radicale/radicale/__init__.py
2013-01-31 17:27:23 +01:00

565 lines
21 KiB
Python

# -*- coding: utf-8 -*-
#
# This file is part of Radicale Server - Calendar Server
# Copyright © 2008-2012 Guillaume Ayoub
# Copyright © 2008 Nicolas Kandel
# Copyright © 2008 Pascal Halter
#
# This library is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Radicale. If not, see <http://www.gnu.org/licenses/>.
"""
Radicale Server module.
This module offers a WSGI application class.
To use this module, you should take a look at the file ``radicale.py`` that
should have been included in this package.
"""
import os
import pprint
import base64
import posixpath
import socket
import ssl
import wsgiref.simple_server
# Manage Python2/3 different modules
# pylint: disable=F0401,E0611
try:
from http import client
from urllib.parse import quote, unquote, urlparse
except ImportError:
import httplib as client
from urllib import quote, unquote
from urlparse import urlparse
# pylint: enable=F0401,E0611
from . import auth, config, ical, log, rights, storage, xmlutils
VERSION = "git"
# Standard "not allowed" response that is returned when an authenticated user
# tries to access information they don't have rights to
NOT_ALLOWED = (client.FORBIDDEN, {}, None)
# Standard "authenticate" response that is returned when a user tries to access
# non-public information w/o submitting proper authentication credentials
WRONG_CREDENTIALS = (
client.UNAUTHORIZED,
{"WWW-Authenticate": "Basic realm=\"Radicale - Password Required\""},
None)
class HTTPServer(wsgiref.simple_server.WSGIServer, object):
"""HTTP server."""
def __init__(self, address, handler, bind_and_activate=True):
"""Create server."""
ipv6 = ":" in address[0]
if ipv6:
self.address_family = socket.AF_INET6
# Do not bind and activate, as we might change socket options
super(HTTPServer, self).__init__(address, handler, False)
if ipv6:
# Only allow IPv6 connections to the IPv6 socket
self.socket.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
if bind_and_activate:
self.server_bind()
self.server_activate()
class HTTPSServer(HTTPServer):
"""HTTPS server."""
def __init__(self, address, handler):
"""Create server by wrapping HTTP socket in an SSL socket."""
super(HTTPSServer, self).__init__(address, handler, False)
# Test if the SSL files can be read
for name in ("certificate", "key"):
filename = config.get("server", name)
try:
open(filename, "r").close()
except IOError as exception:
log.LOGGER.warn(
"Error while reading SSL %s %r: %s" % (
name, filename, exception))
self.socket = ssl.wrap_socket(
self.socket,
server_side=True,
certfile=config.get("server", "certificate"),
keyfile=config.get("server", "key"),
ssl_version=ssl.PROTOCOL_SSLv23)
self.server_bind()
self.server_activate()
class RequestHandler(wsgiref.simple_server.WSGIRequestHandler):
"""HTTP requests handler."""
def log_message(self, *args, **kwargs):
"""Disable inner logging management."""
def address_string(self):
"""Client address, formatted for logging."""
if config.getboolean("server", "dns_lookup"):
return \
wsgiref.simple_server.WSGIRequestHandler.address_string(self)
else:
return self.client_address[0]
class Application(object):
"""WSGI application managing collections."""
def __init__(self):
"""Initialize application."""
super(Application, self).__init__()
auth.load()
rights.load()
storage.load()
self.encoding = config.get("encoding", "request")
if config.getboolean("logging", "full_environment"):
self.headers_log = lambda environ: environ
# This method is overriden in __init__ if full_environment is set
# pylint: disable=E0202
@staticmethod
def headers_log(environ):
"""Remove environment variables from the headers for logging."""
request_environ = dict(environ)
for shell_variable in os.environ:
if shell_variable in request_environ:
del request_environ[shell_variable]
return request_environ
# pylint: enable=E0202
def decode(self, text, environ):
"""Try to magically decode ``text`` according to given ``environ``."""
