extensions: libip6t_MASQUERADE: Add translation to nft

Add translation for masquerade to nftables.

Examples:

$ sudo ip6tables-translate -t nat -A POSTROUTING -j MASQUERADE
nft add rule ip6 nat POSTROUTING counter masquerade

$ sudo ip6tables-translate -t nat -A POSTROUTING -p tcp -j MASQUERADE --to-ports 10
nft add rule ip6 nat POSTROUTING ip6 nexthdr tcp counter masquerade to :10

$ sudo ip6tables-translate -t nat -A POSTROUTING -p tcp -j MASQUERADE --to-ports 10-20 --random
nft add rule ip6 nat POSTROUTING ip6 nexthdr tcp counter masquerade to :10-20 random

Signed-off-by: Shivani Bhardwaj <shivanib134@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/extensions/libip6t_MASQUERADE.c b/extensions/libip6t_MASQUERADE.c
index eb9213efa089bc398da38d6b750eb714074d88f6..5a309ac9c03a612b55482ef39eee0ed5444d35f3 100644 (file)
--- a/extensions/libip6t_MASQUERADE.c
+++ b/extensions/libip6t_MASQUERADE.c
@@ -131,6 +131,27 @@ MASQUERADE_save(const void *ip, const struct xt_entry_target *target)
                printf(" --random");
 }
 
+static int
+MASQUERADE_xlate(const struct xt_entry_target *target,
+                struct xt_xlate *xl, int numeric)
+{
+       const struct nf_nat_range *r = (const void *)target->data;
+
+       xt_xlate_add(xl, "masquerade");
+
+       if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
+               xt_xlate_add(xl, " to :%hu", ntohs(r->min_proto.tcp.port));
+               if (r->max_proto.tcp.port != r->min_proto.tcp.port)
+                       xt_xlate_add(xl, "-%hu", ntohs(r->max_proto.tcp.port));
+       }
+
+       xt_xlate_add(xl, " ");
+       if (r->flags & NF_NAT_RANGE_PROTO_RANDOM)
+               xt_xlate_add(xl, "random ");
+
+       return 1;
+}
+
 static struct xtables_target masquerade_tg_reg = {
        .name           = "MASQUERADE",
        .version        = XTABLES_VERSION,
@@ -142,6 +163,7 @@ static struct xtables_target masquerade_tg_reg = {
        .print          = MASQUERADE_print,
        .save           = MASQUERADE_save,
        .x6_options     = MASQUERADE_opts,
+       .xlate          = MASQUERADE_xlate,
 };
 
 void _init(void)