Android 安卓4.2破解了我的AES加密/解密代码

Android 安卓4.2破解了我的AES加密/解密代码,android,aes,Android,Aes,这是我第一次在这里寻求帮助,我的部门(一个政府部门)已经在市场上发布了一些应用程序(Google Play),直到昨天我在Nexus上得到了Jelly Bean 4.2,加密和描述都工作得很好。 encrypt工作正常,它实际上是对要存储的信息进行加密。尽管在解密它时,我得到了一个异常,就像这样:pad block corrupted。 我检查了字符串,它与其他设备上的字符串一致(使用相同的键进行测试),这意味着它完全相同。 问题是我们需要保持与以前版本的向后兼容性,这意味着如果我更改代码中的某

这是我第一次在这里寻求帮助,我的部门(一个政府部门)已经在市场上发布了一些应用程序(Google Play),直到昨天我在Nexus上得到了Jelly Bean 4.2,加密和描述都工作得很好。 encrypt工作正常,它实际上是对要存储的信息进行加密。尽管在解密它时,我得到了一个异常,就像这样:pad block corrupted。 我检查了字符串,它与其他设备上的字符串一致(使用相同的键进行测试),这意味着它完全相同。 问题是我们需要保持与以前版本的向后兼容性,这意味着如果我更改代码中的某些内容,它应该能够读取旧的加密信息。它存储在SQLite上的加密信息,因为我需要将其编码为Base64。异常发生在此行byte[]decrypted=cipher.doFinal(加密)

这是我的班级:

import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

import android.util.Base64;

public class EncodeDecodeAES {

    private final static String HEX = "0123456789ABCDEF";

    public static String encrypt(String seed, String cleartext) throws Exception {
        byte[] rawKey = getRawKey(seed.getBytes());
        byte[] result = encrypt(rawKey, cleartext.getBytes());
        String fromHex = toHex(result);
        String base64 = new String(Base64.encodeToString(fromHex.getBytes(), 0));
        return base64;
    }


    public static String decrypt(String seed, String encrypted) throws Exception {
        String base64 = new String(Base64.decode(encrypted, 0));
        byte[] rawKey = getRawKey(seed.getBytes());
        byte[] enc = toByte(base64);
        byte[] result = decrypt(rawKey, enc);
        return new String(result);
    }


    public static byte[] encryptBytes(String seed, byte[] cleartext) throws Exception {
        byte[] rawKey = getRawKey(seed.getBytes());
        byte[] result = encrypt(rawKey, cleartext);
        return result;
    }


    public static byte[] decryptBytes(String seed, byte[] encrypted) throws Exception {
        byte[] rawKey = getRawKey(seed.getBytes());
        byte[] result = decrypt(rawKey, encrypted);
        return result;
    }



    private static byte[] getRawKey(byte[] seed) throws Exception {
        KeyGenerator kgen = KeyGenerator.getInstance("AES");
        SecureRandom sr = SecureRandom.getInstance("SHA1PRNG");
        sr.setSeed(seed);
        try {
            kgen.init(256, sr);
        } catch (Exception e) {
    //      Log.w(LOG, "This device doesn't suppor 256bits, trying 192bits.");
            try {
                kgen.init(192, sr);
            } catch (Exception e1) {
    //          Log.w(LOG, "This device doesn't suppor 192bits, trying 128bits.");
                kgen.init(128, sr);
            }
        }
        SecretKey skey = kgen.generateKey();
        byte[] raw = skey.getEncoded();
        return raw;
    }


    private static byte[] encrypt(byte[] raw, byte[] clear) throws Exception {
        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
        byte[] encrypted = cipher.doFinal(clear);
        return encrypted;
    }


    private static byte[] decrypt(byte[] raw, byte[] encrypted) throws Exception {
        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
        Cipher cipher = Cipher.getInstance("AES");
        cipher.init(Cipher.DECRYPT_MODE, skeySpec);
        byte[] decrypted = cipher.doFinal(encrypted);
        return decrypted;
    }


    public static String toHex(String txt) {
        return toHex(txt.getBytes());
    }


    public static String fromHex(String hex) {
        return new String(toByte(hex));
    }


    public static byte[] toByte(String hexString) {
        int len = hexString.length() / 2;
        byte[] result = new byte[len];
        for (int i = 0; i < len; i++)
            result[i] = Integer.valueOf(hexString.substring(2 * i, 2 * i + 2), 16).byteValue();
        return result;
    }


    public static String toHex(byte[] buf) {
        if (buf == null)
            return "";
        StringBuffer result = new StringBuffer(2 * buf.length);
        for (int i = 0; i < buf.length; i++) {
            appendHex(result, buf[i]);
        }
        return result.toString();
    }


    private static void appendHex(StringBuffer sb, byte b) {
        sb.append(HEX.charAt((b >> 4) & 0x0f)).append(HEX.charAt(b & 0x0f));
    }

}
导入java.security.SecureRandom;
导入javax.crypto.Cipher;
导入javax.crypto.KeyGenerator;
导入javax.crypto.SecretKey;
导入javax.crypto.spec.SecretKeySpec;
导入android.util.Base64;
公共类编码{
私有最终静态字符串HEX=“0123456789ABCDEF”;
公共静态字符串加密(字符串种子、字符串明文)引发异常{
byte[]rawKey=getRawKey(seed.getBytes());
byte[]result=encrypt(rawKey,cleartext.getBytes());
字符串fromHex=toHex(结果);
String base64=新字符串(base64.encodeToString(fromHex.getBytes(),0));
返回base64;
}
公共静态字符串解密(字符串种子、字符串加密)引发异常{
String base64=新字符串(base64.decode(加密,0));
byte[]rawKey=getRawKey(seed.getBytes());
字节[]enc=toByte(base64);
字节[]结果=解密(rawKey,enc);
返回新字符串(结果);
}
公共静态字节[]encryptBytes(字符串种子,字节[]明文)引发异常{
byte[]rawKey=getRawKey(seed.getBytes());
字节[]结果=加密(rawKey,明文);
返回结果;
}
公共静态字节[]解密字节(字符串种子,字节[]加密)引发异常{
byte[]rawKey=getRawKey(seed.getBytes());
字节[]结果=解密(rawKey,加密);
返回结果;
}
私有静态字节[]getRawKey(字节[]种子)引发异常{
KeyGenerator kgen=KeyGenerator.getInstance(“AES”);
SecureRandom sr=SecureRandom.getInstance(“SHA1PRNG”);
高级种子(种子);
试一试{
千克初始值(256,sr);
}捕获(例外e){
//w(Log,“此设备不支持256位,尝试192位。”);
试一试{
kgen.init(192,sr);
}捕获(异常e1){
//w(Log,“此设备不支持192位,尝试128位。”);
kgen.init(128,sr);
}
}
SecretKey skey=kgen.generateKey();
字节[]原始=skey.getEncoded();
返回原材料;
}
私有静态字节[]加密(字节[]原始,字节[]清除)引发异常{
SecretKeySpec skeySpec=新SecretKeySpec(原始,“AES”);
Cipher Cipher=Cipher.getInstance(“AES”);
cipher.init(cipher.ENCRYPT_模式,skeySpec);
字节[]加密=cipher.doFinal(清除);
返回加密;
}
私有静态字节[]解密(字节[]原始,字节[]加密)引发异常{
SecretKeySpec skeySpec=新SecretKeySpec(原始,“AES”);
Cipher Cipher=Cipher.getInstance(“AES”);
cipher.init(cipher.DECRYPT_模式,skeySpec);
字节[]解密=cipher.doFinal(加密);
返回解密;
}
公共静态字符串toHex(字符串txt){
返回到hex(txt.getBytes());
}
公共静态字符串fromHex(字符串十六进制){
返回新字符串(toByte(hex));
}
公共静态字节[]toByte(字符串hexString){
int len=hexString.length()/2;
字节[]结果=新字节[len];
对于(int i=0;i>4)和0x0f)).append(十六进制字符(b和0x0f));
}
}
我想知道(如果有人帮助我),我在这段代码上做错了什么,或者这是否是安卓4.2的问题,是否是安卓4.2的问题,如果有任何解决方法


谢谢

您可以尝试使用SpongyCastle图书馆。 这是一个在Android上编译的BouncyCastle

由于它与BouncyCastle兼容(只有包名和服务提供商不同,“SC”而不是“BC”),并且Android使用BouncyCastle的一个子集,因此在代码中集成SpongyCastle应该是一项简单的任务

您可以在这里找到SpongyCastle:

注意注册SpongyCastle,如其网站所述:

static {
    Security.addProvider(new org.spongycastle.jce.provider.BouncyCastleProvider());
}

