[Qemu-devel] [PATCH v5 06/10] netfilter: add an API to pass the packet to next filter

[Yang Hongyang <yanghy@cn.fujitsu.com>]

add an API qemu_netfilter_pass_to_next() to pass the packet
to next filter.

Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>

---
v5: fold params to NetPacket struct
---
 include/net/filter.h |  3 +++
 net/filter.c         | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/include/net/filter.h b/include/net/filter.h
index f15d83d..9278d40 100644
--- a/include/net/filter.h
+++ b/include/net/filter.h
@@ -57,4 +57,7 @@ void qemu_del_net_filter(NetFilterState *nf);
 void netfilter_add(QemuOpts *opts, Error **errp);
 void qmp_netfilter_add(QDict *qdict, QObject **ret, Error **errp);
 
+/* pass the packet to the next filter */
+ssize_t qemu_netfilter_pass_to_next(NetFilterState *nf, NetPacket *packet);
+
 #endif /* QEMU_NET_FILTER_H */
diff --git a/net/filter.c b/net/filter.c
index dfce544..84245a7 100644
--- a/net/filter.c
+++ b/net/filter.c
@@ -14,9 +14,11 @@
 #include "qapi/dealloc-visitor.h"
 #include "qemu/config-file.h"
 #include "qmp-commands.h"
+#include "qemu/iov.h"
 
 #include "net/filter.h"
 #include "net/net.h"
+#include "net/queue.h"
 
 static QTAILQ_HEAD(, NetFilterState) net_filters;
 
@@ -127,6 +129,37 @@ void qmp_netfilter_del(const char *id, Error **errp)
     qemu_opts_del(opts);
 }
 
+ssize_t qemu_netfilter_pass_to_next(NetFilterState *nf, NetPacket *packet)
+{
+    int ret = 0;
+    NetFilterState *next = QTAILQ_NEXT(nf, next);
+    struct iovec iov = {
+        .iov_base = (void *)packet->data,
+        .iov_len = packet->size
+    };
+
+    while (next) {
+        if (next->chain == nf->chain || next->chain == NET_FILTER_ALL) {
+            ret = next->info->receive_iov(next, packet->sender, packet->flags,
+                                          &iov, 1, packet->sent_cb);
+            if (ret) {
+                return ret;
+            }
+        }
+        next = QTAILQ_NEXT(next, next);
+    }
+
+    /* we have gone through all filters, pass it to receiver */
+    if (packet->sender && packet->sender->peer) {
+        return qemu_net_queue_send_iov(packet->sender->peer->incoming_queue,
+                                       packet->sender, packet->flags,
+                                       &iov, 1, packet->sent_cb);
+    }
+
+    /* no receiver, or sender is deleted, drop this packet, return success */
+    return packet->size;
+}
+
 typedef int (NetFilterInit)(const NetFilterOptions *opts,
                             const char *name, int chain,
                             NetClientState *netdev, Error **errp);
-- 
1.9.1