Merge pull request #990 from matrix-org/erikj/fed_vers

Add federation /version API

1 files changed, 72 insertions, 41 deletions

diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py
index 0bc6e0801d..37c0d4fbc4 100644
--- a/synapse/federation/transport/server.py
+++ b/synapse/federation/transport/server.py
@@ -18,13 +18,14 @@ from twisted.internet import defer
 from synapse.api.urls import FEDERATION_PREFIX as PREFIX
 from synapse.api.errors import Codes, SynapseError
 from synapse.http.server import JsonResource
-from synapse.http.servlet import parse_json_object_from_request, parse_string
+from synapse.http.servlet import parse_json_object_from_request
 from synapse.util.ratelimitutils import FederationRateLimiter
+from synapse.util.versionstring import get_version_string
 
 import functools
 import logging
-import simplejson as json
 import re
+import synapse
 
 
 logger = logging.getLogger(__name__)
@@ -60,6 +61,16 @@ class TransportLayerServer(JsonResource):
         )
 
 
+class AuthenticationError(SynapseError):
+    """There was a problem authenticating the request"""
+    pass
+
+
+class NoAuthenticationError(AuthenticationError):
+    """The request had no authentication information"""
+    pass
+
+
 class Authenticator(object):
     def __init__(self, hs):
         self.keyring = hs.get_keyring()
@@ -67,7 +78,7 @@ class Authenticator(object):
 
     # A method just so we can pass 'self' as the authenticator to the Servlets
     @defer.inlineCallbacks
-    def authenticate_request(self, request):
+    def authenticate_request(self, request, content):
         json_request = {
             "method": request.method,
             "uri": request.uri,
@@ -75,17 +86,10 @@ class Authenticator(object):
             "signatures": {},
         }
 
-        content = None
-        origin = None
+        if content is not None:
+            json_request["content"] = content
 
-        if request.method in ["PUT", "POST"]:
-            # TODO: Handle other method types? other content types?
-            try:
-                content_bytes = request.content.read()
-                content = json.loads(content_bytes)
-                json_request["content"] = content
-            except:
-                raise SynapseError(400, "Unable to parse JSON", Codes.BAD_JSON)
+        origin = None
 
         def parse_auth_header(header_str):
             try:
@@ -103,14 +107,14 @@ class Authenticator(object):
                 sig = strip_quotes(param_dict["sig"])
                 return (origin, key, sig)
             except:
-                raise SynapseError(
+                raise AuthenticationError(
                     400, "Malformed Authorization header", Codes.UNAUTHORIZED
                 )
 
         auth_headers = request.requestHeaders.getRawHeaders(b"Authorization")
 
         if not auth_headers:
-            raise SynapseError(
+            raise NoAuthenticationError(
                 401, "Missing Authorization headers", Codes.UNAUTHORIZED,
             )
 
@@ -121,7 +125,7 @@ class Authenticator(object):
                 json_request["signatures"].setdefault(origin, {})[key] = sig
 
         if not json_request["signatures"]:
-            raise SynapseError(
+            raise NoAuthenticationError(
                 401, "Missing Authorization headers", Codes.UNAUTHORIZED,
             )
 
@@ -130,10 +134,12 @@ class Authenticator(object):
         logger.info("Request from %s", origin)
         request.authenticated_entity = origin
 
-        defer.returnValue((origin, content))
+        defer.returnValue(origin)
 
 
 class BaseFederationServlet(object):
+    REQUIRE_AUTH = True
+
     def __init__(self, handler, authenticator, ratelimiter, server_name,
                  room_list_handler):
         self.handler = handler
@@ -141,29 +147,46 @@ class BaseFederationServlet(object):
         self.ratelimiter = ratelimiter
         self.room_list_handler = room_list_handler
 
-    def _wrap(self, code):
+    def _wrap(self, func):
         authenticator = self.authenticator
         ratelimiter = self.ratelimiter
 
