nat: fixed input validation
[vpp.git] / src / plugins / nat / out2in_ed.c
index 5b70b0c..5d759fb 100644 (file)
@@ -31,6 +31,7 @@
 #include <nat/nat44/inlines.h>
 #include <nat/nat_syslog.h>
 #include <nat/nat_ha.h>
+#include <nat/nat44/ed_inlines.h>
 
 static char *nat_out2in_ed_error_strings[] = {
 #define _(sym,string) string,
@@ -71,6 +72,8 @@ icmp_out2in_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
                          vlib_node_runtime_t * node, u32 next0, f64 now,
                          u32 thread_index, snat_session_t ** p_s0)
 {
+  vlib_main_t *vm = vlib_get_main ();
+
   next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
                       next0, thread_index, p_s0, 0);
   snat_session_t *s0 = *p_s0;
@@ -79,7 +82,7 @@ icmp_out2in_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
       /* Accounting */
       nat44_session_update_counters (s0, now,
                                     vlib_buffer_length_in_chain
-                                    (sm->vlib_main, b0), thread_index);
+                                    (vm, b0), thread_index);
       /* Per-user LRU list maintenance */
       nat44_session_update_lru (sm, s0, thread_index);
     }
@@ -94,7 +97,10 @@ nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
   nat44_is_idle_session_ctx_t *ctx = arg;
   snat_session_t *s;
   u64 sess_timeout_time;
-  nat_ed_ses_key_t ed_key;
+  u8 proto;
+  u16 r_port, l_port;
+  ip4_address_t *l_addr, *r_addr;
+  u32 fib_index;
   clib_bihash_kv_16_8_t ed_kv;
   int i;
   snat_address_t *a;
@@ -106,41 +112,31 @@ nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
   if (ctx->now >= sess_timeout_time)
     {
-      ed_key.l_addr = s->in2out.addr;
-      ed_key.r_addr = s->ext_host_addr;
-      ed_key.fib_index = s->in2out.fib_index;
+      l_addr = &s->in2out.addr;
+      r_addr = &s->ext_host_addr;
+      fib_index = s->in2out.fib_index;
       if (snat_is_unk_proto_session (s))
        {
-         ed_key.proto = s->in2out.port;
-         ed_key.r_port = 0;
-         ed_key.l_port = 0;
+         proto = s->in2out.port;
+         r_port = 0;
+         l_port = 0;
        }
       else
        {
-         ed_key.proto = snat_proto_to_ip_proto (s->in2out.protocol);
-         ed_key.l_port = s->in2out.port;
-         ed_key.r_port = s->ext_host_port;
+         proto = nat_proto_to_ip_proto (s->in2out.protocol);
+         l_port = s->in2out.port;
+         r_port = s->ext_host_port;
        }
       if (is_twice_nat_session (s))
        {
-         ed_key.r_addr = s->ext_host_nat_addr;
-         ed_key.r_port = s->ext_host_nat_port;
+         r_addr = &s->ext_host_nat_addr;
+         r_port = s->ext_host_nat_port;
        }
-      ed_kv.key[0] = ed_key.as_u64[0];
-      ed_kv.key[1] = ed_key.as_u64[1];
+      make_ed_kv (l_addr, r_addr, proto, fib_index, l_port, r_port, ~0, ~0,
+                 &ed_kv);
       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &ed_kv, 0))
        nat_elog_warn ("in2out_ed key del failed");
 
-      ed_bihash_kv_t bihash_key;
-      clib_memset (&bihash_key, 0, sizeof (bihash_key));
-      bihash_key.k.dst_address = s->ext_host_addr.as_u32;
-      bihash_key.k.dst_port = s->ext_host_port;
-      bihash_key.k.src_address = s->out2in.addr.as_u32;
-      bihash_key.k.src_port = s->out2in.port;
-      bihash_key.k.protocol = s->out2in.protocol;
-      clib_bihash_add_del_16_8 (&sm->ed_ext_ports, &bihash_key.kv,
-                               0 /* is_add */ );
-
       if (snat_is_unk_proto_session (s))
        goto delete;
 
@@ -186,7 +182,7 @@ nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
                                          &s->out2in);
     delete:
-      nat44_delete_session (sm, s, ctx->thread_index);
+      nat_ed_session_delete (sm, s, ctx->thread_index, 1);
       return 1;
     }
 
