RSA和AES加密解密

1.RSA加密

会生成一个公钥和一个私钥，一般都是用公钥加密，私钥解密

该工具类提供公钥加密解密，私钥加密解密

import org.apache.commons.codec.binary.Base64;

import javax.crypto.Cipher;
import java.security.*;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

/**
 * RSA加解密工具类，实现公钥加密私钥解密和私钥解密公钥解密
 */
public class RSAUtil {

    private static final String src = "abcdefghijklmnopqrstuvwxyz";

    public static void main(String[] args) throws Exception {
        System.out.println("\n");
        RSAKeyPair keyPair = generateKeyPair();
        System.out.println("公钥：" + keyPair.getPublicKey());
        System.out.println("私钥：" + keyPair.getPrivateKey());
        System.out.println("\n");
        test1(keyPair, src);
        System.out.println("\n");
        test2(keyPair, src);
        System.out.println("\n");
    }

    /**
     * 公钥加密私钥解密
     */
    private static void test1(RSAKeyPair keyPair, String source) throws Exception {
        System.out.println("***************** 公钥加密私钥解密开始 *****************");
        String text1 = encryptByPublicKey(keyPair.getPublicKey(), source);
        String text2 = decryptByPrivateKey(keyPair.getPrivateKey(), text1);
        System.out.println("加密前：" + source);
        System.out.println("加密后：" + text1);
        System.out.println("解密后：" + text2);
        if (source.equals(text2)) {
            System.out.println("解密字符串和原始字符串一致，解密成功");
        } else {
            System.out.println("解密字符串和原始字符串不一致，解密失败");
        }
        System.out.println("***************** 公钥加密私钥解密结束 *****************");
    }

    /**
     * 私钥加密公钥解密
     *
     * @throws Exception
     */
    private static void test2(RSAKeyPair keyPair, String source) throws Exception {
        System.out.println("***************** 私钥加密公钥解密开始 *****************");
        String text1 = encryptByPrivateKey(keyPair.getPrivateKey(), source);
        String text2 = decryptByPublicKey(keyPair.getPublicKey(), text1);
        System.out.println("加密前：" + source);
        System.out.println("加密后：" + text1);
        System.out.println("解密后：" + text2);
        if (source.equals(text2)) {
            System.out.println("解密字符串和原始字符串一致，解密成功");
        } else {
            System.out.println("解密字符串和原始字符串不一致，解密失败");
        }
        System.out.println("***************** 私钥加密公钥解密结束 *****************");
    }

    /**
     * 公钥解密
     *
     * @param publicKeyText
     * @param text
     * @return
     * @throws Exception
     */
    public static String decryptByPublicKey(String publicKeyText, String text) throws Exception {
        X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyText));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(Base64.decodeBase64(text));
        return new String(result);
    }

    /**
     * 私钥加密
     *
     * @param privateKeyText
     * @param text
     * @return
     * @throws Exception
     */
    public static String encryptByPrivateKey(String privateKeyText, String text) throws Exception {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyText));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encodeBase64String(result);
    }

    /**
     * 私钥解密
     *
     * @param privateKeyText
     * @param text
     * @return
     * @throws Exception
     */
    public static String decryptByPrivateKey(String privateKeyText, String text) throws Exception {
        PKCS8EncodedKeySpec pkcs8EncodedKeySpec5 = new PKCS8EncodedKeySpec(Base64.decodeBase64(privateKeyText));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec5);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.DECRYPT_MODE, privateKey);
        byte[] result = cipher.doFinal(Base64.decodeBase64(text));
        return new String(result);
    }

    /**
     * 公钥加密
     *
     * @param publicKeyText
     * @param text
     * @return
     */
    public static String encryptByPublicKey(String publicKeyText, String text) throws Exception {
        X509EncodedKeySpec x509EncodedKeySpec2 = new X509EncodedKeySpec(Base64.decodeBase64(publicKeyText));
        KeyFactory keyFactory = KeyFactory.getInstance("RSA");
        PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec2);
        Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        byte[] result = cipher.doFinal(text.getBytes());
        return Base64.encodeBase64String(result);
    }

