From 690252f19f0e486abb8590b3a7a03d4e065d93d4 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Thu, 25 Aug 2022 20:09:31 -0700 Subject: netlink: add support for ext_ack missing attributes There is currently no way to report via extack in a structured way that an attribute is missing. This leads to families resorting to string messages. Add a pair of attributes - @offset and @type for machine-readable way of reporting missing attributes. The @offset points to the nest which should have contained the attribute, @type is the expected nla_type. The offset will be skipped if the attribute is missing at the message level rather than inside a nest. User space should be able to figure out which attribute enum (AKA attribute space AKA attribute set) the nest pointed to by @offset is using. Reviewed-by: Johannes Berg Signed-off-by: Jakub Kicinski Signed-off-by: Paolo Abeni --- include/uapi/linux/netlink.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/netlink.h b/include/uapi/linux/netlink.h index e0ab261ceca2..e0689dbd2cde 100644 --- a/include/uapi/linux/netlink.h +++ b/include/uapi/linux/netlink.h @@ -140,6 +140,10 @@ struct nlmsgerr { * be used - in the success case - to identify a created * object or operation or similar (binary) * @NLMSGERR_ATTR_POLICY: policy for a rejected attribute + * @NLMSGERR_ATTR_MISS_TYPE: type of a missing required attribute, + * %NLMSGERR_ATTR_MISS_NEST will not be present if the attribute was + * missing at the message level + * @NLMSGERR_ATTR_MISS_NEST: offset of the nest where attribute was missing * @__NLMSGERR_ATTR_MAX: number of attributes * @NLMSGERR_ATTR_MAX: highest attribute number */ @@ -149,6 +153,8 @@ enum nlmsgerr_attrs { NLMSGERR_ATTR_OFFS, NLMSGERR_ATTR_COOKIE, NLMSGERR_ATTR_POLICY, + NLMSGERR_ATTR_MISS_TYPE, + NLMSGERR_ATTR_MISS_NEST, __NLMSGERR_ATTR_MAX, NLMSGERR_ATTR_MAX = __NLMSGERR_ATTR_MAX - 1 -- cgit v1.2.3