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RS256Signer.sln

+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.12.35506.116 d17.12
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{00D1A9C2-B5F0-4AF3-8072-F6C62B433612}") = "RS256Signer", "RS256Signer\RS256Signer.sqlproj", "{71C0326E-885D-4A56-9557-94DE18C4CCB6}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{71C0326E-885D-4A56-9557-94DE18C4CCB6}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{71C0326E-885D-4A56-9557-94DE18C4CCB6}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{71C0326E-885D-4A56-9557-94DE18C4CCB6}.Debug|Any CPU.Deploy.0 = Debug|Any CPU
+		{71C0326E-885D-4A56-9557-94DE18C4CCB6}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{71C0326E-885D-4A56-9557-94DE18C4CCB6}.Release|Any CPU.Build.0 = Release|Any CPU
+		{71C0326E-885D-4A56-9557-94DE18C4CCB6}.Release|Any CPU.Deploy.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+EndGlobal

RS256Signer/RS256Signer.sqlproj

+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003" ToolsVersion="4.0">
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <Name>RS256Signer</Name>
+    <SchemaVersion>2.0</SchemaVersion>
+    <ProjectVersion>4.1</ProjectVersion>
+    <ProjectGuid>{71c0326e-885d-4a56-9557-94de18c4ccb6}</ProjectGuid>
+    <DSP>Microsoft.Data.Tools.Schema.Sql.Sql160DatabaseSchemaProvider</DSP>
+    <OutputType>Database</OutputType>
+    <RootPath>
+    </RootPath>
+    <RootNamespace>RS256Signer</RootNamespace>
+    <AssemblyName>RS256Signer</AssemblyName>
+    <ModelCollation>1033, CI</ModelCollation>
+    <DefaultFileStructure>BySchemaAndSchemaType</DefaultFileStructure>
+    <DeployToDatabase>True</DeployToDatabase>
+    <TargetFrameworkVersion>v4.7.2</TargetFrameworkVersion>
+    <TargetLanguage>CS</TargetLanguage>
+    <AppDesignerFolder>Properties</AppDesignerFolder>
+    <SqlServerVerification>False</SqlServerVerification>
+    <IncludeCompositeObjects>True</IncludeCompositeObjects>
+    <TargetDatabaseSet>True</TargetDatabaseSet>
+    <TargetFrameworkProfile />
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <OutputPath>bin\Release\</OutputPath>
+    <BuildScriptName>$(MSBuildProjectName).sql</BuildScriptName>
+    <TreatWarningsAsErrors>False</TreatWarningsAsErrors>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <DefineDebug>false</DefineDebug>
+    <DefineTrace>true</DefineTrace>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <OutputPath>bin\Debug\</OutputPath>
+    <BuildScriptName>$(MSBuildProjectName).sql</BuildScriptName>
+    <TreatWarningsAsErrors>false</TreatWarningsAsErrors>
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <DefineDebug>true</DefineDebug>
+    <DefineTrace>true</DefineTrace>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <PropertyGroup>
+    <VisualStudioVersion Condition="'$(VisualStudioVersion)' == ''">11.0</VisualStudioVersion>
+    <!-- Default to the v11.0 targets path if the targets file for the current VS version is not found -->
+    <SSDTExists Condition="Exists('$(MSBuildExtensionsPath)\Microsoft\VisualStudio\v$(VisualStudioVersion)\SSDT\Microsoft.Data.Tools.Schema.SqlTasks.targets')">True</SSDTExists>
+    <VisualStudioVersion Condition="'$(SSDTExists)' == ''">11.0</VisualStudioVersion>
+  </PropertyGroup>
+  <Import Condition="'$(SQLDBExtensionsRefPath)' != ''" Project="$(SQLDBExtensionsRefPath)\Microsoft.Data.Tools.Schema.SqlTasks.targets" />
+  <Import Condition="'$(SQLDBExtensionsRefPath)' == ''" Project="$(MSBuildExtensionsPath)\Microsoft\VisualStudio\v$(VisualStudioVersion)\SSDT\Microsoft.Data.Tools.Schema.SqlTasks.targets" />
+  <ItemGroup>
+    <Folder Include="Properties" />
+  </ItemGroup>
+  <ItemGroup>
+    <Reference Include="System" />
+    <Reference Include="System.Data" />
+    <Reference Include="System.Xml" />
+    <Reference Include="BouncyCastle.Crypto">
+      <HintPath>..\..\..\Users\droid\.nuget\packages\portable.bouncycastle\1.9.0\lib\net40\BouncyCastle.Crypto.dll</HintPath>
+    </Reference>
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="SqlStoredProcedure1.cs" />
+  </ItemGroup>
+</Project>
\ No newline at end of file

RS256Signer/SqlStoredProcedure1.cs

+using System;
+using System.Data;
+using System.Data.SqlClient;
+using System.Data.SqlTypes;
+using System.IO;
+using System.Security.Cryptography;
+using System.Text;
+using Microsoft.SqlServer.Server;
+using Org.BouncyCastle.OpenSsl;
+using Org.BouncyCastle.Crypto;
+using Org.BouncyCastle.Security;
+using Org.BouncyCastle.Crypto.Parameters;
+using Org.BouncyCastle.Math;
+
+public partial class RS256Signer
+{
+    [SqlProcedure]
+    public static void RS256Sign(SqlString InData, SqlString secret, out SqlString signature)
+    {
+        string Data = GetValue(InData);
+        string Key = GetValue(secret);
+        signature = SqlString.Null;
+
+        
+        ASCIIEncoding ByteConverter = new ASCIIEncoding();
+
+        RSA rsa = RSA.Create();
+
+        rsa.ImportParameters(ImportPrivateKey(Key));
+
+        byte[] buffer = ByteConverter.GetBytes(Data);
+
+        byte[] sign = rsa.SignData(buffer, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);  // Pss Pkcs1
+
+        signature = Convert.ToBase64String(sign);
+
+    }
+
+    private static string GetValue(SqlString sqlValue)
+    {
+        return sqlValue.IsNull ? null : sqlValue.Value;
+    }
+
+    private static int? GetValue(SqlInt32 sqlValue)
+    {
+        return sqlValue.IsNull ? null : (int?)sqlValue.Value;
+    }
+    private static byte[] GetValue(SqlBinary sqlValue)
+    {
+        return sqlValue.IsNull ? null : sqlValue.Value;
+    }
+
+    public static RSAParameters ImportPrivateKey(string pem)
+    {
+
+        PemReader pr = new PemReader(new StringReader(pem));
+        RsaPrivateCrtKeyParameters privKey = (RsaPrivateCrtKeyParameters)pr.ReadObject();
+        RSAParameters rp = new RSAParameters();
+        rp.Modulus = privKey.Modulus.ToByteArrayUnsigned();
+        rp.Exponent = privKey.PublicExponent.ToByteArrayUnsigned();
+        rp.P = privKey.P.ToByteArrayUnsigned();
+        rp.Q = privKey.Q.ToByteArrayUnsigned();
+        rp.D = ConvertRSAParametersField(privKey.Exponent, rp.Modulus.Length);
+        rp.DP = ConvertRSAParametersField(privKey.DP, rp.P.Length);
+        rp.DQ = ConvertRSAParametersField(privKey.DQ, rp.Q.Length);
+        rp.InverseQ = ConvertRSAParametersField(privKey.QInv, rp.Q.Length);
+
+        return rp;
+    }
+
+    private static byte[] ConvertRSAParametersField(BigInteger n, int size)
+    {
+        byte[] bs = n.ToByteArrayUnsigned();
+        if (bs.Length == size)
+            return bs;
+        if (bs.Length > size)
+            throw new ArgumentException("Specified size too small", "size");
+        byte[] padded = new byte[size];
+        Array.Copy(bs, 0, padded, size - bs.Length, bs.Length);
+        return padded;
+    }
+
+}