mirror of
https://github.com/sqlmapproject/sqlmap.git
synced 2026-10-17 05:07:28 +08:00
Miroslav Štampar
548 lines
26 KiB
Python
548 lines
26 KiB
Python
#!/usr/bin/env python
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"""
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Copyright (c) 2006-2026 sqlmap developers (https://sqlmap.org)
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See the file 'LICENSE' for copying permission
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"""
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import base64
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import collections
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import threading
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import json
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import time
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import hashlib
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from lib.core.common import randomStr
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from lib.core.convert import getBytes
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from lib.core.convert import getText
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from lib.core.data import conf
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from lib.core.data import logger
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from lib.core.enums import HTTP_HEADER
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from lib.core.settings import OOB_CORRELATION_ID_LENGTH
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from lib.core.settings import OOB_INTERACTSH_SERVERS
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from lib.core.settings import OOB_NONCE_LENGTH
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# The interactsh client needs RSA-OAEP(SHA-256) + AES-256-CTR. pycryptodome is an
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# optional dependency (sqlmap already uses it opportunistically in lib/utils/hash.py);
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# without it the OOB tier is simply skipped rather than erroring.
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try:
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from Crypto.Cipher import AES
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from Crypto.Cipher import PKCS1_OAEP
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from Crypto.Hash import SHA256
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from Crypto.PublicKey import RSA
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_HAS_CRYPTO = True
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except ImportError:
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_HAS_CRYPTO = False
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def hasCrypto():
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return _HAS_CRYPTO
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class Interactsh(object):
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"""Minimal interactsh client: registers a per-scan RSA key with a public (or
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self-hosted) interactsh server, hands out unique callback URLs, and polls for
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the DNS/HTTP interactions they trigger. Interactions are RSA/AES encrypted on
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the wire and decrypted locally, so the server operator never sees their content.
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All HTTP goes through sqlmap's own request stack (proxy/timeout honoured)."""
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def __init__(self, server=None, token=None):
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self.server = None
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self.token = token or conf.get("oobToken")
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self.correlationId = randomStr(OOB_CORRELATION_ID_LENGTH, lowercase=True)
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self.secret = randomStr(32, lowercase=True)
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self.registered = False
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self._key = None
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self._dnsNonce = None
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self._poller = None
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# Guards the poller create/start decision so two callers racing on an unstarted
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# session cannot each build their own poller and destructively poll one session.
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self._pollerLock = threading.Lock()
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# Set under _pollerLock while stop() tears down: blocks _ensurePoller from restarting the
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# poller in the gap between stop() and close()/deregister().
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self._stopping = False
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if not _HAS_CRYPTO:
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return
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self._key = RSA.generate(2048)
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pubKey = getText(base64.b64encode(getBytes(self._key.publickey().export_key(format="PEM"))))
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candidates = [server] if server else list(OOB_INTERACTSH_SERVERS)
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for candidate in candidates:
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if not candidate:
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continue
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body = json.dumps({"public-key": pubKey, "secret-key": self.secret, "correlation-id": self.correlationId})
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if self._request("https://%s/register" % candidate, post=body):
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self.server = candidate
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self.registered = True
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logger.debug("registered with OOB interaction server '%s'" % candidate)
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break
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def _request(self, url, post=None):
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"""Direct request to the interactsh server (a fixed service, never the target).
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Self-contained on urllib so it works regardless of sqlmap's request-stack init
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order (it is also called during option setup, before getPage is usable); honours
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--proxy and tolerates self-signed certs like the rest of sqlmap. Returns the
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response body text on success, otherwise None."""
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try:
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import ssl
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try:
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from urllib.request import Request as _Request, build_opener, ProxyHandler, HTTPSHandler
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except ImportError:
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from urllib2 import Request as _Request, build_opener, ProxyHandler, HTTPSHandler
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headers = {HTTP_HEADER.CONTENT_TYPE: "application/json"} if post is not None else {HTTP_HEADER.ACCEPT: "application/json"}
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if self.token:
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headers[HTTP_HEADER.AUTHORIZATION] = self.token
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handlers = []
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try:
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# Verify TLS for the (public, valid-cert) interaction server by default;
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# only skip verification when the user has globally opted out (--force-ssl-verify
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# off / verifyCert False), matching sqlmap's own TLS posture.
