forked-synapse/synapse/rest/client/media.py
Shay cf69f8d59b
Support MSC3916 by adding a federation /thumbnail endpoint and authenticated _matrix/client/v1/media/thumbnail endpoint (#17388)
[MSC3916](https://github.com/matrix-org/matrix-spec-proposals/pull/3916)
added the endpoints `_matrix/federation/v1/media/thumbnail` and the
authenticated `_matrix/client/v1/media/thumbnail`.

This PR implements those endpoints, along with stabilizing
`_matrix/client/v1/media/config` and
`_matrix/client/v1/media/preview_url`.

Complement tests are at
https://github.com/matrix-org/complement/pull/728
2024-07-08 10:11:20 +01:00

280 lines
9.6 KiB
Python

#
# This file is licensed under the Affero General Public License (AGPL) version 3.
#
# Copyright 2020 The Matrix.org Foundation C.I.C.
# Copyright 2015, 2016 OpenMarket Ltd
# Copyright (C) 2024 New Vector, Ltd
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# See the GNU Affero General Public License for more details:
# <https://www.gnu.org/licenses/agpl-3.0.html>.
#
# Originally licensed under the Apache License, Version 2.0:
# <http://www.apache.org/licenses/LICENSE-2.0>.
#
# [This file includes modifications made by New Vector Limited]
#
#
import logging
import re
from typing import Optional
from synapse.http.server import (
HttpServer,
respond_with_json,
respond_with_json_bytes,
set_corp_headers,
set_cors_headers,
)
from synapse.http.servlet import RestServlet, parse_integer, parse_string
from synapse.http.site import SynapseRequest
from synapse.media._base import (
DEFAULT_MAX_TIMEOUT_MS,
MAXIMUM_ALLOWED_MAX_TIMEOUT_MS,
respond_404,
)
from synapse.media.media_repository import MediaRepository
from synapse.media.media_storage import MediaStorage
from synapse.media.thumbnailer import ThumbnailProvider
from synapse.server import HomeServer
from synapse.util.stringutils import parse_and_validate_server_name
logger = logging.getLogger(__name__)
class PreviewURLServlet(RestServlet):
"""
Same as `GET /_matrix/media/r0/preview_url`, this endpoint provides a generic preview API
for URLs which outputs Open Graph (https://ogp.me/) responses (with some Matrix
specific additions).
This does have trade-offs compared to other designs:
* Pros:
* Simple and flexible; can be used by any clients at any point
* Cons:
* If each homeserver provides one of these independently, all the homeservers in a
room may needlessly DoS the target URI
* The URL metadata must be stored somewhere, rather than just using Matrix
itself to store the media.
* Matrix cannot be used to distribute the metadata between homeservers.
"""
PATTERNS = [re.compile(r"^/_matrix/client/v1/media/preview_url$")]
def __init__(
self,
hs: "HomeServer",
media_repo: "MediaRepository",
media_storage: MediaStorage,
):
super().__init__()
self.auth = hs.get_auth()
self.clock = hs.get_clock()
self.media_repo = media_repo
self.media_storage = media_storage
assert self.media_repo.url_previewer is not None
self.url_previewer = self.media_repo.url_previewer
async def on_GET(self, request: SynapseRequest) -> None:
requester = await self.auth.get_user_by_req(request)
url = parse_string(request, "url", required=True)
ts = parse_integer(request, "ts")
if ts is None:
ts = self.clock.time_msec()
og = await self.url_previewer.preview(url, requester.user, ts)
respond_with_json_bytes(request, 200, og, send_cors=True)
class MediaConfigResource(RestServlet):
PATTERNS = [re.compile(r"^/_matrix/client/v1/media/config$")]
def __init__(self, hs: "HomeServer"):
super().__init__()
config = hs.config
self.clock = hs.get_clock()
self.auth = hs.get_auth()
self.limits_dict = {"m.upload.size": config.media.max_upload_size}
async def on_GET(self, request: SynapseRequest) -> None:
await self.auth.get_user_by_req(request)
respond_with_json(request, 200, self.limits_dict, send_cors=True)
class ThumbnailResource(RestServlet):
PATTERNS = [
re.compile(
"/_matrix/client/v1/media/thumbnail/(?P<server_name>[^/]*)/(?P<media_id>[^/]*)$"
)
]
def __init__(
self,
hs: "HomeServer",
media_repo: "MediaRepository",
media_storage: MediaStorage,
):
super().__init__()
self.store = hs.get_datastores().main
