[ovs-dev] [PATCH] tests: Add gre test that doesn't requiring Linux gre module

Wed Jul 11 23:22:13 UTC 2018

Hi William,

Thanks for the test. I will do.

Best,
Yifeng

On Wed, Jul 11, 2018 at 4:19 PM, William Tu <u9012063 at gmail.com> wrote:

> Thanks for the patch.
>
> On Tue, Jul 10, 2018 at 12:24 PM, Yifeng Sun <pkusunyifeng at gmail.com>
> wrote:
> > Currently check-kmod's gre test is broken on certain kernel
> > versions where ovs's gre module conflits with kernel's gre
> > module. But at the same time, present gre test depends on
> > Linux gre module to setup gre port.
> >
> > This patch repairs the gre test by completely removing the
> > dependancy of kernel's gre module and emulating a virtual
> > Linux gre port that sends out arp and icmp packets.
> >
> > Suggested-by: William Tu <u9012063 at gmail.com>
> > Signed-off-by: Yifeng Sun <pkusunyifeng at gmail.com>
> > ---
> >  tests/system-common-macros.at | 13 +++++++++
> >  tests/system-traffic.at       | 67 ++++++++++++++++++++++++++++++
> +++++++++++++
> >  2 files changed, 80 insertions(+)
> >
> > diff --git a/tests/system-common-macros.at b/tests/system-common-macros.
> at
> > index 64bf5ec63ab4..7b841250c383 100644
> > --- a/tests/system-common-macros.at
> > +++ b/tests/system-common-macros.at
> > @@ -329,3 +329,16 @@ m4_define([OVS_CHECK_IPROUTE_ENCAP],
> >  # OVS_CHECK_CT_CLEAR()
> >  m4_define([OVS_CHECK_CT_CLEAR],
> >      [AT_SKIP_IF([! grep -q "Datapath supports ct_clear action"
> ovs-vswitchd.log])])
> > +
> > +# GEN_ICMP_DATA([start], [len])
> > +#
> > +# Generate space-separated ICMP data that is acceptable to
> tests/sendpkt.py.
> > +m4_define([GEN_ICMP_DATA],
> > +    [[
> > +      ICMP_DATA=""
> > +      for (( n=0; n<$2; n++ )); do
> > +          ICMP_DATA="${ICMP_DATA} $(printf %x $((($1+n) % 256)))"
> > +      done
> > +      echo "$ICMP_DATA"
> > +    ]]
> > +)
> > diff --git a/tests/system-traffic.at b/tests/system-traffic.at
> > index 519b234bb16b..37421ed1e78a 100644
> > --- a/tests/system-traffic.at
> > +++ b/tests/system-traffic.at
> > @@ -339,6 +339,73 @@ NS_CHECK_EXEC([at_ns0], [ping -s 3200 -q -c 3 -i
> 0.3 -w 2 10.1.1.100 | FORMAT_PI
> >  OVS_TRAFFIC_VSWITCHD_STOP
> >  AT_CLEANUP
> >
> > +AT_SETUP([datapath - ping over gre tunnel by simulated packets])
> > +OVS_CHECK_GRE()
> > +
> > +OVS_TRAFFIC_VSWITCHD_START()
> > +AT_CHECK([ovs-vsctl -- set bridge br0 other-config:hwaddr=\"f2:ff:
> 00:00:00:01\"])
> > +ADD_BR([br-underlay], [set bridge br-underlay
> other-config:hwaddr=\"f2:ff:00:00:00:02\"])
> > +
> > +AT_CHECK([ovs-ofctl add-flow br0 "actions=normal"])
