nat: deal with flows instead of sessions
[vpp.git] / src / plugins / nat / nat44_classify.c
index b6ce4d7..85f8c64 100644 (file)
 #include <vnet/vnet.h>
 #include <vnet/fib/ip4_fib.h>
 #include <nat/nat.h>
-#include <nat/nat_reass.h>
 #include <nat/nat_inlines.h>
+#include <nat/nat44/ed_inlines.h>
 
 #define foreach_nat44_classify_error                      \
-_(MAX_REASS, "Maximum reassemblies exceeded")             \
-_(MAX_FRAG, "Maximum fragments per reassembly exceeded")  \
 _(NEXT_IN2OUT, "next in2out")                             \
 _(NEXT_OUT2IN, "next out2in")                             \
 _(FRAG_CACHED, "fragment cached")
@@ -87,10 +85,7 @@ nat44_classify_node_fn_inline (vlib_main_t * vm,
   nat44_classify_next_t next_index;
   snat_main_t *sm = &snat_main;
   snat_static_mapping_t *m;
-  u32 thread_index = vm->thread_index;
-  u32 *fragments_to_drop = 0;
-  u32 *fragments_to_loopback = 0;
-  u32 next_in2out = 0, next_out2in = 0, frag_cached = 0;
+  u32 next_in2out = 0, next_out2in = 0;
 
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
@@ -109,11 +104,7 @@ nat44_classify_node_fn_inline (vlib_main_t * vm,
          u32 next0 = NAT44_CLASSIFY_NEXT_IN2OUT;
          ip4_header_t *ip0;
          snat_address_t *ap;
-         snat_session_key_t m_key0;
          clib_bihash_kv_8_8_t kv0, value0;
-         udp_header_t *udp0;
-         nat_reass_ip4_t *reass0;
-         u8 cached0 = 0;
 
          /* speculatively enqueue b0 to the current next frame */
          bi0 = from[0];
@@ -125,7 +116,6 @@ nat44_classify_node_fn_inline (vlib_main_t * vm,
 
          b0 = vlib_get_buffer (vm, bi0);
          ip0 = vlib_buffer_get_current (b0);
-         udp0 = ip4_next_header (ip0);
 
           /* *INDENT-OFF* */
           vec_foreach (ap, sm->addresses)
@@ -140,11 +130,7 @@ nat44_classify_node_fn_inline (vlib_main_t * vm,
 
