Function to read IP address in dot format

Function to read IP address in dot format

[linux lover]

Hello,
          what is the function to read IP address in
kernel code as human readable dot quad format? IP
address are unsigned int's in ip.h file as
        __u32   saddr;
        __u32   daddr;
         In ip_build_xmit ip header gets IP addresses
from rtable struct as
iph->saddr=rt->rt_src;
iph->daddr=rt->rt_dst;
           Now if i want to know to which ip current
packet is being sent i am using printks but it prints
iph->saddr in int format not in user readable format.
how to do that?
regards,
linux_lover



		
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Re: Function to read IP address in dot format

[Randy.Dunlap]

On Sun, 10 Apr 2005 23:05:10 -0700 (PDT) linux lover wrote:

| 
| Hello,
|           what is the function to read IP address in
| kernel code as human readable dot quad format? IP
| address are unsigned int's in ip.h file as
|         __u32   saddr;
|         __u32   daddr;
|          In ip_build_xmit ip header gets IP addresses
| from rtable struct as
| iph->saddr=rt->rt_src;
| iph->daddr=rt->rt_dst;
|            Now if i want to know to which ip current
| packet is being sent i am using printks but it prints
| iph->saddr in int format not in user readable format.
| how to do that?

Look at the NIPQUAD() macro in include/linux/kernel.h
and at some example uses of it.

---
~Randy

Re: Function to read IP address in dot format

[Arnaldo Carvalho de Melo]

On Apr 11, 2005 3:05 AM, linux lover <linux_lover2004@yahoo.com> wrote:
> 
> Hello,
>           what is the function to read IP address in
> kernel code as human readable dot quad format? IP
> address are unsigned int's in ip.h file as
>         __u32   saddr;
>         __u32   daddr;
>          In ip_build_xmit ip header gets IP addresses
> from rtable struct as
> iph->saddr=rt->rt_src;
> iph->daddr=rt->rt_dst;
>            Now if i want to know to which ip current
> packet is being sent i am using printks but it prints
> iph->saddr in int format not in user readable format.
> how to do that?
> regards,

Use NIPQUAD, as in the example below:

        printk(KERN_DEBUG "dccp rx: packet=%s, "
                          "source=%u.%u.%u.%u@%d, "
                          "dest=%u.%u.%u.%u@%d\n",
               dccp_packet_name(dh->dccph_type),
               NIPQUAD(skb->nh.iph->saddr),
               ntohs(dh->dccph_sport),
               NIPQUAD(skb->nh.iph->daddr),
               ntohs(dh->dccph_dport));

- Arnaldo