linux/net/dsa
Vladimir Oltean 5ca721c54d net: dsa: tag_ocelot: set the classified VLAN during xmit
Currently, all packets injected into Ocelot switches are classified to
VLAN 0, regardless of whether they are VLAN-tagged or not. This is
because the switch only looks at the VLAN TCI from the DSA tag.

VLAN 0 is then stripped on egress due to REW_TAG_CFG_TAG_CFG. There are
2 cases really, below is the explanation for ocelot_port_set_native_vlan:

- Port is VLAN-aware, we set REW_TAG_CFG_TAG_CFG to 1 (egress-tag all
  frames except VID 0 and the native VLAN) if a native VLAN exists, or
  to 3 otherwise (tag all frames, including VID 0).

- Port is VLAN-unaware, we set REW_TAG_CFG_TAG_CFG to 0 (port tagging
  disabled, classified VLAN never appears in the packet).

One can already see an inconsistency: when a native VLAN exists, VID 0
is egress-untagged, but when it doesn't, VID 0 is egress-tagged.

So when we do this:
ip link add br0 type bridge vlan_filtering 1
ip link set swp0 master br0
bridge vlan del dev swp0 vid 1
bridge vlan add dev swp0 vid 1 pvid # but not untagged

and we ping through swp0, packets will look like this:

MAC > 33:33:00:00:00:02, ethertype 802.1Q (0x8100): vlan 0, p 0,
	ethertype 802.1Q (0x8100), vlan 1, p 0, ethertype IPv6 (0x86dd),
	ICMP6, router solicitation, length 16

So VID 1 frames (sent that way by the Linux bridge) are encapsulated in
a VID 0 header - the classified VLAN of the packets as far as the hw is
concerned. To avoid that, what we really need to do is stop injecting
packets using the classified VLAN of 0.

This patch strips the VLAN header from the skb payload, if that VLAN
exists and if the port is under a VLAN-aware bridge. Then it copies that
VLAN header into the DSA injection frame header.

A positive side effect is that VCAP ES0 VLAN rewriting rules now work
for packets injected from the CPU into a port that's under a VLAN-aware
bridge, and we are able to match those packets by the VLAN ID that was
sent by the network stack, and not by VLAN ID 0.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-02 14:15:57 +01:00
..
dsa2.c net: dsa: Move devlink registration to be last devlink command 2021-09-27 16:32:00 +01:00
dsa_priv.h net: dsa: flush switchdev workqueue before tearing down CPU/DSA ports 2021-09-15 15:09:46 -07:00
dsa.c net: dsa: flush switchdev workqueue before tearing down CPU/DSA ports 2021-09-15 15:09:46 -07:00
Kconfig net: dsa: sja1105: break dependency between dsa_port_is_sja1105 and switch driver 2021-09-23 12:45:07 +01:00
Makefile net: dsa: build tag_8021q.c as part of DSA core 2021-07-20 06:36:42 -07:00
master.c dev_ioctl: split out ndo_eth_ioctl 2021-07-27 20:11:45 +01:00
port.c net: dsa: don't advertise 'rx-vlan-filter' when not needed 2021-08-24 09:30:58 +01:00
slave.c net: dsa: destroy the phylink instance on any error in dsa_slave_phy_setup 2021-09-15 15:03:36 -07:00
switch.c net: dsa: let drivers state that they need VLAN filtering while standalone 2021-08-24 09:30:58 +01:00
tag_8021q.c net/dsa/tag_8021q.c: remove superfluous headers 2021-09-29 11:38:21 +01:00
tag_ar9331.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_brcm.c net: dsa: create a helper for locating EtherType DSA headers on RX 2021-08-11 14:44:58 +01:00
tag_dsa.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_gswip.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_hellcreek.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_ksz.c net/dsa/tag_ksz.c: remove superfluous headers 2021-09-29 11:38:21 +01:00
tag_lan9303.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_mtk.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_ocelot_8021q.c net: update NXP copyright text 2021-09-17 13:52:17 +01:00
tag_ocelot.c net: dsa: tag_ocelot: set the classified VLAN during xmit 2021-10-02 14:15:57 +01:00
tag_qca.c net: dsa: create a helper for locating EtherType DSA headers on TX 2021-08-11 14:44:58 +01:00
tag_rtl4_a.c net: dsa: tag_rtl4_a: Drop bit 9 from egress frames 2021-09-14 19:34:03 -07:00
tag_sja1105.c net: dsa: move sja1110_process_meta_tstamp inside the tagging protocol driver 2021-09-23 12:45:07 +01:00
tag_trailer.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00
tag_xrs700x.c net: dsa: remove the struct packet_type argument from dsa_device_ops::rcv() 2021-08-02 15:13:15 +01:00