数字签名算法--3.ECDSA

package Imooc;

import java.security.KeyFactory;

import java.security.KeyPair;

import java.security.KeyPairGenerator;

import java.security.NoSuchAlgorithmException;

import java.security.PrivateKey;

import java.security.PublicKey;

import java.security.interfaces.ECPrivateKey;

import java.security.interfaces.ECPublicKey;

import java.security.spec.PKCS8EncodedKeySpec;

import java.security.spec.X509EncodedKeySpec;

import java.security.Signature;

import com.sun.org.apache.xerces.internal.impl.dv.util.HexBin;

//import com.sun.org.apache.bcel.internal.classfile.Signature;

public class ImoocECDSA {

private static String src = "imooc security ecdsa";

public static void main(String[] args) {

jdkECDSA();

}

//java7以后使用

public static void jdkECDSA()

{

try {

KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("EC");

keyPairGenerator.initialize(256);

KeyPair keyPair = keyPairGenerator.generateKeyPair();

ECPublicKey ecPublicKey = (ECPublicKey)keyPair.getPublic();

ECPrivateKey ecPrivateKey = (ECPrivateKey)keyPair.getPrivate();

PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(ecPrivateKey.getEncoded());

KeyFactory keyFactory = KeyFactory.getInstance("EC");

PrivateKey privateKey =keyFactory.generatePrivate(pkcs8EncodedKeySpec);

Signature  signature = Signature.getInstance("SHA1withECDSA");

signature.initSign(privateKey);

signature.update(src.getBytes());

byte[] result = signature.sign();

System.out.println("jdk ecdsa sign:"+HexBin.encode(result));

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 verify:"+bool);

} catch (Exception e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

}