/*++
Copyright (c) 1998-2001 Microsoft Corporation
Module Name:
kd1394io.c
Abstract:
1394 Kernel Debugger DLL
Author:
George Chrysanthakopoulos (georgioc) Nov-1999
Revision History:
Date Who What
---------- --------- ------------------------------------------------------------
06/19/2001 pbinder cleanup
--*/
#define _KD1394IO_C
#include "pch.h"
#undef _KD1394IO_C
#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGEKD, KdpComputeChecksum)
#pragma alloc_text(PAGEKD, KdpSendControlPacket)
#pragma alloc_text(PAGEKD, KdReceivePacket)
#pragma alloc_text(PAGEKD, KdSendPacket)
#endif
//
// KdpRetryCount controls the number of retries before we give
// up and assume kernel debugger is not present.
// KdpNumberRetries is the number of retries left. Initially,
// it is set to 5 such that booting NT without debugger won't be
// delayed to long.
//
ULONG KdCompNumberRetries = 5;
ULONG KdCompRetryCount = 5;
ULONG KdPacketId = 0;
ULONG
KdpComputeChecksum(
IN PUCHAR Buffer,
IN ULONG Length
)
/*++
Routine Description:
This routine computes the checksum for the string passed in.
Arguments:
Buffer - Supplies a pointer to the string.
Length - Supplies the length of the string.
Return Value:
A ULONG is return as the checksum for the input string.
--*/
{
ULONG Checksum = 0;
while (Length > 0) {
Checksum = Checksum + (ULONG)*Buffer++;
Length--;
}
return(Checksum);
} // KdpComputeChecksum
void
KdpSendControlPacket(
IN USHORT PacketType,
IN ULONG PacketId OPTIONAL
)
/*++
Routine Description:
This routine sends a control packet to the host machine that is running the
kernel debugger and waits for an ACK.
Arguments:
PacketType - Supplies the type of packet to send.
PacketId - Supplies packet id, optionally.
Return Value:
None.
--*/
{
KD_PACKET PacketHeader;
//
// Initialize and send the packet header.
//
PacketHeader.PacketLeader = CONTROL_PACKET_LEADER;
if (ARGUMENT_PRESENT((PVOID)(ULONG_PTR)PacketId)) {
PacketHeader.PacketId = PacketId;
}
PacketHeader.PacketId = 0;
PacketHeader.ByteCount = 0;
PacketHeader.Checksum = 0;
PacketHeader.PacketType = PacketType;
// setup our send packet
RtlZeroMemory(&Kd1394Data->SendPacket, sizeof(DEBUG_1394_SEND_PACKET));
Kd1394Data->SendPacket.Length = 0;
RtlCopyMemory( &Kd1394Data->SendPacket.PacketHeader[0],
&PacketHeader,
sizeof(KD_PACKET)
);
Kd1394Data->SendPacket.TransferStatus = STATUS_PENDING;
return;
} // KdpSendControlPacket
ULONG
KdReceivePacket(
IN ULONG PacketType,
OUT PSTRING MessageHeader,
OUT PSTRING MessageData,
OUT PULONG DataLength,
IN OUT PKD_CONTEXT KdContext
)
/*++
Routine Description:
This routine receives a packet from the host machine that is running
the kernel debugger UI. This routine is ALWAYS called after packet being
sent by caller. It first waits for ACK packet for the packet sent and
then waits for the packet desired.
N.B. If caller is KdPrintString, the parameter PacketType is
PACKET_TYPE_KD_ACKNOWLEDGE. In this case, this routine will return
right after the ack packet is received.
Arguments:
PacketType - Supplies the type of packet that is excepted.
MessageHeader - Supplies a pointer to a string descriptor for the input
message.
MessageData - Supplies a pointer to a string descriptor for the input data.
DataLength - Supplies pointer to ULONG to receive length of recv. data.
KdContext - Supplies a pointer to the kernel debugger context.
Return Value:
KDP_PACKET_RESEND - if resend is required. = 2 = CP_GET_ERROR
KDP_PACKET_TIMEOUT - if timeout. = 1 = CP_GET_NODATA
KDP_PACKET_RECEIVED - if packet received. = 0 = CP_GET_SUCCESS
--*/
{
UCHAR Input;
ULONG MessageLength;
KD_PACKET PacketHeader;
ULONG ReturnCode;
ULONG Checksum;
ULONG Status;
// this dispatch gets called with PacketType != PACKET_TYPE_KD_POLL_BREAKIN for
// the number of times specified in KdCompNumberRetries (??). if we always timeout
// then we'll get called with PacketType == PACKET_TYPE_KD_POLL_BREAKIN
// make sure our link is enabled..