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context = ssl.create_default_context()
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if conf.get("verifyCert") is False:
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context.check_hostname = False
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context.verify_mode = ssl.CERT_NONE
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handlers.append(HTTPSHandler(context=context))
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except Exception:
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pass
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if conf.get("proxy"):
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handlers.append(ProxyHandler({"http": conf.proxy, "https": conf.proxy}))
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request = _Request(url, data=getBytes(post) if post is not None else None, headers=headers)
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# request_timeout() is the single source of truth for every interactsh network op so
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# InteractshPoller.stop() can join for exactly one /poll network call.
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response = build_opener(*handlers).open(request, timeout=self.request_timeout())
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return getText(response.read())
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except Exception as ex:
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logger.debug("OOB request to '%s' failed: %s" % (url, getText(ex)))
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return None
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def request_timeout(self):
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"""Network timeout (seconds) applied to every /poll and /deregister request. Interactsh
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derives its /poll network timeout identically, so InteractshPoller.stop() can join for
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exactly one of these before the thread is guaranteed to have exited."""
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return conf.get("timeout") or _DEFAULT_NETWORK_TIMEOUT
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def url(self):
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"""Return a fresh unique callback URL (host = correlationId + nonce)."""
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nonce = randomStr(OOB_NONCE_LENGTH, lowercase=True)
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return "http://%s%s.%s" % (self.correlationId, nonce, self.server)
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def dnsDomain(self):
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"""Stable domain suffix (host = correlationId + a fixed nonce) usable as an
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exfiltration suffix - additional labels prepended by a payload still resolve
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to this correlation id, so every DNS lookup under it is captured."""
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if not self._dnsNonce:
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self._dnsNonce = randomStr(OOB_NONCE_LENGTH, lowercase=True)
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return "%s%s.%s" % (self.correlationId, self._dnsNonce, self.server)
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def dnsNames(self):
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"""Return the fully-qualified names (minus the server suffix) of the DNS lookups
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captured so far, e.g. 'prefix.<hex>.suffix.<correlationId><nonce>'.
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This is a *snapshot* over the single background poller's in-memory queue: it ensures the
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poller is running and drains whatever it has already staged, so it does not itself issue
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a fresh /poll. On the very first call after registration the poller may not have finished
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its first round-trip yet and can therefore return [] even though interactions exist -
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retry the call rather than treating that first call as authoritative."""
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return [_.get("full-id")
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for _ in self._consume(
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lambda _: _.get("protocol") == "dns" and _.get("full-id"),
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None)]
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def httpRequests(self):
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"""Return the captured HTTP interactions (collector half of an HTTP-based out-of-band
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data channel). Unlike DNS, where the value rides the queried hostname, an HTTP callback
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carries its payload in the request line/body - so the interaction itself is the evidence.
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interactsh stores each record with a ``raw-request`` (the full dumped request), a
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``protocol`` (``http`` or ``https``) and a ``remote-address`` - it does not pre-parse the
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path/query. A value with no safe-in-URL character set is therefore embedded in a
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query-string *parameter name* (the path stays a constant request line and only the
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attacker-controlled name varies) and the decoded names are returned here.
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"""
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retVal = []
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for _ in self._consume(lambda _: _.get("protocol") in ("http", "https"), None):
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retVal.append(self._renderHttpRequest(_))
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return retVal
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def _renderHttpRequest(self, record):
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interaction = {
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"full-id": record.get("full-id") or "",
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"client": record.get("remote-address") or record.get("client") or "",
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"request": record.get("raw-request") or "",
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"query-param-names": [],
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}
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raw = interaction["request"]
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target = _parseHttpRequestTarget(raw) if raw else (record.get("full-id") or "")
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if target:
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interaction["query-param-names"] = _extractQueryStringNames(target)
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return interaction
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def _ensurePoller(self):
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"""Start the single background /poll consumer (idempotent). The poller is the only code
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that calls the remote endpoint; DNS/HTTP consumers then read the same records from
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memory, so they never drain each other. No-op without crypto, since /poll cannot then be
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decrypted."""
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if not _HAS_CRYPTO:
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return
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# The whole create-or-reuse-and-start sequence is under one lock, so exactly one
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# background poller is ever created and started for this session. A poller must only run
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# for a live, registered session: skip if the session was never registered, and skip if
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# stop() is in progress (so no poller can be restarted between stop() and deregister()).
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with self._pollerLock:
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if not self.registered or self._stopping:
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return
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poller = getattr(self, "_poller", None)
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if poller is None:
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self._poller = poller = InteractshPoller(self)
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if not poller.isRunning():
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poller.start()
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def _consume(self, selector, deadline=None, sync=False):
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"""Return records matching selector.
