class SignedCtrlPayload(Cerealizable):
NAME = "SignedCtrlPayload"
P_CLS = P.SignedCtrlPld
def __init__(self, p): # pragma: no cover
super().__init__(p)
self.psign = ProtoSign(self.p.sign)
@classmethod
def from_raw(cls, raw):
data = Raw(raw, "%s.from_raw" % cls.NAME)
plen = struct.unpack("!I", data.pop(4))[0]
if len(data) != plen:
raise SCIONParseError(
"Payload length mismatch. Expected: %s Actual: %s" %
(plen, len(data)))
try:
p = cls.P_CLS.from_bytes_packed(data.pop()).as_builder()
except capnp.lib.capnp.KjException as e:
raise SCIONParseError("Unable to parse %s capnp message: %s" %
(cls.NAME, e)) from None
return cls.from_proto(p)
@classmethod
def from_values(cls, cpld_raw, sign=None):
if not sign:
sign = ProtoSign.from_values(ProtoSignType.NONE, b"")
return cls(cls.P_CLS.new_message(blob=cpld_raw, sign=sign.p))
def sign(self, key):
return self.psign.sign(key, self.p.blob)
def verify(self, key):
return self.psign.verify(key, self.p.blob)
def pack(self): # pragma: no cover
raw = self.proto().to_bytes_packed()
return struct.pack("!I", len(raw)) + raw
def pld(self):
return CtrlPayload.from_raw(self.p.blob)
def sign(self, key): # pragma: no cover
assert len(self.p.asEntries) > 0, "No ASMarkings to sign"
s = ProtoSign(self.p.asEntries[-1].sign)
s.sign(key, self._sig_input())