extensions: libip6t_hbh: Add translation to nft

Add translation for Hop-By-Hop header to nftables. Hbh options are not
supported yet in nft.

$ sudo ip6tables-translate -t filter -A INPUT -m hbh --hbh-len 22
nft add rule ip6 filter INPUT hbh hdrlength 22 counter

$ sudo ip6tables-translate -t filter -A INPUT -m hbh ! --hbh-len 22
nft add rule ip6 filter INPUT hbh hdrlength != 22 counter

Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/extensions/libip6t_hbh.c b/extensions/libip6t_hbh.c
index c0389ed8bafdedd8e641067209e6e1a59893051f..416681d26c09ca34679c9d2f7ea595ca75f12eec 100644 (file)
--- a/extensions/libip6t_hbh.c
+++ b/extensions/libip6t_hbh.c
@@ -164,6 +164,22 @@ static void hbh_save(const void *ip, const struct xt_entry_match *match)
        print_options(optinfo->optsnr, (uint16_t *)optinfo->opts);
 }
 
+static int hbh_xlate(const void *ip, const struct xt_entry_match *match,
+                    struct xt_xlate *xl, int numeric)
+{
+       const struct ip6t_opts *optinfo = (struct ip6t_opts *)match->data;
+
+       if (!(optinfo->flags & IP6T_OPTS_LEN) ||
+           (optinfo->flags & IP6T_OPTS_OPTS))
+               return 0;
+
+       xt_xlate_add(xl, "hbh hdrlength %s%u ",
+                    (optinfo->invflags & IP6T_OPTS_INV_LEN) ? "!= " : "",
+                    optinfo->hdrlen);
+
+       return 1;
+}
+
 static struct xtables_match hbh_mt6_reg = {
        .name           = "hbh",
        .version        = XTABLES_VERSION,
@@ -175,6 +191,7 @@ static struct xtables_match hbh_mt6_reg = {
        .save           = hbh_save,
        .x6_parse       = hbh_parse,
        .x6_options     = hbh_opts,
+       .xlate          = hbh_xlate,
 };
 
 void