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For normal registered operation the single background poller drains the remote session
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(zero extra network calls from the consumer, and exactly one caller ever drains it), so
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we ensure it is running and read its in-memory queue. ``sync=True`` forces the direct
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``poll()`` path for the deprecated fallback / explicit testing.
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``deadline`` is an absolute timestamp: ``None`` drains the current queue only (no wait),
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used by snapshot-style callers such as ``httpRequests``/``dnsNames``.
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Outside ``sync=True`` only the background poller ever calls the remote ``poll()`` - the
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invariant this method enforces. A stale poller (never started, or started then stopped by
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``stop()``) yields ``[]`` rather than a second, unsynchronised ``poll()`` that could
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destructively drain the shared session from the wrong caller.
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``sync=True`` forces the direct-poll path, but only for a live, registered session that
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has no background poller already draining it - the poller is the only code that is allowed
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to call the remote endpoint, so a spurious ``sync=True`` during normal operation drains the
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running poller's queue instead of adding a second destructive ``poll()`` caller. Once
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``stop()`` has begun, no caller initiates another remote ``poll()`` - not this
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compatibility path either."""
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if sync:
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with self._pollerLock:
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if self._stopping or not self.registered:
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return []
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poller = getattr(self, "_poller", None)
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if poller is None or not poller.isRunning():
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# Keep the lock across this compatibility poll so _ensurePoller() cannot start
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# a background poller concurrently in the gap between the check and poll()
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# (which would then become a second /poll caller).
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return [record for record in self.poll() if self._safeSelector(selector, record)]
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# Releasing the lock before draining the poller's queue keeps _ensurePoller() free too.
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return poller.drain_matching(selector, deadline)
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self._ensurePoller()
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poller = getattr(self, "_poller", None)
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if poller is not None and poller.isRunning():
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return poller.drain_matching(selector, deadline)
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return []
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def _safeSelector(self, selector, record):
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try:
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return bool(selector(record))
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except Exception as ex:
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logger.debug("interactsh selector error: %s" % getText(ex))
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return False
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def poll(self):
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"""Return the list of decrypted interaction records captured so far."""
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if not self.registered:
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return []
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page = self._request("https://%s/poll?id=%s&secret=%s" % (self.server, self.correlationId, self.secret))
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if not page:
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return []
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try:
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response = json.loads(page)
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except ValueError:
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return []
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retVal = []
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data = response.get("data") or []
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if data:
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try:
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aesKey = PKCS1_OAEP.new(self._key, hashAlgo=SHA256).decrypt(base64.b64decode(response["aes_key"]))
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except Exception as ex:
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logger.debug("OOB AES key decryption failed: %s" % getText(ex))
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return []
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for item in data:
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try:
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raw = base64.b64decode(item)
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plain = AES.new(aesKey, AES.MODE_CTR, nonce=b"", initial_value=raw[:AES.block_size]).decrypt(raw[AES.block_size:])
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retVal.append(json.loads(getText(plain)))
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except Exception as ex:
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logger.debug("OOB interaction decryption failed: %s" % getText(ex))
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return retVal
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def pollUntil(self, attempts, delay):
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"""Poll repeatedly, returning as soon as any interaction is captured."""
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for _ in range(attempts):
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time.sleep(delay)
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interactions = self.poll()
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if interactions:
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return interactions
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return []
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def stop(self):
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"""Stop the background poller (join it) then deregister the interaction.
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The poller is the only code that drains the remote /poll session, so it must be
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stopped before deregistering; stopping it first also prevents it from re-staging
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interactions after close() is called (best-effort on a dead/broken poller).
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Invariant: after stop()/close() returns, this object owns no active polling thread. If the
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poller cannot be stopped within the budget it is deliberately left running (and this
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interaction left registered) so a deregister can never race a still-active /poll drain -
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a later stop()/close() re-runs it and deregisters once the thread has exited."""
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# Set _stopping and capture the poller under _pollerLock (the start/stop race lives under
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# that lock); release the lock before joining so a concurrent _ensurePoller() caller is
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# not blocked for a whole join. The lock prevents a restart of this same poller between here
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# and deregister(); only the (now-dead) poller is joined.
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poller = None
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with self._pollerLock:
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self._stopping = True
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poller = getattr(self, "_poller", None)
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stopped = True
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if poller is not None:
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try:
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stopped = poller.stop()
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except Exception:
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logger.debug("error while stopping interactsh poller")
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stopped = False
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if not stopped:
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# A /poll network call is still draining the session; skip deregister this time and let
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# the next stop()/close() deregister once the thread has actually exited.
