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  1. /*
  2.  * Copyright (c) 2009 Lukas Mejdrech
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup arp
  30.  *  @{
  31.  */
  32.  
  33. /** @file
  34.  *  ARP module implementation.
  35.  *  @see arp.h
  36.  */
  37.  
  38. #include <async.h>
  39. #include <malloc.h>
  40. #include <mem.h>
  41. #include <rwlock.h>
  42. #include <stdio.h>
  43. #include <string.h>
  44. #include <task.h>
  45.  
  46. #include <ipc/ipc.h>
  47. #include <ipc/services.h>
  48.  
  49. #include "../../err.h"
  50. #include "../../messages.h"
  51. #include "../../modules.h"
  52.  
  53. #include "../../include/byteorder.h"
  54. #include "../../include/device.h"
  55. #include "../../include/arp_interface.h"
  56. #include "../../include/nil_interface.h"
  57. #include "../../include/protocol_map.h"
  58.  
  59. #include "../../structures/measured_strings.h"
  60. #include "../../structures/packet/packet.h"
  61. #include "../../structures/packet/packet_client.h"
  62.  
  63. #include "../il_messages.h"
  64.  
  65. #include "arp.h"
  66. #include "arp_header.h"
  67. #include "arp_oc.h"
  68. #include "arp_module.h"
  69. #include "arp_messages.h"
  70.  
  71. /** ARP global data.
  72.  */
  73. arp_globals_t   arp_globals;
  74.  
  75. /** Clears the whole cache.
  76.  *  @returns EOK on success.
  77.  */
  78. int arp_clean_cache_req( int arp_phone );
  79.  
  80. /** Clears the device specific data from the cache.
  81.  *  @param arp_phone The ARP module phone used for (semi)remote calls. Input parameter.
  82.  *  @param device_id The device identifier. Input parameter.
  83.  *  @returns EOK on success.
  84.  *  @returns ENOENT  if the device is not found in the cache.
  85.  */
  86. int arp_clear_device_req( int arp_phone, device_id_t device_id );
  87.  
  88. /** Creates new protocol specific data.
  89.  *  @param proto Protocol specific data. Output parameter.
  90.  *  @param service Protocol module service. Input parameter.
  91.  *  @param address Actual protocol device address. Input parameter.
  92.  *  @returns EOK on success.
  93.  *  @returns ENOMEM if there is not enough memory left.
  94.  */
  95. int arp_proto_create( arp_proto_ref * proto, services_t service, measured_string_ref address );
  96.  
  97. /** Registers the device.
  98.  *  Creates new device entry in the cache or updates the protocol address if the device with the device identifier and the driver service exists.
  99.  *  @param device_id The device identifier. Input parameter.
  100.  *  @param service The device driver service. Input parameter.
  101.  *  @param protocol The protocol service. Input parameter.
  102.  *  @param address The actual device protocol address.
  103.  *  @returns EOK on success.
  104.  *  @returns EEXIST if another device with the same device identifier and different driver service exists.
  105.  *  @returns ENOMEM if there is not enough memory left.
  106.  *  @returns Other error codes as defined for the measured_strings_return() function.
  107.  */
  108. int arp_device_message( device_id_t device_id, services_t service, services_t protocol, measured_string_ref address );
  109.  
  110. /** Returns the hardware address for the given protocol address.
  111.  *  Sends the ARP request packet if the hardware address is not found in the cache.
  112.  *  @param device_id The device identifier. Input parameter.
  113.  *  @param protocol The protocol service. Input parameter.
  114.  *  @param target The target protocol address. Input parameter.
  115.  *  @returns The hardware address of the target.
  116.  *  @returns NULL if the target parameter is NULL.
  117.  *  @returns NULL if the device is not found.
  118.  *  @returns NULL if the device packet is too small to send a&nbsp;request.
  119.  *  @returns NULL if the hardware address is not found in the cache.
  120.  */
  121. measured_string_ref arp_translate_message( device_id_t device_id, services_t protocol, measured_string_ref target );
  122.  
  123. /** Processes the received ARP packet.
