BYTE Snmpv3AuthenticateTxPduForDataIntegrity(SNMPV3_RESPONSE_WHOLEMSG* txDataPtr)
{
UINT8* secNamePtr;
UINT8 i;
static HASH_SUM md5;
UINT8* tempPtr;
UINT8 hashTYpe;
hashTYpe=snmpV3UserDataBase[gSnmpv3UserDBIndex].userHashType;
if(hashTYpe == SNMPV3_HAMC_MD5)
{
MD5Initialize(&md5);
MD5AddData(&md5,snmpV3UserDataBase[gSnmpv3UserDBIndex].userAuthLocalKeyHmacIpad, (WORD)0x40);
MD5AddData(&md5, txDataPtr->wholeMsgHead, txDataPtr->wholeMsgLen.Val);
MD5Calculate(&md5, HmacMd5Digest);
MD5Initialize(&md5);
MD5AddData(&md5, snmpV3UserDataBase[gSnmpv3UserDBIndex].userAuthLocalKeyHmacOpad, (WORD)0x40);
MD5AddData(&md5, HmacMd5Digest,16);
MD5Calculate(&md5, HmacMd5Digest);
}
else if(hashTYpe == SNMPV3_HMAC_SHA1)
{
SHA1Initialize(&md5);
SHA1AddData(&md5,snmpV3UserDataBase[gSnmpv3UserDBIndex].userAuthLocalKeyHmacIpad, (WORD)0x40);
SHA1AddData(&md5, txDataPtr->wholeMsgHead, txDataPtr->wholeMsgLen.Val);
SHA1Calculate(&md5, HmacSHADigest);
SHA1Initialize(&md5);
SHA1AddData(&md5, snmpV3UserDataBase[gSnmpv3UserDBIndex].userAuthLocalKeyHmacOpad, (WORD)0x40);
SHA1AddData(&md5, HmacSHADigest,20);
SHA1Calculate(&md5, HmacSHADigest);
}
else
return SNMPV3_MSG_AUTH_FAIL ;
//Authparam validated on WholeMsg. Write back the auth param string to received buffer
tempPtr=snmpOutMsgAuthParamStrng;
if(hashTYpe == SNMPV3_HAMC_MD5)
secNamePtr=HmacMd5Digest;
else if(hashTYpe == SNMPV3_HMAC_SHA1)
secNamePtr=HmacSHADigest;
i=0;
for(i=0;i < 12/*snmpOutMsgAuthParamLen Should be 12 Bytes*/;i++)
{
tempPtr[i]=secNamePtr[i];
}
return SNMPV3_MSG_AUTH_PASS;
}
/****************************************************************************
Function:
static void SNMPv3PswdToLocalizedAuthKeyMD5Hashing(UINT8* pswdToLocalized, UINT8 pswdLen)
Summary:
Convert MD5 Auth password to the localized Key using SNMPEngineID.
Description:
This routine converts HMAC-MD5 authentication password key
to localized key using snmpSngineID(RFC- 3414).
Precondition:
SNMPv3Init() and ProcessVariabels() are called.
Parameters:
pswdToLocalized - password storage poniter
pswdLen - password length.
