# Copyright 2018 New Vector Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# 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 json
import os
import re
from twisted.internet._resolver import HostResolution
from twisted.internet.address import IPv4Address, IPv6Address
from twisted.internet.error import DNSLookupError
from twisted.test.proto_helpers import AccumulatingProtocol
from synapse.config.oembed import OEmbedEndpointConfig
from tests import unittest
from tests.server import FakeTransport
from tests.test_utils import SMALL_PNG
try:
import lxml
except ImportError:
lxml = None
class URLPreviewTests(unittest.HomeserverTestCase):
if not lxml:
skip = "url preview feature requires lxml"
hijack_auth = True
user_id = "@test:user"
end_content = (
b"
"
b''
b''
b""
)
def make_homeserver(self, reactor, clock):
config = self.default_config()
config["url_preview_enabled"] = True
config["max_spider_size"] = 9999999
config["url_preview_ip_range_blacklist"] = (
"192.168.1.1",
"1.0.0.0/8",
"3fff:ffff:ffff:ffff:ffff:ffff:ffff:ffff",
"2001:800::/21",
)
config["url_preview_ip_range_whitelist"] = ("1.1.1.1",)
config["url_preview_url_blacklist"] = []
config["url_preview_accept_language"] = [
"en-UK",
"en-US;q=0.9",
"fr;q=0.8",
"*;q=0.7",
]
self.storage_path = self.mktemp()
self.media_store_path = self.mktemp()
os.mkdir(self.storage_path)
os.mkdir(self.media_store_path)
config["media_store_path"] = self.media_store_path
provider_config = {
"module": "synapse.rest.media.v1.storage_provider.FileStorageProviderBackend",
"store_local": True,
"store_synchronous": False,
"store_remote": True,
"config": {"directory": self.storage_path},
}
config["media_storage_providers"] = [provider_config]
hs = self.setup_test_homeserver(config=config)
# After the hs is created, modify the parsed oEmbed config (to avoid
# messing with files).
#
# Note that HTTP URLs are used to avoid having to deal with TLS in tests.
hs.config.oembed.oembed_patterns = [
OEmbedEndpointConfig(
api_endpoint="http://publish.twitter.com/oembed",
url_patterns=[
re.compile(r"http://twitter\.com/.+/status/.+"),
],
formats=None,
),
OEmbedEndpointConfig(
api_endpoint="http://www.hulu.com/api/oembed.{format}",
url_patterns=[
re.compile(r"http://www\.hulu\.com/watch/.+"),
],
formats=["json"],
),
]
return hs
def prepare(self, reactor, clock, hs):
self.media_repo = hs.get_media_repository_resource()
self.preview_url = self.media_repo.children[b"preview_url"]
self.lookups = {}
class Resolver:
def resolveHostName(
_self,
resolutionReceiver,
hostName,
portNumber=0,
addressTypes=None,
transportSemantics="TCP",
):
resolution = HostResolution(hostName)
resolutionReceiver.resolutionBegan(resolution)
if hostName not in self.lookups:
raise DNSLookupError("OH NO")
for i in self.lookups[hostName]:
resolutionReceiver.addressResolved(i[0]("TCP", i[1], portNumber))
resolutionReceiver.resolutionComplete()
return resolutionReceiver
self.reactor.nameResolver = Resolver()
def create_test_resource(self):
return self.hs.get_media_repository_resource()
def test_cache_returns_correct_type(self):
self.lookups["matrix.org"] = [(IPv4Address, "10.1.2.3")]
channel = self.make_request(
"GET",
"preview_url?url=http://matrix.org",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\nContent-Type: text/html\r\n\r\n"
% (len(self.end_content),)
+ self.end_content
)
self.pump()
self.assertEqual(channel.code, 200)
self.assertEqual(
channel.json_body, {"og:title": "~matrix~", "og:description": "hi"}
)
# Check the cache returns the correct response
channel = self.make_request(
"GET", "preview_url?url=http://matrix.org", shorthand=False
)
# Check the cache response has the same content
self.assertEqual(channel.code, 200)
