How to identify 6to4 and 6in4 tunnels

DISCUSSION zhuyj 2 participants 6 messages Jan 27, 2014 – Jan 28, 2014

Subsystems (2)

Networking Network drivers

lore

Share & tools

lore

zhuyj

author

2014-01-27 10:39 UTC #0 lore raw

Hi, Maintainers

In our scene, we will create the 6in4/6to4 tunnel firstly and need to check the tunnel type, secondly, we will configure the ip address on it. So, Could we have any way to get the actual tunnel for 6in4 and 6to4 from current linux version?

Both 6in4 and 6to4 have the same protocol “IPPROTO_IPV6” in Linux kernel. The only difference is the ip address on the tunnel. Can we distinguish them in Linux kernel?

Best Regards

Zhu Yanjun

Nicolas Dichtel

2014-01-27 12:59 UTC #1 lore raw

Quoted 9 lines · zhuyj

Hi, Maintainers
In our scene, we will create the 6in4/6to4 tunnel firstly and need to check the tunnel type, secondly, we will configure the ip address on it. So, Could we have any way to get the actual tunnel for 6in4 and 6to4 from current linux version?
Both 6in4 and 6to4 have the same protocol “IPPROTO_IPV6” in Linux kernel. The only difference is the ip address on the tunnel. Can we distinguish them in Linux kernel?

Just check the prefix, like it is done in check_6rd().

Regards,
Nicolas

zhuyj

author

2014-01-28 07:32 UTC #2 lore raw

Quoted 7 lines · Nicolas Dichtel

Quoted 6 lines · zhuyj
Hi, Maintainers
In our scene, we will create the 6in4/6to4 tunnel firstly and need to check the tunnel type, secondly, we will configure the ip address on it. So, Could we have any way to get the actual tunnel for 6in4 and 6to4 from current linux version?

Quoted 9 lines

Quoted 3 lines
Both 6in4 and 6to4 have the same protocol “IPPROTO_IPV6” in Linux kernel. The only difference is the ip address on the tunnel. Can we distinguish them in Linux kernel?
Just check the prefix, like it is done in check_6rd().
Regards,
Nicolas

Hi, Nicolas

Thanks for your reply. Maybe I can configure 6to4 tunnel by the following commands:

ip tunnel add tun6to4 mode sit remote any local 1.202.252.122 ttl 64 ip link set dev tun6to4 up
ip -6 addr add 2002:01ca:fc7a::0012:0225:2122/128 dev tun6to4 ip -6 route add 2000::/3 via ::192.88.99.1 dev tun6to4 metric 1

But the kernel can not identify the tunnel is 6to4 tunnel or 6in4 tunnel immediately. After the packets travel through this tunnel, the kernel can identify the type of the tunnel by check_6rd.

Is it right?

Best Regards!
Zhu Yanjun

zhuyj

author

2014-01-28 07:39 UTC #3 lore raw

Quoted 8 lines · zhuyj

Quoted 7 lines · Nicolas Dichtel
Quoted 6 lines · zhuyj
Hi, Maintainers
In our scene, we will create the 6in4/6to4 tunnel firstly and need to check the tunnel type, secondly, we will configure the ip address on it. So, Could we have any way to get the actual tunnel for 6in4 and 6to4 from current linux version?

Quoted 8 lines

Quoted 8 lines
Quoted 3 lines
Both 6in4 and 6to4 have the same protocol “IPPROTO_IPV6” in Linux kernel. The only difference is the ip address on the tunnel. Can we distinguish them in Linux kernel?
Just check the prefix, like it is done in check_6rd().
Regards,
Nicolas

Hi, Nicolas
Thanks for your reply. Maybe I can configure 6to4 tunnel by the following commands:

But the kernel can not identify the tunnel is 6to4 tunnel or 6in4 tunnel immediately. After the packets travel through this tunnel, the kernel can identify the type of the tunnel by check_6rd.

Is it right?

Best Regards!
Zhu Yanjun

zhuyj

author

2014-01-28 10:19 UTC #4 lore raw

Quoted 25 lines · zhuyj

Quoted 8 lines · zhuyj
Quoted 7 lines · Nicolas Dichtel
Quoted 6 lines · zhuyj
Hi, Maintainers
In our scene, we will create the 6in4/6to4 tunnel firstly and need to check the tunnel type, secondly, we will configure the ip address on it. So, Could we have any way to get the actual tunnel for 6in4 and 6to4 from current linux version?
Quoted 8 lines
Quoted 8 lines
Quoted 3 lines
Both 6in4 and 6to4 have the same protocol “IPPROTO_IPV6” in Linux kernel. The only difference is the ip address on the tunnel. Can we distinguish them in Linux kernel?
Just check the prefix, like it is done in check_6rd().
Regards,
Nicolas
Hi, Nicolas
Thanks for your reply. Maybe I can configure 6to4 tunnel by the following commands:
ip tunnel add tun6to4 mode sit remote any local 1.202.252.122 ttl 64 ip link set dev tun6to4 up
ip -6 addr add 2002:01ca:fc7a::0012:0225:2122/128 dev tun6to4 ip -6 route add 2000::/3 via ::192.88.99.1 dev tun6to4 metric 1

Quoted 8 lines

But the kernel can not identify the tunnel is 6to4 tunnel or 6in4 tunnel immediately. After the packets travel through this tunnel, the kernel can identify the type of the tunnel by check_6rd.
Is it right?
Best Regards!
Zhu Yanjun

Hi, David

I want to identify sit interface 6to4 or 6in4 with the following parameters.

include/uapi/linux/if_tunnel.h
...

struct ip_tunnel_parm {
        char                    name[IFNAMSIZ];
        int                     link;
        __be16                  i_flags;             <---------I want 
to use this variable to identify the type of sit interface. Can I?
        __be16                  o_flags;
        __be32                  i_key;
        __be32                  o_key;
        struct iphdr            iph;

};
...

Please comment on this ? Thanks a lot.

Best Regards!
Zhu Yanjun

Nicolas Dichtel

2014-01-28 15:20 UTC #5 lore raw

In reply to zhuyj

Quoted 26 lines · zhuyj

Quoted 9 lines · zhuyj
Quoted 8 lines · Nicolas Dichtel
Quoted 7 lines · zhuyj
Hi, Maintainers
In our scene, we will create the 6in4/6to4 tunnel firstly and need to check the tunnel type, secondly, we will configure the ip address on it. So, Could we have
any way to get the actual tunnel for 6in4 and 6to4 from current linux version?
Quoted 8 lines
Quoted 8 lines
Quoted 3 lines
Both 6in4 and 6to4 have the same protocol “IPPROTO_IPV6” in Linux kernel. The only difference is the ip address on the tunnel. Can we distinguish them in Linux kernel?
Just check the prefix, like it is done in check_6rd().
Regards,
Nicolas
Hi, Nicolas
Thanks for your reply. Maybe I can configure 6to4 tunnel by the following commands:
ip tunnel add tun6to4 mode sit remote any local 1.202.252.122 ttl 64 ip link set dev tun6to4 up
ip -6 addr add 2002:01ca:fc7a::0012:0225:2122/128 dev tun6to4 ip -6 route add 2000::/3 via ::192.88.99.1 dev tun6to4 metric 1

Quoted 5 lines

But the kernel can not identify the tunnel is 6to4 tunnel or 6in4 tunnel immediately. After the packets travel through this tunnel, the kernel can identify the type of the tunnel by check_6rd.
Is it right?

As soon as you have added the ipv6 addresses, you know that this tunnel is a 6to4 tunnel.
But what problem are you trying to solve?

Regards,
Nicolas