Return Values:
None
Remarks:
None
***************************************************************************/
static void SNMPv3PswdToLocalizedAuthKeyMD5Hashing(uint8_t* pswdToLocalized, uint8_t pswdLen)
{
static HASH_SUM md5;
uint8_t *compressionPtr, pswdBuf[64];
uint32_t index = 0;
uint32_t count = 0, i;
uint8_t* pswdPtr;
SNMPV3_PROCESSING_MEM_INFO_PTRS snmpv3PktProcessingMemPntr;
SNMPV3_STACK_DCPT_STUB * snmpv3EngnDcptMemoryStubPtr=0;
SNMPv3GetPktProcessingDynMemStubPtrs(&snmpv3PktProcessingMemPntr);
snmpv3EngnDcptMemoryStubPtr=snmpv3PktProcessingMemPntr.snmpv3StkProcessingDynMemStubPtr;
pswdPtr=pswdToLocalized;
MD5Initialize(&md5);
while (count < 1048576)
{
compressionPtr = pswdBuf;
for (i = 0; i < 64; i++)
{
*compressionPtr++ = pswdPtr[index++ % pswdLen];
}
MD5AddData(&md5, pswdBuf, 64);
count+=64;
}
MD5Calculate(&md5, md5LocalizedAuthKey);
memcpy(pswdBuf, md5LocalizedAuthKey, 16 /*localizedAuthKey buf len*/);
memcpy(pswdBuf+16, snmpv3EngnDcptMemoryStubPtr->SnmpEngineID, snmpv3EngnDcptMemoryStubPtr->SnmpEngnIDLength);
memcpy(pswdBuf+16+snmpv3EngnDcptMemoryStubPtr->SnmpEngnIDLength, md5LocalizedAuthKey, 16 /*localizedAuthKey buf len*/);
MD5Initialize(&md5);
MD5AddData(&md5,pswdBuf,32+snmpv3EngnDcptMemoryStubPtr->SnmpEngnIDLength);
MD5Calculate(&md5, md5LocalizedAuthKey);
count+=64;
return;
}
/*****************************************************************************
Function:
void HashAddData(HASH_SUM* theSum, BYTE* data, WORD len)
Description:
Adds data to the hash sum.
Precondition:
The hash sum has already been initialized
Parameters:
theSum - hash context state
data - the data to be added to the hash sum
len - length of data
Returns:
None
Remarks:
This function calls the appropriate hashing function based on the
hash typed defined in theSum.
***************************************************************************/
void HashAddData(HASH_SUM* theSum, BYTE* data, WORD len)
{
#if defined(STACK_USE_MD5)
if(theSum->hashType == HASH_MD5)
MD5AddData(theSum, data, len);
#endif
#if defined(STACK_USE_SHA1)
if(theSum->hashType == HASH_SHA1)
SHA1AddData(theSum, data, len);
#endif
}
void Snmpv3Pswd2LocalizedAuthKeyMD5Hashing(UINT8* pswdToLocalized, UINT8 pswdLen)
{
static HASH_SUM md5;
UINT8 *compressionPtr, pswdBuf[64];
UINT32 index = 0;
UINT32 count = 0, i;
UINT8* pswdPtr;
pswdPtr=pswdToLocalized;
MD5Initialize(&md5);
while (count < 1048576)
{
compressionPtr = pswdBuf;
for (i = 0; i < 64; i++)
{
*compressionPtr++ = pswdPtr[index++ % pswdLen];
}
MD5AddData(&md5, pswdBuf, 64);
count+=64;
}
MD5Calculate(&md5, md5LocalizedAuthKey);
memcpy(pswdBuf, md5LocalizedAuthKey, 16 /*localizedAuthKey buf len*/);
memcpy(pswdBuf+16, snmpEngineID, snmpEngnIDLength);
memcpy(pswdBuf+16+snmpEngnIDLength, md5LocalizedAuthKey, 16 /*localizedAuthKey buf len*/);
MD5Initialize(&md5);
MD5AddData(&md5,pswdBuf,32+snmpEngnIDLength);
MD5Calculate(&md5, md5LocalizedAuthKey);
count+=64;
return;
}
UINT8* Snmpv3ComputeHmacMD5Digest(UINT8 * inData, UINT32 dataLen,UINT8* userExtendedLclzdKeyIpad,UINT8* userExtendedLclzdKeyOpad)
{
static HASH_SUM md5;
UINT8 * data2Hmac;
data2Hmac=inData;
MD5Initialize(&md5);
MD5AddData(&md5, userExtendedLclzdKeyIpad, (WORD)0x40);
MD5AddData(&md5, data2Hmac, (WORD)dataLen);
MD5Calculate(&md5, HmacMd5Digest);
MD5Initialize(&md5);
MD5AddData(&md5, userExtendedLclzdKeyOpad, (WORD)0x40);
MD5AddData(&md5, HmacMd5Digest,16);
MD5Calculate(&md5, HmacMd5Digest);
return HmacMd5Digest;
}
/****************************************************************************
Function:
static unit_8* SNMPv3ComputeHmacMD5Digest(UINT8 * inData, UINT32 dataLen,
UINT8* userExtendedLclzdKeyIpad,
UINT8* userExtendedLclzdKeyOpad)
Summary:
Compute HMAC - MD5 authentication code
Description:
This routine supports data origin authentication and data integrity MD5 authentication .
