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# Contributors Listed Below - COPYRIGHT 2016
# [+] International Business Machines Corp.
#
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied. See the License for the specific language governing
# permissions and limitations under the License.
import os
import sys
import dbus
import dbus.exceptions
import json
from xml.etree import ElementTree
from bottle import Bottle, abort, request, response, JSONPlugin, HTTPError
from bottle import static_file
import obmc.utils.misc
from obmc.dbuslib.introspection import IntrospectionNodeParser
import obmc.mapper
import spwd
import grp
import crypt
import tempfile
import re
import mimetypes
have_wsock = True
try:
from geventwebsocket import WebSocketError
except ImportError:
have_wsock = False
if have_wsock:
from dbus.mainloop.glib import DBusGMainLoop
DBusGMainLoop(set_as_default=True)
# TODO: openbmc/openbmc#2994 remove python 2 support
try: # python 2
import gobject
except ImportError: # python 3
from gi.repository import GObject as gobject
import gevent
from gevent import socket
from gevent import Greenlet
DBUS_UNKNOWN_INTERFACE = 'org.freedesktop.DBus.Error.UnknownInterface'
DBUS_UNKNOWN_METHOD = 'org.freedesktop.DBus.Error.UnknownMethod'
DBUS_PROPERTY_READONLY = 'org.freedesktop.DBus.Error.PropertyReadOnly'
DBUS_INVALID_ARGS = 'org.freedesktop.DBus.Error.InvalidArgs'
DBUS_TYPE_ERROR = 'org.freedesktop.DBus.Python.TypeError'
DELETE_IFACE = 'xyz.openbmc_project.Object.Delete'
SOFTWARE_PATH = '/xyz/openbmc_project/software'
WEBSOCKET_TIMEOUT = 45
_4034_msg = "The specified %s cannot be %s: '%s'"
www_base_path = '/usr/share/www/'
def valid_user(session, *a, **kw):
''' Authorization plugin callback that checks
that the user is logged in. '''
if session is None:
abort(401, 'Login required')
def get_type_signature_by_introspection(bus, service, object_path,
property_name):
obj = bus.get_object(service, object_path)
iface = dbus.Interface(obj, 'org.freedesktop.DBus.Introspectable')
xml_string = iface.Introspect()
for child in ElementTree.fromstring(xml_string):
# Iterate over each interfaces's properties to find
# matching property_name, and return its signature string
if child.tag == 'interface':
for i in child.iter():
if ('name' in i.attrib) and \
(i.attrib['name'] == property_name):
type_signature = i.attrib['type']
return type_signature
def get_method_signature(bus, service, object_path, interface, method):
obj = bus.get_object(service, object_path)
iface = dbus.Interface(obj, 'org.freedesktop.DBus.Introspectable')
xml_string = iface.Introspect()
arglist = []
root = ElementTree.fromstring(xml_string)
for dbus_intf in root.findall('interface'):
if (dbus_intf.get('name') == interface):
for dbus_method in dbus_intf.findall('method'):
if(dbus_method.get('name') == method):
for arg in dbus_method.findall('arg'):
arglist.append(arg.get('type'))
return arglist
def split_struct_signature(signature):
struct_regex = r'(b|y|n|i|x|q|u|t|d|s|a\(.+?\)|\(.+?\))|a\{.+?\}+?'
struct_matches = re.findall(struct_regex, signature)
return struct_matches
def convert_type(signature, value):
# Basic Types
converted_value = None
converted_container = None
# TODO: openbmc/openbmc#2994 remove python 2 support
try: # python 2
basic_types = {'b': bool, 'y': dbus.Byte, 'n': dbus.Int16, 'i': int,
'x': long, 'q': dbus.UInt16, 'u': dbus.UInt32,
't': dbus.UInt64, 'd': float, 's': str}
except NameError: # python 3
basic_types = {'b': bool, 'y': dbus.Byte, 'n': dbus.Int16, 'i': int,
'x': int, 'q': dbus.UInt16, 'u': dbus.UInt32,
't': dbus.UInt64, 'd': float, 's': str}
array_matches = re.match(r'a\((\S+)\)', signature)
struct_matches = re.match(r'\((\S+)\)', signature)
dictionary_matches = re.match(r'a{(\S+)}', signature)
if signature in basic_types:
converted_value = basic_types[signature](value)
return converted_value
# Array
if array_matches:
element_type = array_matches.group(1)
converted_container = list()
# Test if value is a list
# to avoid iterating over each character in a string.
# Iterate over each item and convert type
if isinstance(value, list):
for i in value:
converted_element = convert_type(element_type, i)
converted_container.append(converted_element)
# Convert non-sequence to expected type, and append to list
else:
converted_element = convert_type(element_type, value)
converted_container.append(converted_element)
return converted_container
# Struct
if struct_matches:
element_types = struct_matches.group(1)
split_element_types = split_struct_signature(element_types)
converted_container = list()
# Test if value is a list
if isinstance(value, list):
for index, val in enumerate(value):
converted_element = convert_type(split_element_types[index],
value[index])
converted_container.append(converted_element)
else:
converted_element = convert_type(element_types, value)
converted_container.append(converted_element)
return tuple(converted_container)
# Dictionary
if dictionary_matches:
element_types = dictionary_matches.group(1)
split_element_types = split_struct_signature(element_types)
converted_container = dict()
# Convert each element of dict
for key, val in value.items():
converted_key = convert_type(split_element_types[0], key)
converted_val = convert_type(split_element_types[1], val)
converted_container[converted_key] = converted_val
return converted_container
def send_ws_ping(wsock, timeout) :
# Most webservers close websockets after 60 seconds of
# inactivity. Make sure to send a ping before that.
payload = "ping"