          if (PREDICT_FALSE (pool_elts (sm->static_mappings)))
            {
-             m_key0.addr = ip0->dst_address;
-             m_key0.port = 0;
-             m_key0.protocol = 0;
-             m_key0.fib_index = 0;
-             kv0.key = m_key0.as_u64;
+             init_nat_k (&kv0, ip0->dst_address, 0, 0, 0);
              /* try to classify the fragment based on IP header alone */
              if (!clib_bihash_search_8_8 (&sm->static_mapping_by_external,
                                           &kv0, &value0))
@@ -154,87 +140,15 @@ nat44_classify_node_fn_inline (vlib_main_t * vm,
                    next0 = NAT44_CLASSIFY_NEXT_OUT2IN;
                  goto enqueue0;
                }
-             if (!ip4_is_fragment (ip0) || ip4_is_first_fragment (ip0))
+             init_nat_k (&kv0, ip0->dst_address,
+                         vnet_buffer (b0)->ip.reass.l4_dst_port, 0,
+                         ip_proto_to_nat_proto (ip0->protocol));
+             if (!clib_bihash_search_8_8
+                 (&sm->static_mapping_by_external, &kv0, &value0))
                {
-                 /* process leading fragment/whole packet (with L4 header) */
-                 m_key0.port = clib_net_to_host_u16 (udp0->dst_port);
-                 m_key0.protocol = ip_proto_to_snat_proto (ip0->protocol);
-                 kv0.key = m_key0.as_u64;
-                 if (!clib_bihash_search_8_8
-                     (&sm->static_mapping_by_external, &kv0, &value0))
-                   {
-                     m =
-                       pool_elt_at_index (sm->static_mappings, value0.value);
-                     if (m->local_addr.as_u32 != m->external_addr.as_u32)
-                       next0 = NAT44_CLASSIFY_NEXT_OUT2IN;
-                   }
-                 if (ip4_is_fragment (ip0))
-                   {
-                     reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
-                                                            ip0->dst_address,
-                                                            ip0->fragment_id,
-                                                            ip0->protocol,
-                                                            1,
-                                                            &fragments_to_drop);
-                     if (PREDICT_FALSE (!reass0))
-                       {
-                         next0 = NAT44_CLASSIFY_NEXT_DROP;
-                         b0->error =
-                           node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
-                         nat_elog_notice ("maximum reassemblies exceeded");
-                         goto enqueue0;
-                       }
-                     /* save classification for future fragments and set past
-                      * fragments to be looped over and reprocessed */
-                     if (next0 == NAT44_CLASSIFY_NEXT_OUT2IN)
-                       reass0->classify_next =
-                         NAT_REASS_IP4_CLASSIFY_NEXT_OUT2IN;
-                     else
-                       reass0->classify_next =
-                         NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT;
-                     nat_ip4_reass_get_frags (reass0,
-                                              &fragments_to_loopback);
-                   }
-               }
-             else
-               {
-                 /* process non-first fragment */
-                 reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
-                                                        ip0->dst_address,
-                                                        ip0->fragment_id,
-                                                        ip0->protocol,
-                                                        1,
-                                                        &fragments_to_drop);
-                 if (PREDICT_FALSE (!reass0))
-                   {
-                     next0 = NAT44_CLASSIFY_NEXT_DROP;
-                     b0->error =
-                       node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
-                     nat_elog_notice ("maximum reassemblies exceeded");
-                     goto enqueue0;
-                   }
-                 if (reass0->classify_next == NAT_REASS_IP4_CLASSIFY_NONE)
-                   /* first fragment still hasn't arrived */
-                   {
-                     if (nat_ip4_reass_add_fragment
-                         (thread_index, reass0, bi0, &fragments_to_drop))
-                       {
-                         b0->error =
-                           node->errors[NAT44_CLASSIFY_ERROR_MAX_FRAG];
-                         nat_elog_notice
-                           ("maximum fragments per reassembly exceeded");
-                         next0 = NAT44_CLASSIFY_NEXT_DROP;
-                         goto enqueue0;
-                       }
-                     cached0 = 1;
-                     goto enqueue0;
-                   }
-                 else if (reass0->classify_next ==
-                          NAT_REASS_IP4_CLASSIFY_NEXT_OUT2IN)
+                 m = pool_elt_at_index (sm->static_mappings, value0.value);
+                 if (m->local_addr.as_u32 != m->external_addr.as_u32)
                    next0 = NAT44_CLASSIFY_NEXT_OUT2IN;
-                 else if (reass0->classify_next ==
-                          NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT)
-                   next0 = NAT44_CLASSIFY_NEXT_IN2OUT;
                }
            }
 
@@ -244,65 +158,131 @@ nat44_classify_node_fn_inline (vlib_main_t * vm,
            {
              nat44_classify_trace_t *t =
                vlib_add_trace (vm, node, b0, sizeof (*t));
-             t->cached = cached0;
-             if (!cached0)
-               t->next_in2out = next0 == NAT44_CLASSIFY_NEXT_IN2OUT ? 1 : 0;
+             t->cached = 0;
+             t->next_in2out = next0 == NAT44_CLASSIFY_NEXT_IN2OUT ? 1 : 0;
            }
 
-         if (cached0)
-           {
-             n_left_to_next++;
-             to_next--;
-             frag_cached++;
-           }
-         else
-           {
-             next_in2out += next0 == NAT44_CLASSIFY_NEXT_IN2OUT;
-             next_out2in += next0 == NAT44_CLASSIFY_NEXT_OUT2IN;
+         next_in2out += next0 == NAT44_CLASSIFY_NEXT_IN2OUT;
+         next_out2in += next0 == NAT44_CLASSIFY_NEXT_OUT2IN;
 
-             /* 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);
-           }
+         /* 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, node->node_index,
+                              NAT44_CLASSIFY_ERROR_NEXT_IN2OUT, next_in2out);
+  vlib_node_increment_counter (vm, node->node_index,
+                              NAT44_CLASSIFY_ERROR_NEXT_OUT2IN, next_out2in);
+  return frame->n_vectors;
+}
+
+static inline uword
+nat44_handoff_classify_node_fn_inline (vlib_main_t * vm,
+                                      vlib_node_runtime_t * node,
+                                      vlib_frame_t * frame)
+{
+  u32 n_left_from, *from, *to_next;
+  nat44_classify_next_t next_index;
+  snat_main_t *sm = &snat_main;
+  snat_static_mapping_t *m;
+  u32 next_in2out = 0, next_out2in = 0;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
 
