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, 147 insertions, 0 deletions

diff --git a/src/vnet/udp/udp_encap.h b/src/vnet/udp/udp_encap.h
new file mode 100644
index 00000000000..b8f329dcbee
--- /dev/null
+++ b/src/vnet/udp/udp_encap.h
@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) 2016 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.
+ */
+
+#ifndef __UDP_ENCAP_H__
+#define __UDP_ENCAP_H__
+
+#include <vnet/ip/ip.h>
+#include <vnet/udp/udp.h>
+#include <vnet/fib/fib_node.h>
+
+/**
+ * UDP encapsualtion.
+ * A representation of the encapsulation of packets in UDP-over-IP.
+ * This is encapsulation only, there is no tunnel interface, hence
+ * it is uni-directional. For decap register a handler with the UDP port
+ * dispatcher.
+ */
+
+/**
+ * Fixup behaviour. Actions performed on the encap in the data-plance
+ */
+typedef enum udp_encap_fixup_flags_t_
+{
+  UDP_ENCAP_FIXUP_NONE = 0,
+    /**
+     * UDP source port contains an entropy/hash value for load-balancing by downstream peers.
+     */
+  UDP_ENCAP_FIXUP_UDP_SRC_PORT_ENTROPY = (1 << 0),
+} udp_encap_fixup_flags_t;
+
+/**
+ * The UDP encap represenation
+ */
+typedef struct udp_encap_t_
+{
+    /**
+     * The first cacheline contains the data used in the data-plane
+     */
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+
+    /**
+     * The headers to paint, in packet painting order
+     */
+  union
+  {
+    struct
+    {
+      ip4_header_t ue_ip4;
+      udp_header_t ue_udp;
+    } __attribute__ ((packed)) ip4;
+    struct
+    {
+      ip6_header_t ue_ip6;
+      udp_header_t ue_udp;
+    } __attribute__ ((packed)) ip6;
+  } __attribute__ ((packed)) ue_hdrs;
+
+    /**
+     * Flags controlling fixup behaviour
+     */
+  udp_encap_fixup_flags_t ue_flags;
+
+    /**
+     * The DPO used to forward to the next node in the VLIB graph
+     */
+  dpo_id_t ue_dpo;
+
+    /**
+     * the protocol of the IP header imposed
+     */
+  fib_protocol_t ue_ip_proto;
+
+    CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
+
+    /**
+     * linkage into the FIB graph
+     */
+  fib_node_t ue_fib_node;
+
+    /**
+     * The ID given by the user/client.
+     * This ID is used by the client for modifications.
+     */
+  u32 ue_id;
+
+    /**
+     * Tracking information for the IP destination
+     */
+  fib_node_index_t ue_fib_entry_index;
+  u32 ue_fib_sibling;
+
+    /**
+     * The FIB index in which the encap destination resides
+     */
+  index_t ue_fib_index;
+} udp_encap_t;
+
+extern index_t udp_encap_add_and_lock (u32 id,
+				       fib_protocol_t proto,
+				       index_t fib_index,
+				       const ip46_address_t * src_ip,
+				       const ip46_address_t * dst_ip,
+				       u16 src_port,
+				       u16 dst_port,
+				       udp_encap_fixup_flags_t flags);
+
+extern index_t udp_encap_find (u32 id);
+extern void udp_encap_lock (u32 id);
+extern void udp_encap_unlock (u32 id);
+extern u8 *format_udp_encap (u8 * s, va_list * args);
+extern void udp_encap_unlock_w_index (index_t uei);
+extern void udp_encap_contribute_forwarding (u32 id,
+					     dpo_proto_t proto,
+					     dpo_id_t * dpo);
+
+/**
+ * Pool of encaps
+ */
+extern udp_encap_t *udp_encap_pool;
+
+static inline udp_encap_t *
+udp_encap_get (index_t uei)
+{
+  return (pool_elt_at_index (udp_encap_pool, uei));
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
+
+#endif