# vi: ts=4 expandtab # # Copyright (C) 2012 Canonical Ltd. # Copyright (C) 2012, 2013 Hewlett-Packard Development Company, L.P. # Copyright (C) 2012 Yahoo! Inc. # # Author: Scott Moser # Author: Juerg Haefliger # Author: Joshua Harlow # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License version 3, as # published by the Free Software Foundation. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . import contextlib import copy as obj_copy import ctypes import email import errno import glob import grp import gzip import hashlib import json import os import os.path import platform import pwd import random import re import shutil import socket import stat import string import subprocess import sys import tempfile import time from base64 import b64decode, b64encode from six.moves.urllib import parse as urlparse import six import yaml from cloudinit import importer from cloudinit import log as logging from cloudinit import mergers from cloudinit import safeyaml from cloudinit import type_utils from cloudinit import url_helper from cloudinit import version from cloudinit.settings import (CFG_BUILTIN) _DNS_REDIRECT_IP = None LOG = logging.getLogger(__name__) # Helps cleanup filenames to ensure they aren't FS incompatible FN_REPLACEMENTS = { os.sep: '_', } FN_ALLOWED = ('_-.()' + string.digits + string.ascii_letters) TRUE_STRINGS = ('true', '1', 'on', 'yes') FALSE_STRINGS = ('off', '0', 'no', 'false') # Helper utils to see if running in a container CONTAINER_TESTS = (['systemd-detect-virt', '--quiet', '--container'], ['running-in-container'], ['lxc-is-container']) PROC_CMDLINE = None def decode_binary(blob, encoding='utf-8'): # Converts a binary type into a text type using given encoding. if isinstance(blob, six.text_type): return blob return blob.decode(encoding) def encode_text(text, encoding='utf-8'): # Converts a text string into a binary type using given encoding. if isinstance(text, six.binary_type): return text return text.encode(encoding) def b64d(source): # Base64 decode some data, accepting bytes or unicode/str, and returning # str/unicode if the result is utf-8 compatible, otherwise returning bytes. decoded = b64decode(source) try: return decoded.decode('utf-8') except UnicodeDecodeError: return decoded def b64e(source): # Base64 encode some data, accepting bytes or unicode/str, and returning # str/unicode if the result is utf-8 compatible, otherwise returning bytes. if not isinstance(source, bytes): source = source.encode('utf-8') return b64encode(source).decode('utf-8') def fully_decoded_payload(part): # In Python 3, decoding the payload will ironically hand us a bytes object. # 'decode' means to decode according to Content-Transfer-Encoding, not # according to any charset in the Content-Type. So, if we end up with # bytes, first try to decode to str via CT charset, and failing that, try # utf-8 using surrogate escapes. cte_payload = part.get_payload(decode=True) if (six.PY3 and part.get_content_maintype() == 'text' and isinstance(cte_payload, bytes)): charset = part.get_charset() if charset and charset.input_codec: encoding = charset.input_codec else: encoding = 'utf-8' return cte_payload.decode(encoding, errors='surrogateescape') return cte_payload # Path for DMI Data DMI_SYS_PATH = "/sys/class/dmi/id" # dmidecode and /sys/class/dmi/id/* use different names for the same value, # this allows us to refer to them by one canonical name DMIDECODE_TO_DMI_SYS_MAPPING = { 'baseboard-asset-tag': 'board_asset_tag', 'baseboard-manufacturer': 'board_vendor', 'baseboard-product-name': 'board_name', 'baseboard-serial-number': 'board_serial', 'baseboard-version': 'board_version', 'bios-release-date': 'bios_date', 'bios-vendor': 'bios_vendor', 'bios-version': 'bios_version', 'chassis-asset-tag': 'chassis_asset_tag', 'chassis-manufacturer': 'chassis_vendor', 'chassis-serial-number': 