From d00da2d5b0d45db5670622a66d833d2abb907388 Mon Sep 17 00:00:00 2001 From: Scott Moser Date: Wed, 24 May 2017 21:10:50 -0400 Subject: net: normalize data in network_state object The network_state object's network and route keys would have different information depending upon how the network_state object was populated. This change cleans that up. Now: * address will always contain an IP address. * prefix will always include an integer value that is the network_prefix for the address. * netmask will be present only if the address is ipv4, and its value will always correlate to the 'prefix'. --- cloudinit/net/network_state.py | 244 ++++++++++++++++++++++++++++++++--------- 1 file changed, 194 insertions(+), 50 deletions(-) (limited to 'cloudinit/net/network_state.py') diff --git a/cloudinit/net/network_state.py b/cloudinit/net/network_state.py index 9e9c05a0..87a7222d 100644 --- a/cloudinit/net/network_state.py +++ b/cloudinit/net/network_state.py @@ -289,19 +289,15 @@ class NetworkStateInterpreter(object): iface.update({param: val}) # convert subnet ipv6 netmask to cidr as needed - subnets = command.get('subnets') - if subnets: + subnets = _normalize_subnets(command.get('subnets')) + + # automatically set 'use_ipv6' if any addresses are ipv6 + if not self.use_ipv6: for subnet in subnets: - if subnet['type'] == 'static': - if ':' in subnet['address']: - self.use_ipv6 = True - if 'netmask' in subnet and ':' in subnet['address']: - subnet['netmask'] = mask2cidr(subnet['netmask']) - for route in subnet.get('routes', []): - if 'netmask' in route: - route['netmask'] = mask2cidr(route['netmask']) - elif subnet['type'].endswith('6'): + if (subnet.get('type').endswith('6') or + is_ipv6_addr(subnet.get('address'))): self.use_ipv6 = True + break iface.update({ 'name': command.get('name'), @@ -456,16 +452,7 @@ class NetworkStateInterpreter(object): @ensure_command_keys(['destination']) def handle_route(self, command): - routes = self._network_state.get('routes', []) - network, cidr = command['destination'].split("/") - netmask = cidr2mask(int(cidr)) - route = { - 'network': network, - 'netmask': netmask, - 'gateway': command.get('gateway'), - 'metric': command.get('metric'), - } - routes.append(route) + self._network_state['routes'].append(_normalize_route(command)) # V2 handlers def handle_bonds(self, command): @@ -666,18 +653,9 @@ class NetworkStateInterpreter(object): routes = [] for route in cfg.get('routes', []): - route_addr = route.get('to') - if "/" in route_addr: - route_addr, route_cidr = route_addr.split("/") - route_netmask = cidr2mask(route_cidr) - subnet_route = { - 'address': route_addr, - 'netmask': route_netmask, - 'gateway': route.get('via') - } - routes.append(subnet_route) - if len(routes) > 0: - subnet.update({'routes': routes}) + routes.append(_normalize_route( + {'address': route.get('to'), 'gateway': route.get('via')})) + subnet['routes'] = routes if ":" in address: if 'gateway6' in cfg and gateway6 is None: @@ -692,53 +670,219 @@ class NetworkStateInterpreter(object): return subnets +def _normalize_subnet(subnet): + # Prune all keys with None values. + subnet = copy.deepcopy(subnet) + normal_subnet = dict((k, v) for k, v in subnet.items() if v) + + if subnet.get('type') in ('static', 'static6'): + normal_subnet.update( + _normalize_net_keys(normal_subnet, address_keys=('address',))) + normal_subnet['routes'] = [_normalize_route(r) + for r in subnet.get('routes', [])] + return normal_subnet + + +def _normalize_net_keys(network, address_keys=()): + """Normalize dictionary network keys returning prefix and address keys. + + @param network: A dict of network-related definition containing prefix, + netmask and address_keys. + @param address_keys: A tuple of keys to search for representing the address + or cidr. The first address_key discovered will be used for + normalization. + + @returns: A dict containing normalized prefix and matching addr_key. + """ + net = dict((k, v) for k, v in network.items() if v) + addr_key = None + for key in address_keys: + if net.get(key): + addr_key = key + break + if not addr_key: + message = ( + 'No config network address keys [%s] found in %s' % + (','.join(address_keys), network)) + LOG.error(message) + raise ValueError(message) + + addr = net.get(addr_key) + ipv6 = is_ipv6_addr(addr) + netmask = net.get('netmask') + if "/" in addr: + addr_part, _, maybe_prefix = addr.partition("/") + net[addr_key] = addr_part + try: + prefix = int(maybe_prefix) + except ValueError: + # this supports input of
