[PATCH net-next v4 3/3] netfilter: nf_tables_offload: support indr block call

[wenxu@ucloud.cn]

From: wenxu <wenxu@ucloud.cn>

nftable support indr-block call. It makes nftable an offload vlan
and tunnel device.

nft add table netdev firewall
nft add chain netdev firewall aclout { type filter hook ingress offload device mlx_pf0vf0 priority - 300 \; }
nft add rule netdev firewall aclout ip daddr 10.0.0.1 fwd to vlan0
nft add chain netdev firewall aclin { type filter hook ingress device vlan0 priority - 300 \; }
nft add rule netdev firewall aclin ip daddr 10.0.0.7 fwd to mlx_pf0vf0

Signed-off-by: wenxu <wenxu@ucloud.cn>
---
v3: subsys_initcall for init_flow_indr_rhashtable
v4: guarantee only one offload base chain used per indr dev. 
If the indr_block_cmd bind fail return unsupported.

 net/netfilter/nf_tables_offload.c | 131 +++++++++++++++++++++++++++++++-------
 1 file changed, 107 insertions(+), 24 deletions(-)

diff --git a/net/netfilter/nf_tables_offload.c b/net/netfilter/nf_tables_offload.c
index 64f5fd5..19214ad 100644
--- a/net/netfilter/nf_tables_offload.c
+++ b/net/netfilter/nf_tables_offload.c
@@ -171,24 +171,123 @@ static int nft_flow_offload_unbind(struct flow_block_offload *bo,
 	return 0;
 }
 
+static int nft_block_setup(struct nft_base_chain *basechain,
+			   struct flow_block_offload *bo,
+			   enum flow_block_command cmd)
+{
+	int err;
+
+	switch (cmd) {
+	case FLOW_BLOCK_BIND:
+		err = nft_flow_offload_bind(bo, basechain);
+		break;
+	case FLOW_BLOCK_UNBIND:
+		err = nft_flow_offload_unbind(bo, basechain);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		err = -EOPNOTSUPP;
+	}
+
+	return err;
+}
+
+static int nft_block_offload_cmd(struct nft_base_chain *chain,
+				 struct net_device *dev,
+				 enum flow_block_command cmd)
+{
+	struct netlink_ext_ack extack = {};
+	struct flow_block_offload bo = {};
+	int err;
+
+	bo.net = dev_net(dev);
+	bo.block = &chain->flow_block;
+	bo.command = cmd;
+	bo.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
+	bo.extack = &extack;
+	INIT_LIST_HEAD(&bo.cb_list);
+
+	err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
+	if (err < 0)
+		return err;
+
+	return nft_block_setup(chain, &bo, cmd);
+}
+
+static void nft_indr_block_ing_cmd(struct net_device *dev,
+				   struct flow_block *flow_block,
+				   struct flow_indr_block_cb *indr_block_cb,
+				   enum flow_block_command cmd)
+{
+	struct netlink_ext_ack extack = {};
+	struct flow_block_offload bo = {};
+	struct nft_base_chain *chain;
+
+	if (flow_block)
+		return;
+
+	chain = container_of(flow_block, struct nft_base_chain, flow_block);
+
+	bo.net = dev_net(dev);
+	bo.block = flow_block;
+	bo.command = cmd;
+	bo.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
+	bo.extack = &extack;
+	INIT_LIST_HEAD(&bo.cb_list);
+
+	indr_block_cb->cb(dev, indr_block_cb->cb_priv, TC_SETUP_BLOCK, &bo);
+
+	nft_block_setup(chain, &bo, cmd);
+}
+
+static int nft_indr_block_offload_cmd(struct nft_base_chain *chain,
+				      struct net_device *dev,
+				      enum flow_block_command cmd)
+{
+	struct flow_indr_block_cb *indr_block_cb;
+	struct flow_indr_block_dev *indr_dev;
+	struct flow_block_offload bo = {};
+	struct netlink_ext_ack extack = {};
+
+	bo.net = dev_net(dev);
+	bo.block = &chain->flow_block;
+	bo.command = cmd;
+	bo.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
+	bo.extack = &extack;
+	INIT_LIST_HEAD(&bo.cb_list);
+
+	indr_dev = flow_indr_block_dev_lookup(dev);
+	if (!indr_dev)
+		return -EOPNOTSUPP;
+
+	indr_dev->flow_block = cmd == FLOW_BLOCK_BIND ? &chain->flow_block : NULL;
+	indr_dev->ing_cmd_cb = cmd == FLOW_BLOCK_BIND ? nft_indr_block_ing_cmd : NULL;
+
+	list_for_each_entry(indr_block_cb, &indr_dev->cb_list, list)
+		indr_block_cb->cb(dev, indr_block_cb->cb_priv, TC_SETUP_BLOCK,
+				  &bo);
+
+	if (list_empty(&bo.cb_list))
+		return -EOPNOTSUPP;
+
+	return nft_block_setup(chain, &bo, cmd);
+}
+
 #define FLOW_SETUP_BLOCK TC_SETUP_BLOCK
 
 static int nft_flow_offload_chain(struct nft_trans *trans,
 				  enum flow_block_command cmd)
 {
 	struct nft_chain *chain = trans->ctx.chain;
-	struct netlink_ext_ack extack = {};
-	struct flow_block_offload bo = {};
 	struct nft_base_chain *basechain;
 	struct net_device *dev;
-	int err;
 
 	if (!nft_is_base_chain(chain))
 		return -EOPNOTSUPP;
 
 	basechain = nft_base_chain(chain);
 	dev = basechain->ops.dev;
-	if (!dev || !dev->netdev_ops->ndo_setup_tc)
+	if (!dev)
 		return -EOPNOTSUPP;
 
 	/* Only default policy to accept is supported for now. */
@@ -197,26 +296,10 @@ static int nft_flow_offload_chain(struct nft_trans *trans,
 	    nft_trans_chain_policy(trans) != NF_ACCEPT)
 		return -EOPNOTSUPP;
 
-	bo.command = cmd;
-	bo.block = &basechain->flow_block;
-	bo.binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
-	bo.extack = &extack;
-	INIT_LIST_HEAD(&bo.cb_list);
-
-	err = dev->netdev_ops->ndo_setup_tc(dev, FLOW_SETUP_BLOCK, &bo);
-	if (err < 0)
-		return err;
-
-	switch (cmd) {
-	case FLOW_BLOCK_BIND:
-		err = nft_flow_offload_bind(&bo, basechain);
-		break;
-	case FLOW_BLOCK_UNBIND:
-		err = nft_flow_offload_unbind(&bo, basechain);
-		break;
-	}
-
-	return err;
+	if (dev->netdev_ops->ndo_setup_tc)
+		return nft_block_offload_cmd(basechain, dev, cmd);
+	else
+		return nft_indr_block_offload_cmd(basechain, dev, cmd);
 }
 
 int nft_flow_rule_offload_commit(struct net *net)
-- 
1.8.3.1