string password = "213978863940714";
string signatureAlgorithm = "SHA1WithRSA";
// Generate RSA key pair
var rsaGenerator = new RsaKeyPairGenerator();
var randomGenerator = new CryptoApiRandomGenerator();
var secureRandom = new SecureRandom(randomGenerator);
var keyParameters = new KeyGenerationParameters(secureRandom, 1024);
rsaGenerator.Init(keyParameters);
var keyPair = rsaGenerator.GenerateKeyPair();
// Generate certificate
var attributes = new Hashtable();
attributes[X509Name.E] = UserInfo.idCard;//设置dn信息的邮箱地址
attributes[X509Name.CN] = UserInfo.idCard;//设置证书的用户,也就是颁发给谁
attributes[X509Name.O] = "www.shwdztc.com";//设置证书的办法者
attributes[X509Name.C] = "Zh";//证书的语言
//这里是证书颁发者的信息
var ordering = new ArrayList();
ordering.Add(X509Name.E);
ordering.Add(X509Name.CN);
ordering.Add(X509Name.O);
ordering.Add(X509Name.C);
var certificateGenerator = new X509V3CertificateGenerator();
//设置证书序列化号
certificateGenerator.SetSerialNumber(BigInteger.ProbablePrime(120, new Random()));
//设置颁发者dn信息
certificateGenerator.SetIssuerDN(new X509Name(ordering, attributes));
//设置证书生效时间
certificateGenerator.SetNotBefore(DateTime.Today.Subtract(new TimeSpan(1, 0, 0, 0)));
//设置证书失效时间
certificateGenerator.SetNotAfter(DateTime.Today.AddDays(365));
//设置接受者dn信息
certificateGenerator.SetSubjectDN(new X509Name(ordering, attributes));
//设置证书的公钥
certificateGenerator.SetPublicKey(keyPair.Public);
//设置证书的加密算法
certificateGenerator.SetSignatureAlgorithm(signatureAlgorithm);
certificateGenerator.AddExtension(X509Extensions.BasicConstraints, true, new BasicConstraints(false));
certificateGenerator.AddExtension(X509Extensions.AuthorityKeyIdentifier, true, new AuthorityKeyIdentifier(SubjectPublicKeyInfoFactory.CreateSubjectPublicKeyInfo(keyPair.Public)));
certificateGenerator.AddExtension(X509Extensions.ExtendedKeyUsage.Id, false, new ExtendedKeyUsage(new ArrayList() { new DerObjectIdentifier("1.3.6.1.5.5.7.3.2") }));
//创建证书,如果需要cer格式的证书,到这里就可以了。如果是pfx格式的就需要加上访问密码
var x509Certificate = certificateGenerator.Generate(keyPair.Private);
byte[] pkcs12Bytes = DotNetUtilities.ToX509Certificate(x509Certificate).Export(X509ContentType.Pfx, password);
var certificate = new X509Certificate2(pkcs12Bytes, password);
certificate.PrivateKey = EncryHelper.ToDotNetKey((RsaPrivateCrtKeyParameters)keyPair.Private);
var array = certificate.Export(X509ContentType.Pfx, password);
var cerArray = certificate.Export(X509ContentType.Cert);
string path = HttpContext.Current.Server.MapPath("~/files/userword/Word/" + UserInfo.idCard + ".pfx");
string pathcer = HttpContext.Current.Server.MapPath("~/files/userword/Word/" + UserInfo.idCard + ".cer");
FileStream fsCA = new FileStream(path, FileMode.Create);
//将byte数组写入文件中
fsCA.Write(array, 0, array.Length);
fsCA.Close();
FileStream fscer = new FileStream(pathcer, FileMode.Create);
//将byte数组写入文件中
fscer.Write(cerArray, 0, cerArray.Length);
fscer.Close();