diff --git a/src/vnet/tunnel/tunnel_dp.h b/src/vnet/tunnel/tunnel_dp.h
new file mode 100644
index 0000000..3e3a813
--- /dev/null
+++ b/src/vnet/tunnel/tunnel_dp.h
@@ -0,0 +1,104 @@
+/*
+ * tunnel_dp.h: data-plane functions tunnels.
+ *
+ * Copyright (c) 2019 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 __TUNNEL_DP_H__
+#define __TUNNEL_DP_H__
+
+static_always_inline void
+tunnel_encap_fixup_4o4 (tunnel_encap_decap_flags_t flags,
+			const ip4_header_t * inner, ip4_header_t * outer)
+{
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
+    ip4_header_set_dscp (outer, ip4_header_get_dscp (inner));
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
+    ip4_header_set_ecn (outer, ip4_header_get_ecn (inner));
+  if ((flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DF) &&
+      ip4_header_get_df (inner))
+    ip4_header_set_df (outer);
+}
+
+static_always_inline void
+tunnel_encap_fixup_6o4 (tunnel_encap_decap_flags_t flags,
+			const ip6_header_t * inner, ip4_header_t * outer)
+{
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
+    ip4_header_set_dscp (outer, ip6_dscp_network_order (inner));
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
+    ip4_header_set_ecn (outer, ip6_ecn_network_order ((inner)));
+}
+
+static_always_inline void
+tunnel_encap_fixup_6o6 (tunnel_encap_decap_flags_t flags,
+			const ip6_header_t * inner, ip6_header_t * outer)
+{
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
+    ip6_set_dscp_network_order (outer, ip6_dscp_network_order (inner));
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
+    ip6_set_ecn_network_order (outer, ip6_ecn_network_order (inner));
+}
+
+static_always_inline void
+tunnel_encap_fixup_4o6 (tunnel_encap_decap_flags_t flags,
+			const ip4_header_t * inner, ip6_header_t * outer)
+{
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
+    ip6_set_dscp_network_order (outer, ip4_header_get_dscp (inner));
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
+    ip6_set_ecn_network_order (outer, ip4_header_get_ecn (inner));
+}
+
+static_always_inline void
+tunnel_decap_fixup_4o6 (tunnel_encap_decap_flags_t flags,
+			ip4_header_t * inner, const ip6_header_t * outer)
+{
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN)
+    ip4_header_set_ecn_w_chksum (inner, ip6_ecn_network_order (outer));
+}
+
+static_always_inline void
+tunnel_decap_fixup_6o6 (tunnel_encap_decap_flags_t flags,
+			ip6_header_t * inner, const ip6_header_t * outer)
+{
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN)
+    ip6_set_ecn_network_order (inner, ip6_ecn_network_order (outer));
+}
+
+static_always_inline void
+tunnel_decap_fixup_6o4 (tunnel_encap_decap_flags_t flags,
+			ip6_header_t * inner, const ip4_header_t * outer)
+{
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN)
+    ip6_set_ecn_network_order (inner, ip4_header_get_ecn (outer));
+}
+
+static_always_inline void
+tunnel_decap_fixup_4o4 (tunnel_encap_decap_flags_t flags,
+			ip4_header_t * inner, const ip4_header_t * outer)
+{
+  if (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN)
+    ip4_header_set_ecn_w_chksum (inner, ip4_header_get_ecn (outer));
+}
+
+#endif
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */