entry.c

一个类似与Windows环境下的softice的源代码

/******************************************************************************
 *
 * Copyright (c) 2003 Gerhard W. Gruber
 *
 * PROJECT: pICE
 * $Source: /cvsroot/pice/pice/module/entry.c,v $
 * $Revision: 1.3 $
 * $Date: 2004/02/17 23:07:36 $
 * $Author: lightweave $
 * $Name:  $
 *
 * $Log: entry.c,v $
 * Revision 1.3  2004/02/17 23:07:36  lightweave
 *
 * Improved the DEBUG facillity and replaced the configuration handler with a
 * new code which now can read MS Windows INI style files. See CHANGES.txt for
 * more details.
 * Also added a macro which prevents compiling for kernels before 2.4.19.
 *
 * Revision 1.2  2003/06/18 22:00:22  lightweave
 * DEBUG and DEBUG_SERIAL added
 *
 *
 *****************************************************************************/

static char *ident = "$Header: /cvsroot/pice/pice/module/entry.c,v 1.3 2004/02/17 23:07:36 lightweave Exp $";


/*++

Copyright (c) 1998-2001 Klaus P. Gerlicher

Module Name:

    entry.c

Abstract:

    C entry point into debugger

Environment:

    Kernel mode only

Author:

    Klaus P. Gerlicher

Revision History:

    14-Oct-2001:	created

Copyright notice:

  This file may be distributed under the terms of the GNU Public License.

--*/

////////////////////////////////////////////////////
// INCLUDES
////
#include "remods.h"

#include <asm/io.h>
#include <linux/interrupt.h>

#include "precomp.h"

static char tempEntry[256];

BOOLEAN bStepThroughSource=FALSE;
BOOLEAN bStepInto = FALSE;
BOOLEAN bHasFixup = FALSE;

#ifdef __PICE__DEBUG__
static ULONG ulEnterCount = 0;
#endif // __DEBUG__

// registers save area (context)
ULONG CurrentDR0,CurrentDR1,CurrentDR2,CurrentDR3,CurrentDR6,CurrentDR7;
ULONG CurrentCR0,CurrentCR2,CurrentCR3,CurrentCR4;

BOOLEAN bNotifyToExit=FALSE; // TRUE when debugger should leave
BOOLEAN bDebuggerHaltState = FALSE;

char *szReasons[] =
{
"REASON_INT3",
"REASON_SINGLESTEP",
"REASON_HOTKEY",
"REASON_PAGEFAULT",
"REASON_GP_FAULT",
"REASON_HARDWARE_BP",
"REASON_DOUBLE_FAULT",
"REASON_MODULE_LOAD",
"REASON_INTERNAL_ERROR",
"REASON_SYSCALL",
"REASON_STACK_FAULT",
"REASON_INVALID_OPCODE_FAULT",
"REASON_DIVBYZERO_FAULT",
"REASON_TIMER",
"REASON_NMI",
"REASON_NOT_PRESENT",
"REASON_ALIGNMENT",
"REASON_BOOT_PARAMS",
"REASON_OTHER_CPU"
};

//*************************************************************************
// InternalError()
//
//*************************************************************************
void InternalError(EXCEPTION_FRAME* pFrame)
{
	// make sure nooe can take over
	__asm__ __volatile__("cli");

	// display debugger
	SaveGraphicsState();

	// show context
	DisplayRegs(pFrame);

	// notify user
    PICE_sprintf(tempEntry,"pICE: %.4X:%.8X (code %x)\n",pFrame->cs,pFrame->eip,pFrame->reason_code); 
	Print(OUTPUT_WINDOW,tempEntry); 
    Print(OUTPUT_WINDOW,"pICE: Please report this error to [e-mail]!\n");
    Print(OUTPUT_WINDOW,"pICE: !!! SYSTEM HALTED !!!\n");

	__asm__ __volatile__("hlt");
}

//*************************************************************************
// HandleEntry()
//
//*************************************************************************
ULONG HandleEntry(EXCEPTION_FRAME* pFrame)
{
   ULONG ulCallOldHandlerFlags;
   BOOLEAN bDontEnterShell; 

   ENTER_FUNC();

   DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "%8X (%p CPU #%u %s)++++++++++++++++++++++++++++++++++++++++++++++++++++++++ %s\n",
		  ++ulEnterCount,
		  current,
		  current->processor,
		  current->comm,
		  szReasons[pFrame->reason_code]);
   
   // set default reason_code on return
   // override this if necessary
   ulCallOldHandlerFlags = pFrame->reason_code;

   // don't assume we must call original handlers yet
   bDontEnterShell = TRUE;

   // control is not depressed
   bControl=FALSE; 

#if 0
    // dump registers 
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "EFL     = %.8X\n",pFrame->eflags);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "CS:EIP  = %.4X:%.8X\n",pFrame->cs,pFrame->eip);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "ERR     = %.8X\n",pFrame->error_code);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "REA     = %.8X\n",pFrame->reason_code);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "EAX     = %.8X\n",pFrame->eax);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "EBX     = %.8X\n",pFrame->ebx);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "ECX     = %.8X\n",pFrame->ecx);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "EDX     = %.8X\n",pFrame->edx);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "EBP     = %.8X\n",pFrame->ebp);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "ESP     = %.8X\n",pFrame->esp);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "ESI     = %.8X\n",pFrame->esi);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "EDI     = %.8X\n",pFrame->edi);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "DS      = %.4X\n",pFrame->ds);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "ES      = %.4X\n",pFrame->es);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "FS      = %.4X\n",pFrame->fs);
    DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "GS      = %.4X\n",pFrame->gs);

    // switched stacks on entry
    if(pFrame->cs != __KERNEL_CS)
    {
        DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "--- privilege switch ----\n");
        DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "SS:ESP  = %.4X:%.8X\n",pFrame->ring3_ss,pFrame->ring3_esp);
    }

    // check for V86 mode
    if(pFrame->eflags & VM_FLAG)
    {
        DPRINT(PICE_DEBUG, DBT_ENTRY, DBL_INFO, "--- V86 mode ----\n");
    }
#endif

	// why'd we come here?
    switch(pFrame->reason_code)
    {
        // page faults ***********************************************************************
        case REASON_PAGEFAULT:
            switch(HandlePageFault(pFrame))
            {
                case 0:
                    break;
                    // fall through
                case 1:
		            PICE_sprintf(tempEntry,"pICE: Breakpoint due to page fault at %.4X:%.8X\n",pFrame->cs,pFrame->eip); 
				    Print(OUTPUT_WINDOW,tempEntry); 
                    bDontEnterShell = FALSE;
                    break;
                case 2:
                    Print(OUTPUT_WINDOW,"pICE: !!! SYSTEM HALTED !!!\n");
					bDebuggerHaltState = TRUE;
                    bDontEnterShell = FALSE;
                    break;
            }
            break;
        // system calls **********************************************************************
        case REASON_SYSCALL:
            HandleSyscall(pFrame);
			break;
        // timer *****************************************************************************
        case REASON_TIMER:
            break;
        // single stepping *******************************************************************
		//
		// Why can we come here?
		// 
		// 1) Some application is under control of a user-mode debugger and is currently single-stepping
		// 2) PICE is single-stepping
		// 3) PICE needs to step over a SW breakpoint
		// 4) There's an error in PICE code
		//
		// How do we recognize the right situation?
		// 
		// 1) bStepping is not set and there's no breakpoint at the previous instruction
		// 2) bStepping is set
		// 3) bStepping is not set and there is a breakpoint at the previous instruction
        case REASON_SINGLESTEP:
			{
				ULONG ulAddressCurrent;

				// clear TF flag
				pFrame->eflags &= ~TF_FLAG; 

				// let noone else see the step
				ulCallOldHandlerFlags = REASON_HOTKEY;

				// this instruction
				ulAddressCurrent = GetLinearAddress(pFrame->cs,pFrame->eip);

				// if we came in because we needed to skip past a 
				// INT3 hook, we need to put the INT3 back in place and
				// simply restart the system.
				if(ulSingleStepCondition & SINGLE_STEP_CONDITION_BREAKPOINT_SKIP)
				{
					if(IsSwBpAtPreviousAddress(ulAddressCurrent))