Files
vppcfg/config/tap.py
2022-04-09 19:56:48 +00:00

102 lines
3.6 KiB
Python

#
# Copyright (c) 2022 Pim van Pelt
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at:
# http://www.apache.org/licenses/LICENSE-2.0
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
import logging
import config.mac as mac
def get_taps(yaml):
""" Return a list of all taps. """
ret = []
if 'taps' in yaml:
for ifname, iface in yaml['taps'].items():
ret.append(ifname)
return ret
def get_by_name(yaml, ifname):
""" Return the tap by name, if it exists. Return None otherwise. """
try:
if ifname in yaml['taps']:
return ifname, yaml['taps'][ifname]
except:
pass
return None, None
def is_tap(yaml, ifname):
""" Returns True if the interface name is an existing tap in the config.
The TAP has to be explicitly named in the configuration, and notably
a TAP belonging to a Linux Control Plane (LCP) will return False.
"""
ifname, iface = get_by_name(yaml, ifname)
return not iface == None
def is_host_name_unique(yaml, hostname):
""" Returns True if there is at most one occurence of the given ifname amonst all host-names of TAPs. """
if not 'taps' in yaml:
return True
host_names = []
for tap_ifname, tap_iface in yaml['taps'].items():
host_names.append(tap_iface['host']['name'])
return host_names.count(hostname) < 2
def validate_taps(yaml):
result = True
msgs = []
logger = logging.getLogger('vppcfg.config')
logger.addHandler(logging.NullHandler())
if not 'taps' in yaml:
return result, msgs
for ifname, iface in yaml['taps'].items():
logger.debug("tap %s" % iface)
instance = int(ifname[3:])
## NOTE(pim): 1024 is not off-by-one, tap1024 is precisely the highest permissible id
if instance > 1024:
msgs.append("tap %s has instance %d which is too large" % (ifname, instance))
result = False
if not is_host_name_unique(yaml, iface['host']['name']):
msgs.append("tap %s does not have a unique host name %s" % (ifname, iface['host']['name']))
result = False
if 'rx-ring-size' in iface:
n = iface['rx-ring-size']
if n & (n-1) != 0:
msgs.append("tap %s rx-ring-size must be a power of two" % (ifname))
result = False
if 'tx-ring-size' in iface:
n = iface['tx-ring-size']
if n & (n-1) != 0:
msgs.append("tap %s tx-ring-size must be a power of two" % (ifname))
result = False
if 'namespace-create' in iface['host'] and iface['host']['namespace-create'] and not 'namespace' in iface['host']:
msgs.append("tap %s namespace-create can only be set if namespace is set" % (ifname))
result = False
if 'bridge-create' in iface['host'] and iface['host']['bridge-create'] and not 'bridge' in iface['host']:
msgs.append("tap %s bridge-create can only be set if bridge is set" % (ifname))
result = False
if 'mac' in iface['host'] and mac.is_multicast(iface['host']['mac']):
msgs.append("tap %s host MAC address %s cannot be multicast" % (ifname, iface['host']['mac']))
result = False
return result, msgs