  124.  *  Updates the source hardware address if the source entry exists or the packet is targeted to my protocol address.
  125.  *  Responses to the ARP request if the packet is the ARP request and is targeted to my address.
  126.  *  @param device_id The source device identifier. Input parameter.
  127.  *  @param packet The received packet. Input/output parameter.
  128.  *  @returns EOK on success.
  129.  *  @returns EINVAL if the packet is too small to carry the ARP packet.
  130.  *  @returns EINVAL if the received address lengths differs from the registered values.
  131.  *  @returns ENOENT if the device is not found in the cache.
  132.  *  @returns ENOENT if the protocol for the device is not found in the cache.
  133.  *  @returns ENOMEM if there is not enough memory left.
  134.  */
  135. int arp_receive_message( device_id_t device_id, packet_t packet );
  136.  
  137. /** Clears the device specific data.
  138.  *  @param device The device specific data.
  139.  */
  140. void    clear_device( arp_device_ref device );
  141.  
  142. /** Processes IPC messages from the registered device driver modules in an infinite loop.
  143.  *  @param iid The message identifier. Input parameter.
  144.  *  @param icall The message parameters. Input/output parameter.
  145.  */
  146. void    arp_receiver( ipc_callid_t iid, ipc_call_t * icall );
  147.  
  148. DEVICE_MAP_IMPLEMENT( arp_cache, arp_device_t )
  149.  
  150. INT_MAP_IMPLEMENT( arp_protos, arp_proto_t )
  151.  
  152. GENERIC_CHAR_MAP_IMPLEMENT( arp_addr, measured_string_t )
  153.  
  154. int arp_task_get_id( void ){
  155.     return task_get_id();
  156. }
  157.  
  158. int arp_clear_device_req( int arp_phone, device_id_t device_id ){
  159.     arp_device_ref  device;
  160.  
  161.     rwlock_write_lock( & arp_globals.lock );
  162.     device = arp_cache_find( & arp_globals.cache, device_id );
  163.     if( ! device ){
  164.         rwlock_write_unlock( & arp_globals.lock );
  165.         return ENOENT;
  166.     }
  167.     clear_device( device );
  168.     printf( "Device %d cleared\n", device_id );
  169.     rwlock_write_unlock( & arp_globals.lock );
  170.     return EOK;
  171. }
  172.  
  173. int arp_clean_cache_req( int arp_phone ){
  174.     int             count;
  175.     arp_device_ref  device;
  176.  
  177.     rwlock_write_lock( & arp_globals.lock );
  178.     for( count = arp_cache_count( & arp_globals.cache ) - 1; count >= 0; -- count ){
  179.         device = arp_cache_get_index( & arp_globals.cache, count );
  180.         if( device ){
  181.             clear_device( device );
  182.             if( device->addr_data ) free( device->addr_data );
  183.             if( device->broadcast_data ) free( device->broadcast_data );
  184.         }
  185.     }
  186.     arp_cache_clear( & arp_globals.cache );
  187.     rwlock_write_unlock( & arp_globals.lock );
  188.     printf( "Cache cleaned\n" );
  189.     return EOK;
  190. }
  191.  
  192. int arp_device_req( int arp_phone, device_id_t device_id, services_t protocol, services_t netif, measured_string_ref address ){
  193.     ERROR_DECLARE;
  194.  
  195.     measured_string_ref tmp;
  196.  
  197.     tmp = measured_string_copy( address );
  198.     if( ERROR_OCCURRED( arp_device_message( device_id, netif, protocol, tmp ))){
  199.         free( tmp->value );
  200.         free( tmp );
  201.     }
  202.     return ERROR_CODE;
  203. }
  204.  
  205. int arp_translate_req( int arp_phone, device_id_t device_id, services_t protocol, measured_string_ref address, measured_string_ref * translation, char ** data ){
  206.     measured_string_ref tmp;
  207.  