获取加密对象实例时,请同时指定提供程序(“SC”)。

警告此答案使用
SecureRandom
进行密钥派生,这与其用途相反
SecureRandom
是一个随机数生成器,不能保证在平台之间产生一致的输出(这就是问题的原因)。密钥派生的正确机制是
SecretKeyFactory
。这篇文章对这个问题有很好的评论。此答案为受向后兼容性限制的情况提供了解决方案
    package au.gov.dhsJobSeeker.main.readwriteprefssettings.util;

    import java.security.SecureRandom;

    import javax.crypto.Cipher;
    import javax.crypto.KeyGenerator;
    import javax.crypto.SecretKey;
    import javax.crypto.spec.SecretKeySpec;

    import android.util.Base64;

    public class EncodeDecodeAES {

private final static String HEX = "0123456789ABCDEF";
private final static int JELLY_BEAN_4_2 = 17;
private final static byte[] key = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };


// static {
// Security.addProvider(new BouncyCastleProvider());
// }

public static String encrypt(String seed, String cleartext) throws Exception {
    byte[] rawKey = getRawKey(seed.getBytes());
    byte[] result = encrypt(rawKey, cleartext.getBytes());
    String fromHex = toHex(result);
    String base64 = new String(Base64.encodeToString(fromHex.getBytes(), 0));
    return base64;
}


public static String decrypt(String seed, String encrypted) throws Exception {
    byte[] seedByte = seed.getBytes();
    System.arraycopy(seedByte, 0, key, 0, ((seedByte.length < 16) ? seedByte.length : 16));
    String base64 = new String(Base64.decode(encrypted, 0));
    byte[] rawKey = getRawKey(seedByte);
    byte[] enc = toByte(base64);
    byte[] result = decrypt(rawKey, enc);
    return new String(result);
}


public static byte[] encryptBytes(String seed, byte[] cleartext) throws Exception {
    byte[] rawKey = getRawKey(seed.getBytes());
    byte[] result = encrypt(rawKey, cleartext);
    return result;
}


public static byte[] decryptBytes(String seed, byte[] encrypted) throws Exception {
    byte[] rawKey = getRawKey(seed.getBytes());
    byte[] result = decrypt(rawKey, encrypted);
    return result;
}


private static byte[] getRawKey(byte[] seed) throws Exception {
    KeyGenerator kgen = KeyGenerator.getInstance("AES"); // , "SC");
    SecureRandom sr = null;
    if (android.os.Build.VERSION.SDK_INT >= JELLY_BEAN_4_2) {
        sr = SecureRandom.getInstance("SHA1PRNG", "Crypto");
    } else {
        sr = SecureRandom.getInstance("SHA1PRNG");
    }
    sr.setSeed(seed);
    try {
        kgen.init(256, sr);
        // kgen.init(128, sr);
    } catch (Exception e) {
        // Log.w(LOG, "This device doesn't suppor 256bits, trying 192bits.");
        try {
            kgen.init(192, sr);
        } catch (Exception e1) {
            // Log.w(LOG, "This device doesn't suppor 192bits, trying 128bits.");
            kgen.init(128, sr);
        }
    }
    SecretKey skey = kgen.generateKey();
    byte[] raw = skey.getEncoded();
    return raw;
}


private static byte[] encrypt(byte[] raw, byte[] clear) throws Exception {
    SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
    Cipher cipher = Cipher.getInstance("AES"); // /ECB/PKCS7Padding", "SC");
    cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
    byte[] encrypted = cipher.doFinal(clear);
    return encrypted;
}


private static byte[] decrypt(byte[] raw, byte[] encrypted) throws Exception {
    SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
    Cipher cipher = Cipher.getInstance("AES"); // /ECB/PKCS7Padding", "SC");
    cipher.init(Cipher.DECRYPT_MODE, skeySpec);
    byte[] decrypted = cipher.doFinal(encrypted);
    return decrypted;
}


public static String toHex(String txt) {
    return toHex(txt.getBytes());
}


public static String fromHex(String hex) {
    return new String(toByte(hex));
}


public static byte[] toByte(String hexString) {
    int len = hexString.length() / 2;
    byte[] result = new byte[len];
    for (int i = 0; i < len; i++)
        result[i] = Integer.valueOf(hexString.substring(2 * i, 2 * i + 2), 16).byteValue();
    return result;
}


public static String toHex(byte[] buf) {
    if (buf == null) return "";
    StringBuffer result = new StringBuffer(2 * buf.length);
    for (int i = 0; i < buf.length; i++) {
        appendHex(result, buf[i]);
    }
    return result.toString();
}


private static void appendHex(StringBuffer sb, byte b) {
    sb.append(HEX.charAt((b >> 4) & 0x0f)).append(HEX.charAt(b & 0x0f));
}

    }