From e17d5a6a47c1405a799a06754d3e905856e3035d Mon Sep 17 00:00:00 2001
From: florian <264356+flozilla@users.noreply.github.com>
Date: Tue, 11 Jul 2023 21:31:27 +0200
Subject: [PATCH 10/10] CVE-2023-38200

Extend Registrar SSL socket to be non-blocking

Fixes: CVE-2023-38200

Upstream:
 - https://github.com/keylime/keylime/commit/c68d8f0b7
 - https://github.com/keylime/keylime/commit/27d515f4b
---
 keylime/registrar_common.py | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/keylime/registrar_common.py b/keylime/registrar_common.py
index d1d20dd..6441e3b 100644
--- a/keylime/registrar_common.py
+++ b/keylime/registrar_common.py
@@ -2,8 +2,10 @@ import base64
 import http.server
 import ipaddress
 import os
+import select
 import signal
 import socket
+import ssl
 import sys
 import threading
 from http.server import BaseHTTPRequestHandler, HTTPServer
@@ -77,6 +79,25 @@ class BaseHandler(BaseHTTPRequestHandler, SessionManager):
 
 
 class ProtectedHandler(BaseHandler):
+    def handle(self) -> None:
+        """Need to perform SSL handshake here, as
+        do_handshake_on_connect=False for non-blocking SSL socket"""
+        while True:
+            try:
+                self.request.do_handshake()
+                break
+            except ssl.SSLWantReadError:
+                select.select([self.request], [], [])
+            except ssl.SSLWantWriteError:
+                select.select([], [self.request], [])
+            except ssl.SSLError as e:
+                logger.error("SSL connection error: %s", e)
+                return
+            except Exception as e:
+                logger.error("General communication failure: %s", e)
+                return
+        BaseHTTPRequestHandler.handle(self)
+
     def do_HEAD(self) -> None:
         """HEAD not supported"""
         web_util.echo_json_response(self, 405, "HEAD not supported")
@@ -494,7 +515,7 @@ def start(host: str, tlsport: int, port: int) -> None:
     protected_server = RegistrarServer((host, tlsport), ProtectedHandler)
     context = web_util.init_mtls("registrar", logger=logger)
     if context is not None:
-        protected_server.socket = context.wrap_socket(protected_server.socket, server_side=True)
+        protected_server.socket = context.wrap_socket(protected_server.socket, server_side=True, do_handshake_on_connect=False)
     thread_protected_server = threading.Thread(target=protected_server.serve_forever)
 
     # Set up the unprotected registrar server
-- 
2.41.0