Load password protected Zip files dynamically

[ManWithNoName]

I’m almost there. Almost there -- almost there I tell you. In the last 24h (literally -- I haven’t slept at all) I learnt PHP 5.2 Zip stuff, mcrypt, and a little about how to launch external programs from php. (exec/system).

Now. My problem.

I have a zip protected file, that I need to load “on demand”, so that I can stream its content.

TheZipFile.zip
|-- secretStashOfSecretFiles

I can load the zip file using the exec/system function

[PHP]exec("c:/winzip32 -e -sPassword TheFile.zip folderInZipFileToExtract) [/PHP]

That above line of code extracts the entire zip file. And it does so either before php loads the file or after -- I want it to extract the content when it loads the file… (Because when php loads the file it will return a nice tidally little error message proudly stating that permission is denied to the file).

All I want is that when php hits the password protected file it will enter it nicely and continue streaming.

Please please, pretty please sugar on the top of a hill cake of… eh—more sugar. Sprinkled with sweet sweet sugar. I have been googling-goggling for a very long time. Please please help me.

[ManWithNoName]

I have found the following functions of interest:

passthru
popen
proc_open

But I fail to see how they can help me.

Just to summarize:

I need to combine
[PHP]fopen('zip://file.zip#folder/file');[/PHP]
with
[PHP]system("c:/winzip -e -sPassword pathToZipFile extractTo");[/PHP]
So that it will stream a zip file that is password protected.

[ManWithNoName]

Notes for future self.

I found something interesting, opening the encrypted file

[PHP]fopen('zip://file.zip#folder/file');[/PHP]

will result in a garbage string. I'm guessing that winzip encrypts each file ("Encryption applies only to the contents of files stored within a Zip file."), and then stores them. In other words, that "garbage" string should be useful, that is if it could be decrypted.

see

AES Encryption Information: Encryption Specification AE-1 and AE-2

and

AES Coding Tips for Developers

I'm guessing that if you can get hold of the relevant variables you could decrypt the content "manually" with PHP. But, then again, I'm way over my head now.

Giving that there is zero interest for this thread, I'm officially giving up.

.. Oh well. Back to school...