/*
* FreeRTOS+TCP V3.1.0
* Copyright (C) 2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* SPDX-License-Identifier: MIT
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* http://aws.amazon.com/freertos
* http://www.FreeRTOS.org
*/
/**
* @file FreeRTOS_IP_Utils.c
* @brief Implements the basic functionality for the FreeRTOS+TCP network stack.
*/
/* Standard includes. */
#include <stdint.h>
#include <stdio.h>
#include <string.h>
/* FreeRTOS includes. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"
#include "semphr.h"
/* FreeRTOS+TCP includes. */
#include "FreeRTOS_IP.h"
#include "FreeRTOS_IP_Utils.h"
#include "FreeRTOS_IP_Timers.h"
#include "FreeRTOS_Sockets.h"
#include "FreeRTOS_IP_Private.h"
#include "FreeRTOS_ARP.h"
#include "FreeRTOS_UDP_IP.h"
#include "FreeRTOS_DHCP.h"
#include "NetworkInterface.h"
#include "NetworkBufferManagement.h"
#include "FreeRTOS_DNS.h"
/* Used to ensure the structure packing is having the desired effect. The
* 'volatile' is used to prevent compiler warnings about comparing a constant with
* a constant. */
#ifndef _lint
#define ipEXPECTED_EthernetHeader_t_SIZE ( ( size_t ) 14 ) /**< Ethernet Header size in bytes. */
#define ipEXPECTED_ARPHeader_t_SIZE ( ( size_t ) 28 ) /**< ARP header size in bytes. */
#define ipEXPECTED_IPHeader_t_SIZE ( ( size_t ) 20 ) /**< IP header size in bytes. */
#define ipEXPECTED_IGMPHeader_t_SIZE ( ( size_t ) 8 ) /**< IGMP header size in bytes. */
#define ipEXPECTED_ICMPHeader_t_SIZE ( ( size_t ) 8 ) /**< ICMP header size in bytes. */
#define ipEXPECTED_UDPHeader_t_SIZE ( ( size_t ) 8 ) /**< UDP header size in bytes. */
#define ipEXPECTED_TCPHeader_t_SIZE ( ( size_t ) 20 ) /**< TCP header size in bytes. */
#endif
/** @brief Time delay between repeated attempts to initialise the network hardware. */
#ifndef ipINITIALISATION_RETRY_DELAY
#define ipINITIALISATION_RETRY_DELAY ( pdMS_TO_TICKS( 3000U ) )
#endif
#if ( ipconfigUSE_NETWORK_EVENT_HOOK == 1 )
/* used for unit testing */
/* MISRA Ref 8.9.1 [File scoped variables] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-89 */
/* coverity[misra_c_2012_rule_8_9_violation] */
/* coverity[single_use] */
static BaseType_t xCallEventHook = pdFALSE;
#endif
#if ( ipconfigHAS_PRINTF != 0 )
/** @brief Last value of minimum buffer count. */
static UBaseType_t uxLastMinBufferCount = ipconfigNUM_NETWORK_BUFFER_DESCRIPTORS;
/** @brief Last value of minimum size. Used in printing resource stats. */
static size_t uxMinLastSize = 0u;
#endif
#if ( ipconfigCHECK_IP_QUEUE_SPACE != 0 ) && ( ipconfigHAS_PRINTF != 0 )
static UBaseType_t uxLastMinQueueSpace = 0;
#endif
/**
* Used in checksum calculation.
*/
typedef union _xUnion32
{
uint32_t u32; /**< The 32-bit member of the union. */
uint16_t u16[ 2 ]; /**< The array of 2 16-bit members of the union. */
uint8_t u8[ 4 ]; /**< The array of 4 8-bit members of the union. */
} xUnion32;
/**
* Used in checksum calculation.
*/
typedef union _xUnionPtr
{
const uint32_t * u32ptr; /**< The pointer member to a 32-bit variable. */
const uint16_t * u16ptr; /**< The pointer member to a 16-bit variable. */
const uint8_t * u8ptr; /**< The pointer member to an 8-bit variable. */
} xUnionPtr;
/*
* Returns the network buffer descriptor that owns a given packet buffer.
*/
static NetworkBufferDescriptor_t * prvPacketBuffer_to_NetworkBuffer( const void * pvBuffer,
size_t uxOffset );
#if ( ipconfigUSE_DHCP != 0 )
/**
* @brief Create a DHCP event.
*
* @return pdPASS or pdFAIL, depending on whether xSendEventStructToIPTask()
* succeeded.
*/
BaseType_t xSendDHCPEvent( void )
{
IPStackEvent_t xEventMessage;
const TickType_t uxDontBlock = 0U;
uintptr_t uxOption = ( uintptr_t ) eGetDHCPState();
xEventMessage.eEventType = eDHCPEvent;
/* MISRA Ref 11.6.1 [DHCP events and conversion to void] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-116 */
/* coverity[misra_c_2012_rule_11_6_violation] */
xEventMessage.pvData = ( void * ) uxOption;
return xSendEventStructToIPTask( &xEventMessage, uxDontBlock );
}
/*-----------------------------------------------------------*/
#endif /* ( ipconfigUSE_DHCP != 0 ) */
/**
* @brief Set multicast MAC address.
*
* @param[in] ulIPAddress: IP address.
* @param[out] pxMACAddress: Pointer to MAC address.
*/
void vSetMultiCastIPv4MacAddress( uint32_t ulIPAddress,
MACAddress_t * pxMACAddress )
{
uint32_t ulIP = FreeRTOS_ntohl( ulIPAddress );
pxMACAddress->ucBytes[ 0 ] = ( uint8_t ) 0x01U;
pxMACAddress->ucBytes[ 1 ] = ( uint8_t ) 0x00U;
pxMACAddress->ucBytes[ 2 ] = ( uint8_t ) 0x5EU;
pxMACAddress->ucBytes[ 3 ] = ( uint8_t ) ( ( ulIP >> 16 ) & 0x7fU ); /* Use 7 bits. */
pxMACAddress->ucBytes[ 4 ] = ( uint8_t ) ( ( ulIP >> 8 ) & 0xffU ); /* Use 8 bits. */
pxMACAddress->ucBytes[ 5 ] = ( uint8_t ) ( ( ulIP ) & 0xffU ); /* Use 8 bits. */
}
/*-----------------------------------------------------------*/
/**
* @brief Duplicate the given network buffer descriptor with a modified length.
