[PATCHv2] extensions: libxt_cluster: Add translation to nft

[PATCHv2] extensions: libxt_cluster: Add translation to nft

[Shyam Saini]

Add translation for cluster match to nftables

$ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-node 1 --cluster-hash-seed
0xdeadbeef -j MARK --set-mark 0xffff
nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
0xffff

$ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-nodemask 1 --cluster-hash-seed
0xdeadbeef -j MARK --set-mark 0xffff
nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
0xffff

 --debug=netlink Result
ip mangle PREROUTING
  [ meta load iifname => reg 1 ]
  [ cmp eq reg 1 0x31687465 0x00000000 0x00000000 0x00000000 ]
  [ ct load src => reg 2 , dir original ]
  [ hash reg 1 = jhash(reg 2, 4, 0xdeadbeef) % mod 2 ]
  [ cmp eq reg 1 0x00000000 ]
  [ immediate reg 1 0x00000000 ]
  [ meta set pkttype with reg 1 ]
  [ counter pkts 0 bytes 0 ]
  [ immediate reg 1 0x0000ffff ]
  [ meta set mark with reg 1 ]

For Example:

If we have  total 2 nodes (i.e, --cluster-total-nodes is 2) in the cluster then
 modulus 2 = {0, 1}

For node 1 (--cluster-local-node 1)
	jhash ct original saddr mod 2 seed 0xdeadbeef eq 0

For  node 2 (--cluster-local-node 2)
	jhash ct original saddr mod 2 seed 0xdeadbeef eq 1

Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
---
 extensions/libxt_cluster.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/extensions/libxt_cluster.c b/extensions/libxt_cluster.c
index 3adff12..f2abd18 100644
--- a/extensions/libxt_cluster.c
+++ b/extensions/libxt_cluster.c
@@ -126,6 +126,16 @@ cluster_save(const void *ip, const struct xt_entry_match *match)
 		info->total_nodes, info->hash_seed);
 }
 
+static int cluster_xlate(struct xt_xlate *xl,
+		const struct xt_xlate_mt_params *params)
+{
+	const struct xt_cluster_match_info *info = (const struct xt_cluster_match_info *)params->match->data;
+
+	xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq 0 meta pkttype set host",
+			info->total_nodes, info->hash_seed);
+	return 1;
+
+}
+
 static struct xtables_match cluster_mt_reg = {
 	.family		= NFPROTO_UNSPEC,
 	.name		= "cluster",
@@ -138,6 +148,7 @@ static struct xtables_match cluster_mt_reg = {
 	.x6_parse	= cluster_parse,
 	.x6_fcheck	= cluster_check,
 	.x6_options	= cluster_opts,
+	.xlate		= cluster_xlate,
 };
 
 void _init(void)
-- 
1.9.1

Re: [PATCHv2] extensions: libxt_cluster: Add translation to nft

[Pablo Neira Ayuso]

On Tue, May 30, 2017 at 01:55:34PM +0530, Shyam Saini wrote:
> Add translation for cluster match to nftables
> 
> $ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-node 1 --cluster-hash-seed
> 0xdeadbeef -j MARK --set-mark 0xffff
> nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
> 0xffff
> 
> $ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-nodemask 1 --cluster-hash-seed
> 0xdeadbeef -j MARK --set-mark 0xffff
> nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
> 0xffff
> 
>  --debug=netlink Result
> ip mangle PREROUTING
>   [ meta load iifname => reg 1 ]
>   [ cmp eq reg 1 0x31687465 0x00000000 0x00000000 0x00000000 ]
>   [ ct load src => reg 2 , dir original ]
>   [ hash reg 1 = jhash(reg 2, 4, 0xdeadbeef) % mod 2 ]
>   [ cmp eq reg 1 0x00000000 ]
>   [ immediate reg 1 0x00000000 ]
>   [ meta set pkttype with reg 1 ]
>   [ counter pkts 0 bytes 0 ]
>   [ immediate reg 1 0x0000ffff ]
>   [ meta set mark with reg 1 ]
> 
> For Example:
> 
> If we have  total 2 nodes (i.e, --cluster-total-nodes is 2) in the cluster then
>  modulus 2 = {0, 1}
> 
> For node 1 (--cluster-local-node 1)
> 	jhash ct original saddr mod 2 seed 0xdeadbeef eq 0
> 
> For  node 2 (--cluster-local-node 2)
> 	jhash ct original saddr mod 2 seed 0xdeadbeef eq 1
> 
> Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
> ---
>  extensions/libxt_cluster.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/extensions/libxt_cluster.c b/extensions/libxt_cluster.c
> index 3adff12..f2abd18 100644
> --- a/extensions/libxt_cluster.c
> +++ b/extensions/libxt_cluster.c
> @@ -126,6 +126,16 @@ cluster_save(const void *ip, const struct xt_entry_match *match)
>  		info->total_nodes, info->hash_seed);
>  }
>  
> +static int cluster_xlate(struct xt_xlate *xl,
> +		const struct xt_xlate_mt_params *params)
> +{
> +	const struct xt_cluster_match_info *info = (const struct xt_cluster_match_info *)params->match->data;
> +
> +	xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq 0 meta pkttype set host",

