diff --git a/extras/libmemif/src/memif.h b/extras/libmemif/src/memif.h
new file mode 100644
index 0000000..11918ea
--- /dev/null
+++ b/extras/libmemif/src/memif.h
@@ -0,0 +1,185 @@
+/*
+ *------------------------------------------------------------------
+ * 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.
+ *------------------------------------------------------------------
+ */
+
+#ifndef _MEMIF_H_
+#define _MEMIF_H_
+
+#ifndef MEMIF_CACHELINE_SIZE
+#define MEMIF_CACHELINE_SIZE 64
+#endif
+
+#define MEMIF_COOKIE		0x3E31F10
+#define MEMIF_VERSION_MAJOR	1
+#define MEMIF_VERSION_MINOR	0
+#define MEMIF_VERSION		((MEMIF_VERSION_MAJOR << 8) | MEMIF_VERSION_MINOR)
+
+/*
+ *  Type definitions
+ */
+
+typedef enum memif_msg_type
+{
+  MEMIF_MSG_TYPE_NONE = 0,
+  MEMIF_MSG_TYPE_ACK = 1,
+  MEMIF_MSG_TYPE_HELLO = 2,
+  MEMIF_MSG_TYPE_INIT = 3,
+  MEMIF_MSG_TYPE_ADD_REGION = 4,
+  MEMIF_MSG_TYPE_ADD_RING = 5,
+  MEMIF_MSG_TYPE_CONNECT = 6,
+  MEMIF_MSG_TYPE_CONNECTED = 7,
+  MEMIF_MSG_TYPE_DISCONNECT = 8,
+} memif_msg_type_t;
+
+typedef enum
+{
+  MEMIF_RING_S2M = 0,
+  MEMIF_RING_M2S = 1
+} memif_ring_type_t;
+
+typedef enum
+{
+  MEMIF_INTERFACE_MODE_ETHERNET = 0,
+  MEMIF_INTERFACE_MODE_IP = 1,
+  MEMIF_INTERFACE_MODE_PUNT_INJECT = 2,
+} memif_interface_mode_t;
+
+typedef uint16_t memif_region_index_t;
+typedef uint64_t memif_region_offset_t;
+typedef uint64_t memif_region_size_t;
+typedef uint16_t memif_ring_index_t;
+typedef uint32_t memif_interface_id_t;
+typedef uint16_t memif_version_t;
+typedef uint8_t memif_log2_ring_size_t;
+
+/*
+ *  Socket messages
+ */
+
+typedef struct __attribute__ ((packed))
+{
+  uint8_t name[32];
+  memif_version_t min_version;
+  memif_version_t max_version;
+  memif_region_index_t max_region;
+  memif_ring_index_t max_m2s_ring;
+  memif_ring_index_t max_s2m_ring;
+  memif_log2_ring_size_t max_log2_ring_size;
+} memif_msg_hello_t;
+
+typedef struct __attribute__ ((packed))
+{
+  memif_version_t version;
+  memif_interface_id_t id;
+  memif_interface_mode_t mode:8;
+  uint8_t secret[24];
+  uint8_t name[32];
+} memif_msg_init_t;
+
+typedef struct __attribute__ ((packed))
+{
+  memif_region_index_t index;
+  memif_region_size_t size;
+} memif_msg_add_region_t;
+
+typedef struct __attribute__ ((packed))
+{
+  uint16_t flags;
+#define MEMIF_MSG_ADD_RING_FLAG_S2M	(1 << 0)
+  memif_ring_index_t index;
+  memif_region_index_t region;
+  memif_region_offset_t offset;
+  memif_log2_ring_size_t log2_ring_size;
+} memif_msg_add_ring_t;
+
+typedef struct __attribute__ ((packed))
+{
+  uint8_t if_name[32];
+} memif_msg_connect_t;
+
+typedef struct __attribute__ ((packed))
+{
+  uint8_t if_name[32];
+} memif_msg_connected_t;
+
+typedef struct __attribute__ ((packed))
+{
+  uint32_t code;
+  uint8_t string[96];
+} memif_msg_disconnect_t;
+
+typedef struct __attribute__ ((packed, aligned (128)))
+{
+  memif_msg_type_t type:16;
+  union
+  {
+    memif_msg_hello_t hello;
+    memif_msg_init_t init;
+    memif_msg_add_region_t add_region;
+    memif_msg_add_ring_t add_ring;
+    memif_msg_connect_t connect;
+    memif_msg_connected_t connected;
+    memif_msg_disconnect_t disconnect;
+  };
+} memif_msg_t;
+
+_Static_assert (sizeof (memif_msg_t) == 128,
+		"Size of memif_msg_t must be 128");
+
+/*
+ *  Ring and Descriptor Layout
+ */
+
+typedef struct __attribute__ ((packed))
+{
+  uint16_t flags;
+#define MEMIF_DESC_FLAG_NEXT (1 << 0)
+  memif_region_index_t region;
+  uint32_t buffer_length;
+  uint32_t length;
+  uint8_t reserved[4];
+  memif_region_offset_t offset;
+  uint64_t metadata;
+} memif_desc_t;
+
+_Static_assert (sizeof (memif_desc_t) == 32,
+		"Size of memif_dsct_t must be 32");
+
+#define MEMIF_CACHELINE_ALIGN_MARK(mark) \
+  uint8_t mark[0] __attribute__((aligned(MEMIF_CACHELINE_SIZE)))
+
+typedef struct
+{
+  MEMIF_CACHELINE_ALIGN_MARK (cacheline0);
+  uint32_t cookie;
+  uint16_t flags;
+#define MEMIF_RING_FLAG_MASK_INT 1
+  volatile uint16_t head;
+    MEMIF_CACHELINE_ALIGN_MARK (cacheline1);
+  volatile uint16_t tail;
+    MEMIF_CACHELINE_ALIGN_MARK (cacheline2);
+  memif_desc_t desc[0];
+} memif_ring_t;
+
+#endif /* _MEMIF_H_ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */