/**
* MIT License
*
* Copyright (c) 2018 Infineon Technologies AG
*
* 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
*
*
* \file DtlsRecordLayer.c
*
* \brief This file provides APIs for the record layer functionalities.
*
* \addtogroup grOCP
* @{
*
*/
#include "optiga/common/Util.h"
#include "optiga/dtls/DtlsRecordLayer.h"
#ifdef MODULE_ENABLE_DTLS_MUTUAL_AUTH
///Default size of the window
#define DEFAULT_WINDOW_SIZE 32
/// @cond hidden
//Protocol version for DTLS 1.2
#define PROTOCOL_VERSION_1_2 0xFEFD
#define UDP_OVERHEAD 28 //20(IP Header) + 8(UDP Header)
/**
* \brief Structure to provide input to DtlsRL_CallBack_ValidateRec.
*/
typedef struct sCBValidateRec_d
{
///Record Layer
sRecordLayer_d* psRecordLayer;
///Input record
sbBlob_d* psbBlob;
///Record data
sRecordData_d* psRecordData;
}sCBValidateRec_d;
/// @endcond
/**
* \brief Validates the record header and decrypts the fragments if PpsRecData.bEncDecFlag is set
*/
_STATIC_H int32_t DtlsRL_Record_ProcessRecord(const sRecordLayer_d* PpsRecordLayer,const sbBlob_d* PpsBlobRecord,sRecordData_d* PpsRecData);
/**
* \brief Prepares a record and encrypts the fragment if PpsRecData.bEncDecFlag is set.
*/
_STATIC_H int32_t DtlsRL_Record_PrepareRecord(sRecordLayer_d* PpsRecordLayer,const sRecordData_d* PpsRecData,sbBlob_d* PpsBlobRecord);
/**
* \brief Callback to validate the record.
*/
_STATIC_H int32_t DtlsRL_CallBack_ValidateRec(const Void* PpvParams);
/**
* \brief Gets the count of the total number of record in the buffer
*/
_STATIC_H int32_t DtlsRL_GetRecordCount(uint8_t* PpbBuffer,uint16_t PwLen,uint8_t* PpbRecCount);
/**
*
* Validates the record header and decrypts the fragments if PpsRecData.bEncDecFlag is set
* Updates sRecordData_d.dwRecordInfo with information, whether the record is from
* next epoch or the current epoch.
* \param[in] PpsRecordLayer Pointer to #sRecordLayer_d structure
* \param[in] PpsBlobRecord Pointer to a blob containing record
* \param[out] PpsRecData Pointer to a blob containing processed record
*
* \retval #OCP_RL_OK Successful execution
* \retval #OCP_RL_ERROR Failure in execution
*
*/
_STATIC_H int32_t DtlsRL_Record_ProcessRecord(const sRecordLayer_d* PpsRecordLayer,const sbBlob_d* PpsBlobRecord,sRecordData_d* PpsRecData)
{
int32_t i4Status = OCP_RL_ERROR;
uint16_t wRecvFragLen;
uint16_t wServerEpoch;
sbBlob_d sBlobCipherMsg;
sbBlob_d sBlobPlainMsg;
uint8_t bContentType;
uint8_t* pbDecData = NULL;
uint16_t wInputProtVersion;
do
{
/// @cond hidden
#define MIN_DEC_PAYLOAD 17 //(1(Min 1 byte cipher text)+ 8(MAC) + 8 (Explicit nonce)))
/// @endcond
//Check for zero len blobs
if((0 == PpsBlobRecord->wLen)||(0 == PpsRecData->psBlobInOutMsg->wLen))
{
//Any error code
i4Status = (int32_t)OCP_RL_INVALID_RECORD_LENGTH;
break;
}
bContentType = PpsBlobRecord->prgbStream[OFFSET_RL_CONTENTTYPE];
wServerEpoch = Utility_GetUint16(PpsBlobRecord->prgbStream + OFFSET_RL_EPOCH);
wInputProtVersion = Utility_GetUint16(PpsBlobRecord->prgbStream + OFFSET_RL_PROT_VERSION);
//Validate protocol version
#ifdef SUPPORT_OPENSSL
//Protocol version for DTLS 1.0
#define PROTOCOL_VERSION_1_0 0xFEFF
//for Hello verify request, allow DTLS 1.2 ,1.0 as protocol version
if(*(PpsBlobRecord->prgbStream+LENGTH_RL_HEADER) == 0x03)
{
if((PROTOCOL_VERSION_1_2 != wInputProtVersion)&&(PROTOCOL_VERSION_1_0 != wInputProtVersion))
{
i4Status = (int32_t)OCP_RL_INVALID_PROTOCOL_VERSION;
break;
}
}
else
{
if(PpsRecordLayer->wTlsVersionInfo != wInputProtVersion)
{
i4Status = (int32_t)OCP_RL_INVALID_PROTOCOL_VERSION;
break;
}
}
#undef PROTOCOL_VERSION_1_0
#else
if(PpsRecordLayer->wTlsVersionInfo != wInputProtVersion)
{
i4Status = (int32_t)OCP_RL_INVALID_PROTOCOL_VERSION;
break;
}
#endif /*SUPPORT_OPENSSL*/
wRecvFragLen = Utility_GetUint16(PpsBlobRecord->prgbStream + OFFSET_RL_FRAG_LENGTH);
//Reset the flag for each record being being processed which indicates
*PpsRecordLayer->pbDec = 0x00;
if(CONTENTTYPE_CIPHER_SPEC == bContentType)
{
if((wRecvFragLen != 0x01) || ((PpsRecordLayer->wClientNextEpoch != (PpsRecordLayer->wServerEpoch+1))) || (wServerEpoch != 0x00)
|| (CONTENTTYPE_HANDSHAKE != PpsRecData->bContentType))
{
//Error since state has not changed on client side
i4Status = (int32_t)OCP_RL_BAD_RECORD;
}
else
{
PpsRecData->bContentType = bContentType;
*PpsRecordLayer->pbRecvCCSRecord = CCS_RECORD_RECV;
Utility_Memmove(PpsRecData->psBlobInOutMsg->prgbStream, PpsBlobRecord->prgbStream + OFFSET_RL_FRAGMENT, \
wRecvFragLen);
PpsRecData->psBlobInOutMsg->wLen = wRecvFragLen;
i4Status = OCP_RL_OK;
}
break;
}
else if((CONTENTTYPE_HANDSHAKE == PpsRecData->bContentType) && (CONTENTTYPE_APP_DATA == bContentType))
{
//Error, since content type is Application but no decryption
i4Status = (int32_t)OCP_RL_BAD_RECORD;
break;
}
//Is Decryption required?
