[PATCH v2] extensions: libxt_NFQUEUE: Add translation to nft

[PATCH v2] extensions: libxt_NFQUEUE: Add translation to nft

[Shivani Bhardwaj]

Add translation for NF queue to nftables.

Examples:

$ sudo iptables-translate -t nat -A PREROUTING -p tcp --dport 80 -j NFQUEUE --queue-num 30
nft add rule ip nat PREROUTING tcp dport 80 counter queue num 30

$ sudo iptables-translate -A FORWARD -j NFQUEUE --queue-num 0 --queue-bypass -p TCP --sport 80
nft add rule ip filter FORWARD tcp sport 80 counter queue num 0 bypass

$ sudo iptables-translate -A FORWARD -j NFQUEUE --queue-bypass -p TCP --sport 80 --queue-balance 0:3 --queue-cpu-fanout
nft add rule ip filter FORWARD tcp sport 80 counter queue num 0-3 bypass,fanout

Signed-off-by: Shivani Bhardwaj <shivanib134@gmail.com>
---
Changes in v2:
	Fix the code for queue-balance

 extensions/libxt_NFQUEUE.c | 62 +++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 61 insertions(+), 1 deletion(-)

diff --git a/extensions/libxt_NFQUEUE.c b/extensions/libxt_NFQUEUE.c
index 0c86918..ea38f86 100644
--- a/extensions/libxt_NFQUEUE.c
+++ b/extensions/libxt_NFQUEUE.c
@@ -205,6 +205,62 @@ static void NFQUEUE_init_v1(struct xt_entry_target *t)
 	tinfo->queues_total = 1;
 }
 
+static int NFQUEUE_xlate(const struct xt_entry_target *target,
+			 struct xt_xlate *xl, int numeric)
+{
+	const struct xt_NFQ_info *tinfo =
+		(const struct xt_NFQ_info *)target->data;
+
+	xt_xlate_add(xl, "queue num %u ", tinfo->queuenum);
+
+	return 1;
+}
+
+static int NFQUEUE_xlate_v1(const struct xt_entry_target *target,
+			    struct xt_xlate *xl, int numeric)
+{
+	const struct xt_NFQ_info_v1 *tinfo = (const void *)target->data;
+	unsigned int last = tinfo->queues_total;
+
+	if (last > 1) {
+		last += tinfo->queuenum - 1;
+		xt_xlate_add(xl, "queue num %u-%u ", tinfo->queuenum, last);
+	} else {
+		xt_xlate_add(xl, "queue num %u ", tinfo->queuenum);
+	}
+
+	return 1;
+}
+
+bool sep_need = false;
+
+static int NFQUEUE_xlate_v2(const struct xt_entry_target *target,
+			    struct xt_xlate *xl, int numeric)
+{
+	const struct xt_NFQ_info_v2 *info = (void *) target->data;
+
+	NFQUEUE_xlate_v1(target, xl, numeric);
+
+	if (info->bypass & NFQ_FLAG_BYPASS) {
+		xt_xlate_add(xl, "bypass");
+		sep_need = true;
+	}
+
+	return 1;
+}
+
+static int NFQUEUE_xlate_v3(const struct xt_entry_target *target,
+			    struct xt_xlate *xl, int numeric)
+{
+	const struct xt_NFQ_info_v3 *info = (void *)target->data;
+
+	NFQUEUE_xlate_v2(target, xl, numeric);
+	if (info->flags & NFQ_FLAG_CPU_FANOUT)
+		xt_xlate_add(xl, "%sfanout ", sep_need ? "," : "");
+
+	return 1;
+}
+
 static struct xtables_target nfqueue_targets[] = {
 {
 	.family		= NFPROTO_UNSPEC,
@@ -216,7 +272,8 @@ static struct xtables_target nfqueue_targets[] = {
 	.print		= NFQUEUE_print,
 	.save		= NFQUEUE_save,
 	.x6_parse	= NFQUEUE_parse,
-	.x6_options	= NFQUEUE_opts
+	.x6_options	= NFQUEUE_opts,
+	.xlate		= NFQUEUE_xlate,
 },{
 	.family		= NFPROTO_UNSPEC,
 	.revision	= 1,
@@ -230,6 +287,7 @@ static struct xtables_target nfqueue_targets[] = {
 	.save		= NFQUEUE_save_v1,
 	.x6_parse	= NFQUEUE_parse_v1,
 	.x6_options	= NFQUEUE_opts,
+	.xlate		= NFQUEUE_xlate_v1,
 },{
 	.family		= NFPROTO_UNSPEC,
 	.revision	= 2,
@@ -243,6 +301,7 @@ static struct xtables_target nfqueue_targets[] = {
 	.save		= NFQUEUE_save_v2,
 	.x6_parse	= NFQUEUE_parse_v2,
 	.x6_options	= NFQUEUE_opts,
+	.xlate		= NFQUEUE_xlate_v2,
 },{
 	.family		= NFPROTO_UNSPEC,
 	.revision	= 3,
@@ -256,6 +315,7 @@ static struct xtables_target nfqueue_targets[] = {
 	.save		= NFQUEUE_save_v3,
 	.x6_parse	= NFQUEUE_parse_v3,
 	.x6_options	= NFQUEUE_opts,
+	.xlate		= NFQUEUE_xlate_v3,
 }
 };
 