-         if (n_left_from == 0 && vec_len (fragments_to_loopback))
+  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 = NAT_NEXT_IN2OUT_CLASSIFY;
+         ip4_header_t *ip0;
+         snat_address_t *ap;
+         clib_bihash_kv_8_8_t kv0, value0;
+
+         /* 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);
+
+          /* *INDENT-OFF* */
+          vec_foreach (ap, sm->addresses)
+            {
+              if (ip0->dst_address.as_u32 == ap->addr.as_u32)
+                {
+                  next0 = NAT_NEXT_OUT2IN_CLASSIFY;
+                  goto enqueue0;
+                }
+            }
+          /* *INDENT-ON* */
+
+         if (PREDICT_FALSE (pool_elts (sm->static_mappings)))
            {
-             from = vlib_frame_vector_args (frame);
-             u32 len = vec_len (fragments_to_loopback);
-             if (len <= VLIB_FRAME_SIZE)
+             init_nat_k (&kv0, ip0->dst_address, 0, 0, 0);
+             /* try to classify the fragment based on IP header alone */
+             if (!clib_bihash_search_8_8 (&sm->static_mapping_by_external,
+                                          &kv0, &value0))
                {
-                 clib_memcpy_fast (from, fragments_to_loopback,
-                                   sizeof (u32) * len);
-                 n_left_from = len;
-                 vec_reset_length (fragments_to_loopback);
+                 m = pool_elt_at_index (sm->static_mappings, value0.value);
+                 if (m->local_addr.as_u32 != m->external_addr.as_u32)
+                   next0 = NAT_NEXT_OUT2IN_CLASSIFY;
+                 goto enqueue0;
                }
-             else
+             init_nat_k (&kv0, ip0->dst_address,
+                         vnet_buffer (b0)->ip.reass.l4_dst_port, 0,
+                         ip_proto_to_nat_proto (ip0->protocol));
+             if (!clib_bihash_search_8_8
+                 (&sm->static_mapping_by_external, &kv0, &value0))
                {
-                 clib_memcpy_fast (from, fragments_to_loopback +
-                                   (len - VLIB_FRAME_SIZE),
-                                   sizeof (u32) * VLIB_FRAME_SIZE);
-                 n_left_from = VLIB_FRAME_SIZE;
-                 _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
+                 m = pool_elt_at_index (sm->static_mappings, value0.value);
+                 if (m->local_addr.as_u32 != m->external_addr.as_u32)
+                   next0 = NAT_NEXT_OUT2IN_CLASSIFY;
                }
            }
+
+       enqueue0:
+         if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
+                            && (b0->flags & VLIB_BUFFER_IS_TRACED)))
+           {
+             nat44_classify_trace_t *t =
+               vlib_add_trace (vm, node, b0, sizeof (*t));
+             t->cached = 0;
+             t->next_in2out = next0 == NAT_NEXT_IN2OUT_CLASSIFY ? 1 : 0;
+           }
+
+         next_in2out += next0 == NAT_NEXT_IN2OUT_CLASSIFY;
+         next_out2in += next0 == NAT_NEXT_OUT2IN_CLASSIFY;
+
+         /* 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);
     }
 
-  nat_send_all_to_node (vm, fragments_to_drop, node, 0,
-                       NAT44_CLASSIFY_NEXT_DROP);
-
-  vec_free (fragments_to_drop);
-
   vlib_node_increment_counter (vm, node->node_index,
                               NAT44_CLASSIFY_ERROR_NEXT_IN2OUT, next_in2out);
   vlib_node_increment_counter (vm, node->node_index,
                               NAT44_CLASSIFY_ERROR_NEXT_OUT2IN, next_out2in);
-  vlib_node_increment_counter (vm, node->node_index,
-                              NAT44_CLASSIFY_ERROR_FRAG_CACHED, frag_cached);
-
   return frame->n_vectors;
 }
 
