C#中RSA公钥和私钥的格式都是XML的,而在其他语言如java中,生成的RSA密钥就是普通的Base64字符串,所以需要将C#xml格式的密钥转换成普通的Base64字符串,同时也要实现Base64密钥字符串生成C#中xml格式的密钥.
安装 BouncyCastle 这个Nuget包
PM > Install-Package BouncyCastle
BouncyCastle项目网址
BouncyCastlegithub地址
构造一个RSAKeyConventer类
namespace RSA
{
using System;
using System.Security.Cryptography;
using Org.BouncyCastle.Asn1.Pkcs;
using Org.BouncyCastle.Math;
using Org.BouncyCastle.Pkcs;
using Org.BouncyCastle.Asn1.X509;
using Org.BouncyCastle.X509;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Crypto.Parameters;
public class RSAKeyConverter
{
/// <summary>
/// xml private key -> base64 private key string
/// </summary>
/// <param name="xmlPrivateKey"></param>
/// <returns></returns>
public static string FromXmlPrivateKey(string xmlPrivateKey)
{
string result = string.Empty;
using(RSACryptoServiceProvider rsa = new RSACryptoServiceProvider())
{
rsa.FromXmlString(xmlPrivateKey);
RSAParameters param = rsa.ExportParameters(true);
RsaPrivateCrtKeyParameters privateKeyParam = new RsaPrivateCrtKeyParameters(
new BigInteger(1, param.Modulus), new BigInteger(1, param.Exponent),
new BigInteger(1, param.D), new BigInteger(1, param.P),
new BigInteger(1, param.Q), new BigInteger(1, param.DP),
new BigInteger(1, param.DQ), new BigInteger(1, param.InverseQ));
PrivateKeyInfo privateKey = PrivateKeyInfoFactory.CreatePrivateKeyInfo(privateKeyParam);
result = Convert.ToBase64String(privateKey.ToAsn1Object().GetEncoded());
}
return result;
}
/// <summary>
/// xml public key -> base64 public key string
/// </summary>
/// <param name="xmlPublicKey"></param>
/// <returns></returns>
public static string FromXmlPublicKey(string xmlPublicKey)
{
string result = string.Empty;
using(RSACryptoServiceProvider rsa = new RSACryptoServiceProvider())
{
rsa.FromXmlString(xmlPublicKey);
RSAParameters p = rsa.ExportParameters(false);
RsaKeyParameters keyParams = new RsaKeyParameters(
false, new BigInteger(1,p.Modulus), new BigInteger(1, p.Exponent));
SubjectPublicKeyInfo publicKeyInfo = SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(keyParams);
result = Convert.ToBase64String(publicKeyInfo.ToAsn1Object().GetEncoded());
}
return result;
}
/// <summary>
/// base64 private key string -> xml private key
/// </summary>
/// <param name="privateKey"></param>
/// <returns></returns>
public static string ToXmlPrivateKey(string privateKey)
{
RsaPrivateCrtKeyParameters privateKeyParams =
PrivateKeyFactory.CreateKey(Convert.FromBase64String(privateKey)) as RsaPrivateCrtKeyParameters;
using(RSACryptoServiceProvider rsa = new RSACryptoServiceProvider())
{
RSAParameters rsaParams = new RSAParameters()
{
Modulus = privateKeyParams.Modulus.ToByteArrayUnsigned(),
Exponent = privateKeyParams.PublicExponent.ToByteArrayUnsigned(),
D = privateKeyParams.Exponent.ToByteArrayUnsigned(),
DP = privateKeyParams.DP.ToByteArrayUnsigned(),
DQ = privateKeyParams.DQ.ToByteArrayUnsigned(),
P = privateKeyParams.P.ToByteArrayUnsigned(),
Q = privateKeyParams.Q.ToByteArrayUnsigned(),
InverseQ = privateKeyParams.QInv.ToByteArrayUnsigned()
};
rsa.ImportParameters(rsaParams);
return rsa.ToXmlString(true);
}
}
/// <summary>
/// base64 public key string -> xml public key
/// </summary>
/// <param name="pubilcKey"></param>
/// <returns></returns>
public static string ToXmlPublicKey(string pubilcKey)
{
RsaKeyParameters p =
PublicKeyFactory.CreateKey(Convert.FromBase64String(pubilcKey)) as RsaKeyParameters;
using(RSACryptoServiceProvider rsa = new RSACryptoServiceProvider())
{
RSAParameters rsaParams = new RSAParameters
{
Modulus = p.Modulus.ToByteArrayUnsigned(),
Exponent = p.Exponent.ToByteArrayUnsigned()
};
rsa.ImportParameters(rsaParams);
return rsa.ToXmlString(false);
}
}
}
}
