[PATCH] netfilter: fix dependency issues between IPv6 defragmentation and ip6tables

[PATCH] netfilter: fix dependency issues between IPv6 defragmentation and ip6tables

[Liu Hua]

commit f6318e558806c925029dc101f14874be9f9fa78f fix some related issue
when ip6tables is enabled. But when IP6_NF_IPTABLES is disabled and
NETFILTER_XT_TARGET_TPROXY is enabled. We will meet build failure with
"net/built-in.o: In function `tproxy_tg_init':
net/netfilter/xt_TPROXY.c:588: undefined reference to `nf_defrag_ipv6_enable'
"
So this patch change the Kconfig as ipv4 does.

Signed-off-by: Liu Hua <sdu.liu@huawei.com>
---
 net/netfilter/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index f70e34a..34f54a8 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -865,7 +865,7 @@ config NETFILTER_XT_TARGET_TPROXY
 	depends on (IPV6 || IPV6=n)
 	depends on IP_NF_MANGLE
 	select NF_DEFRAG_IPV4
-	select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
+	select NF_DEFRAG_IPV6
 	help
 	  This option adds a `TPROXY' target, which is somewhat similar to
 	  REDIRECT.  It can only be used in the mangle table and is useful
-- 
1.9.1

Re: [PATCH] netfilter: fix dependency issues between IPv6 defragmentation and ip6tables

[Florian Westphal]

Liu Hua <sdu.liu@huawei.com> wrote:
> commit f6318e558806c925029dc101f14874be9f9fa78f fix some related issue
> when ip6tables is enabled. But when IP6_NF_IPTABLES is disabled and
> NETFILTER_XT_TARGET_TPROXY is enabled. We will meet build failure with
> "net/built-in.o: In function `tproxy_tg_init':
> net/netfilter/xt_TPROXY.c:588: undefined reference to `nf_defrag_ipv6_enable'
> "
> So this patch change the Kconfig as ipv4 does.
> --- a/net/netfilter/Kconfig
> +++ b/net/netfilter/Kconfig
> @@ -865,7 +865,7 @@ config NETFILTER_XT_TARGET_TPROXY
>  	depends on (IPV6 || IPV6=n)
>  	depends on IP_NF_MANGLE
>  	select NF_DEFRAG_IPV4
> -	select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
> +	select NF_DEFRAG_IPV6

If IP6_NF_IPTABLES is not set, why would we have to pick
up IPV6 defragmentation?

Without ip6tables, TPROXY cannot be used for ipv6; in fact;
xt_TPROXY should be built without ipv6 support in this case.

My guess is that you have TPROXY=y but DEFRAG_IPV6=m, but that
might warrant a better fix (xt_socket seems to have same issue).

Re: [PATCH] netfilter: fix dependency issues between IPv6 defragmentation and ip6tables

[liusdu]

On 2015年05月03日 19:07, Florian Westphal wrote:
> Liu Hua <sdu.liu@huawei.com> wrote:
>> commit f6318e558806c925029dc101f14874be9f9fa78f fix some related issue
>> when ip6tables is enabled. But when IP6_NF_IPTABLES is disabled and
>> NETFILTER_XT_TARGET_TPROXY is enabled. We will meet build failure with
>> "net/built-in.o: In function `tproxy_tg_init':
>> net/netfilter/xt_TPROXY.c:588: undefined reference to `nf_defrag_ipv6_enable'
>> "
>> So this patch change the Kconfig as ipv4 does.
>> --- a/net/netfilter/Kconfig
>> +++ b/net/netfilter/Kconfig
>> @@ -865,7 +865,7 @@ config NETFILTER_XT_TARGET_TPROXY
>>   	depends on (IPV6 || IPV6=n)
>>   	depends on IP_NF_MANGLE
>>   	select NF_DEFRAG_IPV4
>> -	select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
>> +	select NF_DEFRAG_IPV6
> IP6_NF_IPTABLES
> If IP6_NF_IPTABLES is not set, why would we have to pick
> up IPV6 defragmentation?
>
> Without ip6tables, TPROXY cannot be used for ipv6; in fact;
> xt_TPROXY should be built without ipv6 support in this case.
>
> My guess is that you have TPROXY=y but DEFRAG_IPV6=m, but that
> might warrant a better fix (xt_socket seems to have same issue).
Hi Florian,

