Re: [Qemu-devel] [PATCH] net/traffic-mirrorer:Add traffic-mirroer

[Zhang Chen <zhangchen.fnst@cn.fujitsu.com>]

On 01/27/2016 03:46 AM, Dr. David Alan Gilbert wrote:
> * Yang Hongyang (hongyang.yang@easystack.cn) wrote:
>>
>> On 01/26/2016 04:59 PM, Zhang Chen wrote:
>>> From: ZhangChen <zhangchen.fnst@cn.fujitsu.com>
>>>
>>> Traffic-mirrorer is a plugin of netfilter.
>> netfilter plugin

fix

>>> It make qemu has ability to copy and mirror guest's
>> s/make/makes/    has the ability
> Not quite.
>    'It gives qemu the ability to...'
>
> (Sorry, I can't explain why!).

I will fix it in next version.

>>> net packet. we output packet to chardev.
>> there seems no 'mirrorer' in english, I think the plugin name
>> 'traffic-mirror' is enough.
> Agreed.

I will fix it in next version.
Thanks for review~~
zhangchen

> Dave
>
>>> usage:
>>>
>>> -netdev tap,id=hn0
>>> -chardev socket,id=mirrorer0,host=ip_primary,port=X,server,nowait
>>> -traffic-mirrorer,id=m0,netdev=hn0,queue=tx,outdev=mirrorer0
>>>
>>> Signed-off-by: ZhangChen <zhangchen.fnst@cn.fujitsu.com>
>>> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
>> The code looks good overall, so:
>> Reviewed-by: Yang Hongyang <hongyang.yang@easystack.cn>

