解决IllegalBlockSizeException:last block incomplete in decryption异常

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在项目中要用到DES加密，直接使用DES加密会抛出IllegalBlockSizeException:last block incomplete in decryption异常，google后发现因为编码方式的改变，加密的时候使用DES/AES加密后需要使用Base64编码方式再进行一次加密，解密的时候需要先用Base64解密，再用DES/AES相应的方法解密。以下代码为转载，亲测可用：

package ebring.DES;import java.security.Key;import javax.crypto.Cipher;import javax.crypto.SecretKeyFactory;import javax.crypto.spec.DESedeKeySpec;import javax.crypto.spec.IvParameterSpec;import android.util.Base64;import android.util.Log;public class CryptoTools {    public static final String keyStr = "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4";    private static byte[] key=Base64.decode(keyStr.getBytes(),Base64.DEFAULT);    private static byte[] keyiv = { 1, 2, 3, 4, 5, 6, 7, 8 };    /**     * ECB加密,不要IV     * @param key 密钥     * @param data 明文     * @return Base64编码的密文     * @throws Exception     */    public static byte[] des3EncodeECB(byte[] data)            throws Exception {        Key deskey = null;        DESedeKeySpec spec = new DESedeKeySpec(key);        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");        deskey = keyfactory.generateSecret(spec);        Cipher cipher = Cipher.getInstance("desede" + "/ECB/PKCS5Padding");        cipher.init(Cipher.ENCRYPT_MODE, deskey);        byte[] bOut = cipher.doFinal(data);        return bOut;    }    /**     * ECB解密,不要IV     * @param key 密钥     * @param data Base64编码的密文     * @return 明文     * @throws Exception     */    public static byte[] ees3DecodeECB(byte[] data)            throws Exception {        Key deskey = null;        DESedeKeySpec spec = new DESedeKeySpec(key);        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");        deskey = keyfactory.generateSecret(spec);        Cipher cipher = Cipher.getInstance("desede" + "/ECB/PKCS5Padding");        Log.i("des", "decode init before");        cipher.init(Cipher.DECRYPT_MODE, deskey);        Log.i("des", "decode init after" + new String(data,"UTF-8"));        byte[] bOut = cipher.doFinal(data);        Log.i("des", "decode doFinal after");        return bOut;    }    /**     * CBC加密     * @param key 密钥     * @param keyiv IV     * @param data 明文     * @return Base64编码的密文     * @throws Exception     */    public static byte[] des3EncodeCBC( byte[] data)            throws Exception {        Key deskey = null;        DESedeKeySpec spec = new DESedeKeySpec(key);        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");        deskey = keyfactory.generateSecret(spec);        Cipher cipher = Cipher.getInstance("desede" + "/CBC/PKCS5Padding");        IvParameterSpec ips = new IvParameterSpec(keyiv);        cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);        byte[] bOut = cipher.doFinal(data);        return bOut;    }    /**     * CBC解密     * @param key 密钥     * @param keyiv IV     * @param data Base64编码的密文     * @return 明文     * @throws Exception     */    public static byte[] des3DecodeCBC(byte[] data)            throws Exception {        Key deskey = null;        DESedeKeySpec spec = new DESedeKeySpec(key);        SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("desede");        deskey = keyfactory.generateSecret(spec);        Cipher cipher = Cipher.getInstance("desede" + "/CBC/PKCS5Padding");        IvParameterSpec ips = new IvParameterSpec(keyiv);        cipher.init(Cipher.DECRYPT_MODE, deskey, ips);        byte[] bOut = cipher.doFinal(data);        return bOut;    }}

调用：
加密：byte[] temp = CryptoTools.des3EncodeECB(str.getBytes(“UTF-8”));
message = new String(Base64.encode(temp, Base64.DEFAULT),”UTF-8”);
解密：byte[] tmpt;
tmpt = Base64.decode(str.getBytes(“UTF-8”), Base64.DEFAULT);
tmpt = CryptoTools.ees3DecodeECB(tmpt);
str = new String(tmpt,”UTF-8”);

原文地址: 解决IllegalBlockSizeException:last block incomplete in decryption异常

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