Both iPAD and OPAD is used to calculate the authencate digest string.
RFC - 3414 ( section 6)
Precondition:
SNMPv3Init() and ProcessVariabels() are called.
Parameters:
digestptr - output string
indata - input data
dataLen - input data length
userExtendedLclzdKeyIpad - IPAD
userExtendedLclzdKeyOpad - OPAD
Return Values:
UINT8 * - HMAC MD5 digest string
Remarks:
None
***************************************************************************/
static uint8_t* SNMPv3ComputeHmacMD5Digest(uint8_t * inData, uint32_t dataLen,uint8_t* userExtendedLclzdKeyIpad,uint8_t* userExtendedLclzdKeyOpad)
{
static HASH_SUM md5;
uint8_t * data2Hmac;
data2Hmac=inData;
MD5Initialize(&md5);
MD5AddData(&md5, userExtendedLclzdKeyIpad, (uint16_t)0x40);
MD5AddData(&md5, data2Hmac, (uint16_t)dataLen);
MD5Calculate(&md5, HmacMd5Digest);
MD5Initialize(&md5);
MD5AddData(&md5, userExtendedLclzdKeyOpad, (uint16_t)0x40);
MD5AddData(&md5, HmacMd5Digest,16);
MD5Calculate(&md5, HmacMd5Digest);
return HmacMd5Digest;
}
/****************************************************************************
Function:
BYTE Snmpv3AuthenticateRxedPduForDataIntegrity(SNMPV3_REQUEST_WHOLEMSG* rxDataPtr)
Summary:
Authenticate an incoming SNMPV3 USM PDU using MD5 or SHA
Description:
This routine authenticates SNMPV3 incoming report PDU message and also for different
type of GET requests with both MD5 and SHA protocol.If the received PDU username is
similar to "initial", then there shoud be report PDU.
RFC - 3414.
Precondition:
SNMPv3Init() and ProcessVariabels() are called.
Parameters:
rxDataPtr - incoming PDU
Return Values:
SNMPV3_MSG_AUTH_PASS - Authentication success
SNMPV3_MSG_AUTH_FAIL - Authentication failure
Remarks:
None
***************************************************************************/
BYTE Snmpv3AuthenticateRxedPduForDataIntegrity(SNMPV3_REQUEST_WHOLEMSG* rxDataPtr)
{
UINT8 reportMsgName[7]="initial";//respose is "report" 0xa8 msg
UINT8* secNamePtr;
UINT8 i;
WORD authParamOffset;
UINT8 hashTYpe;
static HASH_SUM md5;
UINT8* tempPtr;
secNamePtr= securityPrimitivesOfIncomingPdu.securityName;
hashTYpe=snmpV3UserDataBase[gSnmpv3UserDBIndex].userHashType;
//Check if the received packet is expecting "report" as response.
if(!strncmp((const char *)secNamePtr,
(const char *)reportMsgName,
(securityPrimitivesOfIncomingPdu.securityNameLength)))
return FALSE; //If "report" is expected, Retrun.
authParamOffset=gSnmpV3InPduWholeMsgBuf.msgAuthParamOffsetInWholeMsg;
tempPtr=gSnmpV3InPduWholeMsgBuf.snmpMsgHead;
for(i=0;i<snmpInMsgAuthParamLen /*Should be 12 Bytes*/;i++)
{
//RFC3414 Section 6.3.2 Page#56 Step3
*(tempPtr+authParamOffset+i)=0x00;
}
if(hashTYpe == SNMPV3_HAMC_MD5)
{
MD5Initialize(&md5);
MD5AddData(&md5,snmpV3UserDataBase[gSnmpv3UserDBIndex].userAuthLocalKeyHmacIpad, (WORD)0x40);
MD5AddData(&md5, rxDataPtr->wholeMsgHead, rxDataPtr->wholeMsgLen.Val);
MD5Calculate(&md5, HmacMd5Digest);
MD5Initialize(&md5);
MD5AddData(&md5, snmpV3UserDataBase[gSnmpv3UserDBIndex].userAuthLocalKeyHmacOpad, (WORD)0x40);
MD5AddData(&md5, HmacMd5Digest,16);
MD5Calculate(&md5, HmacMd5Digest);
}
else if(hashTYpe == SNMPV3_HMAC_SHA1)
{
SHA1Initialize(&md5);
SHA1AddData(&md5,snmpV3UserDataBase[gSnmpv3UserDBIndex].userAuthLocalKeyHmacIpad, (WORD)0x40);
SHA1AddData(&md5, rxDataPtr->wholeMsgHead, rxDataPtr->wholeMsgLen.Val);
SHA1Calculate(&md5, HmacSHADigest);
SHA1Initialize(&md5);
SHA1AddData(&md5, snmpV3UserDataBase[gSnmpv3UserDBIndex].userAuthLocalKeyHmacOpad, (WORD)0x40);
SHA1AddData(&md5, HmacSHADigest,20);
SHA1Calculate(&md5, HmacSHADigest);
//return TRUE;
}
else
return SNMPV3_MSG_AUTH_FAIL ;
if(hashTYpe == SNMPV3_HAMC_MD5)
{
i=strncmp((const char *)&snmpInMsgAuthParamStrng,(const char *)&HmacMd5Digest,12);
}
else if(hashTYpe == SNMPV3_HMAC_SHA1)
{
i=strncmp((const char *)&snmpInMsgAuthParamStrng,(const char *)&HmacSHADigest,12);
}
if(i!=0)
return SNMPV3_MSG_AUTH_FAIL;
//Authparam validated on WholeMsg. Write back the auth param string to received buffer
tempPtr=gSnmpV3InPduWholeMsgBuf.snmpMsgHead;
for(i=0;i<snmpInMsgAuthParamLen /*Should be 12 Bytes*/;i++)
{
*(tempPtr+authParamOffset+i)=snmpInMsgAuthParamStrng[i];
}
return SNMPV3_MSG_AUTH_PASS;
}
/****************************************************************************
Function:
BYTE SNMPv3AuthenticateTxPduForDataIntegrity(SNMPV3_RESPONSE_WHOLEMSG* txDataPtr)
Summary:
Authenticate to an outgoing SNMPV3 USM PDU using MD5 or SHA
Description:
This routine authenticates SNMPV3 outgoing report PDU message and also for GET
Response PDU for whole message.
RFC - 3414.
Precondition:
SNMPv3Init() and ProcessVariabels() are called.
