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IPv4/single: Update ARP cache from gratuitous ARP packets v2 #482

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IPv4/single: Update ARP cache from gratuitous ARP packets v2 #482

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a194165
Let the TCP timer becomes expired in stead of active
Jun 10, 2022
da209a1
Merge branch 'main' into repair_tcp_timer
htibosch Jun 10, 2022
23b7268
Renamed parameter of function vIPSetTCPTimerExpiredState
Jun 10, 2022
407d22d
Adapt unit tests to use the new name and field
Jun 10, 2022
8bab49e
Change bActive to bExpired
Jun 10, 2022
5497db5
Empty commit
AniruddhaKanhere Jun 10, 2022
b1b0d2b
Fix spell check
AniruddhaKanhere Jun 10, 2022
f1d0b19
When a gratuitous ARP is received, use it to update the ARP cache entry
Jun 13, 2022
d1bf030
Merge branch 'main' into ipv4_single_update_arp_from_gratuitous_arp_v2
htibosch Oct 27, 2022
b298eb6
Merge branch 'main' into ipv4_single_update_arp_from_gratuitous_arp_v2
AniruddhaKanhere Nov 17, 2022
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87 changes: 51 additions & 36 deletions source/FreeRTOS_ARP.c
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Original file line number Diff line number Diff line change
Expand Up @@ -250,43 +250,58 @@ eFrameProcessingResult_t eARPProcessPacket( ARPPacket_t * const pxARPFrame )
case ipARP_REQUEST:

/* The packet contained an ARP request. Was it for the IP
* address of the node running this code? And does the MAC
* address claim that it is coming from this device itself? */
if( ( ulTargetProtocolAddress == *ipLOCAL_IP_ADDRESS_POINTER ) &&
( memcmp( ( void * ) ipLOCAL_MAC_ADDRESS,
( void * ) ( pxARPHeader->xSenderHardwareAddress.ucBytes ),
ipMAC_ADDRESS_LENGTH_BYTES ) != 0 ) )
* address of the node running this code? */
if( ulTargetProtocolAddress == *ipLOCAL_IP_ADDRESS_POINTER )
{
iptraceSENDING_ARP_REPLY( ulSenderProtocolAddress );

/* The request is for the address of this node. Add the
* entry into the ARP cache, or refresh the entry if it
* already exists. */
vARPRefreshCacheEntry( &( pxARPHeader->xSenderHardwareAddress ), ulSenderProtocolAddress );

/* Generate a reply payload in the same buffer. */
pxARPHeader->usOperation = ( uint16_t ) ipARP_REPLY;

( void ) memcpy( &( pxARPHeader->xTargetHardwareAddress ),
&( pxARPHeader->xSenderHardwareAddress ),
sizeof( MACAddress_t ) );

pxARPHeader->ulTargetProtocolAddress = ulSenderProtocolAddress;

/*
* Use helper variables for memcpy() to remain
* compliant with MISRA Rule 21.15. These should be
* optimized away.
*/
pvCopySource = ipLOCAL_MAC_ADDRESS;
pvCopyDest = pxARPHeader->xSenderHardwareAddress.ucBytes;
( void ) memcpy( pvCopyDest, pvCopySource, sizeof( MACAddress_t ) );

pvCopySource = ipLOCAL_IP_ADDRESS_POINTER;
pvCopyDest = pxARPHeader->ucSenderProtocolAddress;
( void ) memcpy( pvCopyDest, pvCopySource, sizeof( pxARPHeader->ucSenderProtocolAddress ) );

eReturn = eReturnEthernetFrame;
/* Does the MAC address claim that it is coming
* from this device itself? */
if( memcmp( ( void * ) ipLOCAL_MAC_ADDRESS,
( void * ) ( pxARPHeader->xSenderHardwareAddress.ucBytes ),
ipMAC_ADDRESS_LENGTH_BYTES ) != 0 )
{
iptraceSENDING_ARP_REPLY( ulSenderProtocolAddress );

/* The request is for the address of this node. Add the
* entry into the ARP cache, or refresh the entry if it
* already exists. */
vARPRefreshCacheEntry( &( pxARPHeader->xSenderHardwareAddress ), ulSenderProtocolAddress );

/* Generate a reply payload in the same buffer. */
pxARPHeader->usOperation = ( uint16_t ) ipARP_REPLY;

( void ) memcpy( &( pxARPHeader->xTargetHardwareAddress ),
&( pxARPHeader->xSenderHardwareAddress ),
sizeof( MACAddress_t ) );

pxARPHeader->ulTargetProtocolAddress = ulSenderProtocolAddress;

/*
* Use helper variables for memcpy() to remain
* compliant with MISRA Rule 21.15. These should be
* optimized away.
*/
pvCopySource = ipLOCAL_MAC_ADDRESS;
pvCopyDest = pxARPHeader->xSenderHardwareAddress.ucBytes;
( void ) memcpy( pvCopyDest, pvCopySource, sizeof( MACAddress_t ) );

pvCopySource = ipLOCAL_IP_ADDRESS_POINTER;
pvCopyDest = pxARPHeader->ucSenderProtocolAddress;
( void ) memcpy( pvCopyDest, pvCopySource, sizeof( pxARPHeader->ucSenderProtocolAddress ) );

eReturn = eReturnEthernetFrame;
}
}
else if( ulSenderProtocolAddress == ulTargetProtocolAddress ) /* Gratuitous ARP request? */
{
MACAddress_t xHardwareAddress;

/* The request is a Gratuitous ARP message.
* Refresh the entry if it already exists. */
/* Determine the ARP cache status for the requested IP address. */
if( eARPGetCacheEntry( &( ulSenderProtocolAddress ), &( xHardwareAddress ) ) == eARPCacheHit )
{
vARPRefreshCacheEntry( &( pxARPHeader->xSenderHardwareAddress ), ulSenderProtocolAddress );
}
}

break;
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