nat: remove nat44-ed relation between SM and addr
[vpp.git] / src / plugins / nat / nat44-ed / nat44_ed.c
index d639392..d3ef3d5 100644 (file)
@@ -179,8 +179,17 @@ VLIB_PLUGIN_REGISTER () = {
 };
 
 static void nat44_ed_db_init (u32 translations, u32 translation_buckets);
-
-static void nat44_ed_db_free ();
+static void nat44_ed_worker_db_free (snat_main_per_thread_data_t *tsm);
+
+static int nat44_ed_add_static_mapping_internal (
+  ip4_address_t l_addr, ip4_address_t e_addr, u16 l_port, u16 e_port,
+  ip_protocol_t proto, u32 vrf_id, u32 sw_if_index, u32 flags,
+  ip4_address_t pool_addr, u8 *tag);
+static int nat44_ed_del_static_mapping_internal (ip4_address_t l_addr,
+                                                ip4_address_t e_addr,
+                                                u16 l_port, u16 e_port,
+                                                ip_protocol_t proto,
+                                                u32 vrf_id, u32 flags);
 
 u32 nat_calc_bihash_buckets (u32 n_elts);
 
@@ -283,60 +292,197 @@ nat44_ed_free_session_data (snat_main_t *sm, snat_session_t *s,
     }
 }
 
+static ip_interface_address_t *
+nat44_ed_get_ip_interface_address (u32 sw_if_index, ip4_address_t addr)
+{
+  snat_main_t *sm = &snat_main;
+
+  ip_lookup_main_t *lm = &sm->ip4_main->lookup_main;
+  ip_interface_address_t *ia;
+  ip4_address_t *ip4a;
+
+  foreach_ip_interface_address (
+    lm, ia, sw_if_index, 1, ({
+      ip4a = ip_interface_address_get_address (lm, ia);
+      nat_log_debug ("sw_if_idx: %u addr: %U ? %U", sw_if_index,
+                    format_ip4_address, ip4a, format_ip4_address, &addr);
+      if (ip4a->as_u32 == addr.as_u32)
+       {
+         return ia;
+       }
+    }));
+  return NULL;
+}
+
 static int
-is_snat_address_used_in_static_mapping (snat_main_t *sm, ip4_address_t addr)
+nat44_ed_resolve_nat_addr_len (snat_address_t *ap,
+                              snat_interface_t *interfaces)
 {
-  snat_static_mapping_t *m;
-  pool_foreach (m, sm->static_mappings)
+  ip_interface_address_t *ia;
+  snat_interface_t *i;
+  u32 fib_index;
+
+  pool_foreach (i, interfaces)
     {
-      if (is_sm_addr_only (m->flags) || is_sm_out2in_only (m->flags) ||
-         is_sm_identity_nat (m->flags))
+      if (!nat44_ed_is_interface_outside (i))
        {
          continue;
        }
-      if (m->external_addr.as_u32 == addr.as_u32)
+
+      fib_index = ip4_fib_table_get_index_for_sw_if_index (i->sw_if_index);
+      if (fib_index != ap->fib_index)
        {
-         return 1;
+         continue;
+       }
+
+      if ((ia = nat44_ed_get_ip_interface_address (i->sw_if_index, ap->addr)))
+       {
+         ap->addr_len = ia->address_length;
+         ap->sw_if_index = i->sw_if_index;
+         ap->net.as_u32 = (ap->addr.as_u32 >> (32 - ap->addr_len))
+                          << (32 - ap->addr_len);
+
+         nat_log_debug ("pool addr %U binds to -> sw_if_idx: %u net: %U/%u",
+                        format_ip4_address, &ap->addr, ap->sw_if_index,
+                        format_ip4_address, &ap->net, ap->addr_len);
+         return 0;
+       }
+    }
+  return 1;
+}
+
+static void
+nat44_ed_update_outside_if_addresses (snat_address_t *ap)
+{
+  snat_main_t *sm = &snat_main;
+
+  if (!nat44_ed_resolve_nat_addr_len (ap, sm->interfaces))
+    {
+      return;
+    }
+
+  if (!nat44_ed_resolve_nat_addr_len (ap, sm->output_feature_interfaces))
+    {
+      return;
+    }
+}
+
+static void
+nat44_ed_bind_if_addr_to_nat_addr (u32 sw_if_index)
+{
+  snat_main_t *sm = &snat_main;
+  ip_interface_address_t *ia;
+  snat_address_t *ap;
+
+  u32 fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
+
+  vec_foreach (ap, sm->addresses)
+    {
+      if (fib_index != ap->fib_index)
+       {
+         continue;
+       }
+
+      if ((ia = nat44_ed_get_ip_interface_address (sw_if_index, ap->addr)))
+       {
+         ap->addr_len = ia->address_length;
+         ap->sw_if_index = sw_if_index;
+         ap->net.as_u32 = (ap->addr.as_u32 >> (32 - ap->addr_len))
+                          << (32 - ap->addr_len);
+
+         nat_log_debug ("pool addr %U binds to -> sw_if_idx: %u net: %U/%u",
+                        format_ip4_address, &ap->addr, ap->sw_if_index,
+                        format_ip4_address, &ap->net, ap->addr_len);
+         return;
        }
     }
-  return 0;
+}
+
+static_always_inline snat_fib_entry_reg_t *
+nat44_ed_get_fib_entry_reg (ip4_address_t addr, u32 sw_if_index, int *out_idx)
+{
+  snat_main_t *sm = &snat_main;
+  snat_fib_entry_reg_t *fe;
+  int i;
+
+  for (i = 0; i < vec_len (sm->fib_entry_reg); i++)
+    {
+      fe = sm->fib_entry_reg + i;
+      if ((addr.as_u32 == fe->addr.as_u32) && (sw_if_index == fe->sw_if_index))
+       {
+         if (out_idx)
+           {
+             *out_idx = i;
+           }
+         return fe;
+       }
+    }
+  return NULL;
 }
 
 static void
-nat44_ed_add_del_addr_to_fib (ip4_address_t *addr, u8 p_len, u32 sw_if_index,
-                             int is_add)
+nat44_ed_add_fib_entry_reg (ip4_address_t addr, u32 sw_if_index)
 {
   // Add the external NAT address to the FIB as receive entries. This ensures
   // that VPP will reply to ARP for this address and we don't need to enable
   // proxy ARP on the outside interface.
-
   snat_main_t *sm = &snat_main;
-  fib_prefix_t prefix = {
-    .fp_len = p_len,
-    .fp_proto = FIB_PROTOCOL_IP4,
-    .fp_addr = {
-               .ip4.as_u32 = addr->as_u32,
-               },
-  };
-  u32 fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
+  snat_fib_entry_reg_t *fe;
 
-  if (is_add)
+  if (!(fe = nat44_ed_get_fib_entry_reg (addr, sw_if_index, 0)))
     {
+      fib_prefix_t prefix = {
+        .fp_len = 32,
+        .fp_proto = FIB_PROTOCOL_IP4,
+        .fp_addr = {
+                 .ip4.as_u32 = addr.as_u32,
+               },
+      };
+      u32 fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
       fib_table_entry_update_one_path (fib_index, &prefix, sm->fib_src_low,
                                       (FIB_ENTRY_FLAG_CONNECTED |
                                        FIB_ENTRY_FLAG_LOCAL |
                                        FIB_ENTRY_FLAG_EXCLUSIVE),
                                       DPO_PROTO_IP4, NULL, sw_if_index, ~0, 1,
                                       NULL, FIB_ROUTE_PATH_FLAG_NONE);
+
+      vec_add2 (sm->fib_entry_reg, fe, 1);
+      clib_memset (fe, 0, sizeof (*fe));
+      fe->addr.as_u32 = addr.as_u32;
+      fe->sw_if_index = sw_if_index;
     }
-  else
+  fe->count++;
+}
+
+static void
+nat44_ed_del_fib_entry_reg (ip4_address_t addr, u32 sw_if_index)
+{
+  snat_main_t *sm = &snat_main;
+  snat_fib_entry_reg_t *fe;
+  int i;
+
+  if ((fe = nat44_ed_get_fib_entry_reg (addr, sw_if_index, &i)))
     {
-      fib_table_entry_delete (fib_index, &prefix, sm->fib_src_low);
+      fe->count--;
+      if (0 == fe->count)
+       {
+         fib_prefix_t prefix = {
+            .fp_len = 32,
+            .fp_proto = FIB_PROTOCOL_IP4,
+            .fp_addr = {
+              .ip4.as_u32 = addr.as_u32,
+                   },
+          };
+         u32 fib_index =
+           ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
+         fib_table_entry_delete (fib_index, &prefix, sm->fib_src_low);
+         vec_del1 (sm->fib_entry_reg, i);
+       }
     }
 }
 
 static void
-nat44_ed_add_del_addr_to_fib_foreach_out_if (ip4_address_t *addr, u8 is_add)
+nat44_ed_add_del_interface_fib_reg_entries (ip4_address_t addr, u8 is_add)
 {
   snat_main_t *sm = &snat_main;
   snat_interface_t *i;
@@ -345,42 +491,66 @@ nat44_ed_add_del_addr_to_fib_foreach_out_if (ip4_address_t *addr, u8 is_add)
     {
       if (nat44_ed_is_interface_outside (i))
        {
-         nat44_ed_add_del_addr_to_fib (addr, 32, i->sw_if_index, is_add);
+         if (is_add)
+           {
+             nat44_ed_add_fib_entry_reg (addr, i->sw_if_index);
+           }
+         else
+           {
+             nat44_ed_del_fib_entry_reg (addr, i->sw_if_index);
+           }
        }
     }
   pool_foreach (i, sm->output_feature_interfaces)
     {
       if (nat44_ed_is_interface_outside (i))
        {
-         nat44_ed_add_del_addr_to_fib (addr, 32, i->sw_if_index, is_add);
+         if (is_add)
+           {
+             nat44_ed_add_fib_entry_reg (addr, i->sw_if_index);
+           }
+         else
+           {
+             nat44_ed_del_fib_entry_reg (addr, i->sw_if_index);
+           }
        }
     }
 }
 
 static_always_inline void
-nat44_ed_add_del_addr_to_fib_foreach_addr (u32 sw_if_index, u8 is_add)
+nat44_ed_add_del_nat_addr_fib_reg_entries (u32 sw_if_index, u8 is_add)
 {
   snat_main_t *sm = &snat_main;
   snat_address_t *ap;
 
   vec_foreach (ap, sm->addresses)
     {
-      nat44_ed_add_del_addr_to_fib (&ap->addr, 32, sw_if_index, is_add);
+      if (is_add)
+       {
+         nat44_ed_add_fib_entry_reg (ap->addr, sw_if_index);
+       }
+      else
+       {
+         nat44_ed_del_fib_entry_reg (ap->addr, sw_if_index);
+       }
     }
 }
 
 static_always_inline void
-nat44_ed_add_del_addr_to_fib_foreach_addr_only_sm (u32 sw_if_index, u8 is_add)
+nat44_ed_add_del_sm_fib_reg_entries (u32 sw_if_index, u8 is_add)
 {
   snat_main_t *sm = &snat_main;
   snat_static_mapping_t *m;
 
   pool_foreach (m, sm->static_mappings)
     {
-      if (is_sm_addr_only (m->flags) && !is_sm_identity_nat (m->flags))
+      if (is_add)
        {
-         nat44_ed_add_del_addr_to_fib (&m->external_addr, 32, sw_if_index,
-                                       is_add);
+         nat44_ed_add_fib_entry_reg (m->external_addr, sw_if_index);
+       }
+      else
+       {
+         nat44_ed_del_fib_entry_reg (m->external_addr, sw_if_index);
        }
     }
 }
@@ -417,6 +587,7 @@ nat44_ed_add_address (ip4_address_t *addr, u32 vrf_id, u8 twice_nat)
       vec_add2 (sm->addresses, ap, 1);
     }
 
+  ap->addr_len = ~0;
   ap->fib_index = ~0;
   ap->addr = *addr;
 
@@ -426,24 +597,24 @@ nat44_ed_add_address (ip4_address_t *addr, u32 vrf_id, u8 twice_nat)
        FIB_PROTOCOL_IP4, vrf_id, sm->fib_src_low);
     }
 
-    if (!twice_nat)
-  {
-    // if we don't have enabled interface we don't add address
-    // to fib
-    nat44_ed_add_del_addr_to_fib_foreach_out_if (addr, 1);
-  }
+  if (!twice_nat)
+    {
+      // if we don't have enabled interface we don't add address
+      // to fib
+      nat44_ed_add_del_interface_fib_reg_entries (*addr, 1);
+      nat44_ed_update_outside_if_addresses (ap);
+    }
   return 0;
 }
 
 int
-nat44_ed_del_address (ip4_address_t addr, u8 delete_sm, u8 twice_nat)
+nat44_ed_del_address (ip4_address_t addr, u8 twice_nat)
 {
   snat_main_t *sm = &snat_main;
   snat_address_t *a = 0, *addresses;
   snat_session_t *ses;
   u32 *ses_to_be_removed = 0, *ses_index;
   snat_main_per_thread_data_t *tsm;
-  snat_static_mapping_t *m;
   int j;
 
   addresses = twice_nat ? sm->twice_nat_addresses : sm->addresses;
@@ -462,40 +633,15 @@ nat44_ed_del_address (ip4_address_t addr, u8 delete_sm, u8 twice_nat)
       return VNET_API_ERROR_NO_SUCH_ENTRY;
     }
 
-  if (delete_sm)
-    {
-      pool_foreach (m, sm->static_mappings)
-       {
-         if (m->external_addr.as_u32 == addr.as_u32)
-           {
-             nat44_ed_del_static_mapping (m->local_addr, m->external_addr,
-                                          m->local_port, m->external_port,
-                                          ip_proto_to_nat_proto (m->proto),
-                                          m->vrf_id, ~0, m->flags);
-           }
-       }
-    }
-  else
-    {
-      // TODO: why ?
-      // check if address is used in some static mapping
-      if (is_snat_address_used_in_static_mapping (sm, addr))
-       {
-         nat_log_err ("address used in static mapping");
-         return VNET_API_ERROR_UNSPECIFIED;
-       }
-    }
-
-  if (a->fib_index != ~0)
-    {
-      fib_table_unlock (a->fib_index, FIB_PROTOCOL_IP4, sm->fib_src_low);
-    }
-
-  // delete sessions using address
+  // delete dynamic sessions only
   vec_foreach (tsm, sm->per_thread_data)
     {
       pool_foreach (ses, tsm->sessions)
        {
+         if (ses->flags & SNAT_SESSION_FLAG_STATIC_MAPPING)
+           {
+             continue;
+           }
          if (ses->out2in.addr.as_u32 == addr.as_u32)
            {
              nat44_ed_free_session_data (sm, ses, tsm - sm->per_thread_data,
@@ -511,12 +657,25 @@ nat44_ed_del_address (ip4_address_t addr, u8 delete_sm, u8 twice_nat)
       vec_free (ses_to_be_removed);
     }
 
