/**RFC3320-Setction_8.4. Byte copying
From UDVM to UDVM
*/
int tcomp_udvm_bytecopy_self(tcomp_udvm_t *udvm, uint32_t *destination, uint32_t source, uint32_t tsk_size_tocopy)
{
uint32_t byte_copy_left, byte_copy_right;
//if (*destination == TCOMP_UDVM_GET_SIZE() || source == TCOMP_UDVM_GET_SIZE())
if (*destination >= TCOMP_UDVM_GET_SIZE() || source >= TCOMP_UDVM_GET_SIZE())
{
/* SEGFAULT */
tcomp_udvm_createNackInfo2(udvm, NACK_SEGFAULT);
return 0;
}
/*
* The string of bytes is copied in ascending order of memory address,
* respecting the bounds set by byte_copy_left and byte_copy_right.
*/
byte_copy_left = TCOMP_UDVM_GET_2BYTES_VAL(TCOMP_UDVM_HEADER_BYTE_COPY_LEFT_INDEX);
byte_copy_right = TCOMP_UDVM_GET_2BYTES_VAL(TCOMP_UDVM_HEADER_BYTE_COPY_RIGHT_INDEX);
// string of bytes is copied one byte at a time
while((tsk_size_tocopy--))
{
*TCOMP_UDVM_GET_BUFFER_AT((*destination)++) = *TCOMP_UDVM_GET_BUFFER_AT(source++);
*destination = (*destination == byte_copy_right)? byte_copy_left : *destination;
source = (source == byte_copy_right)? byte_copy_left : source;
}
return 1;
}
//========================================================
// UDVM machine definition
//
static tsk_object_t* tcomp_udvm_ctor(tsk_object_t * self, va_list * app)
{
tcomp_udvm_t *udvm = self;
if(udvm){
/* RFC 3320 - 7. SigComp Message Format */
udvm->sigCompMessage = va_arg(*app, tcomp_message_t *);
udvm->stateHandler = va_arg(*app, tcomp_statehandler_t *);
udvm->lpResult = va_arg(*app, tcomp_result_t *);
udvm->isOK = tsk_true;
udvm->maximum_UDVM_cycles = 0; /* RFC 3320 subclause 8.6 */
udvm->consumed_cycles = 0;
udvm->memory = tcomp_buffer_create_null();
/* Alloc UDVM memory */
if(udvm->sigCompMessage->stream_based){
/*
* If the transport is stream-based however, then a fixed-size input buffer is required to accommodate the stream, independently of the
* size of each SigComp message. So, for simplicity, the UDVM memory size is set to (decompression_memory_size / 2).
*/
tcomp_buffer_allocBuff(udvm->memory, udvm->stateHandler->sigcomp_parameters->dmsValue/2);
}
else{
/*
* If the transport is message-based then sufficient memory must be available
* to buffer the entire SigComp message before it is passed to the UDVM. So if the message is n bytes long, then the UDVM memory size is set
* to (decompression_memory_size - n), up to a maximum of 65536 bytes.
*/
tcomp_buffer_allocBuff(udvm->memory, (udvm->stateHandler->sigcomp_parameters->dmsValue-udvm->sigCompMessage->totalSize));
}
/*
* Has feedback with my state id?
*/
if(tcomp_buffer_getSize(udvm->sigCompMessage->ret_feedback_buffer)){
tsk_size_t size = tcomp_buffer_getSize(udvm->sigCompMessage->ret_feedback_buffer);
tcomp_buffer_allocBuff(udvm->lpResult->ret_feedback, size);
memcpy(tcomp_buffer_getBuffer(udvm->lpResult->ret_feedback), tcomp_buffer_getBuffer(udvm->sigCompMessage->ret_feedback_buffer), size);
}
/*
* Has state?
