packet/igmp: Python 3: truncate IGMP timer fields to integers before packing

This patch adds explicit integer conversions to the IGMP timer
fields. This is necessary because Python 3's pack(...) does not
automatically coerce floating-point values to integers (Python 3
actually throws a struct.error on struct.pack('B', 1.0)).

This fixes IgmpQuerier._send_query and IgmpSnooper._do_query under
Python 3, and possibly other functions that pass/assign floats to the
`maxresp' attribute.

Signed-off-by: Fadi Moukayed <smfadi@gmail.com>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

1 files changed, 4 insertions, 3 deletions

diff --git a/ryu/lib/packet/igmp.py b/ryu/lib/packet/igmp.py
index f1d65b0d..cd8f59c7 100644
--- a/ryu/lib/packet/igmp.py
+++ b/ryu/lib/packet/igmp.py
@@ -119,6 +119,7 @@ where each Group Record has the following internal format:
 
 import six
 import struct
+from math import trunc
 
 from ryu.lib import addrconv
 from ryu.lib import stringify
@@ -209,7 +210,7 @@ class igmp(packet_base.PacketBase):
 
     def serialize(self, payload, prev):
         hdr = bytearray(struct.pack(self._PACK_STR, self.msgtype,
-                        self.maxresp, self.csum,
+                        trunc(self.maxresp), self.csum,
                         addrconv.ipv4.text_to_bin(self.address)))
 
         if self.csum == 0:
@@ -299,9 +300,9 @@ class igmpv3_query(igmp):
     def serialize(self, payload, prev):
         s_qrv = self.s_flg << 3 | self.qrv
         buf = bytearray(struct.pack(self._PACK_STR, self.msgtype,
-                        self.maxresp, self.csum,
+                        trunc(self.maxresp), self.csum,
                         addrconv.ipv4.text_to_bin(self.address),
-                        s_qrv, self.qqic, self.num))
+                        s_qrv, trunc(self.qqic), self.num))
         for src in self.srcs:
             buf.extend(struct.pack('4s', addrconv.ipv4.text_to_bin(src)))
         if 0 == self.num: