Confusion between User Access Permissions & Document Security Restrictions

[eabase]

There seem to be some confusion between User Access Permissions and Document [Security] Restrictions, when handling permissions. (Or at least I am confused, because it looks like you are mixing up the two.)

• User Access Permissions is used for setting permissions on encrypted files requiring a password.

• Document [Security] Restrictions can be set on any PDF file (without encryption)

• There is also an ambiguous DeprecationWarning that tell you to use another thing, and then doesn't work.

Looking at some PDF document you can have the Document [Security] Restrictions as shown in Adobe Acrobat, without any Encryption.

Here's how my PDF looks.
(Sorry, I cannot share it as it belongs to a company.)

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So if I have a non-encrypted PDF with the following restrictions:

EXTRACT_TEXT_AND_GRAPHICS 
ASSEMBLE_DOC

(512 and 1024, respectively)

The question is:

1. How do I read these from the PDF?
2. How do I change them in the same PDF?

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Environment

Which environment were you using when you encountered the problem?

# python -m platform
Windows-10-10.0.22000-SP0

# python -c "import pypdf;print(pypdf._debug_versions)"
pypdf==4.1.0, crypt_provider=('cryptography', '42.0.5'), PIL=10.3.0

Code + PDF

This is a REPL example that shows the issue:

import pypdf
from pypdf import PdfReader, PdfWriter
from pypdf.constants import UserAccessPermissions

IFILE = 'some.pdf'
reader = PdfReader(IFILE)

reader.decode_permissions(UserAccessPermissions.all())
# ...
# <stdin>:1: DeprecationWarning: decode_permissions is deprecated and will be removed in pypdf 5.0.0. Use user_access_permissions instead.

reader.user_access_permissions(UserAccessPermissions.all())
# TypeError: 'NoneType' object is not callable

[stefan6419846]

It seems like you are mixing up something: A PDF file can have a user password and an owner password. The user password is required each time you open the file. An owner password is used to restrict the permissions a regular user (without specifying the owner password) should be allowed to do.

You are correct that decode_permissions has been deprecated as this rather is a property on the document. Nevertheless, you are using both functionality wrong (see #2389 (comment) as well): You either want

• reader.decode_permissions(reader._encryption.P) (deprecated) or
• reader.user_access_permissions (flags instance) or reader.user_access_permissions.to_dict() (dictionary similar to the one from decode_permissions().

Alternatively, you might pass any set of permission flag value into UserAccessPermissions() to get a verbose representation of it.

To change the permissions, use PdfWriter.encrypt() with the appropriate parameters.