tools: ynl: introduce option to process unknown attributes or types

In case the kernel sends message back containing attribute not defined
in family spec, following exception is raised to the user:

$ sudo ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/devlink.yaml --do trap-get --json '{"bus-name": "netdevsim", "dev-name": "netdevsim1", "trap-name": "source_mac_is_multicast"}'
Traceback (most recent call last):
  File "/home/jiri/work/linux/tools/net/ynl/lib/ynl.py", line 521, in _decode
    attr_spec = attr_space.attrs_by_val[attr.type]
                ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^
KeyError: 132

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/jiri/work/linux/./tools/net/ynl/cli.py", line 61, in <module>
    main()
  File "/home/jiri/work/linux/./tools/net/ynl/cli.py", line 49, in main
    reply = ynl.do(args.do, attrs, args.flags)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jiri/work/linux/tools/net/ynl/lib/ynl.py", line 731, in do
    return self._op(method, vals, flags)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jiri/work/linux/tools/net/ynl/lib/ynl.py", line 719, in _op
    rsp_msg = self._decode(decoded.raw_attrs, op.attr_set.name)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jiri/work/linux/tools/net/ynl/lib/ynl.py", line 525, in _decode
    raise Exception(f"Space '{space}' has no attribute with value '{attr.type}'")
Exception: Space 'devlink' has no attribute with value '132'

Introduce a command line option "process-unknown" and pass it down to
YnlFamily class constructor to allow user to process unknown
attributes and types and print them as binaries.

$ sudo ./tools/net/ynl/cli.py --spec Documentation/netlink/specs/devlink.yaml --do trap-get --json '{"bus-name": "netdevsim", "dev-name": "netdevsim1", "trap-name": "source_mac_is_multicast"}' --process-unknown
{'UnknownAttr(129)': {'UnknownAttr(0)': b'\x00\x00\x00\x00\x00\x00\x00\x00',
                      'UnknownAttr(1)': b'\x00\x00\x00\x00\x00\x00\x00\x00',
                      'UnknownAttr(2)': b'\x0e\x00\x00\x00\x00\x00\x00\x00'},
 'UnknownAttr(132)': b'\x00',
 'UnknownAttr(133)': b'',
 'UnknownAttr(134)': {'UnknownAttr(0)': b''},
 'bus-name': 'netdevsim',
 'dev-name': 'netdevsim1',
 'trap-action': 'drop',
 'trap-group-name': 'l2_drops',
 'trap-name': 'source_mac_is_multicast'}

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20231027092525.956172-1-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Jiri Pirko 2023-10-27 11:25:25 +02:00 committed by Jakub Kicinski
parent ff672b9ffe
commit d96e48a3d5
2 changed files with 39 additions and 12 deletions

View file

@ -27,6 +27,7 @@ def main():
const=Netlink.NLM_F_CREATE)
parser.add_argument('--append', dest='flags', action='append_const',
const=Netlink.NLM_F_APPEND)
parser.add_argument('--process-unknown', action=argparse.BooleanOptionalAction)
args = parser.parse_args()
if args.no_schema:
@ -36,7 +37,7 @@ def main():
if args.json_text:
attrs = json.loads(args.json_text)
ynl = YnlFamily(args.spec, args.schema)
ynl = YnlFamily(args.spec, args.schema, args.process_unknown)
if args.ntf:
ynl.ntf_subscribe(args.ntf)

View file

@ -100,6 +100,7 @@ class NlAttr:
def __init__(self, raw, offset):
self._len, self._type = struct.unpack("HH", raw[offset:offset + 4])
self.type = self._type & ~Netlink.NLA_TYPE_MASK
self.is_nest = self._type & Netlink.NLA_F_NESTED
self.payload_len = self._len
self.full_len = (self.payload_len + 3) & ~3
self.raw = raw[offset + 4:offset + self.payload_len]
@ -411,10 +412,11 @@ class GenlProtocol(NetlinkProtocol):
class YnlFamily(SpecFamily):
def __init__(self, def_path, schema=None):
def __init__(self, def_path, schema=None, process_unknown=False):
super().__init__(def_path, schema)
self.include_raw = False
self.process_unknown = process_unknown
try:
if self.proto == "netlink-raw":
@ -526,14 +528,41 @@ class YnlFamily(SpecFamily):
decoded.append({ item.type: subattrs })
return decoded
def _decode_unknown(self, attr):
if attr.is_nest:
return self._decode(NlAttrs(attr.raw), None)
else:
return attr.as_bin()
def _rsp_add(self, rsp, name, is_multi, decoded):
if is_multi == None:
if name in rsp and type(rsp[name]) is not list:
rsp[name] = [rsp[name]]
is_multi = True
else:
is_multi = False
if not is_multi:
rsp[name] = decoded
elif name in rsp:
rsp[name].append(decoded)
else:
rsp[name] = [decoded]
def _decode(self, attrs, space):
attr_space = self.attr_sets[space]
if space:
attr_space = self.attr_sets[space]
rsp = dict()
for attr in attrs:
try:
attr_spec = attr_space.attrs_by_val[attr.type]
except KeyError:
raise Exception(f"Space '{space}' has no attribute with value '{attr.type}'")
except (KeyError, UnboundLocalError):
if not self.process_unknown:
raise Exception(f"Space '{space}' has no attribute with value '{attr.type}'")
attr_name = f"UnknownAttr({attr.type})"
self._rsp_add(rsp, attr_name, None, self._decode_unknown(attr))
continue
if attr_spec["type"] == 'nest':
subdict = self._decode(NlAttrs(attr.raw), attr_spec['nested-attributes'])
decoded = subdict
@ -558,14 +587,11 @@ class YnlFamily(SpecFamily):
selector = self._decode_enum(selector, attr_spec)
decoded = {"value": value, "selector": selector}
else:
raise Exception(f'Unknown {attr_spec["type"]} with name {attr_spec["name"]}')
if not self.process_unknown:
raise Exception(f'Unknown {attr_spec["type"]} with name {attr_spec["name"]}')
decoded = self._decode_unknown(attr)
if not attr_spec.is_multi:
rsp[attr_spec['name']] = decoded
elif attr_spec.name in rsp:
rsp[attr_spec.name].append(decoded)
else:
rsp[attr_spec.name] = [decoded]
self._rsp_add(rsp, attr_spec["name"], attr_spec.is_multi, decoded)
return rsp