[LARTC] Getting "ip" command to work

[LARTC] Getting "ip" command to work

[David]

<PRE>I am looking to route packets through a specific address on the other
side of a couple of layers of IP Masquerading.  My understanding is I
need to use iproute for this (or at least that's the best way to get it
to work).  The trouble is, I can't get the program to do anything. 
Whenever I run a basic command such as &quot;ip link list&quot; I get &quot;Cannot send
dump request: Connection refused&quot;.  Networking is functional, and every
other networking command works as expected, including the standard
&quot;route&quot; command.

I'm running a Debian 2.2 system with the iproute package installed.  I
first tried with the included kernel, but it wouldn't work, so I rolled
my own (version 2.2.17) to see if that would let me use the command.  I
think I've turned everything required on:

Here's the network entries from the .config file for my current kernel:
[snip]
#
# Networking options
#
CONFIG_PACKET=y
CONFIG_NETLINK=y
CONFIG_RTNETLINK=y
CONFIG_NETLINK_DEV=y
CONFIG_FIREWALL=y
CONFIG_FILTER=y
CONFIG_UNIX=y
CONFIG_INET=y
# CONFIG_IP_MULTICAST is not set
CONFIG_IP_ADVANCED_ROUTER=y
CONFIG_RTNETLINK=y
CONFIG_NETLINK=y
CONFIG_IP_MULTIPLE_TABLES=y
# CONFIG_IP_ROUTE_MULTIPATH is not set
# CONFIG_IP_ROUTE_TOS is not set
CONFIG_IP_ROUTE_VERBOSE=y
CONFIG_IP_ROUTE_LARGE_TABLES=y
CONFIG_IP_ROUTE_NAT=y
# CONFIG_IP_PNP is not set
CONFIG_IP_FIREWALL=y
CONFIG_IP_FIREWALL_NETLINK=y
CONFIG_NETLINK_DEV=y
CONFIG_IP_ROUTE_FWMARK=y
CONFIG_IP_TRANSPARENT_PROXY=y
CONFIG_IP_MASQUERADE=y
CONFIG_IP_MASQUERADE_ICMP=y
CONFIG_IP_ROUTER=y
CONFIG_NET_IPIP=m
CONFIG_NET_IPGRE=m
CONFIG_IP_ALIAS=y
# CONFIG_SYN_COOKIES is not set
# CONFIG_INET_RARP is not set
CONFIG_SKB_LARGE=y
# CONFIG_IPX is not set
# CONFIG_ATALK is not set
[snip]

Can anyone help me figure out what I am missing?  Thank you very much.

-David Zoll


</PRE>

[LARTC] Getting "ip" command to work

[David]

<PRE>bert hubert wrote:
&gt;<i> 
</I>&gt;<i> On Thu, Oct 26, 2000 at 05:03:01PM -0400, David Zoll wrote:
</I>&gt;<i> 
</I>&gt;<i> &gt; I'm running a Debian 2.2 system with the iproute package installed.  I
</I>&gt;<i> &gt; first tried with the included kernel, but it wouldn't work, so I rolled
</I>&gt;<i> &gt; my own (version 2.2.17) to see if that would let me use the command.  I
</I>&gt;<i> &gt; think I've turned everything required on:
</I>&gt;<i> 
</I>&gt;<i> Did the included version give the exact same error?
</I>
I believe it did.

 
&gt;<i> This is very weird. Can you verify with 'uname -a' that you are running the
</I>&gt;<i> kernel you think you are running?
</I>
Yes I am.

 
&gt;<i> Attached is the output of 'strace /sbin/ip link list', which you can verify
</I>&gt;<i> with yours to see what is happening differently.
</I>[snip]
&gt;<i> 
</I>&gt;<i> execve(&quot;/sbin/ip&quot;, [&quot;/sbin/ip&quot;, &quot;link&quot;, &quot;list&quot;], [/* 30 vars */]) = 0
</I>
This line is &quot;execve(&quot;/sbin/ip&quot;, [&quot;/sbin/ip&quot;, &quot;link&quot;, &quot;list&quot;, &quot;3&quot;], [/*
20 vars */]) = 0&quot; for me.  I used the exact same syntax to run it.

The bulk of the rest is similar enough until the sendto line.  I get
handle number 3 rather than 4, sizes are different, and the contents of
buffers have minor differences.  It appears to bind to the socket it
eventually chokes on just fine.

