git.sur5r.net Git - freertos/blob - FreeRTOS-Plus/Source/FreeRTOS-Plus-TCP/FreeRTOS_UDP_IP.c

   1 /*
   2  * FreeRTOS+TCP V2.2.1
   3  * Copyright (C) 2017 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy of
   6  * this software and associated documentation files (the "Software"), to deal in
   7  * the Software without restriction, including without limitation the rights to
   8  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
   9  * the Software, and to permit persons to whom the Software is furnished to do so,
  10  * subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in all
  13  * copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  17  * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
  18  * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  19  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  20  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  21  *
  22  * http://aws.amazon.com/freertos
  23  * http://www.FreeRTOS.org
  24  */
  25
  26 /* Standard includes. */
  27 #include <stdint.h>
  28 #include <stdio.h>
  29
  30 /* FreeRTOS includes. */
  31 #include "FreeRTOS.h"
  32 #include "task.h"
  33 #include "queue.h"
  34 #include "semphr.h"
  35
  36 /* FreeRTOS+TCP includes. */
  37 #include "FreeRTOS_IP.h"
  38 #include "FreeRTOS_Sockets.h"
  39 #include "FreeRTOS_IP_Private.h"
  40 #include "FreeRTOS_UDP_IP.h"
  41 #include "FreeRTOS_ARP.h"
  42 #include "FreeRTOS_DHCP.h"
  43 #include "NetworkInterface.h"
  44 #include "NetworkBufferManagement.h"
  45
  46 #if( ipconfigUSE_DNS == 1 )
  47         #include "FreeRTOS_DNS.h"
  48 #endif
  49
  50 /* The expected IP version and header length coded into the IP header itself. */
  51 #define ipIP_VERSION_AND_HEADER_LENGTH_BYTE ( ( uint8_t ) 0x45 )
  52
  53 /* Part of the Ethernet and IP headers are always constant when sending an IPv4
  54 UDP packet.  This array defines the constant parts, allowing this part of the
  55 packet to be filled in using a simple memcpy() instead of individual writes. */
  56 UDPPacketHeader_t xDefaultPartUDPPacketHeader =
  57 {
  58         /* .ucBytes : */
  59         {
  60                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,     /* Ethernet source MAC address. */
  61                 0x08, 0x00,                                                     /* Ethernet frame type. */
  62                 ipIP_VERSION_AND_HEADER_LENGTH_BYTE,    /* ucVersionHeaderLength. */
  63                 0x00,                                                                   /* ucDifferentiatedServicesCode. */
  64                 0x00, 0x00,                                                     /* usLength. */
  65                 0x00, 0x00,                                                     /* usIdentification. */
  66                 0x00, 0x00,                                                     /* usFragmentOffset. */
  67                 ipconfigUDP_TIME_TO_LIVE,                               /* ucTimeToLive */
  68                 ipPROTOCOL_UDP,                                                 /* ucProtocol. */
  69                 0x00, 0x00,                                                     /* usHeaderChecksum. */
  70                 0x00, 0x00, 0x00, 0x00                                  /* Source IP address. */
  71         }
  72 };
  73 /*-----------------------------------------------------------*/
  74
  75 void vProcessGeneratedUDPPacket( NetworkBufferDescriptor_t * const pxNetworkBuffer )
  76 {
  77 UDPPacket_t *pxUDPPacket;
  78 IPHeader_t *pxIPHeader;
  79 eARPLookupResult_t eReturned;
  80 uint32_t ulIPAddress = pxNetworkBuffer->ulIPAddress;
  81 size_t uxPayloadSize;
  82
  83         /* Map the UDP packet onto the start of the frame. */