This should use "eq %u" because:

	xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq %u meta pkttype set host",

Also check:

        ldd /path/to/your/iptables binary

and check what libraries you're suing, probably your iptables binary
using old ones.

Re: [PATCHv2] extensions: libxt_cluster: Add translation to nft

[Pablo Neira Ayuso]

On Tue, May 30, 2017 at 12:08:55PM +0200, Pablo Neira Ayuso wrote:
> On Tue, May 30, 2017 at 01:55:34PM +0530, Shyam Saini wrote:
> > Add translation for cluster match to nftables
> > 
> > $ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-node 1 --cluster-hash-seed
> > 0xdeadbeef -j MARK --set-mark 0xffff
> > nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
> > 0xffff
> > 
> > $ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-nodemask 1 --cluster-hash-seed
> > 0xdeadbeef -j MARK --set-mark 0xffff
> > nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
> > 0xffff
> > 
> >  --debug=netlink Result
> > ip mangle PREROUTING
> >   [ meta load iifname => reg 1 ]
> >   [ cmp eq reg 1 0x31687465 0x00000000 0x00000000 0x00000000 ]
> >   [ ct load src => reg 2 , dir original ]
> >   [ hash reg 1 = jhash(reg 2, 4, 0xdeadbeef) % mod 2 ]
> >   [ cmp eq reg 1 0x00000000 ]
> >   [ immediate reg 1 0x00000000 ]
> >   [ meta set pkttype with reg 1 ]
> >   [ counter pkts 0 bytes 0 ]
> >   [ immediate reg 1 0x0000ffff ]
> >   [ meta set mark with reg 1 ]
> > 
> > For Example:
> > 
> > If we have  total 2 nodes (i.e, --cluster-total-nodes is 2) in the cluster then
> >  modulus 2 = {0, 1}
> > 
> > For node 1 (--cluster-local-node 1)
> > 	jhash ct original saddr mod 2 seed 0xdeadbeef eq 0
> > 
> > For  node 2 (--cluster-local-node 2)
> > 	jhash ct original saddr mod 2 seed 0xdeadbeef eq 1
> > 
> > Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
> > ---
> >  extensions/libxt_cluster.c | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> > 
> > diff --git a/extensions/libxt_cluster.c b/extensions/libxt_cluster.c
> > index 3adff12..f2abd18 100644
> > --- a/extensions/libxt_cluster.c
> > +++ b/extensions/libxt_cluster.c
> > @@ -126,6 +126,16 @@ cluster_save(const void *ip, const struct xt_entry_match *match)
> >  		info->total_nodes, info->hash_seed);
> >  }
> >  
> > +static int cluster_xlate(struct xt_xlate *xl,
> > +		const struct xt_xlate_mt_params *params)
> > +{
> > +	const struct xt_cluster_match_info *info = (const struct xt_cluster_match_info *)params->match->data;
> > +
> > +	xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq 0 meta pkttype set host",
> 
> This should use "eq %u" because:
> 
> 	xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq %u meta pkttype set host",

Forget this I mentioned below, got mixed with another email to you.

What I'm telling here is, the "eq %u" should be used to translate
info->node_mask.

Note that info->node_mask is a bitmask, so you have to interpret this
accordingly from the translation.

Note that we have to support --cluster-local-nodemask too, you can
translate this using a set, ie.

jhash ct original saddr mod 4 seed 0x1234 { 0, 1 } meta pkttype set host

OK?