@@ -315,12 +295,7 @@ nat44_ed_classify_node_fn_inline (vlib_main_t * vm,
   nat44_classify_next_t next_index;
   snat_main_t *sm = &snat_main;
   snat_static_mapping_t *m;
-  u32 thread_index = vm->thread_index;
-  snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
-  u32 *fragments_to_drop = 0;
-  u32 *fragments_to_loopback = 0;
-  u32 next_in2out = 0, next_out2in = 0, frag_cached = 0;
-  u8 in_loopback = 0;
+  u32 next_in2out = 0, next_out2in = 0;
 
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
@@ -336,16 +311,12 @@ nat44_ed_classify_node_fn_inline (vlib_main_t * vm,
        {
          u32 bi0;
          vlib_buffer_t *b0;
-         u32 next0 =
-           NAT_NEXT_IN2OUT_ED_FAST_PATH, sw_if_index0, rx_fib_index0;
+         u32 next0 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
+         u32 sw_if_index0, rx_fib_index0;
          ip4_header_t *ip0;
          snat_address_t *ap;
-         snat_session_key_t m_key0;
          clib_bihash_kv_8_8_t kv0, value0;
          clib_bihash_kv_16_8_t ed_kv0, ed_value0;
-         udp_header_t *udp0;
-         nat_reass_ip4_t *reass0;
-         u8 cached0 = 0;
 
          /* speculatively enqueue b0 to the current next frame */
          bi0 = from[0];
@@ -357,120 +328,50 @@ nat44_ed_classify_node_fn_inline (vlib_main_t * vm,
 
          b0 = vlib_get_buffer (vm, bi0);
          ip0 = vlib_buffer_get_current (b0);
-         udp0 = ip4_next_header (ip0);
 
-         if (!in_loopback)
-           {
-             u32 arc_next = 0;
-
-             vnet_feature_next (&arc_next, b0);
-             nat_buffer_opaque (b0)->arc_next = arc_next;
-           }
+         u32 arc_next;
+         vnet_feature_next (&arc_next, b0);
+         vnet_buffer2 (b0)->nat.arc_next = arc_next;
 
