1# Copyright 2018 New Vector Ltd
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#     http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14
15import logging
16from typing import TYPE_CHECKING, Optional
17
18from twisted.web.resource import Resource
19from twisted.web.server import Request
20
21from synapse.http.server import set_cors_headers
22from synapse.types import JsonDict
23from synapse.util import json_encoder
24from synapse.util.stringutils import parse_server_name
25
26if TYPE_CHECKING:
27    from synapse.server import HomeServer
28
29logger = logging.getLogger(__name__)
30
31
32class WellKnownBuilder:
33    def __init__(self, hs: "HomeServer"):
34        self._config = hs.config
35
36    def get_well_known(self) -> Optional[JsonDict]:
37        if not self._config.server.serve_client_wellknown:
38            return None
39
40        result = {"m.homeserver": {"base_url": self._config.server.public_baseurl}}
41
42        if self._config.registration.default_identity_server:
43            result["m.identity_server"] = {
44                "base_url": self._config.registration.default_identity_server
45            }
46
47        return result
48
49
50class ClientWellKnownResource(Resource):
51    """A Twisted web resource which renders the .well-known/matrix/client file"""
52
53    isLeaf = 1
54
55    def __init__(self, hs: "HomeServer"):
56        Resource.__init__(self)
57        self._well_known_builder = WellKnownBuilder(hs)
58
59    def render_GET(self, request: Request) -> bytes:
60        set_cors_headers(request)
61        r = self._well_known_builder.get_well_known()
62        if not r:
63            request.setResponseCode(404)
64            request.setHeader(b"Content-Type", b"text/plain")
65            return b".well-known not available"
66
67        logger.debug("returning: %s", r)
68        request.setHeader(b"Content-Type", b"application/json")
69        return json_encoder.encode(r).encode("utf-8")
70
71
72class ServerWellKnownResource(Resource):
73    """Resource for .well-known/matrix/server, redirecting to port 443"""
74
75    isLeaf = 1
76
77    def __init__(self, hs: "HomeServer"):
78        super().__init__()
79        self._serve_server_wellknown = hs.config.server.serve_server_wellknown
80
81        host, port = parse_server_name(hs.config.server.server_name)
82
83        # If we've got this far, then https://<server_name>/ must route to us, so
84        # we just redirect the traffic to port 443 instead of 8448.
85        if port is None:
86            port = 443
87
88        self._response = json_encoder.encode({"m.server": f"{host}:{port}"}).encode(
89            "utf-8"
90        )
91
92    def render_GET(self, request: Request) -> bytes:
93        if not self._serve_server_wellknown:
94            request.setResponseCode(404)
95            request.setHeader(b"Content-Type", b"text/plain")
96            return b"404. Is anything ever truly *well* known?\n"
97
98        request.setHeader(b"Content-Type", b"application/json")
99        return self._response
100
101
102def well_known_resource(hs: "HomeServer") -> Resource:
103    """Returns a Twisted web resource which handles '.well-known' requests"""
104    res = Resource()
105    matrix_resource = Resource()
106    res.putChild(b"matrix", matrix_resource)
107
108    matrix_resource.putChild(b"server", ServerWellKnownResource(hs))
109    matrix_resource.putChild(b"client", ClientWellKnownResource(hs))
110
111    return res
112