&gt;<i> sendto(4, &quot;\24\0\0\0\22\0\1\3]\236\3709\0\0\0\0\21\0\0\0&quot;, 20, 0, {sin_family¯_NETLINK, {sa_family\x16, sa_data=&quot;\0\0\0\0\0\0\0\0\0\0\24\0\0\0&quot;}, 12) = 20
</I>
Here I get &quot;sendto(3,
&quot;\24\0\0\0\22\0\1\3\205\241\3709\0\0\0\0\21\0\0\0&quot;, 20, 0,
{sin_family¯_NETLINK, {sa_family\x16, sa_data=&quot;\0\0\0\0\0\0\0\0\0\0\2
4\0\0\0&quot;}, 12) = -1 ECONNREFUSED (Connection refused)&quot;

&gt;<i>From this point, it writes the error message and exits rather than
</I>continuing on with brk(0).

-David Zoll


</PRE>

[LARTC] Getting "ip" command to work

[bert]

<PRE>On Thu, Oct 26, 2000 at 05:03:01PM -0400, David Zoll wrote:

&gt;<i> I'm running a Debian 2.2 system with the iproute package installed.  I
</I>&gt;<i> first tried with the included kernel, but it wouldn't work, so I rolled
</I>&gt;<i> my own (version 2.2.17) to see if that would let me use the command.  I
</I>&gt;<i> think I've turned everything required on:
</I>
Did the included version give the exact same error?

This is very weird. Can you verify with 'uname -a' that you are running the
kernel you think you are running?

Attached is the output of 'strace /sbin/ip link list', which you can verify
with yours to see what is happening differently.

Regards,

bert hubert

execve(&quot;/sbin/ip&quot;, [&quot;/sbin/ip&quot;, &quot;link&quot;, &quot;list&quot;], [/* 30 vars */]) = 0
brk(0)                                  = 0x805dce4
open(&quot;/etc/ld.so.preload&quot;, O_RDONLY)    = -1 ENOENT (No such file or directory)
open(&quot;/etc/ld.so.cache&quot;, O_RDONLY)      = 4
fstat(4, {st_mode=S_IFREG|0644, st_size\x19370, ...}) = 0
old_mmap(NULL, 19370, PROT_READ, MAP_PRIVATE, 4, 0) = 0x40014000
close(4)                                = 0
open(&quot;/lib/libresolv.so.2&quot;, O_RDONLY)   = 4
fstat(4, {st_mode=S_IFREG|0644, st_sizeF576, ...}) = 0
read(4, &quot;\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0 \'\0\000&quot;..., 4096) = 4096
old_mmap(NULL, 59420, PROT_READ|PROT_EXEC, MAP_PRIVATE, 4, 0) = 0x40019000
mprotect(0x40024000, 14364, PROT_NONE)  = 0
old_mmap(0x40024000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED, 4, 0xa000) = 0x40024000
old_mmap(0x40026000, 6172, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x40026000
close(4)                                = 0
open(&quot;/lib/libc.so.6&quot;, O_RDONLY)        = 4
fstat(4, {st_mode=S_IFREG|0755, st_sizeˆ8596, ...}) = 0
read(4, &quot;\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\244\213&quot;..., 4096) = 4096
old_mmap(NULL, 902972, PROT_READ|PROT_EXEC, MAP_PRIVATE, 4, 0) = 0x40028000
mprotect(0x400fd000, 30524, PROT_NONE)  = 0
old_mmap(0x400fd000, 16384, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED, 4, 0xd4000) = 0x400fd000
old_mmap(0x40101000, 14140, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x40101000
close(4)                                = 0
munmap(0x40014000, 19370)               = 0
personality(PER_LINUX)                  = 0
getpid()                                = 32233
socket(PF_NETLINK, SOCK_RAW, 0)         = 4
bind(4, {sin_family¯_NETLINK, {sa_family\x16, sa_data=&quot;\0\0\0\0\0\0\0\0\0\0\205\234\0@&quot;}, 12) = 0
getsockname(4, {sin_family¯_NETLINK, {sa_family\x16, sa_data=&quot;\0\0\351}\0\0\0\0\0\0\205\234\0@&quot;}, [12]) = 0
time(NULL)                              = 972594780
sendto(4, &quot;\24\0\0\0\22\0\1\3]\236\3709\0\0\0\0\21\0\0\0&quot;, 20, 0, {sin_family¯_NETLINK, {sa_family\x16, sa_data=&quot;\0\0\0\0\0\0\0\0\0\0\24\0\0\0&quot;}, 12) = 20
recvmsg(4, {msg_name(12)={sin_family¯_NETLINK, {sa_family\x16, sa_data=&quot;\0\0\0\0\0\0\0\0\0\0\264\0\0\0&quot;}, msg_iov(1)=[{&quot;\264\0\0\0\20\0\2\0]\236\3709\351}\0\0\0\0\4\3\1\0\0\0&quot;..., 8192}], msg_controllen=0, msg_flags=0}, 0) = 368
brk(0)                                  = 0x805dce4
brk(0x805ddb4)                          = 0x805ddb4
brk(0x805e000)                          = 0x805e000
recvmsg(4, {msg_name(12)={sin_family¯_NETLINK, {sa_family\x16, sa_data=&quot;&amp;\301\0\0\0\0\0\0\0\0\24\0\0\0&quot;}, msg_iov(1)=[{&quot;\24\0\0\0\3\0\2\0]\236\3709\351}\0\0\0\0\0\0\1\0\0\0I\0&quot;..., 8192}], msg_controllen=0, msg_flags=0}, 0) = 20
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(3, 1), ...}) = 0
old_mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x40014000
ioctl(1, TCGETS, {B38400 opost isig icanon echo ...}) = 0
socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 5
ioctl(5, 0x8942, 0xbfffe9ac)            = 0
close(5)                                = 0
write(1, &quot;1: lo: &lt;LOOPBACK,UP&gt; mtu 16192 q&quot;..., 46) = 46
write(1, &quot;    link/loopback 00:00:00:00:00&quot;..., 58) = 58
socket(PF_INET, SOCK_STREAM, IPPROTO_IP) = 5
ioctl(5, 0x8942, 0xbfffe9ac)            = 0
close(5)                                = 0
write(1, &quot;2: eth0: &lt;BROADCAST,MULTICAST,UP&quot;..., 69) = 69
write(1, &quot;    link/ether 00:00:e8:58:b6:31&quot;..., 55) = 55
munmap(0x40014000, 4096)                = 0
_exit(0)                                = ?