'chassis_serial', 'chassis-version': 'chassis_version', 'system-manufacturer': 'sys_vendor', 'system-product-name': 'product_name', 'system-serial-number': 'product_serial', 'system-uuid': 'product_uuid', 'system-version': 'product_version', } class ProcessExecutionError(IOError): MESSAGE_TMPL = ('%(description)s\n' 'Command: %(cmd)s\n' 'Exit code: %(exit_code)s\n' 'Reason: %(reason)s\n' 'Stdout: %(stdout)r\n' 'Stderr: %(stderr)r') def __init__(self, stdout=None, stderr=None, exit_code=None, cmd=None, description=None, reason=None): if not cmd: self.cmd = '-' else: self.cmd = cmd if not description: self.description = 'Unexpected error while running command.' else: self.description = description if not isinstance(exit_code, six.integer_types): self.exit_code = '-' else: self.exit_code = exit_code if not stderr: self.stderr = '' else: self.stderr = stderr if not stdout: self.stdout = '' else: self.stdout = stdout if reason: self.reason = reason else: self.reason = '-' message = self.MESSAGE_TMPL % { 'description': self.description, 'cmd': self.cmd, 'exit_code': self.exit_code, 'stdout': self.stdout, 'stderr': self.stderr, 'reason': self.reason, } IOError.__init__(self, message) # For backward compatibility with Python 2. if not hasattr(self, 'message'): self.message = message class SeLinuxGuard(object): def __init__(self, path, recursive=False): # Late import since it might not always # be possible to use this try: self.selinux = importer.import_module('selinux') except ImportError: self.selinux = None self.path = path self.recursive = recursive def __enter__(self): if self.selinux and self.selinux.is_selinux_enabled(): return True else: return False def __exit__(self, excp_type, excp_value, excp_traceback): if not self.selinux or not self.selinux.is_selinux_enabled(): return if not os.path.lexists(self.path): return path = os.path.realpath(self.path) # path should be a string, not unicode if six.PY2: path = str(path) try: stats = os.lstat(path) self.selinux.matchpathcon(path, stats[stat.ST_MODE]) except OSError: return LOG.debug("Restoring selinux mode for %s (recursive=%s)", path, self.recursive) self.selinux.restorecon(path, recursive=self.recursive) class MountFailedError(Exception): pass class DecompressionError(Exception): pass def ExtendedTemporaryFile(**kwargs): fh = tempfile.NamedTemporaryFile(**kwargs) # Replace its unlink with a quiet version # that does not raise errors when the # file to unlink has been unlinked elsewhere.. LOG.debug("Created temporary file %s", fh.name) fh.unlink = del_file # Add a new method that will unlink # right 'now' but still lets the exit # method attempt to remove it (which will # not throw due to our del file being quiet # about files that are not there) def unlink_now(): fh.unlink(fh.name) setattr(fh, 'unlink_now', unlink_now) return fh def fork_cb(child_cb, *args, **kwargs): fid = os.fork() if fid == 0: try: child_cb(*args, **kwargs) os._exit(0) except Exception: logexc(LOG, "Failed forking and calling callback %s", type_utils.obj_name(child_cb)) os._exit(1) else: LOG.debug("Forked child %s who will run callback %s", fid, type_utils.obj_name(child_cb)) def is_true(val, addons=None): if isinstance(val, (bool)): return val is True check_set = TRUE_STRINGS if addons: check_set = list(check_set) + addons if six.text_type(val).lower().strip() in check_set: return True return False def is_false(val, addons=None): if isinstance(val, (bool)): return val is False check_set = FALSE_STRINGS if addons: check_set = list(check_set) + addons if six.text_type(val).lower().strip() in check_set: return True return False def translate_bool(val, addons=None): if not val: # This handles empty lists and false and # other things that python believes are false return False # If its already a boolean skip if isinstance(val, (bool)): return val return