Fourstones at 10:50, 12 November 2008

2008-11-12T10:50:28Z

Fourstones: New page: Category:ccHost Category:ccMixter Category:Developer Category:Software Category:Technology {{draft}} {{lowercase}} {{Infobox|NOTE: This code is untested. It is only the...

2008-11-06T20:21:25Z

New page: Category:ccHost Category:ccMixter Category:Developer Category:Software Category:Technology {{draft}} {{lowercase}} {{Infobox|NOTE: This code is untested. It is only the...

New page

[[Category:ccHost]]
[[Category:ccMixter]]
[[Category:Developer]]
[[Category:Software]]
[[Category:Technology]]
{{draft}}
{{lowercase}}
{{Infobox|NOTE: This code is untested. It is only theoretical until someone can verify it works as advertised.}}
The ccHost philosophy for file verifying is a whitelist - a list of file types to be accepted, all others rejected. At least one installation has chosen to implement a blacklist instead. The portable way to do this is to use ccHost's verify hook - basically a global variable.

The following code is a skeleton of how to hook the system. The actual blacklisting algorithm is left as an exercise for the reader. Put this code into a file '''<local_files>/lib/blacklist_validator.php''':

<nowiki><?</nowiki>

// the uploader looks for this variable:

global $CC_UPLOAD_VALIDATOR;

// set the global to our validator factory...

$CC_UPLOAD_VALIDATOR = 'make_blacklist_validator';

function make_blacklist_validator()
{
return new Blacklist_Validator(true); // set this to false if you don't want to
// delegate to the system's validator
}

/**
* Blacklist_Validator
*
* Replace (or override) the existing whitelist base verifier
* with an alternate version
*
*/
class Blacklist_Validator
{
var $old_validator; // store a pointer to the system validator
var $do_delegation; // flag as to whether to delegate to the system.

function Blacklist_Validator($do_delegation=true)
{
$this->do_delegation = $do_delegation;

if( $this->do_delegation )
{
require_once('cchost_lib/ccextras/cc-pseudo-verify.inc');
$this->old_validator = new CCPseudoVerifyAPI();
}
}

function GetValidFileTypes(&$types)
{
if( $this->do_delegation )
{
$retval = $this->old_validator->GetValidFileTypes($types);
}
else
{
$retval = true;
}

$types[] = '*.*';
return $retval;
}

function FileValidate(&$formatinfo)
{
if( $this->do_delegation )
{
$retval = $this->old_validator->FileValidate($formatinfo);
if( $retval )
return true;
}
else
{
if( !is_array( $types ) )
$types = array();
$retval = false;
}

$path = $formatinfo->GetFilePath();

// things really break down if we don't have a
// file extension so we just reject them out
// of hand

$got_ext = <nowiki>preg_match( '/\.([a-z0-9]+)$/', strtolower($path), $m )</nowiki>;

if( !$got_ext )
{
$formatinfo->SetErrors( _('Cannot determine file type'));
return false;
}

/***********************************
* Edit the code below here... *
***********************************/

$retval = 1 ? true : false; // <<<---- your verification code goes here

if( $retval )
{
$FI['tags'] = 'archive,' . $m[0]; // tags here will be added to
$FI['default-ext'] = $m[0]; // your default extension goes here
$FI['media-type'] = 'archive'; // media type (e.g. video, audio, image, archive, etc.)
$FI['mime_type'] = 'octect/stream'; // or whatever you think

$formatinfo->SetData( $FI );
$formatinfo->_errors = <nowiki>''</nowiki>;
}

return $retval;
}

}
<nowiki>?></nowiki>

@@ Line 4: / Line 4: @@
 [[Category:Software]]
 [[Category:Technology]]
-{{draft}}
+{{cchost_head}}
 {{lowercase}}
-{{Infobox|NOTE: This code is untested. It is only theoretical until someone can verify it works as advertised.}}
 The ccHost philosophy for file verifying is a whitelist - a list of file types to be accepted, all others rejected. At least one installation has chosen to implement a blacklist instead. The portable way to do this is to use ccHost's verify hook - basically a global variable.

Cchost/developer/tutorial/Replacing the File Verifier - Revision history

Fourstones at 10:50, 12 November 2008

Fourstones: New page: Category:ccHost Category:ccMixter Category:Developer Category:Software Category:Technology {{draft}} {{lowercase}} {{Infobox|NOTE: This code is untested. It is only the...