self.assertEqual(
channel.json_body, {"og:title": "~matrix~", "og:description": "hi"}
)
# Clear the in-memory cache
self.assertIn("http://matrix.org", self.preview_url._cache)
self.preview_url._cache.pop("http://matrix.org")
self.assertNotIn("http://matrix.org", self.preview_url._cache)
# Check the database cache returns the correct response
channel = self.make_request(
"GET", "preview_url?url=http://matrix.org", shorthand=False
)
# Check the cache response has the same content
self.assertEqual(channel.code, 200)
self.assertEqual(
channel.json_body, {"og:title": "~matrix~", "og:description": "hi"}
)
def test_non_ascii_preview_httpequiv(self):
self.lookups["matrix.org"] = [(IPv4Address, "10.1.2.3")]
end_content = (
b""
b''
b''
b''
b""
)
channel = self.make_request(
"GET",
"preview_url?url=http://matrix.org",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n"
b'Content-Type: text/html; charset="utf8"\r\n\r\n'
)
% (len(end_content),)
+ end_content
)
self.pump()
self.assertEqual(channel.code, 200)
self.assertEqual(channel.json_body["og:title"], "\u0434\u043a\u0430")
def test_non_ascii_preview_content_type(self):
self.lookups["matrix.org"] = [(IPv4Address, "10.1.2.3")]
end_content = (
b""
b''
b''
b""
)
channel = self.make_request(
"GET",
"preview_url?url=http://matrix.org",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n"
b'Content-Type: text/html; charset="windows-1251"\r\n\r\n'
)
% (len(end_content),)
+ end_content
)
self.pump()
self.assertEqual(channel.code, 200)
self.assertEqual(channel.json_body["og:title"], "\u0434\u043a\u0430")
def test_overlong_title(self):
self.lookups["matrix.org"] = [(IPv4Address, "10.1.2.3")]
end_content = (
b""
b"" + b"x" * 2000 + b""
b''
b""
)
channel = self.make_request(
"GET",
"preview_url?url=http://matrix.org",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n"
b'Content-Type: text/html; charset="windows-1251"\r\n\r\n'
)
% (len(end_content),)
+ end_content
)
self.pump()
self.assertEqual(channel.code, 200)
res = channel.json_body
# We should only see the `og:description` field, as `title` is too long and should be stripped out
self.assertCountEqual(["og:description"], res.keys())
def test_ipaddr(self):
"""
IP addresses can be previewed directly.
"""
self.lookups["example.com"] = [(IPv4Address, "10.1.2.3")]
channel = self.make_request(
"GET",
"preview_url?url=http://example.com",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\nContent-Type: text/html\r\n\r\n"
% (len(self.end_content),)
+ self.end_content
)
self.pump()
self.assertEqual(channel.code, 200)
self.assertEqual(
channel.json_body, {"og:title": "~matrix~", "og:description": "hi"}
)
def test_blacklisted_ip_specific(self):
"""
Blacklisted IP addresses, found via DNS, are not spidered.
"""
self.lookups["example.com"] = [(IPv4Address, "192.168.1.1")]
channel = self.make_request(
"GET", "preview_url?url=http://example.com", shorthand=False
)
# No requests made.
self.assertEqual(len(self.reactor.tcpClients), 0)
self.assertEqual(channel.code, 502)
self.assertEqual(
channel.json_body,
{
"errcode": "M_UNKNOWN",
"error": "DNS resolution failure during URL preview generation",
},
)
def test_blacklisted_ip_range(self):
"""
Blacklisted IP ranges, IPs found over DNS, are not spidered.
"""
self.lookups["example.com"] = [(IPv4Address, "1.1.1.2")]
channel = self.make_request(
"GET", "preview_url?url=http://example.com", shorthand=False
)
self.assertEqual(channel.code, 502)
self.assertEqual(
channel.json_body,
{
"errcode": "M_UNKNOWN",
"error": "DNS resolution failure during URL preview generation",
},
)
def test_blacklisted_ip_specific_direct(self):
"""
Blacklisted IP addresses, accessed directly, are not spidered.
