| OLD | NEW |
| (Empty) | |
| 1 # Copyright (C) 2009 Nominum, Inc. |
| 2 # |
| 3 # Permission to use, copy, modify, and distribute this software and its |
| 4 # documentation for any purpose with or without fee is hereby granted, |
| 5 # provided that the above copyright notice and this permission notice |
| 6 # appear in all copies. |
| 7 # |
| 8 # THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES |
| 9 # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF |
| 10 # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR |
| 11 # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| 12 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN |
| 13 # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT |
| 14 # OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| 15 |
| 16 """EDNS Options""" |
| 17 |
| 18 NSID = 3 |
| 19 |
| 20 class Option(object): |
| 21 """Base class for all EDNS option types. |
| 22 """ |
| 23 |
| 24 def __init__(self, otype): |
| 25 """Initialize an option. |
| 26 @param rdtype: The rdata type |
| 27 @type rdtype: int |
| 28 """ |
| 29 self.otype = otype |
| 30 |
| 31 def to_wire(self, file): |
| 32 """Convert an option to wire format. |
| 33 """ |
| 34 raise NotImplementedError |
| 35 |
| 36 def from_wire(cls, otype, wire, current, olen): |
| 37 """Build an EDNS option object from wire format |
| 38 |
| 39 @param otype: The option type |
| 40 @type otype: int |
| 41 @param wire: The wire-format message |
| 42 @type wire: string |
| 43 @param current: The offet in wire of the beginning of the rdata. |
| 44 @type current: int |
| 45 @param olen: The length of the wire-format option data |
| 46 @type olen: int |
| 47 @rtype: dns.ends.Option instance""" |
| 48 raise NotImplementedError |
| 49 |
| 50 from_wire = classmethod(from_wire) |
| 51 |
| 52 def _cmp(self, other): |
| 53 """Compare an ENDS option with another option of the same type. |
| 54 Return < 0 if self < other, 0 if self == other, and > 0 if self > other. |
| 55 """ |
| 56 raise NotImplementedError |
| 57 |
| 58 def __eq__(self, other): |
| 59 if not isinstance(other, Option): |
| 60 return False |
| 61 if self.otype != other.otype: |
| 62 return False |
| 63 return self._cmp(other) == 0 |
| 64 |
| 65 def __ne__(self, other): |
| 66 if not isinstance(other, Option): |
| 67 return False |
| 68 if self.otype != other.otype: |
| 69 return False |
| 70 return self._cmp(other) != 0 |
| 71 |
| 72 def __lt__(self, other): |
| 73 if not isinstance(other, Option) or \ |
| 74 self.otype != other.otype: |
| 75 return NotImplemented |
| 76 return self._cmp(other) < 0 |
| 77 |
| 78 def __le__(self, other): |
| 79 if not isinstance(other, Option) or \ |
| 80 self.otype != other.otype: |
| 81 return NotImplemented |
| 82 return self._cmp(other) <= 0 |
| 83 |
| 84 def __ge__(self, other): |
| 85 if not isinstance(other, Option) or \ |
| 86 self.otype != other.otype: |
| 87 return NotImplemented |
| 88 return self._cmp(other) >= 0 |
| 89 |
| 90 def __gt__(self, other): |
| 91 if not isinstance(other, Option) or \ |
| 92 self.otype != other.otype: |
| 93 return NotImplemented |
| 94 return self._cmp(other) > 0 |
| 95 |
| 96 |
| 97 class GenericOption(Option): |
| 98 """Generate Rdata Class |
| 99 |
| 100 This class is used for EDNS option types for which we have no better |
| 101 implementation. |
| 102 """ |
| 103 |
| 104 def __init__(self, otype, data): |
| 105 super(GenericOption, self).__init__(otype) |
| 106 self.data = data |
| 107 |
| 108 def to_wire(self, file): |
| 109 file.write(self.data) |
| 110 |
| 111 def from_wire(cls, otype, wire, current, olen): |
| 112 return cls(otype, wire[current : current + olen]) |
| 113 |
| 114 from_wire = classmethod(from_wire) |
| 115 |
| 116 def _cmp(self, other): |
| 117 return cmp(self.data, other.data) |
| 118 |
| 119 _type_to_class = { |
| 120 } |
| 121 |
| 122 def get_option_class(otype): |
| 123 cls = _type_to_class.get(otype) |
| 124 if cls is None: |
| 125 cls = GenericOption |
| 126 return cls |
| 127 |
| 128 def option_from_wire(otype, wire, current, olen): |
| 129 """Build an EDNS option object from wire format |
| 130 |
| 131 @param otype: The option type |
| 132 @type otype: int |
| 133 @param wire: The wire-format message |
| 134 @type wire: string |
| 135 @param current: The offet in wire of the beginning of the rdata. |
| 136 @type current: int |
| 137 @param olen: The length of the wire-format option data |
| 138 @type olen: int |
| 139 @rtype: dns.ends.Option instance""" |
| 140 |
| 141 cls = get_option_class(otype) |
| 142 return cls.from_wire(otype, wire, current, olen) |
| OLD | NEW |