name : DataSourceEc2.py # Copyright (C) 2009-2010 Canonical Ltd. # Copyright (C) 2012 Hewlett-Packard Development Company, L.P. # Copyright (C) 2012 Yahoo! Inc. # # Author: Scott Moser <scott.moser@canonical.com> # Author: Juerg Hafliger <juerg.haefliger@hp.com> # Author: Joshua Harlow <harlowja@yahoo-inc.com> # # This file is part of cloud-init. See LICENSE file for license information. import copy import logging import os import time from typing import Dict, List from cloudinit import dmi, net, sources from cloudinit import url_helper as uhelp from cloudinit import util, warnings from cloudinit.distros import Distro from cloudinit.event import EventScope, EventType from cloudinit.net import netplan from cloudinit.net.dhcp import NoDHCPLeaseError from cloudinit.net.ephemeral import EphemeralIPNetwork from cloudinit.sources.helpers import ec2 LOG = logging.getLogger(__name__) SKIP_METADATA_URL_CODES = frozenset([uhelp.NOT_FOUND]) STRICT_ID_PATH = ("datasource", "Ec2", "strict_id") STRICT_ID_DEFAULT = "warn" class CloudNames: ALIYUN = "aliyun" AWS = "aws" BRIGHTBOX = "brightbox" ZSTACK = "zstack" E24CLOUD = "e24cloud" OUTSCALE = "outscale" # UNKNOWN indicates no positive id. If strict_id is 'warn' or 'false', # then an attempt at the Ec2 Metadata service will be made. UNKNOWN = "unknown" # NO_EC2_METADATA indicates this platform does not have a Ec2 metadata # service available. No attempt at the Ec2 Metadata service will be made. NO_EC2_METADATA = "no-ec2-metadata" # Drop when LP: #1988157 tag handling is fixed def skip_404_tag_errors(exception): return exception.code == 404 and "meta-data/tags/" in exception.url # Cloud platforms that support IMDSv2 style metadata server IDMSV2_SUPPORTED_CLOUD_PLATFORMS = [CloudNames.AWS, CloudNames.ALIYUN] # Only trigger hook-hotplug on NICs with Ec2 drivers. Avoid triggering # it on docker virtual NICs and the like. LP: #1946003 _EXTRA_HOTPLUG_UDEV_RULES = """ ENV{ID_NET_DRIVER}=="vif|ena|ixgbevf", GOTO="cloudinit_hook" GOTO="cloudinit_end" """ class DataSourceEc2(sources.DataSource): dsname = "Ec2" # Default metadata urls that will be used if none are provided # They will be checked for 'resolveability' and some of the # following may be discarded if they do not resolve metadata_urls = [ "http://169.254.169.254", "http://[fd00:ec2::254]", "http://instance-data.:8773", ] # The minimum supported metadata_version from the ec2 metadata apis min_metadata_version = "2009-04-04" # Priority ordered list of additional metadata versions which will be tried # for extended metadata content. IPv6 support comes in 2016-09-02. # Tags support comes in 2021-03-23. extended_metadata_versions: List[str] = [ "2021-03-23", "2018-09-24", "2016-09-02", ] # Setup read_url parameters per get_url_params. url_max_wait = 120 url_timeout = 50 _api_token = None # API token for accessing the metadata service _network_config = sources.UNSET # Used to cache calculated network cfg v1 # Whether we want to get network configuration from the metadata service. perform_dhcp_setup = False supported_update_events = { EventScope.NETWORK: { EventType.BOOT_NEW_INSTANCE, EventType.BOOT, EventType.BOOT_LEGACY, EventType.HOTPLUG, } } default_update_events = { EventScope.NETWORK: { EventType.BOOT_NEW_INSTANCE, EventType.HOTPLUG, } } extra_hotplug_udev_rules = _EXTRA_HOTPLUG_UDEV_RULES def __init__(self, sys_cfg, distro, paths): super(DataSourceEc2, self).__init__(sys_cfg, distro, paths) self.metadata_address = None def _unpickle(self, ci_pkl_version: int) -> None: super()._unpickle(ci_pkl_version) self.extra_hotplug_udev_rules = _EXTRA_HOTPLUG_UDEV_RULES def _get_cloud_name(self): """Return the cloud name as identified during _get_data.""" return identify_platform() def _get_data(self): strict_mode, _sleep = read_strict_mode( util.get_cfg_by_path( self.sys_cfg, STRICT_ID_PATH, STRICT_ID_DEFAULT ), ("warn", None), ) LOG.debug( "strict_mode: %s, cloud_name=%s cloud_platform=%s", strict_mode, self.cloud_name, self.platform, ) if strict_mode == "true" and self.cloud_name == CloudNames.UNKNOWN: return False elif self.cloud_name == CloudNames.NO_EC2_METADATA: return False if self.perform_dhcp_setup: # Setup