# the ping payload can be anything, the receiver has to just
# return the same back.
while True:
gevent.sleep(timeout)
try:
if wsock:
wsock.send_frame(payload, wsock.OPCODE_PING)
except Exception as e:
wsock.close()
return
class UserInGroup:
''' Authorization plugin callback that checks that the user is logged in
and a member of a group. '''
def __init__(self, group):
self.group = group
def __call__(self, session, *a, **kw):
valid_user(session, *a, **kw)
res = False
try:
res = session['user'] in grp.getgrnam(self.group)[3]
except KeyError:
pass
if not res:
abort(403, 'Insufficient access')
class RouteHandler(object):
_require_auth = obmc.utils.misc.makelist(valid_user)
_enable_cors = True
def __init__(self, app, bus, verbs, rules, content_type=''):
self.app = app
self.bus = bus
self.mapper = obmc.mapper.Mapper(bus)
self._verbs = obmc.utils.misc.makelist(verbs)
self._rules = rules
self._content_type = content_type
if 'GET' in self._verbs:
self._verbs = list(set(self._verbs + ['HEAD']))
if 'OPTIONS' not in self._verbs:
self._verbs.append('OPTIONS')
def _setup(self, **kw):
request.route_data = {}
if request.method in self._verbs:
if request.method != 'OPTIONS':
return self.setup(**kw)
# Javascript implementations will not send credentials
# with an OPTIONS request. Don't help malicious clients
# by checking the path here and returning a 404 if the
# path doesn't exist.
return None
# Return 405
raise HTTPError(
405, "Method not allowed.", Allow=','.join(self._verbs))
def __call__(self, **kw):
return getattr(self, 'do_' + request.method.lower())(**kw)
def do_head(self, **kw):
return self.do_get(**kw)
def do_options(self, **kw):
for v in self._verbs:
response.set_header(
'Allow',
','.join(self._verbs))
return None
def install(self):
self.app.route(
self._rules, callback=self,
method=['OPTIONS', 'GET', 'PUT', 'PATCH', 'POST', 'DELETE'])
@staticmethod
def try_mapper_call(f, callback=None, **kw):
try:
return f(**kw)
except dbus.exceptions.DBusException as e:
if e.get_dbus_name() == \
'org.freedesktop.DBus.Error.ObjectPathInUse':
abort(503, str(e))
if e.get_dbus_name() != obmc.mapper.MAPPER_NOT_FOUND:
raise
if callback is None:
def callback(e, **kw):
abort(404, str(e))
callback(e, **kw)
@staticmethod
def try_properties_interface(f, *a):
try:
return f(*a)
except dbus.exceptions.DBusException as e:
if DBUS_UNKNOWN_INTERFACE in e.get_dbus_name():
# interface doesn't have any properties
return None
if DBUS_UNKNOWN_METHOD == e.get_dbus_name():
# properties interface not implemented at all
return None
raise
class DirectoryHandler(RouteHandler):
verbs = 'GET'
rules = '<path:path>/'
suppress_logging = True
def __init__(self, app, bus):
super(DirectoryHandler, self).__init__(
app, bus, self.verbs, self.rules)
def find(self, path='/'):
return self.try_mapper_call(
self.mapper.get_subtree_paths, path=path, depth=1)
def setup(self, path='/'):
request.route_data['map'] = self.find(path)
def do_get(self, path='/'):
return request.route_data['map']
class ListNamesHandler(RouteHandler):
verbs = 'GET'
rules = ['/list', '<path:path>/list']
suppress_logging = True
def __init__(self, app, bus):
super(ListNamesHandler, self).__init__(
app, bus, self.verbs, self.rules)
def find(self, path='/'):
return list(self.try_mapper_call(
self.mapper.get_subtree, path=path).keys())
def setup(self, path='/'):
request.route_data['map'] = self.find(path)
def do_get(self, path='/'):
return request.route_data['map']
class ListHandler(RouteHandler):
verbs = 'GET'
rules = ['/enumerate', '<path:path>/enumerate']
suppress_logging = True
def __init__(self, app, bus):
super(ListHandler, self).__init__(
app, bus, self.verbs, self.rules)
def find(self, path='/'):
return self.try_mapper_call(
self.mapper.get_subtree, path=path)
def setup(self, path='/'):
request.route_data['map'] = self.find(path)
def do_get(self, path='/'):
return {x: y for x, y in self.mapper.enumerate_subtree(
path,
mapper_data=request.route_data['map']).dataitems()}
class MethodHandler(RouteHandler):
verbs = 'POST'
rules = '<path:path>/action/<method>'
request_type = list
content_type = 'application/json'
def __init__(self, app, bus):
super(MethodHandler, self).__init__(
app, bus, self.verbs, self.rules, self.content_type)
self.service = ''
self.interface = ''
def find(self, path, method):
method_list = []
buses = self.try_mapper_call(
self.mapper.get_object, path=path)
for items in buses.items():
m = self.find_method_on_bus(path, method, *items)
if m:
method_list.append(m)
if method_list:
return method_list
abort(404, _4034_msg % ('method', 'found', method))
def setup(self, path, method):
request.route_data['map'] = self.find(path, method)
def do_post(self, path, method, retry=True):
try:
args = []
if request.parameter_list:
args = request.parameter_list
# To see if the return type is capable of being merged
if len(request.route_data['map']) > 1:
results = None
for item in request.route_data['map']:
tmp = item(*args)
if not results:
if tmp is not None:
results = type(tmp)()
if isinstance(results, dict):
results = results.update(tmp)
elif isinstance(results, list):
results = results + tmp
elif isinstance(results, type(None)):
results = None
else:
abort(501, 'Don\'t know how to merge method call '
'results of {}'.format(type(tmp)))
return results
# There is only one method
return request.route_data['map'][0](*args)
except dbus.exceptions.DBusException as e:
paramlist = []
if e.get_dbus_name() == DBUS_INVALID_ARGS and retry:
signature_list = get_method_signature(self.bus, self.service,
path, self.interface,
method)
if not signature_list:
abort(400, "Failed to get method signature: %s" % str(e))
if len(signature_list) != len(request.parameter_list):
abort(400, "Invalid number of args")
converted_value = None
try:
for index, expected_type in enumerate(signature_list):
value = request.parameter_list[index]
converted_value = convert_type(expected_type, value)