else if(((ENC_DEC_ENABLED & PpsRecordLayer->bEncDecFlag)== ENC_DEC_ENABLED) &&
(wServerEpoch == PpsRecordLayer->wClientNextEpoch))
{
if(wRecvFragLen < MIN_DEC_PAYLOAD)
{
i4Status = (int32_t)OCP_RL_INVALID_DEC_PAYLOAD_LEN;
break;
}
pbDecData = (uint8_t*)OCP_MALLOC(PpsBlobRecord->wLen + OVERHEAD_UPDOWNLINK);
if(NULL == pbDecData)
{
i4Status = (int32_t)OCP_RL_MALLOC_FAILURE;
break;
}
//Copy the data to be decrypted to a offset by OVERHEAD_UPDOWNLINK bytes
Utility_Memmove((pbDecData + OVERHEAD_UPDOWNLINK), PpsBlobRecord->prgbStream, PpsBlobRecord->wLen);
//Decrypt data
sBlobCipherMsg.prgbStream = pbDecData;
sBlobCipherMsg.wLen = PpsBlobRecord->wLen + OVERHEAD_UPDOWNLINK;
sBlobPlainMsg.prgbStream = pbDecData;
sBlobPlainMsg.wLen = sBlobCipherMsg.wLen;
//Decrypt call back function
i4Status = PpsRecordLayer->fEncDecRecord(PpsRecordLayer->pEncDecArgs, &sBlobCipherMsg, &sBlobPlainMsg, PpsBlobRecord->wLen);
if(OCP_CL_OK == i4Status)
{
i4Status = OCP_RL_OK;
PpsRecData->bContentType = bContentType;
*PpsRecordLayer->pbDec = 0x01;
//Remove the record header
PpsRecData->psBlobInOutMsg->wLen = sBlobPlainMsg.wLen - LENGTH_RL_HEADER;
Utility_Memmove(PpsRecData->psBlobInOutMsg->prgbStream, sBlobPlainMsg.prgbStream + LENGTH_RL_HEADER, \
PpsRecData->psBlobInOutMsg->wLen);
}
OCP_FREE(pbDecData);
break;
}
else
{
PpsRecData->bContentType = bContentType;
//No Decryption, just copy the data
Utility_Memmove(PpsRecData->psBlobInOutMsg->prgbStream, \
PpsBlobRecord->prgbStream + OFFSET_RL_FRAGMENT, \
wRecvFragLen);
PpsRecData->psBlobInOutMsg->wLen = wRecvFragLen;
i4Status = OCP_RL_OK;
}
}while(0);
return i4Status;
}
/**
*
* Prepares a record and encrypts the fragment if PpsRecData.bEncDecFlag is set.
*
* \param[in] PpsRecordLayer Pointer to #sRecordLayer_d structure
* \param[in] PpsRecData Pointer to a blob containing processed record
* \param[in,out] PpsBlobRecord Pointer to a blob containing record
*
* \retval #OCP_RL_OK Successful execution
* \retval #OCP_RL_ERROR Failure in execution
*
*/
_STATIC_H int32_t DtlsRL_Record_PrepareRecord(sRecordLayer_d* PpsRecordLayer,const sRecordData_d* PpsRecData,sbBlob_d* PpsBlobRecord)
{
int32_t i4Status = OCP_RL_ERROR;
sbBlob_d sBlobPlainMsg;
sbBlob_d sBlobCipherMsg;
sUint64 *psClientSeqNumber;
uint16_t wClientEpoch = 0;
do
{
//Check for zero len blobs
if((0 == PpsBlobRecord->wLen)||(0 == PpsRecData->psBlobInOutMsg->wLen))
{
//Any error code
i4Status = (int32_t)OCP_RL_INVALID_RECORD_LENGTH;
break;
}
//Client as moved to new state(Change cipher spec is sent) and next state sequence number will be used
if(PpsRecordLayer->wClientNextEpoch > PpsRecordLayer->wClientEpoch)
{
psClientSeqNumber = &PpsRecordLayer->sClientNextSeqNumber;
wClientEpoch = PpsRecordLayer->wClientNextEpoch;
}
else if(PpsRecordLayer->wClientNextEpoch == PpsRecordLayer->wClientEpoch)
{
psClientSeqNumber = &PpsRecordLayer->sClientSeqNumber;
wClientEpoch = PpsRecordLayer->wClientEpoch;
}
//Client Next epoch must not be less than current client epoch
else
{
break;
}
//Add Content
PpsBlobRecord->prgbStream[0] = PpsRecData->bContentType;
//Add Protocol Version
PpsBlobRecord->prgbStream[OFFSET_RL_PROT_VERSION] = (uint8_t)(PpsRecordLayer->wTlsVersionInfo >> 8);
PpsBlobRecord->prgbStream[OFFSET_RL_PROT_VERSION+1] = (uint8_t)PpsRecordLayer->wTlsVersionInfo;
//Add Epoch
PpsBlobRecord->prgbStream[OFFSET_RL_EPOCH] = (uint8_t)(wClientEpoch >> 8);
PpsBlobRecord->prgbStream[OFFSET_RL_EPOCH + 1] = (uint8_t)wClientEpoch;
//Add Sequence Number.