-    if (!twice_nat)
-  {
-    vec_del1 (sm->addresses, j);
-    nat44_ed_add_del_addr_to_fib_foreach_out_if (&addr, 0);
-  }
-  else { vec_del1 (sm->twice_nat_addresses, j); }
+  if (!twice_nat)
+    {
+      nat44_ed_add_del_interface_fib_reg_entries (addr, 0);
+    }
+
+  if (a->fib_index != ~0)
+    {
+      fib_table_unlock (a->fib_index, FIB_PROTOCOL_IP4, sm->fib_src_low);
+    }
+
+  if (!twice_nat)
+    {
+      vec_del1 (sm->addresses, j);
+    }
+  else
+    {
+      vec_del1 (sm->twice_nat_addresses, j);
+    }
+
   return 0;
 }
 
@@ -609,38 +768,18 @@ nat44_ed_sm_i2o_lookup (snat_main_t *sm, ip4_address_t addr, u16 port,
   return nat44_ed_sm_lookup (sm, &kv);
 }
 
-void
-nat44_ed_add_resolve_record (ip4_address_t l_addr, u16 l_port, u16 e_port,
-                            ip_protocol_t proto, u32 vrf_id, u32 sw_if_index,
-                            u32 flags, ip4_address_t pool_addr, u8 *tag)
-{
-  snat_static_map_resolve_t *rp;
-  snat_main_t *sm = &snat_main;
-
-  vec_add2 (sm->to_resolve, rp, 1);
-  rp->l_addr.as_u32 = l_addr.as_u32;
-  rp->l_port = l_port;
-  rp->e_port = e_port;
-  rp->sw_if_index = sw_if_index;
-  rp->vrf_id = vrf_id;
-  rp->proto = proto;
-  rp->flags = flags;
-  rp->pool_addr = pool_addr;
-  rp->tag = vec_dup (tag);
-}
-
-int
+static snat_static_mapping_resolve_t *
 nat44_ed_get_resolve_record (ip4_address_t l_addr, u16 l_port, u16 e_port,
                             ip_protocol_t proto, u32 vrf_id, u32 sw_if_index,
-                            u32 flags, int *out)
+                            u32 flags, int *out_idx)
 {
-  snat_static_map_resolve_t *rp;
+  snat_static_mapping_resolve_t *rp;
   snat_main_t *sm = &snat_main;
   int i;
 
-  for (i = 0; i < vec_len (sm->to_resolve); i++)
+  for (i = 0; i < vec_len (sm->sm_to_resolve); i++)
     {
-      rp = sm->to_resolve + i;
+      rp = sm->sm_to_resolve + i;
 
       if (rp->sw_if_index == sw_if_index && rp->vrf_id == vrf_id)
        {
@@ -669,27 +808,27 @@ nat44_ed_get_resolve_record (ip4_address_t l_addr, u16 l_port, u16 e_port,
            {
              continue;
            }
-         if (out)
+         if (out_idx)
            {
-             *out = i;
+             *out_idx = i;
            }
-         return 0;
+         return rp;
        }
     }
-  return 1;
+  return NULL;
 }
 
-int
+static int
 nat44_ed_del_resolve_record (ip4_address_t l_addr, u16 l_port, u16 e_port,
                             ip_protocol_t proto, u32 vrf_id, u32 sw_if_index,
                             u32 flags)
 {
   snat_main_t *sm = &snat_main;
   int i;
-  if (!nat44_ed_get_resolve_record (l_addr, l_port, e_port, proto, vrf_id,
-                                   sw_if_index, flags, &i))
+  if (nat44_ed_get_resolve_record (l_addr, l_port, e_port, proto, vrf_id,
+                                  sw_if_index, flags, &i))
     {
-      vec_del1 (sm->to_resolve, i);
+      vec_del1 (sm->sm_to_resolve, i);
       return 0;
     }
   return 1;
@@ -714,27 +853,14 @@ nat44_ed_validate_sm_input (u32 flags)
   return 0;
 }
 
-snat_address_t *
-nat44_ed_addr_lookup (snat_main_t *sm, u32 addr)
-{
-  for (int i = 0; i < vec_len (sm->addresses); ++i)
-    {
-      if (sm->addresses[i].addr.as_u32 == addr)
-       return &sm->addresses[i];
-    }
-  return NULL;
-}
-
 int
 nat44_ed_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
                             u16 l_port, u16 e_port, ip_protocol_t proto,
                             u32 vrf_id, u32 sw_if_index, u32 flags,
                             ip4_address_t pool_addr, u8 *tag)
 {
+  snat_static_mapping_resolve_t *rp;
   snat_main_t *sm = &snat_main;
-  nat44_lb_addr_port_t *local;
-  snat_static_mapping_t *m;
-  u32 fib_index = ~0;
   int rv;
 
   if (!sm->enabled)
@@ -748,27 +874,79 @@ nat44_ed_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
       return rv;
     }
 
-  if (is_sm_addr_only (flags))
+  // interface bound mapping
+  if (is_sm_switch_address (flags))
     {
-      e_port = l_port = proto = 0;
+      if (nat44_ed_get_resolve_record (l_addr, l_port, e_port, proto, vrf_id,
+                                      sw_if_index, flags, 0))
+       {
+         return VNET_API_ERROR_VALUE_EXIST;
+       }
+
+      vec_add2 (sm->sm_to_resolve, rp, 1);
+      rp->l_addr.as_u32 = l_addr.as_u32;
+      rp->l_port = l_port;
+      rp->e_port = e_port;
+      rp->sw_if_index = sw_if_index;
+      rp->vrf_id = vrf_id;
+      rp->proto = proto;
+      rp->flags = flags;
+      rp->pool_addr = pool_addr;
+      rp->tag = vec_dup (tag);
+      rp->is_resolved = 0;
+
+      ip4_address_t *first_int_addr =
+       ip4_interface_first_address (sm->ip4_main, sw_if_index, 0);
+      if (!first_int_addr)
+       {
+         return 0;
+       }
+
+      e_addr.as_u32 = first_int_addr->as_u32;
+      rp->is_resolved = 1;
     }
 
-  if (is_sm_switch_address (flags))
+  rv = nat44_ed_add_static_mapping_internal (l_addr, e_addr, l_port, e_port,
+                                            proto, vrf_id, sw_if_index, flags,
+                                            pool_addr, tag);
+  if ((0 != rv) && is_sm_switch_address (flags))
+    {
+      nat44_ed_del_resolve_record (l_addr, l_port, e_port, proto, vrf_id,
+                                  sw_if_index, flags);
+    }
+
+  return rv;
+}
+
+int
+nat44_ed_del_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
+                            u16 l_port, u16 e_port, ip_protocol_t proto,
+                            u32 vrf_id, u32 sw_if_index, u32 flags)
+{
+  snat_main_t *sm = &snat_main;
+  int rv;
+
+  if (!sm->enabled)
+    {
+      return VNET_API_ERROR_UNSUPPORTED;
+    }
+
+  rv = nat44_ed_validate_sm_input (flags);
+  if (rv != 0)
     {
-      // this mapping is interface bound
-      ip4_address_t *first_int_addr;
+      return rv;
+    }
 
-      // check if this record isn't registered for resolve
-      if (!nat44_ed_get_resolve_record (l_addr, l_port, e_port, proto, vrf_id,
-                                       sw_if_index, flags, 0))
+  // interface bound mapping
+  if (is_sm_switch_address (flags))
+    {
+      if (nat44_ed_del_resolve_record (l_addr, l_port, e_port, proto, vrf_id,
+                                      sw_if_index, flags))
        {
-         return VNET_API_ERROR_VALUE_EXIST;
+         return VNET_API_ERROR_NO_SUCH_ENTRY;
        }
-      // register record for resolve
-      nat44_ed_add_resolve_record (l_addr, l_port, e_port, proto, vrf_id,
-                                  sw_if_index, flags, pool_addr, tag);
 
