multiple qemu networking together and with host (Linux host)

[Andrew Randrianasulu <randrianasulu%gmail.com@localhost>]

It was harder than I thought.

Main setup:

https://fo.ax/kali-kit/html_docs/86box.html

ip tuntap add dev tap-vde mode tap user "$USER"
ip link set 86box0 up
ip a add 10.1.0.1/16 dev tap-vde



vde_switch --mode 666 --numports 8 --tap tap-vde --mgmt
/tmp/vde.qemux0.mgmt --mgmtmode 666 -s /tmp/vde.qemux0 --daemon

Next, because I use wifi

sysctl -w net.ipv4.ip_forward=1

iptables -t nat -A POSTROUTING -s 10.1.0.1/16 -o wlan0 -j MASQUERADE

iptables -A FORWARD -i eth0 -o tap-vde -m state --state
RELATED,ESTABLISHED -j ACCEPT
iptables -A FORWARD -i 86box0 -o wlan0 -j ACCEPT

Install dhcpd (DHCP daemon)

config it like

cat /etc/dhcpd.conf
# dhcpd.conf
#
# Configuration file for ISC dhcpd (see 'man dhcpd.conf')
#
subnet 10.1.0.0 netmask 255.255.255.224 {
option routers 10.1.0.1 ;
range 10.1.0.10 10.1.0.15 ;
}

whole config (ifconfig -a)

root@slax:/dev/shm# ifconfig -a
eth7      Link encap:Ethernet  HWaddr A8:A1:59:9B:07:45
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:3 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:340797 errors:0 dropped:0 overruns:0 frame:0
          TX packets:340797 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:235555020 (224.6 Mb)  TX bytes:235555020 (224.6 Mb)

tap-vde   Link encap:Ethernet  HWaddr 86:2F:0D:6D:AC:96
          inet addr:10.1.0.1  Bcast:0.0.0.0  Mask:255.255.0.0
          inet6 addr: fe80::842f:dff:fe6d:ac96/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:4709 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4229 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:305415 (298.2 Kb)  TX bytes:260279 (254.1 Kb)

wlan0     Link encap:Ethernet  HWaddr 1C:BF:CE:C6:BE:00
          inet addr:192.168.1.104  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::1ebf:ceff:fec6:be00/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:3233241 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2858540 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1608028041 (1533.5 Mb)  TX bytes:845539101 (806.3 Mb)

IPTABLES config:

root@slax:/dev/shm# iptables -t nat -vnL
Chain PREROUTING (policy ACCEPT 1343 packets, 142K bytes)
 pkts bytes target     prot opt in     out     source               destination

Chain INPUT (policy ACCEPT 1031 packets, 45964 bytes)
 pkts bytes target     prot opt in     out     source               destination

Chain OUTPUT (policy ACCEPT 1736 packets, 297K bytes)
 pkts bytes target     prot opt in     out     source               destination

Chain POSTROUTING (policy ACCEPT 1736 packets, 297K bytes)
 pkts bytes target     prot opt in     out     source               destination
   17  1052 MASQUERADE  all  --  *      wlan0   10.1.0.0/16          0.0.0.0/0
    0     0 MASQUERADE  all  --  *      wlan0   10.1.0.0/16          0.0.0.0/0

=================

root@slax:/dev/shm# iptables  -vnL
Chain INPUT (policy ACCEPT 86261 packets, 23M bytes)
 pkts bytes target     prot opt in     out     source               destination

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination
   56  8221 ACCEPT     all  --  tap-vde wlan0   0.0.0.0/0            0.0.0.0/0
   66 29463 ACCEPT     all  --  wlan0  tap-vde  0.0.0.0/0
0.0.0.0/0            state RELATED,ESTABLISHED

Chain OUTPUT (policy ACCEPT 82010 packets, 16M bytes)
 pkts bytes target     prot opt in     out     source               destination

=======================

qemu 1;
qemu-system-sparc -hda
/mnt/zip/home/guest/QEMU/sparc-netbsd-15g-compressed-r1.qcow2   -smp 1
-accel tcg,thread=multi,tb-size=256 -M SS-20 -net
nic,macaddr=52:54:00:02:12:23 -net vde,sock=/tmp/vde.qemux0

qemu 2:
qemu-system-sparc -hda /dev/shm/sparc-netbsd-15g-compressed-r1.qcow2
-smp 1 -accel tcg,thread=multi,tb-size=256 -M SS-20 -m 256 -net
nic,macaddr=52:54:00:01:12:24 -net vde,sock=/tmp/vde.qemux0

Both qemu NetBSD machines should get ip 10.1.0.xx

You should be able to set /etc/resolv.conf to nameserver in your real
network (192.168.1.1 in my case - wifi router) and ping sites like
google.com etc

I was able to get nc (netcat) sending and receiving across two qemu's
and see host ftp/ssh services.

Next step is configuring distcc itself ;)

In theory vde2 should work on macos hosts, and may be freebsd ? Linux
is easy mode


It was bigger adventure than I initially hoped!