*
* @param[in] pxNetworkBuffer: The network buffer to be duplicated.
* @param[in] uxNewLength: The length for the new buffer.
*
* @return If properly duplicated, then the duplicate network buffer or else, NULL.
*/
NetworkBufferDescriptor_t * pxDuplicateNetworkBufferWithDescriptor( const NetworkBufferDescriptor_t * const pxNetworkBuffer,
size_t uxNewLength )
{
NetworkBufferDescriptor_t * pxNewBuffer;
size_t uxLengthToCopy = uxNewLength;
/* This function is only used when 'ipconfigZERO_COPY_TX_DRIVER' is set to 1.
* The transmit routine wants to have ownership of the network buffer
* descriptor, because it will pass the buffer straight to DMA. */
pxNewBuffer = pxGetNetworkBufferWithDescriptor( uxNewLength, ( TickType_t ) 0 );
if( pxNewBuffer != NULL )
{
/* Get the minimum of both values to copy the data. */
if( uxLengthToCopy > pxNetworkBuffer->xDataLength )
{
uxLengthToCopy = pxNetworkBuffer->xDataLength;
}
/* Set the actual packet size in case a bigger buffer than requested
* was returned. */
pxNewBuffer->xDataLength = uxNewLength;
/* Copy the original packet information. */
pxNewBuffer->ulIPAddress = pxNetworkBuffer->ulIPAddress;
pxNewBuffer->usPort = pxNetworkBuffer->usPort;
pxNewBuffer->usBoundPort = pxNetworkBuffer->usBoundPort;
( void ) memcpy( pxNewBuffer->pucEthernetBuffer, pxNetworkBuffer->pucEthernetBuffer, uxLengthToCopy );
}
return pxNewBuffer;
}
/*-----------------------------------------------------------*/
/**
* @brief Get the network buffer descriptor from the packet buffer.
*
* @param[in] pvBuffer: The pointer to packet buffer.
* @param[in] uxOffset: Additional offset (such as the packet length of UDP packet etc.).
*
* @return The network buffer descriptor if the alignment is correct. Else a NULL is returned.
*/
static NetworkBufferDescriptor_t * prvPacketBuffer_to_NetworkBuffer( const void * pvBuffer,
size_t uxOffset )
{
uintptr_t uxBuffer;
NetworkBufferDescriptor_t * pxResult;
if( pvBuffer == NULL )
{
pxResult = NULL;
}
else
{
/* Obtain the network buffer from the zero copy pointer. */
/* MISRA Ref 11.6.2 [Pointer arithmetic and hidden pointer] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-116 */
/* coverity[misra_c_2012_rule_11_6_violation] */
uxBuffer = ( uintptr_t ) pvBuffer;
/* The input here is a pointer to a packet buffer plus some offset. Subtract
* this offset, and also the size of the header in the network buffer, usually
* 8 + 2 bytes. */
uxBuffer -= ( uxOffset + ipBUFFER_PADDING );
/* Here a pointer was placed to the network descriptor. As a
* pointer is dereferenced, make sure it is well aligned. */
if( ( uxBuffer & ( ( ( uintptr_t ) sizeof( uxBuffer ) ) - 1U ) ) == ( uintptr_t ) 0U )
{
/* MISRA Ref 11.4.2 [Validation of pointer alignment] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-114 */
/* coverity[misra_c_2012_rule_11_4_violation] */
pxResult = *( ( NetworkBufferDescriptor_t ** ) uxBuffer );
}
else
{
pxResult = NULL;
}
}
return pxResult;
}
/*-----------------------------------------------------------*/
#if ( ipconfigZERO_COPY_TX_DRIVER != 0 ) || ( ipconfigZERO_COPY_RX_DRIVER != 0 )
/**
* @brief Get the network buffer from the packet buffer.
*
* @param[in] pvBuffer: Pointer to the packet buffer.
*
* @return The network buffer if the alignment is correct. Else a NULL is returned.
*/
NetworkBufferDescriptor_t * pxPacketBuffer_to_NetworkBuffer( const void * pvBuffer )
{
return prvPacketBuffer_to_NetworkBuffer( pvBuffer, 0U );
}
#endif /* ( ipconfigZERO_COPY_TX_DRIVER != 0 ) || ( ipconfigZERO_COPY_RX_DRIVER != 0 ) */
/*-----------------------------------------------------------*/
/**
* @brief Get the network buffer from the UDP Payload buffer.
*
* @param[in] pvBuffer: Pointer to the UDP payload buffer.
*
* @return The network buffer if the alignment is correct. Else a NULL is returned.
*/
NetworkBufferDescriptor_t * pxUDPPayloadBuffer_to_NetworkBuffer( const void * pvBuffer )
{
return prvPacketBuffer_to_NetworkBuffer( pvBuffer, sizeof( UDPPacket_t ) );
}
/*-----------------------------------------------------------*/
/**
* @brief Function to check whether the current context belongs to
* the IP-task.
*
* @return If the current context belongs to the IP-task, then pdTRUE is
* returned. Else pdFALSE is returned.
*
* @note Very important: the IP-task is not allowed to call its own API's,
* because it would easily get into a dead-lock.
*/
BaseType_t xIsCallingFromIPTask( void )
{
BaseType_t xReturn;
const struct tskTaskControlBlock * const xCurrentHandle = xTaskGetCurrentTaskHandle();
const struct tskTaskControlBlock * const xCurrentIPTaskHandle = FreeRTOS_GetIPTaskHandle();
if( xCurrentHandle == xCurrentIPTaskHandle )
{
xReturn = pdTRUE;
}
else
{
xReturn = pdFALSE;
}
return xReturn;
}
/*-----------------------------------------------------------*/
/**
* @brief Process a 'Network down' event and complete required processing.
