23:24:39.678: W/System.err(837):  at dalvik.system.NativeStart.main(Native Method)
05-09 23:26:33.878: W/IInputConnectionWrapper(837): showStatusIcon on inactive InputConnection

Update:

So now I have

private Spinner spinner;
private SpinAdapter adapter;
private Cipher cipher;
private ArrayList<ConnectionProfile> connectionProfiles;
private KeyGenerator keygen;
private SecretKey key;

public void createCipher() throws Exception{
    cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
    keygen = KeyGenerator.getInstance("AES");
    key = keygen.generateKey();
}

public void saveProfiles() {
    try {
        if (cipher == null) {createCipher();}
        cipher.init(Cipher.ENCRYPT_MODE, key);
        FileOutputStream fos = openFileOutput("connProfiles.bin", Context.MODE_PRIVATE);
        BufferedOutputStream bos = new BufferedOutputStream(fos);
        CipherOutputStream cos = new CipherOutputStream(bos, cipher);
        ObjectOutputStream oos = new ObjectOutputStream(cos);
        oos.writeObject(connectionProfiles);
        oos.flush();
        oos.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public void readProfiles() {
    try {
        if (cipher == null) {createCipher();}
        cipher.init(Cipher.ENCRYPT_MODE, key);
        FileInputStream fis = openFileInput("connProfiles.bin");
        BufferedInputStream bis = new BufferedInputStream(fis);
        CipherInputStream cis = new CipherInputStream(bis, cipher);
        ObjectInputStream ois = new ObjectInputStream(cis);
        connectionProfiles = (ArrayList<ConnectionProfile>) ois.readObject();
        ois.close();
    } catch (Exception e) {
        e.printStackTrace();
        ;
    }
}

and:

05-11 22:20:40.658: W/System.err(1019): java.io.StreamCorruptedException
05-11 22:20:40.658: W/System.err(1019):     at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:2109)
05-11 22:20:40.658: W/System.err(1019):     at java.io.ObjectInputStream.<init>(ObjectInputStream.java:372)
05-11 22:20:40.658: W/System.err(1019):     at com.sajnasoft.down2home.MainActivity.readProfiles(MainActivity.java:59)
05-11 22:20:40.658: W/System.err(1019):     at com.sajnasoft.down2home.MainActivity.onCreate(MainActivity.java:83)
05-11 22:20:40.658: W/System.err(1019):     at android.app.Activity.performCreate(Activity.java:5104)
05-11 22:20:40.658: W/System.err(1019):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
05-11 22:20:40.668: W/System.err(1019):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
05-11 22:20:40.668: W/System.err(1019):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
05-11 22:20:40.668: W/System.err(1019):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
05-11 22:20:40.668: W/System.err(1019):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
05-11 22:20:40.668: W/System.err(1019):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-11 22:20:40.668: W/System.err(1019):     at android.os.Looper.loop(Looper.java:137)
05-11 22:20:40.668: W/System.err(1019):     at android.app.ActivityThread.main(ActivityThread.java:5041)
05-11 22:20:40.678: W/System.err(1019):     at java.lang.reflect.Method.invokeNative(Native Method)
05-11 22:20:40.678: W/System.err(1019):     at java.lang.reflect.Method.invoke(Method.java:511)
05-11 22:20:40.678: W/System.err(1019):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
05-11 22:20:40.678: W/System.err(1019):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
05-11 22:20:40.678: W/System.err(1019):     at dalvik.system.NativeStart.main(Native Method)

Alright so now I'm initializing the cipher and salt in the onCreate, and my methods have gotten significantly more complicated as follows. The end result is a corrupted stream when attempting to read.

private Spinner spinner;
private SpinAdapter adapter;
private Cipher cipher;
private ArrayList<ConnectionProfile> connectionProfiles;
private KeyGenerator keygen;
private SecretKey key;
private String salt;
private SecretKey saltedKey;
private static final String RANDOM_ALGORITHM = "SHA1PRNG";
private IvParameterSpec ivSpec;

public void createKey() throws Exception {
    keygen = KeyGenerator.getInstance("AES");
    key = keygen.generateKey();
    byte[] saltedKeyBytes = new byte[key.getEncoded().length+salt.getBytes().length];
    System.arraycopy(key.getEncoded(), 0, saltedKeyBytes, 0, key.getEncoded().length);
    System.arraycopy(salt.getBytes(), 0, saltedKeyBytes, key.getEncoded().length, salt.getBytes().length);
    saltedKey = new SecretKeySpec(saltedKeyBytes, 0, saltedKeyBytes.length, "AES");
}

 private byte[] generateIv() throws NoSuchAlgorithmException {
      SecureRandom random = SecureRandom.getInstance(RANDOM_ALGORITHM);
      byte[] iv = new byte[16];
      random.nextBytes(iv);
      return iv;
}

