Obtenez timestamp à partir des fichiers signés Authenticode in.NET

retour à la question originale, Je n'ai pas pu trouver managed way donc fini par utiliser pInvoke comme suit:

public static bool IsTimestamped(string filename)
{
    try
    {
        int encodingType;
        int contentType;
        int formatType;
        IntPtr certStore = IntPtr.Zero;
        IntPtr cryptMsg = IntPtr.Zero;
        IntPtr context = IntPtr.Zero;

        if (!WinCrypt.CryptQueryObject(
            WinCrypt.CERT_QUERY_OBJECT_FILE,
            Marshal.StringToHGlobalUni(filename),
            WinCrypt.CERT_QUERY_CONTENT_FLAG_ALL,
            WinCrypt.CERT_QUERY_FORMAT_FLAG_ALL,
            0,
            out encodingType,
            out contentType,
            out formatType,
            ref certStore,
            ref cryptMsg,
            ref context))
        {
            throw new Win32Exception(Marshal.GetLastWin32Error());
        }

        //expecting contentType=10; CERT_QUERY_CONTENT_PKCS7_SIGNED_EMBED 
        //Logger.LogInfo(string.Format("Querying file '{0}':", filename));
        //Logger.LogInfo(string.Format("  Encoding Type: {0}", encodingType));
        //Logger.LogInfo(string.Format("  Content Type: {0}", contentType));
        //Logger.LogInfo(string.Format("  Format Type: {0}", formatType));
        //Logger.LogInfo(string.Format("  Cert Store: {0}", certStore.ToInt32()));
        //Logger.LogInfo(string.Format("  Crypt Msg: {0}", cryptMsg.ToInt32()));
        //Logger.LogInfo(string.Format("  Context: {0}", context.ToInt32()));


        // Get size of the encoded message.
        int cbData = 0;
        if (!WinCrypt.CryptMsgGetParam(
            cryptMsg,
            WinCrypt.CMSG_ENCODED_MESSAGE,//Crypt32.CMSG_SIGNER_INFO_PARAM,
            0,
            IntPtr.Zero,
            ref cbData))
        {
            throw new Win32Exception(Marshal.GetLastWin32Error());
        }

        var vData = new byte[cbData];

        // Get the encoded message.
        if (!WinCrypt.CryptMsgGetParam(
            cryptMsg,
            WinCrypt.CMSG_ENCODED_MESSAGE,//Crypt32.CMSG_SIGNER_INFO_PARAM,
            0,
            vData,
            ref cbData))
        {
            throw new Win32Exception(Marshal.GetLastWin32Error());
        }

        var signedCms = new SignedCms();
        signedCms.Decode(vData);

        foreach (var signerInfo in signedCms.SignerInfos)
        {
            foreach (var unsignedAttribute in signerInfo.UnsignedAttributes)
            {
                if (unsignedAttribute.Oid.Value == WinCrypt.szOID_RSA_counterSign)
                {
                    //Note at this point we assume this counter signature is the timestamp
                    //refer to http://support.microsoft.com/kb/323809 for the origins

                    //TODO: extract timestamp value, if required
                    return true;
                }

            }
        }
    }
    catch (Exception)
    {
        // no logging
    }

    return false;
}

et la WinCrypt.cs contient le code suivant:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;

namespace MyNamespace.Win32
{
    static class WinCrypt
    {
        [StructLayout(LayoutKind.Sequential)]
        public struct BLOB
        {
            public int cbData;
            public IntPtr pbData;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct CRYPT_ALGORITHM_IDENTIFIER
        {
            public String pszObjId;
            BLOB Parameters;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct CERT_ID
        {
            public int dwIdChoice;
            public BLOB IssuerSerialNumberOrKeyIdOrHashId;
        }

        [StructLayoutAttribute(LayoutKind.Sequential)]
        public struct SIGNER_SUBJECT_INFO
        {
            /// DWORD->unsigned int
            public uint cbSize;

            /// DWORD*
            public System.IntPtr pdwIndex;

            /// DWORD->unsigned int
            public uint dwSubjectChoice;

            /// SubjectChoiceUnion
            public SubjectChoiceUnion Union1;
        }

        [StructLayoutAttribute(LayoutKind.Explicit)]
        public struct SubjectChoiceUnion
        {

