def filter(self, func, cascade=True, **vars) -> 'PacketFilter':
"""
Create a new PacketFilter based on this packet filter with given filter func
:param func: a callable that returns a bool (e.x. lambda p: xxx) or a filter string
:param cascade: True if calling next in the new filter will also set index for this filter, False otherwise
:param vars: variables for filter string
:return: a new PacketFilter
"""
print('\n>>> filtering in range %s~%s%s:' %
(self._index, self._stop_index, "<end>" if self._stop_index == len(self._pkts) else "<stop>"),
file=sys.stderr)
func = make_filter_func(func, **vars)
self._check_type_ok()
return PacketFilter(self._pkts,
self._index,
self._stop_index,
filter_func=lambda p: self._filter_func(p) and func(p),
parent=self if cascade else None)
def verify(self, func: Union[str, Callable], **vars) -> bool:
print("\n>>> verifying packet:", file=sys.stderr, flush=False)
func = make_filter_func(func, **vars)
ok = func(self)
print("\t=> %s" % ok, file=sys.stderr)
return ok