# Copyright (C) 2013-2014 Canonical Ltd. # # Author: Scott Moser # Author: Blake Rouse # # This file is part of cloud-init. See LICENSE file for license information. import abc import base64 import glob import gzip import io import os from cloudinit import util from . import get_devicelist from . import read_sys_net_safe _OPEN_ISCSI_INTERFACE_FILE = "/run/initramfs/open-iscsi.interface" class InitramfsNetworkConfigSource(metaclass=abc.ABCMeta): """ABC for net config sources that read config written by initramfses""" @abc.abstractmethod def is_applicable(self): # type: () -> bool """Is this initramfs config source applicable to the current system?""" pass @abc.abstractmethod def render_config(self): # type: () -> dict """Render a v1 network config from the initramfs configuration""" pass class KlibcNetworkConfigSource(InitramfsNetworkConfigSource): """InitramfsNetworkConfigSource for klibc initramfs (i.e. Debian/Ubuntu) Has three parameters, but they are intended to make testing simpler, _not_ for use in production code. (This is indicated by the prepended underscores.) """ def __init__(self, _files=None, _mac_addrs=None, _cmdline=None): self._files = _files self._mac_addrs = _mac_addrs self._cmdline = _cmdline # Set defaults here, as they require computation that we don't want to # do at method definition time if self._files is None: self._files = _get_klibc_net_cfg_files() if self._cmdline is None: self._cmdline = util.get_cmdline() if self._mac_addrs is None: self._mac_addrs = {} for k in get_devicelist(): mac_addr = read_sys_net_safe(k, 'address') if mac_addr: self._mac_addrs[k] = mac_addr def is_applicable(self): # type: () -> bool """ Return whether this system has klibc initramfs network config or not Will return True if: (a) klibc files exist in /run, AND (b) either: (i) ip= or ip6= are on the kernel cmdline, OR (ii) an open-iscsi interface file is present in the system """ if self._files: if 'ip=' in self._cmdline or 'ip6=' in self._cmdline: return True if os.path.exists(_OPEN_ISCSI_INTERFACE_FILE): # iBft can configure networking without ip= return True return False def render_config(self): # type: () -> dict return config_from_klibc_net_cfg( files=self._files, mac_addrs=self._mac_addrs, ) _INITRAMFS_CONFIG_SOURCES = [KlibcNetworkConfigSource] def _klibc_to_config_entry(content, mac_addrs=None): """Convert a klibc written shell content file to a 'config' entry When ip= is seen on the kernel command line in debian initramfs and networking is brought up, ipconfig will populate /run/net-.cfg. The files are shell style syntax, and examples are in the tests provided here. There is no good documentation on this unfortunately. DEVICE= is expected/required and PROTO should indicate if this is 'static' or 'dhcp' or 'dhcp6' (LP: #1621507). note that IPV6PROTO is also written by newer code to address the possibility of both ipv4 and ipv6 getting addresses. """ if mac_addrs is None: mac_addrs = {} data = util.load_shell_content(content) try: name = data['DEVICE'] if 'DEVICE' in data else data['DEVICE6'] except KeyError: raise ValueError("no 'DEVICE' or 'DEVICE6' entry in data") # ipconfig on precise does not write PROTO # IPv6 config gives us IPV6PROTO, not PROTO. proto = data.get('PROTO', data.get('IPV6PROTO')) if not proto: if data.get('filename'): proto = 'dhcp' else: proto = 'static' if proto not in ('static', 'dhcp', 'dhcp6'): raise ValueError("Unexpected value for PROTO: %s" % proto) iface = { 'type': 'physical', 'name': name, 'subnets': [], } if name in mac_addrs: iface['mac_address'] = mac_addrs[name] # Handle both IPv4 and IPv6 values for pre in ('IPV4', 'IPV6'): # if no IPV4ADDR or IPV6ADDR, then go on. if pre + "ADDR" not in data: continue # PROTO for ipv4, IPV6PROTO for ipv6 cur_proto = data.get(pre + 'PROTO', proto) subnet = {'type': cur_proto, 'control': 'manual'} # only populate address for static types. While the rendered config # may have an address for dhcp, that is not really expected. if cur_proto == 'static': subnet['address'] = data[pre + 'ADDR'] # these fields go right on the subnet for key in ('NETMASK', 'BROADCAST', 'GATEWAY'): if pre + key in data: subnet[key.lower()] = data[pre + key] dns = [] # handle IPV4DNS0 or IPV6DNS0 for nskey in ('DNS0', 'DNS1'): ns = data.get(pre + nskey) # verify it has something other than 0.0.0.0 (or ipv6) if ns and len(ns.strip(":.0")): dns.append(data[pre + nskey]) if dns: subnet['dns_nameservers'] = dns # add search to both ipv4 and ipv6, as it has no namespace search = data.get('DOMAINSEARCH') if search: if ',' in search: subnet['dns_search'] = search.split(",") else: subnet['dns_search'] = search.split() iface['subnets'].append(subnet) return name, iface def _get_klibc_net_cfg_files(): return glob.glob('/run/net-*.conf') + glob.glob('/run/net6-*.conf') def config_from_klibc_net_cfg(files=None, mac_addrs=None): if files is None: files = _get_klibc_net_cfg_files() entries = [] names = {} for cfg_file in files: name, entry = _klibc_to_config_entry(util.load_file(cfg_file), mac_addrs=mac_addrs) if name in names: prev = names[name]['entry'] if prev.get('mac_address') != entry.get('mac_address'): raise ValueError( "device '{name}' was defined multiple times ({files})" " but had differing mac addresses: {old} -> {new}.".format( name=name, files=' '.join(names[name]['files']), old=prev.get('mac_address'), new=entry.get('mac_address'))) prev['subnets'].extend(entry['subnets']) names[name]['files'].append(cfg_file) else: names[name] = {'files': [cfg_file], 'entry': entry} entries.append(entry) return {'config': entries, 'version': 1} def read_initramfs_config(): """ Return v1 network config for initramfs-configured networking (or None) This will consider each _INITRAMFS_CONFIG_SOURCES entry in turn, and return v1 network configuration for the first one that is applicable. If none are applicable, return None. """ for src_cls in _INITRAMFS_CONFIG_SOURCES: cfg_source = src_cls() if not cfg_source.is_applicable(): continue return cfg_source.render_config() return None def _decomp_gzip(blob, strict=True): # decompress blob. raise exception if not compressed unless strict=False. with io.BytesIO(blob) as iobuf: gzfp = None try: gzfp = gzip.GzipFile(mode="rb", fileobj=iobuf) return gzfp.read() except IOError: if strict: raise return blob finally: if gzfp: gzfp.close() def _b64dgz(b64str, gzipped="try"): # decode a base64 string. If gzipped is true, transparently uncompresss # if gzipped is 'try', then try gunzip, returning the original on fail. try: blob = base64.b64decode(b64str) except TypeError: raise ValueError("Invalid base64 text: %s" % b64str) if not gzipped: return blob return _decomp_gzip(blob, strict=gzipped != "try") def read_kernel_cmdline_config(cmdline=None): if cmdline is None: cmdline = util.get_cmdline() if 'network-config=' in cmdline: data64 = None for tok in cmdline.split(): if tok.startswith("network-config="): data64 = tok.split("=", 1)[1] if data64: return util.load_yaml(_b64dgz(data64)) return None # vi: ts=4 expandtab