  84         pxUDPPacket = ( UDPPacket_t * ) pxNetworkBuffer->pucEthernetBuffer;
  85
  86 #if ipconfigSUPPORT_OUTGOING_PINGS == 1
  87         if( pxNetworkBuffer->usPort == ipPACKET_CONTAINS_ICMP_DATA )
  88         {
  89                 uxPayloadSize = pxNetworkBuffer->xDataLength - sizeof( ICMPPacket_t );
  90         }
  91         else
  92 #endif
  93         {
  94                 uxPayloadSize = pxNetworkBuffer->xDataLength - sizeof( UDPPacket_t );
  95         }
  96
  97         /* Determine the ARP cache status for the requested IP address. */
  98         eReturned = eARPGetCacheEntry( &( ulIPAddress ), &( pxUDPPacket->xEthernetHeader.xDestinationAddress ) );
  99
 100         if( eReturned != eCantSendPacket )
 101         {
 102                 if( eReturned == eARPCacheHit )
 103                 {
 104                         #if( ipconfigDRIVER_INCLUDED_TX_IP_CHECKSUM == 0 )
 105                                 uint8_t ucSocketOptions;
 106                         #endif
 107                         iptraceSENDING_UDP_PACKET( pxNetworkBuffer->ulIPAddress );
 108
 109                         /* Create short cuts to the data within the packet. */
 110                         pxIPHeader = &( pxUDPPacket->xIPHeader );
 111
 112                 #if ( ipconfigSUPPORT_OUTGOING_PINGS == 1 )
 113                         /* Is it possible that the packet is not actually a UDP packet
 114                         after all, but an ICMP packet. */
 115                         if( pxNetworkBuffer->usPort != ipPACKET_CONTAINS_ICMP_DATA )
 116                 #endif /* ipconfigSUPPORT_OUTGOING_PINGS */
 117                         {
 118                         UDPHeader_t *pxUDPHeader;
 119
 120                                 pxUDPHeader = &( pxUDPPacket->xUDPHeader );
 121
 122                                 pxUDPHeader->usDestinationPort = pxNetworkBuffer->usPort;
 123                                 pxUDPHeader->usSourcePort = pxNetworkBuffer->usBoundPort;
 124                                 pxUDPHeader->usLength = ( uint16_t ) ( uxPayloadSize + sizeof( UDPHeader_t ) );
 125                                 pxUDPHeader->usLength = FreeRTOS_htons( pxUDPHeader->usLength );
 126                                 pxUDPHeader->usChecksum = 0u;
 127                         }
 128
 129                         /* memcpy() the constant parts of the header information into
 130                         the     correct location within the packet.  This fills in:
 131                                 xEthernetHeader.xSourceAddress
 132                                 xEthernetHeader.usFrameType
 133                                 xIPHeader.ucVersionHeaderLength
 134                                 xIPHeader.ucDifferentiatedServicesCode
 135                                 xIPHeader.usLength
 136                                 xIPHeader.usIdentification
 137                                 xIPHeader.usFragmentOffset
 138                                 xIPHeader.ucTimeToLive
 139                                 xIPHeader.ucProtocol
 140                         and
 141                                 xIPHeader.usHeaderChecksum
 142                         */
 143                         /* Save options now, as they will be overwritten by memcpy */
 144                         #if( ipconfigDRIVER_INCLUDED_TX_IP_CHECKSUM == 0 )
 145                                 ucSocketOptions = pxNetworkBuffer->pucEthernetBuffer[ ipSOCKET_OPTIONS_OFFSET ];
 146                         #endif
 147                         /*
 148                          * Offset the memcpy by the size of a MAC address to start at the packet's
 149                          * Ethernet header 'source' MAC address; the preceding 'destination' should not be altered.
