py_sip_xnu

Python module for querying SIP status on XNU-based systems (primarily macOS) through exposed kernel APIs. No reliance on csrutil or NVRAM properties, allowing for more accurate and reliable results. Supporting both Intel and Apple Silicon systems.

Library returns a SIP object with the following properties:

value                    - int    - raw value of SIP configuration
breakdown                - object - holds each SIP key and its value
can_edit_root            - bool   - whether SIP allows editing of protected files
can_write_nvram          - bool   - whether SIP allows writing to NVRAM
can_load_arbitrary_kexts - bool   - whether SIP allows loading of arbitrary kexts

If module accessed under Yosemite or earlier, sip_xnu will treat SIP as disabled.

Project currently synced against macOS 13.0 (XNU 8792.41.9). Based off of pudquick's concept.

Python validated against 2.7 and 3.9.

Background

System Integrity Protection, generally abbreviated as SIP, is a security feature introduced in OS X El Capitan. The primary purpose of this setting was to control access to sensitive operations such as kernel extension loading, protected file write, task tracking, etc. SIP is part of the XNU kernel, and is a cumulation of several kernel flags into the CSR bitmask seen as SIP configuration.

The primary benefit of this library over manually invoking either csrutil or reading nvram csr-active-config is that we check with the kernel directly, and verify what macOS itself is using for SIP configuration. Contrast this with nvram, boot.efi and XNU can reject SIP bits such as 0x10 (AppleInternal) during runtime without changing the exposed NVRAM value.

With csrutil, this tool obfuscates much of SIP into a simple on/off state, when in reality SIP is a complex bitmask. Many developers will simply check the output of csrutil status and assume SIP is either enabled or disabled, without properly probing specific bits for what the application may need. Using sip_xnu allows for better probing and allows users to lower less of SIP for overall better system security.

• More information can be found here: System Integrity Protection: The misunderstood setting

Source for SIP configuration can be found in Apple's csr.h, and parsing logic from csr.c.

Installation

pip-based:

pip3 install py_sip_xnu

Manual:

python3 setup.py install

Usage

Invocation:

import py_sip_xnu

sip_config = py_sip_xnu.SipXnu().get_sip_status()

'''
sip_config = {
    'value': 0,
    'breakdown': {
        'csr_allow_untrusted_kexts': False,
        'csr_allow_unrestricted_fs': False,
        'csr_allow_task_for_pid': False,
        'csr_allow_kernel_debugger': False,
        'csr_allow_apple_internal': False,
        'csr_allow_unrestricted_dtrace': False,
        'csr_allow_unrestricted_nvram': False,
        'csr_allow_device_configuration': False,
        'csr_allow_any_recovery_os': False,
        'csr_allow_unapproved_kexts': False,
        'csr_allow_executable_policy_override': False,
        'csr_allow_unauthenticated_root': False
    },
    'can_edit_root': False,
    'can_write_nvram': False,
    'can_load_arbitrary_kexts': False
}
'''

License

BSD 3-Clause License

Copyright (c) 2022, Mykola Grymalyuk