FreedomBox/plinth/modules/bind/privileged.py
Sunil Mohan Adapa cdb04bb46a
bind: Use privileged decorator for actions
Tests:

- Initial setup:
  - Creates zones directory
  - Write default configuration
  - named is restarted
- Forwarders
  - Setting forwarders works as expected.
  - Current list of forwarders is shown as expected
- List of served domains is shown properly

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>
2022-10-08 18:51:21 -04:00

199 lines
6.1 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-or-later
"""Configuration helper for BIND server."""
import re
from collections import defaultdict
from pathlib import Path
import augeas
from plinth import action_utils
from plinth.actions import privileged
CONFIG_FILE = '/etc/bind/named.conf.options'
ZONES_DIR = '/var/bind/pri'
DEFAULT_CONFIG = '''
acl goodclients {
localnets;
};
options {
directory "/var/cache/bind";
recursion yes;
allow-query { goodclients; };
forwarders {
};
forward first;
dnssec-enable yes;
dnssec-validation auto;
auth-nxdomain no; # conform to RFC1035
listen-on-v6 { any; };
};
'''
@privileged
def setup(old_version: int):
"""Setup BIND configuration."""
if old_version == 0:
with open(CONFIG_FILE, 'w', encoding='utf-8') as conf_file:
conf_file.write(DEFAULT_CONFIG)
Path(ZONES_DIR).mkdir(exist_ok=True, parents=True)
action_utils.service_restart('named')
@privileged
def configure(forwarders: str, dnssec: bool):
"""Configure BIND."""
_set_forwarders(forwarders)
_set_dnssec(dnssec)
action_utils.service_restart('named')
def get_config():
"""Get current configuration."""
data = [line.strip() for line in open(CONFIG_FILE, 'r', encoding='utf-8')]
forwarders = ''
dnssec_enabled = False
flag = False
for line in data:
if re.match(r'^\s*forwarders\s+{', line):
flag = True
elif re.match(r'^\s*dnssec-enable\s+yes;', line):
dnssec_enabled = True
elif flag and '//' not in line:
forwarders = re.sub('[;]', '', line)
flag = False
conf = {
'forwarders': forwarders,
'enable_dnssec': dnssec_enabled,
}
return conf
def _set_forwarders(forwarders):
"""Set DNS forwarders."""
flag = 0
data = [line.strip() for line in open(CONFIG_FILE, 'r', encoding='utf-8')]
conf_file = open(CONFIG_FILE, 'w', encoding='utf-8')
for line in data:
if re.match(r'^\s*forwarders\s+{', line):
conf_file.write(line + '\n')
for dns in forwarders.split():
conf_file.write(dns + '; ')
conf_file.write('\n')
flag = 1
elif '};' in line and flag == 1:
conf_file.write(line + '\n')
flag = 0
elif flag == 0:
conf_file.write(line + '\n')
conf_file.close()
def _set_dnssec(choice):
"""Enable or disable DNSSEC."""
data = [line.strip() for line in open(CONFIG_FILE, 'r', encoding='utf-8')]
if choice:
conf_file = open(CONFIG_FILE, 'w', encoding='utf-8')
for line in data:
if re.match(r'//\s*dnssec-enable\s+yes;', line):
line = line.lstrip('/')
conf_file.write(line + '\n')
conf_file.close()
else:
conf_file = open(CONFIG_FILE, 'w', encoding='utf-8')
for line in data:
if re.match(r'^\s*dnssec-enable\s+yes;', line):
line = '//' + line
conf_file.write(line + '\n')
conf_file.close()
def get_served_domains():
"""Return list of domains service handles.
Augeas path for zone files:
===========================
augtool> print /files/var/bind/pri/local.zone
/files/var/bind/pri/local.zone
/files/var/bind/pri/local.zone/$TTL = "604800"
/files/var/bind/pri/local.zone/@[1]
/files/var/bind/pri/local.zone/@[1]/1
/files/var/bind/pri/local.zone/@[1]/1/class = "IN"
/files/var/bind/pri/local.zone/@[1]/1/type = "SOA"
/files/var/bind/pri/local.zone/@[1]/1/mname = "localhost."
/files/var/bind/pri/local.zone/@[1]/1/rname = "root.localhost."
/files/var/bind/pri/local.zone/@[1]/1/serial = "2"
/files/var/bind/pri/local.zone/@[1]/1/refresh = "604800"
/files/var/bind/pri/local.zone/@[1]/1/retry = "86400"
/files/var/bind/pri/local.zone/@[1]/1/expiry = "2419200"
/files/var/bind/pri/local.zone/@[1]/1/minimum = "604800"
/files/var/bind/pri/local.zone/@[2]
/files/var/bind/pri/local.zone/@[2]/1
/files/var/bind/pri/local.zone/@[2]/1/class = "IN"
/files/var/bind/pri/local.zone/@[2]/1/type = "NS"
/files/var/bind/pri/local.zone/@[2]/1/rdata = "localhost."
/files/var/bind/pri/local.zone/@[3]
/files/var/bind/pri/local.zone/@[3]/1
/files/var/bind/pri/local.zone/@[3]/1/class = "IN"
/files/var/bind/pri/local.zone/@[3]/1/type = "A"
/files/var/bind/pri/local.zone/@[3]/1/rdata = "127.0.0.1"
/files/var/bind/pri/local.zone/@[4]
/files/var/bind/pri/local.zone/@[4]/1
/files/var/bind/pri/local.zone/@[4]/1/class = "IN"
/files/var/bind/pri/local.zone/@[4]/1/type = "AAAA"
/files/var/bind/pri/local.zone/@[4]/1/rdata = "::1"
Need to find the related functionality to parse the A records
Retrieve from /etc/bind/db* zone files all the configured A records.
Assuming zones files in ZONES_DIR are all used.
:return: dictionary in the form 'domain_name': ['ip_address', 'ipv6_addr']
"""
RECORD_TYPES = ('A', 'AAAA')
aug = augeas.Augeas(flags=augeas.Augeas.NO_LOAD +
augeas.Augeas.NO_MODL_AUTOLOAD)
aug.set('/augeas/load/Dns_Zone/lens', 'Dns_Zone.lns')
zone_file_path = Path(ZONES_DIR)
zone_files = [zf for zf in zone_file_path.iterdir() if zf.is_file()]
# augeas load only required files
for zone_file in zone_files:
aug.set('/augeas/load/Dns_Zone/incl[last() + 1]', str(zone_file))
aug.load()
served_domains = defaultdict(list)
for zone_file in zone_files:
base_path = '/files/%s/@[{record_order}]/1/{field}' % zone_file
count = 1
mname = aug.get(base_path.format(record_order=count, field='mname'))
while True:
record_type = aug.get(
base_path.format(record_order=count, field='type'))
# no record type ends the search
if record_type is None:
break
if record_type in RECORD_TYPES:
served_domains[mname].append(
aug.get(base_path.format(record_order=count,
field='rdata')))
count += 1
return served_domains