diff --git a/synapse/http/endpoint.py b/synapse/http/endpoint.py
index 80da870584..1b1123b292 100644
--- a/synapse/http/endpoint.py
+++ b/synapse/http/endpoint.py
@@ -12,6 +12,8 @@
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
+import re
+
from twisted.internet.endpoints import HostnameEndpoint, wrapClientTLS
from twisted.internet import defer
from twisted.internet.error import ConnectError
@@ -38,6 +40,71 @@ _Server = collections.namedtuple(
)
+def parse_server_name(server_name):
+ """Split a server name into host/port parts.
+
+ Args:
+ server_name (str): server name to parse
+
+ Returns:
+ Tuple[str, int|None]: host/port parts.
+
+ Raises:
+ ValueError if the server name could not be parsed.
+ """
+ try:
+ if server_name[-1] == ']':
+ # ipv6 literal, hopefully
+ return server_name, None
+
+ domain_port = server_name.rsplit(":", 1)
+ domain = domain_port[0]
+ port = int(domain_port[1]) if domain_port[1:] else None
+ return domain, port
+ except Exception:
+ raise ValueError("Invalid server name '%s'" % server_name)
+
+
+VALID_HOST_REGEX = re.compile(
+ "\\A[0-9a-zA-Z.-]+\\Z",
+)
+
+
+def parse_and_validate_server_name(server_name):
+ """Split a server name into host/port parts and do some basic validation.
+
+ Args:
+ server_name (str): server name to parse
+
+ Returns:
+ Tuple[str, int|None]: host/port parts.
+
+ Raises:
+ ValueError if the server name could not be parsed.
+ """
+ host, port = parse_server_name(server_name)
+
+ # these tests don't need to be bulletproof as we'll find out soon enough
+ # if somebody is giving us invalid data. What we *do* need is to be sure
+ # that nobody is sneaking IP literals in that look like hostnames, etc.
+
+ # look for ipv6 literals
+ if host[0] == '[':
+ if host[-1] != ']':
+ raise ValueError("Mismatched [...] in server name '%s'" % (
+ server_name,
+ ))
+ return host, port
+
+ # otherwise it should only be alphanumerics.
+ if not VALID_HOST_REGEX.match(host):
+ raise ValueError("Server name '%s' contains invalid characters" % (
+ server_name,
+ ))
+
+ return host, port
+
+
def matrix_federation_endpoint(reactor, destination, ssl_context_factory=None,
timeout=None):
"""Construct an endpoint for the given matrix destination.
@@ -50,9 +117,7 @@ def matrix_federation_endpoint(reactor, destination, ssl_context_factory=None,
timeout (int): connection timeout in seconds
"""
- domain_port = destination.split(":")
- domain = domain_port[0]
- port = int(domain_port[1]) if domain_port[1:] else None
+ domain, port = parse_server_name(destination)
endpoint_kw_args = {}
|