@myloveCc commented on Sun Aug 20 2017

rsa.ToXmlString(true) is not supported on .NET Core 2.0

 var rsa = RSA.Create(2048);
 var privateKey = rsa.ToXmlString(true);    // //not supported exception

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@bartonjs commented on Mon Aug 21 2017

Yep. In .NET Framework networking, XML, and cryptography all live in one library (mscorlib). In .NET Core they’re in three separate libraries, and making this method work requires a circle:

• XML needs networking, because (even though we discourage it) DTDs can initiate downloads.
• Networking needs cryptography because TLS/https have X.509 certificates.
• Cryptography needs XML for ToXmlString/FromXmlString.

The easiest link to snip is the ToXmlString/FromXmlString methods.

Technically ToXmlString can be written without XML (like in .NET Framework’s implementation, but FromXmlString requires an XML parser.

My recommendation would be to make a public static string ToXmlString(this RSAParameters rsaParameters) method, and a public static RSAParameters FromXmlString(string xml) method; borrowing from NetFx and CoreFx’s SignedXml; and to ultimately try moving off of the XML representations.

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@myloveCc commented on Mon Aug 21 2017

This feature is not difficult, and I have been achieved in my project。

using System;
using System.Security.Cryptography;
using System.Xml;
using Newtonsoft.Json;
using NETCore.Encrypt.Shared;
using NETCore.Encrypt.Internal;

namespace NETCore.Encrypt.Extensions.Internal
{

    internal static class RSAKeyExtensions
    {
        #region JSON
        internal static void FromJsonString(this RSA rsa, string jsonString)
        {
            Check.Argument.IsNotEmpty(jsonString, nameof(jsonString));
            try
            {
                var paramsJson = JsonConvert.DeserializeObject<RSAParametersJson>(jsonString);

                RSAParameters parameters = new RSAParameters();

                parameters.Modulus = paramsJson.Modulus != null ? Convert.FromBase64String(paramsJson.Modulus) : null;
                parameters.Exponent = paramsJson.Exponent != null ? Convert.FromBase64String(paramsJson.Exponent) : null;
                parameters.P = paramsJson.P != null ? Convert.FromBase64String(paramsJson.P) : null;
                parameters.Q = paramsJson.Q != null ? Convert.FromBase64String(paramsJson.Q) : null;
                parameters.DP = paramsJson.DP != null ? Convert.FromBase64String(paramsJson.DP) : null;
                parameters.DQ = paramsJson.DQ != null ? Convert.FromBase64String(paramsJson.DQ) : null;
                parameters.InverseQ = paramsJson.InverseQ != null ? Convert.FromBase64String(paramsJson.InverseQ) : null;
                parameters.D = paramsJson.D != null ? Convert.FromBase64String(paramsJson.D) : null;
                rsa.ImportParameters(parameters);
            }
            catch
            {
                throw new Exception("Invalid JSON RSA key.");
            }
        }

        internal static string ToJsonString(this RSA rsa, bool includePrivateParameters)
        {
            RSAParameters parameters = rsa.ExportParameters(includePrivateParameters);

            var parasJson = new RSAParametersJson()
            {
                Modulus = parameters.Modulus != null ? Convert.ToBase64String(parameters.Modulus) : null,
                Exponent = parameters.Exponent != null ? Convert.ToBase64String(parameters.Exponent) : null,
                P = parameters.P != null ? Convert.ToBase64String(parameters.P) : null,
                Q = parameters.Q != null ? Convert.ToBase64String(parameters.Q) : null,
                DP = parameters.DP != null ? Convert.ToBase64String(parameters.DP) : null,
                DQ = parameters.DQ != null ? Convert.ToBase64String(parameters.DQ) : null,
                InverseQ = parameters.InverseQ != null ? Convert.ToBase64String(parameters.InverseQ) : null,
                D = parameters.D != null ? Convert.ToBase64String(parameters.D) : null
            };

            return JsonConvert.SerializeObject(parasJson);
        }
        #endregion

        #region XML

        public static void FromXmlString(this RSA rsa, string xmlString)
        {
            RSAParameters parameters = new RSAParameters();

            XmlDocument xmlDoc = new XmlDocument();
            xmlDoc.LoadXml(xmlString);

            if (xmlDoc.DocumentElement.Name.Equals("RSAKeyValue"))
            {
                foreach (XmlNode node in xmlDoc.DocumentElement.ChildNodes)
                {
                    switch (node.Name)
                    {
                        case "Modulus": parameters.Modulus = (string.IsNullOrEmpty(node.InnerText) ? null : Convert.FromBase64String(node.InnerText)); break;
                        case "Exponent": parameters.Exponent = (string.IsNullOrEmpty(node.InnerText) ? null : Convert.FromBase64String(node.InnerText)); break;
                        case "P": parameters.P = (string.IsNullOrEmpty(node.InnerText) ? null : Convert.FromBase64String(node.InnerText)); break;
                        case "Q": parameters.Q = (string.IsNullOrEmpty(node.InnerText) ? null : Convert.FromBase64String(node.InnerText)); break;
                        case "DP": parameters.DP = (string.IsNullOrEmpty(node.InnerText) ? null : Convert.FromBase64String(node.InnerText)); break;
                        case "DQ": parameters.DQ = (string.IsNullOrEmpty(node.InnerText) ? null : Convert.FromBase64String(node.InnerText)); break;
                        case "InverseQ": parameters.InverseQ = (string.IsNullOrEmpty(node.InnerText) ? null : Convert.FromBase64String(node.InnerText)); break;
                        case "D": parameters.D = (string.IsNullOrEmpty(node.InnerText) ? null : Convert.FromBase64String(node.InnerText)); break;
                    }
                }
            }
            else
            {
                throw new Exception("Invalid XML RSA key.");
            }

            rsa.ImportParameters(parameters);
        }

        public static string ToXmlString(this RSA rsa, bool includePrivateParameters)
        {
            RSAParameters parameters = rsa.ExportParameters(includePrivateParameters);

            return string.Format("<RSAKeyValue><Modulus>{0}</Modulus><Exponent>{1}</Exponent><P>{2}</P><Q>{3}</Q><DP>{4}</DP><DQ>{5}</DQ><InverseQ>{6}</InverseQ><D>{7}</D></RSAKeyValue>",
                  parameters.Modulus != null ? Convert.ToBase64String(parameters.Modulus) : null,
                  parameters.Exponent != null ? Convert.ToBase64String(parameters.Exponent) : null,
                  parameters.P != null ? Convert.ToBase64String(parameters.P) : null,
                  parameters.Q != null ? Convert.ToBase64String(parameters.Q) : null,
                  parameters.DP != null ? Convert.ToBase64String(parameters.DP) : null,
                  parameters.DQ != null ? Convert.ToBase64String(parameters.DQ) : null,
                  parameters.InverseQ != null ? Convert.ToBase64String(parameters.InverseQ) : null,
                  parameters.D != null ? Convert.ToBase64String(parameters.D) : null);
        }

        #endregion
    }
}

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@Petermarcu commented on Wed Aug 30 2017

@danmosemsft can you get this moved over to dotnet/corefx to be tracked as an issue there?