资源介绍
java中使用公钥加密私钥解密原理.
KeyGenerater类：
public class KeyGenerater { private byte[] priKey; private byte[] pubKey; public
void generater() { try { KeyPairGenerator keygen = KeyPairGenerator
.getInstance("RSA"); SecureRandom secrand = new SecureRandom();
secrand.setSeed("www.川江号子.cn".getBytes()); // 初始化随机产生器
keygen.initialize(1024, secrand);
KeyPair keys = keygen.genKeyPair();
PublicKey pubkey = keys.getPublic();
PrivateKey prikey = keys.getPrivate()
pubKey = Base64.encodeToByte(pubkey.getEncoded());
priKey = Base64.encodeToByte(prikey.getEncoded());
System.out.println("pubKey = " + new String(pubKey));
System.out.println("priKey = " + new String(priKey));
} catch
(java.lang.Exception e) {
System.out.println("生成密钥对失败");
e.printStackTrace();
}
}
public byte[] getPriKey() {
return priKey;
}
public byte[] getPubKey() {
return pubKey;
}
}
Signaturer 类：
public class Signaturer {
public static byte[] sign(byte[] priKeyText, String plainText) {
try {
PKCS8EncodedKeySpec priPKCS8 = new PKCS8EncodedKeySpec(Base64.decode(priKeyText));
KeyFactory keyf = KeyFactory.getInstance("RSA");
PrivateKey prikey = keyf.generatePrivate(priPKCS8);
// 用私钥对信息生成数字签名
Signature signet = java.security.Signature.getInstance("MD5withRSA");
signet.initSign(prikey);
signet.update(plainText.getBytes());
byte[] signed = Base64.encodeToByte(signet.sign());
return signed;
catch (java.lang.Exception e) {
System.out.println("签名失败");
e.printStackTrace();
}
return null;
}
}
SignProvider 类：
public class SignProvider {
private SignProvider() {
}
public static boolean verify(byte[] pubKeyText, String plainText,
byte[] signText) {
try {
// 解密由base64编码的公钥,并构造X509EncodedKeySpec对象
X509EncodedKeySpec bobPubKeySpec = new
X509EncodedKeySpec(Base64.decode(pubKeyText));
// RSA对称加密算法
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
// 取公钥匙对象
PublicKey pubKey = keyFactory.generatePublic(bobPubKeySpec);
// 解密由base64编码的数字签名
byte[] signed = Base64.decode(signText);
Signature signatureChecker = Signature.getInstance("MD5withRSA");
signatureChecker.initVerify(pubKey);
signatureChecker.update(plainText.getBytes())
// 验证签名是否正常
if
(signatureChecker.verify(signed))return true;
return false;
} catch (Throwable e) {
System.out.println("校验签名失败");
e.printStackTrace();
return false;
}
}
}