Stem Docs

stem.descriptor.tordnsel

Source code for stem.descriptor.tordnsel

# Copyright 2013-2017, Damian Johnson and The Tor Project
# See LICENSE for licensing information

"""
Parsing for `TorDNSEL <https://www.torproject.org/projects/tordnsel.html.en>`_
exit list files.

::

  TorDNSEL - Exit list provided by TorDNSEL
"""

import stem.util.connection
import stem.util.str_tools
import stem.util.tor_tools

from stem.descriptor import (
  Descriptor,
  _read_until_keywords,
  _descriptor_components,
)


def _parse_file(tordnsel_file, validate = False, **kwargs):
  """
  Iterates over a tordnsel file.

  :returns: iterator for :class:`~stem.descriptor.tordnsel.TorDNSEL`
    instances in the file

  :raises:
    * **ValueError** if the contents is malformed and validate is **True**
    * **IOError** if the file can't be read
  """

  # skip content prior to the first ExitNode
  _read_until_keywords('ExitNode', tordnsel_file, skip = True)

  while True:
    contents = _read_until_keywords('ExitAddress', tordnsel_file)
    contents += _read_until_keywords('ExitNode', tordnsel_file)

    if contents:
      yield TorDNSEL(bytes.join(b'', contents), validate, **kwargs)
    else:
      break  # done parsing file


[docs]class TorDNSEL(Descriptor): """ TorDNSEL descriptor (`exitlist specification <https://www.torproject.org/tordnsel/exitlist-spec.txt>`_) :var str fingerprint: **\*** authority's fingerprint :var datetime published: **\*** time in UTC when this descriptor was made :var datetime last_status: **\*** time in UTC when the relay was seen in a v2 network status :var list exit_addresses: **\*** list of (str address, datetime date) tuples consisting of the found IPv4 exit address and the time **\*** attribute is either required when we're parsed with validation or has a default value, others are left as **None** if undefined """ def __init__(self, raw_contents, validate): super(TorDNSEL, self).__init__(raw_contents) raw_contents = stem.util.str_tools._to_unicode(raw_contents) entries = _descriptor_components(raw_contents, validate) self.fingerprint = None self.published = None self.last_status = None self.exit_addresses = [] self._parse(entries, validate) def _parse(self, entries, validate): for keyword, values in list(entries.items()): value, block_type, block_content = values[0] if validate and block_content: raise ValueError('Unexpected block content: %s' % block_content) if keyword == 'ExitNode': if validate and not stem.util.tor_tools.is_valid_fingerprint(value): raise ValueError('Tor relay fingerprints consist of forty hex digits: %s' % value) self.fingerprint = value elif keyword == 'Published': try: self.published = stem.util.str_tools._parse_timestamp(value) except ValueError: if validate: raise ValueError("Published time wasn't parsable: %s" % value) elif keyword == 'LastStatus': try: self.last_status = stem.util.str_tools._parse_timestamp(value) except ValueError: if validate: raise ValueError("LastStatus time wasn't parsable: %s" % value) elif keyword == 'ExitAddress': for value, block_type, block_content in values: address, date = value.split(' ', 1) if validate: if not stem.util.connection.is_valid_ipv4_address(address): raise ValueError("ExitAddress isn't a valid IPv4 address: %s" % address) elif block_content: raise ValueError('Unexpected block content: %s' % block_content) try: date = stem.util.str_tools._parse_timestamp(date) self.exit_addresses.append((address, date)) except ValueError: if validate: raise ValueError("ExitAddress found time wasn't parsable: %s" % value) elif validate: raise ValueError('Unrecognized keyword: %s' % keyword)