public void saveProfiles() {
    try {
        if (key == null) {createKey();}
        cipher.init(Cipher.ENCRYPT_MODE, saltedKey, ivSpec);
        FileOutputStream fos = openFileOutput("connProfiles.bin", Context.MODE_PRIVATE);
        BufferedOutputStream bos = new BufferedOutputStream(fos);
        CipherOutputStream cos = new CipherOutputStream(bos, cipher);
        ObjectOutputStream oos = new ObjectOutputStream(cos);
        oos.writeObject(connectionProfiles);
        oos.flush();
        oos.close();
        FileOutputStream keyOutputStream = openFileOutput("key.bin", Context.MODE_PRIVATE);
        keyOutputStream.write(key.getEncoded());
        keyOutputStream.flush();
        keyOutputStream.close();
        byte[] iv = generateIv();
        IvParameterSpec ivSpec = new IvParameterSpec(iv);
        FileOutputStream ivOutputStream = openFileOutput("iv.bin", Context.MODE_PRIVATE);
        ivOutputStream.write(iv);
        ivOutputStream.flush();
        ivOutputStream.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public void readProfiles() {
    try {
        File file = new File(this.getFilesDir(), "key.bin");
        byte[] keyBytes = new byte[(int) file.length()];
        FileInputStream keyInputStream = new FileInputStream(file);
        keyInputStream.read(keyBytes);
        keyInputStream.close();
        File file2 = new File(this.getFilesDir(), "iv.bin");
        byte[] iv = new byte[(int) file2.length()];
        FileInputStream ivInputStream = new FileInputStream(file2);
        ivInputStream.read(iv);
        ivInputStream.close();
        IvParameterSpec ivSpec = new IvParameterSpec(iv);
        byte[] saltedKeyBytes = new byte[keyBytes.length+salt.getBytes().length];
        System.arraycopy(keyBytes, 0, saltedKeyBytes, 0, keyBytes.length);
        System.arraycopy(salt.getBytes(), 0, saltedKeyBytes, keyBytes.length, salt.getBytes().length);
        saltedKey = new SecretKeySpec(saltedKeyBytes, 0, saltedKeyBytes.length, "AES");
        cipher.init(Cipher.DECRYPT_MODE, saltedKey, ivSpec);
        FileInputStream fis = openFileInput("connProfiles.bin");
        BufferedInputStream bis = new BufferedInputStream(fis);
        CipherInputStream cis = new CipherInputStream(bis, cipher);
        ObjectInputStream ois = new ObjectInputStream(cis);
        connectionProfiles = (ArrayList<ConnectionProfile>) ois.readObject();
        ois.close();
    } catch (Exception e) {
        e.printStackTrace();
        ;
    }
}

Traceback:

05-19 01:08:17.325: W/System.err(843): java.io.StreamCorruptedException
05-19 01:08:17.325: W/System.err(843):  at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:2109)
05-19 01:08:17.325: W/System.err(843):  at java.io.ObjectInputStream.<init>(ObjectInputStream.java:372)
05-19 01:08:17.335: W/System.err(843):  at com.sajnasoft.down2home.MainActivity.readProfiles(MainActivity.java:102)
05-19 01:08:17.335: W/System.err(843):  at com.sajnasoft.down2home.MainActivity.onCreate(MainActivity.java:132)
05-19 01:08:17.335: W/System.err(843):  at android.app.Activity.performCreate(Activity.java:5104)
05-19 01:08:17.335: W/System.err(843):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
05-19 01:08:17.335: W/System.err(843):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
05-19 01:08:17.335: W/System.err(843):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
05-19 01:08:17.335: W/System.err(843):  at android.app.ActivityThread.access$600(ActivityThread.java:141)
05-19 01:08:17.335: W/System.err(843):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
05-19 01:08:17.345: W/System.err(843):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-19 01:08:17.345: W/System.err(843):  at android.os.Looper.loop(Looper.java:137)
05-19 01:08:17.345: W/System.err(843):  at android.app.ActivityThread.main(ActivityThread.java:5041)
05-19 01:08:17.345: W/System.err(843):  at java.lang.reflect.Method.invokeNative(Native Method)
05-19 01:08:17.345: W/System.err(843):  at java.lang.reflect.Method.invoke(Method.java:511)
05-19 01:08:17.345: W/System.err(843):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
05-19 01:08:17.345: W/System.err(843):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
05-19 01:08:17.355: W/System.err(843):  at dalvik.system.NativeStart.main(Native Method)
4

2 回答 2

2

好吧，我得到它的工作。您没有使用正确的 ivSpec 进行密码初始化。试试这个（iv 现在是一个字段）：

public void saveProfiles() {
    try {
        if (key == null) {
            createKey();
            iv = generateIv();
            ivSpec = new IvParameterSpec(iv);
        }
        cipher.init(Cipher.ENCRYPT_MODE, saltedKey, ivSpec);
        FileOutputStream fos = openFileOutput("connProfiles.bin", Context.MODE_PRIVATE);
        BufferedOutputStream bos = new BufferedOutputStream(fos);
        CipherOutputStream cos = new CipherOutputStream(bos, cipher);
        ObjectOutputStream oos = new ObjectOutputStream(cos);
        oos.writeObject(connectionProfiles);
        oos.flush();
        oos.close();
        FileOutputStream keyOutputStream = openFileOutput("key.bin", Context.MODE_PRIVATE);
        keyOutputStream.write(key.getEncoded());
        keyOutputStream.flush();
        keyOutputStream.close();
        FileOutputStream ivOutputStream = openFileOutput("iv.bin", Context.MODE_PRIVATE);
        ivOutputStream.write(iv);
        ivOutputStream.flush();
        ivOutputStream.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

在我的测试中，我没有使用盐。如果密钥太长，这也可能会导致问题。

于 2013-05-28T11:53:04.963 回答
1

我认为问题是你忘了初始化密码：你必须告诉密码是加密还是解密：cipher.init(Cipher.DECRYPT_MODE, secKey); cipher.init(Cipher.ENCRYPT_MODE, secKey);

我认为AES需要一个密钥来加密和解密。

希望这个链接可以帮助：

http://www.flexiprovider.de/examples/ExampleCrypt.html

于 2013-05-10T00:01:04.203 回答