    /**
     * 构建RSA密钥对
     *
     * @return
     * @throws NoSuchAlgorithmException
     */
    public static RSAKeyPair generateKeyPair() throws NoSuchAlgorithmException {
        KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
        keyPairGenerator.initialize(1024);
        KeyPair keyPair = keyPairGenerator.generateKeyPair();
        RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
        RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();
        String publicKeyString = Base64.encodeBase64String(rsaPublicKey.getEncoded());
        String privateKeyString = Base64.encodeBase64String(rsaPrivateKey.getEncoded());
        RSAKeyPair rsaKeyPair = new RSAKeyPair(publicKeyString, privateKeyString);
        return rsaKeyPair;
    }


    /**
     * RSA密钥对对象
     */
    public static class RSAKeyPair {

        private String publicKey;
        private String privateKey;

        public RSAKeyPair(String publicKey, String privateKey) {
            this.publicKey = publicKey;
            this.privateKey = privateKey;
        }

        public String getPublicKey() {
            return publicKey;
        }

        public String getPrivateKey() {
            return privateKey;
        }

    }

}

1.AES工具类

会生成密匙，原文加密，可以根据密匙进行解密

import java.util.UUID;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

/**
 * AES工具类，密钥必须是16位字符串
 */
public class AESUtils {

    /**偏移量,必须是16位字符串*/
    private static final String IV_STRING = "16-Bytes--String";

    /**
     * 默认的密钥
     */
    public static final String DEFAULT_KEY = "1bd83b249a414036";


    /**
     * 产生随机密钥(这里产生密钥必须是16位)
     */
    public static String generateKey() {
        String key = UUID.randomUUID().toString();
        key = key.replace("-", "").substring(0, 16);// 替换掉-号
        return key;
    }

    public static String encryptData(String key, String content) {
        byte[] encryptedBytes = new byte[0];
        try {
            byte[] byteContent = content.getBytes("UTF-8");
            // 注意，为了能与 iOS 统一
            // 这里的 key 不可以使用 KeyGenerator、SecureRandom、SecretKey 生成
            byte[] enCodeFormat = key.getBytes();
            SecretKeySpec secretKeySpec = new SecretKeySpec(enCodeFormat, "AES");
            byte[] initParam = IV_STRING.getBytes();
            IvParameterSpec ivParameterSpec = new IvParameterSpec(initParam);
            // 指定加密的算法、工作模式和填充方式
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            cipher.init(Cipher.ENCRYPT_MODE, secretKeySpec, ivParameterSpec);
            encryptedBytes = cipher.doFinal(byteContent);
            // 同样对加密后数据进行 base64 编码
            return Base64Utils.encode(encryptedBytes);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    public static String decryptData(String key, String content) {
        try {
            // base64 解码
            byte[] encryptedBytes = Base64Utils.decode(content);
            byte[] enCodeFormat = key.getBytes();
            SecretKeySpec secretKey = new SecretKeySpec(enCodeFormat, "AES");
            byte[] initParam = IV_STRING.getBytes();
            IvParameterSpec ivParameterSpec = new IvParameterSpec(initParam);
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            cipher.init(Cipher.DECRYPT_MODE, secretKey, ivParameterSpec);
            byte[] result = cipher.doFinal(encryptedBytes);
            return new String(result, "UTF-8");
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    public static void main(String[] args) {
        //加密
        String key = generateKey();
        String str = encryptData(key, "eyond黄家驹");
        String _str = AESUtils.decryptData(key, str);
        System.out.println("生成key:"+key);
        System.out.println("aes加密后: " + str);
        System.out.println("aes解密后: " + _str);
    }

