import logging import requests from flask import url_for from urlparse import urljoin from data.database import CloseForLongOperation from data import model from data.model.storage import get_storage_locations from util.secscan.validator import SecurityConfigValidator from util.security.instancekeys import InstanceKeys from util.security.registry_jwt import generate_bearer_token, build_context_and_subject from util import get_app_url TOKEN_VALIDITY_LIFETIME_S = 60 # Amount of time the security scanner has to call the layer URL UNKNOWN_PARENT_LAYER_ERROR_MSG = 'worker: parent layer is unknown, it must be processed first' logger = logging.getLogger(__name__) class AnalyzeLayerException(Exception): """ Exception raised when a layer fails to analyze due to a request issue. """ class AnalyzeLayerRetryException(Exception): """ Exception raised when a layer fails to analyze due to a request issue, and the request should be retried. """ class MissingParentLayerException(AnalyzeLayerException): """ Exception raised when the parent of the layer is missing from the security scanner. """ class InvalidLayerException(AnalyzeLayerException): """ Exception raised when the layer itself cannot be handled by the security scanner. """ class APIRequestFailure(Exception): """ Exception raised when there is a failure to conduct an API request. """ _API_METHOD_INSERT = 'layers' _API_METHOD_GET_LAYER = 'layers/%s' _API_METHOD_MARK_NOTIFICATION_READ = 'notifications/%s' _API_METHOD_GET_NOTIFICATION = 'notifications/%s' _API_METHOD_PING = 'metrics' class SecurityScannerAPI(object): """ Helper class for talking to the Security Scan service (Clair). """ def __init__(self, app, config, storage, client=None, skip_validation=False): if not skip_validation: config_validator = SecurityConfigValidator(config) if not config_validator.valid(): logger.warning('Invalid config provided to SecurityScannerAPI') return self._app = app self._config = config self._instance_keys = InstanceKeys(app) self._client = client or config['HTTPCLIENT'] self._storage = storage self._default_storage_locations = config['DISTRIBUTED_STORAGE_PREFERENCE'] self._target_version = config.get('SECURITY_SCANNER_ENGINE_VERSION_TARGET', 2) def _get_image_url_and_auth(self, image): """ Returns a tuple of the url and the auth header value that must be used to fetch the layer data itself. If the image can't be addressed, we return None. """ path = model.storage.get_layer_path(image.storage) locations = self._default_storage_locations if not self._storage.exists(locations, path): locations = get_storage_locations(image.storage.uuid) if not locations or not self._storage.exists(locations, path): logger.warning('Could not find a valid location to download layer %s.%s out of %s', image.docker_image_id, image.storage.uuid, locations) return None, None uri = self._storage.get_direct_download_url(locations, path) auth_header = None if uri is None: # Use the registry API instead, with a signed JWT giving access repo_name = image.repository.name namespace_name = image.repository.namespace_user.username repository_and_namespace = '/'.join([namespace_name, repo_name]) # Generate the JWT which will authorize this audience = self._app.config['SERVER_HOSTNAME'] context, subject = build_context_and_subject(None, None, None) access = [{ 'type': 'repository', 'name': repository_and_namespace, 'actions': ['pull'], }] auth_token = generate_bearer_token(audience, subject, context, access, TOKEN_VALIDITY_LIFETIME_S, self._instance_keys) auth_header = 'Bearer ' + auth_token with self._app.test_request_context('/'): relative_layer_url = url_for('v2.download_blob', repository=repository_and_namespace, digest=image.storage.content_checksum) uri = urljoin(get_app_url(self._config), relative_layer_url) return uri, auth_header def _new_analyze_request(self, image): """ Create the request body to submit the given image for analysis. If the image's URL cannot be found, returns None. """ url, auth_header = self._get_image_url_and_auth(image) if url is None: return None layer_request = { 'Name': '%s.%s' % (image.docker_image_id, image.storage.uuid), 'Path': url, 'Format': 'Docker', } if auth_header is not None: layer_request['Headers'] = { 'Authorization': auth_header, } if image.parent.docker_image_id and image.parent.storage.uuid: layer_request['ParentName'] = '%s.%s' % (image.parent.docker_image_id, image.parent.storage.uuid) return { 'Layer': layer_request, } def ping(self): """ Calls GET on the metrics endpoint of the security scanner to ensure it is running and properly configured. Returns the HTTP response. """ try: return self._call('GET', _API_METHOD_PING) except requests.exceptions.Timeout: logger.exception('Timeout when trying to connect to security scanner endpoint') raise Exception('Timeout when trying to connect to security scanner endpoint') except requests.exceptions.ConnectionError: logger.exception('Connection error when trying to connect to security scanner endpoint') raise Exception('Connection error when trying to connect to security scanner endpoint') except (requests.exceptions.RequestException, ValueError): logger.exception('Exception when trying to connect to security scanner endpoint') raise Exception('Exception when trying to connect to security scanner endpoint') def analyze_layer(self, layer): """ Posts the given layer to the security scanner for analysis, blocking until complete. Returns the analysis version on success or raises an exception deriving from AnalyzeLayerException on failure. Callers should handle all cases of AnalyzeLayerException. """ request = self._new_analyze_request(layer) if not request: raise AnalyzeLayerException logger.info('Analyzing layer %s', request['Layer']['Name']) try: response = self._call('POST', _API_METHOD_INSERT, body=request) json_response = response.json() except requests.exceptions.Timeout: logger.exception('Timeout when trying to post layer data response for %s', layer.id) raise AnalyzeLayerRetryException except requests.exceptions.ConnectionError: logger.exception('Connection error when trying to post layer data response for %s', layer.id) raise AnalyzeLayerRetryException except (requests.exceptions.RequestException, ValueError) as re: logger.exception('Failed to post layer data response for %s: %s', layer.id, re) raise AnalyzeLayerException # Handle any errors from the security scanner. if response.status_code != 201: message = json_response.get('Error').get('Message', '') logger.warning('A warning event occurred when analyzing layer %s (status code %s): %s', request['Layer']['Name'], response.status_code, message) # 400 means the layer could not be analyzed due to a bad request. if response.status_code == 400: if message == UNKNOWN_PARENT_LAYER_ERROR_MSG: raise MissingParentLayerException('Bad request to security scanner: %s' % message) else: raise AnalyzeLayerException('Bad request to security scanner: %s' % message) # 422 means that the layer could not be analyzed: # - the layer could not be extracted (might be a manifest or an invalid .tar.gz) # - the layer operating system / package manager is unsupported elif response.status_code == 422: raise InvalidLayerException # Otherwise, it is some other error and we should retry. else: raise AnalyzeLayerRetryException # Return the parsed API version. return json_response['Layer']['IndexedByVersion'] def check_layer_vulnerable(self, layer_id, cve_name): """ Checks to see if the layer with the given ID is vulnerable to the specified CVE. """ layer_data = self._get_layer_data(layer_id, include_vulnerabilities=True) if layer_data is None or 'Layer' not in layer_data or 'Features' not in layer_data['Layer']: return False for feature in layer_data['Layer']['Features']: for vuln in feature.get('Vulnerabilities', []): if vuln['Name'] == cve_name: return True return False def get_notification(self, notification_name, layer_limit=100, page=None): """ Gets the data for a specific notification, with optional page token. Returns a tuple of the data (None on failure) and whether to retry. """ try: params = { 'limit': layer_limit } if page is not None: params['page'] = page response = self._call('GET', _API_METHOD_GET_NOTIFICATION % notification_name, params=params) json_response = response.json() except requests.exceptions.Timeout: logger.exception('Timeout when trying to get notification for %s', notification_name) return None, True except requests.exceptions.ConnectionError: logger.exception('Connection error when trying to get notification for %s', notification_name) return None, True except (requests.exceptions.RequestException, ValueError): logger.exception('Failed to get notification for %s', notification_name) return None, False if response.status_code != 200: return None, response.status_code != 404 and response.status_code != 400 return json_response, False def mark_notification_read(self, notification_name): """ Marks a security scanner notification as read. """ try: response = self._call('DELETE', _API_METHOD_MARK_NOTIFICATION_READ % notification_name) return response.status_code / 100 == 2 except requests.exceptions.RequestException: logger.exception('Failed to mark notification as read: %s', notification_name) return False def get_layer_data(self, layer, include_features=False, include_vulnerabilities=False): """ Returns the layer data for the specified layer. On error, returns None. """ layer_id = '%s.%s' % (layer.docker_image_id, layer.storage.uuid) return self._get_layer_data(layer_id, include_features, include_vulnerabilities) def _get_layer_data(self, layer_id, include_features=False, include_vulnerabilities=False): try: params = {} if include_features: params = {'features': True} if include_vulnerabilities: params = {'vulnerabilities': True} response = self._call('GET', _API_METHOD_GET_LAYER % layer_id, params=params) logger.debug('Got response %s for vulnerabilities for layer %s', response.status_code, layer_id) json_response = response.json() except requests.exceptions.Timeout: raise APIRequestFailure('API call timed out') except requests.exceptions.ConnectionError: raise APIRequestFailure('Could not connect to security service') except (requests.exceptions.RequestException, ValueError): logger.exception('Failed to get layer data response for %s', layer_id) raise APIRequestFailure() if response.status_code == 404: return None return json_response def _call(self, method, relative_url, params=None, body=None): """ Issues an HTTP call to the sec API at the given relative URL. This function disconnects from the database while awaiting a response from the API server. """ if self._config is None: raise Exception('Cannot call unconfigured security system') client = self._client headers = {'Connection': 'close'} timeout = self._config.get('SECURITY_SCANNER_API_TIMEOUT_SECONDS', 10) endpoint = self._config['SECURITY_SCANNER_ENDPOINT'] if method != 'GET': timeout = self._config.get('SECURITY_SCANNER_API_BATCH_TIMEOUT_SECONDS', timeout) endpoint = self._config.get('SECURITY_SCANNER_ENDPOINT_BATCH') or endpoint api_url = urljoin(endpoint, '/' + self._config.get('SECURITY_SCANNER_API_VERSION', 'v1')) + '/' url = urljoin(api_url, relative_url) signer_proxy_url = self._config.get('JWTPROXY_SIGNER', 'localhost:8080') with CloseForLongOperation(self._config): logger.debug('%sing security URL %s', method.upper(), url) return client.request(method, url, json=body, params=params, timeout=timeout, verify='/conf/mitm.cert', headers=headers, proxies={ 'https': 'https://' + signer_proxy_url, 'http': 'http://' + signer_proxy_url })