@@ -200,12 +196,12 @@ create_session_for_static_mapping_ed (snat_main_t * sm,
                                      snat_session_key_t l_key,
                                      snat_session_key_t e_key,
                                      vlib_node_runtime_t * node,
+                                     u32 rx_fib_index,
                                      u32 thread_index,
                                      twice_nat_type_t twice_nat,
                                      lb_nat_type_t lb_nat, f64 now)
 {
   snat_session_t *s;
-  snat_user_t *u;
   ip4_header_t *ip;
   udp_header_t *udp;
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
@@ -213,26 +209,18 @@ create_session_for_static_mapping_ed (snat_main_t * sm,
   snat_session_key_t eh_key;
   nat44_is_idle_session_ctx_t ctx;
 
-  if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
+  if (PREDICT_FALSE
+      (nat44_ed_maximum_sessions_exceeded (sm, rx_fib_index, thread_index)))
     {
       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
       nat_elog_notice ("maximum sessions exceeded");
       return 0;
     }
 
-  u = nat_user_get_or_create (sm, &l_key.addr, l_key.fib_index, thread_index);
-  if (!u)
-    {
-      b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
-      nat_elog_warn ("create NAT user failed");
-      return 0;
-    }
-
-  s = nat_ed_session_alloc (sm, u, thread_index, now);
+  s = nat_ed_session_alloc (sm, thread_index, now, e_key.protocol);
   if (!s)
     {
       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_USER_SESS_EXCEEDED];
-      nat44_delete_user_with_no_session (sm, u, thread_index);
       nat_elog_warn ("create NAT session failed");
       return 0;
     }
@@ -241,7 +229,7 @@ create_session_for_static_mapping_ed (snat_main_t * sm,
   udp = ip4_next_header (ip);
 
   s->ext_host_addr.as_u32 = ip->src_address.as_u32;
-  s->ext_host_port = e_key.protocol == SNAT_PROTOCOL_ICMP ? 0 : udp->src_port;
+  s->ext_host_port = e_key.protocol == NAT_PROTOCOL_ICMP ? 0 : udp->src_port;
   s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
   if (lb_nat)
     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
@@ -251,15 +239,14 @@ create_session_for_static_mapping_ed (snat_main_t * sm,
   s->out2in = e_key;
   s->in2out = l_key;
   s->in2out.protocol = s->out2in.protocol;
-  user_session_increment (sm, u, 1);
 
   /* Add to lookup tables */
-  make_ed_kv (&kv, &e_key.addr, &s->ext_host_addr, ip->protocol,
-             e_key.fib_index, e_key.port, s->ext_host_port);
-  kv.value = s - tsm->sessions;
+  make_ed_kv (&e_key.addr, &s->ext_host_addr, ip->protocol,
+             e_key.fib_index, e_key.port, s->ext_host_port, thread_index,
+             s - tsm->sessions, &kv);
   ctx.now = now;
   ctx.thread_index = thread_index;
-  if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->out2in_ed, &kv,
+  if (clib_bihash_add_or_overwrite_stale_16_8 (&sm->out2in_ed, &kv,
                                               nat44_o2i_ed_is_idle_session_cb,
                                               &ctx))
     nat_elog_notice ("out2in-ed key add failed");
@@ -274,23 +261,24 @@ create_session_for_static_mapping_ed (snat_main_t * sm,
                                               tsm->snat_thread_index))
        {
          b->error = node->errors[NAT_OUT2IN_ED_ERROR_OUT_OF_PORTS];
-         nat44_delete_session (sm, s, thread_index);
-         if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &kv, 0))
+         nat_ed_session_delete (sm, s, thread_index, 1);
+         if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &kv, 0))
            nat_elog_notice ("out2in-ed key del failed");
          return 0;
        }
       s->ext_host_nat_addr.as_u32 = eh_key.addr.as_u32;
       s->ext_host_nat_port = eh_key.port;
       s->flags |= SNAT_SESSION_FLAG_TWICE_NAT;
-      make_ed_kv (&kv, &l_key.addr, &s->ext_host_nat_addr, ip->protocol,
-                 l_key.fib_index, l_key.port, s->ext_host_nat_port);
+      make_ed_kv (&l_key.addr, &s->ext_host_nat_addr, ip->protocol,
+                 l_key.fib_index, l_key.port, s->ext_host_nat_port,
+                 thread_index, s - tsm->sessions, &kv);
     }
   else
     {
-      make_ed_kv (&kv, &l_key.addr, &s->ext_host_addr, ip->protocol,
-                 l_key.fib_index, l_key.port, s->ext_host_port);
+      make_ed_kv (&l_key.addr, &s->ext_host_addr, ip->protocol,
+                 l_key.fib_index, l_key.port, s->ext_host_port, thread_index,
+                 s - tsm->sessions, &kv);
     }
-  kv.value = s - tsm->sessions;
   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, &kv,
                                               nat44_i2o_ed_is_idle_session_cb,
                                               &ctx))
@@ -320,14 +308,14 @@ create_session_for_static_mapping_ed (snat_main_t * sm,
 }
 
