1. 程式人生 > 實用技巧 >Java中使用OpenSSL生成的RSA公私鑰進行資料加解密

Java中使用OpenSSL生成的RSA公私鑰進行資料加解密

參考自:https://www.cnblogs.com/yaowen/p/9226566.html

   :https://www.cnblogs.com/wjqhuaxia/p/13829680.html

1.使用openssl生成RSA私鑰及證書

  生成 RSA 私鑰和自簽名證書,命令如下:

openssl req -newkey rsa:2048 -nodes -keyout rsa_private.pem -x509 -days 365 -out cert.crt

  req是證書請求的子命令,-newkey rsa:2048 -keyout rsa_private.pem 表示生成私鑰(PKCS8格式),-nodes 表示私鑰不加密,若不帶引數將提示輸入密碼;
-x509表示輸出證書,-days365 為有效期,此後根據提示輸入證書擁有者資訊;

  至此,可用的金鑰對已經生成好了,私鑰使用rsa_private.pem,公鑰證書採用cert.crt。

說明:  

  如果生成的私鑰檔案是PKCS#1格式的,則在使用時需在java中進行相應處理。不能直接使用。

RSAPrivateKeyStructure asn1PrivKey = new RSAPrivateKeyStructure((ASN1Sequence) ASN1Sequence.fromByteArray(priKeyData));  
RSAPrivateKeySpec rsaPrivKeySpec = new RSAPrivateKeySpec(asn1PrivKey.getModulus(), asn1PrivKey.getPrivateExponent());  
KeyFactory keyFactory= KeyFactory.getInstance("RSA");  
PrivateKey priKey= keyFactory.generatePrivate(rsaPrivKeySpec);

  首先將PKCS#1的私鑰檔案讀取出來(注意去掉減號開頭的註釋內容),然後使用Base64解碼讀出的字串,便得到priKeyData,也就是第一行程式碼中的引數。最後一行得到了私鑰。接下來的用法就沒什麼區別了。

2.使用java程式碼進行加密解

2.1RSA加密解密類

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Base64;

import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;


public class RSAEncrypt {
    /**
     * 位元組資料轉字串專用集合
     */
    private static final char[] HEX_CHAR = { '0', '1', '2', '3', '4', '5', '6',
            '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

    /**
     * 隨機生成金鑰對
     */
    public static void genKeyPair(String filePath) {
        // KeyPairGenerator類用於生成公鑰和私鑰對,基於RSA演算法生成物件
        KeyPairGenerator keyPairGen = null;
        try {
            keyPairGen = KeyPairGenerator.getInstance("RSA");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        // 初始化金鑰對生成器,金鑰大小為96-1024位
        keyPairGen.initialize(1024,new SecureRandom());
        // 生成一個金鑰對,儲存在keyPair中
        KeyPair keyPair = keyPairGen.generateKeyPair();
        // 得到私鑰
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        // 得到公鑰
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();
        try {
            // 得到公鑰字串
            String publicKeyString = new String(Base64.getEncoder().encodeToString(publicKey.getEncoded()));
            // 得到私鑰字串
            String privateKeyString = new String(Base64.getEncoder().encodeToString(privateKey.getEncoded()));
            // 將金鑰對寫入到檔案
            FileWriter pubfw = new FileWriter(filePath + "/publicKey.keystore");
            FileWriter prifw = new FileWriter(filePath + "/privateKey.keystore");
            BufferedWriter pubbw = new BufferedWriter(pubfw);
            BufferedWriter pribw = new BufferedWriter(prifw);
            pubbw.write(publicKeyString);
            pribw.write(privateKeyString);
            pubbw.flush();
            pubbw.close();
            pubfw.close();
            pribw.flush();
            pribw.close();
            prifw.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 從檔案中輸入流中載入公鑰
     *
     * @param in
     *            公鑰輸入流
     * @throws Exception
     *             載入公鑰時產生的異常
     */
    public static String loadPublicKeyByFile(String path) throws Exception {
        try {
            BufferedReader br = new BufferedReader(new FileReader(path
                    + "/rsa_public.crt"));
            String readLine = null;
            StringBuilder sb = new StringBuilder();
            while ((readLine = br.readLine()) != null) {
                sb.append(readLine);
            }
            br.close();
            return sb.toString();
        } catch (IOException e) {
            throw new Exception("公鑰資料流讀取錯誤");
        } catch (NullPointerException e) {
            throw new Exception("公鑰輸入流為空");
        }
    }

