| Message ID | 20160602165756.GA21013@sonyv |
|---|---|
| State | Changes Requested |
| Delegated to: | Pablo Neira |
| Headers | show |
On Thu, Jun 02, 2016 at 06:57:58PM +0200, Laura Garcia Liebana wrote: > Add translation for frag to nftables. Not supported yet in nft: fraglen, > fragfirst and fraglast. You can provide translations for fragfirst and fraglast. '--fragfirst' is actually frag-off 0. and '--fraglast' is more-fragments 1. Note that because there is no 1:1 mapping, it doesn't mean you can translate things. And regarding --fraglen, if you look at iptables/extensions/libip6t_frag.c, you'll see: case O_FRAGLEN: /* * As of Linux 3.0, the kernel does not check for * fraglen at all. */ if (cb->invert) fraginfo->invflags |= IP6T_FRAG_INV_LEN; fraginfo->flags |= IP6T_FRAG_LEN; break; Then, browsing: http://lxr.free-electrons.com/source/net/ipv6/netfilter/ip6t_frag.c shows no references to IP6T_FRAG_LEN in the kernel, so this confirms this option was already deprecated time ago and the comment in the iptables source code is correct. Please, respin and send a v2 including this useful information on the commit message so we keep this in the record. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/extensions/libip6t_frag.c b/extensions/libip6t_frag.c index 023df62..00ba00f 100644 --- a/extensions/libip6t_frag.c +++ b/extensions/libip6t_frag.c @@ -173,6 +173,36 @@ static void frag_save(const void *ip, const struct xt_entry_match *match) printf(" --fraglast"); } +static int frag_xlate(const void *ip, const struct xt_entry_match *match, + struct xt_xlate *xl, int numeric) +{ + const struct ip6t_frag *fraginfo = (struct ip6t_frag *)match->data; + + if ((fraginfo->flags & IP6T_FRAG_LEN) || + (fraginfo->flags & IP6T_FRAG_FST) || + (fraginfo->flags & IP6T_FRAG_NMF)) { + return 0; + } + + if (!(fraginfo->ids[0] == 0 && fraginfo->ids[1] == 0xFFFFFFFF)) { + xt_xlate_add(xl, "frag id %s", + (fraginfo->invflags & IP6T_FRAG_INV_IDS) ? "!= " : ""); + if (fraginfo->ids[0] != fraginfo->ids[1]) + xt_xlate_add(xl, "%u-%u ", fraginfo->ids[0], + fraginfo->ids[1]); + else + xt_xlate_add(xl, "%u ", fraginfo->ids[0]); + } + + if (fraginfo->flags & IP6T_FRAG_RES) + xt_xlate_add(xl, "frag reserved 1 "); + + if (fraginfo->flags & IP6T_FRAG_MF) + xt_xlate_add(xl, "frag more-fragments 1 "); + + return 1; +} + static struct xtables_match frag_mt6_reg = { .name = "frag", .version = XTABLES_VERSION, @@ -185,6 +215,7 @@ static struct xtables_match frag_mt6_reg = { .save = frag_save, .x6_parse = frag_parse, .x6_options = frag_opts, + .xlate = frag_xlate, }; void
Add translation for frag to nftables. Not supported yet in nft: fraglen, fragfirst and fraglast. Examples: $ sudo iptables-translate -t filter -A INPUT -m frag --fragid 100:200 -j ACCEPT nft add rule ip6 filter INPUT frag id 100-200 counter accept $ sudo iptables-translate -t filter -A INPUT -m frag --fragid 100 --fragres --fragmore -j ACCEPT nft add rule ip6 filter INPUT frag id 100 frag reserved 1 frag more-fragments 1 counter accept $ sudo iptables-translate -t filter -A INPUT -m frag ! --fragid 100:200 -j ACCEPT nft add rule ip6 filter INPUT frag id != 100-200 counter accept Signed-off-by: Laura Garcia Liebana <nevola@gmail.com> --- extensions/libip6t_frag.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+)