paramlist.append(converted_value)
request.parameter_list = paramlist
self.do_post(path, method, False)
return
except Exception as ex:
abort(400, "Bad Request/Invalid Args given")
abort(400, str(e))
if e.get_dbus_name() == DBUS_TYPE_ERROR:
abort(400, str(e))
raise
@staticmethod
def find_method_in_interface(method, obj, interface, methods):
if methods is None:
return None
method = obmc.utils.misc.find_case_insensitive(method, list(methods.keys()))
if method is not None:
iface = dbus.Interface(obj, interface)
return iface.get_dbus_method(method)
def find_method_on_bus(self, path, method, bus, interfaces):
obj = self.bus.get_object(bus, path, introspect=False)
iface = dbus.Interface(obj, dbus.INTROSPECTABLE_IFACE)
data = iface.Introspect()
parser = IntrospectionNodeParser(
ElementTree.fromstring(data),
intf_match=lambda x: x in interfaces)
for x, y in parser.get_interfaces().items():
m = self.find_method_in_interface(
method, obj, x, y.get('method'))
if m:
self.service = bus
self.interface = x
return m
class PropertyHandler(RouteHandler):
verbs = ['PUT', 'GET']
rules = '<path:path>/attr/<prop>'
content_type = 'application/json'
def __init__(self, app, bus):
super(PropertyHandler, self).__init__(
app, bus, self.verbs, self.rules, self.content_type)
def find(self, path, prop):
self.app.instance_handler.setup(path)
obj = self.app.instance_handler.do_get(path)
real_name = obmc.utils.misc.find_case_insensitive(
prop, list(obj.keys()))
if not real_name:
if request.method == 'PUT':
abort(403, _4034_msg % ('property', 'created', prop))
else:
abort(404, _4034_msg % ('property', 'found', prop))
return real_name, {path: obj}
def setup(self, path, prop):
name, obj = self.find(path, prop)
request.route_data['obj'] = obj
request.route_data['name'] = name
def do_get(self, path, prop):
name = request.route_data['name']
return request.route_data['obj'][path][name]
def do_put(self, path, prop, value=None, retry=True):
if value is None:
value = request.parameter_list
prop, iface, properties_iface = self.get_host_interface(
path, prop, request.route_data['map'][path])
try:
properties_iface.Set(iface, prop, value)
except ValueError as e:
abort(400, str(e))
except dbus.exceptions.DBusException as e:
if e.get_dbus_name() == DBUS_PROPERTY_READONLY:
abort(403, str(e))
if e.get_dbus_name() == DBUS_INVALID_ARGS and retry:
bus_name = properties_iface.bus_name
expected_type = get_type_signature_by_introspection(self.bus,
bus_name,
path,
prop)
if not expected_type:
abort(403, "Failed to get expected type: %s" % str(e))
converted_value = None
try:
converted_value = convert_type(expected_type, value)
except Exception as ex:
abort(403, "Failed to convert %s to type %s" %
(value, expected_type))
try:
self.do_put(path, prop, converted_value, False)
return
except Exception as ex:
abort(403, str(ex))
abort(403, str(e))
raise
def get_host_interface(self, path, prop, bus_info):
for bus, interfaces in bus_info.items():
obj = self.bus.get_object(bus, path, introspect=True)
properties_iface = dbus.Interface(
obj, dbus_interface=dbus.PROPERTIES_IFACE)
info = self.get_host_interface_on_bus(
path, prop, properties_iface, bus, interfaces)
if info is not None:
prop, iface = info
return prop, iface, properties_iface
def get_host_interface_on_bus(self, path, prop, iface, bus, interfaces):
for i in interfaces:
properties = self.try_properties_interface(iface.GetAll, i)
if not properties:
continue
match = obmc.utils.misc.find_case_insensitive(
prop, list(properties.keys()))
if match is None:
continue
prop = match
return prop, i
class SchemaHandler(RouteHandler):
verbs = ['GET']
rules = '<path:path>/schema'
suppress_logging = True
def __init__(self, app, bus):
super(SchemaHandler, self).__init__(
app, bus, self.verbs, self.rules)
def find(self, path):
return self.try_mapper_call(
self.mapper.get_object,
path=path)
def setup(self, path):
request.route_data['map'] = self.find(path)
def do_get(self, path):
schema = {}
for x in request.route_data['map'].keys():
obj = self.bus.get_object(x, path, introspect=False)
iface = dbus.Interface(obj, dbus.INTROSPECTABLE_IFACE)
data = iface.Introspect()
parser = IntrospectionNodeParser(
ElementTree.fromstring(data))
for x, y in parser.get_interfaces().items():
schema[x] = y
return schema
class InstanceHandler(RouteHandler):
verbs = ['GET', 'PUT', 'DELETE']
rules = '<path:path>'
request_type = dict
def __init__(self, app, bus):
super(InstanceHandler, self).__init__(
app, bus, self.verbs, self.rules)
def find(self, path, callback=None):
return {path: self.try_mapper_call(
self.mapper.get_object,
callback,
path=path)}
def setup(self, path):
callback = None
if request.method == 'PUT':
def callback(e, **kw):
abort(403, _4034_msg % ('resource', 'created', path))
if request.route_data.get('map') is None:
request.route_data['map'] = self.find(path, callback)
def do_get(self, path):
return self.mapper.enumerate_object(
path,
mapper_data=request.route_data['map'])
def do_put(self, path):
# make sure all properties exist in the request
obj = set(self.do_get(path).keys())
req = set(request.parameter_list.keys())
diff = list(obj.difference(req))
if diff:
abort(403, _4034_msg % (
'resource', 'removed', '%s/attr/%s' % (path, diff[0])))
diff = list(req.difference(obj))
if diff:
abort(403, _4034_msg % (
'resource', 'created', '%s/attr/%s' % (path, diff[0])))
for p, v in request.parameter_list.items():
self.app.property_handler.do_put(
path, p, v)
def do_delete(self, path):
deleted = False
for bus, interfaces in request.route_data['map'][path].items():
if self.bus_has_delete(interfaces):
self.delete_on_bus(path, bus)
deleted = True
#It's OK if some objects didn't have a Delete, but not all
if not deleted:
abort(403, _4034_msg % ('resource', 'removed', path))
def bus_has_delete(self, interfaces):
return DELETE_IFACE in interfaces
def delete_on_bus(self, path, bus):
obj = self.bus.get_object(bus, path, introspect=False)
