/* Verify that the given offBuffer points to a valid buffer, which is within the area.
*/
static const HGSMIBUFFERHEADER *hgsmiVerifyBuffer (const HGSMIAREA *pArea,
HGSMIOFFSET offBuffer)
{
AssertPtr(pArea);
LogFlowFunc(("buffer 0x%x, area %p %x [0x%x;0x%x]\n", offBuffer, pArea->pu8Base, pArea->cbArea, pArea->offBase, pArea->offLast));
if ( offBuffer < pArea->offBase
|| offBuffer > pArea->offLast)
{
LogFunc(("offset 0x%x is outside the area [0x%x;0x%x]!!!\n", offBuffer, pArea->offBase, pArea->offLast));
HGSMI_STRICT_ASSERT_FAILED();
return NULL;
}
const HGSMIBUFFERHEADER *pHeader = HGSMIOffsetToPointer (pArea, offBuffer);
/* Quick check of the data size, it should be less than the maximum
* data size for the buffer at this offset.
*/
LogFlowFunc(("datasize check: pHeader->u32DataSize = 0x%x pArea->offLast - offBuffer = 0x%x\n", pHeader->u32DataSize, pArea->offLast - offBuffer));
if (pHeader->u32DataSize <= pArea->offLast - offBuffer)
{
HGSMIBUFFERTAIL *pTail = HGSMIBufferTail (pHeader);
/* At least both pHeader and pTail structures are in the area. Check the checksum. */
uint32_t u32Checksum = HGSMIChecksum (offBuffer, pHeader, pTail);
LogFlowFunc(("checksum check: u32Checksum = 0x%x pTail->u32Checksum = 0x%x\n", u32Checksum, pTail->u32Checksum));
if (u32Checksum == pTail->u32Checksum)
{
LogFlowFunc(("returning %p\n", pHeader));
return pHeader;
}
else
{
LogFunc(("invalid checksum 0x%x, expected 0x%x!!!\n", u32Checksum, pTail->u32Checksum));
HGSMI_STRICT_ASSERT_FAILED();
}
}
else
{
LogFunc(("invalid data size 0x%x, maximum is 0x%x!!!\n", pHeader->u32DataSize, pArea->offLast - offBuffer));
HGSMI_STRICT_ASSERT_FAILED();
}
LogFlowFunc(("returning NULL\n"));
return NULL;
}
/* Initialize the memory buffer including its checksum.
* No changes alloed to the header and the tail after that.
*/
HGSMIOFFSET HGSMIBufferInitializeSingle(const HGSMIAREA *pArea,
HGSMIBUFFERHEADER *pHeader,
HGSMISIZE cbBuffer,
uint8_t u8Channel,
uint16_t u16ChannelInfo)
{
if ( !pArea
|| !pHeader
|| cbBuffer < HGSMIBufferMinimumSize())
{
return HGSMIOFFSET_VOID;
}
/* Buffer must be within the area:
* * header data size do not exceed the maximum data size;
* * buffer address is greater than the area base address;
* * buffer address is lower than the maximum allowed for the given data size.
*/
HGSMISIZE cbMaximumDataSize = pArea->offLast - pArea->offBase;
uint32_t u32DataSize = cbBuffer - HGSMIBufferMinimumSize();
if ( u32DataSize > cbMaximumDataSize
|| (uint8_t *)pHeader < pArea->pu8Base
|| (uint8_t *)pHeader > pArea->pu8Base + cbMaximumDataSize - u32DataSize)
{
return HGSMIOFFSET_VOID;
}
HGSMIOFFSET offBuffer = HGSMIPointerToOffset(pArea, pHeader);
pHeader->u8Flags = HGSMI_BUFFER_HEADER_F_SEQ_SINGLE;
pHeader->u32DataSize = u32DataSize;
pHeader->u8Channel = u8Channel;
pHeader->u16ChannelInfo = u16ChannelInfo;
RT_ZERO(pHeader->u.au8Union);
HGSMIBUFFERTAIL *pTail = HGSMIBufferTailFromPtr(pHeader, u32DataSize);
pTail->u32Reserved = 0;
pTail->u32Checksum = HGSMIChecksum(offBuffer, pHeader, pTail);
return offBuffer;
}
/** Verify that the given offBuffer points to a valid buffer, which is within the area.
*
* @returns VBox status and the buffer information in pBufferContext.
* @param pArea Area which supposed to contain the buffer.
* @param offBuffer The buffer location in the area.
* @param pBufferContext Where to write information about the buffer.
*/
static int hgsmiVerifyBuffer(const HGSMIAREA *pArea,
HGSMIOFFSET offBuffer,
HGSMIBUFFERCONTEXT *pBufferContext)
{
LogFlowFunc(("buffer 0x%x, area %p %x [0x%x;0x%x]\n",
offBuffer, pArea->pu8Base, pArea->cbArea, pArea->offBase, pArea->offLast));
int rc = VINF_SUCCESS;
if ( offBuffer < pArea->offBase
|| offBuffer > pArea->offLast)
{
LogFunc(("offset 0x%x is outside the area [0x%x;0x%x]!!!\n",
offBuffer, pArea->offBase, pArea->offLast));
rc = VERR_INVALID_PARAMETER;
HGSMI_STRICT_ASSERT_FAILED();
}
else
{
void *pvBuffer = HGSMIOffsetToPointer(pArea, offBuffer);
HGSMIBUFFERHEADER header = *HGSMIBufferHeaderFromPtr(pvBuffer);
/* Quick check of the data size, it should be less than the maximum
* data size for the buffer at this offset.
*/
LogFlowFunc(("datasize check: header.u32DataSize = 0x%x pArea->offLast - offBuffer = 0x%x\n",
header.u32DataSize, pArea->offLast - offBuffer));
if (header.u32DataSize <= pArea->offLast - offBuffer)
{
HGSMIBUFFERTAIL tail = *HGSMIBufferTailFromPtr(pvBuffer, header.u32DataSize);
/* At least both header and tail structures are in the area. Check the checksum. */
uint32_t u32Checksum = HGSMIChecksum(offBuffer, &header, &tail);
LogFlowFunc(("checksum check: u32Checksum = 0x%x pTail->u32Checksum = 0x%x\n",
u32Checksum, tail.u32Checksum));
if (u32Checksum == tail.u32Checksum)
{
/* Success. */
pBufferContext->pHeader = HGSMIBufferHeaderFromPtr(pvBuffer);
pBufferContext->pvData = HGSMIBufferDataFromPtr(pvBuffer);
pBufferContext->cbData = header.u32DataSize;
}
else
{
LogFunc(("invalid checksum 0x%x, expected 0x%x!!!\n",
u32Checksum, tail.u32Checksum));
rc = VERR_INVALID_STATE;
HGSMI_STRICT_ASSERT_FAILED();
}
}
else
{
LogFunc(("invalid data size 0x%x, maximum is 0x%x!!!\n",
header.u32DataSize, pArea->offLast - offBuffer));
rc = VERR_TOO_MUCH_DATA;
HGSMI_STRICT_ASSERT_FAILED();
}
}
return rc;
}
