src/vnet/ip6-nd/rd_cp.c - fdio/vpp - Gitiles

 /*
  * Copyright (c) 2018 Cisco and/or its affiliates.
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include <vnet/ip6-nd/ip6_ra.h>

 #include <vnet/ip/ip6.h>
 #include <vnet/ip/ip6_link.h>
 #include <vnet/ethernet/ethernet.h>
 #include <vnet/fib/fib_table.h>
 #include <signal.h>
 #include <math.h>

 typedef struct
 {
   u32 sw_if_index;
   u8 address_length;
   ip6_address_t address;
   f64 due_time;
 } slaac_address_t;

 typedef struct
 {
   u32 sw_if_index;
   ip6_address_t router_address;
   f64 due_time;
 } default_route_t;

 typedef struct
 {
   u8 enabled;
   u8 install_default_routes;
 } interface_config_t;

 typedef struct
 {
   u8 enabled;
   u8 events_on;

   interface_config_t *config_by_sw_if_index;
   slaac_address_t *slaac_address_pool;
   default_route_t *default_route_pool;

   /* binary API client */
   u8 api_connected;
   u32 my_client_index;

   /* logging */
   vlib_log_class_t log_class;

   /* convenience */
   vlib_main_t *vlib_main;
   vnet_main_t *vnet_main;
   u32 node_index;
 } rd_cp_main_t;

 rd_cp_main_t rd_cp_main;

 enum
 {
   RD_CP_EVENT_INTERRUPT,
 };

 static void
 router_solicitation_start_stop (u32 sw_if_index, u8 start)
 {
   rd_cp_main_t *rm = &rd_cp_main;
   icmp6_send_router_solicitation_params_t params = { 0, };

   if (start)
     {
       params.irt = 1;
       params.mrt = 120;
     }

   icmp6_send_router_solicitation (rm->vlib_main, sw_if_index, !start,
 				  &params);
 }

 static void interrupt_process (void);

 static int
 add_slaac_address (vlib_main_t * vm, u32 sw_if_index, u8 address_length,
 		   const ip6_address_t * address, f64 due_time)
 {
   rd_cp_main_t *rm = &rd_cp_main;
   slaac_address_t *slaac_address;
   clib_error_t *rv = 0;

   pool_get_zero (rm->slaac_address_pool, slaac_address);

   slaac_address->sw_if_index = sw_if_index;
   slaac_address->address_length = address_length;
   slaac_address->address = *address;
   slaac_address->due_time = due_time;

   rv =
     ip6_add_del_interface_address (vm, sw_if_index, &slaac_address->address,
 				   address_length, 0);

   return rv != 0;
 }

 static void
 add_default_route (vlib_main_t * vm, u32 sw_if_index,
 		   const ip6_address_t * next_hop_address, f64 due_time)
 {
   rd_cp_main_t *rm = &rd_cp_main;
   default_route_t *default_route;

   pool_get_zero (rm->default_route_pool, default_route);

   default_route->sw_if_index = sw_if_index;
   default_route->router_address = *next_hop_address;
   default_route->due_time = due_time;

   {
     u32 fib_index = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP6,
 							 default_route->
 							 sw_if_index);
     fib_prefix_t pfx = {
       .fp_proto = FIB_PROTOCOL_IP6,
     };
     ip46_address_t nh = {
       .ip6 = default_route->router_address,
     };
     fib_table_entry_update_one_path (fib_index, &pfx,
 				     FIB_SOURCE_API,
 				     FIB_ENTRY_FLAG_NONE,
 				     DPO_PROTO_IP6,
 				     &nh,
 				     default_route->sw_if_index,
 				     0, 1, NULL, FIB_ROUTE_PATH_FLAG_NONE);
   }
 }

 static int
 remove_slaac_address (vlib_main_t * vm, slaac_address_t * slaac_address)
 {
   rd_cp_main_t *rm = &rd_cp_main;
   clib_error_t *rv = 0;

   rv = ip6_add_del_interface_address (vm, slaac_address->sw_if_index,
 				      &slaac_address->address,
 				      slaac_address->address_length, 1);

   pool_put (rm->slaac_address_pool, slaac_address);

   return rv != 0;
 }

 static void
 remove_default_route (vlib_main_t * vm, default_route_t * default_route)
 {
   rd_cp_main_t *rm = &rd_cp_main;