delete_iface = dbus.Interface(
obj, dbus_interface=DELETE_IFACE)
delete_iface.Delete()
class SessionHandler(MethodHandler):
''' Handles the /login and /logout routes, manages
server side session store and session cookies. '''
rules = ['/login', '/logout']
login_str = "User '%s' logged %s"
bad_passwd_str = "Invalid username or password"
no_user_str = "No user logged in"
bad_json_str = "Expecting request format { 'data': " \
"[<username>, <password>] }, got '%s'"
bmc_not_ready_str = "BMC is not ready (booting)"
_require_auth = None
MAX_SESSIONS = 16
BMCSTATE_IFACE = 'xyz.openbmc_project.State.BMC'
BMCSTATE_PATH = '/xyz/openbmc_project/state/bmc0'
BMCSTATE_PROPERTY = 'CurrentBMCState'
BMCSTATE_READY = 'xyz.openbmc_project.State.BMC.BMCState.Ready'
suppress_json_logging = True
def __init__(self, app, bus):
super(SessionHandler, self).__init__(
app, bus)
self.hmac_key = os.urandom(128)
self.session_store = []
@staticmethod
def authenticate(username, clear):
try:
encoded = spwd.getspnam(username)[1]
return encoded == crypt.crypt(clear, encoded)
except KeyError:
return False
def invalidate_session(self, session):
try:
self.session_store.remove(session)
except ValueError:
pass
def new_session(self):
sid = os.urandom(32)
if self.MAX_SESSIONS <= len(self.session_store):
self.session_store.pop()
self.session_store.insert(0, {'sid': sid})
return self.session_store[0]
def get_session(self, sid):
sids = [x['sid'] for x in self.session_store]
try:
return self.session_store[sids.index(sid)]
except ValueError:
return None
def get_session_from_cookie(self):
return self.get_session(
request.get_cookie(
'sid', secret=self.hmac_key))
def do_post(self, **kw):
if request.path == '/login':
return self.do_login(**kw)
else:
return self.do_logout(**kw)
def do_logout(self, **kw):
session = self.get_session_from_cookie()
if session is not None:
user = session['user']
self.invalidate_session(session)
response.delete_cookie('sid')
return self.login_str % (user, 'out')
return self.no_user_str
def do_login(self, **kw):
if len(request.parameter_list) != 2:
abort(400, self.bad_json_str % (request.json))
if not self.authenticate(*request.parameter_list):
abort(401, self.bad_passwd_str)
force = False
try:
force = request.json.get('force')
except (ValueError, AttributeError, KeyError, TypeError):
force = False
if not force and not self.is_bmc_ready():
abort(503, self.bmc_not_ready_str)
user = request.parameter_list[0]
session = self.new_session()
session['user'] = user
response.set_cookie(
'sid', session['sid'], secret=self.hmac_key,
secure=True,
httponly=True)
return self.login_str % (user, 'in')
def is_bmc_ready(self):
if not self.app.with_bmc_check:
return True
try:
obj = self.bus.get_object(self.BMCSTATE_IFACE, self.BMCSTATE_PATH)
iface = dbus.Interface(obj, dbus.PROPERTIES_IFACE)
state = iface.Get(self.BMCSTATE_IFACE, self.BMCSTATE_PROPERTY)
if state == self.BMCSTATE_READY:
return True
except dbus.exceptions.DBusException:
pass
return False
def find(self, **kw):
pass
def setup(self, **kw):
pass
class ImageUploadUtils:
''' Provides common utils for image upload. '''
file_loc = '/tmp/images'
file_prefix = 'img'
file_suffix = ''
signal = None
@classmethod
def do_upload(cls, filename=''):
def cleanup():
os.close(handle)
if cls.signal:
cls.signal.remove()
cls.signal = None
def signal_callback(path, a, **kw):
# Just interested on the first Version interface created which is
# triggered when the file is uploaded. This helps avoid getting the
# wrong information for multiple upload requests in a row.
if "xyz.openbmc_project.Software.Version" in a and \
"xyz.openbmc_project.Software.Activation" not in a:
paths.append(path)
while cls.signal:
# Serialize uploads by waiting for the signal to be cleared.
# This makes it easier to ensure that the version information
# is the right one instead of the data from another upload request.
gevent.sleep(1)
if not os.path.exists(cls.file_loc):
abort(500, "Error Directory not found")
paths = []
bus = dbus.SystemBus()
cls.signal = bus.add_signal_receiver(
signal_callback,
dbus_interface=dbus.BUS_DAEMON_IFACE + '.ObjectManager',
signal_name='InterfacesAdded',
path=SOFTWARE_PATH)
if not filename:
handle, filename = tempfile.mkstemp(cls.file_suffix,
cls.file_prefix, cls.file_loc)
else:
filename = os.path.join(cls.file_loc, filename)
handle = os.open(filename, os.O_WRONLY | os.O_CREAT)
try:
file_contents = request.body.read()
request.body.close()
os.write(handle, file_contents)
# Close file after writing, the image manager process watches for
# the close event to know the upload is complete.
os.close(handle)
except (IOError, ValueError) as e:
cleanup()
abort(400, str(e))
except Exception:
cleanup()
abort(400, "Unexpected Error")
loop = gobject.MainLoop()
gcontext = loop.get_context()
count = 0
version_id = ''
while loop is not None:
try:
if gcontext.pending():
gcontext.iteration()
if not paths:
gevent.sleep(1)
else:
version_id = os.path.basename(paths.pop())
break
count += 1
if count == 10:
break
except Exception:
break
cls.signal.remove()
cls.signal = None
if version_id:
return version_id
else:
abort(400, "Version already exists or failed to be extracted")
class ImagePostHandler(RouteHandler):
''' Handles the /upload/image route. '''
verbs = ['POST']
rules = ['/upload/image']
content_type = 'application/octet-stream'
def __init__(self, app, bus):
super(ImagePostHandler, self).__init__(
app, bus, self.verbs, self.rules, self.content_type)
def do_post(self, filename=''):
return ImageUploadUtils.do_upload()
def find(self, **kw):
pass
def setup(self, **kw):
pass
class CertificateHandler:
file_suffix = '.pem'
file_prefix = 'cert_'
CERT_PATH = '/xyz/openbmc_project/certs'
CERT_IFACE = 'xyz.openbmc_project.Certs.Install'
def __init__(self, route_handler, cert_type, service):
if not service:
abort(500, "Missing service")
if not cert_type:
abort(500, "Missing certificate type")
bus = dbus.SystemBus()
