java运用SM4国密算法对文件的加密与解密的实现

  <dependency>            <groupId>com.hutool</groupId>            <artifactId>all</artifactId>            <version>4.6.17</version>            <scope>system</scope>            <systemPath>${project.basedir}/src/main/webapp/lib/sm4/hutool-all-4.6.17.jar</systemPath>        </dependency>        <dependency>            <groupId>com.bcprov</groupId>            <artifactId>jdk15on</artifactId>            <version>1.59</version>            <scope>system</scope>            <systemPath>${project.basedir}/src/main/webapp/lib/sm4/bcprov-jdk15on-1.59.jar</systemPath>        </dependency>

首先我们在idae开发工具导入导入pom.xml的两个必要依赖

jar包下载地址：百度网盘请输入提取码 npn8

图上systemPath为jar包的文件路径，我们需要使用以下的路径存储jar包。（也可以自己设置）

java包的文件路径如图所示

然后创建所需要加密的文件，需要加密的文件内容，并保存文件加密的地址。

以下是代码实现:

使用密钥"0123456789abcdeffedcba9876543210"对文件加解密

import java.io.ByteArrayInputStream;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStream;import java.security.InvalidKeyException;import java.security.Key;import java.security.NoSuchAlgorithmException;import java.security.NoSuchProviderException;import java.security.Security;import javax.crypto.Cipher;import javax.crypto.CipherOutputStream;import javax.crypto.NoSuchPaddingException;import javax.crypto.spec.SecretKeySpec;import cn.hutool.core.io.FileUtil;import cn.hutool.core.io.IoUtil;import org.bouncycastle.jcajce.io.CipherInputStream;import org.bouncycastle.jce.provider.BouncyCastleProvider;import org.bouncycastle.pqc.math.linearalgebra.ByteUtils;public class SM4Tools {    public static void main(String[] args) throws Exception {        String sp = "D:\\sm4jiami\\tt\\tt.txt";//原始文件        String dp = "D:\\sm4jiami\\tt\\tt.txt加密文件";//加密后文件        String dp2 = "D:\\sm4jiami\\tt\\tt.txt解密文件";//解密后文件        // String key = "05d986b1141227cb20d46d0b56202024";        // byte[] keyData = ByteUtils.fromHexString(key);        //加密文件        encryptFile(sp,dp);        System.out.println("加密成功");        //解密文件        decryptFile(dp,dp2);        System.out.println("解密成功");    }    private static String key = "0123456789abcdeffedcba9876543210";  //使用到的密钥对文件加密    private static byte[] keyData = ByteUtils.fromHexString(key);    static{        if (Security.getProvider(BouncyCastleProvider.PROVIDER_NAME) == null){            //No such provider: BC            Security.addProvider(new BouncyCastleProvider());        }    }    //生成 Cipher    public static Cipher generateCipher(int mode,byte[] keyData) throws InvalidKeyException, NoSuchPaddingException, NoSuchAlgorithmException, NoSuchProviderException {        Cipher cipher = Cipher.getInstance("SM4/ECB/PKCS5Padding", BouncyCastleProvider.PROVIDER_NAME);        Key sm4Key = new SecretKeySpec(keyData, "SM4");        cipher.init(mode, sm4Key);        return cipher;    }    //加密文件    public static void encryptFile(String sourcePath,String targetPath){        //加密文件        try {            Cipher cipher = generateCipher(Cipher.ENCRYPT_MODE,keyData);            CipherInputStream cipherInputStream = new CipherInputStream(new FileInputStream(sourcePath), cipher);            FileUtil.writeFromStream(cipherInputStream, targetPath);            IoUtil.close(cipherInputStream);        } catch (InvalidKeyException e) {            e.printStackTrace();        } catch (NoSuchPaddingException e) {            e.printStackTrace();        } catch (NoSuchAlgorithmException e) {            e.printStackTrace();        } catch (NoSuchProviderException e) {            e.printStackTrace();        } catch (FileNotFoundException e) {            e.printStackTrace();        }    }    /**     * 解密文件     * @param sourcePath 待解密的文件路径     * @param targetPath 解密后的文件路径     */    public static void decryptFile(String sourcePath, String targetPath) {        FileInputStream in =null;        ByteArrayInputStream byteArrayInputStream =null;        OutputStream out = null;        CipherOutputStream cipherOutputStream=null;        try {            in = new FileInputStream(sourcePath);            byte[] bytes = IoUtil.readBytes(in);            byteArrayInputStream = IoUtil.toStream(bytes);            Cipher cipher = generateCipher(Cipher.DECRYPT_MODE,keyData);            out = new FileOutputStream(targetPath);            cipherOutputStream = new CipherOutputStream(out, cipher);            IoUtil.copy(byteArrayInputStream, cipherOutputStream);        } catch (IOException e) {            e.printStackTrace();        } catch (NoSuchPaddingException e) {            e.printStackTrace();        } catch (NoSuchAlgorithmException e) {            e.printStackTrace();        } catch (InvalidKeyException e) {            e.printStackTrace();        } catch (NoSuchProviderException e) {            e.printStackTrace();        }finally {            IoUtil.close(cipherOutputStream);            IoUtil.close(out);            IoUtil.close(byteArrayInputStream);            IoUtil.close(in);        }    }}

运行代码