ECDSA
例如微软产品的序列号的验证算法。
Elliptic Curve Digital Signature Algorithm，椭圆曲线数字签名算法。
速度快，强度高，签名短
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密钥长度 112～571 默认 256
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NONEwithECDSA 签名长度：128 实现方：JDK/BC
RIPEMD160withECDSA 签名长度：160 实现方：BC
SHA1withECDSA 签名长度：160 实现方：JDK/BC
SHA224withECDSA 签名长度：224 实现方：BC
SHA384withECDSA 签名长度：384 实现方：JDK/BC
SHA512withECDSA 签名长度：512 实现方：JDK/BC
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代码：
1 package ECDSA;
2
3 import com.sun.org.apache.xerces.internal.impl.dv.util.HexBin;
4
5 import java.security.*;
6 import java.security.interfaces.ECPrivateKey;
7 import java.security.interfaces.ECPublicKey;
8 import java.security.spec.PKCS8EncodedKeySpec;
9 import java.security.spec.X509EncodedKeySpec;
10
11 public class Ecdsa {
12 private static String src = "hello berber" ;
13 public static void main(String []args){
14 jdkECDSA();
15 }
16 public static void jdkECDSA(){
17 // 1.初始化密钥
18 try{
19 KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("EC");
20 keyPairGenerator.initialize(256);
21 KeyPair keyPair = keyPairGenerator.generateKeyPair() ;
22 ECPublicKey ecPublicKey = (ECPublicKey)keyPair.getPublic() ;
23 ECPrivateKey ecPrivateKey = (ECPrivateKey)keyPair.getPrivate() ;
24 // 执行签名
25 PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(ecPrivateKey.getEncoded());
26 KeyFactory keyFactory = KeyFactory.getInstance("EC") ;
27 PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec) ;
28 Signature signature = Signature.getInstance("SHA1withECDSA");
29 signature.initSign(privateKey);
30 signature.update(src.getBytes());
31 byte []arr = signature.sign();
32 System.out.println("jdk ecdsa sign :"+ HexBin.encode(arr));
33 // 验证签名
34 X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(ecPublicKey.getEncoded());
35 keyFactory = KeyFactory.getInstance("EC");
36 PublicKey publicKey = keyFactory.generatePublic(x509EncodedKeySpec);
37 signature = Signature.getInstance("SHA1withECDSA");
38 signature.initVerify(publicKey);
39 signature.update(src.getBytes());
40 boolean bool = signature.verify(arr);
41 System.out.println("jdk ecdsa verify:"+bool);
42 }catch(Exception e){
43
44 }
45 }
46 }