certPath = self.CERT_PATH + "/" + cert_type + "/" + service
intfs = route_handler.try_mapper_call(
route_handler.mapper.get_object, path=certPath)
for busName,intf in intfs.items():
if self.CERT_IFACE in intf:
self.obj = bus.get_object(busName, certPath)
return
abort(404, "Path not found")
def do_upload(self):
def cleanup():
if os.path.exists(temp.name):
os.remove(temp.name)
with tempfile.NamedTemporaryFile(
suffix=self.file_suffix,
prefix=self.file_prefix,
delete=False) as temp:
try:
file_contents = request.body.read()
request.body.close()
temp.write(file_contents)
except (IOError, ValueError) as e:
cleanup()
abort(500, str(e))
except Exception:
cleanup()
abort(500, "Unexpected Error")
try:
iface = dbus.Interface(self.obj, self.CERT_IFACE)
iface.Install(temp.name)
except Exception as e:
cleanup()
abort(400, str(e))
cleanup()
def do_delete(self):
delete_iface = dbus.Interface(
self.obj, dbus_interface=DELETE_IFACE)
delete_iface.Delete()
class CertificatePutHandler(RouteHandler):
''' Handles the /xyz/openbmc_project/certs/<cert_type>/<service> route. '''
verbs = ['PUT', 'DELETE']
rules = ['/xyz/openbmc_project/certs/<cert_type>/<service>']
content_type = 'application/octet-stream'
def __init__(self, app, bus):
super(CertificatePutHandler, self).__init__(
app, bus, self.verbs, self.rules, self.content_type)
def do_put(self, cert_type, service):
return CertificateHandler(self, cert_type, service).do_upload()
def do_delete(self, cert_type, service):
return CertificateHandler(self, cert_type, service).do_delete()
def find(self, **kw):
pass
def setup(self, **kw):
pass
class EventNotifier:
keyNames = {}
keyNames['event'] = 'event'
keyNames['path'] = 'path'
keyNames['intfMap'] = 'interfaces'
keyNames['propMap'] = 'properties'
keyNames['intf'] = 'interface'
def __init__(self, wsock, filters):
self.wsock = wsock
self.paths = filters.get("paths", [])
self.interfaces = filters.get("interfaces", [])
self.signals = []
self.socket_error = False
if not self.paths:
self.paths.append(None)
bus = dbus.SystemBus()
# Add a signal receiver for every path the client is interested in
for path in self.paths:
add_sig = bus.add_signal_receiver(
self.interfaces_added_handler,
dbus_interface=dbus.BUS_DAEMON_IFACE + '.ObjectManager',
signal_name='InterfacesAdded',
path=path)
chg_sig = bus.add_signal_receiver(
self.properties_changed_handler,
dbus_interface=dbus.PROPERTIES_IFACE,
signal_name='PropertiesChanged',
path=path,
path_keyword='path')
self.signals.append(add_sig)
self.signals.append(chg_sig)
loop = gobject.MainLoop()
# gobject's mainloop.run() will block the entire process, so the gevent
# scheduler and hence greenlets won't execute. The while-loop below
# works around this limitation by using gevent's sleep, instead of
# calling loop.run()
gcontext = loop.get_context()
while loop is not None:
try:
if self.socket_error:
for signal in self.signals:
signal.remove()
loop.quit()
break;
if gcontext.pending():
gcontext.iteration()
else:
# gevent.sleep puts only the current greenlet to sleep,
# not the entire process.
gevent.sleep(5)
except WebSocketError:
break
def interfaces_added_handler(self, path, iprops, **kw):
''' If the client is interested in these changes, respond to the
client. This handles d-bus interface additions.'''
if (not self.interfaces) or \
(not set(iprops).isdisjoint(self.interfaces)):
response = {}
response[self.keyNames['event']] = "InterfacesAdded"
response[self.keyNames['path']] = path
response[self.keyNames['intfMap']] = iprops
try:
self.wsock.send(json.dumps(response))
except:
self.socket_error = True
return
def properties_changed_handler(self, interface, new, old, **kw):
''' If the client is interested in these changes, respond to the
client. This handles d-bus property changes. '''
if (not self.interfaces) or (interface in self.interfaces):
path = str(kw['path'])
response = {}
response[self.keyNames['event']] = "PropertiesChanged"
response[self.keyNames['path']] = path
response[self.keyNames['intf']] = interface
response[self.keyNames['propMap']] = new
try:
self.wsock.send(json.dumps(response))
except:
self.socket_error = True
return
class EventHandler(RouteHandler):
''' Handles the /subscribe route, for clients to be able
to subscribe to BMC events. '''
verbs = ['GET']
rules = ['/subscribe']
suppress_logging = True
def __init__(self, app, bus):
super(EventHandler, self).__init__(
app, bus, self.verbs, self.rules)
def find(self, **kw):
pass
def setup(self, **kw):
pass
def do_get(self):
wsock = request.environ.get('wsgi.websocket')
if not wsock:
abort(400, 'Expected WebSocket request.')
ping_sender = Greenlet.spawn(send_ws_ping, wsock, WEBSOCKET_TIMEOUT)
filters = wsock.receive()
filters = json.loads(filters)
notifier = EventNotifier(wsock, filters)
class HostConsoleHandler(RouteHandler):
''' Handles the /console route, for clients to be able
read/write the host serial console. The way this is
done is by exposing a websocket that's mirrored to an
abstract UNIX domain socket, which is the source for
the console data. '''
verbs = ['GET']
# Naming the route console0, because the numbering will help
# on multi-bmc/multi-host systems.
rules = ['/console0']
suppress_logging = True
def __init__(self, app, bus):
super(HostConsoleHandler, self).__init__(
app, bus, self.verbs, self.rules)
def find(self, **kw):
pass
def setup(self, **kw):
pass
def read_wsock(self, wsock, sock):
while True:
try:
incoming = wsock.receive()
if incoming:
# Read websocket, write to UNIX socket
sock.send(incoming)
except Exception as e:
sock.close()
return
def read_sock(self, sock, wsock):
max_sock_read_len = 4096
while True:
try:
outgoing = sock.recv(max_sock_read_len)
if outgoing:
# Read UNIX socket, write to websocket
wsock.send(outgoing)
except Exception as e:
wsock.close()
return
def do_get(self):
wsock = request.environ.get('wsgi.websocket')
if not wsock:
abort(400, 'Expected WebSocket based request.')
