src: add support for base hook dumping

Example output:
$ nft list hook ip input
family ip hook input {
        +0000000000 nft_do_chain_inet [nf_tables]       # nft table ip filter chain input
        +0000000010 nft_do_chain_inet [nf_tables]       # nft table ip firewalld chain filter_INPUT
        +0000000100 nf_nat_ipv4_local_in [nf_nat]
        +2147483647 ipv4_confirm [nf_conntrack]
}

$ nft list hooks netdev type ingress device lo
family netdev hook ingress device lo {
        +0000000000 nft_do_chain_netdev [nf_tables]
}

$ nft list hooks inet
family ip hook prerouting {
        -0000000400 ipv4_conntrack_defrag [nf_defrag_ipv4]
        -0000000300 iptable_raw_hook [iptable_raw]
        -0000000290 nft_do_chain_inet [nf_tables]       # nft table ip firewalld chain raw_PREROUTING
        -0000000200 ipv4_conntrack_in [nf_conntrack]
        -0000000140 nft_do_chain_inet [nf_tables]       # nft table ip firewalld chain mangle_PREROUTING
        -0000000100 nf_nat_ipv4_pre_routing [nf_nat]
}
...

'nft list hooks' will display everyting except the netdev family
via successive dump request for all family:hook combinations.

Signed-off-by: Florian Westphal <fw@strlen.de>

1 files changed, 13 insertions, 0 deletions

diff --git a/src/rule.c b/src/rule.c
index 8e426c5f..dbbe744e 100644
--- a/src/rule.c
+++ b/src/rule.c
@@ -2371,6 +2371,17 @@ static int do_list_set(struct netlink_ctx *ctx, struct cmd *cmd,
 	return 0;
 }
 
+static int do_list_hooks(struct netlink_ctx *ctx, struct cmd *cmd)
+{
+	const char *devname = cmd->handle.obj.name;
+	int hooknum = -1;
+
+	if (cmd->handle.chain.name)
+		hooknum = cmd->handle.chain_id;
+
+	return mnl_nft_dump_nf_hooks(ctx, cmd->handle.family, hooknum, devname);
+}
+
 static int do_command_list(struct netlink_ctx *ctx, struct cmd *cmd)
 {
 	struct table *table = NULL;
@@ -2431,6 +2442,8 @@ static int do_command_list(struct netlink_ctx *ctx, struct cmd *cmd)
 		return do_list_flowtable(ctx, cmd, table);
 	case CMD_OBJ_FLOWTABLES:
 		return do_list_flowtables(ctx, cmd);
+	case CMD_OBJ_HOOKS:
+		return do_list_hooks(ctx, cmd);
 	default:
 		BUG("invalid command object type %u\n", cmd->obj);
 	}