java - Android加密 "pad block corrupted"异常

Question

在这段代码中，这一行导致异常:

clearText = c.doFinal(Base64.decode(encryptedText, Base64.DEFAULT));

javax.crypto.BadPaddingException:填充 block 已损坏

我的代码来自: http://www.techrepublic.com/blog/software-engineer/attention-android-developers-keep-user-data-safe/

有什么想法吗？

    private String decrypt (String encryptedText) {
        byte[] clearText = null;
        try {
            SecretKeySpec ks = new SecretKeySpec(getKey(), "AES");
            Cipher c = Cipher.getInstance("AES");
            c.init(Cipher.DECRYPT_MODE, ks);
            clearText = c.doFinal(Base64.decode(encryptedText, Base64.DEFAULT));
            return new String(clearText, "UTF-8");
        } catch (Exception e) {
            return null;
        }
    }

详情:我也在android上加密

Answer 1

owlstead 的建议很有帮助，但对于使用中的代码时的这种情况

Android 开发者注意:保护用户数据安全 http://www.techrepublic.com/blog/software-engineer/attention-android-developers-keep-user-data-safe/

我对代码进行了一些更改，这些更改将来可能对其他人有所帮助。我完全删除了 getkey 方法。

private static String seed;

/**
 * Encrypts the text. 
 * @param clearText The text you want to encrypt
 * @return Encrypted data if successful, or null if unsucessful
 */
protected String encrypt(String clearText) {
    byte[] encryptedText = null;
    try {
        byte[] keyData = seed.getBytes();
        SecretKey ks = new SecretKeySpec(keyData, "AES");
        Cipher c = Cipher.getInstance("AES");
        c.init(Cipher.ENCRYPT_MODE, ks);
        encryptedText = c.doFinal(clearText.getBytes("UTF-8"));
        return Base64.encodeToString(encryptedText, Base64.DEFAULT);
    } catch (Exception e) {
        return null;
    }
}

/**
 * Decrypts the text
 * @param encryptedText The text you want to encrypt
 * @return Decrypted data if successful, or null if unsucessful
 */
protected String decrypt (String encryptedText) {
    byte[] clearText = null;
    try {
        byte[] keyData = seed.getBytes();
        SecretKey ks = new SecretKeySpec(keyData, "AES");
        Cipher c = Cipher.getInstance("AES");
        c.init(Cipher.DECRYPT_MODE, ks);
        clearText = c.doFinal(Base64.decode(encryptedText, Base64.DEFAULT));
        return new String(clearText, "UTF-8");
    } catch (Exception e) {
        return null;
    }
}