nft: cache: Introduce nft_cache_add_chain()

This is a convenience function for adding a chain to cache, for now just
a simple wrapper around nftnl_chain_list_add_tail().

Signed-off-by: Phil Sutter <phil@nwl.cc>

3 files changed, 19 insertions, 12 deletions

diff --git a/iptables/nft-cache.c b/iptables/nft-cache.c
index 32cfd6cf..afa655d7 100644
--- a/iptables/nft-cache.c
+++ b/iptables/nft-cache.c
@@ -165,6 +165,13 @@ static int fetch_table_cache(struct nft_handle *h)
 	return 1;
 }
 
+int nft_cache_add_chain(struct nft_handle *h, const struct builtin_table *t,
+			struct nftnl_chain *c)
+{
+	nftnl_chain_list_add_tail(c, h->cache->table[t->type].chains);
+	return 0;
+}
+
 struct nftnl_chain_list_cb_data {
 	struct nft_handle *h;
 	const struct builtin_table *t;
@@ -174,7 +181,6 @@ static int nftnl_chain_list_cb(const struct nlmsghdr *nlh, void *data)
 {
 	struct nftnl_chain_list_cb_data *d = data;
 	const struct builtin_table *t = d->t;
-	struct nftnl_chain_list *list;
 	struct nft_handle *h = d->h;
 	struct nftnl_chain *c;
 	const char *tname;
@@ -196,8 +202,8 @@ static int nftnl_chain_list_cb(const struct nlmsghdr *nlh, void *data)
 		goto out;
 	}
 
-	list = h->cache->table[t->type].chains;
-	nftnl_chain_list_add_tail(c, list);
+	if (nft_cache_add_chain(h, t, c))
+		goto out;
 
 	return MNL_CB_OK;
 out:
diff --git a/iptables/nft-cache.h b/iptables/nft-cache.h
index 76f9fbb6..d97f8de2 100644
--- a/iptables/nft-cache.h
+++ b/iptables/nft-cache.h
@@ -3,6 +3,7 @@
 
 struct nft_handle;
 struct nft_cmd;
+struct builtin_table;
 
 void nft_cache_level_set(struct nft_handle *h, int level,
 			 const struct nft_cmd *cmd);
@@ -12,6 +13,8 @@ void flush_chain_cache(struct nft_handle *h, const char *tablename);
 int flush_rule_cache(struct nft_handle *h, const char *table,
 		     struct nftnl_chain *c);
 void nft_cache_build(struct nft_handle *h);
+int nft_cache_add_chain(struct nft_handle *h, const struct builtin_table *t,
+			struct nftnl_chain *c);
 
 struct nftnl_chain_list *
 nft_chain_list_get(struct nft_handle *h, const char *table, const char *chain);
diff --git a/iptables/nft.c b/iptables/nft.c
index 24e49db4..d1f6d417 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -697,7 +697,7 @@ static void nft_chain_builtin_add(struct nft_handle *h,
 		return;
 
 	batch_chain_add(h, NFT_COMPAT_CHAIN_ADD, c);
-	nftnl_chain_list_add_tail(c, h->cache->table[table->type].chains);
+	nft_cache_add_chain(h, table, c);
 }
 
 /* find if built-in table already exists */
@@ -1712,7 +1712,7 @@ err:
 
 int nft_chain_user_add(struct nft_handle *h, const char *chain, const char *table)
 {
-	struct nftnl_chain_list *list;
+	const struct builtin_table *t;
 	struct nftnl_chain *c;
 
 	nft_fn = nft_chain_user_add;
@@ -1736,9 +1736,8 @@ int nft_chain_user_add(struct nft_handle *h, const char *chain, const char *tabl
 	if (!batch_chain_add(h, NFT_COMPAT_CHAIN_USER_ADD, c))
 		return 0;
 
-	list = nft_chain_list_get(h, table, chain);
-	if (list)
-		nftnl_chain_list_add(c, list);
+	t = nft_table_builtin_find(h, table);
+	nft_cache_add_chain(h, t, c);
 
 	/* the core expects 1 for success and 0 for error */
 	return 1;
@@ -1746,7 +1745,7 @@ int nft_chain_user_add(struct nft_handle *h, const char *chain, const char *tabl
 
 int nft_chain_restore(struct nft_handle *h, const char *chain, const char *table)
 {
-	struct nftnl_chain_list *list;
+	const struct builtin_table *t;
 	struct obj_update *obj;
 	struct nftnl_chain *c;
 	bool created = false;
@@ -1763,9 +1762,8 @@ int nft_chain_restore(struct nft_handle *h, const char *chain, const char *table
 		nftnl_chain_set_str(c, NFTNL_CHAIN_NAME, chain);
 		created = true;
 
-		list = nft_chain_list_get(h, table, chain);
-		if (list)
-			nftnl_chain_list_add(c, list);
+		t = nft_table_builtin_find(h, table);
+		nft_cache_add_chain(h, t, c);
 	} else {
 		/* If the chain should vanish meanwhile, kernel genid changes
 		 * and the transaction is refreshed enabling the chain add