-- 
PowerDNS                     Versatile DNS Services  
Trilab                       The Technology People   
'SYN! .. SYN|ACK! .. ACK!' - the mating call of the internet


</PRE>

[LARTC] Getting "ip" command to work

[David]

<PRE>
bert hubert wrote:
&gt;<i> 
</I>&gt;<i> On Thu, Oct 26, 2000 at 05:49:50PM -0400, David Zoll wrote:
</I>&gt;<i> 
</I>&gt;<i> &gt; The bulk of the rest is similar enough until the sendto line.  I get
</I>&gt;<i> &gt; handle number 3 rather than 4, sizes are different, and the contents of
</I>&gt;<i> 
</I>&gt;<i> The reason you get 3 is that I sent the output to a file, which took file
</I>&gt;<i> descriptor. Well, you've lost me here, try posting on the linux-kernel list.
</I>&gt;<i> I think something is broken.
</I>
My fault, your first instinct was the right one.  I wasn't running the
kernel version I thought I was.  Uname didn't give me enough info to see
that, but I noticed that lilo.conf wasn't set up the way I had expected
it, so it was still booting with the out-of-the-box Debian kernel.

IP is working now.

I'm planning to submit a wishlist item to Debian for a default kernel
that supports iproute2, unless someone has beat me to it.

Thanks alot for your help,
-David Zoll


</PRE>

[LARTC] Getting "ip" command to work

[bert]

<PRE>On Thu, Oct 26, 2000 at 05:49:50PM -0400, David Zoll wrote:

&gt;<i> The bulk of the rest is similar enough until the sendto line.  I get
</I>&gt;<i> handle number 3 rather than 4, sizes are different, and the contents of
</I>
The reason you get 3 is that I sent the output to a file, which took file
descriptor. Well, you've lost me here, try posting on the linux-kernel list.
I think something is broken.

Regards,

bert hubert

-- 
PowerDNS                     Versatile DNS Services  
Trilab                       The Technology People   
'SYN! .. SYN|ACK! .. ACK!' - the mating call of the internet


</PRE>