From 8a5c00e897a98e8a532a364b1178bd3317bffef9 Mon Sep 17 00:00:00 2001 From: Christian Poessinger Date: Fri, 31 Aug 2018 22:32:22 +0200 Subject: T811: dhcpv6_server.py: add missing validators when comitting config changes --- src/conf_mode/dhcpv6_server.py | 91 ++++++++++++++++++++++++++++++++++++++---- 1 file changed, 84 insertions(+), 7 deletions(-) (limited to 'src/conf_mode/dhcpv6_server.py') diff --git a/src/conf_mode/dhcpv6_server.py b/src/conf_mode/dhcpv6_server.py index 260ccf395..bb3e6e90d 100755 --- a/src/conf_mode/dhcpv6_server.py +++ b/src/conf_mode/dhcpv6_server.py @@ -18,9 +18,12 @@ import sys import os +import ipaddress import jinja2 +import vyos.validate + from vyos.config import Config from vyos import ConfigError @@ -46,7 +49,7 @@ option dhcp6.preference {{ preference }}; shared-network {{ network.name }} { {%- for subnet in network.subnet %} subnet6 {{ subnet.network }} { - {%- for range in subnet.range6_temporary %} + {%- for range in subnet.range6_prefix %} range6 {{ range.prefix }}{{ " temporary" if range.temporary }}; {%- endfor %} {%- for range in subnet.range6 %} @@ -159,7 +162,7 @@ def get_config(): conf.set_level('service dhcpv6-server shared-network-name {0} subnet {1}'.format(network, net)) subnet = { 'network': net, - 'range6_temporary': [], + 'range6_prefix': [], 'range6': [], 'default_router': '', 'dns_server': [], @@ -194,7 +197,7 @@ def get_config(): range['temporary'] = True # Append to subnet temporary range6 list - subnet['range6_temporary'].append(range) + subnet['range6_prefix'].append(range) if conf.exists('address-range start'): for range in conf.list_nodes('address-range start'): @@ -249,11 +252,9 @@ def get_config(): if conf.exists('nisplus-server'): subnet['nisp_server'] = conf.return_values('nisplus-server') - # # Prefix Delegation (RFC 3633) - # if conf.exists('prefix-delegation'): - print("TODO") + print('TODO: This option is actually not implemented right now!') # Local SIP server that is to be used for all outbound SIP requests - IPv6 address if conf.exists('sip-server-address'): @@ -317,12 +318,88 @@ def verify(dhcpv6): raise ConfigError('No DHCPv6 shared networks configured.\n' \ 'At least one DHCPv6 shared network must be configured.') - # A shared-network requires a subnet definition + # Inspect shared-network/subnet + subnets = [] + listen_ok = False + for network in dhcpv6['shared_network']: + # A shared-network requires a subnet definition if len(network['subnet']) == 0: raise ConfigError('No DHCPv6 lease subnets configured for {0}. At least one\n' \ 'lease subnet must be configured for each shared network.'.format(network['name'])) + range6_start = [] + range6_stop = [] + for subnet in network['subnet']: + # Ususal range declaration with a start and stop address + for range6 in subnet['range6']: + # shorten names + start = range6['start'] + stop = range6['stop'] + + # DHCPv6 stop address is required + if start and not stop: + raise ConfigError('DHCPv6 range stop address for start {0} is not defined!'.format(start)) + + # Start address must be inside network + if not ipaddress.ip_address(start) in ipaddress.ip_network(subnet['network']): + raise ConfigError('DHCPv6 range start address {0} is not in subnet {1}\n' \ + 'specified for shared network {2}!'.format(start, subnet['network'], network['name'])) + + # Stop address must be inside network + if not ipaddress.ip_address(stop) in ipaddress.ip_network(subnet['network']): + raise ConfigError('DHCPv6 range stop address {0} is not in subnet {1}\n' \ + 'specified for shared network {2}!'.format(stop, subnet['network'], network['name'])) + + # Stop address must be greater or equal to start address + if not ipaddress.ip_address(stop) >= ipaddress.ip_address(start): + raise ConfigError('DHCPv6 range stop address {0} must be greater or equal\n' \ + 'to the range start address {1}!'.format(stop, start)) + + # DHCPv6 range start address must be unique - two ranges can't + # start with the same address - makes no sense + if start in range6_start: + raise ConfigError('Conflicting DHCPv6 lease range:\n' \ + 'Pool start address {0} defined multipe times!'.format(start)) + else: + range6_start.append(start) + + # DHCPv6 range stop address must be unique - two ranges can't + # end with the same address - makes no sense + if stop in range6_stop: + raise ConfigError('Conflicting DHCPv6 lease range:\n' \ + 'Pool stop address {0} defined multipe times!'.format(stop)) + else: + range6_stop.append(stop) + + # We also have prefixes that require checking + for prefix in subnet['range6_prefix']: + # If configured prefix does not match our subnet, we have to check that it's inside + if ipaddress.ip_network(prefix['prefix']) != ipaddress.ip_network(subnet['network']): + # Configured prefixes must be inside our network + if not ipaddress.ip_network(prefix['prefix']) in ipaddress.ip_network(subnet['network']): + raise ConfigError('DHCPv6 prefix {0} is not in subnet {1}\n' \ + 'specified for shared network {2}!'.format(prefix['prefix'], subnet['network'], network['name'])) + + # DHCPv6 requires at least one configured address range or one static mapping + if not network['disabled']: + if vyos.validate.is_subnet_connected(subnet['network']): + listen_ok = True + + # DHCPv6 subnet must not overlap. ISC DHCP also complains about overlapping + # subnets: "Warning: subnet 2001:db8::/32 overlaps subnet 2001:db8:1::/32" + net = ipaddress.ip_network(subnet['network']) + for n in subnets: + net2 = ipaddress.ip_network(n) + if (net != net2): + if net.overlaps(net2): + raise ConfigError('DHCPv6 conflicting subnet ranges: {0} overlaps {1}'.format(net, net2)) + + if not listen_ok: + raise ConfigError('None of the DHCPv6 subnets are connected to a subnet6 on\n' \ + 'this machine. At least one subnet6 must be connected such that\n' \ + 'DHCPv6 listens on an interface!') + return None -- cgit v1.2.3