"""
channel = self.make_request(
"GET", "preview_url?url=http://192.168.1.1", shorthand=False
)
# No requests made.
self.assertEqual(len(self.reactor.tcpClients), 0)
self.assertEqual(
channel.json_body,
{
"errcode": "M_UNKNOWN",
"error": "IP address blocked by IP blacklist entry",
},
)
self.assertEqual(channel.code, 403)
def test_blacklisted_ip_range_direct(self):
"""
Blacklisted IP ranges, accessed directly, are not spidered.
"""
channel = self.make_request(
"GET", "preview_url?url=http://1.1.1.2", shorthand=False
)
self.assertEqual(channel.code, 403)
self.assertEqual(
channel.json_body,
{
"errcode": "M_UNKNOWN",
"error": "IP address blocked by IP blacklist entry",
},
)
def test_blacklisted_ip_range_whitelisted_ip(self):
"""
Blacklisted but then subsequently whitelisted IP addresses can be
spidered.
"""
self.lookups["example.com"] = [(IPv4Address, "1.1.1.1")]
channel = self.make_request(
"GET",
"preview_url?url=http://example.com",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\nContent-Type: text/html\r\n\r\n"
% (len(self.end_content),)
+ self.end_content
)
self.pump()
self.assertEqual(channel.code, 200)
self.assertEqual(
channel.json_body, {"og:title": "~matrix~", "og:description": "hi"}
)
def test_blacklisted_ip_with_external_ip(self):
"""
If a hostname resolves a blacklisted IP, even if there's a
non-blacklisted one, it will be rejected.
"""
# Hardcode the URL resolving to the IP we want.
self.lookups["example.com"] = [
(IPv4Address, "1.1.1.2"),
(IPv4Address, "10.1.2.3"),
]
channel = self.make_request(
"GET", "preview_url?url=http://example.com", shorthand=False
)
self.assertEqual(channel.code, 502)
self.assertEqual(
channel.json_body,
{
"errcode": "M_UNKNOWN",
"error": "DNS resolution failure during URL preview generation",
},
)
def test_blacklisted_ipv6_specific(self):
"""
Blacklisted IP addresses, found via DNS, are not spidered.
"""
self.lookups["example.com"] = [
(IPv6Address, "3fff:ffff:ffff:ffff:ffff:ffff:ffff:ffff")
]
channel = self.make_request(
"GET", "preview_url?url=http://example.com", shorthand=False
)
# No requests made.
self.assertEqual(len(self.reactor.tcpClients), 0)
self.assertEqual(channel.code, 502)
self.assertEqual(
channel.json_body,
{
"errcode": "M_UNKNOWN",
"error": "DNS resolution failure during URL preview generation",
},
)
def test_blacklisted_ipv6_range(self):
"""
Blacklisted IP ranges, IPs found over DNS, are not spidered.
"""
self.lookups["example.com"] = [(IPv6Address, "2001:800::1")]
channel = self.make_request(
"GET", "preview_url?url=http://example.com", shorthand=False
)
self.assertEqual(channel.code, 502)
self.assertEqual(
channel.json_body,
{
"errcode": "M_UNKNOWN",
"error": "DNS resolution failure during URL preview generation",
},
)
def test_OPTIONS(self):
"""
OPTIONS returns the OPTIONS.
"""
channel = self.make_request(
"OPTIONS", "preview_url?url=http://example.com", shorthand=False
)
self.assertEqual(channel.code, 200)
self.assertEqual(channel.json_body, {})
def test_accept_language_config_option(self):
"""
Accept-Language header is sent to the remote server
"""
self.lookups["example.com"] = [(IPv4Address, "10.1.2.3")]
# Build and make a request to the server
channel = self.make_request(
"GET",
"preview_url?url=http://example.com",
shorthand=False,
await_result=False,
)
self.pump()
# Extract Synapse's tcp client
client = self.reactor.tcpClients[0][2].buildProtocol(None)
# Build a fake remote server to reply with
server = AccumulatingProtocol()
# Connect the two together
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
# Tell Synapse that it has received some data from the remote server
client.dataReceived(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\nContent-Type: text/html\r\n\r\n"
% (len(self.end_content),)
+ self.end_content
)
# Move the reactor along until we get a response on our original channel
self.pump()
self.assertEqual(channel.code, 200)
self.assertEqual(
channel.json_body, {"og:title": "~matrix~", "og:description": "hi"}
)
# Check that the server received the Accept-Language header as part
# of the request from Synapse
self.assertIn(
(
b"Accept-Language: en-UK\r\n"
b"Accept-Language: en-US;q=0.9\r\n"
b"Accept-Language: fr;q=0.8\r\n"
b"Accept-Language: *;q=0.7"
),
server.data,
)
def test_oembed_photo(self):
"""Test an oEmbed endpoint which returns a 'photo' type which redirects the preview to a new URL."""
self.lookups["publish.twitter.com"] = [(IPv4Address, "10.1.2.3")]
self.lookups["cdn.twitter.com"] = [(IPv4Address, "10.1.2.3")]
result = {
"version": "1.0",
"type": "photo",
"url": "http://cdn.twitter.com/matrixdotorg",
}
oembed_content = json.dumps(result).encode("utf-8")
channel = self.make_request(
"GET",
"preview_url?url=http://twitter.com/matrixdotorg/status/12345",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n"
b'Content-Type: application/json; charset="utf8"\r\n\r\n'
)
% (len(oembed_content),)
+ oembed_content
)
self.pump()
# Ensure a second request is made to the photo URL.
client = self.reactor.tcpClients[1][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n"
b"Content-Type: image/png\r\n\r\n"
)
% (len(SMALL_PNG),)
+ SMALL_PNG
)
self.pump()
# Ensure the URL is what was requested.
self.assertIn(b"/matrixdotorg", server.data)
self.assertEqual(channel.code, 200)
body = channel.json_body
self.assertEqual(body["og:url"], "http://twitter.com/matrixdotorg/status/12345")
self.assertTrue(body["og:image"].startswith("mxc://"))
self.assertEqual(body["og:image:height"], 1)
self.assertEqual(body["og:image:width"], 1)
self.assertEqual(body["og:image:type"], "image/png")
def test_oembed_rich(self):
"""Test an oEmbed endpoint which returns HTML content via the 'rich' type."""
self.lookups["publish.twitter.com"] = [(IPv4Address, "10.1.2.3")]
result = {
"version": "1.0",
"type": "rich",
# Note that this provides the author, not the title.
"author_name": "Alice",
"html": "Content Preview
",
}
end_content = json.dumps(result).encode("utf-8")
channel = self.make_request(
"GET",
"preview_url?url=http://twitter.com/matrixdotorg/status/12345",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n"
b'Content-Type: application/json; charset="utf8"\r\n\r\n'
)
% (len(end_content),)
+ end_content
)
self.pump()
self.assertEqual(channel.code, 200)
body = channel.json_body
self.assertEqual(
body,
{
"og:url": "http://twitter.com/matrixdotorg/status/12345",
"og:title": "Alice",
"og:description": "Content Preview",
},
)
def test_oembed_format(self):
"""Test an oEmbed endpoint which requires the format in the URL."""
self.lookups["www.hulu.com"] = [(IPv4Address, "10.1.2.3")]
result = {
"version": "1.0",
"type": "rich",
"html": "Content Preview
",
}
end_content = json.dumps(result).encode("utf-8")
channel = self.make_request(
"GET",
"preview_url?url=http://www.hulu.com/watch/12345",
shorthand=False,
await_result=False,
)
self.pump()
client = self.reactor.tcpClients[0][2].buildProtocol(None)
server = AccumulatingProtocol()
server.makeConnection(FakeTransport(client, self.reactor))
client.makeConnection(FakeTransport(server, self.reactor))
client.dataReceived(
(
b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n"
b'Content-Type: application/json; charset="utf8"\r\n\r\n'
)
% (len(end_content),)
+ end_content
)
self.pump()
# The {format} should have been turned into json.
self.assertIn(b"/api/oembed.json", server.data)
# A URL parameter of format=json should be provided.
self.assertIn(b"format=json", server.data)
self.assertEqual(channel.code, 200)
body = channel.json_body
self.assertEqual(
body,
{
"og:url": "http://www.hulu.com/watch/12345",
"og:description": "Content Preview",
},
)