   {
     u32 fib_index = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP6,
 							 default_route->
 							 sw_if_index);
     fib_prefix_t pfx = {
       .fp_proto = FIB_PROTOCOL_IP6,
     };
     ip46_address_t nh = {
       .ip6 = default_route->router_address,
     };
     fib_table_entry_path_remove (fib_index, &pfx,
 				 FIB_SOURCE_API,
 				 DPO_PROTO_IP6,
 				 &nh,
 				 default_route->sw_if_index,
 				 0, 1, FIB_ROUTE_PATH_FLAG_NONE);
   }

   pool_put (rm->default_route_pool, default_route);
 }

 static u32
 get_interface_mac_address (u32 sw_if_index, u8 mac[])
 {
   rd_cp_main_t *rm = &rd_cp_main;
   vnet_sw_interface_t *si;
   ethernet_interface_t *eth_if = 0;

   if (!vnet_sw_interface_is_api_valid (rm->vnet_main, sw_if_index))
     {
       vlib_log_warn (rm->log_class, "Invalid sw_if_index");
       return 1;
     }

   si = vnet_get_sup_sw_interface (rm->vnet_main, sw_if_index);
   if (si->type == VNET_SW_INTERFACE_TYPE_HARDWARE)
     eth_if = ethernet_get_interface (&ethernet_main, si->hw_if_index);

   if (!eth_if)
     {
       vlib_log_warn (rm->log_class, "Failed to get hardware interface");
       return 1;
     }

   clib_memcpy_fast (mac, &eth_if->address, 6);

   return 0;
 }

 static u8
 ip6_prefixes_equal (ip6_address_t * prefix1, ip6_address_t * prefix2, u8 len)
 {
   if (len >= 64)
     {
       if (prefix1->as_u64[0] != prefix2->as_u64[0])
 	return 0;
       if (len == 64)
 	return 1;
       return prefix1->as_u64[1] >> (128 - len) ==
 	prefix2->as_u64[1] >> (128 - len);
     }
   return prefix1->as_u64[0] >> (64 - len) == prefix2->as_u64[0] >> (64 - len);
 }

 #define PREFIX_FLAG_A (1 << 6)
 #define PREFIX_FLAG_L (1 << 7)

 static void
 ip6_ra_report_handler (const ip6_ra_report_t * r)
 {
   rd_cp_main_t *rm = &rd_cp_main;
   vlib_main_t *vm = rm->vlib_main;
   interface_config_t *if_config;
   default_route_t *default_route;
   slaac_address_t *slaac_address;
   u32 sw_if_index;
   u16 router_lifetime_in_sec;
   u32 n_prefixes;
   ra_report_prefix_info_t *prefix;
   u8 mac[6];
   f64 current_time;
   u32 i;

   current_time = vlib_time_now (vm);

   sw_if_index = r->sw_if_index;

   if (sw_if_index >= vec_len (rm->config_by_sw_if_index))
     return;
   if_config = &rm->config_by_sw_if_index[sw_if_index];

   if (if_config->install_default_routes)
     {
       router_lifetime_in_sec = r->router_lifetime_in_sec;
       u8 route_already_present = 0;
       /* *INDENT-OFF* */
       pool_foreach (default_route, rm->default_route_pool)
        {
         if (default_route->sw_if_index != sw_if_index)
           ;
         else if (0 != memcmp (&default_route->router_address,
                               &r->router_address, 16))
           ;
         else
           {
             route_already_present = 1;
             goto default_route_pool_foreach_out;
           }
       }
       /* *INDENT-ON* */
     default_route_pool_foreach_out:

       if (!route_already_present)
 	{
 	  if (router_lifetime_in_sec != 0)
 	    add_default_route (vm, sw_if_index, &r->router_address,
 			       current_time + router_lifetime_in_sec);
 	}
       else
 	{
 	  if (router_lifetime_in_sec != 0)
 	    default_route->due_time = current_time + router_lifetime_in_sec;
 	  else
 	    remove_default_route (vm, default_route);
 	}
     }

   if (get_interface_mac_address (sw_if_index, mac) != 0)
     {
       vlib_log_warn (rm->log_class, "Error getting MAC address");
       return;
     }

   if (!if_config->enabled)
     return;

   n_prefixes = vec_len (r->prefixes);
   for (i = 0; i < n_prefixes; i++)
     {
       ip6_address_t *dst_address;
       u8 prefix_length;
       u32 valid_time;
       u32 preferred_time;
       f64 due_time;

       prefix = &r->prefixes[i];

       if (!(prefix->flags & PREFIX_FLAG_A))
 	continue;

       dst_address = &prefix->prefix.fp_addr.ip6;
       prefix_length = prefix->prefix.fp_len;

