RSA加解密&RSA加验签

开发语言与私钥证书的关系如下：

开发语言	私钥格式	证书格式
JAVA	.key.p8	.crt
PHP	.key.pem	.cert.pem
.NET	.key.der	.crt
其它	.key.pem	.cert.pem

我们是java语言，工程property配置：
#商户私钥 PKCS#8标准的私钥
90000002.mer.prikey.path=cert/90000002.key.p8
#平台公钥 X.509证书
plat.cert.path=cert/umpay.cert.crt

RSA加密/RSA解密

获取公钥和私钥

import com.umpay.core.util.ProFileUtil;

import java.io.ByteArrayInputStream;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

public static PublicKey getPublicKey() throws Exception {

    byte[] b = ProFileUtil.getFileByte("plat.cert.path");

    ByteArrayInputStream bais = new ByteArrayInputStream(b);
    CertificateFactory cf = CertificateFactory.getInstance("X.509");
    X509Certificate x509Certificate = (X509Certificate) cf.generateCertificate(bais);

    byte[] keyBytes = x509Certificate.getPublicKey().getEncoded();
    X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(keyBytes);
    KeyFactory keyFactory = KeyFactory.getInstance("RSA");
    return keyFactory.generatePublic(x509KeySpec);
}

public static PrivateKey getPrivateKey(String merId) throws Exception {
    byte[] key = ProFileUtil.getFileByte(merId + ".mer.prikey.path");
    PKCS8EncodedKeySpec e = new PKCS8EncodedKeySpec(key);
    KeyFactory kf = KeyFactory.getInstance("RSA");
    return kf.generatePrivate(e);
}

RSA签名（加签/验签） 

原文地址：https://www.cnblogs.com/buguge/p/11769740.html