# -*- test-case-name: twisted.web.test.test_httpauth -*-
# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.
"""
HTTP BASIC authentication.
@see: U{http://tools.ietf.org/html/rfc1945}
@see: U{http://tools.ietf.org/html/rfc2616}
@see: U{http://tools.ietf.org/html/rfc2617}
"""
from __future__ import division, absolute_import
import binascii
from zope.interface import implementer
from twisted.cred import credentials, error
from twisted.web.iweb import ICredentialFactory
@implementer(ICredentialFactory)
class BasicCredentialFactory(object):
"""
Credential Factory for HTTP Basic Authentication
@type authenticationRealm: L{bytes}
@ivar authenticationRealm: The HTTP authentication realm which will be issued in
challenges.
"""
scheme = b'basic'
def __init__(self, authenticationRealm):
self.authenticationRealm = authenticationRealm
def getChallenge(self, request):
"""
Return a challenge including the HTTP authentication realm with which
this factory was created.
"""
return {'realm': self.authenticationRealm}
def decode(self, response, request):
"""
Parse the base64-encoded, colon-separated username and password into a
L{credentials.UsernamePassword} instance.
"""
try:
creds = binascii.a2b_base64(response + b'===')
except binascii.Error:
raise error.LoginFailed('Invalid credentials')
creds = creds.split(b':', 1)
if len(creds) == 2:
return credentials.UsernamePassword(*creds)
else:
raise error.LoginFailed('Invalid credentials')