*/
/* MISRA Ref 8.9.1 [File scoped variables] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-89 */
/* coverity[misra_c_2012_rule_8_9_violation] */
/* coverity[single_use] */
void prvProcessNetworkDownEvent( void )
{
/* Stop the ARP timer while there is no network. */
vIPSetARPTimerEnableState( pdFALSE );
#if ( ipconfigUSE_NETWORK_EVENT_HOOK == 1 )
{
/* The first network down event is generated by the IP stack itself to
* initialise the network hardware, so do not call the network down event
* the first time through. */
if( xCallEventHook == pdTRUE )
{
vApplicationIPNetworkEventHook( eNetworkDown );
}
xCallEventHook = pdTRUE;
}
#endif /* if ipconfigUSE_NETWORK_EVENT_HOOK == 1 */
/* Per the ARP Cache Validation section of https://tools.ietf.org/html/rfc1122,
* treat network down as a "delivery problem" and flush the ARP cache for this
* interface. */
FreeRTOS_ClearARP();
/* The network has been disconnected (or is being initialised for the first
* time). Perform whatever hardware processing is necessary to bring it up
* again, or wait for it to be available again. This is hardware dependent. */
if( xNetworkInterfaceInitialise() != pdPASS )
{
/* Ideally the network interface initialisation function will only
* return when the network is available. In case this is not the case,
* wait a while before retrying the initialisation. */
vTaskDelay( ipINITIALISATION_RETRY_DELAY );
FreeRTOS_NetworkDown();
}
else
{
/* Set remaining time to 0 so it will become active immediately. */
#if ipconfigUSE_DHCP == 1
{
/* The network is not up until DHCP has completed. */
vDHCPProcess( pdTRUE, eInitialWait );
}
#else
{
/* Perform any necessary 'network up' processing. */
vIPNetworkUpCalls();
}
#endif
}
}
/*-----------------------------------------------------------*/
/**
* @brief Check the values of configuration options and assert on it. Also verify that the IP-task
* has not already been initialized.
*/
void vPreCheckConfigs( void )
{
/* This function should only be called once. */
configASSERT( xIPIsNetworkTaskReady() == pdFALSE );
configASSERT( xNetworkEventQueue == NULL );
configASSERT( FreeRTOS_GetIPTaskHandle() == NULL );
#if ( configASSERT_DEFINED == 1 )
{
volatile size_t uxSize = sizeof( uintptr_t );
if( uxSize == 8U )
{
/* This is a 64-bit platform, make sure there is enough space in
* pucEthernetBuffer to store a pointer. */
configASSERT( ipconfigBUFFER_PADDING >= 14 );
/* But it must have this strange alignment: */
configASSERT( ( ( ( ipconfigBUFFER_PADDING ) + 2 ) % 4 ) == 0 );
}
/* LCOV_EXCL_BR_START */
uxSize = ipconfigNETWORK_MTU;
/* Check if MTU is big enough. */
configASSERT( uxSize >= ( ipSIZE_OF_IPv4_HEADER + ipSIZE_OF_TCP_HEADER + ipconfigTCP_MSS ) );
uxSize = sizeof( EthernetHeader_t );
/* Check structure packing is correct. */
configASSERT( uxSize == ipEXPECTED_EthernetHeader_t_SIZE );
uxSize = sizeof( ARPHeader_t );
configASSERT( uxSize == ipEXPECTED_ARPHeader_t_SIZE );
uxSize = sizeof( IPHeader_t );
configASSERT( uxSize == ipEXPECTED_IPHeader_t_SIZE );
uxSize = sizeof( ICMPHeader_t );
configASSERT( uxSize == ipEXPECTED_ICMPHeader_t_SIZE );
uxSize = sizeof( UDPHeader_t );
configASSERT( uxSize == ipEXPECTED_UDPHeader_t_SIZE );
/* LCOV_EXCL_BR_STOP */
}
#endif /* if ( configASSERT_DEFINED == 1 ) */
}
/**
* @brief Generate or check the protocol checksum of the data sent in the first parameter.
* At the same time, the length of the packet and the length of the different layers
* will be checked.
*
* @param[in] pucEthernetBuffer: The Ethernet buffer for which the checksum is to be calculated
* or checked.
* @param[in] uxBufferLength: the total number of bytes received, or the number of bytes written
* in the packet buffer.
* @param[in] xOutgoingPacket: Whether this is an outgoing packet or not.
*
* @return When xOutgoingPacket is false: the error code can be either: ipINVALID_LENGTH,
* ipUNHANDLED_PROTOCOL, ipWRONG_CRC, or ipCORRECT_CRC.
* When xOutgoingPacket is true: either ipINVALID_LENGTH, ipUNHANDLED_PROTOCOL,
* or ipCORRECT_CRC.
*/
uint16_t usGenerateProtocolChecksum( uint8_t * pucEthernetBuffer,
size_t uxBufferLength,
BaseType_t xOutgoingPacket )
{
uint32_t ulLength;
uint16_t usChecksum; /* The checksum as calculated. */
uint16_t usChecksumFound = 0U; /* The checksum as found in the incoming packet. */
const IPPacket_t * pxIPPacket;
UBaseType_t uxIPHeaderLength;
ProtocolPacket_t * pxProtPack;
uint8_t ucProtocol;
#if ( ipconfigHAS_DEBUG_PRINTF != 0 )
const char * pcType;
#endif
uint16_t usLength;
uint16_t ucVersionHeaderLength;
DEBUG_DECLARE_TRACE_VARIABLE( BaseType_t, xLocation, 0 );
/* Introduce a do-while loop to allow use of break statements.
