使用 RSA AES 提供程序生成自签名 1024 位 X509Certificate2 时出现问题

Question

我正在尝试使用 Microsoft AES Cryptographic Provider:

生成一个 X509Certificate2 对象

CALG_AES_256 (0x00006610) 256 bit AES. This algorithm is supported by the Microsoft AES Cryptographic Provider.

我的问题是我对 CryptGenKey(providerContext, 0x6610, 0x4000001, out cryptKey) 的调用失败并出现以下错误：

An unhandled exception of type 'System.Runtime.InteropServices.COMException' occurred in mscorlib.dll

Additional information: Invalid flags specified. (Exception from HRESULT: 0x80090009)

我使用的标志是 (1024 << 16) | 1)。除非我弄错了，否则这不应该产生一个 1024 位的可导出密钥 according to the documentation on MSDN 吗？我这里的方法有什么问题？

我的代码如下：

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;
        }
    }
}

要调用它，您可以使用：X509Certificate2Helper.GenerateSelfSignedCertificate("CN = Example");.

更新:

如果我使用 0x1 作为标志：

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

它超过了 CryptGenKey，但随后在 CertCreateSelfSignCertificate 上失败了：

An unhandled exception of type 'System.Runtime.InteropServices.COMException' occurred in mscorlib.dll

Additional information: Key does not exist. (Exception from HRESULT: 0x8009000D)

必须以不同方式传入此键集吗？我上面创建它的方式有什么问题？

Answer 1

使用这个公式

(keySize * 65536) | 1;

对于 2048 位密钥，它是 0x08000001。根据 CryptGenKey 方法的文档，您可以使用 RSA1024BIT_KEY 生成 1024 位密钥。我尝试寻找定义并找到 this（尽管它在 Adobe 网站上:)）

#define RSA1024BIT_KEY                   0x04000000

Answer 2

问题出在 CryptGenKey 函数调用上。在 Algid 参数中，您应该传递 0x1（用于 RSA 密钥交换）或 0x2（RSA 数字签名）。您不需要其他值。密钥长度值应为 0x4000001（具有可导出密钥）。此外，我注意到您在实例化 CryptKeyProviderInformation 对象时传递了不正确的提供程序类型。替换此行：

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

这一行：

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

使用 RSA AES 提供程序生成自签名 1024 位 X509Certificate2 时出现问题

Problems generating a self-signed 1024-bit X509Certificate2 using the RSA AES provider

.net

c#

encryption

ssl

x509certificate2