有没有知道怎样用C语言来写RSA加密算法的代码的？？？谢谢

#region RSA的加密函数 //##############################################################################
//RSA 方式加密
//说明KEY必须是XML的行式,返回的是字符串
//在有一点需要说明！！该加密方式有 长度 限制的！！
//##############################################################################

//RSA的加密函数 string public string RSAEncrypt(string xmlPublicKey, string m_strEncryptString)
{

byte[] PlainTextBArray; byte[] CypherTextBArray;
string Result;
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
rsa.FromXmlString(xmlPublicKey);
PlainTextBArray = (new UnicodeEncoding()).GetBytes(m_strEncryptString);
CypherTextBArray = rsa.Encrypt(PlainTextBArray, false);
Result = Convert.ToBase64String(CypherTextBArray);
return Result;

} //RSA的加密函数 byte[]
public string RSAEncrypt(string xmlPublicKey, byte[] EncryptString)
{

byte[] CypherTextBArray; string Result;
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
rsa.FromXmlString(xmlPublicKey);
CypherTextBArray = rsa.Encrypt(EncryptString, false);
Result = Convert.ToBase64String(CypherTextBArray);
return Result;

} #endregion
#region RSA的解密函数 //RSA的解密函数 string
public string RSADecrypt(string xmlPrivateKey, string m_strDecryptString)
{
byte[] PlainTextBArray;
byte[] DypherTextBArray;
string Result;
System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
rsa.FromXmlString(xmlPrivateKey);
PlainTextBArray = Convert.FromBase64String(m_strDecryptString);
DypherTextBArray = rsa.Decrypt(PlainTextBArray, false);
Result = (new UnicodeEncoding()).GetString(DypherTextBArray);
return Result;

}
//RSA的解密函数 byte public string RSADecrypt(string xmlPrivateKey, byte[] DecryptString)
{
byte[] DypherTextBArray;
string Result;
System.Security.Cryptography.RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
rsa.FromXmlString(xmlPrivateKey);
DypherTextBArray = rsa.Decrypt(DecryptString, false);
Result = (new UnicodeEncoding()).GetString(DypherTextBArray);
return Result;

} #endregion
#endregion