* Note: MISRA prohibits use of 'goto', thus replaced with breaks. */
do
{
/* Check for minimum packet size. */
if( uxBufferLength < sizeof( IPPacket_t ) )
{
usChecksum = ipINVALID_LENGTH;
DEBUG_SET_TRACE_VARIABLE( xLocation, 1 );
break;
}
/* Parse the packet length. */
/* MISRA Ref 11.3.1 [Misaligned access] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-113 */
/* coverity[misra_c_2012_rule_11_3_violation] */
pxIPPacket = ( ( const IPPacket_t * ) pucEthernetBuffer );
/* Per https://tools.ietf.org/html/rfc791, the four-bit Internet Header
* Length field contains the length of the internet header in 32-bit words. */
ucVersionHeaderLength = pxIPPacket->xIPHeader.ucVersionHeaderLength;
ucVersionHeaderLength = ( ucVersionHeaderLength & ( uint8_t ) 0x0FU ) << 2;
uxIPHeaderLength = ( UBaseType_t ) ucVersionHeaderLength;
/* Check for minimum packet size. */
if( uxBufferLength < ( sizeof( IPPacket_t ) + ( uxIPHeaderLength - ipSIZE_OF_IPv4_HEADER ) ) )
{
usChecksum = ipINVALID_LENGTH;
DEBUG_SET_TRACE_VARIABLE( xLocation, 2 );
break;
}
usLength = pxIPPacket->xIPHeader.usLength;
usLength = FreeRTOS_ntohs( usLength );
if( usLength < uxIPHeaderLength )
{
usChecksum = ipINVALID_LENGTH;
DEBUG_SET_TRACE_VARIABLE( xLocation, 3 );
break;
}
if( uxBufferLength < ( size_t ) ( ipSIZE_OF_ETH_HEADER + ( size_t ) usLength ) )
{
usChecksum = ipINVALID_LENGTH;
DEBUG_SET_TRACE_VARIABLE( xLocation, 4 );
break;
}
/* Identify the next protocol. */
ucProtocol = pxIPPacket->xIPHeader.ucProtocol;
/* N.B., if this IP packet header includes Options, then the following
* assignment results in a pointer into the protocol packet with the Ethernet
* and IP headers incorrectly aligned. However, either way, the "third"
* protocol (Layer 3 or 4) header will be aligned, which is the convenience
* of this calculation. */
/* MISRA Ref 11.3.1 [Misaligned access] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-113 */
/* coverity[misra_c_2012_rule_11_3_violation] */
pxProtPack = ( ( ProtocolPacket_t * ) &( pucEthernetBuffer[ uxIPHeaderLength - ipSIZE_OF_IPv4_HEADER ] ) );
/* Switch on the Layer 3/4 protocol. */
if( ucProtocol == ( uint8_t ) ipPROTOCOL_UDP )
{
if( uxBufferLength < ( uxIPHeaderLength + ipSIZE_OF_ETH_HEADER + ipSIZE_OF_UDP_HEADER ) )
{
usChecksum = ipINVALID_LENGTH;
DEBUG_SET_TRACE_VARIABLE( xLocation, 5 );
break;
}
if( xOutgoingPacket != pdFALSE )
{
/* Clear the UDP checksum field before calculating it. */
pxProtPack->xUDPPacket.xUDPHeader.usChecksum = 0U;
}
else
{
usChecksumFound = pxProtPack->xUDPPacket.xUDPHeader.usChecksum;
}
#if ( ipconfigHAS_DEBUG_PRINTF != 0 )
{
pcType = "UDP";
}
#endif /* ipconfigHAS_DEBUG_PRINTF != 0 */
}
else if( ucProtocol == ( uint8_t ) ipPROTOCOL_TCP )
{
if( uxBufferLength < ( uxIPHeaderLength + ipSIZE_OF_ETH_HEADER + ipSIZE_OF_TCP_HEADER ) )
{
usChecksum = ipINVALID_LENGTH;
DEBUG_SET_TRACE_VARIABLE( xLocation, 6 );
break;
}
if( xOutgoingPacket != pdFALSE )
{
/* Clear the TCP checksum field before calculating it. */
pxProtPack->xTCPPacket.xTCPHeader.usChecksum = 0U;
}
else
{
usChecksumFound = pxProtPack->xTCPPacket.xTCPHeader.usChecksum;
}
#if ( ipconfigHAS_DEBUG_PRINTF != 0 )
{
pcType = "TCP";
}
#endif /* ipconfigHAS_DEBUG_PRINTF != 0 */
}
else if( ( ucProtocol == ( uint8_t ) ipPROTOCOL_ICMP ) ||
( ucProtocol == ( uint8_t ) ipPROTOCOL_IGMP ) )
{
if( uxBufferLength < ( uxIPHeaderLength + ipSIZE_OF_ETH_HEADER + ipSIZE_OF_ICMP_HEADER ) )
{
usChecksum = ipINVALID_LENGTH;
DEBUG_SET_TRACE_VARIABLE( xLocation, 7 );
break;
}
if( xOutgoingPacket != pdFALSE )
{
/* Clear the ICMP/IGMP checksum field before calculating it. */
pxProtPack->xICMPPacket.xICMPHeader.usChecksum = 0U;
}
else
{
usChecksumFound = pxProtPack->xICMPPacket.xICMPHeader.usChecksum;
}
#if ( ipconfigHAS_DEBUG_PRINTF != 0 )
{
if( ucProtocol == ( uint8_t ) ipPROTOCOL_ICMP )
{
pcType = "ICMP";
}
else
{
pcType = "IGMP";
}
}
#endif /* ipconfigHAS_DEBUG_PRINTF != 0 */
}
else
{
/* Unhandled protocol, other than ICMP, IGMP, UDP, or TCP. */
usChecksum = ipUNHANDLED_PROTOCOL;
DEBUG_SET_TRACE_VARIABLE( xLocation, 8 );
break;
}
/* The protocol and checksum field have been identified. Check the direction
* of the packet. */
if( xOutgoingPacket != pdFALSE )
{
/* This is an outgoing packet. The CRC-field has been cleared. */
}
else if( ( usChecksumFound == 0U ) && ( ucProtocol == ( uint8_t ) ipPROTOCOL_UDP ) )
{
#if ( ipconfigUDP_PASS_ZERO_CHECKSUM_PACKETS == 0 )
{
/* Sender hasn't set the checksum, drop the packet because
* ipconfigUDP_PASS_ZERO_CHECKSUM_PACKETS is not set. */
usChecksum = ipWRONG_CRC;
#if ( ipconfigHAS_PRINTF != 0 )
{
static BaseType_t xCount = 0;
/* Exclude this from branch coverage as this is only used for debugging. */
if( xCount < 5 ) /* LCOV_EXCL_BR_LINE */
{
FreeRTOS_printf( ( "usGenerateProtocolChecksum: UDP packet from %xip without CRC dropped\n",
FreeRTOS_ntohl( pxIPPacket->xIPHeader.ulSourceIPAddress ) ) );
xCount++;
}
}
#endif /* ( ipconfigHAS_PRINTF != 0 ) */
}
#else /* if ( ipconfigUDP_PASS_ZERO_CHECKSUM_PACKETS == 0 ) */
{
/* Sender hasn't set the checksum, no use to calculate it. */
usChecksum = ipCORRECT_CRC;
}
#endif /* if ( ipconfigUDP_PASS_ZERO_CHECKSUM_PACKETS == 0 ) */
DEBUG_SET_TRACE_VARIABLE( xLocation, 9 );
break;
}
else
{
/* Other incoming packet than UDP. */
}
usLength = pxIPPacket->xIPHeader.usLength;
usLength = FreeRTOS_ntohs( usLength );
ulLength = ( uint32_t ) usLength;
ulLength -= ( ( uint16_t ) uxIPHeaderLength ); /* normally minus 20 */
if( ( ulLength < ( ( uint32_t ) sizeof( pxProtPack->xUDPPacket.xUDPHeader ) ) ) ||
( ulLength > ( ( uint32_t ) ipconfigNETWORK_MTU - ( uint32_t ) uxIPHeaderLength ) ) )
{
#if ( ipconfigHAS_DEBUG_PRINTF != 0 )
{
FreeRTOS_debug_printf( ( "usGenerateProtocolChecksum[%s]: len invalid: %lu\n", pcType, ulLength ) );
}
#endif /* ipconfigHAS_DEBUG_PRINTF != 0 */
/* Again, in a 16-bit return value there is no space to indicate an
* error. For incoming packets, 0x1234 will cause dropping of the packet.
