octoleo
/
qpdf
mirror of https://github.com/qpdf/qpdf.git
2
1
Fork 0
Code Issues Releases Wiki Activity

Manual: correct statement about empty owner passwords

This commit is contained in:
Jay Berkenbilt 2022-01-23 12:58:54 -05:00
parent 564dc03607
commit 2a2ec1c066
1 changed files with 7 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
manual/encryption.rst
View File

@ -383,13 +383,13 @@ reader treats the password as the owner password, using it to recover
the user password, and then uses the user password to retrieve the
encryption key. This is why creating a file with the same user
password and owner password with ``V`` < 5 results in a file that some
readers will never allow you to open as the owner. Typically when a
reader encounters a file with ``V`` < 5, it will first attempt to
treat the empty string as a user password. If that works, the file is
encrypted but not password-protected. If it doesn't work, then a
password prompt is given. Creating a file with an empty owner password
is like creating a file with the same owner and user password: there
is no way to open the file as an owner.
readers will never allow you to open as the owner. When an empty owner
password is given at file creation, the user password is used as both
the user and owner password. Typically when a reader encounters a file
with ``V`` < 5, it will first attempt to treat the empty string as a
user password. If that works, the file is encrypted but not
password-protected. If it doesn't work, then a password prompt is
given.
For ``V`` ≥ 5, the main encryption key is independently encrypted
using the user password and the owner password. There is no way to