 150                          */
 151                         char *pxUdpSrcAddrOffset = ( char *) pxUDPPacket + sizeof( MACAddress_t );
 152                         memcpy( pxUdpSrcAddrOffset, xDefaultPartUDPPacketHeader.ucBytes, sizeof( xDefaultPartUDPPacketHeader ) );
 153
 154                 #if ipconfigSUPPORT_OUTGOING_PINGS == 1
 155                         if( pxNetworkBuffer->usPort == ipPACKET_CONTAINS_ICMP_DATA )
 156                         {
 157                                 pxIPHeader->ucProtocol = ipPROTOCOL_ICMP;
 158                                 pxIPHeader->usLength = ( uint16_t ) ( uxPayloadSize + sizeof( IPHeader_t ) + sizeof( ICMPHeader_t ) );
 159                         }
 160                         else
 161                 #endif /* ipconfigSUPPORT_OUTGOING_PINGS */
 162                         {
 163                                 pxIPHeader->usLength = ( uint16_t ) ( uxPayloadSize + sizeof( IPHeader_t ) + sizeof( UDPHeader_t ) );
 164                         }
 165
 166                         pxIPHeader->usLength = FreeRTOS_htons( pxIPHeader->usLength );
 167                         /* HT:endian: changed back to network endian */
 168                         pxIPHeader->ulDestinationIPAddress = pxNetworkBuffer->ulIPAddress;
 169
 170                         #if( ipconfigUSE_LLMNR == 1 )
 171                         {
 172                                 /* LLMNR messages are typically used on a LAN and they're
 173                                  * not supposed to cross routers */
 174                                 if( pxNetworkBuffer->ulIPAddress == ipLLMNR_IP_ADDR )
 175                                 {
 176                                         pxIPHeader->ucTimeToLive = 0x01;
 177                                 }
 178                         }
 179                         #endif
 180
 181                         #if( ipconfigDRIVER_INCLUDED_TX_IP_CHECKSUM == 0 )
 182                         {
 183                                 pxIPHeader->usHeaderChecksum = 0u;
 184                                 pxIPHeader->usHeaderChecksum = usGenerateChecksum( 0UL, ( uint8_t * ) &( pxIPHeader->ucVersionHeaderLength ), ipSIZE_OF_IPv4_HEADER );
 185                                 pxIPHeader->usHeaderChecksum = ~FreeRTOS_htons( pxIPHeader->usHeaderChecksum );
 186
 187                                 if( ( ucSocketOptions & ( uint8_t ) FREERTOS_SO_UDPCKSUM_OUT ) != 0u )
 188                                 {
 189                                         usGenerateProtocolChecksum( (uint8_t*)pxUDPPacket, pxNetworkBuffer->xDataLength, pdTRUE );
 190                                 }
 191                                 else
 192                                 {
 193                                         pxUDPPacket->xUDPHeader.usChecksum = 0u;
 194                                 }
 195                         }
 196                         #endif
 197                 }
 198                 else if( eReturned == eARPCacheMiss )
 199                 {
 200                         /* Add an entry to the ARP table with a null hardware address.
 201                         This allows the ARP timer to know that an ARP reply is
 202                         outstanding, and perform retransmissions if necessary. */
 203                         vARPRefreshCacheEntry( NULL, ulIPAddress );
 204
 205                         /* Generate an ARP for the required IP address. */
 206                         iptracePACKET_DROPPED_TO_GENERATE_ARP( pxNetworkBuffer->ulIPAddress );
 207                         pxNetworkBuffer->ulIPAddress = ulIPAddress;
 208                         vARPGenerateRequestPacket( pxNetworkBuffer );
 209                 }
 210                 else
 211                 {
 212                         /* The lookup indicated that an ARP request has already been
 213                         sent out for the queried IP address. */
 214                         eReturned = eCantSendPacket;
 215                 }
 216         }
 217
 218         if( eReturned != eCantSendPacket )
 219         {
 220                 /* The network driver is responsible for freeing the network buffer
 221                 after the packet has been sent. */
 222
 223                 #if defined( ipconfigETHERNET_MINIMUM_PACKET_BYTES )
 224                 {
 225                         if( pxNetworkBuffer->xDataLength < ( size_t ) ipconfigETHERNET_MINIMUM_PACKET_BYTES )
 226                         {
 227                         BaseType_t xIndex;
 228
 229                                 for( xIndex = ( BaseType_t ) pxNetworkBuffer->xDataLength; xIndex < ( BaseType_t ) ipconfigETHERNET_MINIMUM_PACKET_BYTES; xIndex++ )
 230                                 {
 231                                         pxNetworkBuffer->pucEthernetBuffer[ xIndex ] = 0u;
