Java中使用OpenSSL生成的RSA公私钥对数据进行加解密

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/weixin_43215250/article/details/85137731

使用OpenSSL来生成私钥和公钥

1. 验证机器上是否安装openssl

   命令：openssl version -a

   [root@node00 test]# openssl version -a
   OpenSSL 1.0.2k-fips  26 Jan 2017
   built on: reproducible build, date unspecified
   platform: linux-x86_64
   options:  bn(64,64) md2(int) rc4(16x,int) des(idx,cisc,16,int) idea(int) blowfish(idx) 
   compiler: gcc -I. -I.. -I../include  -fPIC -DOPENSSL_PIC -DZLIB -DOPENSSL_THREADS -D_REENTRANT -DDSO_DLFCN -DHAVE_DLFCN_H -DKRB5_MIT -m64 -DL_ENDIAN -Wall -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector-strong --param=ssp-buffer-size=4 -grecord-gcc-switches   -m64 -mtune=generic -Wa,--noexecstack -DPURIFY -DOPENSSL_IA32_SSE2 -DOPENSSL_BN_ASM_MONT -DOPENSSL_BN_ASM_MONT5 -DOPENSSL_BN_ASM_GF2m -DRC4_ASM -DSHA1_ASM -DSHA256_ASM -DSHA512_ASM -DMD5_ASM -DAES_ASM -DVPAES_ASM -DBSAES_ASM -DWHIRLPOOL_ASM -DGHASH_ASM -DECP_NISTZ256_ASM
   OPENSSLDIR: "/etc/pki/tls"
   engines:  rdrand dynamic 
   [root@node00 test]# 
   

2. 生成私钥

   openssl genrsa -out rsa_private_key.pem 2048

   openssl随机生成了一份私钥，加密长度是1024位。加密长度是指理论上最大允许”被加密的信息“长度的限制，也就是明文的长度限制。随着这个参数的增大（比方说2048），允许的明文长度也会增加，但同时也会造成计算复杂度的极速增长。一般推荐的长度就是1024位(128字节)。

   查看私钥文件：rsa_private_key.pem，内容都是标准的ASCII字符，开头一行和结尾一行有明显的标记，真正的私钥数据是中间的不规则字符。

   [root@node00 test]# cat rsa_private_key.pem 
   -----BEGIN RSA PRIVATE KEY-----
   MIICXwIBAAKBgQD3g6KX0M0pM5HdC39verZMxDmLyQZ4trDCpmn+DMB3yTf4aVPL
   dgBHhqiw9bnyOwltqlzSlZyr/8jcwimC2pOg9mP8PT8e5NcoqINkcFYwLAlwGDix
   TdKLF0+7HcwfIqJPpX+4WRdsBc2r6Tqr2OlrgKCLQsLbMplaRjPnsBqGDwIDAQAB
   AoGBANTCy64yp1jGYpkfPBEI69G7TzgwuiZj7De2MyBVt9CAIGOhro0TxxO01icf
   YxKs2uLw8c93GfDj87aIFITN/N1MiwVjF9hTxacYkQ2KKiks2kNv5UjHcfgQVpj3
   rfSADJ4NEeV52cp3VHVrF8n+cjvct6boMa7/f6StvfewUxL5AkEA/N8sKmbvTRgM
   DE+vEI06U0Hv5bsGyppbt964WhCwBhzvHX4SZypcmuu3AkQX60ep9Sz8/0JZcJXr
   ZEfEs402RQJBAPqTftznOuC7Uoyh+ogyxYJ1mmO4TnTdh5RqTVbC9DUvxtUtUgqP
   JJRaj+GSoZ+f0+99l1NaqoOtVkq226UmKkMCQQChW1sYV4SdohmWBYbFPgkYtXt6
   EUS9JZAfHQxv1DQuQmpGXHsrv3lGFeE6ne7RYHJQE3wA+fqOf+urmqwmkpYtAkEA
   x5FZZM600e/fWypWwsrNC45mnC1aLzGQnd/cING8de/LSFWEFezTkWRfW6TRHLTK
   st8v+q8nRyByrabdYLb4yQJBAIruwdUxt9meTuJgN/YkijCt6Jc8+sOAmSep0G5i
   gcAvSdn7hlRx/jj1FRA5MhSmGmeJdoDlAcWUBaHR/elOedU=
   -----END RSA PRIVATE KEY-----
   

