diff mbox series

[net-next,v4,3/5] flow_dissector: Add number of vlan tags dissector

Message ID 20220419081434.5192-4-boris.sukholitko@broadcom.com (mailing list archive)
State Accepted
Commit 34951fcf26c59e78ae430fba1fce7c08b1871249
Delegated to: Netdev Maintainers
Headers show
Series net/sched: flower: match on the number of vlan tags | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 5840 this patch: 5840
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 1151 this patch: 1151
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 5979 this patch: 5979
netdev/checkpatch warning WARNING: line length of 85 exceeds 80 columns WARNING: line length of 92 exceeds 80 columns WARNING: line length of 93 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 7 this patch: 7
netdev/source_inline success Was 0 now: 0

Commit Message

Boris Sukholitko April 19, 2022, 8:14 a.m. UTC
Our customers in the fiber telecom world have network configurations
where they would like to control their traffic according to the number
of tags appearing in the packet.

For example, TR247 GPON conformance test suite specification mostly
talks about untagged, single, double tagged packets and gives lax
guidelines on the vlan protocol vs. number of vlan tags.

This is different from the common IT networks where 802.1Q and 802.1ad
protocols are usually describe single and double tagged packet. GPON
configurations that we work with have arbitrary mix the above protocols
and number of vlan tags in the packet.

The goal is to make the following TC commands possible:

tc filter add dev eth1 ingress flower \
  num_of_vlans 1 vlan_prio 5 action drop

From our logs, we have redirect rules such that:

tc filter add dev $GPON ingress flower num_of_vlans $N \
     action mirred egress redirect dev $DEV

where N can range from 0 to 3 and $DEV is the function of $N.

Also there are rules setting skb mark based on the number of vlans:

tc filter add dev $GPON ingress flower num_of_vlans $N vlan_prio \
    $P action skbedit mark $M

This new dissector allows extracting the number of vlan tags existing in
the packet.

Signed-off-by: Boris Sukholitko <boris.sukholitko@broadcom.com>
---
 include/net/flow_dissector.h |  9 +++++++++
 net/core/flow_dissector.c    | 20 ++++++++++++++++++++
 2 files changed, 29 insertions(+)
diff mbox series

Patch

diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
index 9f65f1bfbd24..a4c6057c7097 100644
--- a/include/net/flow_dissector.h
+++ b/include/net/flow_dissector.h
@@ -253,6 +253,14 @@  struct flow_dissector_key_hash {
 	u32 hash;
 };
 
+/**
+ * struct flow_dissector_key_num_of_vlans:
+ * @num_of_vlans: num_of_vlans value
+ */
+struct flow_dissector_key_num_of_vlans {
+	u8 num_of_vlans;
+};
+
 enum flow_dissector_key_id {
 	FLOW_DISSECTOR_KEY_CONTROL, /* struct flow_dissector_key_control */
 	FLOW_DISSECTOR_KEY_BASIC, /* struct flow_dissector_key_basic */
@@ -282,6 +290,7 @@  enum flow_dissector_key_id {
 	FLOW_DISSECTOR_KEY_META, /* struct flow_dissector_key_meta */
 	FLOW_DISSECTOR_KEY_CT, /* struct flow_dissector_key_ct */
 	FLOW_DISSECTOR_KEY_HASH, /* struct flow_dissector_key_hash */
+	FLOW_DISSECTOR_KEY_NUM_OF_VLANS, /* struct flow_dissector_key_num_of_vlans */
 
 	FLOW_DISSECTOR_KEY_MAX,
 };
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 6f7ec72016dc..6aee04f75e3e 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -1035,6 +1035,16 @@  bool __skb_flow_dissect(const struct net *net,
 		memcpy(key_eth_addrs, eth, sizeof(*key_eth_addrs));
 	}
 
+	if (dissector_uses_key(flow_dissector,
+			       FLOW_DISSECTOR_KEY_NUM_OF_VLANS)) {
+		struct flow_dissector_key_num_of_vlans *key_num_of_vlans;
+
+		key_num_of_vlans = skb_flow_dissector_target(flow_dissector,
+							     FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
+							     target_container);
+		key_num_of_vlans->num_of_vlans = 0;
+	}
+
 proto_again:
 	fdret = FLOW_DISSECT_RET_CONTINUE;
 
@@ -1158,6 +1168,16 @@  bool __skb_flow_dissect(const struct net *net,
 			nhoff += sizeof(*vlan);
 		}
 
+		if (dissector_uses_key(flow_dissector,
+				       FLOW_DISSECTOR_KEY_NUM_OF_VLANS)) {
+			struct flow_dissector_key_num_of_vlans *key_nvs;
+
+			key_nvs = skb_flow_dissector_target(flow_dissector,
+							    FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
+							    target_container);
+			key_nvs->num_of_vlans++;
+		}
+
 		if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
 			dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
 		} else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {