path: root/iptables/nft-bridge.c
diff options
authorPhil Sutter <>2019-02-07 22:08:55 +0100
committerFlorian Westphal <>2019-02-08 17:15:06 +0100
commitaff1162b3e4b7ef805425a40306044c7d7dddc67 (patch)
tree51968e578d73a439ade1ecee760d1c800ca9bfae /iptables/nft-bridge.c
parentb06cc4e0f67f4beba7560fc329d20f108c87b5fb (diff)
ebtables-nft: Support user-defined chain policies
Legacy ebtables supports policies for user-defined chains - and what's worse, they default to ACCEPT unlike anywhere else. So lack of support for this braindead feature in ebtables-nft is actually a change of behaviour which very likely affects all ebtables users out there. The solution implemented here uses an implicit (and transparent) last rule in all user-defined ebtables-nft chains with policy other than RETURN. This rule is identified by an nft comment "XTABLES_EB_INTERNAL_POLICY_RULE" (since commit ccf154d7420c0 ("xtables: Don't use native nftables comments") nft comments are not used otherwise). To minimize interference with existing code, this policy rule is removed from chains during cache population and the policy is saved in NFTNL_CHAIN_POLICY attribute. When committing changes to the kernel, nft_commit() traverses through the list of chains and (re-)creates policy rules if required. In ebtables-nft-restore, table flushes are problematic. To avoid weird kernel error responses, introduce a custom 'table_flush' callback which removes any pending policy rule add/remove jobs prior to creating the NFT_COMPAT_TABLE_FLUSH one. I've hidden all this mess behind checks for h->family, so hopefully impact on {ip,ip6,arp}tables-nft should be negligible. Signed-off-by: Phil Sutter <> Acked-by: Pablo Neira Ayuso <> Signed-off-by: Florian Westphal <>
Diffstat (limited to 'iptables/nft-bridge.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/iptables/nft-bridge.c b/iptables/nft-bridge.c
index 848ca793..ddfbee16 100644
--- a/iptables/nft-bridge.c
+++ b/iptables/nft-bridge.c
@@ -358,7 +358,7 @@ static void nft_bridge_print_header(unsigned int format, const char *chain,
bool basechain, uint32_t refs, uint32_t entries)
printf("Bridge chain: %s, entries: %u, policy: %s\n",
- chain, entries, basechain ? pol : "RETURN");
+ chain, entries, pol ?: "RETURN");
static void print_matches_and_watchers(const struct iptables_command_state *cs,