  208.     rwlock_read_lock( & arp_globals.lock );
  209.     tmp = arp_translate_message( device_id, protocol, address );
  210.     if( tmp ){
  211.         * translation = measured_string_copy( tmp );
  212.         rwlock_read_unlock( & arp_globals.lock );
  213.         if( * translation ){
  214.             * data = ( ** translation ).value;
  215.             return EOK;
  216.         }else{
  217.             return ENOMEM;
  218.         }
  219.     }else{
  220.         rwlock_read_unlock( & arp_globals.lock );
  221.         return ENOENT;
  222.     }
  223. }
  224.  
  225. int arp_initialize( void ){
  226.     ERROR_DECLARE;
  227.  
  228.     rwlock_initialize( & arp_globals.lock );
  229.     rwlock_write_lock( & arp_globals.lock );
  230.     ERROR_PROPAGATE( arp_cache_initialize( & arp_globals.cache ));
  231.     rwlock_write_unlock( & arp_globals.lock );
  232.     return EOK;
  233. }
  234.  
  235. int arp_proto_create( arp_proto_ref * proto, services_t service, measured_string_ref address ){
  236.     ERROR_DECLARE;
  237.  
  238.     * proto = ( arp_proto_ref ) malloc( sizeof( arp_proto_t ));
  239.     if( !( * proto )) return ENOMEM;
  240.     ( ** proto ).service = service;
  241.     ( ** proto ).addr = address;
  242.     ( ** proto ).addr_data = address->value;
  243.     if( ERROR_OCCURRED( arp_addr_initialize( &( ** proto).addresses ))){
  244.         free( * proto );
  245.         return ERROR_CODE;
  246.     }
  247.     return EOK;
  248. }
  249.  
  250. int arp_device_message( device_id_t device_id, services_t service, services_t protocol, measured_string_ref address ){
  251.     ERROR_DECLARE;
  252.  
  253.     arp_device_ref  device;
  254.     arp_proto_ref   proto;
  255.     int             index;
  256.  
  257.     rwlock_write_lock( & arp_globals.lock );
  258.     // an existing device?
  259.     device = arp_cache_find( & arp_globals.cache, device_id );
  260.     if( device ){
  261.         if( device->service != service ){
  262.             printf( "Device %d already exists\n", device->device_id );
  263.             rwlock_write_unlock( & arp_globals.lock );
  264.             return EEXIST;
  265.         }
  266.         proto = arp_protos_find( & device->protos, protocol );
  267.         if( proto ){
  268.             free( proto->addr );
  269.             free( proto->addr_data );
  270.             proto->addr = address;
  271.             proto->addr_data = address->value;
  272.         }else{
  273.             if( ERROR_OCCURRED( arp_proto_create( & proto, protocol, address ))){
  274.                 rwlock_write_unlock( & arp_globals.lock );
  275.                 return ERROR_CODE;
  276.             }
  277.             index = arp_protos_add( & device->protos, proto->service, proto );
  278.             if( index < 0 ){
  279.                 rwlock_write_unlock( & arp_globals.lock );
  280.                 free( proto );
  281.                 return index;
  282.             }
  283.             printf( "New protocol added:\n\tdevice id\t= %d\n\tproto\t= %d", device_id, protocol );
  284.         }
  285.     }else{
  286.         index = hardware_map( service );
  287.         if( ! index ) return ENOENT;
  288.         // create a new device
  289.         device = ( arp_device_ref ) malloc( sizeof( arp_device_t ));
  290.         if( ! device ){
  291.             rwlock_write_unlock( & arp_globals.lock );
  292.             return ENOMEM;
  293.         }
  294.         device->hardware = index;
  295.         device->device_id = device_id;
  296.         if( ERROR_OCCURRED( arp_protos_initialize( & device->protos ))
  297.         || ERROR_OCCURRED( arp_proto_create( & proto, protocol, address ))){
  298.             rwlock_write_unlock( & arp_globals.lock );
  299.             free( device );
  300.             return ERROR_CODE;
  301.         }
  302.         index = arp_protos_add( & device->protos, proto->service, proto );
  303.         if( index < 0 ){
  304.             rwlock_write_unlock( & arp_globals.lock );
  305.             arp_protos_destroy( & device->protos );
  306.             free( device );
  307.             return index;
  308.         }
  309.         device->service = service;
  310.         // bind the new one
  311.         device->phone = bind_service( device->service, device->device_id, SERVICE_ARP, 0, arp_receiver );
  312.         if( device->phone < 0 ){
  313.             rwlock_write_unlock( & arp_globals.lock );
  314.             arp_protos_destroy( & device->protos );
