# Copyright (C) Dnspython Contributors, see LICENSE for text of ISC license # Copyright (C) 2003-2017 Nominum, Inc. # Copyright (C) 2016 Coresec Systems AB # # 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. # # THE SOFTWARE IS PROVIDED "AS IS" AND CORESEC SYSTEMS AB DISCLAIMS ALL # WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED # WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL CORESEC # SYSTEMS AB 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. """DNS name dictionary""" # pylint seems to be confused about this one! from collections.abc import MutableMapping # pylint: disable=no-name-in-module import dns.name class NameDict(MutableMapping): """A dictionary whose keys are dns.name.Name objects. In addition to being like a regular Python dictionary, this dictionary can also get the deepest match for a given key. """ __slots__ = ["max_depth", "max_depth_items", "__store"] def __init__(self, *args, **kwargs): super().__init__() self.__store = dict() #: the maximum depth of the keys that have ever been added self.max_depth = 0 #: the number of items of maximum depth self.max_depth_items = 0 self.update(dict(*args, **kwargs)) def __update_max_depth(self, key): if len(key) == self.max_depth: self.max_depth_items = self.max_depth_items + 1 elif len(key) > self.max_depth: self.max_depth = len(key) self.max_depth_items = 1 def __getitem__(self, key): return self.__store[key] def __setitem__(self, key, value): if not isinstance(key, dns.name.Name): raise ValueError("NameDict key must be a name") self.__store[key] = value self.__update_max_depth(key) def __delitem__(self, key): self.__store.pop(key) if len(key) == self.max_depth: self.max_depth_items = self.max_depth_items - 1 if self.max_depth_items == 0: self.max_depth = 0 for k in self.__store: self.__update_max_depth(k) def __iter__(self): return iter(self.__store) def __len__(self): return len(self.__store) def has_key(self, key): return key in self.__store def get_deepest_match(self, name): """Find the deepest match to *name* in the dictionary. The deepest match is the longest name in the dictionary which is a superdomain of *name*. Note that *superdomain* includes matching *name* itself. *name*, a ``dns.name.Name``, the name to find. Returns a ``(key, value)`` where *key* is the deepest ``dns.name.Name``, and *value* is the value associated with *key*. """ depth = len(name) if depth > self.max_depth: depth = self.max_depth for i in range(-depth, 0): n = dns.name.Name(name[i:]) if n in self: return (n, self[n]) v = self[dns.name.empty] return (dns.name.empty, v)