ECDSA 实现

/*** 2009-10-10*/
package org.zlex.chapter09_3;import java.math.BigInteger;
import java.security.Key;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.SecureRandom;
import java.security.Security;
import java.security.Signature;
import java.security.interfaces.ECPrivateKey;
import java.security.interfaces.ECPublicKey;
import java.security.spec.ECFieldFp;
import java.security.spec.ECParameterSpec;
import java.security.spec.ECPoint;
import java.security.spec.EllipticCurve;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;
import java.util.HashMap;
import java.util.Map;import org.bouncycastle.jce.provider.BouncyCastleProvider;/*** ECDSA安全编码组件* * @author 梁栋* @version 1.0* @since 1.0*/
public abstract class ECDSACoder {/*** 数字签名 密钥算法*/private static final String KEY_ALGORITHM = "ECDSA";/*** 数字签名 签名/验证算法* * Bouncy Castle支持以下7种算法* NONEwithECDSA * RIPEMD160withECDSA * SHA1withECDSA* SHA224withECDSA * SHA256withECDSA * SHA384withECDSA * SHA512withECDSA*/private static final String SIGNATURE_ALGORITHM = "SHA512withECDSA";/*** 公钥*/private static final String PUBLIC_KEY = "ECDSAPublicKey";/*** 私钥*/private static final String PRIVATE_KEY = "ECDSAPrivateKey";/*** 初始化密钥* * @return Map 密钥Map* @throws Exception*/public static Map<String, Object> initKey() throws Exception {// 加入BouncyCastleProvider支持Security.addProvider(new BouncyCastleProvider());BigInteger p = new BigInteger("883423532389192164791648750360308885314476597252960362792450860609699839");ECFieldFp ecFieldFp = new ECFieldFp(p);BigInteger a = new BigInteger("7fffffffffffffffffffffff7fffffffffff8000000000007ffffffffffc",16);BigInteger b = new BigInteger("6b016c3bdcf18941d0d654921475ca71a9db2fb27d1d37796185c2942c0a",16);EllipticCurve ellipticCurve = new EllipticCurve(ecFieldFp, a, b);BigInteger x = new BigInteger("110282003749548856476348533541186204577905061504881242240149511594420911");BigInteger y = new BigInteger("869078407435509378747351873793058868500210384946040694651368759217025454");ECPoint g = new ECPoint(x, y);BigInteger n = new BigInteger("883423532389192164791648750360308884807550341691627752275345424702807307");ECParameterSpec ecParameterSpec = new ECParameterSpec(ellipticCurve, g,n, 1);// 实例化密钥对儿生成器KeyPairGenerator kpg = KeyPairGenerator.getInstance(KEY_ALGORITHM);// 初始化密钥对儿生成器kpg.initialize(ecParameterSpec, new SecureRandom());// 生成密钥对儿KeyPair keypair = kpg.generateKeyPair();ECPublicKey publicKey = (ECPublicKey) keypair.getPublic();ECPrivateKey privateKey = (ECPrivateKey) keypair.getPrivate();// 封装密钥Map<String, Object> map = new HashMap<String, Object>(2);map.put(PUBLIC_KEY, publicKey);map.put(PRIVATE_KEY, privateKey);return map;}/*** 取得私钥* * @param keyMap*            密钥Map* @return byte[] 私钥* @throws Exception*/public static byte[] getPrivateKey(Map<String, Object> keyMap)throws Exception {Key key = (Key) keyMap.get(PRIVATE_KEY);return key.getEncoded();}/*** 取得公钥* * @param keyMap*            密钥Map* @return byte[] 公钥* @throws Exception*/public static byte[] getPublicKey(Map<String, Object> keyMap)throws Exception {Key key = (Key) keyMap.get(PUBLIC_KEY);return key.getEncoded();}/*** 签名* * @param data*            待签名数据* @param privateKey*            私钥* @return byte[] 数字签名* @throws Exception*/public static byte[] sign(byte[] data, byte[] privateKey) throws Exception {// 加入BouncyCastleProvider支持Security.addProvider(new BouncyCastleProvider());// 转换私钥材料PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(privateKey);// 实例化密钥工厂KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);// 取私钥匙对象PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);// 实例化SignatureSignature signature = Signature.getInstance(SIGNATURE_ALGORITHM);// 初始化Signaturesignature.initSign(priKey);// 更新signature.update(data);// 签名return signature.sign();}/*** 校验* * @param data*            待校验数据* @param publicKey*            公钥* @param sign*            数字签名* @return boolean 校验成功返回true 失败返回false* @throws Exception* */public static boolean verify(byte[] data, byte[] publicKey, byte[] sign)throws Exception {// 加入BouncyCastleProvider支持Security.addProvider(new BouncyCastleProvider());// 转换公钥材料X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicKey);// 实例化密钥工厂KeyFactory keyFactory = KeyFactory.getInstance(KEY_ALGORITHM);// 生成公钥PublicKey pubKey = keyFactory.generatePublic(keySpec);// 实例化SignatureSignature signature = Signature.getInstance(SIGNATURE_ALGORITHM);// 初始化Signaturesignature.initVerify(pubKey);// 更新signature.update(data);// 验证return signature.verify(sign);}
}

ECDSA 示例

/*** 2008-6-11*/
package org.zlex.chapter09_3;import static org.junit.Assert.*;import java.util.Map;import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.junit.Before;
import org.junit.Test;/*** ECDSA数字签名校验* * @author 梁栋* @version 1.0*/
public class ECDSACoderTest {/*** 公钥*/private byte[] publicKey;/*** 私钥*/private byte[] privateKey;/*** 初始化密钥* * @throws Exception*/@Beforepublic void initKey() throws Exception {Map<String, Object> keyMap = ECDSACoder.initKey();publicKey = ECDSACoder.getPublicKey(keyMap);privateKey = ECDSACoder.getPrivateKey(keyMap);System.err.println("公钥: \n" + Base64.encodeBase64String(publicKey));System.err.println("私钥： \n" + Base64.encodeBase64String(privateKey));}/*** 校验* * @throws Exception*/@Testpublic void test() throws Exception {String inputStr = "ECDSA 数字签名";byte[] data = inputStr.getBytes();// 产生签名byte[] sign = ECDSACoder.sign(data, privateKey);System.err.println("签名:\r" + Hex.encodeHexString(sign));// 验证签名boolean status = ECDSACoder.verify(data, publicKey, sign);System.err.println("状态:\r" + status);assertTrue(status);}}