            /// SIGNER_FILE_INFO*
            [FieldOffsetAttribute(0)]
            public System.IntPtr pSignerFileInfo;

            /// SIGNER_BLOB_INFO*
            [FieldOffsetAttribute(0)]
            public System.IntPtr pSignerBlobInfo;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct CERT_NAME_BLOB
        {
            public uint cbData;
            [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 0)]
            public byte[] pbData;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct CRYPT_INTEGER_BLOB
        {
            public UInt32 cbData;
            public IntPtr pbData;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct CRYPT_ATTR_BLOB
        {
            public uint cbData;
            [MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 0)]
            public byte[] pbData;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct CRYPT_ATTRIBUTE
        {
            [MarshalAs(UnmanagedType.LPStr)]
            public string pszObjId;
            public uint cValue;
            [MarshalAs(UnmanagedType.LPStruct)]
            public CRYPT_ATTR_BLOB rgValue;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct CMSG_SIGNER_INFO
        {
            public int dwVersion;
            private CERT_NAME_BLOB Issuer;
            CRYPT_INTEGER_BLOB SerialNumber;
            CRYPT_ALGORITHM_IDENTIFIER HashAlgorithm;
            CRYPT_ALGORITHM_IDENTIFIER HashEncryptionAlgorithm;
            BLOB EncryptedHash;
            CRYPT_ATTRIBUTE[] AuthAttrs;
            CRYPT_ATTRIBUTE[] UnauthAttrs;
        }

        [DllImport("crypt32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        public static extern Boolean CryptQueryObject(
            int dwObjectType,
            IntPtr pvObject,
            int dwExpectedContentTypeFlags,
            int dwExpectedFormatTypeFlags,
            int dwFlags,
            out int pdwMsgAndCertEncodingType,
            out int pdwContentType,
            out int pdwFormatType,
            ref IntPtr phCertStore,
            ref IntPtr phMsg,
            ref IntPtr ppvContext);


        [DllImport("crypt32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        public static extern Boolean CryptMsgGetParam(
            IntPtr hCryptMsg,
            int dwParamType,
            int dwIndex,
            IntPtr pvData,
            ref int pcbData
        );

        [DllImport("crypt32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        public static extern Boolean CryptMsgGetParam(
            IntPtr hCryptMsg,
            int dwParamType,
            int dwIndex,
            [In, Out] byte[] vData,
            ref int pcbData
        );

        [DllImport("crypt32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool CryptDecodeObject(
          uint CertEncodingType,
          UIntPtr lpszStructType,
          byte[] pbEncoded,
          uint cbEncoded,
          uint flags,
          [In, Out] byte[] pvStructInfo,
          ref uint cbStructInfo);


        public const int CRYPT_ASN_ENCODING = 0x00000001;
        public const int CRYPT_NDR_ENCODING = 0x00000002;
        public const int X509_ASN_ENCODING = 0x00000001;
        public const int X509_NDR_ENCODING = 0x00000002;
        public const int PKCS_7_ASN_ENCODING = 0x00010000;
        public const int PKCS_7_NDR_ENCODING = 0x00020000;

        public static UIntPtr PKCS7_SIGNER_INFO = new UIntPtr(500);
        public static UIntPtr CMS_SIGNER_INFO = new UIntPtr(501);

        public static string szOID_RSA_signingTime = "1.2.840.113549.1.9.5";
        public static string szOID_RSA_counterSign = "1.2.840.113549.1.9.6";

