数字签名算法_DSA

DSS：数字签名标准

DSA:数字签名算法

DSA和RSA区别：

DSA签名和RSA签名Java jdk提供的实现代码基本一样，BC提供的没学学习过不知道啥情况。

直接上代码吧：

public class DemoDsa {
public static void jdkDSA(String data) {
// 初始化密钥
try {
KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("DSA");
keyPairGenerator.initialize(512);

KeyPair keyPair = keyPairGenerator.generateKeyPair();
//0. 获取公钥和密钥
DSAPublicKey dsaPublicKey = (DSAPublicKey) keyPair.getPublic();
DSAPrivateKey dsaPrivateKey = (DSAPrivateKey) keyPair.getPrivate();

//1.执行签名
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(dsaPrivateKey.getEncoded());
KeyFactory keyFactory = KeyFactory.getInstance("DSA");
PrivateKey privateKey = keyFactory.generatePrivate(pkcs8EncodedKeySpec);
Signature signature = Signature.getInstance("SHAwithDSA");
signature.initSign(privateKey);
signature.update(data.getBytes());
//加密后的结果
byte[] result = signature.sign();
//打印数据
StringBuilder hexString = new StringBuilder();
for (int i = 0; i < result.length; i++) {
if ((result[i] & 0xff) < 0x10)
hexString.append("0");
hexString.append(Integer.toHexString(0xFF & result[i]));
}
System.out.println("加密后的数据：" + hexString.toString().toLowerCase());

//3.验证签名
X509EncodedKeySpec x509EncodedKeySpec=new X509EncodedKeySpec(dsaPublicKey.getEncoded());
keyFactory=KeyFactory.getInstance("DSA");
PublicKey publicKey=keyFactory.generatePublic(x509EncodedKeySpec);
signature=Signature.getInstance("SHAwithDSA");
signature.initVerify(publicKey);
signature.update(data.getBytes());
//验证后的结果
boolean isOk=signature.verify(result);
System.out.println("验证结果："+isOk);
} catch (Exception e) {
e.printStackTrace();
}

}
}

调用这个签名：

jdkDSA("i love you");