The main tasks of the Service Discovery Protocol are communicating the availability of functional entities called services in the in-vehicle communication as well as controlling the send behavior of event messages. This allows sending only event messages to receivers requiring them (Publish/Subscribe). The solution described here is also known as SOME/IP-SD (Scalable service-Oriented MiddlewarE over IP - Service Discovery).
This page hosts a formal specification of AUTOSAR SOME/IP Service Discovery using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
# type: ignore
import kaitaistruct
from kaitaistruct import ReadWriteKaitaiStruct, KaitaiStream, BytesIO
import some_ip_sd_options
import some_ip_sd_entries
if getattr(kaitaistruct, 'API_VERSION', (0, 9)) < (0, 11):
raise Exception("Incompatible Kaitai Struct Python API: 0.11 or later is required, but you have %s" % (kaitaistruct.__version__))
class SomeIpSd(ReadWriteKaitaiStruct):
"""The main tasks of the Service Discovery Protocol are communicating the
availability of functional entities called services in the in-vehicle
communication as well as controlling the send behavior of event messages.
This allows sending only event messages to receivers requiring them (Publish/Subscribe).
The solution described here is also known as SOME/IP-SD
(Scalable service-Oriented MiddlewarE over IP - Service Discovery).
.. seealso::
Source - https://www.autosar.org/fileadmin/standards/foundation/19-11/AUTOSAR_PRS_SOMEIPServiceDiscoveryProtocol.pdf
"""
def __init__(self, _io=None, _parent=None, _root=None):
super(SomeIpSd, self).__init__(_io)
self._parent = _parent
self._root = _root or self
def _read(self):
self.flags = SomeIpSd.SdFlags(self._io, self, self._root)
self.flags._read()
self.reserved = self._io.read_bytes(3)
self.len_entries = self._io.read_u4be()
self._raw_entries = self._io.read_bytes(self.len_entries)
_io__raw_entries = KaitaiStream(BytesIO(self._raw_entries))
self.entries = some_ip_sd_entries.SomeIpSdEntries(_io__raw_entries)
self.entries._read()
self.len_options = self._io.read_u4be()
self._raw_options = self._io.read_bytes(self.len_options)
_io__raw_options = KaitaiStream(BytesIO(self._raw_options))
self.options = some_ip_sd_options.SomeIpSdOptions(_io__raw_options)
self.options._read()
self._dirty = False
def _fetch_instances(self):
pass
self.flags._fetch_instances()
self.entries._fetch_instances()
self.options._fetch_instances()
def _write__seq(self, io=None):
super(SomeIpSd, self)._write__seq(io)
self.flags._write__seq(self._io)
self._io.write_bytes(self.reserved)
self._io.write_u4be(self.len_entries)
_io__raw_entries = KaitaiStream(BytesIO(bytearray(self.len_entries)))
self._io.add_child_stream(_io__raw_entries)
_pos2 = self._io.pos()
self._io.seek(self._io.pos() + (self.len_entries))
def handler(parent, _io__raw_entries=_io__raw_entries):
self._raw_entries = _io__raw_entries.to_byte_array()
if len(self._raw_entries) != self.len_entries:
raise kaitaistruct.ConsistencyError(u"raw(entries)", self.len_entries, len(self._raw_entries))
parent.write_bytes(self._raw_entries)
_io__raw_entries.write_back_handler = KaitaiStream.WriteBackHandler(_pos2, handler)
self.entries._write__seq(_io__raw_entries)
self._io.write_u4be(self.len_options)
_io__raw_options = KaitaiStream(BytesIO(bytearray(self.len_options)))
self._io.add_child_stream(_io__raw_options)
_pos2 = self._io.pos()
self._io.seek(self._io.pos() + (self.len_options))
def handler(parent, _io__raw_options=_io__raw_options):
self._raw_options = _io__raw_options.to_byte_array()
if len(self._raw_options) != self.len_options:
raise kaitaistruct.ConsistencyError(u"raw(options)", self.len_options, len(self._raw_options))
parent.write_bytes(self._raw_options)
_io__raw_options.write_back_handler = KaitaiStream.WriteBackHandler(_pos2, handler)
self.options._write__seq(_io__raw_options)
def _check(self):
if self.flags._root != self._root:
raise kaitaistruct.ConsistencyError(u"flags", self._root, self.flags._root)
if self.flags._parent != self:
raise kaitaistruct.ConsistencyError(u"flags", self, self.flags._parent)
if len(self.reserved) != 3:
raise kaitaistruct.ConsistencyError(u"reserved", 3, len(self.reserved))
self._dirty = False
class SdFlags(ReadWriteKaitaiStruct):
"""
.. seealso::
AUTOSAR_PRS_SOMEIPServiceDiscoveryProtocol.pdf - Figure 4.3
"""
def __init__(self, _io=None, _parent=None, _root=None):
super(SomeIpSd.SdFlags, self).__init__(_io)
self._parent = _parent
self._root = _root
def _read(self):
self.reboot = self._io.read_bits_int_be(1) != 0
self.unicast = self._io.read_bits_int_be(1) != 0
self.initial_data = self._io.read_bits_int_be(1) != 0
self.reserved = self._io.read_bits_int_be(5)
self._dirty = False
def _fetch_instances(self):
pass
def _write__seq(self, io=None):
super(SomeIpSd.SdFlags, self)._write__seq(io)
self._io.write_bits_int_be(1, int(self.reboot))
self._io.write_bits_int_be(1, int(self.unicast))
self._io.write_bits_int_be(1, int(self.initial_data))
self._io.write_bits_int_be(5, self.reserved)
def _check(self):
self._dirty = False