        //+-------------------------------------------------------------------------
        //  Get parameter types and their corresponding data structure definitions.
        //--------------------------------------------------------------------------
        public const int CMSG_TYPE_PARAM = 1;
        public const int CMSG_CONTENT_PARAM = 2;
        public const int CMSG_BARE_CONTENT_PARAM = 3;
        public const int CMSG_INNER_CONTENT_TYPE_PARAM = 4;
        public const int CMSG_SIGNER_COUNT_PARAM = 5;
        public const int CMSG_SIGNER_INFO_PARAM = 6;
        public const int CMSG_SIGNER_CERT_INFO_PARAM = 7;
        public const int CMSG_SIGNER_HASH_ALGORITHM_PARAM = 8;
        public const int CMSG_SIGNER_AUTH_ATTR_PARAM = 9;
        public const int CMSG_SIGNER_UNAUTH_ATTR_PARAM = 10;
        public const int CMSG_CERT_COUNT_PARAM = 11;
        public const int CMSG_CERT_PARAM = 12;
        public const int CMSG_CRL_COUNT_PARAM = 13;
        public const int CMSG_CRL_PARAM = 14;
        public const int CMSG_ENVELOPE_ALGORITHM_PARAM = 15;
        public const int CMSG_RECIPIENT_COUNT_PARAM = 17;
        public const int CMSG_RECIPIENT_INDEX_PARAM = 18;
        public const int CMSG_RECIPIENT_INFO_PARAM = 19;
        public const int CMSG_HASH_ALGORITHM_PARAM = 20;
        public const int CMSG_HASH_DATA_PARAM = 21;
        public const int CMSG_COMPUTED_HASH_PARAM = 22;
        public const int CMSG_ENCRYPT_PARAM = 26;
        public const int CMSG_ENCRYPTED_DIGEST = 27;
        public const int CMSG_ENCODED_SIGNER = 28;
        public const int CMSG_ENCODED_MESSAGE = 29;
        public const int CMSG_VERSION_PARAM = 30;
        public const int CMSG_ATTR_CERT_COUNT_PARAM = 31;
        public const int CMSG_ATTR_CERT_PARAM = 32;
        public const int CMSG_CMS_RECIPIENT_COUNT_PARAM = 33;
        public const int CMSG_CMS_RECIPIENT_INDEX_PARAM = 34;
        public const int CMSG_CMS_RECIPIENT_ENCRYPTED_KEY_INDEX_PARAM = 35;
        public const int CMSG_CMS_RECIPIENT_INFO_PARAM = 36;
        public const int CMSG_UNPROTECTED_ATTR_PARAM = 37;
        public const int CMSG_SIGNER_CERT_ID_PARAM = 38;
        public const int CMSG_CMS_SIGNER_INFO_PARAM = 39;


        //-------------------------------------------------------------------------
        //dwObjectType for CryptQueryObject
        //-------------------------------------------------------------------------
        public const int CERT_QUERY_OBJECT_FILE = 0x00000001;
        public const int CERT_QUERY_OBJECT_BLOB = 0x00000002;

        //-------------------------------------------------------------------------
        //dwContentType for CryptQueryObject
        //-------------------------------------------------------------------------
        //encoded single certificate
        public const int CERT_QUERY_CONTENT_CERT = 1;
        //encoded single CTL
        public const int CERT_QUERY_CONTENT_CTL = 2;
        //encoded single CRL
        public const int CERT_QUERY_CONTENT_CRL = 3;
        //serialized store
        public const int CERT_QUERY_CONTENT_SERIALIZED_STORE = 4;
        //serialized single certificate
        public const int CERT_QUERY_CONTENT_SERIALIZED_CERT = 5;
        //serialized single CTL
        public const int CERT_QUERY_CONTENT_SERIALIZED_CTL = 6;
        //serialized single CRL
        public const int CERT_QUERY_CONTENT_SERIALIZED_CRL = 7;
        //a PKCS#7 signed message
        public const int CERT_QUERY_CONTENT_PKCS7_SIGNED = 8;
        //a PKCS#7 message, such as enveloped message.  But it is not a signed message,
        public const int CERT_QUERY_CONTENT_PKCS7_UNSIGNED = 9;
        //a PKCS7 signed message embedded in a file
        public const int CERT_QUERY_CONTENT_PKCS7_SIGNED_EMBED = 10;
        //an encoded PKCS#10
        public const int CERT_QUERY_CONTENT_PKCS10 = 11;
        //an encoded PKX BLOB
        public const int CERT_QUERY_CONTENT_PFX = 12;
        //an encoded CertificatePair (contains forward and/or reverse cross certs)
        public const int CERT_QUERY_CONTENT_CERT_PAIR = 13;

        //-------------------------------------------------------------------------
        //dwExpectedConentTypeFlags for CryptQueryObject
        //-------------------------------------------------------------------------
        //encoded single certificate
        public const int CERT_QUERY_CONTENT_FLAG_CERT = (1 << CERT_QUERY_CONTENT_CERT);