* For outgoing packets, there is a serious problem with the
* format/length */
usChecksum = ipINVALID_LENGTH;
DEBUG_SET_TRACE_VARIABLE( xLocation, 10 );
break;
}
if( ucProtocol <= ( uint8_t ) ipPROTOCOL_IGMP )
{
/* ICMP/IGMP do not have a pseudo header for CRC-calculation. */
usChecksum = ( uint16_t )
( ~usGenerateChecksum( 0U,
( const uint8_t * ) &( pxProtPack->xICMPPacket.xICMPHeader ), ( size_t ) ulLength ) );
}
else
{
/* For UDP and TCP, sum the pseudo header, i.e. IP protocol + length
* fields */
usChecksum = ( uint16_t ) ( ulLength + ( ( uint16_t ) ucProtocol ) );
/* And then continue at the IPv4 source and destination addresses. */
usChecksum = ( uint16_t )
( ~usGenerateChecksum( usChecksum,
( const uint8_t * ) &( pxIPPacket->xIPHeader.ulSourceIPAddress ),
( size_t ) ( ( 2U * ( size_t ) ipSIZE_OF_IPv4_ADDRESS ) + ulLength ) ) );
/* Sum TCP header and data. */
}
if( xOutgoingPacket == pdFALSE )
{
/* This is in incoming packet. If the CRC is correct, it should be zero. */
if( usChecksum == 0U )
{
usChecksum = ( uint16_t ) ipCORRECT_CRC;
}
else
{
usChecksum = ( uint16_t ) ipWRONG_CRC;
}
}
else
{
if( ( usChecksum == 0U ) && ( ucProtocol == ( uint8_t ) ipPROTOCOL_UDP ) )
{
/* In case of UDP, a calculated checksum of 0x0000 is transmitted
* as 0xffff. A value of zero would mean that the checksum is not used. */
usChecksum = ( uint16_t ) 0xffffu;
}
}
usChecksum = FreeRTOS_htons( usChecksum );
if( xOutgoingPacket != pdFALSE )
{
switch( ucProtocol )
{
case ipPROTOCOL_UDP:
pxProtPack->xUDPPacket.xUDPHeader.usChecksum = usChecksum;
break;
case ipPROTOCOL_TCP:
pxProtPack->xTCPPacket.xTCPHeader.usChecksum = usChecksum;
break;
case ipPROTOCOL_ICMP:
pxProtPack->xICMPPacket.xICMPHeader.usChecksum = usChecksum;
break;
default: /* ipPROTOCOL_IGMP */
pxProtPack->xICMPPacket.xICMPHeader.usChecksum = usChecksum;
break;
}
usChecksum = ( uint16_t ) ipCORRECT_CRC;
}
#if ( ipconfigHAS_DEBUG_PRINTF != 0 )
else if( ( xOutgoingPacket == pdFALSE ) && ( usChecksum != ipCORRECT_CRC ) )
{
FreeRTOS_debug_printf( ( "usGenerateProtocolChecksum[%s]: ID %04X: from %lxip to %lxip bad crc: %04X\n",
pcType,
FreeRTOS_ntohs( pxIPPacket->xIPHeader.usIdentification ),
FreeRTOS_ntohl( pxIPPacket->xIPHeader.ulSourceIPAddress ),
FreeRTOS_ntohl( pxIPPacket->xIPHeader.ulDestinationIPAddress ),
FreeRTOS_ntohs( usChecksumFound ) ) );
}
else
{
/* Nothing. */
}
#endif /* ipconfigHAS_DEBUG_PRINTF != 0 */
} while( ipFALSE_BOOL );
if( ( usChecksum == ipUNHANDLED_PROTOCOL ) ||
( usChecksum == ipINVALID_LENGTH ) )
{
/* NOP if ipconfigHAS_PRINTF != 0 */
FreeRTOS_printf( ( "CRC error: %04x location %ld\n", usChecksum, xLocation ) );
}
return usChecksum;
}
/*-----------------------------------------------------------*/
/**
* This method generates a checksum for a given IPv4 header, per RFC791 (page 14).
* The checksum algorithm is described as:
* "[T]he 16 bit one's complement of the one's complement sum of all 16 bit words in the
* header. For purposes of computing the checksum, the value of the checksum field is zero."
