java基础---->数字签名算法的介绍

　　数字签名（又称公钥数字签名）是一种类似写在纸上的普通的物理签名，但是使用了公钥加密领域的技术实现，用于鉴别数字信息的方法。关于数字签名的介绍，可以参见百度百科：http://baike.baidu.com/view/7626.htm。今天，我们就开始学习java中数字签名的使用。

项目结构如下：

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" alt="" />

DSA算法

一、 HuhxDSA.java

package com.huhx.security;

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.interfaces.DSAPrivateKey;
import java.security.interfaces.DSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

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

/**
 * writer: huhx
 */
public class HuhxDSA {
    private final static String src = "http://www.cnblogs.com/huhx";

    public static void main(String[] args) {
        // 初始化签名
        try {
            KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("DSA");
            keyPairGenerator.initialize(512);
            KeyPair keyPair = keyPairGenerator.generateKeyPair();
            DSAPublicKey dsaPublicKey = (DSAPublicKey) keyPair.getPublic();
            DSAPrivateKey dsaPrivateKey = (DSAPrivateKey) keyPair.getPrivate();

            // 执行签名
            PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(dsaPrivateKey.getEncoded());
            KeyFactory keyFactory = KeyFactory.getInstance("DSA");
            PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
            Signature signature = Signature.getInstance("SHA1withDSA");
            signature.initSign(privateKey);
            signature.update(src.getBytes());
            byte[] result = signature.sign();
            System.out.println("jdk dsa sign: " + Hex.encodeHexString(result));

            // 验证签名
            X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(dsaPublicKey.getEncoded());
            keyFactory = KeyFactory.getInstance("DSA");
            PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
            signature = Signature.getInstance("SHA1withDSA");
            signature.initVerify(publicKey);
            signature.update(src.getBytes());
            boolean bool = signature.verify(result);
            System.out.println("jdk dsa: " + bool);

        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

二、 运行结果如下：

jdk dsa sign: 302d0215009461ae45922c11159d3b6dc4c70eb0748763d23202146f5f9a5eedb36a760cf8b9b1d1d1fdc10636aafe
jdk dsa: true

RSA算法

一、 HuhxRSA.java

package com.huhx.security;

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

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

/**
 * writer: huhx
 */
public class HuhxRSA {
    private final static String src = "http://www.cnblogs.com/huhx";

    public static void main(String[] args) {
        try {
            // 初始化签名
            KeyPairGenerator generator = KeyPairGenerator.getInstance("RSA");
            generator.initialize(512);
            KeyPair keyPair = generator.generateKeyPair();
            RSAPublicKey rsaPublicKey = (RSAPublicKey) keyPair.getPublic();
            RSAPrivateKey rsaPrivateKey = (RSAPrivateKey) keyPair.getPrivate();

            // 执行签名
            PKCS8EncodedKeySpec encodedKeySpec = new PKCS8EncodedKeySpec(rsaPrivateKey.getEncoded());
            KeyFactory keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(encodedKeySpec);
            Signature signature = Signature.getInstance("MD5withRSA");
            signature.initSign(privateKey);
            signature.update(src.getBytes());
            byte[] result = signature.sign();
            System.out.println("jdk rsa sign: " + Hex.encodeHexString(result));

            // 验证签名
            X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(rsaPublicKey.getEncoded());
            keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
            signature = Signature.getInstance("MD5withRSA");
            signature.initVerify(publicKey);
            signature.update(src.getBytes());
            boolean bool = signature.verify(result);
            System.out.println("jdk rsa: " + bool);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

二、 运行结果如下：

jdk rsa sign: 564dc7f96c85a7a42e579ae191997c892f234272d220e3f062cf52071e827164fadd52720b69704979fc11810bdbf92b01dd3f5f26a621ffe699ef601d08fb6c
jdk rsa: true

ECDSA算法

一、 HuhxECDSA.java

package com.huhx.security;

import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.interfaces.ECPrivateKey;
import java.security.interfaces.ECPublicKey;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

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

/**
 * writer: huhx
 */
public class HuhxECDSA {
    private final static String src = "mhttp://www.cnblogs.com/huhx";

    public static void main(String[] args) {
        try {
            // 初始化签名
            KeyPairGenerator generator = KeyPairGenerator.getInstance("EC");
            generator.initialize(256);
            KeyPair keyPair = generator.generateKeyPair();
            ECPublicKey ecPublicKey = (ECPublicKey) keyPair.getPublic();
            ECPrivateKey ecPrivateKey = (ECPrivateKey) keyPair.getPrivate();

            // 执行签名
            PKCS8EncodedKeySpec encodedKeySpec = new PKCS8EncodedKeySpec(ecPrivateKey.getEncoded());
            KeyFactory keyFactory = KeyFactory.getInstance("EC");
            PrivateKey privateKey = keyFactory.generatePrivate(encodedKeySpec);
            Signature signature = Signature.getInstance("SHA1withECDSA");
            signature.initSign(privateKey);
            signature.update(src.getBytes());
            byte[] result = signature.sign();
            System.out.println("jdk ecdsa sign: " + Hex.encodeHexString(result));

            // 验证签名
            X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(ecPublicKey.getEncoded());
            keyFactory = KeyFactory.getInstance("EC");
            PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
            signature = Signature.getInstance("SHA1withECDSA");
            signature.initVerify(publicKey);
            signature.update(src.getBytes());
            boolean bool = signature.verify(result);
            System.out.println("jdk ecdsa: " + bool);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

二、 运行结果如下：

jdk ecdsa sign: 30460221009b80596c51ccdf19c5e8e825aca6d85e549a30ee72a1e9b094f7b3a8c8b9310902210098e8dcc6ea932142d8cd9dd80c08fff7359f796571f8a973d3ca6e2dc0931904
jdk ecdsa: true

友情链接