people: Add groups to navigation

[ipfire.org.git] / src / backend / accounts.py

#!/usr/bin/python
# encoding: utf-8

import base64
import datetime
import hmac
import json
import ldap
import ldap.modlist
import logging
import os
import phonenumbers
import re
import time
import tornado.httpclient
import urllib.parse
import urllib.request
import zxcvbn

from . import countries
from . import util
from .decorators import *
from .misc import Object

# Set the client keytab name
os.environ["KRB5_CLIENT_KTNAME"] = "/etc/ipfire.org/ldap.keytab"

class Accounts(Object):
	def init(self):
		self.search_base = self.settings.get("ldap_search_base")

	def __iter__(self):
		# Only return developers (group with ID 1000)
		accounts = self._search("(&(objectClass=posixAccount)(gidNumber=1000))")

		return iter(sorted(accounts))

	@lazy_property
	def ldap(self):
		# Connect to LDAP server
		ldap_uri = self.settings.get("ldap_uri")

		logging.debug("Connecting to LDAP server: %s" % ldap_uri)

		# Connect to the LDAP server
		return ldap.ldapobject.ReconnectLDAPObject(ldap_uri,
			retry_max=10, retry_delay=3)

	def _authenticate(self):
		# Authenticate against LDAP server using Kerberos
		self.ldap.sasl_gssapi_bind_s()

	def test_ldap(self):
		logging.info("Testing LDAP connection...")

		self._authenticate()

		logging.info("Successfully authenticated as %s" % self.ldap.whoami_s())

	def _query(self, query, attrlist=None, limit=0, search_base=None):
		logging.debug("Performing LDAP query (%s): %s" \
			% (search_base or self.search_base, query))

		t = time.time()

		results = self.ldap.search_ext_s(search_base or self.search_base,
			ldap.SCOPE_SUBTREE, query, attrlist=attrlist, sizelimit=limit)

		# Log time it took to perform the query
		logging.debug("Query took %.2fms" % ((time.time() - t) * 1000.0))

		return results

	def _search(self, query, attrlist=None, limit=0):
		accounts = []
		for dn, attrs in self._query(query, attrlist=["dn"], limit=limit):
			account = self.get_by_dn(dn)
			accounts.append(account)

		return accounts

	def _get_attrs(self, dn):
		"""
			Fetches all attributes for the given distinguished name
		"""
		results = self._query("(objectClass=*)", search_base=dn, limit=1,
			attrlist=("*", "createTimestamp", "modifyTimestamp"))

		for dn, attrs in results:
			return attrs

	def get_by_dn(self, dn):
		attrs = self.memcache.get("accounts:%s:attrs" % dn)
		if attrs is None:
			attrs = self._get_attrs(dn)
			assert attrs, dn

			# Cache all attributes for 5 min
			self.memcache.set("accounts:%s:attrs" % dn, attrs, 300)

		return Account(self.backend, dn, attrs)

	def get_created_after(self, ts):
		t = ts.strftime("%Y%m%d%H%M%SZ")

		return self._search("(&(objectClass=person)(createTimestamp>=%s))" % t)

	def search(self, query):
		# Search for exact matches
		accounts = self._search(
			"(&(objectClass=person)(|(uid=%s)(mail=%s)(sipAuthenticationUser=%s)(telephoneNumber=%s)(homePhone=%s)(mobile=%s)))" \
			% (query, query, query, query, query, query))

		# Find accounts by name
		if not accounts:
			for account in self._search("(&(objectClass=person)(|(cn=*%s*)(uid=*%s*)))" % (query, query)):
				if not account in accounts:
					accounts.append(account)

		return sorted(accounts)

	def _search_one(self, query):
		results = self._search(query, limit=1)

		for result in results:
			return result

	def uid_is_valid(self, uid):
		# UID must be at least four characters
		if len(uid) <= 4:
			return False