    /**
     * 從字串中載入公鑰
     *
     * @param publicKeyStr
     *            公鑰資料字串
     * @throws Exception
     *             載入公鑰時產生的異常
     */
    public static RSAPublicKey loadPublicKeyByStr(String publicKeyStr)
            throws Exception {
        try {
            byte[] buffer = Base64.getDecoder().decode(publicKeyStr);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(buffer);
            return (RSAPublicKey) keyFactory.generatePublic(keySpec);
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("無此演算法");
        } catch (InvalidKeySpecException e) {
            throw new Exception("公鑰非法");
        } catch (NullPointerException e) {
            throw new Exception("公鑰資料為空");
        }
    }
    
    /**
     * 獲取證書公鑰
     * @param cerPath
     * @return
     * @throws Exception
     */
    public static String getPublicKey(String cerPath) throws Exception {
		CertificateFactory certificatefactory = CertificateFactory.getInstance("X.509");
		FileInputStream fis = new FileInputStream(cerPath);
		X509Certificate Cert = (X509Certificate) certificatefactory.generateCertificate(fis);
		PublicKey pk = Cert.getPublicKey();
		String publicKey = Base64.getEncoder().encodeToString(pk.getEncoded());
		return publicKey;
	}

    /**
     * 從檔案中載入私鑰
     *
     * @param keyFileName
     *            私鑰檔名
     * @return 是否成功
     * @throws Exception
     */
    public static String loadPrivateKeyByFile(String path) throws Exception {
        try {
            BufferedReader br = new BufferedReader(new FileReader(path
                    + "/rsa_private.pem"));
            String readLine = null;
            StringBuilder sb = new StringBuilder();
            while ((readLine = br.readLine()) != null) {
                sb.append(readLine);
            }
            br.close();
            return sb.toString();
        } catch (IOException e) {
            throw new Exception("私鑰資料讀取錯誤");
        } catch (NullPointerException e) {
            throw new Exception("私鑰輸入流為空");
        }
    }

    public static RSAPrivateKey loadPrivateKeyByStr(String privateKeyStr)
            throws Exception {
        try {
            byte[] buffer = Base64.getDecoder().decode(privateKeyStr);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(buffer);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("無此演算法");
        } catch (InvalidKeySpecException e) {
            throw new Exception("私鑰非法");
        } catch (NullPointerException e) {
            throw new Exception("私鑰資料為空");
        }
    }

    /**
     * 公鑰加密過程
     *
     * @param publicKey
     *            公鑰
     * @param plainTextData
     *            明文資料
     * @return
     * @throws Exception
     *             加密過程中的異常資訊
     */
    public static byte[] encrypt(RSAPublicKey publicKey, byte[] plainTextData)
            throws Exception {
        if (publicKey == null) {
            throw new Exception("加密公鑰為空, 請設定");
        }
        Cipher cipher = null;
        try {
            // 使用預設RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.ENCRYPT_MODE, publicKey);
            byte[] output = cipher.doFinal(plainTextData);
            return output;
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("無此加密演算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("加密公鑰非法,請檢查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("明文長度非法");
        } catch (BadPaddingException e) {
            throw new Exception("明文資料已損壞");
        }
    }

    /**
     * 私鑰加密過程
     *
     * @param privateKey
     *            私鑰
     * @param plainTextData
     *            明文資料
     * @return
     * @throws Exception
     *             加密過程中的異常資訊
     */
    public static byte[] encrypt(RSAPrivateKey privateKey, byte[] plainTextData)
            throws Exception {
        if (privateKey == null) {
            throw new Exception("加密私鑰為空, 請設定");
        }
        Cipher cipher = null;
        try {
            // 使用預設RSA
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, privateKey);
            byte[] output = cipher.doFinal(plainTextData);
            return output;
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("無此加密演算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("加密私鑰非法,請檢查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("明文長度非法");
        } catch (BadPaddingException e) {
            throw new Exception("明文資料已損壞");
        }
    }

