/*

* Copyright 2014-2023 The GmSSL Project. All Rights Reserved.

*

* Licensed under the Apache License, Version 2.0 (the License); you may

* not use this file except in compliance with the License.

*

* http://www.apache.org/licenses/LICENSE-2.0

*/

import org.gmssl.Sm2Key;

import org.gmssl.Sm2Signature;

import org.gmssl.Sm3;

import org.gmssl.Random;

public class Sm2Example {

public static void main(String[] args) {

int i;

Sm2Key sm2_key = new Sm2Key();

sm2_key.generateKey();

byte[] privateKeyInfo = sm2_key.exportPrivateKeyInfoDer();

System.out.printf("PrivateKeyInfo: ");

for (i = 0; i < privateKeyInfo.length; i++) {

System.out.printf("%02x", privateKeyInfo[i]);

}

System.out.print("\n");

byte[] publicKeyInfo = sm2_key.exportPublicKeyInfoDer();

System.out.printf("PrivateKeyInfo: ");

for (i = 0; i < publicKeyInfo.length; i++) {

System.out.printf("%02x", publicKeyInfo[i]);

}

System.out.print("\n");

Sm2Key priKey = new Sm2Key();

priKey.importPrivateKeyInfoDer(privateKeyInfo);

Sm2Key pubKey = new Sm2Key();

pubKey.importPublicKeyInfoDer(publicKeyInfo);

priKey.exportEncryptedPrivateKeyInfoPem("Password", "sm2.pem");

pubKey.exportPublicKeyInfoPem("sm2pub.pem");

priKey.importEncryptedPrivateKeyInfoPem("Password", "sm2.pem");

pubKey.importPublicKeyInfoPem("sm2pub.pem");

byte[] z = pubKey.computeZ(Sm2Key.DEFAULT_ID);

System.out.printf("Z: ");

for (i = 0; i < z.length; i++) {

System.out.printf("%02x", z[i]);

}

System.out.print("\n");

Random rng = new Random();

byte[] dgst = rng.randBytes(Sm3.DIGEST_SIZE);

byte[] sig = priKey.sign(dgst);

boolean verify_ret = pubKey.verify(dgst, sig);

System.out.println("Verify result = " + verify_ret);

byte[] ciphertext = pubKey.encrypt("abc".getBytes());

byte[] plaintext = priKey.decrypt(ciphertext);

System.out.printf("Plaintext : ");

for (i = 0; i < plaintext.length; i++) {

System.out.printf("%02x", plaintext[i]);

}

System.out.print("\n");

Sm2Signature sign = new Sm2Signature(priKey, Sm2Key.DEFAULT_ID, true);

sign.update("abc".getBytes());

sig = sign.sign();

Sm2Signature verify = new Sm2Signature(pubKey, Sm2Key.DEFAULT_ID, false);

verify.update("abc".getBytes());

verify_ret = verify.verify(sig);

System.out.println("Verify result = " + verify_ret);

}

}