def parse_action(self, tokens):
if not tokens:
self._parser_state.error('missing action')
action_token = tokens.pop(0)
if action_token.type == 'ACTION':
if action_token.value == 'allow':
return bpf.Allow()
if action_token.value == 'kill':
return self._kill_action
if action_token.value == 'kill-process':
return bpf.KillProcess()
if action_token.value == 'kill-thread':
return bpf.KillThread()
if action_token.value == 'trap':
return bpf.Trap()
if action_token.value == 'trace':
return bpf.Trace()
if action_token.value == 'log':
return bpf.Log()
elif action_token.type == 'NUMERIC_CONSTANT':
constant = self._parse_single_constant(action_token)
if constant == 1:
return bpf.Allow()
elif action_token.type == 'RETURN':
if not tokens:
self._parser_state.error('missing return value')
return bpf.ReturnErrno(self._parse_single_constant(tokens.pop(0)))
return self._parser_state.error('invalid action', token=action_token)
def test_parse_filter(self):
"""Accept valid filters."""
self.assertEqual(
self.parser.parse_filter(self._tokenize('arg0 == 0')), [
parser.Filter([[parser.Atom(0, '==', 0)]], bpf.Allow()),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('kill-process')), [
parser.Filter(None, bpf.KillProcess()),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('kill-thread')), [
parser.Filter(None, bpf.KillThread()),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('trap')), [
parser.Filter(None, bpf.Trap()),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('return ENOSYS')), [
parser.Filter(None,
bpf.ReturnErrno(self.arch.constants['ENOSYS'])),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('trace')), [
parser.Filter(None, bpf.Trace()),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('user-notify')), [
parser.Filter(None, bpf.UserNotify()),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('log')), [
parser.Filter(None, bpf.Log()),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('allow')), [
parser.Filter(None, bpf.Allow()),
])
self.assertEqual(
self.parser.parse_filter(self._tokenize('1')), [
parser.Filter(None, bpf.Allow()),
])
self.assertEqual(
self.parser.parse_filter(
self._tokenize(
'{ arg0 == 0, arg0 == 1; return ENOSYS, trap }')),
[
parser.Filter([[parser.Atom(0, '==', 0)]], bpf.Allow()),
parser.Filter([[parser.Atom(0, '==', 1)]],
bpf.ReturnErrno(self.arch.constants['ENOSYS'])),
parser.Filter(None, bpf.Trap()),
])
def parse_action(self, tokens):
if not tokens:
self._parser_state.error('missing action')
action_token = tokens.pop(0)
# denylist policies must specify a return for every line.
if self._denylist:
if action_token.type != 'RETURN':
self._parser_state.error('invalid denylist policy')
if action_token.type == 'ACTION':
if action_token.value == 'allow':
return bpf.Allow()
if action_token.value == 'kill':
return self._kill_action
if action_token.value == 'kill-process':
return bpf.KillProcess()
if action_token.value == 'kill-thread':
return bpf.KillThread()
if action_token.value == 'trap':
return bpf.Trap()
if action_token.value == 'trace':
return bpf.Trace()
if action_token.value == 'user-notify':
return bpf.UserNotify()
if action_token.value == 'log':
return bpf.Log()
elif action_token.type == 'NUMERIC_CONSTANT':
constant = self._parse_single_constant(action_token)
if constant == 1:
return bpf.Allow()
elif action_token.type == 'RETURN':
if not tokens:
self._parser_state.error('missing return value')
if self._ret_log:
tokens.pop(0)
return bpf.Log()
else:
return bpf.ReturnErrno(
self._parse_single_constant(tokens.pop(0)))
return self._parser_state.error('invalid action', token=action_token)