*
* In a nutshell, that means that each 16-bit 'word' must be summed, after which
* the number of 'carries' (overflows) is added to the result. If that addition
* produces an overflow, that 'carry' must also be added to the final result. The final checksum
* should be the bitwise 'not' (ones-complement) of the result if the packet is
* meant to be transmitted, but this method simply returns the raw value, probably
* because when a packet is received, the checksum is verified by checking that
* ((received & calculated) == 0) without applying a bitwise 'not' to the 'calculated' checksum.
*
* This logic is optimized for microcontrollers which have limited resources, so the logic looks odd.
* It iterates over the full range of 16-bit words, but it does so by processing several 32-bit
* words at once whenever possible. Its first step is to align the memory pointer to a 32-bit boundary,
* after which it runs a fast loop to process multiple 32-bit words at once and adding their 'carries'.
* Finally, it finishes up by processing any remaining 16-bit words, and adding up all of the 'carries'.
* With 32-bit arithmetic, the number of 16-bit 'carries' produced by sequential additions can be found
* by looking at the 16 most-significant bits of the 32-bit integer, since a 32-bit int will continue
* counting up instead of overflowing after 16 bits. That is why the actual checksum calculations look like:
* union.u32 = ( uint32_t ) union.u16[ 0 ] + union.u16[ 1 ];
*
* Arguments:
* ulSum: This argument provides a value to initialise the progressive summation
* of the header's values to. It is often 0, but protocols like TCP or UDP
* can have pseudo-header fields which need to be included in the checksum.
* pucNextData: This argument contains the address of the first byte which this
* method should process. The method's memory iterator is initialised to this value.
* uxDataLengthBytes: This argument contains the number of bytes that this method
* should process.
*/
/**
* @brief Calculates the 16-bit checksum of an array of bytes
*
* @param[in] usSum: The initial sum, obtained from earlier data.
* @param[in] pucNextData: The actual data.
* @param[in] uxByteCount: The number of bytes.
*
* @return The 16-bit one's complement of the one's complement sum of all 16-bit
* words in the header
*/
uint16_t usGenerateChecksum( uint16_t usSum,
const uint8_t * pucNextData,
size_t uxByteCount )
{
/* MISRA/PC-lint doesn't like the use of unions. Here, they are a great
* aid though to optimise the calculations. */
xUnion32 xSum2;
xUnion32 xSum;
xUnion32 xTerm;
xUnionPtr xSource;
uintptr_t uxAlignBits;
uint32_t ulCarry = 0U;
uint16_t usTemp;
size_t uxDataLengthBytes = uxByteCount;
size_t uxSize;
uintptr_t ulX;
/* Small MCUs often spend up to 30% of the time doing checksum calculations
* This function is optimised for 32-bit CPUs; Each time it will try to fetch
* 32-bits, sums it with an accumulator and counts the number of carries. */
/* Swap the input (little endian platform only). */
usTemp = FreeRTOS_ntohs( usSum );
xSum.u32 = ( uint32_t ) usTemp;
xTerm.u32 = 0U;
xSource.u8ptr = pucNextData;
/* MISRA Ref 11.4.3 [Casting pointer to int for verification] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-114 */
/* coverity[misra_c_2012_rule_11_4_violation] */
uxAlignBits = ( ( ( uintptr_t ) pucNextData ) & 0x03U );
/*
* If pucNextData is non-aligned then the checksum is starting at an
* odd position and we need to make sure the usSum value now in xSum is
* as if it had been "aligned" in the same way.
*/
if( ( uxAlignBits & 1U ) != 0U )
{
xSum.u32 = ( ( xSum.u32 & 0xffU ) << 8 ) | ( ( xSum.u32 & 0xff00U ) >> 8 );
}
/* If byte (8-bit) aligned... */
if( ( ( uxAlignBits & 1U ) != 0U ) && ( uxDataLengthBytes >= ( size_t ) 1U ) )
{
xTerm.u8[ 1 ] = *( xSource.u8ptr );
xSource.u8ptr++;
uxDataLengthBytes--;
/* Now xSource is word (16-bit) aligned. */
}
/* If half-word (16-bit) aligned... */
if( ( ( uxAlignBits == 1U ) || ( uxAlignBits == 2U ) ) && ( uxDataLengthBytes >= 2U ) )
{
xSum.u32 += *( xSource.u16ptr );
xSource.u16ptr++;
uxDataLengthBytes -= 2U;
/* Now xSource is word (32-bit) aligned. */
}
/* Word (32-bit) aligned, do the most part. */
uxSize = ( size_t ) ( ( uxDataLengthBytes / 4U ) * 4U );
if( uxSize >= ( 3U * sizeof( uint32_t ) ) )
{
uxSize -= ( 3U * sizeof( uint32_t ) );
}
else
{
uxSize = 0U;
}
/* In this loop, four 32-bit additions will be done, in total 16 bytes.