if((OFFSET_RL_SEQUENCE + LENGTH_RL_SEQUENCE)>PpsBlobRecord->wLen)
{
break;
}
/// @cond hidden
#define MAX_HIGH_SEQ_NUM 0x00010000
/// @endcond
//Check for window overflow if equal max value
if((MAX_HIGH_SEQ_NUM == psClientSeqNumber->dwHigherByte) && (0x00 == psClientSeqNumber->dwLowerByte))
{
i4Status = (int32_t) OCP_RL_SEQUENCE_OVERFLOW;
break;
}
//GetUint64(&PpsRecordLayer->sClientSeqNumber,PpsBlobRecord->prgbStream+OFFSET_RL_SEQUENCE,LENGTH_RL_SEQUENCE);
Utility_SetUint16(PpsBlobRecord->prgbStream+OFFSET_RL_SEQUENCE,(uint16_t)psClientSeqNumber->dwHigherByte);
Utility_SetUint32(PpsBlobRecord->prgbStream+OFFSET_RL_SEQUENCE+2,psClientSeqNumber->dwLowerByte);
//Add Final Length
PpsBlobRecord->prgbStream[OFFSET_RL_FRAG_LENGTH] = (uint8_t)(PpsRecData->psBlobInOutMsg->wLen >> 8);
PpsBlobRecord->prgbStream[OFFSET_RL_FRAG_LENGTH+1] = (uint8_t)PpsRecData->psBlobInOutMsg->wLen;
//Is Encryption required?
if((ENC_DEC_ENABLED&PpsRecordLayer->bEncDecFlag)== ENC_DEC_ENABLED)
{
//Move the formed Record header by command lib over head(20) number of bytes
Utility_Memmove(PpsBlobRecord->prgbStream + OVERHEAD_UPDOWNLINK, PpsBlobRecord->prgbStream, LENGTH_RL_HEADER);
//Copy the data to be encrypted
Utility_Memmove(PpsBlobRecord->prgbStream + LENGTH_RL_HEADER + OVERHEAD_UPDOWNLINK,
PpsRecData->psBlobInOutMsg->prgbStream, PpsRecData->psBlobInOutMsg->wLen);
sBlobPlainMsg.prgbStream = PpsBlobRecord->prgbStream;
sBlobPlainMsg.wLen = PpsRecData->psBlobInOutMsg->wLen + LENGTH_RL_HEADER + OVERHEAD_UPDOWNLINK;
sBlobCipherMsg.prgbStream = PpsBlobRecord->prgbStream;
sBlobCipherMsg.wLen = PpsBlobRecord->wLen;
//Encrypt data
i4Status = PpsRecordLayer->fEncDecRecord(PpsRecordLayer->pEncDecArgs, &sBlobPlainMsg, &sBlobCipherMsg,
(PpsRecData->psBlobInOutMsg->wLen + LENGTH_RL_HEADER));
if(OCP_CL_OK == i4Status)
{
i4Status = OCP_RL_OK;
PpsBlobRecord->wLen = sBlobCipherMsg.wLen;
}
}
else
{
if(CONTENTTYPE_CIPHER_SPEC == PpsRecData->bContentType)
{
PpsRecordLayer->wClientNextEpoch++ ;
PpsRecordLayer->bEncDecFlag = 0xB5;
}
if(FALSE == PpsRecData->bMemoryAllocated)
{
//No encryption, just copy the data
Utility_Memmove(PpsBlobRecord->prgbStream + OFFSET_RL_FRAGMENT,
PpsRecData->psBlobInOutMsg->prgbStream,
PpsRecData->psBlobInOutMsg->wLen);
}
PpsBlobRecord->wLen = PpsRecData->psBlobInOutMsg->wLen + LENGTH_RL_HEADER;
i4Status = OCP_RL_OK;
}
//Update final length on success
if(OCP_RL_OK != i4Status)
{
PpsBlobRecord->wLen = 0;
break;
}
i4Status = IncrementUint64(psClientSeqNumber);
if(UTIL_SUCCESS == i4Status)
{
i4Status = OCP_RL_OK;
}
}while(0);
/// @cond hidden
#undef RECORDSEQ_HIGH
/// @endcond
return i4Status;
}
/**
* \brief Callback to validate the record.
*/
_STATIC_H int32_t DtlsRL_CallBack_ValidateRec(const Void* PpvParams)
{
/// @cond hidden
#define CB_PARAMS ((sCBValidateRec_d*)PpvParams)
/// @endcond
return DtlsRL_Record_ProcessRecord(CB_PARAMS->psRecordLayer,CB_PARAMS->psbBlob,CB_PARAMS->psRecordData);
/// @cond hidden
#undef CB_PARAMS
/// @endcond
}
/**
* \brief Callback to Change the server epoch state and reset the change cipher spec receive flag.
*/
_STATIC_H Void DtlsRL_CB_ChangeServerState(const Void* PpCBParams)
{
/// @cond hidden
#define S_RECORDLAYER ((sRecordLayer_d*)(((sCBStateTrn_d*)PpCBParams)->phRLHdl))
/// @endcond
S_RECORDLAYER->wServerEpoch++;
*S_RECORDLAYER->pbRecvCCSRecord = CCS_RECORD_NOTRECV;
/// @cond hidden
#undef S_RECORDLAYER
/// @endcond
}
/**
* Gets the count of the total number of record in the buffer.
*
* \param[in,out] PpbBuffer Pointer to buffer containing the records.
* \param[in] PwLen Length of the buffer.
* \param[in,out] PpbRecCount Pointer to record count value.
*
* \retval #OCP_RL_OK Successful execution
* \retval #OCP_RL_ERROR Failure in execution
*
*/
_STATIC_H int32_t DtlsRL_GetRecordCount(uint8_t* PpbBuffer,uint16_t PwLen,uint8_t* PpbRecCount)
{
int32_t i4Status = OCP_RL_ERROR;
uint8_t* pbRecPtr = PpbBuffer;
uint16_t wRemainingLen = PwLen;
uint16_t wRecLen = 0;
*PpbRecCount = 0;
do
{
//Check for remaining length
if(wRemainingLen > LENGTH_RL_HEADER)
{
//Content type check
if((*pbRecPtr != CONTENTTYPE_CIPHER_SPEC) &&
(*pbRecPtr != CONTENTTYPE_ALERT) &&
(*pbRecPtr != CONTENTTYPE_HANDSHAKE) &&
(*pbRecPtr != CONTENTTYPE_APP_DATA))
{
break;
}
//Get the record length
wRecLen = (uint32_t)Utility_GetUint16(pbRecPtr+OFFSET_RL_FRAG_LENGTH);
if((wRecLen+LENGTH_RL_HEADER) > wRemainingLen)
{
break;
}
(*PpbRecCount)++;
wRemainingLen -= (wRecLen + LENGTH_RL_HEADER);
pbRecPtr += (wRecLen + LENGTH_RL_HEADER);
i4Status = OCP_RL_OK;
}
else
{
i4Status = (int32_t)OCP_RL_OK;
break;
}
}while(TRUE);
if(0 == (*PpbRecCount))
{
i4Status = OCP_RL_ERROR;
}
return i4Status;
}
/**
* Adds record header and sends the record over the transport layer.
* Based on the input provided in PpsRecordLayer->bMemoryAllocated,the function decides whether to allocate
* memory for the record or not.
* For internal handshake implementation, memory is already allocated by Handshake layer.
* In case of Application layer, memory should be allocated here.
*
* \param[in] PpsRecordLayer Pointer to #sRecordLayer_d structure.
* \param[in] PpbData Pointer to a Data to be sent.
* \param[in] PwDataLen Pointer to length of data to be sent.
*
* \retval #OCP_RL_OK Successful execution
* \retval #OCP_RL_ERROR Failure in execution
*
*/
int32_t DtlsRL_Send(sRL_d* PpsRecordLayer,uint8_t* PpbData,uint16_t PwDataLen)
{
int32_t i4Status = OCP_RL_ERROR;
sRecordData_d sRecordData;
uint8_t* pbTotalFragMem = NULL;
uint8_t* pbEncData = NULL;
sbBlob_d sBlobData;
sbBlob_d sRecordBlobData;
/// @cond hidden
#define S_RECORDLAYER ((sRecordLayer_d*)(PpsRecordLayer->phRLHdl))
/// @endcond
do
{
//If Flight 5 is retransmitted.Reset the value to previous state
if(PpsRecordLayer->fRetransmit == TRUE)
{
S_RECORDLAYER->wClientNextEpoch--;
S_RECORDLAYER->bEncDecFlag = 0x00;
PpsRecordLayer->fRetransmit = FALSE;
}
if(TRUE == PpsRecordLayer->bMemoryAllocated)
{
//In case of Handshake
//Form struture, point to message Data
sRecordData.bContentType = PpsRecordLayer->bContentType;
sRecordData.psBlobInOutMsg = &sRecordBlobData;
sRecordData.psBlobInOutMsg->prgbStream = PpbData+LENGTH_RL_HEADER;
sRecordData.psBlobInOutMsg->wLen = PwDataLen-LENGTH_RL_HEADER;
//Client and server are in the same state.Encryption is disabled