-      first_int_addr =
+      ip4_address_t *first_int_addr =
        ip4_interface_first_address (sm->ip4_main, sw_if_index, 0);
       if (!first_int_addr)
        {
@@ -779,6 +957,27 @@ nat44_ed_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
       e_addr.as_u32 = first_int_addr->as_u32;
     }
 
+  return nat44_ed_del_static_mapping_internal (l_addr, e_addr, l_port, e_port,
+                                              proto, vrf_id, flags);
+}
+
+static int
+nat44_ed_add_static_mapping_internal (ip4_address_t l_addr,
+                                     ip4_address_t e_addr, u16 l_port,
+                                     u16 e_port, ip_protocol_t proto,
+                                     u32 vrf_id, u32 sw_if_index, u32 flags,
+                                     ip4_address_t pool_addr, u8 *tag)
+{
+  snat_main_t *sm = &snat_main;
+  nat44_lb_addr_port_t *local;
+  snat_static_mapping_t *m;
+  u32 fib_index = ~0;
+
+  if (is_sm_addr_only (flags))
+    {
+      e_port = l_port = proto = 0;
+    }
+
   if (is_sm_identity_nat (flags))
     {
       l_port = e_port;
@@ -788,13 +987,14 @@ nat44_ed_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
   m = nat44_ed_sm_o2i_lookup (sm, e_addr, e_port, 0, proto);
   if (m)
     {
+      // case:
+      // adding local identity nat record for different vrf table
+
       if (!is_sm_identity_nat (m->flags))
        {
          return VNET_API_ERROR_VALUE_EXIST;
        }
 
-      // case:
-      // adding local identity nat record for different vrf table
       pool_foreach (local, m->locals)
        {
          if (local->vrf_id == vrf_id)
@@ -838,21 +1038,6 @@ nat44_ed_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
        }
     }
 
-  if (!(is_sm_out2in_only (flags) || is_sm_addr_only (flags) ||
-       sm->static_mapping_only))
-    {
-      if (!nat44_ed_addr_lookup (sm, e_addr.as_u32))
-       {
-         // remove resolve record
-         if (is_sm_switch_address (flags) && !is_sm_identity_nat (flags))
-           {
-             nat44_ed_del_resolve_record (l_addr, l_port, e_port, proto,
-                                          vrf_id, sw_if_index, flags);
-           }
-         return VNET_API_ERROR_NO_SUCH_ENTRY;
-       }
-    }
-
   pool_get (sm->static_mappings, m);
   clib_memset (m, 0, sizeof (*m));
 
@@ -860,13 +1045,9 @@ nat44_ed_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
   m->local_addr = l_addr;
   m->external_addr = e_addr;
 
+  m->pool_addr = pool_addr;
   m->tag = vec_dup (tag);
 
-  if (is_sm_exact_address (flags) && is_sm_twice_nat (flags))
-    {
-      m->pool_addr = pool_addr;
-    }
-
   if (!is_sm_addr_only (flags))
     {
       m->local_port = l_port;
@@ -885,12 +1066,6 @@ nat44_ed_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
     {
       m->vrf_id = vrf_id;
       m->fib_index = fib_index;
-
-      // not identity && addr only
-      if (is_sm_addr_only (flags))
-       {
-         nat44_ed_add_del_addr_to_fib_foreach_out_if (&e_addr, 1);
-       }
     }
 
   if (!is_sm_out2in_only (flags))
@@ -913,13 +1088,16 @@ nat44_ed_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
       vec_add1 (m->workers, worker_index);
     }
 
+  nat44_ed_add_del_interface_fib_reg_entries (e_addr, 1);
+
   return 0;
 }
 
-int
-nat44_ed_del_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
-                            u16 l_port, u16 e_port, ip_protocol_t proto,
-                            u32 vrf_id, u32 sw_if_index, u32 flags)
+static int
+nat44_ed_del_static_mapping_internal (ip4_address_t l_addr,
+                                     ip4_address_t e_addr, u16 l_port,
+                                     u16 e_port, ip_protocol_t proto,
+                                     u32 vrf_id, u32 flags)
 {
   snat_main_per_thread_data_t *tsm;
   snat_main_t *sm = &snat_main;
@@ -927,47 +1105,12 @@ nat44_ed_del_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
   nat44_lb_addr_port_t *local;
   snat_static_mapping_t *m;
   u32 fib_index = ~0;
-  int rv;
-
-  if (!sm->enabled)
-    {
-      return VNET_API_ERROR_UNSUPPORTED;
-    }
-
-  rv = nat44_ed_validate_sm_input (flags);
-  if (rv != 0)
-    {
-      return rv;
-    }
 
   if (is_sm_addr_only (flags))
     {
       e_port = l_port = proto = 0;
     }
 
-  if (is_sm_switch_address (flags))
-    {
-      // this mapping is interface bound
-      ip4_address_t *first_int_addr;
-
-      // delete record registered for resolve
-      if (nat44_ed_del_resolve_record (l_addr, l_port, e_port, proto, vrf_id,
-                                      sw_if_index, flags))
-       {
-         return VNET_API_ERROR_NO_SUCH_ENTRY;
-       }
-
-      first_int_addr =
-       ip4_interface_first_address (sm->ip4_main, sw_if_index, 0);
-      if (!first_int_addr)
-       {
-         // dhcp resolution required
-         return 0;
-       }
-
-      e_addr.as_u32 = first_int_addr->as_u32;
-    }
-
   if (is_sm_identity_nat (flags))
     {
       l_port = e_port;
@@ -976,21 +1119,16 @@ nat44_ed_del_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
 
   // fib index 0
   m = nat44_ed_sm_o2i_lookup (sm, e_addr, e_port, 0, proto);
-
   if (!m)
     {
-      if (is_sm_switch_address (flags))
-       {
-         return 0;
-       }
       return VNET_API_ERROR_NO_SUCH_ENTRY;
     }
 
   if (is_sm_identity_nat (flags))
     {
-      u8 failure = 1;
+      u8 found = 0;
 
-      if (!is_sm_switch_address (flags))
+      if (vrf_id == ~0)
        {
          vrf_id = sm->inside_vrf_id;
        }
@@ -1002,11 +1140,11 @@ nat44_ed_del_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
              local = pool_elt_at_index (m->locals, local - m->locals);
              fib_index = local->fib_index;
              pool_put (m->locals, local);
-             failure = 0;
+             found = 1;
            }
        }
 
-      if (failure)
+      if (!found)
        {
          return VNET_API_ERROR_NO_SUCH_ENTRY;
        }
@@ -1016,32 +1154,24 @@ nat44_ed_del_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
       fib_index = m->fib_index;
     }
 
-  if (!(is_sm_out2in_only (flags) || is_sm_addr_only (flags) ||
-       sm->static_mapping_only))
-    {
-      if (!nat44_ed_addr_lookup (sm, e_addr.as_u32))
-       {
-         return VNET_API_ERROR_INVALID_VALUE;
-       }
-    }
-
   if (!is_sm_out2in_only (flags))
     {
       nat44_ed_sm_i2o_del (sm, l_addr, l_port, fib_index, proto);
     }
 
-  if (!sm->static_mapping_only || sm->static_mapping_connection_tracking)
+  // delete sessions for static mapping
+  if (sm->num_workers > 1)
     {
-      // delete sessions for static mapping
-      if (sm->num_workers > 1)
-       tsm = vec_elt_at_index (sm->per_thread_data, m->workers[0]);
-      else
-       tsm = vec_elt_at_index (sm->per_thread_data, sm->num_workers);
-
-      nat_ed_static_mapping_del_sessions (
-       sm, tsm, m->local_addr, m->local_port, m->proto, fib_index,
-       is_sm_addr_only (flags), e_addr, e_port);
+      tsm = vec_elt_at_index (sm->per_thread_data, m->workers[0]);
     }
+  else
+    {
+      tsm = vec_elt_at_index (sm->per_thread_data, sm->num_workers);
+    }
+
+  nat_ed_static_mapping_del_sessions (sm, tsm, m->local_addr, m->local_port,
+                                     m->proto, fib_index,
+                                     is_sm_addr_only (flags), e_addr, e_port);
 
   fib_table_unlock (fib_index, FIB_PROTOCOL_IP4, sm->fib_src_low);
 
@@ -1055,10 +1185,7 @@ nat44_ed_del_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
       vec_free (m->workers);
       pool_put (sm->static_mappings, m);
 
-      if (is_sm_addr_only (flags) && !is_sm_identity_nat (flags))
-       {
-         nat44_ed_add_del_addr_to_fib_foreach_out_if (&e_addr, 0);
-       }
+      nat44_ed_add_del_interface_fib_reg_entries (e_addr, 0);
     }
 
   return 0;
@@ -1097,7 +1224,7 @@ nat44_ed_add_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
       return VNET_API_ERROR_INVALID_VALUE;
     }
 
-  if (!(sm->static_mapping_only || is_sm_out2in_only (flags)))
+  if (!is_sm_out2in_only (flags))
     {
       /* Find external address in allocated addresses and reserve port for
         address and port pair mapping when dynamic translations enabled */
@@ -1141,7 +1268,7 @@ nat44_ed_add_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
   if (nat44_ed_sm_o2i_add (sm, m, m->external_addr, m->external_port, 0,
                           m->proto))
     {
-      nat_elog_err (sm, "sm o2i key add failed");
+      nat_log_err ("sm o2i key add failed");
       return VNET_API_ERROR_UNSPECIFIED;
     }
 
@@ -1153,7 +1280,7 @@ nat44_ed_add_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
        {
          if (nat44_ed_sm_o2i_add (sm, m, e_addr, e_port, 0, proto))
            {
-             nat_elog_err (sm, "sm o2i key add failed");
+             nat_log_err ("sm o2i key add failed");
              rc = VNET_API_ERROR_UNSPECIFIED;
              // here we continue with add operation so that it can be safely
              // reversed in delete path - otherwise we'd have to track what
@@ -1216,7 +1343,7 @@ nat44_ed_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
   if (nat44_ed_sm_o2i_del (sm, m->external_addr, m->external_port, 0,
                           m->proto))
     {
-      nat_elog_err (sm, "sm o2i key del failed");
+      nat_log_err ("sm o2i key del failed");
       return VNET_API_ERROR_UNSPECIFIED;
     }
 
@@ -1228,7 +1355,7 @@ nat44_ed_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
          if (nat44_ed_sm_i2o_del (sm, local->addr, local->port,
                                   local->fib_index, m->proto))
            {
-             nat_elog_err (sm, "sm i2o key del failed");
+             nat_log_err ("sm i2o key del failed");
              return VNET_API_ERROR_UNSPECIFIED;
            }
        }
@@ -1337,7 +1464,7 @@ nat44_ed_add_del_lb_static_mapping_local (ip4_address_t e_addr, u16 e_port,
          if (nat44_ed_sm_i2o_add (sm, m, l_addr, l_port, local->fib_index,
                                   proto))
            {
-             nat_elog_err (sm, "sm i2o key add failed");
+             nat_log_err ("sm i2o key add failed");
              pool_put (m->locals, local);
              return VNET_API_ERROR_UNSPECIFIED;
            }
@@ -1358,7 +1485,7 @@ nat44_ed_add_del_lb_static_mapping_local (ip4_address_t e_addr, u16 e_port,
        {
          if (nat44_ed_sm_i2o_del (sm, l_addr, l_port, match_local->fib_index,
                                   proto))
-           nat_elog_err (sm, "sm i2o key del failed");
+           nat_log_err ("sm i2o key del failed");
        }
 
       if (sm->num_workers > 1)
@@ -1606,8 +1733,10 @@ nat44_ed_add_interface (u32 sw_if_index, u8 is_inside)
          outside_fib->refcount = 1;
        }
 
-      nat44_ed_add_del_addr_to_fib_foreach_addr (sw_if_index, 1);
-      nat44_ed_add_del_addr_to_fib_foreach_addr_only_sm (sw_if_index, 1);
+      nat44_ed_add_del_nat_addr_fib_reg_entries (sw_if_index, 1);
+      nat44_ed_add_del_sm_fib_reg_entries (sw_if_index, 1);
+
+      nat44_ed_bind_if_addr_to_nat_addr (sw_if_index);
     }
   else
     {
@@ -1715,8 +1844,8 @@ nat44_ed_del_interface (u32 sw_if_index, u8 is_inside)
            }
        }
 
-      nat44_ed_add_del_addr_to_fib_foreach_addr (sw_if_index, 0);
-      nat44_ed_add_del_addr_to_fib_foreach_addr_only_sm (sw_if_index, 0);
+      nat44_ed_add_del_nat_addr_fib_reg_entries (sw_if_index, 0);
+      nat44_ed_add_del_sm_fib_reg_entries (sw_if_index, 0);
     }
 
   return 0;
@@ -1814,8 +1943,10 @@ nat44_ed_add_output_interface (u32 sw_if_index)
       outside_fib->refcount = 1;
     }
 
-  nat44_ed_add_del_addr_to_fib_foreach_addr (sw_if_index, 1);
-  nat44_ed_add_del_addr_to_fib_foreach_addr_only_sm (sw_if_index, 1);
+  nat44_ed_add_del_nat_addr_fib_reg_entries (sw_if_index, 1);
+  nat44_ed_add_del_sm_fib_reg_entries (sw_if_index, 1);
+
+  nat44_ed_bind_if_addr_to_nat_addr (sw_if_index);
 
   return 0;
 }
@@ -1900,8 +2031,8 @@ nat44_ed_del_output_interface (u32 sw_if_index)
        }
     }
 
-  nat44_ed_add_del_addr_to_fib_foreach_addr (sw_if_index, 0);
-  nat44_ed_add_del_addr_to_fib_foreach_addr_only_sm (sw_if_index, 0);
+  nat44_ed_add_del_nat_addr_fib_reg_entries (sw_if_index, 0);
+  nat44_ed_add_del_sm_fib_reg_entries (sw_if_index, 0);
 
   return 0;
 }
@@ -1958,7 +2089,7 @@ nat44_ed_update_outside_fib_cb (ip4_main_t *im, uword opaque, u32 sw_if_index,
     }
 
   pool_foreach (i, sm->interfaces)
-     {
+    {
       if (i->sw_if_index == sw_if_index)
         {
          if (!(nat44_ed_is_interface_outside (i)))
@@ -1968,7 +2099,7 @@ nat44_ed_update_outside_fib_cb (ip4_main_t *im, uword opaque, u32 sw_if_index,
     }
 
   pool_foreach (i, sm->output_feature_interfaces)
-     {
+    {
       if (i->sw_if_index == sw_if_index)
         {
          if (!(nat44_ed_is_interface_outside (i)))
@@ -1981,25 +2112,25 @@ nat44_ed_update_outside_fib_cb (ip4_main_t *im, uword opaque, u32 sw_if_index,
     return;
 
   vec_foreach (outside_fib, sm->outside_fibs)
-  {
-    if (outside_fib->fib_index == old_fib_index)
-      {
-       outside_fib->refcount--;
-       if (!outside_fib->refcount)
-         vec_del1 (sm->outside_fibs, outside_fib - sm->outside_fibs);
-       break;
-      }
-  }
+    {
+      if (outside_fib->fib_index == old_fib_index)
+       {
+         outside_fib->refcount--;
+         if (!outside_fib->refcount)
+           vec_del1 (sm->outside_fibs, outside_fib - sm->outside_fibs);
+         break;
+       }
+    }
 
   vec_foreach (outside_fib, sm->outside_fibs)
-  {
-    if (outside_fib->fib_index == new_fib_index)
-      {
-       outside_fib->refcount++;
-       is_add = 0;
-       break;
-      }
-  }
+    {
+      if (outside_fib->fib_index == new_fib_index)
+       {
+         outside_fib->refcount++;
+         is_add = 0;
+         break;
+       }
+    }
 
   if (is_add)
     {
@@ -2017,7 +2148,7 @@ static void nat44_ed_add_del_interface_address_cb (
   ip4_main_t *im, uword opaque, u32 sw_if_index, ip4_address_t *address,
   u32 address_length, u32 if_address_index, u32 is_delete);
 