* Indexing with constants (0,1,2,3) gives faster code than using
* post-increments. */
for( ulX = 0U; ulX < uxSize; ulX += 4U * sizeof( uint32_t ) )
{
/* Use a secondary Sum2, just to see if the addition produced an
* overflow. */
xSum2.u32 = xSum.u32 + xSource.u32ptr[ 0 ];
if( xSum2.u32 < xSum.u32 )
{
ulCarry++;
}
/* Now add the secondary sum to the major sum, and remember if there was
* a carry. */
xSum.u32 = xSum2.u32 + xSource.u32ptr[ 1 ];
if( xSum2.u32 > xSum.u32 )
{
ulCarry++;
}
/* And do the same trick once again for indexes 2 and 3 */
xSum2.u32 = xSum.u32 + xSource.u32ptr[ 2 ];
if( xSum2.u32 < xSum.u32 )
{
ulCarry++;
}
xSum.u32 = xSum2.u32 + xSource.u32ptr[ 3 ];
if( xSum2.u32 > xSum.u32 )
{
ulCarry++;
}
/* And finally advance the pointer 4 * 4 = 16 bytes. */
xSource.u32ptr = &( xSource.u32ptr[ 4 ] );
}
/* Now add all carries. */
xSum.u32 = ( uint32_t ) xSum.u16[ 0 ] + xSum.u16[ 1 ] + ulCarry;
uxDataLengthBytes %= 16U;
/* Half-word aligned. */
uxSize = ( ( uxDataLengthBytes & ~( ( size_t ) 1U ) ) );
for( ulX = 0U; ulX < uxSize; ulX += 1U * sizeof( uint16_t ) )
{
/* At least one more short. */
xSum.u32 += xSource.u16ptr[ 0 ];
xSource.u16ptr = &xSource.u16ptr[ 1 ];
}
if( ( uxDataLengthBytes & ( size_t ) 1U ) != 0U ) /* Maybe one more ? */
{
xTerm.u8[ 0 ] = xSource.u8ptr[ 0 ];
}
/* MISRA Ref 2.2.1 [Unions and dead code] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-22 */
/* coverity[misra_c_2012_rule_2_2_violation] */
/* coverity[assigned_value] */
xSum.u32 += xTerm.u32;
/* Now add all carries again. */
/* Assigning value from "xTerm.u32" to "xSum.u32" here, but that stored value is overwritten before it can be used. */
/* MISRA Ref 2.2.1 [Unions and dead code] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-22 */
/* coverity[misra_c_2012_rule_2_2_violation] */
/* coverity[value_overwrite] */
xSum.u32 = ( uint32_t ) xSum.u16[ 0 ] + xSum.u16[ 1 ];
/* MISRA Ref 2.2.1 [Unions and dead code] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-22 */
/* coverity[misra_c_2012_rule_2_2_violation] */
/* coverity[value_overwrite] */
xSum.u32 = ( uint32_t ) xSum.u16[ 0 ] + xSum.u16[ 1 ];
if( ( uxAlignBits & 1U ) != 0U )
{
/* Quite unlikely, but pucNextData might be non-aligned, which would
* mean that a checksum is calculated starting at an odd position. */
xSum.u32 = ( ( xSum.u32 & 0xffU ) << 8 ) | ( ( xSum.u32 & 0xff00U ) >> 8 );
}
/* swap the output (little endian platform only). */
return FreeRTOS_htons( ( ( uint16_t ) xSum.u32 ) );
}
/*-----------------------------------------------------------*/
#if ( ipconfigHAS_PRINTF != 0 )
#ifndef ipMONITOR_MAX_HEAP
/* As long as the heap has more space than e.g. 1 MB, there
* will be no messages. */
#define ipMONITOR_MAX_HEAP ( 1024U * 1024U )
#endif /* ipMONITOR_MAX_HEAP */
#ifndef ipMONITOR_PERCENTAGE_90
/* Make this number lower to get less logging messages. */
#define ipMONITOR_PERCENTAGE_90 ( 90U )
#endif
#define ipMONITOR_PERCENTAGE_100 ( 100U )
/**
* @brief A function that monitors a three resources: the heap, the space in the message
* queue of the IP-task, the number of available network buffer descriptors.
*/
void vPrintResourceStats( void )
{
UBaseType_t uxCurrentBufferCount;
size_t uxMinSize;
/* When setting up and testing a project with FreeRTOS+TCP, it is
* can be helpful to monitor a few resources: the number of network
* buffers and the amount of available heap.
* This function will issue some logging when a minimum value has
* changed. */
uxCurrentBufferCount = uxGetMinimumFreeNetworkBuffers();
if( uxLastMinBufferCount > uxCurrentBufferCount )
{
/* The logging produced below may be helpful
* while tuning +TCP: see how many buffers are in use. */
uxLastMinBufferCount = uxCurrentBufferCount;
FreeRTOS_printf( ( "Network buffers: %lu lowest %lu\n",
uxGetNumberOfFreeNetworkBuffers(),
uxCurrentBufferCount ) );
}
uxMinSize = xPortGetMinimumEverFreeHeapSize();
if( uxMinLastSize == 0U )
{
/* Probably the first time this function is called. */
uxMinLastSize = uxMinSize;
}
else if( uxMinSize >= ipMONITOR_MAX_HEAP )
{
/* There is more than enough heap space. No need for logging. */
}
/* Write logging if there is a 10% decrease since the last time logging was written. */
else if( ( uxMinLastSize * ipMONITOR_PERCENTAGE_90 ) > ( uxMinSize * ipMONITOR_PERCENTAGE_100 ) )
{
uxMinLastSize = uxMinSize;
FreeRTOS_printf( ( "Heap: current %lu lowest %lu\n", xPortGetFreeHeapSize(), uxMinSize ) );
}
else
{
/* Nothing to log. */
}
#if ( ipconfigCHECK_IP_QUEUE_SPACE != 0 )
{
UBaseType_t uxCurrentCount = 0u;
uxCurrentCount = uxGetMinimumIPQueueSpace();
if( uxLastMinQueueSpace != uxCurrentCount )
{
/* The logging produced below may be helpful
* while tuning +TCP: see how many buffers are in use. */
uxLastMinQueueSpace = uxCurrentCount;
FreeRTOS_printf( ( "Queue space: lowest %lu\n", uxCurrentCount ) );
}
}
#endif /* ipconfigCHECK_IP_QUEUE_SPACE */
}
#endif /* ( ipconfigHAS_PRINTF != 0 ) */
/*-----------------------------------------------------------*/
/**
* @brief Utility function: Convert error number to a human readable
* string. Declaration in FreeRTOS_errno_TCP.h.
*
* @param[in] xErrnum: The error number.
* @param[in] pcBuffer: Buffer big enough to be filled with the human readable message.
* @param[in] uxLength: Maximum length of the buffer.
*
* @return The buffer filled with human readable error string.