 static int
-next_src_nat (snat_main_t * sm, ip4_header_t * ip, u8 proto, u16 src_port,
+next_src_nat (snat_main_t * sm, ip4_header_t * ip, u16 src_port,
              u16 dst_port, u32 thread_index, u32 rx_fib_index)
 {
   clib_bihash_kv_16_8_t kv, value;
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 
-  make_ed_kv (&kv, &ip->src_address, &ip->dst_address, proto,
-             rx_fib_index, src_port, dst_port);
+  make_ed_kv (&ip->src_address, &ip->dst_address, ip->protocol,
+             rx_fib_index, src_port, dst_port, ~0, ~0, &kv);
   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
     return 1;
 
@@ -338,82 +326,75 @@ static void
 create_bypass_for_fwd (snat_main_t * sm, vlib_buffer_t * b, ip4_header_t * ip,
                       u32 rx_fib_index, u32 thread_index)
 {
-  nat_ed_ses_key_t key;
   clib_bihash_kv_16_8_t kv, value;
   udp_header_t *udp;
-  snat_user_t *u;
   snat_session_t *s = 0;
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
-  f64 now = vlib_time_now (sm->vlib_main);
+  vlib_main_t *vm = vlib_get_main ();
+  f64 now = vlib_time_now (vm);
+  u16 l_port, r_port;
 
   if (ip->protocol == IP_PROTOCOL_ICMP)
     {
-      if (get_icmp_o2i_ed_key (b, ip, &key))
+      if (get_icmp_o2i_ed_key
+         (b, ip, rx_fib_index, ~0, ~0, 0, &l_port, &r_port, &kv))
        return;
     }
-  else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
-    {
-      udp = ip4_next_header (ip);
-      key.r_addr = ip->src_address;
-      key.l_addr = ip->dst_address;
-      key.proto = ip->protocol;
-      key.l_port = udp->dst_port;
-      key.r_port = udp->src_port;
-    }
   else
     {
-      key.r_addr = ip->src_address;
-      key.l_addr = ip->dst_address;
-      key.proto = ip->protocol;
-      key.l_port = key.r_port = 0;
+      if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
+       {
+         udp = ip4_next_header (ip);
+         l_port = udp->dst_port;
+         r_port = udp->src_port;
+       }
+      else
+       {
+         l_port = 0;
+         r_port = 0;
+       }
+      make_ed_kv (&ip->dst_address, &ip->src_address, ip->protocol,
+                 rx_fib_index, l_port, r_port, ~0, ~0, &kv);
     }
-  key.fib_index = 0;
-  kv.key[0] = key.as_u64[0];
-  kv.key[1] = key.as_u64[1];
 
   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
     {
-      s = pool_elt_at_index (tsm->sessions, value.value);
+      ASSERT (thread_index == ed_value_get_thread_index (&value));
+      s =
+       pool_elt_at_index (tsm->sessions,
+                          ed_value_get_session_index (&value));
     }
   else
     {
       u32 proto;
 
-      if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
+      if (PREDICT_FALSE
+         (nat44_ed_maximum_sessions_exceeded
+          (sm, rx_fib_index, thread_index)))
        return;
 
-      u = nat_user_get_or_create (sm, &ip->dst_address, sm->inside_fib_index,
-                                 thread_index);
-      if (!u)
-       {
-         nat_elog_warn ("create NAT user failed");
-         return;
-       }
-
-      s = nat_ed_session_alloc (sm, u, thread_index, now);
+      s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol);
       if (!s)
        {
-         nat44_delete_user_with_no_session (sm, u, thread_index);
          nat_elog_warn ("create NAT session failed");
          return;
        }
 
-      proto = ip_proto_to_snat_proto (key.proto);
+      proto = ip_proto_to_nat_proto (ip->protocol);
 