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return
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self._deregister()
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def close(self):
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"""Canonical complete teardown: stop the poller AND deregister.
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close() predates the background-poller addition, so every existing/future caller can
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keep using it without learning about stop(); making it do the full shutdown means the
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invariant holds regardless of which entry point is taken: after close() returns this
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object owns no active polling thread."""
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self.stop()
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def _deregister(self):
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if self.registered:
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body = json.dumps({"correlation-id": self.correlationId, "secret-key": self.secret})
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self._request("https://%s/deregister" % self.server, post=body)
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self.registered = False
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# Delay between two remote /poll round-trips in the background poller.
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_POP_POLL_DELAY = 1.0
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# Network timeout (seconds) applied to each interactsh /poll and /deregister request (see
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# Interactsh._request). InteractshPoller.stop() joins for one of these (with a little slack) so a
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# /poll wedged at the remote endpoint cannot keep a dead poller's thread alive past stop().
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_DEFAULT_NETWORK_TIMEOUT = 30
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def _parseHttpRequestTarget(raw_request):
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"""Return the request target (undecoded) from the first line of a raw HTTP request.
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It is deliberately left raw: decoding before splitting on '&'/'=' would corrupt encoded
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delimiters (a value with an unsafe-in-URL character set may hit the same host as its own
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name, e.g. ``?aa%26bb=1`` must parse to one name ``aa&bb``, not two). Downstream code decodes
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each name individually.
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"""
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if not raw_request:
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return ""
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first_line = raw_request.splitlines()[0]
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parts = first_line.split(None, 2)
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if len(parts) >= 2:
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target = parts[1]
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else:
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target = first_line
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return target
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def _unquote(value):
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try:
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from urllib import unquote
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except ImportError:
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from urllib.parse import unquote
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return unquote(value)
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def _extractQueryStringNames(raw_target):
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"""Return the ordered, de-duplicated query-string parameter names from a raw (undecoded) target.
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Split the raw target on literal '&' and the first raw '=', then percent-decode only each
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parameter name individually so encoded delimiters (``%26`` '&', ``%3D`` '=', ``%25`` '%') are
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preserved in the decoded name rather than misinterpreted as structure.
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"""
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try:
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query = raw_target.split("?", 1)[1]
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except IndexError:
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return []
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names = []
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for pair in query.split("&"):
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if not pair:
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continue
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encoded_name = pair.split("=", 1)[0]
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name = _unquote(encoded_name)
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if name and name not in names:
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names.append(name)
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return names
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class InteractshPoller(object):
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"""A single background consumer of one interactsh session: one thread polls /poll and queues
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complete interaction records under a Condition, so the DNS and HTTP consumers read the same
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records from memory without ever calling the remote endpoint twice or draining each other."""
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def __init__(self, client):
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self._client = client
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self._queue = collections.deque()
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self._lock = threading.RLock()
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self._cond = threading.Condition(self._lock)
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self._seen = set()
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self._running = False
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self._thread = None
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def start(self):
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"""Start the poller (idempotent)."""
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with self._lock:
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if self._running:
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return
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self._running = True
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self._thread = threading.Thread(target=self._loop)
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self._thread.daemon = True
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self._thread.start()
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def stop(self):
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"""Stop the poller and join the thread until it actually exits.
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Returns True if the poll thread has exited, False if it could not be stopped within the
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budget (its in-flight /poll request is still running). stop() flips _running and wakes the
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loop, so the thread exits after its current /poll returns - join therefore only has to
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outlast one /poll network operation, whose timeout is derived from the client's request
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timeout. Joining is retried on every call, so a second stop() after a failed first still
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joins the (now-sleeping-loop) thread instead of bailing out before _running was read.
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Only a genuinely hung /poll network call exceeds the budget; the common case exits the
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instant the loop wakes. This is why the stated invariant holds strictly - it is retried,
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not capped at a guessed timeout."""
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with self._lock:
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self._running = False
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self._cond.notify_all()
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thread = self._thread
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if not thread or not thread.is_alive():
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return True
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# stop() has already woken the loop, so the thread exits after its current /poll returns.
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# One join that outlasts one /poll network call is enough; the slack covers the loop's own
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# work before it re-checks _running. A hung request is guarded by retrying stop().