       if (ip6_address_is_link_local_unicast (dst_address))
 	continue;

       valid_time = prefix->valid_time;
       preferred_time = prefix->preferred_time;

       if (preferred_time > valid_time)
 	continue;

       if (prefix_length != 64)
 	continue;

       u8 address_already_present = 0;
       /* *INDENT-OFF* */
       pool_foreach (slaac_address, rm->slaac_address_pool)
        {
         if (slaac_address->sw_if_index != sw_if_index)
           ;
         else if (slaac_address->address_length != prefix_length)
           ;
         else if (!ip6_prefixes_equal (&slaac_address->address, dst_address,
                                  prefix_length))
           ;
         else
           {
             address_already_present = 1;
             goto slaac_address_pool_foreach_out;
           }
       }
       /* *INDENT-ON* */
     slaac_address_pool_foreach_out:

       if (address_already_present)
 	{
 	  f64 remaining_life_time = slaac_address->due_time - current_time;
 	  if (valid_time > 2 * 60 * 60 || valid_time > remaining_life_time)
 	    slaac_address->due_time = current_time + valid_time;
 	  else if (remaining_life_time > 2 * 60 * 60)
 	    slaac_address->due_time = current_time + 2 * 60 * 60;
 	  continue;
 	}

       if (valid_time == 0)
 	continue;

       due_time = current_time + valid_time;

       ip6_address_t addr;
       addr.as_u64[0] = dst_address->as_u64[0];
       /* Invert the "u" bit */
       addr.as_u8[8] = mac[0] ^ (1 << 1);
       addr.as_u8[9] = mac[1];
       addr.as_u8[10] = mac[2];
       addr.as_u8[11] = 0xFF;
       addr.as_u8[12] = 0xFE;
       addr.as_u8[13] = mac[3];
       addr.as_u8[14] = mac[4];
       addr.as_u8[15] = mac[5];

       add_slaac_address (vm, sw_if_index, prefix_length, &addr, due_time);
     }

   interrupt_process ();

   return;
 }

 static uword
 rd_cp_process (vlib_main_t * vm, vlib_node_runtime_t * rt, vlib_frame_t * f)
 {
   uword *event_data = 0;
   rd_cp_main_t *rm = &rd_cp_main;
   slaac_address_t *slaac_address;
   default_route_t *default_route;
   f64 sleep_time = 1e9;
   f64 current_time;
   f64 due_time;

   while (1)
     {
       vlib_process_wait_for_event_or_clock (vm, sleep_time);
       vlib_process_get_events (vm, &event_data);

       vec_reset_length (event_data);

       current_time = vlib_time_now (vm);
       do
 	{
 	  due_time = current_time + 1e9;
 	  u32 index;
 	  /*
 	   * we do not use pool_foreach() to iterate over pool elements here
 	   * as we are removing elements inside the loop body
 	   */
           /* *INDENT-OFF* */
           pool_foreach_index (index, rm->slaac_address_pool)
            {
             slaac_address = pool_elt_at_index(rm->slaac_address_pool, index);
             if (slaac_address->due_time > current_time)
               {
                 if (slaac_address->due_time < due_time)
                   due_time = slaac_address->due_time;
               }
             else
               {
                 u32 sw_if_index = slaac_address->sw_if_index;
                 remove_slaac_address (vm, slaac_address);
                 /* make sure ip6 stays enabled */
                 ip6_link_enable (sw_if_index, NULL);
               }
           }
           pool_foreach_index (index, rm->default_route_pool)
            {
             default_route = pool_elt_at_index(rm->default_route_pool, index);
             if (default_route->due_time > current_time)
               {
                 if (default_route->due_time < due_time)
                   due_time = default_route->due_time;
               }
             else
               remove_default_route (vm, default_route);
           }
           /* *INDENT-ON* */
 	  current_time = vlib_time_now (vm);
 	}
       while (due_time < current_time);

       sleep_time = due_time - current_time;
     }

   return 0;
 }

 /* *INDENT-OFF* */
 VLIB_REGISTER_NODE (rd_cp_process_node) = {
     .function = rd_cp_process,
     .type = VLIB_NODE_TYPE_PROCESS,
     .name = "rd-cp-process",
 };
 /* *INDENT-ON* */

 static void
 interrupt_process (void)
 {
   rd_cp_main_t *rm = &rd_cp_main;
   vlib_main_t *vm = rm->vlib_main;

   vlib_process_signal_event (vm, rd_cp_process_node.index,
 			     RD_CP_EVENT_INTERRUPT, 0);
 }

