C# Signature:

  [Flags]
  public enum MSISIGINFO : uint
  {
      None = 0,
      MSI_INVALID_HASH_IS_FATAL = 1
  }

  public enum HRESULT
  {
      S_OK = unchecked(0x00000000),
      S_FALSE = unchecked(0x00000001),
      E_FAIL = unchecked((int)0x80004005),
      E_INVALIDARG = unchecked((int)0x80070057),
      E_MOREDATA = unchecked((int)0x800700EA),
      E_OUTOFMEMORY = unchecked((int)0x8007000E),
      ERROR_FUNCTION_FAILED = unchecked((int)0x8007065B),
      TRUST_E_NOSIGNATURE = unchecked((int)0x800B0100),
      TRUST_E_BAD_DIGEST = unchecked((int)0x80096010),
      CERT_E_REVOKED = unchecked((int)0x800B010C),
      TRUST_E_SUBJECT_NOT_TRUSTED = unchecked((int)0x800B0004),
      TRUST_E_PROVIDER_UNKNOWN = unchecked((int)0x800B0001),
      TRUST_E_ACTION_UNKNOWN = unchecked((int)0x800B0002),
      TRUST_E_SUBJECT_FORM_UNKNOWN = unchecked((int)0x800B0003),
  }

  [StructLayout(LayoutKind.Sequential)]
  public struct CERT_CONTEXT
  {
[StructLayout(LayoutKind.Sequential)]
public struct CERT_CONTEXT
{
      public CertEncodingType dwCertEncodingType;
      public IntPtr pbCertEncoded;
      public uint cbCertEncoded;
      public IntPtr pCertInfo;
      public IntPtr hCertStore;
  }
}

  [DllImport("msi.dll", CharSet = CharSet.Unicode)]
  [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
  public static extern HRESULT MsiGetFileSignatureInformation(
      [In] string szSignedObjectPath,
      [In] MSISIGINFO dwFlags,
      [In, Out] ref IntPtr ppcCertContext,
      [Out] byte[] pbHashData,
      [In, Out] ref int pcbHashData);

Notes:

You will also need CertFreeCertificateContext to free pCertContext.

Tips & Tricks:

Please add some!

Sample Code:

  CERT_CONTEXT certContext = default;
  try
  {
      // - First call gets the hash data buffer size.
      // - Second call gets the hash data for real.
      byte[] pbHashData = Array.Empty<byte>();
      int pcbHashData = 0;
      HRESULT hresult = HRESULT.E_MOREDATA;
      for (int i = 0; i < 2 && hresult == HRESULT.E_MOREDATA; i++)
      {
          hresult = MsiGetFileSignatureInformation(
          msiFilePath,
          MSISIGINFO.MSI_INVALID_HASH_IS_FATAL,
          ref pCertContext,
          pbHashData,
          ref pcbHashData);

          if (hresult == HRESULT.E_MOREDATA)
          {
              // pbHashData is ready to use now.
              pbHashData = new byte[pcbHashData];
          }
      }

      // Copy PCCERT_CONTEXT from the unmanaged space to CERT_CONTEXT in managed space.
      // certContext is ready to use now.
      certContext =
          pCertContext == IntPtr.Zero
          ? default
          : Marshal.PtrToStructure<CERT_CONTEXT>(pCertContext);
  }
  finally
  {
      // The PCCERT_CONTEXT returned by MsiGetFileSignatureInformation must be
      // freed with CertFreeCertificateContext.
      if (pCertContext != IntPtr.Zero)
      {
          CertFreeCertificateContext(pCertContext);
      }
  }

Alternative Managed API:

Do you know one? Please contribute it!

Documentation:

MsiGetFileSignatureInformationW on MSDN

CertFreeCertificateContext on P/Invoke

Please edit this page!

Do you have...

• helpful tips or sample code to share for using this API in managed code?
• corrections to the existing content?
• variations of the signature you want to share?
• additional languages you want to include?

Select "Edit This Page" on the right hand toolbar and edit it! Or add new pages containing supporting types needed for this API (structures, delegates, and more).