This adds translation capabilities when encountering SYNPROXY inside
iptables rules.
Signed-off-by: Jose M. Guisado Gomez <guigom@xxxxxxxxxx>
---
extensions/libxt_SYNPROXY.c | 23 +++++++++++++++++++++++
extensions/libxt_SYNPROXY.txlate | 2 ++
2 files changed, 25 insertions(+)
create mode 100644 extensions/libxt_SYNPROXY.txlate
diff --git a/extensions/libxt_SYNPROXY.c b/extensions/libxt_SYNPROXY.c
index 475590ea..6a0b913e 100644
--- a/extensions/libxt_SYNPROXY.c
+++ b/extensions/libxt_SYNPROXY.c
@@ -106,6 +106,28 @@ static void SYNPROXY_save(const void *ip, const struct xt_entry_target *target)
printf(" --ecn");
}
+static int SYNPROXY_xlate(struct xt_xlate *xl,
+ const struct xt_xlate_tg_params *params)
+{
+ const struct xt_synproxy_info *info =
+ (const struct xt_synproxy_info *)params->target->data;
+
+ xt_xlate_add(xl, "synproxy ");
+
+ if (info->options & XT_SYNPROXY_OPT_SACK_PERM)
+ xt_xlate_add(xl, "sack-perm ");
+ if (info->options & XT_SYNPROXY_OPT_TIMESTAMP)
+ xt_xlate_add(xl, "timestamp ");
+ if (info->options & XT_SYNPROXY_OPT_WSCALE)
+ xt_xlate_add(xl, "wscale %u ", info->wscale);
+ if (info->options & XT_SYNPROXY_OPT_MSS)
+ xt_xlate_add(xl, "mss %u ", info->mss);
+ if (info->options & XT_SYNPROXY_OPT_ECN)
+ xt_xlate_add(xl, "ecn ");
+
+ return 1;
+}
+
static struct xtables_target synproxy_tg_reg = {
.family = NFPROTO_UNSPEC,
.name = "SYNPROXY",
@@ -119,6 +141,7 @@ static struct xtables_target synproxy_tg_reg = {
.x6_parse = SYNPROXY_parse,
.x6_fcheck = SYNPROXY_check,
.x6_options = SYNPROXY_opts,
+ .xlate = SYNPROXY_xlate,
};
void _init(void)
diff --git a/extensions/libxt_SYNPROXY.txlate b/extensions/libxt_SYNPROXY.txlate
new file mode 100644
index 00000000..b347d3b7
--- /dev/null
+++ b/extensions/libxt_SYNPROXY.txlate
@@ -0,0 +1,2 @@
+iptables-translate -t mangle -A INPUT -i iifname -p tcp -m tcp --dport 80 -m state --state INVALID,UNTRACKED -j SYNPROXY --sack-perm --timestamp --wscale 7 --mss 1460
+nft add rule ip mangle INPUT iifname "iifname" tcp dport 80 ct state invalid,untracked counter synproxy sack-perm timestamp wscale 7 mss 1460
--
2.23.0