          if (ip0->protocol != IP_PROTOCOL_ICMP)
            {
-             if (!ip4_is_fragment (ip0) || ip4_is_first_fragment (ip0))
+             /* process leading fragment/whole packet (with L4 header) */
+             sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+             rx_fib_index0 =
+               fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
+                                                    sw_if_index0);
+             init_ed_k (&ed_kv0, ip0->src_address,
+                        vnet_buffer (b0)->ip.reass.l4_src_port,
+                        ip0->dst_address,
+                        vnet_buffer (b0)->ip.reass.l4_dst_port,
+                        rx_fib_index0, ip0->protocol);
+             /* process whole packet */
+             if (!clib_bihash_search_16_8 (&sm->flow_hash, &ed_kv0,
+                                           &ed_value0))
                {
-                 /* process leading fragment/whole packet (with L4 header) */
-                 sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
-                 rx_fib_index0 =
-                   fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
-                                                        sw_if_index0);
-                 make_ed_kv (&ed_kv0, &ip0->src_address,
-                             &ip0->dst_address, ip0->protocol,
-                             rx_fib_index0, udp0->src_port, udp0->dst_port);
-                 if (ip4_is_fragment (ip0))
+                 ASSERT (vm->thread_index ==
+                         ed_value_get_thread_index (&ed_value0));
+                 snat_main_per_thread_data_t *tsm =
+                   &sm->per_thread_data[vm->thread_index];
+                 snat_session_t *s = pool_elt_at_index (
+                   tsm->sessions, ed_value_get_session_index (&ed_value0));
+                 clib_bihash_kv_16_8_t i2o_kv;
+                 nat_6t_flow_to_ed_k (&i2o_kv, &s->i2o);
+                 vnet_buffer2 (b0)->nat.cached_session_index =
+                   ed_value_get_session_index (&ed_value0);
+                 if (i2o_kv.key[0] == ed_kv0.key[0] &&
+                     i2o_kv.key[1] == ed_kv0.key[1])
                    {
-                     reass0 =
-                       nat_ip4_reass_find_or_create (ip0->src_address,
-                                                     ip0->dst_address,
-                                                     ip0->fragment_id,
-                                                     ip0->protocol, 1,
-                                                     &fragments_to_drop);
-                     if (PREDICT_FALSE (!reass0))
-                       {
-                         next0 = NAT_NEXT_DROP;
-                         b0->error =
-                           node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
-                         nat_elog_notice ("maximum reassemblies exceeded");
-                         goto enqueue0;
-                       }
-                     if (!clib_bihash_search_16_8
-                         (&tsm->in2out_ed, &ed_kv0, &ed_value0))
-                       {
-                         /* session exists so classify as IN2OUT,
-                          * save this information for future fragments and set
-                          * past fragments to be looped over and reprocessed */
-                         reass0->sess_index = ed_value0.value;
-                         reass0->classify_next =
-                           NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT;
-                         nat_ip4_reass_get_frags (reass0,
-                                                  &fragments_to_loopback);
-                         goto enqueue0;
-                       }
-                     else
-                       {
-                         /* session doesn't exist so continue in the code,
-                          * save this information for future fragments and set
-                          * past fragments to be looped over and reprocessed */
-                         reass0->flags |=
-                           NAT_REASS_FLAG_CLASSIFY_ED_CONTINUE;
-                         nat_ip4_reass_get_frags (reass0,
-                                                  &fragments_to_loopback);
-                       }
+                     next0 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
                    }
                  else
                    {
-                     /* process whole packet */
-                     if (!clib_bihash_search_16_8
-                         (&tsm->in2out_ed, &ed_kv0, &ed_value0))
-                       goto enqueue0;
-                     /* session doesn't exist so continue in code */
-                   }
-               }
-             else
-               {
-                 /* process non-first fragment */
-                 reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
-                                                        ip0->dst_address,
-                                                        ip0->fragment_id,
-                                                        ip0->protocol,
-                                                        1,
-                                                        &fragments_to_drop);
-                 if (PREDICT_FALSE (!reass0))
-                   {
-                     next0 = NAT_NEXT_DROP;
-                     b0->error =
-                       node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
-                     nat_elog_notice ("maximum reassemblies exceeded");
-                     goto enqueue0;
-                   }
-                 /* check if first fragment has arrived */
-                 if (reass0->classify_next == NAT_REASS_IP4_CLASSIFY_NONE
-                     && !(reass0->flags &
-                          NAT_REASS_FLAG_CLASSIFY_ED_CONTINUE))
-                   {
-                     /* first fragment still hasn't arrived, cache this fragment */
-                     if (nat_ip4_reass_add_fragment
-                         (thread_index, reass0, bi0, &fragments_to_drop))
-                       {
-                         b0->error =
-                           node->errors[NAT44_CLASSIFY_ERROR_MAX_FRAG];
-                         nat_elog_notice
-                           ("maximum fragments per reassembly exceeded");
-                         next0 = NAT_NEXT_DROP;
-                         goto enqueue0;
-                       }
-                     cached0 = 1;
-                     goto enqueue0;
+                     next0 = NAT_NEXT_OUT2IN_ED_FAST_PATH;
                    }
-                 if (reass0->classify_next ==
-                     NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT)
-                   goto enqueue0;
-                 /* flag NAT_REASS_FLAG_CLASSIFY_ED_CONTINUE is set
-                  * so keep the default next0 and continue in code to
-                  * potentially find other classification for this packet */
+
+                 goto enqueue0;
                }
+             /* session doesn't exist so continue in code */
            }
 
           /* *INDENT-OFF* */
@@ -486,11 +387,7 @@ nat44_ed_classify_node_fn_inline (vlib_main_t * vm,
 
