using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Security.Cryptography.X509Certificates;
using System.Security.Cryptography;
namespace Kad.ThridParty.ChinaPayWap
{
/// <summary>
/// 非对称RSA加解密，私钥加密/公钥解密
/// 仅用于银联Wap支付报文收发
/// By : EnVon(E旺) 2013-08-20
/// </summary>
internal class RSAHelper
{
/// <summary>
/// RSA加密（用私钥加密哟）
/// </summary>
/// <param name="key">私钥</param>
/// <param name="data">待加密的数据</param>
/// <returns></returns>
public static byte[] Encrypt(String key, byte[] data)
{
//由密钥xml取得RSA对象
RSACryptoServiceProvider rsa
= new RSACryptoServiceProvider
(); rsa.FromXmlString(key);
//取得加密时使用的2个参数
RSAParameters par = rsa.ExportParameters(true);
BigInteger mod
= new BigInteger
(par
.Modulus); BigInteger ep
= new BigInteger
(par
.D); //计算填充长度
int mLen = par.Modulus.Length;
int fLen = mLen - data.Length - 3;
//组建bytes
List
<byte> lis
= new List
<byte>(); lis.Add(0x00);
lis.Add(0x01);//兼容java
for (int i = 0; i < fLen; i++) lis.Add(0xff);
lis.Add(0x00);
lis.AddRange(data);
byte[] bytes = lis.ToArray();
//加密就这么简单？
BigInteger m
= new BigInteger
(bytes
); BigInteger c = m.modPow(ep, mod);
return c.getBytes();
}
/// <summary>
/// RSA解密（用公钥解密哟）
/// </summary>
/// <param name="key">公钥</param>
/// <param name="data">待解密的数据</param>
/// <returns></returns>
public static byte[] Decrypt(String key, byte[] data)
{
//由密钥xml取得RSA对象
RSACryptoServiceProvider rsa
= new RSACryptoServiceProvider
(); rsa.FromXmlString(key);
//取得解密时使用的2个参数
RSAParameters par = rsa.ExportParameters(false);
BigInteger mod
= new BigInteger
(par
.Modulus); BigInteger ep
= new BigInteger
(par
.Exponent); //解密？
BigInteger m
= new BigInteger
(data
); BigInteger c = m.modPow(ep, mod);
byte[] bytes = c.getBytes();
//去掉填充域（头部可能填充了一段0xff）
byte flag = 0;
for (int i = 1/*我从1开始啦*/; i < bytes.Length; i++)
{
if (bytes[i] == flag && i != (bytes.Length - 1))
{
byte[] retBytes
= new byte[bytes
.Length - i
- 1]; Array.Copy(bytes, i + 1, retBytes, 0, retBytes.Length);
return retBytes;
}
}
return bytes;
}
/// <summary>
/// 取得证书私钥
/// </summary>
/// <param name="pfxPath">证书的绝对路径</param>
/// <param name="password">访问证书的密码</param>
/// <returns></returns>
public static String GetPrivateKey(string pfxPath, string password)
{
X509Certificate2 pfx
= new X509Certificate2
(pfxPath, password, X509KeyStorageFlags
.Exportable); string privateKey = pfx.PrivateKey.ToXmlString(true);
return privateKey;
}
/// <summary>
/// 取得证书的公钥
/// </summary>
/// <param name="cerPath">证书的绝对路径</param>
/// <returns></returns>
public static String GetPublicKey(string cerPath)
{
X509Certificate2 cer
= new X509Certificate2
(cerPath
); string publicKey = cer.PublicKey.Key.ToXmlString(false);
return publicKey;
}
}
}