 int
 rd_cp_set_address_autoconfig (u32 sw_if_index,
 			      u8 enable, u8 install_default_routes)
 {
   rd_cp_main_t *rm = &rd_cp_main;
   vlib_main_t *vm = rm->vlib_main;
   vnet_main_t *vnm = rm->vnet_main;
   interface_config_t *if_config;
   interface_config_t empty_config = { 0, 0 };
   slaac_address_t *slaac_address;
   default_route_t *default_route;

   if (!enable)
     install_default_routes = 0;

   if (!vnet_sw_interface_is_api_valid (vnm, sw_if_index))
     {
       vlib_log_warn (rm->log_class, "Invalid sw_if_index");
       return 1;
     }

   if (!rm->enabled)
     {
       /* process kickoff */
       interrupt_process ();
       rm->enabled = 1;
     }

   vec_validate_init_empty (rm->config_by_sw_if_index, sw_if_index,
 			   empty_config);
   if_config = &rm->config_by_sw_if_index[sw_if_index];

   if (!if_config->enabled && enable)
     ip6_link_enable (sw_if_index, NULL);

   if ((!if_config->enabled && enable)
       || (!if_config->install_default_routes && install_default_routes))
     router_solicitation_start_stop (sw_if_index, 1);
   else if (if_config->enabled && !enable)
     router_solicitation_start_stop (sw_if_index, 0);

   if (if_config->enabled && !enable)
     {
       /* *INDENT-OFF* */
       pool_foreach (slaac_address, rm->slaac_address_pool)
        {
           remove_slaac_address (vm, slaac_address);
       }
       /* *INDENT-ON* */
     }
   if (if_config->install_default_routes && !install_default_routes)
     {
       /* *INDENT-OFF* */
       pool_foreach (default_route, rm->default_route_pool)
        {
           remove_default_route (vm, default_route);
       }
       /* *INDENT-ON* */
     }

   if_config->enabled = enable;
   if_config->install_default_routes = install_default_routes;

   return 0;
 }

 static clib_error_t *
 ip6_nd_address_autoconfig (vlib_main_t * vm,
 			   unformat_input_t * input, vlib_cli_command_t * cmd)
 {
   rd_cp_main_t *rm = &rd_cp_main;
   vnet_main_t *vnm = rm->vnet_main;
   clib_error_t *error = 0;
   u32 sw_if_index = ~0;
   u8 enable = 1;
   u8 default_route = 0;

   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
     {
       if (unformat
 	  (input, "%U", unformat_vnet_sw_interface, vnm, &sw_if_index))
 	;
       if (unformat (input, "default-route"))
 	default_route = 1;
       if (unformat (input, "disable"))
 	enable = 0;
       else
 	break;
     }

   if (sw_if_index != ~0)
     {
       if (rd_cp_set_address_autoconfig (sw_if_index, enable, default_route) !=
 	  0)
 	error = clib_error_return (0, "Invalid sw_if_index");
     }
   else
     error = clib_error_return (0, "Missing sw_if_index");

   return error;
 }

 /*?
  * This command is used to enable ND address autoconfiguration
  * on particular interface including setting up default routes.
  *
  * @cliexpar
  * @parblock
  * Example of how to enable ND address autoconfiguration:
  * @cliexcmd{ip6 nd address autoconfig GigabitEthernet2/0/0}
  * Example of how to enable ND address autoconfiguration
  * with setting up default routes:
  * @cliexcmd{ip6 nd address autoconfig GigabitEthernet2/0/0 default-route}
  * Example of how to disable ND address autoconfiguration:
  * @cliexcmd{ip6 nd address autoconfig GigabitEthernet2/0/0 disable}
  * @endparblock
 ?*/
 /* *INDENT-OFF* */
 VLIB_CLI_COMMAND (ip6_nd_address_autoconfig_command, static) = {
   .path = "ip6 nd address autoconfig",
   .short_help = "ip6 nd address autoconfig <interface> [default-route|disable]",
   .function = ip6_nd_address_autoconfig,
 };
 /* *INDENT-ON* */

 static clib_error_t *
 rd_cp_init (vlib_main_t * vm)
 {
   rd_cp_main_t *rm = &rd_cp_main;

   rm->vlib_main = vm;
   rm->vnet_main = vnet_get_main ();
   rm->node_index = rd_cp_process_node.index;

   rm->log_class = vlib_log_register_class ("rd_cp", 0);

   ip6_ra_report_register (ip6_ra_report_handler);

   return (NULL);
 }

 VLIB_INIT_FUNCTION (rd_cp_init);

