I am trying to understand how encrypted ("password protected") Office 2007 documents are bundled (specifically, Excel documents). I am experimenting with a known, password protected spread sheet.
When I unzip the XLSX file, I encounter three entries:
- [6]DataSpaces (Directory)
- EncryptionInfo (File)
- EncryptedPackage (File)
How is the EncryptedPackage file encrypted (which cipher, which key derivation function, etc...)?
I have tried referencing the documentation, but I haven't had much success.