/**
Function to handle received ACK packet.
If the ACK number matches the expected block number, and there are more
data pending, send the next block. Otherwise tell the caller that we are done.
@param Instance The MTFTP upload session
@param Packet The MTFTP packet received
@param Len The packet length
@param Completed Return whether the upload has finished.
@retval EFI_SUCCESS The ACK is successfully processed.
@retval EFI_TFTP_ERROR The block number loops back.
@retval Others Failed to transmit the next data packet.
**/
EFI_STATUS
Mtftp4WrqHandleAck (
IN MTFTP4_PROTOCOL *Instance,
IN EFI_MTFTP4_PACKET *Packet,
IN UINT32 Len,
OUT BOOLEAN *Completed
)
{
UINT16 AckNum;
INTN Expected;
UINT64 TotalBlock;
*Completed = FALSE;
AckNum = NTOHS (Packet->Ack.Block[0]);
Expected = Mtftp4GetNextBlockNum (&Instance->Blocks);
ASSERT (Expected >= 0);
//
// Get an unwanted ACK, return EFI_SUCCESS to let Mtftp4WrqInput
// restart receive.
//
if (Expected != AckNum) {
return EFI_SUCCESS;
}
//
// Remove the acked block number, if this is the last block number,
// tell the Mtftp4WrqInput to finish the transfer. This is the last
// block number if the block range are empty..
//
Mtftp4RemoveBlockNum (&Instance->Blocks, AckNum, *Completed,&TotalBlock);
Expected = Mtftp4GetNextBlockNum (&Instance->Blocks);
if (Expected < 0) {
//
// The block range is empty. It may either because the the last
// block has been ACKed, or the sequence number just looped back,
// that is, there is more than 0xffff blocks.
//
if (Instance->LastBlock == AckNum) {
ASSERT (Instance->LastBlock >= 1);
*Completed = TRUE;
return EFI_SUCCESS;
} else {
Mtftp4SendError (
Instance,
EFI_MTFTP4_ERRORCODE_REQUEST_DENIED,
(UINT8 *) "Block number rolls back, not supported, try blksize option"
);
return EFI_TFTP_ERROR;
}
}
return Mtftp4WrqSendBlock (Instance, (UINT16) Expected);
}
/**
Deliver the received data block to the user, which can be saved
in the user provide buffer or through the CheckPacket callback.
@param Instance The Mtftp session
@param Packet The received data packet
@param Len The packet length
@retval EFI_SUCCESS The data is saved successfully
@retval EFI_ABORTED The user tells to abort by return an error through
CheckPacket
@retval EFI_BUFFER_TOO_SMALL The user's buffer is too small and buffer length is
updated to the actual buffer size needed.
**/
EFI_STATUS
Mtftp4RrqSaveBlock (
IN OUT MTFTP4_PROTOCOL *Instance,
IN EFI_MTFTP4_PACKET *Packet,
IN UINT32 Len
)
{
EFI_MTFTP4_TOKEN *Token;
EFI_STATUS Status;
UINT16 Block;
UINT64 Start;
UINT32 DataLen;
UINT64 TotalBlock;
BOOLEAN Completed;
Completed = FALSE;
Token = Instance->Token;
Block = NTOHS (Packet->Data.Block);
DataLen = Len - MTFTP4_DATA_HEAD_LEN;
//
// This is the last block, save the block no
//
if (DataLen < Instance->BlkSize) {
Completed = TRUE;
Instance->LastBlock = Block;
Mtftp4SetLastBlockNum (&Instance->Blocks, Block);
}
//
// Remove this block number from the file hole. If Mtftp4RemoveBlockNum
// returns EFI_NOT_FOUND, the block has been saved, don't save it again.
// Note that : For bigger files, allowing the block counter to roll over
// to accept transfers of unlimited size. So TotalBlock is memorised as
// continuous block counter.
//
Status = Mtftp4RemoveBlockNum (&Instance->Blocks, Block, Completed, &TotalBlock);
if (Status == EFI_NOT_FOUND) {
return EFI_SUCCESS;
} else if (EFI_ERROR (Status)) {
return Status;
}
if (Token->CheckPacket != NULL) {
Status = Token->CheckPacket (&Instance->Mtftp4, Token, (UINT16) Len, Packet);
if (EFI_ERROR (Status)) {
Mtftp4SendError (
Instance,
EFI_MTFTP4_ERRORCODE_ILLEGAL_OPERATION,
(UINT8 *) "User aborted download"
);
return EFI_ABORTED;
}
}
if (Token->Buffer != NULL) {
Start = MultU64x32 (TotalBlock - 1, Instance->BlkSize);
if (Start + DataLen <= Token->BufferSize) {
CopyMem ((UINT8 *) Token->Buffer + Start, Packet->Data.Data, DataLen);
//
// Update the file size when received the last block
//
if ((Instance->LastBlock == Block) && Completed) {
Token->BufferSize = Start + DataLen;
}
} else if (Instance->LastBlock != 0) {
//
// Don't save the data if the buffer is too small, return
// EFI_BUFFER_TOO_SMALL if received the last packet. This
// will give a accurate file length.
//
Token->BufferSize = Start + DataLen;
Mtftp4SendError (
Instance,
EFI_MTFTP4_ERRORCODE_DISK_FULL,
(UINT8 *) "User provided memory block is too small"
);
return EFI_BUFFER_TOO_SMALL;
}
}
return EFI_SUCCESS;
}
