One of my favorite features of the Netlink specs is that they
make decoding structured extack a ton easier.
Implement pretty printing bad attribute names in YNL.
For example it will now say:
'bad-attr': '.header.flags'
rather than the useless:
'bad-attr-offs': 32
Proof:
$ ./cli.py --spec ethtool.yaml --do rings_get \
--json '{"header":{"dev-index":1, "flags":4}}'
Netlink error: Invalid argument
nl_len = 68 (52) nl_flags = 0x300 nl_type = 2
error: -22 extack: {'msg': 'reserved bit set',
'bad-attr': '.header.flags'}
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
---
tools/net/ynl/lib/ynl.py | 40 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 40 insertions(+)
diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py
index c16326495cb7..2ff3e6dbdbf6 100644
--- a/tools/net/ynl/lib/ynl.py
+++ b/tools/net/ynl/lib/ynl.py
@@ -400,6 +400,40 @@ genl_family_name_to_id = None
self._decode_enum(rsp, attr_spec)
return rsp
+ def _decode_extack_path(self, attrs, attr_set, offset, target):
+ for attr in attrs:
+ attr_spec = attr_set.attrs_by_val[attr.type]
+ if offset > target:
+ break
+ if offset == target:
+ return '.' + attr_spec.name
+
+ if offset + attr.full_len <= target:
+ offset += attr.full_len
+ continue
+ if attr_spec['type'] != 'nest':
+ raise Exception(f"Can't dive into {attr.type} ({attr_spec['name']}) for extack")
+ offset += 4
+ subpath = self._decode_extack_path(NlAttrs(attr.raw),
+ self.attr_sets[attr_spec['nested-attributes']],
+ offset, target)
+ if subpath is None:
+ return None
+ return '.' + attr_spec.name + subpath
+
+ return None
+
+ def _decode_extack(self, request, attr_space, extack):
+ if 'bad-attr-offs' not in extack:
+ return
+
+ genl_req = GenlMsg(NlMsg(request, 0, attr_space=attr_space))
+ path = self._decode_extack_path(genl_req.raw_attrs, attr_space,
+ 20, extack['bad-attr-offs'])
+ if path:
+ del extack['bad-attr-offs']
+ extack['bad-attr'] = path
+
def handle_ntf(self, nl_msg, genl_msg):
msg = dict()
if self.include_raw:
@@ -455,11 +489,17 @@ genl_family_name_to_id = None
reply = self.sock.recv(128 * 1024)
nms = NlMsgs(reply, attr_space=op.attr_set)
for nl_msg in nms:
+ if nl_msg.extack:
+ self._decode_extack(msg, op.attr_set, nl_msg.extack)
+
if nl_msg.error:
print("Netlink error:", os.strerror(-nl_msg.error))
print(nl_msg)
return
if nl_msg.done:
+ if nl_msg.extack:
+ print("Netlink warning:")
+ print(nl_msg)
done = True
break
--
2.39.1