          if (PREDICT_FALSE (pool_elts (sm->static_mappings)))
            {
-             m_key0.addr = ip0->dst_address;
-             m_key0.port = 0;
-             m_key0.protocol = 0;
-             m_key0.fib_index = 0;
-             kv0.key = m_key0.as_u64;
+             init_nat_k (&kv0, ip0->dst_address, 0, 0, 0);
              /* try to classify the fragment based on IP header alone */
              if (!clib_bihash_search_8_8 (&sm->static_mapping_by_external,
                                           &kv0, &value0))
@@ -500,85 +397,15 @@ nat44_ed_classify_node_fn_inline (vlib_main_t * vm,
                    next0 = NAT_NEXT_OUT2IN_ED_FAST_PATH;
                  goto enqueue0;
                }
-             if (!ip4_is_fragment (ip0) || ip4_is_first_fragment (ip0))
+             init_nat_k (&kv0, ip0->dst_address,
+                         vnet_buffer (b0)->ip.reass.l4_dst_port, 0,
+                         ip_proto_to_nat_proto (ip0->protocol));
+             if (!clib_bihash_search_8_8
+                 (&sm->static_mapping_by_external, &kv0, &value0))
                {
-                 /* process leading fragment/whole packet (with L4 header) */
-                 m_key0.port = clib_net_to_host_u16 (udp0->dst_port);
-                 m_key0.protocol = ip_proto_to_snat_proto (ip0->protocol);
-                 kv0.key = m_key0.as_u64;
-                 if (!clib_bihash_search_8_8
-                     (&sm->static_mapping_by_external, &kv0, &value0))
-                   {
-                     m =
-                       pool_elt_at_index (sm->static_mappings, value0.value);
-                     if (m->local_addr.as_u32 != m->external_addr.as_u32)
-                       next0 = NAT_NEXT_OUT2IN_ED_FAST_PATH;
-                   }
-                 if (ip4_is_fragment (ip0))
-                   {
-                     reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
-                                                            ip0->dst_address,
-                                                            ip0->fragment_id,
-                                                            ip0->protocol,
-                                                            1,
-                                                            &fragments_to_drop);
-                     if (PREDICT_FALSE (!reass0))
-                       {
-                         next0 = NAT_NEXT_DROP;
-                         b0->error =
-                           node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
-                         nat_elog_notice ("maximum reassemblies exceeded");
-                         goto enqueue0;
-                       }
-                     /* save classification for future fragments and set past
-                      * fragments to be looped over and reprocessed */
-                     if (next0 == NAT_NEXT_OUT2IN_ED_FAST_PATH)
-                       reass0->classify_next = NAT_NEXT_OUT2IN_ED_REASS;
-                     else
-                       reass0->classify_next = NAT_NEXT_IN2OUT_ED_REASS;
-                     nat_ip4_reass_get_frags (reass0,
-                                              &fragments_to_loopback);
-                   }
-               }
-             else
-               {
-                 /* process non-first fragment */
-                 reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
-                                                        ip0->dst_address,
-                                                        ip0->fragment_id,
-                                                        ip0->protocol,
-                                                        1,
-                                                        &fragments_to_drop);
-                 if (PREDICT_FALSE (!reass0))
-                   {
-                     next0 = NAT_NEXT_DROP;
-                     b0->error =
-                       node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
-                     nat_elog_notice ("maximum reassemblies exceeded");
-                     goto enqueue0;
-                   }
-                 if (reass0->classify_next == NAT_REASS_IP4_CLASSIFY_NONE)
-                   /* first fragment still hasn't arrived */
-                   {
-                     if (nat_ip4_reass_add_fragment
-                         (thread_index, reass0, bi0, &fragments_to_drop))
-                       {
-                         b0->error =
-                           node->errors[NAT44_CLASSIFY_ERROR_MAX_FRAG];
-                         nat_elog_notice
-                           ("maximum fragments per reassembly exceeded");
-                         next0 = NAT_NEXT_DROP;
-                         goto enqueue0;
-                       }
-                     cached0 = 1;
-                     goto enqueue0;
-                   }
-                 else if (reass0->classify_next ==
-                          NAT_REASS_IP4_CLASSIFY_NEXT_OUT2IN)
+                 m = pool_elt_at_index (sm->static_mappings, value0.value);
+                 if (m->local_addr.as_u32 != m->external_addr.as_u32)
                    next0 = NAT_NEXT_OUT2IN_ED_FAST_PATH;
-                 else if (reass0->classify_next ==
-                          NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT)
-                   next0 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
                }
            }
 
@@ -588,67 +415,26 @@ nat44_ed_classify_node_fn_inline (vlib_main_t * vm,
            {
              nat44_classify_trace_t *t =
                vlib_add_trace (vm, node, b0, sizeof (*t));
-             t->cached = cached0;
-             if (!cached0)
-               t->next_in2out =
-                 next0 == NAT_NEXT_IN2OUT_ED_FAST_PATH ? 1 : 0;
-           }
-
-         if (cached0)
-           {
-             n_left_to_next++;
-             to_next--;
-             frag_cached++;
+             t->cached = 0;
+             t->next_in2out = next0 == NAT_NEXT_IN2OUT_ED_FAST_PATH ? 1 : 0;
            }
-         else
-           {
-             next_in2out += next0 == NAT_NEXT_IN2OUT_ED_FAST_PATH;
-             next_out2in += next0 == NAT_NEXT_OUT2IN_ED_FAST_PATH;
 
