On Wed, Mar 9, 2016 at 9:05 AM, Samuel Gauthier
<samuel.gauth...@6wind.com> wrote:
> When we want to change a flow using netlink, we have to identify it to
> be able to perform a lookup. Both the flow key and unique flow ID
> (ufid) are valid identifiers, but we always have to specify the flow
> key in the netlink message. When both attributes are there, the ufid
> is used.
>
> This commit allows to use the ufid without having to provide the flow
> key, as it is already done in the netlink 'flow get' and 'flow del'
> path.
>
> Signed-off-by: Samuel Gauthier <samuel.gauth...@6wind.com>
> ---
> net/openvswitch/datapath.c | 21 ++++++++++-----------
> 1 file changed, 10 insertions(+), 11 deletions(-)
>
> diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
> index deadfdab1bc3..06f15143cf2a 100644
> --- a/net/openvswitch/datapath.c
> +++ b/net/openvswitch/datapath.c
> @@ -1100,21 +1100,20 @@ static int ovs_flow_cmd_set(struct sk_buff *skb,
> struct genl_info *info)
> struct sw_flow_match match;
> struct sw_flow_id sfid;
> u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
> - int error;
> + int error = 0;
> bool log = !a[OVS_FLOW_ATTR_PROBE];
> bool ufid_present;
>
> - /* Extract key. */
> - error = -EINVAL;
> - if (!a[OVS_FLOW_ATTR_KEY]) {
> - OVS_NLERR(log, "Flow key attribute not present in set flow.");
> - goto error;
> - }
> -
> ufid_present = ovs_nla_get_ufid(&sfid, a[OVS_FLOW_ATTR_UFID], log);
> - ovs_match_init(&match, &key, &mask);
> - error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
> - a[OVS_FLOW_ATTR_MASK], log);
> + if (a[OVS_FLOW_ATTR_KEY]) {
> + ovs_match_init(&match, &key, NULL);
> + error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
> + NULL, log);
> + } else if (!ufid_present) {
> + OVS_NLERR(log,
> + "Flow set message rejected, Key attribute
> missing.");
> + error = -EINVAL;
> + }
Set command sets new action for given flow. The action validation
depends on the flow key and mask. so userspace needs to provide the
key and mask.