        //encoded single CTL
        public const int CERT_QUERY_CONTENT_FLAG_CTL = (1 << CERT_QUERY_CONTENT_CTL);

        //encoded single CRL
        public const int CERT_QUERY_CONTENT_FLAG_CRL = (1 << CERT_QUERY_CONTENT_CRL);

        //serialized store
        public const int CERT_QUERY_CONTENT_FLAG_SERIALIZED_STORE = (1 << CERT_QUERY_CONTENT_SERIALIZED_STORE);

        //serialized single certificate
        public const int CERT_QUERY_CONTENT_FLAG_SERIALIZED_CERT = (1 << CERT_QUERY_CONTENT_SERIALIZED_CERT);

        //serialized single CTL
        public const int CERT_QUERY_CONTENT_FLAG_SERIALIZED_CTL = (1 << CERT_QUERY_CONTENT_SERIALIZED_CTL);

        //serialized single CRL
        public const int CERT_QUERY_CONTENT_FLAG_SERIALIZED_CRL = (1 << CERT_QUERY_CONTENT_SERIALIZED_CRL);

        //an encoded PKCS#7 signed message
        public const int CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED = (1 << CERT_QUERY_CONTENT_PKCS7_SIGNED);

        //an encoded PKCS#7 message.  But it is not a signed message
        public const int CERT_QUERY_CONTENT_FLAG_PKCS7_UNSIGNED = (1 << CERT_QUERY_CONTENT_PKCS7_UNSIGNED);

        //the content includes an embedded PKCS7 signed message
        public const int CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED_EMBED = (1 << CERT_QUERY_CONTENT_PKCS7_SIGNED_EMBED);

        //an encoded PKCS#10
        public const int CERT_QUERY_CONTENT_FLAG_PKCS10 = (1 << CERT_QUERY_CONTENT_PKCS10);

        //an encoded PFX BLOB
        public const int CERT_QUERY_CONTENT_FLAG_PFX = (1 << CERT_QUERY_CONTENT_PFX);

        //an encoded CertificatePair (contains forward and/or reverse cross certs)
        public const int CERT_QUERY_CONTENT_FLAG_CERT_PAIR = (1 << CERT_QUERY_CONTENT_CERT_PAIR);

        //content can be any type
        public const int CERT_QUERY_CONTENT_FLAG_ALL =
            CERT_QUERY_CONTENT_FLAG_CERT |
            CERT_QUERY_CONTENT_FLAG_CTL |
            CERT_QUERY_CONTENT_FLAG_CRL |
            CERT_QUERY_CONTENT_FLAG_SERIALIZED_STORE |
            CERT_QUERY_CONTENT_FLAG_SERIALIZED_CERT |
            CERT_QUERY_CONTENT_FLAG_SERIALIZED_CTL |
            CERT_QUERY_CONTENT_FLAG_SERIALIZED_CRL |
            CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED |
            CERT_QUERY_CONTENT_FLAG_PKCS7_UNSIGNED |
            CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED_EMBED |
            CERT_QUERY_CONTENT_FLAG_PKCS10 |
            CERT_QUERY_CONTENT_FLAG_PFX |
            CERT_QUERY_CONTENT_FLAG_CERT_PAIR;

        //-------------------------------------------------------------------------
        //dwFormatType for CryptQueryObject
        //-------------------------------------------------------------------------
        //the content is in binary format
        public const int CERT_QUERY_FORMAT_BINARY = 1;

        //the content is base64 encoded
        public const int CERT_QUERY_FORMAT_BASE64_ENCODED = 2;

        //the content is ascii hex encoded with "{ASN}" prefix
        public const int CERT_QUERY_FORMAT_ASN_ASCII_HEX_ENCODED = 3;

        //-------------------------------------------------------------------------
        //dwExpectedFormatTypeFlags for CryptQueryObject
        //-------------------------------------------------------------------------
        //the content is in binary format
        public const int CERT_QUERY_FORMAT_FLAG_BINARY = (1 << CERT_QUERY_FORMAT_BINARY);

        //the content is base64 encoded
        public const int CERT_QUERY_FORMAT_FLAG_BASE64_ENCODED = (1 << CERT_QUERY_FORMAT_BASE64_ENCODED);