Re: [PATCHv2] extensions: libxt_cluster: Add translation to nft

[Shyam Saini]

On Tue, May 30, 2017 at 3:50 PM, Pablo Neira Ayuso <pablo@netfilter.org> wrote:
> On Tue, May 30, 2017 at 12:08:55PM +0200, Pablo Neira Ayuso wrote:
>> On Tue, May 30, 2017 at 01:55:34PM +0530, Shyam Saini wrote:
>> > Add translation for cluster match to nftables
>> >
>> > $ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-node 1 --cluster-hash-seed
>> > 0xdeadbeef -j MARK --set-mark 0xffff
>> > nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
>> > 0xffff
>> >
>> > $ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-nodemask 1 --cluster-hash-seed
>> > 0xdeadbeef -j MARK --set-mark 0xffff
>> > nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
>> > 0xffff
>> >
>> >  --debug=netlink Result
>> > ip mangle PREROUTING
>> >   [ meta load iifname => reg 1 ]
>> >   [ cmp eq reg 1 0x31687465 0x00000000 0x00000000 0x00000000 ]
>> >   [ ct load src => reg 2 , dir original ]
>> >   [ hash reg 1 = jhash(reg 2, 4, 0xdeadbeef) % mod 2 ]
>> >   [ cmp eq reg 1 0x00000000 ]
>> >   [ immediate reg 1 0x00000000 ]
>> >   [ meta set pkttype with reg 1 ]
>> >   [ counter pkts 0 bytes 0 ]
>> >   [ immediate reg 1 0x0000ffff ]
>> >   [ meta set mark with reg 1 ]
>> >
>> > For Example:
>> >
>> > If we have  total 2 nodes (i.e, --cluster-total-nodes is 2) in the cluster then
>> >  modulus 2 = {0, 1}
>> >
>> > For node 1 (--cluster-local-node 1)
>> >     jhash ct original saddr mod 2 seed 0xdeadbeef eq 0
>> >
>> > For  node 2 (--cluster-local-node 2)
>> >     jhash ct original saddr mod 2 seed 0xdeadbeef eq 1
>> >
>> > Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
>> > ---
>> >  extensions/libxt_cluster.c | 11 +++++++++++
>> >  1 file changed, 11 insertions(+)
>> >
>> > diff --git a/extensions/libxt_cluster.c b/extensions/libxt_cluster.c
>> > index 3adff12..f2abd18 100644
>> > --- a/extensions/libxt_cluster.c
>> > +++ b/extensions/libxt_cluster.c
>> > @@ -126,6 +126,16 @@ cluster_save(const void *ip, const struct xt_entry_match *match)
>> >             info->total_nodes, info->hash_seed);
>> >  }
>> >
>> > +static int cluster_xlate(struct xt_xlate *xl,
>> > +           const struct xt_xlate_mt_params *params)
>> > +{
>> > +   const struct xt_cluster_match_info *info = (const struct xt_cluster_match_info *)params->match->data;
>> > +
>> > +   xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq 0 meta pkttype set host",
>>
>> This should use "eq %u" because:
>>
>>       xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq %u meta pkttype set host",
>
> Forget this I mentioned below, got mixed with another email to you.
>
> What I'm telling here is, the "eq %u" should be used to translate
> info->node_mask.
>
> Note that info->node_mask is a bitmask, so you have to interpret this
> accordingly from the translation.

by this you mean, we have to take bitwise AND with generated jhash?

http://elixir.free-electrons.com/linux/latest/source/net/netfilter/xt_cluster.c#L132


> Note that we have to support --cluster-local-nodemask too, you can
> translate this using a set, ie.
>
> jhash ct original saddr mod 4 seed 0x1234 { 0, 1 } meta pkttype set host
>

Translation should print set of node id depending on the number of nodes.
For example for total_nodes = 4, it should print
jhash ct original saddr mod 4 seed 0x1234 { 0, 1, 2, 3 } meta pkttype set host
Right?

> OK?

Re: [PATCHv2] extensions: libxt_cluster: Add translation to nft

[Pablo Neira Ayuso]

