+extern uword unformat_tunnel_encap_decap_flags (unformat_input_t *input,
+ va_list *args);
+
+#define foreach_tunnel_flag \
+ _ (RESOLVED, 0, "resolved") \
+ _ (TRACK_MTU, 1, "track-mtu")
+
+typedef enum tunnel_flags_t_
+{
+ TUNNEL_FLAG_NONE = 0,
+#define _(n, b, s) TUNNEL_FLAG_##n = (1 << b),
+ foreach_tunnel_flag
+#undef _
+} __clib_packed tunnel_flags_t;
+
+extern const u8 TUNNEL_FLAG_MASK;
+
+extern u8 *format_tunnel_flags (u8 *s, va_list *args);
+extern uword unformat_tunnel_flags (unformat_input_t *input, va_list *args);
+
+/**
+ * A representation of an IP tunnel config
+ */
+typedef struct tunnel_t_
+{
+ ip_address_t t_src;
+ ip_address_t t_dst;
+ tunnel_encap_decap_flags_t t_encap_decap_flags;
+ tunnel_flags_t t_flags;
+ tunnel_mode_t t_mode;
+ u32 t_table_id;
+ ip_dscp_t t_dscp;
+ u8 t_hop_limit;
+
+ /**
+ * derived data
+ */
+ u32 t_fib_index;
+
+ fib_node_index_t t_fib_entry_index;
+ u32 t_sibling;
+
+} tunnel_t;
+
+extern u8 *format_tunnel (u8 *s, va_list *args);
+extern uword unformat_tunnel (unformat_input_t *input, va_list *args);
+
+extern void tunnel_copy (const tunnel_t *src, tunnel_t *dst);
+extern int tunnel_resolve (tunnel_t *t, fib_node_type_t child_type,
+ index_t child_index);
+extern void tunnel_unresolve (tunnel_t *t);
+
+extern ip_address_family_t tunnel_get_af (const tunnel_t *t);
+
+extern void tunnel_contribute_forwarding (const tunnel_t *t, dpo_id_t *dpo);
+
+extern void tunnel_build_v6_hdr (const tunnel_t *t, ip_protocol_t next_proto,
+ ip6_header_t *ip);
+extern void tunnel_build_v4_hdr (const tunnel_t *t, ip_protocol_t next_proto,
+ ip4_header_t *ip);