citrixpot/test_profile.py

"""Run: python3 test_profile.py. Passive fingerprints and inert header/body intake."""
import gzip
import base64
import hashlib
import http.client
import struct
import threading
import xml.etree.ElementTree as ET
import urllib.parse
import zlib

from honeypot import ASSET_MTIME, Engine, Server
from test_private_boundary import PATHS

events = []
server = Server(('127.0.0.1', 0), Engine(lambda event, **data: events.append(dict(event=event, **data))))
server.serve_guest_files = False
thread = threading.Thread(target=server.serve_forever, daemon=True)
thread.start()

def request(path, method='GET', body=None, headers=None):
    c = http.client.HTTPConnection('127.0.0.1', server.server_port, timeout=3)
    c.request(method, path, body, headers or {})
    r = c.getresponse()
    result = r.status, dict(r.getheaders()), r.read()
    c.close()
    return result

try:
    status, headers, html = request('/')
    assert status == 200 and b'<title class="_ctxstxt_NetscalerGateway">Citrix Gateway</title>' in html
    assert headers['Set-Cookie'].startswith('NSC_')  # WhatWeb passive matcher
    for suffix in ('lang', 'lang-ext'):
        path = '/vpn/js/rdx/core/' + suffix + '/rdx_en.json'
        status, headers, compressed = request(path + '.gz')
        assert status == 200 and headers['Content-Encoding'] == 'gzip'
        assert compressed.startswith(b'\x1f\x8b\x08\x08') and b'rdx_en.json\x00' in compressed[:100]
        assert struct.unpack('<I', compressed[4:8])[0] == ASSET_MTIME == 1723114781
        assert gzip.decompress(compressed) == request(path)[2]
        assert request(path + '.gz', 'HEAD')[2] == b''
    status, headers, xml = request('/nf/auth/getAuthenticationRequirements.do')
    root = ET.fromstring(xml)
    ns = {'c': 'http://citrix.com/authentication/response/1'}
    assert root.find('c:AuthenticationRequirements/c:PostBack', ns).text == '/nf/auth/doAuthentication.do'
    assert len(root.findall('.//c:Requirement', ns)) == 3
    # Inert markers, no exploit syntax or commands. Original intake still correlated.
    status, _, _ = request('/unknown', 'POST', b'base64=inert-marker',
                           {'Content-Type': 'application/x-www-form-urlencoded', 'X_Test': 'NSPPE inert-marker'})
    assert status == 404
    indicator = next(e for e in events if e['event'] == 'request_indicators')
    assert {'source': 'header:X_Test', 'kind': 'netscaler-log-marker'} in indicator['indicators']
    assert {'source': 'body', 'kind': 'encoded-content'} in indicator['indicators']
    assert any(e['event'] == 'request_body' and e['request_id'] == indicator['request_id'] for e in events)
    xml = b'<Response xmlns="urn:oasis:names:tc:SAML:2.0:protocol">inert-marker</Response>'
    form = urllib.parse.urlencode({'SAMLResponse': base64.b64encode(xml).decode()}).encode()
    assert request('/cgi/samlauth', 'POST', form, {'Content-Type': 'application/x-www-form-urlencoded'})[0] == 404
    saml = next(e for e in reversed(events) if e['event'] == 'saml_payload')
    assert saml['source'] == 'form' and saml['evidence']['sha256'] == hashlib.sha256(xml).hexdigest()
    raw_body = next(e for e in events if e['event'] == 'request_body' and e['request_id'] == saml['request_id'])
    assert raw_body['evidence']['sha256'] == hashlib.sha256(form).hexdigest()
    def redirect(value):
        compressor = zlib.compressobj(wbits=-zlib.MAX_WBITS)
        compressed = compressor.compress(value) + compressor.flush()
        return '/cgi/samlauth?' + urllib.parse.urlencode({'SAMLRequest': base64.b64encode(compressed).decode()})
    assert request(redirect(xml))[0] == 404
    assert any(e['event'] == 'saml_payload' and e['encoding'] == 'base64+deflate'
               and e['evidence']['sha256'] == hashlib.sha256(xml).hexdigest() for e in events)
    before = len(events)
    assert request(redirect(b'A' * 65537))[0] == 404
    assert any(e['event'] == 'limit' and e.get('resource') == 'saml_inflation' for e in events[before:])
    assert not any(e['event'] == 'saml_payload' and e['encoding'] == 'base64+deflate' for e in events[before:])
    assert request('/cgi/samlauth?SAMLResponse=not-base64')[0] == 404
    assert any(e['event'] == 'saml_decode_error' for e in events)
    assert request('/logon/LogonPoint/Authentication/GetUserName')[0] == 404
    assert any({'source': 'uri', 'kind': 'gateway-username-probe'} in e.get('indicators', []) for e in events)
    for path in PATHS + ('/.env', '/nsconfig/ns.conf', '/api/events'):
        status, _, body = request(path)
        assert status == 404 and body == b'Not Found', path
    print('PASS: Gateway fingerprint, gzip metadata, auth XML, SAML bytes/inflation bounds, indicators, private boundary')
finally:
    server.shutdown()
    server.server_close()
    thread.join(3)