示例#1
0
 def get_paths(self, dst_ia, flags=(), flush=False):
     """Return a list of paths."""
     logging.debug("Paths requested for ISDAS=%s, flags=%s, flush=%s",
                   dst_ia, flags, flush)
     if flush:
         logging.info("Flushing PathDBs.")
         self._flush_path_dbs()
     if self.addr.isd_as == dst_ia or (self.addr.isd_as.any_as() == dst_ia
                                       and self.topology.is_core_as):
         # Either the destination is the local AS, or the destination is any
         # core AS in this ISD, and the local AS is in the core
         empty = SCIONPath()
         empty_meta = FwdPathMeta.from_values(empty, [], self.topology.mtu)
         return [empty_meta], SCIONDPathReplyError.OK
     paths = self.path_resolution(dst_ia, flags=flags)
     if not paths:
         key = dst_ia, flags
         with self.req_path_lock:
             if key not in self.requested_paths:
                 # No previous outstanding request
                 self.requested_paths[key] = threading.Event()
                 self._fetch_segments(key)
             e = self.requested_paths[key]
         if not e.wait(self.PATH_REQ_TOUT):
             logging.error("Query timed out for %s", dst_ia)
             return [], SCIONDPathReplyError.PS_TIMEOUT
         paths = self.path_resolution(dst_ia, flags=flags)
     error_code = (SCIONDPathReplyError.OK
                   if paths else SCIONDPathReplyError.NO_PATHS)
     return paths, error_code
示例#2
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def _join_peer(up_segment, down_segment, point, peer_revs):
    """
    Joins the supplied segments into a shortcut (peer) fullpath.

    :param list up_segment: `up` :any:`PathSegment`.
    :param list down_segment: `down` :any:`PathSegment`.
    :param tuple point: Indexes of peer point.
    :param RevCache peer_revs: Peering revocations.
    :returns: :any:`CrossOverPath`.
    """
    (up_index, down_index) = point

    up_iof, up_hofs, up_upstream_hof, up_mtu = \
        _copy_segment_shortcut(up_segment, up_index)
    down_iof, down_hofs, down_upstream_hof, down_mtu = \
        _copy_segment_shortcut(down_segment, down_index, up=False)
    up_iof.shortcut = down_iof.shortcut = True
    up_iof.peer = down_iof.peer = True
    path_metas = []
    for uph, dph, pm in _find_peer_hfs(up_segment.asm(up_index),
                                       down_segment.asm(down_index),
                                       peer_revs):
        um = min(up_mtu, pm)
        dm = min(down_mtu, pm)
        args = _shortcut_path_args(up_iof, up_hofs + [uph, up_upstream_hof],
                                   down_iof,
                                   [down_upstream_hof, dph] + down_hofs)
        path = SCIONPath.from_values(*args)
        if_list = _build_shortcut_interface_list(up_segment, up_index,
                                                 down_segment, down_index,
                                                 (uph, dph))
        mtu = _min_mtu(um, dm)
        path_meta = FwdPathMeta.from_values(path, if_list, mtu)
        path_metas.append(path_meta)
    return path_metas
示例#3
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def _join_xovr(up_segment, down_segment, point):
    """
    Joins the supplied segments into a shortcut (xovr) fullpath.

    :param list up_segment: `up` :any:`PathSegment`.
    :param list down_segment: `down` :any:`PathSegment`.
    :param tuple point: Indexes of xovr point.
    :returns: :any:`CrossOverPath`.
    """
    (up_index, down_index) = point

    up_iof, up_hofs, up_upstream_hof, up_mtu = \
        _copy_segment_shortcut(up_segment, up_index)
    down_iof, down_hofs, down_upstream_hof, down_mtu = \
        _copy_segment_shortcut(down_segment, down_index, up=False)

