Interop.cs

Go to the documentation of this file.

using System;
using System.Runtime.InteropServices;
using System.Security.Cryptography;
 
internal static class Interop
{
    internal static class Crypt32
    {
        internal struct CRYPT_OID_INFO
        {
            public int cbSize;
 
            public IntPtr pszOID;
 
            public IntPtr pwszName;
 
            public OidGroup dwGroupId;
 
            public int AlgId;
 
            public int cbData;
 
            public IntPtr pbData;
 
            public string OID => Marshal.PtrToStringAnsi(pszOID);
 
            public string Name => Marshal.PtrToStringUni(pwszName);
        }
 
        internal enum CryptOidInfoKeyType
        {
            CRYPT_OID_INFO_OID_KEY = 1,
            CRYPT_OID_INFO_NAME_KEY,
            CRYPT_OID_INFO_ALGID_KEY,
            CRYPT_OID_INFO_SIGN_KEY,
            CRYPT_OID_INFO_CNG_ALGID_KEY,
            CRYPT_OID_INFO_CNG_SIGN_KEY
        }
        internal enum CryptOidInfoKeyType {…};
 
        [DllImport("crypt32.dll", BestFitMapping = false, SetLastError = true)]
        internal unsafe static extern bool CryptFormatObject([In] int dwCertEncodingType, [In] int dwFormatType, [In] int dwFormatStrType, [In] IntPtr pFormatStruct, [In] byte* lpszStructType, [In] byte[] pbEncoded, [In] int cbEncoded, [Out] void* pbFormat, [In][Out] ref int pcbFormat);
 
        internal static CRYPT_OID_INFO FindOidInfo(CryptOidInfoKeyType keyType, string key, OidGroup group, bool fallBackToAllGroups)
        {
            IntPtr intPtr = IntPtr.Zero;
            try
            {
                intPtr = keyType switch
                {
                    CryptOidInfoKeyType.CRYPT_OID_INFO_OID_KEY => Marshal.StringToCoTaskMemAnsi(key), 
                    CryptOidInfoKeyType.CRYPT_OID_INFO_NAME_KEY => Marshal.StringToCoTaskMemUni(key), 
                    _ => throw new NotSupportedException(), 
                };
                if (!OidGroupWillNotUseActiveDirectory(group))
                {
                    OidGroup group2 = group | (OidGroup)(-2147483648);
                    IntPtr intPtr2 = CryptFindOIDInfo(keyType, intPtr, group2);
                    if (intPtr2 != IntPtr.Zero)
                    {
                        return Marshal.PtrToStructure<CRYPT_OID_INFO>(intPtr2);
                    }
                }
                IntPtr intPtr3 = CryptFindOIDInfo(keyType, intPtr, group);
                if (intPtr3 != IntPtr.Zero)
                {
                    return Marshal.PtrToStructure<CRYPT_OID_INFO>(intPtr3);
                }
                if (fallBackToAllGroups && group != 0)
                {
                    IntPtr intPtr4 = CryptFindOIDInfo(keyType, intPtr, OidGroup.All);
                    if (intPtr4 != IntPtr.Zero)
                    {
                        return Marshal.PtrToStructure<CRYPT_OID_INFO>(intPtr4);
                    }
                }
                CRYPT_OID_INFO result = default(CRYPT_OID_INFO);
                result.AlgId = -1;
                return result;
            }
            finally
            {
                if (intPtr != IntPtr.Zero)
                {
                    Marshal.FreeCoTaskMem(intPtr);
                }
            }
        }
        internal static CRYPT_OID_INFO FindOidInfo(CryptOidInfoKeyType keyType, string key, OidGroup group, bool fallBackToAllGroups) {…}
 
        private static bool OidGroupWillNotUseActiveDirectory(OidGroup group)
        {
            if (group != OidGroup.HashAlgorithm && group != OidGroup.EncryptionAlgorithm && group != OidGroup.PublicKeyAlgorithm && group != OidGroup.SignatureAlgorithm && group != OidGroup.Attribute && group != OidGroup.ExtensionOrAttribute)
            {
                return group == OidGroup.KeyDerivationFunction;
            }
            return true;
        }
        private static bool OidGroupWillNotUseActiveDirectory(OidGroup group) {…}
 
        [DllImport("crypt32.dll", CharSet = CharSet.Unicode)]
        private static extern IntPtr CryptFindOIDInfo(CryptOidInfoKeyType dwKeyType, IntPtr pvKey, OidGroup group);
    }
}