def handle_socks_args(self, args):
"""
Receive arguments `args' passed over a SOCKS connection.
The SOCKS authentication mechanism is (ab)used to pass arguments to
pluggable transports. This method receives these arguments and parses
them. As argument, we only expect a UniformDH shared secret.
"""
log.debug("Received the following arguments over SOCKS: %s." % args)
if len(args) != 1:
raise base.SOCKSArgsError("Too many SOCKS arguments "
"(expected 1 but got %d)." % len(args))
# The ScrambleSuit specification defines that the shared secret is
# called "password".
if not args[0].startswith("password="******"The SOCKS argument must start with "
"`password='******'=')[1].strip()))
except TypeError as error:
log.error(error.message)
raise base.PluggableTransportError("Given password '%s' is not " \
"valid Base32! Run 'generate_password.py' to generate " \
"a good password." % args[0].split('=')[1].strip())
rawLength = len(self.uniformDHSecret)
if rawLength != const.SHARED_SECRET_LENGTH:
raise base.PluggableTransportError(
"The UniformDH password "
"must be %d bytes in length but %d bytes are given." %
(const.SHARED_SECRET_LENGTH, rawLength))
self.uniformdh = uniformdh.new(self.uniformDHSecret, self.weAreServer)
def handle_socks_args(self, args):
log.debug("obfs2: Got '%s' as SOCKS arguments." % args)
# A shared secret might already be set if obfsproxy is in
# external-mode and both a cli shared-secret was specified
# _and_ a SOCKS per-connection shared secret.
if self.shared_secret:
log.notice("obfs2: Hm. Weird configuration. A shared secret "
"was specified twice. I will keep the one "
"supplied by the SOCKS arguments.")
if len(args) != 1:
err_msg = "obfs2: Too many SOCKS arguments (%d) (%s)" % (len(args), str(args))
log.warning(err_msg)
raise base.SOCKSArgsError(err_msg)
if not args[0].startswith("shared-secret="):
err_msg = "obfs2: SOCKS arg is not correctly formatted (%s)" % args[0]
log.warning(err_msg)
raise base.SOCKSArgsError(err_msg)
self.shared_secret = args[0][14:]