# An abstract Unix socket path must be less than or equal to 108 bytes
# and does not need to be nul-terminated or padded out to 108 bytes
socket_name = "\0obmc-console"
socket_path = socket_name
sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
try:
sock.connect(socket_path)
except Exception as e:
abort(500, str(e))
wsock_reader = Greenlet.spawn(self.read_wsock, wsock, sock)
sock_reader = Greenlet.spawn(self.read_sock, sock, wsock)
ping_sender = Greenlet.spawn(send_ws_ping, wsock, WEBSOCKET_TIMEOUT)
gevent.joinall([wsock_reader, sock_reader, ping_sender])
class ImagePutHandler(RouteHandler):
''' Handles the /upload/image/<filename> route. '''
verbs = ['PUT']
rules = ['/upload/image/<filename>']
content_type = 'application/octet-stream'
def __init__(self, app, bus):
super(ImagePutHandler, self).__init__(
app, bus, self.verbs, self.rules, self.content_type)
def do_put(self, filename=''):
return ImageUploadUtils.do_upload(filename)
def find(self, **kw):
pass
def setup(self, **kw):
pass
class DownloadDumpHandler(RouteHandler):
''' Handles the /download/dump route. '''
verbs = 'GET'
rules = ['/download/dump/<dumpid>']
content_type = 'application/octet-stream'
dump_loc = '/var/lib/phosphor-debug-collector/dumps'
suppress_json_resp = True
suppress_logging = True
def __init__(self, app, bus):
super(DownloadDumpHandler, self).__init__(
app, bus, self.verbs, self.rules, self.content_type)
def do_get(self, dumpid):
return self.do_download(dumpid)
def find(self, **kw):
pass
def setup(self, **kw):
pass
def do_download(self, dumpid):
dump_loc = os.path.join(self.dump_loc, dumpid)
if not os.path.exists(dump_loc):
abort(404, "Path not found")
files = os.listdir(dump_loc)
num_files = len(files)
if num_files == 0:
abort(404, "Dump not found")
return static_file(os.path.basename(files[0]), root=dump_loc,
download=True, mimetype=self.content_type)
class WebHandler(RouteHandler):
''' Handles the routes for the web UI files. '''
verbs = 'GET'
# Match only what we know are web files, so everything else
# can get routed to the REST handlers.
rules = ['//', '/<filename:re:.+\.js>', '/<filename:re:.+\.svg>',
'/<filename:re:.+\.css>', '/<filename:re:.+\.ttf>',
'/<filename:re:.+\.eot>', '/<filename:re:.+\.woff>',
'/<filename:re:.+\.woff2>', '/<filename:re:.+\.map>',
'/<filename:re:.+\.png>', '/<filename:re:.+\.html>',
'/<filename:re:.+\.ico>']
# The mimetypes module knows about most types, but not these
content_types = {
'.eot': 'application/vnd.ms-fontobject',
'.woff': 'application/x-font-woff',
'.woff2': 'application/x-font-woff2',
'.ttf': 'application/x-font-ttf',
'.map': 'application/json'
}
_require_auth = None
suppress_json_resp = True
suppress_logging = True
def __init__(self, app, bus):
super(WebHandler, self).__init__(
app, bus, self.verbs, self.rules)
def get_type(self, filename):
''' Returns the content type and encoding for a file '''
content_type, encoding = mimetypes.guess_type(filename)
# Try our own list if mimetypes didn't recognize it
if content_type is None:
if filename[-3:] == '.gz':
filename = filename[:-3]
extension = filename[filename.rfind('.'):]
content_type = self.content_types.get(extension, None)
return content_type, encoding
def do_get(self, filename='index.html'):
# If a gzipped version exists, use that instead.
# Possible future enhancement: if the client doesn't
# accept compressed files, unzip it ourselves before sending.
if not os.path.exists(os.path.join(www_base_path, filename)):
filename = filename + '.gz'
# Though bottle should protect us, ensure path is valid
realpath = os.path.realpath(filename)
if realpath[0] == '/':
realpath = realpath[1:]
if not os.path.exists(os.path.join(www_base_path, realpath)):
abort(404, "Path not found")
mimetype, encoding = self.get_type(filename)
# Couldn't find the type - let static_file() deal with it,
# though this should never happen.
if mimetype is None:
print("Can't figure out content-type for %s" % filename)
mimetype = 'auto'
# This call will set several header fields for us,
# including the charset if the type is text.
response = static_file(filename, www_base_path, mimetype)
# static_file() will only set the encoding if the
# mimetype was auto, so set it here.
if encoding is not None:
response.set_header('Content-Encoding', encoding)
return response
def find(self, **kw):
pass
def setup(self, **kw):
pass
class AuthorizationPlugin(object):
''' Invokes an optional list of authorization callbacks. '''
name = 'authorization'
api = 2
class Compose:
def __init__(self, validators, callback, session_mgr):
self.validators = validators
self.callback = callback
self.session_mgr = session_mgr
def __call__(self, *a, **kw):
sid = request.get_cookie('sid', secret=self.session_mgr.hmac_key)
session = self.session_mgr.get_session(sid)
if request.method != 'OPTIONS':
for x in self.validators:
x(session, *a, **kw)
return self.callback(*a, **kw)
def apply(self, callback, route):
undecorated = route.get_undecorated_callback()
if not isinstance(undecorated, RouteHandler):
return callback
auth_types = getattr(
undecorated, '_require_auth', None)
if not auth_types:
return callback
return self.Compose(
auth_types, callback, undecorated.app.session_handler)
class CorsPlugin(object):
''' Add CORS headers. '''
name = 'cors'
api = 2
@staticmethod
def process_origin():
origin = request.headers.get('Origin')
if origin:
response.add_header('Access-Control-Allow-Origin', origin)
response.add_header(
'Access-Control-Allow-Credentials', 'true')
@staticmethod
def process_method_and_headers(verbs):
method = request.headers.get('Access-Control-Request-Method')
headers = request.headers.get('Access-Control-Request-Headers')
if headers:
headers = [x.lower() for x in headers.split(',')]
if method in verbs \
and headers == ['content-type']:
response.add_header('Access-Control-Allow-Methods', method)
response.add_header(
'Access-Control-Allow-Headers', 'Content-Type')
response.add_header('X-Frame-Options', 'deny')
response.add_header('X-Content-Type-Options', 'nosniff')
response.add_header('X-XSS-Protection', '1; mode=block')
response.add_header(
'Content-Security-Policy', "default-src 'self'")
response.add_header(
'Strict-Transport-Security',
'max-age=31536000; includeSubDomains; preload')