    up_iof.shortcut = down_iof.shortcut = True
    up_iof.peer = down_iof.peer = False
    up_hofs.append(up_upstream_hof)
    down_hofs.insert(0, down_upstream_hof)
    args = _shortcut_path_args(up_iof, up_hofs, down_iof, down_hofs)
    path = SCIONPath.from_values(*args)
    if_list = _build_shortcut_interface_list(up_segment, up_index,
                                             down_segment, down_index)
    mtu = _min_mtu(up_mtu, down_mtu)
    path_meta = FwdPathMeta.from_values(path, if_list, mtu)
    return [path_meta]
示例#4
0
文件: sciond.py 项目: MrShiyu/scion
 def get_paths(self, dst_ia, flags=(), flush=False):
     """Return a list of paths."""
     logging.debug("Paths requested for ISDAS=%s, flags=%s, flush=%s",
                   dst_ia, flags, flush)
     if flush:
         logging.info("Flushing PathDBs.")
         self._flush_path_dbs()
     if self.addr.isd_as == dst_ia or (
             self.addr.isd_as.any_as() == dst_ia and
             self.topology.is_core_as):
         # Either the destination is the local AS, or the destination is any
         # core AS in this ISD, and the local AS is in the core
         empty = SCIONPath()
         empty_meta = FwdPathMeta.from_values(empty, [], self.topology.mtu)
         return [empty_meta], SCIONDPathReplyError.OK
     deadline = SCIONTime.get_time() + self.PATH_REQ_TOUT
     e = threading.Event()
     self.requests.put(((dst_ia, flags), e))
     if not self._wait_for_events([e], deadline):
         logging.error("Query timed out for %s", dst_ia)
         return [], SCIONDPathReplyError.PS_TIMEOUT
     paths = self.path_resolution(dst_ia, flags=flags)
     error_code = (SCIONDPathReplyError.OK if paths
                   else SCIONDPathReplyError.NO_PATHS)
     return paths, error_code
示例#5
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 def test_xovr(self, build_list, path_args, copy_segment):
     up_segment, down_segment, point, exp_time = self._setup(path_args, copy_segment)
     path_meta = FwdPathMeta.from_values(SCIONPath(), [], 0, exp_time)
     ntools.eq_(
         path_combinator._join_xovr(up_segment, down_segment, point)[0],
         path_meta)
     copy_segment.assert_any_call(up_segment, 1)
     copy_segment.assert_any_call(down_segment, 2, cons_dir=True)
     ntools.eq_(build_list.call_count, 1)
示例#6
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 def test_peer(self, find_peers, build_list, path_args, copy_segment):
     up_segment, down_segment, point, exp_time = self._setup(path_args, copy_segment)
     find_peers.return_value = [("uph1", "dph1", 1500),
                                ("uph2", "dph2", 1500)]
     peer_revs = create_mock()
     path_meta = FwdPathMeta.from_values(SCIONPath(), [], 0, exp_time)
     ntools.eq_(path_combinator._join_peer(
         up_segment, down_segment, point, peer_revs)[0], path_meta)
     copy_segment.assert_any_call(up_segment, 1)
     copy_segment.assert_any_call(down_segment, 2, cons_dir=True)
     ntools.eq_(build_list.call_count, 2)
示例#7
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 def get_paths(self, dst_ia, flags=(), flush=False):
     """Return a list of paths."""
     logging.debug("Paths requested for ISDAS=%s, flags=%s, flush=%s",
                   dst_ia, flags, flush)
     if flush:
         logging.info("Flushing PathDBs.")
         self._flush_path_dbs()
     if self.addr.isd_as == dst_ia or (self.addr.isd_as.any_as() == dst_ia
                                       and self.topology.is_core_as):
         # Either the destination is the local AS, or the destination is any
         # core AS in this ISD, and the local AS is in the core
         empty = SCIONPath()
         exp_time = int(time.time()) + self.EMPTY_PATH_TTL
         empty_meta = FwdPathMeta.from_values(empty, [], self.topology.mtu,
                                              exp_time)
         return [empty_meta], SCIONDPathReplyError.OK
     paths = self.path_resolution(dst_ia, flags=flags)
     if not paths:
         key = dst_ia, flags
         with self.req_path_lock:
             r = self.requested_paths.get(key)
             if r is None:
                 # No previous outstanding request
                 req = PathSegmentReq.from_values(self.addr.isd_as,
                                                  dst_ia,
                                                  flags=flags)
                 r = RequestState(req.copy())
                 self.requested_paths[key] = r
                 self._fetch_segments(req)
         # Wait until event gets set.
         timeout = not r.e.wait(PATH_REQ_TOUT)
         with self.req_path_lock:
             if timeout:
                 r.done()
             if key in self.requested_paths:
                 del self.requested_paths[key]
         if timeout:
             logging.error("Query timed out for %s", dst_ia)
             return [], SCIONDPathReplyError.PS_TIMEOUT
         # Check if we can fulfill the path request.
         paths = self.path_resolution(dst_ia, flags=flags)
         if not paths:
             logging.error("No paths found for %s", dst_ia)
             return [], SCIONDPathReplyError.NO_PATHS
     return paths, SCIONDPathReplyError.OK
示例#8
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def tuples_to_full_paths(tuples):
    """
    For a set of tuples of possible end-to-end path [format is:
    (up_seg, core_seg, down_seg)], return a list of fullpaths.
    """
    res = []
    for up_segment, core_segment, down_segment in tuples:
        if not up_segment and not core_segment and not down_segment:
            continue
        if not _check_connected(up_segment, core_segment, down_segment):
            continue

        up_iof, up_hofs, up_mtu, up_exp = _copy_segment(
            up_segment, False, (core_segment or down_segment))
        core_iof, core_hofs, core_mtu, core_exp = _copy_segment(
            core_segment, up_segment, down_segment)
        down_iof, down_hofs, down_mtu, down_exp = _copy_segment(
            down_segment, (up_segment or core_segment), False, cons_dir=True)
        args = []
        for iof, hofs in [(up_iof, up_hofs), (core_iof, core_hofs),
                          (down_iof, down_hofs)]:
            if iof:
                args.extend([iof, hofs])
        path = SCIONPath.from_values(*args)
        if up_segment:
            up_core = list(reversed(list(up_segment.iter_asms())))
        else:
            up_core = []
        if core_segment:
            up_core += list(reversed(list(core_segment.iter_asms())))
        if_list = _build_interface_list(up_core)
        if down_segment:
            down_core = list(down_segment.iter_asms())
        else:
            down_core = []
        if_list += _build_interface_list(down_core, cons_dir=True)
        mtu = _min_mtu(up_mtu, core_mtu, down_mtu)
        exp = min(up_exp, core_exp, down_exp)
        path_meta = FwdPathMeta.from_values(path, if_list, mtu, exp)
        res.append(path_meta)
    return res