  315.             free( device );
  316.             return EREFUSED;
  317.         }
  318.         // get packet dimensions
  319.         if( ERROR_OCCURRED( nil_packet_size_req( device->phone, device_id, & device->addr_len, & device->prefix, & device->content, & device->suffix ))){
  320.             rwlock_write_unlock( & arp_globals.lock );
  321.             arp_protos_destroy( & device->protos );
  322.             free( device );
  323.             return ERROR_CODE;
  324.         }
  325.         // get hardware address
  326.         if( ERROR_OCCURRED( nil_get_addr( device->phone, device_id, & device->addr, & device->addr_data ))){
  327.             rwlock_write_unlock( & arp_globals.lock );
  328.             arp_protos_destroy( & device->protos );
  329.             free( device );
  330.             return ERROR_CODE;
  331.         }
  332.         // get broadcast address
  333.         if( ERROR_OCCURRED( nil_get_broadcast_addr( device->phone, device_id, & device->broadcast_addr, & device->broadcast_data ))){
  334.             rwlock_write_unlock( & arp_globals.lock );
  335.             free( device->addr );
  336.             free( device->addr_data );
  337.             arp_protos_destroy( & device->protos );
  338.             free( device );
  339.             return ERROR_CODE;
  340.         }
  341.         if( ERROR_OCCURRED( arp_cache_add( & arp_globals.cache, device->device_id, device ))){
  342.             rwlock_write_unlock( & arp_globals.lock );
  343.             free( device->addr );
  344.             free( device->addr_data );
  345.             free( device->broadcast_addr );
  346.             free( device->broadcast_data );
  347.             arp_protos_destroy( & device->protos );
  348.             free( device );
  349.             return ERROR_CODE;
  350.         }
  351.         printf( "New device registered:\n\tid\t= %d\n\ttype\t= 0x%x\n\tservice\t= %d\n\tproto\t= %d\n", device->device_id, device->hardware, device->service, protocol );
  352.     }
  353.     rwlock_write_unlock( & arp_globals.lock );
  354.     return EOK;
  355. }
  356.  
  357. measured_string_ref arp_translate_message( device_id_t device_id, services_t protocol, measured_string_ref target ){
  358.     arp_device_ref      device;
  359.     arp_proto_ref       proto;
  360.     measured_string_ref addr;
  361.     size_t              length;
  362.     packet_t            packet;
  363.     arp_header_ref      header;
  364.  
  365.     if( ! target ) return NULL;
  366.     device = arp_cache_find( & arp_globals.cache, device_id );
  367.     if( ! device ) return NULL;
  368.     proto = arp_protos_find( & device->protos, protocol );
  369.     if(( ! proto ) || ( proto->addr->length != target->length )) return NULL;
  370.     addr = arp_addr_find( & proto->addresses, target->value, target->length );
  371.     if( addr ) return addr;
  372.     // ARP packet content size = header + ( address + translation ) * 2
  373.     length = 8 + ( CONVERT_SIZE( char, uint8_t, proto->addr->length ) + CONVERT_SIZE( char, uint8_t, device->addr->length )) * 2;
  374.     if( length > device->content ) return NULL;
  375.     packet = packet_get_4( arp_globals.net_phone, device->addr_len, device->prefix, length, device->suffix );
  376.     if( ! packet ) return NULL;
  377.     header = ( arp_header_ref ) packet_suffix( packet, length );
  378.     header->hardware = htons( device->hardware );
  379.     header->hardware_length = device->addr->length;
  380.     header->protocol = htons( protocol_map( device->service, protocol ));
  381.     header->protocol_length = proto->addr->length;
  382.     header->operation = htons( ARPOP_REQUEST );
  383.     length = sizeof( arp_header_t );
  384.     memcpy((( uint8_t * ) header ) + length, device->addr->value, device->addr->length );
  385.     length += device->addr->length;
  386.     memcpy((( uint8_t * ) header ) + length, proto->addr->value, proto->addr->length );
  387.     length += proto->addr->length;
  388.     bzero((( uint8_t * ) header ) + length, device->addr->length );
  389.     length += device->addr->length;
  390.     memcpy((( uint8_t * ) header ) + length, target->value, target->length );
  391.     packet_set_addr( packet, ( uint8_t * ) device->addr->value, ( uint8_t * ) device->broadcast_addr->value, CONVERT_SIZE( char, uint8_t, device->addr->length ));
  392.     nil_send_msg( device->phone, device_id, packet, SERVICE_ARP );
  393.     return NULL;
  394. }
  395.  
