NAT64 to use IPv4 address from interface (VPP-1051)

Change-Id: I326429c31dea6958a342ee152ef86cb975f4b12c
Signed-off-by: Matus Fabian <matfabia@cisco.com>

7 files changed, 249 insertions, 1 deletions

diff --git a/src/plugins/nat/nat.api b/src/plugins/nat/nat.api
index d8fdf7283cf..9a000d5611f 100644
--- a/src/plugins/nat/nat.api
+++ b/src/plugins/nat/nat.api
@@ -1649,6 +1649,20 @@ define nat64_prefix_details {
   u32 vrf_id;
 };
 
+/** \brief Add/delete NAT64 pool address from specific interfce
+    @param client_index - opaque cookie to identify the sender
+    @param context - sender context, to match reply w/ request
+    @param is_add - 1 if add, 0 if delete
+    @param sw_if_index - software index of the interface
+*/
+autoreply define nat64_add_del_interface_addr {
+  u32 client_index;
+  u32 context;
+  u8 is_add;
+  u8 is_inside;
+  u32 sw_if_index;
+};
+
 
 /*
  * DS-Lite APIs
diff --git a/src/plugins/nat/nat64.c b/src/plugins/nat/nat64.c
index 952ca8fb11b..936ea9e9988 100644
--- a/src/plugins/nat/nat64.c
+++ b/src/plugins/nat/nat64.c
@@ -47,12 +47,47 @@ static u8 well_known_prefix[] = {
 
 /* *INDENT-ON* */
 
+static void
+nat64_ip4_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)
+{
+  nat64_main_t *nm = &nat64_main;
+  int i, j;
+
+  for (i = 0; i < vec_len (nm->auto_add_sw_if_indices); i++)
+    {
+      if (sw_if_index == nm->auto_add_sw_if_indices[i])
+	{
+	  if (!is_delete)
+	    {
+	      /* Don't trip over lease renewal, static config */
+	      for (j = 0; j < vec_len (nm->addr_pool); j++)
+		if (nm->addr_pool[j].addr.as_u32 == address->as_u32)
+		  return;
+
+	      (void) nat64_add_del_pool_addr (address, ~0, 1);
+	      return;
+	    }
+	  else
+	    {
+	      (void) nat64_add_del_pool_addr (address, ~0, 0);
+	      return;
+	    }
+	}
+    }
+}
+
 clib_error_t *
 nat64_init (vlib_main_t * vm)
 {
   nat64_main_t *nm = &nat64_main;
   clib_error_t *error = 0;
   vlib_thread_main_t *tm = vlib_get_thread_main ();
+  ip4_add_del_interface_address_callback_t cb4;
+  ip4_main_t *im = &ip4_main;
 
   nm->is_disabled = 0;
 
@@ -75,6 +110,12 @@ nat64_init (vlib_main_t * vm)
   nm->tcp_est_timeout = SNAT_TCP_ESTABLISHED_TIMEOUT;
   nm->tcp_incoming_syn_timeout = SNAT_TCP_INCOMING_SYN;
 
+  /* Set up the interface address add/del callback */
+  cb4.function = nat64_ip4_add_del_interface_address_cb;
+  cb4.function_opaque = 0;
+  vec_add1 (im->add_del_interface_address_callbacks, cb4);
+  nm->ip4_main = im;
+
 error:
   return error;
 }
@@ -163,6 +204,47 @@ nat64_pool_addr_walk (nat64_pool_addr_walk_fn_t fn, void *ctx)
 }
 
 int
+nat64_add_interface_address (u32 sw_if_index, int is_add)
+{
+  nat64_main_t *nm = &nat64_main;
+  ip4_main_t *ip4_main = nm->ip4_main;
+  ip4_address_t *first_int_addr;
+  int i;
+
+  first_int_addr = ip4_interface_first_address (ip4_main, sw_if_index, 0);
+
+  for (i = 0; i < vec_len (nm->auto_add_sw_if_indices); i++)
+    {
+      if (nm->auto_add_sw_if_indices[i] == sw_if_index)
+	{
+	  if (is_add)
+	    return VNET_API_ERROR_VALUE_EXIST;
+	  else
+	    {
+	      /* if have address remove it */
+	      if (first_int_addr)
+		(void) nat64_add_del_pool_addr (first_int_addr, ~0, 0);
+
+	      vec_del1 (nm->auto_add_sw_if_indices, i);
+	      return 0;
+	    }
+	}
+    }
+
+  if (!is_add)
+    return VNET_API_ERROR_NO_SUCH_ENTRY;
+
+  /* add to the auto-address list */
+  vec_add1 (nm->auto_add_sw_if_indices, sw_if_index);
+
+  /* If the address is already bound - or static - add it now */
+  if (first_int_addr)
+    (void) nat64_add_del_pool_addr (first_int_addr, ~0, 1);
+
+  return 0;
+}
+
+int
 nat64_add_del_interface (u32 sw_if_index, u8 is_inside, u8 is_add)
 {
   nat64_main_t *nm = &nat64_main;
diff --git a/src/plugins/nat/nat64.h b/src/plugins/nat/nat64.h
index 68224cab013..118076705cc 100644
--- a/src/plugins/nat/nat64.h
+++ b/src/plugins/nat/nat64.h
@@ -55,6 +55,9 @@ typedef struct
   /** Address pool vector */
   snat_address_t *addr_pool;
 
+  /** sw_if_indices whose interface addresses should be auto-added */
+  u32 *auto_add_sw_if_indices;
+
   /** Pref64 vector */
   nat64_prefix_t *pref64;
 
@@ -70,6 +73,7 @@ typedef struct
 
   u8 is_disabled;
 
+  ip4_main_t *ip4_main;
   snat_main_t *sm;
 } nat64_main_t;
 
@@ -103,6 +107,16 @@ typedef int (*nat64_pool_addr_walk_fn_t) (snat_address_t * addr, void *ctx);
 void nat64_pool_addr_walk (nat64_pool_addr_walk_fn_t fn, void *ctx);
 
 /**
+ * @brief NAT64 pool address from specific (DHCP addressed) interface.
+ *
+ * @param sw_if_index Index of the interface.
+ * @param is_add      1 if add, 0 if delete.
+ *
+ * @returns 0 on success, non-zero value otherwise.
+ */
+int nat64_add_interface_address (u32 sw_if_index, int is_add);
+
+/**
  * @brief Enable/disable NAT64 feature on the interface.
  *
  * @param sw_if_index Index of the interface.
diff --git a/src/plugins/nat/nat64_cli.c b/src/plugins/nat/nat64_cli.c
index 7fea6bbb983..3e15beeee3b 100644
--- a/src/plugins/nat/nat64_cli.c
+++ b/src/plugins/nat/nat64_cli.c
@@ -807,6 +807,61 @@ nat64_show_prefix_command_fn (vlib_main_t * vm, unformat_input_t * input,
   return 0;
 }
 
+static clib_error_t *
+nat64_add_interface_address_command_fn (vlib_main_t * vm,
+					unformat_input_t * input,
+					vlib_cli_command_t * cmd)
+{
+  nat64_main_t *nm = &nat64_main;
+  vnet_main_t *vnm = vnet_get_main ();
+  unformat_input_t _line_input, *line_input = &_line_input;
+  u32 sw_if_index;
+  int rv;
+  int is_add = 1;
+  clib_error_t *error = 0;
+
+  if (nm->is_disabled)
+    return clib_error_return (0,
+			      "NAT64 disabled, multi thread not supported");
+  /* Get a line of input. */
+  if (!unformat_user (input, unformat_line_input, line_input))
+    return 0;
+
+  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat
+	  (line_input, "%U", unformat_vnet_sw_interface, vnm, &sw_if_index))
+	;
+      else if (unformat (line_input, "del"))
+	is_add = 0;
+      else
+	{
+	  error = clib_error_return (0, "unknown input '%U'",
+				     format_unformat_error, line_input);
+	  goto done;
+	}
+    }
+
+  rv = nat64_add_interface_address (sw_if_index, is_add);
+
+  switch (rv)
+    {
+    case VNET_API_ERROR_NO_SUCH_ENTRY:
+      error = clib_error_return (0, "entry not exist");
+      break;
+    case VNET_API_ERROR_VALUE_EXIST:
+      error = clib_error_return (0, "entry exist");
+      break;
+    default:
+      break;
+    }
+
+done:
+  unformat_free (line_input);
+
+  return error;
+}
+
 /* *INDENT-OFF* */
 
 /*?
@@ -1017,6 +1072,19 @@ VLIB_CLI_COMMAND (show_nat64_prefix_command, static) = {
   .function = nat64_show_prefix_command_fn,
 };
 
+/*?
+ * @cliexpar
+ * @cliexstart{nat64 add interface address}
+ * Add/delete NAT64 pool address from specific (DHCP addressed) interface.
+ * To add NAT64 pool address from specific interface use:
+ *  vpp# nat64 add interface address GigabitEthernet0/8/0
+ * @cliexend
+?*/
+VLIB_CLI_COMMAND (nat64_add_interface_address_command, static) = {
+    .path = "nat64 add interface address",
+    .short_help = "nat64 add interface address <interface> [del]",
+    .function = nat64_add_interface_address_command_fn,
+};
 /* *INDENT-ON* */
 
 /*
diff --git a/src/plugins/nat/nat_api.c b/src/plugins/nat/nat_api.c
index 548a9e03bc4..127a2b80bbf 100644
--- a/src/plugins/nat/nat_api.c
+++ b/src/plugins/nat/nat_api.c
@@ -3431,6 +3431,44 @@ vl_api_nat64_prefix_dump_t_print (vl_api_nat64_prefix_dump_t * mp,
   FINISH;
 }
 
