使用RSA AES提供程序生成自簽名1024位X509Certificate2時出現問題

Question

我正在嘗試使用Microsoft AES加密提供程序生成X509Certificate2對象：

CALG_AES_256（0x00006610）256位AES。 Microsoft AES加密提供程序支持此算法。

我的問題是我對CryptGenKey(providerContext, 0x6610, 0x4000001, out cryptKey)失敗，出現以下錯誤：

mscorlib.dll中發生未處理的“System.Runtime.InteropServices.COMException”類型異常

附加信息：指定了無效標志。 （HRESULT異常：0x80090009）

我使用的標志是(1024 << 16) | 1) (1024 << 16) | 1) 。 除非我弄錯了， 根據MSDN上的文檔 ，這不應該產生1024位可導出密鑰嗎？ 我的方法有什么問題？

我的代碼如下：

using System;
using System.Security;
using System.Runtime.InteropServices;
using System.Runtime.CompilerServices;
using System.Security.Cryptography.X509Certificates;

namespace WebSockets
{
    public struct SystemTime
    {
        public short Year;
        public short Month;
        public short DayOfWeek;
        public short Day;
        public short Hour;
        public short Minute;
        public short Second;
        public short Milliseconds;
    }

    public static class MarshalHelper
    {
        public static void CheckReturnValue(bool nativeCallSucceeded)
        {
            if (!nativeCallSucceeded)
                Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
        }
    }

    public static class DateTimeExtensions
    {

        [DllImport("kernel32.dll", SetLastError = true)]
        static extern bool FileTimeToSystemTime(ref long fileTime, out SystemTime systemTime);

        public static SystemTime ToSystemTime(this DateTime dateTime)
        {
            long fileTime = dateTime.ToFileTime();
            SystemTime systemTime;
            MarshalHelper.CheckReturnValue(FileTimeToSystemTime(ref fileTime, out systemTime));
            return systemTime;
        }
    }

    class X509Certificate2Helper
    {

        [DllImport("advapi32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
        static extern bool CryptAcquireContextW(out IntPtr providerContext, string container, string provider, uint providerType, uint flags);

        [DllImport("advapi32.dll", SetLastError = true)]
        static extern bool CryptReleaseContext(IntPtr providerContext, int flags);

        [DllImport("advapi32.dll", SetLastError = true)]
        static extern bool CryptGenKey(IntPtr providerContext, int algorithmId, int flags, out IntPtr cryptKeyHandle);

        [DllImport("advapi32.dll", SetLastError = true)]
        static extern bool CryptDestroyKey(IntPtr cryptKeyHandle);

        [DllImport("crypt32.dll", SetLastError = true)]
        static extern bool CertStrToNameW(int certificateEncodingType, IntPtr x500, int strType, IntPtr reserved, byte[] encoded, ref int encodedLength, out IntPtr errorString);

        [DllImport("crypt32.dll", SetLastError = true)]
        static extern IntPtr CertCreateSelfSignCertificate(IntPtr providerHandle, ref CryptoApiBlob subjectIssuerBlob, int flags, ref CryptKeyProviderInformation keyProviderInformation, IntPtr signatureAlgorithm, ref SystemTime startTime, ref SystemTime endTime, IntPtr extensions);

        [DllImport("crypt32.dll", SetLastError = true)]
        static extern bool CertFreeCertificateContext(IntPtr certificateContext);

        [DllImport("crypt32.dll", SetLastError = true)]
        static extern bool CertSetCertificateContextProperty(IntPtr certificateContext, int propertyId, int flags, ref CryptKeyProviderInformation data);

