From: Pablo Neira Ayuso pablo@netfilter.org
[ Upstream commit 783003f3bb8a565326e89d18bbd948ad8ffc816a ]
The nftables offload parser sets FLOW_DISSECTOR_KEY_BASIC .n_proto to the ethertype field in the ethertype frame. However:
- FLOW_DISSECTOR_KEY_BASIC .n_proto field always stores either IPv4 or IPv6 ethertypes. - FLOW_DISSECTOR_KEY_VLAN .vlan_tpid stores either the 802.1q and 802.1ad ethertypes. Same as for FLOW_DISSECTOR_KEY_CVLAN.
This function adjusts the flow dissector to handle two scenarios:
1) FLOW_DISSECTOR_KEY_VLAN .vlan_tpid is set to 802.1q or 802.1ad. Then, transfer: - the .n_proto field to FLOW_DISSECTOR_KEY_VLAN .tpid. - the original FLOW_DISSECTOR_KEY_VLAN .tpid to the FLOW_DISSECTOR_KEY_CVLAN .tpid - the original FLOW_DISSECTOR_KEY_CVLAN .tpid to the .n_proto field.
2) .n_proto is set to 802.1q or 802.1ad. Then, transfer: - the .n_proto field to FLOW_DISSECTOR_KEY_VLAN .tpid. - the original FLOW_DISSECTOR_KEY_VLAN .tpid to the .n_proto field.
Fixes: a82055af5959 ("netfilter: nft_payload: add VLAN offload support") Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/netfilter/nf_tables_offload.c | 44 +++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+)
diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c index 9ae14270c543..2b00f7f47693 100644 --- a/net/netfilter/nf_tables_offload.c +++ b/net/netfilter/nf_tables_offload.c @@ -45,6 +45,48 @@ void nft_flow_rule_set_addr_type(struct nft_flow_rule *flow, offsetof(struct nft_flow_key, control); }
+struct nft_offload_ethertype { + __be16 value; + __be16 mask; +}; + +static void nft_flow_rule_transfer_vlan(struct nft_offload_ctx *ctx, + struct nft_flow_rule *flow) +{ + struct nft_flow_match *match = &flow->match; + struct nft_offload_ethertype ethertype; + + if (match->dissector.used_keys & BIT(FLOW_DISSECTOR_KEY_CONTROL) && + match->key.basic.n_proto != htons(ETH_P_8021Q) && + match->key.basic.n_proto != htons(ETH_P_8021AD)) + return; + + ethertype.value = match->key.basic.n_proto; + ethertype.mask = match->mask.basic.n_proto; + + if (match->dissector.used_keys & BIT(FLOW_DISSECTOR_KEY_VLAN) && + (match->key.vlan.vlan_tpid == htons(ETH_P_8021Q) || + match->key.vlan.vlan_tpid == htons(ETH_P_8021AD))) { + match->key.basic.n_proto = match->key.cvlan.vlan_tpid; + match->mask.basic.n_proto = match->mask.cvlan.vlan_tpid; + match->key.cvlan.vlan_tpid = match->key.vlan.vlan_tpid; + match->mask.cvlan.vlan_tpid = match->mask.vlan.vlan_tpid; + match->key.vlan.vlan_tpid = ethertype.value; + match->mask.vlan.vlan_tpid = ethertype.mask; + match->dissector.offset[FLOW_DISSECTOR_KEY_CVLAN] = + offsetof(struct nft_flow_key, cvlan); + match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_CVLAN); + } else { + match->key.basic.n_proto = match->key.vlan.vlan_tpid; + match->mask.basic.n_proto = match->mask.vlan.vlan_tpid; + match->key.vlan.vlan_tpid = ethertype.value; + match->mask.vlan.vlan_tpid = ethertype.mask; + match->dissector.offset[FLOW_DISSECTOR_KEY_VLAN] = + offsetof(struct nft_flow_key, vlan); + match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_VLAN); + } +} + struct nft_flow_rule *nft_flow_rule_create(struct net *net, const struct nft_rule *rule) { @@ -89,6 +131,8 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *net,
expr = nft_expr_next(expr); } + nft_flow_rule_transfer_vlan(ctx, flow); + flow->proto = ctx->dep.l3num; kfree(ctx);