}

工具类Base64Utils (没用到)

import org.apache.commons.codec.binary.Base64;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;

/** */
/**
 * <p>
 * BASE64编码解码工具包
 * </p>
 * <p>
 * 依赖
 * 		<dependency>
 * 			<groupId>commons-codec</groupId>
 * 			<artifactId>commons-codec</artifactId>
 * 			<version>1.9</version>
 * 		</dependency>
 * </p>
 * 
 * @author jun
 * @date 2012-5-19
 * @version 1.0
 */
public class Base64Utils {

	/** */
	/**
	 * 文件读取缓冲区大小
	 */
	private static final int CACHE_SIZE = 1024;

	/** */
	/**
	 * <p>
	 * BASE64字符串解码为二进制数据
	 * </p>
	 * 
	 * @param base64
	 * @return
	 * @throws Exception
	 */
	public static byte[] decode(String base64) throws Exception {
		//解密
		return Base64.decodeBase64(base64.getBytes());
	}

	public static String decode(byte[] b) {
		//解密
		return new String(Base64.decodeBase64(b));
	}


	/** */
	/**
	 * <p>
	 * 二进制数据编码为BASE64字符串
	 * </p>
	 * 
	 * @param bytes
	 * @return
	 * @throws Exception
	 */
	public static String encode(byte[] bytes) throws Exception {
		//加密
		return new String(Base64.encodeBase64Chunked(bytes));
	}


	/** */
	/**
	 * <p>
	 * 将文件编码为BASE64字符串
	 * </p>
	 * <p>
	 * 大文件慎用，可能会导致内存溢出
	 * </p>
	 * 
	 * @param filePath
	 *            文件绝对路径
	 * @return
	 * @throws Exception
	 */
	public static String encodeFile(String filePath) throws Exception {
		byte[] bytes = fileToByte(filePath);
		return encode(bytes);
	}

	/** */
	/**
	 * <p>
	 * BASE64字符串转回文件
	 * </p>
	 * 
	 * @param filePath
	 *            文件绝对路径
	 * @param base64
	 *            编码字符串
	 * @throws Exception
	 */
	public static void decodeToFile(String filePath, String base64)
			throws Exception {
		byte[] bytes = decode(base64);
		byteArrayToFile(bytes, filePath);
	}


	/** */
	/**
	 * <p>
	 * 文件转换为二进制数组
	 * </p>
	 * 
	 * @param filePath
	 *            文件路径
	 * @return
	 * @throws Exception
	 */
	public static byte[] fileToByte(String filePath) throws Exception {
		byte[] data = new byte[0];
		File file = new File(filePath);
		if (file.exists()) {
			FileInputStream in = new FileInputStream(file);
			ByteArrayOutputStream out = new ByteArrayOutputStream(2048);
			byte[] cache = new byte[CACHE_SIZE];
			int nRead = 0;
			while ((nRead = in.read(cache)) != -1) {
				out.write(cache, 0, nRead);
				out.flush();
			}
			out.close();
			in.close();
			data = out.toByteArray();
		}
		return data;
	}

	/** */
	/**
	 * <p>
	 * 二进制数据写文件
	 * </p>
	 * 
	 * @param bytes
	 *            二进制数据
	 * @param filePath
	 *            文件生成目录
	 */
	public static void byteArrayToFile(byte[] bytes, String filePath)
			throws Exception {
		InputStream in = new ByteArrayInputStream(bytes);
		File destFile = new File(filePath);
		if (!destFile.getParentFile().exists()) {
			destFile.getParentFile().mkdirs();
		}
		destFile.createNewFile();
		OutputStream out = new FileOutputStream(destFile);
		byte[] cache = new byte[CACHE_SIZE];
		int nRead = 0;
		while ((nRead = in.read(cache)) != -1) {
			out.write(cache, 0, nRead);
			out.flush();
		}
		out.close();
		in.close();
	}

}