Yes, It was exactly what I did.  Actually there is a macro to
determine whether we compile nf_defrag_ipv6_enable or not,
called XT_TPROXY_HAVE_IPV6, which will be set to 1 while
IP6_NF_IPTABLES=y or m.  With the patch below  we can
make the compiling pass. But I am not sure it is good enough
or not.

diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
index cca96ce..abbda64 100644
--- a/net/netfilter/xt_TPROXY.c
+++ b/net/netfilter/xt_TPROXY.c
@@ -24,7 +24,7 @@

  #include <net/netfilter/ipv4/nf_defrag_ipv4.h>

-#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
+#if IS_BUILTIN(CONFIG_IP6_NF_IPTABLES)
  #define XT_TPROXY_HAVE_IPV6 1
  #include <net/if_inet6.h>
  #include <net/addrconf.h>
diff --git a/net/netfilter/xt_socket.c b/net/netfilter/xt_socket.c
index e092cb0..239fccf 100644
--- a/net/netfilter/xt_socket.c
+++ b/net/netfilter/xt_socket.c
@@ -21,7 +21,7 @@
  #include <net/inet_sock.h>
  #include <net/netfilter/ipv4/nf_defrag_ipv4.h>

-#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
+#if IS_BUILTIN(CONFIG_IP6_NF_IPTABLES)
  #define XT_SOCKET_HAVE_IPV6 1
  #include <linux/netfilter_ipv6/ip6_tables.h>
  #include <net/inet6_hashtables.h>

Re: [PATCH] netfilter: fix dependency issues between IPv6 defragmentation and ip6tables

[Florian Westphal]

liusdu <liusdu@126.com> wrote:
> On 2015年05月03日 19:07, Florian Westphal wrote:
> >Liu Hua <sdu.liu@huawei.com> wrote:
> >>commit f6318e558806c925029dc101f14874be9f9fa78f fix some related issue
> >>when ip6tables is enabled. But when IP6_NF_IPTABLES is disabled and
> >>NETFILTER_XT_TARGET_TPROXY is enabled. We will meet build failure with
> >>"net/built-in.o: In function `tproxy_tg_init':
> >>net/netfilter/xt_TPROXY.c:588: undefined reference to `nf_defrag_ipv6_enable'
> >>"
> >>So this patch change the Kconfig as ipv4 does.
> >>--- a/net/netfilter/Kconfig
> >>+++ b/net/netfilter/Kconfig
> >>@@ -865,7 +865,7 @@ config NETFILTER_XT_TARGET_TPROXY
> >>  	depends on (IPV6 || IPV6=n)
> >>  	depends on IP_NF_MANGLE
> >>  	select NF_DEFRAG_IPV4
> >>-	select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
> >>+	select NF_DEFRAG_IPV6
> >IP6_NF_IPTABLES
> >If IP6_NF_IPTABLES is not set, why would we have to pick
> >up IPV6 defragmentation?
> >
> >Without ip6tables, TPROXY cannot be used for ipv6; in fact;
> >xt_TPROXY should be built without ipv6 support in this case.
> >
> >My guess is that you have TPROXY=y but DEFRAG_IPV6=m, but that
> >might warrant a better fix (xt_socket seems to have same issue).
> Hi Florian,
> 
> Yes, It was exactly what I did.  Actually there is a macro to
> determine whether we compile nf_defrag_ipv6_enable or not,
> called XT_TPROXY_HAVE_IPV6, which will be set to 1 while
> IP6_NF_IPTABLES=y or m.  With the patch below  we can
> make the compiling pass. But I am not sure it is good enough
> or not.
> diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
> index cca96ce..abbda64 100644
> --- a/net/netfilter/xt_TPROXY.c
> +++ b/net/netfilter/xt_TPROXY.c
> @@ -24,7 +24,7 @@
> 
>  #include <net/netfilter/ipv4/nf_defrag_ipv4.h>
> 
> -#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
> +#if IS_BUILTIN(CONFIG_IP6_NF_IPTABLES)

This means you need to set IP6_NF_IPTABLES=y, else TPROXY doesn't work
with ipv6.  I suggest to try and get Kconfig to force the needed
dependency (DEFRAG=y if TPROXY=y && DEFRAG=m if TPROXY=m).

