From 5e4c54e81e9b39de0647c302aa463777e2298318 Mon Sep 17 00:00:00 2001 From: Shivani Bhardwaj Date: Tue, 29 Dec 2015 00:21:45 +0530 Subject: extensions: libipt_DNAT: Add translation to nft Add translation for target DNAT to nftables. Examples: $ sudo iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4 nft add rule ip nat prerouting oifname eth0 ip protocol tcp counter dnat 1.2.3.4 $ sudo iptables-translate -t nat -A prerouting -p tcp -d 15.45.23.67 --dport 80 -j DNAT --to-destination 192.168.1.1-192.168.1.10 nft add rule ip nat prerouting ip daddr 15.45.23.67 tcp dport 80 counter dnat 192.168.1.1-192.168.1.10 $ sudo iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4:1-1023 nft add rule ip nat prerouting oifname eth0 ip protocol tcp counter dnat 1.2.3.4:1-1023 $ sudo iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4 --random nft add rule ip nat prerouting oifname eth0 ip protocol tcp counter dnat 1.2.3.4 random $ sudo iptables-translate -t nat -A prerouting -p tcp -o eth0 -j DNAT --to-destination 1.2.3.4 --random --persistent nft add rule ip nat prerouting oifname eth0 ip protocol tcp counter dnat 1.2.3.4 random,persistent Signed-off-by: Shivani Bhardwaj Signed-off-by: Pablo Neira Ayuso --- extensions/libipt_DNAT.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/extensions/libipt_DNAT.c b/extensions/libipt_DNAT.c index ff187999..e5291418 100644 --- a/extensions/libipt_DNAT.c +++ b/extensions/libipt_DNAT.c @@ -242,6 +242,51 @@ static void DNAT_save(const void *ip, const struct xt_entry_target *target) } } +static void print_range_xlate(const struct nf_nat_ipv4_range *r, + struct xt_buf *buf) +{ + if (r->flags & NF_NAT_RANGE_MAP_IPS) { + struct in_addr a; + + a.s_addr = r->min_ip; + xt_buf_add(buf, "%s", xtables_ipaddr_to_numeric(&a)); + if (r->max_ip != r->min_ip) { + a.s_addr = r->max_ip; + xt_buf_add(buf, "-%s", xtables_ipaddr_to_numeric(&a)); + } + } + if (r->flags & NF_NAT_RANGE_PROTO_SPECIFIED) { + xt_buf_add(buf, ":%hu", ntohs(r->min.tcp.port)); + if (r->max.tcp.port != r->min.tcp.port) + xt_buf_add(buf, "-%hu", ntohs(r->max.tcp.port)); + } +} + +static int DNAT_xlate(const struct xt_entry_target *target, + struct xt_buf *buf, int numeric) +{ + const struct ipt_natinfo *info = (const void *)target; + unsigned int i = 0; + bool sep_need = false; + const char *sep = " "; + + for (i = 0; i < info->mr.rangesize; i++) { + xt_buf_add(buf, "dnat "); + print_range_xlate(&info->mr.range[i], buf); + if (info->mr.range[i].flags & NF_NAT_RANGE_PROTO_RANDOM) { + xt_buf_add(buf, " random"); + sep_need = true; + } + if (info->mr.range[i].flags & NF_NAT_RANGE_PERSISTENT) { + if (sep_need) + sep = ","; + xt_buf_add(buf, "%spersistent", sep); + } + } + + return 1; +} + static struct xtables_target dnat_tg_reg = { .name = "DNAT", .version = XTABLES_VERSION, @@ -254,6 +299,7 @@ static struct xtables_target dnat_tg_reg = { .print = DNAT_print, .save = DNAT_save, .x6_options = DNAT_opts, + .xlate = DNAT_xlate, }; void _init(void) -- cgit v1.2.3