/* 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;
}
/** Register a new HGSMI channel by index.
*
* @returns VBox status.
* @param pChannelInfo The channel pool managed by the caller.
* @param u8Channel Index of the channel.
* @param pszName Name of the channel (optional, allocated by the caller).
* @param pfnChannelHandler The channel callback.
* @param pvChannelHandler The callback pointer.
*/
int HGSMIChannelRegister(HGSMICHANNELINFO *pChannelInfo,
uint8_t u8Channel,
const char *pszName,
PFNHGSMICHANNELHANDLER pfnChannelHandler,
void *pvChannelHandler)
{
/* Check whether the channel is already registered. */
HGSMICHANNEL *pChannel = HGSMIChannelFindById(pChannelInfo, u8Channel);
if (pChannel)
{
HGSMI_STRICT_ASSERT_FAILED();
return VERR_ALREADY_EXISTS;
}
/* Channel is not yet registered. */
pChannel = &pChannelInfo->Channels[u8Channel];
pChannel->u8Flags = HGSMI_CH_F_REGISTERED;
pChannel->u8Channel = u8Channel;
pChannel->handler.pfnHandler = pfnChannelHandler;
pChannel->handler.pvHandler = pvChannelHandler;
pChannel->pszName = pszName;
return VINF_SUCCESS;
}
/** Process a guest buffer.
*
* @returns VBox status.
* @param pArea Area which supposed to contain the buffer.
* @param pChannelInfo The channel pool.
* @param offBuffer The buffer location in the area.
*/
int HGSMIBufferProcess(const HGSMIAREA *pArea,
HGSMICHANNELINFO *pChannelInfo,
HGSMIOFFSET offBuffer)
{
LogFlowFunc(("pArea %p, offBuffer 0x%x\n", pArea, offBuffer));
AssertPtrReturn(pArea, VERR_INVALID_PARAMETER);
AssertPtrReturn(pChannelInfo, VERR_INVALID_PARAMETER);
/* Guest has prepared a command description at 'offBuffer'. */
HGSMIBUFFERCONTEXT bufferContext;
int rc = hgsmiVerifyBuffer(pArea, offBuffer, &bufferContext);
if (RT_SUCCESS(rc))
{
/* Pass the command to the appropriate handler registered with this instance.
* Start with the handler list head, which is the preallocated HGSMI setup channel.
*/
const HGSMICHANNEL *pChannel = HGSMIChannelFindById(pChannelInfo, bufferContext.pHeader->u8Channel);
if (pChannel)
{
const HGSMICHANNELHANDLER *pHandler = &pChannel->handler;
if (pHandler->pfnHandler)
{
pHandler->pfnHandler(pHandler->pvHandler, bufferContext.pHeader->u16ChannelInfo,
bufferContext.pvData, bufferContext.cbData);
}
HGSMI_STRICT_ASSERT(RT_SUCCESS(hgsmiVerifyBuffer(pArea, offBuffer, &bufferContext)));
}
else
{
rc = VERR_INVALID_FUNCTION;
HGSMI_STRICT_ASSERT_FAILED();
}
}
return rc;
}
/** 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;
}