is_true(val, addons) def rand_str(strlen=32, select_from=None): if not select_from: select_from = string.ascii_letters + string.digits return "".join([random.choice(select_from) for _x in range(0, strlen)]) def read_conf(fname): try: return load_yaml(load_file(fname), default={}) except IOError as e: if e.errno == errno.ENOENT: return {} else: raise # Merges X lists, and then keeps the # unique ones, but orders by sort order # instead of by the original order def uniq_merge_sorted(*lists): return sorted(uniq_merge(*lists)) # Merges X lists and then iterates over those # and only keeps the unique items (order preserving) # and returns that merged and uniqued list as the # final result. # # Note: if any entry is a string it will be # split on commas and empty entries will be # evicted and merged in accordingly. def uniq_merge(*lists): combined_list = [] for a_list in lists: if isinstance(a_list, six.string_types): a_list = a_list.strip().split(",") # Kickout the empty ones a_list = [a for a in a_list if len(a)] combined_list.extend(a_list) return uniq_list(combined_list) def clean_filename(fn): for (k, v) in FN_REPLACEMENTS.items(): fn = fn.replace(k, v) removals = [] for k in fn: if k not in FN_ALLOWED: removals.append(k) for k in removals: fn = fn.replace(k, '') fn = fn.strip() return fn def decomp_gzip(data, quiet=True, decode=True): try: buf = six.BytesIO(encode_text(data)) with contextlib.closing(gzip.GzipFile(None, "rb", 1, buf)) as gh: if decode: return decode_binary(gh.read()) else: return gh.read() except Exception as e: if quiet: return data else: raise DecompressionError(six.text_type(e)) def extract_usergroup(ug_pair): if not ug_pair: return (None, None) ug_parted = ug_pair.split(':', 1) u = ug_parted[0].strip() if len(ug_parted) == 2: g = ug_parted[1].strip() else: g = None if not u or u == "-1" or u.lower() == "none": u = None if not g or g == "-1" or g.lower() == "none": g = None return (u, g) def find_modules(root_dir): entries = dict() for fname in glob.glob(os.path.join(root_dir, "*.py")): if not os.path.isfile(fname): continue modname = os.path.basename(fname)[0:-3] modname = modname.strip() if modname and modname.find(".") == -1: entries[fname] = modname return entries def multi_log(text, console=True, stderr=True, log=None, log_level=logging.DEBUG): if stderr: sys.stderr.write(text) if console: conpath = "/dev/console" if os.path.exists(conpath): with open(conpath, 'w') as wfh: wfh.write(text) wfh.flush() else: # A container may lack /dev/console (arguably a container bug). If # it does not exist, then write output to stdout. this will result # in duplicate stderr and stdout messages if stderr was True. # # even though upstart or systemd might have set up output to go to # /dev/console, the user may have configured elsewhere via # cloud-config 'output'. If there is /dev/console, messages will # still get there. sys.stdout.write(text) if log: if text[-1] == "\n": log.log(log_level, text[:-1]) else: log.log(log_level, text) def load_json(text, root_types=(dict,)): decoded = json.loads(decode_binary(text)) if not isinstance(decoded, tuple(root_types)): expected_types = ", ".join([str(t) for t in root_types]) raise TypeError("(%s) root types expected, got %s instead" % (expected_types, type(decoded))) return decoded def is_ipv4(instr): """determine if input string is a ipv4 address. return boolean.""" toks = instr.split('.') if len(toks) != 4: return False try: toks = [x for x in toks if int(x) < 256 and int(x) >= 0] except Exception: return False return len(toks) == 4 def get_cfg_option_bool(yobj, key, default=False): if key not in yobj: return default return translate_bool(yobj[key]) def get_cfg_option_str(yobj, key, default=None): if key not in yobj: return default val = yobj[key] if not isinstance(val, six.string_types): val = str(val) return val def