 /*
  * fd.io coding-style-patch-verification: ON
  *
  * Local Variables:
  * eval: (c-set-style "gnu")
  * End:
  */
	/*
	* Copyright (c) 2018 Cisco and/or its affiliates.
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at:
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include <vnet/ip6-nd/ip6_ra.h>

	#include <vnet/ip/ip6.h>
	#include <vnet/ip/ip6_link.h>
	#include <vnet/ethernet/ethernet.h>
	#include <vnet/fib/fib_table.h>
	#include <signal.h>
	#include <math.h>

	typedef struct
	{
	u32 sw_if_index;
	u8 address_length;
	ip6_address_t address;
	f64 due_time;
	} slaac_address_t;

	typedef struct
	{
	u32 sw_if_index;
	ip6_address_t router_address;
	f64 due_time;
	} default_route_t;

	typedef struct
	{
	u8 enabled;
	u8 install_default_routes;
	} interface_config_t;

	typedef struct
	{
	u8 enabled;
	u8 events_on;

	interface_config_t *config_by_sw_if_index;
	slaac_address_t *slaac_address_pool;
	default_route_t *default_route_pool;

	/* binary API client */
	u8 api_connected;
	u32 my_client_index;

	/* logging */
	vlib_log_class_t log_class;

	/* convenience */
	vlib_main_t *vlib_main;
	vnet_main_t *vnet_main;
	u32 node_index;
	} rd_cp_main_t;

	rd_cp_main_t rd_cp_main;

	enum
	{
	RD_CP_EVENT_INTERRUPT,
	};

	static void
	router_solicitation_start_stop (u32 sw_if_index, u8 start)
	{
	rd_cp_main_t *rm = &rd_cp_main;
	icmp6_send_router_solicitation_params_t params = { 0, };

	if (start)
	{
	params.irt = 1;
	params.mrt = 120;
	}

	icmp6_send_router_solicitation (rm->vlib_main, sw_if_index, !start,
	&params);
	}

	static void interrupt_process (void);

	static int
	add_slaac_address (vlib_main_t * vm, u32 sw_if_index, u8 address_length,
	const ip6_address_t * address, f64 due_time)
	{
	rd_cp_main_t *rm = &rd_cp_main;
	slaac_address_t *slaac_address;
	clib_error_t *rv = 0;

	pool_get_zero (rm->slaac_address_pool, slaac_address);

	slaac_address->sw_if_index = sw_if_index;
	slaac_address->address_length = address_length;
	slaac_address->address = *address;
	slaac_address->due_time = due_time;

	rv =
	ip6_add_del_interface_address (vm, sw_if_index, &slaac_address->address,
	address_length, 0);

	return rv != 0;
	}

	static void
	add_default_route (vlib_main_t * vm, u32 sw_if_index,
	const ip6_address_t * next_hop_address, f64 due_time)
	{
	rd_cp_main_t *rm = &rd_cp_main;
	default_route_t *default_route;

	pool_get_zero (rm->default_route_pool, default_route);

	default_route->sw_if_index = sw_if_index;
	default_route->router_address = *next_hop_address;
	default_route->due_time = due_time;

	{
	u32 fib_index = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP6,
	default_route->
	sw_if_index);
	fib_prefix_t pfx = {
	.fp_proto = FIB_PROTOCOL_IP6,
	};
	ip46_address_t nh = {
	.ip6 = default_route->router_address,
	};
	fib_table_entry_update_one_path (fib_index, &pfx,
	FIB_SOURCE_API,
	FIB_ENTRY_FLAG_NONE,
	DPO_PROTO_IP6,
	&nh,
	default_route->sw_if_index,
	0, 1, NULL, FIB_ROUTE_PATH_FLAG_NONE);
	}
	}

	static int
	remove_slaac_address (vlib_main_t * vm, slaac_address_t * slaac_address)
	{
	rd_cp_main_t *rm = &rd_cp_main;
	clib_error_t *rv = 0;

	rv = ip6_add_del_interface_address (vm, slaac_address->sw_if_index,
	&slaac_address->address,
	slaac_address->address_length, 1);

	pool_put (rm->slaac_address_pool, slaac_address);

	return rv != 0;
	}

	static void
	remove_default_route (vlib_main_t * vm, default_route_t * default_route)
	{
	rd_cp_main_t *rm = &rd_cp_main;

	{
	u32 fib_index = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP6,
	default_route->
	sw_if_index);
	fib_prefix_t pfx = {
	.fp_proto = FIB_PROTOCOL_IP6,
	};
	ip46_address_t nh = {
	.ip6 = default_route->router_address,
	};
	fib_table_entry_path_remove (fib_index, &pfx,
	FIB_SOURCE_API,
	DPO_PROTO_IP6,
	&nh,
	default_route->sw_if_index,
	0, 1, FIB_ROUTE_PATH_FLAG_NONE);
	}

	pool_put (rm->default_route_pool, default_route);
	}

	static u32
	get_interface_mac_address (u32 sw_if_index, u8 mac[])
	{
	rd_cp_main_t *rm = &rd_cp_main;
	vnet_sw_interface_t *si;
	ethernet_interface_t *eth_if = 0;

	if (!vnet_sw_interface_is_api_valid (rm->vnet_main, sw_if_index))
	{
	vlib_log_warn (rm->log_class, "Invalid sw_if_index");
	return 1;
	}

	si = vnet_get_sup_sw_interface (rm->vnet_main, sw_if_index);
	if (si->type == VNET_SW_INTERFACE_TYPE_HARDWARE)
	eth_if = ethernet_get_interface (&ethernet_main, si->hw_if_index);

	if (!eth_if)
	{
	vlib_log_warn (rm->log_class, "Failed to get hardware interface");
	return 1;
	}

	clib_memcpy_fast (mac, &eth_if->address, 6);

	return 0;
	}

	static u8
	ip6_prefixes_equal (ip6_address_t * prefix1, ip6_address_t * prefix2, u8 len)
	{
	if (len >= 64)
	{
	if (prefix1->as_u64[0] != prefix2->as_u64[0])
	return 0;
	if (len == 64)
	return 1;
	return prefix1->as_u64[1] >> (128 - len) ==
	prefix2->as_u64[1] >> (128 - len);
	}
	return prefix1->as_u64[0] >> (64 - len) == prefix2->as_u64[0] >> (64 - len);
	}

	#define PREFIX_FLAG_A (1 << 6)
	#define PREFIX_FLAG_L (1 << 7)

	static void
	ip6_ra_report_handler (const ip6_ra_report_t * r)
	{
	rd_cp_main_t *rm = &rd_cp_main;
	vlib_main_t *vm = rm->vlib_main;
	interface_config_t *if_config;
	default_route_t *default_route;
	slaac_address_t *slaac_address;
	u32 sw_if_index;
	u16 router_lifetime_in_sec;
	u32 n_prefixes;
	ra_report_prefix_info_t *prefix;
	u8 mac[6];
	f64 current_time;
	u32 i;

	current_time = vlib_time_now (vm);

	sw_if_index = r->sw_if_index;

	if (sw_if_index >= vec_len (rm->config_by_sw_if_index))
	return;
	if_config = &rm->config_by_sw_if_index[sw_if_index];

	if (if_config->install_default_routes)
	{
	router_lifetime_in_sec = r->router_lifetime_in_sec;
	u8 route_already_present = 0;
	/* INDENT-OFF */
	pool_foreach (default_route, rm->default_route_pool)
	{
	if (default_route->sw_if_index != sw_if_index)
	;
	else if (0 != memcmp (&default_route->router_address,
	&r->router_address, 16))
	;
	else
	{
	route_already_present = 1;
	goto default_route_pool_foreach_out;
	}
	}
	/* INDENT-ON */
	default_route_pool_foreach_out:

	if (!route_already_present)
	{
	if (router_lifetime_in_sec != 0)
	add_default_route (vm, sw_if_index, &r->router_address,
	current_time + router_lifetime_in_sec);
	}
	else
	{
	if (router_lifetime_in_sec != 0)
	default_route->due_time = current_time + router_lifetime_in_sec;
	else
	remove_default_route (vm, default_route);
	}
	}

	if (get_interface_mac_address (sw_if_index, mac) != 0)
	{
	vlib_log_warn (rm->log_class, "Error getting MAC address");
	return;
	}

	if (!if_config->enabled)
	return;

	n_prefixes = vec_len (r->prefixes);
	for (i = 0; i < n_prefixes; i++)
	{
	ip6_address_t *dst_address;
	u8 prefix_length;
	u32 valid_time;
	u32 preferred_time;
	f64 due_time;

	prefix = &r->prefixes[i];

	if (!(prefix->flags & PREFIX_FLAG_A))
	continue;

	dst_address = &prefix->prefix.fp_addr.ip6;
	prefix_length = prefix->prefix.fp_len;

