af_packet: reflect admin device state on host

Setting the interface state in VPP on an af_packet device, was not being
reflected on the host. This implied the user had to set the device state
in VPP and then on the host, in order to put the interface into an 'up'
state. This changes makes the device state consisent in VPP and the host.

Change-Id: I6dc6aee79503e04576683db937b861337a2b375b
Signed-off-by: Ray Kinsella <ray.kinsella@intel.com>
diff --git a/src/vnet/devices/af_packet/af_packet.c b/src/vnet/devices/af_packet/af_packet.c
index 7464d4e..92bd109 100644
--- a/src/vnet/devices/af_packet/af_packet.c
+++ b/src/vnet/devices/af_packet/af_packet.c
@@ -19,6 +19,7 @@
 
 #include <linux/if_ether.h>
 #include <linux/if_packet.h>
+#include <dirent.h>
 
 #include <vlib/vlib.h>
 #include <vlib/unix/unix.h>
@@ -82,26 +83,35 @@
 }
 
 static int
-create_packet_v2_sock (u8 * name, tpacket_req_t * rx_req,
+is_bridge (const u8 * host_if_name)
+{
+  u8 *s;
+  DIR *dir = NULL;
+
+  s = format (0, "/sys/class/net/%s/bridge%c", host_if_name, 0);
+  dir = opendir ((char *) s);
+  vec_free (s);
+
+  if (dir)
+    {
+      closedir (dir);
+      return 0;
+    }
+
+  return -1;
+}
+
+static int
+create_packet_v2_sock (int host_if_index, tpacket_req_t * rx_req,
 		       tpacket_req_t * tx_req, int *fd, u8 ** ring)
 {
   int ret, err;
   struct sockaddr_ll sll;
-  uint host_if_index;
   int ver = TPACKET_V2;
   socklen_t req_sz = sizeof (struct tpacket_req);
   u32 ring_sz = rx_req->tp_block_size * rx_req->tp_block_nr +
     tx_req->tp_block_size * tx_req->tp_block_nr;
 
-  host_if_index = if_nametoindex ((const char *) name);
-
-  if (!host_if_index)
-    {
-      DBG_SOCK ("Wrong host interface name");
-      ret = VNET_API_ERROR_INVALID_INTERFACE;
-      goto error;
-    }
-
   if ((*fd = socket (AF_PACKET, SOCK_RAW, htons (ETH_P_ALL))) < 0)
     {
       DBG_SOCK ("Failed to create socket");
@@ -190,6 +200,7 @@
   uword *p;
   uword if_index;
   u8 *host_if_name_dup = vec_dup (host_if_name);
+  int host_if_index = -1;
 
   p = mhash_get (&apm->if_index_by_host_if_name, host_if_name);
   if (p)
@@ -209,15 +220,29 @@
   tx_req->tp_block_nr = AF_PACKET_TX_BLOCK_NR;
   tx_req->tp_frame_nr = AF_PACKET_TX_FRAME_NR;
 
-  ret = create_packet_v2_sock (host_if_name, rx_req, tx_req, &fd, &ring);
+  host_if_index = if_nametoindex ((const char *) host_if_name);
+
+  if (!host_if_index)
+    {
+      DBG_SOCK ("Wrong host interface name");
+      return VNET_API_ERROR_INVALID_INTERFACE;
+    }
+
+  ret = create_packet_v2_sock (host_if_index, rx_req, tx_req, &fd, &ring);
 
   if (ret != 0)
     goto error;
 
+  ret = is_bridge (host_if_name);
+
+  if (ret == 0)			/* is a bridge, ignore state */
+    host_if_index = -1;
+
   /* So far everything looks good, let's create interface */
   pool_get (apm->interfaces, apif);
   if_index = apif - apm->interfaces;
 
+  apif->host_if_index = host_if_index;
   apif->fd = fd;
   apif->rx_ring = ring;
   apif->tx_ring = ring + rx_req->tp_block_size * rx_req->tp_block_nr;
@@ -341,6 +366,7 @@
 
   vec_free (apif->host_if_name);
   apif->host_if_name = NULL;
+  apif->host_if_index = -1;
 
   mhash_unset (&apm->if_index_by_host_if_name, host_if_name, &if_index);
 
diff --git a/src/vnet/devices/af_packet/af_packet.h b/src/vnet/devices/af_packet/af_packet.h
index 77a2c7a..194977f 100644
--- a/src/vnet/devices/af_packet/af_packet.h
+++ b/src/vnet/devices/af_packet/af_packet.h
@@ -24,6 +24,7 @@
   CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
   clib_spinlock_t lockp;
   u8 *host_if_name;
+  int host_if_index;
   int fd;
   struct tpacket_req *rx_req;
   struct tpacket_req *tx_req;
diff --git a/src/vnet/devices/af_packet/device.c b/src/vnet/devices/af_packet/device.c
index 2ba3f57..2a17e6b 100644
--- a/src/vnet/devices/af_packet/device.c
+++ b/src/vnet/devices/af_packet/device.c
@@ -18,6 +18,8 @@
  */
 
 #include <linux/if_packet.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
 
 #include <vlib/vlib.h>
 #include <vlib/unix/unix.h>
@@ -205,17 +207,51 @@
   af_packet_if_t *apif =
     pool_elt_at_index (apm->interfaces, hw->dev_instance);
   u32 hw_flags;
+  int rv, fd = socket (AF_UNIX, SOCK_DGRAM, 0);
+  struct ifreq ifr;
+
+  /* if interface is a bridge ignore */
+  if (apif->host_if_index < 0)
+    return 0;			/* no error */
+
+  /* use host_if_index in case host name has changed */
+  ifr.ifr_ifindex = apif->host_if_index;
+  if ((rv = ioctl (fd, SIOCGIFNAME, &ifr)) < 0)
+    {
+      clib_unix_warning ("af_packet_%s ioctl could not retrieve eth name",
+			 apif->host_if_name);
+    }
 
   apif->is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0;
 
+  if ((rv = ioctl (fd, SIOCGIFFLAGS, &ifr)) < 0)
+    {
+      clib_unix_warning ("af_packet_%s error: %d",
+			 apif->is_admin_up ? "up" : "down", rv);
+    }
+
   if (apif->is_admin_up)
-    hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP;
+    {
+      hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP;
+      ifr.ifr_flags |= IFF_UP;
+    }
   else
-    hw_flags = 0;
+    {
+      hw_flags = 0;
+      ifr.ifr_flags &= ~IFF_UP;
+    }
+
+  if ((rv = ioctl (fd, SIOCSIFFLAGS, &ifr)) < 0)
+    {
+      clib_unix_warning ("af_packet_%s error: %d",
+			 apif->is_admin_up ? "up" : "down", rv);
+    }
 
   vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);
 
-  return 0;
+  close (fd);
+
+  return 0;			/* no error */
 }
 
 static clib_error_t *