def __init__(self, app):
app.install_error_callback(self.error_callback)
def apply(self, callback, route):
undecorated = route.get_undecorated_callback()
if not isinstance(undecorated, RouteHandler):
return callback
if not getattr(undecorated, '_enable_cors', None):
return callback
def wrap(*a, **kw):
self.process_origin()
self.process_method_and_headers(undecorated._verbs)
return callback(*a, **kw)
return wrap
def error_callback(self, **kw):
self.process_origin()
class JsonApiRequestPlugin(object):
''' Ensures request content satisfies the OpenBMC json api format. '''
name = 'json_api_request'
api = 2
error_str = "Expecting request format { 'data': <value> }, got '%s'"
type_error_str = "Unsupported Content-Type: '%s'"
json_type = "application/json"
request_methods = ['PUT', 'POST', 'PATCH']
@staticmethod
def content_expected():
return request.method in JsonApiRequestPlugin.request_methods
def validate_request(self):
if request.content_length > 0 and \
request.content_type != self.json_type:
abort(415, self.type_error_str % request.content_type)
try:
request.parameter_list = request.json.get('data')
except ValueError as e:
abort(400, str(e))
except (AttributeError, KeyError, TypeError):
abort(400, self.error_str % request.json)
def apply(self, callback, route):
content_type = getattr(
route.get_undecorated_callback(), '_content_type', None)
if self.json_type != content_type:
return callback
verbs = getattr(
route.get_undecorated_callback(), '_verbs', None)
if verbs is None:
return callback
if not set(self.request_methods).intersection(verbs):
return callback
def wrap(*a, **kw):
if self.content_expected():
self.validate_request()
return callback(*a, **kw)
return wrap
class JsonApiRequestTypePlugin(object):
''' Ensures request content type satisfies the OpenBMC json api format. '''
name = 'json_api_method_request'
api = 2
error_str = "Expecting request format { 'data': %s }, got '%s'"
json_type = "application/json"
def apply(self, callback, route):
content_type = getattr(
route.get_undecorated_callback(), '_content_type', None)
if self.json_type != content_type:
return callback
request_type = getattr(
route.get_undecorated_callback(), 'request_type', None)
if request_type is None:
return callback
def validate_request():
if not isinstance(request.parameter_list, request_type):
abort(400, self.error_str % (str(request_type), request.json))
def wrap(*a, **kw):
if JsonApiRequestPlugin.content_expected():
validate_request()
return callback(*a, **kw)
return wrap
class JsonErrorsPlugin(JSONPlugin):
''' Extend the Bottle JSONPlugin such that it also encodes error
responses. '''
def __init__(self, app, **kw):
super(JsonErrorsPlugin, self).__init__(**kw)
self.json_opts = {
x: y for x, y in kw.items()
if x in ['indent', 'sort_keys']}
app.install_error_callback(self.error_callback)
def error_callback(self, response_object, response_body, **kw):
response_body['body'] = json.dumps(response_object, **self.json_opts)
response.content_type = 'application/json'
class JsonApiResponsePlugin(object):
''' Emits responses in the OpenBMC json api format. '''
name = 'json_api_response'
api = 2
@staticmethod
def has_body():
return request.method not in ['OPTIONS']
def __init__(self, app):
app.install_error_callback(self.error_callback)
@staticmethod
def dbus_boolean_to_bool(data):
''' Convert all dbus.Booleans to true/false instead of 1/0 as
the JSON encoder thinks they're ints. Note that unlike
dicts and lists, tuples (from a dbus.Struct) are immutable
so they need special handling. '''
def walkdict(data):
for key, value in data.items():
if isinstance(value, dbus.Boolean):
data[key] = bool(value)
elif isinstance(value, tuple):
data[key] = walktuple(value)
else:
JsonApiResponsePlugin.dbus_boolean_to_bool(value)
def walklist(data):
for i in range(len(data)):
if isinstance(data[i], dbus.Boolean):
data[i] = bool(data[i])
elif isinstance(data[i], tuple):
data[i] = walktuple(data[i])
else:
JsonApiResponsePlugin.dbus_boolean_to_bool(data[i])
def walktuple(data):
new = []
for item in data:
if isinstance(item, dbus.Boolean):
item = bool(item)
else:
JsonApiResponsePlugin.dbus_boolean_to_bool(item)
new.append(item)
return tuple(new)
if isinstance(data, dict):
walkdict(data)
elif isinstance(data, list):
walklist(data)
def apply(self, callback, route):
skip = getattr(
route.get_undecorated_callback(), 'suppress_json_resp', None)
if skip:
return callback
def wrap(*a, **kw):
data = callback(*a, **kw)
JsonApiResponsePlugin.dbus_boolean_to_bool(data)
if self.has_body():
resp = {'data': data}
resp['status'] = 'ok'
resp['message'] = response.status_line
return resp
return wrap
def error_callback(self, error, response_object, **kw):
response_object['message'] = error.status_line
response_object['status'] = 'error'
response_object.setdefault('data', {})['description'] = str(error.body)
if error.status_code == 500:
response_object['data']['exception'] = repr(error.exception)
response_object['data']['traceback'] = error.traceback.splitlines()
class JsonpPlugin(object):
''' Json javascript wrapper. '''
name = 'jsonp'
api = 2
def __init__(self, app, **kw):
app.install_error_callback(self.error_callback)
@staticmethod
def to_jsonp(json):
jwrapper = request.query.callback or None
if(jwrapper):
response.set_header('Content-Type', 'application/javascript')
json = jwrapper + '(' + json + ');'
return json
def apply(self, callback, route):
def wrap(*a, **kw):
return self.to_jsonp(callback(*a, **kw))
return wrap
def error_callback(self, response_body, **kw):
response_body['body'] = self.to_jsonp(response_body['body'])
class ContentCheckerPlugin(object):
''' Ensures that a route is associated with the expected content-type
header. '''
name = 'content_checker'
api = 2
class Checker:
def __init__(self, type, callback):
self.expected_type = type
self.callback = callback
self.error_str = "Expecting content type '%s', got '%s'"
def __call__(self, *a, **kw):
if request.method in ['PUT', 'POST', 'PATCH'] and \
self.expected_type and \
self.expected_type != request.content_type:
abort(415, self.error_str % (self.expected_type,
request.content_type))
return self.callback(*a, **kw)
def apply(self, callback, route):
content_type = getattr(
route.get_undecorated_callback(), '_content_type', None)
