ethernet: mac must support 64-bits loads

ethernet dataplane loads MAC addresses as 64-bits loads for efficiency.
We must make sure it is valid, especially for the vector of secondary
MACs.

Type: fix

Change-Id: I851e319b8a973c154e85ff9f05f3b8e385939788
Signed-off-by: Benoît Ganne <bganne@cisco.com>

3 files changed, 67 insertions, 40 deletions

diff --git a/src/vnet/ethernet/ethernet.h b/src/vnet/ethernet/ethernet.h
index afb932931b7..a83b0f39295 100644
--- a/src/vnet/ethernet/ethernet.h
+++ b/src/vnet/ethernet/ethernet.h
@@ -132,6 +132,17 @@ typedef u32 (ethernet_flag_change_function_t)
 #define ETHERNET_MIN_PACKET_BYTES  64
 #define ETHERNET_MAX_PACKET_BYTES  9216
 
+/* ethernet dataplane loads mac address as u64 for efficiency */
+typedef union ethernet_interface_address
+{
+  struct
+  {
+    mac_address_t mac;
+    u16 zero;
+  };
+  u64 as_u64;
+} ethernet_interface_address_t;
+
 /* Ethernet interface instance. */
 typedef struct ethernet_interface
 {
@@ -160,10 +171,10 @@ typedef struct ethernet_interface
   u32 driver_instance;
 
   /* Ethernet (MAC) address for this interface. */
-  u8 address[6];
+  ethernet_interface_address_t address;
 
   /* Secondary MAC addresses for this interface */
-  mac_address_t *secondary_addrs;
+  ethernet_interface_address_t *secondary_addrs;
 } ethernet_interface_t;
 
 extern vnet_hw_interface_class_t ethernet_hw_interface_class;
diff --git a/src/vnet/ethernet/interface.c b/src/vnet/ethernet/interface.c
index b09e2b02256..b5c48193bf3 100644
--- a/src/vnet/ethernet/interface.c
+++ b/src/vnet/ethernet/interface.c
@@ -144,7 +144,7 @@ ethernet_build_rewrite (vnet_main_t * vnm,
   vec_validate (rewrite, n_bytes - 1);
   h = (ethernet_header_t *) rewrite;
   ei = pool_elt_at_index (em->interfaces, hw->hw_instance);
-  clib_memcpy (h->src_address, ei->address, sizeof (h->src_address));
+  clib_memcpy (h->src_address, &ei->address, sizeof (h->src_address));
   if (is_p2p)
     {
       clib_memcpy (h->dst_address, sub_sw->p2p.client_mac,
@@ -268,6 +268,27 @@ ethernet_update_adjacency (vnet_main_t * vnm, u32 sw_if_index, u32 ai)
     }
 }
 
+static void
+ethernet_interface_address_copy (ethernet_interface_address_t * dst,
+				 const u8 * mac)
+{
+  clib_memcpy (&dst->mac, (u8 *) mac, sizeof (dst->mac));
+  /*
+   * ethernet dataplane loads mac as u64, makes sure the last 2 bytes are 0
+   * for comparison purpose
+   */
+  dst->zero = 0;
+}
+
+static void
+ethernet_set_mac (vnet_hw_interface_t * hi, ethernet_interface_t * ei,
+		  const u8 * mac_address)
+{
+  vec_validate (hi->hw_address, sizeof (mac_address_t) - 1);
+  clib_memcpy (hi->hw_address, mac_address, sizeof (mac_address_t));
+  ethernet_interface_address_copy (&ei->address, mac_address);
+}
+
 static clib_error_t *
 ethernet_mac_change (vnet_hw_interface_t * hi,
 		     const u8 * old_address, const u8 * mac_address)
@@ -278,11 +299,7 @@ ethernet_mac_change (vnet_hw_interface_t * hi,
   em = &ethernet_main;
   ei = pool_elt_at_index (em->interfaces, hi->hw_instance);
 
-  vec_validate (hi->hw_address,
-		STRUCT_SIZE_OF (ethernet_header_t, src_address) - 1);
-  clib_memcpy (hi->hw_address, mac_address, vec_len (hi->hw_address));
-
-  clib_memcpy (ei->address, (u8 *) mac_address, sizeof (ei->address));
+  ethernet_set_mac (hi, ei, mac_address);
 
   {
     ethernet_address_change_ctx_t *cb;
@@ -362,9 +379,7 @@ ethernet_register_interface (vnet_main_t * vnm,
   /* Default ethernet MTU, 9000 unless set by ethernet_config see below */
   vnet_sw_interface_set_mtu (vnm, hi->sw_if_index, em->default_mtu);
 
-  clib_memcpy (ei->address, address, sizeof (ei->address));
-  vec_add (hi->hw_address, address, sizeof (ei->address));
-  CLIB_MEM_UNPOISON (hi->hw_address, 8);
+  ethernet_set_mac (hi, ei, address);
 
   if (error)
     {
@@ -979,7 +994,8 @@ ethernet_interface_add_del_address (ethernet_main_t * em,
 				    u8 is_add)
 {
   ethernet_interface_t *ei = ethernet_get_interface (em, hw_if_index);
-  mac_address_t *if_addr = 0;
+  ethernet_interface_address_t *if_addr = 0;
+  int found = 0;
 