/255.255.255.0 + prefix = mask_to_net_prefix(maybe_prefix) + elif netmask: + prefix = mask_to_net_prefix(netmask) + elif 'prefix' in net: + prefix = int(prefix) + else: + prefix = 64 if ipv6 else 24 + + if 'prefix' in net and str(net['prefix']) != str(prefix): + LOG.warning("Overwriting existing 'prefix' with '%s' in " + "network info: %s", prefix, net) + net['prefix'] = prefix + + if ipv6: + # TODO: we could/maybe should add this back with the very uncommon + # 'netmask' for ipv6. We need a 'net_prefix_to_ipv6_mask' for that. + if 'netmask' in net: + del net['netmask'] + else: + net['netmask'] = net_prefix_to_ipv4_mask(net['prefix']) + + return net + + +def _normalize_route(route): + """normalize a route. + return a dictionary with only: + 'type': 'route' (only present if it was present in input) + 'network': the network portion of the route as a string. + 'prefix': the network prefix for address as an integer. + 'metric': integer metric (only if present in input). + 'netmask': netmask (string) equivalent to prefix iff network is ipv4. + """ + # Prune None-value keys. Specifically allow 0 (a valid metric). + normal_route = dict((k, v) for k, v in route.items() + if v not in ("", None)) + if 'destination' in normal_route: + normal_route['network'] = normal_route['destination'] + del normal_route['destination'] + + normal_route.update( + _normalize_net_keys( + normal_route, address_keys=('network', 'destination'))) + + metric = normal_route.get('metric') + if metric: + try: + normal_route['metric'] = int(metric) + except ValueError: + raise TypeError( + 'Route config metric {} is not an integer'.format(metric)) + return normal_route + + +def _normalize_subnets(subnets): + if not subnets: + subnets = [] + return [_normalize_subnet(s) for s in subnets] + + +def is_ipv6_addr(address): + if not address: + return False + return ":" in str(address) + + def subnet_is_ipv6(subnet): """Common helper for checking network_state subnets for ipv6.""" # 'static6' or 'dhcp6' if subnet['type'].endswith('6'): # This is a request for DHCPv6. return True - elif subnet['type'] == 'static' and ":" in subnet['address']: + elif subnet['type'] == 'static' and is_ipv6_addr(subnet.get('address')): return True return False -def cidr2mask(cidr): +def net_prefix_to_ipv4_mask(prefix): + """Convert a network prefix to an ipv4 netmask. + + This is the inverse of ipv4_mask_to_net_prefix. + 24 -> "255.255.255.0" + Also supports input as a string.""" + mask = [0, 0, 0, 0] - for i in list(range(0, cidr)): + for i in list(range(0, int(prefix))): idx = int(i / 8) mask[idx] = mask[idx] + (1 << (7 - i % 8)) return ".".join([str(x) for x in mask]) -def ipv4mask2cidr(mask): - if '.' not in mask: +def ipv4_mask_to_net_prefix(mask): + """Convert an ipv4 netmask into a network prefix length. + + If the input is already an integer or a string representation of + an integer, then int(mask) will be returned. + "255.255.255.0" => 24 + str(24) => 24 + "24" => 24 + """ + if isinstance(mask, int): return mask - return sum([bin(int(x)).count('1') for x in mask.split('.')]) + if isinstance(mask, six.string_types): + try: + return int(mask) + except ValueError: + pass + else: + raise TypeError("mask '%s' is not a string or int") + if '.' not in mask: + raise ValueError("netmask '%s' does not contain a '.'" % mask) -def ipv6mask2cidr(mask): - if ':' not in mask: + toks = mask.split(".") + if len(toks) != 4: + raise ValueError("netmask '%s' had only %d parts" % (mask, len(toks))) + + return sum([bin(int(x)).count('1') for x in toks]) + + +def ipv6_mask_to_net_prefix(mask): + """Convert an ipv6 netmask (very uncommon) or prefix (64) to prefix. + + If 'mask' is an integer or string representation of one then + int(mask) will be returned. + """ + + if isinstance(mask, int): return mask + if isinstance(mask, six.string_types): + try: + return int(mask) + except ValueError: + pass + else: + raise TypeError("mask '%s' is not a string or int") + + if ':' not in mask: + raise ValueError("mask '%s' does not have a ':'") bitCount = [0, 0x8000, 0xc000, 0xe000, 0xf000, 0xf800, 0xfc00, 0xfe00, 0xff00, 0xff80, 0xffc0, 0xffe0, 0xfff0, 0xfff8, 0xfffc, 0xfffe, 0xffff] - cidr = 0 + prefix = 0 for word in mask.split(':'): if not word or int(word, 16) == 0: break - cidr += bitCount.index(int(word, 16)) + prefix += bitCount.index(int(word, 16)) + + return prefix - return cidr +def mask_to_net_prefix(mask): + """Return the network prefix for the netmask provided. -def mask2cidr(mask): - if ':' in str(mask): - return ipv6mask2cidr(mask) - elif '.' in str(mask): - return ipv4mask2cidr(mask) + Supports ipv4 or ipv6 netmasks.""" + try: + # if 'mask' is a prefix that is an integer. + # then just return it. + return int(mask) + except ValueError: + pass + if is_ipv6_addr(mask): + return ipv6_mask_to_net_prefix(mask) else: - return mask + return ipv4_mask_to_net_prefix(mask) + # vi: ts=4 expandtab -- cgit v1.2.3