UDP Encapsulation.

A UDP-encap object that particiapates in the FIB graph and contributes
DPO to teh output chain. It thereofre resembles a tunnel but without the
interface. FIB paths (and henace routes) can then be created to egress
through the UDP-encap. Said routes can have MPLS labels, hence this also
allows MPLSoUPD.
Encap is uni-directional. For decap, one still registers with the UDP port
dispatcher.

Change-Id: I23bd345523b20789a1de1b02022ea1148ca50797
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 280 insertions, 0 deletions

diff --git a/src/vnet/udp/udp_encap_node.c b/src/vnet/udp/udp_encap_node.c
new file mode 100644
index 00000000000..09a76b530f6
--- /dev/null
+++ b/src/vnet/udp/udp_encap_node.c
@@ -0,0 +1,280 @@
+/*
+ * Copyright (c) 2017 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 <vnet/udp/udp_encap.h>
+
+typedef struct udp4_encap_trace_t_
+{
+  udp_header_t udp;
+  ip4_header_t ip;
+} udp4_encap_trace_t;
+
+typedef struct udp6_encap_trace_t_
+{
+  udp_header_t udp;
+  ip6_header_t ip;
+} udp6_encap_trace_t;
+
+static u8 *
+format_udp4_encap_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  udp4_encap_trace_t *t;
+
+  t = va_arg (*args, udp4_encap_trace_t *);
+
+  s = format (s, "%U\n  %U",
+	      format_ip4_header, &t->ip, sizeof (t->ip),
+	      format_udp_header, &t->udp, sizeof (t->udp));
+  return (s);
+}
+
+static u8 *
+format_udp6_encap_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  udp6_encap_trace_t *t;
+
+  t = va_arg (*args, udp6_encap_trace_t *);
+
+  s = format (s, "%U\n  %U",
+	      format_ip6_header, &t->ip, sizeof (t->ip),
+	      format_udp_header, &t->udp, sizeof (t->udp));
+  return (s);
+}
+
+always_inline uword
+udp_encap_inline (vlib_main_t * vm,
+		  vlib_node_runtime_t * node,
+		  vlib_frame_t * frame, int is_encap_v6)
+{
+  u32 *from = vlib_frame_vector_args (frame);
+  u32 n_left_from, n_left_to_next, *to_next, next_index;
+
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      while (n_left_from >= 4 && n_left_to_next >= 2)
+	{
+	  vlib_buffer_t *b0, *b1;
+	  udp_encap_t *ue0, *ue1;
+	  u32 bi0, next0, uei0;
+	  u32 bi1, next1, uei1;
+
+	  /* Prefetch next iteration. */
+	  {
+	    vlib_buffer_t *p2, *p3;
+
+	    p2 = vlib_get_buffer (vm, from[2]);
+	    p3 = vlib_get_buffer (vm, from[3]);
+
+	    vlib_prefetch_buffer_header (p2, STORE);
+	    vlib_prefetch_buffer_header (p3, STORE);
+	  }
+
+	  bi0 = to_next[0] = from[0];
+	  bi1 = to_next[1] = from[1];
+
+	  from += 2;
+	  n_left_from -= 2;
+	  to_next += 2;
+	  n_left_to_next -= 2;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+
+	  uei0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
+	  uei1 = vnet_buffer (b1)->ip.adj_index[VLIB_TX];
+
+	  /* Rewrite packet header and updates lengths. */
+	  ue0 = udp_encap_get (uei0);
+	  ue1 = udp_encap_get (uei1);
+
+	  /* Paint */
+	  if (is_encap_v6)
+	    {
+	      const u8 n_bytes =
+		sizeof (udp_header_t) + sizeof (ip6_header_t);
+	      ip_udp_encap_two (vm, b0, b1, (u8 *) & ue0->ue_hdrs,
+				(u8 *) & ue1->ue_hdrs, n_bytes, 0);
+	      if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+		{
+		  udp6_encap_trace_t *tr =
+		    vlib_add_trace (vm, node, b0, sizeof (*tr));
+		  tr->udp = ue0->ue_hdrs.ip6.ue_udp;
+		  tr->ip = ue0->ue_hdrs.ip6.ue_ip6;
+		}
+	      if (PREDICT_FALSE (b1->flags & VLIB_BUFFER_IS_TRACED))
+		{
+		  udp6_encap_trace_t *tr =
+		    vlib_add_trace (vm, node, b1, sizeof (*tr));
+		  tr->udp = ue1->ue_hdrs.ip6.ue_udp;