-- 
1.9.1

Re: [PATCH v2] extensions: libxt_NFQUEUE: Add translation to nft

[Florian Westphal]

Shivani Bhardwaj <shivanib134@gmail.com> wrote:
> $ sudo iptables-translate -t nat -A PREROUTING -p tcp --dport 80 -j NFQUEUE --queue-num 30
> nft add rule ip nat PREROUTING tcp dport 80 counter queue num 30
> 
> $ sudo iptables-translate -A FORWARD -j NFQUEUE --queue-num 0 --queue-bypass -p TCP --sport 80
> nft add rule ip filter FORWARD tcp sport 80 counter queue num 0 bypass
> 
> $ sudo iptables-translate -A FORWARD -j NFQUEUE --queue-bypass -p TCP --sport 80 --queue-balance 0:3 --queue-cpu-fanout
> nft add rule ip filter FORWARD tcp sport 80 counter queue num 0-3 bypass,fanout

translation look correct, thanks!

> +bool sep_need = false;

Is this really needed?
If it is, please add static keyword too.

> +static int NFQUEUE_xlate_v2(const struct xt_entry_target *target,
> +			    struct xt_xlate *xl, int numeric)
> +{
> +	const struct xt_NFQ_info_v2 *info = (void *) target->data;
> +
> +	NFQUEUE_xlate_v1(target, xl, numeric);
> +
> +	if (info->bypass & NFQ_FLAG_BYPASS) {
> +		xt_xlate_add(xl, "bypass");
> +		sep_need = true;
> +	}
> +
> +	return 1;
> +}
> +
> +static int NFQUEUE_xlate_v3(const struct xt_entry_target *target,
> +			    struct xt_xlate *xl, int numeric)
> +{
> +	const struct xt_NFQ_info_v3 *info = (void *)target->data;
> +
> +	NFQUEUE_xlate_v2(target, xl, numeric);
> +	if (info->flags & NFQ_FLAG_CPU_FANOUT)
> +		xt_xlate_add(xl, "%sfanout ", sep_need ? "," : "");
> +

Seems this could be written similar to something like:

if (info->flags & NFQ_FLAG_CPU_FANOUT) {
	bool sep_needed = info->bypass & NFQ_FLAG_BYPASS;
	xt_xlate_add(xl, "%sfanout ", sep_need ? "," : "");
...

Re: [PATCH v2] extensions: libxt_NFQUEUE: Add translation to nft

[Shivani Bhardwaj]

On Sun, Feb 7, 2016 at 2:55 PM, Florian Westphal <fw@strlen.de> wrote:
> Shivani Bhardwaj <shivanib134@gmail.com> wrote:
>> $ sudo iptables-translate -t nat -A PREROUTING -p tcp --dport 80 -j NFQUEUE --queue-num 30
>> nft add rule ip nat PREROUTING tcp dport 80 counter queue num 30
>>
>> $ sudo iptables-translate -A FORWARD -j NFQUEUE --queue-num 0 --queue-bypass -p TCP --sport 80
>> nft add rule ip filter FORWARD tcp sport 80 counter queue num 0 bypass
>>
>> $ sudo iptables-translate -A FORWARD -j NFQUEUE --queue-bypass -p TCP --sport 80 --queue-balance 0:3 --queue-cpu-fanout
>> nft add rule ip filter FORWARD tcp sport 80 counter queue num 0-3 bypass,fanout
>
> translation look correct, thanks!
>
>> +bool sep_need = false;
>
> Is this really needed?
> If it is, please add static keyword too.
>

Done. Please check the new version of this patch.

