From bcf59827f2a6ab966c3719f1c02fdd67f3780f82 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Fri, 3 Feb 2023 18:58:36 +0100 Subject: [PATCH] extensions: libebt_ip: Do not use 'ip dscp' for translation Converting from TOS field match to DSCP one is irreversible, so replay testing is not possible. Use a raw payload expression to produce something that translates 1:1 back into an 'ip' match. Fixes: 03ecffe6c2cc0 ("ebtables-compat: add initial translations") Signed-off-by: Phil Sutter (cherry picked from commit 744c56bda974caaa274318d2825b3e43b55bf145) Conflicts: extensions/libebt_ip.txlate -> Adjust to missing commit 09d63e818ae0d ("extensions: change expected output for new format"). --- extensions/libebt_ip.c | 4 ++-- extensions/libebt_ip.txlate | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/extensions/libebt_ip.c b/extensions/libebt_ip.c index acb9bfcdbbd9f..7b6fa4a2139d4 100644 --- a/extensions/libebt_ip.c +++ b/extensions/libebt_ip.c @@ -677,10 +677,10 @@ static int brip_xlate(struct xt_xlate *xl, brip_xlate_nh(xl, info, EBT_IP_DEST); if (info->bitmask & EBT_IP_TOS) { - xt_xlate_add(xl, "ip dscp "); + xt_xlate_add(xl, "@nh,8,8 "); if (info->invflags & EBT_IP_TOS) xt_xlate_add(xl, "!= "); - xt_xlate_add(xl, "0x%02x ", info->tos & 0x3f); /* remove ECN bits */ + xt_xlate_add(xl, "0x%02x ", info->tos); } if (info->bitmask & EBT_IP_PROTO) { struct protoent *pe; diff --git a/extensions/libebt_ip.txlate b/extensions/libebt_ip.txlate index b5882c342b047..5c766e1b743ea 100644 --- a/extensions/libebt_ip.txlate +++ b/extensions/libebt_ip.txlate @@ -5,7 +5,7 @@ ebtables-translate -I FORWARD -p ip --ip-dst 10.0.0.1 nft insert rule bridge filter FORWARD ip daddr 10.0.0.1 counter ebtables-translate -I OUTPUT 3 -p ip -o eth0 --ip-tos 0xff -nft insert rule bridge filter OUTPUT oifname "eth0" ip dscp 0x3f counter +nft insert rule bridge filter OUTPUT oifname "eth0" @nh,8,8 0xff counter ebtables-translate -A FORWARD -p ip --ip-proto tcp --ip-dport 22 nft add rule bridge filter FORWARD tcp dport 22 counter -- 2.40.0