        //the content is ascii hex encoded with "{ASN}" prefix
        public const int CERT_QUERY_FORMAT_FLAG_ASN_ASCII_HEX_ENCODED = (1 << CERT_QUERY_FORMAT_ASN_ASCII_HEX_ENCODED);

        //the content can be of any format
        public const int CERT_QUERY_FORMAT_FLAG_ALL =
            CERT_QUERY_FORMAT_FLAG_BINARY |
            CERT_QUERY_FORMAT_FLAG_BASE64_ENCODED |
            CERT_QUERY_FORMAT_FLAG_ASN_ASCII_HEX_ENCODED;

    }
}

Merci les gars,

- Vous m'aider beaucoup :)

BTW: j'ai trouvé une façon plus simple d'obtenir l'horodatage.

la voici:

foreach (var signerInfo in signedCms.SignerInfos)
{
  foreach (var unsignedAttribute in signerInfo.UnsignedAttributes)
  {
    if (unsignedAttribute.Oid.Value == WinCrypt.szOID_RSA_counterSign)
    {
      foreach (var counterSignInfo in signerInfo.CounterSignerInfos)
      {
        foreach (var signedAttribute in counterSignInfo.SignedAttributes)
        {
          if (signedAttribute.Oid.Value == WinCrypt.szOID_RSA_signingTime)
          {
            Pkcs9SigningTime signingTime = (Pkcs9SigningTime)signedAttribute.Values[0];
            Console.Out.WriteLine("Signing Time UTC: " + signingTime.SigningTime);
          }
        }
      }
      return true;
    }
  }
}

Merci à l'OP pour votre travail. J'ai ajouté la mise en œuvre pour obtenir le TimeStamp réel du cert.

foreach (var signerInfo in signedCms.SignerInfos)
            {
                foreach (var unsignedAttribute in signerInfo.UnsignedAttributes)
                {
                    if (unsignedAttribute.Oid.Value == WinCrypt.szOID_RSA_counterSign)
                    {
                        foreach (var counterSignInfo in signerInfo.CounterSignerInfos)
                        {
                            foreach (var signedAttribute in counterSignInfo.SignedAttributes)
                            {
                                if (signedAttribute.Oid.Value == WinCrypt.szOID_RSA_signingTime)
                                {                                        
                                    System.Runtime.InteropServices.ComTypes.FILETIME fileTime = new System.Runtime.InteropServices.ComTypes.FILETIME();
                                    int fileTimeSize = Marshal.SizeOf(fileTime);
                                    IntPtr fileTimePtr = Marshal.AllocCoTaskMem(fileTimeSize);
                                    Marshal.StructureToPtr(fileTime, fileTimePtr, true);

                                    byte[] buffdata = new byte[fileTimeSize];
                                    Marshal.Copy(fileTimePtr, buffdata, 0, fileTimeSize);

                                    uint buffSize = (uint)buffdata.Length;

                                    uint encoding = WinCrypt.X509_ASN_ENCODING | WinCrypt.PKCS_7_ASN_ENCODING;

                                    UIntPtr rsaSigningTime = (UIntPtr)(uint)Marshal.StringToHGlobalAnsi(WinCrypt.szOID_RSA_signingTime);

                                    byte[] pbData = signedAttribute.Values[0].RawData;                                         
                                    uint ucbData = (uint)pbData.Length;

                                    bool workie = WinCrypt.CryptDecodeObject(encoding, rsaSigningTime.ToUInt32(), pbData, ucbData, 0, buffdata, ref buffSize);

                                    if (workie)
                                    {
                                        IntPtr fileTimePtr2 = Marshal.AllocCoTaskMem(buffdata.Length);
                                        Marshal.Copy(buffdata, 0, fileTimePtr2, buffdata.Length);
                                        System.Runtime.InteropServices.ComTypes.FILETIME fileTime2 = (System.Runtime.InteropServices.ComTypes.FILETIME)Marshal.PtrToStructure(fileTimePtr2, typeof(System.Runtime.InteropServices.ComTypes.FILETIME));

                                        long hFT2 = (((long)fileTime2.dwHighDateTime) << 32) + ((uint)fileTime2.dwLowDateTime);