get_cfg_option_int(yobj, key, default=0): return int(get_cfg_option_str(yobj, key, default=default)) def system_info(): return { 'platform': platform.platform(), 'release': platform.release(), 'python': platform.python_version(), 'uname': platform.uname(), 'dist': platform.linux_distribution(), } def get_cfg_option_list(yobj, key, default=None): """ Gets the C{key} config option from C{yobj} as a list of strings. If the key is present as a single string it will be returned as a list with one string arg. @param yobj: The configuration object. @param key: The configuration key to get. @param default: The default to return if key is not found. @return: The configuration option as a list of strings or default if key is not found. """ if key not in yobj: return default if yobj[key] is None: return [] val = yobj[key] if isinstance(val, (list)): cval = [v for v in val] return cval if not isinstance(val, six.string_types): val = str(val) return [val] # get a cfg entry by its path array # for f['a']['b']: get_cfg_by_path(mycfg,('a','b')) def get_cfg_by_path(yobj, keyp, default=None): cur = yobj for tok in keyp: if tok not in cur: return default cur = cur[tok] return cur def fixup_output(cfg, mode): (outfmt, errfmt) = get_output_cfg(cfg, mode) redirect_output(outfmt, errfmt) return (outfmt, errfmt) # redirect_output(outfmt, errfmt, orig_out, orig_err) # replace orig_out and orig_err with filehandles specified in outfmt or errfmt # fmt can be: # > FILEPATH # >> FILEPATH # | program [ arg1 [ arg2 [ ... ] ] ] # # with a '|', arguments are passed to shell, so one level of # shell escape is required. # # if _CLOUD_INIT_SAVE_STDOUT is set in environment to a non empty and true # value then output input will not be closed (useful for debugging). # def redirect_output(outfmt, errfmt, o_out=None, o_err=None): if is_true(os.environ.get("_CLOUD_INIT_SAVE_STDOUT")): LOG.debug("Not redirecting output due to _CLOUD_INIT_SAVE_STDOUT") return if not o_out: o_out = sys.stdout if not o_err: o_err = sys.stderr if outfmt: LOG.debug("Redirecting %s to %s", o_out, outfmt) (mode, arg) = outfmt.split(" ", 1) if mode == ">" or mode == ">>": owith = "ab" if mode == ">": owith = "wb" new_fp = open(arg, owith) elif mode == "|": proc = subprocess.Popen(arg, shell=True, stdin=subprocess.PIPE) new_fp = proc.stdin else: raise TypeError("Invalid type for output format: %s" % outfmt) if o_out: os.dup2(new_fp.fileno(), o_out.fileno()) if errfmt == outfmt: LOG.debug("Redirecting %s to %s", o_err, outfmt) os.dup2(new_fp.fileno(), o_err.fileno()) return if errfmt: LOG.debug("Redirecting %s to %s", o_err, errfmt) (mode, arg) = errfmt.split(" ", 1) if mode == ">" or mode == ">>": owith = "ab" if mode == ">": owith = "wb" new_fp = open(arg, owith) elif mode == "|": proc = subprocess.Popen(arg, shell=True, stdin=subprocess.PIPE) new_fp = proc.stdin else: raise TypeError("Invalid type for error format: %s" % errfmt) if o_err: os.dup2(new_fp.fileno(), o_err.fileno()) def make_url(scheme, host, port=None, path='', params='', query='', fragment=''): pieces = [] pieces.append(scheme or '') netloc = '' if host: netloc = str(host) if port is not None: netloc += ":" + "%s" % (port) pieces.append(netloc or '') pieces.append(path or '') pieces.append(params or '') pieces.append(query or '') pieces.append(fragment or '') return urlparse.urlunparse(pieces) def mergemanydict(srcs, reverse=False): if reverse: srcs = reversed(srcs) merged_cfg = {} for cfg in srcs: if cfg: # Figure out which mergers to apply... mergers_to_apply = mergers.dict_extract_mergers(cfg) if not mergers_to_apply: mergers_to_apply = mergers.default_mergers() merger = mergers.construct(mergers_to_apply) merged_cfg = merger.merge(merged_cfg, cfg) return merged_cfg @contextlib.contextmanager def chdir(ndir): curr = os.getcwd() try: os.chdir(ndir) yield ndir finally: os.chdir(curr) @contextlib.contextmanager def umask(n_msk): old = os.umask(n_msk) try: yield old finally: os.umask(old) @contextlib.contextmanager def tempdir(**kwargs): # This seems like it was only added in python 3.2 # Make it since its useful... # See: http://bugs.python.org/file12970/tempdir.patch tdir = tempfile.mkdtemp(**kwargs) try: yield tdir finally: del_dir(tdir) def center(text, fill, max_len): return '{0:{fill}{align}{size}}'.format(text, fill=fill, align="^", size=max_len) def del_dir(path): LOG.debug("Recursively deleting %s", path) shutil.rmtree(path) def runparts(dirp, skip_no_exist=True, exe_prefix=None): if skip_no_exist and not os.path.isdir(dirp): return failed = [] attempted = [] if exe_prefix is None: prefix = [] elif isinstance(exe_prefix, str): prefix = [str(exe_prefix)] elif isinstance(exe_prefix, list): prefix = exe_prefix else: raise TypeError("exe_prefix must be None, str, or list") for exe_name in sorted(os.listdir(dirp)): exe_path = os.path.join(dirp, exe_name) if os.path.isfile(exe_path) and os.access(exe_path, os.X_OK): attempted.append(exe_path) try: subp(prefix + [exe_path], capture=False) except ProcessExecutionError as e: logexc(LOG, "Failed running %s [%s]", exe_path, e.exit_code) failed.append(e) if failed and attempted: raise RuntimeError('Runparts: %s failures in %s attempted commands' % (len(failed), len(attempted))) # read_optional_seed # returns boolean indicating success or failure (presense of files) # if files are present, populates 'fill' dictionary with 'user-data' and # 'meta-data' entries def read_optional_seed(fill, base="", ext="", timeout=5): try: (md, ud) = read_seeded(base, ext, timeout) fill['user-data'] = ud fill['meta-data'] = md return True except url_helper.UrlError as e: if e.code == url_helper.NOT_FOUND: return False raise def fetch_ssl_details(paths=None): ssl_details = {} # Lookup in these locations for ssl key/cert files ssl_cert_paths = [ '/var/lib/cloud/data/ssl', '/var/lib/cloud/instance/data/ssl', ] if paths: ssl_cert_paths.extend([ os.path.join(paths.get_ipath_cur('data'), 'ssl'), os.path.join(paths.get_cpath('data'), 'ssl'), ]) ssl_cert_paths = uniq_merge(ssl_cert_paths) ssl_cert_paths = [d for d in ssl_cert_paths if d and os.path.isdir(d)] cert_file = None for d in ssl_cert_paths: if os.path.isfile(os.path.join(d, 'cert.pem')): cert_file = os.path.join(d, 'cert.pem') break key_file = None for d in ssl_cert_paths: if os.path.isfile(os.path.join(d, 'key.pem')): key_file = os.path.join(d, 'key.pem') break if cert_file and key_file: ssl_details['cert_file'] = cert_file ssl_details['key_file'] = key_file elif cert_file: ssl_details['cert_file'] = cert_file return ssl_details def read_file_or_url(url, timeout=5, retries=10, headers=None, data=None, sec_between=1, ssl_details=None, headers_cb=None, exception_cb=None): url = url.lstrip() if url.startswith("/"): url = "file://%s" % url if url.lower().startswith("file://"): if data: LOG.warn("Unable to post data to file resource %s", url) file_path = url[len("file://"):] try: contents = load_file(file_path, decode=False) except IOError as e: code = e.errno if e.errno == errno.ENOENT: code = url_helper.NOT_FOUND raise url_helper.UrlError(cause=e, code=code, headers=None, url=url) return url_helper.FileResponse(file_path, contents=contents) else: return url_helper.readurl(url, timeout=timeout, retries=retries, headers=headers, headers_cb=headers_cb, data=data, sec_between=sec_between, ssl_details=ssl_details, exception_cb=exception_cb) def load_yaml(blob, default=None, allowed=(dict,)): loaded = default blob = decode_binary(blob) try: LOG.debug("Attempting to load yaml from string " "of length %s with allowed root types %s", len(blob), allowed) converted = safeyaml.load(blob) if not isinstance(converted, allowed): # Yes this will just be caught, but thats ok for now... raise TypeError(("Yaml load allows %s root types," " but got %s instead") % (allowed, type_utils.obj_name(converted))) loaded = converted except (yaml.YAMLError, TypeError, ValueError): if len(blob) == 0: LOG.debug("load_yaml given empty string, returning default") else: logexc(LOG, "Failed loading yaml blob") return loaded def read_seeded(base="", ext="", timeout=5, retries=10, file_retries=0): if base.startswith("/"): base = "file://%s" % base # default retries for file is 0. for network is 10 if base.startswith("file://"): retries = file_retries if base.find("%s") >= 0: ud_url = base % ("user-data" + ext) md_url = base % ("meta-data" + ext) else: ud_url = "%s%s%s" % (base, "user-data", ext) md_url = "%s%s%s" % (base, "meta-data", ext) md_resp = read_file_or_url(md_url, timeout, retries, file_retries) md = None if md_resp.ok(): md = load_yaml(decode_binary(md_resp.contents), default={}) ud_resp = read_file_or_url(ud_url, timeout, retries, file_retries) ud = None if ud_resp.ok(): ud = ud_resp.contents return (md, ud) def read_conf_d(confd): # Get reverse sorted list (later trumps newer) confs = sorted(os.listdir(confd), reverse=True) # Remove anything not ending in '.cfg' confs = [f for f in confs if f.endswith(".cfg")] # Remove anything not a file confs = [f for f in confs if os.path.isfile(os.path.join(confd, f))] # Load them all so that they can be merged cfgs = [] for fn in confs: cfgs.append(read_conf(os.path.join(confd, fn))) return mergemanydict(cfgs) def read_conf_with_confd(cfgfile): cfg = read_conf(cfgfile) confd = False if "conf_d" in cfg: confd = cfg['conf_d'] if confd: if not isinstance(confd, six.string_types): raise TypeError(("Config file %s contains 'conf_d' " "with non-string type %s") % (cfgfile, type_utils.obj_name(confd))) else: confd = str(confd).strip() elif os.path.isdir("%s.d" % cfgfile): confd = "%s.d" % cfgfile if not confd or not os.path.isdir(confd): return cfg # Conf.d settings override input configuration confd_cfg = read_conf_d(confd) return mergemanydict([confd_cfg, cfg]) def read_cc_from_cmdline(cmdline=None): # this should support reading cloud-config information from # the kernel command line. It is intended to support content of the # format: # cc: [end_cc] # this would include: # cc: ssh_import_id: [smoser, kirkland]\\n # cc: ssh_import_id: [smoser, bob]\\nruncmd: [ [ ls, -l ], echo hi ] end_cc # cc:ssh_import_id: [smoser] end_cc cc:runcmd: [ [ ls, -l ] ] end_cc if cmdline is None: cmdline = get_cmdline() tag_begin = "cc:" tag_end = "end_cc" begin_l = len(tag_begin) end_l = len(tag_end) clen = len(cmdline) tokens = [] begin = cmdline.find(tag_begin) while begin >= 0: end = cmdline.find(tag_end, begin + begin_l) if end < 0: end = clen tokens.append(cmdline[begin + begin_l:end].lstrip().replace("\\n", "\n")) begin = cmdline.find(tag_begin, end + end_l) return '\n'.join(tokens) def dos2unix(contents): # find first end of line pos = contents.find('\n') if pos <= 0 or contents[pos - 1] != '\r': return contents return contents.replace('\r\n', '\n') def get_hostname_fqdn(cfg, cloud): # return the hostname and fqdn from 'cfg'. If not found in cfg, # then fall back to data from cloud if "fqdn" in cfg: # user specified a fqdn. Default hostname then is based off that fqdn = cfg['fqdn'] hostname = get_cfg_option_str(cfg, "hostname", fqdn.split('.')