networking in init-local stage. if util.is_FreeBSD(): LOG.debug("FreeBSD doesn't support running dhclient with -sf") return False try: with EphemeralIPNetwork( self.distro, self.distro.fallback_interface, ipv4=True, ipv6=True, ) as netw: state_msg = f" {netw.state_msg}" if netw.state_msg else "" self._crawled_metadata = util.log_time( logfunc=LOG.debug, msg=f"Crawl of metadata service{state_msg}", func=self.crawl_metadata, ) except NoDHCPLeaseError: return False else: self._crawled_metadata = util.log_time( logfunc=LOG.debug, msg="Crawl of metadata service", func=self.crawl_metadata, ) if not self._crawled_metadata: return False self.metadata = self._crawled_metadata.get("meta-data", None) self.userdata_raw = self._crawled_metadata.get("user-data", None) self.identity = ( self._crawled_metadata.get("dynamic", {}) .get("instance-identity", {}) .get("document", {}) ) return True def is_classic_instance(self): """Report if this instance type is Ec2 Classic (non-vpc).""" if not self.metadata: # Can return False on inconclusive as we are also called in # network_config where metadata will be present. # Secondary call site is in packaging postinst script. return False ifaces_md = self.metadata.get("network", {}).get("interfaces", {}) for _mac, mac_data in ifaces_md.get("macs", {}).items(): if "vpc-id" in mac_data: return False return True @property def launch_index(self): if not self.metadata: return None return self.metadata.get("ami-launch-index") @property def platform(self): # Handle upgrade path of pickled ds if not hasattr(self, "_platform_type"): self._platform_type = DataSourceEc2.dsname.lower() if not self._platform_type: self._platform_type = DataSourceEc2.dsname.lower() return self._platform_type # IMDSv2 related parameters from the ec2 metadata api document @property def api_token_route(self): return "latest/api/token" @property def imdsv2_token_ttl_seconds(self): return "21600" @property def imdsv2_token_put_header(self): return "X-aws-ec2-metadata-token" @property def imdsv2_token_req_header(self): return self.imdsv2_token_put_header + "-ttl-seconds" @property def imdsv2_token_redact(self): return [self.imdsv2_token_put_header, self.imdsv2_token_req_header] def get_metadata_api_version(self): """Get the best supported api version from the metadata service. Loop through all extended support metadata versions in order and return the most-fully featured metadata api version discovered. If extended_metadata_versions aren't present, return the datasource's min_metadata_version. """ # Assumes metadata service is already up url_tmpl = "{0}/{1}/meta-data/instance-id" headers = self._get_headers() for api_ver in self.extended_metadata_versions: url = url_tmpl.format(self.metadata_address, api_ver) try: resp = uhelp.readurl( url=url, headers=headers, headers_redact=self.imdsv2_token_redact, ) except uhelp.UrlError as e: LOG.debug("url %s raised exception %s", url, e) else: if resp.code == 200: LOG.debug("Found preferred metadata version %s", api_ver) return api_ver elif resp.code == 404: msg = "Metadata api version %s not present. Headers: %s" LOG.debug(msg, api_ver, resp.headers) return self.min_metadata_version def get_instance_id(self): if self.cloud_name == CloudNames.AWS: # Prefer the ID from the instance identity document, but fall back if not getattr(self, "identity", None): # If re-using cached datasource, it's get_data run didn't # setup self.identity. So we need to do that now. api_version = self.get_metadata_api_version() self.identity = ec2.get_instance_identity( api_version, self.metadata_address, headers_cb=self._get_headers, headers_redact=self.imdsv2_token_redact, exception_cb=self._refresh_stale_aws_token_cb, ).get("document", {}) return self.identity.get( "instanceId", self.metadata["instance-id"] ) else: return self.metadata["instance-id"] def _maybe_fetch_api_token(self, mdurls): """Get an API token for EC2 Instance Metadata Service. On EC2. IMDS will always answer an API token, unless the instance owner has disabled the IMDS HTTP endpoint or the network topology conflicts with the configured hop-limit. """ if self.cloud_name not in IDMSV2_SUPPORTED_CLOUD_PLATFORMS: return urls = [] url2base = {} url_path = self.api_token_route request_method = "PUT" for url in mdurls: cur = "{0}/{1}".format(url, url_path) urls.append(cur) url2base[cur] = url # use the self._imds_exception_cb to check for Read errors LOG.debug("Fetching Ec2 IMDSv2 API Token") response = None url = None url_params = self.get_url_params() try: url, response = uhelp.wait_for_url( urls=urls, max_wait=url_params.max_wait_seconds, timeout=url_params.timeout_seconds, status_cb=LOG.warning, headers_cb=self._get_headers, exception_cb=self._imds_exception_cb, request_method=request_method, headers_redact=self.imdsv2_token_redact, connect_synchronously=False, ) except uhelp.UrlError: # We use the raised exception to interrupt the retry loop. # Nothing else to do here. pass if url and response: self._api_token = response return url2base[url] # If we get here, then wait_for_url timed out, waiting for IMDS # or the IMDS HTTP endpoint is disabled return None def wait_for_metadata_service(self): mcfg = self.ds_cfg url_params = self.get_url_params() if url_params.max_wait_seconds <= 0: return False # Remove addresses from the list that wont resolve. mdurls = mcfg.get("metadata_urls", self.metadata_urls) filtered = [x for x in mdurls if util.is_resolvable_url(x)] if set(filtered) != set(mdurls): LOG.debug( "Removed the following from metadata urls: %s", list((set(mdurls) - set(filtered))), ) if len(filtered): mdurls = filtered else: LOG.warning("Empty metadata url list! using default list") mdurls = self.metadata_urls # try the api token path first metadata_address = self._maybe_fetch_api_token(mdurls) # When running on EC2, we always access IMDS with an API token. # If we could not get an API token, then we assume the IMDS # endpoint was disabled and we move on without a data source. # Fallback to IMDSv1 if not running on EC2 if ( not metadata_address and self.cloud_name not in IDMSV2_SUPPORTED_CLOUD_PLATFORMS ): # if we can't get a token, use instance-id path urls = [] url2base = {} url_path = "{ver}/meta-data/instance-id".format( ver=self.min_metadata_version ) request_method = "GET" for url in mdurls: cur = "{0}/{1}".format(url, url_path) urls.append(cur) url2base[cur] = url start_time = time.time() url, _ = uhelp.wait_for_url( urls=urls, max_wait=url_params.max_wait_seconds, timeout=url_params.timeout_seconds, status_cb=LOG.warning, headers_redact=self.imdsv2_token_redact, headers_cb=self._get_headers, request_method=request_method, ) if url: metadata_address = url2base[url] if metadata_address: self.metadata_address = metadata_address LOG.debug("Using metadata source: '%s'", self.metadata_address) elif self.cloud_name in IDMSV2_SUPPORTED_CLOUD_PLATFORMS: LOG.warning("IMDS's HTTP endpoint is probably disabled") else: LOG.critical( "Giving up on md from %s after %s seconds", urls, int(time.time() - start_time), ) return bool(metadata_address) def device_name_to_device(self, name): # Consult metadata service, that has # ephemeral0: sdb # and return 'sdb' for input 'ephemeral0' if "block-device-mapping" not in self.metadata: return None # Example: # 'block-device-mapping': # {'ami': '/dev/sda1', # 'ephemeral0': '/dev/sdb', # 'root': '/dev/sda1'} found = None bdm = self.metadata["block-device-mapping"] if not isinstance(bdm, dict): LOG.debug("block-device-mapping not a dictionary: '%s'", bdm) return None for entname, device in bdm.items(): if entname == name: found = device break # LP: #513842 mapping in Euca has 'ephemeral' not 'ephemeral0' if entname == "ephemeral" and name == "ephemeral0": found = device if found is None: LOG.debug("Unable to convert %s to a device", name) return None ofound = found if not found.startswith("/"): found = "/dev/%s" % found if os.path.exists(found): return found remapped = self._remap_device(os.path.basename(found)) if remapped: LOG.debug("Remapped device name %s => %s", found, remapped) return remapped # On t1.micro, ephemeral0 will appear in block-device-mapping from # metadata, but it will not exist on disk (and never will) # at this point, we've verified that the path did not exist # in the special case of 'ephemeral0' return None to avoid bogus # fstab entry (LP: #744019) if name == "ephemeral0": return None return ofound @property def availability_zone(self): try: if self.cloud_name == CloudNames.AWS: return self.identity.get( "availabilityZone", self.metadata["placement"]["availability-zone"], ) else: return self.metadata["placement"]["availability-zone"] except KeyError: return None @property def region(self): if self.cloud_name == CloudNames.AWS: region = self.identity.get("region") # Fallback to trimming the availability zone if region is missing if self.availability_zone and not region: region = self.availability_zone[:-1] return region else: az = self.availability_zone if az is not None: return az[:-1] return None def activate(self, cfg, is_new_instance): if not is_new_instance: return if self.cloud_name == CloudNames.UNKNOWN: warn_if_necessary( util.get_cfg_by_path(cfg, STRICT_ID_PATH, STRICT_ID_DEFAULT), cfg, ) @property def network_config(self): """Return a network config dict for rendering ENI or netplan files.""" if self._network_config != sources.UNSET: return self._network_config if self.metadata is None: # this would happen if get_data hadn't been called. leave as UNSET LOG.warning( "Unexpected call to network_config when metadata is None." ) return None result = None no_network_metadata_on_aws = bool( "network" not in self.metadata and self.cloud_name == CloudNames.AWS ) if no_network_metadata_on_aws: LOG.debug( "Metadata 'network' not present:" " Refreshing stale metadata from prior to upgrade." ) util.log_time( logfunc=LOG.debug, msg="Re-crawl of metadata service", func=self.get_data, ) iface = self.distro.fallback_interface net_md = self.metadata.get("network") if isinstance(net_md, dict): # SRU_BLOCKER: xenial, bionic and eoan should default # apply_full_imds_network_config to False to retain original # behavior on those releases. result = convert_ec2_metadata_network_config( net_md, self.distro, fallback_nic=iface, full_network_config=util.get_cfg_option_bool( self.ds_cfg, "apply_full_imds_network_config", True ), ) # Non-VPC (aka Classic) Ec2 instances need to rewrite the # network config file every boot due to MAC address change. if self.is_classic_instance(): self.default_update_events = copy.deepcopy( self.default_update_events ) self.default_update_events[EventScope.NETWORK].add( EventType.BOOT ) self.default_update_events[EventScope.NETWORK].add( EventType.BOOT_LEGACY ) else: LOG.warning("Metadata 'network' key not valid: %s.", net_md) self._network_config = result return self._network_config def crawl_metadata(self): """Crawl metadata service when available. @returns: Dictionary of crawled metadata content containing the keys: meta-data, user-data and dynamic. """ if not self.wait_for_metadata_service(): return {} api_version = self.get_metadata_api_version() redact = self.imdsv2_token_redact crawled_metadata = {} if self.cloud_name in IDMSV2_SUPPORTED_CLOUD_PLATFORMS: exc_cb = self._refresh_stale_aws_token_cb exc_cb_ud = self._skip_or_refresh_stale_aws_token_cb skip_cb = None elif self.cloud_name == CloudNames.OUTSCALE: exc_cb = exc_cb_ud = None skip_cb = skip_404_tag_errors else: exc_cb = exc_cb_ud = skip_cb = None try: raw_userdata = ec2.get_instance_userdata( api_version, self.metadata_address, headers_cb=self._get_headers, headers_redact=redact, exception_cb=exc_cb_ud, ) crawled_metadata["user-data"] = util.maybe_b64decode(raw_userdata) crawled_metadata["meta-data"] = ec2.get_instance_metadata( api_version, self.metadata_address, headers_cb=self._get_headers, headers_redact=redact, exception_cb=exc_cb, retrieval_exception_ignore_cb=skip_cb, ) if self.cloud_name == CloudNames.AWS: identity = ec2.get_instance_identity( api_version, self.metadata_address, headers_cb=self._get_headers, headers_redact=redact, exception_cb=exc_cb, ) crawled_metadata["dynamic"] = {"instance-identity": identity} except Exception: util.logexc( LOG, "Failed reading from metadata address %s", self.metadata_address, ) return {} crawled_metadata["_metadata_api_version"] = api_version return crawled_metadata def _refresh_api_token(self, seconds=None): """Request new metadata API token. @param seconds: The lifetime of the token in seconds @return: The API token or None if unavailable. """ if self.cloud_name not in IDMSV2_SUPPORTED_CLOUD_PLATFORMS: return None if seconds is None: seconds = self.imdsv2_token_ttl_seconds LOG.debug("Refreshing Ec2 metadata API token") request_header = {self.imdsv2_token_req_header: seconds} token_url = "{}/{}".format(self.metadata_address, self.api_token_route) try: response = uhelp.readurl( token_url, headers=request_header, headers_redact=self.imdsv2_token_redact, request_method="PUT", ) except uhelp.UrlError as e: LOG.warning( "Unable to get API token: %s raised exception %s", token_url, e ) return None return response.contents def _skip_or_refresh_stale_aws_token_cb(self, msg, exception): """Callback will not retry on SKIP_USERDATA_CODES or if no token is available.""" retry = ec2.skip_retry_on_codes( ec2.SKIP_USERDATA_CODES, msg, exception ) if not retry: return False # False raises exception return self._refresh_stale_aws_token_cb(msg, exception) def _refresh_stale_aws_token_cb(self, msg, exception): """Exception handler for Ec2 to refresh token if token is stale.""" if isinstance(exception, uhelp.UrlError) and exception.code == 401: # With _api_token as None, _get_headers will _refresh_api_token. LOG.debug("Clearing cached Ec2 API token due to expiry") self._api_token = None return True # always retry def _imds_exception_cb(self, msg, exception=None): """Fail quickly on proper AWS if IMDSv2 rejects API token request Guidance from Amazon is that if IMDSv2 had disabled token requests by returning a 403, or cloud-init malformed requests resulting in other 40X errors, we want the datasource detection to fail quickly without retries as those symptoms will likely not be resolved by retries. Exceptions such as requests.ConnectionError due to IMDS being temporarily unroutable or unavailable will still retry due to the callsite wait_for_url. """ if isinstance(exception, uhelp.UrlError): # requests.ConnectionError will have exception.code == None if exception.code and exception.code >= 400: if exception.code == 403: LOG.warning( "Ec2 IMDS endpoint returned a 403 error. " "HTTP endpoint is disabled. Aborting." ) else: LOG.warning( "Fatal error while requesting Ec2 IMDSv2 API tokens" ) raise exception def _get_headers(self, url=""): """Return a dict of headers for accessing a url. If _api_token is unset on AWS, attempt to refresh the token via a PUT and then return the updated token header. """ if self.cloud_name not in IDMSV2_SUPPORTED_CLOUD_PLATFORMS: return {} # Request a 6 hour token if URL is api_token_route request_token_header = { self.imdsv2_token_req_header: self.imdsv2_token_ttl_seconds } if self.api_token_route in url: return request_token_header if not self._api_token: # If we don't yet have an API token, get one via a PUT against # api_token_route. This _api_token may get unset by a 403 due # to an invalid or expired token self._api_token = self._refresh_api_token() if not self._api_token: return {} return {self.imdsv2_token_put_header: self._api_token} class DataSourceEc2Local(DataSourceEc2): """Datasource run at init-local which sets up network to query metadata. In init-local, no network is available. This subclass sets up minimal networking with dhclient on a viable nic so that it can talk to the metadata service. If the metadata service provides network configuration then render the network configuration for that instance based on metadata. """ perform_dhcp_setup = True # Use dhcp before querying metadata def get_data(self): supported_platforms = (CloudNames.AWS, CloudNames.OUTSCALE) if self.cloud_name not in supported_platforms: LOG.debug( "Local Ec2 mode only supported on %s, not %s", supported_platforms, self.cloud_name, ) return False return super(DataSourceEc2Local, self).get_data() def read_strict_mode(cfgval, default): try: return parse_strict_mode(cfgval) except ValueError as e: LOG.warning(e) return default def parse_strict_mode(cfgval): # given a mode like: # true, false, warn,[sleep] # return tuple with string mode (true|false|warn) and sleep. if cfgval is True: return "true", None if cfgval is False: return "false", None if not cfgval: return "warn", 0 mode, _, sleep = cfgval.partition(",") if mode not in ("true", "false", "warn"): raise ValueError( "Invalid mode '%s' in strict_id setting '%s': " "Expected one of 'true', 'false', 'warn'." % (mode, cfgval) ) if sleep: try: sleep = int(sleep) except ValueError as e: raise ValueError( "Invalid sleep '%s' in strict_id setting '%s': not an integer" % (sleep, cfgval) ) from e else: sleep = None return mode, sleep def warn_if_necessary(cfgval, cfg): try: mode, sleep = parse_strict_mode(cfgval) except ValueError as e: LOG.warning(e) return if mode == "false": return warnings.show_warning("non_ec2_md", cfg, mode=True, sleep=sleep) def identify_aliyun(data): if data["product_name"] == "Alibaba Cloud ECS": return CloudNames.ALIYUN def identify_aws(data): # data is a dictionary returned by _collect_platform_data. if data["uuid"].startswith("ec2") and ( data["uuid_source"] == "hypervisor" or data["uuid"] == data["serial"] ): return CloudNames.AWS return None def identify_brightbox(data): if data["serial"].endswith(".brightbox.com"): return CloudNames.BRIGHTBOX def identify_zstack(data): if data["asset_tag"].endswith(".zstack.io"): return CloudNames.ZSTACK def identify_e24cloud(data): if data["vendor"] == "e24cloud": return CloudNames.E24CLOUD def identify_outscale(data): if ( data["product_name"] == "3DS Outscale VM".lower() and data["vendor"] == "3DS Outscale".lower() ): return CloudNames.OUTSCALE def identify_platform(): # identify the platform and return an entry in CloudNames. data = _collect_platform_data() checks = ( identify_aws, identify_brightbox, identify_zstack, identify_e24cloud, identify_outscale, identify_aliyun, lambda x: CloudNames.UNKNOWN, ) for checker in checks: try: result = checker(data) if result: return result except Exception as e: LOG.warning( "calling %s with %s raised exception: %s", checker, data, e ) def _collect_platform_data(): """Returns a dictionary of platform info from dmi or /sys/hypervisor. Keys in the dictionary are as follows: uuid: system-uuid from dmi or /sys/hypervisor uuid_source: 'hypervisor' (/sys/hypervisor/uuid) or 'dmi' serial: dmi 'system-serial-number' (/sys/.../product_serial) asset_tag: 'dmidecode -s chassis-asset-tag' vendor: dmi 'system-manufacturer' (/sys/.../sys_vendor) product_name: dmi 'system-product-name' (/sys/.../system-manufacturer) On Ec2 instances experimentation is that product_serial is upper case, and product_uuid is lower case. This returns lower case values for both. """ data = {} try: uuid = util.load_text_file("/sys/hypervisor/uuid").strip() data["uuid_source"] = "hypervisor" except Exception: uuid = dmi.read_dmi_data("system-uuid") data["uuid_source"] = "dmi" if uuid is None: uuid = "" data["uuid"] = uuid.lower() serial = dmi.read_dmi_data("system-serial-number") if serial is None: serial = "" data["serial"] = serial.lower() asset_tag = dmi.read_dmi_data("chassis-asset-tag") if asset_tag is None: asset_tag = "" data["asset_tag"] = asset_tag.lower() vendor = dmi.read_dmi_data("system-manufacturer") data["vendor"] = (vendor if vendor else "").lower() product_name = dmi.read_dmi_data("system-product-name") data["product_name"] = (product_name if product_name else "").lower() return data def _build_nic_order( macs_metadata: Dict[str, Dict], macs: List[str] ) -> Dict[str, int]: """ Builds a dictionary containing macs as keys nad nic orders as values, taking into account `network-card` and `device-number` if present. Note that the first NIC will be the primary NIC as it will be the one with [network-card] == 0 and device-number == 0 if present. @param macs_metadata: dictionary with mac address as key and contents like: {"device-number": "0", "interface-id": "...", "local-ipv4s": ...