diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2017-04-12 14:34:06 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-04-13 13:58:21 -0400 |
| commit | ba0dc5f6e0ba5a5d2f575bcdb35e5d1960cf7c04 (patch) | |
| tree | 67f74587529492b36ee1566352d961f245efa45c /net | |
| parent | 7ab606d1609dd6dfeae9c8ad0a8a4e051d831e46 (diff) | |
netlink: allow sending extended ACK with cookie on success
Now that we have extended error reporting and a new message format for
netlink ACK messages, also extend this to be able to return arbitrary
cookie data on success.
This will allow, for example, nl80211 to not send an extra message for
cookies identifying newly created objects, but return those directly
in the ACK message.
The cookie data size is currently limited to 20 bytes (since Jamal
talked about using SHA1 for identifiers.)
Thanks to Jamal Hadi Salim for bringing up this idea during the
discussions.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netlink/af_netlink.c | 33 |
1 files changed, 22 insertions, 11 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index c1564768000e..ee841f00a6ec 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -2311,6 +2311,10 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err, } } else { flags |= NLM_F_CAPPED; + + if (nlk->flags & NETLINK_F_EXT_ACK && + extack && extack->cookie_len) + tlvlen += nla_total_size(extack->cookie_len); } if (tlvlen) @@ -2337,17 +2341,24 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err, errmsg->error = err; memcpy(&errmsg->msg, nlh, payload > sizeof(*errmsg) ? nlh->nlmsg_len : sizeof(*nlh)); - if (err && nlk->flags & NETLINK_F_EXT_ACK && extack) { - if (extack->_msg) - WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG, - extack->_msg)); - if (extack->bad_attr && - !WARN_ON((u8 *)extack->bad_attr < in_skb->data || - (u8 *)extack->bad_attr >= in_skb->data + - in_skb->len)) - WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS, - (u8 *)extack->bad_attr - - in_skb->data)); + if (nlk->flags & NETLINK_F_EXT_ACK && extack) { + if (err) { + if (extack->_msg) + WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG, + extack->_msg)); + if (extack->bad_attr && + !WARN_ON((u8 *)extack->bad_attr < in_skb->data || + (u8 *)extack->bad_attr >= in_skb->data + + in_skb->len)) + WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS, + (u8 *)extack->bad_attr - + in_skb->data)); + } else { + if (extack->cookie_len) + WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE, + extack->cookie_len, + extack->cookie)); + } } nlmsg_end(skb, rep); |