"""openid.py: an openid library for web.py
Notes:
- This will create a file called .openid_secret_key in the
current directory with your secret key in it. If someone
has access to this file they can log in as any user. And
if the app can't find this file for any reason (e.g. you
moved the app somewhere else) then each currently logged
in user will get logged out.
- State must be maintained through the entire auth process
-- this means that if you have multiple web.py processes
serving one set of URLs or if you restart your app often
then log ins will fail. You have to replace sessions and
store for things to work.
- We set cookies starting with "openid_".
"""
import os
import random
import hmac
import __init__ as web
import openid.consumer.consumer
import openid.store.memstore
sessions = {}
store = openid.store.memstore.MemoryStore()
def _secret():
try:
secret = file('.openid_secret_key').read()
except IOError:
# file doesn't exist
secret = os.urandom(20)
file('.openid_secret_key', 'w').write(secret)
return secret
def _hmac(identity_url):
return hmac.new(_secret(), identity_url).hexdigest()
def _random_session():
n = random.random()
while n in sessions:
n = random.random()
n = str(n)
return n
def status():
oid_hash = web.cookies().get('openid_identity_hash', '').split(',', 1)
if len(oid_hash) > 1:
oid_hash, identity_url = oid_hash
if oid_hash == _hmac(identity_url):
return identity_url
return None
def form(openid_loc):
oid = status()
if oid:
return '''
<form method="post" action="%s">
<img src="http://openid.net/login-bg.gif" alt="OpenID" />
<strong>%s</strong>
<input type="hidden" name="action" value="logout" />
<input type="hidden" name="return_to" value="%s" />
<button type="submit">log out</button>
</form>''' % (openid_loc, oid, web.ctx.fullpath)
else:
return '''
<form method="post" action="%s">
<input type="text" name="openid" value=""
style="background: url(http://openid.net/login-bg.gif) no-repeat; padding-left: 18px; background-position: 0 50%%;" />
<input type="hidden" name="return_to" value="%s" />
<button type="submit">log in</button>
</form>''' % (openid_loc, web.ctx.fullpath)
def logout():
web.setcookie('openid_identity_hash', '', expires=-1)
class host:
def POST(self):
# unlike the usual scheme of things, the POST is actually called
# first here
i = web.input(return_to='/')
if i.get('action') == 'logout':
logout()
return web.redirect(i.return_to)
i = web.input('openid', return_to='/')
n = _random_session()
sessions[n] = {'webpy_return_to': i.return_to}
c = openid.consumer.consumer.Consumer(sessions[n], store)
a = c.begin(i.openid)
f = a.redirectURL(web.ctx.home, web.ctx.home + web.ctx.fullpath)
web.setcookie('openid_session_id', n)
return web.redirect(f)
def GET(self):
n = web.cookies('openid_session_id').openid_session_id
web.setcookie('openid_session_id', '', expires=-1)
return_to = sessions[n]['webpy_return_to']
c = openid.consumer.consumer.Consumer(sessions[n], store)
a = c.complete(web.input(), web.ctx.home + web.ctx.fullpath)
if a.status.lower() == 'success':
web.setcookie('openid_identity_hash', _hmac(a.identity_url) + ',' + a.identity_url)
del sessions[n]
return web.redirect(return_to)
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