+		  tr->ip = ue1->ue_hdrs.ip6.ue_ip6;
+		}
+	    }
+	  else
+	    {
+	      const u8 n_bytes =
+		sizeof (udp_header_t) + sizeof (ip4_header_t);
+
+	      ip_udp_encap_two (vm, b0, b1,
+				(u8 *) & ue0->ue_hdrs,
+				(u8 *) & ue1->ue_hdrs, n_bytes, 1);
+
+	      if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+		{
+		  udp4_encap_trace_t *tr =
+		    vlib_add_trace (vm, node, b0, sizeof (*tr));
+		  tr->udp = ue0->ue_hdrs.ip4.ue_udp;
+		  tr->ip = ue0->ue_hdrs.ip4.ue_ip4;
+		}
+	      if (PREDICT_FALSE (b1->flags & VLIB_BUFFER_IS_TRACED))
+		{
+		  udp4_encap_trace_t *tr =
+		    vlib_add_trace (vm, node, b1, sizeof (*tr));
+		  tr->udp = ue1->ue_hdrs.ip4.ue_udp;
+		  tr->ip = ue1->ue_hdrs.ip4.ue_ip4;
+		}
+	    }
+
+	  next0 = ue0->ue_dpo.dpoi_next_node;
+	  next1 = ue1->ue_dpo.dpoi_next_node;
+	  vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ue0->ue_dpo.dpoi_index;
+	  vnet_buffer (b1)->ip.adj_index[VLIB_TX] = ue1->ue_dpo.dpoi_index;
+
+	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
+					   to_next, n_left_to_next,
+					   bi0, bi1, next0, next1);
+	}
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 bi0, next0, uei0;
+	  vlib_buffer_t *b0;
+	  udp_encap_t *ue0;
+
+	  bi0 = to_next[0] = from[0];
+
+	  from += 1;
+	  n_left_from -= 1;
+	  to_next += 1;
+	  n_left_to_next -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+
+	  uei0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
+
+	  /* Rewrite packet header and updates lengths. */
+	  ue0 = udp_encap_get (uei0);
+
+	  /* Paint */
+	  if (is_encap_v6)
+	    {
+	      const u8 n_bytes =
+		sizeof (udp_header_t) + sizeof (ip6_header_t);
+	      ip_udp_encap_one (vm, b0, (u8 *) & ue0->ue_hdrs.ip6, n_bytes,
+				0);
+
+	      if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+		{
+		  udp6_encap_trace_t *tr =
+		    vlib_add_trace (vm, node, b0, sizeof (*tr));
+		  tr->udp = ue0->ue_hdrs.ip6.ue_udp;
+		  tr->ip = ue0->ue_hdrs.ip6.ue_ip6;
+		}
+	    }
+	  else
+	    {
+	      const u8 n_bytes =
+		sizeof (udp_header_t) + sizeof (ip4_header_t);
+
+	      ip_udp_encap_one (vm, b0, (u8 *) & ue0->ue_hdrs.ip4, n_bytes,
+				1);
+
+	      if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+		{
+		  udp4_encap_trace_t *tr =
+		    vlib_add_trace (vm, node, b0, sizeof (*tr));
+		  tr->udp = ue0->ue_hdrs.ip4.ue_udp;
+		  tr->ip = ue0->ue_hdrs.ip4.ue_ip4;
+		}
+	    }
+
+	  next0 = ue0->ue_dpo.dpoi_next_node;
+	  vnet_buffer (b0)->ip.adj_index[VLIB_TX] = ue0->ue_dpo.dpoi_index;
+
+	  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 frame->n_vectors;
+}
+
+static uword
+udp4_encap (vlib_main_t * vm,
+	    vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return udp_encap_inline (vm, node, frame, 0);
+}
+
+static uword
+udp6_encap (vlib_main_t * vm,
+	    vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return udp_encap_inline (vm, node, frame, 1);
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (udp4_encap_node) = {
+  .function = udp4_encap,
+  .name = "udp4-encap",
+  .vector_size = sizeof (u32),
+
+  .format_trace = format_udp4_encap_trace,
+
+  .n_next_nodes = 0,
+};
+VLIB_NODE_FUNCTION_MULTIARCH (udp4_encap_node, udp4_encap);
+
+VLIB_REGISTER_NODE (udp6_encap_node) = {
+  .function = udp6_encap,
+  .name = "udp6-encap",
+  .vector_size = sizeof (u32),
+
+  .format_trace = format_udp6_encap_trace,
+
+  .n_next_nodes = 0,
+};
+VLIB_NODE_FUNCTION_MULTIARCH (udp6_encap_node, udp6_encap);
+/* *INDENT-ON* */
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */