forked-synapse/synapse/handlers/identity.py
2019-09-24 14:39:50 +01:00

592 lines
22 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2015, 2016 OpenMarket Ltd
# Copyright 2017 Vector Creations Ltd
# Copyright 2018 New Vector Ltd
#
# 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.
"""Utilities for interacting with Identity Servers"""
import logging
import urllib
from canonicaljson import json
from twisted.internet import defer
from twisted.internet.error import TimeoutError
from synapse.api.errors import (
CodeMessageException,
Codes,
HttpResponseException,
SynapseError,
)
from synapse.config.emailconfig import ThreepidBehaviour
from synapse.http.client import SimpleHttpClient
from synapse.util.stringutils import random_string
from ._base import BaseHandler
logger = logging.getLogger(__name__)
class IdentityHandler(BaseHandler):
def __init__(self, hs):
super(IdentityHandler, self).__init__(hs)
self.http_client = SimpleHttpClient(hs)
# We create a blacklisting instance of SimpleHttpClient for contacting identity
# servers specified by clients
self.blacklisting_http_client = SimpleHttpClient(
hs, ip_blacklist=hs.config.federation_ip_range_blacklist
)
self.federation_http_client = hs.get_http_client()
self.hs = hs
@defer.inlineCallbacks
def threepid_from_creds(self, id_server, creds):
"""
Retrieve and validate a threepid identifier from a "credentials" dictionary against a
given identity server
Args:
id_server (str): The identity server to validate 3PIDs against. Must be a
complete URL including the protocol (http(s)://)
creds (dict[str, str]): Dictionary containing the following keys:
* client_secret|clientSecret: A unique secret str provided by the client
* sid: The ID of the validation session
Returns:
Deferred[dict[str,str|int]|None]: A dictionary consisting of response params to
the /getValidated3pid endpoint of the Identity Service API, or None if the
threepid was not found
"""
client_secret = creds.get("client_secret") or creds.get("clientSecret")
if not client_secret:
raise SynapseError(
400, "Missing param client_secret in creds", errcode=Codes.MISSING_PARAM
)
session_id = creds.get("sid")
if not session_id:
raise SynapseError(
400, "Missing param session_id in creds", errcode=Codes.MISSING_PARAM
)
query_params = {"sid": session_id, "client_secret": client_secret}
url = id_server + "/_matrix/identity/api/v1/3pid/getValidated3pid"
try:
data = yield self.http_client.get_json(url, query_params)
except TimeoutError:
raise SynapseError(500, "Timed out contacting identity server")
except HttpResponseException as e:
logger.info(
"%s returned %i for threepid validation for: %s",
id_server,
e.code,
creds,
)
return None
# Old versions of Sydent return a 200 http code even on a failed validation
# check. Thus, in addition to the HttpResponseException check above (which
# checks for non-200 errors), we need to make sure validation_session isn't
# actually an error, identified by the absence of a "medium" key
# See https://github.com/matrix-org/sydent/issues/215 for details
if "medium" in data:
return data
logger.info("%s reported non-validated threepid: %s", id_server, creds)
return None
@defer.inlineCallbacks
def bind_threepid(
self, client_secret, sid, mxid, id_server, id_access_token=None, use_v2=True
):
"""Bind a 3PID to an identity server
Args:
client_secret (str): A unique secret provided by the client
sid (str): The ID of the validation session
mxid (str): The MXID to bind the 3PID to
id_server (str): The domain of the identity server to query
id_access_token (str): The access token to authenticate to the identity
server with, if necessary. Required if use_v2 is true
use_v2 (bool): Whether to use v2 Identity Service API endpoints. Defaults to True
Returns:
Deferred[dict]: The response from the identity server
"""
logger.debug("Proxying threepid bind request for %s to %s", mxid, id_server)
# If an id_access_token is not supplied, force usage of v1
if id_access_token is None:
use_v2 = False
# Decide which API endpoint URLs to use
headers = {}
bind_data = {"sid": sid, "client_secret": client_secret, "mxid": mxid}
if use_v2:
bind_url = "https://%s/_matrix/identity/v2/3pid/bind" % (id_server,)
headers["Authorization"] = create_id_access_token_header(id_access_token)
else:
bind_url = "https://%s/_matrix/identity/api/v1/3pid/bind" % (id_server,)
try:
# Use the blacklisting http client as this call is only to identity servers
# provided by a client
data = yield self.blacklisting_http_client.post_json_get_json(
bind_url, bind_data, headers=headers
)
# Remember where we bound the threepid
yield self.store.add_user_bound_threepid(
user_id=mxid,
medium=data["medium"],
address=data["address"],
id_server=id_server,
)
return data
except HttpResponseException as e:
if e.code != 404 or not use_v2:
logger.error("3PID bind failed with Matrix error: %r", e)
raise e.to_synapse_error()
except TimeoutError:
raise SynapseError(500, "Timed out contacting identity server")
except CodeMessageException as e:
data = json.loads(e.msg) # XXX WAT?