if(S_RECORDLAYER->bEncDecFlag != ENC_DEC_ENABLED)
{
sBlobData.prgbStream = PpbData;
sBlobData.wLen = PwDataLen;
}
}
else
{
sRecordData.bContentType = PpsRecordLayer->bContentType;
sRecordData.psBlobInOutMsg = &sRecordBlobData;
sRecordData.psBlobInOutMsg->prgbStream = PpbData;
sRecordData.psBlobInOutMsg->wLen = PwDataLen;
if(S_RECORDLAYER->bEncDecFlag != ENC_DEC_ENABLED)
{
//Assign Buffer
pbTotalFragMem = (uint8_t*)OCP_MALLOC(PwDataLen + LENGTH_RL_HEADER);
if(NULL == pbTotalFragMem)
{
i4Status = (int32_t)OCP_RL_MALLOC_FAILURE;
break;
}
sBlobData.prgbStream = pbTotalFragMem;
sBlobData.wLen = PwDataLen + LENGTH_RL_HEADER;
}
}
//Client as moved to new state and encryption is enabled.Sufficient memory is allocated to store the encrypted data
if(S_RECORDLAYER->bEncDecFlag == ENC_DEC_ENABLED)
{
pbEncData = (uint8_t*)OCP_MALLOC(PwDataLen + LENGTH_RL_HEADER + MAC_LENGTH + EXPLICIT_NOUNCE_LENGTH + OVERHEAD_UPDOWNLINK);
if(NULL == pbEncData)
{
i4Status = (int32_t)OCP_RL_MALLOC_FAILURE;
break;
}
sBlobData.prgbStream = pbEncData;
sBlobData.wLen = PwDataLen + LENGTH_RL_HEADER + MAC_LENGTH + EXPLICIT_NOUNCE_LENGTH + OVERHEAD_UPDOWNLINK;
}
//Assign function pointer for encryption
S_RECORDLAYER->fEncDecRecord = PpsRecordLayer->psConfigCL->pfEncrypt;
S_RECORDLAYER->pEncDecArgs = &(PpsRecordLayer->psConfigCL->sCL);
//Add Record
sRecordData.bMemoryAllocated = PpsRecordLayer->bMemoryAllocated;
i4Status = DtlsRL_Record_PrepareRecord(S_RECORDLAYER,&sRecordData,&sBlobData);
if(OCP_RL_OK != i4Status)
{
break;
}
//Send the data over transport layer
i4Status = PpsRecordLayer->psConfigTL->pfSend(&(PpsRecordLayer->psConfigTL->sTL),
sBlobData.prgbStream,sBlobData.wLen);
if(OCP_TL_OK != i4Status)
{
break;
}
i4Status = (int32_t)OCP_RL_OK;
}while(FALSE);
if(FALSE == PpsRecordLayer->bMemoryAllocated)
{
OCP_FREE(pbTotalFragMem);
}
if(S_RECORDLAYER->bEncDecFlag == ENC_DEC_ENABLED)
{
OCP_FREE(pbEncData);
}
/// @cond hidden
#undef S_RECORDLAYER
/// @endcond
return i4Status;
}
/**
* To Slide the window to highest set sequence number.
* If Higher bound reaches a value greater than maximum possible sequence number all the bits greater than
* maximum sequence number is set to 1 in the window.
*
* \param[in,out] PpsRecordLayer Pointer to #sRL_d structure.
* \param[in] PeAuthState Indicates the state of Mutual Authentication Public Key Scheme (DTLS)
*
* \retval #OCP_RL_OK Successful execution
* \retval #OCP_RL_ERROR Failure in execution
*
*/
void Dtls_SlideWindow(const sRL_d* PpsRecordLayer, eAuthState_d PeAuthState)
{
int32_t i4Status = (int32_t)OCP_RL_OK;
uint8_t bSlideCount = 0;
uint8_t count = 0;
uint8_t bLoopCount = 1;
uint16_t wWordValue;
uint32_t dwValue;
sUint64 sBoundValue;
sWindow_d *psWindow;
/// @cond hidden
#define PS_WINDOW ((sRecordLayer_d*)(PpsRecordLayer->phRLHdl))->psWindow
#define PS_NEXTWINDOW ((sRecordLayer_d*)(PpsRecordLayer->phRLHdl))->psNextWindow
/// @endcond
do
{
/// @cond hidden
#define MAX_LOW_SEQ_NUM 0xFFFFFFFF
#define RECORDSEQ_HIGH 0xFFFF
/// @endcond
if(eAuthCompleted == PeAuthState)
{
bLoopCount = 2;
}
while(bLoopCount > 0)
{
if(bLoopCount > 1)
{
psWindow = PS_NEXTWINDOW;
}
else
{
psWindow = PS_WINDOW;
}
//If window size is 32 slide the higher word of the window
if(32 == psWindow->bWindowSize)
{
dwValue = psWindow->sWindowFrame.dwHigherByte;
//Check for highest bit which is set
while(count < 32)
{
if(LEAST_SIGNIFICANT_BIT_HIGH == (LEAST_SIGNIFICANT_BIT_HIGH & dwValue))
{
break;
}
dwValue = dwValue >> 1 ;
count++;
}
bSlideCount = psWindow->bWindowSize - count;
}
//If window size is greater then 32
if(32 < psWindow->bWindowSize)
{
