Bug28715 01

sbws/util/stem.py

@@ -117,6 +117,52 @@ def _init_controller_socket(socket):
  return c
 
 
+def parse_user_torrc_config(torrc, torrc_text):
+ """Parse the user configuration torrc text call `extra_lines`
+ to a dictionary suitable to use with stem and return a new torrc
+ dictionary that merges that dictionary with the existing torrc.
+ Example:
+ [tor]
+ extra_lines =
+ Log debug file /tmp/tor-debug.log
+ NumCPUs 1
+ """
+ torrc_dict = torrc.copy()
+ for line in torrc_text.split('\n'):
+ # Remove leading and trailing whitespace, if any
+ line = line.strip()
+ # Ignore blank lines
+ if len(line) < 1:
+ continue
+ # Some torrc options are only a key, some are a key value pair.
+ kv = line.split(None, 1)
+ if len(kv) > 1:
+ key, value = kv
+ else:
+ key = kv[0]
+ value = None
+ # It's really easy to add to the torrc if the key doesn't exist
+ if key not in torrc:
+ torrc_dict.update({key: value})
+ # But if it does, we have to make a list of values. For example, say
+ # the user wants to add a SocksPort and we already have
+ # 'SocksPort auto' in the torrc. We'll go from
+ # torrc['SocksPort'] == 'auto'
+ # to
+ # torrc['SocksPort'] == ['auto', '9050']
+ else:
+ existing_val = torrc[key]
+ if isinstance(existing_val, str):
+ torrc_dict.update({key: [existing_val, value]})
+ else:
+ assert isinstance(existing_val, list)
+ existing_val.append(value)
+ torrc_dict.update({key: existing_val})
+ log.debug('Adding "%s %s" to torrc with which we are launching Tor',
+ key, value)
+ return torrc_dict
+
+
 def launch_tor(conf):
  assert isinstance(conf, ConfigParser)
  os.makedirs(conf.getpath('tor', 'datadir'), mode=0o700, exist_ok=True)
@@ -139,53 +185,8 @@ def launch_tor(conf):
  'LearnCircuitBuildTimeout': '0',
  'CircuitBuildTimeout': conf['general']['circuit_timeout'],
  })
- # This block of code reads additional torrc lines from the user's
- # config.ini so they can add arbitrary additional options.
- #
- # The user can't replace our options, only add to them. For example,
- # there's no way to remove 'SocksPort auto' (if it is still in
- # TORRC_STARTING_POINT). If you add a SocksPort in your config.ini, you'll
- # open two socks ports.
- #
- # As an example, maybe the user hates their HDD and wants to fill it with
- # debug logs, and wants to tell Tor to use only 1 CPU core.
- #
- # [tor]
- # extra_lines =
- # Log debug file /tmp/tor-debug.log
- # NumCPUs 1
- for line in conf['tor']['extra_lines'].split('\n'):
- # Remove leading and trailing whitespace, if any
- line = line.strip()
- # Ignore blank lines
- if len(line) < 1:
- continue
- # The way stem handles configuring Tor with a dictionary is the first
- # word is a key and the remaining words are the value.
- kv = line.split(None, 1)
- if len(kv) < 2:
- fail_hard('All torrc lines must have 2 or more words. "%s" has '
- 'fewer', line)
- key, value = kv
- log.info('Adding "%s %s" to torrc with which we are launching Tor',
- key, value)
- # It's really easy to add to the torrc if the key doesn't exist
- if key not in torrc:
- torrc.update({key: value})
- # But if it does, we have to make a list of values. For example, say
- # the user wants to add a SocksPort and we already have
- # 'SocksPort auto' in the torrc. We'll go from
- # torrc['SocksPort'] == 'auto'
- # to
- # torrc['SocksPort'] == ['auto', '9050']
- else:
- existing_val = torrc[key]
- if isinstance(existing_val, str):
- torrc.update({key: [existing_val, value]})
- else:
- assert isinstance(existing_val, list)
- existing_val.append(value)
- torrc.update({key: existing_val})
+
+ torrc = parse_user_torrc_config(torrc, conf['tor']['extra_lines'])
  # Finally launch Tor
  try:
  stem.process.launch_tor_with_config(

tests/unit/util/test_stem.py

@@ -0,0 +1,34 @@
+"""Unit tests for stem.py"""
+
+from sbws.util.stem import parse_user_torrc_config
+
+
+def test_parse_user_torrc_config_new_keyvalue_options_success():
+ config_torrc_extra_lines = """
+ Log debug file /tmp/tor-debug.log
+ NumCPUs 1
+ """
+ torrc_dict = parse_user_torrc_config({}, config_torrc_extra_lines)
+ assert torrc_dict == \
+ {'Log': 'debug file /tmp/tor-debug.log', 'NumCPUs': '1'}
+
+
+def test_parse_user_torrc_config_existing_keyvalue_options_fail(caplog):
+ torrc_dict = {'SocksPort': 'auto'}
+ config_torrc_extra_lines = """
+ SocksPort 9050
+ """
+ torrc_dict_new = parse_user_torrc_config(
+ torrc_dict, config_torrc_extra_lines)
+ # the new dictionary contains the existing key option and a list with both
+ # the existing value and the new value
+ assert torrc_dict_new != torrc_dict
+ assert torrc_dict_new == {'SocksPort': ['auto', '9050']}
+
+
+def test_parse_user_torrc_config_new_key_option_success():
+ config_torrc_extra_lines = """
+ LongLivedPorts
+ """
+ torrc_dict = parse_user_torrc_config({}, config_torrc_extra_lines)
+ assert torrc_dict == {'LongLivedPorts': None}