return data
logger.info("Got 404 when POSTing JSON %s, falling back to v1 URL", bind_url)
res = yield self.bind_threepid(
client_secret, sid, mxid, id_server, id_access_token, use_v2=False
)
return res
@defer.inlineCallbacks
def try_unbind_threepid(self, mxid, threepid):
"""Attempt to remove a 3PID from an identity server, or if one is not provided, all
identity servers we're aware the binding is present on
Args:
mxid (str): Matrix user ID of binding to be removed
threepid (dict): Dict with medium & address of binding to be
removed, and an optional id_server.
Raises:
SynapseError: If we failed to contact the identity server
Returns:
Deferred[bool]: True on success, otherwise False if the identity
server doesn't support unbinding (or no identity server found to
contact).
"""
if threepid.get("id_server"):
id_servers = [threepid["id_server"]]
else:
id_servers = yield self.store.get_id_servers_user_bound(
user_id=mxid, medium=threepid["medium"], address=threepid["address"]
)
# We don't know where to unbind, so we don't have a choice but to return
if not id_servers:
return False
changed = True
for id_server in id_servers:
changed &= yield self.try_unbind_threepid_with_id_server(
mxid, threepid, id_server
)
return changed
@defer.inlineCallbacks
def try_unbind_threepid_with_id_server(self, mxid, threepid, id_server):
"""Removes a binding from an identity server
Args:
mxid (str): Matrix user ID of binding to be removed
threepid (dict): Dict with medium & address of binding to be removed
id_server (str): Identity server to unbind from
Raises:
SynapseError: If we failed to contact the identity server
Returns:
Deferred[bool]: True on success, otherwise False if the identity
server doesn't support unbinding
"""
url = "https://%s/_matrix/identity/api/v1/3pid/unbind" % (id_server,)
url_bytes = "/_matrix/identity/api/v1/3pid/unbind".encode("ascii")
content = {
"mxid": mxid,
"threepid": {"medium": threepid["medium"], "address": threepid["address"]},
}
# we abuse the federation http client to sign the request, but we have to send it
# using the normal http client since we don't want the SRV lookup and want normal
# 'browser-like' HTTPS.
auth_headers = self.federation_http_client.build_auth_headers(
destination=None,
method="POST",
url_bytes=url_bytes,
content=content,
destination_is=id_server,
)
headers = {b"Authorization": auth_headers}
try:
# Use the blacklisting http client as this call is only to identity servers
# provided by a client
yield self.blacklisting_http_client.post_json_get_json(
url, content, headers
)
changed = True
except HttpResponseException as e:
changed = False
if e.code in (400, 404, 501):
# The remote server probably doesn't support unbinding (yet)
logger.warn("Received %d response while unbinding threepid", e.code)
else:
logger.error("Failed to unbind threepid on identity server: %s", e)
raise SynapseError(500, "Failed to contact identity server")
except TimeoutError:
raise SynapseError(500, "Timed out contacting identity server")
yield self.store.remove_user_bound_threepid(
user_id=mxid,
medium=threepid["medium"],
address=threepid["address"],
id_server=id_server,
)
return changed
@defer.inlineCallbacks
def send_threepid_validation(
self,
email_address,
client_secret,
send_attempt,
send_email_func,
next_link=None,
):
"""Send a threepid validation email for password reset or
registration purposes
Args:
email_address (str): The user's email address
client_secret (str): The provided client secret
send_attempt (int): Which send attempt this is
send_email_func (func): A function that takes an email address, token,
client_secret and session_id, sends an email
and returns a Deferred.
