diff options
Diffstat (limited to 'cloudinit/net/dhcp.py')
| -rw-r--r-- | cloudinit/net/dhcp.py | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/cloudinit/net/dhcp.py b/cloudinit/net/dhcp.py index c98a97cd..17379918 100644 --- a/cloudinit/net/dhcp.py +++ b/cloudinit/net/dhcp.py @@ -92,10 +92,14 @@ class EphemeralDHCPv4(object): nmap = {'interface': 'interface', 'ip': 'fixed-address', 'prefix_or_mask': 'subnet-mask', 'broadcast': 'broadcast-address', + 'static_routes': 'rfc3442-classless-static-routes', 'router': 'routers'} kwargs = dict([(k, self.lease.get(v)) for k, v in nmap.items()]) if not kwargs['broadcast']: kwargs['broadcast'] = bcip(kwargs['prefix_or_mask'], kwargs['ip']) + if kwargs['static_routes']: + kwargs['static_routes'] = ( + parse_static_routes(kwargs['static_routes'])) if self.connectivity_url: kwargs['connectivity_url'] = self.connectivity_url ephipv4 = EphemeralIPv4Network(**kwargs) @@ -272,4 +276,90 @@ def networkd_get_option_from_leases(keyname, leases_d=None): return data[keyname] return None + +def parse_static_routes(rfc3442): + """ parse rfc3442 format and return a list containing tuple of strings. + + The tuple is composed of the network_address (including net length) and + gateway for a parsed static route. + + @param rfc3442: string in rfc3442 format + @returns: list of tuple(str, str) for all valid parsed routes until the + first parsing error. + + E.g. + sr = parse_state_routes("32,169,254,169,254,130,56,248,255,0,130,56,240,1") + sr = [ + ("169.254.169.254/32", "130.56.248.255"), ("0.0.0.0/0", "130.56.240.1") + ] + + Python version of isc-dhclient's hooks: + /etc/dhcp/dhclient-exit-hooks.d/rfc3442-classless-routes + """ + # raw strings from dhcp lease may end in semi-colon + rfc3442 = rfc3442.rstrip(";") + tokens = rfc3442.split(',') + static_routes = [] + + def _trunc_error(cidr, required, remain): + msg = ("RFC3442 string malformed. Current route has CIDR of %s " + "and requires %s significant octets, but only %s remain. " + "Verify DHCP rfc3442-classless-static-routes value: %s" + % (cidr, required, remain, rfc3442)) + LOG.error(msg) + + current_idx = 0 + for idx, tok in enumerate(tokens): + if idx < current_idx: + continue + net_length = int(tok) + if net_length in range(25, 33): + req_toks = 9 + if len(tokens[idx:]) < req_toks: + _trunc_error(net_length, req_toks, len(tokens[idx:])) + return static_routes + net_address = ".".join(tokens[idx+1:idx+5]) + gateway = ".".join(tokens[idx+5:idx+req_toks]) + current_idx = idx + req_toks + elif net_length in range(17, 25): + req_toks = 8 + if len(tokens[idx:]) < req_toks: + _trunc_error(net_length, req_toks, len(tokens[idx:])) + return static_routes + net_address = ".".join(tokens[idx+1:idx+4] + ["0"]) + gateway = ".".join(tokens[idx+4:idx+req_toks]) + current_idx = idx + req_toks + elif net_length in range(9, 17): + req_toks = 7 + if len(tokens[idx:]) < req_toks: + _trunc_error(net_length, req_toks, len(tokens[idx:])) + return static_routes + net_address = ".".join(tokens[idx+1:idx+3] + ["0", "0"]) + gateway = ".".join(tokens[idx+3:idx+req_toks]) + current_idx = idx + req_toks + elif net_length in range(1, 9): + req_toks = 6 + if len(tokens[idx:]) < req_toks: + _trunc_error(net_length, req_toks, len(tokens[idx:])) + return static_routes + net_address = ".".join(tokens[idx+1:idx+2] + ["0", "0", "0"]) + gateway = ".".join(tokens[idx+2:idx+req_toks]) + current_idx = idx + req_toks + elif net_length == 0: + req_toks = 5 + if len(tokens[idx:]) < req_toks: + _trunc_error(net_length, req_toks, len(tokens[idx:])) + return static_routes + net_address = "0.0.0.0" + gateway = ".".join(tokens[idx+1:idx+req_toks]) + current_idx = idx + req_toks + else: + LOG.error('Parsed invalid net length "%s". Verify DHCP ' + 'rfc3442-classless-static-routes value.', net_length) + return static_routes + + static_routes.append(("%s/%s" % (net_address, net_length), gateway)) + + return static_routes + # vi: ts=4 expandtab |