> > +AT_CHECK([ovs-ofctl add-flow br-underlay "actions=normal"])
> > +
> > +ADD_NAMESPACES(at_ns0)
> > +
> > +dnl Set up underlay link from host into the namespace using veth pair.
> > +ADD_VETH(p0, at_ns0, br-underlay, "172.31.1.1/24", f2:ff:00:00:00:03)
> > +AT_CHECK([ip addr add dev br-underlay "172.31.1.100/24"])
> > +AT_CHECK([ip link set dev br-underlay up])
> > +
> > +dnl Set up tunnel endpoints on OVS outside the namespace.
> > +ADD_OVS_TUNNEL([gre], [br0], [at_gre0], [172.31.1.1], [10.1.1.100/24])
> > +
> > +ip netns exec at_ns0 tcpdump -U -i p0 -w p0.pcap &
>
> maybe you can add a filter here to reduce the packets counts in p0.pcap
> below you only egrep ip packet, or gre packet, so you can just
> "tcpdump -w p0.pcap proto GRE"
>
>
> > +
> > +dnl First, check the underlay.
> > +NS_CHECK_EXEC([at_ns0], [ping -q -c 3 -i 0.3 -w 2 172.31.1.100 |
> FORMAT_PING], [0], [dnl
> > +3 packets transmitted, 3 received, 0% packet loss, time 0ms
> > +])
> > +
> > +dnl Okay, now we don't actually add the port as below, instead, we
> > +dnl emulate it. Suppose its mac address is f2:ff:00:00:00:04.
> > +dnl ADD_NATIVE_TUNNEL([gretap], [ns_gre0], [at_ns0], [172.31.1.100], [
> 10.1.1.1/24])
> > +
> > +dnl Okay, now send out an arp request from 10.1.1.1 for 10.1.1.100 in
> gre.
> > +NS_CHECK_EXEC([at_ns0], [$PYTHON $srcdir/sendpkt.py p0 f2 ff 00 00 00
> 02 f2 ff 00 00 00 03 08 00 45 00 00 42 ec 2c 40 00 40 2f f3 bc ac 1f 01 01
> ac 1f 01 64 00 00 65 58 ff ff ff ff ff ff f2 ff 00 00 00 04 08 06 00 01 08
> 00 06 04 00 01 f2 ff 00 00 00 04 0a 01 01 01 00 00 00 00 00 00 0a 01 01 64
> > /dev/null])
> > +
> > +sleep 1
>
> Is it possible to use OVS_WAIT_UNTIL macro?
>
> > +AT_CHECK([tcpdump -xx -r p0.pcap 2>&1 | egrep "IP 172.31.1.100 >
> 172.31.1.1: GREv0, length 46: ARP, Reply 10.1.1.100 is-at
> f2:ff:00:00:00:01 .* length 28" 2>&1 1>/dev/null])
> > +
> > +dnl Oaky, now check the overlay by sending out raw icmp packets of
> > +dnl different sizes in gre protocol.
> > +
> > +dnl First, send the packet that emulates
> > +dnl `ip netns exec at_ns0 ping 10.1.1.100`
> > +NS_CHECK_EXEC([at_ns0], [$PYTHON $srcdir/sendpkt.py p0 f2 ff 00 00 00
> 02 f2 ff 00 00 00 03 08 00 45 00 00 7a ec 8e 40 00 40 2f f3 22 ac 1f 01 01
> ac 1f 01 64 00 00 65 58 f2 ff 00 00 00 01 f2 ff 00 00 00 04 08 00 45 00 00
> 54 54 8f 40 00 40 01 cf b3 0a 01 01 01 0a 01 01 64 08 00 e6 e8 29 27 00 03
> e1 a3 43 5b 00 00 00 00 ff 1a 05 00 00 00 00 00 $(GEN_ICMP_DATA(16, 40)) >
> /dev/null])
> > +
> > +sleep 1
> > +AT_CHECK([tcpdump -xx -r p0.pcap 2>&1 | egrep "IP 172.31.1.100 >
