# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license
# Copyright (C) 2001-2017 Nominum, Inc.
#
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# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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"""DNS Opcodes."""
import dns.enum
import dns.exception
[docs]
class Opcode(dns.enum.IntEnum):
#: Query
QUERY = 0
#: Inverse Query (historical)
IQUERY = 1
#: Server Status (unspecified and unimplemented anywhere)
STATUS = 2
#: Notify
NOTIFY = 4
#: Dynamic Update
UPDATE = 5
@classmethod
def _maximum(cls):
return 15
@classmethod
def _unknown_exception_class(cls) -> type[Exception]:
return UnknownOpcode
[docs]
class UnknownOpcode(dns.exception.DNSException):
"""An DNS opcode is unknown."""
[docs]
def from_text(text: str) -> Opcode:
"""Convert text into an opcode.
:param text: The textual opcode.
:type text: str
:raises dns.opcode.UnknownOpcode: If the opcode is unknown.
:rtype: :py:class:`dns.opcode.Opcode`
"""
return Opcode.from_text(text)
[docs]
def from_flags(flags: int) -> Opcode:
"""Extract an opcode from DNS message flags.
:param flags: The DNS message flags.
:type flags: int
:rtype: :py:class:`dns.opcode.Opcode`
"""
return Opcode((flags & 0x7800) >> 11)
[docs]
def to_flags(value: Opcode) -> int:
"""Convert an opcode to a value suitable for ORing into DNS message
flags.
:param value: The DNS opcode value.
:type value: :py:class:`dns.opcode.Opcode`
:rtype: int
"""
return (value << 11) & 0x7800
[docs]
def to_text(value: Opcode) -> str:
"""Convert an opcode to text.
:param value: The opcode value.
:type value: :py:class:`dns.opcode.Opcode`
:raises dns.opcode.UnknownOpcode: If the opcode is unknown.
:rtype: str
"""
return Opcode.to_text(value)
[docs]
def is_update(flags: int) -> bool:
"""Is the opcode in flags UPDATE?
:param flags: The DNS message flags.
:type flags: int
:rtype: bool
"""
return from_flags(flags) == Opcode.UPDATE
### BEGIN generated Opcode constants
QUERY = Opcode.QUERY
IQUERY = Opcode.IQUERY
STATUS = Opcode.STATUS
NOTIFY = Opcode.NOTIFY
UPDATE = Opcode.UPDATE
### END generated Opcode constants