验证文件签名

Sysinternal(http://forum.sysinternals.com/howto-verify-the-digital-signature-of-a-file_topic19247.html)上有关于验证签名的代码，不过代码有点问题，他只能验证PE签名，无法验证文件签名，所以我这里稍作了点修改，记录一下

#define ENCODING (X509_ASN_ENCODING | PKCS_7_ASN_ENCODING)

BOOL CheckFileTrust(LPCTSTR filename, CString &signer_file)
{
    HCATADMIN cat_admin_handle = NULL;
    if (!CryptCATAdminAcquireContext(&cat_admin_handle, NULL, 0))
    {
        return FALSE;
    }

    HANDLE hFile = CreateFileW(filename, GENERIC_READ, FILE_SHARE_READ,
        NULL, OPEN_EXISTING, 0, NULL);
    if (INVALID_HANDLE_VALUE == hFile)
    {
        CryptCATAdminReleaseContext(cat_admin_handle, 0);
        return FALSE;
    }

    DWORD hash_count = 100;
    BYTE hash_data[100];
    CryptCATAdminCalcHashFromFileHandle(hFile, &hash_count, hash_data, 0);
    CloseHandle(hFile);

    LPWSTR member_tag = new WCHAR[hash_count * 2 + 1];
    for (DWORD dw = 0; dw < hash_count; ++dw)
    {
        wsprintfW(&member_tag[dw * 2], L"%02X", hash_data[dw]);
    }

    WINTRUST_DATA wd = { 0 };
    WINTRUST_FILE_INFO wfi = { 0 };
    WINTRUST_CATALOG_INFO wci = { 0 };
    CATALOG_INFO ci = { 0 };
    HCATINFO cat_admin_info = CryptCATAdminEnumCatalogFromHash(cat_admin_handle,
        hash_data, hash_count, 0, NULL);
    if (NULL == cat_admin_info)
    {
        wfi.cbStruct = sizeof(WINTRUST_FILE_INFO);
        wfi.pcwszFilePath = filename;
        wfi.hFile = NULL;
        wfi.pgKnownSubject = NULL;

        wd.cbStruct = sizeof(WINTRUST_DATA);
        wd.dwUnionChoice = WTD_CHOICE_FILE;
        wd.pFile = &wfi;
        wd.dwUIChoice = WTD_UI_NONE;
        wd.fdwRevocationChecks = WTD_REVOKE_NONE;
        wd.dwStateAction = WTD_STATEACTION_IGNORE;
        wd.dwProvFlags = WTD_SAFER_FLAG;
        wd.hWVTStateData = NULL;
        wd.pwszURLReference = NULL;
        signer_file = filename;
    }
    else
    {
        CryptCATCatalogInfoFromContext(cat_admin_info, &ci, 0);
        wci.cbStruct = sizeof(WINTRUST_CATALOG_INFO);
        wci.pcwszCatalogFilePath = ci.wszCatalogFile;
        wci.pcwszMemberFilePath = filename;
        wci.pcwszMemberTag = member_tag;
        wci.pbCalculatedFileHash = hash_data;
        wci.cbCalculatedFileHash = hash_count;

        wd.cbStruct = sizeof(WINTRUST_DATA);
        wd.dwUnionChoice = WTD_CHOICE_CATALOG;
        wd.pCatalog = &wci;
        wd.dwUIChoice = WTD_UI_NONE;
        wd.fdwRevocationChecks = WTD_REVOKE_WHOLECHAIN;
        wd.dwProvFlags = 0;
        wd.hWVTStateData = NULL;
        wd.pwszURLReference = NULL;
        signer_file = ci.wszCatalogFile;
    }
    GUID action = WINTRUST_ACTION_GENERIC_VERIFY_V2;
    HRESULT hr = WinVerifyTrust(NULL, &action, &wd);
    BOOL retval = SUCCEEDED(hr);

    if (NULL != cat_admin_info) {
        CryptCATAdminReleaseCatalogContext(cat_admin_handle, cat_admin_info, 0);
    }
    CryptCATAdminReleaseContext(cat_admin_handle, 0);
    delete[] member_tag;
    return retval;
}

BOOL GetCertificateInfo(PCCERT_CONTEXT cert_context, CString &signer_name)
{
    LPTSTR name = NULL;
    DWORD data;

    if (!(data = CertGetNameString(cert_context,
        CERT_NAME_SIMPLE_DISPLAY_TYPE,
        0,
        NULL,
        NULL,
        0))) {
            return FALSE;
    }

    // Allocate memory for subject name.
    name = (LPTSTR)LocalAlloc(LPTR, data * sizeof(TCHAR));
    if (!name) {
        return FALSE;
    }

    // Get subject name.
    if (!(CertGetNameString(cert_context,
        CERT_NAME_SIMPLE_DISPLAY_TYPE,
        0,
        NULL,
        name,
        data))) {

            LocalFree(name);
            return FALSE;
    }
    signer_name = name;
    LocalFree(name);
    return TRUE;
}


BOOL GetFileSigner(LPCTSTR szFileName, CString &signer_name)
{
    HCERTSTORE store_handle = NULL;
    HCRYPTMSG msg_handle = NULL;
    PCCERT_CONTEXT cert_context = NULL;
    BOOL retval = FALSE;
    DWORD encoding, content_type, format_type;
    PCMSG_SIGNER_INFO signer_info = NULL;
    DWORD signer_info_size;
    CERT_INFO cert_info;
    do
    {
        // Get message handle and store handle from the signed file.
        retval = CryptQueryObject(CERT_QUERY_OBJECT_FILE,
            szFileName,
            CERT_QUERY_CONTENT_FLAG_PKCS7_SIGNED_EMBED,
            CERT_QUERY_FORMAT_FLAG_BINARY,
            0,
            &encoding,
            &content_type,
            &format_type,
            &store_handle,
            &msg_handle,
            NULL);
        if (!retval) {
            break;
        }

        // Get signer information size.
        retval = CryptMsgGetParam(msg_handle,
            CMSG_SIGNER_INFO_PARAM,
            0,
            NULL,
            &signer_info_size);
        if (!retval) {
            break;
        }

        // Allocate memory for signer information.
        signer_info = (PCMSG_SIGNER_INFO)LocalAlloc(LPTR, signer_info_size);
        if (!signer_info) {
            break;
        }

        // Get Signer Information.
        retval = CryptMsgGetParam(msg_handle,
            CMSG_SIGNER_INFO_PARAM,
            0,
            (PVOID)signer_info,
            &signer_info_size);
        if (!retval) {
            break;
        }


        // Search for the signer certificate in the temporary 
        // certificate store.
        cert_info.Issuer = signer_info->Issuer;
        cert_info.SerialNumber = signer_info->SerialNumber;

        cert_context = CertFindCertificateInStore(store_handle,
            ENCODING,
            0,
            CERT_FIND_SUBJECT_CERT,
            (PVOID)&cert_info,
            NULL);
        if (!cert_context) {
            break;
        }

        retval = GetCertificateInfo(cert_context, signer_name);

    } while (0);

    if (signer_info != NULL) { 
        LocalFree(signer_info); 
    }
    if (cert_context != NULL) {
        CertFreeCertificateContext(cert_context);
    }
    if (store_handle != NULL) {
        CertCloseStore(store_handle, 0);
    }
    if (msg_handle != NULL) {
        CryptMsgClose(msg_handle);
    }

    return retval;
}