+static void
+  vl_api_nat64_add_del_interface_addr_t_handler
+  (vl_api_nat64_add_del_interface_addr_t * mp)
+{
+  nat64_main_t *nm = &nat64_main;
+  snat_main_t *sm = &snat_main;
+  vl_api_nat64_add_del_interface_addr_reply_t *rmp;
+  u32 sw_if_index = ntohl (mp->sw_if_index);
+  int rv = 0;
+
+  if (nm->is_disabled)
+    {
+      rv = VNET_API_ERROR_FEATURE_DISABLED;
+      goto send_reply;
+    }
+
+  VALIDATE_SW_IF_INDEX (mp);
+
+  rv = nat64_add_interface_address (sw_if_index, mp->is_add);
+
+  BAD_SW_IF_INDEX_LABEL;
+send_reply:
+  REPLY_MACRO (VL_API_NAT64_ADD_DEL_INTERFACE_ADDR_REPLY);
+}
+
+static void *vl_api_nat64_add_del_interface_addr_t_print
+  (vl_api_nat64_add_del_interface_addr_t * mp, void *handle)
+{
+  u8 *s;
+
+  s = format (0, "SCRIPT: nat64_add_del_interface_addr ");
+  s = format (s, "sw_if_index %d %s",
+	      clib_host_to_net_u32 (mp->sw_if_index),
+	      mp->is_add ? "" : "del");
+
+  FINISH;
+}
+
 /***************/
 /*** DS-Lite ***/
 /***************/
@@ -3587,6 +3625,7 @@ _(NAT64_GET_TIMEOUTS, nat64_get_timeouts)                               \
 _(NAT64_ST_DUMP, nat64_st_dump)                                         \
 _(NAT64_ADD_DEL_PREFIX, nat64_add_del_prefix)                           \
 _(NAT64_PREFIX_DUMP, nat64_prefix_dump)                                 \
+_(NAT64_ADD_DEL_INTERFACE_ADDR, nat64_add_del_interface_addr)           \
 _(DSLITE_ADD_DEL_POOL_ADDR_RANGE, dslite_add_del_pool_addr_range)       \
 _(DSLITE_SET_AFTR_ADDR, dslite_set_aftr_addr)
 
diff --git a/test/test_nat.py b/test/test_nat.py
index 3c002bb8eca..76c52828ad9 100644
--- a/test/test_nat.py
+++ b/test/test_nat.py
@@ -3428,7 +3428,7 @@ class TestNAT64(MethodHolder):
             cls.vrf1_nat_addr_n = socket.inet_pton(socket.AF_INET,
                                                    cls.vrf1_nat_addr)
 
-            cls.create_pg_interfaces(range(4))
+            cls.create_pg_interfaces(range(5))
             cls.ip6_interfaces = list(cls.pg_interfaces[0:1])
             cls.ip6_interfaces.append(cls.pg_interfaces[2])
             cls.ip4_interfaces = list(cls.pg_interfaces[1:2])
@@ -4337,6 +4337,25 @@ class TestNAT64(MethodHolder):
         self.assertEqual(p[TCP].dport, self.tcp_port_in)
         self.assertEqual(data, p[Raw].load)
 
+    def test_interface_addr(self):
+        """ Acquire NAT64 pool addresses from interface """
+        self.vapi.nat64_add_interface_addr(self.pg4.sw_if_index)
+
+        # no address in NAT64 pool
+        adresses = self.vapi.nat44_address_dump()
+        self.assertEqual(0, len(adresses))
+
+        # configure interface address and check NAT64 address pool
+        self.pg4.config_ip4()
+        addresses = self.vapi.nat64_pool_addr_dump()
+        self.assertEqual(len(addresses), 1)
+        self.assertEqual(addresses[0].address, self.pg4.local_ip4n)
+
+        # remove interface address and check NAT64 address pool
+        self.pg4.unconfig_ip4()
+        addresses = self.vapi.nat64_pool_addr_dump()
+        self.assertEqual(0, len(adresses))
+
     def nat64_get_ses_num(self):
         """
         Return number of active NAT64 sessions.
diff --git a/test/vpp_papi_provider.py b/test/vpp_papi_provider.py
index 63f938376ae..495db95052e 100644
--- a/test/vpp_papi_provider.py
+++ b/test/vpp_papi_provider.py
@@ -1723,6 +1723,18 @@ class VppPapiProvider(object):
         """
         return self.api(self.papi.nat64_prefix_dump, {})
 
+    def nat64_add_interface_addr(
+            self,
+            sw_if_index,
+            is_add=1):
+        """Add/del NAT64 address from interface
+
+        :param sw_if_index: Software index of the interface
+        :param is_add: 1 if add, 0 if delete (Default value = 1)
+        """
+        return self.api(self.papi.nat64_add_del_interface_addr,
+                        {'is_add': is_add, 'sw_if_index': sw_if_index})
+
     def dslite_set_aftr_addr(self, ip6, ip4):
         """Set DS-Lite AFTR addresses