-static void nat44_ed_add_del_static_mapping_addr_only_cb (
+static void nat44_ed_add_del_static_mapping_cb (
   ip4_main_t *im, uword opaque, u32 sw_if_index, ip4_address_t *address,
   u32 address_length, u32 if_address_index, u32 is_delete);
 
@@ -2206,7 +2337,7 @@ nat_init (vlib_main_t * vm)
   /* callbacks to call when interface address changes. */
   cbi.function = nat44_ed_add_del_interface_address_cb;
   vec_add1 (sm->ip4_main->add_del_interface_address_callbacks, cbi);
-  cbi.function = nat44_ed_add_del_static_mapping_addr_only_cb;
+  cbi.function = nat44_ed_add_del_static_mapping_cb;
   vec_add1 (sm->ip4_main->add_del_interface_address_callbacks, cbi);
 
   /* callbacks to call when interface to table biding changes */
@@ -2235,19 +2366,8 @@ nat44_plugin_enable (nat44_config_t c)
 
   fail_if_enabled ();
 
-  if (c.static_mapping_only && !c.connection_tracking)
-    {
-      nat_log_err ("unsupported combination of configuration");
-      return 1;
-    }
-
-  sm->static_mapping_only = c.static_mapping_only;
-  sm->static_mapping_connection_tracking = c.connection_tracking;
-
   sm->forwarding_enabled = 0;
   sm->mss_clamping = 0;
-  sm->pat = (!c.static_mapping_only ||
-            (c.static_mapping_only && c.connection_tracking));
 
   if (!c.sessions)
     c.sessions = 63 * 1024;
@@ -2306,22 +2426,52 @@ nat44_plugin_enable (nat44_config_t c)
   return 0;
 }
 
-void
-nat44_addresses_free (snat_address_t ** addresses)
+int
+nat44_ed_del_addresses ()
 {
-  vec_free (*addresses);
-  *addresses = 0;
+  snat_main_t *sm = &snat_main;
+  snat_address_t *a, *vec;
+  int error = 0;
+
+  vec = vec_dup (sm->addresses);
+  vec_foreach (a, vec)
+    {
+      error = nat44_ed_del_address (a->addr, 0);
+      if (error)
+       {
+         nat_log_err ("error occurred while removing adderess");
+       }
+    }
+  vec_free (vec);
+  vec_free (sm->addresses);
+  sm->addresses = 0;
+
+  vec = vec_dup (sm->twice_nat_addresses);
+  vec_foreach (a, vec)
+    {
+      error = nat44_ed_del_address (a->addr, 1);
+      if (error)
+       {
+         nat_log_err ("error occurred while removing adderess");
+       }
+    }
+  vec_free (vec);
+  vec_free (sm->twice_nat_addresses);
+  sm->twice_nat_addresses = 0;
+
+  vec_free (sm->addr_to_resolve);
+  sm->addr_to_resolve = 0;
+
+  return error;
 }
 
 int
-nat44_plugin_disable ()
+nat44_ed_del_interfaces ()
 {
   snat_main_t *sm = &snat_main;
   snat_interface_t *i, *pool;
   int error = 0;
 
-  fail_if_disabled ();
-
   pool = pool_dup (sm->interfaces);
   pool_foreach (i, pool)
     {
@@ -2333,51 +2483,109 @@ nat44_plugin_disable ()
        {
          error = nat44_ed_del_interface (i->sw_if_index, 0);
        }
+
       if (error)
-        {
-          nat_log_err ("error occurred while removing interface %u",
-                       i->sw_if_index);
-        }
+       {
+         nat_log_err ("error occurred while removing interface");
+       }
     }
-  pool_free (sm->interfaces);
   pool_free (pool);
+  pool_free (sm->interfaces);
   sm->interfaces = 0;
+  return error;
+}
+
+int
+nat44_ed_del_output_interfaces ()
+{
+  snat_main_t *sm = &snat_main;
+  snat_interface_t *i, *pool;
+  int error = 0;
 
   pool = pool_dup (sm->output_feature_interfaces);
   pool_foreach (i, pool)
     {
       error = nat44_ed_del_output_interface (i->sw_if_index);
       if (error)
-        {
-          nat_log_err ("error occurred while removing interface %u",
-                       i->sw_if_index);
-        }
+       {
+         nat_log_err ("error occurred while removing output interface");
+       }
     }
-  pool_free (sm->output_feature_interfaces);
   pool_free (pool);
+  pool_free (sm->output_feature_interfaces);
   sm->output_feature_interfaces = 0;
+  return error;
+}
 
-  vec_free (sm->max_translations_per_fib);
+int
+nat44_ed_del_static_mappings ()
+{
+  snat_main_t *sm = &snat_main;
+  snat_static_mapping_t *m, *pool;
+  int error = 0;
+
+  pool = pool_dup (sm->static_mappings);
+  pool_foreach (m, pool)
+    {
+      error = nat44_ed_del_static_mapping_internal (
+       m->local_addr, m->external_addr, m->local_port, m->external_port,
+       m->proto, m->vrf_id, m->flags);
+      if (error)
+       {
+         nat_log_err ("error occurred while removing mapping");
+       }
+    }
+  pool_free (pool);
+  pool_free (sm->static_mappings);
+  sm->static_mappings = 0;
+
+  vec_free (sm->sm_to_resolve);
+  sm->sm_to_resolve = 0;
+
+  return error;
+}
+
+int
+nat44_plugin_disable ()
+{
+  snat_main_per_thread_data_t *tsm;
+  snat_main_t *sm = &snat_main;
+  int rc, error = 0;
+
+  fail_if_disabled ();
 
-  nat44_ed_db_free ();
+  rc = nat44_ed_del_static_mappings ();
+  if (rc)
+    error = 1;
 
-  nat44_addresses_free (&sm->addresses);
-  nat44_addresses_free (&sm->twice_nat_addresses);
+  rc = nat44_ed_del_addresses ();
+  if (rc)
+    error = 1;
 
-  vec_free (sm->to_resolve);
-  vec_free (sm->auto_add_sw_if_indices);
-  vec_free (sm->auto_add_sw_if_indices_twice_nat);
+  rc = nat44_ed_del_interfaces ();
+  if (rc)
+    error = 1;
 
-  sm->to_resolve = 0;
-  sm->auto_add_sw_if_indices = 0;
-  sm->auto_add_sw_if_indices_twice_nat = 0;
+  rc = nat44_ed_del_output_interfaces ();
+  if (rc)
+    error = 1;
 