		# https://unix.stackexchange.com/questions/157426/what-is-the-regex-to-validate-linux-users
		m = re.match(r"^[a-z_]([a-z0-9_-]{0,31}|[a-z0-9_-]{0,30}\$)$", uid)
		if m:
			return True

		return False

	def uid_exists(self, uid):
		if self.get_by_uid(uid):
			return True

		res = self.db.get("SELECT 1 FROM account_activations \
			WHERE uid = %s AND expires_at > NOW()", uid)

		if res:
			return True

		# Account with uid does not exist, yet
		return False

	def get_by_uid(self, uid):
		return self._search_one("(&(objectClass=person)(uid=%s))" % uid)

	def get_by_mail(self, mail):
		return self._search_one("(&(objectClass=inetOrgPerson)(mail=%s))" % mail)

	def find_account(self, s):
		account = self.get_by_uid(s)
		if account:
			return account

		return self.get_by_mail(s)

	def get_by_sip_id(self, sip_id):
		if not sip_id:
			return

		return self._search_one(
			"(|(&(objectClass=sipUser)(sipAuthenticationUser=%s))(&(objectClass=sipRoutingObject)(sipLocalAddress=%s)))" \
			% (sip_id, sip_id))

	def get_by_phone_number(self, number):
		if not number:
			return

		return self._search_one(
			"(&(objectClass=inetOrgPerson)(|(sipAuthenticationUser=%s)(telephoneNumber=%s)(homePhone=%s)(mobile=%s)))" \
			% (number, number, number, number))

	@tornado.gen.coroutine
	def check_spam(self, uid, email, address):
		sfs = StopForumSpam(self.backend, uid, email, address)

		# Get spam score
		score = yield sfs.check()

		return score >= 50

	def auth(self, username, password):
		# Find account
		account = self.backend.accounts.find_account(username)

		# Check credentials
		if account and account.check_password(password):
			return account

	# Registration

	def register(self, uid, email, first_name, last_name, country_code=None):
		# Convert all uids to lowercase
		uid = uid.lower()

		# Check if UID is valid
		if not self.uid_is_valid(uid):
			raise ValueError("UID is invalid: %s" % uid)

		# Check if UID is unique
		if self.uid_exists(uid):
			raise ValueError("UID exists: %s" % uid)

		# Generate a random activation code
		activation_code = util.random_string(36)

		# Create an entry in our database until the user
		# has activated the account
		self.db.execute("INSERT INTO account_activations(uid, activation_code, \
			email, first_name, last_name, country_code) VALUES(%s, %s, %s, %s, %s, %s)",
			uid, activation_code, email, first_name, last_name, country_code)

		# Send an account activation email
		self.backend.messages.send_template("auth/messages/register",
			recipients=[email], priority=100, uid=uid,
			activation_code=activation_code, email=email,
			first_name=first_name, last_name=last_name)

	def activate(self, uid, activation_code):
		res = self.db.get("DELETE FROM account_activations \
			WHERE uid = %s AND activation_code = %s AND expires_at > NOW() \
			RETURNING *", uid, activation_code)

		# Return nothing when account was not found
		if not res:
			return

		# Return the account if it has already been created
		account = self.get_by_uid(uid)
		if account:
			return account

		# Create a new account on the LDAP database
		account = self.create(uid, res.email,
			first_name=res.first_name, last_name=res.last_name,
			country_code=res.country_code)

		# Send email about account registration
		self.backend.messages.send_template("people/messages/new-account",
			recipients=["moderators@ipfire.org"], account=account)

		return account

	def create(self, uid, email, first_name, last_name, country_code=None):
		cn = "%s %s" % (first_name, last_name)

		# Account Parameters
		account = {
			"objectClass"  : [b"top", b"person", b"inetOrgPerson"],
			"mail"         : email.encode(),

			# Name
			"cn"           : cn.encode(),
			"sn"           : last_name.encode(),
			"givenName"    : first_name.encode(),
		}

		logging.info("Creating new account: %s: %s" % (uid, account))