Parameters:
txDataPtr - outgoing PDU
Return Values:
SNMPV3_MSG_AUTH_PASS - Authentication success
SNMPV3_MSG_AUTH_FAIL - Authentication failure
Remarks:
None
***************************************************************************/
uint8_t SNMPv3AuthenticateTxPduForDataIntegrity(SNMPV3_RESPONSE_WHOLEMSG* txDataPtr)
{
uint8_t* secNamePtr;
uint8_t i;
static HASH_SUM md5;
uint8_t* tempPtr;
uint8_t hashTYpe;
SNMPV3_PROCESSING_MEM_INFO_PTRS snmpv3PktProcessingMemPntr;
SNMPV3_STACK_DCPT_STUB * snmpv3EngnDcptMemoryStubPtr=0;
SNMPv3GetPktProcessingDynMemStubPtrs(&snmpv3PktProcessingMemPntr);
snmpv3EngnDcptMemoryStubPtr=snmpv3PktProcessingMemPntr.snmpv3StkProcessingDynMemStubPtr;
hashTYpe=snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userHashType;
if(hashTYpe == SNMPV3_HAMC_MD5)
{
MD5Initialize(&md5);
MD5AddData(&md5,snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userAuthLocalKeyHmacIpad, (uint16_t)0x40);
MD5AddData(&md5, txDataPtr->wholeMsgHead, txDataPtr->wholeMsgLen.Val);
MD5Calculate(&md5, HmacMd5Digest);
MD5Initialize(&md5);
MD5AddData(&md5, snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userAuthLocalKeyHmacOpad, (uint16_t)0x40);
MD5AddData(&md5, HmacMd5Digest,16);
MD5Calculate(&md5, HmacMd5Digest);
}
else if(hashTYpe == SNMPV3_HMAC_SHA1)
{
SHA1Initialize(&md5);
SHA1AddData(&md5,snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userAuthLocalKeyHmacIpad, (uint16_t)0x40);
SHA1AddData(&md5, txDataPtr->wholeMsgHead, txDataPtr->wholeMsgLen.Val);
SHA1Calculate(&md5, HmacSHADigest);
SHA1Initialize(&md5);
SHA1AddData(&md5, snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userAuthLocalKeyHmacOpad, (uint16_t)0x40);
SHA1AddData(&md5, HmacSHADigest,20);
SHA1Calculate(&md5, HmacSHADigest);
}
else
return SNMPV3_MSG_AUTH_FAIL ;
//Authparam validated on WholeMsg. Write back the auth param string to received buffer
tempPtr=snmpv3EngnDcptMemoryStubPtr->SnmpOutMsgAuthParaStrng;
if(hashTYpe == SNMPV3_HAMC_MD5)
secNamePtr=HmacMd5Digest;
else if(hashTYpe == SNMPV3_HMAC_SHA1)
secNamePtr=HmacSHADigest;
i=0;
for(i=0;i < 12/*SnmpOutMsgAuthParmLen Should be 12 Bytes*/;i++)
{
tempPtr[i]=secNamePtr[i];
}
return SNMPV3_MSG_AUTH_PASS;
}
/****************************************************************************
Function:
BYTE SNMPv3AuthenticateRxedPduForDataIntegrity(SNMPV3_REQUEST_WHOLEMSG* rxDataPtr)
Summary:
Authenticate an incoming SNMPV3 USM PDU using MD5 or SHA
Description:
This routine authenticates SNMPV3 incoming report PDU message and also for different
type of GET requests with both MD5 and SHA protocol.If the received PDU username is
similar to "initial", then there shoud be report PDU.
RFC - 3414.
Precondition:
SNMPv3Init() and ProcessVariabels() are called.
Parameters:
rxDataPtr - incoming PDU
Return Values:
SNMPV3_MSG_AUTH_PASS - Authentication success
SNMPV3_MSG_AUTH_FAIL - Authentication failure
Remarks:
None
***************************************************************************/
uint8_t SNMPv3AuthenticateRxedPduForDataIntegrity(SNMPV3_REQUEST_WHOLEMSG* rxDataPtr)
{
uint8_t reportMsgName[7]="initial";//respose is "report" 0xa8 msg
uint8_t* secNamePtr;
uint8_t i;
uint16_t authParamOffset;
uint8_t hashTYpe;
static HASH_SUM md5;
uint8_t* tempPtr;
SNMPV3_PROCESSING_MEM_INFO_PTRS snmpv3PktProcessingMemPntr;
SNMPV3_STACK_DCPT_STUB * snmpv3EngnDcptMemoryStubPtr=0;
SNMPv3GetPktProcessingDynMemStubPtrs(&snmpv3PktProcessingMemPntr);
snmpv3EngnDcptMemoryStubPtr=snmpv3PktProcessingMemPntr.snmpv3StkProcessingDynMemStubPtr;
secNamePtr= snmpv3EngnDcptMemoryStubPtr->SecurtyPrimtvesOfIncmngPdu.securityName;
hashTYpe=snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userHashType;
//Check if the received packet is expecting "report" as response.
