# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license # Copyright (C) 2006-2017 Nominum, Inc. # # Permission to use, copy, modify, and distribute this software and its # 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. # # THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT # OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. """TXT-like base class.""" from typing import Any, Dict, Iterable, Optional, Tuple, Union import dns.exception import dns.immutable import dns.rdata import dns.renderer import dns.tokenizer @dns.immutable.immutable class TXTBase(dns.rdata.Rdata): """Base class for rdata that is like a TXT record (see RFC 1035).""" __slots__ = ["strings"] def __init__( self, rdclass: dns.rdataclass.RdataClass, rdtype: dns.rdatatype.RdataType, strings: Iterable[Union[bytes, str]], ): """Initialize a TXT-like rdata. *rdclass*, an ``int`` is the rdataclass of the Rdata. *rdtype*, an ``int`` is the rdatatype of the Rdata. *strings*, a tuple of ``bytes`` """ super().__init__(rdclass, rdtype) self.strings: Tuple[bytes] = self._as_tuple( strings, lambda x: self._as_bytes(x, True, 255) ) def to_text( self, origin: Optional[dns.name.Name] = None, relativize: bool = True, **kw: Dict[str, Any], ) -> str: txt = "" prefix = "" for s in self.strings: txt += '{}"{}"'.format(prefix, dns.rdata._escapify(s)) prefix = " " return txt @classmethod def from_text( cls, rdclass: dns.rdataclass.RdataClass, rdtype: dns.rdatatype.RdataType, tok: dns.tokenizer.Tokenizer, origin: Optional[dns.name.Name] = None, relativize: bool = True, relativize_to: Optional[dns.name.Name] = None, ) -> dns.rdata.Rdata: strings = [] for token in tok.get_remaining(): token = token.unescape_to_bytes() # The 'if' below is always true in the current code, but we # are leaving this check in in case things change some day. if not ( token.is_quoted_string() or token.is_identifier() ): # pragma: no cover raise dns.exception.SyntaxError("expected a string") if len(token.value) > 255: raise dns.exception.SyntaxError("string too long") strings.append(token.value) if len(strings) == 0: raise dns.exception.UnexpectedEnd return cls(rdclass, rdtype, strings) def _to_wire(self, file, compress=None, origin=None, canonicalize=False): for s in self.strings: with dns.renderer.prefixed_length(file, 1): file.write(s) @classmethod def from_wire_parser(cls, rdclass, rdtype, parser, origin=None): strings = [] while parser.remaining() > 0: s = parser.get_counted_bytes() strings.append(s) return cls(rdclass, rdtype, strings)