		# Create DN
		dn = "uid=%s,ou=People,dc=ipfire,dc=org" % uid

		# Create account on LDAP
		self.accounts._authenticate()
		self.ldap.add_s(dn, ldap.modlist.addModlist(account))

		# Fetch the account
		account = self.get_by_dn(dn)

		# Optionally set country code
		if country_code:
			account.country_code = country_code

		# Return account
		return account

	# Session stuff

	def create_session(self, account, host):
		session_id = util.random_string(64)

		res = self.db.get("INSERT INTO sessions(host, uid, session_id) VALUES(%s, %s, %s) \
			RETURNING session_id, time_expires", host, account.uid, session_id)

		# Session could not be created
		if not res:
			return None, None

		logging.info("Created session %s for %s which expires %s" \
			% (res.session_id, account, res.time_expires))
		return res.session_id, res.time_expires

	def destroy_session(self, session_id, host):
		logging.info("Destroying session %s" % session_id)

		self.db.execute("DELETE FROM sessions \
			WHERE session_id = %s AND host = %s", session_id, host)

	def get_by_session(self, session_id, host):
		logging.debug("Looking up session %s" % session_id)

		res = self.db.get("SELECT uid FROM sessions WHERE session_id = %s \
			AND host = %s AND NOW() BETWEEN time_created AND time_expires",
			session_id, host)

		# Session does not exist or has expired
		if not res:
			return

		# Update the session expiration time
		self.db.execute("UPDATE sessions SET time_expires = NOW() + INTERVAL '14 days' \
			WHERE session_id = %s AND host = %s", session_id, host)

		return self.get_by_uid(res.uid)

	def cleanup(self):
		# Cleanup expired sessions
		self.db.execute("DELETE FROM sessions WHERE time_expires <= NOW()")

		# Cleanup expired account activations
		self.db.execute("DELETE FROM account_activations WHERE expires_at <= NOW()")

	# Discourse

	def decode_discourse_payload(self, payload, signature):
		# Check signature
		calculated_signature = self.sign_discourse_payload(payload)

		if not hmac.compare_digest(signature, calculated_signature):
			raise ValueError("Invalid signature: %s" % signature)

		# Decode the query string
		qs = base64.b64decode(payload).decode()

		# Parse the query string
		data = {}
		for key, val in urllib.parse.parse_qsl(qs):
			data[key] = val

		return data

	def encode_discourse_payload(self, **args):
		# Encode the arguments into an URL-formatted string
		qs = urllib.parse.urlencode(args).encode()

		# Encode into base64
		return base64.b64encode(qs).decode()

	def sign_discourse_payload(self, payload, secret=None):
		if secret is None:
			secret = self.settings.get("discourse_sso_secret")

		# Calculate a HMAC using SHA256
		h = hmac.new(secret.encode(),
			msg=payload.encode(), digestmod="sha256")

		return h.hexdigest()


class Account(Object):
	def __init__(self, backend, dn, attrs=None):
		Object.__init__(self, backend)
		self.dn = dn

		self.attributes = attrs or {}

	def __str__(self):
		if self.nickname:
			return self.nickname

		return self.name

	def __repr__(self):
		return "<%s %s>" % (self.__class__.__name__, self.dn)

	def __eq__(self, other):
		if isinstance(other, self.__class__):
			return self.dn == other.dn

	def __lt__(self, other):
		if isinstance(other, self.__class__):
			return self.name < other.name

	@property
	def ldap(self):
		return self.accounts.ldap

	def _exists(self, key):
		try:
			self.attributes[key]
		except KeyError:
			return False

		return True

	def _get(self, key):
		for value in self.attributes.get(key, []):
			yield value

	def _get_bytes(self, key, default=None):
		for value in self._get(key):
			return value

		return default

	def _get_strings(self, key):
		for value in self._get(key):
			yield value.decode()

	def _get_string(self, key, default=None):
		for value in self._get_strings(key):
			return value

		return default

	def _get_phone_numbers(self, key):
		for value in self._get_strings(key):
			yield phonenumbers.parse(value, None)

	def _get_timestamp(self, key):
		value = self._get_string(key)

		# Parse the timestamp value and returns a datetime object
		if value:
			return datetime.datetime.strptime(value, "%Y%m%d%H%M%SZ")

	def _modify(self, modlist):
		logging.debug("Modifying %s: %s" % (self.dn, modlist))

		# Authenticate before performing any write operations
		self.accounts._authenticate()

		# Run modify operation
		self.ldap.modify_s(self.dn, modlist)

		# Delete cached attributes
		self.memcache.delete("accounts:%s:attrs" % self.dn)

	def _set(self, key, values):
		current = self._get(key)

		# Don't do anything if nothing has changed
		if list(current) == values:
			return

		# Remove all old values and add all new ones
		modlist = []

		if self._exists(key):
			modlist.append((ldap.MOD_DELETE, key, None))

		# Add new values
		if values:
			modlist.append((ldap.MOD_ADD, key, values))

		# Run modify operation
		self._modify(modlist)

		# Update cache
		self.attributes.update({ key : values })

	def _set_bytes(self, key, values):
		return self._set(key, values)

	def _set_strings(self, key, values):
		return self._set(key, [e.encode() for e in values if e])

	def _set_string(self, key, value):
		return self._set_strings(key, [value,])

	def _add(self, key, values):
		modlist = [
			(ldap.MOD_ADD, key, values),
		]

		self._modify(modlist)

	def _add_strings(self, key, values):
		return self._add(key, [e.encode() for e in values])

	def _add_string(self, key, value):
		return self._add_strings(key, [value,])

	def _delete(self, key, values):
		modlist = [
			(ldap.MOD_DELETE, key, values),
		]

		self._modify(modlist)

	def _delete_strings(self, key, values):
		return self._delete(key, [e.encode() for e in values])

	def _delete_string(self, key, value):
		return self._delete_strings(key, [value,])

	@lazy_property
	def kerberos_attributes(self):
		res = self.backend.accounts._query(
			"(&(objectClass=krbPrincipal)(krbPrincipalName=%s@IPFIRE.ORG))" % self.uid,
			attrlist=[
				"krbLastSuccessfulAuth",
				"krbLastPasswordChange",
				"krbLastFailedAuth",
				"krbLoginFailedCount",
			],
			limit=1,
			search_base="cn=krb5,%s" % self.backend.accounts.search_base)

		for dn, attrs in res:
			return { key : attrs[key][0] for key in attrs }

		return {}

	@staticmethod
	def _parse_date(s):
		return datetime.datetime.strptime(s.decode(), "%Y%m%d%H%M%SZ")

	@property
	def last_successful_authentication(self):
		try:
			s = self.kerberos_attributes["krbLastSuccessfulAuth"]
		except KeyError:
			return None

		return self._parse_date(s)

	@property
	def last_failed_authentication(self):
		try:
			s = self.kerberos_attributes["krbLastFailedAuth"]
		except KeyError:
			return None

		return self._parse_date(s)

	@property
	def failed_login_count(self):
		try:
			count = self.kerberos_attributes["krbLoginFailedCount"].decode()
		except KeyError:
			return 0

		try:
			return int(count)
		except ValueError:
			return 0

	def passwd(self, password):
		"""
			Sets a new password
		"""
		# The new password must have a score of 3 or better
		quality = self.check_password_quality(password)
		if quality["score"] < 3:
			raise ValueError("Password too weak")

		self.accounts._authenticate()
		self.ldap.passwd_s(self.dn, None, password)

	def check_password(self, password):
		"""
			Bind to the server with given credentials and return
			true if password is corrent and false if not.