    /**
     * 私鑰解密過程
     *
     * @param privateKey
     *            私鑰
     * @param cipherData
     *            密文資料
     * @return 明文
     * @throws Exception
     *             解密過程中的異常資訊
     */
    public static byte[] decrypt(RSAPrivateKey privateKey, byte[] cipherData)
            throws Exception {
        if (privateKey == null) {
            throw new Exception("解密私鑰為空, 請設定");
        }
        Cipher cipher = null;
        try {
            // 使用預設RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.DECRYPT_MODE, privateKey);
            byte[] output = cipher.doFinal(cipherData);
            return output;
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("無此解密演算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("解密私鑰非法,請檢查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("密文長度非法");
        } catch (BadPaddingException e) {
            throw new Exception("密文資料已損壞");
        }
    }

    /**
     * 公鑰解密過程
     *
     * @param publicKey
     *            公鑰
     * @param cipherData
     *            密文資料
     * @return 明文
     * @throws Exception
     *             解密過程中的異常資訊
     */
    public static byte[] decrypt(RSAPublicKey publicKey, byte[] cipherData)
            throws Exception {
        if (publicKey == null) {
            throw new Exception("解密公鑰為空, 請設定");
        }
        Cipher cipher = null;
        try {
            // 使用預設RSA
            cipher = Cipher.getInstance("RSA");
            // cipher= Cipher.getInstance("RSA", new BouncyCastleProvider());
            cipher.init(Cipher.DECRYPT_MODE, publicKey);
            byte[] output = cipher.doFinal(cipherData);
            return output;
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("無此解密演算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("解密公鑰非法,請檢查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("密文長度非法");
        } catch (BadPaddingException e) {
            throw new Exception("密文資料已損壞");
        }
    }

    /**
     * 位元組資料轉十六進位制字串
     *
     * @param data
     *            輸入資料
     * @return 十六進位制內容
     */
    public static String byteArrayToString(byte[] data) {
        StringBuilder stringBuilder = new StringBuilder();
        for (int i = 0; i < data.length; i++) {
            // 取出位元組的高四位 作為索引得到相應的十六進位制識別符號 注意無符號右移
            stringBuilder.append(HEX_CHAR[(data[i] & 0xf0) >>> 4]);
            // 取出位元組的低四位 作為索引得到相應的十六進位制識別符號
            stringBuilder.append(HEX_CHAR[(data[i] & 0x0f)]);
            if (i < data.length - 1) {
                stringBuilder.append(' ');
            }
        }
        return stringBuilder.toString();
    }
}

2.2簽名及校驗類

package cn.com.wjqhuaxia;

import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.Base64;


/**
 * RSA簽名驗籤類
 */
public class RSASignature {

    /**
     * 簽名演算法
     */
    public static final String SIGN_ALGORITHMS = "SHA1WithRSA";

    /**
     * RSA簽名
     *
     * @param content
     *            待簽名資料
     * @param privateKey
     *            商戶私鑰
     * @param encode
     *            字符集編碼
     * @return 簽名值
     */
    public static String sign(String content, String privateKey, String encode) {
        try {
            PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.getDecoder().decode(privateKey));

            KeyFactory keyf = KeyFactory.getInstance("RSA");
            PrivateKey priKey = keyf.generatePrivate(priPKCS8);

            java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);

            signature.initSign(priKey);
            signature.update(content.getBytes(encode));

            byte[] signed = signature.sign();

            return new String(Base64.getEncoder().encodeToString(signed));
        } catch (Exception e) {
            e.printStackTrace();
        }

        return null;
    }

    public static String sign(String content, String privateKey) {
        try {
            PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.getDecoder().decode(privateKey));
            KeyFactory keyf = KeyFactory.getInstance("RSA");
            PrivateKey priKey = keyf.generatePrivate(priPKCS8);
            java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);
            signature.initSign(priKey);
            signature.update(content.getBytes());
            byte[] signed = signature.sign();
            return new String(Base64.getEncoder().encode(signed));
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * RSA驗簽名檢查
     *
     * @param content
     *            待簽名資料
     * @param sign
     *            簽名值
     * @param publicKey
     *            分配給開發商公鑰
     * @param encode
     *            字符集編碼
     * @return 布林值
     */
    public static boolean doCheck(String content, String sign, String publicKey, String encode) {
        try {
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            byte[] encodedKey = Base64.getDecoder().decode(publicKey);
            PublicKey pubKey = keyFactory.generatePublic(new X509EncodedKeySpec(encodedKey));

            java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);

            signature.initVerify(pubKey);
            signature.update(content.getBytes(encode));

            boolean bverify = signature.verify(Base64.getDecoder().decode(sign));
            return bverify;

        } catch (Exception e) {
            e.printStackTrace();
        }

        return false;
    }

    public static boolean doCheck(String content, String sign, String publicKey) {
        try {
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            byte[] encodedKey = Base64.getDecoder().decode(publicKey);
            PublicKey pubKey = keyFactory.generatePublic(new X509EncodedKeySpec(encodedKey));

            java.security.Signature signature = java.security.Signature.getInstance(SIGN_ALGORITHMS);

            signature.initVerify(pubKey);
            signature.update(content.getBytes());

            boolean bverify = signature.verify(Base64.getDecoder().decode(sign));
            return bverify;

        } catch (Exception e) {
            e.printStackTrace();
        }

        return false;
    }

}

2.3 測試類

package cn.com.wjqhuaxia;

import java.util.Base64;

public class MainTest {

	public static final String PRIVATE_KEY_FILE = "D:/tools/openssl/RSA/rsa_private.pem";
	//公鑰檔案路徑
//	public static final String PUBLIC_KEY_FILE = RSAUtil.class.getClassLoader().getResource("").getPath() + "rsa_private.key";
	public static final String PUBLIC_KEY_FILE = "D:/tools/openssl/RSA/rsa_public.crt";
	
	
    public static void main(String[] args) throws Exception {

        // RSAEncrypt.genKeyPair(filepath);
    	String filepath = "D:/tools/openssl/RSA/";


        System.out.println("--------------公鑰加密私鑰解密過程-------------------");
        // 公鑰
        String publicKeyString = RSAEncrypt.getPublicKey(PUBLIC_KEY_FILE);
        // 私鑰
//        String loadPrivateKeyByFile = RSAEncrypt.loadPrivateKeyByFile(filepath); //獲取私鑰
        String privateKeyString = "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";
        
        String plainText = "ihep_公鑰加密私鑰解密";
        System.out.println("原文:" + plainText);
        
        // 公鑰加密過程
        byte[] cipherData = RSAEncrypt.encrypt(RSAEncrypt.loadPublicKeyByStr(publicKeyString),
                plainText.getBytes());
        String cipher = new String(Base64.getEncoder().encode(cipherData));
        System.out.println("加密:" + cipher);
        // 私鑰解密過程
        byte[] res = RSAEncrypt.decrypt(RSAEncrypt.loadPrivateKeyByStr(privateKeyString),
        		Base64.getDecoder().decode(cipher));
        String restr = new String(res);
        System.out.println("解密:" + restr);
        System.out.println();

        System.out.println("--------------私鑰加密公鑰解密過程-------------------");
        plainText = "ihep_私鑰加密公鑰解密";
        // 私鑰加密過程
        cipherData = RSAEncrypt.encrypt(RSAEncrypt.loadPrivateKeyByStr(privateKeyString),
                plainText.getBytes());
        cipher = new String(Base64.getEncoder().encode(cipherData));
        // 公鑰解密過程
        res = RSAEncrypt.decrypt(RSAEncrypt.loadPublicKeyByStr(publicKeyString),
        		Base64.getDecoder().decode(cipher));
        restr = new String(res);
        System.out.println("原文:" + plainText);
        System.out.println("加密:" + cipher);
        System.out.println("解密:" + restr);
        System.out.println();

        System.out.println("---------------私鑰簽名過程------------------");
        String content = "ihep_這是用於簽名的原始資料";
        String signstr = RSASignature.sign(content, privateKeyString);
        System.out.println("簽名原串:" + content);
        System.out.println("簽名串:" + signstr);
        System.out.println();

        System.out.println("---------------公鑰校驗簽名------------------");
        System.out.println("簽名原串:" + content);
        System.out.println("簽名串:" + signstr);

        System.out.println("驗簽結果:" + RSASignature.doCheck(content, signstr, publicKeyString));
        System.out.println();

    }
}