         @defer.inlineCallbacks
-        @functools.wraps(code)
-        def new_code(request, *args, **kwargs):
+        @functools.wraps(func)
+        def new_func(request, *args, **kwargs):
+            content = None
+            if request.method in ["PUT", "POST"]:
+                # TODO: Handle other method types? other content types?
+                content = parse_json_object_from_request(request)
+
             try:
-                (origin, content) = yield authenticator.authenticate_request(request)
+                origin = yield authenticator.authenticate_request(request, content)
+            except NoAuthenticationError:
+                origin = None
+                if self.REQUIRE_AUTH:
+                    logger.exception("authenticate_request failed")
+                    raise
+            except:
+                logger.exception("authenticate_request failed")
+                raise
+
+            if origin:
                 with ratelimiter.ratelimit(origin) as d:
                     yield d
-                    response = yield code(
+                    response = yield func(
                         origin, content, request.args, *args, **kwargs
                     )
-            except:
-                logger.exception("authenticate_request failed")
-                raise
+            else:
+                response = yield func(
+                    origin, content, request.args, *args, **kwargs
+                )
+
             defer.returnValue(response)
 
         # Extra logic that functools.wraps() doesn't finish
-        new_code.__self__ = code.__self__
+        new_func.__self__ = func.__self__
 
-        return new_code
+        return new_func
 
     def register(self, server):
         pattern = re.compile("^" + PREFIX + self.PATH + "$")
@@ -429,9 +452,10 @@ class FederationGetMissingEventsServlet(BaseFederationServlet):
 class On3pidBindServlet(BaseFederationServlet):
     PATH = "/3pid/onbind"
 
+    REQUIRE_AUTH = False
+
     @defer.inlineCallbacks
-    def on_POST(self, request):
-        content = parse_json_object_from_request(request)
+    def on_POST(self, origin, content, query):
         if "invites" in content:
             last_exception = None
             for invite in content["invites"]:
@@ -453,11 +477,6 @@ class On3pidBindServlet(BaseFederationServlet):
                 raise last_exception
         defer.returnValue((200, {}))
 
-    # Avoid doing remote HS authorization checks which are done by default by
-    # BaseFederationServlet.
-    def _wrap(self, code):
-        return code
-
 
 class OpenIdUserInfo(BaseFederationServlet):
     """
@@ -478,9 +497,11 @@ class OpenIdUserInfo(BaseFederationServlet):
 
     PATH = "/openid/userinfo"
 
+    REQUIRE_AUTH = False
+
     @defer.inlineCallbacks
-    def on_GET(self, request):
-        token = parse_string(request, "access_token")
+    def on_GET(self, origin, content, query):
+        token = query.get("access_token", [None])[0]
         if token is None:
             defer.returnValue((401, {
                 "errcode": "M_MISSING_TOKEN", "error": "Access Token required"
@@ -497,11 +518,6 @@ class OpenIdUserInfo(BaseFederationServlet):
 
         defer.returnValue((200, {"sub": user_id}))
 
-    # Avoid doing remote HS authorization checks which are done by default by
-    # BaseFederationServlet.
-    def _wrap(self, code):
-        return code
-
 
 class PublicRoomList(BaseFederationServlet):
     """
@@ -542,6 +558,20 @@ class PublicRoomList(BaseFederationServlet):
         defer.returnValue((200, data))
 
 
+class FederationVersionServlet(BaseFederationServlet):
+    PATH = "/version"
+
+    REQUIRE_AUTH = False
+
+    def on_GET(self, origin, content, query):
+        return defer.succeed((200, {
+            "server": {
+                "name": "Synapse",
+                "version": get_version_string(synapse)
+            },
+        }))
+
+
 SERVLET_CLASSES = (
     FederationSendServlet,
     FederationPullServlet,
@@ -565,6 +595,7 @@ SERVLET_CLASSES = (
     On3pidBindServlet,
     OpenIdUserInfo,
     PublicRoomList,
+    FederationVersionServlet,
 )