Switch to intermediate Mozilla cert profile (#15957)

* Allow choosing intermediate SSL profile

* Fix tests

homeassistant/components/http/__init__.py

@@ -49,6 +49,10 @@
 CONF_TRUSTED_NETWORKS = 'trusted_networks'
 CONF_LOGIN_ATTEMPTS_THRESHOLD = 'login_attempts_threshold'
 CONF_IP_BAN_ENABLED = 'ip_ban_enabled'
+CONF_SSL_PROFILE = 'ssl_profile'
+
+SSL_MODERN = 'modern'
+SSL_INTERMEDIATE = 'intermediate'
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -74,7 +78,9 @@
     vol.Optional(CONF_LOGIN_ATTEMPTS_THRESHOLD,
                  default=NO_LOGIN_ATTEMPT_THRESHOLD):
         vol.Any(cv.positive_int, NO_LOGIN_ATTEMPT_THRESHOLD),
-    vol.Optional(CONF_IP_BAN_ENABLED, default=True): cv.boolean
+    vol.Optional(CONF_IP_BAN_ENABLED, default=True): cv.boolean,
+    vol.Optional(CONF_SSL_PROFILE, default=SSL_MODERN):
+        vol.In([SSL_INTERMEDIATE, SSL_MODERN]),
 })
 
 CONFIG_SCHEMA = vol.Schema({
@@ -123,6 +129,7 @@ async def async_setup(hass, config):
     trusted_networks = conf[CONF_TRUSTED_NETWORKS]
     is_ban_enabled = conf[CONF_IP_BAN_ENABLED]
     login_threshold = conf[CONF_LOGIN_ATTEMPTS_THRESHOLD]
+    ssl_profile = conf[CONF_SSL_PROFILE]
 
     if api_password is not None:
         logging.getLogger('aiohttp.access').addFilter(
@@ -141,7 +148,8 @@ async def async_setup(hass, config):
         trusted_proxies=trusted_proxies,
         trusted_networks=trusted_networks,
         login_threshold=login_threshold,
-        is_ban_enabled=is_ban_enabled
+        is_ban_enabled=is_ban_enabled,
+        ssl_profile=ssl_profile,
     )
 
     async def stop_server(event):
@@ -181,7 +189,7 @@ def __init__(self, hass, api_password,
                  ssl_certificate, ssl_peer_certificate,
                  ssl_key, server_host, server_port, cors_origins,
                  use_x_forwarded_for, trusted_proxies, trusted_networks,
-                 login_threshold, is_ban_enabled):
+                 login_threshold, is_ban_enabled, ssl_profile):
         """Initialize the HTTP Home Assistant server."""
         app = self.app = web.Application(
             middlewares=[staticresource_middleware])
@@ -222,6 +230,7 @@ def __init__(self, hass, api_password,
         self.server_port = server_port
         self.trusted_networks = trusted_networks
         self.is_ban_enabled = is_ban_enabled
+        self.ssl_profile = ssl_profile
         self._handler = None
         self.server = None
 
@@ -308,7 +317,10 @@ async def start(self):
 
         if self.ssl_certificate:
             try:
-                context = ssl_util.server_context()
+                if self.ssl_profile == SSL_INTERMEDIATE:
+                    context = ssl_util.server_context_intermediate()
+                else:
+                    context = ssl_util.server_context_modern()
                 context.load_cert_chain(self.ssl_certificate, self.ssl_key)
             except OSError as error:
                 _LOGGER.error("Could not read SSL certificate from %s: %s",

homeassistant/util/ssl.py

@@ -13,7 +13,7 @@ def client_context() -> ssl.SSLContext:
     return context
 
 
-def server_context() -> ssl.SSLContext:
+def server_context_modern() -> ssl.SSLContext:
     """Return an SSL context following the Mozilla recommendations.
 