if(!strncmp((const char *)secNamePtr,
(const char *)reportMsgName,
(snmpv3EngnDcptMemoryStubPtr->SecurtyPrimtvesOfIncmngPdu.securityNameLength)))
return false; //If "report" is expected, Retrun.
authParamOffset=snmpv3EngnDcptMemoryStubPtr->InPduWholeMsgBuf.msgAuthParamOffsetInWholeMsg;
tempPtr=snmpv3EngnDcptMemoryStubPtr->InPduWholeMsgBuf.snmpMsgHead;
for(i=0;i<snmpv3EngnDcptMemoryStubPtr->SnmpInMsgAuthParamLen /*Should be 12 Bytes*/;i++)
{
//RFC3414 Section 6.3.2 Page#56 Step3
*(tempPtr+authParamOffset+i)=0x00;
}
if(hashTYpe == SNMPV3_HAMC_MD5)
{
MD5Initialize(&md5);
MD5AddData(&md5,snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userAuthLocalKeyHmacIpad, (uint16_t)0x40);
MD5AddData(&md5, rxDataPtr->wholeMsgHead, rxDataPtr->wholeMsgLen.Val);
MD5Calculate(&md5, HmacMd5Digest);
MD5Initialize(&md5);
MD5AddData(&md5, snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userAuthLocalKeyHmacOpad, (uint16_t)0x40);
MD5AddData(&md5, HmacMd5Digest,16);
MD5Calculate(&md5, HmacMd5Digest);
}
else if(hashTYpe == SNMPV3_HMAC_SHA1)
{
SHA1Initialize(&md5);
SHA1AddData(&md5,snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userAuthLocalKeyHmacIpad, (uint16_t)0x40);
SHA1AddData(&md5, rxDataPtr->wholeMsgHead, rxDataPtr->wholeMsgLen.Val);
SHA1Calculate(&md5, HmacSHADigest);
SHA1Initialize(&md5);
SHA1AddData(&md5, snmpv3EngnDcptMemoryStubPtr->UserInfoDataBase[snmpv3EngnDcptMemoryStubPtr->UserInfoDataBaseIndx].userAuthLocalKeyHmacOpad, (uint16_t)0x40);
SHA1AddData(&md5, HmacSHADigest,20);
SHA1Calculate(&md5, HmacSHADigest);
//return true;
}
else
return SNMPV3_MSG_AUTH_FAIL ;
if(hashTYpe == SNMPV3_HAMC_MD5)
{
i=strncmp((const char *)&snmpv3EngnDcptMemoryStubPtr->SnmpInMsgAuthParmStrng,(const char *)&HmacMd5Digest,12);
}
else if(hashTYpe == SNMPV3_HMAC_SHA1)
{
i=strncmp((const char *)&snmpv3EngnDcptMemoryStubPtr->SnmpInMsgAuthParmStrng,(const char *)&HmacSHADigest,12);
}
if(i!=0)
return SNMPV3_MSG_AUTH_FAIL;
//Authparam validated on WholeMsg. Write back the auth param string to received buffer
tempPtr=snmpv3EngnDcptMemoryStubPtr->InPduWholeMsgBuf.snmpMsgHead;
for(i=0;i<snmpv3EngnDcptMemoryStubPtr->SnmpInMsgAuthParamLen /*Should be 12 Bytes*/;i++)
{
*(tempPtr+authParamOffset+i)=snmpv3EngnDcptMemoryStubPtr->SnmpInMsgAuthParmStrng[i];
}
return SNMPV3_MSG_AUTH_PASS;
}