-import re
-from ipaddress import IPv4Address, IPv6Address
-from typing import List, Dict, Any, Iterator
-
-
-second = 1
-minute = 60*second
-hour = 60*minute
-day = 24*hour
-week = 7*day
-
-def check_hostname(name: str) -> str:
- # check hostname for validity
- label = r'[a-zA-Z90-9]([a-zA-Z90-9-]{0,61}[a-zA-Z90-9])?' # must not start or end with hyphen
- pattern = r'^{0}(\.{0})*\.?'.format(label)
- if re.match(pattern, name):
- return name
- raise Exception(name+" is not a valid hostname")
-
-def time(time: int) -> str:
- if time == 0:
- return "0"
- elif time % week == 0:
- return str(time//week)+"w"
- elif time % day == 0:
- return str(time//day)+"d"
- elif time % hour == 0:
- return str(time//hour)+"h"
- elif time % minute == 0:
- return str(time//minute)+"m"
- else:
- return str(time)
-
-class Address:
- # mypy does not know about the ipaddress types, so leave this class unannotated for now
- def __init__(self, IPv4 = None, IPv6 = None) -> None:
- if IPv4 is None and IPv6 is None:
- raise Exception("There has to be at least one valid address!")
- self._IPv4 = None if IPv4 is None else IPv4Address(IPv4)
- self._IPv6 = None if IPv6 is None else IPv6Address(IPv6)
-
- def IPv4(self):
- return Address(IPv4 = self._IPv4)
-
- def IPv6(self):
- return Address(IPv6 = self._IPv6)
-
- def generate_rrs(self, owner: str, zone: 'Zone') -> Iterator:
- if self._IPv4 is not None:
- yield zone.RR(owner, 'A', self._IPv4)
- if self._IPv6 is not None:
- yield zone.RR(owner, 'AAAA', self._IPv6)
-
-class Name:
- def __init__(self, address: Address = None, MX: List = None,
- TCP: Dict[int, Any] = None, UDP: Dict[int, Any] = None) -> None:
- self._address = address
-
- def generate_rrs(self, owner: str, zone: 'Zone') -> Iterator:
- if self._address is not None:
- for rr in self._address.generate_rrs(owner, zone):
- yield rr
- # TODO
-
-class Service:
- def __init__(self, SRV: str = None, TLSA: str=None) -> None:
- self._SRV = None if SRV is None else check_hostname(SRV)
- self._TLSA = TLSA
-
-class CName:
- def __init__(self, name: str) -> None:
- self._name = check_hostname(name)
-
- def generate_rrs(self, owner: str, zone: 'Zone') -> Iterator:
- yield zone.RR(owner, 'CNAME', zone.abs_hostname(self._name))
-
-class Delegation():
- def __init__(self, NS: str, DS: str = None) -> None:
- self._NS = NS
- self._DS = DS
-
- def generate_rrs(self, owner: str, zone: 'Zone') -> Iterator:
- yield zone.RR(owner, 'NS', zone.abs_hostname(self._NS))
- # TODO DS
-
-class Zone:
- def __init__(self, name: str, serialfile: str, dbfile: str, mail: str, NS: List[str],
- secondary_refresh: int, secondary_retry: int, secondary_expire: int,
- NX_TTL: int = None, A_TTL: int = None, other_TTL: int = None,
- domains: Dict[str, Any] = {}) -> None:
- self._serialfile = serialfile
- self._dbfile = dbfile
-
- if not name.endswith('.'): raise Exception("Expected an absolute hostname")
- self._name = check_hostname(name)
- if not mail.endswith('.'): raise Exception("Mail must be absolute, end with a dot")
- atpos = mail.find('@')
- if atpos < 0 or atpos > mail.find('.'): raise Exception("Mail must contain an @ before the first dot")
- self._mail = check_hostname(mail.replace('@', '.', 1))
- self._NS = list(map(check_hostname, NS))
-
- self._refresh = secondary_refresh
- self._retry = secondary_retry
- self._expire = secondary_expire
-
- if other_TTL is None: raise Exception("Must give other_TTL")
- self._NX_TTL = NX_TTL
- self._A_TTL = self._AAAA_TTL = A_TTL
- self._other_TTL = other_TTL
-
- self._domains = domains
-
- def RR(self, owner: str, recordType: str, data: str) -> str:
- '''generate given RR, in textual representation'''
- assert re.match(r'^[A-Z]+$', recordType), "got invalid record type"
- # figure out TTL
- attrname = "_"+recordType+"_TTL"
- TTL = None # type: int
- if hasattr(self, attrname):
- TTL = getattr(self, attrname)
- if TTL is None:
- TTL = self._other_TTL
- # be done
- return "{0}\t{1}\t{2}\t{3}".format(self.abs_hostname(owner), TTL, recordType, data)
-
- def abs_hostname(self, name):
- if name.endswith('.'):
- return name
- return name+"."+self._name
-
- def inc_serial(self) -> int:
- # get serial
- cur_serial = 0
- try:
- with open(self._serialfile) as f:
- cur_serial = int(f.read())
- except FileNotFoundError:
- pass
- # increment serial
- cur_serial += 1
- # save serial
- with open(self._serialfile, 'w') as f:
- f.write(str(cur_serial))
- # be done
- return cur_serial
-
- def generate_rrs(self) -> Iterator:
- # SOA record
- serial = self.inc_serial()
- yield self.RR(self._name, 'SOA',
- ('{NS} {mail} ({serial} {refresh} {retry} {expire} {NX_TTL}) ; '+
- '(serial refresh retry expire NX_TTL)').format(
- NS=self.abs_hostname(self._NS[0]), mail=self._mail, serial=serial,
- refresh=time(self._refresh), retry=time(self._retry), expire=time(self._expire),
- NX_TTL=time(self._NX_TTL))
- )
- # NS records
- for ns in self._NS:
- yield self.RR(self._name, 'NS', self.abs_hostname(ns))
-
- # all the rest
- for name in sorted(self._domains.keys(), key=lambda s: list(reversed(s.split('.')))):
- for rr in self._domains[name].generate_rrs(name, self):
- yield rr
-
- def write(self) -> None:
- for rr in self.generate_rrs():
- print(rr)