>> +static int NFQUEUE_xlate_v2(const struct xt_entry_target *target,
>> +                         struct xt_xlate *xl, int numeric)
>> +{
>> +     const struct xt_NFQ_info_v2 *info = (void *) target->data;
>> +
>> +     NFQUEUE_xlate_v1(target, xl, numeric);
>> +
>> +     if (info->bypass & NFQ_FLAG_BYPASS) {
>> +             xt_xlate_add(xl, "bypass");
>> +             sep_need = true;
>> +     }
>> +
>> +     return 1;
>> +}
>> +
>> +static int NFQUEUE_xlate_v3(const struct xt_entry_target *target,
>> +                         struct xt_xlate *xl, int numeric)
>> +{
>> +     const struct xt_NFQ_info_v3 *info = (void *)target->data;
>> +
>> +     NFQUEUE_xlate_v2(target, xl, numeric);
>> +     if (info->flags & NFQ_FLAG_CPU_FANOUT)
>> +             xt_xlate_add(xl, "%sfanout ", sep_need ? "," : "");
>> +
>
> Seems this could be written similar to something like:
>
> if (info->flags & NFQ_FLAG_CPU_FANOUT) {
>         bool sep_needed = info->bypass & NFQ_FLAG_BYPASS;
>         xt_xlate_add(xl, "%sfanout ", sep_need ? "," : "");
> ...

The pointer info used in both the versions (of NFQUEUE_xlate) is for
different structures. Sadly, this doesn't work as v3 structure doesn't
have a member for bypass field.

Thanks a lot.

Re: [PATCH v2] extensions: libxt_NFQUEUE: Add translation to nft

[Florian Westphal]

Shivani Bhardwaj <shivanib134@gmail.com> wrote:
> On Sun, Feb 7, 2016 at 2:55 PM, Florian Westphal <fw@strlen.de> wrote:

> > Seems this could be written similar to something like:
> >
> > if (info->flags & NFQ_FLAG_CPU_FANOUT) {
> >         bool sep_needed = info->bypass & NFQ_FLAG_BYPASS;
> >         xt_xlate_add(xl, "%sfanout ", sep_need ? "," : "");
> > ...
> 
> The pointer info used in both the versions (of NFQUEUE_xlate) is for
> different structures. Sadly, this doesn't work as v3 structure doesn't
> have a member for bypass field.

Oh, right.  However bypass & flags overlap -- I think you could just use
info->flags & NFQ_FLAG_BYPASS.

If you look at NFQUEUE_parse_v3() it just calls NFQUEUE_parse_v2() with
the v3 structure.

Re: [PATCH v2] extensions: libxt_NFQUEUE: Add translation to nft

[Shivani Bhardwaj]

On Mon, Feb 8, 2016 at 2:59 PM, Florian Westphal <fw@strlen.de> wrote:
> Shivani Bhardwaj <shivanib134@gmail.com> wrote:
>> On Sun, Feb 7, 2016 at 2:55 PM, Florian Westphal <fw@strlen.de> wrote:
>
>> > Seems this could be written similar to something like:
>> >
>> > if (info->flags & NFQ_FLAG_CPU_FANOUT) {
>> >         bool sep_needed = info->bypass & NFQ_FLAG_BYPASS;
>> >         xt_xlate_add(xl, "%sfanout ", sep_need ? "," : "");
>> > ...
>>
>> The pointer info used in both the versions (of NFQUEUE_xlate) is for
>> different structures. Sadly, this doesn't work as v3 structure doesn't
>> have a member for bypass field.
>
> Oh, right.  However bypass & flags overlap -- I think you could just use
> info->flags & NFQ_FLAG_BYPASS.
>
> If you look at NFQUEUE_parse_v3() it just calls NFQUEUE_parse_v2() with
> the v3 structure.

Yes, the code looks better now. Thanks a lot, Florian.