> 172.31.1.1: GREv0, length 102: IP 10.1.1.100 > 10.1.1.1: ICMP echo reply,
> .* length 64$" 2>&1 1>/dev/null])
> > +
> > +dnl Second, send the packet that emulates
> > +dnl `ip netns exec at_ns0 ping -s 1600 10.1.1.100`
> > +NS_CHECK_EXEC([at_ns0], [$PYTHON $srcdir/sendpkt.py p0 f2 ff 00 00 00
> 02 f2 ff 00 00 00 03 08 00 45 00 05 ca 9a 7b 40 00 40 2f 3f e6 ac 1f 01 01
> ac 1f 01 64 00 00 65 58 f2 ff 00 00 00 01 f2 ff 00 00 00 04 08 00 45 00 05
> a4 6d 4d 20 00 40 01 d1 a5 0a 01 01 01 0a 01 01 64 08 00 11 cc 13 ed 00 01
> 82 c6 43 5b 00 00 00 00 d2 e1 0c 00 00 00 00 00 $(GEN_ICMP_DATA(16, 1400))
> > /dev/null])
> > +NS_CHECK_EXEC([at_ns0], [$PYTHON $srcdir/sendpkt.py p0 f2 ff 00 00 00
> 02 f2 ff 00 00 00 03 08 00 45 00 00 f2 9a 7c 40 00 40 2f 44 bd ac 1f 01 01
> ac 1f 01 64 00 00 65 58 f2 ff 00 00 00 01 f2 ff 00 00 00 04 08 00 45 00 00
> cc 6d 4d 00 b2 40 01 f5 cb 0a 01 01 01 0a 01 01 64 $(GEN_ICMP_DATA(136,
> 184)) > /dev/null])
> > +
> > +sleep 1
> > +AT_CHECK([tcpdump -xx -r p0.pcap 2>&1 | egrep "IP 172.31.1.100 >
> 172.31.1.1: GREv0, length 222: IP 10.1.1.100 > 10.1.1.1: icmp" 2>&1
> 1>/dev/null])
> > +
> > +dnl Lastly, send the packet that emulates
> > +dnl `ip netns exec at_ns0 ping -s 3200 10.1.1.100`
> > +NS_CHECK_EXEC([at_ns0], [$PYTHON $srcdir/sendpkt.py p0 f2 ff 00 00 00
> 02 f2 ff 00 00 00 03 08 00 45 00 05 ca 9b 5e 40 00 40 2f 3f 03 ac 1f 01 01
> ac 1f 01 64 00 00 65 58 f2 ff 00 00 00 01 f2 ff 00 00 00 04 08 00 45 00 05
> a4 6d af 20 00 40 01 d1 43 0a 01 01 01 0a 01 01 64 08 00 55 ce 13 f4 00 03
> 84 c6 43 5b 00 00 00 00 29 4c 02 00 00 00 00 00 $(GEN_ICMP_DATA(16, 1400))
> > /dev/null])
> > +NS_CHECK_EXEC([at_ns0], [$PYTHON $srcdir/sendpkt.py p0 f2 ff 00 00 00
> 02 f2 ff 00 00 00 03 08 00 45 00 05 ca 9b 5f 40 00 40 2f 3f 02 ac 1f 01 01
> ac 1f 01 64 00 00 65 58 f2 ff 00 00 00 01 f2 ff 00 00 00 04 08 00 45 00 05
> a4 6d af 20 b2 40 01 d0 91 0a 01 01 01 0a 01 01 64 $(GEN_ICMP_DATA(136,
> 1424)) > /dev/null])
> > +NS_CHECK_EXEC([at_ns0], [$PYTHON $srcdir/sendpkt.py p0 f2 ff 00 00 00
> 02 f2 ff 00 00 00 03 08 00 45 00 01 a2 9b 60 40 00 40 2f 43 29 ac 1f 01 01
> ac 1f 01 64 00 00 65 58 f2 ff 00 00 00 01 f2 ff 00 00 00 04 08 00 45 00 01
> 7c 6d af 01 64 40 01 f4 07 0a 01 01 01 0a 01 01 64 $(GEN_ICMP_DATA(24,
> 360)) > /dev/null])
> > +
> > +sleep 1
> > +AT_CHECK([tcpdump -xx -r p0.pcap 2>&1 | egrep "IP 172.31.1.100 >
> 172.31.1.1: GREv0, length 398: IP 10.1.1.100 > 10.1.1.1: icmp" 2>&1
> 1>/dev/null])
>
> My local test fail at the above line. I'm still trying to find out the
> root cause.
>
> Thanks
> William
>