			Raises exceptions from the server on any other errors.
		"""
		if not password:
			return

		logging.debug("Checking credentials for %s" % self.dn)

		# Create a new LDAP connection
		ldap_uri = self.backend.settings.get("ldap_uri")
		conn = ldap.initialize(ldap_uri)

		try:
			conn.simple_bind_s(self.dn, password.encode("utf-8"))
		except ldap.INVALID_CREDENTIALS:
			logging.debug("Account credentials are invalid for %s" % self)
			return False

		logging.info("Successfully authenticated %s" % self)

		return True

	def check_password_quality(self, password):
		"""
			Passwords are passed through zxcvbn to make sure
			that they are strong enough.
		"""
		return zxcvbn.zxcvbn(password, user_inputs=(
			self.first_name, self.last_name,
		))

	def is_admin(self):
		return self.is_member_of_group("sudo")

	def is_staff(self):
		return self.is_member_of_group("staff")

	def is_moderator(self):
		return self.is_member_of_group("moderators")

	def has_shell(self):
		return "posixAccount" in self.classes

	def has_mail(self):
		return "postfixMailUser" in self.classes

	def has_sip(self):
		return "sipUser" in self.classes or "sipRoutingObject" in self.classes

	def can_be_managed_by(self, account):
		"""
			Returns True if account is allowed to manage this account
		"""
		# Admins can manage all accounts
		if account.is_admin():
			return True

		# Users can manage themselves
		return self == account

	@property
	def classes(self):
		return self._get_strings("objectClass")

	@property
	def uid(self):
		return self._get_string("uid")

	@property
	def name(self):
		return self._get_string("cn")

	# Nickname

	def get_nickname(self):
		return self._get_string("displayName")

	def set_nickname(self, nickname):
		self._set_string("displayName", nickname)

	nickname = property(get_nickname, set_nickname)

	# First Name

	def get_first_name(self):
		return self._get_string("givenName")

	def set_first_name(self, first_name):
		self._set_string("givenName", first_name)

		# Update Common Name
		self._set_string("cn", "%s %s" % (first_name, self.last_name))

	first_name = property(get_first_name, set_first_name)

	# Last Name

	def get_last_name(self):
		return self._get_string("sn")

	def set_last_name(self, last_name):
		self._set_string("sn", last_name)

		# Update Common Name
		self._set_string("cn", "%s %s" % (self.first_name, last_name))

	last_name = property(get_last_name, set_last_name)

	@lazy_property
	def groups(self):
		return self.backend.groups._get_groups("(| \
			(&(objectClass=groupOfNames)(member=%s)) \
			(&(objectClass=posixGroup)(memberUid=%s)) \
		)" % (self.dn, self.uid))

	def is_member_of_group(self, gid):
		"""
			Returns True if this account is a member of this group
		"""
		return gid in (g.gid for g in self.groups)

	# Created/Modified at

	@property
	def created_at(self):
		return self._get_timestamp("createTimestamp")

	@property
	def modified_at(self):
		return self._get_timestamp("modifyTimestamp")

	# Address

	@property
	def address(self):
		address = []

		if self.street:
			address += self.street.splitlines()

		if self.postal_code and self.city:
			if self.country_code in ("AT", "DE"):
				address.append("%s %s" % (self.postal_code, self.city))
			else:
				address.append("%s, %s" % (self.city, self.postal_code))
		else:
			address.append(self.city or self.postal_code)

		if self.country_name:
			address.append(self.country_name)

		return address

	def get_street(self):
		return self._get_string("street") or self._get_string("homePostalAddress")

	def set_street(self, street):
		self._set_string("street", street)

	street = property(get_street, set_street)

	def get_city(self):
		return self._get_string("l") or ""

	def set_city(self, city):
		self._set_string("l", city)

	city = property(get_city, set_city)

	def get_postal_code(self):
		return self._get_string("postalCode") or ""

	def set_postal_code(self, postal_code):
		self._set_string("postalCode", postal_code)

	postal_code = property(get_postal_code, set_postal_code)

	# XXX This should be c
	def get_country_code(self):
		return self._get_string("st")

	def set_country_code(self, country_code):
		self._set_string("st", country_code)

	country_code = property(get_country_code, set_country_code)

	@property
	def country_name(self):
		if self.country_code:
			return countries.get_name(self.country_code)

	@property
	def email(self):
		return self._get_string("mail")

	# Mail Routing Address

	def get_mail_routing_address(self):
		return self._get_string("mailRoutingAddress", None)

	def set_mail_routing_address(self, address):
		self._set_string("mailRoutingAddress", address or None)

	mail_routing_address = property(get_mail_routing_address, set_mail_routing_address)

	@property
	def sip_id(self):
		if "sipUser" in self.classes:
			return self._get_string("sipAuthenticationUser")

		if "sipRoutingObject" in self.classes:
			return self._get_string("sipLocalAddress")

	@property
	def sip_password(self):
		return self._get_string("sipPassword")

	@staticmethod
	def _generate_sip_password():
		return util.random_string(8)

	@property
	def sip_url(self):
		return "%s@ipfire.org" % self.sip_id

	def uses_sip_forwarding(self):
		if self.sip_routing_address:
			return True

		return False

	# SIP Routing

	def get_sip_routing_address(self):
		if "sipRoutingObject" in self.classes:
			return self._get_string("sipRoutingAddress")

	def set_sip_routing_address(self, address):
		if not address:
			address = None

		# Don't do anything if nothing has changed
		if self.get_sip_routing_address() == address:
			return

		if address:
			# This is no longer a SIP user any more
			try:
				self._modify([
					(ldap.MOD_DELETE, "objectClass", b"sipUser"),
					(ldap.MOD_DELETE, "sipAuthenticationUser", None),
					(ldap.MOD_DELETE, "sipPassword", None),
				])
			except ldap.NO_SUCH_ATTRIBUTE:
				pass

			# Set new routing object
			try:
				self._modify([
					(ldap.MOD_ADD, "objectClass", b"sipRoutingObject"),
					(ldap.MOD_ADD, "sipLocalAddress", self.sip_id.encode()),
					(ldap.MOD_ADD, "sipRoutingAddress", address.encode()),
				])

			# If this is a change, we cannot add this again
			except ldap.TYPE_OR_VALUE_EXISTS:
				self._set_string("sipRoutingAddress", address)
		else:
			try:
				self._modify([
					(ldap.MOD_DELETE, "objectClass", b"sipRoutingObject"),
					(ldap.MOD_DELETE, "sipLocalAddress", None),
					(ldap.MOD_DELETE, "sipRoutingAddress", None),
				])
			except ldap.NO_SUCH_ATTRIBUTE:
				pass

			self._modify([
				(ldap.MOD_ADD, "objectClass", b"sipUser"),
				(ldap.MOD_ADD, "sipAuthenticationUser", self.sip_id.encode()),
				(ldap.MOD_ADD, "sipPassword", self._generate_sip_password().encode()),
			])

		# XXX Cache is invalid here

	sip_routing_address = property(get_sip_routing_address, set_sip_routing_address)

	@lazy_property
	def sip_registrations(self):
		sip_registrations = []

		for reg in self.backend.talk.freeswitch.get_sip_registrations(self.sip_url):
			reg.account = self

			sip_registrations.append(reg)

		return sip_registrations

	@lazy_property
	def sip_channels(self):
		return self.backend.talk.freeswitch.get_sip_channels(self)

	def get_cdr(self, date=None, limit=None):
		return self.backend.talk.freeswitch.get_cdr_by_account(self, date=date, limit=limit)

	# Phone Numbers

	@lazy_property
	def phone_number(self):
		"""
			Returns the IPFire phone number
		"""
		if self.sip_id:
			return phonenumbers.parse("+4923636035%s" % self.sip_id)

	@lazy_property
	def fax_number(self):
		if self.sip_id:
			return phonenumbers.parse("+49236360359%s" % self.sip_id)

	def get_phone_numbers(self):
		ret = []

		for field in ("telephoneNumber", "homePhone", "mobile"):
			for number in self._get_phone_numbers(field):
				ret.append(number)

		return ret

	def set_phone_numbers(self, phone_numbers):
		# Sort phone numbers by landline and mobile
		_landline_numbers = []
		_mobile_numbers = []

		for number in phone_numbers:
			try:
				number = phonenumbers.parse(number, None)
			except phonenumbers.phonenumberutil.NumberParseException:
				continue

