passlib.ext.django - Django Password Hashing Plugin

New in version 1.6.

This module contains a Django plugin which overriddes all of Django’s password hashing functions, replacing them with wrappers around a Passlib CryptContext object whose configuration is controled from Django’s settings. While this extension’s utility is diminished with the advent of Django 1.4’s hashers framework, this plugin still has a number of uses:

• Make use of the new Django 1.4 pbkdf2 & bcrypt formats, even under earlier Django releases.
• Allow your application to work with any password hash format supported by Passlib, allowing you to import existing hashes from other systems. Common examples include SHA512-Crypt, PHPass, and BCrypt.
• Set different iterations / cost settings based on the type of user account, and automatically update hashes that use weaker settings when the user logs in.
• Mark any hash algorithms as deprecated, and automatically migrate to stronger hashes when the user logs in.

Warning

This plugin should be considered “release candidate” quality. It works, and has good unittest coverage, but has seen only limited real-world use. Please report any issues. It has been tested with Django 0.9.6 - 1.4.

Installation

Installation is simple: once Passlib itself has been installed, just add "passlib.ext.django" to Django’s settings.INSTALLED_APPS, as soon as possible after django.contrib.auth.

Once installed, this plugin will automatically monkeypatch Django to use a Passlib CryptContext instance in place of the normal Django password authentication routines (as an unfortunate side effect, this disables Django 1.4’s hashers framework entirely, though the default configuration supports all the built-in Django 1.4 hashers).

Configuration

While this plugin will function perfectly well without setting any configuration options, you can customize it using the following options in Django’s settings.py:

PASSLIB_CONFIG

This option specifies the CryptContext configuration options that will be used when the plugin is loaded.

• It’s value will usually be an INI-formatted string or a dictionary, containing options to be passed to CryptContext.
• Alternately, it can be the name of any preset supported by get_preset_config(), such as "passlib-default" or "django-default".
• Finally, it can be the special string "disabled", which will disable this plugin.

At any point after this plugin has been loaded, you can serialize it’s current configuration to a string:

>>> from passlib.ext.django.models import password_context
>>> print password_context.to_string()

This string can then be modified, and used as the new value of PASSLIB_CONFIG.

Note

It is strongly recommended to use a configuration which will support the existing Django hashes. Dumping and then modifying one of the preset strings is a good starting point.

PASSLIB_GET_CATEGORY

By default, Passlib will assign users to one of three categories: "superuser", "staff", or None; based on the attributes of the User object. This allows PASSLIB_CONFIG to have per-category policies, such as a larger number of iterations for the superuser account.

This option allows overidding the function which performs this mapping, so that more fine-grained / alternate user categories can be used. If specified, the function should have the call syntax get_category(user) -> category_string|None.

See also

See User Categories for more details.

PASSLIB_CONTEXT

Deprecated since version 1.6: This is a deprecated alias for PASSLIB_CONFIG, used by the (undocumented) version of this plugin that was released with Passlib 1.5. It should not be used by new applications.

Module Contents

passlib.ext.django.models.password_context

The CryptContext instance that drives this plugin. It can be imported and examined to inspect the current configuration, changes made to it will immediately alter how Django hashes passwords.

passlib.ext.django.utils.get_preset_config(name)

Returns configuration string for one of the preset strings supported by the PASSLIB_CONFIG setting. Currently supported presets:

• "passlib-default" - default config used by this release of passlib.
• "django-default" - config matching currently installed django version.
• "django-latest" - config matching newest django version (currently same as "django-1.4").
• "django-1.0" - config used by stock Django 1.0 - 1.3 installs
• "django-1.4" -config used by stock Django 1.4 installs

passlib.ext.django.utils.PASSLIB_DEFAULT

This constant contains the default configuration for PASSLIB_CONFIG. It provides the following features:

• uses django_pbkdf2_sha256 as the default algorithm.
• supports all of the Django 1.0-1.4 hash formats.
• additionally supports SHA512-Crypt, BCrypt, and PHPass.
• is configured to use a larger number of rounds for the superuser account.
• is configured to automatically migrate all Django 1.0 hashes to use the default hash as soon as each user logs in.

As of Passlib 1.6, it contains the following string:

[passlib]

; list of schemes supported by configuration
; currently all django 1.4 hashes, django 1.0 hashes,
; and three common modular crypt format hashes.
schemes =
    django_pbkdf2_sha256, django_pbkdf2_sha1, django_bcrypt,
    django_salted_sha1, django_salted_md5, django_des_crypt, hex_md5,
    sha512_crypt, bcrypt, phpass

; default scheme to use for new hashes
default = django_pbkdf2_sha256

; hashes using these schemes will automatically be re-hashed
; when the user logs in (currently all django 1.0 hashes)
deprecated =
    django_pbkdf2_sha1, django_salted_sha1, django_salted_md5,
    django_des_crypt, hex_md5

; sets some common options, including minimum rounds for two primary hashes.
; if a hash has less than this number of rounds, it will be re-hashed.
all__vary_rounds = 0.05
sha512_crypt__min_rounds = 80000
django_pbkdf2_sha256__min_rounds = 10000

; set somewhat stronger iteration counts for ``User.is_staff``
staff__sha512_crypt__default_rounds = 100000
staff__django_pbkdf2_sha256__default_rounds = 12500

; and even stronger ones for ``User.is_superuser``
superuser__sha512_crypt__default_rounds = 120000
superuser__django_pbkdf2_sha256__default_rounds = 15000