Re: [Qemu-devel] [PATCH V5 1/2] net/filter-mirror:Add filter-mirror

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

On 02/24/2016 11:22 AM, Jason Wang wrote:
>
> On 02/23/2016 08:00 PM, Zhang Chen wrote:
>> Filter-mirror is a netfilter plugin.
>> It gives qemu the ability to mirror
>> packets to a chardev.
>>
>> usage:
>>
>> -netdev tap,id=hn0
>> -chardev socket,id=mirror0,host=ip_primary,port=X,server,nowait
>> -filter-mirror,id=m0,netdev=hn0,queue=tx/rx/all,outdev=mirror0
>>
>> Signed-off-by: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
>> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
>> Reviewed-by: Yang Hongyang <hongyang.yang@easystack.cn>
>> Reviewed-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
>> ---
>>   net/Makefile.objs   |   1 +
>>   net/filter-mirror.c | 181 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>>   qemu-options.hx     |   5 ++
>>   vl.c                |   3 +-
>>   4 files changed, 189 insertions(+), 1 deletion(-)
>>   create mode 100644 net/filter-mirror.c
>>
>> diff --git a/net/Makefile.objs b/net/Makefile.objs
>> index 5fa2f97..b7c22fd 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 += filter-mirror.o
>> diff --git a/net/filter-mirror.c b/net/filter-mirror.c
>> new file mode 100644
>> index 0000000..ad722f7
>> --- /dev/null
>> +++ b/net/filter-mirror.c
>> @@ -0,0 +1,181 @@
>> +/*
>> + * 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"
>> +#include "qemu/sockets.h"
>> +
>> +#define FILTER_MIRROR(obj) \
>> +    OBJECT_CHECK(MirrorState, (obj), TYPE_FILTER_MIRROR)
>> +
>> +#define TYPE_FILTER_MIRROR "filter-mirror"
>> +
>> +typedef struct MirrorState {
>> +    NetFilterState parent_obj;
>> +    char *outdev;
>> +    CharDriverState *chr_out;
>> +} MirrorState;
>> +
>> +static int filter_mirror_send(NetFilterState *nf,
>> +                                   const struct iovec *iov,
>> +                                   int iovcnt)
>> +{
>> +    MirrorState *s = FILTER_MIRROR(nf);
>> +    int ret = 0;
>> +    ssize_t size = 0;
>> +    uint32_t len =  0;
>> +    char *buf;
>> +
>> +    size = iov_size(iov, iovcnt);
>> +    if (!size) {
>> +        return 0;
>> +    }
>> +
>> +    len = htonl(size);
>> +    ret = qemu_chr_fe_write_all(s->chr_out, (uint8_t *)&len, sizeof(len));
>> +    if (ret != sizeof(len)) {
>> +        goto err;
>> +    }
>> +
>> +    buf = g_malloc(size);
>> +    iov_to_buf(iov, iovcnt, 0, buf, size);
>> +    ret = qemu_chr_fe_write_all(s->chr_out, (uint8_t *)buf, size);
>> +    g_free(buf);
>> +    if (ret != size) {
>> +        goto err;
>> +    }
>> +
>> +    return 0;
>> +
>> +err:
>> +      return ret < 0 ? ret : -EIO;
> The indentation looks odd here.
>
> Other looks good.

Thanks~~ fix it in next version~

zhangchen

>> +}
>> +
>> +static ssize_t filter_mirror_receive_iov(NetFilterState *nf,
>> +                                         NetClientState *sender,
>> +                                         unsigned flags,
>> +                                         const struct iovec *iov,
>> +                                         int iovcnt,
>> +                                         NetPacketSent *sent_cb)
>> +{
>> +    int ret;
>> +
>> +    ret = filter_mirror_send(nf, iov, iovcnt);
>> +    if (ret) {
>> +        error_report("filter_mirror_send failed(%s)", strerror(-ret));
>> +    }
>> +
>> +    /*
>> +     * we don't hope this error interrupt the normal
>> +     * path of net packet, so we always return zero.
>> +     */
>> +    return 0;
>> +}
>> +
>> +static void filter_mirror_cleanup(NetFilterState *nf)
>> +{
>> +    MirrorState *s = FILTER_MIRROR(nf);
>> +
>> +    if (s->chr_out) {
>> +        qemu_chr_fe_release(s->chr_out);
>> +    }
>> +}
>> +
>> +static void filter_mirror_setup(NetFilterState *nf, Error **errp)
>> +{
>> +    MirrorState *s = FILTER_MIRROR(nf);
>> +
>> +    if (!s->outdev) {
>> +        error_setg(errp, "filter filter mirror needs 'outdev' "
>> +                "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 filter_mirror_class_init(ObjectClass *oc, void *data)
>> +{
>> +    NetFilterClass *nfc = NETFILTER_CLASS(oc);
>> +
>> +    nfc->setup = filter_mirror_setup;
>> +    nfc->cleanup = filter_mirror_cleanup;
>> +    nfc->receive_iov = filter_mirror_receive_iov;
>> +}
>> +
>> +static char *filter_mirror_get_outdev(Object *obj, Error **errp)
>> +{
>> +    MirrorState *s = FILTER_MIRROR(obj);
>> +
>> +    return g_strdup(s->outdev);
>> +}
>> +
>> +static void
>> +filter_mirror_set_outdev(Object *obj, const char *value, Error **errp)
>> +{
>> +    MirrorState *s = FILTER_MIRROR(obj);
>> +
>> +    g_free(s->outdev);
>> +    s->outdev = g_strdup(value);
>> +    if (!s->outdev) {
>> +        error_setg(errp, "filter filter mirror needs 'outdev' "
>> +                "property set");
>> +        return;
>> +    }
>> +}
>> +
>> +static void filter_mirror_init(Object *obj)
>> +{
>> +    object_property_add_str(obj, "outdev", filter_mirror_get_outdev,
>> +                            filter_mirror_set_outdev, NULL);
>> +}
>> +
>> +static void filter_mirror_fini(Object *obj)
>> +{
>> +    MirrorState *s = FILTER_MIRROR(obj);
>> +
>> +    g_free(s->outdev);
>> +}
>> +
>> +static const TypeInfo filter_mirror_info = {
>> +    .name = TYPE_FILTER_MIRROR,
>> +    .parent = TYPE_NETFILTER,
>> +    .class_init = filter_mirror_class_init,
>> +    .instance_init = filter_mirror_init,
>> +    .instance_finalize = filter_mirror_fini,
>> +    .instance_size = sizeof(MirrorState),
>> +};
>> +
>> +static void register_types(void)
>> +{
>> +    type_register_static(&filter_mirror_info);
>> +}
>> +
>> +type_init(register_types);
>> diff --git a/qemu-options.hx b/qemu-options.hx
>> index 2f0465e..ca27863 100644
>> --- a/qemu-options.hx
>> +++ b/qemu-options.hx
>> @@ -3759,6 +3759,11 @@ 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 filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
>> +
>> +filter-mirror on netdev @var{netdevid},mirror net packet to chardev
>> +@var{chardevid}
>> +
>>   @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 175ebcc..d68533a 100644
>> --- a/vl.c
>> +++ b/vl.c
>> @@ -2798,7 +2798,8 @@ 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, "filter-mirror")) {
>>           return false;
>>       }
>>   
>
>
> .
>

-- 
Thanks
zhangchen