diff --git a/src/vnet/adj/adj_dp.h b/src/vnet/adj/adj_dp.h
new file mode 100644
index 0000000..27c0581
--- /dev/null
+++ b/src/vnet/adj/adj_dp.h
@@ -0,0 +1,66 @@
+/*
+ * 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 __ADJ_DP_H__
+#define __ADJ_DP_H__
+
+#include <vnet/adj/adj.h>
+#include <vnet/tunnel/tunnel_dp.h>
+
+static_always_inline void
+adj_midchain_ipip44_fixup (vlib_main_t * vm,
+                           const ip_adjacency_t * adj,
+                           vlib_buffer_t * b)
+{
+  tunnel_encap_decap_flags_t flags;
+  ip4_header_t *ip4;
+
+  flags = pointer_to_uword (adj->sub_type.midchain.fixup_data);
+
+  ip4 = vlib_buffer_get_current (b);
+  ip4->length = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b));
+
+  if (PREDICT_TRUE(TUNNEL_ENCAP_DECAP_FLAG_NONE == flags))
+  {
+      ip_csum_t sum;
+      u16 old,new;
+
+      old = 0;
+      new = ip4->length;
+
+      sum = ip4->checksum;
+      sum = ip_csum_update (sum, old, new, ip4_header_t, length);
+      ip4->checksum = ip_csum_fold (sum);
+  }
+  else
+  {
+      tunnel_encap_fixup_4o4 (flags, ip4 + 1, ip4);
+      ip4->checksum = ip4_header_checksum (ip4);
+  }
+}
+
+static_always_inline void
+adj_midchain_fixup (vlib_main_t *vm,
+                    const ip_adjacency_t *adj,
+                    vlib_buffer_t * b)
+{
+    if (PREDICT_TRUE(adj->rewrite_header.flags & VNET_REWRITE_FIXUP_IP4_O_4))
+        adj_midchain_ipip44_fixup (vm, adj, b);
+    else if (adj->sub_type.midchain.fixup_func)
+        adj->sub_type.midchain.fixup_func
+            (vm, adj, b, adj->sub_type.midchain.fixup_data);
+}
+
+#endif