        public static X509Certificate2 GenerateSelfSignedCertificate(String name = "", DateTime? startTime = null, DateTime? endTime = null)
        {
            if (startTime == null || (DateTime)startTime < DateTime.FromFileTimeUtc(0))
                startTime = DateTime.FromFileTimeUtc(0);
            var startSystemTime = ((DateTime)startTime).ToSystemTime();
            if (endTime == null)
                endTime = DateTime.MaxValue;
            var endSystemTime = ((DateTime)endTime).ToSystemTime();
            string containerName = Guid.NewGuid().ToString();
            GCHandle dataHandle = new GCHandle();
            IntPtr providerContext = IntPtr.Zero;
            IntPtr cryptKey = IntPtr.Zero;
            IntPtr certificateContext = IntPtr.Zero;
            IntPtr algorithmPointer = IntPtr.Zero;
            RuntimeHelpers.PrepareConstrainedRegions();
            try
            {
                MarshalHelper.CheckReturnValue(CryptAcquireContextW(out providerContext, containerName, null, 0x18, 0x8));
                MarshalHelper.CheckReturnValue(CryptGenKey(providerContext, 0x6610, 0x4000001, out cryptKey));
                IntPtr errorStringPtr;
                int nameDataLength = 0;
                byte[] nameData;
                dataHandle = GCHandle.Alloc(name, GCHandleType.Pinned);
                if (!CertStrToNameW(0x10001, dataHandle.AddrOfPinnedObject(), 3, IntPtr.Zero, null, ref nameDataLength, out errorStringPtr))
                {
                    string error = Marshal.PtrToStringUni(errorStringPtr);
                    throw new ArgumentException(error);
                }
                nameData = new byte[nameDataLength];
                if (!CertStrToNameW(0x10001, dataHandle.AddrOfPinnedObject(), 3, IntPtr.Zero, nameData, ref nameDataLength, out errorStringPtr))
                {
                    string error = Marshal.PtrToStringUni(errorStringPtr);
                    throw new ArgumentException(error);
                }
                dataHandle.Free();
                dataHandle = GCHandle.Alloc(nameData, GCHandleType.Pinned);
                CryptoApiBlob nameBlob = new CryptoApiBlob { cbData = (uint)nameData.Length, pbData = dataHandle.AddrOfPinnedObject() };
                dataHandle.Free();
                CryptKeyProviderInformation keyProvider = new CryptKeyProviderInformation { pwszContainerName = containerName, dwProvType = 1, dwKeySpec = 1 };
                CryptAlgorithmIdentifier algorithm = new CryptAlgorithmIdentifier { pszObjId = "1.2.840.113549.1.1.13", Parameters = new CryptoApiBlob() };
                algorithmPointer = Marshal.AllocHGlobal(Marshal.SizeOf(algorithm));
                Marshal.StructureToPtr(algorithm, algorithmPointer, false);
                certificateContext = CertCreateSelfSignCertificate(providerContext, ref nameBlob, 0, ref keyProvider, algorithmPointer, ref startSystemTime, ref endSystemTime, IntPtr.Zero);
                MarshalHelper.CheckReturnValue(certificateContext != IntPtr.Zero);
                return new X509Certificate2(certificateContext);
            }
            finally
            {
                if (dataHandle.IsAllocated)
                    dataHandle.Free();
                if (certificateContext != IntPtr.Zero)
                    CertFreeCertificateContext(certificateContext);
                if (cryptKey != IntPtr.Zero)
                    CryptDestroyKey(cryptKey);
                if (providerContext != IntPtr.Zero)
                    CryptReleaseContext(providerContext, 0);
                if (algorithmPointer != IntPtr.Zero)
                {
                    Marshal.DestroyStructure(algorithmPointer, typeof(CryptAlgorithmIdentifier));
                    Marshal.FreeHGlobal(algorithmPointer);
                }
            }
        }

        struct CryptoApiBlob
        {
            public uint cbData;
            public IntPtr pbData;
        }

        struct CryptAlgorithmIdentifier {
            [MarshalAs(UnmanagedType.LPStr)]
            public String pszObjId;
            public CryptoApiBlob Parameters;
        }

        struct CryptKeyProviderInformation
        {
            [MarshalAs(UnmanagedType.LPWStr)]
            public String pwszContainerName;
            [MarshalAs(UnmanagedType.LPWStr)]
            public String pwszProvName;
            public uint dwProvType;
            public uint dwFlags;
            public uint cProvParam;
            public IntPtr rgProvParam;
            public uint dwKeySpec;
        }
    }
}

要調用它，您可以使用： X509Certificate2Helper.GenerateSelfSignedCertificate("CN = Example"); 。

更新 ：

如果我使用0x1作為標志：

CryptAcquireContextW(out providerContext, containerName, "Microsoft Enhanced RSA and AES Cryptographic Provider", 0x18, 0x8);
CryptGenKey(providerContext, 0x6610, 0x1, out cryptKey);

它越過CryptGenKey ，但隨后在CertCreateSelfSignCertificate上失敗：

mscorlib.dll中發生未處理的“System.Runtime.InteropServices.COMException”類型異常

附加信息：密鑰不存在。 （HRESULT異常：0x8009000D）

這個鍵集必須以不同方式傳遞嗎？ 我在上面創建它的方式有什么問題？

Answer 1

問題出在CryptGenKey函數調用上。 在Algid參數中，您應該傳遞0x1（用於RSA密鑰交換）或0x2（RSA數字簽名）。 您不需要其他值。 密鑰長度值應為0x4000001（帶可導出密鑰）。 另外，我注意到在實例化CryptKeyProviderInformation對象時傳遞了錯誤的提供程序類型。 替換此行：

CryptKeyProviderInformation keyProvider = new CryptKeyProviderInformation {
    pwszContainerName = containerName,
    dwProvType = 1,
    dwKeySpec = 1
};

用這一行：

CryptKeyProviderInformation keyProvider = new CryptKeyProviderInformation {
    pwszContainerName = containerName,
    dwProvType = 0x18,
    dwKeySpec = 1
};

Answer 2

使用此公式

(keySize * 65536) | 1;

對於2048位密鑰，它是0x08000001。 根據CryptGenKey方法的文檔，您可以使用RSA1024BIT_KEY生成1024位密鑰。 我已經嘗試尋找定義並找到了這個 （雖然它是在Adobe網站上:)）

#define RSA1024BIT_KEY                   0x04000000