*/
if(tcomp_buffer_getSize(udvm->sigCompMessage->stateId)){
/* Find the provided state */
tcomp_state_t* lpState = NULL;
uint16_t match_count = tcomp_statehandler_findState(udvm->stateHandler, udvm->sigCompMessage->stateId, &lpState);
if( (!match_count || match_count>1 || !lpState)
|| (lpState->minimum_access_length > tcomp_buffer_getSize(udvm->sigCompMessage->stateId))
|| ((tsk_size_t)(lpState->address + lpState->length) > TCOMP_UDVM_GET_SIZE()) )
{
tcomp_udvm_createNackInfo(udvm, NACK_STATE_NOT_FOUND, udvm->sigCompMessage->stateId, 0);
udvm->isOK = tsk_false;
return self;
}
//this->sigCompMessage->stateId.print();//FIXME
/*
* Copy bytecodes to UDVM memory
*/
if( (tsk_size_t)(lpState->address + lpState->length) >= TCOMP_UDVM_GET_SIZE() ){
tcomp_udvm_createNackInfo2(udvm, NACK_SEGFAULT);
udvm->isOK = tsk_false;
return self;
}
memcpy( TCOMP_UDVM_GET_BUFFER_AT(lpState->address),
tcomp_buffer_getBuffer(lpState->value),
tcomp_buffer_getSize(lpState->value) );
//RFC 3320 - 7.2. Accessing Stored State (Useful values)
TCOMP_UDVM_SET_2BYTES_VAL(TCOMP_UDVM_HEADER_PARTIAL_STATE_ID_LENGTH_INDEX, tcomp_buffer_getSize(udvm->sigCompMessage->stateId));
TCOMP_UDVM_SET_2BYTES_VAL(TCOMP_UDVM_HEADER_STATE_LENGTH_INDEX, tcomp_buffer_getSize(lpState->value));
udvm->executionPointer = lpState->instruction;
}
else // DON'T HAVE STATE
{
/*
* Copy bytecodes to UDVM memory
*/
tsk_size_t bytecodes_destination = udvm->sigCompMessage->bytecodes_destination;
if( (bytecodes_destination + tcomp_buffer_getSize(udvm->sigCompMessage->uploaded_UDVM_buffer)) >= TCOMP_UDVM_GET_SIZE() ){
tcomp_udvm_createNackInfo2(udvm, NACK_BYTECODES_TOO_LARGE);
udvm->isOK = tsk_false;
return self;
}
memcpy( TCOMP_UDVM_GET_BUFFER_AT(bytecodes_destination),
tcomp_buffer_getBuffer(udvm->sigCompMessage->uploaded_UDVM_buffer),
tcomp_buffer_getSize(udvm->sigCompMessage->uploaded_UDVM_buffer));
// Set pointer indicating execution index
udvm->executionPointer = bytecodes_destination;
}
/* RFC 3320-Section_8.6. UDVM Cycles
/*
* To ensure that a SigComp message cannot consume excessive processing
* resources, SigComp limits the number of "UDVM cycles" allocated to
* each message. The number of available UDVM cycles is initialized to
* 1000 plus the number of bits in the SigComp header (as described in
* Section 7); this sum is then multiplied by cycles_per_bit.
*/
/*maximum_UDVM_cycles = (8 * n + 1000) * cycles_per_bit*///FIXME:header_size
udvm->maximum_UDVM_cycles = ( (8 * udvm->sigCompMessage->header_size + 1000)* udvm->stateHandler->sigcomp_parameters->cpbValue );
//
// RFC 3320 - 7.2. Useful values
//
TCOMP_UDVM_SET_2BYTES_VAL(TCOMP_UDVM_HEADER_UDVM_MEMORY_SIZE_INDEX, TCOMP_UDVM_GET_SIZE());
TCOMP_UDVM_SET_2BYTES_VAL(TCOMP_UDVM_HEADER_CYCLES_PER_BIT_INDEX, udvm->stateHandler->sigcomp_parameters->cpbValue);
TCOMP_UDVM_SET_2BYTES_VAL(TCOMP_UDVM_HEADER_SIGCOMP_VERSION_INDEX, udvm->stateHandler->sigcomp_parameters->SigComp_version);
memset(TCOMP_UDVM_GET_BUFFER_AT(TCOMP_UDVM_HEADER_RESERVED_INDEX), 0, TCOMP_UDVM_HEADER_RESERVED_SIZE);
}
else{