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fn = getattr(self._client, "request_timeout", None)
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network_timeout = fn() if callable(fn) else _DEFAULT_NETWORK_TIMEOUT
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thread.join(network_timeout + _POP_POLL_DELAY)
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return not thread.is_alive()
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|
def isRunning(self):
|
|
return self._running and self._thread is not None and self._thread.is_alive()
|
|
|
|
def _loop(self):
|
|
while self._running:
|
|
try:
|
|
records = self._client.poll()
|
|
with self._cond:
|
|
# Recheck _running after poll() returns: stop() may have set it False while the
|
|
# network call was in flight. Drop the just-received records without staging
|
|
# them, so a stopped poller can never repopulate its queue after shutdown.
|
|
if not self._running:
|
|
break
|
|
for record in records:
|
|
# Only queue interaction protocols sqlmap consumes (dns/http/https). Other
|
|
# interaction types (smtp/ldap/...) would never be drained by sqlmap's
|
|
# consumers and would otherwise accumulate in _queue for the whole session;
|
|
# bounding the queue to what we actually use keeps it from growing.
|
|
if record.get("protocol") not in ("dns", "http", "https"):
|
|
continue
|
|
# Fingerprint the *interaction*, not the payload host ("full-id").
|
|
# protocol + full-id + unique-id only identify the receiving subdomain
|
|
# (a single host drives many interactions); timestamp is a separate, per-
|
|
# interaction field that keeps two identical requests to that host distinct.
|
|
# Per-record try: a malformed interaction (a non-string field making the
|
|
# join raise, or a bytes value getBytes() cannot decode) throws here. Keeping
|
|
# it inside the per-record handler means one odd interaction skips itself
|
|
# without aborting every later interaction in the already-drained batch, which
|
|
# the outer batch-level except would otherwise do.
|
|
try:
|
|
rid_str = "|".join((record.get("protocol") or "",
|
|
record.get("full-id") or "",
|
|
record.get("unique-id") or "",
|
|
record.get("timestamp") or "",
|
|
record.get("raw-request") or "",
|
|
record.get("remote-address") or ""))
|
|
# Hash before storing so _seen never retains a full raw-request (bounded
|
|
# to a fixed-length hexdigest); the review noted raw-request retention
|
|
# grew _seen for the whole session. Hashlib is only consulted when we
|
|
# have a record to fingerprint.
|
|
rid = hashlib.sha256(getBytes(rid_str)).hexdigest()
|
|
except Exception as ex:
|
|
logger.debug("interactsh fingerprint error: %s" % getText(ex))
|
|
continue
|
|
if rid in self._seen:
|
|
continue
|
|
self._seen.add(rid)
|
|
self._queue.append(record)
|
|
self._cond.notify_all()
|
|
except Exception as ex:
|
|
logger.debug("interactsh poller poll error: %s" % getText(ex))
|
|
if self._running:
|
|
time.sleep(_POP_POLL_DELAY)
|
|
|
|
def _safeSelector(self, selector, record):
|
|
try:
|
|
return bool(selector(record))
|
|
except Exception as ex:
|
|
logger.debug("interactsh selector error: %s" % getText(ex))
|
|
return False
|
|
|
|
def drain_matching(self, selector, deadline=None):
|
|
"""Return all currently-queued records matching selector (removing them).
|
|
|
|
``deadline=None`` drains the current queue with no wait (snapshot-style callers such as
|
|
``httpRequests``/``dnsNames``); only ``InteractshDNSServer.pop`` passes an absolute
|
|
deadline to wait for new arrivals. The wait and the scan share one condition critical
|
|
section so a producer cannot enqueue+notify between releasing and reacquiring the lock,
|
|
which would otherwise stall another 0.5 s even when a match already exists."""
|
|
while True:
|
|
with self._cond:
|
|
matched = [record for record in self._queue if self._safeSelector(selector, record)]
|
|
if matched:
|
|
for record in matched:
|
|
self._queue.remove(record)
|
|
return matched
|
|
# Check _running before the first wait as well: stop() may have fired between the
|
|
# scan and a wait() call, so the matching notification has already happened - a bare
|
|
# wait() would otherwise sleep the whole budget for nothing.
|
|
if not self._running:
|
|
return []
|
|
if deadline is None:
|
|
return []
|
|
remaining = deadline - time.time()
|
|
if remaining <= 0:
|
|
return []
|
|
self._cond.wait(timeout=remaining)
|
|
# Wake-up was not for a match; if stop() fired in the meantime no producer can
|
|
# ever enqueue one, so exit promptly instead of looping for the full deadline.
|
|
if not self._running:
|
|
return []
|