Thank you Yang~~~

>>> ---
>>>   net/Makefile.objs      |   1 +
>>>   net/traffic-mirrorer.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++++
>>>   qemu-options.hx        |   5 ++
>>>   vl.c                   |   3 +-
>>>   4 files changed, 181 insertions(+), 1 deletion(-)
>>>   create mode 100644 net/traffic-mirrorer.c
>>>
>>> diff --git a/net/Makefile.objs b/net/Makefile.objs
>>> index 5fa2f97..6466764 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-mirrorer.o
>>> diff --git a/net/traffic-mirrorer.c b/net/traffic-mirrorer.c
>>> new file mode 100644
>>> index 0000000..3b0da82
>>> --- /dev/null
>>> +++ b/net/traffic-mirrorer.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.fnst@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_MIRRORER(obj) \
>>> +    OBJECT_CHECK(MirrorerState, (obj), TYPE_FILTER_TRAFFIC_MIRRORER)
>>> +
>>> +#define TYPE_FILTER_TRAFFIC_MIRRORER "traffic-mirrorer"
>>> +
>>> +typedef struct MirrorerState {
>>> +    NetFilterState parent_obj;
>>> +    char *outdev;
>>> +    CharDriverState *chr_out;
>>> +
>>> +} MirrorerState;
>>> +
>>> +static ssize_t traffic_mirrorer_send(NetFilterState *nf,
>>> +                                         const struct iovec *iov,
>>> +                                         int iovcnt)
>>> +{
>>> +    MirrorerState *s = FILTER_TRAFFIC_MIRRORER(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));
>>> +    if (ret < 0) {
>>> +        g_free(buf);
>>> +        return ret;
>>> +    }
>>> +
>>> +    ret = qemu_chr_fe_write(s->chr_out, (uint8_t *)buf, size);
>>> +    g_free(buf);
>>> +    return ret;
>>> +}
>>> +
>>> +static ssize_t traffic_mirrorer_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.
>>> +     */
>>> +    ssize_t ret = 0;
>>> +
>>> +    ret = traffic_mirrorer_send(nf, iov, iovcnt);
>>> +    if (ret < 0) {
>>> +        error_report("traffic_mirrorer_send failed");
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static void traffic_mirrorer_cleanup(NetFilterState *nf)
>>> +{
>>> +    MirrorerState *s = FILTER_TRAFFIC_MIRRORER(nf);
>>> +
>>> +    if (s->chr_out) {
>>> +        qemu_chr_fe_release(s->chr_out);
>>> +    }
>>> +}
>>> +
>>> +static void traffic_mirrorer_setup(NetFilterState *nf, Error **errp)
>>> +{
>>> +    MirrorerState *s = FILTER_TRAFFIC_MIRRORER(nf);
>>> +
>>> +    if (!s->outdev) {
>>> +        error_setg(errp, "filter traffic mirrorer needs 'outdev' property set!"
>>> +                "property set!");
>>> +        return;
>>> +    }
>>> +
>>> +    s->chr_out = qemu_chr_find(s->outdev);
>>> +    if (s->chr_out == NULL) {
>>> +        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
>>> +                  "Device '%s' not found", s->outdev);
>>> +        return;
>>> +    }
>>> +
>>> +    if (qemu_chr_fe_claim(s->chr_out) != 0) {
>>> +        error_setg(errp, QERR_DEVICE_IN_USE, s->outdev);
>>> +        return;
>>> +    }
>>> +}
>>> +
>>> +static void traffic_mirrorer_class_init(ObjectClass *oc, void *data)
>>> +{
>>> +    NetFilterClass *nfc = NETFILTER_CLASS(oc);
>>> +
>>> +    nfc->setup = traffic_mirrorer_setup;
>>> +    nfc->cleanup = traffic_mirrorer_cleanup;
>>> +    nfc->receive_iov = traffic_mirrorer_receive_iov;
>>> +}
>>> +
>>> +static char *traffic_mirrorer_get_outdev(Object *obj, Error **errp)
>>> +{
>>> +    MirrorerState *s = FILTER_TRAFFIC_MIRRORER(obj);
>>> +
>>> +    return g_strdup(s->outdev);
>>> +}
>>> +
>>> +static void
>>> +traffic_mirrorer_set_outdev(Object *obj, const char *value, Error **errp)
>>> +{
>>> +    MirrorerState *s = FILTER_TRAFFIC_MIRRORER(obj);
>>> +
>>> +    g_free(s->outdev);
>>> +    s->outdev = g_strdup(value);
>>> +    if (!s->outdev) {
>>> +        error_setg(errp, "filter traffic mirrorer needs 'outdev' "
>>> +                "property set!");
>>> +        return;
>>> +    }
>>> +}
>>> +
>>> +static void traffic_mirrorer_init(Object *obj)
>>> +{
>>> +    object_property_add_str(obj, "outdev", traffic_mirrorer_get_outdev,
>>> +                            traffic_mirrorer_set_outdev, NULL);
>>> +}
>>> +
>>> +static void traffic_mirrorer_fini(Object *obj)
>>> +{
>>> +    MirrorerState *s = FILTER_TRAFFIC_MIRRORER(obj);
>>> +
>>> +    g_free(s->outdev);
>>> +}
>>> +
>>> +static const TypeInfo traffic_mirrorer_info = {
>>> +    .name = TYPE_FILTER_TRAFFIC_MIRRORER,
>>> +    .parent = TYPE_NETFILTER,
>>> +    .class_init = traffic_mirrorer_class_init,
>>> +    .instance_init = traffic_mirrorer_init,
>>> +    .instance_finalize = traffic_mirrorer_fini,
>>> +    .instance_size = sizeof(MirrorerState),
>>> +};
>>> +
>>> +static void register_types(void)
>>> +{
>>> +    type_register_static(&traffic_mirrorer_info);
>>> +}
>>> +
>>> +type_init(register_types);
>>> diff --git a/qemu-options.hx b/qemu-options.hx
>>> index 0eea4ee..ecfa297 100644
>>> --- a/qemu-options.hx
>>> +++ b/qemu-options.hx
>>> @@ -3670,6 +3670,11 @@ queue @var{all|rx|tx} is an option that can be applied to any netfilter.
>>>   @option{tx}: the filter is attached to the transmit queue of the netdev,
>>>                where it will receive packets sent by the netdev.
>>>
>>> +@item -object traffic-mirrorer,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
>>> +
>>> +traffic-mirrorer on netdev @var{netdevid},mirror net packet to outdev.
>>> +queue @var{all|rx|tx} is an option that can be applied to traffic-mirrorer.
>>> +
>>>   @item -object filter-dump,id=@var{id},netdev=@var{dev},file=@var{filename}][,maxlen=@var{len}]
>>>
>>>   Dump the network traffic on netdev @var{dev} to the file specified by
>>> diff --git a/vl.c b/vl.c
>>> index 8dc34ce..4fe01bc 100644
>>> --- a/vl.c
>>> +++ b/vl.c
>>> @@ -2838,7 +2838,8 @@ static bool object_create_initial(const char *type)
>>>        * they depend on netdevs already existing
>>>        */
>>>       if (g_str_equal(type, "filter-buffer") ||
>>> -        g_str_equal(type, "filter-dump")) {
>>> +        g_str_equal(type, "filter-dump") ||
>>> +        g_str_equal(type, "traffic-mirrorer")) {
>>>           return false;
>>>       }
>>>
>>>
>> -- 
>> Thanks,
>> Yang
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>
>
> .
>

-- 
Thanks
zhangchen