     TLS configuration follows the best-practice guidelines specified here:
@@ -37,4 +37,58 @@ def server_context() -> ssl.SSLContext:
         "ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:"
         "ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256"
     )
+
+    return context
+
+
+def server_context_intermediate() -> ssl.SSLContext:
+    """Return an SSL context following the Mozilla recommendations.
+
+    TLS configuration follows the best-practice guidelines specified here:
+    https://wiki.mozilla.org/Security/Server_Side_TLS
+    Intermediate guidelines are followed.
+    """
+    context = ssl.SSLContext(ssl.PROTOCOL_TLS)  # pylint: disable=no-member
+
+    context.options |= (
+        ssl.OP_NO_SSLv2 | ssl.OP_NO_SSLv3 |
+        ssl.OP_CIPHER_SERVER_PREFERENCE
+    )
+    if hasattr(ssl, 'OP_NO_COMPRESSION'):
+        context.options |= ssl.OP_NO_COMPRESSION
+
+    context.set_ciphers(
+        "ECDHE-ECDSA-CHACHA20-POLY1305:"
+        "ECDHE-RSA-CHACHA20-POLY1305:"
+        "ECDHE-ECDSA-AES128-GCM-SHA256:"
+        "ECDHE-RSA-AES128-GCM-SHA256:"
+        "ECDHE-ECDSA-AES256-GCM-SHA384:"
+        "ECDHE-RSA-AES256-GCM-SHA384:"
+        "DHE-RSA-AES128-GCM-SHA256:"
+        "DHE-RSA-AES256-GCM-SHA384:"
+        "ECDHE-ECDSA-AES128-SHA256:"
+        "ECDHE-RSA-AES128-SHA256:"
+        "ECDHE-ECDSA-AES128-SHA:"
+        "ECDHE-RSA-AES256-SHA384:"
+        "ECDHE-RSA-AES128-SHA:"
+        "ECDHE-ECDSA-AES256-SHA384:"
+        "ECDHE-ECDSA-AES256-SHA:"
+        "ECDHE-RSA-AES256-SHA:"
+        "DHE-RSA-AES128-SHA256:"
+        "DHE-RSA-AES128-SHA:"
+        "DHE-RSA-AES256-SHA256:"
+        "DHE-RSA-AES256-SHA:"
+        "ECDHE-ECDSA-DES-CBC3-SHA:"
+        "ECDHE-RSA-DES-CBC3-SHA:"
+        "EDH-RSA-DES-CBC3-SHA:"
+        "AES128-GCM-SHA256:"
+        "AES256-GCM-SHA384:"
+        "AES128-SHA256:"
+        "AES256-SHA256:"
+        "AES128-SHA:"
+        "AES256-SHA:"
+        "DES-CBC3-SHA:"
+        "!DSS"
+    )
+
     return context

tests/components/http/test_init.py

@@ -1,10 +1,13 @@
 """The tests for the Home Assistant HTTP component."""
 import logging
 import unittest
+from unittest.mock import patch
 
 from homeassistant.setup import async_setup_component
 
 import homeassistant.components.http as http
+from homeassistant.util.ssl import (
+    server_context_modern, server_context_intermediate)
 
 
 class TestView(http.HomeAssistantView):
@@ -169,3 +172,56 @@ async def test_proxy_config_only_trust_proxies(hass):
             http.CONF_TRUSTED_PROXIES: ['127.0.0.1']
         }
     }) is not True
+
+
+async def test_ssl_profile_defaults_modern(hass):
+    """Test default ssl profile."""
+    assert await async_setup_component(hass, 'http', {}) is True
+
+    hass.http.ssl_certificate = 'bla'
+
+    with patch('ssl.SSLContext.load_cert_chain'), \
+        patch('homeassistant.util.ssl.server_context_modern',
+              side_effect=server_context_modern) as mock_context:
+        await hass.async_start()
+        await hass.async_block_till_done()
+
+    assert len(mock_context.mock_calls) == 1
+
+
+async def test_ssl_profile_change_intermediate(hass):
+    """Test setting ssl profile to intermediate."""
+    assert await async_setup_component(hass, 'http', {
+        'http': {
+            'ssl_profile': 'intermediate'
+        }
+    }) is True
+
+    hass.http.ssl_certificate = 'bla'
+
+    with patch('ssl.SSLContext.load_cert_chain'), \
+        patch('homeassistant.util.ssl.server_context_intermediate',
+              side_effect=server_context_intermediate) as mock_context:
+        await hass.async_start()
+        await hass.async_block_till_done()
+
+    assert len(mock_context.mock_calls) == 1
+
+
+async def test_ssl_profile_change_modern(hass):
+    """Test setting ssl profile to modern."""
+    assert await async_setup_component(hass, 'http', {
+        'http': {
+            'ssl_profile': 'modern'
+        }
+    }) is True
+
+    hass.http.ssl_certificate = 'bla'
+
+    with patch('ssl.SSLContext.load_cert_chain'), \
+        patch('homeassistant.util.ssl.server_context_modern',
+              side_effect=server_context_modern) as mock_context:
+        await hass.async_start()
+        await hass.async_block_till_done()
+
+    assert len(mock_context.mock_calls) == 1

tests/scripts/test_check_config.py

@@ -159,7 +159,9 @@ def test_secrets(self, isfile_patch):
                 'login_attempts_threshold': -1,
                 'server_host': '0.0.0.0',
                 'server_port': 8123,
-                'trusted_networks': []}
+                'trusted_networks': [],
+                'ssl_profile': 'modern',
+            }
             assert res['secret_cache'] == {secrets_path: {'http_pw': 'abc123'}}
             assert res['secrets'] == {'http_pw': 'abc123'}
             assert normalize_yaml_files(res) == [