Re: Error in print-ospf layout?

[Hannes Gredler <hannes () juniper net>]

tx, could you pls post a .pcap capture of that ospf packet
for more in-depth testing ?

..and on which architecure did you note the
endian error ?

/hannes

On Sat, Feb 28, 2004 at 12:57:22AM +0100, click wrote:
| Hi all,
| I tried some libnet's samples to sniffing an OSPFV2 HELLO pachet I saw 
| something strange in the endianless:
| 
| root@White-Dolphin:/home/click/libnet/sample# ./ospf_hello 192.168.0.1 
| 192.168.0.1 192.168.0.4
| libnet 1.1 OSPF Hello packet shaping[raw]
| Wrote 68 byte OSPF packet; check the wire.
| 
| Sniffing with tcpdump (last CVS version)
| 
| root@White-Dolphin:~/tcpdump# tcpdump -v -i any
| tcpdump: WARNING: Promiscuous mode not supported on the "any" device
| tcpdump: listening on any, link-type LINUX_SLL (Linux cooked), capture size 68 
| bytes
| 00:35:17.518403 IP (tos 0x0, ttl 254, id 101, offset 0, flags [DF], length: 
| 68) White-Dolphin.spine.org > White-Dolphin.spine.org: OSPFv2, Hello (1), 
| length: 48
|         Router-ID: 13.0.0.208, Area 0.238.255.192, Authentication Type: none 
| (0)
|         Options: [none] [|ospf]
| [snip]
| 
| Has you can see Router-ID and Area are printed in a wrong way.....
| the problem is at line 841 of tcpdump/printf-ospf.c for Router-ID field,
| and at line 845 for Area field.
| 
| I've patched temporarily print-ospf.c using intoa() and htonl() has you can 
| see in the .diff file attached with this mail.
| 
| With printf-ospf.c patched:
| 
| OSPFv2, Hello (1), length: 48
|         Router-ID: 208.0.0.13, Area 192.255.238.0, Authentication Type: none 
| (0)
|         Options: [none] [|ospf]
| 
| 
| Regards
| Valerio 'click' Genovese
| --
| http://www.spine-group.org
| 
| 

| --- print-ospf.c      2004-01-27 14:33:24.000000000 +0100
| +++ print-ospf-patch.c        2004-02-28 00:52:36.000000000 +0100
| @@ -838,11 +838,11 @@
|       dataend = bp + length;
|  
|       TCHECK(op->ospf_routerid);
| -        printf("\n\tRouter-ID: %s", ipaddr_string(&op->ospf_routerid));
| +        printf("\n\tRouter-ID: %s", intoa(htonl(op->ospf_routerid.s_addr)));
|  
|       TCHECK(op->ospf_areaid);
|       if (op->ospf_areaid.s_addr != 0)
| -             printf(", Area %s", ipaddr_string(&op->ospf_areaid));
| +             printf(", Area %s", intoa(htonl(op->ospf_areaid.s_addr)));
|       else
|               printf(", Backbone Area");
|  

-
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