 232                                 }
 233                                 pxNetworkBuffer->xDataLength = ( size_t ) ipconfigETHERNET_MINIMUM_PACKET_BYTES;
 234                         }
 235                 }
 236                 #endif
 237
 238                 xNetworkInterfaceOutput( pxNetworkBuffer, pdTRUE );
 239         }
 240         else
 241         {
 242                 /* The packet can't be sent (DHCP not completed?).  Just drop the
 243                 packet. */
 244                 vReleaseNetworkBufferAndDescriptor( pxNetworkBuffer );
 245         }
 246 }
 247 /*-----------------------------------------------------------*/
 248
 249 BaseType_t xProcessReceivedUDPPacket( NetworkBufferDescriptor_t *pxNetworkBuffer, uint16_t usPort )
 250 {
 251 BaseType_t xReturn = pdPASS;
 252 FreeRTOS_Socket_t *pxSocket;
 253 configASSERT(pxNetworkBuffer);
 254 configASSERT(pxNetworkBuffer->pucEthernetBuffer);
 255
 256
 257 UDPPacket_t *pxUDPPacket = (UDPPacket_t *) pxNetworkBuffer->pucEthernetBuffer;
 258
 259         /* Caller must check for minimum packet size. */
 260         pxSocket = pxUDPSocketLookup( usPort );
 261
 262         if( pxSocket )
 263         {
 264
 265                 /* When refreshing the ARP cache with received UDP packets we must be
 266                 careful;  hundreds of broadcast messages may pass and if we're not
 267                 handling them, no use to fill the ARP cache with those IP addresses. */
 268                 vARPRefreshCacheEntry( &( pxUDPPacket->xEthernetHeader.xSourceAddress ), pxUDPPacket->xIPHeader.ulSourceIPAddress );
 269
 270                 #if( ipconfigUSE_CALLBACKS == 1 )
 271                 {
 272                         /* Did the owner of this socket register a reception handler ? */
 273                         if( ipconfigIS_VALID_PROG_ADDRESS( pxSocket->u.xUDP.pxHandleReceive ) )
 274                         {
 275                                 struct freertos_sockaddr xSourceAddress, destinationAddress;
 276                                 void *pcData = ( void * ) &( pxNetworkBuffer->pucEthernetBuffer[ ipUDP_PAYLOAD_OFFSET_IPv4 ] );
 277                                 FOnUDPReceive_t xHandler = ( FOnUDPReceive_t ) pxSocket->u.xUDP.pxHandleReceive;
 278                                 xSourceAddress.sin_port = pxNetworkBuffer->usPort;
 279                                 xSourceAddress.sin_addr = pxNetworkBuffer->ulIPAddress;
 280                                 destinationAddress.sin_port = usPort;
 281                                 destinationAddress.sin_addr = pxUDPPacket->xIPHeader.ulDestinationIPAddress;
 282
 283                                 /* The value of 'xDataLength' was proven to be at least the size of a UDP packet in prvProcessIPPacket(). */
 284                                 if( xHandler( ( Socket_t ) pxSocket, ( void* ) pcData, ( size_t ) ( pxNetworkBuffer->xDataLength - ipUDP_PAYLOAD_OFFSET_IPv4 ),
 285                                         &xSourceAddress, &destinationAddress ) )
 286                                 {
 287                                         xReturn = pdFAIL; /* FAIL means that we did not consume or release the buffer */
 288                                 }
 289                         }
 290                 }
 291                 #endif /* ipconfigUSE_CALLBACKS */
 292
 293                 #if( ipconfigUDP_MAX_RX_PACKETS > 0 )
 294                 {
 295                         if( xReturn == pdPASS )
 296                         {
 297                                 if ( listCURRENT_LIST_LENGTH( &( pxSocket->u.xUDP.xWaitingPacketsList ) ) >= pxSocket->u.xUDP.uxMaxPackets )
 298                                 {
 299                                         FreeRTOS_debug_printf( ( "xProcessReceivedUDPPacket: buffer full %ld >= %ld port %u\n",
 300                                                 listCURRENT_LIST_LENGTH( &( pxSocket->u.xUDP.xWaitingPacketsList ) ),
 301                                                 pxSocket->u.xUDP.uxMaxPackets, pxSocket->usLocalPort ) );
 302                                         xReturn = pdFAIL; /* we did not consume or release the buffer */
 303                                 }
 304                         }
 305                 }
 306                 #endif
 307
 308                 if( xReturn == pdPASS )
 309                 {
 310                         vTaskSuspendAll();
 311                         {
 312                                 if( xReturn == pdPASS )
 313                                 {
 314                                         taskENTER_CRITICAL();
 315                                         {
 316                                                 /* Add the network packet to the list of packets to be
 317                                                 processed by the socket. */
 318                                                 vListInsertEnd( &( pxSocket->u.xUDP.xWaitingPacketsList ), &( pxNetworkBuffer->xBufferListItem ) );
 319                                         }
 320                                         taskEXIT_CRITICAL();
 321                                 }
 322                         }
 323                         xTaskResumeAll();
 324
 325                         /* Set the socket's receive event */
 326                         if( pxSocket->xEventGroup != NULL )
 327                         {
 328                                 xEventGroupSetBits( pxSocket->xEventGroup, eSOCKET_RECEIVE );
 329                         }
 330
 331                         #if( ipconfigSUPPORT_SELECT_FUNCTION == 1 )
 332                         {
 333                                 if( ( pxSocket->pxSocketSet != NULL ) && ( ( pxSocket->xSelectBits & eSELECT_READ ) != 0 ) )
 334                                 {
 335                                         xEventGroupSetBits( pxSocket->pxSocketSet->xSelectGroup, eSELECT_READ );
 336                                 }
 337                         }
 338                         #endif
 339
 340                         #if( ipconfigSOCKET_HAS_USER_SEMAPHORE == 1 )
 341                         {
 342                                 if( pxSocket->pxUserSemaphore != NULL )
 343                                 {
 344                                         xSemaphoreGive( pxSocket->pxUserSemaphore );
 345                                 }
 346                         }
 347                         #endif
 348
 349                         #if( ipconfigUSE_DHCP == 1 )
 350                         {
 351                                 if( xIsDHCPSocket( pxSocket ) )
 352                                 {
 353                                         xSendEventToIPTask( eDHCPEvent );
 354                                 }
 355                         }
 356                         #endif
 357                 }
 358         }
 359         else
 360         {
 361                 /* There is no socket listening to the target port, but still it might
 362                 be for this node. */
 363
 364                 #if( ipconfigUSE_DNS == 1 ) && ( ipconfigDNS_USE_CALLBACKS == 1 )
 365                         /* A DNS reply, check for the source port.  Although the DNS client
 366                         does open a UDP socket to send a messages, this socket will be
 367                         closed after a short timeout.  Messages that come late (after the
 368                         socket is closed) will be treated here. */
 369                         if( FreeRTOS_ntohs( pxUDPPacket->xUDPHeader.usSourcePort ) == ipDNS_PORT )
 370                         {
 371                                 vARPRefreshCacheEntry( &( pxUDPPacket->xEthernetHeader.xSourceAddress ), pxUDPPacket->xIPHeader.ulSourceIPAddress );
 372                                 xReturn = ( BaseType_t )ulDNSHandlePacket( pxNetworkBuffer );
 373                         }
 374                         else
 375                 #endif
 376
 377                 #if( ipconfigUSE_LLMNR == 1 )
 378                         /* a LLMNR request, check for the destination port. */
 379                         if( ( usPort == FreeRTOS_ntohs( ipLLMNR_PORT ) ) ||
 380                                 ( pxUDPPacket->xUDPHeader.usSourcePort == FreeRTOS_ntohs( ipLLMNR_PORT ) ) )
 381                         {
 382                                 vARPRefreshCacheEntry( &( pxUDPPacket->xEthernetHeader.xSourceAddress ), pxUDPPacket->xIPHeader.ulSourceIPAddress );
 383                                 xReturn = ( BaseType_t )ulDNSHandlePacket( pxNetworkBuffer );
 384                         }
 385                         else
 386                 #endif /* ipconfigUSE_LLMNR */
 387
 388                 #if( ipconfigUSE_NBNS == 1 )
 389                         /* a NetBIOS request, check for the destination port */
 390                         if( ( usPort == FreeRTOS_ntohs( ipNBNS_PORT ) ) ||
 391                                 ( pxUDPPacket->xUDPHeader.usSourcePort == FreeRTOS_ntohs( ipNBNS_PORT ) ) )
 392                         {
 393                                 vARPRefreshCacheEntry( &( pxUDPPacket->xEthernetHeader.xSourceAddress ), pxUDPPacket->xIPHeader.ulSourceIPAddress );
 394                                 xReturn = ( BaseType_t )ulNBNSHandlePacket( pxNetworkBuffer );
 395                         }
 396                         else
 397                 #endif /* ipconfigUSE_NBNS */
 398                 {
 399                         xReturn = pdFAIL;
 400                 }
 401         }
 402
 403         return xReturn;
 404 }
 405 /*-----------------------------------------------------------*/