
  $   ˆl–Ým_Jå0–54 ^¸Ëw%1hßÅ„„Ó?ÄÀÂ /Ó    # Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license

# Copyright (C) 2003-2007, 2009-2011 Nominum, Inc.
#
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# documentation for any purpose with or without fee is hereby granted,
# provided that the above copyright notice and this permission notice
# appear in all copies.
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# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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"""DNS Dynamic Update Support"""

from typing import Any, List, Optional, Union

import dns.message
import dns.name
import dns.opcode
import dns.rdata
import dns.rdataclass
import dns.rdataset
import dns.rdatatype
import dns.tsig


class UpdateSection(dns.enum.IntEnum):
    """Update sections"""

    ZONE = 0
    PREREQ = 1
    UPDATE = 2
    ADDITIONAL = 3

    @classmethod
    def _maximum(cls):
        return 3


class UpdateMessage(dns.message.Message):  # lgtm[py/missing-equals]
    # ignore the mypy error here as we mean to use a different enum
    _section_enum = UpdateSection  # type: ignore

    def __init__(
        self,
        zone: Optional[Union[dns.name.Name, str]] = None,
        rdclass: dns.rdataclass.RdataClass = dns.rdataclass.IN,
        keyring: Optional[Any] = None,
        keyname: Optional[dns.name.Name] = None,
        keyalgorithm: Union[dns.name.Name, str] = dns.tsig.default_algorithm,
        id: Optional[int] = None,
    ):
        """Initialize a new DNS Update object.

        See the documentation of the Message class for a complete
        description of the keyring dictionary.

        *zone*, a ``dns.name.Name``, ``str``, or ``None``, the zone
        which is being updated.  ``None`` should only be used by dnspython's
        message constructors, as a zone is required for the convenience
        methods like ``add()``, ``replace()``, etc.

        *rdclass*, an ``int`` or ``str``, the class of the zone.

        The *keyring*, *keyname*, and *keyalgorithm* parameters are passed to
        ``use_tsig()``; see its documentation for details.
        """
        super().__init__(id=id)
        self.flags |= dns.opcode.to_flags(dns.opcode.UPDATE)
        if isinstance(zone, str):
            zone = dns.name.from_text(zone)
        self.origin = zone
        rdclass = dns.rdataclass.RdataClass.make(rdclass)
        self.zone_rdclass = rdclass
        if self.origin:
            self.find_rrset(
                self.zone,
                self.origin,
                rdclass,
                dns.rdatatype.SOA,
                create=True,
                force_unique=True,
            )
        if keyring is not None:
            self.use_tsig(keyring, keyname, algorithm=keyalgorithm)

    @property
    def zone(self) -> List[dns.rrset.RRset]:
        """The zone section."""
        return self.sections[0]

    @zone.setter
    def zone(self, v):
        self.sections[0] = v

    @property
    def prerequisite(self) -> List[dns.rrset.RRset]:
        """The prerequisite section."""
        return self.sections[1]

    @prerequisite.setter
    def prerequisite(self, v):
        self.sections[1] = v

    @property
    def update(self) -> List[dns.rrset.RRset]:
        """The update section."""
        return self.sections[2]

    @update.setter
    def update(self, v):
        self.sections[2] = v

    def _add_rr(self, name, ttl, rd, deleting=None, section=None):
        """Add a single RR to the update section."""

        if section is None:
            section = self.update
        covers = rd.covers()
        rrset = self.find_rrset(
            section, name, self.zone_rdclass, rd.rdtyp