3. 根据私钥生产公钥

   openssl rsa -in rsa_private_key.pem -out rsa_public_key.pem -pubout

   查看公钥：

   [root@node00 test]# cat rsa_public_key.pem 
   -----BEGIN PUBLIC KEY-----
   MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQD3g6KX0M0pM5HdC39verZMxDmL
   yQZ4trDCpmn+DMB3yTf4aVPLdgBHhqiw9bnyOwltqlzSlZyr/8jcwimC2pOg9mP8
   PT8e5NcoqINkcFYwLAlwGDixTdKLF0+7HcwfIqJPpX+4WRdsBc2r6Tqr2OlrgKCL
   QsLbMplaRjPnsBqGDwIDAQAB
   -----END PUBLIC KEY-----
   

4. PKCS#8编码

   指明输入私钥文件为rsa_private_key.pem，输出私钥文件为pkcs8_rsa_private_key.pem，不采用任何二次加密（-nocrypt）

   openssl pkcs8 -topk8 -in rsa_private_key.pem -out pkcs8_rsa_private_key.pem -nocrypt

   查看PKCS#8编码私钥：

   [root@node00 test]# cat pkcs8_rsa_private_key.pem 
   -----BEGIN PRIVATE KEY-----
   MIICeQIBADANBgkqhkiG9w0BAQEFAASCAmMwggJfAgEAAoGBAPeDopfQzSkzkd0L
   f296tkzEOYvJBni2sMKmaf4MwHfJN/hpU8t2AEeGqLD1ufI7CW2qXNKVnKv/yNzC
   KYLak6D2Y/w9Px7k1yiog2RwVjAsCXAYOLFN0osXT7sdzB8iok+lf7hZF2wFzavp
   OqvY6WuAoItCwtsymVpGM+ewGoYPAgMBAAECgYEA1MLLrjKnWMZimR88EQjr0btP
   ODC6JmPsN7YzIFW30IAgY6GujRPHE7TWJx9jEqza4vDxz3cZ8OPztogUhM383UyL
   BWMX2FPFpxiRDYoqKSzaQ2/lSMdx+BBWmPet9IAMng0R5XnZyndUdWsXyf5yO9y3
   pugxrv9/pK2997BTEvkCQQD83ywqZu9NGAwMT68QjTpTQe/luwbKmlu33rhaELAG
   HO8dfhJnKlya67cCRBfrR6n1LPz/QllwletkR8SzjTZFAkEA+pN+3Oc64LtSjKH6
   iDLFgnWaY7hOdN2HlGpNVsL0NS/G1S1SCo8klFqP4ZKhn5/T732XU1qqg61WSrbb
   pSYqQwJBAKFbWxhXhJ2iGZYFhsU+CRi1e3oRRL0lkB8dDG/UNC5CakZceyu/eUYV
   4Tqd7tFgclATfAD5+o5/66uarCaSli0CQQDHkVlkzrTR799bKlbCys0LjmacLVov
   MZCd39wg0bx178tIVYQV7NORZF9bpNEctMqy3y/6rydHIHKtpt1gtvjJAkEAiu7B
   1TG32Z5O4mA39iSKMK3olzz6w4CZJ6nQbmKBwC9J2fuGVHH+OPUVEDkyFKYaZ4l2
   gOUBxZQFodH96U551Q==
   -----END PRIVATE KEY-----
   

RSA加密解密工具类

package com.yimen.data.test;

import java.io.*;
import java.security.*;
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 javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import org.bouncycastle.util.encoders.Base64;
import sun.misc.BASE64Decoder;

/**
 * 生成私钥：openssl genrsa -out rsa_private_key.pem 1024
 * 根据私钥生成公钥：openssl rsa -in rsa_private_key.pem -out rsa_public_key.pem -pubout
 * 私钥还不能直接被使用，需要进行PKCS#8编码：openssl pkcs8 -topk8 -in rsa_private_key.pem -out pkcs8_rsa_private_key.pem -nocrypt
 * sha1签名 openssl sha1 -sign rsa_private_key.pem -out rsasign.bin tos.txt
 * pkcs8_rsa_private_key 私钥
 * java可以使用
 */
public class RSAEncrypt {

    /**
     * 字节数据转字符串专用集合
     */
    private static final char[] HEX_CHAR = {'0', '1', '2', '3', '4', '5', '6',
            '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};


