Add qemu_send_raw() to vlan.

[Gleb Natapov <gleb@redhat.com>]

It gets packet without virtio header and adds it if needed.  Allows to
inject packets to vlan from outside. To send gracious arp for instance.

diff --git a/hw/virtio-net.c b/hw/virtio-net.c
index 8e9178d..3c77b99 100644
--- a/hw/virtio-net.c
+++ b/hw/virtio-net.c
@@ -389,7 +389,7 @@ static int iov_fill(struct iovec *iov, int iovcnt, const void *buf, int count)
 }
 
 static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt,
-                          const void *buf, size_t size, size_t hdr_len)
+                          const void *buf, size_t size, size_t hdr_len, int raw)
 {
     struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)iov[0].iov_base;
     int offset = 0;
@@ -399,7 +399,11 @@ static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt,
 
 #ifdef TAP_VNET_HDR
     if (tap_has_vnet_hdr(n->vc->vlan->first_client)) {
-        memcpy(hdr, buf, sizeof(*hdr));
+        if (!raw) {
+            memcpy(hdr, buf, sizeof(*hdr));
+        } else {
+            memset(hdr, 0, sizeof(*hdr));
+        }
         offset = sizeof(*hdr);
         work_around_broken_dhclient(hdr, buf + offset, size - offset);
     }
@@ -452,7 +456,7 @@ static int receive_filter(VirtIONet *n, const uint8_t *buf, int size)
     return 0;
 }
 
-static void virtio_net_receive(void *opaque, const uint8_t *buf, int size)
+static void virtio_net_receive2(void *opaque, const uint8_t *buf, int size, int raw)
 {
     VirtIONet *n = opaque;
     struct virtio_net_hdr_mrg_rxbuf *mhdr = NULL;
@@ -502,7 +506,7 @@ static void virtio_net_receive(void *opaque, const uint8_t *buf, int size)
                 mhdr = (struct virtio_net_hdr_mrg_rxbuf *)sg[0].iov_base;
 
             offset += receive_header(n, sg, elem.in_num,
-                                     buf + offset, size - offset, hdr_len);
+                                     buf + offset, size - offset, hdr_len, raw);
             total += hdr_len;
         }
 
@@ -524,6 +528,16 @@ static void virtio_net_receive(void *opaque, const uint8_t *buf, int size)
     virtio_notify(&n->vdev, n->rx_vq);
 }
 
+static void virtio_net_receive(void *opaque, const uint8_t *buf, int size)
+{
+    virtio_net_receive2(opaque, buf, size, 0);
+}
+
+static void virtio_net_receive_raw(void *opaque, const uint8_t *buf, int size)
+{
+    virtio_net_receive2(opaque, buf, size, 1);
+}
+
 /* TX */
 static void virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
 {
@@ -721,6 +735,7 @@ VirtIODevice *virtio_net_init(DeviceState *dev)
                                  virtio_net_can_receive,
                                  virtio_net_cleanup, n);
     n->vc->link_status_changed = virtio_net_set_link_status;
+    n->vc->fd_read_raw = virtio_net_receive_raw;
 
     qemu_format_nic_info_str(n->vc, n->mac);
 
diff --git a/net.c b/net.c
index 3dfc728..01e31db 100644
--- a/net.c
+++ b/net.c
@@ -456,6 +456,31 @@ int qemu_send_packet(VLANClientState *vc, const uint8_t *buf, int size)
     return ret;
 }
 
+void qemu_send_packet_raw(VLANClientState *sender, const uint8_t *buf, int size)
+{
+    VLANState *vlan = sender->vlan;
+    VLANClientState *vc;
+
+    if (sender->link_down)
+        return;
+
+#ifdef DEBUG_NET
+    printf("vlan %d send raw:\n", vlan->id);
+    hex_dump(stdout, buf, size);
+#endif
+    for(vc = vlan->first_client; vc != NULL; vc = vc->next) {
+        if (vc == sender || vc->link_down) {
+            continue;
+        }
+        if (vc->fd_read_raw) {
+            vc->fd_read_raw(vc->opaque, buf, size);
+        } else {
+            vc->fd_read(vc->opaque, buf, size);
+        }
+    }
+    return;
+}
+
 static ssize_t vc_sendv_compat(VLANClientState *vc, const struct iovec *iov,
                                int iovcnt)
 {
@@ -823,6 +848,29 @@ static void tap_receive(void *opaque, const uint8_t *buf, int size)
     tap_receive_iov(opaque, iov, i);
 }
 
+static void tap_receive_raw(void *opaque, const uint8_t *buf, int size)
+{
+    struct iovec iov[2];
+    int i = 0;
+
+#ifdef IFF_VNET_HDR
+    TAPState *s = opaque;
+    struct virtio_net_hdr hdr = { 0, };
+
+    if (s->has_vnet_hdr && s->using_vnet_hdr) {
+        iov[i].iov_base = &hdr;
+        iov[i].iov_len  = sizeof(hdr);
+        i++;
+    }
+#endif
+
+    iov[i].iov_base = (char *) buf;
+    iov[i].iov_len  = size;
+    i++;
+
+    tap_receive_iov(opaque, iov, i);
+}
+
 static int tap_can_send(void *opaque)
 {
     TAPState *s = opaque;
@@ -992,6 +1040,7 @@ static TAPState *net_tap_fd_init(VLANState *vlan,
     s->vc = qemu_new_vlan_client(vlan, model, name, tap_receive,
                                  NULL, tap_cleanup, s);
     s->vc->fd_readv = tap_receive_iov;
+    s->vc->fd_read_raw = tap_receive_raw;
 #ifdef TUNSETOFFLOAD
     s->vc->set_offload = tap_set_offload;
     tap_set_offload(s->vc, 0, 0, 0, 0);
diff --git a/net.h b/net.h
index 931133b..3d0b6f2 100644
--- a/net.h
+++ b/net.h
@@ -15,6 +15,7 @@ typedef void (SetOffload)(VLANClientState *, int, int, int, int);
 
 struct VLANClientState {
     IOReadHandler *fd_read;
+    IOReadHandler *fd_read_raw;
     IOReadvHandler *fd_readv;
     /* Packets may still be sent if this returns zero.  It's used to
        rate-limit the slirp code.  */
@@ -63,6 +64,7 @@ int qemu_can_send_packet(VLANClientState *vc);
 ssize_t qemu_sendv_packet(VLANClientState *vc, const struct iovec *iov,
                           int iovcnt);
 int qemu_send_packet(VLANClientState *vc, const uint8_t *buf, int size);
+void qemu_send_packet_raw(VLANClientState *vc, const uint8_t *buf, int size);
 void qemu_format_nic_info_str(VLANClientState *vc, uint8_t macaddr[6]);
 void qemu_check_nic_model(NICInfo *nd, const char *model);
 void qemu_check_nic_model_list(NICInfo *nd, const char * const *models,
--
			Gleb.