VPP-470: Introduce VxLAN-GPE as transport for iOAM.

This is the second of the two commits. This commit introduces VxLAN-GPE
transit functionality.

Change-Id: I12f13e00f456df0047f2b7a0737addfeb683c420
Signed-off-by: Vengada Govindan <venggovi@cisco.com>

1 files changed, 188 insertions, 0 deletions

diff --git a/plugins/ioam-plugin/ioam/lib-vxlan-gpe/ioam_transit.c b/plugins/ioam-plugin/ioam/lib-vxlan-gpe/ioam_transit.c
new file mode 100644
index 00000000000..b42c357c79b
--- /dev/null
+++ b/plugins/ioam-plugin/ioam/lib-vxlan-gpe/ioam_transit.c
@@ -0,0 +1,188 @@
+ /*
+  * Copyright (c) 2015 Cisco and/or its affiliates.
+  * Licensed under the Apache License, Version 2.0 (the "License");
+  * you may not use this file except in compliance with the License.
+  * You may obtain a copy of the License at:
+  *
+  *     http://www.apache.org/licenses/LICENSE-2.0
+  *
+  * Unless required by applicable law or agreed to in writing, software
+  * distributed under the License is distributed on an "AS IS" BASIS,
+  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  * See the License for the specific language governing permissions and
+  * limitations under the License.
+  */
+#include <vppinfra/error.h>
+#include <vppinfra/hash.h>
+#include <vnet/vnet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ip/udp.h>
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/vxlan-gpe/vxlan_gpe.h>
+#include <ioam/lib-vxlan-gpe/vxlan_gpe_ioam_packet.h>
+#include <ioam/lib-vxlan-gpe/vxlan_gpe_ioam.h>
+#include <ioam/lib-vxlan-gpe/vxlan_gpe_ioam_util.h>
+#include <vnet/fib/ip6_fib.h>
+#include <vnet/fib/ip4_fib.h>
+#include <vnet/fib/fib_entry.h>
+
+/* Statistics (not really errors) */
+#define foreach_vxlan_gpe_transit_ioam_error    \
+_(ENCAPSULATED, "good packets encapsulated")
+
+static char *vxlan_gpe_transit_ioam_error_strings[] = {
+#define _(sym,string) string,
+  foreach_vxlan_gpe_transit_ioam_error
+#undef _
+};
+
+typedef enum
+{
+#define _(sym,str) VXLAN_GPE_TRANSIT_IOAM_ERROR_##sym,
+  foreach_vxlan_gpe_transit_ioam_error
+#undef _
+    VXLAN_GPE_TRANSIT_IOAM_N_ERROR,
+} vxlan_gpe_transit_ioam_error_t;
+
+typedef enum
+{
+  VXLAN_GPE_TRANSIT_IOAM_NEXT_OUTPUT,
+  VXLAN_GPE_TRANSIT_IOAM_NEXT_DROP,
+  VXLAN_GPE_TRANSIT_IOAM_N_NEXT
+} vxlan_gpe_transit_ioam_next_t;
+
+
+/* *INDENT-OFF* */
+VNET_FEATURE_INIT (vxlan_gpe_transit_ioam, static) =
+{
+  .arc_name = "ip4-output",
+  .node_name = "vxlan-gpe-transit-ioam",
+  .runs_before = VNET_FEATURES ("interface-output"),
+};
+/* *INDENT-ON* */
+
+static uword
+vxlan_gpe_transit_ioam (vlib_main_t * vm,
+			vlib_node_runtime_t * node, vlib_frame_t * from_frame)
+{
+  u32 n_left_from, next_index, *from, *to_next;
+
+  from = vlib_frame_vector_args (from_frame);
+  n_left_from = from_frame->n_vectors;
+
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 bi0;
+	  vlib_buffer_t *b0;
+	  u32 next0 = VXLAN_GPE_TRANSIT_IOAM_NEXT_OUTPUT;
+
+	  bi0 = from[0];
+	  to_next[0] = bi0;
+	  from += 1;
+	  to_next += 1;
+	  n_left_from -= 1;
+	  n_left_to_next -= 1;
+	  ip4_header_t *ip0;
+	  u32 iph_offset = 0;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  iph_offset = vnet_buffer (b0)->ip.save_rewrite_length;
+	  ip0 = (ip4_header_t *) ((u8 *) vlib_buffer_get_current (b0)
+				  + iph_offset);
+
+	  /* just forward non ipv4 packets */
+	  if (PREDICT_FALSE
+	      ((ip0->ip_version_and_header_length & 0xF0) == 0x40))
+	    {
+	      /* ipv4 packets */
+	      udp_header_t *udp_hdr0 = (udp_header_t *) (ip0 + 1);
+	      if (PREDICT_FALSE
+		  ((ip0->protocol == IP_PROTOCOL_UDP) &&
+		   (clib_net_to_host_u16 (udp_hdr0->dst_port) ==
+		    UDP_DST_PORT_vxlan_gpe)))
+		{
+
+		  /* Check the iOAM header */
+		  vxlan_gpe_header_t *gpe_hdr0 =
+		    (vxlan_gpe_header_t *) (udp_hdr0 + 1);
+
+		  if (PREDICT_FALSE
+		      (gpe_hdr0->protocol == VXLAN_GPE_PROTOCOL_IOAM))
+		    {
+		      uword *t = NULL;
+		      vxlan_gpe_ioam_main_t *hm = &vxlan_gpe_ioam_main;
+		      fib_prefix_t key4;
+		      memset (&key4, 0, sizeof (key4));
+		      key4.fp_proto = FIB_PROTOCOL_IP4;
+		      key4.fp_addr.ip4.as_u32 = ip0->dst_address.as_u32;
+		      t = hash_get_mem (hm->dst_by_ip4, &key4);
+		      if (t)
+			{
+
+
+			  vlib_buffer_advance (b0,
+					       (word) (sizeof
+						       (ethernet_header_t)));
+			  vxlan_gpe_encap_decap_ioam_v4_one_inline (vm, node,
+								    b0,
+								    &next0,
+								    VXLAN_GPE_TRANSIT_IOAM_NEXT_DROP,
+								    1
+								    /* use_adj */
+			    );
+			  vlib_buffer_advance (b0,
+					       -(word) (sizeof
+							(ethernet_header_t)));
+			}
+		    }
+		}
+	    }
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, next0);
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return from_frame->n_vectors;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (vxlan_gpe_transit_ioam_node) = {
+  .function = vxlan_gpe_transit_ioam,
+  .name = "vxlan-gpe-transit-ioam",
+  .vector_size = sizeof (u32),
+  .format_trace = format_vxlan_gpe_ioam_v4_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+
+  .n_errors = ARRAY_LEN(vxlan_gpe_transit_ioam_error_strings),
+  .error_strings = vxlan_gpe_transit_ioam_error_strings,
+
+  .n_next_nodes = VXLAN_GPE_TRANSIT_IOAM_N_NEXT,
+
+  .next_nodes = {
+        [VXLAN_GPE_TRANSIT_IOAM_NEXT_OUTPUT] = "interface-output",
+        [VXLAN_GPE_TRANSIT_IOAM_NEXT_DROP] = "error-drop",
+  },
+
+};
+/* *INDENT-ON* */
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */