Merge pull request #3276 from matrix-org/dbkr/unbind

Remove email addresses / phone numbers from ID servers when they're removed from synapse

3 files changed, 82 insertions, 2 deletions

diff --git a/synapse/handlers/auth.py b/synapse/handlers/auth.py
index 3c0051586d..912136534d 100644
--- a/synapse/handlers/auth.py
+++ b/synapse/handlers/auth.py
@@ -825,6 +825,15 @@ class AuthHandler(BaseHandler):
         if medium == 'email':
             address = address.lower()
 
+        identity_handler = self.hs.get_handlers().identity_handler
+        yield identity_handler.unbind_threepid(
+            user_id,
+            {
+                'medium': medium,
+                'address': address,
+            },
+        )
+
         ret = yield self.store.user_delete_threepid(
             user_id, medium, address,
         )
diff --git a/synapse/handlers/deactivate_account.py b/synapse/handlers/deactivate_account.py
index c5e92f6214..8ec5ba2012 100644
--- a/synapse/handlers/deactivate_account.py
+++ b/synapse/handlers/deactivate_account.py
@@ -17,6 +17,7 @@ from twisted.internet import defer, reactor
 from ._base import BaseHandler
 from synapse.types import UserID, create_requester
 from synapse.util.logcontext import run_in_background
+from synapse.api.errors import SynapseError
 
 import logging
 
@@ -30,6 +31,7 @@ class DeactivateAccountHandler(BaseHandler):
         self._auth_handler = hs.get_auth_handler()
         self._device_handler = hs.get_device_handler()
         self._room_member_handler = hs.get_room_member_handler()
+        self._identity_handler = hs.get_handlers().identity_handler
         self.user_directory_handler = hs.get_user_directory_handler()
 
         # Flag that indicates whether the process to part users from rooms is running
@@ -52,14 +54,35 @@ class DeactivateAccountHandler(BaseHandler):
         # FIXME: Theoretically there is a race here wherein user resets
         # password using threepid.
 
-        # first delete any devices belonging to the user, which will also
+        # delete threepids first. We remove these from the IS so if this fails,
+        # leave the user still active so they can try again.
+        # Ideally we would prevent password resets and then do this in the
+        # background thread.
+        threepids = yield self.store.user_get_threepids(user_id)
+        for threepid in threepids:
+            try:
+                yield self._identity_handler.unbind_threepid(
+                    user_id,
+                    {
+                        'medium': threepid['medium'],
+                        'address': threepid['address'],
+                    },
+                )
+            except Exception:
+                # Do we want this to be a fatal error or should we carry on?
+                logger.exception("Failed to remove threepid from ID server")
+                raise SynapseError(400, "Failed to remove threepid from ID server")
+            yield self.store.user_delete_threepid(
+                user_id, threepid['medium'], threepid['address'],
+            )
+
+        # delete any devices belonging to the user, which will also
         # delete corresponding access tokens.
         yield self._device_handler.delete_all_devices_for_user(user_id)
         # then delete any remaining access tokens which weren't associated with
         # a device.
         yield self._auth_handler.delete_access_tokens_for_user(user_id)
 
-        yield self.store.user_delete_threepids(user_id)
         yield self.store.user_set_password_hash(user_id, None)
 
         # Add the user to a table of users pending deactivation (ie.
diff --git a/synapse/handlers/identity.py b/synapse/handlers/identity.py
index 91a0898860..529400955d 100644
--- a/synapse/handlers/identity.py
+++ b/synapse/handlers/identity.py
@@ -1,6 +1,7 @@
 # -*- 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.
@@ -38,6 +39,7 @@ class IdentityHandler(BaseHandler):
         super(IdentityHandler, self).__init__(hs)
 
         self.http_client = hs.get_simple_http_client()
+        self.federation_http_client = hs.get_http_client()
 
         self.trusted_id_servers = set(hs.config.trusted_third_party_id_servers)
         self.trust_any_id_server_just_for_testing_do_not_use = (
@@ -139,6 +141,52 @@ class IdentityHandler(BaseHandler):
         defer.returnValue(data)
 
     @defer.inlineCallbacks
+    def unbind_threepid(self, mxid, threepid):
+        """
+        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
+
+        Returns:
+            Deferred[bool]: True on success, otherwise False
+        """
+        logger.debug("unbinding threepid %r from %s", threepid, mxid)
+        if not self.trusted_id_servers:
+            logger.warn("Can't unbind threepid: no trusted ID servers set in config")
+            defer.returnValue(False)
+
+        # We don't track what ID server we added 3pids on (perhaps we ought to)
+        # but we assume that any of the servers in the trusted list are in the
+        # same ID server federation, so we can pick any one of them to send the
+        # deletion request to.
+        id_server = next(iter(self.trusted_id_servers))
+
+        url = "https://%s/_matrix/identity/api/v1/3pid/unbind" % (id_server,)
+        content = {
+            "mxid": mxid,
+            "threepid": threepid,
+        }
+        headers = {}
+        # 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.
+        self.federation_http_client.sign_request(
+            destination=None,
+            method='POST',
+            url_bytes='/_matrix/identity/api/v1/3pid/unbind'.encode('ascii'),
+            headers_dict=headers,
+            content=content,
+            destination_is=id_server,
+        )
+        yield self.http_client.post_json_get_json(
+            url,
+            content,
+            headers,
+        )
+        defer.returnValue(True)
+
+    @defer.inlineCallbacks
     def requestEmailToken(self, id_server, email, client_secret, send_attempt, **kwargs):
         yield run_on_reactor()