summary refs log tree commit diff
path: root/synapse
diff options
context:
space:
mode:
authorRichard van der Hoff <1389908+richvdh@users.noreply.github.com>2019-01-24 09:34:44 +0000
committerGitHub <noreply@github.com>2019-01-24 09:34:44 +0000
commit97fd29c019ae92cd3dc0635de249acfc9c892340 (patch)
tree2a85a700325501b61ebc41fce8514ade812da8bc /synapse
parentMerge pull request #4445 from matrix-org/anoa/user_dir_develop_backport (diff)
downloadsynapse-97fd29c019ae92cd3dc0635de249acfc9c892340.tar.xz
Don't send IP addresses as SNI (#4452)
The problem here is that we have cut-and-pasted an impl from Twisted, and then
failed to maintain it. It was fixed in Twisted in
https://github.com/twisted/twisted/pull/1047/files; let's do the same here.
Diffstat (limited to 'synapse')
-rw-r--r--synapse/crypto/context_factory.py15
1 files changed, 12 insertions, 3 deletions
diff --git a/synapse/crypto/context_factory.py b/synapse/crypto/context_factory.py
index 6ba3eca7b2..286ad80100 100644
--- a/synapse/crypto/context_factory.py
+++ b/synapse/crypto/context_factory.py
@@ -17,6 +17,7 @@ from zope.interface import implementer
 
 from OpenSSL import SSL, crypto
 from twisted.internet._sslverify import _defaultCurveName
+from twisted.internet.abstract import isIPAddress, isIPv6Address
 from twisted.internet.interfaces import IOpenSSLClientConnectionCreator
 from twisted.internet.ssl import CertificateOptions, ContextFactory
 from twisted.python.failure import Failure
@@ -98,8 +99,14 @@ class ClientTLSOptions(object):
 
     def __init__(self, hostname, ctx):
         self._ctx = ctx
-        self._hostname = hostname
-        self._hostnameBytes = _idnaBytes(hostname)
+
+        if isIPAddress(hostname) or isIPv6Address(hostname):
+            self._hostnameBytes = hostname.encode('ascii')
+            self._sendSNI = False
+        else:
+            self._hostnameBytes = _idnaBytes(hostname)
+            self._sendSNI = True
+
         ctx.set_info_callback(
             _tolerateErrors(self._identityVerifyingInfoCallback)
         )
@@ -111,7 +118,9 @@ class ClientTLSOptions(object):
         return connection
 
     def _identityVerifyingInfoCallback(self, connection, where, ret):
-        if where & SSL.SSL_CB_HANDSHAKE_START:
+        # Literal IPv4 and IPv6 addresses are not permitted
+        # as host names according to the RFCs
+        if where & SSL.SSL_CB_HANDSHAKE_START and self._sendSNI:
             connection.set_tlsext_host_name(self._hostnameBytes)