-             /* 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);
-           }
+         next_in2out += next0 == NAT_NEXT_IN2OUT_ED_FAST_PATH;
+         next_out2in += next0 == NAT_NEXT_OUT2IN_ED_FAST_PATH;
 
-         if (n_left_from == 0 && vec_len (fragments_to_loopback))
-           {
-             in_loopback = 1;
-             from = vlib_frame_vector_args (frame);
-             u32 len = vec_len (fragments_to_loopback);
-             if (len <= VLIB_FRAME_SIZE)
-               {
-                 clib_memcpy_fast (from, fragments_to_loopback,
-                                   sizeof (u32) * len);
-                 n_left_from = len;
-                 vec_reset_length (fragments_to_loopback);
-               }
-             else
-               {
-                 clib_memcpy_fast (from, fragments_to_loopback +
-                                   (len - VLIB_FRAME_SIZE),
-                                   sizeof (u32) * VLIB_FRAME_SIZE);
-                 n_left_from = VLIB_FRAME_SIZE;
-                 _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
-               }
-           }
+         /* 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);
     }
 
-  nat_send_all_to_node (vm, fragments_to_drop, node, 0,
-                       NAT44_CLASSIFY_NEXT_DROP);
-
-  vec_free (fragments_to_drop);
-
   vlib_node_increment_counter (vm, node->node_index,
                               NAT44_CLASSIFY_ERROR_NEXT_IN2OUT, next_in2out);
   vlib_node_increment_counter (vm, node->node_index,
                               NAT44_CLASSIFY_ERROR_NEXT_OUT2IN, next_out2in);
-  vlib_node_increment_counter (vm, node->node_index,
-                              NAT44_CLASSIFY_ERROR_FRAG_CACHED, frag_cached);
-
   return frame->n_vectors;
 }
 
@@ -693,47 +479,20 @@ VLIB_REGISTER_NODE (nat44_ed_classify_node) = {
 };
 /* *INDENT-ON* */
 
-VLIB_NODE_FN (nat44_det_classify_node) (vlib_main_t * vm,
-                                       vlib_node_runtime_t * node,
-                                       vlib_frame_t * frame)
-{
-  return nat44_classify_node_fn_inline (vm, node, frame);
-}
-
-/* *INDENT-OFF* */
-VLIB_REGISTER_NODE (nat44_det_classify_node) = {
-  .name = "nat44-det-classify",
-  .vector_size = sizeof (u32),
-  .format_trace = format_nat44_classify_trace,
-  .type = VLIB_NODE_TYPE_INTERNAL,
-  .n_next_nodes = NAT44_CLASSIFY_N_NEXT,
-  .next_nodes = {
-    [NAT44_CLASSIFY_NEXT_IN2OUT] = "nat44-det-in2out",
-    [NAT44_CLASSIFY_NEXT_OUT2IN] = "nat44-det-out2in",
-    [NAT44_CLASSIFY_NEXT_DROP] = "error-drop",
-  },
-};
-/* *INDENT-ON* */
-
 VLIB_NODE_FN (nat44_handoff_classify_node) (vlib_main_t * vm,
                                            vlib_node_runtime_t * node,
                                            vlib_frame_t * frame)
 {
-  return nat44_classify_node_fn_inline (vm, node, frame);
+  return nat44_handoff_classify_node_fn_inline (vm, node, frame);
 }
 
 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (nat44_handoff_classify_node) = {
   .name = "nat44-handoff-classify",
   .vector_size = sizeof (u32),
+  .sibling_of = "nat-default",
   .format_trace = format_nat44_classify_trace,
   .type = VLIB_NODE_TYPE_INTERNAL,
-  .n_next_nodes = NAT44_CLASSIFY_N_NEXT,
-  .next_nodes = {
-    [NAT44_CLASSIFY_NEXT_IN2OUT] = "nat44-in2out-worker-handoff",
-    [NAT44_CLASSIFY_NEXT_OUT2IN] = "nat44-out2in-worker-handoff",
-    [NAT44_CLASSIFY_NEXT_DROP] = "error-drop",
-  },
 };
 
 /* *INDENT-ON* */