			# Convert to string (in E.164 format)
			s = phonenumbers.format_number(number, phonenumbers.PhoneNumberFormat.E164)

			# Separate mobile numbers
			if phonenumbers.number_type(number) == phonenumbers.PhoneNumberType.MOBILE:
				_mobile_numbers.append(s)
			else:
				_landline_numbers.append(s)

		# Save
		self._set_strings("telephoneNumber", _landline_numbers)
		self._set_strings("mobile", _mobile_numbers)

	phone_numbers = property(get_phone_numbers, set_phone_numbers)

	@property
	def _all_telephone_numbers(self):
		ret = [ self.sip_id, ]

		if self.phone_number:
			s = phonenumbers.format_number(self.phone_number, phonenumbers.PhoneNumberFormat.E164)
			ret.append(s)

		for number in self.phone_numbers:
			s = phonenumbers.format_number(number, phonenumbers.PhoneNumberFormat.E164)
			ret.append(s)

		return ret

	def has_avatar(self):
		has_avatar = self.memcache.get("accounts:%s:has-avatar" % self.uid)
		if has_avatar is None:
			has_avatar = True if self.get_avatar() else False

			# Cache avatar status for up to 24 hours
			self.memcache.set("accounts:%s:has-avatar" % self.uid, has_avatar, 3600 * 24)

		return has_avatar

	def avatar_url(self, size=None):
		url = "https://people.ipfire.org/users/%s.jpg" % self.uid

		if size:
			url += "?size=%s" % size

		return url

	def get_avatar(self, size=None):
		photo = self._get_bytes("jpegPhoto")

		# Exit if no avatar is available
		if not photo:
			return

		# Return the raw image if no size was requested
		if size is None:
			return photo

		# Try to retrieve something from the cache
		avatar = self.memcache.get("accounts:%s:avatar:%s" % (self.dn, size))
		if avatar:
			return avatar

		# Generate a new thumbnail
		avatar = util.generate_thumbnail(photo, size, square=True)

		# Save to cache for 15m
		self.memcache.set("accounts:%s:avatar:%s" % (self.dn, size), avatar, 900)

		return avatar

	def upload_avatar(self, avatar):
		self._set("jpegPhoto", avatar)

		# Delete cached avatar status
		self.memcache.delete("accounts:%s:has-avatar" % self.uid)


class StopForumSpam(Object):
	def init(self, uid, email, address):
		self.uid, self.email, self.address = uid, email, address

	@tornado.gen.coroutine
	def send_request(self, **kwargs):
		arguments = {
			"json" : "1",
		}
		arguments.update(kwargs)

		# Create request
		request = tornado.httpclient.HTTPRequest(
			"https://api.stopforumspam.org/api", method="POST")
		request.body = urllib.parse.urlencode(arguments)

		# Send the request
		response = yield self.backend.http_client.fetch(request)

		# Decode the JSON response
		return json.loads(response.body.decode())

	@tornado.gen.coroutine
	def check_address(self):
		response = yield self.send_request(ip=self.address)

		try:
			confidence = response["ip"]["confidence"]
		except KeyError:
			confidence = 100

		logging.debug("Confidence for %s: %s" % (self.address, confidence))

		return confidence

	@tornado.gen.coroutine
	def check_username(self):
		response = yield self.send_request(username=self.uid)

		try:
			confidence = response["username"]["confidence"]
		except KeyError:
			confidence = 100

		logging.debug("Confidence for %s: %s" % (self.uid, confidence))

		return confidence

	@tornado.gen.coroutine
	def check_email(self):
		response = yield self.send_request(email=self.email)

		try:
			confidence = response["email"]["confidence"]
		except KeyError:
			confidence = 100

		logging.debug("Confidence for %s: %s" % (self.email, confidence))

		return confidence

	@tornado.gen.coroutine
	def check(self, threshold=95):
		"""
			This function tries to detect if we have a spammer.

			To honour the privacy of our users, we only send the IP
			address and username and if those are on the database, we
			will send the email address as well.
		"""
		confidences = yield [self.check_address(), self.check_username()]

		if any((c < threshold for c in confidences)):
			confidences += yield [self.check_email()]

		# Build a score based on the lowest confidence
		return 100 - min(confidences)


class Groups(Object):
	hidden_groups = (
		"cn=LDAP Read Only,ou=Group,dc=ipfire,dc=org",
		"cn=LDAP Read Write,ou=Group,dc=ipfire,dc=org",
		"cn=sudo,ou=Group,dc=ipfire,dc=org",

		# Everyone is a member of people
		"cn=people,ou=Group,dc=ipfire,dc=org",
	)

	@property
	def search_base(self):
		return "ou=Group,%s" % self.backend.accounts.search_base

	def _query(self, *args, **kwargs):
		kwargs.update({
			"search_base" : self.backend.groups.search_base,
		})

		return self.backend.accounts._query(*args, **kwargs)

	def __iter__(self):
		groups = self.get_all()

		return iter(groups)

	def _get_groups(self, query, **kwargs):
		res = self._query(query, **kwargs)

		groups = []
		for dn, attrs in res:
			# Skip any hidden groups
			if dn in self.hidden_groups:
				continue

			g = Group(self.backend, dn, attrs)
			groups.append(g)

		return sorted(groups)

	def _get_group(self, query, **kwargs):
		kwargs.update({
			"limit" : 1,
		})

		groups = self._get_groups(query, **kwargs)
		if groups:
			return groups[0]

	def get_all(self):
		return self._get_groups(
			"(|(objectClass=posixGroup)(objectClass=groupOfNames))",
		)

	def get_by_gid(self, gid):
		return self._get_group(
			"(&(|(objectClass=posixGroup)(objectClass=groupOfNames))(cn=%s))" % gid,
		)


class Group(Object):
	def init(self, dn, attrs=None):
		self.dn = dn

		self.attributes = attrs or {}

	def __repr__(self):
		if self.description:
			return "<%s %s (%s)>" % (
				self.__class__.__name__,
				self.gid,
				self.description,
			)

		return "<%s %s>" % (self.__class__.__name__, self.gid)

	def __str__(self):
		return self.description or self.gid

	def __eq__(self, other):
		if isinstance(other, self.__class__):
			return self.gid == other.gid

	def __lt__(self, other):
		if isinstance(other, self.__class__):
			return (self.description or self.gid) < (other.description or other.gid)

	def __bool__(self):
		return True

	def __len__(self):
		"""
			Returns the number of members in this group
		"""
		l = 0

		for attr in ("member", "memberUid"):
			a = self.attributes.get(attr, None)
			if a:
				l += len(a)

		return l

	def __iter__(self):
		return iter(self.members)

	@property
	def gid(self):
		try:
			gid = self.attributes["cn"][0]
		except KeyError:
			return None

		return gid.decode()

	@property
	def description(self):
		try:
			description = self.attributes["description"][0]
		except KeyError:
			return None

		return description.decode()

	@property
	def email(self):
		try:
			email = self.attributes["mail"][0]
		except KeyError:
			return None

		return email.decode()

	@lazy_property
	def members(self):
		members = []

		# Get all members by DN
		for dn in self.attributes.get("member", []):
			member = self.backend.accounts.get_by_dn(dn.decode())
			if member:
				members.append(member)

		# Get all meembers by UID
		for uid in self.attributes.get("memberUid", []):
			member = self.backend.accounts.get_by_uid(uid.decode())
			if member:
				members.append(member)

		return sorted(members)

if __name__ == "__main__":
	a = Accounts()

	print(a.list())