int decode_authentication_request(authentication_request_msg *authentication_request, uint8_t *buffer, uint32_t len)
{
uint32_t decoded = 0;
int decoded_result = 0;
// Check if we got a NULL pointer and if buffer length is >= minimum length expected for the message.
CHECK_PDU_POINTER_AND_LENGTH_DECODER(buffer, AUTHENTICATION_REQUEST_MINIMUM_LENGTH, len);
/* Decoding mandatory fields */
if ((decoded_result = decode_u8_nas_key_set_identifier(&authentication_request->naskeysetidentifierasme, 0, *(buffer + decoded), len - decoded)) < 0)
return decoded_result;
decoded++;
if ((decoded_result = decode_authentication_parameter_rand(&authentication_request->authenticationparameterrand, 0, buffer + decoded, len - decoded)) < 0)
return decoded_result;
else
decoded += decoded_result;
if ((decoded_result = decode_authentication_parameter_autn(&authentication_request->authenticationparameterautn, 0, buffer + decoded, len - decoded)) < 0)
return decoded_result;
else
decoded += decoded_result;
return decoded;
}
int decode_security_mode_command(security_mode_command_msg *security_mode_command, uint8_t *buffer, uint32_t len)
{
uint32_t decoded = 0;
int decoded_result = 0;
// Check if we got a NULL pointer and if buffer length is >= minimum length expected for the message.
CHECK_PDU_POINTER_AND_LENGTH_DECODER(buffer, SECURITY_MODE_COMMAND_MINIMUM_LENGTH, len);
/* Decoding mandatory fields */
if ((decoded_result = decode_nas_security_algorithms(&security_mode_command->selectednassecurityalgorithms, 0, buffer + decoded, len - decoded)) < 0)
return decoded_result;
else
decoded += decoded_result;
if ((decoded_result = decode_u8_nas_key_set_identifier(&security_mode_command->naskeysetidentifier, 0, *(buffer + decoded) & 0x0f, len - decoded)) < 0)
return decoded_result;
decoded++;
if ((decoded_result = decode_ue_security_capability(&security_mode_command->replayeduesecuritycapabilities, 0, buffer + decoded, len - decoded)) < 0)
return decoded_result;
else
decoded += decoded_result;
/* Decoding optional fields */
while(len - decoded > 0)
{
uint8_t ieiDecoded = *(buffer + decoded);
/* Type | value iei are below 0x80 so just return the first 4 bits */
if (ieiDecoded >= 0x80)
ieiDecoded = ieiDecoded & 0xf0;
switch(ieiDecoded)
{
case SECURITY_MODE_COMMAND_IMEISV_REQUEST_IEI:
if ((decoded_result =
decode_imeisv_request(&security_mode_command->imeisvrequest,
SECURITY_MODE_COMMAND_IMEISV_REQUEST_IEI, buffer + decoded,
len - decoded)) <= 0)
return decoded_result;
decoded += decoded_result;
/* Set corresponding mask to 1 in presencemask */
security_mode_command->presencemask |= SECURITY_MODE_COMMAND_IMEISV_REQUEST_PRESENT;
break;
case SECURITY_MODE_COMMAND_REPLAYED_NONCEUE_IEI:
if ((decoded_result =
decode_nonce(&security_mode_command->replayednonceue,
SECURITY_MODE_COMMAND_REPLAYED_NONCEUE_IEI, buffer +
decoded, len - decoded)) <= 0)
return decoded_result;
decoded += decoded_result;
/* Set corresponding mask to 1 in presencemask */
security_mode_command->presencemask |= SECURITY_MODE_COMMAND_REPLAYED_NONCEUE_PRESENT;
break;
case SECURITY_MODE_COMMAND_NONCEMME_IEI:
if ((decoded_result =
decode_nonce(&security_mode_command->noncemme,
SECURITY_MODE_COMMAND_NONCEMME_IEI, buffer + decoded, len -
decoded)) <= 0)
return decoded_result;
decoded += decoded_result;
/* Set corresponding mask to 1 in presencemask */
security_mode_command->presencemask |= SECURITY_MODE_COMMAND_NONCEMME_PRESENT;
break;
default:
errorCodeDecoder = TLV_DECODE_UNEXPECTED_IEI;
return TLV_DECODE_UNEXPECTED_IEI;
}
}
return decoded;
}