   /* return if there is not an ethernet interface for this hw interface */
   if (!ei)
@@ -988,36 +1004,29 @@ ethernet_interface_add_del_address (ethernet_main_t * em,
   /* determine whether the address is configured on the interface */
   vec_foreach (if_addr, ei->secondary_addrs)
   {
-    if (!ethernet_mac_address_equal (if_addr->bytes, address))
-      continue;
-
-    break;
+    if (ethernet_mac_address_equal (if_addr->mac.bytes, address))
+      {
+	found = 1;
+	break;
+      }
   }
 
-  if (if_addr && vec_is_member (ei->secondary_addrs, if_addr))
+  if (is_add)
     {
-      /* delete found address */
-      if (!is_add)
-	{
-	  vec_delete (ei->secondary_addrs, 1, if_addr - ei->secondary_addrs);
-	  if_addr = 0;
-	}
-      /* address already found, so nothing needs to be done if adding */
-    }
-  else
-    {
-      /* if_addr could be 0 or past the end of the vector. reset to 0 */
-      if_addr = 0;
-
-      /* add new address */
-      if (is_add)
+      if (!found)
 	{
+	  /* address not found yet: add it */
 	  vec_add2 (ei->secondary_addrs, if_addr, 1);
-	  clib_memcpy (&if_addr->bytes, address, sizeof (if_addr->bytes));
+	  ethernet_interface_address_copy (if_addr, address);
 	}
+      return &if_addr->mac;
     }
 
-  return if_addr;
+  /* delete case */
+  if (found)
+    vec_delete (ei->secondary_addrs, 1, if_addr - ei->secondary_addrs);
+
+  return 0;
 }
 
 int
diff --git a/src/vnet/ethernet/node.c b/src/vnet/ethernet/node.c
index 73e9eec71ae..efe7290d19a 100644
--- a/src/vnet/ethernet/node.c
+++ b/src/vnet/ethernet/node.c
@@ -694,9 +694,11 @@ ethernet_input_inline_dmac_check (vnet_hw_interface_t * hi,
 				  u32 n_packets, ethernet_interface_t * ei,
 				  u8 have_sec_dmac)
 {
-  u64 hwaddr = (*(u64 *) hi->hw_address) & DMAC_MASK;
+  u64 hwaddr = ei->address.as_u64;
   u8 bad = 0;
 
+  ASSERT (0 == ei->address.zero);
+
   dmacs_bad[0] = is_dmac_bad (dmacs[0], hwaddr);
   dmacs_bad[1] = ((n_packets > 1) & is_dmac_bad (dmacs[1], hwaddr));
 
@@ -704,11 +706,12 @@ ethernet_input_inline_dmac_check (vnet_hw_interface_t * hi,
 
   if (PREDICT_FALSE (bad && have_sec_dmac))
     {
-      mac_address_t *sec_addr;
+      ethernet_interface_address_t *sec_addr;
 
       vec_foreach (sec_addr, ei->secondary_addrs)
       {
-	hwaddr = (*(u64 *) sec_addr) & DMAC_MASK;
+	ASSERT (0 == sec_addr->zero);
+	hwaddr = sec_addr->as_u64;
 
 	bad = (eth_input_sec_dmac_check_x1 (hwaddr, dmacs, dmacs_bad) |
 	       eth_input_sec_dmac_check_x1 (hwaddr, dmacs + 1,
@@ -726,12 +729,14 @@ eth_input_process_frame_dmac_check (vnet_hw_interface_t * hi,
 				    u32 n_packets, ethernet_interface_t * ei,
 				    u8 have_sec_dmac)
 {
-  u64 hwaddr = (*(u64 *) hi->hw_address) & DMAC_MASK;
+  u64 hwaddr = ei->address.as_u64;
   u64 *dmac = dmacs;
   u8 *dmac_bad = dmacs_bad;
   u32 bad = 0;
   i32 n_left = n_packets;
 
+  ASSERT (0 == ei->address.zero);
+
 #ifdef CLIB_HAVE_VEC256
   while (n_left > 0)
     {
@@ -760,15 +765,17 @@ eth_input_process_frame_dmac_check (vnet_hw_interface_t * hi,
 
   if (have_sec_dmac && bad)
     {
-      mac_address_t *addr;
+      ethernet_interface_address_t *addr;
 
       vec_foreach (addr, ei->secondary_addrs)
       {
-	u64 hwaddr = ((u64 *) addr)[0] & DMAC_MASK;
+	u64 hwaddr = addr->as_u64;
 	i32 n_left = n_packets;
 	u64 *dmac = dmacs;
 	u8 *dmac_bad = dmacs_bad;
 
+	ASSERT (0 == addr->zero);
+
 	bad = 0;
 
 	while (n_left > 0)