+typedef struct mpls_frag_trace_t_
+{
+ u16 pkt_size;
+ u16 mtu;
+} mpls_frag_trace_t;
+
+typedef enum
+{
+ MPLS_FRAG_NEXT_REWRITE,
+ MPLS_FRAG_NEXT_REWRITE_MIDCHAIN,
+ MPLS_FRAG_NEXT_ICMP_ERROR,
+ MPLS_FRAG_NEXT_DROP,
+ MPLS_FRAG_N_NEXT,
+} mpls_frag_next_t;
+
+static uword
+mpls_frag (vlib_main_t * vm,
+ vlib_node_runtime_t * node,
+ vlib_frame_t * frame)
+{
+ u32 n_left_from, next_index, * from, * to_next, n_left_to_next, *frags;
+ vlib_node_runtime_t * error_node;
+
+ error_node = vlib_node_get_runtime (vm, mpls_output_node.index);
+ from = vlib_frame_vector_args (frame);
+ n_left_from = frame->n_vectors;
+ next_index = node->cached_next_index;
+ frags = NULL;
+
+ while (n_left_from > 0)
+ {
+ vlib_get_next_frame (vm, node, next_index,
+ to_next, n_left_to_next);
+
+ while (n_left_from > 0 && n_left_to_next > 0)
+ {
+ ip_adjacency_t * adj0;
+ vlib_buffer_t * p0;
+ mpls_frag_next_t next0;
+ u32 pi0, adj_index0;
+ ip_frag_error_t error0 = IP_FRAG_ERROR_NONE;
+ i16 encap_size;
+ u8 is_ip4;
+
+ pi0 = to_next[0] = from[0];
+ p0 = vlib_get_buffer (vm, pi0);
+ from += 1;
+ n_left_from -= 1;
+ is_ip4 = vnet_buffer (p0)->mpls.pyld_proto == DPO_PROTO_IP4;
+
+ adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
+ adj0 = adj_get(adj_index0);
+
+ /* the size of the MPLS stack */
+ encap_size = vnet_buffer(p0)->l3_hdr_offset - p0->current_data;
+
+ /* IP fragmentation */
+ if (is_ip4)
+ error0 = ip4_frag_do_fragment (vm, pi0,
+ adj0->rewrite_header.max_l3_packet_bytes,
+ encap_size, &frags);
+ else
+ error0 = ip6_frag_do_fragment (vm, pi0,
+ adj0->rewrite_header.max_l3_packet_bytes,
+ encap_size, &frags);
+
+ if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED))
+ {
+ mpls_frag_trace_t *tr =
+ vlib_add_trace (vm, node, p0, sizeof (*tr));
+ tr->mtu = adj0->rewrite_header.max_l3_packet_bytes;
+ tr->pkt_size = vlib_buffer_length_in_chain(vm, p0);
+ }
+
+ if (PREDICT_TRUE(error0 == IP_FRAG_ERROR_NONE))
+ {
+ /* Free original buffer chain */
+ vlib_buffer_free_one (vm, pi0); /* Free original packet */
+ next0 = (IP_LOOKUP_NEXT_MIDCHAIN == adj0->lookup_next_index ?
+ MPLS_FRAG_NEXT_REWRITE_MIDCHAIN :
+ MPLS_FRAG_NEXT_REWRITE);
+ }
+ else if (is_ip4 && error0 == IP_FRAG_ERROR_DONT_FRAGMENT_SET)
+ {
+ icmp4_error_set_vnet_buffer (
+ p0, ICMP4_destination_unreachable,
+ ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set,
+ vnet_buffer (p0)->ip_frag.mtu);
+ next0 = MPLS_FRAG_NEXT_ICMP_ERROR;
+ }
+ else
+ {
+ vlib_error_count (vm, mpls_output_node.index, error0, 1);
+ vec_add1 (frags, pi0); /* Get rid of the original buffer */
+ next0 = MPLS_FRAG_NEXT_DROP;
+ }
+
+ /* Send fragments that were added in the frame */
+ u32 *frag_from, frag_left;
+
+ frag_from = frags;
+ frag_left = vec_len (frags);
+
+ while (frag_left > 0)
+ {
+ while (frag_left > 0 && n_left_to_next > 0)
+ {
+ u32 i;
+ i = to_next[0] = frag_from[0];
+ frag_from += 1;
+ frag_left -= 1;
+ to_next += 1;
+ n_left_to_next -= 1;
+
+ p0 = vlib_get_buffer (vm, i);
+ p0->error = error_node->errors[error0];
+
+ vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+ to_next, n_left_to_next, i,
+ next0);
+ }
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ vlib_get_next_frame (vm, node, next_index, to_next,
+ n_left_to_next);
+ }
+ vec_reset_length (frags);
+ }
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ }
+ vec_free (frags);
+
+ return frame->n_vectors;
+}
+
+static u8 *
+format_mpls_frag_trace (u8 * s, va_list * args)
+{
+ CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+ CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+ mpls_frag_trace_t *t = va_arg (*args, mpls_frag_trace_t *);
+
+ s = format (s, "mtu:%d pkt-size:%d", t->mtu, t->pkt_size);
+ return s;
+}
+
+VLIB_REGISTER_NODE (mpls_frag_node) = {
+ .function = mpls_frag,
+ .name = "mpls-frag",
+ .vector_size = sizeof (u32),
+ .format_trace = format_mpls_frag_trace,
+ .type = VLIB_NODE_TYPE_INTERNAL,
+
+ .n_errors = IP_FRAG_N_ERROR,
+ .error_strings = mpls_frag_error_strings,
+
+ .n_next_nodes = MPLS_FRAG_N_NEXT,
+ .next_nodes = {
+ [MPLS_FRAG_NEXT_REWRITE] = "mpls-output",
+ [MPLS_FRAG_NEXT_REWRITE_MIDCHAIN] = "mpls-midchain",
+ [MPLS_FRAG_NEXT_ICMP_ERROR] = "ip4-icmp-error",
+ [MPLS_FRAG_NEXT_DROP] = "mpls-drop"
+ },
+};
+
+/*