    /**
     * 随机生成密钥对
     * 生成公私钥的位置
     */
    public void genKeyPair(String filePath) {
        // KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象
        KeyPairGenerator keyPairGen = null;
        try {
            keyPairGen = KeyPairGenerator.getInstance("RSA");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }
        // 初始化密钥对生成器，密钥大小为96-1024位
        keyPairGen.initialize(1024, new SecureRandom());
        // 生成一个密钥对，保存在keyPair中
        KeyPair keyPair = keyPairGen.generateKeyPair();
        // 得到私钥
        RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate();
        // 得到公钥
        RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic();

        try {
            // 得到公钥字符串
           //Base64 base64 = new Base64();
            BASE64Encoder base64 = new BASE64Encoder();
            String publicKeyString = new String(base64.encode(publicKey.getEncoded()));
            // 得到私钥字符串
            String privateKeyString = new String(base64.encode(privateKey.getEncoded()));
            // 将密钥对写入到文件
            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();
        }
    }

    /**
     * 从字符串中加载公钥
     *
     * @param publicKeyStr 公钥数据字符串
     * @throws Exception 加载公钥时产生的异常
     */
    public static RSAPublicKey loadPublicKeyByStr(String publicKeyStr) throws Exception {
        try {
            BASE64Decoder base64Decoder = new BASE64Decoder();
            byte[] buffer = base64Decoder.decodeBuffer(publicKeyStr);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            X509EncodedKeySpec keySpec = new X509EncodedKeySpec(buffer);
            return (RSAPublicKey) keyFactory.generatePublic(keySpec);
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("无此算法");
        } catch (InvalidKeySpecException e) {
            throw new Exception("公钥非法");
        } catch (IOException e) {
            throw new Exception("公钥数据内容读取错误");
        } catch (NullPointerException e) {
            throw new Exception("公钥数据为空");
        }
    }

    /**
     * 从文件中输入流中加载公钥
     *
     * @param path
     *            公钥路径
     * @param flag
     *            true 为hdfs文件系统路径
     * @throws Exception
     *             加载公钥时产生的异常
     */
    public static String loadPublicKeyByFile(String path, boolean flag) throws Exception {
        try {
        	 BufferedReader br = null;
            if(flag){
                Configuration conf = new Configuration();
                FileSystem fs = FileSystem.get(conf);
                FSDataInputStream in = fs.open(new Path(path));
                br = new BufferedReader(new InputStreamReader(in));
            }else{
                br = new BufferedReader(new FileReader(path));
            }
            String readLine = null;
            StringBuilder sb = new StringBuilder();
            while ((readLine = br.readLine()) != null) {
                if (!readLine.contains("PUBLIC KEY")){
                    sb.append(readLine);
                }
            }         
            br.close();
            return sb.toString();
        } catch (IOException e) {
            throw new Exception("公钥数据流读取错误");
        } catch (NullPointerException e) {
            throw new Exception("公钥输入流为空");
        }
    }

    /**
     * 从字符串中加载私钥
     *
     * @param privateKeyStr 私钥文件名
     * @return 是否成功
     * @throws Exception
     */
    public static RSAPrivateKey loadPrivateKeyByStr(String privateKeyStr) throws Exception {
        try {
            BASE64Decoder base64Decoder = new BASE64Decoder();
            byte[] buffer = base64Decoder.decodeBuffer(privateKeyStr);
            PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(buffer);
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            return (RSAPrivateKey) keyFactory.generatePrivate(keySpec);
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("无此算法");
        } catch (InvalidKeySpecException e) {
            throw new Exception("私钥非法");
        } catch (IOException e) {
            throw new Exception("私钥数据内容读取错误");
        } catch (NullPointerException e) {
            throw new Exception("私钥数据为空");
        }
    }

    /**
     * 从文件中加载私钥
     *
     * @param path
     *            私钥文件名
     * @param flag
     *            true 为hdfs文件系统路径
     * @return 是否成功
     * @throws Exception
     */
    public static String loadPrivateKeyByFile(String path, boolean flag) throws Exception {
        try {
            BufferedReader br = null;
            if(flag){
                Configuration conf = new Configuration();
                FileSystem fs = FileSystem.get(conf);
                FSDataInputStream in = fs.open(new Path(path));
                br = new BufferedReader(new InputStreamReader(in));
            }else{
                br = new BufferedReader(new FileReader(path));
            }
            String readLine = null;
            StringBuilder sb = new StringBuilder();
            while ((readLine = br.readLine()) != null) {
                if (!readLine.contains("PRIVATE KEY")){
                    sb.append(readLine);
                }
            }
            br.close();
            return sb.toString();
        } catch (IOException e) {
            throw new Exception("私钥数据读取错误");
        } catch (NullPointerException e) {
            throw new Exception("私钥输入流为空");
        }
    }


    /**
     * 公钥加密
     *
     * @param publicKey     公钥
     * @param plainTextData 明文数据
     * @return
     * @throws Exception 加密过程中的异常信息
     */
    public static byte[] encrypt(RSAPublicKey publicKey, byte[] plainTextData)
            throws Exception {
        if (publicKey == null) {
            throw new Exception("加密公钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认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("无此加密算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("加密公钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("明文长度非法");
        } catch (BadPaddingException e) {
            throw new Exception("明文数据已损坏");
        }
    }

    /**
     * 公钥解密
     *
     * @param publicKey  公钥
     * @param cipherData 密文数据
     * @return 明文
     * @throws Exception 解密过程中的异常信息
     */
    public static byte[] decrypt(RSAPublicKey publicKey, byte[] cipherData)
            throws Exception {
        if (publicKey == null) {
            throw new Exception("解密公钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认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("无此解密算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("解密公钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("密文长度非法");
        } catch (BadPaddingException e) {
            throw new Exception("密文数据已损坏");
        }
    }

    /**
     * 私钥加密
     *
     * @param privateKey    私钥
     * @param plainTextData 明文数据
     * @return
     * @throws Exception 加密过程中的异常信息
     */
    public static byte[] encrypt(RSAPrivateKey privateKey, byte[] plainTextData)
            throws Exception {
        if (privateKey == null) {
            throw new Exception("加密私钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认RSA
            cipher = Cipher.getInstance("RSA");
            cipher.init(Cipher.ENCRYPT_MODE, privateKey);
            byte[] output = cipher.doFinal(plainTextData);
            return output;
        } catch (NoSuchAlgorithmException e) {
            throw new Exception("无此加密算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("加密私钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("明文长度非法");
        } catch (BadPaddingException e) {
            throw new Exception("明文数据已损坏");
        }
    }

    /**
     * 私钥解密
     *
     * @param privateKey 私钥
     * @param cipherData 密文数据
     * @return 明文
     * @throws Exception 解密过程中的异常信息
     */
    public static byte[] decrypt(RSAPrivateKey privateKey, byte[] cipherData) throws Exception {
        if (privateKey == null) {
            throw new Exception("解密私钥为空, 请设置");
        }
        Cipher cipher = null;
        try {
            // 使用默认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("无此解密算法");
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
            return null;
        } catch (InvalidKeyException e) {
            throw new Exception("解密私钥非法,请检查");
        } catch (IllegalBlockSizeException e) {
            throw new Exception("密文长度非法");
        } catch (BadPaddingException e) {
            throw new Exception("密文数据已损坏");
        }
    }


    /**
     * 字节数据转十六进制字符串
     *
     * @param data 输入数据
     * @return 十六进制内容
     */
    public static String byteArrayToString(byte[] data) {
        StringBuilder stringBuilder = new StringBuilder();
        for (int i = 0; i < data.length; i++) {
            // 取出字节的高四位 作为索引得到相应的十六进制标识符 注意无符号右移
            stringBuilder.append(HEX_CHAR[(data[i] & 0xf0) >>> 4]);
            // 取出字节的低四位 作为索引得到相应的十六进制标识符
            stringBuilder.append(HEX_CHAR[(data[i] & 0x0f)]);
            if (i < data.length - 1) {
                stringBuilder.append(' ');
            }
        }
        return stringBuilder.toString();
    }

    // btye转换hex函数
    public static String ByteToHex(byte[] byteArray) {
        StringBuffer StrBuff = new StringBuffer();
        for (int i = 0; i < byteArray.length; i++) {
            if (Integer.toHexString(0xFF & byteArray[i]).length() == 1) {
                StrBuff.append("0").append(
                        Integer.toHexString(0xFF & byteArray[i]));
            } else {
                StrBuff.append(Integer.toHexString(0xFF & byteArray[i]));
            }
        }
        return StrBuff.toString();
    }


    /**
     * 以字节为单位读取文件，常用于读二进制文件，如图片、声音、影像等文件。
     */
    public static byte[] readFileByBytes(String fileName) {
        File file = new File(fileName);
        InputStream in = null;
        byte[] txt = new byte[(int) file.length()];
        try {
            // 一次读一个字节
            in = new FileInputStream(file);
            int tempbyte;
            int i = 0;

            while ((tempbyte = in.read()) != -1) {
                txt[i] = (byte) tempbyte;
                i++;
            }
            in.close();
            return txt;
        } catch (IOException e) {
            e.printStackTrace();
            return txt;
        }
    }
}

如果私钥文件编码是PKCS#1格式，这种格式Java是支持的，增加如下代码：

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);

签名及校验类

package com.yimen.data.test;

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

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

/**
 * RSA签名验签类
 */
public class RSASignature {

    /**
     * 签名算法
     */
    public static final String SIGN_ALGORITHMS = "SHA1WithRSA";

    /**
     * RSA签名
     *
     * @param content    待签名数据
     * @param privateKey 商户私钥
     * @param encode     字符集编码
     * @return 签名值
     */
    public static String sign(String content, String privateKey, String encode) {
        try {
            Base64 base64 = new Base64();
            PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(base64.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.encode(signed));
        } catch (Exception e) {
            e.printStackTrace();
        }

        return null;
    }

    public static String sign(String content, String privateKey) {
        try {
            Base64 base64 = new Base64();
            PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(base64.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.encode(signed));
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * RSA验签名检查
     *
     * @param content   待签名数据
     * @param sign      签名值
     * @param publicKey 分配给开发商公钥
     * @param encode    字符集编码
     * @return 布尔值
     */
    public static boolean doCheck(String content, String sign, String publicKey, String encode) {
        try {
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            Base64 base64 = new Base64();
            byte[] encodedKey = base64.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.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");
            Base64 base64 = new Base64();
            byte[] encodedKey = base64.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.decode(sign));
            return bverify;

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

}

测试类

package com.yimen.data.test;

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

public class MainTest {

    public static void main(String[] args) throws Exception {
        String filepath = "D://tmp//";

//         RSAEncrypt.genKeyPair(filepath);
        //公钥
        String publicKeyStr = RSAEncrypt.loadPublicKeyByFile(filepath + "publicKey.keystore");
        // 私钥
        String privateKeyStr = RSAEncrypt.loadPrivateKeyByFile(filepath + "privateKey.keystore");

        Base64 base64 = new Base64();
        System.out.println("--------------公钥加密私钥解密过程-------------------");
        String plainText = "ihep_公钥加密私钥解密";
        // 公钥加密过程

        System.out.println(publicKeyStr);
        byte[] cipherData = RSAEncrypt.encrypt(RSAEncrypt.loadPublicKeyByStr(publicKeyStr), plainText.getBytes());
        String cipher = new String(base64.encode(cipherData));
        // 私钥解密过程

        System.out.println(privateKeyStr);
        byte[] res = RSAEncrypt.decrypt(RSAEncrypt.loadPrivateKeyByStr(privateKeyStr),
                base64.decode(cipher));
        String 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("--------------私钥加密公钥解密过程-------------------");

        plainText = "ihep_私钥加密公钥解密";
        // 私钥加密过程
        cipherData = RSAEncrypt.encrypt(RSAEncrypt.loadPrivateKeyByStr(privateKeyStr), plainText.getBytes());
        cipher = new String(base64.encode(cipherData));
        // 公钥解密过程
        res = RSAEncrypt.decrypt(RSAEncrypt.loadPublicKeyByStr(publicKeyStr), base64.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("---------------私钥签名过程------------------");
        String content = "ihep_这是用于签名的原始数据";
        String signstr = RSASignature.sign(content, privateKeyStr);
        System.out.println("签名原串：" + content);
        System.out.println("签名串：" + signstr);
        System.out.println();

        System.out.println("---------------公钥校验签名------------------");
        System.out.println("签名原串：" + content);
        System.out.println("签名串：" + signstr);

        System.out.println("验签结果：" + RSASignature.doCheck(content, signstr, publicKeyStr));
        System.out.println();

    }
}