def _handle_o_call(self, sig, packet, bit_offset):
op = sig[0]
args = sig[1]
if op == 'tLookup':
resp = packet.metadata[args[0]]
req = packet.metadata[args[1]]
if self.table:
resp.reset_values()
self.table.lookup(req, resp)
elif op == 'hInsert':
length = args[0] if len(args) > 0 else len(self.header)
packet.insert(length, bit_offset)
elif op == 'hRemove':
length = args[0] if len(args) > 0 else len(self.header)
packet.remove(length, bit_offset)
elif op == 'tInsert':
mask = args[2] if len(args) > 2 else None
if self.table:
self.table.add_entry(args[0], args[1], mask)
elif op == 'tRemove':
mask = args[2] if len(args) > 2 else None
if self.table:
self.table.remove_entry(args[0], args[1], mask)
else:
raise BIRError("unknown build-in function: {}".format(op))
def _get_processor(self, name):
if name in self.bir_control_flows.keys():
return self.bir_control_flows[name]
elif name in self.bir_other_processors.keys():
return self.bir_other_processors[name]
else:
raise BIRError("unknown processor: {}".format(name))
def _get_basic_block(self, packet, bit_offset):
for cond in self.basic_block:
if isinstance(cond, str):
return cond
elif self.bir_parser.eval_cond(cond[0], self.header, packet,
bit_offset):
return cond[1]
raise BIRError("didn't find basic_block!")
def _handle_m_call(self, sig, packet, bit_offset):
if len(sig[1]) != 2:
raise BIRError("M instructions require 2 arguments")
op = sig[0]
data_out = sig[1][0]
data_in = sig[1][1]
if op not in self.other_modules.keys():
raise BIRError("cannot find other_module: {}".format(sig[0]))
module = self.other_modules[op]
if data_out:
data_out = packet.metadata[data_out]
if data_in:
# TODO: to ensure correctness, the data_in should be a copy of the
# metadata instance.
data_in = packet.metadata[data_in]
module(data_in, data_out)
def process(self, packet, bit_offset):
for inst in self.instructions:
if inst[0] == 'V':
self._handle_v_call(inst[1:], packet, bit_offset)
elif inst[0] == 'O':
self._handle_o_call(inst[1:], packet, bit_offset)
elif inst[0] == 'M':
self._handle_m_call(inst[1:], packet, bit_offset)
else:
raise BIRError("unknown instruction type: {}".format(inst[0]))
def _get_offset(self, packet, bit_offset):
for cond in self.offset:
if isinstance(cond, str) or isinstance(cond, int):
return self.bir_parser.eval_inst(cond, self.header, packet,
bit_offset)
elif self.bir_parser.eval_cond(cond[0], self.header, packet,
bit_offset):
return self.bir_parser.eval_inst(cond[1], self.header, packet,
bit_offset)
raise BIRError("didn't find offset!")
def run(self):
msg = "Processor {}: does not implement run()".format(self.name)
raise BIRError(msg)
def process(self, packet, bit_offset=0):
msg = "Processor {}: does not implement process()".format(self.name)
raise BIRError(msg)