docker proxy demo

server.py

from http.server import BaseHTTPRequestHandler, HTTPServer
import ssl
import base64

# Test of the docker login authentication mechanism for building an authentication proxy.
# NB: you may want to remove the SSL configuration below or generate certificate using:
# openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout ./server.key -out ./server.crt
#
# USAGE:
# python server.py
# docker login localhost:5678 -p your-password -u your-user
#
# docker login will in order:
# - try to skip the login step (it does not send auth data)
# - if it receives a 401, it will send a second request with auth data
class RequestHandler(BaseHTTPRequestHandler):
    def authenticate(self):
        # Extract the Authorization header if present
        auth_header = self.headers.get('Authorization')
        if auth_header and auth_header.startswith('Basic '):
            # Decode the Base64-encoded credentials
            encoded_credentials = auth_header.split(' ')[1]
            decoded_credentials = base64.b64decode(encoded_credentials).decode('utf-8')
            username, password = decoded_credentials.split(':')
            # Print the extracted username and password
            print(f"Username: {username}")
            print(f"Password: {password}")
            return True
        return False

    def do_GET(self):
        # Handle GET requests
        if self.path == '/v2/':
            # If the request is to the /v2/ endpoint, attempt authentication
            if self.authenticate():
                self.send_response(200)
                self.end_headers()
                self.wfile.write(b'GET request received')
            else:
                # If no or invalid credentials, respond with 401 Unauthorized and request authentication
                self.send_response(401)
                self.send_header('WWW-Authenticate', 'Basic realm="Docker Registry"')
                self.end_headers()
                self.wfile.write(b'Authentication required')
        else:
            # If the request is to any other endpoint, respond with 404 Not Found
            self.send_response(404)
            self.end_headers()
            self.wfile.write(b'Not Found')

def run(server_class=HTTPServer, handler_class=RequestHandler, port=9888):
    server_address = ('', port)
    httpd = server_class(server_address, handler_class)

    # Create an SSL context, this is not required since docker will fallback to http.
    context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
    context.load_cert_chain(certfile='./server.crt', keyfile='./server.key')

    # Wrap the server's socket with the SSL context to enable HTTPS
    httpd.socket = context.wrap_socket(httpd.socket, server_side=True)

    print(f'Starting https server on port {port}')
    httpd.serve_forever()

if __name__ == '__main__':
    run()