# List of charsets to try
charsets = []
# First append content charset given in the request
content_type = environ.get("CONTENT_TYPE")
if content_type and "charset=" in content_type:
charsets.append(content_type.split("charset=")[1].strip())
# Then append default Radicale charset
charsets.append(self.encoding)
# Then append various fallbacks
charsets.append("utf-8")
charsets.append("iso8859-1")
# Try to decode
for charset in charsets:
try:
return text.decode(charset)
except UnicodeDecodeError:
pass
raise UnicodeDecodeError
@staticmethod
def sanitize_uri(uri):
"""Unquote and remove /../ to prevent access to other data."""
uri = unquote(uri)
trailing_slash = "/" if uri.endswith("/") else ""
uri = posixpath.normpath(uri)
trailing_slash = "" if uri == "/" else trailing_slash
return uri + trailing_slash
def collect_allowed_items(self, items, user):
"""Get items from request that user is allowed to access."""
read_last_collection_allowed = None
write_last_collection_allowed = None
read_allowed_items = []
write_allowed_items = []
for item in items:
if isinstance(item, ical.Collection):
if rights.read_authorized(user, item):
log.LOGGER.debug(
"%s has read access to collection %s" %
(user or "Anonymous", item.url or "/"))
read_last_collection_allowed = True
read_allowed_items.append(item)
else:
log.LOGGER.debug(
"%s has NO read access to collection %s" %
(user or "Anonymous", item.url or "/"))
read_last_collection_allowed = False
if rights.write_authorized(user, item):
log.LOGGER.debug(
"%s has write access to collection %s" %
(user or "Anonymous", item.url or "/"))
write_last_collection_allowed = True
write_allowed_items.append(item)
else:
log.LOGGER.debug(
"%s has NO write access to collection %s" %
(user or "Anonymous", item.url or "/"))
write_last_collection_allowed = False
else:
# item is not a collection, it's the child of the last
# collection we've met in the loop. Only add this item
# if this last collection was allowed.
if read_last_collection_allowed:
log.LOGGER.debug(
"%s has read access to item %s" %
(user or "Anonymous", item.name))
read_allowed_items.append(item)
else:
log.LOGGER.debug(
"%s has NO read access to item %s" %
(user or "Anonymous", item.name))
if write_last_collection_allowed:
log.LOGGER.debug(
"%s has write access to item %s" %
(user or "Anonymous", item.name))
write_allowed_items.append(item)
else:
log.LOGGER.debug(
"%s has NO write access to item %s" %
(user or "Anonymous", item.name))
return read_allowed_items, write_allowed_items
def __call__(self, environ, start_response):
"""Manage a request."""
log.LOGGER.info("%s request at %s received" % (
environ["REQUEST_METHOD"], environ["PATH_INFO"]))
headers = pprint.pformat(self.headers_log(environ))
log.LOGGER.debug("Request headers:\n%s" % headers)
# Sanitize request URI
environ["PATH_INFO"] = self.sanitize_uri(environ["PATH_INFO"])
log.LOGGER.debug("Sanitized path: %s", environ["PATH_INFO"])
# Get content
content_length = int(environ.get("CONTENT_LENGTH") or 0)
if content_length:
content = self.decode(
environ["wsgi.input"].read(content_length), environ)
log.LOGGER.debug("Request content:\n%s" % content)
else:
content = None
path = environ["PATH_INFO"]
# Find collection(s)
items = ical.Collection.from_path(
path, environ.get("HTTP_DEPTH", "0"))
# Get function corresponding to method
function = getattr(self, environ["REQUEST_METHOD"].lower())
# Ask authentication backend to check rights
authorization = environ.get("HTTP_AUTHORIZATION", None)
if authorization:
authorization = \
authorization.lstrip("Basic").strip().encode("ascii")
user, password = self.decode(
base64.b64decode(authorization), environ).split(":", 1)
else:
user = password = None
if not items or function == self.options or \
auth.is_authenticated(user, password):
read_allowed_items, write_allowed_items = \
self.collect_allowed_items(items, user)
if read_allowed_items or write_allowed_items or \
function == self.options:
# Collections found
status, headers, answer = function(
environ, read_allowed_items, write_allowed_items, content,
user)
else:
# Good user but has no rights to any of the given collections
status, headers, answer = NOT_ALLOWED
else:
# Unknown or unauthorized user
log.LOGGER.info(
"%s refused" % (user or "Anonymous user"))
status, headers, answer = WRONG_CREDENTIALS
# Set content length
if answer:
log.LOGGER.debug(
"Response content:\n%s" % self.decode(answer, environ))
headers["Content-Length"] = str(len(answer))
# Start response
status = "%i %s" % (status, client.responses.get(status, "Unknown"))
log.LOGGER.debug("Answer status: %s" % status)
start_response(status, list(headers.items()))
# Return response content
return [answer] if answer else []
# All these functions must have the same parameters, some are useless
# pylint: disable=W0612,W0613,R0201
def delete(self, environ, read_collections, write_collections, content,
user):
"""Manage DELETE request."""
