net: Add support for capturing VLANs (Jan Kiszka)
This patch is derived from Tristan Gingold's patch. It adds a new VLAN
client type that writes all traffic on the VLAN it is attached to into a
pcap file. Such a file can then be analyzed offline with Wireshark or
tcpdump.
Besides rebasing and some minor cleanups, the major differences to the
original version are:
- support for enabling/disabling via the monitor (host_net_add/remove)
- no special ordering of VLAN client list, qemu_send_packet now takes
care of properly ordered packets
- 64k default capturing limit (I hate tcpdump's default)
Signed-off-by: Jan Kiszka <[email protected]>
Signed-off-by: Anthony Liguori <[email protected]>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7200 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/qemu-options.hx b/qemu-options.hx
index 1d783e5..718b10a 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -745,6 +745,8 @@
" Use group 'groupname' and mode 'octalmode' to change default\n"
" ownership and permissions for communication port.\n"
#endif
+ "-net dump[,vlan=n][,file=f][,len=n]\n"
+ " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
"-net none use it alone to have zero network devices; if no -net option\n"
" is provided, the default is '-net nic -net user'\n")
STEXI
@@ -865,6 +867,11 @@
qemu linux.img -net nic -net vde,sock=/tmp/myswitch
@end example
+@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
+Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
+At most @var{len} bytes (64k by default) per packet are stored. The file format is
+libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
+
@item -net none
Indicate that no network devices should be configured. It is used to
override the default configuration (@option{-net nic -net user}) which