next_link (str|None): The URL to redirect the user to after validation
Returns:
The new session_id upon success
Raises:
SynapseError is an error occurred when sending the email
"""
# Check that this email/client_secret/send_attempt combo is new or
# greater than what we've seen previously
session = yield self.store.get_threepid_validation_session(
"email", client_secret, address=email_address, validated=False
)
# Check to see if a session already exists and that it is not yet
# marked as validated
if session and session.get("validated_at") is None:
session_id = session["session_id"]
last_send_attempt = session["last_send_attempt"]
# Check that the send_attempt is higher than previous attempts
if send_attempt <= last_send_attempt:
# If not, just return a success without sending an email
return session_id
else:
# An non-validated session does not exist yet.
# Generate a session id
session_id = random_string(16)
if next_link:
# Manipulate the next_link to add the sid, because the caller won't get
# it until we send a response, by which time we've sent the mail.
if "?" in next_link:
next_link += "&"
else:
next_link += "?"
next_link += "sid=" + urllib.parse.quote(session_id)
# Generate a new validation token
token = random_string(32)
# Send the mail with the link containing the token, client_secret
# and session_id
try:
yield send_email_func(email_address, token, client_secret, session_id)
except Exception:
logger.exception(
"Error sending threepid validation email to %s", email_address
)
raise SynapseError(500, "An error was encountered when sending the email")
token_expires = (
self.hs.clock.time_msec() + self.hs.config.email_validation_token_lifetime
)
yield self.store.start_or_continue_validation_session(
"email",
email_address,
session_id,
client_secret,
send_attempt,
next_link,
token,
token_expires,
)
return session_id
@defer.inlineCallbacks
def requestEmailToken(
self, id_server, email, client_secret, send_attempt, next_link=None
):
"""
Request an external server send an email on our behalf for the purposes of threepid
validation.
Args:
id_server (str): The identity server to proxy to
email (str): The email to send the message to
client_secret (str): The unique client_secret sends by the user
send_attempt (int): Which attempt this is
next_link: A link to redirect the user to once they submit the token
Returns:
The json response body from the server
"""
params = {
"email": email,
"client_secret": client_secret,
"send_attempt": send_attempt,
}
if next_link:
params["next_link"] = next_link
if self.hs.config.using_identity_server_from_trusted_list:
# Warn that a deprecated config option is in use
logger.warn(
'The config option "trust_identity_server_for_password_resets" '
'has been replaced by "account_threepid_delegate". '
"Please consult the sample config at docs/sample_config.yaml for "
"details and update your config file."
)
try:
data = yield self.http_client.post_json_get_json(
id_server + "/_matrix/identity/api/v1/validate/email/requestToken",
params,
)
return data
except HttpResponseException as e:
logger.info("Proxied requestToken failed: %r", e)
raise e.to_synapse_error()
except TimeoutError:
raise SynapseError(500, "Timed out contacting identity server")
@defer.inlineCallbacks
def requestMsisdnToken(
self,
id_server,
country,
phone_number,
client_secret,
send_attempt,
next_link=None,
):
"""
Request an external server send an SMS message on our behalf for the purposes of
threepid validation.
Args:
id_server (str): The identity server to proxy to
country (str): The country code of the phone number
phone_number (str): The number to send the message to
client_secret (str): The unique client_secret sends by the user
send_attempt (int): Which attempt this is
next_link: A link to redirect the user to once they submit the token
Returns:
The json response body from the server
"""
params = {
"country": country,
"phone_number": phone_number,
"client_secret": client_secret,
"send_attempt": send_attempt,
}
if next_link:
params["next_link"] = next_link
if self.hs.config.using_identity_server_from_trusted_list:
# Warn that a deprecated config option is in use
logger.warn(
'The config option "trust_identity_server_for_password_resets" '
'has been replaced by "account_threepid_delegate". '
"Please consult the sample config at docs/sample_config.yaml for "
"details and update your config file."