//If the value of lower word is greater than zero,than highest bit is set in lower double word
if(psWindow->sWindowFrame.dwLowerByte > 0)
{
//If the value of lower double word is greater then 0xFFFF,then the highest bit is set in MSB 16 bits
if(psWindow->sWindowFrame.dwLowerByte > 0xFFFF)
{
wWordValue = psWindow->sWindowFrame.dwLowerByte >> 16;
}
//If the value of lower double word is lesser then 0xFFFF,then the highest bit is set in LSB 16 bits
else
{
bSlideCount+= 16;
wWordValue = (uint16_t)psWindow->sWindowFrame.dwLowerByte;
}
while(count < 16)
{
if(0x0001 == (wWordValue & 0x0001))
{
break;
}
wWordValue = wWordValue >> 1;
count++;
}
count = 16 - count;
bSlideCount += count ;
bSlideCount += (psWindow->bWindowSize - 32);
}
//If the value of lower word is lesser than or equal to zero,than highest bit is set in higher double word
else
{
dwValue = psWindow->sWindowFrame.dwHigherByte;
//Check for highest bit which is set
while(count < 32)
{
if(LEAST_SIGNIFICANT_BIT_HIGH == (LEAST_SIGNIFICANT_BIT_HIGH & dwValue))
{
break;
}
dwValue = dwValue >> 1 ;
count++;
}
bSlideCount = ((psWindow->bWindowSize - 32) - count);
}
}
sBoundValue.dwHigherByte = 0x00;
sBoundValue.dwLowerByte = bSlideCount;
//Set the window lower bound to the new value
i4Status = AddUint64(&psWindow->sLowerBound, &sBoundValue,&psWindow->sLowerBound);
if(UTIL_SUCCESS != i4Status)
{
break;
}
//Set the window higher bound to the new value
i4Status = AddUint64(&psWindow->sHigherBound, &sBoundValue,&psWindow->sHigherBound);
if(UTIL_SUCCESS != i4Status)
{
break;
}
//Update the window
psWindow->sWindowFrame.dwLowerByte = 0x00;
psWindow->sWindowFrame.dwHigherByte = 0x00;
//If the Higher bound is greater than maximum value of the sequence number
if(psWindow->sHigherBound.dwHigherByte > (uint32_t)RECORDSEQ_HIGH)
{
sBoundValue.dwHigherByte = RECORDSEQ_HIGH;
sBoundValue.dwLowerByte = MAX_LOW_SEQ_NUM;
//Difference of Higher bound and max sequene number
i4Status = SubtractUint64(&psWindow->sHigherBound, &sBoundValue, &sBoundValue);
if(UTIL_SUCCESS != i4Status)
{
break;
}
//If 32 bit window
if(32 == psWindow->bWindowSize)
{
psWindow->sWindowFrame.dwHigherByte = MAX_LOW_SEQ_NUM;
dwValue = 32 - sBoundValue.dwLowerByte;
while(dwValue--)
{
psWindow->sWindowFrame.dwHigherByte = psWindow->sWindowFrame.dwHigherByte >> 1;
}
}
//If window is greater than 32
else
{
psWindow->sWindowFrame.dwLowerByte = MAX_LOW_SEQ_NUM;
if(sBoundValue.dwLowerByte > 32)
{
psWindow->sWindowFrame.dwHigherByte = MAX_LOW_SEQ_NUM;
dwValue = psWindow->bWindowSize - sBoundValue.dwLowerByte;
while(dwValue--)
{
psWindow->sWindowFrame.dwHigherByte = psWindow->sWindowFrame.dwHigherByte >> 1;
}
}
else
{
dwValue = 32 - sBoundValue.dwLowerByte;
while(dwValue--)
{
psWindow->sWindowFrame.dwLowerByte = psWindow->sWindowFrame.dwLowerByte >> 1;
}
}
}
}
//Reset the count values
count = 0;
bSlideCount = 0;
dwValue = 0;
wWordValue = 0;
bLoopCount--;
}
}while(FALSE);
/// @cond hidden
#undef PS_WINDOW
#undef PS_NEXTWINDOW
#undef MAX_SEQ_NUM
#undef RECORDSEQ_HIGH
/// @endcond
}
/**
* Receives a record over transport layer, performs window check and remove the record header
* before passing back the data.
* The function also handles multiple record received in a single datagram by maintaining a count of
* number of records received.
* If the count is non-zero then a record is chosen from the given array, otherwise new record is received
* from the transport layer.
*
* \param[in] PpsRecordLayer Pointer to #sRecordLayer_d structure.
* \param[in,out] PpbBuffer Pointer to buffer to receive data.
* \param[in,out] PpwLen Pointer to variable containing buffer size and later length of received data.