	if (ip6_address_is_link_local_unicast (dst_address))
	continue;

	valid_time = prefix->valid_time;
	preferred_time = prefix->preferred_time;

	if (preferred_time > valid_time)
	continue;

	if (prefix_length != 64)
	continue;

	u8 address_already_present = 0;
	/* INDENT-OFF */
	pool_foreach (slaac_address, rm->slaac_address_pool)
	{
	if (slaac_address->sw_if_index != sw_if_index)
	;
	else if (slaac_address->address_length != prefix_length)
	;
	else if (!ip6_prefixes_equal (&slaac_address->address, dst_address,
	prefix_length))
	;
	else
	{
	address_already_present = 1;
	goto slaac_address_pool_foreach_out;
	}
	}
	/* INDENT-ON */
	slaac_address_pool_foreach_out:

	if (address_already_present)
	{
	f64 remaining_life_time = slaac_address->due_time - current_time;
	if (valid_time > 2 * 60 * 60 \|\| valid_time > remaining_life_time)
	slaac_address->due_time = current_time + valid_time;
	else if (remaining_life_time > 2 * 60 * 60)
	slaac_address->due_time = current_time + 2 * 60 * 60;
	continue;
	}

	if (valid_time == 0)
	continue;

	due_time = current_time + valid_time;

	ip6_address_t addr;
	addr.as_u64[0] = dst_address->as_u64[0];
	/* Invert the "u" bit */
	addr.as_u8[8] = mac[0] ^ (1 << 1);
	addr.as_u8[9] = mac[1];
	addr.as_u8[10] = mac[2];
	addr.as_u8[11] = 0xFF;
	addr.as_u8[12] = 0xFE;
	addr.as_u8[13] = mac[3];
	addr.as_u8[14] = mac[4];
	addr.as_u8[15] = mac[5];

	add_slaac_address (vm, sw_if_index, prefix_length, &addr, due_time);
	}

	interrupt_process ();

	return;
	}

	static uword
	rd_cp_process (vlib_main_t * vm, vlib_node_runtime_t * rt, vlib_frame_t * f)
	{
	uword *event_data = 0;
	rd_cp_main_t *rm = &rd_cp_main;
	slaac_address_t *slaac_address;
	default_route_t *default_route;
	f64 sleep_time = 1e9;
	f64 current_time;
	f64 due_time;

	while (1)
	{
	vlib_process_wait_for_event_or_clock (vm, sleep_time);
	vlib_process_get_events (vm, &event_data);

	vec_reset_length (event_data);

	current_time = vlib_time_now (vm);
	do
	{
	due_time = current_time + 1e9;
	u32 index;
	/*
	* we do not use pool_foreach() to iterate over pool elements here
	* as we are removing elements inside the loop body
	*/
	/* INDENT-OFF */
	pool_foreach_index (index, rm->slaac_address_pool)
	{
	slaac_address = pool_elt_at_index(rm->slaac_address_pool, index);
	if (slaac_address->due_time > current_time)
	{
	if (slaac_address->due_time < due_time)
	due_time = slaac_address->due_time;
	}
	else
	{
	u32 sw_if_index = slaac_address->sw_if_index;
	remove_slaac_address (vm, slaac_address);
	/* make sure ip6 stays enabled */
	ip6_link_enable (sw_if_index, NULL);
	}
	}
	pool_foreach_index (index, rm->default_route_pool)
	{
	default_route = pool_elt_at_index(rm->default_route_pool, index);
	if (default_route->due_time > current_time)
	{
	if (default_route->due_time < due_time)
	due_time = default_route->due_time;
	}
	else
	remove_default_route (vm, default_route);
	}
	/* INDENT-ON */
	current_time = vlib_time_now (vm);
	}
	while (due_time < current_time);

	sleep_time = due_time - current_time;
	}

	return 0;
	}

	/* INDENT-OFF */
	VLIB_REGISTER_NODE (rd_cp_process_node) = {
	.function = rd_cp_process,
	.type = VLIB_NODE_TYPE_PROCESS,
	.name = "rd-cp-process",
	};
	/* INDENT-ON */

	static void
	interrupt_process (void)
	{
	rd_cp_main_t *rm = &rd_cp_main;
	vlib_main_t *vm = rm->vlib_main;

	vlib_process_signal_event (vm, rd_cp_process_node.index,
	RD_CP_EVENT_INTERRUPT, 0);
	}

