[ovs-dev] [PATCH 3/3] tests: Ignore options order in dhcpv4 ovn test.

[Daniele Di Proietto]

The order of the options in the packet generated by ovs-controller
depends on the hash function.  I believe that murmur hash (our default)
produces different outputs depending on the endianness of the system.

This commit fixes the test by reordering the options in the packet
before checking them.

This was reported before as a failure of the test on x86 with sse42
enabled, I'm fixing it now because it affects other targets build by
distros by default.

Reported-at: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=840770
Signed-off-by: Daniele Di Proietto <diproiettod at vmware.com>
---
 tests/ovn.at | 46 ++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 42 insertions(+), 4 deletions(-)

diff --git a/tests/ovn.at b/tests/ovn.at
index cb21210..20f0135 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -3751,6 +3751,34 @@ echo "---------------------"
 echo "------ hv1 dump ----------"
 as hv1 ovs-ofctl dump-flows br-int
 
+sort_dhcpv4opts_tlv() {
+    awk '
+    function parsehex(h,    r,i,d) {
+        r = 0;
+        for (i = 1; i <= length(h); i++) {
+            d = index("0123456789abcdef", substr(h,i,1));
+            if (d == 0) {
+                break;
+            }
+            r = r * 16 + (d - 1);
+        }
+        return r;
+    }
+
+    {
+        opts = $0
+        while (length(opts) >= 4) {
+            type = substr(opts, 1, 2);
+            s_len = substr(opts, 3, 2);
+            len = parsehex(s_len)
+            value = substr(opts, 5, len * 2);
+            opts = substr(opts, 5 + len * 2);
+            print type s_len value;
+        }
+        print opts
+    }' | sort | tr -d "\n\r"
+}
+
 # Send DHCPDISCOVER.
 offer_ip=`ip_to_hex 10 0 0 4`
 server_ip=`ip_to_hex 10 0 0 1`
@@ -3764,8 +3792,13 @@ $PYTHON "$top_srcdir/utilities/ovs-pcap.in" hv1/vif1-tx.pcap > 1.packets
 cat 1.expected | cut -c -48 > expout
 AT_CHECK([cat 1.packets | cut -c -48], [0], [expout])
 # Skipping the IPv4 checksum.
-cat 1.expected | cut -c 53- > expout
-AT_CHECK([cat 1.packets | cut -c 53-], [0], [expout])
+cat 1.expected | cut -c 53-570 > expout
+AT_CHECK([cat 1.packets | cut -c 53-570], [0], [expout])
+# The ordering of the options in the packet depends on the hash function used
+# and possibly on the endianness of the system.  We parse and sort both the
+# expected and the generated packet.
+cat 1.expected | cut -c 571 | sort_dhcpv4opts_tlv > expout
+AT_CHECK([cat 1.packets | cut -c 571 | sort_dhcpv4opts_tlv], [0], [expout])
 
 # ovs-ofctl also resumes the packets and this causes other ports to receive
 # the DHCP request packet. So reset the pcap files so that its easier to test.
@@ -3787,8 +3820,13 @@ $PYTHON "$top_srcdir/utilities/ovs-pcap.in" hv1/vif2-tx.pcap > 2.packets
 cat 2.expected | cut -c -48 > expout
 AT_CHECK([cat 2.packets | cut -c -48], [0], [expout])
 # Skipping the IPv4 checksum.
-cat 2.expected | cut -c 53- > expout
-AT_CHECK([cat 2.packets | cut -c 53-], [0], [expout])
+cat 2.expected | cut -c 53-570 > expout
+AT_CHECK([cat 2.packets | cut -c 53-570], [0], [expout])
+# The ordering of the options in the packet depends on the hash function used
+# and possibly on the endianness of the system.  We parse and sort both the
+# expected and the generated packet.
+cat 2.expected | cut -c 571 | sort_dhcpv4opts_tlv > expout
+AT_CHECK([cat 2.packets | cut -c 571 | sort_dhcpv4opts_tlv], [0], [expout])
 
 reset_pcap_file hv1-vif1 hv1/vif1
 reset_pcap_file hv1-vif2 hv1/vif2
-- 
2.10.2