Question

因此，我尝试在我的Android应用程序中实施 AES-256 加密/解密。但是，由于存在出口管制政策，我不想包含额外的jar以启用 AES-256 。

我在官方文档中找到了this，似乎<ion-content style="background-color: #f5f8fa;"> <p style="line-height:24px;padding-left:10px;margin-top:20px;text-transform:capitalize;font-size:16px;">{{this.TASKDESC}}</p> <ion-list *ngFor="let list of list; let i = index;" style="margin:0;height:auto;padding-top:5px;padding-left:17px;z-index:-1"> <ion-item text-wrap class="item" style=" margin-top:-25px;padding:0; background-color:#f5f8fa;z-index:-1;"> <div [style.margin]="list.TAG_FROM === loggedinuser ? '0px 0px 0px -12px':'0px -12px 0px 0px'" [style.float]="list.TAG_FROM === loggedinuser ? 'right':'left'" style="width:33px;height:33px;background-color:#818993;overflow:hidden;color:#fff;z-index:9.9999999;border-radius:50%;font-size:14px;text-align:center;padding-top:7px;" >{{list.TAG_FROM.substring(0,2)}}</div> </div> </ion-item> </ion-list> </ion-content>支持 AES-256 和 AES-128 ，有没有办法在较旧的API级别使用此算法？

Answer 1

Android上已支持所有版本的AES多年。您引用的策略特定于vanilla JVM，在Android上不是必需的。像这样构造你的密码对象以使用AES-256：

byte[] key = ... // Your key material, exactly 32 bytes in length.
byte[] iv = ... // A randomly generated IV, exactly 16 bytes in length.
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, new SecretKey(key, "AES"), new IvParameterSpec(iv));

Answer 2

Android支持AES-256。您可以使用此帮助程序类来简化工作。

警告：此代码不安全。它使用固定的IV和坏密钥管理实践。不要在生产中或任何需要实际安全性的物品中使用它。

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.InvalidAlgorithmParameterException;
import java.security.spec.AlgorithmParameterSpec;

public class AES256Cipher {

    public static byte[] encrypt(byte[] ivBytes, byte[] keyBytes, byte[] textBytes)
            throws java.io.UnsupportedEncodingException,
            NoSuchAlgorithmException,
            NoSuchPaddingException,
            InvalidKeyException,
            InvalidAlgorithmParameterException,
            IllegalBlockSizeException,
            BadPaddingException {

        AlgorithmParameterSpec ivSpec = new IvParameterSpec(ivBytes);
        SecretKeySpec newKey = new SecretKeySpec(keyBytes, "AES");
        Cipher cipher = null;
        cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, newKey, ivSpec);
        return cipher.doFinal(textBytes);
    }

    public static byte[] decrypt(byte[] ivBytes, byte[] keyBytes, byte[] textBytes)
            throws java.io.UnsupportedEncodingException,
            NoSuchAlgorithmException,
            NoSuchPaddingException,
            InvalidKeyException,
            InvalidAlgorithmParameterException,
            IllegalBlockSizeException,
            BadPaddingException {

        AlgorithmParameterSpec ivSpec = new IvParameterSpec(ivBytes);
        SecretKeySpec newKey = new SecretKeySpec(keyBytes, "AES");
        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, newKey, ivSpec);
        return cipher.doFinal(textBytes);
    }
}

使用

String key = "e8ffc7e56311679f12b6fc91aa77a5eb";
byte[] keyBytes = key.getBytes("UTF-8");
byte[] ivBytes = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

String plainText;
byte[] cipherData;
String base64Text;

//############## Request(crypt) ##############
plainText  = "crypt text!!";
cipherData = AES256Cipher.encrypt(ivBytes, keyBytes, plainText.getBytes("UTF-8"));
base64Text = Base64.encodeToString(cipherData, Base64.DEFAULT);
Log.d("encrypt", base64Text);   //BhSJd4mRRJo+fGzpxIOUNg==

//############## Response(decrypt) ##############
base64Text = "72XrlydqnUzVrDfDE7ncnQ==";
cipherData = AES256Cipher.decrypt(ivBytes, keyBytes, Base64.decode(base64Text.getBytes("UTF-8"), Base64.DEFAULT));
plainText = new String(cipherData, "UTF-8");
Log.d("dcrypt", plainText);

AES-256能否在API级别为26+的Android设备上运行？

2 个答案: