Re: [RFC PATCH net-next 01/16] bridge: Add MAC Authentication Bypass (MAB) support

[netdev@xxxxxxxxxxxxxxxxxxxx]

On 2022-10-25 12:00, Ido Schimmel wrote:
> diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
> index 5aeb3646e74c..bbc82c70b091 100644
> --- a/net/bridge/br_netlink.c
> +++ b/net/bridge/br_netlink.c
> @@ -188,6 +188,7 @@ static inline size_t br_port_info_size(void)
>  		+ nla_total_size(1)	/* IFLA_BRPORT_NEIGH_SUPPRESS */
>  		+ nla_total_size(1)	/* IFLA_BRPORT_ISOLATED */
>  		+ nla_total_size(1)	/* IFLA_BRPORT_LOCKED */
> +		+ nla_total_size(1)	/* IFLA_BRPORT_MAB */
>  		+ nla_total_size(sizeof(struct ifla_bridge_id))	/* 
> IFLA_BRPORT_ROOT_ID */
>  		+ nla_total_size(sizeof(struct ifla_bridge_id))	/* 
> IFLA_BRPORT_BRIDGE_ID */
>  		+ nla_total_size(sizeof(u16))	/* IFLA_BRPORT_DESIGNATED_PORT */
> @@ -274,7 +275,8 @@ static int br_port_fill_attrs(struct sk_buff *skb,
>  	    nla_put_u8(skb, IFLA_BRPORT_MRP_IN_OPEN,
>  		       !!(p->flags & BR_MRP_LOST_IN_CONT)) ||
>  	    nla_put_u8(skb, IFLA_BRPORT_ISOLATED, !!(p->flags & BR_ISOLATED)) 
> ||
> -	    nla_put_u8(skb, IFLA_BRPORT_LOCKED, !!(p->flags & 
> BR_PORT_LOCKED)))
> +	    nla_put_u8(skb, IFLA_BRPORT_LOCKED, !!(p->flags & 
> BR_PORT_LOCKED)) ||
> +	    nla_put_u8(skb, IFLA_BRPORT_MAB, !!(p->flags & BR_PORT_MAB)))
>  		return -EMSGSIZE;
>
>  	timerval = br_timer_value(&p->message_age_timer);
> @@ -876,6 +878,7 @@ static const struct nla_policy
> br_port_policy[IFLA_BRPORT_MAX + 1] = {
>  	[IFLA_BRPORT_NEIGH_SUPPRESS] = { .type = NLA_U8 },
>  	[IFLA_BRPORT_ISOLATED]	= { .type = NLA_U8 },
>  	[IFLA_BRPORT_LOCKED] = { .type = NLA_U8 },
> +	[IFLA_BRPORT_MAB] = { .type = NLA_U8 },
>  	[IFLA_BRPORT_BACKUP_PORT] = { .type = NLA_U32 },
>  	[IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT] = { .type = NLA_U32 },
>  };
> @@ -943,6 +946,14 @@ static int br_setport(struct net_bridge_port *p,
> struct nlattr *tb[],
>  	br_set_port_flag(p, tb, IFLA_BRPORT_NEIGH_SUPPRESS, 
> BR_NEIGH_SUPPRESS);
>  	br_set_port_flag(p, tb, IFLA_BRPORT_ISOLATED, BR_ISOLATED);
>  	br_set_port_flag(p, tb, IFLA_BRPORT_LOCKED, BR_PORT_LOCKED);
> +	br_set_port_flag(p, tb, IFLA_BRPORT_MAB, BR_PORT_MAB);
> +
> +	if ((p->flags & BR_PORT_MAB) &&
> +	    (!(p->flags & BR_PORT_LOCKED) || !(p->flags & BR_LEARNING))) {
> +		NL_SET_ERR_MSG(extack, "MAB can only be enabled on a locked port
> with learning enabled");

It's a bit odd to get this message when turning off learning on a port 
with MAB on, e.g....

# bridge link set dev a2 learning off
Error: MAB can only be enabled on a locked port with learning enabled.