数字签名.怎么从*.cer文件中获得私钥?

Question

现在在研究数字签名技术,基于.net平台,对生成的*.cer文件,可以读出公钥的xml形式,可是无法获的私钥的xml形式?有那位高手知道,指教小弟一下?

Answer 1

有一段参考代码发给大家也看一下.
using System;
using System.Security.Cryptography;
using System.Security.Permissions;
using System.IO;
using System.Security.Cryptography.X509Certificates;
public class CertInfo
{
    //Reads a file.
    internal static byte[] ReadFile(string fileName)
    {
        FileStream f = new FileStream(fileName, FileMode.Open, FileAccess.Read);
        int size = (int)f.Length;
        byte[] data = new byte[size];
        size = f.Read(data, 0, size);
        f.Close();
        return data;
    }
    //Main method begins here.
    public static void Main(string[] args)
    {
        //Test for correct number of arguments.
        //if (args.Length < 1)
        //{
        //    Console.WriteLine("Usage: CertInfo <filename>");
        //    return;
        //}
        try
        {
            X509Certificate2 x509 = new X509Certificate2();
            //Create X509Certificate2 object from .cer file.
            byte[] rawData = ReadFile("c:\\textWHX.cer");
            x509.Import(rawData);            //Print to console information contained in the certificate
            Console.WriteLine("{0}证书名称Subject: {1}{0}", Environment.NewLine, x509.Subject);
            Console.WriteLine("{0}证书颁发机构的名称Issuer: {1}{0}", Environment.NewLine, x509.Issuer);
            Console.WriteLine("{0}版本Version: {1}{0}", Environment.NewLine, x509.Version);
            Console.WriteLine("{0}证书生效的本地时间中的日期Valid Date: {1}{0}", Environment.NewLine, x509.NotBefore);
            Console.WriteLine("{0}该日期后证书不再有效Expiry Date: {1}{0}", Environment.NewLine, x509.NotAfter);
            Console.WriteLine("{0}证书的指纹Thumbprint: {1}{0}", Environment.NewLine, x509.Thumbprint);
            Console.WriteLine("{0}证书的序列号Serial Number: {1}{0}", Environment.NewLine, x509.SerialNumber);
            Console.WriteLine("{0}公钥标识符友好名称Friendly Name: {1}{0}", Environment.NewLine, x509.PublicKey.Oid.FriendlyName);
            Console.WriteLine("{0}公钥的ASN。1码Public Key Format: {1}{0}", Environment.NewLine, x509.PublicKey.EncodedKeyValue.Format(true));
            Console.WriteLine("{0}证书的原始数据的长度Raw Data Length: {1}{0}", Environment.NewLine, x509.RawData.Length);
            Console.WriteLine("{0}以文本格式显示X509证书Certificate to string: {1}{0}", Environment.NewLine, x509.ToString(true));            Console.WriteLine("{0}公钥以XML形式表式Certificate to XML String: {1}{0}", Environment.NewLine, x509.PublicKey.Key.ToXmlString(false));
            //Console.WriteLine("{0}私钥以XML形式表式Certificate to XML String: {1}{0}", Environment.NewLine, x509.PrivateKey.ToXmlString(false ));
            上面这注释的这一句老是出错?
            //Add the certificate to a X509Store.
            X509Store store = new X509Store();
            store.Open(OpenFlags.MaxAllowed);
            store.Add(x509);
            store.Close();
        }        catch (DirectoryNotFoundException)
        {
            Console.WriteLine("Error: The directory specified could not be found.");
        }
        catch (IOException)
        {
            Console.WriteLine("Error: A file in the directory could not be accessed.");
        }
        catch (NullReferenceException)
        {
            Console.WriteLine("File must be a .cer file. Program does not have access to that type of file.");
        }
    }}

Answer 2

标准可交换cer证书文件是不包含私钥的私人信息文件pfx里面才会包含有私钥

Answer 3

nod
不然那还叫什么私钥。