Dbg1394_EnablePhysicalAccess(Kd1394Data);
//
// Just check for breakin packet and return
//
if (PacketType == PACKET_TYPE_KD_POLL_BREAKIN) {
// let's peak into our receive packet and see if it's a breakin
if ((Kd1394Data->ReceivePacket.TransferStatus == STATUS_PENDING) &&
(Kd1394Data->ReceivePacket.Packet[0] == BREAKIN_PACKET_BYTE)) {
*KdDebuggerNotPresent = FALSE;
SharedUserData->KdDebuggerEnabled |= 0x00000002;
// we have a breakin packet
Kd1394Data->ReceivePacket.TransferStatus = STATUS_SUCCESS;
return(KDP_PACKET_RECEIVED);
}
else {
return(KDP_PACKET_TIMEOUT);
}
}
WaitForPacketLeader:
// read in our packet, if available...
ReturnCode = Dbg1394_ReadPacket( Kd1394Data,
&PacketHeader,
MessageHeader,
MessageData,
TRUE
);
//
// If we can successfully read packet leader, it has high possibility that
// kernel debugger is alive. So reset count.
//
if (ReturnCode != KDP_PACKET_TIMEOUT) {
KdCompNumberRetries = KdCompRetryCount;
}
if (ReturnCode != KDP_PACKET_RECEIVED) {
// see if it's a breakin packet...
if ((PacketHeader.PacketLeader & 0xFF) == BREAKIN_PACKET_BYTE) {
KdContext->KdpControlCPending = TRUE;
return(KDP_PACKET_RESEND);
}
return(ReturnCode);
}
//
// if the packet we received is a resend request, we return true and
// let caller resend the packet.
//
if (PacketHeader.PacketLeader == CONTROL_PACKET_LEADER &&
PacketHeader.PacketType == PACKET_TYPE_KD_RESEND) {
return(KDP_PACKET_RESEND);
}
//
// Check ByteCount received is valid
//
MessageLength = MessageHeader->MaximumLength;
if ((PacketHeader.ByteCount > (USHORT)PACKET_MAX_SIZE) ||
(PacketHeader.ByteCount < (USHORT)MessageLength)) {
goto SendResendPacket;
}
*DataLength = PacketHeader.ByteCount - MessageLength;
MessageData->Length = (USHORT)*DataLength;
MessageHeader->Length = (USHORT)MessageLength;
//
// Check PacketType is what we are waiting for.
//
if (PacketType != PacketHeader.PacketType) {
goto SendResendPacket;
}
//
// Check checksum is valid.
//
Checksum = KdpComputeChecksum(MessageHeader->Buffer, MessageHeader->Length);
Checksum += KdpComputeChecksum(MessageData->Buffer, MessageData->Length);
if (Checksum != PacketHeader.Checksum) {
goto SendResendPacket;
}
return(KDP_PACKET_RECEIVED);
SendResendPacket:
KdpSendControlPacket(PACKET_TYPE_KD_RESEND, 0L);
goto WaitForPacketLeader;
} // KdReceivePacket
void
KdSendPacket(
IN ULONG PacketType,
IN PSTRING MessageHeader,
IN PSTRING MessageData OPTIONAL,
IN OUT PKD_CONTEXT KdContext
)
/*++
Routine Description:
This routine sends a packet to the host machine that is running the
kernel debugger and waits for an ACK.
Arguments:
PacketType - Supplies the type of packet to send.
MessageHeader - Supplies a pointer to a string descriptor that describes
the message information.
MessageData - Supplies a pointer to a string descriptor that describes
the optional message data.
KdContext - Supplies a pointer to the kernel debugger context.
Return Value:
None.
--*/
{
KD_PACKET PacketHeader;
ULONG MessageDataLength;
ULONG ReturnCode;
PDBGKD_DEBUG_IO DebugIo;
PDBGKD_WAIT_STATE_CHANGE64 StateChange;
PDBGKD_FILE_IO FileIo;
BOOLEAN bException = FALSE;
PacketHeader.Checksum = 0;
if (ARGUMENT_PRESENT(MessageData)) {
MessageDataLength = MessageData->Length;
PacketHeader.Checksum = KdpComputeChecksum(MessageData->Buffer, MessageData->Length);
}
else {
MessageDataLength = 0;
PacketHeader.Checksum = 0;
}
PacketHeader.Checksum += KdpComputeChecksum(MessageHeader->Buffer, MessageHeader->Length);
//
// Initialize and send the packet header.
//
PacketHeader.PacketLeader = PACKET_LEADER;
PacketHeader.ByteCount = (USHORT)(MessageHeader->Length + MessageDataLength);
PacketHeader.PacketType = (USHORT)PacketType;
PacketHeader.PacketId = KdPacketId;
KdPacketId++;
KdCompNumberRetries = KdCompRetryCount;
// setup our send packet
RtlZeroMemory(&Kd1394Data->SendPacket, sizeof(DEBUG_1394_SEND_PACKET));
Kd1394Data->SendPacket.Length = 0;
// copy our packet header...
RtlCopyMemory( &Kd1394Data->SendPacket.PacketHeader[0],
&PacketHeader,
sizeof(KD_PACKET)
);
// setup our message header
if (MessageHeader) {
RtlCopyMemory( &Kd1394Data->SendPacket.Packet[0],
MessageHeader->Buffer,
MessageHeader->Length
);
Kd1394Data->SendPacket.Length += MessageHeader->Length;
}
// setup our message data
if (ARGUMENT_PRESENT(MessageData)) {
RtlCopyMemory( &Kd1394Data->SendPacket.Packet[Kd1394Data->SendPacket.Length],
MessageData->Buffer,
MessageData->Length
);
Kd1394Data->SendPacket.Length += MessageData->Length;
}
Kd1394Data->SendPacket.TransferStatus = STATUS_PENDING;
do {
// make sure our link is enabled..
Dbg1394_EnablePhysicalAccess(Kd1394Data);
if (KdCompNumberRetries == 0) {
//
// If the packet is not for reporting exception, we give up
// and declare debugger not present.
//
if (PacketType == PACKET_TYPE_KD_DEBUG_IO) {
DebugIo = (PDBGKD_DEBUG_IO)MessageHeader->Buffer;
if (DebugIo->ApiNumber == DbgKdPrintStringApi) {
*KdDebuggerNotPresent = TRUE;
SharedUserData->KdDebuggerEnabled &= ~0x00000002;
Kd1394Data->SendPacket.TransferStatus = STATUS_SUCCESS;
return;
}
}
else if (PacketType == PACKET_TYPE_KD_STATE_CHANGE64) {
StateChange = (PDBGKD_WAIT_STATE_CHANGE64)MessageHeader->Buffer;
if (StateChange->NewState == DbgKdLoadSymbolsStateChange) {
*KdDebuggerNotPresent = TRUE;
SharedUserData->KdDebuggerEnabled &= ~0x00000002;
Kd1394Data->SendPacket.TransferStatus = STATUS_SUCCESS;
return;
}
}
else if (PacketType == PACKET_TYPE_KD_FILE_IO) {
FileIo = (PDBGKD_FILE_IO)MessageHeader->Buffer;
if (FileIo->ApiNumber == DbgKdCreateFileApi) {
*KdDebuggerNotPresent = TRUE;
SharedUserData->KdDebuggerEnabled &= ~0x00000002;
Kd1394Data->SendPacket.TransferStatus = STATUS_SUCCESS;
return;
}
}
else {
bException = TRUE;
}
}
ReturnCode = KDP_PACKET_TIMEOUT;
{
ULONG count = 0;
volatile NTSTATUS *pStatus;
pStatus = &Kd1394Data->ReceivePacket.TransferStatus;
//
// now sit here and poll for a response from the target machine
//
do {
// make sure our link is enabled..
Dbg1394_EnablePhysicalAccess(Kd1394Data);
//
// while in this loop check if the host layed in a request.
// If they did, mark it read and double buffer it
//
count++;
if (Kd1394Data->SendPacket.TransferStatus != STATUS_PENDING) {
ReturnCode = KDP_PACKET_RECEIVED;
break;
}
if ((*pStatus == STATUS_PENDING) && (!bException)) {
ReturnCode = KDP_PACKET_RECEIVED;
break;
}
} while (count < TIMEOUT_COUNT);
}
if (ReturnCode == KDP_PACKET_TIMEOUT) {
KdCompNumberRetries--;
}
} while (ReturnCode != KDP_PACKET_RECEIVED);
//
// Since we are able to talk to debugger, the retrycount is set to
// maximum value.
//
KdCompRetryCount = KdContext->KdpDefaultRetries;
return;
} // KdSendPacket