  396. int arp_receive_message( device_id_t device_id, packet_t packet ){
  397.     ERROR_DECLARE;
  398.  
  399.     size_t              length;
  400.     arp_header_ref      header;
  401.     arp_device_ref      device;
  402.     arp_proto_ref       proto;
  403.     measured_string_ref hw_source;
  404.     uint8_t *           src_hw;
  405.     uint8_t *           src_proto;
  406.     uint8_t *           des_hw;
  407.     uint8_t *           des_proto;
  408.  
  409.     length = packet_get_data_length( packet );
  410.     if( length <= sizeof( arp_header_t )) return EINVAL;
  411.     device = arp_cache_find( & arp_globals.cache, device_id );
  412.     if( ! device ) return ENOENT;
  413.     header = ( arp_header_ref ) packet_get_data( packet );
  414.     if(( ntohs( header->hardware ) != device->hardware )
  415.     || ( length < sizeof( arp_header_t ) + ( header->hardware_length + header->protocol_length ) * 2 )){
  416.         return EINVAL;
  417.     }
  418.     proto = arp_protos_find( & device->protos, protocol_unmap( device->service, ntohs( header->protocol )));
  419.     if( ! proto ) return ENOENT;
  420.     src_hw = (( uint8_t * ) header ) + sizeof( arp_header_t );
  421.     src_proto = src_hw + header->hardware_length;
  422.     des_hw = src_proto + header->protocol_length;
  423.     des_proto = des_hw + header->hardware_length;
  424.     hw_source = arp_addr_find( & proto->addresses, ( char * ) src_proto, CONVERT_SIZE( uint8_t, char, header->protocol_length ));
  425.     // exists?
  426.     if( hw_source ){
  427.         if( hw_source->length != CONVERT_SIZE( uint8_t, char, header->hardware_length )){
  428.             return EINVAL;
  429.         }
  430.         memcpy( hw_source->value, src_hw, hw_source->length );
  431.     }
  432.     // is my protocol address?
  433.     if( proto->addr->length != CONVERT_SIZE( uint8_t, char, header->protocol_length )){
  434.         return EINVAL;
  435.     }
  436.     if( ! str_lcmp( proto->addr->value, ( char * ) des_proto, proto->addr->length )){
  437.         // not already upadted?
  438.         if( ! hw_source ){
  439.             hw_source = measured_string_create_bulk(( char * ) src_hw, CONVERT_SIZE( uint8_t, char, header->hardware_length ));
  440.             if( ! hw_source ) return ENOMEM;
  441.             ERROR_PROPAGATE( arp_addr_add( & proto->addresses, ( char * ) src_proto, CONVERT_SIZE( uint8_t, char, header->protocol_length ), hw_source ));
  442.         }
  443.         if( ntohs( header->operation ) == ARPOP_REQUEST ){
  444.             header->operation = htons( ARPOP_REPLY );
  445.             memcpy( des_proto, src_proto, header->protocol_length );
  446.             memcpy( src_proto, proto->addr->value, header->protocol_length );
  447.             memcpy( src_hw, device->addr->value, device->addr_len );
  448.             memcpy( des_hw, hw_source->value, header->hardware_length );
  449.             packet_set_addr( packet, src_hw, des_hw, header->hardware_length );
  450.             nil_send_msg( device->phone, device_id, packet, SERVICE_ARP );
  451.         }else{
  452.             pq_release( arp_globals.net_phone, packet_get_id( packet ));
  453.         }
  454.     }
  455.     return EOK;
  456. }
  457.  
