On 01/28/2016 01:44 PM, Jason Wang wrote:
On 01/27/2016 10:40 AM, Zhang Chen wrote:
From: ZhangChen <zhangchen.f...@cn.fujitsu.com>
Traffic-mirror is a netfilter plugin.
It gives qemu the ability to copy and mirror guest's
net packet. we output packet to chardev.
usage:
-netdev tap,id=hn0
-chardev socket,id=mirror0,host=ip_primary,port=X,server,nowait
-traffic-mirror,id=m0,netdev=hn0,queue=tx/rx/all,outdev=mirror0
Signed-off-by: ZhangChen <zhangchen.f...@cn.fujitsu.com>
Signed-off-by: Wen Congyang <we...@cn.fujitsu.com>
Reviewed-by: Yang Hongyang <hongyang.y...@easystack.cn>
Thanks for the patch. Several questions:
- I'm curious about how the patch was tested? Simple setup e.g:
-netdev tap,id=hn0 -device virtio-net-pci,netdev=hn0 -chardev
socket,id=c0,host=localhost,port=4444,server,nowait -object
traffic-mirror,netdev=hn0,outdev=c0,id=f0 -netdev
socket,id=s0,connect=127.0.0.1:4444 -device e1000,netdev=s0
does not works for me.
I test it in this way.
primary:
-netdev tap,id=hn0 -device e1000,netdev=hn0 -chardev
socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
-object traffic-mirror,id=f0,netdev=hn0,queue=tx,outdev=mirror0
secondary:
-netdev tap,id=hn0 -device e1000,netdev=hn0 -chardev
socket,id=mirror0,host=3.3.3.3,port=9003 -object
traffic-reader,id=f1,netdev=hn0,queue=rx,indev=mirror0
I write a traffic-reader demo to read chardev socket and print it in
monitor.
- Is a reliable mirroring (e.g no packet drops during mirroring) is
needed for COLO? If yes, this patch seems could not guarantee this.
I will fix it in V3
- Please consider to write a unit test for this patch.
write a unit test like tests/test-netfilter.c ?
And see comments below.
Thanks
---
net/Makefile.objs | 1 +
net/traffic-mirror.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++++++
qemu-options.hx | 5 ++
vl.c | 3 +-
4 files changed, 181 insertions(+), 1 deletion(-)
create mode 100644 net/traffic-mirror.c
diff --git a/net/Makefile.objs b/net/Makefile.objs
index 5fa2f97..de06ebe 100644
--- a/net/Makefile.objs
+++ b/net/Makefile.objs
@@ -15,3 +15,4 @@ common-obj-$(CONFIG_VDE) += vde.o
common-obj-$(CONFIG_NETMAP) += netmap.o
common-obj-y += filter.o
common-obj-y += filter-buffer.o
+common-obj-y += traffic-mirror.o
Let's s/traffic-mirror/filter-mirror/g to be consistent with other filters.
OK~ I will fix it in V3
diff --git a/net/traffic-mirror.c b/net/traffic-mirror.c
new file mode 100644
index 0000000..bed915c
--- /dev/null
+++ b/net/traffic-mirror.c
@@ -0,0 +1,173 @@
+/*
+ * Copyright (c) 2016 HUAWEI TECHNOLOGIES CO., LTD.
+ * Copyright (c) 2016 FUJITSU LIMITED
+ * Copyright (c) 2016 Intel Corporation
+ *
+ * Author: Zhang Chen <zhangchen.f...@cn.fujitsu.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later. See the COPYING file in the top-level directory.
+ */
+
+#include "net/filter.h"
+#include "net/net.h"
+#include "qemu-common.h"
+#include "qapi/qmp/qerror.h"
+#include "qapi-visit.h"
+#include "qom/object.h"
+#include "qemu/main-loop.h"
+#include "qemu/error-report.h"
+#include "trace.h"
+#include "sysemu/char.h"
+#include "qemu/iov.h"
+
+#define FILTER_TRAFFIC_MIRROR(obj) \
+ OBJECT_CHECK(MirrorState, (obj), TYPE_FILTER_TRAFFIC_MIRROR)
+
+#define TYPE_FILTER_TRAFFIC_MIRROR "traffic-mirror"
+
+typedef struct MirrorState {
+ NetFilterState parent_obj;
+ char *outdev;
+ CharDriverState *chr_out;
+
+} MirrorState;
+
+static ssize_t traffic_mirror_send(NetFilterState *nf,
+ const struct iovec *iov,
+ int iovcnt)
+{
+ MirrorState *s = FILTER_TRAFFIC_MIRROR(nf);
+ ssize_t ret = 0;
+ ssize_t size = 0;
+ char *buf;
+
+ size = iov_size(iov, iovcnt);
+ if (!size) {
+ return 0;
+ }
+
+ buf = g_malloc0(size);
+ iov_to_buf(iov, iovcnt, 0, buf, size);
+ ret = qemu_chr_fe_write(s->chr_out, (uint8_t *)&size, sizeof(size));
htonl(size)?
We do not need this.
+ if (ret < 0) {
This check is not sufficient, for some reason, only part of the packets
maybe sent by the socket. Need to handle this properly, otherwise it may
confuse receiver.
I will fix it in next version.
+ g_free(buf);
+ return ret;
+ }
+
+ ret = qemu_chr_fe_write(s->chr_out, (uint8_t *)buf, size);
+ g_free(buf);
+ return ret;
Ditto.
I will fix it in next version.
+}
+
+static ssize_t traffic_mirror_receive_iov(NetFilterState *nf,
+ NetClientState *sender,
+ unsigned flags,
+ const struct iovec *iov,
+ int iovcnt,
+ NetPacketSent *sent_cb)
+{
+ /*
+ * We copy and mirror packet to outdev,
+ * then put back the packet.
+ */
The code could explain itself, so the comment is unnecessary.
OK,I will remove it.
Thanks
zhangchen
+ ssize_t ret = 0;
+
+ ret = traffic_mirror_send(nf, iov, iovcnt);
+ if (ret < 0) {
+ error_report("traffic_mirror_send failed");
Monitor could be flooded by this.
+ }
+
+ return 0;
+}
+
Other looks good.
.
--
Thanks
zhangchen