	int
	rd_cp_set_address_autoconfig (u32 sw_if_index,
	u8 enable, u8 install_default_routes)
	{
	rd_cp_main_t *rm = &rd_cp_main;
	vlib_main_t *vm = rm->vlib_main;
	vnet_main_t *vnm = rm->vnet_main;
	interface_config_t *if_config;
	interface_config_t empty_config = { 0, 0 };
	slaac_address_t *slaac_address;
	default_route_t *default_route;

	if (!enable)
	install_default_routes = 0;

	if (!vnet_sw_interface_is_api_valid (vnm, sw_if_index))
	{
	vlib_log_warn (rm->log_class, "Invalid sw_if_index");
	return 1;
	}

	if (!rm->enabled)
	{
	/* process kickoff */
	interrupt_process ();
	rm->enabled = 1;
	}

	vec_validate_init_empty (rm->config_by_sw_if_index, sw_if_index,
	empty_config);
	if_config = &rm->config_by_sw_if_index[sw_if_index];

	if (!if_config->enabled && enable)
	ip6_link_enable (sw_if_index, NULL);

	if ((!if_config->enabled && enable)
	\|\| (!if_config->install_default_routes && install_default_routes))
	router_solicitation_start_stop (sw_if_index, 1);
	else if (if_config->enabled && !enable)
	router_solicitation_start_stop (sw_if_index, 0);

	if (if_config->enabled && !enable)
	{
	/* INDENT-OFF */
	pool_foreach (slaac_address, rm->slaac_address_pool)
	{
	remove_slaac_address (vm, slaac_address);
	}
	/* INDENT-ON */
	}
	if (if_config->install_default_routes && !install_default_routes)
	{
	/* INDENT-OFF */
	pool_foreach (default_route, rm->default_route_pool)
	{
	remove_default_route (vm, default_route);
	}
	/* INDENT-ON */
	}

	if_config->enabled = enable;
	if_config->install_default_routes = install_default_routes;

	return 0;
	}

	static clib_error_t *
	ip6_nd_address_autoconfig (vlib_main_t * vm,
	unformat_input_t * input, vlib_cli_command_t * cmd)
	{
	rd_cp_main_t *rm = &rd_cp_main;
	vnet_main_t *vnm = rm->vnet_main;
	clib_error_t *error = 0;
	u32 sw_if_index = ~0;
	u8 enable = 1;
	u8 default_route = 0;

	while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
	{
	if (unformat
	(input, "%U", unformat_vnet_sw_interface, vnm, &sw_if_index))
	;
	if (unformat (input, "default-route"))
	default_route = 1;
	if (unformat (input, "disable"))
	enable = 0;
	else
	break;
	}

	if (sw_if_index != ~0)
	{
	if (rd_cp_set_address_autoconfig (sw_if_index, enable, default_route) !=
	0)
	error = clib_error_return (0, "Invalid sw_if_index");
	}
	else
	error = clib_error_return (0, "Missing sw_if_index");

	return error;
	}

	/*?
	* This command is used to enable ND address autoconfiguration
	* on particular interface including setting up default routes.
	*
	* @cliexpar
	* @parblock
	* Example of how to enable ND address autoconfiguration:
	* @cliexcmd{ip6 nd address autoconfig GigabitEthernet2/0/0}
	* Example of how to enable ND address autoconfiguration
	* with setting up default routes:
	* @cliexcmd{ip6 nd address autoconfig GigabitEthernet2/0/0 default-route}
	* Example of how to disable ND address autoconfiguration:
	* @cliexcmd{ip6 nd address autoconfig GigabitEthernet2/0/0 disable}
	* @endparblock
	?*/
	/* INDENT-OFF */
	VLIB_CLI_COMMAND (ip6_nd_address_autoconfig_command, static) = {
	.path = "ip6 nd address autoconfig",
	.short_help = "ip6 nd address autoconfig <interface> [default-route\|disable]",
	.function = ip6_nd_address_autoconfig,
	};
	/* INDENT-ON */

	static clib_error_t *
	rd_cp_init (vlib_main_t * vm)
	{
	rd_cp_main_t *rm = &rd_cp_main;

	rm->vlib_main = vm;
	rm->vnet_main = vnet_get_main ();
	rm->node_index = rd_cp_process_node.index;

	rm->log_class = vlib_log_register_class ("rd_cp", 0);

	ip6_ra_report_register (ip6_ra_report_handler);

	return (NULL);
	}

	VLIB_INIT_FUNCTION (rd_cp_init);

	/*
	* fd.io coding-style-patch-verification: ON
	*
	* Local Variables:
	* eval: (c-set-style "gnu")
	* End:
	*/