Question

I have a directory and a dynamic file name. Are there any functions I can use to make sure it is impossible to break out from the specified directory?

for example:

secure_path('/tmp/', 'file.txt') -> /tmp/file.txt
secure_path('/tmp/', '../file.txt') -> /tmp/file.txt

Answer 1

If you’re only working in the single directory and not subdirectories below you could do

$file = "/tmp/".basename($input);

Which should give you the filename at the end of any path given in input, and append it to the directory you wanted.