topic Re: any way to remove password from a dwg in ObjectARX Forum

any way to remove password from a dwg

Anonymous — Tue, 24 Apr 2012 03:33:15 GMT

I want to remove password from dwgs whose password is know. I can open these dwgs by known pasword, but I can't find a way to save them without password.

        SecurityParams secParams;
       {
           secParams.cbSize = 48;
           secParams.ulFlags = 1;
           secParams.ulProvType = 1;
           secParams.ulAlgId = 26625;
           secParams.ulKeyLength = 40;
           secParams.wszPassword = szPassword;//if I give NULL to this param, the "saveAs" method crushes.
           secParams.wszProvName = _T("Microsoft Base Cryptographic Provider v1.0");
       }

es = pDb->saveAs(szFileName,&secParams);// I want to remove their passsword

Re: any way to remove password from a dwg

owenwengerd — Tue, 24 Apr 2012 04:09:34 GMT

Pass NULL for the second argument to saveAs().

Re: any way to remove password from a dwg

Anonymous — Wed, 25 Apr 2012 07:48:30 GMT

thanks, but are you sure? I tried the following code, it dosen't work. The password of the dwg still exists.

             AcDbDatabase* pDb = new AcDbDatabase(false);
           Acad::ErrorStatus es = pDb->readDwgFile(iterS->c_str(),_SH_DENYWR,false,szOldPassword);
           if (Acad::eOk == es)
           {
               if (_tcscmp(szPassword,_T("")) == 0)
               {
                   es = pDb->saveAs(iterS->c_str(),NULL);
               }
               else
               {
                   es = pDb->saveAs(iterS->c_str(),&secParams);
               }

               if (Acad::eOk == es ) ++nCount;
           }

Re: any way to remove password from a dwg

Alexander.Rivilis — Wed, 25 Apr 2012 07:58:36 GMT

Try:

secParams.wszPassword =_T("");

Re: any way to remove password from a dwg

Anonymous — Wed, 25 Apr 2012 08:06:43 GMT

CAD enters dead loop, If I pass an empty string(not null) .

Re: any way to remove password from a dwg

Alexander.Rivilis — Wed, 25 Apr 2012 08:19:50 GMT

What about save dwg with other filename without password?

There is a method AcDbDatabase::setSecurityParams. Try pass NULL to it.

Re: any way to remove password from a dwg

Anonymous — Wed, 25 Apr 2012 08:24:05 GMT

I tried, "save as" with a new file name, but the new dwg still has the same password from the old dwg.

Re: any way to remove password from a dwg

Alexander.Rivilis — Wed, 25 Apr 2012 09:01:07 GMT

OK. Working code:

static bool RemovePasswordProtection(AcDbDatabase *pDb)
{
    const SecurityParams *parSecOld = pDb->cloneSecurityParams();
    SecurityParams parSecNew = *parSecOld;
    parSecNew.ulFlags = 0; // Clear all security flags
    return (pDb->setSecurityParams(&parSecNew));
}
// Main function remove password from current drawing
static void PWDRemovePwd(void)
{
    AcDbDatabase *pCurDb  = acdbCurDwg();
    AcApDocument *pCurDoc = curDoc();
    RemovePasswordProtection(pCurDb);
    pCurDb->saveAs(pCurDoc->fileName(),NULL);
}

Re: any way to remove password from a dwg

Anonymous — Wed, 25 Apr 2012 09:23:45 GMT

thanks so much. It did work. I noticed that cad automatically remembers password , but found no way to remove this mechanism.