)
try:
data = yield self.http_client.post_json_get_json(
id_server + "/_matrix/identity/api/v1/validate/msisdn/requestToken",
params,
)
except HttpResponseException as e:
logger.info("Proxied requestToken failed: %r", e)
raise e.to_synapse_error()
except TimeoutError:
raise SynapseError(500, "Timed out contacting identity server")
assert self.hs.config.public_baseurl
# we need to tell the client to send the token back to us, since it doesn't
# otherwise know where to send it, so add submit_url response parameter
# (see also MSC2078)
data["submit_url"] = (
self.hs.config.public_baseurl
+ "_matrix/client/unstable/add_threepid/msisdn/submit_token"
)
return data
@defer.inlineCallbacks
def validate_threepid_session(self, client_secret, sid):
"""Validates a threepid session with only the client secret and session ID
Tries validating against any configured account_threepid_delegates as well as locally.
Args:
client_secret (str): A secret provided by the client
sid (str): The ID of the session
Returns:
Dict[str, str|int] if validation was successful, otherwise None
"""
# XXX: We shouldn't need to keep wrapping and unwrapping this value
threepid_creds = {"client_secret": client_secret, "sid": sid}
# We don't actually know which medium this 3PID is. Thus we first assume it's email,
# and if validation fails we try msisdn
validation_session = None
# Try to validate as email
if self.hs.config.threepid_behaviour_email == ThreepidBehaviour.REMOTE:
# Ask our delegated email identity server
validation_session = yield self.threepid_from_creds(
self.hs.config.account_threepid_delegate_email, threepid_creds
)
elif self.hs.config.threepid_behaviour_email == ThreepidBehaviour.LOCAL:
# Get a validated session matching these details
validation_session = yield self.store.get_threepid_validation_session(
"email", client_secret, sid=sid, validated=True
)
if validation_session:
return validation_session
# Try to validate as msisdn
if self.hs.config.account_threepid_delegate_msisdn:
# Ask our delegated msisdn identity server
validation_session = yield self.threepid_from_creds(
self.hs.config.account_threepid_delegate_msisdn, threepid_creds
)
return validation_session
@defer.inlineCallbacks
def proxy_msisdn_submit_token(self, id_server, client_secret, sid, token):
"""Proxy a POST submitToken request to an identity server for verification purposes
Args:
id_server (str): The identity server URL to contact
client_secret (str): Secret provided by the client
sid (str): The ID of the session
token (str): The verification token
Raises:
SynapseError: If we failed to contact the identity server
Returns:
Deferred[dict]: The response dict from the identity server
"""
body = {"client_secret": client_secret, "sid": sid, "token": token}
try:
return (
yield self.http_client.post_json_get_json(
id_server + "/_matrix/identity/api/v1/validate/msisdn/submitToken",
body,
)
)
except TimeoutError:
raise SynapseError(500, "Timed out contacting identity server")
except HttpResponseException as e:
logger.warning("Error contacting msisdn account_threepid_delegate: %s", e)
raise SynapseError(400, "Error contacting the identity server")
def create_id_access_token_header(id_access_token):
"""Create an Authorization header for passing to SimpleHttpClient as the header value
of an HTTP request.
Args:
id_access_token (str): An identity server access token.
Returns:
list[str]: The ascii-encoded bearer token encased in a list.
"""
# Prefix with Bearer
bearer_token = "Bearer %s" % id_access_token
# Encode headers to standard ascii
bearer_token.encode("ascii")
# Return as a list as that's how SimpleHttpClient takes header values
return [bearer_token]
class LookupAlgorithm:
"""
Supported hashing algorithms when performing a 3PID lookup.
SHA256 - Hashing an (address, medium, pepper) combo with sha256, then url-safe base64
encoding
NONE - Not performing any hashing. Simply sending an (address, medium) combo in plaintext
"""
SHA256 = "sha256"
NONE = "none"