[0]) else: if "hostname" in cfg and cfg['hostname'].find('.') > 0: # user specified hostname, and it had '.' in it # be nice to them. set fqdn and hostname from that fqdn = cfg['hostname'] hostname = cfg['hostname'][:fqdn.find('.')] else: # no fqdn set, get fqdn from cloud. # get hostname from cfg if available otherwise cloud fqdn = cloud.get_hostname(fqdn=True) if "hostname" in cfg: hostname = cfg['hostname'] else: hostname = cloud.get_hostname() return (hostname, fqdn) def get_fqdn_from_hosts(hostname, filename="/etc/hosts"): """ For each host a single line should be present with the following information: IP_address canonical_hostname [aliases...] Fields of the entry are separated by any number of blanks and/or tab characters. Text from a "#" character until the end of the line is a comment, and is ignored. Host names may contain only alphanumeric characters, minus signs ("-"), and periods ("."). They must begin with an alphabetic character and end with an alphanumeric character. Optional aliases provide for name changes, alternate spellings, shorter hostnames, or generic hostnames (for example, localhost). """ fqdn = None try: for line in load_file(filename).splitlines(): hashpos = line.find("#") if hashpos >= 0: line = line[0:hashpos] line = line.strip() if not line: continue # If there there is less than 3 entries # (IP_address, canonical_hostname, alias) # then ignore this line toks = line.split() if len(toks) < 3: continue if hostname in toks[2:]: fqdn = toks[1] break except IOError: pass return fqdn def get_cmdline_url(names=('cloud-config-url', 'url'), starts=b"#cloud-config", cmdline=None): if cmdline is None: cmdline = get_cmdline() data = keyval_str_to_dict(cmdline) url = None key = None for key in names: if key in data: url = data[key] break if not url: return (None, None, None) resp = read_file_or_url(url) # allow callers to pass starts as text when comparing to bytes contents starts = encode_text(starts) if resp.ok() and resp.contents.startswith(starts): return (key, url, resp.contents) return (key, url, None) def is_resolvable(name): """determine if a url is resolvable, return a boolean This also attempts to be resilent against dns redirection. Note, that normal nsswitch resolution is used here. So in order to avoid any utilization of 'search' entries in /etc/resolv.conf we have to append '.'. The top level 'invalid' domain is invalid per RFC. And example.com should also not exist. The random entry will be resolved inside the search list. """ global _DNS_REDIRECT_IP if _DNS_REDIRECT_IP is None: badips = set() badnames = ("does-not-exist.example.com.", "example.invalid.", rand_str()) badresults = {} for iname in badnames: try: result = socket.getaddrinfo(iname, None, 0, 0, socket.SOCK_STREAM, socket.AI_CANONNAME) badresults[iname] = [] for (_fam, _stype, _proto, cname, sockaddr) in result: badresults[iname].append("%s: %s" % (cname, sockaddr[0])) badips.add(sockaddr[0]) except (socket.gaierror, socket.error): pass _DNS_REDIRECT_IP = badips if badresults: LOG.debug("detected dns redirection: %s", badresults) try: result = socket.getaddrinfo(name, None) # check first result's sockaddr field addr = result[0][4][0] if addr in _DNS_REDIRECT_IP: return False return True except (socket.gaierror, socket.error): return False def get_hostname(): hostname = socket.gethostname() return hostname def gethostbyaddr(ip): try: return socket.gethostbyaddr(ip)[0] except socket.herror: return None def is_resolvable_url(url): """determine if this url is resolvable (existing or ip).""" return is_resolvable(urlparse.urlparse(url).hostname) def search_for_mirror(candidates): """ Search through a list of mirror urls for one that works This needs to return quickly. """ for cand in candidates: try: if is_resolvable_url(cand): return cand except Exception: pass return None def close_stdin(): """ reopen stdin as /dev/null so even subprocesses or other os level things get /dev/null as input. if _CLOUD_INIT_SAVE_STDIN is set in environment to a non empty and true value then input will not be closed (useful for debugging). """ if is_true(os.environ.get("_CLOUD_INIT_SAVE_STDIN")): return with open(os.devnull) as fp: os.dup2(fp.fileno(), sys.stdin.fileno()) def find_devs_with(criteria=None, oformat='device', tag=None, no_cache=False, path=None): """ find devices matching given criteria (via blkid) criteria can be *one* of: TYPE= LABEL=