Maybe this is enough (untested)

diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -863,6 +863,7 @@ config NETFILTER_XT_TARGET_TPROXY
        depends on NETFILTER_XTABLES
        depends on NETFILTER_ADVANCED
        depends on (IPV6 || IPV6=n)
+       depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
        depends on IP_NF_MANGLE
        select NF_DEFRAG_IPV4
        select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
@@ -1356,6 +1357,7 @@ config NETFILTER_XT_MATCH_SOCKET
        depends on NETFILTER_ADVANCED
        depends on !NF_CONNTRACK || NF_CONNTRACK
        depends on (IPV6 || IPV6=n)
+       depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
        select NF_DEFRAG_IPV4
        select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
        help

Re: [PATCH] netfilter: fix dependency issues between IPv6 defragmentation and ip6tables

[liusdu]

On 2015年05月04日 04:09, Florian Westphal wrote:
> liusdu <liusdu@126.com> wrote:
>> On 2015年05月03日 19:07, Florian Westphal wrote:
>>> Liu Hua <sdu.liu@huawei.com> wrote:
>>>> commit f6318e558806c925029dc101f14874be9f9fa78f fix some related issue
>>>> when ip6tables is enabled. But when IP6_NF_IPTABLES is disabled and
>>>> NETFILTER_XT_TARGET_TPROXY is enabled. We will meet build failure with
>>>> "net/built-in.o: In function `tproxy_tg_init':
>>>> net/netfilter/xt_TPROXY.c:588: undefined reference to `nf_defrag_ipv6_enable'
>>>> "
>>>> So this patch change the Kconfig as ipv4 does.
>>>> --- a/net/netfilter/Kconfig
>>>> +++ b/net/netfilter/Kconfig
>>>> @@ -865,7 +865,7 @@ config NETFILTER_XT_TARGET_TPROXY
>>>>   	depends on (IPV6 || IPV6=n)
>>>>   	depends on IP_NF_MANGLE
>>>>   	select NF_DEFRAG_IPV4
>>>> -	select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
>>>> +	select NF_DEFRAG_IPV6
>>> IP6_NF_IPTABLES
>>> If IP6_NF_IPTABLES is not set, why would we have to pick
>>> up IPV6 defragmentation?
>>>
>>> Without ip6tables, TPROXY cannot be used for ipv6; in fact;
>>> xt_TPROXY should be built without ipv6 support in this case.
>>>
>>> My guess is that you have TPROXY=y but DEFRAG_IPV6=m, but that
>>> might warrant a better fix (xt_socket seems to have same issue).
>> Hi Florian,
>>
>> Yes, It was exactly what I did.  Actually there is a macro to
>> determine whether we compile nf_defrag_ipv6_enable or not,
>> called XT_TPROXY_HAVE_IPV6, which will be set to 1 while
>> IP6_NF_IPTABLES=y or m.  With the patch below  we can
>> make the compiling pass. But I am not sure it is good enough
>> or not.
>> diff --git a/net/netfilter/xt_TPROXY.c b/net/netfilter/xt_TPROXY.c
>> index cca96ce..abbda64 100644
>> --- a/net/netfilter/xt_TPROXY.c
>> +++ b/net/netfilter/xt_TPROXY.c
>> @@ -24,7 +24,7 @@
>>
>>   #include <net/netfilter/ipv4/nf_defrag_ipv4.h>
>>
>> -#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES)
>> +#if IS_BUILTIN(CONFIG_IP6_NF_IPTABLES)
> This means you need to set IP6_NF_IPTABLES=y, else TPROXY doesn't work
> with ipv6.  I suggest to try and get Kconfig to force the needed
> dependency (DEFRAG=y if TPROXY=y && DEFRAG=m if TPROXY=m).
>
> Maybe this is enough (untested)
>
> diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
> --- a/net/netfilter/Kconfig
> +++ b/net/netfilter/Kconfig
> @@ -863,6 +863,7 @@ config NETFILTER_XT_TARGET_TPROXY
>          depends on NETFILTER_XTABLES
>          depends on NETFILTER_ADVANCED
>          depends on (IPV6 || IPV6=n)
> +       depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
>          depends on IP_NF_MANGLE
>          select NF_DEFRAG_IPV4
>          select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
> @@ -1356,6 +1357,7 @@ config NETFILTER_XT_MATCH_SOCKET
>          depends on NETFILTER_ADVANCED
>          depends on !NF_CONNTRACK || NF_CONNTRACK
>          depends on (IPV6 || IPV6=n)
> +       depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
>          select NF_DEFRAG_IPV4
>          select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
>          help
It works for me. With it DEFRAG, TPROXY and IP6_NF_IPTABLES are always  
compiled as
the same type. A better way to solve such dependency problem.

Since I only report this, and you solve it. So could you give a formal 
patch for this. I am a
beginner of linux network system and very glad to do the test for you.