} @macs: list of macs to consider @return: Dictionary with macs as keys and nic orders as values. """ nic_order: Dict[str, int] = {} if len(macs) == 0 or len(macs_metadata) == 0: return nic_order valid_macs_metadata = filter( # filter out nics without metadata (not a physical nic) lambda mmd: mmd[1] is not None, # filter by macs map(lambda mac: (mac, macs_metadata.get(mac)), macs), ) def _get_key_as_int_or(dikt, key, alt_value): value = dikt.get(key, None) if value is not None: return int(value) return alt_value # Sort by (network_card, device_index) as some instances could have # multiple network cards with repeated device indexes. # # On platforms where network-card and device-number are not present, # as AliYun, the order will be by mac, as before the introduction of this # function. return { mac: i for i, (mac, _mac_metadata) in enumerate( sorted( valid_macs_metadata, key=lambda mmd: ( _get_key_as_int_or( mmd[1], "network-card", float("infinity") ), _get_key_as_int_or( mmd[1], "device-number", float("infinity") ), ), ) ) } def _configure_policy_routing( dev_config: dict, *, nic_name: str, nic_metadata: dict, distro: Distro, is_ipv4: bool, table: int, ) -> None: """ Configure policy-based routing on secondary NICs / secondary IPs to ensure outgoing packets are routed via the correct interface. @param: dev_config: network cfg v2 to be updated inplace. @param: nic_name: nic name. Only used if ipv4. @param: nic_metadata: nic metadata from IMDS. @param: distro: Instance of Distro. Only used if ipv4. @param: is_ipv4: Boolean indicating if we are acting over ipv4 or not. @param: table: Routing table id. """ if is_ipv4: subnet_prefix_routes = nic_metadata.get("subnet-ipv4-cidr-block") ips = nic_metadata.get("local-ipv4s") else: subnet_prefix_routes = nic_metadata.get("subnet-ipv6-cidr-blocks") ips = nic_metadata.get("ipv6s") if not (subnet_prefix_routes and ips): LOG.debug( "Not enough IMDS information to configure policy routing " "for IPv%s", "4" if is_ipv4 else "6", ) return if not dev_config.get("routes"): dev_config["routes"] = [] if is_ipv4: try: lease = distro.dhcp_client.dhcp_discovery(nic_name, distro=distro) gateway = lease["routers"] except NoDHCPLeaseError as e: LOG.warning( "Could not perform dhcp discovery on %s to find its " "gateway. Not adding default route via the gateway. " "Error: %s", nic_name, e, ) else: # Add default route via the NIC's gateway dev_config["routes"].append( { "to": "0.0.0.0/0", "via": gateway, "table": table, }, ) subnet_prefix_routes = ( [subnet_prefix_routes] if isinstance(subnet_prefix_routes, str) else subnet_prefix_routes ) for prefix_route in subnet_prefix_routes: dev_config["routes"].append( { "to": prefix_route, "table": table, }, ) if not dev_config.get("routing-policy"): dev_config["routing-policy"] = [] # Packets coming from any IP associated with the current NIC # will be routed using `table` routing table ips = [ips] if isinstance(ips, str) else ips for ip in ips: dev_config["routing-policy"].append( { "from": ip, "table": table, }, ) def convert_ec2_metadata_network_config( network_md, distro, macs_to_nics=None, fallback_nic=None, full_network_config=True, ): """Convert ec2 metadata to network config version 2 data dict. @param: network_md: 'network' portion of EC2 metadata. generally formed as {"interfaces": {"macs": {}} where 'macs' is a dictionary with mac address as key and contents like: {"device-number": "0", "interface-id": "...", "local-ipv4s": ...} @param: distro: instance of Distro. @param: macs_to_nics: Optional dict of mac addresses and nic names. If not provided, get_interfaces_by_mac is called to get it from the OS. @param: fallback_nic: Optionally provide the primary nic interface name. This nic will be guaranteed to minimally have a dhcp4 configuration. @param: full_network_config: Boolean set True to configure all networking presented by IMDS. This includes rendering secondary IPv4 and IPv6 addresses on all NICs and rendering network config on secondary NICs. If False, only the primary nic will be configured and only with dhcp (IPv4/IPv6). @return A dict of network config version 2 based on the metadata and macs. """ netcfg = {"version": 2, "ethernets": {}} if not macs_to_nics: macs_to_nics = net.get_interfaces_by_mac() macs_metadata = network_md["interfaces"]["macs"] if not full_network_config: for mac, nic_name in macs_to_nics.items(): if nic_name == fallback_nic: break dev_config = { "dhcp4": True, "dhcp6": False, "match": {"macaddress": mac.lower()}, "set-name": nic_name, } nic_metadata = macs_metadata.get(mac) if nic_metadata.get("ipv6s"): # Any IPv6 addresses configured dev_config["dhcp6"] = True