RE: [RFC PATCH net-next v4 2/4] net/sched: flower: Add PPPoE filter

Drewek, Wojciech
2022-07-11T11:13:42Z

> -----Original Message-----
> From: Guillaume Nault <gnault@redhat.com>
> Sent: piątek, 8 lipca 2022 21:23
> To: Marcin Szycik <marcin.szycik@linux.intel.com>
> Cc: netdev@vger.kernel.org; Nguyen, Anthony L <anthony.l.nguyen@intel.com>; davem@davemloft.net;
> xiyou.wangcong@gmail.com; Brandeburg, Jesse <jesse.brandeburg@intel.com>; gustavoars@kernel.org;
> baowen.zheng@corigine.com; boris.sukholitko@broadcom.com; edumazet@google.com; kuba@kernel.org; jhs@mojatatu.com;
> jiri@resnulli.us; kurt@linutronix.de; pablo@netfilter.org; pabeni@redhat.com; paulb@nvidia.com; simon.horman@corigine.com;
> komachi.yoshiki@gmail.com; zhangkaiheb@126.com; intel-wired-lan@lists.osuosl.org; michal.swiatkowski@linux.intel.com; Drewek,
> Wojciech <wojciech.drewek@intel.com>; Lobakin, Alexandr <alexandr.lobakin@intel.com>; mostrows@earthlink.net;
> paulus@samba.org
> Subject: Re: [RFC PATCH net-next v4 2/4] net/sched: flower: Add PPPoE filter
>
> On Fri, Jul 08, 2022 at 02:24:19PM +0200, Marcin Szycik wrote:
> > From: Wojciech Drewek <wojciech.drewek@intel.com>
> >
> > Add support for PPPoE specific fields for tc-flower.
> > Those fields can be provided only when protocol was set
> > to ETH_P_PPP_SES. Defines, dump, load and set are being done here.
> >
> > Overwrite basic.n_proto only in case of PPP_IP and PPP_IPV6,
>
> ... and PPP_MPLS_UC/PPP_MPLS_MC in this new patch version.
>
> > otherwise leave it as ETH_P_PPP_SES.
> >
> > Signed-off-by: Wojciech Drewek <wojciech.drewek@intel.com>
> > ---
> > v4:
> > * support of MPLS inner fields
> > * session_id stored in __be16
> >
> > include/uapi/linux/pkt_cls.h | 3 ++
> > net/sched/cls_flower.c | 61 ++++++++++++++++++++++++++++++++++++
> > 2 files changed, 64 insertions(+)
> >
> > diff --git a/include/uapi/linux/pkt_cls.h b/include/uapi/linux/pkt_cls.h
> > index 9a2ee1e39fad..c142c0f8ed8a 100644
> > --- a/include/uapi/linux/pkt_cls.h
> > +++ b/include/uapi/linux/pkt_cls.h
> > @@ -589,6 +589,9 @@ enum {
> >
> > TCA_FLOWER_KEY_NUM_OF_VLANS, /* u8 */
> >
> > + TCA_FLOWER_KEY_PPPOE_SID, /* be16 */
> > + TCA_FLOWER_KEY_PPP_PROTO, /* be16 */
> > +
> > __TCA_FLOWER_MAX,
> > };
> >
> > diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
> > index dcca70144dff..2a0ebad0e61c 100644
> > --- a/net/sched/cls_flower.c
> > +++ b/net/sched/cls_flower.c
> > @@ -16,6 +16,7 @@
> > #include <linux/in6.h>
> > #include <linux/ip.h>
> > #include <linux/mpls.h>
> > +#include <linux/ppp_defs.h>
> >
> > #include <net/sch_generic.h>
> > #include <net/pkt_cls.h>
> > @@ -73,6 +74,7 @@ struct fl_flow_key {
> > struct flow_dissector_key_ct ct;
> > struct flow_dissector_key_hash hash;
> > struct flow_dissector_key_num_of_vlans num_of_vlans;
> > + struct flow_dissector_key_pppoe pppoe;
> > } __aligned(BITS_PER_LONG / 8); /* Ensure that we can do comparisons as longs. */
> >
> > struct fl_flow_mask_range {
> > @@ -714,6 +716,8 @@ static const struct nla_policy fl_policy[TCA_FLOWER_MAX + 1] = {
> > [TCA_FLOWER_KEY_HASH] = { .type = NLA_U32 },
> > [TCA_FLOWER_KEY_HASH_MASK] = { .type = NLA_U32 },
> > [TCA_FLOWER_KEY_NUM_OF_VLANS] = { .type = NLA_U8 },
> > + [TCA_FLOWER_KEY_PPPOE_SID] = { .type = NLA_U16 },
> > + [TCA_FLOWER_KEY_PPP_PROTO] = { .type = NLA_U16 },
> >
> > };
> >
> > @@ -1041,6 +1045,50 @@ static void fl_set_key_vlan(struct nlattr **tb,
> > }
> > }
> >
> > +static void fl_set_key_pppoe(struct nlattr **tb,
> > + struct flow_dissector_key_pppoe *key_val,
> > + struct flow_dissector_key_pppoe *key_mask,
> > + struct fl_flow_key *key,
> > + struct fl_flow_key *mask)
> > +{
> > + /* key_val::type must be set to ETH_P_PPP_SES
> > + * because ETH_P_PPP_SES was stored in basic.n_proto
> > + * which might get overwritten by ppp_proto
> > + * or might be set to 0, the role of key_val::type
> > + * is simmilar to vlan_key::tpid
>
> Didn't you mean "vlan_tpid"?

