Add support for custom HTTP user agent

sslyze/connection_helpers/http_request_generator.py

@@ -1,3 +1,5 @@
+from typing import Optional
+
 from sslyze import __version__
 
 
@@ -16,5 +18,7 @@ class HttpRequestGenerator:
     )
 
     @classmethod
-    def get_request(cls, host: str, path: str = "/") -> bytes:
-        return cls.HTTP_GET_FORMAT.format(host=host, path=path, user_agent=cls.DEFAULT_USER_AGENT).encode("utf-8")
+    def get_request(cls, host: str, path: str = "/", user_agent: Optional[str] = None) -> bytes:
+        if not user_agent:
+            user_agent = cls.DEFAULT_USER_AGENT
+        return cls.HTTP_GET_FORMAT.format(host=host, path=path, user_agent=user_agent).encode("utf-8")

sslyze/plugins/early_data_plugin.py

@@ -89,7 +89,10 @@ def _test_early_data_support(server_info: ServerConnectivityInfo) -> bool:
         # Perform an SSL handshake and keep the session
         ssl_connection.connect()
         # Send and receive data for the TLS session to be created
-        ssl_connection.ssl_client.write(HttpRequestGenerator.get_request(host=server_info.server_location.hostname))
+        ssl_connection.ssl_client.write(HttpRequestGenerator.get_request(
+            host=server_info.server_location.hostname,
+            user_agent=server_info.network_configuration.http_user_agent
+        ))
         ssl_connection.ssl_client.read(2048)
         session = ssl_connection.ssl_client.get_session()
     except ServerRejectedTlsHandshake:

sslyze/plugins/http_headers_plugin.py

@@ -200,7 +200,9 @@ def _retrieve_and_analyze_http_response(server_info: ServerConnectivityInfo) ->
             # Send an HTTP GET request to the server
             ssl_connection.ssl_client.write(
                 HttpRequestGenerator.get_request(
-                    host=server_info.network_configuration.tls_server_name_indication, path=next_location_path
+                    host=server_info.network_configuration.tls_server_name_indication,
+                    path=next_location_path,
+                    user_agent=server_info.network_configuration.http_user_agent,
                 )
             )
             http_response = HttpResponseParser.parse_from_ssl_connection(ssl_connection.ssl_client)
@@ -225,7 +227,9 @@ def _retrieve_and_analyze_http_response(server_info: ServerConnectivityInfo) ->
 
     # Prepare the results
     initial_http_request = HttpRequestGenerator.get_request(
-        host=server_info.network_configuration.tls_server_name_indication, path="/"
+        host=server_info.network_configuration.tls_server_name_indication,
+        path="/",
+        user_agent=server_info.network_configuration.http_user_agent,
     ).decode("ascii")
 
     if http_error_trace:

sslyze/server_setting.py

@@ -11,6 +11,7 @@
 
 from nassl.ssl_client import OpenSslFileTypeEnum, SslClient
 
+from sslyze import __version__
 from sslyze.connection_helpers.opportunistic_tls_helpers import ProtocolWithOpportunisticTlsEnum
 from sslyze.errors import InvalidServerNetworkConfigurationError, ServerHostnameCouldNotBeResolved
 
@@ -173,6 +174,8 @@ class ServerNetworkConfiguration:
         xmpp_to_hostname: The hostname to set within the `to` attribute of the XMPP stream. If not supplied, the
             server's hostname will be used. Should only be set if the supplied `tls_wrapped_protocol` is an
             XMPP protocol.
+        http_user_agent: The User-Agent to send in HTTP requests. If not supplied, a default Chrome-like
+            is used that includes the sslyze version.
         network_timeout: The timeout (in seconds) to be used when attempting to establish a connection to the
             server.
         network_max_retries: The number of retries SSLyze will perform when attempting to establish a connection
@@ -184,6 +187,7 @@ class ServerNetworkConfiguration:
     tls_client_auth_credentials: Optional[ClientAuthenticationCredentials] = None
 
     xmpp_to_hostname: Optional[str] = None
+    http_user_agent: Optional[str] = None
 
     network_timeout: int = 5
     network_max_retries: int = 3