[Bugme-new] [Bug 16601] New: Multicast MAC when sending via gateway
bugzilla-daemon at bugzilla.kernel.org
bugzilla-daemon at bugzilla.kernel.org
Mon Aug 16 01:06:18 PDT 2010
https://bugzilla.kernel.org/show_bug.cgi?id=16601
Summary: Multicast MAC when sending via gateway
Product: Networking
Version: 2.5
Kernel Version: 2.6.26
Platform: All
OS/Version: Linux
Tree: Mainline
Status: NEW
Severity: normal
Priority: P1
Component: IPV4
AssignedTo: shemminger at linux-foundation.org
ReportedBy: Nikita.Rastegaev at oktetlabs.ru
CC: Alexandra.Kossovsky at oktetlabs.ru
Regression: No
Created an attachment (id=27461)
--> (https://bugzilla.kernel.org/attachment.cgi?id=27461)
Configuration and simple test for the issue
I observe some strange behavior when sending multicast datagrams via gateway.
It appears that destination MAC in UDP packets differs when using connected and
connectionless socket. In case of connectionless socket destination MAC field
of
UDP header is filled with MAC address of gateway, but in case we use connect()
with multicast address, destination MAC is set to multicast MAC. I don't know,
which behavior is right, but different behavior is unexpected.
I run the attached test on thorin1 machine and use thorin2 as a gateway.
thorin1 is running 2.6.26-2-686 kernel, thorin2 is 2.6.26-2-amd64.
I also attach ifconfig and route output for this machines and tcpdump output
on thorin2 when running test. There we can see the following:
16:02:30.567909 00:27:0e:09:01:2a > 00:27:0e:09:02:2a, ethertype IPv4 (0x0800),
length 58: 10.54.10.1.40074 > 237.92.130.210.51721: UDP, length 16
16:02:30.567984 00:27:0e:09:01:2a > 01:00:5e:5c:82:d2, ethertype IPv4 (0x0800),
length 74: 10.54.10.1.43360 > 237.92.130.210.51721: UDP, length 32
--
Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are on the CC list for the bug.
More information about the Bugme-new
mailing list