gbp: add anonymous l3-out external interfaces

So far, GBP l3-out packets classification & policy relied on programmed
EP. All traffic to/from l3-out must go through a known EP.
This patch introduces a new feature where l3-out next-hops are only
known by their subnets (l3-out prefixes). As there are no longer known
EPs to program, an interface must be configured as external anonymous
l3-out. Packets classification & policy on this interface will rely on
the external subnets programmed in the BD VRF.
Note that contrary to all other interfaces in a GBP BD, external
anonymous l3-out interfaces have BD L2 learning turned on and rely on
ARP/ND.

Type: feature

Change-Id: Ieedb29dff4e967d08c4301e82d06bff450a63e5f
Signed-off-by: Benoît Ganne <bganne@cisco.com>

1 files changed, 43 insertions, 2 deletions

diff --git a/src/plugins/gbp/gbp_classify.h b/src/plugins/gbp/gbp_classify.h
index c0c1fd53dc5..ca7db94a2c0 100644
--- a/src/plugins/gbp/gbp_classify.h
+++ b/src/plugins/gbp/gbp_classify.h
@@ -19,16 +19,18 @@
 #define __GBP_CLASSIFY_H__
 
 #include <plugins/gbp/gbp.h>
+#include <vnet/ethernet/arp_packet.h>
 
 typedef enum gbp_src_classify_type_t_
 {
   GBP_SRC_CLASSIFY_NULL,
   GBP_SRC_CLASSIFY_PORT,
   GBP_SRC_CLASSIFY_LPM,
+  GBP_SRC_CLASSIFY_LPM_ANON,
+  GBP_SRC_N_CLASSIFY
+#define GBP_SRC_N_CLASSIFY GBP_SRC_N_CLASSIFY
 } gbp_src_classify_type_t;
 
-#define GBP_SRC_N_CLASSIFY (GBP_SRC_CLASSIFY_LPM + 1)
-
 /**
  * Grouping of global data for the GBP source EPG classification feature
  */
@@ -42,6 +44,45 @@ typedef struct gbp_src_classify_main_t_
 
 extern gbp_src_classify_main_t gbp_src_classify_main;
 
+enum gbp_classify_get_ip_way
+{
+  GBP_CLASSIFY_GET_IP_SRC = 0,
+  GBP_CLASSIFY_GET_IP_DST = 1
+};
+
+static_always_inline dpo_proto_t
+gbp_classify_get_ip_address (const ethernet_header_t * eh0,
+			     const ip4_address_t ** ip4,
+			     const ip6_address_t ** ip6,
+			     const enum gbp_classify_get_ip_way way)
+{
+  u16 etype = clib_net_to_host_u16 (eh0->type);
+  const void *l3h0 = eh0 + 1;
+
+  if (ETHERNET_TYPE_VLAN == etype)
+    {
+      const ethernet_vlan_header_t *vh0 =
+	(ethernet_vlan_header_t *) (eh0 + 1);
+      etype = clib_net_to_host_u16 (vh0->type);
+      l3h0 = vh0 + 1;
+    }
+
+  switch (etype)
+    {
+    case ETHERNET_TYPE_IP4:
+      *ip4 = &(&((const ip4_header_t *) l3h0)->src_address)[way];
+      return DPO_PROTO_IP4;
+    case ETHERNET_TYPE_IP6:
+      *ip6 = &(&((const ip6_header_t *) l3h0)->src_address)[way];
+      return DPO_PROTO_IP6;
+    case ETHERNET_TYPE_ARP:
+      *ip4 = &((ethernet_arp_header_t *) l3h0)->ip4_over_ethernet[way].ip4;
+      return DPO_PROTO_IP4;
+    }
+
+  return DPO_PROTO_NONE;
+}
+
 #endif
 
 /*