On Tue, May 30, 2017 at 08:47:09PM +0530, Shyam Saini wrote:
> On Tue, May 30, 2017 at 3:50 PM, Pablo Neira Ayuso <pablo@netfilter.org> wrote:
> > On Tue, May 30, 2017 at 12:08:55PM +0200, Pablo Neira Ayuso wrote:
> >> On Tue, May 30, 2017 at 01:55:34PM +0530, Shyam Saini wrote:
> >> > Add translation for cluster match to nftables
> >> >
> >> > $ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-node 1 --cluster-hash-seed
> >> > 0xdeadbeef -j MARK --set-mark 0xffff
> >> > nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
> >> > 0xffff
> >> >
> >> > $ sudo iptables-translate -A PREROUTING -t mangle -i eth1 -m cluster --cluster-total-nodes 2 --cluster-local-nodemask 1 --cluster-hash-seed
> >> > 0xdeadbeef -j MARK --set-mark 0xffff
> >> > nft add rule ip mangle PREROUTING iifname eth1 jhash ct original saddr mod 2 seed 0xdeadbeef eq 0 meta pkttype set host counter meta mark set
> >> > 0xffff
> >> >
> >> >  --debug=netlink Result
> >> > ip mangle PREROUTING
> >> >   [ meta load iifname => reg 1 ]
> >> >   [ cmp eq reg 1 0x31687465 0x00000000 0x00000000 0x00000000 ]
> >> >   [ ct load src => reg 2 , dir original ]
> >> >   [ hash reg 1 = jhash(reg 2, 4, 0xdeadbeef) % mod 2 ]
> >> >   [ cmp eq reg 1 0x00000000 ]
> >> >   [ immediate reg 1 0x00000000 ]
> >> >   [ meta set pkttype with reg 1 ]
> >> >   [ counter pkts 0 bytes 0 ]
> >> >   [ immediate reg 1 0x0000ffff ]
> >> >   [ meta set mark with reg 1 ]
> >> >
> >> > For Example:
> >> >
> >> > If we have  total 2 nodes (i.e, --cluster-total-nodes is 2) in the cluster then
> >> >  modulus 2 = {0, 1}
> >> >
> >> > For node 1 (--cluster-local-node 1)
> >> >     jhash ct original saddr mod 2 seed 0xdeadbeef eq 0
> >> >
> >> > For  node 2 (--cluster-local-node 2)
> >> >     jhash ct original saddr mod 2 seed 0xdeadbeef eq 1
> >> >
> >> > Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
> >> > ---
> >> >  extensions/libxt_cluster.c | 11 +++++++++++
> >> >  1 file changed, 11 insertions(+)
> >> >
> >> > diff --git a/extensions/libxt_cluster.c b/extensions/libxt_cluster.c
> >> > index 3adff12..f2abd18 100644
> >> > --- a/extensions/libxt_cluster.c
> >> > +++ b/extensions/libxt_cluster.c
> >> > @@ -126,6 +126,16 @@ cluster_save(const void *ip, const struct xt_entry_match *match)
> >> >             info->total_nodes, info->hash_seed);
> >> >  }
> >> >
> >> > +static int cluster_xlate(struct xt_xlate *xl,
> >> > +           const struct xt_xlate_mt_params *params)
> >> > +{
> >> > +   const struct xt_cluster_match_info *info = (const struct xt_cluster_match_info *)params->match->data;
> >> > +
> >> > +   xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq 0 meta pkttype set host",
> >>
> >> This should use "eq %u" because:
> >>
> >>       xt_xlate_add(xl, "jhash ct original saddr mod %u seed 0x%08x eq %u meta pkttype set host",
> >
> > Forget this I mentioned below, got mixed with another email to you.
> >
> > What I'm telling here is, the "eq %u" should be used to translate
> > info->node_mask.
> >
> > Note that info->node_mask is a bitmask, so you have to interpret this
> > accordingly from the translation.
> 
> by this you mean, we have to take bitwise AND with generated jhash?
> 
> http://elixir.free-electrons.com/linux/latest/source/net/netfilter/xt_cluster.c#L132

No. I mean, you have to extract from the bitmask the node number, ie.

int i, k = 0;

for (i = 0; i < 32; i++) {
        if (info->node_mask & (1 << i)) {
                if (!needs_set) {
                        printf("{ ");
                        needs_set = true;
                }
                if (k)
                        printf(", ");

                printf("%u", i);
                k++;
        }
        if (needs_set)
                printf("}");
}

Something like this... not even compile tested.

> > Note that we have to support --cluster-local-nodemask too, you can
> > translate this using a set, ie.
> >
> > jhash ct original saddr mod 4 seed 0x1234 { 0, 1 } meta pkttype set host
> >
> 
> Translation should print set of node id depending on the number of nodes.
> For example for total_nodes = 4, it should print
> jhash ct original saddr mod 4 seed 0x1234 { 0, 1, 2, 3 } meta pkttype set host
> Right?

If there is a single node in the bitmask, then you just print:

[a] jhash ct original saddr mod 4 seed 0x1234 eq 3 meta pkttype set host

if rhere are several node in the bitmask, then, eg.

[b] jhash ct original saddr mod 4 seed 0x1234 eq { 0, 1, 3 } meta pkttype set host

You need to do some preprocessing on info->node_mask to know if you
need [a] or [b].