self.media_repo = media_repo
self.media_storage = media_storage
self.dynamic_thumbnails = hs.config.media.dynamic_thumbnails
self._is_mine_server_name = hs.is_mine_server_name
self._server_name = hs.hostname
self.prevent_media_downloads_from = hs.config.media.prevent_media_downloads_from
self.thumbnailer = ThumbnailProvider(hs, media_repo, media_storage)
self.auth = hs.get_auth()
async def on_GET(
self, request: SynapseRequest, server_name: str, media_id: str
) -> None:
# Validate the server name, raising if invalid
parse_and_validate_server_name(server_name)
await self.auth.get_user_by_req(request)
set_cors_headers(request)
set_corp_headers(request)
width = parse_integer(request, "width", required=True)
height = parse_integer(request, "height", required=True)
method = parse_string(request, "method", "scale")
# TODO Parse the Accept header to get an prioritised list of thumbnail types.
m_type = "image/png"
max_timeout_ms = parse_integer(
request, "timeout_ms", default=DEFAULT_MAX_TIMEOUT_MS
)
max_timeout_ms = min(max_timeout_ms, MAXIMUM_ALLOWED_MAX_TIMEOUT_MS)
if self._is_mine_server_name(server_name):
if self.dynamic_thumbnails:
await self.thumbnailer.select_or_generate_local_thumbnail(
request,
media_id,
width,
height,
method,
m_type,
max_timeout_ms,
False,
)
else:
await self.thumbnailer.respond_local_thumbnail(
request,
media_id,
width,
height,
method,
m_type,
max_timeout_ms,
False,
)
self.media_repo.mark_recently_accessed(None, media_id)
else:
# Don't let users download media from configured domains, even if it
# is already downloaded. This is Trust & Safety tooling to make some
# media inaccessible to local users.
# See `prevent_media_downloads_from` config docs for more info.
if server_name in self.prevent_media_downloads_from:
respond_404(request)
return
ip_address = request.getClientAddress().host
remote_resp_function = (
self.thumbnailer.select_or_generate_remote_thumbnail
if self.dynamic_thumbnails
else self.thumbnailer.respond_remote_thumbnail
)
await remote_resp_function(
request,
server_name,
media_id,
width,
height,
method,
m_type,
max_timeout_ms,
ip_address,
True,
)
self.media_repo.mark_recently_accessed(server_name, media_id)
class DownloadResource(RestServlet):
PATTERNS = [
re.compile(
"/_matrix/client/v1/media/download/(?P<server_name>[^/]*)/(?P<media_id>[^/]*)(/(?P<file_name>[^/]*))?$"
)
]
def __init__(self, hs: "HomeServer", media_repo: "MediaRepository"):
super().__init__()
self.media_repo = media_repo
self._is_mine_server_name = hs.is_mine_server_name
self.auth = hs.get_auth()
async def on_GET(
self,
request: SynapseRequest,
server_name: str,
media_id: str,
file_name: Optional[str] = None,
) -> None:
# Validate the server name, raising if invalid
parse_and_validate_server_name(server_name)
await self.auth.get_user_by_req(request)
set_cors_headers(request)
set_corp_headers(request)
request.setHeader(
b"Content-Security-Policy",
b"sandbox;"
b" default-src 'none';"
b" script-src 'none';"
b" plugin-types application/pdf;"
b" style-src 'unsafe-inline';"
b" media-src 'self';"
b" object-src 'self';",
)
# Limited non-standard form of CSP for IE11
request.setHeader(b"X-Content-Security-Policy", b"sandbox;")
request.setHeader(b"Referrer-Policy", b"no-referrer")
max_timeout_ms = parse_integer(
request, "timeout_ms", default=DEFAULT_MAX_TIMEOUT_MS
)
max_timeout_ms = min(max_timeout_ms, MAXIMUM_ALLOWED_MAX_TIMEOUT_MS)
if self._is_mine_server_name(server_name):
await self.media_repo.get_local_media(
request, media_id, file_name, max_timeout_ms
)
else:
ip_address = request.getClientAddress().host
await self.media_repo.get_remote_media(
request,
server_name,
media_id,
file_name,
max_timeout_ms,
ip_address,
True,
)
def register_servlets(hs: "HomeServer", http_server: HttpServer) -> None:
media_repo = hs.get_media_repository()
if hs.config.media.url_preview_enabled:
PreviewURLServlet(hs, media_repo, media_repo.media_storage).register(
http_server
)
MediaConfigResource(hs).register(http_server)
ThumbnailResource(hs, media_repo, media_repo.media_storage).register(http_server)
DownloadResource(hs, media_repo).register(http_server)