+extern vnet_feature_arc_registration_t vnet_feat_arc_ip4_local;
+
+static uword
+nat44_hairpinning_fn (vlib_main_t * vm,
+ vlib_node_runtime_t * node,
+ vlib_frame_t * frame)
+{
+ u32 n_left_from, * from, * to_next;
+ snat_in2out_next_t next_index;
+ u32 pkts_processed = 0;
+ snat_main_t * sm = &snat_main;
+ vnet_feature_main_t *fm = &feature_main;
+ u8 arc_index = vnet_feat_arc_ip4_local.feature_arc_index;
+ vnet_feature_config_main_t *cm = &fm->feature_config_mains[arc_index];
+
+ from = vlib_frame_vector_args (frame);
+ n_left_from = frame->n_vectors;
+ next_index = node->cached_next_index;
+
+ while (n_left_from > 0)
+ {
+ u32 n_left_to_next;
+
+ vlib_get_next_frame (vm, node, next_index,
+ to_next, n_left_to_next);
+
+ while (n_left_from > 0 && n_left_to_next > 0)
+ {
+ u32 bi0;
+ vlib_buffer_t * b0;
+ u32 next0;
+ ip4_header_t * ip0;
+ u32 proto0;
+ udp_header_t * udp0;
+ tcp_header_t * tcp0;
+
+ /* speculatively enqueue b0 to the current next frame */
+ bi0 = from[0];
+ to_next[0] = bi0;
+ from += 1;
+ to_next += 1;
+ n_left_from -= 1;
+ n_left_to_next -= 1;
+
+ b0 = vlib_get_buffer (vm, bi0);
+ ip0 = vlib_buffer_get_current (b0);
+ udp0 = ip4_next_header (ip0);
+ tcp0 = (tcp_header_t *) udp0;
+
+ proto0 = ip_proto_to_snat_proto (ip0->protocol);
+
+ vnet_get_config_data (&cm->config_main, &b0->current_config_index,
+ &next0, 0);
+
+ if (snat_hairpinning (sm, b0, ip0, udp0, tcp0, proto0))
+ next0 = SNAT_IN2OUT_NEXT_LOOKUP;
+
+ pkts_processed += next0 != SNAT_IN2OUT_NEXT_DROP;
+
+ /* verify speculative enqueue, maybe switch current next frame */
+ vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+ to_next, n_left_to_next,
+ bi0, next0);
+ }
+
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ }
+
+ vlib_node_increment_counter (vm, nat44_hairpinning_node.index,
+ SNAT_IN2OUT_ERROR_IN2OUT_PACKETS,
+ pkts_processed);
+ return frame->n_vectors;
+}
+
+VLIB_REGISTER_NODE (nat44_hairpinning_node) = {
+ .function = nat44_hairpinning_fn,
+ .name = "nat44-hairpinning",
+ .vector_size = sizeof (u32),
+ .type = VLIB_NODE_TYPE_INTERNAL,
+ .n_errors = ARRAY_LEN(snat_in2out_error_strings),
+ .error_strings = snat_in2out_error_strings,
+ .n_next_nodes = 2,
+ .next_nodes = {
+ [SNAT_IN2OUT_NEXT_DROP] = "error-drop",
+ [SNAT_IN2OUT_NEXT_LOOKUP] = "ip4-lookup",
+ },
+};
+
+VLIB_NODE_FUNCTION_MULTIARCH (nat44_hairpinning_node,
+ nat44_hairpinning_fn);
+