From c45e6d34b1beb44d4eb7cecd6426f6c762249484 Mon Sep 17 00:00:00 2001 From: kali Date: Fri, 19 Oct 2012 11:01:27 +0900 Subject: srp authentication class + useful decorator --- src/leap/base/auth.py | 158 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 158 insertions(+) diff --git a/src/leap/base/auth.py b/src/leap/base/auth.py index c34ad39b..1f93c9c3 100644 --- a/src/leap/base/auth.py +++ b/src/leap/base/auth.py @@ -1,15 +1,22 @@ import binascii +import json import logging +import urlparse import requests import srp +from PyQt4 import QtCore + from leap.base import constants as baseconstants logger = logging.getLogger(__name__) SIGNUP_TIMEOUT = getattr(baseconstants, 'SIGNUP_TIMEOUT', 5) +# XXX remove me!! +SERVER = "http://springbok/1" + class LeapSRPRegister(object): @@ -85,3 +92,154 @@ class LeapSRPRegister(object): # we catch it in the form #req.raise_for_status() return (req.ok, req) + + +class SRPAuthenticationError(Exception): + """ + exception raised + for authentication errors + """ + pass + +safe_unhexlify = lambda x: binascii.unhexlify(x) \ + if (len(x) % 2 == 0) else binascii.unhexlify('0' + x) + + +class SRPAuth(requests.auth.AuthBase): + + def __init__(self, username, password): + self.username = username + self.password = password + + # XXX init something similar to + # SERVER... + + self.init_data = None + self.session = requests.session() + + self.init_srp() + + def get_data(self, response): + return json.loads(response.content) + + def init_srp(self): + usr = srp.User( + self.username, + self.password, + srp.SHA256, + srp.NG_1024) + uname, A = usr.start_authentication() + + self.srp_usr = usr + self.A = A + + def get_auth_data(self): + return { + 'login': self.username, + 'A': binascii.hexlify(self.A) + } + + def get_init_data(self): + init_session = self.session.post( + SERVER + '/sessions', + data=self.get_auth_data()) + self.init_data = self.get_data(init_session) + return self.init_data + + def authenticate(self): + print 'start authentication...' + + init_data = self.get_init_data() + salt = init_data.get('salt', None) + B = init_data.get('B', None) + + if not salt or not B: + raise SRPAuthenticationError + + self.M = self.srp_usr.process_challenge( + safe_unhexlify(salt), + safe_unhexlify(B) + ) + + auth_result = self.session.put( + SERVER + '/sessions/' + self.username, + data={'client_auth': binascii.hexlify(self.M)}) + + # XXX check for errors + auth_data = self.get_data(auth_result) + self.srp_usr.verify_session( + safe_unhexlify(auth_data["M2"])) + + try: + assert self.srp_usr.authenticated() + print 'user is authenticated!' + except (AssertionError): + raise SRPAuthenticationError + + def __call__(self, req): + self.authenticate() + req.session = self.session + return req + + +def srpauth_protected(user=None, passwd=None): + """ + decorator factory that accepts + user and password keyword arguments + and add those to the decorated request + """ + def srpauth(fn, user=user, passwd=passwd): + def wrapper(*args, **kwargs): + print 'uri is ', args[0] + if user and passwd: + auth = SRPAuth(user, passwd) + kwargs['auth'] = auth + return fn(*args, **kwargs) + return wrapper + return srpauth + + +def magic_srpauth(fn): + """ + decorator that gets user and password + from the config file and adds those to + the decorated request + """ + # TODO --- finish this... + def wrapper(*args, **kwargs): + uri = args[0] + # XXX Ugh! + # Problem with this approach. + # This won't work when we're using + # api.foo.bar + # Unless we keep a table with the + # equivalencies... + + domain = urlparse.urlparse(uri).netloc + + # XXX check this settings init... + settings = QtCore.QSettings() + user = settings.get('%s_username' % domain, None) + + # uh... I forgot. + # get secret? + # leapkeyring.get_password(foo?) + passwd = settings.get('%s_password' % domain, None) + + auth = SRPAuth(user, passwd) + kwargs['auth'] = auth + return fn(*args, **kwargs) + return wrapper + + +if __name__ == "__main__": + + TEST_USER = "test1" + TEST_PASS = "1234" + + @srpauth_protected(user=TEST_USER, passwd=TEST_PASS) + def test_srp_protected_get(*args, **kwargs): + req = requests.get(*args, **kwargs) + print req.content + + test_srp_protected_get('http://springbok/1/cert') -- cgit v1.2.3