netcfg["ethernets"][nic_name] = dev_config return netcfg # Apply network config for all nics and any secondary IPv4/v6 addresses is_netplan = isinstance(distro.network_renderer, netplan.Renderer) macs = sorted(macs_to_nics.keys()) nic_order = _build_nic_order(macs_metadata, macs) for mac in macs: nic_name = macs_to_nics[mac] nic_metadata = macs_metadata.get(mac) if not nic_metadata: continue # Not a physical nic represented in metadata nic_idx = nic_order[mac] is_primary_nic = nic_idx == 0 # nic_idx + 1 to start route_metric at 100 (nic_idx is 0-indexed) dhcp_override = {"route-metric": (nic_idx + 1) * 100} dev_config = { "dhcp4": True, "dhcp4-overrides": dhcp_override, "dhcp6": False, "match": {"macaddress": mac.lower()}, "set-name": nic_name, } # This config only works on systems using Netplan because Networking # config V2 does not support `routing-policy`, but this config is # passed through on systems using Netplan. # See: https://github.com/canonical/cloud-init/issues/4862 # # If device-number is not present (AliYun or other ec2-like platforms), # do not configure source-routing as we cannot determine which is the # primary NIC. table = 100 + nic_idx if ( is_netplan and nic_metadata.get("device-number") and not is_primary_nic ): dhcp_override["use-routes"] = True _configure_policy_routing( dev_config, distro=distro, nic_name=nic_name, nic_metadata=nic_metadata, is_ipv4=True, table=table, ) if nic_metadata.get("ipv6s"): # Any IPv6 addresses configured dev_config["dhcp6"] = True dev_config["dhcp6-overrides"] = dhcp_override if ( is_netplan and nic_metadata.get("device-number") and not is_primary_nic ): _configure_policy_routing( dev_config, distro=distro, nic_name=nic_name, nic_metadata=nic_metadata, is_ipv4=False, table=table, ) dev_config["addresses"] = get_secondary_addresses(nic_metadata, mac) if not dev_config["addresses"]: dev_config.pop("addresses") # Since we found none configured netcfg["ethernets"][nic_name] = dev_config # Remove route-metric dhcp overrides and routes / routing-policy if only # one nic configured if len(netcfg["ethernets"]) == 1: for nic_name in netcfg["ethernets"].keys(): netcfg["ethernets"][nic_name].pop("dhcp4-overrides") netcfg["ethernets"][nic_name].pop("dhcp6-overrides", None) netcfg["ethernets"][nic_name].pop("routes", None) netcfg["ethernets"][nic_name].pop("routing-policy", None) return netcfg def get_secondary_addresses(nic_metadata, mac): """Parse interface-specific nic metadata and return any secondary IPs :return: List of secondary IPv4 or IPv6 addresses to configure on the interface """ ipv4s = nic_metadata.get("local-ipv4s") ipv6s = nic_metadata.get("ipv6s") addresses = [] # In version < 2018-09-24 local_ipv4s or ipv6s is a str with one IP if bool(isinstance(ipv4s, list) and len(ipv4s) > 1): addresses.extend( _get_secondary_addresses( nic_metadata, "subnet-ipv4-cidr-block", mac, ipv4s, "24" ) ) if bool(isinstance(ipv6s, list) and len(ipv6s) > 1): addresses.extend( _get_secondary_addresses( nic_metadata, "subnet-ipv6-cidr-block", mac, ipv6s, "128" ) ) return sorted(addresses) def _get_secondary_addresses(nic_metadata, cidr_key, mac, ips, default_prefix): """Return list of IP addresses as CIDRs for secondary IPs The CIDR prefix will be default_prefix if cidr_key is absent or not parseable in nic_metadata. """ addresses = [] cidr = nic_metadata.get(cidr_key) prefix = default_prefix if not cidr or len(cidr.split("/")) != 2: ip_type = "ipv4" if "ipv4" in cidr_key else "ipv6" LOG.warning( "Could not parse %s %s for mac %s. %s network" " config prefix defaults to /%s", cidr_key, cidr, mac, ip_type, prefix, ) else: prefix = cidr.split("/")[1] # We know we have > 1 ips for in metadata for this IP type for ip in ips[1:]: addresses.append("{ip}/{prefix}".format(ip=ip, prefix=prefix)) return addresses # Used to match classes to dependencies datasources = [ (DataSourceEc2Local, (sources.DEP_FILESYSTEM,)), # Run at init-local (DataSourceEc2, (sources.DEP_FILESYSTEM, sources.DEP_NETWORK)), ] # Return a list of data sources that match this set of dependencies def get_datasource_list(depends): return sources.list_from_depends(depends, datasources)