*
* \retval #OCP_RL_OK Successful execution
* \retval #OCP_RL_ERROR Failure in execution
*
*/
int32_t DtlsRL_Recv(sRL_d* PpsRecordLayer,uint8_t* PpbBuffer,uint16_t* PpwLen)
{
int32_t i4Status = OCP_RL_ERROR;
sbBlob_d sbBlobCBData;
sCBValidateRec_d sCBValidateRec;
sRecordData_d sRecData;
sbBlob_d sInBlobData;
sWindow_d *psWindow;
uint16_t wServerEpoch;
/// @cond hidden
#define S_RECORDLAYER ((sRecordLayer_d*)(PpsRecordLayer->phRLHdl))
/// @endcond
do
{
//If all record not processed, do not call receive
if(0 == PpsRecordLayer->bMultipleRecord)
{
//Receive Data over Transport
i4Status = PpsRecordLayer->psConfigTL->pfRecv(&(PpsRecordLayer->psConfigTL->sTL),
PpbBuffer,PpwLen);
if((int32_t)OCP_TL_NO_DATA == i4Status)
{
i4Status = (int32_t)OCP_RL_NO_DATA;
break;
}
if(OCP_TL_OK != i4Status)
{
break;
}
if(*PpwLen > (MAX_PMTU - UDP_OVERHEAD))
{
i4Status = (int32_t)OCP_RL_INVALID_RECORD_LENGTH;
break;
}
//Check how many record are available
i4Status = DtlsRL_GetRecordCount(PpbBuffer,*PpwLen,&(PpsRecordLayer->bMultipleRecord));
if(OCP_RL_OK != i4Status)
{
break;
}
//Copy the received first record to call back input sBlob
sbBlobCBData.prgbStream = PpbBuffer;
sbBlobCBData.wLen = LENGTH_RL_HEADER;
sbBlobCBData.wLen += Utility_GetUint16(sbBlobCBData.prgbStream + OFFSET_RL_FRAG_LENGTH);
//Copy the location of the next record
PpsRecordLayer->pNextRecord = (sbBlobCBData.prgbStream + sbBlobCBData.wLen);
//Decrement the record count after a record is copied
PpsRecordLayer->bMultipleRecord--;
}
else
{
//For multiple record
////Copy the received record to call back input sBlob
sbBlobCBData.prgbStream = PpsRecordLayer->pNextRecord;
sbBlobCBData.wLen = LENGTH_RL_HEADER;
sbBlobCBData.wLen += Utility_GetUint16(sbBlobCBData.prgbStream + OFFSET_RL_FRAG_LENGTH);
//Copy the location of the next successive record
PpsRecordLayer->pNextRecord = (sbBlobCBData.prgbStream + sbBlobCBData.wLen);
//Decrement the record count after a record is copied
PpsRecordLayer->bMultipleRecord--;
}
//Assign function pointer for Decryption
S_RECORDLAYER->fEncDecRecord = PpsRecordLayer->psConfigCL->pfDecrypt;
S_RECORDLAYER->pEncDecArgs = &(PpsRecordLayer->psConfigCL->sCL);
sCBValidateRec.psRecordLayer = S_RECORDLAYER;
sCBValidateRec.psRecordData = &sRecData;
//Get message from received record
sCBValidateRec.psRecordData->bContentType = PpsRecordLayer->bContentType;
sCBValidateRec.psRecordData->psBlobInOutMsg = &sInBlobData;
sCBValidateRec.psRecordData->psBlobInOutMsg->prgbStream = PpbBuffer;
sCBValidateRec.psRecordData->psBlobInOutMsg->wLen = *PpwLen;
S_RECORDLAYER->sServerSeqNumber.dwHigherByte = (uint32_t)Utility_GetUint16 (sbBlobCBData.prgbStream + OFFSET_RL_SEQUENCE);
S_RECORDLAYER->sServerSeqNumber.dwLowerByte = Utility_GetUint32 (sbBlobCBData.prgbStream + OFFSET_RL_SEQUENCE + 2);
//Pass received Record
sCBValidateRec.psbBlob = &sbBlobCBData;
//Validate epoch
//Ignore record,If received epoch less than current epoch or
//received epoch is one greater than current epoch.
wServerEpoch = Utility_GetUint16 (sbBlobCBData.prgbStream + OFFSET_RL_EPOCH);
if((S_RECORDLAYER->wServerEpoch > wServerEpoch)||
(1 + S_RECORDLAYER->wServerEpoch) < wServerEpoch)
{
i4Status = (int32_t)OCP_RL_INCORRECT_EPOCH;
break;
}
//If epoch is one greater than current epoch and Server has not moved to new epoch
if((1 == (wServerEpoch-S_RECORDLAYER->wServerEpoch)) && (S_RECORDLAYER->wClientNextEpoch != wServerEpoch))
{
i4Status = (int32_t)OCP_RL_INCORRECT_EPOCH;
break;
}
//If the Client and server are in the same state use the current window for record sequence filtering
if(wServerEpoch == S_RECORDLAYER->wClientEpoch)
{
psWindow = S_RECORDLAYER->psWindow;
}
//If Server as moved to the new state (Change cipher spec is already sent from server) use the new window for record sequence filtering
else if(wServerEpoch == (S_RECORDLAYER->wClientEpoch + 1))
{
psWindow = S_RECORDLAYER->psNextWindow;
}
//Error if server epoch is less then client epoch
else
{
i4Status = (int32_t)OCP_RL_INCORRECT_EPOCH;
break;
}
psWindow->fValidateRecord = DtlsRL_CallBack_ValidateRec;
psWindow->pValidateArgs = (Void*)&sCBValidateRec;
psWindow->sRecvSeqNumber.dwHigherByte = S_RECORDLAYER->sServerSeqNumber.dwHigherByte;
psWindow->sRecvSeqNumber.dwLowerByte = S_RECORDLAYER->sServerSeqNumber.dwLowerByte;
i4Status = DtlsCheckReplay(psWindow);
if(((int32_t)CMD_LIB_DECRYPT_FAILURE == i4Status) || ((int32_t)OCP_RL_MALLOC_FAILURE == i4Status))
{
break;
}
else if((int32_t)OCP_RL_WINDOW_IGNORE != i4Status)
{
*PpwLen = sCBValidateRec.psRecordData->psBlobInOutMsg->wLen;
if( CONTENTTYPE_ALERT == sCBValidateRec.psRecordData->bContentType)
{
i4Status = (int32_t)OCP_RL_ALERT_RECEIVED;
}
else if(CONTENTTYPE_APP_DATA == sCBValidateRec.psRecordData->bContentType)
{
i4Status = (int32_t)OCP_RL_APPDATA_RECEIVED;
}
else
{
i4Status = (int32_t)OCP_RL_OK;
}
}
else
{
i4Status = (int32_t)OCP_RL_ERROR;
}
//if window slide refresh buffer to removed old sequence number
}while(FALSE);
/// @cond hidden
#undef S_RECORDLAYER
/// @endcond
return i4Status;
}
/**
* Initialise the DTLS Record Layer
* \param[in,out] PpsRL Pointer to #sRecordLayer_d structure.
*
* \retval #OCP_RL_OK Successful execution
* \retval #OCP_RL_ERROR Failure in execution
*
*/
int32_t DtlsRL_Init(sRL_d* PpsRL)
{
int32_t i4Status = OCP_RL_ERROR;
do
{
PpsRL->phRLHdl = (sRecordLayer_d*)OCP_MALLOC(sizeof(sRecordLayer_d));
if(NULL == PpsRL->phRLHdl)
{
i4Status = (int32_t)OCP_RL_MALLOC_FAILURE;
break;
}
memset(PpsRL->phRLHdl, 0x00, sizeof(sRecordLayer_d));
/// @cond hidden
#define S_RECORDLAYER ((sRecordLayer_d*)(PpsRL->phRLHdl))
#define PS_WINDOW (S_RECORDLAYER->psWindow)
#define PS_NEXTWINDOW (S_RECORDLAYER->psNextWindow)
/// @endcond
S_RECORDLAYER->psWindow = NULL;
S_RECORDLAYER->psNextWindow = NULL;
S_RECORDLAYER->bEncDecFlag = 0;
S_RECORDLAYER->wClientEpoch = 0;
S_RECORDLAYER->wClientNextEpoch = 0;
PpsRL->bDecRecord = 0;
PpsRL->bRecvCCSRecord = CCS_RECORD_NOTRECV;
S_RECORDLAYER->pbDec = &PpsRL->bDecRecord;
S_RECORDLAYER->pbRecvCCSRecord = &PpsRL->bRecvCCSRecord;
PpsRL->fServerStateTrn = DtlsRL_CB_ChangeServerState;
S_RECORDLAYER->wTlsVersionInfo = PROTOCOL_VERSION_1_2;//0xFE,0xFD
PpsRL->fRetransmit = FALSE;
PpsRL->bMultipleRecord = 0x00;
S_RECORDLAYER->psWindow = (sWindow_d*)OCP_MALLOC(sizeof(sWindow_d));
if(NULL == S_RECORDLAYER->psWindow)
{
i4Status = (int32_t)OCP_RL_MALLOC_FAILURE;
break;
}
memset(S_RECORDLAYER->psWindow, 0x00, sizeof(sWindow_d));
PS_WINDOW->bWindowSize = DEFAULT_WINDOW_SIZE;
PS_WINDOW->sHigherBound.dwLowerByte = PS_WINDOW->bWindowSize - 1;
PS_WINDOW->sHigherBound.dwHigherByte = 0x00;
S_RECORDLAYER->psNextWindow = (sWindow_d*)OCP_MALLOC(sizeof(sWindow_d));
if(NULL == S_RECORDLAYER->psNextWindow)
{
i4Status = (int32_t)OCP_RL_MALLOC_FAILURE;
break;
}
memset(S_RECORDLAYER->psNextWindow, 0x00, sizeof(sWindow_d));
PS_NEXTWINDOW->bWindowSize = DEFAULT_WINDOW_SIZE;
PS_NEXTWINDOW->sHigherBound.dwLowerByte = PS_WINDOW->bWindowSize - 1;
PS_NEXTWINDOW->sHigherBound.dwHigherByte = 0x00;
PS_WINDOW->fValidateRecord = NULL;
PS_WINDOW->pValidateArgs = NULL;
i4Status = OCP_RL_OK;
}while(FALSE);
/// @cond hidden
#undef S_RECORDLAYER
#undef PS_WINDOW
#undef PS_NEXTWINDOW
/// @endcond
return i4Status;
}
/**
* This function frees memory held by dtls record layer
*
* \param[in] PpsRL Pointer to the record layer structure
*
* \return None
*/
void DtlsRL_Close(sRL_d* PpsRL)
{
/// @cond hidden
#define PS_WINDOW (((sRecordLayer_d*)PpsRL->phRLHdl)->psWindow)
#define PS_NEXTWINDOW (((sRecordLayer_d*)PpsRL->phRLHdl)->psNextWindow)
/// @endcond
//NULL check
if(NULL != PpsRL)
{
if(NULL != PpsRL->phRLHdl)
{
if(NULL != PS_WINDOW)
{
//Free the allocated memory for sWindow_d structure
OCP_FREE(PS_WINDOW);
if(NULL != PS_NEXTWINDOW)
{
OCP_FREE(PS_NEXTWINDOW);
PS_NEXTWINDOW = NULL;
}
PS_WINDOW = NULL;
}
//Free the allocated memory record handle
OCP_FREE(PpsRL->phRLHdl);
PpsRL->phRLHdl = NULL;
}
}
/// @cond hidden
#undef PS_WINDOW
#undef PS_NEXTWINDOW
/// @endcond
}
/**
* @}
*/
#endif /*MODULE_ENABLE_DTLS_MUTUAL_AUTH */