-  sm->forwarding_enabled = 0;
+  vec_free (sm->max_translations_per_fib);
+  sm->max_translations_per_fib = 0;
+
+  clib_bihash_free_16_8 (&sm->flow_hash);
+
+  vec_foreach (tsm, sm->per_thread_data)
+    {
+      nat44_ed_worker_db_free (tsm);
+    }
 
-  sm->enabled = 0;
   clib_memset (&sm->rconfig, 0, sizeof (sm->rconfig));
 
-  return 0;
+  sm->forwarding_enabled = 0;
+  sm->enabled = 0;
+
+  return error;
 }
 
 void
@@ -2992,13 +3200,10 @@ nat44_ed_db_init (u32 translations, u32 translation_buckets)
 
   reinit_ed_flow_hash ();
 
-  if (sm->pat)
+  vec_foreach (tsm, sm->per_thread_data)
     {
-      vec_foreach (tsm, sm->per_thread_data)
-       {
-         nat44_ed_worker_db_init (tsm, sm->max_translations_per_thread,
-                                  sm->translation_buckets);
-       }
+      nat44_ed_worker_db_init (tsm, sm->max_translations_per_thread,
+                              sm->translation_buckets);
     }
 }
 
@@ -3010,24 +3215,6 @@ nat44_ed_worker_db_free (snat_main_per_thread_data_t *tsm)
   vec_free (tsm->per_vrf_sessions_vec);
 }
 
-static void
-nat44_ed_db_free ()
-{
-  snat_main_t *sm = &snat_main;
-  snat_main_per_thread_data_t *tsm;
-
-  pool_free (sm->static_mappings);
-  clib_bihash_free_16_8 (&sm->flow_hash);
-
-  if (sm->pat)
-    {
-      vec_foreach (tsm, sm->per_thread_data)
-       {
-         nat44_ed_worker_db_free (tsm);
-       }
-    }
-}
-
 void
 nat44_ed_sessions_clear ()
 {
@@ -3036,90 +3223,105 @@ nat44_ed_sessions_clear ()
 
   reinit_ed_flow_hash ();
 
-  if (sm->pat)
+  vec_foreach (tsm, sm->per_thread_data)
     {
-      vec_foreach (tsm, sm->per_thread_data)
-       {
-
-         nat44_ed_worker_db_free (tsm);
-         nat44_ed_worker_db_init (tsm, sm->max_translations_per_thread,
-                                  sm->translation_buckets);
-       }
+      nat44_ed_worker_db_free (tsm);
+      nat44_ed_worker_db_init (tsm, sm->max_translations_per_thread,
+                              sm->translation_buckets);
     }
   vlib_zero_simple_counter (&sm->total_sessions, 0);
 }
 
 static void
-nat44_ed_add_del_static_mapping_addr_only_cb (
-  ip4_main_t *im, uword opaque, u32 sw_if_index, ip4_address_t *address,
-  u32 address_length, u32 if_address_index, u32 is_delete)
+nat44_ed_add_del_static_mapping_cb (ip4_main_t *im, uword opaque,
+                                   u32 sw_if_index, ip4_address_t *address,
+                                   u32 address_length, u32 if_address_index,
+                                   u32 is_delete)
 {
-  snat_static_map_resolve_t *rp;
+  snat_static_mapping_resolve_t *rp;
   snat_main_t *sm = &snat_main;
-  snat_static_mapping_t *m;
-  int i, rv = 0, match = 0;
+  int rv = 0;
 
   if (!sm->enabled)
     {
       return;
     }
 
-  // find first addr_only resolve record by sw_if_index
-  for (i = 0; i < vec_len (sm->to_resolve); i++)
+  vec_foreach (rp, sm->sm_to_resolve)
     {
-      rp = sm->to_resolve + i;
-      if (rp->addr_only && rp->sw_if_index == sw_if_index)
+      if (sw_if_index == rp->sw_if_index)
        {
-         match = 1;
-         break;
+         if (is_delete)
+           {
+             if (rp->is_resolved)
+               {
+                 rv = nat44_ed_del_static_mapping_internal (
+                   rp->l_addr, address[0], rp->l_port, rp->e_port, rp->proto,
+                   rp->vrf_id, rp->flags);
+                 if (rv)
+                   {
+                     nat_log_err ("ed del static mapping failed");
+                   }
+                 else
+                   {
+                     rp->is_resolved = 0;
+                   }
+               }
+           }
+         else
+           {
+             if (!rp->is_resolved)
+               {
+                 rv = nat44_ed_add_static_mapping_internal (
+                   rp->l_addr, address[0], rp->l_port, rp->e_port, rp->proto,
+                   rp->vrf_id, ~0, rp->flags, rp->pool_addr, rp->tag);
+                 if (rv)
+                   {
+                     nat_log_err ("ed add static mapping failed");
+                   }
+                 else
+                   {
+                     rp->is_resolved = 1;
+                   }
+               }
+           }
        }
     }
-  if (!match)
-    {
-      return;
-    }
+}
 
-  m = nat44_ed_sm_o2i_lookup (sm, *address, rp->addr_only ? 0 : rp->e_port, 0,
-                             rp->proto);
+static int
+nat44_ed_get_addr_resolve_record (u32 sw_if_index, u8 twice_nat, int *out)
+{
+  snat_main_t *sm = &snat_main;
+  snat_address_resolve_t *rp;
+  int i;
 
-  if (is_delete)
-    {
-      if (m)
-       {
-         rv = nat44_ed_del_static_mapping (rp->l_addr, address[0], rp->l_port,
-                                           rp->e_port, rp->proto, rp->vrf_id,
-                                           ~0, rp->flags);
-       }
-    }
-  else
+  for (i = 0; i < vec_len (sm->addr_to_resolve); i++)
     {
-      if (!m)
+      rp = sm->addr_to_resolve + i;
+
+      if ((rp->sw_if_index == sw_if_index) && (rp->is_twice_nat == twice_nat))
        {
-         rv = nat44_ed_add_static_mapping (
-           rp->l_addr, address[0], rp->l_port, rp->e_port, rp->proto,
-           rp->vrf_id, ~0, rp->flags, rp->pool_addr, rp->tag);
+         if (out)
+           {
+             *out = i;
+           }
+         return 0;
        }
-      // else: don't trip over lease renewal, static config
-    }
-  if (rv)
-    {
-      nat_elog_notice_X1 (sm, "nat44_ed_del_static_mapping returned %d", "i4",
-                         rv);
     }
+  return 1;
 }
-
-static_always_inline int
-is_sw_if_index_reg_for_auto_resolve (u32 *sw_if_indices, u32 sw_if_index)
+static int
+nat44_ed_del_addr_resolve_record (u32 sw_if_index, u8 twice_nat)
 {
-  u32 *i;
-  vec_foreach (i, sw_if_indices)
+  snat_main_t *sm = &snat_main;
+  int i;
+  if (!nat44_ed_get_addr_resolve_record (sw_if_index, twice_nat, &i))
     {
-      if (*i == sw_if_index)
-       {
-         return 1;
-       }
+      vec_del1 (sm->addr_to_resolve, i);
+      return 0;
     }
-  return 0;
+  return 1;
 }
 
 static void
@@ -3129,69 +3331,78 @@ nat44_ed_add_del_interface_address_cb (ip4_main_t *im, uword opaque,
                                       u32 if_address_index, u32 is_delete)
 {
   snat_main_t *sm = &snat_main;
-  snat_static_map_resolve_t *rp;
-  snat_address_t *addresses = sm->addresses;
+  snat_address_resolve_t *arp;
+  snat_address_t *ap;
   u8 twice_nat = 0;
-  int rv, i;
+  int i, rv;
 
   if (!sm->enabled)
     {
       return;
     }
 
-  if (!is_sw_if_index_reg_for_auto_resolve (sm->auto_add_sw_if_indices,
-                                           sw_if_index))
+  if (nat44_ed_get_addr_resolve_record (sw_if_index, twice_nat, &i))
     {
-      if (!is_sw_if_index_reg_for_auto_resolve (
-           sm->auto_add_sw_if_indices_twice_nat, sw_if_index))
+      twice_nat = 1;
+      if (nat44_ed_get_addr_resolve_record (sw_if_index, twice_nat, &i))
        {
+         u32 fib_index =
+           ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
+         vec_foreach (ap, sm->addresses)
+           {
+             if ((fib_index == ap->fib_index) &&
+                 (address->as_u32 == ap->addr.as_u32))
+               {
+                 if (!is_delete)
+                   {
+                     ap->addr_len = address_length;
+                     ap->sw_if_index = sw_if_index;
+                     ap->net.as_u32 = (ap->addr.as_u32 >> (32 - ap->addr_len))
+                                      << (32 - ap->addr_len);
+
+                     nat_log_debug (
+                       "pool addr %U binds to -> sw_if_idx: %u net: %U/%u",
+                       format_ip4_address, &ap->addr, ap->sw_if_index,
+                       format_ip4_address, &ap->net, ap->addr_len);
+                   }
+                 else
+                   {
+                     ap->addr_len = ~0;
+                   }
+                 break;
+               }
+           }
          return;
        }
-      else
-       {
-         addresses = sm->twice_nat_addresses;
-         twice_nat = 1;
-       }
     }
 
+  arp = sm->addr_to_resolve + i;
+
   if (!is_delete)
     {
-      // don't trip over lease renewal, static config
-      for (i = 0; i < vec_len (addresses); i++)
+      if (arp->is_resolved)
        {
-         if (addresses[i].addr.as_u32 == address->as_u32)
-           {
-             return;
-           }
+         return;
        }
 
-      (void) nat44_ed_add_address (address, ~0, twice_nat);
-
-      // scan static mapping switch address resolution record vector
-      for (i = 0; i < vec_len (sm->to_resolve); i++)
+      rv = nat44_ed_add_address (address, ~0, arp->is_twice_nat);
+      if (0 == rv)
        {
-         rp = sm->to_resolve + i;
-         if (rp->addr_only)
-           {
-             continue;
-           }
-         if (rp->sw_if_index == sw_if_index)
-           {
-             rv = nat44_ed_add_static_mapping (
-               rp->l_addr, address[0], rp->l_port, rp->e_port, rp->proto,
-               rp->vrf_id, ~0, rp->flags, rp->pool_addr, rp->tag);
-             if (rv)
-               {
-                 nat_elog_notice_X1 (sm, "add_static_mapping returned %d",
-                                     "i4", rv);
-               }
-           }
+         arp->is_resolved = 1;
        }
     }
   else
     {
-      // remove all static mapping records
-      (void) nat44_ed_del_address (address[0], 1, twice_nat);
+      if (!arp->is_resolved)
+       {
+         return;
+       }
+
+      rv = nat44_ed_del_address (address[0], arp->is_twice_nat);
+      if (0 == rv)
+       {
+         arp->is_resolved = 0;
+       }
     }
 }
 
@@ -3201,34 +3412,34 @@ nat44_ed_add_interface_address (u32 sw_if_index, u8 twice_nat)
   snat_main_t *sm = &snat_main;
   ip4_main_t *ip4_main = sm->ip4_main;
   ip4_address_t *first_int_addr;
-  u32 *auto_add_sw_if_indices = twice_nat ?
-                                 sm->auto_add_sw_if_indices_twice_nat :
-                                 sm->auto_add_sw_if_indices;
-  int i;
+  snat_address_resolve_t *ap;
+  int rv;
 
-  for (i = 0; i < vec_len (auto_add_sw_if_indices); i++)
+  if (!sm->enabled)
     {
-      if (auto_add_sw_if_indices[i] == sw_if_index)
-       {
-         return VNET_API_ERROR_VALUE_EXIST;
-       }
+      return VNET_API_ERROR_UNSUPPORTED;
     }
 
-  // add to the auto-address list
-  if (twice_nat)
-    {
-      vec_add1 (sm->auto_add_sw_if_indices_twice_nat, sw_if_index);
-    }
-  else
+  if (!nat44_ed_get_addr_resolve_record (sw_if_index, twice_nat, 0))
     {
-      vec_add1 (sm->auto_add_sw_if_indices, sw_if_index);
+      return VNET_API_ERROR_VALUE_EXIST;
     }
 
-  // if the address is already bound - or static - add it now
+  vec_add2 (sm->addr_to_resolve, ap, 1);
+  ap->sw_if_index = sw_if_index;
+  ap->is_twice_nat = twice_nat;
+  ap->is_resolved = 0;
+
   first_int_addr = ip4_interface_first_address (ip4_main, sw_if_index, 0);
   if (first_int_addr)
     {
-      (void) nat44_ed_add_address (first_int_addr, ~0, twice_nat);
+      rv = nat44_ed_add_address (first_int_addr, ~0, twice_nat);
+      if (0 != rv)
+       {
+         nat44_ed_del_addr_resolve_record (sw_if_index, twice_nat);
+         return rv;
+       }
+      ap->is_resolved = 1;
     }
 
   return 0;
@@ -3240,62 +3451,24 @@ nat44_ed_del_interface_address (u32 sw_if_index, u8 twice_nat)
   snat_main_t *sm = &snat_main;
   ip4_main_t *ip4_main = sm->ip4_main;
   ip4_address_t *first_int_addr;
-  snat_static_map_resolve_t *rp;
-  u32 *indices_to_delete = 0;
-  int i, j;
-  u32 *auto_add_sw_if_indices;
 
   if (!sm->enabled)
     {
       return VNET_API_ERROR_UNSUPPORTED;
     }
 
-  auto_add_sw_if_indices = twice_nat ? sm->auto_add_sw_if_indices_twice_nat :
-                                      sm->auto_add_sw_if_indices;
-
-  for (i = 0; i < vec_len (auto_add_sw_if_indices); i++)
+  if (nat44_ed_del_addr_resolve_record (sw_if_index, twice_nat))
     {
-      if (auto_add_sw_if_indices[i] == sw_if_index)
-       {
-         first_int_addr =
-           ip4_interface_first_address (ip4_main, sw_if_index, 0);
-         if (first_int_addr)
-           {
-             // remove all static mapping records
-             (void) nat44_ed_del_address (first_int_addr[0], 1, twice_nat);
-           }
-         else
-           {
-             for (j = 0; j < vec_len (sm->to_resolve); j++)
-               {
-                 rp = sm->to_resolve + j;
-                 if (rp->sw_if_index == sw_if_index)
-                   {
-                     vec_add1 (indices_to_delete, j);
-                   }
-               }
-             if (vec_len (indices_to_delete))
-               {
-                 for (j = vec_len (indices_to_delete) - 1; j >= 0; j--)
-                   {
-                     vec_del1 (sm->to_resolve, j);
-                   }
-                 vec_free (indices_to_delete);
-               }
-           }
+      return VNET_API_ERROR_NO_SUCH_ENTRY;
+    }
 
-         if (twice_nat)
-           {
-             vec_del1 (sm->auto_add_sw_if_indices_twice_nat, i);
-           }
-         else
-           {
-             vec_del1 (sm->auto_add_sw_if_indices, i);
-           }
-         return 0;
-       }
+  first_int_addr = ip4_interface_first_address (ip4_main, sw_if_index, 0);
+  if (first_int_addr)
+    {
+      return nat44_ed_del_address (first_int_addr[0], twice_nat);
     }
-  return VNET_API_ERROR_NO_SUCH_ENTRY;
+
+  return 0;
 }
 
 int