Revert "netfilter: nf_tables: Add notifications for hook changes"

This reverts commit 465b9ee0ee7bc268d7f261356afd6c4262e48d82.

Such notifications fit better into core or nfnetlink_hook code,
following the NFNL_MSG_HOOK_GET message format.

Signed-off-by: Phil Sutter <[e-mail]>
Signed-off-by: Pablo Neira Ayuso <[e-mail]>

include/net/netfilter/nf_tables.h

···
 int nf_tables_bind_chain(const struct nft_ctx *ctx, struct nft_chain *chain);
 void nf_tables_unbind_chain(const struct nft_ctx *ctx, struct nft_chain *chain);
 
-struct nft_hook;
-void nf_tables_chain_device_notify(const struct nft_chain *chain,
-				   const struct nft_hook *hook,
-				   const struct net_device *dev, int event);
-
 enum nft_chain_types {
 	NFT_CHAIN_T_DEFAULT = 0,
 	NFT_CHAIN_T_ROUTE,

include/uapi/linux/netfilter/nf_tables.h

···
 	NFT_MSG_DESTROYOBJ,
 	NFT_MSG_DESTROYFLOWTABLE,
 	NFT_MSG_GETSETELEM_RESET,
-	NFT_MSG_NEWDEV,
-	NFT_MSG_DELDEV,
 	NFT_MSG_MAX,
 };
 
···
  * enum nft_device_attributes - nf_tables device netlink attributes
  *
  * @NFTA_DEVICE_NAME: name of this device (NLA_STRING)
- * @NFTA_DEVICE_TABLE: table containing the flowtable or chain hooking into the device (NLA_STRING)
- * @NFTA_DEVICE_FLOWTABLE: flowtable hooking into the device (NLA_STRING)
- * @NFTA_DEVICE_CHAIN: chain hooking into the device (NLA_STRING)
- * @NFTA_DEVICE_SPEC: hook spec matching the device (NLA_STRING)
  */
 enum nft_devices_attributes {
 	NFTA_DEVICE_UNSPEC,
 	NFTA_DEVICE_NAME,
-	NFTA_DEVICE_TABLE,
-	NFTA_DEVICE_FLOWTABLE,
-	NFTA_DEVICE_CHAIN,
-	NFTA_DEVICE_SPEC,
 	__NFTA_DEVICE_MAX
 };
 #define NFTA_DEVICE_MAX		(__NFTA_DEVICE_MAX - 1)

include/uapi/linux/netfilter/nfnetlink.h

···
 #define NFNLGRP_ACCT_QUOTA		NFNLGRP_ACCT_QUOTA
 	NFNLGRP_NFTRACE,
 #define NFNLGRP_NFTRACE			NFNLGRP_NFTRACE
-	NFNLGRP_NFT_DEV,
-#define NFNLGRP_NFT_DEV			NFNLGRP_NFT_DEV
 	__NFNLGRP_MAX,
 };
 #define NFNLGRP_MAX	(__NFNLGRP_MAX - 1)

net/netfilter/nf_tables_api.c

···
 }
 EXPORT_SYMBOL_GPL(nft_hook_find_ops_rcu);
 
-static void
-nf_tables_device_notify(const struct nft_table *table, int attr,
-			const char *name, const struct nft_hook *hook,
-			const struct net_device *dev, int event)
-{
-	struct net *net = dev_net(dev);
-	struct nlmsghdr *nlh;
-	struct sk_buff *skb;
-	u16 flags = 0;
-
-	if (!nfnetlink_has_listeners(net, NFNLGRP_NFT_DEV))
-		return;
-
-	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
-	if (!skb)
-		goto err;
-
-	event = event == NETDEV_REGISTER ? NFT_MSG_NEWDEV : NFT_MSG_DELDEV;
-	event = nfnl_msg_type(NFNL_SUBSYS_NFTABLES, event);
-	nlh = nfnl_msg_put(skb, 0, 0, event, flags, table->family,
-			   NFNETLINK_V0, nft_base_seq(net));
-	if (!nlh)
-		goto err;
-
-	if (nla_put_string(skb, NFTA_DEVICE_TABLE, table->name) ||
-	    nla_put_string(skb, attr, name) ||
-	    nla_put(skb, NFTA_DEVICE_SPEC, hook->ifnamelen, hook->ifname) ||
-	    nla_put_string(skb, NFTA_DEVICE_NAME, dev->name))
-		goto err;
-
-	nlmsg_end(skb, nlh);
-	nfnetlink_send(skb, net, 0, NFNLGRP_NFT_DEV,
-		       nlmsg_report(nlh), GFP_KERNEL);
-	return;
-err:
-	if (skb)
-		kfree_skb(skb);
-	nfnetlink_set_err(net, 0, NFNLGRP_NFT_DEV, -ENOBUFS);
-}
-
-void
-nf_tables_chain_device_notify(const struct nft_chain *chain,
-			      const struct nft_hook *hook,
-			      const struct net_device *dev, int event)
-{
-	nf_tables_device_notify(chain->table, NFTA_DEVICE_CHAIN,
-				chain->name, hook, dev, event);
-}
-
-static void
-nf_tables_flowtable_device_notify(const struct nft_flowtable *ft,
-				  const struct nft_hook *hook,
-				  const struct net_device *dev, int event)
-{
-	nf_tables_device_notify(ft->table, NFTA_DEVICE_FLOWTABLE,
-				ft->name, hook, dev, event);
-}
-
 static int nft_flowtable_event(unsigned long event, struct net_device *dev,
 			       struct nft_flowtable *flowtable, bool changename)
 {
···
 			list_add_tail_rcu(&ops->list, &hook->ops_list);
 			break;
 		}
-		nf_tables_flowtable_device_notify(flowtable, hook, dev, event);
 		break;
 	}
 	return 0;

net/netfilter/nfnetlink.c

···
 	[NFNLGRP_NFTABLES]		= NFNL_SUBSYS_NFTABLES,
 	[NFNLGRP_ACCT_QUOTA]		= NFNL_SUBSYS_ACCT,
 	[NFNLGRP_NFTRACE]		= NFNL_SUBSYS_NFTABLES,
-	[NFNLGRP_NFT_DEV]		= NFNL_SUBSYS_NFTABLES,
 };
 
 static struct nfnl_net *nfnl_pernet(struct net *net)

net/netfilter/nft_chain_filter.c

···
 			list_add_tail_rcu(&ops->list, &hook->ops_list);
 			break;
 		}
-		nf_tables_chain_device_notify(&basechain->chain,
-					      hook, dev, event);
 		break;
 	}
 	return 0;