if not len(write_collections):
return client.PRECONDITION_FAILED, {}, None
collection = write_collections[0]
if collection.path == environ["PATH_INFO"].strip("/"):
# Path matching the collection, the collection must be deleted
item = collection
else:
# Try to get an item matching the path
item = collection.get_item(
xmlutils.name_from_path(environ["PATH_INFO"], collection))
if item:
# Evolution bug workaround
etag = environ.get("HTTP_IF_MATCH", item.etag).replace("\\", "")
if etag == item.etag:
# No ETag precondition or precondition verified, delete item
answer = xmlutils.delete(environ["PATH_INFO"], collection)
return client.OK, {}, answer
# No item or ETag precondition not verified, do not delete item
return client.PRECONDITION_FAILED, {}, None
def get(self, environ, read_collections, write_collections, content, user):
"""Manage GET request.
In Radicale, GET requests create collections when the URL is not
available. This is useful for clients with no MKCOL or MKCALENDAR
support.
"""
# Display a "Radicale works!" message if the root URL is requested
if environ["PATH_INFO"] == "/":
headers = {"Content-type": "text/html"}
answer = b"<!DOCTYPE html>\n<title>Radicale</title>Radicale works!"
return client.OK, headers, answer
if not len(read_collections):
return NOT_ALLOWED
collection = read_collections[0]
item_name = xmlutils.name_from_path(environ["PATH_INFO"], collection)
if item_name:
# Get collection item
item = collection.get_item(item_name)
if item:
items = collection.timezones
items.append(item)
answer_text = ical.serialize(
collection.tag, collection.headers, items)
etag = item.etag
else:
return client.GONE, {}, None
else:
# Create the collection if it does not exist
if not collection.exists:
if collection in write_collections:
log.LOGGER.debug(
"Creating collection %s" % collection.name)
collection.write()
else:
log.LOGGER.debug(
"Collection %s not available and could not be created "
"due to missing write rights" % collection.name)
return NOT_ALLOWED
# Get whole collection
answer_text = collection.text
etag = collection.etag
headers = {
"Content-Type": collection.mimetype,
"Last-Modified": collection.last_modified,
"ETag": etag}
answer = answer_text.encode(self.encoding)
return client.OK, headers, answer
def head(self, environ, read_collections, write_collections, content,
user):
"""Manage HEAD request."""
status, headers, answer = self.get(
environ, read_collections, write_collections, content, user)
return status, headers, None
def mkcalendar(self, environ, read_collections, write_collections, content,
user):
"""Manage MKCALENDAR request."""
if not len(write_collections):
return NOT_ALLOWED
collection = write_collections[0]
props = xmlutils.props_from_request(content)
timezone = props.get("C:calendar-timezone")
if timezone:
collection.replace("", timezone)
del props["C:calendar-timezone"]
with collection.props as collection_props:
for key, value in props.items():
collection_props[key] = value
collection.write()
return client.CREATED, {}, None
def mkcol(self, environ, read_collections, write_collections, content,
user):
"""Manage MKCOL request."""
if not len(write_collections):
return NOT_ALLOWED
collection = write_collections[0]
props = xmlutils.props_from_request(content)
with collection.props as collection_props:
for key, value in props.items():
collection_props[key] = value
collection.write()
return client.CREATED, {}, None
def move(self, environ, read_collections, write_collections, content,
user):
"""Manage MOVE request."""