Yes, is vlan_key::tpid not clear/valid?

>
> > + */
> > + key_val->type = htons(ETH_P_PPP_SES);
> > + key_mask->type = cpu_to_be16(~0);
> > +
> > + if (tb[TCA_FLOWER_KEY_PPPOE_SID]) {
> > + key_val->session_id =
> > + nla_get_be16(tb[TCA_FLOWER_KEY_PPPOE_SID]);
> > + key_mask->session_id = cpu_to_be16(~0);
> > + }
> > + if (tb[TCA_FLOWER_KEY_PPP_PROTO]) {
> > + key_val->ppp_proto =
> > + nla_get_be16(tb[TCA_FLOWER_KEY_PPP_PROTO]);
> > + key_mask->ppp_proto = cpu_to_be16(~0);
> > +
> > + if (key_val->ppp_proto == htons(PPP_IP)) {
> > + key->basic.n_proto = htons(ETH_P_IP);
> > + mask->basic.n_proto = cpu_to_be16(~0);
> > + } else if (key_val->ppp_proto == htons(PPP_IPV6)) {
> > + key->basic.n_proto = htons(ETH_P_IPV6);
> > + mask->basic.n_proto = cpu_to_be16(~0);
> > + } else if (key_val->ppp_proto == htons(PPP_MPLS_UC)) {
> > + key->basic.n_proto = htons(ETH_P_MPLS_UC);
> > + mask->basic.n_proto = cpu_to_be16(~0);
> > + } else if (key_val->ppp_proto == htons(PPP_MPLS_MC)) {
> > + key->basic.n_proto = htons(ETH_P_MPLS_MC);
> > + mask->basic.n_proto = cpu_to_be16(~0);
> > + }
> > + } else {
> > + key->basic.n_proto = 0;
> > + mask->basic.n_proto = cpu_to_be16(0);
> > + }
> > +}
> > +
> > static void fl_set_key_flag(u32 flower_key, u32 flower_mask,
> > u32 *dissector_key, u32 *dissector_mask,
> > u32 flower_flag_bit, u32 dissector_flag_bit)
> > @@ -1651,6 +1699,9 @@ static int fl_set_key(struct net *net, struct nlattr **tb,
> > }
> > }
> >
> > + if (key->basic.n_proto == htons(ETH_P_PPP_SES))
> > + fl_set_key_pppoe(tb, &key->pppoe, &mask->pppoe, key, mask);
> > +
> > if (key->basic.n_proto == htons(ETH_P_IP) ||
> > key->basic.n_proto == htons(ETH_P_IPV6)) {
> > fl_set_key_val(tb, &key->basic.ip_proto, TCA_FLOWER_KEY_IP_PROTO,
> > @@ -1923,6 +1974,8 @@ static void fl_init_dissector(struct flow_dissector *dissector,
> > FLOW_DISSECTOR_KEY_HASH, hash);
> > FL_KEY_SET_IF_MASKED(mask, keys, cnt,
> > FLOW_DISSECTOR_KEY_NUM_OF_VLANS, num_of_vlans);
> > + FL_KEY_SET_IF_MASKED(mask, keys, cnt,
> > + FLOW_DISSECTOR_KEY_PPPOE, pppoe);
> >
> > skb_flow_dissector_init(dissector, keys, cnt);
> > }
> > @@ -3051,6 +3104,14 @@ static int fl_dump_key(struct sk_buff *skb, struct net *net,
> > fl_dump_key_ip(skb, false, &key->ip, &mask->ip)))
> > goto nla_put_failure;
> >
> > + if (mask->pppoe.session_id &&
> > + nla_put_be16(skb, TCA_FLOWER_KEY_PPPOE_SID, key->pppoe.session_id))
> > + goto nla_put_failure;
> > +
> > + if (mask->basic.n_proto && mask->pppoe.ppp_proto &&
> > + nla_put_be16(skb, TCA_FLOWER_KEY_PPP_PROTO, key->pppoe.ppp_proto))
> > + goto nla_put_failure;
> > +
> > if (key->control.addr_type == FLOW_DISSECTOR_KEY_IPV4_ADDRS &&
> > (fl_dump_key_val(skb, &key->ipv4.src, TCA_FLOWER_KEY_IPV4_SRC,
> > &mask->ipv4.src, TCA_FLOWER_KEY_IPV4_SRC_MASK,
> > --
> > 2.35.1
> >