add a tonne of docstring; make upload_room_keys properly assert version

This commit is contained in:
Matthew Hodgson 2017-12-27 23:37:44 +00:00 committed by Hubert Chathi
parent 9f0791b7bd
commit 14b3da63a3
2 changed files with 113 additions and 9 deletions

View File

@ -42,7 +42,16 @@ class E2eRoomKeysHandler(object):
self._upload_linearizer = Linearizer("upload_room_keys_lock")
@defer.inlineCallbacks
def get_room_keys(self, user_id, version, room_id, session_id):
def get_room_keys(self, user_id, version, room_id=None, session_id=None):
"""Bulk get the E2E room keys for a given backup, optionally filtered to a given
room, or a given session.
See EndToEndRoomKeyStore.get_e2e_room_keys for full details.
Returns:
A deferred list of dicts giving the session_data and message metadata for
these room keys.
"""
# we deliberately take the lock to get keys so that changing the version
# works atomically
with (yield self._upload_linearizer.queue(user_id)):
@ -52,20 +61,56 @@ class E2eRoomKeysHandler(object):
defer.returnValue(results)
@defer.inlineCallbacks
def delete_room_keys(self, user_id, version, room_id, session_id):
def delete_room_keys(self, user_id, version, room_id=None, session_id=None):
"""Bulk delete the E2E room keys for a given backup, optionally filtered to a given
room or a given session.
See EndToEndRoomKeyStore.delete_e2e_room_keys for full details.
Returns:
A deferred of the deletion transaction
"""
# lock for consistency with uploading
with (yield self._upload_linearizer.queue(user_id)):
yield self.store.delete_e2e_room_keys(user_id, version, room_id, session_id)
@defer.inlineCallbacks
def upload_room_keys(self, user_id, version, room_keys):
"""Bulk upload a list of room keys into a given backup version, asserting
that the given version is the current backup version. room_keys are merged
into the current backup as described in RoomKeysServlet.on_PUT().
Args:
user_id(str): the user whose backup we're setting
version(str): the version ID of the backup we're updating
room_keys(dict): a nested dict describing the room_keys we're setting:
{
"rooms": {
"!abc:matrix.org": {
"sessions": {
"c0ff33": {
"first_message_index": 1,
"forwarded_count": 1,
"is_verified": false,
"session_data": "SSBBTSBBIEZJU0gK"
}
}
}
}
}
Raises:
SynapseError: with code 404 if there are no versions defined
RoomKeysVersionError: if the uploaded version is not the current version
"""
# TODO: Validate the JSON to make sure it has the right keys.
# XXX: perhaps we should use a finer grained lock here?
with (yield self._upload_linearizer.queue(user_id)):
# Check that the version we're trying to upload is the current version
try:
version_info = yield self.get_version_info(user_id, version)
version_info = yield self.get_current_version_info(user_id)
except StoreError as e:
if e.code == 404:
raise SynapseError(404, "Version '%s' not found" % (version,))
@ -87,6 +132,17 @@ class E2eRoomKeysHandler(object):
@defer.inlineCallbacks
def _upload_room_key(self, user_id, version, room_id, session_id, room_key):
"""Upload a given room_key for a given room and session into a given
version of the backup. Merges the key with any which might already exist.
Args:
user_id(str): the user whose backup we're setting
version(str): the version ID of the backup we're updating
room_id(str): the ID of the room whose keys we're setting
session_id(str): the session whose room_key we're setting
room_key(dict): the room_key being set
"""
# get the room_key for this particular row
current_room_key = None
try:
@ -138,6 +194,23 @@ class E2eRoomKeysHandler(object):
@defer.inlineCallbacks
def create_version(self, user_id, version_info):
"""Create a new backup version. This automatically becomes the new
backup version for the user's keys; previous backups will no longer be
writeable to.
Args:
user_id(str): the user whose backup version we're creating
version_info(dict): metadata about the new version being created
{
"algorithm": "m.megolm_backup.v1",
"auth_data": "dGhpcyBzaG91bGQgYWN0dWFsbHkgYmUgZW5jcnlwdGVkIGpzb24K"
}
Returns:
A deferred of a string that gives the new version number.
"""
# TODO: Validate the JSON to make sure it has the right keys.
# lock everyone out until we've switched version
@ -148,14 +221,36 @@ class E2eRoomKeysHandler(object):
defer.returnValue(new_version)
@defer.inlineCallbacks
def get_version_info(self, user_id, version):
def get_current_version_info(self, user_id):
"""Get the user's current backup version.
Args:
user_id(str): the user whose current backup version we're querying
Raises:
StoreError: code 404 if there is no current backup version
Returns:
A deferred of a info dict that gives the info about the new version.
{
"algorithm": "m.megolm_backup.v1",
"auth_data": "dGhpcyBzaG91bGQgYWN0dWFsbHkgYmUgZW5jcnlwdGVkIGpzb24K"
}
"""
with (yield self._upload_linearizer.queue(user_id)):
results = yield self.store.get_e2e_room_keys_version_info(
user_id, version
)
results = yield self.store.get_e2e_room_keys_version_info(user_id)
defer.returnValue(results)
@defer.inlineCallbacks
def delete_version(self, user_id, version):
"""Deletes a given version of the user's e2e_room_keys backup
Args:
user_id(str): the user whose current backup version we're deleting
version(str): the version id of the backup being deleted
Raises:
StoreError: code 404 if this backup version doesn't exist
"""
with (yield self._upload_linearizer.queue(user_id)):
yield self.store.delete_e2e_room_keys_version(user_id, version)

View File

@ -47,7 +47,7 @@ class RoomKeysServlet(RestServlet):
room_id: the ID of the room the keys are for (optional)
session_id: the ID for the E2E room keys for the room (optional)
version: the version of the user's backup which this data is for.
the version must already have been created via the /change_secret API.
the version must already have been created via the /room_keys/version API.
Each session has:
* first_message_index: a numeric index indicating the oldest message
@ -59,6 +59,9 @@ class RoomKeysServlet(RestServlet):
* session_data: base64-encrypted data describing the session.
Returns 200 OK on success with body {}
Returns 403 Forbidden if the version in question is not the most recently
created version (i.e. if this is an old client trying to write to a stale backup)
Returns 404 Not Found if the version in question doesn't exist
The API is designed to be otherwise agnostic to the room_key encryption
algorithm being used. Sessions are merged with existing ones in the
@ -251,6 +254,9 @@ class RoomKeysVersionServlet(RestServlet):
changes the encryption key for their backups, ensuring that backups
encrypted with different keys don't collide.
It takes out an exclusive lock on this user's room_key backups, to ensure
clients only upload to the current backup.
The algorithm passed in the version info is a reverse-DNS namespaced
identifier to describe the format of the encrypted backupped keys.
@ -292,6 +298,9 @@ class RoomKeysVersionServlet(RestServlet):
Retrieve the version information about a given version of the user's
room_keys backup.
It takes out an exclusive lock on this user's room_key backups, to ensure
clients only upload to the current backup.
GET /room_keys/version/12345 HTTP/1.1
{
"algorithm": "m.megolm_backup.v1",