if not len(write_collections):
return NOT_ALLOWED
from_collection = write_collections[0]
from_name = xmlutils.name_from_path(
environ["PATH_INFO"], from_collection)
if from_name:
item = from_collection.get_item(from_name)
if item:
# Move the item
to_url_parts = urlparse(environ["HTTP_DESTINATION"])
if to_url_parts.netloc == environ["HTTP_HOST"]:
to_url = to_url_parts.path
to_path, to_name = to_url.rstrip("/").rsplit("/", 1)
to_collection = ical.Collection.from_path(
to_path, depth="0")[0]
if to_collection in write_collections:
to_collection.append(to_name, item.text)
from_collection.remove(from_name)
return client.CREATED, {}, None
else:
return NOT_ALLOWED
else:
# Remote destination server, not supported
return client.BAD_GATEWAY, {}, None
else:
# No item found
return client.GONE, {}, None
else:
# Moving collections, not supported
return client.FORBIDDEN, {}, None
def options(self, environ, read_collections, write_collections, content,
user):
"""Manage OPTIONS request."""
headers = {
"Allow": ("DELETE, HEAD, GET, MKCALENDAR, MKCOL, MOVE, "
"OPTIONS, PROPFIND, PROPPATCH, PUT, REPORT"),
"DAV": "1, 2, 3, calendar-access, addressbook, extended-mkcol"}
return client.OK, headers, None
def propfind(self, environ, read_collections, write_collections, content,
user):
"""Manage PROPFIND request."""
# Rights is handled by collection in xmlutils.propfind
headers = {
"DAV": "1, 2, 3, calendar-access, addressbook, extended-mkcol",
"Content-Type": "text/xml"}
collections = set(read_collections + write_collections)
answer = xmlutils.propfind(
environ["PATH_INFO"], content, collections, user)
return client.MULTI_STATUS, headers, answer
def proppatch(self, environ, read_collections, write_collections, content,
user):
"""Manage PROPPATCH request."""
if not len(write_collections):
return NOT_ALLOWED
collection = write_collections[0]
answer = xmlutils.proppatch(
environ["PATH_INFO"], content, collection)
headers = {
"DAV": "1, 2, 3, calendar-access, addressbook, extended-mkcol",
"Content-Type": "text/xml"}
return client.MULTI_STATUS, headers, answer
def put(self, environ, read_collections, write_collections, content, user):
"""Manage PUT request."""
if not len(write_collections):
return NOT_ALLOWED
collection = write_collections[0]
collection.set_mimetype(environ.get("CONTENT_TYPE"))
headers = {}
item_name = xmlutils.name_from_path(environ["PATH_INFO"], collection)
item = collection.get_item(item_name)
# Evolution bug workaround
etag = environ.get("HTTP_IF_MATCH", "").replace("\\", "")
match = environ.get("HTTP_IF_NONE_MATCH", "") == "*"
if (not item and not etag) or (
item and ((etag or item.etag) == item.etag) and not match):
# PUT allowed in 3 cases
# Case 1: No item and no ETag precondition: Add new item
# Case 2: Item and ETag precondition verified: Modify item
# Case 3: Item and no Etag precondition: Force modifying item
xmlutils.put(environ["PATH_INFO"], content, collection)
status = client.CREATED
# Try to return the etag in the header.
# If the added item does't have the same name as the one given
# by the client, then there's no obvious way to generate an
# etag, we can safely ignore it.
new_item = collection.get_item(item_name)
if new_item:
headers["ETag"] = new_item.etag
else:
# PUT rejected in all other cases
status = client.PRECONDITION_FAILED
return status, headers, None
def report(self, environ, read_collections, write_collections, content,
user):
"""Manage REPORT request."""
if not len(read_collections):
return NOT_ALLOWED
collection = read_collections[0]
headers = {"Content-Type": "text/xml"}
answer = xmlutils.report(environ["PATH_INFO"], content, collection)
return client.MULTI_STATUS, headers, answer
# pylint: enable=W0612,W0613,R0201