                                        DateTime dte = DateTime.FromFileTime(hFT2);
                                        Console.WriteLine(dte.ToString());
                                    }
                                    else
                                    {
                                        throw new Win32Exception(Marshal.GetLastWin32Error());                                            
                                    }

                                }    
                            }

                        }                            

                        return true;
                    }

                }
            }

je voulais enlever le sujet du certificat numérique, c'est une chaîne de caractères comme

• CN=Microsoft Corporation, OU= MOPR, O= Microsoft Corporation, L= Redmond, S=Washington, C = US

j'ai trouvé le X509Certificate vraiment lent et charge le fichier entier dans la mémoire. J'ai essayé de lire un fichier de correctifs de 800 Mo et ma mémoire a augmenté de 800 Mo pendant qu'il le lisait, et il a fallu plus de 30 secondes!!

je me suis tenu sur les relents des affiches ci-dessus an a réussi à modifier le code ci-dessus pour obtenir un objet X509Certificate2 des centaines de fois plus rapidement qu'en utilisant L'objet X509.

Merci de lire mon blog pour plus de détails, avec des images de la performance des différences. X509Certificate objet c# de la performance et des problèmes de mémoire alternative – fixe

essaye ceci:

public static X509Certificate2 GetDigitalCertificate(string filename)
    {
        X509Certificate2 cert = null;

        int encodingType;
        int contentType;
        int formatType;
        IntPtr certStore = IntPtr.Zero;
        IntPtr cryptMsg = IntPtr.Zero;
        IntPtr context = IntPtr.Zero;

        if (!WinCrypt.CryptQueryObject(
            WinCrypt.CERT_QUERY_OBJECT_FILE,
            Marshal.StringToHGlobalUni(filename),
            (WinCrypt.CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED
            | WinCrypt.CERT_QUERY_CONTENT_FLAG_PKCS7_UNSIGNED
            | WinCrypt.CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED_EMBED), // <-- These are the attributes that makes it fast!!
            WinCrypt.CERT_QUERY_FORMAT_FLAG_ALL,
            0,
            out encodingType,
            out contentType,
            out formatType,
            ref certStore,
            ref cryptMsg,
            ref context))
        {
            throw new Win32Exception(Marshal.GetLastWin32Error());
        }

        // Get size of the encoded message.
        int cbData = 0;
        if (!WinCrypt.CryptMsgGetParam(
            cryptMsg,
            WinCrypt.CMSG_ENCODED_MESSAGE,
            0,
            IntPtr.Zero,
            ref cbData))
        {
            throw new Win32Exception(Marshal.GetLastWin32Error());
        }

        var vData = new byte[cbData];

        // Get the encoded message.
        if (!WinCrypt.CryptMsgGetParam(
            cryptMsg,
            WinCrypt.CMSG_ENCODED_MESSAGE,
            0,
            vData,
            ref cbData))
        {
            throw new Win32Exception(Marshal.GetLastWin32Error());
        }

        var signedCms = new SignedCms();
        signedCms.Decode(vData);

        if (signedCms.SignerInfos.Count > 0)
        {
            var signerInfo = signedCms.SignerInfos[0];

            if (signerInfo.Certificate != null)
            {
                cert = signerInfo.Certificate;
            }
        }

        return cert;
    }

Il semble que si vous utilisez le "WinCrypt.Sur L'appel CryptQueryObject il souffre de la même les performances de mémoire frappent comme l'objet X509Certificate, mais si vous le réduisez aux seuls types de contenu PKCS7, il fonctionne comme un rêve et semble me donner les informations dont j'ai besoin.

Comme je vois que vous avez pas de réponses de toute façon, permettez-moi de vous offrir l'une.

si cela ne vous dérange pas d'utiliser des composants tiers, jetez un coup d'oeil à TElAuthenticodeVerifier composant de notre produit SecureBlackbox. Avec ce composant, vous pouvez vérifier la signature et vérifier les horodateurs.

j'aime l'idée d'éviter un code P/invoke désagréable en utilisant la classe SignedCms, mais sachez que dans certaines circonstances de réseau le constructeur SignedCms peut bloquer pendant longtemps - - - je vois environ 15 secondes sur un test que je suis en cours d'exécution. Alejandro Campos Magencio a des informations à ce sujet sur son blog MSDN dans un billet intitulé grand retard en appelant le constructeur EnvelopedCms.