Below configuration, mangle,filter and security tables have no rule:
# iptables -t raw -I PREROUTING 1 -p tcp --dport 22 -j TRACE
# sysctl net.netfilter.nf_log.2=nf_log_ipv4
There are 5 logs for incoming ssh packet:
kernel: [ 7018.727278] TRACE: raw:PREROUTING:policy:2 IN=enp9s0 ...
kernel: [ 7018.727304] TRACE: mangle:PREROUTING:policy:1 IN=enp9s0 ...
kernel: [ 7018.727327] TRACE: mangle:INPUT:policy:1 IN=enp9s0 ...
kernel: [ 7018.727343] TRACE: filter:INPUT:policy:1 IN=enp9s0 ...
kernel: [ 7018.727359] TRACE: security:INPUT:policy:1 IN=enp9s0 ...
Signed-off-by: kai zhang <zhangkaiheb@xxxxxxx>
---
net/ipv4/netfilter/ip_tables.c | 4 +++-
net/ipv6/netfilter/ip6_tables.c | 4 +++-
2 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 2ed7c58b4..5f0e6096e 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -304,9 +304,11 @@ ipt_do_table(void *priv,
#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
/* The packet is traced: log it */
- if (unlikely(skb->nf_trace))
+ if (unlikely(skb->nf_trace)) {
trace_packet(state->net, skb, hook, state->in,
state->out, table->name, private, e);
+ nf_reset_trace(skb);
+ }
#endif
/* Standard target? */
if (!t->u.kernel.target->target) {
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 2d816277f..ae842a835 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -327,9 +327,11 @@ ip6t_do_table(void *priv, struct sk_buff *skb,
#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE)
/* The packet is traced: log it */
- if (unlikely(skb->nf_trace))
+ if (unlikely(skb->nf_trace)) {
trace_packet(state->net, skb, hook, state->in,
state->out, table->name, private, e);
+ nf_reset_trace(skb);
+ }
#endif
/* Standard target? */
if (!t->u.kernel.target->target) {
--
2.30.2