return self.Checker(content_type, callback)
class LoggingPlugin(object):
''' Wraps a request in order to emit a log after the request is handled. '''
name = 'loggingp'
api = 2
class Logger:
def __init__(self, suppress_json_logging, callback, app):
self.suppress_json_logging = suppress_json_logging
self.callback = callback
self.app = app
self.logging_enabled = None
self.bus = dbus.SystemBus()
self.dbus_path = '/xyz/openbmc_project/logging/rest_api_logs'
self.no_json = [
'/xyz/openbmc_project/user/ldap/action/CreateConfig'
]
self.bus.add_signal_receiver(
self.properties_changed_handler,
dbus_interface=dbus.PROPERTIES_IFACE,
signal_name='PropertiesChanged',
path=self.dbus_path)
Greenlet.spawn(self.dbus_loop)
def __call__(self, *a, **kw):
resp = self.callback(*a, **kw)
if not self.enabled():
return resp
if request.method == 'GET':
return resp
json = request.json
if self.suppress_json_logging:
json = None
elif any(substring in request.url for substring in self.no_json):
json = None
session = self.app.session_handler.get_session_from_cookie()
user = None
if "/login" in request.url:
user = request.parameter_list[0]
elif session is not None:
user = session['user']
print("{remote} user:{user} {method} {url} json:{json} {status}" \
.format(
user=user,
remote=request.remote_addr,
method=request.method,
url=request.url,
json=json,
status=response.status))
return resp
def enabled(self):
if self.logging_enabled is None:
try:
obj = self.bus.get_object(
'xyz.openbmc_project.Settings',
self.dbus_path)
iface = dbus.Interface(obj, dbus.PROPERTIES_IFACE)
logging_enabled = iface.Get(
'xyz.openbmc_project.Object.Enable',
'Enabled')
self.logging_enabled = logging_enabled
except dbus.exceptions.DBusException:
self.logging_enabled = False
return self.logging_enabled
def dbus_loop(self):
loop = gobject.MainLoop()
gcontext = loop.get_context()
while loop is not None:
try:
if gcontext.pending():
gcontext.iteration()
else:
gevent.sleep(5)
except Exception as e:
break
def properties_changed_handler(self, interface, new, old, **kw):
self.logging_enabled = new.values()[0]
def apply(self, callback, route):
cb = route.get_undecorated_callback()
skip = getattr(
cb, 'suppress_logging', None)
if skip:
return callback
suppress_json_logging = getattr(
cb, 'suppress_json_logging', None)
return self.Logger(suppress_json_logging, callback, cb.app)
class App(Bottle):
def __init__(self, **kw):
super(App, self).__init__(autojson=False)
self.have_wsock = kw.get('have_wsock', False)
self.with_bmc_check = '--with-bmc-check' in sys.argv
self.bus = dbus.SystemBus()
self.mapper = obmc.mapper.Mapper(self.bus)
self.error_callbacks = []
self.install_hooks()
self.install_plugins()
self.create_handlers()
self.install_handlers()
def install_plugins(self):
# install json api plugins
json_kw = {'indent': 2, 'sort_keys': True}
self.install(AuthorizationPlugin())
self.install(CorsPlugin(self))
self.install(ContentCheckerPlugin())
self.install(JsonpPlugin(self, **json_kw))
self.install(JsonErrorsPlugin(self, **json_kw))
self.install(JsonApiResponsePlugin(self))
self.install(JsonApiRequestPlugin())
self.install(JsonApiRequestTypePlugin())
self.install(LoggingPlugin())
def install_hooks(self):
self.error_handler_type = type(self.default_error_handler)
self.original_error_handler = self.default_error_handler
self.default_error_handler = self.error_handler_type(
self.custom_error_handler, self, Bottle)
self.real_router_match = self.router.match
self.router.match = self.custom_router_match
self.add_hook('before_request', self.strip_extra_slashes)
def create_handlers(self):
# create route handlers
self.session_handler = SessionHandler(self, self.bus)
self.web_handler = WebHandler(self, self.bus)
self.directory_handler = DirectoryHandler(self, self.bus)
self.list_names_handler = ListNamesHandler(self, self.bus)
self.list_handler = ListHandler(self, self.bus)
self.method_handler = MethodHandler(self, self.bus)
self.property_handler = PropertyHandler(self, self.bus)
self.schema_handler = SchemaHandler(self, self.bus)
self.image_upload_post_handler = ImagePostHandler(self, self.bus)
self.image_upload_put_handler = ImagePutHandler(self, self.bus)
self.download_dump_get_handler = DownloadDumpHandler(self, self.bus)
self.certificate_put_handler = CertificatePutHandler(self, self.bus)
if self.have_wsock:
self.event_handler = EventHandler(self, self.bus)
self.host_console_handler = HostConsoleHandler(self, self.bus)
self.instance_handler = InstanceHandler(self, self.bus)
def install_handlers(self):
self.session_handler.install()
self.web_handler.install()
self.directory_handler.install()
self.list_names_handler.install()
self.list_handler.install()
self.method_handler.install()
self.property_handler.install()
self.schema_handler.install()
self.image_upload_post_handler.install()
self.image_upload_put_handler.install()
self.download_dump_get_handler.install()
self.certificate_put_handler.install()
if self.have_wsock:
self.event_handler.install()
self.host_console_handler.install()
# this has to come last, since it matches everything
self.instance_handler.install()
def install_error_callback(self, callback):
self.error_callbacks.insert(0, callback)
def custom_router_match(self, environ):
''' The built-in Bottle algorithm for figuring out if a 404 or 405 is
needed doesn't work for us since the instance rules match
everything. This monkey-patch lets the route handler figure
out which response is needed. This could be accomplished
with a hook but that would require calling the router match
function twice.
'''
route, args = self.real_router_match(environ)
if isinstance(route.callback, RouteHandler):
route.callback._setup(**args)
return route, args
def custom_error_handler(self, res, error):
''' Allow plugins to modify error responses too via this custom
error handler. '''
response_object = {}
response_body = {}
for x in self.error_callbacks:
x(error=error,
response_object=response_object,
response_body=response_body)
return response_body.get('body', "")
@staticmethod
def strip_extra_slashes():
path = request.environ['PATH_INFO']
trailing = ("", "/")[path[-1] == '/']
parts = list(filter(bool, path.split('/')))
request.environ['PATH_INFO'] = '/' + '/'.join(parts) + trailing