*/
const char * FreeRTOS_strerror_r( BaseType_t xErrnum,
char * pcBuffer,
size_t uxLength )
{
const char * pcName;
switch( xErrnum )
{
case pdFREERTOS_ERRNO_EADDRINUSE:
pcName = "EADDRINUSE";
break;
case pdFREERTOS_ERRNO_ENOMEM:
pcName = "ENOMEM";
break;
case pdFREERTOS_ERRNO_EADDRNOTAVAIL:
pcName = "EADDRNOTAVAIL";
break;
case pdFREERTOS_ERRNO_ENOPROTOOPT:
pcName = "ENOPROTOOPT";
break;
case pdFREERTOS_ERRNO_EBADF:
pcName = "EBADF";
break;
case pdFREERTOS_ERRNO_ENOSPC:
pcName = "ENOSPC";
break;
case pdFREERTOS_ERRNO_ECANCELED:
pcName = "ECANCELED";
break;
case pdFREERTOS_ERRNO_ENOTCONN:
pcName = "ENOTCONN";
break;
case pdFREERTOS_ERRNO_EINPROGRESS:
pcName = "EINPROGRESS";
break;
case pdFREERTOS_ERRNO_EOPNOTSUPP:
pcName = "EOPNOTSUPP";
break;
case pdFREERTOS_ERRNO_EINTR:
pcName = "EINTR";
break;
case pdFREERTOS_ERRNO_ETIMEDOUT:
pcName = "ETIMEDOUT";
break;
case pdFREERTOS_ERRNO_EINVAL:
pcName = "EINVAL";
break;
case pdFREERTOS_ERRNO_EWOULDBLOCK:
pcName = "EWOULDBLOCK";
break; /* same as EAGAIN */
case pdFREERTOS_ERRNO_EISCONN:
pcName = "EISCONN";
break;
default:
/* MISRA Ref 21.6.1 [snprintf and logging] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-216 */
/* coverity[misra_c_2012_rule_21_6_violation] */
( void ) snprintf( pcBuffer, uxLength, "Errno %d", ( int ) xErrnum );
pcName = NULL;
break;
}
if( pcName != NULL )
{
/* MISRA Ref 21.6.1 [snprintf and logging] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-216 */
/* coverity[misra_c_2012_rule_21_6_violation] */
( void ) snprintf( pcBuffer, uxLength, "%s", pcName );
}
if( uxLength > 0U )
{
pcBuffer[ uxLength - 1U ] = '\0';
}
return pcBuffer;
}
/*-----------------------------------------------------------*/
/**
* @brief Get the highest value of two int32's.
* @param[in] a: the first value.
* @param[in] b: the second value.
* @return The highest of the two values.
*/
int32_t FreeRTOS_max_int32( int32_t a,
int32_t b )
{
return ( a >= b ) ? a : b;
}
/*-----------------------------------------------------------*/
/**
* @brief Get the highest value of two uint32_t's.
* @param[in] a: the first value.
* @param[in] b: the second value.
* @return The highest of the two values.
*/
uint32_t FreeRTOS_max_uint32( uint32_t a,
uint32_t b )
{
return ( a >= b ) ? a : b;
}
/*-----------------------------------------------------------*/
/**
* @brief Get the highest value of two size_t's.
* @param[in] a: the first value.
* @param[in] b: the second value.
* @return The highest of the two values.
*/
size_t FreeRTOS_max_size_t( size_t a,
size_t b )
{
return ( a >= b ) ? a : b;
}
/*-----------------------------------------------------------*/
/**
* @brief Get the lowest value of two int32_t's.
* @param[in] a: the first value.
* @param[in] b: the second value.
* @return The lowest of the two values.
*/
int32_t FreeRTOS_min_int32( int32_t a,
int32_t b )
{
return ( a <= b ) ? a : b;
}
/*-----------------------------------------------------------*/
/**
* @brief Get the lowest value of two uint32_t's.
* @param[in] a: the first value.
* @param[in] b: the second value.
* @return The lowest of the two values.
*/
uint32_t FreeRTOS_min_uint32( uint32_t a,
uint32_t b )
{
return ( a <= b ) ? a : b;
}
/*-----------------------------------------------------------*/
/**
* @brief Get the lowest value of two size_t's.
* @param[in] a: the first value.
* @param[in] b: the second value.
* @return The lowest of the two values.
*/
size_t FreeRTOS_min_size_t( size_t a,
size_t b )
{
return ( a <= b ) ? a : b;
}
/*-----------------------------------------------------------*/
/**
* @brief Round-up a number to a multiple of 'd'.
* @param[in] a: the first value.
* @param[in] d: the second value.
* @return A multiple of d.
*/
uint32_t FreeRTOS_round_up( uint32_t a,
uint32_t d )
{
uint32_t ulResult = a;
configASSERT( d != 0U );
if( d != 0U )
{
ulResult = d * ( ( a + d - 1U ) / d );
}
return ulResult;
}
/*-----------------------------------------------------------*/
/**
* @brief Round-down a number to a multiple of 'd'.
* @param[in] a: the first value.
* @param[in] d: the second value.
* @return A multiple of d.
*/
uint32_t FreeRTOS_round_down( uint32_t a,
uint32_t d )
{
uint32_t ulResult = 0;
configASSERT( d != 0U );
if( d != 0U )
{
ulResult = d * ( a / d );
}
return ulResult;
}
/*-----------------------------------------------------------*/
/**
* @brief Convert character array (of size 4) to equivalent 32-bit value.
* @param[in] pucPtr: The character array.
* @return 32-bit equivalent value extracted from the character array.
*
* @note Going by MISRA rules, these utility functions should not be defined
* if they are not being used anywhere. But their use depends on the
* application and hence these functions are defined unconditionally.
*/
uint32_t ulChar2u32( const uint8_t * pucPtr )
{
return ( ( ( uint32_t ) pucPtr[ 0 ] ) << 24 ) |
( ( ( uint32_t ) pucPtr[ 1 ] ) << 16 ) |
( ( ( uint32_t ) pucPtr[ 2 ] ) << 8 ) |
( ( ( uint32_t ) pucPtr[ 3 ] ) );
}
/*-----------------------------------------------------------*/
/**
* @brief Convert character array (of size 2) to equivalent 16-bit value.
* @param[in] pucPtr: The character array.
* @return 16-bit equivalent value extracted from the character array.
*
* @note Going by MISRA rules, these utility functions should not be defined
* if they are not being used anywhere. But their use depends on the
* application and hence these functions are defined unconditionally.
*/
uint16_t usChar2u16( const uint8_t * pucPtr )
{
return ( uint16_t )
( ( ( ( uint32_t ) pucPtr[ 0 ] ) << 8 ) |
( ( ( uint32_t ) pucPtr[ 1 ] ) ) );
}
/*-----------------------------------------------------------*/