  458. void clear_device( arp_device_ref device ){
  459.     int             count;
  460.     arp_proto_ref   proto;
  461.  
  462.     for( count = arp_protos_count( & device->protos ) - 1; count >= 0; -- count ){
  463.         proto = arp_protos_get_index( & device->protos, count );
  464.         if( proto ){
  465.             if( proto->addr ) free( proto->addr );
  466.             if( proto->addr_data ) free( proto->addr_data );
  467.             arp_addr_destroy( & proto->addresses );
  468.         }
  469.     }
  470.     arp_protos_clear( & device->protos );
  471. }
  472.  
  473. int arp_connect_module( services_t service ){
  474.     return EOK;
  475. }
  476.  
  477. int arp_message( ipc_callid_t callid, ipc_call_t * call, ipc_call_t * answer, int * answer_count ){
  478.     ERROR_DECLARE;
  479.  
  480.     measured_string_ref address;
  481.     measured_string_ref translation;
  482.     char *              data;
  483.  
  484. //  printf( "message %d - %d\n", IPC_GET_METHOD( * call ), NET_ARP_FIRST );
  485.     * answer_count = 0;
  486.     switch( IPC_GET_METHOD( * call )){
  487.         case IPC_M_PHONE_HUNGUP:
  488.             return EOK;
  489.         case NET_ARP_DEVICE:
  490.             ERROR_PROPAGATE( measured_strings_receive( & address, & data, 1 ));
  491.             if( ERROR_OCCURRED( arp_device_message( IPC_GET_DEVICE( call ), IPC_GET_SERVICE( call ), ARP_GET_NETIF( call ), address ))){
  492.                 free( address );
  493.                 free( data );
  494.             }
  495.             return ERROR_CODE;
  496.         case NET_ARP_TRANSLATE:
  497.             ERROR_PROPAGATE( measured_strings_receive( & address, & data, 1 ));
  498.             rwlock_read_lock( & arp_globals.lock );
  499.             translation = arp_translate_message( IPC_GET_DEVICE( call ), IPC_GET_SERVICE( call ), address );
  500.             free( address );
  501.             free( data );
  502.             if( ! translation ){
  503.                 rwlock_read_unlock( & arp_globals.lock );
  504.                 return ENOENT;
  505.             }
  506.             ERROR_CODE = measured_strings_reply( translation, 1 );
  507.             rwlock_read_unlock( & arp_globals.lock );
  508.             return ERROR_CODE;
  509.         case NET_ARP_CLEAR_DEVICE:
  510.             return arp_clear_device_req( 0, IPC_GET_DEVICE( call ));
  511.         case NET_ARP_CLEAN_CACHE:
  512.             return arp_clean_cache_req( 0 );
  513.     }
  514.     return ENOTSUP;
  515. }
  516.  
  517. void arp_receiver( ipc_callid_t iid, ipc_call_t * icall ){
  518.     ERROR_DECLARE;
  519.  
  520.     packet_t        packet;
  521.  
  522.     while( true ){
  523.         switch( IPC_GET_METHOD( * icall )){
  524.             case NET_IL_DEVICE_STATE:
  525.                 // do nothing - keep the cache
  526.                 ipc_answer_0( iid, EOK );
  527.                 break;
  528.             case NET_IL_RECEIVED:
  529.                 if( ! ERROR_OCCURRED( packet_translate( arp_globals.net_phone, & packet, IPC_GET_PACKET( icall )))){
  530.                     rwlock_read_lock( & arp_globals.lock );
  531.                     ERROR_CODE = arp_receive_message( IPC_GET_DEVICE( icall ), packet );
  532.                     rwlock_read_unlock( & arp_globals.lock );
  533.                 }
  534.                 ipc_answer_0( iid, ERROR_CODE );
  535.                 break;
  536.             default:
  537.                 ipc_answer_0( iid, ENOTSUP );
  538.         }
  539.         iid = async_get_call( icall );
  540.     }
  541. }
  542.  
  543. /** @}
  544.  */
  545.