diff options
Diffstat (limited to 'python/vyos')
| -rw-r--r-- | python/vyos/template.py | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/python/vyos/template.py b/python/vyos/template.py index 527384d0b..22883b103 100644 --- a/python/vyos/template.py +++ b/python/vyos/template.py @@ -288,7 +288,6 @@ def compare_netmask(netmask1, netmask2): except: return False - @register_filter('isc_static_route') def isc_static_route(subnet, router): # https://ercpe.de/blog/pushing-static-routes-with-isc-dhcp-server @@ -316,3 +315,22 @@ def is_file(filename): if os.path.exists(filename): return os.path.isfile(filename) return False + +@register_filter('get_dhcp_router') +def get_dhcp_router(interface): + """ Static routes can point to a router received by a DHCP reply. This + helper is used to get the current default router from the DHCP reply. + + Returns False of no router is found, returns the IP address as string if + a router is found. + """ + interface = interface.replace('.', '_') + lease_file = f'/var/lib/dhcp/dhclient_{interface}.leases' + if not os.path.exists(lease_file): + return None + + from vyos.util import read_file + for line in read_file(lease_file).splitlines(): + if 'option routers' in line: + (_, _, address) = line.split() + return address.rstrip(';') |