-      s->ext_host_addr = key.r_addr;
-      s->ext_host_port = key.r_port;
+      s->ext_host_addr = ip->src_address;
+      s->ext_host_port = r_port;
       s->flags |= SNAT_SESSION_FLAG_FWD_BYPASS;
-      s->out2in.addr = key.l_addr;
-      s->out2in.port = key.l_port;
+      s->out2in.addr = ip->dst_address;
+      s->out2in.port = l_port;
       s->out2in.protocol = proto;
-      if (proto == ~0)
+      if (proto == NAT_PROTOCOL_OTHER)
        {
          s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
          s->out2in.port = ip->protocol;
        }
       s->out2in.fib_index = 0;
       s->in2out = s->out2in;
-      user_session_increment (sm, u, 0);
 
       kv.value = s - tsm->sessions;
       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &kv, 1))
@@ -455,32 +436,31 @@ icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
                      u8 * p_dont_translate, void *d, void *e)
 {
   u32 next = ~0, sw_if_index, rx_fib_index;
-  nat_ed_ses_key_t key;
   clib_bihash_kv_16_8_t kv, value;
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
   snat_session_t *s = 0;
   u8 dont_translate = 0, is_addr_only, identity_nat;
   snat_session_key_t e_key, l_key;
+  u16 l_port, r_port;
+  vlib_main_t *vm = vlib_get_main ();
 
   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 
-  if (get_icmp_o2i_ed_key (b, ip, &key))
+  if (get_icmp_o2i_ed_key
+      (b, ip, rx_fib_index, ~0, ~0, p_proto, &l_port, &r_port, &kv))
     {
       b->error = node->errors[NAT_OUT2IN_ED_ERROR_UNSUPPORTED_PROTOCOL];
       next = NAT_NEXT_DROP;
       goto out;
     }
-  key.fib_index = rx_fib_index;
-  kv.key[0] = key.as_u64[0];
-  kv.key[1] = key.as_u64[1];
 
-  if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
+  if (clib_bihash_search_16_8 (&sm->out2in_ed, &kv, &value))
     {
       /* Try to match static mapping */
       e_key.addr = ip->dst_address;
-      e_key.port = key.l_port;
-      e_key.protocol = ip_proto_to_snat_proto (key.proto);
+      e_key.port = l_port;
+      e_key.protocol = ip_proto_to_nat_proto (ip->protocol);
       e_key.fib_index = rx_fib_index;
       if (snat_static_mapping_match
          (sm, e_key, &l_key, 1, &is_addr_only, 0, 0, 0, &identity_nat))
@@ -501,7 +481,7 @@ icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
          else
            {
              dont_translate = 1;
-             if (next_src_nat (sm, ip, key.proto, key.l_port, key.r_port,
+             if (next_src_nat (sm, ip, l_port, r_port,
                                thread_index, rx_fib_index))
                {
                  next = NAT_NEXT_IN2OUT_ED_FAST_PATH;
@@ -534,9 +514,8 @@ icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 
       /* Create session initiated by host from external network */
       s = create_session_for_static_mapping_ed (sm, b, l_key, e_key, node,
-                                               thread_index, 0, 0,
-                                               vlib_time_now
-                                               (sm->vlib_main));
+                                               rx_fib_index, thread_index, 0,
+                                               0, vlib_time_now (vm));
 
       if (!s)
        {
@@ -559,10 +538,11 @@ icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
          goto out;
        }
 
-      s = pool_elt_at_index (tsm->sessions, value.value);
+      ASSERT (thread_index == ed_value_get_thread_index (&value));
+      s =
+       pool_elt_at_index (tsm->sessions,
+                          ed_value_get_session_index (&value));
     }
-
-  *p_proto = ip_proto_to_snat_proto (key.proto);
 out:
   if (s)
     *p_value = s->in2out;
@@ -589,21 +569,25 @@ nat44_ed_out2in_unknown_proto (snat_main_t * sm,
   ip_csum_t sum;
   snat_session_t *s;
   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
-  snat_user_t *u;
 
   old_addr = ip->dst_address.as_u32;
 
-  make_ed_kv (&s_kv, &ip->dst_address, &ip->src_address, ip->protocol,
-             rx_fib_index, 0, 0);
+  make_ed_kv (&ip->dst_address, &ip->src_address, ip->protocol, rx_fib_index,
+             0, 0, ~0, ~0, &s_kv);
 
-  if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &s_kv, &s_value))
+  if (!clib_bihash_search_16_8 (&sm->out2in_ed, &s_kv, &s_value))
     {
-      s = pool_elt_at_index (tsm->sessions, s_value.value);
+      ASSERT (thread_index == ed_value_get_thread_index (&s_value));
+      s =
+       pool_elt_at_index (tsm->sessions,
+                          ed_value_get_session_index (&s_value));
       new_addr = ip->dst_address.as_u32 = s->in2out.addr.as_u32;
     }
   else
     {
-      if (PREDICT_FALSE (nat44_maximum_sessions_exceeded (sm, thread_index)))
+      if (PREDICT_FALSE
+         (nat44_ed_maximum_sessions_exceeded
+          (sm, rx_fib_index, thread_index)))
        {
          b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
          nat_elog_notice ("maximum sessions exceeded");
@@ -622,21 +606,11 @@ nat44_ed_out2in_unknown_proto (snat_main_t * sm,
 
       new_addr = ip->dst_address.as_u32 = m->local_addr.as_u32;
 
-      u = nat_user_get_or_create (sm, &m->local_addr, m->fib_index,
-                                 thread_index);
-      if (!u)
-       {
-         b->error = node->errors[NAT_OUT2IN_ED_ERROR_CANNOT_CREATE_USER];
-         nat_elog_warn ("create NAT user failed");
-         return 0;
-       }
-
       /* Create a new session */
-      s = nat_ed_session_alloc (sm, u, thread_index, now);
+      s = nat_ed_session_alloc (sm, thread_index, now, ip->protocol);
       if (!s)
        {
          b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_USER_SESS_EXCEEDED];
-         nat44_delete_user_with_no_session (sm, u, thread_index);
          nat_elog_warn ("create NAT session failed");
          return 0;
        }
@@ -650,16 +624,14 @@ nat44_ed_out2in_unknown_proto (snat_main_t * sm,
       s->in2out.addr.as_u32 = new_addr;
       s->in2out.fib_index = m->fib_index;
       s->in2out.port = s->out2in.port = ip->protocol;
-      user_session_increment (sm, u, 1);
 
       /* Add to lookup tables */
       s_kv.value = s - tsm->sessions;
-      if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &s_kv, 1))
+      if (clib_bihash_add_del_16_8 (&sm->out2in_ed, &s_kv, 1))
        nat_elog_notice ("out2in key add failed");
 
-      make_ed_kv (&s_kv, &ip->dst_address, &ip->src_address, ip->protocol,
-                 m->fib_index, 0, 0);
-      s_kv.value = s - tsm->sessions;
+      make_ed_kv (&ip->dst_address, &ip->src_address, ip->protocol,
+                 m->fib_index, 0, 0, thread_index, s - tsm->sessions, &s_kv);
       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
        nat_elog_notice ("in2out key add failed");
     }
@@ -683,7 +655,8 @@ nat44_ed_out2in_unknown_proto (snat_main_t * sm,
 static inline uword
 nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
                                          vlib_node_runtime_t * node,
-                                         vlib_frame_t * frame)
+                                         vlib_frame_t * frame,
+                                         int is_multi_worker)
 {
   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
   nat_next_t next_index;
@@ -729,7 +702,7 @@ nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
          n_left_to_next -= 1;
 
          b0 = vlib_get_buffer (vm, bi0);
-         next0 = nat_buffer_opaque (b0)->arc_next;
+         next0 = vnet_buffer2 (b0)->nat.arc_next;
 
          vnet_buffer (b0)->snat.flags = 0;
          ip0 = vlib_buffer_get_current (b0);
@@ -751,35 +724,65 @@ nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
 
          udp0 = ip4_next_header (ip0);
          tcp0 = (tcp_header_t *) udp0;
-         proto0 = ip_proto_to_snat_proto (ip0->protocol);
+         proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-         if (PREDICT_FALSE (proto0 == ~0))
+         if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
            {
              next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
              goto trace0;
            }
 
-         if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+         if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
            {
              next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
              goto trace0;
            }
 
-         make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
+         make_ed_kv (&ip0->dst_address, &ip0->src_address,
                      ip0->protocol, rx_fib_index0,
                      vnet_buffer (b0)->ip.reass.l4_dst_port,
-                     vnet_buffer (b0)->ip.reass.l4_src_port);
+                     vnet_buffer (b0)->ip.reass.l4_src_port, ~0, ~0, &kv0);
+
+         /* there is a stashed index in vnet_buffer2 from handoff node,
+          * see if we can use it */
+         if (is_multi_worker && PREDICT_TRUE
+             (!pool_is_free_index
+              (tsm->sessions,
+               vnet_buffer2 (b0)->nat.ed_out2in_nat_session_index)))
+           {
+             s0 = pool_elt_at_index (tsm->sessions,
+                                     vnet_buffer2 (b0)->
+                                     nat.ed_out2in_nat_session_index);
+             if (PREDICT_TRUE
+                 (s0->out2in.addr.as_u32 == ip0->dst_address.as_u32
+                  && s0->out2in.port ==
+                  vnet_buffer (b0)->ip.reass.l4_dst_port
+                  && s0->out2in.protocol ==
+                  ip_proto_to_nat_proto (ip0->protocol)
+                  && s0->out2in.fib_index == rx_fib_index0
+                  && s0->ext_host_addr.as_u32 == ip0->src_address.as_u32
+                  && s0->ext_host_port ==
+                  vnet_buffer (b0)->ip.reass.l4_src_port))
+               {
+                 /* yes, this is the droid we're looking for */
+                 goto skip_lookup;
+               }
+           }
 
-         if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv0, &value0))
+         if (clib_bihash_search_16_8 (&sm->out2in_ed, &kv0, &value0))
            {
              next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
              goto trace0;
            }
-         s0 = pool_elt_at_index (tsm->sessions, value0.value);
+         ASSERT (thread_index == ed_value_get_thread_index (&value0));
+         s0 =
+           pool_elt_at_index (tsm->sessions,
+                              ed_value_get_session_index (&value0));
 
-         if (s0->tcp_close_timestamp)
+       skip_lookup:
+         if (s0->tcp_closed_timestamp)
            {
-             if (now >= s0->tcp_close_timestamp)
+             if (now >= s0->tcp_closed_timestamp)
                {
                  // session is closed, go slow path
                  next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
@@ -801,7 +804,7 @@ nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
            {
              // session is closed, go slow path
              nat_free_session_data (sm, s0, thread_index, 0);
-             nat44_delete_session (sm, s0, thread_index);
+             nat_ed_session_delete (sm, s0, thread_index, 1);
              next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
              goto trace0;
            }
@@ -822,7 +825,7 @@ nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
 
          old_port0 = vnet_buffer (b0)->ip.reass.l4_dst_port;
 
-         if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+         if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
            {
              if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
                {
@@ -920,7 +923,7 @@ nat44_ed_out2in_fast_path_node_fn_inline (vlib_main_t * vm,
                t->session_index = ~0;
            }
 
-         pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
+         pkts_processed += next0 == vnet_buffer2 (b0)->nat.arc_next;
          /* verify speculative enqueue, maybe switch current next frame */
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
                                           to_next, n_left_to_next,
@@ -1002,7 +1005,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
          n_left_to_next -= 1;
 
          b0 = vlib_get_buffer (vm, bi0);
-         next0 = nat_buffer_opaque (b0)->arc_next;
+         next0 = vnet_buffer2 (b0)->nat.arc_next;
 
          vnet_buffer (b0)->snat.flags = 0;
          ip0 = vlib_buffer_get_current (b0);
@@ -1025,9 +1028,9 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
          udp0 = ip4_next_header (ip0);
          tcp0 = (tcp_header_t *) udp0;
          icmp0 = (icmp46_header_t *) udp0;
-         proto0 = ip_proto_to_snat_proto (ip0->protocol);
+         proto0 = ip_proto_to_nat_proto (ip0->protocol);
 
-         if (PREDICT_FALSE (proto0 == ~0))
+         if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_OTHER))
            {
              s0 =
                nat44_ed_out2in_unknown_proto (sm, b0, ip0, rx_fib_index0,
@@ -1041,7 +1044,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
              goto trace0;
            }
 
-         if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+         if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_ICMP))
            {
              next0 = icmp_out2in_ed_slow_path
                (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
@@ -1050,20 +1053,23 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
              goto trace0;
            }
 
-         make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
+         make_ed_kv (&ip0->dst_address, &ip0->src_address,
                      ip0->protocol, rx_fib_index0,
                      vnet_buffer (b0)->ip.reass.l4_dst_port,
-                     vnet_buffer (b0)->ip.reass.l4_src_port);
+                     vnet_buffer (b0)->ip.reass.l4_src_port, ~0, ~0, &kv0);
 
          s0 = NULL;
-         if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &kv0, &value0))
+         if (!clib_bihash_search_16_8 (&sm->out2in_ed, &kv0, &value0))
            {
-             s0 = pool_elt_at_index (tsm->sessions, value0.value);
+             ASSERT (thread_index == ed_value_get_thread_index (&value0));
+             s0 =
+               pool_elt_at_index (tsm->sessions,
+                                  ed_value_get_session_index (&value0));
 
-             if (s0->tcp_close_timestamp && now >= s0->tcp_close_timestamp)
+             if (s0->tcp_closed_timestamp && now >= s0->tcp_closed_timestamp)
                {
                  nat_free_session_data (sm, s0, thread_index, 0);
-                 nat44_delete_session (sm, s0, thread_index);
+                 nat_ed_session_delete (sm, s0, thread_index, 1);
                  s0 = NULL;
                }
            }
@@ -1086,7 +1092,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
                   * Send DHCP packets to the ipv4 stack, or we won't
                   * be able to use dhcp client on the outside interface
                   */
-                 if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
+                 if (PREDICT_FALSE (proto0 == NAT_PROTOCOL_UDP
                                     && (vnet_buffer (b0)->ip.
                                         reass.l4_dst_port ==
                                         clib_host_to_net_u16
@@ -1103,12 +1109,10 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
                    }
                  else
                    {
-                     if (next_src_nat (sm, ip0, ip0->protocol,
-                                       vnet_buffer (b0)->ip.
-                                       reass.l4_src_port,
-                                       vnet_buffer (b0)->ip.
-                                       reass.l4_dst_port, thread_index,
-                                       rx_fib_index0))
+                     if (next_src_nat
+                         (sm, ip0, vnet_buffer (b0)->ip.reass.l4_src_port,
+                          vnet_buffer (b0)->ip.reass.l4_dst_port,
+                          thread_index, rx_fib_index0))
                        {
                          next0 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
                          goto trace0;
@@ -1126,7 +1130,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
              if (PREDICT_FALSE (identity_nat0))
                goto trace0;
 
-             if ((proto0 == SNAT_PROTOCOL_TCP)
+             if ((proto0 == NAT_PROTOCOL_TCP)
                  && !tcp_flags_is_init (vnet_buffer (b0)->ip.
                                         reass.icmp_type_or_tcp_flags))
                {
@@ -1138,6 +1142,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
              /* Create session initiated by host from external network */
              s0 = create_session_for_static_mapping_ed (sm, b0, l_key0,
                                                         e_key0, node,
+                                                        rx_fib_index0,
                                                         thread_index,
                                                         twice_nat0,
                                                         lb_nat0, now);
@@ -1163,7 +1168,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
 
          old_port0 = vnet_buffer (b0)->ip.reass.l4_dst_port;
 
-         if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+         if (PREDICT_TRUE (proto0 == NAT_PROTOCOL_TCP))
            {
              if (!vnet_buffer (b0)->ip.reass.is_non_first_fragment)
                {
@@ -1261,7 +1266,7 @@ nat44_ed_out2in_slow_path_node_fn_inline (vlib_main_t * vm,
                t->session_index = ~0;
            }
 
-         pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
+         pkts_processed += next0 == vnet_buffer2 (b0)->nat.arc_next;
          /* verify speculative enqueue, maybe switch current next frame */
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
                                           to_next, n_left_to_next,
@@ -1293,7 +1298,14 @@ VLIB_NODE_FN (nat44_ed_out2in_node) (vlib_main_t * vm,
                                     vlib_node_runtime_t * node,
                                     vlib_frame_t * frame)
 {
-  return nat44_ed_out2in_fast_path_node_fn_inline (vm, node, frame);
+  if (snat_main.num_workers > 1)
+    {
+      return nat44_ed_out2in_fast_path_node_fn_inline (vm, node, frame, 1);
+    }
+  else
+    {
+      return nat44_ed_out2in_fast_path_node_fn_inline (vm, node, frame, 0);
+    }
 }
 
 /* *INDENT-OFF* */
@@ -1335,7 +1347,8 @@ format_nat_pre_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 *);
   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
-  return format (s, "out2in next_index %d", t->next_index);
+  return format (s, "out2in next_index %d arc_next_index %d", t->next_index,
+                t->arc_next_index);
 }
 
 VLIB_NODE_FN (nat_pre_out2in_node) (vlib_main_t * vm,